JP2017177082A - Cleaning method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning method which can clean a wide range of dirt from organic to inorganic one, can suppress occurrence of water stain after cleaning, and enables repeated use of a cleaning agent composition.SOLUTION: There is provided a cleaning method which includes: a cleaning step of applying a physical force to a cleaning agent composition made from two phases of an organic solvent (A) phase and a water (B) phase to form W/O macro emulsion, immersing a substance to be cleaned into the formed W/O emulsion, and cleaning the substance to be cleaned; a draining step of immersing the substance to be cleaned into a draining tank made from the organic solvent (A) phase, and draining the substance to be cleaned, after the cleaning step; and a rinsing step of immersing the substance to be cleaned into a rinsing tank made from the organic solvent (A), and rinsing the substance to be cleaned, after the draining step, where the organic solvent (A) phase is excellent in draining property.SELECTED DRAWING: None

Description

  The present invention relates to a cleaning method, in particular, parts handled in various industrial fields such as automobiles, machines, precision equipment, electricity, electronics, optics, pipes and devices of various factories such as oil refineries and chemical plants, automobiles and industrial machines. The present invention relates to a cleaning method used for cleaning various parts such as metal parts, resin products and textiles used in daily life.

  Conventionally, when processing parts handled in various industrial fields such as automobiles, machinery, precision equipment, electricity, electronics, optics, etc., (i) oil-based processing oil mainly composed of mineral oil, (ii) interface with mineral oil, etc. A water-soluble processing oil emulsified in water by adding an activator, and (iii) fine particles such as an abrasive are used. Many water-soluble processing oils are used mainly for cutting and grinding, but parts manufactured through a plurality of processing steps may use different processing oils for each step. In many cases, oil-based processing oil, water-soluble processing oil, fine particles and various kinds of dirt such as processing waste are mixed and mixed on the surface of the processed part. It is also used for various items such as pipes and equipment of various factories such as oil refining plants and chemical plants, parts dismantled from automobiles and industrial machinery, metal products used in daily life, resin products, and textiles. Various kinds of dirt such as grease, plastic, machine oil, coal tar, clay, sand, and fat are mixed and adhered.

  When cleaning an article with a mixture of various organic and inorganic soils, it is necessary to mix a chlorine-based solvent such as trichlorethylene and methylene chloride, an aqueous cleaner, and an aqueous cleaner with a water-soluble solvent. Water-based cleaning agents, hydrocarbon-based cleaning agents, alcohol-based cleaning agents such as isopropanol, glycol ether-based cleaning agents, and the like are used. However, in any case, it is not possible to satisfy all the requirements such as detergency, drying performance, safety, economic efficiency, and harmfulness for the parts where various kinds of dirt from organic to inorganic are combined and adhered. .

  Two-phase cleaning consisting of a water-immiscible organic solvent in which non-aromatic hydrocarbons and alkylated aromatic hydrocarbons are mixed, and water, for cleaning articles with various stains from organic to inorganic There has been proposed a method in which washing is performed in a state where a mechanical force is applied to the agent and dispersed in a macroemulsion state (see, for example, Patent Document 1). Also proposed is a method of emulsifying and washing by adding 1 to 10% of water to a hydrocarbon-based cleaning oil and irradiating with ultrasonic waves under reduced pressure (see, for example, Patent Document 2).

  In patent document 1, although it can wash | clean the soil from organic to inorganic by setting it as a macroemulsion, since stability of the macroemulsion of patent document 1 is very bad (separated within 30 second), it is inferior to a cleaning power. . On the other hand, in Patent Document 2, although dirt from organic to inorganic can be cleaned as in Patent Document 1, there is no limitation on the hydrocarbon-based cleaning oil to be used, and the cleaning property and the like are not particularly excellent. Further, in Patent Documents 1 and 2, since no consideration is given to draining after washing and rinsing, the water brought from the washing tank cannot be sufficiently removed even in the rinsing step, and water spots are likely to remain. have.

  On the other hand, a cleaning composition containing a hydrocarbon, a polar compound slightly soluble in water, and a water content equal to or less than the saturated water content has been proposed for cleaning articles having water-soluble soils attached thereto (for example, Patent Documents). 3). In Patent Document 3, by mixing moisture, dirt from organic to inorganic can be washed. However, since the moisture content to be blended is less than or equal to the saturated moisture content, water-soluble stains dried, especially dry The dissolving power of inorganic components contained in the water-soluble soil is not sufficient.

JP-A-1-318096 Japanese Patent Laid-Open No. 9-104992 JP 2007-283191 A

  The present invention has been made in view of the above, and is capable of cleaning a wide range of organic to inorganic soils, particularly difficult to clean soils such as dried water-soluble soils, and the generation of water spots after cleaning. An object of the present invention is to provide a cleaning method that can be suppressed and that can be used repeatedly.

  As a result of diligent research, the present inventors have found that a stable W / O macroemulsion by applying physical force to a detergent composition comprising two phases of an organic solvent (A) phase and a water (B) phase. By performing the washing process with the organic solvent (A) phase and the rinsing process, it is possible to wash a wide range of stains from organic to inorganic, and with excellent draining performance. The inventors have found a cleaning method capable of suppressing the generation of water spots and have completed the present invention.

  That is, in the cleaning method of the present invention, a W / O macroemulsion was formed by adding physical force to a cleaning composition comprising two phases of an organic solvent (A) phase and a water (B) phase. A washing process of immersing the object to be washed in a W / O macroemulsion, a washing process for immersing the article to be washed in the organic solvent (A) phase and draining after the washing process, and a draining process A rinsing step of immersing the object to be cleaned in the organic solvent (A) phase, and the organic solvent (A) phase is immersed in a stainless steel mesh having an opening of 63 μm with water attached thereto. It is characterized by removing water droplets within 5 seconds.

  Moreover, the cleaning method of the present invention is the organic solvent (A) phase which is the upper phase separated into two phases after irradiating the cleaning composition with ultrasonic waves for 2 minutes and allowing to stand for 5 minutes. The turbidity of is not less than 500 NTU.

  Further, the cleaning method of the present invention is the above invention, wherein the cleaning agent composition used in the cleaning step and the organic solvent (A) phase containing the water (B) used in the draining step differ from the specific gravity. An organic solvent (A ′) that includes a water separation step of separating the water (B) by membrane separation, electric field, centrifugal force, demulsifier, and / or adsorbent, and removing the water (B) in the water separation step ) Is reused in a washing step or a draining step.

  Moreover, the cleaning method of the present invention includes a distillation step of distilling the organic solvent (A ′) from which the water (B) has been separated in the water separation step, and the water (B) is removed in the distillation step. The removed organic solvent (A ″) is reused in a washing step or a draining step.

  In the cleaning method of the present invention, the organic solvent (A) phase is a hydrocarbon (A1) having a boiling point of 130 to 350 ° C., a boiling point of 130 to 350 ° C., and a polarity slightly soluble in water. It is a mixture of organic compounds (A2).

