JP2017057309A - Resin-adhered aluminum pigment, coating material and ink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin-adhered aluminum pigment capable of forming a metallic coating film having excellent initial adhesion, designability and adhesion to a resin, as well as an excellent property to conceal a substrate.SOLUTION: A resin-adhered aluminum pigment includes: an aluminum pigment (A); and a resin compound (B) adhered to the aluminum pigment (A) and being a polymer of a radical-polymerizable monomer and/or an oligomer having one or more double bonds in the molecule. When a solid content after washing the resin-adhered aluminum pigment with chloroform is dispersed in dimethylformamide and agitated at 70°C for 24 hours, a mass ratio, (b)/(a), of an insoluble solid content (a) and a soluble content (b) is 0.0001-0.1. A weight average molecular weight of the soluble content (b) is 1,000-30,000 in terms of PMMA as measured by GPC.SELECTED DRAWING: None

Description

  The present invention relates to a resin-attached aluminum pigment, and a paint and an ink containing the resin-attached aluminum 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. For example, in printing ink applications, it is required to increase the printing speed in order to improve productivity. In order not to occur, improvement of adhesion (initial adhesion) before the ink is completely dried has been a problem. Furthermore, in addition to having excellent design properties and adhesion to a resin, it is also required to have excellent concealment with respect to the base.

  Therefore, in the present invention, in view of the above-described problems of the prior art, a metallic coating film having excellent initial adhesion, design properties, and adhesion to a resin and excellent in concealment with a base is formed. It is an object of the present invention to provide a resin-attached aluminum pigment that can be used.

As a result of intensive studies to solve the above problems, the present inventors have (A) an aluminum pigment and (B) a predetermined resin compound, and the solid content after washing with chloroform is dispersed in dimethylformamide. (A) Mass ratio (b) / (a) of insoluble solid content to (b) dissolved solid content is within a predetermined range, and (b) the weight average molecular weight of dissolved solid content is within a predetermined numerical range. The present inventors have found that a resin-adhered aluminum pigment has excellent initial adhesiveness, designability, and adhesiveness with a resin, and can exhibit an excellent effect of concealment with respect to a base, and has completed the present invention.
That is, the present invention is as follows.

[1]
(A) an aluminum pigment;
(A) a resin compound attached to the aluminum pigment, (B) a radically polymerizable monomer and / or oligomer polymer having one or more double bonds in the molecule;
Including,
When the solid content after washing with chloroform was dispersed in dimethylformamide and stirred at 70 ° C. for 24 hours, the mass ratio (b) / (a) of (a) insoluble solid content and (b) dissolved solid content was 0. .0001-0.1,
(B) A resin-attached aluminum pigment having a PMMA-converted weight average molecular weight of 1,000 to 30,000, as measured by GPC, of the dissolved solid content.
[2]
A paint containing the resin-attached aluminum pigment according to [1].
[3]
An ink containing the resin-attached aluminum pigment according to [1].

  ADVANTAGE OF THE INVENTION According to this invention, the resin adhesion aluminum pigment which has the outstanding initial adhesiveness, the designability, and adhesiveness with resin, and can form the metallic coating film excellent also in the concealment property with respect to a 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 embodiment is an example for explaining the present invention, and is not limited to the following description. The present invention can be appropriately modified within the scope of the gist.

[Resin-attached aluminum pigment]
The resin-attached aluminum pigment of this embodiment is
(A) an aluminum pigment;
(B) a resin compound attached to the aluminum pigment, which is a polymer of a radical polymerizable monomer and / or oligomer having one or more double bonds in the molecule;
Including,
When the solid content after washing with chloroform was dispersed in dimethylformamide and stirred at 70 ° C. for 24 hours, the mass ratio (b) / (a) of (a) insoluble solid content and (b) dissolved solid content was 0. .0001-0.1,
The weight average molecular weight in terms of PMMA measured by GPC of the dissolved solid content (b) is 1,000 or more and 30,000 or less.

