Method for coating a carrier with a partially holographic photopolymer film

Abstract

The invention relates to a method for producing a carrier coated with a photopolymer film, wherein the photopolymer film is suitable for forming a holographic optical element (HOE) in a sub-region of the total surface thereof. The method product can be used in a composite glass for building glazing or in vehicle windows.

Description

[0001]METHOD FOR COATING A SUPPORT WITH A PHOTOPOLYMER FILM PARTIALLY HOLOGRAPHIC TECHNICAL FIELD The present invention relates to a method for producing a support coated with a photopolymer film, wherein the photopolymer film is suitable in a partial area of ​​its total surface to form a holographic optical element (HOE). The support coated in this way can be used, for example, in laminated glass for building glazing or in vehicle windows. BACKGROUND The production of optical components that form a holographic optical element (HOE), synonymous with a hologram, is known. Holographic optical elements typically denote those optical components in which the holographic properties are used to achieve a specific beam path of the light, such as focusing or collecting, scattering and / or reflection, etc.This allows for the implementation of specific optical functionalities. The holographic properties, in turn, exploit the wave nature of light, particularly coherence and interference effects. Both the intensity and phase of the light are taken into account. Photopolymerizable compositions that form a hologram upon exposure to UV / VIS radiation are known, for example, from WO 2022 / 171814 A1. Such photopolymer compositions, suitable for forming a holographic optical element, are similar in composition to those of light-curing adhesives. Holographic functionalization is achieved through specific additives that are added to a precisely matched mixture of monomers. These specific additives, especially borates and cationic dyes, result in significantly higher costs for HOE-capable photopolymers compared to non-HOE-capable photopolymers.German patent application DE 102015109703 B4 discloses the coating of a polymer substrate with an HOE-capable polymer layer, which is used in a process for manufacturing spectacle lenses. However, when applying holographic functionalization to larger areas, such as those used in building glazing or vehicle windshields, it becomes apparent that not the entire surface needs to be HOE-capable, but rather that holographic functionalization is only required in a sub-area of ​​the total surface. A simple solution to achieve this would be to equip the different areas of a large surface only section by section with a commercially available HOE. However, this is not a practical approach for the following reason: Such prefabricated HOEs are typically offered as films (e.g., Bayfol® HX from Covestro Deutschland AG) and must be integrated into a glass sandwich in this form.Although this is fundamentally possible, every integration process (e.g., cementing, laminated glass process, OCA laminates) always leaves visible, disruptive butt joints that, in most cases, cannot be concealed by black printing on the panes at the corresponding points. Therefore, the entire surface to be functionalized holographically would have to be covered with an HOE-capable film, because, in the vast majority of cases, the butt joints can only be concealed at the edges of the surface. However, in most applications, holographic functionalization is only required in a portion of the surface, for example, no more than 30%. In this case, two-thirds of the HOE-capable film would go unused. For high-volume production runs, this is unacceptable due to the high cost of HOEs.In light of this problem, there is a need for a cost-effective method for the production of an HOE-capable polymer film or a correspondingly coated substrate, which makes it possible to avoid disruptive butt joints, for example when used in laminated glass.SUMMARY The present invention addresses this need by providing a method for producing a substrate coated with a photopolymer film, wherein the photopolymer film is suitable in a partial region of its total surface to form a holographic optical element (HOE), comprising the following steps: (a) coating a partial region of the substrate with a photopolymerizable composition (i) suitable to form an HOE-capable photopolymer, (b) coating a partial region of the substrate immediately adjacent to the partial region coated in step (a) with a photopolymerizable composition (ii) not suitable to form an HOE-capable photopolymer, (c) curing the compositions (i) and (ii) applied to the substrate to form a continuous photopolymer film on the substrate; wherein the compositions (i) and (ii) are miscible.In a further aspect, the present invention provides a substrate with a photopolymer film coating, wherein the photopolymer film is suitable in a partial region of its total surface to form a holographic-optical element. Preferably, this substrate is obtained by the method according to the invention. In a further aspect, the present invention provides a laminated glass containing the substrate coated according to the invention. In a further aspect, the present invention relates to the use of the laminated glass according to the invention for building glazing or as a (windshield) window for a motor vehicle. The invention is described in detail below in all its aspects and preferred embodiments.DETAILED DESCRIPTION As already described in the "Summary", the present invention provides a method for producing a substrate coated with a photopolymer film, wherein the photopolymer film is suitable in a partial region of its total surface area to form a holographic optical element (HOE). The method comprises steps (a) to (c), wherein the photopolymerizable compositions (i) and (ii) used in the method are miscible. The term "holographic optical element (HOE)" is used synonymously with the term "hologram" within the scope of the present invention. The term "HOE-capable photopolymer", as used within the scope of the present invention, refers to a polymer that is suitable for forming a holographic optical element by exposure.In the context of the present invention, the term "photopolymerizable" means that compositions (i) and (ii) can be cured by exposure in step (c) of the process according to the