In the cleaning method of the present invention, in the above invention, the partition coefficient X between normal hexane and water represented by the following formula (1) of the polar organic compound (A2) is 5.0 or more. It is characterized by.
X = Co / Cw (1)
(Here, Co is the concentration (% by mass) of the polar organic compound (A2) in normal hexane, and Cw is the concentration (% by mass) of the polar organic compound (A2) in the aqueous phase).

  The cleaning method of the present invention is characterized in that, in the above invention, the hydrocarbon (A1) is one or more selected from isoparaffin, normal paraffin, cycloparaffin and terpenes.

  In the cleaning method according to the present invention, a cleaning process is performed with a cleaning composition in which a W / O macroemulsion is formed by adding physical force, and the organic solvent (A) excluding water (B) in the cleaning composition is used. By performing the draining step and the rinsing step, it is possible to clean a wide range of soils from organic to inorganic, and it is excellent in draining properties and can effectively suppress the occurrence of water spots.

  Below, the washing | cleaning method concerning this invention is demonstrated in detail.

  First, the cleaning method according to the first embodiment will be described. In the cleaning method of the present invention, a W / O macroemulsion is formed by adding physical force to a cleaning agent composition comprising two phases of an organic solvent (A) phase and a water (B) phase. A washing process for immersing the object to be washed in O macroemulsion, a washing process for immersing the article to be washed in the organic solvent (A) phase and draining, and a draining process for the organic solvent (A) The organic solvent (A) phase removes water droplets within 5 seconds when a stainless steel mesh having an opening of 63 μm with water attached is immersed in the phase. It is characterized by that.

  First, the cleaning process will be described. The cleaning composition used in the cleaning step is composed of two phases, an organic solvent (A) phase and a water (B) phase. In the cleaning step, physical force is applied to the cleaning composition separated into two phases to form a W / O macroemulsion, and the object to be cleaned is immersed in the formed W / O macroemulsion for cleaning. The physical force is applied to the cleaning composition by stirring, shaking, ultrasonic waves, air bubbling, or the like.

The cleaning step is preferably used in combination with physical forces such as stirring, shaking, ultrasonic waves, air bubbling and the like. The use conditions of the ultrasonic waves are preferably, for example, an oscillation frequency: 20 to 100 kHz and an oscillation output per 1 L of the cleaning composition: 10 to 200 W. In air bubbling, it is preferable to vent fine bubbles, preferably at a gas: detergent composition volume ratio of 1: 1 to 5: 1. Air bubbling is preferable in that dirt that does not dissolve in the cleaning composition can be raised together with bubbles and separated. Further, after immersion cleaning, cleaning by spraying may be performed. At that time, the pressure is preferably 0.5 to ¹⁰ kg / cm ² G, for example.

  Moreover, it is preferable that the detergent composition used in the washing step is excellent in emulsion stability from the viewpoint of enhancing the detergency against various stains from organic to inorganic. The emulsification stability of the cleaning composition can be judged by the turbidity of the organic solvent (A) phase after leaving the cleaning composition irradiated with ultrasonic waves under predetermined conditions. For example, the cleaning composition at 20 ° C. is irradiated with ultrasonic waves for 2 minutes (HONDA W-113, output 100 W, frequency 28 kHz), and the turbidity of the organic solvent (A) phase after standing for 5 minutes is 500 NTU or more. If present, the emulsion stability is excellent and a desired cleaning ability can be exhibited.

  Two types of cleaning compositions can be exemplified as the cleaning composition used in the cleaning process of the present invention. In the cleaning composition according to the first embodiment, as an organic solvent (A) phase, a hydrocarbon (A1) having a boiling point of 130 to 350 ° C. is slightly dissolved in 20 to 60 parts by mass and water having a boiling point of 130 to 350 ° C. It contains 40 to 80 parts by mass of a polar organic compound (A2) having no hydroxyl group, and contains water (B) at a ratio of 1.0 to 100 parts by mass with respect to 100 parts by mass in total of the organic solvent (A). .

  In the cleaning composition according to the first embodiment, 20 to 60 parts by mass of the hydrocarbon (A1) is blended. When the blending amount of the hydrocarbon (A1) exceeds 60 parts by mass, the cleaning ability with respect to the inorganic component is reduced, and conversely, when the blending amount is less than 20 parts by mass, the cleaning ability with respect to the organic component may be reduced. . It is preferable that 30-60 mass parts of hydrocarbons (A1) are blended.

  The boiling point of the hydrocarbon (A1) is 130 to 350 ° C. When the boiling point of the hydrocarbon (A1) is less than 130 ° C., the flash point is lower than room temperature, which is not preferable for safety. Further, when the boiling point of the hydrocarbon (A1) exceeds 350 ° C., it is not preferable as a cleaning agent because the cleaning agent is difficult to penetrate into the gap portion of the object to be cleaned due to high viscosity, and cleaning residue is likely to occur. Further, when the boiling point of the hydrocarbon (A1) exceeds 350 ° C., it becomes difficult to separate the organic component in the soil component from the hydrocarbon (A1) during the distillation step of the cleaning composition described later. It is not preferable. The boiling point of the hydrocarbon (A1) is preferably 150 to 330 ° C, more preferably 170 to 310 ° C.

  In the cleaning composition according to the first embodiment, the hydrocarbon (A1) having a boiling point of 130 to 350 ° C. is preferably at least one selected from isoparaffin, normal paraffin, cycloparaffin, and terpenes. As the hydrocarbon (A1), normal paraffins having 9 to 20 carbon atoms, isoparaffins having 9 to 20 carbon atoms, cycloparaffins having 9 to 20 carbon atoms, terpenes such as limonene, and the like are preferably used.

  In the cleaning composition according to the first embodiment, 40 to 80 parts by mass of the polar organic compound (A2) having no hydroxyl group is blended. When the blending amount of the polar organic compound (A2) having no hydroxyl group exceeds 80 parts by mass, the cleaning ability with respect to the organic component decreases, and conversely, when the blending amount is less than 40 parts by mass, the cleaning ability with respect to the inorganic component decreases. There is a risk. The blending amount of the polar organic compound (A2) having no hydroxyl group is preferably 40 to 70 parts by mass.

  The polar organic compound (A2) having no hydroxyl group has a boiling point of 130 to 350 ° C. When the boiling point of the polar organic compound (A2) having no hydroxyl group is less than 130 ° C., the flash point is lower than room temperature, which is not preferable for safety. Further, when the boiling point of the polar organic compound (A2) having no hydroxyl group exceeds 350 ° C., the cleaning agent is difficult to permeate into the gap portion of the object to be cleaned due to high viscosity, and cleaning residue is likely to occur. It is not preferable. Moreover, when the boiling point of the polar organic compound (A2) having no hydroxyl group exceeds 350 ° C., the organic component in the soil component and the polar organic compound having no hydroxyl group ( It is not preferable because it is difficult to separate from A2). The boiling point of the polar organic compound (A2) having no hydroxyl group is preferably 150 to 330 ° C, more preferably 170 to 310 ° C.

