JPWO2009119412A1 - Water-soluble azo compound or salt thereof, ink composition and colored body - Google Patents

Abstract

As a yellow pigment having a hue with high sharpness suitable for ink jet recording, high fastness of various recorded materials, and excellent storage stability of the ink composition when the ink composition is prepared, the following formula (1 And a tautomer thereof, or a salt thereof. Also provided are ink compositions containing these compounds. Wherein R1 and R2 are each independently a hydrogen atom; a chlorine atom; a sulfo group; a substituted or unsubstituted C1-C4 alkoxy group; a substituted or unsubstituted alkylcarbonylamino group; a substituted or unsubstituted alkylsulfonyl group; A substituted alkylthio group, R3 represents a methyl group, etc., and R4 represents a sulfo group, etc.)

Description

  The present invention relates to a water-soluble azo compound or a salt thereof, an ink composition containing the same, an ink jet recording method using the ink composition, and a colored body colored with the compound or the like.

Among various color recording methods, one of the representative recording methods using an ink jet printer has developed various ink ejection methods, all of which generate ink droplets, Recording is performed by attaching to a recording material (paper, film, fabric, etc.). Since this method has features that the recording head and the recording material are not in direct contact with each other and no noise is generated and is quiet, and it is easy to downsize, increase the speed and color, it has been rapidly spread in recent years. The growth is expected to continue.
Conventionally, as inks such as fountain pens and felt pens and inks for ink jet recording, inks in which a water-soluble dye is dissolved in an aqueous medium have been used. In these inks, a water-soluble organic solvent is generally added to prevent clogging of the ink at the pen tip or the ink discharge nozzle. These inks give a recorded image of sufficient density, do not cause clogging of the pen tip and nozzles, have good drying properties on the recording material, have little bleeding, and have excellent storage stability. Is required. The formed recorded image is required to have fastness such as water resistance, moisture resistance, light resistance and ozone gas resistance.
Ink jet printer nozzle clogging occurs when the water content in the ink evaporates in the vicinity of the nozzle before other solvents and additives, and the pigment solidifies and precipitates when the composition state is low in water and high in solvents and additives. There are many things that come from doing. Therefore, one of the very important required performances is that the dye is not easily precipitated as a solid even when the ink is evaporated and dried. For this reason, high solubility in solvents and additives is one of the properties required for pigments.

  By the way, in order to record image or character information on a color display of a computer in color by an ink jet printer, generally a subtraction method using four colors of ink of yellow (Y), magenta (M), cyan (C), and black (K). Mixed colors are used, whereby the recorded image is expressed in color. In order to reproduce an additive color mixture image of red (R), green (G), and blue (B) in a CRT (CRT) display etc. as faithfully as possible with a subtractive color mixture image, each dye used in the ink, especially Y, M , C are desired to have a hue close to standard and clear. Further, the ink is required to be stable against long-term storage, have a high recorded image density as described above, and be excellent in fastness such as water resistance, moisture resistance, light resistance, and ozone gas resistance. . Here, the ozone gas resistance means that an ozone gas having an oxidizing action existing in the air reacts with a dye (dye) of a recorded image on the recording material or in the recording material, and discolors the printed image. It is the resistance to the phenomenon of making it happen. Ozone gas is regarded as a main causative substance that promotes the fading phenomenon of the ink jet recorded image. Since this color fading phenomenon is characteristic of inkjet images, improvement of ozone gas resistance is an important technical problem in this field.

Examples of yellow pigments for inkjet having excellent water solubility and sharpness include C.I. I. (Color Index) Acid Yellow 17 and C.I. I. Acid Yellow 23 is mentioned, and all of these are disclosed in Patent Documents 1 to 3.
Patent Document 4 discloses a magenta image dye in which a hydroxy group is essential as the group G, and a color photographic recording material containing the same.
Patent Document 5 discloses a pyrazolopyrimidin-7-one azo dye and a thermal transfer dye donating material containing the dye.

Japanese Unexamined Patent Application Publication No. 2003-171484, Example 3 JP 2002-241648 A, Example 1 JP 2003-165932 A, Examples 3 and 6 JP 58-123537 A JP-A-7-137466

C. I. Acid Yellow 17 and C.I. I. Acid Yellow 23 does not have sufficient performance in all of various fastnesses such as hue, vividness, and light resistance, and storage stability. Accordingly, there has been a demand for the development of a yellow pigment that is further improved in terms of fastness, color density, hue, sharpness, and the like.
The present invention is a water-soluble yellow dye (compound) having a high solubility in water, a hue and sharpness suitable for ink jet recording, a high color density, and particularly excellent fastness such as ozone gas resistance and light resistance. An object of the present invention is to provide an ink composition containing the same and having good storage stability.

  As a result of intensive studies, the inventors of the present invention contain a specific water-soluble azo compound represented by the following formula (1) or a tautomer thereof, or a salt thereof, and a dye as a result thereof. The present inventors have found that an ink composition to solve the above-described problems has completed the present invention.

［式（１）中、
Ｒ^１及びＲ^２はそれぞれ独立に水素原子；フッ素原子；塩素原子；スルホ基；カルボキシ基；スルファモイル基；カルバモイル基；無置換Ｃ１−Ｃ４アルキル基；ヒドロキシ基、無置換Ｃ１−Ｃ４アルコキシ基、ヒドロキシ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アルコキシ基、若しくは無置換Ｃ１−Ｃ４アルコキシ基；ヒドロキシ基、スルホ基、若しくはカルボキシ基で置換されたモノ若しくはジＣ１−Ｃ４アルキルアミノ基、若しくは無置換モノ若しくはジＣ１−Ｃ４アルキルアミノ基；ヒドロキシ基若しくはカルボキシ基で置換されたＣ１−Ｃ４アルキルカルボニルアミノ基、若しくは無置換Ｃ１−Ｃ４アルキルカルボニルアミノ基；ヒドロキシ基、スルホ基、若しくはカルボキシ基で置換されたＮ’−Ｃ１−Ｃ４アルキルウレイド基、若しくは無置換Ｎ’−Ｃ１−Ｃ４アルキルウレイド基；ベンゼン環が塩素原子、無置換Ｃ１−Ｃ４アルキル基、ニトロ基、スルホ基、若しくはカルボキシ基で置換されたフェニルアミノ基、若しくは無置換フェニルアミノ基；ベンゼン環が塩素原子、無置換Ｃ１−Ｃ４アルキル基、ニトロ基、スルホ基、若しくはカルボキシ基で置換されたベンゾイルアミノ基、若しくは無置換ベンゾイルアミノ基；ベンゼン環が塩素原子、無置換Ｃ１−Ｃ４アルキル基、ニトロ基、スルホ基、若しくはカルボキシ基で置換されたフェニルスルホニルアミノ基、若しくは無置換フェニルスルホニルアミノ基；スルホ基若しくはカルボキシ基で置換されたＣ１−Ｃ４アルキルスルホニル基、若しくは無置換Ｃ１−Ｃ４アルキルスルホニル基；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、若しくは無置換Ｃ１−Ｃ４アルキルチオ基；又は、スルホ基で置換されたベンゾイル基、若しくは無置換ベンゾイル基；を表し、
Ｒ^３は水素原子、メチル基、又はカルボキシ基を表し、
Ｒ^４は、スルホ基又はカルボキシ基を表す。］
２）
Ｒ^１及びＲ^２が、それぞれ独立に水素原子；フッ素原子；塩素原子；スルホ基；カルボキシ基；無置換Ｃ１−Ｃ４アルコキシ基；無置換Ｃ１−Ｃ４アルキルカルボニルアミノ基；スルホ基若しくはカルボキシ基で置換されたＣ１−Ｃ４アルキルスルホニル基、若しくは無置換Ｃ１−Ｃ４アルキルスルホニル基；又は、スルホ基若しくはカルボキシ基で置換されたＣ１−Ｃ４アルキルチオ基、若しくは無置換Ｃ１−Ｃ４アルキルチオ基；であり、
Ｒ^３がメチル基、又はカルボキシ基である、上記１）に記載の水溶性アゾ化合物若しくはその互変異性体、又はそれらの塩、
３）
Ｒ^１及びＲ^２が、それぞれ独立に水素原子；塩素原子；スルホ基；カルボキシ基；無置換Ｃ１−Ｃ４アルコキシ基；無置換Ｃ１−Ｃ４アルキルカルボニルアミノ基；無置換Ｃ１−Ｃ４アルキルスルホニル基；又は無置換Ｃ１−Ｃ４アルキルチオ基；であり、
Ｒ^３がメチル基、又はカルボキシ基である、上記１）に記載の水溶性アゾ化合物若しくはその互変異性体、又はそれらの塩、
４）
Ｒ^３がメチル基である上記１）乃至３）のいずれか一項に記載の水溶性アゾ化合物若しくはその互変異性体、又はそれらの塩、
５）
Ｒ^１がスルホ基であり、Ｒ^２が水素原子である上記１）乃至４）のいずれか一項に記載の水溶性アゾ化合物若しくはその互変異性体、又はそれらの塩、
６）
上記１）乃至５）のいずれか一項に記載の水溶性アゾ化合物若しくはその互変異性体、又はそれらの塩を、色素として含有するインク組成物、
７）
水溶性有機溶剤をさらに含有する上記６）に記載のインク組成物、
８）
インクジェット記録用である上記６）又は７）に記載のインク組成物、
９）
上記６）乃至８）のいずれか一項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付着させることにより記録を行うインクジェット記録方法。
１０）
上記被記録材が情報伝達用シートである上記９）に記載のインクジェット記録方法、
１１）
上記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ートである上記１０）に記載のインクジェット記録方法、
１２）
上記１）乃至５）のいずれか一項に記載の水溶性アゾ化合物若しくはその互変異性体、若しくはそれらの塩、又は上記６）乃至８）のいずれか一項に記載のインク組成物で着色された着色体、
１３）
着色がインクジェットプリンタによりなされた上記１２）に記載の着色体、
１４）
上記６）乃至８）のいずれか一項に記載のインク組成物を含む容器が装填されたインクジェットプリンタ、
に関する。That is, the present invention
1)
A water-soluble azo compound represented by the following formula (1) or a tautomer thereof, or a salt thereof;

