JP6527248B2 - Lubricant composition and method for producing lubricant composition - Google Patents

Description

  The present invention relates to lubricant compositions. More specifically, the present invention relates to a lubricant composition containing a specific ester compound and capable of exhibiting low friction.

    The lubricant composition generally comprises a base oil and various additives. As a base oil, there are mineral oil obtained from crude oil, ester-based oil chemically synthesized, fluorine oil, poly alpha-olefin oil and the like. Among these, ester-based oils are suitably used for jets, 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.

  Ester-based oils are known to be used as base oils or additives. For example, a monoester having 20 or less carbon atoms obtained from the reaction of an aliphatic monocarboxylic acid and a monohydric alcohol; a diester obtained from the reaction of an aliphatic dibasic acid and a monohydric alcohol; a polyhydric alcohol and an aliphatic carboxylic acid And various esters are disclosed, such as polyol esters obtained from the reaction with (1) and composite esters obtained from the reaction with polyols, polybasic acids, and aliphatic monocarboxylic acids (Patent Documents 1 to 9).

JP, 2002-097482, A JP, 2005-154726, A JP, 2005-232434, A JP 2005-213377 JP, 2005-232470, A Japanese Patent Publication No. 2001-501989 Japanese Patent Publication No. 2001-500549 Japanese Patent Application Publication No. 2001-507334 Japanese Patent Application Publication No. 2002-530476

  In recent years, with the diversification and advancement of the industrial field, lubricant compositions are required to have high lubricating performance. In addition, lubricant compositions are required to exhibit good friction characteristics in various temperature 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 investigations to solve the above problems, the present inventor contains an ester compound having a specific structure and carbon number, and thus can exhibit good friction characteristics in various temperature and load regions. It has been found that an agent composition is obtained.
That is, the above-mentioned subject is solved by the present invention of the following composition.

[1] A lubricant composition containing an ester compound having 20 or more carbon atoms which contains at least one ester bond and at least one carboxyl group in one molecule.
[2] The lubricant composition according to [1], wherein the number of ester bonds contained in one molecule of an 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 an 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 [1 ]-The lubricant composition in 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 a carbon number of 20 or more is represented by the following general formula Ax;
In the general formula Ax, Y represents an m + n valent linking group, the carbon number of Y + m + n is 10 or more, m is an integer of 1 or more, n is an integer of 1 or more, R ^b is monovalent Represents a substituent.
[7] The lubricant composition according to [6], wherein the carbon number of Y in the general formula Ax is 8 or more.
[8] In the general formula Ax, Y is a residue of a succinic acid having a substituent of 8 or more carbon atoms or a residue of a multimer of unsaturated fatty acids having 16 or more carbon atoms. [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 the carbon number of R ^b in the general formula Ax is 8 or more.
[11] The lubricant composition according to [1], wherein the ester compound having a carbon number of 20 or more is represented by the following general formula Ay:
In the general formula Ay, Y represents an m + n valent linking group, the carbon number of Y + m + n is 10 or more, L is an alkylene group, m is an integer of 1 or more, n is an integer of 1 or more, And 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], which is a complete ester compound of a polyvalent carboxylic acid and further contains a complete ester compound having 20 or more carbon atoms.
[13] The lubricant composition according to any one of [1] to [12], which further contains a compound containing at least one selected from zinc, molybdenum, sulfur and phosphorus as a constituent element.
[14] A method for producing a lubricant composition, comprising the step of esterifying a part of carboxyl groups of a polyvalent carboxylic acid with a monool, which comprises at least one ester bond and one carboxyl group in one molecule. The manufacturing method of the lubricant composition containing the ester compound of carbon number 20 or more which each contains.
[15] The step of esterifying is a step of esterifying 40 to 95% of carboxyl groups of all carboxyl groups in all polyvalent carboxylic acid molecules with monool with the lubricant composition described in [14] Production method.

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

  Hereinafter, the present invention will be described in detail. The description of the configuration requirements described below may be made based on typical embodiments and specific examples, but the present invention is not limited to such embodiments. In addition, the numerical range represented using "-" in this specification means the range which includes the numerical value described before and after "-" as a lower limit and an upper limit.

(Lubricant composition)
The lubricant composition of the present invention contains, in one molecule, an ester compound having 20 or more carbon atoms which contains at least one ester bond and at least one carboxyl group. 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 ester compound molecule is 1 to The number is preferably 3, more preferably 1 or 2, and still more preferably 1. Further, one molecule of an 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 ester compound molecule is The number 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 an 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 carbon number of the ester compound contained in the lubricant composition of the present invention is 20 or more, preferably 24 or more, more preferably 28 or more, and still more 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 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. The oxyalkylene structure refers to a structure in which an oxygen atom is introduced into the 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. In addition, the ester compound may contain a polyoxyalkylene structure containing an oxyalkylene group repeatedly two or more times. 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 the general formula Ax, Y represents an m + n valent linking group, the carbon number of Y + 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 such that the total carbon number of the ester compound is 20 or more.

In the 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 carbon number of Y is preferably 8 or more, more preferably 10 or more, still more preferably 14 or more, still more preferably 20 or more, and still more preferably 30 or more. Preferably, it is 34 or more. Y may have a substituent, and the carbon number of Y as referred to herein means the number including the carbon number of the substituent.
The ester compound having a carbon number of 20 or more represented by the general formula Ax is a part of a polyvalent carboxylic acid in which a part of the carboxyl group of a divalent or higher polyvalent carboxylic acid as described later is esterified with monool. It is preferably an ester compound. In this case, Y in the general formula Ax represents a residue of a divalent or higher polyvalent carboxylic acid. Here, the residue of a polyvalent carboxylic acid refers to a group constituting a portion obtained by removing a carboxyl group from a polyvalent carboxylic acid. Y is preferably a residue of succinic acid having a substituent of 8 or more carbon atoms or a residue of a multimer of unsaturated fatty acid having 16 or more carbon atoms, and in particular, Y is a dimer acid residue, trimer acid residue It is preferably a group or an erucic acid dimer residue.

