JPWO2007148530A1 - Powder coating, powder coating manufacturing method, and coating film forming method using powder coating - Google Patents

Abstract

A powder paint containing a base paint powder (A), a flaky glitter pigment (B), and a binder (C), wherein the binder (C) comprises dicyclopentadiene and other polymerizable monomers and / or Or a hydrogenated resin obtained by copolymerizing with an oligomer and hydrogenated by 80% or more, and the flake-like glitter pigment (B) is bonded to the base coating powder (A) via the binder (C). A powder coating, a method for producing the same, and a method for forming a coating film using the powder coating. It is possible to obtain a coating film that is free from unevenness and rough skin and has excellent design properties.

Description

  The present invention relates to a powder coating material capable of obtaining a coating film excellent in design without occurrence of unevenness or rough skin, a method for producing the same, and a coating film forming method using the powder coating material.

Conventionally, powder coatings are widely used for outdoor or indoor applications in the field of industrial products such as home appliances, automobile parts, vehicles, office supplies, steel furniture, and building materials. In such applications, in recent years, various studies have been conducted on powder coatings for glittering finishes using flaky glitter pigments from the viewpoint of imparting high design properties.
As a method for producing such a powder coating material, a method of mixing a flaky pigment made of aluminum or the like with a coating material, specifically, a coating composition containing an additive such as a flaky pigment or a coloring pigment is melted. A method of kneading and then pulverizing (kneading and pulverizing method), a method of producing a powder coating material containing no flaky pigment in advance by a kneading and pulverizing method, and a method of mixing this powder coating material and the flaky pigment (dry blending method), etc. Has been adopted.
However, in the case of the kneading and pulverizing method, the flake pigment is uniformly dispersed in the coating film-forming resin by kneading, that is, by mixing the composition while applying a shearing force at a temperature at which the resin melts. There is a problem that the pigment is easily damaged. For example, when aluminum powder is used as the flake pigment, the aluminum powder is destroyed by the shearing force applied during melt-kneading, and the aluminum powder turns black or gray. Even if a powder coating containing such broken aluminum powder is applied, it is no longer possible to obtain a glittering coating film having a metallic luster.
On the other hand, in the dry blend method, a powder coating composition containing a resin and, if necessary, an additive such as a color pigment is uniformly kneaded in advance to obtain coating particles, which are then combined with a flaky pigment, This is a method for producing a powder coating material by simply stirring and mixing without melting the resin inside. According to this method, since the flaky pigment is not exposed to high temperature and is not subjected to shearing force, it is possible to produce a glittering powder paint without damaging the flaky pigment. it can. However, the glittering powder paint produced by this method has some problems in coating workability and coating film characteristics because the bonding force between the paint particles and the flaky pigment is weak. In other words, when aluminum powder is used as the flake pigment, the paint particles and aluminum powder are separated due to the difference in the charging characteristics between the paint particles in the powder paint and the aluminum powder when using a corona charging type electrostatic coating machine. Then, the aluminum powder adheres to the voltage application needle located at the tip of the corona charging type electrostatic coating machine and the periphery thereof. As a result, the amount of aluminum powder contained in the coating film is less than the amount originally contained in the glittering paint, and a coating film having sufficient metallic luster and excellent design properties cannot be obtained. With pearl pigments, the above phenomenon becomes more prominent, and only a coating film with poor design can be obtained. In addition, as described above, the paint that did not adhere to the object to be coated has a flaky pigment content ratio that is lower than the original one, and since it is inferior in design, it cannot be reused. In the production process, it becomes a large financial burden. In addition, when an adherent such as aluminum powder adhered to the needle of the electrostatic coating machine or its surroundings peels off from the tip of the electrostatic coating machine and adheres to the object to be coated, convex bumps (spits) are formed on the painted surface. This causes a problem that the appearance of the coating film is significantly impaired.
As a paint manufacturing method that can solve the problems caused by the breakage of the flake-like glitter pigment and obtain a coating film having high design properties, the paint powder and the flake-like glitter pigment are mixed, A method of mixing a binder that binds to a flaky glitter pigment has been proposed (see, for example, Japanese Patent Application Laid-Open Nos. 2004-107487 and 2004-175813).

According to these methods, the coating powder is excellent in workability without separation of the coating powder and the flaky glitter pigment, and a coating film having excellent design properties can be formed. Depending on the type, the formed coating film may have unevenness and rough skin, resulting in inferior finished appearance such as gloss and smoothness.
Therefore, an object of the present invention is to provide a powder coating material capable of obtaining a coating film excellent in design without occurrence of unevenness or rough skin, a manufacturing method thereof, and a coating film forming method using the powder coating material There is to do.
The powder coating material of the present invention achieves the above object, and is a powder coating material containing a base coating powder (A), a flaky glitter pigment (B), and a binder (C). The binder (C) includes a hydrogenated resin obtained by copolymerizing dicyclopentadiene and other polymerizable monomers and / or oligomers and hydrogenated by 80% or more, and the flake-like glitter pigment (B) is bound. It is characterized by being bonded to the base paint powder (A) through the agent (C).
According to the present invention, by using a specific binder, the paint powder and the flake-like glitter pigment are uniformly bonded regardless of the type of constituent resin component of the paint powder, and there is no occurrence of unevenness or rough skin. A coating film excellent in design can be obtained.

In the present invention, the “paint powder” used as the base paint powder (A) is conventionally used in powder paints, and includes a coating film-forming resin, and a color pigment or extender pigment added as necessary. A coating composition containing other additives is melt-kneaded, pulverized and powdered, and can be produced by a known method.
As the “coating film-forming resin” used for the coating powder, thermosetting resins and thermoplastic resins that have been conventionally used as coating film forming resins for powder coatings can be used, but thermosetting resins are generally used. Is. Examples of such a “thermosetting resin” include a combination of (i) a hydroxyl group-containing solid resin and a curing agent having a functional group that undergoes a curing reaction with the hydroxyl group by heat, and (ii) a carboxyl group-containing solid resin; , A combination of the carboxyl group and a curing agent having a functional group that undergoes a curing reaction by heat, and (iii) a combination of an epoxy group-containing solid resin and a curing agent having a functional group that undergoes a curing reaction by the epoxy group and heat. be able to. The “solid” of the resin here means a solid at room temperature, and preferably has a softening point of 80 to 200 ° C. Further, the curing agent may be solid or liquid, but a solid one is preferably used.
As the “hydroxyl group-containing solid resin”, for example, resins used in known powder coating materials such as a hydroxyl group-containing acrylic resin and a hydroxyl group-containing polyester resin can be used. Examples of the “curing agent having a functional group that undergoes a curing reaction with a hydroxyl group and heat” that can be used in combination with the hydroxyl group-containing solid resin are used in known powder coatings such as blocked polyisocyanate compounds and aminoplast resins. A curing agent is mentioned.
As the “carboxyl group-containing solid resin”, for example, resins used in known powder coating materials such as a carboxyl group-containing acrylic resin and a carboxyl group-containing polyester resin can be used. Examples of the “curing agent having a functional group that undergoes a curing reaction with a carboxyl group by heat” that can be used in combination with this carboxyl group-containing solid resin include, for example, bisphenol A to epichlorohydrin type epoxy resin, alicyclic epoxy resin, and novolac type epoxy resin. And curing agents used in known powder coatings such as epoxy resins such as epoxy group-containing acrylic resins and hydroxyalkylamide compounds.
Examples of the “epoxy group-containing solid resin” include resins used in known powder coating materials such as bisphenol A to epichlorohydrin type epoxy resin, alicyclic epoxy resin, novolac type epoxy resin, and epoxy group-containing acrylic resin. Can be used. Examples of the “curing agent having a functional group that undergoes a curing reaction with an epoxy group and heat” that can be used in combination with the epoxy group-containing solid resin include, for example, a carboxyl group-containing polyester resin, an organic acid polyhydrazide compound, an imidazole compound, a dicyandiamide compound, Examples thereof include curing agents used in known powder coating materials such as polycarboxylic acid compounds and acid anhydrides.
Among the thermosetting resins exemplified above, those having the following combinations are preferable because they are excellent in coating film performance (such as weather resistance) and finish properties (such as design and smoothness).
(Ii-1) Combination of carboxyl group-containing polyester resin and hydroxyalkylamide compound The carboxyl group-containing polyester resin used here has a resin acid value of 20 to 200 mgKOH / g, preferably about 25 to 150 mgKOH / g. A softening point of about 50 to 150 ° C., preferably about 70 to 140 ° C. is preferred. As the carboxyl group-containing polyester resin, specifically, the above-described aromatic or alicyclic dicarboxylic acid, the above-described dihydric alcohol, monocarboxylic acid such as benzoic acid as necessary, (anhydrous) trimellitic acid, etc. Examples of resins obtained by appropriately reacting a trivalent or higher carboxylic acid such as trimethylol ethane, trimethylol propane, glycerin, pentaerythritol or the like with a trivalent or higher carboxylic acid in the above-described range of the acid value. be able to.
Examples of the hydroxyalkylamide compound include N, N′-di (β-hydroxyethyl) acetamide, bis (β-hydroxyethyl) adipamide, bis (β-hydroxypropyl) adipamide, bis [N, N′-di ( β-hydroxyethyl)] adipamide, bis [N, N′-di (β-hydroxypropyl)] adipamide and the like are suitable.
The ratio of the carboxyl group-containing polyester resin to the hydroxyalkylamide compound is such that the β-hydroxylalkylamide group is 0.5 to 1.5, preferably 0.8 to one carboxyl group of the carboxyl group-containing polyester resin. A range of 1.2 is preferred.
(Ii-2) Combination of carboxyl group-containing polyester resin and epoxy resin Examples of the carboxyl group-containing polyester resin used here include the same as (ii-1) above. The epoxy resin preferably has an epoxy equivalent of 200 to 3000, preferably 300 to 2000, and a softening point of about 20 to 200 ° C, preferably about 30 to 150 ° C. Specific examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol B type epoxy resin, acrylic type epoxy resin, brominated epoxy resin, and cycloaliphatic epoxy resin (cyclohexene oxide group). , Epoxy resins containing a tricyclodecene oxide group, a cyclopentene oxide group, and the like. Of these, acrylic epoxy resins are preferred from the viewpoint of weather resistance.
The use ratio of the carboxyl group-containing polyester resin and the epoxy resin is a range in which the epoxy group is 0.5 to 1.5, preferably 0.8 to 1.2 per carboxyl group of the carboxyl group-containing polyester resin. Is preferred.
Examples of the “color pigment” used in the coating powder include titanium dioxide, iron oxide, dial, carbon black, phthalocyanine blue, phthalocyanine green, quinacridone pigment, isoindolinone pigment, azo pigment, acetolone pigment, various types Mention may be made of inorganic color pigments such as calcined pigments or organic color pigments. Examples of the “extreme pigment” added to the coating powder include calcium carbonate, glass fiber, silica, talc, barium sulfate, and kaolin. Furthermore, rust preventive pigments such as zinc powder and aluminum dihydrogen phosphate can be used as necessary. Incidentally, these pigments are merely examples, and the present invention is not limited to the above description.
Examples of the “additive” include a surface conditioner, a curing accelerator, an anti-sagging agent, an ultraviolet absorber, a light stabilizer, an antioxidant, and a dye, which can be used as necessary.
A coating composition containing the resin as described above, a color pigment added as necessary, an additive, and the like is prepared, and these are kneaded and homogenized at a temperature at which the resin melts. The obtained paint pellets are pulverized and classified to produce a base paint powder having an average particle size of about 10 to 100 μm, preferably 20 to 60 μm.
In the present invention, the “average particle size” is a value obtained by measuring the particle size distribution of the base paint powder or pigment particles after classification with a general particle size distribution meter, and obtaining an integrated value 50 from the small particle size side obtained from the obtained result. % Particle size (D ₅₀ ). Such a particle size distribution can be measured by a diffraction or scattering intensity pattern generated by applying light to the particles. This is because the intensity pattern depends on the particle size. Examples of the particle size distribution meter used here include Microtrac 9220FRA and Microtrac HRA manufactured by Nikkiso Co., Ltd., and COULTER MURTISIZER manufactured by Beckman Coulter. An example of the measurement method will be specifically described. After 30 ml of water is put into a container, 0.01 to 0.1 g of a neutral detergent is added and stirred, and then 0.01 to 0.2 g of a measurement sample is put and stirred. While being dispersed by applying ultrasonic waves for 2 minutes, this may be measured by the particle size distribution meter.
In the present invention, the flaky glitter pigment (B) is not particularly limited as long as it reflects the received light and gives the coating film a design feeling such as a metallic feeling or a pearly feeling (light interference pattern). Preferred examples include metal powders such as aluminum powder, metal flakes such as stainless steel flakes, mica, micacious iron oxide (MIO, flaky iron oxide), glass flakes, and pearl pigments such as pearl mica. The 1 type (s) or 2 or more types selected can be mentioned. Here, for each bright pigment, those that have been conventionally known surface treatment, further resin-coated aluminum powder, silica-coated aluminum powder, fluorine compound-coated aluminum powder, titanium-coated mica, hasteroid-coated glass flakes, etc. Those coated with them are also included.
The flaky glitter pigment (B) preferably has an average particle size of 2 μm to 100 μm, more preferably 3 μm to 80 μm. Moreover, suitable thickness is 0.01 micrometer or more and 10 micrometers or less, More preferably, they are 0.05 micrometer or more and 6 micrometers or less. More specifically, in the case of aluminum flakes, the average particle diameter is preferably 2 μm or more and 50 μm or less, and the thickness is preferably 0.05 μm or more and 5 μm or less. In the case of pearl pigments, the average particle diameter is 5 μm. As described above, it is preferable that the thickness is 70 μm or less and the thickness is 0.1 μm or more and 5 μm or less.
The proportion of the pigment (B) in the whole powder coating is 0.1 to 20% by mass, preferably 0.5 to 15% by mass from the viewpoint of design and the like.
In the present invention, the binder (C) contains a hydrogenated resin obtained by copolymerizing dicyclopentadiene and other polymerizable monomers and / or oligomers and hydrogenating 80% or more. From the viewpoint of finishing, it is desirable to contain 50% by mass or more, preferably 60% by mass or more.
Examples of other polymerizable monomers and / or oligomers include C _{4 to} C ₁₀ olefins copolymerizable with dicyclopentadiene, and the binding ability of the base coating powder (A) and the pigment (B). From the viewpoint, it is particularly preferable to include styrene, styrene derivatives such as styrene, α-methylstyrene, β-methylstyrene, vinyltoluene, oligomers thereof, and the like.
The hydrogenation rate of the hydrogenated resin is 80% or more, preferably 90% or more, more preferably 95% or more, from the viewpoint of the weather resistance of the formed coating film. It can be obtained from the bromine number of the resin after the addition. In addition, a bromine number can be measured by the method based on JIS. The softening point of the hydrogenated resin is preferably about 50 to 200 ° C, preferably about 70 to 150 ° C.
Examples of the hydrogenated resin as described above include “Imabe P-90” (hydrogenation rate: 100%, softening point: 90 ° C.), “Imabe P-100” (hydrogenation rate: 100%, softening point: 100 ° C.), “Imabe P-115” (hydrogenation rate: 100%, softening point: 115 ° C.), “Iimab P-125” (hydrogenation rate: 100%, softening point: 125 ° C.), “Imabe P- 140 ”(hydrogenation rate: 100%, softening point: 140 ° C.),“ Imabe S-100 ”hydrogenation rate: 90%, softening point: 100 ° C.,“ Imabe S-110 ”(hydrogenation rate: 90% , Softening point: 110 ° C.), “Imabe S-125” (hydrogenation rate: 90%, softening point: 125 ° C.), “Imabe S-140” (hydrogenation rate: 90%, softening point: 140 ° C.) ( As mentioned above, Idemitsu Kosan Co., Ltd.) Goods, and the like.
In addition to the hydrogenated resin, the binder (C) may be, for example, a chroman / indene resin, a terpene resin, a terpene / phenol resin, an aromatic hydrocarbon-modified terpene resin, or a hydrogenated terpene resin. Resin, hydrogenated terpene / phenolic resin, rosin resin, hydrogenated rosin ester resin, rosin modified phenolic resin, alkylphenolic resin, alkylphenol / acetylene resin, alkylphenol / formaldehyde resin, styrene resin, aliphatic Resins such as petroleum resins, alicyclic petroleum resins, copolymer petroleum resins, aromatic petroleum resins, and waxes such as polyethylene wax can be included.
The proportion of the binder (C) in the whole powder coating is 0.1 to 5% by mass, preferably 0.5 to 3% by mass, so that the base coating powder (A) and the pigment (B) are combined. It is desirable from the viewpoints of the properties and the finished appearance of the formed coating film.
The powder coating material of the present invention may further contain an additive according to necessity or purpose. Examples of such additives include additives for improving paint fluidity such as silica particles and aluminum oxide.
The method for producing a powder coating material of the present invention generally comprises a step of mixing a base coating powder (A) and a pigment (B), and a liquid binder in which the binder (C) is dissolved in an organic solvent is mixed with the mixture. A process and a drying process. Preferably, it is desirable to first thoroughly mix the paint components, particularly the base paint powder and the pigment particles. If the mixing is insufficient, the base paint powder or pigment particles are unevenly distributed, and the ratio of the base paint powders or the pigment particles bonding to each other increases, so that it is difficult to obtain a coating film with high design properties. is there.
The mixing method is not particularly limited as long as the paint constituents can be sufficiently mixed, but it is generally performed using a mechanical stirring mixer or an airflow stirring mixer. As a mixing condition using the mechanical stirring type mixer, a condition in which the constituent components such as the base paint powder and the pigment particles can be uniformly mixed and the pigment particles are not damaged is adopted. As a rotational speed of the stirring mixer that satisfies such conditions, a peripheral speed of 3 to 6 m / s is preferable.
In the method for producing a powder coating material according to the present invention, after the base coating material powder and the pigment particles are uniformly mixed, a liquid binder obtained by dissolving the binder in an organic solvent is uniformly mixed with the base coating material powder and the pigment particles. . The liquid binder is required to uniformly adhere to the base paint powder and the pigment particles, and in order to achieve such uniform adhesion, it is preferable to add the liquid binder by dropping or spraying. It is preferable to carry out by spraying.
The manufacturing method of the powder coating material of this invention includes a drying process. The drying step is performed in order to secure the bond between the base paint powder and the pigment particles by volatilizing the organic solvent in the liquid binder. The means for drying is not particularly limited. For example, supply of air can be mentioned, and considering the manufacturing work efficiency, it is preferable to use heated air as the air. The temperature of the air may be determined as appropriate, but it is necessary that it is at least lower than the softening point of the powder coating resin component. This is because the resin softens when the softening point is reached and blocking of the powder particles occurs. Here, the “softening point” in the present invention is, for example, heated using a ring and ball type automatic softening point tester (manufactured by Meihosha Seisakusho Co., Ltd.) in a glycerin heating bath at a heating rate of 3 ° C./min. It can be measured as the temperature (° C.) when the ball is softened and the sphere falls. As the temperature of the dry air, generally 20 to 120 ° C. can be adopted, and more preferably 40 to 100 ° C. In addition, the air supply timing may be appropriately determined. For example, heated air may be supplied after the binder is added and then cooled, or heated air may be supplied while the binder is added, and then cooled. Also good.
The powder coating produced as described above can be applied to the object to be coated by electrostatic coating method, fluidized dipping method, spraying method, in-mold method, etc., hot air furnace, infrared furnace, induction heating furnace A cured coating film can be formed by baking with, for example.
In the powder coating according to the present invention, since the base coating powder and the pigment particles are strongly bonded, these components are separated even when coating by the electrostatic coating method, and the coating machine, particularly the coating machine tip portion. The coating operation can be performed stably.
In the present invention, the powder coating can be applied to an object to be coated made of a metal material to form a coating film.
The type of metal material is not particularly limited. For example, ferrous metal materials such as the most versatile steel and alloy steel, non-ferrous metal materials and alloys such as aluminum, stainless steel, zinc, tin, copper, titanium, magnesium, and brass. Furthermore, plated metal materials such as galvanized steel sheets and tin-plated steel sheets, surface-treated metal materials subjected to chemical treatment of chromic acid or phosphate, titanium, zircon, organic metal salts, and other non-chromium Examples thereof include aluminum metal materials and alloys subjected to anodizing treatment and sealing treatment.
The object to be coated made of the above metal material may reach the final product after undergoing the painting process, but may be a part or a production intermediate of the final product, and if it requires painting. The name does not matter. In addition, “consisting of a metal material” means that the painted surface is mainly composed of a metal material, and a part of the surface may have something other than a metal material such as a resin, Further, the portion other than the surface may be made of a material other than the metal material.
The film thickness of the coating film to be formed is the film thickness after baking, and is usually 30 to 250 μm, and preferably in the range of 40 to 150 μm. The baking condition of the powder coating is generally that the surface temperature of the metal material is 130 to 350 ° C., preferably 140 to 250 ° C., and is 30 seconds to 60 minutes, preferably 1 to 50 minutes.
Hereinafter, the present invention will be described in more detail with reference to examples. In the examples, “parts” and “%” indicate “parts by mass” and “% by mass” unless otherwise specified.
Powder coating production

