JP6033138B2 - Composite polyester composition and lubricant - Google Patents

Description

  The present invention relates to a composite polyester composition and a lubricant. Specifically, the present invention relates to a composite polyester composition containing a specific polyester and a lubricant containing the composite polyester composition.

  Lubricants generally include base oils 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 performance, biodegradability, and the like.

  As ester oil, monoester obtained from reaction of aliphatic monocarboxylic acid and monohydric alcohol; diester obtained from reaction of aliphatic dibasic acid and monohydric alcohol; polyhydric alcohol and aliphatic carboxylic acid; Various esters are disclosed (Patent Documents 1 to 5), such as esters obtained from the above reaction; and complex esters obtained from reaction with polyols, polybasic acids, and aliphatic monocarboxylic acids.

  Patent Document 6 discloses a dimer hydride, a saturated aliphatic alcohol having 1 to 50 carbon atoms, a 2 to 6-valent polyol, a saturated aliphatic carboxylic acid having 2 to 36 carbon atoms, a hydrogenated dimer diol, and A synthetic lubricating oil containing a polycondensate composed of one or more compounds selected from saturated aliphatic dibasic acids having 2 to 36 carbon atoms is disclosed. Further, Patent Document 7 discloses an oil-soluble polyester obtained by polycondensation of at least one selected from a divalent higher carboxylic acid component, a divalent alcohol component, a trivalent or higher carboxylic acid, and a trivalent or higher alcohol. Is disclosed.

JP 2002-097482 A JP 2005-154726 A JP 2005-232434 A JP 2005-213377 A JP 2005-232470 A JP 2002-241777 A JP-A-8-277323

In recent years, with the diversification and sophistication of industrial fields, lubricants are required to have high lubrication performance. For this reason, development of the polyester composition which has low friction property and was excellent in lubrication performance is calculated | required. Furthermore, as the use conditions of the lubricant become severe, there is a demand for a polyester composition that can exhibit excellent lubricating performance even under severe conditions.
However, it has been clarified by the present inventors that a lubricant containing a conventional polyester composition cannot sufficiently exhibit the required lubricating performance. In particular, sufficient lubrication performance cannot be exhibited under severe conditions such as extreme pressure conditions, and further improvements have been demanded.

  Accordingly, the present inventors provide a lubricant having excellent lubricating performance and capable of exhibiting excellent lubricating performance even under extreme pressure conditions in order to solve such problems of the conventional technology. We proceeded with the study for the purpose of doing this.

As a result of intensive studies to solve the above problems, the present inventors have found that lubricating performance can be improved by obtaining a composite polyester composition containing a specific polyester. The specific polyester is a polyester obtained by condensing a polyvalent carboxylic acid containing at least two carboxyl groups, a dimer diol, and a monocarboxylic acid.
Furthermore, the present inventors have found that a composite polyester composition containing such a polyester can exhibit excellent lubricating performance not only under normal conditions but also under extreme pressure conditions, leading to the completion of the present invention. It was.
Specifically, the present invention has the following configuration.

（一般式（１）中、Ｒは炭素数が（１８−ｎ）以下のｎ価の原子団を表し、Ｒ¹は前記ダイマージオールの残基を表し、Ｒ²は置換基を有してもよいアルキル基、置換基を有してもよいシクロアルキル基、置換基を有してもよいアルケニル基、置換基を有してもよいアリール基、置換基を有してもよいヘテロアリール基を表す。なお、ｎは２〜４の整数を表す。）
［４］前記一般式（１）において、ｎは３または４の整数であることを特徴とする［３］に記載の複合ポリエステル組成物。
［５］前記一般式（１）において、Ｒの炭素数は、２以上であることを特徴とする［３］又は［４］に記載の複合ポリエステル組成物。
［６］前記一般式（１）において、Ｒは、置換基を有してもよい飽和脂肪族炭化水素からなる原子団であることを特徴とする［３］〜［５］のいずれかに記載の複合ポリエステル組成物。
［７］前記一般式（１）において、Ｒ²の炭素数は、２以上であることを特徴とする［３］〜［６］のいずれかに記載の複合ポリエステル組成物。
［８］前記一般式（１）において、Ｒ²は、分岐アルキル基又鎖中にエーテル結合を含むアルキル基であることを特徴とする［３］〜［７］のいずれかに記載の複合ポリエステル組成物。
［９］４０℃における粘度が５０〜１６５０ｍＰａｓであることを特徴とする［１］〜［８］のいずれかに記載の複合ポリエステル組成物。
［１０］［１］〜［９］のいずれかに記載の複合ポリエステル組成物と、摩耗防止剤、粘度指数向上剤、酸化防止剤、清浄剤、分散剤，流動、硬化剤、腐食防止剤、シール適合剤、消泡剤、錆防止剤、腐食防止剤、摩擦調整剤、及び増ちょう剤から選択される１種又は２種以上の添加剤とを含有する組成物。
［１１］［１］〜［９］のいずれかに記載の複合ポリエステル組成物、又は［１０］に記載の組成物と、鉱物油、油脂化合物、ポリオレフィン油、シリコーン油、パーフルオロポリエーテル油、芳香族エステル油、及びポリオールエステル潤滑油から選択される１種又は２種以上の媒体とを少なくとも含有することを特徴とする組成物。
［１２］［１］〜［９］のいずれかに記載の複合ポリエステル組成物、又は［１０］又は［１１］に記載の組成物を含むことを特徴とする潤滑剤。
［１３］グリース用潤滑油、離型剤、内燃機関用エンジンオイル、金属加工用（切削用）オイル、軸受け用オイル、燃焼機関用燃料、車両エンジン油、ギヤ油、自動車用作動油、船舶・航空機用潤滑油、マシン油，タービン油、軸受用オイル、油圧作動油、圧縮機・真空ポンプ油、冷凍機油、金属加工用潤滑油剤、磁気記録媒体用潤滑剤、マイクロマシン用潤滑剤、人工骨用潤滑剤、ショックアブソーバ油又は圧延油として用いられることを特徴とする［１２］に記載の潤滑剤。
［１４］少なくとも２つのカルボキシル基を含む多価カルボン酸と、ダイマージオールと、モノカルボン酸とを混合し混合物を得る工程と、前記混合物を脱水縮合する工程を含み、前記多価カルボン酸の炭素数が１８以下であることを特徴とする複合ポリエステル組成物の製造方法。
［１５］前記混合物を得る工程は、前記多価カルボン酸に対して、前記ダイマージオールを混合する当量比が１〜３となり、前記モノカルボン酸を混合する当量比が０．５〜３となるように混合する工程であることを特徴とする［１４］に記載の複合ポリエステル組成物の製造方法。
［１６］前記脱水縮合する工程は、前記混合物に対して１〜２５質量％の、沸点１１０〜１６０℃の炭化水素系溶剤を添加し、水を共沸させつつ、脱水縮合を進行させる工程を含むことを特徴とする［１４］または［１５］に記載の複合ポリエステル組成物の製造方法。 [1] A polyester obtained by condensing a polyvalent carboxylic acid containing at least two carboxyl groups, a dimer diol, and a monocarboxylic acid, wherein the polyvalent carboxylic acid has 18 or less carbon atoms. A featured composite polyester composition.
[2] The composite polyester composition according to [1], wherein the polyvalent carboxylic acid contains three or more carboxyl groups.
[3] The composite polyester composition according to [1], wherein at least one of the polyesters is represented by the following general formula (1).

