JP2003253151A - Pigment composition, water-based pigment dispersion and water-based pigment recording liquid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a quinacridone pigment composition exhibiting coloring power without detriment to a hue when added for coloring to a medium to be colored such as resin. <P>SOLUTION: The pigment composition comprises a quinacridone pigment and at least 0.01-0.1 pt.mass of carbon black based on 100 pts.mass of the quinacridone pigment. Preferably, the pigment composition comprises a microcapsulated pigment where at least carbon black and the quinacridone pigment are present in the above ratio and simultaneously covered with an anionic group-containing organic polymer compound. The water-based pigment dispersion and the water-based pigment recording liquid each comprise the pigment composition. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a pigment composition, an aqueous pigment dispersion and an aqueous pigment recording liquid.

[0002]

2. Description of the Related Art Hitherto, dyes have been used as coloring materials in writing instruments such as felt-tip pens and water-based markers, and in inks for inkjet printers. Although the recording liquid using the dye is excellent in coloring power, it has problems in light resistance and water resistance.

In recent years, in order to solve these problems, conversion of a coloring material from a dye to a pigment has been studied in the above-mentioned field of use. In order to use a pigment as a coloring material in this field, particularly in the field of aqueous recording liquid for inkjet, a very high level of dispersibility and dispersion stability in a pigment dispersion which is a solid-liquid two-phase system is required. There is. As means for achieving such a high degree of dispersibility and dispersion stability, an aqueous pigment dispersion containing a microencapsulated pigment obtained by coating a pigment with an anionic group-containing organic polymer compound is disclosed in JP-A-9-151342. Is disclosed. It is also described that a quinacridone pigment can be used as a red organic pigment for that purpose.

[0004]

However, the red water-based pigment dispersion containing the microencapsulated pigment described in JP-A-9-151342 and the like, and the red water-based pigment recording liquid obtained by using the same are also quinacridone. In some cases, the use of a system pigment is not sufficiently satisfactory in terms of tinting strength. Further, as disclosed in JP-A-2000-191974, even if a quinacridone-based pigment is used in combination with a sulfonic acid derivative or the like corresponding thereto, the effect of improving the coloring power without impairing the hue is small.

[0005]

DISCLOSURE OF THE INVENTION As a result of intensive studies in view of the above situation, the present inventors have found that quinacridone pigments are added in an amount of 0.01 to 0.
By including 1 part by mass of carbon black,
Surprisingly, they have found that a high tinting strength can be obtained without impairing the hue, and have completed the present invention.

That is, the present invention provides a quinacridone pigment and at least 0.01 per 100 parts by weight of a quinacridone pigment.
To 0.1 parts by mass of carbon black, a quinacridone pigment and at least 0.01 to 0.1 parts by mass per 100 parts by mass of the quinacridone pigment.
An aqueous pigment dispersion containing 1 part by mass of carbon black, at least 0.01 to 0.1 per 100 parts by mass of a quinacridone pigment and a quinacridone pigment.
The present invention provides an aqueous pigment recording liquid characterized by containing parts by mass of carbon black.

[0007]

The present invention will be described in detail below. The pigment composition of the present invention is characterized by containing a quinacridone pigment and a specific amount of carbon black.

The quinacridone pigment in the present invention is, for example, C.I. I. Pigment Violet 19 (unsubstituted quinacridone), Red 122 (2,9-dimethylquinacridone pigment), Red 209 (3,10).
-Dichloroquinacridone pigment), Red 202
(2,9-dichloroquinacridone pigment), Red 2
No. 07 (unsubstituted quinacridone-4,11-dichloroquinacridone solid solution pigment), the same Red 206 (unsubstituted quinacridone-unsubstituted quinacridone quinone solid solution pigment), an unsubstituted quinacridone pigment, a dialkylquinacridone pigment, a halogenoquinacridone pigment, and these. Of a solid solution pigment.

These quinacridone pigments are conventionally known methods, for example, British Patent No. 1002641, US Pat. No. 3,257,405, Japanese Patent Publication No. 37-2879, Japanese Patent Publication No. 40-7780, US Pat.
JP-B-45-29755, JP-B-55-8102
Japanese Patent Laid-Open No. 60-38470, Japanese Patent Laid-Open No. 6-8
It can be produced by the method described in JP-A-8899, JP-A-7-216255 and the like.

As the carbon black in the present invention, known and commonly used ones can be used, but any carbon black such as acidic carbon, neutral carbon, self-dispersion type carbon and the like can be used. Specifically, it is preferable to select a material that can be used for paints and inks, does not cause sedimentation when formed into a dispersion, and does not impair properties such as nozzle clogging when processed into an aqueous recording liquid.

The amount of carbon black used in preparing the pigment composition of the present invention is preferably 0.01 to 0.1 part by mass, and more preferably 0.02 to 0.08 part, per 100 parts by mass of the quinacridone pigment. Parts by mass are preferred. If the added amount is too small, the expected coloring power due to the combined use is difficult to be expressed, and if the added amount is too large, adverse effects such as a change in hue and a decrease in saturation appear.

The pigment composition of the present invention can be prepared by mixing the quinacridone pigment and carbon black as essential components.

Carbon black can be added to the quinacridone-based pigment at any stage during preparation of the above-mentioned pigment composition, preparation of an aqueous pigment dispersion described later, and preparation of an aqueous pigment recording liquid described later. It is preferably added at the time of producing the above-mentioned pigment composition or at the time of producing an aqueous pigment dispersion described later. Among them, in the case of adding carbon black to the quinacridone-based pigment during the preparation of the pigment composition, rather than mixing the quinacridone-based pigment and the carbon black, which have been separately prepared in advance, the raw material for producing the quinacridone-based pigment is particularly preferable. Carbon black is preferably added during the dehydration condensation cyclization reaction or during the subsequent pigmentation.

The pigment composition of the present invention preferably further contains a halogenoquinacridone sulfonic acid derivative in addition to the quinacridone pigment and carbon black. When the halogenoquinacridone sulfonic acid derivative is used in combination with the quinacridone pigment, the fluidity and dispersibility of the quinacridone pigment can be improved.

The halogenoquinacridone sulfonic acid derivative in the present invention comprises a halogenoquinacridone compound having a sulfonic acid group, a metal sulfonate group or an ammonium sulfonate group as a functional group. As the halogenoquinacridonesulfonic acid derivative, a dihalogenoquinacridonesulfonic acid derivative is preferable. The quinacridone sulfonic acid derivative is composed of the corresponding quinacridone monosulfonic acid derivative, quinacridone disulfonic acid derivative and the like. These can be synthesized, for example, by reacting dihalogenoquinacridone with concentrated sulfuric acid by a known method to introduce a sulfonic acid group, and then, if necessary, forming a salt by a known method.

