JP5643634B2 - Grease composition - Google Patents

Description

  The present invention relates to a grease composition having improved anti-fretting corrosion characteristics.

Fretting corrosion is also referred to as fretting corrosion, sliding corrosion, and fine movement wear, and is a wear phenomenon that occurs when two objects pressed at an arbitrary pressure repeatedly slide with a minute amplitude between contacts. When fine vibration and slight slip occur in two objects, the friction powder generated during the fine vibration of steel in the atmosphere becomes fine brown iron oxide (αFe ₂ O ₃ ), which is mixed with grease and turns brown. To do. The phenomenon that the grease turns brown occurs everywhere in the machine where the two contacting objects, such as the wheel bearings of the vehicle, the flanges to be bolted, and the leaf springs, are subject to relative slight vibration and slight slip. Fretting corrosion promotes wear of machine parts and bearings and also causes noise.

Many studies have been conducted on the characteristics and mechanism of this fretting corrosion, but it has not yet been clarified. Although it is not theoretically obtained from the fretting corrosion mechanism, a grease is used that has an effect that is phenomenologically recognized from the result of the test or practically.
That is, as a lubricating grease conventionally used for a lubrication location where fretting corrosion occurs, a high paraffinic low viscosity base oil and a high consistency (soft grease: a consistency of 320 or more is particularly effective. Non-patent Document 1) However, a sufficient effect is not always obtained.

  In addition, as an attempt to reduce this fretting corrosion, a grease composition for automobile wheel bearings in which an organic molybdenum compound is added to urea grease (Patent Document 1). A lithium soap grease composition to which one or more additives comprising an organic molybdenum compound, an organic fatty acid compound or an organic fatty acid derivative, and an organic phosphorus compound are added (Patent Document 2). A grease composition obtained by adding calcium sulfonate to a lithium soap grease using an ester oil as a base oil (Patent Document 3). Etc. are also known.

JP 2006-77056 A JP 2001-335792 A JP 2003-147378 A

NLGI Spokesman, Vol 45, 1 (1982)

  An object of this invention is to provide the lubricating grease composition which can improve a fretting corrosion-proof characteristic rather than the conventional lithium soap grease and urea grease.

The present invention includes (a) a base oil and (b) a thickening agent which is a lithium soap or urea compound , (c) a tricalcium phosphate, and (d1) an alkaline earth of oxidized wax , salicylate or phenate. Metal salt, (d2) Alkali metal salt of oxidized wax , salicylate or phenate, (d3) Oxidized wax, petroleum sulfonic acid, alkyl aromatic sulfonic acid, amine salt of salicylate or phenate, or (d4) Oxidized wax, petroleum sulfonic acid A grease composition comprising at least one selected from the group consisting of zinc salts of alkyl aromatic sulfonic acids, salicylates or phenates.

The alkaline earth metal salt of (d1) includes an alkaline earth metal salt of oxidized wax, an alkaline earth metal salt of salicylate, an alkaline earth metal salt of phenate, an overbased alkaline earth metal salt of oxidized wax, There is at least one selected from an overbased alkaline earth metal salt of salicylate and an overbased alkaline earth metal salt of phenate, and the alkaline earth metal is calcium or magnesium .

The alkali metal salt of (d2) includes an alkali metal salt of oxidized wax, an alkali metal salt of salicylate, an alkali metal salt of phenate, an overbased alkali metal salt of oxidized wax, an overbased alkali metal salt of salicylate, and There is at least one selected from overbased alkali metal salts of phenate, and the alkali metal is lithium or sodium.

