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KR-20260065528-A - LUBRICATING FLUID FOR AN ELECTRIC MOTOR

KR20260065528AKR 20260065528 AKR20260065528 AKR 20260065528AKR-20260065528-A

Abstract

An electric motor lubricating fluid for an electric motor system comprising a lubricating base oil, a tolyltriazole corrosion inhibitor, an oil-soluble phosphorus anti-wear additive, and an amount of sulfonate detergent that promotes effective performance of copper leaching and extreme pressure scuffing in the presence of tolyltriazole.

Inventors

  • 제시카 로드리게즈
  • 마크 데블린
  • 커슬리 딜리언
  • 키스 수티약
  • 안드레 윌리엄스

Assignees

  • 에프톤 케미칼 코포레이션

Dates

Publication Date
20260508
Application Date
20251027
Priority Date
20241101

Claims (15)

  1. As an electric motor lubricating fluid suitable for electric or hybrid-electric vehicles, One or more base oils of lubricating viscosity; At least about 1 ppm of nitrogen provided by the tolyltriazole corrosion inhibitor; A useful phosphorus anti-wear additive comprising ash-free dialkyl dithiophosphate that provides about 40 ppm to about 150 ppm of phosphorus and about 85 ppm to about 315 ppm of sulfur to an electric motor lubricating fluid; A succinimide dispersant derived from a hydrocarbyl-substituted dicarboxylic acid or anhydride reacted with a polyalkylene polyamine having one or more primary or secondary amines—wherein one or more primary or secondary amines are post-treated with a capping agent—; The electric motor lubricating fluid comprises an amount of sulfonate detergent that imparts about 0.02 to about 1.9 TBN (ASTM D2896); An electric motor lubricating fluid containing less than about 500 ppm of sulfur and at least about 70 ppm of phosphorus.
  2. In claim 1, the tolyltriazole corrosion inhibitor is an electric motor lubricating fluid comprising methyl-1H-benzotriazole.
  3. An electric motor lubricating fluid according to claim 1, wherein the ratio of the amount of phosphorus (ppm) transferred from ash-free dialkyl dithiophosphate to the fluid and the amount of nitrogen (ppm) transferred from tolyltriazole corrosion inhibitor to the fluid (EP Phos + CI Nitrogen) with respect to the TBN coefficient is about 70,000 or less, and the TBN coefficient is the TBN (ASTM D2896) transferred to the fluid by the detergent divided by the amount of metal (ppm) transferred from the detergent to the fluid (TBN/Det Metal).
  4. In paragraph 3, the sulfonate cleaner is calcium sulfonate and provides about 30 to about 600 ppm of calcium to the motor lubricating fluid, the motor lubricating fluid.
  5. In claim 1, the useful phosphorus anti-wear additive comprising ashless dialkyl dithiophosphate is prepared by a process comprising the steps of: (a) reacting an organic hydroxy compound with a phosphorus pentasulfide to form a reaction product; and (b) further reacting the reaction product with an unsaturated carboxylic acid to form a useful phosphorus anti-wear additive comprising ashless dialkyl dithiophosphate; and/or; the ashless dialkyl dithiophosphate is a compound of formula I, or a salt thereof: (Chemical Formula IIa) (wherein R 4 and R 5 are independently C 1 to C 10 linear or branched alkyl groups, and R 6 is -H or -CH 3 ) and/or; an ashless dialkyl dithiophosphate comprising 3-[[bis(2-methylpropoxy)phosphinothioil]thio]-2-methylpropanoic acid, an electric motor lubricating fluid.
  6. In claim 1, the succinimide dispersant is post-treated with a phosphorus-containing compound and/or a boron-containing compound; or the succinimide dispersant delivers about 20 to about 100 ppm of phosphorus and about 5 to about 50 ppm of boron to the motor lubricating fluid.