Carboxyl group-containing polyester resin “Fine Dick M8962” (manufactured by Dainippon Ink and Chemicals, trade name, softening temperature 112 ° C., acid value 35 mg KOH / g) 95 parts, hydroxyalkylamide curing agent “XL-552” (manufactured by MMS) , Trade name, β-hydroxyethyl adipamide), melt kneaded with an extruder, cooled, finely pulverized with an atomizer, filtered through 150 mesh to produce a base coating powder (A-1) did.
As a binder, 1 part of dicyclopentadiene-based hydrogenated resin “Imabe P-125” (trade name, hydrogenation rate 100%, softening point 125 ° C., manufactured by Idemitsu Petrochemical Co., Ltd.) was dissolved in 20 parts of normal heptane. A binder solution (C-1) was obtained.
4 parts of flake-like glitter pigment “PCF1440” (trade name, resin-coated aluminum powder, manufactured by Toyo Aluminum Co., Ltd.) are added to 100 parts of the above base coating powder (A-1), and a high speed mixer “LFS-GS-2J” is added. After mixing with Fukae Pautech Co., Ltd. for 2 minutes, the binder solution (C-1) was sprayed into the high speed mixer while mixing, and further stirred and mixed for 20 minutes. Thereafter, the jacket in the mixer was heated to 30 ° C. and dried while reducing the pressure with a vacuum pump. The obtained powder was passed through a screen having an opening of 100 μm to obtain 98.5 parts of powder coating material.

77 parts of carboxyl group-containing polyester resin “Fine Dick M8962”, epoxy resin “Fine Dick A-229-30” (trade name, softening temperature 109 ° C., epoxy equivalent 525 g / eq, manufactured by Dainippon Ink & Chemicals, Inc.) The mixture was melt-kneaded with an extruder, cooled, then finely pulverized with an atomizer, and filtered with 150 mesh to produce a base coating powder (A-2).
A powder paint was obtained in the same manner as in Example 1 except that the obtained base paint powder (A-2) was used.
Comparative Example 1
As a binder, 1 part of a terpene / phenolic hydrogenated resin “YS-Polystar TH-130” (manufactured by Yashara Chemical Co., Ltd., softening point: 130 ° C.) is dissolved in 20 parts of normal heptane to obtain a binder solution (C-2). Obtained.
A powder coating material was obtained in the same manner as in Example 1 except that the obtained binder solution (C-2) was used.
Comparative Example 2
As a binder, 1 part of hydrogenated terpene resin “Clearon P-125” (manufactured by Yasuhara Chemical Co., Ltd., softening point 125 ° C.) was dissolved in 20 parts of normal heptane to obtain a binder solution (C-3).
A powder coating material was obtained in the same manner as in Example 1 except that the obtained binder solution (C-3) was used.
Comparative Example 3
As a binder, 1 part of dicyclopentadiene resin “Marcaretz M-845A” (manufactured by Maruzen Petrochemical Co., Ltd., trade name, softening point 145 ° C., not hydrogenated) is dissolved in 20 parts of normal heptane. A solution (C-4) was obtained.
A powder coating was obtained in the same manner as in Example 1 except that the obtained binder solution (C-4) was used.
Comparative Example 4
A powder coating material was obtained in the same manner as in Example 1 except that no binder was used.

As a binder, a binder solution in which 1 part of a dicyclopentadiene-based hydrogenated resin “Imabe P-125” and 0.5 part of a hydrogenated terpene resin “Chlorian P-125” are dissolved in 19.5 parts of normal heptane ( C-5) was obtained.
A powder coating material was obtained in the same manner as in Example 1 except that the obtained binder solution (C-5) was used.

A powder coating material was obtained in the same manner as in Example 2 except that the binder solution (C-5) was used.
Coating test Using each of the powder coatings obtained in the above Examples and Comparative Examples, the cured film thickness is about 50 μm on a SPCC steel plate (0.8 × 70 × 150 mm) subjected to chemical conversion treatment with zinc phosphate. In this manner, electrostatic powder coating was performed and heated at 180 ° C. for 30 minutes to prepare a test coating plate. Each obtained test coating board was used for the following evaluation test. The results are shown in Table 1. In addition, the compounding quantity of Table 1 is the quantity mix | blended with the mass part.
Evaluation Test Method Finished Appearance: The finished appearance of the coating surface of each test coating plate was evaluated with respect to glossiness and smoothness according to the following criteria.
○: Good, Δ: Slightly poor, ×: Poor The metallic feeling was evaluated according to the following criteria.
○: Uniform state without metallic unevenness and rough skin, △: Metallic unevenness and rough skin appear slightly, ×: Metallic unevenness and rough skin occur, and metallic feeling is poor. It used for the test and was immersed in 40 degreeC water for 120 hours after that, and the coating surface immediately after raising was evaluated visually.
○: Good, △: Slightly poor (slightly yellowing, choking, etc.), X: Poor (severe yellowing, choking, etc.)

  INDUSTRIAL APPLICATION Since this invention makes it possible to obtain the coating film which did not generate | occur | produce unevenness and rough skin, etc., and was excellent in the designability, it is industrially useful.

Claims (9)

A powder paint containing a base paint powder (A), a flaky glitter pigment (B), and a binder (C), wherein the binder (C) comprises dicyclopentadiene and other polymerizable monomers and / or Or a hydrogenated resin obtained by copolymerizing with an oligomer and hydrogenated by 80% or more, and the flake-like glitter pigment (B) is bonded to the base coating powder (A) via the binder (C). Powder paint characterized by. The powder coating material according to claim 1, wherein a ratio of the binder (C) to the whole powder coating material is 0.1 to 5% by mass. The powder coating material according to claim 1 or 2, wherein a ratio of the pigment (B) to the whole powder coating material is 0.1 to 20% by mass. The powder coating material according to any one of claims 1 to 3, wherein the base coating material powder (A) is a coating powder containing a polyester resin. The powder coating material according to claim 4, wherein the polyester resin has a carboxyl group. The powder coating material according to any one of claims 1 to 5, wherein the base coating material powder (A) is a coating powder containing an epoxide resin as a curing agent. The powder coating material according to any one of claims 1 to 5, wherein the base coating material powder (A) is a coating powder containing hydroxyalkylamide as a curing agent. A method for producing a powder coating material according to any one of claims 1 to 7, comprising a step of mixing the base coating powder (A) and the pigment (B), and a liquid in which the binder (C) is dissolved in an organic solvent. A method for producing a powder coating material, comprising: a step of mixing a binder with the mixture; and a step of drying. A coating film forming method, wherein the powder coating material according to any one of claims 1 to 7 is coated with an electrostatic powder on an object made of a metal material to form a coating film.