Abstract: A rubber laminate comprised of a cross-linked rubber layer containing a carboxyl-group containing nitrile copolymer rubber (A), a carboxyl-group containing acryl-based polymer (B), and a specific phosphonium salt and a fluorine-based polymer layer. Preferably, the carboxyl-group content per 100 grams of the (A) ingredient is 2×10?3 to 1×10?1 equivalents and the carboxyl-group content per 100 grams of the (B) ingredient is 4×l0?4 to 1×10?1 equivalents, the (A) ingredient and (B) ingredient are in a weight ratio of 40:60 to 90:10, and the phosphonium salt content in the cross-linked rubber layer is 0.5 to 10 parts by weight per 100 parts by weight of the total of the (A) ingredient and (B) ingredient. According to the present invention, there is provided a rubber laminate excellent in oil resistance and gasoline permeation resistance plus tensile strength, low compression set, and other mechanical characteristics, ozone resistance, and interlayer adhesion.

Abstract: A rubber composition, including ?,?-ethylenically unsaturated nitrile-conjugated diene copolymer rubber (A) having number average molecular weight of 50,000 to 150,000, ?,?-ethylenically unsaturated nitrile-conjugated diene copolymer rubber (B) having number average molecular weight of 1,000 to 20,000, ethylene-?-olefin copolymer rubber (C), and a graft copolymer (D); wherein said graft copolymer (D) is obtained by performing graft copolymerization on a mixture of an aromatic vinyl compound and an ?,?-ethylenically unsaturated nitrile monomer with an ethylene-propylene-unconjugated copolymer, and a content of structure units of said ethylene-propylene-unconjugated copolymer is 20 to 70 wt %; a ratio of the graft copolymer (D) with respect to 100 parts by weight in total of said rubber (A), rubber (B) and rubber (C) is 1 to 30 parts by weight; and a composition ratio of the rubber (A), rubber (B) and rubber (C) is rubber (A): 20 to 79 wt %, rubber (B): 1 to 30 wt %, and rubber (C): 20 to 50 wt %, is subjected

Abstract: A rubber composition includes ?,?-ethylenically unsaturated nitrile-conjugated diene copolymer rubber (A), ?,?-ethylenically unsaturated nitrile-conjugated diene copolymer rubber (B), ethylene-?-olefin copolymer rubber (C), and a graft copolymer (D). The graft copolymer (D) is obtained by performing graft copolymerization on a mixture of an aromatic vinyl compound and an ?,?-ethylenically unsaturated nitrite monomer with an ethylene-propylene-unconjugated copolymer. A content of structure units of the ethylene-propylene-unconjugated copolymer is 20 to 70 wt %, a ratio of the graft copolymer (D) with respect to 100 parts by weight in total of said rubber (A), rubber (B) and rubber (C) is 1 to 30 parts by weight. A composition ratio of the rubber (A), rubber (B) and rubber (C) is rubber (A): 20 to 79 wt %, rubber (B): 1 to 30 wt %, and rubber (C): 20 to 50 wt %.

Abstract: A cross-linkable rubber composition comprised of a mixture of a carboxyl group-containing nitrile copolymer rubber (A) with a carboxyl group content per 100 g of 2×10?3 to 1×10?1 equivalents and a carboxyl group-containing acryl-based polymer (B) with a carboxyl group content per 100 g of 4×10?4 to 1×10?1 equivalents in a weight ratio A:B=40:60 to 90:10 into which a cross-linking agent (C) able to cross-link the carboxyl groups of both the nitrile copolymer rubber (A) and the acryl-based polymer (B) is blended, the amount blended of the cross-linking agent (C), converted to equivalents of functional groups able to react with carboxyl groups in the cross-linking agent, being 0.3 to 3 times equivalents of the total content of both the carboxyl groups of the nitrile copolymer rubber (A) and the acryl-based polymer (B) is used.

Abstract: A rubber composition, including &agr;,&bgr;-ethylenically unsaturated nitrile-conjugated diene copolymer rubber (A) having number average molecular weight of 50,000 to 150,000, &agr;,&bgr;-ethylenically unsaturated nitrile-conjugated diene copolymer rubber (B) having number average molecular weight of 1,000 to 20,000, ethylene-&agr;-olefin copolymer rubber (C), and a graft copolymer (D); wherein said graft copolymer (D) is obtained by performing graft copolymerization on a mixture of an aromatic vinyl compound and an &agr;,&bgr;-ethylenically unsaturated nitrile monomer with an ethylene-propylene-unconjugated copolymer, and a content of structure units of said ethylene-propylene-unconjugated copolymer is 20 to 70 wt % ; a ratio of the graft copolymer (D) with respect to 100 parts by weight in total of said rubber (A), rubber (B) and rubber (C) is 1 to 30 parts by weight; and a composition ratio of the rubber (A), rubber (B) and rubber (C) is rubber (A): 20 to 79 wt %, rubber (B) 1 to 30 wt %, and rubber (C):