JPS61162595A - Grease composition - Google Patents

Abstract

PURPOSE:To obtain a grease composition suitable for use in the power transmission section of traction drive, by incorporating, as a consistency enhancer, specified amount of specific diurea compound in specific hydrocarbon compound as a base oil. CONSTITUTION:The objective composition can be obtained by incorporating (A) as a base oil, a hydrocarbon compound of formula I [R1-R3 are each 1-4C alkyl; R4 and R5 are each (1-4C alkyl-substituted) methylene, ethylene or trimethylene; a, b and c are each integer 0-2; x is 0 or 1] with (B) as a consistency enhancer, 3-25wt%, based on the whole amount of the final composition, of a diurea compound of formula II (R6 and R7 are each 1-4C alkyl; R8 is 6-18C-divalent hydrocarbon; d and e are each integer 0-2).

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a grease composition, and more particularly to a grease composition suitable for use in a power transmission part of a traction drive system. - (Prior art) In a power transmission unit of a traction drive device, for example, a planetary roller type traction drive device, power is transmitted using rolling friction generated by hardening of a lubricant oil film on a rolling contact surface. Therefore, the grease used therein is required to have excellent power transmission ability, that is, a high traction coefficient.

At the same time, the grease used in traction drive equipment is exposed to high temperatures and high loads, so even when used for long periods under such harsh conditions, there is little oil separation, and the grease has good dropping point, oxidation stability, and shear stability. It is necessary that the traction coefficient is excellent and that the traction coefficient does not decrease.

However, although various previously known greases satisfy some of the above-mentioned required properties, none satisfy all of them, and are not suitable for use in traction drive devices. Therefore, the inventors of the present invention conducted repeated research to develop a grease that satisfies the above required performance in all aspects. As a result, they used a hydrocarbon compound with a specific structure as a base oil, and added a diurea compound with a specific structure to this base oil. The present inventors have discovered that when used as a thickener, an excellent grease composition that satisfies all of the above-mentioned required performances can be obtained, leading to the completion of the present invention.

(Objective of the present invention) The inventor has a high traction coefficient and high temperature.

To provide a grease composition that exhibits little oil separation even when used under high loads for long periods of time, has perfect oxidation stability, excellent oxidation stability and shear stability, and does not reduce the traction coefficient, and is particularly suitable as a power transmission medium for traction drive devices. The purpose is to

(Contents of the present invention) The present invention includes two inventions, and the specific invention is based on (A) the general formula (wherein RL, R, and R3 represent an alkyl group having 1 to 4 carbon atoms, and R4 and R5 represent the hydrogen Atom has 1 carbon
methylene group, ethylene group or trimethylene group optionally substituted with ~4 alkyl groups, and atbtct
is an integer of 0 to 2, and X is an integer of 0 or 1, respectively) as a base oil,
(In the formula, R6 and R1 represent an alkyl group having 1 to 4 carbon atoms, R represents a divalent carbon hydrogen group having 6 to 18 carbon atoms, and d and e each represent an integer of 0 to 2. , ) is used as a thickener in an amount of 3 to 25% by weight based on the total amount of the composition.

Moreover, the second invention of the present invention is the above specified invention (^), CB)
As a third component in addition to the circumferential component.

(C) 0.1 to 10% by weight of one or more compounds selected from phosphate, phosphite, phosphoramidate, amine phosphate, molybdenum dithiophosphate, and molybdenum dithiocarbamate, based on the total amount of the composition. The present invention provides a grease composition comprising:

Hereinafter, the content of the present invention will be explained in more detail.

The base oil (A) component of the grease composition of the present invention has a primary (f
It is a hydrocarbon compound represented by formula 1.

[In formula 13, R, , R, and R1 have 1 carbon number
-4 alkyl group, R4 and R9 represent a methylene group, ethylene group or trimethylene group whose hydrogen atoms may be substituted with an alkyl group having 1 to 4 carbon atoms, preferably a methyl group, and a, b and C is an integer from 0 to 2, and
is O or 1 fl! It shows the number.

[R1, R, and R1 in formula 13 are specifically, for example, a methyl group, an ethyl group, or a propyl group.

