Electroforming master, method for producing metal formed product, and metal formed product

Abstract

Provided is a master for electroforming, the master being for manufacturing a metal formed product having a hole. The master for electroforming has, on the surface, an insulating mask for forming the hole of the metal formed product. The mask includes a ring-shaped mask that, in a plan view, has a contour corresponding to the outline of the hole and has an inner hole part. Provided also are a method for producing a metal formed product and the metal formed product.

Description

Master disk for electroforming, method for manufacturing a metal formed article, and metal formed article

[0001] The present disclosure relates to a master disk for electroforming, a method for manufacturing a metal formed article, and a metal formed article.

[0002] A method for manufacturing a metal formed article for manufacturing a metal formed article having a plurality of openings using electroforming technology is known (see, for example, Japanese Patent Application Laid-Open No. 08-142334). In the method for manufacturing a metal formed article described in Japanese Patent Application Laid-Open No. 08-142334, a master disk for electroforming in which a non-conductive mask is formed on a part of a substrate having a conductive surface is used, and a metal layer is grown on the conductive surface immersed in an electroforming solution, and an electroforming process for forming through holes (hereinafter simply referred to as "holes") at positions corresponding to the mask is included. By performing the electroforming process, a metal formed article having through holes is manufactured.

[0003] In Japanese Patent Application Laid-Open No. 08-142334, as a metal formed article, a nozzle plate used for a recording head of an inkjet printer is manufactured. The nozzles record dots corresponding to pixels, which are components of an image to be printed, by discharging ink.

[0004] The nozzle plate is a thin metal plate in which a plurality of through holes functioning as nozzles for ink ejection are arranged one-dimensionally or two-dimensionally. And the nozzle plate may have positioning holes when attaching the nozzle plate to the recording head main body.

[0005] When manufacturing a metal formed article having holes such as a nozzle plate by electroforming, since current concentrates on the periphery of the holes, the thickness becomes thicker at the periphery of the holes than in the region away from the holes.

[0006] In view of the above circumstances, an object of the present disclosure is to provide a master disk for electroforming and a method for manufacturing a metal formed article that can suppress the increase in thickness at the periphery of holes when manufacturing a metal formed article by electroforming. Further, an object of the present disclosure is to provide a metal formed article in which thickness non-uniformity is suppressed.

[0007] The electroforming master plate of this disclosure is an electroforming master plate for manufacturing a metal molded product having holes, and has an insulating mask on its surface for forming holes in the metal molded product, and the mask includes a ring-shaped mask whose shape, when viewed from above, has a contour corresponding to the contour of the hole and is ring-shaped with a hole on the inside.

[0008] The electroforming master plate of this disclosure is an electroforming master plate used to manufacture a metal molded product having a body thickness of D [μm], wherein the ring-shaped mask is a protrusion that protrudes from the surface on which the electroformed metal is electroformed, and it is preferable that when the ring width of the ring-shaped mask is w [μm] and the thickness is d [μm], w > 2(D - d).

[0009] The electroforming master plate of this disclosure preferably satisfies the condition w < 4(D-d).

[0010] In the electroforming master plate of this disclosure, it is preferable that the ring width of the ring-shaped mask is 450 μm or less.

[0011] The electroforming master plate of this disclosure may have a ring-shaped mask that is stepped in shape, such that the center portion of the ring width in the width direction of the ring-shaped mask protrudes more from the edges in the width direction of the ring width.

[0012] The electroforming master plate of this disclosure may have a ring-shaped mask in which the ring width is narrower in some parts than in other parts.

[0013] The electroforming master plate of this disclosure preferably has an internal mask which is positioned in the hole portion of the ring-shaped mask at a distance from the ring-shaped mask.

[0014] The internal mask may be similar in shape to the ring-shaped mask.

[0015] The internal mask may include multiple fine masks.

[0016] The electroforming master plate of this disclosure is used to manufacture a metal molded product having a small hole with an opening width smaller than that of the hole, and the mask may include a small hole mask having a contour corresponding to the contour of the small hole, which is positioned differently from the ring-shaped mask.

[0017] The present disclosure is a method for manufacturing a metal molded product having a hole, comprising an electroforming step using an electroforming master plate having an insulating mask on its surface for forming a hole in the metal molded product, wherein the mask is a ring-shaped mask whose shape in plan view has a contour corresponding to the contour of the hole and has a hole portion on the inside, and a peeling step for peeling the electroformed product formed in the electroforming step from the electroforming master plate.

[0018] In the electroforming process, it is preferable to perform electroforming under the condition that the body thickness D [μm] of the electroformed product formed by electroforming satisfies the condition w > 2(D - d), where w [μm] is the ring width of the ring-shaped mask and d [μm] is the thickness.

[0019] In the electroforming process, it is preferable to carry out the electroforming under the condition that w < 4(D-d).

[0020] In the peeling process, when peeling off the metal molded product, the electroformed material formed in the holes of the ring-shaped mask may be left on the electroforming master plate while the metal molded product is peeled off.

