Film blowing machine is a mechanical device that heats and melts plastic particles and then blows them into film. Its core process includes melting plastic resin, extruding it into a molten plastic tube through a mold, inflating it, cooling and solidifying it, and winding it into a roll. This series of processes is called film blowing extrusion, which aims to produce plastic films with uniform thickness and high quality.
The films produced by film blowing machines are widely used in various high-end film packaging, such as packaging of various fresh fruits, meat products, pickles, fresh milk, liquid beverages, medical supplies, etc., because of their good barrier properties, freshness preservation, moisture resistance, frost resistance, oxygen isolation, and oil resistance. Depending on the material and characteristics, the films produced by film blowing machines can be divided into many types, including:
LDPE (low-density polyethylene) film: It is widely used in packaging fields such as food, detergents, etc. due to its good transparency, softness and toughness.
HDPE (high-density polyethylene) film: It has excellent strength, moisture resistance and chemical resistance, and is often used in heavy packaging and construction industries.
LLDPE (Linear Low-Density Polyethylene) Film: It combines the softness of LDPE with the strength of linear low-density polyethylene, and is suitable for packaging foods such as meat and cheese.
PP (Polypropylene) Film: It is known for its heat and chemical resistance and is often used in the packaging of snacks, candies, etc.
PVC (Polyvinyl Chloride) Film: It is transparent and soft, suitable for the packaging of meat, cheese and medical supplies.
EVA (Ethylene-Vinyl Acetate Copolymer) Film: It is soft and flexible and is widely used in industrial fields such as shoes and clothing, solar cells, etc.
In addition, in order to meet the needs of some special functions of plastic film packaging materials in the production process, people blow and co-extrude a variety of characteristic materials (such as breathable, waterproof, heat-insulating, toughness, etc.) together to form a multifunctional plastic film, so a multi-layer co-extrusion film blowing machine was developed. Multi-layer co-extrusion film blowing machines are divided into two-layer co-extrusion film blowing machines, three-layer co-extrusion film blowing machines, five-layer co-extrusion film blowing machines, etc., aiming to give full play to the advantages of multiple materials and avoid some disadvantages of a single material or a single-layer film blowing machine.