(In General Formula (1), R represents an n-valent atomic group having (18-n) or less carbon atoms, R ¹ represents a residue of the dimer diol, and R ² has a substituent. A good alkyl group, a cycloalkyl group which may have a substituent, an alkenyl group which may have a substituent, an aryl group which may have a substituent, and a heteroaryl group which may have a substituent. N represents an integer of 2 to 4.)
[4] The composite polyester composition as described in [3], wherein in the general formula (1), n is an integer of 3 or 4.
[5] The composite polyester composition as described in [3] or [4], wherein in the general formula (1), R has 2 or more carbon atoms.
[6] In any one of [3] to [5], in the general formula (1), R is an atomic group composed of a saturated aliphatic hydrocarbon which may have a substituent. Composite polyester composition.
[7] The composite polyester composition according to any one of [3] to [6], wherein in the general formula (1), R ² has 2 or more carbon atoms.
[8] The composite polyester according to any one of [3] to [7], wherein in the general formula (1), R ² is a branched alkyl group or an alkyl group containing an ether bond in the chain. Composition.
[9] The composite polyester composition according to any one of [1] to [8], wherein the viscosity at 40 ° C. is 50 to 1650 mPas.
[10] The composite polyester composition according to any one of [1] to [9], an antiwear agent, a viscosity index improver, an antioxidant, a detergent, a dispersant, a flow, a curing agent, a corrosion inhibitor, A composition containing one or more additives selected from a seal compatibilizer, an antifoaming agent, a rust inhibitor, a corrosion inhibitor, a friction modifier, and a thickener.
[11] The composite polyester composition according to any one of [1] to [9], or the composition according to [10], a mineral oil, a fat compound, a polyolefin oil, a silicone oil, a perfluoropolyether oil, A composition comprising at least one or two or more media selected from aromatic ester oils and polyol ester lubricating oils.
[12] A lubricant comprising the composite polyester composition according to any one of [1] to [9], or the composition according to [10] or [11].
[13] Grease lubricating oil, mold release agent, engine oil for internal combustion engine, metal processing (cutting) oil, bearing oil, combustion engine fuel, vehicle engine oil, gear oil, automotive hydraulic oil, Aircraft lubricant, machine oil, turbine oil, bearing oil, hydraulic fluid, compressor / vacuum pump oil, refrigeration oil, metalworking lubricant, magnetic recording medium lubricant, micromachine lubricant, artificial bone The lubricant according to [12], which is used as a lubricant, a shock absorber oil or a rolling oil.
[14] including a step of mixing a polyvalent carboxylic acid containing at least two carboxyl groups, a dimer diol, and a monocarboxylic acid to obtain a mixture, and a step of dehydrating and condensing the mixture, the carbon of the polyvalent carboxylic acid A method for producing a composite polyester composition, wherein the number is 18 or less.
[15] In the step of obtaining the mixture, the equivalent ratio of mixing the dimer diol with respect to the polyvalent carboxylic acid is 1 to 3, and the equivalent ratio of mixing the monocarboxylic acid is 0.5 to 3. The method for producing a composite polyester composition as described in [14], which is a step of mixing as described above.
[16] The step of dehydrating and condensing is a step of adding 1 to 25% by mass of a hydrocarbon solvent having a boiling point of 110 to 160 ° C. with respect to the mixture, and advancing dehydrating condensation while azeotroping water. [14] or [15], wherein the method for producing a composite polyester composition.

  According to the present invention, a composite polyester composition capable of exhibiting high lubricating performance can be obtained. Furthermore, according to the present invention, a composite polyester composition that can exhibit high lubricating performance even under extreme pressure conditions can be obtained. For this reason, the composite polyester composition of the present invention is preferably used as a lubricant in various applications.

  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.

(1. Composite polyester composition)
The present invention relates to a composite polyester composition containing a predetermined polyester. The composite polyester composition of the present invention includes a polyester obtained by condensing a polyvalent carboxylic acid containing at least two carboxyl groups, a dimer diol, and a monocarboxylic acid. The carbon number of the polyvalent carboxylic acid is 18 or less.

  The polyvalent carboxylic acid used for the condensation of the polyester is a compound containing at least two carboxyl groups. It is preferable that 2 to 4 carboxyl groups are contained in one molecule, and more preferably 3 or 4 carboxyl groups. In addition, the carboxyl group in a molecule | numerator is connected with the linear or cyclic | annular bivalent or more aliphatic hydrocarbon or aromatic hydrocarbon.

