JPH08311362A - Method for producing aqueous coating composition containing azo pigment - Google Patents

Abstract

(57) [Summary] [Structure] An aqueous dispersion of anionic cross-linked resin particles is added and mixed into the coupler component of the azo pigment to produce pigment particles by the coupling reaction with the diazo component and at the same time coprecipitate the resin and pigment. A method for producing an aqueous coating composition containing an azo pigment, characterized in that the pigment / resin mixed precipitate thus obtained is redispersed in an aqueous medium together with a base. [Effect] An aqueous coating composition excellent in color development, density, gloss and the like can be produced simultaneously with azo pigment synthesis. Further, in the present invention, since the dry pulverization process is not performed, the working environment associated with dust can be improved and energy can be saved.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an aqueous coating composition such as an aqueous printing ink, an aqueous paint and the like. More specifically, it relates to a method for producing an aqueous coating composition simultaneously with the synthesis of an azo pigment without the steps of drying and pulverizing the pigment.

[0002]

2. Description of the Related Art In recent years, water-based printing inks, paints, etc. have been rapidly developed due to social needs such as environmental problems and resource saving. Similar to the oil-based printing ink and the oil-based paint, the required qualities of the water-based printing ink and the water-based paint are the adhesiveness to the printing medium, printability, density, gloss, viscosity and the like. Water-based printing inks and the like have hitherto been produced by drying, mixing and milling a crushed pigment and an aqueous resin in a disperser filled with glass beads or steel beads. Further, a method of producing a water-based printing ink by adding a resin and water to a wet cake of a pigment and dispersing the resin and water with a disperser is also used. However, the method using a dry pigment has a problem that the pigment agglomerated by drying is redispersed with a large amount of energy, so that the efficiency is poor and the levels of color development, density, gloss, etc. are low.

Further, the method of using a wet cake of pigments is usually
There is a problem in that the pigment content in the wet cake is low and the pigment content in the final ink is low, so the concentration of the printing ink is low and it cannot be a practical ink. In the method using the above-mentioned pigment wet cake, JP-A-57-53568 and JP-A-59-191765 disclose that a part of the water content in the pigment wet cake is increased in order to increase the pigment content in the pigment wet cake. Attempts have been made to solve the problem of pigment content by removing the so-called high-concentration wet. However, with the high-conc wet method, it is difficult to avoid aggregation of the pigment due to partial drying, and a fundamental solution has not been reached.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems associated with dry aggregation of pigments in the production of an aqueous coating composition from conventional dry pigments and wet cakes of pigments. It is an object of the present invention to provide an aqueous coating composition having excellent properties.

[0005]

The present inventors have completed the present invention as a result of intensive studies to solve the above-mentioned problems. That is, in the present invention, an aqueous dispersion of anionic crosslinked resin particles is added and mixed in an alkaline solution of a coupler component of an azo pigment, and a resin and a pigment are coprecipitated simultaneously with the formation of pigment particles by a coupling reaction with a diazo component. The present invention relates to a method for producing an aqueous coating composition, which comprises filtering and washing with water and redispersing the obtained pigment / resin mixed precipitate in an aqueous medium together with a base.

According to the present invention, pigment fine particles immediately after production,
That is, by adsorbing the pigment and the resin as they are as the primary particles of the pigment, it is possible to prevent the pigments from aggregating with each other, and thus it is possible to obtain an aqueous coating composition excellent in color development, density, gloss and the like.

The aqueous dispersion of anionic crosslinked resin particles used in the present invention can be applied to any resin type and manufacturing method, and is not particularly limited. But to give an example, first of all,
There is a graft copolymer of an aqueous resin having a carboxyl group and an ethylenically unsaturated monomer. There may be various methods for obtaining an aqueous dispersion of crosslinked resin particles with this type of resin system, but they can be obtained, for example, as follows.

That is, an aqueous resin having a carboxyl group is used as a dispersion stabilizer of a vinyl monomer, and an unsaturated glycidyl compound is used as a medium for a grafting reaction in an emulsion polymerization method of a polymerizable vinyl monomer. One of the aqueous dispersions of anionic crosslinked resin particles can be obtained by grafting a vinyl polymer onto the resin. In this case, the unsaturated glycidyl compound may be reacted with an aqueous resin having a carboxyl group prior to emulsion polymerization, or may be added together with another polymerizable vinyl monomer used in emulsion polymerization. The degree of cross-linking of the resin particles depends on the amount of the unsaturated glycidyl compound used, and when a higher degree of cross-linking is required, a polyfunctional monomer may be used as a part of the polymerizable vinyl monomer. it can.

The aqueous resin having a carboxyl group as used herein is not particularly limited, and conventionally known and commonly used various types of resins having an acid value of 20 to 250 are applied. Among these resins, if only representative ones are exemplified, polyester resin, polyamide resin, polyurethane resin, shellac or modified shellac, rosin derivative, acrylic resin and the like can be mentioned. Acrylic resins are taken up in detail as one of the preferable ones.

The above-mentioned acrylic resin means an ethylenically unsaturated monomer such as acrylic acid, methacrylic acid, maleic acid or itaconic acid, an acrylic acid ester, a methacrylic acid ester, and, if desired, a combination thereof. It refers to a copolymer with a vinyl monomer such as styrene, methyl styrene, or vinyl acetate, which has a polymerizability. The appropriate ratio of the acid component in the monomer composition depends on the amount of the unsaturated glycidyl compound used in the next step and the like, but is generally 5
Is selected from the range of up to 25%.

The amount of the unsaturated glycidyl compound used as a medium for grafting needs to be 0.05 to 0.5 equivalents relative to 1 equivalent of the carboxyl groups of the acrylic resin. If the amount is less than this range, the degree of cross-linking of the resin particles obtained by emulsion polymerization is insufficient, and redispersion after precipitation with an acid becomes difficult, and when using an amount above this range, a dispersion stabilizer. As a result, the resulting aqueous composition becomes unstable, and there is a risk that the entire system will gel during the polymerization.

As the above unsaturated glycidyl compound, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, methallyl glycidyl ether,
Examples thereof include vinyl glycidyl ether, butadiene monooxide, vinyl cyclohexene monoxide and the like.

A catalyst is usually required for the reaction between the carboxyl group of the acrylic resin and the glycidyl compound, and particularly preferable catalysts include dimethylaminoethanol and diethylaminoethanol. Since these are also used as they are as a base for neutralizing the carboxyl group, they can be added in a large amount and the reaction can be carried out more easily.

As described above, a water-soluble alkali salt of an acrylic resin is used as a dispersion stabilizer of a vinyl monomer, and the polymerizable vinyl monomer is emulsion-polymerized. The polymerizable vinyl monomer other than the unsaturated glycidyl compound is used. Examples of the monomer include acrylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate or 2-ethylhexyl acrylate; methacrylic acid esters such as methyl methacrylate, ethyl methacrylate and butyl methacrylate; maleic acid. Unsaturated dicarboxylic acid diesters such as diethyl, dibutyl fumarate or diethyl itaconic acid; vinyl esters such as vinyl acetate, vinyl propionate or vinyl tertiary carboxylate; styrene, α-methylstyrene, chlorostyrene, p- tert-butyl styrene or vinyl Aromatic vinyl compounds such as toluene; α-olefins such as ethylene or propylene; Dienes such as butadiene; Acrylonitrile, acrolein, vinyl methyl ketone, vinyl ethyl ketone, vinyl butyl ketone, diacetone acrylate or acetonitrile acrylate There are α, β-ethylenically unsaturated monomers, and in order to further increase the degree of crosslinking, diallylphthalate, divinylbenzene,
A monomer having two or more unsaturated bonds in one molecule such as allyl acrylate, 1,4-butanediol diacrylate and trimethylolpropane trimethacrylate can also be used.

