JPS61204286A - Ink composition for mechanical recording - Google Patents

Abstract

PURPOSE:An ink composition that contains a specific dibasic acid ester, specific organic solvents and specific oil-soluble dyes, thus being suitable for mechanical recording such as printer, plotter, recorder or the like, because its vaporization is inhibited and shows high water resistance. CONSTITUTION:The objective composition contains (A) usually 5-90wt% of at least one of dibasic acid esters selected from dimethyl succinate, dimethyl glutarate and dimethyl adipate, (B) preferably 5-80wt% of at least one of organic solvents selected from carbitols, cellosolves and alcohols and (C) preferably 3-15wt% of oil-soluble or water-insoluble basic dyes.

Description

[Detailed description of the invention] Industrial applications The present invention relates to an ink composition for mechanical recording.

More specifically, the present invention relates to an ink composition that suppresses evaporation and has excellent water resistance and is suitably used for mechanical recording such as printers, plotters, and recorders.

2. Description of the Related Art Conventionally, water-based inks and high-viscosity oil-based ballpoint pen inks have been used as mechanical recording inks for printers, plotters, recorders, and the like.

However, water-based ink has drawbacks such as, for example, if you leave the writing instrument without a cap, the ink will evaporate, making it difficult to write the first time, blurring letters, or making it impossible to write. Furthermore, since it is not water resistant, there are problems in that when the written characters get wet with water, they become smudged or erased, making them difficult to read.

On the other hand, high viscosity oil-based ballpoint pen ink uses a zelkova solvent, so although the above-mentioned drawbacks of water-based ink can be improved to some extent, resin is usually added to prevent direct current, backflow, and smearing. It has a high viscosity, so if it is used in a writing instrument with a pen tip or a capillary type writing instrument made of fiber, felt, monofilament, etc., the flow of ink will be blocked, resulting in the inability to write or running out of ink. There are some drawbacks, and even when used with other writing instruments, there are drawbacks such as poor first-time writing, smudges, lack of clarity in drawn lines, and easy to blur, especially at low temperatures. have.

Also, there is marker ink that uses an organic solvent, but since this uses a solvent with a low boiling point although it has a low viscosity, the ink may evaporate if left with the cap removed. It is unsuitable as an ink for mechanical recording because it has problems such as smudging of written characters and ink penetrating into the back side of the paper.

Problems to be Solved by the Invention An object of the present invention is to solve these problems and provide an ink composition with excellent performance that can be suitably used for mechanical recording such as printers, plotters, and recorders. There is a particular thing.

Means for Solving the Problems As a result of extensive research, the present inventors have found that certain dibasic acid esters have low viscosity at room temperature, have low volatilization, have low vapor pressure, and are compatible with many organic solvents. However, the range of dyes that can be dissolved is relatively narrow, whereas organic solvents such as carbitols, cellosolves, and alcohols are compatible with the dibasic acid ester. Focusing on the fact that it has solubility and can dissolve many oil-soluble dyes and water-insoluble basic dyes, the above objective was achieved by combining the above-mentioned dibasic acid ester, organic solvent, and dye. They discovered scales and completed the present invention based on this knowledge.

That is, the present invention provides (A) at least one dibasic acid ester selected from dimethyl succinate, dimethyl glutarate, and dimethyl adipate; (B) carbitols, cellosolves, and alcohols; The present invention provides an ink composition for mechanical recording, comprising at least one organic solvent and (C) an oil-soluble dye or a water-insoluble basic dye.

The dibasic acid ester used as component (A) in the composition of the present invention is dimethyl succinate, dimethyl glutarate, or dimethyl adipate, each of which may be used alone or in combination of two or more. May be used. These dibasic acid esters can dissolve a part of the oil-soluble dye or water-insoluble basic dye used as component (C), and also have a low viscosity at room temperature, a small amount of volatilization, and a low vapor pressure. It has excellent properties such as a small amount of carbon dioxide and compatibility with many organic solvents.

Regarding the content of this dibasic acid ester, if it is too low, the effect of the present invention will not be effectively exhibited, and the upper limit is the amount of the dibasic acid ester of the oil-soluble dye or water-insoluble basic dye used. Although determined by solubility, it is usually selected in the range of 5 to 90% by weight based on the composition.

In the composition of the present invention, organic solvents used as the same component include diethylene glycol monomethyl ether (methyl carbitol), diethylene glycol monoethyl ether (ethyl carbitol), carbitols such as ethylene glycol monomethyl ether (methyl cellosol), ethylene glycol monoethyl ether, etc. (ethyl cellosolve), and alcohols such as ethanol, butanol, and benzyl alcohol. These organic solvents may be used alone or in combination of two or more.

The organic solvent has a high boiling point and has the property of easily dissolving oil-soluble dyes and water-insoluble basic dyes,
It is preferably used in a range of 5 to 80% by weight based on the composition. If this amount exceeds 80% by weight, the effects of the present invention will not be exhibited, and if this amount is less than 5% by weight, it will be difficult to dissolve the dye.

The dye used as component (C) in the composition of the present invention is an oil-soluble dye or a water-insoluble basic dye. GRH(C
, Esolpent Orange 37), Spiron Red BKH
(C, Esolvent Red 85), Sudan Blue Base (C, Esolpent Blue 35), etc. Examples of water-insoluble basic dyes include Rhodamine (C, Everthick Red 1), Methyl Violet (C, Eversick Violet 1), Malachite Green (C, Eversick Green y4L), Crystal Violet (C3, Eversick Violet 5), Victoria Blue BQI
Examples include free bases such as ((C, Eversick Blue-7)).

These dyes may be used alone or in combination of two or more, and the amount thereof is preferably in the range of 3 to 15% by weight based on the composition. If this amount is less than 3% by weight, clear drawn lines cannot be obtained, and if it exceeds 15% by weight, the viscosity of the composition is high and the followability of the ink is poor during high-speed writing, resulting in blurred lines.

Furthermore, for example, surfactants, antibacterial agents, rust preventives, lubricants, and the like can be added to the composition of the present invention, if necessary.

Effects of the Invention The ink composition for mechanical recording of the present invention can be used in capillary-type writing instruments, and as a result, the amount of ink transferred to paper is small and written characters do not bleed, and the ink does not bleed onto the back side of the paper. Clear, thin letters can be changed to prevent penetration. Furthermore, since the ink does not evaporate even if left without a cap for a long time, it has good initial writing properties, can be written without blurring, does not shorten the writing distance, and the dye used is non-water soluble. Therefore, even if the written characters get wet, they will not get dirty.
It has the advantage of not disappearing.

Example Next, the present invention will be explained in more detail with reference to Examples.

Example 1 Methyl Violet) (C, Eversick Violet 1) was dissolved in ethyl cellosolve, dimethyl adipate was added, stirred at room temperature for 2 hours, and filtered to obtain an ink composition having the following composition. Ta.

Ink composition Dimethyl adipate 65% by weight Ethyl cellosolve 30% by weight Methyl violet 5% by weight This ink composition was filled into a ballpoint pen writing instrument using batting, the cap was removed, the device was left at room temperature for one month, and then tested. It was possible to write smoothly at first without blurring, and the written characters hardly smeared even when wet.

Example 2 After dissolving Barry Fast Red #3304 (C, Esolvent Red 8) in ethyl carbitol, dimethyl glutarate was added, stirred at room temperature for 2 hours, and filtered to obtain an ink composition having the following composition. I got it.

Ink composition Dimethyl glutarate 75% by weight Ethyl carbitol 20% by weight Barry Fast Red #3
504 5% by weight This composition was tested in the same manner as in Example 1, and the same results as in Example 1 were obtained.

Example 3 After dissolving Oil Blue #605 in benzyl alcohol, dimethyl adipate was added, the mixture was stirred at room temperature for 2 hours, and then filtered to obtain an ink composition having the following composition.

Ink composition Dimethyl adipate 55% by weight Benzyl alcohol 40% by weight Oil Blue #603 5% by weight When this composition was tested in the same manner as in Example 1, the same results as in Example 1 were obtained.

Claims (1)

[Claims] 1 (A) At least one dibasic acid ester selected from dimethyl succinate, dimethyl glutarate, and dimethyl adipate, (B) At least one selected from carbitols, cellosolves, and alcohols. An ink composition for mechanical recording comprising: (C) an oil-soluble dye or a water-insoluble basic dye.