EP2539419A1

EP2539419A1 - Electroactive material

Info

Publication number: EP2539419A1
Application number: EP11712615A
Authority: EP
Inventors: Samuel Solarski; Fabienne Piroux; Gilles Bokobza
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: 2010-02-23
Filing date: 2011-02-22
Publication date: 2013-01-02
Also published as: FR2956667A1; CN102803435A; WO2011104472A1; FR2956667B1; US20120307338A1

Abstract

The invention relates to an electroactive material for an electrically controllable device having variable optical/energy properties, the material being in the form of a self-supported layer, and including or consisting of a matrix which is capable of ensuring the mechanical resistance of the material, and in which an electroactive system is incorporated which is made from at least one electroactive organic compound (ea/), at least one electroactive organic compound (ea2), and ionic charges which, by means of an electrical current, enable redox reactions of said organic compounds to occur, said organic compounds and ionic charges being in a solubilized state due to a solubilizing liquid (L) inside the matrix. The matrix consists of a textile lap (NT) or a stack of laps including at least one textile lap (NT), the textile lap or the stack being translucent or transparent (e) once impregnated (e) with the liquid (L) which solubilized the organic compounds and the ionic charges, and capable of at least partially preserving the integrity thereof once impregnated (e) with the liquid (L).

Description

ELECTROACTIVE MATERIAL

The present invention relates to an electroactive material for electrically controllable device said variable optical properties and / or energy, said electroactive material containing organic compounds redox activity respectively positive and negative, a method and a kit for manufacturing this material, on a electrically controllable device and glazings using such an electroactive material.

The present invention relates to an electroactive material for electrically controllable device with variable optical / energy properties, said material being in the form of a self-supporting layer and comprising or consisting of a matrix which is capable of ensuring the mechanical strength of said electroactive material and in which is inserted an electroactive system formed by:

at least one electroactive organic compound (ea) capable of being reduced and / or of accepting electrons and cations acting as compensation charges;

at least one electroactive organic compound (ea ₂ ) capable of oxidizing and / or ejecting electrons and cations acting as compensation charges;

at least one of said electroactive organic compounds

(eai ⁺ et ea ₂ ) being electrochromic to obtain a color contrast; and

ionic charges capable of allowing, under the action of an electric current, oxidation and reduction reactions of said electroactive organic compounds (ea and ea ₂ ), which are necessary to obtain the color contrast; said electroactive compounds (ea & ea ₂ ) and said ionic charges being within said matrix in the solubilized state by a solubilizing liquid (L), which is also capable of solubilizing the reduced and oxidized species (eai &ea); ₂ ⁺ ) respectively associated with said electroactive compounds (ea & ea ₂ );

said matrix being further selected to provide the percolation path to said ionic charges.

The solubilizing liquid (L) solubilizing said electroactive compounds and said ionic charges has sometimes been referred to hereinafter as "electroactive solution".

By "cations acting as compensation charges" are meant ions Li ⁺ , H ⁺ , etc., which can be inserted into or disinsert in the electroactive compounds at the same time as the electrons.

An electroactive organic compound capable of being reduced and / or of accepting electrons and cations acting as compensation charges means a compound with negative redox activity, which may be a cathodic electrochromic or a non-electrochromic compound, then playing only the role of reservoir ionic charges or against electrode.

An electroactive organic compound capable of oxidizing and / or ejecting electrons and cations acting as compensation charges means a compound with a positive redox activity, which may be an anodic electrochrome or a non-electrochromic compound. , playing then only the role of reservoir ionic charges or against electrode.

Assuming that the compound (ea) is electrochromic (e.g., 1,1'-diethyl-4,4'-bipyridinium diperchlorate) and that the compound (ea ₂ ) is electrochromic (being for example 5,10-dihydro-5,10-dimethylphenazine) or non-electrochromic being for example a ferrocene), the redox reactions which are established under the action of the electric current are as follows:

Colored

Colorful if electrochromic

Colorless if not electrochromic In accordance with a first state of the art, the electroactive material comprises a solution or a gel containing the electroactive organic compounds (e.g. E ₂ ). It may in particular be mentioned the electroactive materials in the form of gels more or less viscous material based on a polymer such as poly (ethylene oxide) and poly (methyl methacrylate), electroactive organic compounds - anodic and cathodic - at least one being electrochromic, one or more ionic salts and one or more solvents and additives.