Examples of such halogenoquinacridone sulfonic acid derivatives include dichloroquinacridone monosulfonic acid derivatives, dichloroquinacridone disulfonic acid derivatives, dibromoquinacridone monosulfonic acid derivatives, dibromoquinacridone disulfonic acid derivatives and the like.
Examples of the substitution position on the quinacridone skeleton of two halogen atoms composed of chlorine atom or bromine atom include a combination of 2-position and 9-position, a combination of 3-position and 10-position, a combination of 4-position and 11-position, and the like. As the metal forming the sulfonic acid metal salt, monovalent metals such as sodium and potassium, divalent metals such as magnesium, calcium, barium and strontium, trivalent metals such as aluminum, iron and cobalt,
Transition metals such as nickel, copper and zinc may be mentioned. Furthermore,
As the substance that forms ammonium sulfonate, decylamine, dodecylamine, octadecylamine, ethanolamine, diethanolamine, in addition to ammonia,
Organic amines such as triethanolamine, triethylamine, tetraethylammonium, tetrabutylammonium, didodecyldimethylammonium and the like can be mentioned.

These halogenoquinacridone sulfonic acid derivatives can be used in any of the same manner as in the case of carbon black during the preparation of the above-mentioned pigment composition, the preparation of the aqueous pigment dispersion described later, and the preparation of the aqueous pigment recording liquid described later. Although it can be added to the quinacridone-based pigment at the stage, it is preferably added at the time of producing the above-mentioned pigment composition or at the time of producing an aqueous pigment dispersion described later. Among them, in the case of adding the halogenoquinacridone sulfonic acid derivative to the quinacridone pigment during the preparation of the pigment composition, rather than mixing the quinacridone pigment and the halogenoquinacridone sulfonic acid derivative which have been separately prepared in advance, a quinacridone pigment is particularly preferable. It is preferably added during the dehydration condensation cyclization reaction of the raw materials during the production or during the subsequent pigmentation. Although the detailed reason for this is not clear, it is considered that the halogenoquinacridone sulfonic acid derivative and the quinacridone-based pigment interact more strongly when added to the quinacridone-based pigment during the preparation of the above-described pigment composition.

The amount of the halogenoquinacridone sulfonic acid derivative used is 1 with respect to 100 parts by mass of the quinacridone pigment.
It is preferable to be in the range of
It is preferably in the range of 16 parts by mass. If the amount used is too small, the effect of combined use is difficult to be exhibited, and if the amount is too large, adverse effects such as hue change, saturation reduction, and bleeding during recording may appear.

To prepare the pigment composition of the present invention, carbon black can be added at any stage of the quinacridone pigment production. For example, it can be mixed with the raw material of the quinacridone pigment, or can be added during the dehydration condensation reaction. It can be added at the time of pigmentation,
It can also be added to the slurry after pigmentation. It is also possible to mix the quinacridone pigment and carbon black in powder form.

Similarly, the halogenoquinacridone sulfonic acid derivative can be added at any stage of the quinacridone pigment production. For example, it can be mixed with the raw material of the quinacridone pigment, or can be added during the dehydration condensation reaction. It can be added at the time of pigmentation, or can be added to the slurry after pigmentation. Although not preferred, it is also possible to mix the quinacridone pigment and the halogenoquinacridone sulfonic acid derivative in powder form.

The carbon black and the halogenoquinacridone sulfonic acid derivative can be added simultaneously or separately.

If necessary, the pigment composition of the present invention is subjected to a known and conventional post-treatment such as a solvent method or a solvent salt milling method to obtain a pigment composition having a finer particle size distribution. Can be done.

Needless to say, various other conventional quinacridone pigment derivatives containing no sulfonic acid group or sulfonic acid salt as a functional group alone or with a halogenoquinacridone sulfonic acid derivative are added to the pigment crude product containing carbon black in the present invention. They can be added together. When added to the pigment composition containing the carbon black of the present invention, the one which can most improve the viscosity stability is the quinacridone pigment derivative containing a phthalimidoalkyl group.

The pigment composition of the present invention thus obtained is
It can be used for publicly known and commonly used purposes, for example, production of printing inks, paints, colored molded products, toners for electrostatic image development, inks for inkjet recording, liquid crystal color filters and the like. The content of the pigment composition of the present invention contained in a medium to be colored (a medium to be colored) such as a resin is preferably 0.1 to 40 parts by weight per 100 parts of the medium to be colored.

The aqueous pigment dispersion of the present invention is characterized by containing a quinacridone pigment and at least 0.01 to 0.1 part by mass of carbon black per 100 parts by mass of the quinacridone pigment.

The aqueous pigment dispersion of the present invention can be prepared, for example, by dispersing the pigment composition of the present invention obtained as described above together with a film-forming resin in an aqueous medium. . The quinacridone pigment and the quinacridone pigment 1 are prepared without preparing the pigment composition of the present invention in advance.
An aqueous pigment dispersion is prepared by adding at least 0.01 to 0.1 part by mass of carbon black per 00 parts by mass as an essential component, and optionally a halogenoquinacridone sulfonic acid derivative in an aqueous medium at the same time. You can also do it.

The aqueous pigment dispersion of the present invention comprises, for example, the above-mentioned pigment composition of the present invention, together with a desired additive such as a dispersant, an anionic group-containing organic polymer compound, or a base, and various known dispersions. It can be produced by dispersing in an aqueous medium using an apparatus. Further, in the presence or absence of a halogenoquinacridone derivative, after separately producing a quinacridone-based aqueous pigment dispersion containing no carbon black and a carbon black aqueous pigment dispersion,
It is also possible to mix these to prepare an aqueous pigment dispersion containing carbon black. When these aqueous pigment dispersions are dispersed together with an anionic group-containing organic polymer compound, it is possible to obtain an aqueous pigment dispersion that is more excellent in dispersion level and dispersion stability.

At least the quinacridone-based pigment contained in the aqueous pigment dispersion is present together with the anionic group-containing organic polymer compound, rather than the anionic group-containing organic polymer compound. However, above all, it is preferable that not only the quinacridone pigment but also the carbon black is similarly coated with the anionic group-containing organic polymer compound. The optimum case is when all of the quinacridone pigment, carbon black, and the halogenoquinacridone sulfonic acid derivative are coated with an anionic group-containing organic polymer compound.

