JPS5949950B2 - Black water-based ink for optical mark reading devices - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an optical mark reading device (OMR, Optlc-a).
lMarkReader, OCR: OpticalCh
More particularly, the present invention relates to an ink for optical mark reading devices that is erasable and has no unpleasant odor.

Conventionally, character symbols, etc. (
(hereinafter referred to as information), use a mechanical pencil,
Pencils etc. have been mainly used.

However, when using such writing instruments, the density of the lead used is limited, reading errors occur due to uneven shading that occurs when writing information, and the mark sheet is subject to physical effects such as friction within the device, causing the mark sheet to There was a problem in that the outside of the information column became dirty or the information part became unclear, resulting in reading errors. Recently, in order to solve these problems, oil-based inks using nigrosine dyes have been developed. However, with this ink, since it is difficult to erase the dye, which is a coloring substance, it is impossible to erase incorrectly written personal information, and it is necessary to rewrite the information on a new mark sheet, which reduces work efficiency. , and an unpleasant odor, which caused problems such as the inability to work for long periods of time due to physiological problems. Therefore, in order to solve the conventional problems described above, the inventor of the present invention believed that it is basically better to use ink, and as a result of preliminary research, the reflectance at the light source wavelength used for 1 OMR and OCR was determined. is 70% or less and contains a substance that sufficiently absorbs near-infrared rays of 7,000λ or more.

2. The substance mentioned in 1 above should be soluble in water and/or an organic substance with a relatively slow evaporation rate and little unpleasant odor.

3. The substance mentioned in 1 above must be able to withstand repeated irradiation or long-term storage.

4. The substance mentioned in 1 above is erasable.

The present invention was completed based on the conclusion that the ink composition must satisfy the following conditions.

That is, the present invention uses iron catechol monosulfonic acid, iron catechol monosulfonate, iron catechol disulfonate, iron catechol disulfonate, monoferrous hydroxyquinoline sulfonate, and hydroxyquinoline sulfonate as coloring substances. - one or two complexes selected from iron;
The gist of this invention is a black water-based ink for optical mark reading devices that does not contain more than 8 to 65 weight axes. Hereinafter, the ink of the present invention will be explained in detail.

Various complexes are used as coloring substances, and catechol-3 is used as a catechol-sulfonic acid-iron complex
-monoiron sulfonate (bivalent) complex, catechol-3-monoiron sulfonate (trivalent) complex, catechol-4-monoiron sulfonate (bivalent) complex, iron 4-sulfonate (trivalent) Catechol 3-sulfonate monoiron (bivalent) complex as a complex, li kong tecol monosulfonate monoiron complex,
Catechol mono-3-sulfonate-iron (trivalent) complex, catechol-4-sulfonate monoiron (bivalent) complex, catechol-4-sulfonate monoiron (trivalent) complex, catesur disulfonic acid Examples of the monoiron complex include catechol-3.5-disulfonic acid (bivalent) complex, catechol-3.5-disulfonic acid (trivalent) complex, and catechol-3.5-disulfonic acid monoiron (trivalent) complex. - Disulfonate monoiron (bivalent) complex, catechol mono-3.5-disulfonate monoiron (trivalent) complex, and hydroxyquinoline-sulfonate monoiron (8-hydroxyquinoline-1-5-iron sulfonate complex). 8-hydroxyquinoline-5-sulfonic acid monoiron (trivalent) complex, etc. as hydroxyquinoline-5-sulfonate monoiron (bivalent) complex, 8-hydroxyquinoline-5
-sulfonate monoiron (trivalent) complexes, etc., and one or more of these are selected and used as an ink until a black color is obtained. So, should these complexes be used in an amount of 8 to 65% by weight based on the total amount of ink? is preferable, especially 15
~65 weight? is suitable. The amount of complex used is 80 weight?
In the following cases, the ink density will be low, reading errors will occur frequently, and 65 weight? In these cases, the viscosity of the ink increases, making it impossible to fill it into a writing instrument, or it does not penetrate the fibers that make up the mark sheet, making it difficult for the marked information to dry, resulting in weak shelf friction. Either of these is undesirable because it may stain the outside of the information column of the mark sheet and cause reading errors to occur. These complexes as colored substances can be easily erased with a solution containing a masking agent such as oxalic acid, citric acid, or ethylenediaminetetraacetic acid.

In addition to the complex as a coloring substance, water is used as a solvent, and if necessary, solubilizing agents such as ethylene glycol, urea, and methoxybutylene are used to improve the solubility of the complex and adjust the physical properties of the ink. and desiccants, preservatives, water-soluble resins, and nonionic surface active agents such as polyoxyenalene alkyl ether, polyoxyenalene alkylaryl ether, and polyoxyenalene alkyl ester, di-sulfuric fatty acid esters, and high-grade Penetrants such as negative ink surfactants such as alcohol sulfate ester salts are used.

Next, examples of the present invention will be described. In the examples, parts simply refer to parts by weight. Example 1 Catecholsulfonic acid (mixture) Iron (trivalent) complex...25.0 parts 8-hydroxyquinoline-5-sulfonic acid - Iron (trivalent) complex...
・10.0 parts water...
・・・・・・59.9 Enalene glycol
・・・・・・・・・ 5.0〃/Igen P (nonionic surfactant manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)・・・・・・・・・
A black liquid consisting of 0.1% was stirred for 2 hours using a stirrer to obtain a black ink.

Example 2 Monoiron (trivalent) catechol-3.5-disulfonate complex 20.0 parts 8-hydroxy/monoiron-5-sulfonate (trivalent) complex 15 ．．
0〃 Water ・・・・・・・・・
53.9 Enalene glycol ・・・・・・
... 5.0〃Unilube 50MB-5 (Nonionic surfactant manufactured by Nippon Yushiki Co., Ltd.)...6.0I/Neugen P
A black liquid of 0.1" was stirred with a stirrer for about 1 hour to obtain a black ink.

The inks obtained in Examples 1 and 2 were filled into a writing instrument similar to a commercially available felt-tip pen, and 10 mark sheets were filled with information (about 150 places per sheet) for a reading test (Fujitsu (Using optical mark reading device manufactured by Co., Ltd.)
The results are shown below.

For comparison, an ink with a low complex concentration (Comparative Example 1), an ink with a high complex concentration (Comparative Example 2), and a pencil...
A similar reading test was also conducted for hardness B (Comparative Example 3). Comparative example 1 Catechol-3,5-disulfonic acid iron (trivalent) complex 67.0 parts water
・・・・・・・・・27.9
〃ethylene glycol ·········
5.0 Neugen P ・・・・・・
... 0.1'' Comparative example 2 Catechol - 3.5-disulfonic acid = iron (trivalent) complex ...... - 5.0 parts water ・
・ ・ ・・・・・・ 89.9 parts enalene glycol ・・・・・・・・・ 5.0〃/IgenP ・ ・
・・ ・ ・ ・ ・ 0.1 Both Comparative Examples 1 and 2 were stirred with a stirrer for 2 hours to obtain black ink.

Comparative Example 3 Also, after filling in the mark sheet in Examples 1 and 2, dimercaptosuccinic acid (5.0 parts by weight) and oxalic acid (5.0 parts by weight) were added.
(parts by weight), Neugen P (1.0 parts by weight), water (81.0 parts by weight).
When the written portion was erased with an erasing liquid consisting of 0 parts by weight, it was easily erased.

Claims (1)

[Claims] 1 Coloring substance selected from catechol monosulfonic acid-iron, catechol monosulfonate-iron, catechol disulfonic acid-iron, catechol disulfonate-iron, hydroxyquinoline sulfonic acid-iron, hydroxyquinoline sulfonate-iron One or more complexes in 8
A black water-based ink for optical mark reading devices containing ~65% by weight.