Polymer substrate composite barrier film based on deposition-heat treatment, method and application

Abstract

The invention relates to a polymer substrate composite barrier film based on deposition-heat treatment and a method and application thereof, and relates to the technical field of new materials. According to the method, a deposition method is combined with a fusible glass material, and the deposition method and a heat treatment process are utilized, so that the requirements of enamel and glass lining of an organic polymer substrate on the heat resistance of a polymer are greatly reduced, and the selection range of the polymer substrate and the glassy material is widened; according to the technology, the characteristics of atomic thermal motion, melt self-leveling and the like of fusible glass during heating are ingeniously utilized, residual gaps in a deposited inorganic layer are filled with the fusible glass by setting a heat treatment process, then the fusible glass is converted into a coherent defect-free or few-defect layer structure, the problem of residual defects during preparation of the barrier film by an existing PVD / CVD method is effectively solved, and the barrier film is prepared. The barrier layer with high density, high uniformity and sufficient gap filling can be obtained at a relatively low temperature, and the strict requirements for deposition preparation and deposition conditions for achieving the ultrahigh barrier performance are remarkably reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of new materials, and in particular to a polymer substrate composite barrier film based on deposition-heat treatment, a method and an application thereof. Background Art

[0002] High-barrier films are widely used in electronic packaging, flexible displays, food and pharmaceutical packaging, and other fields. To obtain high-barrier films with excellent barrier properties, researchers have explored various methods.

[0003] Currently, common methods for producing high-barrier films include physical vapor deposition (PVD) and chemical vapor deposition (CVD). PVD involves a physical process in which raw materials are vaporized and condensed onto a substrate surface to form a thin film. Representative techniques include thermal evaporation, electron beam evaporation, and sputtering. These methods share a common characteristic: relatively simple equipment, but the deposition process is difficult to precisely control, and defects are prone to forming in the film layer, resulting in low barrier properties.

[0004] Chemical vapor deposition (CVD) involves the use of gaseous precursors to generate a chemical reaction on a substrate surface, producing the desired thin film. Representative techniques include plasma-enhanced chemical vapor deposition (PECVD) and atomic layer deposition (ALD). Compared to PVD, CVD produces films with higher density and uniformity, making it a common method for producing high-barrier and ultra-high-barrier films. However, CVD requires stringent control of equipment and process parameters, resulting in relatively high costs.

[0005] In recent years, with the industry's increasing demand for improved composite film manufacturing efficiency, the above-mentioned PVD and CVD methods have achieved roll-to-roll continuous production to a certain extent. However, in actual production applications, the following problems still exist:

[0006] (1) The film layer prepared by PVD method has insufficient density and limited barrier performance. Even if multi-layer deposition is used, it is difficult to meet the needs of high-end applications.

[0007] (2) Although the CVD method can produce high-quality barrier layers, it is relatively expensive. In particular, ALD, although each time the raw material precursor gas enters the chamber, a dense layer structure can be formed on the substrate surface, it requires repeated pumping of gas in and out to purge the chamber, resulting in a slow deposition rate, high energy consumption, and expensive equipment, making it difficult to achieve low-cost mass production.

[0008] (3) Ultra-high barrier films generally rely on organic-inorganic laminated structures. The organic layer plays a smoothing role, preventing the inorganic material from growing in a self-modeled manner after a long deposition period, which can lead to a decrease in the density of the layer structure. The laminated structure reduces the overall permeability coefficient of the composite film by extending the diffusion path of molecules such as water vapor and oxygen in the composite film.

[0009] In the applicant's previous research, they developed polymer-based "ceramic enamel" and "glass enamel." However, the firing temperatures for the inorganic porcelain and glassy layers are very high, requiring the polymer to possess strong heat resistance. This limits the choice of polymer and inorganic materials, and consequently, the development of high-performance composite membranes. Furthermore, inorganic powder layers based on glass paste or glass powder coatings lack uniformity, making the resulting composite membranes difficult to use as substrates for micro- and nanoelectronic devices, which require highly uniform surfaces and low roughness. Summary of the Invention

[0010] In response to the above problems, the present invention provides a method for preparing a polymer-based composite barrier film based on a deposition-heat treatment process. This method can manufacture polymer-based "enamel" and "glass-lined" at a lower temperature, which can greatly expand the selection range of polymers and glassy materials, thereby obtaining high-quality, high-performance composite films, thereby solving the problems of insufficient performance, high preparation cost and complex process of polymer-based deposition barrier films in the prior art.

[0011] In order to achieve the above object, the present invention provides a method for preparing a polymer substrate composite barrier film based on a deposition-heat treatment process, comprising the following steps:

[0012] Preparing a deposition layer: preparing a deposition layer on a polymer substrate by a vapor deposition method to obtain a deposition composite film; the polymer substrate is a self-supporting or independent flexible film, the deposition layer includes an inorganic layer, at least one inorganic layer is a fusible glass layer, and the inorganic layer has deposition defects; the vapor deposition method includes physical vapor deposition or chemical vapor deposition;

[0013] Heat treatment: The deposited composite film is heat treated to make the temperature of the fusible glass layer ≥ the sealing temperature of the fusible glass, so that the fusible glass melts and fills the deposited defects; the temperature is lowered to room temperature to solidify the fusible glass under stress relaxation conditions; the heat treatment includes heating or laser irradiation; during the heat treatment, the temperature of the polymer substrate is lower than its maximum heat resistance temperature.

