Types of Plastic Bags: How Materials, Design, and Manufacturing Shape Your Options<\/title>\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n<link href=\"https:\/\/fonts.googleapis.com\/css2?family=Hammersmith+One&family=Open+Sans:wght@300..800&display=swap\" rel=\"stylesheet\">\n<\/head>\n<body style=\"margin:0;background:#FFFFFF;\">\n\n<div class=\"bd-post\">\n\n<style>\n\/* ==========================================================================\n BD-POST \u2014 TYPES OF PLASTIC BAGS (Variant 1)\n Design: blog-designer-present-v3\n Scope: every selector prefixed with .bd-post\n ========================================================================== *\/\n\n.bd-post {\n \/* ---- Palette ---- *\/\n --color-primary: #136AD5;\n --color-primary-hover: #0072FF;\n --color-primary-dark: #245AC5;\n --color-accent: #FF6A00;\n --color-accent-dark: #B84D00;\n --color-text: #333333;\n --text-primary: #333333;\n --accent-text: #0F4FA0;\n --color-text-secondary: #666666;\n --color-text-tertiary: #999999;\n --color-heading: #333333;\n --color-white: #FFFFFF;\n --color-near-black: #031008;\n --color-bg-white: #FFFFFF;\n --color-bg-light: #F6F6F6;\n --color-bg-off-white: #FAFAFA;\n --color-bg-cool: #F5F8FA;\n --color-footer-text: #99BBE6;\n --color-footer-muted: #9EACBD;\n --color-neutral-card: #F2F6FB;\n --color-neutral-border: #D7E7F2;\n --color-accent-text-grade: #0D4A99;\n\n \/* ---- Typography ---- *\/\n --font-body: \"Open Sans\", Sans-serif;\n --font-heading-display: \"Hammersmith One\", Sans-serif;\n --font-heading: \"Open Sans\", Sans-serif;\n\n \/* ---- Spacing ---- *\/\n --gap-attach: 16px;\n --gap-normal: 32px;\n --gap-section: 48px;\n --pad-compact: 16px;\n --pad-standard: 24px;\n\n \/* ---- Border radius ---- *\/\n --radius-sm: 3px;\n --radius-md: 6px;\n\n \/* ---- Shadows ---- *\/\n --shadow-subtle: 0px 0px 10px 0px rgba(0,0,0,0.05);\n --shadow-medium: 0px 0px 12px 0px rgba(0,0,0,0.15);\n\n \/* ---- Defaults ---- *\/\n font-family: var(--font-body);\n font-size: 16px;\n font-weight: 400;\n line-height: 1.6;\n color: var(--color-text);\n -webkit-font-smoothing: antialiased;\n -moz-osx-font-smoothing: grayscale;\n}\n\n\/* ---- Container ---- *\/\n.bd-post-article {\n width: 100%;\n max-width: none;\n margin: 0 auto;\n padding: 0;\n box-sizing: border-box;\n}\n\n\/* ---- Headings ---- *\/\n.bd-post h2 {\n font-family: var(--font-heading-display);\n font-size: 28px;\n font-weight: 400;\n line-height: 1.2;\n color: var(--text-primary);\n margin: 48px 0 16px 0;\n transition: color .2s ease-out, transform .2s ease-out;\n}\n\n.bd-post h2:hover {\n color: var(--accent-text);\n transform: translateX(2px);\n}\n\n.bd-post h3 {\n font-family: var(--font-heading);\n font-size: 20px;\n font-weight: 600;\n line-height: 1.2;\n color: var(--text-primary);\n margin: 32px 0 12px 0;\n}\n\n\/* The page template supplies the H1. Keep the first article H2 close to it. *\/\n.bd-post-article > h2:first-of-type {\n margin-top: 8px;\n}\n\n.bd-post h4 {\n font-family: var(--font-heading);\n font-size: 20px;\n font-weight: 700;\n line-height: 1.2;\n color: var(--color-heading);\n margin: 24px 0 8px 0;\n}\n\n\/* ---- Paragraph ---- *\/\n.bd-post p {\n margin: 0 0 1em 0;\n}\n\n.bd-post p:last-child {\n margin-bottom: 0;\n}\n\n\/* ---- Links ---- *\/\n.bd-post a {\n color: var(--color-primary);\n text-decoration: underline;\n text-underline-offset: 2px;\n overflow-wrap: anywhere;\n word-break: break-word;\n transition: color 0.3s;\n}\n\n.bd-post a:hover {\n color: var(--color-primary-hover);\n}\n\n\/* ---- Lists ---- *\/\n.bd-post ul,\n.bd-post ol {\n margin: 0 0 1em 0;\n padding-left: 1.5em;\n}\n\n.bd-post li {\n margin-bottom: 0.5em;\n}\n\n.bd-post ul {\n list-style-type: disc;\n}\n\n.bd-post ul ul {\n list-style-type: circle;\n}\n\n\/* ---- Inline code ---- *\/\n.bd-post code {\n background-color: #F6F6F6;\n font-family: \"SF Mono\", Monaco, Consolas, monospace;\n padding: 2px 6px;\n border-radius: var(--radius-sm);\n font-size: 14px;\n}\n\n\/* ---- Horizontal rule ---- *\/\n.bd-post hr {\n height: 1px;\n background-color: #C5D5E3;\n border: none;\n margin: 48px 0;\n}\n\n\/* ---- Table wrapper (for responsive scroll) ---- *\/\n.bd-post .table-wrapper {\n overflow-x: auto;\n margin-bottom: 1em;\n border-radius: var(--radius-md);\n border: 1px solid var(--color-neutral-border);\n}\n\n.bd-post table {\n width: 100%;\n border-collapse: collapse;\n font-size: 14px;\n}\n\n.bd-post th {\n background-color: var(--color-bg-cool);\n font-weight: 600;\n color: var(--color-text);\n padding: 10px 12px;\n text-align: left;\n border: 1px solid var(--color-neutral-border);\n}\n\n.bd-post td {\n padding: 10px 12px;\n border: 1px solid var(--color-neutral-border);\n color: var(--color-text);\n vertical-align: top;\n}\n\n\/* ---- Blockquote ---- *\/\n.bd-post blockquote {\n border-left: 4px solid var(--color-primary);\n padding: 16px 20px;\n margin: 0 0 1em 0;\n font-style: normal;\n color: var(--color-text);\n background-color: transparent;\n}\n\n\/* ---- Strong ---- *\/\n.bd-post strong {\n font-weight: 600;\n}\n\n\/* ==========================================================================\n BREAKPOINT STYLES\n ========================================================================== *\/\n\n\/* ----- BP-1 : Four-Dimension Framework (tip) ----- *\/\n.bd-post .bp-1-tip {\n display: flex;\n flex-direction: row;\n align-items: center;\n gap: 12px;\n padding: var(--pad-compact);\n margin-bottom: var(--gap-attach);\n background-color: var(--color-neutral-card);\n border: 1px solid var(--color-neutral-border);\n border-radius: var(--radius-md);\n}\n\n.bd-post .bp-1-tip .bp-accent-bar {\n width: 4px;\n align-self: stretch;\n background-color: var(--color-primary);\n border-radius: 2px;\n flex-shrink: 0;\n}\n\n.bd-post .bp-1-tip .bp-content {\n flex: 1;\n display: flex;\n flex-direction: column;\n gap: 6px;\n}\n\n.bd-post .bp-1-tip .bp-header {\n display: flex;\n align-items: center;\n gap: 6px;\n}\n\n.bd-post .bp-1-tip .bp-header svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-1-tip .bp-label {\n font-size: 14px;\n font-weight: 600;\n color: var(--color-text-secondary);\n letter-spacing: 0.5px;\n text-transform: uppercase;\n}\n\n.bd-post .bp-1-tip .bp-body {\n font-size: 14px;\n color: var(--color-text);\n}\n\n.bd-post .bp-1-tip .bp-dim-list {\n display: inline;\n font-size: 14px;\n color: var(--color-text);\n}\n\n.bd-post .bp-1-tip .bp-dim-list .dim-item {\n font-weight: 600;\n}\n\n.bd-post .bp-1-tip .bp-dim-list .dim-desc {\n font-weight: 400;\n}\n\n\/* ----- BP-2 : Polymer Comparison (table) ----- *\/\n.bd-post .bp-2-compare {\n display: flex;\n flex-direction: column;\n gap: 16px;\n padding: var(--pad-standard);\n margin-bottom: var(--gap-section);\n background-color: var(--color-neutral-card);\n border: 1px solid var(--color-neutral-border);\n border-radius: var(--radius-md);\n}\n\n.bd-post .bp-2-compare .bp-header {\n display: flex;\n align-items: center;\n gap: 8px;\n}\n\n.bd-post .bp-2-compare .bp-header svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-2-compare .bp-label {\n font-size: 14px;\n font-weight: 600;\n color: var(--color-text-secondary);\n letter-spacing: 0.5px;\n text-transform: uppercase;\n}\n\n.bd-post .bp-2-compare .bp-table {\n width: 100%;\n border-collapse: collapse;\n font-size: 14px;\n}\n\n.bd-post .bp-2-compare .bp-table th {\n background-color: var(--color-bg-cool);\n font-weight: 600;\n color: var(--color-text);\n padding: 8px 10px;\n text-align: left;\n border-bottom: 1px solid var(--color-neutral-border);\n}\n\n.bd-post .bp-2-compare .bp-table td {\n padding: 8px 10px;\n border-bottom: 1px solid var(--color-neutral-border);\n color: var(--color-text);\n vertical-align: top;\n}\n\n.bd-post .bp-2-compare .bp-table tr:last-child td {\n border-bottom: none;\n}\n\n.bd-post .bp-2-compare .bp-table .prop-col {\n font-weight: 600;\n color: var(--color-accent-text-grade);\n white-space: nowrap;\n}\n\n\/* ----- BP-3 : Key Insight (stand-up pouch capital reality) ----- *\/\n.bd-post .bp-3-insight {\n display: flex;\n flex-direction: column;\n gap: 12px;\n padding: var(--pad-standard);\n margin-bottom: var(--gap-section);\n background-color: var(--color-neutral-card);\n border: 1px solid var(--color-neutral-border);\n border-radius: var(--radius-md);\n}\n\n.bd-post .bp-3-insight .bp-header {\n display: flex;\n align-items: center;\n gap: 8px;\n}\n\n.bd-post .bp-3-insight .bp-header svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-3-insight .bp-label {\n font-size: 14px;\n font-weight: 600;\n color: var(--color-accent-dark);\n letter-spacing: 0.5px;\n text-transform: uppercase;\n}\n\n.bd-post .bp-3-insight .bp-body {\n font-size: 15px;\n color: var(--color-text);\n}\n\n.bd-post .bp-3-insight .bp-stats {\n display: flex;\n flex-direction: row;\n gap: 12px;\n}\n\n.bd-post .bp-3-insight .bp-stat-card {\n flex: 1;\n background-color: var(--color-white);\n border: 1px solid var(--color-neutral-border);\n border-radius: 4px;\n padding: 10px 14px;\n text-align: center;\n}\n\n.bd-post .bp-3-insight .bp-stat-card .stat-number {\n font-size: 20px;\n font-weight: 700;\n color: var(--color-accent-text-grade);\n line-height: 1.2;\n}\n\n.bd-post .bp-3-insight .bp-stat-card .stat-label {\n font-size: 13px;\n color: var(--color-text-secondary);\n line-height: 1.4;\n}\n\n\/* ----- BP-4 : Blown Film Process (flow) ----- *\/\n.bd-post .bp-4-process {\n display: flex;\n flex-direction: column;\n gap: 20px;\n padding: var(--pad-standard);\n margin-bottom: var(--gap-normal);\n background-color: var(--color-neutral-card);\n border: 1px solid var(--color-neutral-border);\n border-radius: var(--radius-md);\n}\n\n.bd-post .bp-4-process .bp-header {\n display: flex;\n align-items: center;\n gap: 8px;\n}\n\n.bd-post .bp-4-process .bp-header svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-4-process .bp-label {\n font-size: 14px;\n font-weight: 600;\n color: var(--color-text-secondary);\n letter-spacing: 0.5px;\n text-transform: uppercase;\n}\n\n.bd-post .bp-4-process .bp-flow {\n display: flex;\n flex-direction: row;\n align-items: center;\n gap: 0;\n}\n\n.bd-post .bp-4-process .bp-flow-step {\n flex: 1;\n display: flex;\n flex-direction: column;\n align-items: center;\n gap: 8px;\n text-align: center;\n}\n\n.bd-post .bp-4-process .bp-flow-step .step-circle {\n width: 28px;\n height: 28px;\n background-color: var(--color-primary);\n color: var(--color-white);\n border-radius: 50%;\n display: flex;\n align-items: center;\n justify-content: center;\n font-size: 14px;\n font-weight: 700;\n flex-shrink: 0;\n line-height: 1;\n}\n\n.bd-post .bp-4-process .bp-flow-step .step-label {\n font-size: 13px;\n font-weight: 600;\n color: var(--color-text);\n line-height: 1.3;\n}\n\n.bd-post .bp-4-process .bp-flow-step .step-sub {\n font-size: 12px;\n color: var(--color-text-secondary);\n line-height: 1.3;\n white-space: nowrap;\n}\n\n.bd-post .bp-4-process .bp-flow-arrow {\n flex: 0 0 auto;\n display: flex;\n align-items: center;\n justify-content: center;\n width: 32px;\n height: 28px;\n color: var(--color-text-tertiary);\n}\n\n.bd-post .bp-4-process .bp-flow-arrow svg {\n display: block;\n width: 20px;\n height: 20px;\n}\n\n.bd-post .bp-4-process .bp-caption {\n font-size: 13px;\n color: var(--color-text-secondary);\n font-style: italic;\n text-align: center;\n}\n\n\/* ----- BP-5 : Mid CTA (Accent solid-fill) ----- *\/\n.bd-post .bp-5-cta {\n display: flex;\n flex-direction: column;\n align-items: center;\n text-align: center;\n gap: 16px;\n padding: var(--pad-standard);\n margin-bottom: var(--gap-section);\n background-color: #0A3570;\n border-radius: var(--radius-md);\n color: var(--color-white);\n}\n\n.bd-post .bp-5-cta svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-5-cta .cta-icon {\n opacity: 0.9;\n}\n\n.bd-post .bp-5-cta .cta-title {\n font-size: 22px;\n font-weight: 700;\n color: var(--color-white);\n line-height: 1.3;\n margin: 0;\n}\n\n.bd-post .bp-5-cta .cta-subtitle {\n font-size: 18px;\n font-weight: 700;\n color: #FFFFFF;\n max-width: 480px;\n line-height: 1.5;\n margin: 0;\n}\n\n.bd-post .bp-5-cta .cta-btn {\n display: inline-block;\n background-color: var(--color-white);\n color: var(--color-primary);\n font-size: 16px;\n font-weight: 600;\n padding: 14px 28px;\n border: 2px solid #99BBE6;\n border-radius: var(--radius-md);\n text-decoration: none;\n transition: background-color 0.3s, color 0.3s;\n}\n\n.bd-post .bp-5-cta .cta-btn:hover {\n background-color: #FFFFFF;\n color: var(--color-accent-text-grade);\n}\n\n\/* ----- BP-6 : Incoming Inspection Checklist ----- *\/\n.bd-post .bp-6-checklist {\n display: flex;\n flex-direction: row;\n align-items: flex-start;\n gap: 12px;\n padding: var(--pad-compact);\n margin-bottom: var(--gap-attach);\n background-color: var(--color-neutral-card);\n border: 1px solid var(--color-neutral-border);\n border-radius: var(--radius-md);\n}\n\n.bd-post .bp-6-checklist .bp-accent-bar {\n width: 4px;\n align-self: stretch;\n background-color: var(--color-primary);\n border-radius: 2px;\n flex-shrink: 0;\n}\n\n.bd-post .bp-6-checklist .bp-content {\n flex: 1;\n display: flex;\n flex-direction: column;\n gap: 10px;\n}\n\n.bd-post .bp-6-checklist .bp-header {\n display: flex;\n align-items: center;\n gap: 6px;\n}\n\n.bd-post .bp-6-checklist .bp-header svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-6-checklist .bp-label {\n font-size: 14px;\n font-weight: 600;\n color: var(--color-text-secondary);\n letter-spacing: 0.5px;\n text-transform: uppercase;\n}\n\n.bd-post .bp-6-checklist .bp-item {\n display: flex;\n align-items: flex-start;\n gap: 8px;\n font-size: 14px;\n color: var(--color-text);\n}\n\n.bd-post .bp-6-checklist .bp-item svg {\n flex-shrink: 0;\n display: block;\n margin-top: 2px;\n}\n\n\/* ----- BP-7 : End CTA (Inverse solid-fill) ----- *\/\n.bd-post .bp-7-cta {\n display: flex;\n flex-direction: column;\n align-items: center;\n text-align: center;\n gap: 18px;\n padding: var(--pad-standard);\n margin-bottom: 0;\n background-color: var(--color-near-black);\n border-radius: var(--radius-md);\n color: var(--color-white);\n}\n\n.bd-post .bp-7-cta svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-7-cta .cta-title {\n font-size: 24px;\n font-weight: 700;\n color: var(--color-white);\n line-height: 1.3;\n margin: 0;\n}\n\n.bd-post .bp-7-cta .cta-subtitle {\n font-size: 16px;\n color: var(--color-footer-muted);\n max-width: 500px;\n line-height: 1.5;\n margin: 0;\n}\n\n.bd-post .bp-7-cta .cta-chips {\n display: flex;\n flex-direction: row;\n flex-wrap: wrap;\n gap: 8px;\n justify-content: center;\n}\n\n.bd-post .bp-7-cta .cta-chip {\n font-size: 12px;\n color: var(--color-footer-text);\n border: 1px solid var(--color-footer-text);\n border-radius: 100px;\n padding: 4px 12px;\n line-height: 1.4;\n}\n\n.bd-post .bp-7-cta .cta-btn {\n display: inline-block;\n background-color: var(--color-primary);\n color: var(--color-white);\n font-size: 16px;\n font-weight: 600;\n padding: 14px 28px;\n border-radius: var(--radius-md);\n text-decoration: none;\n transition: background-color 0.3s, color 0.3s;\n}\n\n.bd-post .bp-7-cta a.cta-btn,\n.bd-post .bp-7-cta a.cta-btn:visited {\n color: #FFFFFF !important;\n}\n\n.bd-post .bp-7-cta .cta-btn:hover {\n background-color: var(--color-white);\n color: var(--color-near-black);\n}\n\n\/* ==========================================================================\n MOTION\n ========================================================================== *\/\n\n@media (prefers-reduced-motion: no-preference) {\n \/* Scroll reveal \u2014 fade up *\/\n @supports (animation-timeline: view()) {\n .bd-post .bp-1-tip,\n .bd-post .bp-2-compare,\n .bd-post .bp-3-insight,\n .bd-post .bp-4-process,\n .bd-post .bp-5-cta,\n .bd-post .bp-6-checklist,\n .bd-post .bp-7-cta {\n animation: bd-fade-up 0.6s ease-out both;\n animation-timeline: view();\n animation-range: entry 0% entry 20%;\n }\n }\n\n \/* Card hover lift on neutral BPs *\/\n .bd-post .bp-1-tip:hover,\n .bd-post .bp-2-compare:hover,\n .bd-post .bp-3-insight:hover,\n .bd-post .bp-4-process:hover,\n .bd-post .bp-6-checklist:hover {\n transform: translateY(-2px);\n box-shadow: var(--shadow-medium);\n transition: transform 