  7. In claim 1, the sulfonate cleaner is provided in an amount imparting about 0.2 to about 0.6 TBN; and/or the motor lubricating fluid exhibits copper leaching of about 30 ppm or less according to ASTM D130; and/or the motor lubricating fluid has a failure load stage rating of 8 or higher in the FZG A10/16.6R/120 test of ASTM D5182; and/or the motor lubricating fluid contains less than about 300 ppm of sulfur.
  8. A method for lubricating driveline components including an electric motor, The method includes the step of lubricating driveline components with motor lubricating fluid, wherein the motor lubricating fluid is in contact with a part of the motor; The motor lubricating fluid comprises (i) one or more base oils of lubricating viscosity, (ii) at least about 1 ppm of nitrogen provided by a tolyltriazole corrosion inhibitor, (iii) a useful phosphorus anti-wear additive comprising an ashless dialkyl dithiophosphate providing about 40 ppm to about 150 ppm of phosphorus and about 85 ppm to about 315 ppm of sulfur to the motor lubricating fluid, (iv) a succinimide dispersant derived from a hydrocarbyl-substituted dicarboxylic acid or anhydride reacted with a polyalkylene polyamine having one or more primary or secondary amines—wherein one or more primary or secondary amines are post-treated with a capping agent—, (v) a sulfonate cleaner provided in an amount imparting about 0.02 to about 1.9 TBN to the motor lubricating fluid; and (vi) the motor lubricating fluid contains less than about 500 ppm of sulfur and at least about 70 ppm of phosphorus; The electric motor lubricating fluid exhibits copper leaching of about 30 ppm or less according to ASTM D130 and has a failure load stage rating of 8 or higher in the FZG A10/16.6R/120 test of ASTM D5182.
  9. In claim 8, the method comprises a triazole corrosion inhibitor including methyl benzotriazole.
  10. In claim 8, the ratio of the amount of phosphorus (ppm) transferred from ash-free dialkyl dithiophosphate to the fluid and the amount of nitrogen (ppm) transferred from tolyltriazole corrosion inhibitor to the fluid (EP Phos + CI nitrogen) to the TBN coefficient is about 70,000 or less, and the TBN coefficient is the TBN (ASTM D2896) transferred to the fluid by the detergent divided by the amount of metal (ppm) transferred from the detergent to the fluid (TBN/Det metal) and/or; the sulfonate detergent is calcium sulfonate and provides about 30 to about 600 ppm of calcium to the motor lubricating fluid.
  11. A method according to claim 8, wherein a useful phosphorus anti-wear additive comprising an ashless dialkyl dithiophosphate is prepared by a process comprising the steps of: (a) reacting an organic hydroxy compound with a phosphorus pentasulfide to form a reaction product; and (b) further reacting the reaction product with an unsaturated carboxylic acid to form a useful phosphorus anti-wear additive comprising an ashless dialkyl dithiophosphate.
  12. In paragraph 8, the ashless dialkyl dithiophosphate is a compound of formula I, or a salt thereof: (Chemical Formula IIa) (wherein R4 and R5 are independently C1 to C10 linear or branched alkyl groups, and R6 is -H or -CH3 ) and/or; the ashless dialkyl dithiophosphate comprises 3-[[bis(2-methylpropoxy)phosphinothioil]thio]-2-methylpropanoic acid.
  13. A method according to claim 8, wherein the succinimide dispersant is post-treated with a phosphorus-containing compound and/or a boron-containing compound; and the succinimide dispersant delivers about 20 to about 100 ppm of phosphorus and about 5 to about 50 ppm of boron to the motor lubricating fluid.
  14. In claim 8, the sulfonate detergent is provided in an amount that imparts about 0.2 to about 1.6 TBN.
  15. In paragraph 8, the method wherein the motor lubricating fluid contains less than about 300 ppm of sulfur.