invention. Compositions (i) and (ii) are therefore "light-curing." This is typically achieved by UV / VIS / NIR irradiation, whereby, in the context of the present invention, wavelengths in the range of 200 nm to 1100 nm are typically meant. The light curing is typically carried out by incoherent exposure. Step (c) of the process according to the invention is described below. The light curing can be carried out to form the holographic-optical element. Preferably, however, the process according to the invention comprises a separate step (d) for forming the holographic-optical element by spatially resolved exposure.Preferably, this spatially resolved exposure for the formation of the holographic-optical element is performed prior to the curing of the polymer film according to step (c) and is typically carried out by UV / VIS / NIR irradiation with wavelengths in the range of 200 nm to 1100 nm. A prerequisite for the formation or "writing" of the holographic-optical element is that a dye is used in the photopolymer composition which has sufficient absorption at the wavelength of the writing laser. Only in this way can the holographic-optical element be written, which is known to those skilled in the art. Step (d) of the process according to the invention is described below. It is essential for the process according to the invention that the compositions (i) and (ii) are miscible, whereby the miscibility of the compositions should already be given at room temperature (20 to 30°C).Accordingly, compositions (i) and (ii) are liquid at room temperature (and standard pressure, i.e., 101,325 Pa = 1.01325 bar). The miscibility of the two compositions (i) and (ii) ensures that they blend homogeneously and invisibly into one another in the area where they are applied directly adjacent to the substrate, thus forming a continuous layer on the substrate. Ideally, both compositions have the same layer thickness when applied to the substrate. Preferably, compositions (i) and (ii) are also similar in other properties, such as viscosity, mechanical properties, color, transmission properties, and refractive index. Preferably, compositions (i) and (ii) are selected such that they retain a substantially similar refractive index even after curing.This prevents the formation of a seam in the resulting film that would act like a cylindrical lens and thus be disruptive in the final product. In the context of the present invention, "essentially the same refractive index" means that the refractive index is the same at least to the first decimal place. The refractive index is determined using a method familiar to those skilled in the art, for example, by means of a prism coupler, Abbe refractometer, or ATR prism refractometer. The substrate used in the method according to the invention can be a glass substrate, for example, a glass sheet. Typically, however, the substrate is a polymer film, the polymer film preferably comprising or consisting of at least one thermoplastic polymer.The thermoplastic polymer is preferably selected from the following group: acrylonitrile butadiene styrene (ABS), polyamide (PA), polymethyl methacrylate (PMMA), polycarbonate (PC), polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS), polyetheretherketone (PEEK), polyvinyl chloride (PVC), and cellulose triacetate (TAC), with polycarbonate (PC), polyethylene terephthalate (PET), and cellulose triacetate (TAC) being particularly preferred. The support is typically transparent to visible light. Therefore, transmission of visible light can occur, at least partially, through the substrate. The transparent substrate can absorb certain spectral ranges of light more strongly than others. In this way, selective transmission can be implemented. The thickness of the support layer is typically in the range of 30 to 250 µm, preferably in the range of 60 to 150 µm, for example, around 125 µm.Typically, compositions (i) and (ii) are applied directly to the substrate. However, it is also possible that one or more additional layers are arranged on the substrate, onto which compositions (i) and (ii) are applied. This could, for example, be a primer layer to improve the adhesion of the photopolymer film. Alternatively or additionally, it is also possible that a fixative layer for fixing compositions (i) and (ii) is located between the photopolymer film and the substrate. The photopolymerizable composition (i) used in step (a) of the process according to the invention typically comprises the following components: - a monomer or a monomer mixture for forming an HOE-capable photopolymer, - at least one photoinitiator, - further additives for forming the holographic optical element, wherein the further additives comprise at least one dye and at least one co-photoinitiator. Optionally, the composition (i) used in step (a) of the process according to the invention further comprises one or more of the following components: - at least one solvent, - at least one additive. The components of the composition are mixed together shortly before coating and then cure on the substrate.Monomers or monomer mixtures for the formation of the HOE-capable photopolymer. Suitable monomers or monomer mixtures for the formation of the HOE-capable photopolymer, which can be used in composition (i), are known, for example, from WO 2022 / 171814 A1 and are expressly described again below. Accordingly, monomers M1, comprising at least one ethylene unsaturated group, are typically used. Preferably, monomers M2, comprising at least two ethylene unsaturated groups, are used, wherein M2 preferably differs from M1 only by the second ethylene unsaturated group. The use of a monomer mixture containing monomers M1 and monomers M2 is also possible. The monomer M1, comprising at least one ethylene unsaturated group, can have the following general structural units: , where n, m = 0-12, preferably 1-12; o = 0,1; and Ar is a mono- or polynuclear substituted or unsubstituted aromatic or heterocyclic aromatic residue, wherein residue R1 is H, methyl, or ethyl, and wherein residues R2 and R3 are independently selected from the group consisting of alkyl, alkenyl, alkynyl, alkoxy, acyl, and acyloxy residues, which may be straight- or branched-chain, unsubstituted or substituted, substituted or unsubstituted aryloxy residues, substituted or unsubstituted aromatic or heterocyclic residues, unsubstituted or substituted alicyclic hydrocarbon residues, aliphatic, aromatic, and aliphatic aromatic amino, carboxylic acid, amido, and imido residues, hydroxy, amino, cyano, nitro, halogen atoms, or hydrogen atoms, and combinations of the aforementioned residues, wherein the substituted residues may be substituted with C1-C 12 Alkyl-, C1-C 12Alkoxy, hydroxy, carboxy, carbonyl, amino, amido, imido residues, halogen atoms, aromatic residues, or combinations thereof. Examples of suitable monomers M1 are substituted or unsubstituted styrene monomers, acrylic acid, α-alkylacrylic acid, acrylic esters, α-alkylacrylic esters, the alcohol component of which may be a substituted or unsubstituted aliphatic or aromatic residue with 2-50 carbon atoms, acrylamides, α-alkylacrylamides, where alkyl has the meaning given above, vinyl esters, vinyl alcohols, vinyl ethers, and other substituted vinylic monomers, substituted with substituted or unsubstituted aliphatic or aromatic residues with 2-50 carbon atoms. Preferred examples of suitable monomers M1 are (Meth)acrylic acid butyl ester, (Meth)acrylic acid phenyl ester, (Meth)acrylic acid benzyl ester, (Meth)acrylic acid isobornyl ester, (Meth)acrylic acid cyclohexyl ester, (Meth)acrylic acid 2-phenoxyethyl ester, (Meth)acrylic acid- 1H,1H,2H,2H-perfluoroctylester, 2,2,2-Trifluorethyl(meth)acrylat, Heptafluorpropyl(meth)acrylat, 1,1,1,3,3,3-Hexyfluorisopropyl(meth)acrylat, 2,2,3,3- Tetrafluorpropyl(meth)acrylat), 2,2,3,3,4,4,4-Heptafluorbutyl(meth)acrylat, 2,2,3,3,4,4,5,5- Octafluorpentyl(meth)acrylat, Acrylsäure-N,N-diethylaminoethylester, Acrylsäureethoxyethyoxyethylester, Acrylsäure-2-(p-chlorphenoxy)ethylester, p- Chlorphenylacrylat, 2-Phenylethyl(meth)acrylat, Pentachlorphenylacrylat, Phenylacrylat, p- Chlorstyrol, n-Vinylcarbazol, 1 -Vinyl-2-pyrolidon, 2-Chlorstyrol, 2-Bromstyrol, Methoxystyrol, Phenolethoxylatacrylat, 2-(p-Chlorphenoxy)-ethylacrylat, 2-(1-Naphthyloxy)ethylacrylat, Hydrochinonmonomethacrylat und 2-[ß-(N-Carbazolyl)propionyloxy]ethylacrylat. Besonders bevorzugte Monomere M1 sind N-Vinylcarbazol, Ethoxyethoxyethylacrylat, 2- Naphthylacrylat, 2-Phenoxyethylacrylat, 2-Phenoxyethylmethacrylat, Phenolethoxylatacrylat, 2-(p-Chlorphenoxy)ethylacrylat, p-Chlorphenylacrylat, Phenylacrylat, 2-Phenylethylacrylat,2-(1-Naphthyloxy)ethyl acrylate, t-butyl acrylate, isobornyl acrylate, cyclohexyl acrylate, N,N-diethylaminoethyl acrylate, acrylamide, ethoxyethoxyethyl acrylate, 1H,1H,2H,2H-perfluorooctyl methacrylate, and pentafluoroethyl acrylate. Preferably, a monomer M2 comprising at least two ethylene-unsaturated groups is used, i.e., the monomer is preferably difunctional. Difunctional ethylene-unsaturated monomers M2 have two C-C double bonds in the molecule, i.e., they contain, for example, two of the structural units listed above. A difunctional ethylene-unsaturated monomer may, for example, contain two acrylate or methacrylate groups. The monomer may consist exclusively of one or more difunctional or higher-functional monomers, i.e., the composition may be free of monofunctional ethylene-unsaturated monomers. Preferred monomers M2 with at least two ethylene unsaturated groups are ethoxylated bisphenol A diacrylates,In particular, compounds of the following formula, where R1, Q and Ar have the meanings given above. A particularly preferred monomer M2 is the compound of the following structural formula: Such monomers or monomer mixtures can be added in a customary amount, for example, in an amount of 40 to 99.79 wt.%, preferably in an amount of 50 to 97.9 wt.%, based on the total weight of composition (i). Photoinitiator: Typically, composition (i) contains at least one photoinitiator. Suitable photoinitiators that can be used in composition (i) are known, for example, from WO 2022 / 171814 A1 and are expressly described again below. Radical-forming polymerization initiators are known; see, for example, Timpe, HJ and S. Neuenfeld, "Dyes in photoinitiator Systems", Kontakte (1990), pages 28-35 and Jakubiak, J. and JF Rabek, "Photoinitiators for visible light polymerization", Polimery (Warsaw) (1999), 44, pages 447-461. Suitable radical-forming polymerization initiators include,The substituted or unsubstituted polynuclear quinones, which can be activated by UV radiation and are generally inactive at temperatures up to 185°C, are among them; These are compounds with two intracyclic carbon atoms in a conjugated carbocyclic ring system, e.g., 9,10-anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthrenequinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dichloronaphthoquinone, 1,4-dimethylanthraquinone, 2,3-dimethylanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, sodium salt of anthraquinone-α-sulfonic acid. 3-Chloro-2-methylanthraquinone, retenquinone, 7,8,9,10-tetrahydronaphthacenequinone, and 1,2,3,4-tetrahydrobenz[a]anthracene-7,12-dione. Other suitable photoinitiators include:Although some are thermally active at temperatures as low as 85°C, they are described in US Patent 2760663 A and include vicinal ketaldonyl alcohols such as benzoin, pivaloin, acyloin ethers (e.g., benzoin methyl and ethyl ethers), and α-hydrocarbon-substituted aromatic acyloins, including α-methylbenzoin, α-allylbenzoin, and α-phenylbenzoin. Photoreducible dyes and reducing agents such as those disclosed in US Patents 2850445 A, 2875047 A, 3097096 A, 3097097 A, 3145104 A, and 3579339 A, as well as dyes from the class of phenazines, oxazines, and quinones, can be used as photoinitiators. Michler's ketone, benzophenone, 2,4,5-triphenylimidazolyl dimers with hydrogen donors and mixtures thereof, as described in US patents 3427 161 A, 3479185 A, 3549367 A, 4311783 A,4622286 A and 3784557 A. A discussion of dye-sensitized photopolymerization can be found in "Dye Sensitized Photopolymerization" by DF: Eaton in Adv. in Photochemistry, Vol. 13, DH Volman, G.S. Flammond, and K. Gollnick, eds., Wiley-Interscience, New York, 1986, pp. 427–487. Similarly, the cyclohexadienone compounds of US Patent No. 4341860 are also suitable as initiators. Suitable photoinitiators include CDM-FIABI, i.e., 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazole dimer; o-CI-HABI, i.e., 2,2'-bis(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,1'-biimidazole; and TCTM-FIABI, i.e., 2,5-bis(o-chlorophenyl)-4-(3,4-dimethoxyphenyl)-1H-imidazole dimer, each typically used with a hydrogen donor, e.g., 