JPS63229893A - Printed wiring board and manufacture of the same - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a circuit that is divided into a fixed part that is fixed to a base material and a flexible part that cannot be supported by the base material and has flexibility. <Conventional technology> Conventionally, a fixed printed wiring member that is fixed to another member and a flexible printed wiring member that is not fixed to other members are combined into a single unit. Various types of printed wiring boards are known in which the printed wiring boards can meet the demand for smaller and lighter equipment. For example, FIG. 4 shows a typical example of the above-mentioned printed wiring board. In other words, a resist pattern corresponding to a desired electric circuit pattern is formed on a copper-clad laminate for printed circuits, and then an etching process is performed. Then, the resist pattern is removed to obtain a fixed printed wiring member 24 having a desired electric circuit pattern. On the other hand, an adhesive is applied to the base film, and a copper foil is bonded to the base film using a heating roll to obtain a flexible printed wiring member material. Then, a resist pattern corresponding to a desired electric circuit pattern is formed on this flexible printed wiring material raw material, and after an etching process is performed, the desired electric circuit pattern is formed by removing the resist pattern. A flexible printed wiring member 23 is obtained. Then, this flexible printed wiring member 2
3, an anisotropic conductive film 26 is attached to the fixed printed wiring members 24, a pair of the fixed printed wiring members 24 is prepared, and the fixed printed wiring members 24 of the pair are prepared.
There is one in which each circuit of the visible printed wiring member 23 and the fixed printed wiring member 24 is connected by thermocompression bonding the flexible printed wiring member 23 so as to span between the two. In each of the printed wiring members 23 and 24, 25 is a circuit pattern layer, 25a is a conductive pattern layer, and 25b is an insulating pattern layer. In addition, instead of the flexible printed wiring member 23 with the anisotropic conductive film 26 attached,
There is also one in which each circuit of a pair of fixed printed wiring members 24 is connected using a film-like electrode connector disclosed in Japanese Patent No. 85.

<Problems to be Solved by the Invention> However, in the structure described above, the printed wiring board is formed by bonding the fixed printed wiring member and the flexible printed wiring member, so the fixed printed wiring board is There were problems such as a lack of reliability, such as an increase in connection resistance at the connection between the circuit of the wiring member and the circuit of the flexible printed wiring member, and an increase in resistance value in environmental tests. Furthermore, since each circuit is connected by pasting together a fixed printed wiring member and a flexible printed wiring member, there is a problem in aligning the wiring patterns to be connected with high precision.

Furthermore, in the method for manufacturing a printed wiring board as described above, the fixed printed wiring member and the flexible printed wiring member are once finished as individual products, and then the two members are bonded together to form the printed wiring board. There is.

Therefore, when manufacturing each printed wiring member, depending on the presence or absence of a member that supports the circuit pattern layer of the printed wiring member, processing methods and processing equipment such as printing, etching, and polishing may be different, making it time-consuming and reducing production efficiency. There was a problem with it being bad.

Therefore, an object of the first invention is to solve the above-mentioned problem, and it is possible to integrally form the circuit of the fixed part and the circuit of the flexible part, and there is no need to connect the two. It is an object of the present invention to provide a printed wiring board that increases the reliability of the connection between the two and allows the connection to be performed with high accuracy.

Moreover, the second and third objects of the invention are to solve the above-mentioned problems and to provide a method for manufacturing a printed wiring board with high production efficiency.

Means for Solving the Problems> In order to achieve the above object, the first invention divides the circuit pattern layer into a fixed part and a flexible part, and attaches a base material to the fixed part via an adhesive layer. It was configured to be fixed. That is, a circuit sheet comprising a base sheet and a circuit pattern layer formed on the base sheet and divided into a fixed part and a flexible part, and a circuit sheet arranged on one side of the fixed part of the circuit sheet. It was configured to include an adhesive layer and a base material fixed to the adhesive layer.

Moreover, in the second aspect of the present invention, a circuit sheet for a printed wiring board, which includes a circuit pattern layer of a printed wiring board on a base sheet, is fixed to a base material. That is, a circuit sheet comprising a base sheet and a circuit pattern layer formed on the base sheet and divided into a fixed part and a flexible part is configured such that the base material is attached to the fixed part of the circuit sheet. Na.

Further, the third invention provides a circuit sheet for a printed wiring board comprising a circuit pattern layer of a printed wiring board on a base sheet, which is inserted into a mold and fixed, and a circuit pattern layer of the circuit sheet is placed on the circuit pattern layer side of the circuit sheet. The circuit pattern layer was fixed to the base material by resin molding.

That is, a circuit sheet comprising a base sheet and a circuit pattern layer formed on the base sheet and divided into a fixed part and a flexible part is placed in a mold, and the fixed part of the circuit sheet is placed in the mold. It was positioned so as to face the cavity of the mold, and a molten synthetic resin was injected into the cavity of the molding die to form a synthetic resin base material on the cavity side of the fixed portion of the circuit sheet.

According to the first invention, the base sheet and the circuit pattern layer are divided into a fixed part and a flexible part, and the fixed part is supported by the base material, so that the circuit pattern layer The connection reliability between the circuit in the fixed part and the circuit in the flexible part is excellent, and the printed wiring board can be made with high precision.

That is, instead of forming a fixed part and a flexible part by connecting each circuit of a printed wiring member manufactured separately, the fixed part and flexible part are integrated from the beginning to form a circuit pattern layer. Since there is no need to connect the two in post-processing,
Therefore, no connection resistance can occur. Further, according to the first invention, the circuit of the fixed part and the circuit of the flexible part can be connected inside the circuit pattern layer and are not exposed outside the circuit pattern layer, so that the circuit of the fixed part and the flexible part can be connected. It becomes possible to design a circuit with high density between the parts. In other words, in the conventional type, the circuit in the fixed part of the circuit pattern layer and the circuit in the flexible part were connected outside the circuit pattern layer, so the connection part was exposed and the connection between the fixed part and the flexible part was made. This hindered the ability to increase the density of circuit designs.

According to the second invention, there is no need for any connection work to connect the fixed part and the flexible part in a subsequent process.

In addition, even if the circuit sheet is later divided into a fixed part and a flexible part, it can be treated as a single member before attaching the base material to the fixed part, and when processing this circuit sheet, it can be treated as a single member. There is no need to use different processing methods and processing equipment for the fixed part and the flexible part. Therefore, the production efficiency of printed wiring boards can be dramatically improved.

According to the third invention, there is no need for any connection work to connect the fixed part and the flexible part in a subsequent process. Furthermore, even if the circuit sheet is later divided into a fixed part and a flexible part, it can be treated as one member before attaching the base material to the fixed part, and when processing this circuit sheet,
There is no need to use different processing methods and processing equipment for the fixed part and the flexible part. Furthermore, the base material and the fixing portion of the circuit sheet can be fixed together at the same time as the base material is molded, and the work of fixing the circuit sheet and the base material becomes unnecessary. Therefore, the production efficiency of printed wiring boards can be further dramatically improved.

<Example> Examples according to the present invention will be described in detail below based on FIGS. 1 to 3.

As shown in the cross section of FIG. 1, the printed wiring board 1 according to this embodiment has a circuit pattern layer 2 formed on a base sheet 6, and is divided into a fixed part A and a flexible part B, and each fixed part is divided into a fixed part A and a flexible part B. An adhesive layer 3 is formed on part A, and a base material 4 supporting each fixing part A of the circuit sheet 5 is fixed to each adhesive layer 3.

The circuit pattern layer 2 is configured into two layers by arbitrarily combining a conductive pattern layer 2a and an insulating pattern layer 2b. These two layers are constructed on the base sheet 6 to form the circuit sheet 5. This circuit sheet 5 is divided into a pair of fixed parts A that can each be fixed to the base material 4, and a flexible part B that is located between the pair of fixed parts A and has visibility without being fixed to the base material 4. Separate.

Each adhesive layer 3 fixes each fixed portion A of the circuit sheet 5 to each base material 4.

Further, each base material 4 supports each fixed portion A of the circuit sheet 5 via each adhesive layer 3.

According to the above configuration, the flexible part B of the circuit sheet 5 that cannot be supported by the base material 4 is located at the fixed part ArHff of the circuit sheet 5 supported by the pair of base materials 4, so that the circuit sheet By bending the base material 5 at the flexible portion B, each base material 4 can be fixed to a desired installation location of the device, such as the bottom surface and side wall of a box-like casing of the device.

According to the above embodiment, the circuit sheet 5 is divided into the fixed part A and the flexible part B, and the fixed part A is supported on the base material 4, so that the circuit of the fixed part A and the flexible part B is already connected to the circuit when the circuit sheet 5 is formed, and the connection reliability between the two is excellent, and the connection between the two can be made highly accurate.

It should be noted that this invention is not limited to the above embodiments, but can be implemented in various other ways. For example, in the printed wiring board l, the fixed part A of the circuit sheet 5 is one circuit sheet 5.
The flexible part B of the circuit sheet 5 is not limited to two pieces, but may be one piece or three or more pieces. One end of the flexible part B may be connected to the fixed part A, and the other end may be a free end. Alternatively, only the center portion of the circuit sheet 5 may be supported by the fixed portion A, and both ends may be made into the flexible portions B. In addition, the circuit pattern layer 2
is not limited to two layers, and may be formed with any number of layers.Also, even if the circuit pattern layer 2 is formed only on one side of the base sheet 6 on the base material 4 side, or on the opposite side of the base material 4, It may be formed only on one side, or it may be formed on both sides of the base sheet 6. Further, instead of eliminating the adhesive layer 3, the base material 4 itself may be selected to have an adhesive function, and the base material 4 may be directly fixed to the fixed part A of the circuit sheet 5 by thermocompression bonding or the like. .

Next, a method for manufacturing printed wiring board 1 will be explained.

This method uses a circuit sheet 5. That is, as shown in FIG. 2, the circuit sheet 5 is divided into a fixed part A and a flexible part B, each consisting of a base sheet 6 and a circuit pattern layer 2 formed on the base sheet 6. An adhesive layer 3 is formed on each fixing part A of the circuit sheet 5, and each fixing part A is attached to each base material 4 using each adhesive layer 3 by thermocompression bonding.

Note that by using a pressure-sensitive adhesive layer 3, adhesion may be performed by pressure treatment.

In this way, printed wiring board 1 is formed.

According to this method, there is no need for a connection operation to connect the fixed part A and the flexible part B in a subsequent process. In addition, the circuit sheet 5 is
Even if it is later divided into a fixed part A and a flexible part B, it can be treated as one member before attaching the base material 4 to the fixed part A, and when processing this circuit sheet 5, the fixed part There is no need to use different processing methods and processing equipment for the flexible part A and the flexible part B. Therefore, the production efficiency of printed wiring boards can be dramatically improved.

Other methods for manufacturing printed wiring boards include the following. That is, as shown in FIG. 3, this is a method in which the base material 4 is directly molded onto the adhesive layer 3 of the circuit sheet 5 using a base material molding die. As shown in FIG. 3(a), the base material molding mold consists of a fixed mold 9a supported by a fixed plate 9 and a movable mold 10a supported by a movable plate 10, and a circuit sheet support bag is attached to the movable mold 10a. fil. The support device 11 supports the base sheet 6 of the circuit sheet 5 and is movable! 110 toward the fixed platen 9, the movable mold 10a and the fixed mold 9a are closed, and the base sheet 6 is punched out. As shown in FIG. 3(b), the flexible circuit sheet 5 is Part B is brought into contact with the inner surface of the movable mold 10a, while the surface of the circuit sheet 5 on the adhesive layer 3 side faces into the cavity 8 of the fixed mold 9a, and the flexible part B of the circuit sheet 5 is fixed to the movable mold 10a. It is fixed by sandwiching it with the mold 9a.

Thereafter, molten synthetic resin is injected into the cavity 8 to perform injection molding. After both molds 9a and 10a are cooled and the molten synthetic resin is solidified, the movable platen 10 is moved relative to the fixed platen 9 to open the mold, and the molded product is taken out from the fixed mold 9a, and the printed wiring board, That is, a printed wiring board is completed in which the injection-molded base material 4 is integrally fixed to the surface on the circuit pattern layer 2 side. In this case, the injection conditions vary depending on the type of molten resin and the shape of the mold, but the mold temperature is 5.
0 to 180°C, and the resin temperature is preferably about 250 to 400°C. In the manufacturing process, the base material 4 is molded by injecting the molten synthetic resin in the molding die, and then the mold is further closed in the mold to thermocompress the base material 4 and the circuit sheet 5 to form the base material. The adhesion between the material 4 and the circuit sheet 5 may be made stronger, and the molded product may be subjected to thermocompression bonding after being taken out from the mold rather than inside the molding mold. You may also do this. Note that the adhesive layer 3 of the circuit sheet 5 may be omitted if the molten synthetic resin can adhere to the circuit sheet 5.

According to the above method, there is no need for a connection operation to connect the fixed part A and the flexible part B in a subsequent process. In addition, the circuit sheet 5 is
Even if it is later divided into a fixed part A and a flexible part B, it can be treated as one member before attaching the base material 4 to the fixed part A, and when processing this circuit sheet 5, the fixed part There is no need to use different processing methods and processing equipment for A and flexible portion B, etc. Furthermore, the base material 4 and the fixing portion A of the circuit sheet 5 can be fixed simultaneously with the molding of the base material 4. Therefore, the production efficiency of printed wiring boards can be further dramatically improved.

Product example> Silver paste was screen printed in the circuit pattern on a 38 μm thick polyethylene terephthalate base sheet, and then insulation paste and silver paste were sequentially screen printed to produce a circuit sheet for printed wiring boards. .

This circuit sheet was aligned and placed in an injection mold, the mold was closed, and polyethylene terephthalate resin was injected under the following conditions. After the resin was cooled and solidified, the mold was opened and the molded substrate was taken out.

The injection conditions are as follows. The injection molding machine uses Nippon Steel's rupture JC-150SA, and the mold temperature is 100-12
0℃, cylinder temperature 260~300℃, injection pressure 800kg/cm", holding pressure 500kg/0m2
The injection speed was 70% of the maximum speed of the injection molding machine, and the screw rotation speed was 50 r, p, ta.

As a result, a printed wiring board was formed in which the two fixed parts of the circuit pattern layer were each supported by the base material, and the flexible part was flexibly positioned between the re-fixed parts.

<Effect of the invention> This invention has the following excellent effects.

According to the first invention, the base sheet and the circuit pattern layer are divided into a fixed part and a flexible part, the fixed part is supported by the base material, and the fixed part and the flexible part are integrated from the beginning. Since the base sheet and the circuit pattern layer are formed on the substrate, there is no need to connect the two in post-processing, and therefore connection resistance cannot occur. In addition, the circuit in the fixed part and the circuit in the flexible part can be connected inside the circuit pattern layer.
Since the circuit pattern layer is not exposed to the outside, it is possible to design a circuit with high density between the fixed part and the flexible part.

According to the second invention, since the base material is attached to the circuit sheet formed in advance, there is no need for any connection work to connect the fixed part and the flexible part in a subsequent process. In addition, the circuit sheet can be handled as a single member before the base material is attached to the fixed part, and when processing this circuit sheet, the processing method and processing equipment can be adjusted between the fixed part and the flexible part. There is no need to make any difference,
The production efficiency of printed wiring boards can be dramatically improved.

According to the third invention, since the base material is formed by injection molding on a circuit sheet that has been formed in advance, there is no need for any connection work to connect the fixed part and the flexible part in a post-process. In addition, the circuit sheet can be handled as a single member before the base material is attached to the fixed part, and when processing this circuit sheet, the processing method and processing equipment can be adjusted between the fixed part and the flexible part. There is no need to make any difference.Furthermore, the base material and the fixing portion of the circuit sheet can be fixed together at the same time as the base material is molded, and the work of fixing the circuit sheet and the base material becomes unnecessary. Therefore, the production efficiency of printed wiring boards can be further dramatically improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a printed wiring board according to an embodiment of the present invention, FIG. 2 is a sectional view of a circuit sheet used in manufacturing the printed wiring board, and FIGS. 3(a) and (b). FIG. 4 is a cross-sectional side view of each molding die in an open state and a closed state, and FIG. 4 is a cross-sectional view of a conventional printed wiring board. DESCRIPTION OF SYMBOLS 1... Printed wiring board, 2... Circuit pattern layer, 2a.
... Conductive pattern layer, 2b... Insulating pattern layer, 3.
...Adhesive layer, 4...Base material, 5...Circuit sheet, 6.
...Base sheet, 8...Cavity, 9...Fixed plate, 9a...Fixed type, 10...Movable plate, 10a...Movable type, 11...Circuit sheet support device, 21...・Adhesive layer, 22... Base material, 23... Flexible printed wiring member,
24...Fixing printed wiring member, 25...Circuit pattern layer, 26...Anisotropic conductive film, A...Fixing part, B...
...Flexible part. Patent applicant Nissha Printing Co., Ltd. Printed wiring board Figure 1 Figure 4

Claims (4)

[Claims] (1) A circuit sheet comprising a base sheet (6) and a circuit pattern layer (2) formed on the base sheet (6) and divided into a fixed part (A) and a flexible part (B) ( 5), an adhesive layer (3) disposed on one side of the fixed part (A) of the circuit sheet (5), and a base material (4) fixed to the adhesive layer (3). A printed wiring board characterized by: (2) A circuit sheet comprising a base sheet (6) and a circuit pattern layer (2) formed on the base sheet (6) and divided into a fixed part (A) and a flexible part (B) ( 5) A method for manufacturing a printed wiring board, characterized in that the base material (4) is attached to the fixed part (A) of the circuit sheet (5). (3) The method for manufacturing a printed wiring board according to claim 2, wherein the fixing part (A) of the circuit sheet (5) is attached to the base material (4) by thermocompression bonding. (4) A circuit sheet comprising a base sheet (6) and a circuit pattern layer (2) formed on the base sheet (6) and divided into a fixed part (A) and a flexible part (B) ( 5) into the molding molds (9a, 10a).
The fixed part (A) of the above-mentioned molding die (9a) has a cavity (
8), and inject molten synthetic resin into the cavity (8) of the molding die (9a) to synthesize it on the cavity (8) side of the fixed part (A) of the circuit sheet (5). A method for manufacturing a printed wiring board, characterized in that a resin base material (4) is formed.