[0014] The deposited layer prepared by vapor deposition has deposition defects and high permeability (water vapor permeability is usually greater than 10 -2 gm -2 day -1 ), and in the above-mentioned heat treatment step, the mobility of the atoms constituting the fusible glass layer is enhanced under the condition of being higher than its sealing temperature. At high temperature, its constituent atoms undergo thermal motion, self-leveling of the surface or filling of micro defects in the inorganic layer under the action of capillary force, eliminating the micro defects (voids) generated during the deposition process, improving its density and uniformity, making the composite film have higher barrier capacity and lower permeability, and the structural transformation is as follows: Figures 1 to 2 or Figure 3 . After heat treatment, the composite film needs to be cooled to room temperature so that the fusible glass can be cooled and formed in a state of stress relaxation to avoid warping and deformation caused by thermal stress. The above preparation method combines the deposition method (PVD / CVD) with the fusible glass material, and uses the deposition method and heat treatment process to develop a new method for preparing high-performance barrier films. This method greatly reduces the requirements of the organic polymer substrate "enamel" and "glass enamel" for the heat resistance of the polymer; at the same time, the technology cleverly utilizes the atomic thermal motion and melt self-leveling characteristics of the fusible glass when heated. By setting up a heat treatment process, the fusible glass layer fills the gaps remaining in the deposition layer, and then transforms into a coherent and defect-free layer structure, effectively solving the problem of residual defects when preparing barrier films using the existing PVD / CVD method. The preparation method is simple in process and suitable for scale-up to roll-to-roll continuous production. It has high manufacturing efficiency and low cost, and is very conducive to large-scale industrial applications.

[0015] In one embodiment, the heat-resistant temperature of the polymer substrate is ≥250°C.

[0016] In one embodiment, the preparation method further includes providing a modified layer in the polymer substrate composite barrier film, wherein the modified layer includes one or more layers; the modified layer is used to improve the wetting and spreading ability of the fusible glass melt on the polymer substrate, improve the adhesion of the glass layer to the polymer substrate, prevent or slow down the corrosion of the fusible glass melt on the polymer substrate at high temperature and / or isolate the damage of the high temperature of the fusible glass melt to the polymer substrate.

[0017] In the present invention, the composite film may not be provided with a modified layer, or one or more modified layers may be provided between the deposited layer (containing the fusible glass layer) and the polymer substrate in order to further improve the bonding between the two. The modified layer can improve the ability of the molten glass to wet and spread on the substrate, enhance the interaction between the glass layer and the substrate, prevent or slow down the corrosion of the substrate by the molten glass at high temperatures, and isolate the damage of the high temperature of the molten glass to the polymer. By providing the modified layer, the wettability of the molten glass to the polymer substrate is improved, the bonding force of the glass layer to the polymer substrate is improved, the corrosion resistance of the polymer is improved, the thermal insulation is increased, and the damage to the polymer caused by temperature is reduced. Since vapor deposition can be performed in multiple rounds, the modified layer can be located between the polymer substrate and the deposited layer, or in the deposited layer of the multi-layer structure, or both, as needed.

[0018] In one embodiment, in the step of providing the modified layer, the vapor deposition method includes physical vapor deposition or chemical vapor deposition.

[0019] In one embodiment, the material of the modified layer includes at least one of metal, metal oxide, metal nitride, and metal oxynitride.

[0020] In one embodiment, the method for preparing the polymer substrate includes the following steps: stretching a polymer film, and performing surface activation treatment on the polymer film to obtain a polymer substrate; the surface activation treatment includes: at least one of corona treatment, plasma treatment, and alkali activation.

[0021] In one embodiment, the polymer substrate is mainly prepared from a heat-resistant polymer, and the heat-resistant polymer includes at least one of polyimide (PI), polybenzoxazole (PBO), polybenzimidazole (PBI), polybenzothiazole (PBT), polyoxadiazole (POXA), polyquinazolinedione (PQZO), polyquinoxaline (PQ), polyphenylquinoxaline (PPQ), polyetheretherketone (PEEK), polyethylene naphthalate (PEN), and polyarylate (PAR).

[0022] The heat-resistant temperature of the polymer substrate is higher than the temperature of subsequent deposition of modified layers, inorganic layers, and fusible glass layers, or the heat-resistant temperature of the polymer substrate is higher than the actual temperature of the film position during heat treatment to ensure that the high-temperature process will not damage it.

[0023] In one embodiment, the physical vapor deposition in the step of preparing the deposited layer includes at least one of electron beam evaporation, ion beam sputtering, magnetron sputtering, and pulsed laser deposition;

[0024] The chemical vapor deposition in the step of preparing the deposited layer includes at least one of thermal chemical vapor deposition and plasma enhanced chemical vapor deposition;

[0025] The heat treatment is overall heating or laser heating;

[0026] When the heat treatment is laser heating, the laser irradiates the side of the deposited composite film having the fusible glass layer; the laser for the laser heating is a continuous laser or a pulsed laser, and the wavelength of the laser covers the spectrum range from ultraviolet light to infrared light.

