JP5759764B2 - Colored metal pigment and method for producing the same - Google Patents

Description

  The present invention relates to a colored metal pigment used for metallic paint finishing of automobiles and the like, decorative decoration of plastic, printing ink and the like. In particular, the present invention relates to a colored metal pigment having excellent water resistance used in water-based paints or water-based inks. Furthermore, it is related also with the coating composition formed by mix | blending the coloring metal pigment.

  Colored metal pigments made by attaching colored pigments to metal pigments such as aluminum pigments have excellent performance in terms of providing a vivid color tone and good concealment of the base color. Application to decoration, printing ink, etc. is under consideration.

  For example, Japanese Patent Application Laid-Open No. 58-141248 (Patent Document 1) discloses a colored metallic pigment in which a colored pigment is uniformly attached to the surface of the metallic pigment by a polymer composed of a monomer having a polymerizable double bond. Japanese Patent No. 508424 (Patent Document 2) discloses a colored pigment comprising a combination of a flake which is a metal in particular and a polymer matrix which is held thereon and encapsulates a solid colored metal pigment, Japanese Patent Application Laid-Open No. 01-315470. In the publication (Patent Document 3), a carboxylic acid having one or more double bonds and two or more carboxyl groups obtained by thermally polymerizing one or more carboxylic acids having a double bond on the surface of the metallic pigment. In Japanese Patent Laid-Open No. 09-040885 (Patent Document 4), a colored metallic pigment obtained by chemically adsorbing a colored pigment via a pigment A surface-treated colored pigment obtained by coating 0.2 to 100 parts by weight of a monobasic aromatic carboxylic acid on the surface of a colored pigment, Japanese Patent Application Laid-Open No. 09-059532 (Patent Document 5) includes: In a colored metal flake pigment having a vapor-deposited layer of an organic coloring pigment on its surface, Japanese Patent Application Laid-Open No. 09-124973 (Patent Document 6), two in a molecule of 0.2 to 100 parts by weight with respect to 100 parts by weight of the coloring pigment. A surface-treated colored pigment characterized by coating the surface of a colored pigment with an amino compound having the amino group and having no carboxyl group has been proposed.

  Further, in Japanese Patent Application Laid-Open No. 2006-199920 (Patent Document 7) and Japanese Patent Application Laid-Open No. 2005-264144 (Patent Document 8), a metal hydrated oxide layer is formed on the surface, and iron oxide or the like is further formed thereon. A highly corrosion resistant metallic luster interference coloring pigment provided with a second metal hydrated oxide layer is disclosed.

  In addition, International Publication No. 2006/090431 pamphlet (Patent Document 9) describes coloration in which a color pigment is attached on a metal pigment to which a metal oxide is attached in order to reduce the reflectance in the wavelength region of 300 to 600 nm. Metal pigments are disclosed.

JP 58-141248 A JP 05-508424 gazette Japanese Patent Laid-Open No. 01-315470 JP 09-040885 A JP 09-059532 A JP 09-124973 A JP 2006-199920 A JP 2005-264144 A International Publication No. 2006/090431 Pamphlet

  The colored metal pigments as proposed in the above-mentioned Patent Documents 1 to 6 fix the colored pigment by attaching the colored pigment directly to the surface of the metal pigment or via a specific compound and coating the resin thereon. Therefore, the resin that functions as a water-resistant protective film is likely to be defective, and the water resistance is insufficient. In particular, the colored metal pigment of Patent Document 3 has a structure in which the colored pigment is chemically adsorbed after the thermally polymerized polymer resin is formed on the surface of the metallic pigment (metal pigment). Can be expected to improve water resistance to some extent compared to other patent documents, but it is difficult to form a dense film with a thermally polymerized polymer resin. there were. For this reason, even if the colored metal pigment according to Patent Document 3 is used, the metal pigment that is the base of the colored metal pigment is water when used in water-based paints or water-based inks that are increasing in recent environmental measures. There was a problem that hydrogen gas was generated by reacting with.

  On the other hand, colored metal pigments as proposed in Patent Documents 7 to 8 are stable in water-based paints or water-based inks, but the color development is due to the light interference action in each layer. Compared to the case where the colored metal pigments proposed in Patent Documents 1 to 6 are used, there is a problem that a vivid color tone is not obtained and the hue is further limited.

  Further, the colored metal pigment as proposed in Patent Document 9 is intended to prevent deterioration of the colored pigment due to light reflected from the surface of the metal pigment due to light. It did not provide a means to contribute to the improvement of sex.

  The present invention has been made in view of the above situation, and an object of the present invention is to provide a colored metal pigment excellent in water resistance and stable color development and a method for producing the same.

  As a result of various studies on the above problems, the present inventors have formed a dense and excellent water-resistant film on the surface of the metal pigment in advance, and then attached a colored pigment, whereby coloring with excellent water resistance and stable color development. The present inventors have found that a metal pigment can be obtained and completed the present invention.

  That is, the colored metal pigment of the present invention includes a metal pigment, a first coating layer formed on the surface of the metal pigment, and a color pigment attached to the surface of the first coating layer. The layer is composed of a radical polymerizable resin or a first compound, and the first compound is an oxide or water of at least one element selected from the group consisting of Al, Si, Ti, Cr, Zr, Mo, and Ce. It is an oxide.

  Here, the colored pigment is preferably attached to the surface of the organic phosphate compound layer formed on the first coating layer, and the organic phosphate compound layer has at least one polymerizable double bond. It is preferable that it is comprised with the organic phosphoric acid compound which has.

  In the colored metal pigment of the present invention, it is preferable that a second coating layer is further formed on the colored pigment, and the metal pigment is preferably an aluminum pigment.

  The radical polymerizable resin is preferably obtained by radical polymerization of a monomer and / or oligomer having at least one polymerizable double bond, and the first compound includes silicon oxide and / or polysiloxane. The condensate is preferable. Moreover, it is preferable that the said 2nd coating layer is comprised with radically polymerizable resin.

  Furthermore, the present invention provides a first step of preparing a coated metal pigment having a first coating layer formed on the surface of the metal pigment, and a second step of attaching a colored pigment to the surface of the first coating layer of the coated metal pigment. The first coating layer is composed of a radical polymerizable resin or a first compound, and the first compound is at least selected from the group consisting of Al, Si, Ti, Cr, Zr, Mo, and Ce. The present invention also relates to a method for producing a colored metal pigment which is an oxide or hydroxide of one element.

  Here, the manufacturing method includes, after the first step, an additional step of forming an organic phosphate compound layer by adsorbing an organic phosphate compound on the surface of the first coating layer of the coated metal pigment. In the step, a color pigment can be attached on the organic phosphoric acid compound layer formed in the adding step.

  Moreover, this invention relates also to the coating composition formed by mix | blending said colored metal pigment.

  Since the colored metal pigment of the present invention has the above-described configuration, it is excellent in water resistance, so it is sufficiently stable in a water-based paint or water-based ink and does not cause a problem of gas generation, and a stable color development is obtained. Highly saturated design can be obtained.

Hereinafter, the present invention will be described in more detail with reference to embodiments.
<Colored metal pigment>
The colored metal pigment of the present invention has a basic structure that includes a metal pigment, a first coating layer formed on the surface of the metal pigment, and a color pigment attached to the surface of the first coating layer. Hereinafter, each component will be described in more detail.

