EP3887901A1

EP3887901A1 - Method for manufacturing an electrochromic glazing

Info

Publication number: EP3887901A1
Application number: EP19868187.6A
Authority: EP
Inventors: Pascal Reutler
Original assignee: Saint Gobain Glass France SAS; Compagnie de Saint Gobain SA
Current assignee: Saint Gobain Glass France SAS; Compagnie de Saint Gobain SA
Priority date: 2018-11-28
Filing date: 2019-11-27
Publication date: 2021-10-06
Also published as: FR3088850A1; US20220009825A1; WO2020109725A1; CN113039483A; FR3088850B1; JP2022509782A

Abstract

The present invention relates to a method for manufacturing an electrochromic glazing, said glazing having an electrochromic stack comprising: a first transparent conductive layer (TCO1), a layer of an electrochromic material (EC), a layer of an ionic conductive electrolyte (CI), a counter electrode layer (CE), a second transparent conductive layer (TCO2), said method comprising the following steps: providing a first glass panel (2) and a second glass panel (2); depositing a first transparent conductive layer (TCO1) on the first glass panel and a second transparent conductive layer (TCO2) on the second glass panel; depositing a layer of a material (EC) on the first transparent conductive layer (TCO1) and a counter electrode layer (CE) on the second transparent conductive layer (TCO2); depositing the layer of an ionic conductive electrolyte (CI) on either of the layers of an electrochromic material (EC) or counter electrode (CE); assembling the two glass panels to form a laminated glazing. The invention is characterized in that it further comprises at least one heat treatment step consisting in thermally treating at least one transparent conductive layer (TCO1, TCO2) of a glass panel by a rapid thermal treatment device before assembling the glass panels.

Description

DESCRIPTION

Title: PROCESS FOR THE MANUFACTURE OF AN ELECTROCHROME WINDOW

The present invention relates to the field of electrochromic glazing and to its manufacturing process.

PRIOR ART

Electrochromic devices and in particular electrochromic glazing comprise in known manner an electrochromic stack comprising a succession of five layers essential for the operation of the device, that is to say the reversible color change following the application of an electrical supply. appropriate. These five functional layers are:

-A first transparent electroconductive layer,

-A layer of an electrochromic material, capable of reversibly and simultaneously inserting ions, the oxidation states of which correspond to the inserted and de-inserted states are of a distinct color when they are subjected to an appropriate electrical supply; one of these states having a higher light transmission than the other,

-A layer of an electronic insulating electrolyte and ionic conductor,

-a counter-electrode layer, capable of reversibly inserting ions of the same charge as that which the electrochromic material can insert, and

-A second transparent electroconductive layer,

either of the transparent electrically conductive layers which may be in contact with the transparent substrate.

In the most widespread electrochromic systems, these five layers all consist of inorganic solid materials, most often metal oxides, and are deposited by sputtering magnetron on a glass substrate. They are commonly called "all solid" electrochromic systems.

The method of manufacturing by magnetron sputtering of such a mineral electrochromic system with at least five layers comprises one or more stages of heat treatment (annealing) during or after the steps of depositing the layers by magnetron sputtering. Some materials, in particular the metal oxides forming the two outermost transparent conductive layers of the stack, are deposited by magnetron sputtering. To have sufficient crystallinity and conductivity, these conductive layers can be deposited hot, or be deposited cold and undergo, after this cold deposit, a heat treatment. The performance and optical properties of the final product strongly depend on these heat treatment steps.

Another known method consists of providing two glass panels and depositing, on each of them, a transparent conductive layer (TC).

Subsequently according to this other method, the electrochromic layer (EC) and the counter-electrode layer (CE) are each deposited on a transparent conductive layer. Next, the layer of an electronically insulating and ionically conductive electrolyte is arranged on the electrochromic layer (EC) or on the counter-electrode layer (CE). The whole is then assembled to form the glazing. This assembly step further comprises the realization of the connection means for bringing the current to the transparent conductive layers.

