JPH08204311A - Manufacture of printed wiring board - Google Patents

Abstract

PURPOSE: To provide a printed wiring board manufacturing method by which selected ones of a plurality of wall surfaces nearly perpendicular to a planar exposure mask positioned against an insulating substrate composed of a three- dimensional molded body exist on the three-dimensional surface of the insulating substrate. CONSTITUTION: In a printed wiring board manufacturing method, a printed wiring board having through holes 7 for forming a printed wiring circuit 2p and a plurality of wall surfaces nearly perpendicular to a plane mask for exposure by forming a resist 3a by irradiating an electrodeposited resist 3 with light through the mask 4 after successively forming a conductive layer 2 and the resist 3 on the surface of a three-dimensional molded body 1 having an insulating property. The method includes a parallel light ray irradiating process in which a prescribed part of the resist 3 is irradiated with parallel light rays 5h and scattered light irradiating process in which the resist 3 formed on prescribed wall surfaces nearly perpendicular to the mask 4 with scatter light 5s through the mask 4.

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 three-dimensional printed wiring board.

[0002]

2. Description of the Related Art Conventionally, circuit formation in a method of manufacturing a printed wiring board using a three-dimensional molded product as an insulating substrate is disclosed in, for example, Japanese Patent Laid-Open No. 4-76985. That is, as shown in FIGS. 4 (a) to 4 (c), after roughening the surface of the three-dimensional molded article 10 to an appropriate surface roughness, the entire surface for circuit conductors is subjected to electroless plating or electrolytic plating. A conductive layer 20 of copper or the like is formed. Next, a film such as an electrodeposition resist 30 having photosensitivity is formed on the surface of the conductive layer 20, and exposed by parallel light 50 through the exposure flat mask 40,
After developing to form a resist 30a such as an etching resist, the exposed conductive layer 20 is etched to form a printed wiring circuit 20p on the three-dimensional surface of a three-dimensional insulating substrate as shown in FIG. 3A. Has been used. Here, the electrodeposition resist 30 has a photosensitivity that cures or dissolves when exposed to light, and the unnecessary electrodeposition resist 30 is removed in the developing process to remove the unnecessary conductive layer 2.
When 0 is exposed, the unnecessary conductive layer 20 is dissolved by the etching solution, and the conductive layer 20 necessary for the circuit pattern is covered with and protected by the resist 30a such as an etching resist and therefore is not dissolved by the etching solution. Remain. Therefore,
After the etching is completed, the printed wiring circuit 20p is formed on the three-dimensional surface of the three-dimensional molded product 10 from the conductive layer 20 by peeling the resist 30a such as the used etching resist with a peeling liquid. When the positive type (photo-dissolving type) electrodeposition resist 30 is used, the electrodeposition resist 30 is decomposed only in the exposed portion and the underlying conductive layer 2 is used.
0 is exposed. That is, the electrodeposition resist 3 in the unexposed area
0 remains as it is and resist 3 such as etching resist
It becomes 0a and becomes a circuit pattern. On the contrary, when a negative type (photo-curing type) electrodeposition resist is used, the resist is hardened only in the exposed part, and the resist in the unexposed part is dissolved by the development. That is, the electrodeposition resist 30 in the exposed portion remains as it is and becomes a circuit pattern.

However, in the method as described above, FIG.
It was not possible to obtain a printed wiring board as shown in (b), FIG. 3 (e) and FIG. 3 (f). That is, when there are a plurality of substantially vertical wall surfaces 10s of the three-dimensional molded product 10, a predetermined substantially vertical wall surface 10 among these substantially vertical wall surfaces 10s.
s cannot be selectively exposed, and the wall surface 10 is substantially vertical.
Either the conductive layer 20 is formed on all s, or the conductive layer 20 is not formed on any of the substantially vertical wall surfaces 10s. Japanese Unexamined Patent Publication No. 4-76985
In the embodiment disclosed in the publication, a positive type electrodeposition resist 30 is used. That is, as shown in FIGS. 4A and 4B, when the positive electrodeposition resist 30 is used, light is transmitted through the exposed portion 40a which is a transparent portion of the exposure flat mask 40. However, the exposure plane mask 4
In order to irradiate the parallel light 50 parallel to the virtual vertical line 40s for 0, the positive electrodeposition resist 30 formed on the substantially vertical wall surface 10s is not exposed. Therefore, as shown in FIG. The resist 30a such as an etching resist remains on the substantially entire surface of the vertical wall surface 10s, and patterning cannot be performed. Therefore, as shown in FIG. 3C, the conductive layer 20 is formed on all substantially vertical wall surfaces 10s. When the unnecessary conductive layer 20 is formed on the substantially vertical wall surface 10s of the three-dimensional molded product 10, for example, the sealing resin and the circuit metal are poorly adhered to each other in the mounting and sealing in the subsequent step, so that the sealing resin and the circuit are not formed. There is a problem that moisture enters from the interface with the metal and the reliability deteriorates.

