JP6218281B2 - Resin-attached metal pigment - Google Patents

Description

  The present invention relates to a resin-attached metal pigment.

Conventionally, aluminum pigments have been used for metallic paints, printing inks, plastics kneading, and the like for the purpose of obtaining a cosmetic effect that emphasizes a metallic feeling.
However, aluminum pigments that have not been subjected to any surface treatment have a high metallic feel and design, while depending on the resin system of the paint or printing ink, the adhesion to the resin in the coating film is low. When the adhesion test is carried out, there is a drawback that a large amount is peeled off.

As a method for improving the adhesion of the aluminum pigment as described above, a method of applying a predetermined surface treatment to the aluminum pigment has been proposed.
For example, Patent Document 1 gives a metallic coating film that is excellent in adhesion to a resin when used as a pigment for paints and printing inks while maintaining the excellent metallic luster and design of aluminum pigments. Aluminum pigments that can be produced and methods for their production are disclosed.

JP 2002-226733 A

  However, in recent years, the demand for aluminum pigments has further increased, and in addition to having excellent metallic luster, designability, and adhesion to resin, it is also required to have excellent concealment with respect to the base. It has become.

  Therefore, in the present invention, it is possible to form a metallic coating film that has excellent metallic luster, designability, and adhesion to a resin, and also has excellent concealment properties with respect to the ground in view of the above-mentioned problems of the prior art. An object of the present invention is to provide a resin-attached metal pigment.

As a result of intensive studies to solve the above problems, the inventors of the present invention contain (A) 100 parts by mass of a metal pigment and (B) 0.1 to 2 parts by mass of a resin. The present invention is completed by finding that the resin-attached metal pigment using the above-mentioned has excellent metallic luster, designability, and adhesion to the resin, and can also exhibit excellent concealment with respect to the base. It came to.
That is, the present invention is as follows.

[1]
(A) Metal pigment: 100 parts by mass;
(B) Resin: 0.1 to 2 parts by mass;
A resin-attached metal pigment containing
The (B) resin is
(C) is a reaction of a radical polymerizable monomer and / or oligomer,
(C) The radically polymerizable monomer and / or oligomer is a resin-attached metal pigment containing 85% by mass or more of a radically polymerizable unsaturated carboxylic acid having 10 or less carbon atoms.
[2]
The resin-attached metal pigment according to [1], wherein the (A) metal pigment is an aluminum pigment.
[3]
A paint containing the resin-attached metal pigment according to [1] or [2].
[4]
An ink containing the resin-attached metal pigment according to [1] or [2].

  ADVANTAGE OF THE INVENTION According to this invention, the resin adhesion metal pigment which can form the metallic coating film which has the outstanding metallic luster, design property, and adhesiveness, and was excellent also in the concealment property with respect to the foundation | substrate is obtained.

  Hereinafter, a mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be appropriately modified within the scope of the gist.

[Resin-attached metal pigment]
The resin-attached metal pigment of this embodiment is
(A) Metal pigment: 100 parts by mass;
(B) Resin: 0.1 to 2 parts by mass;
Containing.
The (B) resin is
(C) is a reaction of a radical polymerizable monomer and / or oligomer,
(C) The radically polymerizable monomer and / or oligomer contains a radically polymerizable unsaturated carboxylic acid having 10 or less carbon atoms and exceeding 80% by mass.

The resin-attached metal pigment of this embodiment contains (A) a metal pigment and (B) a resin.
“Adhesion” of a resin-attached metal pigment does not only mean that the metal pigment and the resin are mixed, but also means that there is an interaction between the “metal pigment” and the “resin”. To do.
Examples of the interaction include a chemical bond, a hydrogen bond, an ionic bond, and a van der Waals force.
In addition, about adhesion of resin with respect to a metal pigment, it can confirm with the following method, for example.
Dispersing the metal pigment in an organic solvent and filtering removes the resin not attached to the metal pigment, and then volatilizes the solvent to obtain particles with the resin attached to the metal pigment. (E1).
Next, (E1) is processed in an electric furnace or the like to remove the resin adhering to the metal pigment, and only the metal pigment is used (E2).
By calculating the mass difference between (E1) and (E2), the presence or absence of resin adhesion can be confirmed.
The conditions for removing the resin adhering to the metal pigment in an electric furnace or the like vary depending on the molecular weight of the resin and the crosslink density. For example, there is a method of performing a treatment for 2 hours under a temperature condition of 350 ° C. .

