JP2023084942A - Water-soluble metal processing oil agent - Google Patents

Abstract

To provide a novel water-soluble metal processing oil agent that is in demand.SOLUTION: A water-soluble metal processing oil agent comprises: a base oil (A); and an ether carboxylic acid (B) represented by a following general formula (b-1), where a content of the ether carboxylic acid (B) is 0.1 to 10 mass% based on a total amount of the water-soluble metal processing oil agent. In the formula, A is an alkylene group having 1 to 4 carbon atoms, and if A is present more than one, the A may be the same group or different groups from each other. B is a single bond or an alkylene group having 1 to 4 carbon atoms, n is an integer of 1 to 100, and R is a hydrocarbon group.SELECTED DRAWING: None

Description

The present invention relates to a water-soluble metalworking fluid and a metalworking fluid obtained by blending the water-soluble metalworking fluid with dilution water.

2. Description of the Related Art In the field of metalworking such as cutting and grinding, metalworking fluids are used for the purpose of improving the workability of workpieces and suppressing wear of working tools.
Metalworking fluids include oil-based metalworking fluids containing oils such as mineral oils, synthetic oils, and animal and vegetable oils as main components, and water-soluble metalworking fluids that are made water-soluble by blending oil with a surface-active compound. In recent years, water-soluble metalworking fluids have come to be used for safety reasons such as low risk of fire.

For example, Patent Document 1 discloses a water-soluble processing oil containing methyldicyclohexylamine. The water-soluble working fluid is diluted with diluent water to obtain a metal working fluid, which is then used for metal working. Further, Patent Document 2 also discloses a water-soluble metal working oil containing an ether carboxylic acid.

WO2010/113594 Chinese Patent Publication No. 106893622

On the other hand, machine tools have sliding surfaces for moving tools and work materials in arbitrary directions, and greases and lubricating oil compositions have been used to facilitate sliding movements. . In recent years, in order to reduce the size and cost of machine tools, there has been an increase in equipment that does not have an oil skimmer, which is another oil separation device, installed in the cutting oil tank.
However, when the grease used for the sliding surface is mixed with the cutting oil tank installed in the machine tool, it promotes demulsification of the water-soluble metalworking fluid, resulting in deterioration of the water-soluble metalworking fluid. Under these circumstances, a novel water-soluble metal working fluid is required.

［式中、
Ａは炭素数１～４のアルキレン基であり、Ａが複数存在する場合、複数のＡは、同一の基であってもよく、互いに異なる基であってもよい。
Ｂは単結合または炭素数１～４のアルキレン基であり、
ｎは１～１００の整数であり、
Ｒは炭化水素基である。］
［２］前記一般式（ｂ－１）中のＢがメチレン基である、［１］に記載の水溶性金属加工油剤。
［３］エーテルカルボン酸（Ｂ）のＨＬＢが５．０以上である、［１］または［２］に記載の水溶性金属加工油剤。
［４］エーテルカルボン酸（Ｂ）のＨＬＢが６．０超である、［１］または［２］に記載の水溶性金属加工油剤。
［５］前記一般式（ｂ－１）中のＡが、エチレン基である、［１］～［４］のいずれか一項に記載の水溶性金属加工油剤。
［６］前記一般式（ｂ－１）中のｎが６以上である、［１］～［４］のいずれか一項に記載の水溶性金属加工油剤。
［７］前記一般式（ｂ－１）中のＲが、炭素数１０～３０の炭化水素基である、［１］～［６］のいずれか一項に記載の水溶性金属加工油剤。
［８］非イオン性界面活性剤（Ｃ）をさらに含む、［１］～［７］のいずれか一項に記載の水溶性金属加工油剤。
［９］非イオン性界面活性剤（Ｃ）と、エーテルカルボン酸（Ｂ）との含有量比〔（Ｃ）／（Ｂ）〕が、質量比で、１～２５である、［８］に記載の水溶性金属加工油剤。
［１０］アミン化合物（Ｄ）をさらに含む、［１］～［９］のいずれか一項に記載の水溶性金属加工油剤。
［１１］アミン化合物（Ｄ）と、エーテルカルボン酸（Ｂ）との含有量比〔（Ｄ）／（Ｂ）〕が、質量比で、１～１６６である、［１０］に記載の水溶性金属加工油剤。
［１２］［１］～［１１］のいずれか一項に記載の水溶性金属加工油剤を希釈してなる、金属加工液。
［１３］乳化阻害物質を使用する工作機械による金属加工の際に使用する、［１２］に記載の金属加工液。
［１４］前記乳化阻害物質が、グリースである、［１３］に記載の金属加工液。 The present invention provides an aqueous metalworking fluid containing a predetermined amount of a specific ethercarboxylic acid. Specifically, the present invention provides, for example, the following aspects [1] to [14].
[1] A water-soluble metalworking fluid containing a base oil (A) and an ether carboxylic acid (B) represented by the following general formula (b-1),
A water-soluble metalworking fluid having an ethercarboxylic acid (B) content of 0.1 to 10% by mass based on the total amount of the water-soluble metalworking fluid.

[In the formula,
A is an alkylene group having 1 to 4 carbon atoms, and when there are a plurality of A's, the plurality of A's may be the same group or different groups.
B is a single bond or an alkylene group having 1 to 4 carbon atoms,
n is an integer from 1 to 100,
R is a hydrocarbon group. ]
[2] The water-soluble metalworking fluid according to [1], wherein B in the general formula (b-1) is a methylene group.
[3] The water-soluble metal working fluid according to [1] or [2], wherein the ether carboxylic acid (B) has an HLB of 5.0 or more.
[4] The water-soluble metal working fluid according to [1] or [2], wherein the ether carboxylic acid (B) has an HLB of more than 6.0.
[5] The water-soluble metalworking fluid according to any one of [1] to [4], wherein A in the general formula (b-1) is an ethylene group.
[6] The water-soluble metal working fluid according to any one of [1] to [4], wherein n in the general formula (b-1) is 6 or more.
[7] The water-soluble metalworking fluid according to any one of [1] to [6], wherein R in the general formula (b-1) is a hydrocarbon group having 10 to 30 carbon atoms.
[8] The water-soluble metalworking fluid according to any one of [1] to [7], further comprising a nonionic surfactant (C).
[9] The content ratio [(C)/(B)] of the nonionic surfactant (C) and the ether carboxylic acid (B) is 1 to 25 in mass ratio, [8] A water-soluble metalworking fluid as described.
[10] The water-soluble metalworking fluid according to any one of [1] to [9], further comprising an amine compound (D).
[11] The water-soluble according to [10], wherein the content ratio [(D)/(B)] of the amine compound (D) and the ether carboxylic acid (B) is 1 to 166 by mass. Metalworking fluid.
[12] A metalworking fluid obtained by diluting the water-soluble metalworking fluid according to any one of [1] to [11].
[13] The metalworking fluid according to [12], which is used for metalworking with a machine tool using an emulsification inhibitor.
[14] The metal working fluid according to [13], wherein the emulsification inhibitor is grease.

