JPH08319429A - Colored composition containing ionomer resin - Google Patents

Abstract

PURPOSE: To obtain a colored composition useful for e.g. an ink jet recording ink excellent in dispersibility and free from nozzle plugging by mixing a specified water-self-dispersible resin with a dye or pigment as the essential components. CONSTITUTION: This colored composition contains a water-self-dispersible ionomer resin (A) being a synthetic resin having anionic functional groups (carboxyl groups) [e.g. (meth)acrylic copolymer] in which part of the functional groups form a salt with monovalent counter ions (e.g. ions derived from an alcoholamine) and another part of the functional groups form an intermolecular cross-linkage through polyvalent metals (e.g. barium ions or aluminum ions) and a dye or pigment (B) as the essential components. When this composition is used as an ink jet recording ink composition, it has excellent dispersion stability, is nonproblematic in nozzle plugging because of the contained resin A and is desirably applicable to an elecrophotographic powder toner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coloring composition containing, as essential components, an ionomer resin (1) having substantial thermoplasticity, which is tough and rich in elasticity, and a dye or pigment (2). Such a coloring composition can be suitably applied as an ink for inkjet recording and as a powder toner for electrophotography.

[0002]

2. Description of the Related Art As an ink composition for ink jet recording which has been known for a long time, there is an ink composition in which a soluble dye is dissolved in water and an additive such as a wetting agent is added. However, in the case of such an ink composition, since a water-soluble dye is used, water-soluble dyes have poor water resistance, and oil-based dyes have poor solvent resistance, and also have the drawback that light resistance is poor in common. It was Also, because the dye is dissolved at the molecular level,
When printing on so-called plain paper such as copy paper commonly used in offices, bleeding called whisker-like feathering occurs, which causes a remarkable deterioration in print quality.

Various so-called pigment inks have already been proposed in order to improve the above-mentioned drawbacks. For example, a resin-soluble ink or polymer latex in which carbon black or an organic pigment is dispersed by using a resin as a binder and a dispersant is used. Various resin-dispersed inks containing dyes or pigments have been proposed as microcapsules.

Among the resin-soluble inks, emulsion type non-uniform polymer particles called polymer latex are used. For example, JP-A-54-58504 discloses a mixture of a hydrophobic dye and vinyl polymer fine particles in water. Although an oil-based dispersed aqueous ink composition is described,
Since the dispersion of the dye is unstable and the polymer particles also fuse,
There is a drawback that nozzles are clogged and stable recording is not possible. Further, JP-A-55-139471 discloses an ink composition in which a water-insoluble vinyl polymer latex particle impregnated with a dye is dispersed and heated in an aqueous medium by dispersing and heating the disperse dye in the aqueous vinyl polymer latex. However, it is extremely difficult to completely impregnate the vinyl polymer latex particles with the disperse dye, and the resulting ink composition contains a dispersion of the disperse dye alone, which causes bleeding of the ink image. There is a drawback that it causes.

In order to ameliorate the drawbacks of such a polymer latex, a water-insoluble polymer having a certain organic group bonded thereto is used, which contains an oil-soluble dye and has a nonionic stabilizer permanently bonded thereto. An ink composition in which a water-insoluble polymer is dispersed in a water-alcohol mixed medium is proposed in JP-A-62-172076. However, foaming occurs due to the use of a surfactant in emulsion polymerization of the water-insoluble polymer. In addition, since the nonionic stabilizer is also included in the particles, there is a drawback that the nonionic stabilizer causes the oil dye to bleed and deteriorates the image quality. Furthermore, JP-A-6
No. 2-184072 discloses an ink composition containing a coloring material obtained by coloring polymer latex particles having a reactive group with a dye having a functional group capable of reacting with the reactive group to form a covalent bond. Although proposed, it is necessary to heat the polymer particles for a long time in order to color the polymer particles with a dye having a functional group, so that there is a drawback that the polymer particles aggregate and precipitate. Further, there is a drawback that an extremely complicated operation is required to remove the dye having an unreacted functional group.

On the other hand, as an example of a resin dispersion type ink, in JP-A-62-95366, a water-insoluble polymer such as polystyrene and polymethylmethacrylate and an oily dye are dissolved in a water-insoluble organic solvent, and surface active An ink composition for a jet copying method has been proposed which comprises an ink containing a dye encapsulated in polymer particles by evaporating the solvent after mixing with an aqueous solution containing an agent to emulsify it. Further, in JP-A-62-254833, the interfacial tension between the organic solvent and water during encapsulation is set to 10 dynes or less.
In addition to the aqueous writing liquid, fiber coloring, a method for producing a colorant aqueous suspension that can be applied in various fields such as cosmetics has been proposed, and alkylated vinylpyrrolidone, polyvinyl butyral, polyvinyl acetal, as a water-insoluble polymer used here, Examples include water-insoluble polymers such as styrene / maleic anhydride copolymers. However, in ink-jet printer inks of the capsule type that use these water-insoluble polymers, particles easily aggregate and adhere with evaporation of water and organic solvent, and heat-resistant storage and avoid nozzle clogging during evaporation of water. I couldn't do it.