The resin-attached aluminum pigment of this embodiment contains (A) an aluminum pigment and (B) a resin compound.
Specifically, (A) an aluminum pigment, and (B) a resin compound attached to the aluminum pigment, which is a polymer of a radically polymerizable monomer and / or oligomer having one or more double bonds in the molecule; The solid content after washing with chloroform was dispersed in dimethylformamide and stirred for 24 hours at 70 ° C. The mass ratio of (a) insoluble solid content and (b) dissolved solid content (b) / (a) However, it is 0.0001-0.1, The weight average molecular weight of PMMA conversion measured by GPC of said (b) melt | dissolution solid content is 1,000 or more and 30,000 or less.
The “adhesion” does not simply mean that (A) the aluminum pigment and (B) the resin compound are mixed, but there is an interaction between the “aluminum metal” and the “resin compound”. It means a certain state.
Examples of the interaction include a chemical bond, a hydrogen bond, an ionic bond, and a van der Waals force.

((A) Aluminum pigment)
As the (A) aluminum pigment used for the resin-attached aluminum pigment of the present embodiment, those having surface properties, particle sizes, and shapes required for metallic pigments such as surface gloss, whiteness, and glitter are suitable.
The shape may be various shapes such as a granular shape, a plate shape, a block shape, and a scale shape, but in order to give an excellent metallic feeling and luminance to the coating film, a scale shape is preferable.
(A) The aluminum pigment has a thickness in the range of 0.001 to 1 μm, and preferably has a length or width in the range of 1 to 100 μm.
(A) It is preferable that the aspect ratio of an aluminum pigment exists in the range of 10-20000.
Here, the aspect ratio is a value obtained by dividing the average major axis of (A) the aluminum pigment by the average thickness of the aluminum pigment.
Moreover, the purity of the (A) aluminum pigment is not particularly limited, but the purity of the aluminum pigment used for coating is preferably 99.5% or more.
(A) Although an aluminum pigment can be obtained by a well-known method, for example, the manufacturing method described in international publication gazette WO99 / 54074, it is usually marketed in the state of a paste, and this can also be used for it.

((B) resin compound)
(B) The resin compound is a polymer obtained by polymerizing a radical polymerizable monomer and / or oligomer having one or more double bonds in the molecule.

It does not specifically limit as a radically polymerizable monomer and / or oligomer, A conventionally well-known thing can be used.
Examples of the radical polymerizable monomer and / or oligomer include, but are not limited to, for example, (meth) acrylic acid, (meth) acrylic acid ester, aromatic vinyl compound, and vinyl cyanides. Amide group-containing vinyl monomers, hydroxyl group-containing vinyl monomers, epoxy group-containing vinyl monomers, carbonyl group-containing vinyl monomers, anionic vinyl monomers, mono- or diesters of phosphoric acid or phosphonic acid And vinyl monomers having a silyl group.

  In the present specification, (meth) acrylic is a simple description of methacrylic or acrylic.

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 a number of ethylene oxide groups of 1 to 100. (Poly) oxyethylene di (meth) acrylate etc. are mentioned.
Examples of (meth) acrylic acid esters include, but are not limited to, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, (meth) acrylic acid 2 -Ethylhexyl, methyl cyclohexyl (meth) acrylate, cyclohexyl (meth) acrylate, lauryl (meth) acrylate, dodecyl (meth) acrylate, and the like.
Examples of (poly) oxyethylene di (meth) acrylate include, but are not limited to, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, diethylene glycol methoxy (meth) acrylate, Examples include tetraethylene glycol di (meth) acrylate.
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, di-pentaerythritol penta (meth) acrylate monopropionate, and the like.

  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 and (poly) oxyethylene mono (meth) acrylate having 1 to 100 ethylene oxide groups, 1 to 100 (poly) propylene oxide groups Oxypropylene mono (meth) acrylate Furthermore, "PLACCEL FM, FA monomer" (manufactured by Daicel Chemical Industries, Ltd., trade name of caprolactone addition monomer) and other alpha, hydroxyalkyl esters of β- ethylenically unsaturated carboxylic acid and the like.

Examples of the (poly) oxyethylene mono (meth) acrylate include, but are not limited to, ethylene glycol (meth) acrylate, ethylene glycol methoxy (meth) acrylate, diethylene glycol (meth) acrylate, Examples include methoxy (meth) acrylic acid diethylene glycol, (meth) acrylic acid tetraethylene glycol, and methoxy (meth) acrylic acid tetraethylene glycol.