When using the various typical polymerizable vinyl monomers as listed above, the ratio of the above acrylic resin to the water-soluble alkali salt is unsaturated in terms of solid content. A suitable range is 10 to 500 parts by weight, preferably 25 to 300 parts by weight of the water-soluble alkali salt of an acrylic resin, relative to 100 parts by weight of the monomers. When it deviates from this range, the polymerization stability is inevitably deteriorated, which is not preferable in any case.

On the other hand, as the radical polymerization initiator used in the copolymerization reaction, only typical ones are exemplified, and potassium persulfate, ammonium persulfate, azobisbutyronitrile or its hydrochloride, etc. Furthermore, cumene hydroperoxide or te
Organic peroxides such as rt-butyl hydroperoxide can also be used if necessary.

Further, these persulfates and peroxides are used in combination with a metal ion such as iron ion or a reducing agent such as sodium sulfoxylate formaldehyde, sodium pyrosulfite or L-ascorbic acid. So-called redox initiators can also be used.

From the practical point of view, the concentration of the aqueous resin dispersion during the copolymerization reaction should be such that the final solid content is 25 to 65% by weight.
The unsaturated monomers and radical polymerization initiator to the reaction system are
It goes without saying that any known method such as a batch charging method, a continuous dropping method or a divided addition method may be used. The reaction temperature at the time of the copolymerization reaction may also be in the range as in known emulsion polymerization reactions, for example, in the range of 50 to 80 ° C., and the copolymerization reaction may be carried out under normal pressure.
Alternatively, the gaseous unsaturated monomers are carried out under pressure.

As another example of an aqueous dispersion of anionic crosslinked resin particles in which the present invention can be effectively used, a urethane resin having a carboxyl group and an isocyanate group or a mixture thereof with another polyisocyanate compound is used as active hydrogen. Examples thereof include an aqueous dispersion of crosslinked polyurethane / urea resin particles obtained by neutralizing with a base having no atom, dispersing in an aqueous medium, and then reacting with a polyamine.

As a method for producing an aqueous dispersion of the crosslinked polyurethane / urea resin particles, the following method can be mentioned. A self-water-dispersible urethane polymer having an isocyanate group as a terminal group and a carboxyl group in the molecule is blended with a hydrophobic polyisocyanate prepolymer, if necessary, and then the self-water-dispersible urethane polymer or blend ( Or water) together with a base sufficient to neutralize the carboxyl groups into gradually stirring water (or a self-water-dispersible urethane polymer or blend) and then polyamine. Finally, if necessary, the solvent mixed in in the previous mixing step is distilled off under reduced pressure. Through the above steps, a stable aqueous dispersion of crosslinked polyurethane resin particles can be obtained.

The approximate molecular weight (number average molecular weight) of the above-mentioned self-water-dispersible urethane polymer is 2,0.
00 to 100,000, preferably 3,000 to
Those in the range of 30,000 are suitable, and
The self-dispersing urethane-based polymer is dissolved in an organic solvent and used in the form of a diluted solution.

The self-water-dispersible urethane-based polymer having such properties is not specially new, and is variously produced under the name of dispersion type resin, and is used in inks, paints, fiber processing agents or adhesives. It may be the one that is used for the purpose.

For example, an organic diisocyanate and a polyol component are reacted in an excess of isocyanate groups to obtain a urethane prepolymer having an isocyanate group at a terminal, and a low molecular weight having two or more active hydrogen atoms if necessary. A general method for producing a polyurethane in which a chain is extended with a chain extender composed of a compound can be applied. Here, in order to impart self-water dispersibility, a polyol component and / or
Alternatively, as at least a part of the chain extender, a compound having a hydrophilic group and two functional groups reactive with isocyanate at the end is used.

Specific examples of the above-mentioned organic diisocyanate include, but are not limited to, only representative examples, such as ethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate and lysine diisocyanate. Group diisocyanates, isophorone diisocyanates, hydrogenated 4,
Of alicyclic diisocyanates such as 4'-diphenylmethane diisocyanate, methylcyclohexylene diisocyanate, isopropylidene dicyclohexyl-4,4'-diisocyanate or 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, tolylene diisocyanate Such aromatic diisocyanates and the like can be mentioned.

As the above-mentioned polyol component, those generally used or capable of being used in the production of polyurethane can be applied here. Particularly representative examples are polyester polyols such as dicarboxylic acids (adipic acid, azelaic acid, sebacic acid, succinic acid, glutaric acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, etc.). And glycol (ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, 1,8-octamethylenediol, neopentyl glycol, bishydroxymethylcyclohexane, bishydroxyethylbenzene , An alkyl dialkanol amine, etc.), such as polyethylene adipate, polybutylene adipate, polyhexamethylene adipate, polyethylene / propylene adipate; ring-opening polymerization of lactones. Polylactone diols such as polycaprolactone diol,
Polyvalerolactone diol and the like and polyether polyol, for example, alkylene oxide (C2-4 alkylene oxide such as ethylene oxide, propylene oxide and butylene oxide) of low molecular weight glycol (ethylene glycol, propylene glycol, 1,4-butanediol, etc.). Etc.) and ring-opening polymerization products of the above alkylene oxides, specifically polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol and mixtures of two or more thereof. The molecular weight of these diol components is 500
~ 2,000 is suitable.

Further, only specific examples of the above-mentioned active hydrogen atom-containing low molecular weight compound used as a chain extender will be exemplified, and ethylene glycol, propylene glycol, 1,4-butanediol, 1,6 −
Low molecular weight glycols such as hexanediol and aliphatic diamines such as ethylenediamine, propylenediamine, butylenediamine, hexamethienediamine, 2,2,4-trimethylhexamethylenediamine and isophoronediamine, dicyclohexylmethane-4,4'-diamine, Examples are alicyclic diamines such as isopropylidenedicyclohexyl-4,4'-diamine and 1,4-diaminocyclohexane.

As the compound having a hydrophilic group and two functional groups reactive with isocyanate at the terminal, a polyether group, a phosphoric acid ester group, a sulfonic acid group and a tertiary amino group can be used as the hydrophilic group. Suitable are diols and diamines having any of groups, carboxyl groups, or neutralizing bases thereof. To give only representative examples as specific examples, polyoxyethylene glycol,
Polyoxyethylene diaminopropyl ether, trimethylolpropane monophosphate ester, trimethylolpropane monosulfate ester, polyester diol in which at least part of the dibasic acid component is sodium sulfosuccinic acid, or sodium sulfoisophthalic acid, N-methyldiethanolamine, Diaminocarboxylic acids such as lysine, cystine and 3,5-diaminocarboxylic acid,
There are 2,6-dihydroxybenzoic acid and especially dihydroxyalkanoic acids such as 2,2-dihydroxypropionic acid and polycaprolactone diol containing a carboxyl group obtained by the reaction of 2,2-dihydroxypropionic acid with ε-caprolactone.

