Photopolymerisable adhesive composition for encapsulating electronic or optoelectronic devices

Abstract

The invention relates to a photopolymerisable adhesive composition comprising, by weight relative to the total weight of the photopolymerisable adhesive composition, at least one block copolymer, preferably a (meth)acrylic block copolymer; at least one (meth)acrylate monomer, the homopolymer of which, obtained after polymerisation, has a glass transition temperature (Tg) of at least 85°C; at least one (meth)acrylate alkoxysilane monomer; from 1 to 15% by weight of a filler chosen from a zeolite or an organically modified clay, or a mixture of zeolite and organically modified clay; and at least one photoinitiator.

Description

[0001] PHOTOPOLYMERIZABLE ADHESIVE COMPOSITION FOR ENCAPSULATING ELECTRONIC OR OPTOELECTRONIC DEVICES

[0002] Field of invention

[0003] The present invention relates to adhesive photopolymerizable compositions for use in encapsulating electronic and optoelectronic devices, particularly flexible electronic and optoelectronic devices, for example organic photovoltaic cells, to protect them against gas and moisture permeation.

[0004] Technical background

[0005] There are different types of electronic or optoelectronic devices, including rigid or flexible electronic or optoelectronic devices. Rigid electronic or optoelectronic devices can be of different natures depending on the applications considered, such as display applications (e.g. OLEDs and QLEDs), photovoltaics (e.g. silicon-based semiconductors, CIGS, CDTE, organic semiconductors, Perovskite-type semiconductors) or sensors.

[0006] Flexible electronic or optoelectronic devices can be defined according to the same application examples but for semiconductor technologies compatible with the use of flexible substrates such as organic light-emitting diode (OLED) devices, organic photovoltaic (OPV) cells, amorphous silicon (a-Si) cells, CIGS, perovskite semiconductors, organic transistors (OFET) or organic sensors using organic semiconductors.

[0007] Electronic or optoelectronic devices are sensitive to multiple factors, for example light, heat, oxygen (air), humidity, pressure, shocks, etc. In order to ensure optimal efficiency and performance and to obtain satisfactory durability, it is therefore necessary to protect and isolate them from their environment. This protection must be all the more effective as the constituent materials are sensitive to the atmosphere, in particular to water and oxygen. This is particularly the case when using organic semiconductors, for example perovskite semiconductors or CIGS semiconductors.

[0008] Various encapsulation techniques have been implemented. These generally include coating the device with an adhesive composition to obtain a coated device, then laminating the coated device between two caps to obtain an encapsulated device. The choice of adhesive composition and caps will depend on the devices to be encapsulated. In addition, depending on the composition and caps used, the electronic or optoelectronic modules obtained will have specific properties, in particular in terms of weight, thickness, transparency / opacity, rigidity / flexibility, gas and liquid permeation / tightness, impact resistance and / or durability / aging.

[0009] Considering the layered arrangement, two types of permeation can be observed, an orthogonal permeation at the external surface of the covers between which the coated devices are interposed, and a lateral permeation at the free edge of the adhesive within the coating material as well as at the interface of the two covers.

[0010] The protection of the device against lateral permeation is ensured in particular by the adhesive or coating material, the effectiveness of which may depend on various factors, in particular its chemical formulation, its application process, its thickness (proportional to the exchange surface with the environment), its interface with the covers, its resistance to usage constraints, etc. The properties of the adhesive must therefore be optimized to minimize or even eliminate lateral permeation, to ensure optimal efficiency and performance and to obtain satisfactory durability.

[0011] Flexible photovoltaic cells (e.g. organic, perovskite, CIGS, CDTE) represent a particularly attractive alternative to rigid silicon-based photovoltaic cells, as they can be manufactured using continuous, high-speed processes (roll-to-roll) and can be suitable for applications requiring flexibility, conformability, or low weight. They are also less fragile (use of flexible covers) and less susceptible to breakage.

[0012] Flexible photovoltaic cells can for example be obtained by low temperature printing of a thin active layer (organic material or perovskite having semiconducting properties) deposited on a flexible polymeric support substrate. The encapsulation of a flexible electronic or optoelectronic device can be carried out by means of a cover with low permeability to gases, in particular to water vapor and oxygen, which must be at least as flexible as the device it protects so as not to become a factor limiting the bending of the latter, or it must have controlled flexibility when, for example, encapsulation is used to knowingly limit the radius of curvature of the device and to avoid its damage.

[0013] There is therefore a real need to provide an adhesive composition allowing the production of electronic or optoelectronic modules having satisfactory properties, in particular satisfactory adhesive, optical, thermal, electrical, gas and moisture barrier, elastic and resistance properties. There is also a need to provide an adhesive composition suitable for the encapsulation of flexible electronic or optoelectronic devices. There is also a need to provide an adhesive composition allowing the production of electronic or optoelectronic modules exhibiting photoaging (for example yellowing) limited over time.There is also a need to provide an adhesive composition for obtaining electronic or optoelectronic modules having limited lateral permeation to gases and water over time while maintaining good light transmission in the electronic or optoelectronic device. There is also a need to provide an adhesive composition for obtaining electronic or optoelectronic modules ensuring optimum efficiency and performance and having satisfactory durability.

[0014] Summary of the invention

[0015] The present application relates firstly to a photopolymerizable adhesive composition comprising, by weight per total weight of the photopolymerizable adhesive composition: at least one block copolymer, preferably a (meth)acrylic block copolymer; at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C; at least one alkoxysilane (meth)acrylate monomer; from 1 to 15% by weight of a filler chosen from a zeolite or an organically modified clay, or a mixture of zeolite and organically modified clay; and at least one photoinitiator. Preferably, the composition of the invention comprises, by weight per total weight of the adhesive photopolymerizable composition: from 10 to 60%, preferably from 10 to 50%, preferably from 20 to 40%, preferably from 20 to 35%, more preferably from 25 to 35%, of at least one block copolymer, preferably a (meth)acrylic block copolymer;from 30 to 80%, preferably from 40 to 75%, preferably from 45 to 75%, preferably from 45 to 60%, more preferably from 45 to 55%, of at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C; from 1 to 20%, preferably from 2 to 15%, preferably from 3 to 10%, preferably from 4 to 6%, of at least one alkoxysilane (meth)acrylate monomer; from 1 to 15%, preferably 1 to 12%, preferably 1 to 10%, preferably from 1.5 to 10%, by weight of a filler chosen from a zeolite or an organically modified clay, or a mixture of zeolite and organically modified clay; and from 0.1 to 5%, preferably from 0.5 to 4, preferably from 1 to 3.5%, preferably from 1 to 3% of at least one photoinitiator.;

[0016] Preferably, in the composition according to the invention, the filler is:

[0017] - a type A zeolite, preferably 3A or 4A;

[0018] - an organically modified clay chosen from:

[0019] - an organically modified clay with quaternary ammonium ions of the type N+RiFbRsF, sulfonium ions of the type S + RIR2RS, phosphonium P ions + RIR2RSR4, R1 to R4 being the same or different and representing hydrogen, a substituted or unsubstituted C1-C25 alkyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted benzyl group, a substituted or unsubstituted carboxyalkyl group, a substituted or unsubstituted acyl group, a substituted or unsubstituted silane group, or mixtures of such clays, preferably a clay organically modified with quaternary ammonium ions of type I R1R2R3R4;

[0020] - a mixture of said zeolite and said organically modified clay. In one embodiment, the block copolymer is chosen from the group consisting of block copolymers comprising at least one block M and at least one block B; said block M designating a polymer block comprising at least 50% by weight of methyl methacrylate; and block B designating an elastomeric polymer block incompatible with block M, and whose glass transition temperature (Tg) is less than 20°C.

[0021] In one embodiment, the alkoxysilane (meth)acrylate monomer is selected from the group consisting of trialkoxysilane (meth)acrylate monomers.

[0022] In one embodiment, the adhesive photopolymerizable composition of the invention further comprises at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of less than 0°C, a methacrylic acid monomer, at least one urethane (meth)acrylate oligomer, at least one monofunctional reactive diluent and mixtures thereof. Preferably, the (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of less than 0°C, if present, is selected from the group consisting of butyl acrylate, ethyl acrylate, propyl acrylate, hexyl acrylate, octyl acrylate, dodecyl acrylate, isopropyl acrylate, isobutyl acrylate, isodecyl acrylate, 2-ethylhexyl acrylate, 2-propylheptyl acrylate, isodecyl methacrylate, dodecyl methacrylate, 2-hydroxyethyl acrylate and mixtures thereof.

[0023] In one embodiment, the composition is a single-component composition.

[0024] Preferably, the adhesive photopolymerizable composition according to the invention has a glass transition temperature after polymerization of at least 85°C, preferably at least 90°C, more preferably at least 100°C.

[0025] The present application also relates to an adhesive product comprising the photopolymerizable adhesive composition according to the invention and an opaque container containing it.