The substituent represented by R ^b in the general formula Ax may have, for example, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, and a substituent Examples thereof include an alkenyl group, an aryl group which may have a substituent, and a heteroaryl group which may have a substituent. Specifically, an alkyl group having 1 to 70 carbon atoms (e.g., methyl, ethyl, and the like, any of which is 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); alkenyl groups having 2 to 35 carbon atoms (eg, propenyl, butenyl, pentenyl, hexenyl, heptenyl, heptenyl) , Octenyl, nonenyl, decenyl, undecenyl, dodecenyl); cycloalkyl groups having 3 to 10 carbon atoms (eg, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl); 6 to 32 carbon atoms Aromatic ring group (eg, phenyl, naphthyl, biphenyl, phenanthryl, anthracenyl), heterocyclic group (a residue of a heterocyclic ring containing at least one hetero atom selected from nitrogen atom, oxygen atom, and sulfur atom) For example, pyridyl, pyrimidyl, triazinyl, thienyl, furyl, pyrrolyl, pyrazolyl, imidazolyl, triazolyl, thiazolyl, imidazolyl, oxazolyl, thiadiaryl, oxadiazolyl, quinolyl, isoquinolyl); or a combination thereof. These substituents may have one or more substituents if possible, and examples of the substituent include an alkoxy group, an alkoxycarbonyl group, a halogen atom, an ether group, an alkylcarbonyl group, a cyano Groups, thioether groups, sulfoxide groups, sulfonyl groups, amide groups and the like.

The substituent represented by R ^b is preferably an alkyl group or a substituent having an oxyalkylene structure. Among them, the substituent represented by R ^b is preferably an alkyl group which may have a substituent. The carbon number of R ^b is preferably 1 or more, more preferably 4 or more, still more preferably 5 or more, still more preferably 6 or more, particularly preferably 8 or more. preferable. The carbon number of R ^b is preferably 70 or less, more preferably 48 or less, still more preferably 32 or less, and particularly preferably 24 or less.
The alkyl group represented by R ^b may be linear or branched, but is preferably branched from the viewpoint of lubricity under severe conditions such as high temperature and / or high pressure, and to the base oil When using as an additive, it is preferable also from a soluble viewpoint. Preferably, R ^b does not have a substituent other than the alkyl branched chain.
The branched alkyl group is preferably an alkyl group having one branched alkyl group having 1 to 12 carbon atoms, and more preferably an alkyl group having one branched alkyl group having 1 to 10 carbon atoms. Among them, an alkyl group having 3 to 20 carbon atoms (total carbon number 4 to 32) having one alkyl group having 1 to 12 carbon atoms as a branched chain at 2-position is preferable, and an alkyl group having 1 to 10 carbon atoms as a branched chain The alkyl group having 4 to 14 carbon atoms (having 5 to 24 carbon atoms in total) having one at the 2-position is preferable.

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 more preferably contains an oxyethylene group or an oxypropylene group, and may contain a polyoxyalkylene structure containing two or more oxyalkylene groups repeatedly. The polyoxyalkylene structure preferably contains a polyoxyethylene group or a polyoxypropylene group. When R ^b has an oxyalkylene structure, the number of carbons of R ^b described above is a number including the number of carbons contained in the oxyalkylene structure.

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

In the general formula Ax, the carbon number + m + n of Y is 10 or more. The carbon number of Y + m + n may be 10 or more, but the carbon number of Y, m and n are selected such that the carbon number of the ester compound represented by the general formula Ax is 20 or more. The carbon number + m + n of Y is preferably 12 or more, more preferably 24 or more, and still more 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, still more 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. 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, the carbon number of Y + m + n is 10 or more, L is an alkylene group, m is an integer of 1 or more, n is 1 or more It is an integer, p is an integer greater than or ^equal to 1, Rc 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 carbon number of Y in the general formula Ay is preferably 8 or more, more preferably 10 or more, still more preferably 14 or more, still more preferably 20 or more, and 30 or more. It is further more preferable that it is, and especially preferable that it is 34 or more. Y may have a substituent, and the carbon number of Y as referred to herein means the number including the carbon number of the substituent. Further, 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, and in particular, a dimer acid residue And trimer acid residues or erucic acid dimer residues.

  Preferred ranges of m and n in the general formula Ay are the same as the preferred ranges of m and n in the general formula Ax.

  L in the general formula Ay is an alkylene group. The carbon number of the alkylene group represented by L is preferably 2 to 4, 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, still more preferably an integer of 1 to 10, still more preferably an integer of 1 to 8, and 1 to 4 Particularly preferred is an integer.

As R ^c in the general formula Ay, a substituent represented by R ^b in the general formula Ax can be mentioned. R ^c is an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkenyl group which may have a substituent, an aryl group which may have a substituent or a substituent It is preferable that it is a heteroaryl group which may have, and it is more preferable that it is an alkyl group which may have a substituent. Among them, R ^c is preferably an alkyl group which may have a substituent, and the carbon number thereof is preferably 1 or more, more preferably 4 or more, and 5 or more. More preferably, it is 6 or more, still more preferably 8 or more. The carbon number of the alkyl group which may have a substituent is preferably 32 or less, more preferably 24 or less.
The alkyl group represented by R ^c may be linear or branched, but is preferably branched from the viewpoint of lubricity under severe conditions such as high temperature and / or high pressure, and to the base oil When using as an additive, it is preferable also from a soluble viewpoint.
The branched alkyl group is preferably an alkyl group having one branched alkyl group having 1 to 12 carbon atoms, and more preferably an alkyl group having one branched alkyl group having 1 to 10 carbon atoms. Among them, an alkyl group having 3 to 20 carbon atoms (total carbon number 4 to 32) having one alkyl group having 1 to 12 carbon atoms as a branched chain at 2-position is preferable, and an alkyl group having 1 to 10 carbon atoms as a branched chain More preferred is an alkyl group having 4 to 14 carbon atoms (one having 5 to 24 carbon atoms in total) having one at the 2-position.

Examples of the substituent which 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 However, it is preferable that R ^c be one having no substituent other than alkyl branched chain.

