JP2002053814A - Enamel particle dispersion, method for producing the same and multi-colored pattern coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an enamel particle dispersion, not precipitating during its storage even in using the large diameter of the dispersed particles for a large, smooth multi-colored pattern film, not aggregating the particles each other, forming a smooth film the cause of excellent storage stability, not deteriorating its designing property even applying the coating after a long time storage, and to provide a multi-colored pattern coating composition. SOLUTION: This enamel particle dispersion is characterized by dispersing the enamel composition (I) containing (A) a synthetic resin, (B) a coloring material and (C) a solvent in an aqueous dispersing medium (II) of pH 6-11, containing 0.01-5 wt.% polyvinyl alcohol and boric acid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an enamel particle dispersion and a method for producing the same. Further, the present invention relates to a multi-color paint composition containing two or more of the enamel particle dispersions.

[0002]

2. Description of the Related Art Conventionally, there are various types of coating compositions for forming a colorful coating film on the wall of a building. Among such paint compositions, paints that form a multi-colored paint film by one application are called multi-color paints, and are JIS K
5667-1983. According to this rule, the multi-color paint has a structure in which particles of two or more colors in a liquid or gel state are dispersed.

[0003] The idea about the composition of such a paint is as follows.
P. Beginning with the BUSCH patent, C. According to ZOLA, US Patent No. 2,591,904, Japanese Patent No. 231
No. 698, represented by an oil-in-water type colorful paint. After that, various varnished paints have been developed by paint technicians in Japan and overseas, all of which fall into the following categories.

1) Oil-in-water type (hereinafter referred to as O / W type) A dispersed phase, which is a colored organic solvent-based paint, is dispersed as a discontinuous phase in a water-soluble dispersion medium to a discernible size. Type. 2) Water-in-oil type (hereinafter referred to as W / O type) A type in which a dispersion medium is oily and an aqueous dispersion phase colored with the dispersion medium is dispersed as a discontinuous phase. 3) Oil-in-oil type (hereinafter referred to as O / O type) A type in which an oil-based dispersion medium is used, and an organic solvent-based enamel is used to disperse a colored sol-like substance that is incompatible with the dispersion medium in a discontinuous phase. . 4) Water-in-water type (hereinafter referred to as W / W type) A type in which an aqueous colored gel-like substance is dispersed in a discontinuous phase in an aqueous dispersion medium.

[0005] The above-mentioned various colorful pattern paints are prepared by dispersing a disperse phase in a dispersion medium and preventing them from mixing.
Use hydrophobicity like W type and W / O type,
Even in the case of the O / O type or the W / W type, mutually incompatible resins are used or the surface of the dispersed particles is gelled.

[0006] However, these various colorful paints have the problem that, in the storage state, the dispersed particles of each color settle or the dispersed particles coalesce. But a dispersant is used or a specific gelled film is formed, but none of them is sufficient. Therefore, when coating is performed after long-term storage, the gelling film has a large difference in the colorful pattern design feeling, that is, the degree of pattern spread and unevenness (smoothness) depending on the strength of the film. In some cases, it was not possible to stably express a desired colorful pattern design.

In the production of multicolor paints, a method of dispersing a dispersed phase in a dispersion medium with stirring is usually performed. However, if the strength of the dispersed particles is weak, the dispersed particles are broken by such stirring. As a result, not only cannot the dispersed particles having the target particle size be produced, but also the entire dispersed phase may be united into one mass.

Further, the multicolor paint has a mechanism in which the dispersed particles are fused together to form a continuous film in the film forming process. Therefore, if a stronger film is formed on the surface of the dispersed particles in order to improve the storage stability of the multicolor paint, the coating film formed from such a multicolor paint will hinder the fusion of the dispersed particles. The resulting film was a relatively coarse, discontinuous film in a porous state, and had uncertainties in the weather resistance and antifouling properties of the coating film.

[0009] In particular, recently, as a design of a building exterior coating film formed from these multicolored paints, each color portion has a large pattern as seen in the design of a natural stone, and a multicolored pattern is formed even at a short distance. Things that are clearly recognized are being favored. Therefore, in order to form such a large pattern, the grains must be large. However,
When the particle size of the dispersed particles is increased, the dispersed particles settle during storage, and the particles are likely to unite. Also, in order to prevent this, a method of crosslinking the dispersed particles to form strong crosslinked particles has been performed.However, when a multi-colored pattern paint using such particles is applied, it is formed as described above. The coated film is poor in the state of crushing and fusion of the particles, and the smoothness of the formed multi-colored coating film is insufficient or a discontinuous film in a porous state is formed, and the weather resistance and antifouling property are It will be inferior.

[0010] In addition, when attention is paid to the cross-linking form of the multicolored paint, it is roughly classified into those in which the inside of the dispersed particles are cross-linked (type 1) and those in which the surface of the dispersed particles is cross-linked (type 2).

Of these, the dispersed particles of type 1 contain a resin component inside the particles for the purpose of improving the weather resistance of the particles themselves.
The resin component is reacted with a crosslinkable component.
However, in the case of the type 1 dispersed particles, the degree of crushing at the time of coating is reduced, so that a gap may be generated between the particles in the formed coating film. Such a coating film becomes a discontinuous film in a porous state, which causes a problem in terms of design. In particular, recently, as a design of a coating film formed from these colorful paints, each color portion is a large pattern as seen in the design of natural stone, and a colorful pattern is clearly recognized even at a short distance. However, it is difficult to obtain such a design with dispersed particles of type 1. In addition, the discontinuous film formed by type 1 does not have a sufficient protective function of the underlayer, and has a portion that is uneasy in weather resistance.

On the other hand, in the type 2 dispersed particles, the type 1
Particles are easily crushed and gaps between particles are less likely to occur. However, at the time of spray coating, due to fluctuations in conditions such as the air pressure of the coating equipment to be used and the tip diameter of the gun tip, partitions on the surface of the dispersed particles are easily broken, and the contents may be scattered and scattered. . The coating film thus formed has a string-like pattern, and it is difficult to obtain a colorful pattern with high aesthetics. Therefore, such a multi-color paint must be applied under very limited coating conditions, and the degree of freedom in selecting coating equipment is low.

In addition, recently, these colorful paints are used in a wide variety of applications, and the design of coating films to be formed is diversified as required for each application. In particular, there is an increasing demand for a relatively colorful and unclear pattern on the wall of a building, which is a modest pattern that does not make the wall conscious, yet creates a deep and luxurious atmosphere.

However, in a multi-color paint, the liquid or gel-like dispersed particles of two or more colors in the composition are crushed to form a pattern, so that a large difference in hue between the dispersed particles appears and the contrast becomes stronger. Therefore, it is difficult to form such a modest and deep pattern.

[0015]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and a first problem to be solved by the present invention is to provide a large and smooth multi-colored coating film when coated. To form, even if the particle diameter of the dispersed particles is increased,
Enamel particles that do not settle during storage, do not coalesce with each other, have excellent storage stability, do not lose their design even after long-term storage, and form a smooth coating film. An object of the present invention is to provide a dispersion and a multi-color pattern coating composition.

The second problem to be solved by the present invention together with the first problem is that in coating, the pattern formed is hardly changed even by various conditions when the coating equipment is changed, and each color is not changed. A highly weather-resistant enamel particle dispersion and a multi-color paint composition that can obtain a finish in which the pattern of the pattern is large and formed in a substantially circular shape, has a high degree of freedom in selection of coating equipment, and can sufficiently exhibit a base protection function The purpose is to provide.

Further, the present invention produces a multicolor paint composition in which the hue difference between the dispersed particles is not so clear, the hue changes continuously and subtly, and a conservative and deep multicolor design can be obtained. An object of the present invention is to provide an enamel particle dispersion that can be used.