[0021] In the electroforming process, an electroforming master plate is used in which the ring width of the ring-shaped mask is formed to be narrower in some parts than in other parts, and in the peeling process, when peeling off the metal molded product, the electroformed material formed in the holes of the ring-shaped mask may be peeled off together with the metal molded product.

[0022] The metal molded product of this disclosure is made of electroformed material and has a plurality of holes with different opening widths, wherein the thickness of the periphery of the hole with the largest opening width is h1 [μm], the thickness of the periphery of the hole with the smallest opening width is h2 [μm], and the thickness of the main body is D [μm], and the condition (h1 - h2) / D < 0.1 is satisfied.

[0023] According to this disclosure, it is possible to provide an electroforming master plate that can suppress the increase in thickness at the periphery of holes when manufacturing metal molded products by electroforming, and a method for manufacturing metal molded products. Furthermore, according to this disclosure, it is possible to provide metal molded products in which thickness non-uniformity is suppressed.

[0024] This is a perspective view showing an example of a metal molded product. Figure 2A is an end view of the section between lines IIA and IIA of the metal molded product shown in Figure 1, and Figure 2B is an end view of the section between lines IIB and IIB of the metal molded product shown in Figure 1. This is a plan view showing a part of the electroforming master plate. This is an end view of the section between lines IV and IV of the electroforming master plate shown in Figure 3. This is a diagram showing the manufacturing process of the electroforming master plate. This is a diagram showing the manufacturing process of a metal molded product. This is a diagram to explain the problems of conventional electroforming master plates. This is a diagram to explain the effects of the electroforming master plate of the embodiment. This is an explanatory diagram of a modified positioning mask. This is an explanatory diagram of a modified positioning mask. This is an explanatory diagram of a modified positioning mask. This is an explanatory diagram of a modified positioning mask. This is an explanatory diagram of a modified positioning mask. This is a diagram to explain the results of a verification test.

[0025] Embodiments of this disclosure will be described below with reference to the drawings. In each drawing, the same components are denoted by the same reference numerals. Note that the scale of each component in the drawings has been appropriately changed from the actual dimensions for ease of viewing.

[0026] <Metal Formed Product> Figure 1 shows an example of a metal formed product made from electroformed material. In this example, the metal formed product is a nozzle plate 10 used in the inkjet head of an inkjet printer. The nozzle plate 10 is manufactured by a metal formed product manufacturing method using an electroforming master plate, which will be described later.

[0027] The nozzle plate 10 is a rectangular plate-shaped member made of electroformed metal such as nickel (Ni), and has a plurality of holes 11 and 12 with different opening diameters.

[0028] The relatively small holes 12 function as nozzles (hereinafter referred to as nozzles 12) and are formed in a two-dimensional arrangement. The nozzles 12 are formed in a substantially circular shape, and their diameter A2 is, for example, 100 μm or less, preferably 20 μm to 50 μm. In the recording head, the nozzle plate 10 is positioned such that its long direction corresponds to the main scanning direction X of the inkjet printer and its short direction corresponds to the sub-scanning direction Y. The length of the nozzle plate 10 in the main scanning direction is, for example, 100 mm, and the length in the sub-scanning direction is, for example, 40 mm. In this example, eight rows of nozzles, each containing 130 nozzles 12 arranged at regular intervals in the main scanning direction X of the nozzle plate 10, are provided in the sub-scanning direction Y.

[0029] The relatively large holes 11 are positioning holes (hereinafter referred to as positioning holes 11) used when attaching the nozzle plate 10 to the main body of the recording head. In Figure 1, two positioning holes 11 are shown provided at one end of the nozzle plate 10 in the longitudinal direction, but positioning holes 11 are provided at at least four corners of the nozzle plate 10. The positioning holes 11 are formed in a rectangular shape with rounded corners, and their opening width A1 is, for example, on the order of millimeters. The opening width A1 of the rectangular positioning hole 11 is defined by the longest distance between opposing sides. In this specification, if the plan view shape of the hole in a metal molded product is circular, the diameter is defined as the opening width, and if it is rectangular, the long side is defined as the opening width.

[0030] The thickness D of the nozzle plate 10 is defined as the thickness at a point at least 1 mm away from either the positioning hole 11 or the nozzle 12. The thickness D is, for example, 20 to 100 μm. The positioning hole 11 is an example of a "hole" in this disclosure, and the nozzle 12 is an example of a "small hole" in this disclosure.

[0031] Figure 2 is a schematic diagram illustrating the thickness of the positioning hole 11 of the nozzle plate 10 and the periphery of the nozzle 12. Figure 2A is a cross-section end view obtained by cutting along the line IIA-IIA in Figure 1, showing the cross-section of the positioning hole 11. Figure 2B is a cross-section end view obtained by cutting along the line IIB-IIB in Figure 1, showing the cross-section of the nozzle 12.

