JP2009102544A - Azo pigment and azo pigment dispersed element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide azo pigment having excellent color characteristics such as tinting strength, hue or the like and excellent durability such as light fastness or the like and to provide an azo pigment dispersed element. <P>SOLUTION: The azo pigment is expressed in formula (1) (wherein, R<SB>1</SB>denotes aliphatic group, aryl group or heterocycle group, R<SB>2</SB>denotes hydrogen atom or aliphatic group, R<SB>3</SB>denotes aliphatic group, R<SB>4</SB>denotes aliphatic group or aryl group, X<SB>1</SB>denotes nitrogen atom, C-R<SB>5</SB>, R<SB>5</SB>denotes cyano group, carbamoyl group, aliphatic oxycarbonyl group, carboxyl group or sulfonyl group, and R<SB>6</SB>denotes hydrogen atom or aliphatic group) and the pigment dispersed element contains this azo pigment. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a novel nitrogen-containing heterocyclic azo pigment and a pigment dispersion containing the azo pigment.

  Conventionally, since azo dyes often have various visible light absorptions, they have been used as dyes in various fields. For example, it has come to be used in various fields such as coloring of synthetic resins, printing inks, dyes for sublimation thermal transfer materials, inkjet inks, and color filter dyes. An absorption spectrum is a large performance required for an azo dye as a dye. The hue of the pigment greatly affects the color and texture of an object colored by the pigment, and has a great effect on vision. Therefore, research on the absorption spectrum of dyes has been conducted for a long time.

  In recent years, color images have become mainstream as image recording materials, and the usage of dyes has also diversified. Specifically, ink-jet recording materials and printing inks are used as dyes and pigments, thermal transfer recording materials are used as dyes, electrophotographic recording materials, transfer-type silver halide photosensitive materials, and the like. . In addition, in photographing devices such as CCDs and in displays, LCDs and PDPs are used as color filters for dyes and pigments in order to record and reproduce color images. Furthermore, it is also used for dyeing hair as a dye. In these color image recording materials and color filters, three primary colorants (dyes and pigments) of a so-called additive color mixture method and subtractive color mixture method are used to reproduce or record a full color image. However, the present situation is that there is no colorant that has an absorption characteristic capable of realizing a preferable color reproduction range and can withstand various use conditions and environmental conditions, and has a good hue and a strong color, and improvement is strongly desired.

  On the other hand, it is known as a well-known fact that when a pigment is used as a pigment, its fastness is increased. The pigments used in each of the above applications must have the following properties in common. That is, having favorable absorption characteristics in terms of color reproducibility, having a particle size and particle shape necessary for expressing desired transparency, fastness under environmental conditions used, such as light resistance, heat resistance, Good resistance to oxidative gases such as ozone, chemical resistance to other organic solvents and sulfurous acid gas, etc., and dispersion of fine particles in the medium used, and stable dispersion. , Etc. In particular, there is a strong demand for pigments that have a good yellow hue in various applications and are strong against light, wet heat, and active gases in the environment, especially oxidizing gases such as ozone. Examples of yellow pigments include C.I. I. P. Y-74, C.I. I. P. Y-128 and the like are used in various applications, but they are not satisfactory because they have low fastness and a short hue, and improvements are desired. Further, as a yellow pigment having relatively high fastness, C.I. I. P. Y-150 and the like are known, but are pigments containing heavy metals, which are not preferable from the viewpoint of environmental conservation, and an alternative is desired.

  Azo pigments are widely used in printing inks, inkjet inks, electrophotographic materials, color toners, and the like because they are excellent in hue and coloring power, which are color characteristics. Of these, the most typically used yellow azo pigments are diarylide pigments. Examples of diarylide pigments include C.I. I. Pigment Yellow 12, 13 and 17 and the like. However, since diarylide pigments are very inferior in fastness, especially light resistance, when the printed matter is exposed to light, the pigment is decomposed and discolored, which is not suitable for long-term storage of the printed matter.

  In order to improve such defects, azo pigments having improved fastness by increasing the molecular weight or introducing a group having a strong intermolecular interaction are also disclosed (for example, Patent Documents 1 to 3). 3). However, even in the improved pigment, for example, the pigment described in Patent Document 1 has improved light resistance, but is still insufficient. For example, the pigment described in Patent Documents 2 and 3 has a green hue. There was a drawback that coloring power was lowered by taste and color characteristics were inferior.

  Moreover, although the pigment | dye of patent documents 4-5 was developed in order to improve a hue and fastness, since these pigment | dyes are oil-soluble pigment | dye, solvent resistance is low and fastness is not enough. There wasn't.

When full color is expressed using the subtractive color mixing method of three colors of yellow, magenta and cyan, or four colors with black added, if a pigment with poor fastness is used as the yellow pigment, the printed matter will be printed over time. If a pigment having a poor color characteristic is used, the color reproducibility during printing is deteriorated. Therefore, in order to obtain a printed matter that maintains a high color reproducibility for a long period of time, a yellow pigment and a pigment dispersion having both color characteristics and fastness are desired.
A conventionally known azo dye having a nitrogen-containing 5-membered ring as an azo component is also disclosed in Patent Document 6.
JP-A-56-38354 U.S. Pat. No. 2,936,306 Japanese Patent Laid-Open No. 11-1000051 JP 2005-213357 A Japanese Patent Laying-Open No. 2005-215286 JP-A-55-161856

  An object of the present invention is to provide an azo pigment and a pigment dispersion which are excellent in color characteristics such as coloring power and hue, and excellent in durability such as light resistance.

  As a result of extensive research, the present inventors have obtained knowledge that a specific nitrogen-containing heterocyclic azo pigment has a good hue and exhibits good fastness to light, heat and ozone. It was. Specific means for solving the above problems will be described below.

[1]
An azo pigment represented by the following general formula (1), a salt, a hydrate, and a tautomer thereof.

(In the general formula (1), R ₁ represents an aliphatic group, an aryl group or a heterocyclic group, R ₂ represents a hydrogen atom or an aliphatic group, R ₃ represents an aliphatic group, and R ₄ represents .X ₁ which represents an aliphatic group or an aryl group nitrogen atom, represents a C-R ₅ .R ₅ is a cyano group, a carbamoyl group, an aliphatic oxycarbonyl group, .R ₆ is hydrogen atom a carboxyl group or a sulfonyl group Or represents an aliphatic group.)
[2]
The azo pigment represented by the general formula (1) is represented by the following general formula (2) or (3), the azo pigment according to [1], a salt thereof, a hydrate, and a mixture thereof. Mutant body.

(In General Formula (2), R ₁ represents an aliphatic group, an aryl group, or a heterocyclic group, R ₂ represents a hydrogen atom or an aliphatic group, R ₃ represents an aliphatic group, and R ₄ represents Represents an aliphatic group or an aryl group, and R ₇ represents a cyano group, a carbamoyl group or an aliphatic oxycarbonyl group.
[3]
A pigment dispersion comprising at least one of the azo pigment, the salt, the hydrate and the tautomer thereof according to [1] or [2].

The azo pigment of the present invention is excellent in color characteristics such as high coloring power and hue, and also in durability such as light resistance and ozone resistance.
Furthermore, the pigment dispersion of the present invention is obtained by dispersing the azo pigment of the present invention in various media and is excellent in color characteristics, durability and dispersion stability.

First, the aliphatic group, aryl group, heterocyclic group and substituent in the present invention will be described.
In the aliphatic group in the present invention, the aliphatic moiety may be linear, branched or cyclic. Moreover, it may be saturated or unsaturated. Specific examples include an alkyl group, an alkenyl group, a cycloalkyl group, and a cycloalkenyl group. Furthermore, the aliphatic group may be unsubstituted or may have a substituent.

  The aryl group may be a single ring or a condensed ring. Further, it may be unsubstituted or may have a substituent. Moreover, the heterocyclic group should just have a hetero atom (for example, a nitrogen atom, a sulfur atom, an oxygen atom) in the ring, and even if it is a saturated ring, it is an unsaturated ring. Also good. Further, it may be a single ring or a condensed ring, and may be unsubstituted or have a substituent.

  Further, the substituent in the present invention may be any group that can be substituted. For example, an aliphatic group, an aryl group, a heterocyclic group, an acyl group, an acyloxy group, an acylamino group, an aliphatic oxy group, an aryloxy group, a hetero group Ring oxy group, aliphatic oxycarbonyl group, aryloxycarbonyl group, heterocyclic oxycarbonyl group, carbamoyl group, aliphatic sulfonyl group, arylsulfonyl group, heterocyclic sulfonyl group, aliphatic sulfonyloxy group, arylsulfonyloxy group, hetero Ring sulfonyloxy group, sulfamoyl group, aliphatic sulfonamide group, aryl sulfonamide group, heterocyclic sulfonamide group, amino group, aliphatic amino group, arylamino group, heterocyclic amino group, aliphatic oxycarbonylamino group, aryl Oxycarbonylamino group, heterocycle Xoxycarbonylamino group, aliphatic sulfinyl group, arylsulfinyl group, aliphatic thio group, arylthio group, hydroxy group, cyano group, sulfo group, carboxy group, aliphatic oxyamino group, aryloxyamino group, carbamoylamino group, sulfo group Examples include a famoylamino group, a halogen atom, a sulfamoylcarbamoyl group, a carbamoylsulfamoyl group, a dialiphatic oxyphosphinyl group, and a diaryloxyphosphinyl group.

<Azo pigment>
A pigment is a state in which molecules are firmly bonded to each other by cohesive energy due to strong interaction between dye molecules. In order to create this state, it is described in, for example, Journal of Imaging Society of Japan, Vol. 43, page 10 (2004) that van der Waals force between molecules and hydrogen bonding between molecules are necessary.
In order to increase the van der Waals force between molecules, introduction of an aromatic group, a polar group and / or a hetero atom into the molecule can be considered. Moreover, in order to form an intermolecular hydrogen bond, introduction | transduction of the substituent containing the hydrogen atom couple | bonded with the hetero atom to a molecule | numerator and / or introduction | transduction of an electron-donating ring-setting group etc. can be considered. Further, it is considered preferable that the polarity of the whole molecule is high. For this purpose, for example, a shorter chain group such as an alkyl group is preferable.

  From these viewpoints, the pigment molecule preferably contains an amide bond, a sulfonamide bond, an ether bond, a sulfone group, an oxycarbonyl group, an imide group, a hetero ring, a benzene ring and the like.

The azo pigment of the present invention is represented by the following general formula (1). By having a specific structure represented by the following general formula (1), it exhibits excellent characteristics in color characteristics such as tinting strength and hue, and also has excellent durability such as light resistance and ozone resistance. Can be shown.
The azo dye represented by the general formula (1) of the present invention will be described in detail below.

(In the general formula (1), R ₁ represents an aliphatic group, an aryl group or a heterocyclic group, R ₂ represents a hydrogen atom or an aliphatic group, R ₃ represents an aliphatic group, and R ₄ represents .X ₁ which represents an aliphatic group or an aryl group nitrogen atom, represents a C-R ₅ .R ₅ is a cyano group, a carbamoyl group, an aliphatic oxycarbonyl group, .R ₆ is hydrogen atom a carboxyl group or a sulfonyl group Or represents an aliphatic group.)

The aliphatic group represented by R ₁ is preferably an aliphatic group having 1 to 8 carbon atoms in total, may have a substituent, and may be saturated or unsaturated. The aliphatic group is preferably an aliphatic group having 1 to 4 carbon atoms in total, such as methyl, ethyl, vinyl, cyclohexyl, carbamoylmethyl and the like.
The aryl group represented by R ₁ is preferably an aryl group having 6 to 12 carbon atoms in total, may have a substituent, and is an aryl group having 6 to 10 carbon atoms in total. Are more preferable, and examples thereof include phenyl, 4-nitrophenyl, 4-acetylaminophenyl, 4-methanesulfonylphenyl, and the like.
The heterocyclic group represented by R ₁ is preferably a heterocyclic group bonded with 2 to 12 carbon atoms in total, may have a substituent, and may be saturated or unsaturated. It may be a condensed ring, preferably an unsaturated heterocycle, a 5- to 6-membered ring, which may be condensed, having 2 to 12 total carbon atoms, More preferably, it is an unsaturated 5- to 6-membered heterocycle having 2 to 10 total carbon atoms, such as 2-tetrafuranyl, 2-pyrimidinyl, 3-pyrimidinyl, 2-thiazolyl, 2-benzothiazolyl, 2-benzo Examples include oxazolyl, 2-pyridyl, 2-pyrazinyl, 3-imidazolyl, 2-benzimidazolyl and the like. As the group which may be substituted on the heterocyclic group of R ₁ , any group can be used as long as it can be substituted with the groups described in the above-mentioned substituent group, but preferably an aliphatic group, an aryl group, a hydroxy group Group, halogen atom, aliphatic oxy group, aliphatic thio group, optionally substituted amino group, carbamoylamino group, acylamino group, sulfonamido group, carbamoyl group, sulfamoyl group, etc., more preferably Group, aryl group, hydroxy group, aliphatic thio group, optionally substituted amino group, carbamoylamino group, acylamino group, and carbamoyl group.

The aliphatic group represented by R ₂ is preferably an aliphatic group having 1 to 8 carbon atoms in total, may have a substituent, and may be saturated or unsaturated. As the group that may be substituted with the aliphatic group of R ₂ , any group may be used as long as it is a group that can be substituted with the groups described in the above-mentioned substituent group. The aliphatic group of R ₂ is preferably an alkyl group having 1 to 8 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, such as methyl, ethyl, vinyl, cyclohexyl, carbamoylmethyl. Etc.

The aliphatic group represented by R ₃ is preferably an aliphatic group having 1 to 8 carbon atoms in total, may have a substituent, and may be saturated or unsaturated. As the group that may be substituted, any group may be used as long as it is a group that can be substituted with the groups described in the above-mentioned substituent group. The aliphatic group for R ₃ is preferably an alkyl group having 1 to 8 carbon atoms in total, more preferably an alkyl group having 1 to 6 carbon atoms in total, such as methyl, ethyl, i-propyl, cyclohexyl, t-butyl etc. are mentioned. This is the same as the aliphatic group described for R ₃ in the general formula (1).

The aliphatic group represented by R ₄ may have a substituent, may be saturated or unsaturated, and the group that may be substituted includes the above-mentioned substituent group. Any group can be used as long as it is a substitutable group. The aliphatic group for R ₄ is preferably an alkyl group having 1 to 16 carbon atoms in total, more preferably an alkyl group having 1 to 12 carbon atoms, such as methyl, ethyl, i-propyl, 2-acetylamino. And ethyl, 2-carbamoylaminoethyl and the like.
The aryl group represented by R ₄ may have a substituent, may be condensed, and may be substituted. Examples of the group that may be substituted include the groups described in the above-mentioned substituents section. Any group that can be substituted is acceptable. The aryl group represented by R ₄ preferably has a total carbon number of 6 to 16, more preferably a total carbon number of 6 to 12, such as phenyl, 4-acetylaminophenyl, 3-acetylamino. And phenyl, 4-carbamoylphenyl and the like.

The carbamoyl group represented by R ₅ is preferably an optionally substituted carbamoyl group, and the substituent is the group described in the above-mentioned substituent group, and a group that can be substituted on the carbamoyl group. Anything is fine. Examples of the optionally substituted carbamoyl group represented by R ₅ include an aliphatic carbamoyl group, an aromatic carbamoyl group, a heterocyclic carbamoyl group, and the like, preferably a carbamoyl group and an aliphatic carbamoyl group, and more An unsubstituted carbamoyl group is preferable.
The aliphatic oxycarbonyl group represented by R ₅ is preferably an aliphatic oxycarbonyl group having 1 to 8 carbon atoms in total, which may have a substituent, may be saturated, The group which may be saturated and may be substituted may be any group as long as it can be substituted with the groups described in the above-mentioned substituent group. The aliphatic oxycarbonyl group represented by R ₅ is preferably an alkoxycarbonyl group having 2 to 8 carbon atoms in total, and examples thereof include methoxycarbonyl and ethoxycarbonyl.
The sulfonyl group represented by R ₅ is preferably a sulfonyl group having 1 to 8 carbon atoms in total, including an aliphatic sulfonyl group and an arylsulfonyl group, and may further have a substituent. The sulfonyl group represented by R ₅ is preferably an alkylsulfonyl group having 1 to 8 carbon atoms in total, more preferably an alkylsulfonyl group having 1 to 4 carbon atoms in total, such as methanesulfonyl or ethane. Sulfonyl, butanesulfonyl and the like.

The aliphatic group represented by R ₆ is preferably an aliphatic group having 1 to 8 carbon atoms in total, may have a substituent, and may be saturated or unsaturated. The group which may be substituted with the aliphatic group of R ₆ may be any group as long as it is a group that can be substituted with the groups described in the above-mentioned substituent group. The aliphatic group represented by R ₆ is preferably an alkyl group having 1 to 8 carbon atoms in total, more preferably an alkyl group having 1 to 6 carbon atoms in total, for example, methyl, ethyl, vinyl, cyclohexyl , Isopropyl and the like.

In view of the effect of the present invention, R ₂ in the general formula (1) is preferably a hydrogen atom. From the viewpoint of the effect of the present invention, R ₃ in the general formula (1) is preferably a t-butyl group. In view of the effect of the present invention, R ₄ in the general formula (1) is preferably an aliphatic group. In view of the effect of the present invention, R ₅ in the general formula (1) is preferably a cyano group or an optionally substituted carbamoyl group. In view of the effects of the present invention, R ₆ is preferably a hydrogen atom.

  In view of the effect of the present invention, the dye represented by the general formula (1) is preferably a dye represented by the following general formula (2) or (3).

(In general formula (2) or (3), R ₁ , R ₂ , R ₃ and R ₄ have the same meaning as defined in general formula (1). R ₇ is a cyano group, carbamoyl group or aliphatic group. Represents an oxycarbonyl group.)

In terms of the effects of the present invention, the pigments represented by the general formulas (2) and (3) are such that R ₁ is a heterocycle, R ₂ is a hydrogen atom, and R ₃ is an aliphatic group. R ₄ is preferably an aliphatic group, and R 7 is preferably a cyano group or a carbamoyl group.
From the viewpoint of the effect of the present invention, among the general formulas (2) and (3), the pigment represented by the general formula (2) is preferable.

  Specific examples of the pigments represented by the general formulas (1) to (3) are shown below, but the pigments used in the present invention are not limited to the following examples.

Next, an example of the manufacturing method of the azo pigment represented by the general formulas (1) to (3) will be described. For example, a heterocyclic amine represented by the following general formula (4) is diazonium with non-aqueous acidity, a coupling reaction is performed with a compound represented by the following general formula (5) in an acidic state, and post-treatment by a conventional method is performed. To obtain a dye (intermediate compound). Furthermore, an azo pigment represented by the above general formula (1) can be produced from the obtained dye and R ¹ —X (X represents a leaving group).

(In the formula, R ₂ and X ₁ have the same meaning as defined in the general formula (1).)

(In the formula, R ₃ and R ₄ have the same meanings as defined in the general formula (1).)

  The reaction scheme is shown below.

(Wherein R _{1 to} R ₄ and X ₁ have the same meanings as defined in formulas (1) to (5). Preferred examples of X represent a halogen atom, alkylsulfonyl, arylsulfonyl, etc. Chlorine atom, bromine atom, methanesulfonyl, benzenesulfonyl, etc.)

Although some heterocyclic amines represented by the general formula (4) can be obtained as commercial products, they can be generally produced by known and commonly used methods. The heterocyclic coupler represented by the general formula (5) can be produced by the method described in JP-A-60-172982 and a method analogous thereto. The diazoniumation reaction of the heterocyclic amine represented by the general formula (4) is carried out, for example, in an acidic solvent such as sulfuric acid, phosphoric acid, and acetic acid with a reagent such as sodium nitrite, nitrosylsulfuric acid, isoamyl nitrite and the like at 15 ° C. or lower. The reaction can be carried out at a temperature for about 10 minutes to 6 hours. The coupling reaction is carried out by reacting the diazonium salt obtained by the above-described method with the compound represented by the general formula (5) at 40 ° C. or less, preferably 25 ° C. or less for about 10 minutes to 12 hours. Can do.
Some of the thus-reacted products have crystals precipitated, but generally, water or an alcohol solvent is added to the reaction solution, crystals are precipitated, filtered, and the general formula (1) ) To obtain an intermediate dye.
The azo pigment of the general formula (1) of the present invention is prepared by using the intermediate of the general formula (1) produced as described above as DMF (dimethylformamide), NMP (N-methylpyrrolidone), DMAc (dimethylacetamide), DMSO. A high boiling point organic solvent such as (dimethyl sulfoxide), a base such as potassium carbonate and sodium hydroxide, and the corresponding R ₁ —X are reacted at about 50 ° C. to 150 ° C. for about 30 minutes to 10 hours. When crystals are precipitated in the reaction solution, the precipitated crystals can be collected by filtration. In addition, an alcohol solvent, water or the like can be added to the reaction solution to precipitate crystals, and the precipitated crystals can be collected by filtration. The crystals collected by filtration can be washed and dried as necessary to obtain azo pigments represented by the general formulas (1) to (3).

  Organic pigments exist in a plurality of different crystalline forms, also called polymorphs. Crystal polymorphs have the same chemical composition but differ in the arrangement of building blocks (molecules or ions) in the crystal. The crystal structure determines the chemical and physical properties, and each polymorph can be distinguished by its rheology, color, and other color characteristics. Different polymorphs can also be confirmed by X-Ray Diffraction (powder X-ray diffraction measurement results) and X-Ray Analysis (X-ray crystal structure analysis results).

  As a tautomer of the compound represented by the general formula (1) in the present invention, there is a structure called a hydrazone form which is a tautomer of the azo group (—N═N—) part of the azo pigment structure. To do.

  The azo compound represented by the general formula (1) in the present invention includes, for example, at least one tautomer of the azo compound represented by the following general formula (1 ').

  In addition, in the present invention, when the compound represented by the general formula (1) has an acid group, a part or all of the acid group may be a salt type, and a salt type pigment and a free acid type The pigment may be mixed. Examples of the salt type include salts of alkali metals such as Na, Li and K, ammonium salts optionally substituted with an alkyl group or hydroxyalkyl group, and organic amine salts. Examples of organic amines include lower alkyl amines, hydroxy-substituted lower alkyl amines, carboxy-substituted lower alkyl amines, and polyamines having 2 to 10 alkyleneimine units having 2 to 4 carbon atoms in total. In the case of these salt types, the type is not limited to one type, and a plurality of types may be mixed.

  Further, in the structure of the pigment used in the present invention, when a plurality of acid groups are contained in one molecule, the plurality of acid groups may be salt type or acid type and may be different from each other.

<Pigment dispersion>
The pigment dispersion of the present invention is characterized by containing at least one azo pigment represented by the general formula (1). Thereby, it can be set as the pigment dispersion excellent in chromatic characteristics, durability, and dispersion stability.
When the compound represented by the general formula (1) is obtained as a crude product by the above production method, the crude product is obtained by purification such as recrystallization to obtain a high-purity product, or used as the pigment dispersion of the present invention. It is desirable to perform post-processing. Examples of post-processing methods include, for example, solvent particle milling process such as solvent salt milling, salt milling, dry milling, solvent milling, acid pasting, solvent heat treatment, etc., resin, surfactant and dispersant. The surface treatment process by etc. is mentioned.

  The compound represented by the general formula (1) of the present invention is preferably subjected to a solvent heating treatment as a post-treatment. Examples of the solvent used in the solvent heat treatment include water, aromatic hydrocarbon solvents such as toluene and xylene, halogenated hydrocarbon solvents such as chlorobenzene and o-dichlorobenzene, and alcohols such as isopropanol and isobutanol. Examples thereof include solvents, polar aprotic organic solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, glacial acetic acid, pyridine, and mixtures thereof. It is preferable to adjust the average particle diameter of the pigment to 0.01 μm to 1 μm by these post-treatments.

The pigment dispersion of the present invention may be aqueous or non-aqueous, but is preferably an aqueous pigment dispersion. As the aqueous liquid in which the pigment is dispersed in the aqueous pigment dispersion of the present invention, a mixture containing water as a main component and optionally adding a hydrophilic organic solvent can be used.
There is no restriction | limiting in particular about the content rate of the pigment in the pigment dispersion of this invention. For example, it can be 0.1-50 mass%.

  Examples of the hydrophilic organic solvent include methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, t-butanol, pentanol, hexanol, cyclohexanol, benzyl alcohol and other alcohols, ethylene glycol, diethylene glycol , Other alcohols such as triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol, ethylene glycol monomethyl ether, ethylene glycol mono Ethyl ether, ethylene glycol butyl ether, diethylene glycol mono Chill 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 monoethyl ether, ethylene glycol monophenyl ether Glycol derivatives such as ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenetriamine, triethylenetetramine, polyethyleneimine, tetramethylpropylenediamine Such as amine, 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 and the like.

  Furthermore, the aqueous pigment dispersion of the present invention may contain an aqueous resin. Examples of the aqueous resin include a water-soluble resin that dissolves in water, a water-dispersible resin that disperses in water, a colloidal dispersion resin, or a mixture thereof. Specific examples of the aqueous resin include acrylic, styrene-acrylic, polyester, polyamide, polyurethane, and fluorine resins.

  When the aqueous pigment dispersion in the present invention contains an aqueous resin, the content is not particularly limited. For example, it can be 0 to 100% by mass with respect to the pigment.

  In addition, surfactants and dispersants may be used to improve pigment dispersion and image quality. Examples of the surfactant include anionic, nonionic, cationic and amphoteric surfactants. Any surfactant may be used, but anionic or nonionic surfactants may be used. It is preferable to use it.

  When the water-based pigment dispersion in the present invention contains a surfactant, the content is not particularly limited. For example, it can be 0 to 100% by mass with respect to the pigment.

  Examples of anionic surfactants include fatty acid salts, alkyl sulfate esters, alkylbenzene sulfonates, alkyl naphthalene sulfonates, dialkyl sulfosuccinates, alkyl diaryl ether disulfonates, alkyl phosphates, and polyoxyethylene alkyls. Examples thereof include ether sulfate, polyoxyethylene alkylaryl ether sulfate, naphthalene sulfonic acid formalin condensate, polyoxyethylene alkyl phosphate ester salt, glycerol borate fatty acid ester, polyoxyethylene glycerol fatty acid ester and the like.

  Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, polyoxyethylene oxypropylene block copolymer, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, Examples include glycerin fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene alkylamine, fluorine-based, and silicon-based.

  The non-aqueous pigment dispersion of the present invention is obtained by dispersing the pigment represented by the general formula (4) in a non-aqueous vehicle. Resins used in non-aqueous vehicles are, for example, petroleum resins, casein, shellac, rosin modified maleic resin, rosin modified phenolic resin, nitrocellulose, cellulose acetate butyrate, cyclized rubber, chlorinated rubber, oxidized rubber, hydrochloric acid rubber , Phenolic resin, alkyd resin, polyester resin, unsaturated polyester resin, amino resin, epoxy resin, vinyl resin, vinyl chloride, vinyl chloride-vinyl acetate copolymer, acrylic resin, methacrylic resin, polyurethane resin, silicone resin, fluorine resin , Drying oil, synthetic drying oil, styrene / maleic acid resin, styrene / acrylic resin, polyamide resin, polyimide resin, benzoguanamine resin, melamine resin, urea resin chlorinated polypropylene, butyral resin, vinylidene chloride resin and the like. A photocurable resin may be used as the non-aqueous vehicle.

  Examples of the solvent used in the non-aqueous vehicle include aromatic solvents such as toluene, xylene, and methoxybenzene, and acetates such as ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, and propylene glycol monoethyl ether acetate. Solvents, propionate solvents such as ethoxyethyl propionate, alcohol solvents such as methanol and ethanol, ether solvents such as butyl cellosolve, propylene glycol monomethyl ether, diethylene glycol ethyl ether, diethylene glycol dimethyl ether, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc. Ketone solvents, aliphatic hydrocarbon solvents such as hexane, N, N-dimethylformamide, γ-butyrolactam, N Methyl-2-pyrrolidone, aniline, nitrogen compound-based solvent such as pyridine, a lactone-based solvents such as γ- butyrolactone, carbamic acid esters such as a mixture of 48:52 of methyl carbamate and ethyl carbamate acid.

  In the present invention, the volume average particle diameter of the pigment is preferably 10 nm or more and 250 nm or less. The volume average particle diameter of the pigment particles refers to the particle diameter of the pigment itself or the particle diameter to which the additive has adhered when an additive such as a dispersant is attached to the colorant. In the present invention, a Nanotrac UPA particle size analyzer (UPA-EX150; manufactured by Nikkiso Co., Ltd.) was used as a measuring device for the volume average particle diameter of the pigment. The measurement was performed according to a predetermined measuring method by placing 3 ml of the pigment dispersion in a measuring cell. As parameters to be input at the time of measurement, ink viscosity was used as the viscosity, and pigment density was used as the density of the dispersed particles.

  A more preferable volume average particle diameter is 20 nm or more and 250 nm or less, and further preferably 30 nm or more and 230 nm or less. When the number average particle size of the particles in the pigment dispersion is less than 10 nm, there are cases where the storage stability cannot be ensured, whereas when it exceeds 250 nm, the optical density may be lowered.

  The concentration of the pigment contained in the pigment dispersion of the present invention is preferably in the range of 1 to 35% by mass, and more preferably in the range of 2 to 25% by mass. If the density is less than 1% by mass, sufficient image density may not be obtained when the pigment dispersion is used alone as the ink. If the concentration exceeds 35% by mass, the dispersion stability may decrease.

  The pigment dispersion of the present invention can be obtained by dispersing the above azo pigment and an aqueous or non-aqueous medium using a dispersing device. Examples of the dispersing device that can be used include a ball mill, a sand mill, a bead mill, a roll mill, a jet mill, a paint shaker, an attritor, an ultrasonic disperser, and a disper.

The azo pigment of the present invention is used as a dye or pigment as a solid-state image pickup device such as a CCD or CMOS, a color filter for recording and reproducing a color image used in a display such as an LCD or PDP, or these color filters. Curable composition for producing a color image, a color image recording material for forming a color image, dyeing and the like. Specifically, color filters, curable compositions for producing these color filters, ink jet recording materials, heat sensitive recording materials, pressure sensitive recording materials, recording materials using electrophotographic methods, transfer type silver halide photosensitive materials , Printing ink, recording pen, fiber dyeing, hair dyeing, etc., preferably use for color filter preparation curable composition, ink jet recording material, heat sensitive recording material, electrophotographic recording material, etc. It is done.
The pigment of the present invention is used by optimizing the physical properties such as solubility and dispersibility suitable for the application by adjusting the substituents. The pigment of the present invention can also be used in a dissolved state, an emulsified dispersion state, or a solid dispersion state depending on the system used.

  EXAMPLES The present invention will be specifically described below based on examples, but the present invention is not limited to these examples. In the examples, parts are based on mass.

Synthesis example 1
Synthesis of Specific Compound Example D-1 Specific compound example D-1 was synthesized by the following route.

Synthesis of (3) 1.8 g of compound (1) was added to 20 ml of phosphoric acid and heated to 30 ° C. to dissolve. This solution was ice-cooled and kept at −5 to 0 ° C., 1.2 g of sodium nitrite was added and stirred for 1 hour to obtain a diazonium salt solution. Separately, 5.5 g of compound (2) was suspended in 50 ml of methanol, and the above diazonium salt solution was added thereto at 8 ° C. or lower. Upon completion of the addition, the ice bath was removed, and the mixture was stirred for 2 hours to precipitate crystals. 50 ml of methanol was further added to the reaction solution, and the mixture was further stirred for 1 hour. The precipitated crystals were separated by filtration, washed with 30 ml of methanol, and further thoroughly washed with water. The crystals were dried to obtain 6.0 g of compound (3). Yield 79.0%.

Synthesis of D-1 To 2.5 g of the compound (3) were added 20 parts of dimethylacetamide, 2.5 g of potassium carbonate, and 1.1 g of 2-chloropyrimidine, and the mixture was stirred at 100 ° C. for 3 hours. The reaction solution was returned to room temperature, 100 ml of methanol was added, and the mixture was stirred at room temperature for 1 hour. The precipitated crystals were separated by filtration and washed with methanol. The obtained crystals were added to 100 ml of water and 2 ml of acetic acid without drying, and stirred at room temperature for 30 minutes. The crystals were separated by filtration and sufficiently washed with water. The obtained crystals were added to 100 ml of methanol without drying and heated to reflux. Thereafter, the mixture was stirred for 2 hours under air cooling, and the precipitated crystals were separated by filtration and washed with 50 ml of methanol. The crystals were dried to obtain 2.2 g of the compound D-1 of the present invention. Yield 75.9% λmax: 455 nm ε: 3.72 × 10 ⁴ (DMF). FIG. 1 shows an infrared absorption chart.

Synthesis example 2
Synthesis of Specific Compound Example D-3 Specific compound example D-3 was synthesized by the following route.

Synthesis of (5) 1.4 g of compound (4) was added to 15 ml of phosphoric acid and dissolved by heating to 40 ° C. This solution was ice-cooled and kept at -5 to 0 ° C., 1.2 g of sodium nitrite was added and stirred for 1 hour to obtain a diazonium salt solution. Separately, 5.9 g of compound (2) was added to the above diazonium salt solution at 20 ° C. or lower and stirred for 30 minutes. Further, the ice bath was removed and the mixture was stirred for 2 hours. The reaction solution was cooled again, 200 ml of water was added at 15 to 25 ° C., and the mixture was further stirred at 20 to 25 ° C. for 1 hour. The precipitated crystals were separated by filtration and washed with 50 ml of methanol. The crystals were dried to obtain 5.6 g of compound (5). Yield 77.7%.

Synthesis of Specific Compound Example D-3 20 ml of dimethylacetamide, 2.0 g of potassium carbonate and 1.0 g of 2-chlorobenzothiazole were added to 2.2 g of the compound (5), and the mixture was stirred at 90 ° C. for 5 hours. The reaction solution was returned to room temperature, 100 ml of water and 2 ml of acetic acid were added, and the mixture was stirred at room temperature for 1 hour. The precipitated crystals were separated by filtration and washed with water. The obtained crystals were added to 50 ml of methanol without drying and stirred at 70 ° C. for 1 hour. Thereafter, the mixture was stirred for 2 hours under air cooling, and the precipitated crystals were separated by filtration and washed with 50 ml of methanol. The crystals were dried to obtain 1.8 g of the compound D-3 of the present invention. Yield 62.1% λmax: 454 nm ε: 4.43 × 10 ⁴ (DMF). FIG. 2 shows an infrared absorption chart.

Synthesis example 3
Synthesis of Specific Compound Example D-6 Specific compound example D-6 was synthesized by the following route.

Synthesis of Specific Compound D-6 20 parts of dimethylacetamide, 2.0 g of potassium carbonate, and 0.9 g of 2-chlorobenzothiazole were added to 2.2 g of the compound (3), and the mixture was stirred at 100 ° C. for 5 hours. The reaction solution was returned to room temperature, 100 ml of methanol was added, and the mixture was stirred at room temperature for 1 hour. The precipitated crystals were separated by filtration and washed with methanol. The obtained crystals were added to 100 ml of water and 2 ml of acetic acid without drying, and stirred at room temperature for 30 minutes. The crystals were separated by filtration and sufficiently washed with water. The obtained crystals were added to 100 ml of methanol without drying and heated to reflux. Thereafter, the mixture was stirred for 2 hours under air cooling, and the precipitated crystals were separated by filtration and washed with 50 ml of methanol. The crystals were dried to obtain 2.0 g of Compound D-6 of the present invention. Yield 70.4% λmax: 464 nm ε: 5.02 × 10 ⁴ (DMF). FIG. 3 shows an infrared absorption chart.

Synthesis example 4
Synthesis of Specific Compound Example D-22 Specific Compound Example D-22 was synthesized by the following route.

Synthesis of Compound (7) 4.2 parts of Compound (1) was added to 50 parts of phosphoric acid and heated to 60 ° C. to dissolve. This solution was ice-cooled, maintained at -5 to 0 ° C, 2.9 parts of sodium nitrite was added, and the mixture was stirred for 1 hour to obtain a diazonium salt solution. Separately, 5 parts of compound (6) was prepared by dissolving in 300 parts of methanol, and the above diazonium salt solution was added thereto at 0 ° C. or less. After stirring for 1 hour, the ice bath was removed and the mixture was stirred at room temperature for 1 hour. The precipitated crystals were separated by filtration, washed with 300 parts of methanol, and further thoroughly washed with water. The crystals were dried to obtain 7.6 parts of compound (7). Yield 80.9%.

Synthesis of Specific Compound D-22 To 3.4 parts of Compound (7) were added 100 parts of dimethylacetamide, 3.7 parts of potassium carbonate, and 6.1 parts of 2-chlorobenzothiazole, and the mixture was stirred at 100 ° C. for 3 hours. The reaction solution was returned to room temperature, 200 parts of methanol and 3 parts of acetic acid were added, and the mixture was stirred at room temperature for 1 hour. The precipitated crystals were separated by filtration, washed with methanol, and further thoroughly washed with water. The obtained crystals were added to 20 parts of methanol and 10 parts of water without drying, and stirred at 65 ° C. for 3 hours. Thereafter, the mixture was stirred for 1 hour under air cooling, and the precipitated crystals were separated by filtration and washed with 30 parts of methanol. The crystals were dried to obtain 1.2 parts of a specific compound (D-22) of the present invention. Yield 55.6%, λmax: 442 nm ε: 3.89 × 10 ⁴ (DMF). FIG. 4 shows an infrared absorption chart.

Synthesis example 5
Synthesis of Specific Compound Example D-23 Specific Compound Example D-23 was synthesized by the following route.

Synthesis of Compound (8) 4.6 parts of Compound (4) was added to 55 parts of phosphoric acid and heated to 60 ° C. to dissolve. This solution was ice-cooled and maintained at -5 to 0 ° C, and 4.2 parts of sodium nitrite was added and stirred for 1 hour to obtain a diazonium salt solution. Separately, 7.1 parts of compound (6) was dissolved in 300 parts of methanol, and the above-described diazonium salt solution was added thereto at 0 ° C. or lower. After stirring for 1 hour, the ice bath was removed and the mixture was stirred at room temperature for 1 hour. The precipitated crystals were separated by filtration, washed with 300 parts of methanol, and further thoroughly washed with water. The crystals were dried to obtain 9.4 parts of compound (8). Yield 88.7%.

Synthesis of Specific Compound D-23 To 8.2 parts of (8), 160 parts of dimethylacetamide, 7.4 parts of potassium carbonate, and 13.2 parts of 2-chlorobenzothiazole were added and stirred at 100 ° C. for 3 hours. The reaction solution was returned to room temperature, 7 parts of acetic acid, 100 parts of methanol and 200 parts of water were added and stirred at room temperature for 1 hour. The precipitated crystals were separated by filtration, washed with methanol, and further thoroughly washed with water. The obtained crystals were added to 160 parts of methanol and 80 parts of water without drying, and stirred at 65 ° C. for 3 hours. Thereafter, the mixture was stirred for 1 hour under air cooling, and the precipitated crystals were separated by filtration and washed with 300 parts of methanol. The crystals were dried to obtain 6.0 parts of a specific compound (D-23) of the present invention. Yield 46.7%, λmax: 452 nm, ε: 3.46 × 10 ⁴ (DMF). FIG. 5 shows an infrared absorption chart.

[Example 1]
Specific Example Compound D-1 pigment 2.5 parts, sodium oleate 0.5 part, glycerin 5 parts, water 42 parts are mixed, and each 100 parts of zirconia beads having a diameter of 0.1 mm are used with a planetary ball mill. Dispersion was performed at 300 rpm for 6 hours. After the dispersion, the zirconia beads were separated to obtain a yellow pigment dispersion.

[Comparative Example 1]
In place of the pigment of Example 1, C.I. I. A yellow pigment dispersion was obtained in the same manner as in Example 1 except that CI Pigment Yellow 128 (CROMOPHTAL YELLOW 8GN manufactured by Ciba Specialty) was used.

(Evaluation)
<Dispersion stability>
The pigment dispersion obtained above was measured for volume average particle size by a conventional method using a dynamic light scattering particle size measuring device (Nikkiso Microtrack UPA150). The volume average particle diameter measured after 2 hours from the preparation of the pigment dispersion and the volume average particle diameter after storage at 70 ° C. for 2 days are both 230 nm or less, and either one is 231 nm or more. did. The results are shown in Table 1.
<Evaluation of coloring power>
The pigment dispersions obtained in the above Examples and Comparative Examples were No. 3 was applied to art paper using a bar coater. The image density of the obtained coated material was measured using a reflection densitometer (X-Rite 938 manufactured by X-Rite). The results are shown in Table 1.
<Hue evaluation>
The hue was evaluated using a reflection spectrum at an image density of 1.0 of a coated material produced in the same manner as in the above <Coloring power evaluation>. Evaluation is performed with ○ (good) when the reflectance at 580 nm is 75% or more and 15% or less at 430 nm and the reflectance at 500 nm is 30% to 60%, and × (defect) is not within the standard. It was. The results are shown in Table 1.
<Light resistance evaluation>
The coated material having an image density of 1.0 used for the hue evaluation was irradiated with xenon light (160000 lux) for 7 days using a fade meter, and the image density before and after the xenon irradiation was measured using a reflection densitometer, and the dye residual ratio [(Concentration after irradiation / Concentration before irradiation) × 100%] The results are shown in Table 1.

[Examples 2 to 4]
A pigment dispersion was prepared in the same manner except that the specific compound example D-1 of Example 1 was changed as shown in Table 1, and the same evaluation was performed.

  As is apparent from the results in Table 1, the pigment dispersion of the present invention is excellent in color tone and exhibits high coloring power and light resistance. Therefore, the pigment dispersion of the present invention includes, for example, printing inks such as inkjet, color toners for electrophotography, displays such as LCDs and PDPs, color filters used in image sensors such as CCDs, paints, colored plastics, and the like. Can be suitably used.

It is a figure of the infrared absorption spectrum of the specific compound example D-1 synthesize | combined according to the synthesis example 1. FIG. It is a figure of the infrared absorption spectrum of specific compound example D-3 synthesize | combined according to the synthesis example 2. FIG. It is a figure of the infrared absorption spectrum of specific compound example D-6 synthesize | combined according to the synthesis example 3. FIG. It is a figure of the infrared absorption spectrum of specific compound example D-22 synthesize | combined according to the synthesis example 4. FIG. It is a figure of the infrared absorption spectrum of specific compound example D-23 synthesize | combined according to the synthesis example 5. FIG.

Claims (3)

An azo pigment represented by the following general formula (1), a salt, a hydrate, and a tautomer thereof.

(In the general formula (1), R ₁ represents an aliphatic group, an aryl group or a heterocyclic group, R ₂ represents a hydrogen atom or an aliphatic group, R ₃ represents an aliphatic group, and R ₄ represents .X ₁ which represents an aliphatic group or an aryl group nitrogen atom, represents a C-R ₅ .R ₅ is a cyano group, a carbamoyl group, an aliphatic oxycarbonyl group, .R ₆ is hydrogen atom a carboxyl group or a sulfonyl group Or represents an aliphatic group.) The azo pigment represented by the general formula (1) is represented by the following general formula (2) or (3), the azo pigment according to claim 1, a salt thereof, a hydrate, and a mixture thereof. Mutant body.

(In General Formula (2), R ₁ represents an aliphatic group, an aryl group, or a heterocyclic group, R ₂ represents a hydrogen atom or an aliphatic group, R ₃ represents an aliphatic group, and R ₄ represents Represents an aliphatic group or an aryl group, and R ₇ represents a cyano group, a carbamoyl group or an aliphatic oxycarbonyl group.   A pigment dispersion comprising at least one of the azo pigment according to claim 1 or 2, a salt, a hydrate, and a tautomer thereof.

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