Lubricant composition
AssigneeEquus UK Topco Ltd
InventorsIan Stuart Hobday, Aitziber Viadas Cienfuegos, John Eastwood
Life of this patent
Estimating the term…
Abstract
The present invention provides a non-aqueous lubricant composition comprising a base stock and 5 at least 0.02 wt % of a friction reducing additive which comprises a block co-polymer of at least one block A which is an oligo- or polyester residue of a hydroxycarboxylic acid and at least one block B which is a residue of a polyalkylene glycol. The invention also provides the use of a block co-polymer of at least one block A which is an oligo- or polyester residue of a hydroxycarboxylic acid and at least one block B which is a residue of a polyalkylene glycol to reduce the kinetic co-efficient 10 of friction in a non-aqueous lubricant composition when compared to an equivalent lubricant composition comprising no block co-polymer.
Claims16
A non-aqueous lubricant composition comprising:
- a base stock;
- and
- at least 0.5 wt % of a friction reducing additive which comprises a mixture of a first and second block co-polymer, wherein
- the first and second block co-polymer each comprise at least one block A with a molecular weight in a range of 1000 to 2500 which is an oligo- or polyester residue of a saturated and an aliphatic hydroxycarboxylic acid that is a hydroxystearic acid,
- the first block co-polymer comprises at least one block B having a molecular weight in a range of 400 to 4600 which is a residue of a polyethylene glycol, and
- the second block co-polymer comprises at least one block B having a molecular weight in a range of 3000 to 5000 which is a residue of a polyethylene glycol;
- wherein the first and second block co-polymer have an ABA structure and the mixture of the first and second block co-polymers has an HUB value of at least 6.5, and
- wherein the lubricant composition at 40° C. to 150° C. reduces kinetic coefficient of friction by at least 20% when measured by a mini-traction machine at 0.01 m/s and 0.02 m/s when compared with an equivalent lubricant composition which does not comprise the friction reducing additive.
A non-aqueous lubricant composition consisting essentially of:
- a base stock;
- at least 0.5% of a friction reducing additive which comprises a mixture of a first and second block co-polymer, wherein
- the first block co-polymer comprises at least one block A with a molecular weight in a range of 1000 to 2500 which is an oligo- or polyester residue of a saturated and an aliphatic hydroxycarboxylic acid that is a hydroxystearic acid,
- the first block co-polymer comprises at least one block B having a molecular weight in a range of 400 to 4600 which is a residue of a polyethylene glycol,
- the second block co-polymer comprises at least one block 13 having a molecular weight in a range of 3000 and 5000 which is a residue of a polyethylene glycol;
- and
- wherein the first and second block co-polymer have an ABA structure and the mixture of the first and second block co-polymers has an MB value of at least 6.5, and
- wherein the lubricant composition at 40° C. to 150° C. reduces kinetic coefficient of friction by at least 20% when measured by a mini-traction machine at 0.01 m/s and 0.02 m/s when compared with an equivalent lubricant composition which does not comprise the friction reducing additive.
A method of reducing the kinetic co-efficient of friction in a non-aqueous lubricant composition, the method comprising:
- blending a base stock with at least 0.5 wt % of a mixture of a first and second block co-polymer to form a lubricant composition, wherein
- the first and second block co-polymer each comprise at least one block A with a molecular weight in a range of 1000 to 2500 which is an oligo- or polyester residue of a saturated and an aliphatic hydroxycarboxylic acid that is a hydroxystearic acid,
- the second block co-polymer comprises at least one block B having a molecular weight in a range of 400 to 4600 which is a residue of a polyethylene glycol, and
- the second block co-polymer comprises at least one block B having a bolecular weight in a range of 3000 to 5000 which is a residue of a polyethylene glycol;
- wherein the first and second block co-polymer have an ABA structure and the mixture of the first and second block co-polymer have an HLB value of at least 6.5, and
- wherein the lubricant composition at 40° C. to 150° C. reduces kinetic coefficient of friction by at least 20% when measured by a mini-traction machine at 0.01 m/s and 0.02 m/s when compared with an equivalent lubricant composition which does not comprise the mixture of the first and second block co-polymer.
Dependencies are inferred from the claim text.