JPS62104800A - Eraser for erasing water-color ink - 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 (Industrial Field of Application) The present invention relates to a water-based ink erasing eraser for erasing handwriting drawn on water-based ink on non-penetrating surfaces such as tracing paper and matte film. It is something.

(Prior art and its problems) Traditionally, as a method for erasing handwriting made with water-based ink on non-penetrating surfaces such as Tracing F Heber and matte processed films, erasers containing two particles of abrasive dispersed therein have been used. method by rubbing.

One method relies on so-called physical means, such as scraping off the handwriting with the edge of a cutter, and the other uses chemical means, in which the eraser contains a solvent that can dissolve the binder resin in the water-based ink, thereby dissolving and removing the handwriting. things are known.

However, methods that rely on physical means have the problem that the surface of the paper is often damaged when scratched, making it impossible to write on the area in the future, and methods that rely on chemical means Since the solvent that can dissolve the binder resin in water-based ink is generally a hygroscopic solvent such as ethylene glycol, diethylene glycol, triethylene glycol, etc., □1%.

8 months, 8 Ue'tP L d J-yotsuyuyo 49, 1
□□ The sweating phenomenon of adhesion occurs, and these droplets! Therefore, there is a problem that the eraser easily slips on the paper surface, making erasing impossible, or even staining the paper surface.

The present inventors investigated the cause of this sweating phenomenon based on the idea that chemical means are basically superior to handwriting erasing methods using water-based ink, and one finding was that It was concluded that the glycols mentioned above have a large hygroscopic property, so they absorb moisture in the air and expand their volume, and as a result, the moisture and these solvents adhere to the eraser surface in the form of droplets. reached.

(Failure to solve the problem) The present invention was made in view of this knowledge.

In order to prevent the above-mentioned sweating phenomenon as much as possible, we have conducted intensive research on the eraser base material, and have decided to use polyvinyl chloride and polyvinyl chloride-vinyl acetate copolymer together as the eraser base material, and to specify the ratio of their use. It was discovered that the intended purpose could be achieved by doing so, and was finally completed.

That is, the present invention provides a water-based ink erasing eraser containing a hygroscopic solvent, in which the base material of the eraser is made of polyvinyl chloride and a polyvinyl chloride-vinyl acetate copolymer, and the polyvinyl chloride-vinyl acetate copolymer is The gist of the present invention is an eraser for erasing water-based ink, characterized in that the weight ratio of the vinyl copolymer is 0.25 to 1.

The following five aspects of the present invention will be explained in detail.

Examples of the hygroscopic solvent in the present invention include those capable of dissolving the binder resin in the water-based ink as described above, and specific examples thereof include ethylene glycol, diethylene glycol, triethylene glycol, and the like. These solvents may be used alone or in combination of two or more, and the amount used is 5 to 50% by weight based on the total weight of the eraser.

Preferably it is 5 to 30% by weight.

The feature of the present invention is that two types of polyvinyl chloride and polyvinyl chloride-vinyl acetate copolymer are used together as a blank eraser base material containing the above hygroscopic solvent,
In addition, in these usage ratios, the weight ratio of polyvinyl chloride vinyl acetate copolymer to polyvinyl chloride is 4 to 0.
25 to 1, but this is due to the fact that when polyvinyl chloride is used alone as the eraser base material, the eraser itself contains many parts with low polarity.
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h k # jll n? There is a tendency for it to become difficult to be retained during M L°.

1 In addition, when polyvinyl chloride vinyl acetate copolymer is used alone as the eraser base material, many highly polar parts are generated in the eraser itself, resulting in the solvent being removed. .-1
[lKRu16□: Knowledge derived from both the fact that there is a tendency to 1 Yes,... Ah,. O, A, □Wa, E2□ By using the base materials in combination, a low polarity region and a high polarity region are suitably localized in the eraser.
This allows as much solvent as possible to be retained in the eraser and prevents sweating.

From these viewpoints, it is essential that the weight ratio of the polyvinyl chloride vinyl acetate copolymer to the polyvinyl chloride is 0.25 to 1. The amount of vinyl acetate in this polyvinyl chloride vinyl acetate copolymer is 1 to 15% by weight, preferably 5 to 10% by weight.

In the present invention, in addition to containing the above-mentioned solvent in the eraser, a super absorbent polymer substance or a water thickening/gelling polymer substance may be added as an antiperspirant, and if necessary, a filler, Flavoring agents and the like may be added.

That is, as super absorbent polymer substances, Sunwet 1 to 1-31-3O0, which are made of starch polyacrylate,
IM-1000MPS (The above is Sanyo Chemical Industries, Ltd.!
Riya, Sumikagel 5P-520 made of acrylic acid/vinyl alcohol copolymer, Sumikagel NP-1020C or more made of sodium acrylate polymer, Sumitomo Chemical ■
For water thickening and gelling polymeric substances, natural plant-based substances such as toshite, gar gum,
Seed polysaccharides such as roasted bean gum, quince seed gum, and tara gum; seaweed polysaccharides such as carrageenan, alginic acid, farcelan, and agar; resin polysaccharides such as arabinogalactan gum, gum arabic, gum tragacanth, and gum karaya; and fruit polysaccharides such as pectin. Sugars, supplements.

Examples include rhizome polysaccharides such as konnyaku and Japanese mallow.
Natural microbial products include xanthan gum, xancourt, xanfro, and curdlan.

Succinoglucan, 4271 gum, schizophyllan, etc. are available, natural animal products include gelatin, casein, albumin, shellac, etc., and semi-synthetic products include starch derivatives, gar gum, locust bee 7 gum, etc. Four kidnappers.

There are cellulose derivatives, alginic acid derivatives, etc.

