Method for manufacturing metal plating or growth mold

Abstract

The invention relates to a method for manufacturing a mold for electroplating or metal growth of a watch part (31, 32) or a piece of jewelry (31, 32), comprising the steps of: - obtaining at least one base substrate (11), - depositing at least one layer of photosensitive resin (13), - irradiating at least a first portion of the layer of photosensitive resin (13) - characterized: - in that the irradiation of the first portion of said at least one layer of photosensitive resin (13) comprises a step of projecting onto said at least one layer of photosensitive resin (13) at least one first irradiation pattern (PM) corresponding to at least a first portion of a first watch or jewelry part (31, 32).

Description

Technical field of the invention

[0001] The present invention relates generally to the manufacture of electroplating or metal growth molds which are subsequently used to manufacture watch or jewelry components by electroplating, electrodeposition, metal growth, catalytic or autocatalytic growth. Such molds are typically manufactured using processes that employ photolithography to irradiate a photosensitive resin and then create an impression in the resin. State of the art

[0002] It is known in the processes of manufacturing electroplating or metal growth molds to interpose a mask (typically a transparent plate coated with a metallic film and then etched) between a light source and the photosensitive resin. However, such a mask requires specific manufacturing, and a new mask must be used each time a mold is to be made for a new watch or jewelry component, which obviously limits the flexibility of the manufacturing process and / or increases production costs.

[0003] It is also known in the prior art WO 2023 / 012035 A1 to be able to irradiate photosensitive resin with a laser beam or an electron beam. However, this method requires a significant amount of time to fully irradiate the desired surface of the photosensitive resin. Furthermore, once the photosensitive resin has been irradiated, it can be developed in a specific developing solvent, thus forming impressions and edges in the resin. It may be observed that the edges of the impressions do not perfectly conform to the desired geometry (deviations in perpendicularity, flatness, etc., may be present), so the geometry of watch or jewelry components can be negatively affected. Description of the invention

[0004] One object of the present invention is to address the disadvantages of the prior art mentioned above and in particular, first of all, to propose a method for manufacturing a mold for electroplating or metal growth of a watch part or a piece of jewelry which is flexible, and / or which is fast, and / or which allows for changing the manufacturing reference without significant additional costs, and / or which allows for the subsequent manufacture of a watch part or a piece of jewelry with high precision.

[0005] To this end, a first aspect of the invention relates to a method for manufacturing a mold for electroplating or metal growth of at least one watch component or at least one piece of jewelry, comprising the steps of: to provide at least one base substrate, to deposit at least one layer of photosensitive resin on said at least one base substrate, to irradiate at least a first portion, and for example only a part, of said at least one layer of photosensitive resin characterized: in that the irradiation of said at least a first portion of said at least one layer of photosensitive resin includes a step consisting of projecting onto said at least one layer of photosensitive resin at least a first irradiation pattern corresponding to at least a first portion of a first piece of watchmaking or jewelry. According to one embodiment, the irradiation of the first irradiation pattern can be free from masking and / or the use of a mask interposed between an irradiation source and the resin.

[0006] According to the implementation described above, irradiation according to the first pattern is performed "all at once," meaning that an entire portion of the photosensitive resin is irradiated simultaneously. Thus, the irradiation takes less time than when a beam or ray is moved to irradiate at least a first portion. In other words, the first projected pattern has a larger surface area than a beam of light or electrons, and the irradiation is performed in a single pass. It should be noted that irradiation according to the first pattern can be performed without the use of a transparent physical mask with an opaque, perforated layer (traditionally used in lithography) interposed between the light source and the photosensitive resin.In other words, irradiation according to the first pattern can be free of a step of displacement or positioning or creation of a mask (typically made in a panel or plate, such as a transparent plate (glass, quartz) coated and engraved with the pattern to be irradiated).

[0007] The manufacturing process can be defined by the following characteristics, taken individually or in combination.

[0008] According to one embodiment, the manufacturing process comprises, after irradiating the first portion of at least one layer of photosensitive resin, irradiating a second portion of said at least one layer of photosensitive resin by projecting onto said at least one layer of photosensitive resin a second irradiation pattern corresponding, for example, to a second portion of at least one first watch or jewelry component, or preferably to at least one second watch or jewelry component. According to this embodiment, it is proposed to modify the irradiation pattern between the first and second irradiations, thereby increasing the flexibility of the process.

[0009] In one embodiment, the first irradiation pattern and / or the second irradiation pattern has a contour with at least one edge, and / or at least one straight portion, and / or at least one projection, and / or at least one recessed shape relative to the rest of the contour. In other words, the first irradiation pattern and / or the second irradiation pattern has a complex shape, contour, or perimeter that corresponds to at least a portion of the shape, contour, or perimeter of the first or second timepiece or piece of jewelry, respectively. In other words, the first irradiation pattern and / or the second irradiation pattern is not formed by or created with a spot or point of light from a collimated or focused irradiation beam that moves to irradiate the photosensitive resin.According to one embodiment, the first irradiation pattern and / or the second irradiation pattern are not formed by a writing process, nor by a light beam that travels through the resin layer.

