My country is a big country in the production and consumption of food. For example, fruits are rich in fruit sources, but the rotten rate is relatively high. The loss rate of fruits in developed countries is less than 5%, while the loss rate in my country is as high as 20%. Due to the lack of post-harvest processing technology, The annual economic loss is as high as 70 billion yuan, and it is urgent to raise the packaging requirements of various industries.
At present, there are many kinds of packaging materials used in our country, and different materials have different advantages. At present, our country has increasingly strict requirements on various parameters of packaging, and different countries have introduced 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. 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, smoother 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 kind of 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 not easy to print. 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.
Sixth: PA/Nylon
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 ultra-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, and low adhesion viscosity. It is easy to transfer the aluminum coating after composite processing.
Many of the above materials are transparent materials. Generally, it is not obvious to the naked eye that they are different. Only by understanding the performance can we know which aspects they are suitable for.
Guangzhou Biaoji focuses on the research and development of packaging testing instruments, providing customers in the packaging, food, pharmaceutical and other industries with packaging testing instruments such as water vapor transmission rate testers, gas transmission rate testers, oxygen transmission rate testers, mask filtration testers, etc. , Guangzhou Biaoji-your trusted packaging testing instrument manufacturer.
