JPS6053759B2 - Partial plating method and device - Google Patents

Description

[Detailed Description of the Invention] The present invention is applicable to partial plating, particularly to materials to be plated (such as lead frames for integrated circuits) that have gaps in the plating target area.
The present invention relates to a partial plating method and apparatus for plating.

The plating process for plated materials such as lead frames is
High-speed partial plating methods and equipment that apply a jet stream of plating solution to the material to be plated are widely used due to various advantages.
Most of the plating treatments are gold or other noble metal plating.

In such high-speed partial plating, the parts to be plated on the material to be plated are sectioned and exposed by masking, and masking technology is extremely important from the viewpoint of clarifying the plated and non-plated parts and improving economic efficiency. Ru. By the way, if the material to be plated has no gaps, normal masking can be used, but if the material to be plated has gaps, it may be necessary to stop the plating solution from entering into the gaps, or it may be difficult to mask individually. It is necessary to obtain a mask body that matches the shape and structure of the material to be plated, and to form a convex portion on the mask body that can fit into the gap. In the former case, wasteful use of expensive gold and other precious metal plating solutions cannot be prevented, and in the latter case, a special mask is required to match the shape and structure of the part to be plated, especially the shape and structure of the gap. The disadvantage is that the body must be created. The present invention is a partial plating method and device developed with the above-mentioned points in mind, and its intended purpose is not only to apply a mask body to the surface of the non-plated part, but also to apply the mask body to the surface of the non-plated part. The purpose is to introduce and spray air to prevent the plating solution from entering or adhering there.Specifically, the part to be plated with a gap in the material to be plated is sectioned and exposed using a mask body with openings, and then the plating is applied to that area. In a partial plating method in which the liquid is injected from a nozzle, an air nozzle is placed on the back and/or front side of the part to be plated, and air is injected into the gap when the plating liquid is injected. The purpose of the present invention is to provide a partial plating method characterized in that the plating solution is prevented from entering the plating device, and further includes a plating device main body equipped with a plating solution injection nozzle, and a plating device main body equipped with a plating solution injection nozzle. a front side mask means with an opening for partitioning and exposing the part to be plated in the gap of the material to be plated;
A back side mask means that is arranged opposite to the front side mask means and has a backing part that is brought into close contact with a corresponding part of the back surface of the part to be plated, and an air injection part that is formed at a position surrounding this backing part. It is an object of the present invention to provide a partial plating apparatus comprising: and pressing means for moving the back side mask means toward and away from the front side mask means.

The details will be described below based on the drawings. Reference numeral 1 includes a plating liquid spray nozzle 2 disposed upward inside the plating apparatus main body.

This injection nozzle 2 has an anode 3 at its tip. A front mask means 4 is disposed above the plating solution spray nozzle 2, that is, on the plating solution spray side. The front side mask means 4 is composed of a base body 5 which constitutes the upper cover of the plating apparatus main body 1 on one side and which receives pressure from a pressing means (described later) on the other hand, and a mask body 6 fixedly provided on the upper surface side of the base body 5. Be. The base body 5 has a spray opening 8 with an inclined surface 7 for guiding the smooth flow of the plating solution, and the mask body 6 communicates with this spray opening to direct the plating target area A of the plated material 9. It has an opening 10 that exposes the section. The base body 5 and the mask body 6 are integrated in advance. Also, it is optional to remove the role of the upper cover from the base body 5. A back side mask means 11 is arranged opposite to such a front side mask means 4. The back mask means 11 is provided with a backing part 12 and an air injection part 13,
A feature of the present invention is that the back side masking means 11 is used in combination with the front side masking means 4. Backing part 1
2 is a part that can be brought into close contact with a corresponding part on the back side of the part A to be plated, preferably a corresponding part on the back side which is slightly larger in size than the part to be plated on the front side, and has an area corresponding to the part to be plated. The air injection part 13 serves as an air nozzle and is formed at a position surrounding this backing part 12, and corresponds to at least a part of the gap 14 of the plating target part A [the communicating part of the gap 14]. formed into position. By the way, in the illustrated example,
This back side mask means 11 includes a back side mask body 15 and a presser plate 1.
6, the center part of the back mask body 15 serves as the above-mentioned backing part 12, and the outside thereof becomes the above-mentioned air injection part 13.
The remaining portion forms a pressing portion 17. The press plate 16 has the back side mask body 15 fixedly attached to its lower surface side, and has an air supply path 18 communicating with the air injection section 13 . The back side mask body 15 and the presser plate 16 may be integrated in advance, and the air supply path 18 may be formed in any manner. Reference numeral 19 denotes a pressing means such as a pressure cylinder, which moves the back side mask means 11 toward and away from the front side mask means 4.

By the way, it is possible to form an air injection part in the above-mentioned front side mask means 4, and to explain this point with reference to FIG. Air injection portions 13a are formed in each of the portions 6a.

