JP6097026B2 - Structure and manufacturing method of structure - Google Patents

Description

  The present invention relates to a structure provided with a conductive pattern and a method for manufacturing the structure.

  As a technique for forming a conductive pattern that passes through a through-hole on a molded product having a through-hole, for example, there is an LDS (Laser Direct Structure) method using light (laser) irradiation (Non-patent Document 1).

  In the LDS method, the resin surface is partially activated by irradiating the resin surface with a laser, and the activated portion is plated to form a conductive pattern. Here, there is a limit to the effective incident angle of the laser with respect to the resin, and it is necessary to irradiate the laser below the effective incident angle (the effective incident angle is caused by the resin material and the laser output, but is generally about 70 °, (If mass production quality is taken into consideration, it is about 60 °). Therefore, in order to successfully irradiate the laser into the through hole, the inner wall of the through hole needs to be inclined so as to spread toward at least one opening. For example, Non-Patent Document 1 includes a conical (cone-shaped) through hole as shown in FIG. 8A and a shape in which the tops of two cones as shown in FIG. A (double cone type) through hole is described.

  Patent Document 1 describes a technique for forming a conductive pattern in a through hole by exposure instead of the LDS method. Also in the technique described in Patent Document 1, the inner wall of the through hole is inclined so as to spread from the narrowest part to the opening.

JP-A-11-97809 (published on April 9, 1999)

LPKF, "Designing three-dimensional circuitry bodies (MIDs)", acquired on June 7, 2012 from http://www.lpkfusa.com/mid/lasersystems.htm

  The thickness of the molded product on which the conductive pattern is formed may need to be increased for the purpose of abutting on another structure for position regulation or the like, or for connecting the wiring to a circuit board or the like. . Here, in the case where the conductive pattern is formed by light irradiation, in order to irradiate light up to the inner part of the through hole, the inner wall of the through hole needs to have an inclination. Will also increase in diameter (FIGS. 8C and 8D). When the hole diameter of the opening is increased, the area for forming the conductive pattern is narrowed, and the degree of freedom in pattern design is reduced.

  The present invention has been made in view of the above problems, and has as its main object to provide a technique for improving the degree of freedom in designing a conductive pattern when a conductive pattern is formed on a molded article by light irradiation. To do.

  In order to solve the above problems, a structure according to the present invention includes a molded article having a through hole, and a conductive pattern provided on the molded article by light irradiation and passing through the through hole. The pattern forming region on the inner wall of the through hole has a slope, and the slope is stepwise or continuous from the narrowest portion of the through hole toward at least one opening. It is characterized by being steep.

  According to the above configuration, it is possible to effectively irradiate light to the inner part of the through hole by making the inclination angle in the inner part (near the narrowest part) of the through hole gentle, and the one opening described above. By making the inclination angle in the vicinity of the part steeper than that in the back part, the hole diameter of the one opening part can be reduced, and the degree of freedom in designing the conductive pattern can be improved. In addition, since the hole diameter of the one opening is reduced, the pattern length of the conductive pattern can be shortened.

  In the structure according to the present invention, in the entire pattern formation region of the inner wall of the through hole, the minimum incident angle when passing through any opening of the through hole is equal to or less than the effective incident angle of the light irradiation. It is preferable that the inclination is set.

  According to the above configuration, the entire pattern formation region 4 on the inner wall of the through hole can be successfully irradiated with light at an effective incident angle or less, so that the conductive pattern 3 can be suitably formed by light irradiation.

  The structure according to the present invention includes a molded product having a through hole and a conductive pattern provided on the molded product by light irradiation and passing through the through hole, and the conductive material on the inner wall of the through hole. In the pattern formation region where the pattern is provided, a first inclined portion, a flat portion, and a second inclined portion are provided in this order from the narrowest portion of the through hole toward at least one opening portion. The two inclined portions may be steeper than the first inclined portion.

  According to said structure, while making the inclination | tilt angle of the 1st inclination part in the back part (nearest narrow part) of a through-hole gentle, light irradiation can be effectively performed also about the back part of a through-hole. Even if a flat part is provided between the first inclined part and the second inclined part by making the inclination angle of the second inclined part in the vicinity of the one opening part steeper than the back part, By reducing the hole diameter of one of the openings, the degree of freedom in designing the conductive pattern can be improved.

  The structure manufacturing method according to the present invention is a structure manufacturing method according to the present invention, and includes a light irradiation step of irradiating the molded product with light.

