JP2015021033A - Azo compound, ink composition, recording method and colored body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dye which is especially excellent in light resistance when recorded on a paper only for inkjet printing purposes and excellent in bronze resistance, moisture resistance, (ozone) gas resistance and storage stability and has high print density, low chroma saturation, low color rendering properties and high-quality black hue, and to provide an ink composition containing the dye.SOLUTION: There is provided an azo compound represented by the formula (1) or a tautomer thereof, or a salt thereof. [wherein, Rrepresents a methyl group or the like; Rrepresents a cyano group or the like; Rand Rrepresent a sulfo group or the like; Rrepresents a sulfo group; R, R, Rand Rrepresent a (C1-C4)alkylcarbonylamino group or the like; R, Rand Rrepresent a sulfo-(C1-C4) alkylthio group or the like; Rto Rrepresent a hydrogen atom, a sulfo group, a carboxyl 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.

  Moisture resistance refers to resistance to a phenomenon in which a dye that forms an image after recording is discolored due to excessive moisture mainly in the surrounding environment contained in the atmosphere or oozes out of the image. In recent years, ink-jet recordings to be exhibited in various environments are regarded as important issues, but those that sufficiently satisfy market demands have not yet been developed.

  Light resistance refers to resistance to light such as sunlight and room light of a recorded image. Currently, printed materials using pigments have excellent light resistance, but printed materials using dyes have not yet been developed that sufficiently satisfy market demands.

  The bronze phenomenon refers to a phenomenon in which the dye becomes flakes on the surface of the recording material due to the association of the dyes or poor ink absorption. When this phenomenon occurs, the gloss, print quality, and print density are all inferior. In particular, when a metal phthalocyanine dye is used as a pigment, it often appears as a `` red floating phenomenon '' in a portion printed at a high density, and the color balance of the entire image becomes uneven and the quality is deteriorated. A pigment that does not cause bronzing is desired. In recent years, glossy paper is often used as a recording medium having a texture close to photographic tone. However, when a bronze phenomenon occurs, glossiness on the surface of the recorded material varies, and the texture of the image is significantly impaired. From this point of view, there is a strong demand for pigments that do not cause bronzing.

  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, bronze 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 processing, it is common to use a compound having absorption at a long wavelength as a method for improving color rendering properties. For example, Non-Patent Document 1 discloses the method.

  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. The polyazo dyes with extended conjugated systems generally have problems such as low water solubility, a bronzing phenomenon in which the 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.

  Recently, gray ink is sometimes used to improve color reproducibility or create a better monochrome image. This gray ink sometimes uses black ink at a low concentration, but there are various problems such as poor fastness such as light resistance, gas resistance and moisture resistance, and poor color rendering. In terms of ozone, no pigment has been developed that meets current market demands.

  Examples of the black compound (black pigment) for inkjet recording include the compounds described in Patent Document 1. Further, examples of the black compound (black pigment) for ink jet recording improved with respect to gas resistance, which has become the most important issue in recent years, include compounds described in Patent Documents 2 to 5. Although the gas resistance of these compounds has been improved, they do not fully meet market demands. Patent Document 5 discloses that a tetrakisazo compound and a water-soluble black compound are used for inkjet recording. However, nothing similar to the water-soluble pentakisazo compound having a benzimidazolopyridone skeleton of the present invention is disclosed.

Japanese Patent Application Laid-Open No. 07-118585 International Publication No. 2005/054374 International Publication No. 2007/077931 International Publication No. 2009/069279 JP 2008-169374 A Processing Technology Vol. 31, No. 9, 1996, 599-602

