JP6690319B2 - Chromatic fine particle capsule - Google Patents

Description

  The present invention relates to a chromatic color fine particle capsule that exhibits a clear chromatic color as a structural color.

  Structural color refers to the coloring phenomenon due to the fine structure of the wavelength of light or less, and in familiar examples, it is observed from compact discs, soap bubbles, morpho butterflies, and beetles.

  In recent years, development is underway to artificially create a regular periodic structure that emits a structural color. Among them, the structural color of colloidal crystals in which fine silica particles and fine polymer particles are regularly structured attracts attention because of the ease of fine particle synthesis.

  There are two known methods for regularly structuring fine particles: a method that uses self-assembly in the drying process of a fine particle dispersion and a method that uses repulsion between fine particles in a dispersion state. Has been. Although the method utilizing self-assembly in the drying process is simple, it has a drawback that it is difficult to control because the resulting structure depends on the drying conditions of the medium and the uniformity of fine particles. (Patent Document 1) In addition, a method utilizing repulsion between fine particles in a dispersion state controls the repulsion strength by controlling the concentration of the fine particles in a medium and the electrical conductivity of the dispersion liquid, whereby the fine particles are regularly dispersed. Although the arrangement can be achieved, it has a problem in practical use such as having to be used by injecting it into a fine cell because it has the fluidity of the dispersion liquid. (Patent Document 2, Non-Patent Document 1)

  In Patent Document 3, a droplet surface of an aqueous dispersion of resin fine particles having a multi-layered structure is coated with a UV curable monomer using a micro flow channel, and by curing this, a chromatic color fine particle dispersion capsule is obtained. It is reported that it can be obtained. However, this method has a problem in that productivity is poor because the UV monomer used may destroy the dispersed structure of the fine particles and it is necessary to use a micro flow channel.

  As described above, various methods for expressing chromatic colors by regularly structuring the fine particles have been studied, but problems remain in the difficulty of control, practicality, and productivity.

JP, 2009-229945, A JP, 2005-060653, A International publication number WO2013 / 082597

"Beautiful colloids and the world of interfaces" published by Matsuo, 2001

  An object of the present invention is to provide a chromatic color fine particle capsule that can be produced by a simple method.

That is, the present invention is a chromatic fine particle capsule comprising a wall material and inclusions,
The wall material is a reaction product of a water-soluble polyfunctional amine (c1) and a water-insoluble polyfunctional isocyanate,
The present invention relates to a chromatic color fine particle capsule, wherein the inclusion includes fine particles exhibiting a structural color.

  Further, the present invention relates to the chromatic fine particle capsule, wherein the water-soluble polyfunctional amine (c1) contains a bifunctional amine in an amount of 50% by weight or more based on the entire water-soluble polyfunctional amine (c1).

  The present invention also relates to the above chromatic fine particle capsule, wherein the water-insoluble polyfunctional isocyanate contains trifunctional or higher functional isocyanate in an amount of 50% by weight or more based on the whole water-insoluble polyfunctional isocyanate.

  Further, the present invention relates to the chromatic color fine particle capsule according to any one of claims 1 to 3, wherein the fine particles include acrylic polymer fine particles, and the acrylic polymer fine particles have an acid value of 10 to 70 mgKOH / g. .

  Further, the present invention relates to the above-mentioned chromatic fine particle capsule, characterized in that the inclusion contains a black achromatic substance inside and / or outside of the fine particles.

  The chromatic color fine particle capsule of the present invention can be produced by a simple method, and an excellent chromatic color can be obtained.

  The features of the chromatic color fine particle capsule of the present invention will be further described below.

<Chromatic fine particle capsule (A)>
In the chromatic fine particle capsule (A) of the present invention, the wall material (C) contains a resin obtained by addition polymerization reaction of a water-soluble polyfunctional amine (c1) and a water-insoluble polyfunctional isocyanate (c2) as monomer components. And includes fine particles (b1) forming a structure exhibiting a structural color. By including the fine particles (b1), the capsule can have a chromatic color. By using a resin, which is an addition polymerization reaction product of the water-soluble polyfunctional amine (c1) and the water-insoluble polyfunctional isocyanate (c2), as the wall material (C), it is possible to obtain fine particles forming a structure exhibiting a structural color. Capsule can be easily encapsulated while maintaining color development.

