JP2012201717A - Inkjet recording ink, inkjet recording method, ink cartridge and inkjet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide inkjet recording ink which is high in image density, is excellent in discharging stability, and is produced at a low cost; to provide an inkjet recording method using the same; to provide an ink cartridge; and to provide an inkjet recorder.SOLUTION: (1) The inkjet recording ink is characterized by comprising at least a colorant A, a colorant B, a surfactant, a water-soluble organic solvent and water, wherein one of the colorant A and the colorant B is a pigment, and the other is a dye; the triboelectric property of the colorant A to a resin coat carrier is negative, and the triboelectric property of the colorant B to the resin coat carrier is positive. (2) The inkjet recording ink described in (1), is such that the colorant A is a copper phthalocyanine-based pigment, and the colorant B is an anthraquinone-based dye.

Description

  The present invention relates to an ink for ink jet recording, an ink jet recording method using the same, an ink cartridge, and an ink jet recording apparatus.

The choice and dispersion of colorants is very important in aqueous inks. Colorants are roughly classified into dyes and pigments. Each has advantages and disadvantages, and is properly used according to the image quality target and cost.
However, inks using conventional dyes have vivid colors and are inexpensive, but there are problems with image quality such as lack of tinting strength, bleeding and bleeding, and poor light resistance, resulting in long-term image storage. There was a problem that the color of the.
On the other hand, an ink using a pigment is excellent in coloring power and light resistance because the colorant is fast, but it is necessary to finely disperse the pigment. Nozzle clogging and filter clogging occur, and an abnormal image such as image smearing or fading due to defective ejection occurs. In addition, the manufacturing process of the pigment dispersion is complicated, the cost of the pigment itself is high, and the ink is expensive.
With respect to these problems, Patent Document 1 discloses a dye in which a specific functional group is coordinated on the surface of the dye for the purpose of improving the light resistance of the cyan dye. However, since it is necessary to cause a special reaction on the surface of the dye, processing takes time and cost, and image quality, light resistance, ejection stability, and cost cannot all be satisfied.
Patent Document 2 discloses a pigment having a dispersed particle size defined for the purpose of improving the color tone of a cyan pigment. However, the particle size of the pigment is sufficient for color reproduction, but is too large to obtain ejection stability, and all of image quality, light resistance, ejection stability, and cost cannot be satisfied.

In addition, when a conventional general copper phthalocyanine pigment is used as a colorant, a cyan ink having coloring power and excellent light resistance can be obtained, but the color reproducibility is insufficient and ejection caused by pigment particles is performed. There is a problem with stability. In addition, re-aggregation of particles, sticking to the nozzle surface and the head, and the like occur over time, and an abnormal image such as blurring or omission occurs. Furthermore, there is a phenomenon in which pigment particles accumulate on a filter for removing foreign matters such as dust in the head over time, and this phenomenon is noticeable in copper phthalocyanine pigments.
On the other hand, when a cyan dye is used, it does not have a particle size distribution like a pigment, so that the filter is not physically clogged. However, although there is vividness of color development due to the dye, the coloring power and light resistance are insufficient, and the fixation (dyeing) to the nozzle and head is more severe than the pigment.

  An object of the present invention is to provide a low-cost ink for ink jet recording having a high image density and excellent ejection stability, an ink jet recording method using the ink, an ink cartridge, and an ink jet recording apparatus.

The above problems are solved by the following inventions 1) to 5).
1) At least colorant A, colorant B, surfactant, water-soluble organic solvent and water, one of colorant A and colorant B is a pigment and the other is a dye, and colorant A and a resin-coated carrier Ink jet recording ink, characterized in that the triboelectric chargeability between the colorant B and the resin-coated carrier is positive.
2) The ink for ink jet recording according to 1), wherein the colorant A is a copper phthalocyanine pigment, and the colorant B is an anthraquinone dye.
3) An ink jet recording method comprising at least an application step of applying a stimulus to the ink for ink jet recording described in 1) or 2) and an ink flying step of flying the ink to form an image.
4) An ink cartridge in which the ink for ink jet recording described in 1) or 2) is contained in a container.
5) In an inkjet recording apparatus having at least an application means for applying a stimulus to the inkjet recording ink and an ink flying means for flying the inkjet recording ink from the inkjet head to form an image, the nozzle plate surface of the inkjet head is a silicone resin Alternatively, an ink jet recording apparatus comprising an ink repellent layer containing nickel and mounting the ink cartridge described in 4).