A butyl group may be mentioned, and among them, a methyl group and an ethyl group are preferable. Also, as R1 and R.

Specifically, for example, methylene group, methylmethylene group (ethylidene group), dimethylmethylene group, ethylene group, methylethylene group, 1,1-dimethylethylene group, 1,2-
Dimethylethylene group, 1,1゜2-trimethylethylene group, tetramethylethylene group, trimethylene group, 1-methyltrimethylene group, 2-methyltrimethylene group, 1,
1-dimethyltrimethylene group, 1.2-dimethyltrimethylene group, 1.3-dimethyltrimethylene group, 2.2-
dimethyltrimethylene group, 1,1.2-trimethyltrimethylene group, l,1,3-trimethyltrimethylene group,
1,2.2-trimethyltrimethylene group, 1,2.3-
Trimethyltrimethylene group, 1.1,2.2-tetramethyltrimethylene group,! , l, 2.3-tetramethyltrimethylene group.

1.1,3,3-tetramethyltrimethylene group, 1.2
, 2,3-tetramethyltrimethylene group, etc. are mentioned as preferable groups.

In the present invention, it is used as a base oil for grease compositions. Preferred compounds represented by general formula (1) include, for example, dicyclohexylmethane, 1,1
-dicyclohexylethane.

1,2-dicyclohexyl ethane, 1,2-dicyclohexylpropane, 1,3-dicyclohexylpropane,
2.2-Dicyclohexylpropane.

1.2-dicyclohexyl-2-methylpropane, 1.
3-dicyclohexylbutane, 1,3-dicyclohexyl-3-methylbutane, 1,3-dicyclohexyl-2
, 3-dimethylbutane, 2,3-dicyclohexyl-2
, 3-dimethylbutane, 2,4-dicyclohexylpentane, 2,4-dicyclohexyl-2-methylpentane, bis-(cyclohexylmethyl)cyclohexane, bis-(1-cyclohexylethyl)cyclohexane.

Examples include bis-(l-methyl-2-cyclohexylethyl)cyclohexane, compounds in which the hydrogen atoms of the cyclohexyl ring of these compounds are substituted with 1 to 2 methyl groups or ethyl groups, and mixtures thereof.

Particularly preferred compounds as component (A) in the present invention are 1-cyclohexyl-1-methylcyclohexylethane, 1-cyclohexyl-1-ethylcyclohexylethane, 1-cyclohexyl-1-dimethylcyclohexylethane, bis -(1-cyclohexylethyl)methylcyclohexane.

Bis-(1-cyclohexylethyl)ethylcyclohexane, bis-(1-cyclohexylethyl)dimethylcyclohexane, 2,4-dicyclohexyl-2-methylpentane, and mixtures thereof.

On the other hand, the thickener (component (B)) of the grease composition of the present invention
is a diurea compound represented by the first-order [Ir) formula.

○ O [In formula 13, R& and R7 are an alkyl group having 1 to 4 carbon atoms, R1 is a divalent hydrocarbon group having 6 to 18 carbon atoms, and d and e are 0 to 2, preferably 0 to Each represents an integer of 1.

[[1] Specific examples of R5 and R7 in the formula include a methyl group, an ethyl group, a propyl group, and a butyl group, and among them, a methyl group and an ethyl group are preferred.

Further, R6 is specifically a hexylene group, an octylene group, a decylene group, a dodecylene group, a tetradecylene group,
Among the fullylene groups such as hexadecyl group and octadecyl group, phenylene group, tolylene group, xylene group, biphenylylene group, etc., diphenylmethane group is most preferable for R1 from the viewpoint of stability of the grease composition at high temperature and high load.

The blending amount of component (B) is 3 to 25% by weight, preferably 8 to 20% by weight based on the total amount of the grease composition.
It is.

In the present invention, by using the above-mentioned hydrocarbon compound as the component (A) as the base oil and using the diurea compound as the component (B) as the thickening agent, various performances were achieved. A grease composition particularly suitable for use in traction drive devices can be obtained, and the above-mentioned component (c) can be blended as a third component in order to further improve the performance regarding the traction coefficient and friction coefficient.