[0032] In this nozzle plate 10, if the thickness of the periphery of the positioning hole 11 is h1 [μm], the thickness of the periphery of the nozzle 12 is h2 [μm], and the thickness of the main body of the nozzle plate 10 is D [μm], then (h1 - h2) / D < 0.1. In other words, the nozzle plate 10 in this example is characterized by the fact that the difference in the raised thickness at the periphery of the positioning hole 11 from the raised thickness at the periphery of the nozzle 12 is less than 10%.

[0033] In metal molded products made by electroforming, which have multiple holes of different opening widths, a raised portion is formed around the edges of the holes, where the thickness is greater than that of the main body. The larger the opening width of the hole, the thicker the raised portion around the hole tends to be. Conventionally, the difference between the raised portion around the edge of the hole with the largest opening width and the raised portion around the edge of the hole with the smallest opening width was very large. In contrast, by using the electroforming master plate and metal molded product manufacturing method described later, it is possible to obtain a metal molded product in which the difference in thickness around the edges of holes with different opening widths is suppressed, as described above.

[0034] The following describes one embodiment of a method for manufacturing an electroforming master plate and a metal molded product for producing the nozzle plate 10 described above.

[0035] <Electroforming Master Plate> Figure 3 is a plan view showing a part of an electroforming master plate 20 of one embodiment used in the manufacture of a nozzle plate 10. Figure 4 is a cross-sectional end view of the electroforming master plate 20 shown in Figure 3, cut along the IV-IV line. The nozzle plate 10 is an example of a metal molded product.

[0036] The electroforming master plate 20 has an electroforming substrate 30 with insulating masks 21 and 22 on its conductive surface. The electroforming substrate 30 only needs to have conductivity on its surface, but in this case, it comprises a substrate 31 and a metal layer 32 provided on its surface.

[0037] Masks 21 and 22 are provided to form relatively large holes and relatively small holes (in this case, the positioning holes 11 and nozzle 12 of the nozzle plate 10) in the metal molded product, respectively. In this example, masks 21 and 22 are protrusions that extend from the surface of the metal layer 32. The thickness of masks 21 and 22 is, for example, 2 μm.

[0038] The mask 22 is a nozzle mask for forming the nozzle 12. The contour of the mask 22 in plan view is the same as the contour of the nozzle 12 in plan view, and the mask 22 is circular in plan view. The mask 22 is an example of a "small hole mask" of this disclosure. The diameter Am2 of the mask 22 is larger than the diameter A2 of the nozzle 12, for example, 150 μm to 200 μm. In this example, 130 masks 22 in 8 rows are formed in a 100 mm × 40 mm area of ​​the electroforming master plate 20, corresponding to the arrangement pitch and number of nozzles 12 on the nozzle plate 10 described above.

[0039] The mask 21 is a positioning hole mask for forming the positioning hole 11. The mask 21 has a contour in plan view that corresponds to the contour of the positioning hole 11, and is a ring-shaped mask (hereinafter sometimes referred to as the ring-shaped mask 21) having a hole portion 21a on the inside. As shown in Figures 3 and 4, in this example, the ring width of the mask 21 is w and the thickness is d. When the mask 21 and the mask 22 are formed simultaneously, their thicknesses are approximately the same. When used in the manufacture of a metal molded product with a main body thickness D [μm] (see Figure 2), it is preferable that the ring width w [μm] and thickness d [μm] of the mask 21 satisfy w > 2(D - d). It is also preferable that w < 4(D - d).

[0040] The ring width w mentioned above shall be the average value of the ring widths measured at multiple locations. However, it is preferable that the ring width w is approximately uniform.

[0041] Since masks 21 and 22 are insulating, no metal grows on the surfaces of masks 21 and 22, and the parts corresponding to masks 21 and 22 become openings, forming the positioning holes 11 and nozzles 12.

[0042] The electroforming substrate 30 having a conductive surface can be obtained, for example, by using a glass wafer as the substrate 31 and forming a metal layer 32 such as nickel or copper on its surface by sputtering or vacuum evaporation. As the substrate 31, an insulating substrate such as a glass wafer or a semiconductor substrate such as a silicon substrate can be used. Further, a metal substrate may be used as the substrate 31. If it is a metal substrate, there is no need to separately form a metal layer by sputtering or the like.

[0043] The masks 21 and 22 may be made of a non-conductive material. For example, metal oxides or photosensitive resins are used. Examples of the metal oxide include silicon oxide. When a metal oxide is used as the masks 21 and 22, the masks 21 and 22 remain on the substrate side during the peeling process described in the metal molding manufacturing method described later when the metal layer is peeled off. Therefore, the electroforming master can be repeatedly used a plurality of times.

[0044] Here, a method for producing an electroforming master will be described. FIG. 5 is a diagram showing the manufacturing process of the electroforming master 20. In each process diagram of FIG. 5, the end face of the cutting part shown in FIG. 4 is shown. In this example, the case where a photosensitive resin is used as the masks 21 and 22 will be described.