The anionic group-containing organic polymer compound used in the aqueous pigment dispersion of the present invention is not particularly limited as long as it has an anionic group. For example, a carboxyl group, a sulfone group, a phospho group, Anionic group-containing organic polymer compounds obtained by copolymerizing an anionic group-containing monomer containing a thiocarboxyl group and other monomers copolymerizable with these anionic group-containing monomers are mentioned. Considering availability, price, etc., anionic group-containing organic polymer compounds containing a carboxyl group or a sulfone group are preferable, and a carboxyl group can be widely controlled in the coexistence range of an electrically neutral state and an anionic state. An anionic group-containing organic polymer compound containing is particularly preferable.

The anionic group-containing organic polymer compound used in the aqueous pigment dispersion of the present invention includes, for example, an anionic group-containing organic polymer compound which may have a crosslinked portion.

Typically, an acrylic acid ester-based polymer having an anionic group having a crosslinked portion, an acrylic acid ester-based polymer having an anionic group having no crosslinking portion, and an anionic group having a crosslinked portion There are methacrylic acid ester-based polymers and methacrylic acid ester-based polymers having an anionic group having no cross-linked portion. In the present invention, both (meth) acrylic acid ester are referred to as (meth) acrylic acid ester by including both acrylic acid ester and methacrylic acid ester. The (meth) acrylic acid ester-based polymer means a polymer obtained by polymerizing a (meth) acrylic acid ester as a main component.

The most suitable anionic group-containing organic polymer compound is an anionic group-containing organic polymer compound in which the anionic group contains both a carboxyl group and a carboxylate group.

Examples of the monomer containing a carboxyl group include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid and 4-vinylbenzoic acid; vinyl succinate, allyl maleate. , Polybasic acid unsaturated esters such as vinyl terephthalate and allyl trimellitate. Examples of the monomer having a sulfonic acid group include unsaturated carboxylic acid sulfo-substituted alkyl or aryl esters such as 2-sulfoethyl acrylate and 4-sulfophenyl methacrylate; sulfocarboxylic acid unsaturated esters such as vinyl sulfosuccinate. Sulfostyrenes such as styrene-4-sulfonic acid may be mentioned.

Examples of other monomers that can be copolymerized with the anionic group-containing monomer include the following.

Methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n- (meth) acrylate
Butyl, isobutyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate,
Cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate.

2,3-epoxypropyl (meth) acrylate, 2,3-epoxybutyl (meth) acrylate,
2,3-epoxycyclohexyl (meth) acrylate,
Vinyl (meth) acrylate, dimethyl maleate, diethyl maleate, dimethyl fumarate, diethyl fumarate, ethyl itaconate, benzyl itaconate, (meth)
2-hydroxyethyl acrylate, 2-hydroxypropyl (meth) acrylate, 2-aminoethyl (meth) acrylate, 2-aminopropyl (meth) acrylate, 3-aminopropyl acrylate, (meth) acrylic acid 2 −
(Methylamino) ethyl, 2- (methylamino) propyl (meth) acrylate, 2- (ethylamino) ethyl (meth) acrylate, 2- (ethylamino) propyl (meth) acrylate, (meth) acrylic acid Unsaturated fatty acid esters such as 2- (dimethylamino) ethyl and 3- (dimethylamino) propyl (meth) acrylate.

(Meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-propyl (meth) acrylamide, N-dimethyl (meth) acrylamide, N-diethyl (meth) acrylamide, N- Dipropyl (meth) acrylamide,
N- (2-aminoethyl) (meth) acrylamide, N
-(2-aminopropyl) (meth) acrylamide, N
-(3-aminopropyl) (meth) acrylamide, N
-[2- (Methylamino) ethyl] (meth) acrylamide, N- [2- (methylamino) propyl] (meth)
Acrylamide, N- [3- (methylamino) propyl] (meth) acrylamide, N- [2- (dimethylamino) ethyl] (meth) acrylamide, N- [2-
(Dimethylamino) propyl] (meth) acrylamide, N- [3- (dimethylamino) propyl] (meth)
Unsaturated fatty acid amides such as acrylamide, maleamide, N, N-dimethylmaleamide, fumaramide, N, N-dimethylfumaramide.

Acrylonitrile, methacrylonitrile,
Unsaturated nitriles such as vinyl acetate, vinyl propionate, vinyl butanoate, vinyl hexanoate, vinyl 2-ethylhexanoate, vinyl octadecanoate, vinyl benzoate, allyl acetate, allyl propionate, allyl hexanoate, decanoic acid Unsaturated carboxylic acid esters such as allyl; unsaturated ethers such as ethyl vinyl ether, butyl vinyl ether; styrene, α-methylstyrene,
Styrenes such as o-methylstyrene, m-methylstyrene, p-methylstyrene, p-t-butylstyrene, 4-methoxystyrene, 4-chlorostyrene; ethylene,
Unsaturated hydrocarbons such as propylene, 1-butene, 1-octene, vinylcyclohexane and 4-vinylcyclohexene; unsaturated halogenated hydrocarbons such as vinyl chloride, vinylidene chloride, tetrafluoroethylene and 3-chloropropylene. 4-vinylpyridine, N-vinylcarbazole, N-vinylpyrrolidone, and other vinyl-substituted heterocyclic compounds.

Reaction products of a monomer containing a substituent having an active hydrogen such as a carboxyl group, a hydroxyl group and an amino group in the above-exemplified monomers with epoxides such as ethylene oxide, propylene oxide and cyclohexene oxide;
Examples thereof include reaction products of a monomer containing a substituent having a hydroxyl group, an amino group, etc. in the above-exemplified monomers and a carboxylic acid such as acetic acid, propionic acid, butanoic acid, hexanoic acid, decanoic acid, dodecanoic acid.

The anionic group-containing organic polymer compound can be synthesized by various conventionally known reaction methods such as bulk polymerization, solution polymerization, suspension polymerization and emulsion polymerization.

The weight average molecular weight of the anionic group-containing organic polymer compound used in the present invention is 2,000 to 100,
It is preferably in the range of 5,000, and 5,000 to 5
It is particularly preferable that it is in the range of 10,000. If the weight average molecular weight is too small, the dispersion stability of the aqueous pigment dispersion itself is lowered, and if it is too large, not only the viscosity of the dispersion becomes high but also the dispersibility tends to be lowered. Further, when the weight average molecular weight is too small or too large, when it is applied to an ink for an inkjet printer, for example, it adversely affects printing characteristics, and it becomes difficult to perform stable printing for a long period of time.

The acid value and glass transition point of the anionic group-containing organic polymer compound used in the present invention are preferably in the ranges of 30 to 220 mgKOH / g and -20 to 60 ° C., respectively. If the acid value is too low, the dispersibility and dispersion stability of the aqueous pigment dispersion will deteriorate, and the printing stability when applied to ink for inkjet printers will deteriorate. If the acid value is too high, the water resistance of the image will deteriorate when applied to an ink for inkjet printers. If the glass transition point is too high, it is difficult to obtain stable printing, and if it is too low, the image storability such as abrasion resistance and sticking resistance tends to be deteriorated.