  The present invention is particularly excellent in light resistance when recorded on inkjet paper, and also excellent in bronze resistance, moisture resistance, (ozone) gas resistance, storage stability in an aqueous solution, high print density, and coloring. An object of the present invention is to provide a pigment having a high-quality black hue with a low degree of color rendering and a color rendering property, and an ink composition containing the pigment, particularly an 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、
Ｒ^１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、
Ｒ^２は、シアノ基；カルバモイル基；又はカルボキシ基；を表し、
Ｒ^３及びＲ^４は、それぞれ独立に、水素原子；（Ｃ１〜Ｃ４）アルキル基；（Ｃ１〜Ｃ４）アルコキシ基；ハロゲン原子；又はスルホ基；を表し、
Ｒ^５は、スルホ基を表し、
Ｒ^６、Ｒ^８、Ｒ^１０、及びＲ^１２は、それぞれ独立に、水素原子；（Ｃ１〜Ｃ４）アルキル基；（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；又はハロゲン原子；を表し、
Ｒ^７、Ｒ^９、及びＲ^１１は、それぞれ独立に、スルホ基；（Ｃ１〜Ｃ４）アルキルチオ基；ヒドロキシ基、スルホ基、及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；（Ｃ１〜Ｃ４）アルコキシ基；又はヒドロキシ基、スルホ基、及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、
Ｒ^１３乃至Ｒ^１５は、それぞれ独立に、水素原子；スルホ基；カルボキシ基；ニトロ基；（Ｃ１〜Ｃ４）アルキル基；スルホ基、又はカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキル基；（Ｃ１〜Ｃ４）アルコキシ基；スルホ基、又はカルボキシ基で置換された（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキルチオ基；スルホ基、又はカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；ヒドロキシ基；又はハロゲン原子;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、
Ｒ^１乃至Ｒ^１５は、式（１）におけるものと同じ意味を表す。]
３）
Ｒ^１３乃至Ｒ^１５が、少なくとも一つの水溶性置換基を有する、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）
式（１）又は（２）において、Ｒ^１３乃至Ｒ^１５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、
Ｒ^５乃至Ｒ^１２の少なくともひとつがスルホ基、若しくはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；又はスルホ基、若しくはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルコキシ基；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）
式（１）又は（２）において、
Ｒ^１が、メチル基；フェニル基；又はスルホフェニル基；であり、
Ｒ^２が、シアノ基；又はカルバモイル基；であり、
Ｒ^３が、水素原子；メチル基；又はメトキシ基；であり、
Ｒ^４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）
式（１）又は（２）において、
Ｒ^１が、メチル基；フェニル基；又はスルホフェニル基；であり、
Ｒ^２が、シアノ基；又はカルバモイル基；であり、
Ｒ^３が、水素原子；メチル基；又はメトキシ基；であり、
Ｒ^４が、スルホ基；であり、
Ｒ^６が、水素原子；（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキル基；又はハロゲン原子；であり、
Ｒ^７が、スルホ基、又はカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；であり、
Ｒ^８が、（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキル基；又はハロゲン原子；であり、
Ｒ^９が、スルホ基、若しくはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；又はスルホ基、若しくはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルコキシ基；であり、
Ｒ^１０が、（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキル基；又はハロゲン原子；であり、
Ｒ^１１が、スルホ基、若しくはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；又はスルホ基、若しくはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルコキシ基；であり、
Ｒ^１２が、水素原子；（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキル基；又はハロゲン原子；であり、
Ｒ^１３乃至Ｒ^１５が、それぞれ独立に、水素原子；スルホ基；カルボキシ基；ニトロ基；（Ｃ１〜Ｃ４）アルコキシ基；スルホ基、若しくはカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；ヒドロキシ基；又はハロゲン原子；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、
７）
式（１）又は（２）において、
Ｒ^１が、メチル基；であり、
Ｒ^２が、シアノ基；又はカルバモイル基；であり、
Ｒ^３が、水素原子；メチル基；又はメトキシ基；であり、
Ｒ^４が、スルホ基；であり、
Ｒ^６が、水素原子；（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキル基；又はハロゲン原子；であり、
Ｒ^７が、スルホ基；スルホ基、又はカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；であり、
Ｒ^８が、（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキル基；又はハロゲン原子；であり、
Ｒ^９が、スルホ基；スルホ基、又はカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；であり、
Ｒ^１０が、（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキル基；又はハロゲン原子；であり、
Ｒ^１１が、スルホ基；スルホ基、又はカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；であり、
Ｒ^１２が、（Ｃ１〜Ｃ４）アルキルカルボニルアミノ基；（Ｃ１〜Ｃ４）アルコキシ基；（Ｃ１〜Ｃ４）アルキル基；又はハロゲン原子；であり、
Ｒ^１３乃至Ｒ^１５が、それぞれ独立に、水素原子；スルホ基；カルボキシ基；メトキシ基；スルホ基、又はカルボキシ基で置換された（Ｃ１〜Ｃ４）アルキルチオ基；又はハロゲン原子；スルホ（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、
８）
式（１）又は（２）において、
Ｒ^１が、メチル基；であり、
Ｒ^２が、シアノ基；又はカルバモイル基；であり、
Ｒ^３が、水素原子；メチル基；又はメトキシ基；であり、
Ｒ^４が、スルホ基；であり、
Ｒ^６が、アセチルアミノ基；メトキシ基；又はハロゲン原子；、
Ｒ^７が、スルホ（Ｃ１〜Ｃ４）アルキルチオ基；又はスルホ（Ｃ１〜Ｃ４）アルコキシ基；、
Ｒ^８が、アセチルアミノ基；メトキシ基；又はハロゲン原子；、
Ｒ^９が、スルホ（Ｃ１〜Ｃ４）アルキルチオ基；又はスルホ（Ｃ１〜Ｃ４）アルコキシ基;、
Ｒ^１０が、アセチルアミノ基；メトキシ基；又はハロゲン原子；、
Ｒ^１１が、スルホプロポキシ基；又はスルホブトキシ基；、
Ｒ^１２が、アセチルアミノ基；メトキシ基；メチル基；又はハロゲン原子；、
Ｒ^１３乃至Ｒ^１５が、それぞれ独立に、水素原子；スルホ基；カルボキシ基；メトキシ基；又は塩素原子；、
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、
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）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、
ｂ）上記９）又は１０）に記載の水性インク組成物、又は、
ｃ）上記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 (C1-C4) alkoxy group; a halogen atom; or a sulfo group;
R ⁵ represents a sulfo group,
R ⁶ , R ⁸ , R ¹⁰ and R ¹² are each independently a hydrogen atom; (C1-C4) alkyl group; (C1-C4) alkoxy group; (C1-C4) alkylcarbonylamino group; or halogen atom ;
R ⁷ , R ⁹ , and R ¹¹ are each independently substituted with at least one group selected from the group consisting of a sulfo group; a (C1-C4) alkylthio group; a hydroxy group, a sulfo group, and a carboxy group. (C1-C4) alkylthio group; (C1-C4) alkoxy group; or (C1-C4) alkoxy group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group ;
R ^{13 to} R ¹⁵ are each independently a hydrogen atom; a sulfo group; a carboxy group; a nitro group; a (C1-C4) alkyl group; a (C1-C4) alkyl group substituted with a sulfo group or a carboxy group; (C1-C4) alkoxy group; (C1-C4) alkoxy group substituted with sulfo group or carboxy group; (C1-C4) alkylthio group; (C1-C4) alkylthio group substituted with sulfo group or carboxy group A hydroxy group; or a halogen atom; ]
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 ¹⁵ represent the same meaning as in formula (1). ]
3)
R ^{13 to} R ^{15 each} have at least one water-soluble substituent, the azo compound according to 1) or 2) or a tautomer thereof, or a salt thereof,
4)
In the formula (1) or (2), at least one of R ^{13 to} R ¹⁵ is a sulfo group; or a carboxy group;
The above 1 wherein at least one of R ^{5 to} R ¹² is a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group; or a (C1-C4) alkoxy group substituted with a sulfo group or a carboxy group; ) To 3), the azo compound or a tautomer thereof, or a salt thereof,
5)
In formula (1) or (2),
R ¹ is a methyl group; a phenyl group; or a sulfophenyl group;
R ² is a cyano group; or a carbamoyl group;
R ³ is a hydrogen atom; a methyl group; or a methoxy group;
The azo compound according to any one of 1) to 4), or a tautomer thereof, or a salt thereof, wherein R ⁴ is a sulfo group;
6)
In formula (1) or (2),
R ¹ is a methyl group; a phenyl group; or a sulfophenyl 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 ⁶ is a hydrogen atom; (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ⁷ is a sulfo group or a (C1-C4) alkylthio group substituted with a carboxy group;
R ⁸ is a (C1-C4) alkylcarbonylamino group; a (C1-C4) alkoxy group; a (C1-C4) alkyl group; or a halogen atom;
R ⁹ is a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group; or a (C1-C4) alkoxy group substituted with a sulfo group or a carboxy group;
R ¹⁰ is (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ¹¹ is a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group; or a (C1-C4) alkoxy group substituted with a sulfo group or a carboxy group;
R ¹² is a hydrogen atom; (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ^{13 to} R ¹⁵ are each independently a hydrogen atom; a sulfo group; a carboxy group; a nitro group; a (C1-C4) alkoxy group; a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group; The azo compound or a tautomer thereof according to any one of 1) to 3), or a salt thereof, which is a group; or a halogen atom;
7)
In 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 ⁶ is a hydrogen atom; (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ⁷ is a sulfo group; a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group;
R ⁸ is a (C1-C4) alkylcarbonylamino group; a (C1-C4) alkoxy group; a (C1-C4) alkyl group; or a halogen atom;
R ⁹ is a sulfo group; a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group;
R ¹⁰ is (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ¹¹ is a sulfo group; a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group;
R ¹² is a (C1-C4) alkylcarbonylamino group; a (C1-C4) alkoxy group; a (C1-C4) alkyl group; or a halogen atom;
R ^{13 to} R ¹⁵ each independently represent a hydrogen atom; a sulfo group; a carboxy group; a methoxy group; a sulfo group or a (C1-C4) alkylthio group substituted with a carboxy group; or a halogen atom; sulfo (C1-C4) ) An alkylthio group;
The azo compound according to any one of 1) to 3) or a tautomer thereof, or a salt thereof,
8)
In 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 ⁶ is an acetylamino group; a methoxy group; or a halogen atom;
R ⁷ is a sulfo (C1-C4) alkylthio group; or a sulfo (C1-C4) alkoxy group;
R ⁸ is an acetylamino group; a methoxy group; or a halogen atom;
R ⁹ is a sulfo (C1-C4) alkylthio group; or a sulfo (C1-C4) alkoxy group;
R ¹⁰ is an acetylamino group; a methoxy group; or a halogen atom;
R ¹¹ is a sulfopropoxy group; or a sulfobutoxy group;
R ¹² is an acetylamino group; a methoxy group; a methyl group; or a halogen atom;
R ^{13 to} R ¹⁵ are each independently a hydrogen atom; a sulfo group; a carboxy group; a methoxy group; or a chlorine atom;
The azo compound or the tautomer thereof according to any one of 1) to 3), or a salt thereof,
9)
An 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 ink composition as described in 9) above, further comprising 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 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 colored body colored by any one of the three methods described in 11) above.

