SELECTIVE PLATING MASK MEMBER AND SELECTIVE PLATING METHOD

Abstract

There are provided a selective plating mask member including: a drum-shaped jig having a jig opening arrangement region which is a region having a jig opening portion that communicates an outer side surface with an inner side surface of the drum-shaped jig, that is a strip shaped recess provided along a circumferential direction on the outer side surface; and a mask that embeds the jig opening arrangement region and has a mask opening at a location corresponding to the jig opening, wherein the mask is placed in the jig opening arrangement region, a through hole composed of the jig opening and the mask opening is provided, and an edge of the mask opening is raised toward outside of the drum-shaped jig, and there is provided a related technique thereof.

Claims

1. A selective plating mask member, comprising: a drum-shaped jig having a jig opening arrangement region which is a region having a jig opening portion that communicates an outer side surface with an inner side surface of the drum-shaped jig, that is a strip shaped recess provided along a circumferential direction on the outer side surface; and a mask that embeds the jig opening arrangement region and has a mask opening at a location corresponding to the jig opening, wherein the mask is placed in the jig opening arrangement region, a through hole composed of the jig opening and the mask opening is provided, and an edge of the mask opening is raised toward outside of the drum-shaped jig.

2. The selective plating mask member according to claim 1, wherein at least the edge of the mask opening of the mask is made of rubber.

3. The selective plating mask member according to claim 1, wherein in the jig opening arrangement region, a plurality of the jig openings are placed along the circumferential direction.

4. The selective plating mask member according to claim 1, wherein in the drum-shaped jig, the jig openings are placed in a predetermined pattern, and the mask has a plurality of parts lined up each having n mask units (n is a natural number) corresponding to pattern units of the predetermined pattern.

5. The selective plating mask member according to claim 1, wherein the jig opening arrangement region is a recess provided in a strip shape around an entire circumference of the drum-shaped jig, that is, on an outer side surface of the drum-shaped jig.

6. The selective plating mask member according to claim 1, wherein a plurality of rows of combinations of the jig opening arrangement region and the mask are placed in a vertical direction of the drum-shaped jig.

7. The selective plating mask member according to claim 1, wherein in the drum-shaped jig, the jig opening arrangement region includes: a non-penetrating groove; and a relatively convex region, wherein a back side of the mask has a shape that fits into the groove and the relatively convex region.

8. The selective plating mask member according to claim 1, wherein the mask opening coincides with the jig opening or at least selectively covers the jig opening.

9. A selective plating method, comprising: bringing a plating solution into contact with a workpiece through the through hole, the workpiece being wrapped around the selective plating mask member according to claim 1; and applying plating to the workpiece.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG. 1 is a schematic top perspective view of a drum-shaped jig.

[0034] FIG. 2 is a schematic cross-sectional view of a portion of a selective plating device taken along a horizontal plane.

[0035] FIG. 3A is a schematic front view of the selective plating mask member according to a first embodiment.

[0036] FIG. 3B is a schematic cross-sectional view taken along line AA of FIG. 3A.

[0037] FIG. 4A is a schematic front view of a selective plating mask member according to the second embodiment (Example 1).

[0038] FIG. 4B is a schematic cross-sectional view taken along line AA of FIG. 4A.

[0039] FIG. 4C is a schematic front view of a drum-shaped jig according to the second embodiment (Example 1).

[0040] FIG. 5 is a schematic front view of a selective plating mask member according to a third embodiment.

[0041] FIG. 6 is a photograph showing an appearance of the selective plating applied to a workpiece obtained in Comparative example 1.

[0042] FIG. 7 is a photograph showing an appearance of the selective plating applied to a workpiece obtained in Example 1.

DETAILED DESCRIPTION OF THE INVENTION

[0043] The present embodiment will be described below. - indicates a value greater than or equal to a given value and less than or equal to a given value.

Selective Plating Mask Member

[0044] The present embodiment provides a selective plating mask member including: [0045] a drum-shaped jig 11 having a jig opening arrangement region 17 which is a region having a jig opening portion 13 that communicates an outer side surface 16 with an inner side surface of the drum-shaped jig 11, that is a strip shaped recess provided along a circumferential direction on the outer side surface 16; and [0046] a mask 31 that embeds the jig opening arrangement region 17 and has a mask opening 32 at a location corresponding to the jig opening 13, [0047] wherein the mask 31 is placed in the jig opening arrangement region 17, [0048] a through hole composed of the jig opening 13 and the mask opening 32 is provided, and [0049] an edge 33 of the mask opening 32 is raised toward outside of the drum-shaped jig 11.

[0050] An overall mechanism of the selective plating mask member according to the present embodiment and the selective plating device into which the selective plating mask member is incorporated will be described.

[0051] In this specification, the directions are defined as follows.

[0052] An upward direction is the Z direction, and a downward direction is the Z direction.

