JP2011105798A - Water-soluble azo compound or salt thereof, ink composition and colored article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a yellow colorant which has a hue having high visibility suitable for ink jet recording, is high in the various fastness of recorded materials, and is excellent in storage stability, and to provide an ink composition containing the same. <P>SOLUTION: There are provided a water-soluble azo compound represented by formula (1) (wherein, Q is a halogen atom; Z is H, a carboxy group, or sulfo group; (x) is an integer of 2 to 4; and (y) is an integer of 0 to 2) or a salt thereof, and an ink composition containing the same. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a water-soluble disazo compound or a salt thereof, an ink composition containing the same, and a colored body colored with these.

Among various color recording methods, various ink ejection methods have been developed as recording methods using an ink jet printer, which is one of the representative methods. These all generate ink droplets and attach them to various recording materials (paper, film, fabric, etc.) for recording. In this method, since the recording head and the recording material are not in direct contact with each other, no noise is generated and the method is quiet. In addition, due to the features of miniaturization, high speed, and easy colorization, it has been spreading rapidly in recent years, and significant growth is expected in the future. Conventionally, as inks such as fountain pens and felt pens and inks for ink jet recording, inks in which a water-soluble coloring matter (dye) is dissolved in an aqueous medium have been used. In general, a water-soluble organic solvent is added to these water-based inks in order to prevent clogging of ink at a pen tip or an ink discharge nozzle. These inks give a recorded image of sufficient density, do not cause clogging of the pen tip and nozzles, have good drying properties on the recording material, have little bleeding, and have excellent storage stability. Such performance is required.

Ink jet nozzle clogging occurs when the water in the ink evaporates in the vicinity of the nozzle before other solvents and additives, and the pigment solidifies and precipitates when the composition state is low in water and high in solvents and additives. There are many things that come from doing. Accordingly, one of the very important required performances is that solids are not easily deposited even when the moisture content in the ink is low. For this reason, high solubility in solvents and additives is one of the properties required for pigments. As a method for eliminating nozzle clogging, a method using a dye having a high printing density is known. By using a pigment having a high printing density, the pigment content in the ink can be reduced while maintaining the conventional printing density. This not only makes it difficult to precipitate the dye, but is also advantageous in terms of cost, and development of a dye having a high printing density is desired.

By the way, in order to record an image or character information on a color display of a computer in color by an ink jet printer, generally a subtraction method using four colors of ink of yellow (Y), magenta (M), cyan (C), and black (K). Mixed colors are used, whereby the recorded image is expressed in color. In order to reproduce the additive color mixture image with red (R), green (G), and blue (B) on a CRT (CRT) display etc. as faithfully as possible with the subtractive color mixture image, each dye used in the ink, especially Y, Each of M and C is desired to have a hue close to a standard color and to be clear. The clearness mentioned here generally means having a high saturation. When the three primary colors Y, M, and C with low saturation are used, the color area that can be expressed in a single color or mixed color becomes narrow, and the range of the color area that is desired to be expressed may be insufficient. For this reason, development of highly saturated pigments and inks containing them is desired. In addition, the ink performance is required to be stable for long-term storage, high in the density of the recorded image, and excellent in fastness such as water resistance, moisture resistance, light resistance and gas resistance. It is done. Here, the gas resistance means a gas having an oxidizing action (also called an oxidizing gas) present in the air reacts with a dye (dye) of a recorded image on the recording paper or in the recording paper to change the recorded image. It is resistance to the phenomenon of fading. Among oxidizing gases, ozone gas is considered to be a main causative substance that promotes the discoloration and fading phenomenon of ink jet recorded images. Since this discoloration phenomenon is characteristic of ink jet recorded images, improvement of ozone gas resistance is an important technical problem in this field.

With the recent development of inkjet technology, the speed of inkjet recording (printing) has been remarkably improved. For this reason, similar to laser printers using electronic toner, there is a market trend to use inkjet printers for printing documents on plain paper, which is the main application in office environments. Inkjet printers have the advantage that the type of recording paper is not limited and the price of the printer itself is low, and it is becoming increasingly popular especially in small to medium-sized office environments such as small offices and home offices (SOHO). As described above, when an inkjet printer is used for printing on plain paper, hue, color (printing) density, and water resistance tend to be more important among the quality required for printed matter. In order to satisfy these performances, a method using a pigment ink has been proposed. However, since pigment ink does not dissolve in water-based ink, it does not enter a solution state, but is a dispersed ink. Therefore, when this is used for ink jet recording, there are problems with the stability of the ink itself and the nozzles of the recording head. Problems such as clogging occur. In addition, when pigment ink is used, there is often a problem in abrasion resistance. In the case of a dye ink, such a problem is considered to be relatively difficult to occur. However, in particular, the water resistance is extremely inferior to that of a pigment ink, and an improvement to the problem is strongly desired. In addition, unlike pigment ink, dye ink tends to cause a problem that a dye attached to the surface of plain paper by ink jet recording penetrates more quickly toward the back side of the paper, resulting in a decrease in color density.

