WO2018054995A1 - Item at least partially coated with at least one layer of luminescent coating - Google Patents

Abstract

The invention relates to an item comprising a substrate at least partially coated with at least one layer of a luminescent coating having a thickness greater than 30 microns.

Description

 ARTICLE COVERED AT LEAST PARTIALLY BY AT LEAST ONE LUMINESCENT COATING LAYER

 The present invention relates to the manufacture of various luminescent articles and the articles thus produced.

 It has already been proposed to use phosphorescent materials on containers for receiving liquids.

 US 2004/0064989 discloses a container for receiving a drink, which is affixed a decorative phosphorescent coating in the form of adhesive phosphorescent film. The possibility of introducing pigments into the mass before molding the container is mentioned, but in practice such incorporation poses many problems.

 CN 104417845 discloses a bottle of wine coated with a coating of a phosphorescent material. A sieve of 250-400 mesh is mentioned, which involves the use of small luminescent pigments.

 CN 102133977A teaches to screen a phosphorescent composition on a glass. The composition can be deposited by screen printing using a 100 mesh screen, which corresponds to a little less than 150 microns sieve size. No information is given on the thickness of the deposit or the size of the luminescent pigments. The screen must pass the pigments, which must be much smaller particle size. As a result, in this prior application, the size of the luminescent pigments is much less than 150 microns.

 No. 1,637,963 describes a phosphorescent varnish based on zinc sulphide. The matrix may be colored by introducing a dye such as aniline.

 It is known from application EP 0 540 390 to mix glass beads and pigments to obtain a luminescent coating, dedicated in particular to coatings, for example of soil, which must be guaranteed a long service life.

 The invention aims to further improve the production of luminescent areas on an article, for decoration or other purposes.

The invention seeks in particular to have, if desired, a lasting effect of remanence in the case of phosphorescence and to have solutions compatible with the coating application technologies that are lacquering, screen printing, enamelling or dusting. By "luminescence" it is understood in the sense of the present invention any phenomenon of photoluminescence, that is to say, re-emission of light after a light excitation, the photons being emitted following electronic transitions. It includes fluorescence and phosphorescence, the latter corresponding to a residual emission of light by the material after being illuminated. It does not include chemiluminescence or bio-luminescence phenomena, where the light is emitted by chemical oxidation reactions, for example, or biological reactions, which have the disadvantage of not being able to "recharge" the light. luminescent element simply by exposing it to a light source, visible or not, as the case may be. It also does not include luminescent elements where excitation is substantially produced by ionizing radiation. Thus, the luminescence according to the invention is not produced using a radioactive element, and an article according to the invention does not contain radium. Preferably, the luminescent producing compound (s) are in the invention purely mineral. The luminescence may be green or yellow in color or in a color other than green and yellow, for example white, blue, orange or violet.

 Article coated

 According to a first aspect, the invention relates to an article comprising a substrate at least partially covered by at least one layer of a luminescent coating whose thickness is greater than 30 microns, better at 50 microns, more preferably at 80 microns , always better at 100 microns, even better at 150 microns, preferably between 150 and 1500 microns.

 The fact of depositing a large thickness of coating allows it to contain luminescent grains of relatively large size, which has multiple advantages.

 First, larger grains may have stronger luminescence and longer duration if phosphorescence occurs. Moreover, it makes it easier to color the grains to give the coating a color in the visible and above all it makes it possible to color the luminescence light more easily, and thus to obtain interesting effects of color changes visible light / color of the light. luminescence.

In addition, the relatively large coating thickness makes it possible to increase the thickness of the matrix which links the grains to the substrate and thus to improve the mechanical strength of the coating. This also helps to get when the coating thickness is greater than the thickness of the pigment grains a smooth coating, which may be desirable for many applications.

 The luminescent coating may be fluorescent. Preferably, the luminescent coating is phosphorescent.

 The luminescent coating is preferably of a thickness of between 30 and

1500 microns, better 50 and 900 microns, even better 100 and 900 microns, for example between 100 and 800 microns. The luminescent charge can be evenly distributed in this thickness.

