WO2017126487A1

WO2017126487A1 - Lubricant composition and method for producing lubricant composition

Info

Publication number: WO2017126487A1
Application number: PCT/JP2017/001330
Authority: WO
Inventors: 児玉　邦彦; 藤原　淑記
Original assignee: 富士フイルム株式会社
Priority date: 2016-01-19
Filing date: 2017-01-17
Publication date: 2017-07-27
Also published as: JP6527248B2; JPWO2017126487A1

Abstract

The present invention addresses the problem of providing a lubricant composition capable of achieving a reduction in friction at various temperatures and loads. The present invention pertains to a lubricant composition which contains an ester compound having 20 or more carbon atoms and containing at least one ester bond and at least one carboxyl group per molecule, and a method for producing the lubricant composition. The lubricant composition according to the present invention preferably contains an esterification reaction mixture of a divalent or polyvalent carboxylic acid and a mono-ol. In the esterification reaction mixture, 40-95% of all carboxyl groups in all the divalent or polyvalent carboxylic acid molecules are preferably esterified by the mono-ol.

Description

Lubricant composition and method for producing lubricant composition

The present invention relates to a lubricant composition. More specifically, the present invention relates to a lubricant composition containing a specific ester compound, which can exhibit a low friction property.

Lubricant composition generally includes base oil and various additives. Base oils include mineral oils obtained from crude oils, chemically synthesized ester oils, fluorine oils, polyalphaolefin oils, and the like. Among these, ester oils are suitably used for jet aircraft, automobile engine oils, greases and the like because of their low pour point, high viscosity index, high flash point, good lubricating properties, biodegradability, and the like.

It is known that ester oils are used as base oils or additives. For example, a monoester having less than 20 carbon atoms obtained from the reaction between an aliphatic monocarboxylic acid and a monohydric alcohol; a diester obtained from the reaction between an aliphatic dibasic acid and a monohydric alcohol; a polyhydric alcohol and an aliphatic carboxylic acid Various esters are disclosed (Patent Documents 1 to 9), such as a polyol ester obtained from a reaction with a polyol, a complex ester obtained from a reaction with a polyol, a polybasic acid, and an aliphatic monocarboxylic acid.

JP 2002-097482 A JP 2005-154726 A JP 2005-232434 A JP 2005-213377 A JP 2005-232470 A Special table 2001-501989 JP-T-2001-500549 JP-T-2001-507334 Japanese translation of PCT publication No. 2002-530476

In recent years, with the diversification and sophistication of the industrial field, lubricant compositions are required to have high lubrication performance. Further, the lubricant composition is required to exhibit good friction characteristics at various temperatures and load regions.

The problem to be solved by the present invention is to provide a lubricant composition that can achieve low friction at various temperatures and loads.

As a result of various studies to solve the above-mentioned problems, the present inventor has included a compound having an ester compound having a specific structure and carbon number, thereby providing lubrication that can exhibit good friction characteristics at various temperatures and load regions. It was found that an agent composition was obtained.
That is, the said subject is solved by this invention of the following structures.

[1] A lubricant composition containing an ester compound having 20 or more carbon atoms and containing at least one ester bond and a carboxyl group in one molecule.
[2] The lubricant composition according to [1], wherein the number of ester bonds contained in one molecule of the ester compound having 20 or more carbon atoms is 1 to 3.
[3] The lubricant composition according to [1] or [2], wherein the number of carboxyl groups contained in one molecule of the ester compound having 20 or more carbon atoms is 1 to 3.
[4] The number of ester bonds contained in one molecule of an ester compound having 20 or more carbon atoms is 1, and the number of carboxyl groups contained in one molecule of an ester compound having 20 or more carbon atoms is [1. ]-[3] The lubricant composition according to any one of [3].
[5] The lubricant composition according to any one of [1] to [4], wherein the ester compound having 20 or more carbon atoms has an oxyalkylene structure.
[6] The lubricant composition according to [1], wherein the ester compound having 20 or more carbon atoms is represented by the following general formula Ax;

In the general formula Ax, Y represents an m + n-valent linking group, Y a carbon number + m + n is not less than 10, m is an integer of 1 or more, n is an integer of 1 or more, R ^b is a monovalent Represents a substituent.
[7] The lubricant composition according to [6], wherein Y in General Formula Ax has 8 or more carbon atoms.
[8] Y in general formula Ax is a residue of a succinic acid having a substituent having 8 or more carbon atoms or a residue of a multimer of unsaturated fatty acids having 16 or more carbon atoms, according to [6] or [7] Lubricant composition.
[9] The lubricant composition according to any one of [6] to [8], wherein the carbon number of Y in the general formula Ax is 34 or more.
[10] The lubricant composition according to any one of [6] to [9], wherein R ^b in the general formula Ax has 8 or more carbon atoms.
[11] The lubricant composition according to [1], wherein the ester compound having 20 or more carbon atoms is represented by the following general formula Ay;

In general formula Ay, Y represents an m + n-valent linking group, Y carbon number + m + n is 10 or more, L is an alkylene group, m is an integer of 1 or more, and n is an integer of 1 or more. , P is an integer of 1 or more, and R ^c represents a monovalent substituent.
[12] The lubricant composition according to any one of [1] to [11], further comprising a complete ester compound of a polyvalent carboxylic acid and having 20 or more carbon atoms.
[13] The lubricant composition according to any one of [1] to [12], further comprising a compound containing as a constituent element at least one selected from zinc, molybdenum, sulfur and phosphorus.
[14] A method for producing a lubricant composition comprising a step of esterifying a part of a carboxyl group of a polyvalent carboxylic acid with a monool, wherein at least one ester bond and a carboxyl group are contained in one molecule. A method for producing a lubricant composition comprising an ester compound having 20 or more carbon atoms.
[15] The step of esterifying is a step of esterifying 40 to 95% of all carboxyl groups in all molecules of the polyvalent carboxylic acid with monool. Production method.

The lubricant composition of the present invention can exhibit good friction characteristics at various temperatures and load regions.

Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be made based on representative embodiments and specific examples, but the present invention is not limited to such embodiments. In the present specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

(Lubricant composition)
The lubricant composition of the present invention contains an ester compound having 20 or more carbon atoms containing at least one ester bond and one carboxyl group in one molecule. One molecule of the ester compound having 20 or more carbon atoms contained in the lubricant composition of the present invention may contain at least one ester bond, but the number of ester bonds contained in one molecule of the ester compound is 1 to 3, preferably 1 or 2, and more preferably 1. In addition, one molecule of the ester compound having 20 or more carbon atoms contained in the lubricant composition of the present invention may contain at least one carboxyl group, but the number of carboxyl groups contained in one molecule of the ester compound is It is preferably 1 to 3, more preferably 1 or 2, and still more preferably 1. Among them, it is more preferable that one molecule of the ester compound having 20 or more carbon atoms contained in the lubricant composition of the present invention has a structure including one ester bond and one carboxyl group. The ester compound contained in the lubricant composition of the present invention has 20 or more carbon atoms, preferably 24 or more, more preferably 28 or more, and further preferably 36 or more.

Since the lubricant composition of the present invention is configured as described above, it can exhibit good friction characteristics at various temperatures and loads. For this reason, the lubricant composition of the present invention is preferably used even under severe conditions such as high temperature and / or high pressure.

(Ester compound)
The ester compound having 20 or more carbon atoms as described above preferably has an oxyalkylene structure. An oxyalkylene structure refers to a structure in which an oxygen atom is introduced into an alkylene chain. The alkylene chain in the oxyalkylene structure may be linear, branched or cyclic. The oxyalkylene structure preferably contains an oxyethylene group or an oxypropylene group, and more preferably contains an oxyethylene group. Further, the ester compound may contain a polyoxyalkylene structure containing two or more oxyalkylene groups. The polyoxyalkylene structure preferably contains a polyoxyethylene group or a polyoxypropylene group, and more preferably contains a polyoxyethylene group.

The ester compound having 20 or more carbon atoms is preferably a compound represented by the following general formula Ax.

