Method for producing a lacquered timepiece component

Abstract

The invention relates to a method for producing a timepiece component (10), characterised in that the method comprises the following steps: - Providing (E1) a support member (1) comprising a bottom (4) and optionally a peripheral wall (2) and / or at least one stud (9); - Forming (E2) a lacquer coating (13) on the bottom (4) of the support member (1), the lacquer coating (13) resting on the bottom (4) of the support member (1) and being optionally delimited on some or all of its sides by a peripheral wall (2) of the support member (1) and / or at least one stud (9); - Piercing and / or machining (in particular trimming and / or contouring) (E3) the lacquer coating (13) as well as the bottom (4) of the support member (1) in a single operation by means of a laser, in particular a femtosecond laser, in order to form a continuous opening (15) passing through the entire thickness of the lacquer coating (13) and all or part of the thickness of the bottom (4) of the support member (1) and / or in order to form a cut-out in the lacquer coating (13) and in the bottom (4) of the support member (1).

Description

[0001] Manufacturing process for a lacquered watch component

[0002] The invention relates to a method for manufacturing a watch component, in particular a dial. It also relates to a watch component itself obtained by implementing such a method. Finally, the invention also relates to a timepiece, in particular a watch, for example a wristwatch, comprising such a watch component.

[0003] When creating a watch component, such as a dial, it is well known that the surface must be treated to meet very high functional and aesthetic standards. This is achieved by using lacquered surfaces, onto which decorative and / or functional elements are added. However, existing manufacturing processes for such lacquered components are unsatisfactory because they do not easily achieve the requirement of a visually perfect lacquer finish—for example, without chips, cracks, or discontinuities—while also incorporating functional and decorative elements. The result is therefore often imperfect and / or obtained through a complex process.

[0004] Thus, one object of the invention is to propose a solution for manufacturing a lacquered watch component in a simple and efficient manner.

[0005] To this end, the manufacturing process for a watch component is characterized in that it comprises the following steps:

[0006] Provide a support including a base and optionally a peripheral wall and / or at least one support block;

[0007] Form a lacquer coating on the base of the support, this lacquer coating resting on the base of the support and optionally delimited on all or part of its sides by a peripheral wall of the support and / or at least one stud and / or at least one partition;

[0008] Drilling and / or machining (including contouring and / or bypassing) the lacquer coating and the substrate background in a single operation using a laser, including a femtosecond laser, to form a continuous opening through the entire thickness of the lacquer coating and all or part of the thickness of the substrate background and / or to form a cutout in the lacquer coating and the substrate background.

[0009] The invention also relates to a watch component comprising a support, including a base and optionally a peripheral wall, and a lacquer coating, this lacquer coating resting on the base of the support and being optionally delimited on all or part of its sides by a peripheral wall of the support, characterized in that it includes a continuous opening or a cutout passing through the lacquer coating and at least part of the base of the support.

[0010] The invention is more precisely defined by the claims.

[0011] These objects, features and advantages of the present invention will be described in detail in the following description of particular embodiments, given by way of non-limiting example, in relation to the accompanying figures, among which:

[0012] Figure 1 schematically represents a cross-sectional view of a watch component during a first step of a first variant of a manufacturing process for the watch component according to a first embodiment of the invention.

[0013] Figure 2 schematically represents a cross-sectional view of the watch component during a second stage of the manufacturing process of the watch component according to the first variant of the first embodiment of the invention.

[0014] Figure 3 schematically represents a cross-sectional view of the watch component during a third stage of the manufacturing process of the watch component according to the first variant of the first embodiment of the invention.

[0015] Figure 4 schematically represents a cross-sectional view of the watch component during a fourth step of the manufacturing process of the watch component according to the first variant of the first embodiment of the invention. Figures 5 to 8 schematically represent cross-sectional views of a watch component for different steps of a second variant of the manufacturing process of the watch component according to the first embodiment of the invention.

[0016] Figures 9 to 13 schematically represent cross-sectional views of a watch component for different stages of a manufacturing process of the watch component according to a second embodiment of the invention.

[0017] Figures 14 and 15 schematically represent cross-sectional views of a watch component for different stages of a manufacturing process of the watch component according to a first variant of a third embodiment of the invention.

[0018] Figures 16 and 17 schematically represent cross-sectional views of a watch component for different stages of a manufacturing process of the watch component according to a second variant of the third embodiment of the invention.

[0019] To simplify the description, the same references will be used for the same or similar elements across the different embodiments and their variants.

