JP4914796B2 - Wiring board manufacturing method and wiring board - Google Patents

Description

  The present invention relates to a method for manufacturing a wiring board and a wiring board in which a wiring pattern is formed using an ink containing metal particles on the inner surface of a hollow part of a substrate body having a hollow part communicating with the outside.

Conventionally, a method for manufacturing a wiring board in which a wiring pattern is formed using ink containing metal particles is known.
For example, in Patent Document 1, an insulating substrate having a water-repellent film formed on the surface is disposed on an XY table, and the water-repellent film is removed according to the wiring pattern by laser light, thereby exposing the insulating substrate. The above describes a method for forming a conductor circuit in which a wiring pattern is drawn by ejecting ink particles containing conductive ultrafine particles using an inkjet nozzle.
JP 2003-188497 A

However, the conventional method for manufacturing a wiring board as described above has the following problems.
In the technique described in Patent Document 1, a wiring pattern is drawn by ejecting ink particles including conductive ultrafine particles from an inkjet nozzle and relatively moving the positions of the insulating substrate and the inkjet nozzle. Since the ink jet nozzle is provided on the end face of the ink jet head in which the ink supply unit and the ejection mechanism drive circuit are integrated, it has a size of at least several centimeters and is placed close to the surface of the substrate to be drawn. Need to be done.
Therefore, although it is possible to manufacture a plate-like wiring board that is developed in a plane, for example, when forming a wiring pattern on the inner surface of a three-dimensional object having a hollow portion such as a tube shape or a bottle shape, Since an insertable opening and space are required, there is a problem that the size and shape of the wiring board are significantly restricted.

  The present invention has been made in view of the above problems, and can reduce the size and shape restrictions, and can be easily manufactured, and has a light-transmitting property having a hollow portion communicating with the outside. An object of the present invention is to provide a method of manufacturing a wiring board having a wiring pattern on the inner surface of the hollow portion of the board body, and a wiring board.

In order to solve the above-described problems, a method for manufacturing a wiring board according to the present invention includes forming a wiring pattern on the inner surface of a hollow portion of a substrate body having a hollow portion communicating with the outside using an ink containing metal particles. The substrate body is made of a light-transmitting material, and a film-forming step of forming an ink-repellent film that repels the ink on the inner surface of the hollow portion of the substrate body; and A focused laser beam is irradiated from the outside of the hollow portion so that the substrate main body on which the ink-repellent film is formed in the film forming step passes through the substrate main body, and is applied to the wiring pattern. A groove processing step of processing a groove reaching at least a depth at which the substrate main body is exposed to the inner surface side of the hollow portion on an inner surface of the hollow portion at a corresponding position; and the substrate main body on which the groove is processed by the groove processing step. ,in front A dipping step in which the metal particles in the ink are adhered in the groove, and a baking step in which the metal particles attached in the groove by the dipping step are heated to a baking temperature or higher to be baked. A method comprising
According to this invention, a film having an ink repellency that repels ink containing metal particles is formed on the inner surface of the hollow portion of the light-transmitting substrate main body by the film forming step, and then the groove processing step is performed on the substrate main body. On the other hand, by irradiating condensed laser light from the outside of the hollow part, a groove reaching at least the depth at which the substrate body is exposed to the inner side of the hollow part is processed on the inner surface of the hollow part at a position corresponding to the wiring pattern. To do. Then, by performing the dipping process, the substrate body that has undergone the film forming process and the groove processing process is simply dipped into the ink containing metal particles in the dipping process, and the grooves formed on the inner surface of the hollow portion of the substrate body Metal particles can be deposited inside. At this time, since an ink-repellent film is formed on the inner surface of the hollow portion excluding the groove formed at the position corresponding to the wiring pattern, the ink containing the metal particles is repelled and the metal particles adhere to the substrate body. There is nothing. And the wiring pattern by a metal particle layer can be formed by only heating and baking the metal particle adhering in a groove | channel by a baking process after an immersion process.
That is, since the ink containing metal particles is adhered in the grooves by the dipping process, the ink containing the metal particles is drawn on the inner surface of the hollow portion of the substrate body having a hollow portion communicating with the outside without drawing with an inkjet head or the like. A wiring pattern can be formed along the groove shape formed in the processing step. Further, since the substrate body is irradiated with laser light from the outside of the hollow portion in the groove processing step, the groove processing can be performed even when the opening of the hollow portion communicating with the outside or the space inside the hollow portion is narrow.