When a necessary amount of these hydrophilic groups is introduced into the molecule of the urethane polymer, they are dispersed as fine particles in water, and the necessary amount is
It depends on the type of hydrophilic groups and their combinations. Particularly preferred as such a hydrophilic group is an acid value of 5 to 40 based on a carboxyl group and / or a sulfonic acid group.
And an acid containing an alkali metal salt thereof and a polyoxyethylene chain of 0 to 20%.

Next, the hydrophobic polyisocyanate prepolymer refers to those having a relatively low molecular weight having two or more isocyanate groups in the molecule, which cannot be dissolved or dispersed alone in water. . To exemplify particularly representative ones of those, there are various polyisocyanate prepolymers, which are generally called by the name of moisture-curable urethane resin, such as trimethylolpropane and ethylene. Polyols such as glycols, polyol prepolymers such as polyether polyols or polyester polyols, diisocyanates such as toluene diisocyanate, 1,6-hexane diisocyanate or isophorone diisocyanate are used as basic raw materials, and -OHe
It is obtained by a urethanization reaction under the condition of q / -NCOeq <1, and usually has a number average molecular weight of about 2,000 to 6,000.
The range of 0 is suitable, and the average number of functional groups is about 2 to 4.

In addition to these, various polyisocyanate prepolymers, which are generally called by the name of a curing agent for a two-pack type urethane coating material, may be mentioned.
Polymers of diisocyanates such as toluene diisocyanate, 1,6-hexane diisocyanate or isophorone diisocyanate; or adducts with polyols such as trimethylolpropane and ethylene glycol; or modified alohanate having water molecules intervening in the reaction The number average molecular weight is appropriately in the range of 600 to 1,000, and the average number of functional groups is appropriately in the range of 2 to 6.

The mixing ratio of the self-water-dispersible urethane polymer and the hydrophobic polyisocyanate prepolymer is:
The weight% of the hydrophobic polyisocyanate prepolymer with respect to the total weight of both is 0 ≦ weight% ≦ 20, preferably,
The range of 0 ≦% by weight ≦ 10 is suitable.

In the production of the above aqueous dispersion of crosslinked polyurethane / urea resin particles, a self-water-dispersible urethane polymer having an isocyanate group (3,000 to
Those having a number average molecular weight of 5,000 and an average number of functional groups of 2 or more are preferable. ) Is used as the hydrophobic polyisocyanate prepolymer, a crosslinked polyurethane produced by preparing and using a resin having a large number of average functional groups and a small number average molecular weight, and changing the mixing ratio of the two. It goes without saying that it is possible to change the average molecular weight between crosslinks in the resin particles broadly and very easily. It can be further changed by the difference in the number of functional groups of the polyamine.

As the base for neutralizing the carboxyl group contained in the self-water-dispersible urethane polymer, one that can avoid reaction with a free isocyanate group is used. Specific examples include trimethylamine, triethylamine, tributylamine, dimethylbenzylamine, lithium hydroxide, potassium hydroxide and sodium hydroxide.

Typical examples of polyamines used in the step of forming crosslinked particles include hydrazine, ethylenediamine, diethylenetriamine, triethylenetetramine and tetraethylenepentamine. Basically, a polyamine having water solubility and having a functionality of two or more in the reaction with isocyanate may be used. When the polyamine is added to the water-based dispersion system of the urethane polymer having an isocyanate group, it needs to be quickly performed to avoid the reaction between the isocyanate group and water. Normally, the reaction between isocyanate groups and water is slow,
On the other hand, the reaction between the isocyanate group and the polyamine is extremely fast and occurs almost instantaneously, so that the desired cross-linking reaction can be achieved without trouble by stirring at room temperature.

Here, the anionic non-crosslinked aqueous resin may be added together with the aqueous dispersion of the anionic crosslinked resin particles within a range that does not hinder the steps such as acid precipitation, filtration, water washing and redispersion. . As the azo pigment used in the present invention, an azo pigment generally used for printing inks, paints and the like can be used.

That is, examples of the azo pigments include disazo yellow pigments, azo lake pigments, insoluble azo pigments and condensed azo pigments. The amount of resin added to the coupler of the azo pigment is determined by the amount of resin required for the suitability of the intended aqueous coating composition, and is not a factor for producing the aqueous coating composition.

As typical examples of the acid used for acid precipitation, inorganic acids such as hydrochloric acid and sulfuric acid and organic acids such as formic acid and acetic acid can be used. Usually, it is appropriate to use hydrochloric acid or sulfuric acid. The amount of acid used is p
It is desirable that the amount of H be 5 or less.

The pigment / resin mixed precipitate obtained by acid precipitation is filtered with a filter press, a centrifuge or the like,
Wash and dehydrate. As a result, the unreacted raw materials contained in the pigment slurry, the debris of the polymerization catalyst contained in the aqueous dispersion of the inorganic material and the resin particles, the water-soluble substance such as the emulsifier or the salt produced by the acid precipitation are removed. The dehydrated pigment / resin mixed wet cake is redispersed in an aqueous medium containing a base. In this case, it is not necessary to dry and pulverize the pigment / resin mixed wet cake, and a wet cake containing water may be used.

The base used for redispersion in the aqueous medium can be arbitrarily selected from inorganic bases and organic bases. However, one of the objects of the present invention is to use an aqueous dispersion of crosslinked resin particles as a coating agent,
The purpose is to reduce the amount of base remaining in the film as much as possible to improve odor and hot water resistance.To that end, it is used as a neutralizing agent for crosslinked resin particle aqueous dispersions due to synthetic restrictions. Optimally, the various bases that were forced to be replaced by the more preferred bases such as ammonia by the method of the present invention.

The above aqueous medium refers to a system containing water or water and a water-miscible organic solvent. Typical examples of suitable water-miscible organic solvents include alcohols such as methanol, ethanol, isopropanol, normal propanol and tertiary butanol; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol. Examples thereof include glycol ethers such as monomethyl ether.

The method of redispersing the pigment / resin mixed wet cake in the aqueous medium can be carried out by using a stirrer and a disperser which is usually used for producing inks, paints and the like. . The thus-obtained aqueous dispersion of pigment-containing crosslinked resin particles is suitable as an aqueous coating composition for paints, inks and the like, and is excellent in various aptitudes such as color development, density and gloss.

[0042]

The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited thereto. In the following, all parts and% are based on weight unless otherwise specified.

Example 1 Preparation Example of Anionic Crosslinked Resin Particles Aqueous Dispersion (A-1) A four-necked flask equipped with a stirrer, a thermometer, a dropping funnel and a nitrogen gas inlet was charged with 100 parts of isopropyl alcohol. Charge and start stirring, raise the temperature to 80 ° C in a nitrogen stream,
The monomer mixture prepared in advance with 8 parts of acrylic acid, 70 parts of methyl methacrylate, 22 parts of butyl acrylate and 4 parts of azobisisobutyronitrile was added dropwise over 3 hours. The reaction temperature at this time is 80 ℃ ± 3 ℃
Held.