  According to the present invention, it is possible to provide a low-cost inkjet recording ink having a high image density and excellent ejection stability, an inkjet recording method, an ink cartridge, and an inkjet recording apparatus using the ink. This is particularly effective for cyan ink.

1 is a diagram illustrating an example of an ink jet recording apparatus of the present invention.

Hereinafter, the present invention will be described in detail. Ink jet recording ink is abbreviated as ink as appropriate.
<Colorant>
Copper phthalocyanine pigments have a complex structure coordinated around copper metal, are easily charged negatively, and accumulate negative charges through friction, charge injection, and the like. For this reason, when ink passes through the filter, it is presumed that negative charges are gradually generated due to friction with the filter, and pigment particles charged up accumulate on the filter.
As a result of the study, the present inventors have found that the various phenomena when using the copper phthalocyanine pigment described above are caused not only by the particle size of the pigment particles but also by the electrostatic properties of the pigment. I found out.
Then, as a means of canceling the negative charge of the copper phthalocyanine pigment and simultaneously solving the respective problems of the pigment and the dye, the copper phthalocyanine pigment having a negative triboelectric chargeability with the resin coat carrier, and the resin coat carrier It was found that the above-mentioned problems can be solved by using a dye having a positive triboelectric chargeability.
In this way, by combining a pigment and a dye having opposite tribocharging properties, the negative charge accumulation of the pigment is canceled by the positive charge accumulation of the dye and becomes electrically neutralized. Filter clogging is eliminated. In addition, the color tone and vividness of the dye are added to the coloring power of the pigment, while the fading property of the dye is concealed by the pigment. Simple combinations of pigments and dyes are known, but focusing on the charge can solve the problem due to the charge, while at the same time solving other problems.
Further, as can be seen from the problem-solving principle of the present invention, the same effect can be obtained even if the positive and negative frictional charging properties of the pigment and the dye are switched.
The colorant having a negative triboelectric chargeability with the resin-coated carrier is preferably “Colorant A” and the positive colorant is “Colorant B”, and the mixing ratio of the two is preferably 8: 2 to 2: 8. If it is this range, the ability to neutralize electrostatically will be exhibited sufficiently.

<Colorant A>
Examples of the colorant A exhibiting negative chargeability include copper phthalocyanine pigments.
The copper phthalocyanine pigment is a polycyclic aromatic compound having an isoindole structure in which four phthalimides are bridged by nitrogen atoms around a copper atom, and the aromatic ring can be substituted with a halogen atom or the like. Has one hydrogen atom. The structure in which hydrogen atoms remain is called an unsubstituted copper phthalocyanine pigment, but is classified into α-type copper phthalocyanine pigment, β-type copper phthalocyanine pigment, ε-type copper phthalocyanine pigment, etc. according to its crystal form.
The copper phthalocyanine pigment that can be used in the present invention is not particularly limited. I. Pigment blue 15: 1, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 15: 4, C.I. I. Pigment blue 15: 6. Above all, from the viewpoint of coloring power, saturation and cost, C.I. I. Pigment blue 15: 3, and C.I. I. Pigment Blue 15: 4 is desirable.
Further, metal-containing azo dyes (monoazo dye 1: 2 type metal complex compounds) obtained by coupling reaction of naphthol derivatives and aminophenol derivatives have nitro groups or halogen atoms as functional groups, and are particularly shown in the following [Chemical Formula 1]. Those having a chromium atom at the center exhibit extremely stable negative chargeability.

<Colorant B>
An example of the colorant B exhibiting positive chargeability is an anthraquinone dye.
There are no particular restrictions on the anthraquinone dyes that can be used in the present invention. I. Acid Blue 25, C.I. I. Acid Blue 49, C.I. I. Acid Blue 129, C.I. I. Solvent Blue 35, C.I. I. Solvent Blue 68, C.I. I. Solvent Blue 132, C.I. I. Solvent Blue 111 etc. are mentioned. Above all, from the point of saturation and polarity, C.I. I. Solvent Blue 35, and C.I. I. Solvent Blue 111 is desirable.
In addition, the nigrosine dye (CI Solvent Black 5) shown in the following [Chemical Formula 2] is a heat-condensed nitrobenzene, aniline, and aniline hydrochloride, and has an amino group in the skeleton, which is an extremely stable plus. Shows chargeability.

