JP6909029B2 - Mask member for partial plating, partial plating equipment and partial plating method - Google Patents

Description

The present invention relates to a mask member for partial plating used when partially plating a strip-shaped metal material by an electroplating method, a partial plating apparatus using the mask member, and a partial plating method.

As a device for continuously partially plating a strip-shaped metal material such as a copper alloy, an iron alloy, or steel used for terminals and lead frames by an electroplating method, for example, Patent Document 1 and Patent. A partial plating apparatus using a cylindrical jig (drum jig) formed of a non-conductive material, which is disclosed in Document 2, is known. Here, the partial plating apparatus disclosed in Patent Document 1 is a horizontal type in which the plate surface of the metal material on the strip as the material to be treated is conveyed in a state of being substantially perpendicular to the direction in which gravity acts. The partial plating apparatus disclosed in Patent Document 2 is of a vertical type in which the plate surface of the material to be treated is conveyed in a state substantially parallel to the direction in which gravity acts.

In these partial plating devices, a material to be treated, which is a long metal band, is tightly wound around the outer peripheral surface of a drum jig that is rotatable in the circumferential direction but does not have a drive device. Partial plating is continuously performed by rotating the drum jig by the driving force for transporting the processing material.
Specifically, a plating solution jet portion and a jetting means are provided inside the drum jig, and a mask jig for partial plating having a plurality of openings is provided on the outer peripheral surface portion of the drum jig that comes into contact with the material to be treated. The plating solution is supplied to the surface of the material to be treated through the opening of the mask jig through the jetting portion of the plating solution, and the anode and cathode are arranged on the jetting portion of the plating solution or the inner peripheral surface side of the mask jig. By performing electrolysis by passing a current between the material to be treated and the material to be treated, partial plating corresponding to the shape of the opening of the mask jig is formed on the surface of the material to be treated. When the formed partial plating is spot-shaped, the partial plating may be referred to as spot plating.
In these partial plating devices, as a method of performing partial plating in synchronization with the strip-shaped material to be processed and the drum-shaped jig, for example, a plurality of positioning pins are provided on the outer peripheral portion of the mask member used for partial plating. By providing a plurality of positioning holes on the outer peripheral portion of the material to be processed and fitting the plurality of positioning pins with the plurality of holes, the driving force for transporting the material to be processed is transmitted to the drum-shaped jig. Many methods have been put into practical use, such as a method of synchronizing the conveying speed of the material to be processed and the outer peripheral speed of the drum jig.

Japanese Unexamined Patent Publication No. 2006-283127 Japanese Unexamined Patent Publication No. 2013-100593

Since the partial plating apparatus disclosed in Patent Document 1 and Patent Document 2 unwinds and winds a long material to be processed by a reel-to-reel method, partial plating can be continuously performed. The productivity is higher than that of the partial electroplating apparatus of the type, but from the viewpoint of economy, even higher productivity is required.
Therefore, in order to improve the productivity of the continuous partial plating apparatus, after performing partial plating in a plurality of rows in the plate width direction of the material to be processed, the material to be partially plated is subjected to means such as a slitter. A method of dividing into a plurality of metal strips along the longitudinal direction has been proposed.

FIG. 1 illustrates a cross-sectional view of a mask member for partial plating having two rows of openings at the top and bottom, which is used in a vertical type partial plating apparatus conventionally used. Here, the mask member 102 is provided with two upper and lower openings 102c in the vertical direction, and the plating solution is supplied to the surface of the material 10 to be treated through these openings, and the anode 104 and the cathode provide the plating solution. Partial plating is performed by passing an electric current between a certain material 10 to be treated.
However, in a vertical type partial plating apparatus, when partial plating is performed using a mask member for partial plating in which a plurality of rows of openings are arranged at the top and bottom as shown in FIG. 1, the lower openings (two rows from the top). It was found that in the partial plating obtained corresponding to (after the eyes), the plating may be discolored or the film thickness distribution of the plating layer may deteriorate in the partially plated spot depending on the electrolytic conditions of electroplating. did.

Therefore, in view of such conventional problems, the present invention uses a vertical partial plating apparatus to continuously perform partial plating in a plurality of rows in the width direction of a strip-shaped metal material. It is an object of the present invention to provide a mask member for partial plating, a partial plating apparatus, and a partial plating method using the same, which can prevent discoloration and obtain a good plating film thickness distribution within a spot of partial plating.

