JP6120470B2 - Wet paint booth circulating water treatment agent and treatment method - Google Patents

Description

  The present invention relates to a treatment agent and a treatment method for circulating water in a wet paint booth. More specifically, the present invention relates to a treatment agent and a treatment method for wet paint booth circulating water containing a specific α-chlorobenzaldoxime compound, which exhibits an excellent effect in preventing bad smell and clarification of the wet paint booth circulating water.

  2. Description of the Related Art Conventionally, there is a spray coating method in which paint is sprayed on an object to be coated as a kind of coating method for automobiles, electrical products and the like. In the spray painting method, paint is sprayed in a wet painting booth in order to maintain the quality of the paint and preserve the work environment.

  This wet painting booth has a painting chamber for spraying paint on an object to be coated, a duct having a fan for sucking air in the painting chamber, and a contact portion for bringing the sucked air and the booth circulating water into contact with each other. And a pit capable of storing booth circulating water. In this wet painting booth, uncoated paint that has not been applied to the object to be coated is sucked into the duct together with air by the fan. At this time, the uncoated paint is collected in contact with the booth circulating water at the contact portion, and separated by settling or floating the uncoated paint. The uncoated paint thus separated is collected and discarded.

  However, a portion of the unpainted paint floats and circulates in the booth circulating water without being separated, and adheres to the inner surface of the piping and reduces the circulating water volume of the booth circulating water. Furthermore, the painting operation may even need to be stopped if the amount of circulating water is significantly reduced. In order to prevent such problems, a paint treatment agent is added to the booth circulating water in advance to detack the unpainted paint floating in the booth circulating water and facilitate solid-liquid separation. Yes.

Examples of such paint treating agents include, for oil-based paints, alkaline agents such as caustic soda, cationic polymers, inorganic flocculants, melamine-aldehyde resin acid colloids (see Patent Document 1), and the like. The alkaline agent saponifies the surface of the uncoated oil-based paint to make it non-tacky, thereby preventing the non-coated oil-based paint from adhering to the pipe. Further, the cationic polymer, the inorganic flocculant and the melamine-aldehyde resin acid colloid adhere to the surface of the uncoated paint and become non-tacky to facilitate solid-liquid separation.
For uncoated water-based paints, a paint treatment agent containing polyethyleneimine as a component (see Patent Document 2) or a paint treatment agent containing a cationic organic compound and an anionic organic compound (see Patent Document 3). Etc. are used. These paint treatment agents facilitate solid-liquid separation of uncoated water-based paints that are uniformly dispersed or dissolved in Booth circulating water.

  As described above, in the conventional booth circulating water treatment method, solid-liquid separation of uncoated paint is facilitated by selecting an appropriate paint treatment agent according to the type of uncoated paint in the booth circulating water. It can be carried out. However, in recent years, the number of companies promoting industrial waste reduction and recycling promotion as environmental targets has increased, and the frequency of replacement of booth circulating water has been reduced, and repeated use over a long period of time. It tends to increase and concentrate turbid components. Considering the environmental impact of organic solvents, the use of water-based paints as well as oil-based paints that have been widely used in the past has greatly increased. The operating system of the painting booth, such as a booth and a painting booth that uses a mixture of water-based paint and oil-based paint, has become complex and diverse, and along with that, paint components and solvent components that dissolve or disperse in the booth circulating water are also increasing Because of increasing complexity and increasing, new problems have arisen due to this situation.

  The first of such new problems is the worsening of bad odor, and the second is the increase in the concentration of turbid components. As the use of water-based paints increases, as mentioned above, the paint components and solvent components that dissolve or disperse in the booth circulating water are becoming more complex and increasing, so the COD of the booth circulating water increases dramatically. Therefore, it has a complicated and serious aspect that is completely different from the conventional bad odor mainly of organic solvent odor that uses oil-based paint. In addition, the concentration and increase of turbid components in the booth circulation water promote the generation of insect pests such as butterflies and chironomids, leading to deterioration of the working environment and an increase in painting defects. Furthermore, when the turbid component in water settles, the amount of industrial waste processing at the time of cleaning increases, and cleaning costs are required. In addition, booth circulating water having a high concentration of turbid components is liable to produce malodors and causes deterioration of the working environment and the surrounding environment.

  Conventionally, toluene, xylene, ethyl acetate and methyl isobutyl ketone, which are used in large quantities as organic solvents in oil-based paints, are mixed and dissolved in booth circulating water, resulting in organic solvent odor, aldehyde odor, carboxylic acid Odors were generated, resulting in a worsening work environment and causing complaints from the surrounding residents. As a countermeasure, a paint treatment agent containing hexahydro-1,3,5-tris (2-hydroxyethyl) -S-triazine as a bactericidal agent (see Patent Document 4) or a paint treatment containing a tetraalkylphosphonium salt. An agent (see Patent Document 5) has been proposed, and the use of ozone (see Patent Document 6) has been proposed.

