TWI532246B - Method for forming a circuit on a housing by spraying or laser engraving - Google Patents

Description

Method for manufacturing a circuit case with spraying and laser engraving

The field of the invention relates to a process for metallizing a substrate, in particular to a process for an antenna or circuit of a mobile communication device, and further to a method for manufacturing a housing with an antenna or circuit by spraying and laser engraving. .

Thanks to the rapid development of information technology and the advancement of wireless communication technology, mobile devices have become a necessary communication tool for modern people. As a result, there is an increasing demand for mobile phone functionality. Since the radio waves of the wireless communication must be up-converted, the carrier can be effectively multiplexed, so the antenna must be used for these actions. Antennas are therefore a very important component in wireless communication devices.

The antenna is usually composed of a radio frequency component and its base fixing bracket. The RF component is a shaped metal piece or a flexible printed circuit board or a rigid printed circuit board. Recently, a manufacturing technology of a molded Molded Interconnect Device (MID) antenna has been developed to configure an antenna on a casing of a mobile device. The MID antenna is mainly formed by forming a metal layer of an antenna by chemical plating on the surface of an injection molded plastic part.

Antennas have traditionally been fabricated using molded interconnect circuit components (MIDs) in two different ways: the 2-shot Molding method and the Laser Direct Structuring (LDS) method.

The laser activation (LDS) method refers to first forming a substrate by a plastic injection operation, and the material of the substrate is a plastic material doped with a metal additive, wherein the metal additive can be activated by laser. Laser activation is performed at a predetermined surface on the surface of the substrate. A metal layer is further plated on the surface of the laser activated region as an antenna.

The two-shot casting mold, as its name suggests, does two injection operations. The steps are as follows: first, a plastic injection operation is used to form a substrate (generally, an electronic device casing), and a blank is reserved in the injection operation. The recessed area corresponds to the line of the antenna. A second injection operation is performed to inject the plateable plastic into the recessed area. Then, a metal layer is formed on the surface of the second shot plastic by electroless plating, and the metal layer is an antenna.

Whether it is the use of two-shot molding or laser activation (LDS) to make the antenna, it is usually necessary to paint on the surface of the substrate to protect the antenna and to decorate the appearance or change the touch, only in the traditional method of this type. The antenna metal layer is already higher than the surface of the surrounding substrate, so after painting, the paint layer will protrude upward at the antenna, which affects the aesthetic appearance.

In addition, if the antenna is manufactured on the plastic surface by the double-shot molding method, the injection molding mold must be modified every time the antenna shape is adjusted, which is time consuming and laborious.

The inventor of the present invention has encountered the problems encountered in forming the antenna on the casing, so that there is a new method for solving the above problems in the prior art.

The object of the present invention is to provide a method for manufacturing a casing with an antenna or a circuit by spraying and laser engraving, so that the surface of the casing naturally produces a flat appearance after forming a circuit metal layer and painting, and exhibits a beautiful texture. In addition, this method adopts the spraying method combined with the laser engraving method, and is applied to the double-shot casting method to manufacture the circuit. When the shape of the circuit changes, only the path of the laser engraving needs to be adjusted, and it is not necessary to separately manufacture or modify the injection mold, thereby effectively shortening the adjustment. The time required for the circuit map. In this case, the circuit especially refers to the antenna circuit (referred to as an antenna in the text)

In order to achieve the above object, the present invention provides a method for manufacturing a casing with an antenna or a circuit by spraying and laser engraving, mainly for taking a substrate as an electroless plating antenna or circuit; wherein the substrate is plastic or necessary Electroless plating can be performed after laser activation; the substrate is coated with a spray coating having a thickness approximately equal to the thickness of the antenna (or circuit) metal layer; applying laser engraving will correspond to the antenna ( Or the circuit layer of the pattern is removed such that the underlying molding substrate is exposed to form a ray engraving area; if it is a second plastic, laser light activation must be performed on the ray engraving area; a method of plating to form a metal layer on the laser-engraved area; a thickness of the antenna (or circuit) metal layer formed by electroless plating is approximately equal to a thickness of the coating layer; and a metal layer of the antenna (or circuit) and the periphery thereof The surface of the coated coating is overlaid with another spray coating; thus, the coated coating can effectively shield the antenna (or circuit) metal layer on the substrate to produce a flat appearance. The method can also be used in the method of two-shot molding, in which case the plastic can be plated as the second shot material, and then the plastic can be plated to perform the above-described procedure.

