JP6838924B2 - Grease composition and its manufacturing method - Google Patents

Description

The present invention relates to a low oil release grease and a method for producing the same.

In general, it is necessary to apply a lubricant to sliding parts in moving parts of various industrial machines and other devices, and grease is generally used as a lubricant especially in places where lubrication is difficult. There is. Such grease basically consists of a base oil and a thickener.

Further, in recent years, in order to improve the reliability and extend the life of the sliding member, a grease composition having excellent durability and lubrication performance is strongly demanded by the market, and the miniaturization of parts and the like is progressing. In order to meet these demands, solid lubricants and various additives have been used.

However, even in such a grease, the base oil is only retained in the network structure of the thickener, and there is a problem that the oil content is easily separated from the grease by long-term use and storage.

In order to solve such a problem, Patent Document 1 discloses a grease composition in which a styrene-based block copolymer is added to reduce the degree of oil release, but a grease composition containing a styrene-based block copolymer is disclosed. In some cases, it may be difficult to obtain the effect of the added solid lubricant due to the characteristics of the styrene-based block copolymer. In order to solve this problem, Patent Document 2 discloses a grease composition in which a liquid abrasion resistant agent is added at room temperature in addition to a solid lubricant, but the grease composition is free to design a formulation. The problem remains that it cannot be applied to applications where the degree of freedom is limited and the use of abrasion resistant agents is not preferred.

On the other hand, in Patent Document 3, the degree of oil release measured at a test temperature of 100 ° C. and a time of 24 hours using the method for measuring the degree of oil release specified in JIS K2220 is 0.1% by mass or more and 0.8% by mass. A grease composition characterized by the following is disclosed. However, as the consistency of the grease disclosed in the examples is 240 or less, there is a problem that the use of the grease composition is limited because it is hard. The document discloses a grease composition containing lithium hydroxystearate and a lithium fatty acid salt in a specific blending ratio and further containing an ethylene-propylene copolymer. Since the amount is large, the grease tends to be hard, and no solid lubricant is blended. As described above, the grease composition disclosed in Patent Document 3 may not be preferable as a general-purpose grease, leaving room for further improvement.

Similarly, in Patent Document 4, 100 ° C., 24 measured by JIS K2220, which comprises a specific base oil, a thickener selected from lithium soap, lithium composite soap, urea compound, and an additive of an amine compound or a phenol compound. Lubricating greases with a degree of oil release over time of 0 to 0.5 wt% are disclosed, but no solid lubricant is added to the grease, and as shown in the comparative example of the same document, as a base oil. There is a problem that a hydrocarbon-based synthetic oil or a silicone oil cannot be used. Furthermore, its use has been limited to the bearings of actuators and spindle motors in magnetic disc devices.

As described above, the known grease composition has an extremely low degree of oil release, is excellent in the softness defined by the consistency and the degree of freedom in formulation design, does not require a styrene block copolymer, and is a solid lubricant. A versatile grease composition capable of sufficiently exerting an effect has not been disclosed, and further improvement is required.

JP-A-2002-327188 Japanese Unexamined Patent Publication No. 2014-167075 Japanese Unexamined Patent Publication No. 2006-131763 JP-A-11-203777

An object of the present invention is to have a soft property with an immiscibility of more than 250 without using a styrene-based block copolymer, and to exhibit an extremely low level of oil release even after long-term use or storage. Moreover, it is an object of the present invention to provide a grease composition having a high degree of freedom in formulation design, a versatile and low oil release degree, in which the place of use is not limited, so that the effect of the solid lubricant can be fully exhibited. Furthermore, an object of the present invention is to provide a production method capable of easily producing the above-mentioned grease composition by a simple process.

As a result of diligent studies to solve the above problems, the present inventors have contained (A) a base oil, (B) a thickener other than a styrene block copolymer, and (C) a solid lubricant. According to the grease composition measured by the method specified in JIS K2220.11, the degree of oil release after 24 hours at 80 ° C. is 0.5% or less, and the immiscibility is in the range of 250 to 400. We have found that the problem can be solved and arrived at the present invention.