Here, in general formula Ax, Y represents an m + n-valent linking group, Y carbon number + m + n is 10 or more, m is an integer of 1 or more, n is an integer of 1 or more, and R ^b is Represents a monovalent substituent. Y, m, n and Rb in the general formula Ax are selected so that the total carbon number of the ester compound is 20 or more.

In General Formula Ax, Y represents an m + n-valent linking group. Y is preferably an alkylene group which may have a substituent or an alkenylene group which may have a substituent. The number of carbon atoms in Y is preferably 8 or more, more preferably 10 or more, still more preferably 14 or more, still more preferably 20 or more, and even more preferably 30 or more. It is preferably 34 or more. Y may have a substituent, and the carbon number of Y here refers to the number including the carbon number of the substituent.
The ester compound having 20 or more carbon atoms represented by the general formula Ax is a polyvalent carboxylic acid moiety in which a part of the carboxyl group of a divalent or higher polyvalent carboxylic acid as described later is esterified with a monool. An ester compound is preferred. In this case, Y in the general formula Ax represents a divalent or higher polyvalent carboxylic acid residue. Here, the residue of the polyvalent carboxylic acid refers to a group constituting a part obtained by removing the carboxyl group from the polyvalent carboxylic acid. Y is preferably a residue of a succinic acid having a substituent having 8 or more carbon atoms or a residue of a multimer of unsaturated fatty acids having 16 or more carbon atoms. In particular, Y is a dimer acid residue or a trimer acid residue. It is preferably a group or an erucic acid dimer residue.

In the general formula Ax, examples of the substituent represented by R ^b include an alkyl group that may have a substituent, a cycloalkyl group that may have a substituent, and a substituent. Examples include an alkenyl group, an aryl group which may have a substituent, a heteroaryl group which may have a substituent, and the like. Specifically, an alkyl group having 1 to 70 carbon atoms (for example, methyl, ethyl, all of which are linear or branched propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl) , Dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, heneicosyl, docosyl, tricosyl, or tetracosyl); an alkenyl group having 2 to 35 carbon atoms (eg, propenyl, butenyl, pentenyl, hexenyl, heptenyl) Octenyl, nonenyl, decenyl, undecenyl, dodecenyl); a cycloalkyl group having 3 to 10 carbon atoms (eg, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl); 6 to 32 carbon atoms An aromatic ring group (for example, phenyl, naphthyl, biphenyl, phenanthryl, anthracenyl), a heterocyclic group (a heterocyclic residue containing at least one heteroatom selected from a nitrogen atom, an oxygen atom, and a sulfur atom) For example, pyridyl, pyrimidyl, triazinyl, thienyl, furyl, pyrrolyl, pyrazolyl, imidazolyl, triazolyl, thiazolyl, imidazolyl, oxazolyl, thiadialyl, oxadiazolyl, quinolyl, isoquinolyl); or a combination thereof. If possible, these substituents may further have one or more substituents. Examples of the substituents include alkoxy groups, alkoxycarbonyl groups, halogen atoms, ether groups, alkylcarbonyl groups, cyano groups. Group, thioether group, sulfoxide group, sulfonyl group, amide group and the like.

The substituent represented by R ^b is preferably an alkyl group or a substituent having an oxyalkylene structure. Especially, it is preferable that the substituent represented by ^Rb is an alkyl group which may have a substituent. R ^b preferably has 1 or more carbon atoms, more preferably 4 or more, further preferably 5 or more, still more preferably 6 or more, and particularly preferably 8 or more. preferable. The carbon number of R ^b is preferably 70 or less, more preferably 48 or less, further preferably 32 or less, and particularly preferably 24 or less.
The alkyl group represented by R ^b may be linear or branched, but branching is preferable from the viewpoint of lubricity under severe conditions such as high temperature and / or high pressure, and When used as an additive, it is also preferable from the viewpoint of solubility. R ^b preferably has no substituent other than the alkyl branched chain.
As the branched alkyl group, an alkyl group having one alkyl group having 1 to 12 carbon atoms as a branched chain is preferable, and an alkyl group having one alkyl group having 1 to 10 carbon atoms as a branched chain is more preferable. Among them, an alkyl group having 3 to 20 carbon atoms (total carbon number of 4 to 32) having one alkyl group having 1 to 12 carbon atoms at the 2-position as a branched chain is preferable, and an alkyl group having 1 to 10 carbon atoms as a branched chain. Is preferably an alkyl group having 4 to 14 carbon atoms having one at the 2-position (total carbon number of 5 to 24).

Furthermore, the substituent represented by R ^b preferably has an oxyalkylene structure. The substituent represented by R ^b preferably has a structure in which an alkyl group is directly linked to an oxyalkylene structure. The oxyalkylene structure preferably contains an oxyethylene group or an oxypropylene group, and may contain a polyoxyalkylene structure containing two or more oxyalkylene groups. The polyoxyalkylene structure preferably contains a polyoxyethylene group or a polyoxypropylene group. In addition, when ^Rb has an oxyalkylene structure, the carbon number of ^Rb mentioned above is a number also including the carbon number contained in an oxyalkylene structure.

In general formula Ax, m is an integer of 1 or more, and n is an integer of 1 or more. m and n are each independently preferably an integer of 1 to 3, more preferably 1 or 2, and even more preferably 1.

In general formula Ax, the carbon number + m + n of Y is 10 or more. The number of carbons in Y + m + n may be 10 or more, but the number of carbons in Y, m, and n are selected so that the number of carbons in the ester compound represented by the general formula Ax is 20 or more. The number of carbon atoms + m + n of Y is preferably 12 or more, more preferably 24 or more, and further preferably 36 or more.
In the general formula Ax, when m and n are 1, Y is preferably an alkylene group which may have a substituent. The number of carbon atoms of the alkylene group is preferably 8 or more, more preferably 10 or more, further preferably 22 or more, and particularly preferably 34 or more. In this case, the alkylene group represented by Y may be linear or branched, but is preferably branched. Moreover, the alkylene group represented by Y may have a substituent other than the alkyl branched chain, but is particularly preferably a branched alkylene group having no substituent other than the alkyl branched chain.

The ester compound having 20 or more carbon atoms is more preferably a compound represented by the following general formula Ay.

Here, in the general formula Ay, Y represents an m + n-valent linking group, Y carbon number + m + n is 10 or more, L is an alkylene group, m is an integer of 1 or more, and n is 1 or more. It is an integer, p is an integer of 1 or more, and R ^c represents a monovalent substituent.

Y in general formula Ay has the same meaning as Y in general formula Ax, and the preferred range is also the same. That is, the number of carbon atoms of Y in the general formula Ay is preferably 8 or more, more preferably 10 or more, further preferably 14 or more, still more preferably 20 or more, and 30 or more. More preferably, it is more preferably 34 or more. Y may have a substituent, and the carbon number of Y here refers to the number including the carbon number of the substituent. Y in the general formula Ay is preferably a residue of a succinic acid having a substituent having 8 or more carbon atoms or a residue of a multimer of unsaturated fatty acids having 16 or more carbon atoms, particularly a dimer acid residue. It is preferably a trimer acid residue or an erucic acid dimer residue.

The preferable ranges of m and n in the general formula Ay are the same as the preferable ranges of m and n in the general formula Ax.

L in the general formula Ay is an alkylene group. The alkylene group represented by L preferably has 2 to 4 carbon atoms, more preferably 2 or 3, and still more preferably 2. Further, p in the general formula Ay is more preferably an integer of 1 to 20, more preferably an integer of 1 to 10, still more preferably an integer of 1 to 8, and an integer of 1 to 4 Particularly preferred is an integer.

Examples of R ^c in the general formula Ay include a substituent represented by R ^b in the general formula Ax. R ^c is an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted alkenyl group, an optionally substituted aryl group or substituent. It is preferably a heteroaryl group that may have an alkyl group, and more preferably an alkyl group that may have a substituent. Among them, R ^c is preferably an alkyl group which may have a substituent, the carbon number thereof is preferably 1 or more, more preferably 4 or more, 5 or more More preferably, it is more preferably 6 or more, and particularly preferably 8 or more. Moreover, the carbon number of the alkyl group which may have a substituent is preferably 32 or less, and more preferably 24 or less.
Alkyl group represented by R ^c are may be branched may be linear, but preferably from lubricity point of view under extreme conditions that a branch is such a high temperature and / or pressure, also in the base oil When used as an additive, it is also preferable from the viewpoint of solubility.
As the branched alkyl group, an alkyl group having one alkyl group having 1 to 12 carbon atoms as a branched chain is preferable, and an alkyl group having one alkyl group having 1 to 10 carbon atoms as a branched chain is more preferable. Among them, an alkyl group having 3 to 20 carbon atoms (total carbon number of 4 to 32) having one alkyl group having 1 to 12 carbon atoms at the 2-position as a branched chain is preferable, and an alkyl group having 1 to 10 carbon atoms as a branched chain Is more preferably an alkyl group having 4 to 14 carbon atoms having one at the 2-position (total carbon number of 5 to 24).

Examples of the substituent that R ^c may further have include an alkoxy group, an alkoxycarbonyl group, a halogen atom, an ether group, an alkylcarbonyl group, a cyano group, a thioether group, a sulfoxide group, a sulfonyl group, an amide group, and the like. R ^c is preferably one having no substituent other than an alkyl branched chain.

Preferred examples of the ester compound contained in the lubricant composition of the present invention are shown below, but the ester compound used in the present invention is not limited to this.

In the case of having the substituent R ¹⁰¹ as in the ester compounds Aa-1 to Aa-11, R ¹⁰¹ may be substituted at the α-position or β-position of the carboxyl group. The ester compounds Aa-1 to Aa-11 may be a mixture of an ester compound in which R ¹⁰¹ is substituted at the α-position of the carboxyl group and an ester compound in which R ¹⁰¹ is substituted at the β-position.

The ester compound as described above is a partial ester compound of a polyvalent carboxylic acid in which a part of the carboxyl group of a polyvalent carboxylic acid having a valence of 2 or more is esterified with a monool, and an ester having 20 or more carbon atoms. A compound is preferred. Specifically, when the polyvalent carboxylic acid is a divalent carboxylic acid, it is preferably a partial ester compound in which only one of the two carboxyl groups is esterified with a monool. When the polyvalent carboxylic acid is a trivalent carboxylic acid, it is preferably a partial ester compound in which one or two of the three carboxyl groups are esterified with a monool.

<Polyvalent carboxylic acid>
The ester compound contained in the lubricant composition of the present invention is a partial ester compound of a polyvalent carboxylic acid in which a part of the carboxyl group of a divalent or higher polyvalent carboxylic acid is esterified with monool, A partial ester compound of several 20 or more is preferable. The carbon number of the divalent or higher valent carboxylic acid used in the present invention is preferably 10 or higher, more preferably 12 or higher, still more preferably 16 or higher, and more preferably 24 or higher. More preferably, it is particularly preferably 32 or more, and most preferably 36 or more. The divalent or higher polyvalent carboxylic acid used in the present invention is preferably a divalent carboxylic acid or a trivalent carboxylic acid, and particularly preferably a divalent carboxylic acid.

Examples of the divalent or higher polyvalent carboxylic acid include carboxylic acid derivatives having 10 or more carbon atoms, and multimers of unsaturated fatty acids. Examples of the carboxylic acid derivative having 10 or more carbon atoms include a succinic acid derivative having a substituent having 6 or more carbon atoms, a glutaric acid derivative having a substituent having 5 or more carbon atoms, an adipic acid derivative having a substituent having 6 or more carbon atoms, etc. Can be mentioned. In addition, as a carboxylic acid derivative, an acid anhydride, an acid halide, etc. are mentioned, An anhydride can be mentioned as a more preferable example.

Among these, as the divalent or higher polyvalent carboxylic acid having 10 or more carbon atoms, at least one selected from a succinic acid derivative having a substituent having 8 or more carbon atoms and a multimer of unsaturated fatty acids having 16 or more carbon atoms is used. It is preferable.
Examples of the succinic acid having a substituent having 8 or more carbon atoms include alkenyl succinic acid such as octenyl succinic acid, decenyl succinic acid, tetrapropenyl succinic acid (dodecenyl succinic acid), and octadecenyl succinic acid.
Examples of multimers of unsaturated fatty acids having 16 or more carbon atoms include dimer acids (dimers of unsaturated carboxylic acids having 18 carbon atoms), hydrogenated dimer acids, and trimer acids (of unsaturated carboxylic acids having 18 carbon atoms). Trimers), dimers of unsaturated carboxylic acids having 22 carbon atoms (for example, erucic acid dimer), and the like. That is, it is particularly preferable that the divalent or higher polyvalent carboxylic acid used in the present invention has 36 or more carbon atoms. Among these, dimer acid, hydrogenated dimer acid, trimer acid, and dimer of unsaturated carboxylic acid having 22 carbon atoms are preferably used from the viewpoint of solubility in base oil. Here, the dimer acid is an aliphatic or alicyclic dicarboxylic acid produced by dimerization of an unsaturated fatty acid (usually 18 carbon atoms) by polymerization or Diels-Alder reaction (in addition to most dimers, Many of them contain trimers, monomers and the like of several mol%), and among them, those whose main components are trimers are defined as trimer acids.
As specific examples of dimer acid or trimer acid, Tsunodim (registered trademark) 205, 216, 228, and 395 manufactured by Tsukino Food Industry Co., Ltd. are listed as examples of dimer acid. Tsunodim 345 and the like are listed as examples of trimer acid. It is done. As the dimer acid or trimer acid, products of Cognis, Unikema, and Croda may also be used. An example of a dimer of an unsaturated carboxylic acid having 22 carbon atoms is Cropa's Prepol 1004.

<Monoall>
The monool may have 1 or more carbon atoms, preferably 4 or more, more preferably 5 or more, still more preferably 6 or more, and particularly preferably 8 or more. The carbon number of the monool is preferably 70 or less, more preferably 48 or less, further preferably 32 or less, and particularly preferably 24 or less. The monool is preferably an aliphatic monool, more preferably having a branched alkyl chain, and particularly preferably having a branched alkyl chain having 1 to 12 carbon atoms.

Monools suitable for the present invention include, for example, methanol, ethanol, butanol, isobutanol, pentanol, propanol, hexanol, 2-ethylhexanol, 2-hexyloctanol, 2-octyldecanol, heptanol, octanol, decanol, dodecanol. Hexadecanol, 2-heptylundecanol, eicosadecanol, phytosterol, isostearyl alcohol, stearyl alcohol, cetol, behenol and the like. The monool used in the present invention preferably further has an oxyalkylene structure. Examples of monools having an oxyalkylene structure include the alkylene oxide adducts of monools described above.

When the monool used in the present invention has an oxyalkylene structure, the monool is more preferably represented by the following general formula (3).

Here, in the general formula (3), Ra represents an alkyl group which may have ^a substituent, ^a cycloalkyl group which may have a substituent, an alkenyl group which may have a substituent, or a substituent. An aryl group which may have or a heteroaryl group which may have a substituent, and X ^a1 and X ^a2 each independently represent a hydrogen atom, a halogen atom or an alkyl group; Na1 represents an integer of 2 to 4, and na2 represents an integer of 1 to 20. A plurality of X ^a1 may be the same or different, and a plurality of X ^a2 may be the same or different. When na2 is 2 or more, a plurality of —O (CX ^a1 X ^a2 ) _na1 — may be the same or different.

The number of carbon atoms in the alkyl group portion of the alkyl group which may have a substituent represented by ^Ra is preferably 1 to 32, more preferably 4 to 32, and 5 to 24. Is more preferable. The alkyl group represented by R ^a may be linear or branched, but branching is also preferable from the viewpoint of lubricity under severe conditions such as high temperature and / or high pressure. When used as an additive, it is also preferable from the viewpoint of solubility.

The carbon number of the alkenyl group part of the alkenyl group which may have a substituent represented by ^Ra is preferably 2 to 32, more preferably 4 to 32, and 5 to 24. Is more preferable. The alkenyl group represented by R ^a may be linear, branched or cyclic.

