Exterior parts having an interference layer coating deposited on a surface made of a material containing at least 50% by mass of aluminum.
A thin film dielectric coating with Al2O3 and TiO2 layers deposited via ALD on aluminum substrates addresses adhesion and time issues in coloring, achieving rapid, durable, and precise coloration for watches and jewelry.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- THE SWATCH GRP RES & DEVELONMENT LTD
- Filing Date
- 2025-11-12
- Publication Date
- 2026-07-02
AI Technical Summary
Existing methods for coloring exterior parts in watches and jewelry, particularly those with aluminum substrates, face adhesion issues and are time-consuming due to processes like anodization, which increases the risk of damage and requires handling between steps.
A thin film dielectric coating comprising at least two layers, including a base layer of Al2O3 and a termination layer of TiO2, is deposited using Atomic Layer Deposition (ALD) on a substrate containing at least 50% aluminum, ensuring excellent adhesion and enabling quick, precise coloration without handling between layers.
The method provides robust and reproducible coloration with precise interference colors, protecting the substrate from environmental factors while minimizing handling and cycle time, thus overcoming the limitations of anodization.
Smart Images
Figure 2026110506000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of watches, jewelry or fine jewelry, and more particularly to exterior parts used in watches, jewelry or fine jewelry.
[0002] In this specification, the term "exterior part" refers to a part that is visible to the user and has a decorative function, that is, a part that contributes to the visual appearance of the object, as generally understood in the above-mentioned fields.
Background Art
[0003] In the field of watches, jewelry or fine jewelry, market players are constantly seeking new decorative solutions to change the appearance of products in order to enhance the attractiveness of the products or to stand out from competing companies.
[0004] For example, particularly in the field of watch manufacturing, it is common to color exterior parts by depositing a thin layer on a substrate using a vacuum deposition method such as physical vapor deposition or chemical vapor deposition. However, depending on the nature of the substrate and the deposited layer, adhesion problems may occur. This drawback makes the coloring method of the part more complicated because it requires the deposition of an adhesion layer.
[0005] Regarding exterior parts provided with an aluminum substrate, the above-mentioned drawbacks can be improved by using a method of anodizing the substrate to color the exterior parts. However, anodization is a relatively long process because it requires a long cycle time to grow an oxide layer on the substrate and involves a number of steps. Also, since the exterior parts need to be handled between each step, the risk of damaging the exterior parts increases.
Summary of the Invention
Means for Solving the Problems
[0006] The present invention improves upon the above-mentioned drawbacks and relates to an exterior component used in watches, jewelry, or fine jewelry, comprising a substrate having a support surface made of a material containing at least 50% by mass of aluminum, wherein a thin film dielectric coating is deposited on the support surface, comprising at least two layers including a base layer made of Al2O3 and a termination layer made of TiO2 that overlaps the support surface.
[0007] Advantageously, this invention ensures excellent adhesion between the support surface and the thin-film dielectric coating due to the chemical affinity between the support surface and the base layer. Furthermore, by using lamination, vivid and accurate colors can be imparted to exterior components.
[0008] Furthermore, the present invention is an advantageous alternative to coloring aluminum substrates by anodizing, without the drawbacks associated with the process. In fact, the thin film dielectric coating layers are deposited using a method of depositing thin atomic layers, known to those skilled in the art by the acronym "ALD," which stands for "Atomic Layer Deposition," and this method makes it possible to color aluminum substrates quickly and easily without the need to handle exterior components between the deposition of each layer.
[0009] In some specific embodiments, the present invention may further include, individually or in any technically possible combination, one or more of the following features:
[0010] In some specific embodiments, the exterior component comprises an even number of intermediate layers, at least two of which are deposited between a base layer and a terminal layer, and are alternately made of TiO2 and Al2O3 such that the intermediate layer overlapping the base layer is made of TiO2 and the layer in contact with the terminal layer is made of Al2O3.
[0011] In some specific embodiments, the substrate is formed by a body made of pure aluminum or an aluminum alloy, the body having a support surface.
[0012] In some specific embodiments, the substrate comprises a body having a coating made of aluminum nitride, aluminum carbide, aluminum oxide, or aluminum carbonitride, the coating having a support surface.
[0013] In some specific embodiments, the thin-film dielectric coating comprises four intermediate layers.