0.3s, box-shadow 0.3s;\n }\n\n \/* Link underline \u2014 handled via text-decoration-color transition above *\/\n}\n\n@keyframes bd-fade-up {\n from {\n opacity: 0;\n transform: translateY(12px);\n }\n to {\n opacity: 1;\n transform: translateY(0);\n }\n}\n\n\/* ==========================================================================\n MOBILE (max-width: 768px)\n ========================================================================== *\/\n\n@media (max-width: 768px) {\n .bd-post-article {\n padding: 0 16px;\n }\n\n .bd-post h1 {\n font-size: 34px;\n }\n\n .bd-post h2 {\n font-size: 28px;\n margin-top: 32px;\n margin-bottom: 16px;\n }\n\n .bd-post h3 {\n font-size: 20px;\n margin-top: 24px;\n margin-bottom: 12px;\n }\n\n .bd-post h4 {\n font-size: 18px;\n }\n\n \/* BP margin adjustments *\/\n .bd-post .bp-1-tip,\n .bd-post .bp-6-checklist {\n padding: 12px;\n }\n\n .bd-post .bp-2-compare,\n .bd-post .bp-3-insight,\n .bd-post .bp-4-process,\n .bd-post .bp-5-cta,\n .bd-post .bp-7-cta {\n padding: 18px;\n }\n\n \/* BP-4 flow \u2192 vertical stack *\/\n .bd-post .bp-4-process .bp-flow {\n flex-direction: column;\n gap: 12px;\n }\n\n .bd-post .bp-4-process .bp-flow-step {\n flex: none;\n width: 100%;\n flex-direction: row;\n gap: 12px;\n text-align: left;\n }\n\n .bd-post .bp-4-process .bp-flow-step .step-label-wrap {\n text-align: left;\n }\n\n .bd-post .bp-4-process .bp-flow-arrow {\n transform: rotate(90deg);\n height: auto;\n width: 28px;\n align-self: center;\n }\n\n .bd-post .bp-4-process .bp-flow-step .step-circle {\n flex-shrink: 0;\n }\n\n \/* BP-3 stats stack *\/\n .bd-post .bp-3-insight .bp-stats {\n flex-direction: column;\n }\n\n \/* BP-5 CTA *\/\n .bd-post .bp-5-cta .cta-title {\n font-size: 20px;\n }\n\n \/* BP-7 CTA *\/\n .bd-post .bp-7-cta .cta-title {\n font-size: 22px;\n }\n\n \/* Table font-size *\/\n .bd-post table {\n font-size: 13px;\n }\n\n .bd-post th,\n .bd-post td {\n padding: 8px 10px;\n }\n}\n\n\/* ==========================================================================\n PRINT\n ========================================================================== *\/\n\n@media print {\n .bd-post .bp-5-cta,\n .bd-post .bp-7-cta {\n break-inside: avoid;\n page-break-inside: avoid;\n }\n}\n<\/style>\n\n<article class=\"bd-post-article\">\n\n \n \n \n \n \n \n <p>Walk into any supermarket, and you will handle at least three different types of plastic bags before you reach the checkout \u2014 the transparent produce bag, the crinkly shopping bag at the register, and maybe a resealable freezer bag waiting at home. They all look like “plastic bags,” but they are fundamentally different products: different materials, different structures, and made on entirely different production lines.<\/p>\n\n <p>Understanding those differences matters whether you are a procurement manager choosing packaging for a food brand, a factory owner deciding which bag types to produce, or simply someone who wants to know what you are actually buying. This guide covers every major dimension: the polymers that determine a bag’s feel and performance, the structural designs that dictate how it works, the manufacturing processes behind each type, and the practical question of which bag fits which job.<\/p>\n\n \n \n \n <div class=\"bp-1-tip\">\n <div class=\"bp-accent-bar\"><\/div>\n <div class=\"bp-content\">\n <div class=\"bp-header\">\n <svg viewbox=\"0 0 24 24\" width=\"20\" height=\"20\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);\">\n <circle cx=\"12\" cy=\"12\" r=\"10\"\/>\n <line x1=\"12\" y1=\"16\" x2=\"12\" y2=\"12\"\/>\n <line x1=\"12\" y1=\"8\" x2=\"12.01\" y2=\"8\"\/>\n <\/svg>\n <span class=\"bp-label\">Evaluation Framework<\/span>\n <\/div>\n <div class=\"bp-body\">\n Every material is assessed across four dimensions:\n <span class=\"bp-dim-list\">\n <span class=\"dim-item\">Mechanical<\/span> <span class=\"dim-desc\">(strength\/flexibility)<\/span> ·\n <span class=\"dim-item\">Thermal<\/span> <span class=\"dim-desc\">(melting\/sealing)<\/span> ·\n <span class=\"dim-item\">Optical<\/span> <span class=\"dim-desc\">(clarity\/haze)<\/span> ·\n <span class=\"dim-item\">\u00c9conomique<\/span> <span class=\"dim-desc\">(cost\/processing)<\/span>\n <\/span>\n <\/div>\n <\/div>\n <\/div>\n\n \n \n \n <h2>Material-Based Types \u2014 Understanding Plastic Bag Polymers<\/h2>\n\n <p>The polymer is not just a “material choice” \u2014 it dictates the bag’s feel, strength, temperature tolerance, cost structure, and even which markets you can legally sell into. Before diving into specific materials, here is a four-dimension framework to evaluate any plastic bag polymer: <strong>mechanical performance<\/strong> (strength and flexibility), <strong>thermal behavior<\/strong> (melting point and heat-seal temperature), <strong>optical properties<\/strong> (transparency and haze), and <strong>economics<\/strong> (raw material cost and processing difficulty). Every material covered below is assessed along these four lines.<\/p>\n\n\n<img decoding=\"async\" src=\"https:\/\/www.ketegroup.com\/wp-content\/uploads\/2026\/05\/types-of-plastic-bags-for-food-packaging-1.webp\" \n alt=\"types de sacs en plastique pour l'emballage alimentaire 1\" \n style=\"width: 512px; height: 384px; max-width: 100%; object-fit: cover; border-radius: 12px; margin: 30px auto; display: block; box-shadow: 10px 10px 60px 0px rgba(210, 221, 224, 0.35); transition: all 0.3s ease; cursor: pointer;\"\n onmouseover=\"this.style.transform='translateY(-5px) scale(1.03)'; this.style.boxShadow='15px 25px 80px 0px rgba(210, 221, 224, 0.45)';\"\n onmouseout=\"this.style.transform='translateY(0) scale(1)'; this.style.boxShadow='10px 10px 60px 0px rgba(210, 221, 224, 0.35)';\">\n\n \n <h3>HDPE (High-Density Polyethylene) \u2014 The Workhorse of Plastic Bags<\/h3>\n\n <p>HDPE is the most common plastic bag material on the planet \u2014 and the one you have almost certainly used today. It is the crisp, slightly crinkly, semi-transparent material behind supermarket singlet bags and bin liners.<\/p>\n\n <p>The numbers explain why. HDPE has a density of 0.94\u20130.97 g\/cm\u00b3 and a tensile yield strength of 20\u201330 MPa (<a href=\"https:\/\/www.astm.org\/d4976-12ar20.html\" rel=\"nofollow\">ASTM D4976<\/a>, 2020). It melts at 120\u2013130\u00b0C and crystallizes to 80\u201390%, which gives it that characteristic stiffness and the frosted, milky appearance. At 15\u201325 microns, you get a standard supermarket T-shirt bag that holds 3\u20135 kg; at 30\u201350 microns, it becomes a bin liner with enough tear resistance for household waste.<\/p>\n\n <p>The reason HDPE dominates is straightforward: at equal thickness, it is roughly 3\u20134 times stronger than LDPE. That means you use less material to achieve the same strength, making it the most cost-effective option for high-volume applications. The trade-off is flexibility \u2014 HDPE bags feel stiff, they crinkle audibly, and they lack the transparent, premium look that retail brands often want.<\/p>\n\n <p><strong>Meilleur pour :<\/strong> grocery bags, bin liners, industrial packaging where cost-per-unit and strength matter more than appearance.<\/p>\n\n \n <h3>LDPE (Low-Density Polyethylene) \u2014 Flexibility and Clarity<\/h3>\n\n <p>If HDPE is the workhorse, LDPE is the showroom model. It is soft, glossy, and highly transparent \u2014 the material behind boutique shopping bags, bread bags, and garment covers from the dry cleaner.<\/p>\n\n <p>The structural difference is in the polymer chains. LDPE’s highly branched molecular structure limits crystallization to 45\u201355%, producing density in the 0.91\u20130.94 g\/cm\u00b3 range. Tensile strength drops to 8\u201315 MPa \u2014 far below HDPE \u2014 but what you lose in strength you gain in flexibility, clarity, and heat-sealability. LDPE has a Vicat softening point of 85\u201395\u00b0C, which means it seals easily at lower temperatures and faster line speeds. It stays flexible down to -60\u00b0C, which is why frozen food packaging almost always involves LDPE or its blends.<\/p>\n\n <p>The practical trade-offs: LDPE costs more per unit of strength than HDPE, and it is sensitive to oils and greases, which can cause environmental stress cracking over time. That bakery bag holds bread beautifully but would fail quickly with oily fried food \u2014 which is why some food applications need a multi-layer structure with a barrier layer.<\/p>\n\n <p><strong>Meilleur pour :<\/strong> retail shopping bags, bread and produce bags, shrink wrap, garment covers, and any application where transparency and tactile quality matter.<\/p>\n\n \n <h3>LLDPE (Linear Low-Density Polyethylene) \u2014 The Strength Upgrade<\/h3>\n\n <p>LLDPE is the material that many buyers do not know they need. It looks and feels similar to LDPE, but at identical thickness, it delivers 2\u20133 times the puncture and tear resistance. The reason is in the molecular architecture: where LDPE has long, chaotic branches, LLDPE has short, uniform branches that produce a more even crystalline structure \u2014 not more crystals, just better-organized ones.<\/p>\n\n <p>Density falls in the same 0.915\u20130.940 g\/cm\u00b3 range as LDPE, but Dart Drop Impact values typically exceed 200 g\/\u00b5m versus 100\u2013150 g\/\u00b5m for LDPE (<a href=\"https:\/\/www.astm.org\/d1709-22.html\" rel=\"nofollow\">ASTM D1709<\/a>). Elmendorf tear strength is significantly higher in both machine and transverse directions. On the processing side, LLDPE requires higher extrusion temperatures (190\u2013260\u00b0C versus 176\u2013232\u00b0C for LDPE) and greater motor torque \u2014 an important consideration if you run your own production line.<\/p>\n\n <p>In practice, most “heavy-duty” garbage bags and industrial liners are LDPE-LLDPE blends rather than pure LDPE. Pure LDPE simply cannot deliver the puncture resistance needed for construction waste or sharp-edged industrial scrap. Freezer bags are another LLDPE stronghold, where cold-temperature impact resistance prevents the bag from shattering when dropped.<\/p>\n\n <p>A variant worth knowing: mLLDPE (metallocene-catalyzed LLDPE) offers a narrower molecular weight distribution, which translates to better heat-seal performance and improved optical clarity \u2014 at a higher raw material cost.<\/p>\n\n <p><strong>Meilleur pour :<\/strong> freezer bags, heavy-duty garbage bags, industrial liners, and any application where puncture resistance or cold-temperature performance is non-negotiable.<\/p>\n\n \n <h3>PP (Polypropylene) \u2014 The Premium Performer<\/h3>\n\n <p>Polypropylene is not what most people picture when they think “plastic bag” \u2014 but it should be. PP bags are crystal-clear, stiff, and heat-resistant to 160\u00b0C, making them the material of choice for high-visibility retail packaging, snack foods, and medical sterilization pouches.<\/p>\n\n <p>PP’s density is the lowest of the group at 0.90\u20130.91 g\/cm\u00b3, and its tensile strength of 30\u201340 MPa rivals HDPE. The defining advantage is thermal: a melting point of 160\u2013165\u00b0C for homopolymer PP means it can survive hot-fill processes and steam sterilization that would destroy any PE bag. BOPP (biaxially oriented polypropylene) takes this further \u2014 stretching the film in two directions creates a material with haze as low as 1\u20132%, rivaling glass in clarity, which is why premium snack and confectionery packaging almost always uses BOPP.<\/p>\n\n <p>The critical limitation: pure homopolymer PP becomes brittle around 0\u00b0C. Drop a frozen food bag made of pure PP, and it may shatter. Copolymer grades address this, pushing the brittle point down to roughly -20\u00b0C, but at added cost. UV stability is another weakness \u2014 PP degrades faster than PE under sunlight unless stabilizers are added.<\/p>\n\n <p><strong>Meilleur pour :<\/strong> premium retail bags, snack and confectionery packaging (BOPP), medical sterilization pouches, woven sacks for bulk grains and fertilizers.<\/p>\n\n \n \n \n <div class=\"bp-2-compare\">\n <div class=\"bp-header\">\n <svg viewbox=\"0 0 24 24\" width=\"24\" height=\"24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);\">\n <path d=\"M12 20V10\"\/>\n <path d=\"M18 20V4\"\/>\n <path d=\"M6 20v-4\"\/>\n <\/svg>\n <span class=\"bp-label\">Polymer Comparison<\/span>\n <\/div>\n <table class=\"bp-table\">\n <thead>\n <tr>\n <th>Propri\u00e9t\u00e9<\/th>\n <th>PEHD<\/th>\n <th>LDPE<\/th>\n <th>LLDPE<\/th>\n <th>PP<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr>\n <td class=\"prop-col\">Densit\u00e9<\/td>\n <td>0.94\u20130.97 g\/cm\u00b3<\/td>\n <td>0.91\u20130.94 g\/cm\u00b3<\/td>\n <td>0.915\u20130.940 g\/cm\u00b3<\/td>\n <td>0.90\u20130.91 g\/cm\u00b3<\/td>\n <\/tr>\n <tr>\n <td class=\"prop-col\">R\u00e9sistance \u00e0 la traction<\/td>\n <td>20\u201330 MPa<\/td>\n <td>8\u201315 MPa<\/td>\n <td>Dart Drop >200 g\/\u00b5m<\/td>\n <td>30\u201340 MPa<\/td>\n <\/tr>\n <tr>\n <td class=\"prop-col\">Melting Point<\/td>\n <td>120\u2013130\u00b0C<\/td>\n <td>85\u201395\u00b0C (Vicat)<\/td>\n <td>190\u2013260\u00b0C (extrusion)<\/td>\n <td>160\u2013165\u00b0C<\/td>\n <\/tr>\n <tr>\n <td class=\"prop-col\">Meilleur pour<\/td>\n <td>Grocery bags, bin liners<\/td>\n <td>Retail, bread bags, garment covers<\/td>\n <td>Freezer bags, heavy-duty liners<\/td>\n <td>Premium retail, BOPP, medical<\/td>\n <\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n \n \n \n <h2>Design and Structure Types \u2014 How Plastic Bags Are Built<\/h2>\n\n <p>Material determines the bag’s feel, but design determines what it can actually do. A bag’s structure governs how it loads, how it carries, how it seals, and how it presents on a shelf. Four dimensions define any bag design: <strong>loading method<\/strong> (open top, side access, expandable volume), <strong>carrying method<\/strong> (handle type or none), <strong>closure method<\/strong> (single-use seal, resealable, or none), and <strong>display method<\/strong> (flat lay, hanging, or standing).<\/p>\n\n \n <h3>Flat Bags, Gusseted Bags, and Poly Tubing \u2014 The Fundamental Forms<\/h3>\n\n <p>Flat poly bags are exactly what they sound like: two sheets of film sealed on three sides, open on the fourth. They are the simplest, cheapest, and fastest to produce \u2014 bottom-seal versions run at 250\u2013500 bags per minute on standard equipment. Side-seal variants suit automated packing lines where the bag is opened, filled, and sealed by machine.<\/p>\n\n <p>Gusseted bags add expandable folds to the sides or bottom, letting the bag hold bulkier, irregularly shaped items without stretching or tearing. A bottom gusset turns a flat bag into something that can stand upright \u2014 the foundational structure behind coffee bean bags, pet food packaging, and e-commerce mailers. Gusset depths typically range from 5 to 20 cm (2\u20138 inches), and the expandable volume gain over a flat bag of the same width can hit 30\u201350%.<\/p>\n\n <p>Poly tubing sits at the simplest end of the spectrum: a continuous roll of film available in widths from 2.5 cm to over 3 meters, which the user cuts and seals to custom lengths. For low-volume or variable-length packaging, it is the cheapest option per unit.<\/p>\n\n \n <h3>T-Shirt Bags, Handle Bags, and Carry-Out Designs \u2014 Built for Convenience<\/h3>\n\n <p>The T-shirt bag \u2014 the classic supermarket singlet \u2014 is the highest-volume plastic bag design in the world. It is an HDPE bag with integrated loop handles die-cut from the bag body, typically 30\u201346 cm wide by 46\u201361 cm long, at 15\u201325 microns. Production speed reaches 120\u2013250 bags per minute on twin-line machines. Cost per unit can drop below one cent at volume.<\/p>\n\n <p>Soft loop handle bags use LDPE for a more flexible, premium feel and are the standard for boutique and department store retail. Die-cut handle bags take the handle-from-body concept further with precisely cut openings that create a sleeker, more branded look \u2014 common in mid-to-high-end retail where the bag is part of the customer experience.