The anionic group-containing organic polymer compound in the aqueous pigment dispersion of the present invention has a form in which at least part of the anionic group is ionized by a basic substance, dispersibility and dispersion stability. Is preferable for the expression of The optimum proportion of ionized groups among the anionic groups is determined by the composition of the anionic group-containing organic polymer compound used,
Although it is not uniquely limited because it varies depending on the molecular weight, the acid value, etc., it may be in the range in which desired dispersibility and dispersion stability are expressed, and usually 30 to 100%, particularly 70 to
It is preferably set in the range of 100%. This proportion of ionized groups does not mean the molar ratio of anionic groups to basic substances, but takes dissociation equilibrium into account. For example, when the anionic group is a carboxyl group, the ratio of groups ionized by dissociation equilibrium is less than 100% even if a stoichiometrically equivalent amount of a strong basic substance is used. It is in a mixed state.

As described above, as the basic substance used in the anionic group-containing organic polymer compound for ionizing at least a part of the anionic group, there may be mentioned known and conventional ones. Preferred examples include compounds selected from the group consisting of primary, secondary or tertiary organic amines (including basic nitrogen-containing heterocyclic compounds) and alkali metal hydroxides. By ionizing at least a part of the anionic group with these exemplified suitable basic substances, the counterion of the carboxylate group is an ammonium ion (including a protonated cation of a basic nitrogen-containing heterocyclic compound), an alkali ion. It becomes a cation selected from the group consisting of metal ions.

In the present invention, a pigment containing at least a quinacridone pigment and carbon black will be simply referred to as a pigment hereinafter. Therefore, hereinafter, those containing a quinacridone pigment, carbon black, and a halogenoquinacridone sulfonic acid derivative are also included in the definition of this pigment.

The ratio of the pigment to the anionic group-containing organic polymer compound in the aqueous pigment dispersion of the present invention is 10 to 2 of the anionic group-containing organic polymer compound to 100 parts by mass of the pigment.
About 100 parts by mass is preferable. If the ratio of the anionic group-containing organic polymer compound is too low, the friction resistance when used as an aqueous recording liquid decreases, and if it is too high, the viscosity becomes high when the water-based recording liquid is adjusted. There is a tendency.

The aqueous pigment dispersion of the present invention can be produced by a process including a step of dispersing a mixture of at least a pigment, an anionic group-containing organic polymer compound, a basic substance and water.

Examples of the steps other than the dispersing step that can be incorporated into the process for producing the aqueous pigment dispersion of the present invention include a pre-dispersing step, a dissolving step, a diluting step, a distillation step, a centrifugation step, an acid precipitation step, a filtration step, Redispersion step, pH adjustment step,
Examples include a filling step.

Examples of the pre-dispersing step include a step of mixing and dispersing a resin in a solution state or a molten state and a pigment to obtain a slurry state, a paste state or a master batch or a solid state called a chip. Examples of the dissolving step include a step of dissolving a solid anionic group-containing organic polymer compound in an organic solvent, preferably a water-soluble organic solvent, or an aqueous medium containing a basic substance, or an anionic group-containing organic compound. There is a step of dissolving a water-soluble organic solvent solution of a polymer compound in an aqueous medium containing a basic substance.

In the present invention, a step of dispersing a mixture of a pigment, an anionic group-containing organic polymer compound, a basic substance and water is essential. It is preferable to include a water-soluble organic solvent in this mixture. More specifically, it is preferable to include a step of dispersing at least a mixture of a pigment, an anionic group-containing organic polymer compound, a basic substance, a water-soluble organic solvent and water.

In the aqueous dispersion of the present invention, in order to exhibit more excellent properties in all of the ultimate dispersion level, the time required for dispersion, and the dispersion stability, the pigment may be mixed with an anionic group-containing organic polymer compound. It is preferred to disperse the coated encapsulated pigment in an aqueous dispersion. In order to form such a state, the pigment is dispersed in the liquid medium containing the anionic group-containing organic polymer compound, and as a subsequent step, the anionic group-containing organic polymer in a dissolved state is used as the subsequent step. It is preferred to incorporate a step of coating the pigment with the compound.

In the step of coating the pigment with the anionic group-containing organic polymer compound in a dissolved state, the anionic group-containing organic polymer compound dissolved in the alkaline aqueous solution is precipitated by acidifying the solution. The step of allowing is preferred.

Examples of the distillation step include a step of removing the organic solvent used in the dispersing step, a step of removing excess water to obtain a desired solid content concentration, and the like. An example of the centrifugation step is a step of removing coarse particles in the dispersion, which adversely affects the suitability for use as an aqueous recording liquid.

As an example of the acid precipitation step, the aqueous dispersion obtained in the dispersion step is acidified by adding an acid such as hydrochloric acid, sulfuric acid or acetic acid,
There is a step of depositing an anionic group-containing organic polymer compound on the surface of pigment particles. This step can enhance the interaction between the pigment and the anionic group-containing organic polymer compound. Examples of the filtration step include a step of removing coarse particles in the dispersion by a cartridge filter or a membrane filter as in the centrifugal separation step, a filter press, a Nutsche type filtration device, and a pressure filtration of the solid content after the above-mentioned acid precipitation step. There is a step of filtering with a device or the like. An example of the redispersion step is a step of adding a basic substance and, if necessary, water and additives to the solid content obtained by the acid precipitation step and the filtration step to make a dispersion again. Thereby, the counterion of the ionized anionic group in the anionic group-containing organic polymer compound can be changed from that used in the dispersion step.

In the dispersion step, a water-soluble organic solvent may be used in combination, which may reduce the liquid viscosity in the dispersion step. Examples of the water-soluble organic solvent include acetone, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, and other ketones; methanol, ethanol, 2-propanol, 2-methyl-1-propanol, 1-butanol, 2-methoxyethanol, Alcohols such as tetrahydrofuran;
Ethers such as 1,4-dioxane and 1,2-dimethoxyethane; amides such as dimethylformamide, N-methylpyrrolidone and 2-pyrrolidone. These water-soluble organic solvents may be used as an anionic group-containing organic polymer compound solution, or may be separately and separately added to the dispersion mixture.

As a dispersing device that can be used in the dispersing step, various known devices can be used, and the dispersing device is not particularly limited, and examples thereof include steel, stainless steel, zirconia, alumina, silicon nitride,
Method of using kinetic energy of spherical dispersion medium made of glass or the like having a diameter of about 0.1 to 10 mm, method of utilizing shearing force by mechanical stirring, pressure change of distributed physical distribution bundle supplied at high speed, flow path It is possible to adopt a distributed method such as a method that uses a force generated by a change or a collision.