The chromatic color fine particle capsule (A) is not particularly limited, but the chromatic color fine particle capsule (A) can be easily prepared by using, for example, an interfacial polymerization method. When the medium of the chromatic fine particle dispersion (B) is water, first, the water-soluble polyfunctional amine (c1) is added to the chromatic fine particle dispersion, and further, the water-insoluble polyfunctional isocyanate is added to the capsule medium which is insoluble in water. When (c2) is added to the chromatic fine particle dispersion (B), the water-soluble polyfunctional amine (c1) and the water-insoluble polyfunctional isocyanate (c2) are polymerized to form a wall material (C), The chromatic fine particle dispersion capsule (A) can be obtained.
The chromatic color fine particle capsule (A) does not necessarily have to be the core-shell type. There may be one or more partitions inside the capsule and the dispersion within the capsule may not be integral.

<Chromatic color fine particle dispersion (B)>
The chromatic fine particle dispersion (B) of the present invention has fine particles (b1) and a medium (b2), and the fine particles (b1) have a regular structure in the medium (b2), whereby the chromatic color due to the structural color Is shown. In many cases, the chromatic color fine particle capsule (A) includes a dispersion composed of a large number of fine particles (b1) forming a structure exhibiting a structural color. However, the case where the capsule (A) contains one fine particle (b1) is not excluded. The capsule (A) has a structural color, but may not contain fine particles in a so-called dispersion state.

<Fine particles (b1)>
In the present invention, the fine particles (b1) are powders having an average particle diameter of 100 to 400 nm, which are not dissolved in the medium (b2) but exist in a dispersed state. When the average particle size of the fine particles (b1) is within the above range, a chromatic color in the visible region can be obtained.

  Since the chromatic color is obtained by the regular structure of the fine particles (b1), it is desirable that the particle diameter of the fine particles (b1) be as uniform as possible. In the present invention, the coefficient of variation Cv, which is an index of the variation in particle size of the fine particles (b1), is preferably 30% or less, more preferably 20% or less. When the variation coefficient Cv value is larger than 30%, the regularity of the structure of the fine particles (b1) cannot be sufficiently obtained, and the chromatic color may not be obtained.

  The average particle diameter in the present invention refers to the cumulative median diameter at which the cumulative curve is 50% when the cumulative curve is calculated with the total volume of the powder group as 100%, and the dynamic light scattering. It can be measured by the method.

  The average particle size can be measured by the dynamic light scattering method as follows. The fine particles (b1) are dispersed in water so that the weight becomes 500 to 2000 times. About 5 ml of the dispersion is injected into a cell of a measuring device [Microtrac (manufactured by Nikkiso Co., Ltd.)], and a solvent (water in the present invention) corresponding to the sample and a refractive index condition of the polymer are input, and then measurement is performed. The value of the cumulative median diameter obtained at this time is defined as the average particle diameter.

Further, in the present invention, the coefficient of variation Cv value representing the uniformity of particle diameter refers to a value defined by the following formula, and like the average particle diameter, can be measured by the dynamic light scattering method.

[Cv value] = ([standard deviation of particle size] / [average particle size])

  Examples of the fine particles (b1) include acrylic resin fine particles, polystyrene fine particles, polyester fine particles, polyolefin fine particles, polyether fine particles, nylon resin fine particles, melamine resin fine particles, silicone resin fine particles, polyamide fine particles, silica fine particles, titanium oxide fine particles, and the like. Copolymers and composites can be used.

  In the present invention, as the fine particles (b1), it is preferable to use acrylic resin fine particles having a (meth) acrylic acid-based monomer having a (meth) acrylic group in the molecule as a monomer component. By having an acrylic acid-based monomer as a monomer component, it is possible to obtain a chromatic color having excellent weather resistance, which is unlikely to undergo photo-degradation discoloration under irradiation of natural light such as sunlight or white light.

In the present invention, “(meth) acrylic” means at least one selected from “acrylic” and “methacrylic”, and “(meth) acrylic acid” is at least selected from “acrylic acid” and “methacrylate”. It means one kind.