After the completion of dropping, the temperature was kept in the same temperature range for 2 hours, and then 0.2 part of azobisisobutyronitrile was added,
It was kept for another 2 hours, and the reaction was continued under stirring. After completion of the reaction, the mixture was cooled to 40 ° C., 9.9 parts of dimethylethanolamine was added, and then 330 parts of ion-exchanged water was added to make it water-soluble. Then, the transparent reaction product thus obtained is distilled under reduced pressure at 60 ° C. to remove isopropyl alcohol and excess water,
A semitransparent acrylic resin aqueous solution having a nonvolatile content of 30.0% was obtained.

Then, into a four-necked flask equipped with a stirrer, a thermometer, a dropping funnel and a nitrogen gas inlet, 8.3 parts of ion-exchanged water and 177.7 parts of the above water-soluble acrylic resin solution were charged and stirring was started. Then, the temperature was raised to 70 ° C. in a nitrogen stream, and 0.1 part of a 0.75% copper (II) sulfate aqueous solution was added,
Further, a mixed solution prepared in advance using 26.7 parts of styrene, 18.4 parts of 2-ethylhexyl acrylate, 1.0 part of divinylbenzene and 0.6 part of glycidyl methacrylate and 5% sodium thiosulfate. Aqueous solution 3.
7 parts and 0.93 parts of 5% potassium persulfate solution were added dropwise over 3 hours. The reaction temperature at this time was maintained at 70 ° C ± 3 ° C.

After completion of the dropping, the reaction was continued under stirring while maintaining the same temperature range for 1 hour. Nonvolatile matter 39.
At 7%, an aqueous resin dispersion having a viscosity of 540 cps and a pH of 8.3 was obtained. A small sample of this was insoluble in a large amount of tetrahydrofuran, indicating that the resin particles were crosslinked. This is designated as an anionic crosslinked resin particle aqueous dispersion (A-1).

Production Example of Aqueous Coating Composition A 0.5 L beaker was charged with 200 parts of water, 5.9 parts of 25% caustic soda and orthotoluidide acetoacetate (hereinafter referred to as AAO).
2.9 parts (abbreviated as T) and 3.5 parts acetoacetic acid meta-xylidide (hereinafter abbreviated as AAMX) were weighed and stirred at room temperature to dissolve AAOT and AAMX (this solution is referred to as a coupler solution). 15.1 parts of the above anionic crosslinked resin particle aqueous dispersion (A-1) was added to and mixed with this coupler liquid. Next, O. 5L beaker, water 50 parts, 20%
After 7.1 parts of hydrochloric acid and 3.8 parts of dichlorobenzidine hydrochloride were weighed and dispersed by stirring, an appropriate amount of ice was charged so that the temperature became 0 ° C., and then 5.4 parts of 40% sodium nitrite was added dropwise to form tetrazos. The liquid is called tetrazo liquid). Next, add 100 parts of water to a 1L beaker,
When the above-mentioned anionic crosslinked resin particle aqueous dispersion (A-1) mixed coupler solution and tetrazo solution were simultaneously added dropwise over 3 hours, a disazo yellow pigment (CI Pigmen) was obtained.
A mixture of t Yellow 136) / resin was precipitated. During the dropping of the coupler liquid and the tetrazo liquid, the dropping amounts were adjusted so that both components would be equimolar, and the reaction liquid temperature was adjusted to 10
The pH was kept at 4 ° C to 5 ° C below (adjusted appropriately with 5% hydrochloric acid or 5% caustic soda to keep the pH constant).

Next, in order to complete the precipitation of the resin, 5% hydrochloric acid was gradually added to this pigment / resin mixed slurry to adjust the pH to 4 or less. The precipitate was filtered and washed with water to obtain 50 parts of a pigment / resin mixed wet cake consisting of 10 parts of pigment, 6 parts of resin and 34 parts of water.

Next, 10 parts of isopropyl alcohol and 0.4 part of 28% ammonia water were added to 50 parts of the above pigment / resin mixed wet cake, and the mixture was stirred with a homodisper stirrer to re-disperse the precipitated resin, resulting in aqueous printing. Ink could be obtained. Table 1 shows the evaluation results of this water-based printing ink.

(Comparative Example 1) As described above, dimethylethanolamine in the anionic crosslinked resin particle aqueous dispersion (A-1) was generally replaced with ammonia due to the odor of the base remaining in the film. The dried resin is used to disperse the dry ground pigment to obtain an aqueous coating composition. The same applies hereinafter.

Preparation Example of Aqueous Dispersion of Crosslinked Resin Particles (B-1) 800 parts of ion-exchanged water and 14 parts of 35% hydrochloric acid aqueous solution were placed in a 2 L beaker to prepare an aqueous solution of anionic crosslinked resin particles obtained in Example 1. 500 parts of Dispersion (A-1) was gradually added with stirring to precipitate a resin. Next, the precipitated resin was filtered using a filter cloth, the residue was washed with water, and dehydrated with a centrifuge. A snow-like vegetable resin having a water content of 52% was obtained. This was transferred to a 1 L beaker, 70 parts of isopropyl alcohol and water were added, ion-exchanged water was added so that the total amount was 540 parts, and 28% ammonia water 6.4 was added.
Parts were added and stirred to re-disperse the resin. Nonvolatile content 3
6.2%, viscosity 250 cps and pH 8.2
An aqueous dispersion of crosslinked resin particles was obtained. This (B-1)
And

Production Example of Aqueous Coating Composition In a 0.5 L beaker, 200 parts of water, 5.9 parts of 25% caustic soda, 2.9 parts of AAOT and 3.5 parts of AAMX were weighed and stirred at room temperature to prepare AAOT and AAMX. It melt | dissolved and produced the coupler liquid. Next, O. In a 5 L beaker, 50 parts of water, 7.1 parts of 20% hydrochloric acid and 3.8 parts of dichlorobenzidine hydrochloride were weighed and dispersed by stirring, and then an appropriate amount of ice was charged to 0 ° C., and then 40% sodium nitrite was added. 4 parts was added dropwise to prepare a tetrazo solution. Next, in a 1L beaker,
When 100 parts of water was charged and the above coupler liquid and tetrazo liquid were simultaneously added dropwise to this 1 L beaker over 3 hours, a yellow pigment slurry was obtained. During the dropping of the coupler liquid and the tetrazo liquid, the dropping amounts were adjusted so that both components would be equimolar, and the reaction liquid temperature was maintained at 10 ° C or lower and pH = 5 to 6 (in order to keep the pH constant, Adjusted appropriately with 5% hydrochloric acid or 5% caustic soda). The resulting yellow pigment slurry was filtered, washed with water, dried, and then pulverized to obtain a powdery disazo yellow pigment (CI Pigment Yellow 1).
36) 10 parts were obtained. To 10 parts of this powdery disazo yellow pigment, 1 part of the aqueous dispersion of crosslinked resin particles (B-1) was added.
6.6 parts, isopropyl alcohol 7.9 parts, water 25.
9 parts (water has the same pigment% as in Example 1, so the same applies to the following Comparative Examples) and 3 mmφ glass beads 200
Parts were added and dispersed with a paint conditioner for 60 minutes to obtain an aqueous printing ink. Table 1 shows the evaluation results of this water-based printing ink.