[In Formula (1),
R ¹ and R ² are each independently hydrogen atom; fluorine atom; chlorine atom; sulfo group; carboxy group; sulfamoyl group; carbamoyl group; unsubstituted C1-C4 alkyl group; hydroxy group, unsubstituted C1-C4 alkoxy group, hydroxy C1-C4 alkoxy group substituted with a C1-C4 alkoxy group, a sulfo group, or a carboxy group, or an unsubstituted C1-C4 alkoxy group; mono- or di-C1-C4 substituted with a hydroxy group, a sulfo group, or a carboxy group An alkylamino group, or an unsubstituted mono- or di-C1-C4 alkylamino group; a C1-C4 alkylcarbonylamino group substituted with a hydroxy group or a carboxy group, or an unsubstituted C1-C4 alkylcarbonylamino group; a hydroxy group, a sulfo group Or a carboxy group N′-C1-C4 alkylureido group, or unsubstituted N′-C1-C4 alkylureido group; the benzene ring is substituted with a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or a carboxy group A substituted phenylamino group or an unsubstituted phenylamino group; a benzoylamino group or an unsubstituted benzoylamino group in which the benzene ring is substituted with a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or a carboxy group A phenylbenzeneamino group substituted with a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or a carboxy group, or an unsubstituted phenylsulfonylamino group; substituted with a sulfo group or a carboxy group C1-C4 alkylsulfonyl group or unsubstituted C1-C4 Alkylsulfonyl group; a sulfo group or a C1-C4 alkylthio group substituted by a carboxy group, or unsubstituted C1-C4 alkylthio group; or a benzoyl group substituted with a sulfo group, or unsubstituted benzoyl group; represent,
R ³ represents a hydrogen atom, a methyl group, or a carboxy group,
R ⁴ represents a sulfo group or a carboxy group. ]
2)
R ¹ and R ² are each independently hydrogen atom; fluorine atom; chlorine atom; sulfo group; carboxy group; unsubstituted C1-C4 alkoxy group; unsubstituted C1-C4 alkylcarbonylamino group; substituted with sulfo group or carboxy group A substituted C1-C4 alkylsulfonyl group, or an unsubstituted C1-C4 alkylsulfonyl group; or a C1-C4 alkylthio group substituted with a sulfo group or a carboxy group, or an unsubstituted C1-C4 alkylthio group;
R ³ is a methyl group or a carboxy group, the water-soluble azo compound according to 1) or a tautomer thereof, or a salt thereof,
3)
R ¹ and R ² are each independently a hydrogen atom; a chlorine atom; a sulfo group; a carboxy group; an unsubstituted C1-C4 alkoxy group; an unsubstituted C1-C4 alkylcarbonylamino group; an unsubstituted C1-C4 alkylsulfonyl group; or An unsubstituted C1-C4 alkylthio group;
R ³ is a methyl group or a carboxy group, the water-soluble azo compound according to 1) or a tautomer thereof, or a salt thereof,
4)
The water-soluble azo compound or a tautomer thereof according to any one of the above 1) to 3), wherein R ³ is a methyl group, or a salt thereof,
5)
The water-soluble azo compound or a tautomer thereof according to any one of the above 1) to 4), wherein R ¹ is a sulfo group, and R ² is a hydrogen atom, or a salt thereof,
6)
An ink composition comprising the water-soluble azo compound according to any one of 1) to 5) or a tautomer thereof, or a salt thereof as a coloring matter;
7)
The ink composition as described in 6) above, further comprising a water-soluble organic solvent,
8)
The ink composition according to 6) or 7), which is for inkjet recording;
9)
An ink jet recording method in which recording is performed by using the ink composition according to any one of 6) to 8) as an ink, and ejecting ink droplets of the ink in accordance with a recording signal to adhere to a recording material. .
10)
The inkjet recording method according to 9), wherein the recording material is an information transmission sheet;
11)
The inkjet recording method according to 10), wherein the information transmission sheet is a sheet having an ink receiving layer containing a porous white inorganic substance,
12)
Colored with the water-soluble azo compound according to any one of 1) to 5) or a tautomer thereof, or a salt thereof, or the ink composition according to any one of 6) to 8) above. Colored body,
13)
The colored body as described in 12) above, wherein coloring is performed by an inkjet printer,
14)
An inkjet printer loaded with a container containing the ink composition according to any one of 6) to 8) above;
About.

  The water-soluble azo compound represented by the above formula (1) of the present invention or a tautomer thereof, or a salt thereof is extremely excellent in solubility in water, and, for example, in the process of producing an ink composition, for example, a membrane. It is characterized by good filterability for the filter, and gives a yellow hue that is very clear on an ink jet recording paper and has high brightness and color density. Further, the ink composition of the present invention containing this compound has very good storage stability without solid precipitation, change in physical properties, change in hue, etc. after long-term storage. A printed matter using the ink composition of the present invention as an ink for ink jet recording has an ideal hue as a yellow hue without selecting a recording material (for example, paper, film, etc.), and a photographic color image Can be reproduced faithfully on paper. Furthermore, even when recording on a recording material coated with a porous white inorganic material such as paper for exclusive use for photographic image quality and film, it is excellent in various fastnesses such as gas resistance and light resistance, and is recorded in photographic style. Excellent long-term storage stability of images. As described above, the water-soluble azo compound represented by the formula (1) or a tautomer thereof, or a salt thereof is extremely useful as a yellow pigment for ink, particularly for ink jet recording.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in detail. In the present specification, unless otherwise specified, acidic functional groups such as sulfo groups and carboxy groups are represented in the form of free acids. The water-soluble azo compound of the present invention or a tautomer thereof, or a salt thereof is a water-soluble yellow dye.
Further, in the following description, unless otherwise specified, in order to avoid complications, the “water-soluble azo compound of the present invention or a tautomer thereof, or a salt thereof” includes all of “the present invention. For convenience, it is described as “water-soluble azo compound”.

  The water-soluble azo compound of the present invention includes a compound represented by the following formula (1).

  Examples of the compound represented by the above formula (1) include tautomers represented by the following formulas (2) and (3). These tautomers are also included in the present invention.

In the above formula (2), R ^{1 to} R ⁴ have the same meaning as in the formula (1).

In the above formula (3), R ^{1 to} R ⁴ have the same meaning as in formula (1).

In the above formula (1), R ¹ and R ² are each independently a hydrogen atom; a fluorine atom; a chlorine atom; a sulfo group; a carboxy group; a sulfamoyl group; a carbamoyl group; an unsubstituted C1-C4 alkyl group; A substituted C1-C4 alkoxy group, a hydroxy C1-C4 alkoxy group, a sulfo group, or a C1-C4 alkoxy group substituted with a carboxy group, or an unsubstituted C1-C4 alkoxy group; substituted with a hydroxy group, a sulfo group, or a carboxy group Mono- or di-C1-C4 alkylamino group, or unsubstituted mono- or di-C1-C4 alkylamino group; C1-C4 alkylcarbonylamino group substituted with a hydroxy group or a carboxy group, or unsubstituted C1-C4 alkylcarbonyl Amino group; hydroxy group, sulfo group, young N'-C1-C4 alkylureido group substituted with a carboxy group, or unsubstituted N'-C1-C4 alkylureido group; the benzene ring is a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or A phenylamino group substituted with a carboxy group, or an unsubstituted phenylamino group; a benzoylamino group in which the benzene ring is substituted with a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or a carboxy group; A substituted benzoylamino group; a phenylsulfonylamino group in which the benzene ring is substituted with a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or a carboxy group; or an unsubstituted phenylsulfonylamino group; a sulfo group or a carboxy group A C1-C4 alkylsulfonyl group substituted with An unsubstituted C1-C4 alkylsulfonyl group; a C1-C4 alkylthio group substituted with a sulfo group or a carboxy group, or an unsubstituted C1-C4 alkylthio group; or a benzoyl group substituted with a sulfo group, or an unsubstituted benzoyl group To express.

