Method for enhancing a hollow glass body and related article

Abstract

The present invention relates to a method for finishing a hollow body having a glass wall and at least one opening, said method comprising at least one annealing sealing step, under a flow of gas delivered through said at least one opening by at least one supply tube, of at least one layer of at least one coating on at least one portion of the inner glass face of the hollow body. [Fig. 1]

Description

Title of the invention: Method for embellishing a hollow glass body and related article technical field

[0001] The present invention relates to the field of manufacturing objects and containers with a glass wall. It also relates to the field of finishing glass surfaces. Such objects and containers can be designed for functional and / or decorative purposes.

[0002] State of the art

[0003] The present invention relates to a method for enhancing a hollow glass body, a hollow body obtained by such a method, an article comprising at least one such hollow body and an installation enabling the implementation of such a method.

[0004] Processes for decorating the external and / or internal surfaces of glass objects such as perfume bottles, light bulbs and lamps or tubing have been known for a long time.

[0005] Most often, the manufacturing and the treatment or coating of the object's surface are carried out simultaneously, for example by choosing the colors, layers, and physicochemical characteristics of the glass(es) being shaped. Manufacturing and processing using the glassmaking technique known as overlay or multi-layered glass is one example, as is slumping, also called "melting" in English.

[0006] Alternatively, the treatment or coating is classically carried out at the interface between two layers or on the outer surface of the object, using various materials, by methods such as the technique of decorative glass or intercalary painting, coating for example for paints or polymers, or even by chemical modification for example by molecular grafting.

[0007] These methods present high risks of breakage, degradation, alteration or disintegration of the coating deposited during the aging of the object, for example by mechanical or chemical erosion or by thermal deterioration.

[0008] Also, while such methods are easy to use on objects with large, relatively flat surfaces and / or large, easily accessible internal volumes, they prove impractical when the item to be handled has small openings and / or a closed or almost closed internal volume. Such a situation frequently arises. One thinks, for example, of swan-neck flasks or vases, or even complex objects such as Galileo's thermometers.

[0009] Inhomogeneous deposits of materials can occur, for example by the creation of excess thickness or, on the contrary, the absence of deposit in areas that are difficult to access.

[0010] For their part, the traditional techniques used in stained glass form an even more specific category of glasswork and decoration. The use of delicate materials such as lusters or gold proves complex for the craftsman and very difficult to industrialize, because their behavior and the repeatability in obtaining their effect depend heavily on their chemical composition, the material environment used, and the firing curves applied.

[0011] Metallic lusters have been worked in Europe since the 14th century and their production requires two firings, one oxidizing at around 900°C, the other reducing at around 650°C.

[0012] It is known that reducing firing can occur during part of the work cycle of an object by a metallic luster. This is particularly the case when the metallic luster contains petroleum derivatives, naphthalene, or rubber. During the incomplete combustion of the carbon in these chemical compounds, carbon monoxide, carbon dioxide, and / or hydrogen can be formed, while combustible compounds are incompletely oxidized. The impact of these uncontrolled variations on the final result of the object is considerable and quite unpredictable. Conversely, reducing conditions are sometimes necessary to obtain the desired, possibly metallic, effect.

[0013] Thus, as each chandelier, gold, enamel or precious or non-precious metallic compound is associated with its individualized and difficult-to-control working methods and conditions, it is easy to understand that these traditional stained glass techniques are used for very small series or even exclusively for unique pieces, with a long and often random development, low yield and high cost.

[0014] Lustre means a solution comprising at least one metallic compound such as a metallic salt or a metallic resinate.

[0015] Finally, current techniques for working and decorating glass require, on the one hand, high temperatures: grisaille is fired at 600°C, silver stain is fired at 580°C, enamels between 550 and 580°C, precious metal lusters such as gold are fired from 580°C and usually between 700°C and 850°C, and on the other hand, long firing times. Summary of the invention

[0016] One of the aims of the present invention is to solve, in particular, the aforementioned problems.

[0017] Another object of the invention is to propose a process which ensures uniform conditions and can be used for a wide range of coatings.

[0018] Another object of the invention is to propose a finishing process under controlled, reducing, neutral or oxidizing conditions suitable for a wide range of coatings, including coatings adapted or usually requiring reducing conditions.

[0019] Another object of the invention is to propose a rapid process, which lowers the temperatures required for the desired finishing and is therefore less energy-intensive.

[0020] Another object of the invention is to propose a process presenting conditions close to those of chemical tempering of glass and which allows obtaining similar qualities such as improved mechanical resistance.

[0021] Thus, the invention aims in particular to propose a method for enhancing a hollow body delimiting an interior volume, said hollow body comprising at least one glass wall and comprising at least one opening, said at least one wall having an internal face located opposite said interior volume, said at least one opening being at least temporary.

[0022] The finishing process according to the invention is particularly well suited to the case of a hollow body whose internal volume is difficult to access for whatever reason, for example: body with small dimensions such as an earring, presence of a single opening, presence of small openings, hollow body which must be completely closed at the end of the procedure for its use such as a globe.

[0023] The hollow body according to the invention delimits, by virtue of the existence of at least one material wall that constitutes it, an internal volume, at least a part of which may be difficult to access. In other words, the internal volume according to the invention has at least one quasi-closed sub-volume.

[0024] By way of illustration, one might consider objects exhibiting, for example: folds, tubes that are very long compared to their cross-section, spiral tubes, or areas of constriction. The said material wall has an inner face located opposite the said inner volume and is made up of all the walls constituting the hollow body.

[0025] The hollow body according to the invention has at least one glass wall. It may have at least one other wall made of a different material such as a metal or a polymer. A person skilled in the art knows how to choose suitable materials to serve as walls in such a process. Such a choice is based, for example, on the compatibility between two types of glass, which depends on their coefficient of expansion, or on the compatibility of the glass with other materials. It is particularly known that glass has a good compatibility with precious metals such as for example: gold, silver, platinum, copper.

[0026] Preferably the hollow body is entirely made up of a glass wall, which has an internal face located opposite said internal volume, and an external face.

[0027] Most preferably, said at least one glass wall is of the borosilicate type.

[0028] The finishing process according to the invention may include a step of shaping said glass wall by blowing the glass. However, the proposed process can be applied to any glass wall regardless of its manufacturing process, whether industrial or artisanal.

[0029] The hollow body according to the invention has at least one opening. This at least one opening is formed in the material wall of the hollow body or is constituted by its edge. Preferably, this at least one opening is formed in the glass wall or is constituted by its edge.

[0030] Advantageously, said at least one opening is at least temporary. In certain variants of the finishing process, it may include a step of closing at least one opening, for example by adding material or by working the existing material.

[0031] The finishing process according to the invention comprises at least one sealing step by annealing, under a flow of gas delivered through said at least one opening by at least one supply tube, of at least one layer of at least one coating at the level of at least one portion of said inner face.

[0032] The annealing sealing step allows the fixing of at least one layer of at least one coating at the level of at least one portion of said internal face facing the internal volume of the hollow body.

[0033] Thus, the annealing sealing step according to the invention makes it possible to seal, as required, any combination among: - one or more layers of the same coating; - one or more layers of different coatings; - at the level of a portion of said inner face; - at the level of the entirety of said inner face.

[0034] The term "at the level of" means that the coating can, alone or in combination: - be in direct contact with said inner surface; - be supported by said inner face by means of at least one other identical or different coating layer; - be included in said inner face.

[0035] The term "included" means that the coating is encompassed by said inner face and / or has undergone a chemical and / or structural modification causing it to be bonded or confused with said inner face.

[0036] The sealing step by annealing is carried out under a flow of gas delivered through said at least one opening by at least one supply tube.

[0037] Preferably at least one supply tube is made of glass.

[0038] In order to deliver the gas flow through said at least one opening by at least one supply pipe, several installation variants can be envisaged.

[0039] An opening intended to be supplied by the gas flow is called the inlet opening of said flow. An opening not intended to be supplied by the gas flow is called the outlet opening of said flow.

[0040] Depending on the variations, needs, and dimensional constraints, a person skilled in the art can adapt the piping system. For example, in the case of widely spaced openings, several supply pipes can be used, while in the case of closely spaced openings or a single opening, a single main supply pipe, possibly branched at its end, can be implemented. Similarly, a single pipe can supply several openings simultaneously.

[0041] A person skilled in the art knows how to choose the most suitable arrangement according to the conformation of the object and the coating to be sealed.

[0042] By way of non-limitation, variants of the invention may thus have at least one of the following characteristics: - at least one supply pipe feeds an inlet opening; - when several openings are provided, at least one supply pipe is provided and at least one opening is an outlet opening for the gas flow.

[0043] Advantageously the outlet surface of the supply tube has a complementarity with the surface of the opening which it feeds.

[0044] Advantageously the outlet surface of the supply tube and the surface of the opening which it feeds are arranged opposite each other.

[0045] Preferably, the hollow body has an inlet opening fed by a tube and an outlet opening.

[0046] Quite preferably, the hollow body has at least two openings.

[0047] Most preferably, at least one inlet opening and / or at least one outlet opening are located at the level of the glass wall.

[0048] Most preferably, at least one inlet opening and / or at least one outlet opening allow, by their arrangement and dimensions, a laminar and / or turbulent diffusion of the gas flow in the internal volume at least at the level of said coating, so that the flow takes place along a trajectory parallel or almost parallel to the glass wall.

