CH716213A2 - Piece of jewelry in natural elastomer material. - Google Patents

Abstract

The invention relates to a piece of jewelry made of natural elastomeric composite material, characterized in that the natural elastomeric composite material comprises a natural elastomer matrix in which are dispersed between 0 and 6% of cellulose fibers, between 0 and 5% anti-odor agents, and between 0 and 30% silica.

Description

Field of the invention

The present invention relates to the technical field of materials based on elastomers. More precisely, the invention relates to a piece of jewelry made from a natural elastomeric material, a method of manufacturing said pieces, as well as said pieces 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 feel and their resistance.

[0004] For example, patent EP 2 468 127 discloses 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% in weight of polytetrafluoroethylene nanoparticles, relative to the total weight of the composition, at least one of said reinforcing fillers being present.

[0005] However, these elastomeric materials used for bracelets or watch components in contact with the skin are based on components coming from 90% or more of fossil resources, which does not respond to current environmental concerns. .

To respond to these environmental concerns, there are alternatives such as natural elastomers. However, the latter contain a combination of very allergenic proteins and it is therefore advisable to use natural elastomers free from these allergens. Such elastomers are for example offered by the company Yulex Corp.

[0007] Although free from allergens, this type of natural elastomer has certain drawbacks for producing pieces that are sufficiently comfortable to wear. In fact, this type of natural elastomer has a strong odor linked to the rubber and to the vulcanization method, it is also not very resistant to soiling and not very pleasant in contact with the skin.

Summary of the invention

[0008] The object of the invention is in particular to overcome the various drawbacks of these known techniques.

[0009] More precisely, an objective of the invention is to provide a piece of jewelry made from a natural elastomer material intended to be in prolonged contact with the skin (direct or indirect), and to obtain a natural elastomer material having a limited impact, see zero, on the environment, while having properties to improve the evacuation of perspiration and good resistance to aging (UV, perspiration, aesthetics, tearing, abrasion, etc ...).

[0010] 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 natural elastomeric composite material, said natural elastomeric composite material comprising a matrix in natural elastomer in which are dispersed between 0 and 6% of cellulose fibers, between 0 and 5% of anti-odor agents, and between 0 and 30% of silica.

[0011] In accordance with other advantageous variants of the invention: the natural elastomer is deproteinized natural rubber; the elastomeric material comprises a fluoroelastomer between 5 and 20%; the elastomeric composite material comprises short cellulosic fibers and long cellulosic fibers, the length of the cellulosic fibers being between 0.5mm and 1.5mm; the elastomeric material comprises at least between 5 and 10% of a coloring additive; the elastomeric material comprises at least between 0 and 2% polytetrafluoroethylene; the natural elastomeric material comprises at least one mold release agent.

The invention also and in particular relates to any timepiece made of natural elastomer 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: producing a composition comprising at least one natural elastomer and between 0 and 30% silica; add antiozonants and antioxidants; add between 0 and 6% of cellulosic fibers, and between 0 and 5% of anti-odor agents; add a fluoroelastomer in the amount of 5 to 20%; molding parts from the composition obtained in the previous step; bake the molded parts obtained for 2 hours at 120 ° C; and carry out the finishing steps for the molded part obtained.

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 natural elastomeric composite material, characterized in that the natural elastomeric composite material comprises a natural elastomer matrix in which are dispersed between 0 and 6% of cellulosic fibers, between 0 and 5 % anti-odor agents, and between 0 and 30% silica.

[0016] According to the invention, the natural elastomeric material chosen for the matrix is a hypoallergenic natural rubber, such as that manufactured by the company Yulex Corp. The amount of natural elastomer is 100% by weight relative to the total weight of the composition.

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 be used instead as a coating on a hard element. Soft parts such as bracelets will be made from Shore A hardness.

[0019] 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.

[0020] According to an advantageous aspect of the invention, the rubber naturally exhibits antibacterial properties (The latex obtained from the rubber tree contains sesquiterpenes which are naturally biocidal substances) making it possible to limit or even prevent the development of bacteria , on the surface and inside the material, mainly due to the perspiration of the wearer when the bracelet is in contact with the skin for example.

[0021] 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 5%. According to a variant of the invention, the zeolite serves as a support for diffusing a perfume, the latter may 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.

The natural elastomeric material also comprises a reinforcing agent such as silica to improve its durability and its resistance to wear, the amount of silica present is between 0% to 30%.

[0023] 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% and 6% 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.

[0027] In order to improve the transport of moisture 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 .

[0028] Such a mixture of short microfibers and long microfibers cause the microfibers to touch each other and form channels improving the diffusing power of the matrix formed by the elastomeric material and the humidity can be transported by capillary action through the material and thus be evacuated from the surface.

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 comprises vulcanizing agents specific to the elastomer, and other traditional additives commonly used by those skilled in the art in the field of rubber-based formulations. Peroxides are, for example, vulcanizing agents commonly used for rubber. The composition also comprises a vulcanization accelerator and a vulcanization retarder, respectively present in an amount of 8% and 0.5%.