  However, in order to deal with the significant increase in the use of water-based paints in recent years and the complexity and diversification of the operating system of painting booths, the effects of conventional measures against bad odor mainly for oil-based paints are not sufficient. In addition, no effective countermeasures have been obtained for the removal of high-concentration turbid components.

Japanese Patent Publication No. 6-2259 JP-A-61-74607 JP-A 63-42706 Japanese Patent Laid-Open No. 6-3281 JP 2007-238537 A JP-A-8-323255

  The present invention has been made in view of the above-mentioned conventional circumstances, and the recent significant increase in the use of water-based paints, the complexity of the operation mode of paint booths, It is an object to be solved to provide a wet coating booth treatment agent and a treatment method that can cope with a high concentration of turbid components.

  In order to solve the above-mentioned problems, the present inventors have intensively studied, and as a result, the specific α-chlorobenzaldoxime compound has an excellent effect of preventing the bad odor of the wet paint booth circulating water, and further wet. The paint booth has also been found to have the effect of removing turbid components from circulating water and clarifying, and this specific α-chlorobenzaldoxime compound is used in oil paints alone, water paints alone, water paints and oil paints. The present invention has been completed by confirming that the above-mentioned effects can be stably exhibited even in coating booths of different operation modes that are mixed and used.

  Since α-chlorobenzaldoxime compounds are generally used as water-based disinfectants, the present inventors have determined that specific α-chlorobenzaldoxime compounds used in the present invention can be used under the condition of using an oil-based paint alone. Although the odor prevention effect could be expected, a stable odor prevention effect was obtained even under the condition of using a water-based paint alone and under the condition of using a mixture of a water-based paint and an oil-based paint. It was impossible to predict the effect of clarifying by removing the quality component.

（ただし、式中、Ｒ_１は水素原子または塩素原子を示し、Ｒ_２は水素原子またはアセチル基を示す。） That is, the present invention relates to a wet paint booth circulating water treatment agent characterized by containing an α-chlorobenzaldoxime compound represented by the following general formula (1).

(In the formula, R ₁ represents a hydrogen atom or a chlorine atom, and R ₂ represents a hydrogen atom or an acetyl group.)

  The present invention provides a wet paint booth circulating water treatment agent in which the compound represented by the general formula (1) is α-chloro-p-chlorobenzaldoxime.

（ただし、式中、Ｒ_１は水素原子または塩素原子を示し、Ｒ_２は水素原子またはアセチル基を示す。） The present invention is regarding the represented α- chloro benzaldoxime compound of the following general formula (1), the wet paint spray booth circulating water treatment method characterized by adding to the wet paint spray booth circulating water.

(In the formula, R ₁ represents a hydrogen atom or a chlorine atom, and R ₂ represents a hydrogen atom or an acetyl group.)

  The present invention is characterized in that the α-chlorobenzaldoxime compound represented by the general formula (1) is added so that the concentration in the wet coating booth circulating water is 0.1 to 100 mg / L. A wet paint booth circulating water treatment method is provided.

  The present invention also provides a wet paint booth circulating water treatment method in which the α-chlorobenzaldoxime compound represented by the general formula (1) is α-chloro-p-chlorobenzaldoxime. .

  By applying the wet paint booth circulating water treatment agent and the treatment method of the present invention, it is possible to obtain excellent effects of preventing bad smell and clarifying of booth circulating water regardless of the type of paint used.

It is a schematic diagram of the wet coating booth for a test used for the Example and the comparative example.

  There are no particular restrictions on the type of wet coating booth to be treated by the wet coating booth circulating water treatment agent and processing method of the present invention, water curtain type, venturi type, no pump type and variations of these types, as well as these types It also includes a painting booth where various incidental facilities are connected to the painting booth.

  In the wet paint booth circulating water treatment agent and treatment method of the present invention, the oil-based paint to be treated is not particularly limited. For example, epoxy resin paint, polyester resin paint, urethane resin paint, alkyd resin paint, amino resin paint, Examples include vinyl resin paints, acrylic resin paints, phenol resin paints, cellulose derivative paints, and alcoholic paints. Also, the water-based paint to be treated is not particularly limited, and examples thereof include a water-based alkyd resin paint, a water-based polyester resin paint, a water-based acrylic resin paint, and a water-based polyurethane resin paint.

  There is no particular limitation on the usage form of the paint in the wet paint booth to be treated by the wet paint booth circulating water treatment agent and treatment method of the present invention, the oil paint alone use, the water paint alone use, and the water paint and oil paint The present invention can be applied to any use booth of mixed use.