[0026] The present application also relates to an adhesive obtained by the process comprising the following steps: application of a photopolymerizable adhesive composition according to the invention to at least one cover and / or one electronic or optoelectronic device; photopolymerization of the applied photopolymerizable adhesive composition to obtain a polymerized adhesive; and optionally shaping of the polymerized adhesive.

[0027] The present application also relates to an electronic or optoelectronic module comprising the assembly of a series of layers comprising, in this order: a first cover; a first adhesive according to the invention or obtained from the photopolymerizable adhesive composition according to the invention; a flexible electronic or optoelectronic device; a second adhesive according to the invention or obtained from the photopolymerizable adhesive composition according to the invention; and a second cover.

[0028] Preferably, the electronic or optoelectronic module according to the invention is such that the flexible electronic or optoelectronic device is chosen from organic light-emitting diodes, organic photovoltaic cells, organic transistors, or organic sensors, or a combination of these devices.

[0029] Preferably, the electronic or optoelectronic module according to the invention is such that the flexible electronic or optoelectronic device is a perovskite type device.

[0030] The present application also relates to a method for obtaining the module according to the invention, the method comprising the following steps: providing an electronic or optoelectronic device; providing an adhesive photopolymerizable composition according to the invention; providing a first cover; providing a second cover; applying layers of adhesive photopolymerizable composition to the surface of the device and / or to respective internal surfaces of the first and second covers; laminating the device and the layers of adhesive photopolymerizable composition between the respective internal surfaces of the first and second covers; and photopolymerizing the layers of adhesive photopolymerizable composition.

[0031] The present application also relates to the use of the adhesive photopolymerizable composition according to the invention, or of the adhesive according to the invention, for the encapsulation of flexible electronic or optoelectronic devices.

[0032] Description of figures

[0033] Figure 1 represents the evolution of the average active surface area as a function of time for the compositions Cref, Cl and C2.

[0034] Figure 2 represents the evolution of the average thickness of the active surface as a function of time for the compositions Cref, Cl and C2.

[0035] Figure 3 represents the VA for the compositions Cref, Cl and C2.

[0036] Figure 4 represents the VE for the compositions Cref, Cl and C2.

[0037] Figure 5 represents the DA12 for the compositions Cref, Cl and C2.

[0038] Figure 6 represents the DE380 for the compositions Cref, Cl and C2.

[0039] Figure 7 shows the evolution of the average active surface area as a function of time for compositions Cref, C2, C3 and C4.

[0040] Figure 8 represents the evolution of the average thickness of the active surface as a function of time for the compositions Cref, C2, C3 and C4.

[0041] Figure 9 represents the VA for compositions Cref, C2, C3 and C4.

[0042] Figure 10 represents the VE for compositions Cref, C2, C3 and C4.

[0043] Figure 11 represents the DA12 for the compositions Cref, C2, C3 and C4.

[0044] Figure 12 represents the DE380 for compositions Cref, C2, C3 and C4.

[0045] Figure 13 shows the evolution of the average active surface area as a function of time for compositions C5, C3, C6 and C7.

[0046] Figure 14 represents the evolution of the average thickness of the active surface as a function of time for compositions C5, C3, C6 and C7.

[0047] Detailed description

[0048] The invention is now described in more detail and in a non-limiting manner in the following description.

[0049] Unless otherwise stated, all percentages are by mass. In this text, the quantities indicated for a given species may apply to that species according to all its definitions (as mentioned in this text), including the more restricted definitions.

[0050] The invention is now described in more detail and in a non-limiting manner in the following description.

[0051] By "flexible" or "soft" we mean the ability of a material, in particular due to its intrinsic properties and / or its low thickness, to bend, curve and / or fold easily.

[0052] “Flexible electronic or optoelectronic device” (and the module obtained from it) means a device (a module) retaining its electronic conductive or semiconductive properties even when bent with a very small radius of curvature without risk of buckling or delamination of the electronic components.

[0053] By "adhesive" is meant the matrix / structure formed around the electronic or optoelectronic device by the photopolymerized adhesive composition. The terms "adhesive" or "encapsulant" are currently used interchangeably.

[0054] By “module” we mean the assembly of the electronic or optoelectronic device coated with the polymerized adhesive composition and inserted between the two covers.

[0055] The term "cover" refers to the elements between which the coated electronic or optoelectronic device is laminated. Currently, this element may be referred to interchangeably as "support", "plate" or "sheet".

[0056] By "photopolymerizable composition" or "photocrosslinkable composition" is meant a composition for which the initiation (starting) of polymerization is triggered by exposure to electromagnetic radiation, in particular ultraviolet (UV) radiation.

[0057] By "photopolymerizable adhesive composition" is advantageously meant a composition developing adhesive properties when it is subjected to electromagnetic radiation, in particular to ultraviolet (UV) radiation, which initiates (starts) the polymerization thereof.

[0058] A "monomer" means a molecule that can undergo polymerization. When the term "monomer" is used to refer to a constituent of a polymer, it means the unit (or residue) derived from the monomer - or monomer unit / monomer unit - by polymerization with at least one other monomer. "Polymerization" means a process of transforming a single type of monomer or a mixture of different types of monomers into a polymer.

[0059] By "polymer" we mean a copolymer or a homopolymer.

[0060] By "homopolymer" we mean a polymer grouping together several identical monomer units.

[0061] By "copolymer" we mean a polymer grouping together at least two different types of monomer units (called co-monomers).

[0062] By "oligomer" is meant a small polymer compound, obtained by polymerization of 2 to 30 monomers (comprising from 2 to 30 monomer units), i.e. whose degree of polymerization is between 2 and 30.

[0063] A "block copolymer" means a polymer comprising one or more uninterrupted sequences of each of the distinct polymer species, the polymer sequences being chemically different from each other and being linked together by a covalent bond. These polymer sequences are also referred to as polymer blocks.

[0064] By "(meth)acrylic" (or "(meth)acrylate") is meant any type of acrylic and / or methacrylic (or acrylate and / or methacrylate) compound, polymer, monomer or oligomer. For example, (meth)acrylic acid means acrylic acid or methacrylic acid, isobornyl (meth)acrylate means isobornyl acrylate or isobornyl methacrylate, etc.

[0065] Polymerization is a chemical process that binds molecules together to form a three-dimensional network.

[0066] By "initiator" or "primer" is meant a chemical species that reacts with a monomer to form an intermediate compound capable of successfully bonding with a large number of other monomers to form a polymer or that reacts with polymers to initiate the process of molecular interconnection known as polymerization.

[0067] The term "Tg" refers to the glass transition temperature of the polymer material. The glass transition temperature can be measured by differential scanning calorimetry (DSC), for example using the tangent at half height method measured between two inflection points between 40 and 140°C, during the 3 èmeheating cycle. In the context of the present invention, certain monomers are described by the Tg that the homopolymers obtained after polymerization of said monomers would have. In this case, the Tg is measured in the following manner: the monomer is polymerized until maximum conversion thus forming the homopolymer, the measurement of the Tg of the resulting homopolymer is carried out by DSC as mentioned above. By "room temperature" is meant a temperature of approximately 20°C.

[0068] By "substantially free of" is meant a composition comprising less than 1%, preferably less than 0.1%, preferably less than 0.01%, preferably about 0%, of a compound, by weight per total weight of the composition.

[0069] Photopolymerizable adhesive composition

[0070] In a first aspect, the present invention relates to a photopolymerizable adhesive composition.

[0071] Block copolymer

[0072] The composition comprises at least one block copolymer, preferably at least one (meth)acrylic block copolymer.

[0073] The composition may comprise from 10 to 60%, preferably from 10 to 50%, preferably from 20 to 40%, preferentially from 20 to 35%, even more preferentially from 25 to 35%, of at least one block copolymer, by weight per total weight of the composition.

[0074] By "(meth)acrylic block copolymer" is meant a (meth)acrylic block copolymer comprising 10% or less (e.g. 0.1 to 10%), preferably 5% or less (e.g. 0.1 to 5%), of at least one non-(meth)acrylic monomer, by weight per total weight of the copolymer. The non-(meth)acrylic monomer may be selected from the group consisting of butadiene, isoprene, styrene, vinylnaphthalene, a cyclosiloxane monomer, vinylpyridine and their derivatives (e.g. α-methylstyrene or tert-butylstyrene).

[0075] The block copolymer may be chosen from block copolymers comprising at least one block M and at least one block B, in particular block copolymers having the diblock structure BM (or diblock copolymer BM) or the triblock structure MBM (or triblock copolymer MBM), in which each block is connected to the other by means of a covalent bond or an intermediate molecule connected to one of the blocks by a covalent bond and to the other block by another covalent bond. The block copolymer is preferably a triblock copolymer MB-M.

[0076] The M block denotes a polymer block comprising at least 50% by weight of methyl methacrylate. The M block may denote a homopolymer block of polymethyl methacrylate (PMMA - 100% by weight of methyl methacrylate) or a copolymer block comprising at least 50% by weight of methyl methacrylate and 50% or less of another monomer, other than methyl methacrylate, by weight per total weight of the M block.

