CH719279A2 - Method of manufacturing a dial. - Google Patents

Abstract

The invention relates to a method for manufacturing a dial (4) of a watch comprising at least one pattern on a visible face of the dial (4), said method comprising a step of designing a support plate (3) comprising the dial (4) and a step of producing at least one pattern on a visible face of said dial during which step is carried out an arrangement of this support plate (3) in a mold formed by the reversible assembly of a first and a second part (8a, 8b), said arranging step comprising a sub-step of forming at least one cavity (7) in this mold by the association of the first part (8a) comprising at least one imprint (5) with the visible face of the dial (4), and a construction of a draft of each pattern on the visible face of the dial (4) said step comprising a sub-step of overmolding by injection of injectable material into the cavity (7) by means of a through opening (18a) formed in the said dial (4) provided with an inlet orifice of the said cavity (7), the production step providing for a finalization of the pattern comprising a sub-step of applying a coating to all or part of said overmolded blank on the dial (4) after performing one of the following sub-steps of this finalization step: - step of disassembling the first part (8a) from the second part (8b) of the mould, or • a sub-step of removing said mold from the support plate (3) comprising the dial (4) provided with at least a draft of a pattern overmolded on its face.

Description

Technical field of the invention

The invention relates to a method and a system for manufacturing a dial of a watch provided with at least one pattern included on a surface of this dial intended to be arranged facing a glass / crystal of the watch.

The invention also relates to the dial comprising this pattern.

The invention also relates to the watch comprising such a dial.

Technology background

[0004] The methods for manufacturing dials generally include operations for machining a visible surface of this dial before making the appliques. Such appliques are often made from transfer operations, even screen printing or stamping of the lower surface of the dial. Stamping/machining operations of a metal plate then gluing on the visible surface of this dial can also be implemented to produce such appliques.

[0005] However, the solutions proposed by these processes remain unsatisfactory with regard to the requirement criteria for the manufacture of dials that are in particular. the aesthetic appearance, the absence of defects or scratches likely to result from machining operations and the robustness.

[0006] In this context, it is understood that there is therefore a need to develop alternative solutions that do not have the disadvantages mentioned above.

Summary of the invention

The object of the present invention is to overcome all or part of the aforementioned drawbacks by proposing a method and a system for manufacturing a watch dial that is of high quality with great versatility and durable over time.

[0008] To this end, the invention relates to a method of manufacturing a dial of a watch comprising at least one pattern on a visible face of the dial, said method comprising a step of designing a support plate comprising the dial and a step of producing at least one pattern on a visible face of said dial during which step is carried out: - an arrangement of this support plate in a mold formed by the reversible assembly of a first and a second part, said arrangement step comprising a sub-step of forming at least one cavity in this mold by associating the first part comprising at least one imprint with the visible face of the dial; – a construction of a draft of each pattern on the visible face of the dial, said step comprising a sub-step of overmolding by injection of material that can be injected into the cavity via a through opening made in said dial provided with a inlet to said cavity; – a finalization of the outline of the pattern comprising a sub-step of applying a coating to all or part of said overmolded outline on the dial after carrying out one of the following sub-steps of this finalization step: • a sub-step of disassembling the first part from the second part of the mould, or • a sub-step of removing said mold from the support plate comprising the dial provided with at least one outline of a pattern overmolded on its face .

[0009] In other embodiments: - the design step comprises a sub-step of making several through holes in the thickness of the body of a support plate blank, said holes delimiting in such a blank plate the edge of a dial blank; – the design step includes a sub-step of creating at least one through opening and at least one blind opening in the thickness of the dial blank; – the design step includes a sub-step of applying at least one coating to an upper face of this dial blank; – said arrangement step comprises a sub-step of reversible assembly of the second part with the support plate comprising the dial, said sub-step comprising a phase for connecting one end of an injection circuit provided in this second part with the inlet of the through opening of the dial; - Said sub-step of removal comprises a phase of rupture of an injection point linking said dial to the second part; – the overmolding sub-step comprises a phase of regulating the temperature of said mold in particular during a period extending before the start of the phase of injection of injectable material into the cavity until the end of this phase injection of material or even after this end of this injection phase, - the overmolding sub-step comprises a phase of placing said cavity under vacuum before the phase of injecting the injectable material into this cavity; – the application sub-step comprises a phase of depositing a decorative and/or functional material on a visible external face of the outline of the pattern overmolded on the dial; – the method comprises a step of producing at least one imprint in the first part from at least one original part relating to said at least one pattern to be manufactured.

[0010] The invention also relates to a system for manufacturing a dial of a watch comprising at least one pattern on a visible face of the dial implementing this method, the system comprising: - a device for designing a plate of support including the dial; – a mold formed by the reversible assembly of a first part and a second part configured to receive a support plate for the dial, the mold comprising at least one cavity formed by the association of the first part comprising at least one imprint with the visible face of the dial, each cavity participating in the production of an outline of the pattern from overmolding by injection of material which can be injected onto said visible face, and – a device for applying a coating to said outline overmoulded on the visible face of the dial participating in the finalization of this outline of the pattern.

The invention also relates to a dial for a watch comprising at least one pattern capable of being produced on its visible face using this process.

The invention also relates to a watch comprising such a dial.

Brief description of figures

The aims, advantages and characteristics of the present invention will emerge more clearly from the detailed description which follows, made in conjunction with the appended figures listed below: - Figure 1 is a representation of a system for manufacturing a dial of a watch provided with at least one pattern, according to one embodiment of the invention; - Figure 2 is a flowchart relating to a method of manufacturing the dial provided with at least one pattern, according to the embodiment of the invention; - Figure 3 is a sectional view of part of a mold of the system, according to the embodiment of the invention; – Figure 4 is a representation of a support plate comprising the dial here the dial of the watch, in this figure can be seen a visible face of this dial which is provided with several outlines of patterns, such as appliques, overmolded on this face, according to the embodiment of the invention; – Figure 5 is a representation of the support plate comprising the dial here the dial of the watch in this figure can be seen a hidden face of this dial and which is connected to a core formed essentially by a second part of the mold not shown , according to the embodiment of the invention; - Figure 6 is a side view of the support plate comprising the dial and a sprue formed in the mold, according to the embodiment of the invention; - Figures 7 and 8 are sectional views of different variants of pattern blanks molded onto the dial, according to the embodiment of the invention, and - Figure 9 shows a watch comprising a dial provided with at least a pattern, according to one embodiment of the invention.

Detailed description of the invention

Figure 1 shows a schematic representation of a system 1 for producing at least one pattern 10 on a dial 4 of a watch 100. This pattern 10 shown in Figures 1, 3, 4 to 9, is produced on a visible face 21a, also called the upper face, of this dial 4, that is to say on a face 21a which can be seen by the wearer of the watch 100 when this dial 4 is mounted in this part 100. This face 21a of dial 4 is said to be "visible" in reference to the possibility it has of being able to be perceived when it is mounted in watch 100 and this, unlike the other face 21b of this dial 4 which is opposite to this visible face 21a for example when this element 4 is a dial.

[0015] Such a system 1 is capable of being implemented within an automatic assembly installation (or automatic assembly line) dedicated to the manufacture of all or part of a watch 100. In such a context, this system 1 participates in manufacturing and ensuring the distribution of trim elements 4 comprising at least one pattern 10 within this automatic assembly installation.

[0016] The watch 100 consists of trim elements 4 and watch components (not shown) which are assembled together. In this context, the covering elements 4 can be visible or observable elements of the watch 100 when the latter is in particular worn by the user also called the wearer. With regard to watchmaking components, they include, in a nonlimiting non-exhaustive manner, elements constituting the watchmaking movement, the seals and/or rings included in this watch 100. Under these conditions, it is therefore understood that each dial 4 forms part of the elements of the 100 watch that surround the watch movement and give the watch its external appearance, aesthetics and style. By way of example, this dial 4 can be, in a non-limiting and non-exhaustive manner, a dial, a flange, a bezel, etc.

Note that in the embodiment described and with reference to Figure 9, the dial 4 is here the dial of the watch 100 and the pattern 10 is an application of this dial.

As we mentioned above, this dial 4 also includes a so-called hidden face 21b, also called the lower face, which is a face opposite the visible face 21a (visible in Figures 4 to 8).

[0019] With reference to Figures 1 and 3, this system 1 comprises in a non-exhaustive and non-limiting manner: - a mold 2 formed by the reversible assembly of a first part 8a with a second part 8b capable of receiving a plate of support 3 comprising at least one dial 4. -a device 11 for injecting a material that can be injected into this mold 2; – a device 12 for applying a coating to a blank of the pattern 10 overmolded on the dial 4; – a device 13 for designing an original part also called “master” relating to the pattern 10 to be manufactured, notably implementing lithography techniques, in particular optical lithography by ultraviolet projection, optical lithography by DUV projection (acronym of “ Deep Ultra-Violet“), immersion lithography, double exposure lithography, extreme ultraviolet lithography and/or nanoimprint lithography; – a device 14 for producing said at least one pattern 10 from the original part, in particular implementing Ni shims or BMG replication techniques; - a vacuum device 15 of said mold 2 and/or a device 16 for regulating the temperature within this mold 2; - a device 17a for removing and arranging the support plate 3 of at least one dial 4 in the mold 2, and - a design device 17b of the support plate.

In this configuration, the design device 17b of the support plate comprises. - a module for producing several through holes in the thickness of the body of a support plate blank, said holes delimiting in such a plate blank the edge of a dial blank; – a module for creating at least one through opening 18a and at least one blind opening 18b in the thickness of the dial blank; – a module for applying at least one coating to an upper face of this dial blank.

[0021] In this device 17b, the application module is provided in particular with an ejection member for this decorative and/or functional material, and/or with a member for spraying such a material and/or with a member for spraying a film/film comprising such a material. It will be noted that this module is also suitable for carrying out this application by PVD or lacquering or zaponnage.

In system 1, this mold 2 comprises a housing formed by the assembly of the first part 8a with the second part 8b and in which is capable of being arranged the support plate 3 comprising the dial 4. It is understood that the plate 3 can comprise a single dial 4 or alternatively several covering elements 4.

In this mold 2, the second part 8b comprises a reception face configured to receive such a support plate 3. More specifically, the support plate 3 is mounted on the reception face of the second part 8b so as to that the hidden face 21b of the dial 4 is arranged facing or even in contact with all or part of this reception face. In this configuration, the visible face 21a of the dial 4 is for its part facing and in contact with an internal face of the first part 8a. In other words, the support plate 3, and therefore the dial 4, is arranged in the housing of this mold 2 by being sandwiched between the first and second parts 8a, 8b of this mold 2.

The inner face of this first part 8a of the mold 2 may comprise a single cavity 5 or several cavities 5 each relating to a pattern 10 to be overmolded on the visible face 21a of the dial 4. These cavities 5 each have a shape hollow defined in this flat inner face of the first part 8a.

[0025] The visible face 21a of dial 4 comprises a zone 6, also called overmolding zone 6, which is defined to form with said impression 5 a cavity 7 into which an injectable material is injected and this, so as to participate in the design of said blank 20 of pattern 10. This cavity 7 defines the final shape of said blank 20 and therefore of pattern 10 which are produced by the cooperation of indentation 5 and corresponding zone 6 of visible face 21a of dial 4. In this configuration, this zone 6 is therefore arranged opposite this said cavity 5 when the first part 8a and the dial 4 are assembled with each other. It will be noted that the mold 2 comprises as many cavities 7 as this first part 8a comprises cavities 5 and/or as the dial 4 comprises overmoulding zones 6.

In this context, when the system 1 is provided with the device 16 for regulating the temperature within said mold 2, the first part 8a can then comprise an injection circuit (not shown) defined in the body of this first part 8a which is essentially arranged below each cavity 5. Such a circuit is connected to the temperature regulating device 16 which is then capable of causing the circulation of a cooling fluid or a heating fluid in this circuit.

In the dial 4 included in the support plate 3, the visible face 21a and the hidden face 21b are preferably flat. These visible and hidden faces 21a, 21b are also called respectively the upper and lower faces of dial 4. In this mold 2, the visible face 21a of this dial 4 is able to be in contact with the internal face of the first part 8a when this first part 8a is assembled to the second part 8b. In this configuration, it is understood that the dial 4 is arranged in this mold 2 by being sandwiched between these first and second parts 8a, 8b.

[0028] Referring to Figure 3, this dial 4 also includes at least one through opening 18a, also called through channel or through hole, connecting the hidden face 21b of the dial 4 to the receiving face of the second part 8b, this through opening 18a comprising a first end, called the outlet orifice, opening into the cavity 7 of the mold 2 and a second end opening onto the hidden face 21b of the dial 4 called the inlet orifice. It is understood that the dial 4 comprises at least as many through openings 18a as the mold 2 comprises cavities 7.

It will be noted with reference to Figures 7 and 8 that when the dial 4 is a dial, this through-opening 18a comprising injectable material participates in forming a foot 23a, of the pattern 10. This foot 23a is configured in particular in its form to ensure anchoring of this pattern 10 in the body of the dial 4. Moreover, the zone 6 which is provided to form with the said indentation 5 the cavity 7, can comprise in addition to this through opening 18a, a blind opening 18b , also called a blind hole, comprising an inlet orifice defined in the visible face 21a of the dial 4. Such a blind opening 18b, comprising injectable material, helps to form another foot 23b of the pattern 10 which is also configured in particular in its shape to anchor this pattern 10 in the body of the dial 4.

In this context, the body of these through and blind openings 18a, 18b is formed of a set of axial transverse sections S1, S2, S3, S4 which are perpendicular to a longitudinal axis A, B of these openings 18a, 18b . In this configuration, the through opening 18a extends along the longitudinal axis A connecting the centers of the inlet and outlet orifices to each other. With regard to the blind opening 18b, it also extends along the longitudinal axis B connecting the centers of the inlet orifice of the injectable material and the bottom of this opening 18b between them. These longitudinal axes A, B are substantially parallel or strictly parallel to each other. In this configuration, it will be noted that: - the through opening 18a comprises at least one axial transverse section S1, S3 between the inlet orifice and the outlet orifice, the surface of which is strictly different or substantially different from a surface of an axial cross-section including the inlet port and a surface of an axial cross-section including the outlet port; – the through opening 18a comprises at least one axial cross section S1, S3 between the inlet orifice and the outlet orifice, the surface of which is strictly different or substantially different from a surface of an axial cross section comprising the inlet or a surface of an axial cross-section comprising the outlet; – the through opening 18a comprises at least one axial cross section S1, S3 between the inlet orifice and the outlet orifice, the surface of which is • strictly greater than or substantially greater than a surface of an axial cross section comprising the outlet orifice, and/or • strictly lower or substantially lower than a surface of an axial cross-section comprising the inlet orifice; – the blind opening 18b comprises at least one axial cross section S2, S4 between the inlet orifice and the bottom, the surface of which is strictly different or substantially different from a surface of an axial cross section comprising the inlet and a surface of axial cross-section including the bottom; – the blind opening 18b comprises at least one axial cross section S2, S4 between the inlet orifice and the bottom, the surface of which is strictly different or substantially different from a surface of an axial cross section comprising the inlet or surface of an axial cross-section including the bottom; – the blind opening 18b comprises at least one axial cross section S2, S4 between the inlet orifice and the bottom, the surface of which is: • strictly greater than or substantially greater than a surface of an axial cross section comprising the outlet orifice, and/or • strictly less than or substantially less than a surface of an axial cross-section comprising the inlet orifice.

In this context and by way of example, in Figure 7 the through opening 18a and the blind opening 18b may have an essentially frustoconical shape or a shape similar to that of a tube whose body comprises two parts having different cross-sections or even different diameters as shown in Figure 8.

As we have mentioned, the mold 2 comprises at least one cavity 7. This cavity 7 is formed by assembling the cavity 5 included in the internal face of the first part 8a with the corresponding zone 6 of the visible face 21a of the dial 4. The zone 6 comprises the through opening 18a provided in the dial 4 which opens via its outlet orifice into the cavity 7. This through opening 18a is connected/connected via its orifice input to the injection device 11 of injectable material, via the injection circuit 9 defined in the second part 8b of the mold 2. It will be noted that in this configuration, when the cavity 7 also comprises a blind opening 18b, the inlet orifice of this opening is then defined in the overmoulding zone 6 of the visible face 21a of the dial 4.

In this configuration, the portion of injectable material which is solidified in the inlet orifice of the through opening 18a forms an injection point 22 which is defined to be broken in particular when the dial 4 is separated with the second part 8b as described below. Indeed, this injection point 22 participates in maintaining the support plate 3, and therefore the dial 4, on the second part 8b by linking it to a sprue 19 formed in this mold 2. This injection point 22 is preferably located at the inlet of the through opening 18a. In other words, this injection point 22 is located at the end or at the level of the base of the foot 23a, formed in the through opening 18a, of this pattern 10.

It will be noted that this core 19 which is visible in FIG. 6, comprises a first part formed by the solidification of the injectable material in the through opening 18a and a second part formed by the solidification of the injectable material in the circuit injection 9 made in the second part 8b.

[0035] In addition, in this configuration, it is well understood that the imprint 5 forms the visible part of the pattern 10 such as an applique when the dial 4 is a dial, and the corresponding zone 6 of the dial 4 participates as to it to the formation of the connecting part of this applies with the dial from the feet 23a, 23b of this applies.