In addition, xanthene dyes (CI Solvent Red 49) exhibit bright magenta and strong positive chargeability.
Also, the molybdate chelate pigment (CI Pigment Red 81), which is a dye lake pigment, exhibits a red color and exhibits a strong positive chargeability.
In addition, organic pigments having an azo group as shown in the following [Chemical Formula 3] often exhibit positive chargeability.

<Measurement of frictional charging>
The triboelectric chargeability of the pigment may be measured by a triboelectric charge amount measuring method generally used for dry toners. As the carrier, a metal core material such as ferrite, magnetite, iron powder or the like having an average particle size of 30 to 100 μm is coated with a silicone resin or the like.
As the pigment, it is preferable to use a pigment that has been sized through a mesh having a mesh size of 250 μm in advance. The sized pigment and the resin-coated carrier are mixed, for example, at a weight ratio of 5:95, and stirred for 10 minutes at 250 rpm under a magnetic force of 1500 G by a mag roll mill. Thereafter, the charge amount is measured using a blow-off device, and the polarity (plus charge property or minus charge property) is determined.

<Aqueous dispersion>
In the ink of the present invention, an aqueous dispersion other than the water-soluble dye is used. Since dyes and pigments have different structures and different triboelectric properties, they cannot be mixed and dispersed. Further, since the pigment is insoluble in water, it must be used as a dispersion. The dispersion method may be a known method. For example, the colorant may be added to an aqueous solution in which the dispersant is dissolved and mixed with stirring.
As the pigment dispersant, either a nonionic surfactant having an HLB value of 10 to 20 or an anionic surfactant is preferable.
Examples of the nonionic surfactant having an HLB value of 10 to 20 include polyoxyethylene alkyl ether, polyoxyalkylene alkyl ether, polyoxyethylene polycyclic phenyl ether, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene Examples include ethylene alkyl phenyl ether, polyoxyethylene alkyl amine, polyoxyethylene alkyl amide, and acetylene glycol. Among these, polyoxyethylene lauryl ether, polyoxyethylene-β-naphthyl ether, polyoxyethylene sorbitan monooleate, and polyoxyethylene styrene phenyl ether are particularly preferable.

Examples of the anionic surfactant having an HLB value of 10 to 20 include polyoxyethylene alkyl ether acetate, polyoxyethylene aryl ether sulfonate NH ₄ salt, alkyl benzene sulfonate (for example, NH ₄ salt, Na salt, Ca Salt), alkyl diphenyl ether disulfonate (eg NH ₄ salt, Na salt, Ca salt, etc.), dialkyl succinate sulfonate Na salt, dialkyl sulfosuccinate Na salt, naphthalene sulfonate formalin condensate Na salt, polyoxyethylene poly Examples thereof include cyclic phenyl ether sulfate ester salts (for example, NH ₄ salt and Na salt), laurates, polyoxyethylene alkyl ether sulfates, oleates and the like. In particular, dioctyl sulfosuccinic acid Na salt and polyoxyethylene styrene phenyl ether sulfonic acid NH ₄ salt are particularly preferred.

<Preparation of ink>
The ink of the present invention can be prepared by a known method. For example, it can be produced by stirring and mixing a colorant dispersion, a surfactant, a water-soluble organic solvent, water, and the like, filtering coarse particles with a filter, a centrifugal separator or the like, and deaeration as necessary.

<Surfactant>
As the surfactant, at least one selected from an anionic surfactant, a nonionic surfactant, a silicone surfactant, a fluorine surfactant, and the like is used. Of these, silicone surfactants and fluorine surfactants are particularly preferred. These surfactants may be used alone or in combination of two or more.
Examples of the silicone surfactant include side chain modified polydimethylsiloxane, both terminal modified polydimethylsiloxane, one terminal modified polydimethylsiloxane, and side chain both terminal modified polydimethylsiloxane.
Examples of the fluorine-based surfactant include a perfluoroalkyl sulfonic acid compound, a perfluoroalkyl carboxylic acid compound, a perfluoroalkyl phosphate compound, a perfluoroalkyl ethylene oxide adduct, and a perfluoroalkyl ether group in the side chain. Examples include polyoxyalkylene ether polymer compounds.
The content of the surfactant in the ink is preferably 0.01 to 3.0% by mass, and more preferably 0.5 to 2.0% by mass. When the content is less than 0.01% by mass, the effect of adding a surfactant may be lost. When the content exceeds 3.0% by mass, the permeability to a recording medium becomes higher than necessary, and the image density is increased. May be reduced or show through.