 The coating may comprise luminescent grains, in particular phosphorescent, of size between 15 and 400 microns, better still between 30 and 300 microns, and still more preferably between 30 and 180 microns.

 The coating may comprise a luminescent charge comprising a mixture of luminescent grains, in particular phosphorescent grains, having different sizes, preferably average mass sizes D 50 which differ from each other by more than 30%, taking as a reference the grains of smallest size. .

 The use of a mixture of grains of different sizes makes it possible to reduce the rasterization effect of the emitted light without having to use an excessively high proportion of grains of high size, while having a significant duration of remanence.

 The coating comprises, for example, a phosphor charge comprising a mixture of a first luminescent pigment, in particular a phosphorescent pigment, of a size of between 30 and 70 microns, of a second luminescent pigment, especially a phosphorescent pigment, of a size of between 70 and 110 microns, and a third luminescent pigment, especially phosphorescent, of size between 130 and 170 microns, each of the three pigments preferably representing between 20 and 40% by weight of the filler.

 The size of a pigment is defined as the mass size D50.

The coating may comprise a luminescent charge comprising at least one phosphor-based pigment based on alkaline earth aluminate doped with one or more rare earths.

The coating may comprise a phosphor charge comprising at least one composite phosphorescent pigment comprising a grain of a phosphorescent material, especially a rare earth aluminate, at least partially covered by smaller grains of a metal oxide, in particular ferrous or non-ferrous oxide. , having when not ferrous material preferably a decomposition temperature greater than or equal to 550 ° C, better 600 ° C when the pigment must be compatible with enamelling. Metallic oxides, in particular ferrous or non-ferrous, make it possible to color the pigments and to act on the luminescence color.

 The size of the oxide (s) metal (s), including non-ferrous, may be less than or equal to 1 micron.

 The mass proportion of the grains of metal oxide (s) may be less than or equal to 1% within the luminescent charge.

 Preferably, the coating comprises a transparent matrix.

 Examples of luminescent pigments that can be used are the composite pigments described in the French patent application FR 1559270, and in particular those defined by the wording of claim 1 of the application as filed, which is incorporated herein by reference.

 The substrate may be glass, metal, plastic or a material of plant or animal origin, including wood.

 The article may be a container, a lamp, a tableware item, a signaling device, among others.

 The coating can be formed in different ways on the article, in particular by lacquering, screen printing, enameling, dusting.

 Lacquering composition

 The subject of the invention is, according to another of its aspects, independently or in combination with the foregoing, a luminescent lacquering composition comprising, by dry weight relative to the total weight of the composition:

 between 30 and 75% of a luminescent charge, better more than 50%, between 25 and 50% of a binder, preferably transparent.

 Such a composition makes it possible to obtain a strong luminescence, with regard to the concentration of luminescent charge, and allows the realization of a coating as defined above.

 The binder may be based on polyurethane.

The composition preferably comprises between 0.5 and 2% by dry weight of gelling agent. This makes it possible to obtain a better hold of the composition on the substrate on which it is sprayed, while waiting for the composition to dry. Preferably, the filler has a particle size of between 30 microns and 400 microns, better still between 30 and 300 microns, more preferably between 30 and 200 microns.

 Preferably, in order to avoid the pixelation phenomenon, the phosphor charge comprises a mixture of at least two luminescent pigments, in particular phosphorescent pigments, of different particle sizes, preferably differing from each other by at least 30%, taking as a reference the most granulometry. low.

 Preferably, the phosphor charge thus comprises a mixture of a first luminescent pigment, especially a phosphorescent pigment, of between 30 and 70 microns in size, of a second luminescent pigment, especially a phosphorescent pigment, of size between 70 and 110 microns, and a third luminescent pigment, especially phosphorescent, of size between 130 and 170 microns, each of the three pigments preferably representing between 20 and 40% by weight of the filler. The luminescent charge may comprise a mixture of at least two luminescent pigments, in particular phosphorescent, of different particle sizes, preferably differing from each other by at least 30%, taking as a reference the smallest particle size.

