Decorated ceramic parts and methods for manufacturing the same
By reversing the material arrangement in decorative watch parts to use an amorphous metal alloy substrate with a ceramic layer, the method addresses the drawbacks of ceramic substrates, offering durability, cost-effectiveness, and the ability to produce complex shapes with superior layer quality and adhesion.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- COMADUR
- Filing Date
- 2025-12-17
- Publication Date
- 2026-07-02
AI Technical Summary
Existing decorative watch parts using ceramic substrates with amorphous metal decoration face issues such as high production costs, complexity, brittleness, and breakage during manufacturing and assembly due to the inherent weaknesses of ceramic materials.
Reversing the material arrangement by using an amorphous metal alloy substrate with a ceramic layer, allowing for the formation of decorations made of either amorphous metal alloy or ceramic, utilizing techniques like microarc oxidation and plasma electrolytic oxidation to deposit or convert the ceramic layer.
This approach provides a durable and cost-effective manufacturing method that achieves the desired aesthetic appearance and surface hardness while avoiding the brittleness of ceramics, enabling mass production of complex shapes with superior layer quality and adhesion.
Smart Images
Figure 2026110551000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an ornament made of two materials, particularly a watch part, having an amorphous metal alloy substrate provided with a ceramic layer on a part of its surface. The present invention also relates to a method used for manufacturing this ornament.
Background Art
[0002] Decorative watch parts combining amorphous metal and ceramic as constituent materials are already available in the prior art. These parts are currently made using a ceramic substrate with an amorphous metal decoration inlaid. One technique consists of engraving a ceramic watch part and then inlaying the amorphous metal.
[0003] Using a ceramic substrate for these watch parts has several drawbacks. First, it takes time and cost to prepare the ceramic substrate. Second, ceramic is a brittle material and not strong against bending. This may lead to breakage during the manufacturing process or when attaching the part to the case.
[0004] Another technique consists of producing a positive amorphous metal index on a ceramic substrate. This is done by galvanically growing copper that functions as a die during the inlay step and then dissolving it using an acid. This method is very complex and expensive, so it is limited to very small-scale production. Furthermore, the vulnerability of the ceramic substrate remains a problem.
Summary of the Invention
Problems to be Solved by the Invention
[0005] An object of the present invention is to improve the above drawbacks by providing a decorative double-material part with the materials in reverse arrangement to avoid the drawbacks associated with handling brittle ceramics and to make the method easier to use.
Means for Solving the Problems
[0006] For this purpose, it is proposed to start with an amorphous metal alloy substrate in which a ceramic layer is provided on a portion of the substrate surface, and decoration is formed with either an amorphous metal alloy or ceramic.
[0007] More specifically, the present invention relates to an ornament comprising a substrate having a surface that defines a first portion having positive and / or negative relief with respect to a surface plane and a second portion extending within the surface plane, wherein the first portion or the second portion forms an ornament, and the ornament is characterized in that the first portion is formed from a substrate made of an amorphous zirconium-based metal alloy and the second portion is formed from a ceramic layer deposited on the substrate, or conversely, the first portion is formed from the ceramic layer deposited on the substrate and the second portion is formed from the substrate made of an amorphous zirconium-based metal alloy.
[0008] Compared to integrated ceramic components, it is possible to achieve the same aesthetic appearance and surface hardness while eliminating the brittle behavior of the material. For example, with a ceramic middle, the horn can easily break upon impact, potentially leading to loss of the ristretto. In the case of amorphous metal with a ceramic layer, the horn will not break upon impact.
[0009] Using amorphous metals as substrates offers many other advantages. Because amorphous metals are defect-free, the current for ceramicization is far more uniform compared to ceramics and conventional metals. In the case of electroplating, the quality of the resulting layer is far superior to that of conventional metal plating. This makes it possible to grow dense layers that are several tens of millimeters thicker than with current methods. Another advantage is that substrates can be produced at a low cost. In fact, machining amorphous metals such as zirconium is far easier and faster than machining ceramics or crystalline zirconium. Furthermore, these materials can be injection molded or stamped during mass production, further reducing manufacturing costs. Compared to crystalline zirconium, amorphous zirconium can be used inexpensively because substrates with reliefs can be produced by direct injection molding or by hot pressing after injection molding. This is not possible with metallic zirconium, which requires 100% machining. However, machining zirconium is very expensive due to its high flammability and the need for expensive tools.