2-mercaptobenzoxazole. Particularly preferred UV photoinitiators include, for example, IRGACURE® OXE-01 (1 ,2-Octanedione-1-[4-(phenylthio)-phenyl]-2-(O-benzoyl oxime) and IRGACURE® OXE-02 (1-[9-Ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone-O-acetyl oxime from BASF AG, as well as OMNIRAD-MBF (methylbenzoyl formate), OMNIRAD-TPO (2,4,6-trimethylbenzoyl-diphenyl phosphine oxide), OMNIRAD-TPO-L (ethyl-(2,4,6-trimethylbenzoyl)-phenyl phosphinate), OMNIRAD-1173 (2-hydroxy-2-methyl-1-phenylpropanone), OMNIRAD 1000 (mixture of 2-hydroxy-2-methyl-1-phenylpropanone (80%) and 1-hydroxycyclohexyl phenyl ketone (20%)), OMNIRAD 184 (1-Hydroxycyclohexyl phenylketone), OMNIRAD 819 (Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide), OMNIRAD 2022 (mixture of 2-hydroxy-2-methyl-1-phenylpropanone, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and ethyl(2,4,6-trimethylbenzoyl)phenylphosphinate) and OMNICAT 440 (4,4'-Dimethyl-diphenyl-iodonium hexafluorophosphate), which are available from IGM Resins and preferably in an amount of 0,They can be used in concentrations of 1 to 10% by weight. The photoinitiators mentioned above can be used alone or in combination. Preferably, the photoinitiator is liquid and / or selected from the group consisting of 1,2-octanedione-1-[4-(phenylthio)phenyl]-2-(O-benzoyl oxime), (1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone-O-acetyl oxime, methylbenzoyl formate), 2,4,6-trimethylbenzoyl diphenyl phosphine oxide, ethyl (2,4,6-trimethylbenzoyl) phenyl phosphinate), 2-hydroxy-2-methyl-1-phenylpropanone, a mixture of 2-hydroxy-2-methyl-1-phenylpropanone (80%) and 1-hydroxycyclohexyl phenyl ketone (20%), 1-hydroxycyclohexyl phenyl ketone, bis(2,4,6-trimethylbenzoyl)phenyl phosphine oxide, a mixture of 2-hydroxy- 2-methyl-1-phenylpropanone, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and ethyl(2,4,6-trimethylbenzoyl)phenylphosphinate), and 4,4'-dimethyl-diphenyl-iodonium hexafluorophosphate. Such photoinitiators can be found in typical quantities,for example, in an amount of 0.1 to 10 wt.%, preferably in an amount of 1 to 5 wt.%, based on the total weight of composition (i). Further additives for the formation of the holographic-optical element: Composition (i) typically comprises further additives required for the formation of the holographic-optical element. These further additives comprise at least one dye and at least one co-photoinitiator, which are described below. The use of these further additives leads to significantly higher costs for the HOE-capable photopolymer compared to a light-curing polymer with similar properties that is not HOE-capable. The inventive method, in which only a portion of the substrate is coated with an HOE-capable photopolymer composition, reduces these costs.since the remaining part of the support is coated with a non-HOE-capable photopolymer composition that does not contain such additives. Dyes: Suitable dyes that can be used in composition (i) are known, for example, from WO 2022 / 171814 A1 and are expressly described again below. Accordingly, the dye serves as a sensitizing agent for the co-photoinitiator. For this purpose, methylene blue and the sensitizing agents disclosed in US patents 3554753 A, 3563750 A, 3563751 A, 3647467 A, 3652275 A, 4162162 A, 4268667 A, 4454218 A, 4535052 A and 4565769 A, as well as the dyes and co-photoinitiators mentioned in application WO 2012062655 A2, to which express reference is made herein, are suitable, for example. Particularly preferred sensitizing agents include the following: DBC, i.e., 2,5-bis[(4-diethylamino-2-methylphenyl)methylene]cyclopentanone; DEAW, i.e., 2,5-Bis[(4-diethylaminophenyl)methylene]cyclopentanone; Dimethoxy-JDI, i.e., 2,3-Dihydro-5,6-dimethoxy-2-[(2,3,6,7-tetrahydro-1H,5H-benzo[i,j]quinolizin-9-yl)methylene]-1H-inden-1-one; and Safranin O, i.e., 3,7-Diamino-2,8-dimethyl-5-phenylphenazinium chloride. Preferably, the dye used in composition (i) is a fluorescent dye, which may, for example, consist of a cationic dye and an anion. The cationic dye can be represented by the formula F, + be reproduced. Accordingly, a cationic dye of the formula F+ is preferably understood to be one of the following formulas: in which X 1 for O, S, NR 6 or CR 6a R 6b stands, X 2 for N or CR 5 stands, R 5 for hydrogen, cyano, C1- to C4-alkyl, C4- to C7-cycloalkyl, possibly replaced by C1- to C4-alkoxycarbonyl or NR 7 R 8 substituted C6 to C 10-aryl, a heterocyclic residue or for C6- to C 10 -Aryl substituted with a carboxyl group, R 6 for hydrogen, C1 to C 16 -Alkyl, C4- to C7-cycloalkyl, C7- to C 16 -Aralkyl, C6- to C 10 - Aryl or a heterocyclic residue, R 6a and R 6b independently of each other for methyl, ethyl or together for a -CH2-CH2-CH2- or -CH2-CH2-CH2-CH2 bridge or for C6- to C 10 -Aryl substituted with a carboxyl group, R 1 to R 4 , R 7 and R 8 independently of each other for hydrogen, C1 to C 16 -Alkyl, C4- to C7- Cycloalkyl, C7- to C 16 -Aralkyl, C6- to C 10 -aryl or a heterocyclic residue or NR 1 R 2 , NR 7 R 4 and NR 7 R 8independently of each other, they represent a five- or six-membered saturated ring linked via N, which may additionally contain an N or O and / or be substituted by non-ionic residues, or R 1 to R 4 , R 7 and R 8 independently of each other, they form a two- or three-membered bridge with a carbon atom adjacent to the nitrogen atom of the benzene ring, which may contain an oxygen or nitrogen and / or may be substituted by nonionic groups, R 9 , R 9a , R 9b , R 10 , R 10a and R 10b stand independently for hydrogen, halogen or C1 to C4 alkyl, in which R 15 for hydrogen, halogen, C1- to C4-alkyl, C1- to C4-alkoxy or NR 18 R 19 stands, R 11 to R 14 , R 18 and R 19 independently of each other for hydrogen, C1 to C 16 -Alkyl, C4- to C7-cycloalkyl, C7- to C 16-Aralkyl, C6- to C 10 -aryl or a heterocyclic residue or NR 11 R 12 , NR 13 R 14 and NR 18 R 19 independently of each other, they represent a five- or six-membered saturated ring linked via N, which may additionally contain an N or O and / or be substituted by non-ionic residues, or R 12 ; R 17 b, R 13 ; R 17c and R 18 ; R 17a independently form a two- or three-membered bridge, which may contain an O or N and / or be substituted by non-ionic residues, R 16 R stands for hydrogen, chlorine, methyl, methoxycarbonyl or ethoxycarbonyl 16a R stands for hydrogen, chlorine or methyl. 