Among the above, preferred as R ¹ and R ² are a hydrogen atom; a fluorine atom; a chlorine atom; a sulfo group; a carboxy group; an unsubstituted C1-C4 alkyl group; a hydroxy group, an unsubstituted C1-C4 alkoxy group, and a hydroxy C1. A C1-C4 alkoxy group substituted with a C4 alkoxy group, a sulfo group, or a carboxy group, or an unsubstituted C1-C4 alkoxy group; a mono- or di-C1-C4 alkyl substituted with a hydroxy group, a sulfo group, or a carboxy group An amino group, or an unsubstituted mono- or di-C1-C4 alkylamino group; a C1-C4 alkylcarbonylamino group substituted with a hydroxy group or a carboxy group, or an unsubstituted C1-C4 alkylcarbonylamino group; a sulfo group or a carboxy group; Substituted C1-C4 alkyl sulfo Group, or unsubstituted C1-C4 alkylsulfonyl group; or, C1-C4 alkylthio group substituted by a sulfo group or carboxy group, or unsubstituted C1-C4 alkylthio group; a. More preferably, a hydrogen atom; a fluorine atom; a chlorine atom; a sulfo group; a carboxy group; an unsubstituted C1-C4 alkoxy group; an unsubstituted C1-C4 alkylcarbonylamino group; a C1-C4 alkyl substituted with a sulfo group or a carboxy group A sulfonyl group or an unsubstituted C1-C4 alkylsulfonyl group; or a C1-C4 alkylthio group substituted with a sulfo group or a carboxy group, or an unsubstituted C1-C4 alkylthio group. More preferably, a hydrogen atom; a chlorine atom; a sulfo group; a carboxy group; an unsubstituted C1-C4 alkoxy group; an unsubstituted C1-C4 alkylcarbonylamino group; an unsubstituted C1-C4 alkylsulfonyl group; or an unsubstituted C1-C4 alkylthio Group;
As a combination of R ¹ and R ² , one in which one is a hydrogen atom and the other is the above group; or one in which one is a chlorine atom and the other is a chlorine atom or a carboxy group is preferable.

The substitution positions of R ¹ and R ² are not particularly limited. However, when the substitution position of the azo group is 1-position and the substitution position of the sulfo group is 2-position, the 4-position and / or 5-position is preferred.

The unsubstituted C1-C4 alkyl group for R ¹ and R ² may be either linear or branched, but is preferably linear. Specific examples of the C1-C4 alkyl group include straight chain such as methyl, ethyl, n-propyl and n-butyl; branched chain such as isopropyl, isobutyl, sec-butyl and tert-butyl.

As the unsubstituted C1-C4 alkoxy group in R ¹ and R ² , both linear and branched chains are preferable. Specific examples include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy and the like.
When the alkoxy group is substituted with a hydroxy group, an unsubstituted C1-C4 alkoxy group, a hydroxy C1-C4 alkoxy group, a sulfo group, or a carboxy group, specific examples thereof include, for example, 2-hydroxyethoxy, 2-hydroxy Hydroxy C1-C4 alkoxy groups such as propoxy, 3-hydroxypropoxy; methoxyethoxy, ethoxyethoxy, n-propoxyethoxy, isopropoxyethoxy, n-butoxyethoxy, methoxypropoxy, ethoxypropoxy, n-propoxypropoxy, isopropoxybutoxy, unsubstituted C1-C4 alkoxy C1-C4 alkoxy group such as n-propoxybutoxy; hydroxy C1-C4 alkoxy C1-C4 alkoxy group such as 2-hydroxyethoxyethoxy; 3-sulfopropoxy, 4- Sulfo C1-C4 alkoxy group such as Ruhobutokishi; carboxymethoxy, 2-carboxyethoxy, carboxy C1-C4 alkoxy group such as a 3-carboxypropoxy; and the like.

As the alkyl moiety of the unsubstituted mono- or di-C1-C4 alkylamino group in R ¹ and R ² , either linear or branched is preferable. Specific examples thereof include linear chains such as methylamino, ethylamino, n-propylamino, isopropylamino, n-butylamino, dimethylamino, diethylamino, di-n-propylamino, di-n-butylamino; sec- Branched chain such as butylamino, tert-butylamino, diisopropylamino, and the like.
When the mono- or di-C1-C4 alkylamino group is substituted with a hydroxy group, a sulfo group, or a carboxy group, specific examples thereof include, for example, 2-hydroxyethylamino, 2-hydroxypropylamino, 2,2 Hydroxy-substituted mono- or di-C1-C4 alkylamino groups such as'-dihydroxydiethylamino; sulfo-substitutions such as 2-sulfoethylamino, 3-sulfopropylamino, 4-sulfobutylamino, 3,3'-disulfodipropylamino Mono- or di-C1-C4 alkylamino group; carboxy-substituted mono- or di-C1-C4 alkylamino group such as carboxymethylamino, 2-carboxyethylamino, 3-carboxypropylamino, 2,2′-dicarboxydiethylamino, etc. Can be mentioned.

The alkyl moiety of the unsubstituted C1-C4 alkylcarbonylamino group in R ¹ and R ² may be either a straight chain or a branched chain, but is preferably a straight chain. Specific examples include acetylamino, propanoylamino, butanoylamino, pentanoylamino and the like.
When the C1-C4 alkylcarbonylamino group is substituted with a hydroxy group or a carboxy group, specific examples of the C1-C4 alkylcarbonylamino group include, for example, hydroxyethanoylamino, 2-hydroxypropanoylamino, 4 -Hydroxy C1-C4 alkylcarbonylamino group such as hydroxybutanoylamino; Carboxy C1-C4 alkylcarbonylamino group such as 3-carboxypropanoylamino; and the like.

As the N′—C 1 -C 4 alkylureido group in R ¹ and R ^2, those having a substituent are preferred rather than unsubstituted.
When the N′-C1-C4 alkylureido group is substituted with a hydroxy group, a sulfo group, or a carboxy group, specific examples thereof include, for example, N′-2-hydroxyethylureido, N′-3-hydroxy N′-hydroxy C1-C4 alkylureido group such as propylureido; N′-sulfoC1-C4 alkylureido group such as N′-2-sulfoethylureido, N′-3-sulfopropylureido; N′-carboxymethyl And N′-carboxy C1-C4 alkylureido groups such as ureido, N′-2-carboxyethylureido, N′-3-carboxypropylureido, N′-4-carboxybutylureido; and the like.

When the phenylamino group, benzoylamino group, or phenylsulfonylamino group having a substituent in R ¹ and R ² is a substituent of the benzene ring contained in each group is an unsubstituted C1-C4 alkyl group, the alkyl The group may be linear, branched, or cyclic, but is preferably linear or branched. Specific examples include, for example, linear chains such as methyl, ethyl, n-propyl, and n-butyl; branched chains such as isopropyl, isobutyl, sec-butyl, and tert-butyl.

Specific examples of the phenylamino group in which the benzene ring in R ¹ and R ² is substituted with a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or a carboxy group include 2-chlorophenylamino, 4- Chlorine atom-substituted phenylamino groups such as chlorophenylamino and 2,4-dichlorophenylamino; C1-C4 alkyl-substituted phenylamino groups such as 2-methylphenylamino, 4-methylphenylamino and 4-tert-butylphenylamino; Nitro-substituted phenylamino groups such as nitrophenylamino and 4-nitrophenylamino; sulfo-substitutions such as 3-sulfophenylamino, 4-sulfophenylamino, 2,4-disulfophenylamino, and 3,5-disulfophenylamino Phenylamino group; 2-carboxyphenylamino, 4 Carboxyphenyl amino, 2,5-carboxyphenyl amino, 3,5-dicarboxyphenyl carboxy-substituted phenylamino group phenylamino and the like; and the like.

Specific examples of the benzoylamino group in which the benzene ring in R ¹ and R ² is substituted with a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or a carboxy group include, for example, 2-chlorobenzoylamino, 4- Chloro atom substituted benzoylamino groups such as chlorobenzoylamino and 2,4-dichlorophenylamino; C1-C4 alkyl substituted benzoylamino groups such as 2-methylbenzoylamino, 3-methylbenzoylamino and 4-methylbenzoylamino; 2-nitro Nitro-substituted benzoylamino groups such as benzoylamino, 4-nitrobenzoylamino and 3,5-dinitrobenzoylamino; sulfo-substituted benzoylamino groups such as 2-sulfobenzoylamino and 4-sulfobenzoylamino; 2-carboxybenzoylamino, 4 -Carboxy Nzoiruamino, 3,5-carboxymethyl benzoyl carboxy-substituted benzoylamino group of the amino or the like; and the like.

Specific examples of the phenylsulfonylamino group in which the benzene ring in R ¹ and R ² is substituted with a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or a carboxy group include, for example, 2-chlorophenylsulfonylamino, Chlorine atom substituted phenylsulfonylamino groups such as 4-chlorophenylsulfonylamino; C1-C4 alkyl substituted phenylsulfonylamino groups such as 2-methylphenylsulfonylamino, 4-methylphenylsulfonylamino, 4-tert-butylphenylsulfonylamino; 2 Nitro-substituted phenylsulfonylamino groups such as -nitrophenylsulfonylamino, 3-nitrophenylsulfonylamino, 4-nitrophenylsulfonylamino; 3-sulfophenylsulfonylamino, 4-sulfophenylsulfonyl Sulfo-substituted phenylsulfonylamino group amino, etc .; 3-carboxyphenyl sulfonylamino, 4-carboxyphenyl sulfonyl carboxy-substituted phenylsulfonylamino group of the amino or the like; and the like.

