JP2992645B2 - Method for producing electroformed product having through-hole - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing an electroformed product having a through hole.

[Conventional technology]

Examples of this type of electroformed product include various meshes (such as meshes for precision screen printing), electric razor blades, and various nozzles.

In the production of these electroformed products, particularly electroformed products having relatively thick through-holes, in many cases, for example, as shown in FIGS. First, as shown in FIG. 5 (a), a negative type photoresist 4 is superimposed on a plurality of layers on the surface of the electroformed mother die 3, and on the photoresist 4, a hole corresponding to a through hole of an electroformed product is formed. A film 5 having a desired pattern (network pattern) is closely adhered, baked, and developed to form a photoresist film 6 as shown in FIG. 5 (b). Next, as shown in FIG. 5 (c), metal 7 is electrodeposited on the surface of the electroformed mold 3 not covered with the photoresist film 6, and thereafter, as shown in FIG. 5 (d). By removing the electrodeposited metal 7 from the electroformed mold 3 and removing the photoresist film 6, an electroformed product having the through-hole 2 having an inverted trapezoidal cross section is obtained.

In order to obtain a relatively thick electroformed product (for example, 150 to 200 μm), a plurality of photoresist films 6 are superposed on the surface of the electroformed mold 3. The cross-sectional shape of the portion (corresponding to the hole) tends to be an inverted trapezoid in which the lower portion of the photoresist film 6 becomes thinner. The cause of this inverted trapezoidal shape is that, when the photoresist film 6 is overlaid with two or three layers, light rays (ultraviolet rays) are absorbed exponentially. Is not reached. It has been found that such an inverted trapezoidal tendency becomes more remarkable as a photoresist having a lower light transmittance is used alone.

[Problems to be solved by the invention]

Based on such knowledge, the present invention skillfully utilizes the tendency of the photoresist film to be inverted trapezoid, and seeks to obtain an electroformed product that requires such a cross-section inverted trapezoidal through-hole, for example, a nozzle electroformed product. is there.

However, in the thick photoresist film 6 described above, the amount of light (ultraviolet rays) reaching the lower layer portion is small, and the lower layer portion tends to become an uncured film due to the surface hardening. Are easily peeled from the electroformed mold 3 to cause defects. Therefore, it is difficult to obtain an electroformed product having the through-hole 2 having a constant inverted trapezoidal cross section with the photoresist film 6 described above. In addition, the nozzle,
In particular, it is not suitable for an object such as a nozzle for an ink jet printer which needs to jet ink uniformly and parallel to an ejection target with high accuracy.

In view of this, the present invention has an inverted trapezoidal portion 2a at the upper part and a thin vertical part 2b at the outlet side at the lower part of the cross-sectional shape of the through-hole 2, so that it is optimal for a nozzle, particularly a nozzle for an inkjet printer. An object of the present invention is to provide a method for manufacturing a cast product.

[Means for solving the problem]

As shown in FIGS. 1 (a) and 1 (b), the present invention provides a negative type photoresist film having a pattern (pattern) corresponding to a through hole of an electroformed product on the surface of an electroformed mold 3. 6 is formed, and a metal 7 is electrodeposited on the surface of the electroforming mold 6 that is not covered with the photoresist film 6, and the electrodeposited metal 7 is peeled off from the electroforming mold 3 to form a through hole. In the manufacturing method for obtaining an electroformed product having a shape 2, the photoresist film 6 is formed of a plurality of layers of a photoresist having a large light transmittance and a photoresist having a small light transmittance, and is in contact with the surface of the electroformed mold 3. A photoresist 4a having a high light transmittance is used in the lower layer on the side.

[Action]

Since the photoresist 4a having a high light transmittance is used in the lower layer portion in contact with the surface of the electroformed mold 3, the light beam sufficiently reaches the lower layer portion of the photoresist film 6, and the light is transmitted to the electroformed mold 3 of the photoresist 4a. The contact surface of can be cured sufficiently,
It is less likely that the lower layer portion of the photoresist film 6 is peeled off from the electroforming mold 3 and is damaged.

In addition, by using a photoresist film 4a having a high light transmittance in the lower layer portion, the light beam is transmitted almost vertically in the photoresist 4a, so that a thin vertical portion 6b is formed below the inverted trapezoidal portion 6a. Thus, a photoresist film 6 can be obtained. Therefore, when electroforming using this photoresist film 6, it is possible to obtain an electroformed product having the through-hole 2 having a cross section having a narrow vertical portion 2b below the inverted trapezoidal portion 2a. In 2b, a fluid such as ink can be jetted uniformly and parallel.

〔The invention's effect〕

According to the present invention, since the cross-sectional shape of the through hole 2 of the electroformed product having the through hole can be obtained in a shape having a thin vertical portion 2b below the inverted trapezoidal portion 2a, a nozzle, particularly for an ink jet printer Advantageously, an electroformed product suitable for an object such as a nozzle, which needs to eject ink or the like uniformly and parallel to an ejection target, or a similar product, can be easily manufactured.

〔Example〕

One embodiment of a method for manufacturing an electroformed product according to the present invention will be described with reference to FIGS. 1 (a) to 1 (f), FIGS. 2, 3 and 4.