 The luminescent charge may comprise at least one phosphor-based pigment based on alkaline earth aluminate doped with one or more rare earths.

 The luminescent charge may comprise at least one composite phosphorescent pigment comprising a grain of a phosphorescent material, especially an alkaline earth aluminate doped with one or more rare earths, at least partially covered by smaller grains of a coloring agent, for example a metal oxide, ferrous or non-ferrous. Preferably, the coloring agent is chosen to withstand the baking temperature of the composition, for example around 200 ° C.

 When the coloring agent is particulate, the size of the coloring agent grains, and in particular of the metal oxide (s), may be less than or equal to 1 micron.

 The mass proportion of the coloring agent, and in particular the grains of metal oxide (s), may be less than or equal to 1% within the luminescent charge.

According to another of its aspects, the subject of the invention is also a process for lacquering a substrate, in particular made of glass, comprising spraying the substrate with a composition as defined above so as to obtain after cooking a deposit thickness greater than 30 microns, preferably a thickness between 100 and 600 microns, better between 200 and 400 microns.

 If necessary, the substrate is treated in several passes, which can increase the thickness of the coating formed.

 Depending on the desired surface condition, an application of a lacquer without phosphorescence can be carried out on the already formed deposit containing the phosphor charge.

 Luminescent enameling composition

 The invention further relates, in another of its aspects, independently or in combination with the foregoing, to a composition comprising a colorless transparent glass flux and a luminescent charge comprising at least one luminescent pigment, in particular phosphorescent pigment.

 Such a composition, by the use of a colorless transparent flux reduces the absorption of excitation light or re-emits and contributes to obtaining a high afterglow in the case of a phosphorescent pigment.

 Such a composition is thus particularly suitable for producing a coated article as defined above, according to the first aspect of the invention.

 Preferably, the glass flux consists of glass microbeads.

 The particle size of the flux may be between 100 and 200 microns. The proportion by dry weight of the phosphor load is preferably between 35 and 55% relative to the total weight of the composition, better still between 40 and 50%.

 The proportion by dry weight of the flux is preferably between 35 and 55% relative to the total weight of the composition, more preferably between 40 and 50%.

 The luminescent charge preferably comprises a mixture of at least two luminescent pigments, in particular phosphorescent pigments, of different particle sizes, preferably differing from each other by at least 30%, taking as a reference the smallest particle size. This allows to obtain a strong luminescence while reducing the pixelation effect, as mentioned above.

In particular, the luminescent charge may comprise a mixture of a first luminescent pigment, especially phosphorescent, of size between 30 and 70 microns, a second luminescent pigment, in particular phosphorescent, of size between 70 and 110 microns, and a third luminescent pigment, in particular phosphorescent, of size between 130 and 170 microns, each of the three pigments preferably representing between 20 and 40% by weight of the filler.

 The luminescent charge may comprise at least one phosphor-based pigment based on alkaline earth aluminate doped with one or more rare earths.

 The phosphorescent charge may comprise at least one composite phosphorescent pigment comprising a grain of a phosphorescent material, in particular an alkaline earth aluminate doped with one or more rare earths, at least partially covered by smaller grains of a non-ferrous metal oxide. , having a decomposition temperature greater than or equal to 550 ° C, more preferably 600 ° C.

 The size of the non-ferrous metal oxide (s) grains is preferably less than or equal to 1 micron.

 The mass proportion of the grains of metal oxide (s) may be less than or equal to 1% within the luminescent charge.

 The subject of the invention is also a process for enameling a substrate, comprising the application of the enameling composition according to the invention as defined above on the substrate and the firing of the composition at a sufficient temperature. to cause melting of the flux, especially a temperature greater than or equal to 550 ° C, better than or equal to 600 ° C.

 The enameling composition may be deposited by screen printing or otherwise on the substrate, for example by spraying.

 Silkscreen composition

 The invention further relates, in another of its aspects, independently or in combination with the foregoing, to a composition intended for screen printing application, comprising a two-component resin, in particular an epoxy resin, and a luminescent charge, in particular phosphorescent, in a mass proportion by dry weight greater than or equal to 50% relative to the total weight of the composition, better still between 50 and 75% by dry weight.