Moreover, in the manufacturing method of the wiring board of this invention, it is preferable to provide the plating process of laminating | stacking on the said metal particle layer baked by the said baking process, and forming a plating layer.
In this case, since the plating layer is formed by laminating on the fired metal particle layer by the plating step, a robust wiring pattern can be formed. In addition, the thickness of the wiring pattern can be easily adjusted.

In the method for manufacturing a wiring board according to the present invention, it is preferable that the film forming step forms the ink-repellent film with a light-transmitting material.
In this case, in the groove processing step, laser light is irradiated from the outside of the substrate main body facing the wiring pattern, so that the laser light passing through the hollow portion is transmitted through the ink-repellent film facing the wiring pattern. The film portion having ink repellency corresponding to the position of the wiring pattern can be irradiated. For this reason, laser light can pass through the substrate body with a large beam diameter and be condensed at the groove processing position, so even if there is a noise factor that generates scattered light such as scratches or foreign matter on the substrate body Good groove processing can be performed.

The wiring board of the present invention has a structure manufactured by the method for manufacturing a wiring board according to any one of claims 1 to 3.
According to this invention, since it is manufactured by the method for manufacturing a wiring board according to the present invention, the same effects as the method for manufacturing a wiring board according to the present invention are provided.

  According to the method for manufacturing a wiring board and the wiring board of the present invention, the hollow portion is formed on the inner surface of the hollow portion of the substrate body having a hollow portion communicating with the outside without drawing ink containing metal particles by an inkjet head or the like. Since the wiring pattern can be formed along the groove formed by the laser beam irradiated from the outside, the size and shape of the substrate main body can be reduced, and the manufacturing can be easily performed.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. In all the drawings, even if the embodiments are different, the same or corresponding members are denoted by the same reference numerals, and common description is omitted.

[First Embodiment]
A method for manufacturing a wiring board and a wiring board according to a first embodiment of the present invention will be described.
FIG. 1A is a schematic plan view of a wiring board manufactured by the manufacturing method according to the first embodiment of the present invention. FIG. 1B is a side view as viewed from B in FIG. FIG. 2 is a cross-sectional view taken along line AA in FIG. FIG. 3 is a cross-sectional view taken along the line CC in FIG. 4 is a partially enlarged view of FIG. In each drawing, the dimensional ratio of each part is exaggerated for easy viewing (the same applies to the following drawings).

  As shown in FIGS. 1 to 4, the wiring substrate 1 manufactured by the method for manufacturing a wiring substrate according to the present embodiment has an inner surface of a cylindrical tubular base material 10 that is curved in an S shape as a wiring body 13. As shown, a wiring pattern composed of a plurality of conductive patterns 34A, 34B, and 34C is formed.

The base material 10 is made of, for example, an insulating light-transmitting material such as a glass material, and the inner peripheral surface of the base material 10 excluding the conductive patterns 34A, 34B, and 34C and the outer peripheral surface of the base material 10 are These are covered with water repellent films 31A and 31B made of an insulating material, respectively. Here, the water repellent film 31A does not necessarily have light transmittance, but in the following, the water repellent films 31A and 31B are formed of a water repellent of the same material having light permeability. This will be explained with an example.
The inner diameter of the wiring board 1 can be appropriately set as necessary, but in this embodiment, as an example, the inner diameter is set to 5 mm.
The base material 10 and the water repellent film 31 </ b> B have such a transmittance that at least a laser beam 52 used for groove processing, which will be described later, is transmitted from the outside of the base material 10 and reaches the inner peripheral surface of the base material 10. As long as it is visible and does not have to be visible.

