Water-soluble metal processing oil agent and coolant

Abstract

To provide a water-soluble metal processing oil agent composition that can suppress the overgrowth of slime-form mold in a coolant and can extend the coolant life even under conditions with many polyvalent metal ions, and a coolant using the same.SOLUTION: A water-soluble metal processing oil agent composition and a coolant comprise at least one oil-soluble amine selected from the group consisting of octyldiethanolamine, 3-amino-4-octanol, and dibenzylamine, at least one specific ether carboxylic acid, and a nonionic surfactant which is a polyoxyalkylene glycol block polymer and has a pluronic and / or reverse pluronic structure.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to water-soluble metalworking fluids and coolants used in machining various metal parts. [Background technology]

[0002] Water-soluble machining fluids used in metal machining come in various types, including solution, soluble, and emulsion. All of these contain ingredients such as water, alkaline substances (inorganic alkalis, organic alkaline compounds, etc.), mineral oil, grease, synthetic oil, organic acids, extreme-pressure additives, surfactants, antifoaming agents, metal corrosion inhibitors, preservatives, antifungal agents, and disinfectants. These additives are blended appropriately depending on the workpiece, processing conditions, and other factors. Water-soluble machining fluids are generally used as undiluted solutions, diluted with water to approximately 1-50% by weight. Hereinafter, this water-diluted liquid will be referred to as coolant.

[0003] In coolant, there is a problem in that bacteria and fungi use organic substances (including nitrogen compounds) contained in the oil components, as well as hydraulic oil and sliding surface lubricant oil that are mixed in from processing machinery, as a nutrient source, resulting in the generation of foul odors and a deterioration of the surrounding working environment. Furthermore, when mold grows in a slime-like form on the walls of coolant tanks or inside pipes, it can clog nozzles and filters, get tangled in cutting chips and cause machine and tank contamination, and if mold adheres to electrical systems it can cause short circuits. Such mold growth can cause machine malfunctions, requiring the removal of mold from tanks and pipes and repairs to electrical systems, which can necessitate work interruptions and reduce productivity. Furthermore, because coolant is normally recycled, the emulsifying power of the coolant can decrease due to the accumulation of polyvalent metal ions in the dilution water, the accumulation of polyvalent metal ions eluted from the workpiece and its chips, and the influence of contamination from hydraulic oil, sliding surface lubricant, etc., which can result in poor emulsification or oil separation. Depending on the degree of poor emulsification, oil separation, and the adverse effects of mold, it may become necessary to replace the entire amount of coolant. This is undesirable from the perspective of resource and energy conservation, so there is a need to develop an oil agent that can be used stably for a long period of time.

[0004] To prevent the growth of slime-like mold in tanks, piping, etc., water-soluble metalworking fluids and coolants have been treated with antifungal agents by adding antifungal agents and amines or adjusting the amount of other ingredients. Fungi such as mold have been dealt with in particular by incorporating oil-soluble amines such as dicyclohexylamine or isothiazolinone antifungal agents. However, dicyclohexylamine is a highly toxic substance and requires strict handling controls, and isothiazolinone antifungal agents are very expensive. Patent Document 1 is a prior art document containing octyldiethanolamine, but it uses it in combination with dicyclohexylamine. Patent Document 2 describes a water-soluble metalworking oil containing an ether carboxylic acid, but does not describe its use in combination with octyldiethanolamine, 3-amino-4-octanol, or dibenzylamine, and describes foaming as a problem. Patent Document 3 also describes ether carboxylic acids, but similarly describes foaming as a problem. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5255835 [Patent Document 2] Patent Publication No. 2008-214510 [Patent Document 3] Patent No. 3917676 Summary of the Invention [Problem to be solved by the invention]

[0006] The object of the present invention is to solve the above problems by preventing a decrease in productivity due to the need to deal with machine malfunctions caused by slime-like mold, and by preventing the coolant from becoming unstable due to the effects of polyvalent metal elution from workpieces and their chips, the accumulation of polyvalent metals in dilution water, etc. The object of the present invention is to provide a water-soluble metalworking oil and coolant that can inhibit the growth of mold in the coolant and extend the life of the coolant. [Means for solving the problem]

[0007] Octyldiethanolamine, 3-amino-4-octanol, and dibenzylamine have excellent antifungal properties, but when blended with water-soluble metalworking fluids, the organic acids and their salts typically contained in water-soluble metalworking fluids are highly oil-soluble, so the micelles tend to break down in the coolant state, and the emulsion becomes unstable, particularly in situations where there are a lot of polyvalent metal ions. As a result of extensive research into achieving the above-mentioned object, the inventors have found that the above-mentioned amine compounds inhibit the growth of mold, and that the use of ether carboxylic acids in combination improves the emulsion stability of the coolant and extends the coolant's lifespan. Furthermore, they have found that the above-mentioned object can be achieved by adding a specific nonionic surfactant, which suppresses foaming, a drawback of ether carboxylic acids, and improves the stability of the coolant. Based on this, they have conducted further studies and have completed the present invention.