According to a second state of the art, the electroactive material comprises a self-supporting polymer matrix in which are inserted the electroactive organic compound (s) (ea & ea ₂ ) and the ionic charges, said polymer matrix containing within it a liquid (L) solubilizing said electroactive compounds (eai ⁺ & ea ₂ ) as well as the reduced and oxidized species respectively associated (eai and ea ₂ ⁺ ) and said ionic charges but not solubilizing said self-supporting polymer matrix, the latter being chosen to ensure a percolation path ionic charges to allow said oxidation and reduction reactions of said electroactive organic compounds (ea & ea ₂ ).

Such an electroactive material is described in PCT International Application WO 2009/007601 in the name of the Applicant Company.

According to a third state of the art, the electroactive material is a self-supported polymer film and plasticized with a liquid containing the electroactive organic compounds (ea & ea ₂ ) as in the patent application WO2006 / 008776.

In general, it is sought to obtain electrically controllable devices having:

a good mechanical strength of the electroactive material;

the fastest possible staining and fading rates;

a thickness of the electroactive material that is sufficient to absorb the flatness defects of the substrates, such as tempered glass for example, and to guarantee homogeneous discolored and colored states, that is to say with the same level of absorption whatever the area of the device considered;

a transition in coloration - discoloration as homogeneous as possible, ie without a gradient of coloring of the edges towards the center (halo effect) during the transient stages of coloration or discoloration; and

a high contrast between the colored state and the discolored state.

The different states of the art above all have disadvantages:

The electroactive gel can flow while it has been put in place in the electrically controllable device (such as glazing), which will lead to leaks rendering the device unusable. The techniques of setting up the gel in the electrically controllable devices are complicated to implement, consisting of a filling ("back-filling") possibly under vacuum, sometimes followed by a polymerization step. In addition, it is difficult to drive all the air during this filling. Finally, for large glazing, the large size of the equipment needed to deposit the electroactive material or ensure the filling by the gel becomes prohibitive.

In the case of the polymer film impregnated with an electroactive solution, the development of the film can be very difficult because the film must ensure the mechanical strength of the electroactive material, have a sufficient porosity to allow, after impregnation, the percolation of the ionic charges over the entire thickness of the electroactive material and especially not be solubilized or converted into a gel in the solvent of the electroactive solution even when the electrically controllable device is subjected to temperatures up to 80 ° C, or even beyond. Polymeric films meeting these criteria are otherwise expensive and not very durable, risking tearing with manipulation during the manufacture of the device or bursting over time, leading then to a loss of the percolation network and to loss of mechanical strength with gel formation. Polymeric films having after impregnation sufficient porosity to allow the percolation of ionic charges over the entire thickness of the electroactive material are generally thin, with thicknesses of less than 150-200 pm, which can not be absorbed flatness defects of the substrate which can for example reach several tens of microns, or even hundred microns, in the case of tempered glass. The self-supporting and plasticized polymer film has the disadvantage of imposing thin thicknesses, generally less than 100-200 μm, to guarantee acceptable coloration and discoloration rates because the diffusion rate of the electroactive compounds in the self-supporting and plasticized polymer film is very low. slow. In addition, the polymer self-supported and plasticized at room temperature is very often converted into a gel at 80 ° C, which is a temperature achievable if the device is used outside, in the sun, which may lead to leakage by casting the electroactive material, rendering the device unusable under such conditions.

The present invention provides a solution to these disadvantages and proposes to use, as a matrix, at least one textile web, which makes it possible to have an electroactive material several hundred microns thick and easy to use thereof. by impregnating the textile ply or plies in the electroactive solution. The resulting self-supporting electroactive material, which will be durable, and whose thickness of several hundred microns will absorb the unevenness of the substrates, can then be simply deposited on the substrate. The choice of a textile web also offers the possibility of mixing different types of fibers, some of them being able to gel in the presence of the solubilizing liquid of the electroactive compounds and fillers, the gel-fiber combination being even reinforced creep resistance and can increase the tack (ability to stick) of the resulting electroactive material, which leads to an increase in the mechanical strength of the device. The subject of the present invention is therefore an electroactive material for an electrically controllable device with variable optical / energy properties, as defined at the very beginning of this description, said device being characterized by the fact that the matrix is based on a textile web (NT ) or a stack of webs including at least one textile web (NT), said textile web (NT) or said stack being translucent or transparent (e) once impregnated (e) by the liquid (L) having solubilized said compounds electroactives (ea & ea ₂ ) and the ionic charges, and being able to retain at least part of its integrity once impregnated (e) by the liquid (L) so that the holding of said electroactive material is ensured.

In other words, the textile web (NT) or a textile web (NT) as defined above can be said to be at least partially insoluble in the liquid (L).

