JPH02222593A - Wiring board and manufacture thereof - Google Patents

Abstract

PURPOSE:To make an electric equipment miniature, thin, and lightweight by a method wherein the equipment is equipped with a wiring board provided with a sheet-like insulating base formed of hydrophilic polymer, an insulating resin layer formed on the surface of the insulating base, and a metal conductive circuit etched into a specified pattern. CONSTITUTION:An insulating resin layer 2 is provided to the surface of a sheet- like insulating base 1, conductive metal layer 3 is provided through the intermediary of the resin layer 2, and the obtained laminated body is hot-welded by pressure into an integral structure. Then, the conductive metal layer 3 is etched into a specified pattern to form a conductive circuit 4, and through-holes 5 required for mounting electronic components or the like are bored. Then, the insulating base 1 is made to contain water to become plastic. The base 1 is formed into a specified shape through a plastic working such as bending, drawing, or the like, which is dried up to be formed into an end product provided with a bend 8. By this setup, the shape of the base 1 becomes coincident with that of an electronic equipment board housing space and meets the requirement for the miniaturization of the electronic equipment.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a wiring board and a method for manufacturing the same, and particularly relates to a wiring board that is lightweight and has excellent insulation reliability, and also has excellent plastic workability such as bending and drawing. The present invention relates to a wiring board or a multilayer wiring board, or the Ha method thereof.

[Prior Art] As a base material for wiring boards used in various electronic devices, a rigid insulating board made of glass, ceramic, glass epoxy, etc., has been generally used. Such a wiring board is usually formed into a flat plate shape and is used by being housed in a board storage space formed within an electronic device.

However, it is difficult to plastically process such wiring boards, and in cases where it cannot be used as a single flat board due to the board storage space provided in electronic equipment, two or three boards may be used. A split connection structure is adopted in which the board is divided into multiple parts, such as, and each divided board is connected using cables and connectors. For this reason, such wiring boards inevitably have a large number of components, and are required to be miniaturized and
There has been a problem in that electronic devices that are required to be lighter and thinner may not be able to be adequately addressed.

In addition, in recent years, for the purpose of dealing with miniaturization and thinning, for example, as shown in FIG. 9, a metal plate 101 such as an aluminum plate or a steel plate is used as a base material, and epoxy resin, glass epoxy, A wiring board called a metal base board in which a conductive circuit 103 formed by etching a copper foil or the like in a predetermined pattern is laminated through an insulating layer 102 made of an insulating resin such as polyimide or polyamideimide, or a wiring board called a metal base board;
As shown in the figure, a through hole 104 is formed in the metal plate 101,
After that, the entire surface of this metal plate 101, including the inside of the through hole 104, is covered with an insulating layer 102 made of an insulating resin such as epoxy resin.
A through hole 105 covered with this insulating layer 102 is formed, and a through hole 105 is formed between the conductive circuits 103a and 103b laminated on both the front and back surfaces, respectively, with the insulating layer 102 interposed therebetween.
A wiring board called a metal core board, which is connected through a conductive portion 106 formed therein, has been proposed.

Since the wiring board using such a metal plate 101 as a base material has excellent strength and plastic workability, it can be bent or drawn into a predetermined shape required by electronic equipment. This has the advantage of increasing the degree of freedom in forming the substrate storage space provided in the electronic device.

However, even in a wiring board using such a metal plate 101 as a base material, the insulating layer 102 located at the corners is easily damaged during plastic processing or during use.
2 is damaged, the insulation reliability decreases, and in the case of a metal core substrate, it is necessary to completely cover the inside of the through hole 104 with insulation 1iJ102 without voids, which requires a lot of effort. was there.

For this reason, even with such metal-based substrates and metal-core substrates, plastic processing is usually limited to non-wiring areas, and it is difficult to create multiple layers for high density. It cannot be said that this is still sufficient to promote miniaturization, thinning, and weight reduction of equipment.

[Problems to be Solved by the Invention] This invention has been devised in view of the above points, and its purpose is to provide lightweight and excellent insulation reliability, and to provide a material that can be formed by bending, drawing, or other means. It is an object of the present invention to provide a wiring board that can be plastically processed to fit the shape of a board storage space required by various electronic devices, and a method for manufacturing the same.

Another object of the present invention is to be lightweight and have excellent insulation reliability, and to have a curved portion formed by plastic processing by means such as bending or drawing, and to have a shape that matches the shape of a board storage space of an electronic device. An object of the present invention is to provide a wiring board having the following features and a method for manufacturing the same.