[0010] Furthermore, because the thermal expansion coefficients of amorphous zirconium and ceramics are very similar, thick layers can be grown without the risk of shear delamination. Ceramics, especially ZrO2, exhibit excellent adhesion to amorphous zirconium-based metal alloys and provide superior wear resistance. In addition, corrosion related to the redox potential delta is also very low with the combination of amorphous zirconium and ZrO2.
[0011] The present invention also relates to a method for manufacturing ornaments. More specifically, the present invention relates to the following steps, namely: - A step of preparing a substrate made from a zirconium-based amorphous metal alloy, wherein the substrate has a surface defining a first portion having positive and / or negative relief with respect to a surface plane and a second portion extending within the surface plane, and the first or second portion is designed to form a decoration. - A step of depositing a ceramic layer on at least a portion of the first and second parts, or converting the substrate into a ceramic layer in at least a portion of the first and second parts, The present invention relates to a method for manufacturing an ornament, comprising the steps of: removing an excess from the ceramic layer in a portion thereof to obtain a first portion formed from the substrate and a second portion formed from the ceramic layer deposited on the substrate, or conversely, obtaining a first portion formed from the ceramic layer deposited on the substrate and a second portion formed from the substrate, wherein the first portion or the second portion is formed of ornamentation.
[0012] The range of parts to be manufactured is extremely diverse, and the method according to the present invention enables the production of complex shapes that were not possible when using ceramic as a substrate. These may be not only exterior parts, but also functional parts of a movement that require the mechanical strength of amorphous metal and the hardness of ceramic. [Effects of the Invention]
[0013] Other objects, advantages, and features of the present invention will become more apparent from the following detailed description with reference to the accompanying drawings. [Brief explanation of the drawing]
[0014] [Figure 1] Figures 1(a) to 1(c) schematically illustrate a series of steps in a method for manufacturing an ornament having an amorphous metal alloy decoration flush with the surface, with the amorphous metal alloy decoration bordered by a ceramic layer. [Figure 2] Figures 2(a) to 2(c) schematically illustrate a series of steps in a method for manufacturing an ornament having a ceramic decoration flush with the surface, the ceramic decoration being bordered by an amorphous metal alloy layer. [Figure 3] Figures 3(a) to 3(c) illustrate modified versions of the method in Figure 1, in which positive decoration is applied. [Figure 4]Figures 4(a) to 4(c) illustrate modified versions of the method in Figure 2, in which negative decoration is applied. [Modes for carrying out the invention]
[0015] The present invention relates to a method for manufacturing ornaments and to ornaments themselves. The ornaments are formed from a zirconium-based amorphous metal alloy substrate having ornamentation, the ornament being ceramic or made from the same amorphous metal alloy as the substrate. The ornaments may be exterior parts used in watches, such as the middle, case back, bezel, buttons, wristlet links, flanges, dial, hands, dial indices, oscillating mass, etc., or movement parts, such as plates, bars, or balance wheels. The present invention is illustrated below with respect to a bezel 5. The amorphous zirconium-based metal alloy can be any alloy such as LM1b, LM1b-X, Vit106a, etc. The ceramic can be an oxide, nitride, or carbide. Preferably, the ceramic is zirconium oxide (ZrO2).
[0016] This method allows for the formation of a decoration 4 flush with the surface, which can be positive as illustrated in Figure 3, as illustrated in Figures 1 and 2, or negative as illustrated in Figure 4. Positive and negative decorations can also be formed on the ornament. The decoration 4 can be made from an amorphous metal alloy 1 integrated with the substrate, as illustrated in Figures 1 and 3, or from a ceramic 3, as illustrated in Figures 2 and 4. The surface 1a of the substrate 1 has at least one decoration 4 made of the amorphous metal alloy 1 or ceramic 3. In the case of a decoration 4 made from the amorphous metal alloy 1, the decoration 4 is surrounded by a ceramic layer 3. It should be noted that the sides of the decoration 4 can be made of ceramic 3, as illustrated in the example in Figure 3. In the case of a decoration 4 made of ceramic 3, the decoration 4 is surrounded by the amorphous metal alloy substrate 1.
[0017] According to the present invention, ceramicization is carried out by depositing a ceramic layer (oxide, carbide, or nitride) or by converting an amorphous zirconium-based metal alloy into a layer of zirconium oxide. This conversion is carried out using microarc oxidation (MAO) or plasma electrolytic oxidation (PEO) techniques. In these techniques, the thickness of the oxide layer is typically about 15–20 μm. The ceramic layer can be deposited with a thickness of about 10–15 nm by electron beam deposition and atomic layer deposition (ALD), or with a thicker layer of about 0.10–0.20 mm by plasma spraying.