<\/p>\n\n <p>Patch handle bags add a separate reinforced handle piece, pushing load capacity to 5\u201310 kg. They suit heavier items \u2014 books, hardware, bulk groceries \u2014 where an integrated T-shirt handle would tear. The cost premium over a T-shirt bag is roughly 2\u20133 times, driven by the extra material and the additional handle-sealing station on the production line.<\/p>\n\n <p>A procurement reality worth noting: T-shirt bag machines and soft-loop handle bag machines are fundamentally different equipment. If you invest in one, you cannot simply switch tooling to produce the other \u2014 a fact that shapes the production strategy of every bag factory.<\/p>\n\n \n <h3>Zipper Bags, Slider Bags, and Resealable Closures \u2014 Repeated Access Design<\/h3>\n\n <p>Resealable bags solve a specific problem: the product inside is consumed over time, not all at once. Press-to-close zippers are the most common and cost-effective design, used for frozen vegetables, shredded cheese, and deli meats. Slider zippers add a plastic slider that glides along the track, making opening and closing easier \u2014 important for products targeting elderly consumers or for bags opened dozens of times, like bulk snacks or pet food.<\/p>\n\n <p>The engineering challenge is the zipper opening force. Too tight, and consumers complain or return the product. Too loose, and the bag leaks \u2014 or worse, loses its oxygen barrier and causes spoilage. The industry sweet spot is 5\u201315 N of opening force. Dual-track zippers can achieve 3 times the air-tightness of single-track designs, which matters for coffee beans, nuts, and other oxygen-sensitive products.<\/p>\n\n <p>On the production side, zipper insertion adds a dedicated station to the bag-making machine, slowing line speed from 250\u2013500 bags per minute (for flat bags) to 100\u2013150 for zipper bags. The zipper material itself \u2014 typically LDPE or PP \u2014 must match the bag body polymer to avoid recycling compatibility issues.<\/p>\n\n <p>For procurement managers, one practical verification step: always request zipper opening force test data from your supplier. This single parameter accounts for a disproportionate share of consumer complaints about resealable packaging.<\/p>\n\n \n <h3>Stand-Up Pouches, Bottom-Gusset Bags, and Specialty Structures \u2014 Shelf-Ready Packaging<\/h3>\n\n <p>The stand-up pouch has transformed retail packaging in the last decade. Walk down any snack aisle, and you will see why: a pouch that stands upright on the shelf, with a large printable front panel, a bottom gusset for stability, and multi-layer construction for barrier performance. It is the most technically sophisticated bag type \u2014 and the most expensive to produce.<\/p>\n\n <p>A typical stand-up pouch for food uses a three-layer laminate: 12-micron PET for outer print surface and stiffness, 7\u20139-micron aluminum foil for the oxygen and moisture barrier, and 50\u201380-micron PE for the inner heat-seal layer. Oxygen transmission rates below 1 cc\/m\u00b2\/day are achievable with the aluminum foil layer \u2014 essential for products like coffee, nuts, and jerky where oxidation means staleness.<\/p>\n\n <p>Flat-bottom box pouches take the concept further with a rectangular base that provides better shelf stability and a more premium look. Spout pouches add a fitted pour spout for liquid products \u2014 think laundry detergent, sports drinks, and baby food purees.<\/p>\n\n <p>The capital reality: a stand-up pouch machine belongs to an entirely different class of equipment from a flat bag machine. Production speeds drop to 40\u201380 pouches per minute, scrap rates run 5\u20138% versus 1\u20132% for simple bags, and the machine itself costs several multiples more. This is why most food startups buy pouches from converters rather than producing them in-house \u2014 the barrier to entry is genuinely high.<\/p>\n\n \n \n \n <div class=\"bp-3-insight\">\n <div class=\"bp-header\">\n <svg viewbox=\"0 0 24 24\" width=\"24\" height=\"24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-accent);\">\n <path d=\"M9 18h6\"\/>\n <path d=\"M10 22h4\"\/>\n <path d=\"M15.09 14c.18-.98.65-1.74 1.41-2.5A4.65 4.65 0 0 0 18 8 6 6 0 0 0 6 8c0 1 .23 2.23 1.5 3.5A4.61 4.61 0 0 1 8.91 14\"\/>\n <\/svg>\n <span class=\"bp-label\">Point cl\u00e9<\/span>\n <\/div>\n <div class=\"bp-body\">\n The stand-up pouch machine belongs to an entirely different class from a flat bag machine \u2014 production speeds of 40\u201380 pouches per minute versus 250\u2013500, scrap rates of 5\u20138% versus 1\u20132%, and a machine cost several times higher. This is why most food startups buy pouches from converters rather than producing in-house.\n <\/div>\n <div class=\"bp-stats\">\n <div class=\"bp-stat-card\">\n <div class=\"stat-number\">40\u201380\/min<\/div>\n <div class=\"stat-label\">Vitesse de production<\/div>\n <\/div>\n <div class=\"bp-stat-card\">\n <div class=\"stat-number\">5\u20138%<\/div>\n <div class=\"stat-label\">Scrap Rate<\/div>\n <\/div>\n <\/div>\n <\/div>\n\n \n \n \n <h2>From Raw Material to Finished Bag \u2014 How Each Type Is Manufactured<\/h2>\n\n <p>Every plastic bag starts the same way \u2014 polymer pellets fed into a hopper \u2014 but diverges dramatically at the forming stage. The machine you choose determines which bag types you can produce, and the quality of that machine determines how competitive your product will be. Understanding this connection turns abstract “types of plastic bags” into concrete production decisions.<\/p>\n\n<img decoding=\"async\" src=\"https:\/\/www.ketegroup.com\/wp-content\/uploads\/2026\/05\/types-of-plastic-bags-for-food-packaging-3.webp\" \n alt=\"types de sacs en plastique pour l'emballage\" \n style=\"width: 512px; height: 384px; max-width: 100%; object-fit: cover; border-radius: 12px; margin: 30px auto; display: block; box-shadow: 10px 10px 60px 0px rgba(210, 221, 224, 0.35); transition: all 0.3s ease; cursor: pointer;\"\n onmouseover=\"this.style.transform='translateY(-5px) scale(1.03)'; this.style.boxShadow='15px 25px 80px 0px rgba(210, 221, 224, 0.45)';\"\n onmouseout=\"this.style.transform='translateY(0) scale(1)'; this.style.boxShadow='10px 10px 60px 0px rgba(210, 221, 224, 0.35)';\">\n\n \n <h3>Film Blowing and Raw Material Preparation \u2014 Where Every Bag Begins<\/h3>\n\n <p>The blown film extrusion process is the universal starting point. Polymer pellets enter a heated barrel where a rotating screw melts and pressurizes them. The molten polymer exits through a circular die, forming a thin tube that is immediately inflated with air \u2014 like blowing up a balloon vertically \u2014 into a bubble 2\u20134 times the die diameter. This blow-up ratio (BUR) is a critical parameter: high BUR strengthens the film in the transverse direction by stretching molecules sideways; low BUR favors machine-direction strength.<\/p>\n\n <p>Cooling air from an external ring solidifies the bubble, which then passes through collapsing frames and nip rollers into a flat lay-flat tube wound onto rolls. Modern lines with internal bubble cooling (IBC) can boost output by 30\u201350% and significantly improve thickness uniformity \u2014 typically paying back the investment within 12 months through higher throughput and lower scrap.<\/p>\n\n <p>The material matters at this stage. HDPE needs slower cooling rates (30\u201380 m\/min line speed) due to its high crystallinity. LDPE runs faster (50\u2013150 m\/min). LLDPE demands higher melt temperatures and more motor torque. Multi-layer coextrusion lines \u2014 running three or more extruders into a single die \u2014 can combine different materials into one film: an outer LDPE layer for printability, a middle LLDPE layer for strength, and an inner EVA layer for low-temperature heat-seal performance. The energy cost runs 40\u201360% higher than a single-layer line, but the film performance gain justifies it for demanding applications.<\/p>\n\n \n \n \n <div class=\"bp-4-process\">\n <div class=\"bp-header\">\n <svg viewbox=\"0 0 24 24\" width=\"24\" height=\"24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);\">\n <circle cx=\"12\" cy=\"12\" r=\"3\"\/>\n <path d=\"M19.4 15a1.65 1.65 0 0 0 .33 1.82l.06.06a2 2 0 0 1 0 2.83 2 2 0 0 1-2.83 0l-.06-.06a1.65 1.65 0 0 0-1.82-.33 1.65 1.65 0 0 0-1 1.51V21a2 2 0 0 1-2 2 2 2 0 0 1-2-2v-.09A1.65 1.65 0 0 0 9 19.4a1.65 1.65 0 0 0-1.82.33l-.06.06a2 2 0 0 1-2.83 0 2 2 0 0 1 0-2.83l.06-.06A1.65 1.65 0 0 0 4.68 15a1.65 1.65 0 0 0-1.51-1H3a2 2 0 0 1-2-2 2 2 0 0 1 2-2h.09A1.65 1.65 0 0 0 4.6 9a1.65 1.65 0 0 0-.33-1.82l-.06-.06a2 2 0 0 1 0-2.83 2 2 0 0 1 2.83 0l.06.06A1.65 1.65 0 0 0 9 4.68a1.65 1.65 0 0 0 1-1.51V3a2 2 0 0 1 2-2 2 2 0 0 1 2 2v.09a1.65 1.65 0 0 0 1 1.51 1.65 1.65 0 0 0 1.82-.33l.06-.06a2 2 0 0 1 2.83 0 2 2 0 0 1 0 2.83l-.06.06A1.65 1.65 0 0 0 19.4 9a1.65 1.65 0 0 0 1.51 1H21a2 2 0 0 1 2 2 2 2 0 0 1-2 2h-.09a1.65 1.65 0 0 0-1.51 1z\"\/>\n <\/svg>\n <span class=\"bp-label\">The Process<\/span>\n <\/div>\n <div class=\"bp-flow\">\n <div class=\"bp-flow-step\">\n <div class=\"step-circle\">1<\/div>\n <div class=\"step-label-wrap\">\n <div class=\"step-label\">Feed<\/div>\n <div class=\"step-sub\">pellets → hopper<\/div>\n <\/div>\n <\/div>\n <div class=\"bp-flow-arrow\">\n <svg viewbox=\"0 0 24 24\" width=\"20\" height=\"20\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\">\n <line x1=\"5\" y1=\"12\" x2=\"19\" y2=\"12\"\/>\n <polyline points=\"12 5 19 12 12 19\"\/>\n <\/svg>\n <\/div>\n <div class=\"bp-flow-step\">\n <div class=\"step-circle\">2<\/div>\n <div class=\"step-label-wrap\">\n <div class=\"step-label\">Melt<\/div>\n <div class=\"step-sub\">screw + heat<\/div>\n <\/div>\n <\/div>\n <div class=\"bp-flow-arrow\">\n <svg viewbox=\"0 0 24 24\" width=\"20\" height=\"20\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\">\n <line x1=\"5\" y1=\"12\" x2=\"19\" y2=\"12\"\/>\n <polyline points=\"12 5 19 12 12 19\"\/>\n <\/svg>\n <\/div>\n <div class=\"bp-flow-step\">\n <div class=\"step-circle\">3<\/div>\n <div class=\"step-label-wrap\">\n <div class=\"step-label\">Blow<\/div>\n <div class=\"step-sub\">die → bubble, BUR 2\u20134:1<\/div>\n <\/div>\n <\/div>\n <div class=\"bp-flow-arrow\">\n <svg viewbox=\"0 0 24 24\" width=\"20\" height=\"20\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\">\n <line x1=\"5\" y1=\"12\" x2=\"19\" y2=\"12\"\/>\n <polyline points=\"12 5 19 12 12 19\"\/>\n <\/svg>\n <\/div>\n <div class=\"bp-flow-step\">\n <div class=\"step-circle\">4<\/div>\n <div class=\"step-label-wrap\">\n <div class=\"step-label\">Wind<\/div>\n <div class=\"step-sub\">collapse → roll<\/div>\n <\/div>\n <\/div>\n <\/div>\n <div class=\"bp-caption\">IBC-equipped lines boost output 30\u201350% and typically pay back within 12 months.<\/div>\n <\/div>\n\n \n <h3>Bag Forming Processes by Type \u2014 How Different Machines Shape Different Bags<\/h3>\n\n <p>This is where the paths diverge, and where the connection between bag type and production equipment becomes concrete.<\/p>\n\n <p>UN <strong>T-shirt bag machine<\/strong> takes the printed or unprinted roll stock through a sequence of stations: unwinding → bottom sealing → handle die-cutting → individual bag cutting → stacking and counting. Production speed runs 120\u2013250 bags per minute on twin-line configurations. The die-cutting station is the critical differentiator \u2014 it creates the integrated handles that define the T-shirt format.<\/p>\n\n <p>UN <strong>flat bag \/ bottom-seal machine<\/strong> is simpler and faster: unwind → bottom seal bar → cut-off knife → stack. With no handle station to slow things down, speeds reach 250\u2013500 bags per minute. Side-seal variants seal along the edges instead of the bottom, producing bags better suited to automated filling lines.<\/p>\n\n <p>UN <strong>zipper bag machine<\/strong> adds a zipper insertion and heat-sealing station between unwinding and bag forming. This station feeds pre-formed zipper profile (LDPE or PP, matched to bag body material) into position between the film layers, where heated bars bond it in place. The added complexity drops line speed to 100\u2013150 bags per minute and increases scrap rates to 3\u20135%.<\/p>\n\n <p>UN <strong>stand-up pouch machine<\/strong> is the most complex of the group. It handles multiple roll stocks simultaneously (outer print layer, barrier layer, inner seal layer), forms the bottom gusset, executes multi-side sealing, and often integrates a zipper station as well. Speeds drop to 40\u201380 pouches per minute. Scrap rates of 5\u20138% are normal and reflect the complexity of coordinating multiple material webs and seal stations.<\/p>\n\n <p>The servo-versus-mechanical distinction matters across all machine types. Servo-driven machines use programmable motors for each motion axis, achieving positioning accuracy of \u00b10.1 mm and enabling quick changeovers between bag sizes via touchscreen recipe selection. Mechanical cam-driven machines are cheaper to buy but deliver \u00b11.5 mm accuracy and require physical cam changes to switch bag dimensions \u2014 a process that can take hours. For factories that change bag sizes frequently, servo is usually the better long-term investment despite the higher upfront cost.<\/p>\n\n <p>For anyone entering bag production, the equipment decision chain is straightforward: first, determine your target bag type (selling to supermarkets means T-shirt bags; selling to food brands means zipper or stand-up pouches); second, match your budget and volume expectations to machine class; third, consider whether servo flexibility justifies the premium. Equipment manufacturers who specialize in multi-type bag making lines \u2014 such as KETE GROUP, whose product range spans T-shirt bag machines, flat bag machines, and zipper bag systems \u2014 can provide the technical guidance to navigate this decision, but the strategic choice of which bag types to produce should always come first.<\/p>\n\n \n \n \n <div class=\"bp-5-cta\">\n <div class=\"cta-icon\">\n <svg viewbox=\"0 0 24 24\" width=\"32\" height=\"32\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:#FFFFFF;opacity:0.9;\">\n <circle cx=\"12\" cy=\"12\" r=\"10\"\/>\n <path d=\"M9.09 9a3 3 0 0 1 5.83 1c0 2-3 3-3 3\"\/>\n <line x1=\"12\" y1=\"17\" x2=\"12.01\" y2=\"17\"\/>\n <\/svg>\n <\/div>\n <div class=\"cta-title\">Not Sure Which Equipment Fits Your Target Bag Type?<\/div>\n <div class=\"cta-subtitle\">Get technical guidance matched to your production goals \u2014 from a single machine to a complete line.<\/div>\n <a class=\"cta-btn\" href=\"https:\/\/www.ketegroup.com\/fr\/contact\/\">Request Equipment Guidance<\/a>\n <\/div>\n\n \n <h3>Quality Control and Thickness Standards \u2014 What Separates Good Bags from Bad<\/h3>\n\n <p>For B2B buyers, quality control is the conversation that happens after the price negotiation \u2014 but before the purchase order. A bag that fails in the field costs far more than the cents saved on a cheaper supplier.<\/p>\n\n <p>Thickness tolerance is the most basic metric. \u00b110% of nominal thickness is the industry baseline; \u00b15% indicates a supplier with tight process control. Thickness variation beyond 15% causes downstream problems: inconsistent print registration, unreliable seal strength, and bags that fail unpredictably under load.<\/p>\n\n <p>Key laboratory tests include tensile strength (<a href=\"https:\/\/www.astm.org\/d0882-18.html\" rel=\"nofollow\">ASTM D882<\/a> \u2014 25.4 mm wide specimen, 50 mm gauge length, 500 mm\/min test speed), Dart Drop Impact (<a href=\"https:\/\/www.astm.org\/d1709-22.html\" rel=\"nofollow\">ASTM D1709<\/a> \u2014 measuring the energy required to cause failure under specified conditions), and heat seal strength (<a href=\"https:\/\/www.astm.org\/f0088-21.html\" rel=\"nofollow\">ASTM F88<\/a> \u2014 minimum 15 N per 25 mm width for food-grade packaging). The coefficient of friction (COF, <a href=\"https:\/\/www.astm.org\/d1894-14.html\" rel=\"nofollow\">ASTM D1894<\/a>) should fall between 0.2 and 0.4 for bags running on automated packing lines \u2014 too slippery and they slide off conveyors; too tacky and they jam.