The number of carbon atoms in the aryl group portion of the aryl group or heteroaryl group which may have a substituent represented by R ^a is preferably 6 to 32, and more preferably 6 to 24. Examples of the aryl group represented by ^Ra include a phenyl group and a naphthyl group, and among them, a phenyl group is particularly preferable. Examples of the heteroaryl group represented by ^Ra include imidazolyl, pyridyl, quinolyl, furyl, thienyl, benzoxazolyl, indolyl, benzimidazolyl, benzthiazolyl, carbazolyl, azepinyl Can be illustrated. The hetero atom contained in the heteroaryl group is preferably an oxygen atom, a sulfur atom, or a nitrogen atom.

Especially, in General formula (3), it is more preferable that ^Ra is an alkyl group which may have ^a substituent. Here, the alkyl group is preferably a branched alkyl group. More preferably, X ^a1 and X ^a2 are each independently a hydrogen atom or an alkyl group.
As the branched alkyl group, an alkyl group having one alkyl group having 1 to 12 carbon atoms as a branched chain is preferable, and an alkyl group having one alkyl group having 1 to 10 carbon atoms as a branched chain is more preferable. Among them, an alkyl group having 3 to 20 carbon atoms (total carbon number of 4 to 32) having one alkyl group having 1 to 12 carbon atoms at the 2-position as a branched chain is preferable, and an alkyl group having 1 to 10 carbon atoms as a branched chain. Is more preferably an alkyl group having 4 to 14 carbon atoms having one at the 2-position (total carbon number of 5 to 24).

In general (3), na1 is preferably an integer of 2 to 4, more preferably 2 or 3, and even more preferably 2. Na2 is more preferably an integer of 1 to 20, more preferably an integer of 1 to 10, still more preferably an integer of 1 to 8, and an integer of 1 to 4. Is particularly preferred.

Examples of the substituent that ^Ra may have include an alkoxy group, an alkoxycarbonyl group, a halogen atom, an ether group, an alkylcarbonyl group, a cyano group, a thioether group, a sulfoxide group, a sulfonyl group, an amide group, and the like. Although ^Ra is mentioned, it is preferable that ^Ra does not have a substituent other than an alkyl branched chain.

(Esterification reaction mixture)
In addition to the partial ester compound of polyvalent carboxylic acid in which a part of the carboxyl group of the divalent or higher polyvalent carboxylic acid as described above is esterified with monool, A complete ester compound of a carboxylic acid, which may further contain a complete ester compound having 20 or more carbon atoms. Here, the complete ester compound of polyvalent carboxylic acid is an ester compound in which all carboxyl groups in one molecule of divalent or higher polyvalent carboxylic acid are esterified with monool. The lubricant composition of the present invention may contain a divalent or higher polyvalent carboxylic acid in which all of the carboxyl groups in one molecule of the polyvalent carboxylic acid are not esterified. That is, the lubricant composition of the present invention may contain a mixture of a partial ester compound of a polyvalent carboxylic acid and a complete ester compound of a polyvalent carboxylic acid. A mixture of an ester compound and a polyvalent carboxylic acid may be included.

A mixture of a partial ester compound of a polyvalent carboxylic acid, a polyvalent carboxylic acid complete ester compound and / or a polyvalent carboxylic acid is obtained by mixing an isolated partial ester compound, an isolated complete ester compound and / or a polyvalent carboxylic acid. A mixed mixture may be used, but an esterification reaction mixture of a divalent or higher polyvalent carboxylic acid and a monool may also be used. Specifically, by reacting a monool with a polyvalent carboxylic acid having the same reactivity, all the carboxyl groups in one molecule of the polyvalent carboxylic acid in addition to the partial ester compound are esterified with the monool. A mixture of the carboxylic acid complete ester compound and the raw material polycarboxylic acid remaining without being esterified can be obtained. For example, when a monool is reacted with a divalent carboxylic acid such as adipic acid, sebacic acid or dimer acid, in addition to a monoester compound having one carboxyl group and one ester bond, An esterification reaction mixture in which a complete ester compound in which all carboxyl groups in one molecule of a carboxylic acid are esterified is mixed is obtained. In the present invention, such a mixture may be used as it is. When the lubricant composition of the present invention contains an esterification reaction mixture, the ratio of the number of ester bonds to the total number of ester bonds and carboxyl groups in all molecules of the esterification reaction mixture is preferably 40 to 95%. 55 to 85% is more preferable, and 60 to 80% is more preferable. That is, in the esterification reaction mixture, it is preferable that 40 to 95% of all carboxyl groups in all molecules of divalent or higher polyvalent carboxylic acid are esterified with monool, and 55 to 85%. It is more preferable that the carboxyl group is esterified with monool, and it is more preferable that 60 to 80% of the carboxyl groups are esterified with monool.

The ratio of the number of ester bonds to the total number of ester bonds and carboxyl groups in the esterification reaction mixture can be calculated by measuring ¹ H-NMR (Nuclear Magnetic Resonance).
For example, when the esterification reaction mixture contains a polyvalent carboxylic acid, a partial ester compound, and a complete ester compound, the polyvalent carboxylic acid or partial ester compound having a structure represented by the following formula (Cx), At least a partial ester compound or a complete ester compound having a structure represented by the formula (Cy) is included. In such a case, the ratio of the number of ester bonds in the total molecule of the esterification reaction mixture can be calculated by the integral value of ¹ H-NMR (Hb / Ha) × 100. In the following formulas (Cx) and (Cy), Rx is a remaining group obtained by removing one (COOHCH ₂ —) group from a polyvalent carboxylic acid or partial ester compound. In the following formula (Cy), Ry is the remaining group obtained by removing the (—CH ₂ OH) group from the monool. Ha and Hb each independently represent a hydrogen atom.

The esterification reaction mixture is preferably obtained by charging polyvalent carboxylic acid and monool in a molar ratio of carboxyl group / hydroxyl group of 1 / 0.5 to 1 / 0.95 and carrying out esterification reaction.

The divalent or higher polyvalent carboxylic acid may be a divalent or higher polyvalent carboxylic acid derivative. When an acid anhydride is used as the polyvalent carboxylic acid derivative, the monoester is reacted with 1 equivalent of monool. A compound (partial ester compound) can be obtained. For example, an alkenyl succinic acid monoester can be obtained by reacting the alkenyl succinic anhydride with one equivalent of monool. The monoester compound obtained when the acid anhydride is used is not mixed with a polycarboxylic acid complete ester compound or a polycarboxylic acid. In the present invention, only such a monoester compound is esterified. It can also be used as a mixture. Moreover, even when an acid anhydride is used as the polyvalent carboxylic acid derivative, a mixture of a monoester compound and a diester compound can be obtained by reacting the acid anhydride with more than 1 equivalent of monool. .

(Ingredients other than the ester compound of the lubricant composition)
The present invention relates to a lubricant composition containing at least the above-described ester compound having 20 or more carbon atoms. In addition to the above-described ester compound having 20 or more carbon atoms, various additives and / or media can be further added to the lubricant composition of the present invention.

The lubricant composition of the present invention preferably further contains a medium. Specifically, the total amount of the lubricant composition includes 0.1 to 10% by mass of the ester compound or esterification reaction mixture and 60 to 99.9% by mass of the medium with respect to the total mass of the lubricant composition. On the other hand, it is preferable to contain 0 to 39.9% by mass of other components other than the ester compound or esterification reaction mixture and the medium.

(Medium)
Media (also referred to as base oil) include mineral oils, oil compounds, polyolefin oils (eg polyalphaolefins), silicone oils, ether oils (eg perfluoropolyether oils, diphenyl ether derivatives), ester oils (eg aromatic ester oils, Monovalent fatty acid ester, divalent fatty acid diester, polyol ester lubricating oil). Especially, it is preferable that a medium is at least 1 sort (s) chosen from mineral oil, polyolefin oil, and ester oil.

