Patent GB-801151-A (GB)
Title: Gear lubricant improving agents
IPC: C07F9/02
Filed: 1956-01-19
Abstract: A composition, suitable for addition to lubricating oil to produce a gear lubricant effective under extreme pressures, comprises (a) an oil-soluble phosphorodithioic acid triester metal salt of a phosphorodithioic acid diester bis-phosphorodiethioic acid tetraester or phosphorodithioic acid diester thioanhydride, and (b) an oil-soluble turpentine or di-(aralkyl) polysulphide having at least one sulphur atom bonded only to one or more sulphur atoms in the polysulphide molecule, the proportions of ingredients (a) and (b) being such that, when the composition is dissolved in a solvent therefor in an amount equal to 3.5-15 per cent, based on the weight of the total solution, this solution will have contributed thereto by these ingredients 0.20-0.75 per cent of phosphorus and 0.25-1 per cent of sulphur bonded as described above.  The lubricating oil, to which the composition may be added, may be of animal, vegetable, mineral or synthetic origin.  Ingredient (a) has the formula <FORM:0801151/III/1> wherein R1 and R2 are the same or different organic radicles and X is an organic radicle or the hydrogen equivalent of a metal atom.  R1 and R2 may be hydrocarbon radicles or they may bear such substituents as halogen atoms or nitro, alkoxy, thioalkoxy or carboalkoxy groups.  X may be hydrocarbon radicle bearing a substituent containing at least one of oxygen, sulphur, phosphorus, halogen, nitrogen and metal, for example, a hydroxy, mercapto, nitro, cyano or carboxy substituent.  The aralkyl radicles of ingredient (b) may carry substituents such as halogen or alkoxy, carboalkoxy, nitro, nitroso or hydroxyl groups.  The composition, or lubricants prepared from it, may contain additional ingredients such as rust inhibitors (e.g. basic metal petroleum sulphonates, metal phenolates, amines and benzyl thiocyanate), oiliness agents (e.g. olein, methyl oleate, oleic acid and sulphurized or unsulphurized sperm or corn oil), viscosity index improvers (e.g. alkyl methacrylate polymers and polymerized butylene), detergents (e.g. metal salts of naphthenic, fatty or petroleum sulphonic acids), film strength improving agents (e.g. chlorinated paraffin wax, chlorinated eicosane, hexachloro diphenylether and polychloro biphenyl), pour point depressors (e.g. wax-alkylated naphthalene or phenanthrene), foam inhibitors (e.g. silicones), oxidation inhibitors and odour improvers.  In the examples, compositions added to mineral lubricating oil have ingredients (a) chosen from zinc salts of a mixture of o,o-di-isopropylphosphorodithioic acid and o,o - di - (4 - methyl - 2 - pentyl)phosphorodithioic acid, zinc o,o-di-(4-methyl-2-pentyl) phosphorodithioate, o,o - di - (4 - methyl-2 - pentyl) - 2 - hydroxyethyl or hydroxypropyl phosphorodithioate and bis-[o,o-di-(4-methyl - 2 - pentyl) phosphorodithioate] and ingredients (b) chosen from monochlor dibenzyl tetrasulphide, dibenzyl polysulphides, turpentine polysulphides and di-phenethyl tetrasulphide.  Additional ingredients present in some compositions are chosen from lead naphthenate, chlorinated cicosane, sulphurized sperm oil and basic calcium petroleum sulphonate.