JP2002256194A - Recording liquid for ink jet and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recording liquid for ink jet excellent in water resistance and also in delivering stability at a nozzle. SOLUTION: A mixture of an organic pigment, a water-soluble inorganic salt and a water-soluble solvent is kneaded and subsequently the water-soluble inorganic salt and the water-soluble solvent are removed to give a dispersion of the organic pigment having an average particle size of 10-70 nm. The dispersion of the organic pigment, a dispersion of a resin particle having an average particle size of 50-300 nm and a water-soluble resin are mixed and stirred to give a colored particle comprising the resin particle covered with the organic pigment. The recording liquid for ink jet comprises an aqueous liquid and, dispersed therein, the colored particle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording liquid having excellent water resistance and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, ink jet recording liquids have been disclosed in JP-A-53-61412 and JP-A-54-89.
As disclosed in JP-A-811 and JP-A-55-65269, a dye obtained by dissolving a water-soluble dye such as an acid dye, a direct dye or a basic dye in a glycol solvent and water is often used. However, as the water-soluble dye, a dye having high solubility in water is generally used in order to obtain the stability of the recording liquid. Therefore, the ink jet recorded matter generally has poor water resistance, and there is a problem that spilling water easily causes dye bleeding of a recorded portion.

In order to improve such poor water resistance,
As disclosed in JP-A-56-57862, attempts have been made to change the structure of the dye or to prepare a recording solution having a strong basicity. Also, Japanese Patent Application Laid-Open Nos. 50-49004, 57-36692, and 59-2
As disclosed in JP-A No. 0696 and JP-A-59-146889, attempts have been made to improve the water resistance by making good use of the reaction between the recording paper and the recording liquid. Although these methods have a remarkable effect on specific recording paper, they lack versatility in that they are limited by the recording paper.
When a recording paper other than a specific recording paper is used, a recording liquid using a water-soluble dye often cannot obtain sufficient water resistance of a recorded matter.

As recording liquids having good water resistance, there are those in which an oil-soluble dye is dispersed or dissolved in a high boiling point solvent, and those in which an oil-soluble dye is dissolved in a volatile solvent. Environmentally disliked the emission of
Depending on the case where a large amount of data is recorded or where the apparatus is installed, the necessity of solvent recovery may be a problem. Therefore, in order to improve the water resistance of the recorded matter, a recording liquid in which a pigment is dispersed in an aqueous medium has been developed.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an ink jet recording liquid having good water resistance and good ejection stability at a nozzle.

[0006]

That is, the present invention comprises an aqueous liquid, an organic pigment having an average particle size of 10 to 70 nm, resin particles having an average particle size of 50 to 300 nm, and a water-soluble resin, The present invention relates to a recording liquid for ink jet, wherein the periphery of the resin particles is covered with the organic pigment.

Further, according to the present invention, an organic pigment having an average particle diameter of 10 to 70 nm is kneaded with a mixture of an organic pigment, a water-soluble inorganic salt, and a water-soluble solvent, and then the water-soluble inorganic salt and the water-soluble solvent are removed. The present invention relates to the above-mentioned recording liquid for inkjet.

Further, the present invention relates to the above-mentioned ink jet recording liquid wherein the weight ratio of the resin particles to the organic pigment is 1: 6 to 6: 1.

Further, the present invention provides a method of kneading a mixture of an organic pigment, a water-soluble inorganic salt and a water-soluble solvent, and then removing the water-soluble inorganic salt and the water-soluble solvent to obtain an average particle diameter of 10 to 70.
(A) obtaining a dispersion liquid of an organic pigment having a thickness of nm, and (B) obtaining a concentrated dispersion liquid by dispersing the dispersion liquid of the organic pigment obtained in the step (A) together with a water-soluble resin. The concentrated dispersion obtained in (B) was prepared using
And (C) mixing and stirring with a dispersion liquid of 300 nm resin particles.

Further, the present invention relates to the above-mentioned method for producing an ink jet recording liquid in which colored particles formed by covering an organic pigment around resin particles are dispersed in an aqueous liquid.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION As shown in FIGS. 1 to 3, the colored particles of the present invention have resin particles as nuclei and pigment particles are covered around the resin particles like shells. It is preferable that the resin particles and the organic pigment are mixed at a weight (solid content weight) ratio of 1: 6 to 6: 1. Further, it is preferable that the ink jet recording liquid contains 0.1 to 10% by weight of a solid content of colored particles in which an organic pigment is covered around resin particles.

The resin particles have an average particle size of 50 to 300 nm,
It preferably has a size of 50 to 200 nm, and is preferably formed of an alkyl ester of an unsaturated carboxylic acid such as acrylic acid, methacrylic acid, itaconic acid, or maleic acid, an aryl ester, an arylalkyl ester, styrene, α-methylstyrene, vinyltoluene, or the like. , Carboxyl group, sulfonic group, sulfate group, phosphate group, etc. or their sodium salt, potassium salt, lower amine salt, alkylamine, alkanolamine, primary amine, secondary amine, tertiary amine Emulsion polymerization of monomers having a cationic hydrophilic group such as a quaternary ammonium group, a pyridium group or the like, or a nonionic hydrophilic group such as a hydroxyl group, a carboxamide group, a polyether glycol group, an ether group, etc. It can be obtained by: If necessary, a neutralizing agent such as ammonia, amine, or inorganic alkali can be appropriately added to the ink jet recording liquid of the present invention.

As the organic pigment, one or more selected from the group consisting of quinacridone organic pigments, phthalocyanine organic pigments, azo organic pigments, isoindolinone organic pigments, and imidazolone organic pigments are preferably used. Can be The average particle size of the organic pigment is preferably smaller than that of the resin particles. The average particle size of the primary particles of the organic pigment measured using a transmission electron microscope is 10 to 70 nm, and more preferably 1 to 70 nm.
It is preferably from 0 to 40 nm.

Specific examples of the organic pigment include insoluble azo pigments such as toluidine red, toluidine maroon, hansa yellow, benzidine yellow, and pyrazolone red; soluble azo pigments such as lithol red, helio bordeaux, pigment scarlet, and permanent red 2B; Derivatives from vat dyes such as phthalocyanine blue, phthalocyanine blue, phthalocyanine green, quinacridone pigments such as quinacridone red and quinacridone magenta, perylene pigments such as perylene red and perylene scarlet; Isoindolinone pigments such as indolinone yellow, isoindolinone orange, benzimidazolone yellow, benzimidazolone orange,
Imidazolone pigments such as benzimidazolone red, pyranthrone pigments such as pyranthrone red and pyranthrone orange, thioindigo pigments, condensed azo pigments,
Other pigments such as thioindigo pigments, flavanthrone yellow, acylamide yellow, quinophthalone yellow, nickel azo yellow, copper azomethine yellow, perinone orange, anthrone orange, dianthraquinonyl red, and dioxazine violet can be exemplified.

In addition, the organic pigment is used as a color index (C.I.
I.) Indicated by number, CI Pigment Yellow 12,
13, 14, 17, 20, 24, 74, 83, 869
3, 109, 110, 117, 120, 125, 13
7, 138, 147, 148, 151, 153, 15
4, 166, 168, CI Pigment Orange 16,3
6, 43, 51, 55, 59, 61, CI Pigment Red 9, 48, 49, 52, 53, 57, 97, 12
2,123,149,168,175,176,17
7, 180, 192, 215, 216, 217, 22
0, 223, 224, 226, 227, 228, 23
8, 240, CI Pigment Violet 19, 23,
29, 30, 37, 40, 50, CI Pigment Blue 15, 15: 1, 15: 4, 15: 6, 22, 60, 6
4, CI Pigment Green 7, 36, CI Pigment Brown 23, 25, 26 and the like.

The ink-jet recording liquid of the present invention comprises a dispersion liquid of an organic pigment obtained by finely dispersing an organic pigment in an aqueous liquid together with a dispersant and, if necessary, a compound represented by the following general formula: It is manufactured by mixing and stirring a dispersion liquid of 300 nm resin particles. P- [XYZN (R ¹ ) R ² ] n (where P is an organic dye residue, a heterocyclic residue or an aromatic polycyclic compound residue, and X is S, C , N, O, H, a divalent linking group consisting of a chemically rational combination of 2 to 15 atoms selected from Y, Y is a direct bond, -NR-
(Where R is H or an alkyl group having 1 to 18 carbon atoms),
A divalent linking group selected from —O—, Z is an alkylene group having 1 to 6 carbon atoms, R ¹ and R ² are each independently an alkyl group having 1 to 18 carbon atoms which may be substituted, or R ¹
And R ² may form a heterocyclic ring, which may have a substituent, and n represents an integer of 1 to 3. )

As the dispersant, various surfactants, low-molecular-weight dispersants, resin-based dispersants having a hydrophilic functional group and a hydrophobic functional group, and the like are used. As the surfactant, anionic, nonionic, cationic or zwitterionic surfactants can be used.

Examples of the anionic activator include fatty acid salts, alkyl sulfate salts, alkyl aryl sulfonates, alkyl naphthalene sulfonates, dialkyl sulfonates, dialkyl sulfosuccinates, alkyl diaryl ether disulfonates, and alkyl phosphoric acids. Salt, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl aryl ether sulfate, naphthalenesulfonic acid formalin condensate, polyoxyethylene alkyl phosphate ester salt, glycerol borate fatty acid ester, polyoxyethylene glycerol fatty acid ester, etc. Can be illustrated.

Examples of the nonionic activator include polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, polyoxyethylene oxypropylene block copolymer, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, Examples thereof include glycerin fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene alkylamine, fluorine-based, and silicon-based nonionic activators.

Examples of the cationic activator include an alkylamine salt, a quaternary ammonium salt, an alkylpyridinium salt, an alkylimidazolium salt and the like. Examples of amphoteric surfactants include alkyl betaines, alkylamine oxides, phosphadylcholines, and the like. Fine dispersion of organic pigments in water can be performed by sand mill, ball mill,
It can be performed by a method using a disperser such as an attritor, a paint shaker, a pearl mill, an ultrasonic disperser, and the like.

