JPS6330940B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention enables changing the pasting location and repeated pasting without using adhesives, and eliminates the appearance of pasting traces on the pasting surface after peeling off, and eliminates stains caused by pasting work. This invention relates to a vinyl chloride film that has a durable electrostatic adhesive force that can be pasted.

Conventional adhesion (adhesion) means mostly involve the use of adhesives. However, when pasting using an adhesive, it is difficult to peel off once it has been pasted, so it can only be used once, and the pasting location cannot be changed or the pasting cannot be repeated. Further, after peeling off, traces of pasting are left on the pasting surface, so there are disadvantages such as the troublesome cleaning process after use and restrictions on the place of use.

In view of these points, the present invention provides a vinyl chloride film that can be attached using electrostatic adhesive force, thereby solving the above-mentioned drawbacks.

It is well known that vinyl chloride films and sheets are triboelectrically charged and generate static electricity. Conventionally,
This problem is recognized as a static electricity problem, and the problem is mainly focused on preventing the generation of static electricity, and various antistatic measures including antistatic oil agents have been proposed.

However, the present invention actively utilizes the adhesive force caused by static electricity for pasting films, and is a completely new attempt never seen before.

Here, even if vinyl chloride films and sheets are triboelectrically charged and generate static electricity, the static electricity decreases over time and the adhesive force disappears, so they cannot be used as products as they are. In order to be used as a product, a large amount of static electricity must be generated, the static adhesive force must be strong, and the generated static electricity must not decrease over time and last for a long time, so research on new and unprecedented technology is required. It is.

In order for films and sheets to be able to retain a larger amount of charge than conventional tribostatic electricity, it is desirable that the charges not only exist on the surface of the film and sheets but also diffuse into the interior thereof. Also, in order to prevent static electricity from decreasing over time,
It is desirable that the charge be trapped by the film/sheet material. In other words, if the quantity of electricity easily penetrates and diffuses into the volume and is trapped at the diffusion position, the quantity of electricity per unit weight is becomes large, and because it penetrates and diffuses into the volume, the distribution state when viewed from the surface is closer to a uniform state than in the conventional case where only the surface is charged. Furthermore, since the charges trapped within the volume are in a kind of electret state, there is no fear that they will decrease over time.

Therefore, a promoting material that promotes the infiltration and diffusion of charges into the interior and a charge trapping material that prevents charges from being reduced due to the charges that have penetrated and diffused inside leaking out again are mixed into the vinyl chloride resin. if,
It is possible to produce films and sheets that have a much better sustained electrostatic adhesion than conventional ones. However, a material that promotes the infiltration and diffusion of charges into the interior naturally also promotes the leaching and diffusion of charges from the inside to the outside, and therefore does not provide long-term electrostatic adhesion. From this point of view, the material must be unidirectional, that is, a material that promotes intrusion diffusion similar to a rectification effect, but has a low percolation and diffusion ability, and has an excellent charge trapping ability. Expressed equivalently in terms of an electric circuit, the charges trapped inside form a capacitor across the adhesive surface, and the insulation resistance of the capacitor must have rectifying resistance characteristics.

The inventor of the present invention has made this invention as a result of intensive research from this point of view, and its gist is that an organic ketone having a carbon number of 40 to 60 is blended in a range of 1 to 3% by weight based on vinyl chloride. That is.

Because they are vinyl chloride films and sheets, even if they are manufactured without using any materials that have an antistatic effect, for example, plasticizers may or may not have antistatic ability, or they may generate charges. However, those with antistatic ability should be excluded and those with charge generation ability should be actively used. Molecules containing metal molecules, metal complexes of polyvinyl chloride, metal-crosslinked organic medium molecules such as polySchiff bases, medium molecules with coordination bonds such as squaric acid metal complexes, chelate-type medium molecular weight complexes, metal cyano complex medium molecules, vinylpyri Dium ester,
Even when manufactured by blending mixed medium-molecular compounds such as polyvinylpyridium salts and phthalocyanine salts, parquet-like medium-molecular compounds such as pyromethonitrile derivatives, pyromellitic acid derivatives, and polytetracyanoethylenes, the charge remains unchanged. This is sufficient from the standpoint of electrostatic adhesion, as it is generated in large quantities and the electrostatic adhesion becomes strong, but the reason why the present invention incorporates an organic ketone with a carbon number of 40 to 60 further increases the charge trapping ability. It promotes charge penetration and diffusion, forms a unidirectional charge transfer layer on the film surface, especially on the friction surface of the film, maintains static electricity for a long time, and has high compatibility with vinyl chloride resin, which allows charge to spread evenly within the volume. This is to improve the dispersibility within the resin.

Here, we limited the organic ketones to those with a medium molecular weight of 40 to 60 carbon atoms because if the number of carbon atoms is less than 40, the organic ketone will precipitate and separate. This is because the molecular weight becomes too large, making it difficult to mix uniformly when mixed. Furthermore, if the blending ratio of organic ketone is less than 1% by weight, the charge trapping ability will be insufficient, and if it exceeds 3% by weight, the mechanical properties of the vinyl chloride film will become weak and it will be easy to stretch and wrinkle, which is not preferable. .

The thickness of the vinyl chloride film is preferably in the range of about 20 to 450 μm, because if it is too thin, it will wrinkle more easily and be difficult to peel off, and if it is too thick, it will be difficult to adapt to the surface to which it is attached.

The organic ketone is preferably a modified ketone derived from a metal stearate, such as magnesium stearate or calcium stearate. A modified ketone derived from magnesium stearate is produced through the following reaction process.

Stearic acid (melting temperature approx. 55℃) 100Kg at 150℃
The molten stearic acid is melted in a heated melting tank nearby, and 5 kg of caustic magnesia powder is sequentially added from above at a rate of 50 to 100 g at a time while stirring the stearic acid. At the beginning of charging, magnesium stearate is produced by the reaction between caustic magnesia and stearic acid, and the melting point increases. For this reason, the melting tank continues to be heated to maintain it at around 150°C. Modified stearin is matured in a reaction time of approximately 15 minutes.

One purpose of adding caustic magnesia is to use it as a reaction raw material for magnesium stearate, and another purpose is to use it as a catalyst for converting magnesium stearate into modified ketonization. Although magnesium stearate does not undergo thermal decomposition, it is necessary to maintain the temperature around 150°C so that the reaction proceeds quickly.

Once the modified stearin has been aged, 10 kg of fuming concentrated hydrochloric acid is continuously flowed into the tank while stirring, and a contact reaction is carried out for about 10 to 15 minutes to produce organic ketones with carbon numbers of 40 to 60. Obtained. Since this organic ketone contains a large amount of by-products and magnesium chloride, it is necessary to remove water-soluble components through several washings with boiling water. In addition, water-insoluble components of small molecular weight that are produced as a by-product are removed together with low-boiling components by fractional distillation in a vacuum distillation tank. As a result of the above, 60 kg of the target product was obtained.

Next, the modified ketone obtained in this way is
It was blended in an amount of 2% by weight based on vinyl chloride, mixed uniformly, and formed into a film to obtain the vinyl chloride film imparted with electrostatic adhesion according to the present invention.

Therefore, the vinyl chloride film according to the present invention has a strong electrostatic adhesive force that lasts for a long time, so it can be used on any suitable flat surface, such as a window surface, a wall surface, a rocker, etc.
It can be attached to furniture, desks, bookshelves, etc. with static electricity, and the attachment location can be changed and the attachment can be used repeatedly. Moreover, the vinyl chloride film according to the present invention does not leave any traces of pasting after being peeled off.

Therefore, the present invention is applicable to products that are used by pasting, products that are used by pasting and peeling, for example,
It is ideal for use as paper for advertisements and guidance, as a substitute for blackboards, bulletin boards, and message boards, as memo paper, as stickers for various types of games, etc. At this time, it is of course necessary to process each material according to the material to be used. For example, the surface of the film may be printed or pasted, or pigments may be mixed and colored during production.

The test results of the charging characteristics of the vinyl chloride film according to the present invention were as follows.

50μ thick film 900mm x 600mm and 200mm x 400
mm in size, with five colors printed on the surface, was rubbed against a vertically placed metal plate in an environment of temperature 5-28℃ and humidity 20-73%, and was electrostatically attached on January 20, 1981. When the adhesive was left as it was and the progress was observed, it was found that it was still attached as of August 8, 1982, and was continuing to adhere, confirming that it had a long-term electrostatic adhesive force.

Claims (1)

[Claims] 1. A vinyl chloride film characterized in that it is blended with an organic ketone having 40 to 60 carbon atoms in a range of 1 to 3% by weight based on vinyl chloride to impart sustainable electrostatic adhesion.