Patent ID: 7341794

Claim:
A process for producing a laminated film which comprises: melt extrusion laminating, without using an anchor coating agent, an ethylene based resin comprising a linear ethylene/α-olefin copolymer having a density of from 0.870 to 0.910 g/cm 3 ; and a melt flow rate (MFR) of from 1 to 100 g/10 min., wherein the copolymer is obtained by copolymerizing ethylene and an α-olefin having from 3 to 20 carbon atoms, on the surface of a propylene based resin film formed from a crystalline propylene based random copolymer resin having a melting peak temperature of not higher than 140° C., wherein the crystalline propylene based random copolymer resin is prepared using a metallocene catalyst; wherein the crystalline propylene based random copolymer resin has a ratio (ΔHm 130 /ΔHm), defined as the heat of fusion up to 130° C. (ΔHm 130 ) divided by the whole heat of fusion (ΔHm), of 0.5 or more, and wherein the laminated film has an interlaminar adhesive strength of 60 g/15 mm or more.