The textile web (NT) or a textile web (NT) may have a non-woven or matte web architecture, woven or knitted fabric, this non-woven or mat veil, this woven fabric or knit fabric being optionally coated with a binder, which may be at least partially soluble in the liquid (L) to form a gel.

The terms "nonwoven web" and "mat" are each defined as a film structure with non-woven fibers, not knitted together.

The terms "woven" and "knitted" are defined as a matrix made of fibers and / or threads respectively woven or knitted.

Fabrics and knits have the advantage of a good cohesion of the son between themselves in the absence of a binder. The binder, when it is used, makes it possible, in particular, to slightly gel the liquid of solubilization (L), further improving the mechanical strength of the electroactive material or even the tackiness of the resulting electroactive material on the substrates.

Each textile web (NT) may be composed of one or more types of fibers or yarns, the yarns being defined as assemblies of several fibers.

The textile web (NT) or a textile web (NT) is in particular based on synthetic fibers and / or yarns (artificial), chosen in particular from fibers and / or polyolefin yarns such as polypropylene (PP), polyester, fluorinated polymer such as polytetrafluoroethylene (PTFE) or fluorinated polyvinylidene (PVDF), polyamide or polyimide and / or based on mineral fibers such as glass fibers, and / or based on fibers and / or natural threads, such as than fibers and / or cotton or woolen threads.

According to a first variant, the textile web (NT) or a textile web (NT) is based on fibers and / or single-component or multicomponent yarns, the fibers and / or multicomponent yarns being in particular fibers and / or hybrid yarns or yarns. fibers and / or yarns comprising a core of a chemical resistance material, able to maintain its integrity during impregnation with the solubilizing liquid (L) in order to ensure the mechanical strength of the electroactive material, and at least one cladding a material soluble in the solubilizing liquid (L) or capable of giving a gel during the impregnation of the textile web (NT) or the stack of webs with the impregnating liquid (L).

Examples of hybrid yarns include Twintex ® (Owens Corning) fibers which combine glass and polypropylene. According to a second variant, the textile web (NT) or a textile web (NT) is based on fibers and / or threads insoluble in the solubilizing liquid (L) and fibers and / or son soluble in the liquid of solubilization (L), the fibers and / or son thus solubilized having led to the formation of a gel. The amount of fibers and / or insoluble son relative to the amount of fibers and / or soluble son will be chosen so that the mechanical strength of the electroactive material is ensured.

Systems combining fibers and gel will be mechanically more resistant than a system based on fibers and liquids.

According to a third variant, the textile web (NT) or a textile web (NT) of the stack is a textile web (NT) coated with a material soluble in the solubilizing liquid (L) or capable of giving a gel during the impregnation of the textile web or the stack of webs with the solubilization liquid (L); mention may be made of the use of polymer-coated fabrics or fabrics such as silicone-coated glass fabrics marketed by the company "Saint-Gobain Performance Plastique" under the trade name COHRlastic®, the liquid (L) swelling or solubilizing the polymer of enduct ion.

The textile web (NT) or a textile web (NT) may have a thickness of 50 μm to 4 mm, the fibers having a diameter of 50 nm to 100 μm. In the electroactive device, it will be preferred to use 400 μm to 1 mm thick textile plies composed of fibers with a diameter of between lpm and 20 μm. For the matrix, it is possible to use fibers or threads of the same diameter or of different diameters. It may be mentioned the use of a single textile web (NT) or a stack of several textile webs (NT), the latter being identical or of different natures, and / or different diameters son.

The electroactive organic compound (s)

(eai ⁺ ) may be chosen from bipyridiniums or viologenes such as 1,1'-diethyl-4,4'-bipyridinium diperchlorate, pyraziniums, pyrimidiniums, quinoxaliniums, pyryliums, pyridiniums, tetrazoliums, Verdazyls, quinones, quinodimethanes, tricyanovinylbenzenes, tetracyanoethylene, polysulfides and disulfides, as well as all electroactive polymeric derivatives, such as polyviologenes, of the electroactive compounds just mentioned.

The electroactive organic compound (s) (ea ₂ ) can be chosen from metallocenes, such as cobaltocenes, ferrocenes, Ν, Ν, Ν ', Ν'-tetramethylphenylenediamine (TMPD), phenothiazines such as phenothiazine, dihydrophenazines and the like. such as 5,10-dihydro-5,10-dimethylphenazine, reduced methylphenothiazone (MPT), methylene violet bernthsen (MVB), verdazyls, as well as all the electroactive polymeric derivatives of the electroactive compounds just mentioned .

