Exterior component with laminated protective interference layer

Abstract

The protective layer covering the circuit board provides an exterior component that does not impair the appearance. [Solution] An exterior component (10) for a watch, jewelry, or fine jewelry, comprising a substrate (100) having a metal surface (101) made of a precious metal or precious metal alloy, wherein the complex refractive index at a wavelength of 550 nm on the metal surface (101) is less than 1 (real part n < 1) and greater than 2 and less than 3 (imaginary part k < 2

Description

Technical Field

[0001] The present invention relates to the field of watches, jewelry or fine jewelry, and more particularly to exterior parts used for 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 an object, as generally understood in the above-mentioned fields.

Background Art

[0003] In the fields of watches, jewelry and fine jewelry, aesthetics is generally a major objective.

[0004] For example, in the watch field, exterior parts such as dials enable a watch brand to stand out from competing companies, form the brand identity, and help attract potential customers.

[0005] The dial generally includes a substrate made of a metal material (e.g., brass) or a precious metal such as gold or silver. These metal materials are prone to corrosion and / or discoloration, especially when used in layers. To protect the substrate from any chemical damage, it is generally covered with a protective layer such as varnish (e.g., zapon). The protective layer has sufficient water resistance and is about several micrometers thick, for example, 10 micrometers or more, so as to provide effective protection.

[0006] At such a thickness, the protective layer impairs the visual appearance of the structural processing part (structuring) of the substrate or the color of the substrate. This is particularly true when the substrate has a structural processing part, because it is necessary to further increase the thickness of the protective layer to be effective.

Summary of the Invention

Means for Solving the Problems

[0007] ​The present invention aims to improve the aforementioned drawbacks. For this purpose, it relates to an exterior component for use in a timepiece, jewelry or fine jewelry, comprising a substrate having a metal surface, the metal surface being made of a noble metal or a noble metal alloy in solid form or as a thin film deposited on the substrate (e.g., by PVD or galvanic deposition), and on the metal surface having a real part n of the complex refractive index at a wavelength of 550 nm less than 1 (n < 1) and an imaginary part k greater than 2 and less than 3 (2 < k < 3), and to an exterior component on which a laminate of thin film dielectric coatings is deposited.

[0008] Each layer in the laminate of thin film dielectric coatings consists of a layer deposited by the ALD deposition method, and the laminate is formed by at least one alternating arrangement of a layer made of TiO2 and a layer made of Al2O3, and comprises a terminal layer made of TiO2 and a base layer made of TiO2 or Al2O3 on the metal surface of the substrate.

[0009] Advantageously, the present invention makes it possible to provide vivid and accurate colors to the exterior component while ensuring chemical and mechanical protection of the exterior component.

[0010] In certain embodiments, the present invention can further comprise one or more of the following features, individually or in any technically possible combination.

[0011] In certain embodiments, the metal surface of the substrate is made of platinum or a platinum alloy.

[0012] In certain embodiments, the metal surface of the substrate is made of a gold alloy containing 75% by mass of gold and 25% by mass of silver and / or copper so as to be 100%.

[0013] In certain embodiments, the laminate of thin film dielectric coatings comprises two layers, and the base layer is made of Al2O3.

[0014] In certain embodiments, the base layer has a thickness of 1 nm to 10 nm or 2 nm to 8 nm, and the termination layer has a thickness of 10 nm to 30 nm or 15 nm to 25 nm.

[0015] In a particular embodiment, the metal surface of the substrate is made of a gold alloy comprising 75% by mass of gold, 4.5% to 5.5% by mass of silver, and 19.5% to 20.5% by mass of copper, with the total being equal to 100%.

[0016] In a particular embodiment, the laminate of thin-film dielectric coatings comprises three layers, including an intermediate layer made of Al2O3 sandwiched between the base layer and the termination layer, with the base layer and termination layer themselves being made of TiO2.

[0017] In certain embodiments, the base layer and termination layer have a thickness of 35 nm to 55 nm or 40 nm to 50 nm, and the intermediate layer has a thickness of 50 nm to 70 nm or 55 nm to 65 nm.

[0018] In a particular embodiment, the metal surface of the substrate is made of a gold alloy comprising 75% by mass of gold, 15% to 16% by mass of silver, and 9% to 10% by mass of copper, with the total amount equal to 100%. [Brief explanation of the drawing]

[0019] Other features and advantages of the present invention will become apparent from the following detailed description, given as non-limiting examples with reference to Figures 1 and 2. [Figure 1] A schematic cross-sectional view of an exterior component according to a preferred embodiment of the present invention is shown. [Figure 2] A schematic cross-sectional view of an exterior component according to a preferred embodiment of the present invention is shown.

