GB196924A - - Google Patents

Abstract

196,924. Russell, W. F. April 26, 1922, [Convention date]. Vulcanizing-compositions.-The vulcanization of rubber mixture containing sulphur and a metallic oxide, such as zinc, lead, aluminium, or manganese oxide, is improved by the addition of certain substances which promote the dissolution of the oxide in the rubber. These substances are carboxylic or resin acids whose salts with the metallic oxide used are soluble in hot aromatic hydrocarbons, such as benzene or xylene, or in terpene hydrocarbons, such as pinene or dipentene, either alone or in the presence of organic bases, such as pyridene or piperidine. Examples of such acids are the monobasic saturated and unsaturated fatty acids, particularly the higher members such as lauric, palmitic, stearic, oleic, and linoleic acids; aryl derivatives of fatty acids, such as phenylacetic, phenylpropionic, and cinnamic acids; aromatic monobasic acids, such as benzoic and toluic acids; certain derivatives of aromatic monobasic acids, such as the alkoxybenzoic acids, e.g. anisic acid; and acid resinous substances, such as colophony, Burgundy pitch, and Venice turpentine. Derivatives of these acids such as their salts of zinc, ammonia, or organic bases or their double salts of zinc and ammonia or an organic base, may also be used, and if the zinc salts be employed the zinc oxide may be omitted from the mix. The action of the acids is usually enhanced by the presence of organic basic or base-generating substances, such as the usual accelerators, particularly urea. The substances may be added to the rubber either on the mill with the other compounding ingredients, or during the crÛpeing or sheeting operation, or they may be mixed with the latex before coagulation either in the free state or in the form of glycerides which are decomposed by enzymes in the latex. Specification 4263/14 is referred to. The Specification as open to inspection under Sect. 91 (3) (a) comprises the use of any substance which will promote the dissolution of the metallic oxide in the rubber. This subjectmatter does not appear in the Specification as accepted.