WO2018020976A1

WO2018020976A1 - Solid lubricant, grease composition, lubricant composition for plastic working, method for producing solid lubricant and method for processing metal material

Info

Publication number: WO2018020976A1
Application number: PCT/JP2017/024803
Authority: WO
Inventors: 宏仁森; 俊樹後藤
Original assignee: 大塚化学株式会社
Priority date: 2016-07-28
Filing date: 2017-07-06
Publication date: 2018-02-01
Also published as: JPWO2018020976A1

Abstract

Provided are: a solid lubricant which is formed from a layered titanic acid compound and has a low friction coefficient; a grease composition and a lubricant composition for plastic working, each of which uses this solid lubricant; a method for producing a solid lubricant; and a method for processing a metal material. A solid lubricant formed from a layered titanic acid compound which has a layered structure formed of continuous chains of TiO₆ octahedrons, while having a cationic organic compound between layers, and which has an interlayer distance of 10 to 70 Å.

Description

Solid lubricant, grease composition, plastic processing lubricant composition, solid lubricant manufacturing method, and metal material processing method

The present invention relates to a solid lubricant, a grease composition and a plastic working lubricant composition using the same, a method for producing a solid lubricant, and a method for processing a metal material.

In the sliding part of the machine, a grease composition is used in order to improve the lubrication between the friction surfaces made of a metal material, a resin material, etc., and to make the operation smooth. However, under severe conditions such as a high load and a high speed region, there is a problem that the oil film is cut and the lubrication performance is deteriorated so that the friction surface is worn and finally seizure occurs. In order to solve such a problem, a grease composition containing a solid lubricant such as molybdenum disulfide, tungsten disulfide, and graphite has been conventionally used.

Also, when plastic working is performed on metal materials by forging, rolling, etc., the use of a lubricant is indispensable because the metal material, which is a workpiece, and a tool such as a die rub against each other at the friction interface. In recent plastic working, there is a demand for lubricants in order to reduce the machining with material loss as much as possible, and to economically manufacture workpieces with complex shapes and high dimensional accuracy, and with smoother surfaces. It is growing. For this reason, the surface pressure and surface area during processing increase, the processing difficulty increases, and processing that is difficult to cope with with the conventional plastic processing lubricant is increasing. As a lubricant for solving such problems, a lubricant composition containing a large amount of a solid lubricant such as molybdenum disulfide, tungsten disulfide, or graphite is used.

However, since solid lubricants such as molybdenum disulfide, tungsten disulfide, and graphite are black powders, contamination of the work environment becomes a problem, and non-black solid lubricants are required.

Boron nitride is known as a solid lubricant with white powder and high heat resistance. Moreover, as a solid lubricant of a white powder, Patent Document 1 discloses an organic modified clay mineral in which a cationic organic compound is supported between layers of a layered clay mineral.

On the other hand, titanate compounds are known as white powders, but Patent Documents 2 and 3 disclose a method of using them as friction modifiers for friction materials. In addition, the titanic acid compound can be used in Patent Document 4 as a layered titanic acid that has been delaminated and used for paints, resin fillers, cosmetics, pigments, etc., and performance such as heat resistance and slidability is required. It can be used in the following fields.

International Publication No. 2012/086564 Pamphlet International Publication No. 2002/010069 Pamphlet International Publication No. 2003/037797 Pamphlet International Publication No. 2003/016218 Pamphlet

However, the coefficient of friction of boron nitride and the compound of Patent Document 1 is high, and the solid lubricity is not sufficient. Since the titanate compounds disclosed in Patent Documents 2 and 3 are friction modifiers that are required to have a high friction coefficient and are stable, the friction coefficient is high. The delaminated layered titanic acid of Patent Document 4 has a problem that it aggregates when it is taken out as a powder, and a specific method of using it as a solid lubricant is not disclosed.

An object of the present invention is to provide a solid lubricant composed of a layered titanate compound having a low friction coefficient, a grease composition and a plastic working lubricant composition using the same, a method for producing the solid lubricant, and processing of a metal material It is to provide a method.

The present invention provides the following solid lubricant, grease composition, plastic working lubricant composition, solid lubricant manufacturing method and metal material processing method.

Item 1 A solid lubricant comprising a layered titanate compound having a layered structure formed by a chain of TiO ₆ octahedrons, a cationic organic compound between layers, and an interlayer distance of 10 to 70 mm.

Item 2 The precursor of the layered titanate compound is a lipid docrosite type lithium potassium titanate represented by the general formula K _{0.5 to 0.7} Li _0.27 Ti _1.73 O _{3.85 to 3.95} Alternatively, the solid lubricant according to Item 1, which is a lipidocrosite-type magnesium potassium titanate represented by the general formula K _{0.2 to 0.7} Mg _0.4 Ti _1.6 O _{3.7 to 3.95.} .

Item 3. The solid lubricant according to Item 1 or 2, wherein the content of the cationic organic compound is 10 to 99% by mass in 100% by mass of the whole layered titanate compound.

Item 4. The solid lubricant according to any one of Items 1 to 3, wherein the cationic organic compound is at least one selected from organic ammonium salts, organic phosphonium salts, and organic sulfonium salts.

Item 5. A grease composition containing the solid lubricant, base oil, and thickener according to any one of Items 1 to 4.

Item 6 The base oil is mineral oil, gas liquefied oil, diester synthetic oil, aromatic ester synthetic oil, polyol ester synthetic oil, ester synthetic oil, polyglycol synthetic oil, phenyl ether synthetic oil, synthetic Item 6. The grease composition according to Item 5, which is at least one selected from hydrocarbon oils, silicone-based synthetic oils, and fluorine-based synthetic oils.

Item 7: The thickener is an alkali metal soap, alkaline earth metal soap, alkali metal composite soap, alkaline earth composite metal soap, alkali metal sulfonate, alkaline earth metal sulfonate, aluminum soap, aluminum composite soap, terephthalate Item 7. The grease composition according to Item 5 or 6, which is at least one selected from metal salts, silica gel, clay, fluororesin, and urea compounds.

