China Suppliers Factory Heat-Shrinkable Bags for Industrial Packaging Solutions
What is a hot compressed bag?
Heat shrinkable bags, also known as shrink bags or PVC / POF shrink bags, is a packaging material made of special plastic film. When heated (usually using a hot windmill, syringe, or oven), it contracts evenly in one or both directions, thus tightening the contents of the interior to form a strong, transparent, and aesthetically pleasing protective film.
Working principle
The raw materials of the hot compressed bags have gone through a process of "prestretching" and "cooling and forming" before they leave the factory. This means that the plastic molecules are forcefully stretched and arranged when manufactured, and are cooled to secure in a stretched state. When you heat it again, these "frozen" molecular chains return to their original state of relaxation, causing the film to contract in size and tightly adhere to the product surface.
Main types and materials
Features: The most mainstream and environmentally friendly option at present.
- High transparency: excellent presentation.
- High toughness: Good tensile resistance and not easy to break.
- Eco-friendly and non-toxic: Carbon dioxide and water are produced after combustion and meet food packaging standards.
- High shrinkage rate: shrinkage is uniform, surface smooth and aesthetically pleasing.
Disadvantages: The cost is slightly higher than PVC.
Applications: Widely used in food, pharmaceuticals, cosmetics, stationery, toys, electronics, etc.
Features: Early commonly used materials, now gradually replaced by POF.
- Low cost: the price is relatively cheap.
- Strong contractile force: it binds the product tightly.
- Poor environmental performance: When burned, toxic gases such as hydrogen chloride are produced, which is not conducive to the environment and health.
- Easy to turn yellow: After being stored for a long time or being heated, it may turn yellow, affecting aesthetics.
- Poor resilience: relatively easier to tear.
Application: It is still used for some industrial products, card cards, etc. packaging that do not have high environmental requirements.
Features: High performance engineering plastics.
- Extremely strong: very strong and shock resistant.
- High transparency: The presentation was excellent.
- Eco-friendly and recyclable.
Cons: Costs are highest and require higher temperatures to contract.
Application: mainly used in high-end electronics, batteries, cosmetics, tools and other areas that require high-strength protection.
Characteristics: A hard, brittle material.
- Very high transparency, good gloss, and environmentally friendly.
Disadvantage: The texture is fragile and easily cracked.
Applications: Mainly used in food (such as pastries, fruit trays), stationery, toys, etc.
The application of heat-shrinkable bags is extremely widespread, encompassing almost all industries that require packaging:
How to use heat-shrinkable bags?
