Follow these key factors step by step to pick the most suitable kraft paper laminated bag, fit for product type, weight, storage, transportation, and budget.
Confirm Your Product Characteristics
- Product form
• Powder: Flour, cement, fertilizer, chemical powder → choose inner PE laminated leak-proof type, fine stitching/sealed bottom to prevent dust leakage.
• Granule: Rice, grain, plastic particles, feed → regular laminated kraft bag with good breathability and tear resistance.
• Solid/irregular goods: Hardware, building materials, spare parts → thick kraft layer + strong lamination for puncture resistance.
• Moisture-sensitive goods: Tea, coffee, snacks, chemical raw materials → full waterproof PE lamination to block moisture and humidity.
- Net weight of goods
• Light (1–5kg): 2–3 layers light kraft paper + thin PE lamination
• Medium (5–25kg): 3–4 layers kraft paper + medium PE lamination
• Heavy (25–50kg): 4–5 layers high-strength kraft paper + thick lamination, reinforced bottom/edge
Choose Lamination Type (Core Selection)
1. PE laminated (Polyethylene): Most common
◦ Advantage: Waterproof, moisture-proof, oil-proof, dust-proof, low cost
◦ Suitable: Food, fertilizer, chemical, grain, cement
2. PP laminated: Higher tensile strength, more wear-resistant
◦ Suitable: Heavy industrial materials, long-distance transportation, repeated handling
3. Aluminum foil laminated: High barrier
◦ Suitable: Food requiring oxygen insulation, fragrance retention, and high-grade chemical raw materials
Bag Structure & Sealing Type
- Bottom type:
◦ Square bottom/block bottom: stand up well, easy stacking, supermarket display
◦ Flat bottom / folded bottom: low cost, good for bulk pallet stacking
• Sealing way:
◦ Sewn top: easy to open & re-seal, for feed/grain
◦ Heat-sealed top: fully airtight, waterproof, for food/powder
• With/without valve:
◦ Valve bag: For cement, dry mortar, powder, automatic filling, no dust overflow
Select Kraft Paper Material & Grammage
- Virgin Kraft paper: Higher strength, tougher, better printing, food-grade safe - for food, premium packaging
- Recycled kraft paper: Lower cost, slightly lower strength - for industrial, fertilizer, and construction materials
- Grammage (g/m²): Higher grammage = thicker & stronger. Match weight load: heavier goods need higher paper grammage.
Environmental & Safety Grade
• Food-grade: Use food-safe kraft paper + food-grade PE lamination, no peculiar smell - for flour, rice, snacks, pet food
• Industrial grade: Ordinary recycled kraft lamination - for chemical, construction, fertilizer (not for direct food contact)
• Eco-friendly: Choose degradable laminated material if you need compostable & plastic-free requirements
Transportation & Storage Conditions
• Long-distance shipping / multiple handling: Choose thick layers, PP lamination, reinforced edge
• Humid warehouse/seaside area: Must choose full waterproof lamination
• Stacking high in warehouse: High burst strength, rigid square bottom bag
Furthermore, if you need brand logo, barcode, ingredient info, or warning marks: Confirm the bag supports flexo printing/gravure printing. And if you want a custom size, for example, if you want to match your filling machine mouth size and pallet standard size, please confirm it carefully.