Item 8. A plastic working lubricant composition comprising the solid lubricant according to any one of Items 1 to 4.

Item 9. The plastic working lubricant composition according to Item 8, further comprising a binder component.

Item 10. The lubricant composition for plastic processing according to Item 9, wherein the binder component is at least one selected from a water-soluble inorganic salt, a water-soluble organic salt, and an organic polymer.

Item 11. The plastic working lubricant composition according to any one of Items 8 to 10, further comprising a lubricant component.

Item 12. The lubricant composition for plastic working according to Item 11, wherein the lubricant component is at least one selected from soaps, metal soaps, and waxes.

Item 13 is a method for producing the solid lubricant according to any one of Items 1 to 4, wherein the layered titanate is produced by subjecting the layered titanate to an acid treatment, A method for producing a solid lubricant, comprising a step of allowing basic compounds or salts thereof to act.

Item 14. A method for processing a metal material, wherein the solid lubricant according to any one of Items 1 to 4 is interposed at a friction interface between a workpiece and a processing tool.

Item 15. A method for processing a metal material, in which plastic working is performed by interposing the lubricant composition for plastic processing according to any one of Items 8 to 12 at a friction interface between a workpiece and a processing tool.

The solid lubricant of the present invention has a low coefficient of friction and can be suitably used as a grease composition, a plastic working lubricant composition, or the like.

FIG. 1 is a scanning electron micrograph showing the disk surface after a friction test in Example 1 of the present invention.

Hereinafter, an example of a preferable embodiment in which the present invention is implemented will be described. However, the following embodiments are merely examples. The present invention is not limited to the following embodiments.

<Solid lubricant>
The solid lubricant of the present invention comprises a layered titanate compound having a layered structure formed by a chain of TiO ₆ octahedrons, having a cationic organic compound between layers, and having an interlayer distance of 10 to 70 mm. .

The layer of the layered titanate compound is electrically neutral in nature, but is negatively charged by replacing part of the tetravalent Ti site with hydrogen ions or hydronium ions. This is compensated by a cationic organic compound, hydrogen ion, hydronium ion or metal ion between the layers. In addition, a part or layer of the Ti seat contains a monovalent to trivalent metal ion within the range where the layered titanate compound of the present invention has the excellent performance and is kept electrically neutral. It may be. However, it is preferable that the monovalent to trivalent metal ions are not substantially contained. Here, “substantially not contained” means that the content of monovalent to trivalent metal ions is 3% by mass or less in terms of oxide in 100% by mass of the whole layered titanate compound.

Examples of the cationic organic compound include at least one organic compound selected from organic ammonium salts, organic phosphonium salts, and organic sulfonium salts. Among these, organic ammonium salts are preferable. The organic compound has a hydrocarbon group and a cationic group.

In the present invention, the “cationic group” means a primary amine, a secondary amine, a tertiary amine, a quaternary ammonium salt, etc. described later, a hydrogen ion or a hydronium ion present in a layered titanate described later. Is a cationic group produced by the reaction.

In the present invention, the “hydrocarbon group” is a concept including an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group, and may be any of linear, branched, and cyclic forms. May be. Further, some carbon atoms constituting the hydrocarbon group may be substituted with other atoms (for example, O, S, etc.), and further, other bonds (for example, ester bonds, An ether bond).

The aliphatic hydrocarbon group is preferably an aliphatic hydrocarbon group having 1 to 40 (preferably 10 to 20) carbon atoms, and more specifically, an alkyl group having 1 to 40 (preferably 10 to 20) carbon atoms. Groups and the like. Examples of the alicyclic hydrocarbon group include cycloalkyl groups having 3 to 40 (preferably 6 to 20) carbon atoms. Further, the aromatic hydrocarbon group is preferably an aromatic hydrocarbon group having 6 to 40 (preferably 6 to 20) carbon atoms, more specifically an aryl having 6 to 40 (preferably 6 to 20) carbon atoms. And an aralkyl group having 7 to 40 (preferably 7 to 20) carbon atoms. Among these, linear alkyl groups having 1 to 40 (preferably 10 to 20) carbon atoms are preferable, and octadecyl, hexadecyl, dodecyl and the like are particularly preferable. When the long-chain alkyl group is not branched, the alkyl group is easily oriented in the vertical direction with respect to the titanate compound layer, and the titanate compound layer can be expanded to the desired interlayer distance and further maintained. Since it becomes easy, it is preferable.

The content of the cationic organic compound is preferably 10 to 99% by mass, more preferably 20 to 90% by mass, and more preferably 30 to 85% by mass in 100% by mass of the whole layered titanate compound. More preferred is 40 to 80% by mass.

The interlayer distance of the layered titanate compound of the present invention is 10 to 70 mm, preferably 20 to 60 mm, and more preferably 30 to 60 mm. The interlayer distance can be controlled by the kind and amount of the cationic organic compound. By setting the interlayer distance within this range, excellent solid lubricity (low friction coefficient) can be exhibited. If the interlayer distance is too large, delamination occurs, and when dried to a powder, it re-stacks and agglomerates. For this reason, it becomes difficult to maintain the interlayer distance. If the interlayer distance is narrow, excellent solid lubricity cannot be obtained.

The interlayer distance can be measured by, for example, X-ray diffraction. In the X-ray diffraction pattern, several peaks appearing at regular intervals in a low angle region (approximately 2θ = 20 ° or less) are derived from the titanic acid layer structure, and the diffraction angle of the primary peak appearing on the lowest angle side thereof. The interlayer distance can be calculated from (2θ). Specifically, Bragg's equation “d = nλ / 2sinθ” (d is the interlayer distance (Å), θ is the value obtained by dividing the diffraction angle (2θ) of the primary peak by 2, and λ is the wavelength of the CuKα ray. 1.5418Å, n can be calculated using a positive integer (n = 1 in the case of the primary peak).

The layered titanic acid compound of the present invention is powdery particles such as a spherical shape, a granular shape, a plate shape, a columnar shape, a block shape, an indefinite shape, and a shape having a plurality of convex portions (amoeba shape). The particle size is not particularly limited, but the average particle diameter is preferably 1 to 50 μm, more preferably 1 to 30 μm, and even more preferably 3 to 25 μm. In the present invention, the average particle diameter means a particle diameter at a cumulative reference cumulative 50% (volume reference cumulative 50% particle diameter) in a particle size distribution obtained by a laser diffraction / scattering method, that is, D ₅₀ (median diameter). The volume-based cumulative 50% particle diameter (D ₅₀ ) is obtained by calculating the particle size distribution on a volume basis, and counting the number of particles from the smallest particle size in the cumulative curve with the total volume being 100%. % Of the particle diameter. These various particle forms and particle sizes can be arbitrarily controlled by the shape of the layered titanate described later.

The layered titanate compound of the present invention can be produced using a layered titanate such as a lipidocrocite-type titanate. The layered titanate is a crystal having a layered structure formed by a chain of TiO ₆ octahedrons and having metal ions between the layers. This layer is inherently electrically neutral, but is negatively charged by substituting a part of the tetravalent Ti site with a 1 to 3 valent metal ion. The metal ions between the layers are compensated.

Examples of the lipidocrosite type titanate include a lipidocrosite type lithium potassium titanate represented by the general formula K _{0.5 to 0.7} Li _0.27 Ti _1.73 O _{3.85 to 3.95} , formula _{_{_{_{K 0.2 ~ 0.7 Mg 0.4 Ti 1.6}}}} O 3.7 ~ may be mentioned lepidocrocite type titanate magnesium potassium represented by _3.95, for example, Patent documents 2 and 3 can be produced by the method disclosed in 3.

The layered titanic acid compound of the present invention comprises a step (I) of producing a layered titanic acid by acid treatment of the layered titanate, and a basic compound or a salt thereof in the layered titanic acid obtained in the step (I). It can be produced by a method including the step (II) that acts.

In the step (I), the layer titanate is acid-treated to replace the metal ions substituting a part of the Ti site of the layer titanate and the metal ions between the layers with hydrogen ions or hydronium ions. Thus, layered titanic acid can be obtained. The layered titanic acid herein includes hydrated titanic acid in which water molecules exist between the layers.

The acid used for the acid treatment in the step (I) is not particularly limited, and may be a mineral acid such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, boric acid, or an organic acid. The acid treatment can be performed, for example, by adding an acid to an aqueous slurry of layered titanate and stirring. The exchange rate of metal ions can be controlled by appropriately adjusting the type and concentration of acid and the slurry concentration of layered titanate according to the type of layered titanate. From the viewpoint of the interlayer distance of the layered titanic acid compound to be obtained, it is preferably 70 to 100%.

In the step (II), a basic compound or a salt thereof is allowed to act on the layered titanic acid obtained in the step (I), and then dried, and a solvent such as water or an aqueous medium is removed. The layered titanic acid compound of the present invention can be produced.

The basic compounds or salts thereof used in the step (II) can be used without particular limitation as long as they have an interlayer swelling action of layered titanate and can be controlled to a target interlayer distance. At least one selected from primary to tertiary organic amines, organic ammonium salts, organic phosphonium salts, and organic sulfonium salts can be used. Among them, primary to tertiary organic amines and organic ammonium salts are preferable. Octadecylamine, hexadecylamine, hexadecylpyridinium chloride, benzalkonium chloride, and trimethylstearylammonium chloride are particularly preferred.

In the step (II), in order to act the basic compound or a salt thereof on the layered titanic acid, the basic compound or the salt thereof is directly added to a suspension obtained by dispersing the layered titanic acid in water or an aqueous medium, or A basic compound or a salt thereof diluted with water or an aqueous medium is added and stirred. The addition amount of basic compounds or salts thereof is preferably 0.05 to 2.0 equivalents of basic compounds or salts thereof, more preferably 0, relative to the exchangeable ion capacity of layered titanic acid. .2 to 1.3 equivalents. If it is 0.05 or less, it is impossible to increase the interlayer distance, and if it is 2.0 or more, it is not economically advantageous. Herein, the exchangeable ion capacity is a metal ion content replaceable, for example, when the layered titanate is represented by the general formula _{_{_{_{A x M y □ z Ti 2-}}}} (y + z) O 4, the valence of A A value represented by mx + ny when the number is m and the valence of M is n.

The basic compounds or salts thereof acted in step (II) react with hydrogen ions or hydronium ions between layers to form a cationic organic compound.

The solid lubricant of the present invention has a cationic organic compound between the layers of the layered titanate compound, so that the hydrocarbon group of the organic compound acts as a lubricating component and further appropriately controls the interlayer distance. It is considered that the coefficient of friction is reduced by cleavage.

Since the solid lubricant of the present invention has excellent solid lubricity, for example, a sliding portion between resin members, a sliding portion between metal members, or a sliding between a resin member and a metal member in a gear, a bearing, or the like. Grease composition used for parts, etc .; Lubricant for plastic working of metal materials; Lubricant composition for plastic working of metal materials; Cosmetics; Lubricant coating agent compositions;

<Grease composition>
The grease composition of the present invention contains the solid lubricant, the base oil and the thickener of the present invention. For example, in a gear, a bearing or the like, a sliding part between resin members, a sliding part between metal members, or a resin It can be used for the sliding part of a member and a metal member. Examples of the resin of the resin member lubricated using the grease composition of the present invention include polyethylene (PE) resin, polypropylene (PP) resin, ABS resin, polyacetal (POM), polyamide (PA) resin, and polycarbonate (PC). Resin, phenol resin, polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT) resin, polyphenylene sulfide (PPS) resin, polyether sulfone (PES) resin, polyimide (PI resin), polyether ether ketone (PEEK) resin, etc. Is mentioned.

The content of the solid lubricant of the present invention in the grease composition is preferably in the range of 0.1 to 50% by mass with respect to 100% by mass of the total amount of the grease composition, and preferably 1 to 20% by mass. A range is more preferable. If it is less than this range, lubricity may be insufficient. When it exceeds this range, there is a tendency that the grease composition is cured and the torque increases accordingly.

In the grease composition of the present invention, each component other than the solid lubricant of the present invention will be described below.

(Base oil)
The base oil is not particularly limited as long as it is a known base oil used in a grease composition, and includes, for example, vacuum distillation, solvent removal, solvent extraction, hydrocracking, solvent dewaxing, sulfuric acid washing, clay refining, Mineral oil refined from crude oil by appropriately combining treatments such as hydrorefining; gas liquefied oil (GTL oil) synthesized from natural gas by the Fischer-Tropsch method; dibutyl sebacate, di-2-ethylhexyl sebacate, Diester synthetic oils such as dioctyl adipate, diisodecyl adipate, ditridecyl adipate, ditridecyl glutarate, methyl acetyl cinnolate; Oil: Trimethylolpropane caprylate, trimethylolpropa Polyol ester synthetic oils such as pelargonate, pentaerythritol-2-ethylhexanoate, pentaerythritol belargonate; complex ester oils that are oligoesters of polyhydric alcohols and dibasic acids and mixed fatty acids of monobasic acids, etc. Ester synthetic oils: Polyglycol synthetic oils such as polyethylene glycol, polypropylene glycol, polyethylene glycol monoether, polypropylene glycol monoether, etc .; monoalkyl triphenyl ether, alkyl diphenyl ether, dialkyl diphenyl ether, pentaphenyl ether, tetraphenyl ether, mono Synthetic oils such as alkyl tetraphenyl ether and dialkyl tetraphenyl ether; normal paraffin, isopa Synthetic hydrocarbon oils such as fin, polybutene, polyisobutylene, 1-decene oligomer, 1-decene co-oligomer and other poly-α-olefins or their hydrides; dimethylpolysiloxane, diphenylpolysiloxane, alkyl-modified And silicone synthetic oils such as polysiloxane; fluorine synthetic oils such as perfluoropolyether; and the like. Among these, mineral oils and synthetic hydrocarbon oils are preferable from the viewpoint of consistency with lithium soap-containing grease compositions and compatibility with various additives.

The content of the base oil is preferably 50% by mass or more, and more preferably 70% by mass or more with respect to 100% by mass of the total amount of the grease composition. When the content of the base oil is less than 50% by mass, the fluidity of the grease composition is lowered and the torque tends to increase. Moreover, 99 mass% or less is preferable with respect to 100 mass% of total amounts of a grease composition, and, as for content of a base oil, 95 mass% or less is more preferable. When the content of the base oil exceeds 99% by mass, excessive oil separation is caused, and there is a tendency for leakage from the use location, scattering, and the like.

(Thickener)
The thickener is not particularly limited as long as it is a known thickener used in grease compositions. For example, alkali metal soap (lithium soap, sodium soap, etc.), alkaline earth metal soap (calcium soap, etc.) , Alkali metal composite soap, alkaline earth composite metal soap, alkali metal sulfonate, alkaline earth metal sulfonate, aluminum soap, aluminum composite soap, terephthalate metal salt, silica gel, clay, fluororesin, urea compound (aromatic diurea, Aliphatic diurea, alicyclic diurea, triurea, tetraurea, etc.). Among these, alkali metal soap is preferable from the viewpoint of heat resistance, and lithium soap is more preferable.

The type of lithium soap is not particularly limited, and lithium soap synthesized from a higher fatty acid having 10 to 28 carbon atoms and / or a higher hydroxy fatty acid having 10 or more hydroxyl groups and having 10 or more hydroxyl groups can be used. . Examples of the higher fatty acid include lauric acid, palmitic acid, stearic acid, linoleic acid, arachidic acid, myristic acid, pentadecanoic acid, heptadecanoic acid, oleic acid, arachidonic acid, and behenic acid. Examples of the higher hydroxy fatty acid include 12-hydroxystearic acid, 12-hydroxylauric acid, and 16-hydroxypalmitic acid. Specific examples of the lithium soap include lithium laurate, lithium stearate, and lithium 12-hydroxystearate.

The content of the thickener is preferably 2% by mass or more, and more preferably 5% by mass or more with respect to 100% by mass of the total amount of the grease composition. When the content of the thickener is less than 2% by mass, the grease composition is too soft and tends to scatter and leak and cause excessive oil separation. Further, the content of the thickener is preferably 60% by mass or less, and more preferably 30% by mass or less, with respect to 100% by mass of the total amount of the grease composition. When the content of the thickener exceeds 60% by mass, the grease composition becomes hard and tends to increase the torque at the point of use, and to cause seizure resistance and wear resistance to decrease due to a decrease in fluidity. There is.

(Other ingredients)
The grease composition of the present invention is a solid lubricant other than the solid lubricant of the present invention, an antioxidant, an extreme pressure agent, a rust inhibitor, a corrosion inhibitor, and other components as long as the effects of the present invention are not impaired. Viscosity index improvers, oily agents and the like may be contained.

Examples of the solid lubricant other than the solid lubricant of the present invention include organic modified clay minerals, molybdenum disulfide, tungsten disulfide, graphite, fluorinated graphite, hexagonal boron nitride (h-BN), mica described in Patent Document 1. , Talc, calcium carbonate, basic magnesium carbonate, basic zinc carbonate, calcium hydroxide, magnesium hydroxide, magnesium oxide, calcium phosphate, zinc phosphate, aluminum dihydrogen tripolyphosphate, polytetrafluoroethylene (PTFE), melamine cyanurate And amino acid compounds.

Antioxidants include phenols such as 2,6-di-t-butyl-4-methylphenol and 4,4′-methylenebis (2,6-di-t-butylphenol), alkyldiphenylamines (the alkyl group is Having 4 to 20 carbon atoms), amine-based antioxidants such as triphenylamine, phenyl-α-naphthylamine, phenothiazine, alkylated phenyl-α-naphthylamine, phenothiazine, alkylated phenothiazine, phenolic amine-based antioxidants, Examples thereof include phosphite amine antioxidants, sulfur amine antioxidants, and dialkyl dithiophosphates.

Extreme pressure agents include sulfurized olefin, sulfurized ester, sulfite, thiocarbonate, chlorinated fatty acid, phosphate ester, phosphite ester, molybdenum dithiocarbamate (MoDTC), molybdenum dithiophosphate (MoDTP), zinc dithiophosphate (ZnDTP) ), Etc., organic molybdenum extreme pressure agents, phosphorus extreme pressure agents, chlorine extreme pressure agents and the like.

Examples of rust preventives include alkyl sulfonates, fatty acid amines, oxidized paraffins, and polyoxyethylene alkyl ethers.

Corrosion inhibitors include benzotriazole, benzimidazole, thiadiazole and the like.

Examples of the viscosity index improver include polymethacrylate, ethylene-propylene copolymer, polyisobutylene, polyalkylstyrene, styrene-isoprene copolymer hydride, and the like.

Examples of the oil-based agent include fatty acids, higher alcohols, polyhydric alcohols, polyhydric alcohol esters, aliphatic esters, aliphatic amines, fatty acid monoglycerides and the like.

The content of other components is preferably 0.1 to 10% by mass and more preferably 0.25 to 5% by mass with respect to 100% by mass of the total amount of the grease composition.

<Lubricant composition for plastic working>
When the solid lubricant of the present invention is used as a plastic working lubricant for a metal material, for example, the solid lubricant of the present invention is also used as a plastic working lubricant composition in which a binder component, a lubricant component, etc. are blended. Can do. The content of the solid lubricant of the present invention in the plastic working lubricant composition is preferably in the range of 5 to 95% by mass with respect to 100% by mass of the total amount of the lubricant composition. More preferably, it is in the range of mass%. If it is less than this range, lubricity may be insufficient. If it exceeds this range, it may be difficult to keep the solid lubricant of the present invention in the film.

(Binder component)
The binder component is used as a coating component for introducing and holding the solid lubricant composition of the present invention at the friction interface between the workpiece and the processing tool. Binder components include water-soluble inorganic salts such as sulfate, silicate, borate, molybdate, vanadate, tungstate; malate, succinate, citrate, tartrate, etc. Water-soluble organic salts; organic polymers such as vinyl resins, acrylic resins, amide resins, epoxy resins, phenol resins, urethane resins and polymaleic acid resins are exemplified.

The binder component is preferably in the range of 5/95 to 95/5, more preferably in the range of 15/85 to 90/10 in terms of mass ratio (solid lubricant of the present invention) / (binder component). preferable.

(Lubricant component)
Lubricant components include soaps (sodium stearate, potassium stearate, sodium oleate, etc.), metal soaps (calcium stearate, magnesium stearate, aluminum stearate, barium stearate, lithium stearate, zinc stearate, palmitic acid) And at least one selected from waxes (polyethylene wax, polypropylene wax, carnauba wax, beeswax, paraffin wax, microcrystalline wax, etc.).

The lubricant component is preferably in the range of 25/75 to 100/0 in terms of mass ratio (solid lubricant of the present invention) / (lubricant component).

(Other ingredients)
The plastic working lubricant composition of the present invention includes, as other components, solid lubricants other than the solid lubricant of the present invention, extreme pressure agents, corrosion inhibitors, viscosity modifiers, oils, surfactants, A molecular dispersant may be contained.

Extreme pressure agents include sulfurized olefin, sulfurized ester, sulfite, thiocarbonate, chlorinated fatty acid, phosphate ester, phosphite ester, molybdenum dithiocarbamate (MoDTC), molybdenum dithiophosphate (MoDTP), zinc dithiophosphate (ZnDTP) ) And the like, organic molybdenum extreme pressure agents, phosphorus extreme pressure agents, and chlorine extreme pressure agents.

Examples of corrosion inhibitors include phosphites, zirconium compounds, tungstates, vanadates, tungstates, silicates, borates, carbonates, amines, benzotriazoles, chelate compounds, and the like. .

Examples of the viscosity modifier include hydroxyethyl cellulose, carboxymethyl cellulose, polyacrylic amide, sodium polyacrylate, polyvinyl pyrrolidone, polyvinyl alcohol, smectite clay mineral, finely divided silica, bentonite, kaolin and the like.

Examples of oils include vegetable oils, mineral oils, and synthetic oils.

Examples of surfactants and polymer dispersants include nonionic surfactants, anionic surfactants, amphoteric surfactants, cationic surfactants, and water-soluble polymer dispersants.

(Liquid medium)
Examples of the liquid medium of the plastic working lubricant composition of the present invention include alcohols such as ethanol and methanol, and water such as deionized water and pure water. The plastic working lubricant of the present invention can be added to a liquid medium for use. The liquid medium may contain a liquid medium other than alcohols and water (for example, acetone, ethers). In this case, the liquid medium may be 10% by mass or less based on the total mass of the liquid medium. Is preferred.

Hereinafter, the present invention will be described in more detail based on specific examples. The present invention is not limited to the following examples, and can be implemented with appropriate modifications without departing from the scope of the invention. In addition,% is the mass%.

The average particle diameter, interlayer distance, and thermal decomposition weight loss in Examples and Comparative Examples were measured as follows.

(Average particle size)
Measurement was performed with a laser diffraction particle size distribution analyzer (SALD-2100, manufactured by Shimadzu Corporation).

(Interlayer distance)
It measured using the X-ray-diffraction apparatus (XRD, the Rigaku company make, Ultimate IV). The measurement conditions were: target: Cu, tube voltage: 40 kV, tube current: 40 mA, sampling width: 2θ = 0.02 °, scan speed 2θ = 30 ° / min.

(Pyrolysis weight loss)
The temperature was raised from room temperature to 900 ° C. at an air atmosphere (air flow rate 200 ml / min) and a temperature increase rate of 10 ° C./min using a differential thermothermal gravimetric simultaneous measurement apparatus (EXSTAR TG / DTA6300, manufactured by SII Nano Technologies). The sample amount was about 10 mg. The mass% decreased by raising the temperature from room temperature to 900 ° C. was defined as the organic content.

<Manufacture of solid lubricant>
(Comparative Example 1)
27.64 g of potassium carbonate, 4.91 g of lithium carbonate, and 69.23 g of titanium dioxide were pulverized and mixed by a dry method, and this raw material was calcined at 850 ° C. for 4 hours. The baked sample was immersed in 10 kg of pure water, stirred for 20 hours, separated, washed and dried at 110 ° C. 79.2 L of 10.9% aqueous slurry of the obtained layered titanate was prepared, 4.7 kg of 10% aqueous sulfuric acid solution was added and stirred for 2 hours, and the pH of the slurry was adjusted to 7.0. What was separated and washed with water was dried at 110 ° C. and then calcined at 600 ° C. for 12 hours. The obtained white powder was lithium potassium titanate (K _0.6 Li _0.27 Ti _1.73 O _3.9 ), which is a layered titanate, and had an average particle diameter of 3 μm. The interlayer distance was 7.8 mm. The results are shown in Table 1.

Example 1
65 g of the layered titanate prepared in Comparative Example 1 was dispersed in 5 kg of deionized water, and 150 g of 35% hydrochloric acid was added. After stirring for 1.5 hours, it was separated and washed with water. This operation was repeated three times to obtain layered titanic acid in which K ions and Li ions were exchanged with hydrogen ions or hydronium ions.

50 g of this layered titanic acid was further dispersed in 2 kg of deionized water, heated to 70 ° C., and 104 g of octadecylamine was added with stirring. Stirring was continued for 1 hour and then filtered out. After sufficiently washing with warm water of 70 ° C., the film was dried in air at 40 ° C. for 24 hours. A layered titanic acid compound of the present invention having an average particle size of 5 μm was obtained. The interlayer distance was 57.4 mm by XRD analysis, and it was confirmed that octadecylamine was inserted between the layers. The organic content was 73% by mass due to thermal decomposition loss. The results are shown in Table 2.

(Example 2)
52 g of octadecylamine was dissolved in 2 kg of ethanol, and 50 g of layered titanic acid produced in the same manner as in Example 1 was added thereto with stirring. Stirring was continued at 25 ° C. for 12 hours, and then filtered out. After thoroughly washing with ethanol, it was dried in air at 110 ° C. for 12 hours. A layered titanic acid compound of the present invention having an average particle size of 4 μm was obtained. The interlayer distance was 34.0 mm by XRD analysis, and it was confirmed that octadecylamine was inserted between the layers. The organic content was 51% by mass due to thermal decomposition loss. The results are shown in Table 2.

(Example 3)
65 g of the layered titanate prepared in Comparative Example 1 was dispersed in 1 kg of deionized water, and 25.2 g of 95% sulfuric acid was added. After stirring for 1 hour, it was separated and washed with water. Layered titanic acid obtained by exchanging K ions and Li ions with hydrogen ions or hydronium ions was used. 50 g of this layered titanic acid was dispersed in 2 kg of deionized water, and 139 g of hexadecylpyridinium chloride was added while heating to 70 ° C. and stirring. Stirring was continued for 1 hour and then filtered out. After thoroughly washing with warm water of 70 ° C., it was dried in air at 110 ° C. for 12 hours. A layered titanic acid compound of the present invention having an average particle size of 4 μm was obtained. The interlayer distance was 24.5 mm by XRD analysis, and it was confirmed that hexadecylpyridinium chloride was inserted between the layers. The organic content was 39% by mass due to thermal decomposition loss. The results are shown in Table 2.

(Example 4)
50 g of layered titanic acid synthesized in the same manner as in Example 3 was dispersed in 2 kg of deionized water, and 66 g of benzalkonium chloride was added while heating to 70 ° C. and stirring. Stirring was continued for 1 hour and then filtered out. After thoroughly washing with warm water of 70 ° C., the film was dried in air at 110 ° C. for 12 hours. A layered titanic acid compound of the present invention having an average particle size of 5 μm was obtained. The interlayer distance was 22.7 mm by XRD analysis, and it was confirmed that benzalkonium chloride was inserted between the layers. The organic content was 36% by mass due to thermal decomposition weight loss. The results are shown in Table 2.

(Example 5)
27.64 g of potassium carbonate, 4.91 g of lithium carbonate, and 69.23 g of titanium dioxide were pulverized and mixed by a dry method, and this raw material was calcined at 1000 ° C. for 4 hours. The baked sample was immersed in 10 kg of pure water, stirred for 20 hours, separated, washed and dried at 110 ° C. 79.2 L of 10.9% aqueous slurry of the obtained layered titanate was prepared, 4.7 kg of 10% aqueous sulfuric acid solution was added and stirred for 2 hours, and the pH of the slurry was adjusted to 7.0. What was separated and washed with water was dried at 110 ° C. and then calcined at 600 ° C. for 12 hours. The obtained white powder was lithium potassium titanate (K _0.6 Li _0.27 Ti _1.73 O _3.9 ), which is a layered titanate, and had an average particle diameter of 20 μm. According to XRD analysis, the interlayer distance was 7.8 mm.

65 g of this lithium potassium titanate was dispersed in 5 kg of deionized water, and 150 g of 35% hydrochloric acid was added. After stirring for 1.5 hours, it was separated and washed with water. This operation was repeated three times to obtain layered titanic acid in which K ions and Li ions were exchanged with hydrogen ions or hydronium ions.

50 g of this layered titanic acid was further dispersed in 2 kg of deionized water, heated to 70 ° C., and 104 g of octadecylamine was added with stirring. Stirring was continued for 1 hour and then filtered out. After sufficiently washing with warm water of 70 ° C., the film was dried in air at 40 ° C. for 24 hours. A layered titanic acid compound of the present invention having an average particle size of 21 μm was obtained. The interlayer distance was 58.0 mm by XRD analysis, and it was confirmed that octadecylamine was inserted between the layers. The organic content was 76% by mass due to thermal decomposition loss. The results are shown in Table 2.

(Example 6)
27.64 g of potassium carbonate, 11.66 g of magnesium hydroxide, and 63.91 g of titanium dioxide were pulverized and mixed by a dry method, and this raw material was calcined at 1050 ° C. for 4 hours. The baked sample was immersed in 10 kg of pure water, stirred for 20 hours, separated, washed and dried at 110 ° C. 80 L of 2% aqueous slurry of the obtained layered titanate was prepared, and 189 g of 76% sulfuric acid aqueous solution was added and stirred for 2 hours to adjust the pH of the slurry to 7.5. What was separated and washed with water was dried at 110 ° C. and then calcined at 600 ° C. for 12 hours. The obtained white powder was magnesium potassium titanate (K _0.6 Mg _0.4 Ti _1.6 O _3.9 ), which is a layered titanate, and had an average particle diameter of 5 μm. The interlayer distance was 7.8 mm.

65 g of this magnesium potassium titanate was dispersed in 5 kg of deionized water, and 150 g of 35% hydrochloric acid was added. After stirring for 1.5 hours, it was separated and washed with water. This operation was repeated three times to obtain layered titanic acid in which K ions and Mg ions were exchanged with hydrogen ions or hydronium ions.

50 g of this layered titanic acid was further dispersed in 2 kg of deionized water, heated to 70 ° C., and 104 g of octadecylamine was added with stirring. Stirring was continued for 1 hour and then filtered out. After sufficiently washing with warm water of 70 ° C., the film was dried in air at 40 ° C. for 24 hours. A layered titanic acid compound of the present invention having an average particle size of 5 μm was obtained. The interlayer distance was 58.3 mm by XRD analysis, and it was confirmed that octadecylamine was inserted between the layers. The organic content was 77% by mass due to thermal decomposition loss. The results are shown in Table 2.

(Comparative Example 2)
50 g of layered titanic acid synthesized in the same manner as in Example 1 was dispersed in 2 kg of deionized water, and 17.4 g of ethylamine was added while stirring at 25 ° C. Immediately after the addition, the interlaminar distance swelled so that it could not be measured, and the single layer peeled off rapidly during stirring. Therefore, for Comparative Example 2, the following average friction coefficient is not measured.

Incidentally, the distance between the layers of this dispersion, which was dried, pulverized and powdered, was 9.9 mm.

<Measurement of average friction coefficient of solid lubricant>
The average coefficient of friction when the layered titanate compounds of Examples 1 to 6 and Comparative Example 1 were used as solid lubricants was measured as follows. In addition, the average friction coefficient was measured when boron nitride was used as Comparative Example 3, organic bentonite was used as Comparative Example 4, graphite was used as Comparative Example 5, and molybdenum disulfide was used as Comparative Example 6. Table 1 shows the organic content, interlayer distance, and average particle size of boron nitride, organic bentonite, graphite, and molybdenum disulfide.

The friction coefficient between metals when each powder was used was measured with a pin-on-disk friction tester (TRB manufactured by Antpearl). This testing machine places a weight on the pin shaft, applies a load to the contact part with the disk, rotates the disk, and measures the friction force at this time with a strain gauge provided on the pin side shaft. The friction coefficient obtained by dividing the friction force by the load is output as data. All data is collected via a personal computer. The disk is made of JIS SKH51, thickness is 5 mm, diameter is 20 mm, the pin is made of JIS SUJ2, and the radius of curvature of the tip is 3.175 mm.

The measurement of the friction coefficient was performed for 10 minutes under the conditions of a peripheral speed of 15.7 mm / s (contact radius between the disc and the ball was 3 mm), a load of 1 N, an ambient temperature of 25 ° C., and a relative humidity of 38%. In addition, about 1g of test powder was supplied to the contact part with the cartridge case. The measurement results are shown in Tables 1 and 2.

As shown in Tables 1 and 2, it can be seen that the solid lubricants composed of the layered titanate compounds of Examples 1 to 6 have a lower coefficient of friction than the solid lubricants of Comparative Examples 1, 3, and 4. In addition, it can be seen that the solid lubricants of Examples 1, 2, 5 and 6 have the same or lower friction coefficient as graphite, which is a black solid lubricant.

Further, with respect to Example 1, the result of observing the disk surface after the friction test with a scanning electron microscope is shown in FIG. It was observed that a tribo film was formed on the friction surface. Further, when this tribo film was subjected to elemental analysis using an energy dispersive X-ray analyzer, Ti was detected.

<Manufacture of grease composition>
(Example 7)
5% by mass of the layered titanic acid compound prepared in Example 1, 85% by mass of refined mineral oil, and 10% by mass of lithium soap were mixed, and the mixture was stirred for 5 minutes with a rotation / revolution stirrer (AR-250, manufactured by Shinkey Corp.). A grease composition was prepared by mixing.

(Comparative Example 7)
5% by weight of molybdenum disulfide, 85% by weight of refined mineral oil, and 10% by weight of lithium soap are mixed and stirred for 5 minutes with a rotating and rotating stirrer (AR-250, manufactured by Shinky Corp.) to prepare a grease composition. did.

(Comparative Example 8)
90% by mass of refined mineral oil and 10% by mass of lithium soap were blended, and the mixture was stirred and mixed for 5 minutes with a rotation / revolution stirrer (AR-250, manufactured by Sinky) to prepare a grease composition.

<Fusion load measurement by four ball test of grease composition>
With respect to the grease compositions prepared in Example 7 and Comparative Examples 7 and 8, the fusion load was measured in accordance with ASTM D2596 using a shell type four-ball tester. The results are shown in Table 3.

<Lightness (L value) measurement with a color difference meter of grease composition>
The grease composition prepared in Example 7 and Comparative Examples 7 and 8 was applied to an aluminum plate with a thickness of 2 mm, and a glass plate with a thickness of 1 mm was placed thereon, and a color difference meter (Konica Minolta) was placed thereon. L value (brightness) was measured using CR-300. The results are shown in Table 3. The L value is a numerical value from 0 to 100. A larger number indicates a brighter color, and a smaller number indicates a darker color.

From the results of Table 3, the grease composition (Example 7) containing the solid lubricant of Example 1 has a higher fusion load than the grease composition (Comparative Example 8) not containing the solid lubricant. The same fusion load as that of the grease composition (Comparative Example 7) containing molybdenum disulfide was shown. Further, Comparative Example 7 containing molybdenum disulfide has a low L value and a dark color, whereas Example 7 containing the solid lubricant of the present invention has a high L value and a bright color. I understand.

Further, as is apparent from the evaluation results of the grease composition, the solid lubricant of the present invention can improve the lubricity between metal members, and is also useful as a lubricant composition for plastic working. It turns out that it is a thing.

<Manufacture of lubricant composition for plastic working>
(Example 8)
After dissolving 1 g of polyvinylpyrrolidone K90 (manufactured by Wako Pure Chemical Industries, Ltd.) in 90 g of ethanol at room temperature, 9 g of the layered titanate compound prepared in Example 1 was blended, and 2 roll mills (EXAKT) 2 The lubricant composition for plastic working was prepared by passing through a number of times.

(Comparative Example 9)
1 g of polyvinylpyrrolidone K90 (manufactured by Wako Pure Chemical Industries, Ltd.) is dissolved in 90 g of ethanol at room temperature, 9 g of molybdenum disulfide is blended, and a three-roll mill (manufactured by EXAKT) is passed twice for plastic working. A lubricant composition was prepared.

(Comparative Example 10)
1 g of polyvinylpyrrolidone K90 (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 90 g of ethanol at room temperature, then 9 g of graphite was blended, passed through a three-roll mill (manufactured by EXAKT) twice, and lubricated for plastic working An agent composition was prepared.

(Comparative Example 11)
A lubricant composition for plastic working was prepared by dissolving 1 g of polyvinylpyrrolidone K90 (manufactured by Wako Pure Chemical Industries, Ltd.) in 99 g of ethanol at room temperature.

<Drawing test>
For the drawing test, a hydraulic drawing test machine modified from a 100 kN universal tester was used. Both the punch and die are made of SKD11. The punch has a cylindrical shape with a diameter of 29.2 mm, the corner of the tip has a radius of curvature of 3 mm, the die has a donut shape, an outer diameter of 66 mm, an inner diameter of 30 mm, and the R portion has a radius of curvature of 3 mm. The clearance is 0.4 mm. The workpiece is a stainless steel plate (SUS304 BA), which has a diameter of 60 mm and a thickness of 0.3 mm. Therefore, the aperture ratio is 2.1. The test is performed under the conditions of a punch indentation speed of 0.5 mm / sec and a wrinkle pressing surface pressure of 4 MPa. The lubricant composition for plastic working is uniformly applied to the flange portion, R portion, and straight portion of the die every processing. did. The processing force was measured with a load meter installed in the punch unit to evaluate the workability. Since the smaller the maximum processing force during the test, the lower the load, the higher the workability and the higher the productivity. Also, a frictional force can be obtained by subtracting the deformation resistance force of the material depending on the material from the processing force. Table 4 shows the results of the maximum working force and the maximum friction force of each test.

From the results of Table 4, the plastic working lubricant composition (Example 8) blended with the solid lubricant of Example 1 is the plastic working lubricant composition blended with molybdenum disulfide (Comparative Example 9), graphite. The maximum working force and the maximum frictional force are lower than those of the plastic working lubricant composition (Comparative Example 10) containing no and the plastic working lubricant composition containing no solid lubricant (Comparative Example 11). It was a result. That is, it can be seen that if the lubricant composition for plastic working containing the solid lubricant of Example 1 is used, it can be molded at a low load, and the workability and productivity are high.

Claims

A solid lubricant comprising a layered titanate compound having a layered structure formed by a chain of TiO 6 octahedrons, a cationic organic compound between layers, and an interlayer distance of 10 to 70 mm.
The precursor of the layered titanate compound is a lipid potassium of a lepidoclosite type lithium titanate represented by the general formula K 0.5 to 0.7 Li 0.27 Ti 1.73 O 3.85 to 3.95 The solid lubricant according to claim 1, which is a lipidocrosite-type potassium magnesium titanate represented by the formula K 0.2 to 0.7 Mg 0.4 Ti 1.6 O 3.7 to 3.95 .
3. The solid lubricant according to claim 1, wherein the content of the cationic organic compound is 10 to 99% by mass in 100% by mass of the whole layered titanate compound.
The solid lubricant according to any one of claims 1 to 3, wherein the cationic organic compound is at least one selected from organic ammonium salts, organic phosphonium salts, and organic sulfonium salts.
A grease composition comprising the solid lubricant according to any one of claims 1 to 4, a base oil, and a thickener.
The base oil is mineral oil, gas liquefied oil, diester synthetic oil, aromatic ester synthetic oil, polyol ester synthetic oil, ester synthetic oil, polyglycol synthetic oil, phenyl ether synthetic oil, synthetic hydrocarbon The grease composition according to claim 5, wherein the grease composition is at least one selected from oil, silicone-based synthetic oil, and fluorine-based synthetic oil.
The thickener is alkali metal soap, alkaline earth metal soap, alkali metal composite soap, alkaline earth composite metal soap, alkali metal sulfonate, alkaline earth metal sulfonate, aluminum soap, aluminum composite soap, terephthalate metal salt The grease composition according to claim 5 or 6, which is at least one selected from silica gel, clay, fluorine resin, and urea compound.
A lubricant composition for plastic working, comprising the solid lubricant according to any one of claims 1 to 4.
The lubricant composition for plastic working according to claim 8, further comprising a binder component.
The lubricant composition for plastic working according to claim 9, wherein the binder component is at least one selected from a water-soluble inorganic salt, a water-soluble organic salt, and an organic polymer.
The lubricant composition for plastic working according to any one of claims 8 to 10, further comprising a lubricant component.
12. The lubricant composition for plastic working according to claim 11, wherein the lubricant component is at least one selected from soaps, metal soaps, and waxes.
A method for producing the solid lubricant according to any one of claims 1 to 4,
A step of producing a layered titanic acid by acid treatment of the layered titanate;
And a step of allowing a basic compound or a salt thereof to act on the obtained layered titanic acid.
A method for processing a metal material, wherein the solid lubricant according to any one of claims 1 to 4 is interposed at a friction interface between a workpiece and a processing tool.
A method for processing a metal material, wherein plastic working is performed by interposing the lubricant composition for plastic processing according to any one of claims 8 to 12 at a friction interface between a workpiece and a processing tool.