17a , R 17b and R 17cThese can be independent of each other and represent hydrogen, chlorine, methyl, or methoxy. Nonionic residues include C1- to C4-alkyl, C1- to C4-alkoxy, halogen, cyano, nitro, C1- to C4-alkoxycarbonyl, C1- to C4-alkylthio, C1- to C4-alkanoylamino, benzoylamino, mono- or di-C1- to C4-alkylamino. Alkyl, alkoxy, cycloalkyl, aryl, and heterocyclic residues may optionally bear further residues such as alkyl, halogen, nitro, cyano, CO-NH2, alkoxy, trialkylsilyl, trialkylsiloxy, or phenyl; the alkyl and alkoxy residues may be straight-chain or branched; the alkyl residues may be partially or perhalogenated; the alkyl and alkoxy residues may be ethoxylated, propoxylated, or silylated; adjacent alkyl and / or alkoxy residues on aryl or heterocyclic residues may jointly form a three- or four-membered bridge; and the heterocyclic residues may be benzannelated and / or quaternized.Halogens are understood to be fluorine, chlorine, bromine, or iodine, preferably fluorine, chlorine, or bromine. Examples of substituted alkyl groups are trifluoromethyl, chloroethyl, cyanomethyl, cyanoethyl, and methoxyethyl. Examples of branched alkyl groups are isopropyl, tert-butyl, 2-butyl, and neopentyl. Examples of alkoxy groups are methoxy, ethoxy, and methoxyethoxy. Preferred, optionally substituted, C1 to C4 alkyl groups are methyl, ethyl, n-propyl, isopropyl, n-butyl, 2-butyl, isobutyl, tert-butyl, perfluorinated methyl, perfluorinated ethyl, 2,2-trifluoroethyl, 3,3,3-trifluoroethyl, perfluorobutyl, cyanoethyl, methoxyethyl, and chloroethyl. Preferred aralkyls include, for example, benzyl, phenethyl, or phenylpropyl. Examples of C6 to C... 10-Aryl groups are phenyl and naphthyl. Examples of substituted aryl groups are tolyl, chlorophenyl, dichlorophenyl, methoxyphenyl, nitrophenyl, cyanophenyl, dimethylaminophenyl, and diethylaminophenyl. Examples of heterotary groups, especially five- or six-membered heterocyclic groups, are indolyl, pyridyl, quinolyl, and benzthiazolyl. Examples of substituted heterocyclic groups are 1,2-dimethylindol-3-yl and 1-methyl-2-phenylindol-3-yl. Anions for the cationic dyes of formula F + Examples of suitable cationic dyes include anions of the halogens, sulfates, carbonates, or nitrates. Particularly suitable cationic dyes are malachite green, methylene blue, safranin O, and rhodamines of formula III. , in which R a , R b , R c , R d , R e , R f and R geach H or an alkyl group, and X- stands for chloride ion, trifluoromethanesulfonate, naphthalene disulfonate, para-toluenesulfonate, hexafluorophosphate, perchlorate, meta-nitrobenzenesulfonate or meta-aminobenzenesulfonate, e.g. Rhodamine B, Rhodamine 6G or Violamin R, also Sulforhodamine B or Sulforhodamine G, as listed below: 5 10. Other suitable dyes are fluorones, such as those described by Neckers et al. in J. Polym. Sci., Part A, Poly. Chem., 1995, 33, 1691-1703. Of particular interest is Examples of other suitable dyes are cyanines of formula IV. , in which R IV = Alkyl; n 1= 0, 1, 2, 3 or 4 and Y1 = CH=CH, N-CH3, C(CH3)2, O, S or Se. Cyanines are preferred, wherein Y1 in formula IV is C(CH3)2 or S. Preferably, the dye for composition (i) is selected from the group consisting of acriflavins, diaminoacridines, rhodamine B, safranin O, diethyl safranin and methylene blue. Such dyes may be added in a customary amount, for example, in an amount of 0.1 to 20 wt.%, preferably in an amount of 1 to 10 wt.%, based on the total weight of composition (i). Co-photoinitiator. Suitable co-photoinitiators that may be used in composition (i) are known, for example, from WO 2022 / 171814 A1 and are expressly described again below. Accordingly, the co-photoinitiator comprises in particular a borate of the following formula (I) , in which R 1c C1-C 20 -Alkyl, C3-C 12-Cycloalkyl, C2-C8-alkenyl, phenyl-C1-C6-alkyl or naphtyl-C1-C3-alkyl, where the C1-C 20 -Alcyl, C3-C 12 -Cycloalkyl, C2-C8-alkenyl, phenyl-C1-C6-alkyl or naphtyl-C1-C3-alkyl with one or more groups O, S(O) p or NR 5c may be interrupted or where the residues C1-C 20 -Alkyl, C3-C 12 -Cycloalkyl, C2-C8-alkenyl, phenyl-C1-C6-alkyl or naphtyl-C1-C3-alkyl unsubstituted or with C1-C 12 -Alkyl, OR6, R 7c SO) p , R 7C S(O)2O, NR 8c R 9c , SiR 10c R 11c R 12c , BR 13c R 14c or R 15c R 16c P(O) q , are substituted; R 2c , R 3c and R 4c independently mean phenyl or biphenyl, where the residues are phenyl or biphenyl unsubstituted or with unsubstituted or with OR 6c , NR 8c R 9c or halogen-substituted C1-C12 -Alkyl, OR 6c , R 7c SO) p , R 7c S(O)2O, R 8c R 9c NS(O)2, NR 8c R 9c , NR 3c R 8c CO, , SiR10cR11cR12c, BR13cR14c, halogen, R15cR16cP(O)q, are substituted; R 5c Hydrogen, C1-C 12 -Alkyl, unsubstituted or one- to five-fold with C1-C6 alkyl, C1-C 12 - Alkoxy or halogen-substituted phenyl C1-C6 alkyl or unsubstituted or one- to five-fold with C1-C6 alkyl, C1-C 12 -Alkoxy or halogen-substituted phenyl means; R6c and R7c unsubstituted or halogen-substituted C1-C12 alkyl, unsubstituted or one- to five-fold C1-C6 alkyl, C1-C 12 -Alkoxy or halogen-substituted phenyl-C1-C6-alkyl or unsubstituted or one- to five-fold with C1-C6-alkyl, C1-C 12 -Alkoxy or halogen-substituted phenyl; R 8c , R 9c , R 10c , R 11c , R 12c, R 13c , R 14c , R 15c and R 16c independently of each other C1-C 12 -Alkyl, C3- C 12 -Cycloalkyl, unsubstituted or one- to five-fold with C1-C6-A-Kyl, C1-C 12 -Alkoxy or halogen-substituted phenyl-C1-C6-alkyl or unsubstituted or one- to five-fold with C1-C6-alkyl, C1-C 12 -Alkoxy or halogen-substituted phenyl, or R 8c and R 9c together with the nitrogen atom to which they are bonded, they form a 6-membered aliphatic ring, which may also contain oxygen or sulfur as an additional heteroatom; R 17c' , R 18c , R 19c and R 20c independently of each other hydrogen, unsubstituted or with C1-C 12 -Alkoxy substituted C1-C 12 -Alkyl, phenyl or phenyl-C1-C6-alkyl, where the phenyl or phenyl-C1-C6-alkyl groups are unsubstituted or one to five times modified with C1-C6-alkyl, C1-C 12-alkoxy or halogen substituted; p represents a number from 0 to 2; r represents a number from 0 to 5; R 21c for hydrogen or C1-C 12 -Alkyl stands; R 22c , R 22a , R 23c and R 24c independently of each other hydrogen, unsubstituted or with C1-C 12 -Alkoxy, OH or halogen-substituted C1-C 12 -Alkyl or unsubstituted or with C1-C 12-alkoxy, OH, or halogen-substituted phenyl; q represents either 0 or 1; and G represents a residue