  Specific α-chlorobenzaldoxime compounds used in the wet paint booth circulating water treatment agent and treatment method of the present invention include, for example, α-chlorobenzaldoxime, α-chloro-p-chlorobenzaldoxime, α- Examples include chloro-benzaldoxime acetate and α-chloro-p-chlorobenzaldoxime acetate. Among them, α-chloro-p-chlorobenzaldoxime is preferable in terms of the clarification effect.

The wet paint booth circulating water treatment agent of the present invention has a specific α-chlorobenzaldoxime compound, which is an active ingredient, which is hardly soluble in water. To form a dispersant prepared by dispersing in water. Hydrophilic solvents include alcohols such as methanol and ethanol, glycols such as ethylene glycol, propylene glycol, diethylene glycol and dipropylene glycol, methyl cellosolve, phenyl cellosolve, diethylene glycol monomethyl ether, dipropylene glycol monoethyl ether, and tripropylene glycol. Glycol ethers such as monomethyl ether, alcohols having up to 8 carbon atoms, methyl acetate, ethyl acetate, 3-methoxydibutyl acetate, 2-ethoxymethyl acetate, 2-ethoxyethyl acetate, esters such as propylene carbonate, dimethylformamide, etc. Of the amides.

  In the form of a dispersing agent, a specific α-chlorobenzaldoxime compound as an active ingredient is dispersed in water using a cationic surfactant, an anionic surfactant, a nonionic surfactant or an amphoteric surfactant. . Among these, nonionic surfactants are preferred, higher alcohol ethylene oxide adducts, alkylphenol ethylene oxide adducts, fatty acid ethylene oxide adducts, polyhydric alcohol fatty acid ester ethylene oxide adducts, higher alkylamine ethylene oxides. Examples include adducts, ethylene oxide adducts of fatty acid amides, fatty acid esters of glycerin, fatty acid esters of pentaerythritol, fatty acid esters of sorbitol and sorbitan, fatty acid esters of sucrose, alkyl ethers of polyhydric alcohols, alkylolamides, and the like.

  Although the addition place of the wet coating booth circulating water treatment agent of this invention in a wet coating booth is not specifically limited, What is necessary is just a location with which a processing agent is easy to be mixed in booth circulating water, and the front of a circulation pump etc. are preferable. The addition method is not particularly limited, but can be appropriately selected such as continuous addition with a metering pump or intermittent addition.

  The amount of the wet coating booth circulating water treatment agent of the present invention varies depending on the type of coating booth to be treated, the paint used, the operating conditions, etc., but usually a specific α-chlorobenzaldoxime is added to the booth circulating water. The concentration of the compound is 0.1 to 100 mg / L, preferably 1 to 20 mg / L. When the amount is less than 0.1 mg / L, sufficient malodor prevention and clarification effects may not be obtained. When the amount is more than 100 mg / L, the obtained effect is sufficient. In some cases, the effect corresponding to the increase cannot be obtained, which is not preferable from an economic viewpoint.

  The wet coating booth circulating water treatment agent of the present invention may contain other known components as long as the effects of the present invention are not impaired. Examples of other known components include viscosity modifiers, antifoaming agents, and bactericides that contribute to the stability of the preparation.

  The wet painting booth circulating water treatment method of the present invention is a wet painting booth circulating water treatment method characterized by adding a specific α-chlorobenzaldoxime compound to the wet painting booth circulating water, and the addition method is The coating booth circulating water treatment agent containing the specific α-chlorobenzaldoxime compound may be used, or the specific α-chlorobenzaldoxime compound may be added directly to the wet coating booth circulating water. Although it is good, considering the dispersibility of the α-chlorobenzaldoxime compound in the booth circulating water, it is preferable to use the coating booth circulating water treatment agent.

  The addition location, the addition method, and the addition concentration in the case of using the coating booth circulating water treatment agent are as described above, and the specific α-chlorobenzaldoxime compound is directly added to the wet coating booth circulating water. The same applies to the case.

  In the wet paint booth circulating water treatment method of the present invention, known paint treating agents such as paint detackifying agents, cationic coagulants, and flocculants, which have been conventionally used as treatment agents for wet paint booths, and known dissipators. A foaming agent, a disinfectant, etc. can be used together.

  Examples of the paint non-tackifier include sodium hydroxide, sodium silicate, sodium zincate, alumina sol, silica sol, sodium aluminate, polyaluminum chloride, aluminum sulfate, ferric chloride, polyferric sulfate, melamine- Formaldehyde condensate, phenol-formaldehyde condensate, bentonite, sepiolite, higher alcohol or derivative thereof, higher fatty acid or derivative thereof, polyethylene wax or derivative thereof, paraffin wax or derivative thereof, polystyrene or derivative thereof, polyvinyl alcohol or derivative thereof, diallyl Examples thereof include dimethylammonium chloride-acrylamide copolymer. Among them, alumina sol, sodium aluminate, polyaluminum chloride, aluminum sulfate, melamine-formaldehyde condensate, phenol-formaldehyde condensate, higher fatty acids or derivatives thereof, polyethylene wax or derivatives thereof supplement the non-adhesive effect and clarification effect. It is preferable in terms of effect.