((A) metal pigment)
The (A) metal pigment used for the resin-attached metal pigment of the present embodiment is not limited to the following, but includes, for example, base metal powders such as aluminum, zinc, iron, magnesium, copper, nickel, and the like. The alloy powder is mentioned.
In particular, aluminum powder frequently used as a metallic pigment is preferable.
As the metal pigment (A), those having surface properties, particle sizes, and shapes required for metallic pigments such as surface gloss, whiteness, and glitter are preferable.
(A) Examples of the shape of the metal pigment include various shapes such as a granular shape, a plate shape, a lump shape, and a scale shape, but in order to impart an excellent metallic feeling and luminance to the coating film, the shape should be a scale shape. Is preferred. For example, those having a thickness in the range of 0.001 to 1 μm and having a length or width in the range of 1 to 100 μm are preferable.
(A) It is preferable that the aspect ratio of a metal pigment exists in the range of 10-20000. Here, the aspect ratio is a value obtained by dividing the average major axis of the scaly metal pigment by the average thickness of the metal pigment.
In addition, when aluminum powder is used as the metal pigment (A), the purity of the aluminum powder is not particularly limited. However, when used for paint, the purity is preferably 99.5% or more.
(A) Although a metal pigment can be obtained by a well-known method, for example, the manufacturing method described in international publication WO99 / 54074, it is usually marketed in the paste state and can also be used.

((B) resin)
The (B) resin used for the resin-attached metal pigment of this embodiment is obtained by reacting (C) a radical polymerizable monomer and / or oligomer.
The radically polymerizable monomer and / or oligomer contains a radically polymerizable unsaturated carboxylic acid having 10 or less carbon atoms and exceeding 80% by mass. Thereby, coexistence of adhesion and concealment is achieved.
The content of the radical polymerizable unsaturated carboxylic acid having 10 or less carbon atoms in the radical polymerizable monomer and / or oligomer is preferably 85% by mass or more, and more preferably 90% by mass or more.

  Examples of the radical polymerizable unsaturated carboxylic acid having 10 or less carbon atoms include, but are not limited to, for example, acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, maleic anhydride, Or the half ester of dibasic acids, such as itaconic acid, maleic acid, and fumaric acid, etc. are mentioned, Among these, acrylic acid is preferable from an adhesive viewpoint.

  In addition, the radical polymerizable monomer and / or oligomer preferably has one or more double bonds in the molecule from the viewpoint of reactivity.

The radically polymerizable monomer and / or oligomer other than the radically polymerizable unsaturated carboxylic acid having 10 or less carbon atoms is not particularly limited, and conventionally known monomers can be used.
Although not limited to the following, for example, acrylic acid ester, methacrylic acid ester, aromatic vinyl compound, vinyl cyanide, amide group-containing vinyl monomer, hydroxyl group-containing vinyl monomer, epoxy group And a vinyl monomer having a silyl group, a carbonyl group-containing vinyl monomer, an anionic vinyl monomer, a mono- or diester of phosphoric acid or phosphonic acid, and a silyl group.

Examples of the (meth) acrylic acid ester include, but are not limited to, for example, a (meth) acrylic acid alkyl ester having 1 to 50 carbon atoms in the alkyl part, and an ethylene oxide group having 1 to 100 carbon atoms. (Poly) oxyethylene di (meth) acrylate etc. are mentioned.
Specific examples of (meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and methyl (meth) acrylate. Examples include cyclohexyl, cyclohexyl (meth) acrylate, lauryl (meth) acrylate, dodecyl (meth) acrylate, and the like.

Specific examples of (poly) oxyethylene di (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, diethylene glycol methoxy (meth) acrylate, tetraethylene glycol di (meth) acrylate Etc.
In addition, trimethylolpropane tri (meth) acrylate, tetramethylolpropane tetra (meth) acrylate, di-trimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, di-pentaerythritol hexa (meth) acrylate, Examples thereof include di-pentaerythritol penta (meth) acrylate and di-pentaerythritol penta (meth) acrylate monopropionate.
In the present specification, (meth) acrylic is a simple description of methacrylic or acrylic.

