JP2000169776A - Aqueous magenta ink composition and ink jet recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-base ink composition having a hue wide in color developing range and clarity suitable for ink jet recording and improved in light resistance and water resistance and the like of a recorded matter by incorporating as a coloring matter component a disulfonic acid derivative (salt) of a specific compound in the ink. SOLUTION: In an aqueous medium comprising water or water and 0-30 wt.% of an organic solvent, 0.1-20 wt.%, preferably 1-10 wt.% of a disulfonic acid derivative (salt) of a compound of the formula as a coloring matter component and 0-5 wt.% of agents for preparing an ink such as an antiseptic fungicide, a pH adjusting agent, a chelating agent, an antirust agent, a water-soluble ultraviolet absorber, a water-soluble polymer compound, a dye solvent, a surfactant and the like are dissolved to give the water-base magenta ink composition having a pH of 6-11. The coloring material component is obtained by subjecting a compound of the formula to a sulfonation reaction in sulfuric acid containing 5-12 wt.%, preferably 6-10 wt.% of fuming sulfuric acid at 0-60 deg.C, preferably at 10-30 deg.C for 5 min to 20 hr, preferably for 30 min to 5 hr.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink composition and, more particularly, to an anthrapyridone compound or a salt thereof as a coloring matter component, which has a wide coloration range and is excellent in color tone, light fastness and water fastness. The present invention relates to a water-soluble magenta ink composition for inkjet recording and an inkjet recording method using the same.

[0002]

2. Description of the Related Art Various ink ejection methods have been developed as recording methods using an ink jet printer.
In each case, recording is performed by generating small ink droplets and attaching them to various recording materials (paper, film, cloth, etc.). The recording method using an ink-jet printer has rapidly spread in recent years because of the features that the recording head does not come into contact with the recording material, so that no sound is generated, and that the printer can be reduced in size, increased in speed, and easily colored. , Great growth is expected in the future. In order to record an image or character information on a color display of a computer in color by an ink jet printer, generally, four color inks of yellow (Y), magenta (M), cyan (C) and black (K) are used. Is represented by subtractive color mixing. C
In order to reproduce an additive color mixture image by R, G, B such as an RT display with a subtractive color mixture image as faithfully as possible, the dyes used, especially the dyes used in the YMC ink, are as standard as possible with the respective YMC standard (( "Japan Color" published by Japan Printing Machinery Association)
It is desired that the material has a hue close to the above and is sharp.
Further, the ink composition is required to be stable for long-term storage, to have a high density of a printed image, and to be excellent in fastness such as water fastness and light fastness. The present invention relates to magenta ink.

[0003]

The use of ink jet printers has been expanded from small printers for office automation to large printers for industrial use, and more robustness such as water fastness and light fastness is required more than ever. . Water resistance is greatly improved by coating inorganic or organic fine particles, such as cationic polymers, porous silica, alumina sol, and special ceramics, which are not inorganic fine particles, which can adsorb the dye in the ink, together with PVA resin on the paper surface. Various coated papers for improved inkjet printing are already on the market. However, in many cases, satisfactory water resistance cannot be obtained. In addition, there is no established technique for significantly improving light fastness, and in particular, YMCK 4
Of the primary colors, many magenta dyes have inherently poor lightfastness, and improvement thereof is an important issue.

A magenta dye skeleton used in a water-soluble ink for ink-jet recording is disclosed in JP-A-54-89811.
Xanthene series found in JP-A-8-60053 and JP-A-8-143798, and JP-A-61-62562, JP-A-62-156168, JP-A-3-20397
Azo series using H acid, which are found in Japanese Patent Application Laid-Open No. Hei 7-57698 and Japanese Patent Publication No. 7-78190, are typical. However, xanthene-based resins have very good hue and sharpness but very poor light fastness. In addition, some azo compounds using H acid have good hue and water resistance, but have poor light resistance and sharpness. As described in JP-A-3-203970, magenta dyes having excellent clarity and light resistance have been developed for this type, but light-fastness is higher than dyes of other hues such as cyan dyes and yellow dyes represented by copper phthalocyanine. Is still inferior.

Further, as a dye skeleton of magenta having excellent sharpness and light resistance, for example, JP-A-57-195775, JP-A-5-195775
Anthrapyridone compounds found in 9-74173 and JP-A No. 2-16171 are known, but satisfy all of the wide color appearance range, hue, sharpness, light resistance, water resistance and dissolution stability Nothing to do has been obtained. An object of the present invention is to provide a magenta aqueous ink composition having a wide hue and sharpness in a color development range suitable for inkjet recording, and having high fastness such as light fastness and water fastness of a recorded matter. .

