Colored watch parts

Abstract

A watch component, particularly an external watch component, particularly a dial, including a body, wherein one surface thereof is at least partially covered with a coating that forms an optical coloring element, the coating comprising a superposition of successive layers on the surface, the first layer being made of at least one metallic material, the second layer being made of a semiconductor material, the third layer being made of at least one metallic material, optionally repeats of the second and third layers, one or more oxide layers, optionally top finishing layers such as acrylic and / or nitrocellulose finishing layers, particularly Zapon layers, and optionally one or more layers of metallic material, particularly chromium or titanium, interposed between two of the above-defined layers of the coating, the layers of which promote adhesion and / or partial absorption of light.

Description

[Technical Field] 【0001】 The present invention relates to a watch component, including a coating that colors the watch component or, more generally, forms an optical element for decoration. The present invention also relates to a watch, including at least one such watch component. The present invention also relates to a method for manufacturing such watch component. [Background technology] 【0002】 For example, there are old and traditional methods of coloring watch parts by depositing paint, varnish, lacquer, or enamel. 【0003】 Novel techniques involving the deposition of thin layers are now used as alternatives, as disclosed, for example, in Patent Documents 1 and 2. These solutions are based on the deposition of coatings comprising multiple thin layers, which allows for the acquisition of different colors. However, these existing methods have drawbacks, particularly their complexity and the difficulty in obtaining repeatable and robust colors in a manner suitable for industrial production. [Prior art documents] [Patent Documents] 【0004】 [Patent Document 1] European Patent Application Publication No. 3896193 [Patent Document 2] European Patent Application Publication No. 4060386 [Non-patent literature] 【0005】 [Non-Patent Document 1] "CIE15: Technical Report on Colorimetry," International Commission on Illumination, 2004. [Overview of the project] [Problems that the invention aims to solve] 【0006】 The general objective of the present invention is to provide a solution for coloring watch components that enables improvements on existing solutions. 【0007】 More specifically, the first objective of the present invention is to provide a solution for coloring watch components that enables the achievement of predetermined colors in a durable, robust, and repeatable manner. 【0008】 A second objective of the present invention is to provide a solution for coloring watch components in a simple manner that is compatible with industrial production. [Means for solving the problem] 【0009】 Therefore, the present invention relates to a watch component, particularly an external watch component, particularly a dial, which includes a body, one of which is at least partially covered with a coating that forms an optical coloring element, and the coating is on the surface, A first layer made of at least one metal material, The second layer of the semiconductor material, A third layer made of at least one metal material, Optionally, the second and third layers can be repeated. One or more oxide layers, Optionally, a top finish layer such as an acrylic and / or nitrocellulose finish layer, especially a Zapon layer, Optionally, one or more layers of a metallic material, particularly chromium or titanium, interposed between the two layers of the coating as defined above, wherein the layers promote adhesion and / or partial absorption of light. Based on watch components, including the superposition of successive layers. 【0010】 The present invention also relates to a method for manufacturing watch components, particularly external watch components, particularly dials, comprising a preliminary step of manufacturing the body of the watch component, the method comprising depositing a coating onto at least a portion of the surface of the body, the deposit of the coating, A first layer deposit made of at least one metallic material, Deposition of the second layer of semiconductor material, Deposition of at least one third layer made of a metallic material, Optionally, repetition of the deposition of the second and third layers, Deposition of one or more oxide layers, Optionally, deposition of an upper finishing layer such as an acrylic and / or nitrocellulose finishing layer, in particular a zapon layer, Optionally, deposition of one or more layers of a metallic material, in particular chromium or titanium, interposed between two of the said layers of the coating as defined above, the layer of chromium and / or titanium having a very small thickness of 2 nm or less in order to promote the adhesion of the two coating layers, or the layer of chromium and / or titanium having a thickness greater than 2 nm in order to form a layer of partial absorption, relating to a manufacturing method comprising the steps of. 【0011】 The present invention is more particularly defined by the claims. 【0012】 The objects, features, and advantages of the present invention are disclosed in detail in the following description of specific embodiments given as non-limiting examples with reference to the accompanying drawings. 