  According to said method, since a conductive pattern can be formed suitably by performing light irradiation, the structure which concerns on this invention can be manufactured.

  In the structure manufacturing method according to the present invention, it is preferable that the light irradiation step irradiates light having different incident angles with respect to the openings of the through holes.

  According to the above method, by performing light irradiation in accordance with the inclination of each part of the through hole, it is possible to successfully irradiate the entire pattern forming region 4 with an effective incident angle or less.

  According to the present invention, the hole diameter of the opening can be reduced and the degree of freedom in designing the conductive pattern can be improved.

It is side sectional drawing which shows the example of the structure which concerns on one Embodiment (Embodiment 1) of this invention. It is a schematic diagram which shows the example of the range of the through-hole in a molded article, and the hole diameter of each opening part. It is a schematic diagram which shows the variation of the pattern formation area which concerns on one Embodiment of this invention. It is a schematic diagram explaining an example of the inclination of the pattern formation area which concerns on one Embodiment of this invention. It is side sectional drawing which shows the example of the structure which concerns on one Embodiment (Embodiment 2) of this invention. It is a schematic diagram which shows the other example of the range of the through-hole in a molded article, and the hole diameter of each opening part. It is side sectional drawing which shows the example of the structure which concerns on one Embodiment (Embodiment 3) of this invention. It is side sectional drawing which shows the example of the structure which concerns on a prior art. It is a schematic diagram explaining the effective incident angle in light irradiation.

Embodiment 1
FIG. 1 is a side sectional view showing an example of a structure according to an embodiment (Embodiment 1) of the present invention. As shown in FIG. 1, the structure 10 according to the present embodiment includes a molded product 2 having a through hole 1 and a conductive pattern 3 provided on the molded product 2 by light irradiation and passing through the through hole 1. The pattern forming region 4 where the conductive pattern 3 is provided on the inner wall of the through hole 1 has an inclination, and the inclination is an opening from the opening (narrowest part) 5 of the through hole 1. It becomes steep (step (FIG. 1 (a)) or continuous (FIG. 1 (b)) steeply toward 6 (the inclination is closer to the vertical).

(Molded product)
In the present specification, the molded product means an insulating resin structure molded into an arbitrary shape using a mold or the like. Although the shape of the molded product 2 is not particularly limited, it may have a flat plate shape or a curved plate shape whose thickness becomes substantially constant by offsetting the shape of the surface on one side of the molded product 2 in processing. However, the molded product 2 may have a portion that is thicker (thicker) than other portions in order to regulate the position of other structures. The shape of the molded product may be partially recessed to make it substantially constant with the surroundings (in mold terms this technique is called meat stealing).

  The molded product 2 is provided with a through hole 1 that penetrates the molded product 2 in the thickness direction. For convenience of explanation, the surfaces of the molded product 2 where the through holes 1 open are referred to as the front surface 7 and the back surface 8.

(Conductive pattern)
In this specification, the conductive pattern means a film-like or plate-like conductor formed in an arbitrary shape. The conductive pattern 3 is provided on the molded product 2 by a processing method involving light irradiation, which will be described later, and extends from the front surface 7 to the back surface 8 of the molded product 2 through the through hole 1. The substance which comprises the conductive pattern 3 is not specifically limited, What is necessary is just to use the substance (for example, metal) which has electroconductivity.

  In one aspect, the conductive pattern 3 can be formed using an LDS method as described in Non-Patent Document 1. That is, an organic metal is mixed with the resin constituting the molded product 2, and the region on the molded product 2 where the conductive pattern 3 is formed is irradiated with laser, thereby depositing plating on the laser irradiated portion or the laser irradiated portion. As a result, the plating is bonded to the laser irradiation portion, and the conductive pattern 3 can be formed.

  In another aspect, the conductive pattern 3 can be formed using an exposure method as described in Patent Document 1. That is, after a conductive film is formed on the molded product 2 by a known method, a photo-curing resist is laminated, exposed (light irradiation) using a mask, and developed and etched to form the conductive pattern 3. Can be formed.

  As described above, the conductive pattern 3 can be formed in a desired shape by performing light irradiation (including laser irradiation) on the molded product 2.

  Note that light irradiation (including laser irradiation) needs to be performed at an effective incident angle or less. FIG. 9 is a schematic diagram for explaining an effective incident angle.

