JP7058412B2 - Manufacturing method of 3D resin molded circuit parts - Google Patents

Description

The present invention relates to a three-dimensional resin molded circuit component in which a conductor circuit pattern is integrally formed on a resin molded body having a three-dimensional structure, a manufacturing method thereof, and an intermediate component for plating.

As a component to be incorporated into various electric and electronic devices such as computers, mobile phones, smartphones, and electrical components of automobiles, for example, a resin molded body having a three-dimensional structure having a desired shape is molded by injection molding using a mold, and the surface thereof is formed. , A component (three-dimensional resin molded circuit component) called an MID (Molded Interconnect Device) that directly forms a conductor circuit having a desired pattern is known.

In this three-dimensional resin molded circuit component, a desired conductor circuit pattern is formed on the surface of the resin molded body as a component (base material), so that the electrical / electronic device incorporating this is separate from the component. Compared to general electrical and electronic equipment that must incorporate a printed circuit board for driving, it is possible to reduce the size (space saving), thinning, weight reduction, and multifunctionality. ..

Various methods are known as a method of directly forming a conductor circuit pattern on the surface of a resin molded body. For example, in Patent Document 1, a metal thin film is formed on the entire surface of a resin molded product by a method such as electroplating, sputtering, or vacuum vapor deposition, and then the metal thin film is irradiated with laser light to obtain a target conductor circuit pattern. A method is disclosed in which a conductor circuit pattern is formed by removing all the remaining metal thin films, and the conductor circuit pattern is electroplated with copper, for example, to obtain a conductor circuit having a desired thickness.

Further, in Patent Document 2, for example, the surface of the resin molded product is chemically etched to form a roughened surface having an uneven structure, and a plating resist is applied to the surface of the roughened surface other than the portion corresponding to the target conductor circuit pattern. After (masking), a catalyst solution containing a metal that becomes a catalyst nucleus during chemical (non-electrolytic) plating is applied to the uneven structure of the part corresponding to the exposed conductor circuit pattern, and the catalyst nucleus is adhered. A method is disclosed in which a conductor circuit having a desired thickness is obtained by subjecting it to, for example, electrolytic plating of copper.

Japanese Unexamined Patent Publication No. 6-164105 Japanese Unexamined Patent Publication No. 8-288621

However, the above-mentioned prior art has the following problems.
Patent Document 1 requires at least three steps of a resin molding step, a laser processing step performed on each of the obtained resin molded products, and an electroless plating step when manufacturing the target circuit component. Become. In other words, in the case of Patent Document 1, an expensive laser irradiation device and its complicated operation are required, the manufacturing cost is high, the manufacturing time is long, and the circuit parts are manufactured individually, which is suitable for mass production. There is a problem that it is not.

In the case of Patent Document 2, for each of the resin molded products obtained in the resin molding process, at least the etching process for making the entire surface of each surface roughened, and the portion corresponding to the target conductor circuit pattern are not included. Five steps are required: a step of applying a plating resist to the surface of the surface, a step of electroless plating performed on the portion corresponding to the conductor circuit pattern, and a step of removing the last applied plating resist. In this case as well, as in the technique disclosed in Patent Document 1, the manufacturing process is complicated, the manufacturing cost of circuit parts is high, the manufacturing time is long, and it is not suitable for mass production of circuit parts. There is.

Further, all of the manufacturing methods disclosed in Patent Documents 1 and 2 can be applied to a relatively flat outer surface of the surface of the resin molded product, but even the outer surface has deep recesses. It is virtually impossible to form the desired conductor circuit pattern on the surface portion of the resin molded product or on the inner surface of the through hole penetrating the inside of the resin molded product from one outer surface of the resin molded product toward the other outer surface. There is the problem that it is possible. Therefore, on the surface of the resin molded body obtained by resin molding, the place where the conductor circuit pattern is formed is restricted.

The present invention solves the above-mentioned problems of the prior art, eliminates the need for dedicated processes and equipment such as a laser irradiation process for individually forming a conductor circuit pattern on each resin molded product, a masking process, and an etching process, and a conductor circuit. The pattern can be formed on a plurality of resin molded bodies at the same time or continuously, and the manufacturing time and manufacturing cost can be reduced. At the same time, conductors can be formed on each surface of deep recesses and through holes of the resin molded body. An object of the present invention is to provide a three-dimensional resin molded circuit component capable of forming a circuit pattern and further reducing variation in the position accuracy of the conductor circuit pattern, a manufacturing method thereof, and an intermediate component for plating.

In order to solve the above-mentioned problems, the three-dimensional resin molded circuit component of the present invention is a three-dimensional resin molded circuit component in which a conductor circuit pattern is formed on the surface of the resin molded body, and is a surface of the resin molded body. In addition, it has a hydrophilic region having a concavo-convex structure formed by a pattern corresponding to the conductor circuit pattern, the conductor circuit pattern covers the hydrophilic region, and acts as a catalyst nucleus during electroless plating. It is characterized by having a conductive base layer containing the metal particles to be formed and a metal plating layer laminated on the conductive base layer.

It is preferable that at least a part of the surface of the resin molded product excluding the hydrophilic region is a water-repellent region having an uneven structure.
It is preferable that the metal particles are metal nanoparticles, further, the metal particles are silver nanoparticles, and the metal plating layer is a copper plating layer.

Further, the method for manufacturing a three-dimensional resin molded circuit component of the present invention is a method for manufacturing a three-dimensional resin molded circuit component in which a conductor circuit pattern is formed on the surface of a resin molded body, and is a hydrophilic region having a concavo-convex structure. Resin molding is performed using a mold in which the transfer portion is formed on the mold surface with a pattern corresponding to the conductor circuit pattern, and the hydrophilic region having the uneven structure to which the hydrophilic region transfer portion is transferred is surfaced. A metal particle dispersion liquid containing metal particles acting as a catalyst nucleus during electroless plating is brought into contact with the hydrophilic region of the obtained resin molded body in the step of obtaining the resin molded body having the above-mentioned hydrophilic region. A step of forming a conductive base layer containing metal particles, and a step of subjecting the conductive base layer to electroless plating of a conductive metal and laminating a metal plating layer made of the conductive metal on the conductive base layer. It is characterized in that a conductor circuit pattern including the conductive base layer and the metal plating layer is formed on the hydrophilic region.

As the mold, a mold having a water-repellent region transfer portion having a concavo-convex structure formed on at least a part of the mold surface excluding the hydrophilic region transfer portion is used, and the resin molding excluding the hydrophilic region is used. It is preferable to use a water-repellent region having an uneven structure at least a part of the surface of the body.
It is preferable that the treatment for bringing the metal particle dispersion liquid into contact is a treatment for immersing the resin molded body in the metal particle dispersion liquid or a treatment for applying the conductive dispersion liquid to the hydrophilic region, and the dipping treatment. After that or after the coating treatment, it is preferable to further perform a drying treatment or a baking treatment. Further, it is preferable to use metal nanoparticles as the metal particles.

Further, the intermediate part for plating of the present invention is an intermediate part for plating made of a resin molded body for manufacturing a three-dimensional resin molded circuit part having a conductor circuit pattern formed on the surface by a plating process, and is the resin molding. On the surface of the body, a hydrophilic region formed of an uneven structure formed by a pattern corresponding to the conductor circuit pattern, and a water-repellent region formed of an uneven structure formed on at least a part of the surface excluding the hydrophilic region. It is characterized by having.

In the three-dimensional resin molded circuit component of the present invention, a hydrophilic region of a pattern corresponding to a target conductor circuit pattern is formed on a resin molded body as a base material. Therefore, a conductive base layer made of metal particles can be formed in the hydrophilic region only by bringing this resin molded body into contact with a metal particle dispersion liquid containing metal particles acting as a catalyst nucleus. Therefore, the conductor circuit pattern composed of the conductive base layer and the metal plating layer formed on the conductive base layer can be formed without performing special treatment such as laser processing, masking processing, and etching processing as in the conventional case.