[0006]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have accomplished the present invention. That is, the present invention provides (1) a dye component represented by formula (2):

[0007]

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An aqueous magenta ink composition comprising a disulfonic acid form of the compound represented by the formula (1) or a salt thereof, and (2) a dye component, represented by the formula (2) described in (1): The content of the disulfonic acid form of the compound is 85% or more (area ratio by high performance liquid chromatography (HPLC)), and the content of the monosulfonic acid form of the compound represented by the formula (2) described in (1). Is not more than 10% (area ratio by HPLC), the aqueous magenta ink composition according to (1), (3) a disulfonic acid compound represented by formula (1):

[0009]

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The aqueous magenta ink composition according to (1) or (2), which is a compound represented by the following formula (or a salt thereof, the same applies hereinafter): (4) Water (1) to (3) containing an organic solvent The aqueous magenta ink composition according to any one of (1) to (4), wherein the content of the inorganic salt is 1% by weight or less. (6) The aqueous magenta ink composition according to any one of (1) to (5), which is for inkjet recording, and (7) ink droplets are ejected in accordance with a recording signal to record on a recording material. In the inkjet recording method to be performed, the aqueous magenta ink composition according to any one of (1) to (5) is used as an ink, and (8) an ink droplet is formed according to a recording signal. Ejected An ink jet recording method for performing recording on a recording material by using the aqueous magenta ink composition according to any one of claims 1 to 5 as a magenta ink and an aqueous solution containing a water-soluble metal phthalocyanine dye as a cyan ink. An inkjet recording method characterized by using a cyan ink,

(9) The ink jet recording method according to (8), wherein the recording material is a fiber material containing a polyamide group, and the fiber material is subjected to a heat treatment after the application of the ink composition. 10) The inkjet recording method according to (8), wherein the recording material is an information transmission sheet.
(11) The inkjet recording method according to (10), wherein the information transmission sheet is a surface-treated sheet, (12).
(1) An ink jet printer having the container containing the aqueous magenta ink composition according to any one of (5) and the container containing the aqueous cyan ink composition containing a water-soluble metal phthalocyanine dye.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The aqueous magenta ink composition of the present invention is characterized by containing a disulfonic acid form of the compound represented by the formula (2) or a salt thereof as a coloring matter component.
The content of the disulfonic acid form of the compound represented by the formula (2) in the dye component is determined by HPLC (hereinafter, measured under the following conditions. Column; Inertsil ODS-2 (6.0 I, D, 1
50mm), Mobile Phase (mobile phase); CH ₃ CN / 0.05wt% NH ₄
H ₂ PO ₄ = 40/60 (w / w), Flow Rate (flow rate); 0.8 ml / mi
n. , Col. Temp. (Temperature): 40 ° C., Area ratio by Detector (UV-254 nm) is 85% or more, preferably 90% or more, more preferably 92% or more, particularly preferably 95% or more. The disulfonic acid form of the compound represented by the formula (2) is specifically represented by, for example, the formula (1).

Since the dye component used in the present invention is obtained by sulfonating the compound represented by the formula (2), a monosulfonic acid compound is mixed in addition to the disulfonic acid compound during the production process. However, from the viewpoints of easiness in ink production (for example, liquid filterability), stability over time of ink, and clarity of recorded matter, it is preferable that the content of the monosulfonic acid compound is small, For example, the monosulfonic acid form is about 10% or less (including 0%), preferably about 5% or less, more preferably about 2% or less, particularly preferably about 1% or less in terms of area ratio by HPLC. Needless to say, it is better not to contain the compound of the formula (2) in the ink composition of the present invention.

The dye component used in the present invention is, for example, the compound of the formula (2) (the compound of the formula (2) is described in USP 2,644,82).
1. ) In a sulfuric acid containing fuming sulfuric acid. The concentration of fuming sulfuric acid in sulfuric acid is 5 to 12% by weight, preferably 6 to 12%.
10% by weight. The reaction temperature is generally 0-60 ° C, preferably 10-30 ° C. The reaction time varies depending on the reaction temperature, but is usually 5 minutes to 20 hours, and in a preferred embodiment, 30 minutes to 5 hours. This sulfonation is performed by HPLC
The end point is defined as the time when the compound of the formula (2) disappears and the monosulfonic acid compound becomes 10% or less, preferably 5% or less, more preferably 2% or less, particularly preferably 1% or less in the area ratio according to I do. After completion of the reaction, the reaction solution is poured into ice water, salted out, filtered and dried to obtain the compound of the formula (1).