As we have already mentioned, in this mold 2, the second part 8b is provided to be assembled in a reversible manner with a mounting face of the support plate 3 and/or with the hidden face 21b of the dial 4. This second part 8b comprises said at least one injection circuit 9 of injectable material connected at a first end to the injection device 11 and at a second end to each through opening 18a of the dial 4 of the support plate 3. It will be noted that when the system 1 is provided with the vacuum device 15 of the said mold 2, a vacuum circuit can be defined in the body of the second part 8b which is connected at one end to a through opening 18a of the dial 4 thus at another end to this vacuum device 15, said device 15 thus being capable of causing an air vacuum in each cavity 7 of the mold 2. In this configuration, it is understood that one of the functions of the second part 8b is to ensure the delivery of the injectable material to the through opening 18a for injection of material and to participate, if necessary, in placing the cavity 7 of the mold 2 under vacuum.

In this system 1, the device 12 for applying a coating to a blank 20 of the pattern 10 overmolded on the dial 4 is capable of applying/depositing a coating comprising a decorative material of metallic type and/or a material functional on an outer surface 24 of the blank 20 of this pattern 10. Such a device 12 may comprise a printing module provided in particular with a member for ejecting this decorative and/or functional material, and/or with a member for spraying such a material and/or a member for spraying a film/film comprising such a material. It will be noted that the sputtering member can be a direct current cathode sputtering member or even a high-power pulsed magnetron sputtering member better known by the acronym HIPIMS for “High Power Impulse Magnetron Sputtering”. It will be noted that other techniques can be implemented such as those known as "hot transfer" of the coating on the blank 20.

In this system 1, the decorative material can be formed from an ink, or else from a metal or a metal alloy. This decorative material participates in modifying the aesthetic appearance of the pattern 10 by being applied to the blank 20 of this pattern 10. As regards the functional material, it aims to confer on the pattern 10 physical and/or chemical functional characteristics linked for example to: – electrical conductivity, semiconducting or insulating character; – semi-conductivity; – electroluminescence; – photoluminescence (for example a reaction to ultraviolet radiation); – phosphorescence; – „X-chromism“ (photochrome, electrochrome, thermochrome, ionochrome, mecanochrome...); – electroactivation; – magnetism; - etc.

In this system 1, the injectable material used is for example an organic and/or composite material, or a metallic or ceramic material or even a thermodeformable, thermosetting or thermoplastic material. By way of example, this material may include the following elements: – loaded plastic of the SLN type (phosphorescent) and colored and/or fluorescent pigments; – ceramic filled polymer with and without color pigment; – an additive making it possible to give a metallic/shiny appearance, such as aluminum powder, metallic powder; – additive making it possible to make the polymer conductive (for technical reasons or for chemical/galvanic or other post-treatment); – additive giving an aesthetic result copying a material (mother-of-pearl, stone, etc.); – additive giving special mechanical and/or tribological characteristics; – BMG better known by the acronym „Bulk Metallic Glass“; – stainless material; – sinterable metallic material; – ceramics; – silicon, and/or – combination of one or other of these elements together or several of these elements together.

In this configuration, it is understood that such a system 1 can make it possible to manufacture several overmolded patterns 10 simultaneously on the visible face 21a of the dial 4. To do this, the first part 8a then comprises several cavities 5 and is able to participate with dial 4 in particular in obtaining a series of patterns 10 overmolded on the visible face 21a of this dial 4. Alternatively, it is clearly understood that the first part 8a can comprise a single imprint 5 relating to an outline of the pattern 10 overmoulded on the visible face 21a of the dial 4.

[0041] Referring to Figure 2, this system 1 implements a method for producing said at least one pattern 10 on the visible face 21a, of the dial 4 of the watch 100.

Such a method also includes a step 25 of designing the support plate 3 comprising the dial. Said step 25 comprising a substep 26a of producing several through holes in the thickness of the body of a support plate blank, said holes delimiting in such a plate blank the edge of a dial blank. In this configuration, the dial blank is retained to the rest of the body of the blank plate by parts of this plate each comprised between two holes.

This step 25 then comprises a sub-step 26b of creating at least one through opening 18a and at least one blind opening 18b in the thickness of the dial blank. As we have already mentioned, such an opening 18a is provided to then connect the hidden face 21b of the dial 4 to the receiving face of the second part 8b of the mould.

This step 25 then comprises a sub-step 27 of applying at least one coating to an upper face of this dial blank. It will be noted that this upper face corresponds to the visible face of the dial obtained in the support plate at the end of this design step 25. During this sub-step 27, several layers can be applied to this visible face.

