JPS61222798A - Eraser for compensating electrostatic process copying picture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an eraser for correcting images formed by electrostatic copying.

(Prior art and its problems) In recent years, electrostatic copying has come to be used to create industrial drawings. It is increasingly being used as a second original drawing on which an image is formed on a drafting film.

Images were formed on plain paper such as tracing paper and drafting film by electrostatic copying.

Since the so-called second original image is composed of two images that are fused and fixed together with colored synthetic resin powder called toner, it is often impossible to correct it by simply using an eraser.

Conventionally, such correction of the second original image has been carried out by applying a toner solvent directly to the corrected portion of the image, dissolving the toner, and then wiping it off.

As a toner solvent, it dissolves toner well.

Chlorinated hydrocarbons such as benzene, toluene, xylene, aromatic hydrocarbons, and trichlorethylene as a melt-fixing agent for toner; in addition to these, esters, ketones, aliphatic hydrocarbons, etc. may be used singly or appropriately. are used in combination.

However, in this method, after the toner is dissolved, it is wiped off, so a solvent with good solubility is used on both sides of the paper.

It has a tendency to stain the film surface.

In addition, in order to reduce staining, water or lower alcohols were mixed with ketones, ethers, and esters that are compatible with water or lower alcohols. Using a solvent (Special Publication No. 48-35420
No.) There are examples.

Low boiling point, volatile solvents are used to shorten the drying time after correction. For this reason, the correction operation had to be performed quickly, and it could not be called an easy correction method.

Furthermore, since the solvent is applied directly to the two images, it is impossible to correct general paper such as high-quality paper whose fibers are not dense because the dissolved toner penetrates into the fibers of the paper.

(Means for Solving the Problems) In view of these circumstances, the inventors of the present invention believe that if it is possible to find a substance that has particularly excellent solubility among toner solvents and incorporate it into an eraser, the above-mentioned solution will be achieved. As a result of intensive research, the present invention was finally completed based on the viewpoint that the problems associated with the invention would be solved.

That is, the present invention provides an eraser for electrostatic copying image correction characterized in that a powder bed process microcapsule having a core material of continuous porous cellulose acetate butyrate impregnated with a solvent represented by the following general formula is contained in an eraser. The gist is an eraser.

(General formula) (In the formula, R1=H, 02H5, R2=H, 02H5) The present invention uses the solvent shown in the above general formula, which exhibits particularly excellent solubility among solvents for dissolving toner, in the form of a continuous porous body. Since the powder microcapsules impregnated with cellulose acetate butyrate and using this as a core material are contained in the eraser, the solvent does not come into direct contact with the paper or film surface, thereby eliminating the need for 92 sheets of paper.

Not only does it not stain the film surface, but since the solvent is contained in the eraser as a liquid, the excellent solubility of the solvent itself is fully utilized for the two images. An eraser exhibiting excellent erasability will be obtained.

In the present invention, the reason why the toner solvent can be contained in the eraser as a liquid is that when the cellulose acetate butyrate is heated and dissolved in this solvent and then cooled, the cellulose acetate butyrate precipitates out and the solvent is impregnated with the solvent. A porous body is formed,
This is because this continuous porous body becomes a core material and is microencapsulated. Note that the solvent shown in the above general formula must have a relatively high boiling point.

It also has other advantages as an eraser, such as excellent stability over time and the ability to minimize odors during use.

Hereinafter, one aspect of the present invention will be explained in detail.

Solvents for dissolving toner contained in powder bed microcapsules, which are excellent in terms of simplicity and mass production, are those shown in the general formula below, and specific examples thereof are shown in the table below. (General formula) (In the formula, R1=H, 02H5R2=H, 02H5 (the above,
These solvents can be used alone or in a mixture of 2a or more, and the amount used is 5 to 50% by weight, preferably 5 to 50% by weight based on the total amount of the eraser.
~30% by weight.

Cellulose acetate butyrate, which is impregnated with a solvent that dissolves the toner and becomes the core material of powder microcapsules, is a mixture of esters of acetic acid, butyric acid, and cellulose. Specific examples thereof include Serifto BP300. BP50
0. BP700/25°BP700/40. B.P.
900 (above, Sumitomo Bayer Urethane ■ back), etc.

These cellulose acetate butyrates can be used alone or in combination.
The amount used is 5 to 20% by weight, preferably 10 to 20% by weight based on the solvent.
becomes. If the amount of cellulose acetate butyrate is less than 5% by weight based on the solvent, the continuous porous body made of cellulose acetate butyrate will not be integrated, and the solvent will not be completely impregnated into the continuous porous body.

If it exceeds % by weight, the continuous porous body is too strong and the impregnated solvent cannot be leached out from the porous body, which is not good.

Next, the method for producing the eraser according to the present invention will be briefly described.

First, cellulose acetate butyrate is added to a solvent and dissolved by heating.

If this solution is stirred at high speed in, for example, ultrafine powdered silica powder according to a conventionally well-known method, the solution surrounded by silica walls will cool, cellulose acetate butyrate will precipitate, and continuous pores impregnated with the solvent will be formed. A body is formed. Then, this continuous porous body is impregnated with a solvent in a liquid state to obtain silica-walled microcapsules serving as a core material. Incidentally, here, t of the solvent mentioned above
is adjusted to be 60 to 75% by weight based on the total amount of microcapsules. Next, a plasticizer is added to a conventionally known eraser base material, particularly preferably polyvinyl chloride or a copolymer of polyvinyl chloride and polyvinyl acetate.
Stabilizers, fillers and, if necessary, pigments.

A paste made by adding fragrances, abrasives, etc.
Add the powder method fibrocapsules mentioned above, disperse them uniformly, and then heat mold them.

The desired eraser can be easily obtained.

(Example) The present invention will be described in detail below based on two examples.

105 parts by weight (hereinafter simply referred to as "parts") of diethyl diphenyl (manufactured by Nippon Ritetsu Kagaku Kogyo ■, Allocizer 404), cellulose acetate butyrate (Sumitomo Bayer urethane FMM, 19 parts of BP500) were heated and dissolved to make solution 1.
24 parts were obtained, and this was stirred at high speed in 30 parts of ultrafine silica powder to obtain silica wall microcapsules.

Eraser manufacturing method> Polyvinyl chloride (made by Nippon Zeon ■, Gtbn121)!
li 50 parts dioctyl 7 tart (plasticizer) ?
155ffi parts epoxidized soybean oil (stabilizer)
5 parts Calcium carbonate (filling side) 10 parts The above ingredients were stirred and mixed to obtain 315 parts of a PVC paste-like material,
In addition to this, silica wall microcapsules 15 made by the powder bed method
After adding 4 parts and stirring and mixing uniformly, press molding was performed at 110° C. for 20 minutes to obtain an eraser.

(Effects of the Invention) Images formed by electrostatic copying on tracing paper and drafting film were rubbed five times with the eraser obtained in the above example.

In both cases, the images could be easily erased and corrected, and no smudges were seen in the corrections.

As described in detail above, the two erasers for electrostatic copy image correction according to the present invention exhibit excellent erasability.

What's more, there are no stains visible on the repair marks either.

An excellent eraser that can be used on general paper, such as high-quality paper that does not have dense fibers, because the solvent that dissolves the toner is absorbed by the eraser waste, so the solvent that dissolves the shear toner does not penetrate into the paper and cause problems. It can be said that.

Claims (1)

[Scope of Claims] An electrostatic copying image correction device, characterized in that an eraser contains powder-processed microcapsules whose core material is cellulose acetate butyrate in the form of open pores impregnated with a solvent represented by the following general formula. eraser. (General formula) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R_1=H, C_2H_5R_2=H, C_2H
＿５)