JP3757619B2 - Water-based ink for ballpoint pens - Google Patents

Description

上記各成分を撹拌機を用いて撹拌混合し青色インキを得た。
【００１５】
実施例２

上記各成分を撹拌機を用いて撹拌混合し青色インキを得た。
【００１６】
実施例３

上記各成分を撹拌機を用いて撹拌混合し緑色インキを得た。
【００１７】
実施例４

上記各成分を撹拌機を用いて撹拌混合し青色インキを得た。
【００１８】
実施例５
Ｃ．Ｉ．ダイレクトブラック１９ ９．０重量部
Ｃ．Ｉ．アシッドレッド８ ０．５重量部
Ｃ．Ｉ．アシッドバイオレッド１５ ０．５重量部
Ｌ−アスコルビン酸ナトリウム １．５重量部
ＤＤＰ−４（前述） ３．０重量部
水 ７０．５重量部
グリセリン ５．０重量部
プロピレングリコ−ル １０．０重量部
上記各成分を撹拌機を用いて撹拌混合し黒色インキを得た。
【００１９】
比較例１
実施例１においてＬ−アスコルビン酸を除き、その量だけ水を加えた他は実施例１と同様になして青色インキを得た。
【００２０】
比較例２
実施例３においてＤＤＰ−２を除き、その量だけ水を加えた以外は実施例３と同様になして緑色インキを得た。
【００２１】
比較例３
実施例４においてＬ−アスコルビン酸とＤＤＰ−８を除き、その量だけ水を加えた以外は実施例４と同様になして青色インキを得た。
【００２２】
上記実施例１〜５及び比較例１〜３で得たボールペン用水性インキを市販のボールペン（ボールぺんてるＲ５０、ぺんてる（株）製）に２．５ｇ充填して、試験用のボールペンを作成した。
【００２３】
上記試験用のボールペンを用いて、長期保管したものの書き味の低下について試験を行った。書き味試験は、試験用のボールペンを作成し、室温で１日間保管したものと、４０℃の恒温槽に３ヶ月放置し取り出して室温で１日間放置したものとについて比較した。
結果を表１に示す。
【００２４】
【表１】

