Shrink film provides more than just surface protection for products

Shrink film provides surface protection for the product, which is one of the biggest characteristics of shrink film packaging. With the help of the film's super winding force and retraction, the product is compactly and fixedly bundled into a unit, so that the scattered and small pieces become a whole, even in unfavorable environments, the product does not have any scattering or separation, and there is no sharpness. The edges and stickiness to avoid damage. Primary protection: Primary protection provides surface protection of the product, forming a very light protective appearance around the product, so as to achieve the purpose of dust, oil, moisture, water, and theft prevention. It is particularly important that the stretch film packaging makes the packaged items evenly stressed and avoids damage to the items caused by uneven force, which is not possible with traditional packaging methods (bundling, packing, tape and other packaging). Shrink film compression fixity: the product is wrapped and packaged by the retraction force of the stretch film to form a compact unit that does not occupy space, so that the pallets of the product are tightly wrapped together, which can effectively prevent the transportation process The mutual dislocation and movement of the middle products, and the adjustable stretching force can make the hard products stick closely and shrink the soft products, especially in the tobacco industry and the textile industry, which have a unique packaging effect. Cost saving: The use of stretch film for product packaging can effectively reduce the cost of use. The use of stretch film is only about 15% of the original box packaging, about 35% of the heat shrinkable film, and about 50% of the carton packaging. At the same time, it can reduce the labor intensity of workers, improve packaging efficiency and packaging quality. material selection. The printing of shrink film labels has been briefly analyzed above. In addition to controlling the quality of the printing process, the material plays a decisive role. Therefore, choosing the right material is the key. So how to choose? (1) Material thickness. Determine the thickness of the film material according to the application field, cost, film characteristics, shrinkage performance, printing process and labeling process requirements of the heat shrinkable label. It is generally required that the film thickness of the shrink film label should be 30-70 microns, and the commonly used film specifications are 40 microns and 50 microns. (2) Material shrinkage rate. Generally, the shrinkage rate of the film is required to be within the application range, and the transverse direction (TD) shrinkage rate is higher than the longitudinal direction (MD) shrinkage rate. The transverse shrinkage rate of common materials is 50%-52% and 60%-62%, and can reach 90% under special circumstances. The longitudinal shrinkage rate is required to be between 6% and 8%. When making shrink film labels, try to choose materials with small longitudinal shrinkage. PVC, the full name is polyvinyl chloride, PVC heat shrinkable film itself is non-toxic, pure PVC resin itself is a non-toxic polymer, the reason why it is said to be toxic is because PVC film will release chlorine atoms in an environment above 65 degrees Celsius. The chlorine atom is poisonous. Therefore, when packaging food, food that needs to be heated or is too hot cannot use PVC. But PVC can be used for packaging candy and medicine, because it is not exposed to high temperatures, it can still be used. What you said about packing clothes and quilts is fine. It's just that nowadays, more PP films are used to pack clothes and quilts. Therefore, my country's standards stipulate that the unpolymerized vinyl chloride monomer content in the PVC resin for food packaging must be less than 5 ppm, and the unpolymerized vinyl chloride monomer content in the calendered PVC rigid sheet for food packaging must be controlled at 1 ppm. When the heat shrinkable film is heated, the irregular arrangement of the original molecules has changed. Under thermal radiation such as infrared rays, the plastic molecules are re-arranged tightly, which greatly reduces the original area. Generally used shrink materials are PVC, POF, PE, etc. At present, POF shrink film: the most widely used, with its high surface gloss, good toughness, high tear strength, uniform heat shrinkage and suitable for fully automatic high-speed packaging, etc., it is recognized by the majority of manufacturers for its good advantages in environmental protection, and it can also be called It is an environmentally friendly shrink film, so it has a wide range of applications; PVC heat shrinkable film: chemical name: polyethylene, a toxic material, not environmentally friendly, low toughness, gradually replaced by POF, generally suitable for chemical non-environmental protection industries; PE shrinkage Film: Generally, it is the most widely used in the beverage industry. Features: Good flexibility, impact resistance, strong tear resistance, not easy to break, not afraid of moisture, large shrinkage, suitable for heavy shrink film packaging. It is suitable for mass automatic shrink packaging items such as cans, glass bottles, beer, mineral water, etc.