Patent GB-880991-A (GB)
Title: Lubricating compositions
IPC: C10M169/00
Filed: 1959-09-29
Abstract: An extreme pressure lubricant comprises an oleaginous base together with (1) pentachlorobenzenethiol, (2) a heavy metal salt of pentachlorobenzenethiol (partially substituted, if desired, by other anions), (3) pentachlorophenylmercaptoacetic acid (further substituted on the alpha atom of the acetic acid, if desired, by a C1 - C4 alkyl group), (4) a heavy metal salt of pentachlorophenylmercaptoacetic acid (partially substituted, if desired, by other anions) or (5) an ester of pentachlorophenylmercaptoacetic acid.  The oleaginous base may be a mineral oil, a fatty oil (e.g. an animal, vegetable or marine oil) or a synthetic oil, or mixtures of these.  Synthetic oils mentioned are silicone oils (including those with halogen or hydroxyl substituents), diesters of dicarboxylic acids (including alkyl and cycloalkyl esters of alkylene dicarboxylic acids, phthalic acid, thiodipropionic acid and oxydipropionic acid), fatty acid esters of polyhydric alcohols (e.g. ethylene glycol, propylene glycol, diethylene glycol or pentaerythritol), complex esters, polymers of unsaturated hydrocarbons, alkylene oxide polymers (including propylene oxide-tetrahydrofuran copolymers and polyaryl ethers), silones, organosilicates, disiloxanes, fluorocarbon oils, tetrasubstituted ureas and trioctyl phosphate. In the case of additives (2) and (4), the additional anions which may be present satisfy some of the valences of the metal; such anions include halide, hydroxide, carbonate, bicarbonate and sulphate ions. Additives (5) may be alkyl, cycloalkyl, aryl, alkaryl or aralkyl esters and the esterifying hydrocarbon radical may carry substituents such as halogen atoms or hydroxy, carboxy, sulphonic acid, alkoxy, hydroxyalkoxy, aryloxy, cycloalkoxy, sulphamoyl, mercapto or acyl radicals.  The lubricant may be thickened to a grease structure by the addition of alkali metal soaps of fatty or naphthenic acids, soap-salt complexes, silica aerogels (which may have been treated with organic silicon compounds), organic derivatives of bentonite clay, ureides (which may be formed by reaction between an amine and an isocyanate; this reaction may be carried out in situ in the lubricating oil), urethanes, allophanates, carbazides, carbazones, phthalimides, phthalocyamines, or indanthrene.  Other ingredients which may be present in the lubricant are antioxidants (e.g. alkyl phenols, aminophenols, aromatic amines, iron octoate and phenothiazine) pour point depressants, viscosity improvers and antifoaming agents.  In the examples, lubricants are described in which the base oil is polymethylphenyl silicone (which may be chlorinated), a polyester (believed to be pentaerythritol tetrapelorgonate), didodecyl dioctyl silane, didodecyl diphenyl silane, octadecyl tridecyl silane or hexa (2-ethyl-hexoxy) disiloxane and the additive is pentachlorobenzenethiol, zinc pentochlorobenzenethiolate or pentachlorophenylmercaptoacetic acid. In further examples, lubricating greases are described in which the base oil is polymethylphenyl silicone (chlorinated or not) and/or the above-mentioned polyester, or is mineral oil, the thickener is silica, lithium hydroxystearate or an ureide (formed by reacting, in situ in the oil base, ditolylene di-isocyanate with p-chloroaniline and p-toluidine) and the additive is pentactilorobenzenethiol (or its zinc, lead or cadmium salt), or pentachlorophenylmercaptoacetic acid (or its zinc, lead or cadmium salt, or its methyl, isopropyl, 2-ethylbutyl or 4-chloro-1-butyl ester).ALSO:Additives for lubricating oil compositions (see Group III) include metal salts of pentachlorobenzenethiol or of pentachlorophenylmercaptoacetic acid and esters of pentachlorophenylmercaptoacetic acid.  In examples, the conversion of sodium pentachlorobenzenethiolate or sodium pentachlorophenylmercaptoacetate to the corresponding zinc, cadimum or lead salt is described.  In further examples, the esterification of pentachlorophenylmercaptoacetic acid by refluxing with alcohol in the presence of p-toluene sulphonic acid is described.  Alcohols mentioned are methanol, ethanol, isopropanol, 2 - ethylbutanol, 2 - ethyhexanol, 4 - chloro 1 - butanol and ethylene glycol (to produce the mono-ester).