CH715999A2 - Piece of jewelry in composite elastomer material. - Google Patents

Abstract

The invention relates to a piece of jewelry made of elastomeric composite material. According to the invention, the elastomeric composite material comprises an elastomeric matrix in which is dispersed between 0.5% and 4% by mass of cellulosic fibers, between 0 and 2% by mass of an antibacterial additive, between 0 and 5% by mass thermally conductive fillers, between 0 and 1% by mass of anti-odor agents, and between 0 and 1% by mass of silica.

Description

Field of the invention

The present invention relates to the technical field of materials based on elastomers. More specifically, the invention relates to a piece of jewelry made from an elastomeric composite material for the, a method of manufacturing parts, as well as the parts obtained.

[0002] In the present invention, piece of jewelry designates any object of adornment, but also components used in watchmaking or in jewelry. More particularly, the invention relates to bracelets, such as watch bracelets.

Background of the invention

[0003] Many elastomeric materials exist on the market and are known for their use as a bracelet, for example for their quality of comfort, of flexible touch and their resistance.

[0004] Thus, it is known from document JP 2000204265 to produce a thermoplastic elastomer material having antibacterial properties and having good resistance to aging.

[0005] Also known from patent EP 2 468 127 is a piece of jewelry, at least partially made of a composite material comprising an elastomeric matrix in which are dispersed reinforcing fillers chosen from the group comprising microfibers, polytetrafluoroethylene nanoparticles, and mixtures thereof, said composite material being obtained from a composition comprising between 60% and 95% by weight of at least one elastomer, between 0% and 5% by weight of microfibers and between 0% and 40% by weight of polytetrafluoroethylene nanoparticles, relative to the total weight of the composition, at least one of said reinforcing fillers being present.

[0006] However, these elastomeric materials used for bracelets or watch components in contact with the skin do not make it possible to obtain good evacuation of perspiration, the antibacterial properties only making it possible to neutralize bad odors, and the fibers present in the material only mechanically reinforce the latter. In addition, the bracelets are often subjected to friction or abrasion which tends to remove a certain amount of the antibacterial agent and therefore to reduce the effectiveness of the latter.

Summary of the invention

The object of the invention is in particular to overcome the various drawbacks of these known techniques.

More specifically, an objective of the invention is to provide a piece of jewelry made of an elastomeric material intended to be in prolonged contact with the skin (direct or indirect), and to obtain an elastomer with properties making it possible to improve the evacuation of perspiration, while maintaining good colorability and good resistance to aging (UV, perspiration, aesthetics, tearing).

These objectives, as well as others which will emerge more clearly below, are achieved according to the invention using a piece of jewelry made of elastomeric composite material, said elastomeric composite material comprising an elastomeric matrix in which is dispersed between 0 and 4% by mass of cellulosic fibers, between 0 and 2% by mass of an antibacterial additive, between 0 and 5% by mass of thermally conductive fillers, between 0 and 1% by mass of anti-bacterial agents -odors, and between 0 and 1% by mass of silica.

According to other advantageous variants of the invention: <tb> <SEP> - The elastomeric matrix is a fluoroelastomer of the fluorocarbon rubber type; <tb> <SEP> - the elastomeric material comprises short cellulosic fibers and long cellulosic fibers, the length of the cellulosic fibers being between 0.5mm and 1.5mm; <tb> <SEP> - the composite material comprises between 1.5% and 3.5% by mass of microfibers, and preferably 2% by mass of short microfibers and 1.5% by mass of long microfibers relative to the total weight of the composition; <tb> <SEP> - the elastomeric material comprises at least between 0 and 30% by mass of a coloring additive; <tb> <SEP> - the elastomeric material comprises less between 0 and 1% by mass of anti-odor agents; <tb> <SEP> - the elastomeric material comprises at least one mold release agent; <tb> <SEP> - the elastomeric material comprises between 0 and 1% by weight of a brightening agent.

The invention also and in particular relates to any timepiece made of elastomeric material according to the invention.