[0049] Advantageously, the gas flow delivered through said at least one opening has a flow rate ensuring its laminar and / or turbulent diffusion within the internal volume, at least at the level of said lining. Preferably, the flow rate of the gas flow delivered through said at least one opening is between 50 liters per hour and 400 liters per hour. Most preferably, the flow rate of the gas flow delivered through each opening is between 100 liters per hour and 300 liters per hour.

[0050] Advantageously, the gas is chosen from among: air, oxygen, ozone, nitrogen, carbonaceous gases such as carbon monoxide or carbon dioxide, noble gases, hydrogen, and stable mixtures thereof. Preferably, the gas chosen is air when the conditions to be maintained are oxidizing conditions. Preferably, the gas chosen is carbon monoxide when the conditions to be maintained are reducing conditions. Indeed, under the effect of carbon monoxide, it is notably possible to control the modification of the metal ions of a metallic luster coating by lowering their oxidation state.

[0051] Such a gas flow allows for the maintenance of controlled conditions within the internal volume. Indeed, by its configuration and the confinement it generates, the internal volume of the hollow body according to the invention constitutes an environment whose thermal and / or physicochemical evolution conditions can vary considerably and do not necessarily correspond to the conditions of the overall volume of the enclosure in which the process takes place.

[0052] The gas flow thus makes it possible, among other things, to control the local conditions within the internal volume, in particular the local variations of temperature and / or physico-chemical atmosphere, for example by avoiding a temperature rise too rapid and / or by removing by-products of chemical reactions such as gases or vaporized particles in suspension.

[0053] Advantageously, the finishing process according to the invention comprises at least one step of depositing at least one layer of at least one coating. The deposition can be carried out by any conceivable technique.

[0054] By way of non-limiting examples, depending on the nature of the coating: - liquid to slightly pasty coating: by spraying, by pouring, by brush; - very pasty or solid coating: with a brush, spatula, or tweezers;

[0055] Advantageously, the finishing process according to the invention comprises a texturing step of at least a portion of said inner face and / or at least a portion of said outer face of said glass wall, for example by mechanical action or chemical treatment. This step involves acting on at least one of the inner and / or outer faces of the glass wall in order to texture it, that is to say, to create roughness such as grooves and / or protrusions. To this end A skilled craftsman knows how to apply the appropriate techniques, whether hot or cold. For example, hot glass can be textured using tools such as pliers, scissors, palette knives, or molds. Cold glass can be textured by mechanically scratching or sandblasting its surface, for instance, using corundum, by bush hammering, or by applying a chemical treatment such as hydrofluoric acid etching.

[0056] The texturing step may be preceded and / or followed by a relaxation step.

[0057] In addition to or as an alternative to the texturing of at least a portion of said inner face and / or at least a portion of said outer face of said glass wall itself, texturing may be provided by the use of an external texturing agent.

[0058] Advantageously according to the invention at least one coating is chosen from: texturizing agent, coating composition.

[0059] A texturizing agent is understood to be a material capable of creating, by its presence—that is, by itself or by reaction with its environment—irregularities or roughness at the location of its deposit and capable of being sealed by the process according to the invention. Preferably, the texturizing agent is in solid form, such as a powder. Advantageously, said texturizing agent is selected from: tartar powder, ash, glass particles, metallic flakes. Most preferably, the texturizing agent is selected from: tartar powder, vegetable ash, bone ash, glass particles, metallic particles such as metal oxides.

[0060] The term coating composition means a composition in a paste or liquid state suitable for sealing by the process according to the invention.

[0061] Advantageously, said coating composition comprises at least one metallic compound and at least one solvent. Advantageously the coating composition is a ready-to-use composition such as for example: metallic or non-metallic luster, metallic composition, enamel.

[0062] Alternatively, the coating composition is custom-made. Preferably, in the variants where the coating composition is custom-made, it comprises at least one metallic compound and at least one solvent.

[0063] A metallic compound is understood to be a compound selected from: metallic particles, metallic salts, metallic oxides, metallic resinates, metallic complexes. Preferably, at least one metallic compound is a metallic compound of a precious metal such as, for example, gold, silver, or platinum.

[0064] The term solvent means any compound capable of dissolving at least one metallic compound of said coating composition. The at least one solvent is capable of giving the coating composition its homogeneity in the liquid state or pasty. At least one solvent according to the invention allows adjustment of the viscosity of the coating composition and / or the contact angle relative to the substrate surface. Advantageously, at least one solvent is chosen from: oils, essential oils, synthetic and / or natural resins, organic solvents.

[0065] Preferably, when the solvent is a resin, it is chosen from: turpentine, rosin.

[0066] Preferably, when the solvent is an organic solvent, it is chosen from: hydrocarbons, alcohols, glycol ethers, ketones.

[0067] Most preferably, when the solvent is a hydrocarbon, it is chosen from: halogenated aliphatic hydrocarbons such as dichloromethane, aromatic hydrocarbons such as, for example: terpene hydrocarbons, light naphtha solvent, phenols, toluene.

[0068] Even more preferably the coating composition further comprises at least one compound from: flux, cement, frit, binder, catalyst.

[0069] A flux is defined as a compound capable of lowering, by eutectic means, the melting point of the system formed by the silica in the glass and the coating composition that includes said flux. Advantageously, the flux-type compound is selected alone or in a mixture from among: alkali flux, alkaline earth flux. By way of example: lithium oxide, sodium oxide, potassium oxide, calcium oxide, magnesium oxide, strontium oxide, barium oxide, zinc oxide, lead oxide, boron oxide. Some fluxes, such as calcium oxide, also act as stabilizers for the mixture formed by the silica in the glass and the coating composition that includes said flux.

[0070] The choice of at least one flux also influences the decorative color obtained and vice versa. Indeed, the color obtained depends on the compounds selected, whether these are used in the coating composition as pigments, fluxes or otherwise.

[0071] By way of example, the simplest colors may include: - red: iron oxide, - green: copper oxides, chromium oxide, - blue: cobalt oxide, - brown: manganese oxide, - pink: tin and chromium oxides, - yellow: vanadium and antimony oxides, - white: tin oxides, zirconium oxide, - black: iron oxide.

[0072] Cement refers to any material that promotes ion exchange between glass and metallic compounds such as metal salts during firing. Preferably, for example: ochre, calcined clay.

[0073] The term frit means any forming oxide suitable for promoting vitrification, such as silica or borax.

[0074] A binder is defined as any substance capable of giving the coating composition its homogeneity in the liquid or paste state. The binder according to the invention allows the viscosity of the coating composition and / or the contact angle relative to the substrate surface to be adjusted. Preferably, at least one binder is chosen from: gum arabic, sugars.

[0075] At least one flux-type compound and / or cement and / or frit are suitable for enabling the vitrification of the coating during the sealing step.

[0076] Certain compounds in the coating composition may exhibit cumulative properties. For example, bone ash is a texturizing agent derived from bone calcination and, due to its composition, provides, among other things, calcium oxide, which is a flux, and phosphorus, which is a glaze-forming agent. Similarly, kaolin clay, containing alumina and silica, stabilizes the coating, increases viscosity, and promotes vitrification.

[0077] Advantageously, the process according to the invention includes a drying step of said coating composition, preferably at ambient temperature. Alternatively, the drying can be carried out in an oven at a temperature of 70°C or lower. Such a drying step makes it possible, particularly for certain coatings in the form of a coating composition, to obtain better stability and / or homogeneity prior to sealing. Such a drying step also makes it possible to reduce or even eliminate any trace of solvent, in particular water, whether intrinsic or not, in the coating.For example, in the case of a composition containing a metallic compound in the form of micro- or nanoparticles, moderate drying in terms of temperature and / or speed helps to limit the "coffee ring" effect, in which particles accumulate more abundantly at the edge of the droplet or liquid film than in its center, thus creating an uneven appearance. Those skilled in the art know how to determine, based on the chosen coating, whether such a drying step is appropriate and what its parameters should be.

[0078] Advantageously, said coating composition has, after deposition, a contact angle relative to the substrate surface of less than 30°, preferably less than 15°. The control of the contact angle parameter can be carried out by any technique known to those skilled in the art, such as the sessile drop method.

[0079] In order to achieve the aforementioned objectives of the invention, the annealing sealing step is carried out: - according to a processing curve, also called a cooking curve, with a specific shape and a minimized maximum temperature, adapted to a wide range of coatings that usually require individualized processes and curves and much higher temperatures, - under gas flow, allowing the maintenance of a controlled atmosphere in the interior volume, suitable for a wide range of coatings and which would usually require individualized processes.

[0080] Thus, at least one sealing step by annealing of the finishing process is advantageously carried out in a temperature range between a minimum temperature TMIN and a maximum temperature TMAX and includes: - the initialization of said sealing step at an inlet temperature TE, - at least one sub-step of linear temperature ramping between an initial ramp temperature TIR1, TIR2 and a final ramp temperature TFR1, TFR2, - at least one sub-step of holding at a plateau temperature TPI, TP2.

[0081] Advantageously the minimum temperature TMIN of the sealing step is between ambient temperature and 100°C.

