WO2014132926A1

WO2014132926A1 - Azo compound, ink composition, recording method, and pigment body

Info

Publication number: WO2014132926A1
Application number: PCT/JP2014/054348
Authority: WO
Inventors: 靖章石黒; 安里小野寺
Original assignee: 日本化薬株式会社
Priority date: 2013-03-01
Filing date: 2014-02-24
Publication date: 2014-09-04
Also published as: TW201437291A; JPWO2014132926A1

Abstract

The purpose of the present invention is to provide an azo compound represented by formula (1), a tautometer thereof, or a salt of either of these, as a pigment that, when recoding on special paper for inkjet use, has extremely outstanding anti-bronzing properties and moisture resistance, extraordinarily high printing density, outstanding color rendering properties, low color saturation, a high-grade black color phase, and outstanding colorfastness of various kinds, including (ozone) gas resistance and the like. Moreover, another purpose of the present invention is to provide an ink composition containing such a pigment, particularly a black ink composition for inkjet recording. In the formula, R¹ represents a (C1-C4) alkyl group or the like, R² represents a cyano group, R³ and R⁴ each independently represent a hydrogen atom, a sulfo group, or the like, R⁵ and R⁷ each independently represent a (C1-C4) alkylthio group, R⁶ and R⁸ each independently represent a (C1-C4) alkylcarbonylamino group, R⁹ represents a sulfo (C1-C4) alkoxy group, R¹⁰ represents a methyl group or the like, and R¹¹-R¹³ each independently represent a hydrogen atom, a sulfo group, or the like.

Description

Azo compound, ink composition, recording method and colored body

The present invention relates to a novel azo compound or a tautomer thereof, or a salt thereof, an ink composition containing these, and a colored body colored by them.

A recording method using an ink jet printer, that is, an ink jet recording method is one of representative methods among various color recording methods. The ink jet recording method performs recording by generating droplets of ink and attaching them to various recording materials (paper, film, fabric, etc.). This method is quiet because it does not generate sound because the recording head and the recording material are not in direct contact. Moreover, since it has the feature that it is easy to reduce the size and increase the speed, it has been spreading rapidly in recent years, and is expected to grow greatly in the future.
Conventionally, water-based inks in which water-soluble pigments are dissolved in an aqueous medium have been used as fountain pens, felt-tip pens, and inks for ink jet recording. In general, a water-soluble organic solvent is added to these water-based inks in order to prevent clogging of the ink at the pen tip or the ink discharge nozzle. These inks provide a recorded image with sufficient density, do not cause clogging of the pen tip and nozzles, have good drying properties on recording materials, have little bleeding, and have storage stability. It is required to be excellent. Further, the water-soluble dye used is required to have particularly high solubility in water and high solubility in the water-soluble organic solvent added to the ink. Further, the formed image is required to have image fastness such as water resistance, light resistance, gas resistance and moisture resistance.

Among these, the gas resistance refers to the resistance to a phenomenon in which ozone gas having an oxidizing action existing in the air acts on the dye on the recording material or in the recording material to cause the recorded image to discolor. That is. In addition to ozone gas, examples of the oxidizing gas having this kind of action include NOx and SOx. However, among these oxidizing gases, ozone gas is regarded as a main causative substance that promotes the discoloration phenomenon of ink jet recorded images, and particularly, ozone gas resistance is regarded as important. An ink receiving layer is provided on the surface of the dedicated inkjet paper on which photographic image quality can be obtained in order to speed up drying of the ink and reduce bleeding at high image quality. In many cases, the ink receiving layer is made of a material such as a porous white inorganic material. On such a recording paper, the discoloration due to ozone gas or the like is noticeable. Since this discoloration phenomenon due to the oxidizing gas is characteristic of an ink jet recording image, improvement of gas resistance, particularly ozone gas resistance, is one of the most important issues in ink jet recording.

Also, the bronzing phenomenon may be a problem. The bronzing phenomenon is a phenomenon in which the dye is formed on a metal piece on the surface of the recording material and is glaring due to the association of the dye and the ink absorption failure. When this phenomenon occurs, the gloss, print quality, and print density are all inferior. Especially when a metal phthalocyanine dye is used as a pigment, it often appears as a “red float phenomenon” in the portion printed at a high density, and the balance of the entire image becomes non-uniform and the quality is deteriorated. A pigment that does not cause a phenomenon is desired. In recent years, glossy paper is often used as a recording medium having a texture similar to a photographic tone. However, when the bronzing phenomenon occurs, the glossiness on the surface of the recorded material varies, and the texture of the image is significantly impaired. From this viewpoint, there is a strong demand for a dye that does not cause a bronzing phenomenon. In the present specification, a dye that does not cause the bronzing phenomenon is described as a dye having excellent bronzing resistance.

In the future, in order to expand the field of use of inkjet recording, inkjet recording images are strongly required to be further improved in light resistance, gas resistance, moisture resistance, water resistance, bronzing resistance and the like. In addition to this, a black image is required to have excellent color rendering properties. A phenomenon in which the hue appears to change depending on the type of the light source is referred to as color rendering, but generally this phenomenon is likely to occur in black dyed matter or recorded matter. In the field of dyeing processing, it is common to use a compound having absorption at a long wavelength as a method for improving color rendering properties. For example, Patent Document 6 and Non-Patent Document 1 disclose these methods.

Ink of various hues is prepared from various pigments, and among them, black ink is an important ink used for both monocolor and full-color images. Many pigments for these black inks have been proposed to date, but they have not yet provided a pigment that sufficiently satisfies the market demand. Many of the proposed dyes are azo dyes, of which C.I. I. Disazo dyes such as Food Black 2 have problems such as poor water resistance and moisture resistance, insufficient light resistance and gas resistance, and high color rendering. A polyazo dye having an extended conjugated system generally has problems such as low water solubility, easily causing a bronzing phenomenon in which a recorded image has a partially metallic luster, and insufficient light resistance and gas resistance. Similarly, many azo metal-containing dyes that have been proposed have good light resistance, but they contain metal ions, which are undesirable for biological safety and environmental problems, and have extremely low gas resistance. There are problems such as.

As a black compound (black pigment) for ink jet recording which has been improved with respect to gas resistance, which has become the most important issue in recent years, for example, compounds described in Patent Document 1 can be mentioned. Although the gas resistance of these compounds has been improved, they do not fully meet market demands. Further, azo compounds having a benzimidazolopyridone skeleton, which is one of the characteristics of the black pigment of the present invention, are disclosed in Patent Documents 3 to 5 and the like. Patent Documents 3 and 4 disclose that a trisazo compound and a water-soluble black compound are used for inkjet recording. Patent Documents 5 and 8 disclose that a tetrakisazo compound and a water-soluble black compound are used for inkjet recording.

International Publication No. 2005/054374 International Publication No. 2004/050768 International Publication No. 2007/077931 International Publication No. 2009/069279 JP 2008-169374 A Japanese Unexamined Patent Publication No. 01-284562 JP 2004-75719 A International Publication No. 2012/081640

The present invention is particularly excellent in bronzing resistance and moisture resistance when recorded on ink jet dedicated paper, and also has excellent (ozone) gas resistance, light resistance, and moisture resistance, extremely high print density, and excellent color rendering. Another object of the present invention is to provide a dye having a low chroma and a high-quality black hue, and an ink composition containing the dye, particularly a black ink composition for inkjet recording.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a specific azo compound can solve the above-mentioned problems, and have completed the present invention.

That is, the present invention
1)
An azo compound represented by the following formula (1) or a tautomer thereof, or a salt thereof;

[In Formula (1),
R ¹ represents a (C1-C4) alkyl group; or a (C1-C4) alkyl group substituted with a carboxy group;
R ² represents a cyano group;
R ³ and R ⁴ each independently represent a hydrogen atom; a (C1-C4) alkoxy group; or a sulfo group;
R ⁵ represents a (C1-C4) alkylthio group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group;
R ⁶ represents a (C1-C4) alkylcarbonylamino group;
R ⁷ represents a (C1-C4) alkylthio group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group;
R ⁸ represents a (C1-C4) alkylcarbonylamino group;
R ⁹ represents a sulfo (C1-C4) alkoxy group;
R ¹⁰ represents a methyl group; or a halogen atom;
R ¹¹ to R ^{13 each} represents a hydrogen atom; a sulfo group; or a halogen atom.
However, when R ¹⁰ is a methyl group, one of R ¹¹ to R ¹³ is a hydrogen atom, the other two are sulfo groups, and when R ¹⁰ is a halogen atom, 1 of R ¹¹ to R ¹³ is 1 One is a hydrogen atom, one is a halogen atom, and the other is a sulfo group. ]

2)
The azo compound represented by the above formula (1) is represented by the following formula (2), the azo compound according to the above 1) or a tautomer thereof, or a salt thereof,

[In formula (2), R ¹ to R ¹³ represent the same meaning as in formula (1) above. ]

3)
R ¹ is a methyl group;
R ² is a cyano group;
R ³ is a methoxy group;
R ⁴ is a sulfo group;
R ⁵ is a sulfo (C1-C4) alkylthio group;
R ⁶ is a (C1-C4) alkylcarbonylamino group;
R ⁷ is a sulfo (C1-C4) alkylthio group;
R ⁸ is a (C1-C4) alkylcarbonylamino group;
R ⁹ is a sulfo (C1-C4) alkoxy group;
R ¹⁰ is a methyl group;
R ¹¹ is a hydrogen atom;
R ¹² is a sulfo group;
R ¹³ is a sulfo group; the azo compound according to 1) or 2) or a tautomer thereof, or a salt thereof,

4)
R ¹ is a methyl group;
R ² is a cyano group;
R ³ is a methoxy group;
R ⁴ is a sulfo group;
R ⁵ is a sulfo (C1-C4) alkylthio group;
R ⁶ is a (C1-C4) alkylcarbonylamino group;
R ⁷ is a sulfo (C1-C4) alkylthio group;
R ⁸ is a (C1-C4) alkylcarbonylamino group;
R ⁹ is a sulfo (C1-C4) alkoxy group;
R ¹⁰ is a chlorine atom;
R ¹¹ is a hydrogen atom;
R ¹² is a chlorine atom;
R ¹³ is a sulfo group; the azo compound according to 1) or 2) or a tautomer thereof, or a salt thereof,

5)
An aqueous ink composition containing at least one kind of the azo compound according to any one of 1) to 4) or a tautomer thereof, or a salt thereof;
6)
The water-based ink composition as described in 5) above, further comprising a water-soluble organic solvent,
7)
An ink jet recording method for recording on a recording material by using the water-based ink composition according to 5) or 6) as an ink, and discharging ink droplets of the ink according to a recording signal;
8)
The inkjet recording method according to 7), wherein the recording material is an information transmission sheet;
9)
The ink jet recording method according to 8), wherein the information transmission sheet is a sheet having an ink receiving layer containing a porous white inorganic substance,
10)
An ink jet printer loaded with a container containing the aqueous ink composition according to 5) or 6) above;
11)
a) The azo compound according to any one of 1) to 4) or a tautomer thereof, or a salt thereof,
b) The water-based ink composition as described in 5) or 6) above, and
c) A colored body colored by any one of the three methods described in 7) above,
About.