Further, in JP-A-3-186343, a solution of a poorly water-soluble core substance containing a hydrolyzable metal chelate compound is dispersed in an aqueous medium containing a wall substance capable of reacting with a hydrolyzate of the metal chelate compound. Has proposed a method for obtaining microcapsules, the mechanical strength of the resulting capsules is lowered by the presence of the core substance due to the polymerization on the surface of the poorly water-soluble core substance. It is difficult to control the particle size and the tendency that the particle size becomes non-uniform cannot be avoided. JP-A-5-237370 also proposes a continuous production method of microcapsules having a chelate resin obtained by mixing polyvinyl alcohol or a derivative thereof and zirconium chloride as a wall film. However, water-soluble polyvinyl alcohol and zirconium It is limited to the combination of organic chlorides, and there is a drawback that the corrosion of the print head due to the generation of chlorine ions due to the use of zirconium chloride as a raw material cannot be avoided.

On the other hand, in the field of powder toner for electrophotography,
Various proposals have been made to which the above-mentioned microencapsulation technology is applied. Specifically, JP-A-5-66600 proposes a capsule-type toner in which an anionic self-water-dispersible resin contains a dye / pigment. However, with a thermoplastic resin made of a linear polymer in which such anionic functional groups are just neutralized, the fixing temperature range in heat roll fixing is narrow, and it is difficult to simultaneously satisfy heat-resistant storage stability. It was

Further, in JP-A-55-166651 and JP-A-56-94362, fixing failure or offset phenomenon using a binder resin in which a specific carboxyl group-containing polymer is crosslinked with a polyvalent metal ion is used. Although electrostatic charge developing toners excellent in heat roll fixing suitability have been proposed, all of them have a crosslinked structure with polyvalent metal ions,
According to a method in which a binder resin having no hydrophilic group is used, and the binder resin, a dye, a pigment and the like are collectively melt-kneaded and pulverized.
For this reason, the obtained resin kneaded product has a drawback that the pulverizability is remarkably poor because it is tough and has elasticity, and the particle size range of the obtained toner is wide.

[0010]

SUMMARY OF THE INVENTION The present invention solves the problems based on the polymers used in the ink jet recording ink, microcapsules, electrophotographic powder toner and the like.

That is, an object of the present invention is that at least a part of the functional groups in the synthetic resin having an anionic functional group forms a salt with a monovalent counterion, and the salt is localized on the surface. Another object of the present invention is to provide a coloring composition which maximizes the characteristics of the self-water-dispersible ionomer resin (1) based on a new molecular structure. Further, the object of the present invention is to take advantage of the characteristics of the coloring composition, for example, excellent in dispersion stability,
Another object of the present invention is to provide an ink composition for inkjet recording, which does not have a problem of nozzle clogging due to agglomeration of particles in the ink or agglomeration of particles due to water evaporation. Still another object of the present invention is to provide a powder toner composition for electrophotography, which is more excellent in chargeability, by making the best use of the characteristics of the coloring composition.

[0012]

The above object can be achieved by the present invention described below. That is, in the present invention, at least a part of the functional group (a) in the synthetic resin (A) having an anionic functional group (a) forms a salt with a monovalent counterion (b), and further the functional group A self-water-dispersible ionomer resin (1) in which at least another part of the group (a) forms an intermolecular crosslinked structure through a polyvalent metal ion (c), and a dye / pigment (2)
The present invention relates to a coloring composition containing as an essential component. Further, the present invention relates to an ink composition for ink jet recording containing at least such a coloring composition and a powder toner composition for electrophotography comprising the coloring composition.

In the colored composition of the present invention, as the resin contained in the composition, at least a part of the anionic functional groups in the synthetic resin is neutralized with a monovalent base, and Another feature is the use of a self-water-dispersible ionomer resin having a structure in which at least a part of the other is intermolecularly crosslinked by an ionic bond due to a polyvalent metal ion.

Such a resin is based on the fact that at least a part of the functional groups in a synthetic resin having an anionic functional group forms a salt with a monovalent counterion, and the salt is localized on the surface. It also exhibits self-water dispersibility and is a chelating resin by ionic bonding of polyvalent metal ions and anionic groups that form a reversible gel with a reversible cross-linking network structure different from covalent cross-linking. . This self-water-dispersible ionomer resin has extremely tough and elastic performance, little aggregation between resin particles, and a characteristic of ionic bond is that its binding energy is small compared with covalent bond. Good thermoplasticity is exhibited even if the crosslinking rate is high. Therefore, when the coloring composition of the present invention containing such a self-water-dispersible ionomer resin is prepared and used, a synergistic effect of being self-water-dispersible and being an ionomer resin results in an ink jet recording ink. The use composition is excellent in dispersion stability and has no problem of nozzle clogging due to agglomeration of particles in ink or agglomeration of particles due to evaporation of water or the like, and is suitable for this application. Even when this colored composition is prepared and used for a powder toner for electrophotography, the charging property is better, the heat-resistant storage stability is excellent, the fixing temperature range in hot pressure roll fixing is wide, and there is no so-called offset, After all, it is also suitable for this application.