The invention also relates to a method of manufacturing a piece of jewelry according to the invention, the manufacturing method comprises the following steps: <tb> <SEP> - produce a composition comprising at least one elastomer, between 0.5% and 4% by mass of cellulosic fibers, between 0 and 2% by mass of an antibacterial additive, between 0 and 5% by mass of fillers thermally conductive, between 0 and 1% by mass of anti-odor agents, and between 0 and 1% by mass of silica; <tb> <SEP> - performing a molding of the composition obtained in the previous step; <tb> <SEP> - carry out the finishing steps for the molded part obtained during the second step.

According to this process, the elastomeric matrix is a fluoroelastomer of fluorocarbon rubber type.

Other characteristics and advantages of the invention will emerge more clearly on reading the following description of a particular embodiment of the invention, given by way of simple illustrative and non-limiting example.

Detailed description of the preferred embodiments

The invention relates to a piece of jewelry made of elastomeric composite material, said elastomeric composite material comprising an elastomeric matrix in which is dispersed between 0 and 4% by weight of cellulosic fibers, between 0 and 2% by weight of a antibacterial additive, between 0 and 1% of thermally conductive fillers, between 0 and 1% of anti-odor agents, and between 0 and 1% of silica.

According to the invention, the elastomeric material chosen for the matrix is chosen from fluoroelastomers.

The term "fluoroelastomer" is used in the general sense regardless of the fluorine content and denotes both fluoroelastomers whose main chain is partially substituted, that is to say fluoroelastomers commonly called FKM, as well as fluoroelastomers whose main chain is entirely substituted, that is to say perfluoroelastomers commonly called FFKM.

Preferably, the elastomer is a fluoroelastomer, and more preferably a fluoroelastomer of the FKM type.

The amount of elastomer is between 55% and 95% by weight relative to the total weight of the composition.

[0020] According to another embodiment, the elastomeric material is chosen from one or more thermoplastic elastomers such as polyurethane, polyether block amide, elastomeric copolyesters, acrylic elastomers or styrenic elastomers.

[0021] Yet another embodiment of the invention, the material is chosen from cold vulcanizable elastomers such as silicones.

The hardness of the elastomeric material can be chosen over a range of 20 shore OO to 90 shore D depending on the haptic and functional needs.

It is possible to produce by molding hard elements of a box with hardnesses of 90 shore D for example, while the Shore OO and Shore A materials will rather be used as a coating on a hard element. Soft parts such as bracelets will be made from Shore A hardness.

[0024] For example, in the case of a watch case, the elastomer can be sprayed onto the surface of the case and serve as a coating, or else overmolded to provide a soft feel.

[0025] According to the invention, the elastomeric material comprises thermally conductive fillers having a thermal conductivity greater than 20W.m-1.K-1, such as hexagonal boron nitride or graphene or carbon nanotubes, for example. The quantity of these thermally conductive fillers in the elastomeric material is between 0.04% and 5% by mass and make it possible to increase the thermal conductivity of the material by a factor of 3, from 0.4 to 1.2Wm-1.K-1 without for all that increase the electrical conductivity thereof. Such thermally conductive fillers have the advantage of better evacuating body heat and therefore of limiting perspiration.

According to an advantageous aspect of the invention, the elastomeric material also comprises an antibacterial additive, for example based on silver, so as to limit, or even prevent, the development of bacteria, on the surface and inside material, mainly due to the perspiration of the wearer when the bracelet is in contact with the skin for example.

[0027] Preferably, the antimicrobial additive used is Sanitized® BC A 21-41. This additive is in the form of silver encapsulated in a ceramic glass material, its resistance to high temperatures allows it to be easily added to the mixture without altering the antibacterial properties. Depending on requirements, the amount of antibacterial additive is between 0% to 2% by mass.

[0028] The elastomeric material also comprises an anti-odor agent such as, for example, zeolite (Lithofill MM) so as to absorb odors, generally this agent is in the form of a grain having a size of 0 to 10 μm. Depending on requirements, the amount of anti-odor agent is between 0% to 1% by mass. According to a variant of the invention, the zeolite can serve as a support for diffusing a perfume, the latter could for example receive one or more essential oils or one or more fragrances. Such an embodiment is particularly advantageous given the fact that the zeolite makes it possible to diffuse the perfume for a very long period of time.