[0010] According to one embodiment, the irradiation of the first irradiation pattern and / or the irradiation of the second irradiation pattern is free of relative displacement between the base substrate and an irradiation ray.

[0011] In one embodiment, the irradiation of the first irradiation pattern comprises the simultaneous irradiation of several irradiated surfaces separated by at least one unirradiated surface. In another embodiment, the irradiation of the second irradiation pattern comprises the simultaneous irradiation of several irradiated surfaces separated by at least one unirradiated surface. In other words, the first and / or second irradiation pattern comprises or is formed by areas irradiated simultaneously or simultaneously and unirradiated areas. A writing beam, from a known direct writing process, cannot simultaneously irradiate several areas separated by unirradiated areas.

[0012] In one embodiment, the first portion of said at least one layer of photosensitive resin and the second portion of said at least one layer of photosensitive resin are distinct, for example separated by a predetermined distance or arranged on two different base substrates or arranged on two different layers of photosensitive resin. This makes it possible to form distinct patterns for distinct impressions intended to manufacture distinct parts.

[0013] In one embodiment, the manufacturing process includes a step, preferably performed between the irradiation of the first portion and the irradiation of the second portion, consisting of imposing a relative displacement between an irradiation source and said at least one base substrate or said at least one layer of photosensitive resin. Once the first portion has been irradiated, the base substrate and / or the photosensitive resin is displaced in order to irradiate the second portion.

[0014] In one embodiment, the first portion of said at least one layer of photosensitive resin and the second portion of said at least one layer of photosensitive resin are adjacent or partially overlapping. It is thus possible to irradiate the same portion of resin or adjacent portions of resin differently or sequentially.

[0015] According to one embodiment, the projection of the second irradiation pattern includes (or leads to) the irradiation of at least a part of said at least one layer of the photosensitive resin already irradiated, and includes the irradiation of at least a part of said at least one layer of the photosensitive resin not already irradiated.

[0016] According to one embodiment: the projection of the first irradiation pattern includes a step of structuring a source irradiation beam to obtain the first irradiation pattern, and / or the projection of the second irradiation pattern includes a step of structuring the source irradiation beam to obtain the second irradiation pattern. The structuring of the source irradiation beam may include initial steps or operations consisting of obtaining: from a source irradiation beam which has source optical characteristics (with for example a source focusing, a source collimation, a source divergence, a source convergence, one or more source irradiation wavelengths, a source irradiation silhouette, a source irradiation perimeter, a source angle of incidence ...), a first irradiation pattern (with for example a first focusing, a first collimation, a first divergence, a first convergence, a first or first irradiation wavelength(s), a first irradiation silhouette, a first irradiation perimeter, a first angle of incidence ...). The structuring of the source irradiation beam may then include second steps or operations consisting of obtaining: from the source irradiation beam which has the source optical characteristics (with for example a source focusing, a source collimation, a source divergence, a source convergence, one or more source irradiation wavelengths, a source irradiation silhouette, a source irradiation perimeter, a source angle of incidence ...), a second irradiation pattern (with for example a second focusing, a second collimation, a second divergence, a second convergence, a second or second irradiation wavelength(s), a second irradiation silhouette, a second irradiation perimeter, a second angle of incidence ...).

[0017] In one embodiment, the first irradiation motif and / or the second irradiation motif is at least part of a silhouette of a watch component, with complex contours (at least a portion of the teeth, at least a peripheral portion of the watch or jewelry component, at least a portion of a bore, etc.). The structuring may include any kind of optical operation to structure the source irradiation beam: reflection on mirrors, movement of mirrors, passage through lenses, movement of lenses, passage through filters, movement of filters, switching on / off / moving certain light sources, etc.

[0018] According to one embodiment, the projection of the first irradiation pattern carried out with first optical parameters (in particular with a first wavelength) is followed by a projection of the first irradiation pattern carried out with second optical parameters (in particular with a second wavelength).

[0019] In one embodiment, the exposure is carried out with a beam comprising several wavelengths. In terms of light energy, the beam is expected to deliver a first percentage of energy at a wavelength of 365 nm, a second percentage at 380 nm, a third percentage at 395 nm, and a fourth percentage at 405 nm. Wavelengths and / or percentages other than those mentioned above can be selected depending on the irradiation depth, substrate thickness, resin type, etc.

[0020] According to one embodiment, the projection of the first irradiation pattern and the projection of the second irradiation pattern are separated by a period of irradiation stoppage.

[0021] According to one embodiment, the projection of the first irradiation pattern and the projection of the second irradiation pattern are carried out one after the other, preferably without a period of interruption of the irradiation.

[0022] According to one embodiment, the projection of the first irradiation pattern and / or the projection of the second irradiation pattern includes the generation of a digital image to be projected.

[0023] In one embodiment, the projection of the first irradiation pattern and / or the projection of the second irradiation pattern includes the use of a light valve and / or a mirror and / or a light modulator and / or a liquid crystal display. In certain variations of this embodiment, an adaptive or dynamic digital mask (e.g., liquid crystals) can be considered to be used to create the first or second irradiation pattern.