As a result of diligent research to solve the above problems, the present inventors have provided a plurality of rows of openings in the vertical direction of the mask member, and spraying and supplying the plating solution from the lateral direction to each opening is the best. When the plating solution ejected into the openings of the row falls due to the action of gravity, it interferes with the jet flow of the plating solution ejected into the openings in the second and subsequent rows from the top, so the metal material exposed in the openings. It was found that the plating solution stayed near the surface of the plating solution and the metal ions were not sufficiently supplied. Therefore, by forming the openings in the second and subsequent rows from the top so that the plating solution does not stay, it is possible to prevent discoloration of partial plating and obtain a good plating film thickness distribution in the spot of partial plating. We have found what we can do and have completed the present invention.

That is, in the present invention, it is a substantially cylindrical mask member for partial plating used in a vertical partial plating apparatus that continuously performs partial plating on a strip-shaped metal material, and is in the circumferential direction of the mask member. A plurality of rows of openings formed apart from each other are formed in the width direction of the mask member, and the plating solution of the openings formed in rows below the second row from the top is used. Provided is a mask member for partial plating in which the thickness of the periphery of at least the lower end portion on the supply side is thinner than the thickness of the peripheral portion of the opening.
Further, the peripheral portion of the opening at least at the lower end on the side where the plating solution of the opening is supplied has a gradient, or the thickness around the lower end is thinner than the thickness of the peripheral portion of the opening. Further, a gradient may be provided on the outer peripheral portion thereof.
These partial plating mask members can be provided with a recess that serves as a passage path for the strip-shaped metal material on the side in contact with the strip-shaped metal material, and a recess for positioning can be provided at the peripheral edge of the recess. A plurality of pins may be formed so as to project.

Further, in the present invention, the partial plating mask member is provided on the outer peripheral surface portion, and has a cylindrical drum jig in which a strip-shaped metal material is conveyed along the outer peripheral surface portion. A partial plating apparatus that energizes the strip-shaped metal material while supplying a plating solution through the opening of the member to continuously electroplate a part of the metal material on the strip, and the above-mentioned Using a partial plating device, energization is performed while supplying a plating solution to the strip-shaped metal material through the opening of the partial plating mask member, and electricity is continuously applied to a part of the surface of the strip-shaped metal material. A partial plating method for plating is provided.

According to the present invention, when a plurality of rows of partial plating is performed in the width direction of a strip-shaped metal material using a vertical partial plating apparatus, discoloration of the plating is prevented and a good film thickness of the plating layer is obtained. It becomes possible to obtain a distribution and productivity is improved.

It is sectional drawing of an example of the conventional mask member for partial plating used in a vertical type partial plating apparatus. It is sectional drawing in the horizontal direction of the partial plating apparatus of this invention. It is sectional drawing of one Embodiment of the reference example of the mask member for partial plating of this invention. It is sectional drawing around the opening of the reference example of the mask member for partial plating of this invention. It is sectional drawing around the opening of the reference example of the mask member for partial plating of this invention. It is sectional drawing of the vicinity of the opening of the Example of the mask member for partial plating of this invention. It is sectional drawing around the opening of the comparative example of the mask member for partial plating of this invention. It is a figure which shows the distribution of the Au plating film thickness in the partial plating spot obtained in the comparative example of this invention. It is a figure which shows the distribution of the Au plating film thickness in the partial plating spot obtained in Example 1 of this invention.

Hereinafter, the mask member for partial plating according to the present invention, the partial plating apparatus, and the partial plating method using the same will be described in detail with reference to the accompanying drawings.

In the partial plating method of the present invention, a copper alloy plate, an iron alloy plate such as ordinary steel, special steel, or stainless steel can be used as the strip-shaped metal material of the material to be treated. The thickness of the strip may be appropriately selected depending on the intended use, but usually, a strip having a thickness of about 0.1 to 0.8 mm is used. The metal used for partial plating is usually an expensive precious metal such as gold or silver, but prior to the partial plating, a strip-shaped metal material may be base-plated with a metal such as nickel. In the above-mentioned base plating, the base plating and the partial plating can be continuously performed by connecting the reel-to-reel type base plating equipment to the partial plating apparatus of the present invention.

