JP2023019647A - Ink and inkjet recording device - Google Patents

Abstract

To provide an ink that is excellent in dischargeability during ink filling, defoamability of ink, discharge stability, and ink passability.SOLUTION: An ink is used in an inkjet recording device having a filter for an ink channel, the ink containing water, a colorant, a silicone surfactant, and silicone compound particles. The silicone compound particles have a volume average size (D50) of 1.01 μm-5.00 μm. The content of the silicone compound particles is 0.01 mass%-0.20 mass%.SELECTED DRAWING: Figure 1

Description

The present invention relates to ink and an inkjet recording apparatus.

The ink jet recording method has the advantage that the process is simpler than the other recording methods, so full-color printing is easy, and high-resolution images can be obtained even with an apparatus having a simple configuration. Dye-based inks in which various water-soluble dyes are dissolved in water or a mixture of water and a water-soluble humectant are used as inkjet inks.

In recent years, regulations on fluorosurfactants have become stricter due to the tightening of environmental regulations. The use of fluorosurfactants is often restricted. Fluorine-based surfactants have excellent properties such as good wettability to substrates and good defoaming, so there is a problem that it is difficult to select alternative materials. Considering the environment, hydrocarbon-based surfactants have less environmental impact than fluorine-based or silicone-based surfactants. Therefore, it has been proposed to use a surfactant having an acetylene structure as a hydrocarbon-based surfactant to improve wettability and foamability (see Patent Document 1). However, even if a surfactant having an acetylene structure is used, the antifoaming property is not sufficiently satisfactory.

SUMMARY OF THE INVENTION An object of the present invention is to provide an ink which is excellent in dischargeability, ink defoaming property, discharge stability, and ink permeability at the time of ink filling.

The ink of the present invention as a means for solving the above-mentioned problems is an ink used in an ink jet recording apparatus having a filter in the ink channel, comprising water, a coloring material, a silicone surfactant, and silicone compound particles. containing, the volume average particle diameter (D ₅₀ ) of the silicone compound particles is 1.01 μm to 5.00 μm, and the content of the silicone compound particles is 0.01% by mass to 0.20% by mass. Characterized by

ADVANTAGE OF THE INVENTION According to this invention, the ink which is excellent in the dischargeability at the time of ink filling, the defoaming property of an ink, discharge stability, and ink liquid permeability can be provided.

FIG. 1 is a perspective view showing an example of the inkjet recording apparatus of the present invention. FIG. 2 is a sectional view showing an example of the inkjet recording apparatus of the present invention. FIG. 3 is a schematic diagram showing part of the inkjet recording apparatus of FIG. FIG. 4 is a schematic diagram showing an example of an ink cartridge. FIG. 5 is a schematic diagram showing another example of an ink cartridge.

(ink)
The ink of the present invention is an ink used in an inkjet recording apparatus having a filter in the ink flow path, and contains water, a coloring material, a silicone surfactant, and silicone compound particles, and the volume average of the silicone compound particles is The particle diameter (D ₅₀ ) is 1.01 μm to 5.00 μm, and the content of the silicone compound particles is 0.01% by mass to 0.20% by mass.

Conventionally, when an ink storage container having an air introduction channel for introducing air and having a structure for generating air bubbles in the ink is used, the air bubbles flow out from the ink tank together with the ink and are carried to the ink ejection head. , there is a problem that the ink discharge head causes filling and discharge failures. In addition, in an inkjet recording apparatus having an ink container that allows contact between air and ink, such as an open-type ink cartridge, when ink is supplied to the ink ejection head, ink containing air bubbles may flow into the ink ejection head. There is a problem that the ink is transported and causes filling and ejection failures in the ink ejection head. Such defective filling and discharging in the ink discharging head causes deterioration of initial filling properties and continuous printing stability.
In response to the above problem, the present inventors have made intensive studies, and have found that even if the ink having the above configuration does not contain a fluorine-based surfactant, the ink has excellent defoaming properties and can be discharged when filled with ink. It has been found that the ink is excellent in properties, ejection stability, and ink permeability.

The ink contains water, a coloring material, a silicone surfactant, and silicone compound particles, and if necessary, organic solvents, resin particles, surfactants other than the silicone surfactant, and various additives. Contains other ingredients.

<Silicone surfactant>
The silicone surfactant is not particularly limited and can be appropriately selected depending on the intended purpose. terminal-modified polydimethylsiloxane; These may be used individually by 1 type, and may use 2 or more types together. Among these, polyether-modified silicone surfactants having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as a modifying group are particularly preferred as the silicone surfactant, since they exhibit excellent properties as water-based surfactants. preferable.

As such a silicone surfactant, an appropriately synthesized one may be used, or a commercially available product may be used. Commercially available silicone surfactants are available from, for example, BYK Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Dow Corning Toray Silicone Co., Ltd., Nihon Emulsion Co., Ltd., Kyoeisha Chemical Co., Ltd., and the like.

（但し、前記一般式（Ｓ－１）において、ｍ、ｐ、ａ、及びｂは、それぞれ独立に、整数を表し、Ｒは、アルキレン基を表し、Ｒ’は、アルキル基を表す。） The polyether-modified silicone surfactant is not particularly limited and can be appropriately selected depending on the intended purpose. and those introduced into the Si portion side chain of.

(However, in the general formula (S-1), m, p, a, and b each independently represent an integer, R represents an alkylene group, and R' represents an alkyl group.)

As the polyether-modified silicone surfactant, commercially available products can be used. -1906EX (above, manufactured by Nippon Emulsion Co., Ltd.), DOWSIL FZ-2105, FZ-2118, FZ-2154, FZ-2161, FZ-2162, FZ-2163, FZ-2164 (above, Toray Dow Corning Silicone Co., Ltd. company), BYK-33, BYK-387 (manufactured by BYK-Chemie Corporation), TSF4440, TSF4452, TSF4453 (manufactured by Toshiba Silicon Co., Ltd.), and the like.

（但し、前記一般式（１）において、ｍは０～７の整数を表し、ｎは２～１５の整数を表す。） Among these, as the silicone surfactant, a surfactant represented by the following general formula (1) is particularly preferable from the viewpoint of improving ink permeability and ink defoaming properties.

(However, in the general formula (1), m represents an integer of 0 to 7, and n represents an integer of 2 to 15.)

The content of the silicone surfactant in the ink is not particularly limited and can be appropriately selected according to the purpose.

The silicone surfactant in the ink is subjected to various analyzes such as mass spectrometry, ultraviolet spectroscopy, infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, carbon-13 nuclear magnetic resonance spectroscopy, and elemental analysis. can be confirmed by the method.

<Silicone compound particles>
The silicone compound particles are not particularly limited as long as they are silicone compound particles having a volume average particle diameter (D ₅₀ ) of 1.01 μm to 5.00 μm, and can be appropriately selected according to the purpose. Siloxane particles can be used.

The volume average particle diameter (D ₅₀ ) of the silicone compound particles is 1.01 μm to 5.00 μm, preferably 1.10 μm to 4.50 μm. When the volume average particle diameter (D ₅₀ ) of the silicone compound particles is less than 1.01 μm, the initial filling property is poor and the ink foams. gets worse. On the other hand, when the volume average particle diameter (D ₅₀ ) of the silicone compound particles is 1.01 μm to 5.00 μm, it is advantageous in terms of improving initial filling properties, ejection stability, liquid permeability, and defoaming properties. be.

The silicone compound particles may be blended in the ink as they are, or may be blended as a silicone emulsion in which the silicone compound particles are dispersed in a liquid.

The silicone emulsion can be prepared by emulsifying approximately two particles of the silicone compound per molecule using an anionic surfactant and water, and optionally adding colloidal silica and an organotin compound.
The pH of the silicone emulsion is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 9 to 11.5.