[Means for Solving the Problem] That is, the present invention includes a sheet-like insulating base material formed of a hydrophilic polymer that absorbs water, becomes plasticized, and dries to harden; A plastically processable wiring board comprising an insulating resin layer that is cured during crimping under heat and pressure, and a metal conductive circuit that is fixed to the insulating base material through the insulating resin layer and etched into a predetermined pattern. ,
It is also a wiring board that has been plastically worked and has a predetermined curved portion, and roughly speaking, it is a method for manufacturing such a wiring board.

The present invention also provides a sheet-like insulating base material made of a hydrophilic polymer that absorbs water, plasticizes, dries, and hardens; An insulating resin layer, a plurality of metal conductive circuits located between and on the top surface of each of these insulating resin layers and etched in a predetermined pattern, and penetrating the insulating resin layer at a predetermined position between each conductive circuit. It is a multilayer wiring board that can be plastically processed and has a conductive part that electrically connects each of these conductive circuits, and it is also a multilayer wiring board that is plastically processed and has a predetermined curved part. This is a method for manufacturing a multilayer wiring board.

The sheet-shaped insulating base material used in the present invention absorbs water when immersed in water, softens the absorbed water as a plasticizer, and exhibits plasticity suitable for plastic processing such as bending and drawing. It also hardens again after plastic processing and dries, and has the property of maintaining a predetermined shape.Specifically, natural cellulose-based materials such as vulcanized fiber and presspod, and aramid fibers are used. Examples include crystalline polymer-based materials such as aromatic polyamide nonwoven fabrics called paper.

In addition, as for the insulating resin layer laminated on the surface of this insulating base material, when the wiring board has one layer of conductive circuit, this conductive circuit can be fixed to the insulating base material, and it can be used during plastic processing. It may be a thermoplastic resin or a thermosetting resin as long as it satisfies the heating temperature and heat resistance temperature required by electronic equipment, such as epoxy resin, diallyl phthalate resin, polyimide, etc. Examples of such resins include polyamide-based resins, polyamide-imide resins, melamine resins, urea resins, etc., but from the viewpoint of protecting the conductive circuit from stretching or breaking during plastic processing, it is preferable to use materials such as aramid paper or glass non-woven fabric. A flexible sheet is impregnated with a thermosetting resin, more preferably a diallyl phthalate resin showing a stable semi-cured state such as diallyl terephthalate, diallyl isophthalate, diallyl orthophthalate, etc., and an insulating base material and a conductive metal layer are impregnated. This thermoplastic resin is cured during crimping under heating ha pressure by sandwiching it between
It is better to be able to

In addition, if this wiring board is a multilayer wiring board having multiple conductive circuits, it is necessary to reliably insulate the conductive circuits in each layer. Since it is necessary to protect the paper and cuts, it is preferable to apply a thermosetting resin to a flexible sheet such as aramid paper or glass nonwoven fabric, and more preferably a stable semiconducting material such as diallyl terephthalate, diallyl isophthalate, diallyl orthophthalate, etc. It is preferable to use a thermoplastic resin impregnated with a hardened diallyl phthalate resin and then sandwiched between an insulating base material and a conductive metal layer and hardening this thermoplastic resin during compression bonding under heat and pressure.

Further, for the conductive circuits etched into a predetermined pattern, metals commonly used in this type of wiring board, such as copper, nickel, aluminum, etc., are used.

When the wiring board is a multilayer wiring board, conductive parts are formed at predetermined positions between each conductive circuit, and these conductive parts can electrically connect adjacent conductive circuits. Although it is not particularly limited, it is preferable that it penetrates the upper conductive circuit and the insulating resin layer disposed on the lower side thereof in order to ensure the reliability of the electrical connection. A through hole is provided, and copper,
It has a structure in which it is filled with a conductive paste such as silver or carbon or a conductive substance such as solder, thereby electrically connecting an upper conductive circuit and a lower conductive circuit.

The wiring board or multilayer wiring board of the present invention can be made into a product in a flat state before being formed into a desired shape by plastic processing such as bending or drawing, or can be further processed by bending or drawing. Through plastic working, it is possible to form a product into a shape required by the substrate storage space of an electronic device, thereby making it possible to produce a product having a curved portion.