  Although the preferable specific example of the ester compound contained in the lubricant composition of this invention is shown below, the ester compound used by this invention is not limited to this.

As in the ester compounds Aa-1 to Aa-11, when having a substituent R ¹⁰¹ , 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 two or more valences is monoesterified, and is an ester having 20 or more carbon atoms It is preferably a compound. Specifically, when the polyvalent carboxylic acid is a divalent carboxylic acid, it is preferable that only one carboxyl group out of two carboxyl groups is a partial ester compound esterified with 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 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 polyvalent carboxylic acid having two or more valences is esterified with a monool, It is preferable that it is several 20 or more partial ester compound. The carbon number of the divalent or higher polyvalent carboxylic acid used in the present invention is preferably 10 or more, more preferably 12 or more, still more preferably 16 or more, and more preferably 24 or more. More preferably, it is particularly preferably 32 or more, and most preferably 36 or more. Further, 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 polyvalent carboxylic acids having 2 or more valences include carboxylic acid derivatives having 10 or more carbon atoms, and multimers of unsaturated fatty acids. As a carboxylic acid derivative having 10 or more carbon atoms, 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 them, at least one selected from a succinic acid derivative having a substituent having 8 or more carbon atoms and a multimer of unsaturated fatty acid having 16 or more carbon atoms is used as the polyvalent carboxylic acid having 10 or more carbon atoms. Is preferred.
Examples of succinic acid having a substituent having 8 or more carbon atoms include octenyl succinic acid, decenyl succinic acid, tetrapropenyl succinic acid (dodecenyl succinic acid), and alkenyl succinic acids such as octadecenyl succinic acid.
As multimers of unsaturated fatty acids having 16 or more carbon atoms, dimer acids (dimers of unsaturated carboxylic acids having 18 carbon atoms), hydrogenated products of dimer acids, trimer acids (unsaturated carboxylic acids having 18 carbon atoms) (Trimer), dimers of unsaturated carboxylic acid having 22 carbon atoms (eg, erucic acid dimer) and the like can be mentioned. That is, the carbon number of the divalent or higher polyvalent carboxylic acid used in the present invention is particularly preferably 36 or more. Among them, dimer acids, hydrogenated products of dimer acids, trimer acids, and dimers of unsaturated carboxylic acids having 22 carbon atoms are preferably used from the viewpoint of solubility in base oils. Here, a dimer acid is an aliphatic or alicyclic dicarboxylic acid (other than most of dimers) which is formed by dimerization of unsaturated fatty acid (usually, carbon number 18) by polymerization or Diels-Alder reaction etc. Among them, trimers, monomers containing several mol%, etc. are often contained), and among them, those having a trimer as the main component are defined as trimer acids.
As a specific example of a dimer acid or trimer acid, Tsunodaim (trademark) 205, 216, 228, 395 by Tsukino Food Industry Co., Ltd. is mentioned as an example of a dimer acid, Tsunodaim 345 etc. is mentioned as an example of a trimer acid Be As the dimer acid or trimer acid, another product of Cognis, Unichema, or Croda may be used. As an example of the dimer of a C22 unsaturated carboxylic acid, pripol 1004 by Croda, etc. may be mentioned.

<Monoall>
The number of carbon atoms of the monool may be 1 or more, 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, still more preferably 32 or less, and particularly preferably 24 or less. As monools, aliphatic monools are preferable, those having branched alkyl chains are more preferable, and those having branched alkyl chains having 1 to 12 carbon atoms are particularly preferable.

  Examples of monools suitable for the present invention include methanol, ethanol, butanol, isobutanol, pentanol, propanol, hexanol, 2-ethylhexanol, 2-hexyloctanol, 2-octyldecanol, heptanol, octanol, decanol, dodecanol Hexadecanol, 2-heptyl undecanol, eicosadecanol, phytosterol, isostearyl alcohol, stearyl alcohol, cetole, behenol and the like. Moreover, it is preferable that the monool used by this invention further has an oxyalkylene structure. Examples of monools having an oxyalkylene structure include the above-mentioned alkylene oxide adducts of monools.

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

Here, in the general formula (3), R ^a 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, a substituent It is 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. Further, na1 represents an integer of 2 to 4, and na2 represents an integer of 1 to 20. The plurality of X ^a1 may be the same or different, and the plurality of X ^a2 may be the same or different. Also, in the case of na2 it is 2 or more, a plurality of _{^{-O (CX a1 X a2) na1}} - may or may not be the same.

It is preferable that carbon number of the alkyl group part of the alkyl group which may have a substituent represented by R ^a is 1-32, It is more preferable that it is 4-32, It is 5-24 Is more preferred. The alkyl group represented by R ^a may be linear or branched, but is preferably branched from the viewpoint of lubricity under severe conditions such as high temperature and / or high pressure, and to the base oil When using as an additive, it is preferable also from a soluble viewpoint.

It is preferable that carbon number of the alkenyl group part of the alkenyl group which may have a substituent represented by R ^a is 2-32, It is more preferable that it is 4-32, It is 5-24 Is more preferred. The alkenyl group represented by R ^a may be linear, branched or cyclic.

The carbon number of the aryl group portion of the aryl group or heteroaryl group which may be substituted represented by R ^a is preferably 6 to 32, and more preferably 6 to 24. As an aryl group which ^Ra represents, a phenyl group, a naphthyl group, etc. can be mentioned, Among these, a phenyl group is especially preferred. Moreover, as the heteroaryl group represented by R ^a , for example, imidazolyl group, pyridyl group, quinolyl group, furyl group, thienyl group, benzoxazolyl group, indolyl group, benzimidazolyl group, benzthiazolyl group, carbazolyl group, azepinyl group Can be illustrated. The hetero atom contained in the heteroaryl group is preferably an oxygen atom, a sulfur atom or a nitrogen atom.

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

  In general (3), na1 is preferably an integer of 2 to 4, more preferably 2 or 3, and still more preferably 2. Furthermore, na 2 is more preferably an integer of 1 to 20, still 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 which may be possessed by R ^a 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 mentioned, it is preferable that R ^a is ^a thing which does not have a substituent other than the alkyl branched chain.

