JPS60141770A - Water-based printing ink - Google Patents

Abstract

PURPOSE:A water-based printing ink that contains a color-developing agent which is colorless on printing or becomes colorless naturally even if has a color at the beginning and develops the color by allowing the color-developing agent to act thereon, thus being used in documents, teaching materials having hidden printed parts or shipping packages with hidden numbers. CONSTITUTION:The objective water-based printing ink contains a color-developing agent that is colorless on printing or becomes colorless naturally, even it has a color at the start and develops the color by allowing a color-developing auxiliary to act on the agent, preferably p-nitrophenyl, gamma-dinitro phenol, m-nitrophenol, cyanine, alpha-naphthol phthalein, ethyl-bis-acetic acid, phenolphthalein, o- cresolphthalein, hexamethoxyred, heptamethoxyred.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a color m that naturally disappears even if it is colorless or colored at the time of printing, and then changes color by applying a coloring aid.
+=0 regarding the water-based printing ink contained The applicant has made many proposals regarding printed matter containing all the coloring agents that change color due to the full action of the coloring auxiliary agent.
Application of printed matter that has symbols, figures, hieroglyphs, etc. on part or all of the paper surface, which can be colored by the full action of a coloring aid at any time and disappear naturally, in contrast to conventional printed matter that is simply made of visible ink. It has a wide range of uses, and it is thought that it will become indispensable, especially in fields such as teaching materials.

The ink of the present invention is an ink that can print the above-mentioned printed matter by letterpress printing, gravure printing, flexo printing, etc.

The coloring agent used in the present invention is a pi (indicator, etc.) that changes its coloration depending on pH, and in particular, T-dinitrophenol, p-nitrophenol, m-ditrophenol,
Cyanine, α-naphtholphthalein, ethylbisacetic acid, phenolphthalein, cresolbutanein, thymolphthalein.

Bromphenol burger, hexamethine red, hexamethoxy red, etc. have a decolorizing pf (preferably in the 9n range, but depending on the intended use, those with a decolorizing pH range are preferable). No p
Examples of solvents for dissolving the coloring agent, which may include an H indicator or a color-changing dye, include hydroalcohols, surfactants, and amines.

Alcohols Water-based alcohols such as tehamethyl alcohol and ethyl alcohol/inglobil alcohol are preferred, but some alcohols having almost no water solubility may also be added. Surfactants are broadly classified into anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants.1.Ionic surfactants include alkyl sodium sulfate, secondary alkyl sodium sulfate, - Sodium olefin sulfonate.

Representative examples include sodium N-acylamino acid, alkylnaphthalene sulfone, sodium acid, sodium N-ethyl-N-methylalkanamide, and dialkyl cosulfosuccinate.

Examples of cationic surfactants include N-ethylalkanamide ammonium halide, alkylpyridinium sulfate, and alkyltrimethylammonium halide; examples of cationic surfactants include alkylpolyoxine ethylene ether and alkylcarponyloxypolyoxy. Representative examples include ethylene, p-alkylphenyl polyoxyethylene ether, fatty acid polyhydric alcohol ether, fatty acid polyhydric alcohol polyoxyethylene, fatty acid sucrose ester, and amphoteric surfactants such as alkyl betaine and alkyl diethylene triaminoacetic acid. , any one may be used. Amines include methylamine, ethylamine, and isopropylamine.

Butylamine, ethanolamines, isopropanolamine i, l'J, N dimethylethanolamine, N,
There are a wide variety of N-diethylethanolamine, aminoethylethanolamine, 3-tatoxyglobylamine, 3-ethoxyglobylamine, 2-ethylhexylamine, etc., but depending on safety, water solubility, evaporation rate p)-1, etc. It is also possible to use a combination of a plurality of selected materials having different evaporation rates.

In addition to the above-mentioned solvents, water-soluble thickeners such as selagin, rosin, glue, gelatins, casein, and phenolic stool fat can be used as the ink vehicle.

Furthermore, to the above water-soluble main ingredients, drying vegetable oils such as tung oil and linseed oil, and synthetic resins such as rosin-modified phenolic resins are added, depending on the printing method, for the purpose of drying properties, adhesion to paper, prevention of bleeding, and tack adjustment. be able to.

The ink of the present invention has the above configuration and is applied to letterpress printing, flexographic printing, and gravure printing.

If the present invention is applied to ink for letterpress printing, it can be used in all markets, such as various problem sets with hidden printing sections, central documents, and other teaching materials that are very suitable for M. Moreover, if applied to gravure printing, it can be expected to have a very wide range of applications, such as interesting multi-color hidden prints, and if applied to full flexographic printing, for shipping management such as hidden numbering of shipping packages.

Example 1゜ The following ink was prepared as a letterpress ink.

O-cresol phthalein 15 parts Higher alcohol surfactant 40 parts Fatty acid surfactant 30 parts Triethanolamine 10 parts Glue 05 parts Rust preventive 5 parts All of the above inks were used, and Eagle 46 size manufactured by Kobundo was used. A 4-size automatic letterpress printing machine uses 4-size, 4-size high-quality paper (thickness 70 kg).
) was operated continuously for 8 hours at a printing speed of aooo sheets per hour.

The plate used was a resin board. Printed materials are English teaching materials, but
There is almost no variation in the coloring properties due to the coloring aid, and the yield is 997.
%Met. This ink could also be used for flexo printing.

Example 2゜ The following ink was prepared as a gravure ink.

Ink A Phenolphthalein 15 parts Higher alcohol surfactant 40 parts Fatty acid surfactant 30 parts Triethanolamine 10 parts Rust preventive 5 parts Ink B Ethylbisacetic acid 18 parts 0-olefin surfactant Paris 37 parts Fatty acid interface Active agent 30 parts Jetanolamine 10 parts Rust preventive 5 parts Ink C m-Nitrophenol 12 parts Higher alcohol surfactant 40 parts Fatty acid surfactant 33 parts Triethanolamine 5 parts Rust preventive 5 parts Acetic acid 5 3 using the above ink on a gravure printing machine manufactured by Mitsuwashi Co., Ltd.
Color printing was performed.

When a coloration aid was applied to a printed matter made with this ink, each color of the three-color combination stood out clearly.

Moreover, as the coloration aid expires, these pictures, letters, symbols, etc. will naturally disappear, making it possible to offer interesting printed matter to the market.

Patent applicant Kiyoharu Kawashima

Claims (2)

[Claims] (1) An aqueous printing ink containing a coloring agent that naturally fades even if it is colorless or colored at the time of printing, and later changes color by the action of a coloring aid. (2) Coloring agent Up-nitrophenol, T-dinitrophenol, m-nitrophenol, cyanine. α-naphtholphthalein, ethylbisacetic acid, phenolphthalein, 0-cresolphthalein. Thymolphthalein, bromophenol purple. The water-based printing ink according to claim 1, which is hexamethoxy red, heptamethoxy red, or a mixture thereof.