JP2005097359A - Water ink, ink for inkjet recording and method for inkjet recording - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide water-soluble ink (particularly ink for inkjet recording) which produces an image having a favorable hue and a high fastness against light and active gases in the atmosphere, particularly ozone gas and a method for inkjet recording. <P>SOLUTION: The water-soluble ink contains an azo dye which has at least one ionic hydrophilic group in the molecule and a specific structure having a heterocyclic ring as the skeleton. The ink for inkjet recording and the method for inkjet recording using the water-soluble ink are presented. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a novel aqueous ink, its use as an ink for ink jet recording, and an ink jet recording method.

The ink jet recording method is rapidly spreading and further developing because of its low material cost, high speed recording, low noise during recording, and easy color recording.
Inkjet recording methods include a continuous method in which droplets are continuously ejected and an on-demand method in which droplets are ejected in accordance with image information signals. There are a method of discharging bubbles, a method of generating bubbles in the ink by heat and discharging droplets, a method of using ultrasonic waves, and a method of sucking and discharging droplets by electrostatic force. As the ink for ink jet recording, water-based ink, oil-based ink, or solid (melted type) ink is used.

  For the colorant used in such ink for ink jet recording, the solvent has good solubility or dispersibility, high density recording is possible, hue is good, light, heat, environment It is robust against active gases (NOx, oxidizing gases such as ozone, SOx, etc.), has excellent fastness to water and chemicals, and has good fixability to image receiving materials and is difficult to bleed. The ink is required to have excellent storage stability, no toxicity, high purity, and availability at low cost. However, it is extremely difficult to search for colorants that meet these requirements at a high level. In particular, when printing on an image receiving material having an ink receiving layer that has a good hue and is robust against light, humidity, and heat, and especially contains porous white inorganic pigment particles. It is strongly desired to be robust against oxidizing gases such as ozone.

On the other hand, non-heterocyclic compounds such as phenol, naphthol, naphthylamine, and aniline have been widely used as raw materials for disazo dyes and trisazo dyes. As the disazo dyes obtained from these raw materials, the dyes disclosed in Patent Document 1, Patent Document 2, and the like are known, but all have the problem that light fastness is inferior, and oxidizing properties such as ozone. Fastness to gas is very poor.
In order to develop a colorant that is robust against oxidizing gases such as ozone, the present inventors have moved away from conventional raw materials such as phenol, naphthol, naphthylamine, and aniline, and mainly use heterocyclic compounds as raw materials. It came to the idea of doing. So far, oil-soluble dyes are described in Patent Document 3, Patent Document 4, and the like as disazo dyes and trisazo dyes containing two or more heterocyclic rings. A water-soluble dye having a heterocyclic ring is described in Patent Document 5.
However, a dye that satisfies the stability of the dye in the ink required for the colorant used in the inkjet recording ink and the above-mentioned various fastness properties has not been found so far.
European Patent No. 761771 Japanese Patent No. 2716541 German Patent 2743097 JP 59-133259 A JP-A-52-76331

An object of the present invention is to solve the conventional problems and achieve the following objects.
That is, an object of the present invention is to provide a colored image or coloring material having a good hue and excellent fastness, and to provide an aqueous ink for printing such as ink jet recording or writing.
Another object of the present invention is to provide an ink for ink jet recording and an ink jet recording method which have a good hue and can form an image having high fastness against light and an active gas in the environment, particularly ozone gas. There is.

The present inventors have studied in detail various dye compound derivatives aiming at dyes having a good hue and high fastness to light and ozone. The above problems are mainly caused by azo dyes having a heterocyclic skeleton. It was found that the point can be solved.
That is, according to the present invention, an aqueous ink, an ink jet recording ink and an ink jet recording method having the following constitution are provided, and the above object of the present invention is achieved.
1. A water-based ink comprising at least one dye represented by the following general formula (1) having at least one ionic hydrophilic group in a molecule.
General formula (1)

In general formula (1);
A represents an aromatic group which may be substituted or a heterocyclic group which may be substituted.
B ₁ and B ₂ each represent = CR ₁ -and -CR ₂ =, or either one represents a nitrogen atom and the other represents = CR ₁ -or -CR ₂ =.
G, R ₁ and R ₂ are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carboxyl group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, Heterocyclic oxycarbonyl group, acyl group, hydroxy group, alkoxy group, aryloxy group, heterocyclic oxy group, silyloxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, amino group (anilino group) A heterocyclic amino group), acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkyl or arylsulfonylamino group, heterocyclic sulfonylamino group, nitro group, alkyl and Arylchi Represents an o group, a heterocyclic thio group, an alkyl and arylsulfonyl group, a heterocyclic sulfonyl group, an alkyl and arylsulfinyl group, a heterocyclic sulfinyl group, a sulfamoyl group, or a sulfo group, and each group may be further substituted.
R ₃ represents a heterocyclic group. However, R ₃ is not a 2-thienyl group.
R ₄ and R ₅ each independently represents a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, an alkyl or arylsulfonyl group, or a sulfamoyl group. Each group may further have a substituent. However, R ₄ and R ₅ are not simultaneously hydrogen atoms.
R ₁ and R ₄ , or R ₄ and R ₅ may combine to form a 5- to 6-membered ring.
2. An ink for ink jet recording using the water-based ink according to claim 1.
3. An ink jet recording method comprising forming an image on an image receiving material having an ink receiving layer containing white inorganic pigment particles on a support using the ink for ink jet recording according to claim 2.

  The water-soluble ink of the present invention can give a colored image or coloring material excellent in hue and fastness. In particular, the ink for ink jet recording and the ink jet recording method using the water-based ink of the present invention are excellent in ink storage suitability, have a good hue, and are fast against active gases in the light and the environment, particularly ozone gas. High image quality can be formed.

Hereinafter, the present invention will be described in more detail.
[Azo dye]
The azo dye represented by the general formula (1) in the present invention will be described in detail.
First, groups and substituents constituting the general formula (1) will be described.

Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.
In this specification, an aliphatic group means an alkyl group, a substituted alkyl group, an alkenyl group, a substituted alkenyl group, an alkynyl group, a substituted alkynyl group, an aralkyl group, and a substituted aralkyl group. The aliphatic group may have a branch and may form a ring. The number of carbon atoms in the aliphatic group is preferably 1-20, and more preferably 1-16. The aryl moiety of the aralkyl group and substituted aralkyl group is preferably phenyl or naphthyl. Examples of aliphatic groups include methyl, ethyl, butyl, isopropyl, t-butyl, hydroxyethyl, methoxyethyl, cyanoethyl, trifluoromethyl, 3-sulfopropyl, 4-sulfobutyl, cyclohexyl group, benzyl group, 2-phenethyl Groups, vinyl groups, and allyl groups.

  In the present specification, the monovalent aromatic group means an aryl group and a substituted aryl group. The aryl group is preferably phenyl or naphthyl. The number of carbon atoms in the monovalent aromatic group is preferably 6-20, and more preferably 6-16. Examples of the monovalent aromatic group include phenyl, p-tolyl, p-methoxyphenyl, o-chlorophenyl and m- (3-sulfopropylamino) phenyl. The divalent aromatic group is a divalent version of these monovalent aromatic groups. Examples thereof include phenylene, p-tolylene, p-methoxyphenylene, o-chlorophenylene, and m- (3 -Sulfopropylamino) phenylene, naphthylene and the like.

  The heterocyclic group includes a heterocyclic group having a substituent and an unsubstituted heterocyclic group. The heterocyclic ring may be condensed with an aliphatic ring, an aromatic ring or another heterocyclic ring. As the heterocyclic group, a 5- or 6-membered heterocyclic group is preferable, and N, O, and S can be exemplified as the hetero atom of the heterocyclic ring. Examples of the substituent include aliphatic groups, halogen atoms, alkyl and arylsulfonyl groups, acyl groups, acylamino groups, sulfamoyl groups, carbamoyl groups, ionic hydrophilic groups and the like. Examples of the heterocyclic group include 2-pyridyl group, 3-pyridyl group, 4-pyridyl group, 2-thienyl group, 2-thiazolyl group, 4-thiazolyl group, 2-benzothiazolyl group, 2-benzoxazolyl group , 3-benzoindrenyl group, 2-imidazolyl group, 2-pyrrolyl group and 2-furyl group.

  The carbamoyl group includes a carbamoyl group having a substituent and an unsubstituted carbamoyl group. Examples of the substituent include an alkyl group. Examples of the carbamoyl group include a methylcarbamoyl group and a dimethylcarbamoyl group.

  The alkoxycarbonyl group includes an alkoxycarbonyl group having a substituent and an unsubstituted alkoxycarbonyl group. As the alkoxycarbonyl group, an alkoxycarbonyl group having 2 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group.

  The aryloxycarbonyl group includes an aryloxycarbonyl group having a substituent and an unsubstituted aryloxycarbonyl group. As the aryloxycarbonyl group, an aryloxycarbonyl group having 7 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of the aryloxycarbonyl group include a phenoxycarbonyl group.

The heterocyclic oxycarbonyl group includes a heterocyclic oxycarbonyl group having a substituent and an unsubstituted heterocyclic oxycarbonyl group. The heterocyclic oxycarbonyl group is preferably a heterocyclic oxycarbonyl group having 2 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the heterocyclic oxycarbonyl group include a 2-pyridyloxycarbonyl group.
The acyl group includes an acyl group having a substituent and an unsubstituted acyl group. The acyl group is preferably an acyl group having 1 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the acyl group include an acetyl group and a benzoyl group.

  The alkoxy group includes an alkoxy group having a substituent and an unsubstituted alkoxy group. As an alkoxy group, a C1-C20 alkoxy group is preferable. Examples of the substituent include an alkoxy group, a hydroxyl group, and an ionic hydrophilic group. Examples of the alkoxy group include a methoxy group, an ethoxy group, an isopropoxy group, a methoxyethoxy group, a hydroxyethoxy group, and a 3-carboxypropoxy group.

  The aryloxy group includes an aryloxy group having a substituent and an unsubstituted aryloxy group. The aryloxy group is preferably an aryloxy group having 6 to 20 carbon atoms. Examples of the substituent include an alkoxy group and an ionic hydrophilic group. Examples of the aryloxy group include a phenoxy group, a p-methoxyphenoxy group, and an o-methoxyphenoxy group.

  The heterocyclic oxy group includes a heterocyclic oxy group having a substituent and an unsubstituted heterocyclic oxy group. As the heterocyclic oxy group, a heterocyclic oxy group having 2 to 20 carbon atoms is preferable. Examples of the substituent include an alkyl group, an alkoxy group, and an ionic hydrophilic group. Examples of the heterocyclic oxy group include a 3-pyridyloxy group and a 3-thienyloxy group.

  The silyloxy group is preferably a silyloxy group substituted with an aliphatic group or aromatic group having 1 to 20 carbon atoms. Examples of the silyloxy group include trimethylsilyloxy and diphenylmethylsilyloxy.

  The acyloxy group includes an acyloxy group having a substituent and an unsubstituted acyloxy group. As the acyloxy group, an acyloxy group having 1 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of the acyloxy group include an acetoxy group and a benzoyloxy group.

  The carbamoyloxy group includes a carbamoyloxy group having a substituent and an unsubstituted carbamoyloxy group. Examples of the substituent include an alkyl group. Examples of the carbamoyloxy group include an N-methylcarbamoyloxy group.

  The alkoxycarbonyloxy group includes an alkoxycarbonyloxy group having a substituent and an unsubstituted alkoxycarbonyloxy group. As the alkoxycarbonyloxy group, an alkoxycarbonyloxy group having 2 to 20 carbon atoms is preferable. Examples of the alkoxycarbonyloxy group include a methoxycarbonyloxy group and an isopropoxycarbonyloxy group.

  The aryloxycarbonyloxy group includes an aryloxycarbonyloxy group having a substituent and an unsubstituted aryloxycarbonyloxy group. The aryloxycarbonyloxy group is preferably an aryloxycarbonyloxy group having 7 to 20 carbon atoms. Examples of the aryloxycarbonyloxy group include a phenoxycarbonyloxy group.

