JPH1135856A - Coating material containing photoluminescent pigment and formation of complex coated film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition having a photoluminescent feeling superior than usual within a high lightness and saturation color region, and further an excellent flip-flop property, and suitable as an automotive top coating material by containing colored aluminum, etc., as a photoluminescent pigment. SOLUTION: This coating material contains (A) colored aluminum and (B) alumina flakes, and preferably further (C) crosslinkable resin particles, as a photoluminescent pigment. Preferably, the photoluminescent pigment comprises, for instance, a colored pigment chemically adsorbed on the surface of a scaly aluminum pigment through a specific thermally polymerizable carboxylic acid, etc., as the component A and aluminum oxide covered with a metal oxide such as titanium dioxide as the component B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a glitter pigment-containing coating composition containing colored aluminum and alumina flake, which can be suitably used as a thermosetting paint, especially a top coating for automobiles, and a glitter pigment-containing coating composition. TECHNICAL FIELD The present invention relates to a method for forming a composite coating film using the same and an article having the composite coating film.

[0002]

2. Description of the Related Art As a top coating for automobiles, a coating containing a brilliant pigment called a metallic paint containing a brilliant pigment such as metal powder and / or mica is generally known. Among such brilliant pigments, a metallic paint containing aluminum powder or mica powder coated with a metal oxide changes the amount of reflected light depending on the viewing angle (hereinafter referred to as “flip-flop property”) and has high design properties. doing.

[0003] However, improving the flip-flop property leads to improvement in glitter at the highlight position.
When viewed from the shade position, it looks blackish, which leads to a reduction in glitter at the shade position. On the other hand, in order to improve the blackness from the shade position (to increase the lightness), if a color sensation is imparted, the brilliantness and the saturation will be reduced, and in a color region where the lightness and saturation are high. The paint color design for the purpose of improving the flip-flop property has been limited.

[0004]

SUMMARY OF THE INVENTION The present invention has an unprecedented brilliant feeling in a color region having a high lightness and a high saturation, has a high flip-flop property, and is viewed from a shade position. Even in such a case, it is an object of the present invention to form a composite coating film having high designability while maintaining high brightness and saturation as seen from the position of highlight.

[0005]

Means for Solving the Problems The inventors of the present invention have made a glittering pigment-containing coating composition containing colored aluminum and alumina flakes into a composite coating film by a two-coat one-bake process. Clarified that the above problems could be solved.

That is, the present invention provides [1] a glitter pigment-containing coating composition containing colored aluminum and alumina flake as the glitter pigment. [2] In a method of forming a composite coating film on an undercoated base material in two coats and one bake, the first layer is formed from the bright pigment-containing coating composition according to claim 1, and the second layer is cleared. The method for forming a composite coating film according to claim 1, wherein the coating film is formed. [3] a composite coating film formed by the above method. And [4] an article having the composite coating film. Is provided.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The colored aluminum pigment used in the bright pigment-containing coating composition of the present invention is not particularly limited as long as a resin film containing the colored pigment is formed on the surface of the aluminum pigment. For example, Japanese Unexamined Patent Publication No.
The scaly colored aluminum pigments in the colored metallic pigments described in JP-A-70 can be suitably used.

That is, (1) a color pigment is chemically adsorbed on the surface of a flaky aluminum pigment via a thermally polymerized carboxylic acid having at least one double bond and at least two carboxyl groups in the same molecule. And (2) a resin obtained by polymerizing a radical polymerizable unsaturated carboxylic acid and a monomer having three or more radical polymerizable double bonds. And the like.

Examples of the thermally polymerized carboxylic acid include, for example, a thermally polymerized carboxylic acid obtained by thermally polymerizing linseed oil fatty acid or soybean oil fatty acid, and a thermally polymerized carboxylic acid obtained by thermally polymerizing linseed oil fatty acid or soybean oil fatty acid and acrylic acid. Are used. The amount of the thermally polymerized carboxylic acid varies depending on the surface area of the aluminum pigment used and the amount of the coloring pigment used, but 0.2 to 15 parts by weight, particularly 1 to 7 parts by weight, per 100 parts by weight of the aluminum pigment of 1 m 2 / g. Parts by weight are preferred.

