JP2000239587A - Recording liquid, printing article using the same, and method for ink-jet recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous ink giving high printing density and stable recorded images when used for ink-jet printing or a writing article and having good storage stability and issuing stability. SOLUTION: This ink gives a SAD(Surface Area Difference) value of >=59.5 to a printed part, when the ink is used for printing the part on an electrophotographic paper, which has a SAD value within the range of 6.0-9.0 and a pH value within the range of 6-8, with a resolution of 600×300 dpi(dots per inch) and 100% Duty.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording liquid for an aqueous medium, and more particularly to a recording liquid for an ink jet or a writing instrument, and more particularly to a recording liquid suitable for an ink jet.

[0002]

2. Description of the Related Art Conventionally, as a recording liquid for ink jet recording, an aqueous ink in which an acidic dye or a direct dye is dissolved in an aqueous medium, or a solvent-based ink in which an oil-soluble dye is dissolved in an organic solvent has been used. . Since the solvent-based ink uses a solvent, it has a problem in terms of environmental safety, and its use is limited because it is not suitable for use in offices and the like. On the other hand, since the water-based ink uses a water-soluble dye, there is a problem that the water resistance of the recorded matter is inferior especially when recording is performed on plain paper. Further, the recorded matter of the ink using these dyes is insufficient in light resistance. Such a problem applies not only to the recording liquid for ink jet recording but also to the recording liquid for writing implements.

In order to solve the above-mentioned problems, a water-insoluble dye having excellent water resistance and light fastness is used as a coloring material, and an aqueous dispersion ink in which the water-insoluble dye is dispersed in an aqueous medium is used in part. ing. However, in the conventional aqueous dispersion ink of a water-insoluble dye, the long-term storability and the recording density of the recorded matter are insufficient. It is difficult to achieve both properties such as storage stability and ejection stability of the liquid, and further improvement has been desired.

[0004]

DISCLOSURE OF THE INVENTION The present invention is intended for use in ink jet recording or writing instruments, and has a good print quality and high-density recording even when recorded on plain paper or recycled paper, and has storage stability. Is good, light fastness,
It is an object of the present invention to provide a water-based ink having excellent durability such as water resistance and excellent durability.

[0005]

Means for Solving the Problems The present inventors have conducted various studies on the improvement of the print density of an aqueous dispersion black ink using a water-insoluble dye, and found that the S.P. A. D. It has been found that (Surface Area Difference) correlates with both the storage stability of the recording liquid, the printing unevenness of the printed matter, and the recording density, and has a great effect, and has reached the present invention. According to the present invention, it is possible to obtain a recording liquid that simultaneously satisfies both the good printing density of a recorded matter and the storage stability and ejection stability of the recording liquid. That is, the gist of the present invention is as follows. A. D. (Surface Area Difference
) Is in the range of 6.0 to 9.0 and the pH is in the range of 6 to 8 in the printing section when printing is performed at a resolution of 600 × 300 dpi and 100% duty on electrophotographic paper. . A. D. Is 59.5 or more.

[0006] In short, the present invention relates to the S.P. A. D.
Defines a recording liquid having a specific range. However, in the case of a conventionally available inkjet recording liquid, the S.D. A. D. The value was at most about 59.2.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The S.S. A. D. (Surface Area Differe
“nce” indicates the specific surface area of the recorded matter, and is a parameter defined by the following equation. In the present invention, the measurement method employs the following conditions.

[0008]

SAD (Surface Area Difference) = ｛(DifferenceSi
/ {Pi) -1} × 100 (%) Si: Area of all triangles formed by three adjacent data points Pi: Area when Si is projected on xy plane ΣSi: Sum of all Si ΣPi: All Pi Sum

[0009]

[Table 1] (Measurement method) Apparatus: Scanning Probe Microscope Model: Digital Instruments NanoScope III Scanner: J-Head Measurement area: 1 μm × 1 μm Number of pixels: 512 × 512 Scan Rate: 1.5 Hz Measurement mode: Tapping AFM search Needle: Seiko Instruments Inc. Si-DF 20 Surface image processing: Planefit Auto Tertiary

In the present invention, S.D. A. D is 6.0 to 6.0
In an electrophotographic paper having a pH in the range of 9.0 and a pH in the range of 6 to 8, for example, 4024 paper (Xerox standard) at a resolution of 600 × 300 dpi and 10
Printing was performed at 0% duty, and the surface of the printed portion was measured using the above measurement conditions. A. Calculate D. The measurement area is a part avoiding the fiber part of the paper, and the data is averaged at four points (four areas). Also, the above 4024
The paper is an electrophotographic paper containing rosin-based abietic acid as a sizing agent and containing 1.8 to 2.2% by weight of Ti atoms in the paper.

As described above, in the present invention, the S.P. A.
D. Is 59.5 or more, but 60.0 or more, and more preferably 62.0 or more in terms of improving the recording density.
As described above, it is particularly preferable to be 65.0 or more. However, considering the abrasion property, S.P. A. D. Is preferably 90.0 or less, more preferably 85.0 or less, particularly preferably 80.0 or less, and more preferably 70.0 or less. That is,
In consideration of the overall performance of the recording liquid, the higher the value of SAD, the better. It is preferable that the value be in the specific range described above. A. D. Of the optimum range. When the recording liquid of the present invention was used, it was found that high density printing of 1.5 or more in density OD of a printed matter measured using a Macbeth reflection densitometer (RD914) was achieved.

[0012] The recording liquid of the present invention has a performance in which the storage stability of the recording liquid is better than that of a conventional recording liquid.
It is characterized in that the recording liquid has a small variation in particle size distribution when stored at a high temperature for a long time. Specifically, a comparison was made between the particle size distribution measured immediately after preparing the recording liquid and the particle size distribution measured after storing the recording liquid at 70 ° C. for one week, and the difference was calculated for each fraction of the measured particle diameter. Is not more than 20%, preferably 1 to 18%, taking into account the measurement error,
More preferably, it is possible to provide a recording liquid in the range of 2 to 15%. If the total value is too small, it is not preferable because coagulation on the recording paper at the time of recording is poor, the print density is low, and print unevenness tends to occur. Particle size distribution of the recording liquid in the present invention,
The method of calculating the sum of the differences in the particle size distribution after storing the recording liquid at 70 ° C. for one week is as follows.

Measurement of Particle Size Distribution Immediately After Preparation of Recording Solution First, the recording solution immediately after preparation is used at the same concentration, and measurement is performed with a particle size distribution meter (MicrotracUPA (Nikkiso sales)) under the following conditions.

[0014]

[Table 2] Measurement conditions (input parameters) Transparent Particles: No, Spherical Particles:
No, Particle Refractive Index: 1.81 Particle Density: 1.86 Fluid Refractive Index: 1.33 High Temp: 30.0 ℃ Viscosity: 0.797 cP Low Temp: 20.0 ℃ Viscosity: 1.002 cP Run Time: 300 (sec), Number of Runs: 2

The average of two measurements under the above measurement conditions is defined as the value of the particle size distribution of the recording liquid.

Measurement of the particle size distribution of the recording liquid after storage at 70 ° C. for 1 week The recording liquid is stored at 70 ° C. for 1 week, returned to room temperature after storage, and maintained at the same concentration as in the particle size distribution meter (MicrotracUPA (Nikkiso sales)). )), The particle size distribution is measured in the same manner as described above, and the average of the two measurements is taken as the value of the particle size distribution of the recording liquid. Is compared with the result, and the difference is calculated for each fraction of the measured particle size, and the total is calculated.

The reason why the recording liquid of the present invention has the preferable performance as described above is not clear, but is presumed as follows. When the recording liquid of the present invention is recorded on a recording material (paper, film, or the like), the water-insoluble coloring material contained therein rapidly aggregates, and as a result, the SAD on the surface of the printing portion is 59.5. It is considered that high recording density can be realized because of the above. On the other hand, the recording liquid of the present invention causes agglomeration on the recording material, but does not cause agglomeration during storage of the recording liquid, so that a stable recorded matter can be always obtained.
Conventional recording liquids do not have such seemingly contradictory properties in an appropriate range. Conversely, in the field of paint,
Generally, it is considered that the smoother the printing portion surface (that is, the smaller the SAD) is, the higher the printing density is. A. D. It was not considered at all that the larger the is, the higher the print density was. The present application is a new discovery that was not considered from conventional common sense.