  The polar organic compound (A2) having no hydroxyl group is slightly soluble in water. The partition coefficient X (25 ° C.) between normal hexane and water represented by the following formula (1) of the polar organic compound (A2) having no hydroxyl group is preferably 5.0 or more.

X = Co / Cw (1)
(Here, Co is the concentration (mass%) of the polar organic compound (A2) having no hydroxyl group in normal hexane, and Cw is the concentration of the polar organic compound (A2) having no hydroxyl group in the aqueous phase)

  The polar organic compound (A2) having no hydroxyl group has a partition coefficient X at 25 ° C. of 5.0 or more, more preferably 10.0 or more. When the distribution coefficient X is less than 5.0, the polar organic compound (A2) shifts to the aqueous phase when forming a W / O macromalsion with water, and the polar organic in the cleaning composition. This is not preferable because the amount of the compound (A2) is reduced and the cleaning ability is lowered.

  The polar organic compound (A2) having no hydroxyl group is preferably at least one selected from the group consisting of ethers, ketones, aldehydes, esters, polyhydric alcohols, amines, and lactams. . Examples of these include ethers such as dibutyl ether, phenetole, 2-methylanisole, diisoamyl ether, 3-methylanisole, 4-methylanisole, and ethylbenzyl ether, and ketones include mesityl oxide, ethyl- Aldehydes such as n-butyl ketone, di-n-propyl ketone, methyl-n-amyl ketone, 2-methylcyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, methyl-n-hexyl ketone, phorone, acetophenone and the like are 2 Esters such as 1,3-dimethylpentaldehyde, tetrahydrobenzaldehyde, isophorone, etc. include ethyl isovalerate, isoamyl acetate, butyl propionate, amyl acetate, isoamyl propionate, butyl butyrate, acetic acid Chlohexyl, dimethyl malonate, isoamyl isovalerate, methyl benzoate, 2-ethylhexyl acetate, benzyl acetate, methyl salicylate, dibutyl oxalate, dimethyl phthalate, diethyl phthalate, dioctyl sebacate, dibutyl phthalate, butyl stearate, Examples of polyhydric alcohols such as dibutyl sebacate include ethylene glycol monoethyl ether acetate, 3-methoxy-3-methylbutyl acetate, ethylene glycol monobutyl ether acetate, ethyl-3-ethoxypropionate, ethylene glycol dibutyl ether, 2 -(2-ethylhexyloxy) ethanol, propylene glycol monomethyl ether propionate, diethylene glycol monobutyl ether acetate, diethylene glycol Examples of amines such as dibutyl ether include diisobutylamine, heptylamine, 2-ethylhexylamine, diamylamine, tri-1-butylamine, N, N-dibutylethanolamine, dicyclohexylamine, dioctylamine, and diphenylamine. δ-valerolactam, 1-octyl-2-pyrrolidone and the like, among which methyl-n-hexyl ketone, 3-methoxy-3-methylbutyl acetate, ethylene glycol monobutyl ether acetate, ethyl-3-ethoxypropionate, Propylene glycol monomethyl ether propionate is preferably used.

  In the cleaning composition according to the first embodiment, water (B) is blended at a ratio of 1.0 to 100 parts by mass with respect to 100 parts by mass in total of the organic solvent (A). When the blending amount of water (B) is less than 1.0 part by mass with respect to 100 parts by mass of the organic solvent (A), it is possible to satisfactorily wash dirt that is difficult to wash, for example, dried inorganic dirt. I can't. In order to remove the dried inorganic soil, it is considered that the inorganic soil must be dissolved in water droplets (macroemulsion) floating in the cleaning composition. Moreover, even if the compounding quantity of water (B) exceeds 100 mass parts with respect to a total of 100 mass parts of an organic solvent (A), since a detergency does not improve and the amount of waste water increases, it is unpreferable. In the cleaning composition according to the first embodiment, the blending amount of water (B) is preferably 2.0 to 50 parts by mass, more preferably 100 parts by mass of the total amount of the organic solvent (A). Is 3.0-30 parts by mass.

  In addition, in the case of standing, unless it separates into two phases into the organic solvent (A) phase and the water (B) phase, water (B) is used with respect to a total of 100 parts by mass of the organic solvent (A). Even if it is contained at a ratio of 1.0 to 100 parts by mass, it does not correspond to the cleaning composition according to the first embodiment of the present invention. A large amount of water (B) is added to the organic solvent (A), and the two-phase separation does not occur at the time of standing, and the water (B) and the organic solvent (A) are compatible with each other. This is because the cleaning power is inferior. The cleaning composition according to the first embodiment has a wide range of stains from organic to inorganic by forming a W / O macroemulsion by applying physical force, for example, stirring, shaking, and ultrasonic irradiation during cleaning. Can be cleaned.

  In the cleaning composition according to the second embodiment, as the organic solvent (A), hydrocarbon (A1) having a boiling point of 130 to 350 ° C. is slightly dissolved in 20 to 80 parts by mass and water having a boiling point of 130 to 350 ° C. The polar organic compound (A2) having no hydroxyl group is slightly dissolved in 10 to 78 parts by mass and water having a boiling point of 130 to 350 ° C., and the polar organic compound (A3) having a hydroxyl group is 2 to 10 parts by mass. And water (B) is included at a ratio of 1.0 to 100 parts by mass with respect to 100 parts by mass in total of the organic solvent (A).

  In the cleaning composition according to the second embodiment, 20 to 80 parts by mass of the hydrocarbon (A1) is blended. When the blending amount of the hydrocarbon (A1) exceeds 80 parts by mass, the cleaning ability with respect to the inorganic component is reduced. Conversely, when the blending amount is less than 20 parts by mass, the cleaning ability with respect to the organic component may be reduced. . It is preferable that 30-80 mass parts of hydrocarbons (A1) are blended.

  The boiling point of the hydrocarbon (A1) according to the second embodiment and the examples of the compounds used suitably are the same as those in the first embodiment.

  In the cleaning composition according to the second embodiment, 10 to 78 parts by mass of the polar organic compound (A2) having no hydroxyl group is blended. When the blending amount of the polar organic compound (A2) having no hydroxyl group exceeds 78 parts by mass, the cleaning ability with respect to the organic component decreases, and conversely, when the blending amount is less than 10 parts by mass, the cleaning ability with respect to the inorganic component decreases. There is a risk. It is preferable that the compounding quantity of the polar organic compound (A2) which does not have a hydroxyl group is 10-70 mass parts.

  The boiling point of the polar organic compound (A2) having no hydroxyl group according to the second embodiment, the concept of being slightly soluble in water, and the examples of the compounds suitably used are the same as those in the first embodiment.

