JPH0784120B2 - Eraser with abrasive - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an eraser containing an abrasive, and particularly to an ink such as an image formed by printing with high-viscosity ink, handwriting with an oil-based ballpoint pen, or electrostatic copying. The present invention relates to an eraser containing an abrasive, which is suitable for erasing handwriting and images on the surface layer of paper in which toner and toner do not penetrate into the fibers of the paper.

(Prior art and its problems) In general, the surface of paper has unevenness due to the interweaving of paper fibers, and the printed image of highly viscous ink, the handwriting with an oil-based ballpoint pen, and the image formed by the electrostatic copying method. Even though the ink and toner did not penetrate into the inside of the paper fiber, they entered into the unevenness of the paper surface, so it could not be erased with an ordinary pencil eraser.

Therefore, in order to erase these images and handwriting, a method has been adopted in which an eraser containing an abrasive material called an sand eraser is used to rub the area to remove the fibers on the paper surface, which erases it. Since the eraser base material has rubber properties, the problem of deterioration of erasability due to deterioration of the base material cannot be avoided. Therefore, in recent years, it has been considered to use a thermoplastic resin base material that does not deteriorate with time. Has been done.

However, when an eraser containing this thermoplastic resin as a base material contains an abrasive, the adhesive is not securely fixed in the eraser due to insufficient adhesion between the abrasive and the base material, and therefore the abrasion Although the abrasive was caught on the paper fiber at the time of erasing, it was detached from the eraser without stripping the fiber, and as a result, the erasing performance was not satisfactory.

(Means for Solving Problems) In order to solve such a problem, the inventors focused their attention on the abrasive material in the eraser containing the abrasive material, and conducted various studies on the eraser material. In the case of a thermoplastic resin, if the surface of the abrasive is treated with a coupling agent such as silane or titanium, the adhesion between the base material and the abrasive will be particularly good, and its erasing performance will be remarkable. The inventors have found that they are improving and have completed the present invention.

That is, the gist of the present invention is an eraser containing a thermoplastic resin as a base material, in which the eraser contains an abrasive whose surface is treated with a coupling agent.

Hereinafter, the present invention will be described in detail.

Examples of the abrasive used in the present invention include those which have been conventionally used, specifically, glass powder, carborundum, silica sand, etc., and the average particle size is 10
It is preferably about 200 μm. The average particle size of the abrasive is 10μ
If it is smaller than m, the paper surface cannot be peeled off due to the polishing effect, and if it is larger than 200 μm, the paper surface is damaged more than necessary.

Thus, the surface of these abrasives is treated with a coupling agent. There are several types of coupling agents such as titanium-based, silane-based, and aluminum-based, specifically titanium-based. As isopropyl triisostearoyl titanate, isopropyl tridodecylbenzene sulfonyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, etc., and as silane-based compounds, γ-aminopropyltriethoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, etc. can be used. Is.

When actually treating the above-mentioned abrasive with a coupling agent, the following three methods can be generally adopted. That is, the integral blend method: a method of adding a coupling agent directly or in a state of being appropriately dissolved in a plasticizer when an abrasive is mixed with a paste material that is a base of an eraser.

Dry pretreatment method: A method in which a coupling agent is dissolved directly or in a small amount of an appropriate solvent and then dropped or sprayed onto an agitated abrasive.

Wet pretreatment method: A method of dissolving a coupling agent in a large amount of an appropriate solvent, stirring and mixing this with an abrasive, distilling off the solvent, and then removing by drying.

Is.

The amount of the coupling agent used is preferably 0.5 to 1.0% by weight based on the total weight of the abrasive in order to obtain good adhesion between the eraser base material and the abrasive.

Needless to say, various solvents capable of dissolving handwriting and images, other fragrances, fillers and the like may be appropriately added to the eraser containing the abrasive according to the present invention.

(Function) In the present invention, the surface of an abrasive in an eraser base material made of a thermoplastic resin, preferably polyvinyl chloride or a copolymer of polyvinyl chloride and polyvinyl acetate, is treated with a coupling agent. Therefore, since the organic substance in the coupling agent is strongly bonded to the eraser base material in which the organic substance is organic, and the inorganic substance is strongly bonded to the abrasive substance in which the inorganic substance is organic, the detachment of the abrasive substance during the eraser scratch erasure is prevented as much as possible, In the end, the advantages of the eraser based on the thermoplastic resin can be utilized.

(Examples) Hereinafter, the present invention will be described in detail based on Examples.

Example 1 <Method for producing abrasive> Natural shirasu (abrasive, particle size: 100 μm) 100 parts by weight Isopropyltriisostearoyl titanate (TTS2-3099, titanium coupling agent manufactured by Ajinomoto Co., Inc.) 1 part by weight n− Hexane 10 parts by weight Isopropyltriisostearoyl titanate is dissolved in n-hexane and added dropwise to stirring natural shirasu powder for about 5 minutes, then stirring for about 5 minutes and then in an oven at 100 ° C for 2 hours. An abrasive A was obtained by drying. (Dry pretreatment method) <Method for producing eraser> Polyvinyl chloride (Geon, 121, manufactured by Nippon Zeon Co., Ltd.) 150 parts by weight Dioctyltin carboxylate stabilizer (TN-800, manufactured by Sakai Chemical Industry Co., Ltd.) 4 parts by weight Dioctyl phthalate (plasticizer) 105 parts by weight Abrasive A 60.4 parts by weight These components are uniformly mixed by stirring to form a paste-like product 319.4.
By obtaining parts by weight, press molding was performed at 110 ° C for 20 minutes to obtain an eraser containing an abrasive.

Example 2 <Manufacturing method of abrasive> Natural shirasu (particle size: 100 μm) 100 parts by weight γ-aminopropyltriethoxysilane (KBE903, silane coupling agent manufactured by Shin-Etsu Chemical Co., Ltd.) 1 part by weight n-hexane 100 parts by weight γ-aminopropyltriethoxysilane is dissolved in n-hexane, natural shirasu is added thereto, and the mixture is stirred for 15 minutes.
Then, transfer this to a vat and place on a hot plate 70
Abrasive B was obtained by drying at 45 ° C. for 45 minutes and further at 110 ° C. for 5 hours in an oven. (Wet Pretreatment Method) <Eraser Manufacturing Method> Using the above abrasive B, an eraser containing an abrasive was obtained in the same manner as in Example 1.

Comparative Example In the method for producing an eraser of Example 1, the abrasive A was treated with a natural shirasu (particle size 10
The eraser-containing eraser was obtained in the same manner as in Example 1 except that the eraser was changed to 0 μm).

(Effects of the Invention) Using the eraser obtained in Examples 1 and 2 and Comparative Example above, the handwriting with a commercially available oil-based ballpoint pen drawn on high-quality paper was scratched and erased. Although it was possible, the abrasive easily detached from the base material and the eraser became brittle, while the ones of Examples 1 and 2 could be erased faster than the comparative example, and there was almost no detachment of the abrasive, which was good. It showed a good result.

As described above, the eraser containing an abrasive material according to the present invention makes use of the fact that the characteristics of the thermoplastic resin do not deteriorate with time, and prevents the abrasive material from being detached from the base material, thereby providing a better erase performance. It is something to demonstrate.

Claims (1)

[Claims] 1. An eraser containing a thermoplastic resin as a base material, wherein the eraser contains an abrasive whose surface is treated with a coupling agent.