<Water-soluble organic solvent>
Examples of the water-soluble organic solvent include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,3-butanediol, 3-methyl-1,3-butanediol, and 1,5-pentanediol. 1,6-hexanediol, 2-ethyl-1,3-hexanediol, glycerin, 1,2,3-butanetriol, 1,2,4-butanetriol, 1,2,6-hexanetriol, Polyhydric alcohols such as petriol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl Polyether alcohol alkyl ethers such as ether ether, propylene glycol monoethyl ether, polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, 2-pyrrolidone, N-methyl-2-pyrrolidone, N Nitrogen-containing heterocyclic compounds such as -hydroxyethyl-2-pyrrolidone, 1,3-dimethylimidazolidinone, ε-caprolactam, γ-butyrolactone, amides such as formamide, N-methylformamide, N, N-dimethylformamide, Amines such as monoethanolamine, diethanolamine, triethanolamine, monoethylamine, diethylamine and triethylamine, sulfur-containing compounds such as dimethyl sulfoxide, sulfolane and thiodiethanol, propylene Emissions carbonate, and the like ethylene carbonate, but not limited thereto.
These water-soluble organic solvents may also serve as a wetting agent.
The content of the water-soluble organic solvent is 50% by weight or less, preferably 5 to 40% by weight, more preferably 10 to 35% by weight based on the total amount of the ink.

<Other ingredients>
In the ink of the present invention, as necessary, a penetrant, a resin emulsion, a pH adjuster, an antiseptic / antifungal agent, a chelating reagent, a rust inhibitor, an antioxidant, an ultraviolet absorber, an antifoaming agent, An oxygen absorber, a light stabilizer and the like can be added.

Examples of the penetrant include 2-ethyl-2-methyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, and 2-methyl-2-propyl-1,3-propanediol. 3,3-dimethyl-1,2-butanediol, 2,2,4-trimethyl-1,3-pentanediol, 2,4-dimethyl-2,4-pentanediol, 2-ethyl-1,3- Aliphatic diols such as hexanediol, 2,5-dimethyl-2,5-hexanediol, 5-hexene-1,2-diol, diethylene glycol monophenyl ether, ethylene glycol monophenyl ether, ethylene glycol monoallyl ether, diethylene glycol mono Butyl ether, propylene glycol monobutyl ether, tetraethylene glycol Alkyl and aryl ethers of polyhydric alcohols such as chlorophenyl ether, such as lower alcohols such as ethanol and the like.
Among these, 2,2,4-trimethyl-1,3-pentanediol and 2-ethyl-1,3-hexanediol are preferable.
The content of the penetrant in the ink is preferably 0.1 to 4.0% by weight. If the content is 0.1% by weight or more, quick-drying can be obtained, and the image does not bleed. If the content is 4.0% by weight or less, the dispersion stability of the coloring material is not impaired, and the nozzle eye There will be no clogging, and the penetrability into the recording medium will be unnecessarily high, so that there will be no reduction in image density and no show-through.

The resin emulsion is preferably at least one selected from polyurethane, styrene acrylic, and acrylic silicon. In particular, for a water-based pigment dispersion, a polyurethane-based resin emulsion is more preferable in terms of fixing property to paper.
The resin emulsion exists as an O / W type emulsion when used as a raw material for ink preparation or after ink preparation. Emulsions of polyurethane resins are made by emulsifying a relatively hydrophilic ordinary polyurethane resin using an emulsifier, and self-introducing functional groups that function as an emulsifier into the resin itself by means such as copolymerization. There is an emulsion of an emulsifying resin. Either of them can be used, but care must be taken because there is a slight difference in the dispersion stability of the pigment and emulsion particles depending on the combination of the components of the ink.
In various combinations with pigments and dispersants, an anionic self-emulsifying polyurethane emulsion is always excellent in dispersion stability. In this case, the polyurethane resin is preferably a polycarbonate type rather than a polyester type, and more preferably an ether type than a polyester type or a polycarbonate type, in terms of pigment fixation and dispersion stability. The reason is not clear, but the non-ether type is often weak in solvent resistance, and the viscosity tends to aggregate when the ink is stored at high temperature. Although the reason is not clear, the processing time can be shortened by adding the resin emulsion to the water-based pigment dispersion and water-based pigment ink, followed by heat treatment.

The pH adjuster is not particularly limited as long as the pH can be adjusted to 7 to 11 without adversely affecting the ink jet ink to be prepared, and can be appropriately selected according to the purpose. Examples include alcohol amines, alkali metal hydroxides, ammonium hydroxides, phosphonium hydroxides, alkali metal carbonates, and the like.
When the pH is less than 7 or more than 11, the amount of the ink jet head or the ink supply unit that melts is large, and problems such as ink deterioration, leakage, and ejection failure may occur.
Examples of the alcohol amines include diethanolamine, triethanolamine, 2-amino-2-ethyl-1,3-propanediol, and the like.
Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, and potassium hydroxide.
Examples of the ammonium hydroxide include ammonium hydroxide and quaternary ammonium hydroxide.
Examples of the phosphonium hydroxide include quaternary phosphonium hydroxide.
Examples of the alkali metal carbonate include lithium carbonate, sodium carbonate, and potassium carbonate.

Examples of the antiseptic / antifungal agent include sodium dehydroacetate, sodium sorbate, 2-pyridinethiol-1-oxide sodium, sodium benzoate, sodium pentachlorophenol, and the like.
Examples of the chelating reagent include sodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate, sodium uramil diacetate, and the like.
Examples of the rust inhibitor include acidic sulfite, sodium thiosulfate, ammonium thiodiglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, and dicyclohexylammonium nitrite.
Examples of the antioxidant include phenolic antioxidants (including hindered phenolic antioxidants), amine-based antioxidants, sulfur-based antioxidants, phosphorus-based antioxidants, and the like.

Examples of the ultraviolet absorber include a benzophenone ultraviolet absorber, a benzotriazole ultraviolet absorber, a salicylate ultraviolet absorber, a cyanoacrylate ultraviolet absorber, and a nickel complex ultraviolet absorber.
Examples of the antifoaming agent include polyol-based antifoaming agents and silicone-based antifoaming agents. The polyol-based antifoaming agent contains an alkylene oxide group in its structure, and those having a large amount of ethylene oxide group are particularly excellent in dispersion stability in water and excellent in the antifoaming effect in the liquid. Many silicone-based antifoaming agents have an excellent foam breaking effect, and there are oil types, compound types, self-emulsifying types, emulsion types, etc., but considering use in aqueous systems, self-emulsifying types or emulsions It is desirable to use a mold in order to ensure reliability. In addition, modified silicone-based antifoaming agents such as amino-modified, carbinol-modified, methacryl-modified, polyether-modified, alkyl-modified, higher fatty acid ester-modified, alkylene oxide-modified, etc. may be used.

<Ink cartridge>
The ink cartridge of the present invention is one in which the ink for ink jet recording of the present invention is contained in a container. There are no particular restrictions on the container, and its shape, structure, size, material, etc. can be appropriately selected according to the purpose. For example, a container having an ink bag formed of an aluminum laminate film, a resin film, etc., plastic A case etc. are mentioned suitably.

<Inkjet recording apparatus>
The ink jet recording apparatus of the present invention has discharge means for forming an image by discharging the ink for ink jet recording of the present invention, and further has other means as necessary.
Examples of the printing (discharge) method include a continuous jet type and an on-demand type. Further, examples of the on-demand type include a piezo method, a thermal method, and an electrostatic method.
Here, the ink cartridge and the ink jet recording apparatus of the present invention will be described with reference to FIG.
In FIG. 1, an ink cartridge 20 that accommodates an ink jet recording ink of the present invention is accommodated in a carriage 18. Here, a plurality of ink cartridges 20 are provided for convenience, but it is not necessary to have a plurality. In such a state, the ink for ink jet recording is supplied from the ink cartridge 20 to the droplet discharge head 18 a mounted on the carriage 18. In FIG. 1, the discharge nozzle surface is in an invisible state because it faces downward, but ink jet recording ink is discharged from this discharge nozzle.
The droplet discharge head 18 a mounted on the carriage 18 is guided and moved by the guide shafts 21 and 22 by the timing belt 23 driven by the main scanning motor 26.
On the other hand, a specific coated paper (image support) is placed at a position facing the droplet discharge head 18 a by the platen 19. In FIG. 1, 1 is an ink jet recording apparatus, 2 is a main body housing,
Reference numeral 16 denotes a gear mechanism, 17 denotes a sub-scanning motor, 24 denotes a main scanning motor, and 25 and 27 denote gear mechanisms.
The ink repellent layer containing silicone resin or nickel on the nozzle plate surface of the ink jet head can be appropriately provided by diverting a known technique.

When an image is formed on an image support using the ink jet recording apparatus containing the ink for ink jet recording or ink cartridge of the present invention, an image forming body printed on the image support on demand is obtained. Further, the replenishment of ink for ink jet recording can be replaced in units of ink cartridges.
There is no restriction | limiting in particular as said image support body, According to the objective, it can select suitably, For example, a plain paper, glossy paper, special paper, cloth, a film, an OHP sheet etc. are mentioned. Among these, paper is particularly preferable.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Preparation of colorant>
The colorant shown in Table 1 below was sized with a sieve having a mesh size of 250 mesh.
Next, the carrier is a resin-coated carrier obtained by spray-coating a silicone resin on a ferrite core material having an average particle size of 50 μm, and the sized colorant: resin-coated carrier is adjusted to 5:95 (parts by weight) with a mag roll mill. The mixture was mixed and stirred at 1500 rpm for 10 minutes. After stirring, the charge amount was measured with a blow-off device to determine the polarity. The results are shown in Table 1.

The structures of the colorants a and c are as shown in [Chemical Formula 4] and [Chemical Formula 5], and the colorant b is an anthraquinone pigment.

上記分散体１〜３を用いて、下記表３に示す処方で実施例及び比較例の各インクを調合した。 Examples 1-3, Comparative Examples 1-2
Aqueous dispersions 1 to 3 were prepared by mixing the colorants a, b, and c with the dispersant and distilled water at the ratio shown in Table 2 below. Polyoxyethylene-β-naphthyl ether (manufactured by Takemoto Yushi Co., Ltd .: RT-100) was used as the dispersant.

Using the dispersions 1 to 3, inks of Examples and Comparative Examples were prepared according to the formulation shown in Table 3 below.

About these inks, printing evaluation was performed using the printer shown in FIG. The results are shown in Table 3.

  As can be seen from the results in Table 3, in the example, the image was stable over time and a high density image was retained. On the other hand, in the comparative example, the concentration decreased with time. Also, the filter in the head was clogged.

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 2 Main body housing | casing 16 Gear mechanism 17 Subscanning motor 18 Carriage 18a Droplet discharge head 19 Platen 20 Ink cartridge 21 Guide shaft 22 Guide shaft 23 Timing belt 24 Main scanning motor 25 Gear mechanism 26 Main scanning motor 27 Gear mechanism

JP 2008-297526 A JP 2008-38074 A

Claims (5)

  It contains at least colorant A, colorant B, surfactant, water-soluble organic solvent and water, and one of colorant A and colorant B is a pigment and the other is a dye, and colorant A and resin-coated carrier An ink for ink jet recording, wherein the triboelectric charging property is negative and the triboelectric charging property between the colorant B and the resin-coated carrier is positive.   The ink for inkjet recording according to claim 1, wherein the colorant A is a copper phthalocyanine pigment, and the colorant B is an anthraquinone dye.   An inkjet recording method comprising at least an application step of applying a stimulus to the ink for ink jet recording according to claim 1 and an ink flying step of flying the ink to form an image.   An ink cartridge, wherein the ink for ink jet recording according to claim 1 is contained in a container.   In an inkjet recording apparatus having at least an application unit for applying a stimulus to an inkjet recording ink and an ink flying unit for ejecting the inkjet recording ink from an inkjet head to form an image, the nozzle plate surface of the inkjet head is silicone resin or nickel An ink jet recording apparatus comprising an ink repellent layer containing the ink cartridge according to claim 4.

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