[0053] A radial direction from a circumference to a center is defined as the Y direction, and an opposite direction is defined as the-Y direction, which are perpendicular to the Z direction. The Y direction is also the direction from the outside to the inside of the drum-shaped jig 11, and is therefore also called an inward direction (when viewed from front). The Y direction is also the direction from the inside to the outside of the drum-shaped jig 11, and is therefore also called an outward direction (when viewed from behind).

[0054] The directions perpendicular to the Z and Y directions are the X direction as a right direction and the X direction as a left direction, respectively, when viewed in the Y direction (viewed from the front).

[0055] A top-bottom direction is the Z direction, and a horizontal plane is constituted of the X and Y directions.

[0056] The above directions are shown in each drawing of the present application.

[0057] As shown in FIG. 1, a drum-shaped jig 11 constituting the selective plating mask member according to the present embodiment has two annular bottom portions 14 and 15 placed one above the other (top-bottom direction). As shown in FIG. 2, in the selective plating device according to the present embodiment, a strip-shaped metal material (referred to as a workpiece 1 hereinafter) unwound from an unwinding device (not shown) is conveyed in a direction of the arrow shown in FIG. 2 by tension applied by the winding device (not shown). The thickness direction of the workpiece 1 lies within a horizontal plane. Also, a radial direction of the drum-shaped jig 11 is within a horizontal plane.

[0058] The workpiece 1 is redirected in its travel direction by an inlet side support roll 61, and is wound around the drum-shaped jig 11 in close contact with a mask 31 (described later) that is disposed on the outer surface side 16 of the drum-shaped jig 11. Thereafter, the workpiece 1 is wound around again by an outlet side support roll 62 and wound up.

[0059] The drum-shaped jig 11 is a cylindrical jig that conveys the workpiece 1 along its outer circumference while the workpiece 1 is in close contact with its side surface. A positioning pin 12 is provided on the side surface of the drum-shaped jig 11, and the position of the workpiece 1 on the drum-shaped jig 11 is fixed by fitting the positioning pin 12 into a guide hole formed in the workpiece 1. Then, when the position of the workpiece 1 is fixed, the jig opening 13 is formed on the side surface of the drum-shaped jig 11 so that an intended terminal position (i.e., a location to be plated, the selective plating area) and the jig opening 13 overlap on each other at the same position.

[0060] The workpiece 1 may be conveyed in a direction of the arrow shown in FIG. 2 while being pressed against the side surface of the drum-shaped jig 11 by a rubber pressure belt 22 attached to a belt mechanism 21 installed outside the drum-shaped jig 11.

[0061] The plating solution is pumped by a pump (not shown) into a plating solution jet cell 23 installed inside the drum-shaped jig 11, and is ejected from a plating solution ejection slit 24 which also serves as an anode, and is supplied toward the outside of the drum-shaped jig 11 through the jig opening 13 of the drum-shaped jig 11.

[0062] When the workpiece 1 is attached to the drum-shaped jig 11 and the selective plating mask member 50 which is composed of the mask 31 placed in the jig opening arrangement region 17 of the drum-shaped jig 11 described later, a plating solution is supplied to a surface portion of the workpiece 1 corresponding to the through hole composed of the jig opening 13 and the mask opening 32 of the mask 31.

[0063] The plating solution is continuously supplied to the plating solution jet cell 23 by a pump, and the plating solution accumulated in the plating solution jet cell 23 is ejected vigorously from the plating solution ejection slit 24.

[0064] In this manner, the plating solution is ejected onto the workpiece 1 while the workpiece 1 is being conveyed, and the workpiece 1 is selectively plated (selective plating). After plating, the workpiece 1 is washed with water and then dried with hot air or the like as a post-treatment.

[0065] In the selective plating mask member according to the present embodiment, the through hole composed of the jig opening 13 and the mask opening 32 (described later) serves as a plating solution supply port. The plating solution is supplied in a direction from the inside of the drum-shaped jig 11 to the outside of the drum-shaped jig 11. A portion (also called a spot) of the workpiece 1 exposed from the plating solution supply port is selectively plated (selective plating).

[0066] The plating solution supplied to the jig opening 13 (plating solution supply port) finally falls downward and is recovered in a plating solution tank (not shown) provided at a bottom of the drum-shaped jig 11. However, the recovered plating solution may be circulated using a plating solution recovery device (not shown) such as a pump, and may be reused for selective plating.

[0067] There is no limit in the material and shape of the workpiece 1, so long as it can be wrapped around the outer side surface 16 of the selective plating mask member and it enables the above-described selective plating. The material of the workpiece 1 is preferably copper, a copper alloy such as brass, or an iron alloy such as ordinary steel, special steel, or stainless steel, and the workpiece 1 is preferably in the form of a strip (strip or coil) or a plate. The plate thickness of the workpiece 1 can be appropriately selected depending on an application, and is preferably about 0.1 to 3.0 mm, and may be 0.8 mm or less.

