Abstract: A trunk piston marine engine lubricating oil composition for a medium-speed compression-ignited marine engine comprises, in a major amount, an oil of lubricating viscosity containing 50 mass % or more of a Group II basestock, and, in respective minor amounts, (A) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent having a basicity index of 4.5 or less, and (B) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent having a basicity index of greater than 4.5. The ratio of detergent (A) to detergent (B), both expressed as mass of active ingredient, is in the range from 0.5 to 15. The trunk piston marine engine lubricating oil composition has a TBN (using ASTM D2896) of 20 to 60.

Abstract: A lubricating oil composition having a total base number of more than 15 mg KOH/g, as determined by ASTM D2896, and including at least 40 mass % of an oil of lubricating viscosity; at least one detergent; and at least one compound of the formula (II): In formula (II), each Ar independently represents an aromatic moiety having 0 to 3 substituents selected from the group consisting of alkyl, alkoxy, alkoxyalkyl, hydroxy, hydroxyalkyl, acyloxy, acyloxyalkyl, aryloxy, aryloxy alkyl, halo and combinations thereof; each L is independently a linking moiety comprising a carbon-carbon single bond or a linking group; each Y? is independently a moiety of the formula Z(O(CR2)n)yX—, wherein X is selected from the group consisting of (CR?2)z, O and S; R and R? are each independently selected from H, C1 to C6 alkyl and aryl; z is 1 to 10; n is 0 to 10 when X is (CR?2)z, and 2 to 10 when X is O or S; y is 1 to 30; Z is H, an acyl group, an alkyl group or an aryl group; each a is independently 0 to 3, with the proviso tha

Abstract: A trunk piston marine engine lubricating oil composition for a medium-speed compression-ignited marine engine comprises, in a major amount, an oil of lubricating viscosity containing 50 mass % or more of a Group II basestock. and, in respective minor amounts, (A) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent having a basicity index of 4.5 or less, and (B) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent having a basicity index of greater than 4.5. The ratio of deterrent (A) to detergent (B), both expressed as mass of active ingredient, is in the range from 0.5 to 15. The trunk piston marine engine lubricating oil composition has a TBN (using ASTM D2896) of 20 to 60.

Abstract: A lubricating oil composition including at least one sulphurized overbased metal phenate detergent prepared from a C9-C15 alkyl phenol, at least one sulphurizing agent, at least one metal and at least one overbasing agent. The detergent includes less than 6.0% by combined mass of unsulphurized C9-C15 alkyl phenol and its unsulphurized metal salt. The lubricating oil composition exhibits an improved rate of acid neutralization.

Abstract: A lubricating oil composition having a total base number of more than 15 mg KOH/g, as determined by ASTM D2896, and including at least 40 mass % of an oil of lubricating viscosity; at least one detergent; and at least one compound of the formula (II): In formula (II), each Ar independently represents an aromatic moiety having 0 to 3 substituents selected from the group consisting of alkyl, alkoxy, alkoxyalkyl, hydroxy, hydroxyalkyl, acyloxy, acyloxyalkyl, aryloxy, aryloxy alkyl, halo and combinations thereof; each L is independently a linking moiety comprising a carbon-carbon single bond or a linking group; each Y? is independently a moiety of the formula Z(O(CR2)n)yX—, wherein X is selected from the group consisting of (CR?2)z, O and S; R and R? are each independently selected from H, C1 to C6 alkyl and aryl; z is 1 to 10; n is 0 to 10 when X is (CR?2)z, and 2 to 10 when X is O or S; y is 1 to 30; Z is H, an acyl group, an alkyl group or an aryl group; each a is independently 0 to 3, with the proviso tha

Abstract: The residual chlorine content of a polyolefin-substituted carboxylic acylating agent formed by a chlorine-assisted reaction of a polyolefin and an &agr;,&bgr;-unsaturated carboxylic reactant can be reduced by heating the polyolefin-substituted carboxylic acylating agent having a residual chlorine content in the presence of an &agr;,&bgr;-unsaturated carboxylic reactant, optionally in the further presence of a sulfonic acid. Residual chlorine content can be further reduced by using, in the reaction of the polyolefin &agr;,&bgr;-unsaturated carboxylic reactant, a high speed mixer provided with a dual pitch blade.

Abstract: The residual chlorine content of a polyolefin-substituted carboxylic acylating agent formed by a chlorine-assisted reaction of a polyolefin and an &agr;, &bgr;-unsaturated carboxylic reactant can be reduced by heating the polyolefin-substituted carboxylic acylating agent having a residual chlorine content in the presence of an &agr;, &bgr;-unsaturated carboxylic reactant, optionally in the further presence of a sulfonic acid. Residual chlorine content can be further reduced by using, in the reaction of the polyolefin &agr;, &bgr;-unsaturated carboxylic reactant, a high speed mixer provided with a dual pitch blade.

Abstract: A low-sediment, low-tar, chlorine-free thermal process for preparing oil-soluble polyalkenyl derivatives of monounsaturated C.sub.3 -C.sub.10 monocarboxylic acid producing compounds and monounsaturated C.sub.4 -C.sub.10 dicarboxylic acid producing compounds is disclosed. The process involves reacting the mono- or dicarboxylic acid producing compound with a polyalkene at high temperature and under high inert gas partial pressure in the presence of a sediment-inhibiting amount of hydrocarbyl substituted sulfonic acid. The polyalkenyl derivatives are useful per se as additives in lubricating oils, functional fluids, and fuels and are also useful as intermediates in the preparation of other products (e.g., succinimides) useful as additives in lubricating oils, functional fluids, and fuels.

Abstract: A low-sediment, low-tar, chlorine-free thermal process for preparing oil-soluble polyalkenyl derivatives of monounsaturated C.sub.4 -C.sub.10 dicarboxylic acid producing compounds is disclosed. The process involves reacting the dicarboxylic acid producing compound with a polyalkene at high temperature and under high inert gas partial pressure in the presence of a sediment-inhibiting amount of hydrocarbyl substituted sulfonic acid. The polyalkenyl derivatives are useful per se as additives in lubricating oils, functional fluids, and fuels and are also useful as intermediates in the preparation of other products (e.g., succinimides) useful as additives in lubricating oils, functional fluids, and fuels.

Abstract: The use of magnesium oxide of specified, low, reactivity in a process for the production of overbased magnesium sulphonates, together with the introduction of water and an alcohol, into the reaction mixture during carbonation, makes it possible to prepare high base number products which have very low post carbonation sediments and which can be purified by rapid filtration.