JPH06157957A - Recording liquid - Google Patents

Abstract

PURPOSE:To obtain a recording liquid comprising a water-based medium and specific black dye, useful for ink jet recording and writing utensils, capable of giving highly dense recording printed images good in print quality when recorded on sheets of plain paper, also excellent in resistance to light, etc. CONSTITUTION:This recording liquid comprises (A) a water-based medium and (B) pref. 2-5wt.%, based on the whole recording liquid, of a black dye of the formula (A is phenyl or naphthyl; B is phenylene or naphthylene; R is H, alkyl, etc.; M is Na, Li, etc.). The component A is pref. composed of water and a water-soluble organic solvent such as ethylene glycol, and it is recommended that the water accounts for 45-95wt.% of the whole recording liquid. For further improving quick dryability and print quality after printing, it is preferable that 0.5-5wt.% of urea or buret be added to the recording liquid.

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 a recording liquid droplet containing a water-soluble dye such as a direct dye or an acid dye is ejected from a minute ejection orifice to perform recording. Regarding this recording, in addition to being capable of stable ejection for a long time, it is commonly used for general office work such as PPC (plain paper copier) paper such as electrophotographic paper and fan hold paper (continuous paper such as computers). Fast fixing to recording paper and good print quality of printed matter, that is, print without blurring and clear contour, are required, and stability during storage as recording liquid is also excellent. Therefore, the solvent that can be used for the recording liquid is extremely limited.

On the other hand, the dye for the recording liquid has a sufficient solubility in the limited solvent as described above, which enables stable ejection for a long time as the recording liquid.
It is stable even when stored for a long time, the density of the printed image is high, and it has excellent water resistance and light resistance. In addition, it is easy to manufacture, and there is no safety problem. However, it was difficult to satisfy many of these requirements at the same time.

Therefore, various methods (for example, JP-A-55-55)
144067, JP-A-55-152747, JP-A-57-207660, JP-A-58-147470,
JP-A-62-190269, JP-A-62-19027
1, JP-A-62-190272, JP-A-62-25
0082, JP-A-62-246975, JP-A-62.
-257971, JP-A-62-288659, JP-A-63-8463, JP-A-63-22867, JP-A-63-22874, JP-A-63-30567, JP-A-63-33484. No. 63-63764,
JP-A-63-105079, JP-A-64-31877
JP-A-1-93389, JP-A-1-210464
JP-A-2-140270 and JP-A-3-16727.
No. 0 and Japanese Patent Laid-Open No. 3-200882) have been proposed, but in addition to satisfying the market requirements in terms of performance,
It has not been possible to develop a dye that is easy to manufacture.

[0005]

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, which is excellent in water resistance and light resistance. It is an object of the present invention to provide a black recording liquid which is excellent in stability and has good stability when stored for a long period of time.

[0006]

The present inventor has accomplished the present invention by confirming that the above object is achieved when a specific black dye is used as a recording liquid component. That is, the gist of the present invention resides in a recording liquid containing an aqueous medium and at least one of the dyes represented by the general formula (I) in claim 1.

The present invention will be described in detail below. The dye used in the present invention is represented by the general formula (I) in claim 1. In the general formula (I), the substituents of the phenyl group, naphthyl group, phenylene group or naphthylene group represented by A and B include -SO ₃ M group and -COOM group (M in the general formula (I). M has the same meaning as M), amino group, acylamino group (eg, lower alkylcarbonylamino group such as acetylamino group, propionylamino group, arylcarbonylamino group such as benzoylamino group, etc.), linear or branched chain A C 1-4 alkoxy group, a hydroxyl group, a halogen atom such as a chlorine atom, a bromine atom and a fluorine atom, and a linear or branched C 1-4 alkyl group, and the like. You may have more than one. Examples of R in the formula (I) include, in addition to a hydrogen atom, a linear or branched alkyl group having 1 to 8 carbon atoms, or a linear or branched C 1 to 4 carbon atom. A hydroxyalkyl group, a linear or branched C1-C4 alkyl group substituted with a -COOM group, a linear or branched C1-C8 alkoxyalkyl group and a lower alkyl group, Examples thereof include a lower alkoxy group, an acylamino group, a carboxyl group, a halogen atom, and a phenyl group which may be substituted with a hydroxy group.

M in formula (I) represents the salt form of the dye. Specific examples of these dyes include dyes having the structures shown in Table 1 below (lithium salt type) and dyes whose salt type is Na salt type, ammonium salt type, or organic amine salt type. Can be mentioned. The organic amine salt is a salt of a mono-, di- or tri-substituted amine, and examples thereof include a lower alkyl amine salt, a hydroxy substituted lower alkyl amine salt, a carboxy substituted lower alkyl amine salt and a carbon number 2
Examples thereof include salts of polyamines having 2 to 10 alkyleneimine units of 4 to 4 and the like.

[0009]

[Table 1]

[0010]

[Table 2]

[0011]

[Table 3]

[0012]

[Table 4]

[0013]

[Table 5]

[0014]

[Table 6]

[0015]

[Table 7]

[0016]

[Table 8]

[0017]

[Table 9]

[0018]

[Table 10]

The azo dye represented by the formula (I) can be prepared by a method known per se {for example, "New dye chemistry" by Yutaka Hosoda (Showa 4).
It can be manufactured through a diazotization and a coupling process according to December 1988, published by Gihodo, pp. 396-409. The content of the dye of formula (I) in the recording liquid is preferably 0.5 to 8% by weight, more preferably 2 to 5% by weight, based on the total amount of the recording liquid.

When the dye of the present invention is used in a recording liquid, it may be used alone or in a mixture of two or more kinds. As the solvent used in the recording liquid of the present invention, water and water-soluble organic solvents such as ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol,
Polyethylene glycol (# 200, # 400), glycerin, α-pyrrolidone, N-methylpyrrolidone, N-
Ethylpyrrolidone, 1,3-dimethylimidazolidinone, ethylene glycol monoallyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene Glycol dipropyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, dimethyl sulfoxide, bis (β-hydroxyethyl) thioether, dimethylformamide, diethanolamine, trieta Ruamin, isopropanol,
It preferably contains ethanol, methanol 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 used in the range of 45 to 95% by weight with respect to the total amount of the recording liquid.

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, burette, and semicarbazide, or by adding 0.001 to 5% by weight of a surfactant, the quick-drying property after printing and the printing quality can be further improved. .

[0022]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples unless it exceeds the gist.

Example 1 Composition of recording liquid

[0024]

[Table 11]

The above components were sufficiently mixed and dissolved, filtered under pressure 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, an inkjet printer (HG-3000, manufactured by Epson Corporation) was used to perform inkjet recording on electrophotographic paper (manufactured by Fuji Xerox Co., Ltd.) to obtain a black recorded matter with high color density. . In addition, the results of various evaluations by the following methods (a), (b) and (c) are shown.

(A) Lightfastness of recorded image The recorded matter was irradiated for 100 hours using a xenon fade meter (manufactured by Suga Test Instruments Co., Ltd.), but the discoloration and fading after irradiation was small.

(B) Water resistance of recorded image The bleeding of the image was examined after the recorded matter was immersed in water for 5 minutes. The bleeding of the image was slight and the decrease in density was small. Further, when the recorded matter was sprinkled with 10 ml of water and allowed to stand, there was no bleeding and no white field contamination was observed.

(C) Storage stability of recording liquid The recording liquid was sealed in a Teflon container and kept at 5 ° C. and 60 ° C. for 1 hour.
The change in the recording liquid after the storage for a month was examined, but there was no change in the recording liquid.

Example 2 Composition of recording liquid

[0030]

[Table 12]

The above components were treated by the method described in Example 1 to prepare a recording liquid.
Various evaluations of (c) were performed. As a result, good results were obtained as in the case of Example 1.

Example 3 Composition of recording liquid

[0033]

[Table 13]

The above components were treated by the method described in Example 1 to prepare a recording liquid.
Various evaluations of (c) were performed. As a result, good results were obtained as in the case of Example 1.

Examples 4 to 18 Instead of the dye of No. 1 used in Example 1, No. 2, No. 3, No. 10, No. 18, No. 19, N.
o.20, No.21, No.22, No.23, No.24, N
A recording liquid was prepared by the method of Example 1 except that the dyes of No. 25, No. 26, No. 27, No. 28, and No. 29 were used, respectively. Various evaluations of (c) were performed. As a result, good results were obtained as in the case of Example 1.

Examples 19 to 27 Instead of the (No. 1) dye (lithium salt type) used in Example 2, the above No. 3, No. 10, No. 21,
No.23, No.24, No.25, No.27, No.28,
A recording liquid was prepared by the method of Example 2 except that an ammonium salt type dye having the same structure as the dye of No. 29 was used and the salt type was the same as that of (a) to (c). Various evaluations were performed. As a result, good results were obtained as in the case of Example 2.

The recording liquid of the present invention is used for ink jet recording and writing instruments, and when recorded on plain paper,
It is possible to obtain a recorded matter having a high print quality and a high color density, and in addition to excellent light resistance and water resistance of a recorded image, storage stability of a recording liquid is also good.

Claims (1)

[Claims] 1. A recording liquid containing an aqueous medium and at least one dye represented by the following general formula (I). [Chemical 1] (In the formula, A represents a phenyl group or a naphthyl group, which may have a substituent, B represents a phenylene group or a naphthylene group, which may have a substituent, and R represents hydrogen. Atom, optionally substituted alkyl group,
Or an optionally substituted phenyl group, M is Na, Li, an ammonium group or an organic amine salt, and n is 0 or 1.)