As described above, in the present invention, as the anionic-containing organic polymer compound, an anionic-containing organic polymer compound having a crosslinked portion can be used.
However, in the application of the aqueous recording liquid described below, a high degree of dispersion stability is often required, and crosslinking should be completed in advance, and crosslinked during transportation, storage, and actual use (recording). It is preferable to prevent the reaction from occurring.

In the present invention, when the anionic group-containing organic polymer compound contains a crosslinkable group, for example, at least one or more of unsaturated fatty acids having an epoxy group such as 2,3-epoxypropyl acrylate described above. In the case of a copolymer containing a monomer consisting of, a ring-opening reaction and cross-linking can be carried out at any stage after the dispersion step in the aqueous dispersion production process. Ring-opening reaction temperature is 8
About 0 to 140 ° C is preferable. If the reaction temperature is too low, the reaction rate is slow, and it takes a long time to complete the reaction.
Pigment particles are easily fused to form an aggregate. If the reaction temperature is too high, fusion between the pigment particles and growth of the pigment particles themselves occur, which is not preferable in any case. If the reaction temperature is higher than the boiling point of the dispersion, it is necessary to use a pressure reactor.

The aqueous pigment dispersion of the present invention comprises a quinacridone-based pigment, carbon black, a halogenoquinacridone sulfonic acid derivative, another quinacridone-based pigment derivative, or at least a quinacridone-based pigment of the organic polymer compound containing an anionic group. It is preferable that the total content of the dispersed particles of the coated microencapsulated pigment is adjusted to 10 to 30% in terms of mass. The aqueous pigment dispersion of the present invention obtained as described above, if necessary, by adding a binder resin, a curing agent, etc., to a known and commonly used field of application, for example, an aqueous printing ink or an aqueous paint. You can

The aqueous pigment recording liquid of the present invention is an aqueous pigment recording liquid containing a quinacridone pigment and at least 0.01 to 0.1 part by mass of carbon black as an essential component per 100 parts by mass of the quinacridone pigment. The aqueous pigment recording liquid is preferably prepared so that the total content of the dispersed particles in the nonvolatile content is 1 to 8% in terms of mass.

The aqueous pigment recording liquid of the present invention can be prepared by mixing, for example, a water-soluble organic solvent or water with the above-mentioned aqueous pigment dispersion containing dispersed particles having a higher nonvolatile content, or carbon black. And a quinacridone-based aqueous pigment dispersion which may contain a halogenoquinacridone sulfonic acid derivative containing no carbon black aqueous pigment dispersion,
For example, it can be prepared by mixing a water-soluble organic solvent, water and the like. In the presence or absence of a halogenoquinacridone derivative, a quinacridone-based aqueous pigment recording liquid containing no carbon black and a carbon black aqueous pigment recording liquid are separately prepared, and then mixed to prepare an aqueous pigment containing carbon black. It is also possible to adjust the recording liquid.

If necessary, these aqueous pigment recording liquids include, for example, surfactants, antifoaming agents, antioxidants, water-soluble resins, preservatives, viscosity adjusting agents, pH adjusting agents, chelating agents, and drying agents. Known and commonly used additives such as an inhibitor can also be added.

As the water-soluble organic solvent that can be used for preparing the recording liquid, for example, methanol, ethanol,
1-propanol, 2-propanol, 2-methyl-1
-Propanol, 1-butanol, 2-methoxyethanol, 2-butoxyethanol, 2- (2-methoxyethoxy) ethanol, 2- (2-butoxyethoxy) ethanol, 2- [2- (2-methoxyethoxy) ethoxy] Ethanol, 2- [2- (2-butoxyethoxy)
Alcohols such as ethoxy] ethanol; 1,2-ethanediol, 1,2-propanediol, 1,2-butanediol, 2,3-butanediol, 2,2′-oxybisethanol, 2,2′- Ethylenedioxybis (ethanol), thiodiethanol, glycerin, 1,
Polyhydric alcohols such as 2,6-hexanetriol; dimethylformamide, dimethylacetamide, N-methyl-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-
Amides such as 2-imidazolidinone; Ketones such as acetone, methyl ethyl ketone, methyl n-butyl ketone, methyl isobutyl ketone; tetrahydrofuran, 1,4
-Dioxane, 1,2-dimethoxyethane, 1,2-diethoxyethane, 2,2'-oxybis (2-methoxyethane), 2,2'-oxybis (2-ethoxyethane), 2,2'-ethylene Ethers such as dioxybis (2-methoxyethane) and 2,2′-ethylenedioxybis (2-methoxyethane) can be mentioned. The content ratio of the water-soluble organic solvent in the recording liquid is preferably 50% by mass or less, particularly preferably 5 to 40% by mass.

Surfactants that can be added to the recording liquid of the present invention include anionic, cationic, zwitterionic,
Any of nonionic may be used.

Examples of the anionic surfactant include:
Fatty acid salts such as sodium stearate, potassium oleate, and semi-hardened tallow fatty acid sodium; alkyl sulfate ester salts such as sodium dodecyl sulfate, tri (2-hydroxyethyl) ammonium dodecyl sulfate and sodium octadecyl sulfate; sodium nonylbenzenesulfonate, Benzene sulfonates such as sodium dodecylbenzene sulfonate, sodium octadecyl benzene sulfonate, sodium dodecyl diphenyl ether disulfonate; naphthalene sulfonates such as sodium dodecyl naphthalene sulfonate, naphthalene sulfonic acid formalin condensate; sodium dodecyl sulfosuccinate, sulfosuccinic acid Acid salts of sulfosuccinate such as sodium dioctadecyl; polyoxyethylene dodecyl ether sulfate Lithium, polyoxyethylene dodecyl ether sulfate tri (2-hydroxyethyl) ammonium sulfate, sodium polyoxyethylene octadecyl ether sulfate, sodium polyoxyethylene dodecylphenyl ether sulfate, and other polyoxyethylene sulfate salts; potassium dodecyl phosphate, sodium octadecyl phosphate And the like.

As the cationic surfactant, for example,
Alkyl amine salts such as octadecyl ammonium acetate and coconut oil amine acetate; quaternary ammonium salts such as dodecyl trimethyl ammonium chloride, octadecyl trimethyl ammonium chloride, dioctadecyl dimethyl ammonium chloride and dodecyl benzyl dimethyl ammonium chloride.

Examples of the zwitterionic activator include alkylbetaines such as dodecylbetaine and octadecylbetaine; amine oxides such as dodecyldimethylamine oxide.