The compound thus obtained is in the form of the free acid,
Or it exists in the form of its salt. In the present invention, it can be used as an alkali metal salt, alkaline earth metal salt, alkylamine salt, alkanolamine salt or ammonium salt. Preferred salts are sodium salts, potassium salts, alkali metal salts such as lithium salts, monoethanolamine salts, diethanolamine salts, triethanolamine salts,
Alkanolamine salts such as monoisopropanolamine salt, diisopropanolamine salt, and triisopropanolamine salt are exemplified.

The aqueous ink composition of the present invention is obtained by dissolving the above-mentioned dye component in water or an aqueous solvent (water containing an organic solvent described later). The pH of the ink is preferably about 6 to 11. When using this aqueous ink composition in an ink jet recording printer, it is preferable to use a small amount of inorganic substances such as chlorides and sulfates of metal cations as pigment components. The total content of sodium chloride and sodium sulfate is 1% by weight or less in the aqueous ink composition. In order to produce the coloring matter component of the present invention containing few inorganic substances, for example, a conventional method using a reverse osmosis membrane or a dried product or a wet cake of the coloring matter component of the present invention is stirred in a mixed solvent of methanol and water, filtered and dried. Desalination may be performed by a method.

The aqueous ink composition of the present invention is prepared using water as a medium, and the pigment component is contained in the aqueous ink composition.
Preferably 0.1-20% by weight, more preferably 1-1.
0% by weight, more preferably about 2 to 8% by weight. The aqueous ink composition of the present invention may further contain 0 to 30% by weight of a water-soluble organic solvent and 0 to 5% by weight of an ink preparation.

Examples of the water-soluble organic solvent include C 1 -C 4 alcohols such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol and tert-butanol, N, N-dimethylformamide and N, N-dimethyl. Carboxylic acid amides such as acetamide, lactams such as ε-caprolactam, N-methylpyrrolidin-2-one, urea, 1,3-dimethylimidazolidin-2-one or 1,3-dimethylhexahydropyrimid-2-one Cyclic urea such as on, acetone,
Ketone or keto alcohol such as methyl ethyl ketone, 2-methyl-2-hydroxypentan-4-one, ether such as tetrahydrofuran, dioxane, ethylene glycol, 1,2- or 1,3-propylene glycol,
Mono- having C2-C6 alkylene units such as 1,2- or 1,4-butylene glycol, 1,6-hexylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, thiodiglycol, polyethylene glycol, polypropylene glycol, etc. ,
Oligo- or polyalkylene glycol or thioglycol, polyol (triol) such as glycerin, hexane-1,2,6-triol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene Examples thereof include C1 -C4 alkyl ethers of polyhydric alcohols such as glycol monomethyl ether and triethylene glycol monoethyl ether, γ-butyrolactone, and dimethyl sulfoxide.

These organic solvents may be used in combination of two or more. Among these organic solvents, preferred are:
For example, water and N-methylpyrrolidin-2-one, C2 -C
Mono-, di- or trialkylene glycols having 6 alkylene units (preferably mono-, di- or triethylene glycol, dipropylene glycol), dimethyl sulfoxide, etc., and especially N-methylpyrrolidine-2-
The use of on, diethylene glycol, dimethyl sulfoxide is preferred.

Examples of the ink preparation agent include an antiseptic / antifungal agent, a pH adjuster, a chelating agent, a rust inhibitor, a water-soluble ultraviolet absorber, a water-soluble polymer compound, a dye dissolving agent, a surfactant and the like. Examples of the antiseptic / antifungal agent include sodium dehydroacetate, sodium sorbate, sodium 2-pyridinethiol-1-oxide, sodium benzoate, sodium pentachlorophenol and the like. pH
As the adjusting agent, any substance can be used as long as it can control the pH of the ink in the range of 6 to 11 without adversely affecting the ink to be prepared. Examples thereof include alkanolamines such as diethanolamine and triethanolamine, hydroxides of alkali metal elements such as lithium hydroxide, sodium hydroxide, and potassium hydroxide, ammonium hydroxide, and lithium carbonate, sodium carbonate, and potassium carbonate. Examples thereof include carbonates of alkali metals. Examples of the chelating reagent include sodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxytylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate, and sodium uramildiacetate. As a rust inhibitor,
For example, acid sulfite, sodium thiosulfate, ammonium thioglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, dicyclohexylammonium nitrite and the like can be mentioned.

