JP7370421B2 - 3D molded circuit parts - Google Patents

Description

The present invention relates to a three-dimensional molded circuit component in which a circuit pattern is formed on a base material including a metal part and a resin part.

In recent years, MIDs (Molded Interconnected Devices) have been put into practical use in smartphones and the like, and their application in the automotive field is expected to expand in the future. MID is a device in which a three-dimensional circuit is formed using a metal film on the surface of a molded body, and can contribute to making products lighter, thinner, and in the number of parts.

MIDs equipped with light emitting diodes (LEDs) have also been proposed. Since LEDs generate heat when energized, it is necessary to exhaust heat from the back side, and it is important to improve the heat dissipation performance of the MID.

Patent Document 1 proposes a composite component that integrates an MID and a metal heat dissipation material. According to Patent Document 1, this composite component achieves both heat dissipation and miniaturization of the MID. On the other hand, the adhesion between metals with high heat dissipation and resin materials is generally low. Patent Document 2 proposes nanomolding technology (NMT) that improves the adhesion between metal and resin materials. In nanomolding technology (NMT), the surface of metal is chemically roughened to create nano-sized irregularities, and then the metal is integrally molded with a resin material. According to Patent Document 2, when nanomolding technology (NMT) is used, the contact area of the bonding interface between the metal and the resin material is significantly expanded, the adhesion is improved, and the bond between the metal and the resin material in the heat shock test is improved. Peeling is suppressed and heat dissipation is also improved. Patent Document 3 proposes an LED heat dissipation lamp manufactured by bonding metal and resin materials using nanomolding technology (NMT).

Patent No. 3443872 Japanese Patent Application Publication No. 2009-6721 Patent No. 5681076

However, in recent years, electronic devices have become more sophisticated and smaller, and the MIDs used therein have also become more dense and highly functional, and higher heat dissipation is required. The present invention solves these problems and provides a three-dimensional molded circuit component that has high heat dissipation, is easy to mold, and has high productivity.

According to a first aspect of the present invention, the three-dimensional molded circuit component includes a base material including a metal part and a resin part containing a filler, and a thermosetting resin formed on the metal part. or a resin thin film containing a photocurable resin, a circuit pattern formed on the resin part and the resin thin film by an electroless plating film, and a circuit pattern mounted on the resin thin film; a mounting component electrically connected to the circuit pattern formed on the resin thin film on a back surface, the resin part has a roughened part on the surface, and the roughened part There is provided a three-dimensional molded circuit component characterized in that the filler is exposed and the circuit pattern is formed in the roughened portion.

In this embodiment, the thickness of the resin thin film may be 0.01 mm to 0.5 mm. In this aspect, the resin thin film may contain an insulating heat dissipating material.

In this aspect, the resin portion may include foam cells. In this aspect, the resin portion may include foam cells, and the resin thin film may not substantially contain foam cells.

In this aspect, the mounted component may be an LED.

In this aspect, a nickel phosphorus film may be formed on the surface of the metal part.

In this aspect, the thickness of the resin portion may be 0.5 mm or more. In this aspect, the area of the resin thin film may be 0.1 cm ² to 25 cm ² for each mounted component placed on the resin thin film.

The present invention provides a three-dimensional molded circuit component that has high heat dissipation properties, is easy to mold, and has high productivity.

FIG. 1 is a schematic cross-sectional view of a three-dimensional molded circuit component manufactured in the first embodiment. FIG. 2 is an enlarged view of the periphery of the mounted component in the schematic cross-sectional view of the three-dimensionally molded circuit component shown in FIG. FIG. 3 is a schematic cross-sectional view of another example of the three-dimensional molded circuit component manufactured in the first embodiment. FIGS. 4A and 4B are schematic cross-sectional views of still another example of the three-dimensional molded circuit component manufactured in the first embodiment. FIG. 5 is a schematic cross-sectional view of a three-dimensionally molded circuit component manufactured in Modification 1 of the first embodiment. FIG. 6 is a schematic cross-sectional view of a three-dimensional molded circuit component manufactured in Modification 2 of the first embodiment. FIG. 7 is a schematic cross-sectional view of a three-dimensional molded circuit component manufactured in the second embodiment.

[First embodiment]
(1) Three-dimensional molded circuit component In this embodiment, a three-dimensional molded circuit component 100 shown in FIG. 1 will be described. The three-dimensional molded circuit component 100 includes a base material 10 including a metal part 11 and a resin part 12, a circuit pattern 14 formed by a plating film on the resin part 12, and a recess 13 formed on the base material 10. It has a mounting component 15 that is mounted on the circuit pattern 14 and electrically connects with the circuit pattern 14. As shown in FIG. 2, the side wall 13a of the recess 13 is formed of the resin part 12, and the bottom 13b of the recess 13 is formed of the resin thin film 16. Mounted component 15 is placed on metal part 11 with resin thin film 16 interposed therebetween. In this embodiment, the resin thin film 16 is a part of the resin part 12. Therefore, the resin thin film 16 is formed of the same resin as the resin portion 12.

The base material 10 can be any composite material in which the metal part 11 and the resin part 12 are joined together, but in this embodiment, the base material 10 is an integrally molded material in which the metal part 11 and the resin part 12 are integrally molded. Use your body. Here, integral molding does not mean gluing or joining separately created parts (secondary adhesion or mechanical joining), but refers to a process that joins each part during molding (typically insert molding). do.

The metal part 11 radiates heat generated by the mounted component 15 mounted on the base material 10. Therefore, it is preferable to use a metal with heat dissipation properties for the metal part 11, and for example, iron, copper, aluminum, titanium, magnesium, stainless steel (SUS), etc. can be used. Among these, magnesium and aluminum are preferably used from the viewpoint of weight reduction, heat dissipation, and cost. These metals may be used alone or in combination of two or more.

The resin portion 12 insulates the circuit pattern 14 formed thereon from the metal portion 11, which is a conductor. The resin portion 12 is preferably made of a heat-resistant, high-melting-point thermoplastic resin that is resistant to solder reflow. For example, aromatic polyamides such as 6T nylon (6TPA), 9T nylon (9TPA), 10T nylon (10TPA), 12T nylon (12TPA), MXD6 nylon (MXDPA), alloy materials thereof, polyphenylene sulfide (PPS), and liquid crystal polymers. (LCP), polyetheretherketone (PEEK), polyetherimide (PEI), etc. can be used. These thermoplastic resins may be used alone or in combination of two or more. Further, in this embodiment, the resin thin film 16 on which the mounting component 15 is mounted by soldering is a part of the resin portion 12. For this reason, the resin used for the resin part 12 preferably has a melting point of 260°C or higher, more preferably 290°C or higher, so that soldering is possible. Note that this does not apply when low-temperature solder is used to mount the mounted component 15. Moreover, from the viewpoint of improving dimensional stability and rigidity, these thermoplastic resins may contain inorganic fillers such as glass fillers and mineral fillers.