Further, since the hydrophilic region formed on the surface of the resin molded body is a region to which hydrophilicity is imparted by forming the surface into an uneven structure, the hydrophilic region corresponds to the portion of the mold surface of the mold. By forming the hydrophilic region transfer portion of the concavo-convex structure that exhibits the property, it is possible to form the target resin molded product and at the same time form the hydrophilic region on the surface of the resin molded product.
Therefore, the resin material used for the resin molded body may be any material as long as it can be molded, and the material cost and the overall manufacturing cost are reduced.

Further, since it is only necessary to form a hydrophilic region transfer portion having a concavo-convex structure that exhibits hydrophilicity on the mold side, it is not necessary to individually process the conductor circuit pattern for each resin molded body. However, the manufacturing process is simplified, which contributes to a significant reduction in manufacturing cost and manufacturing time.
Further, since the hydrophilic region can be formed only by resin molding, the desired conductor circuit pattern can be formed on the concave surface of the resin molded body and the inner surface (inner surface) of the through hole.

Further, when a water-repellent region having a concavo-convex structure is formed on the surface of the resin molded body in addition to the hydrophilic region, the metal particle dispersion used for forming the conductive base layer stays in the region other than the hydrophilic region. This can be suppressed more reliably, and the position accuracy of the obtained conductor circuit pattern becomes high.

FIG. 1 is a perspective view showing a three-dimensional resin molded circuit component according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. FIG. 3 is an enlarged cross-sectional view taken along the line III-III of FIG. FIG. 4 is a perspective view showing an example of an uneven structure forming a hydrophilic region. 5A and 5B are views schematically showing an example of a mold, FIG. 5A is a schematic cross-sectional view seen from one side, and FIG. 5B is a schematic cross-sectional view seen from a direction orthogonal to (a). .. FIG. 6 is a cross-sectional view of the resin molded body molded by the mold of FIG. 7A and 7B are views showing a three-dimensional resin molded circuit component according to another embodiment of the present invention, FIG. 7A is a perspective view seen from the upper surface, and FIG. 7B is a perspective view seen from the back surface. (C) is the A arrow view of (b). FIG. 8 is a cross-sectional view taken along the line VIII-VIII of FIG. FIG. 9 is a perspective view showing an example of an uneven structure forming a water-repellent region.

An embodiment of the present invention will be described below with reference to the drawings.
1 is a perspective view showing a three-dimensional resin molding circuit component A according to the present embodiment, FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1, and FIG. 3 is a cross-sectional view taken along line III-III of FIG. It is a partial notch enlarged view of the cross section along.

In FIGS. 1 and 2, the three-dimensional resin molding circuit component A is formed with a through hole 2 penetrating from the upper surface 1a of the resin molded body 1 as a base material toward the lower surface 1b. The conductor circuit pattern 3 is formed on the upper surface 1a, the lower surface 1b, the side surfaces 1c, and 1d of the resin molded body 1 in a desired pattern, and the conductor circuit pattern 3 is also formed on the inner surface 2a of the through hole 2. ..

FIG. 3 is a cross-sectional view showing an integral coupling structure between the surface of the resin molded body 1 and the conductor circuit pattern 3 formed therein, and is a cross-sectional view showing the surface of the resin molded body 1 on which the conductor circuit pattern 3 is formed. In the figure, a hydrophilic region 4 is formed on a partial surface of the upper surface 1a). The hydrophilic region 4 is composed of a concave-convex structure 4A in which a convex portion 4a and a concave portion 4b are combined. The configuration of the concave-convex structure 4A having a hydrophilic function is not limited in any way, and the shape of the convex portion 4a and the concave portion 4b (ridge-shaped, polygonal, circular, etc.) and the rising angle of the convex portion 4a from the concave portion 4b. By appropriately setting the height of the convex portion 4a (the same as the depth of the concave portion 4b), the width of the convex portion 4a, and the pitch interval between the convex portion 4a and the concave portion 4b (the groove width of the concave portion 4b), the contact angle of the water droplet is set. It can be formed as a surface exhibiting hydrophilicity having a temperature of less than 90 degrees.

