JPH08176571A - Fluid composition for traction drive - Google Patents

Abstract

PURPOSE: To obtain the subject fluid, consisting essentially of a specific dicyclohexylalkane and a specified octahydroindan skeletal compound, improved in the traction coefficient and causing extremely slight deterioration thereof, especially at high temperatures and suitable as an automotive speed change gear, etc. CONSTITUTION: This fluid consists essentially of (A) a compound of formula I (R1 to R6 are each H or a 1-3C alkyl) such as 2,4-dicyclohexyl-2- dimethylpentane or a compound of formula II (R7 to R10 ) are each R1 ) such as 2,3-dicyclohexylbutane and (B) a compound of formula III (R11 to R16 are each R1 ) such as 1,3-dimethyl-1-cyclohexyl-3-(2-cyclohexyl-2-methylpropyl) octahydroindan. The fluid contains 5-50wt.% component (B).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to traction drive fluid compositions. More specifically, the present invention relates to a traction drive fluid composition having a high traction coefficient in a wide temperature range, which is suitable for a traction drive having a large torque capacity such as an automobile transmission and severe operating conditions.

[0002]

2. Description of the Related Art A traction drive device uses a rolling-sliding frictional force resulting from a resistance force against shearing caused by a fluid oil film sandwiched between a cylindrical or conical rotating body losing its fluidity and hardening due to high pressure. It is a transmission device. This traction drive device has been recently researched for higher performance or smaller size and lighter weight, especially for automobile applications, and a high performance traction drive fluid is required.

As a fluid for a traction drive, it has been proposed to use a special synthetic base oil having a high traction coefficient, which is a measure of power transmission capacity, and is disclosed in JP-A-62-16989.
7, JP-A-62-177098, JP-A-63-2307
94, Japanese Patent Publication No. 53-36105, etc.

[0004]

However, a material having a sufficiently high traction coefficient over a wide temperature range has not yet been known. For example, 1,3-dicyclohexyl-3-methylbutane having two cyclohexane rings has a high traction coefficient near 30 ° C., but the traction coefficient remarkably decreases with increasing temperature. Further, in order to reduce the decrease in the traction coefficient at this high temperature, JP-A-62-16989 is used.
In No. 7, 1,3,5-tricyclohexyl-5-methylhexane having three cyclohexane rings was added to slightly improve the decrease in traction coefficient at high temperature, but the traction coefficient at low temperature was lower than that before addition. There are such drawbacks. That is, there is a need to develop a traction drive fluid that has a high traction coefficient at low temperatures and a small decrease in traction coefficient even at high temperatures (around 120 ° C.).

[0005]

Therefore, the present inventor has conducted intensive studies to develop a fluid composition for a traction drive having a high traction coefficient over a wide temperature range, and as a result, an octahydroindane skeleton and two or more octane hydroindane skeletons have been developed. It was found that when the compound having a cyclohexyl group is mixed with the compound having two cyclohexane rings described above, the decrease in the traction coefficient at high temperature is reduced, and the present invention has been completed.

That is, the gist of the present invention is (A)

Embedded image Or

[Chemical 6] And (B)

[Chemical 7] (In the above formula, R _{1 to} R ₁₆ may be the same or different and each is hydrogen or an alkyl group having 1 to 3 carbon atoms) as a main component, and 5 to 50% by weight of (B) is contained. And a fluid composition for a traction drive.

The traction drive fluid composition of the present invention is a compound in which the main chain which is the component (A) is a substituted or unsubstituted alkylene group having 3 carbon atoms, and both ends thereof are sealed with a cyclohexyl group, Alternatively, a compound whose main chain is a substituted or unsubstituted alkylene group having 2 carbon atoms and whose both ends are sealed with a cyclohexyl group, and (B)
The main component is a compound having an octahydroindane skeleton and two cyclohexyl groups.

A first example of the component (A) is represented by the general formula A ₁ .