The self-water-dispersible ionomer resin (1) used in the present invention is a synthetic resin (A) having an anionic functional group (a). It is an ionomer resin obtained by reacting with a valent metal salt.

The anionic functional group (a) in the resin (A) is a carboxyl group, a sulfonic acid group, a sulfinic acid group or the like and is not particularly limited. Of these, the carboxyl group is general, It gives a good self-water dispersible ionomer resin.

The acid value of the synthetic resin (A) having the functional group is not particularly limited, but if it is less than 10, the emulsifying property and the crosslinking performance at the time of salt formation are insufficient.
If it exceeds 0, the resin tends to swell or dissolve in water due to neutralization of the base, and the water resistance tends to be remarkably poor. Therefore, the acid value of the synthetic resin (A) is preferably in the range of 10 to 200.

Synthetic resin (A) having an anionic functional group
Examples of the resin include resins soluble in an organic solvent such as acrylic acid resin, polyester resin, and epoxy resin. For example, at least one monomer selected from the group consisting of styrene, substituted styrene, and (meth) acrylic acid ester,
A copolymer with (meth) acrylic acid has good water resistance and is preferable. Specifically, styrene or substituted styrene such as α-methylstyrene, acrylic acid methyl ester,
Acrylic acid ester such as acrylic acid ethyl ester, acrylic acid butyl ester, acrylic acid 2-ethylhexyl ester; selected from methacrylic acid methyl ester, methacrylic acid ethyl ester, methacrylic acid butyl ester, methacrylic acid 2-ethylhexyl ester and the like. A (meth) acrylic acid-based copolymer containing at least one monomer and at least one monomer selected from acrylic acid and methacrylic acid is preferable. The molecular weight range of the resin is also not particularly limited, but those having a molecular weight of 1,000 or more and 100,000 or less are more preferable. Further, if a microcapsule type is produced, the resin is not particularly limited as long as it forms a stable microcapsule when combined with an aqueous medium, and two or more types are mixed at the same time. You may use it.

As described above, in the self-water-dispersible ionomer resin (1) used in the present invention, at least a part of the anionic functional group (a) in the synthetic resin (A) is a monovalent counter ion (b). And forms a salt. Examples of the monovalent counter ion (b) here include an alkali metal ion and an ammonium ion generated from a water-soluble monovalent base (B) described later.

In the self-water-dispersible ionomer resin (1), the other part of the anionic functional group (a) in the synthetic resin (A) is intermolecularly crosslinked via the polyvalent metal ion (c). Has been done. The polyvalent metal ion (c) is produced by the reaction between the anionic functional group (a) in the synthetic resin (A) and the polyvalent metal salt (C) soluble in an organic solvent described later. The valence of the polyvalent metal ion (c) may be 2 or more, but is preferably 2 or 3. Particularly preferred as the polyvalent metal ion (c) is calcium ion,
It is at least one selected from barium ions, magnesium ions, zinc ions, and aluminum ions. Self-water-dispersible ionomer resins with a structure of intermolecular crosslinking through these metal ions are generally colorless,
It has low toxicity, good toughness, and good thermoplasticity. The coloring composition of the present invention containing the self-water-dispersible ionomer resin cross-linked with these metal ions has an advantage that the coloration by the metal ions is small and the colors of the dyes and pigments used in combination can be faithfully reproduced.

When the synthetic resin (A) is crosslinked via the polyvalent metal ion (c), the optimum ionomer resin can be obtained depending on the acid value and molecular weight of the synthetic resin and the valence of the polyvalent metal ion. Therefore, the cross-linking rate may be selected.

When the resin (A) is used as a toner, Tg
(Glass transition point) is preferably 40 to 80 ° C, and when used in ink, Tg is preferably adjusted to 40 to 120 ° C.

On the other hand, the dye / pigment (2) used in the coloring composition of the present invention includes, for example, magnetic powder, carbon black,
Inorganic pigments such as titanium black, titanium white, zinc sulfide and red iron oxide, phthalocyanine pigments, monoazo pigments, azo pigments such as disazo pigments, phthalocyanine pigments, organic pigments such as quinacridone pigments, azo pigments, metal complex salt pigments, anthraquinone pigments, Dyes such as triallylmethane dyes and disperse dyes are used, but the dyes are not limited to these. The amount of the dye / pigment used is the same as that of the resin (1) 1
1 to 500 parts by weight are used per 00 parts by weight. The amount of the dye or pigment added is not particularly limited as long as the effects of the present invention are achieved, but, for example, in the finally obtained ink or electrophotographic powder toner, it may be 0.
The amount is preferably 5 to 10% by weight.

In order to obtain the above ink or toner from the resin (1) and the dye / pigment (2), any known and commonly used method can be adopted.

