Tokai Rubber Industries, Ltd.

Kazuhiko Nishimura

Ichiro Igarashi

Hiroaki Ito

A laminated rubber structure having a first layer formed of a first rubber composition including a copolymer of tetrafluoroethylene, vinylidene fluoride, and hexafluoropropylene, the copolymer having at least one peroxide-crosslinking peroxide unit each bonded to a corresponding one of at least one end thereof, and containing 10 to 50 mole % of the vinylidene fluoride; and a second layer formed of a second rubber composition which includes an acrylonitrile-butadiene rubber containing 25 to 45 weight % of acrylonitrile, and a bifunctional crosslinking aid, the second layer contacting the first layer, the first and second layers being chemically bonded to each other by crosslinking caused between the copolymer and the acrylonitrile-butadiene rubber owing to the peroxide-crosslinking unit.

Laminated rubber structure

A rubber hose having an outer tube formed of a rubber material, and an inner tube located radially inwardly of the outer tube, the inner tube including an inner layer formed of a first composition containing a fluoro rubber as a major constituent thereof, and an outer layer located radially outwardly of the inner layer, the outer layer of the inner tube being formed of a second composition containing as a major constituent thereof a blend of chlorosulphonated polyethylene and polyvinyl chloride.

Rubber hose

A rubber hose having an outer rubber tube and an inner rubber tube located radially inwardly of the outer rubber tube, the inner rubber tube including an inner layer and an outer layer located between the inner layer and the outer rubber tube, the inner layer being formed of a first polymer blend of acrylic rubber and fluorine-contained resin, the outer layer being formed of a second polymer blend which is different from the first polymer blend and which contains epichlorohydrin rubber. The rubber hose may further have a reinforcing fiber layer disposed between the outer rubber tube and the outer layer of the inner rubber tube such that the inner and outer rubber tubes and the fiber layer constitute an integral tubular body.

In rubber hoses for conveying fuels, the inner tube rubber layer coming into contact with fuels generally comprises two sublayers, namely the inside fluororubber layer coming into direct contact with fuels and the outside layer of an NBR and the like. The fluororubber layer is undesirably subject to degradation due to amine type additives contained in fuels and is poor in adhesion to the outside layer. In accordance with the invention, the contents of vinylidene fluoride, one of the fluororubber constituents, is reduced to 10-50 mole percent and at the same time a monomer capable of causing crosslinking of the fluororubber in the presence of a peroxide is newly added as a component of the fluororubber composition in a specified amount. The results are prevention of the degradation due to amine type additives and improved adhesion to the outside layer.

Growing community of inventors

Kasugai, Japan

Kazuhiko Nishimura