The water-soluble metalworking fluid of one preferred embodiment of the present invention suppresses emulsification failure of the metalworking fluid even if machine tool grease is mixed in the cutting oil tank when it is made into a metalworking fluid.

For the numerical ranges described herein, the upper and lower limits can be combined arbitrarily. For example, when the numerical range is described as "preferably 30 to 100, more preferably 40 to 80", the range of "30 to 80" and the range of "40 to 100" are also described in this specification. included in the specified numerical range. Further, for example, when the numerical range is described as "preferably 30 or more, more preferably 40 or more, and preferably 100 or less, more preferably 80 or less", "30 to 80" Ranges and ranges from "40 to 100" are also included in the numerical ranges described herein.
In addition, as a numerical range described in this specification, for example, "60 to 100" means a range of "60 or more and 100 or less".

In this specification, the two terms "metal working fluid" and "metal working fluid" are used after distinguishing between them according to the water content as shown below.
- "Metalworking fluid": The content of water is 0 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the total amount of components other than water.
- "Metalworking fluid": The content of water is more than 100 parts by mass with respect to 100 parts by mass of the total amount of components other than water.
The "metalworking fluid" is a stock solution of the metalworking fluid before being diluted with diluent water to form a metalworking fluid, and is in a suitable form during transportation and storage before being used for metalworking. The "metalworking fluid" is obtained by adding diluent water to the undiluted metalworking oil and diluting it, and is in a form suitable for use in metalworking.

[Structure of water-soluble metalworking fluid]
The water-soluble metalworking fluid of the present invention contains a base oil (A) and an ether carboxylic acid (B) represented by the following general formula (b-1). The water-soluble metalworking fluid of one embodiment of the present invention contains a compound represented by the following general formula (b-1) to inhibit emulsification of machine tool grease or the like when used as a metalworking fluid. It is possible to effectively suppress the demulsification of the metal working fluid even if a component that causes the metal working fluid is mixed.

The water-soluble metalworking fluid of the present invention contains a base oil (A) and an ether carboxylic acid (B) represented by the above general formula (b-1), but other components other than these components may contain.
For example, the water-soluble metalworking fluid of one aspect of the present invention may contain one or more selected from nonionic surfactants (C), amine compounds (D), and fatty acids (E). Further, the water-soluble metalworking fluid of one aspect of the present invention may contain water (F). In addition, the water-soluble metalworking fluid of one embodiment of the present invention may contain other components other than the components (A) to (F) within a range that does not impair the effects of the present invention.
By adjusting the content and content ratio of water and other components, emulsion-type oils classified as Class A1 and soluble-type oils classified as Class A2, as defined in JIS K2241:2017, can be obtained. can be prepared to

In one aspect of the present invention, the total content of components (A) to (B) is preferably 10% by mass or more, more preferably 20% by mass, based on the total amount (100% by mass) of the water-soluble metalworking fluid. More preferably 25% by mass or more, still more preferably 30% by mass or more, particularly preferably 35% by mass or more, and 100% by mass or less, 90% by mass or less, 80% by mass or less, and 70% by mass or less , 60% by mass or less, 50% by mass or less, or 45% by mass or less.

In one aspect of the present invention, the total content of components (A) to (C) is preferably 10% by mass or more, more preferably 20% by mass, based on the total amount (100% by mass) of the water-soluble metalworking fluid. Above, more preferably 30% by mass or more, still more preferably 33% by mass or more, particularly preferably 36% by mass or more, and 100% by mass or less, 90% by mass or less, 80% by mass or less, and 70% by mass or less , 60% by mass or less, 50% by mass or less, 48% by mass or less, or 45% by mass or less.

In one aspect of the present invention, the total content of components (A) to (D) is preferably 10% by mass or more, more preferably 20% by mass, based on the total amount (100% by mass) of the water-soluble metalworking fluid. Above, more preferably 30% by mass or more, still more preferably 40% by mass or more, particularly preferably 50% by mass or more, and 100% by mass or less, 95% by mass or less, 90% by mass or less, and 85% by mass or less , 80% by mass or less, 75% by mass or less, or 70% by mass or less.

In one aspect of the present invention, the total content of components (A) to (E) is preferably 50% by mass or more, more preferably 55% by mass, based on the total amount (100% by mass) of the water-soluble metalworking fluid. More preferably 60% by mass or more, still more preferably 65% by mass or more, particularly preferably 70% by mass or more, and 100% by mass or less, 97% by mass or less, 95% by mass or less, and 93% by mass or less , 90% by mass or less, 87% by mass or less, or 85% by mass or less.

In one aspect of the present invention, the total content of components (A) to (F) is preferably 50% by mass or more, more preferably 60% by mass, based on the total amount (100% by mass) of the water-soluble metalworking fluid. More preferably 65% by mass or more, still more preferably 70% by mass or more, particularly preferably 75% by mass or more, and 100% by mass or less, 99% by mass or less, 98% by mass or less, 97% by mass or less , 96% by mass or less, or 95% by mass or less.

In one aspect of the present invention, the content ratio [(C)/(B)] of the nonionic surfactant (C) and the ether carboxylic acid (B) is preferably 1.0 or more in terms of mass ratio. , more preferably 1.10 or more, still more preferably 1.15 or more, still more preferably 1.20 or more, particularly preferably 1.25 or more, and preferably 25.0 or less, more preferably 20. 0 or less, more preferably 15.0 or less, particularly preferably 10.0 or less, 8.5 or less, 8.0 or less, 7.5 or less, 7.0 or less, 6.5 or less, It may be 0 or less, 5.5 or less, or 5.0 or less.

In one aspect of the present invention, the content ratio [(D)/(B)] of the amine compound (D) and the ether carboxylic acid (B) is preferably 1 or more, more preferably 1.0% by mass. 5 or more, more preferably 2.0 or more, still more preferably 2.5 or more, still more preferably 3.0 or more, still more preferably 3.5 or more, still more preferably 4.0 or more, still more preferably 4.5 above, particularly preferably 5.0 or more, and may be 6.0 or more, 6.5 or more, 7.0 or more, 7.5 or more, or 8.0 or more, and preferably 166 or less , more preferably 120 or less, still more preferably 100 or less, still more preferably 90 or less, still more preferably 80 or less, still more preferably 70 or less, particularly preferably 60 or less, and 56 or less, 50 or less, 45 or less , 40 or less, or 35 or less.
Each component contained in the water-soluble metalworking fluid according to one embodiment of the present invention will be described below.

<Component (A): Base oil>
The water-soluble metalworking fluid of the present invention contains a base oil (A). By containing the base oil (A), a water-soluble metalworking fluid that can be a metalworking fluid with good workability can be obtained.
In addition, in the water-soluble metalworking fluid of one embodiment of the present invention, the base oil (A) may be used alone or in combination of two or more.