An essential constituent of the coloring composition of the present invention,
Self-water dispersible ionomer resin (1) and dye / pigment (2)
In order to prepare an aqueous ink composition for inkjet recording containing at least, an ionomer resin (1) and a dye / pigment (2) in an aqueous medium according to a known method.
A composition containing at least and may be prepared. The form of the prepared water-based ink composition may be a so-called resin-soluble ink or a resin-dispersed ink. As a preferred production method, a method of adding a dye or pigment to the raw material components or the reaction system and dissolving or dispersing it at an arbitrary stage during the production of a known aqueous dispersion of an ionomer resin is preferable. Specifically, in the presence of an organic solvent, a synthetic resin (A) having an anionic functional group (a) capable of self-water dispersion by neutralization and the functional group (a) are neutralized. Water-soluble monovalent base (B) and a polyvalent metal salt (C) soluble in an organic solvent are reacted to obtain a self-water-dispersible ionomer resin in an organic solvent solution, and an aqueous medium containing water as an essential component Method of adding the above; a method of adding the aqueous medium to the organic solvent solution of the self-water-dispersible ionomer resin; the above-mentioned synthetic resin (A) having an anionic functional group in the absence of an organic solvent. A method of melt-kneading the monovalent base (B) and the above-mentioned polyvalent metal salt (C), and adding the kneaded product to an aqueous medium containing water as an essential component; a method of adding the aqueous medium to the kneaded product. Having an anionic functional group (a) in the presence of an organic solvent An organic solvent solution of the synthetic resin (A) and the polyvalent metal salt (C) and not a water-dispersible obtained by reacting an ionomer resin that,
A method of adding an aqueous medium containing a monovalent base (B); a method of adding an organic solvent solution of an ionomer resin which is not water-dispersible to the aqueous medium described above; In the method, there may be mentioned a method in which a dye or pigment is added to a raw material or a reaction system at an arbitrary stage, and this is dissolved or dispersed. The dye or pigment may be added as it is or in the form of a solution or dispersion.

As a suitable production method for obtaining a microcapsule type aqueous ink composition for ink jet recording using the coloring composition of the present invention, a synthetic resin (A) and a polyvalent metal salt generally called a mill base are used. A dye or pigment is dissolved or dispersed in an organic solvent solution containing (C), and a water-soluble monovalent base (B) is further mixed and dissolved in this colored mill base to further neutralize the ionically crosslinked synthetic resin. It is preferable to use a so-called phase inversion emulsification method in which a self-dispersing resin is prepared and then the mixture is mixed with an aqueous medium containing water as an essential component by dropping and the like to emulsify. In this case, in an aqueous medium containing water as an essential component, a solution containing a self-water-dispersible ionomer resin may be added, but conversely, adding an aqueous medium to a solution containing the resin provides a uniform particle size. It is preferable in that an aqueous dispersion can be obtained. If necessary, a surfactant may be used in combination, and the emulsion may be forcibly emulsified. However, it is preferable not to use a surfactant or protective colloid because it tends to deteriorate the physical properties of the finally obtained particles. According to the phase inversion emulsification method, substantially spherical particles in which the dye / pigment (2) is dissolved in the resin (1) or the dye / pigment (2) is included in and integrated with the resin (1) are obtained, which is preferable. The inclusion includes dispersion.

The organic solvent for dissolving the synthetic resin (A) having an anionic functional group used in the production includes
For example, acetone, dimethyl ketone, a ketone solvent such as methyl ethyl ketone, an alcohol solvent such as methanol, ethanol, isopropyl alcohol, chloroform,
Dissolve resins such as chlorine-based solvents such as methylene chloride, aromatic solvents such as benzene and toluene, ester-based solvents such as ethyl acetate, glycol ether-based solvents such as ethylene glycol monomethyl ether and ethylene glycol dimethyl ether, and amides. Anything can be used. When the resin component is an acrylic resin, at least 1 selected from a ketone solvent and an alcohol solvent.
It is good to combine more than one type. The amount of the organic solvent used is not particularly limited as long as the effect of the present invention is achieved, but the weight ratio of synthetic resin / the organic solvent is 1/1 to 1/2.
The amount is preferably 0.

If necessary, a dispersant, a plasticizer, an antioxidant, an ultraviolet absorber or the like may be used in the synthetic resin solution as an additive together with a solvent, a resin and a dye / pigment. Examples of the water-soluble monovalent base (B) include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide and lithium hydroxide, basic substances such as ammonia, triethylamine and morpholine, triethanolamine and diethanolamine. Alcohol amine-based basic substances such as N-methyldiethanolamine can be used, but are not limited thereto. When a monovalent water-soluble base (B) is mixed with an organic solvent solution of synthetic resin (A) to neutralize the resin and then emulsify, an organic basic substance having good compatibility with the organic solvent is used. It is more preferable to use.

The water-soluble monovalent base (B) is preferably used in an amount corresponding to 60% or more, preferably 80 mol% or more of the anionic functional group of the synthetic resin. If necessary, the base (B) may be added in an amount corresponding to 100 mol% or more depending on the intended use of the coloring composition. When the amount of the monovalent base (B) added is increased, a colored composition having a fine particle size and stable can be obtained, which is suitable for use in an ink composition for inkjet recording. In particular, when the water-soluble monovalent base (B) used for neutralization was alcohol amine, the dispersion stability was more excellent, and nozzle clogging due to particle aggregation due to evaporation of water or organic solvent was improved. An aqueous or oil-based ink for inkjet recording can be obtained. When the amount of the monovalent base (B) added is reduced, the particle diameter of the colored composition particles can be increased, and by adjusting it, a powder toner for electrophotography having an arbitrary particle diameter can be obtained.

