JPH0563519B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a traction drive fluid;
More specifically, the present invention relates to a traction drive fluid that has low viscosity and exhibits excellent traction performance over a wide temperature range from low to high temperatures.

[Problems to be solved by conventional technology and invention]

In general, traction drive fluid is a fluid used in traction drive devices (friction drive devices using rolling and sliding contact), such as continuously variable transmissions for automobiles, continuously variable transmissions for industrial use, and hydraulic equipment, and has a high traction coefficient. Stability against heat and oxidation, economic efficiency, etc. are required.

In recent years, research has been focused on reducing the size and weight of traction drive devices, mainly for automotive applications, and along with this, the traction drive fluid used in these traction drive devices has also been developed to reduce the size and weight of traction drive devices, which can be used under various harsh conditions. Stably high performance over a wide temperature range from low to high temperatures (approximately -30 to 140℃) (high traction coefficient, low viscosity, excellent thermal and oxidation stability) They are required to be able to demonstrate their abilities (e.g.,

However, until now, Tokuko Publication No. 46-338,
Various traction drive fluids have been developed, including Japanese Patent Publication No. 46-339, but none of them can satisfy the above-mentioned required characteristics.
Various problems arose. For example, a compound that exhibits a high traction coefficient at high temperatures has a high viscosity and a large stirring loss, resulting in low transmission efficiency and also has problems in low-temperature startability. On the other hand, compounds with low viscosity and excellent transmission efficiency have a low traction coefficient at high temperatures, and their viscosity decreases too much at high temperatures, causing problems with the lubrication of traction transmission devices.

In order to solve these problems, the use of an ester compound having a bicyclo[2.2.1]heptane ring as a traction drive fluid is being considered (Japanese Patent Publication No. 44918/1983).
This has a major problem in that the traction coefficient at high temperatures is insufficient. In addition, ester compounds have various problems such as extremely poor oxidation stability, coloring, and emitting an extremely bad odor at high temperatures. Furthermore, JP-A No. 62-148597 describes hydrogenated products of the reaction products of aromatic compounds and dihydrodicyclopentadiene, but these also have sufficiently satisfactory traction coefficients at high temperatures. The problem is that it is not.

[Means for solving problems]

The inventors of the present invention therefore conducted extensive research in order to solve the problems of the prior art described above and to develop a traction drive fluid that has low viscosity and excellent performance over a wide temperature range.

As a result, the inventors discovered that a bicyclo[2.2.1]heptane derivative having a specific structure has excellent overall performance as a traction drive fluid from low to high temperatures, leading to the completion of the present invention.

That is, the present invention has the following general formula: [In the formula, R ¹ to ^{R 12} each represent a hydrogen atom, a methyl group, an ethyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a trimethylcyclohexyl group, a decalyl group, or a methyldecalyl group. However, at least one of R ¹ to ^{R 12} is a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a trimethylcyclohexyl group, a decalyl group, or a methyldecalyl group. ] Bicyclo having 16 to 22 carbon atoms [2.2.1]
The present invention provides a traction drive fluid characterized by containing a heptane derivative.