[0014] In some specific embodiments, the thin film dielectric coating layer has a thickness selected to impart interference colors to the exterior component in CIELAB space in the reflection mode of a standard light source D65, with an observer of 10° and a measured geometry of di:8°, characterized by the parameters L*=[75;85], a*=[-45;-35], b*=[5;15].
[0015] In some specific embodiments, the base layer has a thickness of 1 nm to 10 nm, the intermediate layer has a thickness of 20 nm to 90 nm, and the terminal layer has a thickness of 55 nm to 65 nm.
[0016] In some specific embodiments, the intermediate layers have thicknesses of 25 nm to 30 nm, 75 nm to 85 nm, 15 nm to 25 nm, and 15 nm to 25 nm, respectively, from the intermediate layer closest to the base layer to the intermediate layer closest to the terminal layer. [Brief explanation of the drawing]
[0017] Other features and advantages of the present invention will become apparent from the following detailed description, which is given as a non-limiting example with reference to the figures. [Figure 1] A schematic cross-sectional view of an exterior component according to a preferred exemplary embodiment of the present invention is shown.
[0018] It should be noted that the diagram is not drawn to scale for clarity. [Modes for carrying out the invention]
[0019] The present invention relates to an exterior component 10 used in watches, jewelry, or fine jewelry, the exterior component 10 comprising a substrate 100 having a support surface 101 made of a material containing at least 50% by mass of aluminum.
[0020] The exterior component 10 according to the present invention is schematically shown in Figure 1 and is particularly suitable for forming a watch face or any other component of a watch, preferably an applicator or an internal component such as a hand.
[0021] In this specification, the substrate material may be pure aluminum, aluminum alloy, aluminum nitride, aluminum carbide, aluminum oxide, etc.
[0022] In an exemplary embodiment of the present invention, the substrate 100 is formed by a body made of a material containing at least 50% by mass of aluminum. Thus, the support surface 101 is formed by one side of the body.
[0023] In another exemplary embodiment of the present invention, the substrate 100 may comprise a body having a coating formed thereon that contains at least 50% by mass of aluminum. Thus, the support surface 101 is formed by the surface of the coating.
[0024] Naturally, the type of material containing at least 50% by mass of aluminum determines whether the support surface 101 is formed by the body or by a coating. For example, if the material is pure aluminum or an aluminum alloy, the material can constitute the body of the substrate 100. If the material is aluminum nitride, aluminum carbide, or aluminum carbonitride, the material can constitute a coating deposited by a suitable deposition method such as physical vapor deposition or chemical vapor deposition. Furthermore, if the material is aluminum oxide, it can constitute a coating produced by anodizing in a manner known to those skilled in the art.
[0025] The exterior component 10 includes a thin-film dielectric coating 110 on its support surface 101, which is translucent, i.e., at least transparent in the visible region. The layers of the thin-film dielectric coating 110 are deposited by the ALD method. Each layer in the thin-film dielectric coating 110 has a thickness of from 1 nanometer to several tens of nanometers. Due to this property, the support surface 101 of the exterior component 10 can be protected from chemical and environmental influences such as humidity and colored in a reproducible and robust manner by precisely selected interference effects. Therefore, the thickness of the thin-film dielectric coating 110 is uniform and constant over the entire surface thereof.
[0026] The support surface 101 can be structured by machining, such as machining by a hand-carved or numerically controlled machine tool, chemical machining, or laser machining. The structure is formed by valleys and ridges, and the distance between the valleys and ridges is, for example, at least 1 μm, and its appearance is advantageously maintained by the thin-film dielectric coating 110.
[0027] The thin-film dielectric coating 110 is formed by at least two thin dielectric layers including a base layer 111 and a termination layer 112 that overlap on the support surface 101. The base layer 111 is preferably made of Al2O3, and the termination layer 112 is preferably made of TiO2.
[0028] In particular, the termination layer 112 made of TiO2 advantageously ensures the chemical protection of the exterior component.
[0029] In the preferred exemplary embodiment of the present invention shown in FIG. 1, the thin-film dielectric coating 110 includes four intermediate layers 113 deposited between the base layer 111 and the termination layer 112. These intermediate layers 113 are alternately made of TiO2 and Al2O3 such that the intermediate layer 113 overlapping on the base layer 111 is made of TiO2 and the layer contacting the termination layer 112 is made of Al2O3.