Therefore, conventionally, as shown in FIG. 3A, for example, a three-dimensional molded product 10 which does not require formation of the conductive layer 20 is used.
By forming the inclined surface 10k at a certain angle without making the wall surface vertical, the conductive layer 20 is not formed on the inclined surface 10k, and the conductive layer 20 is formed on the substantially vertical wall surface 10s of the through hole 70. Therefore, there is a problem that the substrate becomes large. Further, in order to reduce the size, as shown in FIG. 3 (f), the circuit is insulated by the substantially vertical wall surface 10s. However, even if it is desired to insulate the circuit with the substantially vertical wall surface 10s, if there is the substantially vertical wall surface 10s of the through hole 70 such as the through hole in which the conductive layer 20 has to be formed, a plurality of wall surfaces 10s are formed as described above. Almost vertical wall surface 10s
Therefore, it was not possible to selectively expose the predetermined substantially vertical wall surface 10s.

On the contrary, even when the negative electrodeposition resist 30 is used, the electrodeposition resist 30 is cured only in the exposed portion, and the unexposed portion of the electrodeposition resist 30 is dissolved by the development. That is, as shown in FIGS. 5A and 5B, in order to irradiate the parallel light 50 in parallel with the virtual vertical line 40 s with respect to the exposure plane mask 40, the substantially vertical wall surface 10 s of the through hole 70 is irradiated. Since the formed negative electrodeposition resist 30 is not exposed, the resist 30a such as an etching resist is not formed on the substantially vertical wall surface 10s such as the through hole 70 as shown in FIG. 5C. Therefore, as shown in FIG. 3D, there is a problem that the conductive layer 20 is not formed on any of the substantially vertical wall surfaces 10s, and the printed wiring circuit cannot be formed (patterned) on a predetermined surface. In the above description, when there are a plurality of substantially vertical wall surfaces 10s of the printed wiring board, that is, the three-dimensional molded product 10 as shown in FIGS. A predetermined substantially vertical wall surface 10s cannot be selectively exposed out of the substantially vertical wall surface 10s, and the conductive layer 20 is formed on all of the substantially vertical wall surface 10s, or the substantially vertical wall surface 10s. 1
This is a common problem in that the conductive layer 20 is not formed on any of the 0s.
In the case of a printed wiring board as shown in (b), that is, when the through hole 70 has a step portion and one through hole 70 has a plurality of substantially vertical wall surfaces 10s, these substantially vertical wall surfaces 1
It was more difficult to selectively expose a predetermined substantially vertical wall surface 10s within 0 s.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above facts, and an object of the present invention is to provide a three-dimensional surface of an insulating substrate composed of a three-dimensional molded product, which is disposed on the three-dimensional molded product. When there are a plurality of substantially vertical wall surfaces with respect to the exposed exposure plane mask, a method of manufacturing a printed wiring board capable of reliably performing exposure on a predetermined substantially vertical wall surface from these substantially vertical wall surfaces To provide.

[0007]

A method for manufacturing a printed wiring board according to claim 1 of the present invention comprises forming a conductive layer 2 on the surface of a three-dimensional molded article 1 having an insulating property and exposing the conductive layer 2 to light. Which forms the printed wiring circuit 2p by forming the electro-deposition resist 3 having the property and exposing the electro-deposition resist 3 by exposing it to light through the exposure flat mask 4 to form the resist 3a. A method for manufacturing a printed wiring board having holes 7 and having a plurality of substantially perpendicular wall surfaces 1s with respect to the exposure plane mask 4, comprising an exposed portion 4a and an unexposed portion 4b arranged in the three-dimensional molded article 1. The parallel light exposure step of irradiating the predetermined electrodeposition resist 3 by irradiating the parallel light 5h through the exposure plane mask 4 and the exposure by irradiating the scattered light 5s through the exposure plane mask 4 Plane mask 4
And a scattered light exposure step of exposing the electrodeposition resist 3 formed on a predetermined substantially vertical wall surface 1s.

In the method for manufacturing a printed wiring board according to claim 2 of the present invention, the through hole 7 has a step portion, and the diffused reflection plate is provided on the surface of the three-dimensional molded article 1 on the side of the small opening portion 7k of the through hole 7. 8
An exposure plane mask 4 is provided on the surface of the three-dimensional molded article 1 on the side of the large opening 7t of the through hole 7 to cover the small opening 7k. A parallel light exposure step of irradiating a predetermined electrodeposition resist 3 by irradiating light 5h, and a light absorbing plate 8k are provided on the surface of the three-dimensional molded article 1 on the side of the large opening 7t to cover the large opening 7t. An exposure plane mask 4 is provided on the surface of the three-dimensional molded article 1 on the side of the small opening 7k, and a predetermined electrodeposition resist 3 is exposed by irradiating scattered light 5s through the exposure plane mask 4. And a scattered light exposure step.

[0009]

In the method for manufacturing a printed wiring board according to the first aspect of the present invention, the three-dimensional molded article 1 is parallelized through the exposure flat mask 4 having the exposed portion 4a and the unexposed portion 4b. In the parallel light exposure step of irradiating the electrodeposition resist 3 by irradiating the light 5h, the wall surface 1s substantially perpendicular to the exposure plane mask 4 is exposed.
The predetermined electrodeposition resist 3 other than the electrodeposition resist 3 formed on the surface is accurately exposed, and a wall surface 1s substantially perpendicular to the exposure plane mask 4 that cannot be exposed in the parallel light exposure process.
In the case where there are a plurality of these, the electrodeposition resist 3 formed on the predetermined substantially vertical wall surface 1s is selectively irradiated from the substantially vertical wall surface 1s with the scattered light 5s through the exposure plane mask 4. Since the exposure is performed in the scattered light exposure step of exposing the electrodeposited resist film 3 to the predetermined vertical wall surface 1s, the electrodeposition resist 3 can be reliably exposed.

In the method for manufacturing a printed wiring board according to the second aspect of the present invention, the through hole 7 has a step portion, and the diffused reflection plate is provided on the surface of the three-dimensional molded article 1 on the side of the small opening portion 7k of the through hole 7. 8h is provided to cover the small opening 7k, the exposure plane mask 4 is provided on the surface of the three-dimensional molded article 1 on the side of the large opening 7t of the through hole 7, and the exposure plane mask 4 is used for parallelization. Since there is a parallel light exposure step of irradiating the predetermined electrodeposition resist 3 by irradiating the light 5h, the parallel light 5h hits the diffused light reflection plate 8h and is diffused to become the scattered light 5s. Thus, the predetermined electrodeposition resist 3 formed on the wall surface 1s perpendicular to the exposure plane mask 4 is exposed. Moreover, a light absorbing plate 8k is provided on the surface of the three-dimensional molded article 1 on the side of the large opening 7t to cover the large opening 7t, and a flat mask for exposure is formed on the surface of the three-dimensional molded article 1 on the side of the small opening 7k. 4 is provided, and since there is a scattered light exposure step of exposing the predetermined electrodeposition resist 3 by irradiating the scattered light 5s through the exposure plane mask 4, the irradiated scattered light 5s emits the scattered light 5s. In order to prevent the scattered light 5s from being radiated to the surface of the vertical wall surface 1s or the like which is absorbed by the above and does not need to be exposed, the electrodeposition formed on the surface of the vertical wall surface 1s or the like which is not exposed. The resist 3 is hard to be exposed. That is, the through hole 7 has a step,
Even when one through hole 7 has a plurality of substantially vertical wall surfaces 1s, a predetermined substantially vertical wall surface 1s can be selectively exposed among these substantially vertical wall surfaces 1s.

[0011]

EXAMPLES The present invention will be specifically described below with reference to examples.

FIG. 1 shows a first embodiment. As shown in FIG. 1A, a three-dimensional molded article 1 having a concavo-convex shape provided with through-holes 7 such as through-holes serving as a three-dimensional insulating substrate of a printed wiring board is formed of, for example, thermosetting resin or It is obtained by molding by injection molding or the like using a thermoplastic resin or the like. For example, injection molding is performed using a super engineering plastic such as liquid crystal polymer (manufactured by Polyplastics Co .: trade name Vectra). Of course, the present invention is not limited to injection molding, and the three-dimensional molded article 1 having the through holes 7 may be finished by cutting. After roughening the three-dimensional surface of the three-dimensional molded article 1 with a strong alkaline solution to a suitable surface roughness and then nucleating palladium to facilitate adhesion of the conductive layer 2, for example, electroless copper Plating, sputtering, vapor deposition, or the like is performed on the entire surface of the three-dimensional molded article 1, and a required thickness is formed on the surface by electrolytic copper plating to form a conductive layer 2 for a circuit conductor on the entire surface. Next, an electro-deposition resist 3 having photosensitivity, for example, a photo-curing (negative) or photo-dissolution (positive) electro-deposition resist 3 is formed on the surface of the conductive layer 2.

The reason why the electrodeposition resist 3 is preferable as the resist having photosensitivity is that, when a general liquid resist is formed on the uneven three-dimensional surface of the three-dimensional molded article 1, the followability to the unevenness is 10 μm. Although the accuracy of circuit formation is poor, the electrodeposition resist 3 can perfectly follow and adhere to the uneven three-dimensional surface of the three-dimensional molded product 1, and the accuracy of circuit formation is improved. Is. Here, the photocurable electrodeposition resist 3 is cured when exposed to light (exposed), and the photodissolving electrodeposition resist 3 is dissolved when exposed to light. Therefore, for example, a photo-curable (negative) electrodeposition resist (manufactured by Shipley Co., Ltd .: trade name Eagle) is formed on the surface of the conductive layer 2 by electrophoresis, and then, for example, as shown in FIG.
As shown in (b), exposure of a parallel exposure machine 6h or the like is performed in parallel with the virtual vertical line 4s for the exposure plane mask 4 provided with the exposed portion 4a and the unexposed portion 4b arranged in the three-dimensional molded article 1. The apparatus is used to perform exposure with parallel light 5h such as ultraviolet rays through the exposure plane mask 4. In FIG. 1B, the parallel exposure device 6h is schematically shown by the light source 6k and the lens 6r. The parallel light 5h can be obtained, for example, by placing the light source 6k at the focal point of the lens 6r or the like and passing it through the lens 6r. That is, the collimated light 5h is, for example, the exposure area of the shield plate when the shield plate is used to shield the light at a certain position and the exposure area of the shield plate when the shield plate is shielded at a different position. The light is the same. Therefore, the exposure accuracy is good when the parallel light 5h is used.

However, the wall surface 1s perpendicular to the irradiation direction of the parallel light 5h is hardly exposed when the parallel light 5h is used. That is, the predetermined electrodeposition resist 3 formed on the vertical wall surface 1s cannot be exposed only by the parallel light 5h. Therefore, as shown in FIG. 1 (c), after the exposure using the parallel light 5h or before the exposure, for example,
The exposure plane mask 4 is formed by using a predetermined exposure plane mask 4 in which the exposure portion 4a is brought into contact with the through hole 7.
Through the exposure flat mask 4, an exposure device such as a scattering exposure device 6s is used to perform exposure with light of scattered light 5s such as ultraviolet light. It is difficult to expose the electrodeposition resist 3 formed on the vertical wall surface 1s such as the through hole 7 with the parallel light 5h, but by using the scattered light 5s, the electrodeposition resist 3 formed on the vertical wall surface 1s is exposed. 3 can be easily exposed. That is, for example, the scattered light 5s is different in the exposure area of the shielding plate when the shielding plate is used to block the light at a certain position and the exposure area of the shielding plate when the shielding plate is used to change the position. . That is, the scattered light 5s is such light that the exposure area increases as the distance between the light source of the scattered light 5s and the shield plate increases. Therefore, when the scattered light 5s is used, the wall surface 1 perpendicular to the irradiation direction of the scattered light 5s
can also be exposed. However, when the scattered light 5s is used, the exposure accuracy becomes low. That is, the electrodeposited resist 3 cannot be accurately exposed with only the scattered light 5s. Therefore, the parallel light exposure step of irradiating the predetermined electrodeposition resist 3 by irradiating the parallel light 5h and the wall surface 1s substantially perpendicular to the exposure plane mask 4 by irradiating the scattered light 5s.
Since there is a scattered light exposure step of exposing the electrodeposition resist 3 formed on the substrate 1, if there are a plurality of wall surfaces 1s substantially perpendicular to the exposure plane mask 4, these wall surfaces 1s substantially perpendicular to each other.
It is possible to reliably expose the electrodeposition resist 3 formed on the predetermined substantially vertical wall surface 1s selectively from the above.

Therefore, as shown in FIG. 1D, the electrodeposition resist 3 in the unexposed portion is dissolved and removed by a developing solution such as an alkaline aqueous solution, and the conductive layer 2 is exposed in the unexposed portion, so that the exposed portion is not exposed. The deposition resist 3 serves as a resist 3a and covers the conductive layer 2. That is, on the three-dimensional surface of the insulating substrate composed of the three-dimensional molded product 1, which is the vertical wall surface 1s, the resist 3a is not formed on the resist unnecessary surface, and the resist required surface such as the through hole 7 is formed. The resist 3a can be formed. Of course, by changing the order of exposure,
As shown in FIG. 1C, after the exposure with the scattered light 5s through the exposure flat mask 4, as shown in FIG.
The parallel light 5h may be used for the exposure. On the other hand, when the photo-dissolving (positive type) electrodeposition resist 3 is used, conversely, the electrodeposition resist 3 in the exposed area is dissolved and removed by the developing solution, and the conductive layer 2 is exposed in the exposed area and unexposed. The part of the electrodeposition resist 3 serves as a resist 3a and covers the conductive layer 2. The exposed conductive layer 2 is chemically dissolved by an etching solution such as a cupric chloride solution by development. After the etching is completed, the used resist 3a is stripped with a stripping solution such as methylene chloride to form a printed wiring circuit 2p on the conductive layer 2 as shown in FIG. 1 (e). That is, when the photo-curable electrodeposition resist 3 is used, the printed wiring circuit 2p is formed in the exposed portion, and the photo-melting electrodeposition resist 3 is formed.
On the contrary, when the printed wiring circuit 2 is used in the unexposed portion,
p will be formed.

As described above, when the three-dimensional surface of the insulating substrate made of the three-dimensional molded product 1 has a plurality of wall surfaces 1s substantially perpendicular to the exposure flat mask 4 arranged on the three-dimensional molded product 1. Then, the electrodeposition resist 3 formed on the predetermined substantially vertical wall surface 1s is selectively exposed from the substantially vertical wall surface 1s by irradiating scattered light 5s through the exposure plane mask 4. Since the exposure is performed in the scattered light exposure step, the electrodeposition resist 3 formed on the predetermined vertical wall surface 1s can be reliably exposed.

FIG. 2 shows a second embodiment. As shown in FIG. 2A, the same as in the first embodiment, on the entire surface of the three-dimensional molded product 1 having a concave and convex shape provided with through holes 7 such as through holes which serve as a three-dimensional insulating substrate of the printed wiring board. Then, the conductive layer 2 for the circuit conductor is formed, and then the electrodeposition resist 3 having photosensitivity, for example, the photocurable (negative) electrodeposition resist 3 is formed on the surface of the conductive layer 2. The through hole 7 is
For example, it may have a stepped portion formed by the vertical wall surface 1s such that the space 7a having a large cross-sectional area and the space 7s having a small cross-sectional area communicate with each other. As shown in FIG. 2B, a diffused reflection plate 8h is provided on the surface of the three-dimensional molded product 1 on the side of the opening 7k having a small space 7s having a small cross-sectional area of the through hole 7. As the diffused reflection plate 8h, for example, a metal plate having fine irregularities on the surface is used, and diffuses the scattered light 5s when the light hits. On the surface of the three-dimensional molded product 1 on the side of the large opening 7t of the space 7a having a large cross-sectional area of the through hole 7,
An exposure plane mask 4 is provided. Parallel light 5h is emitted through the exposure plane mask 4. The parallel light 5h strikes the diffused reflector 8h and diffusely reflects the scattered light 5s. The diffused scattered light 5s exposes a predetermined electrodeposition resist 3 formed on the vertical wall surface 1s of the space 7s having a small cross-sectional area.

Next, on the surface of the three-dimensional molded article 1 on the side of the large opening 7t, a light absorbing plate 8k such as a black rubber plate is provided in place of the exposure flat mask 4, and the small opening is provided. On the surface of the three-dimensional molded article 1 on the 7k side, a light diffuse reflection plate 8h
Instead, an exposure plane mask 4 is provided, and an exposure apparatus such as a scattering exposure machine 6s is used to irradiate scattered light 5s such as ultraviolet rays through the exposure plane mask 4 to reduce the cross-sectional area. The predetermined electrodeposition resist 3 formed on the vertical wall surface 1s of the space 7s and the predetermined electrodeposition resist 3 on the surface of the three-dimensional molded article 1 on the side of the small opening 7k are exposed. In this case, the exposure plane mask 4 is brought into close contact with the substrate to improve the cutability of the exposure on the plane. Although it is difficult to expose the predetermined electrodeposition resist 3 on the substantially vertical wall surface 1s with the parallel light 5h,
By using the scattered light 5s, exposure can be easily performed. Furthermore, when irradiating scattered light 5s such as ultraviolet rays using an exposure device such as a scattering exposure device 6s, a light absorbing plate 8k is provided on the surface of the three-dimensional molded article 1 on the side of the large opening 7t, Since the exposure flat mask 4 is arranged on the surface of the three-dimensional molded article 1 on the side of the small opening 7k, the scattered light 5s irradiated is absorbed by the light absorbing plate 8k to form a space 7a having a large cross-sectional area. The vertical wall surface 1s is prevented from being irradiated with the scattered light 5s. That is, the space 7 having a small cross-sectional area
The scattered light 5s that has entered from s is absorbed, and it becomes difficult to expose the electrodeposition resist 3 that does not need to be exposed on the vertical wall surface 1s that forms the space 7a having a large cross-sectional area, so that the desired exposure can be performed. That is, since the predetermined electrodeposition resist 3 formed on the vertical wall surface 1s can be reliably exposed, as shown in FIG. 2D, the unexposed portion of the electrodeposition resist 3 is exposed to a developing solution such as an alkaline aqueous solution. It is dissolved and removed, and the conductive layer 2 is exposed in the unexposed portion, and the electrodeposited resist 3 in the exposed portion covers the conductive layer 2 as the resist 3a. That is, on the three-dimensional surface of the insulating substrate made of the three-dimensional molded product 1, the resist 3a can be formed in the resist-needed portion without forming the resist 3a in the resist-unnecessary portion with the vertical wall surface 1s.

Of course, by changing the order of exposure, as shown in FIG.
As shown in FIG. 2C, after the exposure with the scattered light 5 s through the exposure plane mask 4, as shown in FIG.
The parallel light 5h may be used for the exposure. The exposed conductive layer 2 is chemically dissolved by an etching solution such as a cupric chloride solution by development. After etching is complete,
When the used resist 3a is stripped with a stripping solution such as methylene chloride, a printed wiring circuit 2p is formed on the conductive layer 2 as shown in FIG. 2 (e). That is, when the photo-curing type electrodeposition resist 3 is used, the printed wiring circuit 2p is formed in the exposed portion, and when the photo-melting type electrodeposition resist 3 is used, the unexposed portion is printed. The wiring circuit 2p is formed. As described above, even when the through-hole 7 has a step and one through-hole 7 has a plurality of substantially vertical wall surfaces 1s, a predetermined approximate wall surface of the substantially vertical wall surfaces 1s is used. The vertical wall surface 1s can be selectively exposed.

As described above, according to the method for manufacturing a printed wiring board according to the first and second aspects of the present invention, it is not necessary to form the inclined surface in place of the vertical wall surface 1s, and the downsized and highly functional printed wiring board is provided. A board is obtained. Further, a parallel light exposure step of irradiating the electrodeposition resist 3 by irradiating the parallel light 5h through the exposure flat mask 4 having the exposed portion 4a and the unexposed portion 4b arranged in the three-dimensional molded article 1. And a scattered light exposure step of irradiating scattered light 5s through the exposure flat mask 4 to expose the electrodeposition resist 3 formed on the wall surface 1s substantially perpendicular to the exposure flat mask 4. No need for a complicated three-dimensional mask. Moreover, the circuit pattern can be easily changed only by changing the plane mask for exposure, and more complicated substrates can be flexibly dealt with according to the combination conditions of exposure, so that the degree of freedom in circuit design is increased.

