JPS62274092A - Method and device for plating strips - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention "Industrial Application Field The present invention relates to an improved plating method and apparatus useful for plating various metal strips, especially stripe plating. It is.

[Prior art and problems] In recent years, lead frame materials for transistors and ICs, for example, have been made of ordinary metals or alloys as base materials, and only for contacts and other parts where high quality materials are required. By plating gold, silver, and other precious metals in stripes (or spots), we can minimize the use of these expensive precious metals, reduce costs as much as possible, and maintain high performance. Measures are being taken.

This will be explained using stripe plating as an example.

Conventionally, two methods have been used to perform stripe plating using electrochemical plating.

The method is to leave only the striped plated surface of the strip metal strip, mask all other surfaces, and then immerse the entire surface of the masked strip in a plating solution to apply stripe plating to the unmasked areas. This is the full-surface immersion method, in which the strip is run horizontally (in some cases vertically), the necessary masking is applied to only one side of the strip, and the plating solution is applied to the masked side of the strip from a nozzle. This is a jet method in which the metal is sprayed and only one side is plated.

However, with the above-mentioned full-surface immersion method, it is inevitable that the entire surface to be plated is masked, so the masking tape used must be hung up a lot, and it is expensive, so it has become a method that is difficult to adapt to in today's era of intense market competition. be.

On the other hand, the jet method has the advantage that masking tape only needs to be used on one side because the plating solution is sprayed on one side only, but since the plating solution is sprayed by a jet, uneven stirring of the plating solution is avoided. Therefore, uneven plating tends to be a problem.

In recent years, development competition in the field of electronic products has become increasingly intense, and while demands for lower product costs have become more stringent, there has also been a growing trend towards products that are inexpensive and of superior quality. For this reason, in the case of stripe plating, in the past, there were many examples of one stripe per strip, but recently J-3 has been applied to lead frames for mini transistors, etc. Recently, there has been a demand for a product in which several stripes each having a width of 1#1111 are formed on a single strip at various intervals.

When plating a large number of stripes on one strip in this way, if the jet method is used, there will naturally be a difference in agitation of the plating solution between the center and the ends of the strip. This makes it very difficult to plate all stripes uniformly, and masking it also requires time and expense. There were high hopes for his appearance.

[Object of the Invention] The present invention was made in view of the above-mentioned circumstances, and it is possible to uniformly stir the plating solution over the entire area and also to enable high-speed stirring. The object of the present invention is to provide a method for plating a band-shaped body and a plating apparatus for the same, which can plate both uniformly and at high speed, and which can keep the masking process to a minimum.

[Summary of the Invention] In other words, the gist of the present invention is to provide a plating method in which, when plating a strip, the strip is moved in the longitudinal direction and a plating solution is ejected and flowed along the direction of movement, and a plating method such as that. A conveyance device that moves a strip to be plated to enable plating, and a conveyance device that works together with the conveyance device to sandwich the material to be plated and spray a plating liquid onto the clamping surface in the direction of movement of the material to be plated. The plating equipment has a plating bath configured to move freely, thereby uniformizing the agitation of the plating solution on the plated surface of the strip and minimizing the cathode thin layer, resulting in high-quality plating. This can be realized at high speed, and the use of masking tape can be kept to the minimum necessary.

[Example] The following is a sequential explanation based on examples.

FIG. 1 is an explanatory diagram showing an embodiment of a plating apparatus according to the present invention, and FIG. 2 is a sectional view taken along the line AA' in FIG.

In the figure, 3 is a strip to be plated, and there are pre-treatment steps and post-treatment steps before and after it, but illustration thereof is omitted. Also,
Although there is a winding device for winding up the strip in the direction of the arrow in FIG. 1, this is also omitted.

A conveying device 1 consisting of an endless belt capable of moving the strip 3 in the direction of the arrow in synchronization with the winding device is disposed on the strip 3, and a guide roll 2 is rotated in the direction of the arrow. This causes the endless belt to rotate in the direction of the arrow.
The belt-shaped body 3 is configured to be transported in the direction of the arrow in FIG.

On the other hand, a plating tank 6 is disposed with a packing 7 interposed therebetween at a position facing the conveying device 1 and holding the strip 3 together with the conveying device 1.

However, the side of the plated strip 3 side of the plating tank 6 as a lever is formed as an open opening, and when the plating tank 6 is filled with the plating solution 11, the plating solution 11 is applied to the plated surface of the strip.
It is configured to be in contact with 0.10. The plated surface 10.10 of this embodiment is the so-called striped plated surface described above, and as can be seen from the cross-sectional view in FIG. 2, masking tape 12.12 is pasted on the non-plated surface. The sections of the striped surface 10 are regulated.

In the figure, 8 is an anode plate for stripe plating. Now, the case of plating using the plating apparatus according to the present invention configured as described above will be described below.

The strip 3 to be plated is moved in the direction of the arrow in FIG. 1, and in response, the plating solution circulation pump 9 operates, and the plating solution is pushed out from the pump 9 in the direction of the arrow in FIG. 1, supplying the plating solution. On the other hand, there is a suction nozzle 5 on the opposite side of the spout nozzle 4 that collects the plating solution 11. It is configured to be collected by suction. The plating solution thus sucked and collected is cleaned by a plating solution cleaning device, although not particularly shown in these figures, and is circulated to the pump 9 as a fresh plating solution.