In the present invention, S.D. A. D. (Surfac
e Area Difference) is within the range of 6.0 to 9.0 or the pH of the electrophotographic paper is within the range of 6 to 8 at a resolution of 600 × 300 dpi and 100% D.
S. of the printing part when printing in U.T. A. D. (Surfac
Although the characteristics of the recording liquid are defined using e Area Difference) as an index, printing may be performed on any type of recording paper as long as the recording liquid satisfies such a specification. For example, when the recording liquid of the present invention is used in an ink jet recording method, the recording paper is, for example, plain paper (Xerox 4024, Xerox 42) such as electrophotographic paper as the recording paper.
00, Canon PB, Canon LC-301,
Canon CP-250, Epson KA4250
NP, etc.), recycled paper (Xerox Green10)
0, Xerox R, etc.), coated paper (Canon HR)
-101s, Lexmark 1402650, Lex
mark 1402781, HP 51634Z, etc.),
Glossy paper (Canon GP-201, Canon GP
-101, Canon HG-101, Canon HG
-201, Canon BF-102, Canon K
H-201, Epson MJA4SP6, Epson
MJSP5,. Lexmark 1402796, L
exmark 1372361, Lexmark 13
72208, HP C6043A, HP C5984A
Etc.), OHP film (CanonCF-102, Ep)
son MOHPS1N, Lexmark 1402
798, HP C3835A).

Various additives can be used in the recording liquid of the present invention. For example, a dispersant may be used. The dispersant that can be used is not particularly limited as long as it is a known dispersant, but various anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, polymer dispersions Agents and the like. 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,
Examples include polyoxyethylene alkyl sulfate salts, polyoxyethylene alkyl aryl sulfate salts, alkane sulfonates, naphthalene sulfonic acid formalin condensates, polyoxyethylene alkyl phosphates, α-olefin sulfonates, and the like.

Nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl aryl ethers, polyoxyethylene derivatives, oxyethylene / oxypropylene block copolymers, sorbitan fatty acid esters, polyoxyethylene sorbitan Examples thereof include fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, polyoxyethylene fatty acid esters, and polyoxyethylene alkylamines.

Examples of the cationic surfactant and the amphoteric surfactant include alkylamine salts, quaternary ammonium salts, alkylbetaines, and aminooxides. Further, as a polymer dispersant, polyacrylic acid,
(Α-methyl) styrene / (meth) acrylic acid copolymer, (α-methyl) styrene / (meth) acrylic acid /
(Meth) acrylate copolymer, (α-methyl)
Styrene / maleic acid copolymer, (α-methyl) styrene / maleic acid / (meth) acrylate copolymer, (α-methyl) styrene / methacrylic acid copolymer,
(Α-methyl) styrene / methacrylic acid / (meth) acrylate copolymer, (α-methyl) styrene / maleic acid half ester copolymer, α-olefin / allyl ether / maleic acid copolymer, (α -Methyl) styrene / (α-methyl) styrenesulfonic acid copolymer, vinylnaphthalene / maleic acid copolymer, vinylnaphthalene / (meth) acrylic acid copolymer or salts thereof (alkali such as lithium, sodium and potassium) Metal salts, triethanolamine, monoethanolamine,
Organic amine salts such as 2-amino-2-propyl alcohol). However, (meth) acrylic acid refers to acrylic acid and / or methacrylic acid, and (α-methyl) styrene refers to styrene and / or α-methylstyrene. These polymeric dispersants are particularly excellent. Among them, a polymer that functions as a dispersant and a binder for improving scratch resistance can be used. Particularly in terms of the abrasion resistance of the recorded matter, block polymers, graft polymers,
A polymer to which a polymer such as a random polymer is added is preferable, but a graft polymer and a random polymer are preferable in terms of production cost, and a random polymer is more preferable. The weight average molecular weight of these polymers is preferably 50,000 or less, more preferably 15,000 or less, from the viewpoint of ejection stability of the obtained recording liquid.

Among these polymers, carboxylic acids (salts)
Anionic polymer having an anionic water-soluble group selected from sulfonic acid (salt) group and phosphoric acid (salt) group can be preferably used, but a polymer having a hydrophobic group or pKa
The polymer having an anionic water-soluble group of 3 or less is more preferable in terms of storage stability and ejection stability. Among them, a polymer having a carboxylic acid (salt) group or a sulfonic acid (salt) group is most preferable in terms of ejection stability and dispersibility, and a polymer having a sulfonic acid (salt) group is particularly preferable. In the present invention, an anionic polymer, a nonionic polymer, an amphoteric (betaine type) polymer, a cationic type polymer, a resin emulsion, or the like may be added as a binder.

