JP2021141184A - Circuit formation method - Google Patents

Abstract

To appropriately expose a part of wiring in an opening.SOLUTION: The present invention relates to a circuit formation method including: a wiring forming step of forming wiring by coating a substrate with a conductive fluid which is heated to present conductivity; and a resin layer forming step of forming on the substrate a resin layer including an opening where a part of the wiring is exposed, by coating the substrate with a curable resin so as to expose a part of the wiring. The resin layer forming step is a step of discharging the curable resin in such a manner that a margin of the curable resin covering the wiring to the opening is separated from the opening more than a margin of the curable resin covering the substrate to the opening in the case where wettability of the wiring and the curable resin is higher than wettability of the substrate and the curable resin, and is a step of discharging the curable resin in such a manner that the margin of the curable resin covering the substrate to the opening is separated from the opening more than the margin of the curable resin covering the wiring to the opening in the case where the wettability of the substrate and the curable resin is higher than the wettability of the wiring and the curable resin.SELECTED DRAWING: Figure 11

Description

The present invention relates to a method of forming a circuit of a circuit including wiring formed by using a conductive fluid that develops conductivity by heating.

As described in the following patent documents, a technique relating to a circuit forming method of a circuit for forming wiring using a conductive fluid that exhibits conductivity by heating has been developed in recent years.

International Publication No. 2014/041670

The wiring may be covered with a curable resin for the purpose of protecting the wiring formed by the conductive fluid. In such a case, an opening is formed in the resin layer formed of the curable resin in order to ensure continuity to the wiring, and a part of the wiring is exposed at the opening. Therefore, it is an object of the present invention to appropriately expose a part of the wiring at the opening.

In order to solve the above problems, the present specification describes a wiring forming step of applying a conductive fluid that develops conductivity by heating onto a base material to form wiring, and exposing a part of the wiring. The resin layer forming step includes a resin layer forming step of applying a curable resin on the base material and forming a resin layer having an opening in which a part of the wiring is exposed on the base material. When the wettability between the wiring and the curable resin is higher than the wettability between the base material and the curable resin, the edge of the curable resin covering the wiring to the opening forms the base material. It is a step of discharging the curable resin so as to be separated from the opening from the edge of the curable resin to cover the opening, and the wettability between the base material and the curable resin is the wettability of the wiring and the curable. When the wettability with the resin is higher, the curing is such that the edge of the curable resin covering the base material to the opening is separated from the opening by the edge of the curable resin covering the wiring to the opening. A circuit forming method, which is a step of discharging a sex resin, is disclosed.

In the present disclosure, the curable resin is discharged in consideration of the wettability between the wiring and the curable resin and the wettability between the base material and the curable resin. As a result, even when the curable resin gets wet and spreads, a part of the wiring can be appropriately exposed at the opening.

It is a figure which shows the circuit forming apparatus. It is a block diagram which shows the control device. It is sectional drawing which shows the circuit in the state which the resin laminate is formed. It is sectional drawing which shows the circuit in the state which the wiring is formed on the resin laminate. It is a top view which shows the circuit in the state which the wiring is formed on the resin laminate. It is sectional drawing which shows the circuit in the state which the resin laminated body is laminated on the resin laminated body and wiring. It is a top view which shows the circuit in the state which the resin laminate is laminated on the resin laminate and wiring. It is sectional drawing which shows the circuit in the state which the electronic component is attached. It is a top view which shows the circuit in the state which the electronic component is attached. It is a top view which shows the ultraviolet curable resin discharged by the conventional circuit formation method. It is a top view which shows the ultraviolet curable resin discharged by the circuit formation method of an Example. It is a top view which shows the resin laminate formed by the circuit formation method of an Example. It is a top view which shows the ultraviolet curable resin discharged by the circuit formation method of the modification. It is a top view which shows the resin laminate formed by the circuit formation method of the modification.