  The azo compound of the present invention or a salt thereof, and an ink composition containing the azo compound are preferably used as an ink for ink jet recording, and are particularly excellent in light resistance when printed on an ink jet dedicated paper and have a very high printing density. The ink composition containing the azo compound of the present invention is an ink jet ink because it has a high, low chroma, high-quality black hue, and excellent moisture resistance, (ozone) gas resistance, and bronze resistance. It is extremely useful as a black ink for recording.

Hereinafter, the present invention will be described in detail.
For the sake of convenience, in the present specification, the “azo compound of the present invention”, including all of the “azo compound of the present invention or a tautomer thereof, or a salt thereof”, will be simply described below. Here, as a tautomer, for example, a structure as shown in the following formula (3) can be mentioned.

In the above 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. .

Examples of the (C1 to C4) alkyl group in R ¹ include a linear or branched unsubstituted group, and a linear group is 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 more preferable.

Examples of the (C1-C4) alkyl group substituted with a carboxy group in R ¹ include those in which a carboxy group is substituted on the carbon atom of the (C1-C4) alkyl 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 substitution number is 1 or 2, preferably 1. Examples of the (C1 to C4) alkyl group as a substituent include the above (C1 to C4) alkyl groups and specific examples, preferred ones, and particularly preferred ones. Specific examples of the (C1 to C4) alkyl group substituted with a carboxy group include a carboxymethyl group, a carboxyethyl group, a carboxy-n-propyl group, a carboxy-n-butyl group, and the like. An ethyl group is preferable, and a carboxymethyl group is more preferable.

Examples of the phenyl group substituted with a sulfo group in R ¹ include those in which a sulfo group is substituted on the carbon atom of the phenyl group. The substitution position of the sulfo group is not particularly limited, and the number of substitution is 1 to 3, preferably 1 or 2, and more preferably 1. Specific examples of the sulfophenyl group include 2-sulfophenyl group, 3-sulfophenyl group, 4-sulfophenyl group, 2,4-disulfophenyl group, 2,5-disulfophenyl group, 3,5-disulfide group, Examples include sulfophenyl group, 2,4,6-trisulfophenyl group, 2-sulfophenyl group, 3-sulfophenyl group, 4-sulfophenyl group, 2,4-disulfophenyl group, 2,5- A disulfophenyl group and a 3,5-disulfophenyl group are preferable, and a 3-sulfophenyl group is more preferable.

In the above formula (1), R ² represents a cyano group; a carbamoyl group; or a carboxy group.

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

Examples of the (C1 to C4) alkyl group in R ^{3 to} R ⁴ include the same as the (C1 to C4) alkyl group in the above R ¹ , specific examples, preferable ones, and particularly preferable ones.

In the above formula (1), examples of the (C1 to C4) alkoxy group in R ³ and R ⁴ include those in which the alkyl part is linear or branched, and linear 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; Straight chain is preferable, and a methoxy group is more preferable.

In the above formula (1), examples of the halogen atom in R ³ and R ⁴ include a fluorine atom; a chlorine atom; a bromine atom; or an iodine atom. A fluorine atom and a chlorine atom are preferable, and a chlorine atom is particularly preferable.

In the above formula (1), R ⁵ represents a sulfo group.

In the formula (1), R ⁶ , R ⁸ , R ¹⁰ and R ¹² are each independently a hydrogen atom; (C1-C4) alkyl group; (C1-C4) alkoxy group; (C1-C4) alkyl. A carbonylamino group; or a halogen atom;

In the above formula (1), as the (C1-C4) alkyl group in R ⁶ , R ⁸ , R ¹⁰ , and R ¹² , the (C1-C4) alkyl group in R ¹ and specific examples, preferred ones, and more. The same thing is mentioned including a preferable thing.

In the above formula (1), the (C1-C4) alkoxy group in R ⁶ , R ⁸ , R ¹⁰ , and R ¹² is preferably a specific example, (C1-C4) alkoxy group in R ³ and R ⁴ above. And the like, including the more preferable ones.

In the above formula (1), examples of the (C1 to C4) alkylcarbonylamino group in R ⁶ , R ⁸ , R ¹⁰ , and R ¹² include those in which the alkyl part is linear or branched. A straight chain 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 A branched chain group such as a group, an isobutylcarbonylamino group, a sec-butylcarbonylamino group, a pivaloylamino group (tert-butylcarbonylamino group), etc., and a straight chain group is preferable, and an acetylamino group is more preferable.

In the above formula (1), the halogen atom in R ⁶ , R ⁸ , R ¹⁰ , and R ¹² is the same as the halogen atom in R ³ and R ⁴ and specific examples, preferable ones, and particularly preferable ones. Is mentioned.

In the formula (1), R ⁷ , R ⁹ , and R ¹¹ are each independently at least one selected from the group consisting of (C1-C4) alkylthio groups; hydroxy groups, sulfo groups, and carboxy groups. (C1-C4) alkylthio group substituted by a group; (C1-C4) alkoxy group; or substituted by at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group (C1-C4) C4) an alkoxy group;

In the above formula (1), examples of the (C1 to C4) alkylthio group in R ⁷ , R ⁹ and R ¹¹ include those in which the alkyl portion is linear or branched, and linear Is preferred. Specific examples include straight chain groups such as methylthio group, ethylthio group, n-propylthio group, and n-butylthio group; branched chain groups such as isopropylthio group, isobutylthio group, sec-propylthio group, and tert-butylthio group; A straight chain is preferable, and a methylthio group is more preferable.

(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 in R ⁷ , R ⁹ and R ¹¹ in the above formula (1) Examples thereof include those having these substituents on any carbon atom in the (C1-C4) alkylthio 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 sulfur atom in the alkylthio group is bonded. Specific examples thereof include those substituted with a hydroxy group such as 2-hydroxyethylthio, 2-hydroxy-n-propylthio, 3-hydroxy-n-propylthio; 2-sulfoethylthio, 3-sulfo-n- Substituted with a sulfo group such as propylthio, 4-sulfo-n-butylthio group; substituted with a carboxy group such as 2-carboxyethylthio, 3-carboxy-n-propylthio, 4-carboxy-n-butylthio And those substituted with a sulfo group are preferred, and a 3-sulfopropylthio group is particularly preferred.

In the above formula (1), the (C1-C4) alkoxy group in R ⁷ , R ⁹ , and R ¹¹ is more preferably a (C1-C4) alkoxy group in R ³ and R ⁴ , specific examples, and preferred ones. The same thing is mentioned including a thing.

(C1 to C4) alkoxy group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group and a carboxy group in R ⁷ , R ⁹ and R ¹¹ in the above formula (1). 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 those substituted with a hydroxy group such as 2-hydroxyethoxy group, 2-hydroxypropoxy group, 3-hydroxy-n-propoxy group; 2-sulfoethoxy group, 2-sulfopropoxy group, 3 -Substituted by a sulfo group such as sulfo-n-propoxy group; Substituted by a carboxy group such as 2-carboxyethoxy group, 2-carboxy-n-propoxy group, 3-carboxy-n-propoxy group; Are preferably substituted with a sulfo group, more preferably a 3-sulfopropoxy group.

A preferred combination of R ¹¹ and R ^{12 is} a combination of R ¹¹ as a sulfo (C1-C4) alkoxy group, R ¹² as a (C1-C4) alkyl group, and R ¹¹ as a sulfopropoxy group (particularly a 3-sulfopropoxy group). R ¹² is preferably a methyl group, or R ¹¹ is a sulfobutoxy group (particularly preferably a 4-sulfobutoxy group), and R ¹² is particularly preferably a methyl group.

In the above formula (1), R ^{13 to} R ¹⁵ are each independently a hydrogen atom; a sulfo group; a carboxy group; a nitro group; a (C1-C4) alkyl group; a sulfo group, or a carboxy group (C1 (C1-C4) alkoxy group; (C1-C4) alkoxy group substituted by sulfo group or carboxy group; (C1-C4) alkylthio group; substituted by sulfo group or carboxy group (C1-C4) alkylthio group; a hydroxy group; or a halogen atom.

Examples of the (C1 to C4) alkyl group in R ^{13 to} R ¹⁵ include the (C1 to C4) alkyl group in R ¹ and the same examples including specific examples, preferable ones, and more preferable ones.

Sulfo group in R ¹³ to ^{R 15,} or substituted with a carboxy group (C1 -C4) alkyl groups, those described above (C1 -C4) sulfo group to a carbon atom of an alkyl group, and / or a carboxyl group is substituted Can be mentioned. Although the substitution position of the sulfo group and / or the carboxy group is not particularly limited, it is preferably substituted at the end of the alkyl group, and the substitution number is 1 or 2, preferably 1. Examples of the (C1 to C4) alkyl group as a substituent include the above (C1 to C4) alkyl groups and specific examples, preferred ones, and particularly preferred ones. Specific examples of the (C1-C4) alkyl group substituted with a sulfo group or a carboxy group include a sulfomethyl group, a sulfoethyl group, a sulfo-n-propyl group, a sulfo-n-butyl group, a carboxymethyl group, and a carboxyethyl group. , A carboxy-n-propyl group, a carboxy-n-butyl group, and the like. A sulfomethyl group, a carboxymethyl group, a sulfoethyl group, and a carboxyethyl group are preferable, and a carboxymethyl group is more preferable.

Examples of the (C1 to C4) alkoxy group in R ^{13 to} R ¹⁵ include the same groups as the (C1 to C4) alkyl group in R ³ and R ⁴ , specific examples, preferable ones, and more preferable ones.

Sulfo group in R ¹³ to ^{R 15,} or substituted with a carboxy group (C1 -C4) alkoxy groups, those described above (C1 -C4) sulfo group to the carbon atom of alkoxy group and / or a carboxyl group is substituted Can be mentioned. Although the substitution position of the sulfo group and / or the carboxy group is not particularly limited, it is preferably substituted at the end of the alkyl group, and the substitution number is 1 or 2, preferably 1. Examples of the (C1 to C4) alkoxy group as a substituent include the above (C1 to C4) alkoxy groups and specific examples, preferable ones, and more preferable ones. Specific examples of the (C1-C4) alkoxy group substituted with a sulfo group or a carboxy group include a sulfomethoxy group, a sulfoethoxy group, a sulfo-n-propoxy group, a sulfo-n-butoxy group, a carboxymethoxy group, a carboxy group An ethoxy group, a carboxy-n-propoxy group, a carboxy-n-butoxy group and the like are mentioned, and a sulfo-n-propoxy group, a carboxy-n-propoxy group, a sulfo-n-butoxy group, and a carboxy-n-butoxy group are preferable. A sulfo-n-propoxy group is more preferable.

The (C1-C4) alkylthio group in R ^{13 to} R ¹⁵ is the same as the (C1-C4) alkylthio group in the above R ⁷ , R ⁹ , and R ¹¹ , including specific examples, preferable ones, and more preferable ones. Is mentioned.

Examples of the (C1 to C4) alkylthio group substituted with a sulfo group or a carboxy group in R ^{13 to} R ¹⁵ include those having these substituents on any carbon atom in the (C1 to C4) alkylthio group. It is done. 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 those substituted with a sulfo group such as 2-sulfoethylthio, 3-sulfo-n-propylthio, 4-sulfo-n-butylthio group, etc .; 2-carboxyethylthio, 3-carboxy- and those substituted with a carboxy group such as n-propylthio and 4-carboxy-n-butylthio; and 2-carboxyethylthio group and 3-sulfopropylthio group are preferable.

Examples of the halogen atom in R ^{13 to} R ¹⁵ include the same halogen atoms as those in R ³ and R ⁴ , including specific examples, preferred ones, and particularly preferred ones.

R ^{13 to} R ¹⁵ each independently represent a hydrogen atom; a sulfo group; a carboxy group; a nitro group; a (C1-C4) alkoxy group; a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group; A group; or a halogen atom; preferably a hydrogen atom; a sulfo group; a carboxy group; a (C1-C4) alkoxy group; or a halogen atom.
In addition, a case where at least one of R ^{13 to} R ¹⁵ is a water-soluble substituent is a particularly preferable embodiment, and a case where the water-soluble substituent is a sulfo group is a particularly preferable embodiment. For example, R ¹³ is hydrogen atom; sulfo group; or chlorine atom; R ¹⁴ is hydrogen atom; sulfo group; methoxy group; or chlorine atom; R ¹⁵ is hydrogen atom; sulfo group; carboxy group; ^This is the case when any one of ^{13 to} R ¹⁵ is a sulfo group.

  The compound which combined the preferable thing described about the various substituents in the said Formula (1), its combination, its substitution position, etc. is more preferable, and what combined the more preferable things is 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 ¹² represent the same meaning as in the above formula (1), and preferred groups and combinations of preferred groups are the same as those in the above formula (1), but the above R ^{5 to} R ¹² is more preferably substituted at the position of formula (2).