The hydrophobic group in the anionic polymer includes
Has an aromatic ring such as a phenyl, benzyl, or naphthyl group
Functional group, straight-chain or branched having 4 or more carbon atoms, substituted
Alkyl group, alkenyl group, alkynyl group
No. Anionic polymer that can be used in the present invention,
Specifically, styrene / acrylic acid copolymer, styrene
/ Acrylic acid / acrylate copolymer, styrene
/ Maleic acid copolymer, styrene / maleic acid / acrylic
Acrylate copolymer, styrene / methacrylic acid copolymer
Body, styrene / methacrylic acid / acrylic acid ester copolymer
Coalesce, styrene / maleic acid half ester copolymer,
Styrene / styrene sulfonic acid (salt) copolymer, vinyl
Lunaphthalene / maleic acid copolymer, vinylnaphthalene
/ Acrylic acid copolymer, naphthalene sulfonate forma
Phosphorus condensates, ligninsulfonic acid, or
And the like. Above all, styrene / acrylic acid copolymer
Coalescence, styrene / acrylic acid / acrylic acid ester copolymer
Coalesce, styrene / maleic acid copolymer, styrene / male
Inic acid / acrylate copolymer, styrene / meta
Crylic acid copolymer, styrene / methacrylic acid / acrylic
Acid ester copolymer, styrene / maleic acid half S
Ter copolymer, styrene / styrenesulfonic acid (salt)
Copolymers are more preferred. Furthermore, the color tone is good,
In order to obtain a printed product without these, these anionic polymers
380 to 780 nm
The maximum value of the absorbance in the range of 0.05 g ^-1・ L ・ c
m^-1Below, especially 0.01 g^-1・ L ・ cm^-1The following
Is preferred.

The recording liquid of the present invention may further contain other additives such as a surface tension adjusting agent and a preservative. In the present invention, the above-mentioned anionic polymer and the above-mentioned nonionic additive can be used in combination. In that case, the content ratio between the anionic polymer and the nonionic additive is 12: 1.
-1: 1, preferably 10: 1 to 2: 1 in terms of storage stability and print density.

Examples of the water-insoluble dye used in the present invention include organic pigments, inorganic pigments, disperse dyes, oil-soluble dyes and the like, and specific examples include the following. Specific examples of the pigment used in the yellow ink include CI Pigment Yellow 1, 2, 3, 12, 13, 14, 16, 17, 73, and 7
4, 75, 83, 93, 95, 97, 98, 114, 128, 129, 151
, 154 and the like.

Specific examples of the pigment used in the magenta ink include CI Pigment Red 5, 7, 12, 48.
(Ca), 48 (Mn), 57 (Ca), 57: 1, 112, 123, 168, 184
, 202 and the like. Specific examples of pigments used for cyan ink include CI Pigment Blue 1, 2, 3
, 15: 3, 15:34, 16, 22, 60, CI Bat Blue 4, 6
0 and the like. In addition to the above, CI Pigment Red 2
09, 122, 224, 177, 194, CI Bat Violet 43, CI Bat Violet 3, CI Pigment Violet 19, 23, 37, CI Pigment Green 36, 7,
CI Pigment Proof 15: 6, 209 etc. can also be used.

The oil-soluble dyes include CI Solvent Yellow 16, 21, 25, 29, 33, 56, 82, 88, 89, 150, 151,
163, CI Solvent Red 24, 27, CI Solvent Blue 14, 25, 38, 48, 67, 68, 70, 132, CI Solvent Black 3, 5, 7, 27, 28, 29, 34, etc. can be used,
Oil yellow 105, 107, Balifast yellow 1101, 1105, Balifast red 1306, Balifast blue 1603, 1607, 2610, Balifast black 18
02, 1807, 3830 (all manufactured by Orient Chemical Co., Ltd.), Aizen Spiron Yellow GRLH, 3RH, Aizen Spiron Blue GNH, 2BNH, BPNH, Aizen Spiron Black MH, GMH (above, manufactured by Hodogaya Chemical Co., Ltd.) ),
Oleosol Blue G, Oleosol Black AR (all produced by Taoka Chemical Industry Co., Ltd.), and Orasol Black RL1 (made by Ciba Geigy). As a disperse dye
CI Disperse Yellow 3, 82, 54, CI Disperse Red 60, 191 and CI Disperse Violet 57.