The shape and size of the metal part 11 and the resin part 12 can be any shape and size depending on the use of the three-dimensionally molded circuit component 100. Since the circuit pattern 14 is three-dimensionally formed on the resin part 12, the resin part 12 has a plurality of surfaces or a three-dimensional surface including a spherical surface or the like. In this embodiment, as shown in FIG. 1, a resin part 12 which is a thermoplastic resin layer is integrally formed on a metal part 11 which is a bent metal plate. Thereby, the thermoplastic resin layer (resin part 12) is bent along the bent metal plate (metal part 11) and has a plurality of surfaces. The thickness t ₁₁ of the metal plate (metal part 11) is, for example, 0.5 mm or more, preferably 1 mm or more, from the viewpoint of heat dissipation, while reducing weight and cost and improving workability. From this point of view, the length is, for example, 20 mm or less, preferably 10 mm or less. Here, the thickness t ₁₁ of the metal plate (metal portion 11 ) is the thickness in the direction perpendicular to the interface with the resin portion 12 . The thickness t ₁₂ of the thermoplastic resin layer (resin part 12) is, for example, 0.5 mm or more, preferably 1 mm or more, from the viewpoint of ease of molding, while, from the viewpoint of cost, it is, for example, 5 mm or less. It is preferable that the diameter is 3 mm or less. Here, the thickness _t12 of the thermoplastic resin layer (resin part 12) is the thickness of the part other than the recess 13 where the mounted component 15 is mounted, and the thickness in the direction perpendicular to the interface with the metal part 11. It is. Further, since the thermoplastic resin layer (resin part 12) is provided for insulating the circuit pattern 14 and the metal part 11, the thermoplastic resin layer (resin part 12) is provided in the part where the circuit pattern 14 is not formed. It does not need to be provided.

In addition, in this embodiment, the metal part 11 is not limited to a metal plate, but it is also possible to use a complex-shaped metal molded by die-casting.

Since the circuit pattern 14 is formed on the resin part 12 which is an insulator, it is preferably formed by electroless plating. Therefore, the circuit pattern 14 may include, for example, an electroless plating film such as an electroless nickel phosphorus plating film, an electroless copper plating film, an electroless nickel plating film, etc. Among them, the circuit pattern 14 may include an electroless nickel phosphorus plating film. preferable. When the circuit pattern 14 is formed using an electroless nickel phosphorus plating film, a nickel phosphorus film (electroless nickel phosphorus plating film) 18 can be formed on the surface of the metal part 11 at the same time, and the corrosion resistance of the metal part 11 can be improved. In the circuit pattern 14, another type of electroless plating film or electrolytic plating film may be further laminated on the electroless plating film. By increasing the total thickness of the plating film, the electrical resistance of the circuit pattern 14 can be reduced. From the viewpoint of lowering electrical resistance, the plating film laminated on the electroless plating film is preferably an electroless copper plating film, an electrolytic copper plating film, an electrolytic nickel plating film, or the like. Furthermore, a plating film of tin, gold, silver, or the like may be formed on the outermost surface of the circuit pattern 14 in order to improve the solder wettability of the plating film so as to be compatible with solder reflow.

The circuit pattern 14 is three-dimensionally formed over a plurality of surfaces of the resin portion 12 or along a three-dimensional surface including a spherical surface or the like. The circuit pattern 14 is a three-dimensional electrical circuit that is three-dimensionally formed over a plurality of surfaces of the resin portion 12 or along a three-dimensional surface including a spherical surface and has conductivity. The circuit pattern 14 may be formed on the side wall 13a and bottom 13b of the recess 13 in order to electrically connect with the mounted component 15 mounted in the recess 13.

The mounted component 15 is electrically connected to the circuit pattern 14 by solder 17, and generates heat when energized, thereby becoming a heat generation source. Examples of the mounted components 15 include LEDs (light emitting diodes), power modules, ICs (integrated circuits), thermal resistors, and the like. In this embodiment, an LED is used as the mounting component 15. The three-dimensionally molded circuit component 100 of this embodiment can efficiently dissipate the heat generated by the LED, even when an LED with a large amount of heat is used as a mounted component. Further, the LED generates heat from the back surface opposite to the light emitting surface. The three-dimensional molded circuit component 100 of this embodiment can efficiently radiate heat generated by the LED by arranging the metal part 11 serving as a heat radiating member on the back side of the LED (mounted component 15).

The mounting component 15 is mounted in the recess 13 formed on the base material 10. One mounting component 15 may be mounted in one recess 13, or a plurality of mounting components 15 may be mounted. The side wall 13a of the recess 13 is formed of the resin part 12, and the bottom 13b of the recess 13 is formed of the resin thin film 16. Mounted component 15 is placed on metal part 11 with resin thin film 16 interposed therebetween. In this embodiment, the resin thin film 16 is a part of the resin part 12. That is, in this embodiment, the recess 13 is formed in the thermoplastic resin layer (resin portion 12), and the resin thin film 16 is a thin portion of the thermoplastic resin layer. Therefore, the resin thin film 16 is formed of the same thermoplastic resin as the resin portion 12. In this embodiment, the metal part 11 and the resin part 12 including the resin thin film 16 constitute the base material 10 .

From the viewpoint of heat dissipation, it is desirable to place the mounted component 15 directly on the metal part 11, but since the mounted component 15 and the metal part 11 need to be insulated, direct mounting is difficult. In this embodiment, by arranging the mounted component 15 on the metal part 11 via the thin resin film 16, both insulation and heat dissipation between the mounted component 15 and the metal part 11 are achieved.

The thickness t ₁₆ of the resin thin film 16 is 0.01 mm to 0.5 mm. Since the resin material has heat insulating properties, if the thickness _t16 of the resin thin film 16 is approximately 1 to 5 mm, which is the thickness of a typical injection molded product, the heat dissipation property will be insufficient. By setting the thickness t ₁₆ of the resin thin film 16 to 0.5 mm or less, the heat generated by the mounted component 15 can be sufficiently dissipated by the metal part 11 . Further, since the mounted component 15 is electrically connected to the circuit pattern 14, wiring may be formed on the resin thin film 16 using a plating film. Although the details will be described later, since laser drawing is used to form the wiring made of the plating film, the resin thin film 16 needs to have a thickness that will not be penetrated by the laser drawing. Furthermore, since the resin thin film 16 of this embodiment is molded, for example, by insert molding, etc., it needs to have a thickness that allows the molten resin to flow. If the thickness t ₁₆ of the resin thin film 16 is 0.01 mm or more, it is possible to form wiring on the resin thin film 16 using laser drawing, and it is also possible to mold the resin thin film 16 using insert molding. Become. From the viewpoint explained above, the thickness t ₁₆ of the resin thin film 16 is further preferably 0.1 mm to 0.2 mm.