Description

Lubricating Fluid for an Electric Motor The present invention relates to a lubricating fluid for an electric motor system and a method of using the lubricating fluid. In particular, the disclosed method and composition relate to a lubricating fluid suitable for electric or hybrid-electric vehicles, comprising a tolyltriazole corrosion inhibitor, an ash-free dialkyl dithiophosphate, and a detergent that achieves copper corrosion and extreme pressure performance. The main challenge in developing electric vehicle powertrain lubricants is to achieve acceptable extreme pressure performance while minimizing copper leaching for compatibility with the electric components of the electric vehicle powertrain. Tolyltriazole compounds (e.g., methyl-benzotriazole) are effective metal deactivators that inhibit copper leaching into lubricants, but they have been found to have a negative effect on the performance of certain extreme pressure additives. For example, when tolyltriazole is combined with an ash-free dialkyl dithiophosphate extreme pressure additive in electric vehicle powertrain lubricants, the failure load stage (FLS) of FZG performance is lowered (e.g., CEC L-84-02 A10/16.6R/120 scuffing test). If tolyltriazole is not present in the composition, FZG FLS is improved, but copper leaching also increases. In one embodiment, an electric motor lubricating fluid suitable for electric or hybrid-electric vehicles is described herein. In one aspect of the present embodiment, the electric motor lubricating fluid comprises one or more base oils of lubricating viscosity; at least about 1 ppm of nitrogen provided by a tolyltriazole corrosion inhibitor; a useful phosphorus anti-wear additive comprising an ashless dialkyl dithiophosphate providing about 40 ppm to about 150 ppm of phosphorus and about 85 ppm to about 315 ppm of sulfur to the electric motor lubricating fluid; a succinimide dispersant derived from a hydrocarbyl-substituted dicarboxylic acid or anhydride reacted with a polyalkylene polyamine having one or more primary or secondary amines—wherein one or more primary or secondary amines are post-treated with a capping agent—; and an amount of a sulfonate detergent imparting about 0.02 to about 1.9 TBN (ASTM D2896) to the electric motor lubricating fluid; The electric motor lubricating fluid contains less than about 500 ppm of sulfur and at least about 70 ppm of phosphorus. In other approaches or embodiments, the motor lubricating fluid of the preceding paragraph may include other features or embodiments in any combination. Such other features or embodiments may include one or more of the following: the tolyltriazole corrosion inhibitor comprises methyl-1H-benzotriazole and/or; the ratio of the amount of phosphorus (ppm) transferred from ash-free dialkyl dithiophosphate to the fluid and the amount of nitrogen (ppm) transferred from the tolyltriazole corrosion inhibitor to the fluid (EP Phos + CI Nitrogen) to the TBN coefficient is about 70,000 or less, and the TBN coefficient is the TBN (ASTM D2896) transferred to the fluid by the detergent divided by the amount of metal (ppm) transferred from the detergent to the fluid (TBN/Det Metal) and/or; the sulfonate detergent is calcium sulfonate and provides about 30 to about 600 ppm of calcium to the motor lubricating fluid and/or; A useful phosphorus anti-wear additive comprising an ashless dialkyl dithiophosphate is prepared by a process comprising the steps of: (a) reacting an organic hydroxy compound with a phosphorus pentasulfide to form a reaction product; and (b) further reacting the reaction product with an unsaturated carboxylic acid to form a useful phosphorus anti-wear additive comprising an ashless dialkyl dithiophosphate; and/or; the ashless dialkyl dithiophosphate is a compound of Formula I, or a salt thereof: (Chemical Formula IIa) (wherein R4 and R5 are independently C1 to C10 linear or branched alkyl groups, and R6 is -H or -CH3 ) comprising/or; the ashless dialkyl dithiophosphate comprises 3-[[bis(2-methylpropoxy)phosphinothioil]thio]-2-methyl-propanoic acid; the succinimide dispersant is post-treated with a phosphorus-containing compound and/or a boron-containing compound; the succinimide dispersant delivers about 20 to about 100 ppm of phosphorus and about 5 to about 50 ppm of boron to the motor lubricating fluid and/or; the sulfonate detergent is provided in an amount imparting about 0.2 to about 0.6 TBN and/or; the motor lubricating fluid exhibits copper leaching of about 30 ppm or less according to ASTM D130; The motor lubricating fluid has a failure load stage rating of 8 or higher in the ASTM D5182 FZG A10/16.6R/120 test; or the motor lubricating fluid contains less than about 300 ppm of sulfur. In another approach or embodiment, a method for lubricating a driveline component including an electric motor is described herein. In an aspect of such an approach or embodiment, the method comprises the step of lubricating the driveline component with an e