The azo compound of the present invention or a tautomer thereof, or a salt thereof, and an ink composition containing the same are suitably used as an ink for inkjet recording. In addition, when recorded on inkjet paper, it has particularly excellent bronzing resistance, very high print density, excellent color rendering, low chroma, high-quality black hue, and ( Ozone) Excellent fastness such as gas. Therefore, the ink composition containing the azo compound of the present invention or a tautomer thereof, or a salt thereof is extremely useful as a black ink for inkjet recording.

Hereinafter, the present invention will be described in detail.
For the sake of convenience, in the present specification, the “azo compound of the present invention”, including all of the “azo compound of the present invention or a tautomer thereof, or a salt thereof”, will be simply described below.
Here, examples of the tautomer include structures represented by the following formulas (3) and (4). In formulas (3) and (4), R ^{1 to} R ¹³ have the same meaning as in formula (1).

In the above formula (1), R ¹ represents a (C1-C4) alkyl group or a (C1-C4) alkyl group substituted with a carboxy group.

Examples of the (C1 to C4) alkyl group for R ¹ include a linear or branched unsubstituted group, and a linear group is preferable. Specific examples include linear groups such as methyl, ethyl, n-propyl, and n-butyl groups; branched chains such as isopropyl, isobutyl, sec-butyl, and tert-butyl groups; etc. Is mentioned. Preferable specific examples include a methyl group and an n-propyl group, and a methyl group is more preferable.

Examples of the (C1-C4) alkyl group substituted with a carboxy group in R ¹ include those in which any of the carbon atoms of the unsubstituted (C1-C4) alkyl group is substituted with a carboxy group. The substitution position of the carboxy group is not particularly limited, but it is preferably substituted at the end of the alkyl group, and the number of substitution of the carboxy group is 1 or 2, preferably 1. Specific examples include a carboxymethyl group and a 2-carboxyethyl group. A preferred specific example is a carboxymethyl group.

R ¹ is preferably a (C1 to C4) alkyl group or a (C1 to C4) alkyl group substituted with a carboxy group, more preferably a (C1 to C4) alkyl group.
More preferred is a methyl group or an n-propyl group. Particularly preferred is a methyl group.

In the formula (1), ^{R 2} represents a cyano group.

In the above formula (1), R ³ and R ⁴ each independently represents a hydrogen atom, a (C1-C4) alkoxy group, or a sulfo group.

Examples of the (C1 to C4) alkoxy group in R ³ and R ⁴ include a linear or branched unsubstituted group, and a linear group is preferable. Specific examples include straight-chain groups such as methoxy group, ethoxy group, n-propoxy group and n-butoxy group; branched chains such as isopropoxy group, isobutoxy group, sec-butoxy group and tert-butoxy group; Etc. In these, a methoxy group is more preferable.

Examples of R ³ and R ⁴ include a hydrogen atom, a (C1 to C4) alkoxy group, or a sulfo group, one of which is a methoxy group, the other is a sulfo group, or one of which is a hydrogen atom and the other is a sulfo group. A combination of groups is preferred. More preferably, one is a combination of a methoxy group and the other is a sulfo group.
The substitution position of R ³ and R ⁴ is not particularly limited, but when either one is a hydrogen atom and the other is a sulfo group, the sulfo group is any of the four carbon atoms that do not constitute the imidazole ring of the benzimidazolopyridone ring. It is preferable to substitute the crab.

The compound represented by the above formula (1) of the present invention may be used as a mixture containing at least two kinds of positional isomers at the substitution positions of R ³ and R ⁴ from the viewpoint of ease of synthesis and low cost. Good.

As a preferred combination of R ^{1 to} R ⁴ in the formula (1), R ¹ is a (C1 to C4) alkyl group (preferably a methyl group or an n-propyl group, more preferably a methyl group), R ² is a cyano group, R ³ is a hydrogen atom or a methoxy group (preferably a methoxy group), and R ⁴ is a combination of a sulfo group.

In the above formula (1), R ⁵ and R ⁷ are each independently a (C1-C4) alkylthio group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group Represents.

The (C1-C4) alkylthio group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group in R ⁵ and R ⁷ is a (C1-C4) alkylthio group. Those having these substituents at any carbon atom can be mentioned. The number of the substituents is usually 1 or 2, preferably 1. The position of the substituent is not particularly limited, but is preferably substituted with a carbon atom other than the carbon atom to which the sulfur atom in the alkylthio group is bonded.
Specific examples include 2-hydroxyethylthio group, 2-hydroxypropylthio group, 3-hydroxypropylthio group, 2-sulfoethylthio group, 3-sulfopropylthio group, 2-carboxyethylthio group, 3-carboxy. Examples include propylthio group and 4-carboxybutylthio group.

Of these, preferable R ⁵ and R ⁷ include a sulfo (C1 to C4) alkylthio group or a carboxy (C1 to C4) alkylthio group, more preferably a sulfo (C1 to C4) alkylthio group, and 3-sulfopropylthio group. More preferred are groups.

In the above formula (1), R ⁶ and R ⁸ each independently represents a (C1-C4) alkylcarbonylamino group.

In the above formula (1), examples of the (C1 to C4) alkylcarbonylamino group in R ⁶ and R ⁸ include those in which the alkyl moiety is linear or branched, and linear is preferable. Specific examples include straight-chain groups such as acetylamino group (methylcarbonylamino group), propionylamino group (ethylcarbonylamino group), n-propylcarbonylamino group, n-butylcarbonylamino group; isopropylcarbonylamino group, Branched chain such as isobutylcarbonylamino group, sec-butylcarbonylamino group, pivaloylamino group (tert-butylcarbonylamino group) and the like, and acetylamino group is preferable.

A preferred combination of R ⁵ and R ⁶ is that R ⁵ is a sulfo (C1-C4) alkylthio group, R ⁶ is a combination of acetylamino groups, R ⁵ is a 3-sulfopropylthio group, and R ⁶ is an acetylamino group. A combination is more preferred. The same applies to R ⁷ and R ⁸ .

In the above formula (1), R ⁹ represents a sulfo (C1-C4) alkoxy group.

Examples of the sulfo (C1-C4) alkoxy group for R ⁹ include those having a sulfo group at any carbon atom in the (C1-C4) alkoxy group. The number of the substituents is usually 1 or 2, preferably 1. The position of the substituent is not particularly limited, but is preferably substituted with a carbon atom other than the carbon atom to which the oxygen atom in the alkoxy group is bonded.
Specific examples include 2-sulfoethoxy group, 3-sulfopropoxy group, 4-sulfobutoxy group and the like.

Among these, preferable R ⁹ includes a 3-sulfopropoxy group and a 4-sulfobutoxy group, and a 3-sulfopropoxy group is more preferable.

In the above formula ^{(1), R 10} represents a methyl group or a halogen atom.

Specific examples of the halogen atom for R ¹⁰ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, with a chlorine atom being preferred.

R ¹⁰ is preferably a methyl group or a chlorine atom.

In the above formula (1), R ^{11 to} R ¹³ each independently represents a hydrogen atom, a sulfo group, or a halogen atom. However, when R ¹⁰ is a methyl group, one of R ^{11 to} R ¹³ is a hydrogen atom, the other two are sulfo groups, and when R ¹⁰ is a halogen atom, 1 of R ^{11 to} R ¹³ is 1 One is a hydrogen atom, one is a halogen atom, and the other is a sulfo group.

In the above formula (1), examples of the halogen atom in R ^{11 to} R ¹³ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a chlorine atom is preferable.

A preferred combination of R ^{11 to} R ^{13 is} a combination in which R ¹¹ is a hydrogen atom, R ¹² is a sulfo group or a chlorine atom, and R ¹³ is a sulfo group.

In the formula (1), more preferable R ^{11 to} R ¹³ can specify the substitution position and the like.
That is, in the benzene ring substituted by R ^{11 to} R ^13, when the substitution position of the azo group is 1-position, R ¹¹ is 2-position, R ¹² is 3-position or 4-position, and R ¹³ is 5-position or Those substituted at the 6-position are preferred.

