JP2010155246A - Method for forming photoluminescent coating film and coated material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for forming a photoluminescent coating film that gives feelings of luminosity of high-degree appearance using a water based paint together with a first base coating and a second base coating without preheating after the first base coating is performed. <P>SOLUTION: The method for forming a photoluminescent coating film is such that a first base coating film is formed by applying a water first-base photoluminescent coating onto a coated film formation over each predetermined coating zone, subsequently, a second base coating film is formed by applying a water second-base photoluminescent coating onto the first base coating film, a clear coating film is formed by applying a clear coating onto the second base coating film, and the uncured coating film obtained above is heat cured at once with the conditions (A): the solid content of coating in the water first base photoluminescent coating is 10 to 45 mass% and the solid content of coating in the aqueous second-base photo luminescent coating is 10 to 40 mass%, and (B): the solid content ratio of coating of the water first base photoluminescent coating and the water second base photoluminescent coating satisfies (1.1/1) to (4/1). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a glitter coating film forming method and a coated product.

  Conventionally, paints containing aluminum powder or mica powder have been used as glitter paints for forming metallic coatings having metallic gloss.

  As a method of forming a glittering coating film using these glittering paints, Japanese Patent Application Laid-Open No. 2002-35688 forms a metallic coating film having excellent orientation, denseness, flip-flop property, and glittering feeling. With respect to a method for forming a coating film, a thermosetting base paint (A) containing a hydrophilic organic solvent and water is applied to an object to be coated, the applied coating film is not cured, and the solid content is 70. A method for forming a multi-layer coating film is described in which a coating material adjusted to at least mass% is coated with a hydrophilic organic solvent-containing metallic paint (B) and, if necessary, a clear paint (C). (See Patent Document 1).

  However, in the method according to Patent Document 1, since the hydrophilic organic solvent-containing metallic paint (B) corresponding to the second base paint does not contain water as a solvent and uses an organic solvent as a whole solvent, the environment based on VOC (volatile organic compound) is used. Measures are required from the viewpoint of impact on the surface. Furthermore, the method according to the above-mentioned patent document 1 applies the base coating in order to apply the thermosetting base coating (A), not to cure the coating film, and to adjust the solid content to 70% by mass or more. A preheating process is required in the zone, which complicates the line design.

JP 2002-35688 A

  Accordingly, an object of the present invention is to provide a method of forming a glittering coating film that gives a high-quality glitter feeling without preheating after applying the first base paint using both the first base paint and the second base paint. It is to provide a painted product.

  As a result of intensive studies in view of the above problems, the present inventors have arrived at the present invention.

  1. The coating film forming material is subjected to the following steps (1) to (4) in order, and a glittering coating film forming method that satisfies the following conditions (A) and (B), step (1): the base coating zone A step of applying a water-based first base glitter paint in one stage to form a first base coating film, step (2): the first step obtained in the step (1) in the second stage of the base coating zone. A step of applying a water-based second base glitter coating on the base coating film to form a second base coating film, step (3): the second base coating film obtained in the step (2) in the clear coating zone Step of applying clear paint on top to form a clear coating film, and Step (4): heating all uncured coating films obtained by the above steps (1), (2) and (3) at a time Step of curing; condition (A): the above-mentioned aqueous first base glitter The paint solid content in the paint is 10 to 45 mass%, the paint solid content in the aqueous second base glitter paint is 10 to 40 mass%, and the condition (B): the aqueous first base glitter paint and the aqueous paint. The paint solid content ratio with the 2-base glitter paint is (1.1 / 1) to (4/1).

  2. A glossy coating film forming method that satisfies the following conditions (A) and (B) through the following steps (1), (2), and (5) in order on the coating film-formed product, step (1): base coating Step (2) of applying a water-based first base glitter paint in the first stage of the zone to form a first base coating film: obtained in the step (1) in the second stage of the base coating zone. A step of applying a water-based second base glitter coating on the first base coating film to form a second base coating film, and step (5): all the steps obtained by the above steps (1) and (2) Step of heat-curing an uncured coating film at once; Condition (A): 10 to 45% by mass of paint solid content in the aqueous first base glitter paint, and solid paint in the aqueous second base glitter paint 10-40% by weight, condition (B): the aqueous first base light Paint solids ratio of sex paint and the second aqueous base bright paint, (1.1 / 1) - (4/1).

  3. Furthermore, the above-mentioned glitter coating film forming method that satisfies the following condition (C), Condition (C): The dry film thickness ratio between the first base coating film and the second base coating film is (1.5 / 1). ) To (5/1).

  4). Further, the above-mentioned glitter coating film forming method that satisfies the following conditions (D) and (E), condition (D): the PWC of the glitter pigment in the aqueous first base glitter paint is 1 to 30%, the aqueous The PWC of the glitter pigment in the second base glitter paint is 5 to 40%. Condition (E): the PWC of the glitter pigment contained in the aqueous first base glitter paint and the aqueous second base glitter paint. The ratio is (1/4) to (1 / 1.1).

  5. The method for forming a glittering coating film according to the invention, wherein the aqueous second base glittering paint contains 0.1 to 5 parts by mass of a fluorine-based or silicone-based additive with respect to 100 parts by mass of the vehicle solid part.

  6). Painted material painted by the above-mentioned glitter coating film forming method.

  In the first glittering coating film forming method of the present invention, the water-based first base coating material is applied to the coating film forming object in the step (1): the first stage of the base coating zone, and the first base coating film is applied. Step of forming, step (2): In the second stage of the base coating zone, an aqueous second base coating is applied on the first base coating obtained in step (1) to form a second base coating Step (3): In the clear coating zone, a step of applying a clear paint on the second base coating film obtained in the step (2) to form a clear coating film, and a step (4): A step of sequentially heating and curing all uncured coating films obtained by the above steps (1), (2) and (3) at the same time, wherein the condition (A): the aqueous first base paint The solid content of the paint is 10 to 45% by mass, The paint solid content in the paint is 10 to 40% by mass, condition (B): the paint solid content ratio of the aqueous first base paint and the aqueous second base paint is (1.1 / 1) to (4 / 1); the second glittering coating film forming method further comprises applying the water-based first base coating material to the coating film forming object in the step (1): the first stage of the base coating zone. Step of coating and forming the first base coating film, step (2): In the second stage of the base coating zone, the aqueous second base coating material is coated on the first base coating film obtained in the above step (1). A step of forming a second base coating film, and a step (5): a step of heating and curing all uncured coating films obtained by the above steps (1) and (2) at a time. And condition (A): the solid content of the aqueous first base paint 10 to 45% by mass, the solid content of the aqueous second base paint is 10 to 40% by mass, and the condition (B): the solid content ratio of the aqueous first base paint and the aqueous second base paint is ( 1.1 / 1) to (4/1); the particle appearance is very small, and aluminum flake pigments having metallic luster have a metallic appearance without uneven brightness and interference. With a mica pigment having a property, it is possible to obtain a glittering coating film exhibiting a very high flip-flop property.

  In addition, since the multilayer coating film obtained by the present invention exhibits the above-mentioned glittering feeling, it is preferably used in fields that require glittering properties such as automobile outer panels such as automobiles and motorcycles, automobile parts (wheels, bumpers, etc.). .

  Hereinafter, the configuration of the present invention will be described in detail.

  In the first glittering coating film forming method of the present invention, a water-based first base glittering paint is applied to the coating film-formation object in the first stage of the step (1): base coating zone, and the first base coating is performed. Step for forming a film, step (2): In the second stage of the base coating zone, the second base glittering paint is applied on the first base coating film obtained in the step (1), and the second base Step of forming a coating film, step (3): In the clear coating zone, a step of coating a clear coating on the second base coating film obtained in the above step (2) to form a clear coating film, and a step (4): a step of heating and curing all uncured coating films obtained by the above steps (1), (2) and (3) at a time; 10 to 45 mass of paint solid content in the first base glitter paint The solid content of the paint in the aqueous second base glitter paint is 10 to 40% by mass. Condition (B): The paint solid content ratio of the aqueous first base glitter paint and the aqueous second base glitter paint is , (1.1 / 1) to (4/1);

  In the second glittering coating film forming method of the present invention, the water-based first base glittering paint is applied to the coating film-formation object in the step (1): the first stage of the base coating zone. Step of forming a base coating film, step (2): In the second stage of the base coating zone, an aqueous second base glitter paint is applied on the first base coating film obtained in the above step (1), A step of forming a base coating film, step (5): a step of heating and curing all uncured coating films obtained by the above steps (1) and (2) at a time; (A): 10 to 45% by mass of paint solid content in the aqueous first base glitter paint, 10 to 40% by mass of paint solid content in the aqueous second base glitter paint, Condition (B): above Coating of water-based first base glitter paint and water-based second base glitter paint Solids ratio is (1.1 / 1) - (4/1); formed to meet.

[Coating film formation]
The substrate constituting the coating film forming material used in the method for forming the glittering coating film of the present invention is not limited, and metals such as iron, aluminum, copper or alloys thereof; glass, cement, concrete Inorganic materials such as polyethylene resin, polypropylene resin, ethylene-vinyl acetate copolymer resin, polyamide resin, acrylic resin, vinylidene chloride resin, polycarbonate resin, polyurethane resin, epoxy resin, and various plastic materials such as FRP Natural or synthetic materials such as wood and fiber materials (paper, cloth, etc.);

  In the case of the automobile body and parts of the conductive substrate, the coating film formation in the glittering coating film forming method of the present invention is pre-coating by chemical conversion treatment, electrodeposition coating, etc., or undercoating and intermediate coating May be applied. Moreover, when the said coating-film formation thing is a motor vehicle body and components of a nonelectroconductive base material, after performing a chemical conversion process and a conductive process as needed, you may give a primer coating.

  The undercoat film formed by the above undercoat is formed to impart adhesion to the substrate, concealment of the substrate surface, anticorrosion and rust prevention, and after applying the undercoat It can be obtained by baking and curing. The film thickness of the said undercoat coating film is 8-30 micrometers, for example. The undercoat paint is not particularly limited, and examples thereof include a cationic electrodeposition paint and an anion electrodeposition paint. These are electrodeposited and then baked and cured according to the type of paint used.

  In addition, the intermediate coating film formed by the intermediate coating is formed to provide adhesion and concealment with the substrate surface and the undercoat coating film, and further to provide chipping resistance. It is formed on the undercoat coating film and can be obtained by applying an intermediate coating. The film thickness of the intermediate coating film is, for example, 10 to 50 μm. Examples of the intermediate coating material include those containing a hydroxyl group-containing polyester resin and / or a hydroxyl group-containing acrylic resin, a melamine resin, and / or a blocked polyisocyanate. Depending on the form of the paint used, these are dried or cured at room temperature or after baking.

  The base coating zone in the glittering coating film forming method of the present invention refers to the coating film on the lower layer side when forming the top coating film with a multilayer coating film, and this base coating film is formed. This is the paint area.

  In addition, the clear coating zone in the glittering coating film forming method of the present invention refers to an upper coating film when forming a top coating film with a multilayer coating film, which is called a clear top coating film. The painting area for forming a coating film.

  The first stage of the base coating zone in the glittering coating film forming method of the present invention refers to the first coating described above when the base coating film is continuously formed in the same coating zone. The stage refers to subsequent coating in the case of continuous formation. In the present invention, the point is to use different specific paints in the first stage and the second stage.

[Step (1)]
In step (1) of the glitter coating film forming method of the present invention, a water-based first base glitter paint (hereinafter also referred to as “water-based first base paint”) is applied in the first stage of the base paint zone. And forming the first base coating film.

  The water-based first base paint used for coating in the first stage of the base paint zone includes a water-based resin used as a film-forming resin constituting the vehicle. This aqueous resin can be made aqueous by adjusting its acid value and neutralizing the carboxyl group with a basic substance (for example, 50% or more). In the present invention, the aqueous resin includes a water-soluble resin, a water-dispersible resin, and an emulsion resin. Examples of basic substances used here include ammonia, methylamine, ethylamine, dimethylamine, diethylamine, trimethylamine, triethylamine, dimethylethanolamine, diethanolamine, and triethanolamine. Among these, diethanolamine, dimethylethanolamine, and triethanolamine are included. Ethanolamine and the like are preferred. As the solvent, water is the main component, but an organic solvent can be used in combination.

  As the coating film-forming resin constituting the vehicle, an acrylic resin and a polyester resin are preferably used, and an amino resin and / or a block polyisocyanate or a polycarbodiimide compound can be used as a crosslinking agent. When used as a base coating film, an acrylic resin is more preferable as the coating film forming resin.

  Examples of the acrylic resin include a copolymer of an acrylic monomer and another ethylenically unsaturated monomer. Acrylic monomers that can be used for the copolymerization include methyl, ethyl, propyl, n-butyl, i-butyl, t-butyl, 2-ethylhexyl, lauryl, phenyl, benzyl, 2-hydroxy of acrylic acid or methacrylic acid. Esterified products such as ethyl and 2-hydroxypropyl, amide groups such as acrylamide, methacrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, N, N-dibutylacrylamide, N, N-dibutylmethacrylamide Examples include acrylic monomers, ring-opening adducts of caprolactone of acrylic acid or 2-hydroxyethyl methacrylate, and (meth) acrylic acid esters of polyhydric alcohols. Examples of the other ethylenically unsaturated monomers copolymerizable with these include styrene, α-methylstyrene, itaconic acid, maleic acid, and vinyl acetate.

  Examples of the polyester resin include an oil-free polyester resin obtained by condensing a polyhydric alcohol component and a polybasic acid component, or castor oil, dehydrated castor oil, tung oil, safflower in addition to the polyhydric alcohol component and the polybasic acid component. Oil, soybean oil, linseed oil, tall oil, coconut oil, etc., and oil components that are one or a mixture of two or more of these fatty acids are added to the acid component and alcohol component to react the three And an oil-modified polyester resin obtained by the treatment.

  As the crosslinking agent, an amino resin and / or a block polyisocyanate or a polycarbodiimide compound is used, preferably an amino resin, specifically, di-, tri-, tetra-, penta-, hexa-methylol melamine. And alkyl etherified products thereof (alkyl is methyl, ethyl, propyl, isopropyl, butyl, isobutyl, etc.), urea-formaldehyde condensates, urea-melamine cocondensates, and the like. Of the above, melamine resin is more preferable.

  Blocked polyisocyanate is a polyisocyanate blocked with a blocking agent, and the block is removed at an elevated temperature. Examples of polyisocyanates include aliphatic diisocyanates such as trimethylene diisocyanate, hexamethylene diisocyanate and propylene diisocyanate; aromatic diisocyanates such as phenylene diisocyanate and naphthalene diisocyanate; aliphatic-aromatic isocyanates such as toluene diisocyanate and tolylene diisocyanate; Or more polyisocyanates such as triphenylmethane triisocyanate, tolylene diisocyanate dimer or trimer, and the like. Examples of blocking agents include alcohols such as methyl alcohol, ethyl alcohol; tertiary amines such as diethanolamine; lactams such as caprolactam; oximes such as methyl ethyl ketoxime.

  The polycarbodiimide compound is a compound having at least two carbodiimide groups (—N═C═N—) in the molecule. Specifically, poly (4,4′-diphenylmethanecarbodiimide), poly (3,3′-dimethyl-4,4′-biphenylmethanecarbodiimide), poly (tolylcarbodiimide), poly (P-phenylenecarbodiimide), poly (M-phenylene carbodiimide), poly (3,3'-dimethyl-4,4'-diphenylmethane carbodiimide), poly (naphthylene carbodiimide), poly (1,6-hexamethylene carbodiimide), poly (4,4'- Methylenebiscyclohexylcarbodiimide), poly (1,4-tetramethylenecarbodiimide), poly (1,3-cyclohexylenecarbodiimide), poly (1,4-cyclohexylenecarbodiimide), poly (1,3-diisopropylphenylenecarbodiimide), Poly (1-methyl- , 5-diisopropyl phenylene carbodiimide), poly (1,3,5-triethyl phenylene carbodiimide), poly (triisopropyl phenylene carbodiimide) and the like.

  The ratios of the resin for forming a coating film and the crosslinking agent in the vehicle of the first aqueous base paint are 90 to 50% by mass for the resin for forming the coating film and 10 to 50% by mass for the crosslinking agent. The film-forming resin is 85 to 60% by mass, and the crosslinking agent is 15 to 40% by mass. When the crosslinking agent is less than 10% by mass (when the coating film forming resin exceeds 90% by mass), crosslinking in the coating film is not sufficient. On the other hand, if the crosslinking agent exceeds 50% by mass (if the coating film forming resin is less than 50% by mass), the storage stability of the coating composition decreases and the curing rate increases, resulting in poor coating appearance.

  The aqueous first base paint contains a luster pigment, and if necessary, a color pigment or an extender pigment can be used. The bright pigments include aluminum flake pigments, metal oxide-coated alumina flake pigments, metal oxide-coated silica flake pigments, graphite pigments, interference mica pigments, colored mica pigments, metal titanium flake pigments, stainless steel flake pigments, plate oxidation Preference is given to at least one pigment selected from the group consisting of iron pigments, metal-plated glass flake pigments, metal oxide-coated plated glass flake pigments, hologram pigments and flake pigments composed of cholesteric liquid crystal polymers.

  In addition, as the above-mentioned colored pigments, azo lake pigments, insoluble azo pigments, condensed azo pigments, phthalocyanine pigments, indigo pigments, perinone pigments, perylene pigments, phthalone pigments, dioxazine pigments, quinacridone pigments as organic pigments Pigments, isoindolinone pigments, benzimidazolone pigments, diketopyrrolopyrrole pigments, metal complex pigments and the like, and inorganic irons include yellow iron oxide, bengara, carbon black, titanium dioxide, etc. Can be mentioned. Examples of the extender pigment include talc, calcium carbonate, precipitated barium sulfate, and silica.

  The aqueous first base paint is provided in a form in which the constituent components are usually dissolved or dispersed in water (deionized water) as a solvent. What substituted some water with the hydrophilic organic solvent is also contained. In the mixed system of water and organic solvent, the water content in the solvent is 51 to 100% by mass and the organic solvent content is 0 to 49% by mass. Including many.

  Examples of the organic solvent include those usually used in the paint field. For example, hydrocarbons such as toluene and xylene, ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate, butyl acetate, cellosolve acetate and butyl cellosolve, and alcohols can be exemplified. It is a solvent.

  In particular, among these solvents, alcoholic hydrophilic organic solvents such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, secondary butyl alcohol, tertiary butyl alcohol, ethylene glycol, 1,2-propylene glycol, 1 , 3-butylene glycol, 2,3-butylene glycol, hexylene glycol, 2,5-hexanediol, dipropylene glycol and the like.

  In addition to the above components, the first aqueous base paint includes an anti-settling agent, a curing catalyst, an ultraviolet absorber, an antioxidant, a leveling agent, a surface conditioner such as silicone and organic polymer, an anti-sagging agent, and a thickening agent. Additives such as antifoaming agents, lubricants, and crosslinkable polymer particles (microgel) can be added as appropriate.

[Step (2)]
Next, in the glitter coating film forming method of the present invention, in the step (2), in the second stage of the base coating zone, the aqueous second base glitter paint is applied on the first base coating film obtained in the above step (1). (Hereinafter, also referred to as “water-based second base paint”) is a step of forming a second base coating film.

  As the water-based second base paint used for coating in the second stage of the base paint zone, the vehicles, pigments, solvents and additives exemplified in the description of the water-based first base paint can be used.

  In the water-based second base paint, 0.1 to 5 parts by mass of a fluorine-based or silicone-based additive with respect to 100 parts by mass of the vehicle solid part is water-based due to a decrease in surface tension of the water-based second base paint. It is preferable from the viewpoint of improving wettability with respect to the first base coating film.

  Examples of the fluorine-based additive include fluorinated alkyl carboxylates, fluorinated alkyl alkoxylates, and fluorinated alkyl esters.

  Examples of the silicone-based additive include polyether-modified polymethylalkylsiloxane, polyether-modified polydimethylsiloxane, polyester-modified polymethylalkylsiloxane, silicone-modified polyacryl, and aralkyl-modified polymethylalkylsiloxane.

  If the fluorine-based or silicone-based additive is less than 0.1 parts by mass with respect to 100 parts by mass of the vehicle solid part, the surface tension may not be sufficiently lowered, and if it exceeds 5 parts by mass, the coating film performance decreases. There is a fear. More preferably, it is 0.2-2 mass parts.

[(A): Paint solid content of water-based first base paint and water-based second base paint]
In the method for forming a glittering coating film of the present invention, (A): the solid content of the aqueous first base paint is 10 to 45% by mass, and the solid content of the aqueous second base paint is 10 to 40% by mass. is there. If the solid content of the aqueous first base paint is less than 10% by mass, the amount of paint necessary to obtain the desired coating film thickness increases, so that the coating efficiency deteriorates. Appearance deteriorates. Preferably, it is 15-40 mass%. In addition, when the solid content of the aqueous second base paint is less than 10% by mass, the use amount of the paint necessary for obtaining a desired coating film thickness increases, so that the coating efficiency deteriorates and exceeds 40% by mass. And the orientation of the glitter pigment decreases. Preferably, it is 11-30 mass%. Here, the paint solid content is a paint solid content at the time of application, and refers to a heating residue after heating the paint to remove volatile components. The heating residue in the present invention is determined from the mass ratio between before and after heating when the paint is heated at 105 ° C. for 3 hours.

[(B): Paint solid content ratio of water-based first base paint and water-based second base paint]
In the glittering coating film forming method of the present invention, (B): the paint solid content ratio of the water-based first base paint and the water-based second base paint is (1.1 / 1) to (4/1). It is. That is, the solid content of the aqueous first base paint is always greater than the solid content of the aqueous second base paint. When the paint solid content ratio is out of the above range, the orientation of the glitter pigment is lowered. Preferably, it is (1.3 / 1) to (2.5 / 1).

[(C): Dry film thickness ratio of aqueous first base coating film and aqueous second base coating film]
In the glittering coating film forming method of the present invention, (C): the dry film thickness ratio between the first base coating film and the second base coating film is (1.5 / 1) to (5/1). It is preferable that That is, the dry film thickness of the aqueous first base coating film is always thicker than the dry film thickness of the aqueous second base coating film. When the dry film thickness ratio between the first base coating film and the second base coating film is less than 1.5 / 1, the orientation of the glitter pigment may be lowered. May occur. More preferably, it is (1.5 / 1) to (3/1).

  The dry film thickness ratio between the aqueous first base coating film and the aqueous second base coating film is as described above, and the dry first film thickness is preferably 5 to 15 μm for each dry film thickness. The dry film thickness of the aqueous second base coating film is preferably 2 to 8 μm.

[(D): PWC of luster pigment contained in water-based first base paint and water-based second base paint]
In the method for forming a glittering coating film according to the present invention, (D): the PWC of the glittering pigment in the aqueous first base paint is 1 to 30%, and the PWC of the glittering pigment in the aqueous second base paint is 5 It is preferably ˜40%. If the PWC of the glitter pigment in the aqueous first base paint is less than 1%, a sufficient concealment may not be obtained, and if it exceeds 30%, various performances of the coating film may be deteriorated. More preferably, it is 3 to 25%. Further, if the PWC of the glitter pigment in the aqueous second base paint is less than 5%, sufficient brightness may not be obtained, and if it exceeds 40%, the orientation of the glitter pigment is not good and the coating film appearance is deteriorated. There is a fear. More preferably, it is 7 to 30%. Here, the glitter pigment preferably has a flip-flop property. The flip-flop property refers to the degree of change in reflected light intensity when the observation angle (light reception angle) changes.

[(E): PWC ratio of luster pigment contained in water-based first base paint and water-based second base paint]
In the glitter coating film forming method of the present invention, (E): the PWC ratio of the glitter pigment contained in the aqueous first base paint and the aqueous second base paint is (1/4) to (1 / 1.1) is preferable. That is, the PWC of the glitter pigment contained in the aqueous second base paint is always higher than the PWC of the glitter pigment contained in the aqueous first base paint. If the PWC ratio of the bright pigment is less than 1/4, bright unevenness may occur, and if it exceeds 1 / 1.1, sufficient bright pigment orientation may not be obtained. More preferably, it is (1 / 1.5) to (1 / 3.5).

  The water-based first base coating film and the water-based second base coating film are preferably formed by spray coating. However, after the water-based first base coating film is formed, setting is performed, and the water-based second base is wet-on-wet. Form a coating film. After forming the aqueous second base coating film, after setting for 2 minutes, if necessary, preheating is performed at 40 to 80 ° C. for 1 to 10 minutes in a drying furnace to obtain an uncured base coating film.

As the spray gun for performing the spray coating, a rotary atomizing bell type coating machine or an air atomizing type coating machine is preferably used. As a rotary atomizing type bell coating machine, a metallic bell G1-COPES bell (manufactured by ABB Industry) can be mentioned. The rotational speed in the rotary atomization mold is preferably (2-4) × 10 ⁴ rpm, and the discharge amount is preferably 80-250 cc / min.

[Step (3)]
Next, in the glitter coating film forming method of the present invention, in the clear coating zone, in the clear coating zone, the clear coating film is coated on the aqueous second base coating film obtained in the above step (2). It is a process of forming.

  In the second glittering coating film forming method of the present invention, the steps (3) and (4) in the first glittering coating film forming method are omitted, and the process (5) is sequentially performed. .

  In this case, the clear coating film does not cover the underlayer, is a colorless and transparent clear coating film, and may also be a so-called color clear coating film that imparts a translucent feeling. By forming the top clear coating film on the surface, it is possible to improve the gloss and prevent the bright pigment from protruding.

  As the clear paint for forming the clear coating film, those commonly used for top coating can be used. For example, a mixture of at least one thermosetting resin selected from an acrylic resin, a polyester resin, a fluororesin, an epoxy resin, a polyurethane resin, a polyether resin, and a modified resin thereof and the above crosslinking agent may be used. it can.

  These clear paints are blended with additives such as color pigments, extender pigments, modifiers, UV absorbers, leveling agents, dispersants, antifoaming agents, etc., as long as the transparency is not impaired. It is possible. Further, a clear coating containing a carboxyl group-containing polymer and an epoxy group-containing polymer described in JP-B-8-19315 is preferably used from the viewpoint of acid rain countermeasures. Further, the clear coating film can take various forms such as an organic solvent type, an aqueous type, and a powder type. As the organic solvent-type paint or water-based paint, a one-component paint may be used, or a two-component paint such as a two-component urethane resin paint may be used.

  The dry film thickness of the clear coating film is preferably 10 to 60 μm, and if it is out of this range, there is a risk of problems in the coating film appearance and coating workability. More preferably, it is 20-50 micrometers.

[Step (4)]
Next, in step (4) in the first glittering coating film forming method of the present invention, all the uncured coating films obtained by the above steps (1), (2) and (3) are heated and cured at a time. It is a process.

  In order to heat and cure all the uncured coating films obtained by the above steps (1), (2) and (3) at a time, at a predetermined temperature in a drying zone installed next to the clear coating zone. By passing through a drying or curing step for a predetermined time, a glittering coating film composed of multiple layers can be obtained on the surface of the substrate. The predetermined temperature and the predetermined time can be appropriately set according to the types of the water-based first base paint, the water-based second base paint, and the clear paint.

[Step (5)]
Step (5) in the second glittering coating film forming method of the present invention is a step in which all the uncured coating films obtained by the above steps (1) and (2) are heated and cured at a time.

  In order to heat and cure all uncured coating films obtained by the above steps (1) and (2) at a time, a drying or curing step is performed at a predetermined temperature for a predetermined time in a drying zone that is appropriately installed. By passing, the glitter coating film which consists of a multilayer on the said base-material surface can be obtained. The predetermined temperature and the predetermined time can be appropriately set according to the types of the water-based first base paint and the water-based second base paint.

[Painted material]
The coated product of the present invention is coated by the first and second glittering coating film forming methods, and according to the first glittering coating film forming method, It is formed so as to satisfy the following conditions (A) and (B) through the steps (1) to (4) in order, and further satisfy the following conditions (C). Step (1): a step of applying a water-based first base paint to form a first base coating film in the first stage of the base coating zone, step (2): the step (2) in the second stage of the base coating zone A step of applying a water-based second base paint on the first base coating film obtained in 1) to form a second base coating film, step (3): obtained in the above step (2) in the clear coating zone. A step of applying a clear paint on the second base coating film to form a clear coating film, and a step (4): all uncured products obtained by the above steps (1), (2) and (3) Step of heat-curing the coating film at once; Condition (A): 10 to 45% by mass of paint solid content in the aqueous first base paint, and 10 to 40% by mass of paint solid content in the aqueous second base paint , Condition (B): The above water-based first base paint The paint solid content ratio with the aqueous second base paint is (1.1 / 1) to (4/1), condition (C): dry film of the first base paint film and the second base paint film The thickness ratio is (1.5 / 1) to (5/1).

  In addition, according to the second glittering coating film forming method, the following (A) and (B) conditions are sequentially applied to the coating film forming object through the following steps (1), (2) and (5). Preferably, it is formed so as to satisfy the following condition (C). Step (1): a step of applying a water-based first base paint to form a first base coating film in the first stage of the base coating zone, step (2): the step (2) in the second stage of the base coating zone A step of applying a water-based second base paint on the first base coating film obtained in 1) to form a second base coating film, step (5): all obtained by the above steps (1) and (2) A step of heat-curing the uncured coating film at once; Condition (A): 10 to 45% by mass of the solid content of the aqueous first base paint is 10% by weight, and the solid content of the paint in the aqueous second base paint is 10 ~ 40 mass%, condition (B): paint solid content ratio of the aqueous first base paint and the aqueous second base paint is (1.1 / 1) to (4/1), condition (C): The dry film thickness ratio between the first base coating film and the second base coating film is (1 5/1) - (5/1).

  EXAMPLES Next, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited only to these Examples. In addition, unless otherwise indicated, a compounding quantity represents a mass part. The names of raw materials, paints, and equipment represent product names unless otherwise specified.

[Examples 1-16, Comparative Examples 1-5]
[Preparation of coated film forming materials 1-2]
After dull steel plate (length 300 mm, width 100 mm and thickness 0.8 mm) is treated with zinc phosphate, cationic electrodeposition paint (“Power Top V-50”, manufactured by Nippon Paint Co., Ltd.) is dried to a thickness of 25 μm. Electrodeposited. Next, an electrodeposition coating film was obtained by baking at 160 ° C. for 30 minutes. Further, an intermediate coating ("Olga P-5 Sealer" manufactured by Nippon Paint Co., Ltd.) is applied by air spray onto the electrodeposition coating film so that the dry film thickness is 40 μm, and baked at 140 ° C. for 30 minutes. A coating film was formed, and this was designated as a film-formed article 1.

  After a plastic plate (material: polypropylene, length 300 mm, width 100 mm and thickness 3.0 mm) is washed and degreased, “RB116 Primer” (manufactured by Nippon B Chemical Co., Ltd.) as a primer has a dry film thickness of 10 μm. It was spray painted so that Next, the substrate was dried at a surface temperature of 80 ° C. for 10 minutes. This was designated as film-formed product 2.

[Step (1): Formation of first base coating film]
Next, a first base paint in which the following types, the amount of glittering pigment shown in Table 1, and a coloring pigment to be blended as necessary are blended in the first stage of the base coating zone on the coating film formations 1 and 2 is shown. The first base coating film was formed by coating so as to have a dry film thickness shown in FIG. Here, the water-based first base paint blended with the luster pigment is adjusted to the specific values shown in Table 1 based on an acrylic-melamine resin-based paint “AQUAREX AR2100” (manufactured by Nippon Paint Co., Ltd.). However, Example 11 was prepared based on a melamine-carbodiimide acrylic water-based base coating “KX-0077” (manufactured by Nippon B Chemical Co., Ltd.).

[Step (2): Formation of second base coating film]
Next, after setting the aqueous first base coating film for 2 minutes, wet-on-wet, in the second stage of the base coating zone, the types shown below and the amount of glittering pigment shown in Table 1, and a coloring pigment to be blended as necessary The 2nd base paint which blended the additive was applied so that it might become the dry film thickness shown in Table 1, and the 2nd base paint film was formed. Here, the water-based second base paint blended with the luster pigment is adjusted to the specific values shown in Table 1 based on an acrylic-melamine resin paint “AQUAREX AR2100” (manufactured by Nippon Paint Co., Ltd.). However, Example 11 was prepared based on a melamine-carbodiimide acrylic water-based base coating “KX-0077” (manufactured by Nippon B Chemical Co., Ltd.).

[Step (3): Formation of clear coating film] (first glitter coating film forming method)
Next, after setting the second base coating film for 2 minutes, preheat it at 80 ° C. for 3 minutes, and in the clear coating zone, apply the clear coating shown below to a dry film thickness of 35 μm. Formed. The clear paint 1 is an acrylic resin solvent-type clear paint (trade name: “Super Lac O-100 Clear”, manufactured by Nippon Paint Co., Ltd.), and the clear paint 2 is a solvent comprising a blend of a carboxyl group-containing polymer and an epoxy group-containing polymer. Type clear paint (trade name: “McFlow O-330 Clear”, manufactured by Nippon Paint Co., Ltd.). The substrate 2 was spray-coated with an acrylic urethane clear coating 3 (trade name: “R290 Clear”, manufactured by Nippon Bee Chemical Co., Ltd.) so that the dry film thickness was 30 μm.

[Step (4): Heat curing all uncured coating films] (first glitter coating film forming method)
The formed clear coating film was set at room temperature for 10 minutes and baked at a temperature of 140 ° C. for 30 minutes. In the case of the substrate 2, the formed clear coating film was set at room temperature for 10 minutes and baked at 80 ° C. for 20 minutes. The glitter of the obtained multilayer coating film was evaluated by the following evaluation method, and the results are shown in Table 1.

[Step (5): Heat curing all uncured coating films] (second glitter coating film forming method)
The formed base coating film was baked at a temperature of 140 ° C. for 30 minutes. The glitter of the obtained multilayer coating film was evaluated by the following evaluation method, and the results are shown in Table 1.

[Evaluation methods]
Finished appearance: When the test plate was viewed almost directly in front (highlighted portion) and at an angle of about 15 degrees (shaded portion), the glittering feeling indicating the quality of the metallic appearance and the appearance of the coating film were visually evaluated. It is better if there is no glitter.

A: There is no glittering feeling, no bright unevenness or orientation degradation is observed, and an excellent metallic appearance is achieved.
○… There is no sparkle and it has a metallic appearance.
Δ: The shade part has a glittery feeling.
X: The highlight part and the shade part have a glittering feeling. Finished in normal metallic tone. Or brightness unevenness and orientation deterioration are recognized.

  FF effect: Visually evaluated the magnitude of the difference in brightness when the test plate was viewed almost in front (highlight portion) and at an angle of about 15 degrees (shade portion).

◎ ・ ・ ・ The difference in brightness depending on the angle is very large.
○: There is a large difference in brightness depending on the angle.
Δ: Lightness difference that varies depending on the angle is small.
X: Slight difference in brightness depending on the angle. Finished in normal metallic tone.

  The types of glitter pigments, color pigments, and additives in Table 1 were as follows.

[Illuminating pigment]
1: Aluminum flake pigment; aluminum paste MH-8801 (manufactured by Asahi Kasei Corporation).
2: Aluminum flake pigment; Alpaste 91-0562 (manufactured by Toyo Aluminum Co., Ltd.).
3: Interference mica pigment; Xirallic T60-23WIII (manufactured by Merck Japan).

[Coloring pigments]
1: Carbon black pigment; MA-100 (manufactured by Mitsubishi Chemical Corporation).
2: Phthalocyanine blue pigment; cyanine blue G314 (manufactured by Sanyo Chemical Industries).

[Additive]
1: Fluorinated alkyl carboxylate; Florard FC-129 (manufactured by Sumitomo 3M).
2: Organic modified polysiloxane; BYK-341 (manufactured by Big Chemie Japan).

  As is apparent from the results in Table 1, this example is an aluminum flake having a metallic luster that has a very small particle feeling and is formed by the glittering coating film forming method of the present invention. The pigments showed a metallic appearance with no uneven brightness, and the mica pigments having interference properties improved flip-flop properties. On the other hand, the comparative example did not express the target design.

Claims (6)

A glittering coating film forming method that satisfies the following conditions (A) and (B) through the following steps (1) to (4) in order,
Step (1): In the first stage of the base coating zone, a step of applying a water-based first base glitter paint to form a first base coating film,
Step (2): In the second stage of the base coating zone, a step of coating the water-based second base glittering paint on the first base coating film obtained in the step (1) to form a second base coating film. ,
Step (3): In the clear coating zone, a step of applying a clear paint on the second base coating film obtained in the step (2) to form a clear coating film, and
Step (4): a step of heat-curing all uncured coating films obtained by the steps (1), (2) and (3) at a time;
Condition (A): 10 to 45% by mass of paint solids in the aqueous first base glitter paint, 10 to 40% by mass of paint solids in the aqueous second base glitter paint,
Condition (B): The paint solid content ratio between the water-based first base glitter paint and the water-based second base glitter paint is (1.1 / 1) to (4/1). A glittering coating film forming method that satisfies the following conditions (A) and (B) through the following steps (1), (2) and (5) in order,
Step (1): In the first stage of the base coating zone, a step of applying a water-based first base glitter paint to form a first base coating film,
Step (2): In the second stage of the base coating zone, a step of coating the water-based second base glittering paint on the first base coating film obtained in the step (1) to form a second base coating film. ,and,
Step (5): a step of heat-curing all uncured coating films obtained by the steps (1) and (2) at a time;
Condition (A): The solid content of the aqueous first base glitter paint is 10 to 45% by mass, the solid content of the aqueous second base glitter paint is 10 to 40% by mass,
Condition (B): The paint solid content ratio between the water-based first base glitter paint and the water-based second base glitter paint is (1.1 / 1) to (4/1). The method for forming a glittering coating film according to claim 1 or 2, further satisfying the following condition (C):
Condition (C): The dry film thickness ratio between the first base coating film and the second base coating film is (1.5 / 1) to (5/1). The glitter coating film forming method according to any one of claims 1 to 3, further satisfying the following conditions (D) and (E):
Condition (D): The pigment mass concentration (hereinafter referred to as “PWC”) of the glitter pigment in the aqueous first base glitter paint is 1 to 30%, and the glitter pigment in the aqueous second base glitter paint. PWC is 5-40%,
Condition (E): The PWC ratio of the glitter pigment contained in the water-based first base glitter paint and the water second base glitter paint is (1/4) to (1 / 1.1).   The glitter according to any one of claims 1 to 4, wherein the water-based second base glittering paint contains 0.1 to 5 parts by mass of a fluorine-based or silicone-based additive with respect to 100 parts by mass of the vehicle solid part. -Forming coating film forming method. 6. A coated product coated by the method for forming a glittering coating film according to any one of claims 1 to 5.