In order to keep food fresh and store food in production and life, it is necessary to use food packaging bags of various materials to contain and protect food. Food packaging bags are usually made of single-layer or multi-layer composite film materials that meet the food and drug hygienic quality standards.
Therefore, food production enterprises should match the selection of automatic food packaging machinery and equipment and packaging materials according to their own product characteristics, bag type requirements, specification design, etc. in order to achieve the purpose of increasing efficiency, improving quality and reducing costs.
1. The type and composition of the film material used in the food packaging machine
The main materials of food packaging bags used in vertical packaging machines are PVDC (polyvinylidene chloride), PE (polyethylene), PP (polypropylene), PA (nylon), EVOH (ethylene/vinyl alcohol copolymer) ), aluminized film (aluminum + PE) and other major films, mainly used for food packaging bags are PP and PE, namely polypropylene and polyethylene plastics, composite films usually consist of inner, middle and outer layers of different materials .
①, Inner layer material: The inner layer material should be selected with heat-sealability, good adhesion, odorless, non-toxic, oil-resistant, water-resistant, chemical-resistant and other properties such as polypropylene, polyethylene, polyvinylidene chloride and other heat-resistant properties plastic material.
②. Middle layer material: The middle layer of composite materials with more than three layers is usually made of materials with good performance and high mechanical strength, such as aluminum foil, polyvinylidene chloride, cellophane, paper, polyethylene, etc.
3. Outer layer material: The outer layer material of the composite packaging material should be a material with a high melting point, good heat resistance, not easy to scratch, sand, good printing performance, and good optical performance. Paper, aluminum foil, cellophane are often used. , polycarbonate, nylon, polyester, polypropylene, etc.