Specific examples of preferable combinations in the formulas (1) and (2) include the following combinations (i) to (v). Among these, (ii) to (v) are more preferable, and (iv) or (v) is more preferable.
(I)
R ¹ is a methyl group;
R ² is a cyano group;
R ³ is a hydrogen atom; or a methoxy group;
R ⁴ is a sulfo group;
(C1-C4) alkylthio groups substituted with a sulfo group or a carboxy group for R ⁵ ;
R ⁶ is a (C1-C4) alkylcarbonylamino group;
(C1-C4) alkylthio group in which R ⁷ is substituted with a sulfo group or a carboxy group;
R ⁸ is a (C1-C4) alkylcarbonylamino group;
R ⁹ is a sulfo (C1-C4) alkoxy group;
R ¹⁰ is a methyl group; or a chlorine atom;
A combination in which R ^{11 to} R ¹³ are each independently a hydrogen atom; a sulfo group; or a chlorine atom.
(Ii)
R ¹ is a methyl group;
R ² is a cyano group;
R ³ is a methoxy group;
R ⁴ is a sulfo group;
R ⁵ is a sulfo (C1-C4) alkylthio group;
R ⁶ is a (C1-C4) alkylcarbonylamino group;
R ⁷ is a sulfo (C1-C4) alkylthio group;
R ⁸ is a (C1-C4) alkylcarbonylamino group;
R ⁹ is a sulfo (C1-C4) alkoxy group;
R ¹⁰ is a methyl group;
R ¹¹ is a hydrogen atom;
R ¹² is a sulfo group;
A combination in which R ¹³ is a sulfo group;
(Iii)
R ¹ is a methyl group;
R ² is a cyano group;
R ³ is a methoxy group;
R ⁴ is a sulfo group;
R ⁵ is a sulfo (C1-C4) alkylthio group;
R ⁶ is a (C1-C4) alkylcarbonylamino group;
R ⁷ is a sulfo (C1-C4) alkylthio group;
R ⁸ is a (C1-C4) alkylcarbonylamino group;
R ⁹ is a sulfo (C1-C4) alkoxy group;
R ¹⁰ is a chlorine atom;
R ¹¹ is a hydrogen atom;
R ¹² is a chlorine atom;
A combination in which R ¹³ is a sulfo group;
(Iv)
R ¹ is a methyl group;
R ² is a cyano group;
R ³ is a methoxy group;
R ⁴ is a sulfo group;
R ⁵ is a sulfo (C1-C4) alkylthio group;
R ⁶ is an acetylamino group;
R ⁷ is a sulfo (C1-C4) alkylthio group;
R ⁸ is an acetylamino group;
R ⁹ is a sulfopropoxy group; or a sulfobutoxy group;
R ¹⁰ is a methyl group;
R ¹¹ is a hydrogen atom;
R ¹² is a sulfo group;
A combination in which R ¹³ is a sulfo group;
(V)
R ¹ is a methyl group;
R ² is a cyano group;
R ³ is a methoxy group;
R ⁴ is a sulfo group;
R ⁵ is a sulfo (C1-C4) alkylthio group;
R ⁶ is an acetylamino group;
R ⁷ is a sulfo (C1-C4) alkylthio group;
R ⁸ is an acetylamino group;
R ⁹ is a sulfopropoxy group; or a sulfobutoxy group;
R ¹⁰ is a chlorine atom;
R ¹¹ is a hydrogen atom;
R ¹² is a chlorine atom;
A combination in which R ¹³ is a sulfo group;

The compound which combined the preferable thing described about the various substituents in the said Formula (1), its combination, its substitution position, etc. is more preferable, and what combined the more preferable things is further more preferable. The same applies to preferable ones or combinations of preferable ones and more preferable ones.

A more preferred compound of the above formula (1) is a compound represented by the above formula (2). In formula (2), R ^{1 to} R ¹³ represent the same meaning as in formula (1).

The tetrakisazo compound of the present invention represented by the formula (1) can be synthesized, for example, by the following method. In addition, the structural formula of the compound in each process shall be represented with the form of a free acid. In the following formulas (5) to (12), R ^{1 to} R ¹³ represent the same meaning as in the above formula (1).
A compound represented by the following formula (5) is diazotized by a conventional method, and the obtained diazo compound and a compound represented by the following formula (6) are subjected to a coupling reaction by a conventional method, and represented by the following formula (7). To obtain the compound.

The obtained compound represented by the above formula (7) is diazotized by a conventional method, and then the obtained diazo compound and a compound represented by the following formula (8) are subjected to a coupling reaction by a conventional method, The compound represented by (9) is obtained.

The obtained compound represented by the above formula (9) is diazotized by a conventional method, and then the obtained diazo compound and a compound represented by the following formula (10) are subjected to a coupling reaction by a conventional method. The compound represented by (11) is obtained.

By diazotizing the obtained compound represented by the above formula (11) by a conventional method, the obtained diazo compound and a compound represented by the following formula (12) are subjected to a coupling reaction by a conventional method. The azo compound of the present invention represented by the above formula (1) can be obtained.

The compound represented by the above formula (12) can be synthesized according to the method described in Patent Document 3.

Although it does not specifically limit as a suitable specific example of the azo compound of this invention represented by Formula (1), The compound etc. which are shown by the structural formula given to the following Table 1 thru | or 14 are mentioned.
In each table, functional groups such as sulfo group and carboxy group are described in the form of free acid for convenience. In the following formula, Ac represents an acetyl group.

The diazotization of the compound represented by the above formula (5) is carried out by a method known per se, for example, a nitrite such as -5 to 30 ° C, preferably 0 to 15 ° C in an inorganic acid medium. It is carried out using an alkali metal nitrite such as sodium nitrite.
Coupling of the diazotized compound of the compound represented by the above formula (5) and the compound represented by the above formula (6) is also carried out under known conditions. It is advantageous to carry out in water or an aqueous organic medium, for example at a temperature of -5 to 30 ° C., preferably 0 to 25 ° C., and at an acidic to neutral pH value, for example pH 1 to 6. Since the diazotization reaction liquid is acidic and the reaction system is further acidified by the progress of the coupling reaction, the pH value is adjusted to the preferred pH condition of the reaction liquid by adding a base. Examples of the base that can be used include alkali metal hydroxides such as lithium hydroxide and sodium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate, acetates such as sodium acetate, ammonia, and organic amines. .
The compound represented by the above formula (5) and the compound represented by the above formula (6) are used in a substantially stoichiometric amount.

The diazotization of the compound represented by the formula (7) is carried out by a method known per se, for example, a nitrite such as -5 to 40 ° C., preferably 5 to 30 ° C. in an inorganic acid medium. It is carried out using an alkali metal nitrite such as sodium nitrite.
Coupling of the diazotized compound of the compound represented by the above formula (7) and the compound represented by the above formula (8) is also carried out under known conditions. It is advantageous to carry out in water or an aqueous organic medium, for example at a temperature of −5 to 40 ° C., preferably 10 to 30 ° C., and at an acidic to neutral pH value, for example pH 2-7. Since the diazotization reaction liquid is acidic and the reaction system is further acidified by the progress of the coupling reaction, the pH value is adjusted to the preferred pH condition of the reaction liquid by adding a base. The same base as described above can be used.
The compound represented by the above formula (7) and the compound represented by the above formula (8) are used in a substantially stoichiometric amount.

The diazotization of the compound represented by the above formula (9) is carried out by a method known per se, for example, nitrite such as -5 to 50 ° C, preferably 5 to 40 ° C in an inorganic acid medium. It is carried out using an alkali metal nitrite such as sodium nitrite.
Coupling of the diazotized product of the compound represented by the above formula (9) and the compound represented by the above formula (10) is also carried out under conditions known per se. It is advantageous to carry out in water or an aqueous organic medium, for example at a temperature of −5 to 50 ° C., preferably 10 to 40 ° C., and at an acidic to neutral pH value, for example pH 2-7. Since the diazotization reaction liquid is acidic and the reaction system is further acidified by the progress of the coupling reaction, the pH value is adjusted to the preferred pH condition of the reaction liquid by adding a base. The same base as described above can be used.
The compound represented by the above formula (9) and the compound represented by the above formula (10) are used in a substantially stoichiometric amount.

The diazotization of the compound represented by the above formula (11) is also carried out by a method known per se, for example, a nitrite such as, for example, -5 to 50 ° C., preferably 10 to 40 ° C. in an inorganic acid medium. It is carried out using an alkali metal nitrite such as sodium nitrite.
Coupling of the diazotized compound of the compound represented by the above formula (11) and the compound represented by the above formula (12) is also carried out under conditions known per se. It is advantageous to carry out in water or an aqueous organic medium, for example at a temperature of −5 to 50 ° C., preferably 10 to 40 ° C., and at a weakly acidic to alkaline pH value. It is preferably carried out at a weakly acidic to weakly alkaline pH value, for example, pH 5 to 10, and the pH value is adjusted by adding a base. The same base as described above can be used.
The compound represented by the above formula (11) and the compound represented by the above (12) are used in a substantially stoichiometric amount.

The salt of the azo compound represented by the above formula (1) is a salt with an inorganic or organic cation. Among them, specific examples of inorganic salts include alkali metal salts, alkaline earth metal salts, and ammonium salts, and preferred inorganic salts are lithium, sodium, potassium salts, and ammonium salts. Examples of the salt with an organic cation include, but are not limited to, a salt with a quaternary ammonium ion represented by the following formula (13).
In addition, the free acid of the azo compound of the present invention, its tautomer, and various salts thereof may be a mixture. For example, any combination such as a mixture of sodium salt and ammonium salt, a mixture of free acid and sodium salt, a mixture of lithium salt, sodium salt, and ammonium salt may be used. Depending on the type of salt, the physical properties such as solubility may differ, and if necessary, the type of salt is selected as appropriate, or if multiple salts are included, the ratio is changed to meet the purpose. A mixture having physical properties can also be obtained.

In the above formula (13), Z ¹ , Z ² , Z ³ , and Z ⁴ are each independently a group selected from the group consisting of a hydrogen atom, an unsubstituted alkyl group, a hydroxyalkyl group, and a hydroxyalkoxyalkyl group. And at least one is a group other than a hydrogen atom.
Specific examples of the alkyl group of Z ^{1 to} Z ⁴ in the above formula (13) include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl and the like. Specific examples of the group include hydroxy (C1-C4) alkyl groups such as hydroxymethyl, hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 4-hydroxybutyl, 3-hydroxybutyl, 2-hydroxybutyl and the like. Specific examples of the hydroxyalkoxyalkyl group include hydroxyethoxymethyl, 2-hydroxyethoxyethyl, 3-hydroxyethoxypropyl, 2-hydroxyethoxypropyl, 4-hydroxyethoxybutyl, 3-hydroxyethoxybutyl, and 2-hydroxyethoxy. It includes hydroxy (C1 ~ C4) alkoxy (C1 ~ C4) alkyl group chill like. Of these, hydroxyethoxy (C1-C4) alkyl is preferred. Particularly preferred is a hydrogen atom; methyl; hydroxy (C1-C4) alkyl such as hydroxymethyl, hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 4-hydroxybutyl, 3-hydroxybutyl, 2-hydroxybutyl, etc. Groups: hydroxyethoxy (C1-C4) such as hydroxyethoxymethyl, 2-hydroxyethoxyethyl, 3-hydroxyethoxypropyl, 2-hydroxyethoxypropyl, 4-hydroxyethoxybutyl, 3-hydroxyethoxybutyl, 2-hydroxyethoxybutyl, etc. Alkyl group; and the like.