(Esterification reaction mixture)
In the lubricant composition of the present invention, in addition to the partial ester compound of the polyvalent carboxylic acid in which a part of the carboxyl group of the polyvalent carboxylic acid having 2 or more valences as described above is monoesterified, It may be a complete ester compound of a carboxylic acid and 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 of the carboxyl groups in one molecule of polyvalent carboxylic acid having two or more valences 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 polyvalent carboxylic acid molecule are not esterified. That is, the lubricant composition of the present invention may contain a mixture of a partial ester compound of polyvalent carboxylic acid and a full polyvalent carboxylic acid ester compound, and the partial ester compound of polyvalent carboxylic acid and polyvalent carboxylic acid complete A mixture of an ester compound and a polyvalent carboxylic acid may be included.

  A mixture of a partial ester compound of polyvalent carboxylic acid and a polyvalent carboxylic acid complete ester compound and / or a polyvalent carboxylic acid comprises an isolated partial ester compound and an isolated complete ester compound and / or polyvalent carboxylic acid Although it may be a mixed mixture, it may be an esterification reaction mixture of a polyvalent carboxylic acid having two or more valences and a monool. Specifically, polyvalent carboxylic acid and monool having the same reactivity are reacted with each other to produce polyvalent ester in which all carboxyl groups in one polyvalent carboxylic acid molecule are esterified with monool in addition to the partial ester compound. A mixture of a carboxylic acid complete ester compound and a raw material polyvalent carboxylic acid remaining without being esterified can be obtained. For example, when a monohydric acid is reacted with a divalent carboxylic acid such as adipic acid, sebacic acid, dimer acid, etc., in addition to the monoester compound having one carboxyl group and one ester bond, the raw material polyvalent carboxylic acid and An esterification reaction mixture is obtained in which a complete ester compound in which all carboxyl groups in one carboxylic acid molecule are esterified is mixed. 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%. And 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 carboxyl groups of all carboxyl groups in all molecules of polyvalent carboxylic acid having 2 or more valences be esterified with monool, and 55 to 85% It is more preferable that the carboxyl group of the above be esterified by monool, and it is further preferable that 60 to 80% of the carboxyl group is esterified by 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, a 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 formula (Cy) is included. In such a case, the ratio of the number of ester bonds in all the molecules of the esterification reaction mixture can be calculated by ¹ H-NMR integral value (Hb / Ha) × 100. In the following formulas (Cx) and (Cy), Rx is the remaining group obtained by removing one (COOHCH _2- ) group from the polyvalent carboxylic acid or partial ester compound. In the following formula (Cy), Ry is a remaining group formed by removing mono-ol (-CH ₂ OH) groups. Ha and Hb each independently represent a hydrogen atom.

  The esterification reaction mixture is preferably obtained by charging a polybasic carboxylic acid and a monool at a carboxyl group / hydroxyl group molar ratio of 1 / 0.5 to 1 / 0.95 and causing an esterification reaction.

  The polyvalent carboxylic acid having two or more valences may be a polyvalent carboxylic acid derivative having two or more valences, and when using an acid anhydride as the polyvalent carboxylic acid derivative, a monoester by reacting with one equivalent of monool. A compound (partial ester compound) can be obtained. For example, an alkenyl succinic monoester can be obtained by reacting a monool with one equivalent of the aforementioned alkenyl succinic anhydride. The monoester compound obtained when using the acid anhydride is not mixed with the polyvalent carboxylic acid complete ester compound or the polyvalent carboxylic acid, and in the present invention, only such monoester compound is subjected to esterification reaction It can also be used as a mixture. In addition, 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 one equivalent of monool. .

(Components other than ester compound of lubricant composition)
The present invention relates to a lubricant composition containing at least the above-mentioned ester compound having 20 or more carbon atoms. Various additives and / or media can be added to the lubricant composition of the present invention in addition to the above-mentioned ester compound having 20 or more carbon atoms.

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

(Medium)
As the medium (also referred to as base oil), mineral oil, oil and fat compound, polyolefin oil (eg, polyalphaolefin), silicone oil, ether oil (eg, perfluoropolyether oil, diphenyl ether derivative), ester oil (eg, aromatic ester oil, One or two or more selected from monovalent fatty acid esters, divalent fatty acid diesters, polyol ester lubricating oils) can be mentioned. Among them, the medium is preferably at least one selected from mineral oil, polyolefin oil and ester oil.

In the present invention, "medium" refers to all media generally referred to as "flowable liquid". However, it is not necessary to be liquid at room temperature or at the temperature used, and any form of material such as solid and gel can be used besides liquid. The medium used in the present invention is not particularly limited, and can be selected from various liquids depending on the application. As for the medium that can be used in the present invention, the description in paragraphs 0067 to 0096 of JP-A-2011-89106 can be referred to. Kinematic viscosity at 40 ° C. of the medium is preferably from 1 to 500 mm ² / s, more preferably 1.5~200mm ² / s, more preferably 2 to 50 mm ² / s.

    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, the viscosity-temperature characteristics, the thermal / oxidative stability, the volatility preventing property are improved, and the antiwear property is improved. In addition, the viscosity index as used in the field of this invention means the viscosity index measured based on JISK2283-1993.

(Ester compounds and other components other than medium)
Preferred compounds as components other than ester compounds and media, that is, preferred additives to the lubricant composition of the present invention are compounds 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, antioxidants and the like. 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 in which zinc, molybdenum, sulfur and phosphorus are contained alone (oxidation number 0), ions, complexes and the like. Such compounds include organic molybdenum compounds, inorganic molybdenum compounds, organic zinc compounds, (sub) phosphorous acid derivatives, organic sulfur compounds and the like. Among them, organic molybdenum compounds and organic zinc compounds are preferable.

    In addition, as a compound containing at least one selected from zinc, molybdenum, sulfur and phosphorus as a constituent element, only one type may be added to the lubricant composition of the present invention, and two or more types of the lubricant of the present invention It may be added to the composition. When two or more compounds containing at least one element selected from zinc, molybdenum, sulfur and phosphorus are combined and added 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 the (sub) phosphoric acid derivative and the organic sulfur compound, and it is more preferable to combine the organic molybdenum compound and the organic zinc compound.

