JP2013249319A - Azo compound, ink composition, recording method, and colored material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: an azo compound that has high solubility to a medium including water as a major component, is stable even when a concentrated aqueous solution and ink are preserved for a long period of time, and provides an achromatic color, high-quality and black color recorded image, wherein a printing density is high, and color rendering properties are excellent; and to provide an ink composition including the compound.SOLUTION: An azo compound shown by formula (1), a tautomer of the same or salts of the same are disclosed. In the formula, Rdenotes a C1-C4 alkyl group or the like; Rdenotes a cyano group or the like; Rand Reach independently denote a hydrogen atom, a sulfo group, a methoxy group or the like; Rand Rdenote a C1-C4 alkoxy group or the like; Rdenotes a C1-C4 alkylthio group or the like; Rdenotes an acetylamino group or the like; Rand Rdenote a C1-C4 alkoxy group or the like; and Rto Reach independently denote a hydrogen atom, a sulfo group or the like.

Description

  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 product 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. In addition, due to the feature of being easy to downsize 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. With these inks, it is possible to provide a recording image with sufficient density, no clogging of the pen tip and nozzles, good drying on the recording material, less bleeding, and storage stability. It is required to be excellent. In addition, the water-soluble dye used is required to have a particularly high solubility in water and a high solubility in a 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 paper or in the recording paper to discolor the recorded image. . 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 exclusive inkjet paper capable of obtaining photographic image quality in order to expedite ink drying and to 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.

  In the future, in order to expand the field of use of ink jet recording, further improvement in light resistance, gas resistance, moisture resistance, water resistance and the like is strongly demanded for ink jet recorded images. In addition to this, a black image is required to have a low color rendering property. 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 and 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 Documents 7 and 8 and Non-Patent Document 1 disclose these methods.

  Various hue inks are prepared from various pigments, of which 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 demands of the market. 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 safety and environmental issues for living organisms, and have extremely high gas resistance. There are problems such as weakness.

  As a black compound (black pigment) for ink jet recording improved with respect to gas resistance, which has become the most important issue in recent years, for example, the 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 2 to 6 and the like. Patent Document 3 discloses trisazo compounds, but these trisazo compounds have a symmetrical structure in which two benzimidazolopyridone skeletons are further bonded to each end of a linking group containing an azo structure by an azo structure. Nothing similar to the asymmetric azo compound of the present invention is disclosed. Patent Documents 4 and 5 disclose that a trisazo compound and a water-soluble black compound are used for inkjet recording. Patent Document 6 discloses 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 German Patent No. 2000004488 International Publication No. 2007/077931 International Publication No. 2009/069279 JP 2008-169374 A Japanese Patent Laid-Open No. 01-284562 Japanese Patent Publication No. 05-018955 Processing Technology Vol. 31, No. 9, 1996, 599-602

  The present invention, when recorded on inkjet paper, has excellent (ozone) gas resistance, very high print density, low color rendering, low saturation, and a high-quality black dye, and An object of the present invention is to provide an ink composition containing the coloring matter, 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.

［式（１）中、
Ｒ¹は、（Ｃ１〜Ｃ４）アルキル基；カルボキシ基で置換された（Ｃ１〜Ｃ４）アルキル基；フェニル基；スルホ基で置換されたフェニル基；又は、カルボキシ基；を表し、
Ｒ²はシアノ基；カルバモイル基；又は、カルボキシ基；を表し、
Ｒ³及びＲ⁴は、それぞれ独立して、水素原子；（Ｃ１〜Ｃ４）アルキル基；ハロゲン原子；（Ｃ１〜Ｃ４）アルコキシ基；又は、スルホ基；を表し、
Ｒ⁵及びＲ⁶は、それぞれ独立して、水素原子；カルボキシ基；スルホ基；アセチルアミノ基；塩素原子；（Ｃ１〜Ｃ４）アルキル基；（Ｃ１〜Ｃ４）アルコキシ基；ヒドロキシ基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基およびカルボキシ基よりなる群から選択される少なくとも１種類の基で置換された（Ｃ１〜Ｃ４）アルコキシ基；を表し、
Ｒ⁷は、（Ｃ１〜Ｃ４）アルキルチオ基；ヒドロキシ基、スルホ基およびカルボキシ基よりなる群から選択される少なくとも１種類の基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；を表し、
Ｒ⁸は、（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；を表し、
Ｒ⁹及びＲ¹⁰は、それぞれ独立して、水素原子；カルボキシ基；スルホ基；アセチルアミノ基；塩素原子；（Ｃ１〜Ｃ４）アルキル基；（Ｃ１〜Ｃ４）アルコキシ基；ヒドロキシ基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基およびカルボキシ基よりなる群から選択される少なくとも１種類の基で置換された（Ｃ１〜Ｃ４）アルコキシ基；を表し、
Ｒ¹¹からＲ¹³は、それぞれ独立して、水素原子；カルボキシ基；スルホ基；ヒドロキシ基；アセチルアミノ基；塩素原子；シアノ基；ニトロ基；スルファモイル基；（Ｃ１〜Ｃ４）アルキル基；（Ｃ１〜Ｃ４）アルコキシ基；ヒドロキシ基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基およびカルボキシ基よりなる群から選択される少なくとも１種類の基で置換された（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキルスルホニル基；ヒドロキシ基、スルホ基およびカルボキシ基よりなる群から選択される少なくとも１種類の基で置換された（Ｃ１〜Ｃ４）アルキルスルホニル基；を表す。］
２）
下記式（２）で表されるアゾ化合物若しくはその互変異性体、又はそれらの塩、

