JPH10140065A - Aqueous recording liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous recording liquid which has good re-dissolving property, prevents non-ejection due to drying of a recording liquid at a nozzle tip, and can realize stable ejection particularly in a thermal type ink jet printer system. To do. SOLUTION: (1) An anionic compound obtained by coating an organic pigment or carbon black with an organic polymer compound containing an anionic group neutralized with a base, for example, an acrylic resin having a neutralized carboxyl group. An aqueous recording liquid containing a microencapsulated pigment and (2) a water-soluble anionic surfactant and / or a nonionic surfactant having an HLB value of 14 or more, wherein an organic compound in the anionic microencapsulated pigment is used. An aqueous recording liquid having a pigment or carbon black content of 35 to 80% by weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an aqueous ballpoint pen,
The present invention relates to a recording liquid useful for writing instruments such as fountain pens, water-based felt pens, and water-based markers, and on-demand type ink jet printers such as a thermal method and a piezo method such as a bubble jet.

[0002]

2. Description of the Related Art Conventionally, dyes have been used in recording liquids requiring high definition. A recording liquid using a dye has characteristics such as high transparency, high definition, and excellent color rendering properties, but has problems such as light resistance and water resistance.

In recent years, in order to solve the problems of light fastness and water fastness, replacement of dyes with pigments has been studied. Further, from the viewpoints of dispersion stability and storage stability of the pigment in the recording liquid and light resistance of the dye, a recording liquid containing a microencapsulated dye or pigment has been studied.

As a method of using microcapsules in a recording liquid for an ink jet printer, for example, Japanese Patent Application Laid-Open No. 62-95366 discloses a method in which microcapsules in which a dye ink is encapsulated in polymer particles are used as the recording liquid. JP-A-1-170672 discloses a method in which a dye is dissolved or dispersed in a solvent substantially insoluble in water, and this is emulsified and dispersed in water using a surfactant to obtain a microencapsulated dye by a conventional method. The method used for the recording liquid is disclosed in JP-A-5-39447, in which a microcapsule having an inclusion in which a sublimable disperse dye is dissolved or dispersed in at least one of water, a water-soluble solvent and at least one polyester resin is recorded. Japanese Patent Application Laid-Open No. 6-313141 discloses an aqueous ink composition comprising colored emulsion polymer particles and various aqueous materials. There has been disclosed.

[0005] However, although the water resistance and light resistance, the storage stability of the recording liquid, and the like are improved by the above-described technique, after printing with an ink jet printer, the ink jet printer is left as it is for a long period of time to print again. In this case, the recording liquid re-dissolves poorly and the recording liquid dries at the nozzle tip,
There has been a problem that the recording liquid is not ejected.

In recent years, with the increase in printing speed, when a recording liquid containing microcapsules is used, especially in a thermal type ink jet printer system, non-discharge of the recording liquid (liquid exhaustion) occurs in high-speed continuous printing. ) Has arisen.

[0007]

The problem to be solved by the present invention is that it has good re-dissolvability and prevents non-discharge due to drying of the recording liquid at the nozzle tip, and is particularly stable in a thermal type ink jet printer system. An object of the present invention is to provide an aqueous recording liquid capable of realizing a proper ejection.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have found that (1) a pigment may be added together with a curing agent and a polymer compound, if necessary, to a base. (2) using an anionic microencapsulated pigment coated with an organic polymer compound containing an anionic group neutralized with (hereinafter, abbreviated as "anionic organic polymer compound"); An aqueous recording liquid containing a water-soluble anionic surfactant and / or a nonionic surfactant having an HLB value of 14 or more, wherein the content of an organic pigment or carbon black in an anionic microencapsulated pigment Is 35 to 80% by weight, the aqueous recording liquid has high storage stability and reliability after being left for a long period of time, does not impair re-dissolvability, and uses a thermal type ink jet printer. Also in the high-speed printing, it found such to obtain a stable recording image without non-ejection occurs, thereby completing the present invention.

That is, the present invention provides: (1) an anionic microencapsulated pigment obtained by coating an organic pigment or carbon black with an organic polymer compound having an anionic group neutralized with a base; and (2) a water-soluble anionic surfactant And / or HLB
Aqueous recording liquid containing a nonionic surfactant having a valence of 14 or more, wherein the content of the organic pigment or carbon black in the anionic microencapsulated pigment is 35 to 80% by weight. Recording liquid,

[0010] 2. The aqueous recording liquid according to the above 1, wherein the organic polymer compound containing an anionic group neutralized with a base is an organic polymer compound containing a carboxyl group neutralized with a base,

3. 3. The aqueous recording liquid according to the above 2, wherein the water-soluble anionic surfactant and / or the nonionic surfactant having an HLB value of 14 or more is a sorbitan surfactant.

4. An organic polymer compound containing an anionic group neutralized with a base has an acid value of 30 to 150 KOH.
mg / g, the aqueous recording liquid according to the above 2 or 3, wherein the carboxyl group of the acrylic resin having a number average molecular weight of 2,000 to 20,000 is neutralized with a base.

5. Organic polymer compounds containing an anionic group neutralized with a base have a glass transition temperature of -20.
The aqueous recording liquid according to the above 4, wherein the aqueous recording liquid is an acrylic resin in a temperature range of ４０40 ° C.

6. The maximum particle size of the anionic microencapsulated pigment is 1000 nm or less, the average particle size is 300 nm
Or less, and the maximum particle size of the organic pigment or carbon black is 200 nm or less, and the average particle size of the primary particles is 10
The aqueous recording liquid according to any one of the above 2 to 5, which is in a range of １００100 nm,

[0015] 7. Anionic microencapsulated pigment, a mixture containing an anionic organic polymer compound and a pigment having self-dispersion ability in water as an organic solvent phase, or water is added to the organic solvent phase, or Self-dispersion by injecting the organic solvent phase into water (phase inversion emulsification)
What was obtained by, or a part or all of the anionic groups of the organic polymer compounds containing anionic groups is neutralized with a basic compound to impart solubility to water, and the pigment and aqueous After kneading in a medium, the pH is adjusted to neutral or acidic with an acidic compound, and an organic polymer compound containing an anionic group is precipitated (acid-precipitated) and fixed to the pigment to obtain a water-containing solution. The aqueous recording liquid according to any one of the above 1 to 6, wherein the cake is obtained by neutralizing and dispersing some or all of the anionic groups using a basic compound, and

8. An aqueous recording liquid according to any one of the above items 1 to 7, which is used for an ink jet printer.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The anionic microencapsulated pigment used in the aqueous recording liquid of the present invention may contain an organic pigment or carbon black, if necessary, with a curing agent and / or a high molecular compound (however, an anionic organic polymer). Excluding molecular compounds)
With an anionic organic polymer compound having an organic pigment or carbon black content of 35 to 8
0% by weight. Among them, the maximum particle size of the primary particles of the organic pigment or carbon black is 200 nm or less, the average particle size is in the range of 10 to 100 nm, and the maximum particle size of the anionic microencapsulated pigment is 10
Those having an average particle diameter of not more than 00 nm and an average particle diameter of not more than 300 nm are particularly preferred.

Further, the anionic organic high molecular compound is
Acid value 30-150 KOHmg / g, number average molecular weight 200
It is also particularly preferable that the acrylic resin having a glass transition temperature of 0 to 20000, preferably an acrylic resin having a glass transition temperature in the range of -20 to 40 ° C. is neutralized with a base.

Further, it is more preferable that the anionic microencapsulated pigment is a pigment-coated form with an anionic organic polymer compound containing a curing agent and / or a polymer compound. .

Further, in the capsule of the microencapsulated pigment in the present invention, an inorganic substance such as titanium or aluminum, a pigment derivative, a pigment dispersant, a pigment wetting agent, an organic solvent, a plasticizer, an ultraviolet absorber, an antioxidant Or other substances such as vehicles for aqueous recording liquids.

The method for producing the anionic microencapsulated pigment contained in the aqueous recording liquid of the present invention includes physical mechanical methods and chemical methods such as coacervation method, interfacial polymerization method and in-situ method. There are two methods.

However, the particle size of the microencapsulated pigment obtained by these conventional methods is large even if the particle size is submicron or smaller, and the ratio of the pigment in the microcapsule is large. Low, when an aqueous recording liquid is produced using this microencapsulated pigment, fineness, color rendering, transparency or color density cannot always be satisfied. There is a need to produce microencapsulated pigments where the proportion of pigment in the capsule is high. Further, microencapsulated pigments obtained by a conventional method are not preferred because the resin concentration in the capsule is high (the pigment concentration is low) and the materials used for the aqueous recording liquid are limited.

The method for producing the anionic microencapsulated pigment used in the aqueous recording liquid of the present invention basically includes mixing an anionic organic polymer compound having a self-dispersibility in water with a pigment. Body (composite or complex)
Or a mixture of a pigment, a curing agent, and an anionic organic polymer compound as an organic solvent phase, and water is poured into the organic solvent phase, or the organic solvent phase is poured into water, and A method of dispersing (phase inversion emulsification) (hereinafter, referred to as “phase inversion method”) is preferable.

Another production method is to neutralize a part or all of the anionic groups of the organic polymer compounds containing anionic groups with a basic compound to impart water-solubility, and to add After kneading in an aqueous medium, the pH is neutralized or acidified with an acidic compound, and an organic polymer compound having an anionic group is precipitated (acid precipitation) and fixed to a pigment by a production method. It is also preferable to obtain a water-containing cake by neutralizing and dispersing a part or all of the anionic groups using a basic compound (hereinafter, referred to as “acid precipitation method”).

By these methods, an aqueous dispersion containing an anionic microencapsulated pigment finer and higher in pigment content than the conventional method can be produced.

In the above-mentioned phase inversion method, it can also be produced by mixing a recording liquid vehicle and additives into an organic solvent phase. In particular, from the viewpoint that a dispersion liquid for a recording liquid can be directly produced, it is more preferable that the dispersion liquid is produced by mixing a recording liquid vehicle into an organic solvent phase.

The pigment contained in the microcapsules of the anionic microencapsulated pigment may be used in order to obtain a sense of density, transparency and color rendering of the recording liquid, or to obtain an average particle diameter of 30%.
In order to produce a fine microencapsulated pigment of 0 nm or less, an organic pigment or carbon black having a maximum particle size of 200 nm or less and an average primary particle size in a range of 10 to 100 nm is preferable.

The kind of the pigment used in the present invention is not particularly limited. However, if only typical ones are exemplified, quinacridone pigments, quinacridone quinone pigments, dioxazine pigments, phthalocyanine pigments may be used as organic pigments.
Anthrapyrimidine pigments, anthanthrone pigments, indanthrone pigments, flavanthrone pigments, perylene pigments, diketopyrrolopyrrole pigments, perinone pigments, quinophthalone pigments, anthraquinone pigments, thioindigo pigments, benzimidazo Ron pigments, isoindolinone pigments, azomethine pigments or azo pigments. Examples of the carbon black include neutral, acidic, and basic carbons.

