Patent ID: 7582352

Claim:
A foamed laminate based on olefin in which a substrate layer is laminated with a non-foamed skin layer, wherein the foamed laminate is a co-extruded product in which the substrate layer and the skin layer are heat fused and the substrate layer is foamed by co-extrusion by multilayer extrusion molding machine, wherein said substrate layer comprises a foamed body (X F1 ) comprising an uncrosslinked ethylenic thermoplastic elastomer (A) comprising 5-60 parts by weight of a polyethylene resin (a-1) and 40-95 parts by weight of a copolymer based on ethylene/α-olefin (a-2), with said constituents (a-1)and (a-2) summing up to 100 parts by weight, and said skin layer comprises an ultrahigh molecular weight polyolefin resin (Y), wherein said ethylenic, thermoplastic elastomer (A) consists of a thermoplastic elastomer obtained by subjecting a mixture of the polyethylene resin (a-1) and the copolymer based on ethylene/α-olefin (a-2) to a dynamic heat treatment in the absence of a cross-linking agent, and wherein said copolymer based on ethylene/α-olefin (a-2) is a copolymer of ethylene, an α-olefin and, optionally incorporated, non-conjugated polyene and has a Mooney viscosity ML 1+4 (100° C.) of 90-250 and an ethylene content of 70-95 mole %, and wherein the ethylenic thermoplastic elastomer (A) is one which has a compression set of 60% or less as determined according to JIS K 6262 (at 70° C., 22 hours) and a melt flow rate of 0.1 g/10 min. or higher as determined according to JIS K 7120 (at 230° C., 10 kg load), and wherein the foamed body (X F1 ) is formed by subjecting a foamable ethylenic thermoplastic elastomer composition (X 1 ) comprising the ethylenic thermoplastic elastomer (A) and 0.5-20 parts by weight of an organic or inorganic foaming agent of a heat decomposition type (B) per 100 parts by weight of the ethylenic thermoplastic elastomer (A) and the foaming agent (B) to foaming by co-extrusion with the foaming expansion ratio of the foamed body (X F1 ) of at least twofold, and wherein the foamed laminate is formed by co-extrusion of the foamable ethylenic thermoplastic elastomer composition (X 1 ) and the ultrahigh molecular weight polyolefin resin (Y) wherein the foamable ethylenic thermoplastic elastomer composition (X 1 ) foams by heat fusing to form the substrate layer of the foamed body (X F1 ), and wherein said ultrahigh molecular weight polyolefin resin (Y) is one which has an intrinsic viscosity (η) of 3.5-8.3 dl/g as determined in decalin at 135° C.