For example, this sub-step 27 may include a phase 28 of deposition of at least one decorative layer in a translucent or transparent or even colored material. This so-called at least one layer of decoration can also include a functional material aimed at giving the dial ultimately and in particular on its visible face physical and/or chemical functional characteristics linked for example to: – electrical conductivity, semi-conductor character or insulator – semi-conductivity; – electroluminescence; – photoluminescence (for example a reaction to ultraviolet radiation); – phosphorescence; – „X-chromism“ (photochrome, electrochrome, thermochrome, ionochrome, mecanochrome...); – electroactivation; – magnetism; - etc.

[0046] In addition, this said at least one layer may comprise an acrylic or epoxy varnish and/or a material resistant to oxidation when the dial blank is made of metallic material.

As we have seen, such a design step 25 thus makes it possible to obtain the support plate comprising the dial and this, from a blank plate made of metallic material, metallic alloy and/or polymer, in which the blank plate was made the dial blank. This support plate is then used in the context of producing at least one pattern which may be two-dimensional or three-dimensional, on the visible face of dial 4.

More specifically, the method subsequently comprises a step 29 of producing at least one pattern on a visible face of dial 4 of the watch. This step 29 comprises a step 30 of producing at least one imprint 5 in the first part 8a from "at least one original part relating to said at least one pattern 10 to be manufactured. It is understood that this step 30 is capable of to participate in the production of as many indentations 5 as there are patterns 10 to be produced and this, so that such indentations 5 are overmolded on the same dial 4. This step 30 provides for the production of an imprint 5 from an original part, otherwise called a "master". This original part has a shape similar to that of the pattern 10 to be produced. It will be noted that the implementation of this step 30 may require as many original parts as there are 5 prints to be made.

In this context, the development step 30 includes a sub-step 31 of designing said original part implemented using a lithography technique. This lithography technique is chosen from the following techniques known to the state of the art and which are not described in more detail here: optical lithography by ultraviolet projection, optical lithography by DUV projection, immersion lithography, double exposure lithography, lithography extreme ultraviolet, nanoimprint lithography.

This development step 30 then includes a sub-step 32 of replication of the original part aimed at producing the trim elements 5 by reproducing a negative form of the original part. This sub-step 32 provides in particular for the implementation of replication techniques of the Ni shims or BMG (acronym “Bulk Metallic Glass”) type known from the state of the art and which are not described in more detail here.

Subsequently, the method includes a step 33 of arrangement in the mold 2 of the support plate 3 comprising the dial 4 said mold 2 being formed by the reversible assembly of the first and second parts 8a, 8b. During this step 33, the support plate 3 is positioned in the housing defined by the reversible assembly of these first and second parts 8a, 8b. Such an arrangement step 33 comprises a sub-step 34 of reversible assembly of the second part 8b with the support plate 3 comprising this dial 4. This sub-step 34 comprises a phase of connection 35 of one end of the circuit injection 9 made in this second part 8b with the inlet orifice of the through opening 18a of the dial 4. Such a sub-step 34 contributes to achieving an optimal connection between the end of the injection circuit 9 made in this second part 8b with the through opening 18a defined in the dial 4 and in particular with the inlet orifice of this opening 18a. It is understood that this circuit 9 comprises as many ends as the dial 4 comprises inlet orifices of through openings 18a. It will be noted that the inlet orifice is included in the hidden face 21b of the dial 4. Such an arrangement step 33 also comprises a sub-step 36 of forming at least one cavity 7 in this mold 2 by the association of the first part 8a comprising at least one imprint 5 with the visible face 21a of the dial 4. It will be noted that each cavity 7 is defined for the elaboration/formation of the blank 20 of the pattern 10. In other words, this cavity 7 of the mold 2, being formed by the association of at least one cavity 5 of the first part 8a of the mold 2 with the visible face 21a of the covering element of this mold 2, defines a space corresponding to the volume and the shape of the outline 20 of the pattern 10 which is produced here.

The method then comprises a construction step 37 of said at least one blank 20 relating to the pattern 10 on the visible face 21a of the dial 4. This step 37 comprises a sub-step of overmolding 38 by injection of injectable material into the cavity 7 through a through opening 18a formed in the said dial 4 provided with an inlet orifice of the said cavity 7. This sub-step 38 aims to produce an overmolding of the blank 20 of the pattern 10 on the zone 6 corresponding to the visible face 21a of the dial 4. Such a sub-step 38 comprises an injection phase 39 in this cavity 7 of the injectable material from the injection device 11 of this material. In this context, the injectable material coming from the injection device 11 is introduced into the cavity 7 by traversing the injection circuit 9 of injectable material defined in the second part 8b and the through opening 18a included in the dial 4 connecting this injection circuit 9 to said cavity 7. Thus, the injectable material then occupies the entire volume defined in the cavity 7 by overmolding the corresponding zone 6 of the visible face 21a of the dial 4 arranged opposite the imprint 5 and this, with a view to forming this outline 20 of the pattern 10.

