JP2001220528A - Recording liquid, method for preparing dispersion for recording liquid, and method for preparing recording liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recording liquid which is especially suitable for ink jet recording, give records with a high print quality even when used in printing on plain paper, enables a high-density recording to be obtained, gives a record having good storage stability and having food fastness such as light resistance and water resistance, is excellent in delivery durability, and does not exhibit blur at the boundaries with other colors, giving food prints. SOLUTION: This recording liquid contains a water-insoluble colorant and a polymeric dispersant (excluding a styrene-acrylic acid copolymer). The average dispersed particle size of the colorant is 0.1-0.3 μm. The dispersant in the form of a free acid is 150 mgKOH/g or higher but lower than 250 mgKOH/g, and the ratio of the dispersant to the colorant is 5 wt.% or higher but lower than 20 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a recording liquid and a method for preparing the same, and more particularly to an aqueous medium recording liquid, particularly a recording liquid suitable for ink jet recording and a method for preparing the same.

[0002]

2. Description of the Related Art For example, Japanese Patent Publication No. Hei 8-19360 discloses an ink jet recording liquid characterized by having a neutral or basic carbon black and a water-soluble resin in an aqueous liquid medium. ing.

However, according to experiments by the present inventors, the above-mentioned ink jet recording liquid can satisfy the long-term storage stability and the ejection stability, but can be used as a recording liquid when printed on plain paper. It has been found that only an extremely insufficient performance can be obtained in terms of the recording density, which is the most important characteristic.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to be particularly suitable for ink-jet recording. Good, high-density recording is possible and storage stability is good, and furthermore, a recorded matter having good fastness of recorded matter such as light resistance and water resistance can be obtained, and excellent ejection durability. It is an object of the present invention to provide a recording liquid which gives a good printed matter without bleeding at a boundary portion between colors and a method for preparing the same.

[0005]

The present inventors have conducted various studies on aqueous dispersion inks. As a result, the recording liquid contains a specific amount of a polymer dispersant having a specific acid value and is dispersed in water. When the average dispersion particle diameter of the insoluble dye is within a relatively large specific range for this type of dispersion, the recording liquid can maintain extremely high recording stability while maintaining excellent ejection stability and storage stability. It has been found that a water-based ink which achieves the density and has no bleeding at the boundary with other colors can be obtained.

[0006] The above-mentioned Japanese Patent Publication No. Hei 8-19360 states, "It is not clear why the dispersion stability is good when the pH of carbon black is neutral or alkaline. The particle size of such a dispersion is small irrespective of the type of dispersant, so that it has excellent ejection properties and does not cause sedimentation or precipitation even during long-term storage. " That is, the invention described in the above publication is aimed at improving the ejection stability and storage stability, and the above publication does not specifically describe the dispersed particle size of the pigment in the dispersion, but rather, It is described that the smaller the dispersed particle size, the better the ejection property and the storage stability.

[0007] As described above, the conventional known documents including the above-mentioned publications suggest no technical idea of improving the recording density by adjusting the dispersed particle diameter of the pigment in the dispersion to a specific range. Not.

The present invention has been completed on the basis of the above-described novel findings. The first gist of the present invention is to provide a water-insoluble dye and a polymer dispersant (provided that a styrene-acrylic acid copolymer is used). ), Wherein the water-insoluble dye has an average dispersed particle size of 0.1 to 0.3 µm, and the polymer dispersant has an acid value in the form of free acid of 150 mgKOH / g.
And less than 250 mgKOH / g, and the ratio of the high molecular weight acid-soluble agent to the water-insoluble dye is from 5% by weight to less than 20% by weight.

The second aspect of the present invention is a method for preparing a dispersion for a recording liquid in which a water-insoluble dye is dispersed in a medium in the presence of a water-soluble polymer. The acid value in the form of the free acid is at least 150 mg KOH / g 2
Using a polymer dispersant of less than 50 mgKOH / g (however, excluding a styrene-acrylic acid copolymer), the average dispersion particle size of the water-insoluble dye in the dispersion is from 0.1 to 0.1.
The present invention relates to a method for preparing a recording liquid dispersion, characterized in that it is adjusted to a range of 3 μm.