In the present invention, carbon black such as acetylene black, channel black and furnace black can be used, but furnace black is preferred. The carbon black that can be used has a DBP oil absorption of usually 60 to 300 ml / 100 g, preferably 90 to 200 ml / 100 g, and more preferably 9 to 200 ml / 100 g.
0 ml / 100 g or more is preferable in terms of recording density.
0 ml / 100 g or more is particularly preferred. Also 24M4D
The BP oil absorption is preferably 80 ml / 100 g or more, particularly preferably 90 ml / 100 g. The volatile matter is usually used in the range of 8% by weight or less, but 4% by weight.
Or less, and particularly preferably 3% by weight or less. Otherwise BET specific surface area is 150 meters ² / g or more storage stability, preferable from the viewpoint of ejection stability, 200 meters ² / g to 1
000 m ² / g is particularly preferred. The primary particle size is preferably 40 nm or less in terms of storage stability,
It is preferably at most 0 nm, more preferably at most 16 nm, particularly preferably at least 13 nm. Further, the pH is preferably 2 to 10, and particularly preferably 6 to 9. Here, the DBP oil absorption of carbon black is a value measured by JIS K6221A method, the volatile content is a value measured by JIS K6221 method, and the BET specific surface area is ASTM D30.
The value is a value measured by the 37D method, and the pH is determined according to JIS K622.
1, the value measured according to ASTM D3493 method, and the primary particle diameter refers to the arithmetic average diameter measured by an electron microscope.

As the above carbon black, # 2
600, # 2300, # 990, # 980, # 960, # 950, # 900, # 850,
# 750, # 650, MCF-88, MA-600, # 95, # 55, # 52, # 47
, # 45, # 45L, # 44, # 40, # 33, # 32, # 30, # 25
, # 20, # 10, # 5 (Mitsubishi Chemical), Color Black
FW1, FW2, FW2V, FW18, FW200, Special Black4,
4A, 5, 6, 100, 250, 350, 550, S160, S170,
Printex UV140U, 140V, 95, 90, 85, 80, 75, 45, 4
0, P, 60, 300, 30, 35, 25, 200, A, G, 6, L
(The above is made by Degussa), Regal415R, 330R, 1250R, 99
5R, Monarch 800, 880, 900, 460, 280, 120 (or more,
(Cabot), Raven 850, 780ULTRA, 760ULTRA, 79
0 ULTRA, 520, 500, 410, 420, 430, 450, 460,
890, 1020 (all made in Colombia) and the like. In the present invention, among the water-insoluble dyes described above, carbon black is particularly preferable.

As the water-insoluble dye used in the recording liquid of the present invention, those having the above-mentioned properties can be obtained by chemically treating the water-insoluble dye (oxidation treatment, fluorination treatment, etc.), A material in which a dispersant, a surfactant, and the like are physically or chemically bonded (grafting treatment, a material in which a dispersant is adsorbed in advance before dispersion, or the like) may be used. The aqueous medium used in the recording liquid of the present invention is mainly composed of water, but it is preferable to add a water-soluble organic solvent to water. Examples of the water-soluble organic solvent include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (# 200, # 400), glycerin, alkyl ethers of the above glycols, N-methylpyrrolidone, 1,3- Examples include dimethylimidazolinone, thiodiglycol, 2-pyrrolidone, sulfolane, dimethylsulfoxide, diethanolamine, triethanolamine, methanol, ethanol, isopropanol and the like.

In addition to the above-mentioned components, a water-soluble resin, a fungicide, a bactericide, a pH adjuster, urea and the like may be added to the recording liquid of the present invention as required. The method of preparing the recording liquid of the present invention is carried out by mixing the above-mentioned components, grinding the water-insoluble dye into fine particles using a disperser, and subjecting the fine particles to a dispersion treatment. As a dispersing machine, besides a ball mill, a roll mill, and a sand grind mill, a jet mill such as a nanomizer and an optimizer that can be pulverized without using a medium is used.In particular, a sand grind mill, or a jet with less contamination derived from the medium is used. Mills are preferred.

After this grinding and dispersion treatment, coarse particles are removed using a filter or a centrifuge. Components other than the water-insoluble pigment, dispersant and water may be added after the grinding and dispersion treatment. Further, since the grinding and dispersion treatment can be carried out efficiently by preparing the solution at a high concentration, it is preferable to finally dilute the processing solution prepared at a high concentration with an aqueous medium to adjust the concentration of the recording solution.

It is preferable that the average particle size of the water-insoluble dye in the recording liquid is in the range of 0.01 to 0.4 μm from the viewpoint of dispersion stability and ejection stability.
m is more preferred, and 0.1 to 0.3 μm is particularly preferred. Further, the maximum particle size of the water-insoluble coloring material is preferably 5 μm or less from the viewpoint of dispersion stability and ejection stability.

