Production process of biaxially oriented flat extrusion for stretch film?

Production process of biaxially oriented flat extrusion for stretch film? Suzhou enjiadi Intelligent Equipment Co., Ltd

Biaxially oriented polypropylene film (BOPP) is a kind of multilayer copolytic film, which is made of polypropylene particles by coextrusion and then stretching in both vertical and horizontal directions. Due to the orientation of stretching molecules, this kind of film has good physical stability, mechanical strength, air tightness, high transparency and gloss, tenacity and wear resistance. It is a widely used printing film at present, with a thickness of 20-40 μ m in general and 20 μ m in wide application. The main disadvantage of biaxially oriented polypropylene film is poor heat sealing, so it is generally used as the outer layer of composite film. For example, the moisture resistance, transparency, strength, stiffness and printability of composite film with polyethylene film are ideal, which is suitable for holding dry food. As the surface of biaxially oriented polypropylene film is non-polar, high crystallinity and low surface free energy, its printing performance is poor, and its adhesion to ink and adhesive is poor, so surface treatment is needed before printing and compounding.