On the other hand, the polyvalent metal salt (C) soluble in an organic solvent is not limited as long as it is an alcoholate, an acylate or a chelate of a divalent or higher valent metal and is soluble in the organic solvent described later. There is no particular limitation. Resin particles with a structure intermolecularly cross-linked via metal ions are colorless, have little toxicity, show good toughness and show good thermoplasticity, and are therefore polyvalent metals such as calcium, barium, magnesium, zinc and aluminum. An alcoholate; an acylate obtained from the alcoholate and an organic carboxylic acid such as acetic acid, propionic acid, butyric acid, and the alcoholate, an acylate and, for example, acetylacetone, a β-diketone typified by propionylacetone, or an acetoacetic acid alkyl ester, It is preferable to use chelates obtained from a chelating agent such as β-keto acid esters represented by diacetoacetic acid alkyl ester. Preferred are polyvalent metal acylates and chelates. Further, these polyvalent metal salts may be used in combination.

The cross-linking of the synthetic resin (A) with the polyvalent metal salt (C) of the present invention is most suitable for the intended use depending on the acid value, molecular weight and valence of the polyvalent metal ion (c) of the synthetic resin (A). The crosslinking rate may be selected so that resin particles can be obtained. Usually, the amount of the polyvalent metal salt (C) used is sufficient to correspond to about 1 to 30 mol% of all the anionic functional groups. When a polyvalent metal salt such as an acylate is used in an attempt to obtain a resin having a high crosslinking rate by increasing the amount used, the solubility of the crosslinked resin in an organic solvent is lowered and gelation easily occurs. However, depending on the means of addition, the polyvalent metal salt (C) in an amount corresponding to 100 mol% can be added. For example, even if the addition amount of the polyvalent metal salt (C) reaches 100 mol% of all the anionic functional groups, the chelating agent is added to the polyvalent metal ion in an excessive amount (surplus) with respect to the synthetic resin. (A), a monovalent base (B), and a polyvalent metal salt (C) are added to a solution of an organic solvent and the reaction is carried out in the presence of the organic solvent, or the above-mentioned (A), (B), ( When a means such as adding an excessive amount of a chelating agent to the organic solvent solution containing the self-water-dispersible ionomer resin (1) before emulsification obtained by reacting the component C) is used, the resin is crosslinked. The mask effect described above occurs, and the resin can be emulsified into fine particles without gelation. When the surplus amount of the chelating agent is present in the resin emulsion, the substantial crosslinking of the resin is reduced in equilibrium, but the resin emulsion is stably dispersed in the aqueous medium. Then, when this chelating agent is also distilled off during the distillation of the other organic solvent in the resin emulsion, the equilibrium is largely inclined to the crosslinking of the resin, and as a result, the aqueous dispersion containing the ionomer resin having a high crosslinking rate is obtained. can get. The type of chelating agent that can be added in excess is not particularly limited, but it is preferable to use a volatile and easily distillable one such as acetylacetone, acetoacetic acid ester, and diacetoacetic acid alkyl ester. The addition amount (surplus amount) is also not particularly limited, but if the polyvalent metal salt (C) in an amount corresponding to the low crosslinking rate is added, the addition amount of the chelating agent is small and it corresponds to the high crosslinking rate. If the amount of the polyvalent metal salt (C) is added, the amount of the chelating agent added may be increased. The particle diameter of the resulting crosslinked resin emulsion tends to be finer when the amount of the chelating agent added is large.

In order to make the cross-linking by the polyvalent metal ion in the synthetic resin (A) of the present invention uniform, a soluble polyvalent metal salt is mixed and dissolved in an organic solvent solution of the synthetic resin before emulsification. Alternatively, it is preferable to mix an organic solvent solution of a synthetic resin with an organic solvent solution of a soluble polyvalent metal salt.
Then, a water-soluble monovalent base (B) is mixed and dissolved in a colored mill base in which dyes and pigments are dissolved or dispersed in this mill base, and the ionically crosslinked synthetic resin is further neutralized to form a self-dispersing resin, and then dropped. It is preferable that the mixture is mixed with an aqueous medium containing water as an essential component for emulsification.

When the synthetic resin (A) used in the present invention has a high crosslinking rate by the polyvalent metal ion (c), the resin may gel at room temperature in an organic solvent or during emulsification. By heating the solvent solution or the solution during emulsification, gelation of the synthetic resin in the organic solvent can be prevented, and a colored composition having a high crosslinking rate can be obtained.

Further, by mixing with the above self-water-dispersible resin solution,
Water contained as an essential component in the aqueous medium used for emulsification, in order to maintain the stability of the particles, for example, to avoid nozzle clogging in the ink for inkjet recording, electrophotographic powder toner further described below. In order to secure stable charging performance, water of ion-exchanged water or higher grade is preferable.

When the aqueous dispersion containing the coloring composition obtained according to the above-mentioned production method is used as it is as an aqueous dispersion, a step of removing an organic solvent having a boiling point lower than that of water after emulsification is introduced. It is desirable to prepare it in advance, whereby the dissolution and swelling of resin particles and the like is minimized, and a more stable aqueous dispersion is obtained.