  In the cleaning composition according to the second embodiment, 2 to 10 parts by mass of the polar organic compound (A3) having a hydroxyl group is blended. When the compounding amount of the polar organic compound (A3) having a hydroxyl group exceeds 10 parts by mass, a water separation property (hereinafter, “ Also called “emulsion separability”). On the other hand, when the blending amount is less than 2 parts by mass, the stability of the W / O macroemulsion (hereinafter also referred to as “emulsion stability”) decreases. It is preferable that the compounding quantity of the polar organic compound (A3) which has a hydroxyl group is 2-8 mass parts.

  The boiling point of the polar organic compound (A3) having a hydroxyl group is 130 to 350 ° C. When the boiling point of the polar organic compound (A3) having a hydroxyl group is less than 130 ° C., the flash point is lower than room temperature, which is not preferable for safety. In addition, when the boiling point of the polar organic compound (A3) having a hydroxyl group exceeds 350 ° C., it is difficult for the cleaning agent to penetrate into the gap portion of the object to be cleaned due to high viscosity, and it becomes easy to generate a cleaning residue. It is not preferable. In addition, when the boiling point of the polar organic compound (A3) having a hydroxyl group exceeds 350 ° C., the organic component in the soil component and the polar organic compound (A3) having a hydroxyl group during the distillation step of the detergent composition described later. It is not preferable because it is difficult to separate from. The boiling point of the polar organic compound (A3) having a hydroxyl group is preferably 150 to 330 ° C, more preferably 170 to 310 ° C.

  The polar organic compound (A3) having a hydroxyl group is slightly soluble in water. The partition coefficient X (25 ° C.) between normal hexane and water represented by the following formula (1) of the polar organic compound (A3) having a hydroxyl group is preferably 5.0 or more.

X = Co / Cw (1)
(Here, Co is the concentration (mass%) of the polar organic compound (A3) having a hydroxyl group in normal hexane, and Cw is the concentration of the polar organic compound (A3) having a hydroxyl group in the aqueous phase)

  The polar organic compound (A3) having a hydroxyl group has a distribution coefficient X at 25 ° C. of 5.0 or more, more preferably 10.0 or more. When the distribution coefficient X is less than 5.0, the polar organic compound (A3) shifts to the aqueous phase when forming a macro-malsion with water, and the polar organic compound (A3) in the cleaning composition. ) Is reduced, and the washing ability, emulsion stability and emulsion separation properties are reduced, which is not preferable.

  The polar organic compound (A3) having a hydroxyl group is preferably at least one selected from alcohols. Examples of these include 4-methyl-2-pentanol, 2-ethylbutanol, 1-heptanol, 2-heptanol, 3-heptanol, 1-hexanol, 2-methylcyclohexanol, 3-methylcyclohexanol, 4-methyl Cyclohexanol, 2,6-dimethyl-4-heptanol, 2-ethylhexanol, 3,5,5-trimethyl-1-hexanol, 1-octanol, 1-nonanol, benzyl alcohol, α-terpineol, 1-decanol, etc. Among them, 1-heptanol, 2-ethylhexanol, 1-octanol, and benzyl alcohol are preferably used.

  In the cleaning composition according to the second embodiment, water (B) is contained at a ratio of 1.0 to 100 parts by mass with respect to 100 parts by mass in total of the organic solvent (A). When water (B) is less than 1.0 part by mass with respect to 100 parts by mass of the organic solvent (A), it is not possible to satisfactorily wash dirt that is difficult to wash, for example, dried inorganic dirt. In order to remove the dried inorganic soil, it is considered that the inorganic soil must be dissolved in water droplets (macroemulsion) floating in the cleaning composition. Moreover, even if the compounding quantity of water (B) exceeds 100 mass parts with respect to a total of 100 mass parts of an organic solvent (A), since a detergency does not improve and the amount of waste water increases, it is unpreferable. In the cleaning composition according to the second embodiment, the blending amount of water (B) is preferably 2.0 to 50 parts by mass, more preferably 3 with respect to a total of 100 parts by mass of the organic solvent (A). 0.0 to 30 parts by mass.

  In addition, in the case of standing, unless it separates into two phases into the organic solvent (A) phase and the water (B) phase, water (B) is used with respect to a total of 100 parts by mass of the organic solvent (A). Even if it is contained at a ratio of 1.0 to 100 parts by mass, it does not correspond to the cleaning composition according to the second embodiment of the present invention. A large amount of water (B) is added to the organic solvent (A), and the two-phase separation does not occur at the time of standing, and the water (B) and the organic solvent (A) are compatible with each other. This is because the cleaning power is inferior. The cleaning composition according to the second embodiment has a wide range of stains from organic to inorganic by forming a W / O macroemulsion by applying physical force, for example, stirring, shaking, and ultrasonic irradiation during cleaning. Can be cleaned.

  Since the cleaning composition according to the first and second embodiments of the present invention is excellent in detergency emulsion stability and emulsion separability, it can be suitably used in the cleaning method of the present invention. it can. When the organic solvent (A) phase and the water (B) phase are separated by the difference in specific gravity in the washing step and the draining step described later, the first embodiment and the second embodiment are used. Although it is preferable to use such a detergent composition, when water (B) is separated by other separation methods, 60 masses of a detergent composition having slightly inferior emulsion separation, for example, hydrocarbon (A1). It is also possible to use a detergent composition containing more than part.

The density of the organic solvent (A) phase of the cleaning composition according to the first embodiment and the second embodiment of the present invention is preferably 0.95 g / cm ³ or less, more preferably. 0.70 to 0.90 g / cm ³ . When the density of the organic solvent (A) phase exceeds 0.95 g / cm ³ , the draining performance in the draining process described later is reduced, and a large amount of water is brought into the rinsing process from the draining process due to entrainment with the object to be cleaned Therefore, there is a possibility that water spots may be generated without sufficient draining even in the rinsing step.

  The pH of the water (B) phase of the cleaning composition according to the first embodiment and the second embodiment of the present invention is preferably 1.5 or less, and preferably 1.0 or less. More preferred. By setting the pH to 1.5 or less, the cleaning ability of dirt (hereinafter referred to as “smut”) adhering to the parts in the polishing process or the pressing process is remarkably improved. This is because the zeta potential of the inorganic oxide particles in the smut is positively charged by contact with the cleaning composition, and the aggregation of the inorganic oxide particles is suppressed, that is, the dispersibility of the inorganic oxide particles is improved. it is conceivable that. Moreover, there exists a secondary effect which can melt | dissolve an inorganic oxide particle by making pH into 1.5 or less.

  In order to make the pH of the aqueous (B) phase of the cleaning composition according to the first embodiment and the second embodiment of the present invention less than 1.5, an acid is added to the cleaning composition. It is preferable to do. As the acid blended in the cleaning composition, for example, any of inorganic acids such as phosphoric acid, hydrochloric acid, sulfuric acid and nitric acid and organic acids such as sulfamic acid and oxalic acid can be used.

  The cleaning composition according to the first embodiment and the second embodiment of the present invention includes other hydrocarbons and water-soluble esters within a range not impairing the object of the present invention, Conventional additives such as blending components such as alcohols, ketones and lactams, antioxidants, ultraviolet absorbers and rust inhibitors can be included. The content other than the components specified in the present invention is preferably less than 10% by mass, and particularly preferably less than 2% by mass.