Such a molding sub-step 38 may comprise the following phases: - a vacuum phase 40 of said cavity 7 before carrying out the phase of injection 39 of the injectable material into this cavity 7, and/ or - a regulation phase 41 of the temperature of the cavity 7 in particular during a period extending before the start of the injection phase 39 of injectable material into the cavity 7 until the end of this injection phase 39 of material even after this end of this infection phase 39.

Such phases of vacuum 40 and temperature regulation 41 aim to ensure structural homogeneity of the blank 20 of the pattern 10 during its overmolding on the dial 4 in order to eliminate the presence of any defect likely to be present on the visible external face of this blank 20. Such a defect may for example reside in the presence of a weld line on the visible external face of the blank 20, formed following the junction of two fluxes of flow of injectable material into cavity 7. Such a weld line is often present on blanks 20 of patterns 10 relating to appliques in the shape of a number 6, 8 or even 0.

During the implementation of the vacuum phase 40, the fluid present in the cavity 7, for example a gas such as air, is then evacuated from the cavity 7 before the injection phase 39 is carried out. .

During the realization of the regulation phase 41 of the temperature of the cavity 7, the temperature in the cavity 7 is then brought to a temperature which is higher or substantially higher than the temperature of the injectable material coming from the device. injection 11 of this material and this, before the realization of the injection phase 39. Thereafter, once the phase of injection 39 of the injectable material carried out that is to say completed, the cavity 7, is immediately cooled.

The method then comprises a step 42 of finalizing said at least one outline of the pattern 10. This step 42 comprises a sub-step of applying 43 a coating on all or part of said outline 20 of this pattern. 10 overmolded on the dial 4. Such an application sub-step 43 is implemented after the performance of one of the following sub-steps of this finalization step 42: • a disassembly sub-step 44 of the first part 8a of the second part 8b of the mold 2, or • a sub-step 45 of removing said mold 2 from the support plate 3 comprising the dial 4 provided with said at least one blank 20 of the pattern 10 overmoulded on the visible face of this dial 4.

Indeed, following one or the other of these two sub-steps 44, 45, the application sub-step 43 comprises a phase of depositing 46 decorative and/or functional material on the visible external face of each blank 20 of the pattern 10 overmoulded on this dial 4. By way of example, this deposition phase 46 may provide for the application on this external face of the blank 20 of a decorative material comprising a composition metallic. Such a deposition phase 46 can then be carried out according to a technology implementing cathode sputtering by direct current or even high-power pulsed magnetron sputtering better known by the acronym HIPIMS for “High Power Impulse Magnetron Sputtering”.

It will be noted that when application sub-step 43 is carried out following the disassembly sub-step 44 of the first part 8a from the second part 8b of the mold 2, the deposition phase 46 is carried out with the support plate 3 which is still mounted/fixed on the second part 8b of the mold 2. Moreover, in this context, following this deposition phase 46 the method provides for the implementation of the removal sub-step 45 of the support plate 3 of the mold 2.

[0060] In this method, the sub-step of removal 45 comprises a phase of rupture 47 of the injection point 22 linking the support plate 3 and/or the dial 4, comprising the blank 20 of the pattern 10 or the pattern 10, to the second piece 8b. This phase 47 comprises a sub-phase 48 of application of a force on the support plate 3 comprising this dial 4 aimed at causing a displacement in rotation or in translation of this plate relative to the second part 8b and thus causing the rupture of the injection point 22. It will be noted that once the injection point 22 is broken, the base of the foot of the pattern 10 formed in the through opening 18a is substantially flush with the hidden face 21b of the dial 4 or strictly flush with this hidden face 21b.

[0061] Once the support plate 3 has been extracted from this second part 8b, the dial 4 is then separated from the support plate 3 in order to be mounted in a watch or to be in turn finalized by the application of a coating layer on its remaining visible face 21a, that is to say on the portion of this face 21a which is not obscured by the pattern or patterns 10.

[0062] It will also be noted as we mentioned previously that each dial 4 can comprise several patterns 10 and under these conditions as many injection points 22 as there are patterns 10.