The content of the silicone compound particles in the ink is 0.01% by mass to 0.20% by mass with respect to the total amount of the ink. When the content of the silicone compound particles is 0.01% by mass to 0.20% by mass, it is advantageous in that ejection stability and liquid permeability are improved.

The silicone compound particles in the ink are analyzed by various analysis methods such as mass spectrometry, ultraviolet spectroscopy, infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, carbon-13 nuclear magnetic resonance spectroscopy, and elemental analysis. can be confirmed by

<colorant>
The coloring material is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include pigments and dyes.

The pigment is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include inorganic pigments and organic pigments. These may be used individually by 1 type, and may use 2 or more types together. Mixed crystals may also be used.

Examples of the pigments include black pigments, yellow pigments, magenta pigments, cyan pigments, white pigments, green pigments, orange pigments, glossy color pigments such as gold and silver, and metallic pigments.

Examples of the inorganic pigments include titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, and chrome yellow. In addition to these inorganic pigments, carbon black produced by known methods such as the contact method, the furnace method and the thermal method can also be used.

Examples of the organic pigment include azo pigments, polycyclic pigments (e.g., phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, etc.). ), dye chelates (eg, basic dye chelates, acid dye chelates, etc.), nitro pigments, nitroso pigments, aniline black, and the like.

Among these pigments, those having good affinity with the solvent are preferably used as the pigment. In addition, resin hollow particles and inorganic hollow particles can also be used.

Specific examples of the pigments for black include carbon blacks (C.I. Pigment Black 7) such as furnace black, lamp black, acetylene black, and channel black; copper and iron (C.I. Pigment Black 11); , metals such as titanium oxide; and organic pigments such as aniline black (C.I. Pigment Black 1).

Further, specific examples of the pigments for color include C.I. I. Pigment yellow 1, 3, 12, 13, 14, 17, 24, 34, 35, 37, 42 (yellow iron oxide), 53, 55, 74, 81, 83, 95, 97, 98, 100, 101, 104 , 108, 109, 110, 117, 120, 138, 150, 153, 155, 180, 185, 213; I. Pigment Orange 5, 13, 16, 17, 36, 43, 51; C.I. I. Pigment Red 1, 2, 3, 5, 17, 22, 23, 31, 38, 48:2 (Permanent Red 2B (Ca)), 48:3, 48:4, 49:1, 52:2, 53: 1, 57:1 (brilliant carmine 6B), 60:1, 63:1, 63:2, 64:1, 81, 83, 88, 101 (red red), 104, 105, 106, 108 (cadmium red), 112, 114, 122 (quinacridone magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 184, 185, 190, 193, 202, 207, 208, 209, 213, 219, 224, 254, 264; I. Pigment Violet 1 (rhodamine lake), 3, 5:1, 16, 19, 23, 38; C.I. I. Pigment Blue 1, 2, 15 (phthalocyanine blue), 15:1, 15:2, 15:3, 15:4 (phthalocyanine blue), 16, 17:1, 56, 60, 63; C.I. I. Pigment Green 1, 4, 7, 8, 10, 17, 18, 36 and the like.

The dye is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include acid dyes, direct dyes, reactive dyes, basic dyes and the like. These may be used individually by 1 type, and may use 2 or more types together.

Specific examples of the dye include C.I. I. Acid Yellow 17, 23, 42, 44, 79, 142; C.I. I. Acid Red 52, 80, 82, 249, 254, 289; C.I. I. Acid Blue 9, 45, 249; C.I. I. Acid Black 1, 2, 24, 94; C.I. I. Food Black 1, 2; C.I. I. Direct Yellow 1, 12, 24, 33, 50, 55, 58, 86, 132, 142, 144, 173; C.I. I. Direct Red 1, 4, 9, 80, 81, 225, 227; C.I. I. Direct Blue 1, 2, 15, 71, 86, 87, 98, 165, 199, 202; C.I. I. Direct Black 19, 38, 51, 71, 154, 168, 171, 195; C.I. I. Reactive Red 14, 32, 55, 79, 249; C.I. I. Reactive Black 3, 4, 35 and the like.

The content of the coloring material is not particularly limited and can be appropriately selected according to the purpose. is more preferable, and 4% by mass to 10% by mass is even more preferable.

In order to obtain the ink by dispersing the pigment, there are a method of introducing a hydrophilic functional group into the pigment to make it a self-dispersing pigment, a method of coating the surface of the pigment with a resin to disperse it, and a dispersing agent. For example, a method of using and dispersing.

As a method of introducing a hydrophilic functional group into the pigment to make it a self-dispersing pigment, for example, by adding a functional group such as a sulfone group or a carboxyl group to the pigment (for example, carbon), it is dispersed in water. methods that make it possible.

Examples of the method of coating the surface of the pigment with a resin to disperse the pigment include a method of encapsulating the pigment in microcapsules to make it dispersible in water. This can be rephrased as a resin-coated pigment. In this case, it is not necessary for all the pigments contained in the ink to be coated with a resin. May be distributed.

Examples of the method of dispersing using the dispersant include a method of dispersing using a known low-molecular-weight dispersant and high-molecular-weight dispersant typified by surfactants.
The dispersant is not particularly limited and can be appropriately selected according to the type of the pigment. Examples include anionic surfactants, cationic surfactants, amphoteric surfactants, and nonionic surfactants. etc. These may be used individually by 1 type, and may use 2 or more types together. Also, RT-100 (nonionic surfactant, manufactured by Takemoto Oil & Fat Co., Ltd.) and sodium naphthalenesulfonate formalin condensate can be suitably used as a dispersant.

The volume average particle diameter (D ₅₀ ) of the pigment is not particularly limited and can be appropriately selected depending on the intended purpose. .
The volume average particle diameter of the pigment in the present invention is measured using a particle size distribution analyzer (Nanotrac UPA-EX150, manufactured by Nikkiso Co., Ltd.), and the solid content concentration of the pigment in the measurement sample is 0.01% by mass. 50% volume average particle diameter ( _D50 ) measured at 23° C. using a sample diluted with water, with a particle refractive index of 1.51, a particle density of 1.4 g/cm ³ , and pure water parameters as solvent parameters. be.
When pigment-containing polymer particles are used as the colorant, the volume average particle diameter (D ₅₀ ) of the pigment-containing polymer particles including the polymer portion may be measured.

<<ratio [volume average particle size of coloring material ( _D50 )/volume average particle size of silicone compound particles ( _D50 )]>>
The ratio of the volume average particle diameter (D ₅₀ ) of the coloring material to the volume average particle diameter (D ₅₀ ) of the silicone compound particles [volume average particle diameter (D ₅₀ ) of the coloring material/volume average particle diameter of the silicone compound particles (D ₅₀ )] is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.02 to 0.1, more preferably 0.05 to 0.1. When the ratio [volume average particle diameter (D ₅₀ ) of the coloring material/volume average particle diameter (D ₅₀ ) of the silicone compound particles] is within the range of 0.02 to 0.1, the liquid permeability of the ink is improved. It is advantageous in terms of improvement.

<Water>
The water is not particularly limited and can be appropriately selected depending on the purpose. be done. These may be used individually by 1 type, and may use 2 or more types together.

The content of the water is not particularly limited and can be appropriately selected according to the purpose. % or less, more preferably 20% by mass to 60% by mass.

<Other ingredients>
The ink may further contain other components such as an organic solvent, resin particles, surfactants other than the silicone surfactant, and various additives, if necessary.

<<Organic solvent>>
The organic solvent is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include water-soluble organic solvents, polyol compounds having 8 or more carbon atoms, glycol ether compounds, and the like. These may be used individually by 1 type, and may use 2 or more types together.