If the transparent conductive layers are deposited cold, the roughness of the layers is low, which has an advantage, but their electrical conductivity is also low so that the performance is lower. However, if the layers are subjected to a heat treatment of the annealed type, this is characterized by a slow rise in temperature and by a high treatment time, usually about one hour in an oven at 400 ° C. , the electrical conductivity of the layers increases so as to improve the performance of the glazing. However, this treatment involves an increase in the size of the crystals and therefore also in the roughness. This increase in the size of the crystals is also observed if the transparent conductive layers are deposited hot (deposition at a temperature above 150 ° C.).

However, as each transparent conductive layer (TCO) is heat treated independently, the roughness of the transparent conductive layers is different. Thus, during the assembly of the glass panels, the assembly formed of the transparent conductive layer and the electrochromic layer (EC) on one side and the assembly formed of the transparent conductive layer and of the counter layer. electrode (CE) on the other side, with different roughness, exert pressure / stress on the electrolyte layer, electronic insulator and ionic conductor at the risk of deforming it. As this roughness is uneven, there may exist an uneven thickness locally, that is to say that locally the layer of an ion conducting electrolyte is more compressed, thin, thus rendering the performance of the electrochromic glazing uneven and inhomogeneous.

SUMMARY OF THE INVENTION

The present invention therefore proposes to resolve these drawbacks by providing a method for producing an electrochromic glazing in which the electrolyte layer has local variations of smaller thickness.

To this end, the invention relates to a method for manufacturing an electrochromic glazing, said glazing comprising an electrochromic stack comprising: a first transparent conductive layer,

-a layer of a mineral electrochromic material with cathodic coloring, called electrochromic electrode,

-a layer of an ion conductive electrolyte and electrical insulator,

-a counter electrode layer,

a second transparent conductive layer,

said method comprising the following steps:

- have a first glass panel and a second glass panel;

depositing a first transparent conductive layer on the first glass panel and a second transparent conductive layer on the second glass panel;

- depositing a layer of an electrochromic material on the first transparent conductive layer and a counter-electrode layer on the second transparent conductive layer;

- deposit a layer of an ion-conducting electrolyte on one or the other of the layers of electrochromic material and counter-electrode;

- assemble the two glass panels to form a laminated glazing, Characterized in that it further comprises at least one heat treatment step consisting in thermally treating at least one glass panel provided with at least one transparent conductive layer by a rapid heat treatment device before assembling the panels of glass.

According to an example, said heat treatment step is used to treat the transparent conductive layer of each glass panel.

In one example, a heat treatment step is also used to treat the layer of an electrochromic material and / or the counter-electrode layer.

According to an example, said step of heat treatment of said at least one transparent conductive layer is carried out after the deposition of the first transparent conductive layer on the first glass panel and / or of the second transparent conductive layer on the second glass panel.

According to an example, said heat treatment step is carried out to simultaneously treat the layer of an electrochromic material and the first transparent conductive layer and / or to simultaneously treat the counter-electrode layer and the second transparent conductive layer.

According to one example, the heat treatment device is placed opposite the layer to be treated and is arranged to bring the layer to be treated to a temperature at least equal to 300 ° C.

According to one example, the heat treatment device is arranged to heat treat the layer to be treated for a short time, preferably less than 100 milliseconds.

According to one example, the heat treatment device is a laser device emitting radiation having a wavelength between 300 and 2000 nm.

According to one example, the heat treatment device comprises at least one intense pulsed light lamp emitting radiation having an emission spectrum preferably comprising several lines, in particular at wavelengths ranging from 160 to 1000 nm, each pulse of light preferably having a duration in a range from 0.05 to 20 milliseconds.