[0024] According to one embodiment, the projection of the first irradiation pattern and / or the projection of the second irradiation pattern includes the simultaneous irradiation of a continuous surface area greater than 0.0001 mm², preferably greater than 0.001 mm², preferably greater than 0.1 mm², preferably greater than 0.3 mm², preferably greater than 0.5 mm², preferably greater than 0.7 mm². In other words, the continuous irradiated surface area is greater than that of a spot or point of a moving direct irradiation beam that moves relative to the resin to irradiate it.

[0025] According to one embodiment, the projection of the first irradiation pattern and / or the projection of the second irradiation pattern comprises: The delivery of a first predetermined dose of irradiation energy, for example, to a first depth in the photosensitive resin, followed by an adjustment and / or modification of an irradiation characteristic for the delivery of a second predetermined dose of irradiation energy, for example, to a second depth in the photosensitive resin, performed after the delivery of the first predetermined dose of irradiation energy to the first depth in the photosensitive resin. According to this implementation, several sequential or successive irradiations can be carried out, changing at least one irradiation characteristic so as to specifically irradiate the resin to a particular depth.This allows us to compensate for diffraction, reflection, absorption, and energy distribution phenomena of the light beam (e.g., the Gaussian shape of the laser) within the resin to guarantee a specific geometry (particularly along the direction of irradiation penetration into the resin) of the footprint sides that will be formed after the resin has been developed. In a specific example, it is possible to obtain sides that exhibit precise verticality (within ±1°, for example), even if the resin layer is thick (e.g., more than 300 µm, 400 µm, 500 µm, or 600 µm).

[0026] According to one embodiment, the first predetermined dose of irradiation energy at a first depth in the photosensitive resin and the second predetermined dose of irradiation energy at a second depth in the photosensitive resin are applied sequentially (separately in time) to the same column, the same thickness, or the same area of ​​resin. In other words, the same volume of resin: is irradiated a first time to deliver the first predetermined dose of irradiation energy to a first depth in the photosensitive resin, is irradiated a second time to deliver the second predetermined dose of irradiation energy to a second depth in the photosensitive resin.

[0027] According to one embodiment, the projection of the first irradiation pattern and / or the projection of the second irradiation pattern comprises: a first irradiation phase, an adjustment and / or modification of an irradiation characteristic, such as an adjustment and / or modification of a focus of radiation emitted during irradiation, such as a modification of the relative position of a focal plane of the emitted radiation with respect to an external surface of the photosensitive resin, such as an adjustment and / or modification of a wavelength of radiation emitted during irradiation, such as an adjustment and / or modification of a resolution of radiation emitted during irradiation, such as an adjustment and / or modification of an irradiation power or irradiation energy; a second irradiation phase carried out with the adjusted or modified irradiation characteristic.It is perfectly possible to plan to irradiate the first irradiation pattern several times, and / or the second irradiation pattern (with each time a specific setting to preferentially irradiate a particular depth).

[0028] According to one embodiment, the projection of the first irradiation pattern and / or the projection of the second irradiation pattern comprises: a first irradiation phase carried out with a first resolution, a second irradiation phase carried out with a second resolution.

[0029] In other words, the invention may relate to a method for manufacturing a mold for electroplating or metal growth of a watch or jewelry component, comprising the steps of: to obtain at least one base substrate, to deposit at least one layer of photosensitive resin on said at least one base substrate, to irradiate at least a first portion of said at least one layer of photosensitive resin characterized in that the irradiation (direct, or free from masking) of said at least a first portion of said at least one layer of photosensitive resin comprises: A first irradiation phase is performed with a first resolution, followed by a second irradiation phase with a second resolution. The same direct irradiation machine (without a mask) can be used.

[0030] According to one embodiment: During the first phase of irradiation, a first sub-portion of the first irradiation pattern and / or the second irradiation pattern is irradiated; during the second phase of irradiation, a second sub-portion of the first irradiation pattern and / or the second irradiation pattern is irradiated.

[0031] According to one embodiment: The first sub-portion of the first irradiation pattern and / or the second irradiation pattern: forms a part common to several part references, or forms a non-functional part of the part to be manufactured (i.e., without contact or interaction with other parts of a mechanism, such as an anchor rod, an arm or a gear rim...), or forms a part of a part having dimensions with so-called wide initial tolerances; the second sub-portion of the first irradiation pattern and / or the second irradiation pattern: forms a part specific to a particular part reference, or forms a functional part of the part to be manufactured (i.e., with contact or interaction with other parts of a mechanism, such as a gear tooth, a pulse surface or a pallet locking beak...), or forms a part of a piece having dimensions with second tolerances said to be fine and / or tighter than the first tolerances, or represents an area of ​​at most 50% of the area of ​​the first sub-portion, preferably at most 40% of the area of ​​the first sub-portion, preferably at most 20% of the area of ​​the first sub-portion, preferably at most 10% of the area of ​​the first sub-portion. .

[0032] In one embodiment, at least a portion of the first sub-portion does not overlap with the second sub-portion. In another embodiment, at least a portion of the second sub-portion does not overlap with the first sub-portion. In other words, at least one part of the first and second sub-portions is irradiated only once and / or with a single resolution. However, at least one other portion of the first sub-portion may overlap with another portion of the second sub-portion.

