Plastic is a synthetic or natural polymer resin as the main material. After adding various additives, at a certain temperature and
pressure is malleable, a class of materials which can be fixed shape after cooling. Natural or synthetic polymer resin molecules
in the molten state, and evenly distributed around the molecular process is called plasticizing additives have already reached
this process is called a plasticizer, is not reached, the plasticizer is not yet considered. Plastic packaging materials is one of
the four packaging industry: 30% of paper and paperboard, plastics accounted for 25%, metals 25%, 15% glass.