[0068] The selective plating is applied to an electronic material such as a connector and terminal, but in the present embodiment, there is no limit in the type of metal used for selective plating. The metal used for selective plating of the electronic materials is usually expensive noble metal such as gold (Au) and silver (Ag), but prior to these selective plating, the strip-shaped workpiece 1 may be underplated with metal such as nickel and copper, over its entire or part of the surface. This underplating and selective plating can be performed in succession, by connecting a reel-to-reel type underplating facility with the selective plating device according to the present embodiment.

[0069] The selective plating mask member according to the present embodiment will be described in detail below.

[0070] The drum-shaped jig 11, which is a component of the selective plating mask member in the present embodiment, is not limited to a specific material or shape, for example, as long as it can be used for the same purpose as the drum-shaped jig 11 described in Patent document 2. Examples of materials include insulating polyvinyl chloride, PPS (polyphenylene sulfide) resin, and other engineering plastics. As one example of the configuration, the drum-shaped jig 11 has two annular (or disk-shaped) upper bottom portion 14 and lower bottom portion 15, and a cylindrical side surface formed by a cylindrical member sandwiched between the two bottom portions 14, 15.

[0071] The drum-shaped jig 11 constituting the selective plating mask member 50 according to the first embodiment shown in FIGS. 3A and 3B, has one (row of) jig opening arrangement regions 17 which are recessed (relative to the outer side surfaces 16 (side edge portion 18) of the cylindrical member) and provided in a strip shape along the circumferential direction on the outer side surfaces 16 of the cylindrical member. A part of this jig opening arrangement region 17 is formed by a jig opening 13 that communicates with the outer side surface 16 and the inner side surface of the cylindrical member. Further, the portion of the outer side surface 16 of the cylindrical member other than the jig opening arrangement region 17 is defined as a side edge portion 18.

[0072] When the jig opening arrangement region 17 is provided in a strip shape so as to be recessed relative to an entire circumference of the drum-shaped jig 11, this leads to an increase in the region in which the jig opening 13 can be secured, and is preferable. The first to third embodiments of the present invention show such a case for example. On the other hand, the jig opening arrangement region 17 may be recessed on only a part of the circumference, rather than the entire circumference. In other words, a part of the circumference may not be recessed, that is, a start point and an end point may be provided to the strip-like recess.

[0073] FIGS. 3A and 3B show the selective plating mask member of the first embodiment, in which a plurality of jig openings 13 are placed in one row along the circumferential direction in the jig opening arrangement region 17 of the drum-shaped jig 11. As another embodiment of the present invention, one jig opening 13 may be provided along the circumferential direction.

[0074] FIGS. 4A to 4C show a case in which the selective plating mask member of the second embodiment has two adjacent rows of jig opening arrangement regions 17 in a vertical direction of the drum-shaped jig 11. The portions where two adjacent rows of the jig opening arrangement regions 17 come into contact with each other are indicated by dashed line in FIG. 4C. Of course, the number of rows may be more than two. In the examples of FIGS. 4A to 4C, in the upper and lower jig opening arrangement regions 17, upper and lower jig openings 13 are designed to be placed in a staggered manner alternately by forming the jig openings 13 at the center of the circumferentially aligned square relatively convex regions 41, at intervals in the circumferential (horizontal) direction and so as to be shifted vertically.

[0075] In the second embodiment, two rows of jig opening arrangement regions 17, which are recesses, are formed adjacent to each other in the vertical direction. Therefore, the two rows of jig opening arrangement regions 17 are one row of strip-like recessed regions (hole region 170 consisting of two rows of adjacent jig opening arrangement regions 17) wide in the vertical direction on the outer side surface 16 of the cylindrical member of the drum-shaped jig 11, and the outer side surface 16 of the drum-shaped jig 11 is not exposed between the two rows of jig opening arrangement regions 17. Therefore, due to a shape corresponding to the recess of the recessed region (hole region 170) in which the jig opening arrangement region 17 is provided, the mask 31 (embedding the hole region 170) placed in the hole region 170 (consisting of two rows of adjacent jig opening arrangement regions 17) appears to have one row of wide shape (strip shape) along the circumferential direction, as shown in FIG. 4A, when viewed from the front.

[0076] In the upper and lower jig opening arrangement regions 17, depending on the selective plating area of the workpiece 1, the jig openings 13 may or may not be placed vertically. When they are not placed vertically, the jig openings 13 in the upper row and the jig openings 13 in the lower row may be placed in a staggered manner alternately in the circumferential direction as shown in FIGS. 4A to 4C.

[0077] As shown in FIGS. 4A to 4C, in the drum-shaped jig 11 that constitutes the selective plating mask member 50, it is preferable that the jig opening arrangement region 17 has a non-penetrating groove 42 (a bottom surface of the groove 42 corresponds to, for example, a bottom surface of the recessed region) and a relatively convex region 41 (formed by the groove 42), and a back surface of the mask 31 has a shape that fits into the groove 42 and the relatively recessed region 41. This configuration improves the fit between the drum-shaped jig 11 and the mask 31. The relatively convex region 41 in FIG. 4C is more recessed than the outer side surface 16. A method for realizing this shape includes, for example, cutting the outer surface side 16 of the drum-shaped jig 11 by a machining treatment or the like, and thereafter cutting the groove 42 by a machining treatment or the like.