The particle size in the ink is usually 0.001-1.
It is common to prepare it in the micron range.

When an aqueous dispersion containing the coloring composition of the present invention is put to practical use as an aqueous ink composition for ink jet recording, it is preferable to use a water-soluble organic solvent for preventing drying as a drying inhibitor. The anti-drying agent has an effect of preventing the ink from drying at the jet nozzle of the ink jet, and usually has a boiling point equal to or higher than that of water. Examples of such anti-drying agents include conventionally known polyhydric alcohols such as ethylene glycol, diethylene glycol, polyethylene glycol and glycerin, pyrrolidones such as N-methyl-2-pyrrolidone and 2-pyrrolidone, amides and dimethyl. Examples thereof include sulfoxide and imidazolidinone, but are not limited thereto. Although the amount of the anti-drying agent used varies depending on the type, it is usually appropriately selected from the range of 1 to 150 parts by weight with respect to 100 parts by weight of water, but glycerin and another anti-drying agent are used in combination. In this case, 10 to 50 parts by weight is suitable.

If necessary, a water-soluble organic solvent having a permeability-imparting effect may be added as a permeability-imparting agent in order to make the ink jet-jetted and adhere to the paper better. As the penetrating agent, lower alcohols such as ethanol and isopropyl alcohol, glycol ethers such as diethylene glycol-N-butyl ether, and the like can be used, but the penetrating agent is not limited thereto. The amount of the penetrating agent used is not particularly limited as long as the effect of the present invention is achieved, but is preferably an amount such that it becomes 0.1 to 10% by weight in the finally obtained aqueous ink. If necessary, a water-soluble resin, pH adjuster,
Surfactants, preservatives for dispersion, defoaming, and penetration into paper
Additives such as chelating agents can be added. These additives may be added to the aqueous solution for emulsification or after their emulsification, but it is preferable to avoid adding the additives after the final filtration.

When an oil-based ink composition for ink jet recording containing the coloring composition of the present invention is prepared, it is preferable to increase the crosslinking rate as much as possible in order to prevent the swelling and dissolution of the resin particles. The oil-based ink composition may be prepared by drying an aqueous dispersion containing the coloring composition of the present invention and directly extracting it as a powder, and then dispersing it in an organic solvent to prepare an oil-based ink composition. It is preferable to adopt the method of directly substituting the water with the organic solvent because the dye and pigment, the resin particles and the like in the colored oil-based ink composition are less aggregated.

Organic solvents used in preparing the oil-based ink composition include alcohols such as ethanol and propyl alcohol, ketones such as acetone and methyl ethyl ketone, and pyrrolidones such as 2-pyrrolidone and N-methyl-2-pyrrolidone. , Glycols such as ethylene glycol / diethylene glycol propylene glycol, glycol ethers such as diethylene glycol monomethyl ether / diethylene glycol dimethyl ether / propylene glycol monomethyl ether / dipropylene glycol monomethyl ether, high boiling aromatic solvents such as alkylnaphthalene / phenethylcumene, etc., Any organic solvent that can be used in conventional oil-based inks and does not dissolve the coloring composition of the present invention can be used, and two or more kinds may be used in combination.

An organic solvent which is compatible with water and has a vapor pressure lower than that of water is directly mixed with an aqueous dispersion containing the coloring composition of the present invention, and then water is distilled off to give the coloring composition. A solvent dispersion is obtained. In the case of an organic solvent which is incompatible with water and has a vapor pressure lower than that of water, it is directly mixed with an aqueous dispersion containing a coloring composition using an emulsifier, and then colored by distilling off the water. A solvent dispersion of the composition is obtained. In the case of organic solvents that have a higher vapor pressure than water,
After distilling off the water of the coloring composition dispersion, the coloring composition is redispersed in an organic solvent to obtain an organic solvent dispersion of the coloring composition. There is a difference in the polarity of the organic solvent and the surface polarity of the coloring composition, when the aggregation tendency of the coloring composition particles occurs, a dispersant may be used as an auxiliary agent, or the anionic functional group on the surface of the coloring composition may be used. The reactivity may be utilized to bring the surface polarity of the particles closer to the polarity of the organic solvent by treatment with a higher aliphatic amine or the like to prevent aggregation.

If necessary, conventionally known additives such as a resin, a dispersant, a conductivity-imparting agent, an antioxidant, and an ultraviolet absorber are added to the organic solvent dispersion of the coloring composition to obtain an oil-based ink. Also good.

Further, the powder toner composition for electrophotography using the coloring composition of the present invention containing the self-water-dispersible ionomer resin (1) and the dye / pigment (2) as essential components is more favorable. It exhibits chargeability and excellent heat roll fixing characteristics, and can be suitably used as a powder toner for electrophotography. In particular, the one using an aliphatic amine as the water-soluble monovalent base (C) is suitable for the powder toner composition for electrophotography.