From the above viewpoint, in one aspect of the present invention, the content of the base oil (A) is preferably 9% by mass or more, more preferably 12% by mass, based on the total amount (100% by mass) of the water-soluble metalworking fluid. More preferably 14% by mass or more, more preferably 20% by mass or more, still more preferably 25% by mass or more, particularly preferably 30% by mass or more, and preferably 80% by mass or less, more preferably 70% by mass % or less, more preferably 60 mass % or less, and particularly preferably 50 mass % or less.
In the case of an emulsion-type oil agent classified as Class A1 as defined in JIS K2241:2017, the content of the base oil (A) is 20% by mass or more based on the total amount (100% by mass) of the oil agent. , 25% by mass or more, 30% by mass or more, 35% by mass or more, or 40% by mass or more.
In addition, in the case of a soluble oil agent classified as Class A2 as defined in JIS K2241:2017, the content of the base oil (A) is 50% by mass or less based on the total amount (100% by mass) of the oil agent. , 45% by mass or less, 40% by mass or less, 35% by mass or less, or 30% by mass or less.

The base oil (A) used in one aspect of the present invention includes at least one selected from mineral oils and synthetic oils.
Mineral oils include, for example, atmospheric residual oils obtained by atmospheric distillation of crude oils such as paraffinic crude oils, intermediate crude oils, and naphthenic crude oils; distillates obtained by vacuum distillation of these atmospheric residual oils. a refined oil obtained by subjecting the distillate to one or more refining treatments such as solvent deasphalting, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, and hydrorefining; and the like.

Examples of synthetic oils include α-olefins, homopolymers thereof, α-olefin copolymers (for example, α-olefin copolymers having 8 to 14 carbon atoms such as ethylene-α-olefin copolymers), and the like. polyα-olefin; isoparaffin; polyalkylene glycol; polyol ester, dibasic acid ester, ester-based oil such as phosphate ester; ether-based oil such as polyphenyl ether; Synthetic oil (GTL) obtained by isomerizing wax (GTL wax (Gas To Liquids WAX)) produced by Etc.

Among these, the base oil (A) used in one aspect of the present invention is at least one selected from mineral oils classified into groups 2 and 3 of the API (American Petroleum Institute) base oil category, and synthetic oils. preferably included.

The 40° C. kinematic viscosity of the base oil (A) of one embodiment of the present invention is 3.0 mm ² /s or more, 3.5 mm ² /s or more, 4.0 mm ² /s or more, 4.5 mm ² /s or more, 5.0 mm ² /s or more, 5.5 mm ² /s or more, 6.0 mm ² /s or more, 6.5 mm ² /s or more, or 7.0 mm ² /s or more, or 100 mm ² /s 90 mm ² /s or less, 80 mm ² /s or less, 70 mm ² /s or less, 60 mm 2 /s or less, 50 mm ^{2 /} s or less, 45 mm ² /s or less, 40 mm ² /s or less, 35 mm ² /s or less, It may be 30 mm ² /s or less, 25 mm ² /s or less, or 20 mm ² /s or less.

The viscosity index of the lubricating base oil of one aspect of the present invention may be 70 or higher, 80 or higher, 85 or higher, 90 or higher, 95 or higher, or 100 or higher.
As used herein, kinematic viscosity and viscosity index mean values measured or calculated according to JIS K2283:2000.

<Component (B): Ether carboxylic acid>
The water-soluble metalworking fluid of the present invention contains an ether carboxylic acid (B) represented by the following general formula (b-1).

The present inventors prepared a water-soluble metalworking fluid containing an ether carboxylic acid (B) having a carboxyl group in its structure, and diluted the water-soluble metalworking fluid with dilution water to obtain a metalworking fluid. In this case, it was found that even if grease for machine tools is mixed in the cutting oil tank, demulsification of the metal working fluid is suppressed. The metalworking fluid using the water-soluble metalworking fluid of the present invention is less likely to deteriorate in quality even if the grease used for the sliding surface is mixed with the cutting oil tank, so it is possible to extend the period of use. .

In the general formula (b-1), A is an alkylene group having 1 to 4 carbon atoms, and when there are a plurality of A's, the plurality of A's may be the same group or different groups. may As used herein, an "alkylene group" means a linear, cyclic or branched divalent saturated aliphatic hydrocarbon group having the specified number of carbon atoms.
Examples of the alkylene group that can be selected as A include ethylene groups such as a methylene group, a 1,1-ethylene group and a 1,2-ethylene group, 1,3-propylene, 1,2-propylene, 2,2 - A propylene group such as propylene, and a butylene group. The above groups also include structural isomers.
Among these, the alkylene group that can be selected as A is preferably one or more groups selected from an ethylene group and a propylene group.
Further, when there are a plurality of A, the plurality of A is an ethylene group alone, a propylene group alone, or a combination of an ethylene group and a propylene group (that is, -AO- is an ethylene oxide (EO) group and a propylene oxide ( PO) groups may be randomly or block-bonded), but preferably contain one or more groups selected from ethylene groups and propylene groups, and at least More preferably, it contains ethylene groups, and more preferably all ethylene groups.

In the general formula (b-1), B is a single bond or an alkylene group having 1 to 4 carbon atoms. Examples of the alkylene group that can be selected as B include the same groups as those described above for A. Among them, the alkylene group that can be selected as B is preferably a linear alkylene group having 1 to 3 carbon atoms, more preferably a methylene group.

In the general formula (b-1), n is 1 or more, preferably 2 or more, more preferably 3 or more, still more preferably 4 or more, from the viewpoint of a metalworking fluid that effectively suppresses demulsification. More preferably 5 or more, more preferably 6 or more, still more preferably 7 or more, still more preferably 8 or more, still more preferably 9 or more, and particularly preferably 10 or more.
In the general formula (b-1), n is 100 or less, 90 or less, 80 or less, 70 or less, 60 or less, 50 or less, 40 or less, 30 or less, 20 or less, 15 or less, or 10 or less. can do.

In the general formula (b-1), R represents a hydrocarbon group. As used herein, "hydrocarbon group" means a group obtained by removing one hydrogen atom from a linear, cyclic or branched saturated or unsaturated hydrocarbon having a specified number of carbon atoms. . Specific examples include alkyl groups, alkenyl groups, cycloalkyl groups, and aryl groups.

Examples of alkyl groups include propyl groups such as methyl group, ethyl group, n-propyl group and isopropyl group, butyl groups such as n-butyl group, isobutyl group, s-butyl group and t-butyl group, pentyl groups, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, henicosyl group, docosyl group , a tricosyl group, a tetracosyl group, and the like. The above groups also include structural isomers.

Examples of alkenyl groups include vinyl, propenyl, isopropenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl group, hexadecenyl group, heptadecenyl group, octadecenyl group (oleyl group), nonadecenyl group, icosenyl group, henicosenyl group, docosenyl group, tricosenyl group, tetracosenyl group and the like. The above groups also include structural isomers.

Cycloalkyl groups include, for example, a cyclopentyl group, a cyclohexyl group, and the like. In the cycloalkyl group, the hydrogen atom to which at least one ring-forming carbon is bonded is substituted with a substituent (an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 1 to 6 carbon atoms, a phenyl group, etc.). good too. Cycloalkyl groups having such substituents include, for example, methylcyclohexyl, ethylcyclohexyl, and dimethylcyclohexyl groups.