[0018]

Means for Solving the Problems In order to solve the above problems, the present inventors have conducted intensive studies and as a result, have found that the above objects can be achieved by using the enamel particle dispersion shown below. It was completed. That is,
The present invention is the following enamel particle dispersion, its production method,
Further, the present invention relates to a multi-color paint composition.

1. The enamel composition (I) containing the synthetic resin (A), the coloring material (B) and the solvent (C) contains polyvinyl alcohol at a concentration of 0.01 to 5% by weight, and has a pH of boric acid. 6-11 aqueous dispersion medium (II)
An enamel particle dispersion characterized by being dispersed in a liquid.

2. Polyvinyl alcohol has a weight average molecular weight of 10,000 to 100,000 and a saponification degree of 80 to 100
2. The enamel particle dispersion according to the above 1, wherein

3. 3. The enamel particle dispersion according to the above item 2, wherein the polyvinyl alcohol is a cationic polyvinyl alcohol.

4. 4. The enamel particle dispersion according to any one of the above items 1 to 3, wherein the synthetic resin (A) is a vinyl-based synthetic resin having an acid value of 0 to 30.

5. The enamel composition (I) is based on 100 parts by weight of the solid content of the synthetic resin (A) and the coloring material (B)
The enamel particle dispersion according to any one of the above items 1 to 4, comprising 10 to 100 parts by weight and 100 to 1000 parts by weight of the solvent (C).

6. The enamel composition (I) contains a viscosity modifier (D), and at a temperature of 20 ° C., the viscosity at 20 rpm (guideline value at the fourth rotation) measured by a BH type viscometer is 0.2 to 15 Pa -The enamel particle dispersion according to any one of the above 1 to 5, wherein s is adjusted so that the TI value determined as follows is in the range of 1.0 to 8.0. <TI value> TI value: a value obtained by using a BH-type viscometer according to Equation 1. TI value = η1 / η2 (Equation 1) (However, apparent viscosity at η1: 2 rpm (Pa ·
s: pointer value at the second rotation), η2: apparent viscosity at 20 rpm (Pa · s: pointer value at the fourth rotation)).

[7] The viscosity modifier (D) is replaced with a synthetic resin (A)
7. The enamel particle dispersion according to the above item 6, wherein 1 to 10 parts by weight of the solid content is contained.

8. The maximum particle diameter of the enamel particles is 1 to 1
The enamel particle dispersion according to any one of the above 1 to 7, which is 0 mm.

9. Any one of the above items 1 to 8, wherein the aqueous dispersion medium (II) forms a coating film having a opacity of 0.05 to 0.60 in JIS K 5660 “Shiny synthetic resin emulsion paint” 4.8 An enamel particle dispersion according to any one of the above.

10. Boric acid is added to the aqueous solution of polyvinyl alcohol having a concentration of 0.01 to 5% by weight while or after the enamel composition (I) is dispersed, and the pH is adjusted to 6 to 11 before or after the addition of boric acid. 10. The method for producing an enamel particle dispersion according to any one of the above items 1 to 9, wherein the enamel particle dispersion is adjusted.

(11) A multicolor paint composition comprising two or more of the enamel particle dispersions according to any one of the above 1 to 9.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail along with its embodiments. Enamel composition (I) of the present invention
Contains a synthetic resin (A), a coloring material (B) and a solvent (C), and further contains various additives as necessary. The enamel composition (I) is dispersed in the form of particles in the aqueous dispersion medium (II).

[Synthetic resin (A)] Enamel composition (I)
As the synthetic resin (A) to be used for the above, a binder used for an existing paint can be used without particular limitation as long as it can form an enamel by mixing with the coloring material (B) and the solvent (C). . For example, acrylic, acrylic silicon, epoxy, urethane, alkyd,
Examples thereof include silicone-based and fluorine-based solvent-soluble types and solvent-dispersed types (including emulsion types).

As the synthetic resin (A), a crosslinkable functional group-containing copolymer containing a functional group which is crosslinked by a curing agent or a curing catalyst can be used. Examples of the crosslinkable functional group of such a crosslinkable functional group-containing copolymer include a hydroxyl group, an isocyanate group, an epoxy group, an amino group, an alkoxysilyl group, a carbonyl group, and a carboxyl group.

The synthetic resin (A) has an acid value of 0 to 0.
It is preferable to use 30 vinyl synthetic resins. Examples of the monomer constituting the vinyl synthetic resin include, for example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, and the like. Acrylic esters and methacrylic esters, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, hydroxyl-containing vinyl compounds such as 2-hydroxyvinyl ether, acrylic acid, methacrylic acid,
Carboxylic acids such as itaconic acid and fumaric acid, and acid anhydrides such as maleic anhydride; epoxy compounds such as glycidyl acrylate and glycidyl methacrylate; amino compounds such as diethylaminoethyl acrylate, diethylaminoethyl methacrylate and aminoethyl vinyl ether; acrylamide and methacryl Amide, itaconic amide, α-ethylacrylamide, crotonamide,
Amide compounds such as fumaric diamide, maleic diamide, N-butoxymethylacrylamide, N-butoxymethylacrylamide, N-butoxymethylmethacrylamide, acrylonitrile, styrene, α-methylstyrene, vinyl chloride, vinyl acetate, vinyl propionate, etc. And vinyl-based synthetic resins are one or more of these.
Obtained by polymerizing more than one species.

[0034] Among the above-mentioned vinyl-based synthetic resins, acrylic silicone resin is preferably used from the viewpoint of weather resistance when a multi-colored pattern film is formed. As the acrylic silicone resin, for example, the following formula 1,

Embedded image (In the formula, X is a hydrolyzable group, R ¹ and R ² are hydrogen or an alkyl group, an aryl group or an aralkyl group having 1 to 10 carbon atoms, and n is an integer of 1 to 3.)
A vinyl resin containing at least one hydrolyzable silyl group in the molecule as shown by
The weight average molecular weight is about 10,000 to 200,000.

Such a vinyl resin is represented by the following formula 2,

Embedded image (Wherein, R ³ is a monovalent hydrocarbon group selected from an alkyl group having 1 to 10 carbon atoms, an aryl group, and an aralkyl group; X is a halogen, alkoxy, acyloxy, aminoxy, phenoxy, thioalkoxy, amino group A group selected, n is an integer from 1 to 3), a method of causing a hydrosilylation reaction of a hydrosilane compound and a vinyl polymer having a carbon-carbon double bond with a catalyst,

Embedded image (Wherein, R ⁴ is a monovalent hydrocarbon group selected from an alkyl group, an aryl group, and an aralkyl group having 1 to 10 carbon atoms, R ⁵ is an organic residue having a polymerizable double bond, X is a halogen, A group selected from alkoxy, acyloxy, aminoxy, phenoxy, thioalkoxy and amino, n is 1
Is an integer from 1 to 3. ) And various vinyl compounds described above by radical polymerization.

The acid value of the vinyl-based synthetic resin is not particularly limited, but is preferably from 0 to 30. Even when the acid value is 0, coalescence of the enamel particles can be avoided by the protective colloid effect of the polyvinyl alcohol adsorbed on the surface of the enamel particles. On the other hand, when the acid value is larger than 30, it tends to be difficult to form particles when the enamel composition (I) is mixed with the aqueous solution containing polyvinyl alcohol.

[Coloring material (B)] As the coloring material (B), those generally used in paints can be used. For example, titanium oxide, zinc oxide, calcium carbonate,
Alumina, silica, kaolin, carbon black, lamp black, bone black, graphite, iron black, copper chrome black, cobalt black, copper manganese iron black, red iron, molybdate orange, permanent red,
Permanent carmine, anthraquinone red, perylene red, quinacridone red, yellow iron oxide, titanium yellow, first yellow, benzimidazolone yellow, chrome green, cobalt green, phthalocyanine green, ultramarine, navy blue, cobalt blue, phthalocyanine blue, quinacridone violet, di Oxazine violet and the like.