[0027] Because atomic layer deposition itself can form a defect-free coverage and achieve a high barrier effect, there is no need to use fusible glass to fill the gaps to enhance the high barrier effect. This is expensive and has low manufacturing efficiency. The original intention of the research and development of this case was to improve the problem that ordinary deposition technology is difficult to prepare high-performance barrier films. Therefore, in the combined process of vapor deposition and heat treatment in this case, chemical vapor deposition does not take atomic layer deposition as a prerequisite.

[0028] The above-mentioned heat treatment temperature for glass is generally not less than 300°C. When the composite film is placed in a high-temperature field for heating, the heating temperature and time must be strictly controlled to prevent the polymer substrate from being damaged by long-term high-temperature heating. When laser heating is used, the laser energy should be mainly concentrated in the fusible glass layer, and the action time is generally very short. The heat decays rapidly during the transfer to the interior of the substrate. When the heat reaches the polymer substrate, the temperature is lower than the heat resistance temperature of the polymer, and the composite film can be manufactured. Laser heating can use continuous laser or pulsed laser, and the wavelength range covers ultraviolet light, visible light, and infrared light. The laser power density, scanning speed, spot size and other parameters need to be optimized according to the material properties and thickness of the fusible glass layer to ensure sufficient melting and avoid introducing new defects.

[0029] In one embodiment, the fusible glass is amorphous glass, and the sealing temperature of the fusible glass is ≤600°C, and the sealing temperature corresponds to a glass viscosity of 10 5 Temperature at Pa s;

[0030] The temperature of the heat treatment is ≥300°C.

[0031] Although fusible glass is nominally "melting", amorphous glass materials do not have a fixed melting point. Similar to organic polymers, they have a "melting limit". There are also references that use a specific viscosity (10 1 The temperature at which the glass melts is defined as the melting point. For the present invention, the focus is not just on the properties of a certain characteristic temperature point, but on the viscosity transition properties of the glass over the entire preparation temperature range. In order to be closer to what the applicant wants to express, a concept describing this behavior is used here: "viscosity transition temperature (T tr )". It refers to the temperature corresponding to the transition of any characteristic viscosity in the entire temperature range. It may be the temperature corresponding to any transition of deformation, sintering, firing, melting. For example, after the flux is introduced into silicate glass, the annealing point of the glass (10 12 Pa s), softening point (10 6.6 Pa s), working point (10 3 Pa s) temperatures have all decreased. These key transition temperatures are all related to viscosity and follow a consistent pattern of change. Therefore, in this case, the addition of flux lowers the viscosity transition temperature of the glass. This includes lowering the temperatures corresponding to the annealing point, softening point, and working point. The firing and flow properties of glass are closely related to its viscosity, requiring a low viscosity transition temperature. In other words, ideal fusible glass should have a viscosity transition temperature shifted toward lower temperatures compared to conventional glass.

[0032] The melting temperature of the amorphous fusible glass is low (<800°C), and the temperature at which the viscosity of the glass changes when heated is low. As an amorphous material, fusible glass itself is non-crystalline and does not crystallize during the heating and cooling process. It has no melting point but only a melting limit, and softens by changing its viscosity when heated. In the present invention, the sealing temperature of the fusible glass used is lower than 600°C. When heated to a temperature above the sealing temperature, the viscosity of the glass is less than 10 5 Pa s, it begins to show liquid fluidity, and the incoherent structures can be connected to each other to play a sealing role.

[0033] The present invention also provides a composite film based on vapor deposition-heat treatment obtained by the preparation method, wherein the thickness of the fusible glass layer is 0.01-500 μm; the fusible glass layer is arranged on one side or both sides of the polymer substrate.

[0034] The above-mentioned composite film is a deposited layer formed by vapor deposition, in which the fusible glass layer forms a relatively uniform coverage on the polymer substrate; the fusible glass layer undergoes thermal movement under the high temperature of heat treatment, filling the void defects remaining in the deposition, thereby providing the densification degree of the inorganic layer and improving the barrier performance, so that the finally prepared composite film has ultra-high barrier performance and can be widely used in flexible electronic device packaging, display screen packaging, high-end food and drug packaging and other fields as an efficient barrier film, packaging film or protective film.

[0035] In one embodiment, the material of the fusible glass layer includes at least one of silicate glass, borate glass, bismuth glass, vanadate glass, tellurite glass, and phosphate glass.

[0036] The components of the fusible glass can be designed as needed. By adjusting the types and ratios of the components, the thermal, optical, electrical and chemical properties of the fusible glass layer can be optimized.

[0037] The present invention also provides a film comprising the polymer substrate composite barrier film based on deposition-heat treatment.

[0038] The present invention also provides use of the polymer-based composite barrier film or the film in a barrier film, a packaging film or a protective film.

[0039] In one embodiment, the polymer substrate composite barrier film includes at least one polymer substrate; and the deposited layer is directly or indirectly attached to one side or both sides of the polymer substrate.

[0040] The fusible glass layer in the coating can be applied to one or both sides of the polymer film. When applied to one side, it provides a barrier effect; when applied to both sides, it creates a redundant design, increasing the reliability of the composite film's barrier capabilities. This composite film can be widely used in flexible electronic device packaging, display packaging, high-end food and pharmaceutical packaging, and other fields as a highly effective barrier film, encapsulation film, or protective film.

[0041] In one embodiment, the polymer substrate has a thickness of 1-500 μm.

[0042] In one embodiment, the thickness of the fusible glass layer is 0.01-500 μm.

[0043] The thickness of the fusible glass layer is such that if it is too thin, it is difficult to form a continuous and dense barrier layer, while if it is too thick, it becomes rigid and is not conducive to roll-to-roll preparation.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The present invention discloses a polymer-based composite barrier film based on deposition-heat treatment, a method, and an application thereof. The method combines a deposition method (PVD / CVD) with a fusible glass material. Utilizing the deposition method and heat treatment process, a new method for preparing high-performance barrier films is developed. This method significantly reduces the heat resistance requirements of the polymers used in organic polymer-based "enamel" and "glass-lined" films. Furthermore, the technology cleverly utilizes the ability of fusible glass to flow at relatively low temperatures, namely, the atomic thermal motion and self-leveling properties of the melt when heated. By providing a heat treatment process, the fusible glass fills the remaining gaps in the deposited layer, thereby transforming the deposited layer into a coherent, defect-free, or low-defect layer structure. This effectively solves the problem of residual defects in barrier films prepared by existing PVD / CVD methods, and can obtain a high-density, highly uniform, and fully gap-filled inorganic layer at a relatively low temperature. This reduces the stringent requirements for deposition preparation and deposition conditions in the manufacture of ultra-high barrier films, addresses the problems of insufficient performance, high preparation cost, and complex process of polymer-based deposited barrier films in the prior art, and simplifies the manufacturing process of ultra-high barrier films, reducing manufacturing costs. This preparation method is simple and suitable for scale-up to roll-to-roll continuous production. Its high efficiency and low cost make it highly suitable for large-scale industrial applications, and it is highly competitive with extrusion coating methods. Furthermore, this method can produce highly heat-resistant composite films, enabling the use of molten glass for side seals, resulting in superior sealing performance compared to barrier films produced using conventional polymer deposition methods.

[0046] The polymer-based composite barrier film based on deposition-heat treatment has high barrier properties and can be widely used in flexible electronic device packaging, display packaging, high-end food and drug packaging and other fields as an efficient barrier film, packaging film or protective film. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 Schematic diagram of the polymer-based composite barrier film of the present invention before structural transformation during the preparation process;

[0048] Figure 2 Schematic diagram of the polymer-based composite barrier film of the present invention after structural transformation during the preparation process;

[0049] Figure 3 This is a schematic diagram of the polymer-based composite barrier film of the present invention after structural transformation during the preparation process. DETAILED DESCRIPTION

[0050] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the accompanying drawings. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0052] Example 1

[0053] Polyimide (PI) based composite film

[0054] (1) Substrate preparation

[0055] Upilex-S polyimide film, 25 μm thick and heat-resistant to temperatures exceeding 550°C, was selected as the substrate. First, the PI film was secured to a roller using an automatic tensioning device to ensure a smooth, wrinkle-free surface. The PI film surface was then activated using oxygen plasma treatment to increase its surface energy and compatibility. The plasma treatment was performed in a vacuum chamber with an RF power of 200 W, an oxygen flow rate of 20 sccm, and a treatment time of 60 seconds. The water contact angle of the treated PI film surface was reduced from 85° to below 30°.

[0056] (2) Modified layer deposition

[0057] An AlN modified layer was deposited on the surface of the activated PI film using radio frequency magnetron sputtering to improve adhesion of the subsequent glass layer to the PI substrate. The AlN sputtering target had a purity of 99.99%. The sputtering atmosphere consisted of a mixture of Ar and N₂, with a 20% N₂ volume fraction and a total pressure of 0.5 Pa. The RF power was set at 150 W, the substrate temperature at 200°C, and the deposition time was 30 minutes, resulting in an AlN modified layer approximately 50 nm thick.

[0058] (3) Deposition of fusible glass layer

[0059] A multi-target magnetron sputtering system was used to deposit a fusible glass layer composed of PbO-SiO2-Na2O-CaF2. The sputtering targets consisted of PbO, SiO2, Na2O, and CaF2 in an area ratio of 4:4:1:1. The sputtering atmosphere was pure Ar, with a total pressure of 1 Pa, an RF power of 200 W, and a substrate temperature of 250°C. A computer program controlled the on / off timing of each sputtering source to achieve in-situ regulation and uniform deposition of the glass components. The deposition time was 2 hours, resulting in a fusible glass layer approximately 2 μm thick with a composition of 40 PbO-40 SiO2-15 Na2O-5 CaF (mol%).

[0060] (4) Heat treatment

[0061] The PI-based composite film with the fusible glass layer deposited thereon is placed in a vacuum heat treatment furnace for overall heating. -1 The temperature was raised to 500℃ at a rate of 100℃ and kept at this temperature for 10min to make the fusible glass layer fully melted and achieve self-smoothing surface; then the temperature was raised to 500℃ at a rate of 2℃min -1 The temperature is lowered to room temperature at a rate of 100°C, allowing the fusible glass to solidify under stress relaxation conditions, resulting in a flat and smooth glass layer surface. During the heat treatment, pure N2 is introduced as a protective atmosphere with a flow rate of 200 sccm and the furnace chamber pressure is maintained at around 100 Pa.