In addition, when the thickness _t16 of the resin thin film 16 is not constant, the average value (average thickness) of the thickness of the resin thin film 16 is 0.01 mm to 0.5 mm, preferably 0.1 mm to 0.5 mm. It is 2mm. The average value (average thickness) of the thickness of the resin thin film 16 is determined by measuring the thickness of the resin thin film 16 at three points in the cross section of the resin thin film 16 in the direction perpendicular to the interface between the resin thin film 16 and the metal part 11, for example. , or more, and can be determined as the average value of the measured values. Further, even if the thickness t ₁₆ of the resin thin film 16 is not constant, it is preferable that the thickness t ₁₆ of the resin thin film 16 varies within a range of 0.01 mm to 0.5 mm, and 0.01 mm to 0.5 mm. More preferably, it varies within a range of 1 mm to 0.2 mm. That is, the resin thin film 16 may be a region in which the thickness t ₁₆ is in the range of 0.1 mm to 0.2 mm, preferably in the range of 0.1 mm to 0.2 mm.

The area of the resin thin film 16, ie, the area of the bottom 13b of the recess 13, is preferably 0.1 cm ² to 25 cm ² per mounting component 15 placed on the resin thin film 16. The wider the area of the resin thin film 16, the higher the heat dissipation effect, but the more difficult it is to mold. If the area of the resin thin film 16 is within the above range, both high heat dissipation effect and ease of molding can be achieved. In this embodiment, the thin resin film 16 with high heat dissipation is limited to the portion where the mounted component 15 is mounted. This minimizes the thin film portion that is difficult to mold, increases the ease of molding, and, as a result, increases the productivity of three-dimensionally molded circuit components.

In this embodiment, the area of the resin thin film 16 is, for example, the area of a region _S16 having a thickness _t16 that is thinner than the thickness _t12 of the surrounding resin part 12, as shown in FIG. This is the area of the bottom 13b. Note that the region _S16 is not limited to the region in which the mounted component 15 is in contact, but may be a wider region than the region S15 in contact with the mounted component ₁₅ , as shown in FIG.

The recess 13 can be used as a recess for positioning the mounting position of the mounted component 15. In a three-dimensional circuit (three-dimensional circuit), the mounting position of a mounted component must be determined in three directions, and it is more difficult to determine the mounting position than in a two-dimensional circuit (planar circuit). In the three-dimensionally molded circuit component 100 of this embodiment, the mounting position of the mounting component 15 is made into a recess, so that the mounting position can be easily detected. When using the recess 13 as a recess for positioning the mounted component 15, for example, as shown in FIG. It is preferable that the shape and area of the mounting component 15 are substantially the same as the shape and area of the surface of the mounting component 15 that contacts the bottom 13b. In this case, as shown in FIG. 3, the area of the resin thin film 16 (the area of the region _S16 ) is approximately the same as the area of the region _S15 with which the mounted component 15 is in contact. This further facilitates positioning of the mounting position of the mounted component 15. From the viewpoint of facilitating positioning of the mounting position of the mounting component 15, the depth _d13 of the recess 13 is preferably 0.1 mm to 5 mm.

A nickel phosphorus film 18 may be formed on the surface of the metal part 11 in this embodiment. Since the nickel phosphorus film 18 has high corrosion resistance, the corrosion resistance of the metal part 11 can be improved.

(2) Method for manufacturing three-dimensionally molded circuit component A method for manufacturing the three-dimensionally molded circuit component 100 will be described. First, a base material 10 including a metal part 11 and a resin part 12 is manufactured. In this embodiment, the base material 10 is manufactured by insert molding (integral molding) in which the resin part 12 is formed by injection filling a thermoplastic resin into a mold in which the metal part 11 is placed first. In order to improve the adhesion between the metal part 11 and the resin part 12, for example, nanomolding technology (NMT) disclosed in Patent Document 2 or 3 may be used. Further, as another method for improving the adhesion between the metal part 11 and the resin part 12, the surface shapes of the metal part 11 and the resin part 12 may be shaped so that they do not physically separate.

In this embodiment, the resin thin film 16 is a part of the resin part 12, and the recess 13 is formed on the surface of the resin part 12. Therefore, in this embodiment, the resin part 12 including the resin thin film 16 is molded using a mold in which a convex part corresponding to the concave part 13 is formed in the cavity.

Next, a circuit pattern 14 made of a plating film is formed on the resin part 12. The method for forming the circuit pattern 14 is not particularly limited, and a general-purpose method can be used. For example, the plating film is patterned with photoresist and then etched to remove the plating film in areas other than the circuit pattern, the area where the circuit pattern is to be formed is irradiated with laser light to roughen the base material, or the functional group is removed. Examples include a method in which a plating film is formed only on the portion irradiated with laser light.

In this embodiment, the circuit pattern 14 is formed by the method described below. First, a catalytic activity blocking layer is formed on the surface of the resin portion 12. Next, on the surface of the resin portion 12 on which the catalytic activity blocking layer is formed, a portion where the electroless plating film is to be formed, that is, a portion where the circuit pattern 14 is to be formed, is drawn by laser. An electroless plating catalyst is applied to the laser-drawn surface of the resin portion 12, and then an electroless plating solution is brought into contact with the surface. In this method, the catalytic activity-hindering layer impedes (hinders) the catalytic activity of the electroless plating catalyst applied thereon. Therefore, the formation of an electroless plating film on the catalyst activity blocking layer is suppressed. On the other hand, since the interfering layer is removed from the laser-drawn portion, an electroless plating film is generated. Thereby, the circuit pattern 14 can be formed on the surface of the resin portion 12 using an electroless plating film.

The catalyst activity blocking layer preferably contains, for example, a polymer having at least one of an amide group and an amino group (hereinafter appropriately referred to as "amide group/amino group-containing polymer"). The amide group/amino group-containing polymer acts as a catalytic activity inhibitor that prevents (hinders) or reduces the catalytic activity of the electroless plating catalyst. Although the mechanism by which the amide group/amino group-containing polymer inhibits the catalytic activity of the electroless plating catalyst is not clear, the amide group and amino group adsorb, coordinate, react, etc. with the electroless plating catalyst, and as a result, the electroless plating It is assumed that the plating catalyst becomes unable to act as a catalyst.

Any amide group/amino group-containing polymer can be used, but from the viewpoint of inhibiting the catalytic activity of the electroless plating catalyst, a polymer having an amide group is preferable, and a branched polymer having a side chain is preferable. . In the branched polymer, the side chain preferably contains at least one of an amide group and an amino group, and more preferably the side chain contains an amide group. Preferably, the branched polymer is a dendritic polymer. Dendritic polymers are polymers that have a molecular structure that frequently repeats regular branches, and are classified into dendrimers and hyperbranched polymers. Dendrimers are spherical polymers with a diameter of several nanometers that have an orderly and completely dendritic structure centered on a core molecule. Hyperbranched polymers, unlike dendrimers that have a completely dendritic structure, It is a polymer with complete dendritic branching. Among dendritic polymers, hyperbranched polymers are preferable as the branched polymers of this embodiment because they are relatively easy to synthesize and inexpensive.

The laser light and electroless plating catalyst used for laser drawing are not particularly limited, and general-purpose ones can be appropriately selected and used.