[0020] It should be noted that the diagram is not drawn to scale for clarity. [Modes for carrying out the invention]

[0021] The present invention relates to an exterior component 10 for use in a timepiece, jewelry or fine jewelry, and includes a substrate 100 having a metal surface 101 made of a noble metal or a noble metal alloy, that is, an alloy containing at least 30% by mass of a noble metal.

[0022] The exterior component 10 according to the present invention is schematically shown in FIGS. 1 and 2, and is particularly suitable for forming a dial for a timepiece or any other internal part of a timepiece, preferably.

[0023] The exterior component 10 includes a laminate of thin film dielectric coatings 110 on its metal surface 101. The thin film dielectric coatings 110 are translucent, that is, at least transparent in the visible region, and each is deposited by an atomic thin film deposition method known to those skilled in the art by the acronym "ALD" of "Atomic Layer Deposition". Each layer of the thin film dielectric coating 110 has a thickness of several nanometers to several tens of nanometers. Due to this property, the metal surface 101 of the exterior component 10 can be protected from chemical attack and colored in a reproducible and durable manner by accurately selected interference effects. Therefore, the thickness of the thin film dielectric coating 110 is uniform and constant over its entire surface.

[0024] The metal surface 101 can have a structured portion by, for example, machining, such as by hand carving or machining by a numerically controlled machine tool, by chemical machining or by laser machining. The structured portion is formed by valleys and ridges, and the distance between the valleys and the ridges is, for example, at least 1 μm.

[0025] The laminate of the thin film dielectric coatings 110 is formed by at least one alternating arrangement of a layer made of TiO2 and a layer made of Al2O3, and includes a terminal layer 111 made of TiO2 and a base layer 112 made of TiO2 or Al2O3 on the metal surface 101.

[0026] In this case, it is understood that the properties of the base layer 112 are determined by the number of thin film dielectric coatings 110, particularly whether the number of thin film dielectric coatings is even or odd.

[0027] The interference color obtained by the combination of the laminate of the thin film dielectric coatings 110 and the metal surface 101 varies particularly depending on the thickness of each thin film dielectric coating 110, their arrangement and their number, as well as the material from which the metal surface 101 is made.

[0028] In particular, the present invention proposes a specific arrangement of a laminate of thin film dielectric coatings 110 associated with a metal surface 101 made of a noble metal or noble metal alloy having a real part n (n < 1) less than 1 and an imaginary part k (2 < k < 3) greater than 2 and less than 3 at a wavelength of 550 nm.

[0029] Advantageously, by the nature and thickness of the layers of the laminate of the thin film dielectric coatings 110 and the choice of the material of the support surface 101, the interference color generated by the features of the present invention is very accurate.

[0030] In a particular embodiment of the present invention, the metal surface 101 is made of gold or platinum, or an alloy of any of these metals, and can include iridium, palladium, platinum, rhodium, etc.

[0031] In particular, in the embodiment schematically shown in FIG. 1, the laminate of the thin film dielectric coatings 110 comprises two layers and includes a base layer 112 made of Al2O3.

[0032] The base layer 112 has a thickness of from 1 nm to 10 nm, or from 2 nm to 8 nm, and the termination layer 111 has a thickness of from 10 nm to 30 nm, or from 15 nm to 25 nm.

[0033] In this exemplary embodiment, the metal surface 101 is made of a gold alloy comprising, for example, 75 mass% gold and 25 mass% silver and / or copper to make up 100%, or a gold alloy comprising 75 mass% gold, 4.5 mass% to 5.5 mass% silver, and 19.5 mass% to 20.5 mass% copper.

[0034] As a result, the metal surface 101 has a complex refractive index where the real part n is equal to 0.7 and the imaginary part k is equal to 2.5 at a wavelength of 550 nm.

[0035] The interference color obtained using the above parameters, in the CIELAB color space, with the transmission mode of the standard light source D65, and using a 10° observer and a d:0° measurement geometry, is characterized by the parameters L*=66, a*=34, b*=52 and has an orange appearance.

[0036] According to another exemplary embodiment of the present invention schematically shown in Figure 2, the laminate of the thin film dielectric coating 110 comprises three layers, including an intermediate layer 113 made of Al2O3 sandwiched between a base layer 112 and a termination layer 111, the base layer 112 and the termination layer 111 themselves being made of TiO2.

[0037] The base layer 112 and the termination layer 111 have a thickness of 35 nm to 55 nm or 40 nm to 50 nm, and the intermediate layer 113 has a thickness of 50 nm to 70 nm or 55 nm to 65 nm.

[0038] In this exemplary embodiment, the metal surface 101 is made of a gold alloy comprising, for example, 75 mass% gold and 25 mass% silver and / or copper, for example, 15 mass% to 16 mass% silver and 9 mass% to 10 mass% copper, to a total of 100%.

[0039] As a result, the metal surface 101 has a complex refractive index where the real part n is equal to 0.4 and the imaginary part k is equal to 2.2 at a wavelength of 550 nm.

[0040] The interference color obtained using the above parameters is characterized in the CIELAB color space by parameters L*=76, a*=21, b*=-27, using a standard light source D65 in transmission mode, a 10° observer, and a d:0° measurement geometry, and has a pink appearance.

[0041] In another exemplary embodiment, the metal surface 101 may be made of a gold alloy comprising 75% by mass of gold, 12% to 13% by mass of silver, and 12% to 13% by mass of copper, with the total being equal to 100%.

[0042] More generally, it should be noted that the embodiments and uses described above are non-limiting examples, and therefore other modifications are possible.

[0043] In particular, the substrate 100 is formed of an object on which a metal layer can be deposited, for example, by electrodeposition, by physical vapor deposition known to those skilled in the art as the acronym "PVD", or by chemical vapor deposition known to those skilled in the art as the acronym "CVD". Thus, the metal surface 101 is formed by the metal layer thus deposited. Such a metal layer has a thickness of 50 nm to 10 μm, preferably 50 nm to 500 nm.

Claims

1. An exterior component (10) for use in watches, jewelry, or fine jewelry, comprising a substrate (100) having a metal surface (101) made of a precious metal or precious metal alloy, wherein the complex refractive index of the metal surface (101) at a wavelength of 550 nm has a real part n less than 1 (n < 1) and an imaginary part k greater than 2 and less than 3 (2 < k < 3), and a laminate of thin-film dielectric coatings (110) each consisting of an atomic thin film is deposited on the metal surface (101), wherein the laminate is TiO 2 Layers created with Al 2 O 3 Formed by at least one alternating arrangement with layers made of TiO 2 The terminal layer (111) made of and TiO on the metal surface (101) 2 or Al 2 O 3 An exterior component (10) characterized by comprising a base layer (112) made of [material].

2. The exterior part (10) according to claim 1, wherein the metal surface (101) is made of gold, platinum, or an alloy of any of these metals.

3. The exterior part (10) according to claim 2, wherein the metal surface (101) is made of a gold alloy containing 75% by mass of gold and 25% by mass of silver and / or copper to make up 100% of the alloy.

4. The laminate of the thin film dielectric coating (110) includes two layers, and the base layer (112) is Al 2 O 3 The exterior component (10) according to claim 1, made of.

5. The exterior component (10) according to claim 4, wherein the base layer (112) has a thickness of 1 nm to 10 nm or 2 nm to 8 nm, and the terminal layer (111) has a thickness of 10 nm to 30 nm or 15 nm to 25 nm.

6. The exterior component (10) according to claim 5, wherein the metal surface (101) is made of a gold alloy comprising 75% by mass of gold, 4.5% to 5.5% by mass of silver, and 19.5% to 20.5% by mass of copper, the total of which is equal to 100%.

7. The laminate of the thin film dielectric coating (110) comprises three layers, with Al sandwiched between the base layer (112) and the termination layer (111). 2 O 3 It includes an intermediate layer (113) made of TiO, and the base layer (112) and the terminal layer (111) themselves are TiO 2 The exterior part (10) according to claim 1, which is made of the material described above.

8. The exterior component (10) according to claim 7, wherein the base layer (112) and the terminal layer (111) have a thickness of 35 nm to 55 nm or 40 nm to 50 nm, and the intermediate layer (113) has a thickness of 50 nm to 70 nm or 55 nm to 65 nm.

9. The exterior part (10) according to claim 1, wherein the metal surface (101) is made of a gold alloy comprising 75% by mass of gold, 15% to 16% by mass of silver, and 9% to 10% by mass of copper, with the total being equal to 100%.

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