In order to further reduce the size of the organic pigment, the organic pigment is kneaded with a water-soluble inorganic salt, a water-soluble solvent and, if necessary, a compound represented by the following general formula, and dispersed in water. It is preferable to produce a dispersion of the organic pigment by removing the water-soluble solvent. In this method, a water-soluble inorganic salt is used as a crushing aid, and primary particles of an organic pigment are mechanically finely divided. Specifically, a small amount of a water-soluble solvent is added as a wetting agent to a mixture of an organic pigment, a water-soluble inorganic salt, and, if necessary, a compound of the following general formula. Stir with a mixer or the like to form a slurry. Next, filtration and washing of the slurry are repeated to remove the water-soluble inorganic salt and the water-soluble solvent.

P- [XYZN (R ¹ ) R ² ] n (wherein, P is an organic dye residue, a heterocyclic residue or an aromatic polycyclic compound residue, and X is A divalent linking group consisting of a chemically rational combination composed of 2 to 15 atoms selected from S, C, N, O and H, Y is a direct bond, -NR-
(Where R is H or an alkyl group having 1 to 18 carbon atoms),
A divalent linking group selected from —O—, Z is an alkylene group having 1 to 6 carbon atoms, R ¹ and R ² are each independently an alkyl group having 1 to 18 carbon atoms which may be substituted, or R ¹
And R ² may form a heterocyclic ring, which may have a substituent, and n represents an integer of 1 to 3. )

Specifically, X is -SO _2- , -C
_{O -, - CH 2 -,} - CH 2 S -, - CH 2 O -, - O
-, - COO -, - NH -, - CH 2 NHCOCH-,
Or a combination thereof, of which -SO
_{2 -, -CO -, - CH} 2 - is preferred. N, O, and S are examples of the constituent elements other than carbon of the heterocyclic ring formed by R ¹ and R ² . The substituent-[XY-
Specific examples of ZN (R ¹ ) R ² ] n include the following.

[0024]

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The organic pigment and P in the above general formula compound, that is, the organic dye residue, the heterocyclic residue or the aromatic polycyclic compound residue are usually combined in the same system in view of the hue. In particular, it is preferable to combine a phthalocyanine-based residue for a blue phthalocyanine-based pigment, a quinacridone-based residue for a red quinacridone-based pigment, and a benzimidazole-based residue for a yellow benzimidazole-based pigment, They do not have to match. It is preferable that the above-mentioned general formula compound is partially soluble in a water-soluble solvent used as a wetting agent at the time of kneading, and when not soluble, a dilute acid is added to the general formula compound to carry out a neutralization treatment or the like. Preferably, it is soluble. Acetic acid, hydrochloric acid, sulfuric acid and the like can be used as the acid. Further, two or more of the above general formula compounds may be used in combination.

The water-soluble inorganic salts include sodium chloride,
Potassium chloride and the like can be mentioned. Although the water-soluble solvent is not particularly limited, a solvent having a high boiling point is preferable from the viewpoint of safety because the temperature rises during the kneading process and the solvent is easily evaporated. For example, 2- (methoxymethoxy) ethanol, 2-butoxyethanol, 2- (isopentyloxy) ethanol, 2- (hexyloxy) ethanol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol , Triethylene glycol monomethyl ether, liquid polyethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl Ether, low molecular weight polypropylene glycol and the like are used.

When kneading the organic pigment with a water-soluble inorganic salt, a water-soluble solvent and, if necessary, a compound of the following general formula, additives such as a dispersant and a plasticizer may be used in combination. Further, two or more kinds of organic pigments may be mixed and finely dispersed. Dispersion of obtained organic pigment and average particle size of 50 to 300
By mixing and stirring the dispersion of the resin particles having a diameter of 10 nm with water, an aqueous solvent, and a dispersant as necessary, the mixture shown in FIG.
As shown in (2) and (2), an ink jet recording liquid is obtained in which colored particles formed by covering an organic pigment around resin particles are dispersed in an aqueous liquid. The mixing and stirring can be performed by a mixing stirrer such as a high-speed disperser or an emulsifier in addition to a stirrer using a normal blade.

The ink-jet recording liquid is prepared by dispersing a dispersion of an organic pigment together with a water-soluble resin, water and a dispersant, if necessary, using a disperser such as a sand mill, a homogenizer, a ball mill, a paint shaker, or an ultrasonic disperser. To prepare a dispersion in a concentrated state in advance, and then to prepare an average particle diameter of 50%.
It can be produced by adding a dispersion liquid of resin particles having a size of about 300 nm, water and additives as needed, and mixing and stirring. The recording liquid for inkjet has a pore size of 1 μm
It is preferable to filter with a filter having a size of 0.8 μm or less, more preferably 0.45 μm or less. Prior to the filtration, the particles having a large particle size can be removed by centrifugation, whereby clogging in the filtration can be reduced and the service life of the filter can be prolonged.

The water-soluble resin can be used to firmly fix the colored particles. Examples of the water-soluble resin include resins soluble in water, such as acrylic, styrene-acryl, polyester, polyamide, and polyurethane. The water-soluble resin is preferably used in the recording liquid in an amount of 5% by weight or less. 5% by weight
If used in excess of this, the ejection stability of the recording liquid may be reduced.

The ink-jet recording liquid of the present invention uses an aqueous liquid containing water and, if necessary, an aqueous solvent as a medium. As the water, ion-exchanged water or distilled water from which metal ions and the like have been removed is used. The aqueous solvent is used alone or in combination with the recording liquid to prevent drying of the recording liquid at the nozzle portion, solidification of the recording liquid, and stable ejection of the recording liquid and drying of the nozzle over time. It can be used in the range of 50% by weight.