Similarly, the present inventors have found that the above-mentioned problems can be solved by a method for producing a grease composition having a step of adding an alcohol or an ester to the above-mentioned components (A) to (C) and mixing them. Reached.

According to the present invention, it has a soft property with an immiscibility of more than 250 without using a styrene-based block copolymer, and there is almost no problem of oil separation even after long-term use or storage. It is possible to provide a versatile grease composition having a high degree of freedom in formulation design, an unlimited use location, and a low oil release degree.

Furthermore, according to the present invention, it is possible to provide a production method capable of easily producing the above-mentioned grease composition by a simple process.

The first aspect of the present invention comprises (A) a base oil, (B) a thickener other than a styrene block copolymer, and (C) a solid lubricant, and is the method specified in JIS K2220.1. The grease composition is characterized in that the degree of oil release after 24 hours at 80 ° C. measured in 1 above is 0.5% or less, and the immiscibility consistency is in the range of 250 to 400. Hereinafter, the technical features will be described.

[(A) Base oil]
The base oil used in the present invention is not particularly limited, and examples thereof include mineral oils, synthetic oils, and silicone oils used in ordinary grease compositions. These can be used alone or as a mixture. As the mineral oil, those purified by appropriately combining vacuum distillation, oil removal, solvent extraction, hydrocracking, solvent desulfurization, sulfuric acid washing, white clay refining, hydrorefining and the like can be used.

Examples of synthetic oils include hydrocarbon-based synthetic oils, ester-based oils, ether-based oils, and the like. Examples of the hydrocarbon-based synthetic oil include alkylbenzenes such as monoalkylbenzenes and dialkylbenzenes, which are aromatic oils, and aliphatic oils such as monoalkylnaphthalene, dialkylnaphthalene, and polyalkylnaphthalene, normal paraffin, isoparaffin, and the like. Examples thereof include polybutene, polyisobutylene, polyalphaolefins (1-octene oligomers, 1-decene oligomers, ethylene-propylene oligomers, etc.) and hydrides thereof, and co-oligomers of alphaolefins and ethylenes. Examples of the ester-based oil include diester oils such as dibutyl sebacate, di-2-ethylhexyl sebacate, dioctyl adipate, diisodecyl adipate, ditridecyl adipate, ditridecylglutarate, and methyl acetylsinolate, or trioctyl remeritate. Aromatic ester oils such as tridecyl trimellitate and tetraoctylpyromellitate, as well as trimethylolpropane caprilate, trimethylolpropane verargonate, pentaerythritol-2-ethylhexanoate, pentaerythritol verargonate and the like. Examples thereof include polyol ester oils, and complex ester oils which are oligoesters of polyhydric alcohols and mixed fatty acids of dibasic acid and monobasic acid. Examples of the ether-based oil include phenyl ether oils such as monoalkyl triphenyl ether, alkyl diphenyl ether, dialkyl diphenyl ether, pentaphenyl ether, tetraphenyl ether, monoalkyl tetraphenyl ether, and dialkyl tetraphenyl ether.

Silicone oils include dimethyl silicone oil, methylphenyl silicone oil (phenyl-modified silicone oil), methylhydrogen silicone oil, polyether-modified silicone oil, aralkyl-modified silicone oil, fluoroalkyl-modified silicone oil, alkyl-modified silicone oil, and fatty acid ester. Examples include modified silicone oil.

From the viewpoint of versatility and technical effect as a base oil, the component (A) is preferably a hydrocarbon-based synthetic oil or a silicone oil, and an olefin-based hydrocarbon-based synthetic oil such as polyalphaolefin or dimethylsilicone. Oils or methylphenyl silicone oils are particularly preferred.