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

As an organic molybdenum compound used as an additive in a lubricant composition, an organic molybdenum compound containing phosphorus such as molybdenum dithiophosphate (sometimes referred to as MoDTP) can be mentioned. Other organomolybdenum compounds can include sulfur containing organomolybdenum compounds such as molybdenum dithiocarbamate (sometimes referred to as MoDTC). As the organic molybdenum compound containing sulfur, for example, sulfurized oxymolybdenum-N, N-di-octyldithiocarbamate (C ₈ -Mo (DTC)), sulfurized oxymolybdenum N, N-di-tridecyldithiocarbamate ( C ₁₆ -Mo (DTC)), etc. are preferable.

Examples of other sulfur-containing organic molybdenum compounds include complexes of inorganic molybdenum compounds and sulfur-containing organic compounds. As an inorganic molybdenum compound used for the organic molybdenum compound which is a complex of an inorganic molybdenum compound and a sulfur-containing organic compound, for example, molybdenum dioxide such as molybdenum dioxide or molybdenum trioxide, orthomolybdic acid, paramolybdic acid, (poly) sulfurization Molybdic acids such as molybdic acid, metal salts of these molybdic acids, molybdates such as ammonium salts, molybdenum disulfides, molybdenum trisulfides, molybdenum pentasulfides, molybdenum sulfides such as poly molybdenum sulfides, sulfurized molybdenum acids, sulfurized molybdic acids Metal salts or amine salts, molybdenum halides such as molybdenum chloride, and the like can be mentioned. Moreover, as a sulfur containing organic compound used for the organic molybdenum compound which is a complex of an inorganic molybdenum compound and a sulfur containing organic compound, for example, alkyl (thio) xanthate, thiadiazole, mercapto thiadiazole, thiocarbonate, tetrahydrocarbyl thiuram disulfide And bis (di (thio) hydrocarbyl dithiophosphonate) disulfide, organic (poly) sulfide, sulfurized ester and the like.
Examples of other sulfur-containing organic molybdenum compounds include complexes of sulfur-containing molybdenum compounds such as molybdenum sulfide and sulfurized molybdic acid with alkenyl succinimide.

    As the organic molybdenum compound, an organic molybdenum compound which does not contain phosphorus or sulfur as a constituent element can be used. Specific examples of organic molybdenum compounds not containing phosphorus or sulfur as constituent elements include molybdenum-amine complexes, molybdenum-succinimide complexes, molybdenum salts of organic acids, molybdenum salts of alcohols, and the like, among which molybdenum 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 mentioned as an example of the inorganic molybdenum compound used for the organic molybdenum compound which is a complex of the inorganic molybdenum compound and the sulfur-containing organic compound.

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

In the above formulas, Q ¹ , Q ² , Q ³ and Q ⁴ may be the same or different, and each independently an isopropyl group, a butyl group, an isobutyl group, a pentyl group, an isopentyl group, a neopentyl group, a hexyl group, a heptyl group And an alkyl group having 8 to 20 carbon atoms such as octyl group, 2-ethylhexyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, mistyl 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-ethylhexyl dithiophosphate (C ₈ ZnDTP) Or zinc isopropyl-1-ethylbutyl dithiophosphate (C ₃ / C ₆ ZnDTP).

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. It is more preferable that 1000 mg / L is contained, and it is further preferable that 100 to 800 mg / L is contained.
When an organozinc compound is used, the organozinc compound is preferably contained in an amount of 50 to 10000 mg / L as a zinc content, and 100 to 5000 mg / L based on the total mass of the lubricant composition. Is more preferable, and 200 to 1500 mg / L is more preferable.
By setting the content of the organic metal compound such as the organic molybdenum compound or the organic zinc compound in the lubricant composition in the above range, the stability of the lubricant composition can be enhanced, and severe conditions such as high temperature and / or high pressure The lubricating properties under the conditions can be improved, and furthermore, the wear suppressing ability can be exhibited.

  As the (sub) phosphate derivatives, in addition to the above-mentioned zinc dithiophosphate (ZDTP) and zinc diphosphate (ZDP), phosphite esters, phosphate esters, aromatic phosphate esters such as tricresyl phosphate, phosphorus Aliphatic phosphoric acid esters such as acid trialkyl can be illustrated as a preferred example. Among them, aromatic phosphates such as tricresyl phosphate and aliphatic phosphates 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 compounds, for example, a viscosity index improver (preferably polyalkyl (meth) acrylate, alkyl (meth) acrylate-(meth) acrylate co-polymer having polar group) (Copolymers, polymers and copolymers of butadiene, olefins or alkylated styrenes), antioxidants (preferably hindered phenolic compounds, sulfurized alkylphenol compounds, aromatic amine compounds, low sulfur peroxide decomposers, oil soluble copper compounds), cleaning Agents (sulfates, phenates, alkali metal salts or alkaline earth metal salts of phosphates and salicylates, (borate-modified) succinimides, succinates), dispersants (preferably phenates, sulfonates, sulfated phenates, salicylates) , Naf Salts, 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 wax and aromatic compounds, vinyl carboxylate polymers and terpolymers of dialkyl fumarates, fatty acid vinyl esters and allyl vinyl ethers), Corrosion inhibitors (preferably thiadiazole), seal compatible agents (preferably organic phosphates, aromatic esters, aromatic hydrocarbons, esters (eg butyl benzyl phthalate) and polybutenyls 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, it is possible to obtain a lubricant composition capable of exhibiting a function such as wear suppression. About the additive which can be used in this invention, the description of Unexamined-Japanese-Patent No.2011-89106, Paragraph 0098-0165 can be referred to.

