JP3225422B2 - Water-based ink - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aqueous ink using a basic dye. More specifically, the present invention relates to an aqueous ink using a basic dye which exhibits excellent stability even after long-term storage without precipitation or discoloration over time.

[0002]

2. Description of the Related Art Conventionally, water-soluble inks such as acid dyes, direct dyes and basic dyes are often used as colorants in aqueous inks. In particular, basic dyes are known to have advantages such as sharpness of color or dark color per weight unit as compared with the acid dyes and direct dyes (for example, Japanese Patent Publication No. -22314). In the case of water-based inks, for the purpose of stabilizing with time, prevention of formalin, sodium salts of pentachlorophenol, alkylphenols, thiazoles, pyridines, benzoimidals, morpholines, and the like is required. Addition of fungicides has been performed. Further, in the aqueous ink, a high-boiling water-soluble organic solvent as a dye dissolution aid or an antifreezing agent, and various additives such as a water-soluble polymer and a surfactant depending on the intended use are also used. .

[0003]

An aqueous ink using a basic dye as a dye has a problem that the dye precipitates or discolors when stored for a long period of time. This is considered to be due to the influence of components other than the dye used in the aqueous ink. An object of the present invention is to provide a water-based ink which solves this problem and has excellent stability even when stored for a long time.

[0004]

According to the present invention, there is provided a mixture of a basic dye, 2-chloroacetamide and sodium fluoride.
A compound or 2-bromo-2-nitropropanediol;
The gist is an aqueous ink containing at least water.

The details will be described below. Basic dyes are used as coloring materials. An example is described below. C. I. Basic Yellow-1, 2 and 21, C.I. I. Basic Orange 2, 14, 32 and C.I. I. Basic Red 1, 2, 9, 14, C.I. I. Basic violet 1, 3, 7, 10, C.I. I. Basic Green-3, 26, Basic Green 4, C.I. I. Basic Brown 12, C.I. I. Basic Black 2, 8 and the like. These dyes can be used alone or in combination. It is preferable to use 0.01 to 20% by weight based on the total amount of the aqueous ink.

[0006] 2-Chloroacetamide and sodium fluoride
Or 2-bromo-2-nitropropanedioxide
- le are those used for preventing and has a good effect as a fungicide, after long-term storage or precipitation dye also, that the ink is discolored. These compounds can be used singly or as a mixture of two or more kinds.
It is preferable to add 2% by weight.

[0007] Water is used as the main solvent. It is preferable to use 30 to 90% by weight based on the total amount of the aqueous ink.

[0008] In addition to the above essential components, if necessary, a fluorescent dye such as polyethylene glycol, a fluorescent color improver, a glycol solvent such as ethylene glycol, diethylene glycol, triethylene glycol or thiodiglycol, and a glycerin are used. A high-boiling water-soluble organic solvent, a water-soluble polymer, a surfactant, a rust inhibitor, a pen tip drying inhibitor such as urea, ethylene urea, and thiourea may be appropriately selected and used.

[0009]

Water-based ink according to the present invention, a basic dye, 2
A mixture of chloroacetamide and sodium fluoride or
Contains 2-bromo-2-nitropropanediol . This compound keeps the pH of the aqueous ink acidic,
It prevents the functional groups in the basic dye molecule from reacting, prevents precipitation of the dye and discoloration of the ink, and has good antiseptic and antifungal effects. Therefore, it is presumed that the present ink prevents spoilage and mold generation of the ink even when stored for a long period of time, and exhibits excellent stability.

[0010]

EXAMPLES Examples and comparative examples will be described below.

Embodiment 1 The above components are stirred and mixed using a stirrer to obtain a yellow ink.
Was.

Embodiment 2 Stir and mix each of the above components using a stirrer to create a fluorescent pink ink
I got

Comparative Example 1 In Example 1, 2-bromo-2-nitropropanediol was used.
1,2-benzisothiazoline-3-o
Except that a yellowing agent (fungicide) was used.
A color ink was obtained.

Comparative Example 2 In Example 1, 2-bromo-2-nitropropanedio
-Sunbuck P-50 (preservative, thiazo-
Example except for using a compound based on a compound (manufactured by Sanai Sekiyu KK)
In the same manner as in Example 1, a yellow ink was obtained.

Obtained in Examples 1 and 2 and Comparative Examples 1 and 2
Presence or absence of dye precipitation after long-term storage of aqueous ink
A mildew test was conducted. Also, using this water-based ink,
Writing instruments using water-based ink sold (Pentel Signal S51)
0, manufactured by Pentel Co., Ltd.)
The test was performed for nothing. Table 1 shows the test results.

[0016]

[Table 1]

(Presence or absence of precipitation) The aqueous ink was sealed in a glass bottle, and two bottles were placed in a 50 ° C. thermostat.
After standing for a month, the presence or absence of dye precipitation was visually confirmed. ：: No precipitation ×: Precipitation (presence or absence of discoloration) Immediately after assembling the above writing instrument, test using this writing instrument.
Coat the test paper. Put this writing instrument in a 50 ° C
After standing for a month, the test paper is surface-coated in the same manner as described above. This neglect
Measure the color tone of the test paper coated on the front and back, and
Calculate the color tone difference (color difference ΔE, unit: NBS) of the cloth surface,
The degree of discoloration was evaluated. The larger the value of color difference, the more
Indicates a high degree. Note that the color tone is
Data SM-4 (manufactured by Suga Test Instruments Co., Ltd.) was used. ( Mold resistance test) Based on JIS Z 2911 (Test method for mold resistance)
And the antifungal effect was confirmed. ○: Antifungal effect ×: No antifungal effect

[0018]

As described in detail above, the present invention
Aqueous inks use basic dyes as dyes.
Despite being stored for long periods of time,
Does not occur, as well as precipitation of dye and discoloration of ink.
And has an effect of exhibiting excellent stability.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-55173 (JP, A) JP-A-61-272277 (JP, A) JP-A-5-32951 (JP, A) 316880 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09D 11/00-11/20 A01N 33/18 A01N 37/18 A01N 59/10 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] 1. A basic dye and 2-chloroacetamide
Mixture of sodium and sodium fluoride or 2-bromo-2-ni
An aqueous ink containing at least troppropanediol and water.