FIG. 1 shows the circuit forming apparatus 10. The circuit forming device 10 includes a transport device 20, a first modeling unit 22, a second modeling unit 24, a mounting unit 26, and a control device (see FIG. 2) 28. The transfer device 20, the first modeling unit 22, the second modeling unit 24, and the mounting unit 26 are arranged on the base 29 of the circuit forming device 10. The base 29 has a generally rectangular shape, and in the following description, the longitudinal direction of the base 29 is orthogonal to the X-axis direction, and the lateral direction of the base 29 is orthogonal to both the Y-axis direction, the X-axis direction, and the Y-axis direction. The direction will be described as the Z-axis direction.

The transport device 20 includes an X-axis slide mechanism 30 and a Y-axis slide mechanism 32. The X-axis slide mechanism 30 has an X-axis slide rail 34 and an X-axis slider 36. The X-axis slide rail 34 is arranged on the base 29 so as to extend in the X-axis direction. The X-axis slider 36 is slidably held in the X-axis direction by the X-axis slide rail 34. Further, the X-axis slide mechanism 30 has an electromagnetic motor (see FIG. 2) 38, and the X-axis slider 36 moves to an arbitrary position in the X-axis direction by driving the electromagnetic motor 38. Further, the Y-axis slide mechanism 32 has a Y-axis slide rail 50 and a stage 52. The Y-axis slide rail 50 is arranged on the base 29 so as to extend in the Y-axis direction, and is movable in the X-axis direction. Then, one end of the Y-axis slide rail 50 is connected to the X-axis slider 36. The stage 52 is slidably held in the Y-axis slide rail 50 in the Y-axis direction. Further, the Y-axis slide mechanism 32 has an electromagnetic motor (see FIG. 2) 56, and the stage 52 moves to an arbitrary position in the Y-axis direction by driving the electromagnetic motor 56. As a result, the stage 52 moves to an arbitrary position on the base 29 by driving the X-axis slide mechanism 30 and the Y-axis slide mechanism 32.

The stage 52 has a base 60, a holding device 62, and an elevating device 64. The base 60 is formed in a flat plate shape, and a substrate is placed on the upper surface. The holding devices 62 are provided on both sides of the base 60 in the X-axis direction. Then, both edges of the substrate mounted on the base 60 in the X-axis direction are sandwiched by the holding device 62, so that the substrate is fixedly held. Further, the elevating device 64 is arranged below the base 60 and raises and lowers the base 60.

The first modeling unit 22 is a unit for modeling wiring on a substrate mounted on a base 60 of a stage 52, and has a first printing unit 72 and a heating unit 74. The first printing unit 72 has an inkjet head (see FIG. 2) 76, and the inkjet head 76 ejects metal ink linearly. Metal ink is nanometer-sized metal fine particles dispersed in a solvent. The surface of the metal fine particles is coated with a dispersant to prevent agglutination in the solvent. Further, the inkjet head 76 ejects metal ink from a plurality of nozzles by, for example, a piezo method using a piezoelectric element.

The heating unit 74 has a heater (see FIG. 2) 78. The heater 78 is a device that heats the metal ink ejected by the inkjet head 76. The metal ink is fired by being heated by the heater 78 to form wiring. In the firing of metal ink, the solvent is vaporized and the protective film of the metal fine particles, that is, the dispersant is decomposed by applying energy, and the metal fine particles are brought into contact with each other or fused to be conductive. This is a phenomenon in which the rate increases. Then, by firing the metal ink, a metal wiring is formed.

Further, the second modeling unit 24 is a unit for modeling a resin layer on a substrate mounted on a base 60 of a stage 52, and has a second printing unit 84 and a curing unit 86. The second printing unit 84 has an inkjet head (see FIG. 2) 88, and the inkjet head 88 ejects an ultraviolet curable resin. The ultraviolet curable resin is a resin that is cured by irradiation with ultraviolet rays. The inkjet head 88 may be, for example, a piezo method using a piezoelectric element, or a thermal method in which a resin is heated to generate bubbles and discharged from a plurality of nozzles.

The curing portion 86 includes a flattening device (see FIG. 2) 90 and an irradiation device (see FIG. 2) 92. The flattening device 90 flattens the upper surface of the ultraviolet curable resin discharged by the inkjet head 88. For example, the surplus resin is scraped off by a roller or a blade while leveling the surface of the ultraviolet curable resin. Then, the thickness of the UV curable resin is made uniform. Further, the irradiation device 92 includes a mercury lamp or an LED as a light source, and irradiates the discharged ultraviolet curable resin with ultraviolet rays. As a result, the discharged ultraviolet curable resin is cured to form a resin layer.