[0021]

According to the method of manufacturing a printed wiring board according to the first aspect of the present invention, when there are a plurality of wall surfaces that are substantially perpendicular to the exposure flat mask provided on the three-dimensional molded product, these Since the electrodeposition resist 3 formed on the predetermined substantially vertical wall surface is selectively exposed from the vertical wall surface in the scattered light exposure step of irradiating and exposing the scattered light through the exposure plane mask, Since the electrodeposition resist 3 formed on the predetermined vertical wall surface 1s can be surely exposed, it is not necessary to use an inclined surface in place of the vertical wall surface, and a downsized and highly functional printed wiring board can be obtained. In addition, a 3D mask with a complicated shape is not required, and the circuit pattern can be easily changed simply by changing the exposure plane mask, and it is possible to flexibly respond to more complicated substrates depending on the exposure combination conditions. The degree of freedom in design increases.

According to the method for manufacturing a printed wiring board according to the second aspect of the present invention, since the parallel light hits the diffuse reflection plate and is diffusely reflected to become scattered light, the diffused scattered light causes the flat mask for exposure to be exposed. Since the electrodeposition resist formed on the vertical wall surface is exposed, the exposure to the electrodeposition resist formed on the predetermined substantially vertical wall surface is further ensured. Moreover, the scattered light that has been irradiated is absorbed by the light absorbing plate and is prevented from irradiating the scattered light onto the vertical wall surface that does not require exposure, so that it is formed on the vertical wall surface that does not require exposure. Since the electrodeposited resist is hard to be exposed, the accuracy of the printed wiring circuit is further improved. That is, even when the through hole has a step portion and one through hole has a plurality of substantially vertical wall surfaces, a predetermined substantially vertical wall surface is selectively exposed among these substantially vertical wall surfaces. can do.

[Brief description of drawings]

FIG. 1 is a first method of manufacturing a printed wiring board according to the present invention.
It is sectional drawing which shows an Example.

FIG. 2 is a second method of manufacturing a printed wiring board according to the present invention.
It is sectional drawing which shows an Example.

FIG. 3 is a cross-sectional view of a method for manufacturing a printed wiring board according to a conventional example.

FIG. 4 is a cross-sectional view when a positive electrodeposition resist is used in a method for manufacturing a printed wiring board according to a conventional example.

FIG. 5 is a cross-sectional view when a negative electrodeposition resist is used in a method for manufacturing a printed wiring board according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Three-dimensional molded article 2 Conductive layer 2p Printed wiring circuit 3 Electrodeposition resist 3a Resist 4 Exposure plane mask 4a Exposed part 4b Unexposed part 5h Parallel light 5s Scattered light 7 Through hole 7k Small opening 7t Large opening 8h Light diffuse reflection plate 8k light absorption plate

Claims (2)

[Claims] 1. A conductive layer (2) is formed on the surface of an insulating three-dimensional molded article (1), and a photosensitive electrodeposition resist (3) is formed on the conductive layer (2). Through holes (7) for forming a printed wiring circuit (2p) by irradiating light through an exposure plane mask (4) to expose and develop an electrodeposition resist (3) to form a resist (3a). In the method for manufacturing a printed wiring board having a plurality of substantially perpendicular wall surfaces (1s) with respect to the exposure flat mask (4), the exposure unit (4) provided on the three-dimensional molded product (1).
a parallel light exposure step of irradiating parallel light (5h) to expose a predetermined electrodeposition resist (3) through an exposure flat mask (4) including a) and an unexposed portion (4b); The scattered light (5 s) is irradiated through the exposure plane mask (4) and a predetermined substantially vertical wall surface (1) with respect to the exposure plane mask (4).
and a scattered light exposure step of exposing the electrodeposition resist (3) formed in s) to a method for producing a printed wiring board. 2. The through hole (7) has a step, and a diffused reflection plate (8h) is arranged on the surface of the three-dimensional molded product (1) on the side of the opening (7k) where the through hole (7) is small. And a small opening (7
k), and a plane mask for exposure (4) is arranged on the surface of the three-dimensional molded article (1) on the side of the opening (7t) having a large through hole (7). Parallel light (5
parallel light exposure step of irradiating a predetermined electrodeposition resist (3) by irradiating h), and disposing a light absorbing plate (8k) on the surface of the three-dimensional molded product (1) on the side of the large opening (7t). To cover the large opening (7t), and dispose the exposure flat mask (4) on the surface of the three-dimensional molded product (1) on the side of the small opening (7k). Scattered light (5
The method for producing a printed wiring board according to claim 1, further comprising: a scattered light exposure step of irradiating a predetermined electrodeposition resist (3) by irradiating s).