  Examples of the cationic coagulant include (meth) acrylic acid ester (alcohol ester having 1 to 4 carbon atoms) / (meth) acrylaminoethyltrimethylammonium copolymer, (meth) acrylamide / (meth) acrylaminoethyltrimethylammonium Copolymer, (meth) acrylaminodialkyl (alkyl group having 1 to 4 carbon atoms) / (meth) acrylaminoethyltrimethylammonium copolymer, (meth) acrylaminoethyl such as poly (meth) acrylaminoethyltrimethylammonium Trimethylammonium copolymer; Dicyandiamide-based condensates such as dicyandiamide-formaldehyde condensate, dicyandiamide-diethylenetriamine condensate; dimethylamine-epichlorohydrin condensate, diethylamine-epichlorohi Dialkylamine-epihalohydrin condensates such as phosphorus condensate, dimethylamine-epichlorohydrin-ammonia condensate, diethylamine-epichlorohydrin-ammonia condensate; polydiallyldimethylammonium chloride, diallyldimethylammonium chloride-acrylamide copolymer, diallyldimethylammonium chloride- Sulfur dioxide copolymer, diallyldimethylammonium chloride- (meth) acrylamide copolymer, diallyldimethylammonium chloride- (meth) acrylic acid copolymer, diallyldimethylammonium chloride- (meth) acrylic acid- (meth) acrylamide copolymer Diallyldimethylammonium chloride copolymer such as a polymer; polyethyleneimine, polyallylamine, polyvinyl Polyalkyl amines such as emissions and the like.

  Among these, polyacrylaminoethyltrimethylammonium chloride, dicyandiamide-formaldehyde condensate, dicyandiamide-diethylenetriamine condensate, dimethylamine-epichlorohydrin condensate, dimethylamine-epichlorohydrin-ammonia condensate, diallyldimethylammonium chloride polymer, diallyldimethylammonium A chloride-acrylamide copolymer, diallyldimethylammonium chloride-sulfur dioxide copolymer, polyethyleneimine, and polyvinylamine are preferred because of their high cation strength.

  The molecular weight of the cationic coagulant is not particularly limited, but is preferably in the range of 2,000 to 500,000. This is because if the molecular weight is within this range, the setting effect of the aqueous paint is particularly excellent.

  The flocculant is a water-soluble anionic, cationic or nonionic polymer and has a molecular weight of 1,500,000 to 20,000,000, preferably 2,000,000 to 15,000,000. It is a polymer. The flocculant has an effect of further facilitating the recovery by cross-linking and coarsening the paint particles solidified and solidified by coagulation and non-adhesion with a paint non-tackifier and / or a cationic coagulant.

  Examples of the flocculant include polyacrylamide, acrylamide-acrylic acid copolymer, acrylamide-acrylaminoethyltrimethylammonium chloride copolymer, acrylamide-methacrylaminoethyltrimethylammonium chloride copolymer, and acrylamide- [2- (acryloyloxy). And ethyl] benzyldimethylammonium chloride / [2- (acryloyloxy) ethyl] trimethylammonium copolymer, acrylamide-vinyl sulfonic acid copolymer and salts thereof, polyvinyl imidazoline, and polyethylene oxide.

  Among these, polyacrylamide, acrylamide-acrylic acid copolymer, acrylamide-acrylaminoethyltrimethylammonium chloride copolymer, acrylamide-methacrylaminoethyltrimethylammonium chloride copolymer, acrylamide- [2- (acryloyloxy) ethyl] A benzyldimethylammonium chloride / [2- (acryloyloxy) ethyl] trimethylammonium copolymer is preferred.

  The paint detackifier and flocculant can be used in booths that use either oil paint alone, water paint alone, or mixed use of water paint and oil paint. Thus, the addition method and the addition amount can be selected as appropriate in combination with the kind of the drug. The cationic coagulant is mainly used in a booth in the form of a single use of an aqueous paint or a mixed use of an aqueous paint and an oil paint, and it is also preferable to control the addition amount of the cationic coagulant by the amount of charge in the booth circulating water. The amount of charge in the booth circulating water varies greatly depending on the amount of cationic coagulant added, and if the amount of charge in the booth circulating water is -200 to +200 μeq / L, the paint particles can be easily separated from the water and recovered. It becomes extremely easy.

  When the amount of cationic coagulant added is controlled by the amount of charge in Booth circulating water, it can be measured by methods such as colloid titration, particle charge measurement (PCD method), electrophoresis, etc., and these methods are known. The detailed description thereof is omitted.