【Brief Description of the Drawings】 【0013】 [Figure 1a] Figures 1a, 1b, and 1c schematically show cross-sectional views of the coating of a part according to three alternatives of a first embodiment of the present invention. [Figure 1b] Figures 1a, 1b, and 1c schematically show cross-sectional views of the coating of a part according to three alternatives of a first embodiment of the present invention. [Figure 1c] Figures 1a, 1b, and 1c schematically show cross-sectional views of the coating of a part according to three alternatives of a first embodiment of the present invention. [Figure 2a] Figures 2a and 2b schematically show cross-sectional views of the coating of a part according to two alternatives of a second embodiment of the present invention. [Figure 2b]Figures 2a and 2b schematically show cross-sectional views of the coating of a component according to two alternatives of the second embodiment of the present invention. [Figure 3] Figure 3 schematically shows a cross-sectional view of a component coating according to a third embodiment of the present invention. [Modes for carrying out the invention] 【0014】 By convention, the adjectives “upper” and “lower,” “top” and “bottom,” and the expressions “upper” and “lower” are used herein in reference to the orientation used in the drawings. In these drawings, the bottom layer is the layer intended to be applied in direct contact with the surface of the watch component body, and the top layer is the outward-facing layer that forms the final outer surface of the watch component. 【0015】 The simplified term "parts" will be used from this point forward to refer to watch components. 【0016】 Therefore, the objective of the present invention is to generate a selected color on the surface of a component. The present invention is based on the use of a coating that includes several specific overlay thin layers that form an optical element as a whole, the effect of which is to modulate the reflection behavior of light on the surface in order to favor a particular wavelength over others, i.e., a color scheme. 【0017】 The purpose of this effect is, of course, to enable the user to perceive a predetermined color and / or more generally, a decorative effect. For this reason, the effect occurs within the visible range of light. Hereafter, "visible range" refers to all visible wavelengths or a significant portion of the visible wavelength range. Therefore, the expression "visible range" may, for example, hereafter mean wavelengths in the range between 380 and 780 nm, or even between 380 and 650 nm, or even between 380 and 550 nm. The term "visible range" may also imprecisely mean only a portion of the theoretical visible range. 【0018】 As will be explained in detail below, the optical effects according to the concept of the present invention are obtained by stacking thin layers having selected optical properties. The overall optical effect is obtained from various absorption, reflection, and interference phenomena caused by the overlay layers. In particular, the selected material for each layer and the associated refractive index make it possible to define the optical properties required for each layer and the overall optical effect resulting from various combinations of layers. 【0019】 The refractive index is generally a complex number, as is well known, consisting of a real part n that defines the deflection of incident light rays by the interface between two given layers, and an imaginary part k that defines the extinction coefficient, which is a measure of the attenuation of the incident light wave. These values ​​depend on the wavelength, and for this reason, the refractive index is considered to be within the visible range from this point forward. 【0020】 In addition, the phrase "material-based" is used to mean the use of at least 50% by weight of the material in question. 【0021】 As described above, the present invention is based on the use of a specific coating that forms an optical coloring element that is disposed on all or part of the surface of the body of the component to be colored. 【0022】 More specifically, the present invention is based on the use of a particular coating comprising a first group including at least two reflective layers surrounding a layer of semiconductor material, and a second group including at least one oxide layer. 【0023】 The first group of coatings are in the following order, from bottom to top: - A first layer made of one or more metal materials, - The second layer of the semiconductor material, - A third layer made of one or more metal materials, Includes. 【0024】 The first and third layers thus form reflective layers; that is, their primary effect is to reflect incident light. The first and third layers, and any other reflective layers of the coating, preferably have the property of forming a medium having a refractive index in the visible range that includes a real part less than 3.5 and an imaginary part greater than 1, i.e., an extinction coefficient. The real part may have a maximum value (less than 3.5) in the visible range, and may form a wavelength coefficient that initially increases to this maximum value and then decreases with increasing wavelength. The imaginary part may increase with wavelength. 【0025】 These layers are preferably made of one or more metallic materials. Each of these layers may consist entirely of a single metallic material, or it may consist of a mixture of two or more metallic materials arranged in the same layer or in a continuous overlay layer. According to an advantageous embodiment, the metallic material is selected from gold, platinum, titanium, palladium, chromium, rhodium, silver, copper, tungsten, and aluminum, the latter of which can be sealed by a very thin layer of Al2O3 deposited by ALD (atomic layer deposition). Alternatively, any metallic material can be used. According to a simple embodiment, the first and third layers may each take the form of a metallic layer consisting entirely of a single metallic material, which may be identical or different for the two layers. 【0026】 In addition, according to one embodiment, the first layer has a thickness of 100 nm or more. This layer optically isolates the coating from the main body. The first layer also makes a significant contribution to the overall optical representation of the coating. The first layer is thicker than the other layers of the coating and can act as a substrate while simultaneously being an element of the coating. Alternatively, the first layer may be formed by the main body. 【0027】 According to one embodiment, the third layer has a thickness between 2 and 50 nm, moreover between 5 and 50 nm, moreover between 30 and 40 nm, and / or a thickness of 20 nm or more. 【0028】 As an example, the third layer is: - A layer of gold having a thickness between 5 and 50 nm, and moreover between 30 and 40 nm, and / or a thickness of 20 nm or more, - A layer of platinum, titanium, palladium, chromium, rhodium, or silver having a thickness of 5 to 50 nm, even more so between 30 to 40 nm, and / or 20 nm or more, or - A layer containing gold and / or platinum and / or titanium and / or palladium and / or chromium and / or rhodium and / or silver, having a thickness of 5 to 50 nm, and further between 30 to 40 nm, and / or 20 nm or more. You may choose from the following. 【0029】 In a favorable embodiment, as described below, gold is used as the first and / or third metallic layer, optionally combined with chromium. This is because gold is a robust material that is easy to deposit and exhibits good reproducibility from one manufacturing cycle to the next. 【0030】 Advantageously, the second layer of the semiconductor material has the property of forming a medium such that the refractive index in the visible range includes a real part greater than 2.5 and an imaginary part greater than 0.05, i.e., an extinction coefficient. The real part may have a maximum value (greater than 2.5) in the visible range, and may form a function of wavelength, initially increasing to this maximum value and then decreasing with increasing wavelength. The imaginary part may decrease with wavelength. The extinction coefficient is greater than 0.05, in particular for wavelengths lower than 550 nm, and even more so for wavelengths between 380 and 550 nm, between 380 and 650 nm, and between 380 and 780 nm. 【0031】 The second layer is based on one or more semiconductor materials. The second layer may consist entirely of a single semiconductor material, or it may consist of a mixture of two or more semiconductor materials arranged in the same layer or in two overlay layers. According to an advantageous embodiment, the semiconductor material may be silicon (Si), germanium (Ge), a combination of silicon (Si) and germanium (Ge), and gallium arsenide (GaAs) or tantalum oxynitride (TaOx N y The material is selected from group III to V semiconductor materials such as ). Note that the latter material may, as an alternative, be an insulator, semiconductor, or conductive depending on the degree of nitriding and oxidation, characterized by the values ​​of y and x, respectively. This implies that its refractive index is variable over a wide range of values. x N y It is possible to form a layer within the material that exhibits optical behavior similar to that of a semiconductor, or even similar to that of silicon (Si). Alternatively, any semiconductor material, preferably one with an extinction coefficient greater than 0.05, can be used. 【0032】 According to an advantageous embodiment, the second layer has a thickness between 5 and 50 nm. 【0033】 The use of silicon, more generally semiconductor materials, offers several advantages. The optical behavior of the second layer varies slightly with the angle of incidence, although this is different in silicon oxide, for example. This is because semiconductor materials generally have high refractive indices (within the visible range, the real part is greater than 2.5, even 3), and the trajectory of the light ray is naturally returned to perpendicular when it enters the material. In addition, the non-zero imaginary part of the refractive index of these materials implies that the interface plays a significant role in optical interference phenomena. This, in particular, makes it possible to firmly limit the iridescence effect of the resulting colors. 【0034】 Note that the semiconductor materials used are not oxidized, or at least not intentionally oxidized. Similarly, the semiconductor materials are not intentionally amorphous and are not hydrogenated. 【0035】 The first group of coating structures, which include the use of two layers of metal surrounding a layer of semiconductor material, is advantageous because it allows for modulation of the amount of light transmitted and reflected, particularly the intensity of light interacting with the semiconductor material layer. Furthermore, the thickness of the third metal layer may be selected to separate the second group of semiconductor material layers of the coating. In fact, even a relatively transparent metal such as gold with a small thickness, about 20 nm thick, is sufficient to significantly attenuate electromagnetic radiation. Thus, the third layer allows for the determination of the amount of light reaching the semiconductor material layer. 【0036】 Finally, the inventors discovered, surprisingly, that the combination of the first group possesses a highly advantageous property: it allows for the modulation of optical properties across the entire visible range in a flexible, robust, and reproducible manner, without iridescence. This result cannot be obtained with layers considered individually. 【0037】 The first group can thus be based on a large number of material combinations, such as Au(substrate) / Si / Au, Au(substrate) / Si / Ag, Ag(substrate) / Si / Au, Rh(substrate) / Si / Au, (Rh / Au)(substrate) / Si / Au, Cr(substrate) / Si / Au, etc. 【0038】 Optionally, the first group of structures may be modified to incorporate one or more layers of chromium Cr, or more generally, metal, particularly interposed between two of the three layers described above. Such chromium layers can perform two different functions. 【0039】 A thin, chromium, or more generally, metallic layer smaller than 2 nm, preferably between 0.5 and 2 nm, has a small optical effect and primarily functions as an adhesive layer. Such a layer may be interposed between any two layers of a coating to improve its adhesion. 【0040】 A chromium, or more generally, metallic, layer greater than 2 nm in thickness, additionally participates in the optical effects of the coating. In particular, such a layer serves the function of partial absorption of incident light. Such a layer may be associated with the first or third layer, as described above. This allows for the modification of reflection in a controlled and versatile manner, for example, at the interface between the semiconductor material layer and the third layer. Such a layer may be interposed between two layers of the first group, or it may be placed on top of the first group to form an interface with the second group of coatings, as described below. 【0041】 Alternatively, depending on the desired effect, any metal may be used instead of chromium, such as titanium (Ti), which can function as an adhesive layer and / or a partial absorption layer. 【0042】 Thus, the first group of coatings may have a structure reinforced by the presence of one or more layers of metal, such as chromium. In this way, the structure may consist of combinations such as Au(substrate) / Si / Cr-Au-Cr, Au(substrate) / Si / Au-Cr, Au(substrate) / Si / Cr-Au, Au(substrate)-Cr / Si / Au, Au(substrate)-Cr / Si / Cr-Au, Au(substrate)-Cr / Si / Cr-Au-Cr, Au(substrate)-Cr / Si / Au-Cr, and even Au(substrate) / Si / Cr, where the chromium layer forms the third layer described above. 【0043】 As a further alternative, instead of a series of layer combinations involving chromium layers such as Cr-Au-Cr, two different materials can be co-deposited simultaneously on the same region, thus enabling Au x Cr y It is possible to deposit mixed layers. A series of Cr-Au-Cr repeats is practically easier to implement and more robust, and remains a preferred embodiment. 【0044】 According to an alternative embodiment, the structure formed by the first group may be repeated, i.e., the first group may include an additional overlay of layers of semiconductor material and reflective layers according to a structure in which the layers of semiconductor material alternate with the reflective layers, and each of the layers of semiconductor material is interposed between two reflective layers. 【0045】 In addition, the coating may include a second group disposed on top of the first group described above. The second group includes at least one oxide layer. The second group, in particular, makes it possible to modulate the reflectivity of the coating and, for example, to increase the perceived brightness of the surface. 【0046】 The refractive index of each of these oxide layers within the visible range preferably includes a real part less than 3 and an imaginary part less than 0.05, and more preferably less than 0.01. 【0047】 According to one embodiment, one or more oxide layers of the second group each include two layers made of two different materials, and their refractive indices are different. 【0048】 According to one embodiment, each of the oxide layers of the second group consists of or is based on a material selected from SiO2, TiO2, Al2O3, Si3N4, Ta2O5, TaO x N y 、AlO x N y 、and TiO x N y In the case of the latter ternary materials, the selected stoichiometry is such that the material has optical properties similar to those of other oxides. 【0049】 According to one embodiment, the second group is - a layer of silicon oxide SiO2 having a thickness between 20 and 140 nm, preferably between 40 and 75 nm, and / or - a layer of titanium oxide TiO2 having a thickness between 5 and 100 nm, preferably between 5 and 50 nm, consisting of. 【0050】 In all cases, the thickness of the oxide layers is minimized to minimize the iridescence they produce and to have good industrial robustness. 【0051】 In addition to contributing to the definition of the optical properties of the coating, this second group also enables the formation of a protective layer for the coating, thereby increasing the environmental robustness of the stacked coating layers. 【0052】 Finally, the second group optionally includes an upper finishing layer, such as an acrylic and / or nitrocellulose layer, particularly a Zapon layer, which is placed on the oxide layer for this purpose. Alternatively, the finishing layer may include other materials, such as sol-gel type materials. The finishing layer may also include functional compounds, such as colorants and diffusing particles. When using such finishing layers, such as an acrylic and / or nitrocellulose layer, particularly a Zapon layer, it is noted that it is advantageous to deposit a final layer of metal, particularly chromium, having a thickness of less than 2 nm and preferably greater than 0.5 nm, on top of the final oxide layer, i.e., the top layer, in order to form an adhesive layer for the finishing layer. In fact, it is noted that such a layer significantly enhances the adhesion of the acrylic and / or nitrocellulose finishing layer to the structure. 【0053】 It should be further noted that when acrylic and / or nitrocellulose finishing layers are used, their optical properties should be considered. In particular, certain products used for such finishing layers, such as "Zapon," have a refractive index close to that of SiO2 oxide. In this case, it may be preferable not to deposit the SiO2 oxide layer, as the optical effect of the SiO2 oxide layer may be masked to a considerable extent by the effect of the finishing layer. 【0054】 The second group preferably does not include a metal layer that produces an optical effect. To enhance the adhesion between layers, it is possible to simply employ a thin metal layer having a thickness of less than 2 nm, for example, a layer of chromium and / or titanium. 