[Solvent (C)] Examples of the solvent (C) include petroleum benzene, n-heptane, n-hexane, mineral spirits, aliphatic hydrocarbons such as terpene and kerosene, and aromatics such as benzene, toluene and xylene. Hydrocarbons, alicyclic hydrocarbons such as cyclohexane, dichloroethane,
Chlorinated hydrocarbons such as trichlene, perchrene, ether alcohols such as methyl cellosolve, cellosolve solvent, butyl cellosolve, isobutyl cellosolve,
Alcohols such as methyl alcohol, ethyl alcohol, n-propanol, iso-propanol, n-butanol, esters such as methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, isobutyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone ,
Ketones such as cyclohexanone and optionally water can also be used.

[Viscosity Control Agent (D)] The enamel composition (I) contains a synthetic resin (A), a coloring material (B) and a solvent (C). In addition, it is preferable to adjust the viscosity to the specific viscosity described below. Examples of the viscosity modifier (D) include inorganic materials such as bentonite, sericite, ultrafine silica, surface-treated calcium carbonate, amide wax, hydrogenated castor oil wax, benridene sorbitol, metal soap, polyethylene oxide, and sulfate ester. Organic compounds such as anionic activators can be used.

The viscosity of the enamel composition (I) adjusted by adding the viscosity adjusting agent (D) is defined as a value at 20 ° C. of a viscosity at 20 rpm (a guide value at the fourth rotation) measured with a BH type viscometer of 0. 0.2-15 Pa · s, TI value is 1.0-
It is in the range of 8.0. When such a value is satisfied, the enamel particles are not destroyed by shear stress during coating, and a large circular pattern can be formed on the surface to be coated. In particular, the viscosity is 0.3 to 10 Pa.
When the s and TI values are 2.0 to 6.0, the effects described above are stably exhibited, which is preferable.

If the viscosity at 20 rpm (the guide value at the fourth rotation) is lower than 0.2 Pa · s, the particles are greatly deformed by shear stress, and it is impossible to form a circular pattern. Or the pattern formed on the surface to be coated tends to flow, resulting in a loss of design. Conversely, when it is higher than 15 Pa · s, the fluidity is poor, and when the enamel composition (I) is dispersed in an aqueous solution containing polyvinyl alcohol, it is difficult to form spherical enamel particles. It tends to be difficult to form a circular pattern. On the other hand, if the TI value is 1.
If it is smaller than 0, the pattern formed on the surface to be coated tends to flow even if the viscosity is 0.2 to 15 Pa · s, and if it is larger than 8.0, the shear stress at the time of painting causes
There is a possibility that the enamel particles will be crushed and scattered and painted.

[Enamel Composition (I)] The enamel composition (I) of the present invention comprises the above-mentioned components,
Although the amount of use is not particularly limited, the ratio of each component is as follows: the synthetic resin (A) is 100 parts by weight of solid content, the coloring material (B) is about 10 to 100 parts by weight, and the solvent is (C). ) About 100 to 1000 parts by weight is a design property,
It is desirable from the viewpoint of high weather resistance. When the viscosity adjuster (D) is added, the synthetic resin (A) is added at a ratio of about 1 to 10 parts by weight with respect to 100 parts by weight of the solid content. It is preferred to do so.

The enamel composition (I) of the present invention may contain a fibrous substance and a filler to such an extent that the above effects are not impaired. Examples of such a fibrous substance include pulp fiber, cellulose fiber, sepiolite, wollastonite and the like, and examples of the filler include calcium carbonate, talc, clay, white carbon, gypsum, barium sulfate, mica and the like.

In addition, various additives usually blended in paints, for example, thickeners, plasticizers, drying regulators, ultraviolet absorbers, gloss regulators, pigment dispersants, defoamers, antioxidants, and fungicides Agents, preservatives, film-forming auxiliaries and the like may be appropriately blended to such an extent that the effects of the present invention are not impaired.

[Enamel Particle Dispersion] In the enamel particle dispersion of the present invention, the enamel composition (I) contains polyvinyl alcohol at a concentration of 0.01 to 5% by weight and has a pH of 6 to 6 containing boric acid. No. 11 in an aqueous dispersion medium (II).

[Method for Producing Enamel Particle Dispersion] The method for producing the enamel particle dispersion of the present invention is not particularly limited. For example, an enamel composition (I) is added to a polyvinyl alcohol aqueous solution having a concentration of 0.01 to 5% by weight. ) Can be obtained by adding boric acid with or after dispersing. Before or after the addition of boric acid, the pH is adjusted to 6 to 11.

When the enamel composition (I) is dispersed in an aqueous polyvinyl alcohol solution, the previously prepared enamel composition is stirred while stirring the dispersion stabilizer-containing aqueous solution in a stirring tank with a mixing and dispersing device such as an impeller. Can be gradually added. At this time, appropriately adjust the size of the stirring tank and the shape and size of the impeller, and the peripheral speed,
The particle size of the enamel particles is adjusted by appropriately setting the compounding time of the enamel composition.

The particle diameter of the enamel particles is 0.01 to 10 m
m is preferable. In particular, when the maximum particle diameter of the enamel particles is set to 1 to 10 mm, a multicolor paint that forms a large and beautiful multicolor paint film can be manufactured. When the enamel particle size is smaller than 0.01 mm, the colorfulness of the formed film is not so much expressed. On the other hand, when the enamel particle diameter is larger than 10 mm, problems such as a decrease in storage stability and the occurrence of uneven coating are liable to occur, which tends to lack practicality.

The mixing ratio of the aqueous polyvinyl alcohol solution and the enamel composition (I) is such that the weight ratio of (aqueous polyvinyl alcohol solution / enamel composition (I)) is 1 / 0.5 to 1 / 0.5.
3 is desirable.

[Polyvinyl Alcohol] The polyvinyl alcohol is not particularly limited, but the use of cationic polyvinyl alcohol is particularly preferred because the effect of storage stability is further improved. In addition, cationic polyvinyl alcohol is excellent in antifouling property and antifungal property.

Such a cationic polyvinyl alcohol can be prepared by, for example, a method for post-modifying a polyvinyl alcohol polymer by aminoacetalization described in Japanese Patent Publication No. 30-5563. A method for producing cationic polyvinyl alcohol containing a quaternary ammonium salt by reacting glycidyltrimethylammonium chloride with polyvinyl alcohol in the presence of an alkali catalyst described in JP-B-57-34842; JP-A-56-14504 and JP-A-56-884
No. 113 and JP-A-56-118997, a copolymer of aminoalkyl (meth) acrylamide, aminoalkyl (meth) acrylate (or a quaternary ammonium salt thereof) and vinyl acetate is saponified to form a cationic polymer. A method for obtaining polyvinyl alcohol, and further, as described in JP-A-59-135202, N- (3-allyloxy-2-hydroxypropyl) dimethylamine, N- (3-allyloxy-2-hydroxy-2-methyl) Partially or completely saponify copolymers of cationic monomers such as propyl) dimethylamine, N- (4-allyloxy-3-hydroxybutyl) dimethylamine and their quaternary ammonium salts with alkyl vinyl esters. And the like obtained by such a method.

The weight average molecular weight of polyvinyl alcohol is 10,000 to 100,000, and the saponification degree is 80 to 10.
0 is preferred. When the weight average molecular weight is lower than 10,000, the strength of the partition walls due to the cross-linking of polyvinyl alcohol on the surface of the enamel particles is too weak, and the enamel particles tend to unite during storage. When the weight average molecular weight is higher than 100,000, adsorption on the surface of the enamel particles becomes insufficient, and as a result, the strength of the partition walls tends to be weakened. Further, when the degree of saponification of polyvinyl alcohol is smaller than 80, the crosslinking density of the partition walls formed by crosslinking is too low, the strength of the partition walls is weakened, and each enamel particle is united with each other at the time of storage, or painted. In some cases, enamel particles are crushed apart and a clear design pattern may not be formed.