Specific examples of combinations of Z ¹ , Z ² , Z ³ , and Z ^{4 in} the preferred compound represented by the formula (13) are shown in Table 15 below.

As a method of synthesizing a desired salt of the azo compound represented by the above formula (1) of the present invention, after completion of the final step in the synthesis reaction of the compound represented by the above formula (1), a desired inorganic salt Or a method of salting out by adding an organic quaternary ammonium salt to the reaction solution; obtained after adding a mineral acid such as hydrochloric acid to the reaction solution and isolating the azo compound from the reaction solution in the form of a free acid. The free acid is washed with water, acidic water, an aqueous organic medium or the like as necessary to remove impurities such as attached inorganic salts, and again in the aqueous medium (preferably in water). And a method of forming a salt by adding an organic base corresponding to the desired inorganic base or the above-described quaternary ammonium salt. By such a method, the salt of the target azo compound can be obtained in the form of a solution or a precipitated solid. Here, acidic water refers to water obtained by dissolving a mineral acid such as sulfuric acid or hydrochloric acid or an organic acid such as acetic acid in water. The aqueous organic medium is an admixture of water and an organic substance and / or an organic solvent that are miscible with water.
Examples of the water-miscible organic substance and organic solvent include water-soluble organic solvents described later.
Examples of inorganic salts used when the azo compound represented by the above formula (1) is used as a desired salt include halogen salts of alkali metals such as lithium chloride, sodium chloride and potassium chloride; lithium carbonate, sodium carbonate, carbonate Alkali metal carbonates such as potassium; Alkali metal hydroxides such as lithium hydroxide, sodium hydroxide and potassium hydroxide; Halogen salts of ammonium ions such as ammonium chloride and ammonium bromide; Ammonium hydroxide (ammonia water) And the like.
Examples of organic cation salts include halogen salts of quaternary ammonium ions represented by the above formula (13) such as diethanolamine hydrochloride and triethanolamine hydrochloride.

The ink composition of the present invention will be described. By making the azo compound represented by the above formula (1) of the present invention into an aqueous composition containing the compound, it is possible to dye a material made of cellulose. In addition, it is possible to dye materials having a carbonamide bond, and it can be widely used for dyeing leather, fabrics, paper, and the like. On the other hand, a typical use of the compound of the present invention is an ink composition dissolved in a liquid medium, and is preferably used as an ink composition for inkjet recording.

The reaction liquid containing the compound represented by the above formula (1), for example, the reaction liquid after the final step in the synthesis reaction of the compound represented by the above formula (1) is directly used for the production of the ink composition. be able to. Further, the reaction solution is dried, for example, spray-dried; the reaction solution is salted out by adding inorganic salts such as sodium chloride, potassium chloride, calcium chloride, sodium sulfate; the reaction solution is treated with hydrochloric acid, sulfuric acid The compound is isolated by a method of acid precipitation by adding a mineral acid such as nitric acid; or a method of acid precipitation by a combination of the above salting-out and acid precipitation; Compositions can also be prepared. The azo compound of the present invention is preferably used after being isolated.

The ink composition of the present invention is usually 0.1 to 20% by mass, preferably 1 to 10% by mass, more preferably 2 to 8% by mass, using the azo compound represented by the above formula (1) of the present invention as a coloring matter. % Water-based ink composition. The ink composition of the present invention is prepared using water as a medium, and may contain a water-soluble organic solvent and an ink preparation agent as necessary within a range that does not impair the effects of the present invention. The water-soluble organic solvent may have a function as a dye-dissolving agent, a drying inhibitor (wetting agent), a viscosity modifier, a penetration accelerator, a surface tension modifier, an antifoaming agent, etc., and the ink composition of the present invention It is preferable to contain them. Examples of the ink preparation agent include antiseptic / antifungal agents, pH adjusters, chelating reagents, rust preventives, water-soluble ultraviolet absorbers, water-soluble polymer compounds, dye solubilizers, antioxidants, and surfactants. These additives may be mentioned. The ink composition of the present invention has a water-soluble organic solvent content of 0 to 30% by mass, preferably 5 to 30% by mass, and an ink preparation agent of 0 to 15% by mass, preferably 0 to 7% by mass, based on the total mass. % May be contained respectively. The remainder other than the above is water. The pH of the ink composition is preferably pH 5 to 11 and more preferably pH 7 to 10 from the viewpoint of improving storage stability. The surface tension of the ink composition is preferably 25 to 70 mN / m, more preferably 25 to 60 mN / m. Furthermore, the viscosity of the ink composition is preferably 30 mPa · s or less, and more preferably 20 mPa · s or less.

In addition to the azo compound of the present invention, the ink composition of the present invention may appropriately contain other toning pigments and the like for the purpose of adjusting the subtle hue of black. Even in such a case, the total mass of the pigment contained in the ink composition of the present invention may be in the above range with respect to the total mass of the ink composition.
Examples of toning dyes include yellow (for example, CI Direct Yellow 34, CI Direct Yellow 58, CI Direct Yellow 86, CI Direct Yellow 132, CI Direct Yellow 161, etc. ), Orange (for example, CI Direct Orange 17, CI Direct Orange 26, CI Direct Orange 29, CI Direct Orange 39, CI Direct Orange 49, etc.), Brown, Scarlet (E.g., CI Direct Red 89), red (e.g., CI Direct Red 62, CI Direct Red 75, CI Direct Red 79, CI Direct Red 80, CI Direct Red 84, CI Direct Red 225, CI Direct Red 226), magenta (for example, CI Direct Red 227), violet, blue, navy, cyan (for example, CI Direct Blue 199, CI Acid Blue 249, etc.), green (for example, Acid Green 1) ), Black (for example, CI Acid Black 2), and other dyes having various hues.
The ink composition of the present invention can be used by blending one or more of these toning dyes as long as the effects obtained by the azo compound of the present invention are not impaired. Even in this case, the total amount of the coloring matter contained in the ink composition may be in the above range. The mixing ratio of the azo compound of the present invention to the toning dye is approximately 20: 1 to 1: 2, preferably 10: 1 to 1: 1, depending on the hue of the toning dye and the like. It is.
When the ink composition of the present invention is used as an ink for ink jet recording, it is preferable to use an ink having a low content of inorganic impurities such as metal cation chloride and sulfate in the azo compound of the present invention. The standard of the content of the inorganic impurities is about 1% by mass or less with respect to the total mass of the pigment. The lower limit may be equal to or lower than the detection limit of the analytical instrument, that is, 0%. In order to produce the azo compound of the present invention with a small amount of inorganic impurities, for example, a method using a reverse osmosis membrane; a dried product or wet cake of the azo compound of the present invention is used as an alcohol such as methanol, preferably (C1-C4) alcohol and water The mixture may be suspended and purified by stirring in a mixed solvent, and the salt may be desalted by a known method such as a method in which the precipitate is separated by filtration and dried;

Specific examples of the water-soluble organic solvent that can be used for preparing the ink composition of the present invention include (C1-C4) such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, and tert-butanol. Alcohols; carboxylic acid amides such as N, N-dimethylformamide, N, N-dimethylacetamide; 2-pyrrolidone, hydroxyethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, N-methylpyrrolidin-2-one, etc. Lactam; cyclic ureas such as 1,3-dimethylimidazolidin-2-one, 1,3-dimethylhexahydropyrimido-2-one; acetone, methyl ethyl ketone, 2-methyl-2-hydroxypentan-4-one Such as ketone or keto alcohol; tetrahydrofuran, dioxane, etc. Ether; ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,4-butylene glycol, 1,6-hexylene glycol, diethylene glycol, triethylene glycol, tetraethylene Mono-, oligo-, or polyalkylene glycols or thioglycols having C2-C6 alkylene units such as glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, thiodiglycol, dithiodiglycol, etc .; trimethylolpropane, glycerin, hexane-1, Polyols such as 2,6-triol (preferably triol); ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol (C1-C4) alkyl ethers of polyhydric alcohols such as monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether (butyl carbitol) triethylene glycol monomethyl ether, triethylene glycol monoethyl ether; γ-butyrolactone; dimethyl sulfoxide; Is mentioned. These organic solvents may be used alone or in combination of two or more.
The water-soluble organic solvent mentioned above contains substances that are solid at room temperature, such as trimethylolpropane, but these are water-soluble even when they are solid, and when dissolved in water Since it can be used for the same purpose as the water-soluble organic solvent, it is described in the category of the water-soluble organic solvent for the sake of convenience.

Hereinafter, antiseptic / antifungal agents, pH adjusters, chelating reagents, rust preventives, water-soluble UV absorbers, water-soluble polymer compounds, dye dissolving agents, antioxidants, and surfactants that can be used as ink preparation agents Describe.

Examples of the antifungal agent include sodium dehydroacetate, sodium benzoate, sodium pyridinethione-1-oxide, ethyl p-hydroxybenzoate, 1,2-benzisothiazolin-3-one, and salts thereof. These are preferably used in the ink composition in an amount of 0.02 to 1.00% by mass.