［式（２）中、
Ｒ¹からＲ¹³は、前記式（１）におけるものと同じ意味を表す。]
３）
上記式（１）又は（２）において、Ｒ¹¹からＲ¹³の少なくともひとつがスルホ基；またはカルボキシ基；であり、Ｒ⁵からＲ¹⁰の少なくともひとつがスルホ基またはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；またはスルホ（Ｃ１〜Ｃ４）アルコキシ基；である上記１）又は２）に記載のアゾ化合物若しくはその互変異性体、又はそれらの塩、
４）
上記式（１）又は（２）において、Ｒ⁵及びＲ⁹がスルホ（Ｃ１〜Ｃ４）アルコキシ基；であり、Ｒ⁷がスルホ基またはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；である上記１）乃至３）のいずれか一項に記載のアゾ化合物若しくはその互変異性体、又はそれらの塩、
５）
上記式（１）又は（２）において、Ｒ¹がメチル基；またはフェニル基；、Ｒ²がシアノ基；またはカルバモイル基；、Ｒ³が水素原子；、メチル基；またはメトキシ基；、Ｒ⁴がスルホ基；である上記１）乃至４）のいずれか一項に記載のアゾ化合物若しくはその互変異性体、又はそれらの塩、
６）
上記式（１）又は（２）において、
Ｒ¹がメチル基；またはフェニル基；、
Ｒ²がシアノ基；またはカルバモイル基；、
Ｒ³が水素原子；、メチル基；またはメトキシ基；、
Ｒ⁴がスルホ基；、
Ｒ⁵がスルホ（Ｃ１〜Ｃ４）アルコキシ基；、
Ｒ⁶が（Ｃ１〜Ｃ４）アルキル基；、またはアセチルアミノ基；、または塩素原子；、
Ｒ⁷がスルホ基またはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；、
Ｒ⁸が（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；、
Ｒ⁹がスルホ（Ｃ１〜Ｃ４）アルコキシ基；、
Ｒ¹⁰が（Ｃ１〜Ｃ４）アルキル基；、またはアセチルアミノ基；、または塩素原子；、
Ｒ¹¹からＲ¹³が、それぞれ独立に、水素原子；カルボキシ基；スルホ基；塩素原子；ニトロ基；メチル基；メトキシ基；スルファモイル基；スルホ基またはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルスルホニル基；である、上記１）又は２）に記載のアゾ化合物若しくはその互変異性体、又はそれらの塩、
７）
上記式（１）又は（２）において、
Ｒ¹がメチル基；、
Ｒ²がシアノ基またはカルバモイル基；、
Ｒ³が水素原子；、メチル基；またはメトキシ基；、
Ｒ⁴がスルホ基；、
Ｒ⁵がスルホ（Ｃ１〜Ｃ４）アルコキシ基；、
Ｒ⁶が（Ｃ１〜Ｃ４）アルキル基；、またはアセチルアミノ基；、または塩素原子；、
Ｒ⁷がスルホ（Ｃ１〜Ｃ４）アルキルチオ基；、
Ｒ⁸が（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；、
Ｒ⁹がスルホ（Ｃ１〜Ｃ４）アルコキシ基；、
Ｒ¹⁰が（Ｃ１〜Ｃ４）アルキル基；、またはアセチルアミノ基；、または塩素原子；、
Ｒ¹¹からＲ¹³が、それぞれ独立に、水素原子；カルボキシ基；スルホ基；塩素原子；ニトロ基；メチル基；メトキシ基；スルファモイル基；である、上記１）又は２）に記載のアゾ化合物若しくはその互変異性体、又はそれらの塩、
８）
上記式（１）又は（２）において、Ｒ¹がメチル基；、
Ｒ²がシアノ基；、
Ｒ³が水素原子；、またはメトキシ基；、
Ｒ⁴がスルホ基；、
Ｒ⁵がスルホプロポキシ基；、
Ｒ⁶が塩素原子；、
Ｒ⁷がスルホ（Ｃ１〜Ｃ４）アルキルチオ基；、
Ｒ⁸がアセチルアミノ基；、
Ｒ⁹がスルホプロポキシ基；、
Ｒ¹⁰が（Ｃ１〜Ｃ４）アルキル基；、
Ｒ¹¹が水素原子；又はスルホ基；、
Ｒ¹²がスルホ基；、又は塩素原子；、
Ｒ¹³が水素原子；、である、上記１）又は２）に記載のアゾ化合物若しくはその互変異性体、又はそれらの塩、
９）
上記１）乃至８）のいずれか一項に記載のアゾ化合物若しくはその互変異性体、又はそれらの塩を、色素として少なくとも１種類含有する水性インク組成物、
１０）
水溶性有機溶剤をさらに含有する上記９）に記載の水性インク組成物、
１１）
上記９）又は１０）に記載のインク組成物をインクとして用い、該インクのインク滴を記録信号に応じて吐出させて被記録材に記録を行うインクジェット記録方法、
１２）
被記録材が情報伝達用シートである上記１１）に記載のインクジェット記録方法、
１３）
情報伝達用シートが多孔性白色無機物を含有するインク受容層を有するシ−トである上記１２）に記載のインクジェット記録方法、
１４）
上記９）又は１０）に記載のインク組成物を含む容器を装填したインクジェットプリンタ、
１５）
ａ）請求項１乃至８のいずれか一項に記載のアゾ化合物若しくはその互変異性体、又はそれらの塩、
ｂ）請求項９又は１０に記載の水性インク組成物、又は、
ｃ）請求項１１に記載のインクジェット記録方法、の３者のいずれかによって着色された着色体、
に関する。 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; a (C1-C4) alkyl group substituted with a carboxy group; a phenyl group; a phenyl group substituted with a sulfo group; or a carboxy group;
R ² represents a cyano group; a carbamoyl group; or a carboxy group;
R ³ and R ⁴ each independently represent a hydrogen atom; a (C1-C4) alkyl group; a halogen atom; a (C1-C4) alkoxy group; or a sulfo group;
R ⁵ and R ⁶ are each independently a hydrogen atom; a carboxy group; a sulfo group; an acetylamino group; a chlorine atom; a (C1-C4) alkyl group; a (C1-C4) alkoxy group; a hydroxy group; C4) an (C1-C4) alkoxy group substituted with at least one group selected from the group consisting of an alkoxy group, a sulfo group and a carboxy group;
R ⁷ represents a (C1-C4) alkylthio group; 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 and R ¹⁰ are each independently a hydrogen atom; a carboxy group; a sulfo group; an acetylamino group; a chlorine atom; a (C1-C4) alkyl group; a (C1-C4) alkoxy group; a hydroxy group; C4) an (C1-C4) alkoxy group substituted with at least one group selected from the group consisting of an alkoxy group, a sulfo group and a carboxy group;
R ¹¹ to R ¹³ are each independently hydrogen atom; carboxy group; sulfo group; hydroxy group; acetylamino group; chlorine atom; cyano group; nitro group; sulfamoyl group; (C1-C4) alkyl group; -C4) alkoxy group; (C1-C4) alkoxy group substituted by at least one group selected from the group consisting of hydroxy group, (C1-C4) alkoxy group, sulfo group and carboxy group; (C1-C4) An alkylsulfonyl group; a (C1 to C4) alkylsulfonyl group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group. ]
2)
An azo compound represented by the following formula (2) or a tautomer thereof, or a salt thereof;

[In Formula (2),
R ¹ to R ¹³ represent the same meaning as in formula (1). ]
3)
In the above formula (1) or (2), at least one of R ¹¹ to R ¹³ is a sulfo group; or a carboxy group; and at least one of R ⁵ to R ¹⁰ is substituted with a sulfo group or a carboxy group (C1 -C4) alkylthio group; or sulfo (C1-C4) alkoxy group; the azo compound or tautomer thereof according to 1) or 2) above, or a salt thereof,
4)
In the above formula (1) or (2), R ⁵ and R ⁹ are sulfo (C1-C4) alkoxy groups; and R ⁷ is a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group; The azo compound according to any one of 1) to 3) or a tautomer thereof, or a salt thereof,
5)
In the above formula (1) or (2), R ¹ is a methyl group; or a phenyl group;, R ² is a cyano group; or a carbamoyl group;, R ³ is a hydrogen atom; a methyl group; or a methoxy group;, R ⁴ Wherein the azo compound according to any one of 1) to 4) above or a tautomer thereof, or a salt thereof,
6)
In the above formula (1) or (2),
R ¹ is a methyl group; or a phenyl group;
R ² is a cyano group; or a carbamoyl group;
R ³ is a hydrogen atom; a methyl group; or a methoxy group;
R ⁴ is a sulfo group;
R ⁵ is a sulfo (C1-C4) alkoxy group;
R ⁶ is a (C1-C4) alkyl group; or an acetylamino group; or a chlorine atom;
R ⁷ is substituted by a sulfo group or a carboxy group (C1 -C4) alkylthio groups;,
R ⁸ is a (C1-C4) alkylcarbonylamino group;
R ⁹ is a sulfo (C1-C4) alkoxy group;
R ¹⁰ is a (C1-C4) alkyl group; or an acetylamino group; or a chlorine atom;
R ¹¹ to R ¹³ are each independently a hydrogen atom; a carboxy group; a sulfo group; a chlorine atom; a nitro group; a methyl group; a methoxy group; a sulfamoyl group; a (C1-C4) alkyl substituted with a sulfo group or a carboxy group A sulfonyl group; the azo compound according to 1) or 2) or a tautomer thereof, or a salt thereof;
7)
In the above formula (1) or (2),
R ¹ is a methyl group;
R ² is a cyano group or a carbamoyl group;
R ³ is a hydrogen atom; a methyl group; or a methoxy group;
R ⁴ is a sulfo group;
R ⁵ is a sulfo (C1-C4) alkoxy group;
R ⁶ is a (C1-C4) alkyl group; or an acetylamino group; or a chlorine atom;
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 (C1-C4) alkyl group; or an acetylamino group; or a chlorine atom;
The azo compound according to 1) or 2) above, wherein R ¹¹ to R ¹³ are each independently a hydrogen atom; a carboxy group; a sulfo group; a chlorine atom; a nitro group; a methyl group; a methoxy group; Its tautomers, or salts thereof,
8)
In the above formula (1) or (2), 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;
R ⁵ is a sulfopropoxy group;
R ⁶ is a chlorine atom;
R ⁷ is a sulfo (C1-C4) alkylthio group;
R ⁸ is an acetylamino group;
R ⁹ is a sulfopropoxy group;
R ¹⁰ is a (C1-C4) alkyl group;
R ¹¹ is a hydrogen atom; or a sulfo group;
R ¹² is a sulfo group; or a chlorine atom;
R ¹³ is a hydrogen atom, or the azo compound or tautomer thereof according to 1) or 2) above, or a salt thereof,
9)
An aqueous ink composition containing at least one kind of the azo compound according to any one of 1) to 8) or a tautomer thereof, or a salt thereof;
10)
The water-based ink composition as described in 9) above, further containing a water-soluble organic solvent,
11)
An ink jet recording method for recording on a recording material by using the ink composition according to 9) or 10) as an ink, and discharging ink droplets of the ink according to a recording signal;
12)
The inkjet recording method according to 11) above, wherein the recording material is an information transmission sheet,
13)
The inkjet recording method according to 12) above, wherein the information transmission sheet is a sheet having an ink receiving layer containing a porous white inorganic substance,
14)
An inkjet printer loaded with a container containing the ink composition according to 9) or 10) above,
15)
a) The azo compound according to any one of claims 1 to 8, or a tautomer thereof, or a salt thereof,
b) The aqueous ink composition according to claim 9 or 10, or
c) A colored product colored by any one of the three methods of the inkjet recording method according to claim 11;
About.

  The azo compound of the present invention or a salt thereof, and an ink composition containing the azo compound are suitably used as an ink for ink jet recording, and when recorded on ink jet dedicated paper, the print density is very high and the color rendering property is low. In addition, the ink composition containing the azo compound of the present invention is extremely useful as a black ink for inkjet recording because it has a low-saturation, high-quality black hue, and excellent (ozone) gas resistance. .

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.

The azo compound of the present invention represented by the formula (1) has a tautomer, and the tautomer includes the following formulas (3) and (4) in addition to the compound represented by the formula (1). Etc. are considered. These compounds are also included in the present invention. In formulas (3) and (4), R ^{1 to} R ¹³ have the same meaning as in formula (1) above.

In the above formula (1), examples of the (C1 to C4) alkyl group in R ¹ include linear or branched unsubstituted groups, and linear ones are preferable. Specific examples thereof include, for example, a linear group such as a methyl group, an ethyl group, an n-propyl group, and an n-butyl group; a branched chain such as an isopropyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group; Is mentioned. Preferable specific examples include a methyl group and an n-propyl group, and a methyl group is particularly preferable.

Examples of the (C1 to C4) alkyl group substituted with a carboxy group in R ¹ include those in which any carbon atom of the unsubstituted (C1 to 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.

Examples of the phenyl group substituted with a sulfo group in R ¹ include a phenyl group having 1 to 3, preferably 1 or 2 substituted sulfo groups, and the substitution position of the sulfo group is not particularly limited. Specific examples include 3-sulfophenyl group, 4-sulfophenyl group, 2,4-disulfophenyl group, 3,5-disulfophenyl group and the like. A preferred specific example is a 4-sulfophenyl group.

Preferable R ¹ includes a (C1 to C4) alkyl group, a (C1 to C4) alkyl group substituted with a carboxy group, a phenyl group, or a phenyl group substituted with a sulfo group.
More preferably, it is a (C1-C4) alkyl group, a phenyl group, or a phenyl group substituted with a sulfo group, and more preferably a (C1-C4) alkyl group or a phenyl group,
Particularly preferred is a (C1-C4) alkyl group, with a methyl group being most preferred.

In the above formula (1), R ² represents a cyano group; a carbamoyl group; or a carboxy group. A cyano group or a carbamoyl group is preferable, and a cyano group is more preferable.

In the above formula (1), examples of the (C1 to C4) alkyl group in R ³ and R ⁴ include the same as the (C1 to C4) alkyl group in R ¹ and preferable ones.

For R ³ or R ^4, the halogen atom, fluorine atom, chlorine atom, bromine atom, or iodine atom and the like, a chlorine atom is preferable.

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 a straight chain such as a methoxy group, an ethoxy group, an n-propoxy group, and an n-butoxy group; a branched chain such as an isopropoxy group, an isobutoxy group, a sec-butoxy group, and a tert-butoxy group; Can be mentioned. Of these, a methoxy group is particularly preferred.

R ³ and R ⁴ are each independently preferably a hydrogen atom, a (C1-C4) alkyl group, a (C1-C4) alkoxy group, or a sulfo group.
More preferably, one is a combination of hydrogen atoms and the other is a sulfo group.
The substitution position of R ³ and R ⁴ is not particularly limited. When either one is a hydrogen atom and the other is a sulfo group, the sulfo group is not adjacent to any nitrogen atom constituting the benzimidazolopyridone ring. It is preferable to substitute one of the two carbon atoms.

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 preferable combination of R ^{1 to} R ⁴ in the formula (1), R ¹ is a (C1-C4) alkyl group or a phenyl group (preferably a (C1-C4) alkyl group, more preferably a methyl group), and R ² is Examples include a combination of a cyano group or a carbamoyl group (preferably a cyano group), R ³ is a hydrogen atom, a methyl group, a methoxy group (preferably a methoxy group), and R ⁴ is a sulfo group.

In the above formula (1), examples of the (C1 to C4) alkyl group in R ⁵ and R ⁶ include the same as the (C1 to C4) alkyl group in R ¹ and preferable ones.

Examples of the (C1 to C4) alkoxy group in R ⁵ and R ⁶ include the same groups as the (C1 to C4) alkoxy group in R ³ and R ⁴ , including preferable ones.

(C1-C4) alkoxy group substituted with at least one group selected from the group consisting of a hydroxy group, a (C1-C4) alkoxy group, a sulfo group, and a carboxy group as a substituent in R ⁵ and R ⁶ Examples thereof include those having these substituents on 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 thereof include, for example, 2-hydroxyethoxy group, 2-hydroxypropoxy group, 3-hydroxypropoxy group, hydroxy (C1-C4) alkoxy group; 2-sulfoethoxy group, 3-sulfopropoxy group, 4-sulfo And a sulfo (C1 to C4) alkoxy group such as a butoxy group; a carboxy (C1 to C4) alkoxy group such as a 2-carboxyethoxy group, a 3-carboxypropoxy group, and a 4-carboxybutoxy group.

Among the above, preferable R ⁵ includes a sulfo (C1 to C4) alkoxy group and a carboxy (C1 to C4) alkoxy group, a sulfo (C1 to C4) alkoxy group is more preferable, and a sulfopropoxy group is particularly preferable.

Among the above, preferable R ⁶ includes (C1 to C4) alkyl group, (C1 to C4) alkoxy group, sulfo (C1 to C4) alkoxy group and carboxy (C1 to C4) alkoxy group, acetylamino group, chlorine atom (C1-C4) alkyl group and a chlorine atom are more preferable, and a chlorine atom is particularly preferable.

A preferred combination of R ⁵ and R ⁶ is that R ⁵ is a sulfo (C1-C4) alkoxy group, R ⁶ is a (C1-C4) alkyl group, R ⁵ is a sulfo (C1-C4) alkoxy group, and R ⁶ is a chlorine atom. R ⁵ is a sulfopropoxy group (particularly a 3-sulfopropoxy group is preferable), R ⁶ is a methyl group, R ⁵ is a sulfopropoxy group (particularly a 3-sulfopropoxy group is preferable), and R ⁶ is a chlorine atom. The combination of is particularly preferable.

In the above formula (1), examples of the (C1 to C4) alkylthio group for R ⁷ include a linear or branched unsubstituted alkyl group, and a linear one is preferred. Specific examples thereof include, for example, a linear chain such as a methylthio group, an ethylthio group, an n-propylthio group, and an n-butylthio group; a branched chain such as an isopropylthio group, an isobutylthio group, a sec-butylthio group, and a tert-butylthio group. Can be mentioned.