The bicyclo[2.2.1]heptane derivative represented by the general formula [] of the present invention has substituents R 1 to R ¹ to carbon atoms constituting the bicycloheptane skeleton, respectively.
R ¹² is bonded. These substituents R ¹ to ^{R 12} are hydrogen atoms, methyl groups, ethyl groups, cyclohexyl groups, methylcyclohexyl groups, dimethylcyclohexyl groups, trimethylcyclohexyl groups,
It represents a decalyl group or a methyldecalyl group, of which at least one substituent is
The above alicyclic hydrocarbon group (ie, cyclohexyl group, methylcyclohexyl group, dimethylcyclohexyl group, trimethylcyclohexyl group, decalyl group or methyldecalyl group). Furthermore, the bicyclo[2.2.1]heptane derivative of the present invention has a total number of carbon atoms (i.e., the total number of carbon atoms of the bicycloheptane skeleton of 7 and the total number of carbon atoms of the substituents R ¹ to ^{R 12} of 9 to 15) from 16 to 22 ranges. Here, as mentioned above, at least one of the substituents R ¹ to ^{R 12} represents the above alicyclic hydrocarbon group, and two or more of the substituents may be an alicyclic hydrocarbon group. However, usually one of the substituents R ¹ to ^{R 12} represents an alicyclic hydrocarbon group. In addition, it is not necessarily specified which of these substituents R ¹ to ^{R 12} represents an alicyclic hydrocarbon group, but it is usually
It is any one of ^R1 to ^R8 . However, the bicyclo[2.2.1]heptane derivatives of the present invention are not necessarily limited to one type of compound, but include several types in which the alicyclic hydrocarbon group has a different bonding position to the bicyclo[2.2.1]heptane skeleton. It may also be a mixture of compounds.

If all of the substituents R ¹ to R ¹² are other than the above-mentioned alicyclic hydrocarbon groups, the desired traction performance will not be achieved.

The bicyclo[2.2.1]heptane derivative of the present invention may be a single compound, but it can be substituted as long as the alicyclic hydrocarbon group has a different bonding position, and as long as it satisfies the above general formula. It may be a mixture of several types of compounds having different types of groups.

The bicyclo[2.2.1]heptane derivative of the present invention is
It can be manufactured by various methods, but
Usually, it can be produced by hydrogenating a product obtained by combining bicyclo[2.2.1]heptanes and an aromatic compound by a Friedel-Crafts reaction. Here, the bicyclo[2.2.1]heptanes include camphene (d-form, d-form, dl-form),
bornylene (d-form,
dl form), γ-Fentien, δ-Fentien,
ε-Fuentien, ζ-Fuentien, borneol (d-form, dl-form), π-borneol (d-form, dl-form), ω-borneol, isoborneol (d-form, dl-form), camphuene hydrate,
α-phentyl alcohol (d-form, d-form, dl-form),
β-phentyl alcohol (d-form, d-form, dl-form),
α-Isophenthyl alcohol (d-isomer, dl-isomer, dl
), β-isophenthyl alcohol (d-isomer,
and dl-form), and mixtures thereof may also be used. Furthermore, compounds obtained by introducing various substituents into these compounds can also be used.

On the other hand, the aromatic compound to be reacted with the bicyclo[2.2.1]heptanes is bonded with the bicycloheptanes and further hydrogenated, and then the substituents R ¹ to
This is an alicyclic hydrocarbon group for ^R12 . Examples of such aromatic compounds include benzene,
Toluene, o-xylene, m-xylene, p-xylene, trimethylbenzene, ethylbenzene,
Examples include naphthalene, tetralin, and methylnaphthalene.

The reaction between the above-mentioned bicyclo[2.2.1] heptanes and aromatic compounds is carried out in the presence of a catalyst, with the addition of a solvent and a reaction regulator if necessary, and various catalysts can be used. However, in general, mineral acids such as sulfuric acid and hydrochloric acid, organic acids such as p-toluenesulfonic acid and triflic acid, heteropolyacids, and furthermore aluminum chloride, ferric chloride, stannic chloride, boron trifluoride, and trifluoride. Lewis acids such as boron oxide, aluminum bromide, gallium chloride, and gallium bromide, as well as various other catalysts commonly used as Friedel-Crafts catalysts, can be used. There is no particular restriction on the amount used, but it is usually 0.1 to
100% by weight, preferably in the range 1-20% by weight.

In the above Friedel-Crafts reaction, a solvent is not necessarily required, but it can be used to handle bicyclo[2.2.1]heptanes, aromatic compounds, and catalysts during the reaction, or to control the progress of the reaction. preferable. Such solvents include n-
Pentane, n-hexane, heptane, octane,
Most saturated hydrocarbons such as nonane, decane, cyclopentane, cyclohexane, methylcyclohexane, and decalin can be used, and mononitro compounds such as nitromethane and nitrobenzene can also be used.

