JP5700924B2 - Electroformed body, manufacturing method thereof, and watch part - Google Patents

Description

The present invention relates to an electroformed body by an electroplating method, a manufacturing method thereof , and a timepiece component, and more particularly to a method for manufacturing an electroformed body having a concave portion pattern on a surface portion and a surface form of a surface other than the concave portion and the concave portion.

  According to the electroforming method, it is possible to manufacture a member having very high transferability by using a member called an electromold that is precisely processed. In particular, in recent years, it has been proposed to manufacture electroforms by the LIGA (Lithographie Galvanofomung Abformung) method, which uses a photosensitive material to process the electroform using a silicon process, and to produce parts and molds with micro shapes. (For example, refer to Patent Document 1). In such an electroforming mold, an electroformed body having a high accuracy can be produced from a minute part, and therefore, it is applied to a minute part such as a mechanical wristwatch move part having a complicated shape.

  In recent years, mechanical watches have been designed not only for so-called exterior parts such as watch cases and dials, but also by providing a transparent back or dial so that the inside of the case can be seen. That is, the movement is structured to be visible from the outside.

  For this reason, it is desired that the gears constituting the movement, the receiving parts, the rotating weights provided in the self-winding wristwatch and the like have a decorative property.

  From the same point of view, it is widely desired to improve the decorativeness, the recognizability of parts, and the visibility not only in mechanical wristwatches but also in fine parts and precision parts.

Japanese Patent Laid-Open No. 11-15126

  The present invention has been made in view of the above circumstances, and has a recess in a part of at least one surface of an electroformed body produced by the LIGA method, and the recess has an arbitrary design such as a character and a picture pattern. Another object of the present invention is to provide a method for producing an electroformed body which is formed as a pattern having decorativeness and visibility, and in which the surface form of the surface of the recess is different from the surface other than the recess.

  The present invention employs the following means in order to solve the above problems.

  The method for producing an electroformed body according to the present invention includes a step of forming a metal layer by pattern plating on the surface of a substrate having conductivity on at least a surface, a step of forming an electroforming mold on the surface, and the electroforming mold A step of forming an electroformed part having a composition different from that of the metal layer, a step of removing the substrate and the electroforming mold, and a step of removing the metal layer.

  This electroformed body manufacturing method consists of precise plating resist layer formation by photolithography using a photoresist, and pattern formation such as characters and pattern patterns made of metal layers by thin film fine pattern formation technology by additive method consisting of plating method Next, an electroforming mold that gives the desired electroformed body shape is formed with a thick film photoresist, and electroforming is performed on the metal film pattern and in the electroforming mold, and the electroformed body is separated from the substrate. By removing the metal layer, it is possible to provide an electroformed body having a concave portion with a fine pattern on one surface.

  The method for producing an electroformed body according to the present invention includes a step of forming a metal layer on a conductive surface of a substrate by pattern plating, a step of forming an electroforming mold on the surface, and an interior of the electroforming mold. Forming an electroformed part having a composition different from that of the metal layer on the surface and the upper surface of the metal layer, removing the substrate and the electroforming mold, and removing the metal layer. It is characterized by providing. Moreover, the surface form of the said surface and the surface form of the surface which contact | connects the said electroformed part of the said metal layer differ, It is characterized by the above-mentioned.

  This electroformed body manufacturing method has a surface form different from the surface form of the substrate by a precise plating resist layer formation by photolithography using a photoresist and a thin film fine pattern forming technique by an additive method consisting of a plating method. A pattern such as letters and patterns made of a metal layer is formed. Next, an electroforming mold that gives a desired electroformed body shape is formed by a thick film photoresist, and an electric mold is formed on the metal film pattern and in the electroforming mold. Casting, separating the electroformed body from the substrate, and then removing the metal layer, so that there is a concave portion of a fine pattern on one surface, and the shape of the concave surface and the surface shape on the other surface That is, it is possible to provide electroformed bodies having different surface roughness.

  Such an electroformed body and its manufacturing method have a high masking accuracy and an easy and uniform surface form compared to means such as honing after masking, which is a typical means for modifying a partial surface form. Can be changed.

  According to the present invention, it is possible to provide an electroformed body having a concavo-convex pattern which is visually excellent such as decoration and visibility on at least one surface, and which is excellent in fineness and accuracy.

It is a figure which shows the electroformed body which concerns on embodiment of this invention. It is explanatory drawing which shows the manufacturing method of the electrocast body which concerns on embodiment of this invention. It is explanatory drawing which shows the manufacturing method of the electrocast body which concerns on embodiment of this invention.

  Embodiments according to the present invention will be described with reference to FIGS. 1 to 3. Fig.1 (a) is a figure which shows one surface of the electroformed gearwheel which is the electrocast body of the 1st Embodiment of this invention, FIG.1 (b) is a cross section in AA 'in Fig.1 (a). FIG.

