Kyodo Yushi Co. and NTN Corporation | Date: 2017-01-18
The invention provides a grease composition for a wheel bearing, containing (a) a base oil consisting of a mineral oil and a synthetic hydrocarbon oil, wherein the ratio of the synthetic hydrocarbon oil to the total amount of the mineral oil and the synthetic hydrocarbon oil is 40 to 60 mass%, and the base oil has a kinematic viscosity at 40C of 40 to 65 mm^(2)/s; (b) a thickener of formula (A) wherein R^(2) is diphenylmethane, and R^(1) and R^(3), which may be the same or different from each other, each represent cyclohexyl group or a straight-chain or branched alkyl group having 16 to 20 carbon atoms, with a molar ratio of the cyclohexyl group to the total number of moles of the cyclohexyl group and the alkyl group, expressed by [((the number of cyclohexyl groups) / (the number of cyclohexyl groups + the number of alkyl groups)) x 100] being 50 to 90 mol%; (c) an amine type antioxidant; and (d) an amine phosphate type antiwear agent.
NSK Ltd. and Kyodo Yushi Co. | Date: 2015-10-07
A grease-filled bearing filled with a grease composition containing a thickener which is a diurea compound represented by R_(1)-NHCONH-R_(2)-NHCONH-R_(3) or a mixture thereof and a base oil containing alkyl diphenyl ether oil and containing poly -olefin oil as an optional component at a mass ratio of 40:60 to 100:0 (alkyl diphenyl ether oil:poly -olefin oil). In general formula (1), at least one of R_(1) and R_(3) is a C_(6-12) aromatic hydrocarbon group and the other is a C_(6-12) aromatic hydrocarbon group or a C_(6-20) aliphatic hydrocarbon group. R_(2) is a C_(6-15) aromatic hydrocarbon group.
Kyodo Yushi Co. and Nidec Corporation | Date: 2016-04-28
The invention provides a lubricating oil for fluid dynamic bearing including as a base oil a monoester oil free of unsaturated bond, and having an absolute viscosity of 2.0 to 3.0 mPas at 100 C. a viscosity index of 130 or more and a pour point of 20 C. or less.
NSK Ltd. and Kyodo Yushi Co. | Date: 2015-11-04
A rolling bearing in which multiple rolling elements are disposed between an inner ring and an outer ring in such a state that the rolling elements can roll and which is filled with a grease composition that is obtained by adding three kinds of rust preventives to a base oil consisting of at least one mineral or synthetic oil and exhibiting a kinematic viscosity of 200 to 400mm^(2)/s at 40C and that exhibits a cone penetration of 300 to 400 and a yield stress at 40C of 150Pa or less, said three kinds of rust preventives being a carboxylic acid-based rust preventive, a carboxylic salt-based rust preventive and an amine-based rust preventive.
Kyodo Yushi Co. | Date: 2015-02-18
The invention provides a silicone grease composition where the high friction properties are improved, with no decrease of the wear preventive characteristics. The silicone grease composition contains a thickener, a base oil containing a silicone oil in an amount of 50 mass % or more of the total mass of the base oil, and a metallic oxide with a Mohs hardness of 6 or less as a friction modifier.
Kyodo Yushi Co. | Date: 2015-04-22
A grease is provided which has an improved inflow property of the grease into a lubrication unit and has a long life when used for bearings even under a high temperature environment. A grease composition comprising a base oil and a thickener, characterized in that the base oil contains an ester synthetic oil, the content of the ester synthetic oil is not less than 20% by mass of the total mass of the base oil and the thickener contains a diurea compound represented by the Formula (I): R^(1)NHCONHR^(2)NHCONHR^(3),(I) wherein R^(2 )is a C_(6-15 )divalent aromatic hydrocarbon group, R^(1 )and R^(3 )are the same or different, and represent cyclohexyl or C_(8-22 )linear or branched alkyl, and the molar ratio of cyclohexyl to the total of cyclohexyl and C_(8-22 )linear or branched alkyl is 60 to 95%.
Kyodo Yushi Co. and Denso Corporation | Date: 2016-06-08
The invention provides a grease composition containing a base oil, a thickener, and an anti-flaking additive such as a compound represented by, for example, formula (1-1), which grease composition can prevent the white layer flaking of the rolling bearings. (In the formula, R1 and R4 are each independently a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms.)
Kyodo Yushi Co. | Date: 2015-05-20
The invention provides a grease composition containing a urea thickener represented by formula (1):R^(1)-NHCONH-R^(2)-NHCONH-R^(3)(1)(wherein R^(2) is a bivalent aromatic hydrocarbon group having 6 to 15 carbon atoms; and R^(1) and R^(3), which may be the same or different from each other, represent an alkyl group having 8 to 22 carbon atoms, cyclohexyl group or an aryl group having 6 to 12 carbon atoms); and a base oil containing at least one compound represented by formula (3):^(6) and R^(7), which may be the same or different from each other, represent a branched alkyl group having 10 to 26 carbon atoms, with the ratio of the number of moles of the alkyl groups represented by R^(6) and R^(7) where the carbon atom attached to the phenyl ring is a quaternary carbon atom being 40 to 95 mol% with respect to the total number of moles of the branched alkyl groups; and m and n are real numbers of 0 or more so as to satisfy the condition of 1.0m+n3.0).
Kyodo Yushi Co. | Date: 2015-10-21
The invention provides a grease composition containing a thickener, a base oil and an amine phosphate.
Kyodo Yushi Co. and NTN Corporation | Date: 2016-10-12
The invention provides a grease composition for constant velocity joints, which contains (a) a base oil, (b) a diurea thickener, (c) benzotriazole and/or a derivative thereof, and (d) a phosphate and/or an amine salt thereof; and a constant velocity joint where the grease composition is packed.