Processing fluid, composition for processing fluid, and composition for processing brittle materials

Abstract

To provide a working fluid excellent in lubricity, antifoaming properties and cleanability.SOLUTION: A working fluid comprises: a specific content of a component (A); a specific content of a component (B); a specific content of a component (C); a component (D); and water, wherein the component (A) is a compound that has a cloud point of a 1 mass% aqueous solution of 20°C or higher and 50°C or lower, contains a copolymerization site of an ethylene oxide and an alkylene oxide other than the ethylene oxide, and has no acetylene group, the component (B) is a compound that has a cloud point of a 1 mass% aqueous solution of above 50°C and 80°C or less, contains the copolymerization site of an ethylene oxide and an alkylene oxide other than the ethylene oxide, and has no acetylene group, and the component (C) is one or more selected from a group consisting of acetylene glycol having a HLB value of 4 or more to 12 or less and alkylene oxide adducts of acetylene glycol having a HLB value of 4 or more to 12 or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a working fluid, a working fluid composition, and a brittle material working fluid composition. [Background technology]

[0002] In the manufacture of semiconductor products, it is important to accurately cut silicon ingots, which are brittle materials. From the viewpoints of processing accuracy and productivity, wire sawing is generally used in cutting silicon ingots. Wire sawing is also used to process materials such as ceramics, quartz, sapphire, and glass. Generally, processing methods using a wire saw include the free abrasive method, in which processing is performed while supplying free abrasive grains to the sliding area between the wire and the workpiece, and the fixed abrasive method, in which processing is performed using a wire with abrasive grains previously fixed to its surface. In addition, in both types of wire saw processing, a processing fluid (coolant) is used for the purposes of improving efficiency during cutting, suppressing friction between the workpiece and the tool used to process it, reducing frictional heat generated during processing, extending the life of the tools, and removing cutting chips. Machining fluids used for the above-mentioned applications include oil-based machining fluids whose main components are mineral oils, animal and vegetable oils, synthetic oils, etc., and water-based machining fluids that are made water-soluble by blending with compounds having surface-active properties. In recent years, water-soluble machining fluids have come to be used from the viewpoints of safety during work and environmental issues.

[0003] For example, Patent Document 1 discloses a water-soluble cutting fluid for slicing silicon ingots, characterized in that it contains, as essential components, a polyoxyalkylene adduct having a number average molecular weight of 500 or less and a specific structure, and a monovalent or divalent aliphatic carboxylic acid or a salt thereof having 4 to 10 carbon atoms (including the carbon of the carbonyl group). Patent Document 2 discloses a water-soluble machining fluid composition for a fixed abrasive wire saw used to cut rare earth magnets, characterized in that the composition contains specific amounts of glycols, carboxylic acids, a compound that dissolves in water and exhibits basicity, and water (however, the total of these components is 100 parts by weight). Patent Document 3 discloses a brittle material processing fluid containing at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, a nonionic surfactant having an HLB value of 6 or more and an ethylene oxide adduct having 5 or more moles of ethylene oxide added in the molecular structure, and having no acetylene group, and a carboxylic acid, each in a specific content. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-68884 A [Patent Document 2] JP 2003-82335 A [Patent Document 3] JP 2018-154762 A Summary of the Invention [Problem to be solved by the invention]

[0005] In general, in both of the above-mentioned wire saw processing methods, a multi-wire saw device is used to cut out a plurality of silicon wafers from the above-mentioned silicon ingot at once. In the multi-wire saw device, a wire is wound around each groove on two or more guide rollers on which a plurality of grooves are carved at regular intervals, and each wire is held in parallel with a certain tension. During cutting, each guide roller is rotated, and the wire is made to travel in one or both directions while a processing fluid discharged from a nozzle or the like is applied to the wire, and the silicon ingot is pressed against the wire to which the processing fluid is applied to cut it. The machining fluid used in the wire saw processing is put into a tank equipped in the wire saw device, and is supplied from the tank to a processing chamber nozzle by a pump equipped in the wire saw device, and discharged from the nozzle. The machining fluid discharged from the nozzle is supplied to the processing gap (the gap between the wire and the silicon ingot) and is used for lubrication of the processing gap, etc., before returning to the tank. In this way, the machining fluid circulates inside the wire saw device while the silicon ingot is being cut. During the cutting process, the machining fluid may be violently scattered due to the high speed rotation of the guide rollers accompanying the high wire speed, leading to foaming of the machining fluid. In addition, during the cutting process, the machining fluid may flow down into a tank located at the bottom of the wire saw device, causing the machining fluid in the tank to foam violently and overflow from the tank. Furthermore, there are problems in that fine cutting chips generated during the cutting process promote foaming of the machining fluid, and the wire saw and cut wafers are significantly contaminated by the cutting chips, resulting in a large load to clean them. Furthermore, for example, in recent years, in the field of producing silicon wafers from the aforementioned silicon ingots, there has been a demand for further improvements in productivity, and the fixed abrasive method has come to be used frequently for reasons such as the fact that it is possible to cut in a shorter time than with the free abrasive method and that it is possible to improve yields by using thinner wire tools.

[0006] Thus, in addition to the conventional requirement of a machining fluid having an appropriate lubricity, if the machining fluid can suppress foaming and improve the cleanliness of cutting chips when used, it will lead to more stable production and improved machining accuracy. Also, as mentioned above, in recent years, there has been a demand for machining fluids that are water-soluble. Therefore, there is a demand for machining fluids that have a better balance of lubrication, antifoaming properties, and cleanliness properties.

[0007] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a machining fluid that is excellent in lubricity, antifoaming properties and cleanability. [Means for solving the problem]

[0008] As a result of intensive research, the present inventors have found that a machining fluid containing water and specific components, with the content of each component falling within a specific range, can solve the above-mentioned problems. Each embodiment of the present invention has been completed based on this finding. That is, each embodiment of the present invention provides the following [1] to

[17] . [1] Component (A): a compound having a cloud point of 20°C or more and 50°C or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Ingredient (D): Water A machining fluid comprising: The content of component (A) is 0.010% by mass or more based on 100% by mass of the total amount of the processing fluid, The content of component (B) is 0.005% by mass or more and 0.090% by mass or less based on 100% by mass of the total amount of the processing fluid, and The content of component (C) is 0.006% by mass or more based on 100% by mass of the total amount of the processing fluid; Processing fluid. [2] The processing fluid according to [1] above, wherein the content of component (A) is 0.200 mass% or less based on 100 mass% of the total amount of the processing fluid. [3] The processing fluid according to [1] or [2] above, wherein the content of component (C) is 0.100 mass% or less based on 100 mass% of the total amount of the processing fluid. [4] The processing fluid according to any one of the above [1] to [3], wherein component (A) is a compound having a cloud point of 20°C or more and 50°C or less in a 1% by mass aqueous solution, containing a copolymerization portion of ethylene oxide and propylene oxide, and having no acetylene group. [5] The processing fluid according to any one of the above [1] to [4], wherein component (B) is a compound having a cloud point of more than 50°C and not more than 80°C in a 1% by mass aqueous solution, containing a copolymerization portion of ethylene oxide and propylene oxide, and having no acetylene group. [6] The processing fluid according to any one of the items [1] to [5], wherein the ratio of the content of the component (A) to the content of the component (B) [(A) / (B)] is 1.00 or more in terms of mass ratio. [7] The processing fluid according to any one of the items [1] to [6], wherein the ratio of the total content of the components (A) and (B) to the content of the component (C) [(A)+(B) / (C)] is 1.00 or more in terms of mass ratio. [8] The machining fluid according to any one of the above [1] to [7], wherein the content of component (D) is 95.000 mass% or more and 99.979 mass% or less, based on 100 mass% of the total amount of the machining fluid. [9] The machining fluid according to any one of [1] to [8] above, having a pH of 3.0 or more and 9.0 or less.

[10] The machining fluid according to any one of the above [1] to [9], which is used when machining a workpiece made of a brittle material using a wire.

[11] The machining fluid according to

[10] , wherein the wire is a fixed abrasive wire.

[12] The machining fluid according to

[10] or

[11] , wherein the brittle material is crystalline silicon, sapphire, silicon carbide, gallium nitride, neodymium magnet, quartz crystal, or glass.

[13] At the very least, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Ingredient (D): Water A method for producing a processing fluid, comprising: The content of component (A) is 0.010% by mass or more based on 100% by mass of the total amount of the processing fluid, The content of component (B) is 0.005% by mass or more and 0.090% by mass or less based on 100% by mass of the total amount of the processing fluid, and The content of component (C) is 0.006% by mass or more based on 100% by mass of the total amount of the processing fluid, The method for producing a working fluid according to any one of the above [1] to

[12] , wherein the working fluid is obtained by blending the components so as to satisfy the following formula:

[14] Component (A): a compound having a cloud point of 20°C or more and 50°C or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Ingredient (D): Water A composition for a machining fluid comprising: The content of component (A) is 0.200% by mass or more based on the total amount (100% by mass) of the composition for machining fluid; The content of component (B) is 0.100 mass% or more and 92.000 mass% or less based on the total amount of the composition for machining fluid (100 mass%), and The content of component (C) is 0.120% by mass or more based on the total amount (100% by mass) of the composition for processing fluid; Composition for processing fluid.

[15] At the very least, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Ingredient (D): Water A method for producing a composition for a machining fluid, comprising: The content of component (A) is 0.200% by mass or more based on the total amount (100% by mass) of the composition for machining fluid; The content of component (B) is 0.100 mass% or more and 92.000 mass% or less based on the total amount of the composition for machining fluid (100 mass%), and The content of component (C) is 0.120% by mass or more based on 100% by mass of the total amount of the composition for machining fluid; The method for producing a composition for working fluid for brittle materials according to the above

[14] , wherein the components are mixed so as to obtain a composition for working fluid.

[16] A brittle material processing fluid composition comprising an additive mixture containing the following components (A) to (C), and component (D): water, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): one or more selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less; In the additive mixture, The content of component (A) is 20.00% by mass or more based on the total amount of the additive mixture (100% by mass), The content of component (B) is 5.00% by mass or more and 53.50% by mass or less based on the total amount of the additive mixture (100% by mass), and The content of component (C) is 5.00% by mass or more based on the total amount of the additive mixture (100% by mass). Brittle material processing fluid composition.

