The production method of stretch film

The production method of stretch film

The forming and processing of stretch film refers to the process of making the final plastic product from the polymer made by the manufacturer of synthetic resin. The processing methods (usually referred to as the primary processing of stretch film) include extrusion (molding by moulding), extrusion (extrusion molding), injection (injection molding), blow molding (hollow molding), rolling, etc.

moldingCompression molding is also called moulding or pressing molding, which is mainly used for the forming of thermosetting plastic stretch film such as phenolic resin, urea-formaldehyde resin and unsaturated polyester resin.

extruded

Extrusion, also known as extrusion molding, is the use of the extruder (extruder) to heat the resin through the mold continuously, extrusion of the required shape of the product. Extrusion sometimes also has thermosetting plastic molding, and can be used for forming stretch film. The advantage of extrusion is that it can extrude all kinds of products of various shapes, with high production efficiency, automatic and continuous production. The disadvantage is that thermosetting plastics can not be widely used in this process, the size of products are prone to deviation.Injection moldingInjection molding or injection molding. Injection molding is the method of using injection molding machine (or injection machine) to inject the thermoplastic melt into the mold under high pressure and obtain the product through cooling and curing. 

Injection molding can also be used in the formation of thermosetting plastics and foam plastics. Injection molding has the advantages of fast production speed, high efficiency, automatic operation, can form complex shape parts, especially suitable for mass production. The disadvantage is high equipment and mold cost, injection molding 

machine cleaning more difficult.

Blow molding

Blow molding also known as hollow blow molding or hollow molding. Blow moulding is a method to make the hot resin blank in the mould blown up into hollow products by the pressure of 

compressed air. Blow moulding includes blow moulding stretch film and blow moulding hollow products. Blow molding method can be used to produce film products, various bottles, barrels, POTS containers and children's toys.

rolling

Calender is the resin and various additives after expected processing (kneading, filter, etc.) by two or more calender to instead of the calender roll gap processed into stretch film or sheet, then falls off from the calender roller, then through cooling finalize the design of a forming method. Calender is mainly used for the molding of polyvinyl chloride resin, which can produce stretch film, sheet material, sheet material, artificial leather, floor tile and other products.

Foam molding

Foaming materials (PVC,PE, PS, etc.) are added with appropriate foaming agents 

to enable the formation of micropore structure in plastics. Almost all thermosetting and thermoplastic plastics can be made into foam plastics. According to the bubble pore structure is divided into hole foam (sleep most of the air hole connected each other) and closed-cell foam (most of the porosity is separated from each other), mainly by the manufacturing method (divided into chemical foaming, physical foaming and mechanical foaming).