[0033] In one embodiment, the first resolution is lower, weaker, or less precise than the second resolution. In one embodiment, the first resolution is greater than 0.5 µm, preferably greater than 1 µm, preferably greater than 2 µm, preferably greater than 5 µm, preferably greater than 10 µm, preferably greater than 15 µm. In one embodiment, the second resolution is less than 15 µm, preferably less than 10 µm, preferably less than 5 µm, preferably less than 2 µm, preferably less than 1 µm, preferably less than 0.5 µm.

[0034] According to one embodiment: The first resolution ("coarse" or "low resolution") allows for the rapid irradiation of a first sub-portion of the first irradiation pattern and / or the second irradiation pattern, and the second resolution ("fine" or "high resolution") allows for the very precise irradiation of a second sub-portion of the first irradiation pattern and / or the second irradiation pattern.

[0035] In one embodiment, the contours of the part to be manufactured or of a mold can be irradiated at high resolution (for example, with a small or precisely focused light spot). In another embodiment, all contour paths can be scanned by the structured light spot. In yet another embodiment, the interior (between two contour paths) can be irradiated at low resolution (for example, with a spot having a much larger surface area or a less precisely focused spot), in order to irradiate a larger area at once and therefore with lower resolution but more quickly.

[0036] According to one embodiment, the first and second irradiation phases can be reversed. In other words, one can start with "low resolution" irradiation and then perform "high resolution" irradiation, but one can just as easily perform "high resolution" irradiation first and then "low resolution" irradiation.

[0037] According to one embodiment, the first irradiation phase and / or the second irradiation phase is carried out with a light beam of the type light ray, for example focused, or with a light beam structured using micromirrors or a screen.

[0038] According to one embodiment, between the irradiation of the first portion and the irradiation of the second portion, the adjustment and / or modification of the focus of a radiation emitted during the irradiation, is a modification of the relative position of the focal plane of the emitted radiation with respect to an external surface of the photosensitive resin of at least 80 µm, preferably at least 100 µm, preferably at least 125 µm, preferably at least 150 µm, preferably at least 175 µm.

[0039] In one embodiment, the manufacturing process includes at least one step consisting of texturing or developing said at least one layer of photosensitive resin to form at least one mold for creating the timepiece or piece of jewelry. Such texturing may also be called resin development.

[0040] In one embodiment, the first irradiation pattern corresponds to a first watch or jewelry component, and the second irradiation pattern corresponds to a second watch or jewelry component arranged to be coupled or to cooperate with the first watch or jewelry component, respectively. In a preferred embodiment of this variant, the first irradiation pattern is projected onto the same layer of photosensitive resin as the second irradiation pattern, so as to guarantee an identical thickness between the components. This thickness can be within ±10 µm, preferably within ±7 µm. Thus, it can be guaranteed that the first watch or jewelry component will have the same thickness as the second watch or jewelry component.If a grinding step is carried out, the differences in thickness will be less, and the grinding will be faster.

[0041] According to one embodiment, the first or second clockwork component can be a part of a movement or a decorative part, such as a clockwork gear, an escape wheel, an anchor, a clockwork bridge, an index, a hand...

[0042] According to one embodiment, the first piece of jewelry or the second piece of jewelry may be a part of a clasp or a joint of a piece of jewelry, such as for example a bezel, a bolt, a strike plate, a joint hub.

[0043] According to one embodiment, the process, and at least the irradiation of the first or second irradiation motif, is free from a step of setting up / moving / manufacturing a physical mask such as a plate or panel etched to be partially transparent. However, for locations other than the first or second irradiation motif (or even for preliminary or subsequent irradiation including the first or second motif), a step of setting up / moving / manufacturing a physical mask may be required.

[0044] In one embodiment, the process, and at least the irradiation of the first or second irradiation pattern, may be entirely free of the step of projecting and moving an irradiation point or a light beam onto the resin. The process may include a step of projecting and moving an irradiation point or a light beam onto the resin to irradiate only a portion of the resin to be irradiated.

[0045] In one embodiment, the process includes a step of moving, deforming, adjusting, or modifying a contour or surface of the first irradiation pattern to obtain the second irradiation pattern. In one embodiment, the step of moving, deforming, adjusting, or modifying a contour or surface of the first irradiation pattern to obtain the second irradiation pattern is dynamic, continuous, or without interruption of the irradiation.

[0046] According to one embodiment, irradiation can be carried out with UV light rays, visible light rays, infrared rays, electron rays, laser light rays.

[0047] According to one embodiment, the process includes a step, for example preliminary, consisting of depositing a conductive or priming layer, typically on at least one base surface of the base substrate.

[0048] In one embodiment, the process includes a step of depositing at least one additional layer of resin, and a step of irradiating at least a portion of this additional resin, typically according to the implementations described above. The additional resin layer, once irradiated, is typically developed to form impressions or a particular texture.

[0049] According to one embodiment, the resin is of the SU-8 type.

[0050] According to one embodiment, the resin is deposited on a spinning wheel (Spin coating), or in the form of a dry film (laminated layer).

[0051] A second aspect of the invention may relate to a method for manufacturing a timepiece or a piece of jewelry, comprising: the manufacture of an electroplating or metal growth mold according to one of the first aspects, at least one electroplating or metal growth step in the mold to form the watch part or the piece of jewelry.

[0052] According to one embodiment, the watch part or the piece of jewelry can be made of nickel, nickel-phosphorus alloy, gold, and generally any material or metal that can be electrodeposited and / or deposited catalytically.

[0053] In one embodiment, the manufacturing process for a watch or jewelry component includes a step of releasing the watch or jewelry component. This step may involve dissolving or treating / removing the resin forming the mold cavities and / or the base substrate using plasma. Description of the figures

[0054] Other features and advantages of the present invention will become more apparent upon reading the following detailed description of embodiment(s) of the invention given by way of non-limiting example(s) and illustrated by the accompanying drawings, in which: [ fig. 1 ] represents a timepiece that can be manufactured using an electroplating or metal growth mold; [ fig. 2 ] represents a first step in a manufacturing process for an electroplating or metal growth mold by using a basic substrate; [ fig. 3 ] represents a second step in the manufacturing process by depositing a layer of photosensitive resin onto the base substrate; [ fig. 4 ] represents a third step in the manufacturing process by irradiating a first portion of the photosensitive resin layer, according to a first variant; [ fig. 5 ] represents a fourth step in the manufacturing process by irradiating a second portion of the photosensitive resin layer, according to the first variant; [ fig. 6 ] represents a fifth step in the manufacturing process by developing the photosensitive resin layer to obtain a mold for electroplating or metal growth for the manufacture of a watch or jewelry component; [ fig. 7 ] represents the first stage in the manufacture of a watch or jewelry component using the mold of the figure 6 ; fig. 8 ] represents a second stage in the manufacturing of a watch or jewelry component by removing the photosensitive resin from the base substrate; [ fig. 9 ] represents the watch or jewelry components obtained once freed from the base substrate; [ fig. 10 ] represents a first step in a second variant of the irradiation steps of figures 4 And 5 of the manufacturing process; [ fig. 11 ] represents a second step of the second variant of the irradiation steps of figures 4 And 5 of the manufacturing process; [ fig. 12 ] represents a first step in a third variant of the irradiation steps of figures 4 And 5 of the manufacturing process; [ fig. 13 ] represents a second step of the third variant of the irradiation steps of figures 4 And 5 of the manufacturing process. Detailed description of implementation method(s)

[0055] There figure 1 represents an escapement wheel forming a clockwork component that can be manufactured using an electroplating or metal growth mold. Indeed, the escapement wheel of the figure 1 is a thin, flat piece (for example, with a thickness between 80 µm and 500 µm), and can be manufactured by electroplating or metal growth, according to a process generally known as UV-LIGA (a process for manufacturing microstructures by photolithography and electroforming. This process uses an ultraviolet (UV) light source to expose a photoresist, usually a SU-8 resin, to create impressions in which parts can be formed by electrodeposition).

[0056] The exhaust wheel of the figure 1 can typically be made of metal, such as nickel, a nickel-phosphorus alloy, gold... The example of the figure 1 is an escape wheel, but we can plan to manufacture any other watch part, such as an anchor, a watch bridge, an index, a hand... We can also plan to manufacture a piece of jewelry such as a bezel, a part of a clasp or a joint of a piece of jewelry, such as a bolt, a strike plate, a hinge hub...

[0057] There figure 2 This represents the first step in a manufacturing process for an electroplating or metal growth mold, using a base substrate 11 covered with a conductive layer 12. The base substrate 11 is typically a silicon wafer, but any other type of base substrate is acceptable. The conductive layer 12 can be a thin layer of gold deposited by physical vapor deposition (PVD). Alternatively, layer 12 can be a starting layer designed to induce or promote catalytic deposition and growth without an electric deposition current (an "electroless" process).

[0058] There figure 3 This represents a second step in the manufacturing process, involving the deposition of a layer of photosensitive resin 13 onto the base substrate 11 (more specifically, onto the conductive layer 12 of the base substrate 11). For example, SU-8 resin, a negative photosensitive resin commonly used in this field, could be deposited. Deposition could be performed using a spin coating or by depositing a "ready-to-deposit" film. SU-8 resin exhibits a peak absorption or maximum sensitivity in the ultraviolet range, at a wavelength of 365 nm. However, this resin is also reactive at other wavelengths.

[0059] There figure 4 This represents a third step in the manufacturing process by irradiating a first portion of the photosensitive resin layer 13, according to a first variant. In this first variant, an irradiation device 20 is positioned opposite the photosensitive resin layer 13, and a first PM pattern is projected onto the photosensitive resin layer 13, thus irradiating an entire first portion of the photosensitive resin layer 13 in a single pass. The irradiation device 20 typically includes one or more irradiation sources (light-emitting diodes, UV diodes, etc.), optical elements (mirrors, lenses, etc.) to generate a pattern to be projected onto the photosensitive resin.

[0060] Typically, the first PM pattern projected onto the photosensitive resin layer 13 can correspond to the exhaust wheel of the figure 1 to irradiate in one go all the photosensitive resin 13 needed to form an imprint corresponding to the escape wheel of the figure 1 However, it is possible to irradiate only a portion of the part to be formed. In this case, the first PM pattern projected onto the photosensitive resin layer 13 would correspond to only a part of the escape wheel of the figure 1 .

[0061] It can be noted that the irradiation device 20 does not include a mask to be placed between a light source of the irradiation device 20 and the photosensitive resin layer 13. In particular, it can be noted that for this irradiation step of the first portion of resin to the figure 4 no physical mask (a panel or engraved plate to let light through) is used.

[0062] To generate the first PM pattern, the irradiation device 20 is designed to generate an image corresponding to that first pattern. Specifically, the irradiation device 20 can use at least one Grating Light Valve (GLV) and / or at least one Digital Mirror Device (DMD), and / or a light modulator and / or a liquid crystal display. In particular, by specifically controlling at least one Grating Light Valve from a set of several Grating Light Valves and / or at least one mirror from a set of several mirrors, or a light modulator and / or a liquid crystal display, the first pattern can be created.

[0063] There figure 5 represents a fourth step in the manufacturing process by irradiating a second portion of the photosensitive resin layer 13, according to the first variant. Indeed, after irradiating the first portion of the photosensitive resin layer 13, the process includes a step consisting of projecting a second motif DM to irradiate a second portion of the photosensitive resin layer 13, typically to be able to form an impression in the photosensitive resin layer 13 corresponding to a second watch or jewelry piece, different from the first piece corresponding to the first motif PM.

[0064] To this end, to generate the second DM pattern, the irradiation device 20 is designed to generate an image corresponding to the second DM pattern. In particular, at least one light valve from a set of several light valves and / or at least one mirror from a set of several mirrors, or a light modulator and / or a liquid crystal display, can be specifically controlled to create the second DM pattern.

[0065] Thus, by modifying the configuration of the irradiation device 20 dynamically or at least between the stages of figures 4 And 5 The irradiation pattern can be modified to form a first PM pattern or a second DM pattern, each corresponding to a specific part to be manufactured. It is also possible to move the base substrate 11 and / or the irradiation device 20 between the steps of the figures 4 And 5 , to form a first PM motif and a second DM motif that are quite distinct.

[0066] There figure 6 This represents a fifth step in the manufacturing process, developing the photosensitive resin layer 13 to obtain a mold for electroplating or metal growth for the production of a watch or jewelry component. More specifically, the resin may be immersed in a specific developing solvent, and oxygen and CF4 plasma may also be used to remove residues from the developed patterns or impressions.

[0067] There figure 7 represents a first step in the manufacture of a timepiece 31, 32 (or a piece of jewelry) using the mold of the figure 6 Galvanic growth, or catalytic or autocatalytic growth, can be predicted.

[0068] There figure 8 represents a second manufacturing step of a watch part 31, 32 (or a piece of jewelry) by removing the photosensitive resin 13 from the base substrate 11, for example with a CF4 plasma.

[0069] There figure 9 represents the watch parts 31 and 32 (or jewelry) obtained once freed from the base substrate (for example by dissolving the silicon base substrate 11 in a KOH bath, and etching the conductive layer 12).

[0070] There figure 10 represents a first step in a second variant of the irradiation steps of figures 4 And 5 of the manufacturing process. Indeed, in combination or as an alternative to the irradiation steps of figures 4 And 5 We can anticipate the steps involved in: irradiating the photosensitive resin 13 to deliver a first dose of predetermined irradiation energy to a first part of the photosensitive resin 13 located at a first depth P1 in the photosensitive resin 13, after irradiating the first part of the photosensitive resin 13, an adjustment and / or modification of an irradiation characteristic is made, to deliver a second dose of predetermined irradiation energy to a second part of the photosensitive resin 13 located at a second depth P2 in the photosensitive resin 13. The adjustment and / or modification of an irradiation characteristic can be provided either to carry out the irradiation of a complete pattern in one piece, or to carry out the irradiation with a static or dynamic (moving) irradiation beam.

[0071] In concrete terms, the figure 10 represents the irradiation of the first part of the photosensitive resin 13 with first optical parameters: a first focus f1, and / or a first depth of field DoF1, and / or at least a first wavelength λ1, and / or a first irradiation power P1, and / or a first irradiation energy E1, and / or a first irradiation time T1, and / or a first irradiation contour C1... This first configuration allows a first dose of predetermined irradiation energy to be delivered to the first part of the photosensitive resin 13 located at the first depth P1.

[0072] It is understood that the remainder of the column or the thickness of the photosensitive resin 13 is also irradiated. However, the spatial distribution of irradiation energy is not homogeneous throughout the thickness of the resin 13, and this can lead to resin sides, once developed, not exhibiting the desired verticality. It should also be noted that a single exposure does not allow for defining or guaranteeing a desired orientation of the sides (for example, an inclination relative to the vertical). figure 10 ).