[17] A method for producing a brittle material processing fluid composition, comprising blending an additive mixture containing at least the following components (A) to (C), and component (D): water, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): one or more selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less; In the additive mixture, The content of component (A) is 20.00% by mass or more based on the total amount of the additive mixture (100% by mass), The content of component (B) is 5.00% by mass or more and 53.50% by mass or less based on the total amount of the additive mixture (100% by mass), and The content of component (C) is 5.00% by mass or more based on 100% by mass of the total amount of the additive mixture; The method for producing a brittle material processing fluid composition according to the above

[16] , Effect of the Invention

[0009] According to the present invention, it is possible to provide a machining fluid having excellent lubricity, antifoaming properties and cleanability. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [Processing fluid] The working fluid according to one embodiment of the present invention is Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Component (D): A processing fluid containing water, The content of component (A) is 0.010% by mass or more based on 100% by mass of the total amount of the processing fluid, The content of component (B) is 0.005% by mass or more and 0.090% by mass or less based on 100% by mass of the total amount of the processing fluid, and The content of component (C) is 0.006% by mass or more based on 100% by mass of the total amount of the processing fluid. A machining fluid that satisfies all of the above-mentioned requirements has an excellent balance of lubrication, antifoaming properties, and detergency.

[0011] In this specification, unless otherwise specified, "alkylene oxide (hereinafter, also simply referred to as "AO") adduct" includes not only a compound to which a single alkylene oxide is added, but also a compound to which multiple alkylene oxides, i.e., polyalkylene oxides, are added. Hereinafter, the same applies to "ethylene oxide (hereinafter, also simply referred to as "EO") adduct" and "propylene oxide (hereinafter, also simply referred to as "PO") adduct". Furthermore, the term "HLB value" used herein means the HLB (Hydrophilic-Lipophilic Balance) value calculated by the Griffin method. In this specification, the lower limit and upper limit described in stages for the preferred numerical range (e.g., range of content, etc.) can be independently combined. For example, the lower limit of the corresponding numerical range is "preferably 10 or more, more preferably 20 or more, and even more preferably 30 or more," and the lower limit is "preferably 90 or less, more preferably 80 or less, and even more preferably 60 or less." The preferred range can be set to "10 or more, 60 or less" by combining the "preferred lower limit (10)" and the "more preferred upper limit (60)." Similarly, the preferred range can be set to "30 or more, 90 or less" by combining the "more preferred lower limit (30)" and the "preferred upper limit (90)." Similarly, for example, a description of "preferably 10 to 90, more preferably 20 to 80, and even more preferably 30 to 60" can also be changed to "10 to 60" or "30 to 90." Unless otherwise specified, when a preferred numerical range is simply described as "10 to 90", it indicates a range of 10 or more and 90 or less. Similarly, the numerical range to be satisfied can be combined with each of the stepwise described preferred numerical ranges. For example, when the numerical range to be satisfied is 5 or more and 100 or less, the lower limit value to be satisfied "5" can be combined with the above-mentioned "more preferable upper limit value (60)" to set the preferred range to "5 or more and 60 or less". Similarly, the "preferable lower limit value (10)" can be combined with the upper limit value to be satisfied "100" to set the preferred range to "10 or more and 100 or less". As for the combination of these numerical ranges to be satisfied and preferred numerical ranges, similar to the combination of the above-mentioned preferred numerical ranges, the numerical ranges and preferred numerical ranges can be similarly combined when they are simply described as "5 to 100" and "preferably 10 to 90". Each component contained in the machining fluid will be described below.

[0012] <Component (A)> Component (A) is a compound having a cloud point of 20°C or more and 50°C or less in a 1% by mass aqueous solution, which contains a copolymerization portion of ethylene oxide and an alkylene oxide other than ethylene oxide, and which has no acetylene groups, and is preferably a compound having a cloud point of 20°C or more and 50°C or less in a 1% by mass aqueous solution, which contains a copolymerization portion of ethylene oxide and propylene oxide, and which has no acetylene groups. If the cloud point of a 1% by mass aqueous solution of component (A) is less than 20° C., the solubility of component (A) in water decreases. On the other hand, a 1% by mass aqueous solution of component (A) having a cloud point of more than 50° C. and not more than 80° C. corresponds to component (B) described below, but if the working fluid does not contain component (A), the lubricity of the working fluid decreases. Therefore, from the viewpoint of obtaining a working fluid having excellent lubricity, the cloud point of a 1% by mass aqueous solution of component (A) is preferably 22°C or higher, more preferably 25°C or higher, even more preferably 30°C or higher, still more preferably 35°C or higher, and preferably 49°C or lower, more preferably 48°C or lower, even more preferably 47°C or lower, and still more preferably 46°C or lower. The cloud point of a 1% by mass aqueous solution of component (A) is a value measured using the method described in the examples described below.

[0013] Examples of the compound of component (A) which contains a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide and has no acetylene group include one or more members selected from the group consisting of a copolymer of EO and an AO other than EO, and polyoxyethylene alkylene alkyl ethers.

[0014] The copolymer of EO and AO other than EO related to component (A) is a copolymer of EO and an AO other than EO described below, and the mode of addition of the EO and the AO other than EO may be either random addition or block addition, or may be a mixture of random addition and block addition, but is preferably a block addition copolymer. Examples of AO other than EO in the component (A) include alkylene oxides having 3 or 4 carbon atoms, such as propylene oxide (PO), oxetane, 1,2-butylene oxide, 2,3-butylene oxide, 1,3-butylene oxide, and tetrahydrofuran. The copolymer of EO and AO other than EO related to component (A) is more preferably a copolymer of EO and PO, even more preferably a block copolymer of EO and PO (also referred to as a "block copolymer having polyethylene glycol units and polypropylene glycol units"), and even more preferably a triblock copolymer of EO and PO (also referred to as a "triblock copolymer having polyethylene glycol units and polypropylene glycol units"). In addition, the triblock copolymer of EO and PO may be a triblock copolymer (EO / PO / EO type) in which the terminal blocks are composed of EO and the intermediate block is composed of PO, or a triblock copolymer (so-called reverse type, PO / EO / PO type) in which the terminal blocks are composed of PO and the intermediate block is composed of EO.

[0015] Examples of the polyoxyethylene alkylene alkyl ether related to component (A) include EO and AO adducts other than EO of alcohols, and EO and PO adducts of alcohols are preferred. Examples of the alcohol include aliphatic alcohols having a carbon number of 1 to 24. From the viewpoint of the balance between hydrophilicity and lipophilicity, the carbon number of the alcohol is preferably 1 to 14, more preferably 1 to 10, even more preferably 1 to 6, still more preferably 1 to 4, still more preferably 1 or 2, and still more preferably 1. The aliphatic alcohol is preferably a primary alcohol or a secondary alcohol, more preferably a primary alcohol, and may be linear, branched, or cyclic, preferably linear. Examples of the aliphatic alcohol include methanol, ethanol, propanol, isopropanol, butanol, isobutanol, 2-methyl-2-butanol, pentanol, isopentanol, hexanol, 3-methyl-1-pentanol, heptanol, 2-heptanol, 3-heptanol, octanol, 2-ethylhexanol, nonanol, decanol, undecyl alcohol, lauryl alcohol, tridecyl alcohol, isotridecyl alcohol, myristyl alcohol, pentadecyl alcohol, palmityl alcohol, heptadecanol, and stearyl. Examples of such alcohols include saturated aliphatic alcohols such as ethylcyclohexyl alcohol, propylcyclohexyl alcohol, octylcyclohexyl alcohol, nonadecyl alcohol, and eicosanol; unsaturated aliphatic alcohols such as octenyl alcohol, decenyl alcohol, dodecenyl alcohol, tridecenyl alcohol, tetradecenyl alcohol, palmitoleyl alcohol, oleyl alcohol, gadoleyl alcohol, and linoleyl alcohol; and cyclic aliphatic alcohols such as ethylcyclohexyl alcohol, propylcyclohexyl alcohol, octylcyclohexyl alcohol, nonylcyclohexyl alcohol, and adamantyl alcohol.

[0016] In the polyoxyethylene alkylene alkyl ether of component (A), AO other than EO may be, for example, an alkylene oxide having 3 or 4 carbon atoms, such as propylene oxide (PO), oxetane, 1,2-butylene oxide, 2,3-butylene oxide, 1,3-butylene oxide, or tetrahydrofuran. Of these, PO is preferred. In the polyoxyethylene alkylene alkyl ether of component (A), at the copolymerization site of the EO and the AO other than EO, the addition mode of the EO and the AO other than EO may be either random addition or block addition, or a mixture of random addition and block addition may be used.

[0017] The polyoxyethylene alkylene alkyl ether can be synthesized by adding EO and AO to the alcohol. The addition of EO and AO to the alcohol can be carried out by a known method, and may be carried out in the absence or presence of a catalyst, under normal pressure or increased pressure, in one stage or in multiple stages.

[0018] In addition, in the copolymerization portion of EO and AO other than EO in component (A), the content of structural units derived from EO in 100 mol % of the total amount of structural units constituting the copolymerization portion is preferably 15 mol % or more, more preferably 20 mol % or more, even more preferably 25 mol % or more, and is preferably 85 mol % or less, more preferably 80 mol % or less, even more preferably 75 mol % or less.

[0019] From the viewpoint of improving lubricity, the mass average molecular weight (Mw) of component (A) is preferably 500 or more, more preferably 1,000 or more, even more preferably 1,500 or more, and even more preferably 2,000 or more. On the other hand, from the viewpoint of improving the bite of the abrasive grains to the workpiece, the mass average molecular weight (Mw) of component (A) is preferably 10,000 or less, more preferably 9,000 or less, even more preferably 8,000 or less, and even more preferably 6,000 or less. The value of the mass average molecular weight (Mw) is a value measured by the method described in the examples below.

[0020] The component (A) may be used alone or in combination of two or more kinds.

[0021] The content of component (A) is 0.010% by mass or more based on 100% by mass of the total amount of the working fluid. If the content is less than 0.010% by mass, the working fluid will have poor lubricity. Therefore, from the viewpoint of improving the lubricity of the working fluid, the content of component (A) is preferably 0.015 mass% or more, more preferably 0.020 mass% or more, even more preferably 0.025 mass% or more, still more preferably 0.030 mass% or more, and even more preferably 0.035 mass% or more, based on 100 mass% of the total amount of the working fluid. On the other hand, from the viewpoint of improving the defoaming properties of the processing fluid, the content of component (A) is preferably 0.200 mass% or less, more preferably 0.100 mass% or less, even more preferably 0.080 mass% or less, and still more preferably 0.075 mass% or less, based on 100 mass% of the total amount of the processing fluid.

[0022] <Ingredient (B)> Component (B) is a compound having a cloud point of more than 50°C and not more than 80°C in a 1% by mass aqueous solution, which contains a copolymerization portion of ethylene oxide and an alkylene oxide other than ethylene oxide, and which has no acetylene groups, and is preferably a compound having a cloud point of more than 50°C and not more than 80°C in a 1% by mass aqueous solution, which contains a copolymerization portion of ethylene oxide and propylene oxide, and which has no acetylene groups. The cloud point of a 1% by mass aqueous solution of component (B) having a cloud point of 50° C. or less and 20° C. or more corresponds to the above-mentioned component (A), but if the machining fluid does not contain component (B), the cleanliness of the machining fluid decreases. Therefore, from the viewpoint of obtaining a machining fluid with excellent cleanliness, the cloud point of a 1% by mass aqueous solution of component (B) is preferably 55° C. or more, more preferably 58° C. or more, and even more preferably 60° C. or more. On the other hand, if the cloud point of a 1% by mass aqueous solution of component (B) exceeds 80° C., the cleanliness of the working fluid decreases. Therefore, from the viewpoint of obtaining a working fluid with excellent cleanliness, the cloud point of a 1% by mass aqueous solution of component (B) is preferably 75° C. or lower, more preferably 70° C. or lower, and even more preferably 65° C. or lower. The cloud point of a 1% by mass aqueous solution of component (B) is a value measured using the method described in the examples below.

[0023] The compound containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide and having no acetylene group, which is the component (B), may be, for example, one or more selected from the group consisting of a copolymer of EO and an AO other than EO, or a polyoxyethylene alkylene alkyl ether. Among these, a copolymer of EO and an AO other than EO is preferred.

[0024] In the copolymer of EO and AO other than EO related to the component (B), the mode of addition of the EO and AO other than EO may be either random addition or block addition, or may be a mixture of random addition and block addition, but is preferably a block addition copolymer. Examples of AO other than EO in the component (B) include alkylene oxides having 3 or 4 carbon atoms, such as propylene oxide (PO), oxetane, 1,2-butylene oxide, 2,3-butylene oxide, 1,3-butylene oxide, and tetrahydrofuran. The copolymer of EO and an AO other than EO relating to component (B) is more preferably a copolymer of EO and PO, even more preferably a block copolymer of EO and PO, still more preferably a triblock copolymer of EO and PO, and even more preferably a Pluronic type copolymer in which ethylene oxide is added to polypropylene glycol (EO-PO-EO type triblock copolymer).

[0025] Furthermore, in the copolymer of EO and AO other than EO related to component (B), the content of structural units derived from EO in 100 mol % of the total amount of structural units constituting the copolymer is preferably 25 mol % or more, more preferably 30 mol % or more, even more preferably 35 mol % or more, still more preferably 40 mol % or more, and is preferably 75 mol % or less, more preferably 70 mol % or less, even more preferably 65 mol % or less, and still more preferably 60 mol % or less.

[0026] The polyoxyethylene alkylene alkyl ether related to component (B) is the same as that explained for the polyoxyethylene alkylene alkyl ether related to component (A), except for the difference in cloud point, and the preferred embodiments thereof are also the same.

[0027] From the viewpoint of improving lubricity, the mass average molecular weight (Mw) of component (B) is preferably 500 or more, more preferably 1,000 or more, even more preferably 1,500 or more, and even more preferably 2,000 or more. On the other hand, from the viewpoint of improving the bite of the abrasive grains into the workpiece, the mass average molecular weight (Mw) of component (B) is preferably 10,000 or less, more preferably 9,000 or less, even more preferably 8,000 or less, and even more preferably 6,000 or less. The value of the mass average molecular weight (Mw) is a value measured by the method described in the examples below.

[0028] The component (B) may be used alone or in combination of two or more kinds.

[0029] The content of component (B) is 0.005% by mass or more based on 100% by mass of the total amount of the working fluid. If the content is less than 0.005% by mass, the cleanliness of the working fluid is poor. Therefore, from the viewpoint of improving the cleanliness of the working fluid, the content of component (B) is preferably 0.010 mass% or more, more preferably 0.012 mass% or more, and even more preferably 0.015 mass% or more, based on 100 mass% of the total amount of the working fluid. On the other hand, the content of component (B) is 0.090% by mass or less based on 100% by mass of the total amount of the working fluid. If the content exceeds 0.090% by mass, the lubricity of the working fluid deteriorates. Therefore, from the viewpoint of improving the lubricity of the working fluid, the content of component (B) is preferably 0.080 mass% or less, more preferably 0.050 mass% or less, and even more preferably 0.030 mass% or less, based on 100 mass% of the total amount of the working fluid.

[0030] From the viewpoint of improving the lubricity of the working fluid, the ratio of the content of the component (A) to the content of the component (B) in the working fluid [(A) / (B)], in terms of mass ratio, is preferably 1.00 or more, more preferably 1.50 or more, and even more preferably 2.00 or more. On the other hand, from the viewpoint of improving the cleanliness of the machining fluid and machining accuracy, the ratio of the content of the component (A) to the content of the component (B) in the machining fluid [(A) / (B)], in terms of mass ratio, is preferably 20.00 or less, more preferably 15.00 or less, and even more preferably 10.00 or less.

[0031] <Component (C)> The component (C) is at least one member selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less. If the working fluid does not contain component (C), the antifoaming property and detergency of the working fluid will be deteriorated. As described above, even if component (B) is not included, the cleanliness of the machining fluid is deteriorated, but a machining fluid with good cleanliness cannot be obtained by including only one component. That is, by including both component (B) and component (C), a machining fluid with good cleanliness can be obtained. Therefore, by containing all of the components (A), (B) and (C) in specific amounts, it is possible to obtain a machining fluid that is excellent in all of lubricity, antifoaming properties and detergency properties.

[0032] Furthermore, when the HLB value of component (C) is less than 4, the solubility of component (C) in water is poor. Therefore, from the viewpoint of improving the solubility of component (C) in water, the HLB value of component (C) is preferably 5 or more, more preferably 6 or more, and even more preferably 7 or more. On the other hand, the antifoaming and cleanability of the working fluid deteriorates when the HLB value of the component (C) exceeds 12. Therefore, from the viewpoint of improving the antifoaming and cleanability of the working fluid, the HLB value of the component (C) is preferably 11 or less, more preferably 10 or less, and even more preferably 9 or less. Moreover, the HLB value of the component (C) is a value calculated by the Griffin method, as described above.

[0033] The acetylene glycol may, for example, be a compound represented by the following general formula (1).

[0034] [ka]

[0035] In general formula (1), R 1 ~R 4 each independently represents an alkyl group having 1 to 5 carbon atoms. R 1 ~R 4 Specific examples of the alkyl group having 1 to 5 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1,1-dimethylpropyl group, a 1,2-dimethylpropyl group, and a 2,2-dimethylpropyl group. Among these, R 1 and R 3 is preferably an isobutyl group or a 3-methylbutyl group. 2 and R 4 is preferably a methyl group. In addition, the compound represented by the general formula (1) is preferably R 1 and R 3and R are identical to each other, or 2 and R 4 and R are preferably the same structure. 1 and R 3 and are identical to each other, and R 2 and R 4 and are compounds having the same structure.

[0036] The alkylene oxide adduct of acetylene glycol is preferably an alkylene oxide adduct of a compound represented by general formula (1) in which AO is added to each hydroxyl group of the compound represented by general formula (1), more preferably an alkylene oxide adduct of a compound represented by general formula (1) in which EO and / or PO is added, and even more preferably an alkylene oxide adduct of a compound represented by general formula (1) in which EO is added. Note that the preferred embodiment of the acetylene glycol forming the alkylene oxide adduct of acetylene glycol is the same as the preferred embodiment of the compound represented by general formula (1) described above. In addition, when the polymer contains a structure in which a structure derived from EO (e.g., an ethyleneoxy group or a poly(oxyethylene) structure) and a structure derived from PO (e.g., a propyleneoxy group or a poly(oxypropylene) structure) are bonded together, the respective structures may be bonded to each other in a random type or in a block type, and are preferably bonded to each other in a block type.

[0037] Examples of the component (C) include acetylene glycols represented by the general formula (1), such as 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol, 5,8-dimethyl-6-dodecyne-5,8-diol, 2,4,7,9-tetramethyl-5-dodecyne-4,7-diol, 8-hexadecyne-7,10-diol, 7-tetradecyne-6,9-diol, 2,3,6,7-tetramethyl-4-octyne-3,6-diol, 3,6-diethyl-4-octyne-3,6-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 2,4,7,9-tetramethyl-5-decyne-4,7-diol, and 3,6-dimethyl-4-octyne-3,6-diol; and alkylene oxide adducts of acetylene glycol represented by the general formula (1). The alkylene oxide includes EO and / or PO. Among these, preferred are 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol, 5,8-dimethyl-6-dodecyne-5,8-diol, 2,4,7,9-tetramethyl-5-dodecyne-4,7-diol, 8-hexadecyne-7,10-diol, 7-tetradecyne-6,9-diol, 2,3,6,7-tetramethyl-4-octyne-3,6-diol, and 3,6-diethyl-4-octyne-3,6-diol. more preferably 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol, 5,8-dimethyl-6-dodecyne-5,8-diol, 2,4,7,9-tetramethyl-5-octyne-4,7-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 2,4,7,9-tetramethyl-5-decyne-4,7-diol, and 3,6-dimethyl-4-octyne-3,6-diol; -dodecyne-4,7-diol, 8-hexadecyne-7,10-diol, 7-tetradecyne-6,9-diol, 2,3,6,7-tetramethyl-4-octyne-3,6-diol, 3,6-diethyl-4-octyne-3,6-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 2,4,7,9-tetramethyl-5-decyne-4,7-diol and 3,6-dimethyl-4-octyne-3,6-diol The ethylene oxide adduct is preferably one or more selected from the group consisting of an ethylene oxide adduct of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol and an ethylene oxide adduct of 2,4,7,9-tetramethyl-5-decyne-4,7-diol, and more preferably an ethylene oxide adduct of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol. The component (C) may be used alone or in combination of two or more kinds.