A third aspect of the present invention is a method for preparing a recording liquid in which a water-insoluble dye is dispersed in a medium in the presence of a water-soluble polymer. Acid value in the form of free acid is 150 mg KOH / g or more 2
Using a polymer dispersant of less than 50 mgKOH / g (excluding a styrene-acrylic acid copolymer), the average dispersion particle size of the water-insoluble dye in the recording liquid is 0.1 to 0.1.
A method for preparing a recording liquid, characterized in that the recording liquid is adjusted to a range of 3 μm.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
Examples of the water-insoluble dye used in the present invention include organic pigments, inorganic pigments, disperse dyes, and oil-soluble dyes. These specific examples are as follows.

The pigments used for the yellow ink include C.I. I. Pigment Yellow 1, 2, 3, 12,
13, 14, 16, 17, 73, 74, 75, 83, 9
3, 95, 97, 98, 114, 128, 129,
151, 154 and the like. Specific examples of the pigment used in the magenta ink include C.I. I. Pigment Red 5, 7, 12, 48 (Ca), C.I. I. 48 (M
n), 57 (Ca), 57: 1, 112, 123, 1
68, 184, 202 and the like. Specific examples of the pigment used for the cyan ink include C.I. I. Pigment Blue 1, 2, 3, 15: 3, 15:34, 1
6, 22, 60, 4, 60 and the like.

In addition to the above, C.I. I. Pigment Red 20
9, 122, 224, 177, 194, C.I. I.
Pigment Orange 43, C.I. I. Bat violet 3, C.I. I. Pigment Violet 19, 23, 3
7, C.I. I. Pigment Green 36, 7, C.I. I.
Pigment Blue 15: 6, 209 and the like can also be used.

The oil-soluble dyes include C.I. I. Solvent Yellow 16, 21, 25, 29, 33, 56, 82,
88, 89, 150, 151, 163, C.I. I. Solvent Red 24, 27, C.I. I. Solvent Blue 14, 25, 38, 48, 67, 68, 70, 132
, C.I. I. Solvent Black 3, 5, 7, 27,
28, 29, 34, etc. can be used.

Other oil-soluble dyes other than those described above include oil yellow 105, 107, varifast yellow 1101, 1105, varifast red 1306, varifast blue 1603, 1607, 2610, and varifast black 1802, 1807, 3830 ( Above, Orient Chemical Industries Co., Ltd.), Aizen Spiron Yellow GRLH, 3RH, Aizen Spiron Blue GNH
, 2BNH, BPNH, Aizenspiron Black MH, GMH
(Above, manufactured by Hodogaya Chemical Industry Co., Ltd.), Oleosol Blue G, Oleosol Black AR (above, manufactured by Taoka Chemical Industry Co., Ltd.), Olasol Black RL1 (manufactured by Ciba Geigy), and the like.

As the disperse dye, C.I. I. Disperse Yellow 3, 82, 54, C.I. I. Disperse threads 60 and 191, disperse vilet 57 and the like.

In the present invention, various carbon blacks such as acetylene black, channel black and furnace black can be used as the water-insoluble dye. Of these, channel black or furnace black is preferred, and furnace black is particularly preferred.

The above-mentioned carbon black preferably has a DBP oil absorption of 140 ml / 100 g or more, particularly 145 ml / 100 g.
It is preferably at least ml / 100 g. The volatile content is preferably 8% by weight or less, particularly preferably 4% by weight or less. pH is
Usually, it is 1 to 14, but from the viewpoint of storage stability of the recording liquid, 3 to 11 is preferable, and 6 to 9 is particularly preferable. BE
The T specific surface area is usually 200 m ² / g or more.
It is preferably from 50 to 400 m ² / g, especially from 250 to 320
m ² / g is preferred. The primary particle size is usually 20 nm or less, preferably 16 nm or less, particularly preferably 15 nm or less. Here, the DBP oil absorption is based on JIS K62.
The value measured by the 21 A method and the volatile content are the values measured by the method of JIS K6221. The primary particle diameter is the arithmetic average diameter (number average) measured by an electron microscope.

Specific examples of the above carbon black include Color Black FW1, FW2, FW2
V, FW18, FW200, Special Black
6, Color Black S170 (product of Degussa), CONDUCTEX975ULTRA (product of Colombian) and the like.

In the present invention, the above-mentioned water-insoluble coloring material which has been chemically treated (oxidation treatment, fluorination treatment, etc.), a dispersant, a surfactant and the like are physically or chemically bound. (Eg, a grafting treatment, a dispersant previously adsorbed before dispersion) and the like can be used. In the present invention, among the above water-insoluble dyes, carbon black is particularly preferably used.

The polymer dispersant used in the present invention is other than a styrene-acrylic acid copolymer and has an acid value in the form of free acid of 150 mgKOH / g to 250 mgKO.
It is a copolymer of less than H / g. The above acid value is 180 m
gKOH / g or more is preferable, and 200 mgKOH / g or more is particularly preferable. When the acid value exceeds 250 mgKOH / g, the water resistance of the recorded matter is deteriorated.
If it is less than 0 mgKOH, the water-insoluble dye cannot be sufficiently dispersed in the aqueous medium.

The polymer dispersant used in the present invention has an acid value in the form of a free acid within the above range and may be any other than a styrene-acrylic acid copolymer. Is preferably an amphipathic polymer comprising both a hydrophobic vinyl monomer component and an anionic vinyl monomer component. The hydrophobic vinyl monomer constituting the polymer dispersant of the present invention includes an optionally substituted phenyl group, a benzyl group, a functional group having an aromatic ring such as a naphthyl group, a branched or cyclic group having 4 or more carbon atoms. Alternatively, it is a vinyl compound having an optionally substituted alkyl group, alkenyl group, or alkynyl group. Specific examples of the hydrophobic vinyl monomer include, for example, styrenes such as styrene and α-methylstyrene, and aromatic (meth) acrylates such as benzyl (meth) acrylate and naphthyl (meth) acrylate. And methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, (meth)
Aliphatic esters of (meth) acrylic acid such as 2-ethylhexyl acrylate, lauryl (meth) acrylate, and stearyl (meth) acrylate; and (meth) acrylic acid benzylamide and (meth) acrylic acid naphthylamide and the like (Meth) acrylic acid aromatic amide, (meth) acrylic acid methylamide, (meth) acrylic acid ethylamide, (meth) acrylic acid butylamide, (meth) acrylic acid-2-ethylhexylamide, (meth) acrylic acid laurylamide, Preferred are (meth) acrylic acid aliphatic amides such as (meth) acrylic acid stearylamide, or (half) esters and (half) amides using maleic acid instead of (meth) acrylic acid in the above specific examples. Can be illustrated. As the anionic vinyl monomer constituting the polymer dispersant of the present invention, a known anionic vinyl monomer having both an anionic functional group and a vinyl group in one molecule can be used. Examples of the anionic vinyl monomer used in the present invention include (meth)
Acrylic acid, maleic acid, acrylamide-2-methylsulfonic acid (AMPS)...

Specific examples of such a polymer dispersant include:
(Α-methyl) styrene / maleic acid copolymer, (meth) acrylate / (meth) acrylic acid copolymer, (meth) acrylate / maleic acid copolymer, (meth) acrylate / AMPS Copolymers and / or salts thereof are exemplified. Here, (α-methyl) styrene refers to α-methylstyrene and / or styrene, and (meth) acrylic acid refers to methacrylic acid and / or acrylic acid.

The polymer dispersant used in the present invention may be any of a block polymer, a graft polymer and a random polymer, but the graft polymer and the random polymer are preferred mainly in view of production cost, and the random polymer is preferably used. More preferred. The weight average molecular weight of the polymer dispersant used in the present invention is preferably 50,000 or less, from the viewpoint of ejection stability, more preferably 15,000 or less, and particularly preferably 10,000 or less. . These polymer dispersants include alkali metal salts such as Li, Na, and K, ammonia, dimethylamine,
r It can be used in the form of an organic amine salt such as triethanolamine.

In the recording liquid of the present invention, other additives such as a surface tension adjuster, a preservative, a fungicide, a bactericide, a pH adjuster, and urea may be used as necessary. Examples of such additives include various anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants,
Polymer-based dispersants and the like can be mentioned.

Examples of the anionic surfactant include fatty acid salts, alkyl sulfate salts, alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl sulfosuccinates, alkyl diphenyl ether disulfonates, alkyl phosphates, and polyoxyethylene. Alkyl sulfates, polyoxyethylene alkylaryl sulfates, alkane sulfonates, naphthalene sulfonic acid formalin condensates, polyoxyethylene alkyl phosphates, N-methyl-N-oleoyl taurate, α- Olefin sulfonates and the like.

The nonionic surfactant is not particularly limited, but preferably has an ethylene oxide structure or a propylene oxide structure from the viewpoints of storage stability and print density. ~ 16 are more preferred.

