Patent GB-775089-A (GB)
Title: Improvements in corrosion-proof high pressure lubricants
Filed: 1953-10-23
Abstract: A lubricating composition suitable for use at high pressures and for running-in purposes, especially as a gear lubricant, comprises an oleaginous material, 1-8 per cent of a lubricity improver as defined below, 0.05-1 per cent of an organic nitro compound, 0.2-2 per cent of a reaction product (having a molecular weight of 750-1500) of an alcohol with an alkylene oxide and 0.1-2 per cent of an anticorrosive agent as defined below, percentages being by weight.  Suitable oleaginous materials are mineral lubricating oils, synthetic lubricating oils (e.g. polymerized olefins, alkylated aromatic hydrocarbons and esters of dicarboxylic acids with aliphatic alcohols) and natural or synthetic glyceride fats.  The lubricity improver consists of at least one oil-soluble compound chosen from the multisulphides of xanthates according to Specification 745,409, organic sulphides according to Specification 748,404, sulphurized aromatic-substituted olefines according to Specification 744,477, sulphurized synthetic esters of unsaturated carboxylic acids according to Specification 744,761, and sulphurized unsaturated alcohols according to Specification 744,762.  The organic nitro compounds, which are activators increasing the action of the lubricating improvers, may be chosen from nitroparaffins, m - dinitrobenzene, 4 - brom - 1 . 3 - dinitrobenzene, 4 - chlor - 1 . 3 - dinitrobenzene, 2 . 4 - dinitrophenol, 6 - chlor - 1 . 3 - dinitrophenol, and their C-alkyl derivatives or mixtures of these. The alcohol - alkylene oxide reaction products, which are solventaids increasing the solubility of the organic nitro compounds in the oleaginous base, may be produced by reacting ethylene, propylene or butylene oxide, or mixtures of these, with aliphatic, cycloaliphatic, aromatic or araliphatic alcohols, but particularly with ethyl - 1 . 3 - hexanediol, 2 - methyl - pentanediol - 1, 4, 2 - ethylhexanol or lauryl alcohol.  The anticorrosive agent is a compound having hydroxyl groups located on different carbon atoms, which are preferably linked together through an ether oxygen, one of the hydroxyl groups being esterified with a higher fatty acid containing about 18 carbon atoms.  Suitable anticorrosive agents are the mono-oleates and monostearates of di- or tri-ethylene gylcol, propylene glycol, di- or tripropylene glycol, glycerine, diglycerine, sorbitol, sorbitan; hexane-triol or pentaerythritol, or mixtures of these. The lubricating composition may contain additional ingredients such as viscosity improvers, setting point depressants, froth inhibitors and antioxidants.  In the examples mineral lubricating oil compositions are described containing (1) dibutylxanthic acid disulphide, 2 . 4 - dinitrophenol monoethylhexylether of a polypropylene glycol, diethylene glycol mono-oleate and 1 . 2 - propylene glycol mono-oleate, (2) dibutylxanthic acid disulphide, 6 - chlor - 2 . 4 - dinitrophenol, monolauryl ether of a polypropylene glycol and sorbitol monooleate, (3) dibutylxanthic acid disulphide, 6 - brom - 2 . 4 - dinitrophenol, mono-octyl ether of a polypropylene glycol and diglycerine mono-oleate, (4) diethylhexylxanthic acid disulphide, 2 . 4 - dinitrophenol, 2 - ethylhexanol - ethyleneoxide - propylene oxide reaction product and sorbitol mono-oleate, (5) dipropylxanthic acid disulphide, 2 . 4 - dinitroanisole, lauryl alcohol - ethylene oxide - propylene oxide reaction product and diglycerine monooleate, (6) dibenzyl disulphide, 2 . 4 - dinitroanisole, monoethylhexyl ether of a polypropylene glycol and diglycerine monooleate and (7) dibenzyl disulphide, 2 . 4 - dinitrophenol, monolauryl ether of a polypropylene glycol and hexanetriol monooleate.