Here, the wiring board 1 is an S-shaped cylindrical tube that is an example, and is not limited to the cylindrical tube, and the tube cross section may be, for example, an elliptical cross section, a polygonal column cross section, or each side of a polygonal column. A tubular structure having an appropriate cross section such as a curved cross section can be employed. Further, the curved shape is not limited to the S shape, and may not be curved. Further, the cross-sectional shape of the wiring board 1 may be changed in size and shape in the axial direction.
In addition, the shape is not necessarily limited to a tubular shape as long as it has a hollow portion communicating with the outside. For example, one end 1A in the axial direction of the wiring board 1 is opened and the other end 1B is closed. The bottomed cylindrical shape may be sufficient. Alternatively, the bottomed cylindrical opening may have a small inner diameter on the opening side and a bottle-like shape with a large inner diameter on the bottom side.

In the present embodiment, the conductive patterns 34A, 34B, and 34C are, for example, three substantially linear patterns that electrically connect the end portions 1A and 1B of the wiring board 1, as shown in FIG. As shown in FIG. 2, they are spaced apart in the circumferential direction and provided approximately in parallel.
As shown in FIG. 3, the conductive pattern 34B has a rectangular terminal portion 34b on the end 1A side, and the wiring portion 34a is formed on the opposite side of the end portion 1A of the terminal portion 34b. It has been extended. Further, as shown in FIG. 1A, a similar shape is formed in the vicinity of the end 1B.
Further, as shown in FIGS. 3 and 4, the conductive pattern 34A has a rectangular terminal portion 34b on the end 1A side, as shown in FIGS. 3 and 4, and from the side opposite to the end 1A of the terminal portion 34b. The wiring portion 34 a is extended along the axial direction of the base material 10 after extending in an oblique direction toward the conductive pattern 34 </ b> B. Further, as shown in FIG. 1A, a similar shape is formed in the vicinity of the end 1B.
The conductive pattern 34C is obtained by providing the conductive pattern 34A symmetrically with respect to the central axis of the conductive pattern 34B.
As a result, the wiring substrate 1 is inserted into the openings of the end portions 1A and 1B by inserting male connectors having terminal portions corresponding to the positions of the three terminal portions 34b spaced apart in the circumferential direction. 10 can be used as a cylindrical wiring member whose outer peripheral side is protected by S and curved in an S shape.

As shown in FIG. 2, the conductive patterns 34 </ b> A, 34 </ b> B, 34 </ b> C are configured with grooves 32 extending from the water repellent film 31 </ b> A on the inner peripheral surface side to the base material 10. From the bottom of the groove, a silver particle layer 33B (metal particle layer) and a plating layer 35 are laminated in this order.
In the present embodiment, an example in which the groove 32 is formed up to the inside of the substrate 10 will be described. However, the groove 32 only needs to have a depth at which the substrate 10 is exposed.

The silver particle layer 33B is obtained by baking a so-called silver nano-ink formed by finely dividing silver into nano-order particles and independently dispersing without aggregation in a solvent. Although the silver nanoink of this embodiment is demonstrated by the case where water is used as a solvent, the kind of solvent will not be limited if it is a solvent which can contain the independent dispersion | distribution particle | grains of silver.
For example, since the silver nano ink of the present embodiment is not used by being ejected from an inkjet nozzle, it may be a viscous solvent that cannot be ejected from the inkjet nozzle, or a solvent that has poor ejection performance or landing performance from the inkjet nozzle. It can be suitably employed.
In the present embodiment, the plating layer 35 is made of copper. However, the material of the plating layer 35 is not limited to this, and may be formed of other conductive metals such as gold.

  The material of the water repellent films 31A and 31B can be any appropriate material as long as it is a light-transmitting material that can be coated on the base material 10 and has water repellency (ink repellency) to repel silver nanoink. Can be adopted. In this embodiment, in particular, an insulating material is used to insulate the conductive patterns 34A, 34B, and 34C. As an example of the water repellent of such an insulating material, for example, a water repellent such as PTFE (polytetrafluoroethylene) can be cited.

Next, the manufacturing method of the wiring board 1 of this embodiment is demonstrated.
FIG. 5 is a flowchart for explaining the process flow of the method for manufacturing a wiring board according to the first embodiment of the present invention. 6A, 6 </ b> B, 6 </ b> C, 6 </ b> D, and 6 </ b> E are process explanatory views of the manufacturing method of the wiring board according to the first embodiment of the present invention. FIG. 7A is a process explanatory diagram for explaining a groove machining process of the method for manufacturing a wiring board according to the first embodiment of the present invention.

  As shown in FIG. 5, the manufacturing process of the method for manufacturing a wiring board according to the present embodiment includes a film forming process S1, a groove processing process S2, an immersion process S3, a baking process S4, and a plating process S5 in this order. It is.

First, in the film forming step S1, the inner peripheral surface and the outer peripheral surface of the substrate 10 are coated with an insulating water repellent to form water repellent films 31A and 31B, which are ink repellent films that repel ink (respectively) ( (See FIG. 6 (a)). However, Fig.6 (a) has shown only the partial cross section by the side of the inner surface of the base material 10 (henceforth other FIG.6 (b)-(e) is also the same).
The reason why the film formed in the film forming step S1 is water-repellent is that, in this embodiment, silver nano ink using water as a solvent is used.
The water repellent coating method is not particularly limited as long as the water repellent films 31 </ b> A and 31 </ b> B can be formed on the inner peripheral surface and the outer peripheral surface of the substrate 10. For example, when the water repellent is made of PTFE, a spraying method or a dipping method can be employed.

Next, in the groove processing step S2, a part of the water-repellent film 31A is removed from the inner surface side of the hollow portion of the base material 10 on which the water-repellent film 31A is formed, and at least the base material 10 is exposed. A groove 32 is formed.
In the present embodiment, as shown in FIG. 7A, a laser light source 51 for irradiating laser light 52 condensed toward the base material 10 from the outside of the base material 10 is used as the outer periphery of the base material 10. Arrange it so that it can move along the surface. Then, with the focal position of the laser light source 51 set in the vicinity of the water repellent film 31 </ b> A, the laser light 52 is irradiated toward the water repellent film 31 </ b> A in the substrate 10. Then, the laser light source 51 is moved so that the irradiated position of the laser light 52 scans the range in which the conductive patterns 34A, 34B, and 34C are formed on the wiring region 13.
The laser beam 52 is incident on the water-repellent film 31B from the outside of the base material 10 while being gradually collected, passes through the water-repellent film 31B and the base material 10, and is condensed to a predetermined spot diameter, thereby repelling the water. It reaches the water film 31A. Therefore, the water repellent film 31 </ b> A is removed by the light energy concentrated in the irradiation part of the laser beam 52. Further, the substrate 10 in the vicinity of the water repellent film 31A is also removed according to the irradiation time and the laser output. At this time, the laser beam 52 is not condensed on the portion of the substrate 10 that is away from the water repellent film 31A or the water repellent film 31B, and is not removed because the light energy density is low.
In this manner, the grooves 32 for forming the conductive patterns 34A, 34B, and 34C are formed (see FIGS. 6B and 7A).
The wavelength and output of the laser light source 51 can be appropriately set according to the material to be processed. In this embodiment, depending on the material of the water repellent film 31 </ b> A and the substrate 10, an appropriate wavelength and output that can be removed are set. Further, when laser light 52 having different wavelengths is required between the water repellent film 31A and the substrate 10, the laser light source 51 is configured to be able to oscillate a plurality of wavelength lights, and is processed by switching the wavelengths as appropriate.

Although not particularly illustrated, in the present embodiment, the laser light source 51 is supported so that the focal position of the laser light 52 is constant on the wiring region 13 even if the irradiation position of the laser light 52 is changed. Yes. For example, the laser light source 51 is fixed to a position relative to the base material 10 and includes a focal position changing unit, or is supported by a moving mechanism that moves in the axial direction outside the base material 10.
Thereby, for example, even if the wiring region 13 of the substrate 10 is curved, the groove 32 having a certain depth can be formed by changing the focal position of the laser beam 52.
In such a groove processing step S2, the substrate 10 and the laser light source 51 only need to be able to move relative to each other. The laser light source 51 is fixed and the substrate 10 is moved, or the laser light source 51 and the substrate 10 The laser beam 52 may be scanned by moving each other.

