Abstract: A refrigerant transporting rubber hose which is capable of reducing the refrigerant permeation amount to a higher extent than earlier while maintaining the practicability of its extruded skin surface and without increasing the volume of the hose nor sacrificing mandrel removability. The hose is of a layered structure at least comprising an inner layer and an outer layer, wherein an inner layer material forming the inner layer contains 60-200 parts by weight of a scale-shape filler and 10-100 parts by weight of carbon black per 100 parts by weight of a rubber material having as small a permeation coefficient against a refrigerant to be transported as possible.

Abstract: Crystalline N-methoxymethylated nylon is useful to form a coating on a rubber substrate. It is prepared by adding acid to N-methoxymethylated nylon and heat treating the mixture for crystallization.

Abstract: A process for producing a tubular rubber product such as a rubber hose and a rubber coupling in which a polyamide resin and/or polyester resin layer is formed to the main body of a tubular rubber product. The resin layer is formed either by coating an organic solvent-soluble nylon to the surface of the main body of the tubular rubber product applied with the surface treatment of a halogenoid compound, or by polyamide resin or polyester resin film having a softening point in the vulcanization temperature region and treated with an adhesive mainly comprising a resorcine-formaldehyde resin and a rubber latex or treated with an adhesive rubber mainly comprising a resorcine, a formaldehyde-forming substance and a vinylpyridine-butadiene-styrene copolymer rubber and then bonding under vulcanization onto the main body of the non-vulcanized tubular rubber product.

Abstract: A process for producing a tubular rubber product such as a rubber hose and a rubber coupling in which a polyamide resin and/or polyester resin layer is formed to the main body of a tubular rubber product. The resin layer is formed either by coating an organic solvent-soluble nylon to the surface of the main body of the tubular rubber product applied with the surface treatment of a halogenoid compound, or by polyamide resin or by polyester resin film having a softening point in the vulcanization temperature region and treated with an adhesive mainly comprising a resorcine-formaldehyde resin and a rubber latex or treated with an adhesive rubber mainly comprising a resorcine, a formaldehyde-forming substance and a vinylpyridine-butadiene-styrene copolymer rubber and then bonding under vulcanization onto the main body of the non-vulcanized tubular rubber product.