JP2001072933A - Brilliant coating composition, film-forming method and multi-layered coated film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition capable of giving a coated film exhibiting interference colors at a highlighted portion of the coated film, having a brilliant feeling causing neither shadow patches nor yellowish turbidity when formed on a pale color base coated film layer and having a good appearance by compounding a brilliant pigment comprising glass flakes and titanium oxide coated on the surface thereof and a vehicle. SOLUTION: A brilliant pigment has an average particle size of at least 10 μm and less than 80 μm in a state covered with titanium oxide. The content of the brilliant pigment in a brilliant coating composition is 0.01-30%. A vehicle is composed of a resin for forming a coated film and, if required, a crosslinking agent. The compounding ratio is such that the resin for forming a coated film and the crosslinking agent form 90-50 wt.% and 10-50 wt.%, respectively. As the resin for forming a coated film, there can be mentioned an acrylic resin, a polyester resin, an alkyd resin, a fluororesin, an epoxy resin, a polyurethane resin, a polyether resin and the like. Particularly preferable are an acrylic resin and a polyester resin.

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 containing a glitter pigment obtained by coating glass flakes with titanium oxide, a method for forming a coating film, and a multilayer coating film obtained by the method.

[0002]

2. Description of the Related Art Metallic paints using metallic pigments in which the surface of glass flakes is coated with silver or nickel are disclosed in JP-A-3-23969 and JP-A-5-191.
248. These metallic pigments can form a coating film exhibiting a brilliant sensation that is more brilliant than aluminum flake pigments.

[0003]

In the metallic pigment in which the surface of the glass flake is coated with silver or nickel, the formed coating film exhibits the above-mentioned strong glitter.
When changing the viewing angle of the coating film, the coloring effect due to interference in the highlight portion, which is the front, is not obtained, and when the coating layer containing the metallic pigment is formed on the light-colored color base coating layer, There is a problem that the shadow unevenness phenomenon in which the shadow of the coated metal occurs, and the formed coating layer becomes yellowish and a yellow tinge phenomenon occurs, resulting in a decrease in glitter, and a new design that solves these problems is desired. ing.

[0004] Therefore, the problem to be solved by the present invention is:
By coating the surface of glass flakes with titanium oxide,
It has an interference color in the highlight part of the formed coating film, and even when it is formed on a light-colored color base coating layer, it does not generate shadow unevenness and yellow tinge, and the coating appearance is good. An object of the present invention is to provide a glitter coating composition, a coating film forming method, and a multilayer coating film for forming a glitter coating film.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies in view of the above-mentioned problems, and as a result, have reached the present invention. 1. A glitter coating composition containing a glitter pigment having a surface coated with titanium oxide and a vehicle, and a vehicle. 2. When the average particle diameter of the glitter pigment is 10 μm or more, 8
The glitter coating composition according to claim 1, which has a thickness of less than 0 µm. 3. The solid content weight ratio (PWC) of the pigment to 100 parts by weight of the solid content of the bright pigment is 0.01 to 30%.
The glittering coating composition as described above. 4. A coating film forming method in which a glitter coating film is formed from the glitter coating composition as at least one of the multilayer coating films. 5. A coating film forming method for sequentially forming a base coating film layer, a glitter coating film layer formed of the above glitter coating composition, and a clear top coating film layer on a substrate. 6. The above-described coating film forming method, wherein the clear top coat layer is formed from a coating material containing a carboxyl group-containing polymer and an epoxy group-containing polymer. 7. A multilayer coating film obtained by the above coating film forming method.

[0006]

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

Glitter coating composition The glitter pigment used in the glitter coating composition of the present invention is a glitter pigment obtained by coating the surface of glass flakes with titanium oxide.

The brilliant pigment preferably has an average particle diameter of 10 μm or more when coated with titanium oxide.
It is less than 80 μm, more preferably 10 to 60 μm.
The average particle size in the present invention means the average particle size of the major axis. When the average particle size is less than 10 μm, it is difficult to exhibit a glittering effect exhibiting the interference color effect, and when the average particle size is 80 μm or more, the appearance of the coating film is poor. The thickness is 0.1 to 10 μm,
Preferably it is 0.1-5 μm. When the thickness is less than 0.1 μm, an excessive share is applied at the time of coating circulation, and the glittering pigment is deformed or broken, causing a problem that the coating is discolored with time. Might be. The interference color developed by the glitter pigment can be changed by adjusting the amount of titanium oxide to be coated (coating thickness). As these brilliant pigments, EXTERIOR MEARLIN FIRE
The MIST series (manufactured by Engelhard) is commercially available.

In the glitter coating composition of the present invention, the content of the glitter pigment (weight ratio of the solid content of the pigment to 100 parts by weight of the solid content of the paint: PWC) is preferably 0.01 to 30%, more preferably 1 to 15%. Is more preferred. If it is less than 0.01%, it is difficult to exhibit a brilliant effect exhibiting an interference color effect,
If it exceeds 30%, the coating film appearance may be deteriorated.

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

The resin for forming a coating film constituting the vehicle includes, 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.

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

Examples of the polyester resin (b) include saturated polyester resins and unsaturated polyester resins. Examples thereof include condensates obtained by heating and condensing a polybasic acid and a polyhydric alcohol. Examples of the polybasic acid include saturated polybasic acids 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 the polyhydric alcohol include dihydric alcohols and trihydric alcohols, and examples of the dihydric alcohol include ethylene glycol and diethylene glycol. Examples of the trihydric alcohol include:
Glycerin, trimethylolpropane and the like can be mentioned.

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

In the glitter coating composition of the present invention, in addition to the glitter pigment of the above-mentioned glass flakes coated with titanium oxide, other glitter pigments and coloring pigments may be added in an optional amount within a range that does not impair the effect of the glitter pigment. Can be contained.

Other brilliant pigments include, for example, aluminum flake pigment, colored aluminum flake pigment, mica pigment, metal titanium flake, alumina flake, silica flake, graphite, stainless steel flake, plate-like iron oxide or phthalocyanine flake, and the like. Examples of color pigments include, for example, azo lake pigments, phthalocyanine pigments, indigo pigments, perylene pigments, quinophthalone pigments, dioxazine pigments, quinacridone pigments, isoindolinone pigments, metal complex pigments, graphite, yellow iron oxide , Bengara, titanium dioxide, carbon black and the like. The amount of addition of other glitter pigments and coloring pigments can be arbitrarily set as long as the effect of the glitter pigment and the composite color effect with the underlayer are not hindered. Also, various extender pigments and the like can be used in combination.

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 antisettling 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. The performance of paints and coatings can be improved by blending these additives in a proportion of, for example, 15 parts by weight or less with respect to 100 parts by weight of the vehicle (based on solid content).

The glitter coating composition of the present invention is provided in a form in which the above-mentioned 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 ether ketone, esters such as ethyl acetate, cellosolve acetate, and butyl cellosolve, and alcohols. When the use of an organic solvent is regulated from the viewpoint of the environment, it is preferable to use water. In this case, an appropriate amount of a hydrophilic organic solvent may be contained.

The film forming method of a coating film forming method of the present invention is a method for forming a multilayer coating film on a substrate, at least one layer of the multilayer coating film is formed by the bright coating composition Coating film forming method.
Further, the multilayer coating film is composed of a base coating layer, a brilliant pigment-containing brilliant coating layer, and a clear top coat layer, and the brilliant coating layer is formed from the brilliant coating composition. This is a coating film forming method.

The above-mentioned substrate 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 glitter coating composition of the present invention is overcoated directly or via an undercoating layer on the base material. In the case where the multilayer coating film is an automobile body or a part, it is preferable that the base material is previously coated with a base coat such as a chemical conversion treatment, an electrodeposition coating, a powder coating or the like, or an intermediate coating. The intermediate coating is performed for hiding the base, imparting chipping resistance, and ensuring adhesion with the top coat.

In the method for forming a coating film according to the present invention, a wet-on-wet (W / W
W) or wet-on-dry (W / D) to form a glittering coating layer. The above-mentioned W / W is a method in which after forming a lower layer coating film, it is dried by air drying or the like, and applied to an uncured or semi-cured lower layer coating film. And a method in which the lower coating film is baked and applied to the cured lower coating film. The method for forming each coating layer is not particularly limited, but a spray method, a roll coater method, or the like is preferable, and each coating layer can be coated a plurality of times. When baking the coating layer,
Baking is performed at 80 to 160 ° C. for a predetermined time.

In the present invention, a base coating layer can be formed on the above-mentioned substrate before forming the glittering coating layer. When a coating layer is formed below the base coating layer, the base coating layer is preferably formed by W / D with the lower coating layer. The base coating layer may be formed of a solvent-type paint, a water-based paint, or a powder-type paint. As the vehicle, the pigment and the additives to be added as needed for the paint used for forming the base coating layer, those of the above-mentioned brilliant paint composition can be used.

When a transparent brilliant top coat layer is used, a complex color of the base coat layer and the top coat layer is developed to enhance the design, and a gray color is used. A base coating layer is formed by using a base paint or a color base paint. In this case, even if a color base coating layer having a lightness of N6 to 10 in the Munsell display system is formed, it is possible to exhibit a composite color without shading and yellowing. Further, when the base coating layer is a clear coating layer, even if the brightness of the lower coating layer or the base material of the clear coating layer is N6 to 10, it exhibits a complex color without shadow unevenness and yellowing. It becomes possible. In the present specification, the lightness is N6 to 10
The term refers to the brightness of the substrate when the glitter coating layer is formed directly on the substrate, and the brightness of the base coating layer when the base coating layer is formed, or When the layer is a clear coating layer, it refers to the brightness of the lower coating layer or the substrate.

On the other hand, when a glittering top coat layer having no transparency is used, the base coat layer is formed using a gray base paint.

The dry film thickness of the base coating layer is 10 to 100.
μm is preferable, and if it is out of this range, the appearance of the coating film may be deteriorated. More preferably, it is 20 to 50 μm.

Next, a glitter coating layer is formed on the substrate or the base coating layer using the glitter coating composition. This brilliant coating layer is composed of the base coating layer and the W
/ D is preferable. The dry thickness of the glittering coating layer is preferably 5 to 50 μm, more preferably 1 to 50 μm.
0 to 30 μm. Here, as the glitter coating composition, it is possible to impart transparency by adjusting the content and type of glitter pigments and coloring pigments. It is possible to develop a composite color with the layer and the base coating layer.

Further, on the bright coating layer, at least one clear top coating layer is formed as a top 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 10 to 100 μm, and if it is out of this range, the appearance of the coat may deteriorate. More preferably 20 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
When a clear paint containing a carboxyl group-containing polymer and an epoxy group-containing polymer described in Japanese Patent No. 5 is applied to a glittering coating layer by acid rain resistance and W / W, It is preferably used from the viewpoint of not disturbing the orientation of the glitter. In addition, these clear coatings may contain additives such as coloring pigments, extenders, modifiers, ultraviolet absorbers, leveling agents, dispersants, and defoaming agents as long as the transparency is not impaired. Can be included.

The multi-layer coating film of the present invention is formed by using at least one of the above-mentioned glittering coating layers. Preferably, the above-mentioned multi-layer coating film comprises a base coating layer and then a glitter coating layer. And a clear top coat layer. The brightness of the base coating layer is the brightness N6 in the Munsell display system.
Even when the value is from 10 to 10, shadow unevenness and yellow tingling can be prevented.

[0032]

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 13 and Comparative Examples 1 to 4 Preparation of Substrates to be Coated Dull steel plates (length 300 mm, width 100 mm and thickness 0.8 mm) were treated with a zinc phosphate treating agent (trade name: "Surfdine SD2000"). And Nippon Paint Co., Ltd.), and then a cationic electrodeposition paint (trade name: "Power Top U-50", manufactured by Nippon Paint Co., Ltd.) is adjusted to have a dry film thickness of 25 μm. Electrodeposited. Then 160
After baking at 30 ° C. for 30 minutes, the following base paint was applied by air spray coating so as to have a dry film thickness of 40 μm.
Baking was performed at 0 ° C. for 30 minutes to form a base coating layer. The substrates were 1A, 1B, and 1C, respectively. 1A ... Product name: "Olga S-90 Sealer (N9)"
Nippon Paint Co., Ltd., 1B ... Product name: Olga S-90 Sealer (N6),
Nippon Paint Co., Ltd., 1C ... Product name: Olga S-90 Sealer (N4),
Nippon Paint Co., Ltd., 1D ... 4 types of Nippon Paint Co., Ltd. brand name "Olga S-90 Sealer (N2)". (N9) in the product name,
(N6), (N4) and (N2) indicate the lightness of the Munsell display system.

Preparation of glittering paint 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);
The blending amount and color development are shown for 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. A brilliant pigment having an average particle diameter of 45 μm, in which the surface of the glass flakes shown in No. 1 was coated with titanium oxide, and other pigments as necessary were mixed in the proportions shown in Table 1. In addition, in the comparative example, a glitter pigment having an average particle diameter of 30 μm, in which silver was coated on the surface of the glass flake having the blending amount and coloring shown in Table 1, and other pigments as necessary were blended in the proportions shown in Table 1. Then, the mixture was stirred with an organic solvent (weight ratio of toluene / xylene / ethyl acetate / butyl acetate = 70/15/10/5) by a stirrer so as to obtain an appropriate coating viscosity to prepare a glittering paint.

The clear coating clear paint was used the following paint. 2A: Acrylic resin solvent-based clear paint (trade name:
"Super Lac O-130 Clear", manufactured by Nippon Paint Co., Ltd .; 2B ... Solvent-type clear coating composed of a blend of a carboxyl group-containing polymer and an epoxy group-containing polymer (trade name: "Macflow O-520 Clear", Nippon Paint Co., Ltd.) Manufactured).

On the surface to be coated of the base material on which the multi-layer coating film is to be formed , the above-mentioned base coating layer is dried to a thickness of 50 μm.
m, and then the glitter coating layer was coated with a glitter paint shown in Table 1 so as to have a dry film thickness of 30 μm. Next, the clear top coat layer was applied by W / W to a dry film thickness of 50 μm to form a multilayer coat. The baking condition was 140 ° C. for 20 minutes. The glitter of the obtained coating film was evaluated by the following evaluation method. Table 1 shows the results.

Evaluation method Glitter: Glitter when the test plate was viewed almost directly in front (highlight part) was visually evaluated. 3: There is remarkable glitter. 2: There is a little glitter. 1: No glitter. Color: The color development when the test plate was viewed almost directly in front (highlighted portion) was visually evaluated. 3: There is remarkable coloring. 2: There is little coloring. 1: No color development. Shadow unevenness: Yellow nigori when viewed at about 15 degrees (shade portion) was visually evaluated. 3: No yellow nigari was recognized. 2: Yellow nigori is slightly recognized. 1: Yellow nigori is remarkably recognized.

[0038]

[Table 1]

As is clear from the results shown in Table 1, in Examples 1 to 13, the coating film layer was formed by the coating film forming method containing the glitter pigment of the present invention, and the glittering color having interference color was obtained. When applied on a base coat layer having a lightness of N6 to 10, a multi-layer coating film free from shadow unevenness and yellowing was not obtained on the whole coating film. On the other hand, in Comparative Examples 1 to 4,
Since the metal-plated glass flake pigment was used, a glittering feeling with only glitter was emphasized without exhibiting interference color, and no interference color was exhibited.

[0040]

The glitter coating composition of the present invention contains a glitter pigment obtained by coating a surface of a glass flake with titanium oxide.
It is possible to exhibit a brilliant feeling exhibiting an interference color.

Further, even when a coating film formed by the glitter coating composition of the present invention is overcoated with a base coating layer having a lightness of N6 to 10, the color tone of the base coating layer and the glitter of the glitter pigment can be maintained. It is possible to provide a multi-layer coating film that is synthesized and exhibits an interference color free from shadow unevenness and yellowing as a whole coating layer.

Since the multi-layer coating film of the present invention exhibits the above-mentioned brilliantness and the above-mentioned color tone, it can be used for vehicle outer panels of automobiles, motorcycles, etc., these parts, outer surfaces of various containers, coil coating, furniture, home appliance industry, communication industry, etc. Is preferably used in the field where brilliancy is required.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09D 133/02 C09D 133/02 163/00 163/00

Claims (7)

[Claims] 1. A glitter coating composition comprising a glitter pigment and a vehicle, wherein the surface of a glass flake is coated with titanium oxide. 2. The glitter pigment has an average particle diameter of 10 μm.
The brilliant coating composition according to claim 1, which is less than 80 µm. 3. The solid content ratio (PWC) of the pigment to 100 parts by weight of the solid content of the brilliant pigment is 0.01% by weight.
The glittering coating composition according to claim 1, wherein the content is from 30% to 30%. 4. A method for forming a brilliant coating film using the brilliant coating composition according to any one of claims 1 to 3, as at least one of the multilayer coating films. 5. A base coat layer on a substrate, wherein the base coat layer is a base coat layer.
A coating film forming method for sequentially forming a glitter coating layer formed by the glitter coating composition according to any one of the preceding claims and a clear top coat layer. 6. The method according to claim 5, wherein said clear top coat layer is formed from a paint containing a carboxyl group-containing polymer and an epoxy group-containing polymer. 7. A multi-layer coating film obtained by the method for forming a coating film according to claim 4.