Since the plating apparatus according to the present invention has the above-described configuration, the plating solution 11 in the plating tank 6 always flows in the same direction following the moving direction of the plated surface 10. Fresh, cleaned plating solution is always forcibly injected from the side, and tired plating solution is removed by suction from the end.

In this embodiment, one injection nozzle or one suction nozzle is provided, but if the width of the strip to be plated, that is, the width of the area to be plated becomes wider, multiple nozzles of each nozzle may be installed. It would be easy to make it into a book. In this way, it is easy to adjust the flow or agitation of the plating solution 11 in the plating bath 6 to the same conditions for the plating surface of the material to be plated, thereby making the plating conditions of the strip to be plated uniform. For example, it is possible to make the plating layer of each stripe of a lead frame having a plurality of stripes plating uniform.

Moreover, as mentioned above, clean plating solution flows into the plating tank 6 from one direction and is suctioned away from the other side, so that the gas (hydrogen ions) generated during plating can be quickly suctioned and removed. This method minimizes the formation of cathode diffusion layers and enables high-speed plating with high efficiency.

On the other hand, from the perspective of masking non-plated parts,
The area in which the material to be plated comes into contact with the plating solution is limited to the open part of the plating tank, which is incomparable to the above-mentioned full-surface immersion method; Compared to the case where masking is required, in the case of the present invention, only masking is required within the range limited by the packing 7, which has the advantage of saving a large amount of masking tape, which is a consumable item. The cost reduction effect brought about by savings is greater than expected.

In addition, although the above-mentioned embodiment illustrated the case where the material to be plated 3 is moved horizontally, there is no need to limit it to such horizontal movement, and there is no problem even if it is configured to move vertically in the up and down direction.

FIG. 3 shows another embodiment of the plating apparatus according to the present invention, and FIG. 4 shows a sectional view taken along line B-8' in FIG. 3, and is similar to FIGS. The same reference numerals indicate the same configurations.

The most distinctive feature of this embodiment is that the plating tank 61
The belt is constructed in the shape of an endless belt with an outward opening and a cross section consisting of a square-shaped groove, and can be rotated synchronously with the endless belt 1 of the conveying device 1 by means of a blade roll 2'. If such a plating tank 61 is made of, for example, rubber, it also has the secondary effect that the packing 7 in the embodiments shown in FIGS. 1 and 2 can be omitted. In addition, 13 in FIG. 4 is an anode, and it is also possible to configure it so that it is electrically connected to the guide roll 2'.

Above, the present invention has been specifically explained based on two embodiments, but it goes without saying that these are meant as specific examples and do not mean any limitations on the structure. Of course, various design changes are possible within the scope of the technical idea of the present invention.

"Effects of the Invention" As described above, according to the plating method and apparatus according to the present invention, it is possible to make the flow stirring direction of the plating solution uniform and constant for all plating surfaces.
It is possible to maintain each plating layer to be of uniform, stable, and high quality at all times, and not only can we provide products that fully meet the demand for high precision and high quality from customers, but also masking, which is a consumable item. In response to the bottleneck of reducing the cost of tape, we have significantly reduced the amount of masking tape used.
It is of great significance that this breakthrough has been made, and the effectiveness of the present invention, which can solve the two problems of reducing product costs and improving product quality at once, must be highly praised.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing one embodiment of the plating apparatus according to the present invention, FIG. 2 is a cross-sectional view taken along line AA' in FIG. 1, and FIG. 3 is an explanatory diagram showing another embodiment of the plating apparatus according to the present invention. The explanatory diagram shown in FIG. 4 is a sectional view taken along line BB' in FIG. 3. DESCRIPTION OF SYMBOLS 1... Conveyance device, 3... Plated object (band-shaped body), 4... Spray nozzle, 5... Suction nozzle, 6.61... Plating tank, 8.13... Anode, 10... Surface to be plated, 11... Plating solution, 12... Masking tape. Agent Patent Attorney Sato Fujio tEJ 73 Country f 4 Country

Claims (6)

[Claims] (1) A method of plating a strip by moving the strip to be plated in the longitudinal direction and plating the plating solution while applying a flow velocity in the same direction as the moving direction of the material to be plated. (2) A conveyance device that faces the open side of the plating tank where the plating solution in the plating tank comes into contact with the material to be plated, and moves the material to be plated to a position where the material to be plated is held in cooperation with the plating tank. A plating apparatus comprising: a spout nozzle for spouting a plating solution in the traveling direction of the plated material on one side of the plating tank, and a suction nozzle for sucking the plating solution on the other side. (3) The plating tank itself is open on the side where the plating solution contacts the material to be plated, and its cross section is approximately U-shaped, forming an endless belt that can rotate along with the material to be plated. On one side of the U-shaped groove of the U-shaped endless belt, there is a jetting nozzle that spouts the plating solution in the moving direction of the material to be plated, and on the other side, the plating solution is sucked from inside the groove. A plating apparatus is provided with a suction nozzle that moves the material to be plated to a position where the material to be plated is sandwiched between the two nozzles. (4) The plating apparatus according to claim 2 or 3, wherein the conveying device for moving the material to be plated is an endless belt. (5) The plating apparatus according to any one of claims 2 to 4, wherein the direction in which the material to be plated is moved is a vertical up-down direction. (6) The plating apparatus according to any one of claims 2 to 4, wherein the direction in which the material to be plated is moved is a horizontal direction.