[0018] A method for manufacturing a component having ornaments 4 is as follows: In the first step (a) shown in Figures 1(a), 2(a), 3(a), and 4(a), a substrate 1 made from an amorphous zirconium-based metal alloy is prepared. Preferably, the substrate is manufactured by injection molding, with or without decorative reliefs. This injection molding method allows for controlled rapid cooling and ensures the absence of microcrystals in the material. If reliefs are not produced during the injection molding process, the substrate can be hot-pressed into a die of the desired shape, or the reliefs can be formed by conventional milling or grinding.
[0019] In the illustrated examples, the substrate is an ébauche of a bezel with an index to be decorated. This substrate 1 has a relief 2 on its surface 1a. In the modifications shown in Figures 1, 2, and 4, the relief 2 is formed by a recess cut into the substrate. In other words, the relief 2 is negative with respect to the plane of the substrate surface 1a. In the modification shown in Figure 3, the relief 2 forms a structure that covers the plane of the substrate surface 1a. In other words, the relief 2 is positive with respect to the plane of the substrate surface 1a.
[0020] In the second step (b), the ceramic layer 3 is deposited or formed by conversion on the whole or part of the surface 1a and optionally on the side surface of the substrate. During the ceramization process, specific regions on the surface can be masked and only the desired regions can be ceramized. Depending on the thickness of the layer to be deposited or converted, the whole or part of the recess can be filled, and if there are structures on the plane of the surface, the structures are also covered.
[0021] In the third step (c), for example, the excess ceramic 3 is removed by machining, and the substrate 1 for the amorphous metal alloy decoration 4 or the ceramic decoration is exposed on the surface 1a at the height of the decoration 4 or adjacent to the decoration 4. Optionally, the excess amorphous metal alloy can also be removed.
[0022] Thereby, the index for forming the decoration 4 produces a decoration made of the ceramic 3 or the amorphous metal alloy 1, particularly a bezel 5.
Explanation of reference numerals
[0023] 1 Amorphous metal alloy substrate 1a Surface 2 Relief 3 Ceramic layer 4 Amorphous metal alloy decoration, ornament 5 Bezel
Claims
1. An ornament comprising a substrate (1) having a surface (1a) that defines a first portion having positive and / or negative relief (2) with respect to the plane of the surface (1a) and a second portion extending in the plane of the surface (1a), wherein the first portion or the second portion forms a decoration (4), and the ornament is characterized in that the first portion is formed from the substrate (1) made of an amorphous zirconium-based metal alloy and the second portion is formed from a ceramic layer (3) deposited on the substrate (1), or conversely, the first portion is formed from the ceramic layer (3) deposited on the substrate (1) and the second portion is formed from the substrate (1) made of the amorphous zirconium-based metal alloy.
2. The decorative article according to claim 1, characterized in that the ceramic layer (3) is a layer of zirconium oxide.
3. The decorative article according to claim 1, characterized in that the decoration (4) is flush with the plane of the surface (1a), positive with respect to the plane of the surface (1a), or negative with respect to the plane of the surface (1a).
4. The decorative item according to claim 1, characterized in that it is a watch component.
5. An ornament according to any one of claims 1 to 4, characterized in that it is a bezel (5) or a dial.
6. A method for manufacturing ornaments, comprising the following steps: - A step of preparing a substrate (1) made from a zirconium-based amorphous metal alloy, wherein the substrate (1) comprises a surface (1a) defining a first portion having positive and / or negative relief (2) with respect to the plane of the surface (1a) and a second portion extending in the plane of the surface (1a), and the first portion or the second portion is designed to form a decoration (4), - A step of depositing a ceramic layer (3) on at least a portion of the first portion and the second portion, or converting the substrate (1) into a ceramic layer (3) in at least a portion of the first portion and the second portion, A method comprising the steps of: removing an excess from the ceramic layer (3) in a part thereof to obtain the first portion formed from the substrate (1) and the second portion formed from the ceramic layer (3) deposited on the substrate (1); or conversely, obtaining the first portion formed from the ceramic layer (3) deposited on the substrate (1) and the second portion formed from the substrate (1), wherein the first portion or the second portion forms the decoration (4).
7. The method according to claim 6, characterized in that the ceramic layer (3) is a layer of zirconium oxide.