[0008] The present invention provides the following water-soluble metalworking oil and coolant.

[0009] 1. A water-soluble metalworking oil composition comprising the following components (A), (B), and (C): (A) at least one oil-soluble amine selected from the group consisting of octyldiethanolamine, 3-amino-4-octanol, and dibenzylamine (B) at least one ether carboxylic acid represented by general formula 1 (C) A polyoxyalkylene glycol block polymer, a nonionic surfactant having a Pluronic or / and reverse Pluronic structure General formula 1 RO(CH2CH2O)nCH2COOH (In General Formula 1, R represents a saturated or unsaturated hydrocarbon group having 6 to 18 carbon atoms, and n represents an integer of 2 to 11.)

[0010] 2. The water-soluble metalworking oil composition according to Item 1, wherein, when the total amount of the water-soluble metalworking oil composition is taken as 100% by weight, the content of component (A) is 0.3 to 10.0% by weight, the content of component (B) is 0.3 to 10.0% by weight, and the content of component (C) is 0.5 to 50.0% by weight, and the content ratio of ethylene oxide (EO) to propylene oxide (PO) in component (C) is EO:PO=10:90 to 30:70.

[0011] 3. A coolant obtained by diluting the water-soluble metalworking oil composition according to item 1 or 2 with water. [Effects of the Invention]

[0012] According to the present invention, the following remarkable effects can be obtained.

[0013] When a coolant obtained by diluting the water-soluble metalworking oil of the present invention with water is used in metalworking, the growth of slime-like mold can be significantly suppressed, and the micelles are not easily broken down, so the coolant can be used stably for a long period of time. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is an explanatory diagram of the anti-foaming test. DETAILED DESCRIPTION OF THE INVENTION

[0015] The water-soluble metalworking oil and coolant of the present invention are characterized by containing (A) at least one oil-soluble amine selected from the group consisting of octyldiethanolamine, 3-amino-4-octanol, and dibenzylamine, (B) an ether carboxylic acid, and (C) a polyoxyalkylene glycol block polymer, in combination with a nonionic surfactant having a Pluronic or / and reverse Pluronic structure.

[0016] The content of (A) at least one selected from the group consisting of octyldiethanolamine, 3-amino-4-octanol, and dibenzylamine added to the water-soluble metalworking oil is preferably about 0.3 to 10.0% by weight, more preferably about 0.5 to 8.0% by weight, and even more preferably about 1.0 to 5.0% by weight, based on 100% by weight of the entire water-soluble metalworking oil composition of the present invention. If the content of any of octyldiethanolamine, 3-amino-4-octanol, and dibenzylamine is less than 0.3% by weight, the antifungal effect will be insufficient, while if it exceeds 10.0% by weight, it may have an adverse effect on emulsifiability, so neither is preferred.

[0017] The content of the ethercarboxylic acid (B) represented by general formula 1 added to the water-soluble metalworking oil is preferably about 0.3 to 10.0% by weight, more preferably about 0.5 to 8.0% by weight, and even more preferably about 1.0 to 5.0% by weight, when the entire water-soluble metalworking oil composition of the present invention is taken as 100% by weight. If the content of the ethercarboxylic acid is less than 0.3% by weight, the stability of the water-soluble metalworking oil and coolant will be insufficient, while if it exceeds 10.0% by weight, there is a risk of adversely affecting the foam-suppressing property, so neither is preferred. Furthermore, one or more types of ether carboxylic acids represented by general formula 1 are added. General formula 1 RO(CH2CH2O)nCH2COOH (In General Formula 1, R represents a saturated or unsaturated hydrocarbon group having 6 to 18 carbon atoms, and n represents an integer of 2 to 11.)

[0018] The polyoxyalkylene glycol block polymer (C) added to the water-soluble metalworking fluid is represented by the following formula: HO-(EO) m (PO) n (EO) m -H (Pluronic), HO-(PO) m (EO) n (PO) m -H (reverse Pluronic). The amount of the nonionic surfactant having a Pluronic or reverse Pluronic structure to be added is preferably about 0.5 to 50% by weight, when the total amount of the water-soluble metalworking oil composition of the present invention is taken as 100% by weight. The ethylene oxide (EO) to propylene oxide (PO) content ratio of the nonionic surfactants with Pluronic and reverse Pluronic structures is preferably EO:PO=10:90 to 30:70, and an EO content ratio of 40 or more is undesirable as it may affect the foam suppressing properties.

