JP5458583B2 - How to remove water-soluble dirt - Google Patents

Description

  The present invention relates to a cleaning agent and a cleaning method for removing attached dirt such as water-soluble processing oils and inorganic substances of processed parts and products in various industrial fields such as automobiles, machines, precision equipment, electricity, and electronics. The present invention relates to a cleaning method that can quickly remove water-soluble processing oil and dirt, inorganic salts, foreign matters, and the like that are dried, and that can be repeatedly washed while separating dirt components from a cleaning agent.

  Parts used in various industrial fields such as automobiles, machinery, precision equipment, electricity, electronics, etc. use various processing oils during their processing, but they are water-soluble with high cooling properties, mainly for cutting and grinding. Many processing oils are used. Water-based cleaning agents and hydrocarbon-based cleaning agents are used to clean parts with these water-soluble processing oils after processing, but they are sufficient in terms of cleaning properties, drying properties, and reusability of cleaning agents. There is no satisfactory cleaning system.

  Since the water-based cleaning agent contains a surfactant, etc., it is necessary to rinse thoroughly with pure water after cleaning.Therefore, stains and rust are easily generated on the object to be cleaned, etc., and the cleaning equipment becomes large. There are many problems such as the necessity of ancillary equipment such as pure water production equipment and wastewater treatment equipment.

  When water-soluble processing oil has dried in the method of immersing parts in a hydrocarbon-based water displacement agent to separate and remove moisture, and then rinsing and drying the water displacement agent with a hydrocarbon-based cleaning agent There is a problem in that dirt cannot be removed because water cannot be replaced.

  In the method of adding an appropriate amount of hydrocarbon-based cleaning oil and water to the cleaning tank and washing them in a mixed state, not only the cleaning performance is insufficient, but also water droplets are likely to remain on the surface of the object to be cleaned after drying. There is a problem that water spots occur later (see, for example, Patent Document 1).

  In the case of detergents containing water and surfactants in hydrocarbon solvents to make W / O emulsions, the W / O emulsion is stable. There is a problem that not only the amount of the cleaning agent is increased, but also the disposal process is time-consuming (for example, see Patent Document 2).

Japanese Patent Laid-Open No. 9-104992 (Claim 1) JP-A-7-268394 (Claim 1)

  It is an object of the present invention to provide a cleaning agent and a cleaning system that are highly effective for removing water-soluble dirt such as dry water-soluble cutting oil and that can be repeatedly washed while separating the water-soluble dirt from the cleaning agent. .

  In view of such circumstances, the present inventors have conducted various studies to solve the above-mentioned problems, and as a result, have found the intended cleaning agent and cleaning system and have completed the present invention.

  That is, 0.05 to 2% by weight of monocarboxylic acid having 6 to 16 carbon atoms, 0.05 to 2% by weight of monoalkylamine having 6 to 16 carbon atoms, and 99.9 to 94% by weight of hydrocarbon having 10 to 14 carbon atoms. W / O emulsion type hydrocarbon cleaning agent and W / O emulsion type carbonization consisting of 100 parts by volume of hydrocarbon-based cleaning liquid and 10 to 100 parts by volume of water. After cleaning the object to be cleaned with a hydrogen-based cleaning agent, the layers are separated in a stationary state, the aqueous layer is extracted, and a cleaning process in which the hydrocarbon-based cleaning agent is repeatedly used, and the object to be cleaned after cleaning is a hydrocarbon-based one. The present invention relates to a cleaning system comprising a rinsing step 1 for rinsing with a cleaning liquid and a rinsing step 2 for rinsing an object to be cleaned with a hydrocarbon having 10 to 14 carbon atoms blended in a hydrocarbon-based cleaning liquid. .

  Hereinafter, the present invention will be described in more detail.

  In the present invention, the W / O emulsion (water-in-oil emulsion) means a system in which water droplets are dispersed in a hydrocarbon liquid, and is an opaque white turbid liquid. In addition, W / O emulsion layer separation means that the W / O emulsion layer shrinks and the transparent water layer and hydrocarbon layer increase due to coalescence of water droplets and sedimentation due to the specific gravity difference between the water droplets and hydrocarbons. This means that the upper layer (hydrocarbon) and the lower layer (water) are separated into two layers.

  The monocarboxylic acid having 6 to 16 carbon atoms used in the present invention is not particularly limited, but n-caproic acid, isocaproic acid, 2-ethyl-1-butanoic acid, 2-methyl-1-pentanoic acid, 3-methyl-1-pentanoic acid, 4-methyl-1-pentanoic acid, n-heptanoic acid, n-caprylic acid, 2-ethylhexanoic acid, 2-n-propyl-1-pentanoic acid, n-nonanoic acid, Examples include n-capric acid, n-undecanoic acid, n-dodecylic acid, n-tetradecanoic acid, n-hexadecanoic acid and the like.

  Further, the monoalkylamine having 6 to 16 carbon atoms is not particularly limited, but n-hexylamine, n-heptylamine, n-octylamine, 2-aminooctane, 2-ethylhexylamine, 1,5 -Dimethylhexylamine, n-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tetradecylamine, n-hexadecylamine and the like.

  When the carbon number of the monocarboxylic acid and monoalkylamine used in the present invention is smaller than 6, not only a sufficient cleaning effect cannot be obtained due to high water solubility, but also the performance deterioration of the hydrocarbon-based cleaning agent is accelerated. There's a problem. Also, when the carbon number of monocarboxylic acid and monoalkylamine is larger than 16, sufficient cleaning effect cannot be obtained.

  The content of the monocarboxylic acid and monoalkylamine in the hydrocarbon-based cleaning liquid of the present invention is 0.05% by weight or more and 2% by weight or less, preferably 0.1% by weight or more and 1% by weight, respectively. Less than% by weight. When the content is less than 0.05% by weight, not only a sufficient cleaning effect cannot be obtained, but also the formation of a W / O emulsion becomes difficult. Even if the content exceeds 2% by weight, no further improvement of the cleaning effect can be expected, and there is a problem that they are precipitated from hydrocarbons and the W / O emulsion is easily stabilized. Moreover, the blending amount of the monoalkylamine with respect to the monocarboxylic acid is preferably 0.5 to 1.5 in terms of molar ratio. If the blending ratio is deviated, the cleaning effect gradually decreases.

  As the hydrocarbon used in the present invention, those having 10 to 14 carbon atoms can be suitably used. A carbon number of 9 or less is not preferable because the flash point is low and the danger increases. Further, those having 15 or more carbon atoms are not preferable because they have a high freezing point and are likely to be solidified, and because the specific gravity and viscosity are high, the W / O emulsion is easily stabilized.

  The hydrocarbon used in the present invention is not particularly limited, but n-decane, 3,4-diethylhexane, 2,6-dimethyloctane, 3,3-dimethyloctane, 3,5-dimethyloctane, 4 , 4-dimethyloctane, 3-ethyl-3-methylheptane, 2-methylnonane, 3-methylnonane, 4-methylnonane, 5-methylnonane, n-undecane, n-dodecane, 2-methylundecane, 3-methylundecane, 2 , 2,4,6,6-pentamethylheptane, saturated aliphatic hydrocarbons such as n-tridecane, alicyclic hydrocarbons such as 4-methyl-1-isopropylcyclohexane, decalin, diethylbenzene, diisopropylbenzene, 1-pentyl Aromatic hydrocarbons such as benzene can be mentioned.

  In the W / O emulsion formed using the hydrocarbon-based cleaning agent of the present invention, when the physical force is stopped, the destruction of the W / O emulsion gradually proceeds and the layer is separated into a hydrocarbon layer and an aqueous layer. The time required for the W / O emulsion layer to disappear and separate into two layers is usually 16 hours or less, preferably 8 hours or less. Depending on the components and composition of the hydrocarbon-based cleaning agent, an emulsion layer may remain slightly in the middle of the two separated layers, or water droplets may remain on the hydrocarbon layer and become transparent. On the other hand, as long as 90% by volume or more of water is separated as an aqueous layer, it does not depart from the spirit of the present invention.

  In the hydrocarbon-based cleaning liquid of the present invention, a nonionic surfactant may be added within a range not departing from the characteristics of the present invention, and by this addition, a uniform W / O emulsion is formed with a smaller physical force. be able to. The amount of the nonionic surfactant added is generally 2% by weight or less based on the hydrocarbon used in the present invention, although it depends on the type. A large amount of nonionic surfactant stabilizes the W / O emulsion, resulting in a sufficient separation of the aqueous layer, for example, the layer separation rate becomes slow and the disappearance of the W / O emulsion layer becomes insufficient. become unable.