As shown in FIG. 4, the concave-convex structure 4A forming the hydrophilic region 4 of the present embodiment has a plurality of convex portions 4a extending in a ridge shape having a rectangular cross section along the wiring direction (X direction) of the conductor circuit pattern 3. Are arranged in the line width direction (Y direction) of the conductor circuit pattern 3, and the concave portions 4b have a structure extending in a groove shape along the convex portion 4a. For example, in the example of FIG. 4, the width of the concave portion 4b in the cross-sectional direction is 20 to 35 μm, the pitch of the convex portion 4a in the cross-sectional direction (distance between the width centers of the adjacent convex portions 4a) is 40 to 60 μm, and the convex portion 4a. By setting the height (depth of the recess 4b) to 30 to 50 μm, only the surface on which the uneven structure 4A is formed can be designated as the hydrophilic region 4 on the surface of the resin molded body 1.

Further, the hydrophilicity can be further enhanced by forming each surface of the convex portion 4a and the concave portion 4b into a fine uneven structure having each dimension of about 1/5 to 1/10 of the above along the width direction. .. In addition, for example, as shown in Utility Model Registration No. 3188769, the hydrophilic region 4 can be formed by the convex portions 4a and the concave portions 4b having various shapes and dimensions.

The hydrophilic region 4 composed of such an uneven structure 4A is formed on the surface of the resin molded body 1 at the same time as molding the resin molded body 1 at the time of resin molding using a mold in the resin molding step described later. The surface of the hydrophilic region 4 made of the uneven structure 4A is covered with the conductive base layer 5.

The conductive base layer 5 is formed by adhering metal particles, preferably nm-order metal particles (metal nanoparticles), which act as catalyst nuclei when electroless plating the conductive metal in the metal plating laminating step described later. It is a thin conductive coating layer.

Examples of the metal constituting the metal particles (preferably metal nanoparticles) used in the conductive base layer 5 include silver, gold, copper, palladium, nickel and the like, and one or more of them can be mentioned. It may be included. However, gold, silver, and copper are preferable from the viewpoint of conductivity, silver (preferably silver nanoparticles) is more preferable because it is less likely to oxidize than copper and is cheaper than gold.

The metal plating layer 6 is laminated on the conductive base layer 5, and the conductor circuit pattern 3 is formed. Specifically, the conductive base layer 5 is subjected to electroless plating treatment of the conductive metal to be plated and deposited, and the concave-convex structure 4A is formed in a state of being entirely embedded. Examples of the conductive metal include copper, nickel, silver, and gold, but copper is preferable from the viewpoint of conductivity and economy. In addition, when forming the metal plating layer 6, it is also possible to perform ordinary electrolytic plating further after the electroless plating treatment described above.

Next, a manufacturing method of the three-dimensional resin molding circuit component A will be described with reference to the drawings.
(Resin molding process)
In this step, at the same time as molding the resin molded body 1, the uneven structure 4A (hydrophilic region 4) of the pattern corresponding to the target conductor circuit pattern 3 is formed on the surface thereof. The pattern of the uneven structure 4A is integrally formed on the surface of the resin molded body 1 molded by resin molding (for example, injection molding) using a mold.

First, the mold 7 shown in FIGS. 5 (a) and 5 (b) is prepared. The mold 7 forms a resin molded body 1 having a predetermined shape by combining the upper mold 7A and the lower mold 7B. In this example, the protruding portion for forming the through hole 2 of the resin molded body 1. The 7a is formed so as to protrude from the upper mold 7A in the direction of the lower mold 7B.