In view of the structural composition of the case, and the functions and advantages that can be produced, in conjunction with the drawings, a preferred embodiment of the present invention is described in detail below. It should be understood that the following instructions are only applicable to one of the cases and are not intended to limit the scope of the case. The scope of the powers of this case is defined by the scope of the patent application below.

The process of the present invention is primarily a method of forming an antenna or circuit and a flat appearance on a substrate. The surface of the substrate is first coated with a spray coating having a thickness approximately equivalent to the thickness of the antenna (or circuit) metal layer that will be formed later. The laser engraving is then applied to remove the sprayed layer corresponding to the antenna (or circuit) pattern such that the underlying injection molded substrate is exposed and then electrolessly plated to form an antenna (or circuit) metal layer. Finally, another sprayed layer is overlaid on the surface of the above-mentioned antenna (or circuit) metal layer and the surrounding coated layer to produce a flat appearance. The process of the present invention is mainly applied in three different processes. The following description mainly refers to the process of the antenna as a description, but the present case can also be applied to the process of the general circuit, so the following description can also be used peer-to-peer. The process of forming a circuit on a substrate, the invention is described as follows: The first embodiment of the process of the present invention is described as follows: First, a substrate 10 (a substrate of a molded interconnect circuit component (MID)) is taken as an antenna. Substrate. The substrate 10 is a plastic that can be electrolessly plated after laser activation, such as a plastic material of the LDS (Laser Direct Structuring) grade.

The substrate 10 is coated with a spray coating 20 (as applied by painting) having a thickness approximately equal to the thickness of the antenna metal layer to be formed thereafter (please refer to FIG. 1A and FIG. 1B).

Applying laser engraving, the portion of the sprayed layer 20 corresponding to the antenna pattern is removed such that the underlying molding substrate is exposed to form a relief region 30, as shown in FIG.

The surface of the substrate of the laser engraving area 30 is activated by laser light; a metal layer 40 is formed on the laser engraving area 30 by electroless plating (as shown in FIG. 3).

The thickness of the antenna metal layer formed by electroless plating is approximately equal to the thickness of the above-mentioned coated sprayed layer, that is, the thickness of the antenna metal layer 40 is equivalent to the thickness of the sprayed layer 20 around it.

Another spray coating layer 50 is disposed on the surface of the antenna metal layer 40 and the surrounding spray coating layer 20 (as shown in FIG. 4). As such, the recoated coating layer 50 effectively shields the antenna metal layer 40 on the substrate, resulting in a flat appearance.

Referring to FIG. 5A and FIG. 5B, an application example of the present invention is shown in which a contact is formed on the other side (back side) of the substrate for grounding or signal feeding and feeding of the antenna. In the method according to the present invention, a through hole 60 is formed in the substrate 10. Preferably, the through hole has a funnel shape (or a tapered shape), and the cross section is minimum on the front side, and then gradually becomes larger. To the maximum of the back side of the substrate 10, this architecture facilitates the subsequent laser engraving and appearance. In the present case, the contact is provided on a protrusion 61 on the back side (as shown in Figures 5A and 5B).

In the step shown above, a spraying operation is performed on the front side of the substrate 10 to form a spray coating layer 20 (please refer to Fig. 6). If the substrate 10 is injection molded using a plastic material of the LDS (Laser Direct Structuring) grade, the laser engraving is applied first, and the portion of the sprayed layer 20 corresponding to the antenna pattern is removed, so that the underlying molding substrate is exposed. A lightning engraving area 30 is formed, as shown in FIG. Then, laser activation is performed to form a laser activation region 62 according to the antenna, the contacts, and the communication path between the antenna and the contacts (Fig. 8). Finally, a metal layer (shown in FIG. 9) is formed on the laser activation region 62 by electroless plating, and the metal layer includes the antenna 40, the junction 42, and the communication path 41 of the two.

Finally, another sprayed layer 50 (shown in FIG. 10) is overlaid on the surface of the above-mentioned antenna metal layer 40 and the surrounding sprayed coating layer 20. As such, the recoated coating layer 50 effectively shields the antenna metal layer 40 on the substrate, resulting in a flat appearance.