Next, in the immersion step S3, the base material 10 on which the grooves 32 are formed is immersed in the silver nano ink 33A whose solvent is water, and the silver nano ink 33A is adhered to the grooves 32 of the base material 10.
At this time, in the wiring region 13, since the inner peripheral surface of the substrate 10 other than the grooves 32 is covered with the water repellent film 31A, the silver nano ink 33A is repelled by the water repellent action of the water repellent film 31A. Therefore, the silver nano ink 33A is not attached to the region covered with the water repellent film 31A (see FIG. 6C).
Similarly, since the outer peripheral surface of the base material 10 is also covered with the water-repellent film 31B, the silver nano ink 33A is not attached.
After the immersion, the silver nano ink 33A attached to the end portions 1A and 1B is removed by, for example, wiping, and then the silver nano ink 33A attached to the groove 32 is dried.
In addition, by forming a water repellent film on the end portions 1A and 1B in advance, the silver nano ink 33A is prevented from adhering, and the water repellent film adhering to the end portions 1A and 1B is removed later. May be.

Next, in baking process S4, the base material 10 with the silver nano ink 33 attached to the groove 32 is heated for 30 minutes in a heating furnace set at 120 ° C., for example, to fire the silver nano ink 33A.
Thereby, the silver particle layer 33B is formed in the groove | channel 32 (refer FIG.6 (d)).

Next, in the plating step S5, the plating layer 35 is formed on the silver particle layer 33B formed in the baking step S4 (see FIG. 6E). In this embodiment, the base material 10 is placed in an electroless copper plating bath, whereby the copper plating layer 35 is formed to a height substantially equal to the water repellent film 31A.
In this manner, the wiring board 1 having the conductive patterns 34A, 34B, and 34C on the inner surface of the hollow portion is manufactured by the wiring board manufacturing method of the present embodiment.

According to the method for manufacturing a wiring board of the present embodiment, since the film forming step S1, the groove processing step S2, the dipping step S3, and the firing step S4 are sequentially performed on the substrate 10, the base material 10 Even if it has a shape having a hollow portion communicating with the outside, it is possible to easily form the conductive patterns 34A, 34B, and 34C along the groove 32 on the inner surface of the hollow portion.
For this reason, the conductive patterns 34A, 34B, and 34C can be formed more quickly than when the wiring pattern is drawn by repeatedly discharging the silver nano ink 33A from the inkjet head onto the wiring region 13. . Further, even when the substrate body does not have an opening or space for inserting an inkjet head, the conductive patterns 34A, 34B, and 34C can be formed on the inner surface of the hollow portion, thereby reducing the size and shape restrictions. it can.
For example, in the present embodiment, an example in which the diameter of the inner peripheral portion of the hollow portion is 5 mm has been described. However, even if the inner diameter is smaller, the laser beam 52 according to the groove width corresponding to the line width of the wiring pattern. It is possible to form a wiring pattern by setting the spot diameter and setting the focal depth so that an appropriate groove depth can be obtained. Therefore, even when the hollow portion has only a small opening or space in which an ink jet head of about several centimeters square cannot be inserted, the wiring pattern can be formed on the inner surface of the hollow portion, and the wiring board 1 can be remarkably reduced in size.

Further, by forming the water repellent film 31A in the film forming step S1, the silver nano ink 33A used in the dipping step S3 can be attached only to the groove 32, so that the amount of the silver nano ink 33A to be used is reduced and the ink cost is reduced. Can be reduced.
Furthermore, since a water repellent agent having an insulating property is used for the water repellent film 31A in the film forming step S1, even if the water repellent film 31A is left, the wiring patterns do not short through the water repellent film 31A. For this reason, the removal process of the water repellent film 31A can be omitted, and the number of work steps can be reduced.

Moreover, since the wiring board 1 of this embodiment forms the plating layer 35 on the silver particle layer 33B by the plating step S5, the thickness of the plating layer 35 can be adjusted even if a small amount of the silver nano ink 33A is used. Thus, the thickness and strength of the conductive patterns 34A, 34B, and 34C can be changed as necessary. Therefore, since the usage amount of the silver nano ink 33A can be reduced, the conductive patterns 34A, 34B, and 34C can be manufactured at a lower cost than when the silver nano ink 33A is formed alone.
In addition, since copper is less liable to cause ion migration than silver, there is an accompanying effect that the plating process can reduce the concern about the occurrence of ion migration of the wiring board 1 and can improve electrical stability. Play.

