Patent GB-867800-A (GB)
Title: High detergency automotive engine lubricant
IPC: C10M169/00
Filed: 1959-06-02
Abstract: A mineral oil or synthetic ester oil composition contains (A) an oil-soluble metal-containing neutralized phosphosulphurized hydrocarbon containing 0.5-4.5% wt. phosphorus and 4-8% wt. sulphur, the atomic ratio of metal to phosphorus therein being from 1 to 5 and (B) an oil-soluble multifunctional copolymer derived from an oxygen- or nitrogen-containing polar C4-C50 monomer and at least one other ethylenically unsaturated monomer, the copolymer having a molecular weight in the range of 5,000-200,000 and the proportion of (B) being from 0.2 to 3 parts by weight per part by weight of (A).  Ingredient (A) is the neutral reaction product of an oil-soluble phosphosulphurized hydrocarbon with an oil-soluble neutralizing agent prepared by reacting an excess of an inorganic alkaline earth base with an alkyl phenol, alkyl phenol sulphide, sulphonic acid or metal salt thereof.  The oil base of the composition may be a mineral lubricating oil, a synthetic ester lubricating oil, a heating oil, a fuel oil or a jet fuel and the composition may be, for example, an internal combustion engine lubricant, a gear lubricant or an automatic transmission fluid.  The mixture of ingredients (A) and (B) acts as a detergent and also imparts oxidation resistance to the composition.  Ingredient (B) may be a copolymer of (a) N-vinyl butyrolactam or a substitution derivative thereof and (b) a C4-C40 ethylenically unsaturated ester, an olefin, styrene or a substituted styrene, a vinyl ether or an unsaturated carboxylic acid.  The unsaturated ester mentioned under (b) may be an ester of acrylic, methacrylic, maleic or fumaric acid and such ester may be copolymerized with the N-vinyl butyrolactam and also with vinyl acetate.  The oil composition may also contain polyether alcohols (e.g. diethylene glycol mono-ethyl ether), zinc dialkyldithiophosphates, phosphosulphurized terpenes, phenyl alpha-naphthylamine, polymeric methacrylates, fumarates or maleates, polyisobutylene, or wax-naphthalene condensates.  In the examples, mineral lubricating oil compositions are described in which ingredient (A) is P2S5-treated polybutene which has been neutralized either with highly basic barium alkyl aromatic sulphonate or with a CO2-treated barium salt of an alkyl phenol sulphide, and in which ingredient (B) is dilaurylfumarate / vinylacetate/N-vinyl-2-pyrrolidone copolymer, "Acryloid 966" (a copolymer of C4-C16 methacrylates with a nitrogen-containing monomer), dioctadecyl fumarate/diethyl fumarate/vinyl butyrate/N-vinyl caprolactam copolymer, dicetyl fumarate/methyl methacrylate/N-vinyl butyrolactam copolymer, technical lauryl methacrylate / beta - diethylaminoethyl methacrylate/styrene copolymer, decyl methacrylate/4-vinyl pyridine/vinyl amyl ether copolymer or diethylaminoethyl methacrylate/mixed C4-C16 methacrylates copolymer.  In further examples, (i) an aircraft fuel is described consisting of JP-5 oil, P2S5-treated polybutene neutralized with highly basic barium alkyl aromatic sulphonate, and technical lauryl methacrylate/beta-diethylaminoethyl methacrylate/styrene copolymer and (ii) an aviation engine lubricating oil is described consisting of di-2-ethylhexyl sebacate, a complex ester (derived from polyethylene glycol 200, sebacic acid and 2-ethylhexyl alcohol), P2S5-treated petroleum residuum neutralized with CO2-treated barium alkyl phenate, maleic anhydride/C8 oxoalkyl fumarates/vinyl acetate copolymer, tricresyl phosphate, phenothiazine and a silicone.