[0062] (5) Performance characterization

[0063] The properties of the prepared PI-based fusible glass composite film were characterized. Surface roughness was measured using atomic force microscopy, and the Ra value was less than 5nm. Energy dispersive spectrometer analysis of the glass layer revealed uniform distribution of elements, essentially consistent with the designed composition.

[0064] The water vapor transmission rate of the composite film was tested according to GB / T 21529-2008. At 38℃ / 85%RH, the WVTR value was 5×10 -3 gm -2 day -1 The oxygen transmission rate of the composite film was tested by isobaric method according to GB / T 19789-2005. Under the conditions of 23℃ / 50%RH, the OTR value was 8×10-1 cm 3 m -2 day -1 The test conditions in the following examples are the same as in this example.

[0065] Example 2

[0066] Polyetheretherketone (PEEK)-based composite membrane

[0067] (1) Substrate preparation

[0068] A 50μm thick PEEK film was selected as the substrate. Its glass transition temperature is 143°C and its melting temperature is 343°C. It can be used for a long time at temperatures above 250°C without performance degradation. The PEEK film was fixed on a roller and the surface was modified by corona treatment. The corona treatment was carried out in an atmospheric environment with an electrode voltage of 10kV, an electrode spacing of 2mm, and a treatment speed of 5m / min. -1 After three round trips, the surface tension of the PEEK film was reduced from 32 mN m -1 Increased to 58 mN m -1 .

[0069] (2) Modified layer deposition

[0070] Electron beam evaporation was used to deposit a double-layer modified SiO2 / Al2O3 layer on a PEEK substrate to improve the wetting and spreading properties of the subsequent glass layer. The purity of the SiO2 and Al2O3 particles used for evaporation was 99.99%. The SiO2 layer was first deposited with an evaporation power of 500W and a deposition rate of The substrate temperature is 100℃, and a SiO2 layer with a thickness of about 20nm is obtained. Then the Al2O3 layer is deposited with an evaporation power of 800W and a deposition rate of The substrate temperature was 150°C, and an Al2O3 layer with a thickness of about 30 nm was obtained.

[0071] (3) Deposition of fusible glass layer

[0072] A fusible glass layer composed of Bi2O3-B2O3-ZnO-AlN was deposited by co-evaporation using a multi-source electron beam evaporation system. The evaporation source materials were Bi2O3, B2O3, ZnO, and AlN particles, all with a purity exceeding 99.9%. The power of each evaporation source was 800W, 500W, 300W, and 200W, respectively. The substrate temperature was 200°C, and the evaporation chamber vacuum was better than 1×10 -3 Pa. The evaporation rate of each component was monitored by a quartz crystal oscillator, and the power of each source was dynamically adjusted to ensure that the glass layer composition was 50Bi2O3-30B2O3-15ZnO-5AlN (wt.%). The evaporation time was 30 minutes, resulting in a fusible glass layer with a thickness of approximately 1.5 μm.

[0073] (4) Heat treatment

[0074] The fusible glass layer is heat treated by laser selective heating method. The laser wavelength is 266nm and the power density is 50Wcm -2 , spot diameter is 5 mm, scanning speed is 10 mm s -1 , repeat the scan 10 times to cover the entire glass layer surface. Under laser irradiation, the glass layer melts and flows and is fully self-smoothed, and the surface roughness Ra is reduced to below 2nm. Laser heat treatment is carried out in N2 protective atmosphere with an N2 flow rate of 10L min -1 During the heating process, the temperature of the PEEK substrate is always below 200° C. The composite film after heat treatment is cooled to obtain a polymer substrate composite film containing a fusible glass layer.

[0075] (5) Performance characterization

[0076] The water vapor barrier property of the composite film was tested. At 85℃ / 85%RH, its WVTR value was 1×10 -3 gm -2 day -1 The oxygen barrier property of the composite film was tested. Under the conditions of 23℃ / 0%RH, its OTR value was 5×10 -1 cm 3 m -2 day -1 .

[0077] Example 3

[0078] Polyarylate (PAR)-based composite membrane

[0079] (1) Substrate preparation

[0080] A PAR film with a thickness of 75 μm was selected as the substrate. Its glass transition temperature is 230°C and the continuous use temperature can reach 280°C. The PAR film was fixed on a roller and the surface was activated by alkali treatment. The film was immersed in 2 mol L -1 The PAR substrate was immersed in KOH solution for 3 min, then washed repeatedly with deionized water, and dried to obtain a PAR substrate with a rough surface and enhanced hydrophilicity.

[0081] (2) Modified layer deposition

[0082] Pulsed laser deposition (PLD) was used to deposit an AlON modified layer on a PAR substrate to improve adhesion between the glass layer and the substrate and to prevent heat transfer from the glass layer to the substrate. PLD used a KrF excimer laser with a wavelength of 248 nm, a pulse width of 20 ns, a frequency of 10 Hz, and a pulse energy of 200 mJ. The target material was a mixture of high-purity AlN and Al2O3 with an atomic ratio of 1:1. The substrate temperature was 300°C and the oxygen partial pressure was 5 × 10 -3 Pa, the deposition time was 15 min, and an AlON layer with a thickness of about 80 nm was obtained.