The ionic charges may be borne by at least one of said electroactive organic compounds and / or by at least one ionic salt and / or at least one acid solubilized in said liquid (L) and / or by said matrix.

The solubilizing liquid (L) may consist of a solvent or a mixture of solvents and / or at least one ionic liquid or molten salt at room temperature, said ionic liquid or molten salt or said ionic liquids or molten salts then constituting a solubilizing liquid carrying ionic charges, which represent all or part of the ionic charges of said electroactive system.

The ionic salt (s) may be chosen in particular from lithium perchlorate, trifluoromethanesulfonate or triflate salts, trifluoromethanesulfonylimide salts and ammonium salts.

The acid or acids may be chosen in particular from sulfuric acid (H ₂ SO ₄ ), triflic acid (CF ₃ SO ₃ H), phosphoric acid (H ₃ PO ₄ ) and polyphosphoric acid (H _{n +2} P _n 0 _3n + i) ·

The solvent or solvents may be chosen in particular from sulfolane; dimethylsulfoxide; dioxane; amides such as N, -dimethylformamide, N, N-dimethylacetamide; 1-methyl-2-pyrrolidinone; carbonates, such as propylene carbonate, ethylene carbonate, butylene carbonate; ethylene glycols such as tetraglyme; alcohols, such as ethanol, ethoxyethanol; ketones, such as cyclopentanone, benzylacetone; lactones, such as gamma-butyrolactone, acetylbutyrolactone; nitriles, such as acetonitile, glutaronitrile, 3-hydroxypropionitrile; anhydrides, such as acetic anhydride; ethers such as 2-methoxyethyl ether; the water ; phthalates; adipates; citrates; sebacates; maleates; benzoates and succinates.

The ionic liquid or liquids may be chosen in particular from imidazolium salts, such as 1-ethyl-3-methylimidazolium tetrafluoroborate (emim-BF ₄ ), 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (emim-CF ₃ SC > 3), 1-ethyl-3-methylimidazolium bis (trifluoromethylsulphonyl) imide (emim- (CF ₃ SO ₂ ) ₂ or emim- TSFI) and 1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide (bmim- (CF3SO2) 2 or bmim-TSFI).

The concentration of the ionic salt (s) and / or acid (s) in the solvent or solvent mixture is in particular less than or equal to 5 moles / liter, preferably less than or equal to 2 moles / liter, more or less more preferred, less than or equal to 1 mole / liter.

The or each solvent may be selected from those having a boiling point of at least 70 ° C, preferably at least 150 ° C.

The solubilizing liquid (L) may also contain at least one thickening agent, which will solubilize in said liquid (L) so as to form a gel.

The thickening agent may especially be chosen from:

the homo- or copolymers having no ionic charges, in which case they are borne by at least one aforementioned electroactive organic compound and / or by at least one ionic salt or solubilized acid and / or by at least one ionic liquid or molten salt;

the homo- or copolymers comprising ionic charges, in which case additional charges making it possible to increase the rate of percolation can be borne by at least one aforementioned electroactive organic compound and / or by at least one solubilized ionic or acidic salt and / or by at least one ionic liquid or molten salt; and

mixtures of at least one homo- or copolymer not carrying ionic charges and at least one homo- or copolymer containing ionic charges, to which in the case of additional fillers making it possible to increase the percolation rate may be carried by at least one aforementioned electroactive organic compound and / or by at least one ionic salt or solubilized acid and / or with at least one ionic liquid or molten salt.

The thickening agent may also be chosen from copolymers of ethylene, vinyl acetate, ethylene-vinyl acetate (EVA), polyurethanes (PU), polyvinyl butyral (PVB), polyimides (PI) polyamides (PA), polystyrene (PS), polyvinylidene fluoride (PVDF), polyether ketones (PEK), polyether ether ketones (PEEK), epichlorohydrin copolymers, polyolefins poly (ethylene oxide) (POE), polyacrylates, poly (methyl methacrylate) (PMMA), silicones or their derivatives or their monomers or their prepolymers.

The thickening agent may also be chosen from polyelectrolytes and in particular sulphonated polymers which have been exchanged for H ⁺ ions of SO ₃ H groups by the ions of the desired ionic charges. The sulphonated polymers are especially chosen from sulphonated tetrafluoroethylene copolymers, sulphonated polystyrenes (PSS), sulphonated polystyrene copolymers, poly (2-acrylamido-2-methyl-1-propanesulphonic acid) (PAMPS), polyetheretherketones (PEEK ) sulphonated and sulphonated polyimides.

