JPH08190812A - Flat shielding circuit body and its manufacture - Google Patents

Abstract

PURPOSE: To provide a manufacture of a flat shielding circuit body and by which the flat shielding circuit body is easily manufactured. CONSTITUTION: In one half portion of the conductive layer of a base film 1 plural circuits 14 to 16 are formed by etching, while in the other half a circuit plate 21 is formed leaving a shielding conductive layer 17. A conductive adhesive 19 is applied to an outside earth circuit 15, while an insulating adhesive 20 is applied to the other circuits, and the circuit plate 21 is folded back in the center. The shielding conductive layer 17 is connected to the earth circuit 15, and is bonded with the other circuits via the insulating adhesive.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat shield circuit body for simultaneously electrically shielding and grounding a circuit by folding back a circuit board on which a circuit and a conductive layer for shielding are formed by etching a conductive layer of a base film. The present invention relates to a manufacturing method thereof.

[0002]

2. Description of the Related Art FIG. 10 shows a conventional flat shield circuit body disclosed in Japanese Utility Model Laid-Open No. 6-2516. The flat shield circuit body 31 includes a conductive shield layer 35 such as a metal tape on the outer circumference of a flat cable 34 having a plurality of conductors 33 in parallel between flat insulating coatings 32.
And a ground wire 36 is connected to the conductive shield layer 35. The end portions of the conductor 33 project from both ends of the flat cable 34 to form a connection portion for the counterpart circuit body. The conductive shield layer 35 shields electric noise from the outside to the flat cable 34.

[0003]

However, in the above-mentioned conventional structure, a metal tape or the like as the conductive shield layer 35 is wound around the outer periphery of the flat cable 34,
Further, since the ground wire 36 is connected to the conductive shield layer 35, it takes a lot of time and labor for manufacturing, which deteriorates productivity and increases the cost of the product.

In view of the above points, the present invention provides a flat circuit body in which a conductive shield layer and a ground wire can be easily provided, and productivity can be improved and cost can be reduced, and a manufacturing method thereof. The purpose is to

[0005]

In order to achieve the above-mentioned object, the present invention attaches an etching resist to a conductive layer formed on a base film to form a predetermined circuit portion in one half of the conductive layer. Then, the conductive layer is etched to form a plurality of circuits in the circuit planned portion, and the shield conductive layer is left in the other half of the conductive layer to form a circuit board. Conductive adhesive is applied to the ground circuit on the outer side of the above, insulating adhesive is applied to other circuits, the circuit board is folded back from the center, and the conductive layer for shielding is adhesively connected to the earth circuit. And a method of manufacturing a flat shield circuit body in which another circuit is adhered via an insulating adhesive, and a base film folded back from the center, and a plurality of films formed on one half of the surface of the base film. Circuit of A shield conductive layer formed on the other half of the surface and facing the plurality of circuits, a conductive adhesive applied to an outer ground circuit of the plurality of circuits, and the ground circuit. Except for the insulating adhesive applied to the other circuit, the shield conductive layer is connected to the ground circuit with the conductive adhesive, and is adhered to the other circuit via the insulating adhesive. Adopt the flat shield circuit body.

[0006]

By folding back the circuit board at the center, the conductive layer for shielding is connected to the ground circuit with a conductive adhesive and is adhered to another circuit via the insulating adhesive. As a result, the plurality of circuits are covered with the conductive layer for shielding and electrically shielded. The outer ground circuit closes the shield circuit body and shields it auxiliary.

[0007]

1 to 9 show one embodiment of a method for manufacturing a flat circuit body according to the present invention. In this method, first, as shown in FIG. 1, a copper foil 2 as a conductive layer is adhered onto the surface of a flexible base film 1 made of synthetic resin to form a film 3 with a copper foil. Then, as shown in FIG.
A plating resist 5 is printed and applied on the surface of the copper foil 2 except for the power circuit formation planned portion 4.

The power circuit formation scheduled portion 4 is set within the range of the left half portion 6 of the copper foil 2. As shown in FIG. 3, the power circuit formation-scheduled portion 4 is subjected to high-speed electrolytic Cu plating, and a thick layer of the polymer layer 7 is plated on the copper foil 2 in the groove 8 of the plating resist 5.

Then, as shown in FIG. 4, the plating resist 5 is removed to expose the copper foil layer 2 and the polymerized layer 7. Further, as shown in FIG. 5, an etching resist 12 is formed on the polymerized layer 7 in the left half portion 6 of the copper foil layer 2, the thin film signal circuit and ground circuit formation planned portions 9 and 10, and the right half portion 11 of the copper foil layer 2. Apply by printing. The right half 11 of the copper foil layer 2 acts as a shield layer.

Then, the copper foil portion 13 without the etching resist 12 is removed by etching, and a thick film power circuit 14 is formed in the left half portion 6 on the base film 1 as shown in FIG.
Then, a thin-film ground circuit 15 and a signal circuit 16 are formed, and the electromagnetic shield copper foil layer 17 is left in the right half portion 11. The etching resist 12 is removed. In addition,
The method of forming the circuits 14 and 16 is described in Japanese Patent Application No. 5-115.
No. 747 has already been proposed.

Then, in FIG. 7, the copper foil layer 17 for shielding is used.
Front and rear end portions 18 in the circuit longitudinal direction between the base film 1 and the base film 1,
18 is integrally trimmed and removed with a constant width. Further, as shown in FIG. 8, a conductive adhesive 19 is applied on the surface of the outermost earth circuit 15, and another power circuit 14 and signal circuit 16 are provided.
The insulating adhesive 20 is applied by printing.

Finally, the right half portion 11 of the circuit board 21 having the shielding copper foil layer 17 is folded back from the center of the base film 1 (the portion indicated by the chain line a in the figure) toward the respective circuits 14 to 16.
The shielding copper foil layer 17 is replaced with an insulating layer (insulating adhesive) 20.
The power circuit 14 and the signal circuit 16 are adhered to the grounding circuit 15 by means of a conductive adhesive 19 and the side ends of the copper foil layer 17 for shielding are bonded and connected to the ground circuit 15 with a conductive adhesive 19.

As a result, the flat shield circuit body 22 as shown in FIG. 9 is completed. The terminals of the circuits 14 to 16 are exposed to the outside by the trimming to form the terminal portions 14a to 16a. The shielding copper foil layer 17 is adhesively connected to the ground circuit 15 with a conductive adhesive 19, and the insulating adhesive 2
It is deposited on the power circuit 14 and the signal circuit 16 through 0. The power circuit 14 and the signal circuit 16 are covered with the copper foil layer 17 for shielding and electrically shielded, and electric noise is released to the outside through the terminal portion 15a of the earth circuit 15.

[0014]

As described above, according to the present invention, the formation of the conductive layer for shield and the formation of the ground circuit are simultaneously performed, and the circuit board is folded back so that the ground circuit and the conductive layer for the shield are formed. Since the connection and the electrical shielding of other circuits by the conductive layer for shielding are performed at the same time, the flat shield circuit body can be easily manufactured with a small number of steps, and the manufacturing can be automated, thereby improving the productivity. Better, cost is reduced.

[Brief description of drawings]

FIG. 1 is a side view showing a film with a copper foil as one step of a method for manufacturing a flat shield circuit body according to the present invention.

FIG. 2 is a side view showing a state in which a plating resist is printed on a film with copper foil.

FIG. 3 is a side view showing a state in which a polymer layer is plated on a predetermined portion of the circuit.

FIG. 4 is a side view showing a state where the plating resist is removed.

FIG. 5 is a side view showing a state in which an etching resist is printed on a planned circuit portion and a conductive layer for shielding.

FIG. 6 is a side view showing a state where each circuit is formed by etching.

FIG. 7 is a perspective view showing a state in which an end portion of the circuit board on the side of the conductive layer for shielding is trimmed.

FIG. 8 is a perspective view showing a state in which a conductive and insulating adhesive is applied to the circuit.

FIG. 9 is a perspective view of a state where the circuit board is folded back from the center to form a flat shield circuit body.

FIG. 10 is a plan view showing a conventional example.

[Explanation of symbols]

 1 Base Film 2 Copper Foil 4, 9, 10 Planned Circuit Area 12 Etching Resist 15 Earth Circuit 17 Copper Foil Layer for Shield 19 Conductive Adhesive 20 Insulating Adhesive 21 Circuit Board 22 Flat Shield Circuit Body

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H05K 9/00 R

Claims (2)

[Claims] 1. An etching resist is adhered to a conductive layer formed on a base film to form a predetermined circuit portion in one half of the conductive layer, and the conductive layer is etched to form a plurality of portions in the predetermined circuit portion. A circuit is formed and a shield conductive layer is left in the other half of the conductive layer to form a circuit board, and a conductive adhesive is applied to an outer ground circuit of the plurality of circuits, An insulating adhesive is applied to another circuit, the circuit board is folded back from the center so that the shield conductive layer is adhesively connected to the ground circuit, and the other circuit is attached via the insulating adhesive. A method for manufacturing a flat shield circuit body, comprising: 2. A base film folded back from the center, a plurality of circuits formed on one half of the surface of the base film, and a plurality of circuits formed on the other half of the surface, facing the plurality of circuits. A conductive layer for shielding, a conductive adhesive applied to an outer earth circuit of the plurality of circuits, and an insulating adhesive applied to other circuits except the earth circuit, A flat shield circuit body characterized in that a conductive layer for shielding is connected to the earth circuit with a conductive adhesive and is adhered to another circuit via the insulating adhesive.