In addition, the reaction regulator is used as necessary to appropriately react bicyclo[2.2.1]heptanes with aromatic compounds. Compounds are preferred. In addition, various kinds of esters such as esters such as ethyl acetate, ketones such as mesityl oxide, aldehydes such as formalin and acetaldehyde, cellosolves, and polyalkylene glycol alkyl ethers such as diethylene glycol monoethyl ether can be used. The amount of these reaction regulators to be used may be selected generally in the range of 0.1 to 100% by weight based on the above catalyst.

The Friedel-Crafts reaction is carried out in the presence of these catalysts, and the reaction conditions are generally -30
Appropriate conditions are set within the temperature range of 0°C to 180°C, preferably 0°C to 80°C, depending on the type of catalyst, additives, etc.

Next, a product in which an aromatic compound is bonded to bicyclo[2.2.1]heptane (bonded product) is hydrogenated according to the above procedure. Hydrogenation may be performed on the entire amount of the above-mentioned combined product, or may be performed by fractionating or fractionating a portion of the combined product.

This hydrogenation is also carried out in the presence of a catalyst like the Friedel-Crafts reaction, but the catalyst is a so-called hydrogenation catalyst containing one or more metals such as nickel, ruthenium, palladium, platinum, rhodium, and iridium. What is known as can be used. The amount of this catalyst added is not particularly limited, but is usually 0.1 to 100% of the above combined product.
% by weight, preferably in the range 1-10% by weight.

Also, like the Friedel-Crafts reaction, this hydrogenation reaction proceeds without a solvent, but a solvent can also be used. In that case, the types of solvent include n-pentane, n-hexane, heptane, Octane, nonane, dodecane, etc. and cyclopentane,
Most liquid saturated hydrocarbons such as cyclohexane and methylcyclohexane can be used. Furthermore, liquids such as aromatics, olefins, alcohols, ketones, and ethers can be used, but saturated hydrocarbons are particularly preferred.

The reaction temperature is usually room temperature to 300°C, preferably
The temperature is 80 to 250℃, and the reaction pressure is 200Kg/
cm ² G, preferably in the range of 40 to 150 Kg/cm ² G, and can be carried out in the same manner as general hydrogenation.

The thus produced bicyclo[2.2.1]heptane derivative represented by the general formula [] can be used by mixing with other traction drive fluids if necessary. In this case, it is desirable to adjust the content of the bicyclo[2.2.1]heptane derivative to be at least 5% by weight, preferably 30% by weight or more. Other traction drive fluids are not particularly limited, and include, for example, alkane derivatives having two or three or more cyclohexane rings, alkane derivatives having one or more decalin rings and one or more cyclohexane rings, and two decalin rings. Examples include alkane derivatives having the above, and compounds having a structure in which two or more cyclohexane rings or decalin rings are directly bonded.

Furthermore, the traction drive fluid of the present invention may optionally contain antioxidants, rust inhibitors, detergent dispersants, pour point depressants, viscosity index improvers, extreme pressure agents, anti-wear additives, and anti-fatigue agents. , antifoaming agent, oiliness improver,
Appropriate amounts of various additives such as colorants can also be used.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 A stirrer, a thermometer, a dropping funnel, and a Dimroth reflux condenser were attached to the four-necked flask in Example 1, and 500 ml of m-xylene, which served as a solvent and raw material, and 90.0 g of concentrated sulfuric acid as a catalyst were charged and stirred. Next, at 25°C, add 1 ml of a mixed solution of 200.6 g of camphuene and 50 ml of m-xylene.
The mixture was added dropwise while stirring over time. At this time, the temperature of the reaction solution was 35°C. After stirring for 20 minutes, transfer the reaction solution to a separating funnel.
The sulfuric acid layer was separated and removed. The organic layer was diluted twice with 300 ml of 10% sodium bicarbonate aqueous solution and 200 ml of saturated saline.
ml twice and dried over anhydrous magnesium sulfate. After standing overnight, the desiccant was filtered off, and the solvent and unreacted raw materials were recovered using a rotary evaporator to obtain 225 g of the remaining reaction solution. Next, this was distilled under reduced pressure to obtain a fraction 176 with a boiling point of 128-134℃/0.2mmHg.
I got g. Using gas chromatography-mass spectrometry (GC-MS) and hydrogen flame type (FID) gas chromatography (GC), this
It was found that more than 99% of the components contained 18 carbon atoms, which is camphuene added to xylene.

