JPH08274417A - Flexible wiring board and its manufacture - Google Patents

Abstract

PURPOSE: To provide a flexible wiring board wherein peeling resistance of bent part used for a position wherein a wiring interval varies is improved and a highly efficient and inexpensive manufacturing method thereof which restrains an increase in the number of operation processes which increases in accordance with the increase in bending formation and bending positions. CONSTITUTION: This flexible wiring board has a long size film base 1, a conductor pattern 2 formed on the film base 1 and an insulation resin layer 3 consisting of a thermoplastic resin layer or a thermosetting resin layer formed to cover the conductor pattern 2 and is provided with a zigzag bending part whereto a flexible wiring board is bonded after heated and pressurized. When bonded by heating and pressurizing, it is prepared by bringing a heat resistant high polymer resin material into contact with it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible wiring board used for wiring in a place where wiring spacing varies due to mechanical operation inside various electronic devices, and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, flexible wiring boards have been widely used in order to reduce the size and weight of equipment and increase the density thereof. In such a situation, a long flexible wiring board is formed into a zigzag shape at locations where the wiring spacing fluctuates due to the mechanical operation inside the electronic device, and the inner surface of the bent portion is adhesively formed with double-sided tape to secure the wiring spacing. It is configured to play a damper-like role in response to fluctuations in the.

A conventional flexible wiring board will be described below with reference to FIGS. 4 and 5. As shown in FIG. 4, the conventional flexible wiring board has a long film base 11
A conductor pattern 12 formed on the upper side and a thermoplastic or thermosetting resin layer 13 formed so as to cover the conductor pattern 12, and a double-sided tape 14 is attached to a bending adhesive portion of a long flexible wiring board. It is configured so that the bent shape can be maintained after attachment and bending adhesion, and reinforcing plates 15 are formed on the lower surfaces of both ends of the film base 11.

In FIG. 5, a double-sided tape adhesive portion 16 is formed on the bent portion of the flexible wiring board.

[0005]

In the conventional flexible wiring board described above, when the variation interval is short, the double-sided tape 14 formed on the bent portion of the flexible wiring board has a pulling tape. Although the peeling force does not act, when the fluctuation interval is long, the peeling force acts strongly on the double-sided tape 14 formed on the bent portion of the flexible wiring board. If such a state is maintained for a long time, the double-sided tape adhesive portion 16 of the bent portion is peeled off and the initial shape cannot be maintained. Furthermore, if the number of folding points is increased, the number of places where the double-sided tape 14 is attached naturally increases, and there is a problem that the number of work steps such as attachment, peeling of release paper from the double-sided tape 14 and adhesion of the double-sided tape 14 increases.

The present invention solves such a conventional problem, improves the peeling resistance of the bent portion, and suppresses the increase in the number of working steps corresponding to the increase in the number of bent portions (many places), and is inexpensive. An object of the present invention is to provide a high-performance flexible wiring board and a manufacturing method thereof.

[0007]

In order to solve the above-mentioned problems, a flexible wiring board of the present invention covers a long film base, a conductor pattern formed on the film base, and the conductor pattern. A flexible wiring board comprising a bondable insulating material formed on the film base and the adhesive insulating material formed on the opposite surface of the conductor pattern on the film base, wherein the flexible wiring board is heated, It is provided with a zigzag bent portion that is pressed and bonded.

[0008]

In the flexible wiring board of this structure, when the wiring interval is long with respect to the variation of the wiring interval, even if the peeling force acts on the bent portion of the flexible wiring board for a long time, the bent portion is heated and pressed. Since they are adhered, the initial shape can be maintained without peeling off the bent adhesion part. further,
When it is necessary to provide a lot of zigzag parts when the wiring spacing fluctuates greatly, conventionally, a double-sided tape was attached to each zigzag part, each release paper was peeled off, and each part was bent and bonded. In this configuration, which had to be performed, since each of the folded portions can be bent and bonded together by heating and pressing, the increase in the number of working steps can be suppressed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A flexible wiring board and a method of manufacturing the same according to one embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the flexible wiring board of this embodiment includes a long film base 1 and this film base 1
The conductor pattern 2 formed on the conductor pattern 2 and the conductor pattern 2
An insulating resin layer 3 formed of a thermoplastic resin layer or a thermosetting resin layer so as to cover the insulating resin layer, and an insulating resin layer of a thermoplastic resin layer or a thermosetting resin layer on the film base 1 at least on the back surface of the bent portion. The layer 3 is provided, and the reinforcing plates 4 are provided on the lower surfaces of both ends of the film base 1.