The range of the kinematic viscosity of the component (A) of the present invention is not particularly limited, but from the viewpoint of handling as a base oil and a grease composition, the kinematic viscosity of the mineral oil or synthetic oil at 40 ° C. is 10 to 10. The range of 600 mm2 / s is preferable, and the kinematic viscosity of the silicone oil at 25 ° C. is preferably in the range of 5 to 100,000 mm2 / s.

[(B) Thickeners other than styrene block copolymers]
The grease composition of the present invention is substantially free of styrene-based block copolymers, and is characterized in that a thickener other than styrene-based block copolymers is used. Here, the fact that the styrene-based block copolymer is substantially not contained means that the grease composition does not contain an amount of the styrene-based block copolymer that hinders the technical effect of the present invention, and is preferable. The content of the styrene-based block copolymer is 0.1 parts by mass or less, more preferably 0.01 parts by mass or less with respect to 100 parts by mass of the component (A), and the styrene-based block copolymer Is not intentionally added, that is, it is particularly preferable that the content of the styrene-based block copolymer is 0.00 parts by mass. When the grease composition of the present invention contains a styrene-based block copolymer, it is not preferable because it may hinder the lubricating effect and adversely affect the degree of freedom in formulation design, especially for solid lubricants.

The styrene-based block copolymer is disclosed in Patent Document 1 or Patent Document 2, and it is preferable not to add it to the grease composition of the present invention as a thickener, a thickener or any other additive. ..

The thickener other than the styrene-based block copolymer used in the present invention is not particularly limited, but a salt composed of a fatty acid and a metal is preferable. As the fatty acid, a fatty acid having 10 to 24 carbon atoms is preferably used, and usually castor oil fatty acid or hydrogenated castor oil fatty acid is used. Specific examples of other fatty acids include undecylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, 12-hydroxystearic acid, behenic acid and the like. These can be used alone or in combination of two or more. Specific examples of the metal include lithium, calcium, barium, potassium, strontium, sodium, aluminum and the like, and lithium salts of fatty acids are preferable. Such thickeners can be used alone or in combination of two or more. Particularly preferred is a thickener selected from the group consisting of lithium hydroxystearate and lithium stearate and lithium behenate.

The content of the component (B) of the present invention is not particularly limited, but the consistency of the obtained grease is preferably in the range of 250 to 400 in the immiscible consistency specified in JIS K2220. The immiscible consistency of the grease composition is preferably in the range of 270 to 350. The grease composition of the present invention can provide a grease having a consistency in the above range without using a styrene-based block copolymer, is soft, and has excellent versatility in a wide range of application. is there.

Specifically, the component (B) varies depending on the type or combination of the component (A) and the component (B) used, but is preferably 1 to 20% by mass based on the total amount of grease, and 100 parts by mass of the component (A). The component (B) is preferably in the range of 1 to 20 parts by mass, and more preferably in the range of 2 to 15 parts by mass.