The SAD of the printing section specified in the present invention is 59.
To obtain five or more recorded materials, the composition of the recording liquid is not particularly limited, but can be realized by optimizing the type of the water-insoluble dye and the mixing ratio of the dispersant. The amount of the water-insoluble dye used is preferably in the range of 1 to 20% by weight based on the total weight of the recording liquid, but is preferably 3 to 15% by weight, particularly preferably 5 to 15% by weight. The amount of the dispersant used is usually in the range of 2 to 100% by weight based on the weight of the water-insoluble dye, but is preferably 3 to 50% by weight, and particularly preferably 5 to 2% by weight.
0% by weight, more preferably 5 to 15% by weight. The amount of the water-soluble organic solvent used in the recording liquid is usually 5 to 30% by weight.
But is preferably 10 to 20% by weight. The amount of the polymer used as a dispersant and / or abrasion resistance improver is preferably in the range of 0.1 to 5% by weight based on the total weight of the recording liquid, but is preferably in the range of 0.2 to 3% by weight. More preferred.

Above all, a water-insoluble dye having a DBP oil absorption of 140 ml / 100 g or more is selected, and a recording liquid containing a specific range of 5 to 15% by weight of a dispersant to carbon black is used. Thereby, the present application can be achieved more easily. More preferably, the recording liquid as described above and the primary particle diameter of carbon black is 2
It is desirable to use a carbon black having a BET specific surface area of 200 to 1000 m ² / g or a volatile matter of 4% or less. Alternatively, an excellent recording liquid can be obtained by selecting and suitably using physical properties which are preferable in the above description of carbon black.
These water-insoluble dyes, dispersants, additives, and organic solvents may be used alone, but in some cases, two or more of them may be used in combination to further enhance the effect. it can. The inkjet recording method of the present invention is to perform printing by discharging droplets of the recording liquid according to a standard method using the recording liquid thus prepared,
High quality printing can be obtained based on good ejection stability.

[0036]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which, however, are not intended to limit the scope of the invention. In the following examples, “parts” and “%” are based on weight. Example 1 (Preparation of recording liquid)

[0037]

Table 3 Composition of recording liquid Amount used (parts) Carbon black (A) 4.0 Styrene / acrylamido-2-methylpropanesulfonic acid / glycidyl-methacrylate (2,4-dihydroxybenzophenone) adduct copolymer ( Random polymer: monomer weight ratio = 30/50/20, weight average molecular weight = 6000) Na salt 0.4 1,3-dimethyl-2-imidazolidinone 4.0 ion-exchanged water 35.6．合計 Total 44.0

Each of the above components was placed in a cylindrical stainless steel container, and subjected to a dispersion treatment for 40 hours using a sand grinder together with 67 parts of glass beads having an average diameter of 0.5 mm.
The resulting solution was mixed with Olfin E1010 (Shin-Etsu Chemical sales product, acetylene glycol ethylene oxide adduct, H
LB: 13) After 0.1 part and 5 parts of ion-exchanged water were added and stirred well, 4 parts of glycerin, 3 parts of ethanol and 43.9 parts of ion-exchanged water were further added. This solution was Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid.

(Printing Test) The recording liquid obtained by the method described in the above example is filled in a washed Hewlett-Packard DeskWriter 660C black cartridge (HP51629A) and set in a printer. A black solid of 5 cm × 5 cm was prepared (100% Duty) on the above MacDraw, and inkjet recording was performed on electrophotographic paper (4024 paper manufactured by Xerox) under the following conditions.

[0040]

[Table 4] <Print conditions> Printer: DeskWriter 660C made by Hewlett-Packard Ink cartridge: HP51629A Computer: Macintosh Performa550 Software: MacDraw II 1.1 Print options: Print in monochrome Paper settings Paper size: A4, paper: plain paper option density Setting: Normal, Ink control: Automatic, Halftone: Automatic, Color preparation: Automatic Print Quality: Normal (600 × 300 dpi) As a result, it shows stable and good ejection without clogging and prints with good print quality Thing was obtained. Table 1 shows the evaluation results by the following methods.

<S. A. D. Measurement> S.I. of solid part of printed matter obtained by the above printing test A. D. Was measured under the following measurement conditions.

[0042]

[Table 5] (Measurement method) Apparatus: Scanning Probe Microscope Model: NanoScope III Scanner manufactured by Digital Instruments: J-Head Measurement area: 1 μm × 1 μm Number of pixels: 512 × 512 Scan Rate: 1.5 Hz Measurement mode: Tapping AFM search Needle: Seiko Instruments Inc. Si-DF 20 Surface image processing: Planefit Auto Tertiary

The surface of the printing portion was measured under the above conditions.
A. D. Is calculated. The measurement area is a part avoiding the fiber part of the paper, and the data is averaged at four points (four areas).

<Evaluation of Print Density> The density of the printed matter obtained in the above print test was measured using a Macbeth reflection densitometer (RD914). The results were classified as follows and are shown in Table 1 below.