[0038] The content of component (C) is 0.006% by mass or more based on 100% by mass of the total amount of the working fluid. If the content is less than 0.006% by mass, the cleanliness of the working fluid deteriorates. From the viewpoint of obtaining excellent cleanliness of the working fluid, the content of component (C) is preferably 0.007 mass% or more, more preferably 0.008 mass% or more, and even more preferably 0.009 mass% or more, based on 100 mass% of the total amount of the working fluid. On the other hand, from the viewpoint of improving the solubility of component (C) in water, the content of component (C) is preferably 0.100 mass% or less, more preferably 0.070 mass% or less, even more preferably 0.050 mass% or less, and still more preferably 0.030 mass% or less, based on 100 mass% of the total amount of the processing fluid.

[0039] In addition, in the processing fluid, the ratio of the total content of the components (A) and (B) to the content of the component (C) [(A)+(B) / (C)], in terms of mass ratio, is preferably 1.00 or more, more preferably 1.20 or more, even more preferably 1.30 or more, and is preferably 20.00 or less, more preferably 15.00 or less, even more preferably 12.00 or less.

[0040] <Ingredient (D)> The water as component (D) is not particularly limited, and may be purified water such as distilled water or ion-exchanged water (deionized water); tap water; industrial water; or the like. Purified water is preferred, and ion-exchanged water (deionized water) is more preferred.

[0041] For example, from the viewpoint of improving the flame retardancy of the working fluid to enhance safety, and from the viewpoint of lowering the viscosity of the working fluid to improve the handling property, the content of component (D) is preferably 95.000 mass% or more, more preferably 97.500 mass% or more, even more preferably 99.500 mass% or more, and even more preferably 99.600 mass% or more based on the total amount of the working fluid (100 mass%). And, from the viewpoint of ensuring the amounts of components (A), (B) and (C) in the working fluid, the content is 99.979 mass% or less, preferably 99.965 mass% or less, more preferably 99.950 mass% or less, even more preferably 99.945 mass% or less, and even more preferably 99.930 mass% or less. In this specification, the term "mixture of additives in the working fluid" refers to all components of the working fluid except for water, which is component (D).

[0042] <Other ingredients> The working fluid may further contain other components in addition to the above-mentioned components (A) to (D) as long as the object of the present invention is not impaired. Examples of other components include additives such as surfactants other than the compounds corresponding to components (A) to (C), pH adjusters, water retention improvers, antifoaming agents, metal deactivators, bactericides / preservatives, rust inhibitors, and antioxidants. These additives may be used alone or in combination of two or more. Among these additives, preferred are one or more selected from the group consisting of surfactants other than components (A) to (C), pH adjusters, and water retention improvers, more preferred are one or more selected from the group consisting of water retention improvers and pH adjusters, and even more preferred are pH adjusters. These additives may be used alone or in combination of two or more.

[0043] Examples of the surfactant other than the compounds corresponding to components (A) to (C) include anionic surfactants, cationic surfactants, nonionic surfactants other than the compounds corresponding to components (A) to (C), and amphoteric surfactants. Examples of anionic surfactants include alkylbenzenesulfonates, alphaolefinsulfonates, etc. Examples of cationic surfactants include quaternary ammonium salts such as alkyltrimethylammonium salts, dialkyldimethylammonium salts, and alkyldimethylbenzylammonium salts. Examples of nonionic surfactants other than the compounds corresponding to components (A) to (C) include polyoxyethylene alkyl ethers; polyoxyalkylene alkyl ethers (provided that the polyoxyalkylene moiety does not include a structure derived from an ethylene oxide group); ethers such as polyoxyethylene alkyl phenyl ethers; compounds having a cloud point of less than 20°C and not less than 80°C in a 1% by mass aqueous solution, containing a copolymerization moiety of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; acetylene glycols having an HLB value of less than 4 and more than 12; alkylene oxide adducts of acetylene glycols having an HLB value of less than 4 and more than 12; and amides such as fatty acid alkanolamides. Examples of amphoteric surfactants include betaine-based alkyl betaines.

[0044] The pH adjuster is mainly used to adjust the pH of the machining fluid. Examples of the pH adjuster include various acid components and base components, and the pH of the machining fluid can be appropriately adjusted by adjusting the content ratio of these components. The acid component and the base component may react with each other to form a salt. Therefore, when an acid component and a base component are used as a pH adjuster, if a reaction product of the acid component and the base component is present in the machining fluid, the contents of the acid component and the base component that contributed to the reaction can be calculated from the contents of the reaction product of the acid component and the base component as described above. In this case, the acid component and the base component before the reaction can be regarded as being contained instead of the reaction product.

[0045] Examples of acid components used as pH adjusters include various fatty acids such as lauric acid, stearic acid, oleic acid, linoleic acid, linolenic acid, neodecanoic acid, isononanoic acid, capric acid, and isostearic acid; carboxylic acids such as acetic acid, malic acid, and citric acid; polymeric acids such as polyacrylic acid and salts thereof; and inorganic acids such as phosphoric acid. Among these, fatty acids are preferred, and fatty acids having 12 or less carbon atoms such as neodecanoic acid, isononanoic acid, capric acid, and dodecanedioic acid are more preferred, and one or more selected from the group consisting of neodecanoic acid, isononanoic acid, capric acid, and dodecanedioic acid are even more preferred.

[0046] Examples of the base component used as a pH adjuster include alkanolamines such as monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, tri-n-propanolamine, tri-n-butanolamine, triisobutanolamine, tri-tert-butanolamine, N-methylethanolamine, N-ethylethanolamine, N-butylethanolamine, N-cyclohexylethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N-cyclohexyldiethanolamine, N,N-dimethylethanolamine, and N,N-diethylethanolamine; alkylamines such as methylamine, dimethylamine, ethylamine, diethylamine, propylamine, and dipropylamine; and ammonia. Among these, tertiary amines are preferred, and at least one selected from the group consisting of triethanolamine, triisopropanolamine, N-methyldiethanolamine, and N-cyclohexyldiethanolamine is more preferred.

[0047] Examples of water retention enhancers include ethylene glycol, propylene glycol, 1,4-butanediol, hexamethylene glycol, neopentyl glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, glycerin, ester derivatives thereof, ether derivatives thereof, polyethylene glycol, polypropylene glycol, and the like. Antifoaming agents include, for example, silicone oils, fluorosilicone oils, polyether polysiloxanes, and fluoroalkyl ethers. Metal deactivators include, for example, imidazolines, pyrimidine derivatives, thiadiazoles and benzotriazoles. Examples of disinfectants and preservatives include paraoxybenzoic acid esters (parabens), as well as benzoic acid, salicylic acid, sorbic acid, dehydroacetic acid, p-toluenesulfonic acid and their salts, and phenoxyethanol. Examples of the rust inhibitor include alkylbenzene sulfonate, dinonylnaphthalene sulfonate, alkenyl succinate, and polyhydric alcohol ester. Examples of the antioxidant include phenol-based antioxidants and amine-based antioxidants.

[0048] When the processing fluid contains other components, the total content of the other components in the processing fluid is, based on 100 mass% of the total amount of the processing fluid, preferably 0.0001 mass% or more, more preferably 0.0002 mass% or more, even more preferably 0.0003 mass% or more, still more preferably 0.0004 mass% or more, and preferably 0.0800 mass% or less, more preferably 0.0500 mass% or less, even more preferably 0.0100 mass% or less, still more preferably 0.0050 mass% or less, and still more preferably 0.0010 mass% or less.

[0049] Furthermore, when the processing fluid contains a pH adjuster as another component, the total content of the pH adjuster in the processing fluid is, based on 100 mass% of the total amount of the processing fluid, preferably 0.0001 mass% or more, more preferably 0.0002 mass% or more, even more preferably 0.0003 mass% or more, and preferably 0.0100 mass% or less, more preferably 0.0050 mass% or less, even more preferably 0.0010 mass% or less, and even more preferably 0.0008 mass% or less.

[0050] Furthermore, from the viewpoint of improving lubricity, antifoaming properties and cleanability, the total content of components (A), (B), (C) and (D) in the working fluid is, based on 100 mass% of the total amount of the working fluid, preferably 99.9200 mass% or more, more preferably 99.9500 mass% or more, even more preferably 99.9900 mass% or more, still more preferably 99.9950 mass% or more, still more preferably 99.9990 mass% or more, and preferably 100.0000 mass% or less, more preferably 99.9999 mass% or less, still more preferably 99.9998 mass% or less, still more preferably 99.9997 mass% or less, and still more preferably 99.9996 mass% or less.

[0051] When the machining fluid is used for machining a brittle material, the pH of the machining fluid is preferably 3.0 or more, more preferably 4.0 or more, and even more preferably 5.0 or more, from the viewpoint of suppressing corrosion of wires, machining equipment, etc., which will be described later in the section on uses of the machining fluid. On the other hand, the pH of the machining fluid is preferably 9.0 or less, more preferably 8.0 or less, and even more preferably 7.0 or less, from the viewpoint of suppressing a large amount of hydrogen generation from cuttings when machining silicon, etc. The pH value of the machining fluid is a value measured using the method described in the examples below.

[0052] Furthermore, for example, as described below, when the machining fluid is used in an application in which a workpiece made of a brittle material is processed using a wire, from the viewpoint of making it easier to prevent wire breakage that occurs during cutting of the brittle material, the surface tension of the machining fluid is preferably 35 mN / m or less, more preferably 34 mN / m or less, and even more preferably 33 mN / m or less. On the other hand, the surface tension of the machining fluid is preferably 1 mN / m or more, more preferably 5 mN / m or more, and even more preferably 10 mN / m or more. The surface tension of the machining fluid is a value measured using the method described in the examples below.

[0053] [Method of manufacturing the machining fluid] The method for producing the machining fluid includes: At least, component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; component (B): a compound having a cloud point of 50° C. or more and 80° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Ingredient (D): Water A method for producing a processing fluid, comprising: The content of component (A) is 0.010% by mass or more based on 100% by mass of the total amount of the processing fluid, The content of component (B) is 0.005% by mass or more and 0.090% by mass or less based on 100% by mass of the total amount of the processing fluid, and The content of component (C) is 0.006% by mass or more based on 100% by mass of the total amount of the processing fluid, This is a manufacturing method for obtaining a processing fluid by mixing the above ingredients so as to obtain the processing fluid.