Embedded image (In the formula, R _{1 to} R ₆ may be the same or different and each is hydrogen or an alkyl group having 1 to 3 carbon atoms, that is, a methyl group, an ethyl group, an n-propyl group or an i-propyl group.)

Specific examples thereof include 2,4-dicyclohexyl-2-methylpentane, 2,4-dicyclohexyl-2-methylbutane and 2,4-dicyclohexyl-
2,4-dimethylpentane and the like can be mentioned.

A second example of the component (A) is represented by the general formula A ₂ .

[Chemical 9] (In the formula, R _{7 to} R ₁₀ may be the same or different and each is hydrogen or an alkyl group having 1 to 3 carbon atoms, that is, a methyl group, an ethyl group, an n-propyl group or an i-propyl group.)

Specific examples thereof include 1,2-dicyclohexylethane, 1,2-dicyclohexylpropane,
2,3-dicyclohexylbutane, 1,2-dicyclohexyl-2-methylpropane, 2,3-dicyclohexyl-2,3-dimethylbutane and the like can be mentioned.

It is preferable that at least one of R _{1 to} R ₆ is the above alkyl group, and it is more preferable that two or more are the above alkyl groups. Further, it is preferable that at least one of R _{7 to} R ₁₀ is the above alkyl group,
It is more preferable that two or more are the above alkyl groups. Particularly in both the first and second examples, it is preferable that the carbon connected to the cyclohexyl group has the above alkyl group. Further, as the alkyl group, a methyl group is preferable from the viewpoint of ease of production and cost.

The component (B) is represented by the general formula B.

[Chemical 10] (In the formula, R _{11 to} R ₁₆ may be the same or different and each is hydrogen or an alkyl group having 1 to 3 carbon atoms, that is, a methyl group, an ethyl group, an n-propyl group or an i-propyl group.)

It is preferable that at least one of R _{11 to} R ₁₆ is the above alkyl group, and it is more preferable that two or more are the above alkyl groups. In particular, it is preferable that the carbon connected to the cyclohexyl group has the above alkyl group. Further, as the alkyl group, a methyl group is preferable from the viewpoint of ease of production and cost.

Specific examples thereof include 1,3-dimethyl-
1-cyclohexyl-3- (2-cyclohexyl-2-
Methylpropyl) octahydroindane, 1-cyclohexyl-3- (2-cyclohexylethyl) octahydroindane, 1-methyl-1-cyclohexyl-3-
(2-cyclohexylethyl) octahydroindane,
1,3-dimethyl-1-cyclohexyl-3- (2-cyclohexylethyl) octahydroindane, 1,3-
Dimethyl-1-cyclohexyl-3- (2-cyclohexylpropyl) octahydroindane and the like can be mentioned.

Further, the fluid composition of the present invention comprises, as an optional component, a compound having a main chain of a substituted or unsubstituted alkylene group having 5 carbon atoms and having three cyclohexyl groups at both ends and a central carbon atom. It may be contained as the component (C). The component (C) is represented by the following general formula C.

[Chemical 11] (In the formula, R _{17 to} R ₂₅ may be the same or different and each is hydrogen or an alkyl group having 1 to 3 carbon atoms, that is, a methyl group, an ethyl group, an n-propyl group or an i-propyl group.)

It is preferable that at least two of R _{17 to} R ₂₅ are the above alkyl groups, and it is more preferable that three or more are the above alkyl groups. In particular, it is preferable that the carbon connected to the cyclohexyl group has the above alkyl group. Further, as the alkyl group, a methyl group is preferable from the viewpoint of ease of production and cost.

Specific examples of the component (C) are 2, 4, 6
-Tricyclohexyl-2,4-dimethylheptane,
2,4,6-tricyclohexyl-2-methylhexane, 2,4,6-tricyclohexyl-2,4,6-trimethylheptane and the like can be mentioned.