[0083] (3) Deposition of fusible glass layer

[0084] A fusible glass layer composed of V2O5-TeO2-BaO-ZnS was prepared using pulsed laser deposition (PLD). The laser parameters were the same as those used for the AlON modified layer deposition. The target material was a sintered mixture of V2O5, TeO2, BaO, and ZnS in a molar ratio of 50:20:20:10. The substrate temperature was 250°C and the oxygen partial pressure was 1×10 -2 Pa, and a deposition time of 1 hour, a fusible glass layer with a thickness of about 1 μm was obtained. The introduction of oxygen during the PLD process can compensate for oxygen vacancies in the glass, improving the density and transparency of the glass layer.

[0085] (4) Heat treatment

[0086] Based on the heat resistance limit of PAR substrate (<280℃), the deposited fusible glass layer was treated by laser heating. A 355nm Nd:YAG pulsed laser was used to irradiate the surface of the PAR composite film, and the parameters were set to 0.2-0.6J cm -2 Energy density, 20-100Hz pulse frequency. By precisely controlling the scanning path and speed (5-20mm s -1 ) to ensure that the spot evenly covers the entire surface. The laser energy is rapidly absorbed by the glass layer, causing it to quickly heat up to above the sealing temperature, quickly melting and filling microscopic defects to form a continuous and dense inorganic barrier layer. Due to the short laser action time and the energy concentration on the surface, heat penetration into the substrate is limited, and the substrate temperature rise is controlled to be well below 280°C to avoid thermal degradation and deformation. The entire process is carried out under the protection of an inert atmosphere to prevent high-temperature oxidation. The heat-treated composite film is cooled to obtain a polymer-based composite film containing a fusible glass layer.

[0087] (5) Performance characterization

[0088] The bonding strength between the glass layer and the PAR substrate was tested by the pull-out method, and the interface bonding strength between the two was found to be 15 MPa, which was significantly higher than that of the sample without AlON modification. The oxygen barrier property of the composite film was tested, and its OTR value was 2×10 -1cm 3 m -2 day -1 The water vapor barrier property of the composite film was tested. At 38℃ / 85%RH, its WVTR value was 3×10 -3 gm -2 day -1 .

[0089] Example 4

[0090] Polyethylene naphthalate (PEN) based composite film.

[0091] (1) Substrate preparation

[0092] A 100μm thick PEN film was selected as the substrate. Its glass transition temperature is 120°C and its melting point is 270°C. It can be used for a long time below 200°C. The PEN film was subjected to a double surface activation treatment: first, the film surface was treated with oxygen plasma using a 13.56MHz, 200W radio frequency glow discharge for 2 minutes, and then the film surface was treated with UV-ozone using a 185nm / 254nm dual-wavelength UV lamp for 5 minutes. After the above treatment, the surface tension of the PEN film can be increased to 70mN m -1 above.

[0093] (2) Modified layer deposition

[0094] A metallic Mo film was deposited on the surface of the activated PEN film using magnetron sputtering to strengthen the bonding between the glass layer and the substrate. The Mo sputtering target had a purity of 99.95%, the sputtering atmosphere was pure Ar, the pressure was 1 Pa, the sputtering power was 100 W, the substrate temperature was 50°C, and the sputtering time was 30 seconds. A Mo film with a thickness of approximately 10 nm was obtained. The Mo layer, acting as a transition layer, forms a stable Mo-O-C covalent bond with the PEN at high temperatures, significantly improving the bonding strength.

[0095] (3) Deposition of fusible glass layer

[0096] A multi-target magnetron sputtering method was used to deposit a fusible glass layer composed of P2O5-Li2O-BaO-AlF3. The sputtering targets used were P2O5, Li2O, BaO, and AlF3, all with purities exceeding 99.9%, and a target area ratio of 5:3:1:1. The sputtering atmosphere was a mixture of Ar and O2, with a total pressure of 0.5 Pa and a flow ratio of Ar to O2 of 4:1. A sputtering power of 200 W, a substrate temperature of 180°C, and a sputtering time of 90 minutes produced a fusible glass layer approximately 1.2 μm thick with a refractive index of 1.55, close to that of PEN (1.50). The introduction of O2 helps compensate for oxygen vacancies in the glass layer, reducing dispersion and improving transparency.

[0097] (4) Heat treatment

[0098] The PEN composite film with a fusible glass layer was treated by laser heating. A 355 nm continuous wave laser was used, focused on the glass layer surface, with a power density of 30 W cm -2 The spot diameter is 5mm. The laser is controlled by the scanning galvanometer at a speed of 10mms -1 The laser scans at a uniform speed, repeated 3-5 times to ensure sufficient heating. The laser energy is absorbed by the glass layer, rapidly raising its temperature above the sealing temperature, achieving melting, flow, and self-smoothing. The laser action time is extremely short, and the energy is concentrated on the surface, resulting in limited heat transfer to the PEN substrate. Precisely controlled parameters ensure that the PEN substrate temperature remains below 180°C to avoid thermal damage. The entire process is carried out in a nitrogen atmosphere to prevent high-temperature oxidation or degradation. Upon completion, the film is naturally cooled to room temperature, resulting in a polymer-based composite film containing a fusible glass layer.

[0099] (5) Performance characterization

[0100] The oxygen barrier property of the composite film was tested. At 23℃ / 0%RH, its OTR value was 5×10 -2 cm 3 m -2 day -1 The water vapor barrier property of the composite film was tested. At 38℃ / 85%RH, its WVTR value was 8×10 -3 gm -2 day -1 .

[0101] Example 5

[0102] Polybenzimidazole (PBI) based composite membrane.

[0103] (1) Substrate preparation

[0104] A 50μm-thick PBI film was selected as the substrate. Its glass transition temperature reaches 450°C, allowing for long-term use below 400°C. The PBI film was mounted on a roller and subjected to a surface hydroxylation treatment using plasma spraying. Using Ar as the carrier gas and water vapor as the reactant, the treatment was conducted for 5 minutes at an RF power of 150W, a pressure of 1kPa, and a substrate temperature of 80°C. This introduced a large number of hydrophilic hydroxyl groups onto the PBI surface, reducing the water contact angle from 85° to below 30°.

[0105] (2) Gradient modified layer deposition

[0106] A Ti-SiO2 gradient transition layer was prepared on a PBI substrate using a composite method of electron beam evaporation and plasma-enhanced chemical vapor deposition (PECVD) to mitigate the thermal expansion coefficient mismatch between the glass layer and the PBI substrate. The composite source consisted of metallic Ti particles and SiO2 particles with a Ti:Si atomic ratio of 1:1. Ti and SiO2 were first evaporated using an electron beam at 500W and 800W, respectively, and an oxygen partial pressure of 5×10 -3 Pa, the substrate temperature was set at 250°C, and evaporation was carried out for 10 minutes to form a gradient layer with a continuous transition from Ti to SiO2 on the PBI surface. Then, under the same conditions, a TEOS and O2 mixed gas was introduced, and a layer of SiO2 was deposited on the gradient layer using PECVD to a thickness of approximately 50nm, ultimately obtaining a Ti-SiO2 gradient modified layer with a thickness of approximately 100nm.

[0107] (3) Deposition of fusible glass layer

[0108] A multi-source electron beam evaporation method was used to deposit a fusible glass layer composed of B2O3-SiO2-K2O-Na2SO4. The evaporation source materials were B2O3, SiO2, K2CO3, and Na2SO4, all with purities exceeding 99.99%. The evaporation power of each source was 600W, 1000W, 300W, and 200W, respectively. The substrate temperature was 300°C, and the background vacuum was better than 5×10 -4 After evaporation for 1 h, a fusible glass layer with a thickness of about 2.5 μm was obtained, whose composition was 60B2O3-25SiO2-10K2O-5Na2SO4 (mol%).

[0109] (4) Heat treatment

[0110] The PBI composite film with the fusible glass layer deposited was placed in a tube furnace and heated at 10 °C min -1 The temperature was raised to 450℃ at a rate of 10min, kept at that temperature for 10min, and then heated at 5℃min -1 The rate of heat treatment is reduced to room temperature, allowing the fusible glass to solidify under stress-relaxed conditions. Heat treatment is performed in a pure Ar atmosphere with an Ar flow rate of 200 sccm. After long, high-temperature heat treatment, the stress in the glass layer is fully released, further stabilizing the amorphous structure. Simultaneously, at high temperatures, a bond is formed at the interface between the glass layer and the PBI substrate, significantly enhancing the bonding strength between the two.

[0111] (5) Performance characterization

[0112] The oxygen barrier property of the composite film was tested. At 23℃ / 0%RH, its OTR value was 6×10 -1 cm 3 m -2 day -1The water vapor barrier property of the composite film was tested. At 38℃ / 85%RH, its WVTR value was 1×10 -3 gm -2 day -1 .

[0113] Example 6

[0114] Polyimide (PI) based composite film.

[0115] (1) Substrate preparation

[0116] A 125μm-thick polyimide (PI) film is used as the substrate. It has excellent heat resistance, with a glass transition temperature exceeding 350°C, making it suitable for high-temperature processing in subsequent processes. Oxygen plasma treatment is used to activate the PI film surface, improving its surface energy and enhancing the adhesion of subsequent coatings. For example, this can be performed in a vacuum chamber with an RF power of 150W, an oxygen flow rate of 30sccm, and a treatment time of 90s.

[0117] (2) Preparation of intermediate layer by sol-gel method

[0118] 100 mL of deionized water was added to a three-necked flask and heated to 85°C. 1 g of aluminum isopropoxide was crushed into a powder and added to the water, stirring for 2 hours. The aluminum isopropoxide gradually hydrolyzed, and the system became a white, turbid liquid. 0.35 g of concentrated HNO3 (65 wt.%) was added to acidify the solution, and the mixture was stirred under reflux and water-cooled for 10-15 hours to obtain a clear sol. The sol was coated on a surface-activated polyimide film, dried at 80°C for 2 hours to gelate it, and then heated to 350°C to form an aluminum oxide interlayer. This temperature is below the decomposition temperature of polyimide (PI), ensuring the integrity of the substrate.

[0119] (3) Deposition of fusible glass layer

[0120] A fusible glass layer of TeO2-ZnO-Nb2O5-Na3N composition was deposited on the intermediate layer using a multi-target radio frequency magnetron sputtering method. TeO2, ZnO, Nb2O5 ceramic targets and a metal sodium target were used. The sputtering atmosphere was a mixture of Ar and N2, with a total pressure controlled at 0.5 Pa. The N2 partial pressure was precisely regulated to control the amount of nitrogen incorporated. By independently adjusting the sputtering power of each target, precise control of the stoichiometric ratio of the glass layer was achieved, with the target composition being approximately 50TeO2-20ZnO-25Nb2O5-5Na3N (mol%). The substrate temperature was maintained at 200°C, and the deposition time was approximately 50 minutes, resulting in a fusible glass film with a thickness of approximately 180 nm. The film deposited by this method has deposition defects, which are suitable for repair and densification in subsequent heat treatment steps.