  FIG. 9A shows a case where light is irradiated on a flat surface. As shown in FIG. 9A, it is most effective to irradiate light on the flat surface from the vertical direction with little reflection, or even in the oblique direction, the object is irradiated from the vertical line. Effective light irradiation can be performed from a direction up to a different effective incident angle depending on a certain molding.

  Moreover, FIG.9 (b) shows the case where light is irradiated with respect to an inclined surface. As described above, light irradiation from the direction perpendicular to the inclined surface is most effective. However, as shown in FIG. 9B, if the inclined angle is less than the effective incident angle with respect to the inclined surface, Effective light irradiation can be performed even from the outside. However, even if the tilt angle is equal to or greater than the effective incident angle, the irradiation gun itself is changed to irradiate light from an oblique angle, or only the inclined surface portion is irradiated with light by another irradiation gun. It can be carried out.

(Through hole)
In the present specification, the through hole means a hole that penetrates the molded product in the thickness direction. FIG. 2 is a schematic diagram showing an example of the range of the through hole 1 and the hole diameter of each opening in the molded product 2. In the figure, the hatched portion indicates the through hole 1, the hole diameter X indicates the hole diameter of the opening 5 on the front surface 7 side, and the hole diameter Y indicates the hole diameter of the opening 6 on the back surface 8 side. Corners A and B indicate both ends defining the hole diameter Y.

  2A and 2B show a case where the through hole 1 is provided in the flat plate-like portion of the molded product 2. FIG. 2B shows a case where one corner B of the through hole 1 is rounded on the opening 6 side. In this case, as shown in FIG. 2B, a hole diameter Y is defined between a virtual point B ′ extending from the inner wall of the through hole 1 and the corner A. Although the corner B side is rounded for convenience, the hole diameter Y is defined similarly even when the corner A side is rounded. FIG. 2C shows a case where the through hole 1 is provided in the curved plate (arc) -shaped portion of the molded product 2. As shown in FIG. 2 (c), the range of the through hole 1 is a region sandwiched between a surface obtained by offsetting the shape of the surface on one side so that the thickness of the molded product 2 is substantially constant and the surface of the offset source. It is prescribed.

  The shape of each opening of the through hole 1 is not limited, and examples thereof include an ellipse, a polygon (including a triangle and a quadrangle), a circle or a shape in which an ellipse and a polygon are combined, and the like.

  Further, as described above, the pattern formation region 4 where the conductive pattern 3 is provided on the inner wall of the through hole 1 has an inclination, and the inclination is the opening (narrowest part) of the through hole 1. From 5 to the opening 6, it is steep in steps (FIG. 1 (a)) or continuously (FIG. 1 (b)).

  In addition, although the inclination of parts other than the pattern formation area 4 on the inner wall of the through-hole 1 is not specifically limited, it is preferable if it has the same inclination as the pattern formation area 4 because the pattern can be arranged over the entire circumference of the through-hole.

  The region where the pattern formation region 4 is provided on the inner wall of the through hole 1 is not particularly limited as long as it is provided so as to be continuous from the opening 5 to the opening 6, as shown in FIG. 1 and FIG. Alternatively, it may be provided only on one side of the through hole 1 or may be provided on the entire through hole 1 as shown in FIG. Further, as shown in FIG. 3C, the pattern formation region 4 may be provided on the entire circumference only in the vicinity of the narrowest portion (opening portion 5).

  Here, since the inclination of the pattern formation region 4 is set as described above, the following effects can be obtained. It should be noted that the numerical values used in the following description are merely illustrative examples, and those skilled in the art who have contacted this specification will easily understand that they are not intended to limit the scope of the present invention.

  FIG. 4 is a schematic diagram for explaining an example of the inclination of the pattern formation region 4. Here, as an example, the description will be made assuming that the effective incident angle in light irradiation is 60 ° (effective incident angle in consideration of mass production quality in the LDS method), the thickness of the molded product 2 is 2 mm, and the hole diameter X is 0.3 mm. The present invention is not limited to this.

  First, as shown in FIG. 4A, if the inclination of the pattern formation region 4 is set to 75 °, effective light irradiation can be performed also on the inner portion of the through hole 1 (near the opening 5). . This is because the minimum incident angle with respect to the angle C at the back of the through-hole 1 is 59 ° when light is irradiated from the direction of the angle B, so that the light I can be irradiated at an effective incident angle or less. The minimum incident angle refers to an incident angle when the incident angle becomes the lowest when light irradiation is performed from various directions through the opening 6.