[0077] Block B designates an elastomeric polymer block incompatible with block M, and whose glass transition temperature (Tg) is lower than room temperature, preferably lower than 0°C, preferably lower than -20°C.

[0078] With respect to the diblock copolymer BM, the block M may consist of methyl methacrylate monomers. Alternatively, the block M may comprise at least 50% (e.g., 50 to 99.9%), preferably at least 75% (e.g., 75 to 99.9%), of methyl methacrylate; and 50% or less (e.g., 0.1 to 25%), preferably 25% or less (e.g., 0.1 to 25%), of at least one other monomer other than methyl methacrylate, by weight per total weight of the block M.

[0079] The other monomer, other than methyl methacrylate, constituting the M block, may be another (meth)acrylic monomer or a non-(meth)acrylic monomer.

[0080] The non-(meth)acrylic monomer may be selected from the group consisting of butadiene, isoprene, styrene, vinylnaphthalene, a cyclosiloxane monomer, vinylpyridine and their derivatives (e.g. α-methylstyrene or tert-butylstyrene).

[0081] The other (meth)acrylic monomer may be selected from the group consisting of methyl acrylate, ethyl (meth)acrylate, (meth)acrylic acid, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, amides derived from (meth)acrylic acid (e.g., N,N-dimethylacrylamide), 2-methoxyethyl (meth)acrylate, 2-aminoethyl (meth)acrylate, polyethylene glycol (PEG) (meth)acrylate, wherein the PEG group has a molar mass ranging from 400 to 10,000 g / mol, and mixtures thereof.

[0082] The elastomeric B-block may consist of alkyl (meth)acrylate monomer. Alternatively, the B-block may comprise at least 95% (e.g., 95 to 99.9%) of alkyl (meth)acrylate; and 5% or less (e.g., 0.1 to 5%) of another monomer other than alkyl (meth)acrylate, by weight per total weight of the B-block.

[0083] The alkyl (meth)acrylate may be chosen from the group consisting of ethyl acrylate (Tg of the homopolymer obtained after polymerization = -24°C), butyl acrylate (Tg of the homopolymer obtained after polymerization = -54°C), 2-ethylhexyl acrylate (Tg of the homopolymer obtained after polymerization = -85°C), hydroxyethyl acrylate (Tg of the homopolymer obtained after polymerization = -15°C), 2-ethylhexyl methacrylate (Tg of the homopolymer obtained after polymerization = -10°C) and mixtures thereof; preferably the alkyl (meth)acrylate is butyl acrylate.

[0084] The other monomer, other than alkyl (meth)acrylate, may be selected from the group consisting of butadiene, isoprene, styrene, vinylnaphthalene, a cyclosiloxane monomer, vinylpyridine and their derivatives (e.g. α-methylstyrene or tert-butylstyrene).

[0085] The BM diblock copolymer may have a number-average molar mass of between 10,000 and 500,000 g / mol, preferably between 20,000 and 200,000 g / mol.

[0086] The diblock copolymer BM may comprise a mass fraction (by weight per total weight of the copolymer) of between 5 and 95%, preferably between 15 and 85%, in block M; and between 5 and 95%, preferably between 15 and 85%, in block B.

[0087] In the case of the MBM triblock copolymer, the two M blocks are made up of the same monomers (or comonomers) as the M block of the BM diblock copolymer as described above. These two M blocks may be identical or different. For example, these two M blocks may be different in molar mass, but be made up of the same monomers.

[0088] The B block consists of the same monomers (or co-monomers) as the B block of the BM diblock copolymer as described above.

[0089] The MBM triblock copolymer may have a number-average molar mass of between 10,000 g / mol and 500,000 g / mol, preferably between 20,000 and 200,000 g / mol.

[0090] The MBM triblock copolymer may comprise a mass fraction (by weight per total weight of the copolymer) of between 10 and 80%, preferably between 15 and 70%, preferably between 40 and 60%, in M ​​blocks; and between 20 and 90%, preferably between 30 and 85%, preferably between 40 and 60%, in B block.

[0091] Preferably, the MBM triblock copolymer is a polymethylmethacrylate-poly(styrene-co-butylacrylate)-polymethylmethacrylate block copolymer.

[0092] Block copolymers may be manufactured by controlled radical polymerization (CRP), for example according to the methods as described in PCT applications WO 96 / 24620 A and WO 00 / 71501 A1, or by anionic polymerization.

[0093] One or less of the M and B blocks may be functionalized by means of one or more functions selected from the group consisting of acid, amine, amide, epoxy, thiol functions, quaternary ammonium groups, chlorinated groups and fluorinated groups. The block copolymers are commercially available under the name Nanostrength® from Arkema.

[0094] The composition of the invention comprises from 1 to 15%, preferably from 1 to 12%, preferentially from 1 to 10%, preferentially from 1.5 to 10%, by weight of a filler chosen from a zeolite or an organically modified clay, or a mixture of zeolite and organically modified clay, relative to the total weight of the composition.

[0095] Organically modified clay

[0096] The clay can be chosen from phyllosilicates, ionosilicates, nesosilicates, sorosilicates, cyclosilicates, tectosilicates, and mixtures thereof. These clays typically have a layered structure, and contain in the native state (not organically modified) between the layers alkali cations such as K + and Na + or alkaline earth.

[0097] Preferably, the clay is chosen from phyllosilicates.

[0098] Among the phyllosilicates, we can cite, for example, montmorillonite, vermiculite and kaolinite.

[0099] Preferably, the clay is a montmorillonite.

[0100] In the context of the invention, an “organically modified clay”, or “modified organophilic clay”, typically results from the exchange of alkali or alkaline-earth ions present in the galleries separating the clay layers by organic cations such as, for example, quaternary ammonium, sulfonium or phosphonium cations. These modified clays typically have a layered structure, and contain between the layers organic cations such as alkylammonium ions, and / or alkylphosphonium ions, and / or alkylsulfonium ions obtained by an ion exchange reaction with alkali cations or alkaline-earth cations in the native state.

[0101] The organically modified clay may be an organically modified phyllosilicate, an organically modified ionosilicate, an organically modified nesosilicate, an organically modified sorosilicate, an organically modified cyclosilicate, an organically modified tectosilicate, or mixtures thereof.

[0102] Preferably, the organically modified clay is chosen from organically modified phyllosilicates, and even more preferably from organically modified montmorillonites.

[0103] The organically modified clay is preferably chosen from clays organically modified by quaternary ammonium ions of the type IXTRiFbRsF, sulfonium ions of the type S + RIR2RS, phosphonium P ions +RIR2RSR4, R1 to R4 being identical or different and representing hydrogen; a substituted or unsubstituted C1-C25 alkyl group, as an example of a substituted alkyl group, mention may be made of dimethyldialkyl(C14-C18)amine, octadecylamine; a substituted or unsubstituted phenyl group, a substituted or unsubstituted benzyl group; a substituted or unsubstituted carboxyalkyl group, a substituted or unsubstituted acyl group; a substituted or unsubstituted silane group, for example an aminopropyltriethoxysilane group, an octasilane group; or mixtures of such clays.

[0104] Preferably, the organically modified clay is a montmorillonite organically modified with quaternary ammonium ions of type I R1R2R3R4, R1 to R4 being the same or different and representing hydrogen; a substituted or unsubstituted C1-C25 alkyl group, as an example of a substituted alkyl group, mention may be made of dimethyldialkyl(C14-C18)amine, octadecylamine; a substituted or unsubstituted phenyl group, a substituted or unsubstituted benzyl group; a substituted or unsubstituted carboxyalkyl group; a substituted or unsubstituted acyl group; a substituted or unsubstituted silane group, for example an aminopropyltriethoxysilane group, an octasilane group; or mixtures of such clays.

[0105] Preferably, the organically modified clay is a montmorillonite organically modified by quaternary ammonium ions of the N type. +RIR2RSR4, R1 to R4 being identical or different, and representing hydrogen; a substituted or unsubstituted benzyl group; a substituted or unsubstituted C1-C10 alkyl group or a substituted C1-C25 alkyl group such as, for example, dimethyldialkyl(C14-C18)amine, octadecylamine; a substituted or unsubstituted carboxyalkyl group; a substituted or unsubstituted silane group, for example an aminopropyltriethoxysilane group, an octasilane group.

[0106] Examples of organically modified clays include clays marketed by Southern Clay Products under the name Cloisite® (such as Cloisite®C10A, Cloisite®C15, Cloisite®C14-C18A), or those marketed by Nanocore under the name Nanomer®, for example Nanoclay Nanomer®l.44P or Nanoclay Nanomer®l.31PS.

[0107] Zeolites

[0108] The zeolitic adsorbents, or more simply the zeolites, which can be used in the context of the present invention can be of any type known to those skilled in the art.

[0109] Zeolites are typically crystalline, porous aluminosilicate compounds that possess a three-dimensional crystalline structure consisting of an assembly of SiO4 and AlO4 tetrahedra linked together by the sharing of one or more oxygen atoms. These compounds thus form crystalline networks containing nanometric pores. These structures generally contain cations to make the system electrically neutral, these cations being most often sodium, potassium or calcium cations, but also barium, rare earths or mixtures of two or more of these cations in any proportion.

