JPH0615277B2 - Ink backflow prevention composition for water-based ballpoint pen - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field The present invention has a viscosity of 50 to 2000 CPS (at 25 ° C.).
Regarding the improvement of the ink backflow preventive composition provided in the ink upper part of the ink pen in the ball-point pen using the water-based ink of the above, in particular, it is possible to prevent the ink from adhering to the inner surface of the ink container as much as possible and to make it impossible to write at low temperature. The present invention relates to an ink backflow preventive composition for water-based ballpoint pens that eliminates the problems as much as possible.

(Conventional technology and its problems) Since the oil-based ink that has been conventionally used for ball-point pens and the like using oil-based ink has a very high viscosity of several thousand to 10,000 CPS, it is accommodated. It is not necessary to equip the ink backflow preventive composition when the inner diameter of the ink containing tube is 2.8 (mm) or less, but when the inner diameter is 2.8 (mm) or more, the This is because there is a concern that ink may leak from the rear end of the ink containing tube when it moves forward in the direction of the pen tip as it is consumed, and when the writing instrument is impacted or placed in a high temperature environment. An ink backflow preventive composition composed of petroleum jelly, silicone grease, silicone oil, or a mixture of liquid paraffin and petroleum jelly must be provided on the upper portion of the ink in the ink containing tube. It is known that there is.

Due to the high viscosity of the ink, the oil-based ballpoint pen provided with such an ink backflow preventive composition is introduced into the pen tip without excess or deficiency by using the atmospheric pressure or its own weight during writing. The ink backflow preventive composition also follows the ink without sticking to the inner surface of the ink containing tube as the ink is consumed, and can prevent ink leakage from the rear end of the ink containing tube. However, such an ink backflow preventive composition has a viscosity of 50 to 50, which is lower in viscosity than oil-based inks.
If it is used as it is for a ball-point pen using a water-based ink of about 2000 CPS, the following problems will occur.

That is, the amount of ink released at the pen tip of a ballpoint pen using a low-viscosity water-based ink is about 0.2 compared to the value of about 0.03 (g / 200 m) for general oiliness.
(G / 200 m), which is very large, and therefore the speed at which the ink backflow preventive composition in the water-based ballpoint pen follows the ink is naturally high. Thus, the ink backflow preventive composition is required to respond to ink consumption promptly and surely, but in actuality, the ink backflow preventive composition does not affect the ink consumption rate. It becomes impossible to follow, and as a result, it is more likely to adhere to the inner surface of the ink containing tube as compared with the oil-based one, causing not only ink failure due to the reduced pressure in the ink containing tube, but also the ink backflow preventive composition. However, there is a problem in that the original purpose cannot be achieved, and in addition, such an ink backflow preventive composition has a problem in that the environment at low temperatures is low. As a result, the mesh structure becomes stronger and the flow characteristics are impaired, and as a result, the ability to follow the consumption of ink also deteriorates and eventually there is a problem that writing becomes impossible.

(Means for Solving Problems) In view of the above-mentioned circumstances, the present inventors have a viscosity of 50 to 200.
Various studies were conducted on various additives in order to solve the problem of the adhesion of the ink backflow preventive composition to the inner surface of the ink containing tube and the problem of the inability to write at a low temperature in a ballpoint pen using 0 CPS aqueous ink. As a result, a gelling agent, a glycerin fatty acid ester and / or a polyethylene glycol fatty acid ester, and a polyalkylmethacrylate are used as a base, which is a non-volatile organic liquid or a non-volatile organic liquid selected from hydrocarbons. The inventors have found that what is added is optimal, and finally completed the present invention.

That is, the present invention provides an ink backflow preventer composition for an aqueous ball-point pen, which is filled with an aqueous ink having a viscosity of 50 to 2000 CPS at 25 ° C. in an ink containing tube, wherein the ink backflow preventer composition is more than hydrocarbons. Characteristically based on selected non-volatile organic liquid or non-volatile organic liquid, to which gelling agent, glycerin fatty acid ester and / or polyethylene glycol fatty acid ester, and polyalkylmethacrylate are added The present invention is directed to a water-based ballpoint pen ink backflow preventive composition.

As the hardly volatile organic liquid or the non-volatile organic liquid selected from the hydrocarbons used as the base in the present invention, polybutene LV-100, HV-15 and HV-
35 (above, manufactured by Nippon Oil Co., Ltd., liquid harafin, α-olefin oligomer, spindle oil, vaseline, etc. are listed, and these can be used alone or in combination of two or more.

The gelling agent used in the present invention includes fine particle silica such as Aerosil (manufactured by Nippon Aerosil Co., Ltd.), hydrogenated castor oil-based one such as Disparlon 305 (manufactured by Kusumoto Kasei Co., Ltd.), and soroid (three). Cellulose-based products such as Akira Co., Ltd., metal soaps, bentonite and the like can be mentioned. If, for example, fine particle silica having a silanol group on the surface and a primary particle size of several mμ to 50 mμ is used as a gelling agent, a transparent feeling as an ink backflow preventive composition is produced, and the ink containing tube itself Also, if it is transparent, a product that looks good in appearance can be obtained.

The blending ratio of these gelling agents is preferably 1 to 20% by weight. When it is 1% by weight or less, the gelling strength of the ink backflow preventive composition becomes weak and the ink easily flows backward, and when it is 20% by weight or more, the gelling strength is too strong to follow the ink. There is a tendency for the sex to deteriorate.

Next, glycerin fatty acid ester and polyethylene glycol fatty acid ester, which are also the first additives of the present invention, will be described.

These additives are added to prevent the ink backflow preventive composition from adhering to the inner surface of the ink containing tube. At the same time, however, the ink is added even for fast writing such as a writing speed of 15 cm / sec. It is also possible to exhibit excellent followability capable of sufficiently responding to the consumption speed of. Specific examples thereof include glyceryl fatty acid ester such as glyceryl dioleate, glyceryl monoisostearate, glyceryl monocaprylate, and glyceryl monooleate, and polyethylene glycol fatty acid ester includes polyethylene glycol distearate and polyethylene glycol. Diisostearate etc. are mentioned. These may also be used alone or in admixture of two or more with the above-mentioned base.

Further, polyalkylmethacrylate which is the second additive of the present invention will be described. Polyalkylmethacrylate is added to prevent solidification of the network structure in the ink backflow preventive composition at low temperature and to maintain the same flow characteristics as at room temperature. No. 805, No. 806 (above, manufactured by Sanyo Chemical Industry Co., Ltd.) and the like, and these can be used alone or in combination of two or more as in the above.

The water-based ink to which the ink backflow preventive composition according to the present invention is applied has a viscosity of 50 to 2 at 25 ° C.
It is preferably 000 CPS. This is because the present inventors have a structurally simple point which is an advantage of the conventional oil-based ballpoint pen, and a vivid and vivid point which is an advantage of the conventional water-based ballpoint pen using an ink having an extremely low viscosity of several CPS. This is based on one finding that has been obtained after various studies to obtain a ball-point pen having both the points of handwriting.

(Examples) Hereinafter, the present invention will be described in more detail with reference to Examples. In the Examples, "part" means "part by weight".

Example-Polybutene HV-15 (manufactured by Nippon Oil Co., Ltd.) 89 parts-Aerosil R-972 (gelling agent, manufactured by Nippon Aerosil Co., Ltd.) 3 parts-Reopearl KE (gelling agent manufactured by Chiba Milling Co., Ltd.) ) 5 parts-Polyethylene glycol diisostearate (CDIS-400, manufactured by Nikko Chemicals Co., Ltd.) 1 part-Glycerin dioleate (DGO-80, manufactured by Nikko Chemicals Co., Ltd.) 1 part-Acluve 805 (polyalkyl) Methacrylate, manufactured by Sanyo Kasei Co., Ltd. 1 part The above composition was put in a kneader and heated and stirred for 2 to 3 hours to obtain an ink backflow preventive composition for an aqueous ballpoint pen.

Comparative Example An aqueous ink backflow preventer composition for an aqueous ball-point pen was obtained in the same manner as in the above-mentioned example except that the exclude 805 (polyalkylmethacrylate) was omitted.

(Effects of the Invention) Inks in which the ink backflow preventive compositions obtained in the above Examples and Comparative Examples are filled with a water-based ink having a viscosity of 250 CPS having the following composition, and a nickel-white ballpoint pen tip is attached to one end Storage tube (material: polypropylene, inner diameter:
3.2 mm) and the upper part of the ink was filled, and the spiral writing was performed 800 m at 0 ° C. under the conditions of 100 g of writing weight, a writing angle of 70 °, and a writing speed of 7 cm / sec.

The results are shown in the table below.

(Composition of water-based ink) Water black 187L (manufactured by Orient Chemical Industry Co., Ltd.) 8.0 parts Polyvinylpyrrolidone K-90 10 parts Ethylene glycol 15 parts Sannix PP-400 (Lubricant, manufactured by Sanyo Kasei Co., Ltd.) 10 Part Water 57 parts As is clear from the above description, according to the ink backflow preventive composition for an aqueous ball-point pen of the present invention, the use of an aqueous ink having a viscosity of 50 to 2000 CPS,
As the ink consumption is reduced, it does not adhere to the inner tube of the ink storage tube and reliably follows the ink and does not cause ink and ejection failure, and the ink backflow preventive composition may disappear during the process. Further, it has an excellent effect such that the problem of inability to write due to the solidification of the ink backflow preventive composition can be solved not only at room temperature but also at a low temperature environment.

 ─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-58-112798 (JP, A) JP-A-55-99166 (JP, A) JP-A-50-77405 (JP, A) JP-B-59- 11638 (JP, B1)

Claims (1)

[Claims] 1. A viscosity at 25 ° C. in an ink containing tube is 5
What is claimed is: 1. An ink backflow preventer composition for a water-based ballpoint pen filled with a water-based ink of 0 to 2000 CPS, wherein the ink backflow preventer composition contains a hardly volatile organic liquid or a non-volatile organic liquid selected from hydrocarbons. An aqueous ink composition for backflow prevention for ball-point pens, which comprises a base, and a gelling agent, glycerin fatty acid esters and / or polyethylene glycol fatty acid esters, and polyalkyl methacrylate added thereto.