  On the other hand, as shown in FIG. 4B, when the inclination of the pattern formation region 4 is 80 °, the hole diameter Y of the opening 6 can be made smaller than in the case of FIG. Effective light irradiation cannot be performed on the inner part of the through hole 1 (in the vicinity of the opening 5). This is because the minimum incident angle with respect to the angle C at the back of the through-hole 1 is 61 ° when light is irradiated from the direction of the angle B, and therefore the light I cannot be irradiated at an effective incident angle or less.

  Here, as shown in FIG. 4 (c), when the inclination near the deep part (narrowest part, opening 5) of the through hole is 75 °, and the inclination is 80 ° steeper at the branch point D, The hole diameter Y of the opening 6 can be made smaller than in the case of FIG. 4A, and effective light irradiation can be performed on the back part of the through hole 1 (near the opening 5). Because the minimum incident angle with respect to the angle C at the back of the through-hole 1 is 59 ° when light is irradiated from the direction of the angle B, the light I 0 can be irradiated at an effective incident angle or less, and This is because the light I1 can be irradiated below the effective incident angle by irradiating the angle above the angle D of the through-hole 1 with more light.

  Further, as shown in FIG. 1B, the same effect can be obtained even when the inclination angle is continuously changed.

  Thus, by setting the inclination in the pattern formation region 4 so that the minimum incident angle through the opening 6 is equal to or less than the effective incident angle in the entire pattern formation region 4, On the other hand, it is possible to successfully irradiate light at an effective incident angle or less. Thereby, the conductive pattern 3 can be formed suitably. In particular, when the inclination is changed in the middle of the through-hole 1, each part of the through-hole 1 is irradiated by irradiating light having different incident angles with respect to the opening 6 of the through-hole 1 so as to adapt to the change in the inclination. Thus, the entire pattern formation region 4 can be successfully irradiated with light at an effective incident angle or less.

  The method of irradiating light with different incident angles with respect to the opening 6 is not particularly limited. For example, light irradiation is performed using an irradiation gun set to change the light irradiation angle mechanically or optically. The incident angle may be changed by rotating the molded article 2 that is the object to be irradiated, and the light irradiation may be performed, or a plurality of irradiation guns having different light irradiation angles are provided. Light irradiation may be performed using an apparatus.

  Then, by changing the inclination of the pattern formation region 4 in the middle so that the inclination becomes steeper from the inner part of the through hole (the narrowest part, the opening part 5) toward the opening part 6, The inclination angle in the back part (near the opening part 5) can be made gentle so that light irradiation can be effectively performed also in the back part of the through hole 1, and the inclination angle in the vicinity of the opening part 6 is made steeper than that in the back part. By reducing the hole diameter Y of the opening 6, the degree of freedom in designing the conductive pattern 3 can be improved.

  Further, since the hole diameter Y is reduced, the pattern length of the conductive pattern 3 can be shortened. In particular, when the conductive pattern 3 has a surface resistance value, the electrical loss in the conductive pattern 3 can be reduced by shortening the pattern length of the conductive pattern 3.

(Use of conductive pattern)
In the present embodiment, the conductive pattern 3 can be used for various applications.

  For example, in one aspect, the conductive pattern 3 can be used as an antenna. That is, the conductive pattern 3 can be used as an antenna by providing the conductive pattern 3 with a feeding portion on the front surface 7 side or the back surface 8 side.

  In another aspect, the conductive pattern 3 can be used to conductively connect the front surface 7 and the back surface 8 of the molded product 2. For example, a ground such as a sheet metal can be disposed on the front surface 7 side and a circuit board can be disposed on the back surface 8 side, and both can be connected via the conductive pattern 3.

  In still another aspect, the conductive pattern 3 may be used for countermeasures against static electricity.

[Embodiment 2]
FIG. 5 is a side sectional view showing an example of a structure according to another embodiment (Embodiment 2) of the present invention. In the structure 10 according to the first embodiment, the through hole 1 has a tapered shape from one opening to the other opening. However, in the structure 20 according to the present embodiment, the through hole 1 has The shape is tapered from both openings toward the narrowest part inside the through hole 1. Since this embodiment is different from the first embodiment only in this point, only the difference will be described below, and the same member number is assigned to the same member, and the description is omitted.