The ink composition of the present invention is prepared by adding and mixing the above-mentioned dye and, if necessary, the above-mentioned water-soluble organic solvent, ink preparation agent and the like to water containing no impurities such as distilled water. Further, the dye may be added to and dissolved in a mixture of water and the above-mentioned water-soluble organic solvent, ink preparation agent and the like.
If necessary, filtration may be performed after obtaining the ink composition to remove impurities.

As a recording material of the ink jet recording method of the present invention, for example, a sheet for transmitting information such as paper and film,
Fiber and leather. As the information transmission sheet, those subjected to a surface treatment, specifically, those provided with an ink receiving layer on these substrates are preferable. The ink-receiving layer is formed, for example, by impregnating or coating the above-described base material with a cationic polymer, or by disposing inorganic fine particles capable of absorbing a dye in the ink, such as porous silica, alumina sol or special ceramics, to polyvinyl alcohol or polyvinyl pyrrolidone. It is provided by coating on the surface of the base material together with the hydrophilic polymer. Those provided with such an ink receiving layer are usually called paper (film) for exclusive use of ink jet, glossy paper (film) or the like, and include, for example, Pictorico (manufactured by Asahi Glass Co., Ltd.), color BJ paper, color BJ photo film sheet Is also commercially available as Canon Inc.), color image jet paper (manufactured by Sharp Corporation), glossy film for Super Fine (manufactured by Epson Corporation), Pictafine (manufactured by Hitachi Maxell), and the like. Of course, it can be used for plain paper.

The fibers are preferably polyamide fibers such as nylon, silk and wool, and nonwoven fabrics and cloths are preferred. For these fibers, after applying the ink composition of the present invention to the fibers, preferably after applying the ink composition by an ink jet recording method, the wet heat (for example, about 80 to 1) is applied.
By adding a fixing step of 20 ° C.) or dry heat (for example, about 150 ° C. to 180 ° C.), a dye can be dyed on the fiber to obtain a dyed article having excellent clarity, light fastness and washing resistance. Can be.

In order to record on a recording material by the ink jet recording method of the present invention, for example, a container containing the above-described aqueous magenta ink composition is set in an ink jet printer, and recording is performed on the recording material by an ordinary method. I just need. Examples of the ink jet printer include a piezo printer using mechanical vibration and a bubble jet printer using bubbles generated by heating.

In the ink jet recording method of the present invention, the above aqueous magenta ink composition is used in combination with a yellow ink composition, a cyan ink composition and, if necessary, a black ink composition. When using an aqueous cyan ink composition containing a water-soluble metal phthalocyanine dye as the cyan ink composition, by using the aqueous magenta ink composition in combination with the above-mentioned aqueous magenta ink composition, the color tone in the light fastness test after the color mixing of both can be obtained. Less change. As the metal in the water-soluble metal phthalocyanine dye, for example, copper, nickel,
Aluminum and the like can be mentioned, and copper is preferable. Examples of the water-soluble copper phthalocyanine dye include C.I. I. Direct Blue 86, C.I. I. Direct Blue 87,
C. I. Direct Blue 199, C.I. I. Acid Blue 249, C.I. I. Reactive Blue 7,
C. I. Reactive Blue 15, C.I. I. Reactive Blue 21, C.I. I. Reactive Blue 71
And the like.

An aqueous cyan ink composition containing a water-soluble metal phthalocyanine dye is produced, for example, according to the above-mentioned method for producing an aqueous magenta ink composition, poured into a container, and the container is charged with the aqueous magenta ink composition. Is set at a predetermined position of an ink jet printer and used similarly to the container containing.

The water-based ink composition of the present invention is a magenta color which is clear, has a color tone specified by the above-mentioned Japan color, has high saturation, has a moderate bluish color, and is close to ideal. By using with ink, color tone of wide visible range can be obtained, and when used with existing yellow, cyan, and black, which have excellent light and water resistance, recorded matter with excellent light and water resistance can be obtained. Obtainable.

[0028]

The present invention will be described in more detail with reference to the following examples. In the text, “parts” and “%” are based on weight unless otherwise specified.