The matrix may also be formed by a stack of webs, which comprises, apart from the textile web or sheets (NT) at least partly insoluble in the liquid (L), at least one non-textile web (NNT) in which the solubilizing liquid (L) has penetrated to heart to inflate or solubilize, and / or at least one textile web (T ') soluble in the liquid (L). A "non-textile web" is defined as a polymer web without a fibrous matrix.

The polymer constituting at least one polymeric web of the matrix as defined in the preceding paragraph may be a homo- or copolymer in the form of a nonporous film but capable of swelling in said liquid, or in the form of a porous film, said porous film possibly being able to swell in the liquid having ionic charges and whose porosity after swelling is chosen to allow the percolation of the ionic charges in the thickness of the film impregnated with liquid. The polymer constituting at least one sheet may also be soluble in said liquid (L).

The polymer constituting at least one polymer web may also be chosen from:

mixtures of at least one homo- or copolymer not carrying ionic charges and at least one homo- or copolymer containing ionic charges, in which case additional charges making it possible to increase the percolation rate may be carried by at least at least one electroactive organic compound and / or at least one ionic salt or solubilized acid and / or at least one ionic liquid or molten salt.

The polymer or polymers of a polymer web may or may be chosen from copolymers of ethylene, vinyl acetate, ethylene-vinyl acetate (EVA), polyurethanes (PU), polyvinyl butyral (PVB) polyimides (PI), polyamides (PA), polystyrene (PS), polyvinylidene fluoride (PVDF), polyetherketones (PEK), polyether ether ketones (PEEK), copolymers epichlorohydrin, polyolefins, poly (ethylene oxide) (POE), polyacrylates, poly (methyl methacrylate) (PMMA), silicones or their derivatives or their monomers or their prepolymers.

The polymer or polymers of a polymer web may or may also be chosen from polyelectrolytes and especially sulphonated polymers which have been subjected to an exchange of H ⁺ ions of SO ₃ H groups by the ions of the desired ionic charges, this ion exchange having taken place before and / or simultaneously with the impregnation, the matrix constituted by the stacking of the textile ply (s) (NT) with the polymer ply (s) in the electroactive solution, the sulfonated polymers being especially chosen from copolymers sulfonated tetrafluoroethylene, sulfonated polystyrenes (PSS), sulfonated polystyrene copolymers, poly (2-acrylamido-2-methyl-1-propane sulfonic acid) (PAMPS), sulfonated polyether ether ketones (PEEK) and sulfonated polyimides.

Moreover, the matrix, consisting of at least one textile web (NT), and the liquid (L) are advantageously chosen so that the active medium resists a temperature corresponding to the temperature required for a subsequent lamination or calendering step, namely a temperature of at least 80 ° C, in particular at least 100 ° C.

The materials constituting the matrix and the solubilizing liquid (L) may have different or substantially equal indices. It will be preferred that the indices be substantially equal, with a difference of at most 0.10, or even at most 0.05, so as to reduce the blurriness of the device.

By way of example, the matrix consists of a sheet of glass fibers, for example of glass E (with a theoretical index of about 1.55), and the solubilizing liquid (L) consists of phthalate of dimethyl (theoretical index of about 1.515). According to another example, the matrix consists of a sheet of polyvinylidene fluoride (PVDF) fibers (theoretical index of about 1.42), and the solubilizing liquid (L) consists of carbonate propylene (theoretical index 1, 422).

The subject of the present invention is also a process for producing an electroactive material as defined above in the context of the present invention, characterized in that the impregnation of said matrix consisting of at least one tablecloth is carried out. textile (NT) by the solubilization liquid (L) having solubilized said electroactive system, and is then carried out if necessary a dewatering.

The immersion can be carried out for a period of 2 minutes to 3 hours. The immersion may be carried out under heating, for example at a temperature of 40 to 80 ° C. Immersion can also be performed using ultrasound to help penetrate the electroactive solution into the matrix.

Also, the present invention also relates to a kit for manufacturing electroactive material as defined above in the context of the present invention, characterized in that it consists of:

a matrix as defined above in the context of the present invention, capable of ensuring the mechanical strength of the electroactive material; and

a solubilizing liquid (L) of the electroactive system as defined above in the context of the present invention, wherein said electroactive system has been solubilized.