The concentration of the aqueous polyvinyl alcohol solution is 0.1.
01 to 5% by weight. When the concentration of the aqueous polyvinyl alcohol solution is lower than 0.01% by weight, the disperse phases are united with each other and enamel particles become large, so that the dispersion cannot be performed stably and storage stability tends to decrease. If it is higher than 5% by weight, the particle size of the enamel particles becomes too small, and the dispersed phase may not be stably dispersed at the target particle size, so that it may be difficult to form a clear design pattern.

[Boric acid] Boric acid is an oxygen acid generated by hydration of diboric acid trioxide, and includes orthoboric acid, metaboric acid and tetraboric acid. Also, sodium tetraborate (borax) can be used. As described later, the boric acid is added simultaneously with or after the raw material enamel of the enamel particles is dispersed in the aqueous dispersion medium. On the surface of the enamel particles dispersed to a specified size by the addition of boric acid, the polyvinyl alcohol adsorbed on the surface reacts with boric acid to form a very thin gel-like film, and the enamel particles are united with each other. And make it strong. At the same time, polyvinyl alcohol diluted dilutely in the aqueous dispersion medium also reacts with boric acid to form a loose network. With this network, the enamel particles and the coloring material in the aqueous dispersion medium can be stably dispersed without settling.

The amount of boric acid to be added is not particularly limited as long as the crosslinking reaction with polyvinyl alcohol is sufficiently carried out.
The amount is preferably about 0.01 to 10 parts by weight with respect to parts by weight.

The medium of the aqueous dispersion medium (II) includes
Water is mainly used, but an organic solvent which is easily soluble in water can also be used. In the aqueous polyvinyl alcohol solution, various additives usually blended in the paint, for example, a thickener, a plasticizer, a preservative, a drying regulator, a dispersant, an ultraviolet absorber and the like are appropriately added to the extent that the effects of the present invention are not impaired. You may mix.

To add boric acid, specifically, a method of adding boric acid while dispersing the enamel composition (I) while stirring the aqueous polyvinyl alcohol solution, or adding the enamel composition (I) to the aqueous polyvinyl alcohol solution Is distributed,
Further, a method of adding boric acid or the like can be employed.
The reaction between polyvinyl alcohol and boric acid proceeds stably when the pH of the system is in the range of 6 to 11. The timing for performing the pH adjustment is not particularly limited, and may be before or after the boric acid is added.

The pH adjusting agent for adjusting the pH to 6 to 11 is as follows:
Although not particularly limited, for example, ammonia, 1-aminoethanol, 2-aminoethanol,
-Amino-2-propanol, 2-amino-1-propanol, 3-amino-1-propanol, 2-amino-
2-methyl-1-propanol, 2- (methylamino)
-2-methyl-1-propanol, N, N-dimethylethanolamine, N, N-diethylethanolamine,
N- (2-aminoethyl) ethanolamine, N-methylethanolamine, N-methyldiethanolamine and the like can be mentioned.

By setting the pH within the above range, the storage stability of the enamel particle dispersion is sufficiently ensured. pH
Is smaller than 6, the reaction between boric acid and polyvinyl alcohol (b) does not proceed. When the pH is higher than 11, the polyvinyl alcohol is aggregated and gelled, and it becomes impossible to reinforce the enamel particles by the reaction with boric acid or form a network in the aqueous dispersion medium. This tendency is particularly remarkable in the case of cationic polyvinyl alcohol. As a result, when the pH is out of the range of 6 to 11, the dispersion stability of the enamel particles and the coloring material cannot be secured. The enamel particle dispersion does not deteriorate during storage, maintains the above-mentioned gradual network of polyvinyl alcohol, and adheres to the surface to be coated and displaces the surface during coating when forming a multi-color paint coating. It has the effect of following.

[Aqueous Dispersion Medium (II)] The aqueous dispersion medium (II) for forming the enamel particle dispersion of the present invention contains polyvinyl alcohol and a crosslinking agent in addition to the aqueous medium, as well as an antifoaming agent, a thickener, Known additives such as dispersants, fungicides, preservatives, pH adjusters, ultraviolet absorbers, and antioxidants can be added as long as the effects of the present invention are not impaired. Further, a synthetic resin emulsion may be included.

The aqueous dispersion medium (II) in the present invention is JIS
K5660 "Shiny synthetic resin emulsion paint" 4.8 It is preferable to form a coating film having a hiding factor of 0.05 to 0.60. In order to adjust the hiding ratio of the aqueous dispersion medium (II) to the above range, for example, there is a method of including a coloring material in the aqueous dispersion medium (II). As the coloring material, the same coloring material (B) as the above-mentioned enamel particles can be used. The amount is appropriately determined so that the film formed by the aqueous dispersion medium (II) falls within the above-mentioned hiding ratio. Further, among the coloring materials (B), those having a particle diameter of 1 μm or less can be more preferably used because the enamel particles have a deep and luxurious atmosphere with a deep hue.

When the hiding ratio is smaller than 0.05, the composite effect of the hue of the dispersion medium and the hue of the enamel particles cannot be obtained,
Only spotted patterns of enamel particles are formed. When the hiding ratio is larger than 0.60, the hue of the enamel particles becomes unclear, and a monochromatic coating of the hue of the dispersion medium is formed.

[Multicolor paint composition] The multicolor paint composition of the present invention is formed from a dispersion of enamel particles of two or more colors. In order to obtain such a multicolor paint having two or more colors, first, an enamel dispersion liquid in which single-color enamel particles are dispersed as described above is appropriately prepared. Then, by mixing the enamel dispersions of each color produced by the same method, a multi-colored paint can be obtained.

Further, in the multicolored paint of the present invention,
By using a multicolor paint composition in which enamel particles having a relatively large particle diameter and enamel particles having a relatively small particle diameter and a different color are mixed, there is an effect that a large pattern can be clearly seen. This is because when forming a multi-pattern coating film, enamel particles having a large particle diameter form a large pattern, and a coating film is formed between the patterns so that the enamel particles having a small particle diameter are filled. This is because it becomes a color.

[Coating Method] The site to which the multicolor paint composition of the present invention is applied is not particularly limited. For example, metal, glass, porcelain tile, concrete, mortar, siding board, ALC board, extrusion molding It can be used as a surface finishing material for various substrates such as plates and plastic plates. It is mainly used to protect buildings such as buildings and civil engineering structures.

The multicolor paint composition of the present invention is subjected to a surface treatment, if necessary, on a substrate, and then coated. The coating amount is usually about 0.2 to 1.0 kg / m ² .
In addition, as the coating device, a known device such as a spray gun, a roller, or a brush can be used.

The multicolor paint composition of the present invention can be used as the outermost layer coating film. If necessary, a transparent top coat may be further laminated. Such a transparent top coat does not necessarily have to be colorless, and if the color clear has a slight hue, it becomes possible to further enhance the aesthetic appearance in combination with the hue of the multicolored pattern coating film. The clear paint is not particularly limited, and a known paint can be used. A slightly colored one can also be used. Examples of the type of resin include acrylic resin, urethane resin, acrylic silicon, and fluorine. In consideration of weather resistance, acrylic silicon type, fluorine type and the like are preferable. The coating with the clear coating may be performed by a known coating, and can be performed by various coating methods such as spray coating, roller coating, and brush coating. The application amount of the clear paint may be appropriately set according to the application site and the like, and is usually about 0.1 to 0.4 kg / m ² .

[0068]

The enamel particle dispersion used for preparing the multicolor paint composition of the present invention has a storage stability due to the fact that the aqueous dispersion medium (II) contains polyvinyl alcohol and boric acid as dispersion stabilizers. Good. Although the mechanism is not clear, the polyvinyl alcohol adsorbed on the surface of the enamel particles causes cross-linking to form a partition surrounding the enamel particles. In particular, by regulating the degree of polymerization, the degree of saponification, and the concentration of polyvinyl alcohol, the amount of polyvinyl alcohol molecules adsorbed on the surface of the enamel particles is controlled, and then boric acid is used. Can be controlled. The partition walls of the particles thus obtained can have a moderately soft property.