DESCRIPTION OF THE FIGURES Other particularities and advantages will emerge clearly from the description given below, by way of indication and in no way limitative, with reference to the appended drawings, in which:

- fig. 1 is a schematic representation of the electrochromic glazing according to the invention;

DETAILED DESCRIPTION OF THE INVENTION

In Figure 1 is shown an electrochromic glazing 1. Such an electrochromic glazing comprises two glass panels 2 made integral by means of a frame or frame. Between these two glass panels, a complete electrochromic stack 3 is arranged. This stack includes:

-A first transparent electroconductive layer TC01,

-A layer of EC electrochromic material, capable of reversibly and simultaneously inserting ions, the oxidation states of which correspond to the inserted and de-inserted states are of a distinct color when they are subjected to an appropriate electrical supply ; one of these states having a higher light transmission than the other,

-A layer of an electronic insulating electrolyte and ionic conductor Cl,

-A CE counter-electrode layer, capable of reversibly inserting ions of the same charge as that which the electrochromic material can insert, and

-A second transparent electroconductive layer TC02.

The five layers (TC01 / EC / CI / CE / TC02) listed above are the only functional layers essential for the proper functioning of electrochromic glazing.

The electrochromic stack 3 can comprise other useful layers, which are however not essential for obtaining an electrochromic behavior. It can for example comprise, between the glass substrate and the adjacent TCO layer, a barrier layer, known to prevent for example the migration of sodium ions. The stack can also include one or more anti-reflection or color adaptation layers comprising for example an alternation of transparent layers with high index and low refractive index. All the mineral layers of the stack are preferably deposited by sputtering, reactive or not, assisted by magnetic field, generally in the same installation under vacuum.

The materials capable of serving as transparent conductive oxides for the two transparent conductive layers TCO are known. By way of example, mention may be made of indium oxide, mixed tin and indium oxide, tin oxide, doped tin oxide, zinc oxide, doped zinc oxide, ruthenium oxide, doped ruthenium oxide and zinc oxide doped with aluminum and / or gallium. Preferably, mixed tin and indium oxide (ITO) or zinc oxide doped with aluminum and / or gallium will be used. The thickness of each of the TCO layers is preferably between 10 and 1000 nm, preferably between 50 and 800 nm.

For a layer of mixed tin and indium oxide (ITO), this will be, for example, 250 nm thick, will be notably hot deposited, will have a square resistance of the order of 10 Ohms.

Alternatively, it may also be a layer of tin oxide doped with fluorine or antimony, or a multilayer.

Each layer of transparent conductive oxide is deposited on one of the glass panels.

Of course, the two layers of transparent conductive oxide must be connected to respective current supply connectors. These connectors, for example bus bar and wires, are respectively brought into contact with the transparent conductive oxide layer TC01 and the transparent conductive oxide layer TC02 to supply the appropriate electrical supply.

The EC electrochromic material is preferably based on tungsten oxide (cathodic electrochromic material) or iridium oxide (anodic electrochromic material). These materials can insert cations, in particular protons or lithium ions.

The CE counter-electrode is preferably made up of a neutral layer in coloring or, at least, transparent or little colored when the electrochromic layer is in the colored state. The counter electrode is preferably based on an oxide of an element chosen from tungsten, nickel, iridium, chromium, iron, cobalt, rhodium, or based on a mixed oxide d '' at least two of these, including mixed nickel and tungsten oxide. If the electrochromic material is tungsten oxide, therefore a cathodic electrochromic material, the colored state of which corresponds to the most reduced state, an anodic electrochromic material based on nickel oxide or iridium can for example be used for the counter electrode. It can in particular be a layer of mixed oxide of vanadium and tungsten or mixed oxide of nickel and tungsten. If the electrochromic material is iridium oxide, a cathodic electrochromic material, for example based on tungsten oxide, can play the role of counter-electrode. One can also use an optically neutral material in the oxidation states concerned, such as for example cerium oxide or organic materials such as electronic conductive polymers (polyaniline) or Prussian blue.

The thickness of the counter electrode is generally between 50 nm and 600 nm, in particular between 150 nm and 250 nm.