Next, a method for manufacturing the wiring board and multilayer wiring board of the present invention will be explained.

First, the manufacturing method of a wiring board having only one layer of conductive circuit basically involves providing an insulating resin layer on the surface of the above-mentioned sheet-like insulating base material and providing a conductive metal layer on the insulating resin layer. , the obtained laminate is bonded and integrated under heat and pressure, the conductive metal layer is etched in a predetermined pattern to form a conductive circuit, and the insulating base material is made to contain water to make it plastic. It consists of the steps of forming into a predetermined shape by processing and drying.

In addition, regarding the manufacturing method of a multilayer wiring board in which multiple conductive circuits are laminated, basically, a conductive metal layer is laminated on a semi-cured insulating resin layer that exhibits a stable semi-cured state, and the resulting laminate is A step of etching a predetermined pattern on the conductive metal layer to produce a laminate having the semi-cured insulating resin layer and a conductive circuit; A process of forming a multilayer laminate by sequentially laminating the conductive circuits on the surface of the primary laminate with their conductive circuits facing upward, pressing them together under heat and pressure, and curing the semi-hardened insulating resin layer of the primary laminate; In the manufacturing process, a process of forming a conductive part that electrically connects the upper conductive circuit and the lower conductive circuit, and a process of plasticizing the insulating base material by impregnating it with water and plasticizing it into a predetermined shape. It consists of

Hereinafter, methods for manufacturing these wiring boards and multilayer wiring boards will be explained in detail with reference to the accompanying drawings.

First, FIG. 1 shows an example of manufacturing a wiring board having only one layer of conductive circuit, in which an insulating resin layer 2 is provided on the surface of a sheet-like insulating base material 1, and conductive circuits are formed through this insulating resin layer 2. A metal layer 3 is provided, and the resulting laminate is bonded under heat and pressure to be integrated (see FIGS. 1(a) and 1(b)).

As shown in an enlarged view in FIG. 2, the heating and pressing conditions during this crimping are such that a part of the resin used impregnates the surface of the insulating base material 1 to form a resin-impregnated layer A, which is the so-called anchor effect. Although it varies depending on the type, thickness, and combination of resins used for the insulating base material 1 and the insulating resin layer 2, the heat resistance temperature of the insulating base material 1 is not exceeded and the insulating resin layer 2 It is sufficient if the temperature is such that the resin used can be compressed. Moreover, the pressure may be such that the insulating base material 1 and the insulating resin layer 2 are brought into close contact with each other and no air bubbles remain. For example, when using a thermosetting resin as the insulating resin M2, the temperature is 120~
170℃, pressure 5-70'j/cM-G and time 30
~60 minutes is best. The insulating resin layer 2 may be first laminated on the insulating base material 1 and then the conductive metal layer 3 may be laminated on the insulating resin layer 2. This may be laminated on the insulating base material 1 after being laminated, and if a thermosetting resin is used as the resin constituting the insulating resin layer 2, it is hardened during the compression bonding under heat and pressure.

In the thus formed laminate, the conductive metal layer 2 is then etched into a predetermined pattern to form a conductive circuit 4, and the necessary through holes 5 used for mounting electronic components etc. are roughly formed. (See Figure 1(C)). This etching process may be carried out by a conventionally known method. For example, the surface of the conductive metal layer 3 is degreased, then a circuit pattern is screen printed with an etching resist made of alkali-soluble acid-resistant ink, dried, and then etched with dichloromethane. Etched with iron solution,
Furthermore, after removing the resist with an alkaline solution such as sodium hydroxide, it is neutralized with an acidic solution such as sulfuric acid, washed with water, and dried at room temperature.

In the thus formed laminate in which the conductive circuits 4 are laminated, the insulating base material 1 is then impregnated with water to be plasticized. This can be done by spraying water or exposing it to high humidity for a certain period of time, but it is preferable to do so as shown in Figure 1 (
As shown in d), it is preferable to fill a water tank 6 with water 7 and immerse it in this water 7 for a certain period of time. The conditions at this time vary depending on the material, thickness, etc. of this insulating base material 1, but for example, in the case of natural cellulose-based vulcanized fibers, it takes about 10 to 40 minutes at room temperature, and for aromatic polyamide-based vulcanized fibers, In the case of laminated paper, it is sufficient to soak it at room temperature for about 6 to 24 hours, and the moisture content of the insulating base material 1 at this time is usually about 15 to 35% by weight, preferably about 20 to 30% by weight.

At this level of water content, the material's elongation at break nearly doubles, making it a tough and flexible material.

After the insulating base material 1 is plasticized in this way, it is then formed into a predetermined shape by plastic processing such as bending or drawing, and dried to form a final product having a predetermined curved portion 8 (see Fig. 1). (see (e)). The conditions for this plastic working can be appropriately selected depending on the material and thickness of the insulating base material 1, the type and thickness of the resin constituting the insulating resin layer 2, etc. , the heating temperature can be selected in the range of room temperature to about 150°C, preferably at a temperature exceeding the boiling point of water, for example, about 100 to 130°C, and the time for water to volatilize;
For example, about 2 to 3 hours is good, and if the plastic working is simultaneously heated and dried and hardened, the return of the curved portion 8 can be prevented as much as possible.

Next, FIG. 3 shows a first example in which the wiring board is a multilayer wiring board having a plurality of conductive circuits.

That is, first, a conductive metal layer 13 is laminated on a semi-cured insulating resin layer 12a obtained by impregnating a flexible sheet such as aramid paper with a semi-cured resin exhibiting a stable semi-cured state such as a diallyl phthalate resin. Then, a predetermined pattern is etched on the conductive metal layer 13 of the obtained laminate to form a conductive circuit 14.
A laminate 15a having a shape is produced. Etching at this time can be performed according to the conventional method as described above.

The thus obtained laminate 15a is laminated on the surface of a sheet-like insulating base material 11 such as vulcanized fiber with the conductive circuit 14a facing upward, and the obtained laminate is crimped under heat and pressure. Semi-hardened insulating resin layer 1 of laminate 15a
2a is cured to form a laminate 16 having a first conductive circuit 14a on the upper surface. The crimping conditions under heat and pressure at this time can also be carried out under the same conditions as above.

Next, a laminate 15b having a second conductive circuit 14b having the same or different pattern as the conductive circuit 14a on the surface is produced in the same manner as above, and this laminate 15b has the laminate 1
A through hole 17a used for electrical connection with the conductive circuit 14a of 5a and a through hole 18 necessary for the purpose of mounting electronic components, etc.
Drill a. Then, this laminate 15b is laminated on the upper surface of the laminate 16, and the laminate 19 having the conductive circuit 14b on the upper surface is formed in the same manner as that used to produce the laminate 16.

In method 1 shown in FIG. 3, the third conductive circuit 14c is provided on the surface as described above, and the through hole 17b,
18b and 18c are formed, and this is laminated on the laminate 19 in the same manner as above to form the final laminate 20 having the conductive circuit 14C on the upper surface, and then the conductive circuit 14b is formed. The through holes 17a of the laminate 15b having the conductive circuits 14C and the through holes 17b of the laminate 15c having the conductive circuits 14C are filled with a conductive substance, and if necessary, the conductive substances are heated and hardened to form these conductive circuits 14a and 1.
4b and 14c are formed, and a through hole 22 for mounting an electronic component is formed to penetrate through the secondary laminate 16 via the through holes 18a and 18c. There is.

Here, the semi-cured insulating resin layers 12a, 12b, and 12c of each of the laminates isa, i5b, and 15C are cured in the crimping process under heat and pressure in the manufacturing process of this multilayer wiring board to form the insulating resin layer (Fig. 4). , the same reference numerals 12a, 12b and 12c as above are attached), but in this case, the stacked bodies 15b and 15C located above
Part of each of the semi-cured insulating resin layers 12b and 12C melts and enters the non-conductive space of each of the conductive circuits 14a and 14b of the laminates 15a and 15t located below and hardens. Conductive circuits 14a and 14b are protected.

Note that the process of forming the conductive parts 21a and 21b from the laminate 19 through the final laminate 20 is not limited to the procedure shown in FIG. A conductive portion 21a that electrically connects between the two conductive circuits 14a and 14b is formed, and then a laminate 15C is laminated to form a final laminate 20, and each of the layers formed in this final laminate 20 is then A conductive portion 21b may be formed to electrically connect the conductive circuits 14b and 14c. In addition, although this FIG. 3 explains the case of manufacturing a multilayer wiring board having three layers of conductive circuits, the process of sequentially laminating each laminate and forming a conductive part is repeated an appropriate number of times to provide conductivity. A multilayer wiring board in which a predetermined number of circuits are laminated can be manufactured.

The final laminate 20 thus formed is then plasticized by impregnating the insulating base material 11 with water in the same manner as above, and then roughly bent and drawn in the same manner as above. It is subjected to plastic processing such as molding to form a predetermined curved portion 23 as shown in FIG. 4, and finally dried in the same manner as above to form a final product, a multilayer wiring board.

Briefly, FIG. 5 shows a second example in which the wiring board is a multilayer wiring board.

In the case of this FIG. 5, the conductive metal layer 13 is laminated on each of the semi-cured insulating resin layers 12a, 12b and 12C which are in a stable semi-cured state, and the conductive metal layer 13 of each of the obtained laminates is A predetermined pattern is etched to form a conductive circuit 1.
Laminated bodies 15a, 15 having 4a, 14b and 14c
b and 15c, and further the above laminates 15b and 1
Regarding 5C, through holes 17a, 117b, which are used for electrically connecting between upper and lower conductive circuits, or for mounting electronic components, etc., are provided at predetermined positions.
18a, 118b, and 118c;
a, 14b, and 14C are stacked one after another with the sides facing upward, and are bonded under heat and pressure to form each laminate 15a, 15b, and 15c.
The semi-cured insulating resin layers 12a, 12b and 12C are cured to form the cured insulating resin layers 12a, 12b and 12.
a step of integrating each of the laminates 15a, 115b and 15c by c, and each of the integrated laminates 15a, 15;
A step of fixing the sheet-like insulating base material 11 to the lower surface side of b and 15C via the adhesive layer 24 to form the final laminate 20, and forming each through hole 17a in the final laminate 20.
and 17b are filled with a conductive substance to form an upper conductive circuit 14b.
and 4C and conductive circuits 14a and 14 located below it.
a step of forming conductive portions 21a and 21b for electrically connecting between The final laminate 20 thus obtained is made to contain water in the insulating base material 11 to be plasticized, and is then subjected to plastic working such as bending and drawing in the same manner as described above.

In manufacturing the wiring board or multilayer wiring board as described above, during plastic processing performed after the insulating base material 11 is hydrated and plasticized, for example, as shown in FIG. 6 (aHb),
A V-shaped cut 25 is made in the insulating base material 11 in advance,
This makes it possible to reduce stress generation during plastic working as much as possible, and to form a curved portion 23 with a relatively acute angle.

[Function] According to the present invention, the sheet-like insulating base material used as the base material of the wiring board is made of a hydrophilic polymer that absorbs water, becomes plasticized, and dries to harden. In addition to being able to perform plastic processing such as bending and drawing in the same way as when using a plate as a base material, there is extremely little stress concentration at the curved parts that are formed, and the insulating base material and conductive circuit can be easily connected during manufacturing. The insulating resin layer interposed between the parts partially impregnates the surface of the insulating base material and exerts a so-called anchor effect, so there is no possibility that the conductive circuit will peel off from the insulating base material during this plastic processing. Moreover, unlike the case where the base material is a metal plate, since the base material is an insulating material, it is extremely easy to form holes such as through holes for mounting electronic components.

[Example] Hereinafter, the wiring board of the present invention and its manufacturing method will be specifically described based on Examples.

Example 1 A laminate of a 35 m thick copper foil and a 65 m thick semi-hardened insulating resin sheet made by impregnating a non-woven fabric of aromatic polyamide fiber with a diallyl phthalate resin composition (product name: Amiflex manufactured by Daiso). , product number P-96B>, and after degreasing the copper foil with Freon, apply an alkali-soluble acid-resistant ink (manufactured by Taiyo Ink Manufacturing ■, product number X-77>) on the copper foil.
After screen printing the circuit pattern shown in Figure 7 using After neutralizing with a .61 wt % sulfuric acid solution, it was washed with water and dried under reduced pressure to produce 10 laminates of conductive circuits and semi-cured insulating resin sheets. In this state, the average conduction resistance at four points of the conductive circuit formed on each laminate was measured and found to be 0.491Ω.

Next, this laminate was placed with its conductive circuit facing up, and a vulcanized fiber (Hokuetsu Paper Co., Ltd. (11) ¥A product name 2FR-781
＞, 160℃, 70Kfj/cat・G
The semi-cured resin of the semi-cured insulating resin sheet is cured and laminated by heating and pressing at roughly 120°C, 70'J/cm-G and 60 minutes. The body was integrally fixed to the vulcanized fibers, and then Komei processed the body into its predetermined positions.