[0078] As shown in FIGS. 4A to 4C, when the drum-shaped jig 11 has two adjacent rows of jig opening arrangement regions 17 in the vertical direction, it is preferable to have protrusions and grooves extending in the circumferential direction of the cylindrical member between the upper and lower jig opening arrangement regions 17. Also, it is preferable that the back surface of the mask 31 (i.e., the surface that contacts the drum-shaped jig 11) has a configuration that fits with the protrusions and grooves in the drum-shaped jig 11 (i.e., corresponding grooves and protrusions). This configuration improves the fit between the drum-shaped jig 11 and the mask 31.

[0079] It is preferable that the protrusions and grooves in the drum-shaped jig 11 be provided in one row of jig opening arrangement region 17, in addition to being formed over the circumference of the cylindrical member between the upper and lower jig opening arrangement regions 17.

[0080] As a specific example using one row of jig opening arrangement regions 17: in the jig opening arrangement region 17 which is a recess as shown in FIGS. 4A to 4C, the groove 42 (not penetrating) may be provided so that two rows of relatively convex regions 41 (the above protrusions) when viewed from the front are placed in the vertical direction, and two rows of another rectangular (e.g., rectangular elongated in the vertical direction) relatively convex regions 41 are placed in the circumferential direction of each of the two rectangles (e.g., the left side when viewed from the front). The groove 42 may be referred to as a relatively recessed region with respect to the relatively convex region 41.

[0081] As described above, in FIGS. 4A to 4C, the relatively convex region 41 extending in the circumferential direction is provided between the two rows of jig opening arrangement regions 17. Grooves 42 may be provided above and below the relatively convex region 41. The groove 42 adjacent to the relatively convex region 41 corresponds to the protrusion and groove extending over the circumferential direction of the cylindrical member between the upper and lower jig opening arrangement regions 17.

[0082] In FIGS. 4A to 4C, the mask 31 is placed in the two rows of jig opening arrangement regions 17 (covered with the mask 31), respectively, and the circumferentially extending relatively convex region 41 is also embedded (covered with mask 31). It is preferable that the grooves 42 be formed finely (in other words, the number of relatively convex regions 41 and grooves 42 is increased) so as to suppress the displacement of the mask 31 when the conveyed workpiece 1 rubs against the drum-shaped jig 11.

[0083] As shown in FIGS. 4A to 4C, in the upper row of jig opening arrangement regions 17, the jig opening 13 can be provided at the center of a relatively convex region 41 (approximately square in the example of FIG. 4C) on the center side in the vertical direction of the side surface of the drum-shaped jig 11. The height of each relatively convex region 41 is lower than the side edge portion 18. The heights of the relatively convex regions 41 may be the same or may be different. Each relatively convex region 41 is embedded (covered with the mask 31) when the mask 31 is placed.

[0084] There is no limit in the number of jig openings 13. When a plurality of jig openings 13 are placed in one row along the circumferential direction, all jig openings 13 may or may not be placed in a fixed pattern. The pattern here refers to a pattern consisting of the jig opening 13 and other parts (each relatively convex region 41 and groove 42). The pattern may be formed by consecutively arranging pattern units in the circumferential direction.

[0085] As shown in FIGS. 4A to 4C, in one row of jig opening arrangement regions 17, vertically two sets of relatively convex regions 41 (22=4 in this example) and the grooves 42 arranged in the circumferential direction, are also referred to as a pattern unit. The interval (pitch) between the pattern units may be a distance between the centers (centers of gravity) of the jig openings 13 (becoming through holes) arranged in the circumferential direction.

[0086] There is no limit in the number of relatively convex regions 41 in the pattern unit. For example, grooves may be provided in the relatively convex regions 41 extending in the circumferential direction, and grooves may be provided in three sets in the vertical directiontwo sets in the circumferential direction, that is, as six relatively convex regions 41 in total.

[0087] The forms of the protrusions (relatively convex regions 41) and grooves 42 are not limited as long as they fit into the back surface of the mask 31. The back surface of the mask 31 herein refers to the surface that comes into contact with the jig opening arrangement region 17 when placing (embedding) the mask 31 in the jig opening arrangement region 17 formed on the outer side surface 16 of the drum-shaped jig 11. The surface of the mask 31 opposite to the back surface of the mask 31, that is, the surface that comes into contact with the workpiece 1, is also referred to as a front surface of the mask 31.

[0088] As shown in FIGS. 4A to 4C, in the second embodiment, the outermost surface of the selective plating mask member 50 that comes into contact with the surface of the workpiece 1 is composed of the surface of the mask 31 and the side edge portion 18 of the drum-shaped jig 11. The side edge portion 18 is a portion that is in contact with the jig opening arrangement region 17 and bottom portions 14 and 15 of the drum-shaped jig 11, and is a portion that is convex relative to the jig opening arrangement region 17. The workpiece 1 can be placed on the upper and lower side edge portions 18 of the drum-shaped jig 11 and the mask 31. It is preferable that the height of the side edge portion 18 and the surface of the mask 31, that is, the height of the area in contact with the workpiece 1, is the same.