Thus the invention participates in particular in the production of at least one pattern 10 on the visible face 21a of trim elements 4 of timepieces.

Claims (13)

1. Method for manufacturing a dial (4) of a watch (100) comprising at least one pattern (10) on a visible face (21a) of the dial (4), said method comprising a design step (25) a support plate (3) comprising the dial (4) and a step (29) of producing at least one pattern on a visible face of said dial during which step (29) is carried out: – an arrangement (33) of this support plate (3) in a mold (2) formed by the reversible assembly of a first and a second part (8a, 8b), said arrangement step (33) comprising a sub-step of forming (36) at least one cavity (7) in this mold (2) by associating the first part (8a) comprising at least one imprint (5) with the visible face (21a ) of the dial (4); – a construction (37) of a blank (20) of each pattern (10) on the visible face (21a) of the dial (4), said step (37) comprising a sub-step of overmolding (38) by injection of material injectable into the cavity (7) via a through opening (18a) provided in the said dial (4) provided with an inlet orifice of the said cavity (7); – a finalization (42) of the blank (20) of the pattern (10) comprising a sub-step of applying (43) a coating on all or part of said blank (20) overmolded on the dial (4) after the completion of one of the following sub-steps of this finalization step (42): • a disassembly sub-step (44) of the first part (8a) of the second part (8b) of the mold (2), or • a sub-step of removing (45) said mold (2) from the support plate (3) comprising the dial (4) provided with at least one blank (20) of a pattern (10) overmolded on its face . 2. Method according to the preceding claim, characterized in that the design step (25) comprises a sub-step of producing (26a) several through holes in the thickness of the body of a support plate blank, said holes delimiting in such a plate blank the edge of a dial blank. 3. Method according to the preceding claim, characterized in that the design step (25) comprises a sub-step of creating (26b) at least one through opening (18a) and at least one blind opening (18b ) in the thickness of the dial blank. 4. Method according to any one of claims 2 and 3, characterized in that the design step (25) comprises a sub-step of applying (27) at least one coating on an upper face of this blank of dial 5. Method according to any one of the preceding claims, characterized in that said arrangement step (33) comprises a sub-step of reversible assembly (34) of the second part (8b) with the support plate (3 ) comprising the dial (4) said sub-step (34) comprising a connection phase (35) of one end of an injection circuit (9) arranged in this second part (8b) with the inlet orifice of the through opening (18) of the dial (4). 6. Method according to any one of the preceding claims, characterized in that said withdrawal sub-step (45) comprises a breaking phase (47) of an injection point (22) linking said dial (4) to the second piece (8b). 7. Method according to any one of the preceding claims, characterized in that the molding sub-step (38) comprises a regulation phase (41) of the temperature of said mold (2) in particular during a period extending before the beginning of the phase of injection (39) of injectable material into the cavity (7) until the end of this injection phase (39) of material or even after this end of this injection phase (39). 8. Method according to any one of the preceding claims, characterized in that the overmolding sub-step (38) comprises a vacuum phase (40) of said cavity (7) before the injection phase (39) of the injectable material in this cavity (7). 9. Method according to any one of the preceding claims, characterized in that the application sub-step (43) comprises a phase of depositing (46) a decorative and/or functional material on a visible external face of the draft (20) of the pattern (10) molded onto the dial (4). 10. Method according to any one of the preceding claims, characterized in that it comprises a step of producing (30) at least one imprint (5) in the first part (8a) from at least one part original relating to said at least one pattern (10) to be manufactured. 11. System (1) for manufacturing a dial (4) of a watch (100) comprising at least one pattern on a visible face (21a) implementing the method according to any one of claims 1 to 10, the system (1) comprising: – a design device (17b) of a support plate (3) comprising the dial (4); – a mold (2) formed by the reversible assembly of a first part (8a) and a second part (8b) configured to receive a support plate (3) of the dial (4), the mold (2) comprising at least one cavity (7) formed by the association of the first part (8a) comprising at least one indentation (5) with the visible face (21a) of the dial (4), each cavity (7) participating in the production of a blank (20) of the pattern (10) from an overmolding by injection of injectable material on said visible face (21a), and – a device (12) for applying a coating to said blank (20) molded onto the visible face (21a) of the dial (4) participating in the finalization of this blank (20) of the pattern (10). 12. Dial for a watch comprising at least one pattern capable of being produced on its visible face (21a) using the method according to any one of claims 1 to 10. 13. Watch (100) comprising a dial (4) according to the preceding claim.