JP2002275423A - Bright coating composition, method for forming coating film and multilayered coating film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bright coating composition for forming bright coating films which each has a shielding property, a light interfering property, enhanced light brightness and dense appearance due to the combination of both titanium dioxide-coated aluminum flakes and titanium dioxide-noncoated aluminum flakes, to provide a method for forming the coating film, and to provide a multilayered coating film. SOLUTION: This bright coating composition comprises a titanium dioxide- coated white aluminum flake pigment, a titanium dioxide-noncoated aluminum flake pigment, and a vehicle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a titanium dioxide-coated white aluminum flake pigment as a bright pigment,
The present invention relates to a glitter coating composition containing an aluminum flake pigment not coated with titanium dioxide and a vehicle, a coating film forming method, and a multilayer coating film obtained by this method.

[0002]

2. Description of the Related Art JP-A-2-142,862 discloses a brilliant paint containing a flaky colored aluminum pigment, and a brilliant paint containing a flaky colored aluminum pigment.
JP-A-70719 describes a glitter paint using a scale-like colored aluminum pigment and mica in combination. These glitter paints have a problem that a glitter coating film that satisfies both whiteness and hiding properties cannot be obtained.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a flip-flop effect by a composite using two kinds of aluminum flakes having a hiding property and a titanium dioxide coating or not. An effect in which a lightness difference that differs depending on the angle is expressed, hereinafter referred to as an “FF effect”), a glittering paint composition for forming a glittering coating film having improved brightness and whiteness, a coating film forming method, and a multilayer coating method. Is to provide a membrane.

[0004]

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. A brilliant coating composition comprising a titanium dioxide coated white colored aluminum flake pigment, an aluminum flake pigment not coated with titanium dioxide, and a vehicle. 2. The above glittering coating composition, wherein the coating amount of titanium dioxide of the titanium dioxide-coated white colored aluminum flake pigment is 50 to 300 parts by mass based on 100 parts by mass of aluminum flake. 3. The solid content ratio of the titanium dioxide-coated white colored aluminum flake pigment and the aluminum flake pigment not coated with the titanium dioxide is 99/1.
The glittering coating composition described above, wherein the composition is １／1/99. 4. The above glittering paint composition, wherein the total content of the titanium dioxide-coated white colored aluminum flake pigment and the aluminum flake pigment not coated with the titanium dioxide is 10 to 30% by mass based on the solid content of the paint. 5. A method for forming a coating film, wherein at least one of the layers constituting the multi-layer coating film is formed using the above glittering paint composition. 6. A method for forming a multilayer coating film on a substrate, in which an undercoating layer, an intermediate coating layer, a glittering coating layer, and a clear topcoating layer are sequentially formed, wherein the glittering coating layer is And a method for forming a coating film formed from the above glittering coating composition. 7. The above-mentioned method for forming a coating film, wherein the clear top coating film layer is formed from a coating material containing a carboxyl group-containing polymer and an epoxy group-containing polymer. 8. A multilayer coating film obtained by the above coating film forming method.

[0005]

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

Glittering paint composition The glittering paint composition of the present invention is a paint containing a titanium dioxide-coated white colored aluminum flake pigment, an aluminum flake pigment not coated with titanium dioxide, and a vehicle.

The glitter pigment used in the glitter coating composition is two kinds of aluminum flake pigments, one of which is coated with titanium dioxide and has a white color aluminum flake pigment (hereinafter referred to as "white aluminum flake pigment"). Flake pigment ”), and the other type is
An aluminum flake pigment not coated with titanium dioxide (hereinafter referred to as "aluminum flake pigment"). The white aluminum flake pigment is obtained by coating aluminum flake with titanium dioxide.

[0008] The above-mentioned titanium dioxide is coated on aluminum flakes to form white aluminum flake pigment by a conventional method of coating titanium dioxide on flake pigments such as mica. By adjusting the amount, a white aluminum flake pigment exhibiting a white interference color can be obtained. The preferable range of the coating amount of titanium dioxide is 50 to 300 parts by mass, and more preferably 100 to 200 parts by mass, based on 100 parts by mass of the aluminum flake. If the coating amount is less than 50 parts by mass, a white interference color may not be exhibited, and if it exceeds 300 parts by mass, the FF effect may not be obtained.

[0009] The white aluminum flake pigment, as the particle size, it is preferable that D ₅₀ is 5 to 30 [mu] m, also D ₉₀ is preferably 40 to 60 [mu] m. The thickness is preferably 0.2 to 3 μm. Further, those having high surface smoothness and a sharp particle size distribution are preferable because scattering of reflected light is small. In the present invention, D ₅₀ is the particle diameter when the cumulative amount in the relative cumulative particle diameter distribution curve is 50% in the long particle diameter distribution, and D ₉₀ is the relative cumulative particle diameter in the long particle diameter distribution. It means the particle diameter when the cumulative amount in the distribution curve is 90%.

Examples of the aluminum flake pigment used in combination with the above-mentioned white aluminum flake pigment include pigments conventionally used for metallic paints, and pigments obtained by subjecting aluminum flake to a surface treatment with various fatty acids such as oleic acid. .

[0011] The aluminum flake pigment, as the particle size, it is preferable that D ₅₀ is 5 to 30 [mu] m,
D ₉₀ is preferably 40 to 60 μm. The thickness is preferably 0.2 to 3 μm.

The solid content ratio of the white aluminum flake pigment to the aluminum flake pigment is preferably from 99/1 to 1/99, and this range is 99/100.
If it exceeds 1 (when the amount of the aluminum flake pigment is small), the FF effect may be insufficient,
If it is less than (when the amount of the white aluminum flake pigment is small), the whiteness may be insufficient.

The total content of the white aluminum flake pigment and the aluminum flake pigment is preferably from 10 to 30% by mass based on the solid content of the coating material.
If this range is less than 10% by mass, the concealing properties and glitter may not be sufficiently improved, and if it exceeds 30% by mass, the appearance of the coating film may be deteriorated.

On the other hand, the vehicle contained in the glittering coating composition of the present invention disperses the above pigment, and is composed of a resin for forming a coating film and, if necessary, a crosslinking agent.

As the resin for forming a coating film constituting the vehicle, for example, (a) an acrylic resin, (b) a polyester resin, (c) an alkyd resin, (d) a fluororesin,
(E) epoxy resin, (f) polyurethane resin, (g)
Examples thereof include polyether resins, and these can be used alone or in combination of two or more. In particular,
Acrylic resins and polyester resins are preferably used.

The acrylic resin (a) includes a copolymer of an acrylic monomer and another ethylenically unsaturated monomer. Examples of the acrylic monomer that can be used for the copolymerization include methyl, ethyl, propyl, n-butyl, i-butyl and t-acrylate of acrylic acid or methacrylic acid.
-Butyl, 2-ethylhexyl, lauryl, phenyl,
Esterified products such as benzyl, 2-hydroxyethyl and 2-hydroxypropyl, ring-opened adducts of caprolactone of acrylic acid or 2-hydroxyethyl methacrylate, glycidyl acrylate or methacrylate, acrylamide, methacrylamide and N-methylol Acrylamide, (meth) acrylic acid esters of polyhydric alcohols and the like can be mentioned. Examples of the other ethylenically unsaturated monomers copolymerizable therewith include styrene, α-methylstyrene, itaconic acid, maleic acid, and vinyl acetate.

Examples of the polyester resin (b) include saturated polyester resins and unsaturated polyester resins. Examples thereof include condensates obtained by heat-condensing a polybasic acid and a polyhydric alcohol. Examples of the polybasic acid include saturated polybasic acids and unsaturated polybasic acids.Examples of the saturated polybasic acids include phthalic anhydride, terephthalic acid, and succinic acid. For example, maleic acid, maleic anhydride, fumaric acid and the like can be mentioned.
Examples of polyhydric alcohols include dihydric alcohols and trihydric alcohols.
Examples include ethylene glycol and diethylene glycol, and examples of the trihydric alcohol include glycerin and trimethylolpropane.

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. It is also possible to use a lacquer type coating film forming resin having no curability and a curable type in combination.

When the vehicle contains a cross-linking agent, the ratio of the resin for forming a film to the cross-linking agent is 90 to 50% by mass and the content of the cross-linking agent is 10 to 50% by mass in terms of solid content. Preferably, the coating film forming resin is 85 to 60% by mass, and the crosslinking agent is 15 to 40% by mass. If the amount of the crosslinking agent is less than 10% by mass (the amount of the resin for forming a coating film exceeds 90% by mass), the crosslinking in the coating film is insufficient. On the other hand, if the crosslinking agent exceeds 50% by mass (the
), The storage stability of the coating composition is reduced and the curing speed is increased, so that the appearance of the coating film is deteriorated.

The glitter coating composition of the present invention may contain other glitter pigments and coloring pigments in addition to the above-mentioned white aluminum flake pigment and aluminum flake pigment.

Other glitter pigments include, for example, interference mica pigments, colored mica pigments, metal oxide-coated alumina flake pigments, metal oxide-coated glass flakes, metal-plated glass flakes, metal oxide-coated silica flake pigments, metal titanium Examples include flakes, graphite, stainless flakes, plate-like iron oxide, hologram pigments, and flake-like pigments composed of cholesteric liquid crystal polymers.

As the coloring pigment contained in the glittering base paint, if necessary, there may be mentioned those conventionally used for paints. Examples of such organic pigments include azo lake pigments and organic pigments. Phthalocyanine pigments, indigo pigments, perylene pigments, quinophthalone pigments, dioxazine pigments, quinacridone pigments,
Isoindolinone pigments, metal complex pigments and the like,
In addition, examples of the inorganic pigment include yellow iron oxide, red iron oxide, titanium dioxide, and carbon black.

The glitter coating composition of the present invention may further comprise, in addition to the above components, a polyamide wax which is a lubricating dispersion of an aliphatic amide, a polyethylene wax which is a colloidal dispersion mainly composed of polyethylene oxide, an anti-settling agent, Curing catalyst,
UV absorbers, antioxidants, leveling agents, surface conditioners such as silicone and organic polymers, anti-sagging agents, thickeners, defoamers, cross-linkable polymer particles (microgels), etc. are appropriately added and contained. be able to. These additives can improve the performance of paints and coatings by blending, for example, at a ratio of 15 parts by mass or less, respectively, to 100 parts by mass of the vehicle (based on solid content).

The glitter coating composition of the present invention is provided in a form in which the above components are usually 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 ethyl 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 coating film forming method of the present invention is a method of forming a multilayer coating film on a substrate, wherein at least one of the layers constituting the multilayer coating film is formed by the above-mentioned method. This is a method for forming a coating film using a glitter coating composition. As the multilayer coating film, for example, a top coating film layer is formed on the undercoat coating layer using the glitter coating composition, or a clear coating layer is formed on the coating film layer. Can be exemplified. In addition, the multilayer coating film,
It is preferable that the coating composition comprises an undercoating layer, an intermediate coating layer, a glittering coating layer, and a clear topcoating layer, and the glittering coating layer is preferably formed from the glittering coating composition.

The above-mentioned base material is not limited, and metals such as iron, aluminum, copper and alloys thereof; inorganic materials such as glass, cement and concrete; polyethylene resin, polypropylene resin, ethylene-vinyl acetate Copolymer resin, polyamide resin, acrylic resin,
Resins such as vinylidene chloride resin, polycarbonate resin, polyurethane resin and epoxy resin, and plastic materials such as various FRPs; natural and synthetic materials such as wood and fiber materials (paper, cloth, etc.); and processed products thereof. .

In the method for forming a coating film of the present invention, the above-mentioned glitter coating composition is applied to the above-mentioned substrate directly or via an undercoating layer. It is preferable to previously apply an undercoat to the base material by chemical conversion treatment, electrodeposition coating, spray coating, powder coating, or the like.

In the case where the glittering coating layer is formed directly on the undercoated coating layer without intermediate coating, wet-on-wet (W / W) or wet-on-dry ( W / D).

The above-mentioned W / W is a method of forming a lower layer coating film, drying the film by air drying or the like, and forming an upper layer coating film on an uncured or semi-cured lower layer coating film. On the other hand, the W / D is a method of forming an upper coating film on a lower coating film obtained by baking and curing a lower coating film.

It is also possible to apply each coating layer a plurality of times. In the case of baking the coating layer, 80 to 160
Perform baking at a temperature of ° C for a predetermined time. The dry thickness of the glittering coating layer is preferably 5 to 30 μm, more preferably 10 to 2 μm.
0 μm.

In the present invention, an intermediate coating layer can be formed before forming a glittering coating layer on the substrate. When an undercoat layer is formed below the intermediate coat layer, the undercoat layer is preferably formed by W / D with the undercoat layer. The intermediate coating film layer may be formed of a solvent-type paint, an aqueous paint, or a powder-type paint.
As the vehicle, pigment and optional additives to be used for forming the intermediate coating film layer, those exemplified for the glittering coating composition can be used.

The dry film thickness of the intermediate coating film layer is 20 to 1
If the thickness is outside this range, the appearance of the coating film may be degraded. More preferably, it is 30 to 50 μm.

Next, a glitter coating layer is formed on the intermediate coating layer by using the glitter coating composition. This glittering coating layer is preferably formed on the intermediate coating layer by W / D. The dry thickness of the glittering coating layer is preferably 5 to 30 μm, more preferably 10 to 2 μm.
0 μm.

Further, at least one of the clear top coat layers is formed as a top coat layer on the bright coat layer. When a large amount of glittering pigment is contained in the glittering coating layer, the smoothness of the surface can be improved by applying two or more clear paints. It is preferable to use the above-mentioned W / W for formation of the clear top coat layer. Also, when applying the clear paint multiple times,
What is necessary is just to bake after applying the final clear paint, and it is not necessary to completely cure at the stage of applying the clear paint in the early stage. The dry film thickness of the clear top coat layer is preferably from 20 to 100 μm, and if it is out of this range, the appearance of the coat may deteriorate. More preferably 30 to
50 μm.

As the clear top coat layer, a general clear paint can be used, and a so-called turbid clear coat layer having a translucent feeling may be used. Further, the clear top coat layer may be formed from a solvent type paint, an aqueous paint or a powder type paint. As the solvent-based paint or the water-based paint, a one-pack paint may be used, or a two-pack resin such as a two-pack urethane resin paint may be used. By forming the clear top coat layer on the glitter coating layer, it is possible to improve gloss and prevent the glitter pigment from being damaged. As the clear paint, those generally used for overcoating can be used, and a mixture of the above thermosetting resin and a crosslinking agent can be used. In particular, Tokuhei 8-1931
JP-A No. 5 (1999) -2002, when a paint containing a carboxyl group-containing polymer and an epoxy group-containing polymer is applied to a glittering coating layer by W / W to prevent acid rain, the glittering agent in the glittering coating layer Is preferably used from the viewpoint of not disturbing the orientation. In addition, these clear paints, if necessary, as long as the transparency is not impaired, a coloring pigment, an extender, a modifier, an ultraviolet absorber, a leveling agent,
Additives such as dispersants and defoamers may be included.

The multi-layer coating film of the present invention is obtained by the above-mentioned coating film forming method, is formed on a substrate, and is formed of a layer constituting the multi-layer coating film. At least one layer is a glitter coating layer formed using the glitter coating composition. Preferably, the multilayer coating film is formed of an undercoating film layer, an intermediate coating film layer, a glitter coating film layer, and a clear top coating film layer.

[0037]

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 mass part unless there is particular notice. The names of raw materials, paints, and equipment represent trade names unless otherwise specified.

Examples 1 to 7 and Comparative Examples 1 to 2 Preparation of base material A dull steel plate (length 300 mm, width 100 mm and thickness 0.8 mm) was treated with a zinc phosphate treating agent (trade name: "Surfdine SD2000", Japan). After the chemical conversion treatment using a paint (manufactured by Nippon Paint Co., Ltd.), the cationic electrodeposition paint (trade name: "Power Top U-50", manufactured by Nippon Paint Co., Ltd.) has a dry film thickness of 25 μm.
m was electrodeposited. Then at 160 ° C. for 30
After baking for half an hour, an intermediate coating ("Olga S-90 Sealer", manufactured by Nippon Paint Co., Ltd.) is applied by air spraying so as to have a dry film thickness of 40 [mu] m, and baked at 140 [deg.] C. for 30 minutes. A substrate was obtained.

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 mass),
White aluminum flakes as shown in Table 1 were obtained by blending a melamine resin (trade name: “Uban 20SE”, manufactured by Mitsui Chemicals, Inc., solid content 60% by mass) at a solid content mass ratio of 80:20. Pigments, aluminum flake pigments and, if necessary, other pigments were blended in the proportions shown in Table 1. In addition, as a comparative example, one containing no white aluminum flake pigment (Comparative Example 1) and one containing no aluminum flake pigment (Comparative Example 2) were used. Subsequently, the mixture was stirred and mixed with an organic solvent (mass ratio of toluene / xylene / ethyl acetate / butyl acetate = 70/15/10/5) so as to obtain an appropriate coating viscosity by using a stirrer to prepare a glittering paint.

The clear coating clear paint was used the following paint. A: Acrylic resin solvent-based clear paint (trade name: "Super Lac O-130 Clear", manufactured by Nippon Paint Co., Ltd.); B: Solvent-based clear paint comprising a blend of a carboxyl group-containing polymer and an epoxy group-containing polymer (trade name) :
"Macflow O-520 Clear", manufactured by Nippon Paint Co., Ltd.).

On the surface to be coated of the base material for forming the multi-layer coating film , a glitter coating film was applied with a glitter paint shown in Table 1 so as to have a dry film thickness of 30 μm.
Next, by W / W, the clear top coat layer was dried to a dry film thickness of 5
It was coated to a thickness of 0 μm to form a multilayer coating film. The baking condition was 140 ° C. for 20 minutes. The following evaluation items of the obtained coating film were evaluated by the following evaluation methods. Table 1 shows the results.

Evaluation Method Concealment: Concealment film thickness on black-and-white concealment paper was evaluated. FF effect: The brightness difference exhibited by the coating film was visually evaluated when the test piece after coating formation was viewed from almost right above (A) and when the test piece was viewed at an overhead angle of about 15 degrees with respect to the test piece (B). . 3... That the brightness differences presented in (A) and (B) are clearly different 2... That the brightness differences presented in each of (A) and (B) are different 1... Each in (A) and (B) Brightness difference is the same: Brightness: almost in front of the test plate (highlight part)
The luminosity when viewed in was evaluated visually. 3: Remarkable brilliant feeling 2: Slight brilliant feeling 1: No brilliant feeling Whiteness: The L value of the formed coating film was measured with a SM color computer (manufactured by Suga Test Instruments Co., Ltd.). 3 L value is 80 or more 2 L value is 60 or more and less than 80 1 L value is less than 60

[0043]

[Table 1]

As is clear from the results shown in Table 1, this example is a film obtained by forming a multi-layer coating film by the coating film forming method using the glittering coating composition of the present invention. A multi-layer coating film exhibiting a brilliant effect having an FF effect and whiteness was obtained.

On the other hand, in the comparative example, since the white aluminum flake pigment and the aluminum flake pigment were not used in combination, the multilayer coating film obtained in the above example was not obtained.

[0046]

The glitter coating composition of the present invention contains a white pigmented aluminum flake pigment coated with titanium dioxide, an aluminum flake pigment not coated with titanium dioxide, and a vehicle. The layer coating film can exhibit an FF effect, an increase in glitter, and whiteness by a composite using two types of aluminum flake pigments having a hiding property and the presence or absence of titanium dioxide coating.

Since the multi-layer coating film of the present invention exhibits the above-mentioned brilliant feeling, the brilliant coating of automobiles, motorcycles, etc., their parts, various container outer surfaces, coil coating, furniture, home appliance industry, communication industry, etc. Is preferably used in the field where is required.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C09C 1/64 C09C 1/64 3/06 3/06 C09D 5/29 C09D 5/29 7/12 7/12 201 / 06 201/06 201/08 201/08 F term (reference) 4D075 AE03 CA33 CA44 CB04 CB06 CB07 CB13 DA06 DB02 DB06 DB07 DB12 DB13 DB18 DB20 DB21 DB36 DB38 DB40 DB43 DB47 DB48 DB50 DB53 DB61 DC10 DC12 DC13 DC18 DC38 DC41 EA07 EA10 EA43 EB14 EB16 EB20 EB22 EB32 EB33 EB35 EB36 EB37 EB38 EB39 EB45 EB56 EC10 EC23 EC54 4F100 AA21A AB03B AB10A AK25A AK25E AK36A AK53E AL05A AL05E AT00B BA05 BA07 BA10B BA10E CA13A CC00A CC00C CC00D CC00E DE02A EH46C EH46D EJ68B GB16 GB31 GB32 GB81 JL10A JN01E JN21 JN21A 4J037 AA05 CA09 DD10 FF03 FF04 4J038 CD091 CG141 DB001 DD001 DD121 DD231 DF001 DG001 EA011 GA06 GA07 HA066 HA216 KA08 KA15 KA20 NA01 PA07 PB07 PC02 PC03 PC04 PC06 PC08 PC10

Claims (8)

[Claims] 1. A glittering coating composition comprising a titanium dioxide-coated white colored aluminum flake pigment, an aluminum flake pigment not coated with titanium dioxide, and a vehicle. 2. The glittering coating composition according to claim 1, wherein the coating amount of titanium dioxide of the titanium dioxide-coated white colored aluminum flake pigment is 50 to 300 parts by mass based on 100 parts by mass of aluminum flake. 3. The solid content ratio of the titanium dioxide-coated white colored aluminum flake pigment and the aluminum flake pigment not coated with the titanium dioxide is as follows:
The glittering coating composition according to claim 1, wherein the ratio is from 99/1 to 1/99. 4. The method according to claim 1, wherein the total content of the titanium dioxide-coated white colored aluminum flake pigment and the aluminum flake pigment not coated with the titanium dioxide is 10 to 30% by mass based on the solid content of the paint. 3. The glittering coating composition according to any one of 3. 5. A method for forming a coating film using the glitter coating composition according to claim 1 for forming at least one of the layers constituting the multilayer coating film. 6. An undercoat film layer, an intermediate coat film layer,
Glitter coating layer, a method of forming a multilayer coating film sequentially forming a clear top coating layer, wherein the glitter coating layer,
A method for forming a coating film formed from the glittering coating composition according to any one of claims 1 to 4. 7. The method according to claim 6, wherein the clear top coat layer is formed from a paint containing a carboxyl group-containing polymer and an epoxy group-containing polymer. 8. A multi-layer coating film obtained by the method for forming a coating film according to claim 5.