[0082] Advantageously, the maximum temperature TMAX of the sealing step is between 500°C and 650°C, preferably 580°C. This maximum temperature is therefore lower than the usual practices implemented.

[0083] The inlet temperature TE corresponds to the introduction, such as the inking, of the hollow body into the enclosure of the installation allowing the execution of the process according to the invention.

[0084] Advantageously the inlet temperature TE is greater than or equal to the minimum temperature TMIN and less than or equal to 200°C, preferably 150°C.

[0085] Preferably, during the sealing step (E2) by annealing, a first linear temperature ramp substep takes place between an initial ramp temperature corresponding to the inlet temperature TE and a final ramp temperature between 350°C and 450°C, preferably 400°C.

[0086] Preferably, during the sealing step (E2) by annealing, a second linear temperature ramp substep takes place between an initial ramp temperature between 350°C and 450°C, preferably 400°C and a final ramp temperature TFR2 less than or equal to the maximum temperature TMAX.

[0087] Preferably, each sub-step of linear temperature rise takes place over a duration DL of between 5 minutes and 1 hour, preferably 20 minutes.

[0088] Preferably, during the sealing step (E2) by annealing, a first substep of holding the temperature is carried out at a plateau temperature between 350°C and 450°C, preferably 400°C. During this first substep of holding the temperature, when at least one coating is a composition During the coating process, any organic components present are consumed and / or the reaction revealing the metallic appearance can occur. This first sub-step of holding the material at a plateau temperature between 350°C and 450°C, preferably 400°C, achieves a chemical hardening that confers, at least locally, enhanced mechanical properties to the treated hollow body.

[0089] Preferably, during the sealing step (E2) by annealing, a second substep of temperature holding is carried out at a plateau temperature between 450°C and the maximum temperature TMAX. This second substep, when at least one coating is a coating composition, ensures the durability of the coating by its hardening and / or its embedding in the wall.

[0090] Preferably each sub-step of temperature maintenance is carried out for a duration DP of between 5 minutes and 1 hour, preferably 20 minutes.

[0091] Preferably, the sealing step (E2) by annealing further comprises at least one linear cooling substep carried out between: - a starting temperature corresponding to the final temperature of the preceding sub-step among the linear temperature ramp-up and temperature maintenance steps, and - an arrival temperature corresponding to the initial temperature of the sub-step that follows it or to an outlet temperature TS, lower than the starting temperature.

[0092] Most preferably, the sealing step (E2) by annealing comprises a single linear cooling substep, as the last substep of the sealing step by annealing, i.e. after all the linear heating and holding substeps, this single linear cooling substep taking place between the temperature TF reached at the end of the last step among the linear heating and holding steps and an outlet temperature TS which is lower than it.

[0093] Preferably, the DRL duration of at least one linear cooling substep is between 15 minutes and 1 hour, most preferably 40 minutes.

[0094] The outlet temperature TS corresponds to the extraction, such as the unburdening, of the hollow body in the enclosure of the installation allowing the execution of the process according to the invention.

[0095] Preferably the outlet temperature TS is greater than or equal to the minimum temperature TMIN and less than or equal to 100°C, preferably 70°C.

[0096] Advantageously the duration of the sealing step is between 35 minutes and 5 hours.

[0097] Advantageously, the finishing process includes at least one relaxation step including: - at least one linear temperature ramp sub-step between an initial ramp temperature greater than or equal to ambient temperature and less than or equal to 200°C, preferably 150°C, and a final ramp temperature between 400°C and 650°C, - at least one sub-step of maintaining temperature at a plateau temperature between 400°C and 650°C.

[0098] Advantageously the relaxation stage takes place over a period of between 10 minutes and 2 hours, preferably between 15 minutes and 1 hour.

[0099] Preferably the relaxation step includes a temperature rise sub-step which takes place over a period of between 5 minutes and 1 hour, preferably of a duration of 20 minutes and includes a temperature maintenance sub-step which takes place over a period of between 5 minutes and 1 hour, preferably of a duration of 20 minutes.

[0100] During the process, one or more relaxation steps may be provided, in order to allow the relief of tensions in the glass and to avoid any damage to the hollow body.

[0101] Most preferably, a relaxation step is coincident with the sealing step and / or constitutes a sub-step thereof.

[0102] The invention also relates to a hollow body obtained by the finishing process described above, delimiting an internal volume, said hollow body comprising at least one glass wall and comprising at least one opening, said at least one wall having an internal face located opposite said internal volume, and having at least one layer of at least one coating sealed under gas flow at the level of at least a portion of said internal face.

[0103] Examples of hollow bodies according to the invention include: beads, globes, pendants, rings, bottles, vases.

[0104] The invention also relates to an article comprising at least one hollow body according to the invention, such as: bracelet, necklace, earrings, beads, functional object, decorative object.