One method for obtaining a photographic image-recorded inkjet image is to provide an ink-receiving layer on the surface of a recording material. The ink receiving layer provided for such a purpose often contains a porous white inorganic substance in order to speed up drying of the ink and to reduce bleeding of the pigment with high image quality. However, particularly in such a recording material, the discoloration due to the ozone gas is noticeable. With the recent spread of digital cameras and color printers, there are increasing opportunities to print images obtained with digital cameras and the like as photographic image quality at home, so the above-mentioned color change of recorded images due to oxidizing gas is regarded as a problem. . Compared to the other three primary colors, magenta and cyan, yellow dyes have been proposed that have good resistance to oxidizing gas as well as light resistance. However, a yellow pigment and yellow ink for ink-jet recording that sufficiently satisfy the high sharpness and various fastnesses required by the market have not been obtained yet.

Examples of known yellow pigments for inkjet which are excellent in water solubility and sharpness include C.I. I. (Color index) Direct yellow 132 is exemplified. In recent years, a plurality of highly fast azo dyes have been proposed due to the development of yellow dyes for ink jet recording.
Patent Document 1 discloses a yellow anionic azo compound having light resistance and water fastness.
Patent Document 2 discloses a yellow water-soluble azo compound that is highly soluble in water and has moisture resistance, ozone gas resistance, and light resistance.

JP-A-4-233975 JP 2006-152264 A

The present invention provides a water-soluble yellow pigment (compound) having high solubility in water, excellent chroma of recorded images, and excellent light fastness, and a yellow ink composition for various recordings containing the same, particularly for inkjet recording. With the goal.

As a result of intensive studies, the present inventors have found that a water-soluble disazo compound represented by a specific formula and an ink composition containing the same solve the above-mentioned problem. The invention has been completed. That is, the present invention
1)
A water-soluble azo compound represented by the following formula (1) or a salt thereof,

(In the formula, Q represents a halogen atom, Z represents a hydrogen atom, a carboxy group, or a sulfo group, x represents an integer of 2 to 4, and y represents an integer of 0 to 2, respectively).

2)
In the formula (1), Q is a chlorine atom, Z is a sulfo group, x is 3, and y is an integer of 0 or 1, or the water-soluble azo compound or salt thereof according to 1) above,
3)
The water-soluble azo compound or a salt thereof according to the above 1) represented by the following formula (2):

4)
An ink composition containing the water-soluble azo compound or salt thereof according to any one of 1) to 3) above;
5)
The ink composition as described in 4) above, further comprising a water-soluble organic solvent,
6)
The ink composition according to 4) or 5), which is for inkjet recording;
7)
An ink jet recording method in which the ink composition according to any one of 4) to 6) above is used as an ink, and ink droplets of the ink are ejected in accordance with a recording signal to adhere to a recording material, and recording is performed;
8)
The inkjet recording method according to 7) above, wherein the recording material is an information transmission sheet,
9)
The inkjet recording method according to 8), wherein the information transmission sheet is a sheet having a paper or an ink receiving layer containing a porous white inorganic substance,
10)
(A) The water-soluble azo compound or a salt thereof according to any one of 1) to 3) above,
(B) an ink composition containing the water-soluble azo compound or salt thereof according to any one of 1) to 3) above;
(C) A colored body colored with any one of the water-soluble azo compound or salt thereof according to any one of 1) to 3) above and an ink composition containing a water-soluble organic solvent,
11)
A colored body colored by the ink jet recording method described in 7) above;
12)
An ink jet printer loaded with a container containing the ink composition according to 4) above,
About.

The water-soluble azo compound of the present invention represented by the formula (1) or a salt thereof has high solubility in water, and for example, in the process of producing the ink composition of the present invention containing the compound or a salt thereof, It has the feature of good filterability for membrane filters. In addition, an image recorded with the ink composition of the present invention containing the compound of the present invention is excellent in saturation and light resistance as compared with the image using the conventional compound. As described above, the water-soluble azo compound of the present invention represented by the formula (1) or a salt thereof, and the ink composition containing the same are extremely useful for various recording ink applications, particularly ink jet recording ink applications. It is.

The present invention will be described in detail.
The water-soluble azo compound of the present invention represented by the formula (1) or a salt thereof is a water-soluble yellow dye. In the present specification, unless otherwise specified, acidic functional groups such as sulfo group and carboxy group are represented in the form of free acid. Further, as described above, the present invention includes both the water-soluble azo compound represented by the formula (1) or a salt of the compound, but it is complicated to always describe both of them as “compound or salt thereof”. is there. Therefore, unless otherwise specified, for convenience, the “water-soluble azo compound of the present invention or a salt thereof” including both the “water-soluble azo compound of the present invention” will be simply described as “the (water-soluble azo) compound of the present invention”.

The compound of the present invention is represented by the formula (1). In formula (1), Q represents a halogen atom.
Specific examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. A fluorine atom or a chlorine atom is preferable, and a chlorine atom is particularly preferable.

In formula (1), Z represents a hydrogen atom, a carboxy group, or a sulfo group, preferably a sulfo group.

In the formula (1), x represents an integer of 2 to 4, preferably 3.
Y represents an integer of 0 to 2, preferably 0 or 1, more preferably 1.

