WO2017207940A1

WO2017207940A1 - Process for forming a barrier coating at the surface of a container and related facility

Info

Publication number: WO2017207940A1
Application number: PCT/FR2017/051378
Authority: WO
Inventors: Pierre-Luc ETCHEPARE; Jingwei Zhang
Original assignee: Sgd S.A.
Priority date: 2016-06-02
Filing date: 2017-06-01
Publication date: 2017-12-07
Also published as: EP3464207A1; FR3052161A1; FR3052161B1; CN109562984A; CN109562984B

Abstract

The invention relates to a process for forming a barrier coating at the surface of a container comprising one glass wall delimiting a cavity for receiving a product, said glass wall having an inner face, said process comprising: - a step of placing said container in a chamber; - a step of vacuum purging said chamber until the pressure in the chamber reaches a predetermined purge pressure value; - a step of thermally activated chemical vapor deposition on at least one fraction of said inner face of a layer forming or helping to form said barrier coating, the value of the pressure prevailing in the chamber during said deposition step being lower than the atmospheric pressure and greater than said predetermined purge pressure value. Surface treatment of glass-walled containers.

Description

METHOD FOR FORMING A BARRIER COATING ON THE SURFACE OF A CONTAINER AND RELATED INSTALLATION

TECHNICAL AREA

The present invention relates to the general field of surface treatment processes and facilities and more particularly to methods and facilities for forming coating coatings on the surface of glass wall containers. The invention also relates to the technical field of glass wall containers for pharmaceutical and diagnostic applications.

The invention more specifically relates to a method of forming a barrier coating on the surface of a container comprising a glass wall delimiting a receiving cavity for a product intended to be administered to a human being or to an animal, said glass wall having an inner face facing said receiving cavity.

The invention also relates to an installation for forming a barrier coating on the surface of a container comprising a glass wall delimiting a receiving cavity for a product intended to be administered to a human being or to an animal, said glass wall having an inner face facing said receiving cavity.

PRIOR ART It is known to use for the storage of products and preparations for pharmaceutical or diagnostic use to glass containers such as bottles, bottles or ampoules. However, it has been observed that such preparations are likely to interact with the inner wall of these glass containers. In particular, in the case of containers of soda-lime glass or borosilicate glass, there is observed a phenomenon of migration of alkaline or alkaline-earth ions from the internal glass surface of the container to the product contained therein. Such a migration is particularly undesirable since it may in particular have the consequence to cause the modification of the pH of the contents and therefore its potential alteration, or even the dissolution or delamination of the glass.

Solutions have therefore been sought to enhance the chemical durability and the hydrolytic resistance of the glass in order to minimize the interactions between the glass container and its contents and, in particular, the migration in the content of alkaline ions from the glass. glass wall of the container. One of the well known solutions is to deposit on the inner face of the glass wall of the container, which defines a cavity for receiving the contents, a coating with a barrier property. Thus positioned between said inner face of the glass wall and the contents of the container, this barrier coating prevents, or at least very substantially limits, any interaction phenomenon, and in particular ion migration, between the glass wall and said content.

One of the methods commonly used for the implementation of this solution is to deposit chemically activated or plasma-assisted vapor phase (PECVD, PICVD) one or more protective oxide layers on the surface of the glass, from a gaseous reactive mixture containing a precursor of said oxide and a carrier gas. Such a process requires the implementation of technical means that can be expensive and complex, and allows, except to multiply in a costly and cumbersome manner said technical means, the treatment of only one container at a time. Therefore, this known method is hardly compatible with the simultaneous processing of a large number of containers in the context of a plant size and industrial rate, and generates a relatively high cost of manufacturing and processing containers.

Another known method for forming a layer coating coating on the surface of a glass container is to chemically vapor-deposit (CVD) one or more protective oxide layers on the glass surface. previously heated, from a reactive gaseous mixture projected towards the glass container and the opening of its neck. However, although thermally activated chemical vapor deposition processes are well controlled for the deposition of layers on flat substrates and are, in principle, less expensive and complex to implement than plasma-assisted processes, they still remain relatively easy to implement optimally for the treatment of a surface of complex geometry and having inaccessible areas such as, in particular, the inner face of a bottle-like container or bottle whose narrow neck tends to impede the good circulation reactive gas mixture. In order to overcome this difficulty, a method has been proposed in which a gaseous reactive mixture is injected into the receptacle whose internal glass surface is to be coated using a nozzle or similar device which is comes beforehand to introduce inside the container by its ring and the opening of its neck.

While such a process offers overall satisfaction, it nevertheless presents certain disadvantages. Indeed, this known process also requires independently treating each container, and quickly and accurately position the injection nozzle inside the container. This results in a relatively slow implementation and requiring significant adjustments. In addition, if the penetration of the gas phase inside the container to be treated is generally better than that obtained when the injection nozzle is disposed above the orifice of the container, the uniformity and homogeneity of the the deposited layer is still perfectible due in particular to a limited control of the diffusion of reactive gaseous species in the vicinity of the glass wall to be coated.

PRESENTATION OF THE INVENTION The objects assigned to the invention therefore aim at overcoming the disadvantages set out in the foregoing and at proposing a new process which makes it possible to easily and rapidly form a particularly uniform and homogeneous barrier coating on the inner face of the invention. the wall of a glass container of complex geometry, and in particular a narrow-necked container. Another object of the invention is to propose a new process which makes it possible to confer on a soda-lime or borosilicate glass container an excellent chemical and hydrolytic resistance with regard to its content, thus making it particularly suitable for the storage of pharmaceutical or diagnostic products. . Another object of the invention is to provide a novel method of forming a barrier wall surface of a glass wall container having at least one layer particularly adherent to said glass wall.

Another object of the invention is to propose a new method of forming a barrier coating on the surface of a glass-walled container that requires only relatively simple and standard industrial means for its implementation.

Another object of the invention is to provide a novel process which makes it possible to easily, cheaply and simultaneously treat a large number of glass wall containers. Another object of the invention is to propose a new process that is particularly reliable, robust and repeatable.

Another object of the invention is to provide a new facility for forming a barrier coating on the surface of a glass wall container which is particularly simple and economical to implement, while being reliable and robust. Another object of the invention is to propose a new installation which makes it possible to easily, simultaneously and cost-effectively process a large number of glass-walled containers.

