Patent ID: 6214447
Filing Date: 2001-04-10
Classification: B32B,C08J,C08L,C09J,Y10S,Y10T

Abstract:
A composite film comprising a substrate film and, laminated onto at least one side thereof, a 2 to 200 .mu.m thick resin layer of a laminating propylene/1-butene random copolymer composition comprising 50 to 97% by weight of a propylene/1-butene random copolymer (A) and 50 to 3% by weight of a low-density polyethylene (B),said propylene/1-butene random copolymer (A):(1) comprising 50 to 95 mol % of structural units derived from propylene and 5 to 50 mol % of structural units derived from 1-butene;(2) exhibiting a melt flow rate (measured at 230.degree. C. under a load of 2.16 kg in accordance with ASTM D 1238) of 0.1 to 40 g/10 min;(3) having a molecular weight distribution (Mw/Mn), measured by gel permeation chromatography (GPC), of up to 3; and(4) having a B-value, being a parameter indicating a randomness of copolymer monomer chain distribution, of 1.0 to 1.5, andsaid low-density polyethylene (B):(1) exhibiting a melt flow rate (measured at 190.degree. C. under a load of 2.16 kg in accordance with ASTM D 1238) of 1 to 30 g/10 min; and(2) having a density of not greater than 0.940 g/cm.sup.3.