A polyester is useful as a high viscosity base fluid. A method for its preparation involves epoxidizing an alpha-olefin, reacting the alpha-epoxide or diol with a saturated linear aliphatic dicarboxylic acid, and isolating the polyester. Lubricant compositions can contain such polyesters and the compositions are useful as automatic transmission fluids, manual transmission fluids, continuously variable transmission fluids, gear oil formulations, industrial gear oil formulations, axle fluid formulations, dual clutch transmission fluids, dedicated hybrid transmission fluids, or as hydraulic oils.

A lubricant base oil of the present invention includes an ester compound including: a structural moiety (A) that is derived from an alcohol compound (A); and a structural moiety (B) that is derived from a carboxylic acid, the structural moiety B including: a structural moiety (B1) that is derived from a monocarboxylic acid (B1); and a structural moiety (B2) that is derived from an aliphatic monocarboxylic acid (B2) having 4 or more and 18 or less carbon atoms. According to the present invention, it is possible to provide a lubricant base oil having excellent low-temperature stability and high heat resistance while maintaining torque-lowering properties.

The present disclosure generally relates to alkylated aromatic compounds useful as basestocks and additives for high viscosity applications. In an embodiment is provided an alkylated aromatic compound. In another embodiment is provided a lubricant formulation that includes an alkylated aromatic compound. In another embodiment is provided a lubricant formulation that includes an alkylated aromatic compound, an additive, and optionally, a Group III basestock, Group IV basestock, Group V basestock, or a combination thereof, the Group V basestock being different than the alkylated aromatic compound. In another embodiment is provided a method of forming a lubricant formulation that includes introducing a mPAO, an aromatic compound, and an acid catalyst to a reactor under reactor conditions to form an alkylated aromatic compound; and introducing the alkylated aromatic compound to an additive to form a lubricant formulation.

Traction fluids comprising Formula I, II, III, IV, V, VI, VII or a mixture thereof in combination with a base stock, a viscosity modifier, an anti-foaming agent, and an additive package.

The present invention aims to provide a viscosity-index improving agent having an excellent friction reduction effect to reduce friction of a lubricating oil composition when the viscosity-index improving agent is added thereto. The present also aims to provide a lubricating oil composition containing the viscosity-index improving agent. The present invention relates to, for example, a viscosity-index improving agent containing: (co)polymer (A) containing, as an essential constituent monomer, a polyolefin-based monomer (a) represented by the following formula (1); an ester oil (B1) having a kinematic viscosity at 100 C. of 1.00 to 2.50 mm.sup.2/s; and an ester oil (B2) having a kinematic viscosity at 100 C. of 2.51 to 5.00 mm.sup.2/s: ##STR00001##
wherein R.sup.1 is a hydrogen atom or a methyl group; X.sup.1 is a group represented by O, O(AO).sub.m-, or NH, A is a C2-C4 alkylene group, m is an integer of 1 to 10, and each A may be the same or different when m is 2 or more; R.sup.2 is a residue after removal of one hydrogen atom from a hydrocarbon polymer containing a 1,2-butylene group as a structural unit; and p represents a number of 0 or 1.

This invention relates to a lubricating oil composition, or concentrate therefor, comprising or resulting from the admixing of: (i) base oil, (ii) one or more styrenic block copolymers having a radial structure where one or more blocks derived from conjugated diene monomers are distal to the radial center and one more blocks derived from vinyl aromatic monomers that are proximal to the radial center, and (iii) optionally one or more dispersants and or detergents.

A high-molecular-weight compound having a plurality of polymer chains linked through a divalent or higher-valent linking group, in which the divalent or higher-valent linking group has a thiol group and at least one of a thioether structure and a thiourethane structure, and a ratio of an absolute weight-average molecular weight to a relative weight-average molecular weight (absolute Mw/relative Mw) of the high-molecular-weight compound is 1.25 or more; and a method for producing the same are provided.

A lubricating oil composition that is hard to increase in viscosity in the low temperature range and is easy to increase in viscosity in the high temperature range. The lubricating oil composition contains a base oil and a viscosity index improver. The base oil contains a mineral oil and an oxygen-containing synthetic oil. The viscosity index improver contains a comb-shaped polymer. The lubricating oil composition has a kinematic viscosity of 100 C. of 9.3 mm.sup.2/s or less, a viscosity index of 280 or more, and a content Y (% by mass) of the oxygen-containing synthetic oil based on the total amount of the lubricating oil composition satisfying the following expression (1): Y<3.7 ln(X)+ (1), where =0.5, =19, and X represents a ratio of the number of carbon atoms and the number of oxygen atoms per one molecule of the oxygen-containing synthetic oil.

A grease composition for heat fixing devices contains a base oil and polytetrafluoroethylene. The base oil contains a perfluoropolyether having at least one of the structures represented by formulas (I) and (II) in the molecule and has a kinematic viscosity v40 of 800 mm.sup.2/s to 2500 mm.sup.2/s at 40 C., and whose kinematic viscosity v200 at 200 C. is 1/50 or less of the kinematic viscosity v40. ##STR00001##

A lubricating oil composition may contain a base oil (A) and a dispersant-type viscosity index improver (B), in which the nitrogen atom content based on the solid content of the dispersant-type viscosity index improver (B) is 0.50 to 1.50% by mass, and the weight-average molecular weight (Mw) thereof is 100,000 or more, and the content in terms of the solid content based on the total amount of the composition of the dispersant-type viscosity index improver (B) is more than 0.05% by mass and less than 5.0% by mass. The lubricating oil composition may exert excellent wear resistance in a state contaminated with soot.