[0045] First, a metal layer 32 is formed on a substrate 31 such as a glass wafer by sputtering (step S1). Next, a photosensitive resin is applied on the metal layer 32 to form a photosensitive resin film 24 (step S2). Then, a mask 26 for pattern formation is arranged facing the photosensitive resin film 24, and the photosensitive resin film 24 is pattern-exposed (step S3). And by developing the exposed photosensitive resin film, an electroforming master 20 provided with the masks 21 and 22 is obtained (step S4).

[0046] <Manufacturing method of metal molded product> Next, a manufacturing method of a nozzle plate 10, which is an example of a metal molded product, using the above electroforming master 20 will be described. The manufacturing method of the metal molded product (here, the nozzle plate 10) includes an electroforming process and a peeling process using the above electroforming master 20. FIG. 6 is a diagram showing the manufacturing process of the metal molded product. In FIG. 6, the state of electroforming on the end face of the cutting part shown in FIG. 4 is schematically shown.

[0047] First, prepare a master disk 20 for electroforming (step S11). Step S11 may include a process of manufacturing the master disk 20 for electroforming.

[0048] Next, in the electroforming step S12, the master disk 20 for electroforming is immersed in an electroforming solution in an electroforming apparatus, and a metal deposited from the electroforming solution is electrodeposited on the surface.

[0049] During electroforming, while an electroformed product 10A grows from the surface of the metal layer 32, no metal is deposited on the surfaces of the insulating masks 21 and 22, and the electroformed product 10A does not grow. The electroformed product 10A gradually grows on the surface of the metal layer 32. When the thickness of the grown electroformed product 10A exceeds the thickness of the masks 21 and 22, the electroformed product 10A grows so as to cover the edges of the masks 21 and 22 from the surface of the previously grown electroformed product 10A. The electroformed product 10A grows from the edges of the masks 21 and 22 toward the center. Also, since the metal layer 32 is exposed in the hole 21a of the ring-shaped mask 21, an electroformed product 10B also grows in the hole 21a. The electroformed products 10A deposited outside the ring-shaped mask 21 and the nozzle mask 22 are connected, but the electroformed product 10B deposited in the hole 21a grows independently of the electroformed product 10A. That is, the electroformed product 10B is separated from the electroformed product 10A by a ring-shaped opening 11a along the ring-shaped mask 21. Also, an opening having the center of the substantially central position of the nozzle mask 22 as the opening center is formed, and this opening corresponds to the nozzle 12. As the thickness of the electroformed product 10A increases, the electroformed product 10A grows toward the center of the masks 21 and 22, so the respective opening widths gradually become smaller. When the electroformed product 10A has grown to a desired thickness, the width Am2 (diameter) of the mask 22 is determined so that the nozzle 12 has a desired opening width A2 (diameter).

[0050] Also, in the electroforming step S12, it is preferable to perform electroforming under the condition that the body thickness D of the electroformed product 10A satisfies w > 2(D - d). In addition, it is more preferable to perform electroforming under the condition that the body thickness D of the electroformed product 10A satisfies w < 4(D - d).

[0051] Furthermore, it is even more preferable to perform electroforming under the condition that the opening width W of the positioning hole 11 formed by the ring-shaped mask 21 of the electroformed product 10A and the thickness D of the main body satisfy W > 4(D - d).

[0052] After the electroforming process, the electroformed product 10A is peeled off from the electroforming master plate 20 (peeling process S13). At this time, the electroformed product 10B that has grown in the holes 21a of the ring-shaped mask 21 remains on the electroforming master plate 20 because it is not connected to the electroformed product 10A. In Figure 6, it is shown that the masks 21 and 22 made of photosensitive resin also remain on the electroforming master plate 20 when the electroformed product 10A is peeled off, but in some cases, parts of the masks 21 and 22 may be peeled off from the electroforming master plate 20 integrally with the electroformed product 10A. The masks 21 and 22 are washed and removed to obtain the nozzle plate 10.

[0053] Since the electroforming master plate 20 of this embodiment is equipped with a ring-shaped mask 21, it is possible to suppress the bulging of the electroformed material around the periphery of the hole even when forming a relatively large opening hole (positioning hole 11 in this example).

[0054] Conventionally, a mask with a shape corresponding to the shape of the positioning hole 11, rather than a ring shape, was used as a mask for the positioning hole 11 (see Figure 7). Figure 7 is a diagram illustrating the growth of the electroformed product 110A when an electroforming master plate 120 equipped with a conventional rectangular mask 121 for the positioning hole 11 is used. In Figure 7, (a) shows the electroforming master plate 120 and the cut end face of the electroformed product 110A during electroforming, and the flow of current during electroforming is schematically shown by arrows in the figure. (b) is a plan view of (a) as seen from the top surface of the electroformed product 110A. (c) shows the cut end face showing the state in which the electroformed product 110A has been separated from the electroforming master plate 120. In plan views such as (b), the masks 121 and 122 are indicated by dots.