Component (C) in the present invention is one or more compounds selected from phosphate, phosphite, phosphoramidate, amine phosphate, molybdenum dithiophosphate, and molybdenum dithiocarbamate. Phosphate and molybdenum dithiocarbamate of the general formula herein refer to compounds of the general formula, respectively.

In the above formula, R9 and R1 represent an alkyl group having 1 to 24 carbon atoms, a cycloalkyl group, an alkylcycloalkyl group, an aryl group, an alkylaryl group, an arylalkyl group, R, , R1,, R, and R1 is a hydrogen atom or an alkyl group having 1 to 24 carbon atoms, a cycloalkyl group, an alkylcycloalkyl group, an aryl group, an alkylaryl group, an arylalkyl group, and f is O; f≦4
+g indicates a number such that 05g<4 and f+g=4.

Specifically, for example, R1 and R8.

Methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group,
Decyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group, eicosyl group, tocosyl group, tetracosyl group, cyclopentyl group, cyclohexyl group, methylcyclohexyl group, ethylcyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, phenyl group, tolyl group group, xylyl group, ethylphenyl group, propylphenyl group, butylphenyl group, pentylphenyl group,
hexylphenyl group, heptylphenyl group, octylphenyl group, nonylphenyl group, decylphenyl group, dodecylphenyl group, tetradecylphenyl group, hexadecylphenyl group, octadecylphenyl group, hennolhana,
Examples include phenethyl group. Also, R,..., R,
, R, and RL4 specifically include, for example, a hydrogen atom or the alkyl group, cycloalkyl group, alkylcycloalkyl group, aryl group, alkylaryl group, or arylalkyl group listed above.

Component (c) of the present invention is specifically, for example, monopentyl phosphate, monododecyl phosphate, dibutyl phosphate, dioctyl phosphate, didodecyl phosphate, diphenyl phosphate, tributyl phosphate, dibutylhexyl phosphate, butyl dioctyl phosphate, tridodecyl phosphate. Phosphate, dibutylphenyl phosphate, ethyl diphenyl phosphate, octyldiphenyl phosphate, triphenyl phosphate, tricresyl phosphate, benzyl diphenyl phosphate, didodecyl phosphite, tridodecyl phosphite, dibutylphosphoromonobutylamidate, dibutylphosphorodibutylamide Date, monooctylamine dibutyl phosphate, dibutylamine dibutyl phosphate, dioctylamine dibutyl phosphate, monododecylamine dibutyl phosphate, cyclohexylamine dibutyl phosphate, cyclohexylamine dioctyl phosphate, molybdenum sulfide diethyl dithiophosphate.

Molybdenum dipropyl dithiophosphate sulfide, molybdenum dibutyl dithiophosphate sulfide, moly sulfide, butyl dipentyl dithiophosphate, molybdenum dihexyl dithiophosphate sulfide, molybdenum dioctyldithiophosphate sulfide, molybdenum didecyl dithiophosphate sulfide, molybdenum didecyl dithiophosphate sulfide, molybdenum di(butyl sulfide) phenyl) dithiophosphate, molybdenum (nonylphenyl) dithiophosphate sulfide, oxymolybdenum sulfide diethyl dithiophosphate, oxymolybdenum sulfide dipropyl dithiophosphate, oxymolybdenum sulfide dibutyl dithiophosphate, oxymolybdenum sulfide dipentyl dithiophosphate, oxymolybdenum sulfide dihexyl dithiophosphate , oxymolybdenum sulfide dioctyldithiophosphate.

Oxymolybdenum didecyl dithiophosphate sulfide, oxymolybdenum didecyl dithiophosphate sulfide, oxymolybdenum di(butylphenyl) sulfide dithiophosphate, oxymolybdenum di(nonylphenyl) dithiophosphate sulfide, molybdenum dinityl dithiocarbamate sulfide, molybdenum dipropyl dithiocarbamate sulfide, molybdenum dibutyl dithio sulfide Carbamate, molybdenum sulfide dihexyl dithiocarbamate, sulfide molybdenum dioctyl dithiocarbamate, sulfide molybdenum didecyl dithiocarbamate, sulfide molybdenum didodecyl dithiocarbamate, sulfide molybdenum di(butylphenyl) dithiocarbamate.