The long flexible wiring board constructed as described above is folded into a zigzag shape as shown in FIG.
The bent portion (heating and pressure adhering portion) 5 is heated and pressed to adhere. At the time of heating and pressure bonding, a heat-resistant polymer resin material such as silicon rubber having a convex heating / pressing shape portion is brought into contact with the heating side and heated and pressed to bond.

According to the present embodiment, the bent portion 5 is adhered by heating and pressing even if the peeling force is strongly exerted when the fluctuation interval is long and the fluctuation interval is long. Therefore, as compared with the conventional folded and adhered portion adhered with the double-sided tape, the force for peeling is obtained stronger, and the initial state of the folded portion can be maintained for a long time.

FIG. 3 shows the operating state of this embodiment. In FIG. 3, a connector 7 provided at one end of a flexible wiring board having a bent adhesive portion 6 is connected to a printed circuit board 8 at a fixed portion, and a connector 9 provided at the other end thereof is connected to a printed circuit board 10 at a moving portion. Has been done. FIG.
In the case where the wiring interval variation interval shown in (a) is short, almost no peeling force is applied to the bending adhesive section 6, but the printed circuit board 10 of the moving section moves and the wiring interval variation interval is long. In the case of ', a large peeling force is applied to the bent adhesive portion 6. If the wiring is left a'for a long time in a state of being a'for a long time, the folded and bonded portion with a conventional adhesive such as a double-sided tape will be peeled off, making it difficult to maintain the initial state.

In this embodiment, the heating / pressurizing adhesive portion 5 shown in FIG.
Since pressure is applied, uniform heat and pressure are applied only to the bonded portion. As a result, heat and pressure are applied only to the necessary parts, and there is no change in the characteristics of other parts, and a flexible wiring board with high reliability can be constructed.

[0014]

As is apparent from the above description, according to the flexible wiring board and the method of manufacturing the same of the present invention, the flexible wiring board is long and flexible with respect to the wiring where the wiring interval varies due to the mechanical operation inside the electronic device. The wiring board is folded into a zigzag shape, and the bent portion is heated and pressure-bonded to improve the peeling resistance of the bent portion, and to suppress the increase in work man-hours corresponding to the increase in the number of bent portions (many places), it is inexpensive. It is possible to provide a high-performance flexible wiring board.

[Brief description of drawings]

FIG. 1A is a plan view of a flexible wiring board according to an embodiment of the present invention before bending, and FIG. 1B is a sectional view taken along line BB ′ of FIG. 1A.

FIG. 2 is a perspective view of the flexible wiring board after bending and bonding.

FIG. 3 (a) is a perspective view showing an operating state of the flexible wiring board when the variation interval of the same wiring interval a is short, and (b) shows an operating state of the flexible wiring board when the variation interval of the same wiring interval a ′ is long. Perspective view

FIG. 4A is a plan view of a conventional flexible wiring board before bending, and FIG. 4B is a sectional view taken along line AA ′ of FIG. 4A.

FIG. 5 is a perspective view of the flexible wiring board after bending and bonding.

[Explanation of symbols]

 1 Film base 2 Conductor pattern 3 Insulating resin layer 5 Bending part (heating and pressure bonding part)

Claims (3)

[Claims] 1. An insulating resin layer comprising a long film base, a conductor pattern formed on the film base, a thermoplastic resin layer formed so as to cover the conductor pattern, or a thermosetting resin layer. A flexible wiring board comprising: a flexible wiring board having a zigzag bent portion that is bonded by being heated and pressed. 2. An insulating resin layer made of a thermoplastic resin layer or a thermosetting resin layer is provided on at least the back surface of the bent portion of the film base, and the insulating resin layer is adhered by being heated and pressed during bending. The flexible wiring board according to claim 1, wherein the flexible wiring board is provided. 3. A set of flexible wiring boards covered with a thermoplastic resin layer having a conductor pattern formed on at least one side on the lower side or an insulating resin layer made of a thermosetting resin layer is folded in a zigzag shape. A method for manufacturing a flexible wiring board, in which the insulating resin layers are opposed to each other in order to bond the parts, and a convex polymer resin material having heat resistance is brought into contact with one of the bonded parts to heat and pressurize.