As the substituent for R ^7, the (C1 to 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 includes a (C1 to 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 thereof include, for example, 2-hydroxyethylthio group, 2-hydroxypropylthio group, 3-hydroxypropylthio group, hydroxy (C1-C4) alkylthio group; 2-sulfoethylthio group, 3-sulfopropylthio group. A sulfo (C1 to C4) alkylthio group; a 2-carboxyethylthio group, a 3-carboxypropylthio group, a 4-carboxybutylthio group, and the like; a carboxy (C1 to C4) alkylthio group;

Among the above, preferable R ⁷ includes a sulfo (C1 to C4) alkylthio group or a carboxy (C1 to C4) alkylthio group, a sulfo (C1 to C4) alkylthio group is more preferable, and a sulfopropylthio group is particularly preferable. .

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

A preferred combination of R ⁷ and R ^{8 is} a combination of R ⁷ is a sulfo (C1-C4) alkylthio group, R ⁸ is an acetylamino group, R ⁷ is a sulfopropylthio group, and R ⁸ is an acetylamino group. Particularly preferred.

In the above formula (1), examples of the (C1 to C4) alkyl group in R ⁹ and R ¹⁰ include the same ones including the (C1 to C4) alkyl group in R ¹ and preferred ones.

Examples of the (C1 to C4) alkoxy group in R ⁹ and R ¹⁰ include the same groups as the (C1 to C4) alkoxy group in R ³ and R ⁴ , including preferable ones.

(C1-C4) alkoxy group substituted with at least one kind of group selected from the group consisting of a hydroxy group, a (C1-C4) alkoxy group, a sulfo group, and a carboxy group as a substituent in R ⁹ and R ¹⁰ Examples thereof include those having these substituents on 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 thereof include, for example, 2-hydroxyethoxy group, 2-hydroxypropoxy group, 3-hydroxypropoxy group, hydroxy (C1-C4) alkoxy group; 2-sulfoethoxy group, 3-sulfopropoxy group, 4-sulfo And a sulfo (C1 to C4) alkoxy group such as a butoxy group; a carboxy (C1 to C4) alkoxy group such as a 2-carboxyethoxy group, a 3-carboxypropoxy group, and a 4-carboxybutoxy group.

Among the above, preferable R ⁹ includes a sulfo (C1 to C4) alkoxy group and a carboxy (C1 to C4) alkoxy group, more preferably a sulfo (C1 to C4) alkoxy group, and a sulfopropoxy group and a sulfobutoxy group. Is particularly preferred.

Among the above, preferable R ¹⁰ includes (C1 to C4) alkyl group, (C1 to C4) alkoxy group, sulfo (C1 to C4) alkoxy group, carboxy (C1 to C4) alkoxy group, and acetylamino group. , A (C1-C4) alkyl group is more preferred, and a methyl group is particularly preferred.

A preferred combination of R ⁹ and R ^{10 is} a combination in which R ⁹ is a sulfo (C1-C4) alkoxy group, R ¹⁰ is a (C1-C4) alkyl group, and R ⁹ is a sulfopropoxy group (particularly a 3-sulfopropoxy group). R ¹⁰ is a methyl group, R ⁹ is a sulfobutoxy group (particularly a 4-sulfobutoxy group is particularly preferable), and R ¹⁰ is a methyl group.

In the above formula (1), examples of the (C1 to C4) alkyl group in R ¹¹ to R ¹³ include the same ones including the (C1 to C4) alkyl group in R ¹ and preferred ones.

Examples of the (C1 to C4) alkoxy group in R ¹¹ to R ¹³ include the same groups as the (C1 to C4) alkoxy group in R ³ and R ⁴ , including preferable ones.

As a substituent in R ¹¹ to R ¹³ , (C 1 -C 4) alkoxy substituted with at least one group selected from the group consisting of a hydroxy group, a (C 1 -C 4) alkoxy group, a sulfo group, and a carboxy group The group is substituted with at least one group selected from the group consisting of a hydroxy group, a (C1 to C4) alkoxy group, a sulfo group, and a carboxy group as a substituent in the above R ⁵ and R ⁶ (C1 -C4) The same thing is included including an alkoxy group and a preferable thing.

Examples of the (C1 to C4) alkylsulfonyl group in R ¹¹ to R ¹³ include linear or branched ones, and linear ones are preferred. Specific examples include a straight chain such as a methylsulfonyl group, an ethylsulfonyl group, an n-propylsulfonyl group, and an n-butylsulfonyl group; a branched chain such as an isopropylsulfonyl group and an isobutylsulfonyl group; Among the above, a methylsulfonyl group, an ethylsulfonyl group, and an isopropylsulfonyl group are preferable, and a methylsulfonyl group is particularly preferable.

As the substituent in R ¹¹ to R ¹³ , the (C1 to C4) alkylsulfonyl group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group and a carboxy group includes the above (C1 to C1). C4) The above-mentioned groups are substituted on any carbon atom in the alkylsulfonyl group, and the number of the substituents is usually 1 or 2, preferably 1. The position of the substituent is not particularly limited. Specific examples include hydroxy-substituted groups such as hydroxyethylsulfonyl group and 2-hydroxypropylsulfonyl group; sulfo-substituted groups such as 2-sulfoethylsulfonyl group and 3-sulfopropylsulfonyl group; 2-carboxyethylsulfonyl group; Carboxy-substituted ones such as 3-carboxypropylsulfonyl group; and the like.

Among the above, preferable R ¹¹ includes a hydrogen atom, a carboxy group, a sulfo group, a nitro group, a chlorine atom, a methyl group, a methoxy group, and a (C1 to C4) alkylsulfonyl group, and a hydrogen atom, a carboxy group, a sulfo group. Group, nitro group, methyl group, methoxy group and chlorine atom are more preferred, and hydrogen atom and chlorine atom are particularly preferred.

Among the above, preferable R ¹² is a hydrogen atom, a carboxy group, a sulfo group, a nitro group, a chlorine atom, a methyl group, a methoxy group, a sulfamoyl group, a (C1 to C4) alkylsulfonyl group, or a carboxy (C1 to C4) alkyl. Examples include a sulfonyl group and a sulfo (C1 to C4) alkylsulfonyl group, and a sulfo group, a nitro group, a methyl group, a methoxy group, a sulfamoyl group, a sulfopropylsulfonyl group, and a carboxyethylsulfonyl group are more preferable, and a sulfo group is particularly preferable.

Among the above, preferable R ¹³ includes a hydrogen atom, a carboxy group, a sulfo group, a methoxy group, a nitro group, a chlorine atom, and a (C1 to C4) alkylsulfonyl group, and a hydrogen atom, a sulfo group, and a methoxy group are more preferable. Preferably, a hydrogen atom is particularly preferable.

A preferred combination of R ¹¹ to R ^{13 is} a combination of R ¹¹ as a hydrogen atom, R ¹² as a sulfo group, R ¹³ as a hydrogen atom, R ¹¹ as a hydrogen atom, R ¹² as a sulfamoyl group, and R ¹³ as a hydrogen atom, Or a combination of R ¹¹ is a hydrogen atom, R ¹² is a chlorine atom, R ¹³ is a sulfo group, R ¹¹ is a hydrogen atom, R ¹² is a chlorine atom, and R ¹³ is a sulfo group is particularly preferable.

  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 still more preferable. The same applies to preferable combinations, preferable combinations, and more preferable combinations.

  A more preferred compound of the above formula (1) is a compound represented by the above formula (2).

In the above formula (2), R ^{1 to} R ¹⁰ represent the same meaning as in the above formula (1), and preferred groups and preferred combinations of groups are the same as in the above formula (1), and the above R ^{5 to} R More preferably, ¹⁰ is substituted at the position of formula (2).

