Properties difference between POF shrink film,traditional PE shrinkage film and PVC shrinkage film
1. Physical performance
POF is thin and tough, with uniform thickness, excellent optical,high toughness,high and balanced shrinkage rate, and good coefficient of friction to enable high speed packaging.
Traditional PE film has high gauge which is at least 2 times than POF due to its low toughness It’s thickness variation is also higher than POF, optical properties is also inferior ,it has low and unbalanced MD/CD shrinkage rate.
PVC film thickness is at least double of POF , it has uneven in thickness, poor physical properties and tend to become brittle in low temperature ;its shrinkage rate is also lower than POF.
2. Packaging appearance
Clarity gloss and haze of POF is much better than traditional PE film and PVC shrinkage film. It has high and balanced shrinkage rate and can closely contact surface of the packaged products which functions like a colorless skin of packaged products.
Traditional PE shrinkage film had low gloss and high haze and have to leave two big hole in two side of packaged products due to its low and unbalanced shrinkage rate.
PVC shrinkage film also have poor transparency and normally leave a few very big sharp ear near seal corners due to its low shrinkage rate and hard film property. PVC film continues shrinkage with time and tend to distort the packaged products with time. A lot of plasticizer is added in PVC film formula and it will gradually migrate to film surface and absorb dust and makes the film surface very dirty.
3. Low temperature resistance
POF film has good cold resistance, can maintain its toughness at -50 ℃, and is not easy to crack. It can be used for frozen food packaging. After shrinkage, the packaged products can store for a long time between -50 C and 40 C with packaging integrity.
Traditional PE heat shrink packaging is prone to crack during transportation due to its lower toughness. It is brittle after freezing in winter, making it prone to break during transportation.
PVC shrink film has poor cold resistance,it is fragile during winter or freezing, and prone to break during transportation.
4. Packaging performance
POF does not generate gas upon heat seal during packaging process and does not stick to the seal bar, and is easy to maintain and operate. Its high toughness, good film thickness variation and low coefficient of friction make it suitable for automatic packaging on high-speed production lines;
Traditional PE film does not generate gas upon heat seal during packaging line and also does not stick to seal bar, it is easy to maintain and operate. it has reasonable toughness, low blocking performance which makes it suitable for automatic packaging on high-speed packaging lines;
PVC film generates harmful gases upon heat seal during packaging process which do not meet environmental requirements and can also cause mechanical damage. At same time , it tends to to stick to seal bar, which is inconvenient to operator, and difficult to maintain.
5. Security
After packaging, the four corners of POF film of the seal are small and soft, which is not harmful to hands, and also been resistant to friction;
The four corners of the seal of traditional PE shrinkage film are also soft and won't hurt hands;
However,the four corners of the seal of PVC shrinkage film are hard and sharp, which can easily hurt hands.
6. Environmental protection and hygiene
Both POF and traditional PE film are non-toxic and has no toxic odor during film production and packaging process which complies FDA standard
PVC film is toxic and produce harmful odors during film making and packaging process,so it is gradually been banned in many countries