CH720326A2 - Composition for decorations of a decorative element of a timepiece, piece of jewelry or a fashion item - Google Patents

Abstract

The invention relates to a composition for decorations (20) of a trim element (10) of a timepiece, piece of jewelry or a fashion item, characterized in that it comprises luminescent pigments, a thermochromic coloring material, and a polymeric binder, the thermochromic coloring material being chosen so that when its temperature increases, its optical transmission coefficient decreases, and so that when its temperature decreases, its optical transmission coefficient optical transmission increases, that is to say its opacity decreases.

Description

Technical field of the invention

[0001] The invention relates to decorations in the field of watchmaking, jewelry or jewelry, and more generally manufactured goods. The present invention relates more particularly to a composition for decorating a decorative element of a timepiece, piece of jewelry or a fashion item.

[0002] In the present text, the terms “decorating element” designate, in a manner commonly accepted in the aforementioned fields, an element visible to a user, and having a particularly decorative function, that is to say contributing to the visual appearance of an object.

Technology background

[0003] Luminescent inks and paints, that is to say comprising luminescent pigments, are widely used in particular in the field of watchmaking, for decorative and/or functional purposes, in order to be able to visualize a decoration, on a decorative element of a timepiece in a dark environment.

[0004] Furthermore, in order to increase the visual attractiveness of the decorations of the elements used to decorate timepieces, coloring materials can be added to the luminescent inks and paints in order to be able to visualize them, when the ambient light level allows it. , that is to say in a bright environment, for example during the day, colors on the decorations of the covering elements.

[0005] In summary, the aim is to obtain decorations that are both visible in a dark environment and present one or more attractive colors in a bright environment.

[0006] One of the disadvantages of these decorations is that they do not adapt to the needs of the user. In particular, depending on the season, the level of ambient light and the duration of exposure to these light levels vary considerably. In particular, the level of ambient light is generally much higher in summer than in winter, as is the length of days. In winter, a user will therefore expect the decor to be more easily and longer visible in a dark environment than in summer.

However, when the light intensity of the decor is favored, it is difficult to obtain intense colors visible in a luminous environment, particularly for dark colors, which can be detrimental to the attractiveness of the decor in summer.

[0008] There is therefore a need to provide a decoration of a covering element whose appearance adapts to the season during which the timepiece is worn in order to present an attractive appearance whatever the level of ambient brightness.

Summary of the invention

[0009] To this end, the present invention relates to a composition for decorating a decorative element of a timepiece, piece of jewelry or a fashion item, comprising luminescent pigments, a material thermochromic dye, and a polymeric binder, the thermochromic dye material being chosen so that when its temperature increases, its optical transmission coefficient decreases, and so that when its temperature decreases, its optical transmission coefficient increases.

[0010] The thermochromic coloring material advantageously has a colored appearance when its temperature is higher than a predetermined value, in particular when it is present in an environment whose temperature is high, for example from 20° C., and presents a transparent appearance when its temperature is below a predetermined threshold, in particular when it is present in an environment whose temperature is low, for example below 10°C.

[0011] Thus, the thermochromic coloring material is visible in an environment having a high temperature, which is advantageously mainly the case when the environment is bright. Conversely, the visibility of the luminescent pigments is not impacted by the thermo-chromic coloring material in an environment whose temperature is low, which is advantageously mainly the case when the environment is dark.

[0012] It should be noted that, in the present text, the terms “coloring material” are used to designate any coloring substance, such as a pigment dye or a soluble dye. Therefore, the terms “coloring material” mean a pigment dye, a soluble dye or the combination of a pigment dye and a soluble dye, whether or not in combination with non-coloring substances.

[0013] In particular embodiments, the invention may also include one or more of the following characteristics, taken in isolation or in all technically possible combinations.

[0014] In particular embodiments, the proportion by mass of the luminescent pigments is greater than the sum of the proportions by mass of the other components.

[0015] In particular embodiments, the composition for decorations comprises an additional coloring material whose mass proportion is less than or equal to 10%, or even less than or equal to 5%.

[0016] In particular embodiments, the additional coloring material has a color identical to that of the thermochromic coloring material.