[0105] The invention also relates to an installation for manufacturing a hollow body as described above, designed and configured to implement the finishing process described above and comprising: - an enclosure, such as an oven, suitable for housing and thermally treating said hollow body, - at least one gas supply pipe inside said enclosure, capable of delivering the gas flow through said at least one opening of said hollow body, - a gas flow supply system, such as a pump possibly associated with a means of storing said gas, capable of cooperating with at least one gas supply pipe.

[0106] Preferably the oven is an electric oven.

[0107] Quite preferably at least one supply tube is made of glass.

[0108] Advantageously the installation according to the invention includes at least one support suitable for holding the hollow body and / or at least one supply tube.

[0109] Preferably at least one support allows the hollow body and / or at least one supply tube to be positioned so that the gas flow is laminar and / or turbulent.

[0110] Preferably at least one support allows the hollow body and / or at least one supply tube to be positioned so that the gas flow through at least one opening is substantially parallel to the inner face.

[0111] Most preferably, at least one support allows the hollow body and / or at least one supply tube to be positioned so that the gas flow through at least one opening is substantially through, that is to say oriented along an imaginary axis passing through two openings.

[0112] Preferably the support is made of fiber-ceramic. Figures

[0113] The features and advantages of the invention will become apparent from the following description, given solely by way of example and not limitation, with reference to the following attached figures:

[0114] [Fig.1]

[0115] Fig. 1 schematically represents the steps of the process according to a preferred variant of the invention;

[0116] [Fig.2] Figure [Fig. 2] schematically represents an example of a hollow body according to the invention;

[0117] [Fig.3] Figure [Fig. 3] schematically represents the general shape of the cooking curve according to a preferred variant of the invention;

[0118] [Fig.4]

[0119] Fig. 2 schematically represents an example of an installation according to the invention. Detailed description

[0120] Figures 1 to 4 illustrate an example of the arrangement of process steps, the cooking curve, a hollow body and the associated installation, according to a preferred embodiment of the invention.

[0121] As a particular embodiment shown in [Fig.2] a hollow body 1, intended for a pendant-type article, is considered, having a texture by a texturing agent 3 in the form of ash and a decoration by a metallic luster 3, the texturing agent 3 and the luster 4 having been sealed by the process according to the invention, using the installation according to [Fig.4].

[0122] Figure 2 illustrates a hollow body 1 delimiting an internal volume 2. In this example, said hollow body 1 consists exclusively of a glass wall 10 and has two openings 30, 31. Said glass wall 10 has an internal face (20) located opposite said internal volume 2. The internal face 20 has been treated by the finishing process so as to locally receive a texturing agent 3 in the form of ash and a metallic luster 4. The layers consisting of the texturing agent 3 and the luster 4 overlap at at least one overlap zone 5 and are sealed by the process.

[0123] Figure 1 illustrates the general finishing process according to the invention, implementing the following various steps and parameters: - optionally, a step 01 of the fabrication of at least one glass wall 10 by blowing the glass; - optionally, at least one relaxation step 02 including: - at least one linear temperature rise substep 022, - at least one temperature maintenance substep 023; - optionally, a texturing step 03 of at least a portion of said inner face 20 and / or of at least a portion of said outer face of said glass wall 10; - optionally, a step to improve the condition of the surface to be finished, for example by cleaning, by degreasing with alcohol, or even by smoothing and / or removing irregularities by mechanical action; - a deposition step El of at least one layer of at least one coating 3, 4; - optionally, a drying step 04 of the coating when it is a coating composition 4; - at least one sealing step E2 by annealing, under a flow of gas delivered through said at least one opening 30, 31 by at least one supply tube 60, of at least one layer of at least one coating 3,4 at the level of at least a portion of said internal face 20.

[0124] Advantageously, the sealing step E2 is carried out within a temperature range between a minimum temperature TMIN and a maximum temperature TMAX, for a duration DT and comprises: - the initialization E21 of said sealing step E2 at an inlet temperature TE between the minimum temperature TMIN and the maximum temperature TMAX; - at least one linear temperature ramp substep E22 between an initial ramp temperature TIR1, TIR2 and a final ramp temperature TFR1, TFR2, for a duration DL1, DL2; - at least one substep of maintaining temperature E23 at a plateau temperature TPI, TP2, for a duration DPI, DP2; - optionally at least one linear cooling substage 024; - optionally, a closing step 05 of at least one opening.

[0125] Fig. 3 illustrates a preferred variant of the curing curve for the sealing step, said curve having an initialization step E21 at temperature TE, TIR1 two temperature ramp-up substeps E22 and two temperature holding substeps E23, a temperature ramp-up substep E22 being followed by a temperature holding substep E23, and finally a linear cooling substep 024.

