COLOR-STABLE TRANSMISSION FLUID COMPOSITIONS

• US 20170275554A1
• Filed: 03/22/2016
• Published: 09/28/2017
• Est. Priority Date: 03/22/2016
• Status: Active Grant

• Current Assignee: Afton Chemical Corporation
• Original Assignee: Afton Chemical Corporation
• Inventors: Thalen, Lisa K.
• Granted Patent: US 9,816,044 B2
• Time in Patent Office: Days
• CPC Class Codes: C10M 135/36 the ring containing sulfur and carbon with nitrogen or oxygen
• CPC Class Codes: C10M 2203/1025 used as base material
• CPC Class Codes: C10M 2215/086 Imides
• CPC Class Codes: C10M 2215/28 Amides; Imides
• CPC Class Codes: C10M 2219/106 Thiadiazoles
• CPC Class Codes: C10N 2020/02 Viscosity; Viscosity index
• CPC Class Codes: C10N 2030/06 Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure
• CPC Class Codes: C10N 2030/20 Colour, e.g. dyes
• CPC Class Codes: C10N 2030/42 Phosphor free or low phosphor content compositions
• CPC Class Codes: C10N 2030/43 Sulfur free or low sulfur content compositions
• CPC Class Codes: C10N 2030/44 Boron free or low content boron compositions
• CPC Class Codes: C10N 2030/45 Ash-less or low ash content
• CPC Class Codes: C10N 2040/04 Oil-bath; Gear-boxes; Automatic transmissions; Traction drives
• CPC Class Codes: C10N 2040/042 for automatic transmissions
• CPC Class Codes: C10N 2070/02 Concentrating of additives

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; R¹ is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and R² 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.

Claims

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);

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 R¹ 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 R² is a hydrocarbyl group having 5-15 carbon atoms.

7. The transmission fluid composition of claim 6, wherein n is 2 and R² is a hydrocarbyl group having 8-12 carbon atoms.

8. The transmission fluid composition of claim 7, wherein n is 2 and R² is a hydrocarbyl group having 8-12 carbon atoms and R¹ is a methyl group.

9. The transmission fluid composition of claim 1, having a change in color absorption Δ

L* of negative 12 to 0, wherein Δ

L* is measured with a calorimeter at 150°

C. for 72 hours, at a content of at least 0.15 wt. % of the at least one thiadiazole compound; and

wherein Δ

L* is measured by the formula Δ

L*=L*_{aged fluid}−

L*_{fresh fluid}.

10. The transmission fluid composition of claim 1, having a change in color absorption Δ

L* of negative 11 to negative 0.5, wherein Δ

L* is measured with a calorimeter at 150°

C. for 72 hours, at a content of at least 0.15 wt. % of the at least one thiadiazole compound; and

wherein Δ

L* is measured by the formula Δ

L*=L*_{aged fluid}−

L*_{fresh fluid}.

11. The transmission fluid composition of claim 1, having a change in color absorption Δ

L* of negative 10 to negative 1, wherein Δ

L* is measured with a calorimeter at 150°

C. for 72 hours, at a content of at least 0.15 wt. % of the at least one thiadiazole compound; and

wherein Δ

L* is measured by the formula Δ

L*=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 95wt % 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.

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 1-5;

R¹ is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and

R² is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms.

24. 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, R¹ is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms;

and R² is hydrogen or a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms.

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):

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.

25. The transmission fluid composition as claimed in claim 21 wherein the additive composition comprises at least one compound of the Formula (I) wherein n is 1-5;

R¹ is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and

R² is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms.

26. The transmission fluid composition as claimed in claim 21 wherein the additive composition comprises at least one compound of the Formula (I) wherein n is 2-5, R¹ is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms;

and R² is hydrogen or a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms.