JPH05230486A - Silicone grease composition - Google Patents

Abstract

(57) [Summary] (Modified) [Constitution] A silicone grease composition containing the following components. (a) Organopolysiloxane of the general formula (I) as base oil
30 to 96.5 _{wt% (CH 3) 3 SiO -} [- Si (R 1) (R 2) -O-] n -Si (CH 3) 3 (I) (R 1, R 2 is a methyl group A phenyl group is shown, and the proportion of the phenyl group in all the organic groups is 1 to 50 mol%. (B) The diurea compound of the general formula (II) 2 to 35% by weight R ³ -NH-CO-NH-R ⁴ -NH-CO-NH-R ⁵ (II) (R ⁴ is an aromatic hydrocarbon group having 6 to 15 carbon atoms, R ³ and R
⁵ is an aromatic hydrocarbon group having 6 to 12 carbon atoms or 8 carbon atoms
To 20 straight-chain alkyl groups, and the proportion of aromatic hydrocarbon groups in R ³ and R ⁵ is 10 to 100 mol%. (C) Epoxidized carboxylic acid ester 0.5 to 10 wt% (d ) Zinc dialkyldithiophosphate 0.5 to 10% by weight [Effect] Lubrication part that can suppress wear under high speed and low surface pressure, has a high dropping point, and is required to have high friction, wear resistance, and heat resistance. Can handle.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a silicone grease composition having improved heat resistance and abrasion resistance.
INDUSTRIAL APPLICABILITY The silicone grease composition of the present invention is used for a lubrication part that is required to have high abrasion resistance as well as abrasion resistance, more specifically for an overrunning clutch of an automobile starter, a one-way clutch of office equipment and various traction drive mechanisms. ..

[0002]

2. Description of the Related Art Organopolysiloxanes, that is, silicone oils are excellent in heat resistance, oxidative stability and viscosity-temperature characteristics, and it has been well known that silicone greases using these as base oils exhibit similarly excellent physical properties. ing. However, since silicone oil is inferior in steel-to-steel boundary lubrication performance, practical use of silicone grease using this as a base oil has been limited. Therefore, conventionally, a modified silicone oil in which a part of the substituents of the silicone oil is replaced with a chlorophenyl group, a fluoroalkyl group, a long chain alkyl group, a higher fatty acid residue, or the like, or a load bearing additive is added to the silicone oil. The boundary lubricity is improved by adding it. On the other hand, the grease that has been put to practical use in overrunning clutches and one-way clutches is a silicone grease or a polyol ester base oil grease in which a load-bearing additive is added and a lithium soap thickener is used. In addition, although the use example of grease in various traction drive mechanisms is not well known, synthetic naphthenic oil is used as lubricating oil.

However, the grease of polyol ester base oil does not have high frictional properties, and the synthetic naphthenic oil has disadvantages such as poor heat resistance. In addition, a modified silicone oil in which some of the substituents of the silicone oil are replaced with chlorophenyl groups, fluoroalkyl groups, long-chain alkyl groups, higher fatty acid residues, etc. to improve wear properties and seizure resistance The characteristic of high friction is lost. On the other hand, Japanese Patent Publication No. 2-21434 and Japanese Patent Laid-Open No. 62-
No. 283196 discloses the use of chlorine-based load-bearing additives. However, the point of improvement is wear under high surface pressure, that is, under extreme pressure lubrication conditions, which is different from wear under high speed and low surface pressure, which is a practical problem of overrunning clutches and the like. Further, for overrunning clutches and the like, there is a demand for grease that generates a large amount of heat and has excellent heat resistance due to the increase in speed that accompanies higher performance of the engine. However, the grease that is currently in practical use with lithium soap as a thickener has a dropping point of around 220 ° C even with grease using silicone oil as a base oil, and the grease can be used under conditions where the temperature due to the environment or heat generation exceeds 200 ° C. Is likely to soften or liquefy and leak.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to suppress the wear under high speed and low surface pressure without deteriorating the high friction property of silicone oil and to provide a silicone grease composition having a high dropping point. To provide things.

[0005]

The present invention has been achieved as a result of intensive research to solve the above problems, and the first embodiment is characterized by containing the following components (a) to (d). A silicone grease composition. (a) organopolysiloxane from 30 to 96.5 wt% of the following formula As the base oil _{(I) (CH 3) 3} SiO - [- Si (R 1) (R 2) -O-] n - Si (CH ₃ ) ₃ (I) (wherein R ¹ and R ² represent a methyl group or a phenyl group, and the proportion of the phenyl group in all the organic groups is 1 to 50 mol%) (b) Diurea compound represented by general formula (II) 2 to 35% by weight R ³ —NH—CO—NH—R ⁴ —NH—CO—NH—R ⁵ (II) (wherein R ⁴ has 6 to 6 carbon atoms). 15 aromatic hydrocarbon groups,
R ³ and R ⁵ represent an aromatic hydrocarbon group having 6 to 12 carbon atoms or a straight chain alkyl group having 8 to 20 carbon atoms, and R ³
And the ratio of the aromatic hydrocarbon group in R ⁵ is 10 to
(C) Epoxidized carboxylic acid ester 0.5 to 10% by weight (d) Zinc dialkyldithiophosphate 0.5 to 10% by weight Further, the second embodiment of the present invention is the following component (a). It is a silicone grease composition characterized by containing ~ (e). (a) Organopolysiloxane represented by the above general formula (I) as a base oil 30 to 96.5% by weight (b) Diurea compound represented by the above general formula (II) 2 to 35% by weight (c) Resistance Load additive 1.0 to 20% by weight (d) Graphite 0.5 to 15% by weight (e) Organic molybdenum 0.5 to 15% by weight

In the silicone grease composition of the present invention, the kinematic viscosity of the organopolysiloxane represented by the general formula (I) of the component (a) which is the base oil, that is, the silicone oil is not particularly limited, but is 20 to 10,000 cS at 25 ° C.
A value of t, preferably in the range of 50 to 2000 cSt, is suitable. This is because if it is less than 20 cSt, the base oil easily separates from the grease, and if it exceeds 10,000 cSt, the torque at a low temperature becomes large due to viscous resistance, which is not preferable in practice. Also, this silicone oil
Although it contains a phenyl group, if the content of this phenyl group is less than 1 mol% with respect to all the organic groups, the heat resistance is poor, and if it exceeds 50 mol%, the viscosity change due to temperature is large and the pour point is also high. Since it rises and the torque at low temperature increases, it is set to 1 to 50 mol%, but more preferably 3 to
It is preferable to set it in the range of 40 mol%.

Further, as a thickener, the general formula of the component (b)
The diurea compound represented by (II) is usually obtained by the reaction of diisocyanate and monoamine, and is one of the thickeners having a high dropping point. In the present invention, the proportion of aromatic hydrocarbon groups in the terminal groups of R ³ and R ^5, that is, diurea, is 10 to 100 mol%. 10 mol%
If it is less than the above, the dropping point of the obtained grease is about 220 ° C., and the high dropping point is not shown. The content of this thickener is 2
35% by weight, preferably 4 to 30% by weight.
If it is less than 2% by weight, it becomes liquid and cannot be used as grease. On the other hand, if it exceeds 35% by weight, the obtained grease is too hard and the low temperature torque becomes large, which is not preferable in practical use.
Examples of diisocyanates used in the present invention include:
Aromatic isocyanates such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, diphenylmethane 4,4'-diisocyanate and naphthylene-1,5-diisocyanate, and mixtures thereof can be mentioned. Examples of monoamines include aromatic amines such as aniline, benzylamine, toluidine, and chloroaniline, and octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, hexadecylamine. Mention may be made of linear aliphatic amines such as amines, heptadecylamine, octadecylamine, nonadecylamine, eicosylamine and mixtures thereof. In addition,
Greases containing components (a) and (b) of the present invention are described in U.S. Pat.
It is disclosed in No. 2,710,840.

In a first embodiment of the present invention, the epoxidized carboxylic acid ester of component (c) and the zinc dialkyldithiophosphate of component (d) prevent wear of the silicone grease on steel-to-steel at high speed and low surface pressure. Improve. Both the epoxidized carboxylic acid ester and the zinc dialkyldithiophosphate are known as load-bearing additives. Ingredient (c)
Examples of the epoxidized carboxylic acid ester include an ester of an epoxidized carboxylic acid and a monohydric alcohol. As the epoxidized carboxylic acid, any of aliphatic, alicyclic, aromatic monovalent and divalent or higher carboxylic acids can be used. The monohydric alcohol is an aliphatic, alicyclic, or aromatic alcohol, and is effective even if it has another substituent. Furthermore, epoxidized oils and fats, that is, glycerin esters of epoxidized fatty acids are also useful as the component (c) of the present invention, and examples thereof include epoxidized soybean oil and epoxidized linseed oil. The component (d), zinc dialkyldithiophosphate, is an organometallic compound having a structure represented by the following general formula (III), and R ⁶ and R ⁷ are roughly classified into alkyl groups and aryl groups. However, in the present invention, an alkyl group is more preferable. [(R ⁶ O-) (R ⁷ O-) PS (= S)-] ₂ Zn (III)

The second embodiment of the present invention contains graphite and organomolybdenum as essential components in addition to the base oil, the urea thickener and the load bearing additive. 0.5 to 15% by weight of graphite, based on the total weight of the composition, and 0.5 to 15% by weight of organomolybdenum, based on the total weight of the composition.
In the added silicone grease composition, the abrasion resistance is further improved. Here, graphite is a black powder known as a solid lubricant and is roughly classified into natural graphite produced naturally and purified artificial synthetic graphite. In the present invention, both of them can be used, but artificial graphite having less impurities such as silica content and high purity is more preferable. If the amount added is less than 0.5% by weight, there is no effect on wear resistance, and if it is more than 15% by weight, no further wear resistance effect is obtained. Organic molybdenum is a general term for organic metal salt-based load-bearing additives whose molybdenum group is molybdenum, and typical examples thereof include molybdenum dialkyldithiophosphate and molybdenum dialkyldithiocarbamate. Any of these organic molybdenums can be used in the present invention.

As the load-bearing additive of the component (c) in the second embodiment, in addition to the combination of the epoxidized carboxylic acid ester used in the first embodiment and zinc dialkyldithiophosphate, antimony dialkyldithiocarbamate and methyl ricinoleate are used. Known load-bearing additives can be used. When a combination of epoxidized carboxylic acid ester and zinc dialkyldithiophosphate is used, it is preferably added in an amount of 0.5 to 10% by weight based on the total weight of the composition. Further, in the grease composition of the present invention, if necessary, an amine-based or phenol-based antioxidant represented by phenyl α-naphthylamine, alkyldiphenylamine, di-tert-butylcresol, etc .; iron, cerium, nickel, titanium Heat-resistant additives typified by organic acid salts such as; rust inhibitors typified by alkenyl succinic acid derivatives and organic sulfonates; metal corrosion inhibitors typified by benzotriazole and its derivatives; epoxidized carboxylic acid esters, dialkyls Additives such as sulfurized olefins other than zinc dithiophosphate, load-bearing additives typified by organic molybdenum; and molybdenum disulfide other than graphite, solid lubricants typified by PTFE, and the like can be added.

The first silicone grease composition of the present invention comprises the use of a diurea compound as a thickener and a combination of an epoxidized carboxylic acid ester and zinc dialkyldithiophosphate as a load-bearing additive, which is an essential component.
Boundary lubrication performance, which is a drawback of conventional silicone grease,
Wear resistance is improved. Even if this particular combination of load-bearing additives is added to the grease using lithium soap as a thickener, the above effect is not observed. The detailed mechanism of this is unknown, but it is disclosed in JP-A-1-297.
JP 498 describes that zinc dialkyldithiophosphate prevented copper corrosion with a grease containing a urea thickener.
In this publication, it is presumed that due to the interaction between urea-based grease and zinc dialkyldithiophosphate, a zinc compound exists like a film on the copper plate surface and prevents the attack of other corrosive substances on the copper plate surface. That is, the anticorrosion property is caused only by the combination of zinc dialkyldithiophosphate and urea grease. In the present invention as well, a zinc compound film is similarly formed on the steel surface, which acts as a wear-resistant film, and it is speculated that the wear resistance is improved by the synergistic effect with the oily film of the epoxidized carboxylic acid ester.