Examples of the (meth) acrylic acid-based monomer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, (meth) Isobutyl acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, lauryl (meth) acrylate, nonyl (meth) acrylate, (meth ) Alkyl (meth) acrylates such as decyl acrylate and dodecyl (meth) acrylate,
Aromatic (meth) acrylic acid ester such as phenyl (meth) acrylate,
Substituted (meth) acrylic acid alkyl ester such as methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, propoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, ethoxypropyl (meth) acrylate;
(Meth) acrylic acid trifluoromethylmethyl, (meth) acrylic acid-2-trifluoromethylethyl, (meth) acrylic acid-2-perfluoromethylethyl, (meth) acrylic acid-2-perfluoroethyl-2- Perfluorobutylethyl, (meth) acrylic acid-2-perfluoroethyl, (meth) acrylic acid perfluoromethyl, (meth) acrylic acid dipa-fluoromethylmethyl, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoro Partial or complete fluorine-substituted monomers of ethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole (meth) acrylic acid;
Dialkylaminoalkyl (meth) acrylates such as diethylaminoethyl (meth) acrylate;
Ethylene glycol di (meth) acrylic acid ester, diethyl glycol di (meth) acrylic acid ester, triethylene glycol di (meth) acrylic acid ester, polyethylene glycol di (meth) acrylic acid ester, dipropylene glycol di (meth) acrylic acid Examples thereof include esters and (meth) acrylic acid ester monomers such as (poly) alkylene glycol di (meth) acrylic acid esters such as tripropylene glycol di (meth) acrylic acid ester.
In addition, (meth) acrylic acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, norbornene dicarboxylic acid, bicyclo [2.2.1] hept-2-ene-5,6-dicarboxylic acid, etc. (Meth) acrylic acid-based monomer having a carboxylic acid group, maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo [2.2.1] hept-2-ene-5,6-dicarboxylic acid Monomers having carboxylic acid anhydride groups such as acid anhydrides, monomers having amide groups such as (meth) acrylamide, N-methylol (meth) acrylamide, diacetone acrylamide, and 1,1,1-trihydroxymethylethanetri (Meth) acrylate, 1,1,1-trishydroxymethylmethylethanetri (meth) Acrylate, 1,1,1-trishydroxymethylpropane tri (meth) acrylate, hydroxy vinyl ether, hydroxypropyl vinyl ether, hydroxybutyl vinyl ether,
A (meth) acrylic monomer having a functional group such as a monomer having a hydroxyl group such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, diethylene glycol mono (meth) acrylate, and glycidyl (meth) acrylate is used. Can be mentioned.

  In the present invention, the acrylic polymer fine particles preferably have an acid value of 10 to 70 mgKOH / g, from the viewpoints of stability of ordered structure during encapsulation, stability during polymerization, and induction of ordered structure of fine particles. More preferably, it is ˜50 mg KOH / g. When the acid value is larger than 70 mgKOH / g, a copolymer of a water-soluble polyfunctional amine (c1) and a water-insoluble polyfunctional isocyanate (c2) used as a wall material (C) or a water-soluble polyfunctional monomer which is a monomer thereof Due to the interaction with the amine (c1), a stable capsule structure may not be obtained.

The acid value can be measured by titration as follows. About 1 g of fine particles was precisely weighed in a ground-in stopper Erlenmeyer flask, 100 ml of a mixed solution adjusted to have a volume of toluene / ethanol = 2/1 was added, and well stirred. To this, a phenolphthalein reagent solution was added as an indicator, held for 30 seconds, and then titrated with a 0.1N alcoholic potassium hydroxide solution until the solution became a bright red color. The acid value (unit: mgKOH / g) was calculated by the following formula as the value of the fine particles in a dry state.
Acid value (mgKOH / g) = {(5.611 × a × F) / S} / (nonvolatile component concentration / 100)
However, S: sampling amount (g)
a: Consumption of 0.1N alcoholic potassium hydroxide solution (ml)
F: titer of 0.1N alcoholic potassium hydroxide solution

  In the present invention, from the viewpoint of adjusting the refractive index of the acrylic resin fine particles, it is preferable to have 10.0% by weight or more of monomers having a refractive index of 1.50 or more as all monomer components, and 10.0% by weight or more and 80% by weight or more. % Or less is more preferable. In the present invention, as the refractive index of the monomer, the value described in POLYMER HANDBOOK FOURTH EDITION (J. Brandrup, E. H. Immergut, E. A. Grulke) was used.