FIG. 2 shows a cross-sectional view of a part of the partial plating apparatus of the present invention cut in a horizontal plane. The strip-shaped metal material 10 unwound from the unwinding device (not shown) is conveyed in the direction indicated by the arrow A by the tension applied by the unwinding device (not shown), and then traveled by the inlet side support roll 108. Is converted, and is wound in close contact with the outer peripheral surface of the partial plating mask member 102 that also serves as the outer peripheral surface portion of the cylindrical drum jig 100, and is wound again by changing the direction with the outlet side support roll 110. In this case, a minute backward tension may be applied to the strip-shaped metal material 10 in order to ensure the close contact between the strip-shaped metal material 10 and the partial plating mask member 102. The mask member 102 for partial plating in close contact with the strip-shaped metal material 10 synchronizes with the peripheral speed of the strip-shaped metal material 10 by using means such as fitting described later, and is centered on a central axis (not shown). Rotates in the direction indicated by the arrow B. The mask member 102 for partial plating is made of a non-conductive material such as polyvinyl chloride (PVC) resin, has a predetermined interval in the circumferential direction, and is used for partial plating in a plurality of rows in the vertical (vertical) direction. The opening 102c is provided. The openings 102c for partial plating in a plurality of rows may be provided on the same straight line in the vertical direction or may be provided in a staggered manner.

Inside the cylindrical drum jig 100, a plating solution jet portion 106 and an anode 104 are provided so as to face a part of the inner peripheral surface portion of the partial plating mask member 102. The plating solution jet portion 106 is formed of a non-conductive material such as polyvinyl chloride (PVC) resin, and has a shape in which a part of the cylinder is cut out so that its horizontal cross section is substantially fan-shaped. A plurality of slits 106a penetrating from the inner peripheral surface to the outer peripheral surface of the plating solution jetting portion 106 are provided at a height facing a plurality of rows of openings 102c for partial plating provided in the plating mask member 102, and an anode is provided. The 104 is arranged in the slit 106a.

In the partial plating method of the present invention, a plating solution is supplied from the inner peripheral surface side of the plating solution jetting portion 106 through a plurality of slits 106a on the outer peripheral surface side by a plating solution supply device such as a pump (not shown), and the above-mentioned plurality of rows The plating solution is sprayed onto the surface of the strip-shaped metal material 10 which is a material to be treated exposed in a spot shape in each opening 102c for partial plating, and the strip-shaped metal material 10 is used as a cathode, which is shown in the figure. A power supply device such as a rectifier is used to pass a current between the anode and 104 to perform electrolysis, thereby partially plating the surface of the strip-shaped metal material 10 which is a material to be treated that is exposed in a spot shape. The plating solution ejected into the opening 102c is recovered in a plating solution tank (not shown) provided at the bottom of the cylindrical drum jig 100, but the recovered plating solution is circulated using a plating solution recovery device such as a pump (not shown). However, it may be used again for partial plating.

The mask member 102 for partial plating is formed of a material having a certain thickness of, for example, about 10 mm in order to secure mechanical strength. However, when a hole is made in the material and the opening 102c is directly formed, the opening is formed. If the area of 102c is small, it is about 1 × 1 mm. Therefore, even if the plating solution is supplied to the opening 102c by the plating solution jet portion, the supply amount of the plating solution (metal ion) may be insufficient. Therefore, normally, a non-penetrating recess having an area several times to a dozen times the area of the opening 102c (hereinafter referred to as an opening peripheral portion) is provided at a place where the opening 102c of the partial plating mask member 102 is provided. ) Is provided, and the opening 102c is provided at the center of the peripheral portion of the opening. The thickness of the peripheral portion of the opening of the partial plating mask member corresponding to the bottom of the recess is usually about 1 to 3 mm.

FIG. 3 shows a cross-sectional view of an embodiment of a reference example of the mask member for partial plating of the present invention. It should be noted that this cross-sectional view is a cross-sectional view showing the partial plating apparatus of FIG. 2 cut along the IV-IV line, and is an example in which two rows of openings 102c for partial plating are formed in the vertical direction (upper and lower), and they face each other. The cross section of the plating solution jet portion 106 to be used is also shown. The cross-sectional view of the partial plating mask member shown in FIG. 3 is drawn as a peripheral portion of the opening in order to avoid complication.
The arrangement of the mask member 102 for partial plating, the jetting portion 106 of the plating solution, and the anode 104 in the partial plating apparatus of the present invention is basically the same as that of the conventionally used partial plating apparatus shown in FIG. The thickness around at least the lower end of the partial plating opening 102c arranged on the lower side of the plating mask member 102 on the side to which the plating solution is supplied is made thinner than the other parts around the opening. Is a feature.

As shown in FIG. 3, in the reference example of the mask member for partial plating of the present invention, a recess that serves as a plate passage path for the strip-shaped metal material 10 on the side in contact with the strip-shaped metal material 10. 102a can be provided. Further, a positioning pin 102b can be formed so as to project from the peripheral edge of the recess 102a. The positioning pin 102b is fitted with the positioning holes provided at both ends of the metal material 10 (not shown) to synchronize the peripheral speeds of the partial plating mask member 102 and the strip-shaped metal material 10. Can be used for.

FIG. 4 shows an enlarged view of the vicinity of the opening 102c for partial plating arranged on the lower side (second row from the upper side) shown in FIG. In this embodiment, the thickness of the periphery of the lower end portion of the opening 102c on the side where the plating solution is supplied is made thinner than the thickness of the other portion of the opening peripheral portion. Such processing can be performed by so-called counterbore processing. By performing such processing, the plating solution supplied to the opening 102c from the right direction of FIG. 4 can be easily discharged downward, and the plating solution does not stay in the opening 102c. It is possible to prevent the plating from being burnt inside and to obtain a good plating film thickness distribution. The thickness d of the portion left as the opening 102c for determining the shape of the spot for partial plating is not particularly limited, but the mask member 102 for partial plating is caused by wear due to the strip-shaped metal material 10 or jetting of plating liquid. Since it is subject to wear, it is preferable to have a thickness of 0.5 mm or more in consideration of the service life. Further, the length of the region l to be processed thinner than the other portions around the opening is preferably 0.5 mm or more. In FIG. 4, only the lower end portion of the opening 102c is thinner than the thickness of the other portion around the opening, but the same processing is performed on the entire opening 102c of the substantially cylindrical partial plating mask member. It may be applied to the circumference. Further, in the present invention, the shape of the openings 102c for partial plating arranged on the upper side is not particularly specified, but the shape shown in FIG. 4 may be used.

FIG. 5 shows a cross-sectional view of another embodiment regarding the shape around the opening of the reference example of the mask member for partial plating of the present invention. In the present embodiment, a gradient is formed by leaving a part of the opening 102c. Such processing can be performed by chamfering. The thickness of the portion where the initial opening 102c is left is 40 to 60% of the thickness of the other portion of the peripheral portion of the opening for the same reason as described above, and has a thickness of 0.5 mm or more. preferable. The angle of the gradient can be 30 to 90 ° with respect to the wall surface of the opening 102c.
Figure 6 shows a cross-sectional view of implementation form about the shape of the peripheral openings of the partial plating mask member of the present invention. This embodiment is a combination of the embodiment of the reference example shown in FIG. 4 and the embodiment of the reference example shown in FIG.
In the embodiment of FIGS. 5 and 6, only the lower end portion of the opening 102c is processed, but the same processing may be applied to the entire circumference of the opening 102c. Further, in the present invention, the shape of the openings 102c for partial plating arranged on the upper side is not particularly specified, but the shapes shown in FIGS. 5 and 6 may be used.

[Measurement method of plating film thickness distribution in partial plating]
Using a fluorescent X-ray film thickness meter SFT-110A manufactured by Hitachi High-Tech Science Co., Ltd., the plating film thickness on the vertical center line of the partial plating spot was measured at 0.2 mm intervals, and the plating film thickness in the partial plating spot was measured. The distribution was measured. The collimator diameter used was 0.2 mmφ, and the measurement time was 10 s per point.

[Comparison example]
As a test material, a strip-shaped copper alloy plate material NB109-EH material (Cu-Ni-Sn-P-based copper alloy) manufactured by DOWA Metal Tech Co., Ltd. is coated with 1.2 μm-thick Ni plating as a base plating. A plate material (width 54.0 mm × thickness 0.2 mm) was used.
FIG. 7 shows a cross-sectional view of the partial plating mask member 102 used in this comparative example in the vicinity of the opening 102c. The thickness of the peripheral portion of the opening is 1.2 mm. The size of the opening 102c is 2.0 mm in the width direction × 1.2 mm in the circumferential direction (the same applies to the following examples).
For partial plating, a hard Au plating solution with Au concentration: 10 g / L and Co concentration: 0.2 g / L was used, liquid temperature: 55 ° C., pH: 4.25 current density 30 A / dm ² , target plating film thickness. By electroplating at 0.5 μm, spot-shaped partial Au plating was formed on the surface of the strip-shaped metal material 10 at the portion facing the opening 102c.
FIG. 8 shows the plating film thickness distribution in the width direction in the spot of the lower row (second row from the top) partial Au plating obtained in this comparative example. In the case of this comparative example, the Au plating film thickness of the Au partial plating spot corresponding to the opening 102c in the upper row was 0.49 ± 0.04 μm, but the Au plating film thickness corresponding to that in the lower row was 0. It was 44 ± 0.11 μm (± 25.0% with respect to the film thickness), and the film thickness distribution deteriorated and a decrease in the plating film thickness due to the occurrence of discoloration was observed.