Examples of the aryl group include phenyl group, tolyl group, xylyl group, naphthyl group and the like.
In the aryl group, the hydrogen atom to which at least one ring-forming carbon is bonded is substituted with a substituent (an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 1 to 6 carbon atoms, a cycloalkyl group, etc.). good too. Examples of the aryl group having such a substituent include methylphenyl group, ethylphenyl group, dimethylphenyl group and the like.

Among these, R is preferably a linear or branched saturated or unsaturated aliphatic hydrocarbon group, more preferably a linear or branched alkyl group or alkenyl group, still more preferably It is a straight-chain alkyl group or straight-chain alkenyl group, more preferably a straight-chain alkenyl group.
In addition, the number of carbon atoms in R is preferably 1 or more, more preferably 3 or more, still more preferably 5 or more, still more preferably 6 or more, still more preferably from the viewpoint of making a metal working fluid that effectively suppresses demulsification. is 8 or more, more preferably 9 or more, particularly preferably 10 or more, and may be 11 or more, 12 or more, 13 or more, 14 or more, or 15 or more.
In addition, the number of carbon atoms in R is preferably 50 or less, more preferably 45 or less, still more preferably 40 or less, still more preferably 35 or less, particularly preferably 30 or less, and 29 or less, 28 or less, or 27 or less. , 26 or less, or 25 or less.

In one aspect of the present invention, the ether carboxylic acid (B) is, in the general formula (b-1),
A is one or more groups selected from an ethylene group and a propylene group (preferably at least containing an ethylene group, more preferably all being ethylene groups);
B is a linear alkylene group having 1 to 3 carbon atoms (preferably a methylene group),
n is an integer of 6 to 10 (preferably 8 to 10, more preferably 9 to 10, still more preferably 10),
R is a hydrocarbon group having 10 to 30 carbon atoms (preferably a linear or branched alkyl or alkenyl group having 10 to 30 carbon atoms, more preferably a linear alkenyl group having 10 to 30 carbon atoms and more preferably oleyl group).

In one aspect of the present invention, the HLB of ethercarboxylic acid (B) is 5.0 or higher. By using the ether carboxylic acid (B) having an HLB within the above range, demulsification of the metal working fluid can be suppressed. In another aspect of the invention, the HLB of ethercarboxylic acid (B) is greater than 6.0. By using the ether carboxylic acid (B) having an HLB within the above range, demulsification of the metal working fluid can be more effectively suppressed.
In one aspect of the present invention, the lower limit of HLB of the ether carboxylic acid (B) is 6.5 or more from the viewpoint of a water-soluble metal working fluid capable of becoming a metal working fluid with improved emulsion stability and workability. , 7.0 or more, 7.5 or more, 8.0 or more, 8.5 or more, 9.0 or more, 9.5 or more, 10.0 or more, 10.5 or more, or 11.0 or more 12.0 or more is particularly preferable. The upper limit of HLB of the ether carboxylic acid (B) is not particularly limited, but is 20.0 or less, 19.0 or less, 18.0 or less, 17.0 or less, 16.0 or less, 15.0 or less, Alternatively, it is 14.0 or less, and particularly preferably 13.0 or less.
In the present specification, HLB is an abbreviation for Hydrophile-lipophile balance, and is an index indicating the balance between hydrophilic groups and lipophilic groups in the surfactant molecule. As used herein, HLB refers to a value calculated by the Griffin method.

In one aspect of the present invention, the content of the ether carboxylic acid (B) is preferably based on the total amount (100% by mass) of the water-soluble metal working fluid, from the viewpoint of obtaining a metal working fluid that effectively suppresses demulsification. is 0.1% by mass or more, more preferably 0.2% by mass or more, still more preferably 0.3% by mass or more, even more preferably 0.4% by mass or more, and particularly preferably 0.5% by mass or more. , 0.7% by mass or more, 0.9% by mass or more, 1.0% by mass or more, 1.5% by mass or more, or 2.0% by mass or more.
In addition, the content of the ethercarboxylic acid (B) is preferably 12% by mass or less based on the total amount (100% by mass) of the water-soluble metalworking fluid, from the viewpoint of achieving both stability and workability of the metalworking fluid. More preferably 10% by mass or less, still more preferably 8% by mass or less, even more preferably 6% by mass or less, particularly preferably 4% by mass or less, and 3.5% by mass or less, 3% by mass or less, or , 2.5% by mass or less.

<Component (C): nonionic surfactant>
It is preferable that the water-soluble metalworking fluid of one aspect of the present invention further contain a nonionic surfactant (C). By containing the nonionic surfactant (C), it is possible to obtain a water-soluble metalworking fluid capable of becoming a metalworking fluid with improved emulsion stability and workability.
In addition, in one aspect of the present invention, the nonionic surfactant (C) may be used alone or in combination of two or more.

From the above viewpoint, in one aspect of the present invention, the content of the nonionic surfactant (C) is preferably 0.1 to 15.0 mass based on the total amount (100 mass%) of the water-soluble metalworking fluid. %, more preferably 0.2 to 10.0 mass %, still more preferably 0.3 to 8.0 mass %, even more preferably 0.5 to 6.0 mass %, particularly preferably 0.7 to 4 0% by mass, and may be 0.9% by mass or more, 1.0% by mass or more, or 1.2% by mass or more, and 3.8% by mass or less, 3.5% by mass or less, It may be 3.2% by mass or less, 3.0% by mass or less, 2.8% by mass or less, or 2.5% by mass or less.

The HLB of the nonionic surfactant (C) used in one aspect of the present invention is preferably 6.0 from the viewpoint of making it a water-soluble metalworking fluid capable of becoming a metalworking fluid with improved emulsion stability and workability. Above, more preferably 7.0 or more, still more preferably 8.0 or more, even more preferably 9.0 or more, and particularly preferably 10.0 or more.
The HLB of the nonionic surfactant (C) is 18.0 or less, preferably 17.0 or less, more preferably 16.0 or less, still more preferably 15.0 or less, and particularly preferably 14.5. It is below.

Examples of the nonionic surfactant (C) used in one aspect of the present invention include alkylene glycol, polyoxyalkylene glycol, polyoxyalkylene alkyl ether, polyoxyalkylene aryl ether, alkylphenol ethylene oxide adduct, and higher alcohol ethylene oxide adduct. , polyoxyalkylene fatty acid esters, fatty acid esters of glycerin and pentaerythritol, fatty acid esters of sucrose, fatty acid esters of polyoxyalkylene adducts of polyhydric alcohols, alkylpolyglycosides, fatty acid alkanolamides, and the like.

Among these, the nonionic surfactant (C) used in one embodiment of the present invention is a polyoxyalkylene from the viewpoint of a water-soluble metalworking fluid that can be a metalworking fluid with improved emulsion stability and workability. It preferably contains an alkyl ether.
The content of the polyoxyalkylene alkyl ether is preferably 50 to 100% by mass, more preferably 70 to 100% by mass, based on the total amount (100% by mass) of the nonionic surfactant (C) contained in the water-soluble metalworking fluid. % by mass, more preferably 80 to 100% by mass, even more preferably 90 to 100% by mass, particularly preferably 95 to 100% by mass.

<Component (D): Amine compound>
It is preferable that the water-soluble metalworking fluid of one aspect of the present invention further contain an amine compound (D). A water-soluble metalworking fluid containing an amine compound (D) improves the emulsified state and further improves antibacterial properties, anticorrosion properties, workability, etc. when mixed with dilution water to form a metalworking fluid. metal working fluid.
In addition, in the water-soluble metalworking fluid of one embodiment of the present invention, the amine compound (D) may be used singly or in combination of two or more.

From the above viewpoint, in one aspect of the present invention, the content of the amine compound (D) is preferably 2 to 40% by mass, more preferably 4 to 40% by mass, based on the total amount (100% by mass) of the water-soluble metalworking fluid. 35% by mass, more preferably 6 to 30% by mass, even more preferably 8 to 25% by mass, particularly preferably 10 to 20% by mass.

The amine compound (D) used in one embodiment of the present invention includes a monoamine having one amino nitrogen atom in one molecule, a diamine having two amino nitrogen atoms in one molecule, and an amino nitrogen atom in one molecule. Any polyamine having three or more may be used.
However, the amine compound (D) used in one aspect of the present invention contains a monoamine from the viewpoint of a water-soluble metal working fluid that can be a metal working fluid with improved antibacterial properties, rust resistance, workability, etc. is preferred.
The monoamine content is preferably 50 to 100% by mass, more preferably 60 to 100% by mass, and more preferably 70% by mass, based on the total amount (100% by mass) of the amine compound (D) contained in the water-soluble metalworking fluid. ~100% by mass, more preferably 80 to 100% by mass, more preferably 80 to 100% by mass, still more preferably 85 to 100% by mass, even more preferably 90 to 100% by mass, still more preferably 95 to 100% by mass %, particularly preferably 98 to 100% by weight.

The monoamine used as the amine compound (D) in one aspect of the present invention includes, depending on the number of substituents R, a primary monoamine represented by the following formula (i) and a secondary monoamine represented by the following formula (ii). They are classified into monoamines and tertiary monoamines represented by the following formula (iii).
It should be noted that, when the dilution water is blended into a metal working fluid, the emulsified state is improved, and the water-soluble metal working oil can be a metal working fluid with improved antibacterial properties, anti-corrosion properties, workability, etc. From the viewpoint, the amine compound (D) used in one aspect of the present invention preferably contains at least a tertiary monoamine, and more preferably contains at least one of a primary monoamine and a secondary monoamine and a tertiary monoamine. More preferably, it contains all primary monoamines, secondary monoamines, and tertiary monoamines.

In the above formula, each R independently represents a substituent. A plurality of R may be the same or different from each other. Examples of the substituent include an alkyl group, an alkyl group having a hydroxyl group, an alkenyl group, a cycloalkyl group, a phenyl group, and a benzyl group.

Examples of the alkyl group that can be selected as the substituent R include methyl group, ethyl group, propyl group (n-propyl group, i-propyl group), butyl group (n-butyl group, i-butyl group, s -butyl group, t-butyl group), pentyl group (n-pentyl group, i-pentyl group, neopentyl group), hexyl group, heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group and the like.
The alkyl group may be a straight-chain alkyl group or a branched-chain alkyl group.
The number of carbon atoms in the alkyl group is preferably 1-30, more preferably 1-20, even more preferably 1-10, even more preferably 1-6, and particularly preferably 1-4.

Examples of the alkyl group having a hydroxyl group that can be selected as the substituent R include groups in which at least one hydrogen atom of the above alkyl group is substituted with a hydroxyl group.
The alkyl group that constitutes the group may also be a straight-chain alkyl group or a branched-chain alkyl group.
The number of carbon atoms in the alkyl group having a hydroxyl group is preferably 1-30, more preferably 1-20, even more preferably 1-10, still more preferably 1-6, and particularly preferably 2-4.

Examples of alkenyl groups that can be selected as the substituent R include ethenyl (vinyl), propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, and dodecenyl. group, tridecenyl group, tetradecenyl group, pentadecenyl group, hexadecenyl group, octadecenyl group and the like.
The alkenyl group may be a straight-chain alkenyl group or a branched-chain alkenyl group.
The alkenyl group preferably has 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, still more preferably 1 to 10 carbon atoms, still more preferably 1 to 6 carbon atoms, and particularly preferably 1 to 3 carbon atoms.

Examples of the cycloalkyl group that can be selected as the substituent R include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and an adamantyl group.

The amine compound (D) used in one aspect of the present invention improves the emulsified state and further improves the antibacterial properties, antirust properties, workability, etc. when mixed with dilution water to form a metal working liquid. From the viewpoint of making a water-soluble metalworking fluid that can be used as a metalworking fluid, it is preferable to include an alkanolamine having at least one alkyl group having a hydroxyl group.
Examples of the alkanolamine include primary alkanolamine in which R in formula (i) is an alkyl group having a hydroxyl group, and secondary alkanol in which at least one of R in formula (ii) is an alkyl group having a hydroxyl group. Amines and tertiary alkanolamines in which at least one of R in the formula (iii) is an alkyl group having a hydroxyl group are included.

Examples of primary alkanolamine include ethanolamine, propanolamine, butanolamine, 2-amino-2-methyl-1-propanol and the like.

Secondary alkanolamines include, for example, N-methylethanolamine, N-ethylethanolamine, N-propylethanolamine, N-butylethanolamine, N-octylethanolamine, N-stearylethanolamine, N-oleylethanol amines, monoethanolamines such as N-cyclohexylethanolamine, N-phenylethanolamine, N-benzylethanolamine; N-methylpropanolamine, N-ethylpropanolamine, N-propylpropanolamine, N-butylpropanolamine, N -monopropanolamine such as octylpropanolamine, N-stearylpropanolamine, N-oleylpropanolamine, N-cyclohexylpropanolamine, N-phenylpropanolamine and N-benzylpropanolamine; diethanolamine, dipropanolamine and the like.

Tertiary alkanolamines include, for example, N-dimethylethanolamine, N-diethylethanolamine, N-dipropylethanolamine, N-dibutylethanolamine, N-dioctylethanolamine, N-distearylethanolamine, N- Monoethanolamines such as dioleylethanolamine, N-dicyclohexylethanolamine, N-diphenylethanolamine, N-dibenzylethanolamine; N-dimethylpropanolamine, N-diethylpropanolamine, N-dipropylpropanolamine, N- monopropanolamine such as dibutylpropanolamine, N-dioctylpropanolamine, N-distearylpropanolamine, N-dioleylpropanolamine, N-dicyclohexylpropanolamine, N-diphenylpropanolamine, N-dibenzylpropanolamine; diethanolamines such as methyldiethanolamine, N-ethyldiethanolamine, N-propyldiethanolamine, N-butyldiethanolamine, N-octyldiethanolamine, N-stearyldiethanolamine, N-oleyldiethanolamine, N-cyclohexyldiethanolamine, N-phenyldiethanolamine, N-benzyldiethanolamine; ; N-methyldipropanolamine, N-ethyldipropanolamine, N-propyldipropanolamine, N-butyldipropanolamine, N-octyldipropanolamine, N-stearyldipropanolamine, N-oleyldipropanolamine, Dipropanolamine such as N-cyclohexyldipropanolamine, N-phenyldipropanolamine, N-benzyldipropanolamine; triethanolamine, tripropanolamine (such as triisopropanolamine);

Among these, a water-soluble metalworking fluid that can be made into a metalworking fluid with good emulsification and improved antibacterial properties, antirust properties, workability, etc. when diluted water is added to make a metalworking fluid. , the amine compound (D) used in one aspect of the present invention preferably contains at least a tertiary alkanolamine, and at least one of a primary alkanolamine and a secondary alkanolamine and a tertiary alkanol It more preferably contains an amine, and even more preferably contains all of a primary alkanolamine, a secondary alkanolamine, and a tertiary alkanolamine.

