JPH0142158B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a see-through high frequency radio wave shielding plate used for the door of a high frequency heating device such as a microwave oven, and a method for manufacturing the same. The purpose is to provide a high frequency radio wave shielding plate whose interior is easy to see through, easy to manufacture, and suitable for mass production, and a method for manufacturing the same.

2. Description of the Related Art A shield plate is used on the door of a microwave oven or the like to shield high frequency radio waves and to allow the inside to be seen through. Conventionally, as such a shielding plate, a metal plate having a large number of through holes or a metal film layer laminated on a glass plate or between glass plates has been used. However, when the metal plate is provided, the through holes are generally formed by press working, which is cumbersome and unsuitable for forming fine through holes. In addition, when providing a metal film layer, a paste containing metal powder is applied to the glass plate by screen printing, or
This method has relied on a method of depositing aluminum or the like on the surface of a glass plate using a vacuum evaporation method. However, since the former method uses screen printing, it is not possible to create sufficiently fine holes, and furthermore, since the paste contains a resin binder, the conductivity of the metal film layer is relatively low. Furthermore, it takes time and effort to heat and bake the glass plate in order to fuse it to the surface of the glass plate.
In addition, in the latter method, it is time-consuming to perform vacuum deposition directly on the glass plate, and the deposited film has the disadvantage that it is difficult to adhere firmly, and the glass plate created has a half-mirror shape, which can be used inside microwave ovens, etc. It was difficult to see.

In view of the above-mentioned drawbacks, the inventors of the present invention sought to provide a high-frequency radio wave shielding plate that can be easily mass-produced and is provided with fine and precise through holes, and as a result of various considerations and researches, they completed the present invention. It has been reached. That is, in the present invention, a metal vapor deposited film layer 4 and an ink layer 5 having hiding properties are laminated on 8 surfaces of a transparent plate such as a glass plate,
This is a high frequency radio wave shielding plate characterized in that the two layers have dot-shaped through holes 7, and a method for manufacturing the same.

The present invention will be explained in more detail below based on the drawings.

In the present invention, a transfer material as shown in FIG. 1 is used. This transfer material is made by sequentially laminating a release layer 2, a resin layer 3, a metal vapor deposited film layer 4, an ink layer 5, and an adhesive layer 6 on a base sheet 1.
The ink layer 5 is provided with halftone dot-like through holes 7.

The transfer material is prepared as follows. First, a release layer 2 and a resin layer 3 are coated and formed on a base sheet 1 . For the base sheet 1 and the release layer 2, those used for transfer materials used in a normal so-called transfer printing method are used. The resin layer 3 is provided to increase the adhesion of the metal vapor deposited film layer 4, and is formed on the release layer 2 using, for example, polyvinyl, polyester, polyurethane, polyacrylic, or other cellulose resin. It is formed.

A metal vapor deposition film layer 4 is formed thereon using a metal such as aluminum, chromium, nickel, copper, etc. by vacuum vapor deposition, sputtering, ion plating, or the like. Furthermore, an ink layer 5 is provided. The mesh-like through holes in the metal vapor deposited film layer 4 and the ink layer 5 are formed as follows. That is, first, a metal vapor deposition film is provided on the entire surface of the resin layer 3, and an ink layer 5 having halftone dot-like through holes 7 is printed thereon. The ink layer 5 is made of alkyd-based, vinyl-based, acrylic-based, polyester-based, etc., which serves as a resist against alkali or acid, and uses an ink having hiding properties, and is printed by offset, gravure, or other printing means. After forming the ink layer 5,
When the sheet is washed with an alkaline solution such as sodium hydroxide or potassium hydroxide or an acidic solution such as hydrochloric acid or sulfuric acid, the metal vapor deposited film in the perforated areas is removed.
A dot-shaped through hole is formed. In addition, the through hole 7 to be formed
is 70 lines normally used in general printing plate making technology
The pitch is 200 lines, preferably 180 to 200 lines, and the size is appropriately selected depending on the required transmittance of the shielding plate, but an area occupation rate of about 20% to 40% is preferable. That is, in this case, it is preferable to form the ink layer 5 with a halftone dot density of 60% to 80% (see FIG. 2).

An adhesive layer 6 is applied and formed on the ink layer 5. The adhesive used for ordinary transfer materials is also used.

Transfer is performed on the transparent plate 8 using the transfer material configured as described above. As the transparent plate 8, a glass plate or a heat-resistant plastic plate is used. First, a transfer material is placed so that the adhesive layer 6 side is in contact with the surface of the transparent plate 8, heated and pressed as necessary, and then the base sheet 1 is peeled off, and the peeling layer 2, resin layer 3, metal vapor deposition film layer 4,
The ink layer 5 and the adhesive layer 6 are transferred onto the surface of the transparent plate 8.

The high frequency radio wave shielding plate according to the present invention obtained as described above can be used for the door of a microwave oven, etc., but when used, it must be installed so that the metal vapor deposited film layer 4 is located inside the ink layer 5. Then, when viewed from the outside, the metal vapor deposited film layer 4 is hidden by the presence of the ink layer 5 having a hiding property, and the mirror effect is prevented, so that the inside can be more easily seen.

In addition, if a relatively hard resin is used for the release layer 2, or if a glass plate is further placed on the release layer 2 and used like a laminated glass plate, the metal vapor deposited film layer 4 and other layers can be prevented from being scratched or peeled off due to contact. (See Figures 3 and 4) Since the present invention is a high-frequency radio wave shielding plate and a method for manufacturing the same as described above, it is possible to easily form fine dot-shaped through holes according to the present invention. A shielding plate can be obtained, and since the manufacturing method thereof uses a transfer printing method, it is suitable for mass production. Even when the obtained shielding plate is applied to the door of a microwave oven or the like, it is easy to see through the inside, and its light transmittance can be designed as necessary, and various other effects can be obtained.
Therefore, the high frequency radio wave shielding plate and its manufacturing method are expected to be widely used as shielding plates for high frequency heating devices such as microwave ovens where it is necessary to see inside the heating chamber.

[Brief explanation of drawings]

FIG. 1 is a partially enlarged sectional view of a transfer material used in the present invention, FIG. 2 is a partially enlarged plan view of an ink layer in the transfer material, and FIGS. 3 and 4 are high-frequency radio wave shielding according to the present invention. FIG. 3 shows partially enlarged cross-sectional views of embodiments of the plate, respectively. In the figure, 1...Base sheet, 2...Peeling layer, 3...
...Resin layer, 4...Metal deposited film layer, 5...Ink layer, 6...Adhesive layer, 7...Through hole, 8...Transparent plate.

Claims (1)

[Scope of Claims] 1. A high-frequency radio wave shielding plate, characterized in that a metal vapor-deposited film layer and a masking ink layer are laminated on a transparent plate surface, and the two layers have dot-shaped through holes. 2. A release layer, a resin layer, a metal vapor deposited film layer, an ink layer having concealing properties, and an adhesive layer were sequentially laminated on the base sheet, and halftone dot-like through holes were provided in the metal vapor deposited film layer and the ink layer. The adhesive layer side of the transfer material is placed on the transparent plate surface, the base sheet is peeled off, and the peeling layer,
A method for manufacturing a high frequency radio wave shielding plate, which comprises transferring a resin layer, a metal vapor deposition film layer, an ink layer and an adhesive layer onto a glass plate surface.