The electroless plating solution is not particularly limited, and a general-purpose solution can be appropriately selected and used, but a neutral electroless nickel phosphorus plating solution is preferred for the reasons explained below. Here, the "neutral" electroless nickel phosphorous plating solution refers to an electroless nickel phosphorous plating solution having a pH of 5.5 to 7.0, for example. According to studies conducted by the present inventors, it has been found that the metal portion 11 may be eroded by the electroless plating solution and corrode depending on the type of metal used. For example, if an alkaline electroless copper plating solution is used, corrosion will not occur if magnesium is used for the metal part 11, but corrosion will occur if aluminum is used. On the other hand, if a neutral electroless nickel phosphorus plating solution is used, corrosion of aluminum can be suppressed. Therefore, by using the electroless nickel phosphorus plating solution, the range of metal selection for the metal part 11 is expanded, and for example, aluminum, which is cheaper than magnesium, can be used for the metal part 11. Furthermore, from the viewpoint of increasing plating reactivity, a weakly acidic electroless nickel phosphorus plating solution having a pH of about 4.0 to 5.5 may be used. In this case, the growth rate of the nickel phosphorus plating film on the aluminum surface is faster than the rate of corrosion of aluminum by the acidic solution, so the plating film can be coated without damaging the aluminum. It is known that the corrosion resistance of aluminum can be improved by anodic oxidation (alumite treatment), which forms an oxide film on the surface, but alumite treatment increases costs. In this embodiment, by using an electroless nickel phosphorus plating solution to form the circuit pattern 14, the nickel phosphorus film 18 can be formed on the surface of aluminum at the same time as the circuit pattern 14 is formed, and the metal part 11 corrosion resistance can be improved.

In forming the circuit pattern 14, other types of electroless plating films or electrolytic plating films may be further laminated on the electroless plating film. At this time, if the nickel phosphorus film 18 is formed on the surface of the metal part 11, corrosion of the metal part 11 by other electroless plating solution or electrolytic plating solution can be suppressed.

After forming the circuit pattern 14 on the resin part 12, the mounting component 15 is mounted in the recess 13 formed on the base material 10 and electrically connected to the circuit pattern 14. Thereby, the three-dimensional molded circuit component 100 of this embodiment is obtained. The mounting method is not particularly limited, and a general-purpose method can be used, such as a solder reflow method in which the mounted component 15 is passed through the base material 10 in a high-temperature reflow oven, or a laser beam is applied to the base material 10 and the mounted component. The mounted component 15 may be soldered to the base material 10 by a laser soldering method (spot mounting) in which the interface of the laser beam 15 is irradiated and soldered.

In addition, in the three-dimensional molded circuit component 100 of the present embodiment described above, the mounting component 15 is mounted in the recess 13 formed on the base material 10, but the present embodiment is not limited to this. For example, as shown in FIGS. 4(a) and 4(b), if the mounted component 15 is placed on the metal part 11 via a resin thin film 16 with a thickness of 0.01 mm to 0.5 mm, The component 15 does not necessarily have to be mounted in the recess. Even if the mounted component 15 is not mounted in the recessed portion, by mounting it on the resin thin film 16, the heat generated by the mounted component 15 can be sufficiently dissipated by the metal portion 11.

[Modification 1]
Next, a first modification of the present embodiment shown in FIG. 5 will be described. In the three-dimensional molded circuit component 100 shown in FIG. use The configuration of the three-dimensionally molded circuit component 200 is the same as that of the three-dimensionally molded circuit component 100, except that the metal portion 21 uses a radiation fin. The three-dimensionally molded circuit component 200 can be manufactured by the same method as the three-dimensionally molded circuit component 100, except that a radiation fin is used for the metal part 21. In the three-dimensional molded circuit component 200, the heat radiation effect can be further enhanced by using heat radiation fins in the metal portion 21.

[Modification 2]
Next, a second modification of the present embodiment shown in FIG. 6 will be described. In the three-dimensionally molded circuit component 300 of Modification 2 shown in FIG. 6, the resin portion 32 includes foam cells 39. On the other hand, the resin thin film 36 does not substantially contain foam cells. Here, the resin thin film 36 "substantially does not contain foamed cells" means that the resin thin film 36 does not contain any foamed cells at all, and also means that the resin thin film 36 has good heat dissipation properties and is not adversely affected during reflow. This includes cases where a small amount of foam cells are included. That is, even if the resin thin film 36 contains foamed cells, the amount thereof is small, and the density of the foamed cells contained in the resin thin film 36 is higher than that of the foamed cells 39 contained in the resin portion 32 in the portion other than the resin thin film 36. lower than density. The configuration of the three-dimensionally molded circuit component 300 other than the resin portion 32 is the same as that of the three-dimensionally molded circuit component 100.

In the three-dimensional molded circuit component 300 of this modification, the resin portion 32 has the foamed cells 39, so that the weight of the entire component can be reduced and the dimensional accuracy can be improved. On the other hand, since the resin thin film 36 does not substantially include the foamed cells 39, the heat dissipation properties of the resin thin film 36 are maintained.

A method for manufacturing the three-dimensional molded circuit component 300 of this modification will be described. First, the base material 30 including the metal part 11 and the resin part 32 is manufactured by integral molding. At this time, the resin portion 32 is foam-molded. The resin portion 32 is preferably foam-molded using a physical foaming agent such as carbon dioxide or nitrogen. Types of foaming agents include chemical foaming agents and physical foaming agents, but chemical foaming agents have a low decomposition temperature, making it difficult to foam resin materials with high melting points. It is preferable to use a resin with a high melting point and high heat resistance for the resin portion 32. If a physical foaming agent is used, the resin portion 32 can be foam-molded using a high melting point resin. Molding methods using physical foaming agents include MuCell (registered trademark) using supercritical fluid, and the low-pressure foam molding method proposed by the present inventors that does not require high-pressure equipment (for example, as described in WO2013/027615). ) can be used.

In this modification, in molding the resin portion 32, the viscosity of the molten resin decreases due to dissolution of the physical foaming agent. This promotes the flow of the molten resin in a narrow area corresponding to the resin thin film 36 in the mold cavity, making it easier to mold the resin thin film 36. Furthermore, in the narrow region corresponding to the resin thin film 36 inside the mold cavity, the solidification rate of the molten resin is fast, making it difficult for foam cells to grow. As a result, foam cells 39 are substantially less likely to be formed in the resin thin film 36 . From the viewpoint of suppressing the formation of foam cells within the resin thin film 36, the thickness _t36 of the resin thin film 36 is preferably 0.01 mm to 0.3 mm, more preferably 0.01 mm to 0.2 mm, and 0.01 mm to 0.3 mm, more preferably 0.01 mm to 0.2 mm. 01 mm to 0.1 mm is even more preferred.