The second grease composition of the present invention comprises
By adding graphite and organic molybdenum to the base oil, the urea thickener and the load bearing additive, the wear resistance is further improved. It is considered that this graphite prevents direct contact between the lubricated surfaces, contributes to smoothing of the lubricated surfaces, and further improves wear resistance. The proportion of the aromatic hydrocarbon group in the terminal group of the diurea compound of the component (b) used in the present invention is 10 to 10.
It is 0 mol%. The proportion of aromatic hydrocarbon groups is 10 mol%
If it is less than 100 ° C, the dropping point will be about 180 to 220 ° C.
When a urea compound having only an aromatic hydrocarbon group as the terminal group is used, a high dropping point grease of 260 ° C. or higher can be obtained.

[0013]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples. The greases of Examples and Comparative Examples were manufactured by the following method based on the blending components shown in Table 1. The grease performance evaluation test was carried out by the following method. (A) Mixing consistency ... According to JIS K2220 (b) Dropping point ... According to JIS K2220 (c) High-speed, low-load wear Wearing a roller by applying a load to the ring below and rotating the ring by applying a load Was measured with a micrometer. The test pieces and test conditions are as follows. Ring: outer diameter φ35 mm x width 8.7 mm, SAE4620STEEL, Rc58
~ 63, RMS6 ~ 12 Roller: Cylindrical roller for roller bearing, φ6mm x 6mm, SUJ-2 Surface pressure: 10 kgf / mm ² Peripheral speed: 12.8 m / sec

Examples 1-8, Comparative Examples 1-5, 7-8 Half of the base oil and the total amount of monoamine shown in Table 1 were placed in a reaction vessel and heated to 70-80 ° C. Half the amount of base oil and the total amount of diisocyanate were placed in another container and heated to 70 to 80 ° C., which was added to the reaction container and stirred. Although the temperature of the reaction product rises due to the exothermic reaction, stirring was continued in this state for about 30 minutes to carry out the reaction sufficiently, then the temperature was raised and the temperature was maintained at 170 to 180 ° C. for 30 minutes and cooled. Then, the total amount of the additives shown in Table 1, 10.0 g of alkenyl succinic anhydride as a rust inhibitor and 2.0 g of benzotriazole as a metal corrosion inhibitor were added and kneaded with a three-stage roll mill to obtain a target grease. Comparative Example 6 The total amount of base oil and the total amount of lithium (12-hydroxy) stearate shown in Table 1 were placed in a reaction vessel and heated to 220 ° C. This was cooled, and the total amount of the additives shown in Table 1, alkenyl succinic anhydride 10.0 g as a rust inhibitor and benzotriazole 2.0 g as a metal corrosion inhibitor were added and kneaded with a three-stage roll mill to obtain the desired grease. did.

In Table 1, phenyl 5 as a base oil is used.
%, 90 cSt means that the phenyl group content is 5 mol% and 2
This means an organopolysiloxane having a kinematic viscosity of 90 cSt at 5 ° C. Further, TDI is an abbreviation for a mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, and MDI is an abbreviation for diphenylmethane 4,4'-diisocyanate. In the epoxidized carboxylic acid ester, A is epoxidized stearyl octyl, B is epoxidized dioctyl hexahydrophthalate, and C is epoxidized soybean oil. Furthermore, zinc dialkyldithiophosphate, A is primary alkyl (Lubrizol 1360: made by Lubrizol), B is secondary alkyl (TLA-111: made by TEXACO).
Is. Graphite has 95% particle size of 15 μm
As the organic molybdenum, molybdenum dialkyldithiocarbamate (Sakura Robe 600: manufactured by Asahi Denka Co., Ltd.) was used. The raw materials used are all commercially available.

As shown in Examples 1 to 4, the grease of the present invention uses silicone oil as a base oil, but has little wear at high speed and low surface pressure and has a high dropping point. Further, as shown in Examples 5 to 8, the materials to which graphite and organic molybdenum are added have further improved abrasion resistance. On the other hand, as shown in Comparative Examples 1 to 3, when both the epoxidized carboxylic acid ester and the zinc dialkyldithiophosphate are not contained, and when only one is contained, the abrasion under high speed and low surface pressure is large, and the silicone grease The drawbacks have not been improved. Further, as shown in Comparative Example 4, the wear resistance is not improved even if only graphite and organic molybdenum are added. Further, in Comparative Example 5, the proportion of aromatic groups in the terminal groups of the thickener diurea compound is small, and a high dropping point grease cannot be obtained. Further, in Comparative Example 6, the thickening agent was lithium soap, but not only a high dropping point could not be obtained, but also abrasion resistance was low. In Comparative Examples 7-8,
Only load-bearing additives other than epoxidized carboxylic acid ester and zinc dialkyldithiophosphate were added, but the wear at high speed and low surface pressure was large.