  Examples of the monomer having a refractive index of 1.50 or more include styrene, methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, diethylstyrene, triethylstyrene, propylstyrene, butylstyrene, hexylstyrene, heptylstyrene, octylstyrene, and methoxy. Styrene, fluorostyrene, chlorostyrene, dichlorostyrene, chloromethylstyrene, bromostyrene, dibromostyrene, benzyl (meth) acrylate, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate , Phenoxy polyethylene glycol (meth) acrylate, pentabromophenyl (meth) acrylate, pentabromobenzyl (meth) acrylate, divinylben Emissions, and the like.

<Medium (b2)>
In the present invention, the medium (b2) means a liquid substance in which the fine particles (b1) are dispersed. Examples thereof include polar solvents such as water, methanol, ethanol, and isopropanol, and nonpolar solvents such as ethyl acetate, methyl ethyl ketone, acetone, toluene, and normal hexane.

<Black achromatic object (b3)>
In the present invention, the black achromatic substance (b3) refers to a substance having no tint and low lightness, and is used for making the color development due to the regular structure of the fine particles (b1) clearer. The brightness of the black achromatic substance (b3) is preferably 5 or less, and more preferably 3 or less. The black achromatic substance (b3) is not particularly limited, but examples thereof include carbon black (acetylene black, Ketjen black, furnace black), oil smoke, graphite, black dyes (nigrosine, azine, etc.), squid ink, India ink, etc. Is mentioned.

  In the present invention, the black achromatic substance (b3) is preferably contained in an amount of 0.001% by weight or more based on the fine particles (b1). If the amount is less than 0.001% by weight, the effect of the black achromatic substance (b3) becomes insufficient, and a clear chromatic color may not be obtained. The black achromatic substance (b3) is preferably contained in the fine particles (b1) in an amount of 0.001% by weight or more and 10% by weight or less. If the black achromatic substance is contained in an amount of more than 10% by weight with respect to the fine particles, interference light due to the structure of the fine particles is also absorbed, and sufficient color development may not be obtained.

<Other (b4)>
In addition to the above-mentioned fine particles (b1), medium (b2) and black achromatic substance (b3), the chromatic color fine particle dispersion (B) of the present invention may optionally contain, for example, a lubricant or an ultraviolet ray absorbent. Additives such as agents, antioxidants, antistatic agents, charge imparting agents, surfactants, dispersion stabilizers, defoamers and stabilizers may also be added.

<Wall material (C)>
The wall material (C) of the chromatic fine particle dispersion capsule (A) is preferably a resin containing 80% or more by weight of a water-soluble polyfunctional amine (c1) and a water-insoluble polyfunctional isocyanate (c2) as monomer components. By using such a resin, a capsule can be obtained while maintaining the regular structure of the chromatic fine particle dispersion (B) in the capsule.

  In the present invention, the term “water-soluble” means that when it is added to ion-exchanged water at 25 ° C. in a proportion of 1% by weight and well stirred, it is completely dissolved. The term “water-insoluble” refers to water-insoluble water that is added to ion-exchanged water at 25 ° C. in a proportion of 1% by weight and, when stirred well, is separated from water and is not completely dissolved.

<Water-soluble polyfunctional amine (c1)>
In the present invention, the water-soluble polyfunctional amine (c1) refers to a water-soluble compound having two or more primary and secondary amino groups in the molecule. In the present invention, 80% by weight or more of the water-soluble polyfunctional amine (c1) is preferably a water-soluble bifunctional amine. When the content of the trifunctional or higher functional water-soluble polyfunctional amine is 20% by weight or more, the regular structure of the chromatic color fine particle dispersion (B) is disturbed, and it becomes impossible to obtain a capsule in which the chromatic color is maintained. There is a nature.

  Examples of the water-soluble bifunctional amine include ethylenediamine, trimethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, 2,2-dimethyl-1,3-propanediamine, hexamethylenediamine, octamethylenediamine, piperazine, and N. -Methylethylenediamine, N-ethylethylenediamine, N-methyl-1,3-propanediamine, N, 2-methyl-1,3-propanediamine, N-isopropylethylenediamine, N-isopropyl-1,3-diaminopropane, N , N'-dimethylethylenediamine, N, N'-diethylethylenediamine, phenylenediamine, tolylenediamine, xylylenediamine, isophoronediamine, diaminocyclohexane and the like. Further, two or more of the above-mentioned substances can be used in combination.

  Examples of the water-soluble polyfunctional amine (c1) other than the water-soluble bifunctional amine include diethylenetriamine, triethylenetetramine, tetraethylenepentamine and the like. Further, two or more of the above-mentioned substances can be used in combination.

<Water-insoluble polyfunctional isocyanate (c2)>
In the present invention, the water-insoluble polyfunctional isocyanate (c2) means a water-insoluble compound having two or more isocyanate groups in the molecule. In the present invention, 50% or more of the water-insoluble polyfunctional isocyanate (c2) is preferably a tri- or more functional water-insoluble polyfunctional isocyanate. When the content of tri- or higher functional water-soluble polyfunctional amine is less than 50%, the cross-linking structure of the wall material becomes fragile and a capsule structure may not be obtained.

  Examples of the tri- or more functional water-insoluble polyfunctional isocyanate include toluren diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, bis (isocyanatomethyl) cyclohexane, and nurate of difunctional isocyanate such as m-xylylene diisocyanate. , Trimethylolpropane adduct, biuret and the like. Further, as the water-insoluble polyfunctional isocyanate, a prepolymerized compound can also be used. Further, two or more of the above-mentioned substances can be used in combination.

  Examples of the water-insoluble bifunctional isocyanate include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, bis (isocyanatomethyl) cyclohexane, m-xylylene diisocyanate, and the like. Further, two or more of the above-mentioned substances can be used in combination.

  A compound (c3) copolymerizable with the water-soluble polyfunctional amine (c1) and the water-insoluble polyfunctional isocyanate (c2) can be used together as a monomer component for the wall material of the chromatic color fine particle dispersion capsule.

  Examples of the compound (c3) copolymerizable with the water-soluble polyfunctional amine (c1) and the water-insoluble polyfunctional isocyanate (c2) include ethylene glycol, 1,4-butanediol, neopentyl glycol and butylethylpentanediol. , Polyglycerin, trimethylolpropane, pentaerythritol, and other polyfunctional alcohols, polyester polyols, polyether polyols, polyurethane polyols that are reaction products of polyester polyols and / or polyether polyols and diisocyanates, polyether adducts of polyhydric alcohols, etc. Examples thereof include polyfunctional alcohol polymers.

  From the above, by using a resin having a water-soluble polyfunctional amine (c1) and a water-insoluble polyfunctional isocyanate as a monomer component as a wall material and including a chromatic color fine particle dispersion, an excellent chromatic color can be easily obtained. It can be seen that colored fine particle dispersion capsules are obtained. The chromatic color fine particle dispersion capsule of the present invention can be used like an ordinary pigment or an effect pigment, and can be used as a paint, an ink jet ink, a color filter, a coloring masterbatch, or a coloring material for a sensor.

  Hereinafter, the present invention will be described by way of examples, but the present invention is not limited to the following examples. In the description, "parts" means "parts by weight" and "%" means "% by weight" unless otherwise specified.

<S-1: Preparation of chromatic fine particle dispersion (B)>
A 2-liter four-necked flask was charged with 300 parts by weight of pure water and 2.0 parts by weight of ADEKA REASOAP SR-10 as an emulsifier, and heated to 80 ° C. with stirring. Next, 1.2 parts by weight of potassium persulfate was added as an initiator, and a mixed solution of 6 parts of acrylic acid as a monomer, 89 parts by weight of styrene, 60 parts by weight of methyl methacrylate, and 45 parts by weight of butyl acrylate was added dropwise over 100 minutes. did. After the dropping was completed, the temperature was maintained at 80 ° C. with stirring for 2 hours. The fine particle dispersion obtained by this emulsion polymerization contained fine particles (b-1) and had an average particle diameter of 205 nm. Subsequently, Ketjen Black (Lion Co., Ltd./Lion paste W-310A) as a black achromatic substance was added to this fine particle dispersion in an amount of 0.1% by weight based on the fine particles to obtain the desired chromatic color. A fine particle dispersion (S-1) was obtained.