In the present invention, the enamel composition (I)
By using a material adjusted to a specific viscosity, it is difficult for sedimentation and coalescence of the dispersed particles to occur during storage even if the particle size of the dispersed particles is large, excellent in storage stability, and painted after long-term storage Can provide a multicolor paint composition that forms a smooth coating film without deteriorating its design. Such a multi-color paint composition,
Due to the combined effect of the surface crosslinkability of the enamel particles and the internal viscosity, even when shear stress is applied during spray coating, the enamel particles are only deformed without crushing and bursting, and the coating equipment has changed Even under various conditions in the case, the formed coating film is unlikely to change. In addition, when the particles collide with the surface to be coated, the particles are easily crushed, and the enamel composition inside spreads widely, and thereafter keeps a circular pattern without flowing. In the coating film formed in this manner, the patterns of the respective colors are large and circular and overlap without any gap, and the finish is highly aesthetic.

Further, by using a specific hiding ratio as the aqueous dispersion medium (II) of the enamel particle dispersion of the present invention, the difference in hue between the color particles is not so clear, and the hue is continuous and subtle. Is varied, and a multi-color pattern paint composition capable of obtaining a multi-color pattern design with modest and deepness can be provided.

[0071]

EXAMPLES Test Examples 1 to 4 are shown below, and the features of the present invention are further clarified by Examples and Comparative Examples. All parts and numerical values in the table are parts by weight and% by weight.
It is.

Table 1 shows materials used in Examples and Comparative Examples.

[Table 1]

Test Example 1 Test Example 1 is a test for confirming storage stability, which will be clarified by Examples and Comparative Examples. The storage stability is as shown below.

(Initial state of paint) Immediately after the production of the colorful paint, the state of the paint when mixed slowly was confirmed visually according to JIS K 5667 “Color paint” 5.3 “State in container”. . The evaluation was as follows: ：: No abnormality, ×: (Lump generation, gelation, abnormal thickening, etc.).

(Storage stability test) A multi-color paint was applied at 50 ° C.
After being left in the incubator for 1 month, when the mixture was stirred slowly in the same manner as described above, the state of the paint was visually checked.
The evaluation was as follows: ：: No abnormality, ×: (Lump generation, gelation, abnormal thickening, etc.).

(Production of aqueous solution of polyvinyl alcohol)

[Table 2] Using the raw materials shown in Table 1, a polyvinyl alcohol aqueous solution was produced in the formulation examples shown in Table 2. here,
Formulation Example 1, Formulation Example 4, Formulation Example 7 is an example using polyvinyl alcohol, Formulation Example 2, Formulation Example 3, Formulation Example 8 is an example using cationic polyvinyl alcohol, and Formulation Example 5 is an example using a polyvinyl alcohol aqueous solution. An example in which the concentration of the cationic polyvinyl alcohol aqueous solution is higher than the range specified in the present invention is used. In addition, all the numerical values of Table 2 were shown by weight part except density | concentration.

(Production of Enamel Composition)

[Table 3] Using the raw materials shown in Table 1, each enamel composition was manufactured in Formulation Examples 9 to 17 (excluding the crosslinking agent) shown in Table 3. Here, formulation examples 9, 12, and 15 were white, formulation examples 10, 13, and 16 were cream, and formulation examples 11, 14, and 17 were pink. In addition, all the numerical values of Table 3 were shown by weight part.

(Manufacture of colorful paints)

[Table 4] Using the raw materials shown in Table 1, using each of the formulation examples shown in Tables 2 and 3, with the aqueous polyvinyl alcohol solution or the cationic polyvinyl alcohol aqueous solution shown in Table 4,
A multicolor paint composition was produced in combination with the enamel composition. As a production procedure, after dispersing each enamel composition while stirring the aqueous polyvinyl alcohol solution or the aqueous cationic polyvinyl alcohol solution,
The crosslinker was mixed. Then, Example 1 was used as a pH adjuster.
From Example 4, Comparative Example 1, Comparative Example 2, Comparative Example 4 and Comparative Example 5, aminomethylpropanol was used in Comparative Example 3
Was adjusted for pH using lactic acid. The aqueous solution of polyvinyl alcohol or the aqueous solution of cationic polyvinyl alcohol was mixed with each enamel composition such that the weight ratio was 1: 1.5. In this way, after each monochromatic enamel particle dispersion is manufactured, the monochromatic enamel particle dispersion is finally mixed in the combinations of Examples and Comparative Examples in Table 4 to obtain a multicolor paint composition. Manufactured. Table 5 shows the results of the evaluation of the obtained multi-color paint composition with respect to the above evaluation items.

[0079]

[Table 5]

(Test Example 1: Examples 1 and 2) Since the concentration of polyvinyl alcohol or cationic polyvinyl alcohol and the pH of the system were within the ranges specified by the present invention, the produced multi-color paint was produced after the production. Even in the initial state, even after the storage stability test, there is no coalescence or sedimentation of the enamel particles, and a film formed on the surface of the enamel particles by the reaction between polyvinyl alcohol or cationic polyvinyl alcohol and boric acid. It was found that the effect of preventing sedimentation by network formation in the aqueous dispersion medium was exhibited. When this multi-color paint was applied, a very large multi-color film of an acrylic ester-methacrylic ester copolymer mixed with white, cream and pink was formed.

(Test Example 1: Example 3) Since the concentration of the cationic polyvinyl alcohol and the pH of the system were within the ranges specified by the present invention, the produced colorful paint was in an initial state after the production. Even after the storage stability test, there is no coalescence or sedimentation of the enamel particles, and the film formed on the surface of the enamel particles by the reaction between the cationic polyvinyl alcohol and boric acid, and in the aqueous dispersion medium. It was found that the effect of preventing sedimentation by network formation was exhibited.
When the multicolored paint was applied, a multicolored acrylic-resin-based multicolored film was formed.

(Test Example 1: Example 4) Since the concentration of polyvinyl alcohol and the pH of the system were within the ranges specified by the present invention, the produced multi-color paints were in an initial state after production. Even after the storage stability test, there is no coalescence or sedimentation of the enamel particles, and the reaction between polyvinyl alcohol and boric acid causes the film formed on the surface of the enamel particles and sedimentation due to network formation in the aqueous dispersion medium. It turned out that the prevention effect was exhibited. Applying this multi-color paint, acrylic silicone resin white, cream color,
A multi-pattern film with a relatively fine pattern mixed with pink was formed.

Test Example 1: Comparative Example 1 As a result of using an aqueous dispersion medium in which the concentration of polyvinyl alcohol was lower than the concentration specified in the present invention, the maximum particle diameter of the enamel particles was 15.
It became very large at 0 mm, and the viscosity was slightly increased immediately after the production of the multicolored paint, but gelled after the storage stability test.

(Test Example 1: Comparative Example 2) As a result of using an aqueous dispersion medium in which the concentration of the cationic polyvinyl alcohol was higher than the concentration specified in the present invention, the maximum particle diameter of the largest particles of the enamel was as small as 0.2 mm. Immediately after the production of the multicolor pattern paint, slight increase in viscosity was observed, but after the storage stability test, the viscosity increased abnormally.

(Test Example 1: Comparative Example 3) Since the pH of the system is lower than the range specified in the present invention, the reaction between polyvinyl alcohol and boric acid hardly occurs, and the film formation on the surface of the enamel particles and the aqueous dispersion Network formation in the medium became impossible, and sedimentation and gelation occurred immediately after the production of the enamel particles.

(Test Example 1: Comparative Example 4) Since the pH of the system was higher than the range specified in the present invention, the cationic polyvinyl alcohol gelled. The enamel composition could not be dispersed to form particles.