Of the mold surfaces of the upper mold 7A and the lower mold 7B (the inner surfaces facing each other), the portion corresponding to the uneven structure 4A which is the hydrophilic region 4 formed on the surface of the resin molded body 1 is the uneven structure 4A. In the same pattern as above, the hydrophilic region transfer portion 71 having a concavo-convex structure having a cross-sectional shape obtained by reversing the concavo-convex structure 4A is formed. Therefore, the hydrophilic region transfer portion 71 is transferred to the surface of the resin molded body 1 at the time of molding, and the uneven structure 4A is formed. In order to make the concave-convex structure 4A of the resin molded body function as the hydrophilic region 4, the hydrophilic region transfer portion 71 has the convex portion 71a under exactly the same conditions as the convex portion 4a and the concave portion 4b of the concave-convex structure 4 shown in FIG. And a recess 71b. When forming a concavo-convex structure having a fine convex portion 71a and a concave portion 71b similar to that shown in FIG. 4 as the hydrophilic region transfer portion 71 on the mold surface (inner surface) of the mold 7, a laser is used. It can be formed by an ultrafine processing method using processing, cutting, grinding, semiconductor process processing, or the like.

Next, the resin material is injected using the mold 7. As a result, the resin molded body 1 having the through hole 2 is formed at the position corresponding to the protruding portion 7a. At this time, at the same time as the molding of the resin molded body 1, the hydrophilic region transfer portion 71 formed on the mold surfaces of the upper mold 7A and the lower mold 7B is transferred, so that the convex portion 71a of the hydrophilic region transfer portion 71 is transferred. A concave portion 4b is formed on the surface of the resin molded body 1 at a position corresponding to the above, and a convex portion 4a is formed on the surface of the resin molded body 1 at a position corresponding to the concave portion 71b of the hydrophilic region transfer portion 71. Since the shapes, dimensions, etc. of the convex portion 71a and the concave portion 71b of the hydrophilic region transfer portion 71 are as shown in FIG. 4, fine unevenness having the concave portion 4b and the convex portion 4a having the same shape, dimensions, etc. The structure 4 is formed on the surface of the resin molded body 1. In this way, the resin molded body 1 in which the hydrophilic region 4 composed of the uneven structure 4A of the pattern corresponding to the target conductor circuit pattern 3 is formed on the surface is manufactured (see FIG. 6).

In the present embodiment, the conductive base layer 5 and the metal plating layer 6 are formed in the hydrophilic region 4 formed at the same time as the resin molding in the resin molding step as described later, and laser processing is performed on each of the resin molded bodies 1. Since it is not necessary to perform such as, the resin used here does not need to be a special resin corresponding to laser processing or the like, and is not particularly limited as long as it is a resin capable of mold molding. For example, general-purpose resins such as PPS, PBT, PA, POM, PP, and ABS can be used.

(Conductive base layer forming process)
In this step, the conductive base layer 5 is formed on the surface of the hydrophilic region 4 of the resin molded body 1 manufactured in the resin molding step.
Therefore, the conductive metal is deposited on the hydrophilic region 4 made of the uneven structure 4A transferred to the surface of the resin molded body 1 shown in FIG. 6 when the electroless plating treatment of the conductive metal is performed in the next step. A metal particle dispersion containing nm-order metal particles acting as a catalyst nucleus for causing the plating is brought into contact with the metal particles.

As the treatment for bringing the two into contact with each other, a treatment of immersing the resin molded body 1 in the metal particle dispersion liquid or a treatment of applying the metal particle dispersion liquid using, for example, an inkjet printer or a pipette is preferable. In particular, the dipping process is suitable in that it does not require the use of special equipment.

Since the uneven structure 4A is a hydrophilic region 4, by performing the above treatment, the metal particle dispersion wets the uneven structure 4A (hydrophilic region 4) having a high affinity, and the uneven structure 4A (hydrophilic). While covering the surface of the sex region 4), it has a low affinity and is difficult to adhere to a portion of the surface of the resin molded body 1 other than the hydrophilic region 4. Since the hydrophilic region 4 composed of the concavo-convex structure 4A is formed in the pattern corresponding to the conductor circuit pattern 3 as described above, the metal particle dispersion liquid becomes the conductor circuit pattern 3 in this way, for example, simply by dipping. It will adhere to the surface of the resin molded body 1 in the following pattern.