The method for producing the component (A), the component (B) and the optional component (C) used in the present invention is not particularly limited, and any suitable method can be adopted. An example of the production method of the component (A) is to dimerize and hydrogenate an α-alkylstyrene such as α-methylstyrene or styrene, and an example of the production method of the component (C) is an α-methylstyrene. Such an α-alkylstyrene or styrene is trimerized and hydrogenated, and one example of the method for producing the component (B) is α
Α-Alkylstyrene such as methylstyrene or styrene is trimerized, that is, the intermediate of the component (C) is cyclized and hydrogenated. The above-mentioned dimerization, trimerization, cyclization, and hydrogenation methods are not particularly limited and can be appropriately performed by known methods.

For example, the dimerization of α-methylstyrene or the like is carried out by using a heteropolyacid catalyst such as 12-molybdophosphoric acid or 12-tungstophosphoric acid in the absence of a solvent at 80-14.
Method at 0 ° C. (Japanese Patent Application No. 6-60251), method using the above heteropolyacid in the coexistence of water (Japanese Patent Application No. 6-60252), or Al ₂ O ₃ —TiO _2.
2 Method using a (1: 1) catalyst [(Chem. Lett., 13
(1980)] or a method using activated clay-ethylene glycol (JP-A-62-169897).

Further, acid clay, mineral acids such as sulfuric acid, hydrochloric acid and hydrogen fluoride, organic acids such as p-toluenesulfonic acid and triflic acid, aluminum chloride, ferric chloride and ferric chloride.
A method in which a Lewis acid such as tin, boron trifluoride, boron bromide, aluminum bromide, gallium chloride or gallium bromide, or a solid acid such as zeolite, silica, alumina, silica-alumina or cation exchange resin is used as a catalyst. There is also.

The hydrogenation can also be carried out in the presence of a catalyst, if necessary, with the addition of a solvent. As a catalyst,
Nickel, ruthenium, palladium, platinum, rhodium,
Iridium, copper, chromium, molybdenum, cobalt, containing one or more metals such as tungsten, it is possible to use what is known as a hydrogenation catalyst, as the solvent,
Examples thereof include low boiling point saturated hydrocarbons such as cyclohexane, n-hexane, cyclopentane, n-pentane, and n-heptane.

The trimerization of α-methylstyrene and the like is carried out at 30-80 ° C. in the absence of solvent using the above-mentioned heteropolyacid as a catalyst.
(Japanese Patent Application No. 6-173497). In the dimerization in the system using the above Al ₂ O ₃ —TiO ₂ (1: 1) catalyst, a trimer produced as a by-product can also be used.

The component (B) of the present invention is obtained by cyclizing the trimer obtained by the above-mentioned method by heating at about 50 to 120 ° C. using an acid catalyst such as sulfuric acid, heteropolyacid or aluminum chloride. It can be obtained by forming an indene ring and hydrogenating it. This hydrogenation can be easily performed by the same means as described above.

In the present invention, the component (B) is 5 to 50% by weight, preferably 5 to 40% by weight, particularly preferably 5 to 35% by weight, based on the fluid composition for traction drive. If it is less than this, the effect of preventing the reduction of the traction coefficient at high temperature, which is the effect of blending the component (B), does not appear, and if it is more than 50 wt%, the viscosity becomes high and the energy loss accompanying stirring becomes large, which is preferable. Absent.

In preparing the component (B),
3 such as α-methylstyrene which was not converted to the component (B)
The monomer (B) may be contained in an amount of about 0 to 95% by weight, but the unconverted component is the component (C) which is an optional component of the present invention. ),
The component (B) may be appropriately added and used, or if the conversion rate to the component (B) is low and the effect of the component (B) does not appear as it is, the concentration of the component (B) is increased by distillation. You may use it.

In addition, when α-methylstyrene and the like are polymerized using an acid catalyst, dimers (component (A)) and 3
In addition to the monomer (component (C)), a considerable amount of component (B) may also be produced. In this case, the mixture may be hydrogenated and used as it is, or if the concentration of the component (B) is low, the concentration may be increased by distillation before use. However, the higher the content of the octahydroindane compound in the component (B), the better.