[(C) Solid lubricant]
The solid lubricant used in the present invention is not particularly limited, and examples thereof include those used in ordinary grease compositions. Solid lubricants include molybdenum disulfide, tungsten disulfide, calcium stearate, mica, graphite, polytetrafluoroethylene (PTFE), melamine cyanurate, molybdenum dialkyldithiocarbamate and other lubricating resins and composites with an oxygen-deficient perovskite structure. such as oxides _{(Sr x Ca 1-x CuO} y , etc.). In addition, carbonates ( _{alkali metals such as Na 2} CO ₃ , CaCO ₃ , MgCO ₃ , carbonates of alkaline earth metals, etc.), silicates (M _{x Oy} SiO ₂ [M: alkali metals, alkaline earth metals, etc.) ] and the like), metal oxides (oxides of typical metal elements, oxides of transition metal elements, and composite oxides containing these metal elements [Al 2 _{O 3} / _MgO, etc.] and the like), a sulfide (PbS, etc.) , Fluoride (CaF ₂ , BaF _2, etc.), Carbide (SiC, TiC), Nitride (TiN, BN, AlN, Si ₃ N ₄ etc.), Cluster Diamond, and Fullerene C ₆₀ or C ₆₀ and C ₇₀ Examples thereof include fine particles such as a mixture, which can be expected to have an anti-seizure effect by suppressing direct contact between metals without extremely lowering the friction coefficient. Examples of the oxide of the typical metal element include Al ₂ O ₃ , CaO, ZnO, SnO, SnO ₂ , CdO, PbO, Bi ₂ O ₃ , Li ₂ O, K ₂ O, Na ₂ O, and B ₂ O. ₃ , SiO ₂ , MgO, In ₂ O _{3, and the} like can be mentioned. Among these, those in which the main group element is an alkaline earth metal, aluminum, or zinc are preferable. Examples of the oxide of the transition metal element include TiO ₂ , NiO, Cr ₂ O ₃ , MnO ₂ , Mn ₃ O ₄ , ZrO ₂ , Fe ₂ O ₃ , Fe ₃ O ₄ , Y ₂ O ₃ , and CeO _2. , CuO, MoO ₃ , Nd ₂ O _{3, and the} like.

Preferably, for example, fine particles of an organic compound composed of a fluororesin (particularly, polytetrafluoroethylene, tetrafluoroethylene hexafluoropropylene copolymer, etc.), polyethylene resin, polyamide resin, polypropylene resin, polyimide resin, silicone resin, etc., melaminesia. Examples thereof include fine particles of inorganic compounds such as nurate, molybdenum dialkyldithiocarbamate, molybdenum disulfide, graphite, silicon oxide, aluminum oxide and zinc oxide, fine particles of metals such as lead, and mixtures thereof. In particular, at least one solid lubricant selected from fluororesins, polyethylene resins, polyamide resins, molybdenum disulfide, molybdenum dialkyldithiocarbamate, graphite, aluminum oxide, zinc oxide, titanium oxide, zirconium oxide and mixtures thereof is used. Is preferable.

The grease composition of the present invention can contain the solid lubricant which is the above-mentioned component (C) in an amount of 1 to 50% by mass based on the total amount of grease, and the component (B) is based on 100 parts by mass of the component (A). Is preferably in the range of 1 to 50 parts by mass, and more preferably in the range of 2 to 20 parts by mass. If the component (C) is blended in excess of the above upper limit, the grease composition may exhibit hard properties, exceed the immiscibility range of the present invention, and impair its versatility and lubrication performance. is there.

[Degree of oil release]
The grease composition of the present invention has an oil release degree (according to JIS K2220 / 11) at 80 ° C. after 24 hours of 0.5% or less, and particularly preferably 0.4% or less. The degree of oil release can be substantially 0.0%, and a grease composition having a degree of oil release of 0.05 to 0.4% can be easily realized. That is, by using the production method described later, a grease composition containing a solid lubricant without using a styrene-based block copolymer and having a relatively soft property, but having an extremely low degree of oil release. Can be realized. Further, the grease composition of the present invention can realize a grease composition having an extremely low degree of oil release even when a hydrocarbon-based synthetic oil or a silicone oil is used as a base oil, and has versatility, lubrication performance, and so on. It is particularly excellent in durability and storage stability.

[Production method]
The grease composition of the present invention is not limited in the production method as long as it satisfies the above-mentioned composition and physical properties, but the addition is not limited to (A) base oil and (B) styrene-based block copolymer. It is convenient and preferable to obtain it by a production method having a step of adding and mixing the agent, (C) solid lubricant, and alcohol or ester. Here, the alcohol or ester mixed together with the other components (A) to (C) may remain in the grease composition, but lubrication based on the physical properties such as the consistency of the grease composition and the formulation design. From the standpoint of performance, it may be removed from the grease composition. That is, the final grease composition may or may not contain these alcohols or esters, preferably not.