  As shown in FIG. 1, an electroformed gear 101 that is an electroformed body according to this embodiment includes a shaft hole 102 and a gear opening 103 provided to reduce the weight of the gear. Further, among the portions constituting one surface of the electroformed gear 101 that is an electroformed body, the tooth tip surface portion 104, the surface portion of the opening edge portion 105, and the surface portion of the character pattern portion 106 are mirror surfaces. Further, the recess 107 has a satin surface. The electroformed body can be formed of, for example, gold, nickel, iron, or an alloy thereof. That is, the tooth top surface portion 104, the surface of the opening edge portion 105, and the surface of the character pattern portion 106 are different in surface form from the surface of the recess 105. That is, the surface form of the tooth tip surface part 104, the surface of the opening edge part 105, and the surface of the character pattern part 106 may be different from the surface form of the recess 105.

  As shown in FIG. 2, the method for manufacturing the electroformed body includes a step of forming a metal layer having an arbitrary pattern on a conductive substrate on at least one surface, and a step of forming the electroforming mold shown in FIG. And forming the electroformed body in the electroforming mold, separating the electroformed body from the substrate and the mold and making them independent, and removing the metal layer.

  In the step of forming the metal layer, first, as shown in FIG. 2 (a), two layers of chromium and copper (not shown) are formed on the substrate 109 made of a single crystal silicon wafer having a mirror surface from the substrate 109 side. A conductive layer 110 is formed. Further, as shown in FIG. 2B, a positive photoresist is applied to the surface of the conductive layer 110 of the substrate 109, and exposure and development are sequentially performed to obtain a thickness having a desired opening pattern such as characters and picture patterns. A 10 μm first resist layer 111 is formed. Note that the conductive layer 110 may be a single layer of chromium or copper. The first resist layer 111 may be a negative photoresist.

  Next, as shown in FIG. 2 (c), a metal layer 112 is formed by applying copper plating with a thickness of 7 μm, which has a matte surface state, to the opening of the first resist layer 111 by electroplating. To do. Next, as shown in FIG. 2D, the first resist layer 111 is stripped and removed with a stripper such as an alkaline aqueous solution or an organic solvent such as acetone. Note that the thicknesses of the first resist layer 111 and the metal layer 112 are not limited to the thicknesses described above, and the metal layer 112 may be thicker than the first resist layer 111.

  In the step of forming the electroforming mold of FIG. 3 (a) and the step of forming the electroformed body and separating the electroformed body, a chemically amplified epoxy thick film photoresist is applied, and after curing is accelerated by exposure and heating, The electroforming mold 113 is formed by performing development. The thickness of the electroforming mold 113 is about 50 μm to 1 mm in the mechanical wristwatch gear.

  Next, as shown in FIG. 3B, nickel electroforming is performed on the opening of the electroforming mold 113 to form the electroforming portion 114. Moreover, the thickness and surface form of the electroformed part 114 are adjusted by polishing or the like as necessary. Further, as shown in FIG. 3C, the electroformed product 115 is obtained by removing the substrate 109, the conductive layer 111, and the electroforming mold 113. Finally, as shown in FIG. 3 (d), the metal layer 112 made of copper is removed from the electroformed product 115 by etching to obtain an electroformed body 117.

  The electroformed body 117 manufactured in this way becomes a mirror surface portion 118 at a portion in contact with the conductive layer 110 on the substrate 109, and a concave portion 116 whose surface form is a matte state at a portion in contact with the metal layer 112. In addition to the irregularities on the surface, the surface formed between the two has a large contrast, and the pattern formed as the concave portion 118 is more emphasized. It will have.

  2 and 3, the metal layer 112 is formed only inside the opening of the electroforming mold 113, but is not limited to the inside, and there is a portion where the metal layer 112 and the electroforming mold 113 overlap. However, the present embodiment is not limited at all.

  In this embodiment, a copper plating layer is used for the metal layer 112, and nickel electroforming is used for the electroformed portion 108. However, these are not limited, and any material that can be plated can be freely used. You can choose.

  The electroformed body of the present invention can form timepiece parts such as rotating weights, gears, escape wheels, ankles, and balances. Further, not only watch parts but also fine parts and precision parts can be formed.

DESCRIPTION OF SYMBOLS 101 Electroformed gear 102 Shaft hole 103 Gear opening part 104 Tooth tip surface part 105 Opening part edge part 106 Character pattern part 107 Recessed part 108 Electroformed part 109 Substrate 110 Conductive layer 111 1st resist layer 112 Metal layer 113 Electroforming mold 114 Electricity Casting part 115 Electroformed product 116 Recessed surface part 117 Electroformed body 118 Mirror surface part

Claims (4)

An electroformed body comprising an electroformed part having a recess,
The surface roughness of the surface having the concave portion of the electroformed portion and the bottom surface of the concave portion is different ,
The electroformed body, wherein a bottom surface of the concave portion of the electroformed portion is in a satin state . The electroformed body according to claim 1 , wherein a surface of the electroformed portion having the concave portion is in a mirror state. Timepiece components, characterized in that it consists of electroformed body according to any one of claims 1-2. Forming a metal layer by pattern plating on the conductive surface of the substrate;
Forming an electroforming mold on the surface;
Forming an electroformed part having a composition different from that of the metal layer on the surface of the electroforming mold and the upper surface of the metal layer;
Removing the substrate and the electroform;
Removing the metal layer;
With
The method for producing an electroformed body, wherein the surface and the surface of the metal layer in contact with the electroformed portion are formed to have different surface roughness.

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