  In addition, the (poly) oxypropylene mono (meth) acrylate is not limited to the following, but, for example, propylene glycol (meth) acrylate, propylene glycol methoxy (meth) acrylate, dimethacrylate (meth) acrylate Examples include propylene glycol, dipropylene glycol methoxy (meth) acrylate, 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.

  The mono- or diesters of phosphoric acid or phosphonic acid are not limited to the following, but examples include 2-methacryloyloxyethyl phosphate, di-2-methacryloyloxyethyl phosphate, tri-2- Methacryloyloxyethyl phosphate, 2-acryloyloxyethyl phosphate, di-2-acryloyloxyethyl phosphate, tri-2-acryloyloxyethyl phosphate, diphenyl-2-acryloyloxyethyl phosphate, dibutyl-2-methacryloyl Roxyethyl phosphate, dioctyl-2-acryloyloxyethyl phosphate, 2-methacryloyloxypropyl phosphate, bis (2-chloroethyl) vinylphosphonate, diallyldibutylphosphonosuccinate, 2-methacrylic Gray ethyl phosphate, 2-acryloyl acetoxyphenyl ethyl phosphate.

  Further, the vinyl monomer having a silyl group is not limited to the following, but examples thereof include 3- (meth) acryloxypropyltrimethoxysilane and 3- (meth) acryloxypropyltriethoxysilane. 3- (meth) acryloyloxypropylmethyldimethoxysilane, 3- (meth) acryloyloxypropyltri-n-propoxysilane, 3- (meth) acryloyloxypropyltriisopropoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, Examples include allyltrimethoxysilane and 2-trimethoxysilylethyl vinyl ether.

In addition, the (B) resin compound is not limited to the following. For example, (meth) acrylamide, olefins such as ethylene, propylene, and isobutylene; dienes such as butadiene; vinyl chloride, vinylidene chloride fluoride Haloolefins such as vinyl, tetrafluoroethylene, chlorotrifluoroethylene; vinyl acetate, vinyl propionate, vinyl n-butyrate, vinyl benzoate, vinyl pt-butylbenzoate, vinyl pivalate, 2-ethylhexanoic acid Carboxylic acid vinyl esters such as vinyl, vinyl versatate and vinyl laurate; Carboxylic acid isopropenyl esters such as isopropenyl acetate and isopropenyl propionate; Vinyl vinyl such as ethyl vinyl ether, isobutyl vinyl ether and cyclohexyl vinyl ether Ethers; aromatic vinyl compounds such as styrene and vinyltoluene, allyl esters such as allyl acetate and allyl benzoate; allyl ethers such as allyl ethyl ether and allyl phenyl ether; and 4- (meth) acryloyloxy-2, 2,6,6, -tetramethylpiperidine, 4- (meth) acryloyloxy-1,2,2,6,6, -pentamethylpiperidine, perfluoromethyl (meth) acrylate, perfluoropropyl (meth) acrylate, Examples thereof include perfluoropropylmethyl (meth) acrylate, vinyl pyrrolidone, allyl (meth) acrylate, and the like.
(B) A resin compound may be used individually by 1 type, and may use 2 or more types together.