[0020] Figures 1 to 4 illustrate a first variant of a first embodiment of the invention. These figures illustrate a cross-section, for example a longitudinal section, of a watch component according to different stages of its manufacture.

[0021] As illustrated in Figure 1, the manufacturing process comprises a first step consisting of providing E1 with a support 1, comprising a base 4 and a peripheral wall 2 extending from the base 4 in a direction perpendicular to the base. The base 4 and the peripheral wall 2 define a recess 3. This support 1 is advantageously produced by a non-through machining step performed in the support, to form the recess 3 while retaining a peripheral wall.

[0022] 2, in which to apply a lacquer finish. Any other type of application to this support is possible. For example, as an alternative, it is possible to attach metal strips or wires to the flat surface of the base 4 of support 1.

[0023] The substrate is advantageously made of metal or a metal alloy, particularly 18-carat gold alloy, or of technical ceramic, such as a zirconia- or alumina-based technical ceramic, or of sapphire, or of glass. Alternatively, it could be made of any material that withstands the conditions of traditional lacquering. The substrate is advantageously a single, homogeneous piece.

[0024] Figure 2 illustrates a second step in the manufacturing process, which consists of forming E2 a lacquer coating 13 on the base 4 of the support, in the housing

[0025] 3. This lacquer coating 13 therefore rests on the base 4 of the support 1 and is delimited on all or part of its sides by the peripheral wall 2 of the support 1.

[0026] This lacquering step is traditional and can be carried out using any known method. For example, it could be a "cold" lacquer, a "hot" lacquer, or urushi lacquer (Japanese lacquer using the sap of the Toxicodendron (Rhus) vernicifluum tree, urushi in Japanese). Any other type of lacquer (epoxy, acrylic, etc.) or similar material could be used. By similar material, we mean materials that are applied in liquid form and solidify on the finished component. Thus, varnishes, paints, polymeric materials, resins, and zapon are considered similar materials. Therefore, lacquer is likely included in this discussion, as well as any coating or material that can be considered a lacquer.

[0027] The lacquer (or similar materials) used can be transparent, opaque, or partially transparent. It can be any color; for example, it can be loaded with pigments (colored, pearlescent, luminescent, phosphorescent, fluorescent, etc.).

[0028] Cold-applied, hot-applied, or urushi lacquer is generally available in liquid form so that it can be applied, for example, with a brush, by pouring, or by spraying (sometimes requiring dilution). Once the lacquer is applied, the surface is dried to bond the lacquer to the substrate and harden it. Drying takes place at room temperature for cold-applied and urushi lacquers; it is done in an oven for hot-applied lacquers. The temperature and drying time depend on the type of lacquer used and the substrate material. Typically, for colored Berlac lacquer applied to a brass substrate, drying takes 1.5 hours at a temperature gradually increasing to 120°C. After drying, gradual cooling is applied to prevent any risk of cracking.Sometimes, this lacquering step is repeated several times to form multiple superimposed layers and achieve the required thickness and quality of the lacquer coating: drying must occur between each layer. Typically, for colorless Berlac lacquer applied over colored lacquer, drying takes place over several hours at a temperature gradually increasing to 140°C. Alternatively, some lacquers are cured by UV irradiation.

[0029] The thickness corresponds approximately to the height of the peripheral wall 2, in its immediate vicinity. Following these steps, the lacquer has a flat and smooth surface, except near the peripheral wall 2 where the lacquer coating 13 has a convex portion 12 due to the formation of a meniscus. This meniscus creates a convex surface on the lacquer coating, and the overall thickness of the lacquer coating is slightly greater than the height of the peripheral wall 2 in this embodiment. In the figures, the size of the convex portion is exaggerated for visualization. Therefore, in its flat central section, the lacquer coating 13 has a thickness greater than that of the peripheral wall 2.Additional finishing, such as sanding or polishing, can be carried out to obtain the desired texture and gloss, and possibly smooth the domed portion 12, but such finishing steps are not mandatory according to the invention.

[0030] Thus, the material is applied in liquid form. Advantageously, the material solidifies by drying at room temperature, or with slight heating (temperature below 150°C, or even below 100°C), or by UV irradiation. Alternatively, it can be in powder form and mixed with a liquid for this shaping step at room temperature.

[0031] Once applied in liquid form, the material solidifies onto the finished component. Advantageously, the material solidifies by drying at room temperature or with slight heating (below 150°C, or even below 100°C). Alternatively, it may require heating to a higher temperature.

[0032] The manufacturing process then involves a third step consisting of drilling E3 through the lacquer coating 13 and the base 4 of the support using a laser, in particular a femtosecond laser. This step is performed in a single operation and creates a continuous opening 15 through the entire thickness of the lacquer coating 13, except for a peripheral wall 2 of the support, or even a stud or partition, and through the entire thickness of the base 4 of the support 1, according to this first embodiment. According to an alternative embodiment not shown, the opening 15 might not completely penetrate the base 4 of the support 1, and might instead form a blind hole in this base 4, in line with the through-hole in the lacquer coating 13.Figure 3 represents the result obtained by this step E3, on which the resulting watch component 10 therefore includes a visible lacquered surface 14, formed by the lacquer coating 13, having an opening 15 which extends over the entire thickness of the lacquer coating 13 and also over the entire thickness of the base 4 of the support, and therefore finally over the entire thickness of the watch component 10.

[0033] In this first embodiment, the manufacturing process includes an additional step consisting of attaching E4 an added element 6 to the opening 15. This added element 6 may be a decorative fitting. Alternatively, it may, for example, be an index, a bezel, or a counter.

[0034] The attachment of the added element 6 can be achieved by any means, for example, by riveting, gluing, or welding. According to the embodiment shown in Figure 4, the added element 6 comprises a head 7 positioned at the level of the visible surface 14 of the lacquer coating and also includes a foot 8 extending into the opening 15. In this embodiment, the foot 8 passes through the entire opening 15 and extends beyond the base 4 of the support, for riveting to the back of the dial. In an alternative (not shown), the foot 8 may not extend over the entire length of the opening 15. It therefore extends at least partially into the opening 15. The opening 15 is thus drilled to accommodate the foot 8. For a surface-mounted foot, the opening 15 can be drilled and have a cylindrical shape with a constant cross-section between 0.15 mm and 1.2 mm in diameter, for example, 0.18 mm in diameter.

[0035] As a note, the head 7 comprises a flat surface that rests on a flat surface of the visible surface 14 of the lacquered coating 13. To achieve this, the opening 15 is made in a flat, smooth portion of the lacquer, that is, outside the convex portion 12 near the peripheral wall 2, so that the entire head rests on a flat surface. Alternatively, an opening can be made in the lacquered coating, sized so that the head 7 is housed there totally or partially: for example, the visible part of the head can be made to be on the same plane as the visible surface 14 of the lacquered coating 13. The opening can have a variable cross-section, with one dimension adapted to receive the head 7, and another smaller dimension adapted to receive the base 8.

[0036] Figure 4 thus represents a finished watch component 10.

[0037] Figures 5 to 8 illustrate a second variant of the first embodiment of the invention.

[0038] This example differs in that the support 1 is limited to the base 4. As shown in Figure 5, this base 4 is temporarily encircled by a removable band that forms a temporary peripheral wall 2 around the perimeter of the base 4, creating a recess 3 for the lacquering process. Indeed, during the lacquering stage, the lacquer is in liquid form before drying. The peripheral wall thus allows the lacquer to adhere to the base 4. After the lacquering is complete, the band is removed, as shown in Figures 7 and 8. This design therefore relies on lacquering using a molding technique. More generally, any removable partition can be used.

[0039] In an alternative not shown, the same result could be achieved by a step consisting of machining, in particular contouring or bypassing, the perimeter of the support 1 according to the first embodiment, preferably using a laser, so as to remove the peripheral wall 2.

[0040] According to another variant not shown, the lacquering could be carried out without a side wall, directly onto the base 4, for example by spraying. In such a variant, a supplementary laser machining sub-step, for example laser trimming or laser contouring, could be used to create a clean edge for the component, particularly the edge of the lacquer coating 13.

[0041] According to another, unshown, variant, the step of drilling E3 through the lacquer coating 13 and the base 4 of the support to create the opening could be replaced by a step of machining E3 through the lacquer coating 13 and the base 4 of the support, in cases where larger openings than those mentioned previously are desired. Drilling is distinguished from other machining operations (including trimming, contouring, etc.) due to the smaller size of the resulting opening. Note that "contouring" refers to machining that progressively removes material, while "trimming" refers to cutting.

[0042] The first embodiment has been described with a single housing 3 delimited by a peripheral wall 2. However, the invention can be implemented on a support comprising several housings, each being delimited by a peripheral wall 2. This therefore applies to a partitioned support, comprising several housings receiving different lacquer coatings.

[0043] Figures 9 to 13 illustrate a second embodiment of the invention, particularly suited to a situation in which a large opening is desired, notably larger than those described previously in relation to figures 1 to 4, for example to fix a kitten.

[0044] Figure 9, like Figure 1, represents a first step in the manufacturing process, consisting of equipping E1 with a support 1, comprising a base 4 and a peripheral wall 2. Unlike Figure 1, this step retains a locating pin 9 positioned where the opening is desired. This locating pin 9 has a height approximately equal to the peripheral wall, according to the embodiment shown, in the direction perpendicular to the base 4. In all cases, the dimension of this locating pin 9 in a plane parallel to the base 4 is chosen to be smaller than the cross-section of the added element. The support 1 thus comprises a recess 3 delimited by the base 4, the peripheral wall 2, and the locating pin 9.

[0045] Figure 10 represents the second step which consists of forming E2 a lacquer coating 13 on the bottom 4 of the support, in the housing 3. This lacquer coating 13 rests on the bottom 4 of the support 1 and is delimited on all or part of its sides by the peripheral wall 2 of the support 1, as well as by the stud 9. As a note, the lacquer coating 13 may have convex portions near the walls, as in the first embodiment.

[0046] The manufacturing process then includes a third step consisting of creating an opening 15. However, this second embodiment differs from the first embodiment in that this step includes the following two sub-steps:

[0047] The first substep consists of drilling a preliminary opening 17 (E31) in the stud 9, as well as in all or part of the thickness of the base 4. This substep is carried out only in the substrate material 1, without directly touching the lacquer coating 13. It can therefore be performed in a conventional manner, with ease and less risk than when working on the lacquer itself. Thus, this substep of drilling a preliminary opening 17 (E31) can be carried out using a laser, but also, alternatively, by any other conventional mechanical means for drilling the substrate material 1. The size of the preliminary opening 17 is smaller than that of the stud 9, so that at the end of this substep, shown in Figure 11, a portion of the stud 9 remains in contact with the lacquer, which is therefore not affected by this substep.

[0048] The second substep finalizes the opening 15 from the initial opening 17 and acts on the lacquer coating 13. According to this second embodiment, this second substep consists of machining (here, contouring) E32 with a laser to remove the residual material from the block 9 until it disappears completely, and then progressively machining (here, contouring) the lacquer to widen the opening until the final opening 15 is reached, having the desired dimensions and shape to receive the kitten's foot. The result is illustrated in Figure 12, which corresponds to Figures 3 and 8 of the first embodiment but with a larger opening 15. As mentioned previously, contouring is a machining process that involves progressively removing material. Note that this second embodiment is performed starting from a block 9.The same principle could be applied directly to a partition wall of the support, for example separating two housings each filled with a lacquer coating.

[0049] Finally, the manufacturing process includes a fourth step consisting of attaching an added element 6 (E4) to the opening 15. This added element 6 may be a chaton. In this embodiment, it is riveted to the back of the dial. Alternatively, it could be glued or welded, or attached by any other means. Figure 13 shows the completed watch component 10.

[0050] Figures 14 to 17 illustrate a third embodiment of the invention. Figure 14 shows the watch component 10 obtained after making an opening 15, which can be formed by direct machining or by the same process as the second embodiment of the invention.

[0051] Figure 15 shows the watch component 10 after a fourth step in the process, which consists of attaching a separate element 6. In this embodiment, the separate element 6 is attached from the side opposite the lacquer coating 13, at the level of the opening 15. According to the first variant of this third embodiment, it is simply attached under the base 4 of the support, at the level of the through opening 15, so that it is visible through this opening from the visible face 14 of the lacquer coating 13. The very clean "section profile" of the watch component, i.e., of both the lacquer coating 13 and the base 4 of the support 1, allows for a very attractive finish of the assembly. According to one embodiment, this separate element 6 can be a counter. It can be secured according to the instructions in document EP3712713A1.

[0052] Figures 16 and 17 illustrate a second variant of the third embodiment of the invention.

[0053] Figure 16 corresponds to Figure 14, after carrying out an additional sub-step consisting of making a counterbore 18 from the face of the bottom 4 opposite the lacquer coating 13, at the level of the opening 15.

[0054] Figure 17 shows the watch component 10 obtained by this second variant, after attaching an added element 6 to the counterbore 18. This added element can be visible through the lacquer or on the case back 4, depending on the depth of the counterbore, so that two different finishes are possible. This added element can also be a counter.

[0055] All the embodiments described above could be combined, allowing an opening to be created in various ways, and in all cases by a step consisting of drilling and / or machining (in particular cutting and / or contouring) E3 at least a portion of the lacquer coating and at least a portion of the substrate using a laser, in a single operation. This step can be used to create an opening within a lacquered substrate, as described in detail, or to cut a lacquered substrate, particularly around its perimeter, as described, but more generally to perform any cut (for example, by contouring). The invention has been described with the creation of an opening or a cut, but it can naturally be implemented to create several openings and / or several cuts.

[0056] The drilling and / or machining (including cutting and / or contouring) step E3 can be performed starting from the front face of the component, i.e., the lacquered face, and then continuing into the substrate until all or part of the substrate is penetrated. Alternatively, the drilling and / or machining (including cutting and / or contouring) step E3 can be performed starting from the back face of the component, i.e., the substrate, and then continuing towards the lacquered face until all or part of the lacquer is penetrated. Through or blind openings can be retained as such and contribute to the final aesthetic of the component. Alternatively, they can be used to install the base of an add-on element, or all or part of an add-on element. Alternatively, blind openings can be filled, totally or partially, with another material, such as lacquer or varnish.

[0057] Lacquer is highly sensitive to uncontrolled heat, which can lead to melting, deformation, changes in color and / or appearance, and / or damage such as bubble formation, discoloration, burn marks, swelling, and / or creep. Therefore, one might expect that laser machining would damage lacquer and be an unsuitable process for this type of coating.

[0058] The technical problem is exacerbated when machining a two-material stack consisting of a lacquered substrate. This is because there is both a difference in how these different materials react to the laser and a difference in their coefficients of thermal expansion. For example, if the substrate is metal, it is advantageous to choose laser parameters that allow the metal to be machined while preventing it from expanding. Since its coefficient of thermal expansion differs from that of the lacquer, there is a risk of generating stress at the interface between the metal and the lacquer, which could cause the lacquer to detach, melt, and / or deteriorate. For these reasons, it is usually chosen to perform laser machining of two different materials with laser parameters specific to each, in two separate operations.Surprisingly, the invention has discovered that a femtosecond laser allows both the ablation of the lacquer and the substrate without inducing defects such as melted areas.

[0059] As a non-limiting example, the laser used could be a femtosecond laser in the infrared (IR), generating pulses with a wavelength of 1030 nm. More specifically, it could be a 20 W source delivering 40 pJ of energy at a frequency of 500 kHz, with a pulse duration of approximately 300 fs. The fluence at the target in this example is 13.5 J / cm². 2(for example, for a beam diameter of 19.5 µm). In the invention, the laser passes through both the lacquer and the substrate in a single operation, i.e., with the same equipment (without changing the machining method), and without needing to reposition the component between the lacquer and substrate processing. Advantageously, the same set of laser settings can even be developed to process both the lacquer and the substrate. Alternatively, however, it could be a single operation with the same laser, whose parameters are changed between the lacquer and the substrate to optimize the penetration through both (for example, to reduce machining time).

[0060] In the examples presented, a scanning technique can be used, which creates a positive draft angle of approximately 10°. To reduce or even eliminate this draft angle, a drilling head or a precession system can be used; the latter also has the advantage of producing a hole or cut with zero or even negative draft angle. Beyond the examples described, the laser can be an ultrashort pulse laser with durations of less than 10 ps, ​​advantageously less than 1 ps, or even less than 500 femtoseconds. It can typically be a femtosecond or picosecond laser. The laser wavelength can be between 300 nm and 1100 nm, advantageously 1030 nm, 515 nm, or 343 nm. The energy per pulse at the focal point is advantageously less than 1 mJ, or even less than 0.5 mJ, or even less than 0.3 mJ, or even less than 0.1 mJ, or even less than 0.05 mJ.The beam diameter is advantageously less than or equal to 50 pm, or even less than or equal to 30 pm, or even less than or equal to 15 pm. The pulse frequency is advantageously less than or equal to 2 MHz, or even less than or equal to 1 MHz, or even less than or equal to 500 kHz, or even less than or equal to 100 kHz. The parameters depend on the apertures to be created and the materials to be etched.

[0061] The invention has been described with examples including the attachment of an added element to an opening. However, the invention can also simply allow for cutting / trimming a lacquered support of a watch component, and / or for viewing an element through a lacquered support of a watch component by creating an opening or a cutout.

[0062] Thus, the invention relates more generally to a method for manufacturing a watch component, characterized in that it comprises the following steps:

[0063] Equip E1 with a support 1 comprising a base 4 and optionally a peripheral wall 2 and one or more pads 9;

[0064] Former E2 a lacquer coating 13 on the bottom 4 of the support 1, this lacquer coating 13 resting on the bottom 4 of the support 1 and being optionally delimited on all or part of its sides by a peripheral wall 2 and / or at least one stud 9 of the support 1;

[0065] Drilling and / or machining (in particular contouring and / or bypassing) E3 the lacquer coating 13 and the base 4 of the support 1 in a single operation using a laser, in particular a femtosecond laser, to form a continuous opening 15 through the entire thickness of the lacquer coating and all or part of the thickness of the base 4 of the support 1 or to form a cutout of the lacquer coating 13 and the base 4 of the support 1.

[0066] The invention also relates to a watch component obtained by this manufacturing process. In the context of this invention, the watch component may be a watch dial, a bezel disc, a bezel, a case, or any other lacquered watch component. It may be flat, even domed (like some dials), frustoconical in shape (like some glasses or bezel discs), or of any other shape.

[0067] The watch component includes a base 4, and optionally a peripheral wall 2, and a lacquer coating 13, this lacquer coating 13 resting on the base 4 and being optionally delimited on all or part of its sides by a peripheral wall 2. The watch component includes a continuous opening 15 or a cutout passing through the lacquer coating 13 and at least part of the base 4. The continuous opening 15 advantageously passes through the entire thickness of the lacquer coating 13, outside a peripheral wall 2 of the support, outside a stud and outside a partition.

[0068] The thickness of the lacquer coating 13 is advantageously between 0.10 mm and 0.40 mm, for example 0.25 mm. The base of the support has, for example, a thickness of 0.5 mm, the watch component thus having an overall thickness of around 0.75 mm.

[0069] More generally, the thickness of the support (especially the background) is between 0.40 mm and 1.5 mm, particularly when this support represents a dial, or even can go beyond, up to 3 mm, or even up to 5 mm when the support represents a watch bezel, or even up to 10 mm, or even up to 20 mm, when the support represents a watch case.

[0070] Similarly, several lacquer thicknesses are possible. The lacquer thickness is advantageously greater than or equal to 0.10 mm, or even greater than or equal to 0.2 mm, or greater than or equal to 0.3 mm and / or less than or equal to 1.0 mm, or even less than or equal to 0.50 mm, or even less than or equal to 0.40 mm. The lacquer thickness is advantageously within this range of values ​​and can therefore differ from one component to another or from one location to another within the component (for example, due to recesses of different depths; or because the lacquering is carried out without partitions, so that the lacquer thickness is not constant across the entire component).

[0071] In several embodiments shown, the opening has a constant cross-section. Alternatively, a variable cross-section can be implemented in all embodiments. For example, a trapezoidal opening with an angle of less than 15°, preferably less than 10°, can be applied with a constant slope, creating a draft angle. Its role is functional; it allows, for example, guiding the base of an attached element or attaching it using a dovetail joint.Alternatively, a variable cross-section can correspond to different functional and / or decorative parts of the component: for example, laser machining can start from the back face of the component, to make a counterbore in the support, then an opening with a diameter smaller than the counterbore, passing through the rest of the support and the lacquered coating; for example again, laser machining can start from the back face of the component, to make a counterbore in the support and part of the lacquered coating, then an opening with a diameter smaller than the counterbore, passing through the rest of the lacquered coating.

[0072] For a kitten, the opening 15 can be made by machining rather than drilling, so as to be able to fit the foot of the kitten, which can have an oblong shape and measure 1.2 mm wide and 2 mm long.

[0073] To fix added elements such as a window or a counter to a dial, a machining can be done to receive this element; typically, the opening can be rectangular or oblong; it can fit into a cylinder measuring more than 0.20 mm in diameter, for example between 0.20 mm and 40 mm in diameter; in practice, there is no upper limit to the size and shape of the opening or cut made in the watch component.

