# US 7,410,935 B2 · Gear fluids > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,410,935 B2 - Document ID: US7410935B2 - Status: Granted - Kind: B2 - Application number: 11/386,436 - Filed: 2006-03-22 - Published: 2007-09-27 - Granted: 2008-08-12 - Earliest claimed: 2006-03-22 - Assignees: Afton Chemical Corporation - Inventors: Chip Hewette - Web page: https://patentgrep.com/patent/US7410935B2 ## CPC - C10M 137/00: Lubricating compositions characterised by the additive being an organic non-macromolecular compound containing phosphorus - C10M 137/08: Ammonium or amine salts - C10M 137/12: having a phosphorus-to-carbon bond - C10M 169/04: Mixtures of base-materials and additives - C10M 2203/065: used as base material - C10M 2223/043: Ammonium or amine salts thereof - C10M 2223/06: having phosphorus-to-carbon bonds - C10N 2030/06: Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure - C10N 2030/70: {Soluble oils} - C10N 2040/04: Oil-bath; Gear-boxes; Automatic transmissions; Traction drives - C10N 2040/042: {for automatic transmissions} - C10N 2040/044: {for manual transmissions} - C10N 2040/045: {for continuous variable transmission [CVT]} - C10M: LUBRICATING COMPOSITIONS (well drilling compositions C09K8/02); USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION (mould release, i.e. separating, agents for metals B22C3/00, for plastics or substances in a plastic state, in general B29C33/56, for glass C03B40/02; textile lubricating compositions D06M11/00, D06M13/00, D06M15/00; immersion oils for microscopy G02B21/33) - C10N: INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS ## Abstract A gear fluid composition for extreme pressure applications. The composition includes a base oil component and a friction modifier mixture. The mixture is provided by an alkyl phosphonic acid diester of the formula: wherein R1 is a hydrocarbyl group containing from about 8 to about 24 carbon atoms, R2 and R3 are selected from a hydrocarbyl group containing from about 1 to about 8 carbon atoms, an alkyl phosphonic acid monoester of the formula wherein R4 is a hydrocarbyl group containing from about 8 to about 24 carbon atoms, R5 is hydrogen or hydrocarbyl group containing from about 1 to about 8 carbon atoms, and an amine salt of a partial ester of phosphoric acid represented by the formula wherein each of R6 and R8 is a hydrocarbyl group, and R7 is hydrogen or a hydrocarbyl group, and wherein the ratio of (i) to (ii) ranges from about 3 to about 5.5. ## Claims ### Claim 1 An gear additive composition, comprising: (a) a base oil component; and (b) a friction modifier mixture including: (i) at least one alkyl phosphonic acid diester of the formula: wherein R1 is a hydrocarbyl group containing from about 8 to about 24 carbon atoms, R2 and R3 are independently selected from a hydrocarbyl group containing from about 1 to about 8 carbon atoms; (ii) at least one alkyl phosphonic acid monoester of the formula wherein R4 is a hydrocarbyl group containing from about 8 to about 24 carbon atoms, R5 is selected from hydrogen and a hydrocarbyl group containing from about 1 to about 8 carbon atoms; and (iii) at least one amine salt of a partial ester of phosphoric acid represented by the formula wherein each of R6 and R8 is, independently, a hydrocarbyl group, and R7 is hydrogen or a hydrocarbyl group, and wherein the ratio of (i) to (ii) ranges from about 3 to about 5.5. ### Claim 2 (depends on 1) The additive composition of claim 1, wherein the base oil component comprises an alkylated naphthalene blendstock. ### Claim 3 (depends on 1) The additive composition of claim 1, wherein the base oil component comprises a mono-alkylated naphthalene. ### Claim 4 (depends on 1) The additive composition of claim 1, wherein the alkyl phosphonic acid diester is selected from the group consisting of dimethyloctadecylphosphonate, dimethyloctadecenylphosphonate, diethyl-2-ethyldecylphosphonate, ethylpropyl-1-butylhexadecylphosphonate, methylethyloctadecylphosphonate, methylbutyl eicosylphosphonate, dimethylhexatriacontylphosphonate. ### Claim 5 (depends on 1) The additive composition of claim 1, wherein the alkyl phosphonic acid monoester is derived from the alkyl phosphonic acid diester. ### Claim 6 (depends on 1) The additive composition of claim 1, wherein the amine salt is derived from 2-ethylhexyl acid phosphate. ### Claim 7 (depends on 1) The additive composition of claim 1, wherein the amine salt is derived from oleylamine. ### Claim 8 (depends on 1) The additive composition of claim 1, comprising from about 1 to about 10 percent by weight of the monoester and diester of phosphonic acid. ### Claim 9 (depends on 1) The additive composition of claim 1, comprising from about 10 to about 30 percent by weight of the amine salt of the phosphoric acid. ### Claim 10 (depends on 1) The additive composition of claim 1, comprising from about 50 to about 70 percent by weight of the base oil component. ### Claim 11 (depends on 1) The additive composition of claim 1, further comprising an antioxidant, an antiwear agent, an antifoam agent, and a viscosity index improver. ### Claim 12 (depends on 1) A gear fluid containing an effective amount of the additive composition of claim 1. ### Claim 13 (depends on 12) The gear fluid of claim 12, wherein the gear fluid comprises from about 3 to about 6 percent by weight of the additive composition. ### Claim 14 (depends on 1) An axle containing the additive composition of claim 1. ### Claim 15 (depends on 14) The axle of claim 14, wherein the axle comprises a limited slip differential. ### Claim 16 (depends on 1) The additive composition of claim 1, wherein the additive composition is applied to a limited slip axle as a top treat fluid. ### Claim 17 A method of improving the solubility of one or more friction modifier components in a friction modifier additive package comprising blending at least one alky phosphonic acid diester of the formula: with at least one alkyl phosphonic acid monoester of the formula: and with at least one amine salt of a partial ester of phosphoric acid represented by the formula wherein R1 and R4 are selected from a hydrocarbyl group containing from about 8 to about 24 carbon atoms; R2, R3 and R5 are independently selected from hydrogen and a hydrocarbyl group containing from about 1 to about 8 carbon atoms; and each of R6 and R8 is, independently, a hydrocarbyl group, and R7 is hydrogen or a hydrocarbyl group, wherein the foregoing components are blended in an amount of a base oil component sufficient to solubilize substantially all of the alkyl phosphonic acid monoester and diester, and wherein the ratio of the diester to the monoester of the alkyl phosphonic acids ranges from about 3 to about 5.5. ### Claim 18 (depends on 17) The method of claim 17, wherein the base oil component comprises an alkylated naphthalene blendstock. ### Claim 19 (depends on 17) The method of claim 17, wherein the base oil component comprises a mono-alkylated naphthalene. ### Claim 20 (depends on 17) The method composition of claim 17, wherein the alkyl phosphonic acid diester is selected from the group consisting of dimethyloctadecylphosphonate, dimethyloctadecenylphosphonate, diethyl-2-ethyldecylphosphonate, ethylpropyl-1-butylhexadecylphosphonate, methylethyloctadecylphosphonate, methylbutyl eicosylphosphonate, dimethylhexatriacontylphosphonate. ### Claim 21 (depends on 17) The method of claim 17, wherein the amine salt is derived from 2-ethylhexyl acid phosphate. ### Claim 22 (depends on 17) The method of claim 17, wherein the amine salt is derived from oleylamine. ### Claim 23 (depends on 17) The method of claim 17, comprising mixing from about 1 to about 10 percent by weight of the alkyl phosphonic acid diester with from about 0.5 to about 1.5 percent by weight of the alkyl phosphonic acid monoester, and with from about 10 to about 30 percent by weight of the amine salt of the partial ester of phosphoric acid in the base oil component. ### Claim 24 (depends on 17) The method of claim 17, comprising blending from about 50 to about 70 percent by weight of the base oil component with the alkyl phosphonic acid monoester, with the alkyl phosphonic acid diester, and with the amine salt of the partial ester of phosphoric acid. ### Claim 25 (depends on 17) A top-treat additive package made by the method of claim 17. ### Claim 26 A method for improving the friction performance of a gear fluid comprising providing an additive package to a gear fluid, the additive package comprising a base oil component and a friction modifier mixture including: (i) at least one alkyl phosphonic acid diester of the formula: wherein R1 is a hydrocarbyl group containing from about 8 to about 24 carbon atoms, R2 and R3 are independently selected from a hydrocarbyl group containing from about 1 to about 8 carbon atoms; (ii) at least one alkyl phosphonic acid monoester of the formula wherein R4 is a hydrocarbyl group containing from about 8 to about 24 carbon atoms, R5 is selected from hydrogen and a hydrocarbyl group containing from about 1 to about 8 carbon atoms; and (iii) at least one amine salt of a partial ester of phosphoric acid represented by the formula wherein each of R6 and R8 is, independently, a hydrocarbyl group, and R7 is hydrogen or a hydrocarbyl group, and wherein the ratio of (i) to (ii) ranges from about 3 to about 5.5. ### Claim 27 (depends on 26) The method of claim 26, wherein the additive package is suitable for use in a limited slip differential. ### Claim 28 (depends on 26) The method of claim 26, wherein the gear fluid comprises from about 0.03 to about 0.5 percent by weight of the alkyl phosphonic acid diester based on the total weight of the gear fluid. ### Claim 29 (depends on 26) The method of claim 26, wherein the additive packages is added to the gear fluid in an amount ranging from about 1 to about 10 percent of the total weight of the gear fluid.