Next, a first modification of the present embodiment will be described.
The wiring substrate 1 of the first embodiment has a configuration in which the water-repellent films 31A and 31B are left on the inner peripheral surface and the outer peripheral surface, respectively. Since the silver nano ink 33A is dried in the dipping step S3, the silver nano ink 33A can be removed.
Although not particularly shown, the wiring board of this modification is obtained by removing at least one of the water-repellent films 31A and 31B that do not need to remain on the surface of the wiring board 1 from the wiring board 1 of the first embodiment. is there.
The removal processing of the water repellent films 31A and 31B may be performed after drying the silver nano ink 33A and before entering the heating furnace in the baking step S4, or may be performed after baking and after removing from the heating furnace. Good. However, firing the silver nano ink 33A attached to the grooves 32 in the presence of the water repellent film 31A can form a more accurate wiring pattern. Therefore, the removal process of the water repellent film 31A is performed in the firing step S4. It is more desirable to do after.
If such a removal step of the water repellent film 31A (31B) is provided, a conductive material may be adopted as the water repellent film 31A (31B).

Next, a second modification of the present embodiment will be described.
FIG. 7B is a process explanatory view illustrating the groove processing process of the method for manufacturing the wiring board according to the second modification of the first embodiment of the present invention.

This modification is an example of a laser irradiation method in the case where both the water repellent films 31A and 31B have light transmittance.
In this modification, as shown in FIG. 7B, the laser beam 52 is incident from the outside of the base material 10 facing the formation position of the groove 32, and the water repellent film 31B, the base material 10, The water film 31A is allowed to pass through, and the water repellent film 31A is irradiated from the inside of the hollow portion of the substrate 10.
In this case, since the diameter of the laser beam 52 is relatively large on the opposite position side of the groove 32, the removal process is not performed.

  According to the present modification, for example, even when the base material 10 includes a scratch or a foreign substance having a size close to the spot diameter when the light is condensed, the laser beam 52 is transmitted with a large beam diameter. The amount of light that is scattered by the laser light 52 due to such scratches and foreign matter is reduced, and the amount of collected light can be stabilized. Therefore, groove processing with little unevenness can be performed.

[Second Embodiment]
A method for manufacturing a wiring board and a wiring board according to a second embodiment of the present invention will be described.
FIG. 8 is a schematic cross-sectional view corresponding to the AA cross section in FIG. 1 of the wiring board according to the second embodiment of the present invention.

  In the wiring substrate 100 of the present embodiment, the conductive patterns 34A, 34B, and 34C of the wiring substrate 1 of the first embodiment are formed only by the silver particle layer 33B.

Such a wiring board 100 can be manufactured by omitting the plating step S5 in the manufacturing process of the wiring board 1 of the first embodiment.
Therefore, the wiring board 100 has the same functions and effects as those of the first embodiment except for the functions and effects related to the plating layer 35 of the wiring board 1 of the first embodiment.
According to the wiring board 100, since the plating layer 35 is not provided, the plating process S5 can be omitted and the manufacturing process can be simplified.

  In the above description, an example in which the silver nano-ink 33A is used as the ink containing metal particles has been described. However, metal particles other than silver are included as long as the metal particles can form independent dispersed fine particles. Ink may be used.

Moreover, in description of said 1st Embodiment, although the base material 10 was put into the electroless copper plating bath in plating process S5, and the plating layer 35 was formed, what kind of thing will be sufficient if the plating layer 35 is formed? A plating method may be used.
The metal to be plated is not limited to copper, but may be any conductive metal such as nickel or palladium. However, a metal that is less liable to cause ion migration than the metal fired on the substrate 10 is desirable.

  In the above description, as an example, in the baking step S4, the base material 10 is heated in a heating furnace set at 120 ° C. for 30 minutes, but the baking conditions are not limited thereto. If the silver in the silver nano ink 33A is baked and the base material 10 is not deformed by heat, the heating temperature, time, and method are not limited.