[0126] The embodiment shown in [Fig.2] relates to a hollow body 1 produced according to the process provided for by the invention, by implementing the following steps: - a manufacturing step 01 of the hollow body consisting of a glass wall 10 by blowing the glass; - a relaxation step 02 comprising a linear temperature rise substep 022 and a temperature maintenance substep 023; - a brush-on application step El of the desired coatings 3, 4 to be sealed, namely: a layer of ash as a texturizing agent 3 at the level of a portion of said internal face, and a layer of metallic luster 4 at the level of at least another portion of said internal face, with an overlap of one layer on the other at the level of at least one overlapping area 5; - a drying step 04 in open air and at ambient temperature; - a sealing step E2 by annealing, under airflow delivered through two openings 30, 31 by a supply tube 60, coatings 3, 4 in the form of ash and a metallic luster composition at the level of the selected portions of said internal face 20, according to the firing curve illustrated in [Fig.3].

[0127] The cooking curve includes sequentially in the example presented: - an initialization at an inlet temperature TE which corresponds to the loading into the chamber 60; - a first sub-step of temperature rise between an initial ramp temperature TIR1 corresponding to the inlet temperature TE and a final ramp temperature TFR1; - a first sub-step of maintaining temperature at a plateau temperature TPI corresponding to the final ramp temperature TFR1; - a second sub-step of temperature rise between an initial ramp temperature TIR2 corresponding to the plateau temperature TPI and a final ramp temperature TFR2; - a second sub-step of maintaining temperature at a plateau temperature TP2 corresponding to the final ramp temperature TFR2; - a linear cooling sub-step between the TF temperature reached at the end of the last step among the linear temperature rise and temperature maintenance steps corresponding in this example to the plateau temperature TP2 and an output temperature TS.

[0128] Figure 4 shows an example of an installation for manufacturing a hollow body 1 according to the process described above. The installation includes, for example, the following for working the hollow body 1 illustrated in Figure 2: - a 50 cm enclosure of the electric oven type; - an air supply tube 60 inside said enclosure 50, made of glass; - a pump 70 cooperating with the gas supply tubing 60, possibly stored in a suitable enclosure 71, preferably air; - a support 80 to hold the hollow body 1 and the supply tubing 60, made of fibro-ceramic.

[0129] It is easily understood that this detailed description relates to a particular example of the realization and implementation of the present invention, but that in no way does this description have any limiting character to the object of the invention; on the contrary, its objective is to remove any possible imprecision or misinterpretation of the following claims.

[0130] Thus, it will be understood that the examples of materials proposed, the shape of the hollow body illustrated or even the order of the steps presented can vary considerably depending on the creation intended.

[0131] Similarly, the reference signs placed in parentheses in the following claims are in no way intended to be limiting; these signs are solely intended to improve the intelligibility and understanding of the following claims and the scope of the protection sought.

Claims

Demands

1. A method for enhancing a hollow body (1) delimiting an internal volume (2), said hollow body (1) having at least one glass wall (10) and at least one opening (30, 31), said at least one wall (10) having an internal face (20) located opposite said internal volume (2) characterized in that it comprises: - at least one deposition step (E1) of at least one layer of at least one coating (3, 4); - at least one sealing step (E2) by annealing, under a flow of gas (F) delivered through said at least one opening (30, 31) by at least one supply tube (60), of at least one layer of at least one coating (3, 4) at the level of at least a portion of said internal face (20).

2. A method for enhancing a hollow body (1) according to the preceding claim, which includes a step of preparing said glass wall (10) by blowing the glass.

3. A method for enhancing a hollow body (1) according to any one of the preceding claims, wherein said glass wall (10) has an external face, and which comprises a texturing step (03) of at least a portion of said internal face (20) and / or at least a portion of said external face of said glass wall (10), for example by mechanical action or chemical treatment.

4. A method for enhancing a hollow body (1) according to any one of the preceding claims, wherein at least one coating is selected from: texturizing agent (3), coating composition (4).

5. A method for enhancing a hollow body (1) according to the preceding claim, which includes a drying step (04) of said coating composition (4), preferably at room temperature.

6. A method for enhancing a hollow body (1) according to any one of claims 4 or 5, said coating composition (4) comprises at least one metallic compound and at least one solvent.

7. A method for enhancing a hollow body (1) according to any one of claims 4 to 6, wherein said texturing agent (3) is selected from: tartar powder, ash, glass particles, metallic flakes.

8. A method for enhancing a hollow body (1) according to any one of the preceding claims, wherein the glass of said glass wall (10) is of the borosilicate type.

