Method for manufacturing exterior part

Abstract

To provide a method for manufacturing an exterior part.SOLUTION: A method comprises the steps of: manufacturing a substrate 11 including a cavity 110; manufacturing, by molding, a decorative element 12 made of a transparent polymer material having a reflective particle filler, the decorative element is formed so as to have at least one decorative head 120 connected to an anchoring foot 121; and fastening the decorative element in the cavity so that the anchoring foot cooperates with the cavity in a form-fitting manner.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to the decoration of watches, jewelry or fashion items, and more particularly to the manufacture of exterior components including one or more decorative elements simulating precious stones.

[0002] In this document, the term "precious stone" is used without distinction between precious and semi-precious stones.

[0003] This method can be advantageously applied to any exterior component in the fields of watchmaking, jewelry, or fashion items such as leather goods, glasses, writing instruments or portable electronic devices.

Background Art

[0004] To give high added value to an object, one or more precious stones are often set and decorated on a pedestal. This significantly increases the perceived value of the object.

[0005] For both economic and ecological reasons, precious stones can be synthetically manufactured in the laboratory. In particular, manufacturing precious stones in the laboratory is less energy-intensive than extracting natural precious stones by mining, so the price of synthetic stones is between 30% and 40% lower than that of equivalent natural stones.

[0006] A further advantage of synthetically manufactured stones is that they have the same visual appearance as natural mined stones because their atomic structure is the same as that of natural mined stones.

[0007] To further reduce the manufacturing cost of this type of decoration, decorative elements simulating the appearance of precious stones using polymer materials have been developed. However, although the manufacture of these decorative elements requires only a fraction of the energy required to manufacture synthetically made stones, their appearance is not suitable as a substitute for these stones.

[0008] Accordingly, there is a need for a decorative element that maintains the luster or sparkle characteristic of precious stones and, thus, gives the decorated article an appealing multitude of attractive appearances similar to those described above, while being manufactured at low cost and with low energy consumption. SUMMARY OF THE INVENTION

[0009] To this end, the present invention relates to a method for manufacturing an exterior component, the method comprising: · manufacturing a substrate including a cavity; · manufacturing a decorative element made from a transparent polymeric material having reflective particle fillers by molding, the decorative element being formed to have at least one decorative head connected to an anchor leg; · fastening the decorative element in the cavity such that the anchor leg cooperates with the cavity by shape fitting.

[0010] In certain implementations, the present invention may further include one or more of the following features. These features should be considered either alone or in any technically possible combination.

[0011] In certain embodiments, the decorative element is manufactured by injection molding and the anchor leg is formed by an injection sprue.

[0012] In certain implementations, in the step of manufacturing the decorative element, the decorative element is manufactured such that the anchor leg forms a support structure connecting a plurality of decorative heads together.

[0013] In certain implementations, an opaque layer is deposited on the anchor leg by physical vapor deposition, by spray or selective dip coating, or by injection molding during the manufacturing process of the decorative element.

[0014] In certain implementations, in the step of manufacturing the decorative element, the decorative element is manufactured to include a decorative head connected to a unique anchor leg of the decorative element.

[0015] In a specific implementation example, in the step of fastening the decorative element, the anchor leg is joined to a portion of the cavity having a complementary shape.

[0016] In a specific implementation example, in the step of fastening the decorative element, the anchor leg extends beyond the substrate by an end portion, and the end portion is deformed after being heated under heat, that is, softened to such an extent as to be sufficiently deformed, so as to bring about a permanent joint between the decorative element and the substrate.

[0017] In a specific implementation example, in the step of manufacturing the decorative element, the polymeric material is a thermoplastic selected from polycarbonate, polyamide or poly(methyl methacrylate).

[0018] In a specific implementation example, in the step of manufacturing the decorative element, the polymeric material is selected to have a light transmittance of more than 80%, or more than 90%, or more than 95%.

[0019] In a specific implementation example, in the step of manufacturing the decorative element, the reflective particles consist of flakes of metallic material and / or nacre, or consist of glass particles having a reflective coating.

[0020] In a specific implementation example, in the step of manufacturing the decorative element, the mass ratio of the reflective particle filler is less than 1%.

[0021] In a specific implementation example, in the step of manufacturing the decorative element, a thin reflective layer is deposited on at least one surface of the decorative element intended to face the cavity of the substrate.

[0022] In a specific implementation example, in the step of manufacturing the substrate, the reflective layer is deposited in the cavity.

[0023] In a specific implementation example, the thin reflective layer is deposited by physical vapor deposition and is made of SiO2 or TiO2.

[0024] In a particular implementation example, when the decorative element is being formed, the walls of the mold that are intended to form the decorative head have a mirror-polished surface finish.

[0025] In a particular implementation example, the method includes the step of polishing the decorative head so that its surface has a mirror-polished surface finish.

[0026] In a particular implementation example, in the step of manufacturing the decorative element, a luminescent particle filler is incorporated into the polymer material at a rate of less than 1% by mass.

