Patent ID: 8398087
Filing Date: 2013-03-19
Classification: C08K,C08L,F16D,F16J,Y10T

Abstract:
1. A bonded piston seal, which comprises: a metal ring; and an acrylic rubber copolymer comprising at least one of i) an alkyl acrylate having an alkyl group of 1-8 carbon atoms; and ii) an alkoxyalkyl acrylate having an alkoxyalkylene group of 2-8 carbon atoms as a major component, and 0.1 to 10 Wt. % of a vulcanizable group-containing monomer consisting of at least one of (a) reactive halogen-containing vinyl monomer, (b) epoxy group-containing vinyl monomer, (c) carboxyl group-containing vinyl monomer, (d) hydroxyl group-containing vinyl monomer, and (e) amido group-containing vinyl monomer, said acrylic rubber copolymer being vulcanization-bonded to the metal ring except the sliding site along which a mating seal member slides, where the acrylic rubber seal is partially bonded to the metal ring through an adhesive layers, wherein the adhesive layers comprise (a) an underlayer adhesive layer comprising a phenol resin and an epoxy resin, and (b) an overlayer adhesive layer comprising a phenol resin, a halogenated polymer, and a metal oxide, the overlayer adhesive layer being formed from a vulcanizable adhesive composition having a solid matters composition comprising 45-75 wt. % of phenol resin, 5-25 wt. % of halogenated polymer, and 10-30 wt. % of metal oxide on the basis of all the solid matters, wherein the phenol resin is a mixture comprising 50-90% by weight of novolak type phenol resin and 50-10% by weight of resol type phenol resin, on the basis of the phenol resin mixture.