[0055] As shown in Figure 7(a), the current concentration at the periphery of small holes with small opening diameters, such as the nozzle 12, is not very large, but the current concentrates at the periphery of large holes with wide openings, such as the positioning hole 11. As a result, metal tends to deposit at the periphery of the positioning hole 11, i.e., at the edge of the rectangular mask 121, causing it to bulge thicker than the main body. For example, if the electroformed material 110A is the nozzle plate, the deposited surface with a bulge at the periphery of this hole is attached to the main body of the recording head. Therefore, if the bulge at the periphery of the positioning hole 11 is large, there is a concern that problems such as inaccurate positioning or easy peeling may occur.

[0056] In contrast, the electroforming master plate 20 of this embodiment is equipped with a ring-shaped mask 21 as a mask for the positioning holes 11. Figure 8 is a diagram illustrating the growth of the electroformed product 10A when equipped with the ring-shaped mask 21. In Figure 8, (a) shows the electroforming master plate 20 and the cut end face of the electroformed product 10A during electroforming, and the flow of current during electroforming is schematically shown by arrows in the figure. (b) is a plan view of (a) as seen from the top surface of the electroformed product 10A. (c) shows the cut end face showing the state in which the electroformed product 10A has been separated from the electroforming master plate 20. Note that in the plan view (b), the mask 21 is shown as a dot for ease of visibility. In Figures 8 and beyond, the mask 21 is also shown as a dot in the plan views.

[0057] As shown in Figure 8(a), when a ring-shaped mask 21 is provided, current flows through the holes in the ring-shaped mask 21, thus suppressing the concentration of current at the periphery of the mask 121, as seen in the case of the rectangular mask 121 shown in Figure 7. Therefore, in the electroformed product 10A, the bulging at the periphery of the positioning holes 11 is suppressed. Compared with the electroformed product 110A shown in Figure 7, the bulging at the periphery of the positioning holes 11 is suppressed, allowing for accurate positioning on the recording head body and suppressing peeling after attachment.

[0058] If the ring width w [μm] and thickness d [μm] of the mask 21 satisfy the relationship w > 2(D - d) with respect to the thickness D [μm] of the main body of the metal molded product, it is possible to suppress the connection between the electroformed material 10B growing in the hole 21a of the mask 21 and the electroformed material 10A that will become the metal molded product. Furthermore, if w < 4(D - d) is satisfied, the effect of suppressing metal bulging around the positioning hole 11 provided in the electroformed material 10A that will become the metal molded product is high.

[0059] Specifically, the ring width w is preferably 450 μm or less, more preferably 300 μm or less, and even more preferably 150 μm or less. These values ​​are particularly preferable when the body thickness of the metal molded product is 30 μm to 80 μm.

[0060] Below, modified examples of the mask for the positioning holes will be described with reference to Figures 9 to 12.

[0061] The positioning hole mask shown in Figure 9 is a stepped ring-shaped mask 41 in which the center of the ring width in the width direction protrudes more from the surface than the ends of the ring width in the width direction. Figure 9(a) is a cross-section end view showing the electroformed product 10A and the electroformed product 10B growing in the holes of the ring-shaped mask 41 when electroforming is performed using an electroforming master plate equipped with the ring-shaped mask 41. Figure 9(b) is a plan view of the ring-shaped mask 41. The ring-shaped mask 41 consists of a first-stage mask 42 having substantially the same shape as the ring-shaped mask 21, and a second-stage mask 43 provided on the first-stage mask 42 in the center of the ring width direction. In this case, it is preferable that the first-stage mask 42 satisfies the same conditions as the ring-shaped mask 21. By providing the second-stage mask 43 in a stepped shape in this way, it is possible to prevent the electroformed product 10B growing in the holes 41a of the ring-shaped mask 41 from connecting with the electroformed product 10A which becomes the metal forming part, even when the thickness of the electroformed product increases.

[0062] The positioning hole mask shown in Figure 10 is a ring-shaped mask 51 in which the ring width is formed to be narrower in one part 51b than in other parts. The ring-shaped mask 51 has a ring width in one part 51b that is narrower than the ring width in other parts. Figure 10(a) is a plan view of the ring-shaped mask 51, and (b) is a plan view of the state in which the electroformed parts 10A and 10B are formed on the ring-shaped mask 51. In Figure 10(b), the gray parts are the electroformed parts.

[0063] When electroforming is performed using an electroforming master plate equipped with a ring-shaped mask 51, as shown in Figure 10(b), in a portion 51b where the ring width of the ring-shaped mask 51 narrows, a connection point 10AB is created between the electroformed product 10A formed on the outside of the ring-shaped mask 51 and the electroformed product 10B formed in the hole 51a. When the electroformed product 10A is peeled off the electroforming master plate while the electroformed product 10A and the electroformed product 10B are slightly connected in this way, the electroformed product 10B can be peeled off together with the electroformed product 10A. By cutting the electroformed product 10B at the connection point 10AB with the electroformed product 10A, a metal molded product made of the electroformed product 10A can be obtained.