  As the antifoaming agent and disinfectant used in the wet paint booth circulating water, general known antifoaming agents and disinfecting agents used in water systems such as process water and waste water in various industries can be applied.

  In the wet coating booth circulating water treatment method of the present invention, the paint treatment agent, antifoaming agent, disinfectant and the like are applied in the conventional manner regardless of the application of the specific α-chlorobenzaldoxime compound of the present invention. Can be used.

  Hereinafter, the present invention will be described in detail by way of examples embodying the present invention. However, the present invention is not limited to the following examples, and does not depart from the description of the scope of claims. Various modifications as long as those skilled in the art can easily conceive are also included in the present invention.

(Equipment used for testing)
In the examples and comparative examples, the test wet coating booth shown in FIG. 1 was used. This booth simulates a general large-scale wet painting booth, and includes a painting chamber 1, a circulating water pit 2, and a concentration collection tank 3. The paint 4 is sprayed in the painting chamber 1, and the uncoated paint is collected in contact with the booth circulating water 6 supplied to the painting chamber 1 at the contact portion 5 and flows down to the circulating water pit 2. In this test wet coating booth, there is no object to be coated, and all the sprayed paint becomes uncoated paint. The unpainted paint collected in the booth circulating water 6 at the contact portion 5 floats and separates in the form of sludge in the circulating water pit 2 and is sucked together with the booth circulating water by the concentrated recovery tank feed pump 7 to the concentrated recovery tank 3. Sent. In the concentration and recovery tank 3, the sludge of the uncoated paint is concentrated by the pressure floating action, and the concentrated sludge 8 is recovered and carried out of the system. On the other hand, the treated water 9 separated from the sludge in the concentration recovery tank 3 returns to the circulating water pit 2. The booth circulating water stored in the circulating water pit 2 is sent to the painting chamber as the booth circulating water 6 by the circulation pump 10. 11, 12, and 13 are the addition positions of the chemicals in Examples and Comparative Examples. In the addition position 11, the treatment agent and the cationic coagulant of the present invention are added, and in the addition position 12, the coating tackifier is added and added. At point 13, a flocculant is added. The test wet coating booth has 500L of water, the circulating water volume of the booth circulating water by the circulation pump 10 is 100L / min, and the water supply volume to the concentration recovery tank 3 by the concentration recovery tank feed pump 7 is 30L / min. All examples and comparative examples were tested under the conditions.

(Drugs used in Examples and Comparative Examples)
(A) Treatment agent of the present invention and conventionally known malodor control agent A-1: Agent prepared by dissolving 2 parts by weight of α-chloro-p-chlorobenzaldoxime in 98 parts by weight of diethylene glycol (treatment agent of the present invention )
A-2: Agent prepared by dissolving 2 parts by weight of α-chlorobenzaldoxime in 98 parts by weight of diethylene glycol (the treatment agent of the present invention)
A-3: Agent prepared by dissolving 2 parts by weight of α-chlorobenzaldoxime acetate in 98 parts by weight of diethylene glycol (treatment agent of the present invention)
A-4: Drug prepared by dissolving 2 parts by weight of hexahydro-1,3,5-tris (2-hydroxyethyl) -S-triazine and 5 parts by weight of sodium hydroxide in 93 parts by weight of pure water (known in the art) Odor control agent)
A-5: Drug prepared by dissolving 2 parts by weight of tri-n-butyl-n-hexadecylphosphonium chloride in 98 parts by weight of pure water (previously known malodor control agent)
(B) Paint detackifying agent B-1: Melamine-formaldehyde condensate [“Haktron S-830” manufactured by Hakuto Co., Ltd.]
B-2: poly aluminum chloride solution (active ingredient: 10 to 11% containing as _Al 2 _{O 3)}
B-3: Aluminum sulfate solution (active ingredient: contained 8% as Al ₂ O ₃ )
B-4: Alumina sol [“Hakutron S-600” manufactured by Hakuto Co., Ltd.]
B-5: Polyethylene wax emulsion [Maisei Chemical Co., Ltd. "Meikatex PEC-
270 ")
(C) Cationic coagulant C-1: Dimethylamine-epichlorohydrin condensate [“Wastex T-101-50” manufactured by Nagase & Co., Ltd.]
C-2: Polyethyleneimine [“Epomin P-1000” manufactured by Nippon Shokubai Co., Ltd.]
C-3: diallyldimethylammonium chloride-acrylamide copolymer [Senka Co., Ltd. “Senka Flock DC-7513”]
(D) Flocculant D-1: Acrylamide-acrylaminoethyltrimethylammonium chloride copolymer [“Aron Flock 3390” manufactured by MT Aquapolymer Co., Ltd.]
D-2: Acrylamide-acrylic acid copolymer ["Acofloc 2360" manufactured by MT Aquapolymer Co., Ltd.]

1. Odor control and clarification test of actual machine booth circulating water (Example 1)
循環 Used circulating water from a wet painting booth using a mixture of water-based paint and oil-based paint at an automobile factory. This paint booth uses water-based water-based topcoat paint for automobiles (manufactured by Nippon Paint Co., Ltd.) and oil-based paint solvent clear paint for automobiles (manufactured by Kansai Paint Co., Ltd.). It was not replaced for half a year and had a strong odor and a high concentration of turbidity. 500 L of this booth circulating water is put into the circulating water pit 2 of the test wet paint booth shown in FIG. 1, and the circulating pump 10 circulates the booth circulating water at 100 L / min, and the concentrated recovery tank feed pump 7 concentrates and collects the booth circulating water. Water is fed to the tank 3 at 30 L / min, and the turbidity in the circulating water is concentrated in the concentration and recovery tank 3 by the pressure floating action, and the concentrated sludge 8 is recovered and carried out of the system. To this system, A-1 was added from the addition site 11 as an active ingredient to the booth circulating water once a day so that it might become 10 mg / L as a processing agent of this invention. In this test, the paint was not sprayed, and no chemicals other than the treatment agent of the present invention were added. About the water | moisture content removed by the volatilization and scattering during a test, and sludge, fresh water was replenished so that the water level of the circulating water pit 2 might be maintained. After the test wet coating booth was continuously operated for 3 days, the booth circulating water was collected, turbidity was measured, sensory evaluation of odor was performed, and odor intensity was determined by a six-step odor intensity display method.

(Comparative Example 1)
In Comparative Example 1, the drug to be added is replaced with A-1, and A-4 is added once a day as an active ingredient from the addition site 11 so as to be 10 mg / L with respect to the booth circulating water. The test was performed in the same manner as in Example 1 except that.

(Comparative Example 2)
In Comparative Example 2, the drug to be added was replaced with A-1, and A-5 was added from the addition site 11 once a day so that the active ingredient was 10 mg / L with respect to the booth circulating water. The test was performed in the same manner as in Example 1 except that.

(Comparative Example 3)
In Comparative Example 3, the test was performed in the same manner as in Example 1 without adding the treatment agent of the present invention and without adding other chemicals. In other words, this is an example of no processing.

  Table 1 shows the turbidity measurement results and the odor intensity determination results of the booth circulating water after completion of the tests of Example 1 and Comparative Examples 1 to 3.

（＊）臭気強度の官能評価は表２に従った。

(*) Sensory evaluation of odor intensity was in accordance with Table 2.

  From the results shown in Table 1, the wet paint booth circulating water treatment agent containing the specific α-chlorobenzaldoxime compound of the present invention has an excellent malodor prevention effect as compared with a conventionally known malodor prevention agent. In particular, it has been revealed that a remarkable booth circulating water clarification effect that cannot be obtained with a conventionally known malodor control agent is exhibited.

2. Booth circulating water treatment test (1) (water paint and oil paint mixing conditions)
(Example 2)
500 L of fresh water is introduced into the circulating water pit 2 of the test wet coating booth shown in FIG. 1, the booth circulating water is circulated at 100 L / min by the circulation pump 10, and the concentration recovery tank feed pump 7 moves to the concentration recovery tank 3. Water is fed at a rate of 30 L / min, turbidity in the circulating water is concentrated in the concentration and recovery tank 3 by the pressurized floating action, and the concentrated sludge 8 is recovered and carried out of the system. While adding the additive agent shown in Example 2 of Table 3 to this system in the addition amount shown in Example 2 of Table 3, each of the aqueous paint and the oil paint is directed toward the booth circulating water in the coating chamber 1. Spraying was continued for 5 hours a day at 5 g / min. As the water-based paint, a water-based top coat for automobiles (manufactured by Nippon Paint Co., Ltd.) was used, and as the oil-based paint, a solvent clear paint for automobiles (manufactured by Nippon Paint Co., Ltd.) was used. Here, the additive A-1 which is the treatment agent of the present invention was added from the addition site 11 once a day so as to be 10 mg / L as an active ingredient with respect to the booth circulating water. Moreover, 1 weight% of additive chemical | medical agents B-1 as an active ingredient was added from the addition location 12 during spraying with respect to the total paint (= water-based paint + oil-based paint) weight sprayed in the coating booth. The additive C-1 was added at 1 part by weight as an active ingredient from the addition site 11 during spraying with respect to the weight of the aqueous paint sprayed at the coating booth. The additive drug D-1 was added from the addition site 13 during spraying by 0.3% by weight as an active ingredient based on the total weight of the paint (= water-based paint + oil-based paint) sprayed in the painting booth. While spraying the paint, the charge of the booth circulating water was measured, and the cationic coagulant was added so that the charge was -200 to +200 (μeq / L-booth circulating water). In addition, the amount of the cationic coagulant added in the booth circulating water within a predetermined charge range is confirmed in advance by a preliminary test, and the amount of the cationic coagulant shown in Table 3 is determined. The charge of the booth circulating water was measured by colloid titration. About the water | moisture content removed by the volatilization and scattering during a test, and sludge, fresh water was replenished so that the water level of the circulating water pit 2 might be maintained. After the test wet coating booth was continuously operated for 14 days, the booth circulating water was collected, the turbidity was measured, the sensory evaluation of the odor was performed, and the odor intensity was determined by a six-step odor intensity display method.

(Examples 3 to 13, Comparative Examples 4 to 6)
In Examples 3 to 13 and Comparative Examples 4 to 6, Examples were added except that the additive agents shown in each Example and each Comparative Example in Table 3 were added in the addition amounts shown in each Example and each Comparative Example in Table 3. The treatment test (1) of the booth circulating water was conducted in the same manner as 2 and the test results were obtained.

(Comparative Example 7)
In Comparative Example 7, the treatment test (1) of the booth circulating water was performed without adding the chemical, and the test result was obtained. In other words, this is an example of no processing.

  Table 3 shows the turbidity measurement results and the odor intensity determination results of the booth circulating water after the tests of Examples 2 to 13 and Comparative Examples 4 to 7, and the average value of the charge of the booth circulating water during the test.

（１）添加量：添加薬剤Ａは、ｍｇ／Ｌ対循環水保有水量、薬剤ＢとＤは重量％対総塗料重量、薬剤Ｃは重量％対水性塗料重量を示す。
（２）臭気強度の官能評価は表２に従った。

(1) Addition amount: Addition drug A indicates mg / L vs. amount of water retained in circulating water, drugs B and D indicate% by weight with respect to total paint weight, and drug C indicates% by weight with respect to water-based paint weight.
(2) Sensory evaluation of odor intensity was in accordance with Table 2.

As shown in Table 3, the charge of the booth circulating water is −200 to +200 (μeq / L− by adding the treatment agent of the present invention and / or the paint tackifier and / or the cationic coagulant and / or the flocculant. In Examples 2 to 13 in which the addition amount of the cationic coagulant was adjusted so as to be a booth circulating water), excellent effects were exhibited with a turbidity of 110 degrees or less and an odor intensity of 2 or less.
On the other hand, in Comparative Example 4, the treatment agent of the present invention was not added, and the paint detackifying agent, the cationic coagulant and the flocculant were added to adjust the booth circulating water charge to an appropriate range. The turbidity is as high as 285 degrees, and the odor intensity is as high as 3 to 4, so that the clarity of the booth circulating water is not sufficient, and it can be seen that it is odorous. In Comparative Example 5 or Comparative Example 6, the charge of Booth circulating water is adjusted to an appropriate range by adding a conventionally known malodor prevention agent, a coating tackifier, a cationic coagulant and a flocculant. However, the turbidity is as high as 282 to 310 degrees, the odor intensity is as high as 3 to 4, and the clearness of the booth circulating water is not sufficient, and it can be seen that it is odorous.
From the result comparison of the above Examples 2-13 and Comparative Examples 4-7, the outstanding clarification effect with respect to the wet coating booth circulating water and the malodor prevention effect of this invention were shown clearly.

3. Booth circulating water treatment test (2) (oil paint alone condition)
(Examples 14-18, Comparative Examples 8-10)
In Examples 14 to 18 and Comparative Examples 8 to 10, the paint to be sprayed and the spray amount thereof were changed from “5 g / min each for water-based paint and oil-based paint” to “10 g / min for oil-based paint”, and The test was performed in the same manner as in Example 2 except that the additive agents shown in each Example 4 and each Comparative Example were added in the addition amounts shown in each Example and each Comparative Example in Table 4, and the booth circulating water was treated. The test result of test (2) was obtained. The method of determining the addition amount of the cationic coagulant shown in Table 4 was also in accordance with Example 2. As the oil-based paint, an automotive solvent intermediate coating (manufactured by Kansai Paint Co., Ltd.) was used.

(Comparative Example 11)
In Comparative Example 11, the treatment test (2) of the booth circulating water was performed without adding the chemical, and the test result was obtained. In other words, this is an example of no processing.

  Table 4 shows the turbidity measurement results and the odor intensity determination results of the booth circulating water after the tests of Examples 14 to 18 and Comparative Examples 8 to 11, and the average value of the charge of the booth circulating water during the test.

（１）添加量：添加薬剤Ａは、ｍｇ／Ｌ対循環水保有水量、薬剤ＢとＤは重量％対総塗料重量、薬剤Ｃは重量％対水性塗料重量を示す。
（２）臭気強度の官能評価は表２に従った。

(1) Addition amount: Addition drug A indicates mg / L vs. amount of water retained in circulating water, drugs B and D indicate% by weight with respect to total paint weight, and drug C indicates% by weight with respect to water-based paint weight.
(2) Sensory evaluation of odor intensity was in accordance with Table 2.

  As shown in Table 4, in Examples 14 to 18 of the present invention, excellent effects with turbidity of 60 degrees or less and odor intensity of 2 or less were exhibited. On the other hand, in Comparative Examples 8 to 10 in which the treatment agent of the present invention is not added, the turbidity is 180 degrees or more, the odor intensity is 3, the clarity of the booth circulating water is not sufficient, and it can be seen that the odor is present. From the result comparison of the above Examples 14-18 and Comparative Examples 8-11, the outstanding clarification effect and malodor prevention effect with respect to the wet painting booth circulating water of this invention were shown clearly.

4). Booth circulating water treatment test (3) (water-based paint single condition)
(Examples 19-22, Comparative Examples 12-14)
In Examples 19 to 22 and Comparative Examples 12 to 14, the paint to be sprayed and the spray amount thereof were changed from “5 g / min each for water-based paint and oil-based paint” to “10 g / min for water-based paint”, and The test was performed in the same manner as in Example 2 except that the additive chemicals shown in each Example 5 and each Comparative Example were added in the addition amounts shown in each Example and each Comparative Example in Table 5, and the booth circulating water was treated. The test result of test (3) was obtained. The method for determining the addition amount of the cationic coagulant shown in Table 5 was also in accordance with Example 2. As the water-based paint, a water-based top coat for automobiles (manufactured by Kansai Paint Co., Ltd.) was used.

(Comparative Example 15)
In Comparative Example 15, the booth circulating water treatment test (3) was performed without adding any chemicals, and the test results were obtained. In other words, this is an example of no processing.

  Table 5 shows the turbidity measurement results and the odor intensity determination results of the booth circulating water after the tests of Examples 19 to 22 and Comparative Examples 12 to 15, and the average value of the charge of the booth circulating water during the test.

（１）添加量：添加薬剤Ａは、ｍｇ／Ｌ対循環水保有水量、薬剤ＢとＤは重量％対総塗料重量、薬剤Ｃは重量％対水性塗料重量を示す。
（２）臭気強度の官能評価は表２に従った。

(1) Addition amount: Addition drug A indicates mg / L vs. amount of water retained in circulating water, drugs B and D indicate% by weight with respect to total paint weight, and drug C indicates% by weight with respect to water-based paint weight.
(2) Sensory evaluation of odor intensity was in accordance with Table 2.

  As shown in Table 5, in Examples 19 to 22 of the present invention, excellent effects with turbidity of 40 degrees or less and odor intensity of 1 or less were shown. On the other hand, in Comparative Examples 12 to 14 in which the treatment agent of the present invention is not added, the turbidity is 230 degrees or more, the odor intensity is 3 to 4, the clarity of the booth circulating water is not sufficient, and it can be seen that it is odorous. From the result comparison of the above Examples 19-22 and Comparative Examples 12-15, the outstanding clarification effect and the malodor prevention effect with respect to the wet coating booth circulating water of this invention were shown clearly.

  The present invention can be applied to a wet painting booth where the bad smell and turbidity problem of the circulating water of the booth is particularly serious due to the use of the water-based paint, and can obtain an excellent bad smell prevention effect and clarification effect.

1. Painting room Circulating water pit 3. Concentration collection tank 4. Paint Contact part 6. Booth circulating water 7. 7. Concentration recovery tank feed pump 8. Concentrated sludge Treated water 10. Circulation pump 11.12.13. Drug addition location

Claims (4)

A wet paint booth circulating water treatment agent comprising an α-chlorobenzaldoxime compound represented by the following general formula (1).

(In the formula, R ₁ represents a hydrogen atom or a chlorine atom, and R ₂ represents a hydrogen atom or an acetyl group.)   The wet paint booth circulating water treatment agent according to claim 1, wherein the compound represented by the general formula (1) is α-chloro-p-chlorobenzaldoxime. The α-chlorobenzaldoxime compound represented by the following general formula (1) is added to the wet paint booth circulating water so that the concentration in the wet paint booth circulating water is 0.1 to 100 mg / L. Wet paint booth circulating water treatment method.

(In the formula, R ₁ represents a hydrogen atom or a chlorine atom, and R ₂ represents a hydrogen atom or an acetyl group.) The wet paint booth circulating water treatment method according to claim 3 , wherein the α-chlorobenzaldoxime compound represented by the general formula (1) is α-chloro-p-chlorobenzaldoxime.

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