Example 2 Production Example of Aqueous Coating Composition A 1 L beaker was charged with 140 parts of water and 9.0% of 25% caustic soda.
Parts and 4.4 parts of 2-hydroxynaphthalene-3-carbamide were weighed and dissolved under stirring at room temperature (this solution is referred to as a coupler solution). 15.1 parts of the above anionic crosslinked resin particle aqueous dispersion (A-1) was added to and mixed with this coupler liquid. Next, in a 0.5L beaker, 80 parts of water, 20%
Hydrochloric acid 12.6 parts and 3-amino-4-methoxybenzanilide 5.6 parts were weighed, dissolved under stirring at room temperature, and then at 0 ° C.
Add an appropriate amount of ice to obtain 40% sodium nitrite 4.2
A portion was dropped to diazotize (this liquid is called diazo liquid).
Next, the above anionic crosslinked resin particle aqueous dispersion (A-1)
When the liquid temperature of the mixed coupler liquid was kept at 10 ° C. or lower and the diazo liquid was added dropwise over 15 minutes, the red pigment (C.I. Pig.
ment Red 213) / resin mixture was precipitated. The pH after the reaction was 5.0. Next, in order to complete the precipitation of the resin, 5% hydrochloric acid was gradually added to this pigment / resin mixed slurry to adjust the pH to 4 or less. The precipitate was filtered and washed with water to obtain 45.5 parts of a pigment / resin mixed wet cake consisting of 10 parts of pigment, 6 parts of resin and 29.5 parts of water. Next, the obtained pigment / resin mixed wet cake 4
When 10 parts of isopropyl alcohol and 0.4 parts of 28% ammonia water were added to 5.5 parts and stirred with a homodisper stirrer, the precipitated resin was redispersed and an aqueous printing ink could be obtained. The evaluation results of this water-based printing ink are shown in Table 1.
Shown in

Comparative Example 2 Production Example of Aqueous Coating Composition In a 1 L beaker, 140 parts of water and 25% caustic soda 9.0.
Parts and 4.4 parts of 2-hydroxynaphthalene-3-carbamide were weighed and dissolved under stirring at room temperature to prepare a coupler solution. Next, 80 parts of water, 12.6 parts of 20% hydrochloric acid and 5.6 parts of 3-amino-4-methoxybenzanilide were weighed in a 0.5 L beaker, dissolved under stirring at room temperature, and then adjusted to an appropriate amount of 0 ° C. Ice was added and 4.2 parts of 40% sodium nitrite was added dropwise to prepare a diazo solution. Next, the liquid temperature of the above coupler liquid was kept at 10 ° C. or lower, and the diazo liquid was added dropwise over 15 minutes to obtain a red pigment slurry. PH after reaction =
It was 5.0. The obtained red pigment slurry is filtered, washed, dried, and then pulverized to obtain powdered red pigment (C.I.P.
igment Red 213) 10 parts was obtained. To 10 parts of the powdered red pigment, 16.6 parts of anionic dispersion of anionic crosslinked resin particles (B-1), 7.9 parts of isopropyl alcohol, 21.4 parts of water and 3 mmφ glass beads 20.
0 parts was added and dispersed for 60 minutes with a paint conditioner to obtain an aqueous printing ink. Table 1 shows the evaluation results of this water-based printing ink.

Example 3 Preparation Example of Aqueous Dispersion of Anionic Crosslinked Resin Particles (A-2) PLACCEL 212 (manufactured by Daicel Chemical Industries, Ltd., polycaprolactone diol, hydroxyl value 9) was placed in a reaction vessel.
186.9 parts of 0 mg KOH / g, molecular weight 1250) and 100.0 parts of isophorone diisocyanate were charged. This was heated to 110 ° C. with stirring. After 1 hour, the mixture was cooled to 80 ° C., 20.1 parts of dimethylolpropionic acid, 0.3 parts of dibutyltin dilaurate and 76.8 parts of ethyl acetate were added, and the mixture was reacted at 80 ° C. for 2 hours. Here, 16.2 parts and ME of Bernock DN-980S (manufactured by Dainippon Ink and Chemicals, Inc., polyisocyanate obtained by burizing HDI, NCO content 20%)
408 parts of K were added. At this time, the NCO group content was 4.9% in terms of solid content. This was cooled to 30 ° C. or lower, 15.2 parts of triethylamine was added, and then 1293 parts of ion-exchanged water was added to obtain an O / W type emulsion. Then, diethylenetriamine 5% aqueous solution of 23
Gradually add 4 parts, and after the addition is complete, raise the temperature to 60 ° C and
Stirring was continued for 0 minutes. Then, distillation was performed under reduced pressure to remove a part of the solvent and water. This was a slightly opalescent translucent liquid, and when a small amount was placed in a test tube and tetrahydrofuran was added, it became turbid, and it was shown that it was crosslinked and became insoluble. Nonvolatile content 35.6%
And had a viscosity of 340 cps and a pH of 7.7. Hereinafter, this is an aqueous dispersion of anionic crosslinked resin particles (A-
2).

Production Example of Aqueous Coating Composition In a 0.5 L beaker, 200 parts of water, 5.9 parts of 25% caustic soda, 2.9 parts of AAOT and 3.5 parts of AAMX were weighed and stirred at room temperature to prepare AAOT and AAMX. It melt | dissolved and produced the coupler liquid. To this coupler liquid, 16.9 parts of the anionic crosslinked resin particle aqueous dispersion (A-2) was added and mixed. Next, O. In a 5L beaker, 50 parts of water, 2
7.1 parts of 0% hydrochloric acid and dichlorobenzidine hydrochloride 3.8
After weighing and agitating the parts, an appropriate amount of ice was charged so that the temperature became 0 ° C., and then 5.4 parts of 40% sodium nitrite was added dropwise to prepare a tetrazo solution. Next, 100 parts of water was charged into a 1L beaker, and the anionic crosslinked resin particle aqueous dispersion (A-2) mixed coupler solution and the tetrazo solution were simultaneously added dropwise to the 1L beaker over 3 hours, whereby disazo yellow was obtained. Pigment (C.I. Pigment Yellow 1
36) / resin mixture precipitated out. During the dropping of the coupler liquid and the tetrazo liquid, the dropping amounts were adjusted so that both components would be equimolar, and the reaction liquid temperature was 10 ° C. or lower, pH = 4 to 5
(5% hydrochloric acid or 5% to keep the pH constant)
% Adjusted appropriately with caustic soda). Next, in order to complete the resin precipitation, an additional 5% was added to this pigment / resin mixed slurry.
Hydrochloric acid was gradually added to adjust the pH to 4 or less. The precipitate was filtered and washed with water to obtain 43.5 parts of pigment / resin mixed wet cake consisting of 10 parts of pigment, 6 parts of resin and 27.5 parts of water.
Next, 10 parts of isopropyl alcohol and 0.4 part of 28% ammonia water were added to 43.5 parts of the above pigment / resin mixed wet cake, and the mixture was stirred with a homodisper stirrer.
The precipitated resin was redispersed and an aqueous printing ink could be obtained. Table 1 shows the evaluation results of this water-based printing ink.