The final laminate obtained in this way was immersed in water in a water tank, and then immersed at room temperature for 30 minutes to make the vulcanized fibers absorb water. The average weight before adding water is 8.2g, the average weight after adding water is 10.49, and the water content is 1
The range was 4% to 26%.

Next, with respect to the final laminate treated with water in this way, half of the five sheets had the conductive circuit on the inside, and the other half had the conductive circuit on the outside, and each was bent along the line A-A in Figure 7. While maintaining the bent shape with a radius of 7 m, the temperature was 100°C, 2
Bending forming and drying were performed under the condition of time.

For each wiring board obtained, the average conduction resistance was measured at four points in the conductive circuit, and the change was less than 1% at most, and the conductive circuit was normal with no break points observed.

Example 2 A laminate in which a conductive circuit having the first layer pattern shown in FIG. It was superimposed on a 0.51 m nonwoven fabric of aromatic polyamide fiber (trade name: Nomex, product number 410, manufactured by DuPont Japan Limited), and crimped under heat and pressure at 160° C., 70 KI/ci-G, and 60 minutes, The semi-cured resin of the semi-cured insulating resin sheet was cured, and the laminate was integrally fixed to the nonwoven fabric of aromatic polyamide fibers.

Next, holes are drilled and the same procedure as shown in Fig. 8 (
A laminate in which the conductive circuit of the second layer pattern shown in b) and the semi-hardened insulating resin sheet are laminated is produced, and this 2H laminate is used as the first layer to which the nonwoven fabric of aromatic polyamide fiber is fixed. Superimposed on the eye laminate, 160°C, 30KI
/ci-G and 30 minutes of heat and pressure to harden the semi-cured insulating resin sheet of the second layer laminate, and at the same time, the upper and lower two-layer laminate is integrally bonded to the nonwoven fabric of aromatic polyamide fibers. A final laminate was made that was adhered to.

Conductive paste (product name: E-1000 manufactured by Mitsui Kinzoku ■) is filled into the through holes formed in the upper layer laminate of this final laminate by screen printing, and cured at 160°C for 30 minutes. A conductive portion was formed to connect the conductive circuit of the body and the conductive circuit of the lower layer laminate. In this state, the conduction resistance was measured at two points in each conductive circuit, and the average conduction resistance was 0.650.

This final laminate was further immersed in water for 24 hours in the same manner as in Example 1 above to impregnate the nonwoven fabric of aromatic polyamide fibers with water. The average weight before adding water was 8.1 g, and the average weight after adding water was 9°629, and the water content ranged from 15 to 24%.

Next, regarding the final laminate treated with moisture in this manner, half of the five sheets had the conductive circuit on the inside, and the other half had the conductive circuit on the outside, as shown in Figures 8(a) and (b).
Bending and drying were performed at 100° C. for 2 hours while maintaining the bent shape at a bending radius of 7 m along the line B-B.

As a result of measuring the average conduction resistance at two points of the conductive circuit for each wiring board obtained, the results were as follows in Example 1 above.
Similarly, the change was less than 1% at most, and no break points were observed in the conductive circuit, which was normal.

[Effects of the Invention] The wiring board of the present invention is lightweight and has excellent insulation reliability, and can be plastically worked by means such as bending or drawing to match the shape of the board storage space required by various electronic devices. In addition, it can be plastically worked by bending or drawing to have a curved part, which can be shaped to match the shape of the board storage space of electronic devices, making electronic devices smaller and lighter. This can be adapted to the demands for thinning and thinning. Also,
According to the method of the present invention, such a wiring board can be easily manufactured.

[Brief explanation of the drawing]