[0054] The order in which components (A) to (D) are mixed is not particularly limited. For example, components (A), (B) and (C) may be mixed sequentially or simultaneously with water, which is component (D). Alternatively, components (A), (B) and (C) may be mixed in advance, and the mixture may be mixed with water, which is component (D). In the production method, components (A) to (D) are blended, and other components may be blended as necessary. In this case, the order of blending the components, the blending method, etc. are not particularly limited. In addition, component (A), component (B), component (C), component (D) and other components are the same as those described above in the processing fluid section, and the preferred embodiments are also the same, so detailed explanations are omitted. In addition, the preferred amounts of component (A), component (B), component (C), component (D) and other components and the preferred ratios of the amounts of each component are the same as the respective contents and the respective content ratios in the processing fluid described above in the processing fluid section, so detailed explanations are omitted.

[0055] [Uses of machining fluid] The machining liquid can be suitably used when a workpiece made of a brittle material such as a silicon ingot is processed by wire sawing using the above-mentioned wire saw, preferably a fixed abrasive wire saw. That is, the machining liquid can be suitably used when a workpiece made of a brittle material is processed by using a wire, and can be more suitably used when a workpiece made of a brittle material is processed by using a fixed abrasive wire. Examples of the brittle material include crystalline silicon, sapphire, gallium nitride, silicon carbide, neodymium magnet, quartz, and glass. From the viewpoint of effectively utilizing the excellent cleanliness of the working fluid, the working fluid can be more suitably used when processing crystalline silicon, sapphire, silicon carbide, gallium nitride, neodymium magnet, quartz, or glass, and can be even more suitably used when processing crystalline silicon, sapphire, or silicon carbide.

[0056] [Method of processing brittle materials] A method for processing a brittle material according to one embodiment of the present invention is a method for processing a workpiece made of the brittle material, such as a silicon ingot, by using the processing fluid. Here, the machining fluid is supplied to the workpiece and brought into contact with the workpiece. The machining fluid lubricates the area between the workpiece and the wire saw or other machining tool. The machining fluid is also used to remove chips, prevent rust on the workpiece, and cool the tool and the workpiece. Specific examples of the processing of brittle materials using the processing liquid include cutting, grinding, punching, polishing, drawing, drawing, and rolling. Of these, cutting and grinding are preferred, and cutting is more preferred. Examples of brittle materials to be processed include the materials mentioned above. As described above, the working fluid is preferably used for cutting a silicon ingot.

[0057] More specifically, in both wire saw processing methods, the free abrasive method and the fixed abrasive method, a multi-wire saw device is used to cut out a plurality of silicon wafers from the silicon ingot at once. In the multi-wire saw device, a wire is wound around each groove on two or more guide rollers on which a plurality of grooves are carved at regular intervals, and each wire is held parallel with a certain tension. During cutting, each guide roller is rotated, and the wire is run in one or both directions while the processing fluid discharged from a nozzle or the like is attached to the wire, and the silicon ingot is pressed against the wire to which the processing fluid is attached to cut it. In addition, processing may be performed while the processing fluid is applied to the workpiece itself, such as a silicon ingot, as necessary. The machining fluid used in machining is stored in a tank or the like, and is transported from there to the machining chamber nozzle via piping or the like. The machining fluid used during cutting is collected in a used machining fluid receiving tank or the like located at the bottom of the cutting device. In some cases, the machining fluid is circulated within the device and reused.

[0058] The machining fluid according to one embodiment of the present invention has an excellent balance of lubrication, defoaming and cleanliness properties, and can contribute to high machining precision and productivity (improved yield). Therefore, the machining fluid of one embodiment of the present invention is more preferably used as a machining fluid for use in a processing method for such brittle materials, and among these, it is even more preferably used as a machining fluid for use in a processing method for cutting silicon wafers from a silicon ingot using a fixed abrasive wire, and even more preferably used in a processing method for cutting silicon wafers from a silicon ingot using a multi-wire device with a fixed abrasive wire saw. The machining liquid according to one embodiment of the present invention also exhibits the above-mentioned excellent effects when a wire (preferably a fixed abrasive wire) having a thinner wire diameter (element wire) is used to cut silicon wafers from a silicon ingot, and is therefore even more suitably used in a machining method for cutting silicon wafers for solar cells from a silicon ingot.

[0059] Here, the strand diameter of the wire used for processing the brittle material can be appropriately selected depending on the application, but is, for example, preferably 55 μm or less, more preferably 54 μm or less, even more preferably 53 μm or less, and is preferably 30 μm or more, more preferably 35 μm or more, even more preferably 38 μm or more.

[0060] [Processing equipment] The brittle material processing apparatus according to one embodiment of the present invention is a processing apparatus that uses the processing fluid according to one embodiment of the present invention, and is preferably a multi-wire cutting processing apparatus, more preferably a multi-wire cutting processing apparatus equipped with a fixed abrasive wire saw, and even more preferably a multi-wire cutting processing apparatus equipped with a fixed abrasive wire saw for cutting silicon ingots.

[0061] [Composition for processing fluid] Furthermore, the processing fluid according to one embodiment of the present invention may be obtained, for example, by diluting a concentrated solution obtained by reducing the amount of water in the processing fluid and concentrating the processing fluid by 20 to 2,000 times, or a composition having the same composition as the concentrated solution, with water. That is, when carrying out the above-mentioned processing, a concentrated solution of the processing fluid or a composition for the processing fluid having the same composition as the concentrated solution (hereinafter also simply referred to as a "composition for processing fluid") can be diluted with water by 20 to 2,000 times and used as the processing fluid. For example, the working fluid can be made into a working fluid composition and used in an embodiment suitable for storage, transportation, and the like. Here, in this specification, the "composition for machining fluid" is not limited to a concentrated composition obtained by reducing the amount of water from a machining fluid, as described above, but also includes a composition prepared on the premise that it will be diluted with water to become a machining fluid. Note that the composition prepared on the premise that it will be diluted with water to become a machining fluid also includes a composition that is not simply diluted with water to become the machining fluid, but is used by adding some components to the composition later and adjusting the amounts so that each component falls within the ranges described above for the machining fluid before the above-mentioned processing is performed.

[0062] As an embodiment of the composition for machining fluid, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Ingredient (D): Water A composition for a machining fluid comprising: The content of component (A) is 0.200% by mass or more based on the total amount (100% by mass) of the composition for machining fluid; The content of component (B) is 0.100 mass% or more and 92.000 mass% or less based on the total amount of the composition for machining fluid (100 mass%), and The working fluid composition may have a content of component (C) of 0.120% by mass or more based on 100% by mass of the total amount of the working fluid composition.

[0063] The working fluid composition may further contain other components in addition to the above-mentioned components (A) to (D) as long as the object of the present invention is not impaired. In addition, in the working fluid composition, component (A), component (B), component (C) and component (D), as well as other components that may be added optionally, are the same as those described above in the working fluid section, and preferred embodiments thereof are also the same, so detailed description thereof will be omitted. In addition, there are no particular limitations on the suitable content ranges of component (A), component (B), component (C) and component (D) as well as other components in the working fluid composition. However, when the working fluid composition is used after diluting 20 to 2,000 times with water, it is preferable that each of the components is contained so as to satisfy the suitable content ranges of each of the components described above in the working fluid section.

[0064] For example, the working fluid composition according to one embodiment of the present invention may be any of the following embodiments. [2-1] Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Ingredient (D): Water A composition for a machining fluid comprising: The content of component (A) is 0.200% by mass or more based on the total amount (100% by mass) of the composition for machining fluid; The content of component (B) is 0.100 mass% or more and 92.000 mass% or less based on the total amount of the composition for machining fluid (100 mass%), and The content of component (C) is 0.120% by mass or more based on the total amount (100% by mass) of the composition for processing fluid; Composition for processing fluid. [2-2] The content of component (A) is preferably 1.000 mass% or more, more preferably 2.500 mass% or more, even more preferably 5.000 mass% or more, and is preferably 91.780 mass% or less, more preferably 90.900 mass% or less, even more preferably 89.250 mass% or less, and still more preferably 86.500 mass% or less, based on 100 mass% of the total amount of the working fluid composition. [2-3] The working fluid composition according to the above item [2-1] or [2-2], wherein the content of component (B) is, based on 100 mass% of the total amount of the working fluid composition, preferably 0.500 mass% or more, more preferably 1.250 mass% or more, even more preferably 2.500 mass% or more, and preferably 91.680 mass% or less, more preferably 90.400 mass% or less, even more preferably 88.000 mass% or less, and still more preferably 84.000 mass% or less. [2-4] The working fluid composition according to any one of the above [2-1] to [2-3], wherein the content of component (C) is, based on 100 mass% of the total amount of the working fluid composition, preferably 0.600 mass% or more, more preferably 1.500 mass% or more, even more preferably 3.000 mass% or more, and is preferably 91.700 mass% or less, more preferably 90.500 mass% or less, even more preferably 88.250 mass% or less, and still more preferably 84.500 mass% or less. [2-5] The composition for working fluid according to any one of the above [2-1] to [2-4], wherein component (A) is a compound having a cloud point of 20°C or more and 50°C or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and propylene oxide, and having no acetylene group. [2-6] The composition for working fluid according to any one of the above [2-1] to [2-5], wherein component (B) is a compound having a cloud point of more than 50°C and not more than 80°C in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and propylene oxide, and having no acetylene group. [2-7] The working fluid composition according to any one of the above items [2-1] to [2-6], wherein the ratio of the content of the component (A) to the content of the component (B) [(A) / (B)], in terms of mass ratio, is preferably 1.00 or more, more preferably 1.50 or more, even more preferably 2.00 or more, and is preferably 20.00 or less, more preferably 15.00 or less, even more preferably 10.00 or less. [2-8] The composition for working fluid according to any one of the above items [2-1] to [2-7], wherein the ratio of the total content of the components (A) and (B) to the content of the component (C) [(A)+(B) / (C)], in terms of mass ratio, is preferably 1.00 or more, more preferably 1.20 or more, even more preferably 1.30 or more, and is preferably 20.00 or less, more preferably 15.00 or less, even more preferably 12.00 or less. [2-9] The working fluid composition according to any one of the above [2-1] to [2-8], wherein the content of component (D) is, based on 100 mass% of the total amount of the working fluid composition, preferably 8,000 mass% or more, more preferably 9,000 mass% or more, more preferably 10,000 mass% or more, even more preferably 12,000 mass% or more, and is preferably 99.580 mass% or less, more preferably 97.900 mass% or less, even more preferably 94.750 mass% or less, and still more preferably 89.500 mass% or less. [2-10] When the working fluid composition further contains other components, the total content of the other components in the working fluid composition is, based on 100 mass% of the total amount of the working fluid composition, preferably 0.002 mass% or more, more preferably 0.004 mass% or more, even more preferably 0.006 mass% or more, still more preferably 0.008 mass% or more, and is preferably 40.000 mass% or less, more preferably 35.000 mass% or less, even more preferably 30.000 mass% or less, still more preferably 27.000 mass% or less, and still more preferably 25.000 mass% or less. The working fluid composition according to any one of the above [2-1] to [2-9].