Examples of the amine salt of (d3) include oxidized wax amine salts, petroleum sulfonic acid amine salts, alkyl aromatic sulfonic acid amine salts, salicylate amine salts, phenate amine salts, and oxidized wax overbased amine salts. And at least one selected from overbased amine salts of petroleum sulfonic acids, overbased amine salts of alkyl aromatic sulfonic acids, overbased amine salts of salicylates, and overbased amine salts of phenates.
The zinc salt (d4) includes at least one selected from a zinc salt of oxidized wax, a zinc salt of petroleum sulfonic acid, a zinc salt of alkyl aromatic sulfonic acid, a zinc salt of salicylate, and a zinc salt of phenate.
The alkaline earth metal salt (d1) , alkali metal salt (d2) , amine salt (d3) , and zinc salt (d4) are in a ratio of about 0.1 to 10% by mass with respect to the total composition of the grease composition. Used in.
Further, the tricalcium phosphate (c) is used in an amount of about 0.1 to 20% by mass relative to the total composition of the grease composition.

The grease composition of the present invention can improve fretting corrosion resistance. Further, as described above, the high-paraffinic low-viscosity base oil and the high consistency (soft grease: consistency of 320 or more) that are conventionally required may not be used. In the present invention, the No. 2 consistency [NLGI (French Consistency Number of the classification of (American Grease Association)) Even when a part of high viscosity oil or naphthenic base oil is used, excellent fretting corrosion resistance can be obtained.
Of course, this grease composition can be used for machines, bearings, gears, and the like that are generally used, and can exhibit excellent performance under severe conditions with finer vibrations. For example, it can be suitably used for parts such as needle bearings of automobile universal joints, constant velocity joints (CVJ), wheel bearings, ball screws, screws, flexible couplings, various gears, cams and chains.

As the base oil used in the grease composition of the present invention, mineral oils, synthetic oils, and mixed oils used in ordinary lubricating oils can be appropriately used, and the kinematic viscosity is about 20 to 400 mm at 40 ° C. Those of about ² / s are preferred.
In particular, base oils belonging to Group 1, Group 2, Group 3, Group 4, Group 5 in the API (American Petroleum Institute) base oil category can be used alone or as a mixture.

For Group 1 base oils, for example, paraffin obtained by applying a suitable combination of solvent refining, hydrotreating, dewaxing, etc., to a lubricating oil fraction obtained by atmospheric distillation of crude oil There are mineral oils.
For Group 2 base oils, for example, paraffinic mineral oil obtained by appropriately combining refining means such as hydrocracking and dewaxing for lubricating oil fractions obtained by atmospheric distillation of crude oil There is. Group 2 base oils refined by hydrorefining methods such as the Gulf Company method have a total sulfur content of less than 10 ppm and an aroma content of 5% or less, and can be suitably used in the present invention.

Group 3 base oil and Group 2 plus base oil include, for example, a paraffinic mineral oil produced by advanced hydrorefining and a dewaxing process for a lubricating oil fraction obtained by atmospheric distillation of crude oil. There are base oils refined by the ISODEWAX process for converting and dewaxing the produced wax to isoparaffins, and base oils refined by the mobile WAX isomerization process, and these can also be suitably used in the present invention.
GTL (Gas Liquid) synthesized by the Fischer-Tropsch method, which is a natural gas liquid fuel technology, has extremely low sulfur and aromatic content compared to mineral oil base oil refined from crude oil. Since the composition ratio is extremely high, the oxidation stability is excellent and the evaporation loss is very small. Therefore, it can be suitably used as the base oil of the present invention.

For Group 5 base oils, for example, naphthenes obtained by applying a suitable combination of solvent purification, hydrorefining, dewaxing, etc., to lubricating oil fractions obtained by atmospheric distillation of crude oil. There are system mineral oils, and these can also be suitably used in the present invention.
Moreover, the mixed oil of the above-mentioned paraffinic mineral oil and naphthenic mineral oil can also be used.

  Synthetic oils include, for example, polyolefins, dibasic acid diesters such as dioctyl sebacate, polyol esters, alkylbenzenes, alkylnaphthalenes, esters, polyoxyalkylene glycols, polyoxyalkylene glycol esters, polyoxyalkylene glycol ethers, polyphenyl ethers. , Dialkyl diphenyl ether, fluorine-containing compounds (perfluoropolyether, fluorinated polyolefin, etc.), silicone and the like.