<S-2 to 5: Preparation of chromatic fine particle dispersion (B)>
300 parts by weight of pure water and ADEKA REASOAP SR-10 as an emulsifier were added to a 2-liter four-necked flask in accordance with Table 1 and heated to 80 ° C. with stirring. Next, 1.2 parts by weight of potassium persulfate was added as an initiator, and a mixed solution containing monomers in various proportions according to Table 1 was added dropwise over 100 minutes. After the dropping was completed, the temperature was maintained at 80 ° C. with stirring for 2 hours. The fine particle dispersion obtained by this emulsion polymerization contained fine particles (b-1), and the average particle diameter thereof was 100 nm to 600 nm. Subsequently, Ketjen Black (Lion Co., Ltd./Lion paste W-310A) as a black achromatic substance was added to this fine particle dispersion according to Table 1 to obtain a desired chromatic color fine particle dispersion (S-2 to 5). Got

<S-6: Preparation of chromatic fine particle dispersion (B)>
Ketjenblack (Lion paste / Lion paste W-310A) as a black achromatic substance was added to the silica fine particle dispersion (MP-2040, Nissan Chemical Co., Ltd.) according to Table 1 to obtain the desired chromatic color fine particle dispersion ( S-6) was obtained.

Table 1 shows the monomer composition and properties of the above-mentioned acrylic polymer particles (A).

AA: Acrylic acid (refractive index 1.4202)
MAA: methacrylic acid (refractive index 1.432)
St: Styrene (refractive index 1.5470)
BzMA: benzyl methacrylate (refractive index 1.5120)
MMA: Methyl methacrylate (refractive index 1.4140)
BA: Butyl acrylate (refractive index 1.4180)
2EHA: Acrylic acid-2 ethylhexyl (refractive index 1.4360)
As the above-mentioned refractive index, the value described in POLYMER HANDBOOK FOURTH EDITION (J. Brandrup, EH Immergut, EA Grulke) was used.

<Example 1: Preparation of chromatic fine particle dispersion capsule (A)>
5 parts by weight of isophoronediamine was added to 95 parts by weight of the chromatic fine particle dispersion (S-1), and the mixture was well stirred. To 950 parts by weight of toluene and 50 parts by weight of hexamethylene diisocyanate biuret were added, this was slowly added drop by drop using a syringe. After completion of the dropping, the mixture was kept at room temperature for 6 hours while being slowly stirred. This was filtered through a mesh to obtain the target chromatic color fine particle dispersion capsule (A).

<Examples 2-11, Comparative Examples 1-2>
To 95 parts by weight of the chromatic fine particle dispersion (S-1 to 6), 5 parts by weight of the water-soluble polyfunctional amine and / or the water-soluble polyol shown in Table 2 were added and well stirred. To 950 parts by weight of toluene, 50 parts by weight of the non-water-soluble polyfunctional isocyanate shown in Table 2 was added at a rate shown in Table 2, and this was slowly added dropwise drop by drop using a syringe. After completion of the dropping, the mixture was kept at room temperature for 6 hours while being slowly stirred. This was filtered through a mesh to obtain the target chromatic color fine particle dispersion capsule (A). At this time, the chromatic color fine particle dispersion capsules (A) of Comparative Examples 1 and 2 could not be taken out because the capsules were broken and the chromatic color fine particle dispersion (B) flowed out. Further, in the chromatic fine particle dispersion capsule (A) of Example 7, a part of the capsule was ruptured.

Table 2 shows the monomers used for the above wall material preparation.

Table 2

<Color development evaluation test of chromatic fine particle dispersion (B)>
The color development of the chromatic fine particle dispersions (B) of S1 to 6 prepared above was evaluated from the reflection spectrum. 6.0 ml of each adjusted dispersion was added to a quartz cell (S20 curved bottom standard cell / manufactured by GL Sciences Inc.), and this reflection spectrum was measured with a spectrophotometer (Hitachi spectrophotometer / U-4100 manufactured by Hitachi High Technologies). Was measured using. The reflectance at each wavelength was calculated assuming that a circular plate having a diameter of 30 mm and a white disc of aluminum oxide having a thickness of 20 mm on the inner surface of the sphere on which the detector is installed is 100%. In the evaluation result, when the difference between the maximum reflectance of the structural color and the reflectance of the baseline not depending on the structural color is defined as the contrast of reflectance, when the contrast is 30% or more, ⊚, 20% or more and When it is less than 30%, it is evaluated as ◯, when it is 10% or more and less than 20%, it is evaluated as ◯ Δ, when it is 5% or more and less than 10%, it is evaluated as Δ, and when it is less than 5%.

