JP3398367B2 - Method for producing aqueous ink and dye - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-based ink containing a dye, particularly to a water-based ink suitable for an ink jet recording system and a simple method for producing the dye.

[0002]

2. Description of the Related Art A water-based ink used for recording with a writing instrument or an ink jet recording system basically comprises a dye, water and an organic solvent. However, it is odorous, safe for the human body and the surrounding environment. For consideration, water-based inks containing water as a main solvent are in strong demand, and water-soluble acid dyes, direct dyes, and the like have been put into practical use. In this regard, dyes and water-based inks are required to have various properties. In particular, the water-based ink used for the recording liquid of the ink jet recording system has various required properties described below, but it is the current situation that all of them are not satisfied. (1) Ink viscosity, surface tension, specific electric conductivity, density, pH
The physical properties such as are appropriate. (2) The long-term storage stability of the ink is good. (3) The dissolution stability of the dissolved component is high and the nozzle is not clogged. (4) The fast-drying property of the recording material is good. (5) The recorded image is clear, has no bleeding, has light resistance,
Good water resistance and moisture resistance. As described above, in particular, various characteristics of the ink used in the inkjet recording system are greatly influenced by the characteristics peculiar to the dye, and it is extremely important to create a dye and an aqueous ink satisfying these various conditions.

[0003]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide an aqueous system useful as a recording liquid for an ink jet recording system having high image quality, no blurring, and excellent storage stability, light resistance, moisture resistance, and ejection stability. It is to provide ink.

[0004]

Means for Solving the Problems The inventors of the present invention have made extensive studies to solve these problems, and as a result, completed the present invention. That is, the present invention relates to (1) an aqueous ink containing a dye and an aqueous medium as main components, which contains at least one dye represented by the general formula (A) or a salt thereof as a dye. .

[Chemical 10] [In the formula, R ₁ and R ₃ each independently represent a hydrogen atom, a hydroxyl group, or a halogen atom, and R ₂ and R ₄ are each independently a hydrogen atom, an alkyl group which may be substituted,
Represents an optionally substituted aryl group or an optionally substituted aralkyl group, A is a phenyl group or a naphthyl group (the phenyl group or naphthyl group may be a halogen atom, a hydroxyl group, an amino group, or a substituted group). A good alkyl group, an alkoxy group, a carboxyl group, a carboxylic acid ester group, a carboxylic acid amide group, a sulfonic acid group, or a sulfonic acid amide group), X is an alkylene group, a phenylene group, A xylylene group,
Naphthylene group, biphenylene group, or general formula (2)

[Chemical 11] (In the formula, Z is -CO-, -NHCONH-, -NHC.
SNH-, or formula (3)

[Chemical 12] Represents ) Represents a divalent linking group (these linking groups may be substituted with a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, an amino group, a carboxyl group, or a sulfonic acid group), and m , N each independently represent an integer of 1 to 4. ]

(2) In the general formula (A), R ₁ , R ₃
(3) In the general formula (A), X is a phenylene group which may be substituted (1) or (2). (4) In the general formula (A), A is a naphthyl group (wherein the naphthyl group is a halogen atom, a hydroxyl group, an amino group, an optionally substituted alkyl group, an alkoxy group, or a carboxyl group). Which may be substituted with any of a carboxylic acid ester group, a carboxylic acid amide group, a sulfonic acid group, and a sulfonic acid amide group), (1) to (3) ,

(5) The dye has the formula (B)

[Chemical 13] An aqueous ink for ink jet recording according to (1), which is a dye or salt thereof represented by:

The dye (6) is a compound represented by the formula (B) described in (5) and other general formula (C).

[Chemical 14] [In the formula, R ₅ and R ₇ each independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkoxy group, an amino group, an alkylamino group, a hydroxyl group, or a halogen atom, R ₆ and R ₈ each independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted aryl group, or an aralkyl group, and A is a phenyl group or a naphthyl group (the phenyl group or naphthyl group). The group is a halogen atom, a hydroxyl group, an amino group,
Optionally substituted alkyl group, alkoxy group, carboxyl group, carboxylic acid ester group, carboxylic acid amide group, sulfonic acid group or sulfonic acid amide group), X is 2 Shows a valent linking group, and m ₁ and n ₁ each independently represent an integer of 1 to 4. ] An aqueous ink for ink jet recording containing at least one kind of dye represented by

(7) A dye characterized in that the dye represented by the general formula (C) or a salt thereof is dissolved in water and the pH of the aqueous solution is adjusted to 9 or higher to remove the insoluble matter produced. Production method,

[Chemical 15] [In the formula, R ₅ and R ₇ each independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkoxy group, an amino group, an alkylamino group, a hydroxyl group, or a halogen atom, R ₆ and R ₈ each independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted aryl group, or an aralkyl group, and A is a phenyl group or a naphthyl group (the phenyl group or naphthyl group). The group is a halogen atom, a hydroxyl group, an amino group,
Optionally substituted alkyl group, alkoxy group, carboxyl group, carboxylic acid ester group, carboxylic acid amide group, sulfonic acid group or sulfonic acid amide group), X is 2 Shows a valent linking group, and m ₁ and n ₁ each independently represent an integer of 1 to 4. ]

(8) The dye represented by the general formula (C) described in (7) or a salt thereof is dissolved in water to form an aqueous solution, which is then mixed with a water-soluble organic solvent to crystallize the dye. Insoluble matter produced by dissolving a dye represented by the general formula (C) described in (9) or (7) or a salt thereof in water and adjusting the pH of the aqueous solution to 9 or more. An aqueous solution from which is removed is mixed with a water-soluble organic solvent to crystallize the dye, and a method for producing the dye,

(10) In the general formula (C), X is an alkylene group, a phenylene group, a xylylene group, a naphthylene group, a biphenylene group, or a general formula (5).

[Chemical 16] [In the formula, Z is an oxygen atom, a sulfur atom, -CO-, -NHC.
ONH-, -NHCSNH-, -CH = CH-, or the formula (6).

