JPH06140790A - Electromagnetic wave shielding film for electronic component and its manufacture - Google Patents

Abstract

PURPOSE:To facilitate electromagnetic shielding of electromagnetic components on a substrate without causing short circuits with circuit patterns and the like. CONSTITUTION:A flexible insulating film 10 face is coated with a silver paste except in its periphery and cured to insulatively coat 12 its coated face 11. A tacky layer 13 is formed at a film 10 end and coated with a mold release paper 14. This electromagnetic shielding film P is made cylindrical to shield electromagnetic waves by wrapping an electronic component. This cylindrical form is retained by adhesion of both ends with the tacky layer 13, and the end 11a of the coated face 11 is soldered to ground patterns on the substrate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film which covers electronic parts of a substrate and shields electromagnetic waves from the film.

[0002]

2. Description of the Related Art As shown in FIG. 6, various electronic components 2 are provided on a printed wiring board 1, for example, to prevent malfunctions.
There is something that needs to shield electromagnetic waves from the outside or electromagnetic waves emitted by itself. In such a case, conventionally, the aluminum case 3 has been covered as shown in FIG. However, this aluminum case 3 is bulky and
Installation was troublesome, and improvement was desired.

For this reason, as shown in FIG. 7, a technique has been proposed in which the electromagnetic wave shielding film 4 covers the electronic component 1 to shield the electromagnetic wave.

However, this conventional general tape 4 is obtained by sticking a copper foil on the entire surface of a plastic film and cutting it into a plurality of pieces of a required size. That is,
Explaining with reference to FIG. 5, a copper foil is attached to the entire surface of the film Q, and it is divided into 15 equal parts. For this reason, the copper foil edge is also present on the edge of the tape 4 and is electrically conductive, and the flexibility of the film 4 causes the edge to unnecessarily touch other electronic components 2 and circuits. There is. If the edge touches the circuit unnecessarily, problems such as a short circuit will occur.

Further, a copper foil is attached to the entire surface of the plastic film, and the copper foil is etched to form a plurality of foil pieces.
That is, a piece indicated by reference numeral 11 in FIG. 5 is provided on the plastic film at a required interval,
There is also a tape 4 obtained by cutting the film portion of the piece with a separation distance of film exposure on the periphery. This tape 4 has no risk of shorting the edges.

However, the etching process is complicated, and the film 4 also needs corrosion resistance and is expensive.

An object of the present invention is to provide at low cost an electromagnetic wave shielding film that is free from the risk of edge short circuit.

[0008]

In order to solve the above-mentioned problems, in the present invention, a conductive coating material is applied and cured on the entire surface at a constant distance from the edge of the flexible insulating film, The coated surface is covered with insulation except the entire surface or a part of the edge. The coating shape is appropriately set in consideration of the shield area of the electronic component to be shielded.

In this structure, an adhesive layer may be formed on one surface of the end of the flexible insulating film, and the adhesive layer may be covered with release paper.

The electromagnetic wave shielding film having the above structure is
On the surface of the flexible insulating film, a conductive paint is used to print the above-mentioned coating shape at intervals in the vertical and horizontal directions and to cure, and after insulating coating on the upper surface, each coated surface of the conductive paint is surrounded by it. It can be obtained by cutting while leaving the portion not coated with the conductive paint.

The flexible insulating film includes a thermoplastic film, a thermosetting plastic film,
Not only a synthetic resin film such as an engineering plastic film, but any other insulating film such as paper may be used.

Various known pastes such as copper paste, silver paste, Ni paste, and carbon paste can be used as the conductive paint.

The above-mentioned insulating coating may be a laminate of the above-mentioned insulating film, hot pressing, sticking, etc., as well as thermosetting or UV.
It can be by curing resin coating. For the coating, known means such as printing and coating can be adopted.

[0014]

The electromagnetic wave shielding film thus constructed is attached in the same manner as a conventional metal film to shield the electromagnetic wave.
At this time, since there is no paint on the insulating film around the conductive paint, there is no risk of the paint layer unnecessarily touching other electronic components and circuits to cause a short circuit.