Comparative Example 3 Preparation Example of Aqueous Dispersion of Anionic Cross-Linked Resin Particles (B-2) 500 parts of ion-exchanged water and 10 parts of 35% hydrochloric acid aqueous solution were put into a 2 L beaker, and obtained in Example 3. 500 parts of the anionic crosslinked resin particle aqueous dispersion (A-2) was gradually added with stirring to precipitate the resin. Next, the precipitated resin was filtered using a filter cloth, the residue was washed with water, and dehydrated with a centrifuge. A snow-like vegetable resin having a water content of 49% was obtained. This was transferred to a 1 L beaker, 83 parts of isopropyl alcohol and water were added, ion-exchanged water was added so that the total amount became 587 parts, and further 5.6 parts of 28% ammonia water was added and stirred, The resin was redispersed. Nonvolatile matter 30.
An anionic crosslinked resin particle aqueous dispersion having a viscosity of 370 cps and a pH of 8.6 was obtained at 0%. This is (B
-2).

Production Example of Aqueous Coating Composition Similar to “Production Example of Aqueous Coating Composition” of Comparative Example 1, AAOT
/ AAMX coupler solution and dichlorobenzidine tetrazo solution were subjected to a coupling reaction to obtain a yellow pigment slurry, which was filtered, washed with water, dried and then pulverized to obtain a powdery disazo yellow pigment (CI Pigment Yell).
ow 136) 10 parts were obtained. An aqueous dispersion of crosslinked resin particles (B-
2) 20 parts, isopropyl alcohol 7.2 parts, water 1
6.7 parts and 200 parts of 3 mmφ glass beads were added and dispersed for 60 minutes with a paint conditioner to obtain an aqueous printing ink. Table 1 shows the evaluation results of this water-based printing ink.

Example 4 Production Example of Aqueous Coating Composition In a 1 L beaker, 140 parts water, 25% caustic soda 9.0
Parts and 4.4 parts of 2-hydroxynaphthalene-3-carbamide were weighed and dissolved under stirring at room temperature to prepare a coupler solution. To this coupler liquid, 16.9 parts of the anionic crosslinked resin particle aqueous dispersion (A-2) was added and mixed. Next, in a 0.5 L beaker, 80 parts of water and 12.6 of 20% hydrochloric acid were added.
Parts and 3-amino-4-methoxybenzanilide 5.6
After weighing out parts and dissolving under stirring at room temperature, an appropriate amount of ice was added so as to reach 0 ° C., and 4.2 parts of 40% sodium nitrite was added dropwise to prepare a diazo solution. Next, the liquid temperature of the anionic crosslinked resin particle aqueous dispersion (A-2) mixed coupler liquid was maintained at 10 ° C. or lower, and the diazo liquid was added dropwise over 15 minutes to give a red pigment (CI Pigment Red 213). / The resin mixture was precipitated. The pH after the reaction was 5.0. Next, in order to complete the precipitation of the resin, 5% hydrochloric acid was gradually added to this pigment / resin mixed slurry, and the pH =
It was set to 4 or less. The precipitate was filtered and washed with water to obtain 35.7 parts of a pigment / resin mixed wet cake consisting of 10 parts of pigment, 6 parts of resin and 19.7 parts of water. Next, 10 parts of isopropyl alcohol and 0.4 part of 28% ammonia water were added to 35.7 parts of the obtained pigment / resin mixed wet cake, and the mixture was stirred with a homodisper stirrer to re-disperse the precipitated resin,
An aqueous printing ink could be obtained. Table 1 shows the evaluation results of this water-based printing ink.

Comparative Example 4 Production Example of Aqueous Coating Composition As in Comparative Example 2 “Production Example of Aqueous Coating Composition”, 2-hydroxynaphthalene-3-carbamide coupler solution and 3 were prepared.
The red pigment slurry obtained by the coupling reaction with a diazo solution of -amino-4-methoxybenzanilide was filtered, washed with water, dried, and then pulverized to obtain a powdered red pigment (C.
I. Pigment Red 213) (10 parts).
To 10 parts of this powdery red pigment, 20 parts of an anionic cross-linked resin particle aqueous dispersion (B-2), 7.2 parts of isopropyl alcohol, 8.9 parts of water and 3 mmφ glass beads 200.
Parts were added and dispersed with a paint conditioner for 60 minutes to obtain an aqueous printing ink. Table 1 shows the evaluation results of this water-based printing ink.

Example 5 Preparation Example of Aqueous Dispersion of Anionic Crosslinked Resin Particles (A-3) In a reaction vessel, PolyTHF 1000 (manufactured by BSF Japan Ltd., polytetramethylene glycol, hydroxyl value 112 mgKOH / g, Molecular weight 1000)
400 parts and 170 parts of isophorone diisocyanate were charged. This was heated to 110 ° C. with stirring. After 1 hour, the mixture was cooled to 80 ° C., 30 parts of dimethylolpropionic acid, 0.3 part of tin octylate and 150 parts of ethyl acetate were added, and the mixture was reacted at 80 ° C. for 2 hours. Here, 42.1 parts of Burnock DN-980 (manufactured by Dainippon Ink and Chemicals, Inc., polyisocyanate having HDI burette, NCO content 16%) and 260 of MEK are used.
Added parts. At this time, the NCO group content was 2.9% in terms of solid content. Cool it to less than 30 ° C, 2%
450 parts of an aqueous NaOH solution was added, and then 1655 parts of ion-exchanged water was added to obtain an O / W type emulsion.
Subsequently, 152 parts of a 10% aqueous solution of diethylenetriamine was gradually added, and after the addition was completed, the temperature was raised to 60 ° C. and stirring was continued for 30 minutes. Then, distillation was performed under reduced pressure to remove a part of the solvent and water. This was a slightly opalescent translucent liquid, and when a small amount was placed in a test tube and tetrahydrofuran was added, it became turbid, and it was shown that it was crosslinked and became insoluble. Nonvolatile content 22.0%, p
H was 7.7. Hereinafter, this is referred to as anionic crosslinked resin particle aqueous dispersion (A-3).