Test Example 1: Comparative Example 5 Enamel particles were produced in the same manner as in Example 1 except that aluminum tris (acetylacetonate) was used as a crosslinking agent. Has undergone a hydrolysis reaction, and thus has gelled in the storage stability test.

Test Example 2 Test Example 2 is a test for confirming the appearance of the coating film in addition to the storage stability, and is clarified by Examples (Reference Examples) and Comparative Examples. The test of the coating film appearance and the storage stability are as shown below.

(Initial state of paint) Immediately after producing the colorful paint, according to JIS K 5667 "Color paint" 5.3 "State in container", the state of paint when stirred slowly was visually checked. . The evaluation was ○: no abnormality, ×: abnormal (lumps, gelation, abnormal thickening, etc.).

(Storage stability test)
After being left in the incubator for 1 month, the state of the paint when slowly stirred as described above was visually confirmed. The evaluation was as follows: ○: No abnormality, ×: Abnormal (Lump generation, gelation,
Abnormal thickening, etc.).

(Appearance of coating film) The multicolor paint composition before and after storage was applied to a slate plate in an amount of 0.3 kg /
spray painting m ^2, and the dried-curing at room temperature to evaluate the coating film appearance visually. The evaluation was ○: an appearance in which the color tone changes continuously and slightly, ×: an appearance in which the contrast of the color particles is clear, or a monochromatic and monotonous appearance.

(Production of aqueous solution of polyvinyl alcohol)

[Table 6] Using the raw materials shown in Table 1, a polyvinyl alcohol aqueous solution was produced in the formulation examples shown in Table 6. In addition, all the numerical values of Table 6 were shown by weight part except density | concentration.

(Production of Enamel Composition)

[Table 7] Each enamel composition was manufactured using the raw materials shown in Table 1 and in the composition shown in Table 7 (excluding the crosslinking agent). In addition, all the numerical values of Table 7 were shown by weight part.

(Manufacture of colorful paints)

[Table 8] Using the respective formulation examples shown in Tables 6 and 7, a multi-pattern paint composition was produced by combining the aqueous polyvinyl alcohol solution shown in Table 8 with the enamel composition. As a production procedure, each enamel composition was dispersed while stirring an aqueous polyvinyl alcohol solution, and then a crosslinking agent shown in Table 7 was mixed. Thereafter, pH was adjusted using aminomethylpropanol for Examples 1-4, Reference Examples 1-4, and Comparative Examples 2-3 as a pH adjuster, and lactic acid for Comparative Example 1. The aqueous polyvinyl alcohol solution and each of the enamel compositions were mixed at a weight ratio of 1: 1.5. The hiding ratio in Table 8 is a value obtained by separately mixing an aqueous solution of polyvinyl alcohol and a crosslinking agent, and measuring by the method specified in the present invention.

As described above, the mono-colored enamel particle dispersions were manufactured, and finally, the mono-colored enamel particle dispersions were mixed in the combinations of Examples and Comparative Examples shown in Table 8 to obtain a multi-color paint. A composition was prepared. Table 9 shows the results of the evaluation of the obtained multi-pattern paint composition with respect to the above evaluation items.

[0096]

[Table 9]

(Test Example 2: Examples 1 and 2) A multicolor paint composition in which white enamel particles are dispersed in a black aqueous dispersion medium, and the formed coating film has a continuous gray color tone. The appearance changed subtly and subtly. It was also excellent in storage stability, and a coating film having the same appearance as in the initial stage could be obtained even after coating after storage.

(Test Example 2: Example 3) A multicolor paint composition in which white enamel particles and gray enamel particles are dispersed in a yellow aqueous dispersion medium, and the formed coating film is beige. The color tone changed continuously and slightly. It was also excellent in storage stability, and a coating film having the same appearance as in the initial stage could be obtained even after coating after storage.

(Test Example 2: Example 4) A multi-color paint composition in which gray enamel particles are dispersed in a white aqueous dispersion medium, and the formed coating film has a continuous gray color tone. The appearance changed slightly. It was also excellent in storage stability, and a coating film having the same appearance as in the initial stage could be obtained even after coating after storage.

(Test Example 2: Reference Example 1) A multi-color paint composition in which gray enamel particles are dispersed in a white aqueous dispersion medium, but the hiding ratio of the aqueous dispersion medium is high. Had a white, monotonous appearance.

(Test Example 2: Reference Example 2) A multi-color paint composition in which white enamel particles and gray enamel particles are dispersed in an aqueous dispersion medium containing no pigment. The contrast between the grains and the gray grains became clear.

(Test Example 2: Comparative Example 1) As a result of using an aqueous dispersion medium in which the concentration of polyvinyl alcohol was lower than the concentration specified in the present invention, a slight increase in the viscosity was observed immediately after the production of the multicolor paint. However, it settled and coalesced after the storage stability test.

(Test Example 2: Comparative Example 2) As a result of using an aqueous dispersion medium in which the concentration of the cationic polyvinyl alcohol was higher than the concentration specified in the present invention, a slight increase in the viscosity was observed immediately after the production of the colorful paint. However, the viscosity increased abnormally after the storage stability test.

(Test Example 2: Comparative Example 3) The pH of the system was lower than the range specified in the present invention and settled and coalesced immediately after the production of the enamel particles.

(Test Example 2: Comparative Example 4) The pH of the system was higher than the range specified in the present invention, and the cationic polyvinyl alcohol gelled, whereby the enamel composition could be dispersed to form particles. Did not.

Test Example 2: Comparative Example 5 When aluminum tris (acetylacetonate) was used as a crosslinking agent, it gelled in a storage stability test.

Test Example 3 Test Example 3 is a test for confirming the appearance of the coating film and the weather resistance in addition to the storage stability. This is clarified by Examples (Reference Examples) and Comparative Examples. The storage stability, coating film appearance and weather resistance test are as shown below.

(Storage stability test) The paint was allowed to stand in a room at 20 ° C. for one month, and the condition when the paint was slowly stirred according to JIS K 5667 “Colorful paint” 5.3 “Condition in a container” was confirmed. did. The evaluation was ○: no abnormality, ×: abnormal (lumps, gelation, abnormal thickening, etc.).

(Coating film appearance test, weather resistance test) JIS K 5667
Based on "Multi-color paint" 5.11 "Weather resistance", synthetic resin emulsion paint specified in JIS K 5663 is applied to a flexible board (900 x 900 x 6 mm) in a required amount of 0.2 k.
g / m ² with a brush, dried and cured for 24 hours, then hold the flexible board vertically, and spray-paint each colorful pattern paint with a ricin gun at a required amount of 0.4 kg / m ² Then, what was dried and cured for 24 hours was used as a test body. Two test pieces were prepared. The appearance of the pattern formed on the test body was visually confirmed. Evaluation,
：: The pattern was clear, the color of each enamel particle was large and circular, and X: the pattern was unclear.

Subsequently, each of the test pieces using the acrylic silicone resin was 300 mm × 150 m from each test piece.
Two test pieces of m were cut out, and one of them was used as a sample plate, and the other one was subjected to a 12-month exposure test. Evaluation,
：: No abnormality, ×: Chalking occurred.

(Production of aqueous solution of polyvinyl alcohol)

[Table 10] Using the raw materials shown in Table 1, each polyvinyl alcohol aqueous solution was produced according to the formulation examples shown in Table 10. here,
Formulation Example 2 is an example in which the weight average molecular weight is lower than the range specified by the present invention, Formulation Example 3 is an example in which the saponification degree is lower than the range specified in the present invention, Formulation Example 4
Is an example in which the concentration of polyvinyl alcohol is lower than the range specified by the present invention, and Formulation Example 5 is an example in which the concentration of polyvinyl alcohol is higher than the range specified by the present invention. The numbers in Table 10 are shown in parts by weight.