Molybdenum sulfide di(nonylphenyl) dithiocarbamate, oxymolybdenum sulfide diethyl dithiocarbamate, oxymolybdenum sulfide dipropyl dithiocarbamate, oxymolybdenum sulfide dibutyl dithiocarbamate,
Oxymolybdenum sulfide dibentyldithiocarbamate,
Oxymolybdenum sulfide dihexyl dithiocarbamate,
Oxymolybdenum sulfide dioctyl dithiocarbamate,
Preferred compounds include sulfurized oxymolybdenum didecyl dithiocarbamate, sulfurized oxymolybdenum didodecyl dithiocarbamate, sulfurized oxymolybdenum di(butylphenyl) dithiocarbamate, sulfurized oxymolybdenum di(nonylphenyl) dithiocarbamate, and mixtures thereof, among which phosphate, molybdenum More preferred are dithiophosphates, molybdenum dithiocarbamates and mixtures thereof.

The blending amount of component (C) is 0.1 to 10% by weight, preferably 0.5 to 5% by weight based on the total amount of the grease composition.
It is.

Furthermore, in the grease composition of the present invention, various additives 1 such as antioxidants, viscosity index improvers, corrosion inhibitors, rust inhibitors, extreme pressure agents, tackiness improvers, etc. may be added as necessary. is also possible.

(Examples of the present invention) Hereinafter, the contents of the present invention will be explained in more detail with reference to Examples and Comparative Examples.

1st issue 2.4-dicyclohexyl-2-methylpentane 420
g diphenylmethane-4,4'-diisocyanate 6
7 g was added and heated to dissolve while stirring. In this solution,
A solution of 53 g of cyclohexylamine dissolved in 120 g of 2,4-dicyclohexyl-2-methylpentane was added, and the mixture was stirred vigorously while the liquid temperature was raised to 160° C., and then allowed to cool. When the temperature of the liquid decreased to 100°C, amine antioxidant Log, 0.5 g of corrosion inhibitor, and 30 g of adhesion improver were added, and after thorough stirring, three-roll milling was carried out to form a grease composition according to the present invention. I got something. The composition of this grease composition is shown in Table 1.

Performance evaluation of this grease composition was performed by the method shown below, and the results are also shown in Table 1.

[Consistency]

It was measured according to JIS K 22205.3.5 working penetration measurement method.

[Dripping point]

It was measured according to JIS K 22205.4 dropping point test method.

[Oil separation degree]

It was measured according to JIS 22205.7 oil separation test method.

[Towing coefficient]

Using a concave cylindrical rolling friction tester, the rolling speed was 310.
Measurements were made under the conditions of al/sec, load of 90 kg/m rd, and slip rate of 2%.

〔Coefficient of friction〕

Using an LFW-5 type friction tester, the sliding speed was 12.5a.
Measurement was made under the conditions of m/sec and a load of 1 kg/-.

In Example 1, bis-(1-cyclohexylethyl)dimethylcyclohexane was used instead of 2,4-dicyclohexyl-2-methylpentane, and the present invention was carried out in the same manner as in Example 1, except that Such a grease composition was obtained.

Table 1 shows the composition of this grease composition and the results of a performance evaluation test conducted in the same manner as in Example 1.

In Examples 1 and 2, the present invention (
Grease compositions according to the present invention were obtained in the same manner as in Examples 1 and 2, except that various compounds shown in Table 1 were added as components c).

Table 1 shows the compositions of these grease compositions and the results of performance evaluation tests conducted in the same manner as in Example 1.

Comparative Example 1 60 g of lithium 12-hydroxystearate was added as a thickener to 900 g of refined mineral oil with a viscosity of 10.5 cst (6100° C.) and a viscosity index of 95, and without stirring, 21
After heating to 0'C, it was allowed to cool. In this way, when the liquid temperature decreased to 100°C, the same amine antioxidant L as in Example 1
og, 0.5 g of a corrosion inhibitor, and 30 g of a tackiness improver were added thereto, and after thorough stirring, three-roll milling was performed to obtain a grease composition.