<\/p>\n\n <p>Each bag type has its characteristic defects. T-shirt bags suffer from asymmetric handles when die-cutting alignment drifts. Zipper bags fail when the zipper profile delaminates from the film \u2014 a bonding problem traceable to insufficient sealing temperature or pressure. Stand-up pouches leak at the bottom gusset corner seals, where three or four material layers must fuse perfectly in a single sealing cycle. A practical incoming inspection checklist \u2014 random sample of 10 bags, measure thickness at 3 points each, load-test the handles, peel-test the seals, and rub-test any printing \u2014 catches most problems before they reach the customer.<\/p>\n\n \n \n \n <div class=\"bp-6-checklist\">\n <div class=\"bp-accent-bar\"><\/div>\n <div class=\"bp-content\">\n <div class=\"bp-header\">\n <svg viewbox=\"0 0 24 24\" width=\"20\" height=\"20\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);\">\n <path d=\"M16 4h2a2 2 0 0 1 2 2v14a2 2 0 0 1-2 2H6a2 2 0 0 1-2-2V6a2 2 0 0 1 2-2h2\"\/>\n <rect x=\"8\" y=\"2\" width=\"8\" height=\"4\" rx=\"1\" ry=\"1\"\/>\n <path d=\"M9 14l2 2 4-4\"\/>\n <\/svg>\n <span class=\"bp-label\">Quick Inspection Checklist<\/span>\n <\/div>\n <div class=\"bp-item\">\n <svg viewbox=\"0 0 24 24\" width=\"16\" height=\"16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);flex-shrink:0;\">\n <path d=\"M22 11.08V12a10 10 0 1 1-5.93-9.14\"\/>\n <polyline points=\"22 4 12 14.01 9 11.01\"\/>\n <\/svg>\n <span>Measure thickness at 3 points on 10 random bags<\/span>\n <\/div>\n <div class=\"bp-item\">\n <svg viewbox=\"0 0 24 24\" width=\"16\" height=\"16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);flex-shrink:0;\">\n <path d=\"M22 11.08V12a10 10 0 1 1-5.93-9.14\"\/>\n <polyline points=\"22 4 12 14.01 9 11.01\"\/>\n <\/svg>\n <span>Load-test handles with rated weight for 30 seconds<\/span>\n <\/div>\n <div class=\"bp-item\">\n <svg viewbox=\"0 0 24 24\" width=\"16\" height=\"16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);flex-shrink:0;\">\n <path d=\"M22 11.08V12a10 10 0 1 1-5.93-9.14\"\/>\n <polyline points=\"22 4 12 14.01 9 11.01\"\/>\n <\/svg>\n <span>Peel-test heat seals \u2014 failure at seal line = over-sealing<\/span>\n <\/div>\n <div class=\"bp-item\">\n <svg viewbox=\"0 0 24 24\" width=\"16\" height=\"16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);flex-shrink:0;\">\n <path d=\"M22 11.08V12a10 10 0 1 1-5.93-9.14\"\/>\n <polyline points=\"22 4 12 14.01 9 11.01\"\/>\n <\/svg>\n <span>Rub-test printed surface with dry cloth (10 passes)<\/span>\n <\/div>\n <div class=\"bp-item\">\n <svg viewbox=\"0 0 24 24\" width=\"16\" height=\"16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);flex-shrink:0;\">\n <path d=\"M22 11.08V12a10 10 0 1 1-5.93-9.14\"\/>\n <polyline points=\"22 4 12 14.01 9 11.01\"\/>\n <\/svg>\n <span>Check zipper opening force (target: 5\u201315 N)<\/span>\n <\/div>\n <\/div>\n <\/div>\n\n \n \n \n <h2>Choosing the Right Plastic Bag \u2014 Application Matching Guide<\/h2>\n\n <p>The previous sections gave you the full technical picture. This section reorganizes that information around your actual use case. Find your application in the left column; the rest of the row tells you what to buy.<\/p>\n\n <div class=\"table-wrapper\">\n <table>\n <thead>\n <tr>\n <th>Application<\/th>\n <th>Recommended Material<\/th>\n <th>Recommended Bag Type<\/th>\n <th>Typical Thickness<\/th>\n <th>Principales consid\u00e9rations<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr>\n <td>Supermarket \/ retail checkout<\/td>\n <td>PEHD<\/td>\n <td>Sac \u00e0 t-shirt<\/td>\n <td>15\u201325 \u00b5m<\/td>\n <td>Lowest cost per unit; holds 3\u20135 kg; check local single-use plastic regulations<\/td>\n <\/tr>\n <tr>\n <td>Boutique \/ fashion retail<\/td>\n <td>LDPE<\/td>\n <td>Die-Cut Handle or Soft Loop<\/td>\n <td>40\u201360 \u00b5m<\/td>\n <td>Brand feel and transparency matter; printing quality is a purchase driver<\/td>\n <\/tr>\n <tr>\n <td>Bread, pastries, bakery<\/td>\n <td>LDPE<\/td>\n <td>Flat \/ Bottom-Seal<\/td>\n <td>25\u201335 \u00b5m<\/td>\n <td>Food safety certification required; transparency for product visibility<\/td>\n <\/tr>\n <tr>\n <td>Frozen foods (vegetables, meat, seafood)<\/td>\n <td>LLDPE + LDPE blend<\/td>\n <td>Flat \/ Zipper Bag<\/td>\n <td>50\u201375 \u00b5m<\/td>\n <td>Cold-temperature impact resistance critical; puncture resistance for bone-in products<\/td>\n <\/tr>\n <tr>\n <td>Snacks, confectionery, coffee (shelf display)<\/td>\n <td>BOPP or PET\/PE laminate<\/td>\n <td>Sachet \u00e0 fond plat<\/td>\n <td>60\u2013100 \u00b5m (multi-layer)<\/td>\n <td>Oxygen barrier essential for shelf life; print quality drives purchase decisions<\/td>\n <\/tr>\n <tr>\n <td>Industrial parts, hardware, heavy goods<\/td>\n <td>HDPE or LLDPE<\/td>\n <td>Flat \/ Gusseted<\/td>\n <td>75\u2013150 \u00b5m<\/td>\n <td>Puncture and tear resistance; load capacity 10\u201325 kg<\/td>\n <\/tr>\n <tr>\n <td>Medical device \/ sterilization<\/td>\n <td>PP or HDPE<\/td>\n <td>Flat \/ Self-Seal<\/td>\n <td>50\u2013100 \u00b5m<\/td>\n <td>Sterilization method compatibility (EtO, gamma, steam); no fiber shedding<\/td>\n <\/tr>\n <tr>\n <td>Waste disposal (household)<\/td>\n <td>LDPE + LLDPE blend<\/td>\n <td>T-Shirt \/ Drawstring<\/td>\n <td>30\u201350 \u00b5m<\/td>\n <td>Tear resistance for irregular waste; drawstring convenience for kitchen use<\/td>\n <\/tr>\n <tr>\n <td>Waste disposal (industrial \/ construction)<\/td>\n <td>LDPE + LLDPE blend<\/td>\n <td>Flat \/ Gusseted<\/td>\n <td>80\u2013150 \u00b5m<\/td>\n <td>Heavy puncture resistance; consider recycled content (PCR) for sustainability mandates<\/td>\n <\/tr>\n <tr>\n <td>E-commerce shipping<\/td>\n <td>LDPE or LLDPE<\/td>\n <td>Poly Mailer \/ Flat<\/td>\n <td>50\u201380 \u00b5m<\/td>\n <td>Opaque for privacy; self-seal adhesive strip; tamper-evident optional<\/td>\n <\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p><strong>How to use this table:<\/strong> Start with your product \u2014 what are you packing, how heavy is it, what shape? Then check display requirements \u2014 does the customer need to see the product? Finally, confirm regulatory and budget constraints. Common mistakes to avoid: choosing by price alone (a cheaper thinner bag that tears means higher total cost from returns and damage), ignoring filling-line compatibility (wrong COF = jammed automation), and overlooking destination-market regulations (the EU’s EN 13432 composting standard has no equivalent in many markets where “biodegradable” claims remain unregulated).<\/p>\n\n \n \n \n <h2>Sustainable and Eco-Friendly Plastic Bag Alternatives \u2014 What Actually Works<\/h2>\n\n <p>Sustainability in plastic bags is a landscape of genuine innovation, marketing hype, and well-intentioned solutions that fail in the real world. Here is an honest assessment of what is available, what the certifications actually mean, and where the trade-offs lie.<\/p>\n\n <div class=\"table-wrapper\">\n <table>\n <thead>\n <tr>\n <th>Solution<\/th>\n <th>Material Base<\/th>\n <th>Degradation Conditions<\/th>\n <th>Degradation Time<\/th>\n <th>Certification<\/th>\n <th>Limitation principale<\/th>\n <th>Cost vs. Conventional PE<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr>\n <td>PLA (Polylactic Acid)<\/td>\n <td>Corn starch \/ sugarcane<\/td>\n <td>Industrial compost (58\u00b0C, high humidity)<\/td>\n <td>3 \u00e0 6 mois<\/td>\n <td>EN 13432, ASTM D6400<\/td>\n <td>Glass transition at 55\u201360\u00b0C \u2014 cannot handle hot fill; brittle; contaminates PE recycling streams<\/td>\n <td>3 \u00e0 5 fois\u00d7<\/td>\n <\/tr>\n <tr>\n <td>PBAT + PLA blend<\/td>\n <td>Fossil-based biodegradable polyester + PLA<\/td>\n <td>Industrial compost<\/td>\n <td>3 \u00e0 6 mois<\/td>\n <td>EN 13432<\/td>\n <td>More flexible than pure PLA; still requires industrial composting infrastructure<\/td>\n <td>2\u20134\u00d7<\/td>\n <\/tr>\n <tr>\n <td>Oxo-degradable (EPI additive)<\/td>\n <td>Conventional PE + metal-salt additive<\/td>\n <td>Light\/heat triggers fragmentation<\/td>\n <td>18\u201360 months to fragment<\/td>\n <td>No recognized international standard<\/td>\n <td>Fragments into microplastics \u2014 does not biodegrade; banned in EU Single-Use Plastics Directive<\/td>\n <td>1.2\u20131.5\u00d7<\/td>\n <\/tr>\n <tr>\n <td>Recycl\u00e9 apr\u00e8s consommation (PCR)<\/td>\n <td>Recycled HDPE\/LDPE re-pelletized<\/td>\n <td>N\/A (circular economy, not degradation)<\/td>\n <td>N\/A<\/td>\n <td>GRS (Global Recycled Standard)<\/td>\n <td>Grayish color, potential odor, 10\u201320% mechanical property loss; food-contact restrictions vary by jurisdiction<\/td>\n <td>1.2\u20131.8\u00d7<\/td>\n <\/tr>\n <tr>\n <td>Paper bags<\/td>\n <td>Kraft paper<\/td>\n <td>Natural degradation<\/td>\n <td>1\u20132 months<\/td>\n <td>FSC (forestry sourcing)<\/td>\n <td>No water resistance; far lower load capacity than PE; production uses 4\u00d7 the energy and 2\u00d7 the water of PE bags<\/td>\n <td>2\u20133\u00d7<\/td>\n <\/tr>\n <tr>\n <td>Downgauging (lightweighting)<\/td>\n <td>Conventional PE, thinner<\/td>\n <td>N\/A<\/td>\n <td>N\/A<\/td>\n <td>No special certification needed<\/td>\n <td>Physical performance limits constrain thinning; currently the most pragmatic “sustainable” path for industrial users<\/td>\n <td>0.8\u20130.9\u00d7<\/td>\n <\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p><strong>EN 13432<\/strong> \u2014 the European standard for industrially compostable packaging \u2014 requires four things: \u226590% biodegradation within 6 months at 58\u00b0C (<a href=\"https:\/\/www.iso.org\/standard\/78712.html\" rel=\"nofollow\">EN ISO 14855-1<\/a>), disintegration to \u226410% fragments larger than 2 mm within 12 weeks, no negative effect on the composting process, and no ecotoxicity in the final compost (verified by plant growth tests per OECD 208).<\/p>\n\n <p>The uncomfortable truth: industrial composting conditions \u2014 58\u00b0C, 50\u201360% humidity, continuous aeration \u2014 are not backyard compost bin conditions. If a PLA bag is sold into a market without industrial composting infrastructure, it will persist in the environment for years, functionally identical to a conventional plastic bag from a litter perspective. Before switching to any “biodegradable” option, verify that your end market actually has the collection and processing infrastructure to handle it.<\/p>\n\n <p>For most industrial and B2B applications today, <strong>downgauging<\/strong> \u2014 using less material to achieve the same performance through better resin grades and process control \u2014 is the most cost-effective and genuinely impactful sustainability move. It reduces material consumption, lowers transport weight, and cuts carbon footprint without requiring new recycling or composting infrastructure that may not exist.<\/p>\n\n \n \n \n <h2>Putting It All Together<\/h2>\n\n <p>You do not need to memorize every polymer density or machine speed to make a good plastic bag decision. What you do need is a clear mental model: material sets the floor for performance and cost, design determines what the bag can actually do, and the manufacturing process decides whether you can make it yourself or need to buy from a converter.<\/p>\n\n <p>If you take away one thing from this guide, let it be this: the question is never just “which type of plastic bag?” It is “which material, in which structure, made on which equipment, for which market?” Each answer narrows the field. A frozen food brand needs LLDPE \u2014 not because it is the cheapest, but because cold-temperature impact resistance is non-negotiable when a bag of frozen chicken hits a warehouse floor. A coffee roaster choosing between a flat bag and a stand-up pouch is really choosing between looking like a commodity and looking like a brand. A factory owner deciding between a T-shirt bag machine and a zipper bag machine is betting on which customers they want to serve for the next ten years.<\/p>\n\n <p>The plastic bag is a simple product. Getting it right is not. That is why understanding the full picture \u2014 materials, design, manufacturing \u2014 pays for itself in better decisions.<\/p>\n\n \n \n \n <div class=\"bp-7-cta\">\n <svg viewbox=\"0 0 24 24\" width=\"32\" height=\"32\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-footer-text);\">\n <path d=\"M16.5 9.4 7.55 4.24a1 1 0 0 0-1.1 0L2 7.08\"\/>\n <path d=\"M21 16V8a2 2 0 0 0-1-1.73l-7-4a2 2 0 0 0-2 0l-7 4A2 2 0 0 0 3 8v8a2 2 0 0 0 1 1.73l7 4a2 2 0 0 0 2 0l7-4A2 2 0 0 0 21 16z\"\/>\n <polyline points=\"3.29 7 12 12 20.71 7\"\/>\n <line x1=\"12\" y1=\"22\" x2=\"12\" y2=\"12\"\/>\n <\/svg>\n <div class=\"cta-title\">Ready to Build Your Bag Production Line?<\/div>\n <div class=\"cta-subtitle\">KETE GROUP provides bag making machines for T-shirt bags, flat bags, zipper bags, and more \u2014 with technical support from consultation to after-sales.<\/div>\n <div class=\"cta-chips\">\n <span class=\"cta-chip\">Multi-Type Machines<\/span>\n <span class=\"cta-chip\">Custom Configurations<\/span>\n <span class=\"cta-chip\">Global Support<\/span>\n <\/div>\n <a class=\"cta-btn\" href=\"https:\/\/www.ketegroup.com\/fr\/contact\/\">Parler \u00e0 un ing\u00e9nieur<\/a>\n <\/div>\n\n \n \n \n <hr>\n\n <p style=\"font-size:14px;color:var(--color-text-secondary);margin-bottom:8px;font-weight:600;\">R\u00e9f\u00e9rences<\/p>\n <ul style=\"font-size:13px;color:var(--color-text-secondary);padding-left:1.2em;list-style:disc outside;\">\n <li>ASTM International. “ASTM D4976-12a(2020) \u2014 Standard Specification for Polyethylene Plastics Molding and Extrusion Materials.” 2020. <a href=\"https:\/\/www.astm.org\/d4976-12ar20.html\" rel=\"nofollow\">https:\/\/www.astm.org\/d4976-12ar20.html<\/a><\/li>\n <li>British Plastics Federation. “Standards for Compostability \u2014 EN 13432.” <a href=\"https:\/\/www.bpf.co.uk\/Topics\/Standards_for_compostability.aspx\" rel=\"nofollow\">https:\/\/www.bpf.co.uk\/Topics\/Standards_for_compostability.aspx<\/a><\/li>\n <li>ASTM International. “ASTM D882-18 \u2014 Standard Test Method for Tensile Properties of Thin Plastic Sheeting.” <a href=\"https:\/\/www.astm.org\/d0882-18.html\" rel=\"nofollow\">https:\/\/www.astm.org\/d0882-18.html<\/a><\/li>\n <li>ASTM International. “ASTM D1709-22 \u2014 Standard Test Methods for Impact Resistance of Plastic Film by the Free-Falling Dart Method.” <a href=\"https:\/\/www.astm.org\/d1709-22.html\" rel=\"nofollow\">https:\/\/www.astm.org\/d1709-22.html<\/a><\/li>\n <li>ASTM International. “ASTM F88-21 \u2014 Standard Test Method for Seal Strength of Flexible Barrier Materials.” <a href=\"https:\/\/www.astm.org\/f0088-21.html\" rel=\"nofollow\">https:\/\/www.astm.org\/f0088-21.html<\/a><\/li>\n <li>ASTM International. “ASTM D1894-14 \u2014 Standard Test Method for Static and Kinetic Coefficients of Friction of Plastic Film and Sheeting.” <a href=\"https:\/\/www.astm.org\/d1894-14.html\" rel=\"nofollow\">https:\/\/www.astm.org\/d1894-14.html<\/a><\/li>\n <li>ISO. “ISO 14855-1:2012 \u2014 Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions.” <a href=\"https:\/\/www.iso.org\/standard\/78712.html\" rel=\"nofollow\">https:\/\/www.iso.org\/standard\/78712.html<\/a><\/li>\n <li>KETE GROUP LIMITED. Company website. <a href=\"https:\/\/www.ketegroup.com\/fr\">https:\/\/www.ketegroup.com\/<\/a><\/li>\n <li>KETE GROUP LIMITED. Contact page. <a href=\"https:\/\/www.ketegroup.com\/fr\/contact\/\">https:\/\/www.ketegroup.com\/contact\/<\/a><\/li>\n <\/ul>\n\n<\/article>\n\n\n<script type=\"application\/ld+json\">{\n \"@context\": \"https:\\\/\\\/schema.org\",\n \"@type\": \"Article\",\n \"headline\": \"Types of Plastic Bags: How Materials, Design, and Manufacturing Shape Your Options\",\n \"description\": \"A comprehensive guide to plastic bag types covering materials (HDPE, LDPE, LLDPE, PP), structural designs, manufacturing processes, and application matching for B2B buyers and packaging professionals.