The mixing ratio (mass ratio) of the above-mentioned component (A), component (B), and component (C) to alcohol or ester is not particularly limited, but the component (A), component (B), and component When the sum of the masses of (C) is 100 parts by mass, the alcohol or ester is preferably 3 parts by mass or more, and particularly preferably in the range of 4 to 20 parts by mass and 4 to 15 parts by mass. If the amount of alcohol or ester used is less than the above lower limit, the effect of suppressing oil separation becomes insufficient. On the other hand, when the proportion of alcohol or ester is excessive, it becomes difficult to finally remove it from the grease composition, and alcohol may remain in the grease. This may impair other properties of the grease composition as a lubricant and is uneconomical.

Specific examples of the alcohol used in the present invention include methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-nonanol, 1-decanol, 2-propanol, 2-butanol, 2 -Pentanol, 2-hexanol, 2-heptanol and the like can be mentioned. In particular, the alcohol is preferably a primary alcohol, ethanol, 2-propanol and the like are preferably used, and ethanol is particularly useful because it can be easily removed from grease by volatilization.

The ester used in the present invention may be a monoester or a diester, but a diester is preferable. The ester may be used in combination with the above alcohol or alone, but is particularly preferably used in combination with a primary alcohol.

Examples of the diester used in the present invention include diesters of dibasic acids such as glutaric acid, adipic acid, azelaic acid, sebacic acid and dodecanedioic acid, and alcohols such as 2-ethylhexanol, octanol, decanol, dodecanol and tridecanol. In particular, adipic acid ester is preferable, and dioctyl adipate is preferably used in combination with the above-mentioned primary alcohol.

When alcohol and ester are used in combination, the amount of alcohol used is preferably larger than the amount of ester used. Specifically, the mass ratio of alcohol to ester is 50:50 to 100: 0, preferably 60: It is in the range of 40 to 100: 0.

The method for mixing the components (A) to (C) with the alcohol or ester is not particularly limited, and a desired method such as stirring, rolling, or dispersing using mechanical force can be used. Preferably, the grease composition of the present invention can be easily produced by directly mixing the components (A) to (C) and an alcohol or ester and milling them through a roll mill.

In the above grease composition, when the component (B) is a metal salt of a fatty acid having 10 to 24 carbon atoms, the component (A) and the component (B1) consisting of a fatty acid for forming the component (B) are formed. ) And a component consisting of a compound containing a metal ion component for saponifying the component (B1) (for example, lithium hydroxide), and the component (C) is added after the component (B1) is saponified. It can also be manufactured by doing so.

Further, the method for producing a grease composition of the present invention further comprises heating or heating for removing the alcohol or ester after the step of mixing the component (A), (B), component (C) with the alcohol or ester. It may have a step of depressurizing. Preferably, after the above mixing step, it is convenient and preferable to heat and stir the composition containing the alcohol or ester, which is a preferable production method.

The grease composition of the present invention obtained by a production method using an alcohol or an ester is designed because, in addition to the above-mentioned usefulness, the alcohol or ester used in the production can be easily removed by using existing equipment or the like. There is a practical benefit of being able to obtain a grease composition having excellent oil release and consistency and excellent versatility and lubrication performance without changing or adversely affecting the formulation.

[Arbitrary component]
Further, in the grease composition of the present invention, solid particles, antioxidants, rust inhibitors, corrosion inhibitors, extreme pressure agents, oily agents, base oil diffusion inhibitors, corrosion inhibitors, metal deactivators, dyes , Color stabilizers, thickeners, structural stabilizers and other additives can be added as needed. In addition to these usual additives, various synthetic, recycled and natural fibers and adhesive substances such as rubber dust and cashew dust can be added.

The solid particles are components that impart a desired function to the grease composition according to the present invention. The type of solid particles is not particularly limited, but a reinforcing filler; a thickener; an abrasion resistant agent; a pigment; a coloring material; an ultraviolet absorber; a heat conductive filler; a conductive filler; an insulating material, etc. Functional particles of the above are exemplified. In addition, some particles can be blended as a plurality of functional particles.