R ¹¹ to R ¹³ in the formula (2) represents the same meaning as R ¹¹ to R ¹³ in the formula (1), combinations of the preferred groups and preferred groups are also the same as in the formula (1).
In the formula (2), more preferable R ^{11 to} R ¹³ can specify the substitution position thereof.
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 or 3-position, R ¹² is 4-position, and R ¹³ is 5-position Alternatively, those substituted at the 6-position are preferred.
Particularly preferred in the formula (2) is one in which the substitution positions of R ^{5 to} R ¹³ are specified as described above, and the type of the substituent may be the same as in the above formula (1).

Specific examples of preferable combinations in the above formulas (1) and (2) include the following combinations (i) to (iii). (Ii) is preferable to (i), and (iii) is most preferable.
(I)
R ¹ is a methyl group; or a phenyl group;
R ² is a cyano group; or a carbamoyl group;
R ³ is a hydrogen atom; a methyl group; or a methoxy group;
R ⁴ is a sulfo group;
R ⁵ is a sulfo (C1-C4) alkoxy group;
R ⁶ is a (C1-C4) alkyl group; or an acetylamino group; or a chlorine atom,
R ⁷ is substituted by a sulfo group or a carboxy group (C1 -C4) alkylthio groups;,
R ⁸ is a (C1-C4) alkylcarbonylamino group;
R ⁹ is a sulfo (C1-C4) alkoxy group;
R ¹⁰ is a (C1-C4) alkyl group; or an acetylamino group; or a chlorine atom,
R ¹¹ to R ¹³ are each independently a hydrogen atom; a carboxy group; a sulfo group; a methyl group; a methoxy group; a chlorine atom; a nitro group; a sulfamoyl group; a (C1-C4) alkyl substituted with a sulfo group or a carboxy group A sulfonyl group;
(Ii)
R ¹ is a methyl group;
R ² is a cyano group; or a carbamoyl group;
R ³ is a hydrogen atom; a methyl group; or a methoxy group;
R ⁴ is a sulfo group;
R ⁵ is a sulfo (C1-C4) alkoxy group;
R ⁶ is a (C1-C4) alkyl group; or an acetylamino group; or a chlorine atom,
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 (C1-C4) alkyl group; or an acetylamino group; or a chlorine atom,
A combination in which R ¹¹ to R ¹³ are each independently a hydrogen atom; a sulfo group; a methyl group; a methoxy group; a chlorine atom; a nitro group;
(Iii)
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;
R ⁵ is a sulfopropoxy group;
R ⁶ is an acetylamino group; or a chlorine atom;
R ⁷ is a sulfo (C1-C4) alkylthio group;
R ⁸ is an acetylamino group;
R ⁹ is a sulfopropoxy group;
R ¹⁰ is a (C1-C4) alkyl group;
R ¹¹ is a hydrogen atom; or a sulfo group;
R ¹² is a sulfo group; or a chlorine atom;
A combination in which R ¹³ is a hydrogen atom; or a sulfo group.

The trisazo compound of the present invention represented by the above formula (1) can be synthesized, for example, by the following method. Moreover, 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 resulting 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 shown by the structural formula given to the following Table 1 thru | or 6 is mentioned.
In each table, functional groups such as sulfo group and carboxy group are described in the form of free acid for convenience.

  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 nitrous acid in an inorganic acid medium, for example, at a temperature of -5 to 30 ° C, preferably 0 to 15 ° C. It is carried out using an alkali metal nitrite such as sodium nitrate. Coupling of the diazotized compound of the compound represented by the formula (5) and the compound represented by the formula (6) 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 30 ° C, preferably 0 to 25 ° C, and at an acidic to neutral pH value, for example pH 1-6. 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 a preferable 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 Formula (5) and the compound represented by Formula (6) are used in a substantially stoichiometric amount.

  The diazotization of the compound represented by the above formula (7) is carried out by a method known per se, for example, a nitrite such as nitrous acid in an inorganic acid medium at a temperature of, for example, -5 to 40 ° C, preferably 5 to 30 ° C. It is carried out using an alkali metal nitrite such as sodium nitrate. Coupling of the diazotized compound of the compound of formula (7) with the compound of formula (8) 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 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 a preferable pH condition of the reaction liquid by adding a base. The same base as described above can be used. The compound represented by formula (7) and the compound represented by formula (8) are used in approximately stoichiometric amounts.

  The diazotization of the compound represented by the above formula (9) is carried out by a method known per se, for example, a nitrite such as nitrous acid in an inorganic acid medium, for example, at a temperature of -5 to 50 ° C, preferably 5 to 40 ° C. It is carried out using an alkali metal nitrite such as sodium nitrate. Coupling of the diazotized compound of the compound represented by formula (9) and the compound represented by 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 [deg.] C, preferably 10 to 40 [deg.] C and 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 a preferable pH condition of the reaction liquid by adding a base. The same base as described above can be used. The compound represented by formula (9) and the compound represented by formula (10) are used in approximately stoichiometric amounts.

  The diazotization of the compound of formula (11) is also carried out in a manner known per se, for example a nitrite, for example sodium nitrite, in an inorganic acid medium, for example at a temperature of -5 to 50 ° C, preferably 10 to 40 ° C. It is carried out using an alkali metal nitrite such as The coupling of the diazotized compound of the compound represented by the formula (11) and the compound represented by the formula (12) is also carried out under conditions known per se. It is advantageous to carry out the reaction in water or an aqueous organic medium, for example at a temperature of -5 to 50 ° C, preferably 10 to 40 ° C, and 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 compounds represented by formulas (11) and (12) are used in approximately stoichiometric amounts.

  The salt of the azo compound represented by the above formula (1) is a salt with an inorganic or organic cation. Among these, specific examples of inorganic salts include alkali metal salts, alkaline earth metal salts, and ammonium salts. Preferred inorganic salts are lithium, sodium, potassium, and ammonium salts. Examples of the organic cation salt include, but are not limited to, salts with quaternary ammonium ions 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. The physical properties such as solubility may vary depending on the type of salt, and the physical properties that meet the purpose can be selected by selecting the type of salt as appropriate, or by changing the ratio when multiple salts are included. It is also possible to obtain a mixture having

In the above formula (13), Z ¹ , Z ² , Z ³ and Z ⁴ each independently represent a group selected from the group consisting of a hydrogen atom, an unsubstituted alkyl group, a hydroxyalkyl group and a hydroxyalkoxyalkyl group, At least one is a group other than a hydrogen atom.
Specific examples of the alkyl group represented by Z ^{1 to} Z ⁴ in the formula (13) include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. Specific examples of the hydroxyalkyl group include hydroxymethyl group, hydroxyethyl group, 3-hydroxypropyl group, 2-hydroxypropyl group, 4-hydroxybutyl group, 3-hydroxybutyl group, 2-hydroxybutyl group, etc. Examples of the hydroxyalkoxyalkyl group include hydroxyethoxymethyl group, 2-hydroxyethoxyethyl group, 3-hydroxyethoxypropyl group, 2-hydroxyethoxypropyl group, 4-hydroxyethoxy (C1-C4) alkyl group, Hydroxyethoxybutyl group, 3-hydroxyethoxybutyl And hydroxy (C1-C4) alkoxy (C1-C4) alkyl groups such as 2-hydroxyethoxybutyl group, among which hydroxyethoxy (C1-C4) alkyl is preferred. Particularly preferred are hydrogen atoms; hydroxy such as methyl, hydroxymethyl group, hydroxyethyl group, 3-hydroxypropyl group, 2-hydroxypropyl group, 4-hydroxybutyl group, 3-hydroxybutyl group, 2-hydroxybutyl group, etc. (C1-C4) alkyl group, hydroxyethoxymethyl group, 2-hydroxyethoxyethyl group, 3-hydroxyethoxypropyl group, 2-hydroxyethoxypropyl group, 4-hydroxyethoxybutyl group, 3-hydroxyethoxybutyl group, 2- And hydroxyethoxy (C1-C4) alkyl groups such as hydroxyethoxybutyl group.