[0017] In particular embodiments, the additional coloring material has a shade different from that of the thermochromic coloring material.

[0018] In particular embodiments, the mass proportion of thermochromic coloring material is less than or equal to 0.5%.

[0019] In particular embodiments, the proportion by mass of luminescent pigments is greater than or equal to 60% by mass, or even 70% by mass.

[0020] In particular embodiments, the composition comprises a binder and one or more additives chosen so that the composition has a solid form. Thus, the composition can be molded in the final form or in the form of a raw material intended to be machined, etc.

[0021] In particular embodiments, the composition comprises a binder and one or more additives chosen so that the composition has a liquid form. Thus, the composition can be applied in the form of decoration by spraying, screen printing, pad printing or any other method within the reach of those skilled in the art.

[0022] In another aspect, the present invention also relates to a covering element for a timepiece, piece of jewelry or a fashion item, comprising a substrate provided with a surface visible on all or part of which extends a decoration formed by a layer of a composition as described above.

[0023] Another aspect of the invention relates to a decorative element of a timepiece, piece of jewelry or a fashion item, which comprises a substrate provided with a surface visible on all or part of which extends a decoration formed by a composition as described above, said decoration being in the form of a stack of thin layers comprising a base layer comprising luminescent pigments and an upper layer superimposed on the base layer, comprising the thermo-chromic coloring material and the polymeric binder.

Brief description of the figures

Other characteristics and advantages of the invention will appear on reading the following detailed description given by way of non-limiting example, with reference to the appended drawings in which Figures 1 and 2 schematically represent a section view of a covering element in two embodiments, comprising a decoration according to the invention.

Note that the figures are not necessarily drawn to scale for reasons of clarity.

Detailed description of the invention

The present invention relates to a composition for a decoration 20 of a trim element 10 of a timepiece, piece of jewelry or a fashion item, as schematically represented in Figures 1 and 2 in exemplary embodiments.

In particular, the covering element 10 comprises a substrate 11 provided with a visible surface 110 over all or part of which the decoration 20 extends.

[0028] In the application of the invention to the field of watchmaking, the trim element 10 can constitute a bezel, a middle part, a dial, a wall light, a hand, a crown, a pusher or any other visible element of the timepiece.

[0029] The composition advantageously comprises luminescent pigments adapted to emit light when the covering element 10 is in a dark environment, a thermo-chromic coloring material having an optical transmission coefficient capable of varying according to the temperature of said material thermo-chromic dye, that is to say according to the temperature of the environment in which the covering element 10 is located, and a polymeric binder and one or more additives making it possible in particular to bind together the luminescent pigments and the thermo-chromic coloring material.

[0030] In particular, the luminescent pigments are capable of emitting light after having been exposed to light radiation of a certain wavelength range, typically wavelengths corresponding to ultraviolet and the visible range. These luminescent pigments are known per se to those skilled in the art.

[0031] Furthermore, the optical transmission coefficient of the thermochromic coloring material is capable of changing reversibly depending on the temperature of the thermochromic coloring material, such that when it increases, its optical transmission coefficient decreases, that is, its opacity increases, and so that when it decreases, its optical transmission coefficient increases, that is, its opacity decreases.

[0032] For example, when the temperature of the environment in which the covering element is located is high, for example above 20° C., the thermo-chromic coloring material is opaque such that it is capable of absorbing all or part of the light potentially emitted by the luminescent pigments. On the contrary, when the temperature of the environment is low, for example below 10°C, the thermo-chromic coloring material is transparent such that it is capable of transmitting all or part of the light potentially emitted by luminescent pigments. When the temperature of the environment is average, that is to say between 10°C and 20°C, the thermo-chromic coloring material is for example semi-transparent.

It should be noted that it is obvious that when the thermochromic coloring material is opaque, it is still transparent to radiation in the range of certain wavelengths, for example in the range of ultraviolet, in order to allow the excitation of the luminescent pigments of the base layer 21.

[0034] It is also possible to choose a thermochromic material capable of occupying only two states, a transparent state and an opaque state, respectively depending on whether the temperature of the environment is below or beyond a predefined value, for example 15°C.

[0035] It should be noted that the relative terms “high”, “low” and “medium”, as well as the temperature ranges which are respectively associated with them, are only mentioned for illustrative purposes, in order to facilitate the understanding of the 'invention.

[0036] We understand here that, when the thermochromic coloring material is opaque, its color is visible, which makes it possible to intensify the color of the decoration 20, and that when the thermochromic coloring material is transparent, it transmits the all of the light emitted by the luminescent pigments, which promotes the visibility of the decor in a dark environment.

Preferably, the thermo-chromic coloring material comprises a leuco-dye. The operating temperature range of the thermochromic coloring material, and therefore of the timepiece comprising the covering element 10, can extend from -15°C to 60°C.

Preferably, the proportion by mass of the luminescent pigments is greater than the sum of the proportions by mass of the other components, that is to say at least the thermochromic coloring material and the polymeric binder. This characteristic advantageously makes it possible to provide a decoration 20 having an attractive appearance thanks to the presence of a color which can be intense, that is to say saturated, when the temperature level of the decoration 20 is greater than a threshold value, for example summer, and emitting a high level of light when the temperature level of the decoration 20 is below a threshold value, for example winter.

[0039] Thus, the present invention makes it possible to obtain a decoration whose appearance adapts depending on the season during which the timepiece is worn in order to present an attractive appearance whatever the level of ambient light.

[0040] In other words, during the summer season, the environment is mainly luminous and the decor 20 presents intense colors, and during the winter season, the environment is mainly dark or dimly luminous and the decor presents excellent visibility.

[0041] Advantageously, the polymeric binder is transparent so as not to affect the color of the decoration 20 when the temperature of the environment allows the thermo-chromic dye to be seen, that is to say when the temperature of the environment is medium or high, and not to affect the intensity of the light emitted by the decor 20 when the temperature of the environment is low.

The decoration 20 preferably comprises an additional coloring material whose mass proportion is less than or equal to 10%, for example less than 5%, preferably less than 1%. This additional coloring material thus makes it possible to increase the intensity, that is to say the saturation, of the color of the visible decoration, while having a negligible impact on the intensity of the light that can be emitted by the luminescent pigments. when the environmental temperature is low.

[0043] By way of example, the additional coloring material may advantageously comprise an optical brightener in order to exhibit fluorescence making it possible to increase the intensity of the color of the decoration 20, while increasing the intensity of the light that can be emitted . Advantageously, the additional coloring material makes it possible to modify the color of the decoration 20 visible when the environment has a low temperature, so that it is attractive.

[0044] In one embodiment of the invention, the additional dye system has a shade identical to that of the thermochromic dye system. Thus, the color of the decoration 20 is even more saturated when the temperature of the environment allows the thermo-chromic dye to be seen.

Alternatively, in another embodiment of the invention, the additional coloring material has a shade different from that of the thermochromic coloring material. Thus, the color of the decoration 20 can change slightly depending on the temperature of the environment. In particular, when the environment has an average or high temperature, the color of the decoration 20 is representative of a mixture of the shades of the thermo-chromic coloring material and the additional coloring material, the shade of the thermo-chromic coloring material being less visible in said mixture when the environmental temperature is low than when it is high.

Preferably, the decoration composition 20 comprises a mass proportion of thermochromic coloring material less than or equal to 0.5%, or even less than or equal to 0.1%. Furthermore, the proportion by mass of luminescent pigments is greater than or equal to 60%, or even 70% by mass.

[0047] These characteristics contribute to increasing the intensity of the light that the decoration 20 is likely to emit, and consequently, contribute to increasing its visibility when the temperature of the environment is low, while ensuring high saturation of its color when the environmental temperature is medium or high.

Advantageously, the thermochromic coloring material is chosen from the following groups: spiropyrans, quinones, thiazines, oxazines, phenazines, phthalides or fluoranes.

[0049] In one embodiment of the invention, the composition for decorations 20 according to the invention comprises a binder and one or more additives chosen so that the composition has a solid form. For example, the decoration composition 20 may comprise a resin based on thermoplastics, silanes, phosphorescent pigments, fluorescent pigments, dyes, silica and ceramic powder.

[0050] Thus, the composition is in the form of a raw material intended to be shaped in order to produce decorations 20. In particular, the raw material is machined in order to obtain a part which is glued to a surface of the covering element 10 in order to form the decoration 20. It is also possible to obtain parts by overmolding, multi-injection or by extrusion to form the decorations 20.

[0051] In this embodiment of the invention, the decorations 20 can be formed by appliques intended to be fixed on a dial, a bezel, etc.

[0052] In another embodiment of the invention, the composition for decorations 20 according to the invention comprises a binder and one or more additives chosen so that the composition has a liquid form. For example, the decorative composition 20 may comprise an epoxy-based resin, silanes, phosphorescent pigments, fluorescent pigments, dyes, silica and ceramic powder.

[0053] Thus, the composition can be deposited by spraying, applied with a brush or deposited in the form of a drop. In this embodiment, the decoration 20 requires drying time to allow it to solidify once it is deposited.

[0054] In this embodiment of the invention, the decorations 20 can be formed by a coating intended to be deposited on a dial, hands, a bezel, etc.

[0055] In yet another embodiment of the invention, the decoration 20 is in the form of a stack of thin layers comprising a base layer 21 comprising the luminescent pigments and an upper layer 22 superimposed on the base layer 21, comprising the thermo-chromic coloring material and the polymeric binder. Optionally, the upper layer 22 may include additional coloring material.

[0056] It should be noted that when it is opaque to all or part of the visible light to reveal the color of the decoration 20, the upper layer 22 is transparent to radiation, particularly in the ultraviolet range, in order to allow the excitation of the luminescent pigments of the base layer 21.

[0057] These thin layers can be deposited by casting, by spraying, by thermoforming, by spraying, by welding, etc.

[0058] More generally, it should be noted that the modes of implementation and embodiment considered above have been described by way of non-limiting examples, and that other variants are therefore possible.

[0059] In particular, it is also possible for the composition according to the invention to comprise several additional dyes, for example having respectively a shade identical to that of the thermochromic coloring material and a different shade.

Claims (11)

1. Composition for decorations (20) of a decorative element (10) of a timepiece, piece of jewelry or a fashion item, characterized in that it comprises luminescent pigments, a thermochromic coloring material, and a polymeric binder, the thermochromic coloring material being chosen so that when its temperature increases, its optical transmission coefficient decreases, and so that when its temperature decreases, its optical transmission coefficient increases . 2. Composition for decorations (20) according to claim 1, in which the proportion by mass of the luminescent pigments is greater than the sum of the proportions by mass of the other components. 3. Composition for decorations (20) according to claim 1 or 2, comprising an additional coloring material whose proportion by mass is less than or equal to 10%. 4. Composition for decorations (20) according to claim 3, in which the additional coloring material has a shade identical to that of the thermo-chromic coloring material. 5. Composition for decorations (20) according to claim 3, in which the additional coloring material has a shade different from that of the thermo-chromic coloring material. 6. Composition for decorations (20) according to one of claims 1 to 5, in which the proportion by mass of thermo-chromic coloring material is less than or equal to 0.5%. 7. Composition for decorations (20) according to claim 1 to 6, in which the proportion by weight of luminescent pigments is greater than or equal to 60% by weight. 8. Composition for decorations (20) according to one of claims 1 to 7, comprising one or more additives, the polymeric binder and the additive(s) being chosen so that the composition has a solid form. 9. Composition for decorations (20) according to one of claims 1 to 8, comprising one or more additives, the polymeric binder and the additive(s) being chosen so that the composition has a liquid form. 10. Decorative element (10) of a timepiece, piece of jewelry or a fashion item, comprising a substrate (11) provided with a visible surface (110) on all or part of which extends a decoration (20) formed by a layer of a composition according to one of claims 1 to 9. 11. Decorative element (10) of a timepiece, piece of jewelry or a fashion item, comprising a substrate (11) provided with a visible surface (110) on all or part of which extends a decoration (20) formed by a composition according to one of claims 1 to 7, said decoration (20) being in the form of a stack of thin layers comprising a base layer (21) comprising the pigments luminescents and an upper layer (22) superimposed on the base layer (21), comprising the thermo-chromic coloring material and the polymeric binder.