Of the above Q, Z, x, and y, a compound in which preferable ones are combined is more preferable, and a compound in which more preferable ones are combined is more preferable. The same applies to combinations of preferable and more preferable ones.

The compound of the present invention represented by the formula (1) can be produced, for example, as follows. In addition, Q, x, and y that are appropriately used in the following formulas (A) to (F) represent the same meaning as in the formula (1).
In accordance with the method described in JP-A-2004-75719, a compound of the following formula (A) obtained using a commercially available 2-amino-4-halogenophenol as a raw material is converted into methyl-form using sodium bisulfite and formalin. Convert to ω-sulfonic acid derivative (B). Next, by a conventional method, 5-aminoisophthalic acid represented by the following formula (C) is diazotized, and the methyl-ω-sulfonic acid derivative of the formula (B) obtained above and a reaction temperature of 0 to 15 ° C., A coupling reaction is carried out at a pH of 2 to 4, followed by a hydrolysis reaction at a reaction temperature of 80 to 95 ° C. and a pH of 10.5 to 11.5, whereby a compound of the following formula (D) is obtained.

Subsequently, the compound of the above formula (D) (2 equivalents) and cyanuric halide (1 equivalent), for example, cyanuric chloride (1 equivalent) are condensed at a reaction temperature of 15 to 45 ° C. and pH of 5 to 8, to obtain the following formula. The compound (E) is obtained.

Further, the chlorine atom on the triazine ring in the obtained compound of the formula (E) is substituted with a primary amine represented by the following formula (F) under the conditions of a reaction temperature of 75 to 90 ° C. and a pH of 7 to 9. Thus, the compound of the present invention represented by the formula (1) can be obtained.

Examples of the compound of the formula (F) include 2-aminobenzenesulfonic acid, 3-aminobenzenesulfonic acid, 4-aminobenzenesulfonic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, aniline. Specific examples include benzylamine, phenethylamine, 4-aminomethylbenzenesulfonic acid, 4-aminoethylbenzenesulfonic acid, 4-aminomethylbenzoic acid, and the like.

Specific examples of the compound of the present invention represented by the formula (1) are shown in Table 1 below. In Table 1, acidic functional groups such as carboxy groups and sulfo groups are represented in the form of free acids.

The compound of the formula (1) exists also as a free acid or a salt thereof. Examples of the salt of the compound of the formula (1) include salts with inorganic or organic cations. Specific examples of the inorganic cation salt include alkali metal salts such as lithium salts, sodium salts, potassium salts and the like; and ammonium salts (NH ₄ ⁺ ). Examples of the organic cation include, but are not limited to, quaternary ammonium represented by the following formula (3).

In the formula (3), Z ^{1 to} Z ⁴ each independently represent a hydrogen atom, a C1-C4 alkyl group, a hydroxy C1-C4 alkyl group or a hydroxy C1-C4 alkoxy C1-C4 alkyl group, and Z ^{1 to} Z ⁴ At least one of is a group other than a hydrogen atom.

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

Preferred among the salts are alkali metal salts such as sodium, potassium and lithium; organic quaternary ammonium salts such as monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine and triisopropanolamine salts; And ammonium salt; and the like. Of these, lithium salts, sodium salts, and ammonium salts are more preferable.

As will be apparent to those skilled in the art, the salt or free acid of the compound of formula (1) can be easily obtained by the following method or the like. For example, a method of adding a water-soluble organic solvent such as acetone or C1-C4 alcohol to the reaction solution after the final step in the synthesis reaction of the compound of formula (1) or an aqueous solution containing the compound of formula (1) A sodium salt of the compound of the formula (1) can be obtained as a wet cake by filtering and separating the solid precipitated by a method such as salting out by adding sodium chloride; Further, after dissolving the obtained sodium salt wet cake in water, an acid such as hydrochloric acid is added to adjust the pH appropriately, and the precipitated solid is separated by filtration, whereby the free acid of the compound of formula (1) is obtained. Or a mixture of a free acid and a sodium salt in which a part of the compound of the formula (1) is a sodium salt.
Also, after dissolving the obtained sodium salt wet cake or its dry solid in water, an ammonium salt such as ammonium chloride is added, and an acid such as hydrochloric acid is added to adjust the pH appropriately, for example, to pH 1 to 3, By separating the precipitated solid by filtration, an ammonium salt of the compound of the formula (1) can be obtained. A mixture of an ammonium salt of the compound of formula (1) and a sodium salt of the compound of formula (1) by appropriately adjusting the amount or / and pH of ammonium chloride to be added; or the free acid of the compound of formula (1) And a mixture of ammonium salts;
Further, as described later, a free acid solid can be obtained directly by adding a mineral acid (for example, hydrochloric acid, sulfuric acid, etc.) to the reaction solution after completion of the reaction. In this case, a wet cake of the free acid of the compound of formula (1) is added to water and stirred, for example, potassium hydroxide; lithium hydroxide; ammonia water; or water of organic quaternary ammonium of formula (3) By adding an oxide; etc. to form a salt, a potassium salt, a lithium salt, an ammonium salt, or a quaternary ammonium salt according to each added compound can be obtained. By limiting the number of moles of the above-mentioned hydroxide and the like to the number of moles of free acid, for example, a mixed salt of lithium salt and sodium salt, etc .; Etc. can also be prepared. The salt of the compound of the formula (1) may change the physical properties such as solubility or the ink performance when used as an ink depending on the type of the salt. For this reason, it is also preferable to select the type of salt according to the intended ink performance.