[0089] In the third embodiment shown in FIG. 5, a side center portion 19 (which is the outer surface side 16) flush with (in same height with) the side edge portion 18 may be formed between the jig opening arrangement regions 17 placed in the vertical direction on the side surface of the drum-shaped jig 11. (Further, as shown in FIG. 4C, it does not have to be flush, and the side center portion 19 may be lower than the side edge portion 18.)

[0090] As shown in FIGS. 3A, 3B, and 4A to 4C, when the selective plating mask member 50 is produced by placing the mask 31 in the jig opening arrangement region 17 of the drum-shaped jig 11, the base portion 34 on the surface of the mask 31 (specifically, the outermost portion other than the edge 33) covers the drum-shaped jig 11 and therefore has a substantially cylindrical side surface shape. The edge 33 of the mask opening 32 is more raised (protruded) than the base portion 34 on the surface of the mask 31.

[0091] In the jig opening arrangement region 17 of the drum-shaped jig 11, for example, an opening (through-hole) other than the jig opening 13 (not shown) may be provided in a portion near the bottoms 14 and 15 of the drum-shaped jig 11. Protrusions (also referred to as legs of the mask 31) that are relatively long with respect to the thickness of the cylindrical member constituting the drum-shaped jig 11 are provided on the back surface of the mask 31, and these legs may be fitted into the openings. This configuration makes it difficult for the mask 31 to come off from the drum-shaped jig 11, resulting in a good fit between the two. Further, with this configuration, when fitting the two, the legs of the mask 31 are pulled from the inside of the drum-shaped jig 11, thereby making a fitting state of the two even better, and allowing an easy adjustment of the fitting state. There is no limit in the number of openings, and one mask unit (details will be described later) may have one or two or more openings.

[0092] There is no limit in the shape of the jig opening 13. The present embodiment shows a case in which the jig opening 13 is rectangular (square or rectangle) when viewed from the outside, but depending on a required shape of the selective plating area of an electronic member such as a terminal, the shape may be circular, oval, or other polygonal shape.

[0093] The size of the jig opening 13 is not limited as long as appropriate selective plating can be performed. An example of a specific size will be given in an example section below. It is preferable that the jig opening 13 corresponds to the shape and size of the selective plating area required for electronic components such as connectors and terminals.

[0094] The mask 31 according to the present embodiment embeds (covers) the jig opening arrangement region 17, which is a recess. The mask 31 according to the present embodiment has a mask opening 32 at a location corresponding to the jig opening 13. By fitting (placing) the mask 31 according to the present embodiment into the jig opening arrangement region 17, a through hole composed of the jig opening 13 and the mask opening 32 is provided. This through hole becomes a plating solution supply port.

[0095] In the present embodiment, the edge 33 of the mask opening 32 (more specifically, an entire edge 33, that is, the edge 33 surrounding the mask opening 32) is raised outward. By employing this configuration, leakage of the plating solution can be suppressed. The reason is as follows.

[0096] When the workpiece 1 is wrapped around the outer side surface 16 of the selective plating mask member 50 according to the present embodiment, the workpiece 1 is pressed against the surface of an uppermost mask 31 (and the side surface of the drum-shaped jig 11). Since the edge 33 of the mask opening 32 is raised, the workpiece 1 is pressed against the edge 33 of the mask opening 32, and since the edge 33 is deformed, it is possible to suppress the plating solution from entering between the mask 31 and the workpiece 1 at the outer circumference (edge 33) of the mask opening 32. Therefore, oozing of plating is also suppressed. Further, there is no need to waste plating solution, and economic loss is also suppressed.

[0097] With the above configuration, there is no limit in the material and aspect of the mask 31 according to the present embodiment. On the other hand, it is preferable that at least the edge 33 of the mask opening 32 of the mask 31 is made of rubber. When considering a processing effort, it is preferable that an entire mask 31 is made of rubber.

[0098] The rubber is not limited, but includes, for example, natural rubber, synthetic natural rubber, butadiene rubber, chloroprene rubber, silicone rubber (the present embodiment exemplifies these), acrylic rubber, urethane rubber, fluororubber, etc. Since the edge 33 of the mask opening 32 is made of rubber, when the workpiece 1 is pressed against the surface of the mask 31, the edge 33 deforms to be crushed according to the pressing force. As a result, the adhesion between the workpiece 1 and the edge 33 is improved, and leakage of the plating solution can be more effectively suppressed. It is preferable to use silicone rubber that has high chemical resistance to a chemical solution of the plating solution.

[0099] The dimension of the raised edge 33 of the mask opening 32 (protrusion distance and height from the base portion 34 other than the edge 33 when viewed from the outer side surface 16 to the inner side surface direction) may be appropriately set according to various conditions of plating. The conditions for this plating include the form of the jig opening arrangement region 17, the form of the jig opening 13, the planned thickness of the plating, the characteristics of the plating solution, the material of the entire mask 31 or the mask opening 32, etc.