Specific examples of the nonionic surfactant include:
Polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene alkyl ether, polyoxyethylene lauryl ether, polyoxyethylene oleyl ether, polyoxyethylene tridecyl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether , Polyoxyethylene alkylamine, aminopolyoxyethylene, sorbitan fatty acid ester, polyoxyethylene sorbitan laurate, polyoxyethylene sorbitan palmitate, polyoxyethylene sorbitan stearate, polyoxyethylene sorbitan oleate, naphthol ethylene oxide adduct, acetylene Glycol ethylene oxide adduct with bisphenol A ethylene oxide Things, oxyethylene oxypropylene block polymer, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene alkylamines, and the like.

On the other hand, examples of the cationic surfactant and the amphoteric surfactant include alkylamine salts, quaternary ammonium salts, alkylbetaines, and aminooxides.

As the medium of the recording liquid of the present invention, an aqueous medium mainly composed of water is usually used. In this case, it is preferable to add a water-soluble organic solvent to water.

Examples of the water-soluble organic solvent include ethylene glycol, propylene glycol, 1,3-propanediol, butylene glycol, diethylene glycol, triethylene glycol and polyethylene glycol (specific examples: “# 200” manufactured by Wako Pure Chemical Industries, Ltd. "# 300",
“# 400”, “# 4000”, “# 6000”), glycerin, an ethylene glycol adduct of glycerin (specific example: “Liponic EG-1” manufactured by Lipochemical Co., Ltd.)
Alkyl ethers of the above glycols (diethylene glycol monoethyl ether, triethylene glycol monoethyl ether, diethylene glycol monopropyl ether, triethylene glycol monopropyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, polyethylene glycol monopropyl ether) , Polyethylene glycol monobutyl ether, polyethylene glycol monostearyl ether, etc.), N-methylpyrrolidone, 1,3-dimethylimidazolinone, thiodiglycol, 2-pyrrolidone, sulfolane, dimethylsulfoxide, diethanolamine, triethanolamine, methanol, ethanol, Isopropanol, neopentyl alcohol, trime Trimethylolpropane, 2,2-dimethyl propanol.

The recording liquid of the present invention is obtained by subjecting a water-insoluble dye to a dispersion treatment in a medium in the presence of a water-soluble polymer in accordance with a known method to obtain a high-concentration dispersion. To prepare a recording liquid by adding a medium to the medium and adjusting the concentration (master batch method) or a method of preparing a recording liquid by dispersing a water-insoluble dye in the medium in the presence of a water-soluble polymer. can get. The above-described master batch method is efficient because the dispersion treatment is performed at a high concentration.

As a dispersing machine used for the dispersion treatment, a ball mill, a roll mill, a sand grind mill, and a jet mill such as a nanomizer and an ultimizer which can be pulverized without using a medium are used. In particular, a sand grind mill or a jet mill with less contamination from media is preferred. In the present invention, coarse particles are removed by a filter or a centrifugal separator after the above-mentioned grinding and dispersion treatment by the disperser.

The recording liquid of the present invention is characterized by containing the above-mentioned water-insoluble dye and a polymer dispersant having a specific acid value. The ratio of the polymer dispersant to the water-insoluble dye is set to 5% by weight or more and less than 20% by weight. By satisfying such conditions, the storage stability of the recording liquid is improved. The ratio of the polymer dispersant to the water-insoluble dye is preferably in the range of 8 to 15% by weight.
On the other hand, the amount of the water-insoluble dye used is based on the total weight of the recording liquid.
Usually, it is in the range of 1 to 10% by weight, preferably 3 to 8% by weight. The amount of the water-soluble organic solvent used is usually 5 to 30% by weight, preferably 5 to 30% by weight in the recording liquid.
The range is 20% by weight, more preferably 8 to 20% by weight.

The greatest feature of the recording liquid of the present invention resides in that the average dispersed particle size of the water-insoluble dye is 0.1 to 0.3 μm. In the above-mentioned master batch method, in the dispersion obtained by the dispersion treatment, the average dispersed particle size of the water-insoluble dye must be in the above range. By adjusting the average dispersed particle size of the water-insoluble dye to the above range,
The dispersion stability and ejection stability of the recording liquid are improved, and a favorable result is obtained in terms of recording density. The average dispersed particle size of the water-insoluble dye is preferably from 0.1 to 0.1.
2 μm, more preferably 0.12 to 0.18 μm.