Examples of the water-soluble organic solvent include polyhydric alcohols, ethers such as polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, sulfur-containing compounds, and the like. is mentioned. These may be used individually by 1 type, and may use 2 or more types together.

Specific examples of the water-soluble organic solvent include ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol and 1,4-butanediol. , 2,3-butanediol, 3-methyl-1,3-butanediol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 2,4-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,3-hexanediol, 2,5-hexanediol, 1,5-hexanediol, glycerin , 1,2,6-hexanetriol, 2-ethyl-1,3-hexanediol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl-1 , 3-pentanediol, petriol and other polyhydric alcohols; ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monoethyl ether polyhydric alcohol alkyl ethers such as; ethylene glycol monophenyl ether, polyhydric alcohol aryl ethers such as ethylene glycol monobenzyl ether; 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, Nitrogen-containing heterocyclic compounds such as 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, γ-butyrolactone; formamide, N-methylformamide, N,N-dimethylformamide, 3-methoxy-N,N-dimethyl Amides such as propionamide and 3-butoxy-N,N-dimethylpropionamide; Amines such as monoethanolamine, diethanolamine and triethylamine; Sulfur-containing compounds such as dimethylsulfoxide, sulfolane and thiodiethanol; Propylene carbonate, ethylene carbonate and the like is mentioned.

It is preferable to use an organic solvent having a boiling point of 250° C. or less because the water-soluble organic solvent not only functions as a wetting agent but also provides good drying properties.

Specific examples of the polyol compound having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol and 2,2,4-trimethyl-1,3-pentanediol.

Specific examples of the glycol ether compound include polyhydric alcohols such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether. Alkyl ethers; polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether;

The polyol compound having 8 or more carbon atoms and the glycol ether compound can improve ink permeability when paper is used as a recording medium.

The content of the organic solvent is not particularly limited and can be appropriately selected according to the purpose, but from the viewpoint of excellent ejection stability, it is preferably 30% by mass to 50% by mass with respect to the total amount of the ink. .

<Resin particles>
The ink preferably contains resin particles mainly for the purpose of improving the abrasion resistance of the image and improving the storage stability when a pigment is used as the coloring material.
The resin particles are not particularly limited and can be appropriately selected according to the intended purpose. are preferred, and resin particles of polyurethane resins, acrylic resins, and styrene-acrylic resins are preferred for improving storage stability. However, since there are few resin particles capable of simultaneously improving the abrasion resistance of an image and improving the storage stability, two types of resin particles may be used in combination. These resin particles are commercially available in the form of a resin emulsion in which resin particles are dispersed in water, and are readily available. Therefore, as the resin emulsion, commercially available ones can be appropriately selected and used as necessary.
Next, urethane resin emulsions and acrylic resin emulsions are illustrated as representative resin emulsions.

(1) Urethane Resin Emulsion The urethane resin of the urethane resin emulsion is obtained by polymerizing polyisocyanate with polyether polyol, polyester polyol, polylactone polyol, polycarbonate polyol, or the like.

Examples of the polyisocyanate include aliphatic diisocyanate compounds such as hexamethylene diisocyanate and 2,2,4-trimethylhexamethylene diisocyanate; isophorone diisocyanate, hydrogenated xylylene diisocyanate, 1,4-cyclohexane diisocyanate, 4,4'- Alicyclic diisocyanate compounds such as dicyclohexylmethane diisocyanate; araliphatic diisocyanate compounds such as xylylene diisocyanate and tetramethylxylene diisocyanate; aromatic diisocyanate compounds such as toluylene diisocyanate and phenylmethane diisocyanate; modified products of these diisocyanates (carbodiimide, uretdione, uretimine-containing modified products, etc.).

Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, polyhexamethylene ether glycol and the like.

Examples of the polyester polyols include polyethylene adipate, polybutylene adipate, polyneopentyl adipate, poly-3-methylpentyl adipate, polyethylene/butylene adipate, and polyneopentyl/hexyl adipate.

Examples of the polylactone polyol include polycaprolactone diol and polyomega-hydroxycaproic acid polyol.

Examples of the polycarbonate polyols include diols (eg, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, etc.), phosgene, and diaryl They include those known in the art, such as products obtained from reactions with carbonates (eg, diphenyl carbonate, etc.) or cyclic carbonates (eg, ethylene carbonate, propylene carbonate, etc.).

(2) Acrylic resin emulsion The acrylic resin of the acrylic resin emulsion is obtained by polymerizing an acrylic monomer alone or by copolymerizing it with another monomer.

Examples of the acrylic monomers include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, and acrylic acid. -n-pentyl, isopentyl acrylate, neopentyl acrylate, 3-(methyl)butyl acrylate, 2-ethylhexyl acrylate, hexyl acrylate, cyclohexyl acrylate, octyl acrylate, nonyl acrylate, decyl acrylate, undecyl acrylate, dodecyl acrylate, phenyl acrylate, methyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, n-methacrylate Pentyl, isopentyl methacrylate, neopentyl methacrylate, 3-(methyl)butyl methacrylate, 2-ethylhexyl methacrylate, hexyl methacrylate, octyl methacrylate, nonyl methacrylate, decyl methacrylate, undecyl methacrylate, dodecyl methacrylate , acrylic acid, methacrylic acid, acrylamide, methacrylamide, acrylonitrile, methacrylonitrile, and the like.

Examples of the other monomers include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-tert-butyl vinyl aromatic hydrocarbons such as styrene, p-chlorostyrene, and divinylbenzene; unsaturated carboxylic acids such as itaconic acid and maleic acid; N-substituted maleimides, maleic anhydride, vinyl ketones, vinyl acetate, and vinylidene chloride; .

These resin emulsions exhibit even better water dispersibility by introducing an ionic group into the resin. Such ionic groups include, for example, a sulfonic acid group, a carboxylic acid group, a sulfuric acid group, a phosphoric acid group, a phosphonic acid group and a phosphinic acid group, or alkali metal bases, alkaline earth metal bases, ammonium bases thereof, Examples include primary to tertiary amine groups. Among these, alkali metal carboxylate bases, ammonium carboxylate bases, alkali metal sulfonate bases, and ammonium sulfonate bases are preferred, and alkali metal sulfonate bases and ammonium sulfonate bases are particularly preferred in terms of water dispersion stability. .
The introduction of the ionic group into the resin is carried out by adding a monomer having an ionic group during synthesis of the resin. Preferred salts are Li, K, or Na salts.

The volume average particle diameter (D ₅₀ ) of the resin particles is not particularly limited and can be appropriately selected depending on the intended purpose. The following is preferable, 10 nm or more and 200 nm or less is more preferable, and 10 nm or more and 100 nm or less is particularly preferable.
The volume average particle diameter (D ₅₀ ) of the resin particles can be measured, for example, using a particle size distribution analyzer (Nanotrac UPA-EX150, manufactured by Nikkiso Co., Ltd.).

The content of the resin particles is not particularly limited and can be appropriately selected according to the purpose. % or less is more preferable.

<<Surfactant other than silicone surfactant>>
The ink contains the silicone surfactant, but may additionally contain a surfactant other than the silicone surfactant.
Surfactants other than the silicone surfactant are not particularly limited, and can be appropriately selected depending on the type of coloring agent and the combination of organic solvents. , those with high leveling properties are preferred. These may be used individually by 1 type, and may use 2 or more types together. Among these, as surfactants other than the silicone surfactant, at least one selected from anionic surfactants having an acetylene structure and nonionic surfactants having an acetylene structure, and surfactants not having an acetylene structure More preferably, it is used in combination with at least one selected from surfactants to which hydrocarbon-based ethylene oxide (EO) chains are added.