[0064] The positioning mask 60 shown in Figure 11 consists of a ring-shaped mask 21 and an internal mask 61 positioned in the hole 21a of the ring-shaped mask 21 at a distance from the ring-shaped mask 21. Figure 11(a) is a plan view of the positioning mask 60, and (b) is a plan view of the positioning mask 60 with the electroformed parts 10A, 10Ba, and 10Bb formed on it. In Figure 11(b), the gray areas are the electroformed parts.

[0065] The ring-shaped mask 21 is the same as the one described in the previous embodiment. In this example, the internal mask 61 is a ring-shaped mask similar in shape to the ring-shaped mask 21. When electroforming is performed using an electroforming master plate equipped with the internal mask 61 in the hole 21a of the ring-shaped mask 21, as shown in Figure 11(b), an electroformed product 10Ba that grows in a ring shape from between the ring-shaped mask 21 and the internal mask 61, and an electroformed product 10Bb that grows in the hole 61a of the internal mask 61 are formed in the hole 21a of the ring-shaped mask 21. When the electroformed product 10A, which will become a metal molded product, is peeled off from the electroforming master plate, the electroformed products 10Ba and 10Bb in the hole 21a of the ring-shaped mask 21 will remain on the electroforming master plate.

[0066] As shown in the peeling process S13 in Figure 6, when a ring-shaped mask 21 without an internal mask 61 is used, the electroformed material 10B formed in the hole 21a remains on the electroforming master plate side during peeling. When reusing this electroforming master plate, it is necessary to remove this electroformed material 10B. A dissolving solution that dissolves electroformed material is used to remove the electroformed material 10B, but the larger the electroformed material 10B, the longer it takes to remove it. In contrast, as shown in Figure 11, by providing an internal mask 61 in the hole 21a of the ring-shaped mask 21, the electroformed material formed in the hole 21a grows in two parts: electroformed material 10Ba and 10Bb. Therefore, electroformed material 10Ba and 10Bb are smaller than the electroformed material 10B formed when the internal mask 61 is not provided. Therefore, by using a positioning mask 60 equipped with an internal mask 61 in the hole 21a of the ring-shaped mask 21, the time required for the electroformed material remaining on the electroforming master plate to dissolve in the melting solution can be shortened compared to a case where the internal mask 61 is not provided.

[0067] Furthermore, when using the mask 60 shown in Figure 11, it is preferable that the opening width A1 of the positioning hole 11 of the metal molded product made of electroformed material 10A satisfies the condition A1 > 4(D-d).

[0068] The positioning mask 70 shown in Figure 12 consists of a ring-shaped mask 21 and an internal mask 71 positioned in the hole 21a of the ring-shaped mask 21 at a distance from the ring-shaped mask 21. Figure 12(a) is a plan view of the positioning mask 70, and (b) is a plan view of the positioning mask 70 with the electroformed parts 10A and 10C formed on it. In Figure 12(b), the gray areas are the electroformed parts.

[0069] The ring-shaped mask 21 is the same as that described in the previous embodiment. The internal mask 71 is a plurality of fine masks, including a plurality of dot-shaped masks 71a that are isolated from each other. When electroforming is performed using an electroforming master plate equipped with an internal mask 71 including dot-shaped masks 71a in the holes 21a of the ring-shaped mask 21, as shown in Figure 12(b), an electroformed product 10C having holes 15 at positions corresponding to the dot-shaped masks 71a grows in the holes 21a of the ring-shaped mask 21. When the electroformed product 10A, which will become a metal molded product, is peeled off from the electroforming master plate, the electroformed product 10C in the holes 21a of the ring-shaped mask 21 will remain on the electroforming master plate.

[0070] As shown in Figure 12(b), the electroformed product 10C formed in the holes 21a of the ring-shaped mask 21 has holes 15 corresponding to the dot-shaped mask 71a, and therefore has a larger surface area compared to the electroformed product 10B formed without the internal mask 71. Therefore, by using a positioning mask 70 equipped with the internal mask 71 in the holes 21a of the ring-shaped mask 21, the area in contact with the molten metal increases compared to the case without the internal mask 71, thus shortening the time it takes for the electroformed product remaining on the electroforming plate to dissolve in the molten metal.

[0071] The internal masks 61 and 71 formed in the holes 21a of the ring-shaped mask 21 are not limited to the ring-shaped or dot-shaped masks described above, but can be any shape as long as they can reduce the size of the electroformed material formed in the holes 21a or increase the surface area of ​​the electroformed material. If the substrate 31 is an electroforming master plate using a silicon master plate and equipped with a mask made of a silicon oxide film, it can be reused after a cleaning process to remove the electroformed material remaining after the peeling process. If the time of this cleaning process can be shortened, productivity can be improved.