[0121] (4) Heat treatment

[0122] Laser rapid thermal treatment of PI composite film deposited with fusible glass layer was performed using an excimer laser with a wavelength of 308nm and a pulse energy density of 0.5Jcm -2 , pulse frequency is 50Hz, spot size is 3×3mm, scanning speed is 10mms -1 , scan 20 times as needed, and scan to cover the entire surface of the glass layer. Laser annealing can make the glass layer reach an extremely high instantaneous temperature (>600°C) in a very short time (nanosecond level), causing rapid melting and solidification, thereby obtaining a dense, uniform, and smooth glass layer. At the same time, due to the extremely short heating time, the heat transferred to the PI substrate is limited, and the substrate temperature is far below its thermal damage threshold, so the PI will not suffer obvious thermal damage. The entire process is carried out under the protection of an inert atmosphere such as nitrogen. The composite film that has undergone laser heat treatment is cooled, and finally a PI-based composite film containing a densified fusible glass layer is obtained.

[0123] (5) Performance characterization

[0124] The performance of the prepared PI-based fusible glass composite film was tested. Atomic force microscopy (AFM) was used to characterize the surface morphology of the composite film. The surface roughness Ra was less than 1 nm, showing a typical molten morphology. The barrier properties of the composite film were tested. At 38°C / 85% RH, the WVTR value was 1×10 -3 gm -2 day -1 .

[0125] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0126] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A method for preparing a polymer substrate composite barrier film based on a deposition-heat treatment process, characterized in that: The following steps are involved: Preparing a deposition layer: preparing a deposition layer on a polymer substrate by a vapor deposition method to obtain a deposition composite film; the polymer substrate is a self-supporting or independent flexible film, the deposition layer includes an inorganic layer, at least one inorganic layer is a fusible glass layer, and the inorganic layer has deposition defects; the vapor deposition method includes physical vapor deposition or chemical vapor deposition; Heat treatment: The deposited composite film is heat treated to make the temperature of the fusible glass layer ≥ the sealing temperature of the fusible glass, so that the fusible glass melts and fills the deposited defects; the temperature is lowered to room temperature to solidify the fusible glass under stress relaxation conditions; the heat treatment includes heating or laser irradiation; during the heat treatment, the temperature of the polymer substrate is lower than its maximum heat resistance temperature.

2. The method according to claim 1, characterized in that The preparation method also includes providing a modified layer in the polymer substrate composite barrier film, wherein the modified layer includes one or more layers; the modified layer is used to improve the ability of the fusible glass melt to infiltrate and spread on the polymer substrate, improve the adhesion of the glass layer to the polymer substrate, prevent or slow down the corrosion of the fusible glass melt on the polymer substrate at high temperature, and / or isolate the polymer substrate from damage caused by the high temperature of the fusible glass melt.

3. The method according to claim 2, characterized in that The material of the modified layer includes at least one of metal, metal oxide, metal nitride and metal oxynitride.

4. The method according to any one of claims 1 to 3, characterized in that The preparation method of the polymer substrate comprises the following steps: tensioning a polymer film and performing surface activation treatment on the polymer film to obtain a polymer substrate; the surface activation treatment comprises at least one of corona treatment, plasma treatment, and alkali activation.

5. The method according to claim 4, characterized in that The physical vapor deposition in the step of preparing the deposited layer includes at least one of electron beam evaporation, ion beam sputtering, magnetron sputtering, and pulsed laser deposition; The chemical vapor deposition in the step of preparing the deposited layer includes at least one of thermal chemical vapor deposition and plasma enhanced chemical vapor deposition; The heat treatment is overall heating or laser heating; When the heat treatment is laser heating, the laser irradiates the side of the deposited composite film having the fusible glass layer; the laser for the laser heating is a continuous laser or a pulsed laser, and the wavelength of the laser covers the spectrum range from ultraviolet light to infrared light.

6. The method according to claim 4, characterized in that The fusible glass is amorphous glass, and the sealing temperature of the fusible glass is ≤600°C, and the sealing temperature corresponds to a glass viscosity of 10 5 Temperature at Pa s; The temperature of the heat treatment is ≥300°C.

7. The polymer substrate composite barrier film based on deposition-heat treatment obtained by the preparation method according to any one of claims 1 to 6, characterized in that: The thickness of the fusible glass layer is 0.01-500 μm; the fusible glass layer is arranged on one side or both sides of the polymer substrate.

8. The polymer substrate composite barrier film based on deposition-heat treatment according to claim 7, characterized in that: The material of the fusible glass layer includes at least one of silicate glass, borate glass, bismuth glass, vanadate glass, tellurite glass, and phosphate glass.

9. A film, characterized in that A polymer substrate composite barrier film based on deposition-heat treatment according to any one of claims 7 to 8.

10. Use of the polymer-based composite barrier film according to any one of claims 7 to 8 or the film according to claim 9 in a barrier film, packaging film or protective film.

Images