The content of the surfactant other than the silicone surfactant is not particularly limited, and can be appropriately selected depending on the purpose. %, more preferably 0.1% by mass to 1% by mass.

<<Additives>>
The ink may contain additives such as an antifoaming agent, an antiseptic antifungal agent, an anticorrosive agent, and a pH adjuster, as long as the effects of the present invention are not impaired.

- Defoamer -
The antifoaming agent is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include polyether antifoaming agents and fatty acid ester antifoaming agents. These may be used individually by 1 type, and may use 2 or more types together.

- Antiseptic and antifungal agent -
The antiseptic/antifungal agent is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include 1,2-benzisothiazolin-3-one.

-anti-rust-
The rust inhibitor is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include acidic sulfites and sodium thiosulfate.

-pH adjuster-
The pH adjuster is not particularly limited and can be appropriately selected depending on the intended purpose, but is preferably one capable of adjusting the pH to 7 or higher, such as amines such as diethanolamine and triethanolamine. is mentioned.

The content of the additive is not particularly limited as long as the effects of the present invention are not impaired, and can be appropriately selected according to the purpose.

The physical properties of the ink are not particularly limited and can be appropriately selected according to the purpose. For example, viscosity, surface tension, pH, etc. are preferably within the following ranges.

The viscosity of the ink at 25° C. is not particularly limited and can be appropriately selected depending on the intended purpose. By setting the ink viscosity to 5 mPa·s or more, the effect of improving print density and character quality is obtained. On the other hand, by suppressing the ink viscosity to 15 mPa·s or less, ejection stability can be ensured.
Here, the viscosity of the ink can be measured at 25° C. using, for example, a viscometer (RE-550L, manufactured by Toki Sangyo Co., Ltd.).

The surface tension of the ink is not particularly limited and can be appropriately selected depending on the intended purpose. When the surface tension is 35 mN/m or less, the leveling of the ink on the recording medium is improved.

The pH of the ink is not particularly limited and can be appropriately selected according to the purpose.

The coloring of the ink is not particularly limited and can be appropriately selected according to the coloring material. Examples thereof include yellow, magenta, cyan, and black. A multicolor image can be formed by using an ink set containing two or more of these colors, and a full-color image can be formed by using an ink set containing all the colors. be able to.

<Ink manufacturing method>
The method for producing the ink is not particularly limited, _and can be appropriately selected from known ink production methods. is 1.01 μm to 5.00 μm silicone compound particles, and if necessary, other components such as organic solvents, resin particles, surfactants other than the silicone surfactant, various additives, etc., in an aqueous medium. Examples include a method of dispersing or dissolving and, if necessary, stirring and mixing.
The dispersion can be performed by, for example, a sand mill, homogenizer, ball mill, paint shaker, ultrasonic disperser, etc., and the stirring and mixing can be performed by a stirrer equipped with ordinary stirring blades, a magnetic stirrer, a high-speed disperser, etc. It can be done by

The ink can be suitably used in an inkjet recording device (printer, etc.) having a filter in the ink flow path. It can also be used in a printer or the like having a function of promoting print fixation. Therefore, the ink can be particularly suitably used in the inkjet recording apparatus, inkjet recording method, ink cartridge, and ink recorded matter of the present invention, which will be described in detail below.

(Inkjet recording apparatus and inkjet recording method)
The ink jet recording apparatus of the present invention comprises the ink of the present invention and a filter having an average pore size of 4 μm to 22 μm in the ink flow path, and further optionally ink flying means, stimulus generating means, and control means. , and other means such as treatment liquid applying means.
Further, the ink jet recording method of the present invention includes an ink flying step of applying a stimulus to the ink of the present invention and causing the ink to fly onto a recording medium to form an image. It includes other processes such as a control process and a treatment liquid application process.
The inkjet recording method of the present invention can be suitably practiced by the inkjet recording apparatus of the present invention. The inkjet recording method of the present invention will be described below together with the description of the inkjet recording apparatus of the present invention.

<Filter>
The ink jet recording apparatus includes at least one filter in the ink flow path. The average pore diameter of the filter is 4 μm to 22 μm, preferably 5 μm to 20 μm from the viewpoint of ejection stability and liquid permeability.
The thickness of the filter is not particularly limited, and can be appropriately selected from known ink manufacturing methods, but is preferably 0.1 mm to 0.5 mm.

The filter is not particularly limited as long as it is provided in the ink flow path, and may be provided in the ink supply path, but is preferably provided between the ink cartridge and the ink ejection head. The ink is excellent in antifoaming properties, and is advantageous in that the antifoaming properties are further improved by passing the ink through the filter and being supplied to the ink ejection head.

The material of the filter is not particularly limited and can be appropriately selected according to the purpose. However, since the filter is always in contact with the ink, it is preferably made of stainless steel or polyimide from the viewpoint of corrosion resistance. preferable. Among these, austenitic stainless steel, and more preferably SUS304, SUS316, and SUS316L are preferable as the material for the filter because of their excellent corrosion resistance. The filter may be made of only one kind of material among these, or may be made of two or more kinds of materials. Among these, the filter preferably contains at least one selected from SUS304, SUS316, and SUS316L, and more preferably comprises one selected from SUS304, SUS316, and SUS316L.

The shape of the filter is not particularly limited as long as the filter has an average pore size of 4 μm to 22 μm, and can be appropriately selected from known filters. Among these, a filter made of stainless steel or polyimide plate with a large number of uniform holes made by punching or laser, a sintered filter made by layering stainless steel fibers in felt and sintering them, or a twilled fabric made of stainless steel fibers. The use of the twilled twill filter formed by the above method is desirable because it provides an ink jet recording apparatus and an ink supply unit with longer-term ejection stability.

<Ink ejection head>
The ink discharge head of the ink jet recording apparatus is not particularly limited, and can be appropriately selected from known ones. A so-called piezo type in which ink droplets are ejected by changing the internal volume of the ink channel by deforming the vibration plate forming the wall surface of the channel (see Japanese Patent Application Laid-Open No. 2-51734). A so-called thermal type in which ink is heated to generate air bubbles (see Japanese Patent Laid-Open No. 59911/1986). An electrostatic type in which ink droplets are ejected by changing the internal volume of the ink flow path by deforming the vibration plate due to the electrostatic force generated between it and the electrode (see Japanese Patent Application Laid-Open No. 6-71882). be done. The ink can be used satisfactorily in an inkjet recording apparatus equipped with any ink discharge head.

<Recording medium>
The recording medium used in the inkjet recording apparatus is not particularly limited and can be appropriately selected according to the purpose. Examples include plain paper, glossy paper, special paper, cloth, film, OHP sheet, and general-purpose printing paper. is mentioned. These may be used individually by 1 type, and may use 2 or more types together. Among these, coated paper based on photographic printing paper, which has a coating layer and is excellent in glossiness, is preferably used.
When plain paper having no coating layer is used, plain paper having a sizing degree of 10S or more and an air permeability of 5S to 50S, which is generally used as copy paper, is preferable.

<Ink Flying Process and Ink Flying Means>
The ink flying step is a step of applying a stimulus (energy) to the ink to fly the ink to form an image on a recording medium.
The ink flying means is a means for applying a stimulus (energy) to the ink and causing the ink to fly to form an image on a recording medium.
The ink flying step is preferably performed by the ink flying means.

The ink flying means is not particularly limited, and examples thereof include various nozzles for ejecting ink.

The nozzle diameter of the nozzle is not particularly limited and can be appropriately selected depending on the intended purpose.

In the ink jet recording apparatus, at least part of the liquid chamber portion, the fluid resistance portion, the vibration plate, and the nozzle member of the ink discharge head is preferably made of a material containing at least one of silicon and nickel.