The alkanolamine content is preferably 5% by mass or more, more preferably 10% by mass or more, and more preferably 20% by mass, based on the total amount (100% by mass) of the amine compound (D) contained in the water-soluble metalworking fluid. % or more, more preferably 25% by mass or more, still more preferably 30% by mass or more, particularly preferably 35% by mass or more, and further 40% by mass or more, 42% by mass or more, 44% by mass or more, 46% by mass Above, 48% by mass or more, 50% by mass or more, 55% by mass or more, or 60% by mass or more, and 100% by mass or less, 95% by mass or less, 90% by mass or less, 85% by mass or less, 80% by mass % or less, 75 mass% or less, 70 mass% or less, 68 mass% or less, 66 mass% or less, 64 mass% or less, 62 mass% or less, 60 mass% or less, 58 mass% or less, or 55 mass% or less good.

The amine compound (D) used in one aspect of the present invention preferably contains an alicyclic amine.
The alicyclic amines include primary alicyclic amines in which R in formula (i) is a cycloalkyl group, and secondary alicyclic amines in which at least one of R in formula (ii) is a cycloalkyl group. Cyclic amines and tertiary alicyclic amines in which at least one of R in the above formula (iii) is a cycloalkyl group.

Examples of primary alicyclic amines include N-cyclohexylamine.
Examples of secondary alicyclic amines include monocyclohexylamines such as N-methylcyclohexylamine, N-ethylcyclohexylamine, N-propylcyclohexylamine, N-oleylcyclohexylamine; N-cyclohexylethanolamine, N-cyclohexyl monocyclohexylalkanolamine such as propanolamine; N-dicyclohexylamine;
Tertiary alicyclic amines include, for example, dialkylmonocyclohexylamines such as N-dimethylcyclohexylamine, N-diethylcyclohexylamine, N-dipropylcyclohexylamine, N-dioleylcyclohexylamine, N-dicyclohexylamine; - monocyclohexyldialkanolamines such as cyclohexyldiethanolamine and N-cyclohexyldipropanolamine; monoalkyldicyclohexylamines such as N-methyldicyclohexylamine, N-ethyldicyclohexylamine, N-propyldicyclohexylamine and N-oleyldicyclohexylamine; dicyclohexylalkanolamine such as dicyclohexylethanolamine and N-dicyclohexylpropanolamine; tricyclohexylamine;

Among these, a water-soluble metalworking fluid that can be made into a metalworking fluid with good emulsification and improved antibacterial properties, antirust properties, workability, etc. when diluted water is added to make a metalworking fluid. From the viewpoint of, the amine compound (D) used in one aspect of the present invention preferably contains a tertiary alicyclic amine, and two of R in the formula (iii) are cycloalkyl groups More preferably, it contains a tertiary cycloaliphatic amine.

The content of the alicyclic amine is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably, based on the total amount (100% by mass) of the amine compound (D) contained in the water-soluble metalworking fluid. 20% by mass or more, more preferably 25% by mass or more, particularly preferably 30% by mass or more, and 100% by mass or less, 95% by mass or less, 90% by mass or less, 85% by mass or less, and 80% by mass or less , 75% by mass or less, 70% by mass or less, or 65% by mass or less.

The water-soluble metalworking fluid of one embodiment of the present invention may contain amines other than alkanolamines and alicyclic amines (including diamines and polyamines) as the amine compound (D).
The content of the other amine is 0 to 50% by mass, 0 to 40% by mass, 0 to 30% by mass, based on the total amount (100% by mass) of the amine compound (D) contained in the water-soluble metal working fluid. 0-20% by mass, 0-10% by mass, 0-5.0% by mass, 0-2.0% by mass, 0-1.0% by mass, 0-0.10% by mass, 0-0.01% by mass %, 0 to 0.001 mass %, 0 to 0.0001 mass %, or 0 to 0.00001 mass %.
It may be 1.1 or less, 1.0 or less, or 0.9 or less.

<Component (E): fatty acids>
It is preferable that the water-soluble metalworking fluid of one aspect of the present invention further contain fatty acids (E).
By containing the fatty acid (E), it is possible to obtain a water-soluble metal working fluid that can be a metal working fluid with improved emulsion stability, rust resistance, workability, and the like.
In addition, in one aspect of the present invention, the fatty acids (E) may be used singly or in combination of two or more.

From the above viewpoint, in one aspect of the present invention, the content of the fatty acid (E) is preferably 3 to 60% by mass, more preferably 5 to 60% by mass, based on the total amount (100% by mass) of the water-soluble metalworking fluid. 50% by mass, more preferably 9 to 40% by mass, even more preferably 12 to 35% by mass, particularly preferably 14 to 30% by mass, and may be 15% by mass or more, or 16% by mass or more, Also, it may be 27% by mass or less, 25% by mass or less, 23% by mass or less, or 21% by mass or less.

Examples of fatty acids (E) used in one aspect of the present invention include fatty acids, hydroxy fatty acids, aliphatic dicarboxylic acids, dimer acids of fatty acids, polymerized fatty acids of hydroxy unsaturated fatty acids, and the like.

Examples of the fatty acids include octanoic acid, 2-ethylhexanoic acid, decanoic acid, neodecanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, pentadecanoic acid, heptadecanoic acid, nonadecanic acid, myristic acid, palmitic acid, stearic acid, and arachin. acid, saturated aliphatic monocarboxylic acids such as behenic acid and isostearic acid, and octenoic acid, nonenoic acid, decenoic acid, undecenoic acid, oleic acid, elaidic acid, erucic acid, nervonic acid, linoleic acid, γ-linolenic acid, Examples include unsaturated aliphatic monocarboxylic acids such as arachidonic acid, α-linolenic acid, stearidonic acid, eicosapentaenoic acid and docosahexaenoic acid.
In addition, tall oil fatty acid, soybean oil fatty acid, palm oil fatty acid, linseed oil fatty acid, rice bran oil fatty acid, cottonseed oil fatty acid, etc., which are mixtures of unsaturated fatty acids, may also be used.
The number of carbon atoms in the fatty acid is preferably 8-30, more preferably 10-25, still more preferably 10-20.

Examples of the hydroxy fatty acid include hydroxylauric acid, hydroxymyristic acid, hydroxypalmitic acid, hydroxystearic acid, hydroxyarachidic acid, hydroxybehenic acid, and hydroxyoctadecenoic acid.
The hydroxy fatty acid preferably has 8 to 30 carbon atoms, more preferably 10 to 25 carbon atoms, and still more preferably 10 to 20 carbon atoms.

