GB947585A - Artificial leathers and foils provided with an adhesive layer - Google Patents

Abstract

A sheet structure, e.g. artificial leather or foil, consists essentially of a halogenous synthetic rubber carrier layer provided wholly or in part with at least one adhesive layer, wherein the halogenous synthetic rubber has been vulcanized by means of a compound (A) which contains at least two -N=C< groups which are not part of a ring and/or a N,N1-dimethylol compound (B), general formulae of which are given, at a temperature below 150 DEG C. and which contains only few or no crystalline fractions but contains those fractions of the compounds (A) and/or (B) which are not used up by the vulcanization and wherein the adhesive layer consists essentially of poly-2-chlorobutadiene and contains relatively large quantities of crystalline fractions. The halogenous synthetic rubber may have been vulcanized in the presence of compound (A) and/or compound (B), to the extent of 0,1 - 12% by weight, preferably 1,0-7% by weight, based on the weight of halogenous synthetic rubber, and of 0,1-6%, advantageously 0,3-4% by weight of a diisocyanate and/or polyisocyanate (C). The poly-2-chlorobutadiene of the adhesive coating may contain 35-100% by weight of crystalline fractions. The halogenous synthetic rubber may have been vulcanized at a temperature which is at least 10 degrees below the decomposition temperature of the substances (A), (B) and (C). The compound (A) may be a reaction product of a diamine or polyamine with an aldehyde or a ketone, e.g. cyclohexanone, acetophenone, methyl ethyl ketone, ethyl amyl ketone, acetylacetone, acetone - dicarboxylic acid - dimethyl ester, acetoacetic ester and aldehyde, benzaldehyde, acrolein, glyoxal, crotonaldehyde, and furfural. The amine may contain two terminal primary amino groups and may have a carbon chain containing fewer than 19 carbon atoms, e.g. ethylene, propylene, butylene, and hexamethylene diamine, diethylene and dipropylene triamine, and tetramethylene pentamine, or mixtures thereof. The compound (A) may be a reaction product of a dinitroso and/or polynitroso compound with a compound which contains at least one methylene group with active hydrogen, e.g. acetyl acetone, acetoacetic and malonic ester. The halogenous synthetic rubber may contain up to 200% by weight of fillers and/or dyestuffs, e.g. carbon black, metal or metalloid oxides or silicates, textile, asbestos or glass fibres. Sulphur and/or organic sulphur compounds may be additionally used as well as the compounds (A), (B) and (C) in the vulcanization of the halogenous synthetic rubber, examples of such compounds being thiuram sulphide, disulphide and tetrasulphide; dithiocarbamates generally, e.g. ethyl phenyl dithiocarbamate, zinc dimethyl dithiocarbamate, N-cyclohexyl ethyl ammonium cyclohexyl ethyl dithiocarbamate, N-pentamethylene ammonium pentamethylene dithiocarbamate, and xanthates. The sheet structures may be laminated to each other and to textile fabric by the application of heat. Examples of isocyanates are hexamethylene and toluidine diisocyanate, triphenyl methane triisocyanate and methylene bis (4-phenyl isocyanate).