The hardening agent which may be contained together with the pigment in the microcapsules of the anionic microencapsulated pigment is used for curing the walls of the anionic microencapsulated pigment, or when used in a recording liquid. Used to increase the film strength and, if necessary, a photoinitiator,
It is more preferable to add a polymerization initiator or a catalyst to promote curing.

Examples of these curing agents include amino resins such as melamine resins, benzoguanamine resins and urea resins; phenol resins such as trimethylolphenol and condensates thereof; tetramethylene diisocyanate (TD
I), diphenylmethane diisocyanate (MDI),
Hexamethylene diisocyanate (HDI), naphthalene diisocyanate (NDI), isophorone diisocyanate (IPDI), xylylene diisocyanate (X
DI), polyisocyanates such as their modified or blocked isocyanates; aliphatic amines,
Amines such as aromatic amines, N-methylpiperazine, triethanolamine, morpholine, dialkylaminoethanol and benzyldimethylamine; polycarboxylic acids,
Acid anhydrides such as phthalic anhydride, maleic anhydride, hexahydrophthalic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bistrimellitate; bisphenol A type epoxy resins, phenolic epoxy resins, and glycidyl methacrylate Epoxy compounds such as polymers, glycidyl ester resins of carboxylic acids, and cycloaliphatic epoxies; polyether polyols, polybutadiene glycols, polycaprolactone polyols, trishydroxyethyl isocyanate (THEI)
Alcohols such as C); polyvinyl compounds and polyallyl compounds as unsaturated group-containing compounds used for radical curing or UV curing or electron beam curing with peroxides;
Vinyl compounds such as a reaction product of glycol or polyol with acrylic acid or methacrylic acid, and the like.

Examples of the photoinitiator used for such a purpose include, but are not limited to, benzoins, anthraquinones, benzophenones, sulfur-containing compounds, dimethylbenzyl ketal, and the like.

Similarly, as the polymerization initiator, for example, t
Peroxides such as -butylperoxybenzoate, di-t-butyl peroxide, cumene peroxide, acetyl peroxide, benzoyl peroxide, lauroyl peroxide; azobisisobutylnitrile, azobis-2,4-dimethylvalero Examples include azo compounds such as nitrile and azobiscyclohexanecarbonitrile.

Similarly, examples of the catalyst include a cobalt compound and a lead compound.

The polymer compound which may be contained together with the pigment in the microcapsules of the anionic microencapsulated pigment can be used without particular limitation as long as it has a number average molecular weight of 1,000 or more. It is preferable that the number average molecular weight is in the range of 3,000 to 100,000 from the viewpoint of the film strength of the recording liquid and the ease of manufacturing the capsule.

The type of such a high molecular compound is not particularly limited, and examples thereof include polyvinyl compounds such as vinyl chloride, vinyl acetate, polyvinyl alcohol and polyvinyl butyral; polyester compounds such as alkyd resin and phthalic acid resin;
Amino resins such as melamine resin, melamine formaldehyde resin, aminoalkyd co-condensation resin, urea resin, urea resin; thermoplastic, thermosetting or modified acrylic, epoxy, polyurethane, polyether, polyamide, unsaturated Examples include polyester-based, phenol-based, silicone-based, fluorine-based and other high molecular compounds, or copolymers or mixtures thereof.

The anionic organic high molecular compound constituting the anionic microencapsulated pigment is not particularly limited as long as it has an anionic group neutralized with a base. In order to obtain a sufficient coating film, usually, the number average molecular weight is 2,0.
It is preferably in the range of 00 to 20,000,
Particularly preferred is a range of 0 to 18,000, and
Those which are dissolved in an organic solvent to form a solution are preferred.

The anionic organic high molecular compounds include:
For example, an anionic group in an organic polymer compound having an anionic group such as a carboxyl group, a sulfonic acid group, or a phosphonic acid group is converted to an organic amine such as ammonia or triethylamine, sodium hydroxide, potassium hydroxide or lithium hydroxide. And the like, which can be obtained by neutralization using an alkali metal hydroxide, such as those imparted with self-dispersion or dissolving ability in water by the neutralization. Particularly desirable self-dispersing ability or dissolving ability is a form in which a carboxyl group in organic polymer compounds having a carboxyl group is neutralized with a base. These anionic group-containing organic polymer compounds may have two or more of these anionic groups.

The amount of the carboxyl group in the organic polymer compounds having a carboxyl group is such that the acid value is 30 to 150 KO.
Hmg / g is preferred, and 50 to 150 KOHmg
/ G is more preferable. If the acid value of the polymer compound exceeds 150, the hydrophilicity becomes too high,
If the storage stability of the capsule is impaired or the water resistance of the recorded image tends to be remarkably reduced, and if the acid value is lower than 30, the stability of the capsule is impaired or the particle diameter tends to be increased. Is not preferred.

Further, the acid value is 30 to 150 KOHmg /
The glass transition temperature (Tg) of the organic polymer compound (g) is
The range of -20 to 40C is preferred. When the Tg is higher than 40 ° C., the resolubility of the recording liquid deteriorates, and when printing is not performed for a long time, the recording liquid dries at the nozzle tip and printing cannot be performed. When the Tg is lower than −20 ° C., the recorded image becomes sticky. It is not preferable because of the tendency.

The organic high molecular compound having such an anionic group may be any one which can impart self-dispersing ability and dissolving ability to water by neutralizing the anionic group. Polyvinyl resin, polyester resin, amino resin, acrylic resin, epoxy resin, polyurethane resin, polyether resin,
Examples of the resin include a polyamide resin, an unsaturated polyester resin, a phenol resin, a silicone resin, a fluorine-based polymer compound, a mixture thereof, and a resin having an anionic group.

Acrylic resins are preferable among the organic polymer compounds having an anionic group. The acrylic resin contains acrylic acid and / or methacrylic acid as its essential components and its alkyl ester and / or its hydroxyalkyl ester. Acrylic resins containing styrene as necessary and having a total content of these acrylic monomers and styrene of 80% by weight or more are particularly preferred.

The anionic organic high molecular compound used in the present invention has a sufficient molecular weight as a capsule wall material, but further improves the properties such as solvent resistance and durability of the capsule wall. In order to increase the film strength of the recording liquid after the formation of the film, the anionic organic polymer compounds used in advance may be added to a glycidyl group, an isocyanate group, a hydroxyl group or an α, β-ethylenically unsaturated diamine. By pending a reactive active group such as a heavy bond (vinyl group), or by mixing the above-mentioned curing agent or the like, at the time of or after formation of the capsule, or by coating the recording liquid After formation, the molecular weight of the anionic organic polymer compound itself for the capsule wall material may be increased, or the ability to crosslink and gel may be imparted. Is more preferable.

Among the organic polymer compounds having an anionic group, the acrylic resin includes, for example, an anionic group-containing acrylic monomer and, if necessary, another monomer copolymerizable with these monomers. It is obtained by polymerization in water. Examples of the anionic group-containing acrylic monomer include, for example, an acrylic monomer containing one or more anionic groups selected from the group consisting of a carboxyl group, a sulfonic acid group, and a phosphone group, and among these, an acrylic monomer having a carboxyl group Is particularly preferred.
It is also preferable to use a monomer having a crosslinkable functional group in order to improve the solvent resistance and durability of the capsule wall and to increase the film strength of the recording liquid after forming the film.

Examples of the acrylic monomer having a carboxyalkyl group include acrylic acid, methacrylic acid, crotonic acid, ethacrylic acid, propylacrylic acid, isopropylacrylic acid, itaconic acid, fumaric acid and the like. Among these, acrylic acid and methacrylic acid are preferred.

Examples of the acrylic monomer having a sulfonic acid group include sulfoethyl methacrylate and butylacrylamide sulfonic acid.

Examples of the acrylic monomer having a phosphone group include phosphoethyl methacrylate.

Other monomers copolymerizable with the anionic group-containing acrylic monomer include, for example, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-propyl acrylate, n-butyl acrylate, and n-butyl acrylate. t-butyl, 2-ethylhexyl acrylate, n-octyl acrylate, lauryl acrylate,
Benzyl acrylate, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, methacrylic acid
n-propyl, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, lauryl methacrylate, stearyl methacrylate,
(Meth) acrylates such as tridecyl methacrylate and benzyl methacrylate;

An addition reaction product of an oil fatty acid such as an addition reaction product of stearic acid and glycidyl methacrylate with a (meth) acrylate monomer having an oxirane structure; an oxirane compound containing an alkyl group having 3 or more carbon atoms and (meth) ) Addition reaction products with acrylic acid; styrene,
styrene-based monomers such as α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-tert-butylstyrene, etc .; itaconic esters such as benzyl itaconate and ethyl itaconate;
Maleic esters such as dimethyl maleate and diethyl maleate; fumaric esters such as dimethyl fumarate and diethyl fumarate;

Acrylonitrile, methacrylonitrile,
Vinyl acetate, isobornyl acrylate, isobornyl methacrylate, aminoethyl acrylate, aminopropyl acrylate, methylaminoethyl acrylate, methylaminopropyl acrylate, ethylaminoethyl acrylate, ethylaminopropyl acrylate, aminoethyl acrylate , Aminopropylamide acrylate, methylaminoethylamide acrylate, methylaminopropylamide acrylate, ethylaminoethylamide acrylate, ethylaminopropylamide acrylate, methacrylamide, aminoethyl methacrylate, aminopropyl methacrylate, methacryl Methylaminoethyl methacrylate, methylaminopropyl methacrylate, ethylaminoethyl methacrylate, ethylaminopropyl methacrylate, methyl methacrylate Noethylamide, aminopropylamide methacrylate, methylaminoethylamide methacrylate, methylaminopropylamide methacrylate, ethylaminoethylamide methacrylate, ethylaminopropylamide methacrylate, hydroxymethyl acrylate, 2-hydroxyethyl acrylate, acrylic Acid
2-hydroxypropyl, hydroxymethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, N-methylolacrylamide, allyl alcohol and the like.

The monomer having a crosslinkable functional group includes
Polymerizable monomer having a blocked isocyanate group, monomer having an epoxy group, 1,3-dioxolan-2
And a monomer having an -on-4-yl group.

The polymerizable monomer having a blocked isocyanate group can be easily obtained by, for example, adding a known blocking agent to a polymerizable monomer having an isocyanate group such as 2-methacryloyloxyethyl isocyanate. Alternatively, it can be easily produced by subjecting a vinyl copolymer having a hydroxyl group and a carboxyl group to an addition reaction with a compound having an isocyanate group and a blocked isocyanate group. A compound having an isocyanate group and a blocked isocyanate group can be easily obtained by subjecting a diisocyanate compound and a known blocking agent to an addition reaction at a molar ratio of about 1: 1.

Examples of the monomer having an epoxy group include glycidyl (meth) acrylate and a (meth) acrylate monomer having an alicyclic epoxy group.

Examples of the monomer having a 1,3-dioxolan-2-one-4-yl group include, for example, 1,3-dioxolan-2-one-4-ylmethyl (meth) acrylate and 1,3-dioxolan-2. -On-4-ylmethyl vinyl ether;

The polymerization initiator used when polymerizing the anionic group-containing acrylic monomer and, if necessary, other monomers copolymerizable with these monomers includes:
For example, t-butyl peroxybenzoate, di-t-
Peroxides such as butyl peroxide, cumene peroxide, acetyl peroxide, benzoyl peroxide, lauroyl peroxide; azobisisobutylnitrile, azobis-2,4-dimethylvaleronitrile,
An azo compound such as azobiscyclohexanecarbonitrile is exemplified.

Solvents used for polymerizing the anionic group-containing acrylic monomer and, if necessary, other monomers copolymerizable with these monomers include, for example, aliphatic solvents such as hexane and mineral spirits. Hydrocarbon solvents; aromatic hydrocarbon solvents such as benzene, toluene and xylene; ester solvents such as butyl acetate; ketone solvents such as methyl ethyl ketone and isobutyl methyl ketone; methanol, ethanol, butanol, isopropyl alcohol and the like Alcohol solvents such as dimethylformamide, dimethylsulfoxide, N
Aprotic polar solvents such as -methylpyrrolidone, pyridine and the like. These solvents can be used in combination of two or more kinds.

The aqueous dispersion containing the anionic microencapsulated pigment by the phase inversion method is produced as follows.

In the phase inversion method, a mixture (composite or composite) of an anionic organic polymer compound having a self-dispersing property in water and a pigment, or a pigment, a curing agent, and an anionic organic polymer compound The organic solvent used when the mixture with the organic solvent phase is used is not particularly limited, and any organic solvent can be used as long as it can dissolve the anionic organic polymer compounds. From the viewpoint of easy removal of the solvent at the time, ketone solvents such as acetone and methyl ethyl ketone; ester solvents such as ethyl acetate; alcohol solvents such as ethanol and isopropyl alcohol; aromatic hydrocarbon solvents such as benzene; Boiling solvents are preferred.

The proportion of the anionic organic high molecular compounds is as follows:
The range is preferably from 25 to 186 parts by weight, particularly preferably from 30 to 150 parts by weight, based on 100 parts by weight of the pigment.

Particularly, it is desirable for the mixture (composite or composite) that is an organic solvent phase that the pigment is finely and uniformly dispersed in the organic solvent phase in which the anionic organic polymer compound is dissolved. This means that, without aggregation, the dispersion is stabilized and, at the same time, the curing agent and the polymer compound are compatible with the anionic organic polymer compound, if necessary. It is not limited.

The method for stabilizing the dispersion of the mixture is not particularly limited. However, among those, only typical ones are exemplified. Using various dispersing machines such as a roll mill or a sand mill, an anionic organic polymer compound is finely dispersed in an organic solvent phase in which the anionic organic polymer compound is dissolved, and then the curing agent or the polymer compound is dissolved or dispersed. Or (2) a wet cake after the synthesis of the pigment, that is, a state in which the pigment is dispersed in water, in an anionic organic polymer compound before neutralization. Then, using various dispersers such as kneaders, to finely disperse by flashing, and then to dissolve or disperse the curing agent and polymer compound, etc. Manner, and the like. In these dispersion methods, in order to obtain ultrafine particles, a method of bead mill dispersion or flushing is more preferable.

In the latter method, in particular, since a wet cake is used, a drying step of organic pigments is not required, so that energy is saved, and no strong coagulation occurs during the drying step. Therefore, it is extremely useful.

Further, in order to stabilize the dispersion, pigment derivatives having a dialkylaminomethyl group, a sulfone group, a sulfamoyl group, a phthalimide group, etc., “BYK-160” and “BYK-166” manufactured by Big Chemie, manufactured by Zeneca The use of a pigment dispersant such as “Sol Sperse 24000” described above can also shorten the dispersion time and the like.

In order to facilitate self-dispersion (phase inversion emulsification) and to simplify the operation of removing the solvent, it is desirable to use as little solvent as possible in the mixture. , The viscosity of these mixtures is 10
It is desirable to adjust to 000 cp or less.

The self-dispersion (phase inversion emulsification) is performed by adding water to the organic solvent phase of the mixture or by adding the organic solvent phase to water. The method is as follows. The desired microencapsulated pigment can be instantaneously formed by slowly charging one of the water into the other while appropriately stirring the water.

In such stirring, the type and speed of the stirrer do not significantly affect the size of the formed particles, and thus the type and speed of the stirrer are not particularly limited.

In such a production method, it is possible to produce a sufficiently fine microencapsulated pigment by the above-mentioned procedure.
This is to emulsify the phase while applying ultrasonic waves to the organic phase. The frequency of the ultrasonic wave is not particularly limited, but is preferably 10 to 200 KHz.

In order to neutralize organic polymer compounds having anionic groups, it is necessary to dissolve a necessary amount of a neutralizing base in an organic solvent phase or an aqueous phase in advance. . In particular, it is more preferable to dissolve the bases in the aqueous phase in consideration of the aggregation of the pigment in the organic solvent phase.

Further, a hardening agent used for gelling the formed capsule wall or for increasing the film strength after forming the film of the recording liquid is, for example, a water-soluble compound such as polyamines. Even if used,
It is necessary to dissolve the necessary amount in the organic solvent phase.

The resulting aqueous dispersion containing an anionic microencapsulated pigment can be used as it is, or can be used as an aqueous dispersion by removing the solvent, depending on the form used for practical use.

Examples of the method for removing the solvent include a general distillation method and a reduced pressure distillation method.

On the other hand, using the same materials as described above, a water-containing cake made of an organic polymer having an anionic group and a pigment obtained by acid precipitation is mixed with an anionic group using a basic compound. A method (acid precipitation method) of obtaining an aqueous dispersion containing an anionic microencapsulated pigment by neutralizing a part or all of the pigment is as follows.

(1) An organic polymer compound having an anionic group and a pigment are dispersed in an alkaline aqueous medium.
In addition, a heat treatment is performed as necessary to achieve gelling of the resin. (2) The organic polymer compounds are made hydrophobic by making the pH neutral or acidic, and these are strongly fixed to the pigment. In addition, a heat treatment is performed as necessary to achieve gelling of the resin.

(3) If necessary, perform filtration and water washing. (4) Carboxyl groups are neutralized with a basic compound, and the pigment is redispersed in an aqueous medium. In addition, a heat treatment is performed as necessary to achieve gelling of the resin.

As the method of dispersing the pigment in the step (1), the following two methods are suitable. (1-1) A pigment is kneaded with an organic polymer compound having an anionic group that has been neutralized or not neutralized in an organic solvent medium, and then dispersed in an aqueous medium.

(1-2) In an aqueous medium, a neutralized organic polymer having an anionic group and a pigment are mixed or kneaded.

In the above method (1-1), first, a pigment and an organic solvent solution of an organic polymer having an anionic group are dissolved in a known dispersing machine such as a ball mill, a sand mill, and a colloid mill. And disperse finely.

At this time, as the organic solvent to be used, any commonly used organic solvent can be used, but it has good solubility in the resin and has no problem in the synthesis of the resin. It is preferable to use a material that is easy to mix and further miscible with water. As such a solvent, for example,
Examples include acetone, methyl ethyl ketone, methanol, ethanol, n-propanol, isopropanol, ethyl acetate, and tetrahydrofuran. Low miscibility with water, but methyl isopropyl ketone, methyl-n-
Propyl ketone, isopropyl acetate, n-propyl acetate, methylene chloride, benzene and the like can also be used in this method.

In order to disperse a dispersion of a pigment dispersed in an organic solvent medium and an organic polymer compound having an anionic group in an aqueous medium, an anionic group of the organic polymer compound having an anionic group is used. Is neutralized with a basic compound to make it hydrophilic and dispersed in water, or from an anionic organic polymer compound and pigment obtained by neutralizing an anionic group using a basic compound. And dispersing the resulting dispersion in water.

As a method of dispersing in water, the following method is suitable. (A) After neutralizing a dispersion comprising an organic polymer compound having an anionic group and a pigment using a basic compound,
Add water dropwise. (B) Water is added dropwise to a dispersion comprising an organic polymer compound having an anionic group and a pigment neutralized with a basic compound and a pigment. (C) Water containing a basic compound is dropped into a dispersion comprising an organic polymer compound having an anionic group and a pigment. (D) A dispersion composed of an organic polymer compound having an anionic group and a pigment is neutralized with a basic compound and added to an aqueous medium. (E) A dispersion comprising an anionic organic polymer compound and a pigment obtained by neutralization with a basic compound is added to an aqueous medium. (F) A dispersion comprising an organic polymer compound having an anionic group and a pigment is added to an aqueous medium containing a basic compound.

When dispersing in water, ordinary low shear stirring, high shear stirring with a homogenizer or the like, or ultrasonic waves may be used.

Examples of the basic compound include alkali metals such as sodium hydroxide, potassium hydroxide and lithium hydroxide; ammonia, triethylamine, tributylamine, dimethylethanolamine, monoethanolamine, diethanolamine, triethanolamine and diisopropanol. Amines, organic amines such as morpholine, and the like.

In the above method (1-2), first, the anionic groups of the organic polymer compounds having anionic groups are neutralized and dissolved by using the above-mentioned basic compound, and the aqueous medium is dissolved. Mix or knead with the pigment inside. At this time, the resin dissolved in water may contain an organic solvent, or the medium may be substantially water only after the solvent is removed. As the pigment, any of a powder pigment, an aqueous slurry, and a press cake can be used. When the pigment is dispersed in an aqueous medium, it is preferable to use an aqueous slurry or a press cake with less secondary aggregation of the pigment particles in order to simplify the production process. As the kneading method, the organic solvent and the basic compound, the same method and the same material as those in the case of dispersion in an organic solvent medium can be used.

Regardless of the kneading method using an organic solvent or an aqueous solvent, a pigment dispersant or wetting agent is used for the purpose of assisting the dispersion of the pigment within a range that does not reduce the water resistance of the recorded image. You can also.

When the pigment is kneaded or after kneading and before acid precipitation, substances other than the pigment, for example, a dye, an antioxidant, an ultraviolet absorber, a curing catalyst for a coating binder, a rust preventive, etc. Agents, fragrances, drugs and the like can also be added.

The proportion of the anionic organic high molecular compound used is suitably in the range of 25 to 200 parts by weight, preferably 30 to 150 parts by weight, per 100 parts by weight of the organic pigment. The use ratio of anionic organic polymer compounds is 2
If the amount is less than 5 parts by weight, the pigment tends to be difficult to disperse sufficiently finely. If the amount is more than 200 parts by weight, the proportion of the pigment in the dispersion decreases, and the aqueous pigment dispersion is added to the recording liquid. When used, there is a tendency that there is no room for formulation design, which is not preferable.

Further, when the pigment is kneaded and then subjected to a heat treatment to gel the anionic organic polymer compound, the non-volatile content of the kneaded dispersion is 15% by weight or less, preferably 1% by weight.
It is preferable to carry out at 0% by weight or less.

There is no problem if the heating temperature is equal to or higher than the temperature at which the curing of the anionic organic polymer proceeds, but the preferred temperature range is 70 ° C. to 200 ° C. 7
At a temperature of 0 ° C. or less, the curing time is too long, and 200 ° C.
If it is above, depending on the kind of the pigment, crystal growth or dispersion stability is broken, and it is difficult to encapsulate.

The acid precipitation performed for the purpose of strongly fixing the anionic organic high molecular compound to the pigment finely dispersed in the aqueous medium is carried out by the anionic organic high molecular compound obtained by neutralization with the basic compound. Are adjusted to pH by adding acidic compounds.
Is rendered hydrophobic by making it neutral or acidic.

As the acidic compound used, for example,
Inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid and nitric acid; formic acid, acetic acid,
Organic acids such as propionic acid can be used, but hydrochloric acid or sulfuric acid, which has a small amount of organic substances in the waste water and has a large acid precipitation effect, is preferred. The pH at the time of acid precipitation is preferably in the range of 2 to 6, but some pigments are decomposed by an acid. In the case of such a pigment, the acid precipitation is preferably in the range of pH 4 to 7. It is preferable to remove the organic solvent present in the system before the acid precipitation by using a method such as distillation under reduced pressure.

After acid precipitation, if necessary, filtration and washing with water are performed to obtain a water-containing cake of the dispersed pigment. As a filtration method,
Known methods such as suction filtration, pressure filtration, and centrifugation can be employed.

This wet cake was dried without drying.
By re-neutralizing the anionic group with a basic compound in a state of being hydrated, the pigment particles are re-dispersed in an aqueous medium while keeping a fine state without agglomeration.

The amount of the basic compound used for the re-neutralization is not particularly limited as long as the particles can be loosened, and the pH in the system is usually 7 or more, preferably 7.5.
Used to be. In addition, a method of re-dispersion, a basic compound is added, and a simple stirrer such as a disper is sufficient. Further, a dispersing machine such as an ultrasonic dispersing machine or a nanomother can be used.

The basic compound used for the re-neutralization includes
Considering the re-dispersibility and water resistance of the recording liquid, sodium hydroxide, potassium hydroxide, alkali metal hydroxides such as lithium hydroxide and triethanolamine, organic solvents such as diethanolamine and the like which are difficult to volatilize alone or Combination with volatile amine compounds such as ammonia, triethylamine and dimethylethanolamine is preferred.

As described above, the anionic microencapsulated pigment used in the present invention enables encapsulation of fine particles without using any so-called auxiliary material such as an emulsifier, and is extremely simple. Thus, microcapsules can be prepared.

The average particle size of the pigment in the microencapsulated pigment used in the present invention is determined by adding the major and minor diameters of several tens of samples of the pigment using a photograph taken with an electron microscope and using the measured value. .

The average particle size of the microencapsulated pigment used in the present invention is slightly different depending on the method of measuring the particle size. Therefore, it is preferable to use an actually measured value measured with an electron microscope. Can also be measured by using a particle size measuring device described above.

The anionic microencapsulated pigment thus obtained has improved dispersion stability of the pigment more than before, and can be used as a coloring material for aqueous recording liquids.
There is an advantage that the performance of the aqueous recording liquid such as definition, light resistance, color rendering, transparency and the like is improved. In addition, since the pigment concentration in the microcapsules is high, the color density of the recording liquid is sufficiently high, and a highly reliable recording liquid can be provided without clogging of nozzles after the recording liquid is left for a long time.

The content of the pigment in the anionic microencapsulated pigment is preferably in the range of 35 to 80% by weight. Pigment content in the anionic microencapsulated pigment is 35
%, The resin concentration in the capsule becomes high, so that the compatibility with the resin for the recording liquid, the solvent, and the additives such as the auxiliaries may be limited, or the amount of the additive or the like may be reduced. Lack of versatility due to being restricted, and furthermore, since the pigment concentration in the capsule is low, when used as an aqueous dispersion as a recording liquid, the color density cannot be increased or the color density is increased. As a result that the use ratio of the microencapsulated pigment in the recording liquid must be increased, the viscosity of the recording liquid tends to increase, which is not preferable. On the other hand, when the content of the pigment in the anionic microencapsulated pigment is more than 80% by weight, the pigment tends to be hardly finely dispersed, which is not preferable.

When the maximum particle size of the anionic microencapsulated pigment is larger than 1000 nm, the nozzle of the jet ink printer may be clogged, and the maximum particle size of the anionic microencapsulated pigment is 1000 nm or less. , 500 nm or less is more preferable.

The average particle size of the pigment in the anionic microencapsulated pigment is preferably 300 nm or less, particularly preferably 250 nm or less. If the average particle size of the organic pigment used is larger than 300 nm, the microencapsulated pigment in the dispersion may be settled or may be encapsulated in a state of aggregation during microencapsulation when the pigment is stored for a long time. When used as a recording liquid, the coloring property, transparency, and definition are poor. In particular, when recording is performed on an OHP sheet or the like, light transmission tends to be interrupted and a beautiful color tends not to be projected, which is not preferable.

The anionic organic high molecular compounds in the anionic microencapsulated pigment of the present invention are preferably used in the form of a salt of an alkali metal or an organic amine. When an alkali metal hydroxide such as sodium hydroxide, potassium hydroxide or lithium hydroxide is used, the inorganic base remains in the recorded image, and the water resistance of the recorded image tends to deteriorate. It is preferable because it has excellent solubility and increases the reliability of the recording liquid.

Examples of the organic amine include volatile amine compounds such as ammonia, triethylamine, tributylamine, dimethylethanolamine, diisopropanolamine and morpholine, and organic amines having a high boiling point such as diethanolamine and triethanolamine, which are difficult to volatilize. Is preferred from the viewpoint of re-dissolvability.

When the anionic microencapsulated pigment in the present invention is prepared in an aqueous dispersion, the content of the anionic microencapsulated pigment in the aqueous dispersion is 100 parts by weight of the aqueous dispersion. 70 parts by weight or less is preferable,
The range of 2 to 60 parts by weight is more preferable, and the range of 10 to 50 parts by weight is particularly preferable. When the content of the microencapsulated pigment in the aqueous dispersion is higher than 70 parts by weight, since the aqueous dispersion substantially tends to exhibit a solid state, aggregation of the microcapsules occurs and the dispersion needs to be performed again. Is not preferred. On the other hand, if the content of the microencapsulated pigment in the aqueous dispersion is less than 2 parts by weight, the color density tends to be insufficient when used in an aqueous recording liquid, which is not preferable. Considering that an additive for improving the performance is added to the aqueous recording liquid, when the content of the microencapsulated pigment in the aqueous dispersion is less than 10 parts by weight, the amount of the additive is limited. It is not preferable because of the tendency.

The aqueous recording liquid of the present invention comprises (1) an anionic microencapsulated pigment obtained by coating an organic pigment or carbon black with an organic polymer compound having an anionic group neutralized with a base; and (2) It contains a water-soluble anionic surfactant and / or a nonionic surfactant having an HLB value of 14 or more, and the content ratio of the organic pigment or carbon black in the anionic microencapsulated pigment is 35 to 80% by weight, and a water-soluble organic solvent,
It is prepared by mixing water and the like. Further, if necessary, a water-soluble resin, an organic amine, a preservative, a viscosity adjuster, a pH adjuster,
A chelating agent or the like can be added.

The water-soluble anionic surfactant and the nonionic surfactant having an HLB value of 14 or more used in the aqueous recording liquid of the present invention are not particularly limited as long as they are soluble in water or have an HLB value of 14 or more. Not done.

Examples of the anionic surfactant used in the aqueous recording liquid of the present invention include fatty acid salts such as sodium stearate, potassium oleate and sodium semi-hardened tallow fatty acid; sodium lauryl sulfate, triethanolamine lauryl sulfate; Alkyl sulfates such as higher alcohol sodium sulfate; alkyl benzene sulfonates such as sodium dodecylbenzene sulfonate; alkyl naphthalene sulfonates such as sodium alkyl naphthalene sulfonate; alkyl sulfosuccinates such as sodium dialkyl sulfosuccinate; alkyl diphenyl ether disulfonic acid Alkyl diphenyl ether disulfonate such as sodium; alkyl phosphate such as potassium alkyl phosphate; sodium polyoxyethylene lauryl ether sulfate, poly Alkyl aryl sulfuric acid ester salts of polyoxyethylene alkyl phenyl ether sulfate and the like; alkoxy polyoxyethylene alkyl polyoxyethylene alkyl sulfate ester salts such as sulfuric acid triethanol amine;
Polyoxyethylene alkyl phosphate, formalin naphthalene sulfonic acid condensate and the like can be mentioned.

HLB value 1 used in the aqueous recording liquid of the present invention
Examples of the four or more nonionic surfactants include polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, and polyoxyethylene alkyl such as polyoxyethylene higher alcohol ether. Ethers; polyoxyethylene alkyl allyl ethers such as polyoxyethylene octyl phenyl ether and polyoxyethylene nonyl phenyl ether;
Polyoxyethylene derivative, oxyethylene / oxypropylene block copolymer, sorbitan fatty acid ester, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, poly Polyoxyethylene sorbitan fatty acid esters such as oxyethylene sorbitan monooleate and polyoxyethylene sorbitan trioleate; polyoxyethylene sorbitol fatty acid esters such as polyoxyethylene sorbite tetraoleate; and glycerin fatty acid esters.

In particular, among the above surfactants, sorbitan-based surfactants have low stability of the anionic microencapsulated pigment, low resolubility of the recording liquid, and low viscosity of the recording liquid.
This is preferable because the printing speed can be increased and the generation of bubbles is small.

The content of the anionic microencapsulated pigment in the aqueous recording liquid of the present invention depends on the color density of the aqueous recording liquid,
From the viewpoints of definition, transparency and hue saturation, the recording liquid 10
The content is preferably in the range of 1 to 30% by weight in 0 part by weight, and 3 to 20%.
A range of weight% is particularly preferred.