<Metal pigment>
As the metal pigment constituting the colored metal pigment of the present invention, any conventionally known metal pigment can be used as long as it exhibits a metallic feeling, and is not particularly limited. Examples of such metal pigments include metal pigments composed of metals such as aluminum, zinc, copper, iron, bronze, nickel, titanium, and stainless steel, and metal pigments composed of alloys containing these metals. .

  Among these metal pigments, aluminum pigments made of aluminum are particularly suitable because they are highly reflective and excellent in metallic luster, are inexpensive and easy to handle because of their low specific gravity. In addition, in such a metal pigment, particles that have a metallic feeling by forming a metal film on the surface of inorganic compound particles (glass, mica, ceramic particles such as alumina or titania) by plating or the like. Is also included.

  Hereinafter, an aluminum pigment particularly suitable as such a metal pigment will be described. Here, as a composition of the aluminum pigment used for this invention, it may be comprised only from aluminum, and may be comprised from the aluminum base alloy, The purity of aluminum is not specifically limited.

  Moreover, the shape of the aluminum pigment used for this invention can use the thing of various shapes, such as granular form, plate shape, block shape, flake shape (flaky shape), but gives the metallic feeling and brightness | luminance which were excellent in the coating film. For this purpose, a flake shape is preferred.

  And although the average particle diameter of the aluminum pigment used for this invention is not specifically limited, It is preferable that it is 1 micrometer or more, and if it is especially 5 micrometers or more, it is more preferable. The average particle diameter is preferably 100 μm or less, more preferably 50 μm or less.

  When the average particle size is 1 μm or more, the handling in the manufacturing process is easy, and the aluminum pigment tends to hardly aggregate. When the average particle size is 100 μm or less, the surface of the coating film is used when used as a paint. Roughening can be prevented and a preferable design can be realized.

  Furthermore, the average thickness of the aluminum pigment used in the present invention is not particularly limited, but is preferably 0.02 μm or more, and more preferably 0.1 μm or more. The average thickness is preferably 5 μm or less, more preferably 2 μm or less. When this average thickness is 0.02 μm or more, it is advantageous in terms of ease of production process, and when the average thickness is 5 μm or less, it is advantageous in terms of the appearance of a coating composition such as a coating film.

  Here, the average particle size of the aluminum pigment used in the present invention is obtained by calculating the volume average based on the particle size distribution measured by a known particle size distribution measurement method such as a laser diffraction method. The average thickness is calculated from the hiding power and density of the aluminum pigment.

  Further, a grinding aid may be attached to the surface of the aluminum pigment used in the present invention. As such a grinding aid, conventionally known ones can be used without any particular limitation.

  Further, the method for obtaining the aluminum pigment used in the present invention is not particularly limited. For example, in the presence of a grinding medium in a ball mill or an attritor mill, the raw aluminum powder is ground using a grinding aid such as a fatty acid. Alternatively, it may be produced by grinding or may be obtained by crushing an aluminum-deposited foil in which aluminum is deposited on a film. As said grinding | pulverization medium, mineral oil of high flash point, such as a mineral spirit and solvent naphtha, can be used.

In addition, the above description is the same also about metal pigments other than an aluminum pigment.
<First coating layer>
The first coating layer of the present invention is formed on the surface of the metal pigment and has a function of imparting water resistance by densely coating the metal pigment. Such a 1st coating layer is comprised with a radically polymerizable resin or a 1st compound. In addition, water resistance here means the effect | action which suppresses generation | occurrence | production of gas, when a colored metal pigment is mix | blended with water | moisture content, such as mix | blending in water-based paint or water-based ink.

  The first coating layer preferably covers the entire surface of the metal pigment, but even if a part of the surface of the metal pigment is not covered by the first coating layer due to manufacturing conditions, etc. As long as the effect of the invention is shown, it does not depart from the scope of the present invention.

<Radically polymerizable resin>
Since the radical polymerizable resin can form an extremely dense film as compared with the thermal polymerization resin as described in Patent Document 3, the water resistance can be drastically improved.

  Here, the radical polymerizable resin refers to a resin that is polymerized by radical polymerization of monomers and / or oligomers having at least one polymerizable double bond. Therefore, such a radical polymerizable resin can be obtained by radical polymerization of a monomer and / or oligomer having at least one polymerizable double bond in this way, and therefore, on or around the above-mentioned metal pigment. By performing such radical polymerization, the first coating layer made of a radical polymerizable resin can be formed on the surface of the metal pigment. By forming such a radical polymerizable resin, a stable and dense coating layer is formed on the surface of the metal pigment, so that the water resistance of the finally obtained colored metal pigment is dramatically improved.

  When forming a 1st coating layer with such radically polymerizable resin, the quantity of radically polymerizable resin is 0.5-100 mass parts with respect to 100 mass parts of metal pigments, More preferably, 5-30 mass parts is preferable. Is appropriate. The amount of the radical polymerizable resin can be appropriately determined in consideration of the target thickness of the first coating layer, the specific surface area of the metal pigment, the density of the radical polymerizable resin to be coated, and the like.

  The thickness of the first coating layer composed of such a radical polymerizable resin is not particularly limited, but if it is 5 nm or more and 200 nm or less, the water resistance of the colored metal pigment (5 nm or less is insufficient), the coating film, etc. This is advantageous in terms of the appearance of the coating composition (the appearance is impaired at 200 nm or more). The thickness can be measured by observing the cross section of the colored metal pigment with a scanning electron microscope or the like.

  A specific method for coating a metal pigment with a radically polymerizable resin is to peroxidize a monomer and / or oligomer with a dispersion in which the metal pigment is dispersed in a hydrocarbon or alcohol solvent (preferably a hydrocarbon solvent). A method in which a polymerization initiator such as benzoyl, isobutyl peroxide, azobisisobutyronitrile, etc. is added and heated while stirring to radically polymerize the monomer and / or oligomer and deposit on the surface of the metal pigment is preferred.

  In this case, the addition amount of the polymerization initiator is preferably 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the monomer and / or oligomer. The polymerization reaction is desirably performed in an oxygen-free atmosphere, for example, an inert gas such as nitrogen or argon. The reaction temperature is suitably 50 to 150 ° C, more preferably 70 to 100 ° C. The reaction time is preferably 30 minutes or longer and 30 hours or shorter.

Examples of the monomer and / or oligomer include the following.
That is, acrylic acid, methacrylic acid, methyl methacrylate, butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, stearyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxybutyl acrylate, acrylic acid 2-methoxyethyl, 2-diethylaminoethyl acrylate, butyl methacrylate, octyl methacrylate, 1,4 butanediol diacrylate, 1,6 hexanediol diacrylate, 1,9 nonanediol diacrylate, neopentyl glycol diacrylate, Tripropylene glycol diacrylate, tetraethylene glycol diacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythris Tall triacrylate, trisacryloxyethyl phosphate, ditrimethylolpropane tetraacrylate, styrene, α-methylstyrene, vinyl toluene, divinylbenzene, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl propionate, maleic acid, crotonic acid, itaconic acid , Polybutadiene, linseed oil, soybean oil, epoxidized soybean oil, epoxidized polybutadiene, cyclohexene vinyl monooxide, divinylbenzene monooxide, mono (2-acryloyloxyethyl) acid phosphate, mono (2-methacryloyloxyethyl) acid phosphate, 2-acryloyloxyethyl acid phosphate, 2-methacryloyloxyethyl acid phosphate, (2-hydroxyethyl) Methacrylate acid phosphate, 2-methacryloyloxyethyl acid phosphate, 2-acryloyloxyethyl acid phosphate, diphenyl-2-methacryloyloxyethyl acid phosphate, diphenyl-2-acryloyloxyethyl acid phosphate Fate, Dibutyl-2-methacryloyloxyethyl acid phosphate, Dibutyl-2-acryloyloxyethyl acid phosphate, Dioctyl-2-methacryloyloxyethyl acid phosphate, Dioctyl-2-acryloyloxyethyl acid Dophosphate, 2-methacryloyloxypropyl acid phosphate, bis (2-chloroethyl) vinylphosphonate, di-2-methacryloyloxyethyl acid phosphate, Li-2-methacryloyloxyethyl acid phosphate, di-2-acryloyloxyethyl acid phosphate, tri-2-acryloyloxyethyl acid phosphate, diallyl dibutylphosphonosuccinate, acrylic modified polyester ( Polymerization degree 2-20), acrylic-modified polyether (polymerization degree 2-20), acrylic-modified urethane (polymerization degree 2-20), acrylic-modified epoxy (polymerization degree 2-20), acrylic-modified spirane (polymerization) However, it is not limited to these.

  Among them, when a monomer and / or oligomer having two or more polymerizable double bonds is used as the monomer and / or oligomer, a first coating layer formed of a three-dimensionally cross-linked radical polymerizable resin is formed, This is advantageous in that the water resistance is further improved.

  In addition, in the colored metal pigment, the identification of whether or not the first coating layer is composed of a radical polymerizable resin is performed by mass spectrometry, analysis of a polymerization initiator residue by NMR or the like, more simply molecular weight, It can be confirmed by molecular weight distribution, glass transition point, solubility in organic solvents, and the like.

<First compound>
The first compound constituting the first coating layer is an oxide or hydroxide of at least one element selected from the group consisting of Al, Si, Ti, Cr, Zr, Mo, and Ce. By using such a first compound, a stable and dense film against water is formed on the surface of the metal pigment, so that the water resistance of the finally obtained colored metal pigment is dramatically improved. In addition, it is preferable that such a 1st compound is colorless also in order not to inhibit the color development of the color pigment attached later.

  Specific examples of such a first compound include, for example, silicon oxide, polysiloxane condensate, aluminum oxide, titanium oxide, aluminum hydroxide, molybdenum oxide, chromium oxide, zirconium oxide, zirconium hydroxide, cerium oxide, water Examples thereof include cerium oxide. Among these, a condensate of silicon oxide and / or polysiloxane (that is, only silicon oxide, only a condensate of polysiloxane, or a mixture of both) is particularly preferable in terms of transparency, safety, and production cost.

  Such a 1st compound can comprise a 1st coating layer only by 1 type or in mixture of 2 or more types. The silicon oxide and polysiloxane condensate are both Si oxides, and the polysiloxane condensate means a compound in which an organosilicon compound is condensed by a siloxane bond.

  The usage-amount of such a 1st compound is 0.5 to 100 mass parts with respect to 100 mass parts of metal pigments, More preferably, 5 to 30 mass parts is preferable. The amount used can be determined in consideration of the thickness of the target first coating layer, the specific surface area of the metal pigment, the density of the first compound to be coated, and the like. The thickness of the first coating layer composed of the first compound is not particularly limited, but if it is 5 nm or more and 200 nm or less, the water resistance of the colored metal pigment (5 nm or less is insufficient) and the coating such as a coating film This is advantageous in terms of the appearance of the composition (the appearance is impaired at 200 nm or more). The thickness can be measured by observing the cross section of the colored metal pigment with a scanning electron microscope or the like.

  The method of coating the metal pigment with the first compound is not particularly limited, but a dispersion of the metal pigment in water and / or a hydrophilic solvent is mixed with Al, Si, Ti, Cr, Zr, Mo, and Ce. The first compound is deposited on the surface of the metal pigment by adding a precursor of the first compound such as any salt or alkoxide, and further adding a neutralizing agent for neutralizing the precursor or a hydrolysis catalyst for hydrolysis. Can be mentioned.

Examples of the hydrophilic solvent include the following:
Methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, t-butyl alcohol, n-butyl alcohol, isobutyl alcohol, ethyl cellosolve, butyl cellosolve, butyl carbitol, propylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl Ether, propylene glycol monopropyl ether, acetone.

Examples of the precursor of the first compound include the following:
Aluminum nitrate, cerium nitrate, cerium acetate, titanyl sulfate, ammonium molybdate salts, methyltriethoxysilane, methyltrimethoxysilane, tetraethoxysilane, tetramethoxysilane, tetraisopropoxysilane, tetraisopropoxytitanium, tetrabutoxytitanium , Tetrabutoxyzirconium, triisopropoxyaluminum and the like and their condensates.

Examples of the neutralizing agent and hydrolysis catalyst include the following:
Neutralizing agent: ammonia, sodium hydroxide, potassium hydroxide and the like.
Basic hydrolysis catalyst: monoethanolamine, diethanolamine, triethanolamine, ammonia, ethylenediamine, t-butylamine, γ-aminopropyltriethoxysilane, N-2-aminoethyl-3-aminopropyltriethoxysilane, N-2 -Aminoethyl-3-aminopropylmethyldimethoxysilane, urea, sodium silicate, sodium hydroxide and the like.
Acid hydrolysis catalyst: oxalic acid, acetic acid, nitric acid, sulfuric acid, phosphoric acid, phosphonic acid, etc.

  As described above, a condensate of silicon oxide and / or polysiloxane is particularly preferable as the first compound, and the method for forming the first coating layer using these compounds includes, for example, a metal pigment and a silicon compound in the case of silicon oxide. A method of stirring or kneading the solution in a slurry state or a paste state while keeping the solution basic or acidic can be employed, whereby a first coating layer made of silicon oxide can be formed on the surface of the metal pigment. In the case of a polysiloxane condensate, for example, the first coating layer made of the polysiloxane condensate is formed on the surface of the metal pigment by hydrolyzing and condensing the alkoxysilane in the presence of the metal pigment and alkoxysilane. Can be formed. However, it is not limited only to these methods.

<Coloring pigment>
The colored pigment of the present invention adheres to the surface of the first coating layer. However, when the organic phosphate compound layer is formed on the first coating layer as described later, it adheres to the surface of the organic phosphate compound layer. You may do it. Therefore, the expression “color pigment attached to the surface of the first coating layer” in the present invention is not limited to the case where the color pigment is directly attached to the surface of the first coating layer, unless otherwise specified. Including the case where it adheres to the surface.

  In the present invention, the above-mentioned metal pigment mainly has a function of imparting a metallic luster, and since it is often achromatic in color, this colored pigment mainly has a function of imparting a chromatic color. However, the present invention is not limited to this. For example, it may have an action of imparting an achromatic color such as white or black.

  Such coloring pigments can be used without any particular limitation on conventionally known pigments. For example, the following can be illustrated.

  That is, organic pigments such as diketopyrrolopyrrole, quinacridone, dioxazine, isoindolinone, condensed azo, selenium, perinone, perylene, quinophthalone, and phthalocyanine, inorganic such as iron oxide and carbon black A pigment etc. can be mentioned.

  Specifically, phthalocyanine, halogenated phthalocyanine, quinacridone, diketopyrrolopyrrole, isoindolinone, azomethine metal complex, indanthrone, perylene, perinone, anthraquinone, dioxazine, benzimidazolone, condensed azo, triphenylmethane, quinophthalone, Examples include anthrapyrimidine, iron oxide, ultramarine blue, bitumen, cobalt blue, chromium green, bismuth vanadate, composite oxide calcined pigment, carbon black, titanium black, titanium oxide, and ultrafine titanium oxide.

  Particularly preferred pigments in terms of adhesion to metal pigments, weather resistance and coloring power are phthalocyanine blue, phthalocyanine green, quinacridone red, quinacridone maroon, quinacridone gold, diketopyrrolopyrrole, isoindolinone yellow, isoindolinone orange. , Anthrapyrimidine yellow, dioxazine violet, perylene maroon, azomethine copper complex, transparent iron oxide, carbon black, ultrafine titanium oxide and the like.

  The primary particle diameter of such a colored pigment is not particularly limited, but a pigment having a primary particle diameter of preferably 0.01 to 1 μm, more preferably 0.02 to 0.1 μm can be used. When the primary particle size is 0.01 μm or more, there is less risk of dispersion of the pigment, and when the primary particle size is 1.0 μm or less, it is difficult to uniformly adhere to the surface of the metal pigment. There is little nature.

  The adhesion amount of the color pigment is 1 part by mass or more and 200 parts by mass or less, more preferably 10 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the metal pigment. The adhesion amount is preferably adjusted as appropriate according to the specific surface area of the metal pigment. When the adhesion amount is less than 1 part by mass, sufficient saturation cannot be obtained with respect to the finally obtained colored metal pigment, and when the adhesion amount exceeds 200 parts by mass, the brightness of the finally obtained color metal pigment is obtained. The feeling decreases.

  In addition, it is more preferable that the surface of the color pigment is treated with the following compound in order to improve adhesion.

  That is, examples of such compounds include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1,7-diaminoheptane, 1,8-diaminooctane, 1,10-diaminodecane, , 12-diaminododecane, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 1,8-diaminonaphthalene, 1,2-diaminocyclohexane, stearylpropylenediamine, N-β- (aminoethyl) -γ- Aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-2-aminoethyl-3-aminopropylmethyldimethoxysilane, benzoic acid, vinyl benzoate, salicylic acid, anthrani Acid, m-aminobenzoic acid, o-aminobenzoic acid, p-aminobenzoic acid, 3-amino-4-methylbenzoic acid, p-aminosalicylic acid, 1-naphthoic acid, 2-naphthoic acid, naphthenic acid, 3- Examples thereof include amino-2-naphthoic acid, cinnamic acid, aminocinnamic acid, and the like, but are not limited thereto.

<Organic phosphate compound layer>
In the colored metal pigment of the present invention, an organic phosphate compound layer can be formed on the first coating layer. In this case, the above-mentioned colored pigment adheres to the surface of the organic phosphoric acid compound layer, and constitutes a preferred embodiment of the present invention. That is, such an organic phosphoric acid compound layer has a function of improving the adhesion of the color pigment.

  Such an organic phosphate compound layer is assumed to be formed by chemically or physically adsorbing the organic phosphate compound on the surface of the first coating layer. Moreover, the organic phosphoric acid compound layer may be formed in a layered state on the surface of the first coating layer, or may be formed in a state of being scattered on the surface instead of the layered state. That is, the organic phosphoric acid compound layer in the present invention is not limited to the case where the organic phosphoric acid compound is present in a continuous layer state on the first coating layer, but the organic phosphoric acid compound does not constitute a layer and is scattered on the first coating layer. It also includes the case where it exists. In short, the organic phosphoric acid compound layer in the present invention only needs to be present in an amount corresponding to the amount of the color pigment to be attached later, and the presence state is not limited.

  By forming such an organic phosphoric acid compound layer on the surface of the first coating layer, the adherence of the color pigment to be adhered later becomes good, and a colored metal pigment with high chroma is obtained. Furthermore, it is possible to suppress the dropout of the color pigment when the color metal pigment is dispersed in a solvent or paint.

  The organic phosphoric acid compound constituting such an organic phosphoric acid compound layer means a compound having a structure in which part of the OH group of phosphoric acid is substituted with an organic substituent. Such an organic phosphate compound is not particularly limited, and examples thereof include organic phosphate esters. Examples of the organic phosphate ester include stearyl acid phosphate, myristyl acid phosphate, palmityl acid phosphate, lauryl acid phosphate, polyoxyethylene alkylphenyl ether acid phosphate, n-decyl acid phosphate, 2-ethylhexyl acid phosphate, oleyl acid phosphate, Examples include hexyl acid phosphate, butyl acid phosphate, and ethylene glycol acid phosphate.

  Such an organic phosphate compound layer is preferably composed of an organic phosphate compound having at least one polymerizable double bond. Examples of such a compound include at least one polymerizable double bond. And organic phosphoric acid esters having Examples of the organic phosphate ester having at least one polymerizable double bond include oleyl acid phosphate, mono (2-acryloyloxyethyl) acid phosphate, mono (2-methacryloyloxyethyl) acid phosphate, and 2-acryloyloxy. Ethyl acid phosphate, 2-methacryloyloxyethyl acid phosphate, (2-hydroxyethyl) methacrylate acid phosphate, 2-methacryloyloxyethyl acid phosphate, 2-acryloyloxyethyl acid phosphate, diphenyl-2-methacryloyl Roxyethyl acid phosphate, diphenyl-2-acryloyloxyethyl acid phosphate, dibutyl-2-methacryloyloxyethyl acid phosphate Dibutyl-2-acryloyloxyethyl acid phosphate, dioctyl-2-methacryloyloxyethyl acid phosphate, dioctyl-2-acryloyloxyethyl acid phosphate, 2-methacryloyloxypropyl acid phosphate Organophosphoric acid compounds having one polymerizable double bond such as fete, bis (2-chloroethyl) vinylphosphonate, di-2-methacryloyloxyethyl acid phosphate, tri-2-methacryloyloxyethyl acid phosphate Organic phosphate compounds having two or more polymerizable double bonds such as di-2-acryloyloxyethyl acid phosphate, tri-2-acryloyloxyethyl acid phosphate, diallyl dibutylphosphonosuccinate, etc. Can mention .

  In the present invention, it is preferable to use a compound having at least one polymerizable double bond as the organic phosphate compound constituting such an organic phosphate compound layer, and a compound having two or more polymerizable double bonds is used. It is more preferable. This is because the adhesion of the color pigment is particularly good.

  Although the usage-amount of an organic phosphoric acid compound is not specifically limited, 0.1 mass part or more and 10 mass parts with respect to 100 mass parts of metal pigments in which the 1st coating layer was formed, More preferably, 0.5 mass part or more and 5 mass parts Or less. If it is 0.1 part by mass or more, it is advantageous in terms of adhesion of the colored pigment, and if it is 10 parts by mass or less, the film performance of a coating film using a colored metal pigment (such as adhesion, This is advantageous in that the weather resistance and the like are reduced).

  In the colored metal pigment of the present invention, the presence of such an organic phosphate compound layer can be specified by detection and quantification of P (phosphorus) by ICP (Inductively Coupled Plasma) analysis or the like.

<Second coating layer>
In the colored metal pigment of the present invention, it is preferable that a second coating layer is further formed on the coloring pigment attached to the surface of the first coating layer. By forming the second coating layer, the colored pigment adheres more firmly and the water resistance is further improved.

  Although the composition of the second coating layer is not particularly limited, it can be composed of a radical polymerizable resin or a first compound, for example, similarly to the first coating layer. In particular, such a second coating layer is preferably composed of a radical polymerizable resin. This is because the second coating layer becomes a denser layer having excellent solvent resistance, so that the color pigments are less likely to drop off or deteriorate.

  Moreover, the formation method of such a 2nd coating layer is not specifically limited, The method similar to a 1st coating layer is employable. The thickness of the second coating layer is not particularly limited, but if it is 5 nm or more and 200 nm or less, the water resistance of the colored metal pigment (5 nm or less is insufficient) and the appearance of the coating composition such as a coating film (200 nm or more) Is advantageous in that the appearance is impaired. The thickness can be measured by observing the cross section of the colored metal pigment with a scanning electron microscope or the like.

<Method for producing colored metal pigment>
The method for producing a colored metal pigment of the present invention comprises a first step of preparing a coated metal pigment having a first coating layer formed on the surface of the metal pigment, and a colored pigment on the surface of the first coating layer of the coated metal pigment. And a second step of depositing.

  Here, as described above, the first coating layer is composed of the radical polymerizable resin or the first compound, and the first compound is also as described above. Hereinafter, each step will be described in more detail.

<First step>
The first step of the present invention is a step of preparing a coated metal pigment having a first coating layer formed on the surface of the metal pigment. The preparation of the coated metal pigment having the first coating layer formed on the surface of the metal pigment can be prepared by purchasing a commercially available coated metal pigment having such a configuration, or the first coating layer is formed. It can also be prepared by preparing an untreated metal pigment and forming the first coating layer on the surface of this metal pigment by the method described for the first coating layer.

<Second step>
The second step of the present invention is a step of attaching a colored pigment to the surface of the first coating layer of the coated metal pigment. The method for attaching the color pigment to the surface of the first coating layer of the coated metal pigment is not particularly limited, and examples thereof include the following method.

  That is, as a first step, a colored pigment is dispersed in a solvent, preferably a nonpolar solvent, to prepare a colored pigment dispersion (slurry). At this time, as described above, the specific compound may be added to the dispersion for the purpose of treating the surface of the color pigment with a specific compound such as ethylenediamine in order to improve the adhesion of the color pigment. . Moreover, you may add dispersing agents, such as surfactant and a chelate compound, in this dispersion as needed.

  Here, as the nonpolar solvent, aliphatic hydrocarbons, aromatic hydrocarbons having a boiling range of about 100 ° C. to 250 ° C., mixed solvents thereof, and the like can be suitably used. Specific examples include normal paraffin, isoparaffin, toluene, xylene, solvent naphtha, kerosene, mineral spirit, and petroleum benzine, but are not limited thereto. If necessary, an alcohol or ester solvent may be added in a small amount as an aid for dispersion of the color pigment.

  The method for dispersing the color pigment is not particularly limited, and examples thereof include a dispersion method using a grinding medium such as a ball mill, a bead mill, and a sand mill. Although the dispersion time is not particularly limited, it is within the range of 30 minutes to 30 hours that the colored metal pigment has good designability (decrease in designability below 30 minutes) and productivity (productivity below 30 hours is poor) Is more preferable. Moreover, the temperature at the time of dispersion | distribution is not specifically limited, What is necessary is just in the range of 0 to 100 degreeC.

  Next, as a second stage, the metal pigment with the first coating layer (that is, the coating metal pigment) is added to the dispersion of the color pigment prepared above and dispersed further, and the color pigment adheres to the surface of the first coating layer. Let As a dispersion method in this case, stirring with a stirrer or a disper is also suitable in addition to the above-described dispersion method.

  The dispersion time in the second stage is not particularly limited, but is within the range of 30 minutes to 30 hours. The dispersion degree of the color pigment (the pigment cannot be sufficiently dispersed in 30 minutes or less) and the productivity (productivity in 30 hours or more). This is preferable for the reason of (decrease). Moreover, the temperature at the time of dispersion | distribution is not specifically limited, What is necessary is just in the range of 0 to 100 degreeC.

  By passing through such a 2nd process, the colored metal pigment of this invention which the colored pigment adhered to the surface of the 1st coating layer of a coated metal pigment can be obtained. As is clear from the above description, the adhesion of the color pigment to the surface of the first coating layer is considered to be physical adsorption or chemical adsorption.

  In the above description, the first stage and the second stage have been described separately. However, there is no reason why the first stage and the second stage should be performed in this order. Also, a method of adding and dispersing all the components used in the second stage at a time can be adopted as long as the effect of the present invention is not impaired.

<Additional process>
The method for producing a colored metal pigment of the present invention includes an additional step of forming an organic phosphate compound layer by adsorbing an organic phosphate compound on the surface of the first coating layer of the coated metal pigment after the first step. In this case, the second step is a step of attaching a color pigment onto the organic phosphoric acid compound layer formed in the addition step. By performing such an additional step, the adhesion of the colored pigment performed in the second step is improved.

  The method for adsorbing the organic phosphoric acid compound on the surface of the first coating layer of the coated metal pigment is not particularly limited, and can be carried out, for example, by the following method.

  That is, the coated metal pigment is brought into contact with a solution obtained by dissolving the organophosphate compound in a solvent exemplified below and dispersed at a predetermined temperature for a predetermined time, whereby the organic phosphate compound is formed on the surface of the first coating layer of the coated metal pigment. Can be adsorbed.

  Examples of the solvent include methanol, ethanol, 1-propanol, isopropyl alcohol, n-butanol, s-butanol, t-butanol, glycerin, allyl alcohol, ethylene glycol, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, and ethylene glycol. Examples include monomethoxymethyl ether, diethylene glycol, propylene glycol monobutyl ether, acetone, acetylacetone, methyl ethyl ketone, diethyl ketone, cyclohexanone, diacetone alcohol, methyl isobutyl ketone, methyl-n-butyl ketone, methyl-n-propyl ketone, dimethyl sulfoxide and the like. .

  Moreover, as a method to contact, the method of processing in a slurry state, the method of kneading in a paste state, etc. can be employ | adopted, However, It is not limited only to these. Further, the treatment temperature is not limited, but it is preferably performed at 5 ° C. or higher and 100 ° C. or lower, preferably 30 ° C. or higher and 70 ° C. or lower. Also, the treatment time is not particularly limited, but it is preferably 1 minute to 180 minutes, preferably 10 minutes to 60 minutes.

  In addition, when performing such an additional process, a 2nd process can be performed by the method similar to the method already demonstrated above. That is, it is possible to employ a method such as adding a coated metal pigment having an organic phosphoric acid compound layer formed on the surface thereof to a colored pigment dispersion to disperse it.

<Third step>
The method for producing a colored metal pigment of the present invention can further include a third step of forming a second coating layer on the colored pigment after the second step. Thereby, the adhesion of the colored pigment becomes stronger and the water resistance is further improved.

  Although such a 3rd process is not specifically limited, A 2nd coating layer can be formed by the method similar to the method of forming a 1st coating layer.

<Coating composition>
The present invention also relates to a coating composition comprising the colored metal pigment described above. Such a coating composition usually contains a colored metal pigment, a resin component, and a solvent. In particular, an aqueous coating composition using a hydrophilic solvent as a solvent is excellent in water resistance, stable and excellent in color development.

  The compounding amount of the colored metal pigment in the coating composition of the present invention is 0.1 to 50 parts by mass, more preferably 1 to 30 parts by mass with respect to 100 parts by mass of the resin component. preferable. When the amount of the colored metal pigment is less than 0.1 parts by mass, the intended designability cannot be obtained, and when it is more than 50 parts by mass, the sharpness of the coating film decreases.

  The blending amount of the solvent in the coating composition of the present invention is preferably 1 part by mass or more and 100 parts by mass or less, more preferably 5 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the resin component. When the amount of the solvent is less than 1 part by mass, the dispersibility of the colored metal pigment in the coating composition becomes insufficient. When the amount is more than 100 parts by mass, environmental pollution due to the solvent that evaporates when the coating is dried and cured becomes a problem.

  The resin component blended in the coating composition of the present invention is not particularly limited. For example, thermosetting acrylic resin / melamine resin, thermosetting acrylic resin / CAB (cellulose acetate butyrate) / melamine resin, thermosetting type. Examples include polyester (alkyd) resin / melamine resin, thermosetting polyester (alkyd) / CAB / melamine resin, isocyanate curable urethane resin / room temperature curable acrylic resin, water-diluted acrylic emulsion / melamine resin, and the like.

  Although the solvent mix | blended with the coating composition of this invention is not specifically limited, Hydrophilic solvent (For example, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl), such as water, alcohol type, glycol type, ketone type, ester type, etc. Alcohol, t-butyl alcohol, n-butyl alcohol, isobutyl alcohol, ethyl cellosolve, butyl cellosolve, butyl carbitol, propylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monopropyl ether, acetone, ethyl acetate , Propyl acetate, etc.), aromatic solvents, alicyclic solvents, hydrocarbon solvents such as benzene, toluene, xylene, hexane, heptane, cyclohexane, Octane, it is possible to use mineral spirits, etc.).

  Moreover, additives such as pigment dispersants, antifoaming agents, anti-settling agents, curing catalysts, and other colored pigments can be blended with such coating compositions as necessary.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these. Examples 4, 5 and 8 are reference examples.

<Example 1>
<First step>
First, an aluminum pigment was used as the metal pigment. This aluminum pigment has a paste-like form by washing the paste containing it (trade name: “5620NS”, manufactured by Toyo Aluminum Co., Ltd., average particle size 18 μm) with mineral spirits and then filtering. there were. The non-volatile component (aluminum pigment) of the paste after filtration was 70% by mass (the balance was mineral spirit).

  After adding 214 g (150 g as a solid content) of this paste and 2000 g of mineral spirit to a 3 liter separable flask, the mixture was stirred to obtain a slurry. While continuing the stirring, nitrogen gas was introduced into the system to create a nitrogen atmosphere. Then, it heated up to 80 degreeC.

  Next, 0.75 g of acrylic acid, 6.75 g of trimethylolpropane trimethacrylate, 7.50 g of epoxidized polybutadiene (diluted to 50% by mass with mineral spirits), 3.75 g of styrene as monomers constituting the first coating layer And 0.75 g of azobisisobutyronitrile (AIBN) as a polymerization initiator is added to the above slurry, and these monomers are radically polymerized to form a first coating layer comprising a radically polymerizable resin on the surface of the aluminum pigment. Formed.

  Subsequently, the reaction was terminated by cooling 8 hours after the AIBN was added. Subsequently, the above slurry was filtered and washed with a small amount of mineral spirits to prepare a coated metal pigment in which a first coating layer made of a radical polymerizable resin was formed on the surface of the metal pigment.

<Additional process>
The coated metal pigment prepared in the first step was washed with propylene glycol monomethyl ether. Then, 150 g (in terms of solid content) of the washed coated metal pigment was added to 1.5 g of di-2-methacryloyloxyethyl acid phosphate (1% by mass based on the coated metal pigment), which is an organic phosphate compound, in propylene glycol. The solution was added to a solution dissolved in 400 g of monobutyl ether and stirred at 75 ° C. for 1 hour to obtain a slurry. The obtained slurry was subjected to solid-liquid separation, and a colored metal pigment precursor paste (solid content: 70% by mass) having an organic phosphate compound layer formed by adsorbing the organic phosphate compound on the surface of the first coating layer was obtained.

<Second step>
Commercially available phthalocyanine blue pigment (trade name: “Lionol Blue PM7185” (primary average particle size 0.02 μm), Toyo Ink Co., Ltd. 20 g, N-2-aminoethyl-3-aminopropylmethyldimethoxysilane (2.5% by mass with respect to the colored pigment) and 30 g of mineral spirit are added, and the colored pigment is dispersed by a ball mill for 24 hours. did.

  Thereafter, 42.9 g of the colored metal pigment precursor paste (30 g as the solid content) and 30 g of mineral spirit that were subjected to the above addition step and 30 g of mineral spirit were added to the pot mill and further dispersed by a ball mill for 1 hour. By this step, the colored pigment adhered to the surface of the organic phosphoric acid compound layer of the colored metal pigment precursor.

  By washing the slurry thus obtained with 500 g of mineral spirits, the glass beads and the target product are separated and then filtered to form a surface of the organophosphate compound layer formed on the first coating layer. A colored metal pigment (colored aluminum pigment) of the present invention having a colored pigment adhered thereto was obtained.

<Third step>
In a slurry in which 20 g (as a solid content) of the colored metal pigment obtained above was dispersed in 200 g of mineral spirit, 0.3 g of acrylic acid, 0.3 g of trimethylolpropane triacrylate, 0.3 g of styrene, 0. 3g was added and 0.05 g of azobisisobutylnitrile was added as a polymerization initiator while heating and stirring at 80 ° C. in nitrogen to radically polymerize these monomers. A second coating layer composed of a radically polymerizable resin was formed on the colored pigment of the pigment.

  After this treatment, the slurry was subjected to solid-liquid separation to obtain the colored metal pigment of the present invention in which the second coating layer was formed on the colored pigment in a paste state (solid content 60 mass%).

<Example 2>
<First step>
In the same manner as in Example 1, 200 g (in terms of solid content) of a coated metal pigment was prepared.

<Additional process>
The coated metal pigment prepared in the first step was washed with propylene glycol monomethyl ether. Then, 150 g (in terms of solid content) of the washed coated metal pigment was added to 1.5 g (1% by mass with respect to the coated metal pigment) of mono (2-methacryloyloxyethyl) acid phosphate, which is an organic phosphate compound, in propylene glycol monobutyl ether. The solution dissolved in 400 g was charged and stirred at 75 ° C. for 1 hour to obtain a slurry. The obtained slurry was subjected to solid-liquid separation, and a colored metal pigment precursor paste (solid content: 70% by mass) having an organic phosphate compound layer formed by adsorbing the organic phosphate compound on the surface of the first coating layer was obtained.

<Second step>
Commercially available diketopyrrolopyrrole pigment (trade name: “Irgazine DPP Rubin TR” (particle size: 0.02 μm), manufactured by BASF) in a pot mill having a diameter of 5 cm and an internal volume of 500 cc with 500 g of glass beads having a diameter of 1 mm inserted. 20 g, 0.5 g of o-aminobenzoic acid (2.5% by mass with respect to the colored pigment) and 30 g of mineral spirit were added, and the colored pigment was dispersed by a ball mill for 24 hours.

  Thereafter, 42.9 g of the colored metal pigment precursor paste (30 g as the solid content) and 30 g of mineral spirit that were subjected to the above addition step and 30 g of mineral spirit were added to the pot mill and further dispersed by a ball mill for 1 hour. By this step, the colored pigment adhered to the surface of the organic phosphoric acid compound layer of the colored metal pigment precursor.

  By washing the slurry thus obtained with 500 g of mineral spirits, the glass beads and the target product are separated and then filtered to form a surface of the organophosphate compound layer formed on the first coating layer. A colored metal pigment (colored aluminum pigment) of the present invention having a colored pigment adhered thereto was obtained.

<Example 3>
The coloring of the present invention is the same as in Example 1 except that the coated metal pigment prepared in the first step is used instead of the coated metal pigment prepared as follows. A metal pigment (a paste state having a solid content of 60% by mass) was obtained.

  That is, 0.5 g of metal molybdenum powder was added little by little to 10 g of hydrogen peroxide containing 30% by mass of hydrogen peroxide, and the resulting solution was dissolved in 600 g of isopropyl alcohol (hereinafter referred to as “IPA”).

  Subsequently, 143 g (100 g as a solid content) of an aluminum pigment (trade name: “5620NS”, manufactured by Toyo Aluminum Co., Ltd.) as a metal pigment was added to this IPA solution, and the mixture was stirred and mixed at 50 ° C. for 1 hour. Thus, a slurry was obtained. This formed the 1st coating layer which consists of molybdenum oxides on the surface of the aluminum pigment as a metal pigment.

Next, ammonia water and 20 g of water were added to the slurry to adjust the pH value of the slurry to 8.5. And what melt | dissolved 40 g of tetraethoxysilane in 100-g IPA was dripped gradually with respect to this slurry after pH adjustment, and also it stirred and mixed at 75 degreeC for 2 hours. Thereafter, the slurry was subjected to solid-liquid separation with a filter to prepare and use a coated metal pigment in which a first coating layer made of silicon oxide (first compound) was further formed on the first coating layer. This coated metal pigment has a structure in which a first coating layer having a two-layer structure is formed.

<Example 4>
The colored metal pigment of the present invention (a paste with a solid content of 60% by mass) was obtained in the same manner as in Example 1 except that the addition step was not performed on Example 1. That is, such a colored metal pigment has a structure in which the colored pigment is attached to the surface of the first coating layer formed on the surface of the metal pigment, and the second coating layer is formed on the colored pigment.

<Example 5>
A colored metal pigment of the present invention (a paste with a solid content of 60% by mass) was obtained in the same manner as in Example 3 except that the addition step was not performed on Example 3. That is, such a colored metal pigment has a structure in which the colored pigment is attached to the surface of the first coating layer formed on the surface of the metal pigment, and the second coating layer is formed on the colored pigment.

<Example 6>
The present invention is the same as Example 1 except that oleyl acid phosphate was used instead of di-2-methacryloyloxyethyl acid phosphate used in the addition step for Example 1. A colored metal pigment (a paste state having a solid content of 60% by mass) was obtained.

<Example 7>
The coloring of the present invention is the same as in Example 2 except that the coated metal pigment prepared in the following manner is used instead of the coated metal pigment prepared in the first step. A metal pigment (a paste state having a solid content of 60% by mass) was obtained.

That is, to 500 g of propylene glycol monomethyl ether, 143 g (100 g as solid content) of an aluminum pigment (trade name: “5620NS”, manufactured by Toyo Aluminum Co., Ltd., manufactured by Toyo Aluminum Co., Ltd.) as a metal pigment was added, and the liquid temperature was 18 ° C. It was dispersed while keeping A solution prepared by dissolving 5 g of ammonium paramolybdate ((NH ₄ ) ₆ Mo ₇ O ₂₄ · 4H ₂ O) in 100 g of deionized water was gradually added to this dispersion, and the liquid temperature was 15 to 20 ° C. The mixture was stirred for 1 hour. Thereafter, the slurry was subjected to solid-liquid separation with a filter to prepare and use a coated metal pigment in which a first coating layer made of molybdenum oxide was formed on the surface of the metal pigment.

<Example 8>
The colored metal pigment (colored) of the present invention in which the colored pigment adheres on the first coating layer by performing the same steps as in Example 2 except that the additional step was not performed on Example 2. An aluminum pigment) was obtained.

<Comparative Example 1>
Compared to Example 1, a metal pigment in which the first coating layer is not formed instead of the first step (that is, an aluminum pigment (trade name: “5620NS” as a metal pigment, manufactured by Toyo Aluminum Co., Ltd.), an average particle diameter of 18 μm. )) Was prepared, and a colored metal pigment (a paste state having a solid content of 60% by mass) was obtained in the same manner as in Example 1 except that the addition step was not performed.

<Comparative Example 2>
In contrast to Example 2, instead of the coated metal pigment prepared in the first step, an aluminum pigment coated with an iron oxide layer on the surface (trade name: “Pariochrome Gold L2020” (particle size 20 μm), manufactured by BASF In the same manner as in Example 2, except that no additional step was performed, a colored metal pigment (a paste state having a solid content of 60% by mass) was obtained.

<Comparative Example 3>
For Example 2, instead of the coated metal pigment prepared in the first step, an aluminum pigment whose surface was treated with inorganic phosphoric acid prepared as described below was prepared, and no additional step was performed. Except for the above, a colored metal pigment (a paste with a solid content of 60% by mass) was obtained in the same manner as Example 2 except for the above.

  That is, 20 g of an isopropyl alcohol solution containing 1.0 g of phosphoric acid was added to 143 g (100 g as a solid content) of a commercially available aluminum pigment (trade name: “5620NS”, manufactured by Toyo Aluminum Co., Ltd., average particle size 18 μm) and kneaded for 5 minutes. Thus, an aluminum pigment having a phosphate group adsorbed on the surface was prepared and used.

<Comparative Example 4>
To 500 g of mineral spirit, 143 g of a commercially available aluminum pigment (trade name: “5620NS”, manufactured by Toyo Aluminum Co., Ltd., average particle size 18 μm), carboxylic acid having a double bond obtained by thermal polymerization of acrylic acid and soybean oil fatty acid ( Trade name: “Diacid 1550” (manufactured by Harima Kasei Kogyo Co., Ltd.) (3.6 g) was added, and the mixture was vigorously stirred in a nitrogen gas atmosphere at 90 ° C. for 1 hour.

  Next, the dispersion thus obtained was cooled to room temperature, and then solid-liquid separation was performed to obtain a heat-polymerized carboxylic acid-treated aluminum pigment having a nonvolatile content of 60%.

  And with respect to Example 1, this heat polymerization carboxylic acid treatment aluminum pigment was used, and the 2nd process after Example 1 was implemented with respect to this pigment, and the colored metal pigment was obtained. This colored metal pigment has a structure in which a coating layer made of a thermopolymerizable resin is formed instead of the first coating layer of the present invention.

  The following tests were conducted using the colored metal pigments of Examples 1 to 8 and Comparative Examples 1 to 4 obtained as described above.

<Test 1>
2.5 g of each colored metal pigment obtained in Examples 1 to 8 and Comparative Examples 1 to 4 was dispersed in 50 g of a commercially available acrylic lacquer (trade name: “Autoclear”, manufactured by Nippon Paint Co., Ltd.) to obtain a paint. A coated plate was prepared by applying and applying this paint on a double-sided art paper using a 250 μm doctor blade.

  And the saturation value of each coating plate produced in this way was measured using a multi-angle spectrocolorimeter (trade name: “X-Rite MA-68II”, manufactured by X-Rite). The saturation value (C *) was calculated by the following equation using a * value and b * value which are measured values at an incident angle of 45 ° and an offset angle of 15 °. The saturation value (C *) indicates that the higher the numerical value, the higher the saturation. The results are shown in Table 1.

Saturation value (C *) = (a * ² + b * ² ) ^1/2
<Test 2>
After adding 0.2 g and 20 g of ethyl acetate as solids to each colored metal pigment obtained in Examples 1-8 and Comparative Examples 1-4 in a 20 ml capacity test tube and shaking well to disperse, 3 hours It left still and observed the elution state of a coloring pigment. In this test, when the adhesion of the colored pigment is insufficient, the supernatant liquid is colored by the eluted color pigment, and when the adhesion is good, the supernatant liquid becomes transparent. The transparency of the supernatant liquid was visually evaluated and indicated in the following four stages. The closer the supernatant liquid is to colorless and transparent, the more stable color development (that is, the higher the adhesion of the colored pigment). The results are shown in Table 1.
A: It is colorless and transparent.
B: Transparent but slightly colored.
C: Transparent but colored.
D: Opaque and colored.

<Test 3>
Using the colored metal pigments obtained in Examples 1 to 8 and Comparative Examples 1 to 4, aqueous coating compositions were prepared as follows.

<Preparation of rheology control agent>
Rheology control by stirring and mixing 19.5 parts by mass of a polyamide-based rheology control agent (trade name: “Disparon AQ600”, manufactured by Enomoto Kasei Co., Ltd.), 6 parts by mass of butyl cellosolve, and 106.5 parts by mass of ion-exchanged water. An agent (Composition 1) was prepared.

<Preparation of resin solution>
27.9 parts by mass of acrylic copolymer (trade name: “Setaqua 6802”, manufactured by Neuplex), 16.8 parts by mass of polyurethane dispersion A (trade name: “Bayhydrol XP 2621”, manufactured by Bayer MaterialScience), polyurethane disperser John B (trade name: “Bayhydrol PT241”, Bayer MaterialScience) 4.1 parts by weight, melamine resin solution (trade name: “Cymel327”, Mitsui Cytec) 1.9 parts by weight, butyl cellosolve 5.3 Resin by mixing 0.3 parts by weight of defoaming leveling agent (trade name: “AQ7120”, manufactured by Enomoto Kasei Co., Ltd.) and 12.4 parts by weight of ion-exchanged water for 30 minutes or more. A solution (Composition 2) was prepared.

<Preparation of metallic base>
A dispersant (trade name: “AQ320”, manufactured by Enomoto Kasei Co., Ltd.) 0.4 mass to each colored metal pigment (4.4 mass parts as a solid content) obtained in Examples 1 to 8 and Comparative Examples 1 to 4 Parts and butyl cellosolve were added to make the whole 15.00 parts by mass, and the mixture was stirred and mixed for 10 minutes to prepare a metallic base (Composition 3).

<Preparation of aqueous coating composition>
To 96.2 parts by mass of the resin solution (Composition 2), 10.5 parts by mass of the metallic base (Composition 3) was added and mixed with stirring for 10 minutes or more. Next, 12.3 parts by mass of the rheology control agent (Composition 1) was gradually added to the mixture, and then the mixture was further stirred and mixed for 10 minutes. Then, a 10% dimethylethanolamine aqueous solution was added so that the pH of the mixture was 8.3 ± 0.1, and the mixture was further stirred and mixed for 10 minutes or more. Finally, an appropriate amount of ion-exchanged water was added so that the viscosity became a reference value (25 seconds for Ford cup No. 4), and the mixture was stirred and mixed for 10 minutes or more to obtain an aqueous coating composition.

  Then, 80 g of each aqueous coating composition prepared as described above was collected and the amount of accumulated hydrogen gas generated when stored in a water bath adjusted to 50 ° C. for 7 days was measured using a graduated cylinder by the water displacement method. did. The smaller the amount of gas generated, the better the water resistance. The results are shown in Table 1.

  As is clear from Table 1, it is clear that the colored metal pigment of the present example is superior in water resistance and stable color development and exhibits high chroma as compared with the colored metal pigment of the comparative example.

  Although the embodiments and examples of the present invention have been described as described above, it is also planned from the beginning to appropriately combine the configurations of the above-described embodiments and examples.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

Claims (9)

A metal pigment, a first coating layer formed on the surface of the metal pigment, an organic phosphate compound layer formed on the first coating layer, a surface of the first coating layer, or a surface of the organic phosphate compound layer And a coloring pigment attached to the
The first coating layer is composed of a radical polymerizable resin or a first compound,
The colored metal pigment, wherein the first compound is an oxide or hydroxide of at least one element selected from the group consisting of Al, Si, Ti, Cr, Zr, Mo, and Ce. The colored metal pigment according to claim 1 , wherein the organic phosphoric acid compound layer is composed of an organic phosphoric acid compound having at least one polymerizable double bond. Wherein on color pigments are further the second covering layer formed, colored metallic pigment according to claim 1 or 2. The colored metal pigment according to any one of claims 1 to 3 , wherein the metal pigment is an aluminum pigment. The radical-polymerizable resin is obtained by radical polymerization of a monomer and / or oligomer having at least one polymerizable double bond, color metallic pigment according to any one of claims 1-4. The colored metal pigment according to any one of claims 1 to 4 , wherein the first compound is a condensate of silicon oxide and / or polysiloxane. The colored metal pigment according to any one of claims 3 to 6 , wherein the second coating layer is made of a radical polymerizable resin. A first step of preparing a coated metal pigment having a first coating layer formed on the surface of the metal pigment;
An additional step of forming an organic phosphate compound layer by adsorbing an organic phosphate compound on the surface of the first coating layer of the coated metal pigment;
A second step of attaching a colored pigment to the surface of the first coating layer or the surface of the organophosphate compound layer of the coated metal pigment,
The first coating layer is composed of a radical polymerizable resin or a first compound,
The method for producing a colored metal pigment, wherein the first compound is an oxide or hydroxide of at least one element selected from the group consisting of Al, Si, Ti, Cr, Zr, Mo, and Ce. Coating composition obtained by blending a colored metallic pigment according to any one of claims 1-7.