[0110] The zeolite can be chosen from zeolite A type zeolites, faujasite type zeolites (X, MSX and LSX (for “Low silica X”), Y) of CHA type (Chabazite), of HEU type (Clinoptilolite), and their mixtures.

[0111] The structure and properties of zeolite A are well known and extensively described in the literature, notably in the work of Donald W. Breck, "Zeolite Molecular Sieves", John Wiley and Sons, (1974), pp. 83 et seq., and by the patents of Milton (US 2,882,243) and Barrer (FR 1,257,034).

[0112] The modification of the nature of the cations by exchange of all or part can be accompanied by a variation in the size of the pores or a modification of the selectivity by creation of specific interactions with the adsorbed molecules and thus change the adsorption properties.

[0113] Thus, with zeolite A, which, in sodium form after synthesis, has a pore opening of 4 Å (hence its frequent name of "zeolite 4A"), it is possible to carry out various cationic exchanges in order to give it the desired properties. Frequently, these are alkali or alkaline-earth cations such as Lithium (Li + ), Potassium (K + ), Cesium (Cs + ), Magnesium (Mg 2+ ), Calcium (Ca 2+ ), Strontium (Sr 2+ ), Barium (Ba 2+ ), Cerium (Ce 3+ ), or other cations such as those of rare earths or metals, for example Lanthanum (La2+ / La3+), Silver (Ag+), Copper (Cu 2+ ), Nickel (Ni 2+ ), Zinc (Zn 2+ ), Iron (Fe 2+ , Fe 3+ ), Chromium (Cr 2+ to Cr 6+), and others. Thus, depending on the type of cation exchange carried out, zeolite A can for example be transformed either: into the calcium form by exchange with a calcium salt in aqueous solution, in order to obtain a zeolite whose pores have an effective opening of 5 Å (hence its frequent name of "zeolite 5A"). into the potassium form by exchange with a potassium salt in aqueous solution and a zeolite is obtained whose pores have an effective opening of 3 Å (hence its frequent name "zeolite 3A"). into different forms by mixing aqueous solutions of Lithium, Calcium or Potassium salts for example.

[0114] By zeolite 3A, we mean here a type A zeolite of which 20 to 70% (reported in equivalents) of the exchangeable cationic sites are occupied by Potassium ions (K + ), and 30% to 80% are occupied by alkali, alkaline earth, rare earth or metal ions as defined previously.

[0115] By zeolite 4A is meant here an A-type zeolite in which essentially all the exchangeable cationic sites are occupied by Sodium Na cations + (sodium form after synthesis).

[0116] By zeolite 5A is meant here a type A zeolite of which 40% to 100% of the exchangeable cationic sites (reported in equivalents) are occupied by Ca ions 2+ , and 0% to 5% occupied by alkali, alkaline earth, rare earth or metal ions as defined above, for example Sodium Na + , but it would not be outside the scope of the invention if other cations were present as described above.

[0117] Faujasites are a group of mineral species characterized by their crystallographic topographic structure, which are notably described in the work of Donald W. Breck "Zeolite Molecular Sieves", John Wiley and Sons editions, (1974), pp. 92 and following.

[0118] Preferably, the zeolite is a type A zeolite, more preferably type 3A or 4A.

[0119] Even more preferably, the zeolite is a type 3A zeolite.

[0120] The zeolites of the invention may be in the form of powder or agglomerates. Agglomeration means the shaping of the zeolite powder using a mineral and / or organic binder. This shaping of agglomerates may be carried out using any method known to those skilled in the art, such as, for example, extrusion, compaction, agglomeration. For example, the agglomerates may be in the form of platelets, beads of a few nanometers to a few millimeters, spun or extruded materials, bars, rods, or even molded parts of various sizes and shapes, which may be generically called "cores" according to English terminology, and others.

[0121] This shaping can be done by mixing a pasty mixture of zeolite(s) with binder(s) and possibly one or more additives intended, for example, to facilitate the handling of the paste by modifying the rheology and / or the adhesive power. This binder, most often inert, is intended to ensure the cohesion of the zeolite(s) crystals between them.

[0122] Among the mineral binders, it is possible, for example, to use alumina, montmorillonite, atta pulgite, sepiolite, zeolithizable clays, such as those chosen from kaolins, kaolinites, nacrites, dickites, halloysites, metakaolins, colloidal clays, for example of the Attagel type or other natural minerals or zeolites (clinoptilolite, mordenite or chabazite), diatomaceous earth, talc, and other mineral binders known to those skilled in the art, which can be used alone or as a mixture of two or more of them.

[0123] Among the organic binders that can be used alone or in combination with the mineral binders mentioned above, any polymer matrix known per se to those skilled in the art of polymers is understood. It may comprise a thermoplastic and / or thermosetting homopolymer and / or copolymer, for example, and without limitation, polyurethane, fluorinated polymers, such as PVDF, epoxy resins, and others. These polymers can be in any form, and for example in the form of foam, expanded or semi-expanded.

[0124] In addition to the mineral and / or organic binders, one or more additives commonly used and known to those skilled in the art may be added to the zeolites, for example additives chosen from silica, colloidal silica, cellulose, corn starch or any other type of pore-forming agent.

[0125] Zeolites, in agglomerated form, generally have a size distribution giving an average diameter between 0.3 mm and 1.6 mm.

[0126] The granule size distribution is measured by liquid laser granulometry using, for example, a Mastersizer 2000 device.

[0127] The Si / Al atomic ratio of the zeolite is generally between 1.0 and 2.0, preferably between 1.0 and 1.8, more preferably between 1.0 and 1.4.

[0128] The Si / Al atomic ratio of the zeolite can be measured by solid-state silicon 29 NMR if it is a powder or by X-ray fluorescence as described in standard NF EN ISO 12677: 2011 (for example on a wavelength dispersive spectrometer WDXRF) if it is an agglomerate.

[0129] The zeolite may comprise crystals whose number average diameter (D50), measured by scanning electron microscope (SEM) is less than 20 microns, preferably between 0.1 and 19 microns, preferably between 0.5 and 10 microns, and even more preferably between 1 and 5 microns.

[0130] As non-limiting examples of zeolites which may be used in the context of the present invention, mention may be made of those marketed by Arkema under the names Siliporite® H3Ri, Siliporite® NK10, Siliporite® NK30, Siliporite® SA 1720, Siliporite® NK20, Siliporite® G5 XP, those marketed by ZEOCHEM under the names Purmol® 3ST (3A), Purmol® 4ST (A), Zeochem® Z4-01, Zeochem® 4A-8BL, or those marketed by GRACE under the names Sylosiv®, Cryosiv®, or by UOP under the names Molsiv™ 3A, Molsiv™ 4A, Molsiv™ 5A, XH-7™, XH-9™ and XH-11™. In a particularly advantageous embodiment, the filler is a mixture of zeolite and organically modified clay. The inventors have shown that this combination makes it possible to increase the quantity of filler in the composition of the invention without adversely affecting its viscosity and transparency to light.Preferably, this mixture comprises from 30 to 70%, preferably from 40 to 60%, by weight of zeolite and from 70 to 30%, preferably from 60 to 40%, by weight of organically modified clay, relative to the total weight of the zeolite and organically modified clay mixture.

[0131] (Meth)acrylate monomers

[0132] The composition comprises at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C.

[0133] The composition may comprise from 30 to 80%, preferably from 40 to 75%, preferably from 45 to 75%, preferably from 45 to 60%, more preferably from 45 to 55%, of at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C, by weight per total weight of the composition.

[0134] The (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C may be chosen from the group consisting of methyl methacrylate, tert-butyl methacrylate, phenyl methacrylate, isobornyl methacrylate, isobornyl acrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl methacrylate, dihydrodicyclopentadienyl acrylate and mixtures thereof; preferably the (meth)acrylate monomer having a glass transition temperature of at least 85°C is methyl methacrylate.

[0135] The composition according to the invention may comprise a mixture of (meth)acrylate monomers whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C, said mixture may comprise at least one methacrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C and at least 5% by weight of a mono-acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C. Said mixture may further comprise at least one diacrylate monomer. Preferably, said mixture comprises:

[0136] - from 20% to 95% by weight, more preferably from 20% to 80% by weight, and even more preferably from 30% to 70%, preferably from 40 to 60%, by weight relative to the weight of the mixture, of at least one methacrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C and - at least 5%, preferably at least 10%, more preferably from 5 to 80%, more preferably from 20% to 80% even more preferably from 30% to 70%, preferably from 40 to 60% by weight of a mono-acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C. Preferably, the quantity by weight of mono-acrylate monomer in said mixture is such that the viscosity of the adhesive photopolymerizable composition according to the invention obtained has a viscosity of 100 to 20,000 mPa.s, preferably a viscosity of 100 to 10,000 mPa.s.s, preferably from 500 to 5,000 mPa.s, more preferably from 1,000 to 2,500 mPa.s. The viscosity can be measured according to standard NF EN 12092 “Adhesives - Determination of viscosity” using a Brookfield DVIII Ultra viscometer (rotary: SC4-27, rotation: 20 rpm, temperature: 25°C).

