JPH0760958B2 - Electromagnetic shield casing - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a casing capable of housing electric / electronic components and equipment and shielding from electromagnetic waves.

[Conventional technology and its problems]

Conventionally, as a casing having an electromagnetic wave shielding property,
Applying paint mixed with conductive powder to the surface of synthetic resin, or applying metal plating or metal deposition to form a conductive coating on the surface, or kneading conductive filler such as metal powder or carbon fiber. There is something complicated.

Among the above, the method for forming a conductive coating requires a coating forming treatment one by one after molding the casing, resulting in poor workability and high cost, and the coating peels off during handling. There is an easy problem.

On the other hand, the latter has a problem that the physical properties of the synthetic resin are deteriorated by the filler and sufficient electromagnetic wave shielding properties cannot be obtained.

In addition to the above, there are also those using a metal plate or metal foil,
Although it has excellent electromagnetic wave shielding properties, it has a problem that it is difficult to process it into a complicated shape.

In addition, electrostatic charges on the surface of the casing may cause electrostatic breakdown of electronic components and the like, and a preventive measure for this is also required.

An object of the present invention is to solve the above problems, and in response to the above demands, to provide a casing made of a material which has an excellent antistatic effect, a good electromagnetic shielding property, and can be processed into a complicated shape. It is to be.

[Means for achieving the purpose]

In order to achieve the above object, in the present invention, at least one surface of the heat-shrinkable synthetic resin film, an aluminum foil is laminated via an intermittent adhesive layer, and a heat-shrinkable sheet is formed. The electromagnetic wave shield casing was formed.

In addition, a thermoplastic synthetic resin layer may be provided on the surface opposite to the one surface on which the aluminum foil is laminated of the above-mentioned sheet, and this may be molded. You may shape | mold what laminated | stacked with the film made to oppose and the thermoplastic synthetic resin layer was interposed.

[Action]

Since the aluminum foil is used as described above and the foil is exposed, it has an excellent electromagnetic wave shielding property and at the same time has an antistatic effect, and a large number of fine wrinkles are previously formed on the aluminum foil. Therefore, the wrinkles do not absorb the spread at the time of molding and the foil is not broken, and the foil can be molded into a complicated shape.

〔Example〕

First, an original sheet containing an aluminum foil will be described with reference to FIGS. 1 to 3.

As shown in FIG. 1, the original sheet 1 is obtained by laminating an aluminum foil 4 on a heat-shrinkable synthetic resin film 2 with an intermittent adhesive layer 3 interposed therebetween.

Further, as shown in FIG. 2, aluminum foil 4 may be laminated on both sides of the heat shrinkable film 2, or, as shown in FIG. 3, two sheets shown in FIG. 1 are superposed. It may be something like this.

The heat-shrinkable synthetic resin film 2 is made of resin such as polyethylene, polypropylene, vinyl chloride, polystyrene, polyester, ethylene-vinyl acetate copolymer,
It is preferable to use a material having a shrinkage ratio as large as possible, for example, about 50%. The film 2 may be a single body or a laminated body of two or more kinds of films.

The intermittent adhesive layer 3 is a film 2 and an aluminum foil 4.
It suffices to use a means capable of bonding together, and in addition to the adhesive agent, by utilizing the characteristics of the film 2, heat fusion or ultrasonic fusion may be used. The pattern of the adhesive layer 3 may be any of the linear shape as shown in FIG. 4 (a), the dot shape as shown in (b), and the lattice shape as shown in (c). Any pattern may be used as long as it has the intermittent portion 5 without being provided in the. A resin layer that flows by heating may be present in the intermittent portion 5.

In addition, a printing or coloring layer can be provided on the surface of the aluminum foil 4 if necessary. Further, a plurality of aluminum foils 4 may be attached and used.

When the original sheet 1 as described above is heated, it is possible to obtain the results shown in FIGS.
As shown in the figure, while the film 2 shrinks, the aluminum foil 4 is bonded to the film 2 via the intermittent bonding layer 3, so that as the film 2 shrinks, the respective intermittent portions 5 , Wrinkles are generated,
The forming sheet 10 is formed.

As shown in FIG. 5, a thermoplastic synthetic resin layer 6 may be provided on the surface of such a sheet 10 opposite to the aluminum foil 4. Of course, the resin layer 6 can be provided on the sheet 10 shown in FIGS. 6 and 7.

For laminating the film 2 and the resin layer 6, an adhesive may be used in addition to extrusion, thermocompression bonding and the like.

When the adhesive is used, for example, if the film 2 is a vinyl-based adhesive, a vinyl-based or urethane-based adhesive, the film 2 is used.
If is a polypropylene-based adhesive, it is preferable to use a polyurethane-based adhesive, for example. In both cases, it is preferable to use an adhesive that strengthens the adhesion between both and retains a certain degree of thermoplasticity.

As shown in FIG. 8, two sheets of FIG. 5 may be laminated with a thermoplastic synthetic resin layer 6 so that the films 2 face each other to form a molding sheet.

Such a sheet 10 is molded to form a casing as shown in FIG. 9, for example. In the figure, A is an electronic component, 20
Is the substrate. The aluminum foil 4 may appear on either the outer surface or the inner surface of the casing depending on the mounting portion of the ground terminal, and the sheet 10 of FIGS.
By molding, the aluminum foil is exposed on both the inner and outer surfaces.

The shape of the casing is arbitrary. Round, oval,
Any shape such as a polygon may be used.

〔effect〕

According to the present invention, as described above, the heat-shrinkable film is attached to the aluminum foil, the heat-shrinkable film is heat-shrinked, and the casing is formed by the sheet in which the fine wrinkles are formed on the aluminum foil. Even when rolled, the wrinkles of the aluminum foil absorb the elongation and breakage does not occur,
It can be formed into a complicated shape, and the excellent electromagnetic wave shielding property of aluminum foil is maintained as it is. Also, since the aluminum foil appears on the surface, it is possible to prevent electrostatic charge and protect stored items from electrostatic damage. The effect such as being able to be protected can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to FIG. 3 are sectional views showing some examples of original sheets used for forming sheets, FIG. 4 is a plan view showing a pattern of an adhesive layer, and FIG. 5 to FIG. FIG. 7 is a cross-sectional view showing a molding sheet obtained by heating and shrinking the above-mentioned original sheet, FIG. 8 is a cross-sectional view showing another example of the molding sheet, and FIG. 9 is a cross-sectional view of a casing. 1 ... Original sheet, 2 ... Heat-shrinkable synthetic resin film, 3
...... Intermittent adhesive layer, 4 ...... Aluminum foil, 5 …… Intermittent part, 8 …… Thermoplastic synthetic resin layer, 10 …… Molding sheet,
20 ... substrate.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Mamoru Kamata 1-25 Toyo Aluminum Co., Ltd. 4-25, Minamikyutaro-cho, Higashi-ku, Osaka-shi, Osaka

Claims (3)

[Claims] 1. An electromagnetic wave shield casing in which an aluminum foil is laminated on at least one surface of a heat-shrinkable synthetic resin film via an intermittent adhesive layer and a heat-shrinkable sheet is formed. 2. An aluminum foil is laminated on at least one surface of a heat-shrinkable synthetic resin film via an intermittent adhesive layer, and the sheet heat-shrinked is laminated on the surface opposite to the one surface of the aluminum foil. An electromagnetic wave shield casing formed by molding a thermoplastic synthetic resin layer. 3. An aluminum foil is laminated on one surface of a heat-shrinkable synthetic resin film via an intermittent adhesive layer, and two sheets are heat-shrinked, and the heat-shrinkable synthetic resin film faces each other. Then, an electromagnetic wave shielding casing is formed by laminating the thermoplastic synthetic resin layers and then molding the layers.