  The polyolefin includes polymers of various olefins or hydrides thereof. Any olefin may be used, and examples thereof include ethylene, propylene, butene, and α-olefins having 5 or more carbon atoms. In the production of polyolefin, one of the above olefins may be used alone, or two or more may be used in combination. Particularly preferred are polyolefins called poly α-olefins (PAO), which are Group 4 base oils.

Urea compound Examples of the thickener are generally known, alkali metal soaps, Ken alkali metal composite stone, aluminum soaps, aluminum complex soaps, terephthalamate metal salt, clay, polytetrafluoroethylene, silica airgel (silicon oxide) The others can be used alone or in combination of two or more. In particular, lithium soaps and urea-based thickeners are often preferred in that they have few drawbacks and are excellent in practicality.

Tribasic calcium phosphate in the present invention is generally but those having a chemical structure of the hydroxyapatite composition represented by _[Ca 3 _{(PO 4) 2] 3 · Ca (OH) 2,} Ca 3 ( Those represented by PO ₄ ) ₂ can also be used.
In the examples and the like described below in the present invention, [Ca ₃ (PO ₄ ) ₂ ] ₃ · Ca (OH) ₂ is used, and the content is also expressed in mass based on this.
The tricalcium phosphate having an average particle size of 5 μm or less is preferable for increasing the consistency yield of the grease, but if it has an average particle size of 100 μm or less, it can be used without any problem.

The tricalcium phosphate is added to the grease composition, but is about 0.1 to 20% by weight, preferably about 1 to 15% by weight, more preferably about 2 to 2%, based on the total composition of the grease composition. It is good to mix | blend 10 mass%.
When the tribasic calcium phosphate is blended with the base oil, a thickening effect is also exhibited by the tribasic calcium phosphate, and even if the above-described lithium soap and urea and other thickeners are reduced, the composition is in a grease state. Furthermore, it can be in a state such as paste or compound.

  When the blending amount of this tricalcium phosphate is less than 0.1% by mass, excellent fretting corrosion resistance cannot be maintained. On the other hand, if the blending amount exceeds 20% by mass, the grease composition may solidify and not be in a smooth semi-solid state, which is often difficult to manufacture.

Examples of the alkaline earth metal salt (d1) include an alkaline earth metal salt of oxidized wax, an alkaline earth metal salt of salicylate, and an alkaline earth metal salt of phenate.
Furthermore, there are overbased alkaline earth metal salts of oxidized waxes, overbased alkaline earth metal salts of salicylates, and overbased alkaline earth metal salts of phenates which are these overbased products.
Examples of the alkaline earth metals, e.g., calcium, and the like magnesium.
As the alkaline earth metal salt, one or two of the above-mentioned ones can be used in combination.

Examples of the alkali metal salt (d2) include an alkali metal salt of oxidized wax, an alkali metal salt of salicylate, and an alkali metal salt of phenate, and further, an overbased alkali metal of oxidized wax which is an overbased product thereof. Salts, salicylate overbased alkali metal salts, and phenate overbased alkali metal salts.
Examples of the alkali metal include lithium, sodium, and potassium.
These alkali metal salts can be used alone or in combination of two or more.

Similarly, the amine salt of (d3) includes amine salt of oxidized wax, amine salt of petroleum sulfonic acid, amine salt of alkyl aromatic sulfonic acid, amine salt of salicylate, amine salt of phenate, and these overbases. Oxidized wax overbased amine salt, petroleum sulfonic acid overbased amine salt, alkyl aromatic sulfonic acid overbased amine salt, salicylate overbased amine salt, and phenate overbased amine There is salt.
As what produces said amine salt, ammonia, ethylenediamine, diethylenetriamine etc. are mentioned, for example.
These amine salts can be used in combination of one or more of those described above.

The zinc salt of (d4) includes zinc oxide oxide, zinc salt of petroleum sulfonic acid, zinc salt of alkyl aromatic sulfonic acid, zinc salt of salicylate, and zinc salt of phenate.
These zinc salts may be used alone or in combination of two or more.