[0072] In this embodiment, the nozzle plate 10 was described as an example of a metal molded product, but the metal molded products formed by the electroforming master plate and metal molded product manufacturing method of this disclosure are not limited to the nozzle plate 10. The electroforming master plate and metal molded product manufacturing method of this disclosure are particularly suitable for manufacturing metal molded products having holes with an opening width of 1 mm or more. The opening width of the holes is, for example, 5 mm or less, and more preferably 2 mm or less. Furthermore, for metal molded products having multiple holes with different opening widths, for example, the opening width of the smallest hole is 100 μm or less, and the opening width of the largest hole is 1 mm or more.

[0073] [Verification Test] The results of the verification test regarding the relationship between the mask width of the ring-shaped mask and the amount of electroformation raised at the periphery of the hole formed in the ring-shaped mask will be explained with reference to Figure 13.

[0074] Electroforming master plates (samples 1-3) equipped with masks M1-M4, schematically shown below the graph in Figure 13, were prepared, and electroforming was performed using these master plates to achieve a body thickness of 50 μm. Mask M1 is a circular mask without holes, with a diameter of 1600 μm. Masks M2-M4 all have the same outline diameter as mask M1 (1600 μm), but are ring-shaped with holes in the center. The ring widths of masks M2-M4 were 450 μm, 300 μm, and 150 μm, respectively. In the obtained electroformed products, the amount of protrusion at the periphery of the holes formed corresponding to each mask M1-M4 was measured. Specifically, the thickness of the most protruding part at the periphery of the holes formed corresponding to masks M1-M4 was measured, and the thickness of the body portion (50 μm) was subtracted from that thickness to obtain the amount of protrusion [μm]. The results are shown in the graph in Figure 13. The graph in Figure 13 shows the relationship between the ring width and the amount of raised surface.

[0075] As shown in Figure 13, when the mask was ring-shaped, the bulging was suppressed compared to when it was not ring-shaped. Furthermore, it was found that with ring-shaped masks, the smaller the ring width, the greater the effect of suppressing bulging. By setting the ring width to 450 μm or less, the bulging was suppressed to approximately half that of the case with a non-ring-shaped mask. Moreover, by setting the ring width to 150 μm or less, the bulging could be reduced to 1 μm or less.

[0076] Furthermore, based on the above results, it is considered that a mask having a contour corresponding to the contour of a hole provided in a metal molded product, where the contour is a circle with a diameter exceeding 150 μm or a polygon with a maximum width exceeding 150 μm, can be made ring-shaped with a hole to suppress the bulging around the hole. The effect of making it ring-shaped is considered to be particularly high when using a mask with a maximum width of 1 mm or more (on the order of millimeters).

[0077] Regarding the above embodiments, the following further notes are disclosed. <Note 1> An electroforming master plate for manufacturing a metal molded product having holes, comprising an insulating mask on its surface for forming holes in the metal molded product, wherein the mask includes a ring-shaped mask whose shape, when viewed from above, has a contour corresponding to the contour of the holes and has a hole portion on the inside. <Note 2> An electroforming master plate used to manufacture a metal molded product having a body thickness of D [μm], wherein the ring-shaped mask is a protrusion that protrudes from the surface on which the electroformed metal is electroformed, and the electroforming master plate according to Note 1 satisfies w > 2 (D - d) when the ring width of the protrusion of the ring-shaped mask is w [μm] and the thickness is d [μm]. <Note 3> An electroforming master plate according to Note 2, satisfying w < 4 (D - d). <Note 4> An electroforming master plate according to any one of Notes 1 to 3, wherein the ring width of the ring-shaped mask is 450 μm or less. <Note 5> The electroforming master plate according to any one of Notes 1 to 4, wherein the ring-shaped mask is stepped in shape, with the surface protruding more from the widthwise ends of the ring-shaped mask at the center in the widthwise direction of the ring width. <Note 6> The electroforming master plate according to any one of Notes 1 to 4, wherein the ring width of the ring-shaped mask is formed to be narrower in some parts than in other parts. <Note 7> The electroforming master plate according to any one of Notes 1 to 6, wherein the mask has an internal mask positioned at a distance from the ring-shaped mask in the hole of the ring-shaped mask. <Note 8> The electroforming master plate according to Note 7, wherein the internal mask is similar in shape to the ring-shaped mask. <Note 9> The electroforming master plate according to Note 7, wherein the internal mask includes a plurality of fine masks. <Note 10> An electroforming master plate used to manufacture a metal molded product having a small hole with an opening width smaller than that of the hole, wherein the mask includes a small hole mask having a contour corresponding to the contour of the small hole, which is positioned differently from the ring-shaped mask.<Note 11> A method for manufacturing a metal molded product having holes, comprising: an electroforming step using an electroforming master plate having an insulating mask on its surface for forming holes in the metal molded product, wherein the mask is a ring-shaped mask whose shape in plan view has a contour corresponding to the contour of the holes and has a hole portion on the inside; and a peeling step for peeling the electroformed product formed in the electroforming step from the electroforming master plate. <Note 12> The method for manufacturing a metal molded product according to Note 11, wherein in the electroforming step, the body thickness D [μm] of the electroformed product formed by electroforming is carried out under the condition that w > 2(D - d), where w [μm] is the ring width of the ring-shaped mask and d [μm] is the thickness. <Note 13> The method for manufacturing a metal molded product according to Note 12, wherein in the electroforming step, the electroforming is carried out under the condition that w < 4(D - d). <Note 14> A method for manufacturing a metal molded product according to any one of Notes 11 to 13, wherein in the peeling step, when peeling off the metal molded product, the electroformed material formed in the holes of the ring-shaped mask is left on the electroforming master plate while peeling off the metal molded product. <Note 15> A method for manufacturing a metal molded product according to any one of Notes 11 to 13, wherein in the electroforming step, an electroforming master plate is used in which the ring width of the ring-shaped mask is formed to be narrower in some parts than in other parts, and in the peeling step, when peeling off the metal molded product, the electroformed material formed in the holes of the ring-shaped mask is peeled off together with the metal molded product. <Note 16> A metal molded product made of electroformed material and having a plurality of holes with different opening widths, wherein when the thickness of the periphery of the hole with the largest opening width is h1 [μm], the thickness of the periphery of the hole with the smallest opening width is h2 [μm], and the thickness of the main body is D [μm], the condition (h1 - h2) / D < 0.1 is satisfied.

