JP2005036222A - Azo compound, water-base ink composition and colored material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a black compound suitable for use in inkjet recording, writing utensil and excellent in ozone gas resistance, light fastness, moisture resistance and color rendering properties, storage stability as a recording liquid, and to provide an ink composition comprising the same. <P>SOLUTION: The invention relates to an ink composition comprising an azo compound represented by formula (1) or a salt of the same. (In the formula R<SP>1</SP>-R<SP>6</SP>are each arbitrary substituents, A and B are each a single bond, wherein the substituted position of the bonding A is 2- or 3-position and the substituted position of the bonding B is 2'- or 3'-position, l is 1 or 2, m and n are each 0 or 1. The position of substitution of (SO<SB>3</SB>H)<SB>m</SB>is 3 or 4 position, and the substituted position of a (SO<SB>3</SB>H)<SB>n</SB>is 3'- or 4'-position). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a novel water-soluble azo compound or a salt thereof, an aqueous ink composition containing these, and a colored product thereby.

The pigment exhibiting black is used not only for printing character information but also for color images. However, there are many technical difficulties in developing pigments that have a neutral hue and a high density of black, and a great deal of research and development has been carried out, but few have sufficient performance. For this reason, a variety of pigments are mixed to form a black color. However, the development of pigments that exhibit a neutral black color with a high concentration by one type is the most strongly demanded technical issue. is there.
A recording method using an ink jet printer, which is one of the representative methods among various color recording methods, generates ink droplets and attaches them to various recording materials (paper, film, fabric, etc.) for recording. Is what you do. This method has been spreading rapidly in recent years due to the fact that the recording head and the recording material do not contact each other and is quiet with little sound generation, and is easy to downsize and speed up. Expected. Conventionally, water-based inks in which water-soluble dyes are dissolved in an aqueous medium have been used as inks such as fountain pens, felt-tip pens, and ink-jet recording inks. In order to prevent clogging of ink, a water-soluble organic solvent is generally added. Therefore, in these conventional inks, it is possible to provide a recording image having a sufficient density, no clogging of the pen tip and nozzles, good drying on the recording material, less bleeding, The storage stability is required to be excellent, and particularly, the solubility in water is high, and the solubility in a water-soluble organic solvent added to the ink is required. Further, the formed image is required to have image fastness such as water resistance, light resistance, ozone gas resistance and moisture resistance.
Ozone gas resistance, also called ozone resistance or gas resistance, is a phenomenon in which ozone gas with an oxidizing action that exists in the air reacts with dyes in the recording paper and discolors the printed image. It is resistance to. In addition to ozone gas, examples of the oxidizing gas having this kind of action include NOx and SOx. Among various oxidizing gases, ozone gas is considered to be a causative substance that further promotes the color fading phenomenon of ink jet recorded images, and ozone gas is used in an acceleration test for knowing the degree of ozone gas resistance. Such a discoloration and fading phenomenon caused by an oxidizing gas is characteristic of an ink jet image, so that improvement of ozone gas resistance has become a more important issue. Since this discoloration phenomenon is characteristic of an inkjet image, improvement of ozone gas resistance is a more important issue. In particular, the ink receiving layer provided on the surface of photographic image quality inkjet paper uses a porous material such as a white inorganic pigment to speed up ink drying and reduce bleeding at high image quality. In many cases, discoloration due to ozone gas is noticeable on such recording paper.
Further, the moisture resistance is resistance to a phenomenon that a dye in a recording material bleeds when the colored recording material is stored in a high humidity atmosphere. If there is a blur of the dye, the image quality is remarkably deteriorated particularly in an image requiring a high-definition image quality such as a photographic tone. Therefore, it is important to reduce such a blur as much as possible. Accordingly, moisture resistance is also an important issue required as an ink-jet dye, as with the above-described ozone gas resistance.
In the future, in order to expand the field of use of printing methods using ink, the ink composition used for inkjet recording and the colored bodies colored thereby will be further improved in water resistance, light resistance, moisture resistance and ozone gas resistance. There is a strong demand for improvement.
Various hues of ink are prepared from various dyes, of which black ink is an important ink used for both monocolor and full color images. Many dyes for these black inks have been proposed to date, but they have not yet been able to provide products that fully satisfy market demands. Many of the proposed dyes are diazo dyes, which have problems such as the hue being too shallow (reddish black), poor color rendering, poor water and moisture resistance, and insufficient ozone gas resistance. There is. Similarly, many azo metal-containing dyes that have been proposed have problems such as insufficient metal safety, environmental considerations, and insufficient ozone gas resistance, including metal ions. Trisazo dyes and tetraazo dyes with extended conjugated systems to deepen hues still have problems such as low hue concentration, poor water solubility and poor storage stability of aqueous solutions and inks, and insufficient ozone gas resistance. ing.
Examples of tetraazo compounds as azo compounds having a long conjugated system have been proposed in Patent Documents 1 to 4 and the like, but have not yet reached the supply of products that sufficiently satisfy the market demand as black ink components for inkjet. .
Japanese Patent Publication No. 61-18590 Japanese Patent Publication No. 7-42427 JP 7-138492 A JP-A-9-12910 International Publication WO00 / 43451 Pamphlet International Publication WO00 / 43453 Pamphlet

  The present invention has high solubility in a medium containing water as a main component, is stable even when a high-concentration dye aqueous solution and ink are stored for a long period of time, exhibits neutral black with no color, and prints of printed images. The object is to provide a black recording image having high concentration and excellent in moisture resistance, light resistance and ozone gas resistance, and to provide a black pigment and its ink composition that are easy to synthesize and inexpensive. .

（式（１）中、Ｒ¹からＲ⁶は任意の置換基であり、Ａ及びＢはそれぞれ単結合を示し、結合Ａの置換位置は２または３位、結合Ｂの置換位置は２'または３'位、ｌは１または２であり、ｍ及びｎは０または１である。（ＳＯ₃Ｈ）mの置換位置は３または４位であり、（ＳＯ₃Ｈ）nの置換位置は３'または４'位である。）を少なくとも１種を含有することを特徴とするインク組成物、
（２）式（１）において、Ｒ¹からＲ³が水素；ハロゲン原子；シアノ基；ヒドロキシ基；アミノ基；カルボキシル基；スルホ基；アルキル基若しくはフェニル基で置換されても良いスルファモイル基；リン酸基；ニトロ基；アシル基；フェニル基；ウレイド基；ヒドロキシ基若しくは（Ｃ１〜Ｃ４）アルコキシ基で置換されても良い（Ｃ１〜Ｃ４）アルキル基；ヒドロキシ基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基若しくはカルボキシル基で置換されても良い（Ｃ１〜Ｃ４）アルコキシ基；カルボキシル基若しくはスルホ基で更に置換されていても良いフェニル基によって置換されているアミノ基；アルキル基若しくはアシル基によって置換されているアミノ基であり、Ｒ⁴が水素；ヒドロキシ基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基若しくはカルボキシル基で置換されても良い（Ｃ１〜Ｃ４）アルキル基；アミノ基、アルキル基、アルコキシ基、カルボキシル基又はスルホ基で置換されていても良いフェニル基であり、Ｒ⁵及びＲ⁶が水素；スルホ基；アセチルアミノ基；ヒドロキシ基若しくは（Ｃ１〜Ｃ４）アルコキシ基で置換されても良い（Ｃ１〜Ｃ４）アルキル基；ヒドロキシ基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基若しくはカルボキシル基で置換されても良い（Ｃ１〜Ｃ４）アルコキシ基である（１）に記載のインク組成物、
（３）式（１）の化合物が下記式（１ａ）で表されるアゾ化合物またはその塩

（式（１ａ）において、Ｒ¹〜Ｒ³がスルホ基、カルボキシル基、メチル基またはメトキシ基、Ｒ⁵、Ｒ⁶が（Ｃ１〜Ｃ４）アルキル基；ヒドロキシ基またはスルホ基で置換されても良い（Ｃ１〜Ｃ４）アルコキシ基、Ｂの置換位置が２'または３'位である）
である（１）に記載のインク組成物、
（４）塩がリチウム塩、ナトリウム塩、カリウム塩、アンモニウム塩または一般式（２）で表されるアンモニウム塩である（１）から（３）のいずれか一項に記載のインク組成物、

（式（２）中、Ｚ¹、Ｚ²、Ｚ³、Ｚ⁴はそれぞれ独立に水素原子、アルキル基、ヒドロキシアルキル基またはヒドロキシアルコキシアルキル基を表す。）
（５）（１）から（４）のいずれか一項に記載のインク組成物を装填したインクジェットプリンタ、
（６）（５）に記載のインクジェットプリンタによって着色された着色体、
（７）式（１ｂ）で表されるアゾ化合物またはその塩、

（式（１ｂ）において、Ｒ¹からＲ³が水素；ハロゲン原子；シアノ基；ヒドロキシ基；アミノ基；カルボキシル基；スルホ基；アルキル基若しくはフェニル基で置換されても良いスルファモイル基；リン酸基；ニトロ基；アシル基；フェニル基；ウレイド基；ヒドロキシ基若しくは（Ｃ１〜Ｃ４）アルコキシ基で置換されても良い（Ｃ１〜Ｃ４）アルキル基；ヒドロキシ基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基若しくはカルボキシル基で置換されても良い（Ｃ１〜Ｃ４）アルコキシ基；カルボキシル基若しくはスルホ基で更に置換されていても良いフェニル基によって置換されているアミノ基；アルキル基若しくはアシル基によって置換されているアミノ基であり、Ｒ⁴が水素；ヒドロキシ基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基若しくはカルボキシル基で置換されても良い（Ｃ１〜Ｃ４）アルキル基；アミノ基、アルキル基、アルコキシ基、カルボキシル基又はスルホ基で置換されていても良いフェニル基であり、Ｒ⁵及びＲ⁶が水素；スルホ基；アセチルアミノ基；ヒドロキシ基若しくは（Ｃ１〜Ｃ４）アルコキシ基で置換されても良い（Ｃ１〜Ｃ４）アルキル基；ヒドロキシ基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基若しくはカルボキシル基で置換されても良い（Ｃ１〜Ｃ４）アルコキシ基である。結合Ａの置換位置は２または３位、Ｂの置換位置は２'または３'位、lは１または２であり、m及びnは０または１である。（ＳＯ₃Ｈ）mの置換位置は３または４位であり、（ＳＯ₃Ｈ）nの置換位置は３'または４'位である。）
に関する。 As a result of intensive studies to solve the problems as described above, the present inventors have reached the present invention. That is, the present invention
(1) An azo compound represented by the following formula (1) or a salt thereof

(In the formula (1), R ¹ to R ⁶ are optional substituents, A and B each represent a single bond, the substitution position of the bond A is 2 or 3, and the substitution position of the bond B is 2 ′ or 3 ′ position, l is 1 or 2, and m and n are 0 or 1. The substitution position of (SO ₃ H) m is the 3 or 4 position, and the substitution position of (SO ₃ H) n is 3 An ink composition characterized in that it contains at least one kind
(2) In the formula (1), R ¹ to R ³ are hydrogen, halogen atom, cyano group, hydroxy group, amino group, carboxyl group, sulfo group, sulfamoyl group which may be substituted with alkyl group or phenyl group, phosphorus An acid group; a nitro group; an acyl group; a phenyl group; a ureido group; a hydroxy group or a (C1-C4) alkyl group optionally substituted with a (C1-C4) alkoxy group; a hydroxy group, a (C1-C4) alkoxy group; (C1-C4) alkoxy group optionally substituted with a sulfo group or a carboxyl group; an amino group substituted with a phenyl group which may be further substituted with a carboxyl group or a sulfo group; substituted with an alkyl group or an acyl group and an amino group are, R ⁴ is hydrogen; hydroxy group, (C1 -C4) alkoxy group, a sulfo group Properly which may be substituted with a carboxyl group (C1 -C4) alkyl group; an amino group, an alkyl group, an alkoxy group, a phenyl group which may be substituted with a carboxyl group or a sulfo group, R ⁵ and R ⁶ Hydrogen; sulfo group; acetylamino group; hydroxy group or (C1-C4) alkyl group optionally substituted with (C1-C4) alkoxy group; hydroxy group, (C1-C4) alkoxy group, sulfo group or carboxyl group The ink composition according to (1), which is an optionally substituted (C1-C4) alkoxy group;
(3) An azo compound or a salt thereof, wherein the compound of the formula (1) is represented by the following formula (1a)

(In the formula (1a), R ^{1 to} R ³ are a sulfo group, a carboxyl group, a methyl group or a methoxy group, R ⁵ and R ⁶ are (C1 to C4) alkyl groups; a hydroxy group or a sulfo group may be substituted. (C1-C4) alkoxy group, the substitution position of B is 2 'or 3' position)
The ink composition according to (1),
(4) The ink composition according to any one of (1) to (3), wherein the salt is a lithium salt, a sodium salt, a potassium salt, an ammonium salt, or an ammonium salt represented by the general formula (2).

(In formula (2), Z ¹ , Z ² , Z ³ and Z ⁴ each independently represent a hydrogen atom, an alkyl group, a hydroxyalkyl group or a hydroxyalkoxyalkyl group.)
(5) An inkjet printer loaded with the ink composition according to any one of (1) to (4),
(6) A colored body colored by the ink jet printer according to (5),
(7) An azo compound represented by the formula (1b) or a salt thereof,

(In the formula (1b), R ¹ to R ³ are hydrogen; halogen atom; cyano group; hydroxy group; amino group; carboxyl group; sulfo group; sulfamoyl group optionally substituted with alkyl group or phenyl group; Nitro group; acyl group; phenyl group; ureido group; hydroxy group or (C1-C4) alkyl group optionally substituted with (C1-C4) alkoxy group; hydroxy group, (C1-C4) alkoxy group, sulfo group Or a (C1-C4) alkoxy group which may be substituted with a carboxyl group; an amino group substituted with a phenyl group which may be further substituted with a carboxyl group or a sulfo group; substituted with an alkyl group or an acyl group an amino group, R ⁴ is hydrogen; hydroxy group, (C1 -C4) alkoxy group, sulfo Motowaka Ku which may be substituted with a carboxyl group (C1 -C4) alkyl group; an amino group, an alkyl group, an alkoxy group, a phenyl group which may be substituted with a carboxyl group or a sulfo group, R ⁵ and R ⁶ Hydrogen; sulfo group; acetylamino group; hydroxy group or (C1-C4) alkyl group optionally substituted with (C1-C4) alkoxy group; hydroxy group, (C1-C4) alkoxy group, sulfo group or carboxyl group An optionally substituted (C1-C4) alkoxy group, wherein the bond A is substituted at the 2 or 3 position, B is substituted at the 2 'or 3' position, l is 1 or 2, and m and n are 0 or 1. The substitution position of (SO ₃ H) m is the 3 or 4 position, and the substitution position of (SO ₃ H) n is the 3 ′ or 4 ′ position.
About.

Since the azo compound of the present invention is excellent in water solubility, it has good filterability with a membrane filter in the production process of the ink composition, and is excellent in stability during storage and ejection stability of the recording liquid. Further, the ink composition of the present invention containing this azo compound has good storage stability without crystal precipitation, physical property change, color change and the like after long-term storage. Further, the recording black ink liquid containing the azo compound of the present invention is used for ink jet recording and writing instruments, and has a high print density of recorded images when recorded on plain paper and ink jet dedicated paper, and is further resistant to ozone gas. Excellent in light resistance, light resistance, moisture resistance and color rendering. By using it together with magenta, cyan and yellow dyes, full-color ink jet recording excellent in light resistance and water resistance is possible. Thus, the ink composition of the present invention is extremely useful as a black ink for inkjet recording.

Hereinafter, the present invention will be described in detail.
In R ¹ to R ³ in the general formula (1), examples of the sulfamoyl group which may be substituted with an alkyl group or a phenyl group include sulfamoyl, N-methylsulfamoyl, N-methylsulfamoyl, N- ( n-butyl) sulfamoyl, N, N-dimethylsulfamoyl, N, N-di (n-propyl) sulfamoyl, N-phenylsulfamoyl and the like.
Examples of the (C1-C4) alkyl group which may be substituted with a hydroxy group or a (C1-C4) alkoxy group in R ¹ to R ³ , R ⁵ and R ⁶ in the general formula (1) include methyl, ethyl , N-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, methoxyethyl, 2-ethoxyethyl, n-propoxyethyl, Examples include isopropoxyethyl, n-butoxyethyl, methoxypropyl, ethoxypropyl, n-propoxypropyl, isopropoxybutyl, n-propoxybutyl and the like.
Examples of (C1-C4) alkoxy group which may be substituted with a hydroxy group, a (C1-C4) alkoxy group, a sulfo group or a carboxyl group in R ¹ to R ³ , R ⁵ and R ⁶ in the general formula (1) As methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy, 2-hydroxyethoxy, 2-hydroxypropoxy, 3-hydroxypropoxy, methoxyethoxy, ethoxyethoxy, n-propoxy Ethoxy, isopropoxyethoxy, n-butoxyethoxy, methoxypropoxy, ethoxypropoxy, n-propoxypropoxy, isopropoxybutoxy, n-propoxybutoxy, 2-hydroxyethoxyethoxy, carboxymethoxy, 2-carboxyethoxy, 3-carboxy Bokishipuropokishi, 3-sulfopropoxy, 4-sulfobutoxy and the like.
In R ⁴ in the general formula (1), examples of the (C1 to C4) alkyl group which may be substituted with a hydroxy group, a (C1 to C4) alkoxy group, a sulfo group or a carboxyl group include methyl, ethyl, n- Propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, methoxyethyl, 2-ethoxyethyl, n-propoxyethyl, isopropoxyethyl N-butoxyethyl, methoxypropyl, ethoxypropyl, n-propoxypropyl, isopropoxybutyl, n-propoxybutyl, 2-hydroxyethoxyethyl, carboxymethyl, 2-carboxyethyl, 3-carboxypropyl, 2-sulfoethyl, 3 -Sulfopro Le, 4-sulfobutyl and the like. Examples of the phenyl group which may be substituted with an amino group, an alkyl group, an alkoxy group, a carboxyl group or a sulfo group include phenyl, methylphenyl, methoxyphenyl, aminophenyl, sulfophenyl, aminosulfophenyl, methylsulfophenyl, Examples include methoxysulfophenyl, bissulfophenyl, carboxyphenyl, biscarboxyphenyl, and the like.
Examples of the amino group substituted with a phenyl group which may be further substituted with a carboxyl group or a sulfo group in R ¹ to R ³ in the general formula (1) include phenylamino, sulfophenylamino, bissulfophenyl Amino, carboxyphenylamino, biscarboxyphenylamino and the like can be mentioned. Examples of amino groups substituted by alkyl groups or acyl groups include methylamino, ethylamino, n-propylamino, isopropylamino, n-butylamino, isobutylamino, N, N-dimethylamino, N, N- Examples include diethylamino, N, N-di (n-propyl) amino, N, N-di (isopropyl) amino, ethylmethylamino, acetylamino, propionylamino, butyrylamino, benzoylamino and the like.

Preferred R ¹ to R ³ in the general formula (1) are hydrogen, methyl, methoxy, ethyl, ethoxy, propyl, propoxy, 2-hydroxyethoxy, 2-methoxyethoxy, 2-ethoxyethoxy, 3-sulfopropoxy, 4- Sulfobutoxy, carboxymethoxy, 2-carboxyethoxy, chlorine, bromine, cyano, nitro, acetyl, benzoyl, carboxyl, sulfonic acid, sulfamoyl, N-ethylsulfamoyl, phosphoric acid, hydroxy, amino, carboxymethylamino, carboxypropyl Amino, bis-carboxymethylamino, acetylamino, benzoylamino, ureido, phenylamino, sulfophenylamino, carboxyphenylamino, dicarboxyphenylamino, etc., more preferably hydrogen, methyl, methato Xyl, ethoxy, 2-hydroxyethoxy, 3-sulfopropoxy, nitro, carboxyl, sulfonic acid, phosphoric acid, acetylamino.
Particularly preferred combinations of R ¹ to R ³ include 2-aminobenzenesulfonic acid (ortanylic acid), 3-aminobenzenesulfonic acid (methanilic acid), and 4-aminobenzenesulfonic acid as shown by the following formula (6). (Sulfanilic acid), 2-aminobenzene-1,4-disulfonic acid (AS acid), 2-aminobenzoic acid (anthranilic acid), 3-aminobenzoic acid, 4-aminobenzoic acid, 2-aminobenzene-1, 4-dicarboxylic acid, 4-aminobenzene-1,2-dicarboxylic acid, 5-aminobenzene-1,3-dicarboxylic acid, 2-amino-4-sulfobenzoic acid, 2-amino-5-sulfobenzoic acid, 2 -Amino-5-methylbenzenesulfonic acid, 5-amino-2-methylbenzenesulfonic acid, 4-amino-3-methylbenzenesulfonic acid, 4-amino- 5-methylbenzene-1,3-disulfonic acid, 2-amino-5-methoxybenzenesulfonic acid, 4-amino-3-methoxybenzenesulfonic acid, and 2-amino-4-methoxybenzenesulfonic acid.
Preferred R ⁴ in the general formula (1) is hydrogen, methyl, ethyl, propyl, 2-hydroxyethyl, 2-methoxyethyl, 2-sulfoethyl, 3-sulfopropyl, 4-sulfobutyl, carboxymethyl, phenyl, aminosulfophenyl. , Methoxysulfophenyl, and carboxyphenyl, more preferably hydrogen, methyl, 2-hydroxyethyl, 3-sulfopropyl, and phenyl, and particularly preferably phenyl.
Preferred R ⁵ and R ⁶ in the general formula (1) are hydrogen, methyl, methoxy, ethyl, ethoxy, propyl, propoxy, 2-hydroxyethoxy, 2-methoxyethoxy, 3-sulfopropoxy, 4-sulfobutoxy, carboxymethoxy 2-carboxyethoxy, sulfonic acid, acetylamino and the like, more preferably methyl, methoxy, ethoxy, 2-hydroxyethoxy and 3-sulfopropoxy. As a particularly preferred combination of R ⁵ and R ⁶ , R ⁵ is 3-sulfopropoxy, R ⁶ is methyl, or both R ⁵ and R ⁶ are 2-hydroxyethoxy.

The salt of the compound represented by the formula (1) is an inorganic or organic cation salt. Of 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, and organic cation salts. Examples of the salt include, but are not limited to, salts of the compound represented by the formula (2).

Examples of alkyl groups of Z ¹ , Z ² , Z ³ and Z ^{4 in} the general formula (2) include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl and the like. 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 and the like hydroxy- (C1-C4) alkyl groups are mentioned, and examples of hydroxyalkoxyalkyl groups include hydroxyethoxymethyl group, 2-hydroxyethoxyethyl group, 3-hydroxyethoxypropyl group, 2-hydroxyethoxypropyl group, 4-hydroxyethoxy. Butyl group, 3-hydroxyethoxybutyl group, 2 Hydroxyethoxy butyl group such as hydroxyethyl (C1 -C4) alkoxy - (C1 -C4) alkyl group. Among these hydroxyethoxy - (C1 -C4) alkyl groups are preferred. 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, Examples include hydroxyethoxy- (C1-C4) alkyl groups such as 2-hydroxyethoxybutyl group.

Specific examples of Z ¹ , Z ² , Z ³ and Z ^{4 in} the general formula (2) are shown in (Table 1).

(Table 1)
Compound No. Z ¹ Z ² Z ³ Z ⁴
1-1 H -C2H4OH -C2H4OH -C2H4OH
1-2 CH3 -C2H4OH -C2H4OH -C2H4OH
1-3 H -CH2CH (OH) CH3 -CH2CH (OH) CH3 -CH2CH (OH) CH3
1-4 CH3 -CH2CH (OH) CH3 -CH2CH (OH) CH3 -CH2CH (OH) CH3
1-5 H -C2H4OH H -C2H4OH
1-6 CH3 -C2H4OH H -C2H4OH
1-7 H -CH2CH (OH) CH3 H -CH2CH (OH) CH3
1-8 CH3 -CH2CH (OH) CH3 H -CH2CH (OH) CH3
1-9 CH3 -C2H4OH CH3 -C2H4OH
1-10 CH3 -CH2CH (OH) CH3 CH3 -CH2CH (OH) CH3

  The azo compound of the present invention represented by the general formula (1) can be synthesized, for example, by the following method. Here, the description about the substitution position of each substituent is omitted, and the structural formula of the compound in each step is expressed in the form of a free acid. That is, the general formula (3)

(Wherein n has the same meaning as n in formula (1)), and the compound (4) is diazotized by a conventional method.

(Wherein R ⁴ has the same meaning as R ⁴ in the general formula (1).) And the coupling reaction, the resulting formula (5)

(Wherein n and R ⁴ have the same meaning as described above), the compound represented by the general formula (6)

(Wherein R ¹ , R ² and R ³ have the same meaning as R ¹ , R ² and R ³ in the general formula (1)) 7)

(Wherein m has the same meaning as m in general formula (1).) General formula (8) obtained by coupling reaction with the compound represented by

(Wherein R ¹ , R ² , R ³ and m have the same meaning as described above) are coupled with a compound diazotized by a conventional method to give a compound of the general formula (9)

(Wherein R ¹ , R ² , R ³ , R ⁴ , m and n have the same meaning as described above) are obtained. This is hydrolyzed general formula (10)

(Wherein R ¹ , R ² , R ³ , R ⁴ , m and n have the same meaning as described above), the compound represented by the general formula (11)

(Wherein l has the same meaning as l in general formula (1)), a compound obtained by diazotizing a compound represented by general formula (12)

(Wherein R ⁵ and R ⁶ have the same meanings as R ⁵ and R ⁶ in general formula (1)). General formula (13) obtained by coupling to a compound represented by

(Wherein R ⁵ , R ⁶ and l have the same meaning as described above) General formula (14) obtained by coupling reaction of a compound diazotized by a conventional method

By hydrolyzing the compound (wherein R ¹ to R ⁶ , l, m and n have the same meaning as described above), the general formula (1) which is the azo compound of the present invention can be obtained.
Further, a compound obtained by diazotizing a compound of the general formula (13) by a conventional method is represented by the general formula (15)

(Wherein n has the same meaning as described above) General Formula (16) obtained by coupling to the compound represented by

(Wherein R ⁵ , R ⁶ , l and n have the same meaning as described above).

(Wherein R ⁵ , R ⁶ , l and n have the same meaning as described above), a compound diazotized by a conventional method is coupled to a compound represented by the general formula (7), General formula (18) obtained

(Wherein R ⁴ , R ⁵ , R ⁶ , l and n have the same meaning as described above), a compound obtained by diazotizing a compound represented by the general formula (8) by a conventional method. The general formula (1) which is the azo compound of the present invention can also be obtained by ringing.

Although it does not specifically limit as a suitable example of the compound shown in General formula (1), The following structure is mentioned concretely. In the table, the sulfonic acid group is represented in the form of a free acid.

 The diazotization of the compound of general formula (3) 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 30 ° C, preferably 5 to 15 ° C. It is carried out using alkali metal nitrite. Coupling of the diazotized compound of the compound of general formula (3) and the compound of general formula (4) is also carried out under conditions known per se. It is advantageous to carry out in an aqueous or aqueous organic medium, for example at a temperature of -5 to 30 ° C, preferably 5 to 20 ° C and an acidic to neutral pH value. Preferably, it is carried out at a weakly acidic to neutral pH value, for example, pH 2-6. The pH value is adjusted by adding a base. Examples of the base that can be used include alkali metal hydroxides such as lithium hydroxide and sodium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate, acetates such as sodium acetate, ammonia and organic amines. . The compounds of general formulas (3) and (4) are used in approximately stoichiometric amounts.

The diazotization of the compound of general formula (6) is also carried out in a manner known per se, for example nitrites such as sodium nitrite in inorganic acid media, for example at temperatures of -5 to 30 ° C., preferably 0 to 15 ° C. It is carried out using an alkali metal nitrite salt. Coupling of the diazotized compound of the compound of general formula (6) and the compound of general formula (7) is also carried out under conditions known per se. It is advantageous to carry out the reaction in an aqueous or aqueous organic medium, for example at a temperature of -5 to 30 ° C, preferably 10 to 25 ° C and a weakly acidic to alkaline pH value. It is preferably carried out at a weakly acidic to weakly alkaline pH value, for example, pH 5 to 10, and the pH value is adjusted by adding a base. Examples of bases that can be used include alkali metal hydroxides such as lithium hydroxide and sodium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate, acetates such as sodium acetate, and ammonia or organic amines. it can. The compounds of general formulas (6) and (7) are used in approximately stoichiometric amounts.

The diazotization of the compound of the general formula (8) is also carried out in a manner known per se, for example nitrites such as sodium nitrite at a temperature of eg -5 to 30 ° C., preferably 5 to 20 ° C. in an inorganic acid medium. It is carried out using an alkali metal nitrite salt. Coupling of the diazotized compound of the compound of the general formula (8) and the compound of the general formula (5) is also carried out under conditions known per se. It is advantageous to carry out the reaction in an aqueous or aqueous organic medium, for example at a temperature of -5 to 30 ° C, preferably 10 to 25 ° C and a weakly acidic to alkaline pH value. It is preferably carried out at a weakly acidic to weakly alkaline pH value, for example, pH 5 to 10, and the pH value is adjusted by adding a base. Examples of bases that can be used include alkali metal hydroxides such as lithium hydroxide and sodium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate, acetates such as sodium acetate, and ammonia or organic amines. it can. The compounds of general formulas (8) and (5) are used in approximately stoichiometric amounts.

Production of the compound of general formula (10) by hydrolysis of the compound of general formula (9) is also carried out by a method known per se. The method is preferably a method of heating in an aqueous alkaline medium. For example, after adding sodium hydroxide or potassium hydroxide to a reaction solution containing the compound of the general formula (9) to adjust the pH to 9.5 or higher, for example, 20 to It is carried out by heating to a temperature of 150 ° C., preferably 30 to 100 ° C. At this time, the pH value of the reaction solution is preferably maintained at 9.5 to 11.5. The pH value is adjusted by adding a base. As the base, those described above can be used.

The diazotization of the compound of general formula (11) is also carried out in a manner known per se, for example a nitrite such as sodium nitrite in an inorganic acid medium, for example at a temperature of -5 to 30 ° C, preferably 0 to 15 ° C. It is carried out using an alkali metal nitrite salt. Coupling of the diazotized compound of the compound of the general formula (11) and the compound of the general formula (12) is also carried out under conditions known per se. It is advantageous to carry out in an aqueous or aqueous organic medium, for example at a temperature of -5 to 30 ° C, preferably 5 to 20 ° C and an acidic to weakly alkaline pH value. It is preferably carried out at an acidic to neutral pH value, for example, pH 2 to 6, and the pH value is adjusted by adding a base. Examples of bases that can be used include alkali metal hydroxides such as lithium hydroxide and sodium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate, acetates such as sodium acetate, and ammonia or organic amines. it can. The compounds of general formulas (11) and (12) are used in approximately stoichiometric amounts.

The diazotization of the compound of the general formula (13) is also carried out in a manner known per se, for example nitrites such as sodium nitrite in inorganic acid media, for example at temperatures of -5 to 30 ° C., preferably 5 to 20 ° C. It is carried out using an alkali metal nitrite salt. The coupling of the diazotized compound of the compound of the general formula (13) and the compound of the general formula (10) is also carried out under conditions known per se. It is advantageous to carry out the reaction in an aqueous or aqueous organic medium, for example at a temperature of -5 to 30 ° C, preferably 10 to 25 ° C and a weakly acidic to alkaline pH value. It is preferably carried out at a weakly acidic to weakly alkaline pH value, for example, pH 5 to 10, and the pH value is adjusted by adding a base. Examples of bases that can be used include alkali metal hydroxides such as lithium hydroxide and sodium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate, acetates such as sodium acetate, and ammonia or organic amines. it can. The compounds of general formulas (13) and (10) are used in approximately stoichiometric amounts.

Production of the compound of general formula (1) by hydrolysis of the compound of general formula (14) is also carried out by a method known per se. The method is preferably a method of heating in an aqueous alkaline medium. For example, after adding sodium hydroxide or potassium hydroxide to a reaction solution containing the compound of the general formula (14) to adjust the pH to 9.5 or higher, for example, 20 to It is carried out by heating to a temperature of 150 ° C., preferably 30 to 100 ° C. At this time, the pH value of the reaction solution is preferably maintained at 9.5 to 11.5. The pH value is adjusted by adding a base. As the base, those described above can be used.

The azo compound represented by the general formula (1) or a salt thereof according to the present invention (hereinafter, unless otherwise specified, the compound or a salt thereof is simply referred to as a compound) is added in the form of a free acid by adding a mineral acid after the coupling reaction. It can be isolated and the inorganic salts can be removed from it by washing with water or acidified water. Next, the acid type dye having a low salt content thus obtained can be neutralized with a desired inorganic or organic base in an aqueous medium to obtain a solution of the corresponding salt. Examples of inorganic bases include, for example, alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide, ammonium hydroxide, or alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate. Examples of the organic base include, but are not limited to, organic amines such as alkanolamines such as diethanolamine and triethanolamine.

Hereinafter, the ink composition and the inkjet ink of the present invention will be described. The aqueous composition containing the azo compound represented by the general formula (1) of the present invention can dye materials made of cellulose. In addition, other materials having a carbonamide bond can be dyed, and can be widely used for dyeing leather, fabrics and paper. On the other hand, a preferred method of using the compound of the present invention is an ink composition dissolved in a liquid medium.

The reaction liquid containing the azo compound of the present invention represented by the general formula (1) can be directly used for production of a recording ink composition. However, it is first isolated by drying, eg spray drying, or salted out with inorganic salts such as sodium chloride, potassium chloride, calcium chloride, sodium sulfate or acidified with mineral acids such as hydrochloric acid, sulfuric acid, nitric acid. Alternatively, the azo compound of the present invention can be taken out by acid salting out by combining salting out and aciding out, and then processed into an ink composition.

The ink composition of the present invention usually contains 0.1 to 20% by mass, preferably 1 to 10% by mass, more preferably 2 to 8% by mass of the azo compound of the present invention represented by the general formula (1). It is a composition which uses as a main medium. The ink composition of the present invention may further contain, for example, 0 to 30% by mass of a water-soluble organic solvent and 0 to 5% by mass of an ink preparation agent, for example. The pH of the ink composition is preferably pH 6 to 11 and more preferably pH 7 to 10 in terms of improving storage stability. Moreover, as surface tension of a coloring composition, 25-70 mN / m is preferable and 25-60 mN / m is more preferable. Furthermore, the viscosity of the colored composition is preferably 30 mPa · s or less, and more preferably 20 mPa · s or less.
In the aqueous ink composition of the present invention, the azo compound represented by the general formula (1) is dissolved in water or a water-soluble organic solvent (an organic solvent or water containing an organic solvent miscible with water). A preparation is added. When this water-based ink composition is used as an ink for an ink jet printer, it is preferable to use an azo compound having a low content of inorganic substances such as metal cation chlorides and sulfates. For example, it is about 1% by mass or less (to the chromogen). In order to produce an azo compound with a small amount of inorganic substances, for example, a conventional method using a reverse osmosis membrane or a dried product or wet cake of the azo compound of the present invention is stirred in a mixed solvent of alcohol such as methanol and water, filtered and dried. What is necessary is just to desalinate by the method of these.

Examples of water-soluble organic solvents that can be used in the preparation of the ink composition include C1-C4 alkanols such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, and tert-butanol, and N, N-dimethylformamide. Or carboxylic acid amides such as N, N-dimethylacetamide, lactams such as 2-pyrrolidone and N-methylpyrrolidin-2-one, 1,3-dimethylimidazolidin-2-one or 1,3-dimethylhexahydropyrimido Cyclic ureas such as 2-one, ketones such as acetone, methyl ethyl ketone, 2-methyl-2-hydroxypentan-4-one or cyclic ethers such as keto alcohol, tetrahydrofuran, dioxane, ethylene glycol, 1,2-propylene Glycol, , 3-propylene glycol, 1,2-butylene glycol, 1,4-butylene glycol, 1,6-hexylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, thiodi Monomers having (C2 to C6) alkylene units such as glycol, dithiodiglycol, oligomers or polyalkylene glycols or thioglycols, polyols (triols) such as glycerin, hexane-1,2,6-triol, ethylene glycol monomethyl ether or Ethylene glycol monoethyl ether, diethylene glycol monomethyl ether or diethylene glycol monoethyl ether or triethylene glycol Polyhydric alcohol (C1 -C4) alkyl ethers such as monomethyl ether or triethylene glycol monoethyl ether, gamma-butyrolactone or dimethyl sulfoxide and the like. These organic solvents may be used alone or in combination of two or more.

Examples of the ink preparation used in the preparation of the ink composition include antiseptic / antifungal agents, pH adjusters, chelating reagents, rust inhibitors, water-soluble ultraviolet absorbers, water-soluble polymer compounds, dye solubilizers, and antioxidants. Agents, surfactants and the like.
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 coloring 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, benzothiazole, nitrile, pyridine, and 8-oxyquinoline. , Benzothiazole, isothiazoline, dithiol, pyridine oxyd, nitropropane, organotin, phenol, quaternary ammonium salt, triazine, thiazine, anilide, adamantane, dithiocarbamate, brominated indanone And compounds such as benzyl bromacetate and inorganic salts. Examples of the organic halogen compound include sodium pentachlorophenol, examples of the pyridine oxido compound include sodium 2-pyridinethiol-1-oxide, and examples of the inorganic salt compound include anhydrous sodium acetate. Examples of the isothiazoline-based compound include 1,2-benzisothiazolin-3-one, 2-n-octyl-4-isothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, and 5 -Chloro-2-methyl-4-isothiazolin-3-one magnesium chloride, 5-chloro-2-methyl-4-isothiazolin-3-one calcium chloride, 2-methyl-4-isothiazolin-3-one calcium chloride, etc. Can be mentioned. Other antiseptic / antifungal agents include 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, for example, 5 to 11 without adversely affecting the prepared ink. Examples include alkanolamines such as diethanolamine, triethanolamine, N-methyldiethanolamine, alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, ammonium hydroxide (ammonia), or lithium carbonate. And alkali metal carbonates such as sodium carbonate, sodium hydrogen carbonate and potassium carbonate, and inorganic bases such as potassium acetate, sodium silicate and disodium phosphate.
Examples of the chelating reagent include sodium 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 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 solubilizer 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, heterocycles, and the like.
Examples of the surfactant include known surfactants such as anionic, cationic, and nonionic surfactants. Examples of the anionic surfactant include alkyl sulfonic acid, alkyl carboxylate, α-olefin sulfonate, polyoxyethylene alkyl ether acetate, N-acyl amino acid and its salt, N-acyl methyl taurate, alkyl sulfate polyoxy Alkyl 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, alkylallylsulfone hydrochloride, diethylsulfone Acid salts, dioctyl sulfosuccinate diethyl hexylsilsulfosuccinate and the like. Examples of the cationic surfactant include 2-vinylpyridine derivatives and poly-4-vinylpyridine derivatives. Amphoteric surfactants include lauryldimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, coconut oil fatty acid amidopropyldimethylaminoacetic acid betaine, polyoctylpolyaminoethylglycine and other imidazoline derivatives. is there. Nonionic surfactants include polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene alkyl ether, polyoxyallylalkyl. Ethers such as alkyl ethers, polyoxyethylene oleic acid, polyoxyethylene oleate, polyoxyethylene distearate, sorbitan laurate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, polyoxyethylene monooleate Esters, polyoxyethylene stearate, 2,4,7,9-tetramethyl-5-decyne-4,7-di Acetylene glycols such as 3,6-dimethyl-4-octyne-3,6-diol, 3,5-dimethyl-1-hexyne-3ol (for example, Surfinol 104105, 82 manufactured by Nisshin Chemical Co., Ltd.) 465, Olfin STG, etc.). These ink preparation agents are used alone or in combination.

The aqueous ink composition of the present invention can be obtained by mixing and stirring the above components in an arbitrary order. The obtained ink composition may be filtered with a membrane filter or the like in order to remove impurities. Further, in order to finely adjust the black color, other pigments having various hues may be mixed. In that case, in addition to the azo compound represented by the general formula (1) of the present invention, black, yellow, magenta, cyan, and other color pigments having other hues can be used.

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 used as an ink-jet ink containing the ink composition. It is particularly preferred. Therefore, the inkjet ink of the present invention is characterized by containing the ink composition of the present invention, and the inkjet ink of the present invention is suitably used in the inkjet recording method of the present invention described later.

Next, the ink jet recording method of the present invention will be described. The ink jet recording method of the present invention is characterized in that recording is performed using an ink jet ink containing the ink composition. In the ink jet recording method of the present invention, recording is performed on an image receiving material using an ink jet ink containing the ink composition, but there are no particular restrictions on the ink nozzles used at that time, depending on the purpose. Can be selected as appropriate.

The image receiving material is not particularly limited, and examples thereof include known recording materials such as plain paper, resin-coated paper, ink jet exclusive paper, film, electrophotographic co-paper, fabric, glass, metal, and ceramics.

In the ink jet recording method of the present invention, among the image receiving materials, the following recording papers and recording films called, for example, ink jet exclusive paper, ink jet exclusive glossy paper, and ink jet exclusive film are particularly preferable.

The recording paper and the recording film are formed by laminating a support and an image receiving layer and, if necessary, laminating other layers such as a back coat layer. Each layer including the image receiving layer may be one layer or two or more layers.

The support is composed of chemical pulp such as LBKP and NBKP, mechanical pulp such as GP, PGW, RMP, TMP, CTMP, CMP, and CGP, and waste paper pulp such as DIP. , Binders, sizing agents, fixing agents, cationic agents, paper strength enhancers, etc., which are added and mixed, and manufactured with various devices such as long net paper machines and circular net paper machines can be used. In addition, synthetic paper, plastic film sheets, and the like may be used.

The thickness of the support is about 10 to 250 μm, and the basis weight is preferably 10 to 250 g / m ² .

The support may be provided with the image receiving layer, may further be provided with the back coat layer, and after providing a size press or anchor coat layer with starch, polyvinyl alcohol or the like, the image receiving layer and The back coat layer may be provided. The support may be flattened by a calendar device such as a machine calendar, a TG calendar, or a soft calendar.

Among the above-mentioned supports, papers laminated on both sides with polyolefin (for example, polyethylene, polystyrene, polyethylene terephthalate, polybutene, and copolymers thereof) and plastic films are preferably used.

The image receiving layer contains a pigment, an aqueous binder, a mordant, a water resistance agent, a light resistance improver, a surfactant, and other additives.

The pigment is preferably a white pigment, and examples of the white pigment include calcium carbonate, kaolin, talc, clay, diatomaceous earth, synthetic amorphous silica, aluminum silicate, magnesium silicate, calcium silicate, aluminum hydroxide, alumina, Preferable examples include inorganic white pigments such as lithopone, zeolite, barium sulfate, calcium sulfate, titanium dioxide, zinc sulfide and zinc carbonate, and organic pigments such as styrene pigment, acrylic pigment, urea resin and melamine resin. Among these white pigments, porous inorganic pigments are preferable.

Examples of the aqueous binder include water-soluble polymers such as polyvinyl alcohol, silanol-modified polyvinyl alcohol, starch, cationized starch, casein, gelatin, carboxymethylcellulose, hydroxyethylcellulose, polyvinylpyrrolidone, polyalkylene oxide, and polyalkylene oxide derivatives. And water dispersible polymers such as styrene butadiene latex and acrylic emulsion. These aqueous binders may be used alone or in combination of two or more.

A polymer mordant is preferably used as the mordant.

The water-proofing agent is effective for making the image water-resistant, and a cationic resin is preferable. Examples of the cationic resin include polyamide polyamine epichlorohydrin, polyethyleneimine, polyamine sulfone, dimethyldiallylammonium chloride polymer, cationic polyacrylamide, colloidal silica, and the like.

Examples of the light resistance improver include zinc sulfate, zinc oxide, hindered amine-based antioxidants, benzophenone-based and benzotriazole-based ultraviolet absorbers, and the like.

The surfactant functions as a coating aid, a peelability improver, a slippage improver or an antistatic agent. An organic fluoro compound may be used in place of the surfactant. Examples of the organic fluoro compound include a fluorine surfactant, an oily fluorine compound (for example, fluorine oil) and a solid fluorine compound resin (for example, tetrafluoroethylene resin).

Examples of the other additives include pigment dispersants, thickeners, antifoaming agents, dyes, fluorescent whitening agents, preservatives, pH adjusting agents, matting agents, and hardening agents.

The back coat layer contains a white pigment, an aqueous binder, and other components.

Examples of the white pigment include light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate. , Magnesium silicate, synthetic amorphous silica, colloidal silica, colloidal alumina, pseudoboehmite, aluminum hydroxide, alumina, lithopone, zeolite, hydrous halloysite, magnesium carbonate, magnesium hydroxide, white inorganic pigments, styrene plastic pigment, acrylic Organic pigments such as plastic pigments, polyethylene, microcapsules, urea resins, melamine resins, and the like.

Examples of the aqueous binder include styrene / maleate copolymer, styrene / acrylate copolymer, polyvinyl alcohol, silanol-modified polyvinyl alcohol, starch, cationized starch, casein, gelatin, carboxymethylcellulose, hydroxyethylcellulose, and polyvinylpyrrolidone. And water-dispersible polymers such as styrene butadiene latex and acrylic emulsion.

Examples of the other components include an antifoaming agent, an antifoaming agent, a dye, a fluorescent brightening agent, a preservative, and a water-proofing agent.

A polymer latex may be added to the constituent layers (including the backcoat layer) in the recording paper and recording film. The polymer latex is used for the purpose of improving film physical properties such as dimensional stabilization, curling prevention, adhesion prevention, and film cracking prevention. When a polymer latex having a low glass transition temperature (40 ° C. or lower) is added to the layer containing the mordant, cracking and curling of the layer can be prevented. Further, curling can be prevented by adding a polymer latex having a high glass transition temperature to the back coat layer.

The ink jet recording system of the present invention is not particularly limited, and is a known method, for example, a charge control system that ejects ink using electrostatic attraction, a drop-on-demand system (pressure) that uses the vibration pressure of a piezo element. Pulse system), acoustic ink jet system that changes electrical signal into acoustic beam, irradiates ink and uses ink to discharge ink, thermal ink jet that heats ink to form bubbles and uses generated pressure (bubble) Any of a jet (registered trademark) system may be used. The inkjet recording method includes a method of ejecting a large number of low-density inks called photo inks in a small volume, a method of improving image quality using a plurality of inks having substantially the same hue and different concentrations, and colorless and transparent. A method using ink is included.

The azo compound of the present invention is excellent in water solubility, and the ink composition of the present invention containing this azo compound has good storage stability without crystal precipitation, physical property change, color change, etc. after long-term storage. The black ink liquid for recording containing the azo compound of the present invention is used for ink jet recording and writing instruments. When recorded on plain paper and ink jet exclusive paper, the hue of the recorded image is neutral and the print density is high. It is high black and has excellent ozone gas resistance, light resistance, moisture resistance and color rendering.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited at all by the following example. In the following examples, “part” means “part by mass” and “%” means “% by mass”.

Example 1
(1) 28.4 parts of the compound of the formula (19) are dissolved in 300 parts of water while adjusting the pH to 6.0 to 8.0 with sodium carbonate, and after addition of 18.7 parts of 35% hydrochloric acid, 0 to 5 Then, 10.7 parts of 40% aqueous sodium nitrite solution was added to diazotize.

  After adding a solution obtained by suspending 18.1 parts of 6-phenylamino-1-hydroxynaphthalene-3-sulfonic acid in 200 parts of water to this diazo suspension, the pH value of the solution was adjusted at 10 to 20 ° C. It stirred for 12 hours, hold | maintaining to 2.0-2.7 with sodium carbonate. After stirring, the pH value was dissolved with sodium carbonate to 7.0 to 8.5 to obtain an aqueous solution containing the monoazo compound of the formula (20).

(2) 10.4 parts of 2-aminobenzenesulfonic acid are dissolved in 50 parts of water while adjusting the pH to 3.5 to 5.5 with sodium hydroxide, and 17.0 parts of 35% hydrochloric acid at 0 to 10 ° C. Then, 10.5 parts of 40% aqueous sodium nitrite solution was added for diazotization. Next, 14.3 parts of 6-amino-1-hydroxynaphthalene-3-sulfonic acid is dissolved in 70 parts of water while adjusting the pH to 6.5 to 7.5 with sodium hydroxide, and anhydrous at 25 to 35 ° C. Acetylated by addition of 6.2 parts of acetic acid. The diazo suspension was added dropwise thereto while maintaining the pH value of the solution at 6.5 to 7.5 with sodium carbonate. After completion of the dropwise addition, the mixture was stirred at 15 to 30 ° C. for 2 hours at pH 7.0 to 8.0 to complete the coupling reaction, thereby obtaining a reaction solution containing the compound of the formula (21).

The reaction solution containing the compound of the formula (21) obtained above was heated to 90 ° C. After heating, sodium hydroxide was added to 2% by weight and maintained at 90-95 ° C. for about 1 hour. After cooling to room temperature, the pH was adjusted to 3.5 to 5.0 with 35% hydrochloric acid, sodium chloride was added for salting out, filtered, and dried to obtain 23.0 parts of the compound of formula (22).

(3) In 200 parts of water, 23.0 parts of the compound of the formula (22) obtained in the above reaction was dissolved while adjusting the pH to 6.0 to 7.5 with sodium hydroxide, and the solution was added at 15 to 25 ° C. After adding 19.9 parts of 35% hydrochloric acid, 9.9 parts of 40% aqueous sodium nitrite solution was added to diazotize. The obtained diazo suspension was kept in an aqueous solution containing the compound of the formula (20) obtained by the reaction (1) above, and the pH value of the aqueous solution was maintained at 7.5 to 8.5 with sodium carbonate. However, it was dripped at 15-25 degreeC over 30 minutes. After completion of the dropwise addition, the mixture was stirred at 15 to 30 ° C. for 3 hours at pH 8.0 to 9.0 to complete the coupling reaction, thereby obtaining a reaction solution containing the compound of the formula (23).

The reaction solution was heated to 75 ° C. and reacted for 1 hour while maintaining the pH at 10.8 to 11.0 with sodium hydroxide. After the reaction, the pH of the reaction solution was adjusted to 6.0 to 7.5 with 35% hydrochloric acid, sodium chloride was added to salt out, and filtration was performed to obtain 46.5 parts of the compound of the formula (24).

(4) To 100 parts of N, N-dimethylformamide, 51.0 parts of 2-nitro-4-cresol, 50.0 parts of toluene and 19.5 parts of potassium hydroxide were added, and the resulting solution was added at 120 to 125 ° C. And stirred for 1 hour to distill off water produced by azeotropy with toluene. After raising the liquid temperature to 130 to 135 ° C., 44.8 parts of propane sultone diluted with 50 parts of N, N-dimethylformamide was added dropwise over about 30 minutes. After reacting at the same temperature for 1 hour, the mixture was cooled to room temperature, 150 parts of water was added, and the pH was adjusted to 7.5 to 8.5 with a sodium hydroxide solution. This solution was concentrated by a rotary evaporator, transferred to an autoclave, and 1.0 part of 50% water-containing 5% palladium carbon was added. After enclosing hydrogen gas, the mixture was reacted at 55 to 65 ° C. for 2 hours to obtain a solution containing 56.8 parts of the compound of formula (25).

(5) After dissolving 74.3 parts of the compound of the formula (25) in 900 parts of water while adjusting the pH to 1.0 to 3.0 with hydrochloric acid, the temperature is adjusted to 5 to 10 ° C., and 53.2 parts of 35% hydrochloric acid, Diazotization was performed by adding 27.0 parts of 40% aqueous sodium nitrite solution.

Next, a solution containing 36.8 parts of the compound of the formula (21) obtained by the above reaction was slowly added dropwise to the diazo suspension of the compound of the formula (25) at a temperature of 0 to 10 ° C. After completion of the dropwise addition, the pH value is adjusted to 3.0 to 4.0 by addition of an aqueous sodium hydroxide solution, and then maintained at that pH for 1 hour at 5 to 10 ° C. and 2 hours at 15 to 25 ° C. After stirring at pH 3.0 to 4.0, an aqueous sodium hydroxide solution was added to complete the coupling reaction with a pH value of 7.0 to 8.0, and a reaction solution containing the compound of formula (27) was prepared. Obtained.

(6) Take 1/6 amount of the obtained reaction solution containing the compound of formula (27), add 16.5 parts of 35% hydrochloric acid thereto, add 8.7 parts of 40% aqueous sodium nitrite solution, and add diazo Turned into. The obtained diazo solution was adjusted to a solution obtained by dissolving 46.5 parts of the compound of formula (24) in 1000 parts of water, and the pH value of the solution was adjusted to 8.5 to 9.5 with sodium carbonate. While maintaining the pH, the solution was added dropwise at 15 to 30 ° C. over 30 minutes. After completion of the dropwise addition, the mixture was stirred for 3 hours while maintaining the temperature and the pH to complete the coupling reaction, thereby obtaining a reaction solution containing the compound of the formula (28).

(7) The reaction solution was heated to 75 ° C. and reacted for 1 hour while maintaining the pH at 10.8 to 11.0 with sodium hydroxide. After the reaction, the pH was adjusted to 6.0-7.5 with 35% hydrochloric acid, sodium chloride was added, salted out, and filtered. The total amount of the cake obtained was dissolved in 500 parts of water, crystallized by adding 500 parts of methanol, the crystals were desalted by filtration and separation, and then dried to dry the formula (29) (Compound No. 5) of the present invention. 14) 55.1 parts of compound 14) were obtained. The maximum absorption wavelength (λmax) of this compound in water was 570 nm, and the solubility in water was 100 g / l or more.

Example 2
The compound of formula (31) (compound No. 1) of the present invention was prepared in the same manner as in Example 1, except that 28.4 parts of the compound of formula (19) of Example 1 were changed to 23.6 parts of compound of the following formula (30). ) Was obtained. The maximum absorption wavelength of this compound in water was 578 nm, and the solubility in water was 100 g / l or more.

Examples 3-4
(A) Preparation of ink An ink composition was prepared by mixing the following components, and filtered through a 0.45 μm membrane filter to obtain an aqueous ink composition of the present invention for inkjet.

Table 5
5.0 parts of the compound obtained in the above-mentioned Example (Used after desalting)
Glycerin 5.0 parts Urea 5.0 parts N-methyl-2-pyrrolidone 4.0 parts Isopropyl alcohol 3.0 parts Butyl carbitol 2.0 parts Surfactant 0.1 parts (Surfinol 105 manufactured by Nisshin Chemical Co., Ltd.) )
Water + aqueous lithium hydroxide 75.9 parts Total 100.0 parts

In Table 5, the compound obtained in the above-mentioned example shows a compound of the formula (29) in Example 3, and a compound of the formula (31) in Example 4. The pH during ink preparation was adjusted to 8 to 10 with aqueous ammonia. This aqueous ink composition did not cause precipitation separation during storage, and did not change its physical properties even after long-term storage.

(B) Inkjet printing Using each of the ink compositions obtained above, plain paper (Canon TLB5A4) and special glossy paper A (Canon Professional Photo Paper PR) were obtained using an inkjet printer (trade name Canon BJ-S630). -101) and exclusive glossy paper B (EPSON company PM photo paper (glossy) KA420PSK) were subjected to ink jet recording.
At the time of printing, an image pattern was prepared so that gradations with several levels of reflection density were obtained, and a half-tone black print was obtained. Since the gray scale mode is used at the time of printing, yellow, cyan, and magenta recording liquids other than the black recording liquid are not used together in this light color portion. Among the test methods described below, in the hue density evaluation, which is an item to be evaluated using a colorimeter, when measuring the reflection density D value of a printed material, a portion having the highest D value was used. Similarly, in the measurement of the light resistance test and the ozone gas resistance test, which are items to be evaluated using a colorimeter, the gradation portion where the reflection density D value of the printed material before the test is closest to 1.0 is selected. And measured. For the hue evaluation, the humidity resistance test, and the color rendering test, the entire printed matter was visually evaluated.

(C) Evaluation of recorded image
For the recorded image by the aqueous ink composition of the present invention, the hue, hue density, hue change after light resistance test, hue change after ozone gas resistance test, degree of bleeding by moisture resistance test, and color rendering properties are evaluated. went. Note that the ozone gas resistance test and the moisture resistance test were performed only on the dedicated glossy papers A and B. The results are shown in (Table 6). The test method is shown below.
(1) Hue density evaluation The hue density of the recorded image was measured using Gretag Macbeth SpectroEye (manufactured by GRETAG), and the hue density D value was calculated. The criteria are shown below.
○ Plain paper: 1.2 ≦ D Glossy paper: 2.2 ≦ D
Δ Plain paper: 1.0 ≦ D <1.2 Glossy paper: 1.9 ≦ D <2.2
× Plain paper: D <1.0 Glossy paper: D <1.2
(2) Light resistance test Using a xenon weatherometer Ci4000 (manufactured by ATLAS), the printed sample was irradiated with an illuminance of 0.36 W / square meter for 50 hours. After the test, the color was measured in the same manner as described above, and the color difference (ΔE) and the residual ratio of hue density before and after the test were measured. The determination was made according to the following criteria.
○ ΔE: Less than 10 and remaining rate: 80% or more ΔΔE: Only one of the remaining rates cannot satisfy the condition of ○ × ΔE: 10 or more and remaining rate: less than 80% (3) Ozone resistant gas 3. Possibility test Using an ozone weather meter (manufactured by Suga Test Instruments Co., Ltd.), the print sample was left for 1 hour at an ozone concentration of 12 ppm, a humidity of 60% RH, and a temperature of 24 ° C. After the test, the color was measured in the same manner as described above, and the color difference (ΔE) and the residual ratio of hue density before and after the test were measured. The determination was made according to the following criteria.
○ ΔE: Less than 15 and remaining rate: 80% or more Δ ΔE or only the remaining rate cannot satisfy the condition of ○ × ΔE: 15 or more and remaining rate: less than 80% (4) Moisture resistance Test The printed sample was allowed to stand at 50 ° C. and 90% RH for 3 days using a thermo-hygrostat (manufactured by Applied Giken Sangyo Co., Ltd.), and the dye bleeding before and after the test was visually determined.
○ Dye bleeding is hardly seen. △ Dye bleeding is slightly seen. × Dye bleeding is considerably seen.
(5) Color rendering test The degree of discoloration when viewed under tungsten light was visually determined based on the hue under a standard light source.
○ Hue change is small.
△ Hue change is slightly large.
× Hue change is large.

Comparative Example 1
C. of an azo dye used as a black dye for water-soluble inkjet as a comparison target. I. An ink composition was prepared using Food Black 2 (formula (32) below) having the same ink composition as in Example 3. The results of hue evaluation, hue density evaluation, light resistance evaluation, ozone gas resistance evaluation, moisture resistance evaluation and color rendering evaluation of the obtained recorded image are shown in Table 6.

Comparative Example 2
Similarly, an ink composition having the same ink composition as in Example 3 was prepared using the dye shown in Example 2 of Patent Document 5 (formula (33) below) as a water-soluble inkjet dye for comparison. The results of hue evaluation, hue density evaluation, light resistance evaluation, ozone gas resistance evaluation, moisture resistance evaluation and color rendering evaluation of the obtained recorded image are shown in Table 6.

Comparative Example 3
Similarly, an ink composition having the same ink composition as that of Example 3 was prepared using the dye shown in Example 3 of Patent Document 6 (formula (34) below) as a water-soluble inkjet dye for comparison. The results of hue evaluation, hue density evaluation, light resistance evaluation, ozone gas resistance evaluation, moisture resistance evaluation and color rendering evaluation of the obtained recorded image are shown in Table 6.

(Table 6)
Hue Concentration Light Resistance Ozone Gas Resistance Moisture Resistance Color Rendering Example 3 (Formula (29))
Plain paper ○ ○ − − ○
Exclusive glossy paper A ○ ○ ○ ○ ○
Exclusive glossy paper B ○ ○ ○ ○ ○
Example 4 (Formula (31))
Plain paper ○ ○ − − ○
Exclusive glossy paper A ○ ○ ○ ○ ○
Exclusive glossy paper B ○ ○ ○ ○ ○
Comparative Example 1 (Formula (32))
Plain paper ○ ○ − − ×
Exclusive glossy paper A △ ○ × × ×
Exclusive glossy paper B △ ○ × × ×
Comparative Example 2 (Formula (33))
Plain paper ○ ○ − − ×
Exclusive glossy paper A ○ △ × △ ×
Exclusive glossy paper B ○ ○ △ ○ ×
Comparative Example 3 (Formula (34))
Plain paper ○ ○ ×
Exclusive glossy paper A ○ ○ × ○ ×
Exclusive glossy paper B ○ ○ △ ○ ×

From Table 6, the ink composition containing the azo compound of the present invention is excellent in hue, ozone gas resistance, light resistance, moisture resistance, and color rendering as compared with the conventional black dye (comparative example).

The ink composition containing the azo compound of the present invention is used as a black ink liquid for ink jet recording and writing instruments.

Claims (7)

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

(In the formula (1), R ¹ to R ⁶ are optional substituents, A and B each represent a single bond, the substitution position of the bond A is 2 or 3, and the substitution position of the bond B is 2 ′ or 3 ′ position, l is 1 or 2, and m and n are 0 or 1. The substitution position of (SO ₃ H) m is the 3 or 4 position, and the substitution position of (SO ₃ H) n is 3 An ink composition characterized by containing at least one kind of 'or 4'-position). In the formula (1), R ¹ to R ³ are hydrogen, halogen atom, cyano group, hydroxy group, amino group, carboxyl group, sulfo group, sulfamoyl group which may be substituted with alkyl group or phenyl group, phosphate group; Nitro group; acyl group; phenyl group; ureido group; hydroxy group or (C1-C4) alkyl group optionally substituted with (C1-C4) alkoxy group; hydroxy group, (C1-C4) alkoxy group, sulfo group or (C1-C4) alkoxy group optionally substituted by a carboxyl group; amino group substituted by a phenyl group optionally further substituted by a carboxyl group or a sulfo group; amino substituted by an alkyl group or an acyl group a group, R ⁴ is hydrogen; hydroxy group, (C1 -C4) alkoxy group, sulfo Motowaka verses It may be substituted with a carboxyl group (C1 -C4) alkyl group; an amino group, an alkyl group, an alkoxy group, a phenyl group which may be substituted with a carboxyl group or a sulfo group, R ⁵ and R ⁶ are hydrogen; A sulfo group; an acetylamino group; a hydroxy group or a (C1-C4) alkyl group optionally substituted with a (C1-C4) alkoxy group; a hydroxy group, a (C1-C4) alkoxy group, a sulfo group or a carboxyl group; The ink composition according to claim 1, which may be a (C1-C4) alkoxy group. The compound of formula (1) is an azo compound represented by the following formula (1a) or a salt thereof

(In the formula (1a), R ^{1 to} R ³ are a sulfo group, a carboxyl group, a methyl group or a methoxy group, R ⁵ and R ⁶ are (C1 to C4) alkyl groups; a hydroxy group or a sulfo group may be substituted. (C1-C4) alkoxy group, the substitution position of bond B is 2 ′ or 3 ′ position)
The ink composition according to claim 1, wherein The ink composition according to any one of claims 1 to 3, wherein the salt is a lithium salt, a sodium salt, a potassium salt, an ammonium salt, or an ammonium salt represented by the general formula (2).

(In formula (2), Z ¹ , Z ² , Z ³ and Z ⁴ each independently represent a hydrogen atom, an alkyl group, a hydroxyalkyl group or a hydroxyalkoxyalkyl group.) An ink jet printer loaded with the ink composition according to any one of claims 1 to 4. A colored body colored by the ink jet printer according to claim 5. An azo compound represented by the formula (1b) or a salt thereof.

(In the formula (1b), R ¹ to R ³ are hydrogen; halogen atom; cyano group; hydroxy group; amino group; carboxyl group; sulfo group; sulfamoyl group optionally substituted with alkyl group or phenyl group; Nitro group; acyl group; phenyl group; ureido group; hydroxy group or (C1-C4) alkyl group optionally substituted with (C1-C4) alkoxy group; hydroxy group, (C1-C4) alkoxy group, sulfo group Or a (C1-C4) alkoxy group which may be substituted with a carboxyl group; an amino group substituted with a phenyl group which may be further substituted with a carboxyl group or a sulfo group; substituted with an alkyl group or an acyl group an amino group, R ⁴ is hydrogen; hydroxy group, (C1 -C4) alkoxy group, sulfo Motowaka Ku which may be substituted with a carboxyl group (C1 -C4) alkyl group; an amino group, an alkyl group, an alkoxy group, a phenyl group which may be substituted with a carboxyl group or a sulfo group, R ⁵ and R ⁶ Hydrogen; sulfo group; acetylamino group; hydroxy group or (C1-C4) alkyl group optionally substituted with (C1-C4) alkoxy group; hydroxy group, (C1-C4) alkoxy group, sulfo group or carboxyl group An optionally substituted (C1-C4) alkoxy group, wherein the bond A is substituted at the 2 or 3 position, the bond B is substituted at the 2 'or 3' position, l is 1 or 2, m and n Is 0 or 1. The substitution position of (SO ₃ H) m is the 3 or 4 position, and the substitution position of (SO ₃ H) n is the 3 ′ or 4 ′ position.