As the aqueous solvent, ethylene glycol,
Diethylene glycol, propylene glycol, triethylene glycol, polyethylene glycol, glycerin, tetraethylene glycol, dipropylene glycol, ketone alcohol, diethylene glycol monobutyl ether, ethylene glycol monobutyl ether,
Examples include ethylene glycol monoethyl ether, 1,2-hexanediol, N-methyl-2-pyrrolidone, substituted pyrrolidone, 2,4,6-hexanetriol, tetrafurfuryl alcohol, and 4-methoxy-4-methylpentanone. .

Further, alcohols such as methanol, ethanol and isopropyl alcohol can be used for the purpose of speeding up drying of the recording liquid on paper. When the printing medium of the recording liquid is a permeable material such as paper, a penetrant can be added in order to stop the penetration of the recording liquid into the paper and speed up the apparent dryness. As the penetrant, use may be made of glycol ethers such as diethylene glycol monobutyl ether exemplified as aqueous solvents, alkylene glycol, polyethylene glycol monolauryl ether, sodium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium oleate, sodium dioctylsulfosuccinate and the like. it can. These have a sufficient effect when used in an amount of 5% by weight or less of the recording liquid. If the amount is more than 5% by weight, bleeding of printing and paper loss (print through) occur, which is not preferable.

The recording liquid of the present invention may contain a fungicide in an amount of 0.05 to 1.0% by weight of the recording liquid in order to prevent the occurrence of mold. Examples of fungicides include sodium dehydroacetate, sodium benzoate, sodium pyridinethione-1-oxide, zinc pyridinethione-1.
-Oxide, 1,2-benzisothiazolin-3-one, amine salt of 1-benzisothiazolin-3-one and the like are used.

Further, a chelating agent can be used in the range of 0 to 0.5% by weight of the recording liquid in order to prevent the deposition of metal at the nozzle portion and the precipitation of insoluble matters in the recording liquid. . The chelating agent blocks metal ions in the recording liquid, and specifically includes ethylenediaminetetraacetic acid, sodium salt of ethylenediaminetetraacetic acid, diammonium salt of ethylenediaminetetraacetic acid, and ethylenediaminetetraacetic acid. Acid ammonium tetraammonium salt.

Further, in order to adjust the pH of the recording liquid and obtain stability of the recording liquid or stability with the recording liquid pipe in the recording apparatus, a pH adjuster such as an amine, an inorganic salt or ammonia, and a buffer such as phosphoric acid. Liquids can be used. Further, an antifoaming agent can be added in order to prevent the circulation and movement of the recording liquid or the generation of bubbles during the production of the recording liquid. Further, for the purpose of adjusting the hue, imparting the density, and the like, the dye can be used in such a form that there is no problem in water resistance and light resistance.
Since the use of a dye may deteriorate the dispersion stability of the pigment, the amount of the pigment used is 40% by weight or less of the pigment,
It is preferable to keep the content at 5% by weight or less. As dyes,
Water-insoluble dyes such as disperse dyes and oil-soluble dyes, dyes in which direct dyes, acid dyes, basic dyes and the like are insolubilized by lake formation, reactive dyes, metal-containing dyes, and the like are used. The dye
Purified dyes from which inorganic salts have been removed are preferred.

As other additives, urea, dimethyl urea and the like can be added. The recording liquid is preferably adjusted as a liquid having a viscosity of 0.8 to 15 cps (25 ° C.), depending on the type of the recording apparatus. Surface tension is 25-6
0 dyn / cm is preferred. The pH is not particularly limited, but is in the range of 4 to 12, preferably 7 to 10 neutral to weakly alkaline.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments.
Parts and% in the examples indicate parts by weight and% by weight. Example 1 220 parts of quinacridone-based red pigment ("Poster Palm Pink E" manufactured by Hoechst), 2200 parts of sodium chloride, and 160 parts of polyethylene glycol ("Polyethylene Glycol 300" manufactured by Tokyo Kasei) were mixed with 1 gallon kneader made of stainless steel (Inoue). 6)
Kneaded for hours. Next, the mixture was poured into 2.5 L of warm water and stirred for about 1 hour with a high-speed mixer while heating to about 80 ° C. to form a slurry. Filtration and washing were repeated eight times to remove sodium chloride and polyethylene glycol, thereby obtaining an aqueous red pigment slurry I having a solid content of 40%.

