BOPP general heat sealing film
1. BOPP general heat sealing film can be divided into double-side heat seal film and single-side heat seal film according to its heat sealing layer characteristic.
（1）double-side heat sealing film. This type of film is ABC structure, side A、side C are heat sealing layers, and mainly used as the packing materials of candy, food, textile, audio and video products, CD-R, etc.
（2） Single-side heat sealing film. This type of film is ABB structure (side A is heat sealing layer, side B will be laminated with PE、BOPP and AL after printing), often used as high-grade packing materials of food, drinks, tea leaves.
2.BOPP general heat sealing film, according to different processing methods, can be divided into Coextruded heat sealing film and heat seal bidirectional stretch film which is made of bidirectional tensile polypropylene film and coated with hot sealing material such as chlorinated polypropylene.
GB/T 12026 - 2000 is the standard of heat sealing bidirectional tensile polypropylene film in China. Its physical and mechanical properties are shown as below table 2-4:
Table 2-4: heat sealing BOPP physical and mechanical properties:
item | index | |||
Class B | ||||
Common Type | Hot shrinkage type | |||
Tensile strength （MPa） | vertical | ≥125 | ≥140 | ≥120 |
horizontal | ≥220 | ≥220 | ≥180 | |
Elongation at break（%） | vertical | ≤200 | ≤180 | ≤220 |
horizontal | ≤80 | ≤70 | ≤80 | |
Hot shrinkage（%） | vertical | ≤5 | ≥6 | ≤5 |
horizontal | ≤5 | ≥6 | ≤4 | |
Haze（%） | ≤4.0 | ≤3.5 | ≤4.0 | |
Friction Coefficient | ≤0.28 | ≤0.28 | ≤0.80 | |
tensile modules of elasticity（MPa） | vertical | ≥2000 | ≥2000 | ≥1800 |
Wetting Tension（mN/m） | - | - | ≥38 | |
Heatsealable strength（N/15mm） | ≥2.0 | ≥2.0 | ≥2.5 | |
Gloss（%） | ≥80.0 | ≥80.0 | ≥80.0 | |
Water vapor permeability 【g/(m²·24h·0.1mm)】 | ≤2.0 | ≤2.0 | ≤2.0 | |
