Method for creating lettering blocks on a dial

Abstract

This invention relates to a method for manufacturing lettering blocks on a watch dial.

Description

Technical Field

[0001] This invention relates to a method for manufacturing lettering blocks on a watch dial. Technical Background

[0002] The purpose of this invention is to improve the method of depositing decorative patterns on the surface of watch components.

[0003] Watch dials typically include lettering to decorate them. For example, these letterings can indicate the hour ring, making it easier to determine the time relative to the position of the watch hands. These letterings can also be used simply to enhance the aesthetic appeal of the dial.

[0004] Typically, these lettering blocks are mounted on the dial through successive joining and optional masking and / or stamping steps. In addition to the cost of the lettering blocks themselves, this results in additional manufacturing costs due to the required positioning accuracy, with the additional manufacturing costs increasing as the lettering blocks become thicker. Summary of the Invention

[0005] This invention relates to a method for manufacturing lettering blocks on a watch dial, characterized in that the method comprises the following steps:

[0006] a) Provide a dial having a front and a back;

[0007] b) Perform surface preparation treatment on the front side;

[0008] c) Deposit a first protective layer at various locations on the dial where at least one decorative layer is provided;

[0009] d) Machining at least one groove in the first protective layer and the decorative layer to form a mold for future inlay blocks, and drilling holes in the dial to form at least one attachment point;

[0010] e) To form lettering blocks by filling the at least one groove with material through electroplating on the dial;

[0011] f) Remove the first protective layer;

[0012] g) Deposit a second protective layer on the front of the dial to cover the dial and the lettering blocks;

[0013] h) Cut the dial to the required size and polish the second protective layer and lettering blocks to the predetermined height;

[0014] i) Selective surface treatment of the ends of the letter blocks;

[0015] j) Remove the second protective layer.

[0016] Other advantageous alternative embodiments according to the invention:

[0017] -The dial is made of a material selected from copper alloy, iron alloy, gold alloy or silver alloy;

[0018] - The decorative layer is made of a material selected from silver, gold, copper, nickel, rhodium or ruthenium;

[0019] - The first protective layer and the second protective layer are based on resin;

[0020] -The resin is selected from acrylic resins, nitrocellulose resins, alkyd resins, or polyurethane resins;

[0021] - The material filling the at least one groove is selected from silver, gold, copper, nickel, rhodium or ruthenium;

[0022] - Remove the first and second protective layers by solvent or plasma;

[0023] - The at least one groove is etched by a laser etching method, which allows the metal layer and the first protective layer to be etched;

[0024] - In step b), the surface preparation of the face includes polishing, pumice polishing and / or dry or wet sanding of the front of the dial;

[0025] - In step b), the surface treatment of the front side is shot peening, sunbursting, mechanical engraving, etching, milling, snail polishing, circular granulation, or any other operation used to obtain a decorative pattern. Attached Figure Description

[0026] Figures 1 to 10 illustrate the sequential steps of a preferred example of the decoration method according to the present invention. Detailed Implementation

[0027] Referring to Figures 1 to 10 will provide a better understanding of the method according to the invention. In the first step a) shown in Figure 1, the method according to the invention includes providing a dial 1 comprising a front side 10 and a back side 11, the front side being intended to accommodate lettering blocks.

[0028] Preferably, and according to the invention, the dial is made of a material selected from copper alloys, iron alloys, gold alloys or silver alloys.

[0029] Of course, as an alternative to using a dial made of conductive material, a dial made of any material coated with a conductive layer can also be used. For example, a ceramic dial coated with silver can be envisioned.

[0030] As shown in Figure 2, the second step b) of the method includes first performing a surface preparation process on the front 10, then selectively patterning the front 10 to locally change its surface condition, and finally depositing at least one decorative layer 2 on it over the entire dial.

[0031] The surface preparation of the front 10 includes polishing, pumice polishing, and / or dry or wet sanding of the dial front. Plasma or laser treatment is also possible.

[0032] Patterning the front of the dial is a standard watch decoration operation. Therefore, patterning is performed through shot peening, sunburst treatment, mechanical engraving, etching, milling, snail polishing, circular granulation, or any other operation used to create or allow for the formation of a decorative pattern. This step aims to decorate the dial and increase adhesion to the dial surface to deposit a decorative layer.

[0033] Decorative layer 2 is made of a material selected from silver, gold, copper, nickel, rhodium, ruthenium, or any other material that can be coated by wet (chemical or electrolytic deposition) or dry (sputtering, PVD) methods.

[0034] Optionally, to improve the mechanical stability of the interface between the decorative layer 2 and the dial 1, an intermediate adhesion layer can be advantageously deposited between the decorative layer 2 and the dial 1. For example, titanium typically has sufficient adhesion on most typical substrates. This layer can be extremely thin: a few nanometers is usually sufficient to significantly improve adhesion.

[0035] The metallic layer deposited on the dial surface has good adhesion properties, promoting the adhesion of the formed lettering. The material used to make this layer can be titanium, nickel, gold, or other materials and / or a combination of multiple layers.

[0036] Preferably, the decorative layer is formed by physical vapor deposition (PVD); however, other types of deposition are also possible, such as electroplating, chemical vapor deposition (CVD), or atomic layer deposition (ALD).

[0037] like Figure 3 As shown, the third step c) of the method involves covering the entire dial with a polymer layer 3 by spraying, dipping, or spin coating, and then curing the resin 3 by heat or UV radiation. Of course, the thickness of this layer will depend on the desired size of the lettering; preferably, the thickness of the layer is 0.02 mm to 0.40 mm.

[0038] Resin 3 is selected from acrylic resins, nitrocellulose resins, alkyd resins, or polyurethane resins.

