Production process and selection knowledge of PVC in heat shrinkable film

PVC heat shrinkable film allows customers to directly see the packaged products, which is convenient for customers to choose products; Close to the shape of the product, it can be applied to the packaging of products with various shapes, and the contents of the packaging are universal; Anti-theft and dustproof are good; A variety of products can be packaged in a heat-shrinkable packaging bag, which avoids the loss of a single small product and is convenient for customers to carry; Choosing different resins and formulas can produce environmentally friendly shrink films with different mechanical strength and functions, which can be used for inner packaging with low strength and small product weight, and also for transport packaging (outer packaging) of mechanical products for containers with good demand strength and construction materials.

In the production process of PVC heat shrinkable film, it is easy to cool after being stretched in a high temperature environment, and then it reaches the setting intention. When it is heated again during use, it retracts its posture, and the heating is uneven, and the shrinkage degree and planning are not the same. At first, PVC heat shrinkable film is made by extrusion blow molding or extrusion tape casting, then it is fully softened at the melting temperature, and then it is stretched horizontally and vertically.

PVC is widely used in packaging industry in heat shrinkable film because of its water-stopping, safety, relatively low cost and so on. However, due to the difficulty of PVC heat shrinkable film molding, a large amount of plasticizer needs to be added. Under high temperature and excellent environment, the plasticizer and vinyl chloride monomer in PVC heat shrinkable film will dissolve out, and it will cause hidden dangers to consumers' health if it is directly contacted with food packaging.

The full name of PVC heat shrinkable film is multi-layer coextruded polyolefin PVC heat shrinkable film, which is made of linear low-density polyethylene (LLDPE) as the middle layer and polypropylene (pp) as the inner and outer layers, plasticized and extruded by three extruders, and then processed by special processes such as die forming and film bubble inflation.

The advantages of heat shrinkable polyester film packaging are:

(1) body-fitted transparent, reflecting the image of goods.

② Tight packing, good anti-scattering.

(3) rain.

(4) no resilience, with some anti-counterfeiting functions.

Heat shrinkable polyester films are often used in convenience food, beverage market, electronic appliances and metal products, especially shrink labels. Because with the rapid development of PET beverage bottles, such as cola, sprite, all kinds of fruit juice and other beverage bottles need PETPVC heat shrinkable film to be matched with them for heat sealing labels. They belong to polyester, are environmentally friendly materials, and are easy to recycle.

PVC heat shrinkable film label is a part of the label market, which is growing rapidly and its market share is constantly expanding. It is estimated that the annual growth rate will be around 15%, which is 5% higher than that of the ordinary label market. It has great development potential and has become a bright spot in the label printing industry. It is predicted that the domestic heat shrinkable film market will grow at a rate of more than 20% in the next five years.

PVC heat shrinkable film is made by mixing PVC resin by ethylene method with more than a dozen auxiliary materials and then inflating for the second time. Its use method is to calculate the circumference according to the size of the wrapped object, convert the folding diameter (folding diameter =1/2 circumference), and then appropriately enlarge the folding diameter.

PVC heat shrinkable film selects proper PVC heat shrinkable sleeve film according to the product specifications of our factory. Install the sleeve film on the package at the temperature of 100℃-160℃ for 6-10 seconds (the actual temperature of the sleeve film is 86℃, and the temperature rise of the package is less than 10℃).

(1), shrink film performance is good, but also has a good strength, accept the weight of the contents.

② heat shrinkable film has high transparency, so the label has bright color and good luster.

(3) heat shrinkable film can provide 360-degree decoration for packaging containers, and can print commodity information such as product clarification on labels, so that consumers can understand the performance of products without opening the packaging.

④ Heat-shrinkable packaging can package special-shaped products that are difficult to package by ordinary methods.

⑤ The heat shrinkable film clings to the goods after contraction, and the packaging is compact and can show the appearance of the goods, and the packaged goods are beautiful.

⑥ Heat-shrinkable packaging has good sealing, anti-fouling and anti-rust effects, which can prolong the storage period of food and facilitate storage and open-air stacking.