[0137] The methacrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of at least 85°C of said mixture may be chosen from the group consisting of methyl methacrylate, tert-butyl methacrylate, phenyl methacrylate, isopropyl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl methacrylate, and mixtures thereof, preferably the methacrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of at least 85°C is methyl methacrylate.

[0138] The mono-acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of at least 85°C of said mixture may be chosen from the group consisting of isobornyl acrylate, dihydrodicyclopentadienyl acrylate, and mixtures thereof, preferably the acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C is isobornyl acrylate.

[0139] Said mixture may further comprise from 0 to 40% by weight, preferably from 0 to 20% by weight or from 1 to 20% by weight, more preferably from 0 to 10% by weight or from 1 to 10% by weight, preferably from 0 to 5% by weight or from 1 to 5% by weight, of at least one diacrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of at least 85°C, in particular dipropylene glycol diacrylate (CAS No. 57472-68-1), neopentyl glycol hydroxypivalate diacrylate (CAS No. 2136366-99-7), tricyclodecanedimethanol diacrylate (CAS No. 52594-17-2), preferably the diacrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of at least 85°C is tricyclodecanedimethanol diacrylate (TCDDMDA). Monomers a

[0140] The composition comprises at least one alkoxysilane monomer

[0141] (meth)acrylate.

[0142] The composition may comprise from 1 to 20%, preferably from 2 to 15%, preferentially from 3 to 10%, preferentially from 4 to 6%, of at least one alkoxysilane (meth)acrylate monomer, by weight per total weight of the composition.

[0143] The alkoxysilane (meth)acrylate monomer, including the alkyl alkoxysilane (meth)acrylate monomer, may be chosen from the group consisting of trialkoxysilane (meth)acrylate monomers; preferably trimethoxysilane (meth)acrylate monomers; preferably the alkoxysilane (meth)acrylate monomer is chosen from the group consisting of 3-(trimethoxysilyl)propyl acrylate, 3-(trimethoxysilyl)propyl methacrylate, trimethoxysilyl acrylate, trimethoxysilyl methacrylate and mixtures thereof; preferably the alkoxysilane (meth)acrylate monomer is 3-(trimethoxysilyl)propyl methacrylate.

[0144] 3-(Trimethoxysilyl)propyl methacrylate is commercially available as Silquest® A174 from Momentive®.

[0145] Photoinitiator

[0146] The composition comprises at least one photoinitiator. Any compound capable of initiating the photopolymerization of the adhesive composition, in particular any compound capable of initiating the radical polymerization of the urethane (meth)acrylate monomers and / or oligomers by ultraviolet (UV) or visible light irradiation, to obtain the adhesive, may be used.

[0147] The composition may comprise from 0.1 to 5%, preferably from 0.5 to

[0148] 4%, preferably from 1 to 3.5%, of at least one photoinitiator, preferably from 1 to 3%, by weight per total weight of the composition.

[0149] The photoinitiator may be selected from the group consisting of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, triethylbenzoyl-diphenylphosphine oxide, thioxanthen-9-one, 4,4-bis(diethylamino)benzophenone, 9,10-phenanthrene quione, benzoyltrimethylgermane, dibenzoyldiethylgermane, bis-(4-methoxybenzoyl)diethylgermanium and mixtures thereof; preferably phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide. One mixture may comprise, for example, benzophenone, α-hydroxyketone and triethylbenzoyl-diphenylphosphine oxide. Another mixture may comprise, for example, benzoyltrimethylgermane, dibenzoyldiethylgermane and bis-(4-methoxybenzoyl)diethylgermanium.

[0150] Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide is commercially available as Omnirad® 819 from IGM Resins (formerly Irgacure® 819 from Ciba® Specialty Chemicals). The mixture comprising benzophenone, α-hydroxyketone and triethylbenzoyl-diphenylphosphine oxide is commercially available as Esacure® KTO 46 from Lehvoss. Other (meth)acrylate monomers

[0151] The composition may comprise at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of less than 0°C. In this embodiment, the composition comprises the mixture of a (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of at least 85°C and a (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of less than 0°C.

[0152] The composition may comprise from 0 to 5% of at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of less than 0°C, by weight per total weight of the composition. If present, the composition may comprise from 0.1 to 5%, preferably from 1 to 5%, preferably from 2 to 4%, of at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of less than 0°C, by weight per total weight of the composition.

[0153] The (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of less than 0°C may be chosen from the group consisting of butyl acrylate, ethyl acrylate, propyl acrylate, hexyl acrylate, octyl acrylate, dodecyl acrylate, isopropyl acrylate, isobutyl acrylate, isodecyl acrylate, 2-ethylhexyl acrylate, 2-propylheptyl acrylate, isodecyl methacrylate, dodecyl methacrylate, 2-hydroxyethyl acrylate and mixtures thereof; preferably butyl acrylate.

[0154] Alternatively, the composition may be substantially free of (meth)acrylate monomers whose homopolymer obtained after polymerization has a glass transition temperature (Tg) below 0°C.

[0155] Methacrylic acid

[0156] The composition may comprise a methacrylic acid monomer.

[0157] The composition may comprise from 0 to 20% of methacrylic acid, by weight per total weight of the composition. If present, the composition comprises from 1 to 16%, preferably from 3 to 12%, from 3 to 10%, preferably from 3.5 to 7%, of methacrylic acid, by weight per total weight of the composition. Oil urethane

[0158] The composition may comprise at least one urethane (meth)acrylate oligomer.

[0159] The composition may comprise from 0 to 7% of at least one urethane (meth)acrylate oligomer, by weight per total weight of the composition. If present, the composition comprises from 0.1 to 7%, preferably from 3 to 6%, of at least one urethane (meth)acrylate oligomer, by weight per total weight of the composition.

[0160] The urethane (meth)acrylate oligomer may be chosen from aliphatic urethane diacrylate oligomers, preferably the urethane (meth)acrylate oligomer is aliphatic urethane diacrylate.

[0161] The composition may further comprise at least one monofunctional reactive diluent.

[0162] The composition may comprise from 0 to 0.7% of at least one monofunctional reactive diluent, by weight per total weight of the composition. If present, the composition comprises from 0.1 to 0.7%, preferably from 0.3 to 0.7%, of at least one monofunctional reactive diluent, by weight per total weight of the composition.

[0163] The monofunctional reactive diluent may be 2-(2-ethoxy-ethoxy) ethyl acrylate. The mixture of a urethane (meth)acrylate oligomer and a monofunctional reactive diluent, consisting of about 90% aliphatic urethane diacrylate and about 10% 2-(2-ethoxy-ethoxy) ethyl acrylate by weight per total weight of the mixture, is commercially available under the name CN966H90® from Sartomer.

[0164] Viscosity

[0165] The photopolymerizable adhesive composition is preferably a liquid composition.

[0166] The composition may have a viscosity of 100 to 20,000 mPa.s, preferably 100 to 10,000 mPa.s, more preferably 500 to 5,000 mPa.s, more preferably 1,000 to 2,500 mPa.s. The viscosity may be measured according to standard NF EN 12092 “Adhesives - Determination of viscosity” using a Brookfield DVIII Ultra viscometer (rotary: SC4-27, rotation: 20 rpm, temperature: 25°C).

[0167] After polymerization, the composition has a glass transition temperature (Tg), preferably of at least 85°C, preferably of at least 90°C, preferably of at least 100°C.

[0168] In particular embodiments, the composition may comprise (alternatively may consist of), by weight per total weight of the composition: from 10 to 60%, preferably from 10 to 50%, preferably from 20 to 40%, preferably from 20 to 35%, more preferably from 25 to 35%, of at least one block copolymer; from 30 to 80%, preferably from 40 to 75%, preferably from 45 to 75%, preferably from 45 to 60%, more preferably from 45 to 55%, of at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of at least 85°C; from 1 to 15%, preferably from 1 to 10%, by weight of a filler chosen from a zeolite or an organically modified clay, or a mixture of zeolite and organically modified clay;

[0169] 1 to 20%, preferably 2 to 15%, preferably 3 to 10%, preferably 4 to 6%, of at least one alkoxysilane (meth)acrylate monomer;

[0170] 0.1 to 5%, preferably 0.5 to 4%, preferably 1 to 3.5%, preferably 1 to 3%, of at least one photoinitiator; 0 to 5%, preferably 0.1 to 5%, of at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature below 0°C; 0 to 20%, preferably 1 to 16%, preferably 3 to 12%, of methacrylic acid; 0 to 7%, preferably 0.1 to 7%, preferably 3 to 6%, of at least one urethane (meth)acrylate oligomer; and 0 to 0.7%, preferably 0.1 to 0.7%, preferably 0.3 to 0.7%, of at least one monofunctional reactive diluent.

