Patent GB-372776-A (GB)
Title: Improvements in or relating to the production of compositions of or containing rubber
IPC: C08J3/09
Filed: 1931-02-11
Abstract: A rubber or like composition, suitable as an adhesive for rubber, textiles or leather, is prepared by adding to an aqueous dispersion of rubber, vulcanized rubber, waste or reclaim rubber, guttapercha, balata or the like, or synthetic rubber (including natural latices), a rubber solvent, such as coal-tar naphtha, as such, or as an aqueous dispersion, or in both forms, and treating the mixture with a precipitating agent such as methyl, ethyl or propyl alcohol, acetone or mixtures thereof with one another or with other liquids such as ether, petroleum or coal-tar naphtha, benzene or carbon tetrachloride, to produce a dispersion in which the water is the disperse phase.  A precipitating agent having a delayed action or becoming active only on heating, for example salts of hydrofluosilicic acid may alternatively or in addition be employed. The initial rubber dispersion may contain compounding or vulcanizing ingredients such as whiting, carbon black, leather-jute- or asbestos-fibre, wood pulp or flour, cotton flock, abrasives, rubber crumb, or cork, and may be in concentrated form as described in Specifications 219,635 and 290,313, [both in Class 70, Indiarubber &c.].  Rubber latex may be frothed before or during use.  In an example 600 parts of frothed 60 per cent rubber latex containing 1 part of ammonium oleate are poured slowly with agitation into 100 parts of coal-tar naphtha, and 300 parts of a mixture of equal parts of methylated spirits and coal-tar naphtha added slowly; a phase reversal takes place with increase in viscosity.  The coal-tar naphtha first added may be in the form of an aqueous dispersion comprising 80 per cent naphtha, 0,5 per cent of each of gelatine oleic acid and ammonia, and 18,5 per cent of water.  Coal-tar naphtha of boiling-point 130-160 DEG  C. may be employed as the rubber solvent in dispersed or undispersed form; lower-boiling naphtha must be employed as a dispersion.ALSO:A rubber or like composition, suitable as an adhesive for rubber, textiles or leather, is prepared by adding to an aqueous dispersion of rubber, vulcanized rubber, waste or reclaim rubber, gutta-percha, balata or the like, or synthetic rubber (including natural latices) a rubber solvent, such as coal-tar naphtha, as such or as an aqueous dispersion, or in both forms, and treating the mixture with a precipitating agent such as methyl, ethyl, or propyl alcohol, acetone or mixtures thereof with one another or with other liquids such as ether, petroleum or coal-tar naphtha, benzene or carbon tetrachloride, to produce a dispersion in which the water is the disperse phase.  A precipitating agent having a delayed action or becoming active only on heating, for example, salts of hydrofluosilicic acid may alternatively or in addition be employed.  The initial rubber dispersion may contain compounding or vulcanizing ingredients such as whiting, carbon black, leather-jute or asbestos-fibre, wood pulp or flour, cotton flock, abrasives, rubber crumb, or cork, and may be in concentrated form as described in Specifications 219,635 and 290,313, [both in Class 70, Indiarubber &c.].  Rubber latex may be frothed before or during use. In an example 100 parts of frothed 60 per cent rubber latex containing 1 part of ammonium oleate are poured slowly with agitation into 600 parts of coal-tar naphtha and 300 parts of a mixture of equal parts of methylated spirits and coal-tar naphtha added slowly; a phase reversal takes place with increase in viscosity.  The coal-tar naphtha first added may be in the form of an aqueous dispersion comprising 80 per cent naphtha, 0,5 per cent of each of gelatine oleic acid and ammonia, and 18,5 per cent of water. Coal-tar naphtha of boiling point 130-160 DEG  C. may be employed as the rubber solvent in dispersed or undispersed form; lower boiling naphtha must be employed as a dispersion.