(Production of Enamel Composition)

[Table 11]

[Table 12] Using the raw materials shown in Table 1, each enamel composition was produced according to the formulation examples shown in Tables 11 and 12. here,
Formulation Examples 6 to 9 are blue, yellow, red,
All are enamel compositions that are white and within the specified range of the present invention. On the other hand, Formulation Example 10 is white, but its acid value is larger than the specified range of the present invention. Formulation Example 1
Examples 1 to 13 are white, blue, and yellow, respectively, and all used an acrylic resin. Formulation Examples 14 to 16 are white, blue, and red, respectively, and Formulation Example 15 has a viscosity at 20 rpm smaller than the range specified in the present invention. Formulation Examples 17 to 19
Are white, yellow, and red. Among them, Formulation Examples 17 and 19 have TI values larger than the specified range of the present invention. Formulation Examples 20 to 22 are white, yellow, and red, but all have TI values smaller than the specified range of the present invention. The numbers in Tables 11 and 12 are shown in parts by weight except for the viscosity and the TI value.

(Manufacture of colorful paints)

[Table 13] Using the respective formulation examples shown in Table 10, Table 11, and Table 12, an enamel particle dispersion was produced by combining the aqueous polyvinyl alcohol solution shown in Table 13 with the enamel composition. As a production procedure, the crosslinking agent 1 was mixed after dispersing each enamel composition while stirring the aqueous polyvinyl alcohol solution. At this time, the crosslinking agent 1 was mixed at a ratio of 0.5% by weight to the solid content of polyvinyl alcohol.

Thereafter, as a pH adjuster, aminomethylpropanol was used for Examples 1 to 4, Reference Examples 1 to 5 and Comparative Examples 1 to 3 and for Comparative Example 4, lactic acid was used for pH adjustment. Adjustments were made. The polyvinyl alcohol aqueous solution and each enamel composition are in a weight ratio of 1:
The mixture was mixed to 1.5.

As described above, after preparing the monochromatic enamel particle dispersions, the monochromatic enamel particle dispersions were finally mixed in each combination shown in Table 5 to produce a multicolor pattern paint composition. In addition, Formulation Example 10 could not produce an enamel particle dispersion. Table 1 shows the evaluation results of the obtained multi-pattern paint composition according to the above evaluation items.
4 and Table 15.

[0116]

[Table 14]

[Table 15]

(Test Example 3: Examples 1 to 4) Example 1 is blue, yellow, red, Example 2 is blue, red, white, Example 3 is blue, yellow, white, Example 4 Had a multicolored pattern in which three colors of white, blue, and yellow were respectively independent and alternately overlapped. In addition, the enamel particles of each color formed a large circular pattern, and a colorful pattern could be clearly recognized even at a long distance. Examples 1, 2, and 3
Good results were obtained in the weather resistance test.

(Test Example 3: Reference Example 1) Since polyvinyl alcohol having a weight average molecular weight lower than the specified range of the present invention was used, the partition wall strength on the surface of the enamel particles became insufficient, resulting in poor storage stability test. It became.

(Test Example 3: Reference Example 2) Since polyvinyl alcohol having a degree of saponification lower than the specified range of the present invention was used, the partition wall strength on the surface of the enamel particles became insufficient, resulting in poor storage stability. Was.

(Test Example 3: Comparative Example 1) Since the concentration of the aqueous polyvinyl alcohol solution was lower than the specified range of the present invention, the partition wall strength on the surface of the enamel particles was insufficient, resulting in poor storage stability. Was.

(Test Example 3: Comparative Example 2) Since the concentration of the polyvinyl alcohol aqueous solution was higher than the specified range of the present invention, the enamel particles were miniaturized, and the pattern of the resulting coating film was unclear. When viewed from a long distance, the colorful patterns could not be distinguished.

(Test Example 3: Reference Example 3) Since the blue enamel composition (Formulation Example 15) had a viscosity of 20 rpm lower than the range specified in the present invention, the blue portion of the formed multi-colored coating film was not removed. As a result, a circular pattern was not formed, and the design was reduced.

(Test Example 3: Reference Example 4) White enamel composition (Formulation Example 17), red enamel composition (Formulation Example 19)
Is higher than the range specified by the present invention, the viscosity of this enamel composition becomes very thixotropic, and the shear stress during spray coating causes the particles to be crushed apart and to be scattered finely. As a result, a large pattern could not be formed, and the colorful pattern became unclear.

(Test Example 3: Reference Example 5) White enamel composition (Formulation Example 20), yellow enamel composition (Formulation Example 2)
1), the TI value of the red enamel composition (Formulation Example 22)
Since it is lower than the range specified by the present invention, the viscosity of this enamel composition becomes very dilatant, and the enamel particles in the multi-colored paint will flow after colliding with the surface to be coated, forming a large circular pattern. And the colorful pattern became unclear. In addition, there was a gap between the enamel particles, and a portion through which the undercoat was transparent was observed. as a result,
Chalking occurred in the transparent part in the weather resistance test.

(Test Example 3: Comparative Example 3) Since the pH of the system was higher than the range specified in the present invention, polyvinyl alcohol gelled. The enamel composition could not be dispersed to form particles.

(Test Example 3: Comparative Example 4) Since the pH of the system was lower than the range specified in the present invention, the particles settled immediately after the production of the enamel particles and were united.

Test Example 4 Test Example 4 is a test for confirming the appearance of the coating film in addition to the storage stability, and is clarified by Examples (Reference Examples) and Comparative Examples. The storage stability and the coating film appearance test are as shown below.

(Initial state of paint) Immediately after the production of the colorful paint, the state of the paint when mixed slowly was confirmed visually according to JIS K 5667 “Color paint” 5.3 “State in Container”. . The evaluation was ○: no abnormality, ×: abnormal (lumps, gelation, abnormal thickening, etc.).

(Storage stability test) A multi-colored paint was applied at 50 ° C.
After being left in the incubator for 1 month, the state of the paint when slowly stirred as described above was visually confirmed. The evaluation was as follows: ○: No abnormality, ×: Abnormal (Lump generation, gelation,
Abnormal thickening, etc.).

(Appearance of coating film) The multicolor paint composition before and after storage was applied to a slate plate in an amount of 0.3 kg /
spray painting m ^2, and the dried-curing at room temperature to evaluate the coating film appearance visually. The evaluation was ○: an appearance in which the color tone changes continuously and slightly, ×: an appearance in which the contrast of the color particles is clear, or a monochromatic and monotonous appearance.

(Production of aqueous solution of polyvinyl alcohol)

[Table 16] Using the raw materials shown in Table 1, each polyvinyl alcohol aqueous solution was produced according to the formulation examples shown in Table 16. Table 16
Are shown in parts by weight except for the concentration.

(Production of Enamel Composition)

[Table 17] Using the raw materials shown in Table 1, each enamel composition was produced according to the formulation examples shown in Table 17. The numbers in Table 17 are all shown in parts by weight except for the viscosity and the TI value.

(Manufacture of colorful paints)

[Table 18] Using the respective formulation examples shown in Tables 16 and 17, enamel particle dispersions were produced in combinations shown in Table 18. As a production procedure, the crosslinking agent 1 was mixed after dispersing each enamel composition while stirring the aqueous polyvinyl alcohol solution. At this time, the crosslinking agent 1 was mixed at a ratio of 0.5% by weight to the solid content of polyvinyl alcohol. Then p
Aminomethylpropanol was used for Examples 1 to 4, Reference Examples 1 to 7, and Comparative Examples 1, 2 and 4 as an H adjuster, and pH was adjusted for Comparative Example 3 using lactic acid. The aqueous polyvinyl alcohol solution and each of the enamel compositions were mixed at a weight ratio of 1: 1.5. Table 1
The hiding ratio in 8 is a value obtained by separately mixing an aqueous solution containing a dispersion stabilizer (aqueous solution of polyvinyl alcohol) and a crosslinking agent and measuring by the method defined in the present invention.