[0030] In other exemplary embodiments, the thin-film dielectric coating 110 may comprise more than four or fewer intermediate layers 113, provided that an even number of intermediate layers 113 are present. In other words, the thin-film dielectric coating 110 may comprise at least two layers.
[0031] Advantageously, the base layer 111 has excellent chemical affinity with the support surface 101 on which it is deposited, which ensures very good adhesion of the base layer 111 and, consequently, the thin film dielectric coating 110, and makes it possible to increase the deposition rate of the base layer 111.
[0032] The thin-film dielectric coating 110 imparts interference colors to the exterior component 10, the hue of which is determined by the thickness of each layer of the thin-film dielectric coating 110, their arrangement and number, and the material of the support surface 101. Therefore, the interference colors produced by the features of the present invention are advantageously very precise.
[0033] In a preferred exemplary embodiment of the present invention, the layer within the thin film dielectric coating 110 has a thickness selected to impart interference colors to the exterior component 10 in CIELAB space in the reflection mode of a standard light source D65, with an observer of 10° and a measurement geometry of di:8°, characterized by parameters L*=[75;85], a*=[-45;-35], b*=[5;15], more specifically by parameters L*=79, a*=-39, b*=8.
[0034] Therefore, in this first modification, the exterior component 10 has a light green or turquoise green appearance.
[0035] In this embodiment, each layer of the thin-film dielectric coating 110 has a thickness of 1 to several tens of nanometers, for example, 1 nm to 90 nm. In particular, the base layer 111 has a thickness of 1 nm to 10 nm, the intermediate layer 113 has a thickness of 20 nm to 90 nm, and the terminal layer 112 has a thickness of 55 nm to 65 nm. More specifically, the intermediate layers 113 can have thicknesses of 25 nm to 30 nm, 75 nm to 85 nm, 15 nm to 25 nm, and 15 nm to 25 nm, respectively, from the intermediate layer 113 closest to the base layer 111 to the intermediate layer 113 closest to the terminal layer 112.
[0036] More generally, it should be noted that the embodiments and uses described above are non-limiting examples, and therefore other modifications are possible.
Claims
1. An exterior component (10) used in watches, jewelry or fine jewelry, comprising a substrate (100) having a support surface (101) made of a material containing at least 50% by mass of aluminum, wherein on the support surface (101) there is an Al that overlaps on the support surface (101). 2 O 3 The base layer (111) and TiO 2 An exterior component (10) characterized by having a translucent thin film dielectric coating (110) deposited, comprising at least two layers including a termination layer (112) made of the same material.
2. It includes an even number of intermediate layers (113), and at least two of the intermediate layers (113) are deposited between the base layer (111) and the terminal layer (112), and the intermediate layer (113) overlapping on the base layer (111) is TiO 2 and the layer contacting the terminal layer (112) is Al 2 O 3 and TiO 2 and Al 2 O 3 The exterior component (10) according to claim 1, which is alternately made of and.
3. The exterior component (10) according to claim 1, wherein the substrate (100) is formed by a body made of pure aluminum or an aluminum alloy, and the body comprises the support surface (101).
4. The exterior component (10) according to claim 1, wherein the substrate (100) comprises a body having a coating made of aluminum nitride, aluminum carbide, aluminum oxide, or aluminum carbonitride, and the coating comprises the support surface (101).
5. The exterior component (10) according to claim 2, wherein the thin film dielectric coating (110) comprises four intermediate layers (113).
6. The exterior part (10) according to claim 5, wherein the layer within the thin film dielectric coating (110) has a thickness selected to give the exterior part (10) interference colors characterized by the parameters L* = [75;85], a* = [-45;-35], b* = [5;15] in CIELAB space in the reflection mode of a standard light source D65, with a 10° observer and a di:8° measurement geometry.
7. The exterior component (10) according to claim 6, wherein the base layer (111) has a thickness of 1 nm to 10 nm, the intermediate layer (113) has a thickness of 20 nm to 90 nm, and the terminal layer (112) has a thickness of 55 nm to 65 nm.
8. The exterior component (10) according to claim 7, wherein the intermediate layers (113) have thicknesses of 25 nm to 30 nm, 75 nm to 85 nm, 15 nm to 25 nm, and 15 nm to 25 nm in order from the intermediate layer (113) closest to the base layer (111) to the intermediate layer (113) closest to the terminal layer (112).