JP2000086945A - Brilliant coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a brilliant coating composition capable of providing a brilliant coating membrane having a covering properties, manifesting a strong brilliant feeling with transparency, and having both of circulation resistance and covering resistance by including a vehicle and a specific pigment. SOLUTION: This brilliant coating composition contains (A) a vehicle, (B) an alumina flake pigment coated with a metal oxide (preferably a flaky aluminum oxide pigment), and (C) (i) an aluminum flake pigment or (ii) a particulate titanium dioxide pigment. The content (PWC%) of the component B based on the composition is preferably 0.01-15%. If necessary, (iii) a mica pigment is used in combination as a combination pigment of the component C. The total content of the components B and C is preferably 0.01-25%, and the ratio of the components B to C in the composition is preferably (99/1)-(40/60) expressed in terms of weight. The coating membrane excellent in strong and transparent brilliant feeling and having a high-class feeling is provided by using the composition, and the composition can be suitably applied to a shell plating or the like of a vehicle such as an automobile.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glitter coating composition, a glitter coating film forming method, and a coated article coated by the method. More specifically, a combination of a metal oxide-coated alumina flake pigment exhibiting a strong, transparent luminance feeling, an aluminum flake pigment, a fine particle titanium dioxide pigment, and a mica pigment develops a luminance feeling that cannot be obtained conventionally, and is resistant to The present invention relates to a coating composition capable of providing a glittering coating film having both circulating properties and hiding resistance, a glittering coating film forming method, and a coated article coated by the method. The coating film obtained by the present invention is strong, and has a high-quality sense of transparency and excellent brightness, so that the outer appearance of vehicles such as automobiles and motorcycles, the outer surface of containers, coil coating, and the brilliancy of the home appliance industry, etc. It is preferably used in required coatings.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 10-183033 discloses a method of forming a multilayer coating film by applying a colored paint (A), an interference paint (B) and a clear paint (C). Discloses a method for forming a coating film which is an organic solvent-based coating material containing aluminum oxide powder coated with a metal oxide and mica powder coated with a metal oxide.

[0003]

The above-mentioned method for forming a coating film requires a colored coating layer as an essential layer under the interference coating film, and a material exhibiting a brilliancy due to a complex color development of the colored coating layer and the interference coating film. It is used as Therefore, it cannot be applied to a two-coat one-bake coating system in an automotive coating system because of no concealing property, and the glitter is also coated with a metal oxide-coated aluminum oxide powder and a metal oxide. To obtain a limited glittering coating with mica powder.

The present inventors have conducted intensive studies in view of the above-mentioned problems, and as a result, (1) a vehicle, (2) a metal oxide-coated alumina flake pigment (A), and (3) an aluminum flake pigment or a fine particle titanium dioxide pigment ( B-1), and that the coating composition having concealing properties provides a bright coating film that exhibits strong, transparent brightness, and has both circulation resistance and concealing resistance. The present invention has been completed.

[0005] The present invention provides a glitter coating composition capable of obtaining a coating film exhibiting excellent glitter, a method for forming a glitter coating film, and coating of preferably a car body / part, a container outer surface, etc., coated by the method. The purpose is to provide things.

[0006]

That is, the present invention provides a brilliant coating composition containing the following (1) to (3) and having a hiding property. (1) Vehicle, (2) Alumina flake pigment coated with metal oxide (A), and (3) Aluminum flake pigment or fine particle titanium dioxide pigment (B-1)

Another object of the present invention is to provide a glittering coating composition containing the following (1) to (3), having a hiding property and satisfying (4). . (1) a vehicle, (2) a metal oxide-coated alumina flake pigment (A), and (3) an aluminum flake pigment,
At least two or more pigments (B-2) (1) selected from fine-particle titanium dioxide pigments or mica pigments;
(4) (A) / (B-2) = 99/1 to 40/60 (weight ratio)

The present invention also provides, as an embodiment, a glittering coating composition characterized in that the metal oxide-coated alumina flake pigment is coated with titanium dioxide or diiron trioxide. is there.

The present invention also provides, as an embodiment, a glittering coating film comprising forming a basecoat coating film with the above glittering coating composition on a substrate to be coated, and then forming a topcoat coating film with a clear coating material. The present invention provides a forming method.

The present invention provides, as an embodiment, a method for forming a glittering coating film, wherein the clear coating contains a carboxyl group-containing polymer and an epoxy group-containing polymer.

Further, as an embodiment of the present invention, there is provided a method for forming a glitter coating film, which comprises forming a clear top coat coating film after forming a base coat film using the glitter coating composition on an object to be coated. To provide.

Further, as an embodiment of the present invention, there is provided a coated article characterized in that a coating film is formed by the above-mentioned coating film forming method.

[0013]

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

"(1) Vehicle" (1) used in the present invention
The vehicle contains (2) a metal oxide-coated alumina flake pigment, (3) an aluminum flake pigment, a fine particle titanium dioxide pigment, a mica pigment (hereinafter sometimes referred to as a "combination pigment"), and the like. It comprises a film-forming resin and, if necessary, a crosslinking agent.

Examples of the resin for forming a coating film constituting the vehicle include an acrylic resin, a polyester resin, an alkyd resin, a fluororesin and the like. In particular, an acrylic resin and a polyester resin are preferably used. Usually, it is used after being mixed with a crosslinking agent such as an amino resin or a blocked polyisocyanate compound. Also, these resins are
Not only one type but also two or more types can be used in combination. Alternatively, a thermoplastic resin such as a thermoplastic acrylic resin that can be cured by drying at room temperature, a two-component urethane resin, or a silicone resin can be used.

<Blending Ratio> The blending ratio of the coating film forming resin and the crosslinking agent is 90 to 90% in terms of solid content.
It is 50% by weight, preferably 85-60% by weight, and the crosslinking agent is 10-50% by weight, preferably 15-40% 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, if the cross-linking agent exceeds 50% by weight (the resin for forming a coating film is less than 50% by weight), the storage stability of the coating composition is reduced and the curing speed is increased.

"(2) Metal oxide-coated alumina flake pigment" The metal oxide-coated alumina flake pigment used in the glittering coating composition of the present invention is not particularly limited, but is described in, for example, JP-A-9-77512. The flaky aluminum oxide pigment which has been used can be suitably used.

That is, aluminum oxide (A12O
3) is coated with a metal oxide such as Fe2O3, TiO2, SnO2, ZrO2, and has an average particle size of 3 to 60.
μm, preferably 5 to 30 μm, and a thickness of 0.1 to 0.8.
μm, preferably 0.2 to 0.4 μm. 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 0 or more flaky aluminum oxide pigments is coated with the metal oxide, the pigments have a pearly (pearl luster). 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.

Examples of the metal oxide-coated alumina flake pigment include SDA series such as "SDA-SILVER W-3 (trade name)" sold by Merck Japan KK.

By changing the type and amount of metal oxide, these can cover from silver color to copper color and senna color interference color. When exposed to high light such as sunlight, it is possible to provide a coating film having a paint color having a particularly strong glittering feeling.

The content (PWC%) of the metal oxide-coated alumina flake pigment in the glitter coating composition is 0.0
The content is preferably 1% to 15%, and if it exceeds 15%, the appearance of the coating film decreases, and if it is less than 0.01%, the sense of brightness decreases. More preferably, it is 0.1% to 14%, and still more preferably, it is 1% to 12%.

"(3) Combined pigments" Aluminum flake pigments (including colored aluminum flake pigments) and fine particle dioxide are used in combination with the glitter coating composition of the present invention in combination with the metal oxide-coated alumina flake pigments. The titanium pigment and, if necessary, the mica pigment can exert an effect when used in combination with each other. In addition, the above-mentioned metal oxide-coated alumina flake pigment and aluminum flake pigment, fine particle titanium dioxide pigment, a glittering pigment-containing coating layer in which mica pigment is used in combination with a clear coating layer, and a composite coating By doing so, a composite coating film having an unprecedented new design property can be obtained.

When the aluminum flake pigment is used in combination, the strong and transparent brightness of the metal oxide-coated alumina flake pigment, the metal feeling and the concealing property are further enhanced. The circulation resistance is improved as a whole.

The use of the fine particle titanium dioxide pigment together with the metal oxide-coated alumina flake pigment makes it possible to maintain the strong and transparent brightness and to improve the color flop characteristics of different colors depending on the viewing angle. Coating film is obtained. However, in this case, it is preferable to add a pigment having a masking property in order to provide the masking property.

By using the aluminum flake pigment and the fine particle titanium dioxide pigment together, the strong and transparent brightness of the metal oxide-coated alumina flake pigment is further enhanced, and the metal feeling is enhanced. Is given, and the circulation resistance is improved as a whole,
A coating film having different colors depending on the viewing angle and having good color flop properties is obtained.

By using the aluminum flake pigment and the mica pigment together, the metal oxide-coated alumina flake pigment has a strong and transparent brightness, a more metallic feeling and a concealment property. In addition, a coating film having improved circulation resistance as a whole and further having a pearly feeling can be obtained.

A color flop having different colors depending on the viewing angle while maintaining a strong and transparent brightness, which is possessed by the metal oxide-coated alumina flake pigment, by using the fine particle titanium dioxide pigment and the mica pigment together. A coating film having both properties and a pearly feeling is obtained. However, in this case, it is preferable to add a pigment having a masking property in order to provide the masking property.

By using the aluminum flake pigment, the fine particle titanium dioxide pigment and the mica pigment together, the metal oxide-coated alumina flake pigment has a strong,
Transparent brightness, more metallic feeling, more concealment, improved overall circulation resistance, better color flop with different colors depending on viewing angle, more pearly A combined coating is obtained.

The total content of the alumina flake pigment and the pigment used together (PWC%) used in the glittering coating composition of the present invention.
Is preferably 0.01% to 25%, and if it exceeds 25%, the appearance of the coating film is reduced, and if it is less than 0.01%, the sense of brightness is reduced. More preferably, it is 0.1% to 20%, and still more preferably 1% to 17%.

In the glitter coating composition of the present invention, the content ratio of the metal oxide-coated alumina flake pigment and the combined pigment is set to 99/1 to 40/60 (weight ratio) as described above. It is possible to enhance a unique brightness feeling, and to provide a strong and transparent coating film that could not be obtained with conventional metal oxide coated alumina flake pigments or combined pigments alone from the highlight and shade positions it can.

Depending on the coating color, an organic or inorganic coloring pigment or extender can be used in combination.

"Other brilliant pigments" As brilliant pigments other than those used as combined pigments used in the present invention, pigments conventionally used for paints are used.
Metal titanium flakes, stainless steel flakes, plate-like iron oxide, phthalocyanine flakes or metal-plated glass flakes, etc. are arbitrarily set with an addition amount in a range that does not hinder the effects of the metal oxide-coated alumina flake pigment and the combined pigment,
Can be used.

"Other Color Pigments" As the other color pigments used in the present invention, those conventionally used for paints are conventionally used. Examples of organic pigments include azo lake pigments, phthalocyanine pigments, and indico pigments. Pigments, berylen-based pigments, quinophthalone-based pigments, dioxazine-based pigments, quinacridone-based pigments, isoindolinone-based pigments, metal complex pigments, and the like, and, as the inorganic pigments, for example, graphite, yellow iron oxide, red iron oxide, Titanium dioxide and the like can be mentioned. The addition amount of the other coloring pigments can be arbitrarily set according to the hue as long as the effects of the metal oxide-coated alumina flake pigment and the combined pigment are not hindered.

"Solvent" The glitter coating composition of the present invention is usually provided in a form in which the above essential components are dissolved and dispersed in a solvent. The solvent may be any one that dissolves and disperses the vehicle, and may be used as an organic solvent type, a non-aqueous dispersion type, an aqueous solution type, or an aqueous dispersion type. Therefore, it is preferable to use an aqueous system. In the case of an aqueous system, an appropriate amount of a hydrophilic organic solvent may be contained. Examples of the organic solvent 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.

"Other additives" The glitter coating composition of the present invention contains, in addition to the above essential components, extender pigments, antisettling agents, curing catalysts, ultraviolet absorbers, antioxidants, leveling agents, silicones, A surface conditioner such as an organic polymer, a sagging agent, a thickener, a defoaming agent, a lubricant, a crosslinkable polymer particle (microgel), and the like can be appropriately added. The performance of paints and coatings can be improved by blending these additives at a ratio of 5 parts by weight or less based on 100 parts by weight of the vehicle (based on solid content).

<Anti-settling agent> As an anti-settling agent, polyamide wax which is a lubricating dispersion of aliphatic amide and polyethylene wax which is a colloidal dispersion mainly composed of polyethylene oxide are preferable.

The first method for forming a bright coating film of the present invention is characterized in that after forming the base coat film with the above-mentioned glitter coating composition of the present invention, a top coat film is formed with a clear paint. Providing a coating system (I) comprising a base coat containing (2) a metal oxide-coated alumina flake pigment and (3) an aluminum flake pigment or a fine particle titanium dioxide pigment (B-1). It is.

The second method for forming a glittering coating film of the present invention is characterized in that after forming the base coating film with the above-described glittering coating composition of the present invention, a topcoat coating film with a clear paint is formed. And a base coat comprising at least two types of pigments selected from (2) metal oxide-coated alumina flake pigments and (3) aluminum flake pigments, particulate titanium oxide pigments or mica pigments (B-2 ) Is contained in the coating system (II).

"Coated object (substrate)" The coated object (substrate) of the coated object to be applied by the glitter coating composition and the glitter coating film forming method of the present invention may be iron, aluminum, copper or any of these. Metals such as alloys; inorganic materials such as glass, cement and concrete; polyethylene resin, polypropylene resin, ethylene-vinyl acetate copolymer resin, polyamide resin, acrylic resin, vinylidene chloride resin, polycarbonate resin, polyurethane resin, epoxy resin, etc. And plastic materials such as various FRPs; natural or synthetic materials such as wood and fiber materials (paper, cloth, etc.).

The coating composition is applied to the substrate to be coated directly or through an undercoat film. In the case of coating the body and parts of an automobile, it is preferable to apply a chemical conversion treatment, an electrodeposition coating, an intermediate coating, etc. in advance. preferable.

"Coating film forming method" A glitter coating composition is applied on a substrate to form a glitter coating film of a base coat, and at least one layer of clear paint is applied as a top coat on the glitter coating film obtained. Apply. It is suitably used for automobile bodies and parts.

<Base coat: brilliant coating film> In the case of using a substrate coated with an undercoat with an intermediate coating or the like,
The glitter coating composition is applied on the undercoating film by a wet-on-wet (W / W) method or a bake-on-wet (B / W) method. The W / W method is a method in which an undercoating film is formed and then dried by air drying or the like, and then applied in an uncured or semi-cured state. The B / W method is a method in which the undercoating film is applied after baking. It is. The coating method is not particularly limited, but a spray method, a roll coater method and the like are preferable. The dry film thickness of the glittering coating film is preferably 5 to 50 μm, and 10 to 30 μm
Is more preferred.

<Topcoat: Clear Coating> At least one topcoat clear coating is formed on the basecoat coating. If the base coating composition contains a large amount of brilliant pigments, applying two or more layers of the clear varnish improves the brilliancy on the surface. The clear coating may be any of those commonly used for topcoats. The application of the clear paint on the coating film of the present invention can be performed by a wet-on-wet (W / W) method. When the clear paint is applied a plurality of times, it may be baked after the final clear coat is applied, and may be in a W / W, plate or semi-cured state at the stage of forming the lower clear coat. The baking temperature after clear coating may be 120 to 160 ° C. The dry film thickness of the clear coating film is preferably from 10 to 80 µm, more preferably from 20 to 50 µm.

The composition of the clear paint is (i) a mixture of at least one thermosetting resin selected from an acrylic resin, a polyester resin, a fluororesin and a modified resin thereof and the above-mentioned crosslinking agent, or (Ii) A vehicle comprising a carboxyl group-containing polymer and an epoxy group-containing polymer can be used. From the viewpoint of acid rain resistance and to increase the difference in solubility with the base coat paint, (ii) a carboxyl group-containing polymer and A composition containing a vehicle comprising an epoxy group-containing polymer (see Japanese Patent Publication No. H8-19315) is preferable. Further, as a preferable composition, additives such as a pigment, a modifier, an ultraviolet absorber, a leveling agent, a dispersant, and an antifoaming agent can be added to the transparent resin as long as the transparency is not impaired.

[0046]

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 10, Comparative Examples 1 to 5" Preparation of substrate to be coated Dull steel plate (length 300 mm, width 100 mm and thickness 0.
8 mm) with a zinc phosphate treating agent (“Surdyne SD200”).
0, manufactured by Nippon Paint Co., Ltd.), and then the cationic electrodeposition paint (“Power Top U-50”, manufactured by Nippon Paint Co., Ltd.) was dried to a dry film thickness of 25 μm. I painted. Then, after baking at 160 ° C. for 30 minutes, the intermediate coating (“Olga S-90 Sealer Gray (N
-6) ", manufactured by Nippon Paint Co., Ltd.)
m at 30 ° C at 140 ° C
Baking for minutes, an intermediate coating film was formed.

2. Preparation of glitter coating composition Acrylic resin (styrene / methyl methacrylate / ethyl methacrylate / hydroxyethyl methacrylate /
Methacrylic acid copolymer, number average molecular weight about 20,000
0, hydroxyl value 45, acid value 15, solid content 50% by weight);
A (A) alumina flake pigment was added to a vehicle obtained by blending a melamine resin (trade name, “Uban 20SE”, manufactured by Mitsui Chemicals, Inc., solid content 60% by weight) at a solid content weight ratio of 80:20. , (B) a brilliant pigment and (C) a color pigment were blended in proportions shown in Table 1. Then, the organic solvent (toluene / xylene / ethyl acetate / butyl acetate weight ratio = 70)
/ 15/10/5) with a dissolver to stir and mix so as to have an appropriate coating viscosity to prepare a glittering coating composition. (A) Alumina flake pigment is (alumina flake A: titanium oxide-coated alumina flake pigment,
Alumina flake B: iron oxide-coated alumina flake pigment, both manufactured by Merck Co .; and (B) glittering pigment: mica pigment (“Iliodin 103WII”, manufactured by Merck Co.)
And aluminum flake pigment ("Aluminum paste MH")
8801 "(manufactured by Asahi Kasei Kogyo Co., Ltd.) and fine particle titanium oxide pigment (" Taipeku TTO-55B ", manufactured by Ishihara Sangyo Co., Ltd.) is used. The loadings were used.

3. Formation of glittering coating film The glittering coating composition is dried on the surface to be coated of the substrate to a thickness of 1
The coating was performed so as to be 5 μm. The coating is performed by an electrostatic coating machine ("A
auto REA ", manufactured by Landsberg Gemma Co., Ltd.) at an atomization pressure of 2.8 kg / cm2. The atmosphere in the booth during coating was maintained at a temperature of 25 ° C. and a humidity of 75%. After coating, set for 3 minutes and dry paint to a dry film thickness of 35μm
Paint, set at room temperature for 10 minutes,
Baking at a temperature of 140 ° C. for 30 minutes. The hiding power and chroma of the obtained coating film were evaluated by the following evaluation methods. The results are shown in "Table 1". The clear paint used was (1) an acrylic / melamine resin clear paint (trade name: “Super Luck 0-130 Clear”, manufactured by Nippon Paint Co., Ltd.) or (2) a carboxyl group-containing polymer and an epoxy group-containing polymer. Paint ("Macflow 0-520 Clear", manufactured by Nippon Paint Co., Ltd.)
There are two types. Table 1 shows the results.

Evaluation method Luminance: The luminosity when the test plate was viewed almost directly from the front (highlight portion) was visually evaluated. 5: Very high luminosity 4 ... High luminosity 3 ... High luminosity 2 ... Low luminosity 1 ... Very low luminosity

Color flop property: The difference in bluish whiteness when the test plate was viewed almost directly in front (highlight area) and about 15 degrees (shade area) was visually evaluated. 5: The difference in bluishness is very strong 4 ... The difference in bluishness is strong 3 ... There is a slight difference in bluishness 2 ... There is almost no difference in bluishness 1 ... There is no difference in bluishness

Concealment: The white / black difference when a glitter paint was applied to a black and white concealment test paper at a dry film thickness of 15 μm was visually evaluated. 5: no sensation of white / black difference and very good concealment property 4 ... no sensation of white / black difference and good concealment property 3 ... feel a slight difference of white / black 2: sensation of white / black difference and concealment Poor 1 Senses white / black difference strongly and has very poor concealment

Circulation resistance: brilliant paint 50
A mixture of 0 g and 100 g of glass beads was stirred with a disper for 2 hours, and the difference in hue and brightness before and after stirring was visually evaluated. 5: There is no difference in hue and brightness before and after stirring 4 ... There is a slight difference in either hue and brightness before and after stirring 3 ... There is a slight difference in both hue and brightness before and after stirring 2 … There is a difference before and after agitation 1… The difference is very large before and after agitation

[0054]

[Table 1]

[0055]

The present invention provides a metal oxide-coated alumina flake pigment exhibiting a strong and transparent brightness, an aluminum flake pigment exhibiting a metallic tone, a fine particle titanium dioxide pigment exhibiting a color flop property, and a pearl. In combination with a mica pigment expressing a tone, a luster coating composition exhibiting a previously unobtainable sense of brightness, having both circulation resistance and concealment resistance, a luster coating film forming method and coated by the method Painted products can now be provided. In addition,
Since the coating film obtained by the present invention is strong and has a high-grade feeling with excellent transparency and brightness, it is required to have glittering properties such as automobiles, motorcycles and other vehicle outer plates, container outer surfaces, coil coating, and the home appliance industry. It is preferably used in painted objects.

[Procedure amendment]

[Submission date] November 10, 1998 (1998.11.
10)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0049

[Correction method] Change

[Correction contents]

3. Formation of glittering coating film The glittering coating composition is dried on the surface to be coated of the substrate to a thickness of 1
The coating was performed so as to be 5 μm. The coating is performed by an electrostatic coating machine ("A
auto REA ", manufactured by Landsberg Gemma Co., Ltd.) at an atomization pressure of 2.8 kg / cm2. The atmosphere in the booth during coating was maintained at a temperature of 25 ° C. and a humidity of 75%. After coating, set for 3 minutes and dry paint to a dry film thickness of 35μm
Paint, set at room temperature for 10 minutes,
Baking at a temperature of 140 ° C. for 30 minutes. Of the resulting coating
Brightness, color flop, concealment, circulatory resistance
The property was evaluated by the following evaluation method. The results are shown in "Table 1". The clear paint used was (1) an acrylic / melamine resin clear paint (trade name: "Super Luck 0-
130 Clear ", manufactured by Nippon Paint Co., Ltd.)
(2) Clear paint ("Macflow 0-520 Clear", manufactured by Nippon Paint Co., Ltd.) comprising a blend of a carboxyl group-containing polymer and an epoxy group-containing polymer
Kind. Table 1 shows the results.

Claims (2)

[Claims] 1. A vehicle, (2) a metal oxide-coated alumina flake pigment (A), and (3) an aluminum flake pigment or a fine particle titanium dioxide pigment (B-1),
And a brilliant coating composition having concealing properties. 2. At least two or more pigments selected from (1) a vehicle, (2) an alumina flake pigment coated with a metal oxide (A), and (3) an aluminum flake pigment, a particulate titanium oxide pigment or a mica pigment. (B-2) and (4) (A) / (B-2) = 99/1 to 40/6.
A glittering coating composition which satisfies 0 (weight ratio) and has a hiding property.