Abstract: A novel lubricating grease that is useful for underwater applications is made up of lubricating oil that contains a co-polymer of a hydrocarbon backbone for promoting good adhesion and a fluorine containing backbone for promoting lubricity. The grease formulation is resistant to water washout and does not off-gas toxic compounds. In addition to the lubricating oil, the grease formulation includes fumed silica, and may contain one or more corrosion inhibitors, an extreme pressure filler such as boron nitride, and optionally one or more polyurethane initiators.
Abstract: Disclosed are a lubricant composition to which is added as buffer particles to a lubricant polyurethane resin particles obtained by reacting and synthesizing long-chain polyol having a number-average molecular weight of not less than 500, a crosslinking agent having three or more active hydrogen groups in one molecule, and polyisocyanate as buffer particles, a speed reduction gear filled with the lubricant composition, and an electric power steering apparatus having the speed reduction gear incorporated therein, wherein noise produced by the speed reduction gear can be made lower than ever before irrespective of the magnitude of backlash in a case where a worm and a worm wheel are combined with each other and without complicating the configuration of the speed reduction gear by the buffer action of the buffer particles added to the lubricant composition, thereby making it possible to reduce noise produced in an automobile due to the electric power steering apparatus at low cost.
Type:
Grant
Filed:
March 17, 2005
Date of Patent:
May 4, 2010
Assignees:
Koyo Seiko Co., Ltd., Nippon Polyurethane Industry Co., Ltd.
Abstract: Fluorinated oligourethanes, having number average molecular weight lower than or equal to 9,000, having a branched structure, formed of the following monomers and macromers: a) aliphatic, cycloaliphatic or aromatic polyisocyanates, b) heterofunctional hydrogenated monomers having general formula: X0—(CR1AR2A)b—Y0 ??(Ib) one or more of the following compounds: c) bifunctional hydroxyl (per)fluoropolyethers (PFPE diols) having number average molecular weight in the range 400-3,000, e) monofunctional hydroxyl (per)fluoropolyethers or monofunctional hydroxyl (per)fluoroalkanes (e?), having number average molecular weight in the range 300-1,000, and optionally the following compounds: d) heterofunctional monomers, dI) hydrogen-active compounds, capable to form bonds with the NCO functions stable at the hydrolysis but weak at heat.
Abstract: Use of fluorinated polyurethanes thermally crosslinkable for obtaining coatings having an improved friction coefficient for the dry lubrication of rubbers, plastics, metals, glass, said polyurethanes obtainable from aqueous dispersions of cationic oligourethanes having a molecular weight≦9,000, formed by:
a) polyisocyanates, having NCO functionality higher than 2,
b) bifunctional hydrogenated monomers,
c) bifunctional hydroxylated (per)fluoropolyethers,
e) monofunctional hydroxyl or carboxylic (per)fluoropolyethers or monofunctional hydroxyl (per)fluoroalkanes optionally:
d) hydrogenated monomers by which it is possible to insert a crosslinkable chemical function in the oligourethane;
dI) hydrogen-active compounds, able to form with the NCO functions thermolabile bonds.
Abstract: Use of fluorinated polyurethanes thermally crosslinkable for obtaining coatings having an improved friction coefficient for the dry lubrication of rubbers, plastics, metals, glass, said polyurethanes obtainable from aqueous dispersions of cationic oligourethanes having a molecular weight ≦9,000, formed by: a) polyisocyanates, having NCO functionality higher than 2, b) bifunctional hydrogenated monomers, c) bifunctional hydroxylated (per)fluoropolyethers, e) monofunctional hydroxyl or carboxylic (per)fluoropoly-ethers or monofunctional hydroxyl (per)fluoroalkanes optionally: d) hydrogenated monomers by which it is possible to insert a crosslinkable chemical function in the oligourethane; dI) hydrogen-active compounds, able to form with the NCO functions thermolabile bonds.