The following raw materials were placed in a sand mill and dispersed for 2 hours to prepare a concentrated recording liquid for inkjet. Aqueous red pigment slurry I (solid content 50%) 0.0 part Acrylic resin aqueous solution 3.0 parts (Johncryl 62, manufactured by Johnson Polymer, solid content 31.0%) Dimethylaminoethanol 0.1 part Nonionic Activator ("Emulgen A-90" manufactured by Kao Corporation) 1.0 part Purified water 50.0 parts Glycerin 6.0 parts

After mixing the following raw materials, the mixture was filtered through a 1 μm membrane filter and further filtered through a 0.45 μm membrane filter to produce a recording liquid. Observation of the obtained recording liquid with a transmission electron microscope revealed a dispersion form as shown in FIGS. 13.5 parts of the above-mentioned concentrated recording liquid for inkjet non-ionic activator ("Emulgen A-90" manufactured by Kao Corporation) 0.2 part Acrylic resin emulsion 2.5 parts ("W-251" manufactured by Nippon Polymer Co., Ltd., solid content) 40%) Ethylene glycol 10.0 parts Antifungal agent ("Sodium Omazine" manufactured by Aurin Chemical Co.) 0.15 parts Sodium salt of ethylenediaminetetraacetylic acid 0.02 parts Purified water 63.53 parts

Example 2 Crude copper phthalocyanine pigment ("Copper phthalocyanine" manufactured by Toyo Ink Mfg. Co., Ltd.) 250
Parts, 2500 parts of sodium chloride, a blue pigment dispersant (P-
25 parts of [CH ₂ NH (CH ₂ ) ₄ N (CH ₃ ) ₂ ] ₃ , P is a copper phthalocyanine residue and polyethylene glycol (“Polyethylene glycol 30” manufactured by Tokyo Chemical Industry Co., Ltd.)
0 ") 160 parts were charged into a stainless steel 1 gallon kneader (manufactured by Inoue Seisakusho) and kneaded for 3 hours. Next, this mixture was poured into 2.5 L of warm water, and stirred for about 1 hour with a high-speed mixer while heating to about 80 ° C. to form a slurry. Filtration and washing were repeated five times to remove sodium chloride and polyethylene glycol, thereby obtaining an aqueous blue pigment slurry II having a solid content of 50%.

The following materials were placed in a sand mill and dispersed for 3 hours to prepare a concentrated recording liquid for inkjet. Aqueous blue pigment slurry II (solid content 50%) 30.0 parts Acrylic resin aqueous solution 3.0 parts ("Johncryl 61J" manufactured by Johnson Polymer, solid content 31.0%) Nonionic activator (manufactured by Kao Corporation) Emulgen 420 ") 1.0 part Purified water 50.0 parts Glycerin 6.0 parts

After mixing the following raw materials, the mixture was filtered through a 1 μm membrane filter and further filtered through a 0.45 μm membrane filter to produce a recording liquid. 13.5 parts of the above-mentioned concentrated recording liquid for inkjet non-ionic activator (“Emulgen 420” manufactured by Kao Corporation) 0.2 parts Acrylic resin emulsion 2.2 parts (“W-251” manufactured by Nippon Polymer Co., Ltd., solid content 40) %) Ethylene glycol 10.0 parts Antifungal agent ("Sodium Omazine" manufactured by Orin Chemical Co., Ltd.) 0.15 parts Sodium salt of ethylenediaminetetraacetic acid 0.02 parts Purified water 63.53 parts

Example 3 Crude copper phthalocyanine pigment 2
Benzimidazolone yellow pigments in place of 50 parts (Hoechst "Posters Palm Yellow H3G") using 260 parts of a blue pigment dispersing agent 25 parts of a yellow pigment dispersant in place of (P- [CH ₂ NH (CH ₂ ) ₄ N (C
In the same manner as in Example 2, an ink jet recording liquid was obtained using 15 parts of H ₃ ) ₂ ] ₃ and P as a benzimidazole residue.

Example 4 Crude copper phthalocyanine pigment ("Copper phthalocyanine" manufactured by Toyo Ink Mfg. Co., Ltd.) 250
Parts, 900 parts of sodium chloride, a blue pigment dispersant (P-
[CH ₂ NH (CH ₂ ) ₄ N (CH ₃ ) ₂ ] ₃ , P is a copper phthalocyanine residue (25 parts), acrylic oligomer (“Johncryl 682” manufactured by Johnson Wax) 1
00 parts and diethylene glycol (Tokyo Kasei) 1
60 parts were charged in the same kneader as in Example 1 and kneaded for 2 hours. Next, an aqueous blue pigment slurry IV having a solid content of 50% was obtained in the same manner as in Example 1.

The following materials were placed in a sand mill and dispersed for 4 hours to prepare a concentrated recording liquid for inkjet. Aqueous blue pigment slurry IV (solid content 50%) 30.0 parts Acrylic resin emulsion 2.3 parts (Nippon Polymer "F-157" solid content 40%) Dispersant (Zeneca "Solsperse 27000") 0. 5 parts Purified water 74.0 parts Glycerin 5.8 parts Dimethylethanolamine 0.1 part

After mixing the following raw materials, the mixture was filtered through a 3 μm membrane filter, subsequently filtered through a 1 μm membrane filter, and further filtered through a 0.45 μm membrane filter to produce a recording solution. 13.7 parts of the above-mentioned concentrated recording liquid for inkjet nonionic activator ("Emulgen 420" manufactured by Kao Corporation) 0.2 parts Acrylic resin emulsion 2.2 parts ("W-251" manufactured by Nippon Polymer Co., Ltd., solid content 40) %) Diethylene glycol 9.0 parts Fungicide ("Sodium Omazine" manufactured by Olin Chemical Co.) 0.15 parts Sodium salt of ethylenediaminetetraacetylic acid 0.03 parts Purified water 63.50 parts

Example 5 250 parts of quinacridone red pigment ("Poster Palm Pink E" manufactured by Hoechst), 2500 parts of sodium chloride, and 160 parts of polyethylene glycol ("polyethylene glycol 300" manufactured by Tokyo Kasei)
The part was charged into a stainless steel 1 gallon kneader (manufactured by Inoue Seisakusho) and kneaded for 3 hours. Next, add 2.5 L of this mixture
And heated to about 80 ° C. while stirring at about 80 ° C. with a high speed mixer for about 1 hour to form a slurry. Filtration and washing were repeated five times to remove sodium chloride and polyethylene glycol. An aqueous red pigment slurry V was obtained.