[0017]

EFFECTS OF THE INVENTION The grease composition of the present invention is capable of suppressing wear at high speed under low surface pressure and having a high dropping point while using a silicone oil having a high friction property as a base oil. It can be applied to lubricated parts that require high friction, wear resistance and heat resistance.

[0018]

[Table 1] Examples and comparative examples Example 1 Example 2 Example 3 Example 4 Base oil Phenyl 5% Phenyl 10% Phenyl 35% Phenyl 5% 90cSt 1100cSt 450cSt 90cSt [g] 1528.0 1668.0 1708.0 1288.0 Thickener Diisocyanate TDI TDI MDI TDI [g] 161.4 124.2 40.6 224.0 Monoamine P-toluidine P-toluidine Aniline Aniline [g] 198.6 137.4 6.0 167.8 ─────────────────────── Octylamine Octylamine Stearylamine 18.4 33.4 208.2 Epoxy carbonic acid ester ABAC [g] 60.0 20.0 100.0 60.0 Dialkyl zinc thiophosphate AAAB [g] 40.0 20.0 100.0 40.0 Graphite [g] ── ── ── ── Organic molybdenum [g] ── ── ── ── Thickener amount [wt%] 18.0 14.0 4.0 30.0 Ratio of aromatic carbonized in R ³ and R ⁵ of formula (II) 100 90 20 70 Hydrogen [mol%] Mixing consistency 300 326 353 252 Drop point [℃] 260 <260 <258 260 < High speed / low load wear Wear [μm] 9 12 8 9

Table 1 (continued) Example 5 Example 6 Comparative Example 1 Comparative Example 2 Base oil Phenyl 5% Phenyl 10% Phenyl 5% Phenyl 5% 90cSt 1100cSt 90cSt 90cSt [g] 1508.0 1468.0 1628.0 1528.0 Thickener Diisocyanate TDI TDI TDI TDI [g] 152.4 124.2 161.4 161.4 Monoamine P-toluene P-toluene P-toluene P-toluene [g] 187.6 137.4 198.6 198.6 ──────────────────── Octylamine ─── 18.4 ─── ── Epoxylated carboxylic acid ester ABA [g] 60.0 20.0 ─── 100.0 Zinc dialkyldithiophosphate AA [g] 40.0 20.0 ─── ── Graphite [g] 40.0 100.0 Organic molybdenum [ g] 40.0 100.0 ── ── Amount of thickener [wt%] 17.0 14.0 18.0 18.0 Aromatic carbonization in R ³ and R ⁵ of formula (II) 100 90 100 100 Hydrogen ratio [mol%] Mixing consistency 298 303 298 303 Drop point [℃] 260 253 260 <260 < High speed / low load Wear [μm] 5 5 34 27

Table 1 (continued) Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Base oil Phenyl 5% Phenyl 5% Phenyl 5% Phenyl 5% 90cSt 90cSt 90cSt 90cSt [g] 1528.0 1508.0 1748.0 1688.0 Thickener Diisocyanate TDI TDI MDI [g] 161.4 152.4 69.4 Lithium (12 Monoamine P-Toluidine P-Toluidine Aniline Humanoxy) [g] 198.6 187.6 2.6 Stearate ────────────── 200.0 ─── ─── Octylamine 68.0 Epoxylated carboxylic acid ester AA [g] ─── ─── 60.0 60.0 Zinc dialkyldithiophosphate AAA [g] 100.0 ─── 40.0 40.0 Graphite [g] ── 70.0 ── ─ Organic molybdenum [g] ── 70.0 ── ── Thickener amount [wt%] 18.0 14.0 7.0 10.0 Aromatic carbonization in R ³ and R ⁵ of formula (II) 100 100 5 ── Hydrogen ratio [mol%] Admixture penetration 306 327 268 283 drops point [℃] 260 <257 219 212 speed and Load Wear [μm] 29 33 10 28