The content of the above surfactant is preferably in the range of 0.1 to 20% by weight, more preferably 0.5 to 10% by weight, based on 100 parts by weight of the aqueous recording liquid in view of the stability and viscosity of the aqueous recording liquid. Is particularly preferred. If the amount of the surfactant is small, non-discharge is likely to occur particularly in a thermal inkjet printer, and if it exceeds 20% by weight, the viscosity of the liquid tends to increase and the water resistance of the recorded image tends to deteriorate. Is not preferred.

Examples of the water-soluble organic solvent used for the aqueous recording liquid include methyl alcohol, ethyl alcohol, and n.
-Butyl alcohol, isobutyl alcohol, tert
Alcohols such as -butyl alcohol, n-propyl alcohol and isopropyl alcohol; amides such as dimethylformaldehyde and dimethylacetamide; ketones such as acetone and methyl ethyl ketone; tetrahydrofuran, dioxane, ethylene glycol methyl ether, ethylene glycol ethyl ether and diethylene glycol methyl Ethers such as ether, diethylene glycol ethyl ether, triethylene glycol monomethyl ether, and triethylene ethylene glycol monoethyl ether; ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, Diethylene glycol, polyethylene glycol,
Polyhydric alcohols such as polypropylene glycol and glycerin; N-methyl-pyrrolidone, 1,3-dimethyl-
2-imidazolidinone and the like. Among these water-soluble organic solvents, polyhydric alcohols and ethers are preferable.

The content of the water-soluble organic solvent in the aqueous recording liquid is preferably 50% by weight or less, and particularly preferably in the range of 5 to 40% by weight.

Examples of the water-soluble resin used as necessary for the aqueous recording liquid include natural proteins such as glue, gelatin, casein, albumin, gum arabic, and fish grew, alginic acid, methylcellulose, carboxymethylcellulose, polyethylene oxide, and hydroxyethylcellulose. And synthetic polymers such as polyvinyl alcohol, polyacrylamide, polyaromatic amide, polyacrylic acid, polyvinyl ether, polyvinylpyrrolidone, polyester, styrenemaleic acid, styreneacrylic acid resin, and copolymers thereof.

The water-soluble resin is used as needed for the purpose of improving the fixing property, adjusting the viscosity and drying quickly.
The content of the water-soluble resin in the aqueous recording liquid is 30% by weight.
Or less, particularly preferably 20% by weight or less.

Examples of the organic amine used as necessary in the aqueous recording liquid include, for example, ethanolamine, diethanolamine, triethanolamine, N-methylethanolamine, N-ethyldiethanolamine, 2-amino-
2-methylpropanol, 2-ethyl-2-amino-
Examples thereof include 1,3-propanediol, 2- (aminoethyl) ethanolamine, tris (hydroxymethyl) aminomethane, ammonia, piperidine, and morpholine.

In the method for producing an aqueous recording liquid of the present invention, the anionic microencapsulated pigment may be dispersed, if necessary, using a disperser such as a bead mill, a roll mill, or a sand mill, or simply by dispersing. After dispersing with a simple stirrer such as, a water-soluble surfactant or a surfactant having an HLB value of 14 or more, a water-soluble organic solvent, water,
It can be produced by an operation of stirring and mixing with a water-soluble resin or the like. In addition, if necessary, other surfactants, preservatives, viscosity adjusters, pH adjusters, chelating agents and the like can be added at the time of stirring to produce the composition.

As a method for forming a recorded image using the aqueous recording liquid prepared as described above, various papers, sheets, and the like can be formed by using an on-demand type inkjet printer.
Print on film, fiber, metal, etc.

The ink jet printer is not particularly limited, and examples thereof include a piezo type using a piezoelectric element in a printer head, and a heat type in which thermal energy is applied to a recording liquid to discharge ink as droplets from micropores for recording. can give.

Further, it is also possible to fix the image by applying energy such as heat or ultraviolet light after printing.

An electric signal of an image to be recorded is given to these ink jet printers, and a full-color recorded image is obtained using the above ink.

The aqueous recording liquid thus produced is
By using it for jet printers such as piezo type and thermal type, the definition, color development, transparency,
Excellent water resistance and re-dissolving properties, furthermore, there is no liquid pool at the nozzle tip of the jet printer, excellent storage stability of the liquid, and even if the jet printer is left unused for a long time, there is no clogging of the nozzle Can be printed under high reliability. Furthermore, a stable recorded image can be obtained without causing ejection failure even in high-speed printing of a thermal type ink jet printer.

[0122]

The present invention will be described below in more detail with reference to Examples and Comparative Examples. In the following, "part" and "%"
Represents "parts by weight" and "% by weight" unless otherwise specified.

Synthesis Example 1 (Synthesis of Organic Polymer Compounds Having Anionic Group) 175 parts of n-butyl methacrylate, 10.7 parts of n-butyl acrylate, 37.5 parts of β-hydroxyethyl methacrylate, 26. A mixed liquid comprising 8 parts and 5.0 parts of “perbutyl O” [tert-butyl peroxyoctoate manufactured by NOF Corporation] was prepared.

Next, 250 parts of methyl ethyl ketone were charged into a flask, and stirred under a nitrogen blanket while stirring.
After the temperature was raised to 0 ° C, the above mixture was added dropwise over 2 hours. After the addition was completed, the mixture was further reacted at the same temperature for 15 hours to obtain a vinyl resin having an acid value of 70 and a number average molecular weight of 12,500. Was obtained. The nonvolatile content of this resin solution was 48%. Hereinafter, this is abbreviated as resin solution (A-1).

Synthesis Example 2 (same as above) 175 parts of n-butyl methacrylate, 10.7 parts of n-butyl acrylate, 37.5 parts of β-hydroxyethyl methacrylate, 26.8 parts of methacrylic acid and 20.0 parts of “perbutyl O” Was prepared.

Next, 250 parts of methyl ethyl ketone was charged into a flask and stirred under a nitrogen blanket while stirring.
After the temperature was raised to 0 ° C, the above mixture was added dropwise over 2 hours. After completion of the addition, the mixture was further reacted at the same temperature for 15 hours to obtain a vinyl resin having an acid value of solids of 68 and a number average molecular weight of 5,600. Was obtained. The nonvolatile content of this resin solution was 50%. Hereinafter, this is abbreviated as resin solution (A-2).

Synthesis Example 3 (Same as above) 153.8 parts of n-butyl methacrylate, 20.4 parts of n-butyl acrylate, 37.5 parts of β-hydroxyethyl methacrylate, 38.3 parts of methacrylic acid, and “Perbutyl O” 5. A mixture of 0 parts was prepared.

Next, 250 parts of methyl ethyl ketone was charged into a flask and stirred under a nitrogen blanket with stirring.
After the temperature was raised to 0 ° C., the above mixture was added dropwise over 2 hours. After the addition was completed, the mixture was further reacted at the same temperature for 15 hours to obtain a vinyl resin having an acid value of 98 of solids and a number average molecular weight of 12,500. Was obtained. The nonvolatile content of this resin solution was 51%. Hereinafter, this is abbreviated as resin solution (A-3).

Synthesis Example 4 (Same as above) 171.4 parts of n-butyl methacrylate, 6.3 parts of n-butyl acrylate, 37.5 parts of β-hydroxyethyl methacrylate, 34.8 parts of acrylic acid and “Perbutyl O” A mixture of 0 parts was prepared.

Next, 250 parts of methyl ethyl ketone was charged into a flask, and stirred under a nitrogen blanket while stirring.
After raising the temperature to 0 ° C., the above mixture was added dropwise over 2 hours. After completion of the addition, the mixture was further reacted at the same temperature for 15 hours to obtain a vinyl resin having an acid value of solids of 95 and a number average molecular weight of 8800. Was obtained. The nonvolatile content of this resin solution was 50%. Hereinafter, this is abbreviated as resin solution (A-4).

Synthesis Example 5 (Synthesis of Organic Polymer Compounds Having Anionic Group—for Gelation Treatment) 83.8 parts of n-butyl methacrylate, 89.4 parts of n-butyl acrylate, β-hydroxyethyl methacrylate 5 parts, methacrylic acid 26.7 parts, glycidyl methacrylate 12.5 parts and "Perbutyl O" 2
A mixture of 0.0 parts was prepared.

Next, 250 parts of methyl ethyl ketone was charged into a flask, and stirred under a nitrogen blanket while stirring.
After the temperature was raised to 0 ° C., the above mixture was added dropwise over 2 hours. After the addition was completed, the mixture was further reacted at the same temperature for 15 hours to obtain a vinyl resin having an acid value of solids of 69 and a number average molecular weight of 10,400. Was obtained. The nonvolatile content of this resin solution was 50%. Hereinafter, this is abbreviated as resin solution (A-5).

Synthesis Example 6 (Synthesis of organic polymer compounds having anionic group) 51.0 parts of n-butyl methacrylate, 126.7 parts of n-butyl acrylate, 37.5 parts of β-hydroxyethyl methacrylate, acrylic acid A mixture was prepared consisting of 34.8 parts and 5.0 parts of "Perbutyl O".

Next, 250 parts of methyl ethyl ketone were charged into a flask, and stirred under a nitrogen blanket while stirring.
After the temperature was raised to 0 ° C., the above mixture was added dropwise over 2 hours. After the addition was completed, the mixture was further reacted at the same temperature for 15 hours to obtain a solid having an acid value of 97, a number average molecular weight of 13200, and a glass transition temperature. A solution of a vinyl resin having a (Tg) of −14 ° C. was obtained. The nonvolatile content of this resin solution was 50%. Less than,
This is abbreviated as resin solution (A-6).

Synthesis Example 7 (Same as above) 98.0 parts of styrene, 36.8 methyl methacrylate
Parts, n-butyl acrylate 49.0 parts, β-hydroxyethyl methacrylate 39.2 parts, methacrylic acid 2
A mixed solution consisting of 7.0 parts and 5.0 parts of "Perbutyl O" was prepared.

Next, 250 parts of methyl ethyl ketone was charged into a flask, and stirred under a nitrogen blanket while stirring.
After the temperature was raised to 0 ° C, the above mixture was added dropwise over 2 hours. After the addition was completed, the mixture was further reacted at the same temperature for 15 hours to obtain a solid having an acid value of 76, a number average molecular weight of 17,800 and a Tg of 4
A 5 ° C. vinyl resin solution was obtained. The nonvolatile content of this resin solution was 48%. Hereafter, this is called a resin solution (A-
Abbreviated as 7).

Resin solutions (A-1) obtained in Synthesis Examples 1 to 7
Table 1 below summarizes the nonvolatile content, the molecular weight of the resin, the acid value, and the glass transition temperature (Tg) of (A-7).