The following materials were placed in a sand mill and dispersed for 4 hours to prepare a concentrated recording liquid for inkjet. Aqueous red pigment slurry V (solid content 50%) 30.0 parts Acrylic resin aqueous solution 3.0 parts ("Johncryl 62" manufactured by Johnson Polymer, solid content 31.0%) Nonionic activator (manufactured by Kao Corporation) Emulgen A-90 ") 1.0 part Purified water 50.0 parts Glycerin 6.0 parts

After mixing the following raw materials, the mixture was filtered through a 0.45 μm membrane filter to produce a recording solution. 13.5 parts of the above-mentioned concentrated recording liquid for inkjet non-ionic activator ("Emulgen A-90" manufactured by Kao Corporation) 0.2 part Acrylic resin emulsion 2.4 parts ("W-251" manufactured by Nippon Polymer Co., solid content) 40%) Ethylene glycol 10.0 parts Fungicide (Proxel GXL manufactured by Zeneca) 0.15 parts Sodium salt of ethylenediaminetetraacetic acid 0.02 parts Purified water 63.53 parts

Comparative Example 1 The following materials were placed in a paint shaker and dispersed for 9 hours to prepare a concentrated recording liquid for inkjet. Quinacridone red pigment 15.0 parts ("Poster Palm Pink E" manufactured by Hoechst) Acrylic resin aqueous solution 3.0 parts ("Johncryl 62" manufactured by Johnson Polymer, solid content 31.0%) Nonionic activator ( 1.0 part of purified water 50.0 parts of glycerin 6.0 parts After mixing the following raw materials, the mixture was filtered through a 1 μm membrane filter to produce a recording liquid. The filtration amount with a 1 μm membrane filter was 1/3 or less of that of the example.
Also, it was very difficult to filter with a 0.45 μm filter. The above-mentioned concentrated recording liquid for inkjet 13.5 parts Nonionic activator ("Emulgen A-90" manufactured by Kao Corporation) 0.2 part Acrylic resin aqueous solution 2.3 parts ("Johncryl 62" manufactured by Johnson Polymer, solid content) 31.0%) Ethylene glycol 10.0 parts Fungicide (“Proxel GXL” manufactured by Zeneca) 0.15 parts Sodium salt of ethylenediaminetetraacetylic acid 0.02 parts Purified water 63.53 parts

Example 6 Instead of 260 parts of a benzimidazolone-based yellow pigment, 280 parts of an azo-based yellow pigment ("Hanzaza brilliant yellow 9GX" manufactured by Hoechst) was used, and a solid content of 50% was obtained in the same manner as in Example 3. % Aqueous yellow pigment slurry VI was obtained. Next, the following raw materials were placed in a sand mill and dispersed for 1 hour to prepare a concentrated recording liquid for inkjet. Aqueous yellow pigment slurry VI (solid content 50%) 55.0 parts Acrylic resin aqueous solution 7.0 parts ("Johncryl 61J" manufactured by Johnson Polymer, solid content 31.0%) Nonionic activator (manufactured by Kao Corporation) Emulgen A-90 ") 4.0 parts Purified water 56.0 parts Diethylene glycol monobutyl ether 3.0 parts N-methyl-2-pyrrolidone 3.0 parts 2,4,7,9-tetramethyl-5-decyne-4 1.0 part of ethylene glycol 1.0 part After mixing the following raw materials, the mixture was filtered through a 1 μm membrane filter, followed by filtration through a 0.45 μm membrane filter to produce a recording liquid. Concentrated recording liquid for ink jet 13.0 parts Dispersant (Solsperse 27000, manufactured by Zeneca)) 0.2 parts Acrylic resin emulsion 3.0 parts (Emapoly TYN-40, manufactured by Gifu Shellac Co., solid content 44) 0.8%) Diethylaminoethanol 0.2 part Diethylene glycol 22.5 parts Antifungal agent (“Proxel GXL” manufactured by Zeneca) 0.15 part Ethylenediaminetetraacetic acid sodium salt 0.02 part Purified water 63.53 parts 2, 0.1 parts of 4,7,9-tetramethyl-5-decyne-4,7-diol

Example 7 Crude copper phthalocyanine pigment 2
280 instead of 50 parts of a phthalocyanine blue pigment (“Lionol Blue KLH-T” manufactured by Toyo Ink Mfg. Co., Ltd.)
In the same manner as in Example 4, an aqueous blue pigment slurry VII having a solid content of 50% was obtained. Next, the following raw materials were placed in a sand mill and dispersed for 3 hours to prepare a concentrated recording liquid for inkjet. Aqueous blue pigment slurry VII (solid content 50%) 18.0 parts Acrylic resin aqueous solution 3.8 parts ("Johncryl 62" manufactured by Johnson Polymer, solid content 31.0%) Nonionic activator (manufactured by Kao Corporation) Emulgen A-90 ") 3.0 parts Purified water 74.5 parts Ethylene glycol 6.0 parts