After completion of the reaction, the compound of the present invention of the formula (1) can be isolated as a solid free acid by adding a mineral acid such as hydrochloric acid, and the resulting free acid solid is water or, for example, hydrochloric acid water or the like. By washing with acidic water, inorganic salts (inorganic impurities) contained as impurities, such as sodium chloride and sodium sulfate, can be removed. As described above, the free acid of the compound of the present invention obtained as described above is obtained by treating the obtained wet cake or its dried solid with a desired inorganic or organic base in water to give a salt of the corresponding compound. Solution. Examples of the inorganic base include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate; and ammonium hydroxide (ammonia water). Etc. Examples of the organic base include, but are not limited to, organic amines corresponding to the quaternary ammonium represented by the formula (3), for example, alkanolamines such as diethanolamine and triethanolamine.

The compounds of the present invention are suitable for the dyeing of natural and synthetic fiber materials or blends, and also for the production of writing inks and ink jet recording ink compositions. For example, the reaction liquid after completion of the final step in the synthesis reaction of the compound of the present invention represented by the formula (1) can be directly used for the production of the ink composition of the present invention. However, for example, after the reaction liquid or the like is dried by the above-described method or a method such as spray drying to isolate the compound, the obtained compound can be processed into an ink composition.

In the ink composition of the present invention, the compound of the formula (1) is dissolved in water or a mixed solution (also referred to as an aqueous medium) of water and a water-soluble organic solvent (an organic solvent that can be mixed with water). An ink preparation agent is added as necessary. When this ink composition is used as an ink for an ink jet printer, a metal cation chloride contained as an impurity, such as sodium chloride; sulfate, such as sodium sulfate; Is preferred. In this case, for example, the total content of sodium chloride and sodium sulfate is about 1% by mass or less with respect to the total mass of the compound of formula (1), and the lower limit is 0% by mass, that is, below the detection limit of the detection instrument. good. As a method for producing a compound having a small amount of inorganic impurities, for example, a method using a known reverse osmosis membrane; or a dry product or a wet cake of the compound of the present invention, for example, acetone or C1-C4 alcohol (for example, methanol, ethanol, In addition to a water-soluble organic solvent such as isopropanol or the like, or a water-containing water-soluble organic solvent, suspension purification or crystallization methods, and the like can be mentioned. Desalination treatment or the like may be performed by these methods.

In the ink composition of the present invention, the compound of the formula (1) is usually 0.1 to 20% by mass, preferably 1 to 10% by mass, more preferably 2 to 8% by mass in the total mass of the ink composition. contains.

The ink composition of the present invention is prepared using water as a medium, and may optionally contain a water-soluble organic solvent and an ink preparation agent as long as the effects of the present invention are not impaired.

The water-soluble organic solvent dissolves the dye; prevents the composition from drying (maintains a wet state); adjusts the viscosity of the composition; promotes penetration of the dye into the recording material; adjusts the surface tension of the composition; It is used for the purpose of effects such as defoaming of a product, and is preferably contained in the ink composition of the present invention.

Examples of the ink preparation agent include antiseptic / antifungal agents, pH adjusting agents, chelating reagents, rust preventive agents, ultraviolet absorbers, viscosity adjusting agents, dye dissolving agents, antifading agents, surface tension adjusting agents, antifoaming agents, etc. Known additives may be mentioned.

The content of the water-soluble organic solvent is 0 to 60% by mass, preferably 10 to 50% by mass, and the ink preparation agent is 0 to 20% by mass, preferably 0, based on the total mass of the ink composition of the present invention. It is good to use ~ 15 mass%. In the ink composition of the present invention, the balance other than the compound of the formula (1), the water-soluble organic solvent, and the ink preparation agent is water.

Examples of the water-soluble organic solvent include C1-C4 alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol and tert-butanol; N, N-dimethylformamide or N, Amides such as N-dimethylacetamide; 2-pyrrolidone, N-methyl-2-pyrrolidone, hydroxyethyl-2-pyrrolidone, 1,3-dimethylimidazolidin-2-one or 1,3-dimethylhexahydropyrimido- Heterocyclic ketones such as 2-one; ketones or ketoalcohols such as acetone, methyl ethyl ketone, 2-methyl-2-hydroxypentan-4-one; cyclic ethers such as tetrahydrofuran, dioxane; ethylene glycol, 1, 2- or 1 , 3-propylene glycol, 1,2 Or mono- having C2-C6 alkylene units such as 1,4-butylene glycol, 1,6-hexylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, or thiodiglycol , Oligo or polyalkylene glycol or thioglycol; polyol (preferably triol) such as trimethylolpropane, glycerin, hexane-1,2,6-triol; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol Monoethyl ether, diethylene glycol monobutyl ether (butyl carbitol), triethylene glycol Glycol monomethyl ether, C1-C4 monoalkyl ether of polyhydric alcohol such as triethylene glycol monoethyl ether; .gamma.-butyrolactone; or dimethyl sulfoxide and the like.

The water-soluble organic solvent includes substances that are solid at room temperature, such as trimethylolpropane. However, even if the substance is a solid, it shows water solubility, and an aqueous solution containing the substance shows the same properties as a water-soluble organic solvent and can be used for the same purpose. Therefore, in this specification, for the sake of convenience, even such a solid substance is included in the category of a water-soluble organic solvent as long as it can be used for the same purpose.

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

Examples of the antiseptic / antifungal agent include organic sulfur, organic nitrogen sulfur, organic halogen, haloallylsulfone, iodopropargyl, N-haloalkylthio, benzothiazole, nitrile, pyridine, 8-oxyquinoline, isothiazoline, dithiol, pyridine oxide, nitropropane, organotin, phenol, quaternary ammonium salt, triazine, thiadiazine, anilide, adamantane, dithiocarbamate, bromo Indanone-based compounds, benzyl bromacetate-based compounds, and inorganic salt-based compounds are exemplified. Examples of the organic halogen compound include sodium pentachlorophenol, examples of the pyridine oxide compound include sodium 2-pyridinethiol-1-oxide, and examples of the isothiazoline compound include 1,2-benzisothiazoline. -3-one, 2-n-octyl-4-isothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one Examples thereof include magnesium chloride, 5-chloro-2-methyl-4-isothiazolin-3-one calcium chloride, and 2-methyl-4-isothiazolin-3-one calcium chloride. Other antiseptic / antifungal agents include sodium acetate, sodium sorbate, sodium benzoate and the like; and trade names Proxel ^RTM GXL (S) and Proxel ^RTM XL-2 (S) manufactured by Arch Chemical Co., respectively. It is done. In the present specification, the superscript “ ^RTM ” means a registered trademark.

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

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

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

Examples of the ultraviolet absorber include a benzophenone compound, a benzotriazole compound, a cinnamic acid compound, a triazine compound, and a stilbene compound. So-called fluorescent brighteners can also be used.

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

Examples of the dye solubilizer include urea, ε-caprolactam, ethylene carbonate, and the like. It is preferred to use urea.

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

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

Anionic surfactants include alkyl sulfocarboxylates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, N-acyl amino acids and salts thereof, N-acyl methyl taurate, alkyl sulfate polyoxyalkyl ether sulfates Salt, alkyl sulfate polyoxyethylene alkyl ether phosphate, rosin acid soap, castor oil sulfate ester, lauryl alcohol sulfate ester, alkylphenol type phosphate ester, alkyl type phosphate ester, alkylaryl sulfonate, diethylsulfate , Diethylhexyl sulfosuccinate, dioctyl sulfosuccinate and the like.

Examples of the cationic surfactant include 2-vinylpyridine derivatives and poly-4-vinylpyridine derivatives.

Amphoteric surfactants include lauryldimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, coconut oil fatty acid amidopropyldimethylaminoacetic acid betaine, polyoctylpolyaminoethylglycine, and other imidazoline derivatives. There is.

Nonionic surfactants include ethers such as polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene dodecylphenyl ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene alkyl ether; Ester systems such as polyoxyethylene oleate, polyoxyethylene distearate, sorbitan laurate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, polyoxyethylene monooleate, polyoxyethylene stearate; 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, 3,5-dimethyl -1-hexyne-3-acetylene glycol (alcohol) -based ol; Nissin Chemical Industry Co., Ltd. trade name Surfynol ^RTM 104, 82, 465, Olfine ^RTM STG; SIGMA-ALDRICH Corp. Product Name Tergitol ^RTM 15-S-7;

Examples of antifoaming agents include highly oxidized oils, glycerin fatty acid esters, fluorines, and silicone compounds.

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

In the production of the ink composition of the present invention, there is no particular limitation on the order of dissolving each agent such as an additive. The water used for preparing the ink composition is preferably water with few impurities such as ion exchange water or distilled water. Further, if necessary, after the ink composition is prepared, fine filtration may be performed using a membrane filter or the like to remove impurities in the ink composition. In particular, when the ink composition of the present invention is used as an ink for ink jet recording, it is preferable to perform microfiltration. The pore size of the filter used for microfiltration is usually 1 μm to 0.1 μm, preferably 0.8 μm to 0.1 μm.

The ink composition containing the compound of the present invention is suitable for use in printing, copying, marking, writing, drawing, stamping, or recording (printing), particularly in inkjet recording. In addition, the ink composition of the present invention is less likely to precipitate a solid even when dried in the vicinity of the nozzles of the recording head of an ink jet printer, and for this reason, the recording head is also less likely to be blocked.

As a method for recording on a recording material by the ink jet recording method of the present invention, the following method may be mentioned. That is, a container filled with the ink composition of the present invention is loaded into a predetermined position of an ink jet printer, the ink composition of the present invention is used as ink, and ink droplets of the ink are ejected according to a recording signal to be recorded. This is a method for recording on a material. Some inkjet printers use, for example, a piezo method using mechanical vibration; a bubble jet (registered trademark) method using bubbles generated by heating; and the like. The ink jet recording method of the present invention can be used by any method.

In order to obtain a higher-definition recorded image, there are cases where two types of ink containing the same pigment are loaded into one inkjet printer. The difference between the two types of inks is the pigment content, one of which has a high content and the other of which has a low content, and is used as an ink set. The ink composition of the present invention can also be used as such an ink set. Further, the ink composition of the present invention may be used for one of the ink sets, and a known ink (composition) may be used for the other.

The ink composition of the present invention may be a yellow ink composition containing the compound of the present invention and a known yellow dye for the purpose of fine-tuning the hue within the range that does not impair the effects obtained by the present invention. In addition, the compound of the present invention can be used in combination with a magenta dye or a cyan dye for the purpose of toning other colors such as black ink or for preparing red ink or green ink. Furthermore, for the purpose of obtaining a full-color recorded image, the ink composition of the present invention may be used in combination with inks of various colors such as magenta, cyan, and, if necessary, green, blue (or violet), red, and black. it can. In this case, each color ink may be filled in each container, and these containers may be loaded into a predetermined position of the ink jet printer and used for ink jet recording.

Examples of the recording material used in the inkjet recording method of the present invention include information transmission sheets such as paper and film, fibers and fabrics (cellulose, nylon, wool, etc.), leather, base materials for color filters, and the like. A transmission sheet is preferred. The information transmission sheet is not particularly limited, and a plain paper as well as a surface-treated sheet, specifically, a paper, synthetic paper, a substrate such as a film provided with an ink receiving layer, or the like is used. The ink receiving layer is a layer having an action such as absorbing ink and accelerating its drying. The ink receiving layer is formed by, for example, impregnating or coating the base material with a cationic polymer; or the inorganic fine particles capable of absorbing the pigment in the ink together with a hydrophilic polymer such as polyvinyl alcohol or polyvinylpyrrolidone, and the surface of the base material. It is provided by the method of coating to; Examples of the inorganic fine particle material capable of absorbing the pigment in the ink include porous silica, alumina sol, and special ceramics. The information transmission sheet having such an ink-receiving layer is usually called an inkjet exclusive paper, an inkjet exclusive film, a glossy paper, or a glossy film. Examples of typical commercially available information transmission sheets having an ink receiving layer include Canon Inc., trade name professional photo paper, Canon Photo Paper / Glossy Pro [Platinum Grade], and Glossy Gold; Seiko Epson Corporation Product name Photo Paper Crispia (High Gloss), Photo Paper (Glossy); Nippon Hewlett-Packard Co., Ltd., Product Name Advanced Photo Paper (Gloss); Fuji Film Co., Ltd., Product Name Image Color Photo Finishing Pro Manufactured by Brother Industries, Ltd., trade name: photographic glossy paper BP71G; Also, plain paper means paper that is not particularly provided with an ink receiving layer, and many different types are commercially available depending on the application. Among commercially available plain papers, for ink-jet recording, double-sided fine plain paper (manufactured by Seiko Epson Corporation); PB PAPER GF-500 (manufactured by Canon Inc.); Multipurpose Paper, All-in-one Printing Paper ( Hewlett Packard). In addition, plain paper copy (PPC) paper or the like whose use is not limited to ink jet recording is also plain paper.

The colored body of the present invention comprises (a) the water-soluble azo compound of the present invention; (b) the ink composition of the present invention containing the compound; or (c) the invention containing the compound and a water-soluble organic solvent. Means a colored material. The substance to be colored is not particularly limited, and examples thereof include, but are not limited to, the recording material described above. Preferably, the above-mentioned recording material is colored. The coloring method for the substance is not particularly limited, and examples thereof include a printing method such as a dip dyeing method, a textile printing method, and screen printing, and the ink jet recording method of the present invention. The ink jet recording method of the present invention is preferable. Among the colored bodies, a colored body colored by the ink jet recording method of the present invention is preferable.

The water-soluble azo compound of the present invention represented by the formula (1) is excellent in solubility in water or a water-soluble organic solvent. Moreover, it has the characteristic that the filterability with respect to a membrane filter, for example in the process of manufacturing the ink composition of this invention is favorable. The ink composition of the present invention is very clear on a recording material such as plain paper and an information transmission sheet having an ink receiving layer, has a high saturation and printing density, and is capable of producing a yellow recorded image of an ideal hue. give. Therefore, it is also possible to faithfully reproduce a photographic color image on paper. In addition, the ink composition of the present invention has very good storage stability without solid deposition, physical property change, hue change, etc. after long-term storage. Even when the ink composition of the present invention is used as an inkjet ink, solid precipitation due to drying of the ink composition in the vicinity of the nozzles is very unlikely to occur, and the ejector (recording head) is not blocked. Further, the ink composition of the present invention uses a continuous ink jet printer, and is used physically even when the ink is recirculated at a relatively long time interval or intermittently used by an on-demand ink jet printer. No change in properties. Further, the image recorded on the information transmission sheet having the ink receiving layer by the ink composition of the present invention has various fastnesses such as water resistance, moisture resistance, ozone gas resistance, abrasion resistance and light resistance, particularly light resistance. For this reason, it has excellent long-term storage stability of photographic images. In addition, compared with conventional inks, color development such as saturation, lightness, and print density on plain paper is also excellent.
As described above, the water-soluble azo compound of the present invention represented by the formula (1) and the ink composition of the present invention containing the compound are extremely useful for various recording ink applications, particularly for ink jet recording ink applications. is there.