  As an ultraviolet absorber and an antioxidant, it helps to improve the stability of the cleaning agent for a long period of time. As the ultraviolet absorber, for example, a benzotriazole, a benzophenone, a hindered amine, or the like can be used. Any of those that dissolve in the cleaning composition of the present invention, such as phenol, amine, sulfur, and phosphorus, can be used. It is particularly preferable to add 50 to 1000 ppm of a phenolic antioxidant.

  Next, the draining process will be described. In the draining process, the object to be cleaned is finished in the mixture of the organic solvent (A) obtained by removing water (B) from the cleaning composition according to the first embodiment or the second embodiment. Is performed by dipping. When the cleaning composition according to the first embodiment is used in the cleaning process, the cleaning composition uses the hydrocarbon (A1) and the polar organic compound (A2) having no hydroxyl group in the cleaning process. The object to be cleaned is dipped in an organic solvent (A) phase that is compatible at the same blending ratio as above. When the cleaning composition according to the second embodiment is used in the cleaning step, hydrocarbon (A1), polar organic compound (A2) having no hydroxyl group, polar organic compound (A3) having a hydroxyl group, The material to be cleaned is dipped in an organic solvent (A) phase mixed at the same mixing ratio as the cleaning composition used in the cleaning step. In the draining process, the water (B) brought in and the organic phase are quickly separated to improve draining performance. In the draining process, physical forces such as stirring, ultrasonic waves and air bubbling are added to the organic phase. Preferably not. In addition, the rocking | fluctuation of the grade which does not form a W / O macroemulsion is preferable at the point which improves draining property. The organic solvent (A) phase used in the draining step is not necessarily the same type and proportion of the organic solvent (A) phase used in the washing step, but the running cost and liquid management From the aspect, the organic solvent (A) phase is preferably of the same type and proportion as the organic solvent (A) phase used in the washing step.

  In the first cleaning method of the present invention, in order to improve the cleaning efficiency, it is preferable to quickly remove moisture from the object to be cleaned in the draining step. In order to quickly remove moisture from an object to be cleaned without adding physical force, the organic solvent (A) phase of the cleaning composition according to the first embodiment and the second embodiment, that is, An organic solvent (A) phase in which a hydrocarbon (A1) and a polar organic compound (A2) having no hydroxyl group are compatible, or a hydrocarbon (A1) and a polar organic compound (A2) having no hydroxyl group and a hydroxyl group. It is preferable that the organic solvent (A) phase in which the polar organic compound (A3) has a high drainability. The drainability of the organic solvent (A) phase can be determined by a drainability test. For example, if a stainless steel mesh with an aperture of 63 μm with water attached is immersed in the organic solvent (A) phase, if water drops can be dropped and removed within 5 seconds, it is excellent in drainage, can improve cleaning efficiency, and generate water stains. Can be suppressed.

  In the rinsing process, the object to be cleaned is completed in the mixture of the organic solvent (A) obtained by removing water (B) from the cleaning composition according to the first embodiment or the second embodiment. Is performed by dipping. When the cleaning composition according to the first embodiment is used in the cleaning process, the cleaning composition uses the hydrocarbon (A1) and the polar organic compound (A2) having no hydroxyl group in the cleaning process. The object to be cleaned is immersed in an organic solvent (A) phase that is compatible at the same blending ratio as in the rinsing step. When the cleaning composition according to the second embodiment is used in the cleaning step, hydrocarbon (A1), polar organic compound (A2) having no hydroxyl group, polar organic compound (A3) having a hydroxyl group, Is rinsed by immersing the object to be cleaned in the organic solvent (A) phase mixed in the same mixing ratio as the cleaning composition used in the cleaning process.

  When the organic phase of the draining process is strictly controlled by a distillation process or the like described later, or when the cleanliness requirement of the object to be cleaned is not so high, the rinsing process is not necessarily performed. However, in the organic solvent (A) phase adhering to the object to be cleaned in the draining process, there is a risk of contamination of each component from the cleaning process due to continuous use. If the rinsing process is not performed, Since the dirt component mixed in the organic solvent (A) phase used in the draining step may remain and cause a stain, it is preferable to perform the rinsing step. The organic solvent (A) phase used in the rinsing step is not necessarily the same type and proportion of the organic solvent (A) phase used in the washing step and draining step, but the running cost and From the viewpoint of liquid management, it is preferable that the organic solvent (A) phase has the same type and proportion as the organic solvent (A) phase used in the washing step and the draining step.

  In any of the washing step, draining step, and rinsing step, the washing time is preferably 15 seconds to 2 hours, particularly 30 seconds to 20 minutes, and an optimum time for removing dirt may be appropriately set. Moreover, the washing | cleaning temperature should just set the optimal temperature for removing a stain | pollution | contamination suitably, and 20-130 degreeC is preferable. In addition, since the saturated water content of the organic solvent (A) phase of the cleaning composition varies depending on the temperature, the cleaning temperature in the cleaning step is determined by the difference between the organic solvent (A) phase and the water (B) phase upon standing. When the two phases are separated and physical force is applied, it is preferably performed at a temperature at which a W / O macroemulsion is formed. If the organic solvent (A) phase and the water (B) phase are not separated into two phases depending on the washing temperature, water (B) may be further added.

  In a macroemulsion-based cleaning method that has been used conventionally, rinsing is performed with water after cleaning (Patent Document 1: JP-A-1-318096) or rinsing with a hydrocarbon-based cleaning oil (Patent Document 2: JP-A-9-104992). When rinsing with water after washing with a macroemulsion detergent, there are problems of oil stains and high waste liquid treatment costs. On the other hand, when the rinsing process is performed with a hydrocarbon-based cleaning oil, particularly a hydrocarbon-based cleaning oil that is not selected in consideration of drainability, water stains are likely to occur. In the cleaning method of the present invention, since the draining step and the subsequent rinsing step are performed with the organic solvent (A) phase having high drainability, the generation of water stains can be suppressed, and the organic solvent (A) of the cleaning composition can be suppressed. And the organic solvent (A) used in the subsequent draining step and rinsing step are the same, and thus the recyclability is also excellent.

  In the cleaning method of the present invention, it is preferable to perform (1) the cleaning step, (2) the draining step, and (3) the rinsing step in separate cleaning tanks, but (1) the cleaning step, (2) the draining step, Can also be performed in one washing tank. When (1) cleaning step and (2) draining step are performed in one cleaning tank, (1) cleaning was performed by applying physical force such as stirring, shaking, ultrasonic wave, air bubbling, etc. Thereafter, the supply of physical force is stopped, the cleaning composition is separated into the organic solvent (A) phase and the water (B) phase, and the object to be cleaned is immersed in the upper organic solvent (A) phase. The water draining process may be performed.