Examples of the salt of the alkyl aromatic sulfonic acid include salts of an alkyl benzene sulfonic acid or an alkyl naphthalene sulfonic acid, and include those represented by the general formula (1) or the general formula (2).

In the above general formula (1) and general formula (2), M is the above amine or zinc, and R _n ¹ and R _n ² represent a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, preferably carbon. In the case where there are a plurality of these alkyl groups of formulas 6 to 18, they may be the same or different. n is an integer of 1 to 3, and h and k are integers of 1 to 2.

式（３）中、Ｍは上記アルカリ土類金属、アルカリ金属、アミン、亜鉛であり、好ましくはアルカリ土類金属であり、より好ましくはカルシウム又はマグネシウムである。Ｒ_ｎ ^３は、水素原子又は炭素数１〜４０の炭化水素基を示し、好ましくは炭素数６〜２２のアルキル基であり、それらが複数存在する場合は、それぞれ同一であっても異なってもよい。ｎは１〜４の整数、ｊは１〜２の整数である。 Examples of the salicylate salt include alkaline earth metal salts, alkali metal salts, amine salts, and zinc salts. Examples thereof include salicylates of the following general formula (3).

In formula (3), M is the above alkaline earth metal, alkali metal, amine, or zinc, preferably an alkaline earth metal, more preferably calcium or magnesium. R _n ³ represents a hydrogen atom or a hydrocarbon group having 1 to 40 carbon atoms, preferably an alkyl group having 6 to 22 carbon atoms, and when there are a plurality of them, they may be the same or different from each other. Good. n is an integer of 1 to 4, and j is an integer of 1 to 2.

  For example, the Ca-type salicylate can be used as it is, but the basic salt of Ca-type salicylate obtained by heating the normal salt of the Ca-type salicylate in the presence of excess Ca salt, Ca base and water, The overbased Ca salicylate obtained by reacting the salicylate normal salt with Ca carbonate or borate in the presence of carbon dioxide can also be used. Other overbased salts can be obtained according to the above.

  Examples of phenate salts include alkaline earth metal salts such as alkylphenols, alkylphenol sulfides, alkaline earth metal salts of Mannich reactants of alkylphenols, particularly magnesium salts or calcium salts and the like. Specifically, what is represented by the following general formula (4), (5), (6) can be mentioned, for example.

R ⁵ and R ⁶ in Formula 4, R ⁷ and R ⁸ in Formula 5, and R ⁹ and R ¹⁰ in Formula 6 may be the same or different and each independently represents a hydrocarbon group, preferably the number of carbon atoms A hydrocarbon group having 4 to 30 carbon atoms, more preferably an alkyl group having 9 to 22 carbon atoms, and in formulas 4, 5 and 6, M is an alkaline earth metal (preferably Ca, Ba, Mg). Yes, x is in the range of 1-3 depending on the specific metal involved.
Calcium and magnesium phenates are preferred for use in the present invention. Further, a multiphenate ring may be formed relative to the above-mentioned separated formula.

  The overbased alkaline earth metal phenate is an alkaline earth metal salt of alkylphenol or sulfurized alkylphenol, and is usually obtained by a method of carbonating an alkaline earth metal salt of alkylphenol or sulfurized alkylphenol.

One of these alkaline earth metal salts (d1) , alkali metal salts (d2) , amine salts (d3) , and zinc salts (d4) is selected from these, or can be used in combination as appropriate. The salt may be used in an amount of about 0.1 to 10% by weight, preferably about 1 to 8% by weight, more preferably about 2 to 7% by weight, based on the total composition of the grease composition.
When the addition amount is less than 0.1% by mass, excellent anti-fretting corrosion characteristics cannot be maintained, and when the addition amount exceeds 10% by mass, the improvement of the anti-fretting corrosion property is achieved. Often there is no increase in effectiveness.

  In addition to the above components, the grease composition of the present invention includes an antioxidant, an extreme pressure agent, a dispersant, a surfactant, an adhesion improver (such as a polymer), an oily agent, and a friction reducing agent, depending on the application. Antiwear agents, rust inhibitors, anticorrosive agents, solid lubricants, and other additives can be used in combination as appropriate.

