Color-stable transmission fluid compositions

Patent metadata

Field	Value
Publication number	US-9816044-B2
Application number	US-201615077554-A
Country	US
Kind code	B2
Filing date	Mar 22, 2016
Priority date	Mar 22, 2016
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

The present disclosure describes transmission fluid compositions, additive packages, and methods for lubricating a transmission, particularly transmission fluid compositions having color stability that are able to meet or exceed vehicle transmission fluid specifications for different makes of vehicles. The transmission fluid composition contains a base oil and an additive composition having at least one thiadiazole compound the selected from compounds of the Formulas (I)-(II):

wherein n is 1-5; R 1 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and R 2 is a hydrogen or is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms, wherein the transmission fluid composition is adapted for use in a transmission.

First claim

I claim:

1. A transmission fluid composition comprising
about 50% to about 99% by weight of a base oil, based on the total weight of the transmission fluid composition and an additive composition comprising one of:
(a) a reaction product of thiadiazole of one of the formulae (III) and (IV):

wherein R 1 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and a thiol of the formula R 3 —SH, wherein R 3 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms, and optionally an additional sulfur source;
(b) at least one compound of the Formula (I):

wherein n is 2-5, R 1 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and R 2 is hydrogen or a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and
(c) at least one compound of the Formula (II):

wherein n is 1-5, R 1 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and R 2 is hydrogen or a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and the transmission fluid composition is adapted for use in a transmission.

2. The transmission fluid composition as claimed in claim 1 wherein the additive composition comprises at least one compound of the Formula (I).

3. The transmission fluid composition as claimed in claim 1 wherein the additive composition comprises at least one compound of the Formula (II).

4. The transmission fluid composition as claimed in claim 1 , wherein the additive composition comprises at least one compound of the Formula (I) and at least one compound of the Formula (II).

5. The transmission fluid composition of claim 1 , wherein R 1 is an alkyl group having 1-10 carbon atoms and n is 2.

6. The transmission fluid composition of claim 5 , wherein n is 2 and R 2 is a hydrocarbyl group having 5-15 carbon atoms.

7. The transmission fluid composition of claim 6 , wherein n is 2 and R 2 is a hydrocarbyl group having 8-12 carbon atoms.

8. The transmission fluid composition of claim 7 , wherein n is 2 and R 2 is a hydrocarbyl group having 8-12 carbon atoms and R 1 is a methyl group.

9. The transmission fluid composition of claim 1 , having a change in color absorption ΔL* of negative 12 to 0, wherein ΔL* is measured with a spectrophotometer at 150° C. for 72 hours, at a content of at least 0.15 wt. % of the at least one thiadiazole compound; and wherein ΔL* is measured by the formula ΔL*=L* aged fluid −L* fresh fluid .

10. The transmission fluid composition of claim 1 , having a change in color absorption ΔL* of negative 11 to negative 0.5, wherein ΔL* is measured with a spectrophotometer at 150° C. for 72 hours, at a content of at least 0.15 wt. % of the at least one thiadiazole compound; and wherein ΔL* is measured by the formula ΔL*=L* aged fluid −L* fresh fluid .

11. The transmission fluid composition of claim 1 , having a change in color absorption ΔL* of negative 10 to negative 1, wherein ΔL* is measured with a spectrophotometer at 150° C. for 72 hours, at a content of at least 0.15 wt. % of the at least one thiadiazole compound; and wherein ΔL* is measured by the formula ΔL*=L* aged fluid −L* fresh fluid .

12. The transmission fluid composition of claim 1 , wherein the base oil comprises from about 70 wt. % to about 95 wt % of the total weight of the transmission fluid composition.

13. The transmission fluid composition of claim 1 , wherein the sulfur content delivered to the transmission fluid composition by the at least one thiadiazole compound of the Formulas (I)-(II) is from about 50 to about 10,000 ppm.

14. The transmission fluid composition of claim 1 , wherein the sulfur content delivered to the transmission fluid composition by the at least one thiadiazole compound of the Formulas (I)-(II) is from about 300 to about 2,500 ppm.

15. The transmission fluid composition of claim 1 , wherein the sulfur content delivered to the transmission fluid composition by the at least one thiadiazole compound of the Formulas (I)-(II) is from about 400 to about 2,000 ppm.

16. The transmission fluid composition of claim 1 , wherein the total sulfur content of the transmission fluid composition is from about 50 to about 12,000 ppm.

17. An automatic transmission containing the transmission fluid composition of claim 1 .

18. The automatic transmission of claim 17 , wherein the automatic transmission is selected from the group consisting of a continuously variable transmission, step type transmission or double clutch transmission.

19. A method of operating a transmission comprising a step of operating the transmission lubricated with the transmission fluid composition of claim 1 .

20. A vehicle comprising an engine and a transmission, the transmission including the transmission fluid composition of claim 1 .

21. An additive composition for a transmission fluid, the additive composition comprising at least one color stable extreme pressure performance improver selected from one of
(a) a reaction product of thiadiazole of one of the formulae (III) and (IV):

wherein R 1 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and a thiol of the formula R 3 —SH, wherein R 3 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms, and optionally an additional sulfur source;
(b) at least one compound of the Formula (I):

wherein n is 2-5, R 1 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and R 2 is hydrogen or a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and
(c) at least one compound of the Formula (II):

wherein n is 1-5, R 1 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and R 2 is hydrogen or a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms.

22. The additive composition for a transmission fluid of claim 21 , wherein the additive improves extreme pressure characteristics while maintaining color stability of a transmission fluid.

23. The transmission fluid composition as claimed in claim 1 wherein the additive composition comprises at least one compound of the Formula (I) wherein n is 2-5, R 1 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and R 2 is hydrogen or a substituted hydrocarbyl group having 1-100 carbon atoms.

24. The additive composition for a transmission fluid as claimed in claim 21 wherein the additive composition comprises at least one compound of the Formula (I) wherein n is 2-5, R 1 is a substituted hydrocarbyl group having 1-100 carbon atoms; and R 2 is hydrogen or a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms.

Assignees

• Afton Chemical Corp

Inventors

• Thalen Lisa K

Classifications

• C10N2030/43

  Sulfur free or low sulfur content compositions · CPC title

• C10N2030/06

  Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure · CPC title

• C10M2215/086

  Imides [having hydrocarbon substituents containing less than thirty carbon atoms] · CPC title

• C10N2030/20

  Colour, e.g. dyes · CPC title

• C10M135/36 Primary

  the ring containing sulfur and carbon with nitrogen or oxygen · CPC title