  As the polyvalent carboxylic acid used in the present invention, any one of divalent to tetravalent polyvalent carboxylic acids may be used, or a plurality of types may be used. For example, a mixture of a divalent carboxylic acid and a trivalent carboxylic acid may be used, or a mixture of a divalent carboxylic acid, a trivalent carboxylic acid, and a tetravalent carboxylic acid may be used, A mixture of a trivalent carboxylic acid and a tetravalent carboxylic acid may be used. In addition, when divalent carboxylic acid is included, it is preferable that the content rate of divalent carboxylic acid is 90 mass% or less with respect to the total mass of polyvalent carboxylic acid, and it is 60 mass% or less. More preferably, it is more preferably 30% by mass or less.

The polyvalent carboxylic acid of the present invention has 18 or less carbon atoms. In the present invention, the carbon number of the polyvalent carboxylic acid represents the number of carbon atoms including the carbon atom constituting the carboxyl group.
The number of carbon atoms of the polyvalent carboxylic acid is preferably 5 or more, and more preferably 6 or more. Moreover, carbon number of polyvalent carboxylic acid is 18 or less, it is preferable that it is 16 or less, and it is more preferable that it is 14 or less.

  Examples of the polyvalent carboxylic acid having 18 or less carbon atoms and containing at least two carboxyl groups include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacin Examples include acid, dodecanedioic acid, brassic acid, cyclohexanedicarboxylic acid, phthalic acid, terephthalic acid, isophthalic acid, trimellitic acid and the like. Any one of these polyvalent carboxylic acids may be used alone, or two or more thereof may be mixed and used. Of these, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, brassic acid, cyclohexanedicarboxylic acid, phthalic acid, terephthalic acid, isophthalic acid, and trimellitic acid are preferably used.

  Specific examples of the polyvalent carboxylic acid that can be used in the present invention are shown below, but the present invention is not limited thereto.

  In the present invention, polyhydric carboxylic acid anhydrides can be used in place of polycarboxylic acids. The polyhydric carboxylic acid anhydride is a product obtained by intramolecular or intermolecular dehydration condensation of two COOHs of the above polycarboxylic acid. The preferred form is the same as above. Examples of the anhydrides include succinic anhydride, glutaric anhydride, adipic anhydride, maleic anhydride, phthalic anhydride, nadoic anhydride, methyl nadic anhydride, hexahydrophthalic anhydride and mixed polybasic anhydride Things are included.

Dimer diol is a glycol obtained by hydrogenating a dimer component (generally referred to as dimer acid) obtained by polymerizing an unsaturated fatty acid. Dimer diol is obtained as a mixture of geometric isomers of dimer diol having a branched structure and a cyclohexane ring. Examples of the dimer acid used as a raw material for the dimer diol include heavy fatty acids such as unsaturated fatty acids such as linoleic acid, oleic acid and linolenic acid, and dry oil fatty acids or semi-dry oil fatty acids obtained from tall oil, cottonseed oil and soybean oil. There is a dicarboxylic acid having 36 carbon atoms obtained by thermal polymerization of a coalescence, carboxylic acid having 18 carbon atoms.
In addition, it is preferable that carbon number of dimer diol is 24-48, It is more preferable that it is 28-44, It is further more preferable that it is 32-40.

Examples of the dimer diol that can be preferably used in the present invention include, for example, both-end aliphatic diols obtained by hydrogenating dimer acid, which is a dimer of unsaturated fatty acids (CAS No. 256664-32-7, CAS No. 157961-). 21-6), or both-end aliphatic diol (CAS No. 7313-30-6) obtained by dimerizing Z-form 9-octadecen-1-ol. In addition, the manufacturing method of dimer diol is not limited to these.
Representative examples of dimer diol include trade name Pripol 2033 (produced by Croda), trade name KX-501 (produced by Arakawa Chemical Industries), trade name Sovermol 650NS (produced by BASF), Sovermol 918 (produced by BASF), and the like. There is.

  As the monocarboxylic acid, a monovalent saturated fatty acid or unsaturated fatty acid, which is linear, branched or cyclic, can be used. Among these, the monocarboxylic acid is preferably a monovalent saturated fatty acid or an aromatic carboxylic acid.

The monocarboxylic acid preferably has 2 to 36 carbon atoms. Examples of the monovalent saturated fatty acid having 2 to 36 carbon atoms include acetic acid, propionic acid, butanoic acid, pentanoic acid, caproic acid, and enanthate. Acid, caprylic acid, pelargonic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, heptadecanoic acid, palmitic acid, pentadecanoic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, montanic acid, isopropionic acid , 2-ethylbutanoic acid, isoheptanoic acid, 2-ethylhexanoic acid, isononanoic acid, isodecanoic acid, isotridecanoic acid, isomyristic acid, isopalmitic acid, isostearic acid, isoarachidic acid, isotetracosanoic acid, isohexacosanoic acid and cyclohexanecarboxylic acid It is done.
Examples of the monovalent unsaturated fatty acid having 2 to 36 carbon atoms include linolenic acid, stearidonic acid, eicosapentaenoic acid, linoleic acid, arachidonic acid, oleic acid, elaidic acid, and erucic acid.

  The aromatic carboxylic acid means a compound in which at least one of hydrogen bonded to an aromatic ring is substituted with a carboxylic acid group, and includes those in which carboxylic acid is substituted with naphthalene or other condensed polycyclic aromatics. As the aromatic carboxylic acid compound, those containing a benzene ring, a naphthalene ring or a biphenyl ring as an aromatic ring are preferred, and preferred specific examples include benzoic acid, 1-naphthoic acid, transcinnamic acid, and 4-biphenylcarboxylic acid. be able to.

  Specific examples of the monocarboxylic acid that can be used in the present invention are shown below, but the present invention is not limited thereto.

  The composite polyester composition of the present invention includes a polyester obtained by mixing the polyvalent carboxylic acid, the dimer diol, and the monocarboxylic acid as described above and condensing the mixture. At least one polyester obtained by condensing the mixture is preferably represented by the following general formula (1).