[0039] Alternatively, the dial 1 can be completely covered with resin 3 and then cured, and the top of the resin layer can be machined to make its upper part completely flat.

[0040] As shown in Figure 4, the fourth step d) of the method includes machining at least one groove 4 in the protective layer and the decorative layer to form a mold for future lettering blocks. In this step, holes are also drilled at multiple locations on the dial to form at least one attachment point 5 for electroplating growth in the next step.

[0041] Advantageously, at least one groove 4 is formed by laser method or by photolithography using positive or negative photoresist, so as to easily control the geometry of the future inlay blocks, so that the groove 4 has walls that are substantially perpendicular to the surface of the dial 1, to quickly etch multiple parts, and ultimately to finely control the surface condition of the etched area.

[0042] As shown in Figure 5, the fifth step e) of the method includes depositing material on the front side 10 of the conductive dial 1 by electroplating to form at least one letter block 6 in a single step. The dial 1 is immersed in the electroplating bath via at least one attachment point 5, which also allows the dial 1 to be used as a cathode.

[0043] The material used to fill at least one groove 4 and form the lettering block 6 on the dial 1 is selected from silver, gold, copper, nickel, rhodium or ruthenium.

[0044] The material used to form the inlay block 6 can be different from the material used for the decorative layer, depending on the desired aesthetic effect.

[0045] As shown in Figure 6, the sixth step f) of the method includes detaching the dial 1 from the first resin layer 3 by dissolving, rinsing, or using plasma. Preferably, an organic solvent suitable for the deposited resin is used to remove the first protective layer.

[0046] like Figure 7 As shown, the seventh step g) of the method includes covering the front surface 10 of the dial 1 with a second protective resin layer 7 by spraying, and then curing the resin 7 by heating or UV radiation. The thickness of the second resin layer is at least equal to the height of the lettering block 6 formed in step e), and preferably greater than the height of the lettering block 6.

[0047] The resin 7 that forms the second protective layer is selected from acrylic resins, nitrocellulose resins, alkyd resins, or polyurethane resins.

[0048] like Figure 8 As shown, the eighth step (h) of the method includes first machining the dial 1 to the required size and shape, and then polishing the protective resin layer 7 and the lettering block 6 to a predetermined height.

[0049] like Figure 9 As shown, the ninth step i) of the method includes selective surface treatment on the top of the letter block 6.

[0050] Selective surface treatments include depositing metal layers through physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or wet methods (electroplating).

[0051] like Figure 10 As shown, the tenth and final step j) of the method includes removing the second protective layer and releasing the dial 1 and its lettering block 6.

[0052] Feet can be soldered to the dial at different steps of the process to facilitate component handling and / or meet product specifications. These feet can serve as contact points to create coating 2 or to form lettering blocks 6 by electroforming. In the latter case, these feet are used instead of holes 5.

[0053] Therefore, it can be understood that the method according to the invention advantageously allows the advantages of machining, photolithography and electroplating to be applied to electroforming in a single electroplating step, to apply lettering blocks on the dial with very high structural precision.

[0054] It goes without saying that the present invention is not limited to the examples shown, but can be made in various alternatives and modifications that are obvious to those skilled in the art.

[0055] Furthermore, the preferred or alternative embodiments of the method according to the invention are provided only as exemplary embodiments of the invention and are not intended to limit it. Therefore, other methods for removing or patterning other materials may be considered.

Claims

1. A method for manufacturing lettering blocks (6) on the dial (1) of a clock, characterized in that, The method includes the following steps: a) Provide a dial (1) having a front (10) and a back (11); b) Perform a surface preparation process on the front side (10), then selectively structure the front side and deposit at least one decorative layer (2) thereon; c) Deposit a first protective layer (3) at various locations on the dial where at least one decorative layer is provided; d) Machining at least one groove (4) in the first protective layer (3) and the decorative layer (2) to form a mold for future inlay blocks, and drilling holes in the dial (1) to form at least one attachment point (5); e) Forming lettering blocks (6) by electroplating a material into the at least one groove (4) on the dial (1); f) Remove the first protective layer (3); g) Deposit a second protective layer (7) on the front (10) of the dial (1) to cover the front of the dial and the lettering block (6); h) Cut the dial (1) to the required size and polish the second protective layer (7) and the lettering block (6) to the predetermined height; i) Perform selective surface treatment on the ends of the inlaid block (6); j) Remove the second protective layer (7).

2. The method according to claim 1, wherein, The dial (1) is made of a material selected from copper alloy, iron alloy, gold alloy or silver alloy.

3. The method according to claim 1 or 2, wherein, The decorative layer (2) is made of a material selected from silver, gold, copper, nickel, rhodium or ruthenium.

4. The method according to claim 1 or 2, wherein, The first protective layer and the second protective layer are resin-based.

5. The method according to claim 4, wherein the resin is selected from acrylic resins, nitrocellulose resins, alkyd resins, or polyurethane resins.

6. The method according to claim 1 or 2, wherein, The material filling the at least one groove is selected from silver, gold, copper, nickel, rhodium, or ruthenium.

7. The method according to claim 1 or 2, wherein, The decorative layer (2) includes the attachment layer.

8. The method according to claim 7, wherein, The adhesion layer contains titanium.

9. The method according to claim 1 or 2, wherein, The first and second protective layers are removed by solvent.

10. The method according to claim 1 or 2, wherein, The at least one groove (4) is etched by a laser etching method, which allows the decorative layer (2) and the first protective layer to be etched.

11. The method according to claim 1 or 2, wherein, In step b), the surface preparation of the face includes polishing, pumice polishing, and / or sanding the front of the dial.

12. The method according to claim 1 or 2, wherein, In step b), the surface treatment of the front side is shot peening, sunlight exposure, mechanical engraving, etching, milling, spiral polishing, or circular granulation.

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