[ Reference example 1]
As the mask member 102 for partial plating, a mask member 102 having a cross-sectional shape near the opening 102c shown in FIG. 4 was used, and the opening 102c was subjected to the same conditions as in Comparative Example 1 except that electroplating was performed with a target plating film thickness of 0.8 μm. Spot-shaped partial Au plating was formed on the surface of the strip-shaped metal material 10 at the portion facing the surface. Here, the thickness d of the opening 102c is 0.7 mm, and the length of the region l to be processed thinner than the other portions around the opening is 1 mm.
The Au plating film thickness of the Au partial plating spot obtained in this example was 0.85 ± 0.05 μm in the upper row and 0.80 ± 0.15 μm in the lower row (± 18.8 with respect to the film thickness). %), And the film thickness distribution of the partial Au plating in the lower row was improved as compared with the above-mentioned comparative example, the range of burn occurrence was reduced, and the degree of burn was reduced.

[ Reference example 2]
As the mask member 102 for partial plating, a strip-shaped portion facing the opening 102c under the same conditions as in Comparative Example 1 except that electroplating was performed using a mask member 102 having a cross-sectional shape near the opening 102c shown in FIG. A spot-shaped partial Au plating was formed on the surface of the metal material 10. Here, the thickness d of the opening 102c is 0.7 mm, and the angle of the gradient is 45 °.
The Au plating film thickness of the Au partial plating spot obtained in this example was 0.55 ± 0.02 μm in the upper row and 0.45 ± 0.07 μm in the lower row (± 15.6 with respect to the film thickness). %), And the film thickness distribution of the partial Au plating in the lower row was improved as compared with the above-mentioned comparative example, the range of burn occurrence was reduced, and the degree of burn was reduced.

[Example 1 ]
As the mask member 102 for partial plating, a strip-shaped portion facing the opening 102c under the same conditions as in Comparative Example 1 except that electroplating was performed using a mask member 102 having a cross-sectional shape near the opening 102c shown in FIG. A spot-shaped partial Au plating was formed on the surface of the metal material 10. Here, the thickness d of the opening 102c is 0.7 mm, the length of the region l is 1 mm, and the gradient angle is 45 °.
Figure 9 shows a plating film thickness distribution in the width direction of the obtained (second row from the top) column below the spot of partial Au plating in this example. In the case of this comparative example, the Au plating film thickness of the Au partial plating spot corresponding to the opening 102c in the upper row is 0.50 ± 0.02 μm, and that in the lower row is 0.47 ± 0.04 μm (to the film thickness). On the other hand, it was ± 12.0%), and a good film thickness distribution was obtained even in the lower row, and plating discoloration did not occur.

As described above, when partial plating is performed using the mask member for partial plating of the present invention, no discoloration occurs in the plating, and a good plating film thickness distribution can be obtained even in the lower opening.

100 Drum-shaped jig 102 Mask member 102a Recess (passing part of metal plate material)
102b Positioning pin 102c Opening 104 Anode 106 Plating liquid jet 106a Slit 108 Inlet side support roll 110 Outlet side support roll

Claims (6)

A substantially cylindrical mask member for partial plating used in a vertical partial plating apparatus for continuously partial plating on a strip-shaped metal material, which is formed so as to be separated from each other in the circumferential direction of the mask member. A plurality of rows consisting of the plurality of openings are formed in the width direction of the mask member, the thickness of the peripheral portion of the openings of the mask member is 1 to 3 mm, and the rows below the second row from the top. a 40% to 60% the thickness d of the periphery of at least the lower end portion of the formed side to be supplied to the plating liquid in the opening of the thickness of the opening peripheral portion, further the slope provided on the outer periphery thereof Also, a mask member for partial plating. The mask member for partial plating according to claim 1, wherein the thickness d around the lower end portion is 0.5 mm or more. The mask member for partial plating according to claim 1, wherein a recess serving as a passage path for the strip-shaped metal material is provided on the side in contact with the strip-shaped metal material. The mask member for partial plating according to claim 3 , wherein a plurality of positioning pins are formed so as to project from the peripheral edge of a concave portion that serves as a passage path for a strip-shaped metal material. The mask member for partial plating according to any one of claims 1 to 4 is provided on the outer peripheral surface portion, and has a cylindrical drum jig in which a strip-shaped metal material is conveyed along the outer peripheral surface portion. Partial plating in which a plating solution is supplied to the strip-shaped metal material through an opening of the partial plating mask member to energize the strip- shaped metal material, and a part of the strip-shaped metal material is continuously electroplated. Device. Using the partial plating apparatus according to claim 5 , energization is performed while supplying a plating solution to the strip-shaped metal material through the opening of the partial plating mask member to apply electricity to a part of the strip-shaped metal material. A partial plating method that continuously electroplats.

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