Further, the mounting unit 26 is a unit for mounting electronic components on a substrate mounted on a base 60 of a stage 52, and has a supply unit 110 and a mounting unit 112. The supply unit 110 has a plurality of tape feeders (see FIG. 2) 114 that send out the taped electronic components one by one, and supplies the electronic components at the supply position. The supply unit 110 is not limited to the tape feeder 114, and may be a tray-type supply device that picks up and supplies electronic components from the tray. Further, the supply unit 110 may be configured to include both a tape type and a tray type, or other supply devices.

The mounting portion 112 includes a mounting head (see FIG. 2) 116 and a moving device (see FIG. 2) 118. The mounting head 116 has a suction nozzle (not shown) for sucking and holding electronic components. The suction nozzle sucks and holds electronic components by sucking air by supplying negative pressure from a positive / negative pressure supply device (not shown). Then, when a slight positive pressure is supplied from the positive / negative pressure supply device, the electronic component is separated. Further, the moving device 118 moves the mounting head 116 between the supply position of the electronic component by the tape feeder 114 and the substrate mounted on the base 60. As a result, in the mounting unit 112, the electronic component supplied from the tape feeder 114 is held by the suction nozzle, and the electronic component held by the suction nozzle is mounted on the substrate.

Further, as shown in FIG. 2, the control device 28 includes a controller 120 and a plurality of drive circuits 122. The plurality of drive circuits 122 include the electromagnetic motors 38 and 56, a holding device 62, an elevating device 64, an inkjet head 76, a heater 78, an inkjet head 88, a flattening device 90, an irradiation device 92, a tape feeder 114, and a mounting head 116. It is connected to the mobile device 118. The controller 120 includes a CPU, a ROM, a RAM, and the like, and is mainly a computer, and is connected to a plurality of drive circuits 122. As a result, the operation of the transfer device 20, the first modeling unit 22, the second modeling unit 24, and the mounting unit 26 is controlled by the controller 120.

In the circuit forming apparatus 10, a resin laminate is formed on the substrate (see FIG. 3) 70 by the above-described configuration, and wiring is formed on the upper surface of the resin laminate. Then, a resin laminate is further formed on the resin laminate so that a part of the wiring is exposed, and electronic components are mounted so as to energize a part of the exposed wiring.

Specifically, the substrate 70 is set on the base 60 of the stage 52, and the stage 52 is moved below the second modeling unit 24. Then, in the second modeling unit 24, as shown in FIG. 3, the resin laminate 130 is formed on the substrate 70. The resin laminate 130 is formed by repeatedly ejecting the ultraviolet-curable resin from the inkjet head 88 and irradiating the discharged ultraviolet-curable resin with ultraviolet rays by the irradiation device 92.

Specifically, in the second printing unit 84 of the second modeling unit 24, the inkjet head 88 ejects the ultraviolet curable resin into a thin film on the upper surface of the substrate 70. Subsequently, when the ultraviolet curable resin is discharged in the form of a thin film, the ultraviolet curable resin is flattened by the flattening device 90 so that the film thickness of the ultraviolet curable resin becomes uniform in the cured portion 86. Then, the irradiation device 92 irradiates the thin film ultraviolet curable resin with ultraviolet rays. As a result, a thin-film resin layer 132 is formed on the substrate 70.

Subsequently, the inkjet head 88 ejects the ultraviolet curable resin into a thin film on the thin film resin layer 132. Then, the thin-film ultraviolet-curable resin is flattened by the flattening device 90, and the irradiation device 92 irradiates the ultraviolet-curable resin discharged in the thin-film form with ultraviolet rays, thereby forming the thin-film ultraviolet-curable resin on the thin-film resin layer 132. The thin-film resin layer 132 is laminated. In this way, the ejection of the ultraviolet-curable resin onto the thin-film resin layer 132 and the irradiation of ultraviolet rays are repeated, and the plurality of resin layers 132 are laminated to form the resin laminate 130.