[0073] To overcome these drawbacks, the figure 11 represents a second step of the second variant of the irradiation steps of the figures 4 And 5 of the manufacturing process. Specifically, the figure 11 represents the irradiation of the second part of the photosensitive resin 13 with second optical parameters: a second focusing f2, and / or a second depth of field DoF2, and / or at least a second wavelength λ2, and / or a second irradiation power P2, and / or a second irradiation energy E2, and / or a second irradiation time T2, and / or a second irradiation contour C2... This second configuration allows a second predetermined dose of irradiation energy to be delivered to the second part of the photosensitive resin 13 located at the second depth P2. It is understood that the remainder of the column or thickness of photosensitive resin 13 is also irradiated.

[0074] Sequential irradiation of the photosensitive resin 13 at different depths makes it possible to obtain lateral edges of impressions with a very precise orientation relative to the vertical. For example, perfectly vertical edges can be obtained, even at significant thicknesses. An orientation of ±1° relative to the vertical can be guaranteed.

[0075] The stages of figures 10 et 11 These steps are preferably implemented for thick photosensitive resin layers, for example, with a thickness of at least 200 µm, 300 µm, 400 µm, 500 µm, or more. Multiple irradiation passes can be performed to shift, for example, the "optimal" or "maximum" target irradiation depth by at least 150 µm, or 200 µm, between each pass. However, steps 10 and 11 are also feasible for thinner resin layers (e.g., 150 µm) if, for example, a high-resolution exposure (<2 µm) is performed, particularly with a high-resolution writing head that has a limited depth of field.

[0076] There figure 12 represents a first step in a third variant of the irradiation steps of figures 4 And 5 of the manufacturing process. The figure 12 Introduced as a third variant, this represents a special case of the second variant that can be advantageous. Indeed, the figure 12 represents the irradiation of the first part of the photosensitive resin 13 with initial optical parameters: a first focusing f1 and, a first wavelength λ1 and / or a first irradiation energy E1. This initial configuration allows a first dose of predetermined irradiation energy to be delivered to the first part of the photosensitive resin 13 located at the first depth P1. As an example, if the photosensitive resin 13 is SU-8 and has a thickness of 400 µm, we can consider that the first depth P1 is 300 µm, the first wavelength λ1 is 365 nm and / or the first irradiation energy E1 is 235 mJ / cm².

[0077] There figure 13 represents a second step of the third variant of the irradiation steps of figures 4 And 5 of the manufacturing process. Specifically, the figure 13 represents the irradiation of the second part of the photosensitive resin 13 with second optical parameters: a second focusing f2, and a second wavelength λ2, and / or a second irradiation energy E2. This second configuration allows a second predetermined dose of irradiation energy to be delivered to the second part of the photosensitive resin 13 located at the second depth P2. In the example given above, in which the photosensitive resin 13 has a thickness of 400 µm, we can consider that the second depth P2 is 100 µm, the second wavelength λ2 is chosen between 365 nm and 405 nm, typically 365 nm, 380 nm, 395 nm or 405 nm and / or the second irradiation energy E2 is 210 mJ / cm2.

[0078] In general, it is possible to plan to increase the irradiation energy by 10% at each increment in depth, in particular to compensate for losses due to absorption of the resin in the upper layers, and / or to take a longer wavelength at each increment in depth, to penetrate the upper layers more easily.

[0079] To that end, as shown by figures 12 And 13 The irradiation device 20 can be designed to adjust an exposure time, use, from among a plurality of irradiation sources 21, irradiation sources 21 having a specific wavelength, adjust an optical device 22 to filter (with high-pass or low-pass filters) a portion of the emitted irradiation, adjust the position of a focal plane, adjust a diaphragm opening... Consequently, between the first configuration of the figure 10 ou 12 and the second configuration of the figure 11 Or 13The irradiation of the resin is not maximal at the same depth, which ensures cross-linking of the resin 13 which will offer, after the development of the figure 6 , sides perfectly oriented vertically, or with controlled orientation or angling effects. Industrial application

[0080] A method for manufacturing a mold according to the present invention, and the manufacture of a watch part or a piece of jewelry, are capable of industrial application.

[0081] It will be understood that various modifications and / or improvements obvious to a person skilled in the art can be made to the different embodiments of the invention described in this description without departing from the scope of the invention.

[0082] In particular, it can be noted that between the first configuration of the figure 10 ou 12 and the second configuration of the figure 11 Or 13, irradiation may or may not be interrupted while the irradiation device 20 adjusts or modifies the irradiation parameters.

[0083] The fabrication of a single-level mold has been described, but this disclosure can easily be applied to a multi-level mold. Initial, intermediate, or final steps of curing, heating, plasma exposure, machining, grinding, deposition of conductive or bonding layers can also be included. The use of other photosensitive resins and other irradiation sources is also possible. In addition to the described steps, a physical mask can be used for other purposes or to irradiate the photosensitive resin.

Claims

1. A method for manufacturing a mold for electroplating or metal growth of a watch component (31, 32) or a piece of jewelry (31, 32), comprising the steps of: - obtaining at least one base substrate (11), - depositing at least one layer of photosensitive resin (13) onto said at least one base substrate (11), - irradiating at least a first portion of said at least one layer of photosensitive resin (13) - characterized: - in that the irradiation of said at least a first portion of said at least one layer of photosensitive resin (13) comprises a step of projecting onto said at least one layer of photosensitive resin (13) at least a first irradiation pattern (PM) corresponding to at least a first portion of a first piece of watchmaking or jewelry (31, 32), - and in that the irradiation of the first pattern (PM) of irradiation is free from masking.

