JP2778754B2 - Electromagnetic shielding gasket tape - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to an electromagnetic shielding gas installed between a main body opening of a shield case containing a communication device, a computer, and the like, and a lid for closing the opening. More particularly, the present invention relates to an electromagnetic shielding gasket tape comprising an embossed conductive metal foil and an adhesive layer laminated on the back surface of the metal foil.

(Prior Art) JP-B-47-51798 discloses a conductive adhesive tape which can be used also as an electromagnetic shielding gasket tape. The conductive adhesive tape includes a metal foil embossed so as to have a large number of small projections, a non-conductive adhesive layer laminated on the apexes of the small projections, and a release paper. When used as a gasket tape provided between the cover of the shield case and the opening of the main body, by being compressed,
The small protrusions break the insulation of the adhesive layer, so that conduction can also be obtained.

(Problem to be Solved by the Invention) In the above-mentioned conventional electromagnetic shielding gasket tape, contact between the end face of the lid or the main body and the metal foil of the electromagnetic shielding gasket tape is performed on the flat surface side of the embossing. Therefore, the contact is a surface contact. Thereby, the manufacturing accuracy of the end face of the opening of the main body of the shield case and the end face of the lid closing the opening, that is, if the flatness is poor, the pressure when the lid is closed does not concentrate, so that the metal foil and the conductive The adhesive layer cannot be sufficiently compressed. As a result, a long gap is formed between the electromagnetic shielding gasket tape and the end face of the lid or the opening of the main body, and there is a problem that a sufficient electromagnetic shielding ability cannot be obtained.

An object of the present invention is to provide an electromagnetic shielding gasket tape that exhibits high electromagnetic shielding ability without being affected by the manufacturing accuracy of the body of the shield case and the end face of the lid.

(Means for Solving the Problems) An electromagnetic shielding gasket tape according to the present invention is an electromagnetic shielding gasket tape comprising an embossed conductive metal foil and an adhesive layer laminated on the back surface of the conductive metal foil. On the surface of the conductive metal foil, a row of small ridges arranged two-dimensionally by embossing is formed, and the adhesive layer is formed in a recess on the back side of the row of small ridges. The conductive metal foil is adhered to a flat surface on the back surface of the conductive metal foil so as to form a gap therebetween, and the adhesive layer contains conductive particles dispersed therein.

More preferably, a release paper is provided on a surface of the adhesive layer opposite to the metal foil.

In the present invention, the rows of small ridges arranged two-dimensionally represent rows of small ridges intersecting with each other, and can also be expressed as a net-like formation.

(Effect) The electromagnetic shielding gasket tape according to the present invention is attached to the entire periphery of the opening of the main body of the shield case containing the communication device and the computer, and the opening is covered. The row of small projections formed by embossing the metal foil makes line contact with the end face of the lid, and pressure concentrates on the row of small projections in contact with the lid. As a result, the row of small projections in contact with the lid and the adhesive layer thereunder are easily elastically deformed in the thickness direction of the electromagnetic shielding gasket tape. As a result, all the small projection rows contact the end face of the lid, and the gap formed between the electromagnetic shielding gasket tape and the lid becomes a short gap corresponding to the length between the small projection rows, and the electromagnetic shielding ability is improved. .

Furthermore, since the adhesive layer contains conductive particles dispersed therein, conduction between the end face of the opening of the shield case body to which the electromagnetic shielding gasket tape is adhered and the metal foil is secured, and a reliable and stable electromagnetic The shielding performance can be exhibited.

(Example) An electromagnetic shielding gasket tape according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the electromagnetic shielding gasket tape according to the present invention. The electromagnetic shielding gasket tape 1
A flexible metal foil 2 embossed into a shape in which small rows of ridges are two-dimensionally arranged as viewed from the front side, and a flat surface 8 of the embossed metal foil 2 adhered to the metal foil 2. A conductive adhesive layer 3 in which conductive particles such as copper particles are dispersed,
A release paper 4 is adhered to the surface of the conductive adhesive layer 3 opposite to the metal foil 2.

When using, attach the electromagnetic shielding gasket tape 1 to the second
As shown in the figure, punching is performed according to the shape of the opening of the shield case main body 5. Next, the release paper 4 is peeled off and attached to the opening of the shield case main body 5. The cover 6 of the shield case is fixed to the shield case main body 5 with an appropriate fixing tool so as to sandwich the electromagnetic shielding gasket tape 1. At this time, as shown in FIG. 3, the lid 6 and the electromagnetic shielding gasket tape 1 come into contact with each other at the small projection rows 7 of the electromagnetic shielding gasket tape 1. Since this contact is a line contact, the pressure is concentrated on the small protrusion 7 and the conductive adhesive layer 3 thereunder, and these are sufficiently elastically deformed. Thereby, even if the flatness of the end face of the opening of the shield case main body 5 is poor, the small projection row 7 in contact with the lid 6 and the conductive adhesive layer 3 thereunder are sufficiently in the thickness direction of the electromagnetic shielding gasket tape 1. Since it is compressed, all the small projection rows 7 of the electromagnetic shielding gasket tape 1 come into contact with the lid 6. As a result, the gap 9 formed between the electromagnetic shielding gasket tape 1 and the lid 6 has a short length corresponding to the length between the small projection rows 7. That is, formation of a long gap that affects electromagnetic shielding is prevented, and high electromagnetic shielding performance is obtained.

FIG. 4 shows an embossed copper foil having a length between the small projection rows 7 of 0.7 mm and a thickness of 35 μm.
The electromagnetic shielding performance of the electromagnetic shielding gasket tape according to the present invention having a thickness of 145 μm excluding the above and the electromagnetic shielding gasket tape according to the prior art described above were compared and measured by the KEC method (Kansai Electronics Industry Promotion Center method). The results are shown. From these results, it can be seen that the electromagnetic shielding gasket tape according to the present invention has excellent electromagnetic shielding performance at 10 to 1000 MHz.

(Effects of the Invention) According to the present invention, there is provided an electromagnetic shield having a high electromagnetic shielding ability that is not affected by the manufacturing accuracy of the end faces of the main body and the lid of the shield case and that ensures the conduction between the shield case main body and the metal foil. A shielding gasket table is provided. In addition, since the components are equivalent to the electromagnetic shielding gasket tape of the prior art, the cost does not increase.

[Brief description of the drawings]

FIG. 1 is a perspective view of an embodiment of an electromagnetic shielding gasket tape according to the present invention, FIG. 2 is an exploded perspective view of a shield case showing a use state of the electromagnetic shielding gasket tape according to the present invention, and FIG. FIG. 4 is a cross-sectional view of a main part of a shield case using an electromagnetic shielding gasket tape according to the present invention, and FIG. 4 is a graph showing measurement results obtained by measuring the electromagnetic shielding ability of one embodiment of the electromagnetic shielding gasket tape according to the present invention by the KEC method. DESCRIPTION OF SYMBOLS 1 ... Electromagnetic shielding gasket tape, 2 ... Metal foil, 3 ... Conductive adhesive layer, 4 ... Release paper, 5 ... Shield case body, 6 ... Shield case lid, 7 ... Small projection Row, 8 ... flat surface.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H05K 9/00

Claims (2)

(57) [Claims] 1. An electromagnetic shielding gasket tape comprising an embossed conductive metal foil and an adhesive layer laminated on a back surface of the conductive metal foil, wherein the surface of the conductive metal foil is two-dimensionally embossed. An array of ridges is arranged on the back of the conductive metal foil so as to form a gap between the adhesive layer and the recess on the back side of the ridge. An electromagnetic shielding gasket tape, which is adhered to a flat surface, wherein the adhesive layer contains conductive particles dispersed therein. 2. The electromagnetic shielding gasket tape according to claim 1, wherein a release paper is provided on a surface of the adhesive layer opposite to the metal foil.