Mailing bags (also called express bags, postal bags, and parcel bags) can be divided into many types according to different aspects such as material, structure, and purpose. The following are the classifications and characteristics of common mailing bag types:
1. Classification by material
1.1 PE express bag (polyethylene):
Features: soft, light, waterproof, low price
Commonly used in e-commerce, clothing, and small commodity mailing
Co-extrusion film express bag (CO-EX Film)
Features: multi-layer composite, black inside and white/gray/blue outside, anti-light transmission, high strength
Suitable for scenes that focus on privacy and sealing
1.2 Degradable express bag:
Material: PLA, PBAT, corn starch base, etc.
Features: environmentally friendly, compostable, biodegradable, suitable for sustainable brands
1.3 Paper mailing bag:
Features: recyclable, printable, environmentally friendly
Suitable for light, flat goods (such as stationery, books)
Aluminum foil/composite express bag
Material: PET/AL/PE and other multi-layer composite films
Features: anti-oxidation, moisture-proof, anti-corrosion, suitable for food and cosmetics
2. Classification by sealing method
2.1 Self-sealing type (sealed with adhesive):
Sealed with adhesive strips, one-time use, destroyed when torn
Good tamper-proof performance, commonly found in daily express bags
2.2 Heat-sealed type:
Needs heat sealer to seal, more airtight
Mostly used in industrial packaging bags for logistics packaging
3. Classification by structure and use
3.1 Ordinary flat express bags:
No bottom and no side structure, low cost, suitable for clothing and light items
3.2 With bottom bag/side bag
With bottom or side extension design to increase capacity
Suitable for slightly thicker or irregularly sized goods
3.3 Express bag with bubble pad (bubble bag)
The inner layer contains bubble film, which has a cushioning and shockproof effect
Commonly used for electronic products, cosmetics, and accessories
3.4 Thickened waterproof bag
Used for export and international transportation, strong waterproofness and tear resistance
Commonly used in cross-border e-commerce
3.5 Document mailing bag (document bag)
Common A4 size, with seal, transparent window
Used for mailing contracts, documents, bills, etc.