[0171] In particular embodiments, the composition may comprise (alternatively may consist of), by weight per total weight of the composition: from 20 to 40%, preferably from 20 to 35%, more preferably from 25 to 35%, of at least one block copolymer; from 45 to 75%, preferably from 45 to 60%, more preferably from 45 to 55%, of at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of at least 85°C; from 1 to 15%, preferably from 1 to 12%, preferably from 1 to 10%, more preferably from 1.5 to 10% by weight of a filler chosen from a zeolite or an organically modified clay, or a mixture of zeolite and organically modified clay; from 3 to 10%, preferably from 4 to 6%, of at least one alkoxysilane (meth)acrylate monomer; from 1 to 3.5%, preferably from 1 to 3%, of at least one photoinitiator; from 1 to 16%, preferably from 3 to 12%, of methacrylic acid.

[0172] In particular embodiments, the composition may comprise (alternatively may consist of), by weight per total weight of the composition: from 20 to 40%, preferably from 20 to 35%, more preferably from 25 to 35%, of at least one (meth)acrylic block copolymer; preferably a (meth)acrylic block copolymer having an MBM triblock structure; from 45 to 75%, preferably from 45 to 60%, more preferably from 45 to 55% of at least one (meth)acrylate monomer, the homopolymer of which is obtained after polymerization at a glass transition temperature of at least 85°C; preferably a monomer chosen from the group consisting of methyl methacrylate, tert-butyl methacrylate, phenyl methacrylate, isobornyl methacrylate, isobornyl acrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl methacrylate, dihydrodicyclopentadienyl acrylate and mixtures thereof;preferably a monomer being methyl methacrylate or a mixture of a mono-acrylate monomer, a methacrylate monomer and a diacrylate monomer, preferably a mixture of a methyl methacrylate monomer, a mono-acrylate monomer chosen from isobornyl acrylate, dihydrodicyclopentadienyl acrylate, preferably isobornyl acrylate, and the diacrylate monomer is chosen from dipropylene glycol diacrylate (CAS No. 57472-68-1), neopentyl glycolhydroxypivalate diacrylate (CAS No. 2136366-99-7), tricyclodecanedimethanol diacrylate, preferably tricyclodecanedimethanol diacrylate (TCDDMDA); preferably from 3 to 10%, preferably from 4 to 6%, of at least one alkoxysilane (meth)acrylate monomer chosen from the group consisting of trialkoxysilane (meth)acrylate monomers; preferably of trimethoxysilane (meth)acrylate monomers;preferably 3-(trimethoxysilyl)propyl acrylate, 3-(trimethoxysilyl)propyl methacrylate, trimethoxysilyl acrylate, trimethoxysilyl methacrylate and mixtures thereof; preferably a monomer being 3-(trimethoxysilyl)propyl methacrylate; from 1 to 15%, preferably from 1 to 12%, preferably from 1 to 10%, preferably from 1.5 to 10%, of a filler chosen from a zeolite or an organically modified clay, or a mixture of zeolite and organically modified clay, the zeolite being a type A zeolite, preferably a type 3A or 4A zeolite, the clay being: a clay organically modified by quaternary ammonium ions of the type N+RiFbRsF, sulfonium ions of the type S; + RIR2RS, phosphonium P ions +RIR2RSR4, R1 to R4 being identical or different and representing hydrogen; a substituted or unsubstituted C1-C25 alkyl group, as an example of a substituted alkyl group, mention may be made of dimethyldialkyl(C14-C18)amine, octadecylamine; a substituted or unsubstituted phenyl group; a substituted or unsubstituted benzyl group, a substituted or unsubstituted carboxyalkyl group; a substituted or unsubstituted acyl group; a substituted or unsubstituted silane group, for example an aminopropyltriethoxysilane group, an octasilane group; or mixtures of such clays, preferably a clay organically modified by quaternary ammonium ions of the type N +RIR2RSR4; from 1 to 3.5%, preferably from 1 to 3% of at least one photoinitiator chosen from the group consisting of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, triethylbenzoyl-diphenylphosphine oxide, thioxanthen-9-one, 4,4-bis(diethylamino)benzophenone, 9,10-phenanthrene quione, benzoyltrimethylgermane, dibenzoyldiethylgermane, bis-(4-methoxybenzoyl)diethylgermanium and mixtures thereof; preferably a photoinitiator being phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide;

[0173] - from 1 to 16%, preferably from 3 to 12%, of methacrylic acid.

[0174] Single-component composition

[0175] Preferably, the composition is a single-component composition, i.e. a ready-to-use composition. Conversely, preferably, the composition is not a multi-component composition, i.e. a kit comprising at least two separately packaged components, which components are intended to be mixed together extemporaneously, just before application of the composition thus obtained.

[0176] A single-component composition does not need to be prepared in the form of at least two separate components, which must be mixed just before use, in order to avoid premature polymerization. Indeed, the single-component composition comprises at least one photoinitiator, allowing polymerization to be initiated as soon as the composition is exposed to light radiation, in particular ultraviolet (UV) radiation. In order to avoid any premature or untimely polymerization, the composition must not be exposed to light. Adhesive product

[0177] In a second aspect, the present invention comprises an adhesive product. The adhesive product comprises the photopolymerizable adhesive composition as described above and an opaque container containing it. By "opaque container" is meant a container whose walls do not allow the passage of light capable of activating the photoinitiator, in particular visible light and ultraviolet radiation (below 600 nm).

[0178] The opaque container may be any container capable of containing the composition and retaining its properties, in particular its adhesive properties. The use of an opaque container makes it possible not to expose the composition to light (in particular to ultraviolet radiation) before use, that is to say during its storage and transport, and thus avoids any premature or untimely polymerization.

[0179] The container may be chosen, for example, from the group consisting of a bottle or a tube.

[0180] Adhesive

[0181] In a third aspect, the present invention relates to an adhesive, in particular an adhesive obtained from the photopolymerizable adhesive composition as described above. By "adhesive" or "photopolymerized adhesive composition" is meant the adhesive layer obtained by applying the photopolymerizable adhesive composition, by photopolymerizing it and optionally by shaping the adhesive thus obtained.

[0182] The adhesive is obtained by the process comprising the following steps: application of the photopolymerizable adhesive composition as described above to at least one cover and / or one electronic or optoelectronic device; photopolymerization of the applied composition to obtain a polymerized adhesive; and optionally shaping of the polymerized adhesive.

[0183] The adhesive can take the form of a film.

[0184] The composition may be applied using a conventional application technique, for example the following techniques: slot-die coating, deep coating, inkjet printing, screen printing, spin coating, spray coating or doctor blade application. The composition may be photopolymerized by exposure to ultraviolet (UV) radiation and visible light, in particular by using a UV lamp emitting in a range that allows the photoinitiator to be activated without being absorbed by the encapsulation cap. A suitable UV lamp may be, for example, a UV source such as the Delolux® 03S UV LED system. Photopolymerization may be carried out for between 1 and 10 minutes.

[0185] The adhesive may have a thickness of 10 to 200 pm, preferably 10 to 100 pm, preferably 10 to 30 pm.

[0186] The adhesive has a number of advantages, particularly for use at a temperature of at least 70°C, preferably at least 85°C, for example when the electronic or optoelectronic device is a photovoltaic cell or when the device must meet temperature test standards (automotive or photovoltaic applications for example).

[0187] Advantageously, the adhesive formulation according to the invention allows use of the encapsulated object up to at least 70°C, or even up to at least 85°C, for example when the electronic or optoelectronic device is a photovoltaic cell or when the device must meet temperature test standards (automotive applications for example).

[0188] The adhesive preferably has satisfactory adhesive properties, in particular to allow satisfactory cohesion between the electronic or optoelectronic device and the covers, even for flexible modules.

[0189] The adhesive preferably has satisfactory optical properties, in particular satisfactory transparency, in particular to allow the transmission of light waves to the electronic or optoelectronic device and / or to limit diffraction, in particular when the device is a photovoltaic cell. The adhesive may have a transparency of 90% in transmission between 400 and 800nm. Transparency can be measured by UV-visible transmission spectrometry.

[0190] The adhesive preferably has satisfactory electrical properties, in particular satisfactory electrical insulation properties, in particular to prevent any short circuit inside the module. Electrical insulation properties can be measured using ASTM D149.

[0191] The adhesive preferably has satisfactory resistance, in particular to aging under ultraviolet radiation, abrasion and / or impact. The adhesive preferably has satisfactory barrier properties, in particular barrier properties to water and oxygen (air). The barrier properties can be measured with the ASTM F1249 standard with a water vapor transmission rate of less than 5 g.nr 2 .j 1 , preferably lower than g.nr 2 .) 1 , for a thickness of 1 mm, at a temperature of 38°C and a relative humidity of 85%.

[0192] The adhesive preferably has satisfactory elastic properties. Elastic properties, particularly flexibility, can be measured using a cylindrical mandrel flex tester, with the three- or four-point bending test method, or with tensile measurements.

