ASO Co., Ltd.

 Recently, multilayer technology has been actively applied to plastic bags. In this technology, multiple circular dies are installed during inflation to extrude the resin in a multilayer state, and the films are heat-welded together while the resin is still crystallizing. The film appears as a single sheet, and the multilayer structure cannot be identified by the naked eye.

 However, when the cross-section is observed under a polarizing microscope, the overlapping layers become visible. This technology is employed when conventional LDPE or HDPE bags alone cannot meet the required specifications. By multilayering, a new film can be created that combines the advantages of each material.

 Additionally, it is possible to produce plastic bags with excellent opening properties by placing HDPE on the inside, or bags with superior slip properties by placing HDPE on the outside. In some cases, the same LDPE is used to produce multilayered bags for beverages. For such applications, the inner layer in contact with the product is made from additive-free or low-odor film, while the outer layer uses metallocene-catalyzed film with high pinhole resistance.