[0065] [2-11] When the working fluid composition further contains a pH adjuster as another component, the total content of the pH adjuster in the working fluid composition is, based on the total amount of the working fluid composition (100 mass%), preferably 0.002 mass% or more, more preferably 0.003 mass% or more, even more preferably 0.004 mass% or more, and is preferably 20.000 mass% or less, more preferably 10.000 mass% or less, even more preferably 2.000 mass% or less, and still more preferably 1.600 mass% or less. The working fluid composition according to any one of the above [2-1] to [2-10]. [2-12] The working fluid composition according to any one of the above [2-1] to [2-11], wherein the total content of the components (A), (B), (C) and (D) in the working fluid composition is, based on 100 mass% of the total amount of the working fluid composition, preferably 60.000 mass% or more, more preferably 65.000 mass% or more, even more preferably 70.000 mass% or more, still more preferably 73.000 mass% or more, still more preferably 75.000 mass% or more, and preferably 100.000 mass% or less, more preferably 99.998 mass% or less, even more preferably 99.996 mass% or less, still more preferably 99.994 mass% or less, and still more preferably 99.992 mass% or less. [2-13] The composition for working fluid according to any one of the above [2-1] to [2-12], having a pH of preferably 3.0 or more, more preferably 4.0 or more, even more preferably 5.0 or more, and preferably 9.0 or less, more preferably 8.5 or less, even more preferably 8.0 or less. [2-14] The composition for machining fluid according to any one of the above [2-1] to [2-13], which is used when machining a workpiece made of a brittle material using a wire. [2-15] The composition for machining fluid according to the above [2-14], wherein the wire is a fixed abrasive wire. [2-16] The composition for a working fluid according to the above [2-14] or [2-15], wherein the brittle material is crystalline silicon, sapphire, silicon carbide, gallium nitride, neodymium magnet, quartz crystal, or glass.

[0066] [Method of manufacturing the composition for machining fluid] The working fluid composition can be produced, for example, by the following production method. That is, the method for producing a composition for a working fluid according to any one of the above items [2-1] to [2-16] includes the steps of: at least, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Ingredient (D): Water A method for producing a composition for a machining fluid, comprising: The content of component (A) is 0.200% by mass or more based on the total amount (100% by mass) of the composition for machining fluid; The content of component (B) is 0.100 mass% or more and 92.000 mass% or less based on the total amount of the composition for machining fluid (100 mass%), and The content of component (C) is 0.120% by mass or more based on 100% by mass of the total amount of the composition for machining fluid; The present invention relates to a method for producing a working fluid composition, and

[0067] The order in which components (A) to (D) are mixed is not particularly limited. For example, components (A), (B) and (C) may be mixed sequentially or simultaneously with water, which is component (D). Alternatively, components (A), (B) and (C) may be mixed in advance, and the mixture may be mixed with water, which is component (D). In the production method, components (A) to (D) are blended, and other components may be blended as necessary. In this case, the order of blending the components, the blending method, etc. are not particularly limited. In addition, component (A), component (B), component (C), component (D) and other components are the same as those described above in the section on working fluids, and the preferred embodiments are also the same, so detailed descriptions thereof will be omitted. In addition, the preferred amounts of component (A), component (B), component (C), component (D) and other components and the preferred ratios of the amounts of each component are the same as the respective contents and the respective content ratios in the working fluid composition described above in the sections [2-1] to [2-16], so detailed descriptions thereof will be omitted.

[0068] [Method of using the machining fluid composition] As described above, the working fluid composition can be used mainly for preparing the working fluid by diluting it with water. That is, a method for using the composition for machining fluid according to one embodiment of the present invention includes, for example, diluting the composition for machining fluid with water, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Ingredient (D): Water A machining fluid comprising: The content of component (A) is 0.010% by mass or more based on 100% by mass of the total amount of the processing fluid, The content of component (B) is 0.005% by mass or more and 0.090% by mass or less based on 100% by mass of the total amount of the processing fluid, and The content of component (C) is 0.006% by mass or more based on 100% by mass of the total amount of the processing fluid, The processing liquid is prepared so as to obtain The working fluid of the present invention can be used in the applications of the working fluid and the method of processing brittle materials described above in the working fluid section.

[0069] Therefore, the working fluid composition according to the embodiments described in [2-1] to [2-16] above can be further diluted with water and, if necessary, the contents of components (A) to (C) can be adjusted to use it as a working fluid according to one embodiment of the present invention. An example of the working fluid is the working fluid according to the embodiments described in the above [1] to

[12] , which is obtained by diluting the working fluid composition according to the embodiments described in the above [2-1] to [2-16] with water and adjusting the contents of the components (A) to (C) as necessary. The dilution ratio when the working fluid composition is diluted with water, which is component (D), is not particularly limited as long as the working fluid can be prepared, but is preferably 20 times or more, more preferably 100 times or more, even more preferably 250 times or more, still more preferably 500 times or more, and is preferably 2,000 times or less, more preferably 1,800 times or less, even more preferably 1,500 times or less, and still more preferably 1,000 times or less, calculated based on the total amount (mass) of the working fluid composition.

[0070] On the other hand, as described above, for example, the working fluid composition according to the embodiment described in [2-1] to [2-16] may itself be obtained as a concentrated liquid obtained by reducing the amount of water, which is component (D) in the working fluid according to one embodiment of the present invention. One embodiment of the working fluid composition may be, for example, the working fluid composition according to the embodiment described in [2-1] to [2-16], which is obtained by concentrating the working fluid according to the embodiment described in [1] to

[12] by 20 to 2,000 times by reducing the amount of component (D) by distillation or the like. The concentration ratio when the processing fluid is concentrated by reducing the amount of water, which is component (D), is not particularly limited, but is preferably 20 times or more, more preferably 100 times or more, even more preferably 250 times or more, still more preferably 500 times or more, and is preferably 2,000 times or less, more preferably 1,800 times or less, even more preferably 1,500 times or less, and still more preferably 1,000 times or less, calculated based on the total amount (mass) of the processing fluid.

[0071] In addition, the uses of the machining fluid obtained by using the machining fluid composition described in [2-1] to [2-16], the processing method for brittle materials using the machining fluid obtained by using the machining fluid composition, and the processing equipment are the same as those described in the corresponding items in the column for the machining fluid, which is one embodiment of the present invention, and therefore detailed description thereof will be omitted.

[0072] [Brittle material processing fluid composition] Further, as a brittle material processing fluid composition related to one embodiment of the present invention, the following brittle material processing fluid composition can be mentioned. A brittle material processing fluid composition comprising an additive mixture containing the following components (A) to (C), and component (D): water, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): one or more selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less; In the additive mixture, The content of component (A) is 20.00% by mass or more based on the total amount of the additive mixture (100% by mass), The content of component (B) is 5.00% by mass or more and 53.50% by mass or less based on the total amount of the additive mixture (100% by mass), and The content of component (C) is 5.00% by mass or more based on the total amount of the additive mixture (100% by mass). Brittle material processing fluid composition.

[0073] The brittle material processing fluid composition may further contain other components in addition to the above-mentioned components (A) to (D) within the scope of the invention. In addition, in the brittle material processing fluid composition, component (A), component (B), component (C) and component (D), as well as other components that may be added optionally, are the same as those described above in the section on the processing fluid, and their preferred embodiments are also the same, so detailed explanations thereof will be omitted.

[0074] More specifically, the following embodiments can be mentioned as examples of the brittle material processing fluid composition related to one embodiment of the present invention. [3-1] A brittle material processing fluid composition comprising an additive mixture containing the following components (A) to (C), and component (D): water, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): one or more selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less; In the additive mixture, The content of component (A) is 20.00% by mass or more based on the total amount of the additive mixture (100% by mass), The content of component (B) is 5.00% by mass or more and 53.50% by mass or less based on the total amount of the additive mixture (100% by mass), and The content of component (C) is 5.00% by mass or more based on the total amount of the additive mixture (100% by mass). Brittle material processing fluid composition. [3-2] The content of component (A) is preferably 24.00 mass% or more, more preferably 27.00 mass% or more, even more preferably 30.00 mass% or more, still more preferably 40.00 mass% or more, and is preferably 80.50 mass% or less, more preferably 79.50 mass% or less, even more preferably 78.50 mass% or less, based on 100 mass% of the total amount of the additive mixture. [3-3] The content of component (B) is preferably 6.50 mass% or more, more preferably 8.00 mass% or more, even more preferably 10.00 mass% or more, and is preferably 50.00 mass% or less, more preferably 47.50 mass% or less, even more preferably 45.00 mass% or less, based on 100 mass% of the total amount of the additive mixture. [3-4] The content of component (C) is, based on 100 mass% of the total amount of the additive mixture, preferably 6.00 mass% or more, more preferably 6.50 mass% or more, even more preferably 7.00 mass% or more, and preferably 55.00 mass% or less, more preferably 50.00 mass% or less, even more preferably 47.00 mass% or less, and still more preferably 42.00 mass% or less. [3-5] The brittle material processing fluid composition according to any one of the above [3-1] to [3-4], wherein component (A) is a compound having a cloud point of 20°C or more and 50°C or less in a 1% by mass aqueous solution, containing a copolymerization portion of ethylene oxide and propylene oxide, and having no acetylene group. [3-6] The brittle material processing fluid composition according to any one of the above [3-1] to [3-5], wherein component (B) is a compound having a cloud point of more than 50°C and not more than 80°C in a 1% by mass aqueous solution, containing a copolymerization portion of ethylene oxide and propylene oxide, and having no acetylene group. [3-7] The brittle material processing fluid composition according to any one of the above [3-1] to [3-6], wherein the ratio of the content of the component (A) to the content of the component (B) [(A) / (B)], in terms of mass ratio, is preferably 1.00 or more, more preferably 1.50 or more, even more preferably 2.00 or more, and is preferably 20.00 or less, more preferably 15.00 or less, even more preferably 10.00 or less. [3-8] The brittle material processing fluid composition according to any one of the above [3-1] to [3-7], wherein the ratio of the total content of the components (A) and (B) to the content of the component (C) [(A)+(B) / (C)], in terms of mass ratio, is preferably 1.00 or more, more preferably 1.20 or more, even more preferably 1.30 or more, and is preferably 20.00 or less, more preferably 15.00 or less, even more preferably 12.00 or less. [3-9] The brittle material processing fluid composition according to any one of the above [3-1] to [3-8], wherein the total content of component (A), component (B) and component (C) in the additive mixture is, based on 100 mass% of the total amount of the additive mixture, preferably 80.00 mass% or more, more preferably 85.00 mass% or more, even more preferably 90.00 mass% or more, still more preferably 95.00 mass% or more, still more preferably 99.00 mass% or more, and is 100.00 mass% or less, preferably 99.90 mass% or less, more preferably 99.80 mass% or less, still more preferably 99.75 mass% or less, and still more preferably 99.70 mass% or less. [3-10] When the brittle material processing fluid composition further contains other components, the total content of the other components in the brittle material processing fluid composition is, based on 100 mass% of the total amount of the additive mixture, preferably 0.10 mass% or more, more preferably 0.20 mass% or more, even more preferably 0.25 mass% or more, still more preferably 0.30 mass% or more, and preferably 20.00 mass% or less, more preferably 15.00 mass% or less, even more preferably 10.00 mass% or less, still more preferably 5.00 mass% or less, and still more preferably 1.00 mass% or less. The brittle material processing fluid composition according to any one of the above [3-1] to [3-9].

