| 摘要 |
PROBLEM TO BE SOLVED: To enhance lapping properties, overlay processing properties and V-cut processing properties by specifying the ultimate viscosity of one of the components of a propylene-α-olefin random copolymer having different propylene contents, the ratio of the ultimate viscosities of both components and the product of the ratio of the ultimate viscosities and the weight ratio of the both components. SOLUTION: An olefin resin layer is composed of a propylene-α-olefin random copolymer component A having the propylene content of 90 wt.% or more and a propylene-α-olefin random copolymer component B having the propylene content of 55-90 wt.%. A propylene block copolymer having the ultimate viscosity of 1.3-3.5 dl/g of the propylene-α-olefin random copolymer component B, the ratio of the ultimate viscosities of these random copolymer components A, B of 0.5-1.3, and the product of the ratio of the weights of the random copolymer components A, B and the ratio of these ultimate viscosities being in the range of 1.0-4.5, is used as the olefin resin layer for a base sheet 1.
|
