JPH0997967A - Manufacture of flexible printed-wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a flexible printed-wiring board by which the mounting process of a reinforcement plate is simplified and whose manufacturing costs are reduced by a method wherein ultraviolet rays are radiated, an ultraviolet curing resin is hardened only in the region of an opening part on the printed- wiring board, the ultraviolet curing resin which is unhardened is removed and only the hardened ultraviolet curing resin is left as the reinforcement plate. SOLUTION: The face of a flexible printed-wiring board 1 on which an opening part is formed in a prescribed position is coated with an ultraviolet curing resin 13. A mask 15 which passes ultraviolet rays only in the opening part in the prescribed position is placed in a prescribed position on the coated ultraviolet curing resin 13. After that, ultraviolet rays are then irradiated from the side of the mask 15. The ultraviolet curing resin 13 is hardened only in the opening part. Then, the ultraviolet curing resin 13 which is unhardened is removed out of the coated ultraviolet curing resin 13. Only the hardened ultraviolet curing resin 13 is left so as to be used as a reinforcement plate. Thereby, the mounting process of the reinforcement plate can be simplified, and the manufacturing cost of the flexible printed-wiring board can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a flexible printed wiring board used for wiring of electronic devices and the like, and more particularly to a step of attaching a reinforcing plate for improving the partial mechanical strength of the flexible printed wiring board. The present invention relates to a method for manufacturing a flexible printed wiring board that can be simplified.

[0002]

2. Description of the Related Art Conventionally, a flexible printed wiring board used for wiring an electronic device or the like has a low mechanical strength by itself, and is therefore made by laminating a reinforcing plate made of polyimide or the like.

When manufacturing a flexible printed wiring board to which such reinforcing plates are attached, an adhesive is first applied to one surface of a plate-shaped reinforcing plate material. Then, the plate-shaped reinforcing plate material is formed into a predetermined shape by router processing using an NC drill or punching processing using a mold, and hole processing is performed to form a reinforcing plate. After that, a reinforcing plate is fitted to a predetermined position of the flexible printed wiring board so that the surface coated with the adhesive is faced, and the printed wiring board and the reinforcing plate are bonded to each other by applying only pressure or pressure and heat.

[0004]

However, in the conventional method for manufacturing a printed wiring board, a reinforcing plate coated with an adhesive is processed by using an NC drill or a die, and the adhesive is applied to the NC drill or the die. However, if this is left as it is, the workability deteriorates. Therefore, the adhesive attached to the NC drill or the mold must be cleaned at a predetermined cycle, and there is a problem that the work efficiency decreases.

Further, when the reinforcing plate is processed by using a mold, since one mold is used for one kind of flexible printed wiring board, there is a problem that the cost becomes high.

Further, when the printed wiring board and the reinforcing plate are attached to each other, a jig having a positioning pin provided at a predetermined position is required, but one jig is used for each kind of printed wiring board. However, there is a problem that the cost becomes high. Further, since the positioning pin determines the positioning accuracy, a high accuracy is required for the installation position. However, since the positioning pin rattles during use, new positioning is performed at a predetermined cycle. There is a problem that it is necessary to replace with a tool, and the cost is increased accordingly.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for manufacturing a flexible printed wiring board which can simplify the step of attaching the reinforcing plate and reduce the manufacturing cost. .

[0008]

In order to achieve the above object, a first invention of the present application is to provide an application step of applying an ultraviolet curable resin to at least one surface of a flexible printed wiring board, and an opening at a predetermined position. A mask that is provided and passes only ultraviolet rays through this opening is placed at a predetermined position on the applied ultraviolet curable resin, and then ultraviolet rays are radiated from this mask side so that only the area of the openings is ultraviolet cured. An ultraviolet irradiation step of curing the mold resin, and a removal step of removing the uncured ultraviolet curable resin from the applied ultraviolet curable resin and leaving only the cured ultraviolet curable resin as a reinforcing plate. That is the summary.

In the method for manufacturing a flexible printed wiring board according to the first aspect of the present invention, an ultraviolet curable resin is applied to at least one surface of the flexible printed wiring board,
An opening is provided at a predetermined position, and a mask that allows only ultraviolet rays to pass through the opening is placed at a predetermined position on the applied ultraviolet curable resin, and then ultraviolet rays are radiated from the mask side. The ultraviolet curable resin is cured only in the area of the opening. Then, of the applied ultraviolet curable resin, the uncured ultraviolet curable resin is removed, and only the cured ultraviolet curable resin is left to serve as a reinforcing plate. As a result, the step of attaching the reinforcing plate can be simplified and the manufacturing cost can be reduced.

A second aspect of the present invention is to apply an ultraviolet curable resin to a predetermined position on at least one surface of the flexible printed wiring board, and to irradiate ultraviolet rays from the applied ultraviolet curable resin side. Then, the gist of the present invention is to have an ultraviolet irradiation step of curing the ultraviolet curable resin.

In the method for manufacturing a flexible printed wiring board according to the second aspect of the present invention, after the ultraviolet curable resin is applied to a predetermined position on at least one surface of the flexible printed wiring board, the ultraviolet curable resin is applied. Ultraviolet rays are irradiated from the coated surface side to cure the ultraviolet curable resin to form a reinforcing plate. As a result, the step of attaching the reinforcing plate can be simplified and the manufacturing cost can be reduced.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing each step for explaining the first embodiment of the method for manufacturing a flexible printed wiring board according to the present invention.

As shown in FIG. 1A, when manufacturing the flexible printed wiring board of the first embodiment, first, the flexible printed wiring board 1 is made of polyimide or the like as a substrate.
Create 1.

Next, as shown in FIG. 1B, an ultraviolet curable resin (hereinafter referred to as a UV curable resin) 13 is applied to one surface of the flexible printed wiring board 11 (application step).

The UV curable resin 13 may be applied to the entire one surface of the flexible printed wiring board 11 or may be applied only to the peripheral portion of the area where the reinforcing plate is attached. The UV curable resin 13 may be applied by screen printing or may be applied to a predetermined area by using a nozzle. The coating thickness of the UV curable resin 13 is 25 to 3 when the thickness of the flexible printed wiring board 11 is about 200 (μm).
5 (μm).

Next, as shown in FIG. 1C, an opening is provided in advance at the position where the reinforcing plate is provided, and a mask 15 which allows only the opening to pass ultraviolet rays is placed on the upper surface of the UV curable resin 13. After that, by irradiating the mask 15 side with ultraviolet rays, only the region of the opening is UV cured resin 1
3 is cured (ultraviolet ray irradiation step).

As a result, the UV curable resin 13 is molded into the resin uncured portion 13a and the resin cured portion 13b.

Next, the resin uncured portion 1 shown in FIG.
3a is removed by spraying water, for example, and FIG.
As shown in (d), only the resin cured portion 13b is left (removal step).

Although the resin uncured portion 13a is removed by spraying water toward the resin uncured portion 13a, the removal method is not limited to this, and the resin uncured portion 1 may be used.
The resin uncured portion 13a may be removed by immersing it in a solution that dissolves 3a (having a solubility that does not dissolve the resin cured portion 13b).

Thus, the resin cured portion 13b is attached to the flexible printed wiring board 11 as a reinforcing plate.
If high precision is required for the mounting shape of the resin cured portion 13b as the reinforcing plate due to the positional relationship of the electronic devices placed on the flexible printed wiring board 11, after removing the resin ineffective portion 13a (It may be before removing the resin uncured portion 13a), or the outer shape may be processed into a predetermined shape by a mold.

As described above, in the method for manufacturing a flexible printed wiring board according to the first embodiment, the UV curable resin 13 is applied to one surface of the flexible printed wiring board 11 and the mask 15 is used to UV cure only a predetermined area. The resin 13 is cured to form the resin cured portion 13b, which is used as the reinforcing plate. Therefore, the step of attaching the reinforcing plate can be simplified and the manufacturing cost can be reduced.

FIG. 2 is a sectional view showing each step for explaining the second embodiment of the method for manufacturing a flexible printed wiring board according to the present invention. In the figure, the same components as those shown in FIG. 1 are denoted by the same symbols, and detailed description is omitted.

As shown in FIG. 2A, when manufacturing the flexible printed wiring board according to the second embodiment, first, the flexible printed wiring board 1 is made of polyimide or the like as a substrate.
Create 1.

Next, as shown in FIG. 2B, a screen mask 21 having openings at predetermined positions is placed on one surface of the flexible printed wiring board 11.
Then, the UV curable resin 13 is applied on the screen mask 21, and a thin plate-shaped squeegee is slid on the screen mask 21 to apply the UV curable resin 13 at a predetermined position and at a predetermined thickness. For example, when the thickness of the flexible printed wiring board 11 is about 200 (μm), U
The thickness of the V-curable resin 13 is 25 to 35 (μm).

Then, as shown in FIG. 2 (c), the UV curable resin 1 is irradiated with ultraviolet rays from the UV curable resin 13 side.
3 is cured (ultraviolet ray irradiation step). This allows UV
The cured resin 13 is cured to form the resin cured portion 13b.

Thus, the resin cured portion 13b is attached to the flexible printed wiring board 11 as a reinforcing plate.

If high precision is required for the mounting shape of the resin cured portion 13b as the reinforcing plate due to the positional relationship of the electronic equipment mounted on the flexible printed wiring board 11, the resin is irradiated with ultraviolet rays to irradiate the resin. After molding the hardened portion 13b, the outer shape may be processed into a predetermined shape by a mold.

As described above, in the flexible printed wiring board manufacturing method of the second embodiment, the screen mask 21 is used.
The UV curable resin 13 is applied to a predetermined position of the flexible printed wiring board 11 by using, and the UV curable resin 13 is irradiated with ultraviolet rays to be cured to form a resin cured portion 13b, which is used as a reinforcing plate. Therefore, the step of attaching the reinforcing plate can be simplified and the manufacturing cost can be reduced.

In the above embodiment, the case where the resin cured portion 13b as a reinforcing plate is formed on one surface of the flexible printed wiring board 11 has been described as an example, but the present invention is not limited to this. Alternatively, the resin cured portions 13b as reinforcing plates may be formed on both surfaces of the flexible printed wiring board 11.

[0030]

As described above, in the method for manufacturing a flexible printed wiring board according to the first aspect of the present invention, the ultraviolet curable resin is applied to at least one surface of the flexible printed wiring board, and the ultraviolet rays pass only through the openings. After the mask is placed at a predetermined position on the applied ultraviolet curable resin, the ultraviolet curable resin is cured only in the area of the opening by irradiating the mask with ultraviolet rays, and the uncured resin is uncured. Since the ultraviolet curable resin is removed and only the cured ultraviolet curable resin is left to form the reinforcing plate, the step of attaching the reinforcing plate can be simplified and the manufacturing cost can be reduced.

In the method for manufacturing a flexible printed wiring board according to the second aspect of the present invention, the ultraviolet curable resin is applied to a predetermined position on at least one surface of the flexible printed wiring board, and then the ultraviolet curable resin is applied. Since the ultraviolet curing resin is cured by irradiating ultraviolet rays from the side of the surface to be cured to form the reinforcing plate, the step of attaching the reinforcing plate can be simplified and the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a first method of manufacturing a flexible printed wiring board.
It is sectional drawing of each process for describing embodiment.

FIG. 2 is a second method of manufacturing a flexible printed wiring board.
It is sectional drawing of each process for describing embodiment.

[Explanation of symbols]

 11 flexible printed wiring board 13 UV curable resin 13a resin uncured portion 13b resin cured portion 15 mask 21 screen mask

Claims (3)

[Claims] 1. A coating step of coating an ultraviolet curable resin on at least one surface of a flexible printed wiring board, and an opening is provided at a predetermined position, and a mask that allows ultraviolet rays to pass through only the opening is coated. After being placed at a predetermined position on the ultraviolet curable resin, an ultraviolet irradiation step of curing the ultraviolet curable resin only in the area of the opening by irradiating ultraviolet rays from the mask side, and the applied ultraviolet curable resin A method of manufacturing a flexible printed wiring board, comprising: a step of removing an uncured ultraviolet curable resin among the resins and leaving only the cured ultraviolet curable resin as a reinforcing plate. 2. An applying step of applying an ultraviolet curable resin to a predetermined position on at least one surface of a flexible printed wiring board, and irradiating the ultraviolet ray from the applied ultraviolet curable resin side to the ultraviolet curable resin. A method of manufacturing a flexible printed wiring board, comprising: 3. The method for manufacturing a flexible printed wiring board according to claim 2, wherein in the applying step, an ultraviolet curable resin is applied at a predetermined position by screen printing.