Views:0 Author:Site Editor Publish Time: 2021-11-18 Origin:Site
At present, my country uses a variety of packaging materials, and different materials have different advantages. At present, my country has increasingly strict requirements on various parameters of packaging, and different countries have introduced different countries for the oxygen permeability, moisture permeability and air permeability of packaging. standard.
The first type: HDPE/high density polyethylene/low pressure polyethylene/low pressure film
This is the most common material, which is the kind of shopping bags that we often see in supermarkets. It is made of our HDPE bags. This material can be made into bags separately, and it is a kind of shopping bag on the market. A relatively common and cheap material-PO bag. This kind of material is relatively brittle, harder, has a low expansion rate, and has a crisper sound when rubbed.
The second type: LDPE/low density polyethylene/high pressure polyethylene/high pressure film
Transparent texture, softer, good toughness, good transparency, smooth hand feeling, the thicker and harder the material, the greater the expansion rate. This kind of material can also be made into a bag separately, and it is a relatively common and cheap material like the PO bag.
The third type: OPP/oriented polypropylene
This material is the most brittle and most transparent material. The tension is not enough. It can be said that there is no tension at all. The single is the most violent, and the printing is the easiest to discolor. It is very difficult to print, and it needs to be printed for a period of time. Is cutting the bag,
The fourth type: CPP/cast polypropylene/unstretched polypropylene
This material has high transparency, higher hardness and clearer than PE film, and is a long base film for composite materials. It is often combined with other films to form a bag, which is a good composite film. CPP also has a cooking grade material that can be used for food that needs to be steamed.
The fifth type: PET/polyethylene terephthalate
The transparency of this material is also very good, the strength and toughness are better than polystyrene and polyvinyl chloride, it is not easy to break, and the surface is smooth and shiny. It is also one of the common composite materials.
This material is often used as a composite material for cooking/poaching bags, with good toughness and softness.
Seventh type: aluminum foil/AL
Aluminum foil is an extremely thin sheet formed by rolling high-purity aluminum several times. It is an excellent heat conductor and light-shielding body. Good mechanical strength, light weight, no thermal adhesion, metallic luster, good light-shielding, strong reflection to light, not easy to be corroded, good barrier properties, moisture-proof and waterproof, strong air tightness, and fragrance retention . It has metallic luster, high gas barrier properties, low adhesion viscosity, and the phenomenon of aluminum coating transfer is prone to occur after composite processing.