Examples of the nonionic surfactant include polyoxyethylene dodecyl ether, polyoxyethylene hexadecyl ether, polyoxyethylene octadecyl ether, polyoxyethylene (9-octadecenyl) ether, and other polyoxyethylene alkyl ethers; Polyoxyethylene phenyl ethers such as polyoxyethylene octyl phenyl ether and polyoxyethylene nonyl phenyl ether; oxirane polymers such as polyethylene oxide, co-polyethylene oxide propylene oxide; sorbitan dodecanoic acid ester, sorbitan hexadecanoic acid ester, Sorbitan octadecanoic acid ester, sorbitan (9-octadecenoic acid) ester, sorbitan (9-octadecenoic acid) triester, polyoxyethylene sorby Ndodekan acid esters, polyoxyethylene sorbitan hexadecanoic ester, polyoxyethylene sorbitan octadecanoic ester, polyoxyethylene sorbitan octadecanoic acid triester,
Polyoxyethylene sorbitan (9-octadecenoic acid)
Esters, sorbitan fatty acid esters such as polyoxyethylene sorbitan (9-octadecenoic acid) triester; sorbitol fatty acid esters such as polyoxyethylene sorbitol (9-octadecenoic acid) tetraester; glycerin octadecanoic acid ester, glycerin (9-octadecene) Acid) esters such as glycerin fatty acid esters are mentioned. Among these nonionic activators, those having an HLB of 14 or more are particularly preferable.

Examples of the water-soluble resin that may be added to the aqueous recording liquid of the present invention include glue, gelatin, casein, albumin, gum arabic, fish glue,
Alginic acid, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, polyethylene oxide, polyvinyl alcohol, polyacrylamide, polyacrylic acid, polyvinyl ether, polyvinylpyrrolidone, styrene-maleic acid copolymer, styrene-acrylic acid copolymer, acrylic ester- Examples thereof include acrylic acid copolymers.

The water-soluble resin is used as necessary for the purpose of improving fixability, viscosity control, and quick-drying property.
When used in the recording liquid, the content ratio of the water-soluble resin in the recording liquid is preferably 0 to 30% by mass, and particularly preferably 0 to 20% by mass.

The aqueous recording liquid of the present invention can be suitably used as an ink for stationery such as felt-tip pens and markers, various printers, plotters, and the like, and particularly, by taking advantage of its excellent dispersibility and dispersion stability. It can be suitably used as an aqueous pigment recording liquid for recording.

[0072]

EXAMPLES Next, the present invention will be explained based on examples. The following parts and% are based on mass unless otherwise specified.

(Synthesis Example 1) (Synthesis of dihalogenoquinacridone sulfonic acid derivative; 3,10-dichloroquinacridone sodium sulfonate A-1) 980 parts of 98% sulfuric acid at 90 ° C. under stirring for 2.5 hours
-350 parts of di (methachloroanilino) terephthalic acid was charged and the sulfonation reaction was carried out for 85 minutes. afterwards,
The reaction temperature was set to 120 ° C. and the cyclization ring closure reaction was carried out for 3 hours. Subsequently, the reaction mixture obtained in the above reaction,
Add to 7000 parts of water at 45 ° C., stir for 30 minutes,
The product was precipitated. The obtained product was filtered to obtain a wet cake, and the wet cake was stirred under a pressure of 8
It was dispersed in 7,000 parts of water at 0 ° C. to make a slurry. Sodium hydroxide was added to the product in the slurry state to adjust the pH to 11, to obtain a slurry of product A-1 having a solid content of 5.5% when dried.

(Synthesis Example 2) (Synthesis of dihalogenoquinacridone sulfonic acid derivative; 3,10-dichloroquinacridone sulfonic acid aluminum A-2) 300 parts of sulfuric acid band was added to the slurry of the product A-1 obtained in Synthesis Example 1. Was added and stirred for 2 hours, and then sodium hydroxide was added to adjust the pH to 6. This was filtered and washed with water to obtain a wet cake of product A-2 having a solid content of 21.8% when dried.

(Synthesis Example 3) (Synthesis of an anionic group-containing organic polymer compound (film-forming resin)) A reaction vessel equipped with a stirring device, a dropping device, a temperature sensor, and a reflux device having a nitrogen introducing device on the upper part thereof Methyl ethyl ketone 500 is placed in a reaction vessel of an automatic polymerization reaction device (polymerization tester DSL-2AS type, manufactured by Todoroki Sangyo Co., Ltd.)
And the inside of the reaction vessel was replaced with nitrogen while stirring.
After the temperature was raised to 75 ° C. while maintaining the nitrogen atmosphere in the reaction container, n-butyl methacrylate 202.6 was added from a dropping device.
Parts, n-butyl acrylate 22.8 parts, methacrylic acid 2
-Hydroxyethyl 75.0 parts, methacrylic acid 100.
0 parts, styrene 99.6 parts and "perbutyl O"
(Active ingredient t-butyl peroxy 2-ethylhexanoate, manufactured by NOF CORPORATION) 40.0 parts of a mixed solution was added dropwise over 2 hours. After completion of the dropping, the reaction was further continued at the same temperature for 15 hours to obtain an anionic group-containing organic polymer compound solution having an acid value of 130, a glass transition temperature (calculated value) of 54 ° C. and a weight average molecular weight of 22,500. After completion of the reaction, a part of methyl ethyl ketone was distilled off under reduced pressure to adjust the nonvolatile content of the resin solution to 50% by weight.

Example 1 (Synthesis of Pigment Composition B-1 Containing Carbon Black and Dihalogenoquinacridone Sulfonic Acid Derivative) 100 parts of 2,5-di (p-toluidino) terephthalic acid was added to a phosphoric acid concentration of 84.0% by weight. % Polyphosphoric acid in the presence of 300 parts by weight of the mixture, the mixture is dehydrated and condensed at 125 ° C. for 3 hours with condensation to cyclize 2,5-di (p-toluidino) terephthalic acid to give 2,9-dimethylquinacridone. A reaction mixture containing was obtained. This reaction mixture was
Suspended water was obtained by pouring into 200 parts of water at 30 ° C. After filtering this, the residue collected by filtration is hot water at 60 ° C and 0.5%.
Was sequentially used to wash to obtain a wet cake of crude dimethylquinacridone pigment having a dry solid content of 27.9%.

The suspension obtained by mixing 340 parts of the obtained wet cake, 370 parts of isobutanol, and 490 parts of water was stirred at 115 ° C. for 5 hours in a closed system for pigmentation.
0.05 part of carbon black (MA-220 manufactured by Mitsubishi Chemical Corporation) and 3,10-dichloroquinacridone aluminum sulfonate (A-2) obtained in Synthesis Example 2 were added to the suspension thus obtained. Add 23 parts of wet cake,
After stirring for 1 hour, the residue was filtered, washed with hot water, dried, and pulverized to obtain a pigment composition B-1.