Further, the maximum particle size of the water-insoluble dye in the recording liquid is more preferably 5 μm or less from the viewpoint of dispersion stability and ejection stability. The standard deviation in the dispersion particle size distribution of the water-insoluble dye is 70 nm or less, preferably 5 to 60 nm, more preferably 10 to 50 nm, from the viewpoints of storage stability, ejection stability, and recording density.

However, in the present invention, the average dispersed particle size and the dispersed particle size distribution of the water-insoluble dye in the recording liquid were measured using a submicron particle analyzer N4S (a product of Coulter).
And the value measured in.

Since the recording liquid of the present invention has the above-mentioned characteristics, it can be used as a recording liquid for other purposes, not limited to ink jet and writing instruments. The recording liquid of the present invention is particularly suitable for ink-jet recording, and can be used in all types of ink-jet recording methods (on-demand method, continuous method, piezo method, thermal method), and all recording materials (plain paper) , Recycled paper, inkjet paper (coated paper, glossy paper, etc.), inkjet dedicated film (coated film, glossy film, etc.), OHP film, etc.

[0039]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist. In the following examples, “parts” and “%” are based on weight. The type of carbon black used is as shown in Table 1 below.

[0040]

[Table 1]

(1) Printing test: The recording liquid obtained in the above-mentioned Example 1 was applied to "DeskJe" manufactured by Hewlett-Packard.
t895Cxi ”(Black cartridge HP5164
5A) and electrophotographic paper (Xerox 4024)
Paper, Xerox 4200 paper, Xerox product) in the normal mode.

(2) Evaluation of Print Density The density of the printed matter obtained in the above print test was measured with a Macbeth reflection densitometer (RD914), and those having a measured value exceeding 1.4 were judged to be excellent. Table 6 shows the results.

(3) Bleeding test: A recording liquid was charged into a DeskJet 895Cxi (black cartridge HP51645A) manufactured by Hewlett-Packard, and electrophotographic paper (Xerox 4024 paper, Xerox 42) was used.
00 product and Xerox product) were solid-printed in yellow, magenta, and cyan, respectively, so that the borders were in contact with the color inks. After the ink was dried, the bleeding (bleeding) at the boundary between the color ink and the black ink was observed and evaluated visually. The evaluation criteria are as shown in Table 2 below.

[0044]

[Table 2] ・ ・ ・: No bleeding at the color boundary. Δ: Slight bleeding at the color boundary. ×: Bleeding at the color boundary is severe.

(4) Water resistance test: The printed matter obtained in the printing test was immersed in tap water collected in a beaker for 5 seconds. After the printed matter was dried, the presence or absence of background stain was visually evaluated. The evaluation criteria are as shown in Table 3 below.

[0046]

[Table 3] ○ · · · almost no character stain. Δ: There is a slight character stain, but there is no practical problem. ×: The character stain is terrible.

(5) Dispersion particle size distribution measurement: The recording liquid was diluted with ion-exchanged water, and the dispersion particle size distribution was measured using a particle size distribution meter (Coulter product “Particle Analyzer N4S”). The measurement conditions are as shown in Table 4 below. The average of the three measurements was taken as the average dispersed particle size.

[0048]

Table 4 Temperature = 25 ° C Viscosity = 0.894 cP Refractive index = 1.333 Angle = 90.0 ° Sampling time = 13.5 microseconds Prescale = 2 Total sampling time = 60 seconds

Example 1 The components shown in the following Table 5 were collected in a cylindrical stainless steel container, and subjected to a dispersion treatment for 3 hours by a sand grinder together with 74.5 g of zirconia beads having an average diameter of 0.5 mm.

[0050]

Table 5 Composition of recording liquid Amount used (parts) Carbon black (A) 2.5 Polymer dispersant (B) 0.25 Glycerin 2.75 Ion-exchanged water 16.5 Total 22 Note) Polymer dispersant (B) = benzyl methacrylate / acrylamide-2-methylsulfonic acid / acrylic acid copolymer (random copolymer, monomer weight ratio 50/30/2)
0, ammonium salt having a weight average molecular weight of 3100 and an acid value of 237)

The obtained liquid was mixed with 2.5 parts of polyethylene glycol (“# 400” manufactured by Wako Pure Chemical Industries, Ltd.) and deionized water 2
An additional 5.5 parts were added. This solution was The solution was filtered under pressure through 5C filter paper, and the obtained liquid was used as a recording liquid. The average dispersion particle size of carbon black in the obtained recording liquid was 0.13.
It was 5 μm. As a result of the printing test, the recording liquid showed stable and good dischargeability without clogging or the like. In addition, a printed matter having good print quality was obtained. Other test results
The results are shown in Tables 6 and 7.

