JP3309780B2 - Flexible wiring and intermediate film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible wiring body, and more particularly to a flexible wiring body used for internal wiring of OA equipment, home electric appliances, automobiles and the like.

[0002]

2. Description of the Related Art In general, a flexible wiring body is a general term for a flexible flat cable and a flexible printed circuit. After forming a substantially linear conductor on a base film, a conductor pattern is formed. It is formed by bonding a coverlay film on this conductor pattern.

[0003] The above-mentioned conductor pattern constitutes a conductive intersection where a certain conductor intersects with another conductor in an electrically connected state or an insulated intersection where the certain conductor intersects in an electrically insulated state. Things are common.

[0004]

In order to form the above-mentioned conductive intersection and insulated intersection, the present applicant has
In Japanese Patent Application No. 9-66723, which has been previously proposed, an intermediate film is interposed between one conductive wire and another conductive wire constituting a conductive intersection and an insulating intersection, and the intermediate film faces the conductive intersection. An opening is provided to ensure electrical continuity between one conductor and the other conductor at the conductive intersection, and to intersect between the one conductor and the other conductor at the insulating intersection. Which is designed to insulate the semiconductor device.

[0005] When such an intermediate film is employed, the conductive intersection and the insulating intersection can be configured in more various arrangements, and furthermore, solder or conductive adhesive is provided in the opening formed in the intermediate film. By filling the conductive connecting means such as the above, it is also possible to ensure the continuity of the two conductors. However, when the intermediate film as described above is employed, when the flexible wiring body is bent, the conductive wire portion constituting the conductive intersection and the opening of the intermediate film are filled to reinforce the contact pressure at the conductive intersection. There is a problem that a large stress easily acts on the conductive connecting means. This is because the provision of the opening tends to cause stress concentration around the opening, which has a disadvantage that the connection state is adversely affected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to provide a flexible wiring body and an intermediate film with high reliability, in which resistance of a conductive intersection portion to an external force is enhanced.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a conductive crossing portion which crosses in an electrically connected state, and an insulated crossing portion which crosses in an electrically insulated state. And a pair of insulating films for laminating the conductors, interposed between one of the conductors and the other conductor constituting the conductive intersection and the insulating intersection, and opening the conductive intersection. A band-shaped intermediate film having an opening and interposed at an insulating intersection portion to maintain an insulated state, wherein the intermediate film has a notch portion in a longitudinal direction that avoids concentration of stress on a portion defining the opening. It is a flexible wiring body characterized by being formed at intervals.

In the invention including the specific matter, when the flexible wiring body in which the conductive intersection and the insulation intersection of the conductor are formed by the intermediate film is bent, the stress caused by the bending is concentrated on the notch and the opening is partitioned. And therefore, it is less likely to act on the conductive intersection. Here, the “notch portion” is a general term for a portion where the shape is suddenly changed locally, and it does not matter whether the shape is a linear shape or a curved shape.
This "notch" is mainly formed at a portion facing the insulating intersection. This is because, even if the stress is concentrated on such a portion, the insulating ability does not deteriorate, so that the electrical connection state is not affected at all.

Another aspect of the present invention is that a conductive crossing portion that intersects in an electrically connected state is interposed between one conductive wire and another conductive wire that constitutes an element of a flexible wiring body,
A belt-shaped intermediate film having an opening for opening the conductive intersection, wherein cutouts are formed at intervals in the longitudinal direction to avoid concentration of stress on a portion defining the opening. An intermediate film characterized in that:

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
A preferred embodiment of the present invention will be described in detail. FIG. 1 is a process diagram showing a manufacturing process of a flexible wiring body according to one embodiment of the present invention.

As shown in FIG. 1, a flexible wiring body F according to the embodiment shown in the drawing has, in a final form, a conductive intersection portion PT to which electrically conductive wires P1 and P2 are connected, and an electrically insulated insulating portion. And an intersection PD.
When manufacturing this flexible wiring body F, first, in step (A), a material film 1 serving as a base film is placed on a well-known XY plotter (not shown), and a conductor P1 is laid out. Is formed. The base film 1 has an adhesive 1A applied to its upper surface,
The wired conductor P1 is adhered to the material film 1 by the adhesive 1A, and a part of the conductor pattern P is formed on the base film 1.

Next, in the step (B), the intermediate film 5 is attached. This intermediate film 5 has an opening 5A facing a part of the conductive wire P1 forming the conductive pattern P in the step (A), and this opening 5A forms another conductive intersection portion PT as described later. The electrical connection between the conductor P2 and the conductor P1 is allowed. Further, in the step (C), another conductive wire P2 forming the intersections PT and PD is laid on the intermediate film 5, and the intermediate film 5 is formed.
Is filled with conductive connection means 6 (see FIG. 2). Here, the conductive connecting means 6 is preferably soldered, and then a conductive adhesive is suitable. By this step (C), the conductive crossing part PT is formed on the opening 5A, while the insulating crossing part PD is formed where the intermediate film 5 is solidly interposed between the conductive wires P1 and P2. Will be.

Next, in step (D), the cover film 3 is bonded to the base film 1 and
(See step (E)). When the laminate L is formed, a cutter is attached to the XY plotter in step (E), and a predetermined final form product PF is formed from the laminate L. This final form product PF is intended to be “final” in processing with an XY plotter, and does not necessarily mean that it is a final product. In other words,
The final form product PF may be an intermediate product of the final product. Therefore, the final product PF may be further cut in a later step to produce a final product.

[0014] Of the above-described steps (A) to (E), the intermediate film 5 to be adhered in the step (C) has the opening 5A.
Thereby opening the conduction intersection PF, and the one conducting wire P1
And the other conductive wire P2 are electrically connected, and the contact pressure between them is ensured by the conductive connecting means 6 filled in the opening 5A. What is particularly notable in the illustrated embodiment is that a cutout portion 5B is formed in the intermediate film 5.

FIG. 2 is an enlarged schematic front view showing a main part of the intermediate film 5 according to the embodiment of FIG. Referring to the figure, the intermediate film 5 is formed in a band shape as a whole, and a constricted portion 5D in which an annular portion 5C centering on a portion where the opening 5A is formed is narrowed by a notch 5B.
Are formed in a continuous shape. The width in the diameter direction (= outer diameter D−inner diameter d) of the annular portion 5C is set to be larger than the width L of the constricted portion 5D, whereby an external force acting in the direction in which the intermediate film 5 bends. When receiving the stress, the stress concentrates on the constricted portion 5D,
It does not easily act on the annular portion 5C, that is, the opening 5A where the conduction intersection PF is formed.

FIG. 3 is a schematic sectional view showing a state where the flexible wiring body F according to the embodiment of FIG. 1 is bent. As shown in the figure, in the configuration described above, the notch 5B is provided in the intermediate film 5 to form the constricted portion 5D where the stress is concentrated, so that when the flexible wiring body F is bent, the constricted portion 5D is formed. The portion 5D is bent as a node, and the conduction intersection P
The part where F is formed shows a behavior that it is difficult to bend. As a result, the conducting wire P1,
Since the force for separating P2 is less likely to act, the two conductors P
1, the connection state of P2 is maintained for a long period of time, so that there is a remarkable effect that the reliability of the flexible wiring body F can be improved.

The above embodiment is merely an example of a preferred specific example of the present invention, and the present invention is not limited to the above embodiment. FIG. 4 is a schematic front view showing an intermediate film applicable to the present invention. FIG. 4A is FIG.
It is an intermediate film 5 adopted in the embodiment. In the intermediate film 5, an annular portion 5C and a constricted portion 5D are defined by a curved notch 5B.