  In the above description, an example in which a plurality of wiring portions 34a that connect the two terminal portions 34b are provided as the wiring pattern has been described. However, the shape of the wiring pattern is as long as the groove 32 can be processed. The shape can be appropriately set as required. That is, for example, a circuit such as a coil may be formed, or a wiring for connecting an electric element or an electronic component may be formed.

  In the above description, an example in which the substrate body is made of a glass material has been described. However, as long as it is a light-transmitting insulator that can be grooved, a synthetic resin or another dielectric may be used.

In the above description, the silver particle layer 33 </ b> B is formed in the groove 32 to fill the groove 32, but the silver particle layer is formed in the groove 32 formed inside the substrate 10. 33B and the plating layer 35 may be laminated.
In such a wiring board, in the immersion step S3 of the first embodiment, for example, after the base material 10 is immersed, a part of the silver nano ink 33A in the groove 32 is discharged from the end portions 1A, 1B, and the like. Then, the adhesion amount of the silver nano ink 33A in the groove 32 is controlled so that the dried silver particle layer 33B is formed so as not to fill up the groove 32 in the base material 10, and the plating is performed thereon. It can be manufactured by forming the layer 35 and filling the groove 32.
The plating layer 35 may be provided until it is aligned with the water repellent film 31 </ b> A, or may be limited to the position of the inner peripheral surface of the substrate 10.
In the latter case, if the water-repellent film 31 </ b> A is removed, the conductive patterns 34 </ b> A, 34 </ b> B, 34 </ b> C that have the plating layer 35 on the surface and do not protrude from the inner peripheral surface of the substrate 10 can be formed.

  Further, the constituent elements described in the above embodiments and modifications can be implemented in appropriate combination within the scope of the technical idea of the present invention, if technically possible.

It is the typical top view of the wiring board manufactured by the manufacturing method of the 1st Embodiment of this invention, and its B view side view. It is AA sectional drawing in Fig.1 (a). It is CC sectional drawing in FIG.1 (b). It is the elements on larger scale of the D view in FIG. It is a flowchart explaining the process flow of the manufacturing method of the wiring board which concerns on the 1st Embodiment of this invention. It is process explanatory drawing of the manufacturing method of the wiring board which concerns on the 1st Embodiment of this invention. It is process explanatory drawing explaining the groove processing process of the manufacturing method of the wiring board which concerns on the 1st Embodiment of this invention and its 2nd modification. It is typical sectional drawing equivalent to the AA cross section in FIG. 1 of the wiring board which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

1, 100 Wiring board 10 Base material (board body)
13 wiring region 31A, 31B water repellent film (film having ink repellency)
32 Groove 33A Silver nano ink (ink containing metal particles)
33B Silver particle layer (metal particle layer)
34A, 34B, 34C Conductive pattern (wiring pattern)
35 Plating layer 52 Laser beam S1 Film forming step S2 Groove processing step S3 Immersion step S4 Firing step S5 Plating step

Claims (4)

A method of manufacturing a wiring board, wherein a wiring pattern is formed using an ink containing metal particles on the inner surface of a hollow part of a substrate body having a hollow part communicating with the outside,
A film forming step in which the substrate body is made of a light-transmitting material, and a film having ink repellency that repels the ink is formed on the inner surface of the hollow portion of the substrate body;
The wiring pattern is irradiated with a focused laser beam from the outside of the hollow portion so that the substrate body on which the ink-repellent film is formed in the film forming step is transmitted through the substrate body. A groove processing step of processing a groove reaching at least the depth at which the substrate body is exposed to the inner surface side of the hollow portion on the inner surface of the hollow portion at a position corresponding to
Immersion step of immersing the substrate body having the groove processed by the groove processing step in the ink, and attaching the metal particles in the ink to the groove;
A method of manufacturing a wiring board, comprising: a firing step in which the metal particles attached in the groove by the dipping step are heated to a firing temperature or higher.   The method for manufacturing a wiring board according to claim 1, wherein the film forming step forms the ink-repellent film using a light-transmitting material.   The method for manufacturing a wiring board according to claim 1, further comprising a plating step of forming a plating layer by laminating on the metal particle layer fired by the firing step.   A wiring board manufactured by the method for manufacturing a wiring board according to claim 1.

Images