  As the antioxidant, antioxidants such as amines, phenols, phosphites, sulfurs, dialkyldithiophosphates, etc. can be used. In particular, phenols and amines that are excellent in oxidation stability at high temperatures. A system is often preferred.

Examples of phenolic antioxidants include 2-t-butylphenol, 2-t-butyl-4-methylphenol, 2-t-butyl-5-methylphenol, 2,4-di-t-butylphenol, 2,4- Dimethyl-6-t-butylphenol, 2-t-butyl-4-methoxyphenol, 3-t-butyl-4-methoxyphenol, 2,5-di-t-butylhydroquinone (manufactured by Kawaguchi Chemical Co., Ltd .: Antage DBH), 2,6-di-t-butylphenol such as 2,6-di-t-butylphenol, 2,6-di-t-butyl-4-methylphenol, 2,6-di-t-butyl-4-ethylphenol 2,6-di-t-butyl- such as -4-alkylphenols, 2,6-di-t-butyl-4-methoxyphenol, 2,6-di-t-butyl-4-ethoxyphenol - there is a alkoxy phenols.
3,5-di-t-butyl-4-hydroxybenzyl mercapto-octyl acetate, n-octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate (manufactured by Yoshitomi Pharmaceutical Co., Ltd.) Tominox SS), n-dodecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2'-ethylhexyl-3- (3,5-di-t-butyl-4-hydroxy Phenyl-3-propionate, alkyl-3- such as benzenepropanoic acid 3,5-bis (1,1-dimethyl-ethyl) -4-hydroxy-C7-C9 side chain alkyl ester (Ciba Specialty Chemicals: Irganox L135) (3,5-di-t-butyl-4-hydroxyphenyl) propionates, 2,6-di-t-butyl-α- Methylamino-p-cresol, 2,2′-methylenebis (4-methyl-6-t-butylphenol) (manufactured by Kawaguchi Chemical Co .: Antage W-400), 2,2′-methylenebis (4-ethyl-6-t) There are 2,2′-methylenebis (4-alkyl-6-t-butylphenol) s such as (butylphenol) (manufactured by Kawaguchi Chemical Co., Ltd .: Antage W-500).

Further, 4,4′-butylidenebis (3-methyl-6-tert-butylphenol) (manufactured by Kawaguchi Chemical Co., Ltd .: Antage W-300), 4,4′-methylenebis (2,6-di-tert-butylphenol) (shell) -Japan company make: Ionox220AH), 4,4'-bis (2,6-di-t-butylphenol), 2, 2- (di-p-hydroxyphenyl) propane (shell Japan company make: bisphenol A), 2,2-bis (3,5-di-t-butyl-4-hydroxyphenyl) propane, 4,4′-cyclohexylidenebis (2,6-t-butylphenol), hexamethylene glycol bis [3- ( 3,5-di-t-butyl-4-hydroxyphenyl) propionate] (manufactured by Ciba Specialty Chemicals: Irganox L109), triethyl Renglycol bis [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate] (manufactured by Yoshitomi Pharmaceutical: Tominox 917), 2,2′-thio- [diethyl-3- (3 5-di-t-butyl-4-hydroxyphenyl) propionate] (manufactured by Ciba Specialty Chemicals: Irganox L115), 3,9-bis {1,1-dimethyl-2- [3- (3-t-butyl -4-hydroxy-5-methylphenyl) propionyloxy] ethyl} 2,4,8,10-tetraoxaspiro [5,5] undecane (Sumitomo Chemical: Sumilizer GA80), 4,4'-thiobis (3-methyl -6-t-butylphenol) (manufactured by Kawaguchi Chemical Co., Ltd .: Antage RC), bis such as 2,2′-thiobis (4,6-di-t-butyl-resorcin) There is a phenol compound.
Tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane (manufactured by Ciba Specialty Chemicals: Irganox L101), 1,1,3-tris (2-methyl) -4-hydroxy-5-t-butylphenyl) butane (Yoshitomi Pharmaceutical Co., Ltd .: Yoshinox 930), 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4 -Hydroxybenzyl) benzene (manufactured by Shell Japan: Ionox 330), bis- [3,3′-bis- (4′-hydroxy-3′-t-butylphenyl) butyric acid] glycol ester, 2- (3 ', 5'-di-tert-butyl-4-hydroxyphenyl) methyl-4- (2 ", 4" -di-tert-butyl-3 "-hydroxyphenyl) methyl Of polyphenols such as -6-tert-butylphenol, 2,6-bis (2'-hydroxy-3'-tert-butyl-5'-methyl-benzyl) -4-methylphenol, pt-butylphenol and formaldehyde Examples include condensates and phenol aldehyde condensates such as a condensate of pt-butylphenol and acetaldehyde.