The proportion of the component (C) which is an optional component of the present invention is 0 in the fluid composition for traction drive of the present invention.
-30% by weight is suitable, and preferably 0-20.
It is in the range of% by weight. When the proportion of the component (C) exceeds 30% by weight, the conversion effect of the component (B) of the present invention is diluted to that extent, and the effect of preventing the reduction of the traction coefficient at high temperature is reduced.

The fluid composition for traction drive of the present invention can be prepared by adding various additives such as antioxidants and antiwear agents in an amount of about 0.05 to 10% by weight, depending on the application. .

[0030]

The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

The traction drive fluids obtained in Examples and Comparative Examples were evaluated by the following methods. Traction coefficient: Using a four-cylinder friction tester (roller diameter 4 cm, thickness 1 cm), drive shaft rotation speed 2,000 rpm (4.19 m / s), slip rate 5%, maximum Hertz pressure 1 Apply a normal load so that it becomes 2 GPa,
It was expressed as the ratio of the transmitted tangential force to the normal load measured at the test oil temperature of 30 ° C to 120 ° C.

Production Example 1 5 kg of α-methylstyrene was added to a 10 l glass reaction vessel.
12-Tungstophosphoric acid (Kanto Chemical Co., Inc.) 100 g
Put in, heat at 50 ° C. for 1 hour, stir to react,
The reaction vessel was cooled in a 20 ° C. water bath and the catalyst was removed by filtration. The filtrate is distilled under reduced pressure to give a boiling point of 160 to 16
5 ° C / 2mmHg fraction (fraction) 2500g and boiling point 18
5 to 190 ° C./2 mmHg fraction (distillate) of 1800 g was obtained.

Fraction 2500 in a 10 l autoclave
g and cyclohexane 2500 g, hydrogenation catalyst N-1
50 g of 13 (JGC Corporation) was added and the mixture was sealed. Hydrogen pressure 60K
Hydrogenation was carried out at g / cm ² and a reaction temperature of 200 ° C. for 4 hours. After cooling, the catalyst was removed by filtration, cyclohexane was distilled off by a rotary evaporator, and 2,4-dicyclohexyl-2-methylpentane [(A) component] 25
50 g was obtained.

A 3 l glass reaction vessel was charged with 900 g of the distillate and 18 g of 12-tungstophosphoric acid and heated and stirred at 120 ° C. for 15 minutes. The reaction vessel was allowed to cool, further cooled with water, and the catalyst was removed by filtration. This filtrate was placed in a 3 l autoclave, and 900 g of cyclohexane and N-
18 g of 113 hydrogenation catalyst were added and sealed. Hydrogen pressure 60
After reacting at 200 ° C. for 4 hours at Kg / cm ² , the mixture was allowed to cool. After removing the catalyst by filtration, the filtrate was evaporated to remove cyclohexane, and 1,3-dimethyl-1-cyclohexyl-3- (2-cyclohexyl-2) was removed.
950 g of (methylpropyl) octahydroindane [component (B)] was obtained.

In a 3 l autoclave, 900 g of distillate and 900 g of cyclohexane, N-113 hydrogenation catalyst 1
8g was put and sealed. Hydrogen pressure 60 kg / cm ² , 20
After reacting at 0 ° C. for 4 hours, the mixture was allowed to cool. After removing the catalyst by filtration, the filtrate was evaporated to remove cyclohexane, and 2,4,6-tricyclohexyl-2,4
-950 g of dimethylheptane [(component C)] was obtained.