In the present invention, the “medium” means all the media generally called “fluid liquids”. However, it is not necessary to be liquid at room temperature or the temperature used, and any form of material such as solid and gel can be used in addition to liquid. There is no restriction | limiting in particular about the medium utilized in this invention, According to a use, it can select from various liquids. Regarding the medium that can be used in the present invention, the description in paragraphs 0067 to 0096 of JP2011-89106A can be referred to. The kinematic viscosity at 40 ° C. of the medium is preferably from 1 ~ 500mm ² / s, more preferably ^{1.5 ~ 200mm 2 / s, 2} ~ 50mm 2 / s is more preferable.

The viscosity index of the medium is preferably 90 or more, more preferably 105 or more, and still more preferably 110 or more. The viscosity index of the medium is preferably 160 or less. By setting the viscosity index within the above range, viscosity-temperature characteristics, thermal / oxidative stability, and volatilization prevention properties are improved, and wear prevention properties are improved. The viscosity index referred to in the present invention means a viscosity index measured according to JIS K 2283-1993.

(Other components other than ester compounds and media)
A compound preferable as the component other than the ester compound and the medium, that is, a preferable additive to the lubricant composition of the present invention is a compound containing at least one selected from zinc, molybdenum, sulfur and phosphorus as a constituent element. Such compounds have functions such as friction modifiers, antiwear agents, and antioxidants. The compound containing at least one of zinc, molybdenum, sulfur and phosphorus as a constituent element means a compound which may contain zinc, molybdenum, sulfur and phosphorus in any state. Specific examples include compounds containing zinc, molybdenum, sulfur, and phosphorus as simple substances (oxidation number 0), ions, complexes, and the like. Examples of such compounds include organic molybdenum compounds, inorganic molybdenum compounds, organic zinc compounds, (phosphite) phosphoric acid derivatives, organic sulfur compounds, and the like. Of these, organic molybdenum compounds and organic zinc compounds are preferred.

Further, only one compound containing at least one selected from zinc, molybdenum, sulfur and phosphorus as a constituent element may be added to the lubricant composition of the present invention, and two or more compounds of the lubricant of the present invention may be used. It may be added to the composition. When adding two or more compounds containing at least one selected from zinc, molybdenum, sulfur and phosphorus as a constituent element to the lubricant composition of the present invention, an organic molybdenum compound, an inorganic molybdenum compound, an organic zinc compound, It is preferable to combine two or more of (sub) phosphoric acid derivatives and organic sulfur compounds, and it is more preferable to combine organic molybdenum compounds and organic zinc compounds.

Hereinafter, preferred embodiments of the organic molybdenum compound, the inorganic molybdenum compound, the organic zinc compound, the (phosphorous) phosphoric acid derivative, and the organic sulfur compound will be described.

Examples of the organic molybdenum compound used as an additive in the lubricant composition include organic molybdenum compounds containing phosphorus such as molybdenum dithiophosphate (sometimes referred to as MoDTP). As another organic molybdenum compound, an organic molybdenum compound containing sulfur such as molybdenum dithiocarbamate (sometimes referred to as MoDTC) can be given. Examples of the organic molybdenum compound containing sulfur include sulfurized oxymolybdenum-N, N-di-octyldithiocarbamate (C ₈ -Mo (DTC)), sulfurized oxymolybdenum-N, N-di-tridecyldithiocarbamate ( C ₁₆ -Mo (DTC)) and the like are preferable.

Examples of other sulfur-containing organic molybdenum compounds include complexes of inorganic molybdenum compounds and sulfur-containing organic compounds. Examples of the inorganic molybdenum compound used in the organic molybdenum compound that is a complex of an inorganic molybdenum compound and a sulfur-containing organic compound include molybdenum oxides such as molybdenum dioxide and molybdenum trioxide, orthomolybdic acid, paramolybdic acid, and (poly) sulfurization. Molybdic acid such as molybdic acid, metal salts of these molybdic acids, molybdates such as ammonium salts, molybdenum disulfide, molybdenum trisulfide, molybdenum pentasulfide, molybdenum sulfide such as polysulfide molybdenum, molybdenum sulfide, molybdenum sulfide Examples thereof include metal salts or amine salts, and molybdenum halides such as molybdenum chloride. Examples of the sulfur-containing organic compound used in the organic molybdenum compound that is a complex of an inorganic molybdenum compound and a sulfur-containing organic compound include alkyl (thio) xanthate, thiadiazole, mercaptothiadiazole, thiocarbonate, and tetrahydrocarbyl thiuram disulfide. Bis (di (thio) hydrocarbyl dithiophosphonate) disulfide, organic (poly) sulfide, sulfurized ester and the like.
Examples of other organic molybdenum compounds containing sulfur include complexes of sulfur-containing molybdenum compounds such as molybdenum sulfide and sulfurized molybdenum acid with alkenyl succinimides.

As the organic molybdenum compound, an organic molybdenum compound that does not contain phosphorus or sulfur as a constituent element can be used. Specific examples of organic molybdenum compounds that do not contain phosphorus or sulfur as constituent elements include molybdenum-amine complexes, molybdenum-succinimide complexes, molybdenum salts of organic acids, and molybdenum salts of alcohols. Amine complexes, molybdenum salts of organic acids and molybdenum salts of alcohols are preferred.

The inorganic molybdenum compound used as an additive in the lubricant composition is the same as that exemplified as the inorganic molybdenum compound used for the organic molybdenum compound that is a complex of the inorganic molybdenum compound and the sulfur-containing organic compound.

As the organic zinc compound used as an additive in the lubricant composition, zinc dithiophosphate (ZDTP) zinc diphosphate (ZDP) represented by the following formula is preferable.

In the above formula, Q ¹ , Q ² , Q ³ and Q ⁴ may be the same or different, and are each independently isopropyl, butyl, isobutyl, pentyl, isopentyl, neopentyl, hexyl, heptyl. Represents an alkyl group having 8 to 20 carbon atoms such as a group, octyl group, 2-ethylhexyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, misty group, palmityl group and stearyl group.

Specific examples of zinc dithiophosphate (ZDTP) represented by the above formula include zinc n-butyl-n-pentyldithiophosphate (C ₄ / C ₅ ZnDTP) and zinc di-2-ethylhexyldithiophosphate (C ₈ ZnDTP). Alternatively, zinc isopropyl-1-ethylbutyldithiophosphate (C ₃ / C ₆ ZnDTP) is preferable.

When an organic molybdenum compound is used in the lubricant composition of the present invention, the organic molybdenum compound is preferably contained in an amount of 10 to 1500 mg / L as a molybdenum content with respect to the total mass of the lubricant composition. More preferably, it is contained in an amount of 1000 mg / L, more preferably 100 to 800 mg / L.
When an organic zinc compound is used, it is preferable that the zinc content of the organic zinc compound is 50 to 10,000 mg / L, and 100 to 5000 mg / L is included with respect to the total mass of the lubricant composition. Is more preferable, and 200 to 1500 mg / L is more preferable.
By making the content of the organometallic compound such as the organomolybdenum compound and the organozinc compound in the lubricant composition within the above range, the stability of the lubricant composition can be improved, and severe conditions such as high temperature and / or high pressure can be achieved. The lubrication characteristics under the conditions can be improved, and the wear suppression ability can be exhibited.

Examples of the (sub) phosphoric acid derivative include, in addition to the above-mentioned zinc dithiophosphate (ZDTP) and zinc diphosphate (ZDP), phosphites, phosphate esters, tricresyl phosphate and other aromatic phosphate esters, phosphorus Aliphatic phosphate esters such as trialkyl acids can be exemplified as preferred examples. Of these, aromatic phosphate esters such as tricresyl phosphate and aliphatic phosphate esters such as trialkyl phosphate are more preferable.

As the organic sulfur compound, polysulfides are preferable, and dialkyl polysulfide is more preferable.