Here, in the general formula (1), R represents an n-valent atomic group having a carbon number of (18-n) or less. R ¹ represents a dimer diol residue. R ² 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, an aryl group which may have a substituent, a substituent Represents a heteroaryl group which may have N represents an integer of 2 to 4.

  In the general formula (1), R represents a divalent to tetravalent atomic group. Moreover, the carbon number of R is 18 or less. Among these, in general formula (1), n is preferably an integer of 3 or 4, and R preferably represents a trivalent or tetravalent atomic group. That is, the polyvalent carboxylic acid containing at least two carboxyl groups is preferably a compound containing three or more carboxyl groups.

  The structure of the polyester when R is a trivalent atomic group can be represented by the general formula (2), and the structure of the polyester when R is a tetravalent atomic group can be represented by the general formula (3). .

Here, in General Formula (2), R represents a trivalent atomic group having 15 or less carbon atoms. R ¹ represents a dimer diol residue. R ² 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, an aryl group which may have a substituent, a substituent Represents a heteroaryl group which may have
In the general formula (3), R represents a tetravalent atomic group having 14 or less carbon atoms. R ¹ represents a dimer diol residue. R ² 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, an aryl group which may have a substituent, a substituent Represents a heteroaryl group which may have

  The atoms constituting the atomic group R are preferably carbon, hydrogen, and oxygen atoms. R is preferably an aliphatic hydrocarbon atomic group that may have a substituent, or an aromatic hydrocarbon atomic group that may have a substituent. Among these, R is particularly preferably an atomic group composed of a saturated aliphatic hydrocarbon which may have a substituent. By setting R to the above configuration, a composite polyester composition having excellent lubricating performance can be obtained.

  In said general formula (1)-(3), it is preferable that the carbon number of R is 2 or more, and it is more preferable that it is 3 or more. The carbon number of R is 16 or less, preferably 14 or less, and more preferably 13 or less.

R ¹ represents a dimer diol residue. Here, the residue of dimer diol refers to a group constituting a portion obtained by removing two hydroxyl groups from dimer diol.
The carbon number of the dimer diol residue represented by R ¹ is preferably 24 to 48, more preferably 28 to 44, and even more preferably 32 to 40.

R ² 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, an aryl group which may have a substituent, a substituent Represents a heteroaryl group which may have In addition, the substituent of each group that R ² may have is not particularly limited. As the substituent, the above substituents can be exemplified similarly.

The number of carbon atoms in the alkyl group part of the alkyl group which may have a substituent represented by R ² is preferably 3-17, more preferably 4-13, and 5-9. Is more preferable. The alkyl group represented by R ² may be linear or branched. R ² may be a cycloalkyl group.

The number of carbon atoms in the alkenyl group portion of the alkenyl group which may have a substituent represented by R ² is preferably 3-17, more preferably 4-13, and 5-9. Is more preferable. The alkyl group represented by R ² may be linear, branched or cyclic.

The number of carbon atoms in the aryl group portion of the aryl group or heteroaryl group that may have a substituent represented by R ² is preferably 6-20, and more preferably 6-12. Examples of the aryl group represented by R ² include a phenyl group and a naphthyl group, and among them, a phenyl group is particularly preferable. Examples of the heteroaryl group represented by R ² include 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, and more preferably an oxygen atom.

Among the above, R ² is preferably a branched alkyl group or an alkyl group containing an ether bond in the chain. By making R ² such a substituent, the lubricating performance of the composite polyester composition can be further enhanced.

Further, the above-mentioned general formula (1) or the number of carbon atoms in R ² of the general formula (2) is preferably 2 or more. Further, the carbon number of R is preferably 20 or less, preferably 18 or less, and more preferably 16 or less. By setting the carbon number of R and R ^{2 in} the above range, an increase in viscosity of the composite polyester composition can be suppressed even under extreme pressure conditions, and a composite polyester composition having a small friction coefficient can be obtained. Thereby, a composite polyester composition having high lubricating performance even under extreme pressure conditions can be obtained.

  When mixing the compound of polyvalent carboxylic acid, dimer diol and monocarboxylic acid, the equivalent ratio of mixing dimer diol with respect to polyvalent carboxylic acid is 1 to 3, and with respect to polyvalent carboxylic acid, It is preferable that the equivalent ratio with which the monocarboxylic acid is mixed is 0.5 to 3. That is, the mixing ratio is preferably polyvalent carboxylic acid: dimer diol: monocarboxylic acid = 1: 1 to 3: 0.5 to 3. The mixing ratio is more preferably 1: 1.2 to 2.8: 0.7 to 2.8, and more preferably 1: 1.5 to 2.5: 1 to 2.5. preferable. In particular, since the side chain of the polyester is preferably end-capped, the total equivalent of the polycarboxylic acid containing at least two carboxyl groups and the monocarboxylic acid should be the same or larger than the equivalent of the dimer diol. preferable.

  The composite polyester composition of the present invention preferably has a viscosity at 40 ° C. of 50 to 1650 mPas. The viscosity at 40 ° C. of the composite polyester composition is preferably 50 mPas or more, more preferably 70 mPas or more, and further preferably 100 mPas or more. The viscosity of the composite polyester composition at 40 ° C. is preferably 1650 mPas or less, more preferably 1200 mPas or less, and further preferably 1000 mPas or less. By setting the viscosity of the composite polyester composition within the above range, the coefficient of friction of the composite polyester composition can be kept low, thereby improving the lubrication performance.

  Since the lubricant of the present invention has the above-described configuration, it has an excellent feature that the increase in the friction coefficient from the normal fluid lubrication or elastohydrodynamic lubrication region to the extreme pressure region is small. Such an excellent effect is considered to be obtained when the polyester obtained in the present invention has a three-dimensional structure in which side chains are arranged radially. The polyester obtained in the present invention is composed of a polyvalent carboxylic acid capable of radially arranging side chains, a dimer diol that is connected to the polycarboxylic acid, and a monocarboxylic acid that serves as a terminal linking group of the dimer diol. A compound. In the present invention, a polyvalent carboxylic acid is used as a central atomic group and a side chain is provided, so that a large free volume can be ensured by the three-dimensional structure. Thereby, an increase in viscosity and friction coefficient can be suppressed even under high pressure. In addition, the carbon number of the polyvalent carboxylic acid constituting the central atomic group is 18 or less, and when this carbon number exceeds 18, it has the property of a linear polyester and the effect tends to be reduced.