[0078] The disclosure of Japanese Patent Application No. 2024-164353, filed on September 20, 2024, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually noted to be incorporated by reference.

Claims

1. An electroforming master plate for manufacturing a metal molded product having holes, the master plate having an insulating mask on its surface for forming the holes in the metal molded product, wherein the mask includes a ring-shaped mask whose shape, when viewed from above, has a contour corresponding to the contour of the holes and has a hole portion on the inside.

2. An electroforming master plate used to manufacture a metal molded product having a body thickness of D [μm], wherein the ring-shaped mask is a protrusion that protrudes from the surface on which the electroformed metal is electroformed, and when the ring width of the ring-shaped mask is w [μm] and the thickness is d [μm], the condition w > 2(D - d) is satisfied, according to claim 1.

3. The electroforming master plate according to claim 2, satisfying w < 4(D-d).

4. The electroforming master plate according to claim 1, wherein the ring width of the ring-shaped mask is 450 μm or less.

5. The electroforming master plate according to claim 1, wherein the ring-shaped mask has a stepped shape in which the center portion in the width direction of the ring width of the ring-shaped mask protrudes more from the edges in the width direction of the ring width.

6. The electroforming master plate according to claim 1, wherein the ring width of the ring-shaped mask is formed to be narrower in some parts than in other parts.

7. The electroforming master plate according to claim 1, wherein the mask has an internal mask disposed at a distance from the ring-shaped mask in the hole portion of the ring-shaped mask.

8. The electroforming master plate according to claim 7, wherein the internal mask is similar in shape to the ring-shaped mask.

9. The electroforming master plate according to claim 7, wherein the internal mask includes a plurality of fine masks.

10. The electroforming master plate used to manufacture a metal molded product having a small hole with an opening width smaller than the hole, wherein the mask includes a small hole mask positioned differently from the ring-shaped mask and having a contour corresponding to the contour of the small hole.

11. A method for manufacturing a metal molded product having holes, comprising: an electroforming step using an electroforming master plate having an insulating mask on its surface for forming holes in the metal molded product, wherein the mask includes a ring-shaped mask whose shape in plan view has a contour corresponding to the contour of the holes and has a hole portion on the inside; and a peeling step for peeling the electroformed product formed in the electroforming step from the electroforming master plate.

12. The method for manufacturing a metal molded product according to claim 11, wherein in the electroforming step, the body thickness D [μm] of the electroformed product formed by electroforming is carried out under the condition that w > 2(D - d), where w [μm] is the ring width of the ring-shaped mask and d [μm] is the thickness.

13. The method for manufacturing a metal molded product according to claim 12, wherein the electroforming step is carried out under the condition that w < 4(D-d).

14. The method for manufacturing a metal molded product according to any one of claims 11 to 13, wherein, in the peeling step, when peeling off the metal molded product, the electroformed material formed in the holes of the ring-shaped mask is left on the electroforming master plate while the metal molded product is peeled off.

15. The method for manufacturing a metal molded product according to any one of claims 11 to 13, wherein, in the electroforming step, an electroforming master plate is used in which the ring width of the ring-shaped mask is formed to be narrower in some parts than in other parts, and in the peeling step, when peeling the metal molded product, the electroforming formed in the holes of the ring-shaped mask is peeled off together with the metal molded product.

16. A metal molded product made of electroformed material and having a plurality of holes with different opening widths, wherein when the thickness of the periphery of the hole with the largest opening width is h1 [μm], the thickness of the periphery of the hole with the smallest opening width is h2 [μm], and the thickness of the main body is D [μm], the metal molded product satisfies (h1 - h2) / D < 0.1.

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