[0138]

[Table 1]

Production Example 1 (Production of an aqueous dispersion containing a cyan anionic microencapsulated pigment) 22.1 parts of the resin solution (A-3) obtained in Synthesis Example 3, "Fastgen Blue TGR" ( Dainippon Ink and Chemicals
C.I. I. Pigment Blue 15: 3, average particle diameter 50 nm, maximum particle diameter 100 nm) 14.25 parts, and dimethylaminomethyl copper phthalocyanine 0.2 as a dispersing aid.
75 parts, methyl ethyl ketone 78.2 parts, "Super
4.7 parts of Becamine L-109-60 (a melamine resin manufactured by Dainippon Ink and Chemicals, Inc.) and 300 parts of ceramic beads having an average particle size of 0.5 mm were placed in a stainless steel container, and then placed. After the mixture was dispersed using a bead mill disperser, the ceramic beads were filtered off,
A paste for microencapsulated pigment was prepared.

Next, after adding 40.0 parts of the paste for microencapsulated pigment and 0.4 part of diethanolamine in a polycup, they were mixed with a stirrer to form an organic solvent phase. While stirring and irradiating ultrasonic waves of 45 KHz to the organic solvent phase, 50 parts of ion-exchanged water was dropped into the organic solvent phase over 12 minutes to allow self-dispersion (phase inversion emulsification), and the anionic micro phase was dispersed. An aqueous dispersion containing the encapsulated pigment was obtained.

Further, the solvent was distilled off by distilling the aqueous dispersion containing the microencapsulated pigment at 85 ° C., and the mixture was kept at the same temperature for 5 hours to perform a gelling treatment on the capsule wall.

The particle size of the microencapsulated pigment in the aqueous dispersion (MC-1) containing the anionic microencapsulated pigment thus obtained was measured by using UPA-150 (laser Doppler particle size distribution measurement manufactured by Nikkiso Co., Ltd.). As a result, the volume average particle diameter of the microencapsulated pigment was 146 nm, and the particles having a maximum particle diameter of 1000 nm or more were 0%. The aqueous dispersion containing the microencapsulated pigment had a nonvolatile content of 24.5%, and the content of the pigment in the microcapsules was 51.7%.

Production Example 2 (same as above) (1) Pigment kneading step In a glass bottle having a capacity of 250 ml, 15.0 parts of the resin solution (A-2) obtained in Synthesis Example 2 and dimethylethanolamine 0.1% were added.
8 parts and 15 parts of “Fastogen Blue TGR” were added, and ion-exchanged water was added so that the total amount became 75 parts. Then, zirconia beads 250 having an average particle diameter of 0.5 mm were used.
g was added and kneading was performed for 4 hours using a paint shaker. After completion of the kneading, the zirconia beads were separated by filtration to obtain a dispersion of a resin having a carboxyl group neutralized with a base and a pigment dispersed in water.

(2) Acid precipitation step Water is added to a dispersion of a resin having a carboxyl group neutralized with a base and a pigment, which is dispersed in water, and the resulting mixture is diluted twice with water. 1N hydrochloric acid was added until the resin was insolubilized and fixed to the pigment. P at this time
H was 3-5.

(3) Filtration and Rinse Steps After filtering the aqueous medium containing the pigment to which the resin was fixed by suction, the salt was washed with water to obtain a water-containing cake.

(4) Step of Neutralization and Redispersion in Aqueous Medium While stirring the hydrated cake using a disper, a 10% aqueous sodium hydroxide solution was added until the pH of the dispersion became 8.5 to 9.5. Was added. Further, after stirring was continued for 1 hour, water was added to adjust the nonvolatile content to 20%, and the aqueous dispersion containing anionic microencapsulated pigment (MC
-2) was obtained.

The particle diameter of the microencapsulated pigment in the aqueous dispersion (MC-2) containing an anionic microencapsulated pigment was measured in the same manner as in Production Example 1. As a result, the volume average particle diameter of the microencapsulated pigment was 182 nm. At 1000nm
The above particles were 0%. The content of the pigment in the microcapsules was 67%.

Production Example 3 (Production of Aqueous Dispersion Containing Magenta Anionic Microencapsulated Pigment) 23.4 parts of the resin solution (A-1) obtained in Synthesis Example 1, "Fastgen Super Magenta RTS" (CI Pigment Red 12 manufactured by Dainippon Ink and Chemicals, Inc.)
2, average particle diameter 45 nm, maximum particle diameter 100 nm) 14.2
5 parts, 0.75 part of dimethylaminomethylquinacridone as a dispersing aid, 76.9 parts of methyl ethyl ketone, 4.7 parts of "Super Beckamine L-109-60" (melamine resin manufactured by Dainippon Ink and Chemicals, Inc.) After placing 300 parts of ceramic beads having an average particle diameter of 0.5 mm in a stainless steel container, the mixture was dispersed using a bead mill disperser, and the ceramic beads were filtered off to obtain a microencapsulated pigment. Paste was prepared.

Next, 40.0 parts of the paste for microencapsulated pigment and 0.4 part of diethanolamine were placed in a polycup, and mixed using a stirrer to form an organic solvent phase. While stirring, and while irradiating the organic solvent phase with ultrasonic waves of 45 KHz, 50 parts of ion-exchanged water was dropped into the organic solvent phase over 12 minutes,
By self-dispersion (phase inversion emulsification), an aqueous dispersion containing an anionic microencapsulated pigment was obtained.

Further, the solvent was distilled off by distilling the aqueous dispersion containing the microencapsulated pigment at 85 ° C., and the mixture was kept at the same temperature for 5 hours to perform a gelling treatment on the capsule wall.

The particle size of the microencapsulated pigment in the anionic microencapsulated pigment-containing aqueous dispersion (MC-3) thus obtained was measured in the same manner as in Production Example 1. Has a volume average particle size of 1
At 43 nm, particles having a maximum particle size of 1000 nm or more were 0%. In addition, the nonvolatile content concentration of the aqueous dispersion containing the microencapsulated pigment was 23.4%, and the content of the pigment in the microcapsules was 51.7%.

Production Example 4 (Same as above) (1) Pigment Kneading Step In a glass bottle having a capacity of 250 ml, 15.0 parts of the resin solution (A-4) obtained in Synthesis Example 6 and 0.1 ml of dimethylethanolamine were added.
8 copies and "Fastgen Super Magenta RT"
S "(CI Pigment Red 122 manufactured by Dainippon Ink and Chemicals, Incorporated, average particle diameter 45 nm, maximum particle diameter 10
0 nm) 15 parts, and ion-exchanged water is added to make a total amount of 75 parts.
After adding 250 g of zirconia beads having an average particle diameter of 0.5 mm, kneading was performed for 4 hours using a paint shaker. After completion of the kneading, the zirconia beads were separated by filtration to obtain a dispersion of a resin having a carboxyl group neutralized with a base and a pigment dispersed in water.

(2) Acid precipitation step A dispersion composed of a resin having a carboxyl group and a pigment neutralized with a base and a pigment dispersed in water is diluted with water by a factor of two. Normal hydrochloric acid was added until the resin became insoluble and fixed to the pigment. PH at this time
Was 3-5.

(3) Filtration and Rinse Steps After filtering the aqueous medium containing the pigment to which the resin was fixed by suction, the salts were washed with water to obtain a water-containing cake.

(4) Neutralization and Redispersion Step in Aqueous Medium While stirring the water-containing cake using a disper, a 10% aqueous NaOH solution was added until the pH of the dispersion became 8.5 to 9.5. Was. After further stirring for 1 hour, water was added to adjust the non-volatile content to 20%, and the aqueous dispersion containing anionic microencapsulated pigment (MC-4)
I got

The particle diameter of the microencapsulated pigment in the aqueous dispersion (MC-4) containing an anionic microencapsulated pigment was measured in the same manner as in Production Example 1. As a result, the volume average particle diameter of the microencapsulated pigment was 1000 at 172 nm
Particles having a size of nm or more were 0%. The content of the pigment in the microcapsules was 67%.

Production Example 5 (same as above) 23.7 parts of the resin solution (A-7) obtained in Synthesis Example 7, "Fastgen Super Magenta RTS" (C.I. I. Pigment Red 12
2, average particle diameter 45 nm, maximum particle diameter 100 nm) 14.2
5 parts, 0.75 part of dimethylaminomethylquinacridone as a dispersing agent, 76.6 parts of methyl ethyl ketone, 4.7 parts of "Super Beckamine L-109-60" (melamine resin manufactured by Dainippon Ink and Chemicals, Inc.) After placing 300 parts of ceramic beads having an average particle diameter of 0.5 mm in a stainless steel container, the mixture was dispersed using a bead mill disperser, and the ceramic beads were filtered off to obtain a microencapsulated pigment. Paste was prepared.

Next, 40.0 parts of the above-mentioned paste for microencapsulated pigment and 0.4 part of diethanolamine were put into a polycup and mixed with a stirrer to form an organic solvent phase. While stirring, and while irradiating the organic solvent phase with ultrasonic waves of 45 KHz, 50 parts of ion-exchanged water was dropped into the organic solvent phase over 12 minutes,
By self-dispersion (phase inversion emulsification), an aqueous dispersion containing an anionic microencapsulated pigment was obtained.

Further, after distilling off the solvent by distilling the aqueous dispersion containing the microencapsulated pigment at 85 ° C., the capsule wall was gelled by keeping the same temperature for 5 hours.

The particle size of the microencapsulated pigment in the anionic microencapsulated pigment-containing aqueous dispersion (MC-5) thus obtained was measured in the same manner as in Production Example 1. As a result, the microencapsulated pigment was obtained. Has a volume average particle size of 1
At 53 nm, particles having a maximum particle size of 1000 nm or more were 0%. In addition, the nonvolatile content concentration of the microencapsulated pigment-containing aqueous dispersion was 23.9%, and the content of the pigment in the microcapsules was 51.7%.

Production Example 6 (Production of Aqueous Dispersion Containing Yellow Anionic Microencapsulated Pigment) (1) Pigment Kneading Step The resin solution (A-4) obtained in Synthesis Example 4 was placed in a glass bottle having a capacity of 250 ml. 0 parts, dimethylethanolamine 0.
8 copies and "Shimla First Yellow 8GF"
(C.I. pigment manufactured by Dainippon Ink and Chemicals, Inc.)
Yellow 17) 15 parts were added, and ion-exchanged water was added so that the total amount became 75 parts.
After adding 250 g of zirconia beads having a diameter of 250 mm, the mixture was kneaded for 4 hours using a paint shaker. After completion of the kneading, the zirconia beads were separated by filtration to obtain a dispersion of a resin having a carboxyl group neutralized with a base and a pigment dispersed in water.

(2) Acid precipitation step A dispersion of a resin having a carboxyl group and a pigment neutralized with a base and a pigment dispersed in water is diluted with water by a factor of two. Normal hydrochloric acid was added until the resin became insoluble and fixed to the pigment. PH at this time
Was 3-5.

(3) Filtration and Rinse Steps After filtering the aqueous medium containing the pigment to which the resin was fixed by suction, the salt was washed with water to obtain a water-containing cake.