Next, a circuit pattern 14 made of a plating film is formed on the resin portion 32 by a method similar to that of the three-dimensional molded circuit component 100 described above. After forming the circuit pattern 14, the mounting component 15 is mounted in the recess 33 formed on the base material 30 and electrically connected to the circuit pattern 14. Thereby, a three-dimensional molded circuit component 300 of this modification is obtained. In this modification, it is preferable to mount the component 15 by laser soldering (spot mounting). For example, when mounting the component 15 by the solder reflow method, the base material 30 needs to be passed through a reflow oven at a temperature of 230 to 240° C. or higher. At this time, even if a thermoplastic resin having a melting point higher than the reflow temperature is used for the resin part 32, the surface of the resin part 32, which is a foamed molded product, may swell due to expansion of internal moisture. On the other hand, laser soldering (spot mounting) can minimize the range of high temperatures. Since the portion to be irradiated with the laser beam is a resin thin film 36 substantially free of foam cells, the surface is unlikely to swell even when heated by the laser beam.

[Second embodiment]
(1) Three-dimensional molded circuit component In this embodiment, a three-dimensional molded circuit component 400 shown in FIG. 7 will be described. The three-dimensional molded circuit component 400 includes a base material 40 including a metal part 41 and a resin part 42, a circuit pattern 14 formed by a plating film on the resin part 42, and a concave part 43 formed on the base material 40. It has a mounted component 15 that is mounted and electrically connected to the circuit pattern 14. The side wall 43a of the recess 43 is formed of the resin part 42, and the bottom 43b of the recess 43 is formed of the resin thin film 46. The mounted component 15 is placed on the metal part 41 with the resin thin film 46 in between. In the first embodiment, as shown in FIG. 1, the resin thin film 16 is a part of the resin part 12 and is made of thermoplastic resin. On the other hand, in this embodiment, as shown in FIG. 7, the resin thin film 46 is not a part of the resin part 42, but is formed of thermosetting resin or photocuring resin.

As the base material 40, any material can be used as long as it is a composite body in which a metal part 41 and a resin part 42 are joined together, as in the first embodiment. Further, in the first embodiment, an integrally molded body in which the metal part 11 and the resin part 12 are integrally molded is used, but the present embodiment is not limited to this. For example, a base material 40 in which a metal part 41 and a resin part 42 are joined by a joining technique using a triazinethiol derivative may be used.

As the materials for the metal part 41 and the resin part 42, the same materials as in the first embodiment can be used. In this embodiment, a metal block is used as the metal part 41. Further, in the first embodiment, since the resin thin film 16 is a part of the resin part 12, a thermoplastic resin with high heat resistance is used for the resin part 12, but this embodiment is not limited to this. In this embodiment, since the resin thin film 46 and the resin part 42 are formed of different resins, the resin thin film 46 is formed of a resin with high heat resistance, and the resin part 42 is formed of a relatively inexpensive resin with low heat resistance. can. Thereby, the overall cost of the three-dimensional molded circuit component 400 can be reduced. For example, when the mounting component 15 is not mounted on the base material 40 by solder reflow, the resin part 42 is not required to have solder reflow resistance, so general-purpose engineering plastics such as ABS resin, polycarbonate (PC), or a polymer alloy of ABS resin and PC are used. ABS/PC) etc. can be used. These thermoplastic resins may be used alone or in combination of two or more. Moreover, the resin part 42 of this embodiment may have foam cells inside, similarly to the resin part 32 of the second modification of the first embodiment shown in FIG. By having foam cells inside, the weight of the three-dimensional molded circuit component 400 can be reduced.

The circuit pattern 14 and the mounting component 15 may be the same as those in the first embodiment. The mounting component 15 is mounted in a recess 43 formed on the base material 40. The area of the bottom 43b of the recess 43 and the depth of the recess 43 are the same as those of the recess 13 of the first embodiment.

The resin thin film 46 of this embodiment is formed of thermosetting resin or photocuring resin. Since the thermosetting resin and photocuring resin have low viscosity before curing, it is easy to make the resin thin film 46 thin. Further, the thermosetting resin and photocuring resin after curing have high heat resistance and high density, and are suitable as materials for forming the bottom 43b of the recess 43 to which the mounted component 15 is soldered. The resin forming the resin thin film 46 preferably has a melting point of 260°C or higher, more preferably 290°C or higher. As the thermosetting resin, for example, a heat-resistant resin such as epoxy resin, silicone resin, or polyimide resin can be used, and as the photocuring resin, for example, polyimide resin, epoxy resin, etc. can be used. These thermosetting resins may be used alone or in combination of two or more types. Similarly, these photocurable resins may be used alone or in combination of two or more types.

The resin thin film 46 may contain an insulating heat dissipating material. Since the circuit pattern 14 is formed on the resin thin film 46, an inexpensive conductive heat dissipating material such as carbon cannot be used. Although the insulating heat dissipation material is expensive, by including it only in the resin thin film 46 on which the mounted component 15 is mounted, it is possible to both suppress cost increases and improve heat dissipation. Examples of the insulating heat dissipating material include ceramic powders such as aluminum oxide, boron nitride, and aluminum nitride, which are inorganic powders with high thermal conductivity. The resin thin film 46 preferably contains the insulating heat dissipating material in an amount of 10% to 90% by weight, more preferably 30% to 80% by weight.

The thickness t ₄₆ of the resin thin film 46 of this embodiment is preferably 0.01 mm to 0.5 mm. If the thickness t ₄₆ of the resin thin film 46 existing between the mounted component 15 and the metal part 41 is within this range, the heat generated by the mounted component 15 can be sufficiently dissipated by the metal part 41, and the heat generated by the mounted component 15 can be sufficiently radiated onto the resin thin film 46. Laser drawing is also possible. From the viewpoint explained above, the thickness t ₄₆ of the resin thin film 46 is preferably 0.01 mm to 0.1 mm, more preferably 0.03 mm to 0.05 mm.

(2) Method for manufacturing three-dimensionally molded circuit component A method for manufacturing three-dimensionally molded circuit component 400 will be described. First, a resin thin film 46 made of a thermosetting resin or a photocurable resin is formed on the surface 41a of the metal part 41 (metal block) of the base material 40. The resin thin film 46 can be formed, for example, by dissolving a thermosetting resin or a photocurable resin in a solvent to obtain a resin solution, applying the resin solution to the surface 41a of the metal part 41, drying it, and then heating or irradiating it with light. It can be formed by Since the resin solution has a low viscosity, it is easy to form a thin film.

Next, the base material 40 is manufactured by joining the metal part 41 on which the resin thin film 46 is formed and the resin part 42. The method of joining the metal part 41 and the resin part 42 is not particularly limited, and any method can be used. For example, similarly to the first embodiment, it may be integrally molded by insert molding or the like.

In manufacturing the base material 40, a side wall 43a is formed around the resin thin film 46 using the resin portion 42. As a result, a recess 43 defined by the side wall 43a and the bottom 43b is formed on the surface of the base material 40.

Next, a circuit pattern 14 made of a plating film is formed on the resin part 42. As a method for forming the circuit pattern 14, the same method as in the first embodiment can be used.

