JPH0445902Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] Currently, overhead projectors are widely used for explanation purposes at conferences and the like.

The present invention relates to a projector sheet on which explanatory characters and figures are written and placed on the light source of the projector.

More specifically, the present invention relates to a projector sheet that has excellent writing properties, is easy to handle like paper, and has good antistatic properties.

[Prior Art] Conventionally, as a sheet for a projector, for example, a polyester sheet is written with oil-based ink and used as an original projection image for a projector.

When writing on such sheets, writing tools are limited to oil-based ink, and when writing with water-based ink, pencil, ink, etc., the ink may run or the pencil may not stick on the sheet.

In addition, conventional projector sheets do not separate when stacked in large numbers due to the adhesiveness, adhesion, and chargeability of the plastic film itself.
One drawback of projector sheets was that they could not be folded like paper when projecting images or organizing them before and after projection.

For example, dropping a stack of multiple projector sheets vertically onto a desk and aligning the edges is often done with paper sheets, but this is not possible with projector sheets.

Furthermore, conventional sheets have the disadvantage that they tend to attract stains such as fingerprints, and the stains are magnified and projected as they are.

[Problems to be Solved by the Invention] It is an object of the present invention to provide a projector sheet that eliminates the above three drawbacks and is convenient to handle.

[Means for Solving the Problems] As a result of intensive research into a method to eliminate the above-mentioned drawbacks at once, the inventor of the present invention discovered a method of applying a resin liquid in which inorganic powder is dispersed and forming an antistatic agent layer by a specific method. We solved this problem and came up with the present invention.

That is, the present invention provides antistatic particles suspended in the gas phase as fine particles on both or one side of a laminate of a transparent or translucent plastic sheet 2 and a resin layer 3 containing a dispersed inorganic powder for surface roughening. The present invention provides a projector sheet that has been subjected to antistatic treatment by being exposed to a chemical atmosphere.

The transparent sheet used in the present invention can be any transparent or translucent sheet, such as thermoplastic resins such as polyester, nylon, polyacetal, polycarbonate, polypropylene, and polystyrene. A transparent or translucent resin sheet can be used.

The projector sheet of the present invention has a resin layer formed by coating a transparent or translucent sheet with a resin liquid in which colorless inorganic powder such as silica, glass powder, mica, etc. is dispersed, and drying the resin liquid. Manufacture a laminate.

The resin liquid containing dispersed inorganic powder can be used, for example, in a resin liquid used for printing ink or paint, such as a solution of urethane-based, polyester-based, or polyamide-based resin, or in a two-component curing type or a crosslinked curing type. It is possible to use a resin liquid in which inorganic powder is dispersed.

However, it is preferable that these printing inks and paints do not contain pigments that are normally used in paints. At the very least, no pigment should be added that would make the character figures unclear during projection.

This resin liquid can be conveniently applied by the same method as printing.

It is also possible to use a laminate of resin layers in which inorganic powder is dispersed not only on one side but also on both sides of a transparent or translucent base sheet.

A sheet made of laminated resin layers in which inorganic powder is dispersed has an uneven surface, has a rough feel, and forms a surface with significantly improved writing properties.

Conventional projector sheets made of polyester can only be written on with oil-based ink, and cannot be written on with water-soluble ink, let alone pencils, but the inorganic powder of the projector sheet of this invention is dispersed. Water-based inks, pencils, etc. can also be used on the resin layer.

As an inorganic powder-dispersed resin liquid suitable for the water-based ink used in the projector sheet of the present invention, a two-component curing vinyl urethane resin with inorganic powder dispersed therein, for example, a product name manufactured by Osaka Printing Ink Manufacturing Co., Ltd. When using NRX, water-soluble ink transfers very well, and it also has excellent heat resistance, so it can withstand high heat during long-term projection.

Since the inorganic powder-dispersed resin layer of the present invention has exposed inorganic powder on its surface, it is rough as described above and does not have the surface tackiness characteristic of plastic film.

The projector sheet of the present invention does not create a vacuum state between the sheets even when many sheets are stacked, so it is easy to peel off, and the surface of the plastic sheet is covered with an uneven surface on which rough inorganic powder is dispersed. Therefore, the inherent surface tackiness of the plastic sheet can be reduced.

The plastic sheet of the present invention can be further treated with antistatic treatment to make it easier to handle and to prevent dirt from adhering to it.

However, simply applying an antistatic agent will not
The application may fill in the finely uneven surfaces, impairing the writability of the inorganic dispersed resin layer that has been painstakingly provided.

According to the method for applying the antistatic agent used in the present invention, the raw material of the laminated sheet is continuously supplied into an atmosphere in which it is stably dispersed as ultrafine particles in the gas phase using an ultrasonic nozzle or the like. , the antistatic agent can be applied uniformly and very thinly and continuously to the surface in contact with gas.

Such an antistatic treatment method can be carried out using a commercially available MDC antistatic treatment system manufactured by Tokyo Copal Chemical Co., Ltd.

According to such a method of contacting an antistatic agent in a gas phase atmosphere, the antistatic agent can be applied with a very thin coating film, for example, 0.01 to 0.02μ thick, so that the antistatic agent can be applied to the surface by dispersing inorganic powder. Even if the antistatic treatment is applied to a surface with minute irregularities,
Since the antistatic agent can be applied while maintaining the unevenness, the writability of the surface does not deteriorate.

In addition, products that have been subjected to antistatic treatment using a method such as the MDC method have the advantage that, because the antistatic agent layer itself is thin, it does not become sticky, unlike conventional antistatic agent coating treatments.

Any antistatic agent used in the present invention can be used as long as it can reduce the surface resistivity, but examples include anionic activators, cationic activators, and nonionic activators. Commercially available products can be used.

The present invention will be explained by way of examples.

In the projector sheet 1 shown in FIGS. 1 and 2, a resin layer 3 in which inorganic powder is dispersed in a polypropylene sheet 2 is laminated on one side of the sheet 2.

The inorganic powder dispersed in the resin layer 3 creates fine irregularities on the surface and usually becomes cloudy, making the sheet translucent.

The degree of cloudiness increases as the content of the inorganic powder increases, but some degree of cloudiness does not reduce the clarity of the image projected by the projector.

In addition, this white turbidity is determined by matching the refractive index of the inorganic powder material and the refractive index of the resin material as much as possible.
For example, by reducing the difference in refractive index to 0.2 or less,
Even if the content of the inorganic powder is increased, the transparency can be prevented from decreasing too much.

Furthermore, a coating film 4 of an antistatic agent applied by antistatic treatment by the MDC antistatic treatment system is attached to both surfaces.

The antistatic treatment used in the present invention consists of a spray chamber 7 in which ultrafine particles of an antistatic agent produced by an ultrasonic nozzle are stably dispersed in a gas phase, as shown in Figure 3. Fine particles of antistatic agent are uniformly adhered to the surface of the Ector sheet through the original sheet. The antistatic agent deposited in the spray chamber 7 is dried by a heater in the upper drying section and fixed on the surface.

[Effect of the invention] The projector sheet of the invention has the advantage that it can be written on with any writing implement such as water-based ink, pencil, and oil-based ink due to the fine irregularities on the surface formed by inorganic powder. be.

In addition, this surface covers the sticky surface of the plastic sheet, making it easier to handle like paper, and the antistatic treatment, which includes a thin layer of antistatic agent, prevents static electricity while maintaining writability. This prevents the film from adhering and also prevents dirt from attaching, making the sheet easy to handle and use.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the projector sheet of the present invention, FIG. 2 is a sectional view thereof, and FIG.
The figure is an explanatory view showing the process of applying an antistatic agent to the projector sheet of the present invention. The symbols in the figure are 1...Projector sheet, 2...Polypropylene sheet, 3...Inorganic powder dispersed resin layer, 4...Antistatic agent layer, 5...Antistatic agent coating chamber, 6...Projector sheet. Original sheet for Ector, 7...
...Antistatic agent spraying room, 8...Drying room.

Claims (1)

[Scope of utility model registration request] Both sides or one side of a laminate of a transparent or translucent plastic sheet 2 and a resin layer 3 containing a dispersed inorganic powder for surface roughening are exposed to an atmosphere of an antistatic agent suspended in the form of fine particles in a gas phase. A sheet for projectors that has been treated with antistatic treatment.