Next, the resin molded product 1 is dried using warm air, an oven, or the like, and further preferably fired at a temperature of 100 to 300 ° C. for 10 to 120 minutes to prepare a dispersion medium for the metal particle dispersion. It is preferable to remove by evaporation. By performing such a treatment, metal particles (metal nanoparticles) remain on the surface of the concave-convex structure 4A (hydrophilic region 4) as a thin film with a thickness of about 100 nm to 20 μm, and serve as a catalyst nucleus. It becomes a conductive base layer 5 that works effectively.

As the metal particle dispersion liquid, metal particles having a particle size of 1 to 500 nm, preferably 10 to 100 nm are contained in a dispersion medium such as water at a mass ratio of 5% to 60%, more preferably 10% to 30%. Distributed ones are used.

Further, examples of the metal particles include silver nanoparticles, gold nanoparticles and the like as described above. Of these, silver nanoparticles are preferable because they function as catalyst nuclei and are relatively easy to obtain. Examples of the metal particle dispersion liquid containing silver nanoparticles include silver nanoparticles ink.

(Metal plating laminating process)
In this step, electroless plating of the conductive metal is performed on the above-mentioned conductive base layer 5 covering the hydrophilic region 4 composed of the uneven structure 4A, and a conductive metal plating layer is formed on the conductive base layer 5. do. That is, the resin molded body 1 having the conductive base layer 5 is immersed in the electroless plating solution of the conductive metal as it is. Since the metal particles constituting the conductive base layer 5 act as catalyst nuclei, the conductive metal is deposited on the metal particles. Then, if necessary, electrolytic plating is performed to form the metal plating layer 6 (see FIG. 3). At this time, the conductive base layer 5 is formed on the uneven structure 4A (hydrophilic region 4) previously formed so as to correspond to the conductor circuit pattern 3, and the metal laminated on the conductive base layer 5. The plating layer 6 will also be formed in that pattern. Here, a three-dimensional resin molded circuit component A in which a predetermined conductor circuit pattern 3 formed by laminating a conductive base layer 5 and a metal plating layer 6 on the surface of the resin molded body 1 is obtained (see FIG. 1). ).

Examples of the conductive metal used in the metal plating laminating step include copper, nickel, silver, and gold, and it is preferable to use copper because of its excellent conductivity and the like as described above. ..

When the formed conductor circuit pattern 3 is subjected to thermocompression bonding at a temperature of 100 to 300 ° C. and a pressure of about 50 Pa or more after the metal plating laminating step, the concave-convex structure 4A, the conductive base layer 5, and the metal are applied. It is suitable because the mutual adhesion between the plating layers 6 is increased.

Next, another embodiment of the present invention will be described with reference to FIGS. 7 to 9. In the three-dimensional resin molding circuit component A of the above embodiment, only the hydrophilic region 4 formed by the pattern corresponding to the conductor circuit pattern 3 is formed on the surface of the resin molding body 1, but the present embodiment has only been formed. The three-dimensional resin molding circuit component B has a structure in which a water-repellent region 40 composed of an uneven structure 40A is formed on at least a part of the surface excluding the hydrophilic region 4 (see FIGS. 8 and 9). The water-repellent region 40 is particularly preferably formed in the vicinity of the boundary portion 10 with the hydrophilic region 4. As described above, the hydrophilic region 4 is formed at the time of molding the resin molded body 1, and then the conductive base layer 5 is attached to the hydrophilic region 4 only by immersing or applying it in a metal particle dispersion liquid, but at least. By setting the vicinity of the adjacent portion (boundary portion 10) of the hydrophilic region 4 as the water-repellent region 40, the metal particle dispersion does not adhere to the water-repellent region 40 and is selectively formed only in the hydrophilic region 4. The variation in the line width of the metal plating layer 6 formed thereafter becomes small, and the positional accuracy of the conductor circuit pattern 3 becomes high.