[0075] [3-11] The brittle material processing fluid composition according to any one of the above [3-1] to [3-10], containing component (D) in an amount of preferably 8 parts by mass or more, more preferably 9 parts by mass or more, even more preferably 10 parts by mass or more, still more preferably 11 parts by mass or more, still more preferably 12 parts by mass or more, and preferably 1,000,000 parts by mass or less, more preferably 500,000 parts by mass or less, even more preferably 250,000 parts by mass or less, and still more preferably 200,000 parts by mass or less, per 100 parts by mass of the additive mixture. [3-12] The brittle material processing fluid composition according to any one of the above [3-1] to [3-11], containing component (D) in an amount of preferably 1,000 parts by mass or more, more preferably 2,000 parts by mass or more, even more preferably 5,000 parts by mass or more, still more preferably 10,000 parts by mass or more, still more preferably 20,000 parts by mass or more, still more preferably 25,000 parts by mass or more, and preferably 1,000,000 parts by mass or less, more preferably 500,000 parts by mass or less, still more preferably 250,000 parts by mass or less, and still more preferably 200,000 parts by mass or less, per 100 parts by mass of the additive mixture. [3-13] The brittle material processing fluid composition according to any one of the above [3-1] to [3-11], containing component (D) in an amount of preferably 8 parts by mass or more, more preferably 9 parts by mass or more, even more preferably 10 parts by mass or more, still more preferably 11 parts by mass or more, still more preferably 12 parts by mass or more, and preferably 100,000 parts by mass or less, more preferably 50,000 parts by mass or less, even more preferably 25,000 parts by mass or less, still more preferably 10,000 parts by mass or less, still more preferably 5,000 parts by mass or less, still more preferably 2,000 parts by mass or less, and still more preferably 1,000 parts by mass or less, per 100 parts by mass of the additive mixture. [3-14] The brittle material processing fluid composition according to any one of the above [3-1] to [3-13], having a pH of preferably 3.0 or more, more preferably 4.0 or more, even more preferably 5.0 or more, and preferably 9.0 or less, more preferably 8.0 or less, even more preferably 7.0 or less. [3-15] The fluid composition for working a brittle material according to any one of the above [3-1] to [3-14], which is used when working a workpiece made of a brittle material with a wire. [3-16] The brittle material processing fluid composition according to the above [3-15], wherein the wire is a fixed abrasive wire. [3-17] The brittle material processing fluid composition according to [3-15] or [3-16], wherein the brittle material is crystalline silicon, sapphire, silicon carbide, gallium nitride, neodymium magnet, quartz crystal, or glass.

[0076] [Method for producing brittle material processing fluid composition] The brittle material processing fluid composition can be produced, for example, by the following production method. That is, the method for producing a brittle material processing fluid composition according to any one of the above [3-1] to [3-17] is as follows: A method for producing a brittle material processing fluid composition, comprising blending an additive mixture containing at least the following components (A) to (C), and component (D): water, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): one or more selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less; In the additive mixture, The content of component (A) is 20.00% by mass or more based on the total amount of the additive mixture (100% by mass), The content of component (B) is 5.00% by mass or more and 53.50% by mass or less based on the total amount of the additive mixture (100% by mass), and The content of component (C) is 5.00% by mass or more based on 100% by mass of the total amount of the additive mixture; The method for producing a brittle material processing fluid composition includes blending the components so as to obtain a brittle material processing fluid composition.

[0077] The order in which components (A) to (D) are mixed is not particularly limited. For example, components (A), (B) and (C) may be mixed sequentially or simultaneously with water, which is component (D). Alternatively, components (A), (B) and (C) may be mixed in advance, and the mixture may be mixed with water, which is component (D). In the production method, components (A) to (D) are blended, and other components may be blended as necessary. In this case, the order of blending the components, the blending method, etc. are not particularly limited. In addition, component (A), component (B), component (C), component (D) and other components are the same as those described above in the section on processing fluids, and the preferred embodiments are also the same, so detailed descriptions thereof will be omitted. In addition, the preferred amounts of component (A), component (B), component (C), component (D) and other components and the preferred ratios of amounts of each component are the same as those described above in sections [3-1] to [3-17], so detailed descriptions thereof will be omitted.

[0078] In addition, the uses of the brittle material processing fluid composition described in [3-1] to [3-17], the brittle material processing method using the brittle material processing fluid composition, and the processing equipment are the same as those described in the corresponding items in the processing fluid column, which is one embodiment of the present invention, and therefore detailed explanations are omitted. EXAMPLES

[0079] Hereinafter, one embodiment of the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples in any way. The physical properties of each component and the processing fluid were evaluated according to the procedures described below.

[0080] [Cloud point of 1% by weight aqueous solution] The cloud points of 1% by mass aqueous solutions of components (A) and (B) were measured by introducing 100 mL of a 1% by mass aqueous solution of the components to be measured into a 200 mL beaker, stirring the aqueous solution at a rotation speed of 400 rpm using a magnetic stirrer (stirrer length: 30 mm), and heating the aqueous solution from 15°C to the cloud point at a temperature increase rate of 5°C / min, and measuring the liquid temperature at which the aqueous solution became cloudy in appearance. The "cloud point" of the compounds shown in Tables 1 and 2 below refers to the "cloud point of a 1% by mass aqueous solution" of the compound.

[0081] [HLB value] The HLB value of component (C) was calculated by the Griffin method.

[0082] [Mass average molecular weight] The mass average molecular weight (Mw) was measured by gel permeation chromatography (GPC). The GPC was performed using two columns of "TSKgel (registered trademark) SuperMultiporeHZ-M" manufactured by Tosoh Corporation, tetrahydrofuran as an eluent, and a refractive index detector as a detector, and the mass average molecular weight (Mw) was determined using polystyrene as a standard sample.

[0083] [surface tension] The surface tension of each of the machining fluids obtained in the examples and comparative examples was measured in accordance with the platinum plate method described in JIS K 2241:2017.

[0084] [pH value] The pH of each of the machining fluids obtained in the examples and comparative examples was evaluated using a glass electrode type hydrogen ion concentration indicator (model: HM-25R) manufactured by DKK-TOA Corporation.

[0085] [Silicon (Si) friction coefficient] Using each of the machining fluids obtained in the examples and comparative examples, a reciprocating friction test was carried out under the following test conditions to measure the friction coefficient. Reciprocating friction tester: "F-2100" manufactured by Orientec Co., Ltd. Bulb: 3 / 16 inch SUJ2 Test temperature: 50℃ Test plate: Polycrystalline silicon (surface polished to a mirror finish) Test plate temperature: 50℃ Sliding speed: 20mm / sec Sliding distance: 2cm Number of round trips: 50 Load: 200g

[0086] [Evaluation of antifoaming properties] The machining fluids obtained in the examples and comparative examples were evaluated according to the following procedures. 90 mL of the processing liquid was introduced into a 100 mL measuring cylinder, the measuring cylinder was covered, and the cylinder was vigorously shaken up and down 10 times. After leaving the cylinder to stand for 20 seconds, the liquid level was measured. The liquid level is measured in units of "mL" (in 0.5 mL increments) using the scale on the measuring cylinder. At this time, when foaming occurs, the liquid level becomes higher, i.e., the value in "mL" becomes larger, so the smaller the value (mL) of the liquid level becomes, the better the defoaming ability becomes. For example, when the liquid level becomes 93.5mL due to foaming, the increase of 3.5mL from the height of the measuring cylinder before shaking, 90.0mL, is regarded as the liquid level, and is shown in Tables 1 and 2 below.

[0087] [Cleaning evaluation] The machining fluids obtained in the examples and comparative examples were evaluated according to the following procedures. (Cylinder wall dirt evaluation) 90 mL of the processing liquid and 0.5 g of fine powder ("graphite powder", Fujifilm Wako Pure Chemical Industries, Ltd., special grade) were placed in a 100 mL measuring cylinder, the measuring cylinder was capped, and the cylinder was vigorously shaken up and down 10 times. The degree of dirt on the upper part of the inner wall of the measuring cylinder was evaluated according to the following criteria. A: The cylinder wall is slightly stained with fine powder, and the background near the liquid surface is visible. B: The cylinder wall is heavily soiled with fine powder, making it impossible to see the background near the liquid surface.

[0088] [Examples 1 to 8 and Comparative Examples 1 to 8] The components were mixed to obtain the compositions shown in Tables 1 and 2 below to prepare the machining fluids of Examples 1 to 8 and Comparative Examples 1 to 8. The machining fluids of the Examples and Comparative Examples were evaluated according to the evaluation methods described above. The results are shown in Tables 1 and 2 below.

