# US 5,705,085 A · Organomolybdenum-containing magnetorheological fluid > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,705,085 A - Document ID: US5705085A - Status: Granted - Kind: A - Application number: 08/664,075 - Filed: 1996-06-13 - Granted: 1998-01-06 - Earliest claimed: 1996-06-13 - Assignees: Lord Corporation - Inventors: Beth C. Munoz; Anthony J. Margida; Thomas J. Karol - Web page: https://patentgrep.com/patent/US5705085A ## CPC - H01F 1/447: {characterised by magnetoviscosity, e.g. magnetorheological, magnetothixotropic, magnetodilatant liquids (electrorheological fluids C10M171/001)} - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES ## Abstract A magnetorheological fluid that includes magnetic-responsive particles, a carrier fluid and an organomolybdenum. The organomolybdenum preferably includes at least one molybdenum atom bonded to at least one organic moiety wherein the organic moiety can be derived from a precursor selected from the group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an oxygen-containing compound, a nitrogen-containing compound and a compound containing more than one functional group. ## Claims ### Claim 1 A magnetorheological fluid comprising magnetic-responsive particles, a carrier fluid and at least one organomolybdenum. ### Claim 2 (depends on 1) A magnetorheological fluid according to claim 1, wherein the organomolybdenum comprises at least one molybdenum atom bonded to at least one organic moiety. ### Claim 3 (depends on 2) A magnetorheological fluid according to claim 2, wherein the organic moiety is derived from a precursor selected from the group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an oxygen-containing compound, a nitrogen-containing compound and a compound containing more than one functional group. ### Claim 4 (depends on 2) A magnetorheological fluid according to claim 2, wherein the organomolybdenum is selected from the group consisting of an organomolybdenum complex prepared by reacting a fatty oil, diethanolamine and a molybdenum source; a heterocyclic molybdenum prepared by reacting a diol, a diamino-thiol-alcohol, an amino-alcohol and a molybdenum source; and an organomolybdenum prepared by reacting an amine-amide with a molybdenum source. ### Claim 5 (depends on 1) A magnetorheological fluid according to claim 1, wherein the organomolybdenum is present in amount of 0.1 to 12 volume percent, based on the total volume of the magnetorheological fluid. ### Claim 6 (depends on 1) A magnetorheological fluid according to claim 1, wherein the magnetic-responsive particles have an average particle size of 0.1 to 500 .mu.m. ### Claim 7 (depends on 1) A magnetorheological fluid according to claim 1, wherein the magnetic-responsive particles have an average particle size of at least 1 .mu.m. ### Claim 8 (depends on 1) A magnetorheological fluid according to claim 1, wherein the carrier fluid comprises at least one fluid selected from the group consisting of natural fatty oil, mineral oil, polyphenylether, dibasic acid ester, neopentylpolyol ester, phosphate ester, polyester, cycloparaffin oil, paraffin oil, unsaturated hydrocarbon oil, synthetic hydrocarbon oil, monobasic acid ester, glycol ester, glycol ether, perfluorinated polyether and halogenated hydrocarbon. ### Claim 9 (depends on 8) A magnetorheological fluid according to claim 8, wherein the carrier fluid is selected from the group consisting of mineral oil, paraffin, cycloparaffin, naphthenic oil and synthetic hydrocarbon. ### Claim 10 (depends on 9) A magnetorheological fluid according to claim 9, wherein the carrier fluid comprises a synthetic hydrocarbon derived from polyalphaolefin. ### Claim 11 (depends on 1) A magnetorheological fluid according to claim 1, wherein the magnetic-responsive particles have an average particle size of 0.1 to 500 .mu.m, the carrier fluid is selected from the group consisting of mineral oil, paraffin, cycloparaffin, naphthenic oil and synthetic hydrocarbon, and the organomolybdenum comprises at least one molybdenum atom bonded to at least one organic moiety, wherein the organic moiety is derived from a precursor selected from the group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an oxygen-containing compound, a nitrogen-containing compound and a compound containing more than one functional group. ### Claim 12 (depends on 1) A magnetorheological fluid according to claim 1, further comprising at least one second additive. ### Claim 13 (depends on 12) A magnetorheological fluid according to claim 12, wherein the second additive is selected from the group consisting of a phosphate and a sulfur-containing compound. ### Claim 14 (depends on 13) A magnetorheological fluid according to claim 13, wherein the phosphate is selected from the group consisting of alkyl, aryl, alkylaryl, arylalkyl, amine and alkyl amine phosphate. ### Claim 15 (depends on 13) A magnetorheological fluid according to claim 13, wherein the phosphate is selected from the group consisting of tricresyl phosphate, trixylenyl phosphate, dilauryl phosphate, octadecyl phosphate, hexadecyl phosphate, dodecyl phosphate, didodecyl phosphate, and an alkyl amine phosphate. ### Claim 16 (depends on 12) A magnetorheological fluid according to claim 12, wherein the sulfur-containing compound is selected from the group consisting of thiol and thioester. ### Claim 17 (depends on 12) A magnetorheological fluid according to claim 12, wherein the second additive is present in amount of 0.1 to 12 volume percent, based on the total volume of the magnetorheological fluid. ### Claim 18 (depends on 1) A magnetorheological fluid according to claim 1, further comprising at least one carboxylate soap. ### Claim 19 (depends on 1) A magnetorheological fluid according to claim 1, further comprising a polymer-modified metal oxide. ### Claim 20 (depends on 1) A magnetorheological fluid according to claim 1, further comprising a phosphate, a carboxylate soap and a polymer-modified metal oxide. ### Claim 21 (depends on 18) A magnetorheological fluid according to claim 18 wherein the carboxylate soap is selected from the group consisting of lithium stearate, calcium stearate, aluminum stearate, ferrous oleate, ferrous naphthenate, zinc stearate, sodium stearate and strontium stearate.