EXAMPLES The present invention will be described more specifically with reference to examples. However, the present invention is not limited to the examples. Unless otherwise specified, “part” and “%” in the text are based on mass, and the reaction temperature is the internal temperature. Among the synthesized compounds, those measured for λmax (maximum absorption wavelength) showed measured values in an aqueous solution having a pH of 7-8. Moreover, in each structural formula of the compound obtained in the Example, acidic functional groups, such as a carboxy group and a sulfo group, were described in the form of a free acid. The solubility of the compounds of the present invention obtained in Examples in water at room temperature was 100 g / L or more in all cases.

[Example 1]
(Process 1)
18.1 parts of 5-aminoisophthalic acid was dissolved in 200 parts of water while adjusting the pH to 6 with sodium hydroxide, and then 7.2 parts of sodium nitrite was added. This solution was added dropwise at 0 to 10 ° C. in 200 parts of 5% hydrochloric acid over 30 minutes, followed by stirring at 10 ° C. or lower for 1 hour to carry out a diazotization reaction to prepare a diazo reaction solution.
On the other hand, 26.6 parts of 2- (sulfopropoxy) -5-chloroaniline were dissolved in 130 parts of water while adjusting the pH to 7 with sodium hydroxide, and 10.4 parts of sodium bisulfite and 8.6 parts of 35 Using methyl formalin, a methyl-ω-sulfonic acid derivative was obtained by a conventional method. The obtained methyl-ω-sulfonic acid derivative was added to the previously prepared diazo reaction solution, and the mixture was stirred at 0 to 15 ° C. and pH 2 to 24 for 24 hours. The reaction solution was adjusted to pH 11 with sodium hydroxide, and then stirred at 80 to 95 ° C. for 5 hours while maintaining the same pH. The obtained reaction solution was dropped into 200 parts of 5% hydrochloric acid, and the precipitated solid was separated by filtration to obtain 100 parts of an azo compound represented by the following formula (4) as a wet cake.

(Process 2)
Product name: Leocol ^RTM TD90 (surfactant) 0.10 part was added to 250 parts of ice water and stirred vigorously, and 3.6 parts of cyanuric chloride was added thereto, and 30 to 0 to 5 ° C. Stir for minutes to obtain a suspension. Subsequently, 100 parts of a wet cake of the compound represented by the formula (4) was dissolved in 200 parts of water, and the suspension was dropped into this solution over 30 minutes. After completion of dropping, the mixture was stirred at pH 6-8 and 25-45 ° C. for 6 hours. To the obtained liquid, 31.0 parts of 4-aminomethylbenzenesulfonic acid was added and stirred at pH 7-9 and 75-90 ° C. for 4 hours. After cooling the obtained reaction liquid to 20-25 degreeC, 800 parts of acetone was added to this reaction liquid, and it stirred at 20-25 degreeC for 1 hour. The precipitated solid was separated by filtration to obtain 50.0 parts of a wet cake. This wet cake was dried with a hot air dryer at 80 ° C. to obtain 13.5 parts of a sodium salt (λmax: 403.5 nm) of the water-soluble azo compound of the present invention represented by the following formula (5).

[Example 2]
It is represented by the following formula (6) in the same manner as in Example 1 except that 20.0 parts of benzylamine is used instead of 31.0 parts of 4-aminomethylbenzenesulfonic acid in Example 1 (Step 2). 12.5 parts (λmax: 403.5 nm) of the sodium salt of the water-soluble azo compound of the present invention was obtained.

[Example 3]
In the same manner as in Example 1 except that 30.0 parts of 4-aminomethylbenzoic acid was used instead of 31.0 parts of 4-aminomethylbenzenesulfonic acid in Example 1 (Step 2), the following formula (7 13.0 parts (λmax: 403.5 nm) of the sodium salt of the water-soluble azo compound of the present invention represented by

[Example 4]
In the same manner as in Example 1 except that 35.0 parts of 3-aminobenzenesulfonic acid was used instead of 31.0 parts of 4-aminomethylbenzenesulfonic acid in Example 1 (Step 2), the following formula (8 10.0 parts (λmax: 402.5 nm) of the sodium salt of the water-soluble azo compound of the present invention represented by

[Examples 5 to 8]
(A) Preparation of ink Each of the azo compounds of the present invention obtained in Examples 1 to 4 above (sodium salts of formula (5) to formula (8)) was used as a pigment, and the compositions shown in Table 2 below were used. The ink composition of the present invention was obtained by mixing to obtain a solution. The obtained ink composition was filtered through a 0.45 μm membrane filter to remove impurities, and a test ink was prepared. The pH of this test ink was in the range of 8.0 to 9.5. In Table 2 below, “surfactant” used was the trade name Surfinol ^RTM 104PG50 manufactured by Nissin Chemical Co., Ltd. Preparation of each ink using the compounds obtained in Examples 1 to 4 is referred to as Examples 5 to 8, respectively.

[Comparative Example 1]
Comparative inks were prepared in the same manner as in Examples 5 to 8 except that the compound described in Example 10 of Patent Document 1 was used instead of the compound of the present invention obtained in each Example. This ink preparation is referred to as Comparative Example 1. The structural formula of the compound used in Comparative Example 1 is shown in the following formula (9).

[Comparative Example 2]
Comparative inks were prepared in the same manner as in Examples 5 to 8, except that the coloring matter described in Example 2 of Patent Document 2 was used instead of the compound of the present invention obtained in each Example. This ink preparation is referred to as Comparative Example 2. The structural formula of the compound used in Comparative Example 2 is shown in the following formula (10).

(B) Inkjet recording Each of the inks prepared in Examples 5 to 8 and Comparative Examples was prepared by using an inkjet printer (manufactured by Canon Inc., trade name: PIXUS ^RTM ip4500) with the following three types of glossy paper ( Inkjet recording was performed on an inkjet-only paper. During ink jet recording, an image pattern was prepared so that the reflection density was obtained in several gradations, and a recorded matter having a yellow gradation was obtained. Various tests were performed using the obtained recorded matter as a test piece.

Glossy paper 1:
Product name: Canon Photo Paper / Glossy Professional [Platinum Grade], manufactured by Canon Inc.
Glossy paper 2:
Product name: Photographic paper Krispia (high gloss), manufactured by Seiko Epson Corporation.
Glossy paper 3:
Product name: Photo Glossy Paper BP71G, manufactured by Brother Industries, Ltd.

In the light resistance test, the reflection density was measured for a portion where the reflection density D value of the recorded matter before the test was closest to 1.0. For the measurement of the reflection density, a colorimetry system (trade name: SpectroEye ^RTM , manufactured by X-right) was used. Colorimetry was performed under the conditions of DIN, a viewing angle of 2 degrees, and a light source D65 as a density reference.
Various test methods for recorded images and evaluation methods for test results are described below.

(C) Saturation test The yellow saturation C * value was measured by the colorimetry system for the gradation portion having the highest reflection density among the test pieces. The evaluation criteria are as follows.
C * value is 100 or more ... A
C * value is less than 100 and 95 or more B
C * value is less than 95 …… C
The results are shown in Table 3 below.

(D) Xenon light resistance test Each test piece was installed in a holder, and a xenon weatherometer XL75 [manufactured by Suga Test Instruments Co., Ltd.] was used. Temperature 24 ° C, humidity 60% RH, 0.36W / square meter Irradiated at illuminance for 168 hours. The reflection density of each test piece after the test is measured by the above colorimetry system, and the residual ratio of the dye is calculated by (reflection density after test / reflection density before test) × 100 (%). Rated by stage.
Dye remaining ratio is 65% or more ... A
Dye residual ratio is less than 65% and 60% or more ... B
Dye remaining rate is less than 60% ... C
The results are shown in Table 4 below.

As is clear from the results in Tables 3 and 4, each example showed extremely superior results to each comparative example in both the saturation and xenon light resistance tests.

The water-soluble azo compound of the present invention which is a yellow dye and the yellow ink composition of the present invention containing the same give a recorded image with high saturation. In addition to this, it is excellent in various fastnesses such as light resistance. Therefore, the compound and the ink composition containing the compound are very useful for various recording applications, particularly for inkjet recording applications.

Claims (12)

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

(In the formula, Q represents a halogen atom, Z represents a hydrogen atom, a carboxy group, or a sulfo group, x represents an integer of 2 to 4, and y represents an integer of 0 to 2, respectively). The water-soluble azo compound or a salt thereof according to claim 1, wherein in formula (1), Q is a chlorine atom, Z is a sulfo group, x is 3, and y is an integer of 0 or 1. The water-soluble azo compound or a salt thereof according to claim 1, which is represented by the following formula (2).

An ink composition containing the water-soluble azo compound or a salt thereof according to any one of claims 1 to 3. The ink composition according to claim 4, further comprising a water-soluble organic solvent. The ink composition according to claim 4 or 5, which is for inkjet recording. An ink jet recording method in which recording is performed by using the ink composition according to any one of claims 4 to 6 as ink, and ejecting ink droplets of the ink in accordance with a recording signal to adhere to the recording material. The ink jet recording method according to claim 7, wherein the recording material is an information transmission sheet. 9. The ink jet recording method according to claim 8, wherein the information transmission sheet is a sheet having an ink receiving layer containing plain paper or a porous white inorganic substance. (A) the water-soluble azo compound or salt thereof according to any one of claims 1 to 3;
(B) an ink composition containing the water-soluble azo compound or a salt thereof according to any one of claims 1 to 3, or
(C) A colored body colored with any one of the water-soluble azo compound according to any one of claims 1 to 3 or an ink composition containing a salt thereof and a water-soluble organic solvent. A colored body colored by the ink jet recording method according to claim 7. An inkjet printer loaded with a container containing the ink composition according to claim 4.