The present invention also relates to an electrically controllable device with variable optical / energy properties, comprising the following stack of layers:

a first glass-function substrate (VI);

a first electronically conductive layer (TCC1) with an associated current supply;

an electroactive material;

a second electronically conductive layer (TCC2) with an associated current supply; and

a second substrate with a glass function (V2),

characterized in that the electroactive material is as defined above in the context of the present invention.

The substrates with a glass function are chosen in particular from glass (float glass, etc.) and transparent polymers, such as poly (methyl methacrylate) (PMMA), polycarbonate (PC) and polyethylene. terephthalate) (PET), poly (ethylene naphthoate) (PEN) and cycloolefin copolymers (COC).

In the context of the present invention, the electronically conductive layers used are "TCC", an abbreviation for the expression "Transparent Conductive Coating", an example of which is a conductive transparent oxide TCO ("Transparent Conductive

Oxide ").

The electronically conductive layers can also comprise a grid or a microgrid or be in the form of a grid or a microgrid; they may also comprise an organic and / or inorganic sub-layer, especially in the case of plastic substrates.

The electronically conductive layers are in particular metal-type layers, such as layers of silver, gold, platinum and copper; or transparent conductive oxide (TCO) layers, such as tin doped indium oxide (I n ₂ 0 ₃ i Sn or ITO), indium oxide doped with antimony (I n203 i Sb), fluorine doped tin oxide (Sn0 ₂ : F) and aluminum doped zinc oxide (ZnO: Al); or TCO / metal / TCO multilayers, the TCO and the metal being in particular chosen from those enumerated above; or NiC _r / metal / NiC _r multilayers, the metal being in particular chosen from those enumerated above.

When the electrochromic system is intended to work in transmission, the electroconductive materials are generally transparent oxides whose electronic conduction has been amplified by doping such as In ₂ 0 ₃ : Sn, In ₂ O ₃ : Sb, ZnO: Al or SnO ₂ F. Indium tin doped oxide (In ₂ 0 ₃ : Sn or ITO) is frequently selected for its conductivity properties high electronics and low light absorption. Alternatively or in a complementary manner, when the system is intended to work in reflection, one of the electroconductive materials may be metallic in nature.

The electrically controllable device of the present invention may be configured to form:

a motor vehicle roof, which can be activated autonomously, or a side window or a rear window for a motor vehicle or a rear-view mirror;

- a windshield or a portion of the windshield of a motor vehicle, an airplane or a ship, an automobile roof;

an airplane porthole;

- glazing for cranes, construction machinery, tractors;

a display panel of graphical and / or alphanumeric information;

- an interior or exterior glazing for the building; - a roof window;

- a display, a store counter;

a protective glazing of an object of the table type; an anti-glare computer screen;

- glass furniture;

- a separating wall of two rooms inside a building.

The electrically controllable device according to the invention can operate in transmission or in reflection.

The substrates may be transparent, flat or curved, clear or tinted in the mass, opaque or opacified, polygonal in shape or at least partially curved. At least one of the substrates may incorporate another feature such as solar control, anti-reflective or self-cleaning functionality.

The present invention also relates to a method of manufacturing the electrically controllable device as defined above in the context of the present invention, characterized in that it assembles the various layers that compose it by calendering or laminating optionally under heating.

The present invention finally relates to a single or multiple glazing, characterized in that it comprises an electrically controllable device as defined above in the context of the present invention.

The various layers composing said system can be assembled in single or multiple glazing.

The following Examples illustrate the present invention without however limiting its scope. In these examples, TL designates the light transmission, and L *, a *, b * are defined as the colorimetric quantities in the CIELab space.

The "K-glass ™" glass used in these examples is a glass coated with an electroconductive layer of SnC> 2: F with a surface resistance R _n equal to 20.5Ω / _Π (glass sold under this name by the Company). "Pilkington").

EXAMPLE 1 Preparation of an Electrochromic Cell

- SnC layered glass> 2: F

- electroactive material: non-woven glass fleece + ferrocene + 1,1'-diethyl-4,4'-bipyridinium diperchlorate + lithium perchlorate + propylene carbonate - SnC layered glass> 2: F

A solution of propylene carbonate containing 0.06 mol.LT ¹ ferrocene, 1,1'-diethyl-4,4'-bipyridinium diperchlorate at 0.06 mol.LT ¹ and lithium perchlorate was prepared. at 0.15 mol.LT ¹ . The solution was stirred for 30 minutes.

This solution was impregnated with a non-woven glass veil, obtained dry, with a thickness of 500 μm, having fibers 13 μm thick.