【0055】 Generally, some parts of the stack forming the coating may be doubled to adjust or enhance their effect. For example, the first group of layers may be doubled, and for this reason, an Au(substrate) / Si / Au / Si / Au stack may be present, for example, with or without an intervening Cr layer at some or all of the interfaces as described above. In such a configuration, the thickness of the layers may differ for a given material, for example, the thickness of the first Si layer may differ from the thickness of the second Si layer. In addition, whether intentional or not, the second Si layer may have a different degree of residual oxidation than the first layer. Similarly, the second group of layers may be doubled, and for this reason, a TiO2 / SiO2 / TiO2 / SiO2 stack may be present instead of a TiO2 / SiO2 stack, or an SiO2 / TiO2 / SiO2 / TiO2 / Zapon stack may be present instead of an SiO2 / TiO2 / Zapon stack. 【0056】 The coating of the present invention allows for numerous combinations of layers, enabling a wide range of colors and expressions, particularly those with subtle red, purple, blue, green, and brown tones. 【0057】 The following table shows some examples of the fabricated layers, along with the resulting colors. Lightness L* and chromaticity a* and b* were evaluated within the space defined by the International Commission on Illumination, CIE L*a*b*, as shown in Non-Patent Literature 1. Measurements were performed in SCI (including specular reflection) and SCE (excluding specular reflection) modes, and are shown below in SCI mode. 【0058】 [Table 1] 【0059】 In general, this approach makes it possible to obtain a very wide range of color panels, especially colors other than black, through the optical interference of light. Black can be defined as a color with coordinates L*a*b* such that -2≦a*≦2, -2≦b*≦2, and L*≦30. 【0060】 Figures 1a to 1c schematically illustrate alternative examples of the first embodiment of the coating according to the present invention. In all of these alternative examples, the first group of coatings includes the same structure: two gold layers surrounding a silicon layer. The first two alternative examples include a second group consisting of two oxide layers, which are a silicon dioxide (SiO2) layer and a titanium dioxide (TiO2) layer, respectively, with the order of the layers reversed in the second alternative example. The third alternative example in Figure 1c has the same stacking as the first alternative example in Figure 1a, with a Zapon finishing layer added on top. 【0061】 Figures 2a and 2b schematically illustrate alternative examples of a second embodiment of the coating according to the present invention. In the embodiment in Figure 2a, the first group of coatings includes a structure of two gold layers surrounding a silicon layer. The second group includes an oxide layer, in this case a titanium dioxide (TiO2) layer, on which a Zapon layer is added. Figure 2b illustrates an alternative embodiment of the embodiment in Figure 2a, in which a thin layer of chromium is interposed between each set of adjacent continuous layers in the embodiment in Figure 2a to increase adhesion between these layers. 【0062】 Finally, Figure 3 illustrates a third embodiment of the coating according to the present invention. The first group includes three relatively thick layers of chromium, each positioned on each of the three basic layers of the first group, to provide optical complementation to the first group. In other words, the first layer forming the substrate includes a thick layer of gold, amplified by an overlay of chromium layers, and the third layer of gold is amplified by its positioning between the two layers of chromium. The second group is identical to that of the embodiment shown in Figure 1c. 【0063】 The coatings of the present invention described above may be combined with other features that contribute to the coloring effect of the parts, or more generally, to the decorative effect. For example, the decorated surface of a part may include a surface structuring that is entirely or partially covered by the coating described above. The coating has a total thickness that is small enough to follow and protect the contours of the surface structuring. The surface structuring may consist of, for example, sunray brushing, sandblasting, satin finish, brushing, snail finish, at least one Côtes de Genève, perlage, circular, and / or repeating decoration of any type of motif. 【0064】 The body may be made of a variety of materials, particularly brass, gold, ceramic, especially zirconia or alumina, sapphire, silicon, nickel (Ni), or nickel-phosphorus (NiP). The body may be made entirely of one material or may contain multiple materials. In particular, the colored surface of the body may include layers of material to facilitate the realization of surface structuring, such as the above, within its thickness. Such layers may be, for example, layers of silver. 【0065】 The components may be watch parts, such as external watch parts like the dial, bezel, bezel disc, glass, case, and bracelet, or watch movement components such as weights, blanks, bridges, mainspring covers, or stop-click covers. 【0066】 The present invention also relates to a method for manufacturing watch components, particularly external watch components, and particularly a dial, comprising a preliminary step for manufacturing the body of the watch component, the method comprising depositing a coating onto at least a portion of the surface of the body, the deposit of the coating - A first layer deposit made of at least one metallic material, - Deposition of the second layer of semiconductor material, - A third layer of deposit made of at least one metallic material, - Optionally, repeated deposition of the second and third layers, - Deposition of one or more oxide layers, - Optionally, deposition of top finishing layers such as acrylic and / or nitrocellulose layers, particularly layers of Zapon. - Optionally, the deposition of one or more layers of a metallic material, particularly chromium or titanium, interposed between the two layers of the aforementioned coating, wherein the chromium layer has a thickness of 2 nm or less to promote adhesion between the two coating layers, or the chromium layer has a thickness greater than 2 nm to form a layer of partial absorption. This includes the following steps. 