What kinds of materials does a food package consist of?
There are many kinds of plastic bags commonly used in food packaging in our life, such as potato chips, instant noodles, plastic bags for breakfast foods, plastic cups for drinking water and lunch boxes for eating, all made of different materials.Now let's talk about some of the ingredients that are used in food packaging.
Food packaging material basically has: PVDC (polyvinylidene chloride), PE (polyethylene), PA (nylon), EVOH (ethylene/vinyl alcohol copolymer), aluminum plating film (aluminum + PE), and other materials, these materials are safe and non-toxic, general is not a food packing bag with a single material, usually of multilayer composite.
For example, the vacuum food packaging bag is composed of NY+PE, which is suitable for low temperature (-20 degrees) and has the best vacuum effect
But there is also a single layer of food packaging, such as the red casing of ham sausage is a single material PVDC.PVDC is a kind of high barrier property and strong toughness, and low temperature heat sealing, heat shrinkage and chemical stability, good ideal packaging materials, in the packaging industry, especially its dampness, the oxygen resistance, moisture resistance, acid and alkali resistance, resistance to oil and various chemical solvents, such as performance, over the past 50 years is widely used in food, medicine, military packaging.
However, most of the packaging bags are not single material, generally the inner layer is PE, the outer layer is PA, and the middle may be EVOH, or PVDC, some of which are coated with aluminum film.
Reason: PE has better thermal seal, which is easy to seal
PA is a good printing, used in the outer layer, can print beautiful pictures.
PVDC and EVOH have good barrier property and prevent oxidation.Aluminum - plated film of good.