[0027] In a particular implementation example, in the step of manufacturing the decorative element, once the decorative element is obtained by molding, a thin layer of the luminescent material is deposited on the surface of the head that is intended to be placed facing the cavity in the substrate.

[0028] The present invention further relates to an exterior component manufactured by the above method.

Brief Description of the Drawings

[0029] Other features and advantages of the present invention will become apparent from the following detailed description, which is given by way of example with reference to the accompanying drawings and is in no way limiting.

[0030]

Figure 1

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Figure 10

[0031] Note that, for clarity, the figures are not necessarily drawn to scale. DETAILED DESCRIPTION OF THE INVENTION

[0032] The present invention relates to a method of manufacturing an exterior component 10 such as a watch dial, flange, faucet or bezel, the method comprising the steps of manufacturing a substrate 11 and a decorative element 12, and then fastening the decorative element 12 to the substrate 11 to form the exterior component 10. These steps are detailed below.

[0033] During implementation of the method according to the invention, the substrate 11 is manufactured to include a cavity 110 intended to receive the decorative element 12. The substrate 11 may be made from any suitable material, such as a metal, ceramic or polymer material. It should be noted that, although the substrate 11 may have a plurality of cavities 110, for clarity, the text and drawings describe it as having a single cavity 110.

[0034] In particular, the cavity 110 may have a constant cross-section as shown in FIG. 3, or may have a proximal portion 11 opening onto an outer surface 112 of the substrate 11 that is intended to be visible to the user and that is extended by a distal portion 113 with a reduced cross-section as shown in FIGS. 6 to 10.

[0035] The cavity 110 may be a blind cavity or a through cavity. In particular, in FIGS. 3, 6 and 7, the cavity 110 is shown to be a blind cavity, and in FIGS. 8 to 10, the cavity 110 is shown to be a through cavity that opens to the inner surface 114 of the substrate 11 on the side opposite to the outer surface 112 through its distal portion 113.

[0036] The decorative element 12 is manufactured by integral molding, as schematically shown in FIGS. 1 and 5, particularly regardless of the time sequence with respect to the step of manufacturing the substrate 11. It is made of a thermoplastic selected from transparent polymer materials such as polycarbonate, polyamide, or poly(methyl methacrylate).

[0037] The decorative element 12 is preferably intended to have reflective particle fillers. These reflective particles increase the refractive index of the decorative element 12 and its reflectivity, helping to make its appearance closer to that of a precious stone. The reflective particles consist of a metal material and / or flakes of nacre, and their mass ratio is typically less than 1%. Furthermore, the polymer material is selected to have a light transmittance of 80%, or 90%, or even more than 95% so that the visual appearance of the decorative element 12 tends to be as similar as possible to that of a gemstone.

[0038] The decorative element 12 is formed to have at least one decorative head 120 connected to an anchor leg 121, as shown in the figures. Preferably, the decorative element 12 is manufactured by injection molding, and the anchor leg 121 is formed by all or part of the injection sprue, as shown in FIGS. 1 and 5. The anchor leg 121 is therefore cylindrical, and its cross-section may be circular, elliptical, polygonal, etc.

[0039] In the first exemplary embodiment shown in FIGS. 1 to 3, the decorative element 12 is manufactured such that the anchor legs 121 form a support structure that connects a plurality of decorative heads 120 together. As can be seen particularly in FIG. 2, the anchor legs 121 may in this case have an annular shape, and the decorative heads 120 are evenly distributed around the legs about the axis of rotation.

[0040] In this exemplary embodiment, the method may include depositing an opaque layer on the anchor legs 121 so as to visually separate the decorative heads that are transparent. Preferably, the opaque layer is configured to have the same visual appearance as the outer surface 112.

[0041] This opaque layer may be deposited on the anchor legs by vacuum thin-film deposition, by spraying or selective dip coating, or may be deposited by injection molding during the step of manufacturing the decorative element 12. Specifically, as shown in FIG. 4, the opaque layer can be bi-injection molded together with the decorative heads 120 and the anchor legs 121. The opaque layer may be made of the same polymer material, but has, for example, an opaque filler of a given color.

[0042] In the second exemplary embodiment shown in FIGS. 5 to 10, the decorative element 12 is manufactured to include a single decorative head 120 connected to a unique anchor leg 121.

[0043] Preferably, in the step of manufacturing the decorative element 12, a thin reflective layer is deposited on at least one surface of the decorative element 12 that is intended to face the cavity 110 of the substrate 11. Alternatively, in the step of manufacturing the substrate 11, the reflective layer is deposited in the cavity 110. The thin reflective layer may be deposited, for example, by vacuum evaporation, and is made of, for example, SiO2 or TiO2.

[0044] Advantageously, the walls of the mold intended to form the decorative head 120 have a mirror-polished surface finish, and the surfaces of the decorative head 120 also have a mirror-polished surface finish. Alternatively, the method may include the step of polishing the decorative head 120 so that its surfaces have a mirror-polished surface finish. This feature improves the transparency of the decorative head 120.

[0045] Another feature of the present invention that enables enhancing the attractiveness of the visual appearance of the decorative element 12 consists of incorporating a luminescent particle filler in a proportion of less than 1% by mass into the polymer material during the step of manufacturing the decorative element 12. Alternatively or additionally, a thin layer of luminescent material may be deposited on the surface of the head intended to face the cavity 110 of the substrate 11.

[0046] Once the substrate 11 and the decorative element 12 are manufactured, the decorative element 12 is fastened to the cavity 110 of the substrate 11. Specifically, during this step, the anchor legs 121 cooperate with a part of the cavity 110 having a complementary shape.

[0047] More specifically, during the fastening step, the anchor legs 121 are engaged with the cavity 110 until the decorative element 12 comes to rest, for example, by its decorative head 120. The decorative element 12 can be fastened to the cavity 110 by joining the legs inside the cavity 110, for example, when the cavity is blind, as shown in FIG. 7.

[0048] Alternatively, when the cavity 110 is a through-cavity, as shown in FIG. 9, the anchor leg 121 can extend such that the end 122 extends beyond the substrate 11. This end 122 is deformed under heat (i.e., after the material has been heated and softened) to produce a radially extending lip of material that forms an axial stop, as shown in FIG. 10, for example, by crushing. This axial stop holds the decorative element 12 in place within the cavity 110. Needless to say, when the end 122 of the decorative element 12 is deformed, the end 122 is subjected to a force that resists the force required to crush the material of the end 122.

[0049] In general, it should be noted that the implementation examples and embodiments considered above are described as non-limiting examples, and thus other alternative examples are possible.

[0050] For example, in the drawings, the decorative head 120 is shown as having facets, a table, a crown, and a pavilion, similar to a cut gemstone, but these may have different appearances.

Claims

1. A method for manufacturing an exterior part (10), comprising the steps of: - manufacturing a substrate (11) containing a cavity (110); - manufacturing by moulding a decorative element (12) made of a transparent polymer material with a reflective particle filler, said decorative element (12) being formed with at least one decorative head (120) connected to an anchoring leg (121); - fastening said decorative element (12) in said cavity (110) such that said anchor legs (121) cooperate with said cavity with a form fit.

2. 2. The method according to claim 1, wherein the decorative element (12) is manufactured by injection molding and the anchoring legs (121) are formed by an injection sprue.

3. 2. The method according to claim 1, wherein in the step of manufacturing the decorative element (12), the decorative element is manufactured such that the anchor legs (121) form a support structure connecting a number of decorative heads (120) together.

4. 4. The method according to claim 3, wherein an opaque layer is deposited on the anchoring legs (121) by vacuum thin film deposition during a step of manufacturing the decorative element (12), by spraying or selective dip coating, or by injection molding.

5. 2. The method according to claim 1, wherein in the step of manufacturing the decorative element (12), the decorative element (12) is manufactured to include a decorative head (120) connected to a unique anchoring leg (121).

6. 6. The method according to claim 5, wherein in the step of fastening the decorative element (12), the anchor legs (121) are joined to a portion of the cavity (110) having a complementary shape.

7. 6. The method according to claim 5, wherein in the step of fastening the decorative element (12), the anchor legs (121) extend with ends (122) beyond the substrate (11), and the ends (122) are deformed under heat to provide a permanent bond between the decorative element (12) and the substrate (11).

8. 2. The method according to claim 1, wherein in the step of manufacturing the decorative element (12), the polymeric material is a thermoplastic selected from polycarbonate, polyamide or poly(methyl methacrylate).

9. 2. The method according to claim 1, wherein in the step of manufacturing the decorative element (12), the polymer material is selected to have a light transmittance of more than 80%.

10. 2. The method according to claim 1, wherein in the step of manufacturing the decorative element (12), the reflective particles consist of flakes of metallic material and / or mother of pearl.

11. 2. The method according to claim 1, wherein in the step of manufacturing the decorative element (12), the mass proportion of the reflective particle filler is less than 1%.

12. 2. The method according to claim 1, wherein in the step of manufacturing the decorative element (12), a thin reflective layer is deposited on at least one face of the decorative element (12) intended to be placed facing the cavity (110) of the substrate (11).

13. The method of claim 1 , wherein in the step of manufacturing the substrate (11) a reflective layer is deposited in the cavity (110).

14. 13. The method of claim 12, wherein the thin reflective layer is deposited by vacuum evaporation and is made of SiO2 or TiO2.

15. 2. The method according to claim 1, wherein the walls of the mold intended to form the decorative head (120) when the decorative element (12) is molded have a mirror-polished surface finish.

16. The method of claim 1 including polishing the decorative head (120) such that a face thereof has a mirror polished surface finish.

17. 2. The method according to claim 1, wherein in the step of manufacturing the decorative element (12), glittering particle fillers are incorporated into the polymer material in a proportion of less than 1% by weight.

18. 2. The method according to claim 1, wherein in the step of manufacturing the decorative element (12), once the decorative element (12) is obtained by molding, a thin layer of photoluminescent material is deposited on the face of the head intended to be placed facing the cavity (110) of the substrate (11).

19. An exterior part (10) manufactured using the method according to the claims.

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