As other components other than the ester compound and the medium, in addition to the above compound, for example, a viscosity index improver (preferably polyalkyl (meth) acrylate, alkyl (meth) acrylate- (meth) acrylate copolymer having a polar group) Polymers, copolymers of butadiene, olefins or alkylated styrene), antioxidants (preferably hindered phenol compounds, sulfurized alkylphenol compounds, aromatic amine compounds, low sulfur peroxide decomposers, oil-soluble copper compounds), cleansers Agents (sulfate, phenate, carboxylate, phosphate and salicylate alkali metal salts or alkaline earth metal salts, (boric acid modified) succinimide, succinate ester), dispersant (preferably phenate, sulfonate, sulfurized phenate, salicylate) , Naphth Nates, stearates, carbamates, thiocarbamates, phosphorus derivatives, succinic acid derivatives (eg long chain substituted alkenyl succinic acid derivatives, succinimide derivatives, hydrocarbyl substituted succinic acid compounds, succinic acid esters, succinic acid ester amides), Mannich bases) Pour point depressants (preferably polymethacrylates, polyacrylates, polyarylamides, condensation products of haloparaffin waxes and aromatic compounds, vinyl carboxylate polymers and dialkyl fumarate, terpolymers of fatty acid vinyl esters and allyl vinyl ethers), Corrosion inhibitors (preferably thiadiazole), seal compatibilizers (preferably organic phosphates, aromatic esters, aromatic hydrocarbons, esters (eg butyl benzyl phthalate) and polybutenis Succinic anhydride), defoamers (preferably polydimethyl silicones), rust inhibitors, friction modifiers, mention may be made of anti-wear agents, and one or more selected from thickener.
By adding such an additive, a lubricant composition capable of exhibiting functions such as wear suppression can be obtained. Regarding the additives that can be used in the present invention, the description in paragraphs 0098 to 0165 of JP2011-89106A can be referred to.

(Properties of lubricant composition)
Lubricant composition of the present invention preferably has a kinematic viscosity at 40 ° C. or less 500 mm ² / s, more preferably 200 mm ² / s or less, more preferably at most 100 mm ² / s 50 mm ² / s or less is particularly preferable, and 5 to 50 mm ² / s is most preferable. Viscosity needs to be adjusted to an appropriate viscosity depending on the usage environment. In this specification, the kinematic viscosity at 40 ° C. of the lubricant composition is specifically a value measured in a constant temperature water bath at 40.0 ° C. using an Ubbelohde viscometer.

The lubricant composition of the present invention may be mixed with grease to prepare a grease composition. In such an embodiment, in order to ensure practical performance when adapted to the use of grease, a thickener or the like can be added as necessary within a range not impairing the object of the present invention. When adding a thickener, the thickener is preferably contained in an amount of 10 to 50% by mass based on the total mass of the grease composition. Hereinafter, additives that can be added when preparing the grease composition will be described.

Thickeners that can be added include soap-type thickeners such as metal soaps and composite metal soaps, benton, silica gel, and urea-type thickeners (urea compounds, urea / urethane compounds, urethane compounds, etc.). Any thickener such as a thickener can be used. 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, lithium soap and the like. Among these, lithium soap is preferable from the viewpoint of water resistance and thermal stability. Examples of the lithium soap include lithium stearate and lithium-12-hydroxystearate.

Further, examples of the urea thickener 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.

The grease composition can also contain a solid lubricant as an additive. Examples of solid lubricants include polytetrafluoroethylene, boron nitride, fullerene, graphite, fluorinated graphite, melamine cyanurate, molybdenum disulfide, Mo (molybdenum) -dithiocarbamate, antimony sulfide, and alkali (earth) metal boric acid. Examples include salts.

Also, the grease composition can contain a wax as an additive. 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.

In addition, benzotriazole, benzimidazole, thiadiazole and the like are known as metal deactivators, and these can be added.

A thickener can be added to the grease composition. 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.

(Method for producing lubricant composition)
The present invention is a method for producing a lubricant composition comprising a step of esterifying a part of a carboxyl group of a polyvalent carboxylic acid with a monool, wherein at least one ester bond and a carboxyl group are contained in one molecule. The present invention also relates to a method for producing a lubricant composition containing an ester compound having 20 or more carbon atoms. In the esterification step, it is preferable that an esterification reaction mixture is produced.

In the method for producing a lubricant composition, the esterification step is preferably a step of esterifying 40 to 95% of all carboxyl groups in all the polyvalent carboxylic acid molecules with monool. More preferably, it is a step of esterifying 55 to 85% of the carboxyl group with monool, and further preferably a step of esterifying 60 to 80% of the carboxyl group with monool.

In addition, the manufacturing method of the lubricant composition includes a step of isolating only the ester compound having 20 or more carbon atoms including at least one ester bond and a carboxyl group in one molecule after the esterification step. May be included. In the isolation step, the esterification reaction mixture is preferably purified by column chromatography.

(Step of esterification)
The step of esterification includes a step of dehydrating and condensing the above-described divalent or higher polyvalent carboxylic acid and monool. In the present invention, the reaction conditions are adjusted so that such dehydration condensation reaction does not occur with all carboxyl groups of the polyvalent carboxylic acid but occurs with some carboxyl groups. For example, in the esterification step, it is preferable to charge the polyvalent carboxylic acid and monool in a molar ratio of carboxyl group / hydroxyl group in a ratio of 1 / 0.5 to 1 / 0.95 for esterification reaction. Alternatively, the esterification reaction conditions may be adjusted so that a partial ester compound is formed by charging polyvalent carboxylic acid and monool at a carboxyl group / hydroxyl molar ratio of 1/1 to 1/10. When the monool remains after the reaction, it is preferable to remove the monool by a method such as distillation under reduced pressure.

The dehydration condensation reaction is preferably performed in the presence of a catalyst or without a catalyst. In addition, during the dehydration condensation, it is desirable to heat or to make an appropriate amount of a solvent azeotroped with water. Thereby, dehydration proceeds smoothly without coloring the esterification reaction mixture. This solvent is preferably a hydrocarbon solvent having a boiling point of 100 to 200 ° C., more preferably a hydrocarbon solvent having a boiling point of 100 to 170 ° C., and most preferably a hydrocarbon solvent having a boiling point of 110 to 160 ° C. Examples of these solvents include toluene, xylene, mesitylene and the like. The amount of the solvent added is preferably from 1 to 25% by weight, more preferably from 2 to 20% by weight, particularly preferably from 3 to 15% by weight, based on the total amount of the polyvalent carboxylic acid and monool, and from 5 to 12% by weight. preferable.

Although the reaction is accelerated by using the catalyst, it is preferable not to use it because the post-treatment of removing the catalyst is complicated and causes the coloring of the esterification reaction mixture. However, when used, normal conditions and procedures are used with normal catalysts. Regarding this, reference can be made to the references in JP-T 2001-501989, JP-A 2001-500509, JP-A 2001-507334, and JP-A 2002-509563.

After completion of the preparation, the reaction is performed at a liquid temperature of 120 to 250 ° C., preferably 130 to 230 ° C., more preferably 130 to 220 ° C., and particularly preferably 140 to 220 ° C. As a result, a solvent containing water is azeotroped, cooled at a cooling site such as Dean Stark, and becomes a liquid to separate water and the solvent. This water may be removed.

The reaction time is preferably 1 to 24 hours, more preferably 3 to 18 hours, still more preferably 5 to 18 hours, and most preferably 6 to 15 hours.

(Use of lubricant composition)
The lubricant composition of the present invention can be supplied, for example, between two sliding surfaces and used to reduce friction. The lubricant composition of the present invention can form a film on the sliding surface. Specific examples of the sliding surface material include structural structural carbon steel, nickel chrome steel material, nickel chrome molybdenum steel material, chrome steel material, chrome molybdenum steel material, aluminum chrome molybdenum steel material, stainless steel, Examples include multi-aging steel.

As the material of the sliding surface, various metals other than steel, or inorganic or organic materials other than metals are 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.
For the material of the sliding surface, reference can be made to the descriptions in paragraphs 0168 to 0175 of JP2011-89106A.