[0100] A specific example of the height of the raised edge 33 of the mask opening 32 may be, for example, 0.1 mm or more and 0.5 mm or less, or 0.15 to 0.4 mm. The raised (protruded) height of the edge 33 of the mask opening 32 refers to the degree of protrusion (distance in the front view direction) of the mask opening 32 from the base portion 34 other than the edge 33 of the mask opening 32. With such a rubber edge 33 of the mask opening 32, when the raised height of the edge 33 of the mask opening 32 is 0.5 mm or less, the area of the through hole in front view is not reduced excessively if the edge 33 is crushed when the workpiece 1 is wrapped around the surface of the mask 31. So, a sufficient plating area can be secured. On the other hand, if the raised height is too small, there is a risk that the plating solution will infiltrate from between the mask 31 and the workpiece 1. Further, the width of the edge 33 of the opening 32 when viewed from the front is preferably 0.2 to 2.0 mm.

[0101] The distance between the mask opening 32 and the side edge portion 18 of the drum-shaped jig 11 according to the present embodiment is preferably 5.0 mm or more.

[0102] When viewed from the front, it is preferable that the mask 31 according to the present embodiment embeds (covers) the entire jig opening arrangement region 17, which is a recess, and the present embodiment shows such a case for example.

[0103] In the drum-shaped jig 11 of the third embodiment shown in FIG. 5, the thickness of the mask 31 (distance from the outer side 16 to the inner side of the side) may be set so that the portion other than the jig opening arrangement region 17 (side edge portion 18, side center portion 19) and the base portion 34 of the mask 31 are flush with each other, or the thickness of the mask 31 may be increased so that the entire mask 31 is raised (also called protruded) more than the side edge portions 18 and the side center portion 19.

[0104] Further, conversely, the portion of the mask 31 other than the edge 33 of the mask opening 32 may be lower than the side edge portion 18. Even in that case, when the edge 33 of the mask opening 32 is raised compared to the side edge portion 18 and the side center part 19, leakage of the plating solution can be suppressed, and oozing of plating can also be suppressed.

[0105] The mask 31 according to the present embodiment is preferably constituted by arranging a plurality of parts each having n (n is a natural number) mask units (for example, the area P between the broken lines in FIGS. 3A and 4A) corresponding to the pattern units of a predetermined pattern of the drum-shaped jig 11. One pattern unit of the drum-shaped jig 11 may be one mask unit. Further, for example, when the mask 31 covers a part of the jig opening 13 of the drum-shaped jig 11 as shown in FIGS. 4A and 4C, two (or more) pattern units of the drum-shaped jig 11 may be used as one mask unit.

[0106] Further, as shown in FIG. 5, in the selective plating mask member according to a third embodiment, the combination of the jig opening arrangement region 17 and the mask 31 may be arranged in a plurality of rows in the vertical direction.

[0107] The parts may be molded separately for each mask unit, or may be formed by integrally molding a plurality of mask units (n pieces).

[0108] Further, for example, in the third embodiment shown in FIG. 5, two masks 31 made up of long parts corresponding to the entire circumference of one row may be prepared, and the parts may be fitted to the outer side surface 16 of the drum-shaped jig 11 by arranging them one above the other. In this case, the mask unit that each part has is equal to the number of jig openings 13 arranged in the circumferential direction in one row of the jig opening arrangement regions 17. The mask 31 made up of a plurality of parts does not have to be a mask unit corresponding to a pattern unit, and the parts may have different sizes, and can be designed as appropriate.

[0109] In any case, when the mask 31 is made up of a plurality of parts, even if one part is damaged, only that part needs to be replaced, thus improving work efficiency.

[0110] The present embodiment shows a configuration in which when the mask 31 and the drum-shaped jig 11 are fitted together, the shape, size, and position of the mask opening 32 and the jig opening 13 are aligned. However, as long as the effects of the present invention are achieved, the mask opening 32 and the jig opening 13 may be misaligned when the mask 31 and the drum-shaped jig 11 are fitted together. Such a configuration includes a configuration in which the jig opening 13 and the mask opening 32 are misaligned, and a configuration in which the mask opening 32 is smaller than the jig opening 13.

[0111] In the case of the configuration in which the mask opening 32 is smaller than the jig opening 13, the lower side of the mask opening 32 may cover the lower contour of the jig opening 13.

[0112] There is no limit in the shape of the edge of the jig opening 13, and it is sufficient that the edge 33 of the mask opening 32 is raised when the mask 31 embeds the jig opening arrangement region 17. The shape of the edge of the jig opening 13 may be, for example, flat or recess, unlike the edge 33 of the mask opening 32.

[0113] Preferable examples of the size and positional relationship of the jig opening 13 of the drum-shaped jig 11 are as follows. As the following preferable example, the content described in Japanese Patent Application Laid-open No. 2018-165378 by the present applicant may be cited (particularly, the content related to FIGS. 3 to 5 of the publication in which the drum-shaped jig 11 of the present invention corresponds to the mask member 102 of the publication).