When the resin laminate 130 is formed by the procedure described above, the stage 52 is moved below the first modeling unit 22. Then, in the first printing unit 72 of the first modeling unit 22, the inkjet head 76 linearly ejects the metal ink 134 onto the upper surface of the resin laminate 130 according to the circuit pattern, as shown in FIG. In this description, as shown in FIG. 5, two linear metal inks 134 are ejected in a state of facing each other on a straight line, and three sets of these two linear metal inks 134 are arranged in parallel. , Discharged. That is, six linear metal inks 134 are ejected onto the upper surface of the resin laminate 130. Subsequently, the metal ink 134 discharged onto the upper surface of the resin laminate 130 is heated by the heater 78 in the heating unit 74 of the first modeling unit 22. As a result, the metal ink 134 is fired, and the wiring 136 is formed on the resin laminate 130.

Subsequently, when the wiring 136 is formed on the resin laminate 130, the stage 52 is moved below the second modeling unit 24. Then, in the second modeling unit 24, as shown in FIGS. 6 and 7, a resin laminate 150 is further formed on the resin laminate 130. The resin laminate 150 has a cavity 152 for exposing the end portion of the wiring 136, and is created by substantially the same method as the resin laminate 130.

That is, in the second printing unit 84 of the second modeling unit 24, the inkjet head 88 ejects the ultraviolet curable resin into a thin film on the upper surface of the resin laminate 130. At this time, the inkjet head 88 discharges the ultraviolet curable resin so that a predetermined portion including the ends of the six wirings 136 on the upper surface of the resin laminate 130 is generally exposed in a rectangular shape. Subsequently, when the ultraviolet curable resin is discharged in the form of a thin film, the ultraviolet curable resin discharged in the form of a thin film is flattened by the flattening device 90 in the cured portion 86, and the ultraviolet rays are irradiated by the irradiation device 92. As a result, a thin-film resin layer 154 is formed on the resin laminate 130.

Subsequently, the inkjet head 88 ejects the ultraviolet curable resin into a thin film only on the portion above the thin film resin layer 154. That is, the inkjet head 88 has a thin film of ultraviolet curable resin on the thin film resin layer 154 so that a predetermined portion including the ends of the six wirings 136 on the upper surface of the resin laminate 130 is generally exposed in a rectangular shape. Discharge in the form. Then, the ultraviolet curable resin discharged in the thin film form is flattened by the flattening device 90, and the ultraviolet rays are irradiated by the irradiation device 92, so that the thin film resin layer 154 is laminated on the thin film resin layer 154. Will be done. In this way, the ejection of the ultraviolet curable resin onto the thin film-shaped resin layer 154 excluding the generally rectangular portion on the upper surface of the resin laminate 130 and the irradiation of ultraviolet rays are repeated, and the plurality of resin layers 154 are laminated. As a result, the resin laminate 150 having the cavity 152 is formed.

Then, when the resin laminate 150 having the cavity 152 is formed, the stage 52 is moved below the mounting unit 26. In the mounting unit 26, electronic components are supplied by the tape feeder 114, and the electronic components are held by the suction nozzles of the mounting head 116. As shown in FIGS. 8 and 9, the electronic component 160 is a so-called SMD (abbreviation of Surface Mount Device), and six components extending from a pair of side surfaces of the component body 162 and the component body 162 facing each other. It is composed of the terminal 164 of. Then, the mounting head 116 is moved by the moving device 118, and the electronic component 160 held by the suction nozzle is mounted on the upper surface of the resin laminate 130 inside the cavity 152 of the resin laminate 150. At this time, the electronic component 160 is mounted on the upper surface of the resin laminate 130 so that the six terminals 164 of the electronic component 160 come into contact with the ends of the six wires 136 exposed inside the cavity 152. NS.