Specific examples of combinations of Z ¹ , Z ² , Z ³ , and Z ^{4 which} are preferable compounds as the formula (13) are shown in Table 7 below.

As a method for synthesizing a desired salt of the azo compound represented by the formula (1) of the present invention, after completion of the final step in the synthesis reaction of the compound represented by the formula (1), a desired inorganic salt or organic Obtained by 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 or an aqueous organic medium as necessary to remove impurities such as attached inorganic salts, and again in an 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 refers to 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 formula (1) is used as a desired salt include alkali metal halogen salts such as lithium chloride, sodium chloride and potassium chloride; lithium carbonate, sodium carbonate and potassium carbonate Alkali metal carbonates such as lithium hydroxide, sodium hydroxide, potassium hydroxide and other alkali metal hydroxides; ammonium ion halogen salts such as ammonium chloride and ammonium bromide; ammonium hydroxide (ammonia water), etc. And ammonium ion hydroxides.
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, materials having a carbonamide bond can be dyed, and 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. I can do things. However, 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 the like; A product 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 formula (1) of the present invention as a pigment. It is a water-based ink composition containing. 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. In the ink composition of the present invention, the water-soluble organic solvent is 0 to 30% by mass, preferably 5 to 30% by mass, and the ink preparation agent is 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 in terms of improving storage stability. Further, the surface tension of the ink composition is preferably 25 to 70 mN / m, and 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, black, etc. The other pigment | dye which has a hue is mentioned.

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 containing a small amount 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 less 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; or a dried product or wet cake of the azo compound of the present invention with an alcohol such as methanol, preferably (C1-C4) alcohol In addition, the mixture may be suspended and purified in a mixed solvent of water and water, and the precipitate may be desalted by a known method such as a method of separating and drying the precipitate by filtration.

  Specific examples of water-soluble organic solvents that can be used in preparing the ink composition of the present invention include (C1-C4) alcohols such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol or tert-butanol. A carboxylic acid amide such as N, N-dimethylformamide or N, N-dimethylacetamide; a lactam such as 2-pyrrolidone, hydroxyethyl-2-pyrrolidone, N-methyl-2-pyrrolidone or N-methylpyrrolidin-2-one Cyclic cyclic ureas such as 1,3-dimethylimidazolidin-2-one or 1,3-dimethylhexahydropyrimido-2-one; acetone, methyl ethyl ketone, 2-methyl-2-hydroxypentan-4-one, etc. Ketones or ketoalcohols; tetrahydrofuran, dioxa Cyclic ethers such as 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, Mono-, oligo- or polyalkylene glycols or thioglycols having C2-C6 alkylene units such as tetraethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, thiodiglycol or dithiodiglycol; trimethylolpropane, glycerin or hexane-1 , 2,6-triol and other polyols (preferably triol); ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol (C1-C4) alkyl ethers of polyhydric alcohols such as dimethyl monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether (butyl carbitol) triethylene glycol monomethyl ether or triethylene glycol monoethyl ether; γ-butyrolactone; or dimethyl Sulfoxide; and the like. 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, p-hydroxybenzoic acid ethyl ester, 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, and benzothiazole. , Isothiazoline, dithiol, pyridine oxide, nitropropane, organotin, phenol, quaternary ammonium salt, triazine, thiazine, anilide, adamantane, dithiocarbamate, brominated indanone, benzyl Examples thereof include bromoacetate-based or inorganic salt-based compounds. Specific examples of organic halogen compounds include sodium pentachlorophenol, specific examples of pyridine oxide compounds include, for example, sodium 2-pyridinethiol-1-oxide, and isothiazoline compounds include, 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 -Isothiazoline-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 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); Or alkali metal carbonates, such as lithium carbonate, sodium carbonate, sodium hydrogencarbonate, potassium carbonate; Alkali metal salts of organic acids, such as potassium acetate; Inorganic bases, such as sodium silicate and disodium phosphate, etc. are mentioned.

  Specific examples of the chelating reagent include sodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate or sodium uracil diacetate.

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

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

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

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

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

  Examples of the surfactant include known surfactants such as anionic, cationic, and nonionic surfactants. Examples of anionic surfactants include alkyl sulfonates, alkyl carboxylates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, N-acyl amino acids and salts thereof, N-acyl methyl taurate, alkyl sulfate poly Oxyalkyl 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, diethyl Examples include sulfosuccinate, diethylhexylsylsulfosuccinate, and dioctylsulfosuccinate.

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

  Examples of amphoteric surfactants include lauryldimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, coconut oil fatty acid amidopropyldimethylaminoacetic acid betaine, polyoctylpolyaminoethylglycine, or imidazoline derivatives. 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) series such as lu-1-hexyn-3-ol; trade name Surfynol 104, 105, 82, 465, Olphine STG, etc. manufactured by Nissin Chemical; Polyglycol ether series (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 to remove impurities, and when used for ink jet recording, it is preferable to perform the filtration. The pore diameter of the filter for performing microfiltration is usually 1 μm to 0.1 μm, preferably 0.8 μm 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 of performing recording by using the ink composition of the present invention as an ink, and ejecting ink droplets of the ink in accordance with a recording signal to adhere to a 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 they 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. For example, information transmission sheets such as paper and film, fibers and cloths (cellulose, nylon, wool, etc.), leather, and color filter base materials. Among them, an information transmission sheet is preferable.
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; or a porous white inorganic substance capable of absorbing a pigment in the ink, such as porous silica, alumina sol, or special ceramics. And a hydrophilic polymer such as polyvinyl pyrrolidone, and the like.
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 inkjet recording method of the present invention comprises the black ink composition of the present invention and, for example, the known magenta, cyan, yellow, and green, blue (or violet), red (or orange), etc. as necessary. 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 8) or a tautomer thereof, or a salt thereof,
b) The water-based ink composition as described in 9) or 10) above, or
c) A substance colored by any one of the three methods of the ink jet recording method described in 11) 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 with a membrane filter in the process of producing 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 is particularly excellent in ozone resistance, has a very high printing density, low color rendering, low chroma, and a high-quality black hue. Excellent fastness such as light resistance, moisture resistance and water resistance. Further, when used in combination with ink compositions containing magenta, cyan and yellow pigments, 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.
Operations such as each synthesis reaction and crystallization were performed under 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.
Moreover, 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 thereto in about 15 minutes. After the dropwise addition, the reaction solution was added to 400 parts of water after reacting at 40-50 ° C. for 2 hours. After stirring at room temperature for 30 minutes, the precipitated solid was filtered, and the obtained solid was washed with 100 parts of funnel water, separated and dried to obtain 63.0 parts of a compound represented by the following formula (14). Obtained.

(Process 2)
42.9 parts of the compound represented by the formula (14) obtained in the above (Step 1) is dissolved in 115.0 parts of N-methyl-2-pyrrolidone, and 40.9 sodium sodium 3-mercaptopropanesulfonate is dissolved therein. 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, and the solid obtained after cooling to room temperature 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, and the following formula (15 ) Was obtained as a wet cake.

(Process 3)
To 150 parts of water, 102.6 parts of a wet cake of the compound represented by the formula (15) obtained in the above (Step 2), 1.6 parts of activated carbon and 0.4 parts of anhydrous iron (III) chloride are added. After heating to 60 ° C., 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 addition of 50% sulfuric acid, and the precipitated solid was collected by filtration to obtain 62.3 parts of a compound represented by the following formula (16) as a wet cake.