  As amine-based antioxidants, p, p′-dioctyl-diphenylamine (manufactured by Seiko Chemical Co., Ltd .: non-flex OD-3), p, p′-di-α-methylbenzyl-diphenylamine, Np-butylphenyl- Dialkyl-diphenylamines such as Np'-octylphenylamine, monoalkyldiphenylamines such as mono-t-butyldiphenylamine and monooctyldiphenylamine, di (2,4-diethylphenyl) amine, di (2-ethyl-4 -Bis (dialkylphenyl) amines such as nonylphenyl) amine, alkylphenyl-1-naphthylamines such as octylphenyl-1-naphthylamine, Nt-dodecylphenyl-1-naphthylamine, 1-naphthylamine, phenyl-1- Naphthylamine, phenyl-2 Aryl-naphthylamines such as naphthylamine, N-hexylphenyl-2-naphthylamine, N-octylphenyl-2-naphthylamine, N, N′-diisopropyl-p-phenylenediamine, N, N′-diphenyl-p-phenylenediamine, etc. Phenylenediamines, phenothiazines (manufactured by Hodogaya Chemical Co., Ltd .: Phenothiazine), and phenothiazines such as 3,7-dioctylphenothiazine.

  The above extreme pressure agents and antiwear agents include sulfurized fats and oils, sulfurized olefins, sulfur compounds such as dithiocarbamates such as zinc dithiocarbamate and molybdenum dithiocarbamate, phosphates, acidic phosphates, phosphites, acidic Phosphorous compounds such as phosphorous acid esters, phosphoric acid ester amine salts, phosphorous acid ester amine salts, acidic phosphoric acid ester amine salts, acidic phosphorous acid ester amine salts, thiophosphoric acid esters, zinc dithiophosphate, It is possible to use sulfur phosphorus compounds such as dithiophosphates such as molybdenum dithiophosphate, molybdenum amine compounds, and other molybdenum compounds. In particular, an organomolybdenum compound having excellent friction and wear characteristics is preferable.

Examples of the rust preventive and anticorrosive include commonly used ones such as organic acid derivatives, particularly succinic acid ester derivatives, aspartic acid derivatives, sarcosine acid derivatives, 4-nonylphenoxyacetic acid, and the like. Preferably used.
Further, organic amine derivatives and organic amide derivatives, among them, diethanolamine, monoalkyl primary amine, diamine / difatty acid salt, diamine, amide of isostearic acid, amide of oleic acid and the like are preferable.
Other preferable examples include sulfurized fatty acids, surfactants (sorbitan trioleate, sorbitan tristearate, sorbitan monolaurate, mono-diglyceride of stearic acid / oleic acid, and the like).
In addition, a naphthenate, an alkali metal salt of a dibasic acid, an alkaline earth metal salt of a dibasic acid, or a benzotriazole derivative, a benzothiazole derivative, a benzimidazole derivative, or a thiocarbamate may be used. , Sodium sebacate and benzotriazole, or a combination thereof.

Examples of the solid lubricant include molybdenum disulfide, graphite, melanin cyanurate, boron nitride, mica, PTFE (polytetrafluoroethylene), and the like.
Of course, the above-mentioned other additives can be used in a state of being added in advance to a commercially available lubricating oil or semi-solid lubricating oil.