The manner in which the ink flies is not particularly limited, and varies depending on the type of the stimulus. a thermal energy corresponding to a recording signal is applied to the ink, the thermal energy generates bubbles in the ink, and the pressure of the bubbles causes the ink to be ejected as droplets from the nozzle holes of the ink ejection head. mentioned. Further, when the stimulus is "pressure", for example, by applying a voltage to a piezoelectric element adhered to a position called a pressure chamber in the ink flow path in the ink ejection head, the piezoelectric element bends and the pressure chamber volume is reduced, and the ink is ejected as droplets from the nozzle holes of the ink ejection head.

The size of the ink droplets to be ejected, the speed of ejection, the driving frequency, the resolution, etc. are not particularly limited and can be appropriately selected according to the purpose. is preferably 3×10 ⁻¹⁵ m ³ to 40×10 ⁻¹⁵ m ³ (3 pL to 40 pL), and the jet speed is preferably 5 m/s to 20 m/s. , the driving frequency is preferably 1 kHz or higher, and the resolution is preferably 300 dpi or higher.

<Stimulus Generating Step and Stimulus Generating Means>
The stimulus generation step is a step of generating a stimulus (energy) to be applied to the ink in the ink flying step.
The stimulus generating means is means for generating a stimulus (energy) to be applied to the ink by the ink flying means.
The stimulus generating step is preferably performed by the stimulus generating means.

The stimulus (energy) is not particularly limited and can be appropriately selected according to the purpose. Examples thereof include heat (temperature), pressure, vibration, and light. These may be used individually by 1 type, and may use 2 or more types together. Among these, heat and pressure are preferable as the stimulus.

The stimulus generating means is not particularly limited and can be appropriately selected according to the purpose. . Specific examples of the stimulus generating means include a piezoelectric actuator such as a piezoelectric element, a thermal actuator utilizing a phase change due to film boiling of a liquid using an electrothermal conversion element such as a heating resistor, and a metal phase change due to a temperature change. A shape memory alloy actuator, an electrostatic actuator using an electrostatic force, and the like are included.

<Control process and control means>
The control step is a step of controlling each step in the inkjet recording method.
The control means is means for controlling each means in the inkjet recording apparatus.
The control step is preferably performed by the control means.

The control means is not particularly limited as long as it can control the movement of each means, and can be appropriately selected according to the purpose. Examples thereof include devices such as sequencers and computers.

<Treatment Liquid Application Step and Treatment Liquid Application Means>
The treatment liquid applying step is a step of applying the treatment liquid to the recording medium either before or after applying the ink to the recording medium, or both.
The treatment liquid applying means is means for applying the treatment liquid to the recording medium either before or after applying the ink to the recording medium, or both.
The treatment liquid application step is preferably performed by the treatment liquid application means.
The treatment liquid application step and the treatment liquid application means can improve image quality such as image density, strike-through, and bleeding on a recording medium.

The treatment liquid applied to the recording medium before the ink is applied to the recording medium (hereinafter sometimes referred to as "pretreatment liquid") is not particularly limited and can be appropriately selected according to the purpose. , for example, those containing a flocculant, an organic solvent, and water, and further containing a surfactant, an antifoaming agent, a pH adjuster, an antiseptic antifungal agent, an antirust agent, and the like, if necessary. These may be used individually by 1 type, and may use 2 or more types together.
The organic solvent, the surfactant, the antifoaming agent, the pH adjuster, the antiseptic antifungal agent, and the anticorrosive agent can be the same materials as those used for the ink, and other known treatments can be used. Materials used for liquids can also be used.
The type of the flocculant is not particularly limited, and examples thereof include water-soluble cationic polymers, acids, polyvalent metal salts and the like.

The treatment liquid (hereinafter sometimes referred to as "post-treatment liquid") to be applied to the recording medium after the ink has been applied to the recording medium is not particularly limited as long as it can form a transparent layer. However, it can be appropriately selected depending on the purpose, and examples thereof include organic solvents, water, resins, surfactants, antifoaming agents, pH adjusters, antiseptic antifungal agents, antirust agents, and the like. These may be used individually by 1 type, and may use 2 or more types together.
The organic solvent, the water, the resin, the surfactant, the antifoaming agent, the pH adjuster, the antiseptic antifungal agent, and the antirust agent can be the same materials as those used for the ink. In addition, materials used in known processing liquids can also be used.

Here, one mode of carrying out the inkjet recording method of the present invention using a serial inkjet recording apparatus will be described with reference to the drawings.
The inkjet printing apparatus shown in FIG. 1 includes an apparatus main body 101, a paper feed tray 102 on the front surface 112 of the apparatus main body 101 for loading paper into the apparatus main body 101, and an image formed (printed) by loading paper into the apparatus main body 101. The apparatus has a discharge tray 103 for stocking printed sheets, an ink cartridge loading section 104, and an upper cover 111 on the upper surface of the main body 101 of the apparatus. An operation unit 105 including operation keys and a display is arranged on the top surface of the ink cartridge loading unit 104 . The ink cartridge loading section 104 has an openable front cover 115 for attaching and detaching the ink cartridge 201 .

As shown in FIGS. 2 and 3, a carriage 133 is slidable in the main scanning direction by guide rods 131 and stays 132, which are guide members that extend across left and right side plates (not shown). It is held movably, and moved and scanned in the direction of the arrow in FIG. 3 by a main scanning motor (not shown).
A carriage 133 is provided with a plurality of recording heads 134 each having four ink discharge heads for discharging recording ink droplets of yellow (Y), cyan (C), magenta (M), and black (Bk). The outlets are arranged in a direction crossing the main scanning direction, and the ink droplet ejection direction is directed downward.
The inkjet recording head constituting the recording head 134 includes a piezoelectric actuator such as a piezoelectric element, a thermal actuator utilizing a phase change due to film boiling of a liquid using an electrothermal conversion element such as a heating resistor, and a metal phase change due to a temperature change. A shape memory alloy actuator using change, an electrostatic actuator using electrostatic force, or the like provided as energy generating means for ejecting ink can be used.

Further, the carriage 133 is equipped with sub-tanks 135 of respective colors for supplying inks of respective colors to the recording head 134 . The sub-tank 135 is replenished with the recording ink of the present invention supplied from the ink cartridge 201 of the present invention loaded in the ink cartridge loading section 104 via a recording ink supply tube (not shown).
On the other hand, as a paper feed unit for feeding the paper 142 stacked on the paper stacking unit (pressure plate) 141 of the paper feed tray 102, a half-moon roller (feeder) separates and feeds the paper 142 from the paper stacking unit 141 one by one. A separation pad 144 made of a material having a large friction coefficient is provided facing the paper roller 143) and the paper feed roller 143, and the separation pad 144 is biased toward the paper feed roller 143 side.
As a transport unit for transporting the paper 142 fed from the paper feed unit below the recording head 134, a transport belt 151 for electrostatically attracting the paper 142 and transporting it, and a guide 145 from the paper feed unit. A counter roller 152 for sandwiching and conveying the paper 142 sent through the conveyor belt 151 and the paper 142 sent substantially vertically upward is turned about 90° and made to follow the conveyor belt 151. and a leading end pressure roller 155 urged toward the transport belt 151 by a pressing member 154 . Further, a charging roller 156, which is charging means for charging the surface of the conveying belt 151, is provided.
The transport belt 151 is an endless belt, stretched between a transport roller 157 and a tension roller 158, and rotatable in the belt transport direction. The conveying belt 151 includes, for example, a surface layer that serves as a paper adsorption surface and is formed of a resin material, for example, a copolymer of tetrafluoroethylene and ethylene (ETFE) with a thickness of about 40 μm that is not subjected to resistance control. It has a back layer (medium resistance layer, ground layer) whose resistance is controlled by carbon as a material. A guide member 161 is arranged on the back side of the transport belt 151 so as to correspond to the printing area of the recording head 134 . As a paper discharge unit for discharging the paper 142 recorded by the recording head 134, a separation claw 171 for separating the paper 142 from the conveying belt 151, a paper discharge roller 172, and a paper discharge roller 173 are provided. A paper discharge tray 103 is arranged below the paper discharge rollers 172 .

A double-sided paper feeding unit 181 is detachably attached to the rear portion of the apparatus main body 101 . The double-sided paper feeding unit 181 takes in the paper 142 returned by the reverse rotation of the conveying belt 151 , reverses it, and feeds it again between the counter roller 152 and the conveying belt 151 . A manual paper feeding unit 182 is provided on the upper surface of the double-sided paper feeding unit 181 .
In this inkjet recording apparatus, the paper 142 is separated and fed one by one from the paper feeding unit, and the paper 142 fed substantially vertically upward is guided by the guide 145 and is placed between the conveying belt 151 and the counter roller 152 . transported sandwiched between Further, the leading edge is guided by the conveying guide 153 and pressed against the conveying belt 151 by the leading edge pressing roller 155, so that the conveying direction is changed by approximately 90°.
At this time, the conveying belt 151 is charged by the charging roller 156, and the paper 142 is electrostatically attracted to the conveying belt 151 and conveyed. Therefore, by driving the recording head 134 according to the image signal while moving the carriage 133, ink droplets are ejected onto the stationary paper 142 to record one line. Record next line. Upon receiving a recording end signal or a signal indicating that the trailing edge of the paper 142 has reached the recording area, the recording operation is terminated and the paper 142 is discharged to the paper discharge tray 103 .
Then, when the remaining amount of ink in the sub-tank 135 is near the end, the sub-tank 135 is replenished with the required amount of ink from the ink cartridge 201 .

In this inkjet recording apparatus, when the recording ink in the ink cartridge 201 of the present invention is used up, the housing of the ink cartridge 201 can be disassembled and only the ink bag 241 inside can be replaced. In addition, the ink cartridge 201 can be stably supplied with the recording ink even when the ink cartridge 201 is installed vertically and configured to be loaded from the front. Therefore, even when the apparatus main body 101 is installed with its upper side blocked, for example, when it is stored in a rack, or when an object is placed on the upper surface of the apparatus main body 101, the ink cartridge 201 cannot be replaced. can be easily done.

Although an example of application to a serial type (shuttle type) ink jet recording apparatus in which a carriage scans has been described here, the present invention can be similarly applied to a line type ink jet recording apparatus having a line type head.

The inkjet recording apparatus and inkjet recording method of the present invention can be applied to various types of recording by the inkjet recording method, and are particularly suitable for, for example, inkjet recording printers, facsimile machines, copiers, printer/fax/copier complex machines, and the like. can be applied.

(ink cartridge)
The ink cartridge of the present invention contains the ink of the present invention in a container, and further includes other members appropriately selected as necessary.

The container is not particularly limited, and its shape, structure, size, material, etc. can be appropriately selected according to the purpose. and the like are preferably mentioned.

Next, the ink cartridge will be specifically described with reference to FIGS. 4 and 5, but the present invention is not limited to this.
FIG. 4 is a schematic diagram showing an ink cartridge 201, and FIG. 5 is a schematic diagram showing a modification of the ink cartridge of FIG. As shown in FIG. 4, the ink is filled into the ink bag 241 from the ink inlet 242, and after the ink bag 241 is exhausted, the ink inlet 242 is closed by fusion. During use, the needle of the ink jet recording apparatus main body 101 shown in FIG. The ink bag 241 is formed of a packaging member such as an impermeable aluminum laminate film. As shown in FIG. 5, the ink bag 241 is normally accommodated in a cartridge case 244 made of plastic, and is detachably attached to various ink jet recording apparatuses for use. It is particularly preferable that the ink cartridge 201 of the present invention contains the ink of the present invention and is detachably attached to various inkjet recording apparatuses.

(ink record)
A recorded matter recorded by the ink jet recording apparatus of the present invention and the ink jet recording method of the present invention using the ink of the present invention is the ink recorded matter of the present invention.
The ink recorded matter has an image formed on a recording medium using the ink of the present invention.

Examples of the recording medium include those described in the item (inkjet recording apparatus and inkjet recording method).

The ink recorded matter has high image quality, does not bleed, and is excellent in stability over time.

Preparation Examples, Production Examples, Comparative Production Examples, Examples, and Comparative Examples are given below to specifically describe the present invention, but the present invention is in no way limited to these Preparation Examples, Production Examples, and Examples. not a thing In Preparation Examples, Production Examples, Comparative Production Examples, Examples, and Comparative Examples, "parts" and "%" indicate "mass parts" and "mass%" unless otherwise specified.

(Preparation Example 1)
<Preparation of Magenta Pigment-Containing Polymer Fine Particle Dispersion>
-Preparation of polymer solution A-
After sufficiently replacing the inside of a 1 L flask equipped with a mechanical stirrer, thermometer, nitrogen gas inlet tube, reflux tube, and dropping funnel with nitrogen gas, 11.2 g of styrene, 2.8 g of acrylic acid, and 12.0 g of lauryl methacrylate were added. , 4.0 g of polyethylene glycol methacrylate, 4.0 g of styrene macromer, and 0.4 g of mercaptoethanol were mixed and heated to 65°C.
Next, styrene 100.8 g, acrylic acid 25.2 g, lauryl methacrylate 108.0 g, polyethylene glycol methacrylate 36.0 g, hydroxylethyl methacrylate 60.0 g, styrene macromer 36.0 g, mercaptoethanol 3.6 g, azobismethyl valero. 2.4 g of nitrile and 18 g of methyl ethyl ketone were mixed to prepare a mixed solution, which was dropped into the flask over 2.5 hours.
After dropping, 0.8 g of azobismethylvaleronitrile and 18 g of methyl ethyl ketone were mixed to prepare a mixed solution, which was dropped into the flask over 0.5 hour.
Next, after aging at 65° C. for 1 hour, 0.8 g of azobismethylvaleronitrile was added and further aged for 1 hour. After completion of the reaction, 364 g of methyl ethyl ketone was added to the flask to obtain 800 g of polymer solution A having a concentration of 50%.

-Preparation of Magenta Pigment-Containing Polymer Fine Particle Dispersion-
28 g of the polymer solution A, C.I. I. Pigment Red 122 (42 g), 1 mol/L potassium hydroxide aqueous solution (13.6 g), methyl ethyl ketone (20 g), and deionized water (13.6 g) were mixed, thoroughly stirred, and kneaded using a roll mill. The obtained paste was poured into 200 g of pure water and stirred sufficiently, and methyl ethyl ketone and water were distilled off using an evaporator. Pressure filtration was performed using a ride membrane filter to obtain a magenta pigment-containing polymer fine particle dispersion having a pigment content of 15% and a solid content concentration of 20%.

-Measurement of volume average particle size ( _D50 )-
The resulting magenta pigment-containing polymer fine particle dispersion was diluted with pure water so that the solid content concentration of the polymer fine particles was 0.01%, and a particle size distribution analyzer (Nanotrac UPA-EX150, manufactured by Nikkiso Co., Ltd.) was used. The pigment volume average particle diameter (D ₅₀ ) was measured using At this time, the measurement was performed under the measurement conditions of 23° C. using a particle refractive index of 1.51, a particle density of 1.4 g/cm ³ , and pure water parameters as solvent parameters.
As a result, the volume average particle diameter (D ₅₀ ) of the polymer fine particles in the magenta pigment-containing polymer fine particle dispersion was 82.7 nm.