The second embodiment of the present invention is described below, and the same components are denoted by the same reference numerals in the following description for convenience of understanding and explanation. In this embodiment, a general plateable plastic (such as Acrylonitrile-Butadiene-Styrene copolymers (ABS)) or a mixture of ABS and polycarbonate (PC) is used. Substrate. Generally, the electroplatable plastic can be directly electrolessly plated thereon without the step of laser light activation. The steps are as follows: first, a substrate 10 which can be plated as an antenna is taken. A surface of the substrate 10 is coated with a spray coating 20 (as applied by painting), the thickness of the sprayed layer being approximately equal to the thickness of the antenna metal layer to be formed later (please refer to FIG. 11A and FIG. The right side of Figure XI is the cross-sectional view).

Using laser engraving, the portion of the spray coating 20 corresponding to the antenna pattern is removed such that the underlying molding substrate is exposed to form a relief region 30, as shown in FIG. An antenna metal layer 40 is formed on the laser-engraved region 30 by electroless plating (as shown in FIG. 13). The thickness of the antenna metal layer formed by electroless plating is approximately equal to the thickness of the above-mentioned coated sprayed layer, that is, the thickness of the antenna metal layer 40 is equivalent to the thickness of the sprayed layer 20 around it.

Another spray coating layer 50 is disposed on the surface of the above-mentioned antenna metal layer 40 and the surrounding sprayed layer 20 (as shown in FIG. 14). As such, the recoated coating layer 50 effectively shields the antenna metal layer 40 on the substrate, resulting in a flat appearance.

In the present case, at the time of electroless plating, the surface of the sprayed layer 20 may be roughened by the roughening step of the electroless plating, so that the step of roughening may be performed before the first sprayed layer 20 is sprayed.

A practical application example of the second embodiment is as follows, in which a contact is formed on the other side (back side) of the substrate for grounding or signal feeding and feeding of the antenna. In the method according to the present invention, a through hole 60 is formed in the substrate 10. Preferably, the through hole has a funnel shape (or a tapered shape), and the cross section is minimum on the front side, and then gradually becomes larger. The back surface of the substrate 10 is the largest. In the present case, the contact is provided on a protrusion 61 on the back side (as shown in FIGS. 15A and 15B).

In the above-described steps, a spraying operation is performed on the surface of the substrate 10 to form a sprayed layer 20 (refer to Fig. 16). The portion of the sprayed layer 20 corresponding to the antenna pattern is removed such that the molding substrate beneath the sprayed layer is exposed, as shown in FIG. Then, according to the antenna to be fabricated, the contact and the communication path between the antenna and the contact are electrolessly plated to form a metal layer (as shown in FIG. 18), and the metal layer includes the antenna 40, the contact 42, and both. The communication path 41.

Finally, another sprayed layer 50 (shown in FIG. 19) is overlaid on the surface of the above-mentioned antenna metal layer 40 and the surrounding sprayed layer 20. As such, the recoated coating layer 50 effectively shields the antenna metal layer 40 on the substrate, resulting in a flat appearance.

The third embodiment of the present invention is described below, and the same components are denoted by the same reference numerals in the following description for convenience of understanding and explanation. In the present embodiment, the method of the present invention is applied to a 2-shot molding technique. The step is: when the first molding is performed, a non-platable plastic (such as polycarbonate) is used as the substrate 10, wherein the depressed portion 11 is formed on the substrate 10 in the region where the antenna is to be formed, as shown in FIG. 20A and II. The one shown in 10B). A second molding is then performed on the substrate 10, i.e., a plateable plastic is cast into the recessed region 11 to form a plateable plastic region 12. The substrate 10 (including the platable plastic region 12) is coated with a spray coating 20 (such as a method of applying paint), and the thickness of the sprayed layer is approximately equal to the thickness of the antenna metal layer to be formed later (refer to FIG. eleven).

Applying laser engraving, the portion of the sprayed layer 20 corresponding to the antenna pattern is removed within the range of the platable plastic zone 12 such that the underlying plateable plastic molding substrate is exposed to form a slashed area 30, such as Figure 22 shows the person. An antenna metal layer 40 is formed on the laser-engraved region 30 by electroless plating (as shown in FIG. The thickness of the antenna metal layer formed by electroless plating is approximately equal to the thickness of the above-mentioned coated sprayed layer, that is, the thickness of the antenna metal layer 40 is equivalent to the thickness of the sprayed layer 20 around it.

Another spray coating layer 50 is disposed on the surface of the above-mentioned antenna metal layer 40 and the surrounding sprayed layer 20 (as shown in FIG. 24). As such, the recoated coating layer 50 effectively shields the antenna metal layer 40 on the substrate, resulting in a flat appearance.