Examples of preservatives include organic sulfur, organic nitrogen sulfur, organic halogen, haloallylsulfone, iodopropargyl, N-haloalkylthio, nitrile, pyridine, 8-oxyquinoline, benzothiazole. , Isothiazoline, dithiol, pyridine oxide, nitropropane, organotin, phenol, quaternary ammonium salt, triazine, thiazine, anilide, adamantane, dithiocarbamate, brominated indanone, Examples include benzyl bromacetate and inorganic salt compounds. Specific examples of organic halogen compounds include sodium pentachlorophenol, and specific examples of pyridine oxide compounds include, for example, sodium 2-pyridinethiol-1-oxide. Specific examples of isothiazoline compounds Are, for example, 1,2-benzisothiazolin-3-one, 2-n-octyl-4-isothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, 5-chloro-2 -Methyl-4-isothiazolin-3-one magnesium chloride, 5-chloro-2-methyl-4-isothiazolin-3-one calcium chloride, 2-methyl-4-isothiazolin-3-one calcium chloride and the like. Specific examples of other antiseptic / antifungal agents include anhydrous sodium acetate, sodium sorbate, sodium benzoate and the like.

As the pH adjuster, any substance can be used as long as it can control the pH of the ink within a range of about 5 to 11 without adversely affecting the prepared ink. Specific examples thereof include, for example, alkanolamines such as diethanolamine, triethanolamine and N-methyldiethanolamine; hydroxides of alkali metals such as lithium hydroxide, sodium hydroxide and potassium hydroxide; ammonium hydroxide (ammonia water) Alkaline metal carbonates such as lithium carbonate, sodium carbonate, sodium hydrogen carbonate and potassium carbonate; alkali metal salts of organic acids such as potassium acetate; inorganic bases such as sodium silicate and disodium phosphate;

Specific examples of chelating reagents include sodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate, sodium uracil diacetate and the like.

Examples of the rust preventive include acidic sulfite, sodium thiosulfate, ammonium thioglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, dicyclohexylammonium nitrite and the like.

Examples of water-soluble ultraviolet absorbers include sulfonated benzophenone compounds, benzotriazole compounds, salicylic acid compounds, cinnamic acid compounds, and triazine compounds.

Examples of water-soluble polymer compounds include polyvinyl alcohol, cellulose derivatives, polyamines and polyimines.

Examples of the dye solubilizer include ε-caprolactam, ethylene carbonate, urea and the like.

As the antioxidant, for example, various organic and metal complex anti-fading agents can be used. Examples of organic anti-fading agents include hydroquinones, alkoxyphenols, dialkoxyphenols, phenols, anilines, amines, indanes, chromans, alkoxyanilines, heterocycles, and the like.

Examples of the surfactant include known surfactants such as anionic, cationic, and nonionic surfactants.
Anionic surfactants include alkyl sulfonates, alkyl carboxylates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, N-acyl amino acids and their salts, N-acyl methyl taurates, alkyl sulfates Polyoxyalkyl ether sulfate, alkyl sulfate polyoxyethylene alkyl ether phosphate, rosin acid soap, castor oil sulfate ester, lauryl alcohol sulfate ester, alkylphenol type phosphate ester, alkyl type phosphate ester, alkylaryl sulfonate, Examples thereof include diethylsulfosuccinate, diethylhexylsylsulfosuccinate, and dioctylsulfosuccinate.

Examples of the cationic surfactant include 2-vinylpyridine derivatives and poly-4-vinylpyridine derivatives.

Amphoteric surfactants include lauryldimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, coconut oil fatty acid amidopropyldimethylaminoacetic acid betaine, polyoctylpolyaminoethylglycine, imidazoline derivatives, etc. Is mentioned.

Nonionic surfactants include ethers such as polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene dodecylphenyl ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene alkyl ether; Ester systems such as polyoxyethylene oleate, polyoxyethylene distearate, sorbitan laurate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, polyoxyethylene monooleate, polyoxyethylene stearate; 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, 3,5-dimethyl Acetylene glycol (alcohol) type such as lu-1-hexyn-3-ol; trade name Surfynol 104, 105, 82, 465, Olphine STG, etc. manufactured by Nissin Chemical; Polyglycol ether type (for example, SIGMA-ALDRICH) Manufactured by Tergitol 15-S-7, etc.).
The above ink preparation agents are used alone or in combination.

The ink composition of the present invention can be obtained by mixing and stirring the above components in an arbitrary order. If desired, the obtained ink composition may be subjected to microfiltration with a membrane filter or the like in order to remove impurities. When used in ink jet recording, the filtration is preferably performed. The pore diameter of the filter for performing microfiltration is usually 1 to 0.1 μm, preferably 0.8 to 0.1 μm.

The ink composition of the present invention can be used in various fields, but is suitable for a water-based ink for writing, a water-based printing ink, an information recording ink, and the like, and is particularly preferably used as an ink for ink-jet recording. It is suitably used in the ink jet recording method of the present invention.

The ink jet recording method of the present invention is a method for performing recording by using the ink composition of the present invention as ink and ejecting ink droplets of the ink in accordance with a recording signal to adhere to the recording material. In the ink jet recording method of the present invention, there are no particular limitations on the ink head, ink nozzles, and the like used for recording, and the ink recording method can be appropriately selected according to the purpose.
This recording method is a known method, for example, a charge control method that ejects ink using electrostatic attraction force; a drop-on-demand method (pressure pulse method) that uses the vibration pressure of a piezo element; An acoustic ink jet method that irradiates the ink instead of the ink and discharges the ink using the radiation pressure; a thermal ink jet that heats the ink to form bubbles and uses the generated pressure, a so-called bubble jet (registered trademark) method Etc. can be used.

The recording material used in the ink jet recording method of the present invention is not particularly limited, and examples thereof include information transmission sheets such as paper and film, fibers and cloth (cellulose, nylon, wool, etc.), leather, and color filter bases. An information transmission sheet is preferable among them.
The information transmission sheet is preferably a surface-treated sheet, specifically, a sheet, a synthetic paper, a film or other base material provided with an ink receiving layer. The ink receiving layer is formed by, for example, impregnating or coating the above-mentioned base material with a cationic polymer; porous white inorganic substances capable of absorbing pigments in ink, such as porous silica, alumina sol, special ceramics, etc. It is provided by a method such as coating with a hydrophilic polymer such as pyrrolidone on the surface of the substrate.
The information transmission sheet provided with such an ink receiving layer is usually called ink jet dedicated paper (film), glossy paper (film) or the like. Specific examples include Canon Inc., trade name: Professional Photo Paper, Super Photo Paper, or Matt Photo Paper; Seiko Epson Corporation, trade name: Photo Paper (Glossy), PM Matt Paper, Crispia; Japan Hewlett-Packard Co. Made by company, product name Advanced Photo Paper, Premium Plus Photo Paper, Premium Glossy Film or Photo Paper, etc., and are available as commercial products. Of course, plain paper can also be used.

Among the information transmission sheets described above, it is known that an image recorded on a sheet coated with a porous white inorganic substance has a particularly large discoloration due to ozone gas. However, since the ink composition of the present invention is excellent in ozone gas resistance, a great effect is exhibited even when ink jet recording is performed on such a recording material.

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 ink composition may be loaded at a predetermined position of an ink jet printer and recorded on the recording material by the above method.
The ink jet recording method of the present invention comprises the black ink composition of the present invention and, for example, the known magenta, cyan, yellow, and as necessary, green, blue (or violet), red (or orange), etc. These ink compositions of the respective colors can also be used in combination.
The ink composition of each color is injected into each container, and each container is loaded into a predetermined position of the ink jet printer and used for ink jet recording in the same manner as the container containing the black ink composition of the present invention.

The colored body of the present invention is
a) The azo compound according to any one of 1) to 4) or a tautomer thereof, or a salt thereof,
b) The water-based ink composition as described in 5) or 6) above, and
c) A substance colored by any one of the three methods of the ink jet recording method described in 7) above [the three of these a) to c)].
Although there is no restriction | limiting in particular about the substance to be colored, The recording material etc. which are used for said inkjet recording method are mentioned preferably.

The azo compound of the present invention is a black pigment. This compound is easy to synthesize and inexpensive, and has a feature of low saturation, and therefore exhibits a more preferable hue as black. Moreover, since it is excellent in water solubility, the filterability by a membrane filter in the process of manufacturing an ink composition is good.
Further, the ink composition of the present invention containing the azo compound is an aqueous black ink composition, and has good storage stability without solid precipitation, physical property change, color change, etc. after long-term storage.
An image recorded with the ink composition of the present invention has particularly excellent bronzing resistance, high print density, low color rendering, low chroma, and high-quality black hue. Excellent fastness such as ozone gas resistance, light resistance, moisture resistance and water resistance. Furthermore, when used in combination with ink compositions containing magenta, cyan, and yellow dyes, full-color ink jet recording with excellent fastness and storage stability is possible.
As described above, the ink composition containing the azo compound of the present invention can be used as an ink for ink jet recording, a writing instrument, and the like, and has excellent ejection stability. Is preferred.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited at all by the following example.
In the text, “parts” and “%” are based on mass unless otherwise specified.
Each synthesis reaction, crystallization and other operations were carried out with stirring unless otherwise specified. In the following formulas, acidic functional groups such as sulfo and carboxy are represented in the form of free acid. The pH value and the reaction temperature in the synthesis reaction are both measured values in the reaction system.
Further, the maximum absorption wavelength (λmax) of the synthesized compound was measured in an aqueous solution having a pH of 7 to 8, and the measured value of the measured compound was described in Examples.
The azo compounds of the present invention synthesized in the following examples all showed a solubility of 100 g / liter or more in water.

[Example 1]
(Process 1)
41.8 parts of 4-chloro-3-nitroaniline was dissolved in 60.0 parts of N-methyl-2-pyrrolidone, and 35.2 parts of acetic anhydride was added dropwise over about 15 minutes. After dropping, the mixture was reacted at 40 to 50 ° C. for 2 hours, and then the reaction solution was added to 400 parts of water. After stirring at room temperature for 30 minutes, the precipitated solid was filtered, and the obtained solid was washed with 100 parts of water on a funnel, separated and dried, and 63.0 parts of a compound represented by the following formula (14). Got.