Specifically, for example, an aluminum pigment and a color pigment are mixed and dispersed in a solution obtained by dissolving the above-mentioned thermally polymerized carboxylic acid or resin in an organic solvent in a volatile solvent, and this mixture is spray-dried to obtain an aluminum pigment. Forming a resin film containing a coloring pigment on the surface of the above, or in a solvent in which a monomer having a double bond is soluble and in which the resin obtained by polymerizing this monomer becomes insoluble, the above monomer, aluminum pigment and coloring After adding and mixing the pigment, a polymerization initiator is added thereto, and the monomer is polymerized to form a resin layer containing a color pigment on the surface of the aluminum pigment.

The coloring pigment for coloring the aluminum pigment may be any of an organic pigment and an inorganic pigment as long as it does not dissolve in the organic solvent used in the production.
There is no particular limitation.

The colored aluminum used in the present invention is:
A scaly surface having a smooth surface and less irregular reflection is desirable. The particle size varies depending on the use of the colored aluminum pigment, but the average particle size is 1 to 100 μm, preferably 2 to 60 μm.
m, average thickness 0.1-5 μm, preferably 0.2-40
μm can be used.

The aluminum pigment to which a fatty acid such as oleic acid or stearic acid is added at the time of pulverization has a feature that each aluminum particle is coated with the fatty acid and the surface is not oxidized.
Furthermore, it is preferable because the thermally polymerized carboxylic acid and the fatty acid used at the time of grinding are substituted and chemically adsorbed to aluminum.

The colored aluminum used in the present invention can be colored to any color and is excellent in metallic glitter. Further, a colored aluminum (2) obtained by coating the colored aluminum of the above (1) with a polymer comprising a monomer having three or more radically polymerizable unsaturated carboxylic acids and radically polymerizable double bonds is further coated with a top coating composition for an automobile. When used for a product, it is particularly suitable because it has excellent water resistance and chemical resistance as well as design properties.

More specifically, a friend color series such as "Friend Color F500 (trade name)" sold by Showa Aluminum Powder Co., Ltd., or "Palio" sold by BASF Corporation (BASF). "Chrome Gold L-2020 (trade name)" is particularly excellent in metallic brilliant color.

The content (PWC%) of the above colored aluminum in the coating composition containing a glittering pigment is 0.01% to 0.01%.
15.0%, and if it exceeds the upper limit, the appearance of the coating film is reduced,
If the ratio is below the lower limit, the coloration and the glitter will be reduced. Preferably, it is 0.1% to 14.0%, more preferably,
1% to 13.0%.

The alumina flake used in the glitter pigment-containing coating composition of the present invention is not particularly limited. For example, a flaky acid value aluminum pigment described in JP-A-9-77512 can be suitably used.

That is, aluminum oxide (Al 2 O 3)
Is coated with a metal oxide such as titanium dioxide,
The average particle size is 3 to 60 μm, preferably 5 to 30 μm, and the thickness is 0.1 to 0.8 μm, preferably 0.2 to 0.4 μm.
m. Further, since the surface smoothness is high and the particle size distribution is sharp, scattering by fine particles is small.

Further, when the aspect ratio (particle diameter / thickness) is 2
Since the surface of the flaky acid value aluminum of 0 or more is coated with a metal oxide, it becomes a pigment having a pearly (pearl luster). When it is formed into a coating film, the conventional mica is used from both the highlight and shade positions. A coating film having a strong shine, which cannot be obtained with powder, is obtained. The appearance is transparent, and a three-dimensional impression can be expressed.

As the above alumina flake, for example, “S” sold by Merck Japan Ltd.
SDA series such as "DA-SILVER W-3 (trade name)".

These are metal oxides (Al 2 O 3, TiO 2)
(2, SnO2, ZrO2, Fe2O3, etc.) by changing the seed and amount, it is possible to cover from silver color to copper color and sienna interference color, and by using the composite coating forming method of the present invention, higher brightness can be obtained. When exposed to strong light such as sunlight, a coating film having a paint color having a particularly strong glitter can be provided.

The content (PWC%) of the alumina flake in the bright pigment-containing coating composition is 0.01% to 1%.
When the content exceeds the upper limit, the appearance of the coating film is reduced, and when the content is less than the lower limit, the glitter is reduced. Preferably, 0.1%
~ 14.0%, more preferably 1% ~ 13.0%.
%.

The colored aluminum and alumina flakes used in the glitter pigment-containing coating composition of the present invention can exert their effects when used in combination with each other. In addition, by combining the glittering pigment-containing coating layer using the above-mentioned colored aluminum and alumina flake pigment together with a clear coating layer to form a composite coating film, a composite having an unprecedented novel design property A coating can be obtained.

The total content (PWC%) of the colored aluminum and alumina flakes used in the glitter pigment-containing coating composition of the present invention is from 0.01% to 20.0%. If the value falls below the lower limit, the brilliant feeling decreases. Preferably, it is 0.1% to 17.0%,
More preferably, it is 1% to 14.0%.

Also, in the glitter pigment-containing coating composition of the present invention, it is possible to enhance the glitter by setting the content ratio of alumina flakes to be high, so that the conventional mica can be used from both the highlight and shade positions. It is possible to provide a coating film having a strong shine and transparency that could not be obtained with powder. Further, by using colored aluminum in combination, it is possible to obtain a coating film having a novel design property of giving a high color sense even when viewed from the shade position.

Depending on the coating color, other glittering pigments can be used in combination. Other glitter pigments that can be used in combination
Aluminum powder or mica powder coated with a metal oxide such as titanium dioxide or iron oxide is generally used, but other flat pigments having glitter may also be used. In addition, organic
An inorganic coloring pigment or extender can be used in combination.

When such other pigments are used in combination, the total pigment concentration (PWC%) in the paint is 0.1 to 0.1%.
80%, preferably 0.5% to 70%,
More preferably, it is 1.0% to 60%. If it exceeds the upper limit, the appearance of the coating film will be reduced.

[0028] The coating composition of the present invention contains a thermosetting film-forming resin. This resin disperses a glitter pigment, other pigments and additives to form a cured coating film, and is not particularly limited. Generally, a thermosetting film-forming resin having at least one hydroxyl group selected from the group consisting of an acrylic resin, a polyester resin, an alkyd resin, an epoxy resin and the like can be used, and these may be an amino resin and / or a blocked isocyanate resin. Used in combination with the curing agent. It is preferable to combine an acrylic resin having a hydroxyl group with an amino resin from the viewpoints of weather resistance, pigment dispersibility and coating workability.

The weight composition ratio of the thermosetting film-forming resin and the curing agent in the glitter pigment-containing coating composition of the present invention is 90.
/ 10 to 10/90, preferably 80/20 to 5
0/50. If it exceeds the upper limit, the curability will decrease, and if it falls below the lower limit, the coating will be hard and brittle.

The glitter pigment-containing coating composition of the present invention may contain a viscosity controlling agent. The viscosity controlling agent is used for forming a good and uniform coating film. As the viscosity controlling agent, those having a thixotropic property can be generally used as an "anti-sagging agent". Examples of such a type include a polyamide type, a polyethylene type, and an organic bentonite type. In addition, non-crosslinked or crosslinked resins or particles utilizing the interaction of a polar group can be mentioned as the viscosity controlling agent. .

In the present invention, the viscosity controlling agent may be used alone, but may be used in combination. However, those which do not affect gloss and color development when formed into a coating film are preferable, and among the above-mentioned viscosity control agents, crosslinkable resin particles are particularly preferable.

As such crosslinkable resin particles, those described in, for example, JP-A-58-129066 are preferable, and are insoluble in the organic solvent used in the coating composition of the present invention and have an average particle size of 0.02. A crosslinkable resin particle of about 0.5 μm is preferred. If the upper limit is exceeded, the stability will decrease.

The above-mentioned crosslinkable resin particles are prepared by mixing a monomer having a zwitterionic group in the molecule as one of the polyhydric alcohol components, and a resin having an emulsifying ability such as an alkyd resin or a polyester resin. In the presence of the agent,
Those obtained by emulsion polymerization of an ethylenically unsaturated monomer in an aqueous medium are preferred.

The monomer having the above zwitterionic group in the molecule includes -N (+)-R-COO (-) or -N (+)-
Those represented as R-SO3 (-) and having two or more hydroxyl groups can be used. As such a monomer, a hydroxyl group-containing aminosulfonic acid-type zwitterionic compound is preferable from the viewpoint of resin synthesis. Specific examples include bishydroxyethyl taurine.