  In the cleaning method of the present invention, the specific gravity difference, membrane separation, electric field, centrifugal force, and demulsifier are obtained from the detergent composition used in the cleaning process and the organic solvent (A) phase containing water (B) used in the draining process. It is preferable to include a water separation step of separating water (B) with an adsorbent. The organic solvent (A ′) from which water (B) has been removed in the water separation process can be reused in the washing process or the draining process, and is used in the washing process in a batch process or a continuous process, and By separating water (B) from the organic solvent (A) phase containing water (B) used in the draining step, it is possible to maintain the cleaning power and drainability.

  In order to separate water (B) due to the difference in specific gravity, a water separation tank is disposed outside the washing tank or draining tank via a pipe and a pump, or the detergent composition and water (B ) Containing the organic solvent (A) is extracted and supplied to the water separation tank, and the organic solvent (A ′) from which the water (B) is separated in the water separation tank is circulated or supplied to the washing tank or draining tank. What is necessary is just to reuse the organic solvent (A ') which isolate | separated water (B). In addition, the remaining cleaning liquid can be reused after the washing tank or draining tank is left still temporarily and the lower phase water (B) is extracted.

  Examples of techniques for separating water (B) by membrane separation include JP-A-8-309351 and JP-A-5-57314. A membrane module is disposed outside the washing tank or draining tank via a pipe and a pump, or the organic solvent (A) containing the cleaning composition and water (B) is extracted from the washing tank and the draining tank and supplied to the membrane module. Then, the organic solvent (A ′) from which water (B) has been separated by the membrane module is circulated or supplied to the washing tank or draining tank, and the organic solvent (A ′) from which water (B) has been separated is reused. do it.

  Examples of techniques for separating water (B) by an electric field include Japanese Patent Application Laid-Open Nos. 2014-147913 and 2008-49267. A demulsifying device is arranged outside the washing tank or draining tank, or the organic solvent (A) containing the detergent composition and water (B) is extracted from the washing tank and draining tank and supplied to the demulsifying apparatus to demulsify. The organic solvent (A ') from which water (B) has been separated by the apparatus is circulated or supplied to the washing tank or draining tank, and the organic solvent (A') from which water (B) has been separated may be reused. . Alternatively, the remaining cleaning liquid can be reused after the water (B), which has been temporarily left in a washing tank or a draining tank and applied with an electric field to be combined and settled, is extracted.

  Examples of techniques for separating water (B) by centrifugation include JP-A-5-57314, JP-A-11-137906, JP-A-10-273693, and JP-A-8-92571. be able to. A centrifuge is disposed outside the washing tank or draining tank via a pipe and a pump, or the organic solvent (A) containing the detergent composition and water (B) is extracted from the washing tank and the draining tank, and then the centrifuge. Organic solvent (A ') from which water (B) was separated by supplying water to the washing tank or draining tank by circulating or supplying the organic solvent (A') from which water (B) was separated by a centrifuge Can be reused.

  Examples of techniques for separating water (B) with a demulsifier include JP 2004-049936 A, JP 11-137906 A, JP 9-217072 A, JP 9-208957 A, and the like. be able to. The organic solvent (A) containing the cleaning composition and water (B) was extracted from the washing tank and draining tank and supplied to the water separation tank, and the demulsifier was supplied into the water separation tank to separate the water (B). What is necessary is just to reuse the organic solvent (A ') which supplied the organic solvent (A') to the washing tank or the draining tank, and isolate | separated water (B). In addition, the remaining washing solution can be reused after the washing tank or draining tank is temporarily left and the demulsifier is added to remove the water (B) which has been combined and settled.

  In order to separate the water (B) by the adsorbent, a module filled with an adsorbent such as activated carbon is disposed outside the washing tank or draining tank via a pipe and a pump, or the cleaning agent is removed from the washing tank and the draining tank. The organic solvent (A) containing the composition and water (B) is extracted and supplied to the adsorbent module, and the organic solvent (A ′) from which water (B) has been separated by the adsorbent module is supplied to a washing tank or a draining tank. The organic solvent (A ′) from which water (B) is separated by circulation or supply may be reused.

  In addition, water (B) can be removed from the cleaning composition and the organic solvent (A) containing water (B) by extraction, nonionic surfactant, flotation separation, sedimentation separation using a flocculant, or the like. Good. When the organic solvent (A ′) from which water (B) has been separated in the water separation step is reused in the washing step, water (B) is appropriately used up to a rate at which a W / O macroemulsion is formed by physical force. It is preferable to add and use.

  The organic solvent (A ′) from which water (B) has been removed by the above method may be used as it is in a washing tank or a draining tank. However, in order to remove the introduced dirt, water ( The organic solvent (A ′) from which B) has been separated is preferably distilled by a distillation step. The organic component in the dirt adhered to the object to be cleaned is dissolved in the organic solvent (A) and the organic solvent (A ′) phase, and the inorganic component is dissolved in the water (B) phase. In order to remove the inorganic component of the soil, the water (B) containing the soil may be separated in the water separation step, and the organic component of the soil dissolved in the organic solvent (A) and the organic solvent (A ′) phase. Is separated from the organic component (A ″) by distillation because the organic component in the soil is low in volatility. The organic solvent (A ″) can be separated from the organic components in the low-volatility dirt by distillation, which makes it possible to reduce the amount of waste discharged out of the system and to have high cleanliness. The organic solvent (A ″) can be recovered.

  The distillation step is carried out in batch by taking out the organic solvent (A ′) from which the water (B) has been separated by the water separator, and downstream of the water separator connected to a washing tank and a draining tank via a pipe. It is also possible to perform distillation of the cleaning composition and the like continuously. The detergent composition from which dirt has been removed by the distillation step may be reused in the washing step, draining step, and rinsing step. In addition, when reusing in a washing | cleaning process, it is preferable to add and use water (B) suitably to the ratio which forms a W / O macroemulsion with a physical force.

  Hereinafter, although the washing | cleaning method concerning this invention is demonstrated still in detail by an Example and a comparative example, the washing | cleaning method of this invention is limited and interpreted by the following Example.

(1) Partition coefficient X of polar organic compound (A2) having no hydroxyl group and polar organic compound (A3) having a hydroxyl group
The partition coefficient X of the polar organic compound (A2) having no hydroxyl group and the polar organic compound (A3) having a hydroxyl group shown in Table 1 was measured. The distribution coefficient X is calculated by adding 100 parts by weight of distilled water to a composition in which 80 parts by weight of normal hexane and 20 parts by weight of a polar organic compound are mixed at 25 ° C., shaking well, and then allowing to stand for 1 hour. , Separated into a normal hexane phase and an aqueous phase. The amount of the polar organic compound in the normal hexane phase was quantified by gas chromatography, and the distribution coefficient X was calculated. The results are shown in Table 1.