(Process 2)
42.9 parts of the compound represented by the formula (14) obtained in Example 1 (Step 1) was dissolved in 115.0 parts of N-methyl-2-pyrrolidone, and sodium 3-mercaptopropanesulfonate was dissolved therein. 40.9 parts and 29.0 parts of potassium carbonate were added. After the addition, the mixture was heated to 130 to 140 ° C. and reacted at the same temperature for 2 hours. After further adding 3.6 parts of sodium 3-mercaptopropanesulfonate, the mixture was reacted at 130 to 140 ° C. for 1 hour. After cooling to 60 ° C., the reaction solution was added to 700 parts of 2-propanol. After cooling to room temperature, the resulting solid was collected by filtration. The obtained wet cake was dissolved in 300 parts of water, adjusted to pH 3.0 to 4.0 by adding 35% hydrochloric acid, salted out with sodium chloride, and the precipitated solid was collected by filtration, 205.3 parts of a wet cake containing the compound represented by (15) was obtained.

(Process 3)
In 150 parts of water, 102.6 parts of a wet cake of the compound represented by the formula (15) obtained in Example 1 (Step 2), 1.6 parts of activated carbon, and 0.4% of anhydrous iron (III) chloride. Then, 15.9 parts of 80% hydrazine hydrate was added dropwise over about 30 minutes. After heating to 90 ° C., the reaction was carried out at the same temperature for 1.5 hours. After cooling to 40 ° C., insoluble matters were removed by filtration, and the filtrate was cooled to room temperature. The pH was adjusted to 1.0 to 1.5 by adding 50% sulfuric acid, and the precipitated solid was collected by filtration to obtain 62.3 parts of a wet cake containing a compound represented by the following formula (16).

(Process 4)
After adding 5.1 parts of aniline-2,4-disulfonic acid represented by the following formula (17) to 50 parts of water, an aqueous solution was obtained by adding a 25% aqueous sodium hydroxide solution to pH 4.0 to 5.0. . After adding 6.3 parts of 35% hydrochloric acid, 4.2 parts of 40% sodium nitrite aqueous solution was added and allowed to react for about 30 minutes. The sulfamic acid 0.8 part was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, after adding 9.5 parts of a wet cake of the compound represented by the formula (16) obtained in Example 1 (Step 3) to 100 parts of water, pH 4. An aqueous solution was obtained as 0 to 5.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 2.0 to 4.0 by adding a 15% aqueous sodium carbonate solution, then sodium chloride was added to adjust the pH to 0.8 to 1.0 with 35% hydrochloric acid. Salted out. The precipitated solid was collected by filtration to obtain 24.8 parts of a wet cake containing a compound represented by the following formula (18).

(Process 5)
After adding the total amount of the wet cake of the compound represented by the formula (18) obtained in Example 1 (Step 4) to 80 parts of water, a pH of 6.0 to 7.0 was obtained by adding a 25% aqueous sodium hydroxide solution. As an aqueous solution was obtained. After adding 5.63 parts of 35% hydrochloric acid, 3.8 parts of 40% aqueous sodium nitrite solution was added and allowed to react for about 30 minutes. The sulfamic acid 0.8 part was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, after adding 8.6 parts of a wet cake of the compound represented by the formula (16) obtained in Example 1 (step 3) to 100 parts of water, pH 4. An aqueous solution was obtained as 0 to 5.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 2.0 to 2.5 by adding 15% aqueous sodium carbonate solution, then sodium chloride was added, and pH 0.8 to 1.0 was added by adding 35% hydrochloric acid. As acidified. The precipitated solid was collected by filtration to obtain 33.2 parts of a wet cake containing a compound represented by the following formula (19).

(Step 6)
To 100 parts of water, 33.2 parts of a wet cake of the compound represented by the formula (19) obtained in Example 1 (Step 5) was added, and dissolved by stirring. After adding 4.7 parts of 35% hydrochloric acid, 3.2 parts of 40% aqueous sodium nitrite solution was added and stirred for about 30 minutes. 0.4 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, 3.9 parts of a compound represented by the following formula (20) obtained by the method described in JP-A-2004-083492 is added to 80 parts of water, and pH 6.0 is added by adding a 25% aqueous sodium hydroxide solution. An aqueous solution was obtained as ˜7.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 3.0 to 4.5 by adding a 15% aqueous sodium carbonate solution. After the pH was adjusted to 8.0 to 8.5 by addition of 25% aqueous sodium hydroxide solution, sodium chloride was added. The precipitated solid was collected by filtration to obtain 55.4 parts of a wet cake containing a compound represented by the following formula (21).

(Step 7)
15.2 parts of 2-methyl-6-nitroaniline were dissolved in 300 parts of methanol. The resulting solution was transferred into an autoclave, 2.0 parts of 5% Pd / carbon was added, and the mixture was reacted at 20 to 30 ° C. under a hydrogen pressure of 0.2 to 0.5 MPa until no hydrogen was absorbed. The reaction was further continued at the same temperature for 30 minutes. The catalyst (5% Pd / carbon) was separated by filtration to obtain a solution (filtrate) containing a compound represented by the following formula (22).

(Process 8)
To 200 parts of the solution containing the compound represented by the formula (22) obtained in Example 1 (Step 7), 13.0 parts of methyl cyanoacetate was added and refluxed for 30 minutes. Then, methanol was concentrated under reduced pressure, 100 parts of water and then sodium carbonate were added to adjust the pH to 7.0 to 7.5, and the precipitated solid was separated by filtration and dried to obtain 8.3 parts of a compound represented by the following formula (23).

(Step 9)
To 100 parts of ethanol were added 8.3 parts of the compound represented by the formula (23) obtained in Example 1 (Step 8), 12.0 parts of 28% sodium methoxide, and 7.2 parts of methyl acetoacetate. After refluxing for 30 minutes, ethanol was concentrated under reduced pressure, 100 parts of water and then 35% hydrochloric acid were added to adjust the pH to 7.0 to 7.5, and the precipitated solid was separated by filtration and dried to obtain the following formula (24). 11.1 parts of a compound represented by the formula: The obtained compound represented by the following formula (24) was a mixture of compounds in which a methoxy group was substituted with b or c.

(Process 10)
After slowly adding 5.6 parts of the compound represented by the formula (24) obtained in Example 1 (step 9) to 77 parts of 8% fuming sulfuric acid at 5 to 10 ° C., 1. The reaction was allowed for 5 hours. The reaction solution was dropped into 150 parts of ice water over about 10 minutes, stirred at 65 to 70 ° C. for 30 minutes, and the precipitated solid was separated by filtration to obtain a wet solution of the compound represented by the following formula (25). 24.4 parts of cake were obtained. In the compound represented by the following formula (25), the methoxy group is at the position b and the substitution position of the sulfo group is a, c, or d, or the methoxy group is at the position c, and the sulfo group Was a mixture of compounds in which the substitution position was a, b, or d.

(Step 11)
To 80 parts of water, 55.4 parts of a wet cake of the compound represented by the formula (21) obtained in Example 1 (Step 6) was added and dissolved by stirring. After adding 4.5 parts of 35% hydrochloric acid, 2.5 parts of 40% aqueous sodium nitrite solution was added and stirred for about 30 minutes. 0.5 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, 4.5 parts of a wet cake of the compound represented by formula (25) obtained in Example 1 (Step 10) above was added to 80 parts of water, and a 25% aqueous sodium hydroxide solution was added to adjust the pH to 7.5- The solution was adjusted to 8.5 to obtain an aqueous solution. The diazo reaction solution obtained above was added dropwise to this aqueous solution at 15 to 30 ° C. over about 30 minutes. At this time, an aqueous sodium carbonate solution was added to maintain the pH of the reaction solution at 6.5 to 7.5, and the reaction was further continued for 2 hours while maintaining the same temperature and pH adjustment. Sodium chloride was added to the reaction solution for salting out, and the precipitated solid was separated by filtration to obtain 65.0 parts of a wet cake. The obtained wet cake was dissolved in 150 parts of water, the pH was adjusted to 7.0 to 7.5 with 35% hydrochloric acid, 400 parts of methanol was added, and the precipitated solid was collected by filtration. The obtained wet cake was again dissolved in 100 parts of water, and then 300 parts of methanol was added. The precipitated solid was separated by filtration and dried to obtain 9.0 parts of a compound represented by the following formula (26) of the present invention in the form of a black powder as a sodium salt. λmax: 604 nm.

[Example 2]
(Process 1)
After adding 8.3 parts of aniline-2.5-disulfonic acid represented by the following formula (27) to 50 parts of water, an aqueous solution is obtained by adding a 25% aqueous sodium hydroxide solution to pH 4.0 to 5.0. It was. After adding 9.4 parts of 35% hydrochloric acid, 6.3 parts of 40% aqueous sodium nitrite solution was added and allowed to react for about 30 minutes. 0.6 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, after adding 14.4 parts of a wet cake of the compound represented by the formula (16) obtained in Example 1 (Step 3) to 100 parts of water, pH 4. An aqueous solution was obtained as 0 to 5.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 3.0 to 5.0 by adding a 15% aqueous sodium carbonate solution, then sodium chloride was added to adjust the pH to 0.8 to 1.0 with 35% hydrochloric acid. Salted out. The precipitated solid was collected by filtration to obtain 37.4 parts of a wet cake containing a compound represented by the following formula (28).

(Process 2)
After adding the total amount of the wet cake of the compound represented by the formula (28) obtained in Example 2 (Step 1) to 150 parts of water, pH 6.0 to 7. An aqueous solution was obtained as zero. After adding 7.8 parts of 35% hydrochloric acid, 5.2 parts of 40% aqueous sodium nitrite solution was added and allowed to react for about 30 minutes. 1.0 part of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, after adding 14.2 parts of a wet cake of the compound represented by the formula (16) obtained in Example 1 (Step 3) to 100 parts of water, a pH of 6. was obtained by adding a 25% aqueous sodium hydroxide solution. An aqueous solution was obtained as 0 to 7.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 2.0 to 2.5 by adding 15% aqueous sodium carbonate solution, then sodium chloride was added, and pH 0.8 to 1.0 was added by adding 35% hydrochloric acid. As acidified. The precipitated solid was collected by filtration to obtain 58.8 parts of a wet cake containing a compound represented by the following formula (29).