 Such a composition is suitable for producing a coated article as defined above.

The luminescent charge may comprise a mixture of at least two luminescent pigments, in particular phosphorescent pigments, of different particle sizes, preferably differing from one another by at least 30%, taking as a reference the most granulometry. low. This reduces the pixelation effect while having intense luminescence, as mentioned above.

 The phosphor charge preferably comprises a mixture of a first luminescent pigment, in particular a phosphorescent pigment, ranging in size from 30 to 70 microns, a second luminescent pigment, especially a phosphorescent pigment, of size between 70 and 110 microns, and a phosphorescent phosphor. third luminescent pigment, especially phosphorescent, of size between 130 and 170 microns, each of the three pigments preferably representing between 20 and 40% by weight of the filler.

 The phosphor charge preferably comprises at least one phosphor-based pigment based on alkaline earth aluminate doped with one or more rare earths.

 The phosphor charge preferably comprises at least one phosphorescent composite pigment comprising a grain of a phosphorescent material, in particular an alkaline earth aluminate doped with one or more rare earths, at least partially covered by smaller grains of a coloring agent. , especially a ferrous or non-ferrous metal oxide.

 The coloring agent is preferably chosen to withstand the baking temperature of the composition, for example about 160 ° C.

 The size of the oxide (s) metal (s) is preferably less than or equal to 1 micron.

 The mass proportion of the grains of metal oxide (s) is preferably less than or equal to 1% within the luminescent charge.

 The invention also relates, in another of its aspects, to a process for the application by screen printing of an enameling composition or a screen printing composition as defined above, the screen printing being performed with a screen having 40 to 80 threads / cm and with a capillary film 100 to 900 microns thick, better 300 to 9700 microns, more preferably 300 to 700 microns.

 Luminescent composition with reduced pixelation effect

The invention further relates, independently or in combination with the foregoing, to a luminescent composition, in particular a phosphorescent composition, comprising a luminescent charge comprising a mixture of at least two luminescent pigments, in particular phosphorescent, of different particle sizes, preferably differing from each other by at least 30%, taking as a reference the smallest particle size.

 Such a composition makes it possible, as explained above, to use large, particularly luminescent pigments, while reducing the rasterization effect.

 Preferably, the phosphor charge comprises a mixture of a first luminescent pigment, especially phosphorescent, preferably of size between 30 and 70 microns, of a second luminescent pigment, especially phosphorescent pigment, preferably of size between 70 and 110 microns , and a third luminescent pigment, especially phosphorescent, preferably of size between 130 and 170 microns, each of the three pigments preferably representing between 20 and 40% by weight of the filler.

 Preferably, the phosphor charge comprises at least one phosphor-based pigment based on alkaline earth aluminate doped with one or more rare earths.

 Preferably, the luminescent charge comprises at least one composite phosphorescent pigment comprising a grain of a phosphorescent material, especially an alkaline earth aluminate doped with one or more rare earths, at least partially covered by smaller grains of a metal oxide. ferrous or non-ferrous, having when non-ferrous preferably when an enameling application is referred, a decomposition temperature greater than or equal to 550 ° C, more preferably 600 ° C.

 The size of the oxide (s) metal (s) may be less than or equal to 1 micron.

 The mass proportion of the grains of metal oxide (s) is preferably less than or equal to 1% within the luminescent charge. This makes it possible to color without unduly impairing the luminescence.

 The composition may comprise when it is an enameling composition a flux or a binder capable of constituting after baking or drying a transparent matrix.

 The luminescent charge may comprise a mixture of luminescent pigments of different remanence times.

 Article with images at the landmark

Another subject of the invention, according to another of its aspects, independently or in combination with the foregoing, an article, in particular a containing, comprising a body made of a transparent material, in particular glass, having two opposite faces, coated with respective images each formed with a phosphorescent coating, in particular with the aid of a composition according to the invention as defined above, the images being applied with respect to each other.

 This can provide particularly attractive effects, including giving an impression of depth to the observer.

 Luminous Illuminated Article Article

 The subject of the invention is, according to another of its aspects, independently or in combination with the foregoing, an article, in particular a container, comprising a body made of a transparent material, in particular glass, having a face on which is printed a non-luminescent image, and having a luminescent coating at least partially covering the image, the latter being observable from an opposite face of the article through said body, the luminescent coating being in particular made using a composition according to the invention as defined above.

 Multilayer removal process

 The invention also relates, independently or in combination with the foregoing, to a process for producing a luminescent coating, in particular a phosphorescent coating, on a substrate, in which at least a first layer and then a second layer are successively deposited on the substrate, the first layer comprising a luminescent charge comprising a luminescent pigment of a first average size, and the second layer comprising a luminescent pigment of a second average size less than the first.

 The deposition of the second layer smooths the first, while providing luminescence and decreasing the pixelation effect.

 More than two layers can be deposited successively, including three layers or more.

 Use of ultraviolet radiation

The subject of the invention is also, independently or in combination with the foregoing, a method for producing a phosphorescent, in particular phosphor coating, on a substrate, in which at least one layer of a substrate is deposited. a luminescent coating, and wherein ultraviolet (UV) radiation is used to polymerize the substrate coated with the at least one layer.

 In this case, the luminescent coating may be a composition in the form of an ink or a powder, in particular printed by screen printing.

 The use of UV radiation allows a long afterglow and obtaining a satisfactory finish, especially for screen printing.

 In the drying mechanism, UV radiation can initiate the reaction of photoinitiators in the formulation of the compositions.

 The UV wavelengths chosen for polymerizing the substrate are advantageously between 200 and 400 nanometers.

 Examples

 Example 1

 An aqueous lacquering composition is prepared by mixing (mass proportions) 60% of phosphorescent filler consisting of luminescent composite pigments as described in the French patent application FR 1559270, based on rare earth aluminates stained with metal oxides. % of binder PU for lacquering, and 0.5%> of a viscosity providing agent, the remainder being demineralised water.

 The charge comprises 1/3 luminescent pigments of 150 microns in average size, 1/3 of 100 micron luminescent pigments and 1/3 of 50 micron luminescent pigments.

 The composition is sprayed on glass containers to obtain a dry thickness of 300 microns and the containers thus coated are cured in an oven.

 Phosphorescent containers having a smooth coating having a persistence of more than six hours are obtained without pixelation effect.

 Example 2

A screen printing composition is prepared with the same pigment load as in Example 1, by mixing it with a two-component epoxy resin for screen printing, the rate of hardener having been doubled compared with the usual recommendation. The filler constitutes 60% by weight of the composition, by dry weight. The composition is screen printed onto a glass container using a screen having 60 threads per cm and a capillary film 500 microns thick. The pattern was computer generated.

 The baking is then carried out at 160 ° C. to initiate the polymerization.

A pattern-reproducing container is obtained, which appears luminescent at night, with no raster effect, and with a persistence of more than six hours.

 Example 3

 An enameling composition is prepared with the same phosphorescent filler as in Examples 1 and 2, at a level of 45% by weight. It is mixed with a flux consisting of transparent and colorless glass microbeads, also 45%. 10% of conventional enamel binder is added in the aqueous phase.

 The size of the glass microbeads is 150 microns.

 The composition is deposited on a glass and the enamel is baked at 600 ° C.

 We obtain a phosphorescent enamelled article, without pixelation effect, and with a strong mechanical strength of the enamel.

 The luminescence lasts more than six hours.

 Example 4

 A monochrome image with a non-luminescent ink is printed by screen printing on one side of a bottle. Then, a lacquering composition according to Example 1 is applied to this image.

 The image illuminated by the luminescent coating can be observed in the dark, through the thickness of the bottle.

 Example 5

 A glass vial is produced whose walls are honeycombed.

 The cells are printed by serigraphy using compositions according to Example 2.

Decorations are obtained on each of the overlapping faces and create a particularly attractive effect when the viewing angle changes. Example 6

 Three layers of lacquer are deposited successively on a glass container, respectively containing phosphorescent pigments of sizes 150 microns, 100 microns and 50 microns.

 A relatively smooth final finish with no raster effect is obtained.

Example 7

 A composition is prepared by mixing a maximum of 60% of phosphor and at least 40% of a mixture of ultraviolet-type high viscosity inks.

 The filler comprises 70% of 35 micron luminescent pigments of medium size and 30% of 25 micron luminescent pigments of medium size.

 The composition is applied by screen printing to a glass container, with a frame composed of a mesh of 32 threads per cm and a capillary film with a thickness ranging from 40 microns to 100 microns. Then, it is irradiated with a UV lamp which can thus create an overlayer and increase the luminescence.

 The baking is then carried out at 140 ° C. to trigger the complete polymerization of the coating.

 Of course, the invention is not limited to the examples which have just been described. It is possible, for example, to use pigments having different persistence periods to vary the optical effects observed over time.

 The expression "between" means included limits.

Claims

An article comprising a substrate at least partially covered by at least one layer of a luminescent coating having a thickness greater than 30 microns.  2. Article according to claim 1, the luminescent coating being phosphorescent.  3. Article according to one of the preceding claims, the luminescent coating having a thickness between 30 and 1500 microns, better 50 and 900 microns, more preferably 100 and 900 microns.  4. Article according to any one of the preceding claims, the coating comprising luminescent grains, especially phosphorescent, size between 15 and 200 microns, better between 30 and 180 microns.  5. Article according to any one of the preceding claims, the coating comprising a phosphor charge comprising a mixture of luminescent grains, in particular phosphorescent, having different sizes, preferably average mass sizes D 50 which differ from each other by more than 30%. taking as reference the grains of the smallest size.  6. Article according to any one of the preceding claims, the coating comprising a phosphor charge comprising a mixture of a first luminescent pigment, especially phosphorescent, of size between 30 and 70 microns, a second luminescent pigment, especially phosphorescent, of size between 70 and 110 microns, and a third luminescent pigment, especially phosphorescent, of size between 130 and 170 microns, each of the three pigments preferably representing between 20 and 40% by weight of the filler.  7. Article according to any one of claims 1 to 6, the coating comprising a phosphorescent charge comprising at least one phosphor-based pigment alkaline earth aluminate doped with one or more rare earths. 8. Article according to any one of claims 1 to 7, the coating comprising a phosphorescent charge comprising at least one phosphorescent pigment composite comprising a grain of a phosphorescent material, in particular an aluminate alkaline earth doped with one or more rare earths, at least partially covered by smaller grains of a metal oxide, in particular ferrous or non-ferrous.  9. Article according to claim 8, the size of the oxide (s) metal (s), including non-ferrous, being less than or equal to 1 micron.  10. Article according to one of claims 8 and 9, the mass proportion of oxide grains (s) metal (s) being less than or equal to 1% within the luminescent charge.  11. Article according to any one of the preceding claims, the coating comprising a transparent matrix.  12. Article according to any one of the preceding claims, the substrate being made of glass.  13. Article according to any one of claims 1 to 11, the substrate being metal, plastic or a material of plant or animal origin, including wood.  14. Luminescent lacquering composition, in particular for producing a coating of an article according to any one of claims 1 to 13, comprising in dry weight:  between 30 and 75% of a luminescent charge,  - Between 25 and 50% of a binder, preferably based on polyurethane. 15. Composition according to claim 14, comprising between 0.5 and 2% by dry weight of gelling agent.  16. Composition according to one of claims 14 and 15, the load being of particle size between 30 microns and 400 microns, better between 30 and 300 microns, more preferably between 30 and 200 microns.  