JP2008195800A - Grease composition and mechanical element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a new grease composition for enabling an elastic fluid lubrication under a high pressure in a high shear field and an excellent lubricating properties on various interfaces while maintaining an excellent thixotropy and lubricating properties. <P>SOLUTION: The grease composition comprises at least one kind of a disklike compound containing a disklike parent nucleus, at least one kind of a thickening agent and a base oil and has a mixture consistency at 40°C of ≤480. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a novel grease composition. More specifically, the present invention relates to a novel grease composition in which the thickener itself has a low friction function.

The current lubricant technology has a mission to achieve both a low friction coefficient and wear resistance, but at the time of start-up and low load, a low coefficient of friction is obtained with a low viscosity base oil. On the other hand, functional sharing has been performed in which wear resistance (which is impaired due to low viscosity base oil) is compensated by boundary lubrication film technology based on the formation of a reactive film on an iron surface. .
However, the situation so far has recently changed dramatically.
One of the causes is downsizing of the apparatus. As devices become smaller, resistance to high temperature, extreme pressure, and high shear conditions is increasingly required. Low-viscosity synthetic oil base oils typified by current mineral oil or PAO (poly-α-olefin) volatilize and decompose at high temperatures, and MoS ₂ which is considered preferable as a boundary lubricating film also decomposes at moisture and high temperatures. To do. Therefore, there is a demand for a lubricant that achieves both boundary lubricity and low friction in a high temperature range from 150 ° C.
Another cause is an increase in environmental awareness. Many of the current boundary lubrication film technologies use environmental hazards (sulfur, phosphorus, halogen) or substances of concern (heavy metals), so ELV (End of Life Vehicles), WEEE (Waste Electrical and Electronic Equipment), Laws such as Restriction of the Use of Certain Hazardous Substances in electrical and electrical equipment (RoHS) have been enacted one after another, and rapid and drastic technical improvements are being sought under the circumstances where environmental awareness is increasing.

  In this situation, we showed a specific low friction property in the elastohydrodynamic lubrication region between the two lubrication regions, as compared to the conventional lubrication technology where fluid lubrication and boundary lubrication dominate. In addition, the present inventors have found and reported a preferable lubricating physical property derived from a specific structure of a disk-like structure molecule that can realize wear resistance under a high load (Non-patent Document 1). In general, in a place where friction occurs in a driven machine, due to the high pressure, ordinary lubricating oil has a viscosity about 1000 times higher. However, discotic molecules with radially soft side chains have a specific viscosity of only a few hundred times, and discotic anisotropic molecules are oriented near the interface in the anisotropic field of shear. As a result, a lower viscosity (Miesowicz due to anisotropic orientation) is obtained, the viscosity increase is suppressed double, and low friction is realized. In principle, this material can exhibit its function only with carbon, hydrogen, and oxygen, and is preferable from the viewpoint of the environment. Several proposals have been made as a lubrication technique using such a discotic structure compound (Patent Documents 1 to 3).

  By the way, the current lubricating oil is basically low-viscosity, which is an indispensable element for lowering the torque at the initial stage of driving, but the grease composition is high-viscosity and can be driven at low torque. . This is due to the thixotropy brought about by the networking of thickeners of metal soap or urea compound kneaded in the lubricant, and the grease composition leaks low-viscosity lubricant outside the sliding part. A low-viscosity lubricating oil containing an extreme pressure agent or the like in the sliding portion is a highly functional composition that exhibits its lubricating function. Therefore, it is an important function for the purpose of lubrication and protection of contact parts between sliding parts such as rolling bearings, slide bearings, sintered bearings, gears, bubbles, cocks, oil seals, electrical contacts, etc., in which lubricating oil cannot be easily replaced. Has been fulfilled.

However, the thickener of this grease composition cannot function for lubricity, that is, low friction, and has an essential problem of the chemical structure that the thickening function is gradually deteriorated by severe shearing. In addition, despite the fact that it is relatively often used for lubrication of resin base materials, the optimum material for lubrication is not selected, but it is an extreme pressure agent used for lubrication of steel base materials. It is only used by adjusting and optimizing the content of (generally an environmental load substance), and a fundamental technological innovation is also required for the grease composition.
FUJIFILM RESEARCH & DEVELOPMENT No. 51 pp80-85 (2006). JP 2002-69472 A Japanese Patent Application Laid-Open No. 2003-192677 JP 2004-331950 A

The present invention provides a novel grease composition that enables elastohydrodynamic lubrication at high pressure, high shear field, and good lubricity at various interfaces while maintaining good thixotropy and lubricity. Let it be an issue.
Another object of the present invention is to provide a machine element that is excellent in low friction and wear resistance and excellent in durability.

式中、Ｄはｍ個の側鎖と結合可能な環状の基を表し、Ｘは各々独立に、単結合、ＮＲ¹基（Ｒ¹は、水素原子又は炭素数が１〜３０のアルキル基）、酸素原子、硫黄原子、カルボニル基、スルホニル基又はこれらの組み合わせからなる二価の連結基を表し、Ｒは各々独立に、置換もしくは無置換の、アルキル基、アルケニル基、アルキニル基、アリール基、複素環基、ハロゲン原子、ヒドロキシ基、アミノ基、メルカプト基、シアノ基、スルフィド基、カルボキシ基もしくはその塩、スルホ基もしくはその塩、ヒドロキシアミノ基、ウレイド基又はウレタン基を表し、ｍは２〜１１の整数を表す。 Means for solving the above-mentioned problems are as follows.
[1] A grease composition containing at least one discotic compound having a discotic mother nucleus, at least one thickener, and a base oil, and having a blending penetration at 40 ° C. of 480 or less.
[2] The grease composition according to [1], wherein at least one of the discotic compounds is a compound represented by the following general formula (1):

In the formula, D represents a cyclic group that can be bonded to m side chains, X is each independently a single bond, NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms). Represents a divalent linking group comprising an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or a combination thereof, and each R is independently a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aryl group, Represents a heterocyclic group, a halogen atom, a hydroxy group, an amino group, a mercapto group, a cyano group, a sulfide group, a carboxy group or a salt thereof, a sulfo group or a salt thereof, a hydroxyamino group, a ureido group, or a urethane group; Represents an integer of 11.

式（２）中、Ａは、５〜７個の原子で構成される環であり、環構成原子の一つ又は二以上が置換基を有していてもよいし、他の環と縮合していてもよく；

式（３）中、Ｂは、５〜７個の原子で構成される環であり、環構成原子の一つ又は二以上が置換基を有していてもよいし、他の環と縮合していてもよい。 [3] The grease composition according to [2], wherein D is a group having a 5- to 7-membered ring structure, or a residue of a porphyrin ring or a phthalocyanine ring.
[4] The grease composition of [2], wherein D is a tautomer group represented by the following general formula (2) or (3):

In formula (2), A is a ring composed of 5 to 7 atoms, and one or two or more of the ring constituent atoms may have a substituent or may be condensed with another ring. May be;

In formula (3), B is a ring composed of 5 to 7 atoms, and one or two or more of the ring constituent atoms may have a substituent or may be condensed with another ring. It may be.

前記式（４）中、Ｚは、各々独立に、酸素原子、硫黄原子、−ＮＲ−のいずれかを表し、互いに同一であっても異なっていてもよく；Ｒは水素原子又は置換基してもよいアルキル基を表す。 [5] The grease composition of [2], wherein D is a group represented by the following general formula (4):

In the formula (4), each Z independently represents any of an oxygen atom, a sulfur atom, and —NR—, and may be the same or different from each other; R is a hydrogen atom or a substituent; Represents a good alkyl group.

式中、Ｘ¹、Ｘ²及びＸ³は各々独立に、単結合、ＮＲ¹基（Ｒ¹は、水素原子又は炭素数が１〜３０のアルキル基）、酸素原子、硫黄原子、カルボニル基、スルホニル基又はこれらの組み合わせからなる二価の連結基を表し、Ｒ¹¹、Ｒ¹²及びＲ¹³は各々独立に、置換もしくは無置換のアルキル基、アルケニル基、アルキニル基、アリール基、ハロゲン原子、ヒドロキシ基、アミノ基、メルカプト基、シアノ基、スルフィド基、カルボキシ基又はその塩、スルホ基又はその塩、ヒドロキヒアミノ基、ウレイド基又はウレタン基を表す。 [6] The grease composition of [2], wherein the discotic compound is a compound represented by the following general formula (5):
General formula (5)

In the formula, X ¹ , X ² and X ³ are each independently a single bond, an NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms), an oxygen atom, a sulfur atom, a carbonyl group, R ¹¹ , R ¹² and R ¹³ each independently represents a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aryl group, halogen atom, hydroxy group, or a divalent linking group comprising a sulfonyl group or a combination thereof. Represents a group, amino group, mercapto group, cyano group, sulfide group, carboxy group or salt thereof, sulfo group or salt thereof, hydroxyamino group, ureido group or urethane group.

式中、Ｘ²¹、Ｘ²²及びＸ²³は、各々独立に、単結合、ＮＲ¹基（Ｒ¹は、水素原子又は炭素数が１〜３０のアルキル基）、酸素原子、硫黄原子、カルボニル基、スルホニル基又はこれらの組み合わせからなる二価の連結基を表し、Ｒ²¹、Ｒ²²及びＲ²³は各々独立に置換基を表す。ａ２１、ａ２２及びａ２３は各々独立して１〜５の整数を表す。 [7] The grease composition of [2], wherein the discotic compound is a compound represented by the following general formula (6):
General formula (6)

In the formula, X ²¹ , X ²² and X ²³ are each independently a single bond, NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms), oxygen atom, sulfur atom, carbonyl group Represents a divalent linking group comprising a sulfonyl group or a combination thereof, and R ²¹ , R ²² and R ²³ each independently represents a substituent. a21, a22 and a23 each independently represents an integer of 1 to 5;

式（７）中、Ａは、５〜７個の原子で構成される環であり、環構成原子の一つ又は二以上が置換基を有していてもよいし、他の環と縮合していてもよく；

式（８）中、Ｂは、５〜７個の原子で構成される環であり、環構成原子の一つ又は二以上が置換基を有していてもよいし、他の環と縮合していてもよい。 [8] The discotic compound has at least one substituent bonded to the discotic mother nucleus, and at least one of the substituents is a tautomeric group or partially includes a tautomeric group. The grease composition according to any one of [1] to [7].
[9] The tautomeric group is a tautomeric group represented by the following general formula (7) or (8), or a ureylene group, a urethane group, an amide group, or a ureido group capable of tautomerization [8] ] Grease composition:

In Formula (7), A is a ring composed of 5 to 7 atoms, and one or two or more of the ring constituent atoms may have a substituent or may be condensed with another ring. May be;

In formula (8), B is a ring composed of 5 to 7 atoms, and one or two or more of the ring constituent atoms may have a substituent or may be condensed with another ring. It may be.

式（９）中、Ｒは独立に、置換基又は非置換基の炭素原子数１〜１８の一価炭化水素基を表し、互いに同一であっても異なっていてもよく；Ｒ¹は独立に炭素原子数１〜６のアルキル基を表し、互いに同一であっても異なっていてもよく；ｘは５〜１２０の整数を表し、ｙは０又は１を表す。 [10] The grease composition according to [8], wherein the tautomeric group is a ureylene group capable of tautomerization.
[11] The discotic compound has at least one substituent bonded to the discotic mother nucleus, and the substituent is or contains an organopolysiloxane group represented by the following general formula (9). [10] Any grease composition:

In formula (9), R independently represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 18 carbon atoms, which may be the same or different from each other; R ¹ independently Represents an alkyl group having 1 to 6 carbon atoms, which may be the same or different; x represents an integer of 5 to 120, and y represents 0 or 1.

式（１０）中、Ｒｆは炭素数１〜１５のパーフルオロアルキル基を表し、ｍ、ｎ、ｐ及びｑは０又は１以上の整数であり、ｍ＋ｎ＋ｐ＋ｑは２〜２００であり；ｒは０又は１であり、ｒが０のときはｓは１で、Ｒｆは炭素数１２以上のパーフルオロアルキル基であり、ｒが１のときはｓは０又は１を表す。 [12] The discotic compound has at least one substituent bonded to the discotic mother nucleus, and the substituent is a polyfluorinated alkyl group or a polyfluorinated alkyl ether group represented by the following general formula (10). The grease composition according to any one of [1] to [11]:

In formula (10), Rf represents a C1-C15 perfluoroalkyl group, m, n, p, and q are 0 or an integer greater than or equal to 1, m + n + p + q is 2-200; r is 0 or When r is 0, s is 1, Rf is a perfluoroalkyl group having 12 or more carbon atoms, and when r is 1, s represents 0 or 1.

式（１１）中、ｎは２以上の整数を表す。 [13] The grease composition according to any one of [1] to [12], wherein the discotic compound has at least one substituent containing an ester bond as a substituent bonded to the discotic mother nucleus.
[14] The [1] to [13], wherein the discotic compound has at least one substituent containing a divalent group represented by the following general formula (11) as a substituent bonded to the discotic nucleus. Any grease composition:

In formula (11), n represents an integer of 2 or more.

式（１２）中、Ｒ²及びＲ³は各々独立に、直鎖又は分枝鎖状パーフルオロアルキル基又はその部分置換体を表し、炭素原子数は１〜２５であり、かつＲ²、Ｒ³のフッ素原子数／炭素原子数の比は０．６〜３である；

式（１３）中、Ｒ⁴、Ｒ⁵及びＲ⁶の一つは水素原子であり、他は各々独立に、直鎖又は分枝鎖状アルキル基を表し、炭素原子数は１〜２６である。 [15] The grease composition according to [11], which contains at least one silicone oil as the base oil.
[16] The grease composition of [12] containing at least one polyfluorinated alkyl ether oil as the base oil.
[17] The grease composition according to any one of [1] to [16], which contains at least one diphenyl ether oil represented by the following general formula (12) or general formula (13) as the base oil:

In the formula (12), R ² and R ³ each independently represents a linear or branched perfluoroalkyl group or a partially substituted product thereof, the number of carbon atoms is 1 to 25, and R ² , R The ratio of the number of fluorine atoms / number of carbon atoms of ³ is 0.6-3;

In the formula (13), one of R ⁴ , R ⁵ and R ⁶ is a hydrogen atom, the other each independently represents a linear or branched alkyl group, and the number of carbon atoms is 1 to 26. .

[18] The grease composition according to any one of [1] to [17], which contains at least one aromatic ester oil having at least three side chains having a carboester group as the base oil.
[19] The grease composition according to any one of [1] to [18], which contains at least one biodegradable oil as the base oil.
[20] The grease composition according to any one of [1] to [19], wherein the base oil contains at least one aromatic ester oil having 6 to 15 carbon atoms in a hydrocarbon group.
[21] The base oil comprises at least (A) an α-alkylstyrene dimer hydride or (B) cyclopentadiene and at least one of an α-olefin and a monovinyl aromatic hydrocarbon. The ratio (ND / CD) of the amount of hydrogen (ND) on the double bond of the norbornene ring to the amount of hydrogen (CD) on the double bond of the cyclopentadiene ring is 0.9. -1.3 Cyclopentadiene fused ring hydrocarbon hydride or (C) saturated hydrocarbon synthesis having in its molecule a cyclic structure of any of cyclohexane, decalin, bicycloheptane and bicyclooctane The grease composition according to any one of [1] to [14], which is a kind selected from hydrocarbons.
[22] The grease composition according to any one of [1] to [21], which contains at least one organic thickener as the thickener.
[23] The grease composition according to any one of [1] to [22], which contains at least one metal soap thickener as the thickener.
[24] The grease composition according to any one of [1] to [23], which contains at least one urea-based thickener as the thickener.
[25] The grease composition according to any one of [1] to [24], which contains at least one inorganic thickener as the thickener.
[26] The grease composition according to any one of [1] to [25], wherein the penetration at 40 ° C is 205 to 395.
[27] The grease composition according to any one of [1] to [26], containing 0.5 to 40% by mass of the discotic compound.
[28] The grease composition according to any one of [1] to [27], containing 5 to 40% by mass of the thickener.
[29] A machine element including at least two surfaces capable of moving at different peripheral speeds and the grease composition according to any one of [1] to [28] disposed between the two surfaces.
[30] The machine element according to [29], wherein at least one of the two surfaces is made of a resin.
[31] The machine element according to [29], wherein at least one of the two surfaces is diamond-like carbon or ceramic.

  According to the present invention, there is provided a novel grease composition that enables elastohydrodynamic lubrication in a high pressure, high shear field and good lubricity at various interfaces while maintaining good thixotropy and lubricity. be able to. Further, according to the present invention, it is possible to provide a machine element that is excellent in low friction and wear resistance and excellent in durability.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described in detail. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.
[Grease composition]
The present invention relates to a grease composition containing at least one discotic compound having a discotic mother nucleus, at least one thickener, and a base oil and having a blending degree at 40 ° C. of 480 or less.

Discotic compounds:
The grease composition of the present invention contains a compound having a disk-shaped mother nucleus, that is, a disk-shaped structure as a partial structure. In the present specification, the “discotic compound” means a compound having a discotic structure as at least a partial structure, and does not require a discotic structure as a whole molecule structure. The morphological characteristics of the disk-like structure can be expressed, for example, as follows for the hydrogen substitution product that is the original compound. First, the molecular size is determined as follows.
1) Construct a molecular structure that is as close to a plane as possible, preferably a planar molecular structure. In this case, as the bond distance and bond angle, it is preferable to use standard values corresponding to the orbital mixture. For example, the Chemical Society of Japan, Chemical Handbook 4th edition, Chapter II, Volume 15 (1993 published by Maruzen) You can refer to it.
2) Using the structure obtained in 1) as an initial value, the structure is optimized by a molecular orbital method or a molecular force field method. Examples of the method include Gaussian 98, MOPAC2000, CHARMm / QUANTA, and MM3, and Gaussian 98 is preferable.
3) The center of gravity of the structure obtained by structure optimization is moved to the origin, and the coordinate axis is taken as the inertial principal axis (the principal axis of the inertia tensor ellipsoid).
4) A sphere defined by the van der Waals radius is given to each atom, thereby describing the shape of the molecule.
5) Measure the length in the direction of each coordinate axis on the van der Waals surface, and let them be a, b and c, respectively.
When a disk-like form is defined using a, b, and c obtained by the above procedure, c ≦ b <a and a / 2 ≦ b ≦ a, preferably c ≦ b <a and 0.7a ≦ b. ≦ a can be expressed. Moreover, it is preferable that b / 2> c.

Specific compounds that serve as the prototype of the disk-like structure are listed in, for example, the Chemical Society of Japan, Quarterly Chemical Review No. 22 “Chemicals of Liquid Crystals”, Chapter 5 and Chapter 10 Section 2 (published in 1994). Destrade et al., Mol. Cryst. Liq. Cryst. 71, 111 (1981), B.R. Kohne et al., Angew. Chem. 96, 70 (1984), J. Am. M.M. Lehn et al. Chem. Soc. Chem. Commun. , 1794 (1985), J. Am. Zhang, J. et al. S. A study report by Moore et al. Am. Chem. Soc. 116, 2655 (1994), and derivatives of the mother nucleus compound. For example, benzene derivative, triphenylene derivative, truxene derivative, phthalocyanine derivative, porphyrin derivative, anthracene derivative, azacrown derivative, cyclohexane derivative, β-diketone metal complex derivative, hexaethynylbenzene derivative, dibenzopyrene derivative, coronene derivative and phenylacetylene macro Cyclic derivatives are mentioned as disk-like structures. Furthermore, the cyclic compounds described in the Chemical Society of Japan, “Chemical Review No. 15 New Aromatic Chemistry” (published by the University of Tokyo Press, 1977) and their electronic structures such as hetero atom substitution can be mentioned.
In addition, as in the case of the metal complex, a plurality of molecules may be formed by a hydrogen bond, a coordinate bond, or the like to form a disk-like molecule. A discotic liquid crystal compound is formed with a structure in which these are used as a mother nucleus at the center of the molecule, and linear alkyl groups, alkoxy groups, substituted benzoyloxy groups, and the like are radially substituted as side chains thereof.

  The discotic compound may be capable of forming a discotic columnar phase or a discotic lamellar phase by aggregating a plurality of molecules thereof. In general, it is not easy to structurally define the constituent molecules of a disc-shaped self-assembly. Subtle three-dimensional structural factors and intermolecular interactions are involved. For example, individual molecules interact with each other through specific or regioselective molecular interactions (a type of molecular recognition) such as hydrogen bonding or metal-metal interactions, and a plurality of molecules form a disk. And a mode in which a disk-like self-organized body is formed by rod-shaped molecules having specificity in the balance of the size and shape of the nonpolar long chain part and the polar core part. For these specific phenomena, see J.A. Chem. Soc. Perkin Trans. 2 1994, 31. And columnar phase formation with oligoethyleneoxyester-based compound oligobodies of trialkoxy gallic acid; Angew. Chem. Int. Ed. Engl. 1995, 34. No. 15.1637. And columnar phase formation by tetraalkoxyphenanthridinone dimer; Liquid Crystals, 1997, Vol. 22, no. 4,427. And columnar phase formation of trialkoxy gallic acid with a glycitol amide compound; Liquid Crystals, 1997, Vol. 22, no. 5,579. And supramolecular liquid crystal formation of barbituric acid; Chem. Mater. 1998, 10, 438. And columnar phase formation by dicarbonyl β-diketonate complexes with rhodium and iridium; and Liquid Crystals, 1998, Vol. 24, no. 3,407. In addition, columnar phase formation by an intramolecular hydrogen-bonded complex of triarylmelamine and aromatic carboxylic acid has been reported respectively. Any material that causes these phenomena, and any material that is presumed to cause a similar phenomenon similar to these materials, can be used as the discotic compound in the grease composition of the present invention. However, J.H. Amer. Chem. Soc. 1997, Vol. 119, no. 18, 4097. Have reported that trialkoxystilbazole trimer of trimellitic acid and phthalimide trimer of melamine do not easily form, and columnar phase formation is caused by subtle structural factors. Suggests that

  The discotic compound has at least two aromatic rings (more preferably a benzene ring), at least one condensed ring (more preferably an aromatic condensed ring, such as a naphthalene ring and a phenanthrene ring) or a π-conjugated plane. It is preferable. The discotic compound is preferably selected from materials exhibiting a liquid crystal phase at normal pressure.

  Preferable examples of the discotic mother nucleus of the discotic compound include structures represented by any one of the following general formulas [1] to [74]. Note that n represents an integer of 3 or more, and * means a site capable of binding to a side chain. However, as long as * is 3 or more, the side chain may not be bonded to all sites. M represents a metal ion or two hydrogen atoms. M represents a metal ion or two hydrogen atoms, that is, [5] and [6] may or may not contain a central metal.

  The mother nucleus preferably has a π-conjugated skeleton containing a polar element. In the above, [1], [2], [3], [4], [5], [6], [9 ], [11], [12], [17], [20], [21], [23], [24], [28], [29], [30], [36], [38], [42], [46], [56], [58], [67], [68], [73], [74] are preferable, and [1], [2], [3], [6] among them are preferable. ], [11], [12], [21], [23], [30], [46], [58], [68], [73] are preferred, and particularly preferably, they can be obtained synthetically and inexpensively. It is a benzene ring of [1] or a 1,3,5-tris (arylamino) -2,4,6-triazine ring of [2].

  The discotic compound preferably has a side chain as a substituent bonded to the discotic nucleus. Examples of the side chain include an alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylthio group, and an acyloxy group. The side chain may contain an aryl group or a heterocyclic group. In addition, C.I. Hansch, A.M. Leo, R.A. W. It may be substituted with a substituent described in Taft, Chemical Review (Chem. Rev.), 1991, Vol. 91, pages 165 to 195 (American Chemical Society). Representative examples include an alkoxy group and an alkyl group. , An alkoxycarbonyl group, and a halogen atom. Further, the side chain may have a functional group such as an ether group, an ester group, a carbonyl group, a cyano group, a thioether group, a sulfoxide group, a sulfonyl group, or an amide group.

More specifically, examples of the side chain moiety include alkanoyloxy groups (eg, hexanoyloxy, heptanoyloxy, octanoyloxy, nonanoyloxy, decanoyloxy, undecanoyloxy), alkylsulfonyl groups (eg, hexyl). Sulfonyl, heptylsulfonyl, octylsulfonyl, nonylsulfonyl, decylsulfonyl, undecylsulfonyl), alkylthio groups (eg, hexylthio, heptylthio, dodecylthio), alkoxy groups (eg, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, Nonyloxy, decyloxy, undecyloxy), 2- (4-alkylphenyl) ethynyl groups (eg, methyl, ethyl, propyl, butyl, pentyl, hexyl as alkyl groups) , Heptyl, octyl, nonyl), terminal ruoxy, 7-vinylheptyloxy, 8-vinyloctyloxy, 9-vinylnonyloxy), 4-alkoxyphenyl groups (for example, those mentioned above as alkoxy groups as alkoxy groups) , An alkoxymethyl group (for example, those mentioned as the alkoxy group described above as an alkoxy group), an alkylthiomethyl group (for example, those mentioned as the alkylthio group described above as an alkylthio group), 2-alkylthiomethyl (eg as an alkylthio group, as described above) In the above-mentioned alkylthio group), 2-alkylthioethoxymethyl (for example, the above-mentioned alkylthio group as an alkylthio group), 2-alkoxyethoxymer group (for example, the above-mentioned alkoxy group as an alkoxy group) ), 2-alkoxy A sulfonylethyl group such as the alkoxy group mentioned above as an alkoxy group), cholesteryloxycarbonyl, β-sitosteryloxycarbonyl, 4-alkoxyphenoxycarbonyl group (eg an alkoxy group mentioned above as an alkoxy group) , 4-alkoxybenzoyloxy group (for example, the above-mentioned alkoxy group as an alkoxy group), 4-alkylbenzoyloxy group (for example, the above-mentioned 2- (4-alkylphenyl) ethynyl group as an alkyl group) ), 4-alkoxybenzoyl groups (for example, those mentioned as the alkoxy group described above as the alkoxy group). Of the above-mentioned compounds, the phenyl group may be another aryl group (for example, naphthyl group, phenanthryl group, anthracene group), or may be further substituted in addition to the above-described substituents. The phenyl group is a heteroaromatic ring (for example, pyridyl group, pyrimidyl group, triazinyl group, thienyl group, furyl group, pyrrolyl group, pyrazolyl group, imidazolyl group, triazolyl group, thiazolyl group, imidazolyl group, oxazolyl group, thiadialyl group. Oxadiazolyl group, quinolyl group, isoquinolyl group).
The number of carbon atoms contained in one side chain is preferably 1 or more and 30 or less, and more preferably 1 or more and 20 or less.

The discotic compound is preferably a compound having a cyclic group having a discotic partial structure and a plurality (preferably 2 to 11) side chains bonded to the cyclic group. At least one of the side chains preferably has an ester bond. In particular, it is preferable that at least one of the side chains includes a group represented by the following general formula (a) or general formula (b). In the following formula, the left side (-X ⁰ ) is bonded to the D side.

General formula (a)

General formula (b)

In the formula, X ⁰ is a single bond, an NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms), an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or a combination thereof. Represents a linking group.
L ⁰ represents an alkylene group (preferably a linear, branched or cyclic alkylene group having 1 to 20 carbon atoms), an NR ¹ group (R ¹ is a hydrogen atom or a carbon number of 1 to 30). An alkyl group), an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or a combination thereof. The divalent linking group may have a substituent. L ⁰ is preferably an alkylene group.
In addition, the group of the combination of X ⁰ and L ⁰ is preferably —O (C═O) -alkylene- or —O (C═O) -cycloalkylene-.
R ⁰ is located at the end of the side chain of the compound and represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.

Further, at least one of the side chains preferably contains an ester bond, and more preferably contains a group represented by the general formula (a). Among these, it is more preferable that the side chain contains a group represented by the following general formula (c). In the following formula, the left side (-L ⁰¹ ) is bonded to the cyclic base side.

Formula (c)

L ⁰¹ is synonymous with X ⁰ . L ⁰¹ is preferably an oxygen atom, a sulfur atom,-(C = O) O-, -NH- (C = O) O-. R ⁰¹ represents a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, and p and q each represents an integer. R ⁰¹ preferably has 1 to 40 carbon atoms, and more preferably 1 to 20 carbon atoms. Substituents include halogen atoms, alkoxy groups (methoxy, ethoxy, methoxyethoxy, phenoxy, etc.), sulfide groups (methylthio, ethylthio, propylthio, etc.), alkylamino groups (methylamino, propylamino, etc.), acyl groups (acetyl, Propanoyl, octanoyl, benzoyl, etc.) and acyloxy groups (acetoxy, pivaloyloxy, banzoyloxy, etc.), aryl groups, heterocyclic groups, hydroxyl groups, mercapto groups, amino groups, cyano groups, nitro groups, carboxyl groups, sulfo groups, carbamoyl groups Group, sulfamoyl group, ureido group and the like. p is preferably from 1 to 20, and more preferably from 2 to 10. q is preferably 1 to 10, and more preferably 1 to 5.

  Moreover, it is also preferable that at least one of the side chains includes a group represented by the following general formula (d) or (e).

General formula (d)

In the formula, R ⁰¹ represents a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, m and n each represent an integer, and represent a group having the same meaning as R ⁰¹ in formula (c).

General formula (e)

In the formula, R ²⁵ represents a substituent, and a24 represents an integer of 1 to 5.

  Moreover, it is also preferable that at least a part of the side chain is a group represented by the following general formula (f).

Formula (f)

In the formula, L ²¹ is a single bond, an NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms), an alkylene group, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or a combination thereof. Represents a divalent linking group consisting of An oxygen atom, an oxyalkylene group, an oxycarbonyl group, an aminocarbonyl group, a carbonyloxy group, and a carbonyl group are preferable, and an oxycarbonyl group and a carbonyl group are more preferable.

Examples of the substituents R ²⁵ , R ⁷¹ and R ⁷² include halogen atoms, alkyl groups (having 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms), alkenyl groups (having 2 to 40 carbon atoms, preferably 2-20), an alkynyl group (having 2 to 40 carbon atoms, preferably 2 to 20 carbon atoms), an aryl group (having 6 to 40 carbon atoms, preferably 6 to 20 carbon atoms), a heterocyclic group (carbon atoms). Cyano group, hydroxyl group, nitro group, carboxyl group, alkoxy group, aryloxy group (having 6 to 40 carbon atoms, preferably 6 to 20), silyloxy A group (having 3 to 40 carbon atoms, preferably 3 to 20), a heterooxy group (having 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms), an acyloxy group (having 2 to 40 carbon atoms, preferably 2-20), carbamo An yloxy group (having 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms), an alkoxycarbonyloxy group (having 2 to 40 carbon atoms, preferably 2 to 20 carbon atoms), an aryloxycarbonyloxy group (having 7 carbon atoms) -40, preferably 7-20, amino group, acylamino group (1-40 carbon atoms, preferably 1-20 carbon atoms), aminocarbonylamino group (1-40 carbon atoms, preferably 1 ˜20), alkoxyaminocarbonylamino group (having 2 to 40 carbon atoms, preferably 2 to 20 carbon atoms), aryloxycarbonylamino group (having 7 to 40 carbon atoms, preferably 7 to 20 carbon atoms), sulfo Famoylamino group (0 to 40 carbon atoms, preferably 0 to 20 carbon atoms), alkyl and arylsulfonylamino groups (1 to 40 carbon atoms, preferably 1 20), a mercapto group, an alkylthio group (having 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms), an arylthio group (having 6 to 40 carbon atoms, preferably 6 to 20 carbon atoms), a heterocyclic thio group ( 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, sulfamoyl groups (0 to 40 carbon atoms, preferably 0 to 20 carbon atoms), sulfo groups, alkyl and arylsulfinyl groups (1 to 40 carbon atoms). , Preferably 1-20, alkyl and arylsulfonyl groups (1-40 carbon atoms, preferably 1-20), acyl groups (1-40 carbon atoms, preferably 1-20 carbon atoms). An aryloxycarbonyl group (having 7 to 40 carbon atoms, preferably 7 to 20 carbon atoms), an alkoxycarbonyl group (having 2 to 40 carbon atoms, preferably 2 to 20 carbon atoms), a carbamoyl group (carbon 1-40 atoms, preferably 1-20 atoms, aryl and heterocyclic azo groups (1-40 carbon atoms, preferably 1-20 atoms), imide groups (4-40 carbon atoms, preferably Is a phosphino group (having 0 to 40 carbon atoms, preferably 0 to 20 carbon atoms), a phosphinyl group (having 0 to 40 carbon atoms, preferably 0 to 20 carbon atoms), a phosphinyloxy group. (0 to 40 carbon atoms, preferably 0 to 20), phosphinylamino group (0 to 40 carbon atoms, preferably 0 to 20 carbon atoms), silyl group (3 to 40 carbon atoms, Preferably 3 to 20). Furthermore, the substituents R ⁷¹ and R ⁷² also include those substituents substituted with one or more substituents selected from these substituents. As the substituent for R ⁷¹ , an alkoxy group, an alkoxycarbonyl group and an acyl group substituted with a substituent containing a linear or branched alkyl group are preferable. a is 0 or an integer of 1 to 5, preferably 1 to 3.
R ⁷¹ preferably has 1 to 40 carbon atoms, more preferably 1 to 20 carbon atoms.

  Moreover, it is also preferable that at least one of the side chains is a fluorocarbon group or contains a fluorocarbon group. The fluorocarbon group may contain a double bond or may contain an aromatic ring. Moreover, any of a linear structure, a branched structure, and a cyclic structure may be sufficient. It is also preferred that at least one of the side chains is a group represented by the following general formula (g).

General formula (g)

In the formula, L ²¹ represents a single bond, an NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms), an alkylene group (preferably a linear or branched chain having 1 to 20 carbon atoms). A divalent linking group comprising an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or a combination thereof. An oxygen atom, an oxyalkylene group, an oxycarbonyl group, an aminocarbonyl group, a carbonyloxy group, and a carbonyl group are preferable, and an oxycarbonyl group and a carbonyl group are more preferable.

Examples of the substituent R ⁸¹ include halogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, heterocyclic groups, cyano groups, hydroxyl groups, nitro groups, carboxyl groups, alkoxy groups, aryloxy groups, silyloxy groups, Heterooxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, amino group, acylamino group, aminocarbonylamino group, alkoxyaminocarbonylamino group, aryloxycarbonylamino group, alphamoylamino group, Alkyl and arylsulfonylamino groups, mercapto groups, alkylthio groups, arylthio groups, heterocyclic thio groups, sulfamoyl groups, sulfo groups, alkyl and arylsulfinyl groups, alkyl and arylsulfonyl groups, acyl Group, an aryloxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an aryl or heterocyclic azo group, an imido group, a phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino group include a silyl group. The preferred carbon number of these groups is the same as the substituents R ²⁵ , R ⁷¹ and R ⁷² . Furthermore, the substituent R ⁸¹ also includes those substituents substituted with one or more substituents selected from these substituents. At least one of a R ⁸¹ is a fluorocarbon group or a substituent containing a fluorocarbon group. The fluorocarbon group may contain a double bond or an aromatic ring. Moreover, any of a linear structure, a branched structure, and a cyclic structure may be sufficient. R ⁸¹ is preferably a partially fluorocarbon group, an alkoxy group, an alkoxycarbonyl group or an acyl group substituted with a substituent containing a linear or branched alkyl group containing a fluorocarbon group. a is 0 or an integer of 1 to 5, preferably 1 to 3.
R ⁸¹ preferably has 1 to 40 carbon atoms, more preferably 1 to 20 carbon atoms.

式（１１）中、ｎは２以上の整数を表す。 The discotic compound may have at least one substituent containing a divalent group represented by the following general formula (11) as a substituent bonded to the discotic mother nucleus.

In formula (11), n represents an integer of 2 or more.

  The discotic compound may have at least one substituent bonded to the discotic mother nucleus, and the substituent may contain an organopolysiloxane group represented by the following general formula (9). The discotic compound is preferably combined with a base oil containing silicone oil.

In formula (9), R independently represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 18 carbon atoms, which may be the same or different from each other; R ¹ independently Represents an alkyl group having 1 to 6 carbon atoms, which may be the same or different; x represents an integer of 5 to 120, and y represents 0 or 1.

  Further, the discotic compound has at least one substituent bonded to the discotic mother nucleus, and the substituent includes a polyfluorinated alkyl group or a polyfluorinated alkyl ether group represented by the following general formula (10). You may go out. Such discotic compounds are preferably combined with base oils including polyfluorinated alkyl ether oils.

  In formula (10), Rf represents a C1-C15 perfluoroalkyl group, m, n, p, and q are 0 or an integer greater than or equal to 1, m + n + p + q is 2-200; r is 0 or When r is 0, s is 1, Rf is a perfluoroalkyl group having 12 or more carbon atoms, and when r is 1, s represents 0 or 1.

  A preferred example of the discotic compound is a compound represented by the following general formula (1).

In the formula, D represents a cyclic group that can be bonded to m side chains, X is each independently a single bond, NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms). Represents a divalent linking group comprising an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or a combination thereof, and each R is independently a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aryl group, It represents a heterocyclic group, a halogen atom, a hydroxy group, an amino group, a mercapto group, a cyano group, a sulfide group, a carboxy group or a salt thereof, a sulfo group or a salt thereof, a hydroxyamino group, a ureido group or a urethane group. m represents an integer of 2 to 11.

In the general formula (1), examples of the cyclic group represented by D include an aromatic group and a heterocyclic group. Examples of the aromatic ring of the aromatic group include a benzene ring, an indene ring, a naphthalene ring, a triphenylene ring, a fluorene ring, a phenanthrene ring, an anthracene ring and a pyrene ring. The aromatic group may have a substituent.
The heterocyclic group preferably has a 5-membered, 6-membered or 7-membered heterocyclic ring. A 5-membered ring or a 6-membered ring is more preferable, and a 6-membered ring is most preferable. As the hetero atom constituting the heterocyclic ring, a nitrogen atom, an oxygen atom and a sulfur atom are preferable. The heterocycle is preferably an aromatic heterocycle. The aromatic heterocycle is generally an unsaturated heterocycle. An unsaturated heterocyclic ring having the most double bond is more preferable. Examples of heterocyclic rings include furan ring, thiophene ring, pyrrole ring, pyrroline ring, pyrrolidine ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, imidazoline ring, imidazolidine ring, pyrazole ring, pyrazoline Ring, pyrazolidine ring, triazole ring, triazane ring, tetrazole ring, pyran ring, pyran ring, thiyne ring, pyridine ring, piperidine ring, oxazine ring, morpholine ring, thiazine ring, pyridazine ring, pyrimidine ring, pyrazine ring, piperazine ring and triazine ring included. A triazine ring is preferred, and a 1,3,5-triazine ring is particularly preferred. Another heterocyclic ring, an aliphatic ring or an aromatic ring may be condensed with the heterocyclic ring. However, monocyclic heterocycles are preferred.

In the general formula (1), X is a single bond, NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms), oxygen atom, sulfur atom, carbonyl group, sulfonyl group, or a combination thereof. Represents a divalent linking group consisting of When X is a single bond, it may be directly bonded with a nitrogen atom having a free valence such as piperidine in a heterocyclic group, and further bonded with a heteroatom without a free valence, and an oxonium salt or a sulfonium salt An onium salt may be formed like an ammonium salt. X in the general formula (1) is preferably a sulfur atom or an NR ¹ group, and R ¹ is preferably an alkyl group having 3 or less carbon atoms or a hydrogen atom.

In the general formula (1), when R is an alkyl group, the number of carbon atoms is preferably 1-30, more preferably 2-30, and even more preferably 4-30, 30 is most preferred. The alkyl group may be linear or branched. Moreover, you may have a substituent. Examples of substituents include halogen atoms, alkoxy groups (methoxy, ethoxy, methoxyethoxy, phenoxy, etc.), sulfide groups (methylthio, ethylthio, propylthio, etc.), alkylamino groups (methylamino, propylamino, etc.), acyl groups ( Acetyl, propanoyl, octanoyl, benzoyl, etc.) and acyloxy groups (acetoxy, pivaloyloxy, benzoyloxy, etc.), hydroxyl groups, mercapto groups, amino groups, carboxyl groups, sulfo groups, carbamoyl groups, sulfamoyl groups, and ureido groups.
In general formula (1), R represents an alkenyl group and the alkynyl group has the same carbon number and shape as the alkyl group, and may have the same substituent.

  In the general formula (1), when R is an aryl group, examples thereof include a phenyl group, an indenyl group, an α-naphthyl group, a β-naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, and a pyrenyl group. Group and naphthyl group are preferred. Furthermore, you may have a substituent. Examples of the substituent include those exemplified above for the substituent of the alkyl group, as well as an alkyl group. The substituent includes a linear or branched alkyl group having 8 or more carbon atoms, such as an alkyl group (octyl). Decyl, hexadecyl, 2-ethylhexyl, etc.), alkoxy groups (dodecyloxy, hexadecyloxy, etc.), sulfide groups (hexadecylthio, etc.), substituted amino groups (heptadecylamino, etc.), octylcarbamoyl groups, octanoyl groups, and decylsulfa It is preferably substituted with a moyl group or the like. These substituents are preferably substituted at least two, and in addition to the above substituents, they are substituted with halogen atoms, hydroxyl groups, cyano groups, nitro groups, carboxyl groups, sulfo groups, etc. May be.

  In the general formula (1), when R is a heterocyclic group, like D, a heterocyclic group having a 5- to 7-membered ring structure is preferable, a 5-membered ring or a 6-membered ring is more preferable, and a 6-membered ring is Most preferred. Specific examples of these skeletons are also included in Appendix 11 of the Iwanami Physics and Chemistry Dictionary 3rd edition (published by Iwanami Shoten). Names of major heteromonocyclic compounds page 1606 and Table 5. Names of main condensed heterocyclic compounds The compounds described on page 1607 are listed. Further, like the aryl group, these may have a substituent and are preferably substituted with a substituent containing a linear or branched alkyl group having 8 or more carbon atoms. These substituents are preferably substituted at least two, and in addition to the above substituents, they are substituted with halogen atoms, hydroxyl groups, cyano groups, nitro groups, carboxyl groups, sulfo groups, etc. May be.

At least one of R preferably has an ester bond, more preferably an alkoxy group substituted with a substituent containing a linear or branched alkyl group containing an ester bond. . Further, it is more preferable that all of R include an ester bond, and it is further preferable that all of them are alkoxy groups substituted with a substituent containing a linear or branched alkyl group containing an ester bond. More preferred. That is, at least one of R preferably contains a group represented by the formula (4a) or (4b), and a group represented by any one of the formulas (4) to (6). More preferably.
In addition, at least one of R—X— is preferably a group represented by the general formula (7) or (8), and all the groups represented by the general formula (7) or (8). It is also more preferable.

  Among the compounds represented by the general formula (1), compounds represented by the following general formula (2) are preferable.

In the formula, X ¹ , X ² and X ³ are each independently a single bond, an NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms), an oxygen atom, a sulfur atom, a carbonyl group, Represents a divalent linking group comprising a sulfonyl group or a combination thereof. When X ¹ , X ² , and X ³ are single bonds, they may be directly bonded with a nitrogen atom having a free valence such as piperidine as a heterocyclic group, and further bonded with a hetero atom even if there is no free valence. In addition, an onium salt may be formed such as an oxonium salt, a sulfonium salt, or an ammonium salt. X ¹ , X ² , and X ³ are each an NR ¹ group (R ¹ is an alkyl group having 1 to 30 carbon atoms or a hydrogen atom), an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or these when not a single bond A divalent linking group consisting of a combination of, for example, oxycarbonyl group, aminocarbonyl group, ureylene group, oxysulfonyl group, sulfamoyl group and the like. A sulfur atom or an NR ¹ group is preferred, and R ¹ is preferably an alkyl group having 3 or less carbon atoms or a hydrogen atom. In this, an imino group (-NH-) is more preferable.

In the general formula (2), R ¹¹ , R ¹² and R ¹³ are each independently a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aryl group or heterocyclic group, halogen atom, hydroxy group, An amino group, a mercapto group, a cyano group, a sulfide group, a carboxy group or a salt thereof, a sulfo group or a salt thereof, a hydroxyamino group, a ureido group, or a urethane group.

The alkyl groups represented by R ¹¹ , R ¹² and R ¹³ each have 1 to 30 carbon atoms, preferably 2 to 30 carbon atoms, more preferably 4 to 30 carbon atoms, and 6 to 30 carbon atoms. Most preferred. The alkyl group may be linear or branched. Moreover, you may have a substituent. Examples of substituents include halogen atoms, alkoxy groups (methoxy, ethoxy, methoxyethoxy, phenoxy, etc.), sulfide groups (methylthio, ethylthio, propylthio, etc.), alkylamino groups (methylamino, propylamino, etc.), acyl groups ( Acetyl, propanoyl, octanoyl, benzoyl, etc.) and acyloxy groups (acetoxy, pivaloyloxy, benzoyloxy, etc.), hydroxyl groups, mercapto groups, amino groups, carboxyl groups, sulfo groups, carbamoyl groups, sulfamoyl groups, and ureido groups. R ¹¹ , R ¹² , and R ¹³ are alkenyl and alkynyl groups having the same carbon number and shape as the alkyl group, and may have the same substituent.

Examples of the aryl groups represented by R ¹¹ , R ¹² and R ¹³ include phenyl group, indenyl group, α-naphthyl group, β-naphthyl group, fluorenyl group, phenanthrenyl group, anthracenyl group and pyrenyl group. A phenyl group or a naphthyl group is preferred. Further, a substituent containing a linear or branched alkyl group having 8 or more carbon atoms, such as an alkyl group (octyl, decyl, hexadecyl, 2-ethylhexyl, etc.), an alkoxy group (dodecyloxy, hexadecyloxy, 2- Hexyldecyloxy, hexyloxyethyleneoxyethyleneoxy, etc.), sulfide groups (hexadecylthio, etc.), substituted amino groups (heptadecylamino, etc.), octylcarbamoyl groups, octanoyl groups, decylsulfamoyl groups, etc. . These substituents are preferably substituted at least two, and in addition to the above substituents, they are substituted with halogen atoms, hydroxyl groups, cyano groups, nitro groups, carboxyl groups, sulfo groups, etc. May be.

In the heterocyclic group represented by each of R ¹¹ , R ¹² and R ¹³ , a heterocyclic residue having a 5- to 7-membered ring structure is preferable, like D in the general formula (1). Is more preferable, and a 6-membered ring is most preferable. Specific examples of these skeletons are also included in Appendix 11 of the Iwanami Physics and Chemistry Dictionary 3rd edition (published by Iwanami Shoten). Names of major heteromonocyclic compounds page 1606 and Table 5. Examples include the compounds described on page 1607 of the name of the main condensed heterocyclic compound. Further, like the aryl group, these are preferably substituted with a substituent containing a linear or branched alkyl group having 8 or more carbon atoms. These substituents are preferably substituted at least two, and in addition to the above substituents, they are substituted with halogen atoms, hydroxyl groups, cyano groups, nitro groups, carboxyl groups, sulfo groups, etc. May be.

At least one of R ¹¹ , R ¹² and R ¹³ preferably has an ester bond, and alkoxy substituted with a substituent containing a linear or branched alkyl group containing an ester bond More preferably, it is a group. Further, it is more preferable that all of R ¹¹ , R ¹² and R ¹³ contain an ester bond, and all of them are substituted with a substituent containing a linear or branched alkyl group containing an ester bond. Even more preferred is an alkoxy group. That is, at least one of R ¹¹ , R ¹² and R ¹³ preferably contains a group represented by the formula (a) or (b), and any one of the formulas (c) to (e) It is more preferable that a group represented by
It is also preferred that at least one of R ¹¹ —X ¹ —, R ¹² —X ² — and R ¹³ —X ³ — is a group represented by the general formula (f) or (g), It is also more preferable that it is group represented by general formula (f) or (g).

  Furthermore, the compound represented by the following general formula (3) is mentioned as a more preferable aspect of the compound represented by the said General formula (2).

In the formula, X ²¹ , X ²² and X ²³ are each independently a single bond, NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms), oxygen atom, sulfur atom, carbonyl group Represents a divalent linking group comprising a sulfonyl group or a combination thereof. When X ²¹ , X ²² , and X ²³ are single bonds, they may be directly bonded with a nitrogen atom having a free valence such as piperidine as a heterocyclic group, and further bonded with a hetero atom even if there is no free valence. In addition, an onium salt may be formed such as an oxonium salt, a sulfonium salt, or an ammonium salt. When X ²¹ , X ²² , and X ²³ are not a single bond, an NR ¹ group (R ¹ is an alkyl group having 1 to 30 carbon atoms or a hydrogen atom), an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or these It represents a divalent linking group composed of a combination, for example, an oxycarbonyl group, an aminocarbonyl group, a ureylene group, an oxysulfonyl group, a sulfamoyl group, and the like. X ²¹ , X ²² and X ²³ are preferably a sulfur atom or an NR ¹ group, and R ¹ is preferably an alkyl group having 3 or less carbon atoms or a hydrogen atom. In this, an imino group (-NH-) is more preferable.

In the formula, R ²¹ , R ²² and R ²³ each independently represents a substituent. Substituents R ²¹ , R ²² and R ²³
Is a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxyl group, nitro group, carboxyl group, alkoxy group, aryloxy group, silyloxy group, heterooxy group, acyloxy group, carbamoyl Oxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, amino group, acylamino group, aminocarbonylamino group, alkoxyaminocarbonylamino group, aryloxycarbonylamino group, alphamoylamino group, alkyl and arylsulfonylamino group, mercapto Group, alkylthio group, arylthio group, heterocyclic thio group, sulfamoyl group, sulfo group, alkyl and arylsulfinyl group, alkyl and arylsulfonyl group, acyl group, aryl group Aryloxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an aryl or heterocyclic azo group, an imido group, a phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino group include a silyl group. The preferred carbon number of these groups is the same as the substituents R ²⁵ , R ⁷¹ and R ⁷² . Furthermore, the substituents R ²¹ , R ²² and R ²³ include those substituents substituted with one or more substituents selected from these substituents.

At least one of R ²¹ , R ²² and R ²³ preferably has an ester bond, and alkoxy substituted with a substituent containing a linear or branched alkyl group containing an ester bond More preferably, it is a group. Further, it is more preferable that all of R ²¹ , R ²² and R ²³ contain an ester bond, and all of them are substituted with a substituent containing a linear or branched alkyl group containing an ester bond. Even more preferred is an alkoxy group. That is, at least one of R ²¹ , R ²² and R ²³ preferably contains a group represented by the formula (a) or (b), and any one of the formulas (c) to (e) It is more preferable that a group represented by
Further, in the formula _{^{(R 21) a21 -Ph-X}} 21 -, (R 22) a22 -Ph-X 22 - and _{^{R 23) a23 -Ph-X 23}} - is at least one of the general formula (f ) Or (g) is also preferred, and it is more preferred that all are groups represented by the general formula (f) or (g).

  In the formula, a21, a22 and a23 each independently represents an integer of 1 to 5.

  The discotic compound preferably has a tautomeric group. The tautomeric group may be contained in the discotic mother nucleus (D in the general formula (1)) or may be contained in a chain-like substituent bonded to the discotic mother nucleus. Here, tautomerism will be described. An isomerism phenomenon in which a compound exists as two kinds of isomers and they easily change is called tautomerism, and each isomer is called a tautomer. The tautomeric group possessed by the discotic compound is preferably a tautomeric group represented by the following general formula (2) or (3).

  In formula (2), A is a ring composed of 5 to 7 atoms, and one or two or more of the ring constituent atoms may have a substituent or may be condensed with another ring. It may be. When A is condensed with another ring, the other ring may have a substituent.

  In formula (3), B is a ring composed of 5 to 7 atoms, and one or two or more of the ring constituent atoms may have a substituent or may be condensed with another ring. It may be. When B is condensed with another ring, the other ring may have a substituent.

  Among these, a tautomeric group represented by the following general formula (4), which is an example of the tautomeric group represented by the general formula (2), is preferable.

  In the formula (4), each Z independently represents any of an oxygen atom, a sulfur atom, and —NR—, and may be the same or different from each other; R is a hydrogen atom or a substituent Represents an optionally substituted alkyl group.

  Most changes between two tautomers of a tautomeric group occur by changing the bonding position of a hydrogen atom. Such tautomeric functional groups may be bonded to other compounds having the same tautomeric structure, for example, the same amidine structure or keto-enol tautomers (carbamoyl group, carboxyl group) through hydrogen bonding. Thus, a relatively stable complex structure is formed. For example, the tautomeric group represented by the general formula (2) forms a complex with an amidino group, a carbamoyl group, and a carboxyl group by hydrogen bonding as shown in the following general formulas (2a) to (2c).

  A typical example is a base pair formed by hydrogen bonding between a purine base and a pyrimidine base constituting nucleic acids (DNA and RNA).

The normal base pairs in DNA are the base pair between the purine base adenine (A) and the pyrimidine base thymine (T), and the base pair between the purine base guanine (G) and the pyrimidine base cytosine (C). As shown in the figure, the former is stabilized by two hydrogen bonds and the latter by three hydrogen bonds. Such a base pair is called a complementary base pair and forms a hydrogen bond while maintaining planarity. Therefore, in the case of a planar discotic compound, the planarity is expected to be widely formed supramolecularly. Is done.
The discotic compound having a tautomer group, for example, a 1,3,5-trianilino-2,4,6-triazine derivative, is a cyanuric acid, a melamine, an adenine, a guanine, a cytosine, a thymine or a derivative thereof. Since similar complementary base pairs can be formed through heterocyclic compounds such as tool acids and uracils, the use of such compounds in combination as thickeners effectively forms a network and is highly enriched against base oils. It is thought that an effect is expressed.
In addition, the addition amount of the thickener that forms a complementary base pair together with the discotic compound should be added in the range of 1 to 500 mol% with respect to the discotic compound having such a tautomeric group. Is preferable, and the range of 10 to 200 mol% is more preferable.

  In particular, in a grease composition using a discotic mother nucleus or a discotic compound having a tautomer group in its side chain together with a urea-based thickener, low friction is obtained even if the content of the discotic compound is relatively small. It was found that the coefficient tends to be obtained. This is because the disk-like compound dissolved in the base oil is aggregated by the above-described hydrogen bonds with the ureylene group of the thickener urea, so that it is supplied to the frictional shear field more than the state dissolved in the base oil. I guess that is improving.

  Specific examples of the tautomeric group represented by the general formula (2) or (3) are shown below, but are not limited thereto.

  When the oligoethyleneoxy group is substituted at a position closer to a tautomer capable of forming a hydrogen bond, the thermal stability of the hydrogen bond is improved. Among these, a tetraethyleneoxy group or higher oligoethyleneoxy group is preferable.

  The discotic compound preferably has at least three chain substituents together with the tautomeric group. The chain substituent is preferably substituted with a ring constituting the discotic structure of the discotic compound, and the chain substituent is preferably substituted radially with the ring as a center. . For example, when the ring constituting the discotic structure is a 6-membered ring, the chain substituent is preferably substituted with atoms at the 1-position, 3-position and 5-position. Further, when the ring constituting the disc-like structure is a 1,3,5-triazine ring, the chain substituent is substituted with carbon atoms at positions 2, 4, and 6. preferable. When the tautomeric group represented by the general formula (1) is a ring constituting a discotic structure, the chain substituent is directly connected to the ring-constituting atom or NH- in the formula, or It may be bonded via a linking group.

The chain substituent is a chain substituent formed by bonding 5 or more atoms in a chain (for example, in the case of an alkyl group, a C ₅ or more normal alkyl group or the like, in the case of an alkoxy group, C _An alkoxy group containing ₄ or more normal alkyl chains and the like is preferable. Examples of the chain substituent include an alkyl group, an alkoxy group, an aryloxy group, an alkoxycarbonyl group, an alkylthio group, an arylthio group, an alkylimino group, an arylimino group, and an acyloxy group. These chain substituents may contain cyclic groups such as aryl groups and heterocyclic groups as long as they have a chain partial structure in which 5 or more atoms are bonded in a chain. In addition, C.I. Hansch, A.M. Leo, R.A. W. It may be substituted with a substituent described in Taft, Chemical Review (Chem. Rev.), 1991, Vol. 91, pages 165 to 195 (American Chemical Society). Representative examples include an alkoxy group and an alkyl group. , An alkoxycarbonyl group, and a halogen atom. Further, the chain substituent may have a functional group such as an ether group, an ester group, a carbonyl group, a cyano group, a thioether group, a sulfoxide group, a sulfonyl group, or an amide group.

  More specifically, examples of the chain substituent include an alkanoyloxy group (for example, hexanoyloxy, heptanoyloxy, octanoyloxy, nonanoyloxy, decanoyloxy, undecanoyloxy), an alkylsulfonyl group (for example, , Hexylsulfonyl, heptylsulfonyl, octylsulfonyl, nonylsulfonyl, decylsulfonyl, undecylsulfonyl), alkylthio group (for example, hexylthio, heptylthio, dodecylthio), arylthio group (for example, 3,4-dialkoxy-substituted phenylthio group, alkoxy group) As mentioned above for alkoxy groups), alkoxy groups (for example, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy, decyloxy, undecyl) Oxy, methoxyethoxy, ethoxyethoxy, methoxydiethyleneoxy, triethyleneoxy, hexyloxydiethyleneoxy), aryloxy groups (for example, 3,4-dialkoxy-substituted phenyloxy groups, alkoxy groups are mentioned in the above alkoxy groups. ), Alkylamino groups (for example, butylamino, pentylamino, hexylamino, heptylamino, octylamino, nonylamino, decylmino, undecylamino, methoxyethylamino, ethoxyethylamino, methoxydiethyleneamino, triethyleneamino, hexyl) Oxydiethyleneamino), arylamino groups (for example, 3,4-dialkoxy-substituted phenylamino groups, alkoxy groups as mentioned above for alkoxy groups), 2- (4-alkyl groups) Nyl) ethynyl group (for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl as alkyl group), 2- (4-alkoxyphenyl) ethynyl group (for example, alkoxy group as described above with alkoxy group) Terminal vinyloxy (e.g., 7-vinylheptyloxy, 8-vinyloctyloxy, 9-vinylnonyloxy), 4-alkoxyphenyl group (e.g., those mentioned above as alkoxy groups as alkoxy groups), An alkoxymethyl group (for example, those mentioned as the alkoxy group as mentioned above), an alkylthiomethyl group (eg as mentioned as the alkylthio group mentioned above as the alkylthio group), 2-alkylthiomethyl (eg as the alkylthio group mentioned above as Also listed as alkylthio group ), 2-alkylthioethoxymethyl (for example, those mentioned for the alkylthio group as the alkylthio group), 2-alkoxyethoxyethyl groups (for example, those mentioned for the alkoxy group as the alkoxy group), 2-alkoxycarbonyl An ethyl group, for example, an alkoxy group as mentioned above for the alkoxy group), cholesteryloxycarbonyl, β-sitosteryloxycarbonyl, 4-alkoxyphenoxycarbonyl group (for example, an alkoxy group as mentioned for the alkoxy group above), 4-alkoxybenzoyloxy groups (for example, those mentioned for the alkoxy group as the alkoxy group), 4-alkylbenzoyloxy groups (for example, those for the alkoxy group mentioned above for the 2- (4-alkylphenyl) ethynyl group) ), 4-A Kokishibenzoiru group (as for example, an alkoxy group, those mentioned alkoxy group described above), perfluoroalkyl group (e.g., alkyl group, those mentioned in the above-described alkyl groups), a polysiloxane group.

  Of the above-mentioned compounds, the phenyl group may be another aryl group (for example, naphthyl group, phenanthryl group, anthracene group), or may be further substituted in addition to the above-described substituents. The phenyl group is a heteroaromatic ring (for example, pyridyl group, pyrimidyl group, triazinyl group, thienyl group, furyl group, pyrrolyl group, pyrazolyl group, imidazolyl group, triazolyl group, thiazolyl group, imidazolyl group, oxazolyl group, thiadialyl group. Oxadiazolyl group, quinolyl group, isoquinolyl group).

  1-30 are preferable and, as for the number of the carbon atoms contained in one chain substituent, 1-20 are more preferable.

  From the viewpoint of forming a complementary base pair with a functional group such as a carboxyl group present on each face of the discotic compound molecule, the pKa of the imino group contained in the tautomeric group is relatively small. Is preferred. In order to reduce the pKa of the imino group, the ring A is preferably electron-deficient, is composed of an element having a high electronegativity, and the ring A is preferably electron-withdrawing. Therefore, in general, when other substituents are the same, a triazine ring is preferable to a pyridine ring.

  A preferred example of the discotic compound is a 1,3,5-trisubstituted triazine compound represented by the following general formula (2 ').

General formula (2 ')

In the formula, each Z independently represents any of —O—, —S—, and —NR— (wherein R represents a hydrogen atom or an alkyl group of C ₁₀ or less), and may be the same as or different from each other. Preferably, at least one represents -NH-. R ¹ each independently represents a substituent, which may be the same or different from each other, but at least two of them are aromatic having a chain substituent formed by bonding 5 or more atoms in a chain. A substituent containing a ring group.

  Examples of the chain-like substituent include an alkyl group (for example, butyl, hexyl, octyl, lauryl), a substituted alkyl group (for example, 2-ethylhexyl, 3-hexyldecyl, methoxyethoxyethyl, ethyliminoethyliminoethyl, ethyl). Thioethyl, butoxycarbonylethyl, cyclohexylcarbamoylmethyl, morpholinoethyl, N, N-dimethylaminoethyl, vinyloxypropyl, propargyloxyethyl), perfluoroalkyl groups (eg, perfluorobutyl, perfluoroether), borosiloxy groups Is mentioned.

Examples of the aromatic ring having a chain-like substituent include those having a six-membered ring structure such as a benzene ring and a cyclohexane ring; those having a direct ring structure such as biphenyl and terphenyl; Rings linked via a linking group, such as benzene or foxaphenylethynylbenzene; condensed rings such as naphthalene, quinoline, anthracene, triphenylene, pyrene; heterocycles containing nitrogen, oxygen, or sulfur elements in the ring Examples thereof include furan, thiophene, pyrrole, oxazole, thiazole, imidazole, triazole, tetrazole and their benzene condensed rings, pyridine, pyrimidine, pyrazine, quinoline and the like, which are composed of rings.
Examples of the chain substituent by linking at least 5 elements include the chain substituents described above.

  Specific examples of the discotic compound that can be used in the present invention are listed below, but the present invention is not limited thereto.

  The grease composition of the present invention may contain two or more organic compounds having a discotic mother nucleus, preferably a mesogenic structure, in the molecule. In such a case, a plurality of types of organic compounds having the same mesogenic structure and different side chains may be used. Moreover, the said lubricant composition may contain the organic compound which reduces the liquid crystal phase formation temperature with the said organic compound. As a combination of such compounds at normal pressure, non-patent literature Mol. Cryst. Liq. Cryst. , 1981, Vol. 71, pp111. FIG. To FIG. And the compounds described in Japanese Patent Application Laid-Open No. 9-104866. As described in the references, there are few descriptions regarding the combination of such compounds, but there is no chemical structure particularly excluded or restricted structurally, and as a structure that lowers the liquid crystal phase formation temperature more efficiently. , Having a structure similar to the side chain of the liquid crystal compound used, preferably a compound containing at least one polar functional group such as an ether group or a carbonyl group, such as an ether containing an oligoethyleneoxy group and an alkyl group having 6 or more carbon atoms The following specific compound examples, such as a compound and an ester compound, are mentioned.

  The content of the discotic compound in the grease composition of the present invention is preferably 0.1 to 40% by mass, more preferably 0.5 to 10% by mass, and 1.0 to 5. It is still more preferable that it is 0 mass%.

Thickener:
The grease composition of the present invention contains at least one thickener. Examples of thickeners used in the present invention include soap-type thickeners such as metal soaps and composite metal soaps; and benton, silica gel, urea-type thickeners (urea compounds, urea-urethane compounds, urethane compounds, etc.) And any non-soap thickener. Among these, a soap-based thickener and a urea-based thickener are preferably used because they are less likely to damage the resin member.

  Examples of the soap-based thickener include sodium soap, calcium soap, aluminum soap, and lithium soap. Among these, lithium soap is preferable from the viewpoint of water resistance and thermal stability. Examples of lithium soap include lithium stearate and lithium-12-hydroxystearate.

  Examples of urea thickeners include urea compounds, urea / urethane compounds, urethane compounds, and mixtures thereof.

  Examples of urea compounds, urea / urethane compounds and urethane compounds include diurea compounds, triurea compounds, tetraurea compounds, polyurea compounds (excluding diurea compounds, triurea compounds and tetraurea compounds), urea / urethane compounds, diurethane compounds or mixtures thereof. Etc. Preferably, a diurea compound, a urea / urethane compound, a diurethane compound or a mixture thereof is used. More specifically, for example, a compound represented by the following formula (X-1) alone or a mixed system thereof is preferable.

^{A-CONH-R 1 -NHCO-} B (X-1)
In general formula (X-1), R ¹ represents a divalent organic group, preferably a divalent hydrocarbon group. Specific examples of the divalent hydrocarbon group include a linear or branched alkylene group, a linear or branched alkenylene group, a cycloalkylene group, an arylene group, an alkylarylene group, an arylalkylene group, and the like. Is mentioned. The carbon number of the divalent organic group represented by R ¹ is preferably 6 to 20, and more preferably 6 to 15.

Preferred examples of the divalent organic group represented by R ¹ include an ethylene group, a 2,2-dimethyl-4-methylhexylene group, and the following formulas (X-2) to (X-11). Among them, the group represented by the formula (X-3) or (X-5) is preferable.

(X-2)

(X-3)

(X-4)

(X-5)

(X-6)

(X-7)

(X-8)

(X-9)

(X-10)

In general formula (X-1), A and B may be the same or different and each represents a group represented by —NHR ² , —NR ³ R ⁴ or —OR ⁵ . Here, R ² , R ³ , R ⁴ and R ⁵ may be the same or different and each is a monovalent organic group, preferably a monovalent hydrocarbon group having 6 to 20 carbon atoms.

Examples of the monovalent hydrocarbon group having 6 to 20 carbon atoms represented by R ² , R ³ , R ⁴ , and R ⁵ include a straight chain or branched alkyl group, a straight chain or branched alkenyl. Group, cycloalkyl group, alkylcycloalkyl group, aryl group, alkylaryl group, arylalkyl group and the like. More specifically, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl Linear or branched alkyl groups such as: hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecenyl Straight chain or branched alkenyl groups such as eicocenyl group; cyclohexyl group; methylcyclohexyl group, dimethylcyclohexyl group, ethylcyclohexyl group, diethylcyclohexyl group, propylcyclohexyl group, isopropylcyclohexyl group Sil group, 1-methyl-3-propyl cyclohexyl group, butyl cyclohexyl group, amyl cyclohexyl group, amyl methyl cyclohexyl group, hexyl cyclohexyl group, heptyl cyclohexyl group, octyl cyclohexyl group, nonyl cyclohexyl group, decyl cyclohexyl group, undecyl cyclohexyl group Alkylcycloalkyl groups such as dodecylcyclohexyl group, tridecylcyclohexyl group and tetradecylcyclohexyl group; aryl groups such as phenyl group and naphthyl group; toluyl group, ethylphenyl group, xylyl group, propylphenyl group, cumenyl group and methylnaphthyl group Alkylaryl groups such as ethyl naphthyl group, dimethyl naphthyl group and propyl naphthyl group; aryls such as benzyl group, methylbenzyl group and ethylbenzyl group Alkyl group, etc. Among these, from the viewpoint of heat resistance and acoustic anti-, alkyl group, cycloalkyl group, alkylcycloalkyl group, an aryl group and an alkylaryl group.

The compound represented by the general formula (X-1) is, for example, a diisocyanate represented by OCN—R ¹ —NCO and a compound represented by R ² NH ₂ , R ³ R ⁴ NH or R ⁵ OH, or these Is reacted at 10 to 200 ° C. in a base oil. Incidentally, R ¹ in the formula representing the starting ^{compound, R 2, R 3, R} 4, R 5 are, according to the respective compounds represented by the general formula ^{(X-1) R 1,} R 2, R 3, R ⁴ , synonymous with R ⁵ .

  In the grease composition of the present invention, the content of the thickener is preferably 40% by mass or less. More preferably, it is 3 mass% or more, More preferably, it is 5 mass% or more, More preferably, it is 10 mass% or more. If the content of the thickener is less than 3% by mass, the effect of adding the thickener becomes insufficient, and it becomes difficult to make the grease composition sufficiently greasy. The content of the thickener is preferably 35% by mass or less, more preferably 30% by mass or less, and further preferably 25% by mass or less, based on the total amount of the composition. When the content of the thickener exceeds 40% by mass, the grease composition becomes excessively hard and it becomes difficult to obtain sufficient lubricating performance.

Base oil:
The base oil used in the grease composition of the present invention may be any of mineral oil, fats and oils, and synthetic oils.
As mineral oil, a mineral oil obtained by a method commonly used in a lubricating oil production process in the oil refining industry, more specifically, a lubricating oil fraction obtained by subjecting crude oil to atmospheric distillation and vacuum distillation is subjected to solvent removal. For example, paraffinic or naphthenic compounds obtained by appropriately combining one or more purification means such as rubble, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrorefining, sulfuric acid washing, clay treatment, etc. Mention may be made of mineral oil.

Examples of the fats and oils include beef tallow, lard, sunflower oil, soybean oil, rapeseed oil, rice bran oil, coconut oil, palm oil, palm kernel oil, and hydrogenated products thereof.
As biodegradable oils, various vegetable oils or synthetic oils having biodegradability collected from plant fruits and seeds such as rapeseed oil, sunflower oil and soybean oil are also disclosed in JP-A-6-1989. The polyol ester oil is preferably used. Even if it is a synthetic oil, the biodegradation rate after 21 days is usually 67% in accordance with the method defined in CEC (European Standards Advisory Committee) standard L-33-T82, which is a biodegradability evaluation method. We have a biodegradable oil that has a biodegradability of 80% or more.

  Synthetic oils include, for example, polyolefin oils, alkylbenzene oils, alkylnaphthalene oils, biphenyl oils, diphenylalkane oils, di (alkylphenyl) alkane oils, ester oils, polyglycol oils, polyphenylether oils, fluorine compounds (perfluorocarbons). Fluoropolyethers, fluorinated polyolefins, etc.), silicone oils and the like. Among these, polyolefin oils and silicone oils are preferably used from the viewpoint of friction characteristics.

  Any polyolefin oil can be used, and among these, those obtained by polymerizing one or two or more olefins having 2 to 12 carbon atoms are preferable. In addition, one obtained by polymerizing one or more of ethylene, propylene, 1-butene, 2-butene, isobutene, or a linear terminal olefin having 5 to 12 carbon atoms (hereinafter referred to as α-olefin) is more preferable. preferable.

  Among these, a copolymer of ethylene and propylene; a copolymer of ethylene and an α-olefin having 5 to 12 carbon atoms; a polymer of polybutene, polyisobutene, or an α-olefin having 5 to 12 carbon atoms is preferable, A copolymer of ethylene and an α-olefin having 5 to 12 carbon atoms and an α-olefin polymer having 5 to 12 carbon atoms are more preferable. In the present specification, the copolymer of ethylene and an α-olefin having 5 to 12 carbon atoms refers to a copolymer obtained by polymerizing one kind or two or more kinds of ethylene and an α-olefin having 5 to 12 carbon atoms. The α-olefin polymer having 5 to 12 carbon atoms refers to a homopolymer obtained by polymerizing one kind of α-olefin having 5 to 12 carbon atoms, or a copolymer obtained by polymerizing two or more kinds.

  The average molecular weight of the copolymer of ethylene and an α-olefin having 5 to 12 carbon atoms and the polymer of an α-olefin having 5 to 12 carbon atoms is preferably 500 to 4000.

  Examples of the silicone oil include dimethyl silicone oil, methylphenyl silicone oil, phenyl silicone oil, and fluorosilicone oil.

The perfluoropolyether oil can be used as long as it is a compound in which a hydrogen atom of an aliphatic hydrocarbon polyether is substituted with a fluorine atom. Examples of such perfluoropolyether oils include perfluoropolyethers having side chains represented by the following formulas I and II and linear perfluoropolyethers represented by formulas III to V: is there. These can be used alone or in combination. m and n are integers.
Fomblin Y (trade name of Montedison) as a commercial product of Formula I, Krytox (trade name of DuPont) and Barrierta J Oil (trade name of Cleaver) as commercial products of Formula II, and commercial products of Formula III Fonbrin Z (trade name of Montedison), Fonbrin M (trade name of Montedison) as a commercial product of Formula IV, and Demnam (trade name of Daikin) as a commercial product of Formula V, respectively. .

Formula I

Formula II

Formula III

Formula IV

Formula V

  The aromatic ester oil is preferably trimellitic acid ester oil represented by the following formula (II).

式中Ｒ⁴、Ｒ⁵、Ｒ⁶は炭素数が６〜１０の炭化水素基であり、Ｒ⁴、Ｒ⁵、Ｒ⁶は互いに同一であっても異なるものであってもよい。また、これらの炭化水素基は飽和又は不飽和の直鎖又は分岐アルキル基を表す。
また、一般式（ＩＩＩ）で表されるピロメリット酸エステル油も好ましい。

In the formula, R ⁴ , R ⁵ and R ⁶ are hydrocarbon groups having 6 to 10 carbon atoms, and R ⁴ , R ⁵ and R ⁶ may be the same or different from each other. Moreover, these hydrocarbon groups represent a saturated or unsaturated linear or branched alkyl group.
A pyromellitic acid ester oil represented by the general formula (III) is also preferable.

式中Ｒ⁷、Ｒ⁸、Ｒ⁹、Ｒ¹⁰は炭素数が６〜１５の炭化水素基であり、Ｒ⁷、Ｒ⁸、Ｒ⁹、Ｒ¹⁰は互いに同一であっても異なるものであってもよい。また、これらの炭化水素基は飽和又は不飽和の直鎖又は分岐アルキル基を表す。

In the formula, R ⁷ , R ⁸ , R ⁹ and R ¹⁰ are hydrocarbon groups having 6 to 15 carbon atoms, and R ⁷ , R ⁸ , R ⁹ and R ¹⁰ are the same or different from each other. Also good. Moreover, these hydrocarbon groups represent a saturated or unsaturated linear or branched alkyl group.

Polyphenyl ether oil, silicone oil, fluorine oil, etc. are known as base oils with excellent heat resistance, but polyphenyl ether oil, fluorine oil and silicone oil are very expensive, and fluorine oil and silicone oil are Generally poor lubricity. In contrast, aromatic ester oils such as trimellitic acid ester oil and pyromellitic acid ester oil have excellent heat resistance, oxidation resistance, and wear resistance. In particular, the aromatic ester oils represented by the above general formulas (II) and (III) have a low pour point and a high viscosity index. Therefore, rolling for automotive electrical equipment that requires a use environment from extremely low to high temperatures. It is preferably used for a bearing. Moreover, it is inexpensive and has good availability.
As such trimellitic acid esters, “Trimex T-08” and “N-08” manufactured by Kao Corporation, “Adeka Prover T-45”, “T-90, PT” manufactured by Asahi Denka Kogyo Co., Ltd. -50 "," UNIQEMA EMKARATE8130 "," EMKARATE9130 "," EMKARATE1320 "etc. can be obtained from the market. As pyromellitic acid esters, “Adeka Prover LX-1891”, “Adeka Prover LX-1892” manufactured by Asahi Denka Kogyo Co., Ltd., “BISOLUBETOPM” manufactured by Cognis, etc. can be obtained from the market. These have a low pour point and can be suitably used in the present invention.

  In the present invention, it is also preferable to use a base oil containing a specific diphenyl ether oil of the following formula (I) or (II). When such a base oil is used, a grease composition can be obtained that can maintain excellent lubricity for a long period of time even at a higher temperature, for example, higher than 160 ° C. Also, by encapsulating this grease composition, a rolling device with excellent lubrication performance at high temperatures and a long life can be obtained, particularly suitable for parts used at high temperatures and high speeds such as automotive electrical parts and automotive engine accessories. Can be used.

In the general formula (I), R ¹ and R ² represent the same or different linear or branched perfluoroalkyl groups or partially substituted products thereof. Here, the partially substituted product of the perfluoroalkyl group is a halogen atom such as a chlorine atom, a bromine atom, or an iodine atom, a hydroxyl group, a thiol group, an alkoxy group, an ether group, an amino group, A nitrile group, a nitrile group, a sulfonyl group, a sulfinyl group or an ester group, an amino group, an acyl group, an amide group, a group substituted with a substituent such as a carbonyl group such as a carboxyl group, or a part of the main chain is an ether structure belongs to.
Further, R ^1, the number of carbon atoms in R ² is 1 to 25, preferably 1 to 10, more preferably 1 to 3. When the number of carbon atoms exceeds 25, it becomes difficult to obtain or synthesize raw materials.
Furthermore, the ratio of the number of fluorine atoms / the number of carbon atoms in R ¹ and R ² is 0.6 to 3, preferably 1 to 3, and more preferably 1.5 to 3.
In the general formula (II), one of R ³ , R ⁴ and R ⁵ is a hydrogen atom, and the remaining two represent the same or different branched alkyl groups. Moreover, carbon number is 10-26, Preferably it is 12-24. If the number of carbon atoms is less than 10, the amount of evaporation increases, and if it exceeds 26, the fluidity at low temperatures becomes poor, which causes a problem in use. Specific examples include a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group, a nanodecyl group, an eicosyl group, and the like. .
The ratio of the diphenyl ether oil represented by the general formula (I) or the general formula (II) in the base oil is 50 to 100% by weight, preferably 60 to 80% by weight. If it is less than 50% by weight, the heat resistance becomes insufficient. As the lubricating oil that can be used in combination, ester synthetic oils and poly-α-olefin oils are preferred.

In the grease composition of the present invention, a base oil for traction grease may be used as the base oil. Preferable examples of the base oil for traction grease include hydrocarbons having a cyclic structure such as a cyclohexane ring, a decalin ring, a bicycloheptane ring and a bicyclooctane ring in the molecule (see JP 2000-109871 A).
For example, as saturated hydrocarbon compounds having a cyclohexane ring, compounds described in JP-B-3-80191, JP-B-2-52958, JP-B-6-39419, JP-B-6-92323, and the like are decalin rings. Examples of saturated hydrocarbon compounds having a bicycloheptane ring include those described in JP-B-60-43392 and JP-B-6-51874, and JP-B-5-31914 and JP-B-7. -103387 and the like, for example, 1- (1-decalyl) -2-cyclohexylpropane; 1-cyclohexyl-1-decalylethane; 1,3-dicyclohexyl-3-methylbutane; 2,4-dicyclohexylpentane 1,2-bis (methylcyclohexyl) -2-methylpropane; 1,1-bis ( Methylcyclohexyl) -2-methylpropane; 2,4-dicyclohexyl-2-methylpentane, and saturated hydrocarbon compounds having a bicyclooctane ring include known compounds described in JP-A-5-9134 Can be used. Unsaturated hydrocarbons, particularly those having a benzene ring are not preferred because they often have an adverse effect on the environment.

  The lubricating base oils described above may be used alone or in combination of two or more different lubricating base oils.

  In the grease composition of the present invention, silicone oil is preferably used from the viewpoint of friction characteristics. However, when the electrical contact or the like is in the vicinity of the lubrication part, the silicone oil may affect the electrical contact or the like. . Therefore, it is preferable to use a lubricating base oil other than silicone oil from the viewpoint of preventing the influence on electrical contacts and the like. Specifically, mineral oil, polyolefin oil, ester oil, polyglycol oil, and polyphenyl ether oil are preferable.

  In addition, if mineral oil is used as the lubricating base oil, the wettability to resin parts becomes insufficient, and friction characteristics such as lubricity and low friction properties compared to the case of using a lubricating base oil that does not contain mineral oil. May become insufficient. Therefore, it is preferable to use a lubricating base oil other than mineral oil from the viewpoint of friction characteristics such as lubricity and low friction. Specifically, polyolefin oil, silicone oil, ester oil, polyglycol oil, and polyphenyl ether oil are preferable.

  Further, when ester oil is used as the lubricating base oil, it may adversely affect the resin member or rubber member. Therefore, it is preferable to use a lubricating base oil other than ester oil in terms of preventing adverse effects on the resin member and rubber member. Specifically, mineral oil, polyolefin oil, silicone oil, polyglycol oil, and polyphenyl ether oil are preferable.

  Therefore, polyolefin is preferable for achieving a high level of balance between friction characteristics, prevention of influences on electrical contacts, and prevention of adverse effects on resin and rubber members. Among them, ethylene and propylene are preferred. A copolymer of ethylene and an α-olefin having 5 to 12 carbon atoms; a polymer of polybutene, polyisobutene, or an α-olefin having 5 to 12 carbon atoms is more preferable; More preferred are a copolymer of 12 α-olefins and a polymer of α-olefins having 5 to 12 carbon atoms.

Kinematic viscosity at 100 ° C. of the base oil for grease composition maintains a suitable viscosity, is preferably 1~2000mm ² / s, more preferably 3~1000mm ² / s, 5~ More preferably, it is 500 mm < ² > / s.

  The content of the base oil is preferably 50% by mass or more, more preferably 60% by mass or more, based on the entire composition. When the content of the base oil is less than 50% by mass, it tends to be difficult to obtain good lubricity. The content of the base oil is preferably 95% by mass or less, more preferably 90% by mass or less, based on the entire composition. When the content of the base oil exceeds 95% by mass, it tends to be difficult to make the grease composition sufficiently greasy.

Consistency:
The grease composition of the present invention has a miscibility of 480 or less at 40 ° C., preferably 205 to 395, more preferably 220 to 395, still more preferably 265 to 350, and even more preferably automatic lubrication. Therefore, it is 280-320. If the penetration is less than 205, the grease may be too hard. If it exceeds 480, the grease may be too soft and grease leakage may occur.
The penetration is defined in item 5.3 of JIS K 220-1993, and the specified cone is inserted into the document container placed in a flat container by its own weight for 5 seconds. Double is defined as consistency. The blending consistency is measured immediately after mixing the material in the mixer at 25 ° C and then mixing the material for 60 strokes. It is used for the NLGI consistency classification. It depends on.

Other additives:
As long as the grease composition of the present invention does not impair its properties, the solid lubricant, wax, extreme pressure agent, antioxidant, oiliness agent, rust inhibitor, viscosity index improver, A conductive substance or the like can be contained.

  Examples of solid lubricants include polytetrafluoroethylene, boron nitride, fullerene, graphite, fluorinated graphite, melamine cyanurate, molybdenum disulfide, Mo-dithiocarbamate, antimony sulfide, and alkali (earth) metal borates. Can be mentioned.

  Examples of the wax include natural waxes, mineral oils and various synthetic waxes, and specifically include montan wax, carnauba wax, amide compounds of higher fatty acids, paraffin wax, microcrystalline wax, polyethylene wax, polyolefin wax. And ester wax.

  By blending an extreme pressure agent, load resistance and extreme pressure properties can be improved. For example, the following compounds can be used. As organometallic compounds, organic molybdenum compounds such as molybdenum dithiocarbamate and molybdenum dithiophosphate, organic zinc compounds such as zinc dithiocarbamate, zinc dithiophosphate and zinc phenate, organic antimony compounds such as antimony dithiocarbamate and antimony dithiophosphate, Organic selenium compounds such as selenium dithiocarbamate, organic bismuth compounds such as bismuth naphthenate and bismuth dithiocarbamate, organic iron compounds such as iron dithiocarbamate and iron octylate, organic copper compounds such as copper dithiocarbamate and copper naphthenate, naphthenic acid Organic lead compounds such as lead and lead dithiocarbamate, organic tin compounds such as tin maleate and dibutyltin sulfide, or organic sulfonates, phenates and phosphates of alkali metals and alkaline earth metals Sulfonates, gold, silver, an organic metal compound such as titanium can be used if necessary. As the sulfur compounds, sulfides such as dibenzyl disulfide or polysulfide compounds, sulfurized fats and oils, ashless carbamic acid compounds, thiourea compounds, thiocarbonates, and the like can be used. As the phosphoric acid extreme pressure agent, it is possible to use phosphate compounds such as trioctyl phosphate, tricresyl phosphate, etc., phosphate esters, acidic phosphate esters, phosphite esters, acidic phosphite esters, etc. it can. In addition, halogen-based extreme pressure agents such as chlorinated paraffin, or solid lubricants such as boron compounds such as molybdenum disulfide, tungsten disulfide, graphite, polytetrafluoroethylene, antimony sulfide, and boron nitride are used. can do. Among these extreme pressure agents, dithiocarbamic acid compounds and dithiophosphoric acid compounds can be suitably used.

  As the antioxidant, an antioxidant, an ozone deterioration inhibitor, and an antioxidant that are added to rubber, plastic, lubricating oil, and the like can be appropriately selected and used. For example, the following compounds can be used. That is, phenyl-1-naphthylamine, phenyl-2-naphthylamine, diphenyl-p-phenylenediamine, dipyridylamine, phenothiazine, N-methylphenothiazine, N-ethylphenothiazine, 3,7-dioctylphenothiazine, p, p'-dioctyldiphenylamine An amine compound such as N, N′-diisopropyl-p-phenylenediamine, N, N′-di-sec-butyl-p-phenylenediamine, or the like can be used. A phenolic antioxidant can also be used. Examples of the phenolic antioxidant include 2,6-di-t-dibutylphenol, n-octadecyl-3- (3 ′, 5′-di-tert-butyl-4-hydroxyphenyl) propionate, tetrakis- ( Methylene-3- (3 ′, 5′-di-t-butyl-4-hydroxyphenyl) propionate) methane, 2,2′-methylenebis- (4-methyl-6-tert-butylphenol), 4,4′- Butylidenebis- (3-methyl-6-tert-butylphenol) and the like.

  Examples of the oily agent include amines such as laurylamine, myristylamine, palmitylamine, stearylamine and oleylamine; higher alcohols such as lauryl alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol and oleyl alcohol; lauric acid, Higher fatty acids such as myristic acid, palmitic acid, stearic acid, oleic acid; fatty acid esters such as methyl laurate, methyl myristate, methyl palmitate, methyl stearate, methyl oleate; laurylamide, myristylamide, palmityl Amides such as amide, stearylamide and oleylamide;

Examples of rust inhibitors include nitrites and metal soaps as water-soluble inorganic passivating agents; polyhydric alcohol partial esters such as organic sulfonates and sorbitan fatty acid esters; amines; phosphoric acid; Is mentioned.
Passivating oxidizer is an oxidizer that causes passivation of metal surfaces such as steel constituting rolling bearings. For example, nitrite, nitrate, chromate, phosphate, molybdate, tungsten Cathode depolarization type inorganic corrosion inhibitor such as acid salt is used.
Carboxylic acid-based rust preventives include linear fatty acids such as lauric acid and stearic acid, saturated carboxylic acids having a naphthene nucleus, succinic acid, alkyl succinic acid, alkyl succinic acid half ester, alkenyl succinic acid, alkenyl succinic acid half ester And succinic acid derivatives such as succinimide, hydroxy fatty acids, mercapto fatty acids, sarcosine derivatives, and oxidized waxes such as waxes and petrolatum oxides. Examples of the carboxylate-based rust preventive include metal salts such as fatty acids, naphthenic acids, apietic acids, lanolin fatty acids, alkenyl succinic acids, hydroxy fatty acids, amino acid derivatives, and the like. Examples of the metal element include cobalt, manganese, zinc, aluminum, calcium, barium, lithium, magnesium, copper, and the like.
Such metal soaps are preferable for maintaining water resistance because they can maintain the lubricating oil and maintain the mixing effect while maintaining a certain amount of mixed water.
A grease composition to which a polyhydric alcohol ester is added is known. Examples of the polyhydric alcohol include aliphatic polyhydric alcohols such as glycerin, polyglycerin, sorbitol, sorbitan, pentaerythritol, and trimethylolpropane. The fatty acid that forms an ester with the polyhydric alcohol is a compound represented by RCOOH. R represents a saturated or unsaturated hydrocarbon group. The fatty acid is preferably a higher fatty acid, such as lauric acid, myristic acid, palmitic acid, beef tallow acid, stearic acid, caproleic acid, undecylenic acid, Linderic acid, tuzuic acid, fizeteric acid, myristoleic acid, palmitoleic acid, petrothelic acid, Examples include oleic acid, elaidic acid, asclepic acid, vaccenic acid, sorbic acid, linoleic acid, linolenic acid, sabinic acid, ricinoleic acid, and behenic acid.
Among these polyhydric alcohols in which a part of the hydroxyl groups are blocked, sorbitan fatty acid esters are preferable, and sorbitan trioleate is particularly preferable. By using in combination with poly-α-olefin oil or the like, the rust prevention performance can be further improved.
Organic sulfonates, fatty acid esters or a mixture of both are also known as rust inhibitors. The organic sulfonate salt is a salt of sulfonic acid (RSO ₃ H) and is generally represented as RSO3M. Examples of the sulfonic acid include petroleum sulfonic acid and dinonylnaphthalene sulfonic acid. Examples of M include metals such as barium, calcium, zinc, sodium, lithium, and magnesium, and amines such as NH ₄ and H ₂ N (CH ₂ ) ₂ NH ₂ . Among the above, calcium salt or sodium salt of sulfonic acid is preferable. Fatty acid esters include succinic acid, stearic acid, oleic acid and the like as the acid component, and isopropyl alcohol, 2-ethylhexyl alcohol, n-octyl alcohol, oleyl alcohol and the like as the alcohol component. Of these, succinic acid esters are preferred.
In addition, organic sulfonates are known to improve heat resistance and load resistance. Overbased calcium sulfonate has excellent lubrication performance at low temperatures, and is effective in improving the durability life effect, suppressing fretting and suppressing abnormal noise during cold.
In addition, benzotriazole, benzimidazole, thiadiazole and the like are known as metal deactivators.

Examples of the thickener include polymethacrylate, polyisobutylene, polystyrene and the like.
Poly (meth) acrylate is also known to prevent cold abnormal noise in cold regions.

In general, a rolling bearing with a lubricant is used for a rotary bearing portion of a food machine or the like. However, these mineral oil-based grease compositions may be scattered during machine operation and come into contact with food, which is not preferable for food hygiene. In addition, there is a possibility that bacteria may be mixed in the grease, and the possibility of affecting the food is considered sufficiently. As a grease composition for solving such a problem, a grease composition containing an antibacterial zeolite as an antibacterial agent is known. Moreover, a natural antibacterial agent is preferable for safety. Specific examples thereof include chitosans, catechins, Somune bamboo, mustard, and wasabi essential oil. In addition, it is a basic protein contained in mature testis such as colloidal pectin, which is abundant in apples, grapes, and citrus fruits, and polylysine, salmon, trout, herring, etc., in which the essential amino acid L-lysine is connected in a straight chain. Extract from protamine, Dutch seed extract, spices from dried leaves of Lamiaceae plants such as rosemary, sage, and thyme, hydrophobic organic solvent extract of pearl barley, Iriomote thistle rhizome extract, and honeycomb Many antibacterial substances such as propolis can be used.
Among them, catechins that are highly effective for various food poisoning are preferable. Among them, epigallocatechin, epicatechin, epicatechin gallate, epigallocatechin gallate, catechin and the like, which are water-soluble components contained in tea leaves, are preferable. In general, since these catechins are water-soluble, it is preferable to add a small amount of a surfactant, but in the case of a grease composition, the thickener also serves as a surfactant. There is no need to add a surfactant.

  Further, the grease composition of the present invention has high compatibility with rubber disposed in the vicinity of the sliding portion. The rubber is not particularly limited, and specific examples include nitrile, chloroprene, fluorine, ethylene-propylene, acrylic, and composites thereof.

It is known that static electricity generated in a rolling bearing has an adverse effect such as distortion on a copy image of a copying machine, but coexistence of a conductive substance is effective in suppressing the static electricity. The conductive substance is added in an amount of 2 to 10% by mass based on the total amount of grease. Among the conductive materials, carbon black and graphite are preferable, and each can be used alone or in combination. When mixed and used, the total amount is the amount added as described above. Carbon black and graphite preferably have an average particle size of 10 to 300 nm.
In addition, it is known that the conductive substance is also effective as an anti-release agent described in the extreme pressure agent section. This conductive substance has an effect of suppressing white peeling caused by hydrogen ions, as described in JP-A-2002-195277.

  It is also known to add a hollow filler or silica particles in order to increase the heat insulation of the grease, or to add metal powder such as copper in order to promote heat transfer or heat dissipation.

  Lubricating grease compositions with excellent flame retardancy include powders such as alkali metal or alkaline earth metal oxides and carbonates added to lithium soap greases, and calcium carbonate and platinum compounds added to silicone greases. A product in which a water-absorbing polymer and water are contained in a grease is known.

[Machine elements]
The present invention relates to a machine element comprising at least two surfaces capable of moving at different peripheral speeds and the grease composition of the present invention disposed between the two surfaces. In this specification, “mechanical element” means a tribo mechanical element, that is, a sliding element, a rolling element, a conductive element, or a sealing element of a sliding machine part. Most machines have a tribo element because they are “moving” in a word. By moving, inertial force is first applied to cause destruction, vibration and noise problems, and tribologic problems such as friction, wear and leakage occur in the tribo element. This destruction, vibration / noise, and tribology trouble are the three major troubles of the machine. Therefore, the present invention is an effective technique for preventing these troubles beforehand, and the mechanical elements of this specification are related to the technique. It is a tribo element.
The circumferential speed of the two surfaces is not particularly limited. For example, in the case of a sintered oil-impregnated bearing, the circumferential speed is about 0.01 to 10 m / sec, and the difference between the circumferential speeds of the two surfaces is the same. In the case of a thrust bearing, the circumferential speed is about 10 to 120 m / sec, and the difference between the circumferential speeds of the two surfaces is the same.

  Specifically, it is used for the purpose of lubrication and protection of contact parts between sliding parts such as rolling bearings, slide bearings, sintered bearings, gears, bubbles, cocks, oil seals, electrical contacts, and the like. For example, bearings that require heat resistance, low temperature, load resistance, etc. for automobile hub units, traction motors, fuel injection devices, alternators, etc., wear resistance for automobile power transmission devices, power window motors, wipers, etc. Bearings that require low torque and low outgas properties, such as gears that require low friction characteristics and high torque efficiency, hard disks used in information equipment, flexible disk storage devices, compact disk drives, magneto-optical disk drives, etc. For sliding parts such as bearings and gears used in pumps, resin manufacturing equipment, conveyors, wood industry equipment, chrome coating equipment, etc., electrical contact parts of electrical equipment used in breakers, circuit breakers, relays, switches, etc. Effectively protects the metal surfaces used.

There are no particular restrictions on the material of the two moving surfaces, and the grease composition of the present invention has low friction with respect to any of steel, various metals other than steel, inorganic or organic materials other than metals, and mixtures thereof. Excellent in wear resistance and wear resistance.
Examples of steel include carbon steel for mechanical structures, alloy steel for structural machinery such as nickel chrome steel, nickel chrome molybdenum steel, chrome steel, chrome molybdenum steel, aluminum chrome molybdenum steel, stainless steel, multi-aging steel, etc. .
Various metals other than steel, or inorganic or organic materials other than metals are also widely used.
Examples of inorganic or organic materials other than metals include various plastics, ceramics, carbon, etc., and mixtures thereof. More specifically, examples of the metal material other than steel include cast iron, copper / copper-lead / aluminum alloy, castings thereof, and white metal.
Organic materials include all general purpose plastics and engineering plastics such as high density polyethylene (HDPE), polyamide, polyacetal (POM), polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polybutylene naphthalate, polyphenylene ether, polyphenylene sulfide (PPS). , Fluororesin, tetrafluoroethylene resin (PFPE), polyarylate, polyamideimide (PAI), polyetherimide, polypyromellitimide, polyetheretherketone (PEEK), polysulfone, polyethersulfone, polyimide (PI) , Polystyrene, polyethylene, polypropylene, phenol resin, AS resin, ABS resin, AES resin, AAS resin, ACS resin, MBS Fat, polyvinyl chloride resins, epoxy resins, diallyl phthalate resins, polyester resins, methacrylic resins, are applied to the ABS / polycarbonate alloy, or the like.
These resins form a molded product or a resin layer as various parts or members, and this grease composition is applied to a place where these resins come into contact with other resins or metals. Specifically, for example, sliding parts of automobile electrical components represented by electric power steering, door mirrors, etc., resin gears of acoustic equipment such as bearings, resin gears, radio cassettes, VTRs, CD players, and laser beam printers. Effectively applied to contact points between resin materials and other resin materials or metal materials that form resin gear parts of OA equipment such as printers, copiers and fax machines, various actuators for automobiles, sliding parts inside air cylinders, etc. Is done.

Examples of the inorganic material include ceramics such as silicon carbide, silicon nitride, alumina, zirconia, titanium carbide (TiC), zirconia carbide (ZrC), and titanium nitride (TiN); and carbon materials. Examples of these mixtures include organic-inorganic composite materials in which fibers such as glass, carbon, or aramid are combined in plastic, and ceramic and metal composite material cermets.
When a part is made of a material other than steel, at least a part of the surface of the steel material may be coated with a metal material other than steel, or a film made of an organic or inorganic material other than the metal material. Examples of the coating film include a magnetic material thin film such as a diamond-like carbon thin film, and an organic or inorganic porous film.

Also, a porous sintered layer is formed on at least one of the two surfaces, and the porous layer is impregnated with a lubricant composition, and the lubricant composition is appropriately supplied to the sliding surface during sliding. You may comprise. The porous layer may be made of any of a metal material, an organic material, and an inorganic material. Specifically, sintered ceramics, porous ceramics formed by strongly bonding fine particles of calcium zirconate (CaZrO ₃ ) and magnesia (MgO), silica and boric acid components are thermally separated. Porous glass, ultra-high molecular weight polyethylene powder sintered porous molding, fluororesin-based porous membrane such as ethylene tetrafluoride, polysulfone-based porous membrane used for microfilters, etc. Examples thereof include a porous film formed by causing phase separation during polymerization of a poor solvent and its molded body forming monomer.

Examples of the metal or metal oxide sintered layer include a porous layer formed by sintering a copper-based, iron-based, or TiO ₂ -based powder. The copper-based metal sintered layer is formed by compressing and forming a mixture of copper powder (for example, 88% by mass), tin (for example, 10% by mass) and graphite (for example, 2% by mass) on a cast iron substrate at 250 MPa. Can be formed by sintering in a reducing stream at a high temperature, for example, about 770 ° C. for about one hour. In addition, the iron-based metal sintered layer is compression-molded at 250 MPa by placing a mixture of iron powder with copper powder (eg, 3% by mass) and chemical carbon (0.6% by mass) on a cast iron substrate. Can be formed by sintering in a reducing gas stream at a high temperature, for example, about 770 ° C. for about one hour. The TiO ₂ sintered layer is made of a mixture of Ti (OC ₈ H ₁₇ -n) (for example, 33% by mass), fine powder of TiO ₂ (for example, 57% by mass) and PEO (molecular weight MW = 3000), It is formed by installing on cast iron and heating and sintering at 560 ° C. for 3 hours while irradiating with UV light.
The material covered with these porous layers is not particularly limited, and may be the above-described ceramic, resin, organic-inorganic composite material, or, of course, steel.

A film such as a magnetic material thin film such as the diamond-like carbon thin film can be formed by surface treatment. Details of the surface treatment are described in Tribology Handbook, 1st Edition (2001), Chapter B, Surface Modification, pages 544-574, edited by the Japanese Society of Tribology, and are used for the production of the machine element of the present invention. be able to. Surface treatment is generally aimed at improving tribological properties by surface modification, but not only low friction and wear resistance are driven for machine elements, but also according to the demands of the driving environment. Various material properties such as low noise, corrosion resistance, chemical stability, heat resistance, dimensional stability, low outgas, biocompatibility, and antibacterial properties are often required. Accordingly, in the present invention, surface treatment improves tribological properties. It is not limited to what is made for the purpose. As a surface treatment method,
1) Aluminum, copper, silver, gold, chromium, molybdenum, tantalum or their alloy films, titanium nitride, chromium nitride, titanium carbide, carbonized by vacuum vapor deposition, ion plating, sputtering, physical vapor deposition (Physical Vapor Deposition) method Formation of oxide films such as ceramics such as chromium, aluminum oxide, silicon dioxide, molybdenum silicide, tantalum oxide, barium titanate;
2) Various metals using a chemical vapor deposition method using heat, plasma, light, etc., carbides such as WC, TiC and B ₄ C, nitrides such as TiN and Si ₃ N ₄ , TiB ₂ and W ₂ B ₃ Formation of borides such as Al ₂ O ₃ and ZrO ₂ , amorphous carbon films containing CrW, Ti metal, fluorine-containing carbon films, plasma polymerized films;
3) A method for imparting characteristics such as wear resistance and seizure resistance of the surface layer by diffusion coating methods (chemical reaction methods) such as carburizing, nitriding, sulfurating, and boriding; and 4) electroplating, electroless Examples thereof include metals by plating methods such as plating, and composite metal films.

  The present invention will be described more specifically with reference to the following examples. The materials, reagents, ratios, operations, and the like shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the following examples.

[Example 1: Performance evaluation of grease composition]
Exemplified compounds DGTR-5, DGTS-1, DGSCP-1, DGCX-3, DGSP-1, and lubricant base oils, respectively, and greases having the compositions shown in Tables 1 to 3 below (Examples 1 to 9 and Comparative Examples) 1-4) were prepared respectively.
A friction test was performed to measure the friction coefficient and the wear scar depth. In addition, the friction coefficient in an Example was measured using the reciprocating type friction tester (SRV friction wear tester), and the friction test was done on the following test conditions. The results of Examples 1 to 5 are shown in Table 1, and similarly, the results of Comparative Examples 1 to 4 are shown in Table 2.
(Test conditions)
The test conditions were ball-on-plate conditions.
Test piece (friction material): SUJ-2
Plate: φ24 × 6.9mm
Ball: φ10mm
Temperature: 120 ° C
Load: 300N
Amplitude: 1.0 mm
Frequency: 50Hz
Test time: Measured 30 minutes after the start of the test.

  ADVANTAGE OF THE INVENTION According to this invention, the grease composition which can be used as lubrication grease used for various internal combustion engines and machine tools, such as a machine tool, a sliding part of components, etc. can be provided.

Claims (31)

A grease composition containing at least one discotic compound having a discotic mother nucleus, at least one thickener, and a base oil and having a blending degree at 40 ° C. of 480 or less. The grease composition according to claim 1, wherein at least one of the discotic compounds is a compound represented by the following general formula (1):

In the formula, D represents a cyclic group that can be bonded to m side chains, X is each independently a single bond, NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms). Represents a divalent linking group comprising an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or a combination thereof, and each R is independently a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aryl group, Represents a heterocyclic group, a halogen atom, a hydroxy group, an amino group, a mercapto group, a cyano group, a sulfide group, a carboxy group or a salt thereof, a sulfo group or a salt thereof, a hydroxyamino group, a ureido group, or a urethane group; Represents an integer of 11. The grease composition according to claim 2, wherein D is a group having a 5- to 7-membered ring structure, or a residue of a porphyrin ring or a phthalocyanine ring. The grease composition according to claim 2, wherein D is a tautomer group represented by the following general formula (2) or (3):

In formula (2), A is a ring composed of 5 to 7 atoms, and one or two or more of the ring constituent atoms may have a substituent or may be condensed with another ring. May be;

In formula (3), B is a ring composed of 5 to 7 atoms, and one or two or more of the ring constituent atoms may have a substituent or may be condensed with another ring. It may be. The grease composition according to claim 2, wherein D is a group represented by the following general formula (4):

In the formula (4), each Z independently represents any of an oxygen atom, a sulfur atom, and —NR—, and may be the same or different from each other; R is a hydrogen atom or a substituent Represents an optionally substituted alkyl group. The grease composition according to claim 2, wherein the discotic compound is a compound represented by the following general formula (5):
General formula (5)

In the formula, X ¹ , X ² and X ³ are each independently a single bond, an NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms), an oxygen atom, a sulfur atom, a carbonyl group, R ¹¹ , R ¹² and R ¹³ each independently represents a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aryl group, halogen atom, hydroxy group, or a divalent linking group comprising a sulfonyl group or a combination thereof. Represents a group, amino group, mercapto group, cyano group, sulfide group, carboxy group or salt thereof, sulfo group or salt thereof, hydroxyamino group, ureido group or urethane group. The grease composition according to claim 2, wherein the discotic compound is a compound represented by the following general formula (6):
General formula (6)

In the formula, X ²¹ , X ²² and X ²³ are each independently a single bond, NR ¹ group (R ¹ is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms), oxygen atom, sulfur atom, carbonyl group Represents a divalent linking group comprising a sulfonyl group or a combination thereof, and R ²¹ , R ²² and R ²³ each independently represents a substituent. a21, a22 and a23 each independently represents an integer of 1 to 5; The disk-shaped compound has at least one kind of substituent bonded to the disk-shaped mother nucleus, and at least one kind of the substituent is a tautomeric group or partially contains a tautomeric group. The grease composition according to any one of -7. The tautomeric group is a tautomeric group represented by the following general formula (7) or (8), or a tautomerizable ureylene group, urethane group, amide group or ureido group. Grease composition:

In Formula (7), A is a ring composed of 5 to 7 atoms, and one or two or more of the ring constituent atoms may have a substituent or may be condensed with another ring. May be;

In formula (8), B is a ring composed of 5 to 7 atoms, and one or two or more of the ring constituent atoms may have a substituent or may be condensed with another ring. It may be. The grease composition according to claim 8, wherein the tautomeric group is a tautomeric ureylene group. The said discotic compound has at least 1 type of substituent couple | bonded with the discotic mother nucleus, This substituent contains the organopolysiloxane group represented by following General formula (9). The grease composition according to item:

In formula (9), R independently represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 18 carbon atoms, which may be the same or different from each other; R ¹ independently Represents an alkyl group having 1 to 6 carbon atoms, which may be the same or different; x represents an integer of 5 to 120, and y represents 0 or 1. The disk-shaped compound has at least one kind of substituent bonded to the disk-shaped mother nucleus, and the substituent includes a polyfluorinated alkyl group or a polyfluorinated alkyl ether group represented by the following general formula (10). Item 12. The grease composition according to any one of Items 1 to 11:

In formula (10), Rf represents a C1-C15 perfluoroalkyl group, m, n, p, and q are 0 or an integer greater than or equal to 1, m + n + p + q is 2-200; r is 0 or When r is 0, s is 1, Rf is a perfluoroalkyl group having 12 or more carbon atoms, and when r is 1, s represents 0 or 1. The grease composition according to any one of claims 1 to 12, wherein the discotic compound has at least one substituent containing an ester bond as a substituent bonded to the discotic mother nucleus. The discotic compound according to any one of claims 1 to 13, wherein the discotic compound has at least one substituent containing a divalent group represented by the following general formula (11) as a substituent bonded to the discotic mother nucleus. The grease composition described:

In formula (11), n represents an integer of 2 or more. The grease composition according to claim 1, comprising at least one silicone oil as the base oil. The grease composition according to any one of claims 1 to 15, comprising at least one polyfluorinated alkyl ether oil as the base oil. The grease composition according to any one of claims 1 to 16, which contains at least one diphenyl ether oil represented by the following general formula (12) or general formula (13) as the base oil:

In the formula (12), R ² and R ³ each independently represents a linear or branched perfluoroalkyl group or a partially substituted product thereof, the number of carbon atoms is 1 to 25, and R ² , R The ratio of the number of fluorine atoms / number of carbon atoms of ³ is 0.6-3;

In the formula (13), one of R ⁴ , R ⁵ and R ⁶ is a hydrogen atom, the other each independently represents a linear or branched alkyl group, and the number of carbon atoms is 1 to 26. . The grease composition according to any one of claims 1 to 17, which contains at least one aromatic ester oil having at least three side chains having a carboester group as the base oil. The grease composition according to claim 1, comprising at least one biodegradable oil as the base oil. The grease composition according to any one of claims 1 to 19, wherein the base oil contains at least one aromatic ester oil having 6 to 15 carbon atoms in a hydrocarbon group. 3-6, wherein the base oil is composed of at least (A) α-alkylstyrene 2-trimer hydride or (B) cyclopentadiene and at least one of α-olefins and monovinyl aromatic hydrocarbons. The ratio (ND / CD) of the amount of hydrogen (ND) on the double bond of the norbornene ring and the amount of hydrogen (CD) on the double bond of the cyclopentadiene ring is 0.9 to 1. 3 or (C) a saturated hydrocarbon-based synthetic hydrocarbon having a cyclic structure of any one of a cyclohexane ring, a decalin ring, a bicycloheptane ring and a bicyclooctane ring in the molecule. The grease composition according to claim 1, which is one kind selected. The grease composition according to any one of claims 1 to 21, comprising at least one organic thickener as the thickener. The grease composition according to any one of claims 1 to 22, wherein the thickener contains at least one metal soap thickener. The grease composition according to any one of claims 1 to 23, which contains at least one urea-based thickener as the thickener. The grease composition according to any one of claims 1 to 24, which contains at least one inorganic thickener as the thickener. The grease composition according to any one of claims 1 to 25, which has a penetration degree at 40 ° C of 205 to 395. The grease composition according to any one of claims 1 to 26, wherein the discotic compound is contained in an amount of 0.5 to 40% by mass. The grease composition according to any one of claims 1 to 27, which contains 5 to 40% by mass of the thickener. 29. A machine element comprising at least two surfaces movable at different peripheral speeds and the grease composition according to any one of claims 1 to 28 disposed between the two surfaces. The machine element according to claim 29, wherein at least one of the two surfaces is made of a resin. 30. A machine element according to claim 29, wherein at least one of the two faces is diamond-like carbon or ceramic.