175 g of this fraction and 18 g of 5% by weight ruthenium/activated carbon catalyst for hydrogenation (manufactured by Nippon Engelhard Co., Ltd.)
into one autoclave and hydrogen pressure 85Kg/cm ²
G. Hydrogenation was carried out at a reaction temperature of 160°C for 7 hours. After cooling, the catalyst was filtered and analyzed, and the hydrogenation rate was found to be 99% or more. The properties of this material are shown below.

Kinematic viscosity 16.17cSt (40℃) 3.030cSt (100℃) Viscosity index -13 Specific gravity (15/4℃) 0.9240 Pour point -35.0℃ Refractive index (n ²⁰ _D ′ 1.4948 Change the traction coefficient of this material from 60℃ to 140℃
Figure 1 shows the results measured over a temperature range of .

Example 2 A stirrer, a thermometer, a dropping funnel, and a Dimroth reflux condenser were attached to the four-necked flask from Example 2 1, and 600 ml of m-xylene as a solvent and raw material and 10.3 g of anhydrous aluminum chloride as a catalyst were charged and stirred.

Next, a mixed solution of 220.7 g of camphene and 50 ml of m-xylene was added dropwise at 21° C. with stirring over a period of 2 hours. At this time, the temperature of the reaction solution was 45°C. After stirring for 30 minutes, the reaction solution was
The reaction was stopped by pouring it into ice water. Take the organic layer with a separating funnel and add 300ml of 10% hydrochloric acid twice.
It was washed twice with 300 ml of 10% aqueous sodium bicarbonate solution and twice with 200 ml of saturated brine, and dried over anhydrous magnesium sulfate.

After standing overnight, the desiccant was filtered off, and the solvent and unreacted raw materials were recovered using a rotary evaporator to obtain 343 g of the remaining reaction liquid.

Next, this is distilled under reduced pressure, with a boiling point of 119-128℃/0.2
232 g of a fraction of mmHg was obtained. GC-MS and GC
According to (FID), this product is m as in Example 1.
-It was found that more than 99% of the components contained 18 carbon atoms, which is camphuene added to xylene.

230 g of this fraction and 20 g of a nickel catalyst for hydrogenation (N-113, manufactured by JGC Chemical Co., Ltd.) were charged into one autoclave, and hydrogenation was carried out at a hydrogen pressure of 85 kg/cm ² G. and a reaction temperature of 170° C. for 4 hours. After cooling, the catalyst was filtered and analyzed, and the hydrogenation rate was found to be 99% or more.

The properties of this material are shown below.

Kinematic viscosity 15.04cSt (40℃) 2.775cSt (100℃) Viscosity index -50 Specific gravity (15/4℃) 0.9134 Pour point -32.5℃ Refractive index (n ²⁰ _D ) 1.4890 Change the traction coefficient of this material from 60℃ to 140℃
Figure 1 shows the results measured over a temperature range of .

Example 3 A stirrer, a thermometer, and a dropping funnel were attached to the four-necked flask from Example 3, and 268.3 g of naphthalene, 1020 g of carbon tetrachloride as a solvent, and 101.7 g of concentrated sulfuric acid as a catalyst were added.
g was prepared, and the mixture was kept at 4°C in an ice bath and stirred.

Next, 160.5g of camphuen and 60.4g of carbon tetrachloride.
A mixed solution of was added dropwise over a period of 4.5 hours. At this time, the temperature of the reaction solution had reached 8°C.

This reaction solution was transferred to a separating funnel, the sulfuric acid layer was removed, and the organic layer was dissolved in 10% sodium hydrogen carbonate aqueous solution 300
After washing with ml twice and twice with saturated saline, it was dried with anhydrous calcium chloride.

After standing overnight, the desiccant was filtered off, and the solvent and unreacted raw materials were recovered using a rotary evaporator to obtain 203 g of the remaining reaction liquid.

Next, this is distilled under reduced pressure to obtain a boiling point of 164-182℃/0.2
142 g of a fraction of mmHg was obtained.

GC-MS and GC (FID) revealed that more than 99% of this product consisted of a component with 20 carbon atoms, which is the addition of camphuene to naphthalene.

140 g of this fraction and 5% by weight ruthenium/activated carbon catalyst for hydrogenation (manufactured by Nippon Engelhard Co., Ltd.) 15
g into an autoclave, add 200 g of methylcyclohexane as a solvent, and hydrogen pressure of 90 Kg/cm ²
G, hydrogenation was carried out at a reaction temperature of 165°C for 6 hours.
After cooling, the catalyst was filtered off, the solvent was removed, and analysis revealed that the hydrogenation rate was 99% or more.

The properties of this material are shown below.

Kinematic viscosity 138.8cSt (40℃) 7.380cSt (100℃) Specific gravity (15/4℃) 0.9638 Refractive index (n ²⁰ _D ) 1.5100 The traction coefficient of this material from 60℃ to 140℃
Figure 1 shows the results measured over a temperature range of .

Comparative Example 1 500 ml of methylcyclohexane as a solvent and 156.0 ml of isoborneol as a raw material were placed in a four-necked flask 2 equipped with the same equipment as in Example 1.
g and 184.01 g of triethylamine were charged.
While stirring at room temperature, 146.84 g of cyclohexane carbonyl chloride was added to 100 g of methylcyclohexane.
ml solution was added dropwise over 4 hours. Thereafter, the reaction was carried out at 60°C for 2 hours to complete the reaction.

Next, after cooling to room temperature and filtering off the precipitated triethylamine hydrochloride, the solvent and unreacted raw materials were recovered using a rotary evaporator to obtain 252.51 g of the remaining reaction liquid. This is distilled under reduced pressure to obtain a fraction with a boiling point range of 121-131℃/0.2mmHg.
196.48g was obtained. This fraction was analyzed using nuclear magnetic resonance spectroscopy (NMR), infrared absorption spectrum (IR), and GC.
-As analyzed by MS and GC (FID),
Isobornyl cyclohexane carboxylate
It turned out to be 99%.

The properties of this product were as follows.

Kinematic viscosity 24.04cSt (40℃) 3.966cSt (100℃) Viscosity index 16 Specific gravity (15/4℃) 1.0062 Refractive index (n ²⁰ _D ) 1.4860 Furthermore, the traction coefficient of this product is set to 60℃
Measurements were made in the temperature range from to 140℃. The results are shown in FIG.

Comparative Example 2 A stirrer, a thermometer, and a dropping funnel were attached to the four-necked flask from 3, and 736 g of toluene was added to it.
Then, 200 g of concentrated sulfuric acid was charged as a catalyst, and the mixture was kept at 2°C in an ice bath and stirred.

Next, a mixed solution of 201 g of dihydrodicyclopentadiene and 92 g of toluene was added dropwise over a period of 6 hours. At this time, the temperature of the reaction solution had reached 7°C. Furthermore,
After stirring for 1 hour, the reaction solution was transferred to a separating funnel, the sulfuric acid layer was removed, and the organic layer was washed twice with 200 ml of 1N aqueous sodium hydroxide solution and twice with saturated brine, and then washed with anhydrous calcium sulfate. Dry.

