JP2017005032A - Printed circuit body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly-reliable print circuit body capable of suppressing generation of breaking and cracks of a conductive layer at a bent position.SOLUTION: A print circuit body 11 comprises: a film-like base material 21 having flexibility; and a conductive layer 22 formed by printing a conductive material on the base material 21. On the conductive layer 22, a thick part 22a thicker than other positions is provided at a bent position K where the print circuit body is bent.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a printed circuit body.

  As a circuit body capable of bending wiring, there is known a flexible wiring board (FPC) in which a conductive pattern made of a conductive layer is formed by etching on a flexible base insulating layer (see, for example, Patent Document 1). .

Japanese Patent Laid-Open No. 2005-210034

  In recent years, printed circuit bodies that have a higher degree of freedom in circuit formation than flexible wiring boards (FPC) and can be manufactured at low cost have been used. This printed circuit body is made of a conductive material made of conductive ink such as silver or copper or a conductive paste on a flexible base material made of a resin film such as polyimide (PI) or polyethylene terephthalate (PET). The conductive layer is formed by printing by a printing method such as inkjet printing or screen printing.

  However, in this printed circuit body, the circuit part is made of metal particles, and the density is lower than that of the bulk. May occur.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a highly reliable printed circuit body in which occurrence of disconnection and cracks in a conductive layer at a bent position is suppressed.

In order to achieve the above-described object, a printed circuit body according to the present invention is characterized by the following (1) to (2).
(1) A printed circuit body having a flexible film-like substrate and a conductive layer formed by printing a conductive material on the substrate,
The printed circuit body, wherein the conductive layer is provided with a thick portion at a bending position where the printed circuit body is bent, which is thicker than other positions.
(2) The printed circuit body according to (1), wherein a flexible film-like cover is attached to the base material and the conductive layer.

In the printed circuit body of the above (1), the thick portion is provided at a bending position where a load acts on the conductive layer by being bent when being routed. Therefore, the degree of freedom of circuit formation is high, the circuit can be manufactured at low cost, and defects such as disconnection or cracks caused by bending can be suppressed, and high reliability can be obtained.
In addition, since the thickness of only the portion where the load due to bending acts is increased, the amount of conductive material used is suppressed and the cost is reduced compared to the case where the entire thickness of the conductive layer is increased. Strength can be increased. In addition, since the resistance value at the bent position can be lowered, the width of the conductive layer at the bent position can be suppressed.
In the printed circuit body of the above (2), peeling of the conductive layer from the base material can be further reliably suppressed by the cover attached to the base material, and the reliability can be further improved.

  ADVANTAGE OF THE INVENTION According to this invention, the reliable printed circuit body by which generation | occurrence | production of the disconnection and crack of the conductive layer in a bending position was suppressed can be provided.

  The present invention has been briefly described above. Further, the details of the present invention will be further clarified by reading through a mode for carrying out the invention described below (hereinafter referred to as “embodiment”) with reference to the accompanying drawings. .

FIG. 1 is a diagram illustrating a printed circuit body according to the present embodiment, in which FIG. 1A is a perspective view of the printed circuit body before wiring, and FIG. 1B is a view in FIG. It is AA sectional drawing. 2A and 2B are diagrams showing the printed circuit body according to the present embodiment, in which FIG. 2A is a perspective view of the printed circuit body after routing, and FIG. 2B is a diagram in FIG. It is BB sectional drawing.

Hereinafter, an example of an embodiment according to the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a printed circuit body according to the present embodiment, in which FIG. 1A is a perspective view of the printed circuit body before wiring, and FIG. 1B is a view in FIG. It is AA sectional drawing. 2A and 2B are diagrams showing the printed circuit body according to the present embodiment, in which FIG. 2A is a perspective view of the printed circuit body after routing, and FIG. 2B is a diagram in FIG. It is BB sectional drawing.

  As shown in FIGS. 1A and 1B, the printed circuit body 11 according to the present embodiment is formed in a sheet shape. The printed circuit body 11 is bent at a predetermined position at the bent position K, and is bent at the bent position K.

  As shown in FIGS. 2A and 2B, the printed circuit body 11 is routed along the surface of the housing 1, for example. The casing 1 has corners 2 and corners 3, and the printed circuit body 11 routed along the surface of the casing 1 has a bending position K arranged at the corners 2 and corners 3. Is done. Thereby, the bending position K of the printed circuit body 11 is bent at the corner portion 2 and the corner portion 3.

  A connector 4 is mounted on the printed circuit body 11. For example, a mating connector (not shown) provided in a wire harness is connected to these connectors 4.

  The printed circuit body 11 includes a base material 21, a conductive layer 22 provided on the base material 21, and a cover 23 bonded to the surface of the base material 21 via the conductive layer 22.

  The base material 21 is formed from a resin film having flexibility and insulating properties. For example, a resin film formed from polyimide (PI), polyethylene terephthalate (PET), or the like is used as the resin film to be the base material 21.

  The conductive layer 22 is formed of a conductive material such as conductive ink or conductive paste containing particles such as silver and copper. The conductive layer 22 is formed by printing on the base material 21 by a printing method such as inkjet printing or screen printing. A predetermined circuit pattern is formed on the base material 21 by the conductive layer 22. The connector 4 mounted on the printed circuit body 11 has terminals therein, and these terminals are electrically connected to a conductive layer 22 that forms a circuit pattern.

  The cover 23 is formed of a flexible and insulating resin film made of, for example, polyimide (PI), polyethylene terephthalate (PET), or the like, like the base material 21. The cover 23 is bonded to the surface of the base material 21 on which the conductive layer 22 is formed. Thereby, the upper surface side of the conductive layer 22 on the substrate 21 is covered with the cover 23.

  The printed circuit body 11 has a thick portion 22 a in the conductive layer 22. The thick portion 22 a is provided at the bending position K in the printed circuit body 11. In the conductive layer 22, the thickness T1 of the thick portion 22a is thicker than the thickness T2 at other positions.

  In order to manufacture the printed circuit body 11 described above, first, a conductive material such as a conductive ink or a conductive paste is printed on a substrate 21 made of a resin film by a printing method such as inkjet printing or screen printing. A conductive layer 22 is formed. At this time, printing is performed so that the conductive layer 22 is thicker than the other portions at the bending position K. Thereby, the thick portion 22 a is formed in the conductive layer 22. After the conductive material is dried and cured, a cover 23 is laminated on the surface of the base material 21 on which the conductive layer 22 is formed, and is bonded to the surface of the base material 21.

  The printed circuit body 11 manufactured in this way is bent along the corners 2 and the corners 3 of the housing 1 at the bending position K and routed in the housing 1. At this time, at the bending position K of the printed circuit body 11, a load such as a tensile force or a compressing force acts on the conductive layer 22 due to a difference in bending radius. However, the printed circuit body 11 has a thick portion 22a in which the thickness of the conductive layer 22 is thicker than other portions at the bent position K. At the bent position K, the conductive layer 22 has the thick portion 22a. It will be bent. Therefore, even if a load acts on the conductive layer 22 at the bending position K, the conductive layer 22 does not break.

  Thus, according to the printed circuit body 11 according to the present embodiment, the thick portion 22a is provided at the bending position K where the load is applied to the conductive layer 22 by being bent when being routed. Accordingly, the degree of freedom of circuit formation is high, the circuit can be manufactured at low cost, and defects such as disconnection and cracks occurring in the conductive layer 22 due to a load acting by bending can be suppressed, and high reliability can be obtained. it can.

  Further, since the thickness of only the portion where the load due to bending acts is increased, the bending position can be reduced while suppressing the amount of conductive material used and suppressing the cost compared to the case where the entire thickness of the conductive layer 22 is increased. The strength at K can be increased. Further, since the resistance value at the bending position K can be lowered, the width of the conductive layer 22 at the bending position K can be suppressed.

  In addition, the cover 23 attached to the base material 21 can further reliably prevent the conductive layer 22 from being peeled off from the base material 21, thereby further improving the reliability.

  In the above embodiment, the case where the printed circuit body 11 is routed along the housing 1 has been described as an example. However, the place where the printed circuit body 11 is routed is not limited to the housing 1.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably. In addition, the material, shape, dimensions, number, arrangement location, and the like of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

Here, the features of the above-described embodiment of the printed circuit body according to the present invention will be briefly summarized and listed in the following [1] to [2], respectively.
[1] A printed circuit body (11) having a flexible film-like substrate (21) and a conductive layer (22) formed by printing a conductive material on the substrate (21). ) And
The printed circuit body is characterized in that the conductive layer (22) is provided with a thick portion (22a) thicker than other positions at a bending position (K) where the printed circuit body is bent. .
[2] The printing according to [1], wherein a flexible film-like cover (23) is attached to the base material (21) and the conductive layer (22). Circuit body.

DESCRIPTION OF SYMBOLS 11 Printed circuit body 21 Base material 22 Conductive layer 22a Thick part 23 Cover K Bending position

Claims (2)

A printed circuit body having a flexible film-like substrate and a conductive layer formed by printing a conductive material on the substrate,
The printed circuit body, wherein the conductive layer is provided with a thick portion thicker than other positions at a bending position where the printed circuit body is bent. The printed circuit body according to claim 1, wherein a flexible film-like cover is attached to the base material and the conductive layer.

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