Synthesis Example 1 63.7 parts of 96% sulfuric acid was charged into a reactor, and cooled to 15 to
At 20 ° C., 67.9 parts of 32.7% fuming sulfuric acid was added to obtain 7.9.
% Fuming sulfuric acid is prepared. Subsequently, 20.4 parts of the compound of the above formula (2) is added at 20 ° C. or lower under ice cooling.
The sulfonation reaction is performed at a temperature of 25 ° C. for 3 hours. Ice water 30
The above reaction solution is added to 0 parts, 20 parts of sodium chloride is added with stirring, and the mixture is stirred for 1 hour, filtered and washed with 30 parts of a 10% aqueous sodium chloride solution to obtain a wet cake. Next, the obtained wet cake is stirred with 300 parts of water for 30 minutes, and then filtered to remove a small amount of insoluble matter. 25 parts of sodium chloride is added to the mother liquor under stirring to carry out salting out. After stirring for 1 hour, the mixture is filtered and dried to obtain the pigment component used in the present invention as a reddish powder. This is used as a wet cake and 2.3
The mixture was stirred in methanol twice as much at room temperature for 1 hour, filtered, washed with methanol and dried to obtain 24.3 parts (λmax: 529 nm (in an aqueous solution)) of the compound of the above formula (1) containing very few inorganic salts. Is obtained as

Example 1 (1) Preparation of Ink Composition A liquid having the composition shown in the following Table 1 was prepared and filtered with a 0.45 μm membrane filter (manufactured by Toyo Filter Paper Co., Ltd.) to obtain an aqueous ink for ink jet. Obtain the composition. This ink composition did not precipitate crystals even after 6 months,
It has good storage stability.

[0031]

(Note) Monosulfonic acid content 0.5% or less (HP
The total content of sodium chloride and sodium sulfate is 1% by weight or less. The solubility in pure water (ion-exchanged water) is about 100 g / L (2
5 ℃)

(2) Inkjet printing Inkjet printer (trade name: ENCAD NO.
VAJET III), ink jet recording was performed on a commercially available coated paper (coated paper for color image jet STX73A4 (manufactured by Sharp Corporation)). (3) Hue and clarity of the recorded image: COMEKEK recording paper
-V colorimetry using a colorimetry system (Nippon Kayaku Co., Ltd.)
^* , A ^* , and b ^* values were calculated. Hue is compared with the standard magenta color sample of JAPAN Color of Japan Printing Machinery Association (JNC). C ^* = ((a ^* ) ²
+ (B ^* ) ² ) ^1/2 .

(4) Light resistance test of recorded image Carbon arc fade meter (Suga Test Machine Co., Ltd.)
The recording paper was irradiated with carbon arc for 20 hours. The change before and after irradiation was determined according to the JIS blue scale, and the color difference before and after irradiation was measured using the above colorimetric system. (5) Water resistance test of recorded image Put recording paper in a beaker filled with water, stir for 2 minutes, take out and air dry, judge the change before and after the test by JIS discoloration gray scale, and use the above colorimetric system. The color difference was measured before and after the test.

Table 2 shows the results of the hue, sharpness, light fastness and water fastness test results of the recorded image of the aqueous magenta ink composition of the present invention prepared in Example 1.

(Table 2) Table 2 Hue Sharpness Lightfastness Waterfastness L * a * b * (C *) Judgment value (ΔE) Judgment value (ΔE) JNC standard magenta 46.3 74.4 -4.4 74.5 Ink composition of Example 1 Object 47.7 73.1 -11.4 74.0 Grade 4 (8.3) Grade 4 (10.2)

According to Table 2, the ink composition of Example 1 was
Hue and sharpness are very close to standard magenta,
In addition, the color difference before and after each test is small in light fastness and water fastness of the coated paper, and it can be said that it is very excellent. Also,
The dye component used in Examples has a water solubility of 10%.
0 g / L, which is very excellent as a dye for inkjet, enables the production of a high-concentration ink composition.