  In this invention, in addition to predetermined polyester, you may further contain a light part. Here, the light component refers to a component having a low molecular weight, and refers to an ester in which all hydroxyl groups of dimer diol have reacted with a monocarboxylic acid, and a component having a smaller molecular weight. The viscosity of the composite polyester composition can be further lowered by allowing a liquid having a lower viscosity, such as a light component, to coexist. Thereby, high lubrication performance can be exhibited even under extreme pressure conditions.

In the composite polyester composition of the present invention, the ratio between the predetermined polyester and the light component is not particularly limited. In the aspect utilized for the use of the lubricant, the content of the light component is preferably 50% by mass or less, more preferably 45% by mass or less, and 40% by mass or less with respect to the predetermined polyester. More preferably. In addition, although there is no restriction | limiting in particular about a lower limit, it is preferable that it is 15 mass% or more.
The ratio between the predetermined polyester and the light component can be achieved by controlling the charging ratio of the three raw materials in the production method described later. Moreover, it can also adjust to a preferable range by isolate | separating a light part by distillation etc. and mixing with the remaining polyester by arbitrary ratios.
The composition ratio between the predetermined polyester and the light component containing dimer diol can be calculated by measuring gel permeation chromatography (GPC). The light component is easy to distinguish because the peak of GPC analysis appears sharply and its intensity is large.

  In the present invention, unreacted OH in the dimer diol may remain in the side chain of the polyester contained in the composite polyester composition, and unreacted COOH in the polycarboxylic acid or monocarboxylic acid. However, if OH and COOH remain, the hydroxyl value and the acid value increase, which may be undesirable depending on the application (for example, the use of a lubricant). In such a case, OH and COOH in the polyester can be eliminated by separate acylation and / or esterification treatment, and the hydroxyl value and acid value can be reduced.

In order to eliminate OH in the polyester, it is possible to obtain a polyester in which OH remains in the side chain and then acylate at least a part thereof. In the acylation treatment, monobasic acid (R ¹ COOH) or monobasic acid anhydride (R ¹ CO) ₂ O) is added to the polyester in which OH remains and heated to convert the remaining OH to OCOR ¹ . It is a process to convert. When the hydroxyl value is reduced by the acylation treatment, mixing with other oil-based media is preferable in terms of easy mixing.
Moreover, you may perform the process which lose | disappears COOH in polyester. For example, it can be esterified by treatment with diazomethane or the like.

The proportion of unreacted OH in the polyester can be determined by measuring ¹³ C-NMR. In the use of the lubricant, the residual ratio of OH in the polyester is preferably 0 to 40%, more preferably 0 to 35%, and further preferably 0 to 30%. In the same application, the acid value of the polyester (mg number of KOH required to neutralize 1 g of the sample) is preferably 0 to 50, more preferably 0 to 40, and 0 to 30. More preferably it is. However, it is not limited to this range.

(2. Manufacturing method of composite polyester composition)
The composite polyester composition of the present invention can be obtained by charging at least three raw materials of the above-described polyvalent carboxylic acid, dimer diol and monocarboxylic acid, followed by dehydration condensation. That is, the method for producing the composite polyester composition of the present invention includes a step of mixing a polyvalent carboxylic acid containing at least two carboxyl groups, a dimer diol, and a monocarboxylic acid to obtain a mixture, and a step of dehydrating and condensing the mixture. including. In the production process, two raw materials (for example, polyvalent carboxylic acid and dimer diol, or dimer diol and monocarboxylic acid) may be reacted first, and then the remaining raw materials may be reacted.

  The charging ratio (mixing ratio) of the polyvalent carboxylic acid, dimer diol and monocarboxylic acid is determined by an equivalent amount. The equivalent here means the chemical equivalent of COOH or OH in the reaction. When the number of COOH in one molecule of the polyvalent carboxylic acid is n and the number of moles is M1, the equivalent of the polyvalent carboxylic acid is defined as n × M1. Similarly, since the number of OH in one molecule of dimer diol is 2, the equivalent of dimer diol is defined as 2 × M 2 when the number of moles is M2. Since monocarboxylic acid has one OH in one molecule, M3 is defined as M3. The above ratio is a ratio of these n × M1, 2 × M2, and M3.

  In the present invention, the mixing ratio is preferably polyvalent carboxylic acid: dimer diol: monocarboxylic acid = 1: 1 to 3: 0.5 to 3. The mixing ratio is more preferably 1: 1.2 to 2.8: 0.7 to 2.8, and more preferably 1: 1.5 to 2.5: 1 to 2.5. preferable. In particular, since the side chain of the polyester is preferably end-capped, the total equivalent of the polycarboxylic acid containing at least two carboxyl groups and the monocarboxylic acid should be the same or larger than the equivalent of the dimer diol. preferable.

  The composite polyester composition of the present invention can be obtained by subjecting the mixture charged as described above to a dehydration condensation reaction in the presence or absence of a catalyst.

  In the dehydration condensation, it is desirable to heat or to make an appropriate amount of a solvent azeotropic with water exist. Thereby, dehydration proceeds smoothly without coloring the product. 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. If the amount to be added is too large, the liquid temperature will be in the vicinity of the solvent, and dehydration condensation will not proceed easily. On the other hand, if the amount is too small, azeotropy does not go smoothly. Accordingly, the addition amount is preferably 1 to 25% by mass, more preferably 2 to 20% by mass, and 3 to 15% by mass with respect to the total amount of polyol, polybasic acid or polybasic acid anhydride and monohydric alcohol. Particularly preferred is 5 to 12% by mass.

  Although the reaction is accelerated by using the catalyst, it is desirable not to use it because the post-treatment of removing the catalyst is complicated and causes coloring of the product. However, when used, normal conditions and procedures are used with normal catalysts. In this regard, reference can be made to Japanese Patent Publication Nos. 2001-501989, 2001-500499, 2001-507334, and 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 200 ° C, and particularly preferably 140 to 200 ° 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.

  As for the reaction time, since the theoretically generated water amount is calculated from the number of moles charged, it is preferable to carry out the reaction until the water amount is obtained, but it is difficult to complete the reaction completely. Even if the reaction is terminated when the theoretical water generation amount is 60 to 90%, the lubricity of the composite polyester composition is good. The reaction time is 1 to 24 hours, preferably 3 to 18 hours, more preferably 5 to 18 hours, and most preferably 6 to 15 hours.

After dehydration condensation and removal of volatile matter, the remaining OH may be acylated. When acylating, a suitable amount of monobasic acid (R ¹ COOH) or monobasic acid anhydride ((R ₁ CO) ₂ O), preferably monobasic acid anhydride ((R ¹ CO) ₂ O) is added Preferably, at least a part, preferably almost all of the remaining OH can be converted to OCOR ¹ by heating at 100 ° C. or higher, more preferably 120 ° C. or higher, particularly 150 ° C. or higher. It is preferable to remove the by-product volatile matter by distillation described later. R ¹ is an alkyl group or aryl group having 1 to 10 carbon atoms, preferably an alkyl group or aryl group having 1 to 6 carbon atoms, and is a methyl group, ethyl group, butyl group, or phenyl group. Are more preferable, a methyl group or a phenyl group is preferable, and a methyl group is particularly preferable.

  Further, after dehydration condensation and removal of volatile matter, an esterification treatment may be performed in order to eliminate the remaining COOH. The esterification treatment can be performed, for example, by adding diazomethane, and at least a part, preferably almost all of COOH can be converted into a methyl ester.

  By this reaction, a composite polyester composition containing a predetermined polyester and a soft component containing at least the ester produced as described above is obtained. After the dehydration-condensation reaction, if desired, after acylation treatment and / or esterification treatment, the resulting composite polyester composition can be used as it is for various uses, for example, as a lubricant. Various processes may be performed depending on the application.

  After completion of the reaction and the treatment after the reaction, it is preferable to perform filtration to remove dust and the like. When the composite polyester becomes solid, it can be melted out or taken out as a powder by reprecipitation.

(3. Composition)
The present invention may relate to a composition containing at least a composite polyester composition. For example, the composite polyester composition of the present invention and various additives and / or media can be added to the composition.
Examples of additives include antiwear agents, viscosity index improvers, antioxidants, detergents, dispersants, flow agents, curing agents, corrosion inhibitors, seal conformers, antifoaming agents, rust inhibitors, and corrosion inhibitors. , One or more selected from friction modifiers and thickeners.
By adding such an additive, a preferable function as a lubricant such as wear suppression can be imparted. Regarding the lubricant that can be used in the present invention, the description in paragraphs [0098] to [0165] of JP2011-89106A can be referred to.

Examples of the medium include one or more selected from mineral oils, fat compounds, polyolefin oils, silicone oils, perfluoropolyether oils, aromatic ester oils, and polyol ester lubricating oils.
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 JP-A-2011-89106 can be referred to.

(3-2. Properties of the composition of the present invention)
The composition of the present invention preferably has a viscosity at 40 ° C. of 1650 mPa · s or less, more preferably 1200 mPa · s or less, and even more preferably 1000 mPa · s or less. A smaller viscosity contributes to lower fuel consumption and is preferable, but it varies greatly depending on the viscosity of the base oil used, the structure of the compound of the present invention, the amount added, and the coexisting additive, and an appropriate viscosity is required depending on the use environment. It is necessary to match. However, since the present invention does not require the suppression of the base oil viscosity reduction under high temperature and extreme pressure conditions with the viscosity index improver in the current technology, the viscosity increase at low temperature due to the addition of the viscosity index improver. One of the features is that the effect of the low-viscosity base oil directly contributes to fuel consumption.

In the composition of the present invention, the constituent elements are preferably composed only of carbon, hydrogen, oxygen and nitrogen, and more preferably composed only of carbon, hydrogen and oxygen. In addition, there are various materials that are composed only of carbon, hydrogen, and oxygen as oils used as the oily medium. By combining these, it is possible to prepare a composition whose constituent elements consist only of carbon, hydrogen, oxygen and nitrogen.
The current lubricating oil usually contains phosphorus, sulfur and heavy metals. Lubricating oil used in a two-stroke engine that also burns lubricating oil together with fuel does not include phosphorus and heavy metals in consideration of environmental impact, but sulfur is included in about half of the lubricating oil used in a four-stroke engine. Yes. In other words, with the current lubrication technology, it is inferred that the formation of a boundary lubrication film with a sulfur content is indispensable. However, since it contains elemental sulfur, the load on the catalyst for exhaust gas purification is extremely high. large. Platinum and nickel are used for the exhaust gas purification catalyst, but the poisoning action of phosphorus and sulfur is a serious problem. From this point of view, the merit that the elements constituting the composition of the lubricating oil consist only of carbon, hydrogen, oxygen and nitrogen is very large. Furthermore, it consists of carbon, hydrogen and oxygen alone, which is optimal for industrial machinery other than engine oil, especially for lubricating oil for food production equipment. In the current technology, the elemental composition is taken into consideration for the environment at the expense of the friction coefficient. This is also a very preferable technique for metal cutting and machining lubricants that require a large amount of water for cooling.

(4. Method for preparing the composition of the present invention)
The composition of the present invention can be prepared by adding the complex polyester composition in an oily medium or an aqueous medium, and dissolving and / or dispersing it. Dissolution and / or dispersion may be performed under heating. The amount of the composite polyester composition added is preferably 10% by mass or more with respect to the mass of the oily medium. However, it is not limited to this range, and may be outside the above range as long as the compound is an amount sufficient to exhibit a friction reducing action.

