Popular Plastic Films in the World Currently

2019-01-01
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Summary :this article is a brief introduction to the plastic film.

Common film classification:


Biaxially Oriented Polypropylene Film (BOPP)

Biaxially oriented polypropylene film is made by polypropylene particles co-extruded to form a sheet, and then stretched in both the longitudinal and horizontal directions. Due to the orientation of the stretched molecules, this film has good physical stability, mechanical strength, air tightness, high transparency and gloss, toughness and abrasion resistance. It is currently the most widely used printing film, and generally uses a thickness of 20 ~ 40 μm, the most widely used is 20 μm. The main disadvantage of biaxially oriented polypropylene film is poor heat sealability, so it is generally used as the outer film of composite film. For example, it is ideal for moisture resistance, transparency, strength, stiffness and printability after compounding with polyethylene film. Contain dry food. Because the surface of the biaxially oriented polypropylene film is non-polar, has high crystallinity, and low surface free energy, its printing performance is poor, and its adhesion to inks and adhesives is poor. The surface needs to be printed before printing and compound deal with.


Low density polyethylene film (LDPE)
Low density polyethylene film is generally made by two processes: blow molding and casting. The thickness of cast polyethylene film is uniform, but it is rarely used because of its high price. Blow-molded polyethylene film is blown from blow-grade PE pellets through a blow-molding machine. The cost is low, so it is most widely used. Low-density polyethylene film is a translucent, shiny, soft film with excellent chemical stability, heat sealability, water resistance and moisture resistance, freeze resistance, and boilable. Its main disadvantage is its poor barrier to oxygen. It is often used as the inner film of composite flexible packaging materials. It is also the most widely used and most widely used plastic packaging film, accounting for more than 40% of the consumption of plastic packaging films. .

Because the polyethylene molecule does not contain polar groups, and has high crystallinity and low surface free energy, the film has poor printing performance and poor adhesion to inks and adhesives, so it is required before printing and compounding. Surface treatment.


Polyester film (PET)

Polyester film is a film material made of polyethylene terephthalate as a raw material, made into a thick sheet by extrusion, and then biaxially stretched. It is a colorless, transparent, glossy film with excellent mechanical properties, high rigidity, hardness and toughness, puncture resistance, friction resistance, high temperature and low temperature resistance, chemical resistance, oil resistance, air tightness, and fragrance retention. Good, is one of the commonly used barrier film substrates. However, the price of polyester film is relatively high, and the thickness is generally 12 μm. It is commonly used as the outer layer material for cooking and packaging, and has good printability.


Nylon film (PA)

Nylon film is a very tough film with good transparency and good gloss, high tensile strength and tensile strength, and also has good heat resistance, cold resistance, oil resistance, and organic solvent resistance. Excellent abrasion resistance, puncture resistance, and relatively soft, excellent oxygen barrier, but poor barrier to water vapor, moisture absorption, moisture permeability, heat sealability is poor, suitable for packaging rigid items, such as oil Sex foods, meat products, fried foods, vacuum packaged foods, steamed foods, etc.


Cast Polypropylene Film (CPP)

Cast polypropylene film is a polypropylene film produced by a casting process. It can be divided into two types: ordinary CPP and cooking grade CPP. It has excellent transparency, uniform thickness, and uniform vertical and horizontal performance. The thickness of ordinary CPP film is generally between 25 and 50 μm. After being combined with OPP, the transparency is good, the surface is bright, and a firm hand feels. General gift bags use this material. This film also has good heat sealability. The thickness of the cooking grade CPP film is generally between 60 and 80 μm, and it can withstand high temperature cooking at 121 ° C and 30 minutes. It has good oil resistance and air tightness, and has high heat seal strength. Use cooking grade CPP film.


Aluminized film
The most commonly used aluminized films are mainly polyester aluminized film (VMPET) and CPP aluminized film (VMCPP). Aluminized film has the characteristics of both plastic film and metal. The role of aluminum plating on the surface of the film is to block light and prevent ultraviolet radiation, which not only prolongs the shelf life of the contents but also improves the brightness of the film. It replaces aluminum foil to a certain extent, and also has low price, beautiful appearance and good barrier properties. Aluminized film is widely used in composite packaging. It is mainly used in the packaging of dry and puffed food such as biscuits and some medicine and cosmetics.