(Process 3)
To 100 parts of water, 58.8 parts of a wet cake of the compound represented by the formula (29) obtained in Example 2 (Step 2) was added and dissolved by stirring. After adding 6.3 parts of 35% hydrochloric acid, 4.2 parts of 40% aqueous sodium nitrite solution was added and stirred for about 30 minutes. 0.6 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, to 100 parts of water, 5.2 parts of the compound represented by the above formula (20) obtained by the method described in JP-A-2004-083492 is added, and pH 6.0 is added by adding a 25% aqueous sodium hydroxide solution. An aqueous solution was obtained as ˜7.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 3.0 to 4.5 by adding a 15% aqueous sodium carbonate solution. After the pH was adjusted to 7.0 to 8.5 by addition of 25% aqueous sodium hydroxide solution, sodium chloride was added. The precipitated solid was collected by filtration to obtain 36.0 parts of a wet cake containing a compound represented by the following formula (30).

(Process 4)
To 80 parts of water, 36.0 parts of a wet cake of the compound represented by the formula (30) obtained in Example 2 (Step 3) was added and dissolved by stirring. After adding 7.3 parts of 35% hydrochloric acid, 4.2 parts of 40% aqueous sodium nitrite solution was added and stirred for about 30 minutes. 0.5 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, 7.5 parts of a wet cake of the compound represented by the formula (25) obtained in Example 1 (Step 10) above was added to 100 parts of water, and a 25% aqueous sodium hydroxide solution was added to adjust the pH to 7.5- The solution was adjusted to 8.5 to obtain an aqueous solution. The diazo reaction solution obtained above was added dropwise to this aqueous solution at 15 to 30 ° C. over about 30 minutes. At this time, an aqueous sodium carbonate solution was added to maintain the pH of the reaction solution at 6.5 to 7.5, and the reaction was further continued for 2 hours while maintaining the same temperature and pH adjustment. After the pH of the reaction solution was adjusted to 7.0 to 7.5 with 35% hydrochloric acid, 400 parts of methanol was added, and the precipitated solid was collected by filtration to obtain 81.5 parts of a wet cake. The obtained wet cake was again dissolved in 100 parts of water, and then 300 parts of methanol was added. The precipitated solid was separated by filtration and dried to obtain 6.7 parts of a compound represented by the following formula (31) of the present invention in the form of a black powder as a sodium salt. λmax: 602 nm.

[Example 3]
(Process 1)
After adding 6.9 parts of 5-amino-2-chlorobenzenesulfonic acid represented by the following formula (32) to 40 parts of water, the aqueous solution is adjusted to pH 5.0 to 7.0 by adding 25% aqueous sodium hydroxide solution. Obtained. After adding 10.5 parts of 35% hydrochloric acid, 6.4 parts of 40% aqueous sodium nitrite solution was added and allowed to react for about 30 minutes. 0.4 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, after adding 9.2 parts of the wet cake of the compound represented by the formula (16) obtained in Example 1 (Step 3) to 40 parts of water, the pH was adjusted to 4. by adding a 25% aqueous sodium hydroxide solution. An aqueous solution was obtained as 0 to 5.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 2.0 to 2.5 by adding a 15% aqueous sodium carbonate solution, and then salted out by adding sodium chloride. The precipitated solid was collected by filtration to obtain 27.5 parts of a wet cake containing a compound represented by the following formula (33).

(Process 2)
After adding the total amount of the wet cake of the compound represented by the formula (33) obtained in Example 3 (Step 1) to 150 parts of water, pH 6.0 to 7. An aqueous solution was obtained as zero. After adding 8.5 parts of 35% hydrochloric acid, 5.2 parts of 40% aqueous sodium nitrite solution was added and reacted for about 30 minutes. 0.5 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, after adding 11.7 parts of a wet cake of the compound represented by the formula (16) obtained in Example 1 (Step 3) to 20 parts of water, a pH of 6. was obtained by adding a 25% aqueous sodium hydroxide solution. An aqueous solution was obtained as 0 to 7.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 2.0 to 2.5 by adding a 15% aqueous sodium carbonate solution, and then salted out by adding sodium chloride. The precipitated solid was collected by filtration to obtain 71.6 parts of a wet cake containing a compound represented by the following formula (34).

(Process 3)
Compound 1 represented by the following formula (35) obtained by using commercially available 2-amino-4-chlorophenol as a raw material in 17.5 parts of water according to the method described in JP-A-2004-75719. Add 3 parts, then dissolve at pH 6.0-7.0 by adding 25% aqueous sodium hydroxide and use 1.9 parts sodium bisulfite and 1.5 parts 35% formalin. To give a methyl-ω-sulfonic acid derivative.
On the other hand, 35.1 parts of a wet cake of the compound represented by the formula (34) obtained in Example 3 (Step 2) was added to 80 parts of water and dissolved by stirring. After adding 3.8 parts of 35% hydrochloric acid, 2.6 parts of 40% aqueous sodium nitrite solution was added and stirred for about 30 minutes. 0.4 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
This diazo reaction solution was dropped into the methyl-ω-sulfonic acid derivative solution obtained above over about 5 minutes. After the dropwise addition, the reaction was allowed to proceed for 3 hours while maintaining the pH at 6.0 to 7.0 by adding a 15% aqueous sodium carbonate solution. The reaction solution was adjusted to pH 11 with sodium hydroxide, stirred at 80 to 95 ° C. for 5 hours while maintaining the same pH, and further sodium chloride was added. The precipitated solid was collected by filtration to obtain 27.0 parts of a wet cake containing a compound represented by the following formula (36).

(Process 4)
To 80 parts of water, 25.1 parts of a wet cake of the compound represented by the formula (36) obtained in Example 3 (Step 3) was added and dissolved by stirring. After adding 4.4 parts of 35% hydrochloric acid, 2.5 parts of 40% aqueous sodium nitrite solution was added and stirred for about 30 minutes. 0.3 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, 4.5 parts of a wet cake of the compound represented by the formula (25) obtained in Example 1 (Step 10) above was added to 100 parts of water, and a 25% aqueous sodium hydroxide solution was added to adjust the pH to 7.5- The solution was adjusted to 8.5 to obtain an aqueous solution. The diazo reaction solution obtained above was added dropwise to this aqueous solution at 15 to 30 ° C. over about 30 minutes. At this time, an aqueous sodium carbonate solution was added to maintain the pH of the reaction solution at 6.5 to 7.5, and the reaction was further continued for 2 hours while maintaining the same temperature and pH adjustment. After the pH of the reaction solution was adjusted to 7.0 to 7.5 with 35% hydrochloric acid, 400 parts of methanol was added, and the precipitated solid was collected by filtration to obtain 20.1 parts of a wet cake. The obtained wet cake was again dissolved in 100 parts of water, and then 300 parts of methanol was added. The precipitated solid was separated by filtration and dried to obtain 1.9 parts of a compound represented by the following formula (37) of the present invention in the form of a black powder as a sodium salt. λmax: 598 nm.

[Example 4]
(Process 1)
After adding 6.0 parts of aniline-3,5-disulfonic acid represented by the following formula (38) to 70 parts of water, an aqueous solution was obtained by adding a 25% aqueous sodium hydroxide solution to a pH of 5.0 to 6.0. . After adding 7.4 parts of 35% hydrochloric acid, 4.2 parts of 40% aqueous sodium nitrite solution was added and allowed to react for about 30 minutes. 0.4 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, after adding 9.3 parts of a wet cake of the compound represented by the formula (16) obtained in Example 1 (Step 3) to 100 parts of water, pH 6 was obtained by adding 25% aqueous sodium hydroxide solution. An aqueous solution was obtained as 0.0 to 7.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 3.0 to 5.0 by adding a 15% aqueous sodium carbonate solution, and then sodium chloride was added. The precipitated solid was collected by filtration to obtain 35.3 parts of a wet cake containing a compound represented by the following formula (39).

(Process 2)
After adding the total amount of the wet cake of the compound represented by the formula (39) obtained in Example 4 (Step 1) to 100 parts of water, pH 6.0 to 7.0 was added by adding a 25% aqueous sodium hydroxide solution. As an aqueous solution was obtained. After adding 6.3 parts of 35% hydrochloric acid, 3.6 parts of 40% aqueous sodium nitrite solution was added and allowed to react for about 30 minutes. 1.0 part of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, after adding 7.9 parts of the wet cake of the compound represented by the formula (16) obtained in Example 1 (Step 3) to 50 parts of water, pH 6 was obtained by adding 25% aqueous sodium hydroxide solution. An aqueous solution was obtained as 0.0 to 7.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 2.0 to 2.5 by adding a 15% aqueous sodium carbonate solution, and then sodium chloride was added. The precipitated solid was collected by filtration to obtain 40.6 parts of a wet cake containing a compound represented by the following formula (40).

(Process 3)
The whole wet cake of the compound represented by the formula (40) obtained in Example 4 (Step 2) was added to 100 parts of water and dissolved by stirring. After adding 5.3 parts of 35% hydrochloric acid, 3.1 parts of 40% aqueous sodium nitrite solution was added and stirred for about 30 minutes. 0.6 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, to 100 parts of water, 5.2 parts of the compound represented by the above formula (20) obtained by the method described in JP-A-2004-083492 is added, and pH 6.0 is added by adding a 25% aqueous sodium hydroxide solution. An aqueous solution was obtained as ˜7.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above over about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 3.0 to 4.5 by adding a 15% aqueous sodium carbonate solution. After the pH was adjusted to 7.0 to 8.5 by addition of 25% aqueous sodium hydroxide solution, sodium chloride was added. The precipitated solid was collected by filtration to obtain 58.6 parts of a wet cake containing a compound represented by the following formula (41).