Therefore, the resin molded body 1 which is an intermediate component for plating molded in the stage before the conductive base layer forming step and the metal plating laminating step has a pattern corresponding to the conductor circuit pattern 3 as in the present embodiment. The concavo-convex structure 40A formed in the vicinity of the hydrophilic region 4 composed of the formed concavo-convex structure 4A and at least a part of the surface excluding the hydrophilic region 4, preferably at least in the vicinity of the adjacent portion (boundary portion 10) of the hydrophilic region 4. It is desirable that the configuration includes a water-repellent region 40 made of.

Similar to the hydrophilic region 4, the water-repellent region 40 is at least a part of the mold surface (inner surface) of the mold 7 other than the hydrophilic region transfer portion 71, preferably at least an adjacent portion (for example, at least an adjacent portion of the hydrophilic region transfer portion 71). By forming a water-repellent region transfer portion (not shown) at the portion indicated by reference numeral 75 in FIG. 5, the resin molded body 1 is molded, and at the same time, the surface thereof corresponds to the target conductor circuit pattern 3. Along with the hydrophilic region 4 of the pattern, a water-repellent region 40 having an uneven structure 40A can be formed.

For example, the water-repellent region 40 of the present embodiment is formed from the uneven structure 40A as shown in FIG. By appropriately setting the shape, dimensions, etc. of the uneven structure 40A, it is possible to exhibit water repellency in which the contact angle with water droplets is 90 degrees or more. For example, in FIG. 9, the concave-convex structure 40A has a structure in which the convex portions 40a and the concave portions 40b are arranged in a grid pattern in the X direction and the Y direction, the width of the concave portions 40b in the cross-sectional direction is 10 μm or less, and the cross section of the convex portions 40a. Water repellency is imparted by setting the pitch in the direction (distance between the width centers of the adjacent convex portions 40a) to 20 μm or less and the height of the convex portions 40a (depth of the concave portions 40b) to 20 to 50 μm. Further, the cross-sectional shape of the recess 40b is preferably a substantially rectangular shape or a substantially V-shape. The improvement of water repellency can be achieved by forming a finer uneven structure having a size of about 1/5 to 1/10 of these on the surface of the convex portion 40a. In addition, for example, as shown in Utility Model Registration No. 3188770, the water-repellent region 40 can be formed by the convex portions 40a and the concave portions 40b having various shapes and dimensions.

The water-repellent transfer portion formed on the mold 7 in order to form such a water-repellent region 40 may be formed from a fine uneven structure obtained by reversing the concave-convex structure 40A shown in FIG. The same is true for the relationship between the uneven structure 4A of the hydrophilic region 4 and the uneven structure of the hydrophilic region transfer portion 71 described in the above embodiment.

Further, the three-dimensional resin molded circuit component B of the present embodiment is formed with a concave cross section as shown in FIGS. 7A and 7B, and the conductor circuit pattern 3 is formed on the upper surface 1a of the resin molded body 1. It is formed from the to the back side surface 1e through the through hole 2. Further, as shown in FIG. 7C, a recessed portion 1f is formed at the corner portion of the back surface 1e, and a conductor circuit pattern 3 is also formed on the inner surface thereof. Also in this embodiment, since the hydrophilic region 4 is integrally formed at the time of resin molding, it is easy to form a conductor circuit in a portion such as a through hole 2 or such a recessed portion 1f, which has been difficult to form in the past. The conductor circuit pattern 3 can be formed. In FIG. 7, the conductor circuit pattern 3 formed on the upper surface 1a is used as the antenna circuit 3a, and the electronic circuit components 3b such as LEDs, diodes, and resistors are mounted on the conductor circuit pattern 3 along the back surface 1e. Is shown.