(Process 4)
20.8 parts of 5-amino-2-chlorobenzenesulfonic acid was dissolved in 200 parts of water while adjusting the pH to 6 with sodium hydroxide, and then 7.2 parts of sodium nitrite was added. This solution was added dropwise at 0 to 10 ° C. in 200 parts of 5% hydrochloric acid over 30 minutes, followed by stirring at 10 ° C. or lower for 1 hour to carry out a diazotization reaction to prepare a diazo reaction solution. On the other hand, 26.6 parts of 2- (sulfopropoxy) -5-chloroaniline were dissolved in 130 parts of water while adjusting the pH to 7 with sodium hydroxide, and 10.4 parts of sodium bisulfite and 8.6 parts of 35 Using methyl formalin, a methyl-ω-sulfonic acid derivative was obtained by a conventional method. The obtained methyl-ω-sulfonic acid derivative was added to the previously prepared diazo reaction solution, and the mixture was stirred at 0 to 15 ° C. and pH 2 to 24 for 24 hours. 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, further salted out by adding 100 parts of sodium chloride, and the precipitated solid was separated by filtration. 100 parts of an azo compound represented by the formula (17) was obtained as a wet cake.

(Process 5)
After adding 85.0 parts of the wet cake of the compound represented by the formula (17) obtained in the above (Step 4) to 40 parts of water, pH 6.0 to 7.0 is added by adding a 25% aqueous sodium hydroxide solution. As an aqueous solution was obtained. After adding 24.8 parts of 35% hydrochloric acid, 9.8 parts of 40% aqueous sodium nitrite solution was added and reacted for about 30 minutes. 2.0 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 30.8 parts of the wet cake of the compound represented by the formula (16) obtained in the above (Step 3) to 250 parts of water, pH 4.0 to 5 is obtained by adding a 25% aqueous sodium hydroxide solution. Solution was obtained as 0.0. This aqueous solution was added dropwise to the diazo reaction solution obtained above in about 5 minutes. After the dropwise addition, the reaction was continued 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 90 parts of a compound represented by the following formula (18) as a wet cake.

(Step 6)
To 250 parts of water, 45 parts of a wet cake of the compound represented by the above formula (18) obtained in the above (Step 4) was added and dissolved by stirring. After adding 16.5 parts of 35% hydrochloric acid, 4.7 parts of 40% aqueous sodium nitrite solution was added and stirred for about 30 minutes. 2.0 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, 5.5 parts of a compound of the following formula (19) obtained by the method described in JP-A-2004-083492 is added to 60 parts of water, and the pH is 4.5 to 5. by adding a 25% aqueous sodium hydroxide solution. An aqueous solution was obtained as 5. This aqueous solution was added dropwise to the diazo reaction solution obtained above in about 5 minutes. After the dropwise addition, the mixture was reacted for 3 hours while maintaining the pH at 2.0 to 3.0 by adding a 15% aqueous sodium carbonate solution. After the pH was adjusted to 4.5 by adding a 15% aqueous sodium carbonate solution, 350 parts of methanol was added. The precipitated solid was collected by filtration to obtain 96.6 parts of a compound represented by the following formula (20) as a wet cake.

(Step 7)
To 170 parts of water, 32.2 parts of a wet cake of the compound represented by the formula (20) obtained in the above (Step 6) was added and dissolved by stirring. After adding 5.2 parts of 35% hydrochloric acid, 1.5 parts of 40% aqueous sodium nitrite solution was added and stirred 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, 2.2 parts of a compound represented by the following formula (21) obtained by the method described in Patent Document 4 is added to 60 parts of water, and a 25% aqueous sodium hydroxide solution is added to adjust the pH to 7.5 to 8.5. To obtain an aqueous solution. The diazo reaction liquid obtained above was dropped into this aqueous solution at 15 to 30 ° C. for about 30 minutes. At this time, an aqueous sodium carbonate solution was added to maintain the pH of the reaction solution at 7.5 to 8.5, 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 29.5 parts of a wet cake. The obtained wet cake was dissolved in 100 parts of water, the pH was adjusted to 7.0 to 7.5 with 35% hydrochloric acid, 80 parts of methanol was added, and the precipitated solid was collected by filtration. The obtained wet cake was dissolved again in 60 parts of water, and 90 parts of methanol was added. The precipitated solid was separated by filtration and dried to obtain 6.3 parts of a compound represented by the following formula (22) of the present invention as a sodium salt (λmax: 582 nm).

[Example 2]
A sodium salt of 6.3 parts of the compound represented by the above formula (22) obtained in Example 1 and 14 parts of lithium chloride were added to 140 parts of water and stirred to obtain an aqueous solution. 400 parts of 2-propanol was added and the precipitated solid was separated by filtration to obtain a wet cake. The obtained wet cake and 12.5 parts of lithium chloride were again added to 150 parts of water and stirred to obtain an aqueous solution. 350 parts of 2-propanol was added and the precipitated solid was separated by filtration to obtain a wet cake. The obtained wet cake was dissolved in 80 parts of water, 150 parts of 2-propanol was added, and the precipitated solid was separated by filtration to obtain a wet cake. The wet cake obtained again was dissolved in 40 parts of water, 100 parts of 2-propanol was added, the precipitated solid was separated by filtration, and dried to obtain compound 4.5 represented by the above formula (22) of the present invention. Part was obtained as a mixed salt of sodium and lithium.

[Example 3]
(Process 1)
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 reaction was carried out at 20 ° C. to 30 ° C. under a hydrogen pressure of 0.2 MPa-0.5 MPa until there was no hydrogen absorption. 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 (23).

(Process 2)
To 200 parts of the solution containing the compound represented by the formula (23) obtained in Example 3 (Step 1), 13.0 parts of methyl cyanoacetate was added and refluxed for 30 minutes. 100 parts, then sodium carbonate was 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 (24).

(Process 3)
8.3 parts of the compound represented by the above formula (24), 12.0 parts of 28% sodium methoxide and 7.2 parts of methyl acetoacetate were added to 100 parts of ethanol and refluxed for 30 minutes, and then 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 11.1 parts of a compound represented by the following formula (25). It was. The obtained compound represented by the following formula (25) was a mixture of compounds in which a methoxy group was substituted with b or c.

(Process 4)
After slowly adding 5.6 parts of the compound represented by the above formula (25) at 5 to 10 ° C. in 77 parts of 8% fuming sulfuric acid, the mixture was reacted at the same temperature for 1.5 hours. The reaction solution was dropped into 150 parts of ice water in about 10 minutes, stirred at 65 to 70 ° C. for 30 minutes, and then the precipitated solid was filtered and separated to obtain a wet compound of the following formula (26). 24.4 parts of cake were obtained. In the compound represented by the following formula (26), 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, It was a mixture of compounds in which the substitution position was a, b or d.

(Process 5)
In Example 1 (Step 7), instead of using 2.2 parts of the compound represented by Formula (21), wet the compound represented by Formula (26) obtained in Example 3 (Step 4). Except for using 7.2 parts of cake, 6.3 parts of a compound represented by the following formula (27) of the present invention was obtained as a sodium salt. In the obtained dye, the methoxy group in the following formula (27) is at the position b, the substitution position of the sulfo group is a, c or d, or the methoxy group is at the position c, It was a mixed dye composed of 2 to 6 compounds having a substitution position of a, b or d (λmax: 586 nm).

[Example 4]
In Example 2 above, instead of using 6.3 parts of the sodium salt of the compound represented by Formula (22), sodium of the compound represented by Formula (27) obtained in Example 3 (Step 5) above Except for using 8.8 parts of the salt, 4.5 parts of the compound represented by the above formula (27) of the present invention was obtained as a mixed salt of sodium and lithium.

[Example 5]
(Process 1)
15.2 parts of 2-methyl-6-nitroaniline were dissolved in 300 parts of methanol. The obtained solution was transferred into an autoclave, 2.0 parts of 5% Pd / carbon was added, and under stirring, under hydrogen pressure of 0.2 MPa-0.5 MPa at 20 ° C. to 30 ° C. until no hydrogen was absorbed. After the reaction, 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 (28).

(Process 2)
After adding 13.0 parts of the compound represented by the formula (29) to 200 parts of the solution containing the compound represented by the above formula (28) and refluxing for 30 minutes with stirring, the reaction liquid was concentrated under reduced pressure, and 150 parts of water was added. Then, sodium carbonate was added to adjust the pH to 7.0 to 7.5. The precipitated solid was separated by filtration and dried to obtain 8.4 parts of a compound represented by the following formula (30).
The compound represented by the following formula (29) was obtained by the method described in Patent Document 11.