The impregnated web was extended on a "K-glass ™" glass substrate on the electroconductive layer side. Double-sided adhesive strips were placed around the periphery and then covered with a second "K-glass ™" glass substrate, on the electroconductive layer side facing the impregnated web. The electrochromic device thus manufactured, whose active surface area is 8 × 8 cm ^2, was calendered.

The performances of this electrochromic device are given in Table 1 below:

Table 1

EXAMPLE 2 Preparation of an Electrochromic Cell

- Sn02 layer glass: F

electroactive material: non-woven glass veil + ferrocene + 1,1'-diethyl-4,4'-diperchlorate bipyridinium + lithium triflate + bis (2-butoxyethyl) phthalate / 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide

- SnC layered glass> ₂ : F

A solution containing 0.03 mol.L ^-1 ferrocene, 1,1'-diethyl-4,4'-bipyridinium diperchlorate at 0.03 mol.L ^-1 and lithium triflate at 0 was prepared. , 03 mol.L ^-1 in a 20/10 mixture of bis (2-butoxyethyl) phthalate / 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide. The solution was stirred for 30 minutes.

Then proceed as in Example 1 to obtain an electrochromic device whose performance is given in Table 2 below:

Table 2

EXAMPLE 3 Preparation of an Electrochromic Cell

- Sn0 ₂ layer glass: F

electroactive material: non-woven glass of ferrocene glass + 1,1'-diethyl-4,4-bipyridinium diperchlorate + lithium triflate + propylene carbonate

- Sn0 ₂ layer glass: F A solution of propylene carbonate containing 0.03 mol.L ^-1 ferrocene, 1,1'-diethyl-4,4'-bipyridinium diperchlorate at 0.03 mol.L ^-1 and triflate was prepared. of lithium at 0.10 mol.L ^-1 . The solution was stirred for 30 minutes.

This solution was impregnated with a non-woven glass web, obtained by dry process, of a thickness of about 400 μm, having glass fibers of E 13 μm thick.

The impregnated web was extended on a "K-glass ™" glass substrate on the electroconductive layer side. Double-sided adhesive strips were placed around the periphery and then covered with a second "K-glass ™" glass substrate, on the electroconductive layer side facing the impregnated web. The electrochromic device thus manufactured, whose active surface area is 29 × 18.5 cm ^2, was calendered.

The performances of this electrochromic device are given in Table 3 below:

Table 3

TL L * a * b * Time of

commutation

Colored condition 4.5 25, 4 8, 7 -52, 0 Approx. 80s for 1.5V staining

Discolored state in 70, 7 87.3 -3, 7 14.2 About 90s for short circuit discoloration EXAMPLE 4 Preparation of an Electrochromic Cell

- SnC layered glass> 2: F

electroactive material: non-woven web of polypropylene fibers + ferrocene + 1,1'-diethyl-4,4'-bipyridinium diperchlorate + lithium triflate + propylene carbonate

SnC layer glass> 2: F A propylene carbonate solution containing 0.03 mol.LT ¹ ferrocene, 1,4-diethyl-4,4'-bipyridinium diperchlorate, was prepared at 0.degree. 03 mol.LT ¹ and lithium triflate at 0.10 mol.LT ¹ . The solution was stirred for 30 minutes.

This solution was impregnated with a nonwoven web of polypropylene fiber at 45 g / m ² of thickness approximately 350 μm.

The performances of this electrochromic device are given in Table 4 below: Table 4

EXAMPLE 5 Choice of solubilization liquid

In order to reduce the fuzziness of the electrochromic panes whose electroactive material is based on nonwoven glass veil, the veil samples of Example 3 were impregnated in different high-index liquids before being encapsulated between two glasses. Table 5 below shows the Light Transmission Measurements: Total Light Transmission (Minolta); and

Diffusion light transmission and blur. 5

Table 5

Meter - »Minolta Hazemeter

TL Tt Td Blur

Liquid Index

% (%) (%) (%)

Carbonate

1, 422 83, 8 65, 9 78.6 propylene

Phthalate

1,515 88.2 88.2 1, 7 1,9 dimethyl

Dibenzoate

poly (ethylene 1,528 88.1 88.4 8.2 9.3 glycol)

Dibenzoate

di (propylene 1.528 88, 877, 9 9.01 10.3 glycol)

Dibenzoate

di (ethylene 1,544 87.5 87, 9 15.30 17.4 glycol)

Claims

1 - Electroactive material for an electrically controllable device with variable optical / energy properties, said material being in the form of a self-supporting layer and comprising or consisting of a matrix which is capable of ensuring the mechanical strength of said electroactive material and in which is inserted an electroactive system formed by:

at least one of said electroactive organic compounds (eai ⁺ and ea ₂ ) being electrochromic to obtain a color contrast; and

ionic charges capable of allowing, under the action of an electric current, oxidation and reduction reactions of said electroactive organic compounds (ea and ea ₂ ), which are necessary to obtain the color contrast;

said electroactive compounds (ea et ea ₂ ) and said ionic charges being within said matrix in the solubilized state by a solubilizing liquid (L), which is also able to solubilize the reduced and oxidized species (eai & ea _2). ⁺ ) respectively associated with said electroactive compounds (ea & ea ₂ );

said matrix being further selected to provide the percolation path to said ionic charges;

characterized in that the matrix is based on a textile web (NT) or a stack of webs including least one textile web (NT), said textile web (NT) or said stack being translucent or transparent (e) once impregnated (e) by the liquid (L) having solubilized said electroactive compounds (ea & ea ₂ ) and the charges ionic, and being able to retain at least part of its integrity once impregnated (e) by the liquid (L) so that the holding of said electroactive material is ensured.

2 - electroactive material according to claim 1, characterized in that the textile web (NT) or a textile web (NT) has a nonwoven or matte web architecture, woven or knit, this nonwoven or matte web, this woven or knit being optionally coated with a binder, which may be at least partially soluble in the liquid (L) to form a gel.

3 - electroactive material according to one of claims 1 and 2, characterized in that each textile web (NT) is composed of one or more types of fibers or son, the son being defined as assemblies of several fibers.

4 - electroactive material according to one of claims 1 to 3, characterized in that the textile web (NT) or a textile web (NT) is based on synthetic fibers and / or yarns, chosen especially from fibers and / or or polyolefin yarns such as polypropylene (PP), polyester, fluoropolymer such as polytetrafluoroethylene (PTFE) or fluorinated polyvinylidene (PVDF), polyamide or polyimide; and / or based on mineral fibers such as glass fibers, and / or based on natural fibers and / or yarns, such as fibers and / or cotton or wool yarns.

5 - electroactive material according to one of claims 1 to 3, characterized in that the textile web (NT) or a textile web (NT) is fiber-based and / or son insoluble in the solubilizing liquid (L) and fibers and / or son soluble in the solubilizing liquid (L), the fibers and / or son thus solubilized having led to the formation of a gel, the quantity fibers and / or insoluble son relative to the amount of fibers and / or soluble son being chosen so that the mechanical strength of the electroactive material is ensured.

6 - electroactive material according to one of claims 1 to 3, characterized in that the textile web (NT) or a textile web (NT) of the stack is a textile web coated with a soluble material in the liquid of solubilization (L) or capable of giving a gel during the impregnation of the textile web or the stack of webs by the solubilization liquid (L).

7 - electroactive material according to one of claims 1 to 6, characterized in that the solubilizing liquid (L) further contains at least one thickening agent which will solubilize in said liquid (L) so as to form a gel.

8 - electroactive material according to one of claims 1 to 7, characterized in that the matrix is formed by a stack of layers, said stack comprising, apart from the textile web or (NT) at least partly insoluble in the liquid (L), at least one non-textile web (NNT) into which the solubilization liquid has penetrated to inflate or solubilize it, and / or at least one textile web (NT ') soluble in the liquid (L ).

9 - electroactive material according to claim 8, characterized in that the polymer constituting at least one polymeric web of the matrix is a homo- or copolymer in the form of a non-porous film but capable of swelling in said liquid, or presenting in the form of a porous film, said porous film possibly being able to swell in the liquid containing ionic charges and whose porosity after swelling is chosen to allow the percolation of the ionic charges in the thickness of the film impregnated with liquid.

10 - Electroactive material according to one of claims 1 to 9, characterized in that the materials constituting the matrix and the solubilization liquid (L) have substantially equal indices, with a difference of at most 0.10, or not more than 0.05.

11 - Process for manufacturing an electroactive material as defined in one of claims 1 to 10, characterized in that the impregnation of said matrix consisting of at least one textile web (NT) is carried out by the solubilizing liquid (L) having solubilized said electroactive system, and is then optionally carried out a dewatering.

12 - Electrically controllable device with variable optical / energy properties, comprising the following stack of layers:

a first glass-function substrate (VI);

an electroactive material;

a second glass-function substrate (V2),

characterized in that the electroactive material is as defined in one of claims 1 to 10.

13 - Single or multiple glazing characterized in that it comprises an electrically controllable device as defined in claim 12.