JPH11279475A - Oily ink for marking pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an oily ink having such mutually contradictory performances as dry-up resistance and short setting time. SOLUTION: This oily ink for marking pens essentially comprises a dye, an organic solvent, a resin soluble to the above organic solvent, and a saturated fatty acid ester which is made from a higher fatty acid selected from tetradecanoic acid, pentadecanoic acid and hexadecanoic acid and a higher aliphatic alcohol selected from tetradecanol, pentadecanol, hexadecanol, heptadecanol and octadecanol.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil-based ink used for a so-called quick-drying oil-based marking pen which allows a writing object to be written irrespective of absorbency or non-absorptivity.

[0002]

2. Description of the Related Art A quick-drying oil-based marking pen can be written not only on paper but also on glass, ceramics, cloth, etc., and after writing, the writing line dries quickly.
If the cap is left with the cap removed, the pen tip dries and the resin or the like hardens, and there is a drawback that writing becomes impossible. This is what is called dry-up. In order to solve this drawback, oil-based inks containing various dry-up inhibitors are disclosed in JP-A-51-120826, JP-B-52-44244, JP-A-57-28177, JP-A-61-34080 and JP-A-61-34080. -261380 and JP-A-62-135578. However, in order to effectively prevent dry-up, the dry-up inhibitor must be incorporated in a large amount, and then the drying time of the writing line, which is the most characteristic of oil-based ink (hereinafter, referred to as There is a new disadvantage that the "set time" is delayed.

[0003]

Accordingly, as a result of research, the present applicant has succeeded in finding an oil-based ink having contradictory properties such as dry-up resistance and short set time.

[0004]

An oil-based ink for a marking pen containing at least a dye, an organic solvent, a resin soluble in the organic solvent, and a saturated fatty acid ester, wherein the saturated fatty acid ester is tetradecanoic acid or pentadecanoic acid or This problem can be solved by an ink that is a saturated fatty acid ester of a higher fatty acid selected from hexadecanoic acid and a higher fatty alcohol selected from tetradecanol, pentadecanol, hexadecanol, heptadecanol, or octadecanol. In addition, the dye is a salt-forming type oil-soluble dye, and the organic solvent is methanol, ethanol, propanol, a lower aliphatic alcohol alone or a mixture of two or more selected from butanol, or the lower aliphatic alcohol. An ink which is a mixed solvent of an alcohol and a lactic acid ester, and wherein the resin is a ketone formaldehyde resin, an alkylphenol resin, or a rosin-modified resin, is more preferable. Further, an ink in which the saturated fatty acid ester is 0.01% by weight to 1.00% by weight, particularly 0.55% by weight to 0.95% by weight, based on the total amount of the ink is more preferred.

Hereinafter, the present invention will be described in detail. In the present invention, an oil-soluble dye is used as a coloring agent, and an oil-soluble dye such as monoazo, disazo, metal complex salt type monoazo, anthraquinone, phthalocyanine, and triallylmethane, which are generally commercially available as an oil-based marking pen dye, can be used. Among them, salt-forming type oil-soluble dyes show the most preferable results. Salt-forming type oil-soluble dyes are dyes in which hydrophilic groups such as acid dyes, direct dyes, and basic dyes are substituted with hydrophobic groups.In the present invention, the hydrophilic groups of the acid dyes are replaced with cationic activators, resin bases, amines.・ Substituted with a hydrophobic group such as a basic dye, etc., the hydrophilic group of the direct dye is replaced with a cationic activator ・ Resin base ・ Amine ・ Substituted with a hydrophobic group such as a basic dye, etc., and the hydrophilic group of a basic dye is an anionic activator・ Resin acid ・ acid dye ・
Those directly substituted with a hydrophobic group such as a dye can be used.

As the organic solvent, a lower aliphatic alcohol is essential, and is selected from methanol, ethanol, propanol and butanol. Propanol and butanol have respective isomers, but those having any structure such as normal, iso, and tertal can be used. The lower aliphatic alcohols may be used alone or as a mixture of two or more. Good results can be obtained by using a mixture of these lower aliphatic alcohols and lactic acid esters. As lactate, methyl lactate, ethyl lactate,
Choose from propyl lactate and butyl lactate. Although propyl lactate and butyl lactate have respective isomers, those having any structure such as normal, iso, and tertal can be used.

[0007] The resin is an oil-soluble resin, rosin resin,
Ester resins, cellulose resins, phenol resins, and the like can be used, but ketone formaldehyde resins and alkylphenol resins are particularly preferably used.

[0008] Saturated fatty acid esters include tetradecanoic acid,
A saturated fatty acid ester of a higher fatty acid selected from pentadecanoic acid and hexadecanoic acid and a higher fatty alcohol selected from tetradecanol, pentadecanol, hexadecanol, heptadecanol and octadecanol is used. The higher fatty acid and the higher aliphatic alcohol each have a large number of isomers. However, if the combination of the esterified saturated fatty acid esters does not have a melting point of 20 ° C. or lower, a straight chain or a branched chain may be used. Any one can be used. In the present invention, particularly, tetradecyl tetradecanoate, tetradecyl hexadecanoate, hexadecyl tetradecanoate, hexadecyl hexadecanoate, octadecyl tetradecanoate, and octadecyl hexadecanoate are preferably used. The saturated fatty acid esters can be used alone or in combination of two or more. The compounding amount exerts the effect of the present invention in the range of 0.01% by weight to 1.00% by weight based on the total amount of the ink, but the range of 0.55% by weight to 0.95% by weight shows particularly preferable results. .

In the present invention, additives usually used for inks such as preservatives, fungicides, dye dissolution aids such as amines, and penetrants such as benzyl alcohol can be added.

[0010]

The present invention will be described below with reference to examples. (Example 1) Salt-forming dye of tartrazine and rhodamine 6G 6.0% by weight Ethanol 66.0% by weight Ethyl lactate 16.0% by weight Alkylphenol resin 11.4% by weight Tetradecyl tetradecanoate 0.3% by weight Hexadecyl hexadecanoate 0 By mixing more than 0.3% by weight of a substance, a red ink was obtained. Comparative Example 1 A red ink was prepared from Example 1 except that tetradecyl tetradecanoate and hexadecyl hexadecanoate were removed. (Example 2) Salt forming dye of Victoria Pure Blue and acidic phthalocyanine blue 6.0% by weight Ethanol 61.0% by weight n-propanol 18.0% by weight Ketone formaldehyde resin 14.2% by weight Tetradecyl hexadecanoate 0.5% by weight % Octadecyl tetradecanoate 0.3% by weight or more was mixed to obtain a blue ink. (Comparative Example 2)
A blue ink was prepared by removing the tetradecyl hexadecanoate and octadecyl tetradecanoate from Example 2. (Example 3) Salt-forming dye of tartrazine and rhodamine 6G 6.0% by weight n-propanol 73.0% by weight n-butanol 10.3% by weight Ketone formaldehyde resin 10.0% by weight Tetradecyl tetradecanoate 0.2% by weight Hexadecyl tetradecanoate 0.4% by weight Hexadecyl hexadecanoate 0.1% by weight or more was mixed to obtain a red ink. Comparative Example 3 A red ink was prepared from Example 3 except that tetradecyl tetradecanoate, hexadecyl tetradecanoate, and octadecyl hexadecanoate were removed. (Example 4) Salt-forming dye of tartrazine and rhodamine 6G 6.0% by weight Ethanol 66.0% by weight Ethyl lactate 16.0% by weight Alkyl phenol resin 11.4% by weight Tetradecyl tetradecanoate 0.1% by weight Hexadecyl hexadecanoate 0 0.1% by weight or more of the substance was mixed to obtain a red ink. Comparative Example 4 A red ink was prepared by removing tetradecyl tetradecanoate and hexadecyl hexadecanoate from Example 4.

A test was conducted by filling the marking pens comprising a main body having a fiber pen core, an ink absorber and a cap with the inks of the above Examples and Comparative Examples. After leaving the cap of the marking pen for 8 hours in a room at a temperature of 20 ° C. and a humidity of 65%, the marking pen was left untouched for 8 hours, and then written on paper to examine the writability immediately after writing. ：: A clear writing line was obtained. X: Only a faint writing line was obtained. Writing was performed on an OHP film made of polypropylene using the marking pen, and the set time was examined. The test results are listed below.

[0012]

[Table 1]

[0013]

[Effect] Since a specific saturated fatty acid ester is blended, a weak film is formed at the pen tip even if the cap is left unattended, so that dry-up of the ink can be prevented. When writing again, the film is easily broken and writing is possible. Further, since the present invention is not affected by the setting time, a writing line which dries quickly can be obtained.

Claims (6)

[Claims] 1. An oil-based ink for a marking pen containing at least a dye, an organic solvent, a resin soluble in the organic solvent, and a saturated fatty acid ester, wherein the saturated fatty acid ester is selected from tetradecanoic acid, pentadecanoic acid, and hexadecanoic acid. Oil for a marking pen, which is a saturated fatty acid ester of a higher fatty acid and a higher fatty alcohol selected from tetradecanol, pentadecanol, hexadecanol, heptadecanol or octadecanol. 2. The oil-based ink for a marking pen according to claim 1, wherein the dye is a salt-forming type oil-soluble dye. 3. The method according to claim 1, wherein the organic solvent is selected from methanol, ethanol, propanol, and butanol.
The oil-based ink for a marking pen according to claim 1, which is a lower aliphatic alcohol obtained by mixing the above, or a mixed solvent of the lower aliphatic alcohol and a lactic acid ester. 4. The ink for a marker pens according to claim 1, wherein the resin is a ketone formaldehyde resin, an alkylphenol resin, or a rosin-modified resin. 5. The oil-based ink for a marking pen according to claim 1, wherein the content of the saturated fatty acid ester is 0.01% by weight to 1.00% by weight based on the total amount of the ink. 6. The oil-based ink for a marking pen according to claim 1, wherein the content of the saturated fatty acid ester is 0.55% by weight to 0.95% by weight based on the total amount of the ink.