Table 1 shows the composition of this grease composition and the results of a performance evaluation test conducted in the same manner as in Example 1.

Number of layers ■1 In Comparative Example 1, 2,4-dicyclohexyl-2-methylpentane was used instead of refined mineral oil.

A grease composition was otherwise obtained in the same manner as in Comparative Example 1.

Table 1 shows the composition of this grease composition and the results of a performance evaluation test conducted in the same manner as in Example 1.

In Example 1, the refined mineral oil used in Comparative Example 1 was used in place of 2,4-dicyclohexyl-2-methylpentane, and a grease composition was prepared in the same manner as in Example 1 except for the following. Obtained.

Table 1 shows the composition of this grease composition and the results of a performance evaluation test conducted in the same manner as in Example 1.

(Effects of the present invention) As is clear from the results of the performance evaluation test in Table 1.

The grease composition according to the present invention has excellent properties such as good dropping point and oil separation, as well as high traction coefficient.

On the other hand, a known grease composition comprising mineral oil and lithium 12-hydroxystearate (Comparative Example 1) was significantly inferior to the grease composition of the present invention in most of the performance evaluation tests.

Furthermore, in the present invention, when the thickener is not the diurea compound of the present invention (Comparative Example 2), the dropping point and oil separation are significantly inferior to those of the grease composition of the present invention, and the traction coefficient is also lower than that of the thickener. It is getting worse due to the influence. On the other hand, when the base oil is not the hydrocarbon compound of the present invention, the traction coefficient is significantly inferior to that of the grease composition of the present invention.
The superiority of the grease composition of the present invention is clearly demonstrated.

Furthermore, when the component (c) of the present invention was further added to the grease compositions of Examples 1 and 2 (Examples 3 to 6), the traction coefficient was higher than that of the grease compositions of Examples 1 and 2. and the coefficient of friction are better, and the effect of adding component (C) is clearly visible.

Claims (1)

[Claims] 1) (A) General formula ▲ Numerical formula, chemical formula, table, etc. ▼ [I] (In the formula, R_1, R_2 and R_3 are an alkyl group having 1 to 4 carbon atoms, and R_4 and R_5 are methylene group, ethylene group or trimethylene group whose hydrogen atom may be substituted with an alkyl group having 1 to 4 carbon atoms, and a, b
, c, represent an integer of 0 to 2, and x represents an integer of 0 or 1, respectively. ) is used as a base oil, and (B) general formula ▲ has mathematical formulas, chemical formulas, tables, etc. ▼ [II] (In the formula, R_6 and R_7 are alkyl groups having 1 to 4 carbon atoms, R_9 represents a divalent carbon hydrogen group having 6 to 18 carbon atoms, and d and e each represent an integer of 0 to 2. A grease composition characterized by containing % by weight. 2) (A) General formula ▲ Numerical formula, chemical formula, table, etc. ▼ [ I ] (In the formula, R_1, R_2 and R_3 are alkyl groups with 1 to 4 carbon atoms, and R_4 and R_5 are hydrogen atoms whose hydrogen atoms have carbon atoms. methylene group, ethylene group or trimethylene group which may be substituted with 1 to 4 alkyl groups, and a, b
, c, represent an integer of 0 to 2, and x represents an integer of 0 or 1, respectively. ) is used as a base oil, and (B) general formula ▲ has mathematical formulas, chemical formulas, tables, etc. ▼ [II] (In the formula, R_6 and R_7 are alkyl groups having 1 to 4 carbon atoms, R_8 is a divalent carbon hydrogen group having 6 to 18 carbon atoms,
and d and e each represent an integer of 0 to 2. ) 3 to 25% by weight based on the total amount of the composition as a thickener, and (c) phosphate, phosphite, phosphoramidate, amine phosphate, molybdenum dithiophosphate and molybdenum dithiocarbamate. A grease composition comprising 0.1 to 10% by weight of one or more selected compounds based on the total amount of the composition.