Example 2 In Example 1, "Color Black FW18" manufactured by Degussa was used instead of carbon black (A).
A recording liquid was prepared in the same manner as in Example 1 except that was used. The same evaluation as in Example 1 was performed on the obtained recording liquid. The average dispersion particle size of carbon black in the obtained recording liquid was 0.126 μm. As a result of the printing test,
The recording liquid showed stable and good dischargeability without clogging or the like. In addition, a printed matter having good print quality was obtained. Other test results are shown in Tables 6 and 7.

Comparative Example 1 The procedure of Example 1 was repeated except that the amount of the polymer dispersant used in Example 1 was 0.75 parts, the amount of ion-exchanged water was 16.0 parts, and the dispersion time was 30 hours. A recording solution was prepared in the same manner as in Example 1. The average dispersion particle size of the obtained recording liquid was 0.09.
The same evaluation as in the above example was performed using the obtained recording liquid. The results are shown in Tables 6 and 7 below.

Comparative Example 2 In place of the carbon black (A) used in Example 1, C
The same as Example 1 except that the amount of the polymer dispersant was 0.75 parts, the amount of ion-exchanged water was 16.0 parts, and the dispersion time was 30 hours using color BlackFW18 (a product of Degussa). A recording solution was prepared by the method described in (1). The average dispersion particle size of the obtained recording liquid is 0.096 μm,
The same evaluation as in the above example was performed using the obtained recording liquid. The results are shown in Tables 6 and 7 below.

[0055]

[Table 6]

[0056]

[Table 7]

[0057]

According to the present invention described above, the present invention is particularly suitable for ink-jet recording, and when printed on plain paper, the print quality of the recorded matter is good, and high-density recording is possible and storage is possible. Good printed matter with good stability and good fastness of recorded matter such as light fastness and water resistance, excellent discharge durability, and no bleeding at the boundary with other colors And a method for preparing the same.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C056 EA13 FC01 2H086 BA55 BA59 BA60 4J039 BA04 BE01 BE02 BE22 CA06 GA24

Claims (6)

[Claims] 1. A recording liquid containing a water-insoluble dye and a polymer dispersant (excluding a styrene-acrylic acid copolymer), wherein the water-insoluble dye has an average dispersed particle size of 0.1 to 0.1.
0.3 μm, the acid value of the polymer in the form of a free acid is 150 mgKOH / g or more and less than 250 mgKOH / g, and the ratio of the polymer dispersant to the water-insoluble dye is 5% by weight or more and 20% by weight or less. A recording liquid characterized by being less than 2. The recording liquid according to claim 1, wherein the water-insoluble dye is carbon black. 3. The carbon black has a nitrogen adsorption specific surface area of 200 m ² / g or more and a DBP oil absorption of 140 ml / 10.
The recording liquid according to claim 2, wherein the recording liquid is 0 g or more. 4. The method according to claim 1, which is for ink jet recording.
3. The recording liquid according to any one of 3. 5. A method for preparing a dispersion for a recording liquid, comprising dispersing a water-insoluble dye in a medium in the presence of a water-soluble polymer, wherein the water-soluble polymer is in the form of a free acid. Using a polymer dispersant having an acid value of 150 mgKOH / g or more and less than 250 mgKOH / g (however, excluding a styrene-acrylic acid-based copolymer), the average dispersion particle size of the water-insoluble dye in the dispersion is adjusted to 0.1. A method for preparing a recording liquid dispersion, which is adjusted to a range of from 0.3 to 0.3 μm. 6. A method for preparing a recording liquid in which a water-insoluble dye is dispersed in a medium in the presence of a water-soluble polymer, wherein the water-soluble polymer has an acid value in the form of a free acid. 150
The average disperse particle size of the water-insoluble dye in the recording liquid is from 0.1 to 0.1 mg / ml using a polymer dispersant (excluding a styrene-acrylic acid-based copolymer) of from mgKOH / g to less than 250 mgKOH / g. A method for preparing a recording liquid, wherein the recording liquid is adjusted to a range of 3 μm.