9. A method for enhancing a hollow body (1) according to any one of the preceding claims, wherein the sealing step (E2) by annealing is carried out in a temperature range between a minimum temperature TMIN and a maximum temperature TMAX and comprises: - the initialization (E21) of said sealing step (E2) at an inlet temperature TE; - at least one linear temperature ramp substep (E22) between an initial ramp temperature TIR1, TIR2 and a final ramp temperature TFR1, TFR2; - at least one temperature holding substep (E23) at a plateau temperature TPI, TP2.

10. A method for enhancing a hollow body (1) according to any one of the preceding claims, wherein the duration of the sealing step (E2) is between 35 minutes and 5 hours.

11. A method for enhancing a hollow body (1) according to any one of claims 9 or 10, wherein the minimum temperature TMIN of the sealing step (E2) is between ambient temperature and 100°C and wherein a maximum temperature TMAX of the sealing step (E2) is between 500°C and 650°C, preferably 580°C.

12. A method for enhancing a hollow body (1) according to any one of claims 9 to 11, wherein the inlet temperature TE is greater than or equal to the minimum temperature TMIN and less than or equal to 200°C, preferably 150°C.

13. A method for finishing a hollow body (1) according to any one of claims 9 to 12, wherein: - a first linear heating substep (E22) is carried out between an initial ramp temperature TIR1 corresponding to the inlet temperature TE and a final ramp temperature TFR1 of between 350°C and 450°C, preferably 400°C; - a second linear heating substep (E22) is carried out between an initial ramp temperature TIR2 of between 350°C and 450°C, preferably 400°C and a temperature final ramp TFR2 less than or equal to the maximum temperature TMAX; and in which each sub-step of linear temperature rise (E22) takes place for a duration DL (DL1, DL2) of between 5 minutes and 1 hour, preferably of 20 minutes.

14. A method for enhancing a hollow body (1) according to any one of claims 9 to 13, wherein a first substep of holding temperature (E23) is carried out at a plateau temperature between 350°C and 450°C, preferably 400°C, a second substep of holding temperature (E23) is carried out at a plateau temperature between 450°C and the maximum temperature TMAX, and wherein each substep of holding temperature (E23) is carried out for a duration DP (DPI, DP2) of between 5 minutes and 1 hour, preferably 20 minutes.

15. A method for finishing a hollow body (1) according to any one of claims 9 to 14, wherein the sealing step (E2) further comprises at least one linear cooling substep (024) taking place between a starting temperature corresponding to the final temperature of the preceding substep among the linear heating and holding steps, and an arrival temperature corresponding to the initial temperature of the following substep or to an outlet temperature TS, lower than the starting temperature, preferably the sealing step (E2) by annealing comprises a single linear cooling substep as the last substep and taking place between the temperature TF reached at the end of the last step among the linear heating and holding steps and an outlet temperature TS which is lower therein,said outlet temperature TS being greater than or equal to the minimum temperature TMIN and less than or equal to 100°C, preferably 70°C.

16. A method for enhancing a hollow body (1) according to any one of the preceding claims, which includes a relaxation step (02, E22, E23) including: - at least one linear temperature ramp substep (022, E22) between an initial ramp temperature greater than or equal to ambient temperature and less than or equal to 200°C, preferably of 150°C and a final ramp temperature between 400°C and 650°C; - at least one temperature maintenance substep (023, E23) at a plateau temperature between 400°C and 650°C; and in that the relaxation step (02) takes place for a duration between 10 minutes and 2 hours, preferably between 15 minutes and 1 hour.

17. A method for enhancing a hollow body (1) according to any one of the preceding claims, wherein the gas flow delivered through said at least one opening (30, 31) of said hollow body (1) has a flow rate between 50 liters per hour and 400 liters per hour and wherein the gas is selected from: air, oxygen, ozone, nitrogen, carbon dioxide, noble gas, hydrogen.

18. Hollow body (1) obtained by the process according to any one of claims 1 to 17, delimiting an internal volume (2), said hollow body (1) having a glass wall (10) and at least one opening (30, 31), said wall (10) having an internal face (20) situated opposite said internal volume (2), and having at least one layer of at least one coating (3, 4) sealed under gas flow at the level of at least a portion of said internal face (20).

19. Article comprising at least one hollow body (1) according to the preceding claim.

20. A manufacturing installation for a hollow body (1) according to claim 18 characterized in that it is designed and configured to implement the finishing process according to any one of claims 1 to 17 and in that it comprises: - an enclosure (50) suitable for receiving said hollow body (1); - at least one gas supply tube (60) inside said enclosure (50), suitable for delivering the gas flow through said at least one opening (30, 31) of said hollow body (1); - a gas flow supply system (70, 71), suitable for cooperating with the at least one gas supply tube (60).

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