A METHOD FOR FORMING A PEELABLE CONNECTING STRUCTURE

摘要

Provided is a connecting structure in which a material can be easily separated with easy control for a peeling process and high pressure resistance, and a bi-axially oriented polypropylene film is not easily torn during a peeling process when the bi-axially oriented polypropylene film is used for manufacturing a cap of a container made of a thermoplastic resin material. The method for forming the connecting structure of the present invention is to enable a bi-axially oriented sheet(A) containing a sealant layer(A2) and a thermoplastic resin material(B) containing a sealant layer(B2) to be heat-sealed and form the connecting structure having the peeling effect on the heat-sealed part. Polypropylene random copolymer(PPA) is included in the sealant layer(A2) of the bi-axially oriented sheet(A), and low melting polypropylene random copolymer(PPB) is included in the sealant layer(B2) of the thermoplastic resin material(B). The difference between the weight of the PPA in propylene unit and the weight of the PPB in propylene unit is within ±5% in (PPA-PPB)/PPB×100(%).