Example 2 (Synthesis of Pigment Composition B-2 Containing Carbon Black) At the time of pigmentation, 358 parts of the wet cake of dimethylquinacridone crude pigment was used in place of 340 parts of the wet cake to prepare a suspension. Pigment Composition B-as in Example 1 except that the addition of 23 parts of a wet cake of 3,10-dichloroquinacridone aluminum sulfonate A-2 was omitted.
Got 2.

Comparative Example 1 (Quinacridone pigment composition B-
Synthesis of 3) At the time of pigmentation, 358 parts of the wet cake of dimethylquinacridone crude pigment was used in place of 358 parts of the same wet cake, and 0.05 part of MA-220 in suspension, 3,10-
Aluminum dichloroquinacridone sulfonate (A-
A quinacridone pigment composition B-3 containing no carbon black was obtained in the same manner as in Example 1 except that the addition of 23 parts of the wet cake in 2) was omitted.

Example 3 (Synthesis of Pigment Composition B-4 Containing Carbon Black and Dihalogenoquinacridone Sulfonic Acid Derivative) A wet cake of dimethylquinacridone crude pigment having a dry solid content of 32.0% was prepared in the same manner as in Synthesis Example 1. Got 297 parts of the obtained wet cake, 0.05 part of MA-220,
Wet cake 23 of 3,10-dichloroquinacridone aluminum sulfonate (A-2) obtained in Synthesis Example 2
Parts, 370 parts of isobutanol, and 540 parts of water were mixed to obtain a suspension, which was stirred at 115 ° C. for 5 hours in a closed system to form a pigment. The suspension was filtered, the residue collected by filtration was washed with hot water, dried and pulverized to obtain a pigment composition B-4.

Example 4 (Preparation of Aqueous Pigment Dispersion C-1 Containing Carbon Black, Dihalogenoquinacridone Sulfonic Acid Derivative and Other Quinacridone Pigment Derivatives) In a mixing tank equipped with a cooling jacket, as a pigment, Example 1 was used. 95 parts of the pigment composition (B-1) synthesized in 1., 5 parts of phthalimidomethylated-3,10-dichloroquinacridone (average phthalimidomethyl group number 1.4), and the anionic group-containing organic polymer obtained in Synthesis Example 3 Compound solution 40 parts, 25
% Aqueous sodium hydroxide solution 7.4 parts, methyl ethyl ketone 30 parts, and water 222.6 parts were charged and stirred and mixed. The mixed solution is passed through a dispersion device (SC mill SC100 / 32 type, manufactured by Mitsui Mining Co., Ltd.) filled with zirconia beads having a diameter of 0.3 mm, and is circulated (a method in which the dispersion liquid discharged from the dispersion device is returned to the mixing tank). Dispersed for 6 hours. The number of revolutions of the dispersion device was set to 2,700 revolutions / minute, and cold water was passed through the cooling jacket so that the temperature of the dispersion liquid was kept at 40 ° C. or lower.

After the dispersion was completed, the dispersion stock solution was sampled from the mixing tank, and then 800 parts of water was used to wash the mixing tank and the flow path of the dispersion apparatus, and the diluted stock solution was obtained by combining with the dispersion stock solution.

The diluted dispersion liquid was placed in a glass distillation apparatus, and the entire amount of methyl ethyl ketone and a part of water were distilled off. After cooling to room temperature, add 2% hydrochloric acid dropwise with stirring to pH 4.5.
After adjusting to, the solid content is filtered by Nutsche type filtration device,
Washed with water. The cake was placed in a container, 10 parts of a 25% aqueous potassium hydroxide solution was added, and the mixture was dispersed with a dispa (TK Homodispa 20 type, manufactured by Tokushu Kika Co., Ltd.), and further centrifuged (50A-IV type, ( After removing coarse particles at Sakuma Manufacturing Co., Ltd., the nonvolatile content was adjusted to 20%,
Aqueous pigment dispersion C-1 was obtained.

Example 5 (Aqueous Pigment Dispersion C- Containing Carbon Black and Other Quinacridone Pigment Derivatives)
Production of 2) As a pigment, the pigment composition (B-1) synthesized in Example 1
Instead of 95 parts, the pigment composition synthesized in Example 2 (B-
2) Aqueous pigment dispersion C-2 was obtained in the same manner as in Example 4 except that 95 parts was used.

Comparative Example 2 (Preparation of Quinacridone Type Aqueous Pigment Dispersion C-3) As a pigment, the pigment composition (B-1) synthesized in Example 1 was used.
A quinacridone-based aqueous solution containing neither carbon black nor a halogenoquinacridone sulfonic acid derivative in the same manner as in Example 4 except that 95 parts of the quinacridone-based pigment composition (B-3) synthesized in Comparative Example 1 was used instead of 95 parts. Pigment Dispersion C-3 was obtained.

Example 6 (Preparation of Aqueous Pigment Dispersion C-4 Containing Carbon Black and Dihalogenoquinacridone Sulfonic Acid Derivative) As a pigment, the pigment composition (B-1) synthesized in Example 1 was used.
Instead of 95 parts, the pigment composition synthesized in Example 3 (B-
4) Aqueous pigment dispersion C-4 was obtained in the same manner as in Example 4 except that 95 parts were used.

Example 7 (Preparation of Aqueous Pigment Dispersion C-5 Containing Carbon Black and Dihalogenoquinacridone Sulfonic Acid Derivative) As a pigment, the pigment composition (B-1) synthesized in Example 1 was used.
90 parts of the quinacridone pigment composition (B-3) synthesized in Comparative Example 1 instead of 95 parts, 0.05 part of carbon black (# 960 manufactured by Mitsubishi Chemical Corporation), 3,10 synthesized in Synthesis Example 1 -Using 91 parts of a slurry of sodium dichloroquinacridone sulfonate (A-1), the amount of water added was 22
Aqueous pigment dispersion C-5 was obtained in the same manner as in Example 4 except that 136.5 parts was used instead of 2.6 parts.

(Preparation Example 1 of Dispersion) (Preparation of Aqueous Pigment Dispersion C-6 Only of Carbon Black) As a pigment, the pigment composition (B-1) synthesized in Example 1 was used.
95 parts, phthalimidomethylated-3,10-dichloroquinacridone (average phthalimidomethyl group number 1.4) 5 parts instead of carbon black (Mitsubishi Chemical # 960) 1
A carbon black aqueous pigment dispersion C-6 was obtained in the same manner as in Example 4 except that only 100 parts was used.