The resin having an emulsifying zwitterionic group in the molecule, which is synthesized using the above monomer, has an acid value of 30 to 150 mgKOH / g, preferably 40 to 150 mgKOH / g.
It is preferable to use a polyester resin having a KOH / g and a number average molecular weight of 500 to 5,000, preferably 700 to 3,000. If the upper limit is exceeded, the handling properties of the resin will decrease,
If it is below the lower limit, a resin having an emulsifying ability is desorbed when a coating film is formed, or the solvent resistance is reduced.

In the synthesis of the crosslinkable resin particles, the ethylenically unsaturated monomer to be emulsion-polymerized is a monomer having two or more radically polymerizable ethylenically unsaturated groups in the molecule. Such a monomer having two or more radically polymerizable ethylenically unsaturated groups in the molecule is preferably contained in the range of 0.1 to 10% by weight of all the monomers. The amount is selected to provide sufficient crosslinking to dissolve the particulate polymer in the solvent.

The crosslinkable resin particles used in the brilliant pigment-containing coating composition of the present invention are generally contained in an emulsion resin, and do not contain a low-molecular emulsifier or a protective colloid which lowers the performance when formed into a coating film. And 2 in the molecule
Since the polymer is crosslinked by copolymerizing at least two monomers having a radically polymerizable ethylenically unsaturated group, the coating film is excellent in water resistance, solvent resistance, gloss and the like.

The amount of the viscosity control agent used in the glittering pigment-containing coating composition of the present invention is determined based on the resin solid content of the coating composition.
It is added in an amount of 0.01 to 15 parts by weight, preferably 0.1 to 12 parts by weight, more preferably 0.2 to 9 parts by weight based on 0 parts by weight. When the amount of the viscosity controlling agent exceeds 15 parts by weight, the appearance is deteriorated. When the amount is less than 0.01 part by weight, the effect of controlling the viscosity is not obtained, which causes compatibility between layers and inversion.

Further, in the glitter pigment-containing coating composition of the present invention, a curing catalyst, an ultraviolet absorber, an antioxidant, a surface preparation agent and the like can be used if necessary.

The coating composition containing a brilliant pigment of the present invention has a total solid content of 10 to 70% by weight, preferably 2 to 70% by weight.
0 to 50% by weight. Exceeding the upper and lower limits lowers the paint stability. At the time of application, it is 10 to 60% by weight, preferably 15 to 50% by weight. If the upper limit is exceeded, the viscosity is too high and the appearance of the coating film is reduced, and if it is lower than the lower limit, the viscosity is too low and poor appearance such as adaptability and unevenness occurs.

The method for producing the coating composition of the present invention is not particularly limited, and any method known to those skilled in the art, such as kneading and dispersing a compound such as a pigment using a kneader or a roll, can be used.

The coating composition of the present invention may be prepared from any substrate such as wood, metal, glass, cloth, plastic, foam, etc.
In particular, it can be used advantageously for plastics and metal surfaces, such as steel, aluminum, their alloys and castings, but can be used particularly preferably for cationic electrodepositable metal products.

The metal products include, for example, iron, copper,
Aluminum, tin, zinc, and the like, and alloys containing these metals are included. Specific examples include automobile bodies and parts such as passenger cars, trucks, motorcycles, and buses. It is particularly preferable that these metals have been previously subjected to a chemical conversion treatment with a phosphate, a chromate or the like.

In general, the thickness of the coating film at the time of coating with the glitter pigment-containing coating composition of the present invention varies depending on the desired use, but in many cases, 5 to 40 μm is useful, and more preferably 10 to 25 μm. It is about. If the upper limit is exceeded, problems such as unevenness or flow may occur during coating, and if the lower limit is not reached, the base material cannot be concealed and a film break occurs.

After coating on the substrate, the coating film is cured, and the cured film is cured at 100 to 180 ° C., preferably 120 to 160 ° C., to obtain a cured film having a high degree of crosslinking. When the amount exceeds the upper limit, the coating film becomes hard and brittle, and when the amount is less than the lower limit, curing is not sufficient. The curing time varies depending on the curing temperature.
Curing at 10 ° C. for 10 to 30 minutes is suitable.

The coating composition containing a brilliant pigment in the present invention is generally preferably of a solution type. If the composition is a solution type, it may be an organic solvent type, an aqueous type (water-soluble, water-dispersible, emulsion), a non-aqueous type. Any of a dispersion type may be used.

When the bright pigment-containing paint is used as an aqueous paint, US Pat. No. 5,151,125 and US Pat. No. 5,151,125 may be used as a binder for the bright pigment-containing paint composition.
183, 504 and the like can be used. In particular, US Pat.
The thermosetting film-forming resin obtained by combining the melamine resin with the acrylic resin having an acrylamide group, a hydroxyl group, and an acid group described in No. 3,504 is excellent in finish and appearance performance.

When the glitter pigment-containing coating composition of the present invention is applied to an automobile body, an electrodeposition coating film and a cured or uncured intermediate coating film are formed as undercoats on a chemically treated steel sheet. The coating is preferably performed on the base material by a coating method such as electrostatic coating or air spray. In order to suppress unevenness in glitter, it is more preferable to apply the paint in two stages than in one stage.

Further, a two-coat, one-bake coating method in which a clear paint is applied on an uncured glittering pigment-containing coating film of the present invention by wet-on-wet, and then both coating films are cured, is a point of design. Is preferred.

When the glitter pigment-containing paint is used as a water-based paint, the glitter pigment-containing coating must be coated before coating the clear paint in order to obtain a good finished coating.
It is desirable to heat at １００100 ° C. for 2 to 10 minutes.

The electrodeposition paint which is applied on the substrate used in the method for forming a composite coating film of the present invention and forms an undercoat layer includes:
Cationic and anionic types can be used, but the cationic electrodeposition coating composition gives a composite coating film having excellent corrosion resistance. Cationic electrodeposition coating composition is a cathodic deposition type thermosetting electrodeposition coating material which is based on a resin having a basic amino group and is made water-soluble by neutralizing with an acid. Painted as cathode.

As the resin having a basic amino group used in the cationic electrodeposition coating material, a secondary amine (for example, a primary amine is blocked by a ketimination of diethylene triamine or the like) to an epoxy group of a bisphenol type epoxy resin. Resins with a secondary amine) are preferred.

As the crosslinking agent, it is preferable to use a blocked polyisocyanate sealed with a blocking agent such as alcohols, phenols, oximes and lactams.

The above-mentioned cationic electrodeposition paint contains a pigment such as a color pigment, an extender pigment, a rust preventive pigment, a hydrophilic and / or hydrophobic solvent, an additive and the like as required. The amount of the pigment can be 5 to 150 parts by weight based on 100 parts by weight of the resin solids.

The electrodeposition coating film usually has a thickness of 10 after baking.
The thickness is preferably set to be about 40 μm, more preferably 15 to 25 μm. It is more preferable to perform a normal chemical conversion treatment before the electrodeposition coating.

The intermediate coating composition for forming an undercoat layer in the method for forming a composite coating film of the present invention hides underlying defects,
This is for ensuring surface smoothness and imparting chipping resistance after top coating, and is applied using an intermediate coating containing various organic and inorganic coloring pigments and extender pigments.

Examples of the color pigments for the intermediate coating include organic azo chelate pigments, insoluble azo pigments, condensed azo pigments, phthalocyanine pigments, indigo pigments, perinone pigments, perylene pigments, dioxane pigments, and quinacridone. Pigments, isoindolinone pigments, metal complex pigments, etc., inorganic yellow salts, yellow iron oxide, red iron oxide, carbon black, titanium dioxide, etc., and extender pigments such as calcium carbonate, barium sulfate, clay, talc, etc. Is used. As a standard, gray intermediate coatings with carbon black and titanium dioxide as main pigments are often used, but it is also possible to use so-called color intermediate coatings that combine various coloring pigments according to the concealment of the top coat. it can.

The thermosetting film-forming resin of the intermediate coating is not particularly limited, and a film-forming resin such as an acrylic resin, a polyester resin, an alkyd resin, an epoxy resin, or a urethane resin can be used. These are used in combination with a curing agent such as an amino resin and / or a blocked isocyanate resin. A combination of an alkyd resin and / or a polyester resin and an amino resin is preferred from the viewpoint of pigment dispersibility or workability.

The solid content in the intermediate coating composition is 30 to 7
0% by weight, preferably 35 to 55% by weight.
At the time of application, it is 10 to 60% by weight, preferably 20
５０50% by weight. The intermediate coating is preferably applied on a heat-cured or uncured electrodeposition coating film by a method such as electrostatic coating, air spray, or airless spray. , Generally 10-60
It is preferably about μm, more preferably about 20 to 50 μm. If the upper limit is exceeded, problems such as wrinkles and sagging may occur during coating. If the lower limit is not reached, the base cannot be concealed.

The intermediate coating film itself can be cured by heating at a temperature of about 100 to 180 ° C., and in the present invention, a composite coating film is formed by combining with a bright pigment-containing coating film and a clear coating film. Excellent appearance and coating film performance can be exhibited.

As the form of the intermediate coating material used in the present invention, a solution type is preferably used, and if it is a solution type, an organic solvent type, aqueous (water-soluble, water-dispersible, emulsion) or non-aqueous-dispersion type is used. Any of them. If necessary,
A curing catalyst, a surface preparation agent and the like can be used.

The clear paint used in the method for forming a composite coating film of the present invention is formed to ensure surface smoothness and to provide other properties required for the coating film, and impairs the transparency of the coating film. To a lesser extent, a coloring pigment may be included.

The thermosetting film-forming resin of the clear paint is not particularly limited.
A film-forming resin such as a polyester resin, an epoxy resin, or a urethane resin can be used, and these are used in combination with a curing agent such as an amino resin and / or a blocked isocyanate resin. In terms of transparency or acid etching resistance, etc., a combination of an acrylic resin and / or a polyester resin and an amino resin,
An acrylic resin and / or a polyester resin having an epoxy curing system may be used.

The solid content in the clear coating is from 20 to
It is 60% by weight, preferably 35 to 55% by weight. The solid content at the time of application is 10 to 50% by weight, preferably 20 to 50% by weight. The clear coating, on the uncured bright pigment-containing coating film, electrostatic coating,
It is preferable to apply by a method such as air spraying, and the dry film thickness of the formed coating film is generally preferably about 10 to 60 μm, more preferably about 20 to 50 μm. If the upper limit is exceeded, problems such as splashes or sagging may occur during coating. If the lower limit is not reached, irregularities on the base cannot be concealed.

Although the clear coating film itself can be cured by heating at a temperature of about 100 to 180 ° C., in the present invention, the clear coating film and the bright pigment-containing coating film, or the color base coating film and the bright pigment-containing coating film are coated. By forming a composite coating film by combining with the film and curing by heating, excellent appearance and coating film performance can be exhibited.

It should be noted that the clear coating preferably contains a viscosity controlling agent in order to apply the bright pigment-containing coating composition of the present invention wet-on-wet. The amount of the viscosity control agent to be added to the clear coating composition is 0.01 to 10 parts by weight, preferably 0.02 to 8 parts by weight, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the resin solid content of the coating composition. 03
It is added in an amount of up to 6 parts by weight. When the amount of the viscosity control agent is 10
If the amount is more than 0.1 parts by weight, the appearance deteriorates. If the amount is less than 0.1 part by weight, the effect of controlling the viscosity cannot be obtained, which may cause infiltration or inversion between layers.

As the coating form of the clear coating used in the method for forming a composite coating film of the present invention, a solution type is preferably used. If the solution type is a solution type, an organic solvent type or an aqueous type (water soluble,
(Aqueous dispersibility, emulsion) and non-aqueous dispersion type. If necessary, a curing catalyst, a surface preparation agent and the like can be used.

In many cases, the composite coating film containing the glitter pigment-containing coating film as at least one layer is 30 to 3
00 μm. Preferably it is 50 to 250 μm.
If it exceeds the upper limit, the physical properties of the film such as a thermal cycle decrease, and if it falls below the lower limit, the strength of the film itself decreases.

[0069]

The present invention will be described below in detail with reference to examples. Parts mean parts by weight unless otherwise specified.

Production Example Preparation of Crosslinkable Resin Particles In a reaction vessel equipped with a stirring and heating device, a thermometer, a nitrogen inlet tube, a cooling tube and a decanter, 213 parts of bishydroxyethyltaurine, 208 parts of neopentyl glycol, 296 parts of phthalic anhydride were added. , 376 parts of azelaic acid and 30 parts of xylene were charged and heated. Water generated by the reaction was removed by azeotropic distillation with xylene. The temperature of the reaction solution was set to 210 ° C. over about 3 hours from the start of reflux, and stirring and dehydration were continued until the acid value equivalent to carboxylic acid reached 135 mgKOH / g (solid content).

After the temperature of the solution was cooled to 140 ° C., 500 parts of Kajura E10 (trade name; glycidyl versatate ester manufactured by Shell Co.) was added dropwise in 30 minutes, and then the reaction was continued for about 2 hours while stirring. finished. An amphoteric ionic group-containing polyester resin having an acid value of 55 mgKOH / g, a hydroxyl value of 91 mgKOH / g, and a number average molecular weight of 1250 was obtained.

The amphoteric ion-containing polyester resin 10
Parts, 140 parts of deionized water, dimethylethanolamine 1
, 50 parts of styrene and 50 parts of ethylene glycol dimethacrylate were vigorously stirred in a stainless steel beaker to prepare a monomer suspension. Also, an aqueous initiator solution was prepared by mixing 0.5 parts of azobiscyanovaleric acid, 40 parts of deionized water and 0.32 parts of dimethylethanolamine.

A reaction vessel equipped with a stirring and heating device, a thermometer, a nitrogen inlet tube and a cooling tube was charged with 5 parts of the amphoteric group-containing polyester resin, 280 parts of deionized water and 0.5 part of dimethylethanolamine. The temperature rose.
Here, 251 parts of the monomer suspension and 40.
82 parts were simultaneously added dropwise over 60 minutes, and the reaction was further continued for 60 minutes, and then the reaction was terminated.

A crosslinkable resin particle emulsion having a particle diameter of 55 nm measured by a dynamic light scattering method was obtained. Xylene was added to this crosslinkable resin particle emulsion, water was removed by azeotropic distillation under reduced pressure, and the medium was replaced with xylene to obtain a xylene solution of crosslinkable resin particles having a solid content of 20% by weight.

Example 1 Preparation of a Bright Pigment-Containing Coating Composition A part of the thermosetting acrylic resin and the coloring pigment in the following composition were mixed in advance with a desktop disper using glass beads as a dispersing medium. It was dispersed until it became 5 μm or less to prepare a pigment paste. In addition, the crosslinkable resin particles were gradually added during the stirring of the mixture of the resin and the solvent, and were uniformly dispersed in the solution. Thereafter, a pigment paste and the remaining components were sequentially added to prepare a glittering pigment-containing coating composition.

[0076] effect pigment-containing coating compositions formulated Friend Color F500BL (Showa Aluminum Powder Co., Ltd. 7.0 colored aluminum) SDA-SILVER W-3 (Merck alumina flakes) 3.0 Degussa carbon FW-200 (Degussa Black pigment) 0.2 phthalocyanine blue 5206 (blue pigment manufactured by Dainichi Seika) 0.1 thermosetting acrylic resin (Nippon Paint Co., Ltd., hydroxyl value 45, 114.2 acid value 15, number average molecular weight 21000, Uban 20N60 44.9 (Butylated melamine resin manufactured by Mitsui Cytec, solid content 60%) Crosslinked resin particles (Nippon Paint Co., Ltd., solid content 20%) 9.0 Dispalon KS273N (Kusumoto Chemical Co., Ltd. Surface preparation agent) 0.2 n butanol 4.0 xylene 6.1 toluene 11.3 total 200.0 Resin solids / hardener solids ratio = 7/3 PWC = 10.3% Crosslinkable resin particle content (to resin solids ratio) = 2.0%

Forming Method of Composite Coating Film for Appearance Evaluation A zinc electrodeposited 0.8 mm thick, 10 cm × 30 cm dull steel plate was coated with a cationic electrodeposition paint, Powertop U-50.
(Product name, manufactured by Nippon Paint Co., Ltd.)
And baked at 160 ° C. for 30 minutes. Next, a gray intermediate coating on the obtained electrodeposition coating film,
Olga TO-H850 gray (trade name, manufactured by Nippon Paint Co., Ltd.) was spray-coated so as to have a dry film thickness of about 30 μm, and a baked coating film was formed at 140 ° C. for 20 minutes.

Example 1 was coated on the obtained gray intermediate coating film.
The bright pigment-containing coating composition prepared in the above was adjusted to ethyl acetate / toluene / solvesso 100 / solvesso 150 = 20 /
Using a thinner of 50/20/10, diluted with a No. 4 Ford cup at 20 ° C. for 13 seconds and adjusted in viscosity, an electrostatic coating machine (“Auto”) was adjusted to a dry film thickness of about 18 μm. REA ", manufactured by Ransberg Gema Co., Ltd.) and spray-painted with two-stage paint at an atomization pressure of 4 kg / cm2.
The setting was left for 3 minutes.

Next, in the wet-on-wet coating, Olga TO-563 Clear (trade name) paint shown below was coated with No. 4 Ford cup using Solvesso 100 / xylene = 60/40 diluted thinner. The mixture diluted for 20 seconds was coated so as to have a dry film thickness of about 30 μm, and after setting for about 7 minutes, baked at 140 ° C. for 20 minutes to prepare a coated plate for evaluation for evaluation.

Clear paint "Olga TO-563 Clear (trade name)" used for forming the composite coating film Acrylic resin / melamine resin-curable clear paint manufactured by Nippon Paint Co., Ltd. Resin solids / hardener solids ratio = 65/35 PWC = 0%

Evaluation of Coating Appearance Colorimetric color difference data was measured with a Minolta CR-354 variable color difference meter.

Criteria for Evaluation of Designability Ten persons who can evaluate the finish of the coating film are visually evaluated in a room where sunlight shines, with a part of the coated plate being exposed to sunlight, and the glitter (particles are shining) The results for the shining sensation and the feeling of depth (the sensation of light coming from inside the coating film) were comprehensively summarized according to the following criteria. 5; fairly good 4; excellent 3; normal feeling 2; slightly poor 1; fairly poor

Table 1 below shows the evaluation results of the above items.

Examples 2 to 3 Except that the types of colored aluminum and alumina flakes were changed as shown in Table 1 below, a coating composition containing a brilliant pigment was produced and evaluated in appearance according to the same procedure as in Example 1. A coated plate was prepared and evaluated. Table 1 shows the results.
Shown in

Comparative Examples 1 to 5 The composition of a brilliant pigment-containing coating composition was prepared in the same manner as in Example 1 except that the amount of colored aluminum added or mica powder was used instead of alumina flakes to change as shown in Table 1. The product was manufactured and a coated plate for appearance evaluation was prepared and evaluated. Table 1 shows the results.

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[Table 1]

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According to the present invention, there is provided a composite coating film in which a layer made of the bright pigment-containing coating composition of the present invention is formed on a base material which has been coated with an electrodeposition coating material and an intermediate coating material, and a clear coating layer is formed thereon. By adopting the forming method, it is possible to form an unprecedented brilliant and novel high-design composite coating film without deteriorating the finished appearance and the like.

Conventionally, when a colored aluminum pigment is combined with another pigment (including a brilliant pigment), the colored gloss derived from the colored aluminum pigment is buried and inconspicuous. However, the composite coating film formed by the glitter pigment-containing coating composition of the present invention has remarkable colored gloss,
Even when a coating color with high lightness and high saturation is set, a subtle change in colored gloss according to the degree of inclination of the coating film surface can be recognized, and the color tone changes variously depending on the viewing angle. Further, in the shade position where the gloss intensity is weak, the brilliant feeling and the translucency expressed by the combination of the colored gloss derived from the colored aluminum and the alumina flake pigment and / or other colored pigments are enhanced.

Therefore, for example, the viewing angle is different between the lower portion and the upper portion of a large area, and the lower portion has a higher gloss intensity and better color gloss, while the upper portion has a lower gloss intensity, and the alumina flake pigment and And / or other color pigments may combine to give rise to a prevailing color. in this case,
Different color tones coexist at the same time on one coating surface, and express a higher design effect than ever before.

Claims (5)

[Claims] 1. A glitter pigment-containing coating composition containing colored aluminum and alumina flakes as glitter pigments. 2. The bright pigment-containing coating composition according to claim 1, further comprising crosslinkable resin particles. 3. A method for forming a composite coating film on an undercoated substrate by two coats and one bake, wherein the first layer is formed from the glitter pigment-containing coating composition according to claim 1, and the second layer is formed as a second layer. 2. A clear coating film is formed.
A method for forming the composite coating film according to the above. 4. A composite coating film formed by the method according to claim 3. 5. An article having the composite coating according to claim 4.