[0019] Ingredients other than the above oil-soluble amines, ether carboxylic acids, and nonionic surfactants The water-soluble metalworking fluid of the present invention may contain conventional additives, such as organic acids, amines, and surfactants other than those mentioned above, depending on the type of metalworking fluid. Furthermore, if necessary, additives such as inorganic alkaline substances, mineral oils, synthetic oils, oils and fats, ester compounds, extreme pressure additives, metal corrosion inhibitors, preservatives, and chelating agents (sequestering agents) may also be added. The amounts of these additives added are determined appropriately depending on the type of metalworking fluid. Examples of organic acids include C8 to C 36 Organic acids form organic acid amine salts with amines, which act as anionic surfactants to enhance emulsion stability, as well as to enhance rust prevention and lubricity, improving the primary and secondary performance of water-soluble metalworking fluids.

[0020] C8~C 36Examples of organic acids include monocarboxylic acids and dicarboxylic acids. Examples of monocarboxylic acids include octylic acid, 2-ethylhexanoic acid, pelargonic acid, isononanoic acid, isodecanoic acid, undecanoic acid, oleic acid, isostearic acid, ricinoleic acid condensates, etc.; examples of natural products include coconut oil fatty acid, tall oil fatty acid, and castor oil fatty acid. Examples of dicarboxylic acids include adipic acid, sebacic acid, dodecanedioic acid, C 21 C 36 and dicarboxylic acids thereof.

[0021] Organic acids with a carbon number of 7 or less may corrode metals, while those with a carbon number of more than 36 have the problem of being prone to foaming, and neither is preferred.

[0022] The amount of organic acids blended is preferably about 1.0 to 30% by weight, when the total amount of the water-soluble metalworking oil composition of the present invention is taken as 100% by weight.

[0023] Amines are added to increase the pH of the composition, thereby providing alkaline rust prevention and corrosion resistance, and because organic acid amine salts function as anionic surfactants. Primary amines, secondary amines, tertiary amines, etc. can be used singly or in combination of two or more.

[0024] Examples of primary amines include diglycolamine, monoisopropanolamine, 2-amino-2-methylpropanol, etc. Examples of secondary amines include diethanolamine, diisopropanolamine, N-methylethanolamine, N-ethylethanolamine, 2-(butylamino)ethanol, 2-((1-methylpropyl)amino)ethanol, etc. Examples of tertiary amines include triethanolamine, triisopropanolamine, N-methyldiethanolamine, cyclohexylamine EO 2 mole adduct, diethanol monoisopropanolamine, etc.

[0025] The amount of amine to be added is determined taking into consideration the concentration of the diluted solution when the resulting water-soluble metalworking oil composition is diluted with water and used as a coolant, the intended use, rust prevention, and corrosion resistance. Generally, the amount of amine added is preferably about 1.0 to 50% by weight, assuming the total amount of the water-soluble metalworking oil composition of the present invention to be 100% by weight. A total amount of amine exceeding 50% by weight is undesirable in terms of rough skin and cost, while a total amount of amine less than 1% by weight is undesirable because rust prevention and corrosion resistance are not observed.

[0026] As the surfactant, a nonionic surfactant, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, or the like can be used.

[0027] Common examples of nonionic surfactants include: RO(EO) n -H, R-(AO) n Examples of such alkylene compounds include -H and glycerin AO adducts. In each of these formulas, R represents an alkyl group (which may be linear or branched, and may have a cyclic structure, a double bond, a triple bond, etc.), and AO (alkylene oxide) represents a mixture of one or two of EO (ethylene oxide) and PO (propylene oxide), and the arrangement in the case of a mixture may be random or block. In addition, in each formula, n represents an integer of about 1 to 50. Anionic surfactants other than organic acid amine salts include petroleum-based sodium sulfonates.

[0028] The amount of the nonionic surfactant to be added is preferably about 0.5 to 10.0% by weight, when the total amount of the water-soluble metalworking oil composition of the present invention is taken as 100% by weight. The amount of petroleum-based sodium sulfonate blended is preferably about 0.5 to 10.0% by weight, when the total amount of the water-soluble metalworking oil composition of the present invention is taken as 100% by weight.

[0029] The water-soluble metalworking oil composition of the present invention contains water. The amount of water is usually preferably about 1 to 70% by weight, assuming the total amount of the water-soluble metalworking oil composition to be 100% by weight. The water used may be tap water, industrial water, ion-exchanged water, distilled water, or the like, and the water may be hard water or soft water.

[0030] Examples of metal corrosion inhibitors include imidazoline, benzotriazole, and polymer acid derivatives.

[0031] Examples of preservatives include triazine compounds, isothiazolinone compounds, pyridine compounds, iodine compounds, phenol compounds (such as phenoxyethanol), morpholine compounds, and ethylenedioxydimethanol.

[0032] coolant The coolant of the present invention is prepared by diluting the water-soluble metalworking oil composition of the present invention as a stock solution with water and using it as a coolant in metalworking. When the water-soluble metalworking oil composition is diluted with water for practical use, it is preferable to dilute the stock solution with water to a concentration of about 1.0 to 10.0% by weight and use it as a coolant. [Example]

[0033] The present invention will be described in more detail below based on examples and comparative examples, but the present invention is not limited to these examples in any way.

[0034] As examples and comparative examples, the components shown in Tables 1 to 4 were blended so that the total water-soluble metalworking oil composition was 100% by weight, and various tests were carried out. *1···HO-(EO) m (PO) n (EO) m -H EO:PO=10:90 MW:2220 *2···HO-(EO) m (PO) n (EO) m-H EO:PO=30:70 MW:2500 *3···HO-(PO) m (EO) n (PO) m -H EO:PO=10:90 MW:2700 *4···HO-(PO) m (EO) n (PO) m -H EO:PO=30:70 MW:2000 *5: Commercially available benzisothiazoline (BIT) preparations *6 Commercially available butyl benzisothiazoline (B-BIT) formulation *7: Commercially available sodium omadine preparation *8... EOPO adduct of alcohol *9 Mineral oil, naphthenic, kinematic viscosity 10 (mm 2 / s, 40℃)

[0035] [Table 1]

[0036] [Table 2]

[0037] [Table 3]

[0038] [Table 4]

[0039] Antiseptic efficacy test for water-soluble processing oils In a shouldered flask, 150 mL of a solution of water-soluble metalworking fluid diluted to 5% with water, 15 g of casting chips, and 10 mL of Vactra No. 2, a sliding surface lubricant, are placed. 7 10mL of decayed liquid, yeast count >10 6Add 10 mL of mold (+) putrefactive liquid to the flask every week for a total of 20 mL, and place in a constant temperature bath at 30°C. Check for the occurrence of slime-like mold and the number of live bacteria in the flask. Evaluation: Slime-like mold in the shoulder flask after 10 weeks (-): No occurrence (+): Occurrence Viable bacteria count ○:≦10 4 ×:>10 4

[0040] Hard water stability test for water-soluble machining oils Put 19 mL of hard water containing 500 ppm of magnesium hardness into a test tube, add 1 mL of water-soluble metalworking oil to it to make a 5% diluted solution, and check the emulsification state after one week. Evaluation: ○: Good emulsification △: Cream layer present, cloudy ×: Oil separation

[0041] Anti-foam test for water-soluble machining oils 16 L of a solution of water-soluble metalworking oil diluted to 5% with water is poured into the testing machine shown in Figure 1, and the foam height is checked after 7 hours. Evaluation: ○:<10cm ×:≧10cm

[0042] It is clear from Tables 1 to 4 that the coolant obtained by diluting the water-soluble metalworking oil composition of the present invention with water is significantly superior in antifungal effect and emulsion stability to the coolant obtained by diluting the comparative composition with water. [Industrial Applicability]

[0043] The water-soluble metalworking oil composition of the present invention can significantly inhibit the growth of slime-like mold when diluted with water to form a coolant for metalworking, can effectively prevent a decrease in productivity due to nozzle clogging, and maintains stable emulsifiability for a long period of time, making it extremely useful in the metalworking industry and related industries.

Claims

1. (A) At least one oil-soluble amine selected from the group consisting of octyldiethanolamine, 3-amino-4-octanol, and dibenzylamine (B) at least one ether carboxylic acid represented by general formula 1 (C) A water-soluble metalworking oil composition, characterized by containing a polyoxyalkylene glycol block polymer and a nonionic surfactant having a Pluronic or / and reverse Pluronic structure. General formula 1 RO (CH ２ CH ２ O)nCH ２ COOH (In General Formula 1, R represents a saturated or unsaturated hydrocarbon group having 6 to 18 carbon atoms, and n represents an integer of 2 to 11.)

2. 2. The water-soluble metalworking oil composition according to claim 1, wherein, when the total amount of the water-soluble metalworking oil composition is taken as 100% by weight, the content of component (A) is 0.3 to 10.0% by weight, the content of component (B) is 0.3 to 10.0% by weight, and the content of component (C) is 0.5 to 50.0% by weight, and the ratio of ethylene oxide (EO) to propylene oxide (PO) in component (C) is EO:PO=10:90 to 30:

70.

3. A coolant obtained by diluting the water-soluble metalworking oil composition according to claim 1 or 2 with water.

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