Table 1 (continued) Example 7 Example 8 Comparative Example 7 Comparative Example 8 Base oil Phenyl 5% Phenyl 35% Phenyl 5% Phenyl 35% 90cSt 450cSt 90cSt 450cSt [g] 1468.0 1608.0 1548.0 1808.0 Thickener Diisocyanate TDI MDI TDI MDI [g] 152.4 40.6 161.4 40.6 Monoamine P-toluidine aniline P-toluidine aniline [g] 187.6 6.0 198.6 6.0 ────────────────────octylamine octylamine ─── 33.4 ─── 33.4 Load-bearing additive [g] Dialkyldithioricinoleic acid Dialkyldithioricinoleic acid Carbamic acid Methyl carbamic acid Methyl antimony Antimony 80.0 100.0 80.0 100.0 Graphite [g] 100.0 100.0 ── ── Organic molybdenum [g] 100.0 100.0 ── ── Thickener amount [wt%] 17.0 4.0 18.0 4.0 Fragrance of R ³ and R ⁵ in formula (II) Group carbonization 100 20 100 20 Hydrogen ratio [mol%] Work penetration 295 342 295 355 Drop point [℃] 258 254 260 <259 High speed / low load wear [μm] 7 6 33 33

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C10M 137: 10 A 7419-4H 125: 02 139: 00) Z 7419-4H C10N 10:04 10: 12 30:06 30:08 40:04 50:10 (72) Inventor Masanori Toya 6-31, Roppongi, Minato-ku, Tokyo 6-31, Toshiba Silicon Corporation (72) Inventor Hideo Takahashi 6 Roppongi, Minato-ku, Tokyo 2nd to 31st Toshiba Toshiba Corp.

Claims (3)

[Claims] 1. A silicone grease composition comprising the following components. (a) organopolysiloxane from 30 to 96.5% by weight represented by the following general formula as a base oil _{(I) (CH 3) 3} SiO - [- Si (R 1) (R 2) -O-] n - Si (CH ₃ ) ₃ (I) (wherein R ¹ and R ² represent a methyl group or a phenyl group, and the proportion of the phenyl group in all the organic groups is 1 to 50 mol%) (b) Diurea compound represented by general formula (II) 2 to 35% by weight R ³ —NH—CO—NH—R ⁴ —NH—CO—NH—R ⁵ (II) (wherein R ⁴ has 6 to 6 carbon atoms) 15 aromatic hydrocarbon groups, R
³ and R ⁵ represent an aromatic hydrocarbon group having 6 to 12 carbon atoms or a linear alkyl group having 8 to 20 carbon atoms, and the ratio of the aromatic hydrocarbon group in R ³ and R ⁵ is 10 to 10
(C) Epoxidized carboxylic acid ester 0.5 to 10% by weight (d) Zinc dialkyldithiophosphate 0.5 to 10% by weight 2. A silicone grease composition comprising the following components. (a) organopolysiloxane from 30 to 96.5% by weight represented by the following general formula as a base oil _{(I) (CH 3) 3} SiO - [- Si (R 1) (R 2) -O-] n - Si (CH ₃ ) ₃ (I) (wherein R ¹ and R ² represent a methyl group or a phenyl group, and the proportion of the phenyl group in all the organic groups is 1 to 50 mol%) (b) Diurea compound represented by general formula (II) 2 to 35% by weight R ³ —NH—CO—NH—R ⁴ —NH—CO—NH—R ⁵ (II) (wherein R ⁴ has 6 to 6 carbon atoms) 15 aromatic hydrocarbon groups, R
³ and R ⁵ represent an aromatic hydrocarbon group having 6 to 12 carbon atoms or a linear alkyl group having 8 to 20 carbon atoms, and the ratio of the aromatic hydrocarbon group in R ³ and R ⁵ is 10 to 10
(C) 0 to 20% by weight (d) Graphite 0.5 to 15% by weight (e) Organic molybdenum 0.5 to 15% by weight 3. The load-bearing additive is 0.5 to 10% by weight, based on the total weight of the composition, of an epoxidized carboxylic acid ester,
And 0.5 to 10% by weight of the total weight of the composition of zinc dialkyldithiophosphate, the silicone grease composition of claim 2.