Patent ID: 7722794

Claim:
A method of manufacturing a surface-treated laminate film comprising (a) a surface treated polyolefin-containing resin layer having a flame or corona treated surface and (b) a heat sealable resin layer that is not directly on the flame or corona treated surface, the heat sealable resin layer having a storage shear modulus of 400,000 Pa or less at 100 rad/s at 121° C., 100,000 Pa or less at 10 rad/s at 121° C., and 5000 Pa or less at 1 rad/s at 121° C., and a melting temperature of 73° C.-89° C., the method comprising: coextruding a laminate film comprising at least a polyolefin-containing resin layer and a heat sealable resin layer and simultaneously stretching the coextruded laminate film in machine and transverse directions of the laminate film; and then surface treating the laminate film to produce a surface-treated laminate film, whereby the surface-treated laminate film has tensile properties in a machine direction of the laminate film including a Young's modulus of 350,000 psi (2,413,165 kPa) or more, an elongation of 120% or less, and a tensile strength of 27,000 psi (186,158 kPa) or more.