Examples of the antioxidant include phenolic antioxidants such as 2,6-dith butyl-4-methylphenol and 4,4'-methylenebis (2,6-dith butylphenol), alkyldiphenylamines and triphenyls. Examples thereof include amine-based antioxidants such as amines, phenyl-α-naphthylamines, phenothiazines, alkylated-α-naphthylamines, and alkylated phenithiazines.
Examples of the rust preventive include fatty acids, fatty acid amines, alkyl sulfonic acid metal salts, alkyl sulfonic acid amine salts, paraffin oxide, polyoxyethylene alkyl ether and the like, and examples of corrosion inhibitors include benzotriazole and benzoimidazole. Examples include thiazizol and the like.

Examples of the extreme pressure agent include phosphorus compounds such as phosphoric acid ester, phosphite, and phosphoric acid ester amine salt, sulfur compounds such as sulfides and disulfides, dialkyl dithiophosphate metal salts, and dialkyl dithiocarbamic acid metal salts. Can be mentioned.

Examples of the oily agent include fatty acids or esters thereof, higher alcohols, polyhydric alcohols or esters thereof, aliphatic amines, fatty acid monoglycerides and the like.

Examples of the base oil diffusion inhibitor include a fluorine-based silane compound and an acrylic block copolymer.

The grease composition of the present invention can form a lubricating film by applying it to the surface of a sliding member made of a rubber member, a resin member, a metal member ceramic or the like.

In addition to the above-mentioned sliding members, the grease composition of the present invention can be used in all lubrication points to which grease can be applied, including lubrication points such as rolling bearings, sliding bearings, sliding surfaces, and gears. The method of applying and applying the grease composition of the present invention is not particularly limited.

The sliding member coated with the grease composition of the present invention can be effectively used as a driving component, a sliding component, or a transport component having the member. In particular, the grease composition of the present invention can be suitably used in a mechanical device such as an automobile, a copying machine or a printing machine having the sliding member.

The rubber members include timing belts, conveyor belts, sunroof body seals, glass runs, weather strips, oil seals, packings, wiper blades, doctor blades, charging rollers, developing rollers, toner supply rollers, transfer rollers, heat rollers, and addition. Pressure rollers, cleaning blades, paper feed rollers, conveyor rollers, doctor blades, intermediate transfer belts, intermediate transfer drums, heat belts, other drive members for automobiles, copiers, printers, etc., sliding members, conveyors, etc. Illustrated.

The resin members include door panels, instrument panels, door locks, bearings, gears, belt tensioners, fixing belts, pressure belts, other driving members for automobiles, copiers, printers, etc., sliding members, transport members, etc. Is exemplified.

The metal members include crankshafts, compressor shafts, slide bearings, gears, oil pump gears, pistons, piston rings, piston pins, gaskets, door locks, guide rails, seatbelt buckles, brake pads, brake pad clips, and brake shims. , Brake insulators, hinges, screws, pressure pads, other driving members for automobiles, copying machines, printers, etc., sliding members, transport members, etc. are exemplified.

There are no restrictions on the use of the members to which the grease composition of the present invention is applied, for example, home appliances, ships, railways, aircraft, machines, structures, automobile repairs, automobiles, construction, building materials, textiles, leather, stationery, etc. It can be used for woodworking, furniture, miscellaneous goods, steel plates, cans, electronic boards, electronic parts, printing, etc.

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited thereto.

[Examples 1 to 7 and Comparative Examples C1 to C5]
Each component was uniformly mixed with the components (A), (B), (C) and other components at the ratios shown in Tables 1 and 2, and treated with a three-roll mill. With respect to Examples 6 and Comparative Examples 2 and 3, a grease composition was obtained by further heating and stirring at 90 ° C. for about 1 hour to evaporate the component (C) and further defoaming. Grease compositions of Examples 1 to 7 and Comparative Examples C1 to C6 were obtained. The numerical values shown in Tables 1 and 2 represent parts by mass.

In Tables 1 and 2, each component is as follows.
<(A) Base oil>
(A1) Polyalphaolefin 1: 40 ° C. kinematic viscosity 17 mm ² / s
(A2) Polyalphaolefin 2: 40 ° C. kinematic viscosity 30 mm ² / s
(A3) Methylphenyl silicone oil: kinematic viscosity at 25 ° C. 125 mm ² / s (manufactured by Toray Dow Corning, SH550 fluid)
<(B) Thickeners other than styrene block copolymers>
(B1) Lithium 12-hydroxystearate (manufactured by Sakai Chemical Co., Ltd., S-7000H)
(B2) Lithium stearate (manufactured by Sakai Chemical Co., Ltd., S-7000)
(B3) Lithium behenate (manufactured by Nitto Kasei Kogyo, LS-7)
<(C) Solid lubricant>
(C1) Polytetrafluoroethylene (PTFE)
(C2) Melamine cyanurate (C3) Molybdenum dialkyldithiocarbamate (C4) Molybdenum disulfide <Other components>
(1) Ethanol (99.5): Kanto Chemical Co., Ltd., special grade reagent (2) Industrial ethanol: Japan Alcohol Trading Co., Ltd., Solmix AP-7 (ethanol 85.5 wt%, 1-propanol 9.6 wt%, 2-propanol 4.9 wt%)
(3) 2-propanol: Kanto Chemical Co., Ltd., reagent special grade (4) Dioctyl adipate (5) Glycerin: Kanto Chemical Co., Ltd., reagent special grade

For each Example and Comparative Example, the performance of the grease composition was evaluated by the following method, and the results are also shown in Tables 1 and 2. As shown in the examples, the above-mentioned production method contains a solid lubricant, does not use a styrene-based block copolymer, has an oil release degree of 0.5% or less, and has an immiscible consistency. A grease composition in a certain range could be obtained.

[Oil release degree test]
The degree of oil release after 24 hours at 80 ° C. was measured by JIS K222.11.

[Consistency]
The immiscibility was measured by JIS K2220.7.

Claims (8)

(A) a base oil, (B) styrenic block copolymer other than the thickener, a step of adding and mixing (C) a solid lubricant, and an alcohol,
Have a <br/> and removing by heating or reduced pressure the alcohol from the reaction system, the amount of the alcohol component (A), component (B), a total of 100 parts by weight, per third component (C) By mass or more, the alcohols are methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-nonanol, 1-decanol, 2-propanol, 2-butanol, 2-pen. A method for producing a grease composition selected from the group consisting of tanol, 2-hexanol, and 2-heptanol. The method for producing a grease composition according to claim 1, wherein the component (A) is a hydrocarbon-based synthetic oil or a silicone oil. The method for producing a grease composition according to claim 1 or 2, wherein the component (B) is composed of a metal salt of a fatty acid having 10 to 24 carbon atoms. The method for producing a grease composition according to any one of claims 1 to 3, wherein the component (B) is selected from the group consisting of lithium hydroxystearate, lithium stearate, and lithium behenate. A grease composition produced by the production method according to any one of claims 1 to 4, wherein the degree of oil release after 24 hours at 80 ° C. (according to JIS K2220 / 11) is 0.5% or less. and, the degree of non-worked penetration is Ri range near 250 to 400, substantially free of styrene block copolymer in the composition, the grease composition. (A) 100 parts by mass of base oil,
The grease composition according to claim 5 , wherein (B) contains 1 to 20 parts by mass of a thickener other than a styrene-based block copolymer, and (C) 1 to 50 parts by mass of a solid lubricant. .. The grease composition according to claim 5 or 6 , wherein the immiscibility is in the range of 270 to 350. The grease composition according to any one of claims 5 to 7 , which is a grease composition for a sliding member.