[0032] Advantageously, the composition can comprise a dye or a pigment. Mixtures of dyes and / or pigments can also be used.

The composition also comprises antiozonants and antioxidants in order to protect the natural rubber from aging, the latter being respectively present in an amount of 1%.

In order to improve the color of the rubber, titanium dioxide is used to counterbalance the yellow color of natural rubber and thus obtain a composition of white color, the amount of titanium dioxide used is between 5 and 10%. Obviously other dyes, preferably natural, can be added to obtain the desired color.

A fluoroelastomer of transparent FKM type is also added in an amount of 20% to improve the resistance to soiling of the composition and to improve the flexibility of the final product.

According to one embodiment of the invention, polytetrafluoroethylene (PTFE) is also added in an amount of 0 to 2%, and more precisely in an amount of 1.84% in the material to improve the feel. This gives a softer touch on contact with the skin.

The material described above can be directly molded to make strands of mono-material bracelets based on natural elastomer, or else overmolded to make strands of bi-material bracelets, each strand having a first lower part of natural 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.

Below, two 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. <tb> Yulex Pure <SEP> 100 <SEP> 100 <tb> Stearic acid <SEP> 0 <SEP> 0 <tb> Zinc oxide <SEP> 3 <SEP> 0 <tb> Peroxide <SEP> 4 <SEP> 4 <tb> Antioxidant <SEP> 1 <SEP> 1 <tb> Anti ozonant <SEP> 1 <SEP> 1 <tb> Accelerator <SEP> 8 <SEP> 8 <tb> Self-timer <SEP> 0.5 <SEP> 0.5 <tb> Cellulose fiber <SEP> 6 <SEP> 6 <tb> precipitated silica 180 +/- 20 m2 / g <SEP> 30 <SEP> 30 <tb> TiO2 <SEP> 10 <SEP> 5 <tb> kaolin / clay <SEP> 2 <SEP> 0 <tb> Zeolite <SEP> 5 <SEP> 5 <tb> FKM <SEP> 20 <SEP> 20 <tb> PTFE <SEP> 0 <SEP> 1.84

The piece of jewelry made of elastomeric composite material according to the invention is obtained by a process comprising the following steps: producing a composition comprising at least one natural elastomer and between 0 and 30% silica; add antiozonants and antioxidants; add between 0 and 6% of cellulosic fibers, and between 0 and 5% of anti-odor agents; add a fluoroelastomer in the amount of 5 to 20%; molding or overmolding parts from the composition obtained in the previous step; bake the molded or overmolded parts obtained for 2 hours at 120 ° C; and carry out the finishing steps for the molded part obtained.

According to the needs of those skilled in the art and of 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 compression.

Vulcanization is carried out in a known manner at a temperature generally between 10 ° C and 200 ° C, for a sufficient time which may vary depending on the desired part, for example between 60 and 380 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.

Such a natural material 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 to various variants and modifications which will appear to those skilled in the art.

Claims (13)

1. Piece of jewelry made of natural elastomeric composite material, characterized in that the natural elastomeric composite material comprises a natural elastomer matrix in which are dispersed between 0 and 6% of cellulosic fibers, between 0 and 5% of anti- odors, and between 0 and 30% silica. 2. Piece of jewelry according to claim 1, characterized in that the natural elastomer is a rubber. 3. Piece of jewelry according to claim 1 or 2, characterized in that the elastomeric material comprises a fluoroelastomer between 5 and 20%. 4. Piece of jewelry according to claim 1 to 3, 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. 5. Piece of jewelry according to one of claims 1 to 4, characterized in that the elastomeric material comprises at least between 5 and 10% of a coloring additive. 6. Piece of jewelry according to one of claims 1 to 5, characterized in that the anti-odor agent is zeolite. 7. Piece of jewelry according to claim 6, characterized in that the zeolite serves as a support for diffusing a perfume or an odor, the zeolite being able to receive at least one essential oil, and / or at least one fragrance. 8. Piece of jewelry according to one of claims 1 to 7, characterized in that the elastomeric material comprises less between 0 and 2% of polytetrafluoroethylene. 9. Piece of jewelry according to one of claims 1 to 8, characterized in that the natural elastomeric material comprises at least one mold release agent. 10. A method of manufacturing a piece of jewelry according to one of claims 1 to 9, characterized in that it comprises the following steps: - producing a composition comprising at least one natural elastomer and between 0 and 30% silica; - add antiozonant and antioxidant agents; - add between 0 and 6% of cellulosic fibers, and between 0 and 5% of anti-odor agents; - add a fluoroelastomer up to 20%; - molding parts from the composition obtained in the previous step; - bake the molded parts obtained for 2 hours at 120 ° C; and - carry out the finishing steps for the molded part obtained. 11. The method of claim 10, characterized in that the elastomer is a rubber. 12. Method according to claims 10 or 11, characterized in that the composition comprises at least one coloring additive. 13. Method according to one of claims 10 to 12, characterized in that the composition comprises at least one mold release agent.