Similarly, as shown in FIG. 4B, an intermediate film 15 in which the opening 5A is covered in a rectangular shape by the linear cutout 5B may be employed. Further, as shown in FIG. 4C, an intermediate film 25 in which the opening 5A itself is formed in a rectangular shape may be employed. 5 and 6 show still another intermediate film applicable to the present invention,
(A) is a schematic front view, and (B) is a schematic side view.

The intermediate films 35, 45 shown in these figures
As shown in FIGS. 5A and 5B, the “notch portion” 5B is a general term for a portion where the shape is suddenly changed, and the thickness T of the intermediate films 35 and 45 is one as shown in FIGS. The notch 5B may be formed by suddenly changing the portion and setting it to be thin, and the stress may be concentrated on this portion. In addition, as a configuration in which the thickness T is partially changed suddenly as shown in FIG.
As shown in FIG. 6 (B), besides being integrally formed by rolling or cutting, etc., as shown in FIGS. 6 (A) and 6 (B), two layers of films 45E and 45F are laminated and integrated. May be.

It goes without saying that various design changes are possible within the scope of the claims of the present invention.

[0021]

As described above, according to the present invention,
By providing the notch in the intermediate film, even when an external force acts on the flexible wiring body, the stress caused by the external force does not concentrate on the conductive intersection, so that the resistance due to the external force increases, and the reliability of the conductive part increases. Effect.

[Brief description of the drawings]

FIG. 1 is a process diagram showing a manufacturing process of a flexible wiring body according to an embodiment of the present invention.

FIG. 2 is an enlarged schematic front view showing a main part of an intermediate film according to the embodiment of FIG. 1;

FIG. 3 is a schematic sectional view showing a state where the flexible wiring body according to the embodiment of FIG. 1 is bent.

FIG. 4 is a schematic front view showing an intermediate film applicable to the present invention.

5A and 5B show still another intermediate film applicable to the present invention, wherein FIG. 5A is a schematic front view and FIG. 5B is a schematic side view.

FIGS. 6A and 6B show still another intermediate film applicable to the present invention, wherein FIG. 6A is a schematic front view and FIG. 6B is a schematic side view.

[Explanation of symbols]

 F Flexible wiring body 1 Base film (insulating film) 3 Cover film (insulating film) 5 Intermediate film 5A Opening 5B Notch 5C Annular part (part that divides opening) 5D Neck 15 Intermediate film 25 Intermediate film 35 Intermediate film 45 Intermediate the film

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Murakami 1-14 Nishisuehirocho, Yokkaichi-shi, Mie Sumitomo Wiring Systems, Ltd. (56) References JP-A-64-48336 (JP, A) JP-A-10 -261323 (JP, A) JP-A-62-200791 (JP, A) JP-A-3-34390 (JP, A) JP-A-7-298453 (JP, A) JP-A-8-17259 (JP, A) 5) Field survey (Int. Cl. ⁷ , DB name) H01B 7/08 H01B 13/00 525 H05K 1/02 H05K 3/10

Claims (2)

(57) [Claims] A conductive wire forming a conductive pattern including a conductive crossing portion crossing in an electrically connected state, an insulating crossing portion crossing in an electrically insulated state, and a pair of laminating conductive wires. An insulating film is interposed between one conductive wire and the other conductive wire constituting the conductive intersection and the insulating intersection, has an opening that opens the conductive intersection, and maintains an insulating state by interposing the insulating intersection. A flexible intermediate wiring, wherein the intermediate film has cutouts formed at intervals in the longitudinal direction for preventing stress from being concentrated on a portion defining the opening. body. 2. An opening interposed between one conducting wire and another conducting wire which constitutes an element of a flexible wiring body and having a conductive crossing portion intersecting in an electrically connected state, and opening the conductive crossing portion. An intermediate film in the form of a strip, wherein cutouts for preventing stress from concentrating on portions defining the opening are formed at intervals in the longitudinal direction.