JP3033293B2 - Recording liquid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording liquid. More specifically, the present invention 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 to practical use in which recording is performed by flying droplets of a recording liquid containing a water-soluble dye such as a direct dye or an acid dye from a minute discharge orifice. As for the solvent of the recording liquid, fixing to recording paper generally used for general office work such as PPC (plain paper copier) paper such as electrophotographic paper and fan hold paper (continuous paper such as a computer) is fast, and printed matter is also high. It is required that the print quality of the ink is good, that is, the print is required to have a clear outline without bleeding, and to have excellent stability during storage as a recording liquid, and thus can be used. Solvents are severely restricted.

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 time.
Further, it is required that the density of the printed image is high, and that it is excellent in water resistance and light resistance. However, it has been difficult to satisfy many of these requirements at the same time. Therefore, various methods (for example, JP-A-55-1440065, JP-A-57-30773, JP-A-57-207660,
JP-A-58-147470, JP-A-62-19026
9, JP-A-62-190271, JP-A-62-19
No. 0272, JP-A-62-250082 and JP-A-62-1982
JP-A-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
JP-A-63-63764, JP-A-63-1050
No. 79, JP-A-64-31877, JP-A-1-933
No. 89, JP-A-1-210464, JP-A-2-140
No. 270) has been proposed, but has not yet been able to sufficiently satisfy the market requirements.

[0004]

SUMMARY OF THE INVENTION According to the present invention, a recording liquid containing a specific dye is used for ink jet recording, writing, etc., so that the print quality can be improved even when recording on plain paper. It is an object of the present invention to provide a recording liquid having a high density of a recorded image, excellent light fastness, and particularly excellent water fastness, and having good stability when stored for a long period of time.

[0005]

Means for Solving the Problems The present inventors have confirmed that the above objects can be achieved when a specific dye is used as a recording liquid component, and have achieved the present invention. 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. Hereinafter, the present invention will be described in detail. In the general formula [I], the alkali metal represented by M is N.
a, K, Li, etc., and examples of the organic amine salt include three or four hydrogen atoms of an ammonium group having an alkyl group having 1 to 4 carbon atoms and / or
And a group substituted with a hydroxyalkyl group.
Specific examples of these dyes include, for example,
An azo dye having the structure shown in (i) is mentioned.

[0006]

Embedded image

[0007]

Embedded image

The recording liquid of the present invention is characterized by containing at least one dye as described above. The azo dye represented by the general formula [I] can be diazotized according to a method known per se [for example, see Yushin Hosoda, “Shin Dye Chemistry” (published by Gihodo on December 21, 1973, pp. 396-409)). , Through a coupling step. The content of the dye of the general formula [I] in the recording liquid is 0.5 to 5% by weight based on the total amount of the recording liquid.
Particularly, about 2 to 4% by weight is preferable. As the solvent used in the recording liquid of the present invention, as water and a water-soluble organic solvent,
For example, ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (# 200),
Polyethylene glycol (# 400), glycerin, N
-Methyl-pyrrolidone, N-ethyl-pyrrolidone, 1,
It preferably contains 3-dimethyl-imidazolidinone, ethylene glycol monoallyl ether, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether and the like. These water-soluble organic solvents are usually used in an amount of 10 to 50% by weight based on the total amount of the recording liquid. On the other hand, water is 45-45% of the total amount of recording paper.
It is used in the range of 89.5% by weight.

In the recording liquid of the present invention, 0.1% of the total amount is used.
1 to 10% by weight, preferably 0.5 to 5% by weight of urea,
By adding a compound selected from thiourea, biuret, and semicarbazide, and by adding 0.001 to 5.0% by weight of a surfactant, it is possible to further improve the quick-drying property after printing and the print quality. it can.

[0010]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which, however, are not intended to limit the scope of the invention. Example 1 25 parts by weight of ethylene glycol monoallyl ether, 22 parts by weight of ethylene glycol, dye of the above formula (a)
Water was added to 5 parts by weight to adjust the total amount to 100 parts by weight. This composition was sufficiently mixed and dissolved to give a pore size of 1 μm.
After filtration under pressure through a Teflon filter of m, the recording liquid was prepared by deaeration using a vacuum pump and an ultrasonic cleaner. Using the obtained recording liquid, ink jet recording was performed on electrophotographic paper (manufactured by Fuji Xerox) using an ink jet printer (trade name: HG-3000, manufactured by Epson Corporation), and the following (a), (b) and ( The result of performing various evaluations by the method c) is shown. (A) Light fastness of recorded image: Recording paper was irradiated for 100 hours using a Canon Fade Meter (manufactured by Suga Test Instruments Co., Ltd.). Discoloration after irradiation was small.

(B) Water resistance of the recorded image: The bleeding of the image after immersing the recording paper in water for 24 hours was examined. The bleeding of the image was slight, and the decrease in density was small.

(C) Storage stability of the recording solution: The recording solution was sealed in a Teflon container, and the change after storage at 5 ° C. and 60 ° C. for one month was examined. No precipitation of insolubles was observed. Example 2 Water was added to 10 parts by weight of glycerin, 10 parts by weight of ethylene glycol, and 5 parts by weight of the dye of the formula (b) to make the total amount 1
The composition was treated by the method described in Example 1 to prepare a recording liquid, and the recording liquid was prepared.
Various evaluations according to (c) were performed. As a result, good results were obtained in all cases as in Example 1.

EXAMPLE 3 Water was added to 5 parts by weight of diethylene glycol monobutyl ether, 15 parts by weight of glycerin, and 2 parts by weight of the dye of the formula (c) to make the total amount 100 parts by weight. This composition was described in Example 1. The recording liquid was prepared by the method described above, and various evaluations according to (a) to (c) of Example 1 were performed. As a result, similar to Example 1, good results were obtained.

Examples 4 to 9 The procedure of Example 1 was repeated except that the dyes of the formulas (d) to (l) were used instead of the dye of the formula (a) used in the example 1. A recording liquid was prepared, and various evaluations in (a) to (c) of Example 1 were performed. As a result, similar to Example 1, good results were obtained.

[0015]

The recording liquid of the present invention is used for ink-jet recording and writing instruments, and is excellent in print density, light resistance and water resistance of a recorded image when recorded on plain paper. As well as storage stability.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C09D 11/00-11/20 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] 1. A recording liquid comprising an aqueous medium and at least one dye selected from dyes represented by the following general formula [I]. Embedded image (Wherein R ¹ and R ² each represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a hydroxyalkyl group having 2 to 4 carbon atoms substituted with a COOM group, and X and Y represent a hydrogen atom and methyl, respectively. And m represents 0 or 1 or 2, n represents 0 or 1, and M represents an alkali metal, ammonium group or a group of an organic amine salt.