After forming the circuit pattern 14 on the resin part 42, the mounting component 15 is mounted in the recess 43 formed on the base material 40 and electrically connected to the circuit pattern 14. Thereby, the three-dimensional molded circuit component 400 of this embodiment is obtained. The mounting method is not particularly limited, and as in the first embodiment, a general-purpose method can be used, but in this embodiment, a laser soldering method or a local heating method using a spot heater (spot mounting) can be used. is preferred. In the laser soldering method or the local heating method using a spot heater, only the resin thin film 46 is heated, so a relatively inexpensive resin with low heat resistance can be used for the resin part 42, and the entire three-dimensional molded circuit component 400 is heated. Cost reduction can be achieved.

In addition, in the three-dimensional molded circuit component 400 of the present embodiment described above, the mounting component 15 is mounted in the recess 43 formed on the base material 40, but the present embodiment is not limited to this. For example, as in the first embodiment described above, if the mounted component 15 is mounted on the resin thin film 46, the mounted component 15 does not necessarily have to be mounted in the recess. By mounting the mounted component 15 on the resin thin film 46 without mounting it in the recess, the heat generated by the mounted component 15 can be sufficiently dissipated by the metal part 41.

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited by the Examples and Comparative Examples.

[Example 1]
In this example, a three-dimensional molded circuit component 100 is manufactured using a base material 10 shown in FIG. did. Further, as the mounting component 15, an LED (light emitting diode) was used.

(1) Manufacture of base material The base material 10 was manufactured by insert molding using an aluminum plate for the metal part 11 and an inorganic filler-containing aromatic polyamide (manufactured by Toyobo, Vyroamide GP2X-5, melting point 310°C) for the resin part 12.

A mold having a cavity corresponding to the base material 10, which is a bent plate-shaped body shown in FIG. 1, was prepared. The thickness of the cavity corresponding to the thickness _t10 of the base material 10 was 2 mm. In the cavity of the mold, the shape of the portion corresponding to the concave portion 13 (the convex portion within the cavity) can be changed using a nest so that the thickness _t16 and area of the resin thin film 16 can be varied.

An aluminum plate with a thickness of 1 mm was bent to match the shape of the mold cavity. In order to improve the adhesion between the metal part 11 and the resin part 12 using nanomolding technology (NMT), the surface of the bent aluminum plate was etched. The etched aluminum plate was placed at an appropriate position in the cavity of the mold, and aromatic polyamide was injected into the empty space in the cavity to perform insert molding. For insert molding, a general-purpose injection molding device was used, and the mold temperature was 140°C and the resin temperature was 340°C. In the obtained base material 10, the thickness _t11 of the metal part 11 (metal plate) was 1 mm, and the thickness _t12 of the resin part 12 (thermoplastic resin layer) was 1 mm. Further, by adjusting the size of the nest in the mold cavity, the thickness t ₁₆ of the resin thin film 16 was set to 0.2 mm, and the area was set to 0.49 cm ² (0.7 cm x 0.7 cm). The depth _d13 of the recess 13 was 1.8 mm.

(2) Formation of circuit pattern In this example, the circuit pattern 14 formed of a plating film was formed on the resin part 12 by the method described below.

(a) Synthesis of catalyst activity inhibitor An amide group was introduced into a commercially available hyperbranched polymer (Hypertech HPS-200, manufactured by Nissan Chemical Industries, Ltd.) represented by formula (1), and A hyperbranched polymer was synthesized.

First, a hyperbranched polymer represented by formula (1) (1.3 g, dithiocarbamate group: 4.9 mmol), N-isopropylacrylamide (NIPAM) (1.10 g, 9.8 mmol), α,α'-azo Bisisobutyronitrile (AIBN) (81 mg, 0
．． 49 mmol) and dehydrated tetrahydrofuran (THF) (10 mL) were added to a Schlenk tube, and freeze-degassed three times. Thereafter, the reaction mixture was stirred overnight (18 hours) at 70° C. using an oil bath, and after the reaction was completed, it was cooled with ice water and diluted appropriately with THF. Next, it was reprecipitated in hexane, and the resulting solid product was vacuum dried at 60° C. overnight. NMR (nuclear magnetic resonance) and IR (infrared absorption spectrum) measurements of the product were performed. As a result, it was confirmed that an amide group was introduced into the commercially available hyperbranched polymer represented by formula (1) to produce a polymer represented by formula (2). Next, the molecular weight of the product was measured by GPC (gel permeation chromatography). The molecular weight is number average molecular weight (Mn) = 9,946,
The weight average molecular weight (Mw) was 24,792, and the number average molecular weight (Mn) and weight average molecular weight (Mw), which are unique to the hyperbranched structure, were significantly different values. The yield of the hyperbranched polymer represented by formula (2) was 92%.

(b) Formation of catalyst activity blocking layer The synthesized polymer represented by formula (2) was dissolved in methyl ethyl ketone to prepare a polymer solution with a polymer concentration of 0.5% by weight. The molded base material 10 was dipped in the prepared polymer solution at room temperature for 5 seconds, and then dried in a dryer at 85° C. for 5 minutes. As a result, a catalytic activity blocking layer was formed on the surface of the base material 10. The thickness of the catalyst activity blocking layer was approximately 70 nm.

(c) Laser drawing A 3D laser marker (manufactured by Keyence, fiber laser, output 50W) is used to draw the circuit pattern 14 on the surface of the resin part 12 on which the catalytic activity blocking layer is formed at a processing speed of 2000 mm/s. The parts were laser-drawn. The line width of the drawn pattern was 0.3 mm, and the minimum distance between adjacent drawn lines was 0.5 mm. By laser drawing, the catalyst activity blocking layer in the laser drawn area could be removed. Further, the laser-drawn portion was roughened, and the filler contained in the resin portion 12 was exposed.

(d) Application of electroless plating catalyst and formation of plated film The base material 10 on which laser drawing was performed was immersed in a palladium chloride solution (manufactured by Okuno Pharmaceutical Industries, Ltd., Activator) at 30°C for 5 minutes, and an electroless plating catalyst was applied. . The base material 10 was washed with water, and then the base material 10 was immersed in an electroless nickel phosphorus plating solution (manufactured by Okuno Pharmaceutical Industries, Ltd., Top Nikolon LPH-L, pH 6.5) at 60° C. for 10 minutes. A nickel phosphorus film (electroless nickel phosphorus plating film) was selectively grown to a thickness of about 1 μm on the laser-drawn portion on the resin portion 12. At the same time, a nickel phosphorous film 18 of approximately 1 μm was formed on the surface of the metal portion 11 (aluminum plate).

On the nickel phosphorus film in the laser drawing area, a 10 μm electrolytic copper plating film, a 1 μm electrolytic nickel plating film, and a 0.1 μm electrolytic gold plating film were further laminated in this order using a general-purpose method to form a circuit pattern 14. . In this example, the circuit pattern 14 was formed on the resin thin film 16 without any disconnection.