According to each of the above embodiments, at the time of resin molding, a hydrophilic region 4 composed of an uneven structure 4A is integrally formed on the surface of the resin molded body 1 as a plating intermediate with a pattern corresponding to the conductor circuit pattern 3. ing. Therefore, the conductive base layer 5 required for laminating the metal plating layer 6 can be formed in the same pattern as the conductor circuit pattern 3 only by contacting the resin molded body 1 with the predetermined metal particle dispersion liquid. Therefore, it is not necessary to process the surface of the resin molded body one by one with a laser or the like in the processing process for obtaining a conductor circuit having a predetermined pattern as in the conventional case, and multiple simultaneous processing or continuous processing is not required. It is suitable for mass production and can contribute to simplification of manufacturing process and reduction of manufacturing cost. Moreover, it is possible to form circuits in various parts such as deep recesses and through holes, and it is possible to provide three-dimensional resin molded circuit parts having a wide range of applications.

A, B 3D resin molding circuit parts 1 Resin molded body 1a Upper surface of resin molded body 1b Lower surface of resin molded body 1c, 1d Side surface 1f of resin molded body 1f Recessed part 2 Through hole 2a Through hole 2 Inner surface 3 Conductor circuit pattern 4 Hydrophilic region 4A Concavo-convex structure (hydrophilic region)
4a Convex part 4b Concave part 40 Water repellent area 40A Concavo-convex structure (water repellent area)
40a Convex part 40b Concave part 5 Conductive base layer (coating layer of metal particles)
6 Metal plating layer 7 Mold 7A Upper mold 7a Protruding part 7B Lower mold 7 of mold 7 Hydrophilic region Transfer part 71a Convex part 71b Concave part

Claims (5)

A method for manufacturing a three-dimensional resin molded circuit component in which a conductor circuit pattern is formed on the surface of a resin molded body.
It is a step of forming a hydrophilic region exhibiting hydrophilicity on the surface of the resin molded product by a concavo-convex structure formed by combining convex portions and concave portions, and has a cross-sectional shape obtained by reversing the concavo-convex structure that is the hydrophilic region. The hydrophilic region transfer portion having an uneven structure is resin-molded using a mold formed on the mold surface with a pattern corresponding to the conductor circuit pattern, and the hydrophilic region transfer portion is transferred to the hydrophilic region. The step of obtaining the resin molded product having a region on the surface and
A metal particle dispersion liquid containing metal particles acting as a catalyst nucleus during electroless plating is brought into contact with the hydrophilic region of the obtained resin molded body, and a conductive underlayer containing the metal particles is formed in the hydrophilic region. The process of forming and
A step of subjecting the conductive base layer to electroless plating of a conductive metal and laminating a metal plating layer made of the conductive metal on the conductive base layer.
Including
A method for manufacturing a three-dimensional resin molded circuit component, characterized in that a conductor circuit pattern including the conductive base layer and the metal plating layer is formed on the hydrophilic region. In order to form a water-repellent region exhibiting water repellency on the surface of the resin molded product by a concave-convex structure formed by combining convex portions and concave portions, at least one of the mold surfaces excluding the hydrophilic region transfer portion is used as the mold. A water-repellent region transfer portion having a cross-sectional shape concavo-convex structure obtained by reversing the concavo-convex structure, which is the water-repellent region, is formed in the portion, and the surface of the resin molded body excluding the hydrophilic region is used. The method for manufacturing a three-dimensional resin molded circuit component according to claim 1, wherein at least a part of the above is a water-repellent region. The treatment according to claim 1 or 2, wherein the treatment of bringing the metal particle dispersion into contact is a treatment of immersing the resin molded product in the metal particle dispersion or a treatment of applying the conductive dispersion to the hydrophilic region. A method for manufacturing 3D resin molded circuit parts. The method for manufacturing a three-dimensional resin molded circuit component according to claim 3, wherein a drying treatment or a firing treatment is further performed after the dipping treatment or the coating treatment. The method for manufacturing a three-dimensional resin molded circuit component according to any one of claims 1 to 4, wherein the metal particles are metal nanoparticles.

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