(Process 3)
8.4 parts of the compound represented by the above formula (30), 12.3 parts of 28% sodium methoxide and then 7.4 parts of methyl acetoacetate were added to 100 parts of ethanol and refluxed for 30 minutes. 150 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 10.0 parts of a compound represented by the following formula (31). It was. The compound represented by the following formula (31) was a compound in which a methyl group was substituted at the position a or d.

(Process 4)
After slowly adding 5.0 parts of the compound represented by the above formula (31) at 5 to 10 ° C. in 102 parts of 3% fuming sulfuric acid, the mixture was stirred at the same temperature for 1 hour. The reaction solution was dropped into 240 parts of ice water in about 10 minutes, and the precipitated solid was separated by filtration to obtain 14.7 parts of a wet cake containing a compound represented by the following formula (32). In the compound represented by the following formula (32), the methyl group is at position a and the sulfo group substitution position is c, or the methyl group is at d position and the sulfo group substitution position is b. It was one of the compounds.

(Process 5)
In Example 1 (Step 7), instead of using 2.2 parts of the compound represented by Formula (21), the wetness of the compound represented by Formula (32) obtained in Example 5 (Step 4) was used. Except for using 6.0 parts of cake, 6.0 parts of the compound represented by the following formula (33) of the present invention was obtained as a sodium salt. In the obtained dye, the methoxy group in the following formula (33) is at the position b, the substitution position of the sulfo group is a, c or d, or the methoxy group is at the position c, It was a mixed dye composed of 2 to 6 compounds whose substitution positions were a, b or d.

  The dyes obtained in Examples 1 to 5 were dissolved in ion-exchanged water to prepare solutions in which 5% of the dye was dissolved in water. The obtained solution was put in a sealed container and allowed to stand for 1 week in a thermostatic oven at 60 ° C., but no decomposition of the pigment occurred.

[(A) Preparation of ink]
Each dye obtained in Examples 2, 4, and 5 was mixed with each component shown in Table 8 below to obtain a black ink composition of the present invention, and then mixed with a 0.45 μm membrane filter. The product was separated by filtration, and the resulting inks were designated as Examples 6 to 8, respectively. The obtained ink composition is hereinafter referred to as “ink”.
The water used was ion exchange water. At the time of ink preparation, the pH of the ink was adjusted to pH 7-9 with lithium hydroxide, and then ion-exchanged water was added to make the total amount 100 parts. In addition, Nissin Chemical Co., Ltd. brand name Surfinol 104PG50 was used for the surfactant in the following Table 11.

[Comparative Example 1]
As a black pigment to be compared, a pigment represented by the following formula (34) was used, and an ink for comparison was prepared by the method described in (B) Preparation of ink. The following various tests conducted using this ink are referred to as Comparative Example 1. The compound represented by the following formula (34) is the compound (22) described in Example 1 of JP-A-2008-169374, and was obtained by following the methods described in the literature.

[Comparative Example 2]
As a black pigment to be compared, a pigment represented by the following formula (35) was used, and an ink for comparison was prepared by the method described in (B) Preparation of ink. The following various tests conducted using this ink are referred to as Comparative Example 2. In addition, the compound represented by the following formula (35) is the compound (28) described in Example 5 of JP-A-2008-169374, and was obtained by following the methods described in the literature.

[(C) Inkjet recording]
Using the ink obtained above, inkjet recording was performed on glossy papers 1 and 2 below using a Canon inkjet printer, product name PIXUS iP4500.
Glossy paper 1: Glossy paper manufactured by Canon, trade name Photo paper Glossy gold [GL-101A450]
Glossy paper 2: Glossy paper manufactured by Fuji Film Co., Ltd. Product name Photo finishing PRO [WPA430PRO]
When printing, create an image pattern so that six levels of gradations of 100%, 80%, 60%, 40%, 20%, 10% density can be obtained. The following evaluation test was carried out using this as a test piece.

[(D) Evaluation of recorded image]
Each recorded image obtained using the inks of Examples 6 to 8 and Comparative Examples 1 and 2 was evaluated by measuring the color difference between the images before and after the test.
The density change of the recorded image is measured by measuring the gradation portion where the reflection density Dk value of the recorded image before the test is closest to 1.0, using a colorimeter manufactured by GRETAG-MACBETH, product name SpectroEye. did. In the color measurement, all were performed under the conditions of DIN, viewing angle 2 °, and light source D65 based on the density standard. In this test, in all the test pieces, the 60% density gradation portion was a portion where the reflection density Dk value was close to 1.0.
The specific test method is as follows.

[(E) Ozone resistance test]
Each recorded image obtained by using the inks of Examples 6 to 8 and Comparative Examples 1 and 2 was naturally dried for 24 hours after printing, and using an ozone weatherometer manufactured by Suga Test Instruments Co., Ltd. Each test piece was allowed to stand for 8 hours under the conditions of ozone concentration of 40 ppm, humidity of 60% RH, and temperature of 24 ° C.
After the test was completed, color measurement was performed using the above colorimeter, and the color difference (ΔE) before and after the test was measured. The smaller the obtained color difference ΔE means that there is less discoloration due to ozone, indicating that the ozone resistance is excellent.
In the following calculation formulas, ΔL *, Δa *, and Δb * mean differences between L *, a *, and b * before and after exposure, respectively.

ΔE = (ΔL * ² + Δa * ² + Δb * ² ) ^1/2

The results are shown in Table 9 below.

A: The value of ΔE is 9.0 or less.
A: The value of ΔE is 9.0 or more and less than 11.0.
Δ: After ΔE is 11.0 or more and less than 13.0.
X: The value of ΔE is 13.0 or more.

  As is clear from the results in Table 9, it was revealed that the inks of the respective examples were extremely excellent in ozone resistance as compared with the inks of Comparative Examples 1 and 2. That is, the color difference (ΔE) after the ozone resistance test is extremely small, indicating that there is little fading due to ozone. It is also clear that high-quality recorded images can be obtained with media without a significant decrease in fastness.

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

Claims (15)

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; a (C1-C4) alkyl group substituted with a carboxy group; a phenyl group; a phenyl group substituted with a sulfo group; or a carboxy group;
R ² represents a cyano group; a carbamoyl group; or a carboxy group;
R ³ and R ⁴ each independently represent a hydrogen atom; a (C1-C4) alkyl group; a halogen atom; a (C1-C4) alkoxy group; or a sulfo group;
R ⁵ and R ⁶ are each independently a hydrogen atom; a carboxy group; a sulfo group; an acetylamino group; a chlorine atom; a (C1-C4) alkyl group; a (C1-C4) alkoxy group; a hydroxy group; C4) an (C1-C4) alkoxy group substituted with at least one group selected from the group consisting of an alkoxy group, a sulfo group and a carboxy group;
R ⁷ represents a (C1-C4) alkylthio group; 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 and R ¹⁰ are each independently a hydrogen atom; a carboxy group; a sulfo group; an acetylamino group; a chlorine atom; a (C1-C4) alkyl group; a (C1-C4) alkoxy group; a hydroxy group; C4) an (C1-C4) alkoxy group substituted with at least one group selected from the group consisting of an alkoxy group, a sulfo group and a carboxy group;
R ¹¹ to R ¹³ are each independently hydrogen atom; carboxy group; sulfo group; hydroxy group; acetylamino group; chlorine atom; cyano group; nitro group; sulfamoyl group; (C1-C4) alkyl group; -C4) alkoxy group; (C1-C4) alkoxy group substituted by at least one group selected from the group consisting of hydroxy group, (C1-C4) alkoxy group, sulfo group and carboxy group; (C1-C4) An alkylsulfonyl group; a (C1 to C4) alkylsulfonyl group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group. ] An azo compound represented by the following formula (2), a tautomer thereof, or a salt thereof.

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