  Further, the hydroxyl group-containing vinyl monomer is not limited to the following, and examples thereof include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 3-hydroxypropyl (meta). ) Hydroxyalkyl esters of (meth) acrylic acid such as acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and di-2-hydroxyethyl fumarate , Mono-2-hydroxyethyl monobutyl fumarate, allyl alcohol, (poly) oxyethylene (meth) acrylate having 1 to 100 ethylene oxide groups, and (poly) oxy having 1 to 100 propylene oxide groups Propylene (meth) acrylate, and (Manufactured by Daicel Chemical Industries, Ltd., trade name of caprolactone addition monomer) "PLACCEL FM, FA monomer" or other alpha, such as hydroxyalkyl esters of β- ethylenically unsaturated carboxylic acid.

  Specific examples of the (poly) oxyethylene (meth) acrylate include ethylene glycol (meth) acrylate, ethylene glycol methoxy (meth) acrylate, diethylene glycol (meth) acrylate, diethylene glycol methoxy (meth) acrylate, (meth ) Tetraethylene glycol acrylate, tetraethylene glycol methoxy (meth) acrylate, and the like.

  Specific examples of (poly) oxypropylene (meth) acrylate include propylene glycol (meth) acrylate, propylene glycol methoxy (meth) acrylate, dipropylene glycol (meth) acrylate, dimethoxy meth (meth) acrylate. Examples include propylene glycol, tetrapropylene glycol (meth) acrylate, and tetrapropylene glycol methoxy (meth) acrylate.

  Examples of the epoxy group-containing vinyl monomer include, but are not limited to, glycidyl (meth) acrylate, allyl glycidyl ether, allyl dimethyl glycidyl ether, and the like.

  Examples of mono- or diesters of phosphoric acid or phosphonic acid include, but are not limited to, for example, 2-methacryloyloxyethyl phosphate, di-2-methacryloyloxyethyl phosphate, tri-2-methacryloyloxy Ethyl phosphate, 2-acryloyloxyethyl phosphate, di-2-acryloyloxyethyl phosphate, tri-2-acryloyloxyethyl phosphate, diphenyl-2-acryloyloxyethyl phosphate, dibutyl-2-methacryloyloxyethyl phosphate , Dioctyl-2-acryloyloxyethyl phosphate, 2-methacryloyloxypropyl phosphate, bis (2-chloroethyl) vinylphosphonate, diallyldibutylphosphonosuccinate, 2-methacryloyloxy Chiruhosufeto, and a 2-acrobatic acetoxyphenyl ethyl phosphate.

  Examples of the vinyl monomer having a silyl group include, but are not limited to, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3- (Meth) acryloyloxypropylmethyldimethoxysilane, 3- (meth) acryloyloxypropyltri-n-propoxysilane, 3- (meth) acryloyloxypropyltriisopropoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxy Examples thereof include silane and 2-trimethoxysilylethyl vinyl ether.

  In addition, examples of the radical polymerizable monomer and / or oligomer other than the radical polymerizable unsaturated carboxylic acid having 10 or less carbon atoms include olefins such as (meth) acrylamide, ethylene, propylene, isobutylene; Halenes such as dienes, vinyl chloride, vinylidene chloride, tetrafluoroethylene, chlorotrifluoroethylene; vinyl acetate, vinyl propionate, vinyl n-butyrate, vinyl benzoate, vinyl p-t-butylbenzoate Carboxylic acid vinyl esters such as vinyl pivalate, vinyl 2-ethylhexanoate, vinyl versatate, vinyl laurate; isopropenyl acetates such as isopropenyl acetate and isopropenyl propionate; ethyl vinyl ether, isobutyl vinyl Vinyl ethers such as ether and cyclohexyl vinyl ether; aromatic vinyl compounds such as styrene and vinyl toluene; allyl esters such as allyl acetate and allyl benzoate; allyl ethers such as allyl ethyl ether and allyl phenyl ether; (Meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloyloxy-1,2,2,6,6-pentamethylpiperidine, perfluoromethyl (meth) acrylate, perfluoropropyl (Meth) acrylate, perfluoropropylmethyl (meth) acrylate, vinyl pyrrolidone, allyl (meth) acrylate, etc., and combinations thereof are mentioned.