After mixing the following raw materials, the mixture was filtered through a 1 μm membrane filter, and then filtered through a 0.45 μm membrane filter to produce a recording liquid. 13.9 parts of the above-described concentrated recording liquid for inkjet 13.9 parts Dispersant ("Solsperse 27000" manufactured by Zeneca)) 0.3 parts Acrylic resin emulsion 2.1 parts ("W-251" manufactured by Nippon Polymer Co., solid content 40%) Glycerin 24.0 parts Fungicide (“Sodium Omazine” manufactured by Olin Chemical Co.) 0.15 parts Purified water 63.50 parts

Comparative Example 2 The following materials were placed in a sand mill and dispersed for 2 hours to prepare a concentrated recording liquid for inkjet. Phthalocyanine-based blue pigment 8.0 parts (Toyo Ink Mfg. Co., Ltd. "Lionol Blue KLH-T") Acrylic resin aqueous solution 3.8 parts (Johnson Polymer Co., Ltd. "John Krill 62", solid content 31.0%) Dispersant (“SOLSPERS 27000” manufactured by Zeneca)) 4.0 parts Purified water 82.5 parts Ethylene glycol 6.0 parts

After mixing the following raw materials, the mixture was filtered through a 1 μm membrane filter, and a filter three times as large as that in the example was used. Also, it was very difficult to filter with a 0.45 μm membrane filter. 13.9 parts of the above-described concentrated recording liquid for inkjet 13.9 parts Dispersant ("Solsperse 27000" manufactured by Zeneca)) 0.3 parts Acrylic resin emulsion 2.1 parts ("W-251" manufactured by Nippon Polymer Co., solid content 40%) Glycerin 24.0 parts Antifungal agent (“Sodium Omazine” manufactured by Olin Chemical Co.) 0.15 parts

Example 8 The following raw materials were placed in a pearl mill and dispersed for 3 hours to prepare a concentrated recording liquid for inkjet. Azo-based yellow pigment 25.0 parts (Toyo Ink Mfg. Co., Ltd. "Lionol Yellow 22-2845") Dispersant (Zeneca Co., Ltd. "Solsperse 27000")) 0.3 parts Acrylic resin aqueous solution 3.0 parts (Johnson Polymer) "Joncryl 62", solid content 31.0%) Dimethylaminoethanol 0.1 part Nonionic activator ("Emulgen A-90", Kao Corporation) 1.3 parts Purified water 75.0 parts Ethylene glycol 6.0 copies

After mixing the following raw materials, the mixture was filtered through a 1 μm membrane filter, and then filtered through a 0.45 μm membrane filter to produce a recording liquid. Observation of the obtained recording liquid with a transmission electron microscope showed a dispersion form as shown in FIG. 13.5 parts of the above-mentioned concentrated recording liquid for inkjet non-ionic activator ("Emulgen A-90" manufactured by Kao Corporation) 0.2 part Acrylic resin emulsion 2.5 parts ("W-251" manufactured by Nippon Polymer Co., Ltd., solid content) 40%) Ethylene glycol 10.0 parts Antifungal agent ("Sodium Omazine" manufactured by Aurin Chemical Co.) 0.15 parts Sodium salt of ethylenediaminetetraacetylic acid 0.02 parts Purified water 63.53 parts

[Example 9] Crude copper phthalocyanine pigment ("Copper phthalocyanine" manufactured by Toyo Ink Mfg. Co., Ltd.) 250
Parts, 2500 parts of sodium chloride and polyethylene glycol (“Polyethylene glycol 30” manufactured by Tokyo Chemical Industry Co., Ltd.)
0 ") 160 parts were charged into a stainless steel 1 gallon kneader (manufactured by Inoue Seisakusho) and kneaded for 3 hours. Next, this mixture was poured into 2.5 L of warm water, and stirred for about 1 hour with a high-speed mixer while heating to about 80 ° C. to form a slurry. Filtration and washing were repeated five times to remove sodium chloride and polyethylene glycol, thereby obtaining an aqueous blue pigment slurry IX having a solid content of 50%. The following materials were placed in a pearl mill and dispersed for 3 hours to prepare a concentrated recording liquid for inkjet. Aqueous blue pigment slurry IX (50% solids) 30.0 parts blue pigment dispersing agent (P- _{[CH 2 NH (CH 2) 4} N (CH 3) 2 ] _3, P is a copper phthalocyanine residue) 1.4 Part Dispersant (“Solsperse 27000” manufactured by Zeneca)) 0.3 part Acrylic resin aqueous solution 3.0 parts (“Johncryl 61J” manufactured by Johnson Polymer, solid content 31.0%) Nonionic activator (Kao 1.0 part of purified water 50.0 parts Glycerin 6.0 parts

After mixing the following raw materials, the mixture was filtered through a 1 μm membrane filter and further filtered through a 0.45 μm membrane filter to produce a recording liquid. 13.5 parts of the above-mentioned concentrated recording liquid for inkjet nonionic surfactant ("Emulgen 420" manufactured by Kao Corporation) 0.2 part Acrylic resin emulsion 2.4 parts ("W-251" manufactured by Nippon Polymer Co., Ltd., solid content 40) %) Ethylene glycol 10.0 parts Antifungal agent ("Sodium Omazine" manufactured by Orin Chemical Co., Ltd.) 0.13 parts Sodium salt of ethylenediaminetetraacetylic acid 0.04 parts Purified water 63.33 parts

The recording liquids obtained in Examples and Comparative Examples were evaluated for filterability, viscosity, average particle size, printing state, water resistance, transparency, and jet characteristics. Table 1 shows the results. In addition,
The evaluation was performed as follows. Further, the recording liquid obtained in the example was spontaneously dissolved after storage at -40 ° C. for one week, but the initial viscosity was maintained and stable ejection characteristics were exhibited. Furthermore, the recording liquid obtained in the example was stored in a thermostat at 60 ° C. for one month, but the initial viscosity was maintained and stable ejection characteristics were exhibited.

[Filterability] 0.4 mm of diameter 90 mm per minute
The amount that could be filtered through a 5 μm membrane filter was measured. [Viscosity] Viscometer (Viscomate VM-1 manufactured by Yamaichi Electric Co., Ltd.)
A)) at 25 ° C. [Average Particle Size] The particle size distribution of the recording liquid was measured with a laser diffraction type particle size distribution meter (“DSL-700” manufactured by Otsuka Electronics Co., Ltd.), and the average particle size was determined.

[Printing state] The recording liquid was put into a cartridge of an ink jet printer (“HG5130” manufactured by Seiko Epson Corporation) and recorded on plain paper (“K” manufactured by Xerox Corporation), and the printed state of the recorded matter was visually evaluated. . Good: No missing dots, no disturbance in direction. Poor: Missing dots, disturbed direction. [Water resistance] The recorded matter recorded on plain paper ("K" manufactured by Xerox Corporation) was dried, and then immersed in water for 1 minute. Good: No bleeding of ink, no flow. Poor: ink bleeding, runoff.

[Transparency] The transparency when the ink was spread on an OHP sheet for inkjet using a 1.5 mil applicator was visually evaluated. Good: Transparent. Poor: no transparency. [Ejection Characteristics] The ejection state of the nozzles during continuous printing was evaluated by recorded matter. Good: Continuous printing was accurately performed at a predetermined position. Defective: Despite continuous printing, a defect occurs on the way, or printing is not performed at a predetermined position.

[0064]

[Table 1]

[0065]

According to the present invention, it is possible to obtain a recording liquid which gives a recorded matter having good water resistance while using water as a medium. As a result, the restrictions on the recording medium are greatly reduced, and the use of the recording medium in the field where the shortage of water resistance often occurs due to the influence of the recording medium in the past can be expanded. Specifically, the ink jet recording liquid of the present invention can be used in fields such as creation of documents in offices, marking of cardboard, numbering, and bar code recording.

[Brief description of the drawings]

FIG. 1 is an electron micrograph of a recording solution of Example 1.

FIG. 2 is an electron micrograph of the recording liquid of Example 1.

FIG. 3 is an electron micrograph of a recording solution of Example 8.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tsutomu Fujigamori 2-3-13 Kyobashi, Chuo-ku, Tokyo Inside Toyo Ink Manufacturing Co., Ltd. (72) Inventor Kiyoji Ma 2-3-3 Kyobashi, Chuo-ku, Tokyo No. 13 F-term in Toyo Ink Manufacturing Co., Ltd. (reference) 2C056 EA13 FC01 4G035 AB43 4J039 AD00 AD03 AD10 AE04 AE08 BA15 BE01 BE12 BE22 CA06 EA38 EA41 GA24

Claims (5)

[Claims] 1. An aqueous liquid, having an average particle size of 10 to 70 nm.
An ink-jet recording liquid comprising: an organic pigment described above, resin particles having an average particle diameter of 50 to 300 nm, and a water-soluble resin, wherein the resin pigment is covered with the organic pigment. 2. An organic pigment having an average particle size of 10 to 70 nm,
2. The ink jet recording liquid according to claim 1, wherein a mixture of an organic pigment, a water-soluble inorganic salt, and a water-soluble solvent is kneaded, and then the water-soluble inorganic salt and the water-soluble solvent are removed. 3. The weight ratio of the resin particles to the organic pigment is 1: 6 to
3. The ink jet recording liquid according to claim 1, wherein the ratio is 6: 1. 4. A dispersion of an organic pigment having an average particle size of 10 to 70 nm obtained by kneading a mixture of an organic pigment, a water-soluble inorganic salt, and a water-soluble solvent, and then removing the water-soluble inorganic salt and the water-soluble solvent. A step of obtaining a liquid (A); a step (B) of dispersing the dispersion of the organic pigment obtained in the step (A) together with a water-soluble resin to obtain a concentrated dispersion; And (C) mixing and stirring the dispersion in a concentrated state with a dispersion of resin particles having an average particle diameter of 50 to 300 nm. 5. The method for producing an ink jet recording liquid according to claim 4, wherein the colored particles comprising the resin particles covered with an organic pigment are dispersed in an aqueous liquid.