that can form positive ions. Preferably, the co-photoinitiator is selected from the group consisting of tetrabutylammonium tetrahexyl borate, tetrabutylammonium triphenylhexyl borate, tetrabutylammonium tris-(3-fluorophenyl)hexyl borate, and tetrabutylammonium tris-(3-chloro-4-methylphenyl)hexyl borate, or mixtures thereof. A co-photoinitiator with the structural formula aa, developed by Ciba Specialty Chemicals Inc. under the name "CGI 7460" and now available from BASF AG under the name SEC LCA 1460, is particularly preferred and is represented as follows: The previously described co-photoinitiators can be added in a customary amount, for example, in an amount of 0.01 to 10 wt%, preferably in an amount of 0.1 to 10 wt%, based on the total weight of composition (i). Solvent: Composition (i) optionally comprises a solvent. Suitable solvents are known, for example, from WO 2022 / 171814 A1 and are expressly described again below. Suitable solvents can therefore be selected, for example, from the following group: ethanol, propanol, isopropanol, butanol, isobutanol, tert-butanol, pentanol, isopentanol, tert-pentanol, hexanoyl, heptanols, glycols, diglycyl, triglycol; Water, methanol, ethanol, propanol, butanol, ketones, acetone, methyl ethyl ketone, ether, tetrahydrofuran, 1,4-dioxane, trioxane; Triethanolamine (TEA), castor oil, Castor oil glycidyl ether, octanoic acid, tert-butyl peroxybenzoate, 2-dimethylaminoethanol,Anisole, poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol), benzyl alcohol, tetrachloroethylene, dipropylene glycol dimethyl ether, dichloromethane, acetic anhydride, propylene carbonate, n-butyl acetate, cyclohexane, cyclopentanone, ethylene glycol, polyethylene glycols, toluene, eucalyptus oil, butyl glycolate (Polysolvan-O), N-methyl-2-pyrrolidone (NMP), propylene glycol monomethyl ether acetate (PGMEA), poly(bisphenol-A-co-epichlorohydrin), trimethylolpropane ethoxytriacrylate (TMPEOTA), trimethylolpropane triacrylate (TMPTA), tripropylene glycol diacrylate (TrPGDA), N,N-dimethylacrylamide. Preferably, dimethyl sulfoxide (DMSO), N,N'-dimethylpropylene urea, N-hydroxyethylacrylamide (HEAA), benzaldehyde, polycaprolactones (PolyCLO, Capromer PT-05), polycaprolactonetriol, polyethylene glycol (PEG-200), acrylic block copolymer (Efka PX 4701). It is particularly advantageous if the UV photoinitiators, which are required anyway in the photopolymerizable composition,can also be used as good solvents for the dyes. However, the addition of room-temperature powdered UV photoinitiators to the solvent mixture can also increase the solubility of the dyes. Preferably, the solvent contains a polymer that is liquid at standard pressure. Advantageously, the polymer that is liquid at standard pressure can be selected from the group consisting of polyethylene glycols (PEGs), polycaprolactones, acrylate block copolymers (EFKA), and poly(bisphenol A-co-epichlorohydrins) (EPI). The use of solvents in composition (i) may necessitate that the curing process includes thermal curing by heating or drying. Such solvents can be added in a customary amount, for example, 0 to 20 wt.%, preferably 1 to 10 wt.%, based on the total weight of composition (i).Additives. To improve printability, surface adhesion, viscosity, film formation, flexibility, hardness, and resistance to cold, heat, and weathering, various additives known per se may be added to composition (i). Suitable additives are described, for example, in WO 2022 / 171814 A1. These additives include, for example, fillers, dyes, plasticizers, surfactants, common components used in photopolymer systems, polymeric binders, wetting agents, leveling agents, defoamers, adhesion promoters, surface additives, nanoscale particles, optical brighteners, or mixtures thereof. Such additives may be added in a customary amount, for example, 0 to 20 wt.%, preferably 0.01 to 10 wt.%, based on the total weight of composition (i). Polymer matrix. Composition (i) may be incorporated into a polymer matrix or a monomer or a monomer mixture suitable forto form a polymer matrix. The polymer matrix is ​​typically a polyurethane matrix obtained by polyaddition of a monomer mixture containing polyisocyanate and polyols. The composition (ii) used in step (b) of the process according to the invention is similar in its properties, particularly with regard to mechanical properties, color appearance, transmission properties, viscosity, and refractive index, to composition (i). This ensures that compositions (i) and (ii) do not form a disruptive interface where they meet, but rather blend homogeneously and invisibly into one another in the interface. Composition (ii) therefore typically comprises the following components: - a light-curing monomer or monomer mixture. Preferably, composition (ii) further comprises one or more of the following components: - at least one photoinitiator. Optionally, composition (ii) further comprises one or more of the following components: - at least one solvent, - at least one additive.Light-curing monomer or monomer mixture: The light-curing monomer or monomer mixture can be selected, for example, from the monomers described for composition (i). However, when selecting the monomers for composition (ii), it is only important that their properties are similar to those of composition (ii). Unlike composition (i), the selection of monomers for composition (ii) does not need to be specifically aimed at creating an HOE-capable photopolymer. Therefore, composition (ii) can, in principle, also use monomers and monomer mixtures other than those previously described for composition (i). Further preferred and optional components: The further preferred and optional components for composition (ii) can be selected as previously described for composition (i).The composition (ii) can be embedded in a polymer matrix as previously described for composition (i). No further additives for the formation of a holographic-optical element. A key aspect of the process according to the invention is the fact that composition (ii) does not contain any of the further additives required in composition (i) for the formation of the holographic-optical element (HOE). In particular, composition (ii) does not contain any cationic dyes or borates, especially not the cationic dyes and borates described above for composition (i). This makes it possible to coat the portion of the