(3) Mounting of mounted components Solder 17 and mounted components (LED) 15 were placed in the recess 13 formed on the base material 10. Furthermore, solder and resistors (not shown) were placed on the base material 10 in a portion other than the recess 13. The mounted component 15 and a resistor (not shown) were placed at a position where they could be electrically connected to the circuit pattern 14. Next, the base material 10 was passed through a reflow oven. The base material 10 was heated in the reflow oven, and the maximum temperature of the base material 10 was approximately 240° C., and the time period during which the base material 10 was heated at the maximum temperature was approximately 30 seconds. The mounting component 15 was mounted on the base material 10 with the solder 17 to obtain the three-dimensional molded circuit component 100 of this example.

[Example 2]
In this example, the three-dimensional molded circuit component 100 shown in FIG. 1 was manufactured in the same manner as in Example 1 except that the thickness of the resin thin film 16 was 0.05 mm.

[Example 3]
In this example, the three-dimensional molded circuit component 100 shown in FIG. 1 was manufactured in the same manner as in Example 1 except that the thickness of the resin thin film 16 was 0.1 mm.

[Example 4]
In this example, the three-dimensional molded circuit component 100 shown in FIG. 1 was manufactured in the same manner as in Example 1 except that the thickness of the resin thin film 16 was 0.5 mm.

[Example 5]
In this example, the three-dimensional molded circuit component 100 shown in FIG. 1 was manufactured in the same manner as in Example 1, except that the area of the resin thin film 16 was 4 cm ² (2 cm x 2 cm).

[Example 6]
In this example, the three-dimensional molded circuit component 100 shown in FIG. 1 was manufactured in the same manner as in Example 1, except that the area of the resin thin film 16 was 16 cm ² (4 cm x 4 cm).

[Example 7]
In this example, the three-dimensional molded circuit component 100 shown in FIG. 1 was manufactured in the same manner as in Example 1, except that the area of the resin thin film 16 was 25 cm ² (5 cm x 5 cm).

[Comparative example 1]
In this comparative example, the three-dimensional molded circuit component 100 shown in FIG. 1 was manufactured in the same manner as in Example 1, except that the thickness of the resin thin film 16 was 0.008 mm.

[Comparative example 2]
In this comparative example, the three-dimensional molded circuit component 100 shown in FIG. 1 was manufactured in the same manner as in Example 1, except that the thickness of the resin thin film 16 was 0.7 mm.

[Evaluation of three-dimensional molded circuit parts]
The three-dimensional molded circuit components manufactured in Examples 1 to 7 and Comparative Examples 1 and 2 were evaluated as follows. The results are shown in Table 1.

(1) Moldability of resin thin film The moldability of the resin thin film in integral molding of the base material was evaluated according to the following evaluation criteria.

<Evaluation criteria for moldability of resin thin film>
○: No unfilled portions of molten resin were generated in the resin thin film.
×: Unfilled portions of the molten resin occurred in the resin thin film.

(2) Heat dissipation properties of three-dimensionally molded circuit components A predetermined voltage was applied to the manufactured three-dimensionally molded circuit components to light up an LED. The LED surface temperature was measured using thermography one hour after it was turned on. The heat dissipation properties of the three-dimensional molded circuit components were evaluated according to the following evaluation criteria.

<Evaluation criteria for heat dissipation of three-dimensionally molded circuit components>
○: The LED surface temperature 1 hour after lighting was 100° C. or less.
×: The LED surface temperature exceeded 100° C. one hour after lighting.

As shown in Table 1, in Examples 1 to 7 in which the thickness of the resin thin film was within the range of 0.01 mm to 0.5 mm, both the moldability of the resin thin film and the heat dissipation of the three-dimensionally molded circuit component were good. there were. Comparing Examples 1 to 4, which differ only in the thickness of the resin thin film, it is found that the thinner the resin thin film, the lower the LED surface temperature one hour after lighting, and the higher the heat dissipation of the three-dimensional molded circuit component. I understand. Comparing Examples 1 and 5 to 7, which differ only in the area of the resin thin film, it was found that the larger the area of the resin thin film, the lower the LED surface temperature 1 hour after lighting, and the better the heat dissipation of the three-dimensionally molded circuit component. was found to be high. The larger the area of the resin thin film, the more difficult it is to mold the resin thin film, but even in Example 7 where the resin thin film was 25 cm ² , no unfilled portions of the molten resin occurred and the moldability was good.

On the other hand, in Comparative Example 1, where the resin thin film was as thin as 0.008 mm, unfilled portions of the molten resin occurred, and the moldability was poor. Therefore, in Comparative Example 1, the heat dissipation performance of the three-dimensionally molded circuit component was not evaluated. In Comparative Example 2, in which the resin thin film was as thick as 0.7 mm, the heat dissipation of the three-dimensionally molded circuit component was poor.

[Example 8]
In this example, a three-dimensional molded circuit component was manufactured in the same manner as in Example 1, except that an aluminum heat radiation fin was used instead of an aluminum plate as the metal part. That is, the three-dimensional molded circuit component manufactured in this example is the three-dimensional molded circuit component 200 shown in FIG.

As in Example 1, (1) moldability of the resin thin film and (2) heat dissipation of the three-dimensionally molded circuit component were evaluated. The moldability of the resin thin film was good. The heat dissipation of the three-dimensional molded circuit component was also good, and the LED surface temperature 1 hour after lighting was 70°C, which was 10°C lower than in Example 1. From this result, it was confirmed that heat dissipation performance was improved by using heat dissipation fins in the metal part.

[Example 9]
In this example, the thickness of the resin thin film was 0.15 mm, the resin portion of the base material was foam-molded, and the mounting component (LED) was mounted on the base material by laser soldering (spot mounting). A three-dimensional molded circuit component was manufactured in the same manner as in Example 1 except for the above. That is, the three-dimensionally molded circuit component manufactured in this example is a three-dimensionally molded circuit component 300 shown in FIG. In this example, the base material was integrally molded by insert molding using a mold similar to that used in Example 1, but the molding apparatus disclosed in FIG. 11 of WO2013/027615 was used as the molding apparatus. The resin part was foam-molded using pressurized nitrogen as a physical foaming agent. The nitrogen filling pressure was 10 MPa, and the back pressure valve pressure of the vent pressure reduction section was 6 MPa.

The resin portion 32 of the obtained three-dimensional molded circuit component 300 had a specific gravity approximately 8% lower than that of a solid (non-foamed material). The cross sections of the resin portion 32 and the resin thin film 36 were observed using a microscope. The cell diameter of the cells 39 of the resin portion 32 was as fine as 30 to 80 μm. On the other hand, no foam cells were found in the cross section of the resin thin film 36. That is, the resin thin film 36 did not substantially contain foam cells. Further, in the laser soldering method (spot mounting) of the mounted component (LED), no blistering was observed in the resin thin film 36 irradiated with laser light.