Another object of the invention is to propose a new installation particularly suitable for the consecutive or simultaneous treatment of glass wall containers of any type and any size.

The objects assigned to the invention are achieved by means of a method of forming a barrier coating on the surface of a container comprising a glass wall defining a receiving cavity for a product to be administered to a human being or an animal, said glass wall having an inner face facing said receiving cavity, said method being characterized in that it comprises the following steps:

a step of disposing said container in an enclosure; a vacuum purge step of said chamber containing said container until the pressure in the chamber reaches a predetermined value of purge pressure;

a chemical vapor deposition step activated thermally on at least a fraction of said inner face of a layer forming or contributing to forming said barrier coating, the value of the pressure prevailing in the enclosure during said deposition step; being less than atmospheric pressure and greater than said predetermined purge pressure value.

The objects assigned to the invention are also achieved by means of an installation for forming a barrier coating on the surface of a container comprising a glass wall delimiting a receiving cavity for a product intended to be administered to a human being or to an animal, said glass wall having an inner face facing said receiving cavity, said installation being characterized in that it comprises at least:

an enclosure designed to receive inside said container in order to perform a thermally activated vapor phase chemical deposition step on at least a fraction of said inner face of a layer forming or contributing to forming said barrier coating; from a gaseous reactive mixture introduced into said enclosure;

a pumping device connected to the enclosure for sucking up the atmosphere inside the enclosure;

means for regulating the pressure prevailing in said chamber, which regulation means is designed to control said pumping device so that said pumping device first operates a vacuum purge of said chamber until the pressure in the latter reaches a predetermined value of purge pressure, then maintain the pressure in said chamber during said deposition step to a value below atmospheric pressure and greater than said predetermined purge pressure value. SUMMARY DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the invention will appear better on reading the description which follows, as well as with the aid of the appended figures, provided for purely explanatory and non-limiting purposes, among which:

FIG. 1 illustrates, in a diagrammatic sectional view, an example of a container provided with a barrier coating by means of a process according to the invention, which container is constituted in this case by a bottle preferably intended for to host a liquid pharmaceutical or diagnostic product;

FIG. 2 illustrates, in a schematic view, a preferred embodiment of the installation of the invention, which comprises at least one reaction enclosure designed to receive a plurality of containers and a pumping device controlled by a control means of pressure for the formation, according to the method of the invention, a barrier coating on the surface of the glass wall of these containers. BEST MODE OF REALIZING THE INVENTION

According to a first aspect, the invention relates to a process for forming a coating on the surface of a container 1 comprising a glass wall 2 delimiting a receiving cavity 3 for a product, or a substance, intended to be administered to a human being or an animal. Preferably, the process of the invention is an industrial process, intended to be implemented at relatively high rates, compatible with an industrial glass production.

The container 1 concerned is therefore preferably a hollow glass container. Preferably, said product or said substance is advantageously fluid, that is to say capable of flowing as for example a liquid substance, pasty (such as a liquid with a high degree of viscosity) or pulverulent. Preferably, the container 1 forms a container designed to contain a product or a liquid substance of pharmaceutical nature, for example a medicament, intended to be administered parenterally (general or locoregional) or to be ingested or absorbed by a drug. patient, or a liquid substance of a diagnostic nature, as for example a chemical or biological reagent intended to be brought into contact with a biological sample from a patient in order to obtain information in particular on the physiological or pathological state of said patient. By extension, said container 1 can be designed to contain a liquid substance of biological nature, or body fluid, te! such as blood, blood product or byproduct, urine, etc.

Although the application to the pharmaceutical and diagnostic fields is preferred, the invention is however not limited to containers for pharmaceutical or diagnostic use and also concerns, as an alternative alternative, a container 1 designed to contain a liquid substance, pasty or powdery for veterinary use, or for food use, or for cosmetic use (body perfume, cream or other).

In general, the container 1 is therefore advantageously intended to contain in its receiving cavity 3 a product, or a substance, intended to be administered to a human being or an animal. The container 1 may therefore have any form adapted to its function, and may be for example, as illustrated in Figure 1, in the form of a bottle, for example to contain a liquid product for pharmaceutical or diagnostic use. In this case, the glass wall 2 is advantageously formed by a glass bottom 2A, a glass side wall 2B which rises from and at the periphery of the bottom 2A and a neck 2C which closes the container 1 while providing an opening 4 filling / distribution for communicating the cavity 3 with the outside. Said opening 4 is optionally closed by a cap or a removable or perforable cap (not shown). However, it is perfectly conceivable that the container 1 affects any other form, and in particular a form without neck 2C such as for example a tube, bulb, syringe, or other, depending on the intended use. Such a container 1 made of glass, and in particular in the form of a bottle, can be obtained by any conventional glassmaking process (molded glass, blown glass, drawn glass, Veilo process or Danner process, etc.).

Preferably, the glass wall 2 of the container 1 delimiting the receiving cavity 3 is in the form of an integral piece which forms at the same time the bottom 2A, the side wall 2B and the neck 2C, so that the receiving cavity 3 is advantageously entirely delimited by a one-piece piece of glass, with the possible exception of the plug. However, it is perfectly conceivable that only a portion of the container 1 (for example only the side wall 2B) is made of glass. More precisely and as illustrated in FIG. 1, the glass wall 2 has an inner face 20 facing the receiving cavity 3 and an opposite outer face 21. The glass wall 2 thus advantageously forms a hollow and empty body whose inner face 20 delimits directly the cavity 3, which forms a fully closed, empty interior volume, with the exception of the outward opening 4 formed at the collar 2C whose section is in this case reduced with respect to the mean section of the cavity 3 (Figure 1). Said internal face 20 is therefore intended to come into contact with the contents of the container 1.

The term "glass" should be understood here in its conventional sense, and therefore refers to a mineral glass. As such, the glass wall 2 may therefore, for example, be soda-lime or borosilicate glass. In addition, the glass constituting the wall 2 is preferably transparent and colorless, but may alternatively be colored, for example by metal oxides, to protect the fluid substance contained within the container 1 from the effects of light, in particular in certain wavelength ranges (UV, etc.).

Since glass is usually considered to be impermeable to gases, the barrier property of the coating concerned by the invention preferably refers here to the ability of this coating to oppose the release of soluble substances extracted from the vitreous material of the wall 2 in the product. contained in the container 1 and, in particular, to limit or even prevent the passage of ionic species, such as for example alkaline and alkaline earth ions, through the barrier which it is intended to form between the inner face 20 glass and the contents of the container 1. Preferably, this barrier coating is colorless and transparent, so as not to modify, at least visually, with the naked eye, the colorimetric and / or transparency properties of the glass in which the wall 2 of the container is formed. Preferably, said barrier coating is intended to come into direct contact with the product contained in the container 1. As such, it advantageously fits between the inner face 20 of the glass wall 2 and the product in question. According to the invention, the process comprises at least one thermally activated vapor phase chemical deposition step on at least a fraction, and preferably all, of said inner face 20 of a layer 5 forming or contributing to form said barrier coating . This deposition step is preferably carried out from a gaseous reactive mixture, preferably hot, which comprises at least one precursor chemical compound of the component material of said layer 5 and a carrier gas. This gaseous reactive mixture is intended to be brought into contact during said deposition step with at least a fraction of said inner glass face 20, which is advantageously previously brought to a sufficient temperature (generally substantially greater than room temperature). to provide the energy necessary for the decomposition of the precursor transported to said inner face 20 by the carrier gas.

Preferably, said formed coating is composed of a single layer 5 and continuous in its thickness E, which may be more or less important, said layer 5 advantageously forming alone said barrier coating. However, it is perfectly conceivable without departing from the scope of the invention that this layer 5 in itself contributes to the formation of said barrier coating and that it can be, for example, itself covered with one or more different layers optionally deposited according to a different deposition technique, so as to form with this or these complementary layers said barrier coating.

In order to obtain a coating having a good hydrolytic resistance and offering a very good barrier property to the migration of ionic species from the glass wall 2 to the contents of the container 1, the layer 5 deposited according to the method of the invention is composed, that is to say formed predominantly and preferably integrally, a material based on a member selected from the group consisting of silicon Si, aluminum Al, titanium Ti, boron B , zirconium Zr, tantalum Ta or a mixture thereof. Advantageously, said layer 5 is more precisely composed of an oxide, a nitride or an oxynitride of an element chosen from the group consisting of Si silicon, Al aluminum, Ti titanium, boron B, zirconium Zr, tantalum Ta or a mixture thereof. The layer 5 is thus advantageously stable and inert from a chemical and biological point of view. So even more preferably, the layer 5 formed according to the process of the invention is composed of silica S102.

If aluminum-based materials, such as for example Al ₂ O ₃ alumina, can constitute a layer 5 offering good barrier properties to the migration of alkaline and alkaline-earth ions, there is however a risk of transfer. by these materials of ionic substances, in particular of ions A! ³⁺ , which may be able on the one hand to interact chemically with the contents of the container 1 and are, on the other hand, generally considered as toxic if not problematic for living organisms. As such, the aluminum-based materials may optionally be excluded from the list of materials preferably retained to form said layer 5, as could be otherwise materials based tin Sn or zinc Zn.

In order to form the desired barrier coating on the inner face 20 of the glass wall 2 of the container 1, the species constituting the reactive gas mixture must be able to penetrate into the receiving cavity 3 of the container 1 through the narrow opening 4 of the container 1. this last. However, it has been observed that a reactive gaseous mixture projected towards the container 1 and its opening 4 tends to flow along the outer wall 21 of the latter, without properly entering the cavity 3 and therefore without reacting. optimally at the inner wall 20. In fact, it has been noted that in normal atmospheric conditions, the atmosphere (in this case, ambient air) naturally present inside the cavity 3 of the container 1 at the time of deposition tends to oppose the good penetration of the reactive gas mixture. Thus, to counter this phenomenon without necessarily having to inject said gaseous reactive mixture directly into the cavity 3 by means of a nozzle or a similar device, the method of the invention comprises, first, a step of disposing (that is to say, introduction and introduction) of said container 1 in a chamber, preferably airtight. This enclosure is preferably designed to receive completely said container 1, that is to say so that said container 1 is advantageously completely included in said enclosure. The latter is thus advantageously intended to act as a reaction chamber in which said deposition step will take place. The deposition step is thus preferably performed on a static container 1 temporarily immobilized within said enclosure. According to the invention, the method also comprises, preferably after said step of disposing the container 1 in said chamber and before said deposition step, a step of vacuum purging said enclosure containing said container 1 until the pressure in the chamber reaches a predetermined value of purge pressure. During this purge step, the residual ambient air present inside the deposition chamber, as well as inside the receiving cavity 3 of the container 1 disposed therein, is thus sucked up. and evacuated out of the enclosure until the latter is placed under vacuum, that is to say until the pressure inside said enclosure is lower than the surrounding atmospheric pressure ( that is to say the ambient ambient pressure, which is for example substantially equal to

I 013.25 hPa when referring to the normal atmosphere). Preferably, said purge step is performed so as to place said chamber under a primary vacuum, that is to say under a vacuum level corresponding to a pressure prevailing in the chamber which is lower than the surrounding atmospheric pressure and can down to 0.01 hPa.

It has been observed during the development of the invention that the realization of such a vacuum purge step of the chamber prior to said deposition step makes it possible to obtain a better diffusion of the gaseous reactive mixture in the vicinity of inner face 20 of the glass wall 2 of the container, the vacuum conferring a better penetrating power to the reactive gas mixture, which promotes the good penetration of the latter through the opening 4 and its flow along said inner face 20, near the wall of the glass even when the opening 4 is relatively narrow. In addition, said step of purging ambient residual air inside the chamber before said deposition step advantageously makes it possible to avoid potential interactions of the gaseous reactive mixture with the chemical species present in the air (dioxygen, dinitrogen, water vapor, carbon dioxide, impurities, etc.). Indeed, these interactions can, on the one hand, modify the flow of the reactive gas phase and, on the other hand, lead to premature and detrimental chemical reactions in the gas phase. In addition, it has been noted that, when the pressure prevailing in the enclosure during said deposition step is lower than atmospheric pressure, undesirable gas phase reactions tend to be limited (especially due to bigger free average path of molecules in the gas phase), as well as the risks of contamination of the deposited layer 5. Moreover, in comparison with a CVD deposition step carried out at atmospheric pressure and the presence of ambient air, such a vacuum deposition step advantageously makes it possible to cover the entire surface of the inner face 20 of the container 1. On the other hand, if very low deposition pressures increase the diffusion coefficient of the species of the gaseous reactive mixture and make it possible to obtain a layer 5 more uniform in thickness, of higher purity and better covering the surface of the inner face 20, the deposition rate is slowed down. On the contrary, it is known that high pressures favor the reactions of species in the gas phase. Therefore, once said container 1 disposed within said chamber and the latter purged under vacuum during said purge step, said chemical vapor deposition step is performed, according to the invention, so as to that the value of the pressure prevailing in the chamber during said deposition step is less than the atmospheric pressure and greater (strictly) than said predetermined value of purge pressure. The value of the pressure prevailing in the chamber during said deposition step, not necessarily constant, is thus advantageously strictly between the value of the atmospheric pressure and said predetermined value of purge pressure. More specifically, it has been observed during the development of the process of the invention that, in the context of an industrial application of said process and according to the composition of the layer 5 to be deposited and / or the nature of the precursor or depending on the geometry of the container 1 to be treated, a good compromise between the quality of the deposited layer 5, especially in terms of homogeneity and absence of contamination, the deposition rate and the good penetration / evacuation of the reactive species and products of the reaction in the cavity 3 of the container 1 is reached when said vacuum purge step is preferably carried out until the pressure in the chamber reaches a predetermined value of purge pressure less than or equal to 1 hPa and when the value the pressure prevailing in the chamber during said deposition step is, more preferably, substantially between 20 and 980 hPa.

Thus implementing a relatively low vacuum within the chamber relative to the surrounding atmospheric pressure, the method of the invention is therefore particularly easy to implement, reliable and robust in industrial environment, not requiring complex and expensive pumping and sealing techniques. I! Thus, in a particularly advantageous manner, the easy definition of large enclosure dimensions makes it possible to easily and simultaneously process a very large number of containers 1, which can moreover be of varied size and geometry.

During said deposition step, the possible excess of unreacted gaseous reactant mixture and gaseous by-products of the reaction of said reaction mixture must be able to be discharged through said narrow opening 4 without interfering with the penetration of the reaction mixture. reactive gas mixture. Therefore, the flow profiles and flow rate of the gaseous reactant mixture within the vessel 1 must be accurately controlled and controlled to avoid turbulence phenomena and to ensure a uniform distribution of species forming the reaction mixture in the vicinity of the vessel. the wall 2 of the container 1. Indeed, the inner face 20 of the container 1 must preferably be completely covered by said barrier coating and the thickness E of the layer S deposited on the inner face 20 of the wall 2 must be the most uniform possible. As such, the value of the pressure prevailing in the chamber during said deposition step is preferably kept substantially constant, advantageously finely regulated around a predefined deposition pressure value which is preferably within the pressure range. deposit mentioned above. To do this, the chamber is advantageously connected to a pressure regulation system, consisting for example of a so-called butterfly valve and a pressure sensor. As a function of a setpoint pressure, and for a rate of introduction of the constant gaseous reactant mixture, the excess gaseous reactive mixture and the reaction products thereof present in the chamber are sucked up and discharged in such a way as to maintain the pressure in the chamber at said predefined deposition pressure, after a possible transient regime related to the introduction of said reactive gas mixture. It has been observed, moreover, that the maintenance of a substantially constant deposition pressure advantageously makes it possible to control the kinetics of the reaction leading to the deposition of the layer 5, in particular for relatively long gaseous reaction mixture introduction times. (typically of the order of 60 seconds), advantageously avoiding the creation of pressure gradients in the enclosure during deposition. Indeed, such pressure gradients could cause the reaction of the precursor in the reactive gas mixture, and not in contact with the face It is apparent from the foregoing that the invention thus makes possible and relatively easy the integral and homogeneous coating of the inner face of the container 1, and thus lead to the formation of a powdery layer on the glass wall 2. 20 of containers 1 provided with a particularly narrow opening 4. Preferably, said depositing step is carried out from a gaseous reactive mixture which comprises a metallo-organic precursor (or "organometallic" precursor), that is to say a chemical compound comprising at least one covalent bond between a carbon atom and a metal or a metalloid (such as for example silicon Si). In this respect, the process of the invention therefore advantageously relates to a gas phase deposition step of the MOCVD ("metalorganic chemical vapor deposition") type. Even more preferably, this precursor is selected from the group consisting of tetraethyl orthosilicate (TEOS), hexamethyldisiloxane (HMDSO) and tetramethyl orthosilicate (T OS), as a precursor for silica deposition S102. It is of course quite conceivable, without departing from the scope of the invention, to use a precursor of a different kind, organometallic or otherwise, as a precursor for the deposition of a layer of different composition and, for example, composed of an oxide, a nttrure or an oxy-nitride of a metal other than silicon.

In the case where the precursor, whether organometallic or not, is in solid or liquid form at ambient pressure and temperature, the storage temperature Tstock of the precursor must be lower than its sublimation temperature T _SU biim or evaporation Té _vap . In addition, the transport temperature T _tra nsp from the precursor to the deposition chamber will preferably be at least equal to its sublimation temperature T _sub rim or evaporation T _eV ap and strictly lower than the decomposition temperature Tdecom precursor , so as to avoid, on the one hand, the condensation of the precursor in the supply lines of the deposition chamber and thus the fouling of the latter and, on the other hand, the early reaction of decomposition of the precursor in the gaseous reactive mixture .

Preferably, said gaseous reactive mixture comprises a neutral carrier gas which is nitrogen N ₂ or argon Ar, this carrier gas having in particular the function of transporting the precursor to the hot surface in contact with which it is desired to ie to react, in this case in contact with at least the inner face 20 of the glass wall 2 of the container 1.

In a particularly advantageous manner, said deposition step is carried out from a gaseous reactive mixture which is introduced into said enclosure sequentially and discontinuously during the deposition step. According to this particular embodiment, the gaseous reactive mixture is injected into the reaction chamber, which has been previously purged under vacuum during said purge step so as to extract the residual ambient air, at a controlled flow rate and during a given time e relatively short (typically of the order of 10 seconds), chosen in particular according to the surface area of the inner face 20 to be coated and the thickness E of the layer 5 that seeks to deposit. Then the introduction of the gaseous mixture is interrupted for a time t ₂ , so as to allow time for the amount of reactive gaseous mixture injected to react in contact with the hot inner face. This sequence of introduction of the reactive gas mixture can be repeated advantageously several times until the desired amount of gaseous reactive mixture is injected into the chamber. Preferably, each introduction sequence of the gaseous reactive mixture is advantageously followed by a vacuum purge operation of the chamber, that is to say an operation during which the atmosphere present in the atmosphere is vacuumed. enclosure (composed in this case of a possible excess of unreacted gaseous reaction mixture and gaseous by-products of the reaction of said reaction mixture) and restore the vacuum in the latter, preferably until reaching a value pressure identical to said predetermined pressure value prevailing in the chamber at the end of said purge step and before the injection of the gaseous mixture. The forming method of the invention is then, according to this particular embodiment, advantageously composed of a plurality of successive purge and deposition steps. It is also also possible, in this particular embodiment, to keep the pressure prevailing in the reaction chamber substantially constant during each introduction sequence of the gaseous reactive mixture, for the reasons mentioned above. Thus, thanks to such a sequential and discontinuous introduction mode of the gaseous reactive mixture in the chamber during the deposition step, better control of the amount of precursor injected into the chamber and ensures also from the absence of material accumulation and overpressure inside the container 1 during the deposition step, which would interfere with the good flow into / out of the reactive gas mixture through the narrow opening 4 of the container 1 The process is thus particularly precise, reliable and repeatable. Whether said reactive gaseous mixture is introduced continuously or discontinuously and sequentially into the deposition chamber, it is furthermore optionally possible to envisage, without departing from the scope of the invention, that its components (in particular at least one of said carrier and precursor gases) is introduced separately or partially separated into said enclosure during said deposition step. In this particular configuration, once the container 1 disposed in the chamber and the latter purged under vacuum, it is first introduced into the chamber of the carrier gas to reach a predefined deposition pressure value, which is less than atmospheric pressure and greater than said predetermined purge pressure pressure value, and preferably between 20 and 980 hPa. The reactive gas mixture comprising the precursor, or even the precursor alone in the gas phase, is then introduced into the chamber so as to mix with the carrier gas already present in order to form the layer 5 in contact with the surface of the 2 hot glass wall and in particular in contact with the inner face 20 of the latter. By setting the rate of introduction of the gaseous reactive mixture (or of the precursor alone) sufficiently low and by precisely regulating the pressure prevailing within the chamber so as to keep it substantially constant and equal to said predefined deposition pressure value, it is advantageously possible to avoid as much as possible the creation of pressure gradients within the enclosure, source of premature and undesirable reactions of the precursor in the gaseous reactive mixture.

In order to guarantee a good compromise between the performance of the barrier coating formed in terms of hydrolytic resistance and the compatibility of the formation process with industrial operating conditions, the deposition time of the layer 5 within the enclosure during the deposition step, ie the effective reaction time of the gaseous reactive mixture in contact with the glass wall 2, and in particular of its hot inner surface, is preferably substantially between 9 s and 30 min, from more preferably between 10 s and 10 min, depending on the nature of the precursor used and the thickness of the desired layer 5.

Preferably, the thickness E of the layer 5 deposited on the inner face 20 of the container 1 according to the process of the invention is, in this case, substantially between 1 and 500 nm. The tests carried out as part of the development of the invention have shown that this range of values, which can of course be adapted according to the characteristics of the container 1 to be coated and the chemical composition of the deposited layer, makes it possible to obtain a barrier coating that is particularly effective in preventing the migration of ionic species, in particular of alkaline or alkaline-earth ions, from the glass wall 2 to the product contained in the cavity 3 of the container 1, while limiting the risk of delamination and cracking of the coating, especially during a possible subsequent sterilization step.

In order to thermally activate the chemical vapor deposition reaction by supplying the energy necessary for the decomposition of the precursor in contact with said inner face 20, the barrier coating formation process advantageously comprises, prior to the deposition step, a step of heating the container 1 and its glass wall 2. During this heating step, the temperature of the glass wall 2 of the container 1 is raised so that said deposition step is carried out on a glass wall (2) heated to a temperature substantially between 125 ° C and 600 ° C and, even more preferably, particularly in the case of the deposition of a layer 5 composed of silica Si0 ₂ , at a temperature substantially between 350 ° C and 550 ° C. This heating step is preferably carried out prior to the introduction of the container 1 within the deposition chamber, for example by passing the container 1 under a heating arch. It is advantageously carried out using a primary heating device by infra-red or microwave and preferably without convection, so as to heat the container 1 uniformly while avoiding the movement of ambient dust and their deposition on the surface of the hot glass. Alternatively, the heating step can be performed directly in the enclosure itself, once the container 1 placed in it and before the completion of said purge and deposition steps. In particular, in the case where the heating step is carried out outside the deposition chamber, the latter can advantageously be provided with a device for secondary heating, for example an induction heating means or microwaves, so as to maintain substantially constant the temperature of the glass wall 2 during the deposition step, despite the temperature variations that could cause vacuum purging the chamber prior to the deposition step and introducing the gaseous reactant mixture during said deposition step.

Preferably, the process comprises, prior to the deposition step and, more preferably, before the purge step of the chamber, a step of washing the container 1 and in particular its glass wall 2. This washing step is preferably carried out with ultra pure water, that is to say a water which advantageously contains only H ₂ O molecules, and H ⁺ and OH ^" ions in equilibrium, or even more preferably , water for injection (EPPI or "Aqua ad iniectabilia"), as defined in particular by the European Pharmacopoeia, that is to say a water intended for the preparation of medicinal products for parenteral administration or water intended for dissolving or diluting substances or preparations for parenteral administration (PPI sterilized water) During this washing step, the water is advantageously introduced into the receiving cavity 3 of the container 1 so that at least come in contact with the inner face 20 of the glass wall 2, and is then extracted, for example by suction. This step is advantageously repeated several times, preferably three times, to ensure optimal washing performance. This washing step is preferably followed by a drying step during which the container 1 is dried, preferably by a jet of dry compressed air. Before or alternatively at this washing step with water, the container 1 can be cleaned in an acetone bath under ultrasound to degrease at least its inner face 20, and then in an ethanol bath under ultrasound. In addition, the container 1 may alternatively be dried under a flow of neutral gas, for example under an Ar argon flow. This washing step, optionally followed by a drying step, is important to prepare the inner face 20. container glass 1 before deposit, avoid the presence of dust and contaminants and thus ensure good adhesion of the barrier coating. Preferably, said washing step and, optionally, said drying step are carried out before the heating step described above. It should be noted that the method of the invention relates preferably to a container 1 which has been subjected, prior to the deposition step, to a primary annealing step intended to relax the residual stresses of the glass after forming of said container 1. Such a primary annealing step, well known as such, can be carried out in a conventional annealing arch. Thus, the layer 5 intended to form or contribute to forming the barrier coating is preferably deposited, during the deposition step, on the inner face 20 of a glass wall 2 substantially free of internal stresses and surface area. to the forming of said container 1. Even more preferably, the method of the invention relates to a container 1 having undergone a primary annealing as described above, as well as a preliminary operation of inspection / control and sorting to discard any containers 1 with manufacturing defects.

Preferably, the method further comprises a secondary annealing step of the container 1 consecutive to the deposition step of the layer 5. The coated container 1 is thus extracted from the deposition chamber and advantageously placed in an annealing arch secondary to be annealed and gradually cooled. Since the stresses in the deposited layer are high at the end of deposition, this secondary annealing step allows the relaxation of these stresses and the improvement of the hydrolytic resistance properties of the glass wall 2 of the container 1. Advantageously, the temperature of the annealing is preferably between 500 and 580 ° C and the cooling rate preferably between 10 and 30 ° C / min. These ranges of values may possibly be adjusted according to the composition of the layer 5.

Preferably, the method of the invention comprises, at the end of said deposition step and, more preferably, at the end of the secondary annealing step, a step of inspection and control of the physical characteristics. chemical and mechanical of the deposited layer 5 and the barrier coating formed on the surface of the container 1.

The process of the invention is advantageously carried out in recovery, that is to say outside the manufacturing line of the container 1, which extends within the meaning of the invention of the "hot end" to the "cold end". Unlike a process which would be carried out in line and during which the barrier coating would then be formed on the parade, that is to say on moving containers, the fact of carrying out said process in recovery allows advantageously depositing a layer 5 on the inner face 20 of one or more containers 1 in a static configuration, by avoiding the constraints of cadence imposed by the productive means arranged upstream in the line. It results in a more robust and reproducible process, the recovery treatment advantageously, compared to an online treatment, a better control of the amount of precursor introduced and the flow of the reactive gas mixture in the receiving cavity 3 of the container 1 to be treated. According to this preferred embodiment, the process is therefore advantageously carried out using a specific specific installation, preferably conforming to that described below, situated at a distance from the manufacturing line of the container 1, and not directly integrated. to this last. This advantageously allows, moreover, to treat only part of the containers 1 from the production line, at a rate possibly lower than the average rate of said line. It is therefore possible to implement relatively long deposition times with respect to the rate of the production line, leading to the formation of a barrier coating of better quality and in particular less sensitive to delamination, without calling in question the general rhythm of that line.

The invention thus makes it possible, thanks to a specific layer deposition process under atmospheres and controlled pressures, to form a barrier coating on the surface of the inner face 20 of a glass container 1 which is particularly effective in preventing the transfer of ions from container 1 to the product it contains. Thanks to the process of the invention, it is possible, from conventional soda-lime or borosilicate glass containers, to obtain, in a simple, fast, inexpensive and repeatable manner, containers 1 which are particularly well suited to packaging and storing products as well. sensitive than pharmaceutical or diagnostic products.

The invention also relates as such to an installation 6, preferably industrial, for the formation of a barrier coating on the surface of a container 1 advantageously in accordance with the description which is made above, it is that is to say a container comprising in particular a glass wall 2 delimiting a reception cavity 3 for a product intended to be administered to a human being or to an animal, said glass wall 2 having an internal face 20 located opposite of said receiving cavity 3. Advantageously provided to allow the implementation of the method of the invention described above, and as illustrated in FIG. 2, said installation 6 of the invention comprises at least, on the one hand, an enclosure 7 designed, in particular in terms of dimensions, to receive within it said container 1 and, preferably, a plurality of containers 1. Preferably, said enclosure 7 is provided to receive integrally said container or containers 1, that is to say that these or these are advantageously totally included in said enclosure 7. Preferably provided with airtight doors and vacuum by which said container 1 can be introduced and extracted from the enclosure 7, the latter forms a reaction chamber 8 advantageously hermetic for carrying out a thermally activated vapor phase chemical deposition step on at least a fraction of the inner face 20 of the glass wall 2 of the recipi ent 1 of a layer 5 forming or contributing to form said barrier coating from a reactive gas mixture introduced into said enclosure 7. Advantageously as described above, said layer 5 is composed of a material based on a member selected from the group consisting of Si silicon, aluminum Al, titanium Ti, boron B, zirconium Zr, tantalum Ta or a mixture thereof. Preferably, said layer 5 is more precisely composed of an oxide, a nitride or an oxynitride of an element chosen from the group consisting of Si silicon, aluminum Al, titanium Ti, boron B, zirconium Zr, tantalum Ta or a mixture thereof.

The installation 6 comprises at least, on the other hand, a pumping device 9 connected to the enclosure 7 for sucking up the atmosphere inside the latter, as well as a regulation means 10 for the pressure prevailing in the said enclosure 7. According to the invention, said regulation means 0 is designed to control said pumping device 9 so that the latter operates first, and prior to said deposition step, a vacuum purge said enclosure 7 until the pressure in the latter reaches a predetermined value of purge pressure, then maintain the pressure in said chamber 7 during said deposition step to a value below atmospheric pressure and above (strictly) at said predetermined purge pressure value. The value of the pressure prevailing in the chamber during said deposition step, which is not necessarily constant, is thus maintained. advantageously strictly between the value of the atmospheric pressure and said predetermined value of purge pressure.

Connected preferably to the pumping device 9 and including, for example, a so-called butterfly valve and a pressure gauge connected to a PiD regulator, said regulating means 10 is advantageously designed and parameterized so that said predetermined pressure value of purge corresponds to a primary vacuum level, that is to say a pressure in said chamber 7 between the value of the surrounding atmospheric pressure (which is generally substantially equal to 1013.25 hPa) and about 0, 01 hPa and, even more preferably, so that said predetermined value of purge pressure corresponds to a pressure less than or equal to 1 hPa. It is further preferably designed and parametered so as to maintain the pressure prevailing in said enclosure 7 during said deposition step to a value substantially between 20 and 980 hPa. It is perfectly possible here that said regulation means 10 allow a variation of the pressure prevailing in said enclosure 7 during said deposition step in this value range. However, particularly advantageously, said regulating means 0 is instead designed to maintain substantially constant, for example around a predefined value of deposition pressure in said range of value, the value of the pressure prevailing inside. of said enclosure during said deposition step.

