JPH0790211A - Recording solution - Google Patents

Abstract

PURPOSE:To obtain the recording solution useful for ink-jet recording and writing tools, having magenta color, excellent printing concentration, light resistance, water resistance and shelf stability, containing an aqueous medium and a monoazo-based coloring matter having a specific free acid type. CONSTITUTION:This recording solution contains (A) an aqueous medium of water and a water-soluble organic solvent (e.g. ethylene glycol or glycerol) and (B) at least one coloring matter selected from coloring matters having a free acid type of formula I [R1, R2 and R3 are 1-9C (substituted) alkyl, 1-9C alkoxy, halogen, H, hydroxyl, etc.; (m) is 0, 1 or 2; R4, R5, R6 and R7 are H, 1-18C alkyl, 1-18C alkenyl, aryl, etc., with the proviso that at least one of R4 to R7 contains COOH group as a substituent group] such as a coloring matter of formula II. The recording solution preferably contains 45-95wt.% of water, 1-50wt.% of the water-soluble organic solvent and 0.5-5wt.%, especially 2-4wt.% of the coloring matter of the component B.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a recording liquid. Specifically, it relates to a recording liquid suitable for inkjet recording.

[0002]

2. Description of the Related Art A so-called ink jet recording method has been put into practical use in which droplets of a recording liquid containing a water-soluble dye such as a direct dye or an acid dye are ejected from a minute ejection orifice to perform recording. Regarding this recording liquid, P of electrophotographic paper is used.
Fast fixing to general-purpose office-use recording paper such as PC (plain paper copier) paper and fan-hold paper (continuous paper for computers etc.) and good print quality, that is, print bleeding It is required to have a clear outline and to have excellent stability during storage as a recording liquid.
Therefore, the solvent that can be used is extremely limited.

On the other hand, dyes for recording liquids have sufficient solubility in the above-mentioned limited solvents and are stable even when stored as recording liquids for a long period of time.
Further, although it is required that the printed image has a high density and is excellent in water resistance and light resistance, it has been difficult to satisfy many of these requirements at the same time. Therefore, various methods (for example, JP-A-61-101574, JP-A-61-101576, JP-A-61-195176) are used.
No. 61-62562, JP-A 61-2477.
71, JP-A-62-156168, JP-A-63-6.
3765, JP-A-63-295685, JP-A-1-
123866, JP-A-2-16171, JP-A-3-
122171, JP-A-3-203970, JP-A-4
No. 15327, JP-A No. 4-279671, etc.) have been proposed, but they have not yet fully satisfied the market demands.

[0004]

DISCLOSURE OF THE INVENTION The present invention has good print quality even when recorded on plain paper for ink jet recording, writing instruments, etc., and has a high density of recorded images, light resistance and It is an object of the present invention to provide a magenta recording liquid which is excellent in water resistance and color tone of a recorded image and has good stability when stored for a long period of time.

[0005]

The present inventors have accomplished the present invention by confirming that the above objects can be achieved when a specific dye is used as a recording liquid component. That is, the gist of the present invention lies in a recording liquid containing an aqueous medium and at least one monoazo dye whose free acid form is represented by the general formula {1} in claim 1.

The present invention will be described in detail below. The dye used in the present invention is a monoazo dye whose free acid form is represented by the general formula {1} in claim 1. Specifically, in the general formula {1}, the substituents represented by R ₁ , R ₂ and R ₃ are each independently a substituted or unsubstituted alkyl group having 1 to 9 carbon atoms (eg, methyl group, ethyl group). Group, n-propyl group, isopropyl group, n-butyl group, trifluoromethyl group, dimethylaminomethyl group, etc.), alkoxy group having 1 to 9 carbon atoms (eg, methoxy group, isopropoxy group, n-butoxy group, etc.) ), A halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, etc.),
Hydrogen atom, hydroxyl group, substituted or unsubstituted carbamoyl group (eg, carbamoyl group, N, N-dimethylcarbamoyl group, phenylcarbamoyl group, etc.), substituted or unsubstituted sulfamoyl group (eg, sulfamoyl group, N-methylsulfyl group) Famoyl group, N-ethylsulfamoyl group, N-ethyl-N-phenylsulfamoyl group, N, N-dimethylsulfamoyl group, p-carboxyphenylsulfamoyl group, etc.), substituted or unsubstituted Amino group (for example, N-methylamino group, carbamoylamino group, N, N-diethylamino group, acetylamino group, etc.), nitro group, sulfonate group (for example, phenoxysulfonyl group, etc.), sulfonyl group (for example, hydroxyethyl) Sulfonyl group, benzylsulfonyl group, etc.), COOH group and Carboxylic acid ester group (e.g., methoxy carbonyloxy group, etc.).

M represents 0, 1 or 2. R ₄ , R ₅ ,
The substituents represented by R ₆ and R ₇ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms (eg, ethyl group, n-butyl group, n-octyl group, Ethylhexyl group, hydroxyethyl group, carboxypropyl group, carboxycyclohexylmethyl group, 1-carboxy-2-mercaptoethyl group, 1-carboxy-2-carbamoyl-ethyl group, 1-isopropyl-1-carboxymethyl group, 1,2 -An alkyl group having a carboxyl group such as a dicarboxypropyl group), a substituted or unsubstituted alkenyl group having 1 to 18 carbon atoms (e.g., 2-methyl-1-propenyl group, vinyl group, allyl group, etc.), substituted Alternatively, an unsubstituted aryl group (eg, 3,4-dicarboxyphenyl group, 4-butylphenyl group, 4-carboyl group) A phenyl group), a substituted or unsubstituted aralkyl group (eg, a benzyl group, 1
-Carboxy-2-phenyl-ethyl group, 1-carboxy-2-hydroxyphenylethyl group, 4-carboxybenzyl group, etc.), a substituted or unsubstituted alicyclic group (eg, cyclohexyl group, 4-carboxycyclohexyl group, etc.) ), And a substituted or unsubstituted heterocyclic group (eg, pyridyl group, thiadiazolyl group, benzothiazolyl group, 2,2,6,6-tetramethylpiperidinyl group, etc.). However, R ₄ , R ₅ , R ₆
At least one of R ₇ and R ₇ represents a group having a COOH group (carboxyl group) as a substituent.

More preferably R ₄ , R ₅ , R ₆ or R ₇
An alkyl group, an alkenyl group, an aryl group, an aralkyl group, or a cyclohexyl group, at least one of which is substituted with 1 to 4 COOH groups. The dye used in the present invention may be used as it is in the free acid form represented by the general formula {1}, or may be used as it is when it is obtained in the salt form at the time of production, or may be in the desired salt form. May be converted to
A part of the acid group may be a salt type, and a salt type dye and a free acid type dye may be mixed. Examples of such salt type are salts of alkali metals such as Na, Li, K,
Examples thereof include ammonium salts which may be substituted with an alkyl group or a hydroxyalkyl group, and organic amine salts. Examples of organic amines include lower alkylamines, hydroxy-substituted lower alkylamines, carboxy-substituted lower alkylamines, and polyamines having 2 to 10 alkyleneimine units having 2 to 4 carbon atoms. In the case of these salt types, the type is not limited to one type, and a plurality of types may be mixed.

In the structure of the dye used in the present invention, when one molecule contains a plurality of acid groups, the plurality of acid groups are salt type or free acid type and are the same or different from each other. May be Specific examples of these dyes include, for example, Nos. Examples thereof include dyes having the structures shown in 1-62.

[0010]

[Chemical 2]

[0011]

[Chemical 3]

[0012]

[Chemical 4]

[0013]

[Chemical 5]

[0014]

[Chemical 6]

[0015]

[Chemical 7]

[0016]

[Chemical 8]

[0017]

[Chemical 9]

[0018]

[Chemical 10]

[0019]

[Chemical 11]

[0020]

[Chemical 12]

[0021]

[Chemical 13]

[0022]

[Chemical 14]

[0023]

[Chemical 15]

[0024]

[Chemical 16]

The azo dye represented by the general formula {1} can be produced by a method known per se. For example, No. The dye represented by (1) can be produced by the following steps (A) to (C). (A) A conventional method from 4-aminotoluene-3-sulfonic acid and 1-amino-8-hydroxy-3,6-naphthalenedisulfonic acid (H acid) [eg Yutaka Hosoda "New Dye Chemistry"]
(Published by Gihodo on December 21, 1973) 396-40
Page 9], a monoazo compound is produced through the diazotization and coupling steps. (B) The obtained monoazo compound is added to a cyanuric chloride suspension while maintaining pH 4 to 6 and temperature 0 to 5 ° C, and the reaction is carried out for several hours. Then, at room temperature, a β-alanine aqueous solution is added so as not to become alkaline, and a condensation reaction is performed for several hours. Next, the n-butylamine solution is added at 50 to 60 ° C. to complete the condensation reaction for several hours to complete the reaction. (C) After cooling, salting out with 20% saline was performed to obtain the desired dye No. (1) is obtained.

The content of the dye of the general formula {1} in the recording liquid is preferably 0.5 to 5% by weight, particularly preferably 2 to 4% by weight, based on the total amount of the recording liquid. Examples of the solvent used in the present invention include water and water-soluble organic solvents such as ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (# 200), polyethylene glycol (# 400), glycerin, and N. -Methylpyrrolidone, N-ethylpyrrolidone, 1,3-dimethylimidazolidinone, thiodiethanol, dimethylsulfoxide, ethylene glycol monoallyl ether,
It preferably contains ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, 2-pyrrolidone, sulfolane, ethyl alcohol, isopropanol and the like. These water-soluble organic solvents are usually used in the range of 1 to 50% by weight based on the total amount of the recording liquid. On the other hand, water is 45 to 95% by weight with respect to the total amount of recording liquid
Used in the range of.

The recording liquid of the present invention contains 0.
1-10 wt% urea, preferably 0.5-5 wt% urea,
By adding a compound selected from thiourea, biuret, and semicarbazide, or by adding 0.001 to 5.0% by weight of a surfactant, the quick-drying property after printing and the printing quality can be further improved. it can.

[0028]

EXAMPLES The present invention will now be described in more detail with reference to examples, but the present invention is not limited to these examples as long as the gist thereof is not exceeded. Example 1 10 parts by weight of diethylene glycol, 3 parts by weight of isopropyl alcohol, No. Water was added to 3 parts by weight of dye 1 and the pH was adjusted to 9 with aqueous ammonia to make the total amount 100 parts by weight. The composition was thoroughly mixed and dissolved, pressure-filtered with a Teflon filter having a pore size of 1 μm, and then deaerated with a vacuum pump and an ultrasonic cleaner to prepare a recording liquid.

Using the obtained recording liquid, ink jet recording was carried out on electrophotographic paper (neutral paper, Xerox Co.) using an ink jet printer (trade name HG-3000, manufactured by Epson Co.) to obtain a high density magenta. Colored prints were obtained. The results of various evaluations by the methods (a), (b) and (c) are shown below. (A) Light resistance of recorded image: The recording paper was irradiated with a xenon fade meter (manufactured by Suga Test Instruments Co., Ltd.) for 100 hours, but the discoloration and fading after irradiation was small. (B) Water resistance of recorded image: Water resistance test (1) Test method After the recorded image was immersed in tap water for 5 minutes, the bleeding of the image was visually examined.

The OD value of the solid printed portion before and after the immersion was measured with a Macbeth densitometer (TR927). (2) Test result The above-mentioned result image was slightly blurred. The change in the density of the solid printed portion before and after the immersion described above was 84.7% as shown by the OD residual ratio according to the following formula.

[0031]

[Formula 1] OD residual rate = (OD value after immersion / OD value before immersion)
× 100 (%) (c) Storage stability of recording liquid: When the recording liquid was sealed in a Teflon container and stored at 5 ° C. and 60 ° C. for 1 month, the change was examined and precipitation of insoluble matter was observed. There wasn't. Example 2 5 parts by weight of glycerin, 10 parts by weight of ethylene glycol, No. Water was added to 25 parts by weight of the dye of No. 8 and the pH was adjusted to 9 with ammonia water so that the total amount was 100 parts by weight. This composition was treated by the method described in Example 1 to prepare a recording liquid. Printing was performed in the same manner as in Example 1 using this recording liquid, and as a result, a high density magenta color recorded product was obtained. Further, for this recorded matter, (a) to
Various evaluations according to (c) were performed. As a result, good results were obtained as in the case of Example 1.

The OD residual rate was 86.5%. [Example 3] 10 parts by weight of diethylene glycol, 5 parts by weight of N-methylpyrrolidone, 3 parts by weight of isopropyl alcohol, Water was added to 3 parts by weight of the 24 dye, and the pH was adjusted to 9 with aqueous ammonia to adjust the total amount to 100 parts by weight, and this composition was treated by the method described in Example 1 to prepare a recording liquid. Printing was performed in the same manner as in Example 1 using this recording liquid, and as a result, a high density magenta color recorded product was obtained. Further, with respect to this recorded matter, (a) to (c) of Example 1
Various evaluations were performed. As a result, good results were obtained as in the case of Example 1.

The OD residual rate was 85.2%. [Examples 4 to 34] In Example 1, the No. Instead of the dye of No. 1, 2-7, No. 9-23, N
o. A recording liquid was prepared and printing was performed by the method of Example 1 except that the dyes of 25 to 34 were used, and various evaluations according to (a) to (c) of Example 1 were performed on the recorded matter. It was As a result, as in Example 1, good results were obtained. In addition, dye No. The residual OD of the recording liquid using No. 2 was 86.3%, and the dye No. It was 88.4% in the recording liquid using No. 3. [Examples 35 to 41] 12 parts by weight of thiodiglycol, N
-Methyl-2-pyrrolidone 4 parts by weight, 2-propanol 3 parts by weight, the above-mentioned No. 41, 43, 44, 45, 46,
Water was added to 3 parts by weight of the dye of 47 or 62, and the pH was adjusted to 9 with aqueous ammonia to adjust the total amount to 100 parts by weight. The composition was thoroughly mixed and dissolved, pressure-filtered with a Teflon filter having a pore size of 1 μm, and then deaerated with a vacuum pump and an ultrasonic cleaner to prepare a recording liquid.

Using the obtained recording liquid, ink jet recording was carried out on an electrophotographic paper (neutral paper, manufactured by Xerox Co., Ltd.) using an ink jet printer (trade name: HG-3000, manufactured by Epson Corp.) to obtain high density magenta. Colored prints were obtained. The following table shows the results of various evaluations by the methods (a), (b), (c) and (d) below. (A) Physical properties of recording liquid (dye solubility): The recording liquid was filtered using a Teflon filter of 0.45 μm, and the solubility of the dye was determined by visually determining the presence or absence of a filtration residue. The symbol ⊚ in the table indicates that the solubility of the dye is extremely good by visual judgment. (B) Color tone of recorded image: Solid printing is performed by the above printing machine using the above recording liquid, and the color tone of that portion is measured by a color difference system (product of Nippon Denshoku Co., Ltd.). (C) Density of recorded image: Solid printing is performed with the above printing machine using the above recording liquid, and the color density of the portion is measured with a microdensitometer (Macbeth TR927). (D) Water resistance of recorded image: a. 5-minute immersion test The above recording liquid was used to perform solid printing with the printing machine described above, and the test piece was allowed to stand at room temperature and normal humidity for one day.
After soaking for a minute, the OD residual rate was calculated from the OD values before and after the test by the following formula.

[0035]

[Formula 2] OD residual rate = (OD value after immersion / OD value before immersion)
× 100 (%) a. 5 second immersion test (ground stain): The above recording liquid was printed by the above printing machine, left for one day at room temperature and normal humidity, and the test piece was immersed in tap water for 5 seconds to remove the background stain. Determine the degree visually. In the table, ⊚ indicates that image bleeding, change in color density, and change in color tone are very slight by visual judgment, and ○ is slightly inferior to ⊚ in visual judgment, but practically no problem. It shows that it is good.

[0036]

[Table 1]

[0037]

INDUSTRIAL APPLICABILITY The recording liquid of the present invention is used for ink jet recording and writing instruments, and when recorded on plain paper, a magenta color recorded matter can be obtained, and its printing density, light resistance and water resistance are excellent. In addition to excellent properties, it also has good storage stability as a recording liquid.

Claims (1)

[Claims] 1. An aqueous medium and a free acid form are represented by the following general formula:
At least one color selected from the dyes represented by {1}
A recording liquid containing an element. [Chemical 1](In the formula, R₁, R₂And R₃Are each independently carbon
Substituted or unsubstituted alkyl group having 1 to 9 carbon atoms
~ 9 alkoxy groups, halogen atoms, hydrogen atoms, hydro
Xyl group, substituted or unsubstituted carbamoyl group, substituted
Or an unsubstituted sulfamoyl group, a substituted or non-substituted
Substitute amino group, nitro group, sulfonate group,
Ruphonyl group, COOH group, or carboxylic acid ester
Represents a group of, m represents a number of 0, 1 or 2, R_Four, R_Five, R₆And R₇Are independently hydrogen
Child, an alkyl group having 1 to 18 carbon atoms, an alkyl group having 1 to 18 carbon atoms
Lucenyl group, aryl group, aralkyl group, alicycle
Represents a heterocyclic group or a heterocyclic group, and these
Of those other than hydrogen atom, it has a substituent
Good. However, R_Four, R_Five, R₆And R ₇At least
One represents a group having a COOH group as a substituent. )