Example 2 (1) Preparation of Ink Composition In the ink of Example 1, 3.8 was added to the compound of the formula (1).
Magenta ink composition was prepared in the same manner as in Example 1 except that the amount of water and the amount of water were changed to 76.2 parts. As Comparative Example 1, a dye described in JP-A-57-195775 (M-2; CI (Color Inde
x) A magenta ink for comparison was prepared by using Acid Red 82) so as to adjust the optical density to the above-mentioned ink composition. (2) Inkjet printing In order to measure the color development range, the magenta ink composition uses the ink composition of the above (1), and the yellow ink and the cyan ink use the inks attached to the printer. Co., Ltd., trade name BJF-
600) on a commercially available coated paper (coated paper for color image jet STX73A4 (manufactured by Sharp Corporation)) in single color and mixed colors (red and blue). For reference, printing was also performed for yellow, cyan, and their compound colors (green). (3) Colorimetry a ^* , b ^* , and C ^* values were calculated according to the method described in Example 1 (3). The results are shown in Table 3 and FIG.

[0039]

According to Table 3, the magenta used in the present invention is b
^{* The} value is -5.6, which is 1 in the negative direction from the magenta of Comparative Example 1.
6.9, which indicates that the color is a magenta color having an appropriate bluish color and close to ideal. In addition, the b ^* value of blue, which is a compound color with cyan, is -52.5, which is more blue. When the a ^* b ^* values in Table 3 are plotted on the chromaticity diagram, the magenta of the present invention has a larger a ^* value than the magenta of Comparative Example 1 and a larger b ^* value in the-region, and the magenta has It can be seen that the hue of this portion can be expressed more. Also, looking at the C ^* value as an index of sharpness, the value of magenta used in the present invention is higher, indicating that the sharpness is higher. From this result, Example 2
When the ink composition of (1) is used, the sharpness is higher and the color development range is clearly wider, particularly B (blue),
It is shown that M (magenta) is superior. In addition, when the light resistance test and the water resistance test were performed on Comparative Example 1 in the same manner as in Example 1, the light resistance was grade 4,
The water resistance was grade 3 and was inferior in water resistance to magenta used in the present invention.

Example 3 (1) Preparation of ink composition An ink composition was prepared according to Example 1, except that the following magenta dye was used. Magenta dye M1: Magenta dye used in the present invention M2: Commercially available ink for inkjet printer (containing azo dye) Cyan dye C1: C.I. I. Direct Blue 86 (copper phthalocyanine dye) C2: C.I. I. Direct Blue 199 (copper phthalocyanine dye) C3: C.I. I. Reactive Blue 71 (copper phthalocyanine dye)

(2) Inkjet printing The printing was carried out according to the first embodiment. That is, using an inkjet printer (trade name: ENVA NOVAJET III), commercially available plain paper (manufactured by Canon Inc., PBPA)
PER) and a glossy paper having a dye receiving layer (Canon Inc.)
Color BJ photosheet film (CA-10
In 1)), magenta ink alone or cyan ink and magenta ink were overprinted, and inkjet recording was performed.

(3) Light Resistance Test of Recorded Image The recording paper printed in (2) was subjected to a light resistance test for 48 hours by using an accelerated xenon light resistance tester manufactured by Wacom. (4) Colorimetry The hue of the recorded image before and after the light fastness test is measured using a colorimeter (GRETAG).
(SPM50: manufactured by GRETAG) to determine the color difference (ΔE). The results are shown in Table 4.

(Table 4) Table 4 No. Plain paper Glossy paper Remarks 1-1 11.9.6 M1 alone 1-2 6.17 Overprinting of M1 and C1 1-3 3.0 5.8 Overprinting of M1 and C2 1-4 6 6.6 6.9 Overstrike of M1 and C3 2-1 11.1 13.5 M2 alone 2-2 12.6 17.8 Overstrike of M2 and C1 2-3 11.3 15.3 M2 Overstrike with C2 2-4 10.2 23.5 Overstrike with M2 and C3

In Table 4, No. Nos. 1-1 to 1-4 are samples of the present invention. 2-1 to 2-4 are control samples. No. 1-1 and No. 1 Comparing 2-1, the color difference (ΔE) between the two before and after the light resistance test is almost the same on plain paper. However, in the case of glossy paper, the color difference of the control sample is larger than that of plain paper, while the color difference of the sample of the present invention is smaller than that of plain paper. These facts indicate that the present sample and the control sample have the same level of light fastness on plain paper, and that the control sample on glossy paper has lower light fastness than plain paper. Means that the light fastness is improved.