Controlled by said regulating means 10, said pumping device 9 thus advantageously makes it possible to pump the ambient air present inside the reaction chamber 8, and in particular into the cavity 3 of the container 1 to be treated, in order to establish the vacuum before deposit. In a second step, during the deposition step, the pumping device 9 then makes it possible to extract a possible excess of reactive gas mixture, and the gaseous by-products of the decomposition reaction of the precursor contained in said reaction mixture. gaseous. Preferably, said pumping device 9 comprises a pump of the primary type (or primary pump), advantageously capable of making it possible to reach a level of vacuum in said enclosure 7 in accordance with the values and ranges of value mentioned above. More preferably, and as illustrated in FIG. 2, the aspiration of the atmosphere inside the enclosure 7 by the pumping device 9 is done by one or more orifices formed through the enclosure 7 and opening under the container 1, so as to optimize the flow of the reactive mixture within the cavity 3 and along the inner face 20 of the container 1.

The installation 6 further comprises, preferably, a primary heating device (not shown), advantageously positioned upstream of the enclosure 7, and intended to raise the temperature of the glass wall 2 of the container 1, and thus of its inner face 20, so that said depositing step is performed on a glass wall 2, and in particular on the inner face 20 thereof, brought to a temperature substantially between 125 ° C and 600 ° C and, even more preferably, in particular in the case of the deposition of a layer 5 composed of silica SiO ₂ , at a temperature substantially between 350 ° C and 550 ° C. For example of the arch type, this primary heating device preferably comprises heating means by infra-red or microwave and preferably still without convection, so as to heat the container 1 uniformly while avoiding the movement of dust ambient and their deposit on the surface of the hot glass. Of course, depending on the distance between said primary heating device and the chamber 7, it is understood that the primary heating device may be designed to raise the temperature of the glass wall 2 of the container 1 to a temperature higher than those of aforementioned ranges to compensate for a possible cooling of the container 1 between its passage in the primary heating device and its introduction into the chamber 7, and thus ensure that when the container 1 is disposed within the chamber 1 to be subjected to said deposition step, the temperature of its glass wall 2 and in particular of the inner face 20 thereof is well within the aforementioned temperature ranges.

Advantageously, the installation 6 also comprises a means of preparation (not shown) of said gaseous reactive mixture, which comprises a metallo-organic precursor. In the case where this metallo-organic precursor is solid or liquid at ambient pressure and temperature, said preparation means advantageously includes a device for sublimation or evaporation of said precursor and mixing of said precursor sublimated or evaporated with a neutral carrier gas, for example nitrogen N ₂ or Ar argon. Said means for preparing the gaseous reactive mixture is further advantageously designed so that the storage temperature T _s t _0C k of the precursor is permanently lower than its storage temperature. sublimation T _sub iim or Evaporation Té _is p The preparation means further comprises, preferably, the heat regulation means designed so that the transport temperature T _tr ansp precursor to deposit i'enceinte 7 is preferably at least at its sublimation temperature T _SU bum or evaporation Tévap precursor and strictly less than the Tdécomp decomposition temperature of the precursor. As mentioned above, this avoids on the one hand the condensation of the precursor in the supply lines 11 of the chamber 7 deposition and thus the fouling of the latter and secondly the early reaction of decomposition of the precursor in the gaseous reactant mixture. In order to allow and facilitate the introduction of the reactive gas mixture into the chamber 7 and the receiving cavity 3 of the container 1, the installation 6 further comprises an injection system 12 provided with at least a nozzle 13, and preferably a plurality of nozzles 13, for example of the diaphragm type, or a single hand shower, centered above the container or containers 1 to be treated. In addition, the plant 6 of the invention particularly advantageously comprises a sequential and discontinuous introduction means (not shown) of the gaseous reactive mixture in said enclosure 7, which sequential and discontinuous introduction means is preferably connected to said control means 10. As such, the installation 6 comprises, for example, upstream of the injection system 2 with nozzle (s) 13 described above, a first solenoid valve 14A (piezoelectric type or other) associated with the system injection 12 of the reactive gas mixture. During a given time ti, relative in particular to the area of the inner face 20 to be coated, this first solenoid valve 14A can be held open position, so as to let the gaseous reaction mixture flow inside the chamber 7 according to a predefined flow rate. At the end of the time t-ι, the first solenoid valve 14A is then closed to stop the flow of the reactive gas mixture in the chamber 7 and the container 1.

As envisaged above, it is also possible to provide during the time t ₂ during which said first solenoid valve 14A is closed, a vacuum purge operation of the enclosure, that is to say an operation during the atmosphere present in the chamber (composed in this case of a possible excess of unreacted gaseous reactant mixture and gaseous by-products of the reaction of said reaction mixture) is sucked up and the vacuum is restored in the latter, preferably until reaching a value of pressure identical to said predetermined pressure value prevailing in the enclosure at the end of said purge step and before the injection of the gaseous mixture. The installation 6 can then advantageously comprise a second solenoid valve 14B, installed upstream of said pumping device 9. This second solenoid valve 14B is then designed to be closed (partially or totally) at the beginning of the time ti, once the vacuum level has been reached. desired to be established within the chamber 7, and to be fully open at the beginning of the time t ₂ so as to allow the evacuation of the reaction by-products and the unconsumed gaseous reactant mixture to the pump of the pumping device 9 .

Preferably, the installation 6 comprises a washing means, and optionally a drying means, (not shown) of the container 1 intended to subject the latter to a washing / drying step advantageously in accordance with the description given therein. before, that is to say, preferably a washing step with ultra pure water or, even more preferably, water for injection (EPPI or "Aqua ad iniectabilia"). These washing means and, optionally, drying are preferably positioned upstream on the one hand of the enclosure 7 and, on the other hand, of the primary heating device so as to advantageously allow the washing / drying of the container 1 before its heating by said primary heating device and prior to its introduction and its disposition within the enclosure 7,

The installation 6 preferably comprises a secondary annealing arch (not shown) intended to receive the container 1 extracted from the chamber 7 after deposition of the layer 5 to submit it to a secondary annealing step as described above.

Preferably, the installation 6 also comprises a device for inspection and control (not shown) of the physicochemical and mechanical characteristics of the layer deposited and the barrier coating formed on the surface of the container 1.

Finally, the installation 6 is advantageously designed to be implemented in recovery, that is to say outside the manufacturing line of the container 1 and to operate independently and independently of said production line. Ultimately, the installation 6 of the invention, which allows the formation of a barrier coating on the surface of a container 1 with a glass wall 2, is relatively simple and inexpensive to manufacture and to implement, not making only relatively standard technical means that can easily be used in industrial conditions. Once appropriately dimensioned, it is also particularly well suited to the consecutive or simultaneous treatment of large quantities of glass wall containers, which can be of any type (bottles, jars, bottles, tubes, etc.) and various sizes.

POSSIBILITY OF INDUSTRIAL APPLICATION

The invention finds its industrial application in the design, manufacture and surface treatment of glass wall containers, for example intended for pharmaceutical and diagnostic applications.

Claims

A method of forming a barrier coating on the surface of a container (1) comprising a glass wall (2) defining a receiving cavity (3) for a product to be administered to a human or an animal, said glass wall (2) having an inner face (20) facing said receiving cavity (3), said method being characterized in that it comprises the following steps:

a step of disposing said container (1) in an enclosure;

a vacuum purge step of said enclosure containing said container (1) until the pressure in the chamber reaches a predetermined value of purge pressure;

a step of chemical vapor deposition thermally activated on at least a fraction of said inner face (20) of a layer (5) forming or contributing to form said barrier coating, the value of the pressure prevailing in the chamber during said deposition step being less than atmospheric pressure and greater than said predetermined purge pressure value.

2- Method according to the preceding claim characterized in that said purging step is performed so as to place said enclosure under primary vacuum. 3- Method according to the preceding claim characterized in that said vacuum purge step is carried out until the pressure in the chamber reaches a predetermined value of lower purge pressure or equal to 1 hPa.

4. Process according to any one of claims 1 to 3 characterized in that the value of the pressure prevailing in the chamber during said deposition step is substantially between 20 and 980 hPa. 5. Process according to any one of the preceding claims, characterized in that the value of the pressure prevailing in the chamber during said deposition step is kept substantially constant.

6. Process according to any one of the preceding claims, characterized in that the deposited layer (5) is composed of an oxide, a nitride or an oxynitride of an element chosen from the group consisting of silicon. If, aluminum Al, titanium Ti, boron B, zirconium Zr, tantalum Ta, or a mixture thereof.

7- Process according to any one of the preceding claims, characterized in that said deposition step is carried out from a gaseous reactive mixture comprising a metallo-organic precursor.

8- Method according to the preceding claim characterized in that the precursor is selected from the group consisting of tetraethyl orthosilicate (TEOS), hexamethyldisiloxane (HMDSO) and tetramethyl orthosilicate (TMOS), as a precursor for the deposit silica Si0 ₂ .

9- Process according to any one of the preceding claims characterized in that said deposition step is carried out from a gaseous reactive mixture comprising a neutral carrier gas which is N ₂ dinitrogen or argon Ar.

10- Process according to any one of the preceding claims characterized in that said deposition step is carried out from a gaseous reactive mixture which is introduced into said chamber sequentially and discontinuously during said deposition step.

11- Method according to the preceding claim characterized in that each sequence of introduction of the reactive gas mixture in said chamber is followed by a vacuum purge operation of said enclosure. 12- Process according to any one of the preceding claims characterized in that said deposition step is carried out from a gaseous reactive mixture whose components are introduced separately or partially separated in said chamber during said deposition step . 13- Method according to any one of the preceding claims characterized in that it comprises, prior to the deposition step, a step of washing said glass wall (2) with ultra pure water or water for injectable preparation, preferably followed by a drying step in dry air.

14- Method according to any one of the preceding claims characterized in that it comprises, prior to said deposition step, a step of heating said container (1) so that said deposition step is carried out on a wall glass (2) heated to a temperature substantially between 125 ° C and 600 ° C, and preferably substantially between 350 ° C and 550 ° C.

15- Method according to any one of the preceding claims characterized in that said container (1) has been, prior to said deposition step, a primary annealing step to relax the residual stresses of the glass after forming said container (1).

16- Method according to any one of the preceding claims characterized in that it comprises a secondary annealing step of the container (1), subsequent to said deposition step of said layer (5).

17- Method according to any one of the preceding claims, characterized in that it is carried out in recovery, off-line manufacturing container (1). 8- Installation (6) for forming a barrier coating on the surface of a container (1) comprising a glass wall (2) delimiting a receiving cavity (3) for a product intended to be administered to a being human or to an animal, said glass wall (2) having an inner face (20) facing said receiving cavity (3), said installation (6) being characterized in that it comprises at least: an enclosure (7) adapted to receive therein said container (1) for carrying out a thermally activated vapor phase chemical deposition step on at least a fraction of said inner wall (20) of the glass wall (2) a layer (5) forming or contributing to form said barrier coating from a reactive gas mixture introduced into said enclosure (7); a pumping device (9) connected to the enclosure (7) for sucking the atmosphere inside the enclosure;

means (10) for regulating the pressure in said chamber (7), said regulating means (10) being adapted to control said pumping device (9) so that said pumping device (9) first operates a purge under vacuum of said chamber (7) until the pressure therein reaches a predetermined value of purge pressure, then maintain the pressure in said chamber (7) during said deposition step to a value less than the atmospheric pressure and greater than said predetermined purge pressure value.

19- Installation (6) according to the preceding claim characterized in that said regulating means (0) is designed to maintain substantially constant the value of the pressure inside said chamber (7) during said depositing step . 20- Installation (6) according to claim 18 or 19, characterized in that it comprises a means for preparing said reactive gas mixture, which comprises a metallo-organic precursor.

21- Installation (6) according to any one of claims 18 to 20 characterized in that it comprises means for sequential introduction and discontinuous said reactive gas mixture in said enclosure (7).

22- Installation (6) according to any one of claims 18 to 21 characterized in that it comprises a means for washing said glass wall (2) with ultrapure water or water for injection. 23- Installation (6) according to any one of claims 18 to 22 characterized in that it comprises a means for heating the container (1) designed so that said depositing step is performed on a glass wall (2) heated to a temperature substantially between 125 ° C and 600 ° C, and preferably substantially between 350 ° C and 550 ° C.