JPS5913552B2 - Water-based ink for ballpoint pens - Google Patents

Description

[Detailed Description of the Invention] The present invention adds a polyether-modified silicone resin to the ink, and its lubricity reduces the friction between the tip and ball of a ballpoint pen to prevent tip wear. At the same time, the present invention relates to a water-based ink for ballpoint pens that allows the ball to rotate smoothly and provides a smooth writing experience.

In the case of conventional water-based ballpoint pen inks, glycol solvents, glycol ether solvents,
A water-soluble dye such as a direct dye, an acid dye, or a basic dye is dissolved in an aqueous solution of a water-soluble organic solvent such as a glycol ether ester solvent or an amine solvent, and if necessary, preservatives, anions or non-containing agents are added. It is a low viscosity 5 (2 to 10 cps) ink made by adding an ionic surfactant,
In the case of this water-based ink, the disadvantages of oil-based ballpoint pen ink are that it has a hard writing feel and requires writing with considerable pressure to obtain clear writing lines, and it also suffers from the appearance of bores at the beginning and end of writing. Although this problem has been solved by the low viscosity of water-based ink, the ink itself has no lubricity, has a large coefficient of friction, and the friction between the ball and the tip during writing causes the ink to be made of generally used synthetic resin or If you use a metal tip that is not super hard like a machiyu, the tip will wear out, causing the ball to rattle, or causing a frictional sound between the ball and the tip when writing zero, which may result in poor writing quality. The drawback was that it was not smooth.

The present invention has been made as a result of various efforts to eliminate the drawbacks of water-based inks for ballpoint pens, and it has been discovered that a water-based ink containing polyether 5-modified silicone resin has an excellent tip abrasion prevention effect. It had come to completion.

A feature of the present invention is that the excellent lubricity of polyether-modified silicone resin reduces the friction between the ball and tip '0, thereby preventing wear of the tip and preventing the ball from slipping when writing. This has the effect of making the rotation smoother and giving a softer writing feel.

Furthermore, since the polyether-modified silicone resin is colorless and transparent when dissolved in water, it can be added not only to black ink but also to any other color ink composition such as red, blue, yellow, purple, etc. Lasts forever. When thinking about why polyether-modified silicone resin has such excellent lubricity, it reduces the friction between the ball and the tip and has the effect of preventing tip wear. The polyether-modified silicone resin used is considered to have excellent lubricity because it has a small boundary friction coefficient between metal-to-metal, metal-to-plastic, etc. Next, the polyether-modified silicone resin used in the present invention will be described.

Silicone resins include silicone oil, silicone rubber,
There are various kinds of silicone varnishes, etc., but the polyether-1-coutel-modified silicone resin used in the present invention is a copolymer of organopolysiloxane and polyether. For example, dimethylpolysiloxane is used as the organopolysiloxane, and polyethylene oxide is used as the polyether. When used, the following reaction occurs.

And it is optionally soluble in water.

When used as a ballpoint pen aqueous ink additive of the present invention, the amount used is preferably 0 to the total ink composition.
．． If it is less than 0.05% by weight, the lubricity of the ink will not be sufficient, and if it is more than 10% by weight, the surface tension of the ink will be affected by the low surface tension property of the polyether-modified silicone resin itself. There is a large drop in tension, below the appropriate surface tension, which causes handwriting to smear. Furthermore, since the viscosity of the ink exceeds the appropriate viscosity, the flow of ink in the ballpoint pen during writing becomes poor, causing a shift in the force of the handwriting. Preferably, 0.1 to 5% by weight is optimum.
The solvent and dye used in the water-soluble ink according to the present invention will be described. Any solvent may be used as long as it is compatible with water. Examples include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,5-pentanediol, thiodiethylene glycol, glycerin, ethylene glycol monobutyl ether, diethylene glycol mono One or more of the following are used: ethyl ether, diethylene glycol diethyl ether, ethylene glycol diethyl ether acetate, diethylene glycol monoethyl ether acetate, formamide, N,-merdimethylformamide, sorbitan, acetin, and the like. Preferable results can be obtained when the water-soluble organic solvent is used in an amount of 5 to 60% by weight based on the total amount of the ink composition, and 10 to 50% by weight for writing instrument inks. Most of the known water-soluble direct dyes, acidic dyes, and basic dyes can be used as dyes. Typical examples include Kayalus Black GcOnc (CI35255), Direct deep black EX (CI3O235), direct fast black COnc (CI2772O),
Direct First Black B (CI35435),
Direct Blue 2B (CI226lO), Direct Sky Blue 5B (CI244OO), Direct First Yellow GC (CI29OOOO) are available, and acid dyes include Mitsui Nylon Black GL (Cl57l).
l) Nigrosine NBcOnc (Cl5O42O), Water Black ◆21 (Cll5985, 42O9O,
42745 mixed dye), Eosin FA (CI4538
O), erythrosine (CI4543O), Phloxine P
B (CI4541O), Brilliant Scarlet 3R
c0nc (CIl6255), brilliant blue FC
F (CI42O9O), Solpur Blue 0BC (C42
755), naphthalene green S (Cl44O25), tartrazine (CIl9l4O), and basic dyes such as auramine 0cc (CI4lOOOO), astrazone yellow 3G (CI48O55), astrazone orange G (Cl48O35), rhodamine 6GCP (
CI45l6O), methyl violet FN (CI42
535) Crystal Violet Ex, pdr (CI4
2555), Rhodamine B (CI45l7O), Eisen Victoria Privilege BOH (CI42595), Methylene Blue COnc (CI52Ol5), Victoria Blue FB (CI44O45), Malachite Green (
CI42OOO), etc.

Therefore, these dyes are used in an amount of 0 based on the total amount of the ink composition.
．． 1 to 40% by weight, 0.5 to 3 for writing instrument ink
Favorable results are obtained when 0% by weight is used. Further, if necessary, a penetrating agent such as an anionic or nonionic surfactant, or a preservative such as sodium pentachlorophenol, phenol, formalin, etc. can be appropriately selected and used.

A ballpoint pen using the water-based ink obtained in this way has an excellent lubrication effect between the tip and a metal ball or a mineral ball such as a ruby, and has the effect of preventing wear of the tip.
For example, even if the chip is made of polyacetal resin other than metal, it has excellent wear resistance.

The present invention will be explained in more detail below with reference to Examples.

[Example 1] First, all amounts of ethylene glycol, diethylene glycol, and water were mixed and stirred, then the dye and the remaining components were sequentially added with stirring, and the mixture was stirred at room temperature for about 2 hours to obtain a black ink.

When this black ink was filled into a ballpoint pen with a polyacetal resin tip and a ruby ball and was used for writing, it showed excellent writing and dispersion, but when using an ink that did not contain polyether-modified silicone resin, the tip was severely worn and could be written at 600 m. However, the ink containing polyether-modified silicone resin X-22351 had a writing ability of 1300 m. [Example 2] First, the entire amount of thiodiethylene glycol and water were mixed and stirred, and then the remaining components of two or less dyes were sequentially added with stirring, and the mixture was stirred at room temperature for about 2 hours to obtain a red ink.

Claims (1)

[Claims] 1. A water-based ink for ballpoint pens, which is characterized in that the main components are a colorant, water, and/or a water-soluble organic solvent, and further contains a polyether-modified silicone resin.