^{R 13} to ^{R 15} in the formula (2) represents the same meaning as ^{R 13} to ^{R 15} in the formula (1), combinations of the preferred groups and preferred groups are also the same as in the formula (1).
In formula (2), more preferred R ^{13 to} R ¹⁵ can specify the substitution position and the like. That is, in the benzene ring substituted by R ^{13 to} R ^15, when the substitution position of the azo group is 1-position, R ¹³ is 2-position or 3-position, R ¹⁴ is 4-position, and R ¹⁵ is 5-position or 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 ¹⁵ 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 formulas (1) and (2) include the following combinations (i) to (iv). (Ii) is preferable to (i), and (iii) is most preferable.
(I)
R ¹ is a methyl group; a phenyl group; or a sulfophenyl 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 group;
R ⁶ is a hydrogen atom; (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkoxy group; or halogen atom;
R ⁷ is substituted with a sulfo group, or carboxy group (C1 -C4) alkylthio groups; sulfopropoxy group; or sulfobutoxy group;,
R ⁸ is a (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; or (C1-C4) alkyl group; or a halogen atom,
R ⁹ is a sulfo group, or substituted by a carboxy group (C1 -C4) alkylthio group; or a sulfo group, or substituted by a carboxy group (C1 -C4) alkoxy group;,
R ¹⁰ is a (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; or (C1-C4) alkyl group; or a halogen atom,
R ¹¹ is a sulfo group, or substituted by a carboxy group (C1 -C4) alkylthio group; or a sulfo group, or substituted by a carboxy group (C1 -C4) alkoxy group;,
R ¹² is a hydrogen atom; (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ^{13 to} R ¹⁵ are each independently a hydrogen atom; a sulfo group; a carboxy group; a nitro group; a (C1-C4) alkoxy group; a sulfo group or a (C1-C4) alkylthio group substituted with a carboxy group; a hydroxy group Or a halogen atom;
Is a combination.
(Ii)
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 group;
R ⁶ is a hydrogen atom; (C1-C4) an alkylcarbonylamino group; or a halogen atom;
R ⁷ is substituted with a sulfo group, or carboxy group (C1 -C4) alkylthio groups; sulfopropoxy group; or sulfobutoxy group;,
R ⁸ is an acetylamino group; (C1-C4) alkoxy group; or (C1-C4) alkyl group;
R ⁹ is substituted with a sulfo group, or carboxy group (C1 -C4) alkylthio groups; sulfopropoxy group; or sulfobutoxy group;,
R ¹⁰ is an acetylamino group; (C1-C4) alkyl group; (C1-C4) alkoxy group;
R ¹¹ is a sulfopropoxy group; or a sulfobutoxy group;
R ¹² is a (C1-C4) alkyl group; or a halogen atom;
Each of R ^{13 to} R ¹⁵ independently represents a hydrogen atom; a sulfo group; a carboxy group; a (C1-C4) alkoxy group; or a halogen atom;
Is a combination.
(Iii)
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 group;
R ⁶ is a hydrogen atom; (C1-C4) an alkylcarbonylamino group; or a halogen atom;
R ⁷ is a sulfo (C1-C4) alkylthio group;
R ⁸ is a (C1-C4) alkylcarbonylamino group; or (C1-C4) alkoxy group;
R ⁹ is a sulfo (C1-C4) alkylthio group; a sulfopropoxy group; or a sulfobutoxy group;
R ¹⁰ is an acetylamino group; (C1-C4) alkoxy group; or (C1-C4) alkyl group;
R ¹¹ is a sulfopropoxy group; or a sulfobutoxy group;
R ¹² is a (C1-C4) alkyl group; or a halogen atom;
A combination in which R ^{13 to} R ¹⁵ are each independently a hydrogen atom; a sulfo group; a carboxy group; a methoxy group; or a chlorine atom.
(Iv)
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 sulfo group;
R ⁶ is a hydrogen atom; an acetylamino group; a chlorine atom; or a fluorine atom;
R ⁷ is a sulfo (C1-C4) alkylthio group;
R ⁸ is an acetylamino group;
R ⁹ is a sulfo (C1-C4) alkylthio group; a sulfopropoxy group; or a sulfobutoxy group;
R ¹⁰ is an acetylamino group; a (C1-C4) alkyl group;
R ¹¹ is a sulfopropoxy group; or a sulfobutoxy group;
R ¹² is a (C1-C4) alkyl group; a chlorine atom;
R ¹³ is a hydrogen atom; a sulfo group; or a chlorine atom;
R ¹⁴ is a hydrogen atom; a sulfo group; a methoxy group; or a chlorine atom;
R ¹⁵ is a hydrogen atom; a sulfo group; a carboxy group;
Is a combination.

The azo compound of the present invention represented by the 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 (4) to (13), R ^{1 to} R ¹⁵ represent the same meaning as in the above formula (1).

  A compound represented by the following formula (4) is diazotized by a conventional method, and the obtained diazo compound and a compound represented by the following formula (5) are subjected to a coupling reaction by a conventional method, and represented by the following formula (6). To obtain the compound.

  The obtained compound of the above formula (6) is diazotized by a conventional method, and then the obtained diazo compound and a compound represented by the following formula (7) are subjected to a coupling reaction by a conventional method to obtain the following formula (8) To obtain a compound represented by:

  The obtained compound of the above formula (8) is diazotized by a conventional method, and then the obtained diazo compound and a compound represented by the following formula (9) are subjected to a coupling reaction by a conventional method to obtain the following formula (10) To obtain a compound represented by:

  The obtained compound of the above formula (10) is diazotized by a conventional method, and then the obtained diazo compound and a compound represented by the following formula (11) are subjected to a coupling reaction by a conventional method to obtain the following formula (12) To obtain a compound represented by:

  The obtained compound of the above formula (12) is diazotized by a conventional method, and then the obtained diazo compound and a compound represented by the following formula (13) are subjected to a coupling reaction by a conventional method. The azo compound of the present invention represented by 1) can be obtained.

上記式（１）で表される本発明のアゾ化合物の好適な具体例として、特に限定されるものではないが、下記表１乃至７に挙げた構造式で示される化合物等が挙げられる。
各表においてスルホ基及びカルボキシ基等の官能基は、便宜上、遊離酸の形で記載する。なお、Ａｃはアセチル基を表す。

Although it does not specifically limit as a suitable specific example of the azo compound of this invention represented by the said Formula (1), The compound shown by the structural formula given to the following Table 1 thru | or 7 is mentioned.
In each table, functional groups such as sulfo group and carboxy group are described in the form of free acid for convenience. Ac represents an acetyl group.

  The diazotization of the compound represented by the above formula (4) 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 40 ° C, preferably 0 to 30 ° 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 (4) with the compound of formula (5) 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 [deg.] C, preferably 0 to 30 [deg.] C and an acidic to neutral pH value, for example pH 1-7. 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 (4) and the compound of formula (5) are used in approximately stoichiometric amounts.

  The diazotization of the compound represented by the above formula (6) 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 40 ° C, preferably 0 to 30 ° C. It is carried out using an alkali metal nitrite such as sodium nitrate. Coupling of the diazotized product of the compound represented by formula (6) with the compound of formula (7) 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 [deg.] C, preferably 0 to 30 [deg.] C and an acidic to neutral pH value, for example pH 1-7. 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 (6) and the compound of formula (7) are used in a substantially stoichiometric amount.

  The diazotization of the compound represented by the above formula (8) 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 40 ° C, preferably 0 to 30 ° 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 (8) with the compound of formula (9) 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 [deg.] C, preferably 0 to 30 [deg.] C and an acidic to neutral pH value, e.g. 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 (8) and the compound of formula (9) are used in approximately stoichiometric amounts.

  The diazotization of the compound represented by the above formula (10) 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 40 ° C, preferably 0 to 30 ° 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 (10) with the compound of formula (11) 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 [deg.] C, preferably 0 to 30 [deg.] C and an acidic to neutral pH value, for example pH 1-7. 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 (10) and the compound of formula (11) are used in approximately stoichiometric amounts.

  The diazotization of the compound of formula (12) is carried out in a manner known per se, for example of nitrite, for example sodium nitrite, in an inorganic acid medium, for example at a temperature of −5 to 40 ° C., preferably 0 to 30 ° C. It is carried out using alkali metal nitrite. Coupling of the diazotized compound of the compound of formula (12) with the compound of formula (13) 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 40 ° C, preferably 0 to 30 ° C, and a weakly acidic to alkaline pH value, for example pH 4-12. Since the diazotization reaction liquid is acidic and the reaction system is further acidified by the progress of the coupling reaction, the pH value is adjusted to the preferred pH condition of the reaction liquid by adding a base. The same base as described above can be used. The compound of formula (12) and the compound of formula (13) 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, a salt with a quaternary ammonium ion represented by the following formula (14). 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 (14), 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 of Z ^{1 to} Z ⁴ in the formula (14) include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group and the like. 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 Group, 2-hydroxyethoxy butyl group hydroxy (C1 -C4) alkoxy (C1 -C4) alkyl group. Among these hydroxyethoxy (C1 -C4) alkyl group. Particularly preferred are hydrogen atom; methyl group, hydroxymethyl group, hydroxyethyl group, 3-hydroxypropyl group, 2-hydroxypropyl group, 4-hydroxybutyl group, 3-hydroxybutyl group, 2-hydroxybutyl group, etc. Hydroxy (C1-C4) alkyl group, hydroxyethoxymethyl group, 2-hydroxyethoxyethyl group, 3-hydroxyethoxypropyl group, 2-hydroxyethoxypropyl group, 4-hydroxyethoxybutyl group, 3-hydroxyethoxybutyl group, 2 -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 (14) are shown in Table 8 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 above formula (1) is used as a desired salt include halogen salts of alkali metals such as lithium chloride, sodium chloride and potassium chloride; lithium carbonate, sodium carbonate, carbonate Alkali metal carbonates such as potassium; Alkali metal hydroxides such as lithium hydroxide, sodium hydroxide and potassium hydroxide; Halogen salts of ammonium ions such as ammonium chloride and ammonium bromide; Ammonium hydroxide (ammonia water) And the like.
Examples of the organic cation salt include halogen salts of quaternary ammonium ions represented by the above formula (14) 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 carbamoyl groups can be dyed, and can be widely used for dyeing leather, fabrics, papers, 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 above formula (1) of the present invention as a pigment. % Water-based ink composition. The ink composition of the present invention is prepared using water as a medium, and may contain a water-soluble organic solvent and an ink preparation agent as necessary within a range that does not impair the effects of the present invention. The water-soluble organic solvent may have a function as a dye-dissolving agent, a drying inhibitor (wetting agent), a viscosity modifier, a penetration accelerator, a surface tension modifier, an antifoaming agent, etc., and the ink composition of the present invention It is preferable to contain them. Examples of the ink preparation agent include antiseptic / antifungal agents, pH adjusters, chelating reagents, rust preventives, water-soluble ultraviolet absorbers, water-soluble polymer compounds, dye solubilizers, antioxidants, and surfactants. These additives may be mentioned. 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 (for example, Acid Green 1) ), Black (for example, CI Acid Black 2), and other dyes having various hues.

The ink composition of the present invention can be used by blending one or more of these toning dyes as long as the effects obtained by the azo compound of the present invention are not impaired. Even in this case, the total amount of the coloring matter contained in the ink composition may be in the above range. The mixing ratio of the azo compound of the present invention to the toning dye is approximately 20: 1 to 1: 2, preferably 10: 1 to 1: 1, depending on the hue of the toning dye and the like. It is.
When the ink composition of the present invention is used as an ink for ink-jet recording, it is preferable to use an ink 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 1.0 to 0.1 μm, preferably 0.8 to 0.1 μm.

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

The ink jet recording method of the present invention is a method 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 Glossy Pro [Platinum Grade], professional photo paper, super photo paper or matte photo paper; Seiko Epson Corporation trade name, photo paper (gloss), PM matte paper, Krispia; manufactured by Nippon Hewlett-Packard Co., Ltd., trade name: Advanced Photo Paper, Premium Plus Photo Paper, Premium Glossy Film or Photo Paper; etc., 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 above three methods of 11) to 13) [the three of these a) to c)].
Although there is no restriction | limiting in particular about the substance to be colored, The recording material etc. which are used for said inkjet recording method are mentioned preferably.

The azo compound of the present invention is a black pigment. This compound is easy to synthesize and inexpensive, and has a feature of low saturation, and therefore exhibits a more preferable hue as black. Moreover, since it is excellent in water solubility, the filterability by a membrane filter in the process of manufacturing an ink composition is good.
Further, the ink composition of the present invention containing the azo compound is an aqueous black ink composition, and has good storage stability without solid precipitation, physical property change, color change, etc. after long-term storage.
Furthermore, an image recorded with the ink composition of the present invention is particularly excellent in light resistance, has a very high printing density, low saturation and color rendering, and has a high-quality black hue. Excellent fastness such as moisture resistance, ozone gas resistance and bronze 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.
When the required amount of the target compound was not obtained by one synthesis reaction, the same synthesis reaction was repeated until the required amount was obtained.

[Example 1]
(Process 1)
C. I. Acid Yellow 9 (sodium 4-aminoazobenzene-3,4'-disulfonate) 12.2 parts of water are dissolved in 150.0 parts of water, and the pH is adjusted to 4.0 to 5.0 by adding a 25% aqueous sodium hydroxide solution. Got. After adding 5.7 parts of 40% sodium nitrite aqueous solution, 10.9 parts of 35% hydrochloric acid was added and reacted for about 30 minutes. To this, 0.6 part of sulfamic acid was added and stirred for 5 minutes to obtain a diazo reaction liquid.
On the other hand, 15.4 parts of the compound of the following formula (15) obtained by the method described in International Publication No. 2009/136575 are added to 90.0 parts of water, and pH 4.0 to 5 is added by adding a 25% aqueous sodium hydroxide solution. Solution was obtained as 0.0. The diazo reaction liquid obtained above was dropped into this aqueous solution in about 30 minutes. After the dropwise addition, the mixture was reacted for 2 hours while maintaining the pH at 4.0 to 5.0 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 23.1 parts of a wet cake containing a compound represented by the following formula (16).