As described above, in the circuit forming apparatus 10, the wiring 136 is formed on the upper surface of the resin laminate 130 formed of the ultraviolet curable resin, and the electronic component 160 is mounted on the upper surface of the resin laminate 130 so as to be conductive with the wiring 136. By doing so, a circuit is formed. Further, the resin laminate 150 is formed on the upper surface of the resin laminate 130 with the same raw material as the raw material of the resin laminate 130, that is, the ultraviolet curable resin, and the wiring 136 is covered with the resin laminate 150. As a result, the adhesion between the wiring 136 and the resin laminate 130 is improved to prevent the wiring 136 from peeling off, and the exposure of the wiring 136 is reduced as much as possible to prevent oxidation and ion migration of the wiring 136. Can also be prevented.

However, when the resin laminate 150 is formed on the resin laminate 130, the ultraviolet curable resin is discharged onto the upper surface of the resin laminate 130 except for the end of the wiring, but the resin laminate 130 and the ultraviolet curable Due to the difference between the wettability with the resin and the wettability between the wiring 136 and the ultraviolet curable resin, the entire wiring may be covered with the resin laminate 150. Specifically, when the resin laminate 150 is formed on the resin laminate 130, in the conventional method, as shown in FIG. 7, the ultraviolet curable resin is applied to the cavity 152 on the upper surface of the resin laminate 130. It was discharged so that the edges were straight. That is, although the wiring 136 is formed on the upper surface of the resin laminate 130, the edge of the ultraviolet curable resin covering the resin laminate 130 to the cavity 152 and the edge of the ultraviolet curable resin covering the wiring 136 to the cavity 152 The ultraviolet curable resin was discharged onto the upper surface of the resin laminate 130 so that Then, by irradiating the ultraviolet curable resin with ultraviolet rays, the ultraviolet curable resin is cured to form the resin laminate 150. Ideally, the edge of the resin laminate 150 to the cavity 152 is as shown in FIG. In addition, it is desirable to be linear. However, the wettability of the wiring 136 and the ultraviolet curable resin, that is, the wettability of the ultraviolet curable resin discharged onto the metal wiring 136 is very high. On the other hand, the wettability of the resin laminate 130 and the ultraviolet curable resin, that is, the wettability of the ultraviolet curable resin discharged onto the resin laminate 130 having the same raw material, is the wettability of the wiring 136 and the ultraviolet curable resin. Lower.

Here, wettability indicates the affinity of a liquid on the surface of a solid. The higher the wettability, the better the affinity, and the liquid tends to get wet and spread on the surface of the solid. On the other hand, when the wettability becomes low, the affinity becomes poor, and the liquid becomes difficult to wet and spread on the surface of the solid. In other words, when the wettability becomes high, the angle between the tangent of the outer edge of the droplet dropped on the surface of the solid and the surface of the solid, the so-called contact angle, becomes small, and the liquid becomes a solid. It becomes easy to get wet and spread on the surface of. On the other hand, when the wettability becomes high, the contact angle becomes large, and it becomes difficult for the liquid to get wet and spread on the surface of the solid.

Therefore, the ultraviolet curable resin discharged on the wiring 136 is more likely to get wet and spread than the ultraviolet curable resin discharged on the resin laminate 130, so that it is discharged on the wiring 136 as shown in FIG. The ultraviolet curable resin 170 penetrates into the cavity 152 from the ultraviolet curable resin 170 discharged onto the resin laminate 130. That is, the edge of the UV curable resin 170 covering the wiring 136 to the cavity 152 is a convex portion with respect to the cavity 152, and the edge of the UV curable resin 170 covering the resin laminate 130 to the cavity 152 is relative to the cavity 152. It becomes a recess. In this way, when the ultraviolet curable resin 170 discharged onto the wiring 136 enters the inside of the cavity 152 and becomes a convex portion with respect to the cavity 152, the ultraviolet curable resin 170 discharged onto the wiring 136 becomes a convex portion. There is a risk of covering the entire wiring 136. Then, when the ultraviolet curable resin 170 is cured by irradiation with ultraviolet rays in that state, the resin laminate 150 covers the entire wiring, and the end portion of the wiring 136 is not exposed in the cavity 152. In such a state, even if the electronic component 160 is mounted inside the cavity 152, the terminal 164 of the electronic component 160 cannot be brought into contact with the wiring 136, and the electronic component 160 and the wiring 136 cannot be made conductive. ..