  Nonionic surfactants include, for example, polyoxyalkylene alkyl phenyl ether, polyoxyalkylene alkyl ether, polyoxyalkylene fatty acid ester, sorbitan fatty acid ester, polyoxyalkylene sorbitan fatty acid ester, and the like. Examples of the constituent oxide include ethylene oxide and propylene oxide. These nonionic surfactants can be used singly or in combination of two or more, but the HLB value (hydrophilic / lipophilic balance value) is 10 or less, preferably 3 to 10, Those which can be dissolved in the hydrocarbon used in the invention and which do not gel when water is added to give physical force can be preferably used.

  Water is added to the hydrocarbon-based cleaning liquid of the present invention, and physical strength is applied to clean the article to be cleaned in a state where a W / O emulsion is formed. The mixing ratio of water is 10 to 100 parts by volume, preferably 10 to 50 parts by volume, with respect to 100 parts by volume of the hydrocarbon-based cleaning liquid. If the amount of water is less than 10 parts by volume, the detergency may be deteriorated. If the amount exceeds 100 parts by volume, the cleaning effect is not improved, and the formation of a W / O emulsion gradually becomes difficult.

  The hydrocarbon-based detergent of the present invention includes alcohols such as butanol, hexanol, octanol, decanol, and dodecanol, diethylene glycol alkyl ethers, propylene glycol alkyl ethers, and dipropylene glycol alkyl ether without departing from the characteristics of the present invention. , Glycol ethers such as 3-methyl-3-methoxybutanol, 2,6-di-tert-butyl-p-cresol, thymol, methoxyphenol, n-propyl gallate, antioxidants such as hydroquinone, benzo Corrosion inhibitors such as triazole, tolyltriazole, and imidazoles may be added.

  In addition, although it does not specifically limit as water, Ion exchange water, distilled water, tap water, etc. can be used, even if alcohol, glycol ether, inorganic salts, etc. are contained, detergency and layer separation It can be used as long as it does not inhibit the sex. Furthermore, the W / O emulsion formed with the hydrocarbon-based cleaning agent of the present invention does not cause problems such as rusting even when an iron-based object to be cleaned is cleaned. The reason for this is not theoretically obvious, but it is considered that monocarboxylic acid or monoalkylamine is adsorbed on the object to be cleaned, and water does not directly contact the object to be cleaned, or the contact time is extremely short.

  Means for adding water to the hydrocarbon-based cleaning liquid of the present invention to give physical force to form a W / O emulsion include, for example, ultrasonic irradiation with an ultrasonic transmitter, stirring with a stirrer or homogenizer, and liquid with a pump. Examples include circulation. These may be used in combination according to the size of the washing tank.

  The cleaning method using the hydrocarbon-based cleaning agent of the present invention is not particularly limited. For example, ultrasonic cleaning, jet cleaning, immersion cleaning, rocking cleaning, rotary cleaning, shower cleaning, etc. can be used. In consideration of required cleanliness, required time, etc., these can be used alone or in combination of several types.

  When washing the object to be washed, which is dried with the hydrocarbon-based cleaning agent of the present invention and having a water-soluble processing oil attached thereto, the dirt component dissolves in the aqueous layer. It can be washed repeatedly by extracting only the layer and adding fresh water.

  The cleaning system of the present invention includes a cleaning step using the W / O emulsion, a rinsing step 1 for rinsing an object to be cleaned after washing with the hydrocarbon-based cleaning liquid of the present invention, and removing the W / O emulsion. It is characterized by comprising a rinsing step 2 in which the object to be cleaned is rinsed with the hydrocarbon to be used and the hydrocarbon-based cleaning liquid is removed.

  Since the hydrocarbon-based cleaning agent of the present invention does not form a W / O emulsion unless physical force is applied, it is effective by immersing the object to be cleaned after rinsing in the rinsing step 1 and shaking it. It is possible to remove the W / O emulsion. Furthermore, by rinsing the object to be cleaned in the rinsing step 2 with a hydrocarbon that is a component of the hydrocarbon-based cleaning liquid, it is possible to remove monoalkylamines, monocarboxylic acids, etc. contained in the hydrocarbon-based cleaning liquid, It is possible to clean things very cleanly. In each rinsing process, the cleaning liquid from the previous process is brought into the object to be cleaned, but since there is little change in the cleaning liquid composition and performance of each process, it is possible to repeatedly perform cleaning without replacing the cleaning liquid. is there.