As a method of preparing a powder toner for electrophotography using the coloring composition of the present invention, a known method may be appropriately used. The prepared toner may be either the one in which the dye and pigment and the resin are simply uniformly dispersed, or the capsule-type toner in which the dye and the pigment are encapsulated in the resin. The production method is not particularly limited, but as an example thereof, described in the method for producing an ink composition for inkjet recording described above, by a phase inversion emulsification method, an aqueous dispersion in which a coloring composition is dispersed in an aqueous medium is prepared. A method for producing a capsule-type toner in which the colored composition is obtained and then separated and dried is exemplified. According to this method, it is possible to obtain toner particles having a good fluidity and having a spherical shape, which cannot be obtained by the conventional dry-type manufacturing method of melt-kneading and pulverizing and classifying.

As a method for separating and drying the aqueous dispersion to obtain a toner, there are evaporation by vacuum distillation, solid-liquid separation by means such as filtration and centrifugation, and drying by various drying devices. Generally, the particle size of the toner is usually adjusted to be in the range of 0.5 to 15 μm.

When the monovalent base for neutralization is ammonia or an aliphatic amine, the drying can be easily performed. Further, when the monovalent base for neutralization is ammonia, the ammonia is easily volatilized with drying, and becomes a free carboxyl group. Further, in the case of an aliphatic amine, the amine is easily removed by a so-called reverse neutralization means in which an aqueous dispersion containing a coloring composition is added with a strong acid such as hydrochloric acid and treated,
It becomes a free carboxyl group. When a monovalent base for neutralization is converted into a free carboxyl group, an electrophotographic powder toner having a negative triboelectrification polarity is obtained. Further treatment with a higher aliphatic amine gives an electrophotographic powder toner having a positive triboelectrification polarity.

When the coloring composition of the present invention is used as a powder toner for electrophotography, a charge control agent such as a chromium complex salt or an offset such as polyethylene wax or polypropylene wax may be added to the particles of the coloring composition or on the surface of the particles, if necessary. Other additives such as an inhibitor and a fluidity imparting agent such as silica, which are known in conventional powder toners, may be used. These additives are added to an organic solvent mixed liquid containing a synthetic resin (A), a polyvalent metal salt (C), a dye / pigment (2), etc.,
Although it may be dispersed or post-added to the obtained coloring composition, it is preferable that the charge control agent and the wax are added in the former case and the fluidity-imparting agent is added in the latter case. Further, the powder toner particles obtained in the present invention have a narrow distribution and can be used as a toner as they are, but may be classified if necessary.

The toner thus obtained can be used as it is as a magnetic one-component developer, a non-magnetic one-component developer or in combination with a carrier as a two-component developer. In preparing a two-component developer, generally 5 to 300 parts of carrier is used per 100 parts of toner.

Since the coloring composition of the present invention is basically water-insoluble crosslinked particles, the coloring composition is further obtained by a means such as sulfonation or addition of ethylene oxide after the coloring composition is obtained, if necessary. It can also increase the hydrophilicity of the material.

The coloring composition of the present invention can be applied not only as the ink composition for ink jet recording and the powder toner for electrophotography described above, but also as a coloring composition for other inks and paints.

[0051]

EXAMPLES Next, the present invention will be described more specifically with reference to Examples and Comparative Examples. Incidentally, "part" in the following examples
Represents "parts by weight".

Example 1 Styrene acrylic acid resin (styrene / acrylic acid / acrylic acid 2-ethylhexyl ester = 77/13/10; acid value 100; molecular weight 40,000) 1
0 part, carbon black 10 parts, aluminum acetate 4 parts (amount corresponding to 1% cross-linking rate), acetylacetonato aluminum 6 parts (amount corresponding to 9% cross-linking rate), 50 parts methyl ethyl ketone, glass with a diameter of 0.2 mm Beads 150
Dispersion was performed for 4 hours using a paint shaker together with the parts.

To 170 parts of the dispersion excluding glass beads, 40 parts of methyl ethyl ketone and 40 parts of isopropyl alcohol were added.
And 4.8 parts of triethanolamine (amount corresponding to 90% neutralization rate), 130 parts of glycerin with stirring,
A mixed solution of 420 parts of ion-exchanged water was added dropwise at a rate of 5 ml per minute to obtain a colored composition dispersion liquid. The organic solvent was distilled off from the resulting colored composition dispersion using a rotary evaporator to obtain an aqueous dispersion of the colored composition having a particle size of 0.2 μm, which was then filtered using a 1.5 μm membrane filter. This was used as an ink for inkjet printers.

The obtained ink had good dispersibility even when left in a glass container in an environment of 60 ° C. for 1 year, and did not generate aggregates. As a result of a jet test using a piezo type ink jet printer, nozzle clogging was found. In addition, stable jetting was possible, the characters of the obtained plain paper print did not bleed, and the water resistance was excellent.

(Comparative Example 1) A composition obtained by excluding aluminum acetate and acetylacetonato aluminum from Example 1 was used.
An ink for inkjet printer was obtained in the same manner as in Example 1.

The obtained ink was subjected to a jet test using a piezo type ink jet printer, and as a result, nozzle clogging and stable jetting were possible, the characters of the obtained plain paper print did not bleed, and the water resistance was high. However, as a result of being left in a glass container in an environment of 60 ° C. for 1 year, some black aggregates were precipitated.