substrate where no holographic functionalization is required at a comparatively low cost, while the more expensive holographic functionalization is only carried out in the portion of the substrate where it is actually needed.Further aspects of process steps (a) to (c): As already mentioned, the components of compositions (i) and (ii) are mixed together only shortly before coating. Compositions (i) and (ii) can then be applied to the substrate in step (a) and step (b), respectively, using methods known to those skilled in the art, for example, by means of a gravure roller, doctor blade, or slot nozzle. The coating of the substrate with compositions (i) and (ii) in step (a) and step (b) of the process according to the invention can be carried out in parallel (simultaneously) or sequentially (one after the other), with parallel application being preferred. If application is carried out sequentially (which should be done in short or immediate succession), the order in which compositions (i) and (ii) are applied is irrelevant. In other words, steps (a) and (b) of the process according to the invention do not prescribe a fixed sequence.Since compositions (i) and (ii) are applied directly adjacent to one another, they mix at the interface and thus form a uniform, light-curing film, which is cured in step (c) of the process according to the invention. The curing according to step (c) is typically carried out by exposure using UV / VIS / NIR irradiation, typically at wavelengths in the range of 200 nm to 1100 nm, preferably in the range of 300 nm to 950 nm, and particularly preferably in the range of 370 nm to 800 nm. Within the scope of the present invention, this step is also referred to as "bleaching," since, particularly if step (c) is preceded by the exposure step according to step (d) for forming ("writing") the HOE, organic residues of the dye may be present that could cause discoloration of the exposed photopolymer. The "bleaching" destroys such organic residues.The bleaching process therefore comprises two aspects: firstly, the curing of the photopolymerizable compositions (i) and (ii), and secondly, the destruction of the organic residues of the dye that may occur after exposure to form the HOE according to step (d) (which is preferably preceding step (c) in the process according to the invention). If necessary, the curing according to step (c) may also include thermal curing by heating or drying. Preferably, the method according to the invention comprises a separate step (d) for forming the holographic-optical element by spatially resolved exposure. Preferably, this spatially resolved exposure for forming the holographic-optical element is performed upstream of step (c) of curing. The spatially resolved exposure for forming the holographic-optical element can be carried out using techniques known to those skilled in the art, e.g., writing techniques in which one or more laser beams are guided or rasterized across the surface of the HOE-capable polymer layer; in this case, the laser beams can have comparatively small beam diameters. Alternatively or additionally, interference techniques can be used in which several comparatively large-area laser beams are employed.Typical wavelengths for spatially resolved exposure to form the holographic-optical element are in the range of 200 nm to 1100 nm, preferably from 350 nm to 950 nm, and particularly preferably from 370 nm to 760 nm. Spatially resolved exposure can change the refractive index of the HOE-capable polymer layer by 0.005 to 0.05. The layer thickness of the photopolymer film resulting from steps (a) to (c), optionally including step (d), on the substrate is typically in the range of 0.1 µm to 100 µm, preferably in the range of 1 µm to 100 µm. Typically, the portion of the total area of ​​the photopolymer film suitable for forming a HOE is less than 50% of its total area, preferably less than 30%. Protective film: In a further embodiment of the process according to the invention, the photopolymer film resulting from steps (a) and (c) of the process according to the invention can be provided with a protective film. The top layer is typically a polymer film, wherein the polymer is selected, for example, from the following group: polyethylene (PE), polyethylene terephthalate (PET), cellulose triacetate (TAC), and other products and their properties. The present invention also provides a substrate with a photopolymer film coating, wherein the photopolymer film is suitable in a partial region of its total surface to form a holographic optical element (HOE). All aspects described above apply to the substrate according to the invention. Preferably, said substrate is obtained according to the inventive method. The substrate according to the invention can, for example, be used in laminated glass. The present invention therefore also provides laminated glass comprising the coated substrate obtained from the inventive method. The laminated glass according to the invention is typically a glass sandwich into which the inventively coated substrate is integrated. The laminated glass according to the invention can then be used for building glazing or as a windshield in a motor vehicle. LIST OF FIGURES Fig.Figure 1 shows an embodiment for coating a substrate film with two photopolymer compositions using a comma doctor blade. EMPLOYMENT EXAMPLE According to Figure 1, a substrate film 1 is coated simultaneously with the photopolymerizable compositions 2 and 3. Composition 2 is a holographic photopolymerizable composition, while composition 3 is a simplified, non-holographic photopolymerizable composition. The latter contains, in particular, no cationic dyes, no borates, and no precisely matched monomer mixture. The two compositions are miscible. Compositions 2 and 3 are applied to the substrate film 1, which is advanced by a breast roller 6, using a comma doctor blade 5. Within the comma doctor blade 5, compositions 2 and 3 are stored in separate reservoirs separated by a partition.The coating of the carrier film 1 with the compositions 2 and 3 results in a two-part photopolymer film-coated carrier film 4, wherein the part of the photopolymer film (4a) resulting from composition 2 is suitable to form a holographic-optical element and the part of the photopolymer film (4b) resulting from composition 3 is not suitable to form a holographic-optical element.