Examples of synthetic materials include vinyl-based materials such as polyvinyl alcohol, polyvinylpyrrolidone, and polyvinyl methacrylate, acrylic-based materials such as sodium polyacrylate, and polyethylene oxide.

These highly water-absorbing polymeric substances and water thickening/gelling polymeric substances can be used alone or in combination of two or more, and the amount used is 7% or more by weight of the solvent, preferably 10% by weight or more.
Heavy food consumption% or more.

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

There are various methods for actually incorporating glycol-based solvents into erasers, but the following are five typical examples.
I will list and explain one. That is.

(2) After the plasticizer is gelled with a gelling agent, a solvent, the eraser base mentioned above, and a stabilizer are added thereto and uniformly dispersed and mixed to form a paste.

How to obtain erasers by heat molding.

■After adding a plasticizer and a stabilizer to the eraser base material prepared above to form a paste, powder method microcapsules containing a solvent as a core material are added to this, stirred and dispersed uniformly, and then heated and molded. How to get an eraser.

■＠Writable eraser After adding plasticizers and stabilizers to the base material to make a paste, inorganic powder adsorbed with a solvent is uniformly stirred and dispersed, and then heated and molded to obtain an eraser. Method.

It is.

Accordingly, in the present invention, a desired eraser is obtained by one or more of each method.

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

Example 1 Dioctyl phthalate (plasticizer) 150+li parts (hereinafter simply referred to as "parts") and gelling agent (Gelol D
, manufactured by Shin Nippon Rika Co., Ltd., was added and dissolved by heating, and then allowed to cool to obtain 155 parts of a gelled plasticizer. to this gelled material.

, diethylene glycol (solvent) 55 parts/polyvinyl chloride (Ge on 121).

Nippon Zeon Co., Ltd. 120 parts Polyvinyl chloride vinyl acetate copolymer (approx. 5% vinyl acetate, Denka Vinyl M-120. Denki Kagaku Kogyo ■) 30 parts Epoxidized soybean oil (stabilizer) 3 parts Calcium carbonate (
After adding 30 parts of filler and stirring and mixing uniformly, press molding was performed at 110 tons for 20 minutes to obtain an eraser.

Example 2 Production of microcapsules by powder bed method 70 parts of ethylene glycol and 45 parts of calcium carbonate were stirred and mixed to obtain 115 parts of a paste, which was stirred at high speed in 20 parts of ultrafine silica powder. 205 parts of silica wall microcapsules were obtained.

Manufacturing method of eraser> ・Polyvinyl chloride (Geon 121゜Nippon Zeon Co., Ltd.) 100 parts ・Polyvinyl chloride vinyl acetate copolymer (approximately 5% vinyl acetate, Denka Vinyl SM-160, Shiki Kagaku Kogyo I, manufactured by Kiki) ) 50 parts ・Dioctyl phthalate (plasticizer) 150 parts ・Epoxidized soybean oil (stabilizer) 3B5 ・Starch polyacrylate (super absorbent polymer material, sunwear) IM-1000MPS, Sanyo Chemical Industries (stock company) )
10 parts These components were stirred and mixed to obtain 613 parts of a paste-like material, and 205 parts of the above-mentioned microcapsules were added to this paste-like material and mixed with stirring.

1101S! Press molding was carried out for 20 minutes to obtain an eraser.

Example 6 Method for Producing Solvent-Adsorbed Inorganic Powder> 100 parts of activated clay was stirred at high speed, and 50 parts of triethylene glycol was added dropwise during stirring to obtain 150 parts of activated clay powder adsorbed with triethylene glycol.

Manufacturing method of eraser ・Polyvinyl chloride (Ge o n 121).

Nippon Zeon Co., Ltd. 75 parts, polyvinyl chloride vinyl acetate copolymer (about 10% vinyl 0 acid, Denka Vinyl MM-9014 Ki Kagaku Kogyo IJi Ri 75 parts, dioctyl phthalate (plasticizer) 150 parts, epoxy 3 parts of oxidized soybean oil (stabilizer), 10 parts of carrageenan (water thickening/gelling polymeric substance, GBNUVISGO O8W-1, manufactured by Sanhin@) These components were stirred and mixed to obtain 313 parts of a paste-like material. 150 parts of the activated clay powder described above was added to this paste and mixed with stirring, followed by press molding at 110 υ for 20 minutes to obtain an eraser.

As a comparative example, in Examples 1 to 3 above, the polyvinyl chloride vinyl acetate copolymer was removed and only 150 parts of polyvinyl chloride was used and an antiperspirant was added. Removal l Lf, it! +&f
Comparative Examples 1 to 5 were er-u1, to 68-1-e.

(Effect of the invention) Examples 1 to 6 above. The erasers obtained in Comparative Examples 1 to 6 were placed on a glass plate in a constant temperature and humidity chamber i (i) at a temperature of 50'C and a humidity of 80% and left for 3 days! However, with respect to the erasers of Comparative Examples 1 to 3, droplets were observed to adhere to the surface of the eraser, and so-called droplets were observed on the contact surface with the glass plate, but in the erasers of Examples 1 to 3)
Regarding this, no changes were observed. Also, Example 1
The eraser shown in Items 1 to 2 was able to successfully erase handwriting made with water-based pigment-based ink on Train Puffer Vapor, and it can be said that the eraser for erasing water-based ink according to the present invention is extremely valuable.

Claims (1)

[Claims] In a water-based ink erasing eraser containing a hygroscopic solvent, the base material of the eraser is made of polyvinyl chloride and a polyvinyl chloride-vinyl acetate copolymer, and the polyvinyl chloride-vinyl acetate copolymer is A water-based ink erasing eraser characterized by a weight ratio of 0.25 to 1.