After standing overnight, the desiccant was filtered off, and the solvent and unreacted raw materials were recovered using a rotary evaporator to obtain 240 g of the remaining reaction liquid.

Next, this is distilled under reduced pressure, with a boiling point of 122-125℃/0.2
192 g of a fraction of mmHg was obtained.

GC-MS and GC (FID) revealed that this product contained 99% or more of a component with 17 carbon atoms, which is dihydrodicyclopentadiene added to toluene.

80g of this fraction and 5% by weight ruthenium for hydrogenation/
10 g of activated carbon catalyst (manufactured by Nippon Engelhard Co., Ltd.) was placed in one autoclave, 200 g of methylcyclohexane was added as a solvent, and the hydrogen pressure was 80 Kg/cm ² G.
Hydrogenation was carried out at a reaction temperature of 160°C for 5 hours. After cooling, the catalyst was filtered off, the solvent was removed, and analysis revealed that the hydrogenation rate was 99% or more.

The properties of this material are shown below.

Kinematic viscosity 22.67cSt (40℃) 3.789cSt (100℃) Specific gravity (15/4℃) 0.9722 Refractive index (n ²⁰ _D ) 1.5112 Calculate the traction coefficient of this material from 60℃ to 140℃
Figure 1 shows the results measured over a temperature range of .

The traction coefficients in Examples 1 to 3 and Comparative Examples 1 and 2 were measured using a two-cylinder friction tester. In other words, one of the adjacent cylinders of the same size (diameter 52 mm, thickness 6 mm, driven side is a tyco type with a radius of curvature of 10 mm, and the driving side is a flat type without crowning) is moved at a constant speed (1500 rpm).
Then, the other cylinder was rotated continuously from 1500 rpm to 1750 rpm, a load of 7 kg was applied by a spring to the contact portion of both cylinders, the tangential force generated between the two cylinders, that is, the traction force was measured, and the traction coefficient was determined. This cylinder was made of bearing steel SUJ-2 with a mirror finish, and the maximum Hertzian contact pressure was 1.12 Kgf/mm ² .

In addition, when measuring the relationship between traction coefficient and oil temperature, the oil temperature was varied from 60℃ to 140℃ by heating the oil tank with a heater.
This is a plot of the relationship between traction coefficient and oil temperature at a slip rate of 5%.

As is clear from FIG. 1, the traction drive fluid of the present invention can maintain a high traction coefficient, particularly in a high temperature range, and is suitable as a traction drive fluid.

〔Effect of the invention〕

The traction drive fluid of the present invention containing such a bicyclo[2.2.1]heptane derivative has a high traction coefficient over a wide temperature range from room temperature to high temperature, and has a low viscosity.
Stirring loss is reduced and transmission efficiency is improved. As a result, the traction drive device can be made smaller and lighter and have a longer service life, and can be widely used in various mechanical products such as continuously variable transmissions for automobiles or industrial use, and even hydraulic equipment.

[Brief explanation of drawings]

FIG. 1 is a graph showing temperature changes in the traction coefficients of the traction drive fluids obtained in Examples 1 to 3 and Comparative Examples 1 and 2.

Claims (1)

[Claims] 1. General formula [In the formula, R ¹ to ^{R 12} each represent a hydrogen atom, a methyl group, an ethyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a trimethylcyclohexyl group, a decalyl group, or a methyldecalyl group. However, at least one of R ¹ to ^{R 12} is a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a trimethylcyclohexyl group, a decalyl group, or a methyldecalyl group. ] Bicyclo having 16 to 22 carbon atoms [2.2.1]
A traction drive fluid characterized by containing a heptane derivative. 2. The traction drive fluid according to claim 1, which contains at least 5% by weight of a bicyclo[2.2.1]heptane derivative.