According to one embodiment, the electrolyte C1 is in the form of a polymer or a gel, in particular a proton-conducting polymer, for example such as those described in European patents EP 0 253 713 and EP 0 670 346, or a lithium ion conduction polymer, for example such as those described in patents EP 0 382 623, EP 0 518 754 or EP 0 532 408. These are then called mixed electrochromic systems.

According to another embodiment, the electrolyte C1 consists of a mineral layer forming an ionic conductor which is electrically isolated. These electrochromic systems are then designated as “all solid”. Reference may in particular be made to European patents EP 0 867 752 and EP 0 831 360. The thickness of the electrolyte layer can be between 1 nm and 1 mm. Preferably, the thickness will be between 1 and 300 nm and even more preferably between 1 and 50 nm.

An electrochromic glazing unit comprising an electrochromic stack is produced according to a manufacturing process, said stack comprising:

A first transparent electroconductive layer TC01,

A layer of an EC electrochromic material, capable of reversibly and simultaneously inserting ions, the oxidation states of which correspond to the inserted and uninserted states are of a distinct color when subjected to an appropriate power supply; one of these states having a higher light transmission than the other,

A layer of an electronically insulating and ionically conductive electrolyte

Cl,

a CE counter-electrode layer, capable of reversibly inserting ions of the same charge as that which the electrochromic material can insert, and

A second transparent electroconductive layer TC02.

A first step in the manufacturing process consists in providing two substrates or glass panels 2. The glass panels 2 used are typically float glass, possibly cut, polished and washed.

A second step consists in depositing, on each glass panel 2, at least one layer of a transparent conductive oxide TC01 / TC02. A first glass panel 2 is then obtained on which a first layer of a transparent conductive oxide TC01 is deposited and a second glass panel 2 on which is deposited a second layer of a transparent conductive oxide TC02. It will be understood that the term deposit does not mean that the layer is deposited directly on the glass panel but that it can be deposited on an already existing layer.

In a third step, the layer of an electrochromic material EC is deposited on the first glass panel 2 and the layer called the CE counter electrode is deposited on the second glass panel. 2

A fourth step consists in depositing at least the layer of ion-conducting electrolyte Cl.

This layer of ion-conducting electrolyte Cl is deposited on the layer of an electrochromic material EC or on the layer called the CE counter-electrode.

This layer of ion-conducting electrolyte C1 can be deposited in different ways.

For example, this layer can be deposited by sputtering, reactive or not, assisted by magnetic field, generally in the same vacuum installation.

In another example, this layer of ion-conducting electrolyte can be deposited in the form of a gel. Such a gel process consists in depositing the layer of ion-conducting electrolyte Cl in liquid form on the desired surface. A heat treatment is then carried out in order to obtain the desired layer of electrolyte C1 ionic conductor.

Cleverly according to the invention, a heat treatment step is carried out. This heat treatment is carried out at least on one of the transparent electroconductive layers TC01, TC02, preferably on the transparent conductive oxide layer of each glass panel 2. This heat treatment step is carried out between the second step and the third step in the manufacturing process of electrochromic glazing. In this case, the heat treatment acts only on the transparent electroconductive layers TC01, TC02. In the case of a heat treatment of the transparent electroconductive layer of each glass panel 2, each panel can be treated by a different heat treatment device or by the same treatment device.

In a variant, a so-called additional heat treatment is also applied to the layer of an electrochromic material EC and / or to the layer called the CE counter-electrode. At this time, a heat treatment stage also takes place between the third stage and the fourth stage of the process for manufacturing the electrochromic glazing. It is therefore understood that a heat treatment takes place between the second step and the third step for the treatment of at least one transparent electroconductive layer TC01, TC02 of a glass panel and that another heat treatment takes place between the third step and the fourth step for the treatment of the layer of an EC electrochromic material and / or of the layer called the CE counter-electrode.