(2) Cleaning test 1
A water-soluble cutting oil (Unix CS made by JX Energy) was diluted 10 times with distilled water to prepare a 10% by mass aqueous solution, and the nail wave retainer was immersed in 10% by mass of the water-soluble cutting oil for 1 minute, The product was taken out and dried at 40 ° C. for 3 hours, and a water-soluble cutting oil was adhered to the product to be cleaned. The amount of dirt adhered was approximately 15 mg / piece. 70 to 100 mL of the cleaning composition is put in a 100 mL beaker, one of the objects to be cleaned previously adjusted is immersed therein, and an ultrasonic cleaner (HONDA W-113, output 100 W, frequency 28 kHz) is used at 20 ° C. 3 for 3 minutes (cleaning process). After the cleaning process, a water draining process for the object to be cleaned was performed. In the draining step, the organic solvent (A) phase not containing water (B) of the cleaning composition used in the cleaning step is poured into another 100 mL beaker, and the organic solvent (A) phase is cleaned after the cleaning step. Was dipped while rocking for 30 seconds to perform a draining process. After the draining process, the object to be cleaned was rinsed. In the rinsing step, the organic solvent (A) phase not containing water (B) of the cleaning composition used in the washing step is poured into another 100 mL beaker, and the organic solvent (A) phase is washed after the draining step. Was immersed for 30 seconds while oscillating for 30 seconds. Then, it dried at 80 degreeC for 2 hours. The amount of oil adhering to the object to be cleaned after drying was measured. In the evaluation of the cleaning property, the amount of oil adhering to the object to be cleaned is less than 1.0 mg / piece, and the 1.0 mg / piece or more is ×.

(3) Cleaning test 2
Dilute the water-soluble cutting oil (JX Energy Unisolvable CS) used in Cleaning Test 1 twice with distilled water to prepare a 50% by weight aqueous solution. A washed product was used. The amount of adhesion was approximately 80 mg / piece. This object to be cleaned was cleaned in the same process as in cleaning test 1. The evaluation of the cleaning property is the same as that of the cleaning test 1.

(4) Cleaning test 3
A SUS430 workpiece was subjected to barrel polishing, and a black smut adhered to the surface was used as an object to be cleaned. This object to be cleaned was cleaned in the same process as in cleaning test 1 (drying was at 70 ° C. for 20 minutes). Evaluation of the cleaning property was made by visual observation of no residue (◯), slight residue (Δ), and remarkable residue (×) on the workpiece.

(5) Cleaning test 4
Edible rapeseed oil (manufactured by Nissin) was dropped onto a stainless steel plate, heated at 140 ° C. for 6 hours, and then allowed to cool at room temperature, to be washed. This object to be cleaned was cleaned in the same process as in cleaning test 1 (drying was at 70 ° C. for 20 minutes). In the evaluation of the cleaning property, there was no residue on the workpiece (◯), there was a small amount of residue (Δ), and there was a remarkable residue (×).

(6) Cleaning test 5
An object to be cleaned was prepared by attaching a fingerprint to a slide glass and allowing it to stand at room temperature for 30 minutes. This object to be cleaned was cleaned in the same process as the cleaning test 1 (cleaning process, 25 ° C., 1 minute, drying was 70 ° C., 20 minutes). In the evaluation of the cleaning property, there was no residue on the workpiece (◯), there was a small amount of residue (Δ), and there was a remarkable residue (×).

(7) Coating test In washing test 3, DLC (diamond-like carbon) coating was performed on a workpiece having no smut residue (evaluation was good), and the appearance was visually observed. The case where there was no pinhole or film peeling was marked with ◯, and the case where there was a pinhole or film peeling was marked with x.

(8) Emulsification stability test The following test was done about the emulsion stability of the cleaning composition concerning this invention. Hydrocarbon (A1) and polar organic compound (A2) having no hydroxyl group, or hydrocarbon (A1), polar organic compound (A2) having no hydroxyl group, and polar organic compound having a hydroxyl group blended in a predetermined ratio in a 100 mL glass bottle (A3) 80 g and 8 g of water (B) were added, and after shaking well by hand, using an ultrasonic cleaner (HONDA W-113, output 100 W, frequency 28 kHz) at 20 ° C. for 2 minutes. Irradiation was performed. Measure the turbidity of the upper organic phase after standing at room temperature for 5 minutes. If the turbidity is 500 NTU or more, ○ (the stability of the W / O macroemulsion is high), after standing at room temperature for 5 minutes If the turbidity of the organic solvent (A) phase of the upper phase was less than 500 NTU, it was judged as x (the stability of the W / O macroemulsion was low). Turbidity was measured using a turbidimeter (trade name: portable turbidimeter type 2100P, manufacturer: Central Science Co., Ltd.).

(9) Drainability test The following test was done about the drainability of the cleaning composition concerning this invention. A stainless mesh (3 cm × 3 cm, opening 63 μm) is immersed in distilled water and taken out, and used as a sample for drainage test. A hydrocarbon (A1) and a polar organic compound (A2) having no hydroxyl group, or a hydrocarbon (A1), a polar organic compound (A2) having no hydroxyl group, and a polar organic compound (A3) having a hydroxyl group, blended at a predetermined ratio A mixture of 80 g and 8 g of water (B) was subjected to ultrasonic irradiation for 2 minutes at 20 ° C. using an ultrasonic cleaner (HONDA W-113, output 100 W, frequency 28 kHz), and left at room temperature for 1 day. The upper organic solvent (A) phase after placement is used for the drainage test. The previously prepared stainless steel mesh was immersed vertically in the organic solvent (A) phase, and the time until the water adhering to the mesh surface became a ball and finished dropping was measured. It was judged as ○ when the water had finished falling within 5 seconds, or × when the water had not finished falling within 5 seconds.

(Examples 1-3)
Using 100 mL glass bottle, 40.0 parts by mass of normal dodecane as hydrocarbon (A1), 60.0 parts by mass of 3-methoxy-3-methylbutyl acetate as polar organic compound (A2) having no hydroxyl group, water (B) A cleaning composition comprising a predetermined part by weight of distilled water was prepared. After the detergent composition was shaken by hand, the entire amount was transferred to a 100 mL beaker, and as a result of washing test 1 and washing test 2, the amount of oil adhering to the washed object was 1.0 mg / piece. The cleaning was performed well. Further, cleaning test 3, cleaning test 4 and cleaning test 5 were performed. In all cases, the residue after washing was “none” or “slightly”, and the washing was performed well.

(Comparative Examples 1-2)
Using 100 mL glass bottle, 40.0 parts by mass of normal dodecane as hydrocarbon (A1), 60.0 parts by mass of 3-methoxy-3-methylbutyl acetate as polar organic compound (A2) having no hydroxyl group, water (B) A cleaning composition comprising a predetermined part by weight of distilled water was prepared. After the detergent composition was shaken and mixed by hand, the whole amount was transferred to a 100 mL beaker, and washing tests 1 to 5 were performed. The detergent composition was one phase and no W / O macroemulsion was formed.