\",\n \"author\": {\n \"@type\": \"Organization\",\n \"name\": \"KETE GROUP\"\n },\n \"about\": {\n \"@type\": \"Thing\",\n \"name\": \"plastic bag manufacturing\",\n \"description\": \"Types of plastic bags, polymer properties, bag design and structures, and manufacturing equipment\"\n }\n}<\/script>\n\n<\/div>\n<\/body>\n<\/html>","protected":false},"excerpt":{"rendered":"<p>Types of Plastic Bags: How Materials, Design, and Manufacturing Shape Your Options Walk into any supermarket, and you will handle at least three different types of plastic bags before you reach the checkout \u2014 the transparent produce bag, the crinkly shopping bag at the register, and maybe a resealable freezer bag waiting at home. They […]<\/p>","protected":false},"author":1,"featured_media":14838,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"28","_seopress_titles_title":"Types of Plastic Bags: Materials, Uses & Machine Options","_seopress_titles_desc":"Discover the exact types of plastic bags your business needs. 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{"id":14825,"date":"2024-09-11T11:24:39","date_gmt":"2024-09-11T03:24:39","guid":{"rendered":"https:\/\/www.ketegroup.com\/?p=14825"},"modified":"2026-08-07T10:17:55","modified_gmt":"2026-08-07T02:17:55","slug":"types-of-plastic-bags-for-packaging","status":"publish","type":"post","link":"https:\/\/www.ketegroup.com\/fr\/types-de-sacs-en-plastique-pour-lemballage\/","title":{"rendered":"Types of Plastic Bags: How Materials, Design, and Manufacturing Shape Your Options"},"content":{"rendered":"\n\n\n\n\nTypes of Plastic Bags: How Materials, Design, and Manufacturing Shape Your Options<\/title>\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n<link href=\"https:\/\/fonts.googleapis.com\/css2?family=Hammersmith+One&family=Open+Sans:wght@300..800&display=swap\" rel=\"stylesheet\">\n<\/head>\n<body style=\"margin:0;background:#FFFFFF;\">\n\n<div class=\"bd-post\">\n\n<style>\n\/* ==========================================================================\n BD-POST \u2014 TYPES OF PLASTIC BAGS (Variant 1)\n Design: blog-designer-present-v3\n Scope: every selector prefixed with .bd-post\n ========================================================================== *\/\n\n.bd-post {\n \/* ---- Palette ---- *\/\n --color-primary: #136AD5;\n --color-primary-hover: #0072FF;\n --color-primary-dark: #245AC5;\n --color-accent: #FF6A00;\n --color-accent-dark: #B84D00;\n --color-text: #333333;\n --text-primary: #333333;\n --accent-text: #0F4FA0;\n --color-text-secondary: #666666;\n --color-text-tertiary: #999999;\n --color-heading: #333333;\n --color-white: #FFFFFF;\n --color-near-black: #031008;\n --color-bg-white: #FFFFFF;\n --color-bg-light: #F6F6F6;\n --color-bg-off-white: #FAFAFA;\n --color-bg-cool: #F5F8FA;\n --color-footer-text: #99BBE6;\n --color-footer-muted: #9EACBD;\n --color-neutral-card: #F2F6FB;\n --color-neutral-border: #D7E7F2;\n --color-accent-text-grade: #0D4A99;\n\n \/* ---- Typography ---- *\/\n --font-body: \"Open Sans\", Sans-serif;\n --font-heading-display: \"Hammersmith One\", Sans-serif;\n --font-heading: \"Open Sans\", Sans-serif;\n\n \/* ---- Spacing ---- *\/\n --gap-attach: 16px;\n --gap-normal: 32px;\n --gap-section: 48px;\n --pad-compact: 16px;\n --pad-standard: 24px;\n\n \/* ---- Border radius ---- *\/\n --radius-sm: 3px;\n --radius-md: 6px;\n\n \/* ---- Shadows ---- *\/\n --shadow-subtle: 0px 0px 10px 0px rgba(0,0,0,0.05);\n --shadow-medium: 0px 0px 12px 0px rgba(0,0,0,0.15);\n\n \/* ---- Defaults ---- *\/\n font-family: var(--font-body);\n font-size: 16px;\n font-weight: 400;\n line-height: 1.6;\n color: var(--color-text);\n -webkit-font-smoothing: antialiased;\n -moz-osx-font-smoothing: grayscale;\n}\n\n\/* ---- Container ---- *\/\n.bd-post-article {\n width: 100%;\n max-width: none;\n margin: 0 auto;\n padding: 0;\n box-sizing: border-box;\n}\n\n\/* ---- Headings ---- *\/\n.bd-post h2 {\n font-family: var(--font-heading-display);\n font-size: 28px;\n font-weight: 400;\n line-height: 1.2;\n color: var(--text-primary);\n margin: 48px 0 16px 0;\n transition: color .2s ease-out, transform .2s ease-out;\n}\n\n.bd-post h2:hover {\n color: var(--accent-text);\n transform: translateX(2px);\n}\n\n.bd-post h3 {\n font-family: var(--font-heading);\n font-size: 20px;\n font-weight: 600;\n line-height: 1.2;\n color: var(--text-primary);\n margin: 32px 0 12px 0;\n}\n\n\/* The page template supplies the H1. 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flex-direction: column;\n gap: 6px;\n}\n\n.bd-post .bp-1-tip .bp-header {\n display: flex;\n align-items: center;\n gap: 6px;\n}\n\n.bd-post .bp-1-tip .bp-header svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-1-tip .bp-label {\n font-size: 14px;\n font-weight: 600;\n color: var(--color-text-secondary);\n letter-spacing: 0.5px;\n text-transform: uppercase;\n}\n\n.bd-post .bp-1-tip .bp-body {\n font-size: 14px;\n color: var(--color-text);\n}\n\n.bd-post .bp-1-tip .bp-dim-list {\n display: inline;\n font-size: 14px;\n color: var(--color-text);\n}\n\n.bd-post .bp-1-tip .bp-dim-list .dim-item {\n font-weight: 600;\n}\n\n.bd-post .bp-1-tip .bp-dim-list .dim-desc {\n font-weight: 400;\n}\n\n\/* ----- BP-2 : Polymer Comparison (table) ----- *\/\n.bd-post .bp-2-compare {\n display: flex;\n flex-direction: column;\n gap: 16px;\n padding: var(--pad-standard);\n margin-bottom: var(--gap-section);\n background-color: var(--color-neutral-card);\n border: 1px solid var(--color-neutral-border);\n border-radius: var(--radius-md);\n}\n\n.bd-post .bp-2-compare .bp-header {\n display: flex;\n align-items: center;\n gap: 8px;\n}\n\n.bd-post .bp-2-compare .bp-header svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-2-compare .bp-label {\n font-size: 14px;\n font-weight: 600;\n color: var(--color-text-secondary);\n letter-spacing: 0.5px;\n text-transform: uppercase;\n}\n\n.bd-post .bp-2-compare .bp-table {\n width: 100%;\n border-collapse: collapse;\n font-size: 14px;\n}\n\n.bd-post .bp-2-compare .bp-table th {\n background-color: var(--color-bg-cool);\n font-weight: 600;\n color: var(--color-text);\n padding: 8px 10px;\n text-align: left;\n border-bottom: 1px solid var(--color-neutral-border);\n}\n\n.bd-post .bp-2-compare .bp-table td {\n padding: 8px 10px;\n border-bottom: 1px solid var(--color-neutral-border);\n color: var(--color-text);\n vertical-align: top;\n}\n\n.bd-post .bp-2-compare .bp-table tr:last-child td {\n border-bottom: none;\n}\n\n.bd-post .bp-2-compare .bp-table .prop-col {\n font-weight: 600;\n color: var(--color-accent-text-grade);\n white-space: nowrap;\n}\n\n\/* ----- BP-3 : Key Insight (stand-up pouch capital reality) ----- *\/\n.bd-post .bp-3-insight {\n display: flex;\n flex-direction: column;\n gap: 12px;\n padding: var(--pad-standard);\n margin-bottom: var(--gap-section);\n background-color: var(--color-neutral-card);\n border: 1px solid var(--color-neutral-border);\n border-radius: var(--radius-md);\n}\n\n.bd-post .bp-3-insight .bp-header {\n display: flex;\n align-items: center;\n gap: 8px;\n}\n\n.bd-post .bp-3-insight .bp-header svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-3-insight .bp-label {\n font-size: 14px;\n font-weight: 600;\n color: var(--color-accent-dark);\n letter-spacing: 0.5px;\n text-transform: uppercase;\n}\n\n.bd-post .bp-3-insight .bp-body {\n font-size: 15px;\n color: var(--color-text);\n}\n\n.bd-post .bp-3-insight .bp-stats {\n display: flex;\n flex-direction: row;\n gap: 12px;\n}\n\n.bd-post .bp-3-insight .bp-stat-card {\n flex: 1;\n background-color: var(--color-white);\n border: 1px solid var(--color-neutral-border);\n border-radius: 4px;\n padding: 10px 14px;\n text-align: center;\n}\n\n.bd-post .bp-3-insight .bp-stat-card .stat-number {\n font-size: 20px;\n font-weight: 700;\n color: var(--color-accent-text-grade);\n line-height: 1.2;\n}\n\n.bd-post .bp-3-insight .bp-stat-card .stat-label {\n font-size: 13px;\n color: var(--color-text-secondary);\n line-height: 1.4;\n}\n\n\/* ----- BP-4 : Blown Film Process (flow) ----- *\/\n.bd-post .bp-4-process {\n display: flex;\n flex-direction: column;\n gap: 20px;\n padding: var(--pad-standard);\n margin-bottom: var(--gap-normal);\n background-color: var(--color-neutral-card);\n border: 1px solid var(--color-neutral-border);\n border-radius: var(--radius-md);\n}\n\n.bd-post .bp-4-process .bp-header {\n display: flex;\n align-items: center;\n gap: 8px;\n}\n\n.bd-post .bp-4-process .bp-header svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-4-process .bp-label {\n font-size: 14px;\n font-weight: 600;\n color: var(--color-text-secondary);\n letter-spacing: 0.5px;\n text-transform: uppercase;\n}\n\n.bd-post .bp-4-process .bp-flow {\n display: flex;\n flex-direction: row;\n align-items: center;\n gap: 0;\n}\n\n.bd-post .bp-4-process .bp-flow-step {\n flex: 1;\n display: flex;\n flex-direction: column;\n align-items: center;\n gap: 8px;\n text-align: center;\n}\n\n.bd-post .bp-4-process .bp-flow-step .step-circle {\n width: 28px;\n height: 28px;\n background-color: var(--color-primary);\n color: var(--color-white);\n border-radius: 50%;\n display: flex;\n align-items: center;\n justify-content: center;\n font-size: 14px;\n font-weight: 700;\n flex-shrink: 0;\n line-height: 1;\n}\n\n.bd-post .bp-4-process .bp-flow-step .step-label {\n font-size: 13px;\n font-weight: 600;\n color: var(--color-text);\n line-height: 1.3;\n}\n\n.bd-post .bp-4-process .bp-flow-step .step-sub {\n font-size: 12px;\n color: var(--color-text-secondary);\n line-height: 1.3;\n white-space: nowrap;\n}\n\n.bd-post .bp-4-process .bp-flow-arrow {\n flex: 0 0 auto;\n display: flex;\n align-items: center;\n justify-content: center;\n width: 32px;\n height: 28px;\n color: var(--color-text-tertiary);\n}\n\n.bd-post .bp-4-process .bp-flow-arrow svg {\n display: block;\n width: 20px;\n height: 20px;\n}\n\n.bd-post .bp-4-process .bp-caption {\n font-size: 13px;\n color: var(--color-text-secondary);\n font-style: italic;\n text-align: center;\n}\n\n\/* ----- BP-5 : Mid CTA (Accent solid-fill) ----- *\/\n.bd-post .bp-5-cta {\n display: flex;\n flex-direction: column;\n align-items: center;\n text-align: center;\n gap: 16px;\n padding: var(--pad-standard);\n margin-bottom: var(--gap-section);\n background-color: #0A3570;\n border-radius: var(--radius-md);\n color: var(--color-white);\n}\n\n.bd-post .bp-5-cta svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-5-cta .cta-icon {\n opacity: 0.9;\n}\n\n.bd-post .bp-5-cta .cta-title {\n font-size: 22px;\n font-weight: 700;\n color: var(--color-white);\n line-height: 1.3;\n margin: 0;\n}\n\n.bd-post .bp-5-cta .cta-subtitle {\n font-size: 18px;\n font-weight: 700;\n color: #FFFFFF;\n max-width: 480px;\n line-height: 1.5;\n margin: 0;\n}\n\n.bd-post .bp-5-cta .cta-btn {\n display: inline-block;\n background-color: var(--color-white);\n color: var(--color-primary);\n font-size: 16px;\n font-weight: 600;\n padding: 14px 28px;\n border: 2px solid #99BBE6;\n border-radius: var(--radius-md);\n text-decoration: none;\n transition: background-color 0.3s, color 0.3s;\n}\n\n.bd-post .bp-5-cta .cta-btn:hover {\n background-color: #FFFFFF;\n color: var(--color-accent-text-grade);\n}\n\n\/* ----- BP-6 : Incoming Inspection Checklist ----- *\/\n.bd-post .bp-6-checklist {\n display: flex;\n flex-direction: row;\n align-items: flex-start;\n gap: 12px;\n padding: var(--pad-compact);\n margin-bottom: var(--gap-attach);\n background-color: var(--color-neutral-card);\n border: 1px solid var(--color-neutral-border);\n border-radius: var(--radius-md);\n}\n\n.bd-post .bp-6-checklist .bp-accent-bar {\n width: 4px;\n align-self: stretch;\n background-color: var(--color-primary);\n border-radius: 2px;\n flex-shrink: 0;\n}\n\n.bd-post .bp-6-checklist .bp-content {\n flex: 1;\n display: flex;\n flex-direction: column;\n gap: 10px;\n}\n\n.bd-post .bp-6-checklist .bp-header {\n display: flex;\n align-items: center;\n gap: 6px;\n}\n\n.bd-post .bp-6-checklist .bp-header svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-6-checklist .bp-label {\n font-size: 14px;\n font-weight: 600;\n color: var(--color-text-secondary);\n letter-spacing: 0.5px;\n text-transform: uppercase;\n}\n\n.bd-post .bp-6-checklist .bp-item {\n display: flex;\n align-items: flex-start;\n gap: 8px;\n font-size: 14px;\n color: var(--color-text);\n}\n\n.bd-post .bp-6-checklist .bp-item svg {\n flex-shrink: 0;\n display: block;\n margin-top: 2px;\n}\n\n\/* ----- BP-7 : End CTA (Inverse solid-fill) ----- *\/\n.bd-post .bp-7-cta {\n display: flex;\n flex-direction: column;\n align-items: center;\n text-align: center;\n gap: 18px;\n padding: var(--pad-standard);\n margin-bottom: 0;\n background-color: var(--color-near-black);\n border-radius: var(--radius-md);\n color: var(--color-white);\n}\n\n.bd-post .bp-7-cta svg {\n flex-shrink: 0;\n display: block;\n}\n\n.bd-post .bp-7-cta .cta-title {\n font-size: 24px;\n font-weight: 700;\n color: var(--color-white);\n line-height: 1.3;\n margin: 0;\n}\n\n.bd-post .bp-7-cta .cta-subtitle {\n font-size: 16px;\n color: var(--color-footer-muted);\n max-width: 500px;\n line-height: 1.5;\n margin: 0;\n}\n\n.bd-post .bp-7-cta .cta-chips {\n display: flex;\n flex-direction: row;\n flex-wrap: wrap;\n gap: 8px;\n justify-content: center;\n}\n\n.bd-post .bp-7-cta .cta-chip {\n font-size: 12px;\n color: var(--color-footer-text);\n border: 1px solid var(--color-footer-text);\n border-radius: 100px;\n padding: 4px 12px;\n line-height: 1.4;\n}\n\n.bd-post .bp-7-cta .cta-btn {\n display: inline-block;\n background-color: var(--color-primary);\n color: var(--color-white);\n font-size: 16px;\n font-weight: 600;\n padding: 14px 28px;\n border-radius: var(--radius-md);\n text-decoration: none;\n transition: background-color 0.3s, color 0.3s;\n}\n\n.bd-post .bp-7-cta a.cta-btn,\n.bd-post .bp-7-cta a.cta-btn:visited {\n color: #FFFFFF !important;\n}\n\n.bd-post .bp-7-cta .cta-btn:hover {\n background-color: var(--color-white);\n color: var(--color-near-black);\n}\n\n\/* ==========================================================================\n MOTION\n ========================================================================== *\/\n\n@media (prefers-reduced-motion: no-preference) {\n \/* Scroll reveal \u2014 fade up *\/\n @supports (animation-timeline: view()) {\n .bd-post .bp-1-tip,\n .bd-post .bp-2-compare,\n .bd-post .bp-3-insight,\n .bd-post .bp-4-process,\n .bd-post .bp-5-cta,\n .bd-post .bp-6-checklist,\n .bd-post .bp-7-cta {\n animation: bd-fade-up 0.6s ease-out both;\n animation-timeline: view();\n animation-range: entry 0% entry 20%;\n }\n }\n\n \/* Card hover lift on neutral BPs *\/\n .bd-post .bp-1-tip:hover,\n .bd-post .bp-2-compare:hover,\n .bd-post .bp-3-insight:hover,\n .bd-post .bp-4-process:hover,\n .bd-post .bp-6-checklist:hover {\n transform: translateY(-2px);\n box-shadow: var(--shadow-medium);\n transition: transform 0.3s, box-shadow 0.3s;\n }\n\n \/* Link underline \u2014 handled via text-decoration-color transition above *\/\n}\n\n@keyframes bd-fade-up {\n from {\n opacity: 0;\n transform: translateY(12px);\n }\n to {\n opacity: 1;\n transform: translateY(0);\n }\n}\n\n\/* ==========================================================================\n MOBILE (max-width: 768px)\n ========================================================================== *\/\n\n@media (max-width: 768px) {\n .bd-post-article {\n padding: 0 16px;\n }\n\n .bd-post h1 {\n font-size: 34px;\n }\n\n .bd-post h2 {\n font-size: 28px;\n margin-top: 32px;\n margin-bottom: 16px;\n }\n\n .bd-post h3 {\n font-size: 20px;\n margin-top: 24px;\n margin-bottom: 12px;\n }\n\n .bd-post h4 {\n font-size: 18px;\n }\n\n \/* BP margin adjustments *\/\n .bd-post .bp-1-tip,\n .bd-post .bp-6-checklist {\n padding: 12px;\n }\n\n .bd-post .bp-2-compare,\n .bd-post .bp-3-insight,\n .bd-post .bp-4-process,\n .bd-post .bp-5-cta,\n .bd-post .bp-7-cta {\n padding: 18px;\n }\n\n \/* BP-4 flow \u2192 vertical stack *\/\n .bd-post .bp-4-process .bp-flow {\n flex-direction: column;\n gap: 12px;\n }\n\n .bd-post .bp-4-process .bp-flow-step {\n flex: none;\n width: 100%;\n flex-direction: row;\n gap: 12px;\n text-align: left;\n }\n\n .bd-post .bp-4-process .bp-flow-step .step-label-wrap {\n text-align: left;\n }\n\n .bd-post .bp-4-process .bp-flow-arrow {\n transform: rotate(90deg);\n height: auto;\n width: 28px;\n align-self: center;\n }\n\n .bd-post .bp-4-process .bp-flow-step .step-circle {\n flex-shrink: 0;\n }\n\n \/* BP-3 stats stack *\/\n .bd-post .bp-3-insight .bp-stats {\n flex-direction: column;\n }\n\n \/* BP-5 CTA *\/\n .bd-post .bp-5-cta .cta-title {\n font-size: 20px;\n }\n\n \/* BP-7 CTA *\/\n .bd-post .bp-7-cta .cta-title {\n font-size: 22px;\n }\n\n \/* Table font-size *\/\n .bd-post table {\n font-size: 13px;\n }\n\n .bd-post th,\n .bd-post td {\n padding: 8px 10px;\n }\n}\n\n\/* ==========================================================================\n PRINT\n ========================================================================== *\/\n\n@media print {\n .bd-post .bp-5-cta,\n .bd-post .bp-7-cta {\n break-inside: avoid;\n page-break-inside: avoid;\n }\n}\n<\/style>\n\n<article class=\"bd-post-article\">\n\n \n \n \n \n \n \n <p>Walk into any supermarket, and you will handle at least three different types of plastic bags before you reach the checkout \u2014 the transparent produce bag, the crinkly shopping bag at the register, and maybe a resealable freezer bag waiting at home. They all look like “plastic bags,” but they are fundamentally different products: different materials, different structures, and made on entirely different production lines.