In another variant, only one heat treatment step is provided. This heat treatment step is carried out between the third step and the fourth step of the process for manufacturing the electrochromic glazing and is arranged to heat treat the layer of an electrochromic material EC and the first transparent electroconductive layer TC01 or the counter electrode layer CE and the second transparent electroconductive layer TC02. It is therefore understood that the layers TC01 / EC - TC02 / CE of the same glass panel 2 are heat treated simultaneously. It could also be provided that the two glass panels 2 are treated at the same time. This heat treatment is carried out by a rapid heat treatment device, the latter being able to use different technologies. The term rapid heat treatment is understood to mean a heat treatment for which, locally, the layer to be treated undergoes an abrupt / abrupt rise in temperature followed by an abrupt / abrupt reduction in temperature.

In the case of laser technology, laser sources are used and are typically laser diodes or fiber lasers, in particular fiber, diode or even disc lasers. Laser diodes make it possible to economically achieve high power densities compared to the electrical power supply, for a small footprint. The size of fiber lasers is even smaller, and the linear power obtained can be even higher. The term “fiber lasers” is understood to mean lasers in which the place of generation of the laser light is spatially offset from its place of delivery, the laser light being delivered by means of at least one optical fiber. In the case of a disc laser, the laser light is generated in a resonant cavity in which is located the emitting medium which is in the form of a disc, for example a thin disc (of about 0.1 mm thick) in Yb: YAG. The light thus generated is coupled in at least one optical fiber directed towards the place of treatment. Fiber or disc lasers are preferably optically pumped using laser diodes.

The radiation from the laser sources is preferably continuous.

The wavelength of the laser radiation is in a range from 500 to 2000 nm, preferably from 700 to 1100 nm, in particular from 800 to 1000 nm. Power laser diodes emitting at one or more wavelengths chosen from 808 nm, 880 nm, 915 nm, 940 nm or 980 nm have proved to be particularly suitable. In the case of a disc laser, the wavelength is for example 1030 nm (emission wavelength for a Yb: YAG laser). For a fiber laser, the wavelength is typically 1070 nm.

In the case of non-fiber lasers, the shaping and redirection optics preferably include lenses and mirrors, and are used as means for positioning, homogenizing and focusing the radiation.

The positioning means aim, where appropriate, to arrange the radiation emitted by the laser sources along a line. They include preferably mirrors. The purpose of the homogenization means is to superimpose the spatial profiles of the laser sources in order to obtain homogeneous linear power along the line. The homogenization means preferably comprise lenses allowing the separation of the incident beams into secondary beams and the recombination of said secondary beams into a homogeneous line. The means for focusing the radiation make it possible to focus the radiation on the layer or layers of transparent conductive oxide to be treated, in the form of a line of desired length and width. The focusing means preferably comprise a focusing mirror or a converging lens.

In the case of fiber lasers, the shaping optics are preferably grouped in the form of an optical head positioned at the outlet of the optical fiber or of each optical fiber.

The optics for shaping said optical heads preferably comprise lenses, mirrors and prisms and are used as means for transforming, homogenizing and focusing the radiation.

The transformation means comprise mirrors and / or prisms and serve to transform the circular beam, obtained at the output of the optical fiber, into a non-circular, anisotropic beam, in the form of a line. For this, the transformation means increase the quality of the beam along one of its axes (fast axis, or axis of width I of the laser line) and decrease the quality of the beam along the other (slow axis, or axis of the length L of the laser line).

The homogenization means superimpose the spatial profiles of the laser sources in order to obtain homogeneous linear power along the line. The homogenization means preferably comprise lenses allowing the separation of the incident beams into secondary beams and the recombination of said secondary beams into a homogeneous line.

Finally, the means for focusing the radiation make it possible to focus the radiation at the working plane, that is to say in the plane of the layer to be treated, in the form of a line of desired length and width. The focusing means preferably comprise a focusing mirror or a converging lens.