(Example 2) Styrene acrylic acid resin (styrene / acrylic acid 2-ethylhexyl ester / methacrylic acid = 65/20/15; acid value 100; molecular weight 2)
36 parts, carbon black 4 parts, magnesium acetate 3.8 parts (corresponding to a crosslinking rate of 20%), low molecular weight polypropylene wax 0.5 parts, methyl ethyl ketone 50 parts together with glass beads having a diameter of 3 mm and a paint shaker. Dispersed for 2 hours. To 94 parts of this dispersion, 40 parts of methyl ethyl ketone, 40 parts of isopropyl alcohol, and 3.8 parts of triethylamine (amount corresponding to a resin neutralization rate of 60%) were added to prepare a mill base. This mill base 100
While stirring the parts, 500 parts of water was added dropwise at a rate of 5 ml per minute to obtain a colored composition. Methyl ethyl ketone and ethanol were distilled off from the obtained colored composition using a rotary evaporator, and 1% hydrochloric acid was added to the colored aqueous dispersion to adjust the pH to 2
And then washed with water, and then dried under reduced pressure to obtain a true spherical powder toner having a particle diameter of 5 μm. This toner used an ionomer resin having no self-water dispersibility and had better chargeability and fluidity than the toner obtained by the conventional dry method.

Comparative Example 2 A powder toner having a particle size of 5 μm was obtained in the same manner as in Example 2 except that magnesium acetate was removed from the mill base composition of Example 2.

(Storage Test) The obtained powder toner was put in a cup and allowed to stand for 1 week in an environment of 50 ° C., and the aggregation state was visually examined.

[0060]

[Table 1] Example 2 toner Comparative example 2 toner ────────────────────────── Aggregation state None Cake

(Fixing Test) 4 parts of the obtained powder toner having a particle size of 5 μm was mixed with 96 parts of 200-mesh carrier iron powder to form a developer, and a commercially available copying machine was modified to prepare an experimental machine without a fixing unit. Then, copying was carried out to obtain a test image paper on which toner was not fixed.

On the other hand, a fixing device in which a metal roll whose surface is covered with Teflon and which has a heater incorporated therein so that the surface temperature can be adjusted in the range of 140 to 200 ° C., and a silicon rubber roll which is in pressure contact with this roll are arranged vertically are provided. It was used to fix the unfixed image. As a result, the following fixing results were shown.

[0063]

Table 2 Example 2 toner Comparative example 2 toner ────────────────────────────────── Minimum fixing temperature 160 ℃ 150 ℃ Offset start temperature 200 ℃ 150 ℃

From the above results, the powder toner made of the coloring composition of the present invention exhibits excellent heat-resistant storage and hot-roll fixing properties.

[0065]

The coloring composition of the present invention contains a self-water-dispersible ionomer resin which exhibits a synergistic effect of being self-water-dispersible and being an ionomer resin. When used in an ink composition for inkjet recording, it exhibits excellent effects such as more excellent dispersion stability and no problem of nozzle clogging due to aggregation of particles in the ink or aggregation of particles due to evaporation of water. Further, when a powder toner composition for electrophotography is prepared using the coloring composition, the charging property is better, the fixing temperature range in hot-press roll fixing is wider, and the heat-resistant storage stability is satisfied at the same time. Gives the excellent effect of.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G03G 9/087 G03G 9/08 321

Claims (12)

[Claims] 1. A synthetic resin (A) having an anionic functional group (a), at least a part of said functional group (a) forms a salt with a monovalent counterion (b), and further said functional group. (A)
A coloring composition containing, as essential components, a self-water-dispersible ionomer resin (1) in which at least a part of the other forms an intermolecular crosslinked structure through a polyvalent metal ion (c), and a dye or a pigment (2). Stuff. 2. The coloring composition according to claim 1, wherein 1 to 500 parts by weight of the dye or pigment (2) is used per 100 parts by weight of the resin (1). 3. The coloring composition according to claim 1, wherein the polyvalent metal ion (c) has a valence of 2 or 3. 4. The coloring composition according to claim 5, wherein the polyvalent metal ion (c) is at least one metal ion selected from barium ion, calcium ion, magnesium ion, zinc ion and aluminum ion. . 5. The coloring composition according to claim 1, wherein the anionic functional group (a) of the synthetic resin (A) is a carboxyl group. 6. The acid value of the synthetic resin (A) is from 10 to 200.
The coloring composition according to claim 1, which is 7. The coloring composition according to claim 5, wherein the synthetic resin (A) is a resin soluble in an organic solvent. 8. The synthetic resin (A) is a copolymer of (meth) acrylic acid and at least one monomer selected from the group consisting of styrene, substituted styrene and (meth) acrylic acid ester. The coloring composition described. 9. An ink composition for ink jet recording comprising at least the coloring composition according to claim 1. 10. The ink composition for ink jet recording according to claim 9, wherein the monovalent counter ion (b) is an ion introduced from alcohol amine. 11. A powder toner composition for electrophotography, which comprises the coloring composition according to claim 1. 12. The powder toner composition for electrophotography according to claim 11, wherein the monovalent counter ion (b) is an ion introduced by an aliphatic amine.