[0193] Electronic or optoelectronic module

[0194] In a fourth aspect, the present invention relates to a module, preferably a flexible module. The module corresponds to an encapsulated electronic or optoelectronic device.

[0195] The module may be obtained by superimposing and assembling a series of layers. The series of layers may comprise, in this order: a first cover; a first adhesive as described above or obtained from the photopolymerizable adhesive composition as described above; an electronic or optoelectronic device; a second adhesive as described above or obtained from the photopolymerizable adhesive composition as described above; and a second cover.

[0196] The electronic or optoelectronic device may itself comprise a semiconductor layer deposited on a support substrate.

[0197] This series of layers may also include additional layers, in particular layers interposed between a cover and an adhesive, for example an additional layer improving the adhesion between the internal surface of a cover and a layer of adhesive composition, a surface treatment of the cover, etc.

[0198] In the module thus obtained, the electronic or optoelectronic device is preferentially coated by the two adhesives, which overlap at their periphery, in order to form a watertight seal. The coating of the electronic or optoelectronic device by the adhesives, and its encapsulation between the two covers, allows it to be isolated from its environment.

[0199] The module thus obtained has satisfactory properties, making it possible to limit, or even prevent, both orthogonal permeation and lateral permeation, while retaining the flexibility properties of the electronic or optoelectronic device.

[0200] The module may have a total thickness of 50 to 500 pm, preferably 50 to 300 pm, preferably 50 to 150 pm.

[0201] The electronic or optoelectronic devices may be chosen from rigid, flexible devices or their combinations; preferably the devices are flexible devices; preferably the devices are chosen from organic light-emitting diodes, organic or perovskite photovoltaic cells, organic or perovskite transistors or sensors, or a combination of these devices.

[0202] In a particular embodiment, the photovoltaic cells are perovskite-type devices. The so-called halogenated perovskite material may comprise in its crystalline structure a metal (for example lead or tin), organic and inorganic cations (for example cesium, formamidinium and / or ammonium), halide anions (for example boron or iodine). Perovskite-type devices are particularly suitable for photovoltaic applications. However, perovskite-type devices may have stability problems over time, due to their sensitivity to the atmosphere, in particular to water vapor.

[0203] The hoods can be the same or different.

[0204] Hoods can be single-layer or multi-layer.

[0205] The hoods can be flexible or rigid, preferably flexible.

[0206] The module may have an orientation, for example in that it comprises a lower or rear cover (commonly referred to as a "backsheet" in English) and an upper or front cover (commonly referred to as a "frontsheet" in English). The upper or front cover is preferably transparent and the lower or rear cover is preferably opaque.

[0207] Depending on the electronic or optoelectronic device used and the desired module characteristics and properties, the covers can have specific properties.

[0208] A hood can be a polymer hood.

[0209] A hood can be an inorganic hood.

[0210] A polymeric cover may comprise at least one fluorinated polymeric layer obtained from at least one fluorinated polymer, for example poly(vinyl fluoride) (PVF), poly(vinylidene fluoride) (PVDF) and their mixture. A polymeric cover may comprise at least one polymeric layer obtained from polyethylene terephthalate (PET) (or PET layer) and a fluorinated polymeric layer.

[0211] The fluorinated polymer layer, the PET layer, and their combinations, and the single-layer or multi-layer covers obtained from them, are particularly suitable for use as a lower or rear cover.

[0212] A hood may include at least one layer of glass.

[0213] A cover may comprise at least one polymeric layer obtained from polymethyl methacrylate (PMMA) (or PMMA layer).

[0214] The glass layer or PMMA layer is particularly suitable for use as a top or front cover.

[0215] A flexible cover, particularly suitable for encapsulating flexible electronic or optoelectronic devices, in particular organic or perovskite cells, is commercially available under the name 3M Ultra-Barrier Solar Film from 3M®. This cover is a laminated multilayer cover comprising a PET film, an inorganic barrier layer of silica, alumina or silicon nitride type of 20 to 300 nm, a so-called PSA film (pressure sensitive adhesive) and a fluoropolymer film or layer called "weathering layer" placed in an outdoor situation in order to protect the entire environment.

[0216] Process for obtaining the electronic or optoelectronic module

[0217] In a fifth aspect, the present invention relates to a method for obtaining the module as described above, the method comprising the following steps: providing an electronic or optoelectronic device; providing an adhesive photopolymerizable composition as described above; providing a first cover; providing a second cover; applying layers of adhesive photopolymerizable composition to the surface of the device and / or to respective inner surfaces of the first and second covers; laminating the device and the layers of adhesive photopolymerizable composition between the respective inner surfaces of the first and second covers; and photopolymerizing the layers of adhesive photopolymerizable composition. The method may also comprise a step of irradiating the first cover and / or the second cover with ultraviolet-ozone radiation before the application step and / or the lamination step.

[0218] In a particular embodiment, the rigid modules are obtained by a vacuum lamination technique (referred to as “sheet to sheet” in English).

[0219] In a particular embodiment, the flexible modules are obtained by a continuous “roll-to-roll” technique, as described for example in the article by S. Razza et al., entitled “Research Update: Large-area deposition, coating, printing, and processing techniques for the upscaling of perovskite solar cell technology”, APL Materials (2016) 4(9). This technique is particularly suitable for flexible electronic or optoelectronic devices; preferably devices chosen from organic light-emitting diodes, organic or perovskite photovoltaic cells, organic or perovskite transistors and sensors, or a combination of these devices; preferably perovskite-type devices.

[0220] Applications and Uses

[0221] In a sixth aspect, the present invention relates to the use of the adhesive photopolymerizable composition as described above, and of the adhesive as described above obtained therefrom, for the encapsulation of electronic or optoelectronic devices, in particular for the encapsulation of flexible electronic or optoelectronic devices, for example for the encapsulation of organic photovoltaic devices, in particular perovskite type devices.

[0222] EXAMPLES

[0223] The following examples illustrate the invention without limiting it.

[0224] List of materials and equipment

[0225] Block copolymer: MBM triblock copolymer [polymethylmethacrylate-poly(styrene-co-butylacrylate)-polymethylmethacrylate block copolymer] (abbreviation: MBM)

[0226] (Meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature of at least 85°C: methyl methacrylate (abbreviation: MAM)

[0227] Alkoxysilane (meth)acrylate monomers: 3-(trimethoxysilane)propyl methacrylate (Silquest® A174 product from Momentive®) (abbreviation: A174) Photoinitiators: phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (Omnirad® 819 product from IGM Resins) (abbreviation: 1819), also available from Sigma-Aldrich

[0228] Methacrylic acid (abbreviation: AMA)

[0229] Zeolite: zeolite 3A, grade Siliporite® NK30APSC, marketed by Arkema

[0230] Clay: C10A marketed by Southern Clay Product; Modified clay C14-C18 (Montmorillonite MMT modified with dimethyldialkyl(C14-C18) amine at a rate of 35-45% by mass. They are from the Nanoclay range supplied by Sigma Aldrich); Octa-silane clay (Montmorillonite MMT modified with octadecylamine at a rate of 15-35% by mass and aminopropyltriethoxysilane at a rate of 0.5-5% by mass. They are from the Nanoclay range supplied by Sigma Aldrich

[0231] Light source: UV LED Delolux® 03S system

[0232] Modules to test

[0233] The modules to be tested are commonly referred to as test pieces.

[0234] PK layer: perovskite layer of formula Cso.osFAo.gsPbOo.ssBro, 12)3 with a surface area of ​​4x4 cm (16 cm 2 )

[0235] Glass layer: layer with a surface area of ​​5x5 cm (25 cm 2 )

[0236] ITO layer: tin-doped indium oxide layer

[0237] The ITO glass layers form the supporting substrate as such.

[0238] The PK layers are deposited using spin coating technology. The top ITO layer is deposited using physical vapor deposition.

[0239] The perovskite layers are deposited on the support substrate, with a 5 mm overhang between the edge of the substrate and the perovskite layer.

[0240] The modules are individually encapsulated between two glass covers with a thickness of 1.2 mm using the photopolymerizable compositions to be tested.

[0241] Test methods

[0242] Thermal properties and barriers to

[0243] The thermal and gas barrier properties of the tested modules were analyzed with a differential scanning calorimetry (DSC). The measurements are carried out over three cooling-heating cycles ranging from -80 to 200°C at a rate of 10°C per minute. The glass transition temperature is measured over the third heating cycle with the mid-height tangent method calculated between 40° and 140°C. The gas barrier properties were determined by an optical test measuring the degradation kinetics of the Perovskite layer of the specimen. The degradation rate (cm 2 / h) is determined with respect to the degradation of a perovskite layer. The degradation of the tested modules was assessed using the following method: the specimen as described above is placed in a climatic chamber at a temperature of 85°C and a relative humidity of 85% in accordance with the climatic conditions for testing photovoltaic modules reported in the standard method IEC 61615, in order to determine an algorithmic parameter of degradation rate (cm 2 / h). See the article by E. Booker et al. entitled “Perovskite Test: A high throughput method to screen ambient encapsulation conditions”, Energy Technology (2020) 8(12). Photographic images of the specimens are taken regularly, for example approximately every 48 h, in order to evaluate the aging of the perovskite layers. The residual surface area of ​​the perovskite layers (thickness) is determined, in order to calculate the degradation rate of these layers (cm 2 / h) from a linear regression of points between 12 cm 2 and 2 cm 2 Areas with a thickness of 180 nm or less are considered degraded areas (black areas by algorithmic analysis) and areas with a thickness greater than 180 nm are considered intact areas (grey areas by algorithmic analysis).