【0067】 The deposition of individual layers according to the steps described above is carried out in the order shown, with the individual layers being overlaid on top of each other, starting from the surface of the part body. Thus, these layers are arranged, overlaid, and adjacent to any intermediate metal layers that may be interposed between these individual layers according to the arbitrary deposition described above, with the exception of the chromium layer in particular, in the order shown. 【0068】 According to an advantageous embodiment, all or part of the coating layer is deposited by physical vapor deposition (PVD), for example by vacuum evaporation, cathode sputtering, or ion beam, by chemical deposition (CVD), or by atomic layer deposition (ALD). 【0069】 Furthermore, and also advantageously, if present, top finishing layers such as acrylic and / or nitrocellulose layers can be deposited, and all layers of the coating, except for the Zapon layer, can be deposited using the same technique during the same manufacturing cycle. These deposits are preferably carried out without air permeation between the deposits of two consecutive layers. 【0070】 Alternatively, different deposition techniques, including PVD, CVD, and ALD techniques, may be used for different layers of the coating, provided they are compatible. 【0071】 As a first embodiment of the manufacturing method, vacuum evaporation is used, which allows for the deposition of thin layers of the elements Si, Cr, Au, TiO2, and SiO2 with very well-controlled thicknesses. In this case, the semiconductor layer consists of metallic layers of Si, Au, and optionally Cr, an optional adhesive layer of Cr, and oxide layers of TiO2 and SiO2. 【0072】 As a second embodiment of the manufacturing method, cathode sputtering is used, which similarly allows for the deposition of thin layers of the elements Si, Cr, Au, TiO2, and SiO2 with very well-controlled thicknesses. In this case, the semiconductor layer consists of metallic layers of Si, Au, and optionally Cr, an optional adhesive layer of Cr, and oxide layers of TiO2 and SiO2. 【0073】 As a third embodiment of the manufacturing method, with a very well controlled thickness, TaO x N y Cathode sputtering is used, which allows for the deposition of thin layers of the elements Cr and Au. In this case, the semiconductor layer is TaO x N y A metal layer of Au and optionally Cr, an optional adhesive layer of Cr, and TaO x N y It consists of the upper layer. 【0074】 Various embodiments of deposition techniques known to those skilled in the art can be used. For example, according to ion beam-assisted PVD technology, Ar may be introduced onto the component during deposition to increase the density of the layer. The same ion beam may be supplied with O2 or N2 to promote oxidation and / or nitridation of the coatings, respectively. 【0075】 During deposition, the properties of the deposited layers can be observed in known ways. For example, a quartz microbalance placed in the deposition chamber allows for highly accurate observation of the deposited thickness. Similarly, during deposition, it is possible to analyze the transmission or reflection of light in the deposited layers, thus enabling the targeting of specific optical targets rather than just thickness targets. 【0076】 Specifically, the chamber of the deposition apparatus is placed under vacuum pressure during the deposition cycle. However, the residual atmosphere always contains residual gases such as O2, H2O, or N2, which means that some degree of unintentional partial oxidation and / or nitriding is possible. This unintentional phenomenon can be minimized, or even eliminated, by properly preparing the deposition apparatus, especially by cleaning it. Such partial oxidation and / or nitriding can affect the optical properties and thus the overall representation of the deposited coating. Where appropriate, it is possible to adjust the layer thickness to counteract and eliminate such unintentional optical effects and obtain the correct representation. 【0077】 Measurements showed that the Si semiconductor material deposited according to the present invention exhibits optical behavior close to that of pure, unoxidized Si. Specifically, refractive index measurements in a "clean" apparatus (long pump time) with a low residual oxygen partial pressure yielded refractive index n of 4.04 at an incident wavelength of 550 nm and 3.87 at an incident wavelength of 630 nm, which are very close to the values ​​for pure silicon (4.39 for amorphous silicon and 4.08 for crystalline silicon at 630 nm). Refractive index measurements in a "dirty" apparatus (short pump time) yielded 3.35 at an incident wavelength of 550 nm and 3.20 at an incident wavelength of 630 nm, which, although short, are still far from the value of 1.47 for silicon dioxide (SiO2). Similarly, the extinction coefficient k remained very high, far above 0.05 across most of the visible portion of the spectrum. Therefore, the Si substrate material deposited by the method of the present invention always acts as a semiconductor, regardless of the state of the deposition apparatus or any possible natural phenomenon such as unintentional oxidation. 【0078】 In summary, the above considerations demonstrate that the above invention can be carried out based on a coating comprising the first group having a second layer of semiconductor material. The semiconductor material may have oxidation, particularly unintentional oxidation, which is negligible or can be offset by adjusting the thickness of the coating layer in order to obtain the desired results, particularly the desired color. 【0079】 Finally, the present invention has the advantage of simplifying the manufacturing method, particularly through the use of a second layer of semiconductor material. Furthermore, the semiconductor material offers advantageous optical properties. In particular, the semiconductor material has a high refractive index, is partially absorbent (with an extinction coefficient k > 0.05 over most of the visible range), and is robust (enabling stable, renewable industrial deposition over time). 【0080】 The present invention has numerous other advantages. In addition to the resulting reflectance spectra, the durability of the superposition, i.e., the invariance of the representation over time, and its manufacturing robustness (reproducibility from one manufacturing batch to the next, the number of layers, low and thin thicknesses where possible, multiple layers where compatible, and even a single layer for all superpositions, depending on the deposition technique) are equally important. 【0081】 Furthermore, the following advantages of the present invention can be listed. It can be used for both small-scale and large-scale production in an industrial and reproducible manner; The superposition of layers can be carried out in a simple manner within the same deposition equipment and within the same period; Strength and durability; Due to the numerous influencing parameters, multiple colors are possible from the same basic raw material; Obtain the target representation, in particular the target color, for example, a color according to the CIE L*a*b* standard, especially a color different from black, or a color outside the range defined by -2≦a*≦2 and -2≦b*≦2 and L*≦30; Optimization across the entire visible spectrum, not just a single wavelength or limited range; If there is any iridescence at all, it's only a small amount. 【0082】 As described above, in order to promote adhesion between the two layers, it is possible to use an ultrathin layer of metal less than 2 nm thick, particularly a layer of chromium or titanium, at at least one of the interfaces between the two layers of the coating. 【0083】 This effect has been found to be particularly excellent for promoting the adhesion and / or robustness of finishing layers, such as acrylic and / or nitrocellulose finishing layers, for example, Zapon layers. This approach is therefore applicable in all embodiments foreseen by the present invention. This approach may be implemented to promote the adhesion and / or robustness of finishing layers, regardless of the type of layer and / or underlying structure. 【0084】 More generally, these characteristics can be generalized to any finishing layer deposited on any coating on the surface of a part. 【0085】 Therefore, the present invention relates to watch components, particularly external watch components, and especially to dials, including a body, one surface thereof being at least partially covered by a coating, the coating comprising a finishing layer such as an acrylic and / or nitrocellulose finishing layer, particularly a Zapon layer, and an intermediate layer made of a metallic material, particularly chromium or titanium, having a thickness of less than 2 nm, on which the finishing layer is deposited to promote adhesion of the finishing layer. 【0086】 The present invention also relates to a method for manufacturing watch components, particularly external watch components, and particularly a dial, which includes a preliminary step of manufacturing the body of the watch component, the method comprising depositing a coating onto at least a portion of the surface of the body, the deposit of the coating, - Deposition of a layer of metallic material, particularly chromium or titanium, having a thickness of 2 nm or less, and then, - A layer of finishing layer, particularly a layer of Zapon, directly deposited onto the layer of metal material, such as an acrylic and / or nitrocellulose finishing layer, wherein the finishing layer has improved adhesion due to the layer of metal material. This includes the following steps. 【0087】 The present invention has been described in relation to a coating comprising a second group comprising one or more oxide layers. In all cases, as described above, each oxide layer of the second group can be replaced with a layer of semiconductor material in order to take advantage of the favorable properties of the semiconductor material. For this reason, according to one embodiment, the coating comprises a second group disposed on the first group described above, wherein the second group is, for example, TaO x N y It includes one or more layers of semiconductor material, such as a layer of [material name].

Claims

[Claim 1] A watch component, particularly an external watch component, particularly a dial, including a body, wherein one surface thereof is at least partially covered with a coating that forms an optical coloring element, and the coating is on the surface, A first layer made of at least one metal material, The second layer of the semiconductor material, A third layer made of at least one metal material, Optionally, the second and third layers can be repeated. One or more oxide layers, Optionally, one or more layers of a metallic material, particularly chromium or titanium, interposed between the two layers of the coating as defined above, wherein the layers promote adhesion and / or partial absorption of light. Including the superposition of successive layers, Watch parts. [Claim 2] The first and / or third layer is made of a material having a refractive index within the visible range, including a real portion less than 3.5 and an extinction coefficient greater than 1, and / or The second layer is made of a material having a refractive index within the visible range, including a real portion greater than 2.5 and an extinction coefficient greater than 0.05, and / or The oxide layer is made of a material having a refractive index within the visible range, which includes a real portion less than 3 and an extinction coefficient less than 0.05, and even less than 0.

