JPS59217770A - Erasing material for colorless dye-developer based ink - Google Patents

Abstract

PURPOSE:The titled erasing material, obtained by dissolving a nonvolatile desensitizer in a mixed solvent of a low-boiling solvent and a high-boiling solvent mutually forming no azeotropic mixture, preventing the drying of the tip of a pen and weight loss due to permeation through the axial cylinder during the lapse of a long time, and capable of rewriting in a short time. CONSTITUTION:An erasing material obtained by dissolving (A) a nonvolatile densesitizer, e.g. diphenyl phthalate, containing (i) a developer and (ii) a colorless dye in (B) a mixed solvent prepared by incorporating (i) a low-boiling solvent, e.g. methyl acetate, which is a good solvent for a coloring ink and has <=120 deg.C boiling point with (ii) a high-boiling solvent, e.g. ethyl alcohol, which is a poor solvent for the coloring ink and has a higher boiling point than the component (i) preferably at (5:95)-(40:60) weight ratio.

Description

Detailed Description of the Invention The present invention relates to a color developer having a phenolic hydroxyl group and a colorless electron-donating organic compound (
The present invention relates to an erasing material for erasing handwriting made with an ink (hereinafter referred to as colorless dye-developer ink) consisting of a colorless dye (hereinafter referred to as colorless dye) and a solvent that severely inhibits color development reaction.

Colorless dye-color developer ink contains a colorless dye that is colored by a color developer, and because it is darkly colored like normal oil-based ink, it can produce dark and clear handwriting. It also has the advantage that it can be easily erased using a polar compound that has a desensitizing effect. That is, it is believed that the color-forming complex or cus produced by the reaction between the color developer and the colorless dye base is decomposed by the desensitizing effect of the polar compound, and as a result becomes completely colorless.

A patent application has already been filed by the same applicant for the erasing material for colorless dye-developer ink (Japanese Patent Application No. 1983).
-11999). This erasing material consists of a solution of a desensitizing organic compound with a melting point of 60°C or higher and a vapor pressure of 1 mmHg or lower at 150°C dissolved in a solvent with a boiling point of 16°C or lower. Since we use a non-volatile desensitizing organic compound that is solid at room temperature and can erase ink, but once the solvent evaporates, it solidifies and loses its desensitizing effect. This has the advantage that even if you write again on the erased surface with the same ink within about 6 minutes, the handwriting will not become colorless again.

However, from a practical standpoint, rewriting in a shorter time is strongly desired. To do this, it is best to use a solvent with a lower boiling point than the solvent for the eraser, but if such a low boiling point solvent is used, the nib of the eraser may dry out easily or it may become long. When a period of time passes, disadvantages such as increased loss of solvent permeation through the barrel of the eraser occur, which is undesirable from a practical point of view.

Therefore, the present invention has been developed as a result of intensive research aimed at providing a practical erasing material that can solve the above-mentioned drawbacks and can be rewritten in a short period of time. a low boiling point solvent that is a good solvent for the color forming ink and has a boiling point of 120'C or less; It was discovered that by using a mixed solvent consisting of a high-boiling point solvent that does not boil, an ink erasing material without the above-mentioned drawbacks can be obtained.
This completes the present invention. That is, the present invention provides a colorless dye-developer system prepared by dissolving in a solvent a nonvolatile desensitizer that makes color-forming ink colorless, which contains a color developer and a colorless dye developed by the color developer. In the ink erasing material, a low boiling point solvent which is a good solvent for the colored ink and has a boiling point of 120'c or less is used as a solvent for the erasing material, and a low boiling point solvent which is a poor solvent for the colored ink and has a boiling point of 120'c or less. The object of the present invention is to provide an erasing material for colorless dye-developer ink, which is characterized by using a mixed solvent consisting of a high boiling point solvent and a high boiling point solvent that does not azeotrope with the low boiling point solvent.

Examples of non-volatile desensitizers that can be used in the present invention include EVA, diphenyl phthalate, diphenyl urethane, pentaerythritol tetraacetate, pentaerythritol tetrabenzoate, diphenyl glycolic acid, ethylene glycol dibenzoate, N-phenyl-β-nanthylamine, N -7-enyl anthranilic acid phenyl ester, N-phenylanthranilic acid methyl ester, benzoguanamine, 4,4'-methylenebis(cetanilide), 4,4'-sulfonylbis(acetanilide),
p-aminoacetanilide, benzacetin, 4-butoxy-N-hydroxybenzeneacetamide, 2.3-
Dihydro-2,2-dimethyl-7-benzofuranol methyl carbamate, cotoine, diaminodiphenylmethane, dianisidine, 4-(enylmethylphenol)carbamate, galactitol, diphenyl phthalate, 4'-(methylsulfamoyl)-sulfanyl Anilide, 4,4'-tetramethyldiaminodiphenylmethane, polyvinylpyrrolidone, polyvinyl acetate, N-
Vinylpyrrolidone-vinyl acetate copolymer,
Examples include oligo-N-methylmolporinium propylene oxide, 5-fat, poly-N-butoxymethylacrylamide, and vinyl acetate-maleic acid copolymer.