[0045]

[Table 6] ・: OD 1.5 or more ・ ・ ・: OD 1.4 or more and less than 1.5 △: · OD 1.3 or more and less than 1.4 × ... · OD less than 1.3

(Water Resistance Test) The printed matter obtained in the printing test was immersed in tap water taken in a beaker for 5 seconds. After drying the printed matter,
The presence or absence of character stain was visually evaluated. The results were classified as follows and are shown in Table 1 below.

[0047]

[Table 7] ○ · · · almost no character dirt △ · · · · slightly fouled, but no practical problem × · · · severe character dirt

(Light fastness test) The printed matter was irradiated with a xenon fade meter (manufactured by Suga Test Instruments Co., Ltd.) for 100 hours to visually evaluate the discoloration and discoloration. The results were classified as follows and are shown in Table 1 below.

[0049]

[Table 8] ○ · · · Good △ · · · discoloration, but there is no practical problem × · · · severe discoloration

(Measurement of Particle Size Distribution) A particle size distribution meter (MicrotracUPA (Nikkiso sales)) of the obtained recording liquid at the same concentration
The particle size distribution was measured. <Measurement conditions>

[0051]

[Table 9] Transparent Particles: No, Spherical Part
icles: No, Particle Refractive Index: 1.81 Particle Density: 1.86 Fluid Refractive Index: 1.33 High Temp: 30.0 ℃ Viscosity: 0.797 cP Low Temp: 20.0 ℃ Viscosity: 1.002 cP Run Time: 300 (sec), Number of Runs: 2

The average of two measurements under the above measurement conditions was taken as the value of the particle size distribution of the recording liquid. as a result,
The average particle size of the recording liquid obtained in Example 1 was 0.068 μm.
Met.

(Storage stability test)
After storage at room temperature for 1 week, the temperature was returned to room temperature after storage, and the particle size distribution was measured by the same method as above using a particle size distribution meter (MicrotracUPA (Nikkiso sales)) at the same concentration. The obtained results were compared with the results of the above-mentioned particle size distribution measurement test, and a difference was measured for each fraction of the measured particle size, and the total (%) was calculated.

Example 2 (Preparation of recording liquid)

[Table 10] Composition of recording liquid Used amount (parts) Carbon black (B) 4.0 Styrene / acrylamido-2-methylpropanesulfonic acid / glycidyl methacrylate (2,4-hydroxybenzophenone) adduct copolymer (random) Polymer: monomer weight ratio = 30/50/20, weight average molecular weight = 6000) Na salt 0.4 1,3-dimethylimidazolidinone 4.0 ion-exchanged water 35.6%合計 Total 44.0

Each of the above components was placed in a cylindrical stainless steel container and subjected to a dispersion treatment for 3 hours using a sand grinder together with 152 parts of zirconia beads having an average diameter of 0.5 mm. 4 parts of glycerin, 3 parts of ethanol and 49 parts of ion-exchanged water were added to the obtained liquid, and the mixture was stirred well.
o. Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid. The average particle size of the obtained liquid is 0.180 μm.
m. Using the recording liquid obtained here, printing was performed in the same manner as in Example 1, and evaluation was performed. Table-Results
1 is shown.

Example 3 (Preparation of recording liquid)

Table 11 Composition of recording liquid Amount used (parts) Carbon black (Color Black FW18, manufactured by Degussa) 4.0 Styrene / acrylamide-2-methylpropanesulfonic acid / glycidyl methacrylate (2,4-hydroxybenzophenone) adduct Na salt of copolymer (random polymer: monomer weight ratio = 30/50/20, weight average molecular weight = 6000) 0.4 1,3-dimethyl-2-imidazolidinone 4.0 ion-exchanged water 35.6%合計 Total 44.0

Each of the above components was placed in a cylindrical stainless steel container, and subjected to a dispersion treatment for 3 hours using a sand grinder together with 152 parts of zirconia beads having an average diameter of 0.5 mm. 4 parts of glycerin, 3 parts of ethanol and 49 parts of ion-exchanged water were added to the obtained liquid, and the mixture was stirred well.
o. Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid. The average particle size of the obtained liquid is 0.103 μm.
m. Using the recording liquid obtained here, printing was performed in the same manner as in Example 1, and evaluation was performed. Table-Results
1 is shown.

Comparative Example 1 Commercially available black ink cartridge for ink jet recording (HP C4840A, manufactured by Hewlett-Packard Company)
And the same evaluation as in Example 1 was performed.
The results are shown in Table 1. Comparative Example 2 S.R. A. D. Was 7.0 when measured. From these results, S.P.S. of Examples 1 to 3 and Comparative Examples 1, 3 to 5 were evaluated. A. D. Was confirmed to be a value derived from the recording liquid.