(Mass ratio between (a) insoluble solid and (b) dissolved solid: (b) / (a), (b) weight average molecular weight of dissolved solid)
The resin-attached aluminum pigment of this embodiment includes (A) an aluminum pigment and (B) a radically polymerizable monomer and / or oligomer having one or more double bonds in the molecule attached to the (A) aluminum pigment. And a resin compound obtained by polymerizing.
(A) Insoluble solid content and (b) dissolved solid content when the solid content after washing with chloroform of both component (A) and component (B) is dispersed in dimethylformamide and stirred at 70 ° C. for 24 hours. The mass ratio (b) / (a) is 0.0001 to 0.1, and (b) the weight average molecular weight in terms of PMMA measured by GPC of the dissolved solid content is 1,000 or more and 30,000 or less. .
By including a resin compound in the above molecular weight range, it is possible to achieve both high-dimensional design and initial adhesion.
The mass ratio (b) / (a) is preferably 0.001 to 0.08, more preferably 0.001 to 0.05.
The weight average molecular weight of the (b) dissolved solid content is preferably 2,000 to 28,000, and more preferably 3,000 to 25,000.
The mass ratio of the (a) insoluble solid content to the (b) dissolved solid content: (b) / (a) is the amount of the (B) resin compound attached to the aluminum pigment, and (B) the dissolved solid content in the resin compound. It can be controlled by adjusting the fraction ratio.
Specifically, by increasing the amount of the radical polymerizable monomer and / or oligomer in the production process of the resin-attached aluminum pigment of the present embodiment, the amount of (B) the resin compound attached to the aluminum pigment is increased. Accordingly, the mass ratio (b) / (a) can be increased. In addition, when preparing the resin compound (B) in the production process of the resin-attached aluminum pigment, the ratio of radically polymerizable monomers and / or oligomers having one or more double bonds in the molecule is reduced. Thus, the mass ratio (b) / (a) can be increased.
Moreover, the mass ratio: (b) / (a) can be increased by adjusting the weight average molecular weight of the resin compound (B) by the following adjustment method so that the weight average molecular weight is not excessively increased. it can.
In order to reduce (b) / (a), conversely, (B) reducing the adhesion amount of the resin compound to the aluminum pigment, among the radical polymerizable monomers and / or oligomers, It is effective to increase the ratio of those having one or more double bonds and to increase the weight average molecular weight of the resin compound (B).
The above-mentioned mass ratio (b) / (a) is controlled within the desired numerical range by appropriately selecting the method described above and appropriately implementing the measurement method (b) / (a) described in the examples described later. can do.
(B) The weight average molecular weight of the dissolved solids can be controlled by various known methods. For example, in the production process of the resin-attached aluminum pigment of this embodiment, (B) a chain for preparing the resin compound It can be controlled by using a transfer agent, adjusting the amount of polymerization initiator used, and further adjusting the amount of radically polymerizable monomer and / or oligomer having two or more double bonds in the molecule. .

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; 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 adjusted with the reaction rate of the radically polymerizable monomer and / or oligomer used in order to manufacture (B) resin compound, and the molecular weight of the resin compound obtained, it is not specifically limited, (A) 0.1 mass part-25 mass parts are preferable with respect to 100 mass parts of aluminum pigments.

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; fragrances such as benzyl mercaptan and dodecyl benzyl mercaptan. Mercaptans; thiocarboxylic acids such as thiomalic acid or their salts or their alkyl esters, or polythiols, diisopropylxanthogen disulfide, di (methylenetrimethylolpropane) xanthogen disulfide and thioglycol, and also α-methylstyrene Examples include allyl compounds such as dimers.
These chain transfer agents are preferably used in an amount of 0.001 to 30% by mass, more preferably 0.05 to 10% by mass, based on the total monomer of the target resin compound.

[Method for producing resin-attached aluminum pigment]
The resin-attached aluminum pigment of this embodiment is a dispersion reaction in which an untreated aluminum pigment is dispersed in an organic solvent, and then heated and stirred while adding a radical polymerizable monomer and / or oligomer and a polymerization initiator. It can manufacture by performing.

  The organic solvent is not limited to the following as long as it is inert with respect to (A) the aluminum pigment. 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) aluminum pigment in the organic solvent is preferably 0.1 to 40% by mass, more preferably 1 to 35% by mass.
From the viewpoint of reaction rate, 0.1% by mass or more is preferable, and from the viewpoint of dispersibility, 40% by mass or less is preferable.

Although there is no restriction | limiting in the addition timing of a polymerization initiator, It is preferable to add, after adding the said monomer and oligomer simultaneously with the said radically polymerizable monomer and / or oligomer.
The temperature at which the polymerization initiator is added is not particularly limited as long as the reaction proceeds, 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.
Moreover, a solvent can also be added and / or substituted as needed.
An ester 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.
The (A) aluminum pigment has a larger particle size by reacting with the (B) resin compound.
The difference in 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.

[Paint, ink]
The resin-attached aluminum pigment of this embodiment can be used as a paint or ink.
As the paint or ink, either a solvent type or an aqueous type can be used.
When the resin-adhesive aluminum resin of this embodiment is used in solvent-based paints and inks, the paint resin 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 aluminum pigment of this embodiment is used as a solvent-type paint and ink pigment, the amount of the resin-attached aluminum pigment used is 0.1 mass relative to 100 parts by mass of the resin for paint or ink. Part to 300 parts by weight, and more preferably 0.2 part to 200 parts by weight.
0.1 mass parts or more is preferable from the viewpoint of metallic luster, and 300 mass parts 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 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 You may add additives, such as an agent.

In addition, the paint and ink can be used as a water-based paint or water-based ink by using a resin for water-based paint.
However, (A) an aluminum pigment may react with water in water-based paints and inks.
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 and water-based ink, the amount of the resin-attached aluminum pigment of this embodiment is preferably 0.1 to 300 parts by weight with respect to 100 parts by weight of the paint resin, 0.2 It is more preferable that it is mass parts-200 mass parts.
From the viewpoint of metallic luster, 0.1 part by mass or more is preferable, and from the viewpoint of physical properties of the coating film, 300 part by mass or less is preferable.

  Examples of various additives include, but are not limited to, dispersants, thickeners, sagging inhibitors, antifungal agents, ultraviolet absorbers, film forming aids, surfactants, and other organic substances. A solvent, water, or the like that can be used in this field and that does not impair the effects of this embodiment may be added.

(Coating method of paint and ink)
Various known methods can be applied as a coating method of the paint or ink containing the resin-attached aluminum pigment of the present embodiment.
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, heat treatment or ultraviolet irradiation at 20 to 500 ° C., more preferably 40 to 250 ° C. may be performed. 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 aluminum 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, although a specific Example and a comparative example are given and this embodiment is described in detail, this embodiment 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)
Manufactured by Shimadzu Corporation; using an SALD-2200 (laser diffraction particle size distribution measuring device), resin-attached aluminum pigments and aluminum pastes (GX-4100 manufactured by Asahi Kasei Chemicals Co., Ltd.) manufactured according to Examples and Comparative Examples described later. The average particle size of “average particle size 10 μm, nonvolatile content 74%”) was measured.

(2. Initial adhesion)
The metallic ink obtained in each Example and Comparative Example was applied to a PET film with a bar coater so as to have a dry film thickness of 2 μm to obtain a coating film.
A sample obtained by drying the obtained coating film at 50 ° C. for 2 hours was used as an evaluation sample.
Cellotape (registered trademark: manufactured by Nichiban Co., Ltd., width: 18 mm) was closely attached to the coating film, pulled at an angle of 90 °, and the degree of peeling of the aluminum pigment particles was visually observed.
◎ No delamination was observed ○ Almost no delamination was observed △ Some delamination was observed x Remarkable delamination was observed

(3. Concealment)
The metallic ink obtained in each Example and Comparative Example was applied to a PET film with a bar coater so as to have a dry film thickness of 2 μm to obtain a coating film.
A sample obtained by drying the obtained coating film at 50 ° C. for 24 hours was used as an evaluation sample.
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 hiding property.

(4. Metal gloss)
The coating film produced similarly to the dry coating film used for evaluation in the above (3. Hiding property) was used for evaluation.
A 60 degree gloss (incident angle and reflection angle was 60 degrees) was 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 coating film using a resin-attached aluminum pigment, and G is a measured value of 60 ° gloss of a coating film prepared under the same conditions using a metal pigment to which no resin is adhered. The retention rate R was determined by the following formula.
R = (G ′ / G) × 100
Depending on the value of the gloss retention rate R, the evaluation was as follows.
A larger numerical value was judged to be 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

(5. Mass ratio of insoluble solid and dissolved solid)
10 g of the obtained resin-attached aluminum paste (resin-attached aluminum pigment) was stirred and washed with chloroform at 23 ° C. for 2 hours and filtered to remove the resin not attached to aluminum.
Furthermore, aluminum and resin were dispersed in dimethylformamide (DMF) and stirred at 70 ° C. for 24 hours.
Thereafter, the mixture was filtered and the solvent was distilled off to obtain (a) an insoluble solid content and (b) a dissolved solid content.
The mass of each component was measured and the mass ratio (b) / (a) was determined.

(6. Molecular weight of dissolved solids)
In the same step as (5. Mass ratio of insoluble solids and dissolved solids), (a) insoluble solids and (b) dissolved solids are separated, and (b) the filtrate containing dissolved solids is GPC. Analysis was performed to determine the weight average molecular weight of the dissolved solids.
The weight average molecular weight was measured as a weight average molecular weight in terms of PMMA.

[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 (resin-attached aluminum pigment).
The non-volatile content of the resin-attached aluminum paste according to JIS-K-5910 was 50% by mass.
The difference in the average particle size before and after the reaction, that is, the difference between the average particle size of the resin-attached aluminum paste and the average particle size of the commercially available aluminum paste was 1.2 μm.
The mass ratio of insoluble solids and dissolved solids of the obtained resin-adhered aluminum paste and the weight average molecular weight of the dissolved solids were measured.
(A) The mass of the insoluble solid content is 4.8 g, (b) the mass of the dissolved solid content is 0.02 g, and the ratio (b) / (a) = 0.002, the weight average molecular weight in terms of PMMA by GPC. Was 7,000. The said (b) / (a) mass ratio and the weight average molecular weight were controlled by adjusting the usage-amount of the radically polymerizable monomer which has a 2 or more double bond in a molecule | numerator.
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 6 g of the obtained resin-attached aluminum paste, and the mixture is stirred for 10 minutes with a magnetic stirrer. A metallic ink was obtained.
Using the obtained metallic ink, the initial adhesion of the coating film, the concealing property of the coating film, and the metallic gloss were evaluated. The evaluation results are shown in Table 1 below.

[Examples 2-7], [Comparative Examples 1-2]
The composition of Example 1 was changed, and the others were similarly produced with resin-attached aluminum pigments and paints, and were evaluated for characteristics.
Table 1 shows the compositions and evaluation results of Examples 2 to 7 and Comparative Examples 1 and 2.
In addition, resin did not elute from the resin adhesion aluminum pigment of the comparative example 1, and the weight average molecular weight of dissolved solid content was not able to be measured.

[Comparative Example 3]
0.1 g of polyacrylic resin (manufactured by Toagosei Co., Ltd., UP-1000, molecular weight) relative to 2.7 g of commercially available aluminum paste (Asahi Kasei Chemicals Corporation, GX-4100 “average particle size 10 μm, non-volatile content 74%”) 3,000) was added and mixed for 10 minutes to obtain a resin blend aluminum pigment.
Furthermore, 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 were added, and the mixture was stirred with a magnetic stirrer for 10 minutes to obtain a metallic ink.
The obtained metallic ink was applied to a PET film with a bar coater so as to have a dry film thickness of 2 μm to obtain a coating film. The evaluation results are shown in Table 1 below.

  In Examples 1 to 6, it was possible to obtain excellent initial adhesion, metallic luster, design, and high concealment.

  The resin-attached aluminum pigment of the present invention is used for paints and printing inks for information home appliances represented by automobiles, general home appliances, and mobile phones, specifically, metals such as iron and magnesium alloys, or plastics. It has industrial applicability in paint and ink applications for such substrates.

Claims (3)

(A) an aluminum pigment;
(A) a resin compound attached to the aluminum pigment, (B) a radically polymerizable monomer and / or oligomer polymer having one or more double bonds in the molecule;
Including,
When the solid content after washing with chloroform was dispersed in dimethylformamide and stirred at 70 ° C. for 24 hours, the mass ratio (b) / (a) of (a) insoluble solid content and (b) dissolved solid content was 0. .0001-0.1,
(B) A resin-attached aluminum pigment having a PMMA-converted weight average molecular weight of 1,000 to 30,000, as measured by GPC, of the dissolved solid content.   The coating material containing the resin adhesion aluminum pigment of Claim 1.   An ink containing the resin-attached aluminum pigment according to claim 1.