[0114] Similarly to the mask member 102 described in the publication, in the second embodiment shown in FIG. 4B, when the jig opening 13 is viewed from the inside of the drum-shaped jig 11 (when viewed from the back), it is preferable that the outer contour of the jig opening 13 (outside 13a of the jig opening 13) falls within the inner contour of the jig opening 13 (inside 13b of the jig opening 13). In this case, the angle of a gradient may be greater on the lower side than on the upper side.

[0115] The technical concept of the present invention is also reflected in the selective plating method in which the workpiece 1 is plated by supplying the plating solution to the jig opening 13 and the mask opening 32 in the workpiece 1 wrapped around a selective plating mask member. As a specific method for plating other than the selective plating mask member according to the present embodiment, a known method may be adopted.

[0116] The technical scope of the present invention is not limited to the above-described embodiments, but includes forms in which various modifications and improvements are made within the scope that can derive specific effects obtained by the constituent elements of the invention and their combinations.

EXAMPLES

[0117] The present invention will now be described in detail with reference to examples, but the present invention is not limited to the following examples.

Comparative Example 1, Example 1

(Selective Plating Mask Member and Drum-Shaped Jig)

[0118] In Example 1, the selective plating mask member was used, which had a configuration similar to that shown in FIGS. 4A to 4C, and had a plurality of through holes arranged in the circumferential direction in a staggered arrangement in two upper and lower rows. Each row has the same number of through holes. In Example 1, the two upper and lower rows of jig opening arrangement regions 17 are adjacent to each other, and the mask 31 is arranged (attached) in the jig opening arrangement regions 17.

[0119] In Comparative example 1, the jig opening arrangement region 17, which is a strip shaped recess provided along the circumferential direction on the outer side 16 of the drum-shaped jig 11, is not provided and the mask 31 is not provided either. That is, the drum-shaped jig 11 was used as a selective plating jig, in which the selective plating mask member of the present invention is not used, the jig opening 13 is provided on the side surface, but a strip shaped recess including the jig opening 13 is not provided.

Comparative Example 1

[0120] As a test material (material to be plated), a strip shaped workpiece 1 (width 50 mmthickness 0.2 mm) was used, which was a copper alloy sheet material NB109-EH (CuNiSnP based copper alloy) manufactured by Dowa Metaltech Co., Ltd. and was coated with Ni plating having a thickness of 1.2 m as an underplating.

[0121] The size of the opening (through hole) of the selective plating drum-shaped jig used in this comparative example, which is a rectangular through hole when viewed from the front, is 2.5 mm in the vertical direction1.5 mm in the circumferential direction (the same applies to the following examples).

[0122] For selective plating, a hard Au plating solution with an Au concentration of 20 g/L, a Co concentration of 0.3 g/L, and a pH of 4.15 was used, and by performing electroplating for 4 seconds under conditions of a liquid temperature of 55 C. and a current density of 27 A/dm.sup.2, a spot-shaped selective Au plating M with a target thickness of 0.4 m was formed on the surface of the strip shaped workpiece 1 facing the through hole.

Example 1

[0123] The selective plating mask member has two adjacent rows of jig opening arrangement regions 17 each having a width of 14 mm in the vertical direction, and the corresponding mask 31 is constituted by combining 15 pieces of parts. When each jig opening arrangement region 17 is embedded with each part (is placed), no gaps are formed between the ends of each part.

[0124] Each jig opening 13 of the drum-shaped jig 11 and each mask opening 32 are rectangular, each measuring 2.5 mm in the vertical direction and 1.5 mm in the circumferential direction, forming a through hole having the same size composed of the jig opening 13 and the mask opening 32, and a raised edge 33 was formed to have a height of 0.2 mm and a width of 0.5 mm around the entire circumference of each mask opening 32. Further, selective spot-shaped Au plating was performed to a target thickness of 0.4 m in the same manner as in Comparative example 1, except that a current density was set to 17 A/dm.sup.2.

[0125] FIG. 6 is a photograph showing an appearance of one selective Au plating on the workpiece 1 obtained in Comparative example 1.

[0126] FIG. 7 is a photograph showing an appearance of one selective Au plating on the workpiece 1 obtained in Example 1.

[0127] As can be seen from FIGS. 6 and 7, the oozing of plating was much less in Example 1 than in Comparative example 1.

[Plating Oozing Amount (Evaluation of Au Adhesion Amount)]

[0128] The Au spot plating (selective Au plating) formed on the surface of the workpiece 1 is dissolved in an Au stripping solution, and the Au in the stripping solution is quantitatively analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES), to thereby evaluate an Au adhesion amount.

[0129] The above through hole is a rectangle of 2.5 mm in the vertical direction and 1.5 mm in the circumferential direction, and Au (spot) plating is formed in an area (plating area) corresponding to the through hole. Then, it was found that the Au adhesion amount deposited per Au spot plating was 0.0397 mg in Comparative example 1 and 0.0279 mg in Example 1.