The air injection part 13a constitutes a ring-shaped nozzle and is provided at a position surrounding the opening 10a. Note that this air injection section 13a may be used in combination with the air injection section 13 of the back side mask means 11, or may be used selectively.In short, it introduces and injects air into the gap in the part to be plated of the material to be plated. It is sufficient to use the air injection section 13 and/or 13a which is easier. Next, details of the material to be plated 9 will be described, as well as the operation of the partial plating apparatus and the partial plating method.

The plated material 9 shown in the figure is a schematic representation of a lead frame, in which gold plating is applied to a part of the mounting part 20 of the element and the part 21 to be bonded with a thin metal wire, and there is a complicated structure between each part. A shaped gap 14 is left.

This material to be plated 9 is placed on the front side mask body 6, and the pressing means 19 is activated to press the back side mask body 15 downward in FIG. The plating process is carried out under the following conditions. Plating liquid is sprayed from spray nozzle 2
However, prior to that, the air continues to be ejected from the air injection part 13 that constitutes the air nozzle. The injected air passes through the gap 14 and reaches the front side (
It is ejected to the bottom side of Figure 1). On the other hand, the plating liquid sprayed upward from the spray nozzle 2 reaches the plating target part A of the plated material which is sectioned and exposed by the opening 10 of the mask body 6 on the front side, and the plating liquid inside the plating target part A. It is deposited only on the exposed front surface of the material, but its penetration into the gap 14 is blocked and prevented by the opposing air jets. Furthermore, at this time,
Air can also be introduced and injected into the gap 14 from the air injection part 13a of the front side mask means 4a, and can be used in combination with or selectively with the air injection part 13. Therefore, the plating solution is not applied to the side surface portion corresponding to the wall thickness of the portion 21 that is bonded to the mount portion 20. No matter how complex the shape or structure of the gap, the injected air passes through it and escapes from the back side to the front side, so the plating solution cannot penetrate into the gap. Also, of course, it does not diffuse within one gap or flow into the 0 gap area other than the area to be plated between the front and back mask bodies. In order to make this state easier to understand in the drawing, the part masked by the backing part 12 is shown as ? The part to which the air injection part 13 is applied is shown by \, and the part to which the plating solution is applied is shown by Z. Note that the portion indicated by I in FIG. 3 indicates a plated portion. As explained above, according to the method and apparatus of the present invention, the existence of opposing air flows prevents the infiltration of the plating liquid flow. Even if there is a problem, the air flow will flow into that area and prevent the plating liquid flow from entering, allowing accurate masking even on minute parts. No plating is applied to the parts, and the leakage of the plating solution to areas other than those to be plated is of course prevented, which reduces wasteful use of the plating solution and clarifies the boundaries between non-plated parts and plated parts. The configuration and formation of the air nozzle placed on the back and/or front side of the target part is relatively easy and easy to manufacture as a device.Moreover, it can be incorporated into a conventional jet stream spot plating device, making it highly versatile and easy to use. It has many advantages such as rapid plating processing because no masking processing is required.

Further, these effects can be fully expected even when the method and apparatus of the present invention are applied to a type of partial plating method and apparatus in which a plating solution is sprayed horizontally.

[Brief explanation of drawings]

FIG. 1 is a sectional view schematically showing an example of the device of the present invention, and FIG.
The figure is an explanatory diagram showing the positional relationship between the material to be plated and the plating solution injection opening viewed from the direction ■ in Figure 1, and Figure 3 is the position of the material to be plated and the air injection part viewed from the direction ■ in Figure 1. FIG. 4 is an explanatory diagram showing the opposing state of the plating solution and air flow within the gap, and FIG. 5 is a partial sectional view of the front side mask means showing a modification of the air injection part.

Claims (1)

[Scope of Claims] 1. In a partial plating method in which a plating target part with a gap in a plating material is sectioned and exposed using a mask body with an opening, and a plating solution is sprayed thereon from a nozzle, the plating target part Partial plating characterized in that an air nozzle is disposed on the back side and/or the front side of the plate to inject air into the gap when the plating liquid is injected to prevent the plating liquid from entering into the gap. Method. 2. A plating device body equipped with a plating liquid spray nozzle,
A front side mask means is placed on the spraying side of the plating solution and has an opening for partitioning and exposing the part to be plated with a gap in the material to be plated, and a part placed opposite to the front side mask means is the part to be plated. a back side mask means having both a backing part that is brought into close contact with a corresponding part of the back side and an air injection part formed at a position surrounding the backing part, and the back side mask means is brought close to and separated from the front side mask means. A partial plating device comprising a pressing means. 3. The partial plating apparatus according to claim 2, wherein the front side mask means has an air injection section formed at a position surrounding the opening thereof.