The present invention will be further described below with reference to examples and comparative examples, but the present invention is not limited thereby.
In preparing Examples and Comparative Examples, the following composition materials were prepared.
(1) Base oil A: a paraffinic mineral oil having a kinematic viscosity at 40 ° C. of 144.1 mm ² / s and a viscosity index of 96.
(2) Base oil B: a mixed oil of paraffinic mineral oil and naphthenic mineral oil, having a kinematic viscosity at 40 ° C. of 130.2 mm ² / s and a viscosity index of 79.
(3) Base oil C: A base oil belonging to API classification group 3 which is a paraffinic mineral oil produced by advanced hydrorefining with respect to a lubricating oil fraction obtained by atmospheric distillation of crude oil. A kinematic viscosity of 46.87 mm ² / s and a viscosity index of 127.
(4) Base oil D: Poly α-olefin (PAO) having a kinematic viscosity at 40 ° C. of 46.24 mm ² / s and a viscosity index of 137.

(5) Lithium soap: Lithium-12-hydroxystearate.
(6) Diurea compound: a reaction product of 2 moles of octylamine (C ₈ H ₁₇ NH ₂ ) and 1 mole of MDI (4,4′-diphenylmethane diisocyanate).
(7) Tricalcium phosphate: [Ca ₃ (PO ₄ ) ₂ ] ₃ · Ca (OH) ₂ , average particle diameter of about 5 μm.
(8) Calcium sulfonate (King Industries, Inc .; trade name Na-SUL 729).
(9) Calcium salicylate (Infineum Japan Ltd .; trade name Infineum M7121).
(10) Calcium phenate (Oronite Chemical Co .; trade name Oloa 229).
(11) Calcium salt of oxidized wax (Lublizol Corporation; trade name ALOX 165).
(12) Barium sulfonate (King Industries, Inc .; trade name Na-SUL BSN).
(13) Lithium sulfonate (King Industries, Inc .; trade name Na-SUL 707).
(14) Sodium sulfonate (King Industries, Inc .; trade name Na-SUL SS).
(15) Ammonium sulfonate (King Industries, Inc .; trade name Na-SUL AS).
(16) Diethylenetriamine sulfonate (King Industries, Inc .; trade name Na-SUL DTA).
(17) Ethylenediamine sulfonate (King Industries, Inc .; trade name Na-SUL EDS).
(18) Zinc sulfonate (King Industries, Inc .; trade name Na-SUL ZS-HT).

(Preparation of Examples and Comparative Examples)
Composition materials were mixed at the blending ratios shown in Tables 1 to 3, processed with a three-roll mill, and finished in a uniform state to obtain grease compositions of Examples 1 to 22.
Moreover, it was set as the mixture ratio shown to Table 4-Table 6, and it carried out similarly to the said Example, and obtained Comparative Examples 1-20.

(test)
In order to compare the characteristics of Examples 1 to 14, Reference Examples 1 to 8, and Comparative Examples 1 to 20, the following tests were performed.
(1) Consistency: Consistency (25 ° C., 60 W) was measured with respect to the consistency of the grease specified in JIS K2220 (ASTM D1403).
As for this consistency, the thing with a small numerical value has shown that the consistency is high.
(2) Fretting corrosion test: A test was conducted in accordance with ASTM D4170.
Test bearing: Thrust bearing 51203 (made by NSK Ltd.)
Grease amount: 1.0 ± 0.05g on the upper and lower test bearings
Thrust load: 2450N (550lb)
Amplitude: 0.21 radian (12 °)
Number of vibrations: 30 Hz <1800 cycles / min>
Test Temperature: Room temperature Test Time: 22hours
Anti-fretting corrosion characteristics
(Upper bearing race wear + Lower bearing race wear) / 2
The race mass loss (amount of wear) (mg) per set of bearings was calculated using the following formula.
Moreover, evaluation was displayed with the grades 1-4 according to the following reference | standard. Those with less wear are preferred.
Score 1: Anti-fretting wear amount 3.0 mg or less Score 2: Anti-fretting wear amount More than 3.0 mg to less than 4.5 mg Score 3: Anti-fretting wear amount 4.5 mg to less than 10.0 mg Score 4: Anti-fretting wear amount 10.0mg or more

(Test results)
The results of each test are shown in Tables 1-6.