As in the foregoing embodiment, the step of electroless plating may be performed before the first sprayed layer 20 is sprayed.

A practical application example of the third embodiment will be described below in which a contact is formed on the other side (back side) of the substrate for grounding or signal feeding and feeding of the antenna.

In the method according to the invention, a non-platable plastic (e.g. polycarbonate) is used as the substrate 10 during the first molding. In the present case, the contact is provided on a protrusion 61 on the back side (as shown in Fig. 25). A recessed region 11 is formed in the region of the substrate 10 where the antenna, the contact, and the communication path of the two are to be formed, as shown in FIG.

A second molding is then performed on the substrate 10, i.e., a plateable plastic is cast into the recessed region 11 to form a plateable plastic region 12, and a through hole 60 is formed in the moldable plastic region 12. Preferably, the through hole has a funnel shape (or a tapered shape) whose outer diameter is the largest on the back surface of the substrate 10. In the above-described steps, a spraying operation is performed on the plastic plated region 12 on the front side of the substrate 10 to form a sprayed layer 20 (refer to Fig. 26). The portion of the sprayed layer 20 corresponding to the antenna pattern is removed by laser engraving such that the underlying plateable plastic molding substrate is exposed, as shown in Figure 27. Then, electroless plating is performed to form a metal layer on the surface of the communication path between the antenna, the contact and the antenna and the contact (as shown in FIG. 28), and the metal layer includes the antenna 40, the contact 42, and the communication path between the two. 41.

Finally, another spray coating layer 50 is further disposed on the surface of the sprayed metal layer 40 and the surrounding sprayed layer 20 (as shown in FIG. 29). As such, the recoated coating layer 50 effectively shields the antenna metal layer 40 on the substrate, resulting in a flat appearance.

As described above, the description of the antenna process is used as an explanation. However, the present invention can also be applied to the process of a general circuit. Therefore, the process of fabricating an antenna and a circuit on a substrate and forming a flat appearance is within the scope of the present invention.

In the method of the present invention, before the antenna is fabricated, a layer of material is sprayed on the area where the antenna is to be formed, and the thickness of the sprayed layer is equivalent to the thickness of the antenna metal layer to be formed later, and then the laser engraving is used to remove the corresponding antenna. The sprayed layer of the map is formed by electroless plating on the antenna pattern to form an antenna metal layer. The antenna metal layer and the sprayed layer are both of equal thickness, and then a second sprayed layer is coated to effectively shield the antenna metal layer, thereby naturally producing a flat appearance. And present a beautiful texture, which is impossible to achieve by conventional technology. In this case, the laser engraving method is used to directly sculpt the antenna pattern to be formed on the sprayed layer. Therefore, whenever the shape of the antenna is changed, only the path of the laser engraving needs to be adjusted, and it is not necessary to separately manufacture or modify the injection mold. Effectively shortens the time required to adjust the antenna configuration.

In summary, the humanized design of this case is quite in line with actual needs. The specific improvement of the existing defects is obviously a breakthrough improvement advantage compared with the prior art, and it has an improvement in efficacy and is not easy to achieve. The case has not been disclosed or disclosed in domestic and foreign literature and market, and has complied with the provisions of the Patent Law. The detailed description above is a detailed description of one of the possible embodiments of the present invention, and the embodiment is not intended to limit the scope of the patents, and the equivalent implementations or modifications that are not included in the spirit of the present invention should be included in The patent scope of this case.

10. . . Substrate

11. . . Sag area

12. . . Plastic plated area

20. . . Spray coating

30. . . Leiguan District

40. . . Antenna metal layer

41. . . Connected path

42. . . contact

50. . . Spray coating

60. . . Through hole

61. . . Protruding

62. . . Laser activation zone

Figure 1 is a perspective view showing the spraying step in the first embodiment of the present invention.

Figure 1B is a cross-sectional view of Figure A.

Fig. 2 shows a laser engraving step of the first embodiment of the present invention.

Figure 3 shows the electroless plating step of the first embodiment of the present invention.

Figure 4 shows the secondary spraying step of the first embodiment of the present invention.

Fig. 5A is a perspective view showing the structure of a substrate of an application example of the first embodiment of the present invention.

Figure 5B is a cross-sectional view of Figure 5A.

Fig. 6 shows a spraying step of an application example of the first embodiment of the present invention.

Fig. 7 shows a laser engraving step of an application example of the first embodiment of the present invention.

Fig. 8 shows a laser activation step of an application example of the first embodiment of the present invention.