Therefore, in the circuit forming apparatus 10, the ultraviolet curable resin 170 is a resin laminate in consideration of the difference between the wettability of the resin laminate 130 and the ultraviolet curable resin 170 and the wettability of the wiring 136 and the ultraviolet curable resin 170. It is discharged onto 130 and wiring 136. That is, since the wettability of the wiring 136 and the UV curable resin 170 is higher than the wettability of the resin laminate 130 and the UV curable resin 170, the UV curable resin 170 gets wet on the wiring 136 and on the resin laminate 130. Considering the spread, the ultraviolet curable resin 170 is discharged onto the resin laminate and the wiring. Specifically, as shown in FIG. 11, the edge of the UV curable resin 170 covering the wiring 136 to the cavity 152 is separated from the cavity 152 from the edge of the UV curable resin 170 covering the resin laminate 130 to the cavity 152. As described above, the ultraviolet curable resin 170 is discharged. That is, the edge of the UV curable resin 170 covering the wiring 136 to the cavity 152 is a recess with respect to the cavity 152, and the edge of the UV curable resin 170 covering the resin laminate 130 to the cavity 152 is convex with respect to the cavity 152. The ultraviolet curable resin 170 is discharged so as to form a portion. Therefore, the ultraviolet curable resin 170 discharged onto the wiring 136 is dented from the inside of the cavity 152 and becomes a recess with respect to the cavity 152.

Then, the ultraviolet curable resin 170 discharged onto the wiring 136 wets and spreads toward the end of the wiring 136, but does not spread to a position that covers the entire wiring 136 as shown in FIG. That is, since the ultraviolet curable resin 170 discharged onto the wiring 136 is recessed from the inside of the cavity 152, even if the ultraviolet curable resin 170 gets wet and spreads on the wiring 136, it does not reach the end of the wiring 136. .. The ultraviolet curable discharged onto the wiring 136 wets and spreads to the cavity 152 to a position similar to that of the ultraviolet curable resin 170 discharged onto the resin laminate 130. Therefore, the edge of the UV curable resin 170 wet and spread on the wiring 136 to the cavity 152 is located substantially linearly with the edge of the UV curable resin 170 wet and spread on the resin laminate 130 to the cavity 152. do.

Then, by irradiating the wet and spread ultraviolet curable resin 170 with ultraviolet rays in this way, the resin laminate 150 is generated, and the end portion of the wiring 136 is exposed in the cavity 152 of the resin laminate 150. .. As a result, the electronic component 160 is mounted in the cavity 152 so that the terminal 164 comes into contact with the end of the exposed wiring 136, so that a circuit in which the electronic component 160 and the wiring 136 are conducted can be formed. can. As described above, in the circuit forming apparatus 10, the ultraviolet curable resin 170 is more easily wetted and spread on the wiring 136 than on the resin laminate 130, and the ultraviolet curable resin 170 is placed on the resin laminate 130 and the wiring 136. The exposure of the wiring 136 in the cavity 152 is guaranteed by being discharged onto the cavity 152.

Further, as shown in FIG. 2, the controller 120 of the circuit forming apparatus 10 includes a wiring forming portion 180, a resin layer forming portion 182, and a mounting portion 184. The wiring forming portion 180 is a functional portion for forming the wiring 136 on the resin laminate 130. The resin layer forming portion 182 is a functional portion for forming the resin laminated body 150 having the cavity 152 on the resin laminated body 130. The mounting unit 184 is a functional unit for mounting the electronic component 160 inside the cavity 152.

In the above embodiment, the resin laminate 130 is an example of a base material. The metal ink 134 is an example of a conductive fluid. Wiring 136 is an example of wiring. The resin laminate 150 is an example of a resin layer. The cavity 152 is an example of an opening. The electronic component 160 is an example of an electronic component. Terminal 164 is an example of a terminal. The ultraviolet curable resin 170 is an example of a curable resin. The process executed by the wiring forming unit 180 is an example of the wiring forming process. The step executed by the resin layer forming unit 182 is an example of the resin layer forming step. The step executed by the mounting unit 184 is an example of the mounting process.