(Preparation Example 2)
<Preparation of Cyan Pigment-Containing Polymer Fine Particle Dispersion>
In the preparation of the magenta pigment-containing polymer fine particle dispersion of Preparation Example 1, C.I. I. Pigment Red 122, C.I. I. A cyan pigment-containing polymer fine particle dispersion having a pigment content of 15% and a solid concentration of 20% was obtained in the same manner as in Preparation Example 1, except that Pigment Blue was changed to 15:3.
The volume average particle diameter (D ₅₀ ) of the polymer fine particles in the obtained cyan pigment-containing polymer fine particle dispersion was measured in the same manner as in Preparation Example 1. As a result, the volume average particle diameter (D ₅₀ ) of the polymer fine particles in the cyan pigment-containing polymer fine particle dispersion was 120.0 nm.

(Preparation Example 3)
<Preparation of silicone emulsion 1>
381.2 g of polydimethylsiloxane fluid (having hydroxyl groups at the ends, degree of polymerization 35), polymethylhydrogensiloxane (having trimethylsiloxy groups at the ends, viscosity at 25°C of 0.13 Pa s, content of silicon-bonded hydrogen atoms was 1.6%), 15.9 g of 30% sodium lauryl sulfate aqueous solution, and 186 g of distilled water were prepared. This mixture was homogenized twice using a single-stage laboratory homogenizer to prepare a uniform emulsion with a volume average particle size (D ₅₀ ) of 1.1 μm. After adding 3.2 g of dodecylbenzenesulfonic acid to this emulsion, the mixture was allowed to stand at 25° C. for 24 hours for polymerization. Polymerization was terminated by adding a sufficient amount of diethylamine to raise the pH to 7-7.5. As a result, silicone emulsion 1 (polydimethylsiloxane emulsion, volume average particle size (D ₅₀ ): 1.1 μm) was obtained.
The volume average particle diameter (D ₅₀ ) of the silicone emulsion was measured using a particle size distribution analyzer (Nanotrac UPA-EX150, manufactured by Nikkiso Co., Ltd.).

(Preparation Example 4)
Silicone emulsion 2 (polydimethylsiloxane emulsion, volume average particle size (D ₅₀ ) 4.5 μm) was obtained in the same manner as in Preparation Example 3, except that the shear force of the homogenizer was changed.

(Preparation Example 5)
Silicone emulsion 3 (polydimethylsiloxane emulsion, volume average particle size ( _D50 ): 195 nm) was obtained in the same manner as in Preparation Example 3, except that the shear force of the homogenizer was changed.

(Preparation Example 6)
Silicone emulsion 4 (polydimethylsiloxane emulsion, volume average particle size (D ₅₀ ) 6.0 μm) was obtained in the same manner as in Preparation Example 3, except that the shear force of the homogenizer was changed.

(Production Examples 1 to 7 and Comparative Production Examples 1 to 5)
<Production of inkjet ink>
Each inkjet ink was prepared by the following procedure.
Pigment dispersion, resin dispersion, organic solvent, surfactant, and water (pure) are mixed with the composition and content shown in Tables 1-1 and 1-2 below, and stirred for 1 hour to mix uniformly. bottom. This dispersion is filtered under pressure through a polyvinylidene fluoride membrane filter with an average pore size of 5.0 μm to remove coarse particles and dust, and the inkjet inks of Production Examples 1 to 7 and Comparative Production Examples 1 to 5 are obtained. made.
In Tables 1-1 and 1-2 below, the contents of pigment dispersions and resin dispersions are shown in terms of solid content. In addition, the ratio [volume average particle size (D ₅₀ ) of coloring material/volume average particle size (D ₅₀ ) of silicone emulsion] is rounded to the second decimal place.

-Measurement of ink viscosity-
The viscosity of each inkjet ink of Production Examples 1 to 7 and Comparative Production Examples 1 to 5 was measured at 25° C. using a viscometer (RE-550L, manufactured by Toki Sangyo Co., Ltd.). The results are shown in Tables 1-1 and 1-2 below.

（但し、前記一般式（１）において、ｍは０～７の整数を表し、ｎは２～１５の整数を表す。）
※上記表１―１及び表１－２の「フッ素界面活性剤１」として、製品名：フタージェント ２５０（株式会社ネオス製）を使用した。 * Product name: Ucoat UA-3945 (solid content concentration 38.4%, volume average particle diameter (D ₅₀ ) 35 nm, manufactured by Sanyo Chemical Industries, Ltd. as "polyurethane emulsion" in Tables 1-1 and 1-2 above )It was used.
* Product name: KF-6043 (PEG-10 dimethicone, silicone linear polyether-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) is used as "silicone surfactant 1" in Tables 1-1 and 1-2 above. used.
* In Tables 1-1 and 1-2 above, "silicone surfactant 2" is a compound represented by the following general formula (1), product name: TEGO (registered trademark) Wet 270 (manufactured by Evonik Industries). It was used.

(However, in the general formula (1), m represents an integer of 0 to 7, and n represents an integer of 2 to 15.)
* Product name: Futergent 250 (manufactured by Neos Co., Ltd.) was used as "fluorosurfactant 1" in Tables 1-1 and 1-2 above.

(Examples 1 to 11 and Comparative Examples 1 to 5)
Each of the inkjet inks of Production Examples 1 to 7 and Comparative Production Examples 1 to 5 and an inkjet recording apparatus having a filter shown in Table 2 below in the ink channel were used in the combination shown in Table 2 below, and evaluated by the following evaluation method. "Initial fillability", "foam in cap", "ejection stability", and "liquid permeability" were evaluated. The results are shown in Table 2 below.
The inkjet recording apparatus used in the following evaluation has a filter in the ink flow path. The material of the filter is metal fiber, and the average pore size and thickness of the filter are shown in Table 2 below. The filter was provided between the ink cartridge and the ink discharge head.

<Initial fillability>
The following evaluations were made under environmental conditions adjusted to 23±0.5° C. and 50±5% RH.
An inkjet recording apparatus (IPSiO GXe-5500, manufactured by Ricoh Co., Ltd.) was filled with a 10% propylene glycol aqueous solution, and then each of the inkjet inks of Production Examples 1 to 7 and Comparative Production Examples 1 to 5 was filled. Using this, when the nozzle check pattern was printed, the number of nozzle cleaning operations until the number of non-ejecting nozzles became 0 was measured. "Initial filling property" was evaluated.
-Evaluation Criteria for Initial Fillability-
A: The number of non-ejection nozzles becomes 0 after performing nozzle cleaning 1 to 2 times. B: The number of non-ejection nozzles becomes 0 after performing nozzle cleaning 3 to 10 times.

