When purchasing heat shrink bags, the following factors require attention:

1. Material Selection: What type of heat shrink film or bag do you need? Common materials include POF, PE, and PVC.

2. Material Density & Cost:

   
   
   
   • POF: Density of 0.92, minimum thickness of 0.012mm, and lower actual unit cost.
   • PE: Density of 0.92, minimum thickness of 0.03mm or above, and higher actual unit cost.
   • PVC: Density of 1.4, minimum thickness of 0.02mm, and higher actual unit cost.

3. Physical Properties:

   
   
   
   • POF: Thin yet tough, uniform thickness, excellent moisture resistance, soft texture, high tensile strength, strong tear resistance, adjustable shrinkage rate, and superior wrinkle resistance due to the addition of LLDPE.
   • PE: Thick yet tough, uniform thickness, excellent moisture resistance, soft texture, tear resistance lower than POF but much higher than PVC, poor shrinkage adjustability, and inferior wrinkle resistance compared to POF.
   • PVC: Thick and brittle, uneven thickness, poor moisture resistance, hard and brittle texture, low strength, low shrinkage rate, and poor wrinkle resistance.

4. Low-Temperature Resistance & Other Properties:

   
   
   
   • POF: Excellent low-temperature resistance (-50℃), remains non-hard and non-brittle without cracking, suitable for frozen food packaging. After shrink wrapping, packaged items can be stored stably at -50℃ to 95℃ for a long time. Treated with anti-static and anti-fog coatings, it is not easy to attract dust, keeping products clean and bright.
   • PE: Superior low-temperature resistance, remains non-hard and non-brittle in winter or after freezing, making it less likely to crack during transportation. Treated with anti-static coating, it is not easy to attract dust, maintaining product cleanliness.
   • PVC: Extremely poor low-temperature resistance, becomes brittle in winter or after freezing, leading to easy cracking during transportation. The shrinkage tightens over time, causing deformation of packaged items. Without anti-static treatment, it easily attracts dust, resulting in product contamination and dullness.

5. Processing Performance:

   
   
   
   • POF: No moisture generation during processing, no adhesion to sealing bars, easy maintenance and operation. Its high toughness, smoothness, and wrinkle resistance make it suitable for automatic packaging on high-speed production lines.
   • PE: No moisture generation during processing, no adhesion to sealing bars, easy maintenance and operation. With high toughness and low wrinkle resistance, it can be used for automatic packaging on relatively high-speed production lines.
   • PVC: Volatile substances are generated during processing, which easily damage machinery and adhere to sealing bars, causing inconvenient operation and difficult maintenance.

6. Safety:

   
   
   
   • POF: After shrink wrapping, the four corners of the seal are soft, won't cut hands, and are wrinkle-resistant.
   • PE: After shrink wrapping, the four corners of the seal are soft, won't cut hands.
   • PVC: After shrink wrapping, the four corners of the seal are hard and sharp, prone to cutting and causing bleeding.

7. Environmental Friendliness & Hygiene:

   
   
   
   • POF: Non-toxic, no toxic odors generated during processing, compliant with US FDA and USDA standards.
   • PE: Non-toxic, no toxic gases generated during processing, compliant with US FDA and USDA standards.
   • PVC: Toxic, generates odorous and toxic gases during processing, and is being gradually phased out.

Article Title: Key Considerations When Purchasing Heat Shrink Bags URL: https://en.szxylp.com/technical-data/key-considerations-when-purchasing-heat-shrink-bags.html