Examples of the aliphatic dicarboxylic acid include sebacic acid, dodecanedioic acid, dodecylsuccinic acid, laurylsuccinic acid, stearylsuccinic acid, and isostearylsuccinic acid.
The number of carbon atoms in the aliphatic dicarboxylic acid is preferably 8-30, more preferably 10-25, still more preferably 10-20.

Examples of the hydroxyunsaturated fatty acid constituting the polymerized fatty acid of the hydroxyunsaturated fatty acid include ricinoleic acid (12-hydroxyoctadeca-9-enoic acid) and the like. Fatty acid mixtures containing ricinoleic acid such as castor oil may also be used.
As the polymerized fatty acid of the hydroxyunsaturated fatty acid, a condensed fatty acid that is a dehydration polycondensate of a hydroxyunsaturated fatty acid, or an alcoholic hydroxyl group and a monocarboxylic acid of a condensed fatty acid that is a dehydration polycondensate of a hydroxyunsaturated fatty acid. and condensed fatty acids obtained by dehydration condensation.

The acid value of the fatty acid (E) is usually 0 mgKOH/g or more, preferably 10 to 100 mgKOH/g, more preferably 10 to 100 mgKOH/g, from the viewpoint of making it a water-soluble metalworking fluid that can be a metalworking fluid with improved workability. It is preferably 20 to 90 mgKOH/g, more preferably 30 to 80 mgKOH/g.
The hydroxyl value of the fatty acid (E) is preferably 0-80 mgKOH/g, more preferably 0-60 mgKOH/g, still more preferably 0-40 mgKOH/g.
The ratio of the acid value to the hydroxyl value of the fatty acid (E) [acid value/hydroxyl value] is preferably 1.5 to 15, more preferably 2.0 to 10, and still more preferably 2.5 from the above viewpoints. ~9.5.
The saponification value of the fatty acid (E) is preferably 180-220 mgKOH/g, more preferably 190-210 mgKOH/g, still more preferably 195-205 mgKOH/g.
In the present specification, the acid value means a value measured according to JIS K2501:2003 (indicator photometric titration method), and the hydroxyl value means a value measured according to JIS K0070:1992. , saponification value means a value measured based on JIS K2503:1996.

<Various other additives>
The water-soluble metal working fluid according to one aspect of the present invention may further contain various additives other than the above components (A) to (F), if necessary, as long as the effects of the present invention are not impaired. good.
Such other various additives include, for example, anionic surfactants, cationic surfactants, extreme pressure additives, metal deactivators, emulsifying aids, antibacterial agents, antifoaming agents, and antioxidants. , oily agents, and the like.
In addition, these various additives may be used individually by 1 type, respectively, and may use 2 or more types together.

In one aspect of the present invention, the content of each of these various additives is appropriately set according to the type and function of each component. , preferably 0.01 to 20 mass %, more preferably 0.03 to 15 mass %, still more preferably 0.01 to 10 mass %.

Examples of anionic surfactants include polyoxyethylene alkyl ether carboxylic acids, polyoxyethylene alkyl ether phosphates, alkylbenzene sulfonic acids, α-olefin sulfonic acids, and salts thereof.
The acid value of the anionic surfactant is preferably 20-250 mgKOH/g, more preferably 30-200 mgKOH/g, still more preferably 40-190 mgKOH/g, still more preferably 50-180 mgKOH/g.
Examples of cationic surfactants include alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts and the like.

Examples of extreme pressure additives include chlorine-based extreme-pressure additives such as chlorinated paraffin, chlorinated fatty acids, and chlorinated fatty oils; sulfur-based extreme-pressure additives such as sulfurized olefins, sulfurized lard, alkyl polysulfides, and sulfurized fatty acids; phosphoric esters, phosphites, thiophosphates, salts thereof, phosphine-based extreme pressure additives such as tricresyl phosphate;

Examples of metal deactivators include benzotriazole, imidazoline, pyrimidine derivatives, benzothiazole derivatives and thiadiazole.

Examples of emulsifying aids include unsaturated fatty acid esters such as methyl oleate, ethyl oleate and propyl oleate.

Examples of antibacterial agents include isothiazoline compounds, triazine compounds, alkylbenzimidazole compounds, metal pyrithione salts, and the like.

Antifoaming agents include, for example, silicone antifoaming agents, fluorosilicone antifoaming agents, polyacrylates, and the like.

Examples of antioxidants include amine antioxidants such as alkylated diphenylamine, phenylnaphthylamine, and alkylated phenylnaphthylamine; butylphenol), isooctyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, n-octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, etc. phenolic antioxidant; and the like.

Examples of oily agents include alcohols such as lauryl alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol, and oleyl alcohol.

<Method for producing water-soluble metalworking fluid>
The method for producing the water-soluble metal working fluid according to one aspect of the present invention is not particularly limited, and the components (A) and (B) described above and, if necessary, components (C) to (F) and other It is preferable that the method has a step of blending various additives of. The order of blending of each component can be set appropriately.

[Form of metal working fluid]
The metalworking fluid of the present invention is obtained by using the metalworking fluid of one embodiment of the present invention as a stock solution, and adding dilution water to the metalworking fluid.
Dilution water may be, for example, distilled water, ion-exchanged water, tap water, industrial water, or the like.

The blending amount of the dilution water when preparing the metalworking fluid is more than 100 parts by mass with respect to 100 parts by mass of the total amount of the components other than water in the water-soluble metalworking fluid, but the desired dilution concentration is achieved. is preferably adjusted as appropriate.
The dilution concentration of the metalworking fluid of one aspect of the present invention is preferably 1 to 50% by volume, more preferably 3 to 40% by volume, and even more preferably 5 to 20% by volume.
In this specification, the "dilution concentration of the metal working fluid" means a value calculated from the following formula.
・"Dilution concentration of metalworking fluid (% by mass)" = [mass of metalworking fluid before dilution]/[[mass of metalworking fluid before dilution] + [mass of dilution water]] × 100

[Applications of metal working fluid]
The metalworking fluid of one preferred embodiment of the present invention can be used during metalworking with machine tools that use emulsification inhibitors. According to the metalworking fluid of one preferred aspect of the present invention, for example, even if an emulsification inhibiting substance is mixed in the cutting oil tank, demulsification of the metalworking fluid is suppressed, and deterioration of the metalworking fluid can be prevented. can.
Emulsification inhibitors include, for example, grease. The type of grease is not particularly limited, and may be soap grease or urea-based grease. Examples of soap grease include calcium soap grease, lithium soap grease, aluminum complex grease, lithium complex grease and the like.

The material to be processed using the metalworking fluid of one embodiment of the present invention is not particularly limited, but is aluminum, aluminum alloys, magnesium alloys, copper, copper alloys, iron, steel, carbon steel, cast iron, titanium, Workpieces of metals selected from the group consisting of titanium alloys, steel alloys, nickel-based alloys, niobium alloys, tantalum alloys, molybdenum alloys, tungsten alloys, stainless steels, and high manganese steels are particularly preferred.