[0029] The elastomeric material includes a reinforcing agent such as silica to improve its durability.

[0030] According to the invention, the elastomeric material comprises hydrophilic microfibers designed to evacuate moisture, and in particular perspiration, through the elastomeric material. In accordance with the present invention, the hydrophilic microfibers have a fineness of less than 150 mTex, which is a sufficient size to be able to transport molecules of the H2O type.

According to the invention, the hydrophilic fibers are made of a cellulosic material, and fibers of the Lyocell type such as Lenzing Tencel FCP will preferably be used.

Preferably, the composition according to the invention comprises between 0.5% and 4%, preferably between 1.5% and 3.5%, by weight of microfibers relative to the total weight of the composition. The microfibers used have a length of between 0.5 mm and 1.5mm.

The presence of these microfibers in the material makes it possible to form a network of microscopic channels, and the nanofibrils forming the microfibers conduct moisture rapidly and uniformly through the material.

In order to improve the transport of humidity through the material, the microfibers incorporated into the material are composed of short cellulosic microfibers and long cellulosic microfibers, the length of the cellulosic fibers being between 0.5mm and 1.5mm .

The composition according to the invention comprises 2% by weight of short microfibers and 1.5% by weight of long microfibers relative to the total weight of the composition.

Such a mixture of short microfibers and long microfibers with microfibers touch each other and form channels improving the diffusing power of the matrix formed by the elastomeric material and moisture can be transported by capillary action through the material and thus be evacuated .

According to the invention, the microfibers preferably have a cross section in the form of a helix to give them a larger specific surface area and therefore a faster diffusing power.

More specifically, the section of the hydrophilic fibers is in the form of a helix with n blades with n strictly greater than two, so as to provide a greater specific surface area and thus promote the evacuation of moisture.

The composition may also comprise vulcanizing or crosslinking agents specific to the elastomer, and other traditional additives commonly used by those skilled in the art in the field of elastomer-based formulations, and more particularly formulations with fluoroelastomer base.

[0040] Advantageously, the composition can comprise a dye or a pigment. Mixtures of dyes and / or pigments can also be used.

For example, titanium dioxide will be used to produce a white composition, in this case the amount of dye used is 30% by weight. In order to improve the rendering of the white color, a brightening agent is used, the latter makes it possible to rebalance the color spectrum and to provide a whiter white. The amount of brightening agent used is about 1% by weight.

In the case of a white composition, a transparent FKM type fluoroelastomer will be added in an amount of 10% by weight to improve the resistance to soiling of the composition and to improve the flexibility of the final product.

In the case of a black-colored composition, a black-colored FKM-type fluoroelastomer will be used directly. The black color can be obtained via carbon black (Grade N-660).

The material described above can be directly molded to make strands of single-material bracelets in comfortable elastomer, or else overmolded to make strands of comfortable bi-material bracelets, each strand having a first lower part in comfortable material in contact. with the skin, and an upper part in another material advantageous for its function. We can also imagine that each of the parts has a different color for purely aesthetic purposes.

Hereinafter, three examples of composition are described, each of them comprises a base which forms the elastomeric matrix in which the additives are dispersed. These examples are based on samples produced by the applicant in accordance with the invention.

For a black colored bracelet, the following composition is used:

First step (black base)

[0047] <tb> FKM <SEP> P-457 (Solvay) <SEP> 100 <tb> NC <SEP> Grade N-660 (cabot) <SEP> 22 <tb> Oil <SEP> Nafol 1822B (Sasol) <SEP> 1.5 <tb> Vulc <SEP> Drimix Kenrich (TAlC) <SEP> 3 <tb> Vulc <SEP> Luperox 101XL45 <SEP> 2.5

2nd step (mixing comfort additives in the base)

[0048] <tb> black base <SEP> According to the formula below <SEP> 100 <tb> cellulose shorts <SEP> Lenzing Tencel FCP, 0.5mm <SEP> 2 <tb> lonq cellulose <SEP> Lenzinq Tencel FCP, 1.5mm <SEP> 1.5 <tb> zeolite <SEP> Lithofill MM <SEP> 0.5 <tb> Graphene (*) <SEP> 8 to 12 layers: 3mu <SEP> 0.045 <tb> silica (*) <SEP> Aerosil 200 <SEP> 0.5 <tb> Antibacterial <SEP> Sanitized BCA21-41 <SEP> 2 <tb> (*) Graphene is here the filler chosen in order to improve the thermal conductivity of the mixture and therefore to improve the heat exchange between the skin and the bracelet.

For a bracelet of white color, the following composition is used:

1st step (neutral basis)

[0050] <tb> FKM <SEP> P-457 <SEP> 100 <tb> Oil <SEP> Nafol 1822B (Sasol) <SEP> 1.5 <tb> Vulc <SEP> Drimix Kenrich (TAlC) <SEP> 3 <tb> Vulc <SEP> Luperox 101XL45 <SEP> 2.5 <tb> silica <SEP> Aerosil 200 <SEP> 17

2nd step (mixing comfort additives in the neutral base)

[0051] <tb> Neutral base <SEP> according above formula <SEP> 100 <tb> cellulose shorts <SEP> Lenzinq Tencel FCP, 0.5mm <SEP> 2 <tb> long cellulose <SEP> Lenzing Tencel FCP, 1.5mm <SEP> 1.5 <tb> zeolite <SEP> Lithofill MM <SEP> 0.5 <tb> Boron Niter hBN (*) <SEP> 3M ™ Boron Nitride Cooling Filler Flakes CFF 500-3 and 200-3 <SEP> 5 <tb> TiO2 <SEP> TI Pure R104, dupont <SEP> 30 <tb> silica <SEP> Aerosil 200 <SEP> 0.5 <tb> Antibacterial <SEP> Sanitized BCA21-41 <SEP> 2 <tb> Optical brightener <SEP> <SEP> 1 <tb> Zinc stearate <SEP> <SEP> 0.5 <tb> FKM transparent (*) <SEP> P-957, Solvay <SEP> 10 <tb> (*) The hexagonal boron nitride is the filler chosen in order to improve the thermal conductivity of the mixture and therefore to improve the heat exchange between the skin and the bracelet. <tb> (*) The transparent FKM is added at the end of the mixture at a high shear rate in order to create a polyphase mixture (dispersion of the transparent FKM in the mixture initially produced): this technique makes it possible to improve the resistance to soiling of the white mixture and to improve its flexibility and therefore the wearing comfort.

For the bracelets having another color, the following composition is used:

1st step (neutral basis)

[0053] <tb> FKM <SEP> P-457 <SEP> 100 <tb> Oil <SEP> Nafol 1822B (Sasol) <SEP> 1.5 <tb> Vulc <SEP> Drimix Kenrich (TAlC) <SEP> 3 <tb> Vulc <SEP> Luperox 101XL45 <SEP> 2.5 <tb> silica <SEP> Aerosil 200 <SEP> 17

2nd step (mixing the additives in the neutral base)

[0054] <tb> Neutral base <SEP> according above formula <SEP> 100 <tb> cellulose shorts <SEP> Lenzinq Tencel FCP, 0.5mm <SEP> 2 <tb> lonq cellulose <SEP> Lenzing Tencel FCP, 1.5mm <SEP> 1.5 <tb> zeolite <SEP> Lithofill MM <SEP> 0.5 <tb> Boron Niter hBN (*) <SEP> 3M ™ Boron Nitride Cooling Filler Flakes CFF 500-3 and 200-3 <SEP> 5 <tb> silica <SEP> Aerosil 200 <SEP> 0.5 <tb> Antibacterial <SEP> Sanitized BCA21-41 <SEP> 2 <tb> Optical brightener <SEP> <SEP> 1 <tb> Zinc stearate <SEP> <SEP> 0.5

The piece of jewelry made of elastomeric composite material according to the invention is obtained by a process comprising the following steps: <tb> <SEP> - carrying out a preparation of a composition as described above; <tb> <SEP> - molding the composition obtained during the first step to obtain the desired shape; <tb> <SEP> - carry out the finishing steps for the molded part obtained during the second step.