The amino group includes an amino group substituted with an alkyl group, an aryl group or a heterocyclic group, and the alkyl group, aryl group and heterocyclic group may further have a substituent. As the alkylamino group, an alkylamino group having 1 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of the alkylamino group include a methylamino group and a diethylamino group.
The arylamino group includes an arylamino group having a substituent, an unsubstituted arylamino group, and an anilino group. The arylamino group is preferably an arylamino group having 6 to 20 carbon atoms. Examples of the substituent include a halogen atom and an ionic hydrophilic group. Examples of the arylamino group include a phenylamino group and a 2-chlorophenylamino group.
The heterocyclic amino group includes a heterocyclic amino group having a substituent and an unsubstituted heterocyclic amino group. As the heterocyclic amino group, a heterocyclic amino group having 2 to 20 carbon atoms is preferable. Examples of the substituent include an alkyl group, a halogen atom, and an ionic hydrophilic group.

  The acylamino group includes an acylamino group having a substituent and an unsubstituted acylamino group. The acylamino group is preferably an acylamino group having 2 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the acylamino group include an acetylamino group, a propionylamino group, a benzoylamino group, an N-phenylacetylamino group, and a 3,5-disulfobenzoylamino group.

  The ureido group includes a ureido group having a substituent and an unsubstituted ureido group. The ureido group is preferably a ureido group having 1 to 20 carbon atoms. Examples of the substituent include an alkyl group and an aryl group. Examples of the ureido group include a 3-methylureido group, a 3,3-dimethylureido group, and a 3-phenylureido group.

  The sulfamoylamino group includes a sulfamoylamino group having a substituent and an unsubstituted sulfamoylamino group. Examples of the substituent include an alkyl group. Examples of the sulfamoylamino group include N, N-dipropylsulfamoylamino group.

  The alkoxycarbonylamino group includes an alkoxycarbonylamino group having a substituent and an unsubstituted alkoxycarbonylamino group. As the alkoxycarbonylamino group, an alkoxycarbonylamino group having 2 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of the alkoxycarbonylamino group include an ethoxycarbonylamino group.

  The aryloxycarbonylamino group includes an aryloxycarbonylamino group having a substituent and an unsubstituted aryloxycarbonylamino group. The aryloxycarbonylamino group is preferably an aryloxycarbonylamino group having 7 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the aryloxycarbonylamino group include a phenoxycarbonylamino group.

  The alkyl and arylsulfonylamino groups include substituted alkyl and arylsulfonylamino groups, and unsubstituted alkyl and arylsulfonylamino groups. As the sulfonylamino group, a sulfonylamino group having 1 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of these sulfonylamino groups include a methylsulfonylamino group, an N-phenyl-methylsulfonylamino group, a phenylsulfonylamino group, and a 3-carboxyphenylsulfonylamino group.

  The heterocyclic sulfonylamino group includes a heterocyclic sulfonylamino group having a substituent and an unsubstituted heterocyclic sulfonylamino group. The heterocyclic sulfonylamino group is preferably a heterocyclic sulfonylamino group having 1 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the heterocyclic sulfonylamino group include a 2-thiophenesulfonylamino group and a 3-pyridinesulfonylamino group.

  The heterocyclic sulfonyl group includes a heterocyclic sulfonyl group having a substituent and an unsubstituted heterocyclic sulfonyl group. The heterocyclic sulfonyl group is preferably a heterocyclic sulfonyl group having 1 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the heterocyclic sulfonyl group include a 2-thiophenesulfonyl group and a 3-pyridinesulfonyl group.

  The heterocyclic sulfinyl group includes a heterocyclic sulfinyl group having a substituent and an unsubstituted heterocyclic sulfinyl group. The heterocyclic sulfinyl group is preferably a heterocyclic sulfinyl group having 1 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the heterocyclic sulfinyl group include a 4-pyridinesulfinyl group.

  The alkyl, aryl and heterocyclic thio groups include substituted alkyl, aryl and heterocyclic thio groups and unsubstituted alkyl, aryl and heterocyclic thio groups. Alkyl, aryl and heterocyclic thio groups are preferably those having 1 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the alkyl, aryl and heterocyclic thio groups include a methylthio group, a phenylthio group, and a 2-pyridylthio group.

  The alkyl and arylsulfonyl groups include substituted alkyl and arylsulfonyl groups, unsubstituted alkyl and arylsulfonyl groups. Examples of alkyl and arylsulfonyl groups include methylsulfonyl and phenylsulfonyl groups, respectively.

  Alkyl and arylsulfinyl groups include substituted alkyl and arylsulfinyl groups, unsubstituted alkyl and arylsulfinyl groups. Examples of alkyl and arylsulfinyl groups include methylsulfinyl group and phenylsulfinyl group, respectively.

  The sulfamoyl group includes a sulfamoyl group having a substituent and an unsubstituted sulfamoyl group. Examples of the substituent include an alkyl group. Examples of the sulfamoyl group include a dimethylsulfamoyl group and a di- (2-hydroxyethyl) sulfamoyl group.

General formula (1) will be further described.
In the following description, what has already been described applies to the group and the substituent.
In the general formula (1), A represents an aromatic group which may be substituted or a heterocyclic group which may be substituted. Examples of the aromatic ring include a benzene ring and a naphthalene ring, and examples of the hetero atom of the heterocyclic ring include N, O, and S. The heterocyclic ring may be condensed with an aliphatic ring, an aromatic ring or another heterocyclic ring.
The substituent may be an arylazo group or a heterocyclic azo group.

B ₁ and B ₂ each represent = CR ₁ -and -CR ₂ =, or either one represents a nitrogen atom and the other represents = CR ₁ -or -CR ₂ =, but each represents = CR _1- , -CR ₂ = is more preferable.
R ₄ and R ₅ each independently represents a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, an alkyl or arylsulfonyl group, or a sulfamoyl group. Each group may further have a substituent. Preferable substituents represented by R ₄ and R ₅ include a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkyl or arylsulfonyl group. More preferably, they are a hydrogen atom, an aromatic group, a heterocyclic group, an acyl group, an alkyl or arylsulfonyl group. Most preferably, they are a hydrogen atom, an aryl group, and a heterocyclic group. Each group may further have a substituent. However, R ₄ and R ₅ are not simultaneously hydrogen atoms.

G, R ₁ and R ₂ are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carboxyl group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, Heterocyclic oxycarbonyl group, acyl group, hydroxy group, alkoxy group, aryloxy group, heterocyclic oxy group, silyloxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, amino group (anilino group) A heterocyclic amino group), acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkyl or arylsulfonylamino group, heterocyclic sulfonylamino group, nitro group, alkyl and An arylthio group, Heterocyclic thio group, an alkylsulfonyl group, a heterocyclic sulfonyl group, an alkyl- or arylsulfinyl group, heterocyclic sulfinyl group, a sulfamoyl group or a sulfo group, and each group may be further substituted.

  Examples of the substituent represented by G include a hydrogen atom, halogen atom, aliphatic group, aromatic group, hydroxy group, alkoxy group, aryloxy group, acyloxy group, heterocyclic oxy group, amino group (anilino group, heterocyclic ring). (Including amino groups), acylamino groups, ureido groups, sulfamoylamino groups, alkoxycarbonylamino groups, aryloxycarbonylamino groups, alkyl and arylthio groups, or heterocyclic thio groups, more preferably hydrogen atoms or halogen atoms. , An alkyl group, a hydroxy group, an alkoxy group, an aryloxy group, an acyloxy group, an amino group (including an anilino group and a heterocyclic amino group) or an acylamino group, among which a hydrogen atom, an anilino group and an acylamino group are most preferable. Each group may further have a substituent.

Preferable substituents represented by R ₁ and R ₂ include a hydrogen atom, an alkyl group, a halogen atom, an alkoxycarbonyl group, a carboxyl group, a carbamoyl group, a hydroxy group, an alkoxy group, and a cyano group. Each group may further have a substituent.
R ₁ and R ₄ , or R ₄ and R ₅ may combine to form a 5- to 6-membered ring.
Examples of the substituent in the case where each of the substituents represented by A, R ₁ , R ₂ , R ₄ , R ₅ , and G further has a substituent include the substituents exemplified for G, R ₁ , and R ₂ above. be able to. Moreover, it is preferable to have an ionic hydrophilic group as a substituent at any position on A, R ₁ , R ₂ , R ₄ , R ₅ and G.
Examples of the ionic hydrophilic group as a substituent include a sulfo group, a carboxyl group, a phosphono group, and a quaternary ammonium group. As the ionic hydrophilic group, a carboxyl group, a phosphono group, and a sulfo group are preferable, and a carboxyl group and a sulfo group are particularly preferable. The carboxyl group, phosphono group, and sulfo group may be in the form of a salt. Examples of counter ions that form a salt include ammonium ions, alkali metal ions (eg, lithium ions, sodium ions, potassium ions), and organic cations. (Eg, tetramethylammonium ion, tetramethylguanidinium ion, tetramethylphosphonium).
The dyes of specific examples 93, 94 and 95 described in JP-A-52-76331 as a similar structure of the general formula (1) of the present invention have few water-soluble groups and have sufficient solubility for use as water-based inks. I can't get it.

Preferred heterocyclic groups represented by R ₃ are as described in the above description of the heterocyclic ring (excluding the 2-thienyl group), more preferably a 2-pyridyl group, a 3-pyridyl group, and a 4-pyridyl group. 2-thiazolyl group, 4-thiazolyl group, 3-benzoindrenyl group, particularly preferably 2-pyridyl group, 3-pyridyl group, 4-pyridyl group or 2-thiazolyl group.

A particularly preferred combination of substituents as the azo dye represented by the general formula (1) is preferably a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, a sulfonyl group, or an acyl group as R ₄ and R ₅ . More preferred are a hydrogen atom, an aryl group, a heterocyclic group, and a sulfonyl group, and most preferred are a hydrogen atom, an aryl group, and a heterocyclic group. However, R ₄ and R ₅ are not both hydrogen atoms.
G is preferably a hydrogen atom, a halogen atom, an alkyl group, a hydroxyl group, an amino group, or an acylamino group, more preferably a hydrogen atom, a halogen atom, an amino group, or an acylamino group, most preferably a hydrogen atom, an amino group. Group, an acylamino group.
Among A, a pyrazole ring, an imidazole ring, an isothiazole ring, a thiadiazole ring, and a benzothiazole ring are preferable, a pyrazole ring and an isothiazole ring are further preferable, and a pyrazole ring is most preferable.
B ₁ and B ₂ are ═CR ₁ — and —CR ₂ ═, respectively, and R ₁ and R ₂ are preferably a hydrogen atom, an alkyl group, a halogen atom, a cyano group, a carbamoyl group, a carboxyl group, a hydroxyl group, respectively. , An alkoxy group and an alkoxycarbonyl group, and more preferably a hydrogen atom, an alkyl group, a carboxyl group, a cyano group and a carbamoyl group.
A is preferably an optionally substituted aromatic group. As examples of the aromatic ring, a benzene ring and a naphthalene ring are most preferable. Further, these are preferably further substituted with an ionic hydrophilic group, particularly preferably a carboxyl group or a sulfo group, and more preferably two or more ionic hydrophilic groups are substituted.

  In addition, about the preferable combination of a substituent of the compound represented by the said General formula (1), the compound whose at least 1 of a various substituent is the said preferable group is preferable, and many more various substituents are the said preferable. More preferred are compounds that are groups, and most preferred are compounds in which all substituents are the preferred groups.

  Specific examples of the azo dye represented by the general formula (1) are shown below, but the azo dye used in the present invention is not limited to the following examples, and also includes a carboxyl group, a phosphono group, and a sulfo group. May be in the form of a salt, and examples of counter ions that form salts include ammonium ions, alkali metal ions (eg, lithium ions, sodium ions, potassium ions) and organic cations (eg, tetramethylammonium ions, Tetramethylguanidinium ion, tetramethylphosphonium).

  The dye represented by the general formula (1) can be synthesized by a coupling reaction between a diazo component and a coupler. A synthesis example is shown below.

[Synthesis Example of Dye a-2]
2.5 g of diazo component A-2 was suspended in 30 ml of acetic acid and 60 ml of 85% phosphoric acid, and further 695 mg of 40% nitrosylsulfuric acid was added while maintaining the liquid temperature at -2 ° C to 0 ° C. This solution was added to a solution obtained by dissolving 2.5 g of coupler component B-2 in 122 ml of water while stirring, and reacted at 0 to 5 ° C. for 1 hour. 30 g of lithium chloride was added to the reaction solution, and the precipitated crystals were filtered and washed. The obtained wet cake was added to 100 ml of water, the pH was adjusted to 7-8 with a 0.1N lithium chloride aqueous solution, and 300 ml of isopropyl alcohol was added. The precipitated crystals were filtered and washed. This operation was performed again to obtain 2.5 g of the desired product. (M / S = 986, λmax (water) = 583 nm)
The synthesis route is shown below.

[Synthesis Example of Dye a-4]
1.8 g of diazo component A-4 was suspended in 22 ml of acetic acid and 44 ml of 85% phosphoric acid, and 472 mg of 40% nitrosylsulfuric acid was further added while maintaining the liquid temperature at -2 ° C to 0 ° C. This solution was added to a solution obtained by dissolving 1.7 g of coupler component B-2 in 87 ml of water while stirring, and reacted at 0 to 5 ° C. for 1 hour. 10 g of lithium chloride was added to the reaction solution, and the precipitated crystals were filtered and washed. The obtained wet cake was added to 100 ml of water, the pH was adjusted to 7-8 with a 0.1N lithium chloride aqueous solution, and 300 ml of isopropyl alcohol was added. The precipitated crystals were filtered and washed. This operation was performed again to obtain 2.0 g of the desired product. (M / S = 992, λmax (water) = 596 nm)
The synthesis route is shown below.

The ink for inkjet recording can be produced by dissolving and / or dispersing the azo dye in a lipophilic medium or an aqueous medium. Preferably, an aqueous medium is used. If necessary, other additives are contained within a range that does not impair the effects of the present invention. Other additives include, for example, anti-drying agents (wetting agents), anti-fading agents, emulsion stabilizers, penetration enhancers, ultraviolet absorbers, preservatives, anti-fungal agents, pH adjusters, surface tension adjusters, Well-known additives, such as a foaming agent, a viscosity modifier, a dispersing agent, a dispersion stabilizer, a rust preventive agent, a chelating agent, are mentioned.
These various additives are directly added to the ink liquid in the case of water-soluble ink. When the oil-soluble dye is used in the form of a dispersion, it is generally added to the dispersion after the preparation of the dye dispersion, but it may be added to the oil phase or the aqueous phase at the time of preparation.

The anti-drying agent is preferably used for the purpose of preventing clogging due to drying of the ink-jet ink at the ink jet port of the nozzle used in the ink-jet recording method.
As the drying inhibitor, a water-soluble organic solvent having a vapor pressure lower than that of water is preferable. Specific examples include ethylene glycol, propylene glycol, diethylene glycol, polyethylene glycol, thiodiglycol, dithiodiglycol, 2-methyl-1,3-propanediol, 1,2,6-hexanetriol, acetylene glycol derivatives, Polyhydric alcohols typified by glycerin, trimethylolpropane, etc., lower alkyl of polyhydric alcohols such as ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) ether, triethylene glycol monoethyl (or butyl) ether Ethers, 2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, heterocyclic rings such as N-ethylmorpholine, sulfolane, dimethyl sulfoxide, - sulfur-containing compounds such as sulfolane, diacetone alcohol, polyfunctional compounds such as diethanolamine, and urea derivatives. Of these, polyhydric alcohols such as glycerin and diethylene glycol are more preferred. Moreover, said drying inhibitor may be used independently and may be used together 2 or more types. These drying inhibitors are preferably contained in the ink in an amount of 10 to 50% by mass.

  The penetration enhancer is preferably used for the purpose of allowing the ink for inkjet to penetrate better into paper. As the penetration enhancer, alcohols such as ethanol, isopropanol, butanol, di (tri) ethylene glycol monobutyl ether, 1,2-hexanediol, sodium lauryl sulfate, sodium oleate, nonionic surfactants, etc. may be used. it can. If these are contained in the ink in an amount of 5 to 30% by mass, they usually have a sufficient effect, and it is preferable to use them in a range of addition amounts that do not cause printing bleeding and paper loss (print through).

  The ultraviolet absorber is used for the purpose of improving image storability. Examples of the ultraviolet absorber include benzotriazoles described in JP-A Nos. 58-185677, 61-190537, JP-A-2-782, JP-A-5-97075, JP-A-9-34057, and the like. Compounds, benzophenone compounds described in JP-A No. 46-2784, JP-A No. 5-194433, U.S. Pat. No. 3,214,463, etc., JP-B Nos. 48-30492, 56-21114, Cinnamic acid compounds described in JP-A-10-88106, JP-A-4-298503, JP-A-8-53427, JP-A-8-239368, JP-A-10-182621, JP-A-8 No. -502911, etc., triazine compounds, Research Disclosure No. Compounds described in No. 24239, compounds that emit fluorescence by absorbing ultraviolet rays typified by stilbene-based and benzoxazole-based compounds, so-called fluorescent brighteners, can also be 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. Organic anti-fading agents include hydroquinones, alkoxyphenols, dialkoxyphenols, phenols, anilines, amines, indanes, chromans, alkoxyanilines, heterocycles, etc. Complex, zinc complex and the like. More specifically, Research Disclosure No. No. 17643, Nos. VII to I, J; 15162, ibid. No. 18716, page 650, left column, ibid. No. 36544, page 527, ibid. No. 307105, page 872, ibid. The compounds described in the patent cited in No. 15162 and the compounds included in the general formulas and compound examples of the representative compounds described in pages 127 to 137 of JP-A-62-215272 can be used.

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

  As the pH adjuster, a neutralizer (organic base, inorganic alkali) can be used. For the purpose of improving the storage stability of the inkjet ink, the pH adjuster is preferably added to the inkjet ink for the summer of pH 6 to 10, and more preferably added to a pH of 7 to 10.

Examples of the surface tension adjusting agent include nonionic, cationic and anionic surfactants. The surface tension of the inkjet ink of the present invention is preferably 20 to 60 mN / m, and more preferably 25 to 45 mN / m. Further, the viscosity of the ink for inkjet recording of the present invention is preferably 30 mN / m or less. Furthermore, it is more preferable to adjust to 20 mN / m or less.
Examples of surfactants include fatty acid salts, alkyl sulfate esters, alkyl benzene sulfonates, alkyl naphthalene sulfonates, dialkyl sulfosuccinates, alkyl phosphate ester salts, naphthalene sulfonate formalin condensates, polyoxyethylene alkyl sulfates. Anionic surfactants such as ester salts, polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin fatty acid ester Nonionic surfactants such as oxyethyleneoxypropylene block copolymers are preferred. Further, SURFYNOLS (Air Products & Chemicals), which is an acetylene-based polyoxyethylene oxide surfactant, is also preferably used. An amine oxide type amphoteric surfactant such as N, N-dimethyl-N-alkylamine oxide is also preferred. Further, pages (37) to (38) of JP-A-59-157,636, Research Disclosure No. The surfactants described in 308119 (1989) can also be used.

  As the antifoaming agent, fluorine-based, silicone-based compounds, chelating agents represented by EDTA, and the like can be used as necessary.

  As the aqueous medium, a mixture containing water as a main component and optionally adding a water-miscible organic solvent can be used. Examples of water miscible organic solvents include alcohols (eg, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, t-butanol, pentanol, hexanol, cyclohexanol, benzyl alcohol), polyhydric alcohols (E.g., ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol), glycol derivatives (e.g., Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether Diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, triethylene glycol monomethyl ether, ethylene glycol diacetate, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether , Triethylene glycol monoethyl ether, ethylene glycol monophenyl ether), amines (eg, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenetriamine, Reethylenetetramine, polyethyleneimine, tetramethylpropylenediamine) and other polar solvents (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, sulfolane, 2-pyrrolidone, N-methyl-2- Pyrrolidone, N-vinyl-2-pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone, acetonitrile, acetone). In addition, the said water miscible organic solvent may use 2 or more types together.

  In 100 parts by mass of the inkjet recording ink of the present invention, the azo dye is preferably contained in an amount of 0.2 to 30 parts by mass. In the ink for inkjet recording of the present invention, other colorant may be used in combination with the azo dye. When two or more colorants are used in combination, the total content of the colorants is preferably within the above range.

The ink for inkjet recording of the present invention can be used not only for forming a single color image but also for forming a full color image. In order to form a full-color image, magenta color ink, cyan color ink, and yellow color ink can be used.
Any yellow dye can be used. For example, aryl or heteryl azo dyes having phenols, naphthols, anilines, heterocycles such as pyrazolone and pyridone, open-chain active methylene compounds, etc. as coupling components (hereinafter referred to as coupler components); Azomethine dyes having open chain active methylene compounds, etc .; methine dyes such as benzylidene dyes and monomethine oxonol dyes; quinone dyes such as naphthoquinone dyes and anthraquinone dyes, and other dye species Examples thereof include quinophthalone dyes, nitro / nitroso dyes, acridine dyes, and acridinone dyes.
Any applicable magenta dye can be used. For example, aryl or heteryl azo dyes having phenols, naphthols, anilines, heterocycles such as pyrazine, open-chain active methylene compounds, etc. as coupling components (hereinafter referred to as coupler components); Examples include azomethine dyes having methylene compounds and the like; anthrapyridone dyes.

  Any applicable cyan dye can be used. For example, aryl or heteryl azo dyes having phenols, naphthols, anilines and the like as coupler components; for example, azomethine dyes having phenols, naphthols, heterocyclic rings such as pyrrolotriazole as coupler components; cyanine dyes, oxonol dyes, Polymethine dyes such as merocyanine dyes; carbonium dyes such as diphenylmethane dyes, triphenylmethane dyes, xanthene dyes; phthalocyanine dyes; anthraquinone dyes; indigo / thioindigo dyes.

  Each of these dyes may exhibit yellow and cyan colors only after part of the chromophore is dissociated, and the counter cation in that case may be an alkali metal or an inorganic cation such as ammonium. Alternatively, it may be an organic cation such as pyridinium or quaternary ammonium salt, and may further be a polymer cation having them in a partial structure.

[Inkjet recording method]
In the ink jet recording method of the present invention, energy is supplied to the ink for ink jet recording, and a known image receiving material, that is, plain paper, resin-coated paper, such as JP-A-8-169172, JP-A-8-27693, JP-A-2-276670, JP-A-7-276789, JP-A-9-323475, JP-A-62-238783, JP-A-10-153989, JP-A-10-217473, JP-A-10-235995 10-337947, 10-217597, 10-337947, etc. Form images on inkjet paper, film, electrophotographic co-paper, fabric, glass, metal, ceramics, etc. To do.

  In forming an image, a polymer latex compound may be used in combination for the purpose of imparting glossiness or water resistance or improving weather resistance. The timing of applying the latex compound to the image receiving material may be before, after, or simultaneously with the application of the colorant. Therefore, even if the addition place is in the image receiving paper, It may be in ink or may be used as a liquid material of polymer latex alone. Specifically, JP-A-2002-166638, 2002-121440, 2002-154201, 2002-144696, 2002-80759, 2002-187342, and 2002-172774 The method described in the document can be preferably used.

Hereinafter, a recording paper and a recording film used for ink jet printing using the ink of the present invention will be described.
The support in recording paper and recording film is made of chemical pulp such as LBKP and NBKP, mechanical pulp such as GP, PGW, RMP, TMP, CTMP, CMPMP, CGP, and waste paper pulp such as DIP. Additives such as known pigments, binders, sizing agents, fixing agents, cationic agents, paper strength enhancers, etc. can be mixed and manufactured using various devices such as long net paper machines and circular net paper machines. is there. In addition to these supports, either synthetic paper or plastic film sheet may be used, and the thickness of the support is preferably 10 to 250 μm and the basis weight is preferably 10 to 250 g / m ² . The support may be provided with an ink receiving layer and a backcoat layer as they are, or after a size press or anchor coat layer is provided with starch, polyvinyl alcohol or the like, an ink receiving layer and a backcoat layer may be provided. Further, the support may be flattened by a calendar device such as a machine calendar, a TG calendar, or a soft calendar. In the present invention, as the support, paper and plastic films laminated on both sides with polyolefin (for example, polyethylene, polystyrene, polyethylene terephthalate, polybutene and copolymers thereof) are more preferably used. It is preferable to add a white pigment (for example, titanium oxide or zinc oxide) or a tinting dye (for example, cobalt blue, ultramarine blue, or neodymium oxide) to the polyolefin.

  The ink receiving layer provided on the support contains a pigment and an aqueous binder. As the pigment, a white pigment is preferable, and as the white pigment, calcium carbonate, kaolin, talc, clay, diatomaceous earth, synthetic amorphous silica, aluminum silicate, magnesium silicate, calcium silicate, aluminum hydroxide, alumina, lithopone, zeolite, Examples thereof include white inorganic pigments such as barium sulfate, calcium sulfate, titanium dioxide, zinc sulfide and zinc carbonate, and organic pigments such as styrene pigments, acrylic pigments, urea resins and melamine resins. As the white pigment contained in the ink receiving layer, porous inorganic pigments are preferable, and synthetic amorphous silica having a large pore area is particularly preferable. As the synthetic amorphous silica, either anhydrous silicic acid obtained by a dry production method or hydrous silicic acid obtained by a wet production method can be used, but it is particularly desirable to use hydrous silicic acid.

Examples of the aqueous binder contained in the ink receiving layer include water-soluble polyvinyl alcohol, silanol-modified polyvinyl alcohol, starch, cationized starch, casein, gelatin, carboxymethylcellulose, hydroxyethylcellulose, polyvinylpyrrolidone, polyalkylene oxide, polyalkylene oxide derivatives, and the like. Water-dispersible polymers such as water-soluble polymers, styrene butadiene latexes, and acrylic emulsions. These aqueous binders can be used alone or in combination of two or more. In the present invention, among these, polyvinyl alcohol and silanol-modified polyvinyl alcohol are particularly preferable in terms of adhesion to the pigment and resistance to peeling of the ink receiving layer.
The ink receiving layer can contain a mordant, a water resistance agent, a light resistance improver, a surfactant, and other additives in addition to the pigment and the aqueous binder.

The mordant added to the ink receiving layer is preferably immobilized. For that purpose, a polymer mordant is preferably used.
For the polymer mordant, JP-A-48-28325, 54-74430, 54-124726, 55-22766, 55-142339, 60-23850, 60-23835, 60-23852, 60-23853, 60-57836, 60-60643, 60-118834, 60-122940, 60-122941, 60-122942, 60- No. 235134, JP-A-1-161236, U.S. Pat.Nos. 2,484,430, 2,548,564, 3,148,061, 3,309,690, 4,115,124, 4,124,386, 4,193,800, 4,273,853, 4,282,305, It is described in each specification of the same No. 4450224. An image receiving material containing a polymer mordant described in JP-A-1-161236, pages 212 to 215 is particularly preferred. When the polymer mordant described in the publication is used, an image with excellent image quality is obtained and the light resistance of the image is improved.

  The water-proofing agent is effective for making the image water-resistant. As these water-proofing agents, cationic resins are particularly desirable. Examples of such cationic resins include polyamide polyamine epichlorohydrin, polyethyleneimine, polyamine sulfone, dimethyl diallyl ammonium chloride polymer, cationic polyacrylamide, colloidal silica, etc. Among these cationic resins, polyamide polyamine epichlorohydrin is particularly preferable. is there. The content of these cationic resins is preferably 1 to 15% by mass, particularly 3 to 10% by mass, based on the total solid content of the ink receiving layer.

  Examples of the light resistance improver include zinc sulfate, zinc oxide, hindered amine antioxidants, and benzotriazole ultraviolet absorbers such as benzophenone. Of these, zinc sulfate is particularly preferred.

  The surfactant functions as a coating aid, a peelability improver, a slippage improver or an antistatic agent. The surfactant is described in JP-A Nos. 62-173463 and 62-183457. An organic fluoro compound may be used in place of the surfactant. The organic fluoro compound is preferably hydrophobic. Examples of the organic fluoro compound include a fluorine-based surfactant, an oily fluorine-based compound (for example, fluorine oil), and a solid fluorine compound resin (for example, tetrafluoroethylene resin). The organic fluoro compounds are described in JP-B-57-9053 (columns 8 to 17), JP-A-61-20994, and 62-135826. Examples of other additives added to the ink receiving layer include pigment dispersants, thickeners, antifoaming agents, dyes, fluorescent whitening agents, preservatives, pH adjusters, matting agents, and hardening agents. . The ink receiving layer may be one layer or two layers.

  The recording paper and the recording film can be provided with a back coat layer, and examples of components that can be added to this layer include a white pigment, an aqueous binder, and other components. Examples of white pigments contained in the backcoat layer include light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, and aluminum silicate. White inorganic pigments such as 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 And organic pigments such as styrene plastic pigment, acrylic plastic pigment, polyethylene, microcapsule, urea resin and melamine resin.

  As the aqueous binder contained in the backcoat layer, styrene / maleate copolymer, styrene / acrylate copolymer, polyvinyl alcohol, silanol modified polyvinyl alcohol, starch, cationized starch, casein, gelatin, carboxymethylcellulose Water-soluble polymers such as hydroxyethyl cellulose and polyvinyl pyrrolidone, and water-dispersible polymers such as styrene butadiene latex and acrylic emulsion. Examples of other components contained in the backcoat layer include an antifoaming agent, an antifoaming agent, a dye, a fluorescent brightening agent, a preservative, and a water-proofing agent.

  Polymer latex may be added to the constituent layers (including the backcoat layer) of the ink jet 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. The polymer latex is described in JP-A Nos. 62-245258, 62-1316648, and 62-110066. When a polymer latex having a low glass transition temperature (40? Or less) is added to a layer containing a mordant, cracking and curling of the layer can be prevented. Also, curling can be prevented by adding a polymer latex having a high glass transition temperature to the backcoat layer.

  The ink of the present invention is not limited to an ink jet recording system, and is a known system, for example, a charge control system that discharges ink using electrostatic attraction, a drop-on-demand system (pressure) that uses the vibration pressure of a piezo element. Pulse method), acoustic ink jet method that converts electrical signal into acoustic beam and irradiates ink and uses ink to discharge ink, and thermal ink jet that heats ink to form bubbles and uses generated pressure Used for systems. Inkjet recording methods use 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 inks. The method is included.

EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples at all.
[Example 1]
(Preparation of ink liquid A)
After adding deionized water to the following components to make 1 liter, the mixture was stirred for 1 hour while being heated at 30 to 40 ° C. Thereafter, the pH was adjusted to 9 with KOH 10 mol / L, and the solution was filtered under reduced pressure with a microfilter having an average pore size of 0.25 μm to prepare ink liquid A.

Composition of ink liquid A:
25 g of dye (a-2) of the present invention
Diethylene glycol 20g
Glycerin 120g
230 g of diethylene glycol monobutyl ether
2-Pyrrolidone 80g
Triethanolamine 17.9g
Benzotriazole 0.06g
Surfynol TG 8.5g
PROXEL XL2 1.8g

(Preparation of ink liquids B to D)
Ink liquids B to D were prepared in the same manner as the ink liquid A, except that the dye was changed as shown in Table 6 below. Ink liquids 101 to 103 were prepared using comparative dyes 1 to 3 as shown in Table 6 as comparative ink liquids.

  When changing the dye, it was used so that the added amount of the dye was equimolar with respect to the ink liquid A. When two or more dyes were used in combination, equimolar amounts were used.

(Image recording and evaluation)
The following evaluation was performed on the ink jet ink composed of the above ink liquids A to D and the comparative ink liquids 101, 102, and 103. The results are shown in Table 6.
In Table 6, “paper dependency”, “water resistance”, “light resistance”, “dark heat storage stability”, and “ozone gas resistance” indicate that each inkjet ink is an inkjet printer (EPSON Co., Ltd.). PM-700C) was recorded on photo glossy paper (manufactured by EPSON PM photographic paper <Glossy> (KA420PSK, EPSON)) and then evaluated by the following method.

<Paper dependence>
The color tone of the image formed on the photo glossy paper and the image formed separately on the PPC plain paper are compared, and when the difference between the two images is small A (good), when the difference between the two images is large B (defect) was evaluated in two stages.

<Water resistance>
The photo glossy paper on which the image was formed was dried at room temperature for 1 hour, then immersed in deionized water for 10 seconds, and naturally dried at room temperature, and bleeding was observed. Evaluation was made in three stages, with A indicating no bleeding, B indicating slight bleeding, and C indicating large bleeding.

<Light resistance>
The photo glossy paper on which the image is formed is irradiated with xenon light (85000 lx) for 7 days using a weather meter (Atlas C.I65), and the image density before and after the xenon irradiation is measured using a reflection densitometer (X-Rite310TR). And measured as a dye residual ratio. The reflection density was measured at three points of 1, 1.5 and 2.0.
The evaluation was made in three stages, with A being a dye residual ratio of 70% or more at any concentration, A being 1 or 2 points being less than 70% B, and C being less than 70% at all concentrations.

<Dark heat preservation>
The photo glossy paper on which the image was formed was stored for 7 days under conditions of 80 ° C. and 15% RH, and the image density before and after storage was measured using a reflection densitometer (X-Rite310TR), and the dye residual ratio As evaluated. The dye residual rate is evaluated at three points of reflection density of 1, 1.5 and 2, and A is the case where the dye residual rate is 90% or more at any concentration, and B is the case where 1 or 2 points are less than 90%. , C was defined as less than 90% at all concentrations.

<Ozone gas resistance>
The photo glossy paper on which the image has been formed is left in a box set at an ozone gas concentration of 0.5 ± 0.1 ppm, room temperature and dark place for 7 days, and the image density before and after being left under ozone gas is measured by a reflection densitometer (X -Rite310TR), and evaluated as a dye residual ratio. The reflection density was measured at three points of 1, 1.5 and 2.0. The ozone gas concentration in the box was set using an ozone gas monitor (model: OZG-EM-01) manufactured by APPLICS.
The evaluation was made in three stages, with A being a dye residual ratio of 70% or more at any concentration, A being 1 or 2 points being less than 70% B, and C being less than 70% at all concentrations.

  As shown in Table 6, the images obtained from the ink liquids A to D of the present invention were clearer than the images obtained from the comparative ink liquids 101, 102, and 103. Further, images obtained using the ink liquids A to D of the present invention were excellent in light fastness and ozone gas resistance.

  Furthermore, using ink liquids A to D, an image was recorded on glossy paper for exclusive use of Superfine (MJA4S3P, manufactured by Seiko Epson Corporation) using an ink jet printer (PM-700C, manufactured by Seiko Epson Corporation). When the hue and light fastness of the obtained images were evaluated, the same results as in Table 6 were obtained.

[Example 2]
An image was printed on the inkjet paper photo glossy paper EX manufactured by Fuji Photo Film using the same ink prepared in Example 1, and evaluated in the same manner as in Example 1. Example 1 Similar results were obtained.

[Example 3]
The same ink produced in Example 1 is packed in a cartridge of an inkjet printer BJ-F850 (manufactured by CANON), and an image is printed on the photo glossy paper GP-301 of the same printer, and the same evaluation as in Example 1 is performed. As a result, the same results as in Example 1 were obtained.

Claims (3)

A water-based ink comprising at least one dye represented by the following general formula (1) having at least one ionic hydrophilic group in a molecule.
General formula (1)

In general formula (1);
A represents an aromatic group which may be substituted or a heterocyclic group which may be substituted.
B ₁ and B ₂ each represent = CR ₁ -and -CR ₂ =, or either one represents a nitrogen atom and the other represents = CR ₁ -or -CR ₂ =.
G, R ₁ and R ₂ are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carboxyl group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, Heterocyclic oxycarbonyl group, acyl group, hydroxy group, alkoxy group, aryloxy group, heterocyclic oxy group, silyloxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, amino group (anilino group) A heterocyclic amino group), acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkyl or arylsulfonylamino group, heterocyclic sulfonylamino group, nitro group, alkyl and Arylchi Represents an o group, a heterocyclic thio group, an alkyl and arylsulfonyl group, a heterocyclic sulfonyl group, an alkyl and arylsulfinyl group, a heterocyclic sulfinyl group, a sulfamoyl group, or a sulfo group, and each group may be further substituted.
R ₃ represents a heterocyclic group. However, R ₃ is not a 2-thienyl group.
R ₄ and R ₅ each independently represents a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, an alkyl or arylsulfonyl group, or a sulfamoyl group. Each group may further have a substituent. However, R ₄ and R ₅ are not simultaneously hydrogen atoms.
R ₁ and R ₄ , or R ₄ and R ₅ may combine to form a 5- to 6-membered ring.   An ink for ink jet recording using the water-based ink according to claim 1.   An ink jet recording method comprising forming an image on an image receiving material having an ink receiving layer containing white inorganic pigment particles on a support using the ink for ink jet recording according to claim 2.