When only one laser line is used, the length of the line is advantageously equal to the width of the substrate. This length is typically at least 1 m, in particular at least 2 m and in particular at least 3 m. It is also possible to use several lines, disjointed or not, but arranged so as to treat the entire width of the substrate. In this case, the length of each laser line is preferably at least 10 cm or 20 cm, in particular within a range from 30 to 100 cm, in particular from 30 to 75 cm, or even from 30 to 60 cm.

The term "length" of the line means the largest dimension of the line, measured at the surface of the transparent conductive oxide layer, and "width" the dimension in a second direction perpendicular to the first. As is customary in the field of lasers, the width (w) of the line corresponds to the distance, in this second direction, between the axis of the beam where the radiation intensity is maximum and the point where the radiation intensity is equal to 1 / e ² times the maximum intensity. If the longitudinal axis of the laser line is named x, we can define a width distribution along this axis, called w (x).

The average width of the or each laser line is preferably at least 35 micrometers, in particular lying in a range from 40 to 100 micrometers or from 40 to 70 micrometers. Throughout this text, "average" means the arithmetic average. Over the entire length of the line, the width distribution is narrow in order to limit as far as possible any heterogeneity of treatment. Thus, the difference between the largest width and the smallest width is preferably at most 10% of the value of the average width. This figure is preferably at most 5% and even 3%.

The laser modules are preferably mounted on a rigid structure, called a "bridge", based on metallic elements, typically made of aluminum. The structure preferably does not include a marble slab. The bridge is preferably positioned parallel to the conveying means conveying the substrate so that the focal plane of the laser line remains parallel to the surface of the substrate to be treated. Preferably, the bridge comprises at least four feet, the height of which can be individually adjusted to ensure parallel positioning in all circumstances. The adjustment can be ensured by motors located at each foot, either manually or automatically, in conjunction with a distance sensor. The height of the bridge can be adjusted (manually or automatically) to take into account the thickness of the substrate to be treated, and thus ensure that the plane of the substrate coincides with the focal plane of the laser line. The linear power of the laser line is preferably at least 50 W / cm, advantageously 100 W / cm, in particular 200 W / cm, even 300 W / cm and even 400 W / cm. It is even advantageously at least 600 W / cm, in particular 800 W / cm, or even 1000 W / cm. The linear power is measured at the point where the or each laser line is focused on the transparent conductive oxide layer. It can be measured by placing a power detector along the line, for example a calorimetric power meter, such as in particular the Beam Finder S / N 2000716 power meter from the company Cohérent Inc. The power is advantageously distributed in a manner homogeneous over the entire length of the or each line. Preferably, the difference between the highest power and the lowest power is less than 10% of the average power.

According to a preferred embodiment, the radiation comes from at least one intense pulsed light lamp (IPL, Intense Pulsed Light) hereinafter called flash lamp.

Such flash lamps are generally in the form of sealed glass or quartz tubes filled with a rare gas, provided with electrodes at their ends. Under the effect of a short-lived electric pulse, obtained by discharging a capacitor, the gas ionizes and produces a particularly intense incoherent light. The emission spectrum generally comprises at least two emission lines, it is preferably a continuous spectrum having a maximum emission in the near ultraviolet.

The lamp is preferably a xenon lamp. It can also be an argon, helium or krypton lamp. The emission spectrum preferably comprises several lines, in particular at wavelengths ranging from 160 to 1000 nm.

The duration of each light pulse is preferably in a range from 0.05 to 20 milliseconds, in particular from 0.1 to 5 milliseconds. The repetition rate is preferably within a range from 0.1 to 5 Hz, in particular from 0.2 to 2 Hz.

The radiation can come from several lamps arranged side by side, for example 5 to 20 lamps, or even 8 to 15 lamps, so as to simultaneously treat a larger area. In this case, all the lamps can emit flashes simultaneously. The or each lamp is preferably arranged transversely to the longest sides of the substrate. The or each lamp preferably has a length of at least 1 m, in particular 2 m and even 3 m, so that large substrates can be treated.