(Properties of Lubricant Composition)
The lubricant composition of the present invention preferably has a kinematic viscosity at 40 ° C. of 500 mm ² / s or less, more preferably 200 mm ² / s or less, still more preferably 100 mm ² / s or less , particularly preferably not more than 50 mm ² / s, and most preferably from 5 to 50 mm ² / s. The viscosity needs to be adjusted because an appropriate viscosity is required depending on the use environment. In the present 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 a grease to prepare a grease composition. In such an embodiment, in order to ensure practical performance when adapted to the use of the grease, if necessary, a thickener or the like can be appropriately added within the range that does not impair the object of the present invention. When adding a thickener, it is preferable to contain 10-50 mass% of thickeners with respect to the total mass of a grease composition. Hereinafter, additives which can be added when preparing the grease composition will be described.

  As thickeners that can be added, non-soap-based increase in soap-based thickeners such as metal soaps and complex metal soaps, benton, silica gel, urea-based thickeners (urea compounds, urea-urethane compounds, urethane compounds, etc.) Any thickening agent, such as a thickening agent, can be used. Among these, soap-based thickeners and urea-based thickeners are preferably used because they are less likely to damage the resin-made members.

  Examples of the soap-based thickeners include sodium soap, calcium soap, aluminum soap, lithium soap and the like, and among these, lithium soap is preferable in terms of water resistance and heat stability. Examples of the lithium soap include lithium stearate and lithium-12-hydroxystearate.

  Moreover, as a urea system thickener, a urea compound, a urea urethane compound, a urethane compound, or these mixtures etc. are mentioned, for example.

  As a urea compound, a urea urethane compound and a urethane compound, for example, a diurea compound, a triurea compound, a tetraurea compound, a polyurea compound (except for a diurea compound, a triurea compound and a tetraurea compound), a urea urethane compound, a diurethane compound or a mixture thereof Etc. Preferably, a diurea compound, a urea urethane compound, a diurethane compound or a mixture thereof is mentioned.

  The grease composition can also contain a solid lubricant as an additive. As a solid lubricant, for example, polytetrafluoroethylene, boron nitride, fullerene, graphite, fluorinated graphite, melamine cyanurate, molybdenum disulfide, Mo (molybdenum) -dithiocarbamate, antimony sulfide, alkali (earth) metal boric acid Salt etc. are mentioned.

  The grease composition can also contain a wax as an additive. Examples of the wax include natural waxes and various waxes of mineral oil type or synthetic type. Specifically, montan wax, carnauba wax, amide compound of higher fatty acid, paraffin wax, microcrystalline wax, polyethylene wax, polyolefin wax And ester wax.

  In addition, as a metal deactivator, benzotriazole, benzimidazole, thiadiazole and the like are known, 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) acrylates are also known to be effective in preventing cold noise in cold regions.

(Method of producing lubricant composition)
The present invention is a method for producing a lubricant composition, which comprises the step of esterifying a part of carboxyl groups of a polyvalent carboxylic acid with a monool, which comprises at least one ester bond and one carboxyl group 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 step of esterification, an esterification reaction mixture is preferably produced.

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

  The method for producing a lubricant composition comprises, after the step of esterification, a step of isolating only an ester compound having 20 or more carbon atoms which contains at least one ester bond and at least one carboxyl group in one molecule. May be included. In the step of isolation, the esterification reaction mixture is preferably purified by column chromatography.

(Step of esterifying)
The step of esterifying includes the step of dehydration condensation of the above-described divalent or higher polyvalent carboxylic acid and monool. In the present invention, such dehydration condensation reaction is not adjusted to all carboxyl groups of polyvalent carboxylic acid, but is adjusted to reaction conditions to occur to some carboxyl groups. For example, in the step of esterification, it is preferable to charge the polyvalent carboxylic acid and monool at a molar ratio of carboxyl group / hydroxyl group of 1 / 0.5 to 1 / 0.95 to cause an esterification reaction. Further, the esterification reaction conditions may be adjusted so that the polybasic carboxylic acid and the monool are charged at 1/1 to 1/10 in the molar ratio of carboxyl group / hydroxyl group to form a partial ester compound. When monool remains after the reaction, the monool is preferably removed by a method such as distillation under reduced pressure.

  The dehydration condensation reaction is preferably carried out in the presence or absence of a catalyst. Further, in dehydration condensation, it is desirable to heat or to make a proper amount of a solvent azeotropically with water. Dehydration also proceeds smoothly without coloring of the esterification reaction mixture. The solvent is preferably a hydrocarbon solvent having a boiling point of 100 to 200 ° C, more preferably a hydrocarbon solvent at 100 to 170 ° C, and most preferably a hydrocarbon solvent at 110 to 160 ° C. Examples of these solvents include toluene, xylene, mesitylene and the like. The amount of the solvent added is preferably 1 to 25% by mass, more preferably 2 to 20% by mass, particularly preferably 3 to 15% by mass, even more preferably 5 to 12% by mass, based on the total amount of polyvalent carboxylic acid and monool. preferable.

  Although the use of a catalyst accelerates the reaction, it is desirable not to use it because post-treatment for removing the catalyst is complicated and causes coloration of the esterification reaction mixture. However, when used, conventional conditions and procedures are used with conventional catalysts. In this regard, reference can be made to JP-A-2001-501989, JP-A-2001-500549, JP-A-2001-507334, and JP-A-2002-509563.

  After completion of the charging, the reaction is carried out 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, the solvent containing water is azeotroped, cooled at a cooling site such as Dean Stark, and separated into water and solvent by becoming liquid. This water should 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, for example, be supplied 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 material of the sliding surface include alloy steels for structural machines such as carbon steel for machine structure, nickel chromium steel, nickel chromium molybdenum steel, chromium steel, chromium molybdenum steel and aluminum chromium molybdenum steel, stainless steel, Multi-aging steel etc. are mentioned.

As the material of the sliding surface, various metals other than steel, or inorganic or organic materials other than metal are also widely used. Examples of inorganic or organic materials other than metals include various plastics, ceramics, carbon, etc., and mixtures thereof. More specifically, metal materials other than steel include cast iron, copper-copper-lead-aluminum alloy, castings thereof and white metal.
As for the material of the sliding surface, the description in paragraphs [0168] to [0175] of JP-A-2011-89106 can be referred to.