(4) Neutralization and Redispersion Step in an Aqueous Medium While stirring the water-containing cake using a disper, a 10% aqueous NaOH solution was added until the pH of the dispersion became 8.5 to 9.5. Was. After stirring was further continued for 1 hour, water was added to adjust the nonvolatile content to 20% to obtain a yellow anionic microencapsulated pigment-containing aqueous dispersion (MC-6).

The particle diameter of the microencapsulated pigment in the anionic microencapsulated pigment-containing aqueous dispersion (MC-6) was measured in the same manner as in Production Example 1. As a result, the volume average particle diameter of the microencapsulated pigment was 1000 at 179 nm
Particles having a size of nm or more were 0%. The content of the pigment in the microcapsules was 67%.

Production Example 7 (Production of an aqueous dispersion containing a cyan anionic microencapsulated pigment) (1) Pigment kneading step The resin solution (A-4) obtained in Synthesis Example 4 was placed in a 250 ml glass bottle. 0 parts, dimethylethanolamine
1 part and 15 parts of "Fastogen Blue TGR" were added, and ion-exchanged water was added so that the total amount became 75 parts. Then, zirconia beads 250 having an average particle diameter of 0.5 mm were added.
After adding g, kneading was performed for 4 hours using a paint shaker. After the kneading, the zirconia beads are filtered off,
A dispersion comprising a resin having a carboxyl group neutralized with a base and a pigment and dispersed in water was obtained.

(2) Acid precipitation step A dispersion comprising a resin having a carboxyl group and a pigment neutralized with a base and a pigment dispersed in water is diluted with water by a factor of two. Normal hydrochloric acid was added until the resin became insoluble and fixed to the pigment. PH at this time
Was 3-5.

(3) Filtration and Rinse Steps After filtering the aqueous medium containing the pigment to which the resin was fixed by suction, the salt was washed with water to obtain a water-containing cake.

(4) Step of Neutralization and Redispersion in Aqueous Medium While stirring the hydrated cake using a disper, 10% of sodium hydroxide was added until the pH of the dispersion became 8.5 to 9.5. The aqueous solution was added. Further, after stirring for 1 hour,
Add water to adjust the non-volatile content to 20%,
An aqueous dispersion (MC-7) containing a blue anionic microencapsulated pigment was obtained.

The particle diameter of the microencapsulated pigment in the aqueous dispersion containing anionic microencapsulated pigment (MC-7) was measured in the same manner as in Production Example 1. As a result, the volume average particle diameter of the microencapsulated pigment was 1000 nm at 152 nm
Particles having a size of nm or more were 0%. The content of the pigment in the microcapsules was 67%.

Production Example 8 (Production of Aqueous Dispersion Containing Anionic Microencapsulated Pigment of Carbon Black with Gelled Capsule Wall) (1) Pigment Kneading Step A 1000 ml stainless steel beaker was prepared in Synthesis Example 5 15.0 parts of the resin solution (A-5), 0.8 parts of dimethylethanolamine and 15 parts of “# 960 (Mitsubishi Chemical Corporation's intermediate carbon black: average particle diameter 16 nm)” were added, and ion-exchanged water was added. Zirconia beads 500 having an average particle diameter of 0.5 mm.
After adding the parts, kneading was performed at a peripheral speed of 7.9 m / s at a temperature of 20 ° C. for 4 hours using a sand mill (manufactured by Kampe Home Paint Co., Ltd.). After completion of the kneading, the zirconia beads were separated by filtration to obtain a dispersion of a resin having a carboxyl group neutralized with a base and a pigment dispersed in water.

(2) Gelation treatment step A dispersion of a resin having a carboxyl group and a pigment neutralized with a base and a pigment dispersed in water is diluted with water by three times, and then dispersed in an autoclave. It heat-gelled at ℃.

(3) Acid precipitation step After the gelling treatment, 1N hydrochloric acid was added at room temperature while stirring with a disper until the resin was insolubilized and fixed to the pigment. The pH at this time was 3-5.

(4) Filtration and Rinse Steps After filtering the aqueous medium containing the pigment to which the resin was fixed by suction, the salt was washed with water to obtain a water-containing cake.

(5) Step of Neutralization and Redispersion in Aqueous Medium While stirring the hydrated cake using a disper, a 10% aqueous NaOH solution was added until the pH of the dispersion became 8.5 to 9.5. Was. After stirring was further continued for 1 hour, water was added to adjust the non-volatile content to 20% to obtain an aqueous dispersion (MC-8) containing an anionic microencapsulated pigment of carbon black.

The particle size of the microencapsulated pigment in the aqueous dispersion containing anionic microencapsulated pigment (MC-8) was measured in the same manner as in Production Example 1. As a result, the volume average particle diameter of the microencapsulated pigment was 1000 at 113 nm
Particles having a size of nm or more were 0%. The content of the pigment in the microcapsules was 67%.

Production Example 9 (Production of aqueous dispersion containing microencapsulated pigment by interfacial polymerization of carbon black) 400 parts of oleic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) and MA-10
0 "(Mitsubishi Chemical's medium-grade carbon black: average particle size 22 nm) 100 parts with Dyno-mill KDL-SPEC
0.5 for IAL type (Shinmaru Enterprises)
The dispersion was performed for 5 hours using zirconia beads having a diameter of mm and a filling rate of 80%. To 80 parts of this dispersion, a 10% aqueous solution of polyvinyl alcohol (polyvinyl alcohol manufactured by Tokyo Chemical Industry Co., Ltd .;
100 parts), and using a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), the number of revolutions is 12,000 rpm, and
The mixture was dispersed and emulsified under the conditions of minutes. To this emulsion, 100 parts of a 10% aqueous solution of polyvinyl alcohol and 5 parts of a 1% aqueous hydrochloric acid solution are added, and the mixture is stirred for 15 minutes.
Stirring is continued for 1 hour at 0 ° C. to condense, and the
An aqueous dispersion containing 6.5% of microencapsulated pigment (M
C-9) was obtained.

The particle diameter of the microencapsulated pigment in the microencapsulated pigment-containing aqueous dispersion (MC-9) was measured in the same manner as in Production Example 1. As a result, the volume average particle diameter of the microencapsulated pigment was 4252 nm. , 1000% or more of the particles were 80% or more. The content of the pigment in the microcapsules was 15.2%.

The aqueous dispersions containing the anionic microencapsulated pigment obtained in Production Examples 1 to 8 (MC-1) to (MC-
Table 8 below summarizes the contents of 8).

[0180]

[Table 2]

In the above table, “TGR” means “fastogen
Blue TGR ”(C.I. of Dainippon Ink and Chemicals, Inc.)
I. Pigment Blue 15) and "RTS"
Is "Fast Gen Super Magenta RTS"
(C.I. pigment manufactured by Dainippon Ink and Chemicals, Inc.)
Red 122), and “8GF” is “Shimler First Yellow 8GF” (Dainippon Ink Chemical Industry)
C.I. I. Pigment Yellow 17), and “TGR” means “Fastogen Blue TGR”
(C.I. pigment manufactured by Dainippon Ink and Chemicals, Inc.)
Blue 15), and “CB1” is “# 960”
(Mitsubishi Chemical's medium-grade carbon black, "C
"B2" represents "MA100" (Mitsubishi Chemical Corporation's intermediate carbon black, "PVA" represents a solution of polyvinyl alcohol and formalin, and "Resin dispersed base" represents an anionic group-containing organic polymer compound. Represents the base used to neutralize the anionic group of "DEA"
Represents dimethylethanolamine, "nonvolatile content" represents the nonvolatile content of the anionic microencapsulated pigment-containing aqueous dispersion, and "1000 nm>ratio" represents the anionic microencapsulated pigment-containing aqueous dispersion. The ratio of the microencapsulated pigment particles having a particle size of 1000 nm or more in the liquid is represented, and the “pigment content in the capsule” represents the content of the pigment in the microcapsules.

Example 1 An aqueous dispersion (MC-7) 3 containing an anionic microencapsulated pigment of copper phthalocyanine blue obtained in Production Example 7
To 7.5 parts, 5.0 parts of ethylene glycol, 10.0 parts of glycerin, 3.0 parts of diethanolamine, "Reodol TW-S120" (polyoxyethylene sorbitan monostearate manufactured by Kao Corporation: HLB value 14.9) 1.5
Was mixed with 43.0 parts of ion-exchanged water to prepare a cyan aqueous recording liquid having a pigment content of 5.0%.

Example 2 An aqueous dispersion (MC-1) 3 containing an anionic microencapsulated pigment of copper phthalocyanine blue obtained in Production Example 1
To 9.5 parts, 5.0 parts of ethylene glycol, 10.0 parts of glycerin, 3.0 parts of diethanolamine, "Reodol TW-L120" (polyoxyethylene sorbitan monolaurate manufactured by Kao Corporation: HLB value 16.7) 1.5 parts and 43.0 parts of ion-exchanged water were mixed to obtain a pigment content of 5.
A 0% cyan aqueous recording solution was prepared.

Example 3 An aqueous dispersion (MC-2) 3 containing an anionic microencapsulated pigment of copper phthalocyanine blue obtained in Production Example 2
To 7.5 parts, 5.0 parts of ethylene glycol, 10.0 parts of glycerin, 3.0 parts of diethanolamine, 1.5 parts of "Emulgen 147" (polyoxyethylene lauryl ether manufactured by Kao Corporation: HLB value 16.3) And 43.0 parts of ion-exchanged water to prepare a cyan aqueous recording liquid having a pigment content of 5.0%.

Example 4 To 41.3 parts of the aqueous dispersion (MC-3) containing an anionic microencapsulated pigment of magenta color obtained in Production Example 3, 5.0 parts of ethylene glycol, 10.0 parts of glycerin, and diethanolamine 3.0 parts, "Emulgen 950" (polyoxyethylene lauryl ether manufactured by Kao Corporation: HLB
(Value 18.2) 1.5 parts and ion-exchanged water 39.2 parts were mixed to prepare a magenta aqueous recording liquid having a pigment content of 5.0%.

Example 5 To 37.5 parts of the aqueous dispersion (MC-4) containing a magenta anionic microencapsulated pigment obtained in Production Example 4, 5.0 parts of ethylene glycol, 10.0 parts of glycerin, and diethanolamine 3.0 parts, "Reodol TW-S12
0 "(HLB value 14.9) 1.5 parts and ion-exchanged water 4
By mixing 3.0 parts, a magenta aqueous recording liquid having a pigment content of 5.0% was prepared.

Example 6 To 37.5 parts of the yellow anionic microencapsulated pigment-containing aqueous dispersion (MC-6) obtained in Production Example 6, 5.0 parts of ethylene glycol, 10.0 parts of glycerin, and diethanolamine 3.0 parts, "Reodol TW-S12
0 "(HLB value 14.9) 1.5 parts and ion-exchanged water 4
By mixing 3.0 parts, a yellow aqueous recording liquid having a pigment content of 5.0% was prepared.