17. Composition according to any one of claims 14 to 16, the phosphor charge comprising a mixture of at least two luminescent pigments, in particular phosphorescent, of different particle sizes, preferably differing from each other by at least 30%, taking as a reference the smallest particle size. 18. Composition according to any one of claims 14 to 17, the luminescent charge comprising a mixture of a first luminescent pigment, in particular phosphorescent pigment, of size between 30 and 70 microns, of a second luminescent pigment, especially phosphorescent, of size between 70 and 110 microns, and a third luminescent pigment, in particular a phosphorescent pigment, of size between 130 and 170 microns, each of the three pigments preferably representing between 20 and 40% by weight of the filler, the phosphor load preferably comprising at least one phosphorescent pigment based on alkaline earth aluminate aluminate doped with one or more rare earths, the phosphor feed preferably comprising at least one composite phosphorescent pigment comprising a grain of a phosphorescent material, in particular an alkaline earth aluminate doped with one or more rare earths, at least partially covered by smaller grains of a metal oxide, the size of the oxide (s) metal (s) being preferably less than or equal to 1 micron, the mass proportion of oxide grains (s) metal (s) being preferably less than or equal to 1% within the luminescent charge.  19. A method of lacquering a substrate, in particular glass, comprising sputtering onto the substrate of a composition as defined in any one of claims 14 to 18, so as to obtain after coating a deposit thickness greater than 30 microns, preferably a thickness between 100 and 1500 microns, better between 200 and 900 microns.  20. Luminescent enameling composition, in particular for the production of a coating of an article according to any one of claims 1 to 13, comprising a colorless transparent glass flux and a luminescent charge comprising at least one luminescent pigment, in particular phosphorescent, the glass flux being preferably constituted by glass microbeads, the particle size of the flux being preferably between 100 and 200 microns.  21. Composition according to claim 20, the proportion by dry weight of the phosphor load being between 35 and 55% relative to the total weight of the composition, more preferably between 40 and 50%, the proportion by dry weight of the flux being reference between 35 and 55% relative to the total weight of the composition, more preferably between 40 and 50%. 22. Composition according to one of claims 20 and 21, the phosphor load comprising a mixture of at least two luminescent pigments, especially phosphorescent pigments, of different particle sizes, preferably differing from each other by at least 30% by taking as a reference the the smallest particle size, the luminescent charge preferably comprising a mixture of a first luminescent pigment, in particular phosphorescent, of size between 30 and 70 microns, a second luminescent pigment, especially phosphorescent, size between 70 and 110 microns, and a third luminescent pigment, including phosphorescent, size between 130 and 170 microns , each of the three pigments preferably representing between 20 and 40% by weight of the filler, the phosphor load preferably comprising at least one phosphor-based pigment based on alkaline earth metal aluminate doped with one or more rare earths, the luminescent filler comprising preferably at least one composite phosphorescent pigment having a grain of a phosphorescent material, in particular an alkaline earth aluminate doped with one or more rare earths, at least partially covered by smaller grains of a non-ferrous metal oxide, having a decomposition temperature greater than or equal to 550 ° C, better at 600 ° C, the size of the oxide grains (s) metal the non-ferrous acid (s) being preferably less than or equal to 1 micron, the mass proportion of the oxide (s) metal (s) being preferably less than or equal to 1% within the luminescent charge.  23. A method of enameling a substrate, comprising applying the composition according to any one of claims 20 to 22 to the substrate and baking the composition at a temperature sufficient to cause melting of the flux, in particular a temperature greater than or equal to 550 ° C, better still greater than or equal to 600 ° C.  24. Composition intended for application by screen printing, in particular in order to achieve a luminescent coating of an article as defined in any one of claims 1 to 13, comprising a two-component resin, in particular an epoxy resin, and a filler. luminescent, in particular phosphorescent, in a mass proportion by dry weight greater than or equal to 50% relative to the total weight of the composition, better still between 50 and 75% by dry weight. 