Figure 9 is a diagram showing the steps of forming an antenna (or circuit), a contact, and both of the application examples of the first embodiment of the present invention.

Figure 10 shows a second spraying step of an application example of the first embodiment of the present invention.

Figure 11A is a perspective view showing the spraying step in the second embodiment of the present invention, in which the right side is a cross-sectional view.

Figure 11B is a cross-sectional view of Figure 11A.

Figure 12 shows the laser engraving step of the second embodiment of the present invention.

Figure 13 shows the electroless plating step of the second embodiment of the present invention.

Figure 14 shows a second spraying step of the second embodiment of the present invention.

Fig. 15A is a perspective view showing the structure of a substrate of an application example of the second embodiment of the present invention.

Figure 15B is a cross-sectional view of Figure 15A.

Figure 16 shows a spraying step of an application example of the second embodiment of the present invention.

Fig. 17 shows a laser engraving step of an application example of the second embodiment of the present invention.

Figure 18 is a diagram showing the steps of forming an antenna (or circuit), a contact, and both of the communication paths of the application example of the second embodiment of the present invention.

Fig. 19 shows a second spraying step of the application example of the second embodiment of the present invention.

Fig. 20A is a perspective view showing the structure of a substrate of a third embodiment of the present invention.

Figure 20B is a cross-sectional view of Figure 20A.

Figure 21 shows a secondary mold and a single spraying step of a third embodiment of the present invention.

Figure 22 shows the laser engraving step of the third embodiment of the present invention.

Figure 23 shows the electroless plating step of the third embodiment of the present invention.

Figure 24 shows a second spraying step of the third embodiment of the present invention.

Fig. 25 shows a substrate structure of an application example of the third embodiment of the present invention.

Fig. 26 shows a secondary mold and a single spraying step in the application example of the third embodiment of the present invention.

Fig. 27 shows a laser engraving step of an application example of the third embodiment of the present invention.

Fig. 28 shows a communication path forming step of an antenna (or circuit), a contact, and both of the application examples of the third embodiment of the present invention.

Fig. 29 shows a second spraying step of the application example of the third embodiment of the present invention.

10. . . Substrate

12. . . Plastic plated area

20. . . Spray coating

40. . . Antenna metal layer

50. . . Spray coating

Claims (6)

A method for manufacturing a circuit casing by spraying and laser engraving comprises the steps of: taking a substrate; wherein the substrate is required to be electrolessly plated after being activated by laser light; applying a spray coating layer on the substrate The thickness of the sprayed layer is approximately equal to the thickness of the circuit metal layer to be formed later; applying a laser engraving to remove the sprayed layer corresponding to the circuit pattern, so that the underlying molding substrate is exposed to form a lightning engraving area In the laser carving area, the substrate is activated by laser light; a metal layer is formed on the lightning-etching area by electroless plating; the thickness of the circuit metal layer formed by electroless plating is approximately equal to the thickness of the sprayed layer; The surface of the circuit metal layer and the surrounding sprayed layer are further coated with another sprayed layer; thus, the sprayed sprayed layer can effectively shield the circuit metal layer on the substrate to produce a flat appearance. A method of manufacturing a casing having a circuit by spraying and laser engraving, as in claim 1, wherein the circuit is an antenna circuit. A method for manufacturing a circuit casing by spraying and laser engraving comprises the steps of: using a non-platable plastic as a substrate during the first molding, wherein a recessed region is formed on a substrate on a region where the circuit is to be formed; Performing a second molding on the substrate, that is, casting plastic in the recessed area to form a plasticizable region; coating the substrate (including the plasticizable region) with a spray coating; Laser engraving, removing the sprayed layer corresponding to the circuit pattern in the platable plastic zone, such that the injection molded substrate formed by the underlying platable plastic is exposed to form a ray-engraving zone; and by electroless plating, A metal layer as a circuit is formed on the laser engraving area. A method for manufacturing a circuit casing by spraying and laser engraving according to the third aspect of the patent application, wherein the non-platable plastic is polycarbonate (PC), and the pliable plastic is acrylonitrile-butadiene. - Acrylonitrile-Butadiene-Styrene copolymers (ABS) or a mixture of ABS and PC. A method of manufacturing a casing having a circuit by spraying and laser engraving, as in claim 3, wherein the circuit is an antenna circuit. A method of manufacturing a casing having a circuit by spraying and laser engraving, as in claim 3, wherein the step of electroless plating is performed before the first sprayed layer is sprayed.