(Process 4)
The whole wet cake of the compound represented by the formula (41) obtained in Example 4 (Step 3) was added to 80 parts of water and dissolved by stirring. After adding 4.5 parts of 35% hydrochloric acid, 2.6 parts of 40% aqueous sodium nitrite solution was added and stirred for about 30 minutes. 0.5 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
Meanwhile, 4.7 parts of a wet cake of the compound represented by the formula (25) obtained in Example 1 (Step 10) above was added to 100 parts of water, and a 25% aqueous sodium hydroxide solution was added to adjust the pH to 7.5. To 8.5 to obtain an aqueous solution. The diazo reaction solution obtained above was added dropwise to this aqueous solution at 15 to 30 ° C. over about 30 minutes. At this time, an aqueous sodium carbonate solution was added to maintain the pH of the reaction solution at 6.5 to 7.5, and the reaction was further continued for 2 hours while maintaining the same temperature and pH adjustment. After the pH of the reaction solution was adjusted to 7.0 to 7.5 with 35% hydrochloric acid, 400 parts of methanol was added, and the precipitated solid was collected by filtration to obtain 36.1 parts of a wet cake. The obtained wet cake was again dissolved in 100 parts of water, and then 300 parts of methanol was added. The precipitated solid was separated by filtration and dried to obtain 7.1 parts of a compound represented by the following formula (42) of the present invention in the form of a black powder as a sodium salt. λmax: 602 nm.

[(A) Preparation of ink]
[Example 5]
Using the compound of the present invention obtained in Example 1 as a dye, each component was mixed at the composition ratio shown in Table 16 below, stirred for about 1 hour until the solid content was dissolved, and then a 0.45 μm membrane filter. A black ink composition for test was prepared by filtering with (trade name, cellulose acetate filter paper, manufactured by Advantech). In addition, as a surfactant in the following Table 16, Nissin Chemical Co., Ltd. product name Surfynol 104PG50 was used.

[Example 6]
In the same manner as in Example 5, the compound of the present invention obtained in Example 2 was used as a pigment and mixed at the composition ratio shown in Table 16 to prepare a black ink composition by the same method.

[Example 7]
In the same manner as in Example 5, the compound of the present invention obtained in Example 3 was used as a pigment and mixed at the composition ratio shown in Table 16 to prepare a black ink composition by the same method.

[Example 8]
In the same manner as in Example 5, the compound of the present invention obtained in Example 4 was used as a dye, mixed at the composition ratio shown in Table 16, and a black ink composition was prepared in the same manner.

[Comparative Example 1]
A comparative ink was prepared in the same manner as in Example 4 except that the dye represented by the following formula (43) was used as the black dye to be compared. The following various tests conducted using this ink are referred to as Comparative Example 1. In addition, the compound represented by the following formula (43) is the compound described in Example 9 in International Publication No. 2012/081640, and was obtained by following the method described in the literature.

[(B) Inkjet recording]
Using the respective ink compositions obtained in Examples 5 to 8 and Comparative Example 1, inkjet recording was performed on the following printing paper using an inkjet printer (product name: PIXUS iP4500, manufactured by Canon Inc.).
Glossy paper 1: Product made by Canon, Canon photo paper, Glossy Pro PT-101A420
Glossy paper 2: manufactured by Canon Inc., trade name Canon Photographic Paper, Glossy Gold GL-101A450
Glossy paper 3: Product name manufactured by EPSON Co., Ltd. Photographic paper Krispia <High gloss>
Glossy paper 4: Brother Kogyo Co., Ltd., trade name Photo paper BP71GA4
Glossy paper 5: manufactured by Hewlett-Packard, product name Advanced Photo Paper Glossy paper 6: manufactured by Canon, product name Canon Photo Paper / Glossy Pro PT-201A420
At the time of printing, as a test piece for hue evaluation, an image pattern is made so that six gradations of reflection densities of 100%, 85%, 70%, 55%, 40%, and 25% are obtained, and dark black A pale black gradation recorded matter was obtained, and this was used as a test piece to conduct a bronzing evaluation test.
Further, as test pieces for evaluating moisture resistance, lattice-like image patterns having a reflection density of 100% and 0% were prepared to obtain black and white lattice-like recorded matter, which were used as test pieces.
Since the gray scale mode is used at the time of printing, yellow, magenta and cyan recording liquids other than black recording are not used together.

[(C) Evaluation of recorded image]
[(C-1) Evaluation of bronzing property]
Each recorded image obtained using the inks of Examples 5 to 7 and Comparative Example 1 was visually confirmed to confirm the presence or absence of the bronzing phenomenon. The criteria are shown below. The results are shown in Table 17 below.
○: No bronzing △: Bronzing occurs at 100% ×: Bronzing occurs at 85% or less

As is clear from Table 17, Examples 5 to 7 all had better bronzing resistance than Comparative Example 1.

[(C-2) Evaluation of moisture resistance]
In this test, the density change of the recorded image was measured using a colorimeter manufactured by GRETAG-MACBETH, trade name SpectroEye. When measuring colors, all were performed under the conditions of D65 as the light source, DIN NB as the density reference, and a viewing angle of 2 °.
Each recorded image obtained using the inks of Examples 5 to 8 and Comparative Example 1 was air-dried for 24 hours after printing, and a Humidic Chamber IG400 manufactured by Yamato Scientific Co., Ltd. was used. Each test piece was left for 168 hours under the condition of% RH. After the test is completed, color measurement is performed using the above colorimeter, and the color difference (ΔE) is calculated as ((L * after test−L * before test) ² + (a * after test−a * before test)) ² + (b * after test−b * before test) ² ) ^1/2 ) and evaluated according to the following criteria. As the evaluation obtained, a small value indicates that the color change after fading is small and is excellent. The criteria are shown below. The results are shown in Table 18 and Table 19 below.

○: ΔE ≦ 1.00
Δ: 1.00 <ΔE ≦ 1.10
×: 1.10 <ΔE

○: ΔE ≦ 1.15
Δ: 1.15 <ΔE ≦ 1.25
×: 1.25 <ΔE

As is clear from Table 18 and Table 19, all of Examples 5 to 8 had better moisture resistance than Comparative Example 1.

From the above, it can be seen that the ink compositions of Examples 5 to 8 using the compounds of Examples 1 to 4 are better than Comparative Example 1 in bronzing resistance and moisture resistance.

The azo compound of the present invention and an ink composition containing the azo compound are preferably used for black ink for various recordings such as writing instruments, particularly ink jet recording.

Claims

An azo compound represented by the following formula (1), a tautomer thereof, or a salt thereof.

[In Formula (1),
R 1 represents a (C1-C4) alkyl group; or a (C1-C4) alkyl group substituted with a carboxy group;
R 2 represents a cyano group;
R 3 and R 4 each independently represent a hydrogen atom; a (C1-C4) alkoxy group; or a sulfo group;
R 5 represents a (C1-C4) alkylthio group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group;
R 6 represents a (C1-C4) alkylcarbonylamino group;
R 7 represents a (C1-C4) alkylthio group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group;
R 8 represents a (C1-C4) alkylcarbonylamino group;
R 9 represents a sulfo (C1-C4) alkoxy group;
R 10 represents a methyl group; or a halogen atom;
R 11 to R 13 each represents a hydrogen atom; a sulfo group; or a halogen atom.
However, when R 10 is a methyl group, one of R 11 to R 13 is a hydrogen atom, the other two are sulfo groups, and when R 10 is a halogen atom, 1 of R 11 to R 13 is 1 One is a hydrogen atom, one is a halogen atom, and the other is a sulfo group. ]
The azo compound or a tautomer thereof according to claim 1, or a salt thereof, wherein the azo compound represented by the formula (1) is represented by the following formula (2).

[In Formula (2), R 1 to R 13 represent the same meaning as in Formula (1). ]
R 1 is a methyl group;
R 2 is a cyano group;
R 3 is a methoxy group;
R 4 is a sulfo group;
R 5 is a sulfo (C1-C4) alkylthio group;
R 6 is a (C1-C4) alkylcarbonylamino group;
R 7 is a sulfo (C1-C4) alkylthio group;
R 8 is a (C1-C4) alkylcarbonylamino group;
R 9 is a sulfo (C1-C4) alkoxy group;
R 10 is a methyl group;
R 11 is a hydrogen atom;
R 12 is a sulfo group;
The azo compound according to claim 1 or 2 or a tautomer thereof, or a salt thereof, wherein R 13 is a sulfo group.
R 1 is a methyl group;
R 2 is a cyano group;
R 3 is a methoxy group;
R 4 is a sulfo group;
R 5 is a sulfo (C1-C4) alkylthio group;
R 6 is a (C1-C4) alkylcarbonylamino group;
R 7 is a sulfo (C1-C4) alkylthio group;
R 8 is a (C1-C4) alkylcarbonylamino group;
R 9 is a sulfo (C1-C4) alkoxy group;
R 10 is a chlorine atom;
R 11 is a hydrogen atom;
R 12 is a chlorine atom;
The azo compound according to claim 1 or 2 or a tautomer thereof, or a salt thereof, wherein R 13 is a sulfo group.
An aqueous ink composition comprising at least one kind of the azo compound according to any one of claims 1 to 4 or a tautomer thereof, or a salt thereof as a coloring matter.
The water-based ink composition according to claim 5, further comprising a water-soluble organic solvent.
An ink jet recording method in which recording is performed on a recording material by using the water-based ink composition according to claim 5 or 6 as ink, and discharging ink droplets of the ink according to a recording signal.
The inkjet recording method according to claim 7, wherein the recording material is an information transmission sheet.
The inkjet recording method according to claim 8, wherein the information transmission sheet is a sheet having an ink receiving layer containing a porous white inorganic substance.
An inkjet printer loaded with a container containing the water-based ink composition according to claim 5 or 6.
a) the azo compound according to any one of claims 1 to 4 or a tautomer thereof, or a salt thereof;
b) the water-based ink composition according to claim 5 or 6, and
c) A colored body colored by any one of the ink jet recording method according to claim 7.