JPS5953199B2 - eraser - Google Patents

Description

[Detailed Description of the Invention] The present invention is applicable to the handwriting of a pencil written on paper, tracing paper, or drafting film, especially the handwriting of a drafting lead or colored pencil, or the handwriting of a sheet paper such as tracing paper or drafting film. The present invention relates to an eraser effective for erasing handwriting of oil-based and water-based inks.

Conventionally, solid erasers made of rubber or plastic have been used to erase pencil handwriting.

This is based on the principle that dust is created by rubbing the paper surface, and when the adsorption of the dust exceeds the adsorption of carbon, etc. from a pencil to the paper surface, the dust is erased.

To erase it well, you need to rub it repeatedly many times.
This resulted in disadvantages such as damage to the paper surface and an increase in eraser waste.

Also, there are correction fluids that erase handwriting with a liquid, such as ink erasers, but since this is a liquid, it flows to adjacent handwriting and erases areas that do not need to be erased. This may cause inconveniences such as smudging or smearing on the boundary surface of the erased area, or the need to absorb it with filter paper or blotting paper after erasing, which requires double effort.

Furthermore, the sand eraser used to erase handwriting made with oil-based or water-based ink is clearly erased by tearing off the paper surface, and it often smudges when rewritten with ink.

Furthermore, the lead of a pencil is made by hardening a carbon black pencil with clay or synthetic resin, and has the disadvantage that if you write on the paper and then rub it with your hand, the carbon etc. will rub off and stain the paper.

In particular, pencils are absolutely indispensable in the field of drafting, and staining the drawings has been a big problem, but in recent years, drafting leads, especially tracing paper for drafting and drafting film, have a tendency to adhere to paper surfaces. There are refills for pencils and sharpeners with good quality that do not stain the paper surface even when rubbed by hand, and they have been widely used.

However, due to its good adhesion, there is currently no eraser that can completely erase the handwriting of this type of drafting lead if you want to make corrections later. There is a strong desire for

SUMMARY OF THE INVENTION An object of the present invention is to provide an eraser that overcomes the above-mentioned drawbacks of conventional erasers.

The present inventors have finally completed the present invention as a result of intensive research to achieve the above object.

That is, the present invention consists of an eraser made by blending room-temperature curing silicone rubber that hardens by reacting with moisture in the air into an eraser base material made of rubber or plastic into which an eraser has been kneaded.

When this eraser is used to erase handwriting by rubbing, a thin film of silicone rubber is formed only on the surface of the eraser that is exposed to the air, and this film prevents the eraser that newly appears due to the rubbing from escaping.

Furthermore, since only the required amount of erasing liquid leaches out onto the rubber surface by rubbing, there is no need for unnecessary bleeding into adjacent areas.

The eraser used in the present invention includes 2-ethoxyethyl acetate, diethylene glycol monoethyl ether acetate, triethylene glycol monomethyl ether acetate, tetrafluoropropanol, hexafluorobutanol, morpholine, N-methylmorpholine,
Diethyl diisobutyl adipate malonate, N-β hydroxyethylacetamide, N-methylformamide cyclohexane, tetrachlorethylene, isopropyl alcohol, tetrahydrofuran, 1,4-dioxane,
Methyl ethyl ketone, ethyl acetate, amyl acetate, N-butylamine, cyclohexylamine, nitromethane, tetrahydrofurfuryl alcohol, methyl lactate, diethylene glycol monomethyl ether, epichlorohydrin, hexamethylphosphoramide, penzalpine,
Examples include ethyl orthosilicate/N-methyl 2-pyrrolidone.

In addition, the silicone rubber used in the present invention is one-component type (7
) RTV (Room TemperatureVul
canizφtion) silicone rubber, and the vulcanization mechanism is available in deacetic acid type, deamine type, dealcohol type, and deoxime type, each of which can be selected depending on the application.

Next, regarding the method for manufacturing the eraser of the present invention, the rubber base material, eraser, RTV silicone rubber, and other compounding agents can be kneaded together and molded. In this case, all the compounding agents, eraser, and other compounding agents are mixed. It must be dehydrated, and both mixing and molding must be carried out quickly and continuously so that it does not come into contact with moisture, and that exposure to the atmosphere is short-lived.

In addition, the erasing liquid may be used as is or only one type, or two or more types may be mixed in an appropriate ratio, or a solvent such as a ketone or ester that will not damage the drawing film or paper may be used. It may also be prepared by dissolving it so that it contains at least 60% by weight.

Incidentally, in any case, a fragrance or the like may be added to impart a preferable fragrance.

In addition, in order to increase the stability of the eraser in the direction of the eraser, it is effective to gel the eraser, and Aerosil is an example of such a gelling agent.

The one-component RTV silicone rubber compounded in the eraser is cured by the following reaction in the case of acetic acid-removed amyloxysiloxane, for example.

When a material that hardens due to moisture in the air is added to an eraser as shown in the above formula, only the surface of the eraser that is exposed to the air will harden, and once a thin film is formed, the inside will be cut off from the air. Therefore, the coating has a constant thickness, and this coating prevents the erasing fluid kneaded into the eraser from escaping.

When erasing, the coating is removed by rubbing the handwriting with another paper surface, and new eraser is constantly supplied onto the handwriting to be erased, which, combined with the effect of the eraser itself, facilitates erasing.

In addition, after erasing, the scraped part of the eraser coating is released into the air, so it reacts with moisture in the air again, forming a one-component RTV silicone rubber coating, which gradually removes the eraser. divergence is hindered.

As can be seen from the above explanation, the eraser of the present invention contains an eraser that dissolves drafting lead, colored pencils, and the binder binder for oil-based and water-based inks. It exhibits extremely excellent erasing performance because it removes debris along with it.

Furthermore, the eraser of the present invention is coated with one-component RTV silicone rubber, and the film prevents the eraser from transferring, so that the eraser does not reach the surface of the eraser as if it were simply placed in the eraser. It has the advantage that it does not migrate and emanate, and does not stain pencil paint or plastic containers.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example Geon 121 100 parts by weight (polyvinyl chloride paste resin, manufactured by Nippon Zeon Co., Ltd.) DOP (plasticizer) 80 parts by weight Calcium carbonate 15 Tori Ronos KA-20 (titanium oxide, manufactured by Titanium Kogyo Co., Ltd.) n MARK 5C-32 (Stabilizer, manufactured by Adeka Argus Chemical Co., Ltd.) JT The above components were mixed in a homomixer, and 60 parts by weight of N-methylformamide (Aerosil #
200 (manufactured by Nippon Aerosil Co., Ltd.) gelled with 5 parts by weight), then one-component RTV silicone rubber DC-7
80 (manufactured by Dow Corning) was added and mixed well.

The above mixture was molded under press conditions at 120° C. for 10 minutes to obtain an eraser.

Drafting film coated with thermosetting resin (made by Somar Kogyo, Neo Art) and refill for drafting [Pentel]
When an attempt was made to erase the handwriting written with the polyfit core P-1 (diameter: 0.9 m/m, manufactured by Manufacturer Co., Ltd.) by rubbing it several times with the eraser, the handwriting completely disappeared.

Further, the surface of the drawing film was not damaged or stained after erasing.

When I wrote again after erasing it, I was able to write again without any change from the original paper.

As a comparative test, an attempt was made to erase the exact same handwriting as in the example by rubbing it hard several times using a commercially available plastic eraser, but the handwriting remained thin and could not be completely erased.

Furthermore, this eraser had similar erasing performance even after being left at room temperature for 3 months.

Claims (1)

[Claims] 1. An eraser characterized in that an eraser base material made of rubber or plastic into which an eraser has been kneaded is blended with room-temperature curing silicone rubber that hardens by reacting with moisture in the air.