Therefore, the present invention can also provide the following [1] and [2].
[1] A method of using the metalworking fluid of one aspect of the present invention described above for machining a workpiece made of metal.
[2] A metalworking method in which the metalworking fluid of one embodiment of the present invention is applied to process a metal workpiece.

The details of the workpieces described in [1] and [2] above are as described above.
In the above [1] and [2], examples of working of the material to be worked include cutting, grinding, punching, polishing, drawing, drawing, and rolling.
In the above method [1] and the above [2] metalworking method, the metalworking fluid is prepared by adding dilution water to the water-soluble metalworking fluid according to one aspect of the present invention described above. It is used by supplying it to the workpiece and bringing it into contact with the workpiece. The metalworking fluid lubricates between the workpiece and the working tool. Furthermore, it is also used for removing chips, preventing rust from work pieces, cooling tools and work pieces, and the like.

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited by these examples.

Examples 1-15, Comparative Examples 1-9
Various components of the types shown in Tables 1 to 3 were added and mixed in the amounts shown in Tables 1 to 3 to prepare water-soluble metal working fluids. The details of each component used in the preparation of the water-soluble metalworking fluid are as follows.

<Component (A)>
- Paraffinic mineral oil: 40°C kinematic viscosity = 7.117 mm ² /s, viscosity index = 109, paraffinic mineral oil classified into Group II of the API base oil category <Component (B)>
- Polyoxyethylene alkyl ether carboxylic acid (2EO), HLB = 6
A compound represented by formula (b-1), wherein A is an ethylene group, B is a methylene group, n is 2, and R is an oleyl group.
· Polyoxyethylene alkyl ether carboxylic acid (5EO), HLB = 9.6
A compound represented by formula (b-1), wherein A is an ethylene group, B is a methylene group, n is 5, and R is an oleyl group.
· Polyoxyethylene alkyl ether carboxylic acid (8EO), HLB = 11.7
A compound represented by formula (b-1), wherein A is an ethylene group, B is a methylene group, n is 8, and R is an oleyl group.
· Polyoxyethylene alkyl ether carboxylic acid (10EO), HLB = 12.7
A compound represented by formula (b-1), wherein A is an ethylene group, B is a methylene group, n is 10, and R is an oleyl group.
・Polyoxyethylene polyoxypropylene alkyl ether carboxylic acid, HLB=10
A compound represented by formula (b-1), wherein A is a combination of an ethylene group and a propylene group, B is a methylene group, n is 3, and R is an isotridecyl group.
<Component (b')>
- Polyoxyethylene oleyl ether (10EO), HLB = 13.0
A compound of the formula (b-1) in which A is an ethylene group, B is a methylene group, n is 10, and R is an oleyl group, but does not have a carboxyl group.
<Component (C)>
- Nonionic surfactant (1): polyoxyalkylene alkyl ether, HLB = 12.7
- Nonionic surfactant (2): polyoxyalkylene alkyl ether, HLB = 8.8
<Component (D)>
Amine compound: amine mixture of monoisopropanolamine, diisopropanolamine, triisopropanolamine, and dicyclohexylamine <Component (E)>
Fatty acids: Mixed fatty acids of dodecanedioic acid, neodecanoic acid, tall oil fatty acid, and ricinoleic acid polymerized fatty acid (castor oil polymerized fatty acid), acid value = 32.3 mgKOH/g, hydroxyl value = 1.1 mgKOH/g
<Component (F)>
・Water <other ingredients>
・Metal deactivator: benzotriazole, phosphoric acid corrosion inhibitor ・Emulsifying aid: methyl oleate ・Antibacterial agent: 1,2-benzisothiazolin-3-one ・Antifoaming agent: silicone antifoaming agent

Next, using the prepared water-soluble metalworking fluid, the emulsification stability of the metalworking fluid was evaluated. First, the water-soluble metal working fluid was diluted to 20% by volume with water adjusted to a magnesium concentration of 500 ppm to prepare a metal working fluid. To 50 mL of this metal working fluid, 2.5 g of lithium complex grease (Daphne Eponex SR, manufactured by Idemitsu Kosan Co., Ltd.) was added and allowed to stand in a constant temperature bath at 60 ° C. until emulsification of the metal working fluid occurred. Measured the number of days. Demulsification was visually observed, and when separation of the oil layer and the water layer was confirmed, it was determined that emulsification had occurred. Results are shown in Tables 1 and 2.

As can be seen from Tables 1 and 2, the water-soluble metal working fluids of Examples 1 to 15 took 2 days or longer to cause emulsification failure, and had good emulsification stability even when mixed with grease. On the other hand, from Table 3, the water-soluble metal working fluids of Comparative Examples 1 to 9, which did not contain the component (B) ether carboxylic acid, all took 1 day until demulsification occurred. ), resulting in inferior emulsification stability.

Claims (14)

A water-soluble metalworking fluid containing a base oil (A) and an ether carboxylic acid (B) represented by the following general formula (b-1),
A water-soluble metalworking fluid having an ethercarboxylic acid (B) content of 0.1 to 10% by mass based on the total amount of the water-soluble metalworking fluid.

[In the formula,
A is an alkylene group having 1 to 4 carbon atoms, and when there are a plurality of A's, the plurality of A's may be the same group or different groups.
B is a single bond or an alkylene group having 1 to 4 carbon atoms,
n is an integer from 1 to 100,
R is a hydrocarbon group. ] 2. The water-soluble metalworking fluid according to claim 1, wherein B in said general formula (b-1) is a methylene group. 3. The water-soluble metalworking fluid according to claim 1, wherein the ether carboxylic acid (B) has an HLB of 5.0 or more. 3. The water-soluble metalworking fluid according to claim 1, wherein the ether carboxylic acid (B) has an HLB of more than 6.0. The water-soluble metalworking fluid according to any one of claims 1 to 4, wherein A in the general formula (b-1) is an ethylene group. The water-soluble metal working fluid according to any one of claims 1 to 4, wherein n in the general formula (b-1) is 6 or more. The water-soluble metal working fluid according to any one of claims 1 to 6, wherein R in the general formula (b-1) is a hydrocarbon group having 10 to 30 carbon atoms. The water-soluble metal working fluid according to any one of claims 1 to 7, further comprising a nonionic surfactant (C). The water solution according to claim 8, wherein the content ratio [(C)/(B)] of the nonionic surfactant (C) and the ether carboxylic acid (B) is 1 to 25 in mass ratio. anti-corrosive metalworking fluid. The water-soluble metalworking fluid according to any one of claims 1 to 9, further comprising an amine compound (D). The water-soluble metal working fluid according to claim 10, wherein the content ratio [(D)/(B)] of the amine compound (D) and the ether carboxylic acid (B) is 1 to 166 by mass. . A metalworking fluid obtained by diluting the water-soluble metalworking fluid according to any one of claims 1 to 11. 13. The metal working fluid according to claim 12, which is used during metal working by machine tools using emulsification inhibitors. 14. The metalworking fluid of claim 13, wherein the emulsification inhibitor is grease.