The lubricant composition of the present invention can be used for various applications. For example, grease lubricant, mold release agent, internal combustion engine oil, internal combustion engine oil, metal working (cutting) oil, bearing oil, combustion engine fuel, vehicle engine oil, gear oil, automotive operation Oil, Marine / Aircraft Lubricant, Machine Oil, Turbine Oil, Bearing Oil, Hydraulic Oil, Compressor / Vacuum Pump Oil, Refrigerator Oil, Metalworking Lubricant, Magnetic Recording Medium Lubricant, Micromachine Lubricant It can be used as a lubricant for artificial bone, shock absorber oil or rolling oil. It is also used for air conditioners and refrigerators with reciprocating and rotary hermetic compressors, automotive air conditioners and dehumidifiers, freezers, refrigerated warehouses, vending machines, showcases, chemical plant and other cooling devices. .

The lubricant composition of the present invention can also be used as a metal working lubricant that does not contain a chlorine compound. For example, when hot-rolling metal materials such as steel materials and Al (aluminum) alloys, or when performing processing such as cutting, aluminum cold rolling oil, cutting oil, grinding oil, drawing oil, press The lubricant composition of the present invention can be used as a metal processing oil such as a processing oil or a metal plastic processing oil. The lubricant composition of the present invention is a metal working oil composition that can be used as a deterrent for wear, breakage, and surface roughness particularly during high-speed and high-load machining, and for low-speed and heavy cutting such as broaching and gun drilling. It is also useful.
The lubricant composition of the present invention can be used for various grease lubricants, magnetic recording medium lubricants, micromachine lubricants, artificial bone lubricants, and the like. Further, since the elemental composition of the lubricant composition can be a carbohydrate, it can be used, for example, as an emulsifying, dispersing, or solubilizing agent. By using an edible oil such as sorbitan fatty acid ester containing polyoxyethylene ether widely used for cake mix, salad dressing, shortening oil, chocolate, etc., to obtain a high-performance lubricating oil that is completely harmless to the human body Can do. Such lubricating oil can be used for manufacturing equipment and medical equipment members of food production lines.
Furthermore, the lubricant composition of the present invention can be used as cutting oil or rolling oil by emulsifying and dispersing it in an aqueous system or by dispersing it in a polar solvent or a resin medium.

Moreover, the lubricant composition of the present invention can be used for various applications as a release agent. For example, polycarbonate resin, flame retardant polycarbonate resin, crystalline polyester resin which is the main component of image forming toner used in electrophotographic apparatus and electrostatic recording apparatus, various molding thermoplastic resin compositions and semiconductor encapsulating Used as a mold release agent for epoxy resin compositions.
Moreover, it can also be used as an antifouling agent that promotes the detachment of dirt adhering to the fiber product and prevents the fiber product from being soiled by being kneaded or applied in advance to a textile product such as clothing.

Hereinafter, the features of the present invention will be described more specifically with reference to examples and comparative examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

(Synthesis of ester compound Aa-1)
One equivalent of 2-ethylhexanol was added dropwise to octenyl succinic anhydride (manufactured by Shin Nippon Rika Co., Ltd., Ricacid OSA) over 30 minutes, reacted at room temperature for 1 hour, and further reacted at 50 ° C. for 3 hours. The reaction was carried out without solvent. The product was purified by column chromatography to obtain partial ester compound Aa-1. In addition, although a partial ester compound with high purity can be obtained even under the above-described reaction conditions, it is possible to purify only the partial ester compound by purification by column chromatography.

(Synthesis of ester compound Aa-2)
Partial ester compound Aa-2 was obtained in the same manner as ester compound Aa-1, except that 2- (2-ethylhexyloxy) ethanol was used instead of 2-ethylhexanol.

(Synthesis of ester compound Aa-4)
Partial ester compound Aa-4 was obtained using the same method as ester compound Aa-1 except that dodecenyl succinic anhydride (manufactured by Shin Nippon Chemical Co., Ltd., Ricacid DDSA) was used instead of octenyl succinic anhydride.

(Synthesis of ester compound Aa-6)
Ester compound Aa- except that dodecenyl succinic anhydride (manufactured by Nippon Nippon Chemical Co., Ltd., Ricacid DDSA) is used instead of octenyl succinic anhydride, and 2-((2-ethylhexyl) oxyethoxy) ethanol is used instead of 2-ethylhexanol. Partial ester compound Aa-6 was obtained using the same procedure as in Example 1.

(Synthesis of ester compound Ab-1)
0.5 equivalent of 2-ethylhexanol was mixed with the amount of carboxylic acid of dimer acid (Tsunodim 395, manufactured by Tsukino Foods Co., Ltd.) and reacted at 220 ° C. for 5 hours under a nitrogen stream. The product was purified by column chromatography to obtain partial ester compound Ab-1.

(Synthesis of ester compound Ab-2)
Partial ester compound Ab-2 was obtained in the same manner as ester compound Ab-1, except that 2- (2-ethylhexyloxy) ethanol was used instead of 2-ethylhexanol.

(Synthesis of ester compound Ab-3)
Partial ester compound Ab-3 was obtained in the same manner as ester compound Ab-1, except that 2-((2-ethylhexyl) oxyethoxy) ethanol was used in place of 2-ethylhexanol.

(Synthesis of ester compound Ab-11)
Partial ester compound Ab-11 was obtained in the same manner as ester compound Ab-1, except that polyethylene glycol monoisostearyl ether (average number of oxyethylene groups 6) was used instead of 2-ethylhexanol.

(Synthesis of ester compound Ac-1)
Partial ester compound Ac-1 was obtained using the same method as ester compound Ab-2, except that sebacic acid was used instead of dimer acid.

(Synthesis of ester compound Ad-3)
Partial ester compound Ad-3 was obtained in the same manner as ester compound Ab-3, except that erucic acid dimer (manufactured by Croda, Pripol 1004) was used instead of dimer acid.

As a comparative compound, an ester compound having no carboxyl group or an ester compound having less than 20 carbon atoms was used.
(Ester Compound X1) Bis (2-ethylhexyl) octenyl succinate
(Ester compound X2) Bis (2- (ethylhexyloxy) ethyl) octenyl succinate
(Ester compound X3) Dimer acid bis (2- (2-ethylhexyloxy) ethyl)
(Ester compound X4) Bis (2- (2-ethylhexyloxy) ethyl) sebacate
(Ester compound X5) Sebacic acid mono (2-ethylhexyl) carbon number 18

(Examples 1 to 15 and Comparative Examples 1 to 6)
An ester compound was added to the base oil so as to have the addition amount shown in Table 1, and lubricant compositions of Examples 1 to 15 and Comparative Examples 1 to 6 were obtained. The obtained lubricant composition was evaluated by the following methods.

(Evaluation)
(Coefficient of friction)
About the lubricant composition of each Example and the comparative example, the friction coefficient was measured using the vibration-type friction-wear tester (The product made by Optimol Instruments Prutechnik GmbH, SRV 4). In the measurement of the friction coefficient, at a temperature of 40 ° C., a measurement condition (condition 1) with a vibration frequency of 50 Hz, a load of 150 N, and an amplitude of 2 mm and at a temperature of 80 ° C., a measurement condition with a vibration frequency of 50 Hz, a load of 300 N, and an amplitude of 2 mm (condition 2). ) Were subjected to a friction and wear test for 1 hour, and the coefficient of friction was measured after 30 minutes. A 10 mm SUJ-2 ball and a lower test piece 24 mm SUJ-2 disc were used for the upper test piece in the frictional wear test. The observed coefficient of friction was evaluated according to the following criteria. The results are shown in Table 1 below.
The other evaluation results were normalized by setting the friction coefficient in Condition 2 of Comparative Example 1 to 100% and evaluated as follows. The smaller the value, the smaller the coefficient of friction, indicating better lubricating properties. It was judged that a, b, and c had a large reduction in the friction coefficient, and that the improvement effect was great. In the tests of conditions 1 and 2, an evaluation of c or higher was regarded as a pass evaluation.
a: Less than 60% b: 60% or more and less than 70% c: 70% or more and less than 90% d: 90% or more and less than 100% e: 100% or more (standard)

Mineral oil: Super oil N46 (40 ° C kinematic viscosity 46mm ² / s) manufactured by JX Nippon Oil & Gas Company
PAO (poly-α-olefin oils): Anderol Inc. Anderol FGC46 (40 ℃ kinematic viscosity 46 mm ² / s)

As shown in Table 1, it can be seen that the lubricant compositions obtained in the examples have a small friction coefficient in both conditions 1 and 2 and can exhibit good lubricating performance. On the other hand, it can be seen that the lubricant composition obtained in the comparative example has a large coefficient of friction and is inferior in lubricating properties.

