POF Heat Shrink Film Production Process: A Complete Guide...
Production Process:
A Complete Guide
In the packaging industry, environmentally friendly POF heat shrink film (Biaxially Oriented Polyolefin Shrink Film) has become the preferred packaging material for food, daily chemical, electronics and other fields, thanks to its advantages of high transparency, high shrinkage rate and environmental safety. For packaging procurement managers, industry production managers, foreign trade buyers and packaging engineers, understanding the POF heat shrink film production process is the key to selecting high-quality POF heat shrink film — as a professional POF heat shrink film manufacturer, Zhejiang Zhongcheng will take you through the core production process, solve common pain points in procurement, and tell you why we can be your preferred partner.
When purchasing POF heat shrink film, many practitioners encounter problems such as uneven shrinkage, wrinkling and tearing, poor transparency, and non-compliant environmental protection. These issues not only affect packaging efficiency and increase losses, but may also fail to pass export compliance inspections. In fact, 90% of the quality of POF heat shrink film depends on the production process and raw materials. Zhejiang Zhongcheng uses food-grade Linear Low-Density Polyethylene (LLDPE) and Copolypropylene (PP) as raw materials, and adopts the industry's optimal double-bubble method (Prandi method) and three-layer/five-layer co-extrusion process to avoid these pain points from the source.
Core Production Process of POF Heat Shrink Film (Zhejiang Zhongcheng Standard Process)
Raw Material Selection and Ratio — Source of Quality
We select 100% food-grade LLDPE (core layer, flexible and impact-resistant) and copolypropylene (surface layer, high transparency and easy heat-sealing), reject recycled materials, and pass FDA, EU REACH and other compliance inspections to create high-quality three-layer/five-layer co-extruded POF heat shrink film. The layer thickness is accurately proportioned to balance strength, shrinkage and heat-sealing performance, ensuring environmental protection and quality from the source.
Multi-layer Co-extrusion Melting and Extrusion — Core of Forming
3 or 5 precision extruders work synchronously with precise temperature control at 190–230℃. The melted raw materials are seamlessly compounded through a special co-extrusion die to form a uniform primary film tube, eliminating interlayer separation and uneven thickness.
Primary Inflation + Rapid Cooling Setting — Key to High Transparency
After the primary film tube is inflated by high-pressure air, rapid water cooling at ≤10℃ locks the molecular structure, making the high-transparency POF heat shrink film have a transparency of ≥92% and a haze of ≤2%, far exceeding the products of ordinary manufacturers, and making the packaging more high-grade.
Secondary Heating + Biaxial Stretching — Core of Shrinkage Performance
Adopting the double-bubble method (Prandi method), after being softened by infrared heating, secondary inflation and synchronous biaxial stretching (longitudinal and transverse) are carried out, endowing the film with a high shrinkage rate of ≥50% in the transverse direction and ≥20% in the longitudinal direction. It is suitable for packaging irregular products, solves the problems of uneven shrinkage and deviation, and improves automatic packaging efficiency.
Cooling Setting + Corona Treatment — Adaptable to Printing and Heat-sealing
Cold air cooling locks the shrinkage performance, and surface corona treatment improves the surface tension, making the ink adhesion stronger and the heat-sealing more firm. It is suitable for various packaging scenarios and meets the needs of printing and compounding.
Slitting, Quality Inspection and Winding — Guarantee of Finished Products
Slitting is carried out according to requirements with a width of 15–2000mm and a thickness of 12–50μm. Full-process online inspection of shrinkage rate, heat-sealing strength and other indicators is carried out, 100% of unqualified products are eliminated, and packaging and delivery are completed in a clean workshop.
Why Choose Zhejiang Zhongcheng
Choosing Zhejiang Zhongcheng, you don't have to worry about the shortcomings of ordinary manufacturers: our five-layer co-extrusion double-bubble production line increases the toughness of POF heat shrink film by 30%, with a heat-sealing temperature range of 110–160℃, suitable for 99% of automatic packaging machines; 100% food-grade new materials + recyclable characteristics avoid export trade barriers; full-dimensional customization services + professional technical support help you reduce the comprehensive packaging cost by 15–25%, with sufficient stock and fast delivery.
+30%
Toughness vs. Standard Film
≥92%
Transparency
99%
Auto Packaging Machine Compatibility
-25%
Packaging Cost Reduction
Conclusion
Only by understanding the POF heat shrink film production process can you choose high-quality POF heat shrink film. With years of experience in the industry, Zhejiang Zhongcheng, as a professional POF heat shrink film manufacturer, has become the first choice of domestic and foreign enterprises with standard processes, excellent quality and intimate services, providing you with a one-stop packaging solution for high-transparency, food-grade POF heat shrink film.
Ready to upgrade your packaging line? Contact Zhejiang Zhongcheng today for free samples, custom specifications, and a dedicated technical consultation.