Requirements for milk packaging bags
Milk, which everyone is familiar with and often enjoys, is taken from cows. It is a fresh drink that has very strict requirements on hygiene, bacteria and temperature, and also has very special requirements for packaging containers. Printing, which is recognized as one of the culprits of pollution, is an indispensable part of packaging and has a major safety factor. Therefore, the printing technology requirements for milk packaging bags are particularly stringent, and the response requirements must be met.
As for the selection of milk packaging film, it must meet the requirements of packaging and printing, processing, storage and transportation, and hygiene. At present, the commonly used film material is mainly polyethylene (PE) co-extruded film, which is a polyethylene resin through melt extrusion and blow molding.
According to the layer structure of the film, milk packaging films can be basically divided into three types, namely simple packaging film, three-layer black and white co-extrusion packaging film, and five-layer black and white co-extrusion packaging film.
Generally, it is a single-layer film, which is produced by various polyethylene materials added with a certain proportion of white masterbatch through film blowing equipment. This kind of packaging film has a non-barrier structure and uses pasteurization (85°C/30min) for hot filling, with a short shelf life (about 3 days).