  The objects to be cleaned after washing and rinsing should be dried using conventional hydrocarbon cleaning agents such as hot air drying, suction drying, rotary drying, vacuum drying, vapor drying, and substitution drying with nonflammable low boiling point solvents. Can be implemented.

  The hydrocarbon-based cleaning agent and cleaning system of the present invention have high removability to dry water-soluble processing oils, inorganic salts, foreign matters, etc., and can be cleaned without generation of stains or rust. Dirt can be easily separated from the agent and can be repeatedly washed.

It is the block diagram which showed the washing | cleaning system of this invention.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these.

Examples 1-18, Comparative Examples 1-16
A hydrocarbon-based cleaning agent having each composition was prepared, and the following cleaning test and layer separation test were performed. Tables 1 and 2 show the composition of the cleaning solution subjected to the test, the water addition ratio, and the test results.

<Cleaning test>
A SUS plate prepared by adding 10 times by weight of ion exchange water to the following water-soluble processing oil stock solutions (A, B) and powder (C) to prepare a water-soluble processing oil and a powder dispersion, and adhering them. What was dried for 16 hours with a dryer at 80 ° C. was used as a test piece in the washing test. Put a predetermined amount of hydrocarbon-based cleaning liquid and ion-exchanged water into a 500 ml beaker, and ultrasonically clean the test piece by immersing the test piece in a state where physical force is applied using an ultrasonic cleaner (38 kHz, 200 W). After drying, the surface was observed and the cleaning property was evaluated.

Water-soluble processing oil stock solution and powder A: Brassocut 2000U (cutting oil manufactured by Brother Swiss Lube)
B: Graindex 10 (Cutting oil manufactured by Brother Swiss Rube)
C: White fused alumina for JIS test (average powder diameter 2 μm, Japan Powder Industry Technical Association)
Washing conditions Washing temperature: Room temperature Washing time: 15 seconds Detergency evaluation ○: No stain △: Slightly remains ×: Stain remains entirely <Layer separation test>
The hydrocarbon-based detergent after the washing test was transferred to a 500 ml graduated cylinder and allowed to stand at room temperature. The state where the layers were separated after 8 hours was observed.

Evaluation of layer separation ○: Both upper and lower layers are transparent ×: Upper layer is cloudy, lower layer is cloudy, or intermediate layer is formed

1: Cleaning tank (W / O emulsion type cleaning agent of hydrocarbon cleaning liquid and water)
2: Rinse tank 1 (hydrocarbon cleaning liquid)
3: Rinse tank 2 (hydrocarbon)
4: Vacuum still 5: Ultrasonic oscillator 6: Dryer

Claims (4)

C6-C16 monocarboxylic acid 0.05-2 wt%, C6-C16 monoalkylamine 0.05-2 wt%, C10-C14 hydrocarbon 99.9-94 wt%, A W / O emulsion type hydrocarbon-based cleaning agent comprising 100 parts by volume of a hydrocarbon-based cleaning liquid comprising 2% by weight or less of a nonionic surfactant and 10 to 100 parts by volume of water. 2. The W / O emulsion according to claim 1, wherein when the W / O emulsion is allowed to stand, the hydrocarbon layer and the aqueous layer are separated into two layers, and the layer separation time is 16 hours or less. Type hydrocarbon cleaner. The object to be cleaned is washed with the W / O emulsion type hydrocarbon cleaning agent according to claim 1 or 2, and then separated into layers in a standing state, the aqueous layer is extracted, and the hydrocarbon cleaning agent is repeatedly used. A cleaning method characterized by the above. A cleaning step of cleaning the object to be cleaned with the W / O emulsion type hydrocarbon-based cleaning agent according to claim 1 or 2, and the object to be cleaned after the cleaning is a monocarboxylic acid having 6 to 16 carbon atoms 0.05 to 2 Carbonized comprising 0.05% to 2% by weight of monoalkylamine having 6 to 16 carbon atoms, 99.9 to 94% by weight of hydrocarbon having 10 to 14 carbon atoms, and 2% by weight or less of nonionic surfactant cleaning method of the rinsing step 1 of rinsing by the hydrogen-based cleaning solution, characterized in that it consists rinsing step 2 rinse the object to be cleaned by the hydrocarbons 10 to 14 carbon atoms.

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