(Process 2)
The total amount of the wet cake containing the compound represented by the above formula (16) obtained in Example 1 (Step 1) was added to 100.0 parts of water, and then pH 6.0 was added by adding a 25% aqueous sodium hydroxide solution. An aqueous solution was obtained as ˜7.0. After adding 9.4 parts of 35% hydrochloric acid, 6.6 parts of 40% aqueous sodium nitrite solution was added and reacted for about 30 minutes. The sulfamic acid 0.8 part was added here and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, after adding 13.8 parts of a wet cake of the compound represented by the above formula (15) in 80.0 parts of water, an aqueous solution is obtained at pH 4.0 to 5.0 by adding a 25% aqueous sodium hydroxide solution. It was. This aqueous solution was added dropwise to the diazo reaction solution obtained above in about 60 minutes. After the dropping, the reaction was continued for 10 hours while maintaining the pH at 3.5 to 4.5 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 34.6 parts of a wet cake containing a compound represented by the following formula (17).

(Process 3)
The whole wet cake containing the compound represented by the formula (17) obtained in Example 1 (Step 2) was added to 80.0 parts of water and dissolved by stirring. After adding 9.8 parts of 35% hydrochloric acid, 5.6 parts of 40% aqueous sodium nitrite solution was added and stirred for about 30 minutes. 0.7 parts of sulfamic acid was added here, and it stirred for 5 minutes, and obtained the diazo reaction liquid.
On the other hand, 6.5 parts of the compound of the following formula (18) obtained by the method described in JP-A-2004-083492 is added to 60.0 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 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. The pH was adjusted to 8.0 by adding 15% aqueous sodium carbonate solution, and then salted out by adding sodium chloride. The precipitated crystals were collected by filtration to obtain 78.4 parts of a wet cake containing a compound represented by the following formula (19).

(Process 4)
15.2 parts of 2-methyl-6-nitroaniline were dissolved in 300.0 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 (20).

(Process 5)
To 200.0 parts of the solution containing the compound represented by formula (20) obtained in Example 1 (Step 4), 13.0 parts of methyl cyanoacetate was added and refluxed for 30 minutes, and then methanol was concentrated under reduced pressure. Then, 100.0 parts of water and then sodium carbonate were added to adjust the pH to 7.0 to 7.5, and the precipitated solid was separated by filtration and dried to obtain 8.3 parts of a compound represented by the following formula (21). It was.

(Step 6)
In 100.0 parts of ethanol, 8.3 parts of the compound represented by the formula (21) obtained in Example 1 (Step 5), 12.0 parts of 28% sodium methoxide, and 7.2 parts of methyl acetoacetate After refluxing for 30 minutes, ethanol was concentrated under reduced pressure, 100.0 parts of water and then 35% hydrochloric acid were added to adjust the pH to 7.0 to 7.5, and the precipitated solid was separated by filtration and dried to obtain the following. 11.1 parts of a compound represented by the formula (22) were obtained. The resulting compound represented by the following formula (22) was a mixture of compounds in which the methoxy group was substituted with b or c.

(Step 7)
After slowly adding 5.6 parts of the compound represented by the formula (22) obtained in Example 1 (step 6) at 5 to 10 ° C. in 77.0 parts of 8% fuming sulfuric acid, Reacted for 5 hours. The reaction solution was dropped into 150.0 parts of ice water in about 10 minutes, stirred at 65 to 70 ° C. for 30 minutes, and then the precipitated solid was separated by filtration to obtain a compound represented by the following formula (23). 24.4 parts of a wet cake was obtained. In the compound represented by the following formula (23), 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 8)
26.1 parts of a wet cake containing the compound represented by the formula (19) obtained in Example 1 (Step 3) was added to 100.0 parts of water and dissolved by stirring. After adding 4.7 parts of 35% hydrochloric acid, 1.9 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, 3.3 parts of the compound of the formula (23) obtained in the above Example 1 (Step 7) is added to 100.0 parts of water, and pH 7.0-8. An aqueous solution was obtained as zero. The diazo reaction solution was added dropwise to this aqueous solution in about 30 minutes. After the dropwise addition, the mixture was reacted for 4 hours while maintaining the pH at 7.0 to 8.0 by adding a 15% aqueous sodium carbonate solution. Salting out was performed by adding sodium chloride. The precipitated solid was collected by filtration, dissolved in 200.0 parts of water, 400.0 parts of methanol was added, and the precipitated crystals were collected by filtration. Again, dissolved in 80.0 parts of water, 300.0 parts of methanol were added, and the precipitated crystals were collected by filtration and dried to obtain 4.2 parts of black powder of the compound of the following formula (24).
λmax: 604 nm.

[(A) Preparation of ink]
[Example 2]
Using the compound of the present invention obtained in Example 1 as a dye, the components were mixed at the composition ratio shown in Table 9 below, and the mixture was stirred for about 1 hour until the solid content was dissolved. Then, a 0.45 μm membrane was used. A black ink composition for testing was prepared by filtering with a filter (trade name, cellulose acetate filter paper, manufactured by Advantech).

[Comparative Example 1]
A comparative ink was prepared in the same manner as in Example 5 except that the pigment of the following formula (25) was used as the black pigment for comparison. The following various tests conducted using this ink are referred to as Comparative Example 1. In addition, the compound of following formula (25) is the compound (22) described in Example 1 in JP-A-2008-169374, and was obtained by following the methods described in the literature.

[Comparative Example 2]
A comparative ink was prepared in the same manner as in Example 5 except that the pigment of the following formula (26) was used as the black pigment for comparison. The following various tests conducted using this ink are referred to as Comparative Example 2. In addition, the compound of following formula (26) is compound No. described in Table 6 in JP-A-2008-169374. 13 compounds were obtained according to the method described in the literature.

[(B) Inkjet recording]
Using the respective ink compositions obtained in Example 2 and Comparative Examples 1 and 2, inkjet recording was performed on the following printing paper using an inkjet printer (trade name: EPSON PX-105).
Glossy paper 1: Product made by Canon Glossy Pro Platinum Grade PT-101
Glossy paper 2: Product name made by Canon Inc. Glossy Gold GL-101
Glossy Paper 3: Hewlett-Packard Company Product Name Advanced Photo Paper (Glossy)
At the time of printing, as a test piece for hue evaluation, an image pattern is made so that six gradations of reflection densities of 100%, 85%, 70%, 55%, 40%, and 25% are obtained, and dark black A light black gradation recorded matter was obtained, and this was used as a test piece, and the following evaluation test was performed. Since the gray scale mode is used in any printing, yellow, cyan and magenta recording liquids other than the black recording liquid are not used in combination.

○ 残存率：９４％以上
△ 残存率：９２％以上９４％未満
× 残存率：９２％未満
表１０の結果より、いずれの光沢紙においても、実施例２は比較例１、２よりも耐光性において優れることが確認された。従って、実施例１の化合物を用いたインク組成物は、耐光性において比較例１及び２よりも良好であることがわかる。 [(C) Evaluation]
Regarding the recorded image by the aqueous ink composition of the present invention, the density change of the recorded image was measured using a colorimeter manufactured by GRETAG-MACBETH, trade name: SpectroEye. When measuring colors, all were performed under the conditions of D65 as the light source, DIN NB as the density reference, and a viewing angle of 2 °.
[Light resistance evaluation]
Each recorded image obtained using the ink of Example 2 and Comparative Examples 1 and 2 was naturally dried for 24 hours after printing, and light intensity was measured using a product name, Xenon Weather Meter XL75, manufactured by Suga Test Instruments Co., Ltd. Each test piece was left for 168 hours under the conditions of 100 klux, humidity 60% RH, and temperature 24 ° C.
After completion of the test, the colorimetry was performed using the above colorimeter, and the dye residual ratio was determined by (reflected density Dk after test / reflected density Dk before test) × 100 (%) and evaluated according to the following criteria. . As the evaluation obtained, the one with a high residual ratio indicates that there is little fading due to light and is excellent.
The results are shown in Table 10 below.

○ Residual rate: 94% or more △ Residual rate: 92% or more and less than 94% × Residual rate: less than 92% From the results of Table 10, in any glossy paper, Example 2 is more light-resistant than Comparative Examples 1 and 2. It was confirmed that the film was excellent. Therefore, it can be seen that the ink composition using the compound of Example 1 is better than Comparative Examples 1 and 2 in light resistance.

The azo compound of the present invention or a salt thereof, and an ink composition containing the azo compound have a very high printing density, low saturation, a high-quality black hue, and particularly excellent light resistance. It is suitably used for black ink for various recording such as tools, 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 (C1-C4) alkoxy group; a halogen atom; or a sulfo group;
R ⁵ represents a sulfo group,
R ⁶ , R ⁸ , R ¹⁰ and R ¹² are each independently a hydrogen atom; (C1-C4) alkyl group; (C1-C4) alkoxy group; (C1-C4) alkylcarbonylamino group; or halogen atom ;
R ⁷ , R ⁹ , and R ¹¹ are each independently substituted with at least one group selected from the group consisting of a sulfo group; a (C1-C4) alkylthio group; a hydroxy group, a sulfo group, and a carboxy group. (C1-C4) alkylthio group; (C1-C4) alkoxy group; or (C1-C4) alkoxy group substituted with at least one group selected from the group consisting of a hydroxy group, a sulfo group, and a carboxy group ;
R ^{13 to} R ¹⁵ are each independently a hydrogen atom; a sulfo group; a carboxy group; a nitro group; a (C1-C4) alkyl group; a (C1-C4) alkyl group substituted with a sulfo group or a carboxy group; (C1-C4) alkoxy group; (C1-C4) alkoxy group substituted with sulfo group or carboxy group; (C1-C4) alkylthio group; (C1-C4) alkylthio group substituted with sulfo group or carboxy group A hydroxy group; or a halogen atom; ] An azo compound represented by the following formula (2), a tautomer thereof, or a salt thereof.

[In Formula (2),
R ^{1 to} R ¹⁵ represent the same meaning as in formula (1). ] The azo compound or a tautomer thereof according to claim 1 or 2, or a salt thereof, wherein R ^{13 to} R ¹⁵ have at least one water-soluble substituent. In the formula (1) or (2), at least one of R ^{13 to} R ¹⁵ is a sulfo group; or a carboxy group;
At least one of R ^{5 to} R ¹² is a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group; or a (C1-C4) alkoxy 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. In formula (1) or (2),
R ¹ is a methyl group; a phenyl group; or a sulfophenyl group;
R ² is a cyano group; or a carbamoyl group;
R ³ is a hydrogen atom; a methyl group; or a methoxy group;
The azo compound according to any one of claims 1 to 4, or a tautomer thereof, or a salt thereof, wherein R ⁴ is a sulfo group. In formula (1) or (2),
R ¹ is a methyl group; a phenyl group; or a sulfophenyl 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 ⁶ is a hydrogen atom; (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ⁷ is a sulfo group or a (C1-C4) alkylthio group substituted with a carboxy group;
R ⁸ is a (C1-C4) alkylcarbonylamino group; a (C1-C4) alkoxy group; a (C1-C4) alkyl group; or a halogen atom;
R ⁹ is a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group; or a (C1-C4) alkoxy group substituted with a sulfo group or a carboxy group;
R ¹⁰ is (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ¹¹ is a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group; or a (C1-C4) alkoxy group substituted with a sulfo group or a carboxy group;
R ¹² is a hydrogen atom; (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ^{13 to} R ¹⁵ are each independently a hydrogen atom; a sulfo group; a carboxy group; a nitro group; a (C1-C4) alkoxy group; a (C1-C4) alkylthio group substituted with 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, which is a group; or a halogen atom. In 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 ⁶ is a hydrogen atom; (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ⁷ is a sulfo group; a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group;
R ⁸ is a (C1-C4) alkylcarbonylamino group; a (C1-C4) alkoxy group; a (C1-C4) alkyl group; or a halogen atom;
R ⁹ is a sulfo group; a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group;
R ¹⁰ is (C1-C4) alkylcarbonylamino group; (C1-C4) alkoxy group; (C1-C4) alkyl group; or halogen atom;
R ¹¹ is a sulfo group; a (C1-C4) alkylthio group substituted with a sulfo group or a carboxy group;
R ¹² is a (C1-C4) alkylcarbonylamino group; a (C1-C4) alkoxy group; a (C1-C4) alkyl group; or a halogen atom;
R ^{13 to} R ¹⁵ each independently represent a hydrogen atom; a sulfo group; a carboxy group; a methoxy group; a sulfo group or a (C1-C4) alkylthio group substituted with a carboxy group; or a halogen atom; sulfo (C1-C4) ) An alkylthio group;
The azo compound according to any one of claims 1 to 3, or a tautomer thereof, or a salt thereof. In 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 ⁶ is an acetylamino group; a methoxy group; or a halogen atom;
R ⁷ is a sulfo (C1-C4) alkylthio group; or a sulfo (C1-C4) alkoxy group;
R ⁸ is an acetylamino group; a methoxy group; or a halogen atom;
R ⁹ is a sulfo (C1-C4) alkylthio group; or a sulfo (C1-C4) alkoxy group;
R ¹⁰ is an acetylamino group; a methoxy group; or a halogen atom;
R ¹¹ is a sulfopropoxy group; or a sulfobutoxy group;
R ¹² is an acetylamino group; a methoxy group; a methyl group; or a halogen atom;
R ^{13 to} R ¹⁵ are each independently a hydrogen atom; a sulfo group; a carboxy group; a methoxy group; or a chlorine atom;
The azo compound according to any one of claims 1 to 3, or a tautomer thereof, or a salt thereof. An 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 coloring matter. The 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.