(Comparative Examples 3-5)
Using a 100 mL glass bottle, 80.0 parts by mass of normal decane as hydrocarbon (A1), 20.0 parts by mass of 3-methoxy-3-methylbutyl acetate as polar organic compound (A2) having no hydroxyl group, water (B) A cleaning composition comprising a predetermined part by weight of distilled water was prepared. After the detergent composition was shaken and mixed by hand, the whole amount was transferred to a 100 mL beaker, and washing tests 1 to 5 were performed. The cleaning composition of Comparative Example 3 had a water drainage test result of x. Comparative Examples 4 and 5 were one phase and no W / O macroemulsion was formed. All of the comparative examples were confirmed to have low detergency.

(Examples 4 to 10)
Using a 100 mL glass bottle, 40 parts by mass of normal dodecane as hydrocarbon (A1), 60 parts by mass of 3-methoxy-3-methylbutyl acetate as polar organic compound (A2) having no hydroxyl group, and phosphoric acid as water (B) A cleaning composition comprising 17.6 parts by weight of distilled water added to a predetermined pH was prepared. After the detergent composition was shaken and mixed by hand, the whole amount was transferred to a 100 mL beaker, and washing tests 1 to 5 were performed. In addition, it was confirmed that the lower the pH, the better the cleaning performance of the smut after barrel polishing in the cleaning test 3. Furthermore, DLC coating was performed on the workpieces (Examples 8 to 10) having no residue in the cleaning test 3. The coating film was well coated with no pinholes or film peeling. The pH of the water used for the preparation of the cleaning agent was measured with a pH meter.

(Example 11)
Using a 100 mL glass bottle, 70.0 parts by mass of normal decane as hydrocarbon (A1), 20.0 parts by mass of 3-methoxy-3-methylbutyl acetate as a polar organic compound (A2) having no hydroxyl group, and polarity having a hydroxyl group A cleaning composition comprising 10.0 parts by mass of 2-ethylhexanol as the organic compound (A3) and 17.6 parts by mass of distilled water as the water (B) was prepared. After the detergent composition was shaken and mixed by hand, the whole amount was transferred to a 100 mL beaker, and washing tests 1 to 5 were performed.

Example 12
Using a 100 mL glass bottle, 70.0 parts by weight of normal decane as hydrocarbon (A1), 28.0 parts by weight of 3-methoxy-3-methylbutylacetate as a polar organic compound (A2) having no hydroxyl group, polar having a hydroxyl group A cleaning composition comprising 2.0 parts by mass of 2-ethylhexanol as the organic compound (A3) and 17.6 parts by mass of distilled water as the water (B) was prepared. After the detergent composition was shaken and mixed by hand, the whole amount was transferred to a 100 mL beaker, and washing tests 1 to 5 were performed.

(Comparative Example 6)
Using a 100 mL glass bottle, 80.0 parts by mass of normal decane as the hydrocarbon (A1), 20.0 parts by mass of 2-ethylhexanol as the polar organic compound (A3) having a hydroxyl group, and 17.6 distilled water as the water (B). A cleaning composition comprising parts by mass was prepared. After the detergent composition was shaken and mixed by hand, the whole amount was transferred to a 100 mL beaker, and washing tests 1 to 5 were performed. As a result of the drainage test, this cleaning composition was evaluated as x, and it was confirmed that the cleaning composition was inferior in cleaning performance.

(Comparative Examples 7-11, Examples 13-42)
Types and blending ratios of the hydrocarbon (A1) and the polar organic compound (A2) having no hydroxyl group, or the hydrocarbon (A1), the polar organic compound (A2) having no hydroxyl group, and the polar organic compound (A3) having a hydroxyl group The type and blending ratio were changed, and an emulsification stability test, a water separability test, and a drainage test were performed on the organic phase not blended with water (B). The test results are shown in Tables 5 to 11.

  From the results of Comparative Examples 7 to 11 and Examples 13 to 42, the mixing ratio of the hydrocarbon (A1) and the polar organic compound (A2) having no hydroxyl group in the cleaning composition according to the first embodiment of the present invention. Or when the blending ratio of the hydrocarbon (A1), the polar organic compound (A2) having no hydroxyl group and the polar organic compound (A3) having a hydroxyl group in the cleaning composition according to the second embodiment is not satisfied. It was confirmed that even if the stability was good, the drainage property was not satisfied.

  The cleaning method of the present invention is applied to parts handled in various industrial fields such as automobiles, machines, precision instruments, electricity, electronics, optics, pipes and devices of various factories such as oil refineries and chemical plants, automobiles and industrial machines, etc. It is useful for cleaning disassembled parts, various products such as metal products and resin products used in daily life, and is suitably used for smut cleaning after polishing process and pressing process. It is suitable as a cleaning method for DLC coatings that require cleanliness.

Claims (7)

A W / O macroemulsion is formed by applying physical force to a detergent composition comprising two phases of an organic solvent (A) phase and a water (B) phase, and the object to be cleaned is formed on the formed W / O macroemulsion. A cleaning process of immersing and cleaning,
After the washing step, a draining step of immersing the object to be washed in the organic solvent (A) phase and draining it;
After the draining step, a rinsing step of immersing the object to be cleaned in the organic solvent (A) phase;
Including
The organic solvent (A) phase is a cleaning method characterized by removing water droplets within 5 seconds when a stainless mesh having an opening of 63 μm with water attached is immersed.   The cleaning composition is irradiated with ultrasonic waves for 2 minutes and allowed to stand for 5 minutes, and then the turbidity of the organic solvent (A) phase, which is the upper phase separated into two phases, is 500 NTU or more. The cleaning method according to claim 1. From the organic solvent (A) phase containing the detergent composition used in the washing step and the water (B) used in the draining step, specific gravity difference, membrane separation, electric field, centrifugal force, demulsifier, and A water separation step of separating the water (B) with an adsorbent,
The cleaning method according to claim 1 or 2, wherein the organic solvent (A ') from which the water (B) has been removed in the water separation step is reused in a cleaning step or a draining step. A distillation step of distilling the organic solvent (A ′) from which the water (B) has been separated in the water separation step,
The cleaning method according to claim 3, wherein the organic solvent (A ″) from which the water (B) has been removed in the distillation step is reused in a cleaning step or a draining step.   The organic solvent (A) phase is a mixture of hydrocarbon (A1) having a boiling point of 130 to 350 ° C. and polar organic compound (A2) having a boiling point of 130 to 350 ° C. and slightly soluble in water. The cleaning method according to any one of claims 1 to 4. 6. The cleaning method according to claim 5, wherein a partition coefficient X between normal hexane and water represented by the following formula (1) of the polar organic compound (A2) is 5.0 or more.
X = Co / Cw (1)
(Here, Co is the concentration (% by mass) of the polar organic compound (A2) in normal hexane, and Cw is the concentration (% by mass) of the polar organic compound (A2) in the aqueous phase).   The cleaning method according to claim 5 or 6, wherein the hydrocarbon (A1) is at least one selected from isoparaffin, normal paraffin, cycloparaffin, and terpenes.