<\/p>\n\n <p>Understanding those differences matters whether you are a procurement manager choosing packaging for a food brand, a factory owner deciding which bag types to produce, or simply someone who wants to know what you are actually buying. This guide covers every major dimension: the polymers that determine a bag’s feel and performance, the structural designs that dictate how it works, the manufacturing processes behind each type, and the practical question of which bag fits which job.<\/p>\n\n \n \n \n <div class=\"bp-1-tip\">\n <div class=\"bp-accent-bar\"><\/div>\n <div class=\"bp-content\">\n <div class=\"bp-header\">\n <svg viewbox=\"0 0 24 24\" width=\"20\" height=\"20\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);\">\n <circle cx=\"12\" cy=\"12\" r=\"10\"\/>\n <line x1=\"12\" y1=\"16\" x2=\"12\" y2=\"12\"\/>\n <line x1=\"12\" y1=\"8\" x2=\"12.01\" y2=\"8\"\/>\n <\/svg>\n <span class=\"bp-label\">Evaluation Framework<\/span>\n <\/div>\n <div class=\"bp-body\">\n Every material is assessed across four dimensions:\n <span class=\"bp-dim-list\">\n <span class=\"dim-item\">Mechanical<\/span> <span class=\"dim-desc\">(strength\/flexibility)<\/span> ·\n <span class=\"dim-item\">Thermal<\/span> <span class=\"dim-desc\">(melting\/sealing)<\/span> ·\n <span class=\"dim-item\">Optical<\/span> <span class=\"dim-desc\">(clarity\/haze)<\/span> ·\n <span class=\"dim-item\">\u00c9conomique<\/span> <span class=\"dim-desc\">(cost\/processing)<\/span>\n <\/span>\n <\/div>\n <\/div>\n <\/div>\n\n \n \n \n <h2>Material-Based Types \u2014 Understanding Plastic Bag Polymers<\/h2>\n\n <p>The polymer is not just a “material choice” \u2014 it dictates the bag’s feel, strength, temperature tolerance, cost structure, and even which markets you can legally sell into. Before diving into specific materials, here is a four-dimension framework to evaluate any plastic bag polymer: <strong>mechanical performance<\/strong> (strength and flexibility), <strong>thermal behavior<\/strong> (melting point and heat-seal temperature), <strong>optical properties<\/strong> (transparency and haze), and <strong>economics<\/strong> (raw material cost and processing difficulty). Every material covered below is assessed along these four lines.<\/p>\n\n\n<img decoding=\"async\" src=\"https:\/\/www.ketegroup.com\/wp-content\/uploads\/2026\/05\/types-of-plastic-bags-for-food-packaging-1.webp\" \n alt=\"types de sacs en plastique pour l'emballage alimentaire 1\" \n style=\"width: 512px; height: 384px; max-width: 100%; object-fit: cover; border-radius: 12px; margin: 30px auto; display: block; box-shadow: 10px 10px 60px 0px rgba(210, 221, 224, 0.35); transition: all 0.3s ease; cursor: pointer;\"\n onmouseover=\"this.style.transform='translateY(-5px) scale(1.03)'; this.style.boxShadow='15px 25px 80px 0px rgba(210, 221, 224, 0.45)';\"\n onmouseout=\"this.style.transform='translateY(0) scale(1)'; this.style.boxShadow='10px 10px 60px 0px rgba(210, 221, 224, 0.35)';\">\n\n \n <h3>HDPE (High-Density Polyethylene) \u2014 The Workhorse of Plastic Bags<\/h3>\n\n <p>HDPE is the most common plastic bag material on the planet \u2014 and the one you have almost certainly used today. It is the crisp, slightly crinkly, semi-transparent material behind supermarket singlet bags and bin liners.<\/p>\n\n <p>The numbers explain why. HDPE has a density of 0.94\u20130.97 g\/cm\u00b3 and a tensile yield strength of 20\u201330 MPa (<a href=\"https:\/\/www.astm.org\/d4976-12ar20.html\" rel=\"nofollow\">ASTM D4976<\/a>, 2020). It melts at 120\u2013130\u00b0C and crystallizes to 80\u201390%, which gives it that characteristic stiffness and the frosted, milky appearance. At 15\u201325 microns, you get a standard supermarket T-shirt bag that holds 3\u20135 kg; at 30\u201350 microns, it becomes a bin liner with enough tear resistance for household waste.<\/p>\n\n <p>The reason HDPE dominates is straightforward: at equal thickness, it is roughly 3\u20134 times stronger than LDPE. That means you use less material to achieve the same strength, making it the most cost-effective option for high-volume applications. The trade-off is flexibility \u2014 HDPE bags feel stiff, they crinkle audibly, and they lack the transparent, premium look that retail brands often want.<\/p>\n\n <p><strong>Meilleur pour :<\/strong> grocery bags, bin liners, industrial packaging where cost-per-unit and strength matter more than appearance.<\/p>\n\n \n <h3>LDPE (Low-Density Polyethylene) \u2014 Flexibility and Clarity<\/h3>\n\n <p>If HDPE is the workhorse, LDPE is the showroom model. It is soft, glossy, and highly transparent \u2014 the material behind boutique shopping bags, bread bags, and garment covers from the dry cleaner.<\/p>\n\n <p>The structural difference is in the polymer chains. LDPE’s highly branched molecular structure limits crystallization to 45\u201355%, producing density in the 0.91\u20130.94 g\/cm\u00b3 range. Tensile strength drops to 8\u201315 MPa \u2014 far below HDPE \u2014 but what you lose in strength you gain in flexibility, clarity, and heat-sealability. LDPE has a Vicat softening point of 85\u201395\u00b0C, which means it seals easily at lower temperatures and faster line speeds. It stays flexible down to -60\u00b0C, which is why frozen food packaging almost always involves LDPE or its blends.<\/p>\n\n <p>The practical trade-offs: LDPE costs more per unit of strength than HDPE, and it is sensitive to oils and greases, which can cause environmental stress cracking over time. That bakery bag holds bread beautifully but would fail quickly with oily fried food \u2014 which is why some food applications need a multi-layer structure with a barrier layer.<\/p>\n\n <p><strong>Meilleur pour :<\/strong> retail shopping bags, bread and produce bags, shrink wrap, garment covers, and any application where transparency and tactile quality matter.<\/p>\n\n \n <h3>LLDPE (Linear Low-Density Polyethylene) \u2014 The Strength Upgrade<\/h3>\n\n <p>LLDPE is the material that many buyers do not know they need. It looks and feels similar to LDPE, but at identical thickness, it delivers 2\u20133 times the puncture and tear resistance. The reason is in the molecular architecture: where LDPE has long, chaotic branches, LLDPE has short, uniform branches that produce a more even crystalline structure \u2014 not more crystals, just better-organized ones.<\/p>\n\n <p>Density falls in the same 0.915\u20130.940 g\/cm\u00b3 range as LDPE, but Dart Drop Impact values typically exceed 200 g\/\u00b5m versus 100\u2013150 g\/\u00b5m for LDPE (<a href=\"https:\/\/www.astm.org\/d1709-22.html\" rel=\"nofollow\">ASTM D1709<\/a>). Elmendorf tear strength is significantly higher in both machine and transverse directions. On the processing side, LLDPE requires higher extrusion temperatures (190\u2013260\u00b0C versus 176\u2013232\u00b0C for LDPE) and greater motor torque \u2014 an important consideration if you run your own production line.<\/p>\n\n <p>In practice, most “heavy-duty” garbage bags and industrial liners are LDPE-LLDPE blends rather than pure LDPE. Pure LDPE simply cannot deliver the puncture resistance needed for construction waste or sharp-edged industrial scrap. Freezer bags are another LLDPE stronghold, where cold-temperature impact resistance prevents the bag from shattering when dropped.<\/p>\n\n <p>A variant worth knowing: mLLDPE (metallocene-catalyzed LLDPE) offers a narrower molecular weight distribution, which translates to better heat-seal performance and improved optical clarity \u2014 at a higher raw material cost.<\/p>\n\n <p><strong>Meilleur pour :<\/strong> freezer bags, heavy-duty garbage bags, industrial liners, and any application where puncture resistance or cold-temperature performance is non-negotiable.<\/p>\n\n \n <h3>PP (Polypropylene) \u2014 The Premium Performer<\/h3>\n\n <p>Polypropylene is not what most people picture when they think “plastic bag” \u2014 but it should be. PP bags are crystal-clear, stiff, and heat-resistant to 160\u00b0C, making them the material of choice for high-visibility retail packaging, snack foods, and medical sterilization pouches.<\/p>\n\n <p>PP’s density is the lowest of the group at 0.90\u20130.91 g\/cm\u00b3, and its tensile strength of 30\u201340 MPa rivals HDPE. The defining advantage is thermal: a melting point of 160\u2013165\u00b0C for homopolymer PP means it can survive hot-fill processes and steam sterilization that would destroy any PE bag. BOPP (biaxially oriented polypropylene) takes this further \u2014 stretching the film in two directions creates a material with haze as low as 1\u20132%, rivaling glass in clarity, which is why premium snack and confectionery packaging almost always uses BOPP.<\/p>\n\n <p>The critical limitation: pure homopolymer PP becomes brittle around 0\u00b0C. Drop a frozen food bag made of pure PP, and it may shatter. Copolymer grades address this, pushing the brittle point down to roughly -20\u00b0C, but at added cost. UV stability is another weakness \u2014 PP degrades faster than PE under sunlight unless stabilizers are added.<\/p>\n\n <p><strong>Meilleur pour :<\/strong> premium retail bags, snack and confectionery packaging (BOPP), medical sterilization pouches, woven sacks for bulk grains and fertilizers.<\/p>\n\n \n \n \n <div class=\"bp-2-compare\">\n <div class=\"bp-header\">\n <svg viewbox=\"0 0 24 24\" width=\"24\" height=\"24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);\">\n <path d=\"M12 20V10\"\/>\n <path d=\"M18 20V4\"\/>\n <path d=\"M6 20v-4\"\/>\n <\/svg>\n <span class=\"bp-label\">Polymer Comparison<\/span>\n <\/div>\n <table class=\"bp-table\">\n <thead>\n <tr>\n <th>Propri\u00e9t\u00e9<\/th>\n <th>PEHD<\/th>\n <th>LDPE<\/th>\n <th>LLDPE<\/th>\n <th>PP<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr>\n <td class=\"prop-col\">Densit\u00e9<\/td>\n <td>0.94\u20130.97 g\/cm\u00b3<\/td>\n <td>0.91\u20130.94 g\/cm\u00b3<\/td>\n <td>0.915\u20130.940 g\/cm\u00b3<\/td>\n <td>0.90\u20130.91 g\/cm\u00b3<\/td>\n <\/tr>\n <tr>\n <td class=\"prop-col\">R\u00e9sistance \u00e0 la traction<\/td>\n <td>20\u201330 MPa<\/td>\n <td>8\u201315 MPa<\/td>\n <td>Dart Drop >200 g\/\u00b5m<\/td>\n <td>30\u201340 MPa<\/td>\n <\/tr>\n <tr>\n <td class=\"prop-col\">Melting Point<\/td>\n <td>120\u2013130\u00b0C<\/td>\n <td>85\u201395\u00b0C (Vicat)<\/td>\n <td>190\u2013260\u00b0C (extrusion)<\/td>\n <td>160\u2013165\u00b0C<\/td>\n <\/tr>\n <tr>\n <td class=\"prop-col\">Meilleur pour<\/td>\n <td>Grocery bags, bin liners<\/td>\n <td>Retail, bread bags, garment covers<\/td>\n <td>Freezer bags, heavy-duty liners<\/td>\n <td>Premium retail, BOPP, medical<\/td>\n <\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n \n \n \n <h2>Design and Structure Types \u2014 How Plastic Bags Are Built<\/h2>\n\n <p>Material determines the bag’s feel, but design determines what it can actually do. A bag’s structure governs how it loads, how it carries, how it seals, and how it presents on a shelf. Four dimensions define any bag design: <strong>loading method<\/strong> (open top, side access, expandable volume), <strong>carrying method<\/strong> (handle type or none), <strong>closure method<\/strong> (single-use seal, resealable, or none), and <strong>display method<\/strong> (flat lay, hanging, or standing).<\/p>\n\n \n <h3>Flat Bags, Gusseted Bags, and Poly Tubing \u2014 The Fundamental Forms<\/h3>\n\n <p>Flat poly bags are exactly what they sound like: two sheets of film sealed on three sides, open on the fourth. They are the simplest, cheapest, and fastest to produce \u2014 bottom-seal versions run at 250\u2013500 bags per minute on standard equipment. Side-seal variants suit automated packing lines where the bag is opened, filled, and sealed by machine.<\/p>\n\n <p>Gusseted bags add expandable folds to the sides or bottom, letting the bag hold bulkier, irregularly shaped items without stretching or tearing. A bottom gusset turns a flat bag into something that can stand upright \u2014 the foundational structure behind coffee bean bags, pet food packaging, and e-commerce mailers. Gusset depths typically range from 5 to 20 cm (2\u20138 inches), and the expandable volume gain over a flat bag of the same width can hit 30\u201350%.<\/p>\n\n <p>Poly tubing sits at the simplest end of the spectrum: a continuous roll of film available in widths from 2.5 cm to over 3 meters, which the user cuts and seals to custom lengths. For low-volume or variable-length packaging, it is the cheapest option per unit.<\/p>\n\n \n <h3>T-Shirt Bags, Handle Bags, and Carry-Out Designs \u2014 Built for Convenience<\/h3>\n\n <p>The T-shirt bag \u2014 the classic supermarket singlet \u2014 is the highest-volume plastic bag design in the world. It is an HDPE bag with integrated loop handles die-cut from the bag body, typically 30\u201346 cm wide by 46\u201361 cm long, at 15\u201325 microns. Production speed reaches 120\u2013250 bags per minute on twin-line machines. Cost per unit can drop below one cent at volume.<\/p>\n\n <p>Soft loop handle bags use LDPE for a more flexible, premium feel and are the standard for boutique and department store retail. Die-cut handle bags take the handle-from-body concept further with precisely cut openings that create a sleeker, more branded look \u2014 common in mid-to-high-end retail where the bag is part of the customer experience.<\/p>\n\n <p>Patch handle bags add a separate reinforced handle piece, pushing load capacity to 5\u201310 kg. They suit heavier items \u2014 books, hardware, bulk groceries \u2014 where an integrated T-shirt handle would tear. The cost premium over a T-shirt bag is roughly 2\u20133 times, driven by the extra material and the additional handle-sealing station on the production line.<\/p>\n\n <p>A procurement reality worth noting: T-shirt bag machines and soft-loop handle bag machines are fundamentally different equipment. If you invest in one, you cannot simply switch tooling to produce the other \u2014 a fact that shapes the production strategy of every bag factory.<\/p>\n\n \n <h3>Zipper Bags, Slider Bags, and Resealable Closures \u2014 Repeated Access Design<\/h3>\n\n <p>Resealable bags solve a specific problem: the product inside is consumed over time, not all at once. Press-to-close zippers are the most common and cost-effective design, used for frozen vegetables, shredded cheese, and deli meats. Slider zippers add a plastic slider that glides along the track, making opening and closing easier \u2014 important for products targeting elderly consumers or for bags opened dozens of times, like bulk snacks or pet food.<\/p>\n\n <p>The engineering challenge is the zipper opening force. Too tight, and consumers complain or return the product. Too loose, and the bag leaks \u2014 or worse, loses its oxygen barrier and causes spoilage. The industry sweet spot is 5\u201315 N of opening force. Dual-track zippers can achieve 3 times the air-tightness of single-track designs, which matters for coffee beans, nuts, and other oxygen-sensitive products.<\/p>\n\n <p>On the production side, zipper insertion adds a dedicated station to the bag-making machine, slowing line speed from 250\u2013500 bags per minute (for flat bags) to 100\u2013150 for zipper bags. The zipper material itself \u2014 typically LDPE or PP \u2014 must match the bag body polymer to avoid recycling compatibility issues.