The resin-attached metal pigment of the present embodiment contains (A) 100 parts by mass of the metal pigment and (B) 0.1 to 2 parts by mass of the resin.
(B) Content of resin shall be 0.1 mass part or more from an adhesive viewpoint, and shall be 2 mass parts or less from a glossy and design viewpoint.
The content of (B) resin is preferably 0.2 to 1.9 parts by mass with respect to 100 parts by mass of (A) metal pigment.

(Polymerization initiator)
When producing the resin-attached metal pigment of this embodiment, it is preferable to use a polymerization initiator.
A method for producing the resin-attached metal pigment of this embodiment will be described later.
The polymerization initiator is generally known as a radical generator, and the type thereof is not particularly limited.
Examples of the polymerization initiator include, but are not limited to, peroxides such as benzoyl peroxide, lauroyl peroxide, bis- (4-t-butylcyclohexyl) peroxydicarbonate, and 2,2′-azobis. -Azo compounds such as isobutyronitrile and 2,2'-azobis-2,4-dimethylvaleronitrile.
Although the usage-amount of a polymerization initiator is each specifically adjusted by the reaction rate of (C) radically polymerizable monomer and / or oligomer, (A) It is 0.1 with respect to 100 mass parts of metal pigments. Mass parts to 25 parts by mass are preferred.

(Other ingredients)
As will be described later, the resin-attached metal pigment of the present embodiment is obtained by dispersing the metal pigment in a predetermined organic solvent, and then adjusting the molecular weight of the reaction product together with the above-described (C) radical polymerizable monomer and / or oligomer. A chain transfer agent may be added for the purpose of control.
Examples of the chain transfer agent include, but are not limited to, alkyl mercaptans such as n-octyl mercaptan, n-dodecyl mercaptan, and t-dodecyl mercaptan; aromatics such as benzyl mercaptan and dodecyl benzyl mercaptan. Group mercaptans; thiocarboxylic acids such as thiomalic acid or salts thereof, or alkyl esters thereof, or polythiols, diisopropylxanthogen disulfide, di (methylenetrimethylolpropane) xanthogen disulfide and thioglycol, and α-methylstyrene And allyl compounds such as dimers.
The amount of these chain transfer agents used is preferably in the range of 0.001 to 30% by mass, more preferably 0.05 to 10% by mass relative to the (B) resin.

[Method for producing resin-attached metal pigment]
The resin-attached metal pigment of the present embodiment is obtained by dispersing an untreated metal pigment in an organic solvent and then heating and adding (C) a radical polymerizable monomer and / or oligomer and a polymerization initiator while stirring. It can manufacture by making it react.
The organic solvent may be (A) inert as long as it is inert to the metal pigment, and is not limited to the following. For example, aliphatic hydrocarbons such as hexane, heptane, octane, and mineral spirits; benzene, toluene Aromatic hydrocarbons such as xylene and solvent naphtha; ethers such as tetrahydrofuran and diethyl ether; alcohols such as ethanol, 2-propanol and butanol; esters such as ethyl acetate and butyl acetate; ethylene glycol monoethyl ether Examples include cellosolves.

The mass concentration of the (A) metal pigment in the organic solvent is preferably 0.1 to 40% by mass, more preferably 1 to 35% by mass.
0.1 mass% or more is preferable from the viewpoint of reaction rate, and 40 mass% or less is preferable from the viewpoint of dispersibility.

When the untreated (A) metal pigment is dispersed in an organic solvent, the mixture is heated, and the (C) radical polymerizable monomer and / or oligomer is added with stirring, from the viewpoint of productivity. A radically polymerizable unsaturated carboxylic acid having 10 or less carbon atoms is added as a first stage, and (C) a radically polymerizable monomer other than the radically polymerizable unsaturated carboxylic acid having 10 or less carbon atoms and / or as a second stage. It is preferred to add oligomers.
The second stage may contain a radically polymerizable unsaturated carboxylic acid having 10 or less carbon atoms, and conversely when the resin is composed of only a radically polymerizable unsaturated carboxylic acid having 10 or less carbon atoms, The second stage is not necessary.

