Grease composition

Patent metadata

Field	Value
Publication number	US-10077411-B2
Application number	US-201414909377-A
Country	US
Kind code	B2
Filing date	Aug 4, 2014
Priority date	Aug 2, 2013
Publication date	Sep 18, 2018
Grant date	Sep 18, 2018

Abstract

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.)

First claim

The invention claimed is:

1. A grease composition, comprising a base oil, a thickener, and an anti-flaking additive selected from the group consisting of a compound represented by formula (1-1):

wherein R 1 and R 4 are each a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms;
sulfurized oil fat; and
olefin sulfide,
wherein the base oil is a synthetic oil selected from the group consisting of ester synthetic oils obtained from a polyol, a monovalent fatty acid and a polybasic acid, hydrocarbon synthetic oils, and ether synthetic oils,
wherein the thickener is a diurea compound represented by formula (I-1):

or
a mixture of a diurea compound represented by formula (I-2-1), a diurea compound represented by formula (I-2-2) and a diurea compound represented by formula (I-2-3),

with the ratio of the number of moles of the cyclohexyl groups to the total number of moles of the cyclohexyl groups and the straight-chain alkyl groups having 18 carbon atoms being in the range of 70 to 90 mol %,
wherein the base oil is contained in an amount of 90 to 70 mass % based on the total mass of the grease composition,
wherein the thickener is contained in an amount of 5 to 20 mass % based on the total mass of the grease composition, and
wherein the anti-flaking additive is contained in an amount of 0.5 to 10 mass % based on the total mass of the grease composition.

2. The grease composition of claim 1 , wherein the anti-flaking additive is the 2,5-dimercapto-1,3,4-thiazole derivative of formula (1-1) wherein R1 and R4 are both straight-chain alkyl groups having eight carbon atoms; the sulfurized oil fat; or the olefin sulfide.

3. The grease composition of claim 1 , wherein the base oil has a kinematic viscosity at 40° C. of 20 to 500 mm 2 /s.

4. The grease composition of claim 1 , wherein the base oil has a kinematic viscosity at 40° C. of 50 to 500 mm 2 /s.

5. The grease composition of claim 1 , wherein the base oil is selected from the group consisting of poly α-olefins; alkyl diphenyl ether; and ester synthetic oil obtained from pentaerythritol, adipic acid, heptanoic acid, caprylic acid and capric acid.

Assignees

• Kyodo Yushi
• Denso Corp

Inventors

• Yoshinari Terasu
• Komoriya Tomonobu
• Hirooka Iwaki
• Muto Masataka
• Nakazawa Satoru
• Fukushima Yoshinori
• Mori Shigeyuki

Classifications

• C10N2050/10

  semi-solid; greasy · CPC title

• C10N2040/02

  Bearings · CPC title

• C10N2030/06

  Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure · CPC title

• C10M2219/102

  containing sulfur and carbon only in the ring · CPC title

• C10M2219/086

  containing sulfur atoms bound to carbon atoms of six-membered aromatic rings · CPC title