<Foam inside the cap>
The following evaluations were made under environmental conditions adjusted to 23±0.5° C. and 50±5% RH.
An inkjet recording apparatus (IPSiO GXe-5500, manufactured by Ricoh Co., Ltd.) was filled with each of the inkjet inks of Production Examples 1 to 7 and Comparative Production Examples 1 to 5. Using this, ink refresh (an operation of discarding the ink accumulated in the ink discharge head and sucking up ink from the cartridge) was performed five times. The "foam in cap" of Examples 1-11 and Comparative Examples 1-5 was evaluated.
-Evaluation Criteria for Initial Fillability-
A: No bubbles inside the cap B: Bubbles only at the bottom of the cap C: Bubbles all over the cap

<Ejection stability>
The following evaluations were made under environmental conditions adjusted to 32±0.5° C. and 50±5% RH.
An inkjet recording apparatus (IPSiO GXe-5500, manufactured by Ricoh Co., Ltd.) was filled with the inkjet inks of Production Examples 1 to 7 and Comparative Production Examples 1 to 5, and left for 6 hours with the cap opened. After the nozzle cleaning was carried out once after the standing, a nozzle check pattern was printed to confirm the presence or absence of non-ejecting nozzles. Further, when there was a nozzle that failed to eject ink, nozzle cleaning was performed twice to confirm the presence or absence of a nozzle that failed to eject ink. If there was a nozzle that failed to eject ink even after performing nozzle cleaning three times in total, ink was refreshed once more, and the presence or absence of a nozzle that failed to eject ink was checked. Through the above operation, the "discharge stability" of Examples 1 to 11 and Comparative Examples 1 to 5 was evaluated based on the following evaluation criteria.
-Evaluation Criteria for Ejection Stability-
A: After performing nozzle cleaning once, no nozzle failed to eject. B: After performing nozzle cleaning once, there was a nozzle that failed to eject. There is a non-ejection nozzle, and the non-ejection is recovered by nozzle cleaning 3 times and nozzle refresh 1 time.

<Liquid Permeability>
The following evaluations were made under environmental conditions adjusted to 23±0.5° C. and 50±5% RH.
An inkjet recording device (IPSiO GXe-5500, manufactured by Ricoh Co., Ltd.) is filled with ink, and 5 kg of each of the inkjet inks of Production Examples 1 to 7 and Comparative Production Examples 1 to 5 is passed through, and then a nozzle check pattern is printed. Then, the presence or absence of non-ejecting nozzles was checked. Further, when there was a nozzle that failed to eject, nozzle cleaning was performed three more times to confirm the presence or absence of a nozzle that failed to eject. From the above operation, the "liquid permeability" of Examples 1 to 11 and Comparative Examples 1 to 5 was evaluated based on the following evaluation criteria.
-Evaluation Criteria for Liquid Permeability-
A: After performing nozzle cleaning once, no nozzle failed to eject. B: After performing nozzle cleaning once, there was a nozzle that failed to eject, and ejection failure was recovered within three times of nozzle cleaning. C: Ink ejection disabled.

（但し、前記一般式（１）において、ｍは０～７の整数を表し、ｎは２～１５の整数を表す。）
＜３＞ 前記色材の体積平均粒子径（Ｄ_５０）と前記シリコーン化合物粒子の体積平均粒子径（Ｄ_５０）との比［色材の体積平均粒子径（Ｄ_５０）／シリコーン化合物粒子の体積平均粒子径（Ｄ_５０）］が、０．０２～０．１の範囲にある前記＜１＞から＜２＞のいずれかに記載のインクである。
＜４＞ 前記＜１＞から＜３＞のいずれかに記載のインクと、
前記インクの流路に平均細孔径４μｍ～２２μｍのフィルターと、
を有することを特徴とするインクジェット記録装置である。
＜５＞ 前記＜１＞から＜３＞のいずれかに記載のインクに刺激を印加し、記録媒体に、前記インクを飛翔させて画像を形成するインク飛翔工程を含むことを特徴とするインクジェット記録方法である。
＜６＞ 前記＜１＞から＜３＞のいずれかに記載のインクを容器内に収容してなることを特徴とするインクカートリッジである。
＜７＞ 記録媒体上に、前記＜１＞から＜３＞のいずれかに記載のインクにより記録された画像を有してなることを特徴とするインク記録物である。 Embodiments of the present invention include, for example, the following.
<1> An ink used in an inkjet recording apparatus having a filter in the ink flow path,
Containing water, a coloring material, a silicone surfactant, and silicone compound particles,
The volume average particle diameter (D ₅₀ ) of the silicone compound particles is 1.01 μm to 5.00 μm, and the content of the silicone compound particles is 0.01% by mass to 0.20% by mass. Ink.
<2> The ink according to <1>, wherein the silicone surfactant contains a surfactant represented by the following general formula (1).

(However, in the general formula (1), m represents an integer of 0 to 7, and n represents an integer of 2 to 15.)
<3> Ratio of the volume average particle diameter (D ₅₀ ) of the coloring material to the volume average particle diameter (D ₅₀ ) of the silicone compound particles [volume average particle diameter (D ₅₀ ) of the coloring material/volume of the silicone compound particles The ink according to any one of <1> and <2> above, wherein the average particle diameter (D ₅₀ )] is in the range of 0.02 to 0.1.
<4> the ink according to any one of <1> to <3>;
a filter with an average pore size of 4 μm to 22 μm in the ink flow path;
An inkjet recording apparatus characterized by having
<5> Ink jet recording comprising an ink jetting step of applying a stimulus to the ink according to any one of <1> to <3> to jet the ink onto a recording medium to form an image. The method.
<6> An ink cartridge containing the ink according to any one of <1> to <3> in a container.
<7> An ink recorded matter comprising an image recorded with the ink according to any one of <1> to <3> on a recording medium.

The ink according to any one of <1> to <3>, the inkjet recording apparatus according to <4>, the inkjet recording method according to <5>, the ink cartridge according to <6>, and the < 7> can solve the conventional problems and achieve the object of the present invention.

Since the ink of the present invention is excellent in dischargeability, defoaming property, discharge stability, and ink permeability at the time of ink filling, when printing on a recording medium, especially when printing on coated paper, It has excellent fixability and storage stability, and can be suitably used for inkjet recording apparatuses, inkjet recording methods, ink cartridges, and ink recorded matter.
Moreover, the inkjet recording apparatus and inkjet recording method of the present invention can be applied to various types of recording by an inkjet recording method, for example, inkjet recording printers, facsimile machines, copiers, printer/facsimile/copier complex machines, and the like. It can be suitably applied.

101 Apparatus Main Body 102 Paper Feed Tray 103 Paper Ejection Tray 104 Ink Cartridge Loading Section 105 Operation Section 111 Upper Cover 112 Front 115 Front Cover 131 Guide Rod 132 Stay 133 Carriage 134 Recording Head 135 Sub Tank 141 Paper Stacking Section 142 Paper 143 Paper Feed Roller 144 Separation Pad 145 Guide 151 Conveying Belt 152 Counter Roller 153 Conveying Guide 154 Pressing Member 155 Tip Pressing Roller 156 Charging Roller 157 Conveying Roller 158 Tension Roller 161 Guide Member 171 Separation Claw 172 Discharge Roller 173 Discharge Roller 181 Duplex Paper Feed Unit 182 Manual feed unit 201 Ink cartridge 241 Ink bag 242 Ink inlet 243 Ink outlet 244 Cartridge case

Japanese Patent Application Laid-Open No. 2013-223980

Claims (4)

An ink used in an inkjet recording apparatus having a filter in the ink flow path,
Containing water, a coloring material, a silicone surfactant, and silicone compound particles,
The volume average particle diameter (D ₅₀ ) of the silicone compound particles is 1.01 μm to 5.00 μm, and the content of the silicone compound particles is 0.01% by mass to 0.20% by mass. ink. 2. The ink according to claim 1, wherein the silicone surfactant contains a surfactant represented by the following general formula (1).

(However, in the general formula (1), m represents an integer of 0 to 7, and n represents an integer of 2 to 15.) The ratio of the volume average particle diameter (D ₅₀ ) of the coloring material to the volume average particle diameter (D ₅₀ ) of the silicone compound particles [volume average particle diameter (D ₅₀ ) of the coloring material/volume average particle diameter of the silicone compound particles (D ₅₀ )] is in the range of 0.02 to 0.1. the ink according to any one of claims 1 to 3;
a filter with an average pore size of 4 μm to 22 μm in the ink flow path;
An inkjet recording apparatus comprising:

Images