Example 8 (Preparation of Aqueous Pigment Dispersion C-7 Containing Carbon Black) The quinacridone type aqueous pigment dispersion C-prepared in Comparative Example 2
99.95 parts of No. 3 and 0.05 parts of the carbon black aqueous pigment dispersion C-6 prepared in Dispersion Preparation Example 1 were mixed to obtain an aqueous pigment dispersion C-7.

Example 9 (Preparation of Aqueous Pigment Dispersion C-8 Containing Carbon Black) The quinacridone-based aqueous pigment dispersion C-prepared in Comparative Example 2
99.90 parts of No. 3 and 0.10 part of the carbon black aqueous pigment dispersion C-6 prepared in Dispersion Preparation Example 1 were mixed to obtain an aqueous pigment dispersion C-8.

Comparative Example 3 (Preparation of Aqueous Pigment Dispersion C-9 Containing Excessive Carbon Black) The quinacridone type aqueous pigment dispersion C-prepared in Comparative Example 2
99.80 parts of No. 3 and 0.20 part of the carbon black aqueous pigment dispersion C-6 prepared in Dispersion Preparation Example 6 were mixed to obtain an aqueous pigment dispersion C-9.

Examples 10 to 15 and Comparative Examples 4 to 5 (Preparation Example of Aqueous Pigment Recording Liquid) Using the aqueous pigment dispersions C-1 to C-9 obtained as described above, JP-A-10-95941 describes. With reference to the example (Preparation of ink composition), aqueous pigment recording liquids (D-1 to 9) for inkjet printers were prepared with the following compositions.

[0093] Aqueous pigment dispersion 30 parts Triethylene glycol  Mono-n-butyl ether 10 parts polyethylene glycol                   15 parts Surfynol 465 (manufactured by Air Products) 0.8 parts 44.2 parts of water

Example 16 99.95 parts of a quinacridone-based aqueous pigment recording liquid (D-3) prepared in the same manner as in Example 10 using the quinacridone-based aqueous pigment dispersion C-3 prepared in Comparative Example 2 above. And a carbon black aqueous pigment recording liquid (D) prepared in the same manner as in Example 10 using the aqueous pigment dispersion C-3 containing only carbon black prepared in Dispersion Preparation Example 1 above.
-6) Mixing 0.05 parts of aqueous pigment recording liquid (D-1
0) was obtained.

Printing Evaluation Using the aqueous pigment recording liquids D-1, 2, 4, 5, 7, 8 and 10 containing carbon black prepared in the above examples, an ink jet printer (MJ-8000C type,
Printing was performed on copy paper (made by Xerox Co., Ltd.) with Seiko Epson Corporation. The color density of the printed matter was measured with a Gretag densitometer D-196 (manufactured by Gretag Macbeth), and the hue was visually evaluated. These had high color density, were excellent in tinting strength, and were clear in hue. The results are shown in Table 1.

Further, the quinacridone type aqueous pigment recording liquid D- containing no carbon black prepared in the above Comparative Example.
Printing was performed in the same manner as above using the aqueous pigment recording liquid D-9 containing 3 and carbon black in excess, and the color density and the hue were evaluated. These were inferior in color density and clearness of hue. The results are shown in Table 1.

[0097]

[Table 1] Table 1

The carbon black content in Table 1 is
The content with respect to the quinacridone pigment is shown.

From the above examples, it can be seen that the aqueous pigment recording liquid of the present invention containing carbon black generally has an excellent color density and an excellent coloring power.

As can be seen from the comparison between Example 10 and Example 11, the aqueous pigment recording liquid containing carbon black, the halogenoquinacridone sulfonic acid derivative and the other quinacridone pigment derivative was an aqueous pigment containing carbon black and the other quinacridone pigment derivative. It can be seen that, as compared with the pigment recording liquid, it has a more excellent color density and is excellent in coloring power.

As can be seen from the comparison between Example 10 and Example 13, in the aqueous pigment recording liquid containing carbon black, the halogenoquinacridone sulfonic acid derivative and the other quinacridone pigment derivative, carbon black and halogeno contained in the aqueous pigment dispersion were obtained. The quinacridone sulfonic acid derivative and the other quinacridone pigment derivative are the aqueous recording liquid prepared by using the aqueous pigment dispersion included in the preparation of the pigment composition in the preceding step, and the aqueous pigment containing the same in the dispersion preparation. It can be seen that the aqueous recording liquid prepared by using the dispersion has an excellent color density and an excellent coloring power.

As can be seen from Examples 14 and 15, and Comparative Examples 4 and 5, the content of carbon black is
It can be seen that the intended color density cannot be obtained when the amount is large or small.

[0103]

The quinacridone pigment composition of the present invention is
Then, when the water-based pigment dispersion is prepared, it is possible to provide a water-based pigment dispersion having an excellent color density, which is a remarkable effect. Further, the quinacridone-based aqueous pigment dispersion of the present invention has a particularly remarkable effect that an aqueous pigment recording liquid having an excellent color density can be provided when an aqueous pigment recording liquid is prepared using the same. Furthermore, the quinacridone-based aqueous pigment recording liquid of the present invention exerts a particularly remarkable effect that when it is used for ink jet recording, a printed image having excellent color density can be provided.

Front page continuation (51) Int.Cl. ⁷ identification code FI theme code (reference) C09B 67/46 C09D 11/00 C09D 11/00 B41J 3/04 101Y F term (reference) 2C056 EA13 FC01 2H086 BA53 BA55 BA59 BA62 4J039 BA04 BC50 BE01 GA21 GA24 GA26

Claims (8)

[Claims] 1. A pigment composition comprising a quinacridone pigment and at least 0.01 to 0.1 part by mass of carbon black per 100 parts by mass of the quinacridone pigment. 2. The pigment composition according to claim 1, which further contains a halogenoquinacridone sulfonic acid derivative. 3. An aqueous pigment dispersion containing a quinacridone pigment and at least 0.01 to 0.1 part by mass of carbon black per 100 parts by mass of the quinacridone pigment. 4. The aqueous pigment dispersion according to claim 3, which further contains a halogenoquinacridone sulfonic acid derivative. 5. The aqueous pigment dispersion according to claim 3, further comprising an anionic group-containing organic polymer compound. 6. A quinacridone pigment containing an anionic group-containing organic polymer compound, wherein the quinacridone pigment and the anionic group-containing organic polymer compound are coated with the anionic group-containing organic polymer compound. The aqueous pigment dispersion according to claim 3 or 4. 7. An aqueous pigment recording liquid containing a quinacridone pigment and at least 0.01 to 0.1 part by mass of carbon black per 100 parts by mass of the quinacridone pigment. 8. The aqueous pigment recording liquid according to claim 7, which further contains a halogenoquinacridone sulfonic acid derivative.