Furthermore, in the obtained three-dimensional molded circuit component 300, an experiment was conducted in which the resin part 32 including the foamed cells 39 was irradiated with the same laser light as used in the laser soldering method (spot mounting). When the laser beam was irradiated, the resin portion 32 including the foamed cells 39 swelled. From this result, it was found that although the heat resistance of the resin part 32 is reduced by performing foam molding, the heat resistance of the resin thin film 36 on which the LED is mounted can be maintained by not forming foam cells in the resin thin film 36. . The three-dimensional molded circuit component 300 of this example succeeded in reducing the weight of the entire component while maintaining the heat resistance of the LED mounting portion.

[Example 10]
In this example, a three-dimensional molded circuit component 400 is manufactured using a base material 40 shown in FIG. 7 in which a metal part 41 and a resin part 42 are integrally molded, and a resin thin film 46 is formed of a thermosetting resin. did. Further, as the mounting component 15, an LED (light emitting diode) was used.

(1) Manufacture of base material An aluminum block is used for the metal part 41, and an aromatic polyamide containing an inorganic filler similar to the resin used in Example 1 (manufactured by Toyobo, Vyroamide GP2X-5, melting point 310) is used for the resin part 42. ℃) was used. Further, for the resin thin film 46, polyimide, which is a thermosetting resin, containing boron nitride powder with an average particle size of 4 μm as an insulating heat dissipating material was used.

First, polyamic acid, which is a polyimide precursor, and boron nitride powder are dispersed and dissolved in N-methyl-2-pyrrolidone (NMP) to create a resin with a polyimide concentration (solid content concentration) of 12% by weight and a boron nitride concentration of 50% by weight. A slurry solution was prepared. The prepared resin slurry solution was applied to the surface 41a of the metal part 41, and heated at 350° C. for 30 minutes to harden it, thereby forming a resin thin film 46. The area of the resin thin film 46 was 1 cm ² (1 cm×1 cm), and the thickness t ₄₆ was 20 μm. Further, the content of boron nitride powder in the resin thin film 46 was 70% by volume.

A mold having a cavity corresponding to the base material 40 shown in FIG. 7 was prepared. The mold cavity was provided with a portion corresponding to the recess 43 (a protrusion inside the cavity). In order to improve the adhesion between the metal part 41 and the resin part 42 using nanomolding technology (NMT), the surface of the metal part 41 (aluminum block) was etched. The etched metal part 41 was placed at an appropriate position in the cavity of the mold, and aromatic polyamide was injected and filled into the empty space in the cavity to perform insert molding. Insert molding was performed using the same injection molding apparatus as in Example 1 under the same molding conditions (mold temperature 140°C, resin temperature 340°C). A recess 43 was formed in the obtained base material 40, which was defined by a side wall 43a formed by the resin part 42 and a bottom 43b formed by the resin thin film 46. The depth of the recess 43 was 1.8 mm.

(2) Formation of circuit pattern and mounting of mounted components A circuit pattern 14 formed of a plating film was formed on the resin portion 42 by the same method as in Example 1. In this example, the circuit pattern 14 was formed on the resin thin film 46 without any disconnection. Next, the mounting component (LED) 15 was mounted in the recess 43 formed on the base material 40 by the same method as in Example 1. As a result, a three-dimensional molded circuit component 400 shown in FIG. 7 was obtained.

The heat dissipation properties of the three-dimensionally molded circuit components were evaluated by the same method as in Example 1. The heat dissipation of the three-dimensional molded circuit component was good, and the LED surface temperature 1 hour after lighting was 65° C., which was 15° C. lower than in Example 1. From this result, it was confirmed that heat dissipation is enhanced by making the resin thin film thinner and further containing a heat dissipating material. Furthermore, it was confirmed that a thin resin film could be easily produced by using a thermosetting resin.

[Example 11]
This example is the same as Example 1 except that a strongly basic electroless copper plating solution (manufactured by Okuno Pharmaceutical Co., Ltd., pH 12) was used instead of a neutral electroless nickel phosphorus plating solution in forming the circuit pattern. A three-dimensional molded circuit component was manufactured using a similar method.

The surface of the metal part (aluminum plate) of the three-dimensionally molded circuit component obtained in this example was corroded, and copper was precipitated in a part. The adhesion of the deposited copper was low and it was easily peeled off. After peeling off and removing the corroded parts and copper on the surface of the metal part, the heat dissipation of the three-dimensionally molded circuit component was evaluated in the same manner as in Example 1. The heat dissipation of the three-dimensionally molded circuit component of this example was good, and the LED surface temperature 1 hour after lighting was 80° C., which was the same as that of Example 1. From this result, it was found that when aluminum is used for the metal part and a strongly basic plating solution is used as the plating solution, corrosion of the metal part occurs. However, it was confirmed that if the corroded parts and copper on the surface of the metal parts were removed, there would be no problem in the practical use of the three-dimensional molded circuit component.

The three-dimensionally molded circuit component of the present invention has high heat dissipation properties, is easy to mold, and has high productivity. Therefore, it is possible to suppress the three-dimensionally molded circuit component from becoming hot due to heat generated by mounted components such as LEDs. The three-dimensional molded circuit component of the present invention can be applied to smartphones and automobile parts.

10, 30, 40 Base material 11, 21, 41 Metal part 12, 32, 42 Resin part 14 Circuit pattern 13, 33, 43 Recess 13a, 43a Side wall of recess 13b, 43b Bottom of recess 15 Mounted parts 16, 36, 46 Resin thin film 39 Foamed cells 100, 200, 300, 400 Three-dimensional molded circuit parts

Claims (9)

A three-dimensional molded circuit component,
a base material including a metal part and a resin part containing a filler;
a resin thin film containing a thermosetting resin or a photocurable resin formed on the metal part;
a circuit pattern formed by an electroless plating film on the resin part and the resin thin film;
a mounted component mounted on the resin thin film and electrically connected to the circuit pattern formed on the resin thin film on the back surface thereof,
The resin thin film and the resin part are formed of different resins,
The resin part has a roughened part on the surface, the filler is exposed in the roughened part, and the circuit pattern is formed in the roughened part. Original molded circuit parts. The three-dimensional molded circuit component according to claim 1, wherein the thin resin film has a thickness of 0.01 mm to 0.5 mm. The three-dimensional molded circuit component according to claim 1 or 2, wherein the resin thin film contains an insulating heat dissipating material. The three-dimensional molded circuit component according to any one of claims 1 to 3, wherein the resin portion includes foam cells. 5. The three-dimensional molded circuit component according to claim 4, wherein the resin portion includes foam cells, and the resin thin film substantially does not include foam cells. The three-dimensional molded circuit component according to any one of claims 1 to 5, wherein the mounted component is an LED. The three-dimensional molded circuit component according to any one of claims 1 to 6, wherein a nickel phosphorus film is formed on the surface of the metal part. The three-dimensional molded circuit component according to any one of claims 1 to 7, wherein the resin portion has a thickness of 0.5 mm or more. The three-dimensionally molded circuit component according to any one of claims 1 to 8, wherein the resin thin film has an area of 0.1 cm ² to 25 cm ² for each mounted component placed on the resin thin film.

Images