As described above, after the mono-colored enamel particle dispersions were produced, the mono-colored enamel particle dispersions were finally mixed in each combination shown in Table 4 to produce a multi-color paint composition. In addition, Formulation Example 15 could not produce an enamel particle dispersion. Table 19 shows the results of the evaluation of the obtained multi-color paint composition with respect to the above evaluation items.
Shown in

[0135]

[Table 19]

(Test Example 4: Examples 1 and 2) A multicolor paint composition in which white enamel particles were dispersed in a black aqueous dispersion medium, and the formed coating film had a continuous gray color tone. The appearance changed subtly and subtly. It was also excellent in storage stability, and a coating film having the same appearance as in the initial stage could be obtained even after coating after storage.

(Test Example 4: Example 3) A multicolor paint composition in which white enamel particles and gray enamel particles are dispersed in a yellow aqueous dispersion medium, and the formed coating film is beige. The color tone changed continuously and slightly. It was also excellent in storage stability, and a coating film having the same appearance as in the initial stage could be obtained even after coating after storage.

(Test Example 4: Example 4) A multi-color paint composition in which gray enamel particles are dispersed in a white aqueous dispersion medium, and the formed coating film has a continuous gray tone. The appearance changed slightly. It was also excellent in storage stability, and a coating film having the same appearance as in the initial stage could be obtained even after coating after storage.

(Test Example 4: Reference Example 1) A multi-color paint composition in which gray enamel particles are dispersed in a white aqueous dispersion medium. Had a white, monotonous appearance.

(Test Example 4: Reference Example 2) A multi-color paint composition in which white enamel particles and gray enamel particles were dispersed in an aqueous dispersion medium containing no pigment, and the formed coating film was white The contrast between the grains and the gray grains became clear.

(Test Example 4: Comparative Example 1) As a result of using an aqueous dispersion medium in which the concentration of polyvinyl alcohol was lower than the concentration specified in the present invention, a slight increase in viscosity was observed immediately after the production of the multicolor paint. However, it settled after the storage stability test and coalesced.

(Test Example 4: Comparative Example 2) As a result of using an aqueous dispersion medium in which the concentration of polyvinyl alcohol was higher than the concentration specified in the present invention, a slight increase in the viscosity was observed immediately after the production of the colorful paint. However, the viscosity increased abnormally after the storage stability test.

(Test Example 4: Reference Example 3) As polyvinyl alcohol having a weight average molecular weight lower than the specified range of the present invention was used, storage stability was poor.

(Test Example 4: Reference Example 4) Since polyvinyl alcohol having a degree of saponification lower than the specified range of the present invention was used, the storage stability was poor.

(Test Example 4: Comparative Example 3) The pH of the system was lower than the range specified in the present invention, and settled immediately after the production of the enamel particles and coalesced.

(Test Example 4: Comparative Example 4) The pH of the system was higher than the range specified in the present invention, and polyvinyl alcohol gelled, and the enamel composition could not be dispersed to form particles. .

(Test Example 4: Reference Example 5) Since the viscosity of the white enamel particles (Formulation Example 16) at 20 rpm was lower than the range specified by the present invention, the white portion of the formed multi-colored pattern coating film was washed away. The design has been reduced.

Test Example 4: Reference Example 6 Since the TI value of the white enamel particles (Formulation Example 17) was higher than the range specified in the present invention, the particles were pulverized into pieces at the time of spray coating and dispersed finely. The design was reduced due to the painting.

(Test Example 4: Reference Example 7) Since the TI value of the white enamel particles (Formulation Example 18) was lower than the range specified in the present invention, the white particles flowed on the surface to be coated, and the design was poor. It has dropped.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) C09D 5/30 C09D 5/30 7/14 7/14 129/04 129/04 157/00 157/00 / / (C08L 101/00 (C08L 101/00 29:04) 29:04) G (31) Priority claim number Japanese Patent Application 2000-161543 (P2000-161543) (32) Priority date May 31, 2000 ( (May 31, 2000) (33) Country of priority claim Japan (JP) (72) Inventor Yoshikazu Ishida 1-25-10 Shimizu, Ibaraki-shi, Osaka F-term in SK Chemical Research Co., Ltd. 4J002 AE033 AE053 BB253 BC031 BC091 BD041 BE022 BE041 BF011 BF021 BG011 BG041 BG061 BG071 BG101 BG121 BG131 BH021 CD191 DA026 DA036 DE106 DE116 DE136 DE146 DE236 DE239 DJ016 DJ019 DJ036 DJ039 DK008 EA017 EA027 EA057 EB027 EC037 ED027 EE037 EG019 EH037 EL109 EU026 FB009 FD096 GH01 HA08 4J038 CC021 CC081 CD021 CE022 CE051 CF011 CG021 CG061 CG141 CG161 CG171 CH031 CH121 CH141 CH171 CH201 CL001 GA03 GA07 GA09 GA12 GA15 HA026 HA036 HA156 HA216 HA286 HA446 HA476 HA526 JA02 JA05 JA09 JA19 JA26 JA33 JA56 KA06 KA08 KA09 LA03 LA14 MA08

Claims (11)

[Claims] An enamel composition (I) containing a synthetic resin (A), a coloring material (B) and a solvent (C) contains polyvinyl alcohol at a concentration of 0.01 to 5% by weight, and boric acid. A dispersion liquid of enamel particles characterized by being dispersed in an aqueous dispersion medium (II) having a pH of 6 to 11 containing 2. The enamel particle dispersion according to claim 1, wherein the polyvinyl alcohol has a weight average molecular weight of 10,000 to 100,000 and a degree of saponification of 80 to 100. 3. The enamel particle dispersion according to claim 2, wherein the polyvinyl alcohol is a cationic polyvinyl alcohol. 4. The enamel particle dispersion according to claim 1, wherein the synthetic resin (A) is a vinyl synthetic resin having an acid value of 0 to 30. 5. A coloring material (B) based on 100 parts by weight of a solid content of the synthetic resin (A) based on the enamel composition (I).
The enamel particle dispersion according to any one of claims 1 to 4, comprising 10 to 100 parts by weight and 100 to 1000 parts by weight of the solvent (C). 6. The enamel composition (I) contains a viscosity modifier (D), and at a temperature of 20 ° C., a viscosity at 20 rpm (a guide value at the fourth rotation) measured by a BH type viscometer is: The enamel according to any one of claims 1 to 5, wherein the enamel is adjusted to 0.2 to 15 Pa · s, and a TI value obtained by the following is in a range of 1.0 to 8.0. Particle dispersion. <TI value> TI value: a value obtained by using a BH-type viscometer according to Equation 1. TI value = η1 / η2 (Equation 1) (However, apparent viscosity at η1: 2 rpm (Pa ·
s: guide value at the second rotation), η2: apparent viscosity at 20 rpm (Pa · s:
Guide value at 4th rotation)) 7. The enamel particle dispersion according to claim 6, wherein the viscosity modifier (D) is contained in an amount of 1 to 10 parts by weight based on 100 parts by weight of the solid content of the synthetic resin (A). liquid. 8. The enamel particles having a maximum particle size of 1 to 10
The enamel particle dispersion according to any one of claims 1 to 7, wherein 9. The aqueous dispersion medium (II) which forms a coating film having a opacity of 0.05 to 0.60 in JIS K 5660 “Shiny synthetic resin emulsion paint” 4.8. Item 10. The enamel particle dispersion according to any one of Items 1 to 8. 10. An aqueous solution of polyvinyl alcohol having a concentration of 0.01 to 5% by weight, to which boric acid is added while or after the enamel composition (I) is dispersed, and before or after adding boric acid, The method for producing an enamel particle dispersion according to any one of claims 1 to 9, wherein the pH is adjusted to 6 to 11. 11. A multicolor paint composition comprising two or more of the enamel particle dispersions according to claim 1. Description: