According to the material, there are express plastic bags, express document seals, express bubble bags, express bone bags, express woven bags, etc.
1. Material of express plastic bags: Low-density polyethylene (LDPE) is usually called PE, high-density polyethylene (HDPE) is usually called PO. Express plastic bags have the advantages of low cost and light weight.
The difference between PE and PO in express plastic bags: PE has better transparency and softness, and the printing color is brighter; PO has relatively good mechanical properties; domestic express bags generally use PE as the main material, while foreign countries generally use PE. PE and PO composites are used as the main material of express bags.
There are two types of polyethylene courier bags on the market: one is brand new material courier bags, the other is recycled material courier bags
2. The material of the express document seal: generally gray-bottomed whiteboard, white cardboard, kraft cardboard, mostly. The express delivery industry generally uses paper with a weight of 200 g/m2 to 450 g/m2. The express document seal has the advantages of being flatter and less likely to be broken than express plastic bags.
3. Express bubble bag material: a transparent soft packaging bag filled with air in the middle layer of the air cushion film. It is mainly used for the packaging of small, fragile, easily damaged, and less precise goods in the express industry. The express bubble bag is equipped with a shock-absorbing bubble film. There are countless small bubbles in the bubble film, so it is light in weight, full of elasticity, has good shock absorption, impact resistance, and has the advantages of non-toxic, odorless, moisture-proof, and corrosion-resistant.
4. Express bone bag material: bone bag (also known as dense bag, youren bag, sealed bag, zipper bag, ziplock bag, English: Ziplock bags, Reclosable Bag, Zipper Closure Bag, Resealable Bag), polyethylene ( LDPE) and high-pressure linear polyethylene (LLDPE) are formed by blown film, hot-cut machine-made bags, and made of a re-sealable plastic bag. Bone bags can be used for inner and outer packaging of various small items. Ziplock bags made of food-grade raw materials can store various small foods, tea, seafood, etc., moisture-proof, waterproof, insect-proof, and prevent things from scattering.
5. Express woven bag: also known as snakeskin bag. It is a kind of plastic, used for packaging, and its raw materials are generally various chemical plastic materials such as polyethylene and polypropylene. The color of the woven bag is generally white or off-white, non-toxic and tasteless, and generally less harmful to the human body. Although it is made of various chemical plastics, it is environmentally friendly and recyclable; it is mainly used for various It is used for packaging and packaging of articles and is widely used in industry.