JP2013076012A - Azo dye, and coloring composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an azo dye and a coloring composition, excellent in solubility to non-polar solvents, particularly hydrocarbon-based solvents.SOLUTION: The azo dye is represented by formula (1), and has a solubility to n-hexane at 25°C and at 0.1 MPa of ≥1 mass%. In the formula (1), A is a residue of a 5-membered heterocyclic diazo component A-NH2; Band Bare each independently -CR=, -CR= or a nitrogen atom, wherein Band Bare not simultaneously a nitrogen atom; Rand Rare each independently a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group or the like; G, Rand Rare each independently a hydrogen atom, a halogen atom, an aliphatic group, a heterocyclic group or the like; Ror Rand R, and Rand Rwhich Bor Bhas each independently may bond mutually to form a 5- or 6-membered ring.

Description

  The present invention relates to an azo dye and a coloring composition.

In recent years, many organic dyes have been used in display materials, optical recording media, ink jet materials and the like. When a dye is used in a coating process or an inkjet process, high solubility in a solvent is required in addition to a high molar extinction coefficient in order to increase coloring efficiency.
In addition, since non-patent literature 1 reports an electrowetting display, an electrowetting display has attracted attention. In the electrowetting display, a plurality of pixels filled with two phases of an aqueous medium and an oil-colored ink are arranged on a substrate, and the affinity of the aqueous medium / oil-colored ink interface is applied to each pixel by on-off of voltage application. This is an image display method in which the property is controlled and the oil-based colored ink is developed / aggregated on the substrate. A dye used for such an electrowetting display is required to have high solubility in a hydrocarbon solvent.

  As a color filter dye as a display member, for example, various azo dye compounds including the following compounds C-101 and C-102 are known.

Nature (London), 425, 383 (2003)

However, the dyes such as C-101 and C-102 are insufficient in terms of solubility in nonpolar solvents, particularly solubility in hydrocarbon solvents, and further improvement has been demanded.
An object of the present invention is to provide an azo dye having excellent solubility in a nonpolar solvent, particularly a hydrocarbon solvent. It is another object of the present invention to provide a coloring composition suitable for a display device that contains the azo dye and operates on the principle of the electrowetting method and a color filter of the display device that operates on the electrophoresis method.

<1> An azo dye represented by the following general formula (1) and having a solubility in n-hexane at 25 ° C. and 0.1 MPa of 1% by mass or more.

A represents a residue of a 5-membered heterocyclic diazo component A-NH _2. B ¹ and ^{B 2} are each ^{independently, -CR 1 =, - CR 2} =, or a nitrogen atom, ^{B 1} and ^{B 2} do not simultaneously represent a nitrogen atom. R ⁵ and R ⁶ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkylsulfonyl group, arylsulfonyl group, or Represents a sulfamoyl group. G, R ¹ and R ² are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, acyl group, Substitution substituted with hydroxyl group, alkoxy group, aryloxy group, silyloxy group, acyloxy group, carbamoyloxy group, heterocyclic oxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, alkyl group or aryl group or heterocyclic group Amino group, acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkylsulfonylamino group, arylsulfonylamino group, aryloxycarbonylamino group, nitro group, alkylthio group, ant Thio group, an alkylsulfonyl group, an arylsulfonyl group, an alkylsulfinyl group, an arylsulfinyl group, a sulfamoyl group, a sulfo group, or a heterocyclic thio group. R ¹ or R ² and R ⁵ , and R ⁵ and R ⁶ of B ¹ or B ² may be independently bonded to each other to form a 5-membered or 6-membered ring.

<2> The azo dye according to <1>, wherein the azo dye represented by the general formula (1) is a compound represented by the following general formula (2).

Z ¹ represents an electron-withdrawing group having a Hammett's substituent constant σp value of 0.20 or more, and Z ² represents a hydrogen atom, an aliphatic group, an aromatic group, or a heterocyclic group. R ¹ and R ² are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, acyl group, hydroxyl group , Substituted amino groups substituted by alkoxy groups, aryloxy groups, silyloxy groups, acyloxy groups, carbamoyloxy groups, heterocyclic oxy groups, alkoxycarbonyloxy groups, aryloxycarbonyloxy groups, alkyl groups or aryl groups or heterocyclic groups , Acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkylsulfonylamino group, arylsulfonylamino group, aryloxycarbonylamino group, nitro group, alkylthio group, aryl O group, an alkylsulfonyl group, an arylsulfonyl group, an alkylsulfinyl group, an arylsulfinyl group, a sulfamoyl group, a sulfo group, or a heterocyclic thio group. R ³ and R ⁴ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkylsulfonyl group, arylsulfonyl group, or sulfamoyl. Represents a group. R ⁵ and R ⁶ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkylsulfonyl group, arylsulfonyl group, or Represents a sulfamoyl group. R ¹ and R ⁵ , and R ⁵ and R ⁶ may be independently bonded to each other to form a 5-membered or 6-membered ring. Q represents a hydrogen atom, an aliphatic group, an aromatic group, or a heterocyclic group.

<3> A coloring composition comprising the azo dye according to <1> or <2> and a nonpolar solvent, which is used for producing a color filter of a display device that operates on the principle of an electrowetting method.
<4> A colored composition comprising the azo dye according to <1> or <2> and a nonpolar solvent and used for producing a color filter of a display device operating by electrophoresis.

In the present invention, the azo dye represented by the general formula (1) is a dye having no polar group such as —SO ₃ H, —PO ₃ H ₂ , and —CO ₂ H in the molecule. It can be easily dissolved in a polar solvent, and can be dissolved in a nonpolar solvent to prepare a dye composition.
In particular, since the azo dye represented by the general formula (1) has a long-chain alkyl group and a branched alkyl group, it has excellent solubility in a nonpolar solvent. Since the SP value (solubility parameter) of the azo dye represented by the general formula (1) is close to the SP value of the nonpolar solvent used in the present invention, the solubility with the nonpolar solvent is improved. Estimated. The SP values of C-101 and C-102 are considered to have a decrease in solubility because a polar group is introduced and the SP value is different from the SP value of the nonpolar solvent.

  According to the present invention, an azo dye excellent in solubility in a nonpolar solvent, particularly a hydrocarbon solvent can be provided. Further, according to the present invention, it is possible to provide a coloring composition suitable for a color filter of a display device that includes the azo dye and operates on the principle of electrowetting method, and a display device that operates on an electrophoresis method. Yes.

<Azo dye>
The azo dye represented by the following general formula (1) of the present invention has a solubility in n-hexane of 1% by mass or more at 25 ° C. and 0.1 MPa.
As a dye, the solubility in n-hexane at 25 ° C. and 0.1 MPa is 1% by mass or more, and by using an azo dye represented by the general formula (1), a display etc. It is useful as a dye used for a display that operates in principle or a display that operates by electrophoresis.
Hereinafter, the azo dye represented by the general formula (1) will be described in detail.

A represents a residue of a 5-membered heterocyclic diazo component A-NH _2. B ¹ and ^{B 2} are each ^{independently, -CR 1 =, - CR 2} =, or a nitrogen atom, ^{B 1} and ^{B 2} do not simultaneously represent a nitrogen atom. R ⁵ and R ⁶ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkylsulfonyl group, arylsulfonyl group, or Represents a sulfamoyl group. G, R ¹ and R ² are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, acyl group, Substitution substituted with hydroxyl group, alkoxy group, aryloxy group, silyloxy group, acyloxy group, carbamoyloxy group, heterocyclic oxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, alkyl group or aryl group or heterocyclic group Amino group, acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkylsulfonylamino group, arylsulfonylamino group, aryloxycarbonylamino group, nitro group, alkylthio group, ant Thio group, an alkylsulfonyl group, an arylsulfonyl group, an alkylsulfinyl group, an arylsulfinyl group, sulfamoyl group, sulfo group or a heterocyclic thio group,. R ¹ or R ² and R ⁵ , and R ⁵ and R ⁶ of B ¹ or B ² may be independently bonded to each other to form a 5-membered or 6-membered ring.

In Formula (1), A represents the residue of A-NH ₂ is a 5-membered heterocyclic diazo component. Examples of heteroatoms 5-membered heterocyclic ring constituting A of this A-NH _2, can be mentioned N, O, and S. A nitrogen-containing 5-membered heterocyclic ring is preferable, and an aliphatic ring, an aromatic ring or another heterocyclic ring may be condensed to the heterocyclic ring.

  Preferable examples of the heterocyclic ring in A include a pyrazole ring, an imidazole ring, a thiazole ring, an isothiazole ring, a thiadiazole ring, a benzothiazole ring, a benzoxazole ring, and a benzoisothiazole ring. Each of these heterocycles may further have a substituent. Among these, a pyrazole ring, an imidazole ring, an isothiazole ring, a thiadiazole ring, and a benzothiazole ring represented by the following general formulas (a) to (f) are preferable.

R ^{7 to} R ²⁰ in the general formulas (a) to (f) have the same meanings as G, R ¹ , and R ² in the general formula (1), and preferred embodiments thereof are also the same. Of the general formulas (a) to (f), preferred are the pyrazole ring and isothiazole ring represented by the general formula (a) or (b), and the most preferred is represented by the general formula (a). It is a pyrazole ring.

Wherein ^{B 1} and ^{B 2} are each ^{independently, -CR 1 =, - CR 2} =, or a nitrogen atom, ^{B 1} and ^{B 2} do not simultaneously represent a nitrogen atom. ^That, -CR 1 =, - or represents a CR ² =, or either one of ^{B 1} and ^{B 2} is a nitrogen atom, the other represents -CR ¹ = or -CR ² =. Among them, particularly preferred are those each representing -CR ¹ = and -CR ² =. R ^1, and ^{R 2, R 1} in the general formula (1), and ^{R 2} in the above formula, the same applies to its preferred embodiments.

R ⁵ and R ⁶ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkylsulfonyl group, arylsulfonyl group, Alternatively, it represents a sulfamoyl group, and each group may further have a substituent. Preferred groups represented by R ⁵ and R ⁶ include a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, an acyl group, an alkylsulfonyl group, or an arylsulfonyl group, and more preferably a hydrogen atom. An aromatic group, a heterocyclic group, an acyl group, an alkylsulfonyl group, or an arylsulfonyl group. Most preferably, they are a hydrogen atom, an aromatic group, and a heterocyclic group. An embodiment in which each of these preferable groups further has a substituent is also suitable.

G, R ¹ and R ² are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, acyl group , Hydroxyl group, alkoxy group, aryloxy group, silyloxy group, acyloxy group, carbamoyloxy group, heterocyclic oxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, “substituted by alkyl group, aryl group or heterocyclic group Substituted amino group ", acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkylsulfonylamino group, arylsulfonylamino group, aryloxycarbonylamino group, nitro group, alkylthio group , Riruchio group, an alkylsulfonyl group, an arylsulfonyl group, an alkylsulfinyl group, an arylsulfinyl group, a sulfamoyl group, a sulfo group or a heterocyclic thio group, and these groups may be further substituted.

  Preferred groups represented by G include hydrogen atom, halogen atom, aliphatic group, aromatic group, hydroxyl group, alkoxy group, aryloxy group, acyloxy group, heterocyclic oxy group, “alkyl group, aryl group or A substituted amino group substituted with a heterocyclic group '', an acylamino group, a ureido group, a sulfamoylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, an alkylthio group, an arylthio group, or a heterocyclic thio group, More preferred are a hydrogen atom, a halogen atom, an alkyl group, a hydroxyl group, an alkoxy group, an aryloxy group, an acyloxy group, a “substituted amino group substituted with an alkyl group, an aryl group or a heterocyclic group”, or an acylamino group. Of these, a hydrogen atom and an arylamino group are most preferable. Each group may further have a substituent.

Preferable groups represented by R ¹ and R ² include a hydrogen atom, an aliphatic group, an alkoxycarbonyl group, a carbamoyl group, or a cyano group. Each group may further have a substituent.
Further, R ¹ or R ² and R ⁵ and / or R ⁵ and R ⁶ of B ¹ or B ² may be bonded to each other to form a 5-membered ring or a 6-membered ring.
Examples of the substituent in the case where each group represented by A, R ¹ , R ² , R ⁵ , R ⁶ , and G further has a substituent include those listed for G, R ¹ , and R ² above And the same substituents that do not have a polar group.

Hereinafter, each group which concerns on General formula (1) is demonstrated in detail.
In the present specification, 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 part of the aralkyl group and the substituted aralkyl group is preferably phenyl or naphthyl, particularly preferably phenyl. Examples of aliphatic groups are methyl, ethyl, butyl, isopropyl, t-butyl, normal octyl, 2-ethylhexyl, normaldecyl, normaldodecyl, 3,5,5-trimethylhexyl. Groups, hydroxyethyl groups, methoxyethyl groups, cyanoethyl groups, trifluoromethyl groups, cyclohexyl groups, benzyl groups, 2-phenethyl groups, vinyl groups, and allyl groups.

  In the present specification, the aromatic group means an aryl group and a substituted aryl group. The aryl group is preferably a phenyl group or a naphthyl group, and particularly preferably a phenyl group. The aromatic group preferably has 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms. Examples of the aromatic group include phenyl group, p-tolyl group, p-methoxyphenyl group, o-chlorophenyl, 2,4,6-trimethylphenyl group, and 2,6-diethyl-4-methylphenyl group. .

  In the present specification, 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. The heterocyclic group is preferably a 5-membered or 6-membered heterocyclic group. Examples of the substituent include aliphatic groups, halogen atoms, alkyl and arylsulfonyl groups, acyl groups, acylamino groups, sulfamoyl groups, carbamoyl groups, and the like. Examples of the heterocyclic group include 2-pyridyl group, 2-thienyl group, 2-thiazolyl group, 2-benzothiazolyl group, 2-benzoxazolyl 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, a dimethylcarbamoyl group, a dibutylcarbamoyl group, a dioctylcarbamoyl group, and a pyrrolidinocarbonyl 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 12 carbon atoms is preferable. Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, a butoxycarbonyl group, an octyloxycarbonyl group, and a dodecyloxycarbonyl 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 12 carbon atoms is preferable. Examples of the aryloxycarbonyl group include a phenoxycarbonyl group.

The acyl group includes an acyl group having a substituent and an unsubstituted acyl group. As the acyl group, an acyl group having 1 to 12 carbon atoms is preferable. Examples of the acyl group include an acetyl group, an octanoyl group, a 2-ethylhexanoyl group, a dodecanoyl 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-C12 alkoxy group is preferable. Examples of the substituent include an alkoxy group and a hydroxyl group. Examples of alkoxy groups include methoxy, ethoxy, isopropoxy, butoxy, octyloxy, 2-ethylhexyloxy, 3,5,5-trimethylhexyloxy, decyloxy, dodecyloxy, methoxyethoxy Groups, hydroxyethoxy groups.
The aryloxy group includes an aryloxy group having a substituent and an unsubstituted aryloxy group. As the aryloxy group, an aryloxy group having 6 to 12 carbon atoms is preferable. Examples of the substituent include an alkoxy group. Examples of the aryloxy group include a phenoxy group, a p-methoxyphenoxy group, an o-methoxyphenoxy group, a p-octyloxyphenoxy group, and a p-dodecyloxyphenoxy group.

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 12 carbon atoms is preferable. Examples of the acyloxy group include an acetoxy group, an octanoyloxy group, a 2-ethylhexanoyloxy group, a dodecanoyloxy 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 heterocyclic oxy group is preferably an oxy group having a 5-membered or 6-membered heterocyclic group. Examples of the heterocyclic group include 2-pyridyl group, 2-thienyl group, 2-thiazolyl group, 2 -Benzothiazolyl group, 2-benzoxazolyl group and 2-furyl group.
The alkoxycarbonyloxy group is preferably an alkoxycarbonyloxy group having a substituent or an unsubstituted alkoxycarbonyloxy group, and the alkoxycarbonyloxy group is preferably an alkoxycarbonyloxy group having 2 to 12 carbon atoms. Examples of the alkoxycarbonyloxy group include a methoxycarbonyloxy group, an ethoxycarbonyloxy group, a butoxycarbonyloxy group, an octyloxycarbonyloxy group, and a dodecyloxycarbonyloxy group.
The aryloxycarbonyloxy group includes an aryloxycarbonyloxy group having a substituent and an unsubstituted aryloxycarbonyloxy group. As the aryloxycarbonyloxy group, an aryloxycarbonyloxy group having 7 to 12 carbon atoms is preferable. Examples of the aryloxycarbonyloxy group include a phenoxycarbonyloxy group.

The substituent of the “substituted amino group substituted with an alkyl group, aryl group or heterocyclic group” may further have a substituent. Unsubstituted amino groups are not included. As an alkylamino group, a C1-C6 alkylamino group is preferable. Examples of the alkylamino group include a methylamino group, a diethylamino group, a dibutylamino group, a dihexylamino group, and a dioctylamino group. The arylamino group includes an arylamino group having a substituent and an unsubstituted arylamino group. As the arylamino group, an arylamino group having 6 to 12 carbon atoms is preferable. Furthermore, examples of the substituent when having a substituent include a halogen atom and an alkyl group. Examples of arylamino groups include anilino group, 2-methylanilino group, 2,4,6-trimethylanilino group, 2,6-diethyl-4-methylanilino group, 2-chloroanilino group, 2,4,6-trichloro Anilino group is included.
The acylamino group includes an acylamino group having a substituent. The acylamino group is preferably an acylamino group having 2 to 12 carbon atoms. Examples of the acylamino group include an acetylamino group, a propionylamino group, a benzoylamino group, and an N-phenylacetylamino 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 12 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 an N, N-dipropylsulfamoylamino group and an N, N-dibutylsulfamoylamino group.
The alkoxycarbonylamino group includes an alkoxycarbonylamino group having a substituent and an unsubstituted alkoxycarbonylamino group. The alkoxycarbonylamino group is preferably an alkoxycarbonylamino group having 2 to 12 carbon atoms. Examples of the alkoxycarbonylamino group include an ethoxycarbonylamino group.
The aryloxycarbonylamino group includes an aryloxycarbonylamino group having a substituent and an unsubstituted aryloxycarbonylamino group. As the aryloxycarbonylamino group, an aryloxycarbonylamino group having 7 to 12 carbon atoms is preferable. Examples of the aryloxycarbonylamino group include a phenoxycarbonylamino group.

The alkylsulfonylamino group and arylsulfonylamino group include a substituted alkyl and arylsulfonylamino group, and an unsubstituted alkyl and arylsulfonylamino group. As the sulfonylamino group, a sulfonylamino group having 1 to 12 carbon atoms is preferable. Examples of the sulfonylamino group include a methanesulfonylamino group, an N-phenylmethanesulfonylamino group, an octanesulfonylamino group, a dodecanesulfonylamino group, and a benzenesulfonylamino group.
The alkylthio group, arylthio group and heterocyclic thio group include an alkylthio group having a substituent, an arylthio group and a heterocyclic thio group and an unsubstituted alkylthio group, an arylthio group and a heterocyclic thio group. As the alkylthio group, arylthio group and heterocyclic thio group, those having 1 to 12 carbon atoms are preferred. Examples of the alkyl, aryl or heterocyclic thio group include a methylthio group, an octylthio group, a dodecylthio group, a phenylthio group and a 2-pyridylthio group.

Examples of the alkylsulfonyl group and the arylsulfonyl group include a methanesulfonyl group and a phenylsulfonyl group, respectively.
Examples of the alkylsulfinyl group and the arylsulfinyl group include a methanesulfinyl group and a 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.

  In the present invention, the azo dye represented by the general formula (1) is particularly preferably an azo dye represented by the following general formula (2).

In the general formula (2), Z ¹ represents an electron-withdrawing group having a Hammett's substituent constant σp value of 0.20 or more.
Z ¹ is preferably an electron-withdrawing group having a σp value of 0.30 to 1.0. Preferred examples of the specific group include an electron-withdrawing substituent described later. Among them, an acyl group having 2 to 12 carbon atoms, an alkyloxycarbonyl group having 2 to 12 carbon atoms, a nitro group, a cyano group, and 1 to 1 carbon atoms. Twelve alkylsulfonyl groups, C6-C18 arylsulfonyl groups, C1-C12 carbamoyl groups, or C1-C12 halogenated alkyl groups are preferable. Particularly preferred are a cyano group, an alkylsulfonyl group having 1 to 12 carbon atoms, and an arylsulfonyl group having 6 to 18 carbon atoms, and most preferred is a cyano group.

Z ² represents a hydrogen atom, an aliphatic group, an aromatic group, or a heterocyclic group, and the aliphatic group, the aromatic group, and the heterocyclic group are as described above.
In general ^R 1 in formula (2) ^in, R 2, ^{R 5,} and ^{R 6, R 1,} R 2, ^{R 5} in the general formula described above (1), and has the same meaning as ^{R 6,} preferred The aspect is also the same. R ¹ and R ⁵ , and R ⁵ and R ⁶ may be independently bonded to each other to form a 5-membered or 6-membered ring.

In general formula (2), R ³ and R ⁴ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkylsulfonyl group. Represents an arylsulfonyl group or a sulfamoyl group. Among these, a hydrogen atom, an aromatic group, a heterocyclic group, an acyl group, an alkylsulfonyl group, and an arylsulfonyl group are preferable, and a hydrogen atom, an aromatic group, and a heterocyclic group are particularly preferable. Details of each group are as described above.
Q represents a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group. Among these, Q is preferably a group composed of a nonmetallic atom group necessary for forming a 5- to 8-membered ring. This 5- to 8-membered ring may be substituted, may be a saturated ring, or may have an unsaturated bond. Of these, aromatic groups and heterocyclic groups are particularly preferred. Preferred nonmetallic atoms include nitrogen atoms, oxygen atoms, sulfur atoms and carbon atoms.
Specific examples of the 5- to 8-membered ring include, for example, a benzene ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, a cyclohexene ring, a pyridine ring, a pyrimidine ring, a pyrazine ring, a pyridazine ring, a triazine ring, and an imidazole ring. , Benzimidazole ring, oxazole ring, benzoxazole ring, thiazole ring, benzothiazole ring, oxane ring, sulfolane ring, thiane ring and the like.
Each group in the general formula (2) may further have a substituent, and when each of these groups further has a substituent, the substituent described in the above general formula (1) may be used. The group illustrated by group, G, R < ¹ >, R < ² > is mentioned.

Here, Hammett's substituent constant σp value used in the present specification will be described in relation to the substituent Z ¹ .
Hammett's rule was found in 1935 by L.L. in order to quantitatively discuss the effect of substituents on the reaction or equilibrium of benzene derivatives. P. A rule of thumb proposed by Hammett, which is widely accepted today. Substituent constants determined by Hammett's rule include a σp value and a σm value, and these values can be found in many general books. A. Dean, "Lange's and book of Chemistry", 12th edition, 1979 (McGraw-Hill) and "Areas of Chemistry" special edition, 122, 96-103, 1979 (Nankodo).
In the present invention, each substituent is limited or explained by Hammett's substituent constant σp, but this means that it is limited only to a substituent having a known value that can be found in the above book. In addition, even if the value is unknown, it also includes a substituent that would be included in the range when measured based on Hammett's law. The general formulas (1) and (2) include those that are not benzene derivatives, but the σp value is used as a scale indicating the electronic effect of the substituent regardless of the substitution position. In the present invention, the σp value is used in this sense.

Examples of the electron-withdrawing group having a Hammett substituent constant σp value of 0.60 or more include a cyano group, a nitro group, an alkylsulfonyl group (for example, methanesulfonyl group), and an arylsulfonyl group (for example, benzenesulfonyl group). it can.
In addition to the above, an electron-withdrawing group having a Hammett σp value of 0.45 or more includes an acyl group (for example, acetyl group), an alkoxycarbonyl group (for example, dodecyloxycarbonyl group), an aryloxycarbonyl group (for example, m-chlorophenoxycarbonyl). Group), alkylsulfinyl group (for example, n-propylsulfinyl group), arylsulfinyl group (for example, phenylsulfinyl group), sulfamoyl group (for example, N-ethylsulfamoyl group, N, N-dimethylsulfamoyl group), halogen Alkyl group (for example, trifluoromethyl group).
As the electron-withdrawing group having a Hammett substituent constant σp value of 0.30 or more, in addition to the above, an acyloxy group (for example, acetoxy group), a carbamoyl group (for example, N-ethylcarbamoyl group, N, N-dibutylcarbamoyl group) , Halogenated alkoxy groups (for example, trifluoromethyloxy group), halogenated aryloxy groups (for example, pentafluorophenyloxy group), sulfonyloxy groups (for example, methylsulfonyloxy group), halogenated alkylthio groups (for example, difluoromethylthio group) An aryl group (for example, 2,4-dinitrophenyl group, pentachlorophenyl group) substituted with an electron-withdrawing group having two or more σp values of 0.15 or more, and a heterocyclic group (for example, 2-benzoxoxa group) Zolyl group, 2-benzothiazolyl group, 1-phenyl-2-benzimidazoli Group).
Specific examples of the electron-withdrawing group having a σp value of 0.20 or more include a halogen atom in addition to the above.

A particularly preferred combination of substituents as the azo dye represented by the general formula (1) is an embodiment in which two or more of the following (i) to (d) are arbitrarily combined.
(A) R ⁵ and R ⁶ are each preferably a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an alkylsulfonyl group, an arylsulfonyl group or an acyl group, more preferably a hydrogen atom, an alkyl group or an aryl group. A heterocyclic group, and most preferably a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group.
(B) G is preferably a hydrogen atom, a halogen atom, an alkyl group, a hydroxyl group, a “substituted amino group substituted with an alkyl group, an aryl group or a heterocyclic group”, an amide group, more preferably a hydrogen atom, “Substituted amino group substituted with an alkyl group, aryl group or heterocyclic group”, an amide group, most preferably a hydrogen atom, “Substituted amino group substituted with an alkyl group, aryl group or heterocyclic group”, amide It is a group.
(C) A is preferably a pyrazole ring, an imidazole ring, an isothiazole ring, a thiadiazole ring, or a benzothiazole ring, more preferably a pyrazole ring or an isothiazole ring, and most preferably a pyrazole ring.
(D) ^{B 1} and ^{B 2} are each ^-CR 1 =, - a CR ² =, each of these ^{R 1} and ^{R 2} is preferably a hydrogen atom, a halogen atom, a cyano group, a carbamoyl group, a carboxyl group, An alkyl group, a hydroxy group, and an alkoxy group are more preferable, and a hydrogen atom, a cyano group, a carbamoyl group, and an alkyl group are more preferable.

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 various substituents is said preferable group is preferable, and many more various substituents are above-mentioned. A compound that is a preferred group is more preferred, and a compound in which all substituents are the preferred groups described above is most preferred.
Furthermore, the compound represented by the general formula (1) preferably has at least one substituent having 8 or more carbon atoms. Further, this substituent is particularly preferably an alkyl group having 8 or more carbon atoms.

  Specific examples of the compound represented by the general formula (1) are shown below. The present invention is not limited by these specific examples.

  These compounds are disclosed in Japanese Patent No. 4408380, Japanese Patent No. 4642403, Japanese Patent No. 4357383, Japanese Patent No. 4359541, Japanese Patent Application Laid-Open No. 2006-91190, Japanese Patent Application Laid-Open No. 2007-31616, Japanese Patent Application Laid-Open No. 2007-39478, and Japanese Patent No. 4597806. , JP-A-2002-371079, and Japanese Patent No. 4666873.

[Solubility of the azo dye of the present invention]
The azo dye of the present invention is excellent in solubility in a nonpolar solvent, particularly in a hydrocarbon solvent, and has a solubility in n-hexane at 25 ° C. and 0.1 MPa of 1% by mass or more.
The content of 1% by mass or more indicates that the present invention can be applied to a member (for example, a color filter) for manufacturing a display that operates based on the principle of the electrowetting method or a display that operates based on the electrophoresis method.
Hereinafter, “the solubility of n-hexane at 25 ° C. and 0.1 MPa of the dye” is also simply referred to as “solubility”.
When the azo dye of the present invention is applied to a member (for example, a color filter) for producing a display that operates on the principle of electrowetting method or a display that operates on electrophoresis method, the solubility is 3 mass. % Or more, preferably 5% by mass or more. The higher the solubility, the better, but it is usually about 80% by mass or less.

<Coloring composition>
The coloring composition of the present invention contains at least one azo dye of the present invention described above and a nonpolar solvent.
The coloring composition of the present invention may contain only one kind of the azo dyes of the present invention or may contain two or more kinds, and the ratio of each dye when two or more kinds of azo dyes are contained is Is optional.
Moreover, the pigment | dye in the coloring composition of this invention may consist only of the azo dye of this invention, and in order to make it a desired color tone, it may contain another pigment | dye. For example, the azo dye of the present invention may be mixed with a dye having a structure different from that of the azo dye of the present invention to make it black.

[Other dyes]
Other dyes having a structure different from that of the azo dyes of the present invention that may be contained in the coloring composition of the present invention include dyes having solubility and dispersibility in the nonpolar solvent to be used. It can be arbitrarily selected within the range not impairing the effect of the azo dye of the invention.
For example, when the coloring composition of the present invention is used for a display device that operates on the principle of the electrowetting method, the other coloring matter that may be contained in the coloring composition of the present invention is an aliphatic hydrocarbon solvent or the like. Arbitrary pigment | dyes can be used from what melt | dissolves in a nonpolar solvent. Specific examples include Oil Blue N (alkylamine-substituted anthraquinone), Solvent Green, Sudan Red, Sudan Black, and the like.

[Non-polar solvent]
Examples of the nonpolar solvent for dissolving the dye include aliphatic hydrocarbon solvents such as n-hexane, n-decane, dodecane, tetradecane, and hexadecane.
The content of the nonpolar solvent in the colored composition of the present invention constitutes the remainder excluding the azo dye of the present invention and other dyes.

[Other ingredients]
The coloring composition of the present invention may further contain various additives such as an arbitrary ultraviolet absorber and antioxidant as necessary.
Although there is no restriction | limiting in particular in content of an additive, Usually, it is used at about 20 mass% or less with respect to the total amount of a coloring composition.

  The azo dye of the present invention, and other dyes used as necessary, are dissolved in a non-polar solvent such as the aliphatic hydrocarbon solvent described above, and used for a display that operates on the principle of the electrowetting method. Ink.

  About the density | concentration (C) of the azo dye of this invention in the coloring composition of this invention, it prepares by arbitrary density | concentrations according to the objective. When used as a purple pigment for a display device that operates on the principle of the electrowetting method, usually at a concentration of 0.2% by mass or more, depending on the required εC value (ε is the extinction coefficient of the colored composition) Used diluted in nonpolar solvent.

<Display device>
Since the azo dye of the present invention has an excellent solubility in a nonpolar solvent, particularly a hydrocarbon solvent, a display device such as a display, particularly a display device (display) that operates on the principle of the electrowetting method. It is useful as a dye used for a display device (display) that operates by electrophoresis or electrophoresis. Therefore, the colored composition of the present invention is used for producing a color filter or the like of these display devices.

The principle of the electrowetting method is described in International Publication No. 2005-098524. This principle is associated with two switchable states that depend on the wettability of a polymer solid with a hydrophobic surface against a hydrophobic liquid.
The hydrophobic polymer solid preferably exhibits a white color. The hydrophobic liquid and the solid are further surrounded by a hydrophilic liquid (for example, water). A voltage difference is generated by the voltage applied between the hydrophilic liquid and the hydrophobic solid, resulting in a change in the surface tension of the hydrophobic liquid, which retreats the applied potential. Thereby, the hydrophobic liquid will cover only a part of the pixel bottom, which is preferably white, or not completely covered. This change in surface tension when the maximum voltage is applied and when no voltage is applied can be perceived by the viewer as an “on” or “off” state of the pixel. In the “on” state, the pixel is white, and in the “off” state, a color optical impression is produced.

  Electrowetting technology in displays has many advantages, such as low energy consumption compared to other display technologies, and quick switching times of pixel states, which is essential for video use. In addition, the pixels of the display can exhibit a variety of colors because the coloration of the pixels is guaranteed by the dye dissolved in the hydrophobic liquid. The dye must be insoluble in the hydrophilic liquid. Thereby, a transmissive display based on red, green, blue (“RGB”) and black, or a reflective display based on cyan, magenta, yellow (“CMY”) and black can be realized.

  The change in the surface tension of the hydrophobic liquid is proportional to the applied voltage. Therefore, various gray scales can be expressed in the pixel according to the voltage, and a high-quality image can be generated on the display.

  In addition to displays, electrowetting can be used for optical filters, adaptive lenses, and lab-on-chip technology.

Electrophoresis is a principle that utilizes a phenomenon in which charged particles dispersed in a solvent move by an electric field, and has the advantage of low power consumption and no viewing angle dependency. .
A display that operates based on the principle of electrophoresis is arranged in a liquid phase by placing a dispersion obtained by adding dispersed particles in a colored solution between opposing substrates and applying a voltage of about several volts between the substrates. The particles are moved to perform image display. For example, it is conceivable to form the display by using the colored composition of the present invention as a colored solution, microencapsulating the dispersion, and disposing it between opposing substrates.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof.

[Examples 1 to 5]
A coloring composition (ink) was prepared by dissolving 3% by mass of each of the dyes represented by the exemplary compounds F-1, 2, 3, 4, and 9 in a solvent (n-hexane [n-hexane]). . About the obtained coloring composition (ink), the color of the coloring composition, the absorption maximum wavelength (λmax), the absorbance (abs), the extinction coefficient (ε), and the solubility (mass%) of each dye in the solvent were evaluated. . The evaluation results are shown in Table 1.

-Each physical property evaluation method-
1. Solution Color The color of the coloring composition was judged visually.

2. Absorption maximum wavelength, absorbance, and extinction coefficient of the colored composition The absorption maximum wavelength (λmax) and absorbance (abs) of the colored composition were measured with a visible light absorptiometer (Shimadzu UV-1800PC), and the absorbance (abs). From this, the extinction coefficient (ε) was calculated according to the Lambert-Beer law.

3. Solubility in n-hexane The solubility of each dye in n-hexane as a solvent was measured as follows.
Each dye is dissolved in n-hexane heated at 50 ° C. to prepare a saturated solution, and the obtained saturated solution is left in an environment of 25 ° C. and 0.1 MPa for 1 hour, and the precipitated dye is filtered, The solubility (mass%) with respect to n-hexane of each pigment | dye in 25 degreeC and 0.1 Mpa was computed by measuring precipitation amount.

[Comparative Examples 1 and 2]
In Example 1, instead of using Exemplified Compound F-1 as a dye, the same as in Example 1 except that the following Compounds C-101 and C-102 were used, respectively, the color of the colored composition, the absorption maximum wavelength Absorbance, extinction coefficient, and solubility were evaluated. The evaluation results are shown in Table 1.

From Table 1, Exemplified Compounds F-1, 2, 3, 4, and 9 which are azo dyes of the present invention are more effective against hydrocarbon solvents than C-101 and C-102 which are comparative compounds. It was found that the composition showed high solubility, and the obtained colored composition had a large extinction coefficient.
Therefore, a color composition of the display device that operates on the principle of the electrowetting method or the display device that operates on the electrophoresis method is suitably manufactured by using the colored composition containing the exemplary compounds F-1, 2, 3, 4, and 9. You can see that you can.

Claims (4)

An azo dye represented by the following general formula (1) and having a solubility in n-hexane at 25 ° C. and 0.1 MPa of 1% by mass or more.

A represents a residue of a 5-membered heterocyclic diazo component A-NH _2. B ¹ and ^{B 2} are each ^{independently, -CR 1 =, - CR 2} =, or a nitrogen atom, ^{B 1} and ^{B 2} do not simultaneously represent a nitrogen atom. R ⁵ and R ⁶ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkylsulfonyl group, arylsulfonyl group, or Represents a sulfamoyl group. G, R ¹ and R ² are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, acyl group, Substitution substituted with hydroxyl group, alkoxy group, aryloxy group, silyloxy group, acyloxy group, carbamoyloxy group, heterocyclic oxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, alkyl group or aryl group or heterocyclic group Amino group, acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkylsulfonylamino group, arylsulfonylamino group, aryloxycarbonylamino group, nitro group, alkylthio group, ant Thio group, an alkylsulfonyl group, an arylsulfonyl group, an alkylsulfinyl group, an arylsulfinyl group, a sulfamoyl group, a sulfo group, or a heterocyclic thio group. R ¹ or R ² and R ⁵ , and R ⁵ and R ⁶ of B ¹ or B ² may be independently bonded to each other to form a 5-membered or 6-membered ring. The azo dye according to claim 1, wherein the azo dye represented by the general formula (1) is a compound represented by the following general formula (2).

Z ¹ represents an electron-withdrawing group having a Hammett's substituent constant σp value of 0.20 or more, and Z ² represents a hydrogen atom, an aliphatic group, an aromatic group, or a heterocyclic group. R ¹ and R ² are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, acyl group, hydroxyl group , Substituted amino groups substituted by alkoxy groups, aryloxy groups, silyloxy groups, acyloxy groups, carbamoyloxy groups, heterocyclic oxy groups, alkoxycarbonyloxy groups, aryloxycarbonyloxy groups, alkyl groups or aryl groups or heterocyclic groups , Acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkylsulfonylamino group, arylsulfonylamino group, aryloxycarbonylamino group, nitro group, alkylthio group, aryl O group, an alkylsulfonyl group, an arylsulfonyl group, an alkylsulfinyl group, an arylsulfinyl group, sulfamoyl group, sulfo group or a heterocyclic thio group,. R ³ and R ⁴ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkylsulfonyl group, arylsulfonyl group, or sulfamoyl. Represents a group. R ⁵ and R ⁶ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkylsulfonyl group, arylsulfonyl group, or Represents a sulfamoyl group. R ¹ and R ⁵ , and R ⁵ and R ⁶ may be independently bonded to each other to form a 5-membered or 6-membered ring. Q represents a hydrogen atom, an aliphatic group, an aromatic group, or a heterocyclic group.   A coloring composition comprising the azo dye according to claim 1 or 2 and a nonpolar solvent, which is used for producing a color filter of a display device that operates on the principle of an electrowetting method.   A coloring composition comprising the azo dye according to claim 1 or 2 and a nonpolar solvent, which is used for producing a color filter of a display device operating by electrophoresis.