[0089] The components shown in Tables 1 and 2 below respectively represent the following compounds. <Component (A)> Compound A1: Polyoxyalkylene alkyl ether in which the polyoxyalkylene portion is a random copolymer of ethylene oxide (EO) and propylene oxide (PO) (terminal methyl group (terminal alkyl group portion), mass average molecular weight (Mw) = 4,597, EO / PO ratio (molar ratio) = 42 / 58, cloud point of 1% by mass aqueous solution = 43°C) Compound A2: poly(propylene oxide)-poly(ethylene oxide)-poly(propylene oxide) type block copolymer (mass average molecular weight (Mw) = 4,261, EO / PO ratio (molar ratio) = 30 / 70, cloud point of 1% by weight aqueous solution = 38°C) Compound A3: Poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) type block copolymer (cloud point of 1% by weight aqueous solution = 23°C)

[0090] <Ingredient (B)> Compound B1: poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) type block copolymer (mass average molecular weight (Mw) = 5,654, EO / PO ratio (molar ratio) = 48 / 52, cloud point of 1% by weight aqueous solution = 63°C) Compound B2: poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) type block copolymer (mass average molecular weight (Mw) = 5,498, EO / PO ratio (molar ratio) = 52 / 48, cloud point of 1% by weight aqueous solution = 61°C)

[0091] <Component (C)> Compound C1: EO adduct of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol (EO adduct of acetylene glycol, HLB=8) <Ingredient (D)> Ion-exchanged water

[0092] <Other ingredients> Compound S1: EO adduct of 2,4,7,9-tetramethyl-5-decyne-4,7-diol (EO adduct of acetylene glycol, HLB=13) pH adjuster 1: Isononanoic acid pH adjuster 2: Triisopropanolamine

[0093] [Table 1]

[0094] [Table 2]

[0095] As shown in Table 1, the machining fluids of Examples 1 to 8 contain components (A) to (D) and each contains components (A) to (C) in a specified amount. Therefore, all of the machining fluids have excellent lubricity, antifoaming properties, and cleanliness, and it was confirmed that the machining fluids have an excellent balance of lubricity, antifoaming properties, and cleanliness. On the other hand, as shown in Table 2, the machining fluids of Comparative Examples 1 to 8 did not contain any of the components (A), (B) or (C) (Comparative Examples 1, 3, 6, and 7), or did not satisfy the requirement of containing the components (A) to (C) in the specified contents (Comparative Examples 2, 4, 5, and 8), and were therefore confirmed to be inferior in any of the properties of lubricity, defoaming property, or detergency. Using the machining fluid described in Example 1 and a fixed abrasive wire with a wire diameter of 52 μm, a silicon ingot was cut using a fixed abrasive multi-wire saw device. As a result, it was confirmed that the machining fluid had excellent defoaming and cleanliness during processing. It was also confirmed that the cutting accuracy of the silicon ingot was good and the wire breakage rate was less than 5%. The "cutting accuracy" was evaluated by measuring the TTV (Total Thickness Variation), which is the deviation in thickness of the cut silicon wafer. In Example 1, the average TTV value of the silicon wafer obtained by cutting one ingot was 15 μm or less, which was good. In contrast, in Comparative Example 1, the average TTV value of the silicon wafer obtained by cutting one ingot exceeded 15 μm. In addition, the "wire breakage rate (unit: %)" is a value calculated by "number of times wire breakage occurred / number of cut ingots x 100". For example, when 100 silicon ingots were cut and processed, if wire breakage occurred during processing of 5 of the silicon ingots, the wire breakage rate was evaluated as 5%. [Industrial Applicability]

[0096] The machining fluid according to one embodiment of the present invention has an excellent balance of lubricity, antifoaming properties, and cleanliness properties. Because of its excellent lubricity, it is expected to improve the processing efficiency when cutting workpieces made of brittle materials such as silicon ingots, suppress friction between the workpiece and the tool used to process it, reduce frictional heat generated during processing, and extend the life of the tool. Furthermore, it is possible to obtain excellent processing accuracy even when processing using thinner wires. Furthermore, for example, when cutting the above-mentioned workpiece, foaming of the processing fluid can be suppressed, thereby preventing problems such as the processing fluid overflowing from a tank receiving the processing fluid due to foaming (occurrence of an overflow), or adverse effects such as reduced processing accuracy due to foaming. In addition, because of its excellent cleanability, for example, when cutting the above-mentioned workpiece, contamination by fine powder such as cutting chips from a processing machine such as a cutting machine used in the processing or from a workpiece such as a cut material can be suppressed. As a result, the processing machine and the workpiece can be easily cleaned. As described above, the machining fluid of one embodiment of the present invention has an excellent balance of lubricity, defoaming properties, and cleanliness properties, and can contribute to improving the productivity of products obtained by cutting a workpiece made of a brittle material, such as a silicon ingot. As described above, the working fluid according to one embodiment of the present invention is preferably used as a working fluid for cutting brittle materials such as silicon ingots, etc. The working fluid according to one embodiment of the present invention has an excellent balance of lubricity, defoaming properties, and cleanliness, and can also suppress wire breakage, which contributes to high processing accuracy and productivity (improved yield), and is more preferably used as a coolant for cutting silicon wafers from silicon ingots using a fixed abrasive wire.

Claims

1. Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Component (D): water A machining fluid comprising: The content of component (A) is 0.010% by mass or more and 0.200% by mass or less based on 100% by mass of the total amount of the processing fluid, The content of component (B) is 0.005% by mass or more and 0.090% by mass or less based on the total amount of the processing fluid (100% by mass), and The content of component (C) is 0.006% by mass or more and 0.100% by mass or less based on 100% by mass of the total amount of the processing fluid, A processing fluid used when machining workpieces made of brittle materials using a wire.

2. 2. The processing fluid according to claim 1, wherein the component (A) is a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and propylene oxide, and having no acetylene group.

3. 3. The processing fluid according to claim 1 or 2, wherein the component (B) is a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and propylene oxide, and having no acetylene group.

4. The processing fluid according to any one of claims 1 to 3, wherein the ratio of the content of component (A) to the content of component (B) [(A) / (B)] is 1.00 or more in terms of mass ratio.

5. The processing fluid according to any one of claims 1 to 4, wherein a ratio of a total content of the components (A) and (B) to a content of the component (C) [(A) + (B) / (C)] is 1.00 or more in terms of mass ratio.

6. The working fluid according to any one of claims 1 to 5, wherein the content of component (D) is 95.000 mass% or more and 99.979 mass% or less, based on 100 mass% of the total amount of the working fluid.

7. The machining fluid according to any one of claims 1 to 6, having a pH of 3.0 or more and 9.0 or less.

8. The machining fluid according to any one of claims 1 to 7, wherein the wire is a fixed abrasive wire.

9. The working fluid according to any one of claims 1 to 8, wherein the brittle material is crystalline silicon, sapphire, silicon carbide, gallium nitride, neodymium magnet, quartz crystal, or glass.

10. at least, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Component (D): water A method for producing a processing fluid, comprising: The content of component (A) is 0.010% by mass or more and 0.200% by mass or less based on 100% by mass of the total amount of the processing fluid, The content of component (B) is 0.005% by mass or more and 0.090% by mass or less based on the total amount of the processing fluid (100% by mass), and The content of component (C) is 0.006% by mass or more and 0.100% by mass or less based on 100% by mass of the total amount of the processing fluid; The method for producing a working fluid according to any one of claims 1 to 9, wherein the working fluid is obtained by blending the components so as to satisfy the following formula:

11. Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Component (D): water A composition for a machining fluid comprising: The content of component (A) is 5.000 mass% or more and 86.500 mass% or less based on 100 mass% of the total amount of the working fluid composition, The content of component (B) is 2.500 mass% or more and 84.000 mass% or less based on the total amount of the working fluid composition (100 mass%), and The content of component (C) is 3.000 mass% or more and 84.500 mass% or less based on 100 mass% of the total amount of the working fluid composition, A composition for a machining fluid used when machining a workpiece made of a brittle material using a wire.

12. at least, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): at least one selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, and Component (D): water A method for producing a composition for a machining fluid, comprising: The content of component (A) is 5.000 mass% or more and 86.500 mass% or less based on 100 mass% of the total amount of the working fluid composition, The content of component (B) is 2.500 mass% or more and 84.000 mass% or less based on the total amount of the working fluid composition (100 mass%), and The content of component (C) is 3.000% by mass or more and 84.500% by mass or less based on 100% by mass of the total amount of the working fluid composition; The method for producing a working fluid composition according to claim 11, wherein the working fluid composition is obtained by blending the components so as to satisfy the following formula:

13. A brittle material processing fluid composition comprising an additive mixture containing the following components (A) to (C), and component (D): water, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): one or more selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, In the additive mixture, The content of component (A) is 20.00% by mass or more and 80.50% by mass or less based on 100% by mass of the total amount of the additive mixture, The content of component (B) is 5.00% by mass or more and 53.50% by mass or less based on the total amount of the additive mixture (100% by mass), and The content of component (C) is 5.00% by mass or more and 50.00% by mass or less based on 100% by mass of the total amount of the additive mixture, A brittle material processing fluid composition for use when processing a workpiece made of a brittle material using a wire.

14. A method for producing a brittle material processing fluid composition, comprising blending an additive mixture containing at least the following components (A) to (C), and component (D): water, Component (A): a compound having a cloud point of 20° C. or more and 50° C. or less in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (B): a compound having a cloud point of more than 50° C. and not more than 80° C. in a 1% by mass aqueous solution, containing a copolymerization site of ethylene oxide and an alkylene oxide other than ethylene oxide, and having no acetylene group; Component (C): one or more selected from the group consisting of acetylene glycol having an HLB value of 4 or more and 12 or less, and alkylene oxide adducts of acetylene glycol having an HLB value of 4 or more and 12 or less, In the additive mixture, The content of component (A) is 20.00% by mass or more and 80.50% by mass or less based on 100% by mass of the total amount of the additive mixture, The content of component (B) is 5.00% by mass or more and 53.50% by mass or less based on the total amount of the additive mixture (100% by mass), and The content of component (C) is 5.00% by mass or more and 50.00% by mass or less, based on 100% by mass of the total amount of the additive mixture; The method for producing a brittle material processing fluid composition according to claim 13, wherein the brittle material processing fluid composition is obtained by mixing the components so as to satisfy the following formula:

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