Production Example of Aqueous Coating Composition In a 0.5 L beaker, 200 parts of water, 5.9 parts of 25% caustic soda, 2.9 parts of AAOT and 3.5 parts of AAMX were weighed and stirred at room temperature to prepare AAOT and AAMX. It melt | dissolved and produced the coupler liquid. 27.3 parts of the above anionic crosslinked resin particle aqueous dispersion (A-3) was added to and mixed with this coupler liquid. Next, O. In a 5L beaker, 50 parts of water, 2
7.1 parts of 0% hydrochloric acid and dichlorobenzidine hydrochloride 3.8
After weighing and agitating the parts, an appropriate amount of ice was charged so that the temperature became 0 ° C., and then 5.4 parts of 40% sodium nitrite was added dropwise to prepare a tetrazo solution. Next, 100 parts of water was charged into a 1 L beaker, and the anionic crosslinked resin particle aqueous dispersion (A-3) mixed coupler solution and the tetrazo solution were simultaneously added dropwise to the 1 L beaker over 3 hours to obtain a disazo yellow. Pigment (C.I. Pigment Yellow 1
36) / resin mixture precipitated out. During the dropping of the coupler liquid and the tetrazo liquid, the dropping amounts were adjusted so that both components would be equimolar, and the reaction liquid temperature was 10 ° C. or lower, pH = 4 to 5
(5% hydrochloric acid or 5% to keep the pH constant)
% Adjusted appropriately with caustic soda). Next, in order to complete the resin precipitation, an additional 5% was added to this pigment / resin mixed slurry.
Hydrochloric acid was gradually added to adjust the pH to 4 or less. The precipitate was filtered and washed with water to obtain 40 parts of a pigment / resin mixed wet cake consisting of 10 parts of pigment, 6 parts of resin and 24 parts of water. Next, 10 parts of isopropyl alcohol and 0.4 part of 28% ammonia water were added to 40 parts of the above-mentioned pigment / resin mixed wet cake and stirred with a homodisper stirrer to re-disperse the precipitated resin to obtain an aqueous printing ink. I was able to. Table 1 shows the evaluation results of this water-based printing ink.

Comparative Example 5 Preparation Example of Anionic Crosslinked Resin Particle Aqueous Dispersion (B-3) Into a 2 L beaker, 800 parts of ion-exchanged water and 10 parts of 35% hydrochloric acid aqueous solution were placed, and obtained in Example 3. 910 parts of the anionic crosslinked resin particle aqueous dispersion (A-3) was gradually added with stirring to precipitate the resin. Next, the precipitated resin was filtered using a filter cloth, the residue was washed with water, and dehydrated with a centrifuge. A snow-like vegetable resin having a water content of 46% was obtained. This was transferred to a 1 L beaker, 85 parts of isopropyl alcohol and water were added, ion-exchanged water was added so that the total amount was 620 parts, and 28% ammonia water was added.
6 parts were added and stirred to disperse the resin. Nonvolatile content 3
2.0%, viscosity 370 cps, and pH 8.5
To obtain an aqueous dispersion of anionic crosslinked resin particles. This is designated as (B-3).

Production Example of Aqueous Coating Composition Similar to “Production Example of Aqueous Coating Composition” of Comparative Example 1, AAOT
/ AAMX coupler solution and dichlorobenzidine tetrazo solution were subjected to coupling reaction to obtain a yellow pigment slurry, which was filtered, washed with water, dried and then pulverized to obtain a powdery disazo yellow pigment (CI Pigment Yell).
ow 136) 10 parts were obtained. An aqueous dispersion of crosslinked resin particles (B-
3) 18.8 parts, isopropyl alcohol 7.4 parts,
14.2 parts of water and 200 parts of 3 mmφ glass beads were added and dispersed for 60 minutes with a paint conditioner to obtain an aqueous printing ink. Table 1 shows the evaluation results of this water-based printing ink.

Example 6 Production Example of Aqueous Coating Composition In 1 L beaker, 140 parts of water, 25% caustic soda 9.0
Parts and 4.4 parts of 2-hydroxynaphthalene-3-carbamide were weighed and dissolved under stirring at room temperature to prepare a coupler solution. 27.3 parts of the above anionic crosslinked resin particle aqueous dispersion (A-3) was added to and mixed with this coupler liquid. Next, in a 0.5 L beaker, 80 parts of water and 12.6 of 20% hydrochloric acid were added.
Parts and 3-amino-4-methoxybenzanilide 5.6
After weighing out parts and dissolving under stirring at room temperature, an appropriate amount of ice was added so as to reach 0 ° C., and 4.2 parts of 40% sodium nitrite was added dropwise to prepare a diazo solution. Next, the liquid temperature of the anionic crosslinked resin particle aqueous dispersion (A-3) mixed coupler liquid was maintained at 10 ° C. or lower, and the diazo liquid was added dropwise over 15 minutes to give a red pigment (CI Pigment Red 213). / The resin mixture was precipitated. The pH after the reaction was 5.0. Next, in order to complete the precipitation of the resin, 5% hydrochloric acid was gradually added to this pigment / resin mixed slurry, and the pH =
It was set to 4 or less. The precipitate was filtered and washed with water to obtain 33.3 parts of a pigment / resin mixed wet cake consisting of 10 parts of pigment, 6 parts of resin and 17.3 parts of water. Next, 10 parts of isopropyl alcohol and 0.4 parts of 28% ammonia water were added to 33.3 parts of the obtained pigment / resin mixed wet cake, and the mixture was stirred with a homodisper stirrer to re-disperse the precipitated resin,
An aqueous printing ink could be obtained. Table 1 shows the evaluation results of this water-based printing ink.

Comparative Example 6 Production Example of Aqueous Coating Composition As in Comparative Example 2 “Production Example of aqueous coating composition”, 2-hydroxynaphthalene-3-carbamide coupler solution and 3 were prepared.
The red pigment slurry obtained by the coupling reaction with a diazo solution of -amino-4-methoxybenzanilide was filtered, washed with water, dried, and then pulverized to obtain a powdered red pigment (C.
I. Pigment Red 213) (10 parts).
To 10 parts of this powdery red pigment, 18.8 parts of anionic dispersion of anionic crosslinked resin particles (B-3), 7.4 parts of isopropyl alcohol, 7.5 parts of water and 3 mmφ glass beads 20.
0 parts was added and dispersed for 60 minutes with a paint conditioner to obtain an aqueous printing ink. Table 1 shows the evaluation results of this water-based printing ink.

Example 7 Production Example of Aqueous Coating Composition 200 parts of water, 5.9 parts of 25% caustic soda, 2.9 parts of AAOT and 3.5 parts of AAMX were weighed in a 0.5 L beaker and stirred at room temperature. , AAOT and AAMX were dissolved to prepare a coupler solution. To this coupler liquid, 7.6 parts of the anionic crosslinked resin particle aqueous dispersion (A-1) and 8.4 parts of the anionic crosslinked resin particle aqueous dispersion (A-2) were added and mixed. Next, O. In a 5L beaker, 50 parts of water, 2
7.1 parts of 0% hydrochloric acid and dichlorobenzidine hydrochloride 3.8
After weighing and agitating the parts, an appropriate amount of ice was charged so that the temperature became 0 ° C., and then 5.4 parts of 40% sodium nitrite was added dropwise to prepare a tetrazo solution. Next, 100 parts of water was charged into a 1L beaker, and the anion-based crosslinked resin particle aqueous dispersion (A-1) / (A-2) mixed coupler solution and the tetrazo solution were added to this 1L beaker for 3 hours. When dropped at the same time,
Disazo Yellow Pigment (C.I. Pigment Ye
A mixture of low 136) / resin was precipitated. During the dropping of the coupler liquid and the tetrazo liquid, the dropping amounts were adjusted so that both components would be equimolar, and the reaction liquid temperature was 10 ° C. or lower.
The pH was kept at 4-5 (5% to keep the pH constant)
Adjusted accordingly with hydrochloric acid or 5% caustic soda). Next, in order to complete the precipitation of the resin, 5% hydrochloric acid was gradually added to this pigment / resin mixed slurry to adjust the pH to 4 or less. The precipitate was filtered and washed with water, and a pigment / resin mixed wet cake 4 comprising 10 parts of pigment, 6 parts of resin and 29.5 parts of water was used.
5.5 parts were obtained. Next, 45.5 parts of the above pigment / resin mixed wet cake was mixed with 10 parts of isopropyl alcohol and 28 parts of isopropyl alcohol.
When 0.4 part of aqueous ammonia was added and the mixture was stirred with a homodisper stirrer, the precipitated resin was redispersed and an aqueous printing ink could be obtained. Table 1 shows the evaluation results of this water-based printing ink.