[Chemical 17] Represents ] A divalent linking group represented by these (these linking groups may be substituted with a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, an amino group, a carboxyl group, or a sulfonic acid group) (7) to A method for producing the dye according to any one of (9),

(11) A method for producing a dye according to any one of (7) to (9), wherein X in the general formula (C) is an optionally substituted phenylene group, and (12) the general formula (C ), A is a naphthyl group (the naphthyl group is a halogen atom, a hydroxyl group, an amino group, an optionally substituted alkyl group, an alkoxy group, a carboxyl group, a carboxylic acid ester group, a carboxylic acid amide group, a sulfonic acid group, (May be substituted with any of sulfonic acid amide groups)
The method for producing a dye according to any one of (7) to (9), and (13) the dye is represented by the above formula (B) (7) to
(14) The method for producing the dye according to any one of (9),
(7) to (13) A water-based ink for inkjet recording, comprising at least one dye produced by the method for producing a dye according to any one of (7) to (13).

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The dye contained in the water-based ink for ink jet recording of the present invention is represented by the above general formula (A), preferably the general formula (1).

[Chemical 18] [In the formula, R ₁ and R ₃ each independently represent a hydrogen atom, a hydroxyl group, or a halogen atom, and R ₂ and R ₄ are each independently a hydrogen atom, an alkyl group which may be substituted,
Represents an optionally substituted aryl group or an optionally substituted aralkyl group, A is a phenyl group or a naphthyl group (the phenyl group or naphthyl group may be a halogen atom, a hydroxyl group, an amino group, or a substituted group). A good alkyl group, an alkoxy group, a carboxyl group, a carboxylic acid ester group, a carboxylic acid amide group, a sulfonic acid group, or a sulfonic acid amide group), X is an alkylene group, a phenylene group, A xylylene group,
Naphthylene group, biphenylene group, or general formula (2)

[Chemical 19] (In the formula, Z is -CO-, -NHCONH-, -NHC.
SNH-, or formula (3)

[Chemical 20] Represents ) Represents a divalent linking group (these linking groups may be substituted with a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, an amino group, a carboxyl group, or a sulfonic acid group). Dye or its salt.

In these general formulas (A) and (1), R ₁ and R ₃ each independently represent a hydrogen atom, a hydroxyl group, or a halogen atom, and R ₂ and R ₄ each independently represent hydrogen. An atom, an optionally substituted alkyl group,
Represents an optionally substituted aryl group or an optionally substituted aralkyl group, A is a phenyl group or a naphthyl group (halogen atom, hydroxyl group, amino group, optionally substituted alkyl group, alkoxy group, carboxyl group , Which may be substituted with any of a carboxylic acid ester group, a carboxylic acid amide group, a sulfonic acid group and a sulfonic acid amide group, and X is an optionally substituted alkylene group or an optionally substituted alkylene group. A phenylene group, an optionally substituted xylylene group, an optionally substituted naphthylene group, or a divalent linking group represented by the general formula (2) (these linking groups are a halogen atom, an alkyl group, an alkoxy group). , Which may be substituted with a hydroxyl group, an amino group, a carboxyl group, or a sulfonic acid group).
In the divalent linking group represented by the general formula (2), Z is-
CO-, -NHCONH-, -NHCSNH-, or formula (3) is represented. Further, in the general formula (A), m and n each independently represent an integer of 1 to 4, and may be the same or different from each other. Preferably, each is an integer of 2 to 3 independently. Of these, a dye represented by the general formula (1) and a salt thereof in which both m and n are 2 are preferable.

The dye represented by the general formula (C) contained in the water-based ink of the present invention, and preferably the general formula (4);

[Chemical 21] [In the formula, R ₅ and R ₇ each independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkoxy group, an amino group, an alkylamino group, a hydroxyl group, or a halogen atom, R ₆ and R ₈ each independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted aryl group, or an aralkyl group, and A is a phenyl group or a naphthyl group (the phenyl group or naphthyl group). The group is a halogen atom, a hydroxyl group, an amino group,
Optionally substituted alkyl group, alkoxy group, carboxyl group, carboxylic acid ester group, carboxylic acid amide group, sulfonic acid group or sulfonic acid amide group), X is 2 A valent linking group is shown. ] In the dye represented by or its salt,

R ₅ and R ₇ are each independently a hydrogen atom,
An alkoxy group, an amino group, a hydroxyl group, or a halogen atom, and R ₆ and R ₈ each independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted aryl group, or an aralkyl group. , A is a phenyl group or a naphthyl group (halogen atom, hydroxyl group, amino group,
Optionally substituted alkyl group, alkoxy group, carboxyl group, carboxylic acid ester group, carboxylic acid amide group, sulfonic acid group or sulfonic acid amide group), X is 2 A valent linking group is shown. X is an optionally substituted alkylene group,
An optionally substituted phenylene group, an optionally substituted xylylene group, an optionally substituted naphthylene group, or a divalent linking group represented by the general formula (5) (these linking groups are halogen atoms. , An alkyl group, an alkoxy group, a hydroxyl group, an amino group, a carboxyl group, or a sulfonic acid group). In the divalent linking group represented by the general formula (5), Z is -NH.
CONH-, -NHCSNH-, or a linking group represented by formula (6).

In the above general formula (A), general formula (1), general formula (C), general formula (4) and a divalent linking group,
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Also, a carboxyl group,
The sulphonic acid groups may be in the free radical or salt form.
Examples of the salt include a carboxylate group which is a salt with an alkali metal or an amine, and a sulfonate group which is a salt with an alkali metal or an amine. The salt is not particularly limited, and examples thereof include lithium. Examples thereof include alkali metal salts such as atoms, sodium atoms and potassium atoms, ammonium salts, organic amine salts such as primary amines, secondary amines and tertiary amines. The alkyl group which may be substituted is not particularly limited, but the total number of carbon atoms is 20 or less, preferably 15 or less, and more specifically, methyl group, ethyl group, n-propyl group, iso- Examples thereof include alkyl groups such as propyl group, n-butyl group, iso-butyl group, tert-butyl group, and halogenated alkyl groups such as trifluoromethyl group and chloroethyl group. The optionally substituted alkoxy group is not particularly limited, but the total carbon number is 20 or less, preferably 15 or less, and more specifically, a methoxy group, an ethoxy group, an n-propoxy group, an iso- A propoxy group, an n-butoxy group,
Examples thereof include an iso-butoxy group and a tert-butoxy group. The optionally substituted aralkyl group is not particularly limited, but includes a total carbon number of 20 or less, preferably 15 or less, and more specifically, a benzyl group, a phenethyl group and the like.

