JP2001031894A - Method for forming luminous coating film and luminous coated article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a luminous coating film which has a color-flopping effect and a good luminous property, by sequentially forming a luminous coating layer, an interference clear coating layer and a top clear coating layer on a substrate. SOLUTION: This method for forming a luminous coating film comprises forming a luminous coating layer containing a luminous pigment [preferably a compound of the formula: M.Al2O4 (M is Ca, Sr or Ba)] on a substrate, forming an interference clear coating layer containing an interference pigment (preferably mica pigment, alumina flake pigment, silica flake pigment) on the formed luminous coating layer, and further forming a top clear coating layer on the formed interference clear coating layer. Before the luminous coating layer is formed, a pale color base coating layer is preferably formed. A transparent base coating film is also formed by a back coating method comprising forming an interference clear coating layer on a transparent substrate, forming a luminous coating layer on the formed interference clear coating layer, and preferably further forming a pale color base coating layer on the formed luminous coating layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a luminous coating film and a luminous coating obtained by the method.

[0002]

2. Description of the Related Art JP-A-3-126772 discloses that a first base coating film containing a fluorescent pigment is formed on an undercoating film or an intermediate coating film, and at least mica fragments are formed on the first base coating film. A method for forming a second base coating film containing a diffuse reflection material made of and forming a clear coating film on the second base coating film is described. Japanese Patent Application Laid-Open No. H11-78402 describes an automobile wheel exterior part in which a coating film containing a luminous pigment is partially formed.

[0003]

Problems to be Solved by the Invention
In Japanese Patent Publication No. 2, Calcium sulfide / bismuth (CaS / Bi) and zinc cadmium sulfide / copper ((Z
n, Cd) S / Cu) and the like, and mica fragments and aluminum fragments are mentioned as the irregular reflection material. These fluorescent pigments have a short afterglow time, a weak luminous property, and exhibit fluorescence when exposed to light, but have a problem that light emission is insufficient when not exposed to light. I have. In addition, the coating layer containing the diffusely reflective material on the fluorescent layer,
This is to diffuse the incident light and cover the weather resistance of the fluorescent pigment. In JP-A-11-78402, there is a problem that a metallic design cannot always be obtained sufficiently because the metallic base coating layer is formed below the light emitting clear coating layer.

[0004] Therefore, the problem to be solved by the present invention is:
In the daytime or in bright conditions,
A color flop effect in which the hue changes is obtained, and at night or in a dark situation, a long time, a good luminous property that allows the visual recognition of the coating film formed as the luminous coating layer without exposure to light,
An object of the present invention is to provide a method for forming a luminous coating film and a luminous coating obtained by the method.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies in view of the above-mentioned problems, and as a result, have reached the present invention. 1. After forming a phosphorescent coat layer containing a luminous pigment on a substrate, forming an interference clear coat layer containing an interference pigment on the luminous coat layer, and further forming a top clear coat layer thereon Luminescent coating film forming method. 2. The method for forming a luminous coating film, wherein a light-colored base coat layer is formed before the luminous coating layer is formed. 3. A method for forming a luminous coating film, comprising: forming an interference clear coat layer containing an interference pigment on a transparent substrate, and then forming a luminous coat layer containing a luminous pigment on the interference clear coat layer. 4. The method for forming a luminous coating film, wherein a light-colored base coat layer is formed after the formation of the luminous coating layer. 5. The above method for forming a luminous coating film, wherein the luminous pigment is a compound represented by M.Al ₂ O ₄ (wherein M is at least one of Ca, Sr and Ba). 6. The above-mentioned method for forming a light-emitting coating film, wherein the interference pigment is at least one pigment selected from mica pigment, alumina flake pigment, silica flake pigment, titanium flake pigment, and hologram pigment. 7. A luminous coating product obtained by the luminous coating film forming method.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail.

First Method for Forming Luminescent Coating Film The first method for forming a luminous coating film according to the present invention comprises, as shown in FIG. 1, a luminous pigment layer containing a luminous pigment on a substrate (11). After forming 13), an interference clear coat layer (14) containing an interference pigment is formed on the luminous coat layer, and a top clear coat layer (15) is further formed thereon. Preferably, the phosphorescent coating layer (1
Before forming 3), a light-colored base coat layer (12)
Is formed.

Substrates The above-mentioned substrates include metals such as iron, aluminum, copper and alloys thereof; inorganic materials such as glass, cement and concrete; polyethylene resins and polypropylene resins;
Ethylene-vinyl acetate copolymer resin, polyamide resin,
Resins such as acrylic resin, vinylidene chloride resin, polycarbonate resin, polyurethane resin, epoxy resin, and various plastic materials such as FRP; natural and synthetic materials such as wood and fiber materials (paper, cloth, etc.) and processed products thereof Is mentioned. As the substrate, either an opaque substrate or a transparent substrate can be used. A light-colored base coat layer is preferably formed on the base material directly or via a base coat, and a luminous coat layer, an interference clear coat layer, and then a top clear coat layer are formed. Is a car body and parts,
It is preferable that the base material is previously subjected to a base treatment or a base coat by undercoating such as degreasing, chemical conversion treatment, electrodeposition coating or various types of primer coating.

Formation of Luminescent Coating Layer The luminous coating layer used in the method of forming a luminous coating film of the present invention comprises:
Preferably, it is a coating layer formed of a luminous paint containing a luminous pigment and a vehicle on the light-colored base coat layer. The vehicle contained in the luminous paint is
A phosphorescent pigment is dispersed therein, and is composed of a resin for forming a coating film and, if necessary, a crosslinking agent. Examples of the coating film forming resin constituting the vehicle include (a)
Acrylic resin, (b) polyester resin, (c) alkyd resin, (d) fluororesin, (e) epoxy resin,
Examples thereof include (f) a polyurethane resin and (g) a polyether resin, and these can be used alone or in combination of two or more. In particular, acrylic resins and polyester resins are preferably used.

As the acrylic resin (a), there can be mentioned a copolymer of an acrylic monomer and another ethylenically unsaturated monomer. Acrylic monomers that can be used in this copolymer include acrylic acid or methacrylic acid methyl, ethyl, propyl, n-butyl, i-butyl, t-butyl, 2-ethylhexyl, lauryl, phenyl, benzyl, 2-hydroxy Esterified products such as ethyl and 2-hydroxypropyl, ring-opened adducts of caprolactone of 2-hydroxyethyl methacrylate, glycidyl acrylate, glycidyl methacrylate, acrylamide, methacrylamide and N-methylolacrylamide, and polyhydric alcohol ( (Meth) acrylic acid esters. Other ethylenically unsaturated monomers copolymerizable therewith include styrene, α-methylstyrene, itaconic acid, maleic acid, vinyl acetate and the like.

Examples of the polyester resin (b) include saturated polyester resins and unsaturated polyester resins. Examples thereof include condensates obtained by heating and condensing a polybasic acid and a polyhydric alcohol. Examples of the polybasic acid include saturated polybasic acids such as phthalic anhydride, terephthalic acid and succinic acid, and unsaturated polybasic acids such as maleic acid, maleic anhydride and fumaric acid. Examples of the polyhydric alcohol include dihydric alcohols such as ethylene glycol and diethylene glycol, and trihydric alcohols such as glycerin and trimethylolpropane.

[0012] The resin for forming a coating film includes a curable type and a lacquer type, and usually, a curable type is used. In the case of a type having curability, it is used as a mixture with a crosslinking agent such as an amino resin, a (block) polyisocyanate compound, an amine-based, a polyamide-based, or a polyvalent carboxylic acid, and the curing reaction proceeds at heating or at room temperature. be able to. Further, a lacquer type coating film forming resin having no curability can be used in combination with a type having curability.

When the vehicle contains a cross-linking agent, the ratio of the resin for forming the film to the cross-linking agent is 90 to 50% by weight and the content of the cross-linking agent is 10 to 50% by weight in terms of solid content. Preferably, the coating film forming resin is 85 to 60% by weight, and the crosslinking agent is 15 to 40% by weight. If the crosslinking agent is less than 10% by weight (the resin for forming a coating film exceeds 90% by weight), the crosslinking in the coating film is not sufficient. On the other hand, when the cross-linking agent exceeds 50% by weight (the resin for forming a coating film is 50% by weight)
), The storage stability of the luminous paint is reduced and the curing speed is increased, so that the appearance of the coating film is deteriorated.

The luminous pigment contained in the luminous coating layer in the luminous coating film forming method of the present invention is a compound represented by M.Al ₂ O ₄ (where M is at least Ca, Sr, Ba)
), And the use of an activator can enhance the luminous effect. Specifically, the phosphorescent pigment is at least one of CaAl ₂ O ₄ , SrAl ₂ O ₄ , and BaAl ₂ O ₄ . Examples of the activator include europium (Eu), despronium (Dy) and the like. For example, each of Eu and Dy is 0.5 mol based on the host crystal.
It is contained to a degree.

The above luminous pigment has an emission spectrum (emission peak wavelength of 520) which is close to the spectrum of human luminosity.
nm), exhibiting a broad excitation spectrum (emission peak wavelength of about 365 nm) having high excitation efficiency even for ultraviolet rays in a short wavelength region, and having excellent basic performance as a luminous pigment, and having an afterglow luminance of It is about 5 times smaller than ZnS: Cu (about 0.4 cd / m ² ) which has been widely used in the past.
It is as high as 10 to 10 times or more (about 2 cd / m ² ), and the attenuation of the afterglow time is moderate. This is the conventional Zn
S: about 3 to about 5 to 10 times or more compared to about 200 minutes of Cu
Excellent performance of 0 hours or more. Here, the afterglow time refers to the time during which the afterglow luminance attenuates to 0.3 mcd / m ² after irradiating with an illuminance of 1000 lux for 5 minutes using a common light source D65. Light source D65
After irradiation for 5 minutes at an illuminance of 1000 lux using
It refers to the afterglow luminance after a lapse of one minute.

The luminous pigment is in the form of particles, and the average particle diameter of the raw material is 50 to 60 μm. The particles are preferably pulverized and dispersed by a sand grind mill or the like to have an average particle diameter of 5 to 25 μm. When the average particle size of the luminous pigment is less than 5 μm, there arises a disadvantage that the natural light emission property and the light emission reflection property are reduced, while the average particle diameter is 2 μm.
Even if the thickness exceeds 5 μm, the above-described disadvantage occurs.

The method for producing a luminous pigment is described in the above M.
Al_TwoO_FourSrAl where M is Sr _TwoO_FourIn the case of raw materials
SrCO as powder_Three(Purity 99.2%), Al_TwoO_Three
(Purity 99.9%) and a predetermined amount of flux
Activators such as are added and mixed, and at a high temperature of 1200 ° C. or more,
It is synthesized by firing for 3 hours in a reducing atmosphere.
As the luminous pigment, for example, "N Luminescent Luminova"
(Manufactured by Nemoto Special Chemical Co., Ltd.) can be used.

The content (PWC) of the luminous pigment in the luminous paint is preferably 1% to 60%, and more preferably 5% to 40%.
% Is more preferred. If it is less than 1%, sufficient luminous properties may not be obtained, and if it exceeds 60%, the appearance of the coating film may be deteriorated.

In addition to the above-mentioned components, the above-mentioned luminous paint comprises a polyamide wax as a lubricating dispersion of an aliphatic amide, a polyethylene wax as a colloidal dispersion mainly composed of polyethylene oxide, an anti-settling agent, a curing catalyst, an ultraviolet ray. Absorbents, antioxidants, leveling agents, surface conditioners such as silicone and organic polymers, anti-sagging agents, thickeners, defoamers, lubricants, cross-linkable polymer particles (microgels), etc. can do. These additives are usually, for example, based on 100 parts by weight (based on solid content) of the vehicle, for example,
By blending each in a proportion of 15 parts by weight or less,
The performance of paints and coatings can be improved.