(5. Use of the composition of the present invention)
The composition of the present invention is useful as a lubricant. That is, the present invention also relates to a lubricant including the above-described composite polyester composition or the above-described composition.
The lubricant of the present invention is supplied, for example, between two sliding surfaces, and can be used to reduce friction. The composition of the present invention can form a film on the sliding surface. As for the material of the sliding surface, in steel, specifically, carbon steel for machine structure, alloy steel for structural machinery such as nickel chrome steel, nickel chrome molybdenum steel, chrome steel, chrome molybdenum steel, aluminum chrome molybdenum steel, Examples include stainless steel and multi-aged 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.
In addition, about the material of a sliding surface, description of Paragraph [0168]-[0175] of Unexamined-Japanese-Patent No. 2011-89106 can be referred.

  The lubricant of the present invention can be used for various applications. For example, lubricating oil for grease, release agent, engine oil for internal combustion engine, oil for metal processing (cutting), oil for bearing, fuel for combustion engine, vehicle engine oil, gear oil, hydraulic oil for automobile, ship / aircraft Lubricant, machine oil, turbine oil, bearing oil, hydraulic fluid, compressor / vacuum pump oil, refrigerator oil, metalworking lubricant, magnetic recording medium lubricant, micromachine lubricant, artificial bone lubricant It can be used as an agent, 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. .

As a lubricant for metal processing that does not contain chlorine compounds, for example, when hot rolling metal materials such as steel materials and Al alloys, or when performing processing such as cutting, cold rolling oil of aluminum, cutting oil, As metal processing oil such as grinding oil, drawing oil, press processing oil and plastic processing oil of metal, especially as a deterrent for wear, breakage and surface roughness during high speed and high load processing, as well as broaching and gun drilling It is also useful as a metal working oil composition that can be applied to low speed and heavy cutting.
Further, it can be used for various grease lubricants, magnetic recording medium lubricants, micromachine lubricants, artificial bone lubricants, and the like. In addition, since the elemental composition of the composition can be a carbohydrate, for example, polyoxyethylene ether widely used in cake mix, salad dressing, shortening oil, chocolate, etc. as an emulsifying, dispersing or solubilizing agent is used. By using the composition of the sorbitan fatty acid ester containing edible oil as the base oil as the lubricating oil, a high-performance lubricating oil that is completely harmless to the human body can be used for lubrication of food production line manufacturing equipment and medical equipment members.
Furthermore, the 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 composition of this invention can be utilized for various uses also as a mold 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. One embodiment of the release agent is an embodiment containing 0.01 to 10 parts by mass (preferably 0.1 to 5 parts by mass) of the composite polyester composition with respect to 100 parts by mass of a resin such as a polycarbonate resin.
Moreover, it can also be used as an antifouling agent for preventing the soiling of the textile product by kneading or applying to the textile product such as clothing in advance to promote the removal of the soiling attached to the textile product.

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. In the following, Examples 1 to 5 are read as Reference Examples 1 to 5, respectively.

(Examples 1 to 25)
<Dimer diol>
The dimer diol used in the present invention is, for example, a bi-terminal aliphatic diol obtained by hydrogenating dimer acid, which is a dimer of unsaturated fatty acids (CAS number 256664-32-2-7, CAS number 157961-21-6), Alternatively, both terminal aliphatic diols (CAS No. 7313-30-6) obtained by dimerization of Z-form 9-octadecen-1-ol and the like. The production method of dimer diol is not limited to these. Typical examples include trade name Pripol 2033 (produced by Croda), trade name KX-501 (produced by Arakawa Chemical Industries), trade name Sovermol 650NS (produced by BASF), and Sovermol 918 (produced by BASF). In Examples 1 to 25, Sovermol 650NS (S-650NS) was used as the dimer diol.

<Polyvalent carboxylic acid>
The polyvalent carboxylic acids used in the examples of the present invention are as follows.

<Monocarboxylic acid>
The monocarboxylic acids used in the examples of the present invention are as follows.

<Synthesis of polyester>
The dimer diol described in Table 1, the polyvalent carboxylic acid, and the monocarboxylic acid were charged into a reaction vessel equipped with a Dean-Stark dehydrator so as to have a mass part described in Table 1. Then, it stirred at liquid temperature 160-200 degreeC for 12 hours. Water was generated during stirring, and 5 parts by mass of water was removed. The mixture was allowed to cool to room temperature to obtain a polyester composition (PEE 1 to 81) as a yellow transparent liquid.
In Examples 1 to 25, Sovermol 650NS was used as the dimer diol, but similar ones were obtained by using Pripol 2033 (manufactured by Croda) instead.

<Preparation of composite polyester composition>
Each polyester composition obtained in Examples 1 to 25 (PEE 1 to 81) and mineral oil (100 neutral oil, viscosity at 100 ° C., 4.4 mm / s ² ) were mixed at a mass ratio of 25/75. A lubricant containing 2.0% by mass of calcium sulfonate as a metal detergent was prepared. The friction coefficient of the lubricant was measured by the following method.

<Evaluation>
Evaluation assuming extreme pressure conditions was performed using a vibration type friction and wear tester (manufactured by Optimol Instruments Prutechnik GmbH, trade name: SRV 4), using a vibration frequency of 100 Hz, an amplitude of 2.0 mm, a load of 30 N, a temperature of 65 ° C., Test piece: The test was performed by measuring the coefficient of friction at a point contact (ball) and a test time of 30 minutes.
Generally, the friction coefficient obtained on the assumption of extreme pressure conditions is obtained as a value larger than the friction coefficient in a normal fluid lubrication region or elastohydrodynamic lubrication region. For this reason, those having a small coefficient of friction under extreme pressure conditions and good evaluation below naturally have a small coefficient of friction in a normal fluid lubrication region and elastohydrodynamic lubrication region, and the evaluation is good. Table 1 below shows the evaluation results of the coefficient of friction using an SRV4 testing machine assuming extreme pressure conditions.
Rank A: Friction coefficient <0.05
B rank: 0.05 ≦ coefficient of friction <0.06
C rank: 0.06 ≦ friction coefficient <0.07
D rank: friction coefficient ≧ 0.07

(Comparative Example 1)
Instead of the polyester composition of Example 1, in Comparative Example 1, the compound (CO-1) described in Example 1 of JP-A-2002-241777 was used. The compound described in Example 1 of JP-A-2002-241777 includes hydrogenated dimer diol (dimer diol having 34 to 38 carbon atoms) (DD-C1), 2-ethylhexanoic acid (MC-C1), 3 , 5,5-trimethylhexanoic acid (MC-C2).
Except having used said compound, the composite polyester composition was prepared similarly to Example 1, and the friction coefficient was measured similarly. The results are shown in Table 1.