25. A composition according to claim 24, the phosphor charge comprising a mixture of at least two luminescent pigments, especially phosphorescent pigments, of different particle sizes, preferably differing from each other by at least 30%, taking as a reference the smallest particle size, the luminescent charge preferably comprising a mixture of a first luminescent pigment, in particular a phosphorescent pigment, ranging in size from 30 to 70 microns, a second luminescent pigment, in particular a phosphorescent pigment, of size between 70 and 110 microns, and a third pigment luminescent, in particular phosphorescent, of size between 130 and 170 microns, each of the three pigments preferably representing between 20 and 40% by weight of the filler, the phosphor load preferably comprising at least one phosphor-based pigment based on aluminum aluminate. alkaline earth doped with one or more rare earths, the phosphor feed preferably comprising at least one composite phosphorescent pigment comprising a grain of a phosphorescent material, in particular an alkaline earth aluminate doped with one or more rare earths, at least partially covered by smaller grains of a ferrous or non-ferrous metal oxide, having when preferably non-ferrous a decomposition temperature greater than or equal to 550 ° C, more preferably at 600 ° C, the size of the oxide (s) metal grains (s) ) is preferably less than or equal to 1 micron, the mass proportion of the grains of metal oxide (s) being preferably lower than 1% or less in the luminescent charge.  26. A method of application by screen printing an enameling composition according to any one of claims 20 to 22 or a screen printing composition according to one of claims 24 and 25, the screen printing being performed with a screen having from 40 to 80 threads / cm and with a capillary film 100 to 900 microns thick. 27. Luminescent composition, in particular phosphorescent composition, in particular for producing the luminescent coating of an article as defined in any one of Claims 1 to 13, comprising a phosphorescent filler comprising a mixture of at least two luminescent pigments, in particular phosphorescent pigments. of different particle sizes, preferably differing from each other by at least 30%, taking as a reference the smallest particle size, the phosphor load preferably comprising a mixture of a first luminescent pigment, in particular a phosphorescent pigment, preferably of a size between 30 and 70 microns, a second luminescent pigment, especially phosphorescent, preferably of size between 70 and 110 microns, and a third luminescent pigment, especially phosphorescent, preferably of size between 130 and 170 microns, each of three pigments preferably representing between 20 and 40% by weight of the charge, the charge light-emitting element preferably comprising at least one phosphor-based pigment based on alkaline earth metal aluminate doped with one or more rare earths, the phosphor charge preferably comprising at least one phosphorescent composite pigment comprising a grain of a phosphorescent material, in particular an aluminate d alkaline earth metal doped with one or more rare earths, covered at least partially by smaller grains of a ferrous or non-ferrous metal oxide, having when preferably non-ferrous a decomposition temperature greater than or equal to 550 ° C, more preferably at 600 ° C, the size of the oxide grains (s) metal (s) being preferably less than or equal to 1 micron, the mass proportion of the oxide grains (s) metal (s) being preferably less than or equal to 1% within the luminescent charge.  28. The composition of claim 27, comprising a flux or a binder capable of constituting after baking or drying a transparent matrix.  29. Article, in particular containing, comprising a body made of a transparent material, in particular glass, having two opposite faces, coated with respective images each formed with a phosphorescent coating, in particular with the aid of a composition according to one of the claims 20 to 22 or 24 or 25, the images being applied in a manner marked with respect to each other.  30. Article, in particular a container, comprising a body made of a transparent material, in particular glass, having a face on which a non-luminescent image is printed, and comprising a luminescent coating at least partially covering the image, the latter being observable for a period of time. opposite side of the article through said body, the luminescent coating being in particular made using a composition according to any one of claims 14 to 18, 20 to 22 or 24 or 25.  31. A method for producing a luminescent coating, in particular a phosphorescent coating, on a substrate, in particular for producing an article as defined in any one of claims 1 to 13, in which at least a first layer and then a second layer are deposited successively. the substrate, the first layer comprising a luminescent charge comprising a luminescent pigment of a first average size, and the second layer comprising a luminescent pigment of a second average size less than the first. 32. Process for producing a luminescent coating, in particular a phosphorescent coating, on a substrate, in particular for producing an article as defined in any one of Claims 1 to 13, in which at least one layer of a luminescent coating is deposited, and wherein ultraviolet radiation is used to polymerize the substrate coated with said at least one layer. 33. Method according to the preceding claim, wherein the ultraviolet wavelengths chosen to polymerize the substrate are between 200 and 400 nanometers.