FIG. 2 shows a nozzle for an ink jet printer, which is an example of the electroformed product, in which a large number of through holes 2 are formed in a nozzle body 1 (100 μ thick) having a thin rectangular plate shape. As shown in FIG. 3, the cross-sectional shape of the through-hole 2 has a shape in which an inverted trapezoidal portion 2a is formed in the upper portion and a thin vertical portion 2b is formed in the lower portion (outlet side).

An electroformed product having the through-hole 2 having such a cross-sectional shape is manufactured through the following steps.

First, as shown in FIG. 1 (a), a plurality of negative-type film-shaped photoresists 4 (four layers 4a, 4b, 4c, 4d in the illustrated example) are formed on the surface of a stainless steel electroformed mold 3. By superimposing, for example, a 200 μm thick film is formed. In this case, of the four layers, the photoresist on the side in contact with the surface of the electroformed mold 3
4a (50μ thickness) is the other three layers of photoresist 4b, 4c, 4d
Used is larger than the light transmittance of

FIG. 4 shows the ultraviolet transmission characteristics of the three types of photoresists (thickness: 50 μl, cross-section A: when four layers are superimposed).
As 4a, for example, a trade name of Nippon Gohsei Chemical Co., Ltd .; Nichigo ALPHO-321Y50, and as the photoresist films 4b, 4c, 4d with low light transmittance, for example, the trade names of Nippon Gohsei Chemical Co., Ltd .; Select ALPHO-1150MY or Nippon ALPHO-111Y50. Incidentally, in FIG. 4, the wavelength 365 nm is the peak of the ultraviolet wavelength of the ultraviolet lamp, and the light of this wavelength is emitted most. Therefore, many photoresists have a curing wavelength peak at 365 nm.

Next, as shown in FIG.
A film 5 having a pattern (pattern) corresponding to the through hole of the electroformed product is brought into close contact with the film, and as shown in FIG. 1C, irradiation with an ultraviolet lamp, baking, development, and drying are performed. . At this time, the photoresist 4d
The light rays are gradually absorbed by the 4c layer, and the inverted trapezoid becomes remarkable from around the 4b layer to form a photoresist film 6 as shown in FIG. 1 (d). This photoresist film 6
The photoresist 4b, 4c, 4d having a low light transmittance has an inverted trapezoidal section 6a in the upper layer, and the photoresist 4a having a high light transmittance has a vertical section 6b in the lower layer. Next, the electroformed mold 3 is transferred to an electrodeposition bath, electroformed with nickel or a nickel-cobalt alloy, and covered with a photoresist film 6 of the electroformed mold 3 as shown in FIG. Metal 7 is electrodeposited on the uncoated surface to a height (100 μ) of the second layer of the photoresist film 6.

After the electroforming, the electrodeposited metal 7 and the photoresist film 6 are peeled off from the electroforming matrix 3 and the photoresist film 6 is removed, so that the cross-sectional shape as shown in FIG. Electroformed product 9 having through-hole 2 consisting of 2a and narrow vertical portion 2b
Get.

(Another embodiment)

In the above embodiment, a film-like resist is used as the photoresist 4 formed on the surface of the electroformed mold 3. Instead, a liquid photoresist is sequentially applied to a plurality of layers and dried to form a thick photoresist. May be formed.

[Brief description of the drawings]

FIGS. 1 (a) to 1 (f), FIGS. 2, 3 and 4
FIG. 1 shows an embodiment of a method of manufacturing an electroformed product according to the present invention, wherein FIGS. 1 (a) to 1 (f) are process explanatory views of a manufacturing process, FIG. 2 is a perspective view of an electroformed product, FIG. 3 is an enlarged cross-sectional view of a through-hole portion of the electroformed product shown in FIG. 2, and FIG. 4 is a view showing ultraviolet transmission characteristics of various photoresists. FIGS. 5 (a) to 5 (d) are process explanatory diagrams of a process of manufacturing a conventional electroformed product. 2 ... through-hole, 3 ... electroforming matrix, 4 ... photoresist, 6 ... photoresist film, 7 ... electrodeposited metal, 9 ... electroformed product.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihiro Kobayashi 4680 Ikata, Fukuoka-machi, Fukuoka Prefecture Inside Kyushu Hitachi Maxell Co., Ltd. (56) References JP-A-64-62491 (JP, A) (58) Surveyed field (Int.Cl. ⁶ , DB name) C25D 1/00-3/66 C25D 5/00-7/12

Claims (1)

(57) [Claims] 1. A negative type photoresist film (6) having a pattern corresponding to a hole of an electroformed product is formed on the surface of an electroformed mold (3). After the metal (7) is electrodeposited on the surface not covered with the photoresist film (6), the electrodeposited metal (7) is peeled off from the electroformed mold (3) to form an inverted trapezoidal through hole. The method for producing an electroformed product having (2), wherein the photoresist film (6) comprises a plurality of layers of a photoresist having a large light transmittance and a photoresist having a small light transmittance, and the electroforming matrix (3). By using the photoresist (4a) having the higher light transmittance in the lower layer on the side in contact with the surface of the film, the upper part of the through-hole (2) is formed in an inverted trapezoidal shape in the upper layer of the photoresist film (6). The lower part of the photoresist film (6), which communicates with the upper part of the through hole (2), is vertically Respectively and forming method of electroforming products having a through hole on.