Comparative Example 3 A commercially available black ink cartridge for ink jet recording (HP 51645A manufactured by Hewlett-Packard Company)
And the same evaluation as in Example 1 was performed.
The results are shown in Table 1. Comparative Example 4 Commercially available black ink cartridge for inkjet recording (HP 51629A manufactured by Hewlett-Packard Company)
And the same evaluation as in Example 1 was performed.
The results are shown in Table 1.

Comparative Example 5 An ink was extracted from a commercially available black ink cartridge for ink jet recording (12A1970 manufactured by Lexmark), and the same evaluation as in Example 1 was performed. The results are shown in Table 1.

[0061]

[Table 12]

In Table 1, the storability test (%) is the result of taking the difference between the particle size distributions immediately after the preparation of the recording liquid and after storage at 70 ° C. for one week, and calculating the total. Table 2 below shows the physical properties of carbon black used in Examples 1 to 3.

[0063]

[Table 13] * FC: Furnace Carbon Black CC: Channel Carbon Black

[0064]

When the recording liquid of the present invention is used, a stable recorded image having a high recording density and no printing unevenness can be obtained even when ink jet recording is performed on plain paper or recycled paper.
In addition, it is possible to obtain a recorded matter which has good storage stability and discharge stability, and also has good image fastness such as water resistance and light resistance. Since the present invention has the above characteristics, it can be used as a recording liquid for other purposes, not limited to ink jet and writing instruments.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuro Murayama 1000 Kamoshita-cho, Aoba-ku, Yokohama-shi, Kanagawa Prefecture Mitsubishi Chemical Corporation Yokohama Research Laboratory F-term (reference) 2C056 EA13 FC01 4J039 AB04 AD01 AD02 AD03 AD09 AD10 AD14 AD17 AD22 AE01 AE07 BA04 BC07 BC09 BC12 BC13 BC19 BC20 BC31 BC33 BC35 BC36 BC37 BC50 BC51 BC54 BC55 BC56 BE01 BE07 BE08 BE12 BE22 CA06 EA15 EA16 EA17 EA19 EA35 EA36 EA38 EA42 EA44 GA24

Claims (14)

[Claims] Claims 1. A. D. (Surface Area Differenc
e) is in the range of 6.0 to 9.0 and the pH is in the range of 6 to 8, the printing portion when printing at a resolution of 600 × 300 dpi and 100% duty on electrophotographic paper. S. A. D. Is 59.5 or more. 2. The printing apparatus according to claim 1, A. D. Is 60.0-9
2. The recording liquid according to claim 1, which is within a range of 0.0. 3. The recording liquid according to claim 1, wherein the density of the printing portion is OD 1.5 or more. 4. The electrophotographic paper is made of Xevox 4024.
The recording liquid according to claim 1, which is paper. 5. The recording liquid according to claim 1, wherein the recording liquid contains an aqueous medium and a water-insoluble dye. 6. The recording liquid according to claim 5, wherein the water-insoluble dye is carbon black. 7. The recording liquid according to claim 1, wherein the cumulative difference between the particle size distribution immediately after preparation of the recording liquid and the particle size distribution after storing the recording liquid at 70 ° C. for one week is 20% or less. 8. Carbon black having a DBP oil absorption of 140 ml / 100 g or more, and carbon black 10
A recording liquid comprising 5 to 15 parts by weight of a dispersant with respect to 0 parts by weight. 9. The recording liquid according to claim 8, wherein the dispersant is a polymer dispersant. 10. The carbon black has a primary particle size of 20 n.
9. The recording liquid according to claim 8, wherein m is equal to or less than m. 11. S. A. D. (Surface Area Differe
nce) is in the range of 6.0 to 9.0 and the pH is 6 to 8
Is printed on the electrophotographic paper at a resolution of 600 × 300 dpi and at 100% duty. A. D. 9. The recording liquid according to claim 8, wherein the value is 59.5 or more. 12. The recording liquid according to claim 1, wherein the cumulative difference between the particle size distribution immediately after preparation of the recording liquid and the particle size distribution after storing the recording liquid at 70 ° C. for one week is 20% or less. 13. A printed matter obtained by an ink jet recording method in which droplets of the recording liquid are ejected using the recording liquid according to claim 1. 14. An ink jet recording method for performing recording by discharging droplets of the recording liquid, wherein the recording liquid according to claim 1 is used as the recording liquid.