The capacitor is typically charged at a voltage of 500 V to 500 kV. The current density is preferably at least 4000 A / cm ² . The total energy density emitted by flash lamps, related to the surface of the transparent conductive oxide layer, is preferably between 1 and 100 J / cm ² , in particular between 1 and 30 J / cm ² , or even between 5 and 20 J / cm ² .

The high powers and energy densities make it possible to heat the layer to be treated very quickly at high temperatures.

During the annealing step of the layer to be treated of the process according to the invention, each point of the layer to be treated is preferably brought to a temperature of at least 300 ° C., in particular 350 ° C., or even 400 ° C. , and even 500 ° C or 600 ° C. The maximum temperature is normally reached at the moment when the point of the layer to be treated in question passes under the radiation device, for example under the laser line or under the flash lamp. At a given instant, only the points on the surface of the layer located under the radiation device (for example under the laser line) and in its immediate surroundings (for example within one millimeter) are normally at a temperature of at least 300 ° C. For distances to the laser line (measured along the direction of travel) greater than 2 mm, in particular 5 mm, including downstream of the laser line, the temperature of the electrochromic stack is normally at most 50 ° C., and even 40 ° C or 30 ° C.

Each point of the layer to be treated undergoes heat treatment (or is brought to the maximum temperature) for a period advantageously comprised in a range ranging from 0.05 to 10 ms, in particular from 0.1 to 5 ms, or from 0, 1 to 2 ms. In the case of treatment using a laser line, this duration is fixed both by the width of the laser line and by the speed of relative movement between the substrate and the laser line. In the case of treatment with a flash lamp, this duration corresponds to the duration of the flash.

The speed of the relative movement of movement between the substrate and the or each source of radiation (in particular the or each laser line) is advantageously at least 2 m / min or 4 m / min, in particular 5 m / min and even 6 m / min or 7 m / min, or even 8 m / min and even 9 m / min or 10 m / min. According to certain embodiments, in particular when the absorption of radiation by the electrochromic stack is high or when the electrochromic stack can be deposited with high deposition rates, the speed of the relative movement of movement between the substrate and the source radiation (in particular the or each laser line or flash lamp) is at least 12 m / min or 15 m / min, in particular 20 m / min and even 25 or 30 m / min. In order to ensure treatment that is as homogeneous as possible, the speed of the relative movement of movement between the substrate and the or each source of radiation (in particular the or each laser line or flash lamp) varies during treatment by at most 10 % relative, in particular 2% and even 1% compared to its nominal value.

Preferably, the or each radiation source (in particular laser line or flash lamp) is fixed, and the substrate is in motion, so that the relative displacement speeds will correspond to the speed of movement of the substrate.

This rapid heat treatment cleverly makes it possible to activate said transparent electroconductive layers, that is to say to increase the conductivity while limiting crystallization. This limitation in crystallization is manifested by a limitation in the size of the crystals formed during this annealing step since the latter does not vary. For example, for ten 10cm ² samples comprising an ITO layer, half of these samples are not heat treated and half are heat treated. It is noted that the average value of the size of the crystals is 33.3 nm without heat treatment and 34.7 nm with laser treatment.

In a sixth step, an assembly step, called the lamination step, is performed to assemble the two glass panels.

Thus, advantageously, this ability to increase the electrical conduction of the transparent electroconductive layers without increasing the size of the crystals and therefore the roughness makes it possible to improve the performance of the electrochromic glazing. In fact, during assembly of the glass panels 2, a constraint appears at the level of the electrolyte layer C1. This constraint is the result of the roughness of the transparent conductive layers TC01, TC02 on said electrolyte layer, this locally deformed / compressing electrolyte layer so that said electrolyte layer C1 locally has a variation in sound thickness. This local variation in the thickness of the electrolyte layer C1 over its entire surface results in an electrochromic reaction of the electrochromic glazing which is not homogeneous and therefore a drop in performance.