(C) When a polymerization initiator is used in the polymerization reaction of the radically polymerizable monomer and / or oligomer, the timing of adding the polymerization initiator is not particularly limited, but (C) radical It is preferable to add at the same time and / or after the polymerizable monomer and / or oligomer.
The temperature at which the polymerization initiator is added is not particularly limited as long as the polymerization reaction of the (C) radical polymerizable monomer and / or oligomer occurs, but is preferably 60 ° C to 150 ° C. Further, it is preferable to add and react in an inert gas atmosphere such as nitrogen or helium in order to increase the reaction efficiency.

In addition, in the reaction of the (C) radical polymerizable monomer and / or oligomer, a solvent can be added or substituted as necessary.
As the organic solvent, an ester-based solvent is preferable from the viewpoint of environmental load and drying property.
In particular, when propyl acetate is used, the amount of residual solvent is small even when the drying temperature is low, which is preferable from the viewpoint of adhesion and odor.
(A) A metal pigment becomes large in particle diameter by reacting with (B) resin. The difference in the average particle diameter before and after the reaction is preferably 2.5 μm or less, more preferably 2.0 μm or less, from the viewpoint of concealment of the resin-attached metal pigment of the present embodiment with respect to the base.

[Usage of resin-attached metal pigment]
The resin-attached metal pigment of this embodiment can be used as a pigment for paint or ink.
As the paint or ink, either a solvent type or an aqueous type can be used.
When the resin-attached metal pigment of this embodiment is used in solvent-type paints and inks, the paint or ink resin used in conventional metallic paints and metallic inks should be used as the paint resin or ink resin. Can do. The paint or ink resin is not limited to the following, but examples include acrylic resins, alkyd resins, oil-free alkyd resins, vinyl chloride resins, urethane resins, melamine resins, unsaturated polyester resins, urea resins. , Cellulose resin, epoxy resin, fluororesin and the like.
These may be used alone or in combination of two or more.

  When the resin-attached metal pigment of the present embodiment is used as a solvent-type paint and ink pigment, the amount of the resin-attached metal pigment used is 0.1 to 300 parts by weight with respect to 100 parts by weight of the paint or ink resin. A mass part is preferable and 0.2-200 mass parts is more preferable. 0.1 mass parts or more is preferable from the viewpoint of metallic gloss, and 300 mass parts or less is preferable from the viewpoint of physical properties of the coating film.

Solvent-type paints and ink diluents are not limited to the following, but include, for example, aromatic compounds such as toluene and xylene; aliphatic compounds such as hexane, heptane, and octane; ethanol, butanol, etc. Examples include alcohols; esters such as ethyl acetate and butyl acetate; ketones such as methyl ethyl ketone; chlorine compounds such as trichloroethylene; and cellosolves such as ethylene glycol monoethyl ether. These diluents may be used alone or in a combination of two or more.
The composition of the diluent may be appropriately determined in consideration of solubility in paint and ink resins, coating film formation characteristics, coating workability, and the like.

  In addition, for paints and inks, pigments, dyes, wetting agents, dispersants, anti-splitting agents, leveling agents, slip agents, anti-skinning agents, anti-gelling agents, antifoaming agents commonly used in the paint industry An additive such as an agent may be further added.

The paint and ink can also be used as a water-based paint by using a water-based paint resin.
However, when an aluminum pigment is used as the metal pigment (A), it may react with water in the water-based paint and ink. In such a case, it is necessary to add a reaction inhibitor.
Here, the resin for water-based paints is a water-soluble resin or a water-dispersible resin, and may be used alone or in a mixture of two or more. The type may be appropriately selected depending on the purpose and application, and is not particularly limited, but for paints, water-based paint resins such as acrylic, acrylic-melamine, polyester, and polyurethane are generally used. Of these, acrylic-melamine is most commonly used.

  When used as a water-based paint or ink, the amount of the resin-attached metal pigment of this embodiment is preferably 0.1 to 300 parts by weight with respect to 100 parts by weight of the water-based paint resin. It is more preferable that it is 2 mass parts-200 mass parts. From the viewpoint of obtaining metallic luster, it is preferably 0.1 parts by mass or more, and from the viewpoint of physical properties of the coating film, it is preferably 300 parts by mass or less.