[0074] The watch component may include an added element, fixed to the watch component at the level of said opening. This added element may be, for example, an index, an applique, a chaton, a counter, or a decorative element. Alternatively, any type of added element is possible: it may be lacquered, enameled, decorated with an ornamental stone or mother-of-pearl, coated with a finish deposited, for example, by electroplating, PVD (Physical Vapor Deposition), CVD (Chemical Vapor Deposition), ALD (Atomic Layer Deposition), or PLD (Pulsed Laser Deposition). For example, an added counter (whose shape is that of the counterbore 18 in which it will be positioned) can be prepared and coated with a layer of lacquer 6', which is machined (here contoured) to the diameter of the opening 15 in which it will be housed. In other words, at least part of the lacquer layer 6' of the added element 6 may be located in the opening 15 and outside the counterbore 18.One such embodiment is illustrated in Figure 17, where the added element 6 is a counter placed in a counterbore 18, covered with a layer of lacquer 6' partially inserted in the opening 15 above the counterbore 18, allowing the surface of this layer of lacquer 6' to be recessed, in hollow, relative to the visible surface 14 of the lacquer coating 13 of the watch component.

[0075] The invention fulfills the intended purpose and more generally offers the following advantages:

[0076] - The added elements are placed in an area without a wall, so that they are positioned in an area where the lacquer is flat and smooth on the surface of the dial, without a meniscus due to the proximity of a wall;

[0077] - The surface of the lacquer coating is smooth without needing to be polished in the areas where the opening is planned (thanks to the absence of partitions); therefore, it is not necessary to add a polishing step before creating an opening; - It is possible to choose applied elements forming lacquered decorations, with different appearances depending on their position on the dial plate. There can be lacquered areas with a taut / smooth appearance, which coexist with areas with a convex appearance (near a partition), which is not the case if the lacquer coating is polished after application (it would then be smooth over its entire surface, eliminating any convex areas);

[0078] - Performing the opening in a single operation avoids the errors that would be obtained if two separate operations were implemented, respectively for the lacquer and the support, due to inaccuracies during indexing;

[0079] - Furthermore, the invention comes into play when the watch component is almost finished, which allows for the personalization of added elements such as appliques and indices in the final stage of the manufacturing process. The manufacturing processes for the different models of watch components, such as dials, therefore share common steps up to the personalization stage, which comes at the end of the chain, which is very advantageous;

[0080] The laser cutting or opening process produces a remarkably clean surface, meaning no chips in the lacquer or cracks, and across the entire thickness of the watch component. Surprisingly, using a laser allows for drilling, machining, contouring, and shaping both the lacquer and its substrate in a single step, even though the materials they are made of have very different compositions and mechanical properties.

Claims

DEMANDS:

1. A method for manufacturing a watch component (10), characterized in that it comprises the following steps: Provide (E1) a support (1) comprising a base (4) and optionally a peripheral wall (2) and / or at least one stud (9); Form (E2) a coating of lacquer (13) or similar material on the base (4) of the support (1), this coating of lacquer (13) resting on the base (4) of the support (1) and being optionally delimited on all or part of its sides by a peripheral wall (2) of the support (1) and / or at least one stud (9); Drilling and / or machining (in particular contouring and / or bypassing) (E3) the lacquer coating (13) and the base (4) of the support (1) in a single operation using a laser, in particular a femtosecond laser, to form a continuous opening (15) through the entire thickness of the lacquer coating (13) and all or part of the thickness of the base (4) of the support (1) and / or to form a cutout in the lacquer coating (13) and the base (4) of the support (1).

2. Method of manufacturing a watch component according to the preceding claim, characterized in that the step of drilling and / or machining (E3) includes the use of the same laser continuously, optionally without changing the laser parameters, to form the opening (15) or the cut both in the lacquer coating (13) and in the bottom (4) of the support (1).

3. Method of manufacturing a watch component according to one of the preceding claims, characterized in that the step consisting of drilling and / or machining (E3) includes making an opening (15) on a flat part of the lacquer coating (13) outside a peripheral wall (2) of the support (1).

4. A method for manufacturing a watch component according to any one of the preceding claims, characterized in that the support (1) is made of metal or alloy metallic, especially gold alloy, or technical ceramic, such as zirconia or alumina-based technical ceramic, or sapphire, or glass.

5. Method for manufacturing a watch component according to any one of the preceding claims, characterized in that said laser of the drilling and / or machining step (E3) is an ultrashort pulse laser of durations less than 10 ps, ​​or even less than 1 ps, or even less than 500 fs, of wavelength between 300 nm and 1100 nm, of energy per pulse less than 1 mJ, or even less than 0.5 mJ, or even less than 0.3 mJ, or even less than 0.1 mJ, or even less than 0.05 mJ.

6. A method for manufacturing a watch component according to one of the preceding claims, characterized in that the step of drilling and / or machining (E3) produces an opening of constant cross-section over its entire length through the thickness of the watch component, in particular a cylindrical opening, and / or an opening of variable cross-section through the thickness of the watch component, in particular an opening with a trapezoidal cross-section, in particular with an angle of less than 15°, preferably less than 10°.

7. A method for manufacturing a watch component according to any one of the preceding claims, wherein the step of providing (E1) a support forming a pad (9) or a partition extending from the base (4) over a thickness greater than or equal to the thickness of the lacquer coating (13) to be deposited, and wherein the step of drilling and / or machining (E3) is characterized in that it comprises a substep of drilling (E31) the pad (9) or the partition forming a rough opening (17) of said opening (15) within said pad (9) or said partition, then a substep of bypassing (E32) the lacquer coating and / or the lacquer coating and the base (4) of the support in the rough opening (17) until all the material of the pad (9) or the partition is removed and the opening (15) is formed at least within the lacquer coating (13).

8. A method for manufacturing a watch component according to any one of the preceding claims, characterized in that it comprises an additional step consisting of fixing (E4) an added element (6) at the level of said opening (15), in particular by riveting or gluing or welding, the added element (6) comprising a head (7) positioned at the level of the visible surface (14) of the lacquer coating (13) and comprising a foot (8) extending at least partially into said opening (15), and / or the added element (6) being secured under the lower surface of the bottom (4) of the support at the level of the opening (15) or in a counterbore (18) formed in the bottom (4) of the support (1) and optionally in the opening (15) within the lacquer coating (13).

9. Watch component (10) comprising a support (1), including a base (4) and optionally a peripheral wall (2), and a lacquer coating (13), this lacquer coating (13) resting on the base (4) of the support (1) and being optionally delimited on all or part of its sides by a peripheral wall (2) of the support (1), characterized in that it includes a continuous opening (15) or a cutout passing through the lacquer coating (13) and at least part through the base (4) of the support (1).

10. Watch component according to the preceding claim, characterized in that the opening is a cylindrical opening with a diameter between 0.15 mm and 1.2 mm, or less than or equal to 0.50 mm, or less than or equal to 0.20 mm, or an opening inscribed in a cylinder with a diameter between 0.20 mm and 40 mm, or less than or equal to 10 mm, or less than or equal to 5 mm, and / or in that the opening has a constant or variable cross-section over its entire length, and / or in that the watch component has a thickness between 0.40 mm and 1.5 mm, or less than or equal to 1.5 mm, or less than or equal to 3 mm, or less than or equal to 5 mm, or less than or equal to 10 mm, or less than or equal to 20 mm, and / or in that the thickness of the lacquer is greater than or equal to 0.10 mm, or greater than or equal to 0.20 mm, or greater than or equal to 0.30 mm and / or in that the thickness of Iaque is less than or equal to 1.0 mm, or less than or equal to 0.50 mm, or less than or equal to 0.40 mm. 22 11. Watch component according to claim 9 or 10, characterized in that the support (1) is made of metal or metal alloy, in particular gold alloy, or technical ceramic, such as a technical ceramic based on zirconia or alumina, or sapphire, or glass.

12. Watch component according to any one of claims 9 to 11, characterized in that it comprises an added element (6), such as an index, an applique, a chaton, a counter, or a decorative element, fixed to the watch component at the level of said opening.

13. Watch component according to the preceding claim, characterized in that the added element (6) comprises a head (7) resting on the visible surface (14) of the lacquer coating (13) and a foot (8) extending into the opening (15), optionally secured at the base (4) of the support (1), or in that the added element (6) is fixed under the base (4) of the support (1) at the level of said opening (15) or in a counterbore (18) so as to be visible by the opposite visible surface of the watch component (10).

14. Watch component according to any one of claims 9 to 13, characterized in that it comprises a visible surface (14) of the unpolished lacquer coating (13) comprising a first domed portion (12) in the vicinity of a peripheral wall (2) and a second flat portion further away from the peripheral wall (2), the opening (15) being positioned in said second flat portion.

15. Watch component according to any one of claims 9 to 14, characterized in that it is a watch dial and in that the support (1) is a dial plate, or a bezel, or a bezel disc, or a case.

16. Timepiece, characterized in that it comprises at least one timepiece component according to one of claims 9 to 15.

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