    The lubricant composition of the present invention can be used in various applications. For example, lubricating oil for grease, mold release agent, oil for internal combustion engine, engine oil for internal combustion engine, oil for metal processing (cutting), oil for bearing, fuel for combustion engine, vehicle engine oil, gear oil, operation for automobile Oil, lubricating oil for ships and aircraft, machine oil, turbine oil, oil for bearings, hydraulic oil, compressor / vacuum pump oil, refrigerator oil, lubricating oil for metal processing, lubricant for magnetic recording media, lubricant for micro machine It can be used as an artificial bone lubricant, a shock absorber oil or a rolling oil. In addition, it is also used in air conditioners and refrigerators with reciprocating and rotary hermetic compressors, automotive air conditioners and dehumidifiers, freezers, freezers, freezers, refrigerators, vending machines, showcases, chemical plants, etc. .

The lubricant composition of the present invention can also be used as a lubricant for metal processing that does not contain a chlorine compound. For example, when a steel material or a metal material such as Al (aluminum) alloy is hot-rolled or processed such as cutting, cold rolling oil of aluminum, cutting oil, grinding oil, drawing oil, press The lubricant composition of the present invention can be used as metal processing oil such as processing oil or plastic processing oil of metal. The lubricant composition according to the present invention is a metalworking oil composition which is particularly applicable as an inhibitor for high speed, high load machining wear, breakage, surface roughening and for low speed heavy cutting such as broaching and gun drilling. It is also useful.
Further, the lubricant composition of the present invention can be used for various grease lubricants, lubricants for magnetic recording media, lubricants for micromachines, lubricants for artificial bones, 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, and solubilizing agent. A high-performance lubricating oil that is completely harmless to the human body is obtained by using an edible oil such as sorbitan fatty acid ester containing polyoxyethylene ether, which is widely used in cake mixes, salad dressings, shortening oils, chocolates, etc. Can. Such lubricating oils can be used for manufacturing equipment of medical food production lines and medical equipment members.
Furthermore, the lubricant composition of the present invention can be used as a cutting oil or a rolling oil by emulsifying and dispersing in a water system or dispersing in a polar solvent or a resin medium.

The lubricant composition of the present invention can also be used as a mold release agent for various uses. For example, polycarbonate resin, flame retardant polycarbonate resin, crystalline polyester resin which is a main component of an image forming toner used in an electrophotographic apparatus, electrostatic recording apparatus, etc., various molding thermoplastic resin compositions, and semiconductor sealing It is used as a release agent for epoxy resin compositions and the like.
Moreover, it can be used also as an antifouling agent which promotes detachment | leave of the stain | pollution | contamination adhering to textiles and it prevents the stain | pollution | contamination of textiles by kneading in textile products, such as clothing, beforehand, and applying.

The features of the present invention will be more specifically described below with reference to examples and comparative examples. The materials, amounts used, proportions, treatment contents, treatment procedures, etc. 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 should not be construed as limited by the specific examples shown below. In the following, Examples 1 to 5, 9, 11, 13 and 14 will be read as Reference Examples 1 to 5, 9, 11, 13 and 14, respectively.

(Synthesis of Ester Compound Aa-1)
One equivalent of 2-ethylhexanol was added dropwise over 30 minutes to octenyl succinic anhydride (Rikasid OSA, manufactured by Shin Nippon Rika Co., Ltd.), reacted at room temperature for 1 hour, and then reacted at 50 ° C. for another 3 hours. The reaction was carried out without solvent. The product was purified by column chromatography to obtain partially ester compound Aa-1. In addition, although the partial ester compound with high purity is obtained also under the said conditions reaction conditions, it becomes possible to refine | purify only a partial ester compound by refine | purifying with column chromatography.

(Synthesis of Ester Compound Aa-2)
Partial ester compound Aa-2 was obtained using the same method as ester compound Aa-1 except having used 2- (2-ethylhexyl oxy) ethanol instead of 2-ethyl hexanol.

(Synthesis of Ester Compound Aa-4)
Partial ester compound Aa-4 was obtained using the same method as ester compound Aa-1 except having used dodecenyl succinic anhydride (Rikashid DDASA by Nippon Nippon Chemical Co., Ltd.) instead of octenyl succinic anhydride.

(Synthesis of Ester Compound Aa-6)
An ester compound Aa-except using dodecenyl succinic anhydride (Rikasid DDAS, manufactured by Nippon Nippon Chemical Co., Ltd.) in place of octenyl succinic anhydride and 2-((2-ethylhexyl) oxyethoxy) ethanol in place of 2-ethylhexanol Partial ester compound Aa-6 was obtained using the same method as 1.

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

(Synthesis of Ester Compound Ab-2)
Partial ester compound Ab-2 was obtained using the same method as ester compound Ab-1 except having used 2- (2-ethylhexyl oxy) ethanol instead of 2-ethyl hexanol.

(Synthesis of Ester Compound Ab-3)
Partial ester compound Ab-3 was obtained using the same method as ester compound Ab-1 except having used 2-((2-ethylhexyl) oxyethoxy) ethanol instead of 2-ethyl hexanol.

(Synthesis of Ester Compound Ab-11)
Partial ester compound Ab-11 was obtained using the same method as ester compound Ab-1 except having used polyethyleneglycol monoisostearyl ether (average oxyethylene group number 6) 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 having used sebacic acid instead of the dimer acid.

(Synthesis of Ester Compound Ad-3)
Partial ester compound Ad-3 was obtained using the same method as ester compound Ab-3 except having used the erucic acid dimer (Kurida company make, Pripol 1004) instead of the dimer acid.