  Examples of various additives include dispersants, thickeners, sagging inhibitors, antifungal agents, ultraviolet absorbers, film forming aids, surfactants, other organic solvents, water, etc. Any of those that can be generally used and that does not impair the effects of the present invention can be used, and it is preferably added in an amount that does not impair the effects of the present invention.

[Painting method]
As a coating method using a paint or ink containing the resin-attached metal pigment of the present embodiment, a known method can be applied.
For example, spraying method, flow coating method, roll coating method, brush coating method, dip coating method, spin coating method, screen printing method, casting method, gravure printing method, flexographic printing method and the like can be mentioned.
Further, after coating, it is possible to carry out heat treatment at 20 to 500 ° C., more preferably 40 to 250 ° C., ultraviolet irradiation or the like, if desired. Moreover, it is also possible to apply | coat a coating material with respect to the base material heated at 40-250 degreeC.

[Use]
The resin-attached metal pigment of this embodiment can be used for painting for automobiles, general household appliances, information household appliances represented by mobile phones, or predetermined printing applications.
A base material made of a predetermined material such as a metal such as iron or magnesium alloy, or plastic can be coated and printed, and high design properties can be exhibited.

  Hereinafter, the present invention will be described in detail with reference to specific examples and comparative examples, but the present invention is not limited to the following examples.

In Examples and Comparative Examples, various physical properties were measured by the following methods.
[Method for measuring physical properties]
<1. Average particle diameter>
Made by Shimadzu Corporation; using SALD-2200 (laser diffraction particle size distribution measuring device), resin-attached metal pigments produced by Examples and Comparative Examples described later, and aluminum paste (Asahi Kasei Chemicals Corporation, GX-4100) ) Was measured.

<2. Resin amount>
The amount of resin relative to 100 parts by mass of component (A) is (C) acrylic acid and trimethylol when the mass (2000 g × 0.74) of the nonvolatile content of the aluminum paste used as component (A) is 100 parts by mass. The total mass (parts by mass) of propanetrimethacrylate was calculated.

<3. (C) Amount of radically polymerizable unsaturated carboxylic acid having 10 or less carbon atoms in component (mass%)>
The amount of the radical polymerizable unsaturated carboxylic acid having 10 or less carbon atoms in the component (C) was calculated by [acrylic acid / (acrylic acid + trimethylolpropane trimethacrylate)] × 100.

<2. Adhesion>
Cellotape (registered trademark: manufactured by Nichiban Co., Ltd., width: 18 mm) was brought into close contact with the coating film, pulled at an angle of 90 °, and the degree of peeling of the aluminum pigment particles was visually observed.
A: No peeling (less than 5%)
○: almost no peeling (less than 10%)
Δ: Peeling is observed (less than 50%)
×: Half or more peeling (50% or more)

<3. Concealment>
Using a haze meter HZ-V3 manufactured by Suga Test Instruments Co., Ltd., the total light transmittance (Tt) was evaluated.
The smaller the value, the better the concealment.

<4. Metal gloss>
A 60 degree gloss (both incident angle and reflection angle is 60 degrees) is measured using a gloss meter (manufactured by Suga Test Instruments Co., Ltd., digital variable gloss meter UGV-5D). G 'is a measured value of 60 ° gloss of a coated plate using the metal pigment of the present invention, and G is a measured value of 60 ° gloss of a coated plate similarly produced using a metal pigment not coated with a resin. R was determined by the following equation.
R = (G ′ / G) × 100
Depending on the value of the gloss retention rate R, the evaluation was as follows.
The larger the numerical value, the better, and a value of 70 or more was judged to be practically good.
◎ (excellent): 90 or more ○ (good): less than 90 to 80 or more △ (possible): less than 80 to 70 or more × (impossible): less than 70