01. The watch component according to claim 1. [Claim 3] The aforementioned layer has a thickness of 100 nm or more and / or is entirely made of one or more metallic materials selected from gold, platinum, titanium, palladium, chromium, rhodium, silver, copper, tungsten, and aluminum. The watch component according to claim 1 or 2. [Claim 4] The second layer has a thickness between 5 and 50 nm and / or is entirely silicon Si, germanium Ge, a combination of silicon Si and germanium Ge, and gallium arsenide GaAs or tantalum oxynitride (TaO ｘ N ｙ It consists of semiconductor materials selected from the III to V semiconductor materials, A watch component according to any one of claims 1 to 3. [Claim 5] The third layer is a layer of gold having a thickness between 2 and 50 nm, and moreover between 5 and 50 nm, and / or the entire third layer is made of one or more metallic materials selected from gold, platinum, titanium, palladium, chromium, rhodium, silver, copper, tungsten, and aluminum, or the third layer is a layer of gold having a thickness between 5 and 50 nm, and moreover between 30 and 40 nm, and / or a thickness greater than 20 nm. A watch component according to any one of claims 1 to 4. [Claim 6] The aforementioned one or more oxide layers include two layers, each made of two different transparent materials having different refractive indices. Or, SiO ２ , TiO ２ , Al ２ O ３ , Si ３ N ４ , Ta ２ O ５ , TaO ｘ N ｙ , AlO ｘ N ｙ and TiO ｘ N ｙ comprising one or more layers of a material selected from Alternatively, the one or more oxide layers or semiconductor material layers are Silicon oxide SiO2 having a thickness between 40 and 140 nm, preferably between 40 and 75 nm. ２ The layers, and / or Titanium oxide (TiO) having a thickness between 5 and 100 nm, preferably between 5 and 50 nm. ２ layers, Includes, A chromium layer having a thickness of 2 nm or less may be optionally added to promote adhesion of one or more layers. A watch component according to any one of claims 1 to 5. [Claim 7] To promote adhesion between the two layers of the coating, the coating includes and / or comprises at least one layer of metallic material, particularly chromium, having a thickness between 0.5 and 2 nm, placed between the two layers of the coating. To form a layer of partial absorption that alters the optical behavior at the interface between the two layers of the coating, the coating includes at least one layer of a metallic material, particularly chromium, having a thickness of 2 nm or more, disposed between the two layers of the coating. A watch component according to any one of claims 1 to 6. [Claim 8] Surface structuring applied to all or part of the surface of the body includes, in particular, surface structuring such as sunray brushing, sandblasting, satin finish, brushing, snail finish, at least one Côtes de Genève, perlage, circular, and / or repeating decoration of any type of motif, wherein the coating is at least partially placed on the surface structuring and is sufficiently thin to follow and protect the contour of the surface structuring. A watch component according to any one of claims 1 to 7. [Claim 9] The aforementioned body is made of brass, gold, ceramic, especially zirconia or alumina, sapphire, silicon, nickel (Ni), or nickel-phosphorus (NiP), and / or a dial, bezel, bezel disc, glass, case, bracelet, or watch movement components such as weights, blanks, bridges, mainspring covers, or stop-click covers. A watch component according to any one of claims 1 to 8. [Claim 10] The coating forms an optical colored element of a color different from black, which has the coordinates L*a*b*-2≦a*≦2, -2≦b*≦2, and L*≦30. A watch component according to any one of claims 1 to 9. [Claim 11] The coating includes an upper finishing layer such as an acrylic and / or nitrocellulose finishing layer, particularly a Zapon layer. A watch component according to any one of claims 1 to 10. [Claim 12] A clock, particularly a miniature clock, comprising the clock component described in any one of claims 1 to 11. [Claim 13] A method for manufacturing watch components, particularly external watch components, particularly a dial, comprising a preliminary step of manufacturing the body of the watch component, the method comprising depositing a coating onto at least a portion of the surface of the body, the deposit of the coating being A first layer deposit made of at least one metallic material, Deposition of the second layer of semiconductor material, A third layer deposit made of at least one metallic material, Optionally, the deposition of the second and third layers is repeated. Deposition of one or more oxide layers, Optionally, deposit of a top finish layer such as an acrylic and / or nitrocellulose finish layer, particularly a layer of Zapon. Optionally, the deposition of one or more layers of a metallic material, particularly chromium or titanium, interposed between the two layers of the coating as defined above, wherein the chromium layer has a very small thickness of 2 nm or less to promote adhesion between the two coating layers, or the chromium layer has a thickness greater than 2 nm to form a layer of partial absorption. The steps include, Manufacturing method. [Claim 14] All or part of the layer of the coating is deposited by physical vapor deposition (PVD), particularly by vacuum evaporation or cathode sputtering, or by chemical deposition (CVD), or by atomic layer deposition (ALD). The manufacturing method according to claim 13. [Claim 15] If present, all of the layers of the coating, except for the upper finishing layers such as acrylic and / or nitrocellulose layers, particularly the Zapon layer, are deposited in the same manner within the same manufacturing cycle. The manufacturing method according to claim 13 or 14. [Claim 16] To determine the end of the deposition step as a function of measurement, the deposition step includes measuring the thickness of the deposited layer and / or measuring the light transmission or reflection of the deposited layer. The manufacturing method according to any one of claims 13 to 15.

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