As the unsubstituted C1-C4 alkylsulfonyl group in R ¹ and R ² , both a straight chain and a branched chain are preferable, but a straight chain is more preferable. Specific examples thereof include linear ones such as methylsulfonyl, ethylsulfonyl, n-propylsulfonyl, n-butylsulfonyl; branched ones such as isopropylsulfonyl, sec-butylsulfonyl, tert-butylsulfonyl, and the like. Of these, a methylsulfonyl group is preferred.
When the alkylsulfonyl group is substituted with a sulfo group or a carboxy group, specific examples thereof include a sulfo C1-C4 alkylsulfonyl group such as 2-sulfoethylsulfonyl, 3-sulfopropylsulfonyl, 4-sulfobutylsulfonyl and the like. A carboxy C1-C4 alkylsulfonyl group such as carboxymethylsulfonyl, 2-carboxyethylsulfonyl, 3-carboxypropylsulfonyl; and the like.

As the unsubstituted C1-C4 alkylthio group in R ¹ and R ² , both a straight chain and a branched chain are preferable, but a straight chain is more preferable. Specific examples include straight chain such as methylthio, ethylthio, n-propylthio and n-butylthio; branched chain such as isopropylthio, sec-butylthio and tert-butylthio; among them, the methylthio group is preferred.
When the alkylthio group is substituted with a sulfo group or a carboxy group, specific examples thereof include a sulfo C1-C4 alkylthio group such as 2-sulfoethylthio, 3-sulfopropylthio, 4-sulfobutylthio; Carboxy C1-C4 alkylthio groups such as methylthio, 2-carboxyethylthio, 3-carboxypropylthio; and the like.

Specific examples of the benzoyl group substituted with a sulfo group in R ¹ and R ² include 2-sulfobenzoyl, 3-sulfobenzoyl, 4-sulfobenzoyl and the like.

Specific examples of preferable R ¹ and R ² include a hydrogen atom, a chlorine atom, carboxy, sulfo, methyl, ethyl, methoxy, ethoxy, 2-hydroxyethoxy, carboxymethoxy, 2-carboxyethoxy, methylamino, ethylamino, 2 -Hydroxyethylamino, 2-sulfopropoxy, 3-sulfopropoxy, 4-sulfobutoxy, 2-sulfoethylamino, 3-sulfopropylamino, 2-carboxyethylamino, dimethylamino, diethylamino, 2,2'-dihydroxydiethylamino 2,2′-dicarboxydiethylamino, 3,3′-disulfodipropylamino, acetylamino, 3-carboxypropanoylamino, 4-hydroxybutanoylamino, N′-carboxymethylureido, N′-2- Sulfoethylureido, 4 -Sulfophenylamino, 2,4-disulfophenylamino, 2,5-dicarboxyphenylamino, benzoylamino, 3-sulfobenzoylamino, 2-carboxybenzoylamino, phenylsulfonylamino, 4-methylphenylsulfonylamino, 4 -Nitrophenylsulfonylamino, 3-sulfophenylsulfonylamino, 4-carboxyphenylsulfonylamino, methylsulfonyl, ethylsulfonyl, sulfopropylsulfonyl, carboxyethylsulfonyl, methylthio, ethylthio, propylthio, butylthio, 3-sulfopropylthio, 2- Carboxyethylthio, benzoyl and the like, more preferably hydrogen atom, fluorine atom, chlorine atom, sulfo, carboxy, methoxy, methylcarbonylamino (acetyl) 3-sulfopropylsulfonyl, 2-carboxyethylsulfonyl, methylsulfonyl, 3-sulfopropylthio, 2-carboxyethylthio, methylthio, more preferably hydrogen atom, chlorine atom, sulfo, carboxy, methoxy, methylcarbonylamino , Methylsulfonyl, methylthio.

R ³ represents a hydrogen atom, a methyl group, or a carboxy group. R ³ is preferably a methyl group or a carboxy group, and more preferably a methyl group.

R ⁴ represents a sulfo group or a carboxy group, both of which are preferred. These substitution positions are not particularly limited. When the substitution position of the amino group on the benzene ring substituted by R ⁴ is 1-position and the substitution position of the carboxylic acid amide is 2-position, substitution is made at the 4-position or 5-position. Is preferred. Further, it is more preferable to substitute at the 4-position if R ⁴ is a sulfo group and to the 5-position if it is a carboxy group.

In the above R ^{1 to} R ⁴ , compounds in which preferable ones are combined are more preferable, and compounds in which more preferable ones are combined are more preferable. The same applies to combinations of more preferable ones.

  The compound represented by the above formula (1) and its tautomer exist also as a free acid or a salt thereof. Examples of the salt of the compound represented by the above formula (1) and its tautomer include salts with inorganic or organic cations. Specific examples of the inorganic cation salt include alkali metal salts such as lithium, sodium, potassium and the like. Moreover, as an organic cation, although the quaternary ammonium salt represented, for example by following formula (6) is mentioned, It is not limited to these.

In formula (6) ^represents a Z 1 to Z ⁴ each independently represent a hydrogen atom, a C1-C4 alkyl group, hydroxy C1-C4 alkyl group, or hydroxy C1-C4 alkoxy C1-C4 alkyl group. ]

Here, examples of the C1-C4 alkyl group in Z ^{1 to} Z ⁴ include methyl, ethyl and the like, and examples of the hydroxy C1-C4 alkyl group include hydroxymethyl, hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 4-hydroxybutyl, 3-hydroxybutyl, 2-hydroxybutyl and the like, and examples of the hydroxy C1-C4 alkoxy C1-C4 alkyl group include hydroxyethoxymethyl, 2-hydroxyethoxyethyl, 3- (hydroxyethoxy) propyl, 3- (hydroxyethoxy) butyl, 2- (hydroxyethoxy) butyl and the like can be mentioned.

  Preferred examples of the salt include sodium, potassium, lithium, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, a salt of triisopropanolamine, and an ammonium salt. Of these, lithium, sodium, potassium, and ammonium salts are particularly preferred.

The compound represented by the above formula (1) of the present invention can be produced, for example, as follows. In addition, R ^{1 to} R ⁴ used as appropriate in the following formulas (A) to (E) represent the same meaning as in the above formula (1).
With reference to the example described in US Pat. No. 3,150,136, a compound represented by the following formula (A) and a compound represented by the following formula (B) can be reacted to obtain a cyclized product (C). For compounds in which R ⁴ is represented by a sulfo group, cyclization in which R ⁴ in formula (C) is represented by a hydrogen atom using a compound in which R ⁴ in formula (A) is represented by a hydrogen atom After synthesizing the compound, the compound represented by the formula (C) is preferably sulfonated with fuming sulfuric acid to induce cyclized product (C) in which R ⁴ is converted to a sulfo group ( R represents a methyl group, an ethyl group, or the like.

  Subsequently, aminobenzenesulfonic acids represented by the following formula (E) are diazotized by a conventional method, and a coupling reaction is performed with the previously obtained formula (C) at 10 to 30 ° C. and pH 7 to 11, The water-soluble azo compound of the present invention represented by the above formula (1) can be obtained.

Examples of the compound represented by the above formula (A) include carboxy derivatives such as 4-carboxyanthranilic acid hydrazide, anthranilic acid hydrazide, and the like. These hydrazides can be easily synthesized by reacting the corresponding esters of anthranilic acids with hydrazine such as an 80% aqueous hydrazine solution.
Examples of the compound represented by the above formula (B) include methyl acetoacetate, diethyl sodium oxalate and the like, and some are commercially available.
Examples of the compound represented by the above formula (E) include orthonilic acid, aniline-2,4-disulfonic acid, aniline-2,5-disulfonic acid, 4-anisidine-2-sulfonic acid, acetylmethamic acid, Acetyl paramic acid, 4-chloroaniline-2-sulfonic acid, 5-chloroaniline-2-sulfonic acid, 4,5-dichloroaniline-2-sulfonic acid, 5-fluoroaniline-2-sulfonic acid, 3-amino -4-sulfo-6-chlorobenzoic acid, 4-methylthioaniline-2-sulfonic acid, 5-methylthioaniline-2-sulfonic acid, 4-methylsulfonylaniline-2-sulfonic acid, 5-methylsulfonylaniline-2- Sulfonic acid, preferably aniline-2,4-disulfonic acid, aniline-2,5-disulfonic acid, 4-chloroaniline-2-sulfone Acid, 5-chloroaniline-2-sulfonic acid, 4,5-dichloroaniline-2-sulfonic acid, and 4-methylsulfonyl aniline-2-sulfonic acid can be given as specific examples.

  Next, preferred specific examples of the dye of the present invention are shown in Table 1 below. In Table 1, the sulfo group or carboxy group is represented in the form of a free acid. The present invention is not limited to these specific examples.

As will be apparent to those skilled in the art, the salt of the compound represented by the above formula (1) can be easily obtained by the following method or the like.
For example, the reaction solution in the final step in the synthesis reaction of the compound represented by the above formula (1), a wet cake containing the compound represented by the formula (1), or a dried product of the compound represented by the formula (1) Sodium salt of the compound represented by the above formula (1) can be obtained as a wet cake by adding salt to the aqueous solution in which the salt is dissolved and salting out, and filtering the precipitated solid.
Further, after dissolving the obtained sodium salt wet cake in water, an acid such as hydrochloric acid is added to adjust the pH appropriately, the precipitated solid is filtered, and the resulting solid is acidified with water or hydrochloric acid By washing with water or the like, inorganic salts contained as impurities, such as sodium chloride and sodium sulfate, can be removed, and the free acid of the compound represented by the above formula (1) or the formula (1) It is also possible to obtain a mixture of a free acid in which a part of the represented compound is a sodium salt and a sodium salt.
Furthermore, while stirring the wet cake of the free acid of the compound represented by the formula (1) with water, for example, an inorganic base such as potassium hydroxide, lithium hydroxide, aqueous ammonia, or the above formula (6) The corresponding potassium salt, lithium salt, ammonium salt, or quaternary ammonium salt can be obtained by adding an organic base such as a hydroxide of the compound to make it alkaline. By limiting the number of moles of the above-mentioned salt to the number of moles of free acid, it is possible to prepare, for example, a mixed salt of lithium and sodium, and further a mixed salt of lithium, sodium, and ammonium. It is.
Examples of the inorganic base include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate, ammonium hydroxide ( Ammonia water) or the like is used.
Examples of the organic base include, for example, quaternary ammonium salts represented by the above formula (6), for example, salts of alkanolamines such as diethanolamine and triethanolamine, but are not limited thereto.
The salt of the compound represented by the above formula (1) may change the physical properties such as solubility or the ink performance when used as an ink depending on the type of the salt. For this reason, it is also preferable to select the type of salt according to the intended ink performance.

The dyes of the present invention are suitable for the dyeing of natural and synthetic fiber materials or blends, and also for the production of writing inks and in particular ink jet recording ink compositions.
The reaction liquid containing the water-soluble azo compound of the present invention [for example, the reaction liquid before adding 800 parts of acetone in (Step 3) of Example 1 described later] or the like is directly used for the production of the ink composition of the present invention. You can also However, the compound can be isolated from the reaction solution by, for example, crystallization, spray drying or the like and then dried as necessary, and an ink composition can be prepared using the obtained compound. 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 2%, based on the total mass of the ink composition, using the water-soluble azo compound of the present invention as a coloring matter. 8% by mass is contained.

  In the ink composition of the present invention, the compound represented by the above formula (1) or a tautomer thereof is added to an aqueous medium such as water and, if necessary, a water-soluble organic solvent (an organic solvent miscible with water). Dissolved and further added with an ink adjusting agent as required. When this ink composition is used as an ink for an ink jet printer, it is preferable to use a metal cation chloride contained as an impurity, such as sodium chloride, sulfate, eg, a low content of inorganic impurities such as sodium sulfate. preferable. In this case, for example, the total content of sodium chloride and sodium sulfate is about 1% by mass or less in the total mass of the water-soluble azo compound of the present invention, and the lower limit is not more than the detection limit of the detection instrument, that is, 0% by mass. Good. In order to produce the compound having a small amount of inorganic impurities, for example, a desalting treatment may be performed by a known method using a reverse osmosis membrane. As another method, a dried product or wet cake of the compound of the present invention or a salt thereof is suspended and purified by stirring in a mixed solvent of alcohol such as methanol and water, and the solid is collected by filtration and dried. Desalting treatment is possible.

  The ink composition of the present invention is prepared using water as a medium, and may contain a water-soluble organic solvent, as necessary, within a range that does not impair the effects of the present invention. The water-soluble organic solvent may have the same function as a dye solubilizer, a drying inhibitor (wetting agent), a viscosity modifier, a penetration accelerator, a surface tension modifier, an antifoaming agent, and the like. It is preferable to contain it in the product. Other ink preparation agents include, for example, antiseptic / antifungal agents, pH adjusting agents, chelating reagents, rust preventing agents, UV absorbers, viscosity adjusting agents, dye dissolving agents, antifading agents, emulsion stabilizers, surface tension adjusting agents. And known additives such as antifoaming agents, dispersants, and dispersion stabilizers. The content of the water-soluble organic solvent is 0 to 60% by mass, preferably 10 to 50% by mass, and the ink preparation agent is 0 to 20% by mass, preferably 0 to 15% by mass, based on the entire ink. % Should be used. The remainder other than the above is water.

  Examples of water-soluble organic solvents that can be used in the present invention include C1-C4 alkanols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, and tert-butanol; N, N-dimethyl Amides such as formamide and N, N-dimethylacetamide; 2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethylimidazolidin-2-one, 1,3-dimethylhexahydropyrimido-2-one Heterocyclic ketones such as: ketones such as acetone, methyl ethyl ketone, 2-methyl-2-hydroxypentan-4-one or keto alcohols; cyclic ethers such as tetrahydrofuran, dioxane; ethylene glycol, 1,2- or 1,3- Propylene glycol, 1,2- or 1,4-butylene Mono, oligo, or polyalkylene glycols having C2-C6 alkylene units such as coal, 1,6-hexylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, thiodiglycol Or thioglycol; polyol (triol) such as glycerin, hexane-1,2,6-triol; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether (butyl carbitol) , Triethylene glycol monomethyl ether, triethylene glycol monoe C1-C4 monoalkyl ethers of polyhydric alcohols such as ethers; .gamma.-butyrolactone, dimethyl sulfoxide and the like.

  Preferred as the water-soluble organic solvent are isopropanol, glycerin, mono, di, or triethylene glycol, dipropylene glycol, 2-pyrrolidone, N-methyl-2-pyrrolidone, and butyl carbitol, more preferably Isopropanol, glycerin, diethylene glycol, 2-pyrrolidone, N-methyl-2-pyrrolidone, and butyl carbitol. These water-soluble organic solvents are used alone or in combination.

Examples of antiseptic / antifungal agents include organic sulfur, organic nitrogen sulfur, organic halogen, haloallylsulfone, iodopropargyl, N-haloalkylthio, benzothiazole, nitrile, pyridine, 8- Oxyquinoline, isothiazoline, dithiol, pyridine oxide, nitropropane, organotin, phenol, quaternary ammonium salt, triazine, thiadiazine, anilide, adamantane, dithiocarbamate, brominated indanone And benzyl bromacetate compounds.
Examples of the organic halogen compound include sodium pentachlorophenol, examples of the pyridine oxide compound include sodium 2-pyridinethiol-1-oxide, and examples of the isothiazoline compound include 1,2-benzisothiazoline. -3-one, 2-n-octyl-4-isothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one Examples thereof include magnesium chloride, 5-chloro-2-methyl-4-isothiazolin-3-one calcium chloride, and 2-methyl-4-isothiazolin-3-one calcium chloride.
Other antiseptic / antifungal agents include sodium acetate, sodium sorbate, sodium benzoate and the like. Other specific examples of the antiseptic / antifungal agent include, for example, trade names Proxel GXL (S) and Proxel XL-2 (S) manufactured by Avecia.

  As the pH adjuster, any substance can be used as long as it can control the pH of the ink within the range of 6.0 to 11.0 for the purpose of improving the storage stability of the ink. For example, alkanolamines such as diethanolamine and triethanolamine; hydroxides of alkali metals such as lithium hydroxide, sodium hydroxide and potassium hydroxide; ammonium hydroxides; or alkali metals such as lithium carbonate, sodium carbonate and potassium carbonate Examples of the carbonate include aminosulfonic acid such as taurine.

  Examples of the chelating reagent include sodium ethylenediaminetetraacetate, disodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate, sodium uracil diacetate, and the like.

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

  Examples of the ultraviolet absorber include benzophenone compounds, benzotriazole compounds, cinnamic acid compounds, triazine compounds, and stilbene compounds. Further, a compound that absorbs ultraviolet rays typified by a benzoxazole-based compound and emits fluorescence, a so-called fluorescent brightener can also be used.

  Examples of the viscosity modifier include water-soluble polymer compounds in addition to water-soluble organic solvents, such as polyvinyl alcohol, cellulose derivatives, polyamines, and polyimines.

  Examples of the dye solubilizer include urea, ε-caprolactam, ethylene carbonate, and the like. Of these, urea is preferably used.

  The anti-fading agent is used for the purpose of improving image storage stability. As the antifading agent, various organic and metal complex antifading agents can be used. Examples of organic anti-fading agents include hydroquinones, alkoxyphenols, dialkoxyphenols, phenols, anilines, amines, indanes, chromans, alkoxyanilines, heterocycles, etc. Includes nickel complexes and zinc complexes.

  Examples of the surface tension adjusting agent include surfactants, and examples include anionic surfactants, amphoteric surfactants, cationic surfactants, and nonionic surfactants.

  Examples of anionic surfactants include alkyl sulfocarboxylates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, N-acyl amino acids and salts thereof, N-acyl methyl taurate, alkyl sulfate polyoxyalkyl ethers 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, diethylsulfosuccinate Salt, diethyl hexyl sulphosuccinate, dioctyl sulphosuccinate and the like.

  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, and other imidazoline derivatives. Etc.

  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 -1-hexyne-3-acetylene glycol (alcohol) based such ol. Other specific examples include, for example, trade name Surfinol 104, 82, 465, Olphine STG manufactured by Nissin Chemical.

  As the antifoaming agent, a highly oxidized oil type, a glycerin fatty acid ester type, a fluorine type, a silicone type compound or the like is used as necessary.

  These ink preparation agents are used alone or in combination. The surface tension of the ink composition of the present invention is usually 25 to 70 mN / m, more preferably 25 to 60 mN / m. Further, the viscosity of the ink composition of the present invention is preferably 30 mPa · s or less, and more preferably adjusted to 20 mPa · s or less.

  In order to produce the ink composition of the present invention, there is no particular limitation on the order of dissolving each agent such as an additive. In preparing the composition, the water to be used is preferably one having few impurities such as ion exchange water and distilled water. Furthermore, if necessary, microfiltration may be performed using a membrane filter or the like to remove impurities. In particular, when it is used as an ink for an ink jet printer, it is preferable to perform microfiltration. The pore diameter of the filter for performing microfiltration is usually 1 to 0.1 μm, preferably 0.5 to 0.1 μm.

  The ink composition containing the water-soluble azo compound of the present invention is suitable for use in printing, copying, marking, writing, drawing, stamping, or recording (printing), particularly in inkjet recording. In addition, the ink composition of the present invention is less likely to cause precipitation of solid pigments even by drying in the vicinity of the nozzles of an inkjet printer, and for this reason, clogging of the printer head is also unlikely to occur. Furthermore, when the ink composition of the present invention is used for ink jet recording, a high-quality, high-color density, clear yellow print having good resistance to water, light, ozone gas, friction, etc. is obtained. It is done.

  In some inkjet printers, two types of ink, high density ink and low density ink, are loaded into one printer for the purpose of supplying a high-definition image. In that case, a high-concentration ink composition and a low-concentration ink composition may be prepared using the water-soluble azo compound of the present invention as a pigment, and these may be used as an ink set. Moreover, you may use this compound only for either one. Moreover, you may use together the water-soluble azo compound of this invention, and a well-known yellow pigment | dye. In addition, the coloring matter of the present invention can be used for toning of other colors, for example, black ink, or for mixing with a magenta coloring matter or a cyan coloring matter to prepare a red ink or a green ink.

  The colored product of the present invention is a substance colored with the water-soluble azo compound of the present invention or an ink composition containing the compound. There are no particular restrictions on the material of the colored body, for example, information transmission sheets such as paper and film, fibers and fabrics (cellulose, nylon, wool, etc.), leather, base materials for color filters, etc. Anything is acceptable and not limited to these. Examples of the coloring method include a printing method such as a dip dyeing method, a textile printing method, and screen printing, an ink jet recording method using an ink jet printer, and the ink jet recording method is preferable.

The information transmission sheet is preferably a surface-treated sheet, specifically, a sheet such as paper, synthetic paper, or film provided with an ink receiving layer. The ink receiving layer is formed by, for example, impregnating or coating the base material with a cationic polymer; inorganic fine particles capable of absorbing pigments in inks such as porous silica, alumina sol, and special ceramics are hydrophilic such as polyvinyl alcohol and polyvinyl pyrrolidone. A method of coating the surface of the base material together with the conductive polymer;
Those provided with such an ink receiving layer are usually called ink jet exclusive paper, ink jet exclusive film, glossy paper, gloss film and the like.
Among these, the porous silica, alumina sol, special ceramics, etc. mentioned above are applied to the substrate surface because they are easily affected by gases having an oxidizing action in the air, that is, ozone gas and nitrogen oxide gas. This is a special inkjet paper.
An example of a typical commercially available paper as an exclusive inkjet paper is Canon Inc., trade name Professional Photo Paper, Super Photo Paper, and Matt Photo Paper; Seiko Epson Corporation trade name Photo Paper Crispia ( High gloss), photo paper (gloss), photo matte paper; manufactured by Nippon Hewlett-Packard Co., Ltd., trade name Advanced Photo Paper (gloss); manufactured by Fuji Film Co., Ltd., trade name photo finish photo finish Pro;
Since the ink composition of the present invention has excellent resistance to the above-mentioned oxidizing gas, particularly ozone gas, it can provide an excellent recorded image with little discoloration even when recording on such a recording material. It can also be used for plain paper.

In order to record on a recording material by the ink jet recording method of the present invention, for example, a container filled with the above ink composition may be loaded at a predetermined position of an ink jet printer and recorded on the recording material by a normal method. . In the ink jet recording method of the present invention, magenta ink, cyan ink, and, if necessary, green ink, blue (or violet) ink, red ink, black ink and the like can be used in combination with the ink composition of the present invention. In this case, the inks of the respective colors are injected into the respective containers, and these containers are used in a predetermined position of the ink jet printer.
Some inkjet printers use, for example, a piezo method using mechanical vibration; a bubble jet (registered trademark) method using bubbles generated by heating; and the like. The ink jet recording method of the present invention can be used by any method.

The ink composition of the present invention has a clear yellow color, and particularly has high clarity and color density of an image recorded on ink jet dedicated paper or glossy paper, and has a hue suitable for the ink jet recording method. Further, the fastness of the recorded image, particularly light resistance and ozone gas resistance are very high.
The ink composition of the present invention does not precipitate or separate during storage, and has extremely high storage stability. Further, when the ink composition of the present invention is used for ink jet recording, solid precipitation due to drying of the ink composition in the vicinity of the nozzle is very unlikely to occur, and the ejector (ink head) is not blocked. The ink composition of the present invention uses a continuous ink jet printer and has physical properties whether it is used by recirculating ink at a relatively long time interval or intermittent use by an on-demand ink jet printer. Does not change.

Hereinafter, the present invention will be described more specifically with reference to examples. In the text, “parts” and “%” are based on mass unless otherwise specified, and the reaction temperature is also the internal temperature. Operations such as each reaction and crystallization in the examples were carried out with stirring unless otherwise specified.
In addition, (lambda) max (maximum absorption wavelength) of each compound synthesize | combined showed the measured value in the range of 300 nm-800 nm in pH 7-8 aqueous solution. Moreover, although the water-soluble azo compounds of the present invention obtained in the examples are all sodium salts, their chemical structural formulas are shown as free acids for convenience. However, as described above, a free acid or an alkali metal salt other than a sodium salt can be easily obtained by using an appropriate method, and the present invention is not limited to this example.

[Example 1]
(Process 1)
38 parts of anthranilic hydrazide was added to 100 parts of methanol, followed by 30 parts of methyl acetoacetate. After stirring at 15 ° C. to 35 ° C. for 1 hour, 25 parts of sodium carbonate was added. After stirring at 35 ° C. to 45 ° C. for 5 hours, 100 parts of water was added and stirred for 1 hour, and the precipitated solid was collected by filtration to obtain 200 parts of a compound represented by the following formula (8) as a wet cake. . This was dried with a hot air dryer at 80 ° C. to obtain 40 parts of a compound represented by the following formula (8).

(Process 2)
Subsequently, 40 parts of the compound represented by the formula (8) thus obtained was added to 88 parts of 20% fuming sulfuric acid, followed by stirring at 100 ° C. for 1 hour. This reaction solution was slowly added to 200 parts of ice water, and then stirred for 1 hour, and the precipitated solid was collected by filtration to obtain 90 parts of a compound represented by the following formula (9) as a wet cake.

(Process 3)
25.3 parts of aniline-2,5-disulfonic acid was dissolved in 200 parts of water while adjusting the pH to 6 with sodium hydroxide, and then 7.2 parts of sodium nitrite was added. This solution was added dropwise to 200 parts of 5% hydrochloric acid at 0 to 10 ° C. over 30 minutes, followed by stirring at 10 ° C. or lower for 1 hour to carry out a diazotization reaction to prepare a diazo reaction liquid.
On the other hand, the wet cake of the above formula (9) obtained earlier was added to 100 parts of water and adjusted to pH 10 using sodium hydroxide. The diazo reaction liquid prepared previously was added to this solution, and it stirred at 0-25 degreeC and pH 9-11 for 2 hours.
To the obtained reaction liquid, 800 parts of acetone was added and stirred at 20 to 25 ° C. for 1 hour. The precipitated solid was collected by filtration to obtain 120.0 parts of a wet cake. The wet cake was dried with a hot air dryer at 80 ° C. to obtain 40.0 parts of a water-soluble azo compound (λmax: 407.5 nm) of the present invention represented by the following formula (10).

[Example 2]
The same method as in Example 1 except that 25.3 parts of aniline-2,4-disulfonic acid was used instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1. Thus, 39.0 parts of the water-soluble azo compound of the present invention (λmax: 416.0 nm) represented by the following formula (11) was obtained.

[Example 3]
The same method as in Example 1, except that 20.3 parts of 4-anisidine-2-sulfonic acid was used instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1 Thus, 35.0 parts of the water-soluble azo compound (λmax: 401.5 nm) of the present invention represented by the following formula (12) was obtained.

[Example 4]
The same formula as in Example 1 except that 23.0 parts of acetylparamic acid was used instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1, and the following formula: 38.0 parts of the water-soluble azo compound of the present invention (λmax: 458.5 nm) represented by (13) were obtained.

[Example 5]
The same formula as in Example 1 except that 23.0 parts of acetylmethamic acid was used instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1, and the following formula: 38.0 parts of the water-soluble azo compound of the present invention (λmax: 403.5 nm) represented by (14) was obtained.

[Example 6]
A method similar to that of Example 1 except that 17.3 parts of alternanilic acid was used instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1, and the following formula (15 30.0 parts of a water-soluble azo compound of the present invention (λmax: 401.0 nm) represented by

[Example 7]
The same as Example 1 except that 20.9 parts of 4-chloroaniline-2-sulfonic acid was used instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1. By the method, 33.0 parts of the water-soluble azo compound (λmax: 440.0 nm) of the present invention represented by the following formula (16) was obtained.

[Example 8]
Example 2 with the exception of using 24.2 parts of 4,5-dichloroaniline-2-sulfonic acid instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1 In the same manner, 38.0 parts of the water-soluble azo compound of the present invention (λmax: 412.5 nm) represented by the following formula (17) was obtained.

[Example 9]
Example except that 25.2 parts of 5-amino-4-sulfo-2-chlorobenzoic acid were used instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1 In the same manner as in Example 1, 39.5 parts of the water-soluble azo compound (λmax: 408.5 nm) of the present invention represented by the following formula (18) was obtained.

[Example 10]
Similar to Example 1 except that 21.9 parts of 5-methylthioaniline-2-sulfonic acid were used instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1. By the method, 36.0 parts of the water-soluble azo compound of the present invention (λmax: 447.0 nm) represented by the following formula (19) was obtained.

[Example 11]
Similar to Example 1 except that 25.1 parts of 4-methylsulfonylaniline-2-sulfonic acid are used instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1. By the method, 37.0 parts of the water-soluble azo compound (λmax: 429.0 nm) of the present invention represented by the following formula (20) was obtained.

[Example 12]
(Process 1)
38 parts of anthranilic hydrazide was added to 100 parts of methanol, and then 60 parts of diethyl sodium oxalate were added and stirred at 15 ° C. to 35 ° C. for 1 hour, and then 25 parts of sodium carbonate was added. After stirring this reaction liquid at 35 ° C. to 45 ° C. for 5 hours, 100 parts of water was added and stirred for 1 hour, and the precipitated solid was collected by filtration to wet 200 parts of the compound represented by the following formula (21). Obtained as a cake. The obtained wet cake was dried with a hot air dryer at 80 ° C. to obtain 30 parts of a compound represented by the following formula (21).

(Process 2)
30 parts of the compound represented by the formula (21) thus obtained was added to 88 parts of 20% fuming sulfuric acid and stirred at 100 ° C. for 1 hour. The reaction solution was slowly added to 200 parts of ice water and then stirred for 1 hour, and the precipitated solid was collected by filtration to obtain 60 parts of a compound represented by the following formula (22) as a wet cake.

(Process 3)
25.3 parts of aniline-2,5-disulfonic acid was dissolved in 200 parts of water while adjusting the pH to 6 with sodium hydroxide, and then 7.2 parts of sodium nitrite was added. This solution was added dropwise to 200 parts of 5% hydrochloric acid at 0 to 10 ° C. over 30 minutes, followed by stirring at 10 ° C. or lower for 1 hour to carry out a diazotization reaction to prepare a diazo reaction liquid.
On the other hand, the wet cake of the above formula (22) obtained above was added to 100 parts of water and adjusted to pH 10 using sodium hydroxide. The diazo reaction liquid prepared previously was added to this solution, and it stirred at 0-25 degreeC and pH 9-11 for 2 hours.
To the obtained reaction liquid, 800 parts of acetone was added and stirred at 20 to 25 ° C. for 1 hour. The precipitated solid was collected by filtration to obtain 120.0 parts of a wet cake. The wet cake was dried with a hot air dryer at 80 ° C. to obtain 35.0 parts of a water-soluble azo compound (λmax: 408.0 nm) of the present invention represented by the following formula (23).

[Example 13]
(Process 1)
Add 58.5 parts of 2-aminoterephthalic acid-1-methyl ester to 20.0 parts of 80% aqueous hydrazine solution, stir at 70 ° C. to 80 ° C. for 8 hours, cool to 10 ° C. to 30 ° C. and filter. As a result, 70 parts of a compound represented by the following formula (24) was obtained as a wet cake.

  70 parts of the compound represented by the formula (24) thus obtained was added to 100 parts of methanol, and then 30 parts of methyl acetoacetate was added. After stirring at 15 ° C. to 35 ° C. for 1 hour, 25 parts of sodium carbonate was added. After stirring at 35 ° C. to 45 ° C. for 5 hours, 100 parts of water was added and stirred for 1 hour, and the precipitated solid was collected by filtration to obtain 200 parts of a wet cake. This was dried with a hot air dryer at 80 ° C. to obtain 40 parts of a compound represented by the following formula (25).

(Process 2)
25.3 parts of aniline-2,4-disulfonic acid was dissolved in 200 parts of water while adjusting the pH to 6 with sodium hydroxide, and then 7.2 parts of sodium nitrite was added. This solution was added dropwise to 200 parts of 5% hydrochloric acid at 0 to 10 ° C. over 30 minutes, followed by stirring at 10 ° C. or lower for 1 hour to carry out a diazotization reaction to prepare a diazo reaction liquid.
On the other hand, 40 parts of the compound represented by the formula (25) obtained earlier was added to 100 parts of water, and the pH was adjusted to 10 using sodium hydroxide. The diazo reaction liquid prepared previously was added to this solution, and it stirred at 0-25 degreeC and pH 9-11 for 2 hours.
To the obtained reaction liquid, 800 parts of acetone was added and stirred at 20 to 25 ° C. for 1 hour. The precipitated solid was collected by filtration to obtain 120.0 parts of a wet cake. This wet cake was dried with a hot air dryer at 80 ° C. to obtain 30.0 parts of a water-soluble azo compound (λmax: 425.5 nm) of the present invention represented by the following formula (26).

[Example 14]
Similar to Example 13 except that 25.1 parts 4-methylsulfonylaniline-2-sulfonic acid is used instead of 25.3 parts aniline-2,4-disulfonic acid used in (Step 2) of Example 13. By this method, 29.0 parts of the water-soluble azo compound of the present invention (λmax: 433.0 nm) represented by the following formula (27) was obtained.

[Examples 15 to 18]
[(A) Preparation of ink]
Using the water-soluble azo compound of the present invention obtained in Examples 1, 2, 6, and 8 as a dye component, the components are mixed at the composition ratio shown in Table 2 below, and the ink composition of the present invention is mixed. Each was filtered through a 0.45 μm membrane filter to remove impurities, and an ink was obtained. The water was ion-exchanged water, adjusted with an aqueous sodium hydroxide solution so that the pH of the ink composition was about 9, and then added so that the total amount was 100 parts. The ink preparations using the compounds obtained in Examples 1, 2, 6, and 8 are Examples 15, 16, 17, and 18, respectively.

[Comparative Example 1]
In place of the azo compound obtained in each implementation as a dye component, C.I. I. A comparative ink was prepared in the same manner as in each Example except that Acid Yellow 17 was used. This is referred to as Comparative Example 1.

[Comparative Example 2]
In place of the azo compound obtained in each implementation as a dye component, C.I. I. A comparative ink was prepared in the same manner as in each Example except that Acid Yellow 23 was used. This is referred to as Comparative Example 2.

[(B) Inkjet print]
Inkjet recording was performed on inkjet-dedicated paper using a product name: PIXUS ip4100 manufactured by Canon as an inkjet printer. The inkjet paper used is Nippon Hewlett-Packard Co., Ltd., Advanced Photo Paper (Glossy) and Fuji Photo Film Co., Ltd., and Photographic Finishing Pro. During ink jet recording, an image pattern was prepared so that the reflection density could be obtained in several levels of gradation, and yellow prints colored with the inks of Examples 15 to 18 and Comparative Examples 1 and 2 were obtained. Inkjet paper manufactured by Nippon Hewlett-Packard Co., Ltd., printed using Advanced Photo Paper (gloss), is printed matter 1, and is made using Fuji Photo Film Co., Ltd. The printed matter 2 is assumed.
In the light resistance test and the ozone gas resistance test, the reflection density was measured in a portion where the reflection density D value of each printed matter before the test was in the range of 0.7 to 1.0. The reflection density was measured using a color measurement system (SpectroEye, manufactured by GretagMacbeth) under the conditions of DIN, viewing angle 2 °, and light source D65 as a density reference.
Various test methods for recorded images and evaluation methods for test results are described below.

[(C) Xenon light resistance test]
Print pieces 1 and 2 printed on the inkjet paper are installed in a holder, and a xenon weatherometer XL75 (manufactured by Suga Test Instruments Co., Ltd.) is used. Irradiated at 36 W / square meter for 96 hours.
After the test, the color density is measured using a colorimetry system, and the residual ratio of the reflection density is calculated by (reflection density after test / reflection density before test) × 100 (%) and evaluated in three stages. did.
Dye remaining rate is 80% or more ······· Dye remaining rate is 70% or more and less than 80% ···
Dye remaining rate is less than 70%
The results are shown in Tables 3 and 4.

[(D) Ozone gas resistance test]
Print pieces 1 and 2 printed on inkjet paper are left in an ozone weather meter (Suga Test Instruments Co., Ltd.) for 16 hours in an environment with an ozone concentration of 5 ppm, humidity of 60% RH, and temperature of 24 ° C. Then, the reflection density was measured using the above colorimetric system. After the measurement, the residual ratio of the reflection density was calculated by (reflection density after test / reflection density before test) × 100 (%) and evaluated in three stages.
Dye remaining rate is 90% or more ······· Dye remaining rate is 80% or more and less than 90% ···
Dye remaining rate is less than 80%
The results are shown in Tables 3 and 4.

Table 3 (C) Xenon Light Resistance and (D) Ozone Gas Resistance Test Results for Printed Material 1

Table 4 (C) Xenon Light Resistance and (D) Ozone Gas Resistance Test Results for Printed Material 2

  As is clear from the results in Tables 3 and 4, it was found that in each of the tests using the printed materials 1 and 2, each example was much more excellent in ozone gas resistance than each comparative example. Further, in regard to xenon light resistance, Comparative Example 1 using the printed matter 2 showed relatively good results, but other than that, each Example is far superior to each Comparative Example. Became clear.

[Example 19]
An ink was obtained in the same manner as in “(A) Preparation of ink” except that the compound obtained in Example 13 was used instead of the compound obtained in Examples 1, 2, 6, and 8. . This ink was prepared as Example 19.

[Comparative Example 3]
Instead of the compounds obtained in Examples 1, 2, 6, and 8, a comparative compound represented by the following formula (28) was used, and the same as “(A) Preparation of ink” above. Thus, a comparative ink was obtained. This ink preparation is referred to as Comparative Example 3. In the compound of the formula (28), one of R ¹ and R ² in the formula (1) is a hydrogen atom and the other is a hydroxy group, and the present invention does not include the hydroxy group. It is a compound not included in the scope of the invention.
The compound for comparison represented by the following formula (28) is 2-aminophenol-4 instead of 25.3 parts of aniline-2,5-disulfonic acid used in (Step 3) of Example 1. Synthesis was carried out in the same manner as in Example 1 except that 25.0 parts of sulfonic acid was used to obtain 30.0 parts (λmax: 473 nm).

Each of the inks of Examples 15 to 19 and Comparative Examples 1 to 3 obtained as described above was manufactured by Fuji Photo Film Co., Ltd. Inkjet recording was performed to obtain a printed matter 3 recorded with the inks of the examples and comparative examples.
For each printed matter 3 obtained, the evaluation test of the recorded image described in (E) and (F) below was performed using the same colorimetric conditions as described above.

[(E) Xenon light resistance test]
This test was conducted under the same test conditions as the above “(C) Xenon light resistance test” except that the printed matter 3 was used as a printed piece and the evaluation criteria were changed as follows.
Dye remaining rate is 80% or more ...
Dye remaining ratio is 65% or more and less than 80% ・ ・ ・ △
Dye remaining rate is less than 65%
The test results are shown in Table 5 below.

[(F) Ozone gas resistance test]
This test was conducted under the same test conditions as the above “(D) Ozone gas resistance test” except that the printed matter 3 was used as a printed piece, the ozone concentration was changed to 10 ppm, and the evaluation criteria were changed as follows.
Dye remaining rate is 85% or more ...
Dye residual ratio is 40% or more and less than 85%.
Dye remaining rate is less than 40%
The test results are shown in Table 5 below.

Table 5 (E) xenon light resistance and (F) ozone gas resistance test results of printed matter 3

  As is clear from the results in Table 5, each example was found to be far superior to each comparative example in both the xenon light resistance and ozone resistance tests.

  From the above results, it was found that the water-soluble azo compound of the present invention is suitable for preparing an ink composition for inkjet recording, and is extremely excellent in various fastness properties, particularly light resistance and ozone gas resistance. . Furthermore, the azo compound of the present invention has a high concentration and high saturation, and has a good and clear hue. From these characteristics, it is clear that the azo compound of the present invention is a very useful compound as various dyes for recording ink, particularly as a yellow dye for inkjet ink.

Claims (14)

A water-soluble azo compound represented by the following formula (1), a tautomer thereof, or a salt thereof.

[In Formula (1),
R ¹ and R ² are each independently a hydrogen atom; a fluorine atom; a chlorine atom; a sulfo group; a carboxy group; a sulfamoyl group; a carbamoyl group; an unsubstituted C1-C4 alkyl group; a hydroxy group, an unsubstituted C1-C4 alkoxy group, A C1-C4 alkoxy group substituted by a hydroxy C1-C4 alkoxy group, a sulfo group, or a carboxy group, or an unsubstituted C1-C4 alkoxy group; a mono- or di-C1- substituted by a hydroxy group, a sulfo group, or a carboxy group A C4 alkylamino group, or an unsubstituted mono- or di-C1-C4 alkylamino group; a C1-C4 alkylcarbonylamino group substituted with a hydroxy group or a carboxy group, or an unsubstituted C1-C4 alkylcarbonylamino group; a hydroxy group, a sulfo group Group or carboxy group A substituted N′-C1-C4 alkylureido group or an unsubstituted N′-C1-C4 alkylureido group; the benzene ring is a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or a carboxy group; A substituted phenylamino group or an unsubstituted phenylamino group; a benzoylamino group in which the benzene ring is substituted with a chlorine atom, an unsubstituted C1-C4 alkyl group, a nitro group, a sulfo group, or a carboxy group, or an unsubstituted benzoylamino group Group; phenylsulfonylamino group substituted with chlorine atom, unsubstituted C1-C4 alkyl group, nitro group, sulfo group, or carboxy group, or unsubstituted phenylsulfonylamino group; substituted with sulfo group or carboxy group C1-C4 alkylsulfonyl group, or unsubstituted C1-C Represents; alkylsulfonyl group; a sulfo group or a C1-C4 alkylthio group substituted by a carboxy group, or unsubstituted C1-C4 alkylthio group; or, a benzoyl group substituted by a sulfo group, or unsubstituted benzoyl group
R ³ represents a hydrogen atom, a methyl group, or a carboxy group,
R ⁴ represents a sulfo group or a carboxy group. ] R ¹ and R ² are each independently hydrogen atom; fluorine atom; chlorine atom; sulfo group; carboxy group; unsubstituted C1-C4 alkoxy group; unsubstituted C1-C4 alkylcarbonylamino group; substituted with sulfo group or carboxy group A substituted C1-C4 alkylsulfonyl group, or an unsubstituted C1-C4 alkylsulfonyl group; or a C1-C4 alkylthio group substituted with a sulfo group or a carboxy group, or an unsubstituted C1-C4 alkylthio group;
The water-soluble azo compound according to claim 1, or a tautomer thereof, or a salt thereof, wherein R ³ is a methyl group or a carboxy group. R ¹ and R ² are each independently a hydrogen atom; a chlorine atom; a sulfo group; a carboxy group; an unsubstituted C1-C4 alkoxy group; an unsubstituted C1-C4 alkylcarbonylamino group; an unsubstituted C1-C4 alkylsulfonyl group; or An unsubstituted C1-C4 alkylthio group;
The water-soluble azo compound according to claim 1, or a tautomer thereof, or a salt thereof, wherein R ³ is a methyl group or a carboxy group. The water-soluble azo compound according to any one of claims 1 to 3, or a tautomer thereof, or a salt thereof, wherein R ³ is a methyl group. The water-soluble azo compound or a tautomer thereof, or a salt thereof according to any one of claims 1 to 4, wherein R ¹ is a sulfo group and R ² is a hydrogen atom.   An ink composition comprising the water-soluble azo compound according to any one of claims 1 to 5 or a tautomer thereof, or a salt thereof as a coloring matter.   The ink composition according to claim 6, further comprising a water-soluble organic solvent.   The ink composition according to claim 6 or 7, which is for inkjet recording.   An ink jet recording method for performing recording by using the ink composition according to any one of claims 6 to 8 as ink, and ejecting ink droplets of the ink in accordance with a recording signal to adhere to the recording material.   The inkjet recording method according to claim 9, wherein the recording material is an information transmission sheet.   The inkjet recording method according to claim 10, wherein the information transmission sheet is a sheet having an ink receiving layer containing a porous white inorganic substance.   Colored with the water-soluble azo compound according to any one of claims 1 to 5, or a tautomer thereof, or a salt thereof, or the ink composition according to any one of claims 6 to 8. Colored body.   The colored body according to claim 12, wherein coloring is performed by an ink jet printer.   An inkjet printer loaded with a container containing the ink composition according to claim 6.