According to the needs of those skilled in the art and the parts to be produced, the stages of finishing the molded part can consist of sewing, printing a pattern, making holes in the material, etc. ..

The molding of the composition can be carried out by any type of method known to those skilled in the art, such as injection molding, by extrusion or by compression.

Vulcanization is carried out in a known manner at a temperature generally between 130 ° C and 200 ° C, for a sufficient time which may vary depending on the desired part, for example between 60 and 300 seconds depending on the temperature vulcanization process, the vulcanization system adopted and the vulcanization kinetics of the composition.

The piece of jewelry may for example be a bracelet, in particular a watch strap. More specifically, a bracelet according to the invention can have particular shapes and cutouts and still meet strict specifications in terms of mechanical strength, and more specifically in terms of tensile strength, resistance to soiling, all by providing good wicking of the wearer's sweat.

[0060] Such a material to improve comfort makes it possible to manufacture timepieces or jewelry such as bracelets, bracelet buckles, necklaces, boxes, case backs, pushers, buckles or even glasses. .

Of course, the present invention is not limited to the example illustrated and is susceptible of various variants and modifications which will appear to those skilled in the art.

Claims (15)

1. Piece of jewelry made of elastomeric composite material, characterized in that the elastomeric composite material comprises an elastomeric matrix in which is dispersed between 0 and 4% by mass of cellulosic fibers, between 0 and 2% by mass of an additive antibacterial, between 0 and 5% by mass of thermally conductive fillers, between 0 and 1% by mass of anti-odor agents, and between 0 and 1% by mass of silica. 2. Piece of jewelry according to claim 1, characterized in that the elastomer is a fluoroelastomer of fluorocarbon rubber (FKM) type. 3. Piece of jewelry according to claim 1 or 2, characterized in that the composite material comprises short cellulosic fibers and long cellulosic fibers, the length of the cellulosic fibers being between 0.5mm and 1.5mm. 4. Piece of jewelry according to claim 3, characterized in that the composite material comprises between 1.5% and 3.5% by mass of microfibers, and preferably 2% by mass of short microfibers and 1.5% by mass of long microfibers relative to the total weight of the composition. 5. Piece of jewelry according to claim 1 or 2, characterized in that the elastomeric material comprises at least between 0 and 30% by weight of a coloring additive. 6. Piece of jewelry according to one of claims 1 to 5, characterized in that the elastomeric material comprises less between 0 and 1% by weight of anti-odor agents. 7. Piece of jewelry according to one of claims 1 to 7, characterized in that the elastomeric material comprises at least one mold release agent. 8. Piece of jewelry according to one of claims 1 to 7, characterized in that the elastomeric material comprises a brightening agent. 9. A method of manufacturing a piece of jewelry according to one of claims 1 to 8, characterized in that it comprises the following steps: - produce a composition comprising at least one elastomer, between 0 and 4% by mass of cellulose fibers, between 0 and 2% by mass of an antibacterial additive, between 0 and 5% by mass of thermally conductive fillers, between 0 and 1 % by mass of anti-odor agents, and between 0 and 1% by mass of silica; - Perform a molding of the composition obtained in the previous step; - carry out the finishing stages of the molded part obtained during the second stage. 10. The method of claim 9, characterized in that the elastomer is a fluoroelastomer of fluorocarbon rubber type. 11. The method of claim 9 and 10, characterized in that the composition comprises short cellulosic fibers and long cellulosic fibers, the length of the cellulosic fibers being between 0.5mm and 1.5mm. 12. Method according to one of claims 9 to 11, characterized in that the composition comprises thermally conductive fillers. 13. Method according to one of claims 9 to 12, characterized in that the composition comprises anti-odor agents. 14. Method according to one of claims 9 to 13, characterized in that the composition comprises reinforcing fillers. 15. Method according to one of claims 9 to 14, characterized in that the composition comprises at least one coloring additive.