2. A manufacturing method according to claim 1, comprising, after irradiating the first portion of said at least one layer of photosensitive resin (13), irradiating a second portion of said at least one layer of photosensitive resin (13) by projecting onto said at least one layer of photosensitive resin (13) a second irradiation pattern (DM) corresponding, for example, to a second portion of the first watch or jewelry piece (31, 32) or preferably to at least a second watch or jewelry piece (31, 32).

3. A manufacturing method according to claim 2, wherein the first portion of said at least one layer of photosensitive resin (13) and the second portion of said at least one layer of photosensitive resin (13) are distinct, for example separated by a predetermined distance or arranged on two different base substrates or arranged on two different layers of photosensitive resin (13).

4. A manufacturing method according to claim 3, comprising a step, preferably carried out between the irradiation of the first portion and the irradiation of the second portion, consisting of imposing a relative displacement between an irradiation source and said at least one base substrate (11) or said at least one photosensitive resin layer (13).

5. A manufacturing method according to claim 2, wherein the first portion of said at least one layer of photosensitive resin (13) and the second portion of said at least one layer of photosensitive resin (13) are adjacent or partially overlap.

6. Manufacturing method according to claim 5, wherein the projection of the second pattern (DM) of irradiation includes the irradiation of at least a part of said at least one layer of the photosensitive resin (13) already irradiated, and includes the irradiation of at least a part of said at least one layer of the photosensitive resin (13) not already irradiated.

7. A manufacturing method according to any one of claims 1 to 6, wherein: - the projection of the first irradiation pattern (PM) includes a step of structuring a source irradiation beam to obtain the first irradiation pattern (PM), and / or - the projection of the second irradiation pattern (DM) includes a step of structuring the source irradiation beam to obtain the second irradiation pattern (DM).

8. A manufacturing method according to any one of claims 2 to 7, wherein the projection of the first irradiation pattern (PM) and the projection of the second irradiation pattern (DM) are separated by a period of irradiation stoppage.

9. A manufacturing method according to any one of claims 2 to 8, wherein the projection of the first irradiation pattern (PM) and the projection of the second irradiation pattern (DM) are carried out in succession, preferably without a period of irradiation interruption.

10. A manufacturing method according to any one of claims 1 to 9, wherein the projection of the first irradiation pattern (PM) and / or the projection of the second irradiation pattern (DM) comprises the generation of a digital image to be projected.

11. A manufacturing method according to any one of claims 1 to 10, wherein the projection of the first irradiation pattern (PM) and / or the projection of the second irradiation pattern (DM) comprises the use of a light valve and / or a mirror and / or a light modulator and / or a liquid crystal display.

12. A manufacturing method according to any one of claims 1 to 11, wherein the projection of the first irradiation pattern (PM) and / or the projection of the second irradiation pattern (DM) comprises the simultaneous irradiation of a continuous surface greater than 0.0001 mm² 2 , preferably greater than 0.001mm 2 , preferably greater than 0.1 mm 2 , preferably greater than 0.3 mm 2 , preferably greater than 0.5 mm 2 , preferably greater than 0.7 mm 2 .

13. A manufacturing method according to any one of claims 2 to 12, wherein the projection of the first irradiation pattern (PM) and / or the projection of the second irradiation pattern (DM) comprises: - the delivery of a first dose of predetermined irradiation energy, for example to a first depth in the photosensitive resin (13), - an adjustment and / or a modification of an irradiation characteristic, for the delivery of a second dose of predetermined irradiation energy, for example to a second depth in the photosensitive resin (13), carried out after the delivery of the first dose of predetermined irradiation energy to the first depth in the photosensitive resin (13). 14.A manufacturing method according to any one of claims 1 to 13, wherein the projection of the first irradiation pattern (PM) and / or the projection of the second irradiation pattern (DM) comprises: - a first irradiation phase, - an adjustment and / or modification of an irradiation characteristic, such as an adjustment and / or modification of a focus of radiation emitted during irradiation, such as a modification of the relative position of a focal plane of the emitted radiation with respect to an external surface of the photosensitive resin (13), such as an adjustment and / or modification of a wavelength of radiation emitted during irradiation, such as an adjustment and / or modification of a resolution of radiation emitted during irradiation, such as an adjustment and / or modification of an irradiation power or irradiation energy - a second irradiation phase carried out with the adjusted or modified irradiation characteristic.

15. A manufacturing method according to any one of claims 1 to 14, comprising at least one step of texturing said at least one layer of photosensitive resin (13) to form at least one impression to form the timepiece (31, 32) or the jewelry piece (31, 32).

16. Method for manufacturing a watch part (31, 32) or a piece of jewelry (31, 32), comprising: - the manufacture of a mold (10) for electroplating or metal growth according to any one of claims 1 to 15, - at least one electroplating or metal growth step in the mold (10) to form the watch part (31, 32) or the piece of jewelry (31, 32).

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