The present invention is not limited to the above examples, and can be carried out in various modes with various modifications and improvements based on the knowledge of those skilled in the art. For example, in the above embodiment, the wiring is formed on the resin laminate 130, but the wiring may be formed on a base material different from the resin laminate 130, for example, a glass plate. When the wiring is formed on the glass plate in this way, the UV curable resin is a glass plate in consideration of the wettability between the wiring and the UV curable resin and the wettability between the glass plate and the UV curable resin. Discharged on top. Specifically, as shown in FIG. 13, the ultraviolet curable resin 200 is formed on the glass plate 190 so that the wiring 136 is formed on the glass plate 190 and the end portion of the wiring 136 is exposed in the cavity 202. It is discharged. At this time, for example, a case where the wettability between the glass plate 190 and the ultraviolet curable resin 200 is higher than the wettability between the wiring 136 and the ultraviolet curable resin 200 will be described. In such a case, the UV curable resin is such that the edge of the UV curable resin 200 covering the glass plate 190 to the cavity 202 is separated from the cavity 202 from the edge of the UV curable resin 200 covering the wiring 136 to the cavity 202. 200 is discharged. That is, the edge of the UV curable resin 200 covering the glass plate 190 to the cavity 202 is a recess with respect to the cavity 202, and the edge of the UV curable resin 200 covering the wiring 136 to the cavity 202 is a convex portion with respect to the cavity 202. The ultraviolet curable resin 200 is discharged so as to be. Therefore, the ultraviolet curable resin 200 discharged onto the glass plate 190 is dented from the inside of the cavity 202 and becomes a recess with respect to the cavity 202. By discharging the ultraviolet curable resin 200 in this way, as shown in FIG. 14, the ultraviolet curable resin 200 discharged onto the glass plate 190 is discharged onto the wiring 136 with respect to the cavity 202. Wet and spread to the same position as the UV curable resin 200. Therefore, the edge of the UV curable resin 200 wet and spread on the glass plate 190 to the cavity 202 is located substantially in line with the edge of the UV curable resin 200 wet and spread on the wiring 136 to the cavity 202. .. As a result, the cavity 202, which is generally defined by a straight line, can be formed, so that a circuit having a good appearance can be formed.

Further, in the above embodiment, the wiring 136 is formed of the metal ink 134, but the wiring may be formed of the conductive resin paste. The conductive paste is a resin in which micrometer-sized metal particles are dispersed in a resin that is cured by heating. Then, the conductive paste is heated and the resin is cured to shrink, and the metal particles dispersed in the resin come into contact with each other. As a result, the conductive paste becomes a wiring that exhibits conductivity.

130: Resin laminate (base material) 134: Metal ink (conductive fluid) 136: Wiring 150: Resin laminate (resin layer) 152: Cavity (opening) 160: Electronic component 164: Terminal 170: Ultraviolet curing resin (cured) (Resin) 180: Wiring forming part (wiring forming step) 182: Resin layer forming part (resin layer forming step) 184: Mounting part (mounting step)

Claims (3)

A wiring forming process in which a conductive fluid that develops conductivity by heating is applied onto a base material to form wiring, and
A resin layer forming step in which a curable resin is applied onto the base material so that a part of the wiring is exposed, and a resin layer having an opening in which a part of the wiring is exposed is formed on the base material. Including
The resin layer forming step is
When the wettability of the wiring and the curable resin is higher than the wettability of the base material and the curable resin, the edge of the curable resin covering the wiring to the opening covers the base material. This is a step of discharging the curable resin so as to be separated from the opening from the edge of the curable resin to the opening.
When the wettability of the base material and the curable resin is higher than the wettability of the wiring and the curable resin, the edge of the curable resin covering the base material to the opening covers the wiring. A circuit forming method, which is a step of discharging the curable resin so as to be separated from the opening from the edge of the curable resin to the opening. The circuit forming method according to claim 1, wherein the base material is formed of the curable resin. The circuit formation according to claim 1 or 2, which includes a mounting step of mounting the electronic component inside the opening so that the terminal of the electronic component comes into contact with a part of the wiring exposed from the opening. Method.

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