As a comparison compound, an ester compound having no carboxyl group or an ester compound having less than 20 carbon atoms was used.
(Ester Compound X1) Octenyl Succinic Acid Bis (2-ethylhexyl)
(Ester Compound X2) Octenyl Succinic Acid Bis (2- (ethylhexyloxy) ethyl)
(Ester Compound X3) Dimer Acid Bis (2- (2-ethylhexyloxy) ethyl)
(Ester Compound X4) Sebacic Acid Bis (2- (2-ethylhexyloxy) ethyl)
(Ester Compound X5) Sebacic Acid Mono (2-ethylhexyl) Carbon Number 18

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

(Evaluation)
(Coefficient of friction)
The friction coefficient of each of the lubricant compositions of the examples and comparative examples was measured using a vibrating friction and wear tester (SRV 4 manufactured by Optimol Instruments Prueftechnik GmbH). In the measurement of the coefficient of friction, at a temperature of 40 ° C., a frequency of 50 Hz, a load of 150 N, an amplitude of 2 mm (condition 1) and at a temperature of 80 ° C., a frequency of 50 Hz, a load of 300 N, an amplitude of 2 mm (condition 2) The friction and wear test was carried out for 1 hour under each of the conditions of 1) and the coefficient of friction at 30 minutes was measured. A 10 mm SUJ-2 ball and a lower test specimen 24 mm SUJ-2 disc were used as the upper test piece of the friction and 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 with the coefficient of friction of condition 2 of Comparative Example 1 as 100%, and evaluated as follows. The smaller the value, the smaller the coefficient of friction, and the better the lubricating property. The coefficients of friction of a, b and c were greatly reduced, and it was judged that the improvement effect was large. In the tests of conditions 1 and 2, the evaluation of c or more was taken as the 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 (base)

Mineral oil: JX Nippon Oil Corporation Super Oil N 46 (40 ° C dynamic viscosity 46 mm ² / s)
PAO (poly-α-olefin oil): Anderol FG C 46 (40 ° C. dynamic viscosity 46 mm ² / s) manufactured by Anderol

  As shown in Table 1, in the lubricant composition obtained in the examples, it is understood that the friction coefficient is small under any of the conditions 1 and 2, and good lubricating performance can be exhibited. On the other hand, in the lubricant composition obtained in the comparative example, it can be seen that the friction coefficient is large and the lubricating characteristics are inferior.

  Furthermore, a mixture containing an ester compound and a complete ester compound in which all of the carboxylic acids were esterified was obtained by the following method.

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

(Preparation of mixture Ab-2 m2)
0.6 equivalents of 2- (2-ethylhexyloxy) ethanol was mixed with respect to the amount of carboxylic acid of dimer acid (manufactured by Tsukino Foods Co., Ltd., Tsunodime 395), and reaction was performed at 220 ° C. for 5 hours under nitrogen stream. The remaining 2- (2-ethylhexyloxy) ethanol was removed by evaporation under reduced pressure to obtain a mixture Ab-2m2 containing an ester compound Ab-2. As confirmed by NMR, Ab-2m2 was esterified on average 52% of the carboxylic acid.

(Preparation of mixture Ab-2m3)
0.75 equivalent of 2- (2-ethylhexyloxy) ethanol was mixed with respect to the amount of carboxylic acids of dimer acid (Tunodime 395, manufactured by Tsukino Foods Co., Ltd.), and reacted at 220 ° C. for 5 hours under nitrogen stream. The remaining 2- (2-ethylhexyloxy) ethanol was removed by evaporation under reduced pressure to obtain a mixture Ab-2m3 containing the ester compound Ab-2. As confirmed by NMR, Ab-2m3 was esterified on average 65% of the carboxylic acid.

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

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

(Examples 21 to 25)
A lubricant composition was prepared by mixing a mixture containing a complete ester compound in which all of the carboxylic acids were esterified in addition to the ester compound in the amount as shown in Table 2 to the base oil. The coefficient of friction was evaluated using the same method as in Example 1 for this.

  As shown in Table 2, even in the case of using a mixture containing a complete ester compound in which all carboxylic acids are esterified in addition to the ester compound, the coefficient of friction is reduced and good. It turned out that it exhibits lubricating characteristics.

(Examples 31 and 32)
Lubricant composition using a base oil obtained by adding a molybdenum dithiocarbamate (MoDTC) at a Mo concentration of 800 mg / L and a zinc dithiophosphate (ZnDTP) at a Zn concentration of 800 mg / L to Super Oil N46 manufactured by JX Nippon Oil Corporation as a base oil. Prepared. The coefficient of friction was evaluated using the same method as in Example 1 for this.

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

Grease 1: Mobil SHC Grease 460WT

  As shown in Table 4, the grease compositions obtained in the examples have good frictional properties.

Claims (5)

Lubricant composition containing, in one molecule, an ester compound having 20 or more carbon atoms and containing at least one ester bond and at least one carboxyl group, and at least one selected from mineral oil, poly α-olefin oil and grease The object,
The ester compound having 20 or more carbon atoms is a compound represented by the following general formula Ay,
A lubricant composition wherein the content of the ester compound in the lubricant composition is 0.1 to 2.0% by mass ;
In the general formula Ay, Y represents an m + n valent linking group, Y has at least 34 carbon atoms, L is an alkylene group, m is 1, n is 1 and p is an integer of 1 or more R ^c represents a monovalent substituent having 4 or more carbon atoms. A complete ester compound of a polycarboxylic acid, a lubricant composition according to claim 1, carbon atoms further containing 20 or more complete ester compound. Zinc, molybdenum, lubricant composition according to claim 1 or 2 further comprising a compound containing as a constituent element at least one selected from oxygen, sulfur and phosphorus. A method for producing a lubricant composition comprising the step of esterifying a part of carboxyl groups of a polyvalent carboxylic acid with a monool, which is a carbon containing at least one ester bond and at least one carboxyl group in one molecule. And 20 or more ester compounds, and at least one selected from mineral oil, poly α-olefin oil and grease,
The ester compound having 20 or more carbon atoms is a compound represented by the following general formula Ay,
A method for producing a lubricant composition, wherein the content of the ester compound in the lubricant composition is 0.1 to 2.0% by mass.
In the general formula Ay, Y represents an m + n valent linking group, Y has at least 34 carbon atoms, L is an alkylene group, m is 1, n is 1 and p is an integer of 1 or more R ^c represents a monovalent substituent having 4 or more carbon atoms. The method for producing a lubricant composition according to claim 4 , wherein the step of esterifying is a step of esterifying 40 to 95% of carboxyl groups of all carboxyl groups in all polyvalent carboxylic acid molecules with monool. .