If there is an adhesive layer, both ends of the film are attached and attached with the adhesive layer. If not, known means such as staple (stapler) and adhesive is adopted.

[0016]

EXAMPLE As shown in FIGS. 1 and 2, width: 1.8 cm,
Length: 4.2cm polyimide film (thickness: 50μ
m) 10 is coated with a conductive paint 11 made of silver paste to a thickness of about 25 μm except on its periphery, and its coated surface 1
1 is coated (applied) with ultraviolet (UV) curable insulating resin 12
Has been done. A part 11 a of the coating surface 11 reaches the edge of the film 10, and the part 11 a is not covered with the insulating resin 12.

An adhesive layer 13 is formed on the edge of the film 10, and the adhesive layer 13 is covered with a release paper 14.

The size and shape of the coating surface 11 may be appropriately determined according to the electronic component 2 to be coated. As shown in FIG. 3, the surface is not solid coating but linear or mesh-like. But it's okay.

In this embodiment, as shown in FIG.
The upper electronic component 2 is covered so as to wrap it, both ends thereof are adhered with the adhesive layer 13, and a part 11a of the coated surface 11 is soldered to the shield layer 1a on the substrate 1 or the ground pattern.

FIG. 5 relates to the manufacturing method of the above embodiment, in which the coating surfaces 11 and 11a are formed on a film Q or a film roll having a required size by screen printing or intaglio printing at required intervals, Similarly, the UV resin 12 is coated on the surface 11 by screen printing or the like. The double-sided adhesive tape a is attached with one-sided release paper 14 in contact with the coating layer 12. From this one,
The electromagnetic wave shielding film P shown in FIG. 1 or 3 is punched with a Thomson blade. This manufacturing means enables integrated production from roll to roll.

The insulating coating 12 can also be formed by film lamination or hot pressing. Further, when the conductive paint 11 has poor solderability, a conductive paint having good solderability, for example, the copper paste shown in Japanese Patent Application No. 1-139572 of the applicant of the present invention is spot-coated on the coating surface 11a. It is good to hit or drop a conductive eyelet. This spot coating and eyeleting are performed before punching the shielding film P with the above-mentioned Thomson blade. When the coating surface 11a is not provided, an eyelet penetrating the insulating coating 12 is preferable.

[0022]

Since the present invention is constructed as described above, the electromagnetic wave shielding of electronic parts can be smoothly carried out without causing a problem such as a short circuit.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment.

FIG. 2 is a sectional view of the same embodiment.

FIG. 3 is a perspective view of another embodiment.

FIG. 4 is an explanatory diagram of the use of the embodiment.

FIG. 5 is an explanatory diagram for manufacturing the embodiment.

FIG. 6 is a perspective view of a conventional example.

FIG. 7 is a perspective view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed wiring board 2 Electronic component 10 Flexible insulating film 11 Conductive paint application surface 12 Insulation coating 13 Adhesive layer 14 Release paper P Electromagnetic wave shielding film a Double-sided adhesive tape

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroaki Shinohara 21 No. 21, Saiin-Azuka-cho, Saiin, Ukyo-ku, Kyoto-shi, Kyoto

Claims (4)

[Claims] 1. An electromagnetic wave shielding film for electronic parts, which is obtained by applying and curing a conductive paint on the entire surface of the flexible insulating film, which is separated from the edge by a certain distance, and insulating the applied surface. 2. The electromagnetic wave shielding film for an electronic component according to claim 1, wherein a part of the edge of the coated surface is exposed without insulating coating. 3. The electromagnetic wave shielding film for electronic parts according to claim 1, wherein an adhesive layer is formed on one surface of an end of the flexible insulating film, and the adhesive layer is covered with a release paper. 4. The surface of the flexible insulating film is printed with an electrically conductive coating so that the shape of the coating surface according to claim 1 is printed at a distance from each other in the vertical and horizontal directions, and is cured. Then, a method for producing an electromagnetic wave shielding film for electronic parts by cutting each coating surface of the conductive paint, leaving a portion around the conductive paint not coated with the conductive paint.