  As shown in FIG. 5, in the present embodiment, the through hole 1 has the narrowest portion 9 inside the through hole 1. In the present specification, the narrowest portion means a position where the cross-sectional area becomes the narrowest when the through hole is cut along a plane perpendicular to the thickness direction of the molded product. Even when the through-hole 1 has such a shape, not only the light irradiation from the back surface 8 side as in the first embodiment but also the light irradiation from the front surface 7 side is successful. It is possible to irradiate the entire pattern forming region 4 with light.

  FIG. 6 shows the range of the through-hole 1 in the molded product 2 and each opening portion when the through-hole 1 has a shape that tapers from both openings toward the narrowest portion 9 inside the through-hole 1. It is a schematic diagram which shows the example of a hole diameter. As in FIG. 2, in the drawing, the hatched portion indicates the through hole 1, the hole diameter X indicates the hole diameter of the opening portion 5 on the front surface 7 side, and the hole diameter Y indicates the hole diameter of the opening portion 6 on the back surface 8 side. Corners A and B indicate both ends defining the hole diameter Y. FIG. 6A shows a case where the through hole 1 is provided in the flat plate-like portion of the molded product 2, and FIG. 6B shows the through hole in the curved plate (arc) shaped portion of the molded product 2. The case where 1 is provided is shown.

  In FIG. 5, only the inclination of the pattern formation region 4 on the back surface 8 side of the through hole 1 is changed, and the inclination of the pattern formation region 4 on the front surface 7 side is not changed, but the pattern formation on the front surface 7 side is changed. The inclination of the region 4 may be changed in the same manner as the back surface 8 side. Thereby, the hole diameter X of the opening 5 on the surface 7 side can also be reduced.

[Embodiment 3]
FIG. 7 is a side sectional view showing an example of a structure according to still another embodiment (Embodiment 3) of the present invention. In the structure 30 according to the present embodiment, a flat portion 4b having no inclination with respect to the front surface 7 and the back surface 8 is provided in the middle of the pattern formation region 4, and an inclined portion (first inclined portion) having an inclination is provided. 4a and inclined part (second inclined part) 4c sandwich this. Since this embodiment is different from the first embodiment only in this point, only the difference will be described below, and the same member number is assigned to the same member, and the description is omitted.

  Here, the inclination angle θ2 of the inclined portion 4c close to the opening 6 is steeper than the inclination angle θ1 of the inclined portion 4a close to the opening (narrowest portion) 5. Therefore, even if the flat portion 4b is provided in the middle of the pattern formation region 4, the hole diameter Y of the opening 6 can be reduced by making the inclination angle θ2 of the inclined portion 4c steep. Can do. Thereby, the same effect as Embodiment 1 can be acquired. However, the first embodiment in which the flat portion 4b does not exist is preferable because the hole diameter Y can be further reduced.

  The present invention can be used in the field of manufacturing electronic devices.

DESCRIPTION OF SYMBOLS 1 Through-hole 2 Molded product 3 Conductive pattern 4 Pattern formation area 4a Inclination part (1st inclination part)
4b flat part 4c inclined part (second inclined part)
5 opening (narrowest part)
6 Opening 7 Front 8 Back 9 Narrowest 10, 20, 30 Structure

Claims (4)

A molded article having a through hole;
A conductive pattern provided on the molding by light irradiation and passing through the through-hole, and
In the pattern formation region provided with the conductive pattern on the inner wall of the through hole, it has an inclination,
In the pattern formation region, between the narrowest portion of the through hole and one opening of the through hole, a first region, a second region closer to the one opening than the first region, Is included,
The slope in the second region is steeper than the slope in the first region;
Light incident on the first region at an effective incident angle equal to or smaller than the effective incident angle is incident on the second region beyond the effective incident angle, and incident on the second region at the effective incident angle or less. The structure is characterized in that the inclination is set so that light is blocked by the molded product at the periphery of the one opening and does not enter at least a part of the first region .   In the pattern formation region of the inner wall of the through hole, the inclination is set so that the minimum incident angle when passing through any opening of the through hole is equal to or less than the effective incident angle of the light irradiation. The structure according to claim 1. It is a manufacturing method of the structure according to claim 1 or 2 ,
The manufacturing method of the structure characterized by including the light irradiation process of irradiating the said molded object with light. 4. The method of manufacturing a structure according to claim 3 , wherein, in the light irradiation step, irradiation with a plurality of lights having different incident angles with respect to the opening of the through hole is performed.

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