【００２５】
書き味試験
上記インキを充填したボールペンを用いて、筆記抵抗値を数値化できる試験機、ＰＥＮ ＷＲＩＴＩＮＧ ＴＥＳＴＥＲ（ＭＯＤＥＬ ＳＰ−２、有限会社精機工業製）を使用し、筆記速度４±０．２ｍ／分、筆記荷重９８１ｍＮ（１００ｇｆ）、筆記角度７０°の条件で筆記を行い、ペンが自転して１周回るまでの筆記抵抗値を測定（相対比較値）し、１回転までの値の平均値として算出した。
【００２６】
【発明の効果】
以上、詳細に説明したように、本発明のボールペン用水性インキは長期間保管後でも、ボールの回転が円滑であり優れた書き味を持続するものである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a ballpoint pen water-based ink using a dye. More specifically, the present invention relates to a water-based ink for ballpoint pens that can smoothly rotate the ball even after a long period of time and exhibits excellent writing quality.
[0002]
[Prior art]
Conventionally, water-based ink for ballpoint pens contains at least a dye, water, and a water-soluble organic solvent. The dye forms a handwriting as a colorant. Water is a main solvent that dissolves dyes and other substances. The water-soluble organic solvent functions as a solubilizing agent that dissolves the dye stably with time, and also serves to adjust the nib drying property.
In addition, water-based inks for ballpoint pens contain various surfactants such as silicone oil and fluorine-based surfactants to prevent wear on the ball seat and improve writing distance, and to smooth the writing. It is known to add various types of lubricants. Further, in order to prevent corrosion of metal members such as balls and generation of mold against ink, it is generally performed to add a rust preventive or preservative.
[0003]
[Problems to be solved by the invention]
However, recently, in consideration of the influence on the human body and the environment, highly safe inks that do not use chemical substances that are highly toxic or dangerous have been demanded. This tendency is particularly strong in oil-based inks, but thiodiglycol, which is often used in water-based inks as a dye-dissolving aid in water-based inks, is part of the law concerning the prohibition of chemical weapons and the regulation of specific substances. It is designated as a chemical weapon precursor, and the user must notify the Minister of Trade and Industry of the planned quantity of use and past results, and avoid using it as much as possible.
However, when the composition of the ink is closer to water, it becomes unstable over time and affects writing characteristics as well as various writing characteristics. Further, when the amount of the water-soluble organic solvent is reduced or the type is limited, the writing quality is deteriorated due to the precipitation of the dye over time or the decrease in the lubricity of the ball surface.
The present invention provides a water-based ink for a ballpoint pen that uses a dye and does not deteriorate the writing quality after long-term storage without using thiodiglycol, and maintains a stable quality. Is an issue.
[0004]
[Means for Solving the Problems]
The gist of the present invention is a water-based ink for ballpoint pens containing at least a dye, L-ascorbic acid, dipolyoxyethylene alkyl ether phosphoric acid, and water.
[0005]
This will be described in detail below.
As the dye, any of direct dyes, acid dyes, basic dyes and the like can be used. However, depending on the type of the ball or chip material, corrosion may occur at low pH, so the pH is neutral to alkaline. It is preferable to use a direct dye or an acid dye that dissolves stably. An example is given below.
[0006]
Examples of direct dyes include C.I. I. Direct Black 17, 19, 19, 22, 32, 38, 51, 71, C.I. I. Direct yellow 4, 26, 44, 50, C.I. I. Direct Red 1, 4, 23, 31, 37, 39, 75, 80, 81, 83, 225, 226, 227, C.I. I. Direct Blue 1, 15, 71, 86, 106, 199 and the like.
[0007]
Examples of acid dyes include C.I. I. Acid Black 1, 2, 24, 26, 31, 31, 52, 107, 109, 110, 119, 154, C.I. I. Acid Yellow 7: 1, 17, 19, 23, 25, 29, 38, 42, 49, 72, 61, 78, 110, 141, 135, 127 142, C.I. I. Acid Red 8, 9, 9, 14, 26, 27, 35, 37, 51, 52, 57, 82, 87, 92, 94, 111, the same 129, 131, 138, 186, 249, 254, 265, 276, C.I. I. Acid Violet 15, 17 and C.I. I. Acid Blue 1, 7, 9, 15, 22, 23, 25, 40, 41, 43, 62, 78, 83, 90, 93, 103, 112, 113, 158, C.I. I. Acid Green 3, 9, 16, 25, 27 and the like.
[0008]
Examples of basic dyes include C.I. I. Basic Blue 7, C.I. I. Basic Red 1 etc. are mentioned.
[0009]
L-ascorbic acid and dipolyoxyethylene alkyl ether phosphoric acid in the present invention are used for improving the temporal stability in a ballpoint pen-based water-based ink using a dye and maintaining good writing quality. Note that L-ascorbic acid and dipolyoxyethylene alkyl ether phosphoric acid may be used as a free acid or an alkali metal salt such as a sodium salt.
The amount of L-ascorbic acid to be used is preferably 0.2 to 5.0% by weight, more preferably 0.5 to 3.0% by weight, based on the total amount of the ball-point pen aqueous ink.
[0010]
Specific examples of dipolyoxyethylene alkyl ether phosphoric acid include DDP-2 (dipolyoxyethylene (2) alkyl ether phosphoric acid), DDP-4 (four POE addition moles), and DDP-6 (same POE addition). Mole number 6), DDP-8 (the same POE addition mole number 8) (the above, Nikko Chemicals Co., Ltd. product) etc. are mentioned.
The polyoxyethylene addition mole number of dipolyoxyethylene alkyl ether phosphoric acid is preferably 2-8.
The amount of dipolyoxyethylene alkyl ether phosphoric acid used is preferably 0.5 to 5.0% by weight based on the total amount of the ball-point pen aqueous ink.
[0011]
Water is used as the main solvent. The amount used is preferably 30 to 95% by weight based on the total amount of the ballpoint pen water-based ink.
[0012]
In addition to the above components, a high-boiling water-soluble organic solvent such as glycol solvents such as ethylene glycol, diethylene glycol, and propylene glycol, and glycerin can be used in order to keep the nib drying property well. In view of safety, it is preferable to avoid the use of thiodiglycol or to reduce the amount of the solvent used. Furthermore, conventionally known additives such as low-boiling water-soluble organic solvents such as alcohol, polymer substances, surfactants, rust preventives, and lubricants may be appropriately selected and used depending on the application.
[0013]
[Action]
L-ascorbic acid is known as a highly active antioxidant, and it can be easily imagined that it acts to prevent dye oxidation even in ink. Further, dipolyoxyethylene alkyl ether phosphoric acid is also known to act as a rust preventive and is a known additive for ballpoint pen ink. However, even if each of the inks that do not use thiodiglycol, which is the object of the present invention, is used alone, it is not possible to obtain a stable ink like an ink that uses thiodiglycol. The intended effect can be obtained only when the two substances of the present invention are used in combination, and the action is presumed as follows.
Dipolyoxyethylene alkyl ether phosphoric acid contributes not only to the antirust effect but also to the dissolution stability of the dye over time. L-ascorbic acid has an antioxidant effect on the dye, but because of its immediate effect, it is difficult to maintain its effect in the long term. Therefore, dipolyoxyethylene alkyl ether phosphoric acid prevents ascorbic acid from immediately becoming oxidized ascorbic acid and maintains the original antioxidant action of ascorbic acid. Even after storage for a long period of time, the dye has excellent dissolution stability, can prevent oxidation on the metal surface, and does not deteriorate the writing quality.
[0014]
【Example】
Example 1

The above components were stirred and mixed using a stirrer to obtain a blue ink.
[0015]
Example 2

The above components were stirred and mixed using a stirrer to obtain a blue ink.
[0016]
Example 3

The above components were stirred and mixed using a stirrer to obtain a green ink.
[0017]
Example 4

The above components were stirred and mixed using a stirrer to obtain a blue ink.
[0018]
Example 5
C. I. Direct Black 19 9.0 parts by weight C.I. I. Acid Red 8 0.5 parts by weight C.I. I. Acid Bio Red 15 0.5 part by weight L-sodium ascorbate 1.5 part by weight DDP-4 (previously described) 3.0 part by weight water 70.5 part by weight glycerin 5.0 part by weight propylene glycol 10.0 part by weight Part The above components were stirred and mixed using a stirrer to obtain a black ink.
[0019]
Comparative Example 1
A blue ink was obtained in the same manner as in Example 1 except that L-ascorbic acid was removed in Example 1 and water was added in that amount.
[0020]
Comparative Example 2
Except for DDP-2 in Example 3, green ink was obtained in the same manner as in Example 3 except that water was added in that amount.
[0021]
Comparative Example 3
A blue ink was obtained in the same manner as in Example 4 except that L-ascorbic acid and DDP-8 were excluded and water was added in that amount.
[0022]
2.5 g of the water-based ink for ballpoint pens obtained in Examples 1 to 5 and Comparative Examples 1 to 3 was filled in a commercially available ballpoint pen (Ball Pentel R50, manufactured by Pentel Co., Ltd.) to prepare a test ballpoint pen.
[0023]
Using the above-described ballpoint pen for testing, a test was conducted on the deterioration of writing quality of what was stored for a long time. In the writing test, a ballpoint pen for test was prepared and stored at room temperature for 1 day, and a test was compared with a sample which was left in a constant temperature bath at 40 ° C. for 3 months and left at room temperature for 1 day.
The results are shown in Table 1.
[0024]
[Table 1]

[0025]
Writing test Using a ball pen filled with the above ink, a writing machine that can quantify the writing resistance value, PEN WRITEING TESTER (MODEL SP-2, manufactured by Seiki Kogyo Co., Ltd.), writing speed 4 ± 0.2 m / Minutes, writing load 981mN (100gf), writing under the conditions of a writing angle of 70 °, measuring the writing resistance value until the pen rotates and rotates once (relative comparison value), the average value of up to one rotation Calculated as
[0026]
【The invention's effect】
As described above in detail, the water-based ink for ballpoint pens of the present invention can smoothly rotate the ball and maintain excellent writing quality even after long-term storage.

Claims (2)

A water-based ink for ballpoint pens comprising at least a dye, L-ascorbic acid, dipolyoxyethylene alkyl ether phosphoric acid, and water. The water-based ink for ballpoint pens according to claim 1, wherein the polyoxyethylene addition mole number of dipolyoxyethylene alkyl ether phosphoric acid is 2-8.