[Example 1]
2000 g of commercially available aluminum paste (GX-4100 “average particle size 10 μm, nonvolatile content 74 mass%” manufactured by Asahi Kasei Chemicals Co., Ltd.) and mineral spirit 8300 g were charged into a 20 L reaction tank.
And it stirred, introducing nitrogen gas, and raised the temperature in a system to 70 degreeC.
Next, 24.0 g of acrylic acid was added and stirring was continued for 30 minutes.
Thereafter, a liquid consisting of 3.0 g of trimethylolpropane trimethacrylate, 3.0 g of 2,2′-azobis-2,4-dimethylvaleronitrile, and 1200 g of mineral spirit was added at a rate of about 10 g / min with a metering pump, After completion, the system was stirred for a total of 6 hours while maintaining the temperature in the system at 70 ° C.
After completion of the reaction, the mixture was naturally cooled, and the slurry was filtered to obtain a resin-attached aluminum paste.
According to JIS-K-5910, the measured non-volatile content of the resin-attached aluminum paste was 50% by mass.
The difference between the average particle diameter before and after the reaction, that is, the average particle diameter of the resin-attached aluminum paste and the average particle diameter of the commercially available aluminum paste was 1.2 μm.
10 g of polyurethane resin (Samprene IB-1700D (manufactured by Sanyo Chemical Industries)), 4 g of ethyl acetate, 4 g of methyl ethyl ketone, and 4 g of isopropanol are added to 2 g of the obtained resin-attached aluminum paste, and stirred with a magnetic stirrer for 10 minutes. A metallic ink was obtained.
The obtained metallic ink was applied to a PET film with a bar coater so as to have a dry film thickness of 3 μm.
When the obtained coating film was evaluated after storage for 24 hours under a temperature condition of 50 ° C., the adhesion was good and the hiding property was good (Tt 15%).
Further, the gloss retention of the coating film was very good (◎).

[Example 2]
100 g of propyl acetate was added to 10 g of the resin-plated aluminum paste obtained in Example 1 and stirred for 10 minutes.
Then, the aluminum paste which substituted mineral spirit with the propyl acetate solvent was obtained by performing filtration.
According to JIS-K-5910, the measured non-volatile content of the resin-attached aluminum paste was 50% by mass.
Using the obtained resin-adhered aluminum paste, a metallic ink was obtained in the same manner as in [Example 1].
The obtained metallic ink was applied to a PET film with a bar coater so as to have a dry film thickness of 3 μm.
When the obtained coating film was evaluated after storage for 24 hours at a temperature of 50 ° C., the adhesion was very good and the hiding property was good (Tt 15%).
Further, the gloss retention of the coating film was very good (◎).

[Example 3, Comparative Examples 1-2]
The amounts of acrylic acid, trimethylolpropane trimethacrylate, and 2,2′-azobis-2,4-dimethylvaleronitrile were changed.
Other conditions were the same as in Example 1 to produce a resin-attached aluminum paste, and a metallic ink was produced using the resin-attached aluminum paste.
The obtained metallic ink was applied to a PET film with a bar coater so as to have a dry film thickness of 3 μm.
The obtained coating film was evaluated after storage for 24 hours under a temperature condition of 50 ° C.
The evaluation results are shown in Table 1 below.
In Table 1, “MS” represents mineral spirit.

The evaluation results of Examples 1 to 3 and Comparative Examples 1 and 2 are shown in Table 1 below.
In Table 1, as a reference example, physical properties of the aluminum paste before the surface treatment with the resin are shown.
The resin-attached metal pigments of Examples 1 to 3 had excellent metallic luster, designability, and adhesion, and were able to obtain a high hiding property equivalent to the aluminum paste before treatment.

  The resin-attached metal pigment of this embodiment has industrial applicability as a paint or ink for automobiles, general household appliances, information household appliances represented by mobile phones, or as a printing material for a predetermined substrate. .

Claims (4)

(A) Metal pigment: 100 parts by mass;
(B) Resin: 0.1 to 2 parts by mass;
A resin-attached metal pigment containing
The (B) resin is
(C) is a reaction of a radical polymerizable monomer and / or oligomer,
(C) The radically polymerizable monomer and / or oligomer is a resin-attached metal pigment containing 85% by mass or more of a radically polymerizable unsaturated carboxylic acid having 10 or less carbon atoms.   The resin-attached metal pigment according to claim 1, wherein the (A) metal pigment is an aluminum pigment.   The coating material containing the resin adhesion metal pigment of Claim 1 or 2.   An ink containing the resin-attached metal pigment according to claim 1.