Claims

Claims 1. A method for producing a substrate coated with a photopolymer film, wherein the photopolymer film is suitable in a partial region of its total surface to form a holographic optical element (HOE), comprising the following steps: (a) coating a partial region of the substrate with a photopolymerizable composition (i) suitable to form an HOE-capable photopolymer, (b) coating a partial region of the substrate immediately adjacent to the partial region coated in step (a) with a photopolymerizable composition (ii) not suitable to form an HOE-capable photopolymer, (c) curing the compositions (i) and (ii) applied to the substrate to form a continuous photopolymer film on the substrate; wherein the compositions (i) and (ii) are miscible. 2.The method of claim 1, wherein the photopolymerizable composition (i) used in step (a) comprises: - a monomer or a monomer mixture for the formation of an HOE-capable photopolymer, - at least one photoinitiator, - further additives for the formation of the holographic optical element, wherein the further additives comprise at least one dye and at least one co-photoinitiator; 3. The method of claim 2, wherein the dye is selected from the group of cationic dyes, and the co-photoinitiator is selected from the group of borates.

4. The method of claim 2 or 3, wherein the photopolymerizable composition (i) used in step (a) further comprises: - at least one solvent and / or - at least one additive.

5. A method according to any one of claims 1 to 4, wherein the photopolymerizable composition (ii) used in step (b) comprises: - a light-curing monomer or monomer mixture, and preferably: - at least one photoinitiator, and optionally: - at least one solvent and / or - at least one additive.

6. A method according to any one of claims 1 to 5, wherein the photopolymerizable composition (ii) does not comprise cationic dyes or borates.

7. A method according to any one of claims 1 to 6, wherein the photopolymerizable composition (ii) is selected such that, after curing, it has a substantially the same refractive index as composition (i). 8.A method according to any one of claims 1 to 7, wherein the carrier is a polymer film, the polymer film preferably comprising at least one thermoplastic polymer selected from the group consisting of acrylonitrile butadiene styrene (ABS), polyamide (PA), polymethyl methacrylate (PMMA), polycarbonate (PC), polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS), polyetheretherketone (PEEK), polyvinyl chloride (PVC), and cellulose triacetate (TAC).

9. A method according to any one of claims 1 to 8, wherein the carrier has a layer thickness in the range of 30 µm to 250 µm.

10. A method according to any one of claims 1 to 9, wherein the coating of the carrier with the compositions (i) and (ii) in steps (a) and (b) is carried out by means of a gravure roller, a doctor blade, or slot dies.

11. A method according to any one of claims 1 to 10, wherein the coating of the substrate with the compositions (i) and (ii) in steps (a) and (b) is carried out in parallel or sequentially.

12. A method according to any one of claims 1 to 11, wherein the curing in step (c) is carried out by UV / VIS / NIR irradiation with a wavelength in the range of 200 nm to 1100 nm.

13. A method according to any one of claims 1 to 12, wherein the method further comprises (d) the formation of the holographic-optical element by spatially resolved exposure.

14. A method according to claim 13, wherein the spatially resolved exposure according to step (d) for the formation of the holographic-optical element is carried out before the curing of the photopolymer film according to step (c).

15. A method according to any one of claims 1 to 14, wherein the photopolymer film resulting from steps (a) to (c), optionally including step (d), has a layer thickness on the substrate in the range of 0.1 µm to 100 µm. 16.A carrier with a photopolymer film coating, wherein the photopolymer film is suitable in a partial area of ​​its total surface to form a holographic-optical element.

17. A carrier according to claim 16, obtainable by the method according to any one of claims 1 to 15.

18. Laminated glass comprising the coated carrier according to claim 16 or 17.

19. Use of a laminated glass according to claim 18 for building glazing or as a (windshield) screen for a motor vehicle.

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