Lubricating grease composition
View Patent ↗A lubricating grease composition comprising base oil and a blended thickener which comprises, as the thickener constituents, (a) one or more urea-type compounds; (b) one or more fatty acid metal salts; and (c) at least one type of amide compound selected from the group comprised of aliphatic amides and aliphatic bisamides shown by the general formulae (1) and (2): R 1 CONH 2 (1) R 1 CONHR 2 NHCOR 1 (2) wherein R 1 denotes a saturated or unsaturated alkyl group having from 15 to 17 carbon atoms and R 2 denotes a methylene group or an ethylene group and wherein the blending weight proportions of (a), (b) and (c) are in the ratio of a/(b+c) is in the range of from 0.20 to 10 wherein (1) constituent (a) has a blending weight ratio in the range of from 1 to 10; (2) constituent (b) has a blending weight ratio in the range of from 0.5 to 2.5; and (3) constituent (c) has a blending weight ratio in the range of from 0.5 to 2.5.
1. A lubricating grease composition comprising base oil and a blended thickener which comprises, as the thickener constituents,
(a) one or more urea-type compounds;
(b) one or more fatty acid metal salts; and
(c) at least one type of amide compound selected from the group comprised of aliphatic amides and aliphatic bisamides shown by the general formulae (1) and (2):
R 1 CONH 2 (1)
R 1 CONHR 2 NHCOR 1 (2)
wherein R 1 denotes a saturated or unsaturated alkyl group having from 15 to 17 carbon atoms and R 2 denotes a methylene group or an ethylene group, and wherein the blending weight proportions of (a), (b) and (c) are in the ratio of
a/(b+c) is in the range of from 0.20 to 10
wherein
(1) constituent (a) has a blending weight ratio in the range of from of 1 to 10;
(2) constituent (b) has a blending weight ratio in the range of from 0.5 to 2.5; and
(3) constituent (c) has a blending weight ratio in the range of from 0.5 to 2.5.
2. The lubricating grease composition of claim 1 wherein the blended thickener is present in an amount in the range of from 2 to 30 wt. % based on the total weight of the lubricating grease composition.
3. The lubricating grease composition of claim 1 wherein the one or more urea-type compounds (a) are urea-type compounds having an average molecular weight in the range of from 500 to 1000.
4. The lubricating grease composition of claim 1 wherein the urea-type compound comprises one or more straight chain hydrocarbon end groups wherein in the range of from 10 to 70 mol % of the straight chain hydrocarbon end groups are unsaturated constituents.
5. The lubricating grease composition of claim 1 wherein the total amine value of the primary amines used to manufacture said one or more urea-type compounds (a) is preferably in the range of from 200 to 500.
6. The lubricating grease composition of claim 1 wherein the one or more fatty acid metal salts are metal salts of straight chain saturated or unsaturated aliphatic monocarboxylic acids having in the range of from 6 to 24 carbon atoms.
7. The lubricating grease composition of claim 1 wherein the one or more fatty acid metal salts comprise metals selected from alkali metals, alkaline earth metals, zinc and aluminium.
8. The lubricating grease composition of claim 1 wherein said lubricating grease composition comprises one or more additives selected from anti-oxidants, corrosion inhibitors, friction modifiers, extreme-pressure additives, anti-wear agents, solid lubricants and metal deactivators or polymers.
9. A method of reducing friction fluctuations in the rolling and/or sliding parts of machines wherein said method comprises lubricating said parts with the lubricating grease composition of claim 1 .
10. A process of using the lubricating grease composition of claim 1 to lubricate an electric power steering apparatus comprising lubricating the electric power steering apparatus.
11. The lubricating grease composition of claim 2 wherein the one or more urea-type compounds (a) are urea-type compounds having an average molecular weight in the range of from 500 to 1000.
12. The lubricating grease composition of claim 2 wherein the urea-type compound comprises one or more straight chain hydrocarbon end groups wherein in the range of from 10 to 70 mol % of the straight chain hydrocarbon end groups are unsaturated constituents.
13. The lubricating grease composition of claim 3 wherein the urea-type compound comprises one or more straight chain hydrocarbon end groups wherein in the range of from 10 to 70 mol % of the straight chain hydrocarbon end groups are unsaturated constituents.
14. The lubricating grease composition of claim 2 wherein the total amine value of the primary amines used to manufacture said one or more urea-type compounds (a) is preferably in the range of from 200 to 500.
15. The lubricating grease composition of claim 3 wherein the total amine value of the primary amines used to manufacture said one or more urea-type compounds (a) is preferably in the range of from 200 to 500.
16. The lubricating grease composition of claim 4 wherein the total amine value of the primary amines used to manufacture said one or more urea-type compounds (a) is preferably in the range of from 200 to 500.
17. The lubricating grease composition of claim 2 wherein the one or more fatty acid metal salts are metal salts of straight chain saturated or unsaturated aliphatic monocarboxylic acids having in the range of from 6 to 24 carbon atoms.
18. The lubricating grease composition of claim 3 wherein the one or more fatty acid metal salts are metal salts of straight chain saturated or unsaturated aliphatic monocarboxylic acids having in the range of from 6 to 24 carbon atoms.
19. The lubricating grease composition of claim 4 wherein the one or more fatty acid metal salts are metal salts of straight chain saturated or unsaturated aliphatic monocarboxylic acids having in the range of from 6 to 24 carbon atoms.
20. The lubricating grease composition of claim 5 wherein the one or more fatty acid metal salts are metal salts of straight chain saturated or unsaturated aliphatic monocarboxylic acids having in the range of from 6 to 24 carbon atoms.