Example 7 To 37.5 parts of the aqueous dispersion (MC-8) containing an anionic microencapsulated pigment of carbon black obtained in Production Example 8, 5.0 parts of ethylene glycol and 10.0 parts of glycerin were added.
Parts, 3.0 parts of diethanolamine, "Reodol TW-
S120 "(HLB value: 14.9) and 1.5 parts of ion-exchanged water were mixed to prepare a black aqueous recording liquid having a pigment content of 5.0%.

Example 8 Aqueous dispersion (MC-7) 3 containing an anionic microencapsulated pigment of copper phthalocyanine blue obtained in Production Example 7
To 7.5 parts, 5.0 parts of ethylene glycol, 10.0 parts of glycerin, 3.0 parts of diethanolamine, 2.0 parts of "PEREX OT-P" (sodium dialkyl sulfosuccinate, water-soluble, manufactured by Kao Corporation) and ions Exchange water 42.5
Were mixed to prepare a cyan aqueous recording liquid having a pigment content of 5.0%.

Example 9 An aqueous dispersion (MC-7) 3 containing an anionic microencapsulated pigment of copper phthalocyanine blue obtained in Production Example 7
To 7.5 parts, 5.0 parts of ethylene glycol, 10.0 parts of glycerin, 3.0 parts of diethanolamine, "Neoperex F-25" (Sodium dobesilbenzenesulfonate manufactured by Kao Corporation: water-soluble) 3.0 Was mixed with 41.5 parts of ion-exchanged water to prepare a cyan aqueous recording liquid having a pigment content of 5.0%.

In Examples 1 to 9, the aqueous recording liquid was prepared by simply mixing without using a dispersing machine such as a bead mill or a roll. And labor can be shortened, the manufacturing time can be reduced, or the energy of the dispersed energy can be saved, and the productivity can be greatly increased and the manufacturing cost can be reduced. Further, the aqueous dispersion containing anionic microencapsulated pigment used in these had a pigment content in the anionic microencapsulated pigment as high as 67%, and the pigment content in the aqueous dispersion was 13.4% or more. It is high, and other materials such as a water-soluble resin and a water-soluble organic solvent used for improving the performance as a recording liquid can be added in a considerable amount, and the versatility was high.

Next, the volume average particle diameter of the microencapsulated pigment in the cyan, magenta, yellow, and black aqueous recording liquids obtained in each of the examples was measured, and the pigments were stored for 10 days in a thermostat at 80 ° C. Are shown in Table 3.

Further, after the aqueous recording liquid obtained in each of the examples was placed in a polybin and shaken vigorously, the state of foaming was observed. The case where foaming was small was indicated by “○”, and the case where foaming was observed was indicated by “△”. It evaluated and the result was put together in the column of "foaming property" of Table 3, and was shown.

[0194]

[Table 3]

From the results shown in Table 3, the volume-average particle diameter of the anionic microencapsulated pigment in the aqueous recording liquid obtained in each Example was almost the same before and after storage, and the sedimentation of particles was further reduced. It can be seen that no storage stability and dispersion stability were found. In particular, aqueous recording liquids using sorbitan-based surfactants (“Reodol TW-S120” and “Reodol TW-L120”)
It can be understood that the viscosity is low, the generation of bubbles is small even when the recording liquid is vigorously shaken, and the recording liquid is very excellent.

Next, a bubble jet printer "BJC-400" manufactured by Canon Inc. was used by using the above recording liquid.
J ”, print the color recording image on the copy paper in the character print mode (high speed) and high definition mode (low speed), and evaluate the state of the printed image according to the following criteria. It is shown together.

(Evaluation Criteria of Printed Image) = Good printing, no non-discharge △ = Some non-discharges × = Discharge occurs, non-discharge occurs, image cannot be read.

When the nozzle filled with these aqueous recording liquids is left at room temperature for 15 days and printing is resumed, it is usually necessary to clean and then resume printing. The resolubility of the aqueous recording liquid was evaluated according to the following evaluation criteria based on the number of cleaning operations required until then, and the results are shown in Table 4.

(Evaluation Criteria for Resolubility of Aqueous Recording Liquid) = Printing is possible within 3 cleanings △ = Printing is possible in 4 to 9 cleanings × = Printing is possible in 10 or more cleanings

[0200]

[Table 4]

The aqueous recording liquid obtained in each of the examples showed no recording failure even at high speed printing, and showed a recorded image having high definition and color density, and excellent color rendering and transparency. Further, the aqueous recording liquid obtained in each of the examples is such that when the nozzle filled with the aqueous recording liquid is left at room temperature for 15 days and then used after cleaning, the number of cleanings can be less than 9 times. Was also excellent in resolubility.

Comparative Example 1 In Example 1, "Reodol TW-L106" (polyoxyethylene sorbitan monolaurate manufactured by Kao Corporation: HLB value 1) was used instead of "Reodol TW-S120".
3.6) A cyan aqueous recording liquid was prepared in the same manner as in Example 1 except that 1.5 parts of the aqueous recording liquid were used.

Comparative Example 2 A cyan aqueous recording liquid was prepared in the same manner as in Example 2, except that 1.5 parts of ion-exchanged water was used in place of "Reodol TW-S120". did.

Comparative Example 3 In Example 3, “Emulgen 147” was used instead of “Emulgen 147”.
"Emulgen 909" (polyoxyethylene sorbitan monolaurate manufactured by Kao Corporation: HLB value 12.2) 1.5
A cyan aqueous recording solution was prepared in the same manner as in Example 3 except that the parts were used.

Comparative Example 4 In Example 5, “Reodol TW-L106” (HLB value of 13.2) was used instead of “Reodol TW-S120”.
6) A magenta aqueous recording liquid was prepared in the same manner as in Example 5, except that 1.5 parts of the recording liquid were used.

Comparative Example 5 In Example 6, “Emulgen 105” (polyoxyethylene sorbitan monolaurate manufactured by Kao Corporation: HLB value: 9.7) was used instead of “Reodol TW-S120”.
A yellow aqueous recording liquid was prepared in the same manner as in Example 6, except that 1.5 parts of the aqueous recording liquid were used.

Comparative Example 6 In Example 7, “Emulgen 105” (HLB value: 9.7) 1.5 was used instead of “Reodol TW-S120”.
A black aqueous recording liquid was prepared in the same manner as in Example 7, except that the parts were used.

Comparative Example 7 To 72.1 parts of the microcapsulated pigment-containing aqueous dispersion (MC-9) of carbon black obtained in Production Example 9, 5.0 parts of ethylene glycol, 10.0 parts of glycerin, and 3.0 parts of diethanolamine were added. 0 parts, "Rheodor TW-S120"
(HLB value 14.9) 1.5 parts and ion-exchanged water 8.4
Were mixed to prepare a black aqueous recording liquid having a pigment content of 4.0%.

Using the aqueous recording liquids obtained in Comparative Examples 1 to 7,
In the same manner as in the example, the state of the printed image and the re-solubility of the aqueous recording liquid were evaluated. The results are shown in Table 5.

[0210]

[Table 5]

Using the aqueous recording liquids obtained in Comparative Examples 1 to 7,
Bubble jet printer "BJ" manufactured by Canon
Using C-400J, a color recorded image was printed at high speed on copy paper. These aqueous recording liquids, when high-speed printing is performed, non-discharge of the liquid is seen, showing a blurred recorded image,
It could not be used as is.

When the nozzles filled with the aqueous recording liquids of Comparative Examples 1 to 7 were allowed to stand at room temperature for 15 days, and then used after cleaning, the cleaning frequency was reduced except for the aqueous recording liquids obtained in Comparative Examples 1 and 2. And the resolubility was poor.

[0213]

The aqueous recording liquid of the present invention is excellent in pigment dispersibility and storage stability, so that it has high definition and color density, excellent color rendering properties and transparency, and is capable of saving labor in the dispersion process. The manufacturing cost can be reduced, and the cost of the recording liquid can be reduced.

Further, the aqueous recording liquid of the present invention is excellent in re-dissolving property and therefore highly reliable. In particular, in high-speed printing of a thermal inkjet printer, no non-discharge of the aqueous recording liquid was observed. Shows stable ejection.

Claims (8)

[Claims] 1. An anionic microencapsulated pigment obtained by coating (1) an organic pigment or carbon black with an organic polymer compound containing an anionic group neutralized with a base, and (2) a water-soluble pigment. An aqueous recording liquid containing an anionic surfactant and / or a nonionic surfactant having an HLB value of 14 or more, wherein the content of the organic pigment or carbon black in the anionic microencapsulated pigment is 35 or less.
Aqueous recording liquid characterized in that the amount is from about 80% by weight. 2. The aqueous recording liquid according to claim 1, wherein the organic polymer containing an anionic group neutralized with a base is an organic polymer containing a carboxyl group neutralized with a base. . 3. The aqueous recording liquid according to claim 2, wherein the water-soluble anionic surfactant and / or the nonionic surfactant having an HLB value of 14 or more is a sorbitan surfactant. 4. An organic polymer compound containing an anionic group neutralized with a base, having an acid value of 30 to 150 KOH mg.
The aqueous recording liquid according to claim 2 or 3, wherein a carboxyl group of an acrylic resin having a number average molecular weight of 2,000 to 20,000 is neutralized with a base. 5. An organic polymer compound containing an anionic group neutralized with a base, having a glass transition temperature of -20 to 4
The aqueous recording liquid according to claim 4, which is an acrylic resin in a temperature range of 0 ° C. 6. The maximum particle size of the anionic microencapsulated pigment is 1000 nm or less, the average particle size is 300 nm or less, and the maximum particle size of the organic pigment or carbon black is 200 nm or less, and the average particle size of the primary particles is 10-1
The aqueous recording liquid according to any one of claims 2 to 5, which is in a range of 00 nm. 7. An anionic microencapsulated pigment,
A mixture containing an anionic organic polymer compound having self-dispersibility in water and a pigment is used as an organic solvent phase, and water is added to the organic solvent phase, or the organic solvent phase is added to water. And self-dispersion (phase inversion emulsification), or by neutralizing a part or all of the anionic groups of organic polymer compounds containing anionic groups with a basic compound to obtain water. After imparting dissolving power to the pigment and kneading the pigment in an aqueous medium, the pH is neutralized or acidified with an acidic compound to precipitate organic acid compounds containing an anionic group (acid precipitation) to form a pigment. 7. A water-containing cake obtained by a method of fixing, which is obtained by neutralizing and dispersing a part or all of anionic groups using a basic compound and dispersing the same.
Aqueous recording liquid according to any one of the above. 8. The aqueous recording liquid according to claim 1, which is used for an ink jet printer.