公开(公告)号：JPS6418633A

公开(公告)日：1989-01-23

申请号：JP17483387

申请日：1987-07-15

Applicant: MITSUI PETROCHEMICAL IND

Inventor： SUGI MASAHIRO ,  KIOKA YUZURU ,  TOYODA AKINORI

IPC: B32B27/32 ,  C08L23/00 ,  C08L23/14

Abstract: PURPOSE:To improve low temp. heat-seal characteristics and heat-seal strength, by laminating a layer consisting of a specific low crystalline propylene copolymer composition on one face of a base material layer consisting of crystalline polypropylene. CONSTITUTION:Low crystalline propylene copolymer composition has such a composition that propylene (a), ethylene (b) and alpha-olefin (c) are in the ranges of 86-97, 0.5-6 and 2-13mole% respectively, and the molar ratio c/(b+c) is 0.3-0.9. The composition is formed with 60-95wt.% copolymer whose intrinsic viscosity [eta] measured in decalin at 135 deg.C is in the range of 0.5-6dl/g, m.p. [Tm] measured by means of differential scanning calorimeter is in the range of 115-145 deg.C and crystallinity measured by means of X-ray diffraction method is in the range of 30-60%, and 5-40wt.% of copolymer consisting of 10-90mole% of propylene (d) and 10-90mole% of 4-20 alpha-olefin.