The above-mentioned luminous paint is usually provided in a form in which the above components are dissolved or dispersed in a solvent. Any solvent may be used as long as it dissolves or disperses the vehicle, and an organic solvent and / or water may be used. Examples of the organic solvent include those commonly used in the field of coatings. Examples thereof include hydrocarbons such as toluene and xylene, ketones such as acetone and methyl ether ketone, esters such as ethyl acetate, cellosolve acetate, and butyl cellosolve, and alcohols. When the use of an organic solvent is regulated from the viewpoint of the environment, it is preferable to use water. In this case, an appropriate amount of a hydrophilic organic solvent may be contained. The luminous paint may be of a solvent type or a powder type. When the luminous paint is a solvent paint, a one-pack paint may be used, or a two-pack resin such as a two-pack urethane paint may be used. The dispersion of each of the above components can be carried out by using an apparatus such as a paint shaker, a ball mill, a sand grind mill, and a kneader which are usually used for producing a paint.

Interference Clear Coat Layer In the method for forming a luminous coating film of the present invention, after forming the luminous coat layer, an interference clear coat layer containing an interference pigment is formed. It is a coating layer formed by an interference paint containing a reactive pigment and a vehicle.

As the vehicle contained in the interference paint, those used in the luminous paint can be used. As the interference pigment, at least one pigment selected from mica pigments, alumina flake pigments, silica flake pigments, titanium flake pigments, and hologram pigments, preferably mica pigments, is used. As such a mica pigment, a pearl mica pigment obtained by coating a surface of natural muscovite or synthetic mica with a thin film of titanium oxide, iron oxide, or a metal oxide such as chromium, cobalt, tin, and zirconium to impart a coloring effect. Having a particle size range of 1 to 60.
μm, preferably 1 to 40 μm, and an average particle size of 15 to 25.
μm scaly particles can be mentioned. The interference color of the mica pigment can be adjusted by changing the type and amount (coating thickness) of the metal oxide to be coated. The content (PWC) of the interference pigment in the interference coating is preferably 0.1 to 30%, more preferably 0.5 to 15%.
contains. When the amount is less than 0.1%, the color flop effect when the object is viewed in the daytime or in a bright condition may not be sufficiently obtained, and when it exceeds 30%, the appearance of the coating film may be deteriorated.

The above-mentioned interference paint can contain the following coloring pigments. Examples of the organic coloring pigment include, for example, azo lake pigments, phthalocyanine pigments, indigo pigments, perylene pigments, quinophthalone pigments, dioxazine pigments, quinacridone pigments, isoindolinone pigments, metal complex pigments, and the like. Examples of the inorganic color pigment include, for example, graphite, yellow iron oxide, red iron oxide, titanium dioxide, and carbon black. When the phosphorescent pigment and / or the coloring pigment is contained, the amount of addition may include an amount that does not impair transparency. Various extenders such as calcium carbonate, barium sulfate, clay, and talc can be used in combination. The interference clear coat layer may be formed from a solvent type paint or a powder type paint. As the solvent type paint, a one-pack type paint may be used, or a two-pack type resin such as a two-pack type urethane resin paint may be used. The vehicle and other components are the same as those used in the above-mentioned luminous paint.

Formation of Top Clear Coat Layer In the above-described method for forming a luminous coating film, after forming the luminous coat layer, a top clear coat layer is formed thereon. In this case, the top clear coat layer is a layer that does not cover the lower coating layer. By forming the top clear coat layer on the luminous coat layer, it is possible to improve gloss and prevent interference pigment from projecting. As the top clear coat layer, a colorless and transparent clear coating film can be used, and further, a so-called turbid clear coating film imparting a translucency may be used. As the top clear coating, those generally used for top coating can be used, and the vehicle of the above-mentioned luminous coating can be used. When used as a top clear coat layer, a clear paint containing a carboxyl group-containing polymer and an epoxy group-containing polymer described in Japanese Patent Publication No. Hei 8-19315 is coated with a phosphorescent coating by acid rain resistance and a wet-on-wet method. It is preferably used from the viewpoint of not disturbing the orientation of the luminous pigment when coating the layer. In addition, these top clear paints, if necessary, as long as the transparency is not impaired, such as the above color pigments, extenders, modifiers, ultraviolet absorbers, leveling agents, dispersants, defoamers, etc. It is possible to incorporate additives. Further, the top clear coat layer may be formed from a solvent type paint or a powder type paint. As the solvent type paint, a one-pack type paint may be used, or a two-pack type resin such as a two-pack type urethane resin paint may be used. The vehicle and other components are the same as those used in the above-mentioned luminous paint.

Formation of Pale Base Coat Layer The pale base coat layer preferably used in the method for forming a luminous coating film is formed as a lower coating film of the luminous coating layer. By forming the light-colored base coat layer, the saturation of the interference color in the color flop effect can be increased. The light base coat layer contains a color pigment, and the lightness of the light base coat layer is
It is preferable that the brightness of the Munsell display system be equal to or higher than N6. The light-colored base coat layer can be formed by a solvent type paint or a powder type paint. As the solvent type paint, a one-pack type paint may be used, or a two-pack type resin such as a two-pack type urethane resin paint may be used. The vehicle and other components are the same as those used in the above-mentioned luminous paint.

Coating Film Forming Procedure In the method for forming a luminous coating film of the present invention, a multilayer coating film is formed by the following procedure. A light base coat layer is preferably formed on the base material. When the light-colored base coat layer is formed, its thickness is preferably 20 to 50 μm, and if it is outside this range, the appearance of the coating film may be insufficient. More preferably, it is 25 to 35 μm. In this case, a wet-on-wet (W / W
The luminous coat layer can be formed by a W) method or a wet-on-dry (W / D) method. The above W
The / W method is a method in which a base coat is applied, then dried by air drying or the like, and applied to an uncured or semi-cured base coat, whereas the W / D method is a base coat. Is applied to an undercoat film cured by baking. The thickness of the light-storing coat layer is preferably 5 to 40 μm, and if it is less than 5 μm, the light-storing property may be insufficient, and if it exceeds 40 μm, the appearance of the coating film may be poor. More preferably 2
0 to 30 μm. After the formation of the luminous coating layer, an interference clear coat layer is formed on the luminous coating layer by the W / W method or the W / D method. The thickness of the interference clear coat layer is preferably 5 to 25 μm, and if it is less than 5 μm, the color flop effect cannot be sufficiently exhibited, and if it exceeds 25 μm, the appearance of the coating film may be insufficient. More preferably, it is 15 to 20 μm. On the interference clear coat layer thus formed, at least one layer is formed as a top clear coat layer. When the interference clear coat layer contains a large amount of interference pigment or an interference pigment having a large particle size, the top clear coat layer may be
Forming more than one layer can improve the color flop effect on the surface. When two or more top clear coat layers are formed, the outermost layer may be formed as a top clear coat layer by a clear coating containing the carboxyl group-containing polymer and the epoxy group-containing polymer.
Preferred for the same reasons as above.

The formation of the top clear coat layer can be carried out after the interference clear coat layer is cured, but the W / W method is carried out on the uncured or semi-cured interference clear coat layer. Can also be used. When the top clear coat layer is formed a plurality of times, baking may be performed at the same time after forming the final clear coat layer, and it is not necessary to completely cure at the stage when the clear coat layer is initially formed. The thickness of the top clear coat layer is preferably from 20 to 50 μm. If the thickness is outside this range, the appearance of the coating film may be insufficient. More preferably, it is 25 to 35 μm.

The method of forming each coating layer is not particularly limited, but a spray method, a roll coater method, etc., and a powder coating is preferably applied by electrostatic coating, and may be applied a plurality of times. The baking is performed at a temperature of 80 to 160 ° C. for a predetermined time to obtain a coating film.

Second Method for Forming a Luminescent Coating Film The second method for forming a luminous coating film of the present invention forms a transparent base material coating film. If the substrate is transparent,
A coating film can be formed so that the interference clear coat layer and the phosphorescent coat layer can be observed from the substrate side. in this case,
As shown in FIG. 2, after forming an interference clear coat layer (14) containing an interference pigment on a transparent substrate (16), a phosphorescent coat layer containing a luminous pigment is formed on the interference clear coat layer. (13) is formed. Preferably, the light-colored base coat layer (12) is formed after forming the phosphorescent coat layer (13). Because the base material is transparent, after forming an interference clear coat layer containing an interference pigment on the base material surface opposite to the side viewing the base material, forming a luminous coat layer containing a luminous pigment, so-called This is a painting method called a back coat. Examples of the base material having transparency include inorganic materials such as glass in the above base materials; and various plastic materials. In this case, since the interference clear coat layer has a transparent substrate side on the viewing side and does not cause the interference pigment to protrude, even an interference pigment having a large particle diameter can be used without any problem of protrusion from the coating film. In addition, since the transparent substrate also has a function of protecting the coating film, the durability of the coating film is improved.
In the second coating film forming method, it is not necessary to form the top clear coat layer. The interference clear coat layer and the phosphorescent coat layer are the same as those in the method for forming a coating film according to the first invention. The thickness of each phosphorescent coating layer and color base coating layer is the same as described above.

Luminescent coating The luminous coating obtained by the first coating film forming method of the present invention comprises a luminous coating layer, an interference clear coating layer, and then a top clear coating layer formed on a substrate. I have. Preferably, a light-colored base coat layer is formed before forming the phosphorescent coat layer.

The luminous coating product obtained by the second coating film forming method of the present invention has an interference clear coat layer and a luminous coating layer formed on a transparent substrate. Preferably, a light-colored base coat layer is formed after the formation of the phosphorescent coat layer.

The luminous paint of the present invention has a multi-layer paint film formed by the above-described luminous paint film forming method, and is used for an automobile body such as an automobile body, an automobile bumper and the like, and a vehicle outer panel and a component such as a motorcycle. , Container outer surface, coil-coated building materials, home appliances, communication-related electrical equipment, etc., doorway panels, staircase rims, switchboards, handrails, handles, keyholes, switches, induction signs, guide rails, emergency equipment, Painted on evacuation equipment.

[0033]

EXAMPLES Next, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples. In addition, the compounding amount represents a weight part unless there is particular notice.

Examples 1 to 18 and Comparative Example 1 Preparation of luminous paint Acrylic resin (styrene / methyl methacrylate / ethyl methacrylate / hydroxyethyl methacrylate /
Methacrylic acid copolymer, number average molecular weight about 20,000,
A hydroxyl value of 45, an acid value of 15, and a solid content of 50% by weight, and a melamine resin (trade name, “Uban 20SE”, manufactured by Mitsui Chemicals, Inc., solid content of 60% by weight) are blended at a solids weight ratio of 80:20. The following luminous pigments and fluorescent pigments in Comparative Examples were blended in the proportions shown in Table 1 with respect to the vehicle thus obtained.
Next, an organic solvent (toluene / xylene / ethyl acetate /
(Butyl acetate = 70/15/10/5) by stirring with a stirrer so as to obtain an appropriate coating viscosity to prepare a luminous paint. _{1: SrAl 2 O 4 2:} CaAl 2 O 4 3: BaAl 2 O 4 4: SrAl 2 O 4, (- Eu-Dy (Eu: 0.5mo
1, Dy: 0.5 mol) as an activator) 5: Fluorescent pigment (calcium sulfide / bismuth: for comparative example)

Preparation of Substrate A dull steel plate (length 300 mm, width 100 mm and thickness 0.8 mm) was treated with a zinc phosphate treating agent ("Surfdyne SD2").
000 "(manufactured by Nippon Paint Co., Ltd.), and then a cationic electrodeposition paint (" Power Top U-50 ", manufactured by Nippon Paint Co., Ltd.) was electrodeposited so as to have a dry film thickness of 25 [mu] m. Then, after baking at 160 ° C. for 30 minutes, the intermediate coating (“Olga S-90 Sealer Gray (N-
8) ", manufactured by Nippon Paint Co., Ltd.) was applied by air spraying so as to have a dry film thickness of 30 μm, and baked at 140 ° C. for 30 minutes to form a pale base coat. However, in Examples 1 to 3, the intermediate coating ("Olga S-90 Sealer Gray (N-8)", manufactured by Nippon Paint Co., Ltd.) was omitted.

After a member molded from a polypropylene resin for an automobile bumper is degreased with isopropyl alcohol, the following bumper primer (“RB”, manufactured by Nippon Bee Chemical Co., Ltd.) is applied by air spraying, and then at 140 ° C. for 20 minutes. After baking so as to have a dry film thickness of 30 μm, an intermediate coating (“Olga S-90 Sealer Gray (N-8)”,
(Nippon Paint Co., Ltd.) was applied by air spraying so as to have a dry film thickness of 30 μm, and baked at 140 ° C. for 30 minutes to form a pale base coat.

Method for forming a coating film The above-mentioned substrate was coated with the luminous paint obtained above in a dry film thickness of 25 μm.
To form a phosphorescent coating layer. Coating was performed using an electrostatic coating machine (“Auto REA”, manufactured by ABB Industries) at an atomization pressure of 2.8 kg / cm ² . Atmosphere of the booth during painting is temperature 25 ℃, humidity 75%
Held. Bake at 140 ° C. for 30 minutes. After that, the interference paint A (interference mica pigment-containing acrylic melamine resin-based clear paint) or the interference paint B (titanium oxide-coated silica flake pigment-containing acrylic melamine resin-based clear paint) is sprayed with air to a dry film thickness of 15 μm. After painting, interference clear coat, setting for 3 minutes after painting, dry paint with dry film thickness of 35 μm
Paint, set at room temperature for 10 minutes,
Bake at 140 ° C. for 30 minutes. The luminous property and the color flop effect of the obtained coating film were evaluated by the following evaluation methods. Table 1 shows the results. The clear paint used was an acrylic / melamine resin-based clear paint 1 (trade name: "Super Lac O-130 Clear", manufactured by Nippon Paint Co., Ltd.) or a clear paint containing a carboxyl group-containing polymer and an epoxy group-containing polymer. Paint 2 ("Macflow O-520 Clear", manufactured by Nippon Paint Co., Ltd.)
There are two types. Table 1 shows the evaluation results.

[0038]

[Table 1]

Examples 19 to 23 and Comparative Example 2 Method for coating transparent substrate (back coating method) A transparent and colorless acrylic plate (length 300 mm, width 100 mm)
And a plate having a thickness of 5 mm) were degreased to obtain a substrate C. After forming an interference clear coat layer on the base material C with the interference coating material A so as to have a dry film thickness of 15 μm, a luminous coat layer was formed so as to have a dry film thickness of 25 μm.
For Examples 19 to 23 and Comparative Example 2, furthermore, an intermediate coating ("Olga S-90 Sealer Gray (N-8)",
(Nippon Paint Co., Ltd.) was applied by air spraying so as to have a dry film thickness of 30 μm, and baked at 140 ° C. for 30 minutes to form a pale base coat. The luminous property and the color flop effect of the obtained coating film were evaluated by the following evaluation methods.
The results are shown in Table 1.

Evaluation method (luminous property) Each of the coating films obtained above was subjected to JISZ9100
(Luminescent safety signboard) After storing for 3 hours in a dark place with the outside light blocked by 8.3, irradiate the light of a fluorescent lamp with a brightness of 200 lux for 30 minutes, stop irradiation, and after 60 minutes Of each coating film was visually evaluated. 4: There is a feeling that light is sufficiently emitted 3: There is a feeling that light is emitted 2: Weak but light is emitted and recognition is possible 1: No light is emitted (color flop effect) after formation The color of the coating film was visually evaluated when the coating film was viewed from almost right above (A) and when the coating film was viewed at a bird's-eye angle of about 15 degrees with respect to the test piece (B). 4... The colors presented in (A) and (B) are clearly different from each other, are recognized as interference coating films, and have a higher saturation of interference colors. 3... The colors presented in (A) and (B), respectively. Is clearly different, and is recognized as an interference coating film 2... (A) and (B) each exhibit a different color and is at a level recognized as an interference coating film 1... (A) and (B) Are the same color and are not recognized as interference coatings

[0041]

[Table 2]

As is evident from the results in Tables 1 and 2, Examples 1 to 23 are films in which a luminous film was formed by the method of forming a luminous film of the present invention, and the luminous property was not good at night or the like. Good, visibility was improved, and a coated article exhibiting a color flop effect of an interference clear coat layer containing an interference pigment was obtained in a situation such as daytime. On the other hand, in Comparative Examples 1 and 2, the use of the fluorescent pigment resulted in poor light storage properties.

[0043]

As described above, according to the present invention, after forming a luminous coating layer containing a luminous pigment on a substrate, an interference clear coating layer containing an interference pigment is formed, and then a top clear coating layer is formed. And a method for forming a luminous coating film comprising: forming an interference clear coat layer containing an interference pigment on a transparent substrate; and then forming a luminous coating layer containing the luminous pigment. In the phosphorescent coating obtained by these methods, the coating automatically emits light at night or in a darkened state, so that the visibility is improved. Also, once light is absorbed, it emits light for a long time, making it easy to see the luminous paint applied to the substrate, and in the daytime or in bright conditions, the color flop effect of the interference clear coat layer containing the interference pigment is improved. Can be expressed. Examples of specific uses include automobile bodies, automobile parts such as automobile bumpers, vehicle outer panels and parts such as motorcycles, container outer surfaces, coil-coated building materials, home appliances, communication-related electrical equipment, and doorway panels, Painted on staircase edges, switchboards, handrails, handles, keyholes, switches, guidance signs, guide rails, emergency equipment, evacuation equipment, etc.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a multilayer coating film formed by a first coating film forming method of the present invention.

FIG. 2 is a cross-sectional view of a multilayer coating film formed by a second coating film forming method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Base material 12 Pale base coat layer 13 Luminescent coat layer 14 Interference coat layer 15 Top clear coat layer 16 Transparent base material

Claims (7)

[Claims] 1. A luminous coating layer containing a luminous pigment is formed on a substrate, and then an interference clear coating layer containing an interference pigment is formed on the luminous coating layer, and a top clear layer is further formed thereon. A method for forming a luminous coating film for forming a coating layer. 2. The method for forming a luminous coating film according to claim 1, wherein a light-colored base coat layer is formed before the luminous coating layer is formed. 3. A luminous coating film comprising: forming an interference clear coat layer containing an interference pigment on a transparent substrate; and forming a luminescence coating layer containing a luminous pigment on the interference clear coat layer. Forming method. 4. The method for forming a luminous coating film according to claim 3, wherein a light-colored base coat layer is formed after the formation of the luminous coating layer. 5. The luminous pigment according to claim 1, wherein the luminous pigment is a compound represented by M.Al ₂ O ₄ (wherein M is at least one of Ca, Sr and Ba). 2. The method for forming a photoluminescent film according to claim 1. 6. The light according to claim 1, wherein the interference pigment is at least one pigment selected from mica pigment, alumina flake pigment, silica flake pigment, titanium flake pigment, and hologram pigment. Method for forming a functional coating film. 7. A luminous coating product obtained by the method of forming a luminous coating film according to any one of claims 1 to 6.