Any solvent that can dissolve the above-mentioned nonvolatile desensitizers that are solid at room temperature can be used as a solvent, but in the present invention,
From the viewpoint of rewriting on the erased surface, the solvent is particularly a low boiling point solvent that is a good solvent for the coloring ink and has a boiling point of 120°C or less, and a low boiling point solvent that is a poor solvent for the coloring ink and has a boiling point of 120°C or less. A mixed solvent consisting of a high boiling point solvent that has a higher boiling point than the solvent and does not azeotrope with the low boiling point solvent is used. In this case, the low boiling point solvent has a strong ability to dissolve handwriting, so the ink and desensitizer At the same time, the amount of the low boiling point solvent in the erasing material is smaller than that of a low boiling point solvent alone, so it evaporates quickly and completely eliminates the erased traces. Even if it is not dry, only the high boiling point solvent remains compared to the coloring ink, so even if you write again with the same coloring ink, the dissolving power for the handwriting is weak, and therefore the coloring ink and desensitization will be mixed. Handwriting is often erased because it is difficult to react with the agent. That is, it becomes possible to rewrite in a short time. In addition, since the mixed solvent of the low boiling point bath agent and the high boiling point solvent is used as the solvent for the erasing material, the weight loss due to drying of the pen tip of the eraser 12 and permeation through the barrel of the eraser after a long period of time is reduced. This can be prevented as much as possible.

As the low boiling point solvent, those that are good solvents for the coloring ink and have a boiling point of 120°C or less can be used, such as esters such as methyl acetate, ethyl acetate, n-propyl acetate, isopropyl 61' acid, and isopropyl ether. , ethers such as tetrahydrofuran, dioxane, and tetrahydrobilane, and ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone.

As the high boiling point solvent, those that are poor solvents for the coloring ink, have a higher boiling point than the low boiling point solvents, and do not azeotrope with the low boiling point solvents can be used, such as Eva, ethyl alcohol, water, isopropyl alcohol. , n-butyl alcohol, 1.1.1-trichloroethane, trichlene, toluene, xylene, methylcyclohexane, ethylbenzene, and the like.

As a mixed solvent, a combination of a low boiling point solvent and a high boiling point solvent that has a boiling point higher than the low boiling point solvent and does not azeotrope among the combinations of the low boiling point solvent and the high boiling point solvent can be used. Combinations such as imran-ethyl alcohol, tetrahydro-7-isobrobyl alcohol, dioxane-methyl cellosolve, ethyl acetate-toluene, impropyl acetate-toluene, acetone-water, etc.
The mixing ratio of these can be selected as appropriate depending on the solubility of the nonvolatile desensitizer and the solubility of the coloring ink, but from the viewpoint of erasing power and rewriting speed, the weight of the low boiling point solvent and the high boiling point solvent is The ratio is particularly preferably about 5:95 to 40:60.

The erasing material of the present invention can be easily obtained by mixing the above-mentioned components.

To erase handwriting made with colorless dye-developer ink using a vanishing material solution, apply the vanishing material solution onto the handwriting with a brush, or use a container for a writing instrument such as a felt-tip pen or felt-tip pen. Can be filled and used.

The present invention will be explained in more detail below with reference to Examples and Comparative Examples. Note that "parts" in Examples and Comparative Examples all indicate "parts by weight."

Example 1 (Preparation of colorless dye-developer-based ink) Novolac type phenolic resin [Tamanol PAJ (manufactured by Arayo Kagaku ■) (developer)
10 parts p-Ruzol-formalin initial shrinkage product (color developer) 20 parts fluorane colorless dye rBK-14J 9- (manufactured by Yamada Chemical Industry 1rJl) 15 parts crystal violet lactone (colorless dye) 2 parts benzyl alcohol 3o group ethylene Glycol monophenyl ni'chill 23 parts The above-mentioned mixture was heated and melted at 100°C for 1 hour, and then filtered to remove a small amount of insoluble matter to obtain a black colored ink. Apply this ink to ball hair (J I
A writing instrument erasable with the erasable material of the present invention was prepared by filling a SSS 6039-1980 E type for fine print) with the erasable material of the present invention.

(Preparation of erasing material) N-vinylpyrrolidone-vinyl acetate copolymer (3nia) (desensitizer) 10 parts Tetrahydrofuran (boiling point 66°C) 20 parts ethyl alcohol (boiling point 783°C) 70 parts of each of the above components The mixture was mixed and stirred at 50°C for 1 hour to obtain -10 = ink erasing material of the present invention. Fill the parts of an oil-based marker (M-10 manufactured by Pentel Co., Ltd.) with the stiffness to make an eraser 17.
P 3201. When I rubbed the handwriting on writing paper A) 2 to 6 times, I was able to completely erase it.

After 15 seconds of erasure, I wrote again on this erased trace using the black ink ballpoint pen mentioned above, and was able to clearly write on it.

Comparative Example 1 (Adjustment of erasing material) N-vinylpyrrolidone-vinyl acetate copolymer (3-nea)
(Desensitizer) 10 parts Tetrahydrofuran (boiling point 66°C) 90 parts The above items were added to Example 1. In the same manner as above, the ink erasing material was adjusted and marker type erasers 1 to 3 were produced. Example 1 using this eraser. When I rubbed the black ink ballpoint pen brush W1 made in , I was able to completely erase it.

After 15 seconds of erasing this erased trace, I redrew it with Toki's black ink ballpoint pen, and the handwriting was so faint that I could barely write on it.

It was after 60 seconds that I was able to write clearly again.

Comparative Example 2 (Adjustment of erasing material) N-vinylpyrrolidone-vinyl acetate copolymer (3-nea)
(Desensitizer) 10 parts Ethyl alcohol (boiling point 783°C) 90 parts
Example 1. The ink erasing material was prepared in the same manner as above, and a marker type eraser was produced. When I used this eraser to rub the black ink ballpoint pen marks made in Example 1,
Erasing was a little difficult, and some parts remained that could not be completely erased.

U Town L (Adjustment of eraser) Ethylene urea-butyraldehyde m1lh (desensitizer)
10 parts ethyl acetate (boiling point 77
．． 2℃) 25 parts toluene (boiling point 110.6℃)
) 65 parts The above components were mixed and stirred at 50° C. for 1 hour to obtain an ink erasing material of the present invention. Fill the parts of a permanent marker (Pentel (manufactured M-10) with this to make an eraser, and rub the handwriting made with the black ink ballpoint pen of Example 1 on the paper surface (JTS P 3201 writing paper A) 2 to 6 times. I was able to completely erase it.

After 20 seconds of erasing, I wrote again on this erased trace with the above black ink ballpoint pen, and was able to write clearly.

Comparative Example 3 (Preparation of erasing material) Ethylene urea-butyraldehyde resin (M sensitizer 9 10 parts Ethyl acetate (1 astigmatism 77.2°C) 90 parts - Ink erasing material prepared using the same ingredients as in Example 2) When the black ink ballpoint pen handwriting made in Example 1 was rubbed using this 16-eraser, it was able to be completely erased.

After 20 seconds of erasing the erased trace, I wrote again with Niki's black ink ballpoint pen, and the handwriting became so faint that I could barely write on it.

It was in 55 (after Fushi) that I was able to write clearly again.

Comparative Example 4 (Adjustment of erasing material) Ethylene urea-butyraldehyde resin (desensitizer) 10 parts toluene (
Boiling point: 1106° C.) 90 parts An ink eraser was prepared in the same manner as in Example 2 above, and a marker type eraser was prepared. When this eraser was used to rub the handwriting made with the black ink ballpoint pen in Example 1, the erasing power was weak and the handwriting could not be completely erased.

As shown above, the erasing material of the 1Jj1H color dye-developer 14-based ink of the present invention is excellent in its erasability, rewriting ability, and practicality.

Patent applicant: Pentel Co., Ltd. 15-

Claims (1)

[Claims] In the colorless dye-developer-based ink erasing material, which is prepared by dissolving in a solvent a nonvolatile desensitizer that decolorizes a color-forming ink containing a color developer and a colorless dye that is colored by the colorless dye, As a solvent for the erasing material, a low boiling point solvent that is a good solvent for the coloring ink and has a boiling point of 120°C or less, and a low boiling point solvent that is a poor solvent for the coloring ink and has a boiling point higher than the low boiling point solvent, and the low boiling point A colorless dye characterized by using a mixed solvent consisting of a high boiling point solvent that does not azeotrope with the solvent.
Eraser for developer-based ink.