JPS6116427B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a partial plating method.

The present invention relates to a method for improving the stability of plating, improving the stability of plating, and increasing the speed of plating in a method of partially plating using a plurality of pipes. IC (integrated circuit) frame,
Other electrical contact members are plated with precious metals to ensure electrical conductivity and long-term reliability. The conventional partial plating method requires a special mask, complicated jigs and processes such as resist coating and printing, and tape attachment, making it impossible to easily perform partial plating. A conventional example will be explained based on an actual rotating example shown in the drawings. 1st
As shown in the cross-sections shown in Figures A, B, and C, A is equipped with an elastic body 2 on one side of the material 1 to be plated, which serves as a cathode, and has a through hole in the part that requires plating liquid, and the other side is an elastic body sheet. 3 completely covers the material to be plated 1 and presses it from above the elastic sheet 3 via the air cylinder 4. Then, plating liquid is applied from the nozzle 5, which also serves as an anode, located below the elastic body 2. Back side 6 of material to be plated 1
At the same time, plating is performed on the back surface 6 at the same location, and the unnecessary plating liquid is collected from the hole 7. B: The material 10 to be plated with the resist 9 applied to other parts except for the part 8 that requires plating is immersed in a plating solution, and the material 10 to be plated is used as a cathode and the plating solution is used as an anode to perform plating. After plating the portion 8 to be
This is done by removing . C, a cathode is attached to the material 13 to be plated with insulating tape 12 pasted on the other parts except for the part 11 that requires plating, and
Part 1 that requires plating using the plating liquid as an anode
This can be done by removing the insulating tape 12 after plating. Among these partial plating methods, the method shown in Figure 1A requires a special mask for each item to be plated, and
Mask production costs are high and the production period is long.

Partial plating on bent parts, cut-and-raised parts, etc. is not possible.

Even a simple mask change, that is, a change of processed products, requires 3 ^to 8 ^hours , making it unsuitable for many types of processing.

Mechanical equipment becomes large, occupies a large space, and is expensive, so it takes a long time to depreciate.

Expensive plating solution is wasted because the plating solution is transferred to the next step with the plating solution attached to most parts of the material to be plated due to leakage of the plating solution from the mask gap and capillary action between the mask and the material to be plated.

In addition to the following problems, the plating method shown in (b) requires two to three steps to apply or print the resist onto the material to be plated, which increases the number of man-hours.

It cannot be applied to parts that have undergone processing such as bent parts or cut-and-raised parts.

It is difficult to reliably maintain adhesion between the resist and the material to be plated, and areas that do not require plating are often plated.

In order to completely divide the resist, 2~
Three steps are required, which increases the number of man-hours.

In addition to these problems, the plating method shown in C requires very complicated work such as pre-processing the insulating tape and pasting the insulating tape several times in order to spot-plate. There is a lack of certainty in the ratio of

Plating small parts is technically difficult.

It is difficult to apply this method to materials to be plated that have bent parts or cut and raised parts.

Although the currently used partial plating method has many problems due to problems such as these, it was used out of necessity because there was no other suitable solution.

The present invention solves all of these problems,
The present invention also provides a method for easily partially plating a material to be plated which has been subjected to bending, cutting and raising, drawing, etc. The present invention will be explained below based on an actual example shown in the drawings. As shown in Fig. 2, the main pipes 14, 14' are made of an insulating material with excellent resistance to plating liquid, such as Teflon or vinyl chloride.
(A pipe with a hollow center, hereinafter referred to as a pipe) and the secondary pipes 15 and 15' are made of similar materials, and the plating liquid flowing from above flows into the main pipes 14 and 14'. It passes through the secondary pipe 15 provided in the section and is recovered via the secondary pipe 15'. The main pipes 14, 14' have electrode connection fittings 16, 1.
6' is fixed, and electrodes 17, 17' made of conductive wires, rods, plates, etc. are connected. The end faces of the slave pipes 15, 15 connected to the main pipes 14, 14' are located at the main pipe 1.
4 and 14'. In the structure of the pipe parts described above, the plating liquid is supplied from above to the main pipes 14 and 14', and the main pipe 14 is adjusted so that the plating liquid pressure is high, and the main pipe 14' is adjusted so that the plating liquid pressure is low. The plating liquid is vigorously discharged from the main pipe 14 with high liquid pressure to the secondary pipe 15, and at the same time, it is sucked into the secondary pipe 15' connected to the main pipe 14' with low plating liquid pressure, and the electrode is applied to the stool. Connection fittings 16, 16', electrode 1
7 and 17' are working as anodes, and the parts through which the plating liquid passes, such as openings and notches of the material 18 to be plated, which are working as cathodes, are connected to the secondary pipe 1.
5, 15', the plating liquid 19 is vigorously discharged from the slave pipe 15.
Conducts contact with. After maintaining the state in which the material 18 to be plated and the plating liquid 19 are in contact with each other for several tens of seconds to several minutes, the material 18 to be plated is transferred to the secondary pipes 15, 15'.
By pulling away from the gap L, the slave pipe 15,
A plated material can be plated to have a cross-sectional shape substantially the same as that of 15'. When plating work is performed by such a method, it is assumed that plating liquid is present inside at least the secondary pipes 15 and 15', and the plating liquid is raised inside the main pipe 14 and is vigorously discharged from the secondary pipe 15. The plating liquid 19 is absorbed because the plating liquid pressure in the main pipe 14' is low. In this case main pipe 1
Sub pipe 15,1 protruding from 4,14'
The lengths l and l' of 5' are the inner diameters of the main pipes 14 and 14'.
1/3 or more is desirable. Further, it is desirable that the gap L between the slave pipes 15 and 15' be 1.5 to 2 times the thickness of the material to be plated 18, and the maximum width should be 1.5 mm. The above description is for the case where the slave pipes 15, 15' are placed horizontally, but the specifications do not change even if the slave pipes 15, 15' are rotated downward, upward, etc. As an example of satisfying the above conditions, the outer diameter of the main pipes 14, 14' is 10 mm, the inner diameter is 6 mm, the outer diameter of the slave pipe is 0.8 mm to 3.0 mm, the inner diameter is 0.4 mm to 2.5 mm, and the main pipe is pipe 14,1
Length l to end face of 4', l' is 3.5 mm, plating liquid temperature
45℃~70℃, plating liquid composition is Au (CN ₂ ) 20~30
g/, solution 75%, remaining pure water PH7.0-7.5, specific gravity
1.13 to 1.18, voltage 3v to 6v, voltage 4v to 6v, current density 5 to 10A/ ^dm2 , material to be plated 14 is phosphor bronze plated with Ni plating of about 1 μm, plating processing time 10 to 30 seconds. The gap width L between the slave pipes 15 and 15' is 1.5mm.As a result of plating under these conditions, the maximum width between the facing slave pipes is 1.5mm.
Plating processing is possible even as mm.

The area to which the plating liquid adhered is limited to a range of 0.5 mm to 2.8 mm, and there is no leakage or adhesion of the plating liquid to other areas.

The plating liquid flow rate in the main pipe is 1.0 to 1.5 m/sec,
At a voltage of 5V and a current density of 7A/ ^dm2 , the relationship between plating time and plating thickness is 1μm/5sec, 2μ
m/10sec and 4μm/20sec.

Plating was carried out using slave pipes with different inner diameters ranging from 0.3 mm to 2.5 mm, and sufficient plating was possible.

As described above, the partial plating method according to the present invention allows partial plating to be performed without covering the material to be plated with an elastic mask, resist, tape, or the like.

It is possible to arbitrarily apply plating to the required portions of the cross-sectional direction of the material to be plated, such as by bending or cutting up.

Changes in the plating position due to switching of the material to be plated can be handled by changing the nozzle setting position, allowing quick work.

When producing partial plating according to the present invention,
It is possible to make the structure extremely compact and easy to replace and adjust parts, and it is possible to realize downsizing and cost reduction of the machine.

Since the areas to which the plating liquid adheres are limited to only those areas that require plating, it is an economical method with very little pumping of the plating liquid.

There is no need to press the nozzle and the material to be plated,
Plating processing is possible just by inserting a gap.

As described above, the partial plating method according to the present invention includes:
It is most suitable for partial plating of small parts, such as electrically conductive parts used in wristwatches, table clocks, etc., and parts for small home appliances such as cameras, small tape recorders, etc. In addition, partial plating can be performed simply by placing the material to be plated between the facing pipes, so it is possible to perform partial plating by simply placing the material to be plated between the facing pipes. This method of plating is carried out in such a way that the liquid contacts and slides on the surface to be plated, and the anode installed inside the tip and the material to be plated act as a cathode. Difficult to replenish liquid,
This partial plating method has a wide range of applications and can be treated as a new plating method that satisfies all the problems such as the inability to partially plate small parts.

[Brief explanation of the drawing]

FIG. 1 shows a conventional partial plating method, and cross-sectional views showing each embodiment are shown in A, B, and C. (B) 1... Material to be plated, 2... Elastic body having through holes, 3... Elastic sheet, 4... Air cylinder, 5... Nozzle, 6... Plating treated part, 7... Holes Department. (c) 8... Plating processing portion, 9... Resist, 10... Material to be plated.
(c) 11... Plating treated portion, 12... Insulating tape, 13... Material to be plated. FIG. 2 shows a partial plating method according to the present invention. 14, 14'... Main pipe, 15, 15'... Sub pipe, 16, 16'... Electrode connection fitting, 17,
17'... Electrode, 18... Material to be plated, 19...
Metsuki liquid flowing through.

Claims (1)

[Claims] 1 A plurality of pipes are provided through which the plating liquid flows, and the above-mentioned
A portion of each pipe is provided with sub-pipes facing each other at approximately right angles, one sub-pipe is used as a plating liquid discharge pipe, and the other vertical pipe is used as a plating liquid suction pipe;
The plating liquid flowing through the pipe is discharged from one sub-pipe facing the plating liquid, and the plating liquid is sucked from the other sub-pipe, and a certain interval is provided between the end faces of the plurality of opposing sub-pipes. A material to be plated is placed in the space with the plating liquid flowing through the space, and with the material to be plated in wet contact, the plating liquid side is used as an anode and the side of the material to be plated is used as a cathode. A partial plating method characterized by performing partial plating on plating material.