JP3274551B2 - Color lead core 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 ink for impregnating a firing type color lead core, and more particularly to an ink for impregnating a small diameter color lead core used in a mechanical pencil or the like.

[0002]

2. Description of the Related Art Conventionally, a kneaded material containing a body material such as boron nitride and a binder such as clay as a main component and an organic polymer compound added thereto is extruded and then fired at a high temperature to obtain a white core. It is already known to impregnate the pores with a dye ink to form a colored lead.

[0003] However, this type of color lead core is incompatible with strength and color density, and if the porosity of the porous core is increased to increase the amount of ink impregnated, the color density is improved, but the strength is inevitably reduced. Conversely, if the porosity of the porous core is reduced to ensure strength, the amount of ink impregnation decreases, resulting in an extreme decrease in color density, which is not suitable for practical use. Therefore, in order to improve the color density, a non-volatile solvent having high solubility of the dye is used.

[0004]

However, when the color lead is impregnated with the ink, the ink in the pores is in direct contact with the outside air, so that there is a problem over time. This is not only a non-volatile solvent or a solvent that dissolves and disperses a large amount of dye, but it is also desirable that the viscosity and tint of the solvent do not change over a long period of time, and as a result, the color tone and handwriting of the handwriting are retained It is connected to things. In this sense, if the solvent used in the conventional ink for color lead cores is exposed to the open air for a long period of time, the viscosity and tint will change, and as a result, the color tone and writing taste of the color lead core will deteriorate. is there.

[0005]

According to the present invention, a specific compound is used as a solvent for dissolving or dispersing a coloring substance, whereby the coloring property and the sharpness of the coloring substance are significantly improved without deterioration due to aging. It is an object of the present invention to provide a color lead core ink having an improved width.

The present invention is characterized by using polyoxyethylene alkyl phenyl ether as a solvent in a lead color ink from the above viewpoint, and its structural formula is shown in Chemical Formula 1.

[0007]

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Here, R is an alkyl group having 1 or more carbon atoms,
n is 2 or more, and examples thereof include polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, and polyoxyethylene dodecyl phenyl ether.

In the present invention, it is preferable to use polyoxyethylene alkyl phenyl ether in an amount of at least 45% (by weight) of the total solvent, and other solvents may be used in combination. It is. The higher the amount, the better the ink with less deterioration over time.

[0010] Solvents that can be used in combination include conventionally used solvents such as oleic acid. The coloring substance used is preferably a basic dye, an oil-soluble dye, or a spirit-soluble dye. And processed pigments can also be used.

The color lead core used in the present invention may be a conventionally known calcined color lead core, and may include a body material such as boron nitride or talc and a binder such as clay, and, if necessary, a pigment or an organic polymer compound. Is extruded, and the porous core obtained by firing at a high temperature is used, and the pores are impregnated with the ink using the solvent of the present invention.

[0012]

【Example】

Example 1 To 65 parts of polyoxyethylene nonylphenyl ether heated to 70 ° C., 35 parts of Spiron Red C-GH (manufactured by Hodogaya Chemical) was added, and the mixture was sufficiently stirred while maintaining the temperature.
After filtration, a red ink was obtained.

Example 2 75 parts of polyoxyethylene octyl phenyl ether 25 parts of Victoria Pure Blue Base (manufactured by BASF) A blue ink was obtained in the same manner as in Example 1.

Example 3 Polyoxyethylene dodecylphenyl ether 45 parts Oleic acid 20 parts Oil orange 201 (manufactured by Orient Chemical) 35 parts An orange ink was obtained in the same manner as in Example 1.

Comparative Example 1 In Example 1, except that polyoxyethylene nonylphenyl ether was replaced with sorbitan sesquiolate.
A red ink was obtained in the same manner as in Example 1.

Comparative Example 2 A red ink was obtained in the same manner as in Example 1 except that polyoxyethylene nonylphenyl ether was replaced with polyoxyethylene monostearate.

Comparative Example 3 A red ink was obtained in the same manner as in Example 1, except that glyceryl monocaprylate was used instead of polyoxyethylene nonylphenyl ether.

As described above, a white core made of boron nitride and clay was immersed in the ink obtained in each example, and heated at 70 ° C. for 10 hours. Next, the excess ink adhering to the surface of the white core impregnated with the ink was washed with an organic solvent and dried at 50 ° C. for 12 hours to obtain a lead core of each color. Here, the color lead cores impregnated with the inks of Examples 1 and 2 are particularly preferable because the solvent of the present invention is used at 100%, and there is almost no deterioration over time in color tone and writing taste for a long period of time.

[0019]

The lead cores using the lead ink of the present invention show clear handwriting and smooth writing.
Erasability with the eraser was also good. Further, the colored lead cores impregnated with the inks of the respective examples were left in a blow dryer at 60 ° C. for 60 days, and were taken out and examined for their state and writing quality. The crystals of the dye precipitated on the surface, making it difficult to feed out with a mechanical pencil, and the handwriting became thin and the writing taste became hard. On the other hand, the colored lead cores obtained in Examples 1, 2, and 3 had appearance, handwriting,
There was no change in writing taste. As described above, the color lead core impregnated with the ink of the present invention has excellent characteristics that the change over time is small and the initial performance can be maintained for a long time.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C09D 13/00

Claims (1)

(57) [Claims] 1. A color lead core ink which is impregnated into pores of a porous core obtained by firing at a high temperature, wherein polyoxyethylene alkylphenyl ether is used as a solvent for dissolving or dispersing a coloring substance in an amount of 45% of the total solvent. A color lead core ink characterized by being used as described above.