Production Example 2 2300 g of anhydrous cumene, 40 g of sodium metal and 11 parts of isopropyl alcohol were placed in a 5 l glass flask.
Then, 650 g of styrene was added dropwise over 3 hours with vigorous stirring, and the mixture was stirred for 1 hour to complete the reaction. After the stirring was stopped and the mixture was allowed to stand and cooled, the oil layer was taken out, 200 g of ethanol was added thereto, and the mixture was washed 3 times with 2 L of 5N hydrochloric acid aqueous solution and 2 L of saturated saline solution.
After drying over anhydrous sodium sulfate, the unreacted cumene was distilled off by applying a rotary evaporator, and then vacuum distillation was carried out to obtain a boiling point of 115 to 125 ° C / 0.13 mmHg fraction (distillate) of 1100 g and a boiling point of 155 to 165 ° C / 0.13.
450 g of mmHg fraction (fraction) was obtained. As a result of analyzing each fraction, the fraction was 1,3,5-triphenyl-5
-Methylhexane, the fraction is 1,3-diphenyl-3-
It was methyl butane.

450 g of the fraction was placed in a 10-liter autoclave, 4500 g of cyclohexane and 45 g of a Pd / C hydrogenation catalyst (5 wt% Pd supported; Wako Pure Chemical Industries, Ltd.) were placed, and the autoclave was closed. 180 at hydrogen pressure of 60 kg / cm ²
Hydrogenation was performed at 8 ° C for 8 hours, and the mixture was allowed to cool to room temperature. The catalyst was filtered off, cyclohexane was distilled off by a rotary evaporator, and the product was analyzed. As a result, it was 1,3,5-tricyclohexyl-5-methylhexane (component). Also,
When hydrogenation was performed on the distillate in the same manner, 1,3-
Dicyclohexyl-3-methylbutane was obtained (component).

Example 1 The components (A), (B) and (C) obtained in Production Example 1 were mixed at a weight ratio of (A) / (B) / (C) = 7/1/2. The mixture was mixed to obtain a traction drive fluid composition. The viscosity of this fluid composition is (40 ° C.) 102.3 cSt,
(100 ° C.) was 8.233 cSt. The traction coefficient is shown in FIG.

Comparative Example 1 100% of the component obtained in Preparation Example 2 was tested as a traction drive fluid composition. The viscosity of this fluid composition is (40 ° C.) 16.47 cSt, (100 ° C.) 3.208.
It was cSt. The traction coefficient is shown in FIG.

Comparative Example 2 The components and the components obtained in Production Example 2 were mixed in a weight ratio of 7
The mixture was mixed at a ratio of / 3 to obtain a traction drive fluid composition. The viscosity of this liquid is (40 ° C) 44.65c
St, (100 ° C.) was 4.973 cSt. The traction coefficient is shown in FIG.

Comparative Example 3 The components (A) and (C) obtained in Production Example 1 were replaced with (A) /
(C) The mixture was mixed at a weight ratio of 7/3 to obtain a traction drive fluid composition. The viscosity of this liquid is (40
C) 103.9 cSt, (100 C) 8.142 cSt
Met. The traction coefficient is shown in FIG.

[0042]

Effects of the Invention By adding an octahydroindane derivative having a small change in molecular structure at high temperature to a fluid composition for traction drive, a decrease in traction coefficient at high temperature becomes extremely small.

[Brief description of drawings]

FIG. 1 shows Example 1, Comparative Example 1, Comparative Example 2 and Comparative Example 3.
3 is a graph showing the relationship between the temperature and the traction coefficient of the traction drive fluid composition of FIG.

Claims (2)

[Claims] 1. (A) embedded image Or [Chemical 2] And (B) (In the above formula, R _{1 to} R ₁₆ may be the same or different and each is hydrogen or an alkyl group having 1 to 3 carbon atoms) as a main component, and 5 to 50% by weight of (B) is contained. A fluid composition for a traction drive, comprising: 2. (In the formula, R _{17 to} R ₂₅ may be the same or different and each is hydrogen or an alkyl group having 1 to 3 carbon atoms.)
The traction drive fluid composition of claim 1, further comprising: