Lustrous paint and coated article

Abstract

To provide a lustrous paint that is capable of sufficiently orienting flake-shaped indium used as a flake-shaped metal filler in the process of forming a coating film, and that is capable of forming the coating film having excellent luster.SOLUTION: A lustrous paint comprises a hydrocarbon-based solvent (A) having an aniline point of 40°C or higher; a resin (B1) that is incompatible with the hydrocarbon-based solvent (A); a solvent (C) that is compatible with both the hydrocarbon-based solvent (A) and the resin (B1) and has a lower boiling point than the hydrocarbon-based solvent (A); a flake-shaped metal filler (D); and a siloxane-based surfactant (E), wherein the flake-shaped metal filler (D) is flake-shaped indium (D1).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a glossy paint and a coated article. [Background technology]

[0002] In order to improve the design and luxury of the surfaces of automobile interior and exterior parts and various molded products, thin metal films are sometimes formed on these surfaces. Known methods for forming thin metal films include metal plating and metal vapor deposition, but these methods require plating or vapor deposition equipment. In recent years, therefore, glittering paints containing flake-like metal fillers as glittering pigments have been used because the working process is simple and there are no limitations on the size of the equipment or the object to be coated.

[0003] In order to form a coating film having high brilliance using a glittering paint containing scaly metal filler, it is necessary to orient the scaly metal filler parallel to the coating surface. As a method for orienting the scaly metal filler parallel to the coating surface, a rheology control agent is generally added to the glittering paint, or a leafing type metal filler or a metal flake obtained by crushing a vapor-deposited thin metal film formed by vapor deposition is generally used as the scaly metal filler. In reality, however, the metal filler particles are often irregularly oriented on the coating surface, making it difficult to achieve sufficient luster.

[0004] For example, Patent Document 1 presents a paint that has excellent orientation of flake metal filler and can form a coating film rich in metallic luster, which uses differences in compatibility and boiling point to orient flake aluminum to create a high-brightness coating film. The paint of Patent Document 1 is said to be capable of forming a coating film with excellent luster. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2018-090739 A Summary of the Invention [Problem to be solved by the invention]

[0006] Scaly indium is expected to be a bright pigment that forms coatings with better appearance than scaly aluminum. However, since scaly indium is expensive, it is desirable to form coatings with high brightness with a small amount of indium. To achieve this, it is important to fully orient indium during the coating formation process and to align it thinly within the coating.

[0007] Therefore, the present inventors attempted to make a bright paint having the same composition as that of Patent Document 1, except that flaky indium was used instead of flaky aluminum. However, when flaky indium was used, sufficient orientation could not be achieved as in the case of using flaky aluminum. This is believed to be because flaky indium has a smaller particle size and a larger specific gravity than flaky aluminum. In view of the above circumstances, the present invention aims to provide a shiny coating material that can be sufficiently oriented during the coating film formation process even when flaky indium is used as the flaky metal filler, and can form a coating film with excellent shine. [Means for solving the problem]

[0008] The present invention has the following aspects. [1] A hydrocarbon solvent (A) having an aniline point of 40°C or higher; a resin (B1) that is incompatible with the hydrocarbon solvent (A); a solvent (C) which is compatible with the hydrocarbon solvent (A) and the resin (B1) and has a boiling point lower than that of the hydrocarbon solvent (A); A flake metal filler (D); A siloxane-based surfactant (E); Contains A luster paint, wherein the flaky metal filler (D) is flaky indium (D1). [2] The glittering coating material according to [1], wherein the siloxane-based surfactant (E) is a polyether-modified siloxane-based surfactant (E1). [3] A substrate and a coating film formed on a surface of the substrate, A coated article, wherein the coating film is obtained by coating the glossy paint according to [1] or [2]. Effect of the Invention

[0009] According to the glittering coating material of the present invention, even when flaky indium is used as the flaky metal filler, sufficient orientation can be achieved during the coating film formation process, and a coating film with excellent glittering properties can be formed. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view showing a schematic example of a process for forming a coating film using the glittering coating material of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] In this specification and the claims, when a component is "incompatible" with another component, it is meant that the two components are separated and an interface is formed between the two components. In contrast, when a component is "compatible" with another component, it means that the two components do not separate and no interface is formed between the two components. In this specification and claims, the use of "to" indicating a range of numerical values ​​means that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0012] The glittering paint of the present invention contains the following components (A), (B1), (C), (D) and (E). The glittering paint may contain the following component (B2) and optional components as required. The components (B1) and (B2) are collectively referred to as "component (B)". Component (A): A hydrocarbon solvent with an aniline point of 40°C or higher Component (B1): a resin that is incompatible with component (A) Component (B2): a solvent that dissolves or disperses component (B1) and is incompatible with component (A). Component (C): a solvent that is compatible with components (A) and (B1) and has a lower boiling point than component (A). (D) Component: flake metal filler Component (E): Siloxane-based surfactant

[0013] <Component (A)> Component (A) is a hydrocarbon solvent having an aniline point of 40° C. or higher. If the aniline point is 40°C or higher, the component (A) separates from the component (B) during the coating film formation process, and a layer of the component (A) (hereinafter referred to as "layer A") and a layer of the component (B) (hereinafter referred to as "layer B") are formed, as described in detail below. There is no particular upper limit for the aniline point, but 90°C is preferable. Solvents with high aniline points generally have large molecular weights, and therefore tend to have high boiling points. If the aniline point is 90°C or lower, the component (A) is easily volatilized by heat treatment. The aniline point is a value measured in accordance with JIS K 2256:2013 (ISO 2977:1997). When component (A) contains two or more types of components, the aniline point in the mixed state is sufficient to be 40°C.

[0014] In addition, since component (A) is separated from component (B) during the coating film formation process and then volatilized by heat treatment, almost no component (A) remains in the final coating film. In other words, the coating film formed from the bright paint of the present invention does not substantially contain component (A).

[0015] Examples of the component (A) include aliphatic hydrocarbon solvents and unsaturated hydrocarbon solvents. Aliphatic hydrocarbon solvents include those with the composition formula C na H 2na+2 (where na ≧ 6), paraffins represented by the composition formula C nb H 2nb (where nb≧7) and their alkyl adducts, represented by the formula C nc H 2nc-2Examples of such naphthenes include bicyclic naphthenes represented by the following formula: and their alkyl group adducts.

[0016] Specific examples of such solvents include normal paraffins such as normal hexane, normal heptane, normal octane, normal nonane, and normal decane; isoparaffins such as isooctane, isononane, and isodecane; monocyclic naphthenes such as cycloheptane, methylcyclohexane, ethylcyclohexane, and nonylcyclohexane; and bicyclic naphthenes such as decahydronaphthalene. These may be used alone or in combination of two or more. Examples of the unsaturated hydrocarbon solvent include limonene and diisobutylene. The component (A) may use one type alone, or two or more types in combination.

[0017] The boiling point of component (A) is preferably 80 to 220° C., more preferably 100 to 200° C., and even more preferably 120 to 180° C. When the boiling point of component (A) is within the above range, it is easily volatilized by heat treatment after being separated from component (B) during the coating film formation process.

[0018] The content of the (A) component is preferably 5 to 40 mass %, more preferably 10 to 35 mass %, based on the total mass of the glittering paint. If the content of the (A) component in the glittering paint is too high, the proportion of the (B1) component, which is the main component of the coating film, decreases, and thick coating may be required to obtain a coating film of the desired thickness. In addition, the proportion of the (C) component decreases, and as a result, the (A) component and the (B) component become less compatible, and it may be difficult to obtain a uniform glittering paint. On the other hand, if the content of the (A) component is too low, the interface between the A layer and the B layer tends to be less sufficiently formed during the coating film formation process.

[0019] <(B1) component> The component (B1) is a resin that is incompatible with the component (A). The component (B1) is the main component of the coating film formed from the bright coating material of the present invention.

[0020] It is preferable that the polarity of the (B1) component is higher than that of the (A) component. If the polarity of the (B1) component is higher than that of the (A) component, when it is separated from the (A) component during the coating film formation process, the B layer, which has a higher polarity and a higher surface tension, will be located lower (closer to the substrate) than the A layer, which has a lower polarity and a lower surface tension, and thus the (A) component will be more likely to volatilize by heat treatment.

[0021] As the component (B1), from the viewpoint of easily increasing polarity, a resin having a functional group (polar group) such as a hydroxyl group or a carbonyl group or a large number of ether bonds in the molecule is preferable. In particular, a resin having a hydroxyl group is preferable. Examples of such a resin include polycarbonate diol and polyester polyol.

[0022] Examples of polycarbonate diols include those obtained by reacting a diol (e.g., ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, neopentyl glycol, etc.) with a carbonate (e.g., dimethyl carbonate, diphenyl carbonate, ethylene carbonate, phosgene, etc.).

[0023] Examples of polyester polyols include those obtained by reacting dicarboxylic acids (e.g., phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, adipic acid, sebacic acid, etc.) with polyhydric alcohols (e.g., ethylene glycol, propylene glycol, tetramethylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, trimethylolpropane, pentaerythritol, etc.); polycaprolactone oligomers, etc.

[0024] When the component (B1) contains a resin having a hydroxyl group, such as the above-mentioned polycarbonate diol or polyester polyol, the component (B1) may further contain a curing agent that reacts with the resin to cure it. Examples of the curing agent for the resin having a hydroxyl group include polyisocyanate compounds and melamine resins.

[0025] Examples of polyisocyanate compounds include pentamethylene diisocyanate, hexamethylene diisocyanate, tolylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, norbornene diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, isocyanurate, biuret, polyhydric alcohol adduct, and modified product by allophanate bond of isocyanurate, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. These may be used alone or in combination of two or more. Examples of the melamine resin include methylated melamine resin, normal butylated melamine resin, and isobutylated melamine resin. The component (B1) may be used alone or in combination of two or more types.

[0026] The content of the (B1) component is preferably 5 to 50% by mass, more preferably 10 to 40% by mass, based on the total mass of the glittering paint. If the content of the (B1) component in the glittering paint is too high, the viscosity of the glittering paint increases, and it tends to be difficult to obtain a smooth coated surface. On the other hand, if the content of the (B1) component is too low, thick coating may be required to obtain a coating film of the desired thickness. If thick coating is applied, it may take a long time to harden, and some of the glittering paint may flow (drip) and accumulate, resulting in a thick coating thickness in some places.

[0027] <(B2) component> The component (B2) is a solvent that dissolves or disperses the component (B1), and is a solvent that, together with the component (B1), forms layer B during the coating film formation process. The component (B2) is not compatible with the component (A). If the viscosity of the paint is low enough that it can be applied without component (B2), then component (B2) need not be used.

[0028] During the coating film formation process, component (B2) volatilizes by heat treatment before or after separation from component (A), so that almost no component (B2) remains in the final coating film. In other words, even if the glittering paint of the present invention contains component (B2), the coating film formed from this glittering paint does not substantially contain component (B2).

[0029] As the component (B2), from the viewpoint of easily increasing polarity, a solvent having a functional group (polar group) such as a keto group, a hydroxy group, or a carbonyl group in the molecule, an element having an unshared electron pair such as nitrogen or sulfur, or an ether bond is preferable. Examples of such a solvent include cyclic carbonate solvents, polyhydric alcohols, ketone solvents, and aprotic polar solvents containing nitrogen or sulfur elements. These may be used alone or in combination of two or more.

[0030] Examples of the cyclic carbonate solvent include ethylene carbonate, propylene carbonate, etc. These may be used alone or in combination of two or more. Examples of polyhydric alcohols include ethylene glycol, propylene glycol, 1,2-butanediol, tetramethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, trimethylolpropane, pentaerythritol, etc. These may be used alone or in combination of two or more.

[0031] Examples of the ketone solvent include diacetone alcohol, isophorone, etc. These may be used alone or in combination of two or more. Examples of the aprotic polar solvent containing a nitrogen element or a sulfur element include N,N-dimethylformamide, 1,3-dimethyl-2-imidazolidinone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, etc. These may be used alone or in combination of two or more.

[0032] The boiling point of component (B2) may be higher or lower than the boiling point of component (A); however, since it is desirable for component (B2) to volatilize preferentially from the upper A layer by heat treatment after components (A) and (B) are separated during the coating film formation process, it is preferable for the boiling point of component (B2) to be higher than the boiling point of component (A). The boiling point of the component (B2) is preferably from 150 to 300°C, and more preferably from 180 to 250°C.

[0033] The content of the (B2) component is preferably 20% by mass or less, more preferably 0 to 10% by mass, based on the total mass of the glittering paint. If the content of the (B2) component in the glittering paint is too high, the proportion of the (B1) component, which is the main component of the coating film, decreases, and thick coating may be required to obtain a coating film of the desired thickness.

[0034] <(C) component> The component (C) is a solvent that is compatible with the components (A) and (B1) and has a boiling point lower than that of the component (A). When the glittering coating material contains the component (B2), it is preferable that the component (C) is also compatible with the component (B2).

[0035] Since component (C) volatilizes during the coating film formation process, very little of it remains in the final coating film, i.e., the coating film formed from the bright coating material of the present invention does not substantially contain component (C). Examples of the component (C) include ketone-based solvents, alcohol-based solvents, ether-based solvents, ester-based solvents, glycol ether-based solvents, chain carbonate-based solvents, etc. These may be used alone or in combination of two or more.

[0036] Examples of the ketone solvent include acetone, methyl ethyl ketone, diethyl ketone, methyl propyl ketone, methyl isobutyl ketone, etc. These may be used alone or in combination of two or more. Examples of the alcohol-based solvent include methanol, ethanol, normal propanol, isopropanol, normal butanol, isobutanol, 2-butanol, etc. These may be used alone or in combination of two or more kinds.

[0037] Examples of the ether solvent include diethyl ether, diisopropyl ether, methyl isobutyl ether, tetrahydrofuran, cyclopentyl methyl ether, etc. These may be used alone or in combination of two or more. Examples of ester-based solvents include methyl acetate, ethyl acetate, normal propyl acetate, isopropyl acetate, normal butyl acetate, isobutyl acetate, secondary butyl acetate, methyl propionate, ethyl propionate, normal propyl propionate, methyl-2-methylbutyrate, etc. These may be used alone or in combination of two or more.

[0038] Examples of glycol ether solvents include ethylene glycol monomethyl ether, propylene glycol monomethyl ether, monoglyme, etc. These may be used alone or in combination of two or more. Examples of the chain carbonate solvent include dimethyl carbonate, ethyl methyl carbonate, etc. These may be used alone or in combination of two or more.

[0039] The boiling point of the (C) component is lower than that of the (A) component. When the glittering paint contains the (B2) component, the boiling point of the (C) component may be lower or higher than that of the (B2) component, but is preferably lower. The boiling point of component (C) is preferably no greater than 125° C., more preferably from 50 to 100° C. If the boiling point of component (C) is no greater than 125° C., it is prone to volatilization during the coating film formation process.

[0040] The content of the (C) component is preferably 10 to 80% by mass, more preferably 20 to 60% by mass, based on the total mass of the glittering paint. If the content of the (C) component in the glittering paint is too high, the proportion of the (B1) component, which is the main component of the coating film, decreases, and thick coating may be required to obtain a coating film of the desired thickness. On the other hand, if the content of the (C) component is too low, an interface may occur between the (A) component containing the (C) component and the (B) component containing the (C) component, forming a layer, which may make it difficult to apply the coating uniformly.

[0041] <(D) component> Component (D) is a flaky metal filler that imparts luster to the coating film obtained from the luster paint. Examples of flake-like metal fillers include flake-like indium (D1) and flake-like aluminum. However, flake-like indium (D1) is suitable for application in the present invention because it is difficult to orient during the coating film formation process and is expensive, so a coating film with high brilliance must be formed with a small amount of flake-like indium (D1).

[0042] In the present invention, the term "flake-like" refers to a metal filler having an aspect ratio (average particle diameter / thickness), which is the ratio of the average particle diameter to the thickness thereof, of 2 to 1,000. Moreover, the "average particle size" refers to the 50% particle size (D50%) measured by a laser diffraction scattering method (Microtrack method).

[0043] The thickness of component (D) is preferably 0.005 to 2 μm, more preferably 0.01 to 0.1 μm. Component (D) having a thickness of 0.005 μm or more is easy to manufacture and is not easily see-through, so that the gloss of the coating film is increased. On the other hand, if the thickness of component (D) is 2 μm or less, the appearance of the coating film can be maintained good. In particular, if the thickness of component (D) is 0.1 μm or less, a coating film with a more metallic tone can be easily obtained. The thickness of component (D) is measured using an electron microscope.

[0044] The average particle size of component (D) is preferably 0.01 to 10 μm, and more preferably 0.01 to 2 μm. If the average particle size of component (D) is 0.01 μm or more, a thickness of component (D) of 0.01 μm or less is easily obtained. On the other hand, if the average particle size of component (D) is 10 μm or less, a smooth metallic coating film is easily obtained.

[0045] The component (D) may be in the form of a paste dispersed in an organic solvent. The component (D) may be a scaly metal filler whose surface has been treated with a surface treatment agent such as a fatty acid or a silane coupling agent, or which has been coated with a transparent resin. The term "transparent" means that the metallic tone of component (D) is not impaired when the surface of component (D) is covered, and it is preferable that the total light transmittance is 50% or more.

[0046] Examples of component (D) include thin metal films formed by vapor deposition or by rolling, which have been crushed into flakes. Among these, crushed thin metal films formed by vapor deposition are preferred because they tend to give a coating film with a more metallic appearance. The vapor-deposited metal thin film can be obtained, for example, by depositing a metal on a substrate film such as polyethylene terephthalate to form a vapor-deposited metal thin film on the substrate film, and then peeling the film off from the substrate film. The vapor-deposited metal thin film is crushed into irregular shapes to produce scaly metal filler.

[0047] The thin film produced by rolling is crushed into irregular or circular (including elliptical) shapes to produce flake metal filler. The flake-like metal filler crushed into an irregular shape is also called "cornflake-like rolled metal flakes," and the flake-like metal filler crushed into a circular shape is also called "coin-like rolled metal flakes." The coin-like rolled metal flakes have smooth edges and a smooth surface.

[0048] The content of the (D) component is preferably 0.01 to 5 mass % and more preferably 0.1 to 2 mass % based on the total mass of the glittering paint. If the content of the (D) component in the glittering paint is too high, the (D) components tend to overlap with each other, forming a fine uneven shape. If a large number of uneven shapes are formed, light tends to be diffusely reflected. If the content of the (D) component is 10 mass % or less, the formation of a large number of uneven shapes can be suppressed, so that diffuse reflection of light can be prevented and glittering properties can be maintained well. On the other hand, if the content of the (D) component is too low, it becomes difficult to sufficiently conceal the base.

[0049] <(E) component> Component (E) is a siloxane-based surfactant. Siloxane-based surfactants are surfactants whose main skeleton is made up of siloxane bonds, in which silicon (Si) and oxygen (O) are alternately linked by chemical bonds, and whose structure is achieved by introducing a hydrophilic organic group into part of the silicone. The main skeleton of the siloxane bond may be linear, branched, or cyclic.

[0050] Modification methods for introducing organic groups include polyether modification, polyether-alkyl co-modification, polyglycerin modification, and polyether-silicone-alkyl modification, with polyether modification being preferred. When the main skeleton of the siloxane bond is linear, the site where the organic group is introduced by modification may be the side chain, both ends, one end, or the side chain and both ends, but introduction into the side chain is preferred.

[0051] Examples of commercially available polyether-modified siloxane surfactants include BYK (registered trademark)-307, BYK-345, BYK-346, BYK-347, BYK-348, BYK-349 (all manufactured by BYK Co., Ltd.), Silface (registered trademark) SAG002, Silface SAG005, Silface SAG0503A, Silface SAG008 (all manufactured by Nissin Chemical Industry Co., Ltd.). Two or more of these may be contained. Among these, BYK-307, BYK-347, etc. are preferred.

[0052] The content of component (E) is preferably 0.0001 to 0.015% by mass, and more preferably 0.0003 to 0.01% by mass, based on the total mass of the glittering paint. When the content of component (E) in the glittering paint is equal to or greater than the preferred lower limit, a highly glossy coating film can be obtained. When the content is equal to or less than the preferred upper limit, a highly glossy coating film can be obtained without interfering with the orientation of layer D formed at the interface between layers A and B.

[0053] <Optional ingredients> The glittering coating material may contain components (optional components) other than the components (A), (B), (C), (D) and (E) as necessary, provided that the effects of the present invention are not impaired. Examples of optional components include hydrocarbon solvents with an aniline point of less than 40°C (hereinafter also referred to as "other hydrocarbon solvents"), solvents that are compatible with components (A) and (B1) and have a boiling point higher than or equal to that of component (A), and additives.

[0054] Examples of other hydrocarbon solvents include benzene, toluene, xylene, ethylbenzene, isopropylbenzene, normal propylbenzene, ethylmethylbenzene, trimethylbenzene, indane, indene, diethylbenzene, dimethyl-ethylbenzene, tetramethylbenzene, 1-methyl-3-propylbenzene, 1-methyl-2-normal propylbenzene, methylindane, naphthalene, pentane, cyclopentane, cyclohexane, etc. Examples of mixed solvents of other hydrocarbon solvents include mineral spirits, solvent naphtha, etc.

[0055] Examples of solvents that are compatible with the components (A) and (B1) and have a boiling point equal to or higher than that of the component (A) include ketone-based solvents, alcohol-based solvents, ester-based solvents, glycol ether-based solvents, and chain carbonate-based solvents. Examples of the ketone solvent include methyl amyl ketone, cyclohexanone, diisobutyl ketone, and methyl hexyl ketone. Examples of the alcohol solvent include 3-methoxy-3-methyl-1-butanol, 3-methyl-1-pentanol, normal hexanol, and normal heptanol.

[0056] Examples of the ester solvent include amyl acetate, isoamyl acetate, normal hexyl acetate, 3-methoxybutyl acetate, 3-methoxy-3-methyl-1-butyl acetate, ethyl-3-ethoxypropionate, 2-methylpropyl-2-methylpropionate, and ethyl lactate. Examples of glycol ether solvents include diethylene glycol monomethyl ether, ethylene glycol monoisopropyl ether, diethylene glycol monoisopropyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol monoisobutyl ether, dipropylene glycol monomethyl ether, propylene glycol mono-n-propyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, and ethylene glycol monobutyl ether acetate. An example of the chain carbonate solvent is diethyl carbonate.

[0057] Examples of additives include hardening accelerators such as dibutyltin laurate, extender pigments such as calcium carbonate, coloring pigments such as carbon, plasticizers such as dibutyl phthalate, hardening retarders such as phosphate esters, viscosity adjusters such as silica powder, etc. These additives are preferably compatible with component (B1).

[0058] When component (D) is in a paste form, the organic solvent in which component (D) is dispersed is included in either component (A), component (B2), component (C) or optional component, and the organic resin component in which component (D) is dispersed is included in either component (B1) or optional component. When component (D) is a flaky metal filler whose surface has been treated with a surface treatment agent such as a fatty acid or a silane coupling agent, the surface treatment agent is included in the optional component.

[0059] In addition, it is preferable that the glittering coating material does not substantially contain a resin that is compatible with the component (A) (hereinafter, this may also be referred to as "another component that is compatible with the component (A)"). Among the other components compatible with the component (A), examples of resins include low-polarity acrylic resins. Here, "substantially free" means that the content of other components that are compatible with component (A) is less than 0.1% by mass relative to the total mass of the glittering coating material.

[0060] <Formation of coating film> An example of the process in which a coating film is formed on the surface of a substrate using the brilliant coating material of the present invention and a coated article is obtained will be described with reference to FIG. In the following description, the glittering paint also includes component (B2).

[0061] First, the glittering paint 10 of the present invention is applied onto a substrate 20 (step (a)). The method for applying the glittering paint 10 is not particularly limited, and any known application method such as brush, trowel, roller, spray, flow coating, dipping coating, shower coating, printing, etc. can be used.

[0062] The glittering coating 10 immediately after being applied to the substrate 20 contains components (A), (B), (C), (D) 13, and (E). Components (A) and (B) are compatible with component (C). Component (D) is randomly dispersed in the compatible components (A) and (B). Component (E) is also randomly dispersed in the compatible components (A) and (B).

[0063] The substrate 20 may be a metal substrate, a plastic substrate, or the like. Examples of materials for the metal substrate include aluminum, iron, nickel, chromium, titanium, copper, silver, zinc, tin, indium, magnesium, oxides of these metals, and alloys of these metals. On the other hand, examples of materials for the plastic substrate include polyester (e.g., polyethylene terephthalate, polybutylene terephthalate, etc.), polyolefin (e.g., polyethylene, polypropylene, etc.), polycarbonate, acrylonitrile-butadiene-styrene copolymer resin (ABS), acrylic resin, acrylonitrile-styrene copolymer resin, acrylic-styrene copolymer resin, polyvinyl chloride resin, etc.

[0064] Next, the glittering coating material 10 on the substrate 20 is naturally dried or heat-treated (step (b)). Since component (C) has a lower boiling point than component (A), when the glittering paint 10 is naturally dried or heat-treated, component (C) in the glittering paint 10 volatilizes before component (A). At this time, if the boiling point of component (B2) is lower than that of component (C), component (B2) will volatilize along with component (C), and if the boiling point of component (B2) is higher than that of component (C), only component (C) will volatilize. When the glittering coating material 10 is heat-treated in step (b), the heating temperature is preferably higher than the boiling point of component (C) and lower than the boiling point of component (A).

[0065] Since the component (A) is a hydrocarbon solvent with an aniline point of 40° C. or higher, and the component (B) is a resin that is not compatible with the component (A), when the component (C) volatilizes, the components (A) and (B) separate, forming a layer (A layer) 11 of the component (A) and a layer (B layer) 12 of the component (B). If the polarity of the component (B1) is higher than that of the component (A), the layer (B) 12 is located below the layer (A) 11, as shown in FIG. 1. In addition, the component (B) attached to the surface of the substrate 20 has a higher surface tension than the component (A), and the components (B) attract each other and act to form the layer (B) 12. As a result, it is considered that the layer (A) 11 is formed so as to cover the surface of the layer (B) opposite to the surface in contact with the substrate 20 (the gas phase side) of the layer (B) 12, with the component (A) being expelled from the layer (B) 12. Therefore, even if the substrate 20 is set up vertically or a substrate 20 having a vertical portion is coated, the layer B 12 is formed on the substrate 20 and the layer A 11 is formed on this layer B 12 .

[0066] Normally, when a powder is added to multiple liquid phases that are not compatible with each other, the powder disperses or precipitates in each liquid phase, but component (D) has an affinity for components (A) and (B). Therefore, when components (A) and (B) are separated in step (b) and layer A 11 and layer B 12 are formed, component (D) 13 is adsorbed to the interface between layer A 11 and layer B 12 like a surfactant, and component (D) 13 is localized at the interface between layer A 11 and layer B 12. At this time, there is variation in the orientation of component (D).

[0067] In addition, at the stage where step (b) is performed, if the boiling point of the (B2) component is lower than that of the (C) component, the B layer 12 contains the (B1) component but not the (B2) component, and if the boiling point of the (B2) component is higher than that of the (C) component, the B layer 12 contains the (B1) component and the (B2) component. In addition, if the glittering paint contains an additive that is compatible with the (B1) component, the B layer 12 also contains the additive in addition to the (B) component. In the case where the glittering paint contains other hydrocarbon-based solvents, a part of the other hydrocarbon-based solvent is compatible with the (B) component and is contained in the B layer 12. The remaining other hydrocarbon-based solvents that exceed the saturation amount of the (B) component (not compatible with the (B) component) are contained in the A layer 11.

[0068] Next, the A layer 11 and the B layer 12 are naturally dried or heat treated (step (c)). The (A) component volatilizes in step (c). If the A layer 11 contains other hydrocarbon solvents, the other hydrocarbon solvents also volatilize in step (c). If the B layer 12 contains the (B2) component or other hydrocarbon solvents, the (B2) component and other hydrocarbon solvents also volatilize in step (c). As a result, the A layer 11 disappears, and the B layer 12 remains on the substrate 20. After step (c), the B layer 12 contains the (B1) component and, if necessary, additives, and the (B2) component has been largely removed.

[0069] Furthermore, as component (A) volatilizes, layer A 11 becomes thinner and eventually disappears, but in the process, component (D) 13 is oriented parallel to the surface of layer B 12, and a smooth film made of component (D) 13 is formed on the surface of layer B 12. In this way, a glossy coating film 30 comprising layer B 12 and a smooth film made of component (D) 13 formed on the surface of layer B 12 is formed on substrate 20, and a coated article is obtained.

[0070] The heating temperature in the heat treatment in step (c) is preferably higher than the boiling point of component (A). When the boiling point of the (B2) component is higher than that of the (A) component, the heating temperature in step (c) is preferably higher than that of the (B2) component. The heating temperature in step (c) may be increased stepwise. For example, the mixture may be heated at a temperature higher than the boiling point of the (A) component and lower than the boiling point of the (B2) component, and then further heated at a temperature higher than the boiling point of the (B2) component.

[0071] Since the (D) component 13 on the surface of the B layer 12 is easily scratched or deteriorated by external factors, it is preferable to apply a clear paint to the surface of the glossy coating film 30 (the side opposite the substrate 20) to form a clear coating film.

[0072] <Action and effect> In the glittering paint of the present invention, the (A) and (B) components are compatible with the (C) component, the (D) component is dispersed in the paint, and the (E) component is dispersed in the paint, but as described above, in the process of forming the coating film, the (C) component first volatilizes and the (A) and (B) components separate. At this time, the (D) component is localized to a certain extent at the interface between the A layer and the B layer. Next, as the (A) component volatilizes, the (D) component is oriented on the surface of the B layer almost completely parallel to the surface, and a film of the (D) component is formed on the surface of the B layer.

[0073] It is not clear why the presence of component (E) ensures sufficient orientation even when component (D) is scaly indium (D1). However, it is speculated that this is because layer B becomes smooth during step (b), which makes it easier for component (D) to be leveled and oriented in parallel. In this way, excellent brilliance can be exhibited because the component (D) is oriented parallel to the surface of the layer B. Therefore, according to the brilliance coating material of the present invention, even if the component (D) is scaly indium (D1), a coating film (brilliant coating film) with excellent brilliance can be formed.

[0074] As described above, component (D) has affinity for components (A) and (B), so when components (A) and (B) separate, it is believed that component (D) localizes at the interface between layer A and layer B. When a luster pigment other than component (D) (such as a pearlescent pigment) is used, localization of the luster pigment at the interface between layer A and layer B is unlikely to occur.

[0075] In addition, in order for the coating film to exhibit sufficient luster, it is necessary that the (D) component is oriented parallel to the surface of the coating film. In the present invention, after the (A) component and the (B) component are separated and the (D) component is localized at the interface between the A layer and the B layer, when the (A) component volatilizes and the A layer disappears, the (D) component is oriented parallel to the surface of the B layer. When the (A) component volatilizes and the A layer disappears, the (D) component is more likely to be oriented parallel to the surface of the B layer if no components other than the (D) component remain on the B layer. In order to prevent components other than the (D) component from remaining on the B layer, as described above, it is preferable that the luster paint does not substantially contain other components compatible with the (A) component. EXAMPLES

[0076] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these. The raw materials used in the examples and comparative examples are as follows.

[0077] "Raw materials used" <Component (A)> ·A-1: Methylcyclohexane (aniline point: 40℃, boiling point: 101℃). ·A-2: Ethylcyclohexane (aniline point: 43℃, boiling point: 132℃). A-3: Aliphatic petroleum hydrocarbon (manufactured by ExxonMobil Corporation, "Exxsol (registered trademark) DSP 145 / 160", aniline point: 66°C, boiling point: 146 to 158°C). A-4: Mixture of aliphatic petroleum hydrocarbons and aromatic petroleum hydrocarbons (manufactured by TonenGeneral Sekiyu K.K., "T-SOL (registered trademark) 3040 FLUID", aniline point: 52°C, boiling point: 159 to 187°C). A-5: Aliphatic petroleum hydrocarbon (manufactured by ExxonMobil Corporation, "Isopar (registered trademark) G", aniline point: 83°C, boiling point: 166 to 176°C).

[0078] <(AX) component> ·AX-1: Xylene (aniline point: 28°C, boiling point: 144°C). · AX-2: Aromatic petroleum hydrocarbon (manufactured by Idemitsu Kosan Co., Ltd., "IPZOL (registered trademark) 100", aniline point: less than 0°C, boiling point: 159 to 172°C).

[0079] <(B1) component> B1-1: Polycarbonate diol (manufactured by Asahi Kasei Corporation, "DURANOL (registered trademark) T5651"). B1-2: Isocyanurate type hexamethylene diisocyanate (manufactured by Asahi Kasei Corporation, "Duranate TPA-100"). · B1-3: Polycaprolactone diol (manufactured by Daicel Corporation, "Placcel (registered trademark) 210"). B1-3 is a polyester polyol. Incidentally, B1-1, B1-2 and B1-3 are resins that are incompatible with the above-mentioned A-2 to A-5.

[0080] <(B1X) Ingredients> B1X-1: Acrylic polyol (manufactured by Toagosei Co., Ltd., "ARUFON (registered trademark) UH-2041"). Incidentally, B1X-1 is a resin that is compatible with the above-mentioned A-4.

[0081] <(B2) component> ·B2-1: Propylene carbonate (boiling point: 240℃). ·B2-2: Propylene glycol (boiling point: 188℃). ·B2-3: 1,4-butanediol (boiling point: 230℃). It should be noted that B2-1, B2-2 and B2-3 are solvents that are compatible with the above-mentioned B-1 to B-3 but are incompatible with the above-mentioned A-1 to A-5.

[0082] <(B2X) component> · B2X-1: diethylene glycol monoethyl ether acetate (boiling point: 217°C). Note that B2X-1 is a solvent that is compatible with the above B-1 and B-2.

[0083] <(C) component> · C-1: Acetone (boiling point: 56℃). <(CX) component> · CX-1: Propylene glycol monoethyl ether (boiling point: 133°C).

[0084] <(D) component> D-1: Vapor-deposited indium flakes (manufactured by Oike Kogyo Co., Ltd., "Leaf Powder (registered trademark) 49CJ-1120", average particle size: 1 μm, thickness: 0.1 μm, aspect ratio (average particle size / thickness) 10:, non-volatile content: 20% by mass).

[0085] <(DX) components> DX-1: Pearl mica (Merck, "Iriogin 111 WNT").

[0086] <(E) component> E-1: Polyether-modified siloxane surfactant (BYK's "BYK-307"). E-2: Polyether-modified siloxane surfactant (BYK's "BYK-347"). E-3: Polyether modified siloxane surfactant ("SAG005" manufactured by Nissin Chemical Co., Ltd.). E-4: Polyester modified siloxane surfactant (BYK's "BYK-313").

[0087] <(EX) component> EX-1: Acrylic surfactant (BYK's "BYK-350"). EX-2: Acrylic surfactant (BYK's "BYK-392").

[0088] <Optional ingredients> ·DBTDL: Dibutyltin dilaurate. DBTDL is an additive that is incompatible with component (A).

[0089] "Examples 1 to 15, Comparative Examples 1 to 13" Each component was mixed based on the composition shown in Tables 1 to 4 to prepare a glittering paint. A blank cell in Tables 1 to 4 indicates that the component was not mixed. In Tables 1 to 4, the amount of component (D) is the amount of non-volatile matter (i.e., evaporated indium flakes or pearl mica). Also, "derived from (D)" is the volatile matter (corresponding to component (C) or optional component) contained in component (D) or component (DX). In addition, in Tables 1 to 4, the blending amount of component (E) is the amount of non-volatile matter. Also, "derived from (E)" is the volatile matter (corresponding to component (C) or optional component) contained in component (E) or component (EX).

[0090] A glittering paint was applied to an acrylonitrile-butadiene-styrene resin plate (ABS plate) using a spray so that the film thickness after step (c) would be 20 μm (step (a)).The glittering paint on the ABS plate was then dried for 10 minutes at a temperature of 23°C and a humidity of 50% RH (step (b)), and then further dried for 1 hour at a temperature of 80°C (step (c)), forming a coating film. The resulting coating films were evaluated for brilliance as follows, and the results are shown in Tables 1 to 4.

[0091] <Evaluation of brilliance> (Appearance evaluation) The appearance of the formed coating film was visually observed and evaluated according to the following criteria. ◎: Both close-up and distant views are clearly reflected. ○: The close-up view is clearly visible, but the distant view is slightly blurred. △: The near view is clearly visible, but the distant view is blurred. ×: The foreground is blurred.

[0092] (Gloss measurement) The 20° gloss of the formed coating film was measured using a specular gloss meter (BYK-Gardner's "Micro-Tri-Gloss μ") in accordance with JIS Z 8741. A higher gloss value indicates a higher gloss (more lustrous).

[0093] [Table 1]

[0094] [Table 2]

[0095] [Table 3]

[0096] [Table 4]

[0097] As is clear from Tables 1 and 2, the coating films formed from the glittering paints obtained in each Example had excellent glittering properties. On the other hand, as is clear from Tables 3 and 4, in the case of Comparative Examples 1 to 3 which did not contain the component (E), the component (D) was not uniformly oriented at the interface between the layers A and B, and cracks occurred in the areas where a large amount of the component (D) had accumulated at the edges of the coating film.

[0098] In the case of Comparative Examples 4 and 5, in which AX-1 or AX-2, which has an aniline point of less than 40° C., was used, the components (A) and (B) did not separate, so the interface between the A layer and the B layer was not sufficiently formed, and the component (D) was not localized. In the case of Comparative Example 6, in which B1X-1, which is compatible with the component (A), was used, the components (A) and (B) did not separate, so the interface between the A layer and the B layer was not sufficiently formed, and the (D) component was not localized.

[0099] In the cases of Comparative Examples 7 and 8, which did not contain the component (A), no interface was formed between the layers A and B, and the component (D) was not localized. In the case of Comparative Example 9, in which CX-1, which has a boiling point higher than that of component (A), was used, components (A) and (B) did not separate, and therefore the interface between layer A and layer B was not sufficiently formed, and component (D) was not localized.

[0100] In the case of Comparative Example 11 in which DX-1, a pearl pigment, was used, although an interface was formed between layer A and layer B, DX-1 was not localized at this interface. Therefore, the coating films formed from the glittering paints obtained in Comparative Examples 1 to 9 and 11 were inferior in glittering properties. In the case of Comparative Example 10 in which component (C) was not used, components (A) and (B) separated in the paint, making it impossible to apply the paint. [Explanation of symbols]

[0101] 10 Bright paint 11 A layer 12 B layer 13 (D) Component 20 Base material 30 Bright coating film

Claims

1. A hydrocarbon solvent (A) having an aniline point of 40° C. or higher; A resin (B1) that is incompatible with the hydrocarbon solvent (A); a solvent (C) that is compatible with the hydrocarbon solvent (A) and the resin (B1) and has a boiling point lower than that of the hydrocarbon solvent (A); A flake metal filler (D); A siloxane-based surfactant (E); Contains The lustrous coating material, wherein the flaky metal filler (D) is flaky indium (D1).

2. The glittering coating material according to claim 1, wherein the siloxane-based surfactant (E) is a polyether-modified siloxane-based surfactant (E1).

3. A substrate and a coating film formed on a surface of the substrate, A coated article, wherein the coating film is obtained by coating the glittering paint according to claim 1 or 2.

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