[0244] Photopolymerizable adhesive compositions

[0245] The following photopolymerizable adhesive compositions were prepared (see Table 1, proportions expressed as a mass percentage relative to the total weight of the photopolymerizable adhesive composition):

[0246] [Table 1]

[0247]

[0248] Results

[0249] Vapor barrier

[0250] The degradation rate of multilayer modules obtained with compositions C1 to C7 according to the invention and the comparative composition CRef is tested. The tested modules are photographed at regular intervals. The shots are taken at Oh, 159h, 280h, 351h, 447h, 521h, 624h, 737h, 852h, 948h and 1091h.

[0251] From these snapshots several parameters are extracted which are:

[0252] • Area of ​​the “active” surface which is the area of ​​the Perovskite (PK) layer with a thickness greater than an empirical threshold (180nm) knowing that the initial thickness of PK is 400 nm for all tests and that the initial area is of the order of 14 cm 2for all tests. o Monitoring this area (figures 1, 7 and 13) allows the VA parameter to be determined (figures 3 and 9) by the linear regression established between 12 and 3 cm2. It can be seen that the VA parameter is improved in the presence of zeolite and / or modified clay compared to the reference composition. The combination of zeolite and modified clay significantly improves the VA. o This same area monitoring allows the DA12 parameter to be defined (figures 5 and 11) which is the time after which the “active” surface reaches 12cm 2 . It is observed that DA12 is higher for the compositions according to the invention (with zeolite and / or clay) compared to the reference composition. The combination of zeolite and clay makes it possible to further increase the DA12.

[0253] Monitoring of the average thickness of the "active" surface (figures 2, 8 and 14): o the VE parameter (figures 4 and 10) obtained by the linear regression established between 340 and 230 nm. It is noted that VE is better for the compositions according to the invention (with zeolite and / or clay) compared to the reference composition. These results also show that the combination of zeolite and modified clay makes it possible to significantly improve the VA. o The DE380 parameter (figures 6 and 12), corresponding to the time after which the average thickness, starting from 400 nm, reaches 380 nm, for which it is noted that the DE380 is higher for the compositions according to the invention (with zeolite) compared to the reference composition. The combination of zeolite and clay makes it possible to further increase the DE380.

[0254] The evolution of the area of ​​the "active" surface, which is the Perovskite layer area (PK), is also given in Figure 13 for compositions C3, C5, C6 and C7. The evolution of the average thickness of the active surface is also given in Figure 14 for compositions C3, C5, C6 and C7.

[0255] It has also been observed that the addition of filler in the photopolymerizable compositions of the invention does not affect the UV transmission.

Claims

Claims 1. Photopolymerizable adhesive composition comprising, by weight per total weight of the photopolymerizable adhesive composition: at least one block copolymer, preferably a (meth)acrylic block copolymer; at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C; at least one alkoxysilane (meth)acrylate monomer; from 1 to 15% by weight of a filler chosen from a zeolite or an organically modified clay, or a mixture of zeolite and organically modified clay; and at least one photoinitiator.

2. Photopolymerizable adhesive composition according to claim 1, comprising, by weight per total weight of the photopolymerizable adhesive composition: from 10 to 60%, preferably from 10 to 50%, preferably from 20 to 40%, preferably from 20 to 35%, more preferably from 25 to 35%, of at least one block copolymer, preferably a (meth)acrylic block copolymer; from 30 to 80%, preferably from 40 to 75%, preferably from 45 to 75%, preferably from 45 to 60%, more preferably from 45 to 55%, of at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature (Tg) of at least 85°C; from 1 to 20%, preferably from 2 to 15%, preferably from 3 to 10%, preferably from 4 to 6%, of at least one alkoxysilane (meth)acrylate monomer;from 1 to 15%, preferably 1 to 12%, preferably 1 to 10%, preferentially from 1.5 to 10%, by weight of a filler chosen from a zeolite or an organically modified clay, or a mixture of zeolite and organically modified clay; and from 0.1 to 5%, preferably from 0.5 to 4%, preferably from 1 to 3.5%, preferably from 1 to 3% of at least one photoinitiator.; 3. Photopolymerizable adhesive composition according to claim 1 or 2, in which the filler is: - a type A zeolite, preferably 3A or 4A; - an organically modified clay chosen from: - an organically modified clay with quaternary ammonium ions of the type N+RiFbRsF, sulfonium ions of the type S + RIR2RS, phosphonium P ions +RIR2RSR4, R1 to R4 being the same or different and representing hydrogen, a substituted or unsubstituted C1-C25 alkyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted benzyl group, a substituted or unsubstituted carboxyalkyl group, a substituted or unsubstituted acyl group, a substituted or unsubstituted silane group, or mixtures of such clays, preferably a clay organically modified with quaternary ammonium ions of the N type + RIR2R3R4; - a mixture of said zeolite and said organically modified clay.

4. Adhesive photopolymerizable composition according to any one of the preceding claims, in which the block copolymer is chosen from the group consisting of block copolymers comprising at least one block M and at least one block B; said block M designating a polymer block comprising at least 50% by weight of methyl methacrylate; and block B designating an elastomeric polymer block incompatible with block M, and whose glass transition temperature (Tg) is less than 20°C.

5. Photopolymerizable adhesive composition according to any one of the preceding claims, in which the alkoxysilane (meth)acrylate monomer is selected from the group consisting of trialkoxysilane (meth)acrylate monomers.

6. Photopolymerizable adhesive composition according to one of the preceding claims, further comprising at least one (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature lower than 0°C, a methacrylic acid monomer, at least one urethane (meth)acrylate oligomer, at least one monofunctional reactive diluent and mixtures thereof.

7. Adhesive photopolymerizable composition according to claim 7, wherein the (meth)acrylate monomer whose homopolymer obtained after polymerization has a glass transition temperature below 0°C, if present, is selected from the group consisting of butyl acrylate, ethyl acrylate, propyl acrylate, hexyl acrylate, octyl acrylate, dodecyl acrylate, isopropyl acrylate, isobutyl acrylate, isodecyl acrylate, 2-ethylhexyl acrylate, 2-propylheptyl acrylate, isodecyl methacrylate, dodecyl methacrylate, 2-hydroxyethyl acrylate and mixtures thereof.

8. Photopolymerizable adhesive composition according to one of the preceding claims, in that it is a single-component composition.

9. Photopolymerizable adhesive composition according to any one of the preceding claims, in that it has a glass transition temperature after polymerization of at least 85°C, preferably at least 90°C, more preferably at least 100°C.

10. Adhesive product comprising the photopolymerizable adhesive composition according to one of the preceding claims and an opaque container containing it.

11. Adhesive obtained by the method comprising the following steps: application of a photopolymerizable adhesive composition according to one of claims 1 to 9 on at least one cover and / or an electronic or optoelectronic device; photopolymerization of the applied photopolymerizable adhesive composition to obtain a polymerized adhesive; and optionally shaping of the polymerized adhesive.

12. Electronic or optoelectronic module comprising the assembly of a series of layers comprising, in this order: a first cover; a first adhesive according to claim 10 or obtained from the photopolymerizable adhesive composition according to one of claims 1 to 9; a flexible electronic or optoelectronic device; a second adhesive according to claim 11 or obtained from the photopolymerizable adhesive composition according to one of claims 1 to 9; and a second cover.

13. Electronic or optoelectronic module, according to claim 12, according to which the flexible electronic or optoelectronic device is chosen from organic light-emitting diodes, organic photovoltaic cells, organic transistors, or organic sensors, or a combination of these devices.

14. Electronic or optoelectronic module, according to one of claims 12 or 13, according to which the flexible electronic or optoelectronic device is a perovskite type device.

15. A method for obtaining the module according to one of claims 12 to 14, the method comprising the following steps: providing an electronic or optoelectronic device; providing an adhesive photopolymerizable composition according to one of claims 1 to 9; providing a first cover; providing a second cover; applying layers of adhesive photopolymerizable composition to the surface of the device and / or to respective internal surfaces of the first and second covers; laminating the device and the layers of adhesive photopolymerizable composition between the respective internal surfaces of the first and second covers; and photopolymerizing the layers of adhesive photopolymerizable composition.

16. Use of the photopolymerizable adhesive composition according to one of claims 1 to 9, or of the adhesive according to claim 10 or 11, for the encapsulation of flexible electronic or optoelectronic devices.

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