<\/p>\n\n <p>For procurement managers, one practical verification step: always request zipper opening force test data from your supplier. This single parameter accounts for a disproportionate share of consumer complaints about resealable packaging.<\/p>\n\n \n <h3>Stand-Up Pouches, Bottom-Gusset Bags, and Specialty Structures \u2014 Shelf-Ready Packaging<\/h3>\n\n <p>The stand-up pouch has transformed retail packaging in the last decade. Walk down any snack aisle, and you will see why: a pouch that stands upright on the shelf, with a large printable front panel, a bottom gusset for stability, and multi-layer construction for barrier performance. It is the most technically sophisticated bag type \u2014 and the most expensive to produce.<\/p>\n\n <p>A typical stand-up pouch for food uses a three-layer laminate: 12-micron PET for outer print surface and stiffness, 7\u20139-micron aluminum foil for the oxygen and moisture barrier, and 50\u201380-micron PE for the inner heat-seal layer. Oxygen transmission rates below 1 cc\/m\u00b2\/day are achievable with the aluminum foil layer \u2014 essential for products like coffee, nuts, and jerky where oxidation means staleness.<\/p>\n\n <p>Flat-bottom box pouches take the concept further with a rectangular base that provides better shelf stability and a more premium look. Spout pouches add a fitted pour spout for liquid products \u2014 think laundry detergent, sports drinks, and baby food purees.<\/p>\n\n <p>The capital reality: a stand-up pouch machine belongs to an entirely different class of equipment from a flat bag machine. Production speeds drop to 40\u201380 pouches per minute, scrap rates run 5\u20138% versus 1\u20132% for simple bags, and the machine itself costs several multiples more. This is why most food startups buy pouches from converters rather than producing them in-house \u2014 the barrier to entry is genuinely high.<\/p>\n\n \n \n \n <div class=\"bp-3-insight\">\n <div class=\"bp-header\">\n <svg viewbox=\"0 0 24 24\" width=\"24\" height=\"24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-accent);\">\n <path d=\"M9 18h6\"\/>\n <path d=\"M10 22h4\"\/>\n <path d=\"M15.09 14c.18-.98.65-1.74 1.41-2.5A4.65 4.65 0 0 0 18 8 6 6 0 0 0 6 8c0 1 .23 2.23 1.5 3.5A4.61 4.61 0 0 1 8.91 14\"\/>\n <\/svg>\n <span class=\"bp-label\">Point cl\u00e9<\/span>\n <\/div>\n <div class=\"bp-body\">\n The stand-up pouch machine belongs to an entirely different class from a flat bag machine \u2014 production speeds of 40\u201380 pouches per minute versus 250\u2013500, scrap rates of 5\u20138% versus 1\u20132%, and a machine cost several times higher. This is why most food startups buy pouches from converters rather than producing in-house.\n <\/div>\n <div class=\"bp-stats\">\n <div class=\"bp-stat-card\">\n <div class=\"stat-number\">40\u201380\/min<\/div>\n <div class=\"stat-label\">Vitesse de production<\/div>\n <\/div>\n <div class=\"bp-stat-card\">\n <div class=\"stat-number\">5\u20138%<\/div>\n <div class=\"stat-label\">Scrap Rate<\/div>\n <\/div>\n <\/div>\n <\/div>\n\n \n \n \n <h2>From Raw Material to Finished Bag \u2014 How Each Type Is Manufactured<\/h2>\n\n <p>Every plastic bag starts the same way \u2014 polymer pellets fed into a hopper \u2014 but diverges dramatically at the forming stage. The machine you choose determines which bag types you can produce, and the quality of that machine determines how competitive your product will be. Understanding this connection turns abstract “types of plastic bags” into concrete production decisions.<\/p>\n\n<img decoding=\"async\" src=\"https:\/\/www.ketegroup.com\/wp-content\/uploads\/2026\/05\/types-of-plastic-bags-for-food-packaging-3.webp\" \n alt=\"types de sacs en plastique pour l'emballage\" \n style=\"width: 512px; height: 384px; max-width: 100%; object-fit: cover; border-radius: 12px; margin: 30px auto; display: block; box-shadow: 10px 10px 60px 0px rgba(210, 221, 224, 0.35); transition: all 0.3s ease; cursor: pointer;\"\n onmouseover=\"this.style.transform='translateY(-5px) scale(1.03)'; this.style.boxShadow='15px 25px 80px 0px rgba(210, 221, 224, 0.45)';\"\n onmouseout=\"this.style.transform='translateY(0) scale(1)'; this.style.boxShadow='10px 10px 60px 0px rgba(210, 221, 224, 0.35)';\">\n\n \n <h3>Film Blowing and Raw Material Preparation \u2014 Where Every Bag Begins<\/h3>\n\n <p>The blown film extrusion process is the universal starting point. Polymer pellets enter a heated barrel where a rotating screw melts and pressurizes them. The molten polymer exits through a circular die, forming a thin tube that is immediately inflated with air \u2014 like blowing up a balloon vertically \u2014 into a bubble 2\u20134 times the die diameter. This blow-up ratio (BUR) is a critical parameter: high BUR strengthens the film in the transverse direction by stretching molecules sideways; low BUR favors machine-direction strength.<\/p>\n\n <p>Cooling air from an external ring solidifies the bubble, which then passes through collapsing frames and nip rollers into a flat lay-flat tube wound onto rolls. Modern lines with internal bubble cooling (IBC) can boost output by 30\u201350% and significantly improve thickness uniformity \u2014 typically paying back the investment within 12 months through higher throughput and lower scrap.<\/p>\n\n <p>The material matters at this stage. HDPE needs slower cooling rates (30\u201380 m\/min line speed) due to its high crystallinity. LDPE runs faster (50\u2013150 m\/min). LLDPE demands higher melt temperatures and more motor torque. Multi-layer coextrusion lines \u2014 running three or more extruders into a single die \u2014 can combine different materials into one film: an outer LDPE layer for printability, a middle LLDPE layer for strength, and an inner EVA layer for low-temperature heat-seal performance. The energy cost runs 40\u201360% higher than a single-layer line, but the film performance gain justifies it for demanding applications.<\/p>\n\n \n \n \n <div class=\"bp-4-process\">\n <div class=\"bp-header\">\n <svg viewbox=\"0 0 24 24\" width=\"24\" height=\"24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);\">\n <circle cx=\"12\" cy=\"12\" r=\"3\"\/>\n <path d=\"M19.4 15a1.65 1.65 0 0 0 .33 1.82l.06.06a2 2 0 0 1 0 2.83 2 2 0 0 1-2.83 0l-.06-.06a1.65 1.65 0 0 0-1.82-.33 1.65 1.65 0 0 0-1 1.51V21a2 2 0 0 1-2 2 2 2 0 0 1-2-2v-.09A1.65 1.65 0 0 0 9 19.4a1.65 1.65 0 0 0-1.82.33l-.06.06a2 2 0 0 1-2.83 0 2 2 0 0 1 0-2.83l.06-.06A1.65 1.65 0 0 0 4.68 15a1.65 1.65 0 0 0-1.51-1H3a2 2 0 0 1-2-2 2 2 0 0 1 2-2h.09A1.65 1.65 0 0 0 4.6 9a1.65 1.65 0 0 0-.33-1.82l-.06-.06a2 2 0 0 1 0-2.83 2 2 0 0 1 2.83 0l.06.06A1.65 1.65 0 0 0 9 4.68a1.65 1.65 0 0 0 1-1.51V3a2 2 0 0 1 2-2 2 2 0 0 1 2 2v.09a1.65 1.65 0 0 0 1 1.51 1.65 1.65 0 0 0 1.82-.33l.06-.06a2 2 0 0 1 2.83 0 2 2 0 0 1 0 2.83l-.06.06A1.65 1.65 0 0 0 19.4 9a1.65 1.65 0 0 0 1.51 1H21a2 2 0 0 1 2 2 2 2 0 0 1-2 2h-.09a1.65 1.65 0 0 0-1.51 1z\"\/>\n <\/svg>\n <span class=\"bp-label\">The Process<\/span>\n <\/div>\n <div class=\"bp-flow\">\n <div class=\"bp-flow-step\">\n <div class=\"step-circle\">1<\/div>\n <div class=\"step-label-wrap\">\n <div class=\"step-label\">Feed<\/div>\n <div class=\"step-sub\">pellets → hopper<\/div>\n <\/div>\n <\/div>\n <div class=\"bp-flow-arrow\">\n <svg viewbox=\"0 0 24 24\" width=\"20\" height=\"20\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\">\n <line x1=\"5\" y1=\"12\" x2=\"19\" y2=\"12\"\/>\n <polyline points=\"12 5 19 12 12 19\"\/>\n <\/svg>\n <\/div>\n <div class=\"bp-flow-step\">\n <div class=\"step-circle\">2<\/div>\n <div class=\"step-label-wrap\">\n <div class=\"step-label\">Melt<\/div>\n <div class=\"step-sub\">screw + heat<\/div>\n <\/div>\n <\/div>\n <div class=\"bp-flow-arrow\">\n <svg viewbox=\"0 0 24 24\" width=\"20\" height=\"20\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\">\n <line x1=\"5\" y1=\"12\" x2=\"19\" y2=\"12\"\/>\n <polyline points=\"12 5 19 12 12 19\"\/>\n <\/svg>\n <\/div>\n <div class=\"bp-flow-step\">\n <div class=\"step-circle\">3<\/div>\n <div class=\"step-label-wrap\">\n <div class=\"step-label\">Blow<\/div>\n <div class=\"step-sub\">die → bubble, BUR 2\u20134:1<\/div>\n <\/div>\n <\/div>\n <div class=\"bp-flow-arrow\">\n <svg viewbox=\"0 0 24 24\" width=\"20\" height=\"20\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\">\n <line x1=\"5\" y1=\"12\" x2=\"19\" y2=\"12\"\/>\n <polyline points=\"12 5 19 12 12 19\"\/>\n <\/svg>\n <\/div>\n <div class=\"bp-flow-step\">\n <div class=\"step-circle\">4<\/div>\n <div class=\"step-label-wrap\">\n <div class=\"step-label\">Wind<\/div>\n <div class=\"step-sub\">collapse → roll<\/div>\n <\/div>\n <\/div>\n <\/div>\n <div class=\"bp-caption\">IBC-equipped lines boost output 30\u201350% and typically pay back within 12 months.<\/div>\n <\/div>\n\n \n <h3>Bag Forming Processes by Type \u2014 How Different Machines Shape Different Bags<\/h3>\n\n <p>This is where the paths diverge, and where the connection between bag type and production equipment becomes concrete.<\/p>\n\n <p>UN <strong>T-shirt bag machine<\/strong> takes the printed or unprinted roll stock through a sequence of stations: unwinding → bottom sealing → handle die-cutting → individual bag cutting → stacking and counting. Production speed runs 120\u2013250 bags per minute on twin-line configurations. The die-cutting station is the critical differentiator \u2014 it creates the integrated handles that define the T-shirt format.<\/p>\n\n <p>UN <strong>flat bag \/ bottom-seal machine<\/strong> is simpler and faster: unwind → bottom seal bar → cut-off knife → stack. With no handle station to slow things down, speeds reach 250\u2013500 bags per minute. Side-seal variants seal along the edges instead of the bottom, producing bags better suited to automated filling lines.<\/p>\n\n <p>UN <strong>zipper bag machine<\/strong> adds a zipper insertion and heat-sealing station between unwinding and bag forming. This station feeds pre-formed zipper profile (LDPE or PP, matched to bag body material) into position between the film layers, where heated bars bond it in place. The added complexity drops line speed to 100\u2013150 bags per minute and increases scrap rates to 3\u20135%.<\/p>\n\n <p>UN <strong>stand-up pouch machine<\/strong> is the most complex of the group. It handles multiple roll stocks simultaneously (outer print layer, barrier layer, inner seal layer), forms the bottom gusset, executes multi-side sealing, and often integrates a zipper station as well. Speeds drop to 40\u201380 pouches per minute. Scrap rates of 5\u20138% are normal and reflect the complexity of coordinating multiple material webs and seal stations.<\/p>\n\n <p>The servo-versus-mechanical distinction matters across all machine types. Servo-driven machines use programmable motors for each motion axis, achieving positioning accuracy of \u00b10.1 mm and enabling quick changeovers between bag sizes via touchscreen recipe selection. Mechanical cam-driven machines are cheaper to buy but deliver \u00b11.5 mm accuracy and require physical cam changes to switch bag dimensions \u2014 a process that can take hours. For factories that change bag sizes frequently, servo is usually the better long-term investment despite the higher upfront cost.<\/p>\n\n <p>For anyone entering bag production, the equipment decision chain is straightforward: first, determine your target bag type (selling to supermarkets means T-shirt bags; selling to food brands means zipper or stand-up pouches); second, match your budget and volume expectations to machine class; third, consider whether servo flexibility justifies the premium. Equipment manufacturers who specialize in multi-type bag making lines \u2014 such as KETE GROUP, whose product range spans T-shirt bag machines, flat bag machines, and zipper bag systems \u2014 can provide the technical guidance to navigate this decision, but the strategic choice of which bag types to produce should always come first.<\/p>\n\n \n \n \n <div class=\"bp-5-cta\">\n <div class=\"cta-icon\">\n <svg viewbox=\"0 0 24 24\" width=\"32\" height=\"32\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:#FFFFFF;opacity:0.9;\">\n <circle cx=\"12\" cy=\"12\" r=\"10\"\/>\n <path d=\"M9.09 9a3 3 0 0 1 5.83 1c0 2-3 3-3 3\"\/>\n <line x1=\"12\" y1=\"17\" x2=\"12.01\" y2=\"17\"\/>\n <\/svg>\n <\/div>\n <div class=\"cta-title\">Not Sure Which Equipment Fits Your Target Bag Type?<\/div>\n <div class=\"cta-subtitle\">Get technical guidance matched to your production goals \u2014 from a single machine to a complete line.<\/div>\n <a class=\"cta-btn\" href=\"https:\/\/www.ketegroup.com\/fr\/contact\/\">Request Equipment Guidance<\/a>\n <\/div>\n\n \n <h3>Quality Control and Thickness Standards \u2014 What Separates Good Bags from Bad<\/h3>\n\n <p>For B2B buyers, quality control is the conversation that happens after the price negotiation \u2014 but before the purchase order. A bag that fails in the field costs far more than the cents saved on a cheaper supplier.<\/p>\n\n <p>Thickness tolerance is the most basic metric. \u00b110% of nominal thickness is the industry baseline; \u00b15% indicates a supplier with tight process control. Thickness variation beyond 15% causes downstream problems: inconsistent print registration, unreliable seal strength, and bags that fail unpredictably under load.<\/p>\n\n <p>Key laboratory tests include tensile strength (<a href=\"https:\/\/www.astm.org\/d0882-18.html\" rel=\"nofollow\">ASTM D882<\/a> \u2014 25.4 mm wide specimen, 50 mm gauge length, 500 mm\/min test speed), Dart Drop Impact (<a href=\"https:\/\/www.astm.org\/d1709-22.html\" rel=\"nofollow\">ASTM D1709<\/a> \u2014 measuring the energy required to cause failure under specified conditions), and heat seal strength (<a href=\"https:\/\/www.astm.org\/f0088-21.html\" rel=\"nofollow\">ASTM F88<\/a> \u2014 minimum 15 N per 25 mm width for food-grade packaging). The coefficient of friction (COF, <a href=\"https:\/\/www.astm.org\/d1894-14.html\" rel=\"nofollow\">ASTM D1894<\/a>) should fall between 0.2 and 0.4 for bags running on automated packing lines \u2014 too slippery and they slide off conveyors; too tacky and they jam.<\/p>\n\n <p>Each bag type has its characteristic defects. T-shirt bags suffer from asymmetric handles when die-cutting alignment drifts. Zipper bags fail when the zipper profile delaminates from the film \u2014 a bonding problem traceable to insufficient sealing temperature or pressure. Stand-up pouches leak at the bottom gusset corner seals, where three or four material layers must fuse perfectly in a single sealing cycle. A practical incoming inspection checklist \u2014 random sample of 10 bags, measure thickness at 3 points each, load-test the handles, peel-test the seals, and rub-test any printing \u2014 catches most problems before they reach the customer.