JP2000204296A - Dichroic paint composition, manufacture of dichroic coating film, and dichroic painting material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dichroic paint composition which makes a calm dichro ism possible that shows different color developments display depending on viewing angles, a manufacture method of a dichroic film, and its painting mate rial. SOLUTION: The dichroic paint composition comprises (1) a vehicle, (2) an aluminum flake or a flake pigment coated with a metal oxide on an outer surface of a base, MIO coated with silicate dioxide, according to demand (3) at least a pigment selected from among a luster pigment and a coloring pigment. Manufacture of a dichroic coating film, and its painting material are carried out using the dichroic composition. The composition is preferably used for an automotive body/part, a container outer surface or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dichroic coating composition, a method for forming a dichroic coating film, and a coated article coated by the method. More specifically, a flake pigment in which aluminum flake or MIO exhibiting calm dichroism is used as a base material, the base material is coated with silicon dioxide, and the outer layer is coated with a metal oxide, and if necessary, other brilliant pigments The present invention relates to a coating composition capable of providing a dichroic coating film which has not been obtained conventionally by combining a coloring pigment and a coloring pigment, a method for forming a dichroic coating film, and a coated article coated by the method. In addition, since the coating film obtained by the present invention is excellent in calm dichroism and has a high-class feeling, dichroic properties are required for automobile outer panels, outer surfaces of containers for vehicles such as motorcycles, coil coating, home appliance industry, and the like. It is preferably used in painted objects.

[0002]

2. Description of the Related Art Conventionally, to obtain a coating film having dichroism,
A high chroma durable paint comprising a liquid polymer paint medium and a plurality of interference platelets dispersed in said liquid medium, wherein said platelets each have a metal reflector having first and second surfaces. Wherein the platelets have an aspect ratio of at least 2: 1 with respect to the longest plane dimension of the plane parallel to each layer plane and the platelet thickness in each layer plane. A polymer vehicle paint, wherein the plate has a maximum dimension of about 2 to 200 microns on any surface, is described in JP-A-9-508172.

[0003]

The above-mentioned interference platelet has two
It is used as a very good material from the viewpoint of expressing color properties. However, although very dynamic dichroism is developed, it is hard to say that it is calm dichroism.
In order to exhibit dichroism, strict quality control is required when manufacturing interference platelets, and an increase in cost cannot be avoided.

The inventors of the present invention have made intensive studies in view of the above-mentioned problems, and as a result, have found that a flake pigment and a vehicle, each of which is made of aluminum flake or MIO, is coated with silicon dioxide, and its outer layer is coated with a metal oxide. Was found to be obtained in a coating composition, and a dichroic coating film exhibiting excellent calm and excellent dichroism was obtained, thereby completing the present invention.

The present invention relates to a dichroic coating composition capable of obtaining a coating film exhibiting excellent dichroism, a method for forming a dichroic coating film, and preferably the outer surface of an automobile body / part or container coated by the method. The purpose is to provide painted objects such as

[0006]

That is, the present invention provides a dichroic coating composition characterized by containing the following (1) and (2). (1) vehicle, and (2) aluminum flake or MI
Flake pigment comprising O as a base material, the base material coated with silicon dioxide, and the outer layer coated with a metal oxide

Another object of the present invention is to provide a dichroic coating composition containing the following (1) to (3). (1) selected from a vehicle, (2) a flake pigment in which aluminum flake or MIO is used as a base material, the base material is coated with silicon dioxide, and the outer layer is coated with a metal oxide, and (3) a bright pigment or a coloring pigment. At least one pigment

Further, the present invention provides a flake pigment comprising the above-mentioned aluminum flake or MIO as a base material, the base material coated with silicon dioxide, and the outer layer coated with a metal oxide, based on 100 parts by weight of the solid content of the paint. , 0.01 to 30 parts by weight of solid content.

Further, the present invention provides, as an embodiment, a flake pigment in which the above-mentioned aluminum flake or MIO is used as a base material, the base material is coated with silicon dioxide, and the outer layer is coated with a metal oxide, such as titanium dioxide or trioxide. A dichroic coating composition characterized by being coated with diiron.

In another embodiment of the present invention, the glitter pigment is an aluminum flake pigment, a mica pigment,
A dichroic paint composition characterized by being at least one selected from graphite pigment, alumina flake pigment, metal titanium flake, stainless flake, plate-like iron oxide, phthalocyanine flake or metal-plated glass flake. is there.

Further, the present invention provides a method for forming a dichroic coating film, which comprises forming a clear top coat coating film after forming a base coat film with the dichroic coating composition on an object to be coated. Is what you do.

Further, the present invention provides a coated article characterized in that a coating film is formed by the above-mentioned coating film forming method.

Further, the present invention provides, as an embodiment, a coated object characterized in that the object to be coated is an automobile body / part or an outer surface of a container.

[0015]

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 is selected from (2) flake pigments in which aluminum flake or MIO is used as a base material, the base material is coated with silicon dioxide, and the outer layer is coated with a metal oxide, and if necessary, (3) brilliant pigments or color pigments are selected. At least one pigment or the like dispersed therein, and is composed of a resin for forming a coating film and, if necessary, a crosslinking agent.

Examples of the coating film forming resin constituting the vehicle include 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 may be used.

<Blending Ratio> The blending ratio of the resin for forming a coating film 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) Flake pigment in which aluminum flake or MIO is used as a base material, the base material is coated with silicon dioxide, and the outer layer is coated with a metal oxide." Aluminum flake or MIO (Miceous Iron) used in the present invention.
Oxide (mica-like iron oxide) as a base material, the base material is coated with silicon dioxide, and the outer layer is coated with a metal oxide. The flake pigment coated with a metal oxide having good dichroism is obtained. The base material thickness is preferably from 0.1 to 5 μm, more preferably from 0.1 to 2 μm, the major axis is preferably from 10 to 50 μm, more preferably from 15 to
30 μm, silicon dioxide coating thickness is 100-500n
m is preferable, and more preferably 300 to 450 nm. The metal oxide coating the outermost layer is silicon dioxide flake coated with iron oxide (iron monoxide or diiron trioxide) or titanium dioxide. The thickness of the coating layer is 10 to
120 nm is preferred, and more preferably 20 to 80 nm.
It is. A flake pigment in which the aluminum flake or MIO is used as a base material, the base material is coated with silicon dioxide, and the outer layer of the flake pigment is coated with a metal oxide,
Since O is used, the opaqueness is provided as compared with a plurality of interference platelets described in Japanese Patent Application Laid-Open No. 9-508172, and calm dichroism is exhibited.

"Glitter pigment" As the glitter pigment used in the present invention, those conventionally used for paints are conventionally used. For example, aluminum flake pigments (leafing type, non-leafing type), colored aluminum flake pigments, Mica pigment (titanium dioxide coated mica,
Colored mica, metal plated mica), graphite pigment,
Examples include alumina flake pigment, metal titanium flake, stainless flake, plate-like iron oxide, phthalocyanine flake, and metal-plated glass flake.

"Coloring pigment" The coloring pigment used in the present invention includes:
Conventionally used for paints are used,
Examples of the organic pigment include an azo lake pigment, a phthalocyanine pigment, an indico pigment, a berylen pigment, a quinophthalone pigment, a dioxazine pigment, a quinacridone pigment, an isoindolinone pigment, a metal complex pigment, and the like. Examples of the inorganic pigment include, for example, graphite, yellow iron oxide, red iron oxide, titanium dioxide, fine particle titanium dioxide, and the like. The addition amount of the coloring pigment can be arbitrarily set in accordance with the hue as long as the coating film retains dichroism.

Aluminum flake or MI used in the present invention
The flake pigment having O as a base material, the base material coated with silicon dioxide, and the outer layer coated with a metal oxide has a paint solid content of 10%.
The amount is preferably 0.01 to 30 parts by weight of solid content with respect to 0 parts by weight. If the amount is less than 0.01 solid parts by weight, it is difficult to obtain a dichroic coating film, and if it exceeds 30 parts by weight, a smooth coating film is difficult to be selected and various properties required for the dichroic coating film And storage stability of the paint may be impaired. More preferably, in the case of forming a composite color with the hue of the base (the dichroic coating film has no base concealing property: when the object to be coated is an automobile / body, etc., it is called 3 coats 2 bake)
0.1 to 20 parts by weight of solid content, when no color is formed in combination with the hue of the base (the dichroic coating film has a base hiding property: when the object to be coated is an automobile or a car body, it is called two coats and one bake) Has a solid content of 0.5 to 20 parts by weight.

The flake pigment which is used in the present invention (2) aluminum flake or MIO as a base material, the base material is coated with silicon dioxide and the outer layer is coated with a metal oxide, (3) brilliant pigment or colored pigment The weight mixing ratio when used in combination with at least one pigment selected from (2) / (3)
= 99/1 to 40/60, more preferably 9
0/10 to 50/50. The weight mixing ratio of the brilliant pigment / colored pigment is preferably from 99/1 to 1/99, and the pigments can be combined so as to have a desired color tone in this range.

"Solvent" The dichroic 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 dichroic coating composition of the present invention comprises, in addition to the above essential components, an extender pigment, an antisettling agent, a curing catalyst, an ultraviolet absorber, an antioxidant, a leveling agent, silicone And a surface conditioner such as an organic polymer, an anti-sagging agent, a thickener, an antifoaming 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 the anti-settling agent, a polyamide wax which is a lubricating dispersion of an aliphatic amide and a polyethylene wax which is a colloidal dispersion mainly composed of polyethylene oxide are preferable.

The first method of forming a dichroic coating film of the present invention is characterized in that after forming a base coat film with the above-described dichroic coating composition of the present invention, a top coat coating film with a clear coating is formed. A method of forming a dichroic coating film, wherein the base coat contains (2) aluminum flake or MIO as a base material, the base material is coated with silicon dioxide, and the outer layer is coated with a metal oxide, and the flake pigment is contained. Providing system (I).

The second method of forming a dichroic coating film of the present invention is characterized in that after forming a base coat film with the dichroic coating composition of the present invention, a top coat film is formed with a clear coating. And a flake pigment in which a base coat is made of aluminum flake or MIO as a base material, the base material is coated with silicon dioxide, and the outer layer is coated with a metal oxide, and (3) brilliancy. An object of the present invention is to provide a coating system (II) containing at least one kind of pigment selected from a functional pigment and a coloring pigment.

"Coated object (substrate)" The object to be coated (substrate) of the dichroic paint composition and the dichroic coating film forming method of the present invention is iron, aluminum, copper or the like. 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 Resins such as resins and plastic materials such as various FRPs; natural and synthetic materials such as wood and fiber materials (paper, cloth, etc.).

[0030] The coating composition is applied to the substrate to be coated directly or through an undercoating 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 or the like in advance. preferable.

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

<Base coat: dichroic coating> In the case of using a substrate coated with an undercoat with an intermediate coating or the like,
A dichroic paint composition is applied on the base coat 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 undercoat film is formed and then dried by air drying or the like, and then applied in an uncured state or a semi-cured state. The B / W method is a method in which the undercoat 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 dichroic coating film is preferably 5 to 50 μm,
0 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 10 to 80 μm, and 20 to 50 μm
Is more preferred.

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. After the agent is blown off, a high pressure mercury lamp, a metal halide lamp, a xenon lamp or the like is irradiated for 0.01 second to 1 minute to cure.

[0035]

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 19, Comparative Examples 1 to 4] 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. Next, after baking at 160 ° C. for 30 minutes, in the coating method 2 coats 1 bake method (2C1B), the intermediate coat (“Olga S-90 Sealer Gray (L =
60) "manufactured by Nippon Paint Co., Ltd., and the intermediate coating (" Olga S-90 Sealer Gray (L = 20) or (L = 6) "in the three-coat two-bake method (3C2B).
0) ", manufactured by Nippon Paint Co., Ltd.)
And sprayed at 140 ° C. for 30 minutes to form an intermediate coating film.

2. Preparation of dichroic 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 melamine resin (trade name, “Uban 20SE”, manufactured by Mitsui Chemicals, Inc., solid content 60% by weight) was mixed at a solid content weight ratio of 80:20, and (A) aluminum flake or Flake pigment ("flake A": diiron trioxide (outermost layer) / silicon dioxide / aluminum flake (base material) in which MIO is used as a base material and the base material is coated with silicon dioxide and the outer layer is coated with a metal oxide Pigment, color: gold / beige, "flake B": diiron trioxide (outermost layer) / silicon dioxide / aluminum flake (substrate) pigment, color: red / gold, "flake C": diiron trioxide (most Outer layer) / silicon dioxide / MIO (base material) pigment, coloring: magenta / kappa), (B) brilliant pigment, and (C) coloring pigment were blended in the proportions shown in Table 1. Subsequently, an organic solvent (weight ratio of toluene / xylene / ethyl acetate / butyl acetate = 70/15/1)
0/5) with a dissolver to stir and mix to obtain a coating proper viscosity to prepare a dichroic coating composition. (B) The glitter pigment is aluminum flake pigment (“Aluminum Paste MH8801”, Asahi Kasei Kogyo Co., Ltd.)
), Colored aluminum flake pigment ("Friend Color F5
00BL ", manufactured by Showa Denko KK, colored mica pigment (" Iriodin 502WII ", manufactured by Merck), interference mica pigment (" Iriodin 217WII ", manufactured by Merck), graphite pigment (" Graphtan 7525 ",
Ciba Specialty Chemicals Co., Ltd.), fine particle titanium oxide pigment ("Taipeku TTO-55B", manufactured by Ishihara Sangyo Co., Ltd.), alumina flake pigment A (iron trioxide-coated alumina flake pigment, manufactured by Merck) and alumina flake Pigment B (titanium dioxide coated alumina flake pigment,
Merck).

3. Formation of Dichroic Coating Film The above-mentioned dichroic coating composition was applied on the surface of the substrate to be coated with a dry film thickness of 1%.
The coating was performed so as to have a thickness of 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 dichroism of the obtained coating film was evaluated by the following evaluation method. Table 1 shows the results.
The clear paint free of metal oxide-coated silica flakes used was (1) an acrylic / melamine resin-based clear paint (trade name: "Super Rack 0-130 Clear", manufactured by Nippon Paint Co., Ltd.) or (2) There are two types of clear coatings ("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.

Evaluation Method Dichroism When the test piece after the coating was formed was viewed from directly above (A),
When viewed at an overhead angle of about 15 degrees with respect to the test piece (B), the color of the coating film was visually evaluated. (A), (B)
Are clearly different, and those with calm dichroism are ◎, and those with different colors in (A) and (B) are ○, (A) and (B), respectively. Those that could not be said to have different colors were evaluated as x.

[0040]

[Table 1]

[0041]

As is clear from the results shown in Table 1, the present invention provides a dichroic coating composition capable of obtaining a calm and excellent dichroic coating film, a method for forming a dichroic coating film, and a method for forming a dichroic coating film. A coated article coated by the method can be provided.

Claims (5)

[Claims] 1. A flake pigment containing (1) a vehicle, (2) aluminum flake or MIO as a base material, the base material coated with silicon dioxide, and the outer layer coated with a metal oxide. A dichroic coating composition. 2. A flake pigment comprising (1) a vehicle, (2) aluminum flake or MIO as a base material, the base material coated with silicon dioxide and the outer layer coated with a metal oxide, and (3) a bright pigment or A dichroic coating composition comprising at least one pigment selected from color pigments. 3. An aluminum flake or MIO according to claim 1 or 2, wherein said substrate is coated with silicon dioxide.
A dichroic coating composition, wherein the flake pigment whose outer layer is coated with a metal oxide is 0.01 to 30 parts by weight of solids per 100 parts by weight of coating solids. 4. A method for forming a dichroic coating film, comprising forming a clear top coat coating film on an object to be coated after forming a base coat film with the dichroic coating composition according to claim 1. 5. A coated article, wherein a coating is formed on the article to be coated according to claim 4 by a dichroic coating film forming method.