Comparative Example 7 As in “Production Example of Aqueous Coating Composition” of Comparative Example 1, a yellow pigment slurry obtained by coupling reaction of a coupler solution of AAOT / AAMX and a tetrazo solution of dichlorobenzidine was filtered. After washing with water, drying and crushing, the powdery disazo yellow pigment (C.I.
Pigment Yellow 136) (10 parts). To 10 parts of the powdery disazo yellow pigment, 8.3 parts of the crosslinked resin particle aqueous dispersion (B-1), 10.0 parts of the crosslinked resin particle aqueous dispersion (B-2), 7.5 parts of isopropyl alcohol, Water (20.1 parts) and 3 mmφ glass beads (200 parts) were added and dispersed for 60 minutes with a paint conditioner to obtain an aqueous printing ink. Table 1 shows the evaluation results of this water-based printing ink.

Example 8 Production Example of Aqueous Coating Composition In a 1 L beaker, 140 parts of water, 25% caustic soda 9.0
Parts and 4.4 parts of 2-hydroxynaphthalene-3-carbamide were weighed and dissolved under stirring at room temperature to prepare a coupler solution. To this coupler liquid, 7.6 parts of the anionic crosslinked resin particle aqueous dispersion (A-1) and 8.4 parts of the anionic crosslinked resin particle aqueous dispersion (A-2) were added and mixed. Next, in a 0.5 L beaker, 80 parts of water and 12.6 of 20% hydrochloric acid were added.
Parts and 3-amino-4-methoxybenzanilide 5.6
After weighing out parts and dissolving under stirring at room temperature, an appropriate amount of ice was added so as to reach 0 ° C., and 4.2 parts of 40% sodium nitrite was added dropwise to prepare a diazo solution. Next, the diazo solution was added dropwise to the above anionic crosslinked resin particle aqueous dispersion (A-1) / (A-2) mixed coupler solution over 15 minutes to give a red pigment (C.I.
Pigment Red 213) / resin mixture precipitated out. The pH after the reaction was 5.0. Next, in order to complete the precipitation of the resin, 5% hydrochloric acid was gradually added to this pigment / resin mixed slurry to adjust the pH to 4 or less.
The precipitate is filtered and washed with water to obtain 10 parts of pigment, 6 parts of resin, 24 parts of water.
40 parts of pigment / resin mixed wet cake consisting of 10 parts were obtained. Next, the obtained pigment / resin mixed wet cake 40
When 10 parts of isopropyl alcohol and 0.4 parts of 28% ammonia water were added to the parts and stirred with a homodisper stirrer, the precipitated resin was redispersed and an aqueous printing ink could be obtained. Table 1 shows the evaluation results of this water-based printing ink.

Comparative Example 8 Production Example of Aqueous Coating Composition As in Comparative Example 2 “Production Example of Aqueous Coating Composition”, 2-hydroxynaphthalene-3-carbamide coupler solution and 3 were prepared.
The red pigment slurry obtained by the coupling reaction with a diazo solution of -amino-4-methoxybenzanilide was filtered, washed with water, dried, and then pulverized to obtain a powdered red pigment (C.
I. Pigment Red 213) (10 parts).
To 10 parts of this powdery red pigment, 8.3 parts of anionic crosslinked resin particle aqueous dispersion (B-1), 10.0 parts of anionic crosslinked resin particle aqueous dispersion (B-2), isopropyl alcohol 7.5 Parts, 14.6 parts of water and 200 parts of 3 mmφ glass beads were added and dispersed for 60 minutes with a paint conditioner to obtain an aqueous printing ink. Table 1 shows the evaluation results of this water-based printing ink.

(Results of Evaluation of Aqueous Printing Ink) Examples 1 to 1
8. The water-based printing inks of Comparative Examples 1 to 8 were applied to a transparent film using a drawdown rod # 6, and the 60-degree gloss of the coating film was measured. The results are shown in Table 1.

[0072]

[Table 1]

The measuring instruments used in the above evaluation are as follows. ,

[0074]

EFFECTS OF THE INVENTION The present invention can solve the problems associated with dry aggregation of pigments in the production of an aqueous coating composition by the conventional method, and by adsorbing the primary particles of the pigment immediately after formation and the resin to the primary pigment It is possible to prevent the particles from aggregating with each other and to produce an aqueous coating composition excellent in color development, density, gloss and the like. Further, in the present invention, since the dry pulverization process is not performed, the working environment associated with dust can be improved and energy can be saved.

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Claims (10)

[Claims] 1. An aqueous dispersion of anionic crosslinked resin particles is added and mixed into a coupler component of an azo pigment, and a resin and a pigment are coprecipitated at the same time when the pigment particles are formed by a coupling reaction with a diazo component. A method for producing an aqueous coating composition containing an azo pigment, which comprises filtering and washing with water, and re-dispersing the obtained pigment / resin mixed precipitate together with a base in an aqueous medium. 2. The method for producing an aqueous coating composition according to claim 1, wherein the base used during redispersion is ammonia. 3. The method for producing an aqueous coating composition according to claim 1, wherein the aqueous dispersion of anionic crosslinked resin particles is a graft copolymer of an aqueous resin having a carboxyl group and an ethylenically unsaturated monomer. . 4. The aqueous dispersion of anionic crosslinked resin particles comprises a polyurethane urea resin.
A method for producing the aqueous coating composition described. 5. An aqueous dispersion of anionic crosslinked resin particles comprising a polyurethaneurea resin, wherein an urethane resin having a carboxyl group and an isocyanate group or a mixture thereof with another polyisocyanate compound is treated with a base having no active hydrogen atom. The method for producing an aqueous coating composition according to claim 4, which is obtained by neutralizing, dispersing in an aqueous medium, and then reacting with a polyamine. 6. The method for producing an aqueous coating composition according to claim 4, wherein the diol component of the polyurethane resin is a polyether diol or polyester diol having a molecular weight of 500 to 2,000. 7. The method for producing an aqueous coating composition according to claim 4, wherein the diol component of the polyurethane resin is dimethylolpropionic acid. 8. The diisocyanate component of the polyurethane resin is isophorone diisocyanate.
A method for producing the aqueous coating composition according to item 1. 9. The polyurethane urea resin chain extender is polyoxyethylene diamino ether.
A method for producing the aqueous coating composition according to item 1. 10. The method for producing an aqueous coating composition according to claim 4, wherein diethylenetriamine is used as the polyamine.