Patent ID: 6815402
Filing Date: 2004-11-09
Classification: C10M,C10N

Abstract:
A lubricating oil composition which comprises a base oil and at least one compound selected from cyclic organic phosphorus compounds represented by the following general formula (I): wherein Z represents (1) hydrogen atom, (2) an alkyl group, (3) a cycloalkyl group which may be substituted with alkyl groups having 1 to 12 carbon atoms and/or hydroxyl group, (4) an aryl group which may be substituted with alkyl groups having 1 to 12 carbon atoms and/or hydroxyl group or (5) an alkyl group substituted with an aryl group, which aryl group may be substituted with at least one of alkyl groups having 1 to 12 carbon atoms and hydroxyl group, X1 and X2 each independently represent a halogen atom or hydroxyl group and p and q each represent an integer 0 to 3,wherein the base oil is at least one oil selected from the group consisting of: purified mineral oils. alkylbenzenes, poly-&agr;-olefins, polyvinyl ethers, polycarbonates, polyoxyalkylene glycols represented by general formula (V): R1â€”[(OR2)mâ€”OR3]nâ€ƒâ€ƒ(V) wherein R1 represents hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an acyl group having 2 to 10 carbon atoms or an aliphatic hydrocarbon group having 1 to 10 carbon atoms and 2 to 6 bonding portions; R2 represents an alkylene group having 2 to 4 carbon atoms; represents hydrogen atom, an alkyl group having 1 to 10 carbon atoms or an acyl group having 2 to 10 carbon atoms; n represents an integer of 1 to 6; and m represent numbers giving an average value of numbers represented by mÃ—n in a range of 6 to 80, polyoxyalkylene glycol derivatives having at least one constituting unit represented by general formula (VI): â€ƒwherein R4 to R7 each represent hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms or a group represented by general formula (VII): â€ƒand at least one of R4 to R7 represents a group represented by general formula (VII), and wherein R8 and R9 each represent hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms. R10 represents an alkylene group having 2 to 5 carbon atoms, a substituted alkylene group having alkyl groups as the substituents and 2 to 5 carbon atoms in the entire group or a substituted alkylene group having alkoxyalkyl groups as the substituents and 4 to 10 carbon atoms in the entire group, n represents an integer of 0 to 20 and R11 represents a monovalent hydrocarbon group having 1 to 10 carbon atoms, esters of polybasic carboxylic acids, diesters obtained by esterification of addition products of alkylene oxides to monohydric alcohols with aliphatic dicarboxylic acids, esters obtained by esterification of addition products of 1 to 10 moles of alkylene oxides to polyhydric alcohols, ester oligomers of fumaric acid, esters of hydroxypivalic acid, and esters of aliphatic polyhydric alcohols and linear or branched fatty acids, said aliphatic polyhydric alcohols being at least one selected from the group consisting of ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, trimethylolethane, ditrimethylolethane, ditrimethylolpropane, glycerol, pentaerythritol, dipentaerythritol, tripentaerythritol and sorbitol.