<Coloring evaluation test of chromatic fine particle dispersion capsule (A)>
The color development of the chromatic color fine particle dispersion capsules (A) of Examples 1 to 11 prepared above was visually evaluated. The case where the color development of the chromatic color fine particle dispersion (B) before the capsule was maintained was evaluated as ◯, the case where the color development was decreased was evaluated as Δ, and the case where the color development was lost was evaluated as x.

  Table 3 shows the color development evaluation test results of the above-mentioned Examples and Comparative Examples.

Table 3

  From the results of Examples 1 to 11 in Table 3, it can be seen that the resin having the water-soluble polyfunctional amine (c1) and the water-insoluble polyfunctional isocyanate as the monomer component is used as the wall material and the chromatic fine particle dispersion is included. It was found that the chromatic color fine particle dispersion capsule can be stably produced and exhibits chromatic color.

  On the other hand, in Comparative Examples 1 and 2 which did not have a water-soluble polyfunctional amine as a monomer component, stable chromatic color fine particle dispersions could not be prepared. It is considered that this is because the wall material did not have sufficient strength because it did not have a water-soluble polyfunctional amine.

Among the water-soluble polyfunctional amines, Examples 1 to 5 using a wall material having 50% or more by weight of a bifunctional amine as a monomer have 50% or more by weight of a trifunctional or more polyfunctional amine as a monomer. Good color development was obtained as compared to Example 6 using the wall tax. This is because a wall material having 50% or more by weight of a bifunctional amine as a monomer was used, and thus, a chromatic color-maintained capsule is obtained without disturbing the regular structure of the chromatic color fine particle dispersion (B). It is believed that this was possible.
Among the water-insoluble polyfunctional isocyanates, Examples 1 to 5 in which wall materials having 50% or more by weight of trifunctional or more polyfunctional isocyanate as a monomer are used, 50% or more by weight of bifunctional isocyanate as a monomer. Good capsules were obtained as compared to Example 7, which used the wall tax. It is considered that this is because the wall material having 50% or more by weight of trifunctional or higher polyfunctional isocyanate as a monomer was used, and thus the wall material had a strong cross-linked structure.
In Examples 1 to 5 in which the acrylic polymer particles having an acid value of 10 to 70 mgKOH / g were used as the particles, good color formation was obtained as compared with Examples 8 to 10 in which the acrylic polymer particles were not used. Since the acrylic polymer fine particles having an acid value of 10 to 70 mgKOH / g were used, the induction of the ordered structure of the fine particles was appropriately obtained, and the acrylic polymer fine particles were not mixed with the water-soluble polyfunctional amine (c1) used as the wall material (C). It is considered that the structure could be maintained because the interaction with the copolymer of the water-soluble polyfunctional isocyanate (c2) and the water-soluble polyfunctional amine (c1) as the monomer thereof was small.

  The chromatic color fine particle dispersion capsule of the present invention can be used like ordinary pigments and effect pigments, and can be used as paints, ink jet inks, color filters, coloring masterbatches, and color materials for sensors.

Claims (5)

And wall material, comprising a inclusions, a chromatic microparticles capsule,
The wall material is Ri Na contain a water soluble polyfunctional amine and (c1) a water-insoluble polyfunctional isocyanate and a monomer component polymer,
A chromatic color fine particle capsule, wherein the inclusions include fine particles exhibiting a structural color.   The chromatic fine particle capsule according to claim 1, wherein the water-soluble polyfunctional amine (c1) contains a bifunctional amine in an amount of 50% by weight or more based on the total amount of the water-soluble polyfunctional amine (c1).   The chromatic fine particle capsule according to claim 1 or 2, wherein the water-insoluble polyfunctional isocyanate contains trifunctional or higher functional isocyanate in an amount of 50% by weight or more based on the whole water-insoluble polyfunctional isocyanate.   4. The chromatic fine particle capsule according to claim 1, wherein the fine particles include acrylic polymer particles, and the acid value of the acrylic polymer particles is 10 to 70 mgKOH / g. Further, the inclusion contains a black achromatic substance inside and / or outside of the fine particles, and the chromatic fine particle capsule according to claim 4.