JPH04218690A - Production of electroformed product having through-hole - Google Patents

Abstract

PURPOSE:To obtain a electroformed product optimum for the nozzle for an ink jet printer and the shadow mask of a cathode-ray tube by etching the surface of an electrodeposited metal after electroforming while an electroforming photoresist is put on an elelctroforming matrix. CONSTITUTION:A photoresist film 6 having a pattern corresponding to the through-hole of an electroformed product is formed on the surface of an electrocasting matrix 3, then a metal 7 is elelctrodeposited on the surface of the matrix 3 not covered with the film 6, the surface of the elelctrodeposited metal 7 is etched while the film 6 is put on the matrix 3, the metal 7 is released from the matrix 3, and then the film 6 is removed to obtain an electroformed product having a through-hole 2 having a funneled inlet part 2a and a small- diameter tubular outlet part 2b.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing electroformed products having through holes.

0002

2. Description of the Related Art Electroformed products of this type include, for example, various meshes such as precision screen printing meshes, electric razor blades, and various other nozzles. These electroformed products are especially relatively thick (e.g. 15
When manufacturing an electroformed product having a through hole of 0 to 200 μm, in many cases, for example, as shown in the process diagram of the manufacturing process, first, as shown in FIG. A plurality of layers of negative photoresist 4 are superimposed on the surface of the casting mold 3, and a film 5 having a pattern (mesh pattern) corresponding to the through holes of the electroformed product is adhered onto the photoresist 4. By baking and developing, a photoresist film 6 is formed as shown in FIG. 5(B). Next, as shown in FIG. 5C, a metal 7 is electrodeposited on the surface of the electroforming mold 3 that is not covered with the photoresist film 6, and then,
As shown in FIG.
By peeling it off and removing the photoresist film 6, an electroformed product having through holes 2 is obtained.

The cross-sectional shape of the through hole 2 thus obtained tends to be an inverted trapezoid. This is because by stacking the photoresist film 6 in two or three layers, light (ultraviolet light) is absorbed exponentially, and as a result, almost no light rays reach the position of the electroforming mold 3. This is thought to be the cause. This tendency of inverted trapezoid formation becomes more pronounced as a photoresist with lower light transmittance is used.

0004

[Problems to be Solved by the Invention] However, the through hole 2 having an inverted trapezoidal cross section is difficult to use in a nozzle, for example, in a nozzle for an inkjet printer, in which ink is ejected in a uniform flow parallel to the object with high accuracy. Not suitable for things that need to be squirted.

[0005] Therefore, the present invention aims to provide a manufacturing method capable of producing an electroformed product having a through hole with a cross-sectional shape that is optimal for use in nozzles for inkjet printers and the like.

[0006]

[Means for Solving the Problems] As illustrated in FIG. 1, the present invention provides a photoresist film 6 having a pattern corresponding to the through holes of an electroformed product on the surface of an electroforming matrix 3. a step of electrodepositing metal 7 on the surface of the electroforming mother mold 3 that is not covered with the photoresist film 6;
Electrodeposited metal 7 with photoresist film 6 still attached to
After the etching, the electrodeposited metal 7 is peeled off from the electroforming mold 3 and the photoresist film 6 is removed. An electroformed product having a through hole 2 formed in a shape communicating with a narrow pipe-like outlet portion 2b is obtained.

[0007]

[Operation] By electrodepositing the metal 7 on the surface of the electroforming matrix 3 that is not covered with the photoresist film 6, the conduit-shaped outlet portion 2b can be formed at the location corresponding to the photoresist film 6. . At this time, as shown in FIG.
Although the photoresist film 6 is carried out in a straight line as shown in
In the vicinity of , electrodeposition is performed not only in a straight line but also by going around the surface of the photoresist film 6 as shown by arrow n, so that the amount of electrodeposition increases locally, resulting in a thickened area with a high current density. 7a (dendritic growth phenomenon) occurs.

The high current density portion on the surface of the electrodeposited metal 7 is likely to be intensively corroded by etching in the next step, and as a result, the funnel-shaped lead-in portion 2a, which has a larger diameter than the conduit-shaped outlet portion 2b, is formed by etching. It can be formed in communication with the pipe-like outlet portion 2b. During this etching, no etching photoresist is intentionally required.

[0009]

According to the present invention, it is possible to obtain a cross-sectional shape of the through hole 2 of an electroformed product such that the conduit-like outlet portion 2b communicates with the narrow-diameter outlet side of the funnel-like guiding portion 2a. The fluid such as ink that is drawn in by the funnel-shaped guiding part 2a can be ejected in a uniform flow in the region of the pipe-like outlet part 2b. Compared to conventional electroformed products that have trapezoidal holes, nozzles, especially nozzles for inkjet printers, which need to eject ink uniformly, parallelly, and with high accuracy to the object to be ejected, or It is advantageous that electroformed products suitable for similar products such as cathode ray tube shadow masks can be easily produced.

0010

[Embodiment] An embodiment of the method for manufacturing an electroformed product according to the present invention will be described with reference to FIGS. 1 to 3. FIG. 2 shows an inkjet printer nozzle as an example of the electroformed product, in which a large number of through holes 2 are formed in a rectangular thin plate-shaped nozzle body 1 (80 μm thick). As shown in FIG. 3, the cross-sectional shape of the through hole 2 is composed of a funnel-shaped lead-in part 2a and a narrow conduit-like outlet part 2b formed in communication with the narrow diameter outlet side of the funnel-shaped lead-in part 2a. have.

An electroformed product having a through hole 2 having such a cross-sectional shape is manufactured through the following steps. First, as shown in FIG. 1A, a plurality of layers (four layers in the illustrated example) of negative film-like photoresist 4 are superimposed on the surface of a stainless steel electroforming master mold 3. Forms a uniform thick film. As the photoresist 4, it is preferable to use one having a high light transmittance, for example, Nippon Gosei Kagaku Kogyo Co., Ltd., trade name: Nippon ALPHO-321Y50.

Next, as shown in FIG. 1B, a pattern (corresponding to the through holes of the electroformed product) is formed on the photoresist 4.
A photoresist film 6 (200μ thick) is formed as shown in FIG.
form. Since this photoresist film 6 uses the photoresist 4 having a high light transmittance, the photoresist film 6 can be formed almost vertically and has excellent adhesion to the surface of the electroforming matrix 3.

Next, the electroformed mother mold 3 is transferred to an electroforming bath such as a nickel sulfamate bath, and electroformed with nickel or nickel-cobalt alloy to form an electroformed mother mold as shown in FIG. 1(D). Metal 7 is electrodeposited on the surface of mold 3 that is not covered with photoresist film 6 to about the thickness of photoresist film 6. At this time, in the vicinity of the photoresist film 6 on the surface of the electrodeposited metal 7, in addition to the straight electrodeposition shown by the arrow m,
Since it is also electrodeposited by going around the surface of the photoresist film 6 as shown by arrow n, a dendritic growth phenomenon occurs at this location, resulting in a thickened portion 7a with a high current density.

Next, as shown in FIG. 1E, the surfaces of the electrodeposited metal 7 and photoresist film 6 are polished to a uniform thickness (150 μm). This polishing step can also be omitted.

Next, the entire structure was immersed or spray etched in a corrosive solution such as ferric chloride, and as shown in FIG.
As shown in (F), the surface of the electrodeposited metal 7 is chemically corroded. At this time, high current density areas near the photoresist film 6 on the surface of the electrodeposited metal 7 are concentrated and locally corroded, forming a funnel shape. The etching depth and diameter are adjusted by the etching time.

After etching, the electrodeposited metal 7 and the photoresist film 6 are peeled off from the electroforming mold 3, and the photoresist film 6 is removed by immersing it in a sodium hydroxide stripping bath or the like. G) and an electroformed product 9 having a through hole 2 having a cross-sectional shape as shown in FIG.

In the above embodiment, a film resist is used as the photoresist 4 formed on the surface of the electroforming mother mold 3, but instead of this, multiple layers of liquid photoresist are sequentially applied and dried. A thick photoresist film 6 can also be formed.

FIG. 4 is a process explanatory diagram of a manufacturing process showing another embodiment. In this embodiment, the cross-sectional shape of the through hole 2 is different from the above embodiment, and the pipe-like outlet portion 2b is formed in parallel in the above embodiment, whereas in this embodiment, the (E
) is different in that it is formed in a tapered shape. The through hole 2 having such a cross-sectional shape is manufactured as follows. First, a photoresist 4 with low light transmittance is applied to the surface of the electroforming matrix 3, such as Nippon Gohsei Chemical Industry Co., Ltd.'s product name: Nippon ALPHO-1150MY or Nippon ALP.
Layer multiple layers of HO-111Y50. Next, in the same manner as shown in FIG. 1B of the above embodiment, a film 5 having a pattern corresponding to the through holes of the electroformed product is closely adhered to the top layer of photoresist 4, baked with ultraviolet rays, and developed. A photoresist film 6 as shown in FIG. 4A is formed by performing the following processes. Since this photoresist film 6 uses only the photoresist 4 with low light transmittance, it becomes difficult for light rays to reach the surface of the electroforming mold 3, and as a result, the cross-sectional shape of the photoresist film 6 is formed into an inverted trapezoid. be able to. After forming the photoresist film 6 having an inverted trapezoidal cross section in this manner, metal 7 is electrodeposited on the surface of the electroforming mold 3 that is not covered with the photoresist film 6, as in the above embodiment. (B) in FIG. 4), and then the surfaces of the electrodeposited metal 7 and the photoresist film 6 are polished ((C) in FIG.
), and then the surface of the electrodeposited metal 7 is etched ((
D)) Finally, the electrodeposited metal 7 is peeled off from the electroforming mold 3 and the photoresist film 6 is removed. Thus, (E) in Figure 4
As shown in FIG. 2, it is possible to obtain an electroformed product 9 having a through hole 2 that communicates a tapered pipe-like outlet portion 2b with a funnel-like guiding portion 2a.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a manufacturing process.

FIG. 2 is a perspective view of an electroformed product.

FIG. 3 is an enlarged sectional view of a through-hole portion of the electroformed product.

FIG. 4 is a process explanatory diagram of a manufacturing process showing another embodiment.

FIG. 5 is a process explanatory diagram of a manufacturing process of a conventional electroformed product.

[Explanation of symbols]

2 Through hole 2a Funnel-shaped lead-in part 2b Pipe-like outlet part 3 Electroforming mother mold 4 Photoresist 6 Photoresist film 7 Electrodeposited metal 9 Electroformed products

Claims (1)

[Claims] 1. A step of forming a photoresist film 6 having a pattern corresponding to the through holes of the electroformed product on the surface of the electroforming mother mold 3, and a step of forming a photoresist film 6 on the surface of the electroforming mother mold 3, a step of electrodepositing the metal 7 on the surface where the electrodeposited metal 7 is not present, a step of etching the surface of the electrodeposited metal 7 with the photoresist film 6 still attached to the electroforming mold 3, and a step of electrodepositing the electrodeposited metal 7 after the etching. A method for producing an electroformed product having through-holes, the method comprising the steps of peeling off from a casting mold 3 and removing a photoresist film 6.