In addition, with a decrease in roughness following this rapid heat treatment, it then becomes possible to have the weakest possible layer of ion-conducting electrolyte and electrical insulator. Indeed, with a high roughness, it is necessary to provide a layer of ion-conducting electrolyte and electrical insulator Cl having a thickness which compensates for the variation in thickness due to this roughness in order to keep satisfactory optical performance. However, an increase in the thickness of the layer of ion-conducting electrolyte Cl leads to a decrease in the speed of passage of the electrochromic glazing from light to opaque mode and vice versa.

Thus, a lower roughness therefore makes it possible to less compensate for the variation in thickness and therefore to have a thinner layer of ion-conducting electrolyte and electrical insulator. The speed of passage of the electrochromic glazing from clear mode to opaque mode and vice versa is therefore better.

Of course, the present invention is not limited to the illustrated example but is susceptible to various variants and modifications which will appear to those skilled in the art.

Claims

1. Method for manufacturing an electrochromic glazing, said glazing comprising an electrochromic stack comprising:

a first transparent conductive layer (TC01),

a layer of electrochromic material (EC),

a layer of an ion-conducting electrolyte (Cl),

a counter electrode layer (CE),

a second transparent conductive layer (TC02),

said method comprising the following steps:

- provide a first glass panel (2) and a second glass panel (2);

- depositing a first transparent conductive layer (TC01) on the first glass panel and a second transparent conductive layer (TC02) on the second glass panel;

- deposit a layer of an electrochromic material (EC) on the first transparent conductive layer (TC01) and a counter-electrode layer (CE) on the second transparent conductive layer (TC02);

- deposit the layer of an ion-conducting electrolyte (Cl) on one or the other of the layers of an electrochromic material (EC) or counter-electrode (CE);

- assemble the two glass panels to form a laminated glazing

Characterized in that it further comprises at least one heat treatment step consisting in thermally treating at least one glass panel provided with at least one transparent conductive layer (TC01, TC02) by a rapid heat treatment device before to assemble the glass panels.

2. The method of claim 1, wherein said heat treatment step is used to treat the transparent conductive layer of each glass panel.

3. The method of claim 1, wherein a heat treatment step is further used to treat the layer of an electrochromic material (EC) and / or the layer of a counter electrode (CE).

4. Method according to one of claims 1 to 3, wherein said step of heat treatment of said at least one transparent conductive layer is carried out after the deposition of the first transparent conductive layer (TC01) on the first glass panel and / or the second transparent conductive layer (TC02) on the second glass panel.

5. Method according to one of the preceding claims, in which said heat treatment step used to treat the layer of an electrochromic material (EC) and / or the layer of a counter electrode (CE) is carried out after the deposition of the layer of an electrochromic material (EC) and / or the layer against the electrode (CE).

6. Method according to one of the preceding claims, wherein said heat treatment step is carried out to simultaneously treat the layer of an electrochromic material (EC) and the first transparent conductive layer or to simultaneously treat the counter-electrode layer (CE ) and the second transparent conductive layer.

7. Method according to one of the preceding claims, wherein the heat treatment device is placed opposite the layer to be treated and in that the heat treatment step is arranged to bring the layer to be treated to a temperature at least equal to 300 ° C for a short time, preferably less than 100 milliseconds.

8. Method according to one of the preceding claims, in which the heat treatment device is arranged to heat treat the layer to be treated for a short time, preferably less than 100 milliseconds.

9. The method of claims 7 or 8, wherein the heat treatment device is a laser device emitting radiation having a wavelength between 300 and 2000 nm.

10. The method of claims 7 or 8, wherein the heat treatment device comprises at least one intense pulsed light lamp emitting radiation having a wavelength between 160 and 1000 nm, the heat treatment step being arranged for that each light pulse has a duration preferably in a range from 0.05 to 20 milliseconds.