The optionally substituted aryl group is not particularly limited, but has a total carbon number of 20 or less, preferably 15 or less, and more specifically, an unsubstituted phenyl group, chlorophenyl group, bromo group. Phenyl group substituted with halogen atom such as phenyl group and fluorophenyl group, phenyl group substituted with at least one alkyl group such as methyl group, ethyl group, propyl group and butyl group, halogenoalkyl such as trifluoromethyl group Examples thereof include a phenyl group substituted with a group, a hydroxyl group, an amino group, a carboxyl group, a phenyl group substituted with at least one of a sulfonic acid group and the like. The carboxylic acid ester group is not particularly limited, but has a total carbon number of 20 or less, preferably 15 or less, and more specifically, a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group,
Examples thereof include alkoxycarbonyl groups such as butoxycarbonyl group. The carboxylic acid amide group is not particularly limited, but the total carbon number is 20 or less, preferably 15
Hereinafter, more specifically, alkylamino such as aminocarbonyl group, methylaminocarbonyl group, ethylaminocarbonyl group, propylaminocarbonyl group, butylaminocarbonyl group, dimethylaminocarbonyl group, diethylaminicarbonyl group and diethanolaminocarbonyl group. A carbonyl group may be mentioned. The sulfonic acid amide group is not particularly limited, but the total carbon number is 20 or less, preferably 15 or less, and more specifically, aminosulfonyl group, methylaminosulfonyl group, ethylaminosulfonyl group, propylaminosulfonyl group. And alkylaminosulfonyl groups such as butylaminosulfonyl group, dimethylaminosulfonyl group, diethylaminosulfonyl group, diethanolaminosulfonyl group.

The alkylene group which may be substituted is not particularly limited, but the total number of carbon atoms is 20 or less, preferably 15 or less, and more specifically, -C _PH.
2P- (p represents an integer of 1 to 10) may be mentioned, and these may be substituted with a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, an amino group, a carboxyl group, a sulfonic acid group or the like. The phenylene group which may be substituted is not particularly limited, and examples thereof include an unsubstituted phenylene group, or a methyl group, an ethyl group, a methoxy group, an ethoxy group, fluorine, chlorine, bromine, iodine and the like. Examples thereof include an alkyl group or a phenylene group substituted with a halogen atom, a carboxyl group, a sulfonic acid group, a hydroxyl group, an amino group and the like. The xylylene group which may be substituted is not particularly limited, but, for example,
Unsubstituted xylylene group, or methyl group, ethyl group,
Alkoxy group such as methoxy group, ethoxy group, fluorine, chlorine, bromine, iodine or halogen atom, carboxyl group,
Examples thereof include a xylylene group substituted with a sulfonic acid group, a hydroxyl group, an amino group and the like. The naphthylene group which may be substituted is not particularly limited, and examples thereof include an unsubstituted naphthylene group, or a methyl group, an ethyl group, a methoxy group, an ethoxy group, fluorine, chlorine, bromine, iodine and the like. Examples thereof include an alkyl group or a naphthylene group substituted with a halogen atom, a carboxyl group, a sulfonic acid group, a hydroxyl group, an amino group and the like. The bonding position of the divalent linking group is not particularly limited. For example, in the phenylene group and the xylylene group which may be substituted, o-position, m-position, p-position
The naphthylene group which may be located at any position and may be substituted may be located at any position such as 1,5-position and 2,6-position.

The dyes represented by the general formula (A), the general formula (1), the general formula (C) and the general formula (4) used in the present invention are all in the form of a free acid or a salt. However, it may be used in any form.
Examples of the salt include alkali metal salts such as sodium, potassium and lithium, salts of alkyl or hydroxyalkyl ammonium, salts of organic amines such as ammonia, alkyl or hydroxyalkyl amine, carboxy substituted amine and the like. These may be used as a single salt, or may be used as a compound in which a plurality of salts are mixed, and a part thereof may remain in a free acid form. In addition, salt exchange may be appropriately performed if necessary.

As the dye represented by the general formula (A) and the dye represented by the general formula (1) used in the present invention, at least one of R ₁ and R ₃ is a halogen atom, and X is an alkylene group, a phenylene group, a xylylene group, a naphthylene group, or a divalent group represented by the general formula (2) (these connecting groups are halogen atoms, alkyl groups, alkoxy groups, hydroxyl groups, amino groups, carboxyl groups, sulfones) (May be substituted with an acid group)
Is what is. More preferably, R ₁ and R ₃ are both halogen atoms, and X is substituted with a phenylene group (halogen atom, alkyl group, alkoxy group, hydroxyl group, amino group, carboxyl group, sulfonic acid group) And A is a naphthyl group (the naphthyl group is a halogen atom, a hydroxyl group, an amino group, an optionally substituted alkyl group, an alkoxy group, a carboxyl group, a carboxylic acid ester group, a carboxylic acid amide group, It may be substituted with either a sulfonic acid group or a sulfonic acid amide group). Moisture resistance is improved when R ₁ and R ₃ are halogen atoms. The halogen atom of R ₁ and R ₃ may exist in a form substituted with OH, H and the like.

As the dye represented by the general formula (C) and the dye represented by the general formula (4) used in the present invention, at least one of R ₅ and R ₇ is a halogen atom, and X is an alkylene group which may be substituted, a phenylene group which may be substituted, a xylylene group, a naphthylene group which may be substituted, or a divalent linking group represented by the general formula (5) (these linking groups. The group is a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, an amino group, a carboxyl group or a sulfonic acid group). More preferably, R ₅ ,
Each of R ₇ is a halogen atom and X may be substituted with a phenylene group (which may be substituted with a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, an amino group, a carboxyl group or a sulfonic acid group). ), More preferably an unsubstituted phenylene group, and A may be substituted naphthyl group (the naphthyl group is a halogen atom, a hydroxyl group, an amino group, an optionally substituted alkyl group, an alkoxy group , A carboxyl group, a carboxylic acid ester group, a carboxylic acid amide group, a sulfonic acid group, or a sulfonic acid amide group), more preferably a naphthyl group having a sulfone group, particularly preferably the formula (B ):

[0022]

[Chemical formula 22] Is a dye represented by. When used as an ink, two or more dyes represented by the general formula (A) may be contained, and when two or more dyes are contained, one of them may be the dye of the formula (B). Especially preferred,
By mixing two or more kinds of dyes containing this, a delicate color tone can be created and high-quality ink jet printing can be performed. Specific examples of the dyes are shown in Table 1 (Tables 1 to 9), but the dyes are not limited to these.

[0023]

[Table 1]

[0024]

[Table 2]

[0025]

[Table 3]

[0026]

[Table 4]

[0027]

[Table 5]

[0028]

[Table 6]

[0029]

[Table 7]

[0030]

[Table 8]

[0031]

[Table 9]

The method of synthesizing the dye contained in the water-based ink of the present invention is not particularly limited, but an example is Yutaka Hosoda, "Theoretical Manufacturing Dye Chemistry Fifth Edition" (Showa 43).
It can be synthesized according to the method described in Gihodo Co., Ltd. on July 15, 2015. For example, No. 2 in Table 1
The dye (1) is added dropwise to a solution (pH 6 to 6.5) in which a sodium salt of H acid is dissolved in water, to cyanuric chloride dispersed in water at 0 to 2 ° C over 1 hour. The product is precipitated with sodium chloride. The precipitated product, sodium acetate, is added to water, and a solution of a diazotized product of 2-aminonaphthalene-1,5-disulfonic acid is added to perform azo coupling (coupling reaction is described in, for example, Yutaka Hosoda, "Theoretical Manufacturing Dyes"). It can be performed according to the method described in "Chemical 5th edition"). After the reaction, it is neutralized with a dilute solution of sodium carbonate to form a sodium salt, and sodium chloride is added to precipitate a monoazo dye. After filtration, the monoazo dye was dissolved in water, and 0.5 equivalent of a neutral aqueous solution of 1,3-diaminobenzene-6-sulfonate was added to the solution.
Add and react at 0-45 ° C. It is possible to synthesize the dye of No. 2 in Table 1 in the form of sodium salt by adding sodium chloride to cause precipitation.

The water-based ink of the present invention is useful as various inks, especially as a recording liquid for an ink jet recording system. The dye can be used as it is, but particularly when it is used as a recording liquid for an ink jet recording system, a raw material used for the synthesis of the dye, an intermediate or a by-product generated during the synthesis, or KCl, NaCl, Na. _In order to prevent clogging of the ejection nozzle portion of the recording apparatus due to impurities such as inorganic salts such as ₂ SO ₄ , it is preferable to remove or reduce these impurities. The removal and reduction of the impurities may be performed by, for example, an ion exchange resin, ultrafiltration or the like, but these methods have drawbacks such as a very long time, labor and cost. According to the method for producing a dye of the present invention, the synthesized dye is dissolved in water to form an aqueous solution, and then the pH is adjusted to 9 or more, preferably 10 or more, so that the dye contained in the dye is used for synthesis. The starting materials, impurities such as intermediates and by-products generated during the synthesis can be insolubilized and removed by filtration. At this time, it is more preferable to use a filter aid together in order to increase the removal efficiency. Further, the inorganic salt can be removed from the filtrate by mixing an aqueous solution of the dye with a water-soluble organic solvent to crystallize the dye and filtering. At this time, the dye may be dissolved in water and then the water-soluble organic solvent may be added, or the aqueous solution of the dye may be discharged into the water-soluble organic solvent for crystallization. Raw materials used for dye synthesis,
Either the step of removing intermediates or by-products generated during the synthesis or the step of removing the inorganic salt may be performed first, but the step of removing the inorganic salt is preferably performed later. The dye thus obtained preferably has no impurities precipitated at the pH when the ink is used, and the inorganic salt content is preferably 5% or less, more preferably 1% or less. It is particularly preferably 0.5% or less. As a result, it is possible to prevent clogging of the ejection nozzle portion of the ink produced using the dye.

The water used for the production of the dye and the ink is not particularly limited, but it is desirable that the amount of inorganic salts, inorganic ions and impurities is small, and filtered water, ion exchanged water, distilled water and the like are preferable. The amount of water used in dissolving the dye in water varies depending on the solubility of the dye and the content of the inorganic or organic substance, but is usually 1 to 10 parts by weight relative to 1 part by weight of the dye.
0 parts by weight. The temperature at the time of dissolution is usually room temperature, but when the dye has a high concentration or has low solubility, it can be dissolved by heating. The heating temperature in this case is preferably a temperature at which the dye does not decompose. For adjusting the pH, for example, acetic acid, hydrochloric acid, sulfuric acid, nitric acid, etc. are used as the acid, and sodium hydroxide, potassium hydroxide, aqueous ammonia, tetramethylammonium hydroxide, tetrabutylammonium hydroxide, etc. are used as the base. It is possible, but there is no particular problem with other things.

The filter aid to be used is not particularly limited, but examples thereof include diatomaceous earth, sawdust, asbestos, paper pulp, activated carbon, celite and talc. The amount of the water-soluble organic solvent used in the removal of the inorganic salt varies depending on the concentration of the dye aqueous solution, the solubility of the dye, the content of impurities in the dye, and the desired content of impurities in the dye after production. The amount is usually 1 to 100 parts by weight with respect to 1 part by weight of the dye, though it varies depending on the type. The water-soluble organic solvent is
It is preferable that the dye has low solubility, for example, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol,
Polyhydric alcohols such as polypropylene glycol, 1,3-propanediol, glycerin and thioglycol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, etc. Polyhydric alcohol ethers, ketones such as acetone and methyl ethyl ketone, amides such as N, N-dimethylformamide, N, N-diethylformamide and N, N-dimethylacetamide, 2-pyrrolidone, N-methyl-2-pyrrolidone , N-vinyl-2-pyrrolidone,
Nitrogen-containing compounds such as 1,3-dimethyl-2-imidazolidinone, ethers such as tetrahydrofuran and dioxane, methanol, ethanol, 1-propanol, 2-
Examples thereof include alcohols such as propanol, 1-butanol, 2-butanol and the like. Preferred are alcohols, polyhydric alcohols, and ketones. These water-soluble organic solvents may be used alone or in combination.
Further, when crystallizing the dye for removing the inorganic salt, if the crystallinity is low, it is possible to add an additive from the viewpoint of promoting crystallization within a range not deteriorating the performance of the dye after purification. .

The main component of the water-based ink of the present invention is a dye,
It is water and, if necessary, contains an organic solvent for the purpose of preventing the ink from drying and improving the solubility of the dye. The dyes represented by the general formula (A), the general formula (1), the general formula (C) or the general formula (4) may be used alone or in combination. The usage amount is
Depending on the type of dye, the ink composition, the printing density of the ink, and the content of impurities, the amount of dye is 0.
It is preferably from 5 to 20% by weight, particularly preferably from 1 to 10% by weight, and the organic solvent is preferably from 0 to 80% by weight. Further, in order to adjust the hue of the ink, and to improve other properties, other water-soluble dyes, or known dyes or pigments treated in an emulsion or finely dispersed state to the extent that the ink properties are not impaired May be added.

Examples of the water-soluble organic solvent contained in the water-based ink of the present invention include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, 1,3-propanediol, glycerin and thioglycol. Polyhydric alcohol ethers such as polyhydric alcohols, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, ketones such as acetone and methyl ethyl ketone,
Amides such as N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, 2-pyrrolidone, N-methyl-2-pyrrolidone, N
-Nitrogen-containing compounds such as vinyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidinone, ethers such as tetrahydrofuran and dioxane, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2- Examples thereof include alcohols such as butanol. These water-soluble organic solvents may be used alone or in combination, and the content is 0 to 80% by weight, preferably 5 to 5%.
Used in the range of 0% by weight. Further, the pH of the ink is preferably 8 or more in order to improve the ink characteristics (for example, water resistance). Further, in order to further improve the water resistance, it is preferable to use amines such as ammonia and hydroxyamines such as triethanolamine in combination. The content is preferably about 0.001 to 10% by weight with respect to the ink. Further, these amines may be used by forming a counter ion with a dye. Further, urea, thiourea, biuret, semicarbazide and their derivatives may be used in combination with the ink containing the dye of the present invention. The content is preferably about 0.1 to 15% by weight based on the water-based ink.

Various conventionally used additives can be added to the water-based ink of the present invention as needed. For example, ultraviolet absorber, antioxidant, chelating agent, water-soluble polymer, masking agent, antifungal agent, preservative, viscosity adjusting agent, surfactant, surface tension adjusting agent, pH adjusting agent, resistivity adjusting agent. , Near infrared absorbers, penetrants and other additives. The water-based ink of the present invention contains a dye,
It is manufactured by dissolving it with water, an organic solvent, and the above-mentioned additives as necessary. The water-based ink produced in this manner is used as an ink for writing instruments or the like, or as an ink for an inkjet recording method, recording characteristics, storage stability, fixability on a recording material, sharpness of a recorded image, light resistance, moisture resistance, etc. It is an excellent one. In particular, it is useful as a recording liquid for an ink jet recording system, but it is also used as an ink for writing tools such as ballpoint pens, felt pens, and fountain pens.

[0039]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples. In addition, "part" in an Example shows a weight part. Example 1 <Production of Dye> No. 1 in Table 1. 5 parts of 46 dyes were dissolved in 20 parts of distilled water. The aqueous dye solution was discharged into 10 parts of isopropyl alcohol to crystallize the dye, followed by filtration,
After drying, No. 1 in Table 1 was performed. 3 parts of a purified product of 46 dyestuffs are obtained. The analytical values of the dyes are shown below (Table 10). As a result, the content of inorganic salts such as NaCl was reduced, and the dye was usable by a simple production / purification process.

[Table 10] <Preparation of Ink> With the composition shown below, each compound was mixed and dissolved, and filtered through a Teflon (registered trademark) filter having a pore size of 0.45 micron to prepare an ink. <Ink composition> No. 1 in Table 1 after purification. Dye of 46 3 parts Diethylene glycol 30 parts N-methyl-2-pyrrolidone 10 parts Ion-exchanged water 57 parts <Characteristic evaluation> Using the ink prepared above, the ink cartridge for a piezo system inkjet printer was filled and the same system printer was used. Printing and image recording were performed, and tests were conducted on the following items. as a result,
(A) Image evaluation; A, (B) Moisture resistance evaluation; A, (C) Light resistance evaluation; A, (D) Ink storage stability evaluation; A,
(E) Evaluation of printer nozzle condition: Good. On the other hand, an ink was similarly prepared using a dye containing a large amount of inorganic salts before production, and the same evaluation was performed. As a result, (A) image evaluation; ○, (B) moisture resistance evaluation; ⊚, (C) light resistance evaluation; ⊚, (D) ink storage stability evaluation, Δ, (E) printer nozzle state evaluation; ×
Met. The ink containing the dye in which the inorganic salts are reduced by the simple manufacturing method of the present application was excellent in the storage stability of the ink and the ejection stability from the printer nozzle, especially when used in a recording liquid for inkjet. .

The evaluation criteria for each test item are as follows. (A) Image evaluation An image was formed on plain paper, and the bleeding state was visually determined. [Evaluation Criteria] No bleeding and no problem; ◎ Some bleeding is observed, but the image is not affected; ◯ Bleeding is noticeable; × (B) Moisture resistance evaluation The condition of the recorded image after standing for a certain period of time under the conditions was visually evaluated for moisture resistance. [Evaluation Criteria] No change in image after left for 48 hours; ◎ No change in image after left for 24 hours, bleeding of dye at edge of recorded image after left for 48 hours, ○ ○ After left for 24 hours Dye bleeding at the edge; × (C) Evaluation of light resistance Using a xenon fade meter (manufactured by Suga Test Instruments Co., Ltd.)
The print density (OD value) before irradiation and after irradiation for 100 hours was measured using a reflection densitometer (manufactured by Macbeth Co.), and the OD was compared to evaluate light resistance. OD = (OD value after irradiation) / (OD value before irradiation) × 10
0 (%) [Evaluation Criteria] OD is 100% to 80% or more; ◎ OD is less than 80% to 70% or more; OD is less than 70% to 50% or more; △ OD is less than 50%; X (D) Evaluation of storage stability of ink The state of the ink after storage at 40 ° C was visually observed. [Evaluation Criteria] No insoluble matter after 3 months; ◎ No insoluble matter after 1 month, no insoluble matter after 3 months, but no problem in use; ○ One insoluble matter after 1 month, no problem in use, After 3 months, there is a problem with the use of insoluble matter; △ After 1 month, there is a problem with the use of insoluble matter; × (E) Printer nozzle condition evaluation Visually check the condition of the nozzle after printing with a piezo inkjet printer. I observed it. [Evaluation Criteria] No abnormality; ○ Adherents are seen, but there is no problem in use; △ Adherents are present; ×

Example 2 <Production of Dye> No. 1 in Table 1. 5 parts of 30 dyes were dissolved in 20 parts of distilled water. Acetone 10 to this dye aqueous solution
Part was added dropwise to crystallize the dye, followed by filtration and drying. 3 parts of a purified product of 30 dyes are obtained. The analytical values of the dyes are shown below (Table 11). As a result, the content of inorganic salts such as NaCl was reduced, and the dye was usable by a simple production / purification process.

[Table 11] <Preparation of Ink> Ink was prepared by mixing and dissolving each compound with the composition shown below and filtering through a membrane filter having a pore size of 0.45 micron. <Ink composition> No. 1 in Table 1 after purification. Dye of 30 3 parts Triethylamine 1 part Diethylene glycol 30 parts N-Methyl-2-pyrrolidone 10 parts Ion-exchanged water 56 parts <Evaluation of properties> The above inks were used to evaluate the properties by the method described in Example 1. As a result, (A) image evaluation;
◎, (B) Moisture resistance evaluation; ◎, (C) Light resistance evaluation; ◎,
(D) Storage stability evaluation of ink; ◯; (E) Evaluation of printer nozzle state; On the contrary,
An ink was similarly prepared using a dye containing a large amount of inorganic salts before production, and the same evaluation was performed. as a result,
(A) Image evaluation: ◯, (B) Moisture resistance evaluation: ⊚, (C) Light resistance evaluation: ⊚, (D) Ink storage stability evaluation: Δ,
(E) State evaluation of printer nozzle: Poor. The ink containing the dye in which the inorganic salts are reduced by the simple manufacturing method of the present application was excellent in the storage stability of the ink and the ejection stability from the printer nozzle, especially when used in a recording liquid for inkjet. .

Examples 3 to 37 Dyes and inks were prepared by the method described in Example 1 using the dyes shown in Table 1. The results are shown in Table 2.

[Table 12]

Example 38 <Production of Dye> No. 1 in Table 1. 5 parts of 46 dyes were dissolved in 20 parts of distilled water. This 10% aqueous solution of sodium hydroxide was added to the aqueous dye solution with stirring until the pH reached 10. After stirring for 1 hour, 2 parts of activated carbon was added, and the mixture was further stirred for 1 hour. After that, No. The mixture was filtered through 5C filter paper, the filtrate was discharged into 10 parts of isopropyl alcohol, the dye was crystallized, filtered and dried. Four
3 parts of a purified product of 6 are obtained. The analytical values of the dyes are shown below (Table 13). As a result, the content of inorganic salts such as NaCl is reduced, and the raw materials used for the dye synthesis, impurities such as intermediates and by-products generated during the synthesis are removed, and a simple production / purification process is performed. It became a usable dye.

[0044]

[Table 13] <Preparation of Ink> Ink was prepared by mixing and dissolving each compound with the composition shown below and filtering through a Teflon filter having a pore size of 0.45 micron. <Ink composition> No. 1 in Table 1 after purification. Dye of 46 3 parts Diethylene glycol 30 parts N-methyl-2-pyrrolidone 10 parts Ion-exchanged water 57 parts <Evaluation of characteristics> The above-mentioned inks were used to evaluate the characteristics by the method described in Example 1. As a result, (A) image evaluation;
◎, (B) Moisture resistance evaluation; ◎, (C) Light resistance evaluation; ◎,
(D) Evaluation of storage stability of ink: ⊚, (E) Evaluation of printer nozzle state; On the contrary,
An ink was similarly prepared using a dye containing a large amount of raw materials, intermediates, by-products, and inorganic salts before production, and evaluated in the same manner. As a result, (A) image evaluation; ○, (B) moisture resistance evaluation; ⊚, (C) light resistance evaluation; ⊚, (D) ink storage stability evaluation, Δ, (E) printer nozzle state evaluation; It was x. The ink containing a dye produced by the simple production method of the present application was excellent in storage stability of the ink and ejection stability from a printer nozzle, especially when used in a recording liquid for inkjet.

Example 39 <Production of Dye> No. 1 in Table 1 5 parts of 46 dyes were dissolved in 20 parts of distilled water. This 10% aqueous solution of sodium hydroxide was added to the aqueous dye solution with stirring until the pH reached 10. After stirring for 1 hour, 2 parts of Celite was added, and the mixture was further stirred for 1 hour. After that, No. Filter with 5C filter paper, discharge the filtrate to 10 parts of isopropyl alcohol,
The dye was crystallized, filtered and dried.
3 parts of a purified product of 46 dyestuffs are obtained. The analytical values of the dyes are shown below (Table 14). As a result, the content of inorganic salts such as NaCl is reduced, and the raw materials used for the dye synthesis, impurities such as intermediates and by-products generated during the synthesis are removed,
It became a dye that can be used by a simple manufacturing and purification process.

[Table 14] <Preparation of Ink> Ink was prepared by mixing and dissolving each compound with the composition shown below and filtering through a Teflon filter having a pore size of 0.45 micron. <Ink composition> No. 1 in Table 1 after purification. Dye of 46 3 parts Diethylene glycol 30 parts N-methyl-2-pyrrolidone 10 parts Ion-exchanged water 57 parts <Evaluation of characteristics> The above-mentioned inks were used to evaluate the characteristics by the method described in Example 1. As a result, (A) image evaluation;
◎, (B) Moisture resistance evaluation; ◎, (C) Light resistance evaluation; ◎,
(D) Evaluation of storage stability of ink: ⊚, (E) Evaluation of printer nozzle state; On the contrary,
An ink was similarly prepared using a dye containing a large amount of raw materials, intermediates, by-products, and inorganic salts before production, and evaluated in the same manner. As a result, (A) image evaluation; ○, (B) moisture resistance evaluation; ⊚, (C) light resistance evaluation; ⊚, (D) ink storage stability evaluation, Δ, (E) printer nozzle state evaluation; It was x. The ink containing a dye produced by the simple production method of the present application was excellent in storage stability of the ink and ejection stability from a printer nozzle, especially when used in a recording liquid for inkjet.

Example 40 <Production of Dye> No. 1 in Table 1 5 parts of 30 dyes were dissolved in 20 parts of distilled water. This 10% aqueous solution of sodium hydroxide was added to the aqueous dye solution with stirring until the pH reached 10. After stirring for 1 hour, add 2 parts of diatomaceous earth,
It was stirred for another hour. After that, No. After filtering with a 5C filter paper, 10 parts of acetone was added dropwise to the filtrate to crystallize the dye, followed by filtration and drying. 3 parts of a purified product of 30 dyes are obtained. The analytical values of the dyes are shown below (Table 15). As a result, the content of inorganic salts such as NaCl is reduced, and the raw materials used for the dye synthesis, impurities such as intermediates and by-products generated during the synthesis are removed, and a simple manufacturing / purification process is performed. It became a usable dye.

[0047]

[Table 15] <Preparation of Ink> Ink was prepared by mixing and dissolving each compound with the composition shown below and filtering through a membrane filter having a pore size of 0.45 micron. <Ink composition> No. 1 in Table 1 after purification. Dye of 30 3 parts Triethylamine 1 part Diethylene glycol 30 parts N-Methyl-2-pyrrolidone 10 parts Ion-exchanged water 56 parts <Evaluation of properties> The above inks were used to evaluate the properties by the method described in Example 1. As a result, (A) image evaluation;
◎, (B) Moisture resistance evaluation; ◎, (C) Light resistance evaluation; ◎,
(D) Evaluation of storage stability of ink: ⊚, (E) Evaluation of printer nozzle state; On the contrary,
An ink was similarly prepared using a dye containing a large amount of raw materials, intermediates, by-products, and inorganic salts before production, and evaluated in the same manner. As a result, (A) image evaluation; ○, (B) moisture resistance evaluation; ⊚, (C) light resistance evaluation; ⊚, (D) ink storage stability evaluation, Δ, (E) printer nozzle state evaluation; It was x. The ink containing a dye produced by the simple production method of the present application was excellent in storage stability of the ink and ejection stability from a printer nozzle, especially when used in a recording liquid for inkjet.

Example 41 <Production of Dye> No. 1 in Table 1 5 parts of 30 dyes were dissolved in 20 parts of distilled water. This 10% aqueous solution of sodium hydroxide was added to the aqueous dye solution with stirring until the pH reached 10. After stirring for 1 hour, add 2 parts of diatomaceous earth,
It was stirred for another hour. After that, No. Filtration was performed with 5C filter paper to obtain a dye aqueous solution having a concentration of about 20%. As a result, the raw materials used in the synthesis of the dye, impurities such as intermediates and by-products generated during the synthesis were removed, and the dye was usable by a simple production / purification process. <Preparation of Ink> Ink was prepared by mixing and dissolving each compound with the composition shown below and filtering through a membrane filter having a pore size of 0.45 micron. <Ink composition> No. 1 in Table 1 after purification. 20% aqueous solution of 30 15 parts Triethylamine 1 part Diethylene glycol 30 parts N-methyl-2-pyrrolidone 10 parts Ion-exchanged water 44 parts <Evaluation of characteristics> The characteristics of the inks were evaluated by the method described in Example 1. It was As a result, (A) image evaluation;
◎, (B) Moisture resistance evaluation; ◎, (C) Light resistance evaluation; ◎,
(D) Storage stability evaluation of ink; ◯; (E) Evaluation of printer nozzle state; On the contrary,
An ink was similarly prepared using a dye containing a large amount of raw materials, intermediates, by-products, and inorganic salts before production, and evaluated in the same manner. As a result, (A) image evaluation; ○, (B) moisture resistance evaluation; ⊚, (C) light resistance evaluation; ⊚, (D) ink storage stability evaluation, Δ, (E) printer nozzle state evaluation; It was x. The ink containing a dye produced by the simple production method of the present application was excellent in storage stability of the ink and ejection stability from a printer nozzle, especially when used in a recording liquid for inkjet.

Examples 42 to 70 Dyes and inks were prepared by the method described in Example 38 using the dyes shown in Table 1. The results are shown in Table 3 (Table 16).

[Table 16]

Example 71 <Preparation of Ink> No. 1 in Table 1 after purification produced in Example 1 46 dyes and the purified 1st prepared in Example 2
No. in the table Using the dyes of No. 30, each compound was mixed and dissolved in the composition shown below, and filtered through a Teflon filter having a pore size of 0.45 micron to prepare an ink. <Ink composition> No. 1 in Table 1 after purification. Dye of 46, 1.5 parts No. 1 in Table 1 after purification. Dye of 30 1.5 parts Diethylene glycol 30 parts N-methyl-2-pyrrolidone 10 parts Ion-exchanged water 57 parts <Evaluation of characteristics> Using the above-mentioned inks by the method described in Example 1, the characteristics were evaluated. As a result, (A) image evaluation;
◎, (B) Moisture resistance evaluation; ◎, (C) Light resistance evaluation; ◎,
(D) Storage stability evaluation of ink; ◯; (E) Evaluation of printer nozzle state; On the contrary,
No. 1 in Table 1 before purification containing a large amount of inorganic salts before production. 30 and No. Inks were prepared using the dyes mixed in the same composition as above except that the dyes of 46 were used, and the same evaluation was performed. As a result, (A) image evaluation;
○, (B) Moisture resistance evaluation; ◎, (C) Light resistance evaluation; ◎,
(D) Storage stability evaluation of ink: Δ, (E) Printer nozzle state evaluation: ×. It should be noted that the ink containing the dye in which the inorganic salts are reduced by the simple production method of the present invention is excellent in the storage stability of the ink and the ejection stability from the printer nozzle, especially when used in a recording liquid for inkjet. It was When the color tone was evaluated according to JIS Z-8729, No. 1 in Table 1 was evaluated. 30 or No.
All had slightly different color tones compared to the inks consisting of 46 dyes.

Example 72 <Preparation of Ink> No. 1 in Table 1 after purification prepared in Example 39. No. 46 in Table 1 after the dyestuff prepared in Example 40 and the dyestuff of Example 46. Using the dyes of No. 30, each compound was mixed and dissolved in the composition shown below, and filtered through a Teflon filter having a pore size of 0.45 micron to prepare an ink. <Ink composition> No. 1 in Table 1 after purification. Dye of 46, 1.5 parts No. 1 in Table 1 after purification. Dye of 30 1.5 parts Diethylene glycol 30 parts N-methyl-2-pyrrolidone 10 parts Ion-exchanged water 57 parts <Evaluation of characteristics> Using the above-mentioned inks by the method described in Example 1, the characteristics were evaluated. As a result, (A) image evaluation;
◎, (B) Moisture resistance evaluation; ◎, (C) Light resistance evaluation; ◎,
(D) Evaluation of storage stability of ink: ⊚, (E) Evaluation of printer nozzle state; On the contrary,
No. 1 in Table 1 before purification containing a large amount of inorganic salts before production. 30 and No. Ink was prepared using a dye mixed with the same composition as above except that the dye of 46 was used, and the same evaluation was performed. As a result, (A) image evaluation; ◯, (B) moisture resistance evaluation; ⊚, (C) light resistance evaluation;
⊚, (D) Ink storage stability evaluation: Δ, (E) Printer nozzle state evaluation: ×. The ink containing the dye produced by the simple production method of the present invention was excellent in the storage stability of the ink and the ejection stability from the printer nozzle, particularly when used in a recording liquid for inkjet. When the color tone was evaluated according to JIS Z-8729, No. 1 in Table 1 was evaluated. 46 or No. All had slightly different color tones compared to the inks consisting of 30 dyes.

Comparative Example 1 <Production of Dye by Organic Solvent> No. 1 in Table 1 The dye of No. 46 was used, and the dye was dissolved in an organic solvent, which is a method for removing inorganic salts, to produce inorganic salts. N in Table 1
o. 5 parts of 46 dyes with 5 parts of N, N-dimethylformamide 5
Although 0 part was added, the dye was not dissolved, and the dispersed state was filtered off and dried. The following (Table 17) shows the analytical values of the dyes. As a result, the content of inorganic salts such as NaCl cannot be reduced, and the raw materials used for dye synthesis, impurities such as intermediates and by-products generated during the synthesis cannot be reduced, and the present invention is simple and easy. It could not be manufactured by the manufacturing method.

[Table 17] Further, a dissolution test was conducted using other organic solvents, but it did not dissolve as in the case of using N, N-dimethylformamide. This is because the dye has a high water-solubility, but has a property of having little solubility in an organic solvent. Therefore, the dye is dissolved in an organic solvent which is a general method,
No method of removing inorganic salts was possible.

Comparative Example 2 <Production of Dye by Organic Solvent> Dye 5 represented by the formula (d)
50 parts of N, N-dimethylformamide was added and dissolved. The insoluble matter was filtered off and dried. As a result, 2 parts of a dye purified with an organic solvent was obtained. Below (Table 18)
The analytical value of the dye is shown. As a result, the content of inorganic salts such as NaCl was reduced.

[Chemical formula 23] (D)

[Table 18] Using 5 parts of the dye of the formula (d) after purification produced as described above, an ink was prepared according to the method for preparing the ink of Example 1, and the characteristics were evaluated in the same manner. As a result, (A) image evaluation;
(B) Moisture resistance evaluation ×, (C) Light resistance evaluation; Δ, (D) Ink storage stability evaluation; ○, (E) Printer nozzle state evaluation; Δ, which is significantly higher than the water-based ink of the present invention. It was bad.

[0054]

The water-based ink containing the dye produced by the simple production method of the present invention exhibits excellent light resistance, moisture resistance and storage stability. When used as a recording liquid for an inkjet recording method, it is important to suppress the content of inorganic salts as much as possible and to reduce impurities such as intermediates and by-products generated during the synthesis. It can be achieved simply and effectively by the manufacturing method. as a result,
It is possible to provide a water-based ink that does not cause clogging of the printer head, enables high-quality and bleeding-free image formation, and has excellent light resistance, moisture resistance, and storage stability for recorded images.

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hiroshi Naruse 580-32 Nagaura, Sodegaura-shi, Chiba Mitsui Chemicals Co., Ltd. (72) Denmi Misawa 580-32 Nagaura, Sodegaura-shi, Chiba Mitsui Chemicals (56 ) Reference JP-A-10-114877 (JP, A) JP-A-10-114878 (JP, A) JP-A-10-114879 (JP, A) JP-A-10-114880 (JP, A) JP-A-10-114880 (JP, A) 10-315612 (JP, A) JP 10-176129 (JP, A) JP 11-58944 (JP, A) JP 9-12949 (JP, A) JP 9-12950 (JP, A) JP-A-6-191138 (JP, A) JP-A-61-101574 (JP, A) JP-A-2000-178463 (JP, A) JP-A-2000-297222 (JP, A) JP-A-8-505889 (JP, A) International publication 00/15723 (WO, A1) (58) Fields investigated (Int.Cl. ⁷ , D B name) C09D 11/00-11/20 C09B 67/54 CA (STN) REGISTRY (STN)

Claims (4)

(57) [Claims] 1. An aqueous ink containing a dye and an aqueous medium as main components, which is represented by the formula (B) as a dye.
An aqueous ink for ink jet recording containing a dye or a salt thereof . [Chemical 1] 2. A dye represented by the formula (B) according to claim 1.
Or the salt is dissolved in water and the pH of the aqueous solution is raised to 9 or more.
Incorporating a dye from which insoluble matter produced by adjustment has been removed
The water system for ink jet recording according to claim 1.
ink. 3. A dye represented by the formula (B) according to claim 1.
Or its salt is dissolved in water to form an aqueous solution
Contains a dye that is crystallized by mixing with an organic solvent
The ink jet recording according to claim 1, wherein
Water-based ink. 4. A dye represented by formula (B) according to claim 1.
Or the salt is dissolved in water and the pH of the aqueous solution is raised to 9 or more.
The aqueous solution from which the insoluble matter generated by adjustment is removed is water-soluble.
Contains a dye that is crystallized by mixing with an organic solvent.
The water for inkjet recording according to claim 1,
System ink.