(Comparative Example 2)
Instead of the polyester composition of Example 1, in Comparative Example 2, the compound (CO-2) described in Example 7 of JP-A-2002-241777 was used. The compound described in Example 7 of JP-A-2002-241777 includes hydrogenated dimer diol (36-carbon dimer diol) (DD-C2) and hydrogenated dimer acid (36-carbon dimer acid) (PC -C2) and a polycondensate of isotridecanoic acid (MC-C3).
Except having used said compound, the composite polyester composition was prepared similarly to Example 1, and the friction coefficient was measured similarly. The results are shown in Table 1.

As can be seen from Table 1, it can be seen that the friction coefficient under extreme pressure conditions of the composite polyester compositions of Examples 1 to 25 is kept low. In addition, from this, it is assumed that the friction coefficient in the normal fluid lubrication area | region and the elastic fluid lubrication area | region of the composite polyester composition of Examples 1-25 is also restrained low. That is, the composite polyester compositions of Examples 1 to 25 can exhibit excellent lubricating performance under normal conditions and extreme pressure conditions.
On the other hand, it can be seen that the coefficient of friction of the composite polyester compositions of Comparative Examples 1 and 2 is increased under extreme pressure conditions. That is, the composite polyester compositions of Comparative Examples 1 and 2 cannot exhibit excellent lubricating performance under extreme pressure conditions.
In Examples 7 to 12, 15 and 16, 22 to 25, a non-aromatic compound having a valence of 3 or more is used as the polyvalent carboxylic acid. Therefore, it can be seen that the composite polyester composition has a coefficient of friction of less than 0.05 and can exhibit better lubricating performance.

  According to the present invention, a composite polyester composition capable of exhibiting high lubricating performance can be obtained. Furthermore, according to the present invention, a composite polyester composition that can exhibit high lubricating performance even under extreme pressure conditions can be obtained. For this reason, the composite polyester composition of the present invention can be suitably used as an automotive lubricating oil such as an internal combustion engine such as an automobile engine, a gear oil, an automatic transmission fluid, and a shock absorber oil. Probability is high.

Claims (13)

Three or more carboxyl groups and unrealized carbon atoms and 18 or less polycarboxylic acid, a dimer diol, a lubricant containing including bicomponent polyester composition of the polyester obtained by condensation of monocarboxylic acids. The lubricant according to claim 1, wherein at least one of the polyesters is represented by the following general formula (1).

(In General Formula (1), R represents an n-valent atomic group having (18-n) or less carbon atoms, R ¹ represents a residue of the dimer diol, and R ² has a substituent. A good alkyl group, a cycloalkyl group which may have a substituent, an alkenyl group which may have a substituent, an aryl group which may have a substituent, and a heteroaryl group which may have a substituent. N represents an integer of 3 or 4.) 3. The lubricant according to claim 2, wherein, in the general formula (1), R has 2 or more carbon atoms. In the said General formula (1), R is an atomic group which consists of a saturated aliphatic hydrocarbon which may have a substituent, The lubricant of Claim 2 or 3 characterized by the above-mentioned. The lubricant according to any one of claims 2 to 4, wherein in the general formula (1), R ² has 2 or more carbon atoms. In the general formula (1), R ² is a lubricant according to any one of claims 2-5, characterized in that in the branched alkyl group Matakusari is an alkyl group containing an ether bond. The lubricant according to any one of claims 1 to 6, wherein the composite polyester composition has a viscosity at 40 ° C of 50 to 1650 mPas. Antiwear, viscosity index improver, antioxidant, detergent, dispersant, flow, curing agent, corrosion inhibitor, seal conformant, antifoam agent, rust inhibitor, corrosion inhibitor, friction modifier, and increase The lubricant according to any one of claims 1 to 7, further comprising one or two or more additives selected from a lubricant . Any of the Claims 1-8 which further contain the 1 type (s) or 2 or more types of medium selected from mineral oil, fat compound, polyolefin oil, silicone oil, perfluoropolyether oil, aromatic ester oil, and polyol ester lubricating oil. The lubricant according to claim 1 . Grease lubricants, mold release agents, engine oils for internal combustion engines, metal processing (cutting) oils, bearing oils, combustion engine fuels, vehicle engine oils, gear oils, automotive hydraulic oils, marine and aircraft lubricants Oil, machine oil, turbine oil, bearing oil, hydraulic oil, compressor / vacuum pump oil, refrigerator oil, metalworking lubricant, magnetic recording medium lubricant, micromachine lubricant, artificial bone lubricant, The lubricant according to any one of claims 1 to 9, wherein the lubricant is used as a shock absorber oil or a rolling oil. And three or more carboxyl groups-containing viewed carbon atoms and 18 or less polycarboxylic acid, dimer diol and a step of obtaining a mixture the mixture with monocarboxylic acids, the mixture is dehydration condensation step of including lubricant Manufacturing method. The step of obtaining the mixture is performed such that the equivalent ratio of mixing the dimer diol is 1 to 3 and the equivalent ratio of mixing the monocarboxylic acid is 0.5 to 3 with respect to the polyvalent carboxylic acid. The method for producing a lubricant according to claim 11 , wherein The dehydrating and condensing step includes a step of adding 1 to 25% by mass of a hydrocarbon solvent having a boiling point of 110 to 160 ° C. with respect to the mixture, and advancing dehydrating condensation while azeotroping water. The method for producing a lubricant according to claim 11 or 12 ,