[0130] That is, even though the Au spot plating was applied with the same area and target thickness, the Au adhesion amount in Example 1 was reduced by about 30% compared to the Au adhesion amount in Comparative example 1.

[0131] This is because oozing of Au plating occurred (a thin Au plating film is formed outside the plating area corresponding to the through hole) in Comparative example 1, and unnecessary Au plating was adhered to the workpiece.

[0132] The plating thicknesses in Comparative example 1 and Example 1 were both approximately 0.4 m, which were equivalent each other. In Comparative example 1, there was a large loss in the Au adhesion amount due to oozing of selective Au plating, so it was necessary to increase the current density in order to achieve the same plating thickness for the same selective Au plating time.

Comparative Example 2

[0133] The same procedure was followed as in Comparative example 1 (including the Au plating time) except that the current density was set to 17 A/dm.sup.2, and spot-like selective Au plating was performed using the drum-shaped jig 11 (without the mask 31 attached).

[0134] As a result, similarly to the Comparative example 1, oozing of Au plating was observed in an area other than a designated spot area (selectively plated area). Further, due to the same current density and Au plating time, although the Au adhesion amount in Comparative example 2 was equivalent to that in Example 1, the thickness of the Au plating at the Au spot plating portion was only about 0.25 m due to the oozing.

Comparative Example 3

[0135] As shown in FIG. 5, in the selective plating mask member of Comparative example 3, two rows of jig opening arrangement regions 17 are formed on the side surface of the drum-shaped jig 11, and a side center portion 19 is provided flush with a side end portion 18 of the drum-shaped jig 11, and in each jig opening arrangement region 17, a plurality of through holes arranged in the circumferential direction are aligned in two rows, one above the other, with the number of through holes in each row being the same.

[0136] The selective plating mask member used herein was the mask member in which each jig opening 13 of the drum-shaped jig 11 and each mask opening 32 are rectangular, each measuring 2.5 mm in the vertical direction and 1.5 mm in the circumferential direction, forming the through hole having the same size composed of the jig opening 13 and the mask opening 32, but the edge 33 of the mask opening 32 is not raised.

[0137] A spot-like selective Au plating was formed on the surface of the strip shaped workpiece 1 in the portion facing the through hole, by performing electroplating in the same manner as in Comparative example 1, except that a hard Au plating solution with an Au concentration of 21 g/L and a Co concentration of 0.2 g/L was used for selective plating, and the liquid temperature was set to 55 C., pH was set to 4.15, the current density was set to 29 A/dm.sup.2, the target plating thickness was set to 1.15 m, and the Au plating time was set to 15 seconds.

[0138] In Comparative example 3, as in Comparative example 1, a large amount of oozing occurred in the plating of the workpiece 1.

Example 2

[0139] A spot-like selective Au plating was formed using the drum-shaped jig of Example 1 in the same manner as in Example 1, except that the current density was set to 30 A/dm.sup.2, the plating time was set to 11 seconds, and the target plating thickness was set to 1.3 m.

Comparative Example 4

[0140] A spot-like selective Au plating was formed using the drum-shaped jig of Comparative example 1 in the same manner as in Comparative example 1, except that the current density was set to 30 A/dm.sup.2 and the plating time was set to 11 seconds.

[0141] As a result, oozing of plating was less in Example 2 compared to Comparative example 4.

[0142] Further, due to the same current density and Au plating time, the Au adhesion amount in Comparative example 4 was equivalent to that in Example 2, but due to the oozing, the Au plating thickness of the Au spot-plated portion in Comparative example 4 was about 1.0 m, whereas that in Example 2 was about 1.3 m.

DESCRIPTION OF SIGNS AND NUMERALS

[0143] 1 . . . Workpiece [0144] 11 . . . Drum-type jig [0145] 12 . . . Locating pin (of workpiece) [0146] 13 . . . Jig opening [0147] 13a . . . Outside (of jig opening) [0148] 13b . . . Inside (of jig opening) [0149] 14 . . . Upper bottom portion [0150] 15 . . . Lower bottom portion [0151] 16 . . . Outer side surface [0152] 17 . . . Jig opening arrangement region [0153] 170 . . . Hole area [0154] 18 . . . Side edge portion [0155] 19 . . . Center side portion [0156] 21 . . . Belt mechanism [0157] 22 . . . Pressure belt [0158] 23 . . . Plating solution jet cell [0159] 24 . . . Plating solution ejection slit [0160] 31 . . . Mask [0161] 32 . . . Mask opening [0162] 33 . . . Edge [0163] 34 . . . Base portion [0164] 41 . . . Relatively convex region (within the jig opening arrangement region) [0165] 42 . . . Groove (within the jig opening arrangement region) [0166] 50 . . . Selective plating mask member [0167] 61 . . . Inlet side support roll [0168] 62 . . . Outlet side support roll [0169] P . . . Mask unit [0170] M . . . Selective Au plating