1(a) to (e) are cross-sectional explanatory diagrams showing a method for manufacturing a wiring board according to the present invention, FIG. 2 is a partially enlarged cross-sectional explanatory diagram of a wiring board obtained by the method of FIG. 3 is an explanatory cross-sectional view showing a method for manufacturing a multilayer wiring board according to the present invention, FIG. 4 is an explanatory partially enlarged cross-sectional view of a multilayer wiring board obtained by the method shown in FIG. 3, and FIG. FIG. 6 is a cross-sectional explanatory diagram showing another method of manufacturing such a multilayer wiring board. FIG. 6 is a cross-sectional explanatory diagram showing an example of bending. FIG. FIGS. 8(a) and 8(b) are explanatory diagrams showing the conductive circuit patterns of the upper and lower layers adopted in the wiring board of Example 2, and FIGS. 9 and 10 are the conventional circuits using metal plates. FIG. 2 is an explanatory cross-sectional view showing the wiring board of FIG. Explanation of symbols 1 (11)... Insulating base material, 2... Insulating resin layer, 3 (13)... Conductive metal layer, 4... Conductive circuit, 5... Through hole, 6... - Water tank, 7...Water, 8 (23)...Curved portion, 12a) (12b) (12c)--Semi-cured insulating resin layer (insulating resin layer), (14aH14b) (14c)-- Conductive circuit, (1
5a) (15b) (15c) (16) (19) (20)
...Laminated body, (17a) (17b) (18a) (1
8b) (18c) -...Through hole, (21a) (21b
)--Conducting portion, (22)...Through hole for mounting electronic components, (24)...Adhesive layer, (25)...Notch.

Claims (10)

[Claims] (1) A sheet-like insulating base material made of a hydrophilic polymer that absorbs water, plasticizes, dries and hardens; an insulating resin layer laminated on the surface of this insulating base material; A plastically processable wiring board, characterized in that it has a metal conductive circuit fixed to the insulating base material and etched in a predetermined pattern. (2) The wiring board according to claim 1, which is plastically worked and has a predetermined curved portion. (3) The wiring board according to claim 1 or 2, wherein the insulating resin layer comprises a flexible sheet and an insulating resin that is impregnated into the flexible sheet in a semi-cured state and is cured upon pressure bonding. (4) providing an insulating resin layer on the surface of a sheet-like insulating base material made of a hydrophilic polymer that absorbs water, plasticizes, dries and hardens; and providing a conductive metal layer on the insulating resin layer;
The obtained laminate is bonded and integrated under heat and pressure, the conductive metal layer is etched into a predetermined pattern to form a conductive circuit, and then the insulating base material is made to contain water and plasticized, and is then processed by plastic processing. A method of manufacturing a wiring board, which is characterized by forming it into a predetermined shape and drying it. (5) A semi-cured insulating resin layer is formed by impregnating a flexible sheet with a semi-cured insulating resin that exhibits a stable semi-cured state, and this semi-cured insulating resin layer is cured during crimping under heat and pressure. 5. The method of manufacturing a wiring board according to claim 4, wherein the wiring board is formed into a layer. (6) A sheet-like insulating base material made of a hydrophilic polymer that absorbs water, plasticizes, dries and hardens, and multiple insulating resin layers that are laminated on the surface of this insulating base material and harden when crimped under heat and pressure. , a plurality of metal conductive circuits located between and on the top surface of each of these insulating resin layers and etched in a predetermined pattern, and a plurality of metal conductive circuits that penetrate the insulating resin layer at a predetermined position between each of the conductive circuits A plastically processable multilayer wiring board characterized by having a conductive part that electrically connects circuits. (7) The multilayer wiring board according to claim 6, which is plastically worked and has a predetermined curved portion. (8) The multilayer wiring board according to claim 6 or 7, wherein the insulating resin layer comprises a flexible sheet and a diallyl phthalate resin that is impregnated into the flexible sheet in a semi-hardened state and hardened upon pressure bonding. (9) A conductive metal layer is laminated on the semi-cured insulating resin layer that exhibits a stable semi-cured state, and a predetermined pattern is etched on the conductive metal layer of the obtained laminate, so that it is conductive with the semi-cured insulating resin layer. A step of manufacturing a laminate having a circuit, and sequentially laminating a plurality of laminates thus manufactured on the surface of a sheet-like insulating base material with their conductive circuits facing upward, and pressing them together under heat and pressure. In addition, in the process of curing the semi-cured insulating resin layer of the primary laminate to form a multilayer laminate, and in the process of manufacturing this multilayer laminate, electrical connection between the upper conductive circuit and the lower conductive circuit is performed. 1. A method for manufacturing a multilayer wiring board, comprising the steps of: forming a conductive portion connected to the insulating base material; and plasticizing the insulating base material by impregnating it with water, and plasticizing it into a predetermined shape. (10) The method for manufacturing a multilayer wiring board according to claim 9 or 10, wherein the semi-cured insulating resin layer is formed by impregnating a flexible sheet with a diallyl phthalate resin that exhibits a stable semi-cured state.