<\/p>\n\n \n \n \n <div class=\"bp-6-checklist\">\n <div class=\"bp-accent-bar\"><\/div>\n <div class=\"bp-content\">\n <div class=\"bp-header\">\n <svg viewbox=\"0 0 24 24\" width=\"20\" height=\"20\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);\">\n <path d=\"M16 4h2a2 2 0 0 1 2 2v14a2 2 0 0 1-2 2H6a2 2 0 0 1-2-2V6a2 2 0 0 1 2-2h2\"\/>\n <rect x=\"8\" y=\"2\" width=\"8\" height=\"4\" rx=\"1\" ry=\"1\"\/>\n <path d=\"M9 14l2 2 4-4\"\/>\n <\/svg>\n <span class=\"bp-label\">Quick Inspection Checklist<\/span>\n <\/div>\n <div class=\"bp-item\">\n <svg viewbox=\"0 0 24 24\" width=\"16\" height=\"16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);flex-shrink:0;\">\n <path d=\"M22 11.08V12a10 10 0 1 1-5.93-9.14\"\/>\n <polyline points=\"22 4 12 14.01 9 11.01\"\/>\n <\/svg>\n <span>Measure thickness at 3 points on 10 random bags<\/span>\n <\/div>\n <div class=\"bp-item\">\n <svg viewbox=\"0 0 24 24\" width=\"16\" height=\"16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);flex-shrink:0;\">\n <path d=\"M22 11.08V12a10 10 0 1 1-5.93-9.14\"\/>\n <polyline points=\"22 4 12 14.01 9 11.01\"\/>\n <\/svg>\n <span>Load-test handles with rated weight for 30 seconds<\/span>\n <\/div>\n <div class=\"bp-item\">\n <svg viewbox=\"0 0 24 24\" width=\"16\" height=\"16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);flex-shrink:0;\">\n <path d=\"M22 11.08V12a10 10 0 1 1-5.93-9.14\"\/>\n <polyline points=\"22 4 12 14.01 9 11.01\"\/>\n <\/svg>\n <span>Peel-test heat seals \u2014 failure at seal line = over-sealing<\/span>\n <\/div>\n <div class=\"bp-item\">\n <svg viewbox=\"0 0 24 24\" width=\"16\" height=\"16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);flex-shrink:0;\">\n <path d=\"M22 11.08V12a10 10 0 1 1-5.93-9.14\"\/>\n <polyline points=\"22 4 12 14.01 9 11.01\"\/>\n <\/svg>\n <span>Rub-test printed surface with dry cloth (10 passes)<\/span>\n <\/div>\n <div class=\"bp-item\">\n <svg viewbox=\"0 0 24 24\" width=\"16\" height=\"16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-primary);flex-shrink:0;\">\n <path d=\"M22 11.08V12a10 10 0 1 1-5.93-9.14\"\/>\n <polyline points=\"22 4 12 14.01 9 11.01\"\/>\n <\/svg>\n <span>Check zipper opening force (target: 5\u201315 N)<\/span>\n <\/div>\n <\/div>\n <\/div>\n\n \n \n \n <h2>Choosing the Right Plastic Bag \u2014 Application Matching Guide<\/h2>\n\n <p>The previous sections gave you the full technical picture. This section reorganizes that information around your actual use case. Find your application in the left column; the rest of the row tells you what to buy.<\/p>\n\n <div class=\"table-wrapper\">\n <table>\n <thead>\n <tr>\n <th>Application<\/th>\n <th>Recommended Material<\/th>\n <th>Recommended Bag Type<\/th>\n <th>Typical Thickness<\/th>\n <th>Principales consid\u00e9rations<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr>\n <td>Supermarket \/ retail checkout<\/td>\n <td>PEHD<\/td>\n <td>Sac \u00e0 t-shirt<\/td>\n <td>15\u201325 \u00b5m<\/td>\n <td>Lowest cost per unit; holds 3\u20135 kg; check local single-use plastic regulations<\/td>\n <\/tr>\n <tr>\n <td>Boutique \/ fashion retail<\/td>\n <td>LDPE<\/td>\n <td>Die-Cut Handle or Soft Loop<\/td>\n <td>40\u201360 \u00b5m<\/td>\n <td>Brand feel and transparency matter; printing quality is a purchase driver<\/td>\n <\/tr>\n <tr>\n <td>Bread, pastries, bakery<\/td>\n <td>LDPE<\/td>\n <td>Flat \/ Bottom-Seal<\/td>\n <td>25\u201335 \u00b5m<\/td>\n <td>Food safety certification required; transparency for product visibility<\/td>\n <\/tr>\n <tr>\n <td>Frozen foods (vegetables, meat, seafood)<\/td>\n <td>LLDPE + LDPE blend<\/td>\n <td>Flat \/ Zipper Bag<\/td>\n <td>50\u201375 \u00b5m<\/td>\n <td>Cold-temperature impact resistance critical; puncture resistance for bone-in products<\/td>\n <\/tr>\n <tr>\n <td>Snacks, confectionery, coffee (shelf display)<\/td>\n <td>BOPP or PET\/PE laminate<\/td>\n <td>Sachet \u00e0 fond plat<\/td>\n <td>60\u2013100 \u00b5m (multi-layer)<\/td>\n <td>Oxygen barrier essential for shelf life; print quality drives purchase decisions<\/td>\n <\/tr>\n <tr>\n <td>Industrial parts, hardware, heavy goods<\/td>\n <td>HDPE or LLDPE<\/td>\n <td>Flat \/ Gusseted<\/td>\n <td>75\u2013150 \u00b5m<\/td>\n <td>Puncture and tear resistance; load capacity 10\u201325 kg<\/td>\n <\/tr>\n <tr>\n <td>Medical device \/ sterilization<\/td>\n <td>PP or HDPE<\/td>\n <td>Flat \/ Self-Seal<\/td>\n <td>50\u2013100 \u00b5m<\/td>\n <td>Sterilization method compatibility (EtO, gamma, steam); no fiber shedding<\/td>\n <\/tr>\n <tr>\n <td>Waste disposal (household)<\/td>\n <td>LDPE + LLDPE blend<\/td>\n <td>T-Shirt \/ Drawstring<\/td>\n <td>30\u201350 \u00b5m<\/td>\n <td>Tear resistance for irregular waste; drawstring convenience for kitchen use<\/td>\n <\/tr>\n <tr>\n <td>Waste disposal (industrial \/ construction)<\/td>\n <td>LDPE + LLDPE blend<\/td>\n <td>Flat \/ Gusseted<\/td>\n <td>80\u2013150 \u00b5m<\/td>\n <td>Heavy puncture resistance; consider recycled content (PCR) for sustainability mandates<\/td>\n <\/tr>\n <tr>\n <td>E-commerce shipping<\/td>\n <td>LDPE or LLDPE<\/td>\n <td>Poly Mailer \/ Flat<\/td>\n <td>50\u201380 \u00b5m<\/td>\n <td>Opaque for privacy; self-seal adhesive strip; tamper-evident optional<\/td>\n <\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p><strong>How to use this table:<\/strong> Start with your product \u2014 what are you packing, how heavy is it, what shape? Then check display requirements \u2014 does the customer need to see the product? Finally, confirm regulatory and budget constraints. Common mistakes to avoid: choosing by price alone (a cheaper thinner bag that tears means higher total cost from returns and damage), ignoring filling-line compatibility (wrong COF = jammed automation), and overlooking destination-market regulations (the EU’s EN 13432 composting standard has no equivalent in many markets where “biodegradable” claims remain unregulated).<\/p>\n\n \n \n \n <h2>Sustainable and Eco-Friendly Plastic Bag Alternatives \u2014 What Actually Works<\/h2>\n\n <p>Sustainability in plastic bags is a landscape of genuine innovation, marketing hype, and well-intentioned solutions that fail in the real world. Here is an honest assessment of what is available, what the certifications actually mean, and where the trade-offs lie.<\/p>\n\n <div class=\"table-wrapper\">\n <table>\n <thead>\n <tr>\n <th>Solution<\/th>\n <th>Material Base<\/th>\n <th>Degradation Conditions<\/th>\n <th>Degradation Time<\/th>\n <th>Certification<\/th>\n <th>Limitation principale<\/th>\n <th>Cost vs. Conventional PE<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr>\n <td>PLA (Polylactic Acid)<\/td>\n <td>Corn starch \/ sugarcane<\/td>\n <td>Industrial compost (58\u00b0C, high humidity)<\/td>\n <td>3 \u00e0 6 mois<\/td>\n <td>EN 13432, ASTM D6400<\/td>\n <td>Glass transition at 55\u201360\u00b0C \u2014 cannot handle hot fill; brittle; contaminates PE recycling streams<\/td>\n <td>3 \u00e0 5 fois\u00d7<\/td>\n <\/tr>\n <tr>\n <td>PBAT + PLA blend<\/td>\n <td>Fossil-based biodegradable polyester + PLA<\/td>\n <td>Industrial compost<\/td>\n <td>3 \u00e0 6 mois<\/td>\n <td>EN 13432<\/td>\n <td>More flexible than pure PLA; still requires industrial composting infrastructure<\/td>\n <td>2\u20134\u00d7<\/td>\n <\/tr>\n <tr>\n <td>Oxo-degradable (EPI additive)<\/td>\n <td>Conventional PE + metal-salt additive<\/td>\n <td>Light\/heat triggers fragmentation<\/td>\n <td>18\u201360 months to fragment<\/td>\n <td>No recognized international standard<\/td>\n <td>Fragments into microplastics \u2014 does not biodegrade; banned in EU Single-Use Plastics Directive<\/td>\n <td>1.2\u20131.5\u00d7<\/td>\n <\/tr>\n <tr>\n <td>Recycl\u00e9 apr\u00e8s consommation (PCR)<\/td>\n <td>Recycled HDPE\/LDPE re-pelletized<\/td>\n <td>N\/A (circular economy, not degradation)<\/td>\n <td>N\/A<\/td>\n <td>GRS (Global Recycled Standard)<\/td>\n <td>Grayish color, potential odor, 10\u201320% mechanical property loss; food-contact restrictions vary by jurisdiction<\/td>\n <td>1.2\u20131.8\u00d7<\/td>\n <\/tr>\n <tr>\n <td>Paper bags<\/td>\n <td>Kraft paper<\/td>\n <td>Natural degradation<\/td>\n <td>1\u20132 months<\/td>\n <td>FSC (forestry sourcing)<\/td>\n <td>No water resistance; far lower load capacity than PE; production uses 4\u00d7 the energy and 2\u00d7 the water of PE bags<\/td>\n <td>2\u20133\u00d7<\/td>\n <\/tr>\n <tr>\n <td>Downgauging (lightweighting)<\/td>\n <td>Conventional PE, thinner<\/td>\n <td>N\/A<\/td>\n <td>N\/A<\/td>\n <td>No special certification needed<\/td>\n <td>Physical performance limits constrain thinning; currently the most pragmatic “sustainable” path for industrial users<\/td>\n <td>0.8\u20130.9\u00d7<\/td>\n <\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p><strong>EN 13432<\/strong> \u2014 the European standard for industrially compostable packaging \u2014 requires four things: \u226590% biodegradation within 6 months at 58\u00b0C (<a href=\"https:\/\/www.iso.org\/standard\/78712.html\" rel=\"nofollow\">EN ISO 14855-1<\/a>), disintegration to \u226410% fragments larger than 2 mm within 12 weeks, no negative effect on the composting process, and no ecotoxicity in the final compost (verified by plant growth tests per OECD 208).<\/p>\n\n <p>The uncomfortable truth: industrial composting conditions \u2014 58\u00b0C, 50\u201360% humidity, continuous aeration \u2014 are not backyard compost bin conditions. If a PLA bag is sold into a market without industrial composting infrastructure, it will persist in the environment for years, functionally identical to a conventional plastic bag from a litter perspective. Before switching to any “biodegradable” option, verify that your end market actually has the collection and processing infrastructure to handle it.<\/p>\n\n <p>For most industrial and B2B applications today, <strong>downgauging<\/strong> \u2014 using less material to achieve the same performance through better resin grades and process control \u2014 is the most cost-effective and genuinely impactful sustainability move. It reduces material consumption, lowers transport weight, and cuts carbon footprint without requiring new recycling or composting infrastructure that may not exist.<\/p>\n\n \n \n \n <h2>Putting It All Together<\/h2>\n\n <p>You do not need to memorize every polymer density or machine speed to make a good plastic bag decision. What you do need is a clear mental model: material sets the floor for performance and cost, design determines what the bag can actually do, and the manufacturing process decides whether you can make it yourself or need to buy from a converter.<\/p>\n\n <p>If you take away one thing from this guide, let it be this: the question is never just “which type of plastic bag?” It is “which material, in which structure, made on which equipment, for which market?” Each answer narrows the field. A frozen food brand needs LLDPE \u2014 not because it is the cheapest, but because cold-temperature impact resistance is non-negotiable when a bag of frozen chicken hits a warehouse floor. A coffee roaster choosing between a flat bag and a stand-up pouch is really choosing between looking like a commodity and looking like a brand. A factory owner deciding between a T-shirt bag machine and a zipper bag machine is betting on which customers they want to serve for the next ten years.<\/p>\n\n <p>The plastic bag is a simple product. Getting it right is not. That is why understanding the full picture \u2014 materials, design, manufacturing \u2014 pays for itself in better decisions.<\/p>\n\n \n \n \n <div class=\"bp-7-cta\">\n <svg viewbox=\"0 0 24 24\" width=\"32\" height=\"32\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" style=\"color:var(--color-footer-text);\">\n <path d=\"M16.5 9.4 7.55 4.24a1 1 0 0 0-1.1 0L2 7.08\"\/>\n <path d=\"M21 16V8a2 2 0 0 0-1-1.73l-7-4a2 2 0 0 0-2 0l-7 4A2 2 0 0 0 3 8v8a2 2 0 0 0 1 1.73l7 4a2 2 0 0 0 2 0l7-4A2 2 0 0 0 21 16z\"\/>\n <polyline points=\"3.29 7 12 12 20.71 7\"\/>\n <line x1=\"12\" y1=\"22\" x2=\"12\" y2=\"12\"\/>\n <\/svg>\n <div class=\"cta-title\">Ready to Build Your Bag Production Line?<\/div>\n <div class=\"cta-subtitle\">KETE GROUP provides bag making machines for T-shirt bags, flat bags, zipper bags, and more \u2014 with technical support from consultation to after-sales.<\/div>\n <div class=\"cta-chips\">\n <span class=\"cta-chip\">Multi-Type Machines<\/span>\n <span class=\"cta-chip\">Custom Configurations<\/span>\n <span class=\"cta-chip\">Global Support<\/span>\n <\/div>\n <a class=\"cta-btn\" href=\"https:\/\/www.ketegroup.com\/fr\/contact\/\">Parler \u00e0 un ing\u00e9nieur<\/a>\n <\/div>\n\n \n \n \n <hr>\n\n <p style=\"font-size:14px;color:var(--color-text-secondary);margin-bottom:8px;font-weight:600;\">R\u00e9f\u00e9rences<\/p>\n <ul style=\"font-size:13px;color:var(--color-text-secondary);padding-left:1.2em;list-style:disc outside;\">\n <li>ASTM International. “ASTM D4976-12a(2020) \u2014 Standard Specification for Polyethylene Plastics Molding and Extrusion Materials.” 2020. <a href=\"https:\/\/www.astm.org\/d4976-12ar20.html\" rel=\"nofollow\">https:\/\/www.astm.org\/d4976-12ar20.html<\/a><\/li>\n <li>British Plastics Federation. “Standards for Compostability \u2014 EN 13432.” <a href=\"https:\/\/www.bpf.co.uk\/Topics\/Standards_for_compostability.aspx\" rel=\"nofollow\">https:\/\/www.bpf.co.uk\/Topics\/Standards_for_compostability.aspx<\/a><\/li>\n <li>ASTM International. “ASTM D882-18 \u2014 Standard Test Method for Tensile Properties of Thin Plastic Sheeting.” <a href=\"https:\/\/www.astm.org\/d0882-18.html\" rel=\"nofollow\">https:\/\/www.astm.org\/d0882-18.html<\/a><\/li>\n <li>ASTM International. “ASTM D1709-22 \u2014 Standard Test Methods for Impact Resistance of Plastic Film by the Free-Falling Dart Method.” <a href=\"https:\/\/www.astm.org\/d1709-22.html\" rel=\"nofollow\">https:\/\/www.astm.org\/d1709-22.html<\/a><\/li>\n <li>ASTM International. “ASTM F88-21 \u2014 Standard Test Method for Seal Strength of Flexible Barrier Materials.” <a href=\"https:\/\/www.astm.org\/f0088-21.html\" rel=\"nofollow\">https:\/\/www.astm.org\/f0088-21.html<\/a><\/li>\n <li>ASTM International. “ASTM D1894-14 \u2014 Standard Test Method for Static and Kinetic Coefficients of Friction of Plastic Film and Sheeting.” <a href=\"https:\/\/www.astm.org\/d1894-14.html\" rel=\"nofollow\">https:\/\/www.astm.org\/d1894-14.html<\/a><\/li>\n <li>ISO. “ISO 14855-1:2012 \u2014 Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions.” <a href=\"https:\/\/www.iso.org\/standard\/78712.html\" rel=\"nofollow\">https:\/\/www.iso.org\/standard\/78712.html<\/a><\/li>\n <li>KETE GROUP LIMITED. Company website. <a href=\"https:\/\/www.ketegroup.com\/fr\">https:\/\/www.ketegroup.com\/<\/a><\/li>\n <li>KETE GROUP LIMITED. Contact page. <a href=\"https:\/\/www.ketegroup.com\/fr\/contact\/\">https:\/\/www.ketegroup.com\/contact\/<\/a><\/li>\n <\/ul>\n\n<\/article>\n\n\n<script type=\"application\/ld+json\">{\n \"@context\": \"https:\\\/\\\/schema.org\",\n \"@type\": \"Article\",\n \"headline\": \"Types of Plastic Bags: How Materials, Design, and Manufacturing Shape Your Options\",\n \"description\": \"A comprehensive guide to plastic bag types covering materials (HDPE, LDPE, LLDPE, PP), structural designs, manufacturing processes, and application matching for B2B buyers and packaging professionals.\",\n \"author\": {\n \"@type\": \"Organization\",\n \"name\": \"KETE GROUP\"\n },\n \"about\": {\n \"@type\": \"Thing\",\n \"name\": \"plastic bag manufacturing\",\n \"description\": \"Types of plastic bags, polymer properties, bag design and structures, and manufacturing equipment\"\n }\n}<\/script>\n\n<\/div>\n<\/body>\n<\/html>","protected":false},"excerpt":{"rendered":"<p>Types of Plastic Bags: How Materials, Design, and Manufacturing Shape Your Options Walk into any supermarket, and you will handle at least three different types of plastic bags before you reach the checkout \u2014 the transparent produce bag, the crinkly shopping bag at the register, and maybe a resealable freezer bag waiting at home. They […]<\/p>","protected":false},"author":1,"featured_media":14838,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"28","_seopress_titles_title":"Types of Plastic Bags: Materials, Uses & Machine Options","_seopress_titles_desc":"Discover the exact types of plastic bags your business needs. Compare materials, uses, and bag making machine options to scale your production today.","_seopress_robots_index":"","footnotes":""},"categories":[28],"tags":[],"class_list":["post-14825","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-plastic-bag-making-machines"],"_links":{"self":[{"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/posts\/14825","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/comments?post=14825"}],"version-history":[{"count":4,"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/posts\/14825\/revisions"}],"predecessor-version":[{"id":29735,"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/posts\/14825\/revisions\/29735"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/media\/14838"}],"wp:attachment":[{"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/media?parent=14825"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/categories?post=14825"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ketegroup.com\/fr\/wp-json\/wp\/v2\/tags?post=14825"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}