Further, comparing the results of the combined use of the magenta dye alone and the copper phthalocyanine cyan dye, the control sample (No. 2-1 compared with 2-2 to 2-4) showed that the magenta dye alone was used on plain paper. And the color difference is about the same or expanding,
Also, the glossiness of the glossy paper is significantly larger than that of the glossy paper alone. On the other hand, in the sample of the present invention (No. 1-1 vs. 1-2 to 1-4), the color difference is significantly smaller than that of the plain paper and the glossy paper alone. These facts indicate that, when used in combination with a metal phthalocyanine cyan dye, the control sample has the same or lower light fastness, whereas the sample of the present invention has improved light fastness.

[0047]

As described above, the anthrapyridone compound used in the present invention has a very good solubility in water and a good filtering property for a filter material such as a membrane filter in the ink composition manufacturing process. Further, this anthrapyridone compound has high safety for living bodies. Furthermore, the ink composition of the present invention using this anthrapyridone compound has good storage stability without crystal precipitation, change in physical properties (change in viscosity or surface tension, etc. with time), color change, etc. after long-term storage. is there. Printed matter using the ink composition of the present invention as a magenta ink for inkjet recording is excellent in light resistance and water resistance, and when used together with yellow, cyan and black dyes, ink jet recording excellent in light resistance and water resistance is possible. The effect is remarkable for information recording paper, especially information recording paper having an ink receiving layer. In addition, the light fastness is improved by the combined use with a metal phthalocyanine cyan dye. Further, the printing surface is a clear and almost ideal magenta color, and by using it together with other yellow and cyan inks, a color tone in a wide visible region can be obtained.
Therefore, the ink composition of the present invention is very useful for a magenta ink for inkjet recording.

[Brief description of the drawings]

FIG. 1 is a diagram showing a coloring range of a dye.

[Explanation of symbols]

In FIG. 1, the X-axis represents the a ^* value in the L ^* a ^* b ^* color system, and the Y-axis also represents the b ^* value. Y indicates yellow, R indicates red, M indicates magenta, B indicates blue, C indicates cyan, and G indicates green. The solid line is the coloration range of the dyed product of Example 2, and the broken line is the coloration range of the dyed product of Comparative Example 1.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09B 67/44 C07D 221/18 // C07D 221/18 B41J 3/04 101Y F-term (Reference) 2C056 EA13 FC02 2H086 BA05 BA19 BA53 BA55 BA59 BA62 4C034 CJ07 4J039 BC06 BC39 BC55 BC60 BC61 BC69 BC74 BC77 BC79 BE02 BE12 CA03 CA06 EA15 EA35 EA38 EA44 FA02 GA24

Claims (12)

[Claims] 1. A dye component represented by the formula (2): An aqueous magenta ink composition comprising a disulfonic acid form of the compound represented by the formula (1) or a salt thereof. 2. The formula (2) according to claim 1, in a dye component.
The content of the disulfonic acid form of the compound represented by the formula is 85% or more (area ratio by HPLC), and the content of the monosulfonic acid form of the compound represented by the formula (2) according to claim 1 is 10%. % Or less (area ratio by HPLC). 3. A disulfonic acid compound represented by the formula (1): The aqueous magenta ink composition according to claim 1 or 2, which is a compound represented by the formula: or a salt thereof. 4. The aqueous magenta ink composition according to claim 1, comprising water and an organic solvent. 5. The aqueous magenta ink composition according to claim 1, wherein the content of the inorganic salt is 1% by weight or less. 6. The aqueous magenta ink composition according to claim 1, which is used for ink jet recording. 7. An ink jet recording method for recording on a recording material by discharging ink droplets according to a recording signal,
An ink-jet recording method using the aqueous magenta ink composition according to claim 1 as an ink. 8. An ink jet recording method for recording on a recording material by discharging ink droplets according to a recording signal,
6. An ink-jet method comprising using the aqueous magenta ink composition according to any one of claims 1 to 5 as a magenta ink, and using an aqueous cyan ink composition containing a water-soluble metal phthalocyanine dye as a cyan ink. Recording method. 9. The ink jet recording method according to claim 8, wherein the recording material is a polyamide fiber material, and the fiber material is subjected to a heat treatment after the application of the ink composition. 10. The ink jet recording method according to claim 8, wherein the recording material is an information transmission sheet. 11. The ink jet recording method according to claim 10, wherein the information transmission sheet is a surface-treated sheet. 12. An ink jet printer having a container containing the aqueous magenta ink composition according to any one of claims 1 to 5 and a container containing an aqueous cyan ink composition containing a water-soluble metal phthalocyanine dye.