(Discussion)
Examples 1 to 14 and Reference Examples 1 to 8 and Comparative Examples 1 to 20 have a consistency of 272 to 295, all having a consistency number of NLGI (American Grease Association) classification. The hardness of No. 2 (mixing consistency 265-295) is shown.
It can be seen that the anti-fretting corrosion characteristics of Examples 1 to 10 and Examples 12 to 14 all show “score 1” and are extremely excellent. Moreover, the thing of Example 11 has shown "score 2", and although it is not as high as "score 1", it is excellent and is practically inferior.
Furthermore, good results have been obtained when various base oils are used.
On the other hand, Comparative Example 2 to Comparative Example 7, Comparative Example 9, Comparative Example 11 to Comparative Example 15 and Comparative Example 17 to Comparative Example 20 are “rating 3”, and Comparative Example 1, Comparative Example 8, Comparative Example 10 and Comparative Example are compared. In Example 16, it was “score 4”, and it was found that the amount of wear was larger than that of the example and the characteristics were inferior.

Claims (7)

(A) a base oil, (b) a thickening agent which is a lithium soap or urea compound , (c) tricalcium phosphate, and (d1) an alkaline earth metal salt of an oxidized wax , salicylate or phenate, (d2) an oxidized wax , Alkali metal salt of salicylate or phenate, (d3) oxidized wax, petroleum sulfonic acid, alkyl aromatic sulfonic acid, amine salt of salicylate or phenate, or (d4) oxidized wax, petroleum sulfonic acid, alkyl aromatic sulfonic acid, salicylate or A grease composition containing at least one selected from the group consisting of zinc salts of phenates. The alkaline earth metal salt of (d1) is an alkaline earth metal salt of oxidized wax, an alkaline earth metal salt of salicylate, an alkaline earth metal salt of phenate, an overbased alkaline earth metal salt of oxidized wax , or salicylate. It contains at least one selected from the group consisting of an overbased alkaline earth metal salt and an overbased alkaline earth metal salt of phenate, and the alkaline earth metal is calcium or magnesium. The grease composition according to 1. The alkali metal salt of (d2) is an alkali metal salt of oxidized wax, an alkali metal salt of salicylate, an alkali metal salt of phenate, an overbased alkali metal salt of oxidized wax, an overbased alkali metal salt of salicylate, and phenate The grease composition according to claim 1, wherein the grease composition contains at least one selected from the group consisting of overbased alkali metal salts , and the alkali metal is lithium or sodium . The amine salt of (d3) is an amine salt of oxidized wax, an amine salt of petroleum sulfonic acid, an amine salt of alkyl aromatic sulfonic acid, an amine salt of salicylate, an amine salt of phenate, an overbased amine salt of oxidized wax, petroleum It contained at least one selected from the group consisting of overbased amine salts of sulfonic acids, overbased amine salts of alkyl aromatic sulfonic acids, overbased amine salts of salicylates, and overbased amine salts of phenates. The grease composition according to claim 1, wherein The zinc salt of (d4) is at least one selected from the group consisting of a zinc salt of oxidized wax, a zinc salt of petroleum sulfonic acid, a zinc salt of an alkyl aromatic sulfonic acid, a zinc salt of salicylate, and a zinc salt of phenate. The grease composition according to claim 1, wherein the grease composition is contained.   The grease composition according to any one of claims 1 to 5, wherein (c) tricalcium phosphate is contained in an amount of 0.1 to 20 mass% with respect to the grease composition. The grease composition comprises at least one content selected from the group consisting of the alkaline earth metal salt (d1), the alkali metal salt (d2), the amine salt (d3) and the zinc salt (d4) . The grease composition according to any one of claims 1 to 6, wherein the grease composition is 0.1 to 10% by mass relative to the mass.