Furthermore, a mixture containing a complete ester compound in which all of the carboxylic acid was esterified in addition to the ester compound was obtained by the following method.

(Preparation of mixture Ab-2m1)
0.5 equivalent of 2- (2-ethylhexyloxy) ethanol was mixed with the amount of carboxylic acid of dimer acid (manufactured by Tsukino Foods Co., Ltd., Tsunodim 395) and reacted at 220 ° C. for 5 hours in a nitrogen stream. The remaining 2- (2-ethylhexyloxy) ethanol was removed by distillation under reduced pressure to obtain a mixture Ab-2m1 containing the ester compound Ab-2. As a result of confirmation by NMR (Nuclear Magnetic Resonance), on average, Ab-2m1 was 43% of the carboxylic acid esterified. Moreover, it confirmed that the partial ester compound contained by the high performance liquid chromatography (HPLC) or the gas chromatography.

(Preparation of mixture Ab-2m2)
0.6 equivalent of 2- (2-ethylhexyloxy) ethanol was mixed with the amount of carboxylic acid of dimer acid (manufactured by Tsukino Foods Co., Ltd., Tsunodim 395), and reacted at 220 ° C. for 5 hours in a nitrogen stream. The remaining 2- (2-ethylhexyloxy) ethanol was removed by distillation under reduced pressure to obtain a mixture Ab-2m2 containing the ester compound Ab-2. As a result of confirmation by NMR, 52% of Ab-2m2 was esterified on average among carboxylic acids.

(Preparation of mixture Ab-2m3)
0.75 equivalents of 2- (2-ethylhexyloxy) ethanol was mixed with the amount of carboxylic acid of dimer acid (Tsunoda Foods Co., Ltd., Tsunodim 395), and reacted at 220 ° C. for 5 hours in a nitrogen stream. The remaining 2- (2-ethylhexyloxy) ethanol was removed by distillation under reduced pressure to obtain a mixture Ab-2m3 containing the ester compound Ab-2. As a result of confirmation by NMR, an average of 65% of the carboxylic acid was esterified with Ab-2m3.

(Preparation of mixture Ab-2m4)
0.85 equivalent of 2- (2-ethylhexyloxy) ethanol was mixed with the amount of carboxylic acid of dimer acid (Tsunodim 395 manufactured by Tsukino Foods Co., Ltd.), and reacted at 220 ° C. for 5 hours under a nitrogen stream. The remaining 2- (2-ethylhexyloxy) ethanol was removed by distillation under reduced pressure to obtain a mixture Ab-2m4 containing the ester compound Ab-2. As confirmed by NMR, an average of 75% of the carboxylic acid was esterified with Ab-2m4.

(Preparation of mixture Ab-2m5)
0.95 equivalent of 2- (2-ethylhexyloxy) ethanol was mixed with the amount of carboxylic acid of dimer acid (manufactured by Tsukino Foods Co., Ltd., Tsunodim 395) and reacted at 220 ° C. for 5 hours under a nitrogen stream. The remaining 2- (2-ethylhexyloxy) ethanol was removed by distillation under reduced pressure to obtain a mixture Ab-2m5 containing the ester compound Ab-2. As a result of confirmation by NMR, 92% of the carboxylic acid was esterified on average in Ab-2m5.

(Examples 21 to 25)
In addition to the ester compound, a mixture containing a complete ester compound in which all of the carboxylic acid was esterified was mixed with the base oil so as to have an addition amount shown in Table 2 to prepare a lubricant composition. The coefficient of friction was evaluated using the same method as in Example 1.

As shown in Table 2, even when using a mixture containing a complete ester compound in which all of the carboxylic acid is esterified in addition to the ester compound, the coefficient of friction is reduced, It has been found that it exhibits lubricating properties.

(Examples 31 and 32)
Lubricant composition using base oil obtained by adding molybdenum dialkyldithiocarbamate (MoDTC) with Mo concentration of 800 mg / L and zinc dialkyldithiophosphate (ZnDTP) with Zn concentration of 800 mg / L to Super Oil N46 manufactured by JX Nippon Mining & Metals as base oil A product was prepared. The coefficient of friction was evaluated using the same method as in Example 1.

As shown in Table 3, the lubricant compositions obtained in the examples show good lubricating properties even when used in combination with existing additives.

(Examples 41 and 42 and Comparative Example 41)
The ester compound shown in the table below and grease 1 (Mobil SHC Grease 460WT) were mixed to obtain a grease composition. The friction coefficient was evaluated using the same method as in Example 1 except that the other evaluation results were normalized by setting the friction coefficient in Condition 2 of Comparative Example 41 to 100%.

Grease 1: Mobile SHC Grease 460WT

As shown in Table 4, the grease composition obtained in the examples has good friction characteristics.

Claims

A lubricant composition containing an ester compound having 20 or more carbon atoms containing at least one ester bond and a carboxyl group in one molecule.
The lubricant composition according to claim 1, wherein the number of ester bonds contained in one molecule of the ester compound having 20 or more carbon atoms is 1 to 3.
The lubricant composition according to claim 1 or 2, wherein the number of carboxyl groups contained in one molecule of the ester compound having 20 or more carbon atoms is 1 to 3.
The number of ester bonds contained in one molecule of the ester compound having 20 or more carbon atoms is 1, and the number of carboxyl groups contained in one molecule of the ester compound having 20 or more carbon atoms is 1. 4. The lubricant composition according to any one of items 1 to 3.
The lubricant composition according to any one of claims 1 to 4, wherein the ester compound having 20 or more carbon atoms has an oxyalkylene structure.
The lubricant composition according to claim 1, wherein the ester compound having 20 or more carbon atoms is represented by the following general formula Ax;

In the general formula Ax, Y represents an m + n-valent linking group, Y a carbon number + m + n is not less than 10, m is an integer of 1 or more, n is an integer of 1 or more, R b is a monovalent Represents a substituent.
The lubricant composition according to claim 6, wherein the carbon number of Y in the general formula Ax is 8 or more.
The lubricant composition according to claim 6 or 7, wherein Y in the general formula Ax is a residue of a succinic acid having a substituent having 8 or more carbon atoms or a residue of a multimer of unsaturated fatty acids having 16 or more carbon atoms. .
The lubricant composition according to any one of claims 6 to 8, wherein the carbon number of Y in the general formula Ax is 34 or more.
The lubricant composition according to any one of claims 6 to 9, wherein R b in the general formula Ax has 8 or more carbon atoms.
The lubricant composition according to claim 1, wherein the ester compound having 20 or more carbon atoms is represented by the following general formula Ay;

In general formula Ay, Y represents an m + n-valent linking group, Y carbon number + m + n is 10 or more, L is an alkylene group, m is an integer of 1 or more, and n is an integer of 1 or more. , P is an integer of 1 or more, and R c represents a monovalent substituent.
The lubricant composition according to any one of claims 1 to 11, which further comprises a complete ester compound of a polyvalent carboxylic acid and having 20 or more carbon atoms.
The lubricant composition according to any one of claims 1 to 12, further comprising a compound containing as a constituent element at least one selected from zinc, molybdenum, sulfur and phosphorus.
A method for producing a lubricant composition comprising a step of esterifying a part of a carboxyl group of a polyvalent carboxylic acid with monool, wherein carbon containing at least one ester bond and one carboxyl group in one molecule The manufacturing method of the lubricant composition containing the ester compound whose number is 20 or more.
The method for producing a lubricant composition according to claim 14, wherein the esterifying step is a step of esterifying 40 to 95% of all carboxyl groups in all molecules of the polyvalent carboxylic acid with monool. .