JPS6028472A - Aqueous ink for ball point pen - Google Patents

Abstract

PURPOSE:To obtain titled ink with high lubricity and stability, and smooth writing touch, capable of preventing wear between chip ball holder and ball, by incorporating an ink composition with a specific amount of surface protective film-forming additive. CONSTITUTION:The objective ink can be obtained by incorporating (A) an ink composition with (B) 0.02-5wt% of a surface protective film-forming additive and further, (C) anionic or nonionic surfactant, water-soluble dye, etc. Said ink composition can be prepared by incorporating (1) water with (2) for example, 5-40wt% of a water-soluble polyhydric alcohol such as propylene glycol, (3) preservative, and, if required, (4) water-soluble resin.

Description

DETAILED DESCRIPTION OF THE INVENTION An object of the present invention is to provide a water-based ink for a ballpoint pen that has excellent lubricity, has a dynamic action that prevents wear between the ball holder of the dip and the ball, and has a smooth writing feel.

Conventional water-based inks for ballpoint pens contain water-soluble polyhydric alcohols such as glycol solvents and glycol ether ester solvents in an aqueous solution of water-soluble dyes. Part of the ball holder tends to wear out due to the rotation of the ball, which increases the gap between the ball and the ball holder, causing phenomena such as rattling of the ball and irregular rotation of the ball, resulting in poor initial performance. There were disadvantages such as the taste could not be maintained for a long time and the ink came out unevenly.

The present invention aims to overcome these drawbacks by blending an extreme pressure additive into an aqueous solution of a water-soluble dye to obtain a water-based ink with excellent lubricity, long-term stability, and bleeding prevention.

The water-based ink of the present invention has water as its main component, and glycol-based solvents such as etelene gelicol and pudelene glycol, celeryl-based solvents such as ethyl celeryl, methyl celeryl, and glycol ether esters such as edelene glycol monoethyl ether acetate. Contains 5 to 40% by weight of one or more water-soluble polyhydric alcohols such as solvents, and water-soluble dyes such as acid dyes, direct dyes, and basic dyes, preservatives, and nonionic or anionic surfactants. Furthermore, if necessary, extreme pressure additives are added to the ink solution containing water-soluble resin, which dramatically improves the lubricity that could not be obtained with conventional water-based inks. In the case of metallic materials such as phosphor bronze and stainless steel, the wear of the ball seat of the depth that comes into contact with the ball during writing is reduced, and the excellent writing feel and smooth writing quality that would otherwise lead to the consumption of ink is maintained. I can do it.

The amount of extreme pressure additive added is 0.00000000 for the total ink composition.
The optimal range is 0.02 to 5.0 weight percent.
If the amount is less than 0.02 weight percent, the ink composition will not have the desired lubricity, and if it exceeds 5 weight percent, bleeding will be observed when writing, and the ink will become unstable over time.

The ink of the present invention is characterized by the combined use of an extreme pressure additive and a surfactant, which allows the extreme pressure additive to easily adsorb to the metal surface of the ball and the ball seat.
A film (extreme pressure film) is created to create a strong thin film of ink within the small gap between the ball and the ball seat, reducing wear between the ball and the holder, maintaining a good writing feel, and improving writing performance. It is presumed that there are.

The present invention will be explained in detail below.

Example 1 Budelene glycol 10.0 Scoreolna 900 (surfactant) O,OS Phenol 0.1 Benzotriazole 0.1 Victoria Blue BB (dye) Z5 The above mixture was stirred at 40-60°C for 1 hour. After cooling and filtering, an ink was obtained. From this formulation Adeca Phosphate) AP
The results of comparing the sinking of the ball and the writing feel after writing with the ink of the comparative example in which No. 8-31 was removed and the ink of the above-mentioned example of the present invention using a mechanical writing tester for 500 rn are as follows.

Furthermore, the ink of the present invention does not bleed, has excellent dye solubility, and has excellent long-term stability.

Ethylene glycol 10.0 Glycerin 5.0 Florado yo-43o (surfactant) o, os
Phenol 0.1 Eosin 8.0 The above formulation was prepared in Example 1. The results of a similar comparison between the ink of this invention example and the ink of a comparative example in which the extreme pressure additive Adekaroop 0F-30 was removed are as follows.

Furthermore, the ink of the present invention does not bleed, has excellent dye solubility, and has excellent long-term stability.

Example 3゜Propylene glycol 20.0 Unidyne DS-1o:z (surfactant) O, OS
Phenol 0.1 Nigrosine R-50010.0 The above formulation was treated in the same manner as in Example 1, and the ink of this invention example and the extreme pressure additive Azokaposuny) APM-
The results of a similar comparison with the ink of the comparative example in which No. 45 was removed are as follows.

Furthermore, the ink of the present invention does not bleed, has excellent dye solubility, and has excellent long-term stability.

The water-based ink for ballpoint pens of the present invention has excellent lubricity as described above, which prevents wear between the ball and the ball holder, provides a smooth writing feel, and has excellent dye solubility and long-term stability.

46

Claims (1)

[Claims] A water-based ink for a ballpoint pen, characterized in that the ink composition contains 0.02 to 5.0 weight percent of an extreme pressure additive such as a water-soluble dye and a surfactant.