Method for preparing photo-orientable polymeric materials and compositions

Abstract

The present invention relates to a novel method for preparing photoalignable polymeric materials comprising aryl acrylic ester groups, to photoalignment compositions obtainable by this method, to the use of the compositions as alignment layers for liquid crystals, and to unstructured and structured optical, electrooptical, multilayer systems or nanoelectronics elements comprising the compositions.

Description

[Technical field]

[0001] The present invention relates to a method for the synthesis of photoalignable homopolymeric materials comprising aryl acrylic ester groups, to photoalignment compositions obtainable by this method, to the use of said compositions as alignment layers for liquid crystals for the manufacture of unstructured and structured optical elements, nanoelectrical or electrooptical elements and multilayer systems, and to unstructured and structured optical elements, nanoelectrical or electrooptical elements, multilayer systems and variable transmittance films comprising said compositions. [Background technology]

[0002] US 6,107,427 describes photo-alignable polymeric materials and compositions containing aryl acrylic acid esters and amides, and their synthesis. However, this synthesis method requires the use of very expensive extracts and the use of toxic materials and additives. Furthermore, the synthesis method is cumbersome, the yield is moderate, and the final product is very difficult to isolate.

[0003] In order to overcome the shortcomings of the prior art, the inventors of the present invention provide a compound having the formula (I):

[0004] [ka] [In the formula, M 1 means a repeating monomer unit from the group consisting of acrylate, methacrylate, 2-chloroacrylate, 2-phenylacrylate, acrylamide, methacrylamide, 2-chloroacrylamide, 2-phenyl-acrylamide, N-lower alkyl substituted acrylamide, N-lower alkyl substituted methacrylamide, N-lower alkyl substituted 2-chloroacrylamide, N-lower alkyl substituted 2-phenylacrylamide, vinyl ether, vinyl ester, styrene, diamine, amide, imide, siloxane, amide ester, and amic acid; S 1 is a spacer unit; and Ring A represents phenylene which is unsubstituted or optionally substituted by fluorine, chlorine, cyano, alkyl or alkoxy, or represents pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, cyclohexane-1,4-diyl, piperidine-1,4-diyl or piperazine-1,4-diyl; Ring B represents phenylene which is unsubstituted or optionally substituted by fluorine, chlorine, cyano, alkyl or alkoxy, or represents pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4- or 2,6-naphthylene, 1,3-dioxane-2,5-diyl or cyclohexane-1,4-diyl; Ring C is unsubstituted or optionally substituted phenylene with fluorine, chlorine, cyano, alkyl or alkoxy, or pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thiophenylene, 2,5-furanylene, 1,4- or 2,6-naphthylene; Y 1 , Y 2 are each independently a single covalent bond, -(CH2) t -, -O-, -CO-, -CO-O-, -O-OC-, -CF2O-, -OCF2-, -NR 4 -, -CO-NR 4 -, -R 4 N-CO-, -(CH2) u O-, -O-(CH2) u -, -(CH2) u -NR 4 -OR-NR 4 -(CH2) u - means, where R 4 means hydrogen or lower alkyl; t is an integer from 1 to 4; u represents an integer from 1 to 3; m and n each represent an integer of 0 to 4; Z is -O- or NR 5 - where R 5 means hydrogen or lower alkyl, or the second group of formula D; and In the present invention, we have found a new method for synthesizing aryl acrylate photoalignable polymeric materials containing repeating structural units of the formula: D is hydrogen or a linear or branched alkylene group having 1 to 20 carbon atoms which is optionally substituted at least once with a halogen or at least one siloxane moiety, or a cycloalkyl residue having 3 to 8 ring atoms which is optionally substituted with at least one halogen, alkyl or alkoxy.

[0005] The method for preparing the aryl acrylic acid ester photo-alignable polymer material includes the following steps a to d: a. Formula (II):

[0006] [ka] [In the formula, Y is either CR' or O; and When Y is CR', then q=1 and R=COOR"; where R' and R" are each independently hydrogen or a linear or branched alkylene radical having 1 to 20 carbon atoms, optionally substituted at least once with a halogen or at least one siloxane moiety, or a cycloalkyl residue having 3 to 8 ring atoms, optionally substituted with at least one halogen, alkyl or alkoxy; or If Y is O, then q=0; and Ring C has the same meaning as above, Formula (III):

[0007] [ka] [In the formula, M 1 , S 1 , Ring A, Y 1 , ring B and Y 2 , n and m are as defined above], and optionally a compound represented by formula (IV) or (IV'):

[0008] [ka] with a compound represented by the formula: b. Optionally, reacting the compound obtained in step a with a compound of formula (V):

[0009] [ka] [Wherein, X is OH, F, Cl or I; Z and Z' are each independently either H or halogen; q and q' are each independently an integer of 0 to 2; p is an integer from 0 to 10; r and r' are each independently an integer of 0 to 3; c. polymerizing the compound obtained under step a or b with organic or inorganic peroxides; d. Stopping the reaction by heating or using a radical inhibitor or scavenger. Includes.

[0010] Preferably, in the preparation method of the aryl acrylic acid ester photo-orientable polymer material of the present invention, the compound of formula (II) is: Y is CR'; and Ring C is unsubstituted or substituted with alkoxy, preferably methoxy, ethoxy, propoxy. and in the compound of formula (III), n=0 and m=1.

[0011] The reaction of a compound of formula (II) with a compound of formula (III) takes place, for example, in the presence of a base, typically triethylamine, and a catalytic amount of dimethylaminopyridine (DMAP), in solution in a solvent such as toluene.

[0012] The polymer obtained by said process no longer requires further purification steps and can be formulated and used directly.

[0013] It is therefore an object of the present invention to provide a novel process for the synthesis of aryl acrylate photoorientable polymeric materials comprising recurring structural units of formula (I), compounds obtainable by said process, compositions comprising such compounds, the use of such compositions for the orientation of liquid crystals in unstructured and structured optical elements, electro-optical elements, multilayer systems and nano-electrical devices, and unstructured and structured optical or electro-optical elements, multilayer systems and variable transmittance films comprising said compositions.

[0014] The process disclosed above can be stopped at any time by heating to decompose the organic or inorganic peroxides, thereby terminating the polymerization. Heating can be carried out via methods known in the art, such as oil bath, sand bath, jacketed heating system, double mantle vessel, infrared conveyor, microwave, etc. The polymerization process can be stopped, for example, when the polymer reaches a desired length or molecular weight. Additionally, the process can be stopped by using radical inhibitors or radical scavengers.

[0015] The final product does not need to be further purified. Thus, the polymer solution may still contain unreacted monomers or the polymer solution may not contain unreacted monomers. It is also an object of the present invention to provide a composition comprising a polymer comprising repeating structural units of formula (I) and unreacted monomers of formula (I) in a ratio of 50 / 50, more preferably in a ratio of 75 / 25, even more preferably in a ratio of 80 / 20, or in a ratio of 90 / 10, even more preferably in a ratio of >90 / <10.

[0016] However, if a robust process is envisaged, independent of variations in exposure energy, it is also an object of the present invention to provide a composition comprising a polymer comprising a repeating structural unit of formula (I) and an unreacted monomer of formula (I) in a ratio of >90 / <10, more preferably in a ratio of 90 / 10, even more preferably in a ratio of 80 / 20 or 75 / 25, even more preferably in a ratio of 50 / 50.

[0017] Moreover, it has been surprisingly found in the present invention that as the amount of monomer compound in the photoalignment composition is increased, a variety of tilt angles are available, independent of the exposure energy.

[0018] Furthermore, it has been surprisingly found in the present invention that as the amount of monomer compound in the photoalignment composition increases, the resulting alignment layer and the alignment layer coated with the liquid crystal polymer become more robust to deviations and variations in exposure energy.

[0019] Since the process only produces polymers containing one type of monomer, the end product of such a reaction is a homopolymer or a composition containing both unreacted monomer and homopolymer.

[0020] The term "linking group" as used in connection with the present invention means -O-, -CO-, -CO-O-, -O-CO-, a group of the formula:

[0021] [ka] a group represented by -NR 1 -, -NR 1 -CO-, -CO-NR 1 -, -NR 1 -CO-O-, -O-CO-NR 1 -, -NR 1 -CO-NR 1 -, -CH=CH-, -C≡C-, -O-CO-O-, and -Si(CH3)2-O-Si(CH3)2-, R 1represents a hydrogen atom or a C1-C6 alkyl, with the proviso that the oxygen atoms of the linking groups are not directly linked to each other.

[0022] As used in the context of the present invention, the term "spacer unit" refers to a cyclic, linear or branched, substituted or unsubstituted C-C alkylene unit in which one or more, preferably non-adjacent, -C-, -CH-, -CH2- groups may be replaced by a linking group as defined above. 24 It is alkylene.

[0023] In the context of the present invention, the term "alkyl" refers to a substituted or unsubstituted, linear or branched, saturated hydrocarbon residue having up to 20 carbon atoms, in which one or more -CH2- or -CH3 groups are unsubstituted or may be replaced by at least one linking group as defined above, or / and an alicyclic or / and aromatic group.

[0024] The terms "lower alkyl" and similarly "lower alkoxy", "hydroxy lower alkyl", "phenoxy lower alkyl", "phenyl lower alkyl" mean a straight-chain or branched saturated hydrocarbon residue having 1 to 6, preferably 1 to 3, carbon atoms, such as methyl, ethyl, propyl or i-propyl, as defined hereinbefore and hereinafter.

[0025] The terms "alkyl" and similarly "alkoxy" refer to saturated straight-chain or branched hydrocarbon residues having up to 20 carbon atoms, as defined hereinbefore and hereinafter.

[0026] The "alkyl" or "alkoxy" substituents are hydroxy, fluorine, chlorine, cyano, ether, ester, amino, amide, alicyclic or aromatic groups, in which one or more -CH2- groups may be replaced by at least one linking group, respectively.

[0027] In the context of the present invention, "straight chain alkyl" is, for example, but not limited to, methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosyl, henicosyl, docosyl, tricosyl or quatrocosyl.

[0028] In the context of the present invention, "alicyclic group" means, for example, a substituted or unsubstituted non-aromatic carbocyclic or heterocyclic group, and represents, for example, a ring system having 3 to 30 carbon atoms, such as cyclopropane, cyclobutane, cyclopentane, cyclopentene, cyclohexane, cyclohexene, cyclohexadiene, decalin, adamantane, tetrahydrofuran, dioxane, dioxolane, pyrrolidine, piperidine or a steroid skeleton such as cholesterol, where the substituents are preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, more preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, and most preferably methyl, ethyl, propyl. Preferred alicyclic groups are cyclopentane, cyclopentene, cyclohexane, cyclohexene, and more preferably cyclopentane or cyclohexane.

[0029] In the context of the present invention, "aromatic group" means, for example, furan, benzene or phenylene, pyridine, pyrimidine, naphthalene, preferably of 5, 6, 10 or 14 ring atoms, and may form ring assemblies, such as biphenylene or triphenylene, uninterrupted or interrupted by at least one heteroatom and / or at least one linking group; or may form condensed polycyclic ring systems, such as phenanthrene or tetralin. Preferably, the aromatic group is benzene, phenylene, biphenylene or triphenylene. More preferred aromatic groups are benzene, phenylene and biphenylene. Most preferred is phenylene.

[0030] The term "phenylene which is unsubstituted or optionally substituted by fluorine, chlorine, cyano, alkyl or alkoxy" encompasses within the scope of the present invention 1,2-, 1,3- or 1,4-phenylene, but in particular 1,3- or 1,4-phenylene which is unsubstituted or mono- or polysubstituted by fluorine, chlorine, cyano, alkyl or alkoxy, preferably by fluorine, methyl, ethyl, propyl, butyl, methoxy, ethoxy, propoxy, butoxy or cyano. Particularly preferred is the 1,4-phenylene residue. Examples of preferred phenylene residues are 1,3- or 1,4-phenylene, 4- or 5-methyl-1,3-phenylene, 4- or 5-methoxy-1,3-phenylene, 4- or 5-ethyl-1,3-phenylene, 4- or 5-ethoxy-1,3-phenylene, 2- or 3-methyl-1,4-phenylene, 2- or 3-ethyl-1,4-phenylene, 2- or 3-propyl-1,4-phenylene, 2- or 3-butyl-1,4-phenylene, 2- or 3-methoxy-1,4-phenylene, 2- or 3-ethoxy-1,4-phenylene, 1,4-phenylene, 2- or 3-propoxy-1,4-phenylene, 2- or 3-butoxy-1,4-phenylene, 2,3-, 2,6- or 3,5-dimethyl-1,4-phenylene, 2,6- or 3,5-dimethoxy-1,4-phenylene, 2- or 3-fluoro-1,4-phenylene, 2,3-, 2,6- or 3,5-difluoro-1,4-phenylene, 2- or 3-chloro-1,4-phenylene, 2,3-, 2,6- or 3,5-dichloro-1,4-phenylene, 2- or 3-cyano-1,4-phenylene, and the like.

[0031] In a preferred embodiment, S 1 is a spacer unit, where m and n are 0, the spacer unit is S 2 and when at least one of m or n is 1, the spacer unit is S 3 and; Here, S 2 and S 3 is an unsubstituted or unsubstituted straight or branched chain, -(CH2) r- and even - (CH2) r -O-, -(CH2) r -O-(CH2) s -, -(CH2) r -O-(CH2) s -O-, -(CH2) r -CO-, -(CH2) r -CO-O-, -(CH2) r -O-CO-, -(CH2) r -NR 2 -, -(CH2) r -CO-NR 2 -, -(CH2) r -NR 2 -CO-, -(CH2) r -NR 2 -CO-O- or -(CH2) r -NR 2 -CO-NR 3 - and optionally C1-C 24 - mono- or poly-substituted with alkyl, hydroxy, fluorine, chlorine, cyano, ether, ester, amino, amido; and wherein one or more -CH2- groups may be replaced by a linking group, an alicyclic or aromatic group; and Here, r and s are each an integer from 1 to 20 (wherein S 2 If r+s is 3≦r+s≦24, then S 3 for 6≦r+s≦24; and R 2 and R 3 each independently represents hydrogen or lower alkyl.

[0032] In a further preferred embodiment of the present invention, S 2 Or S 3 is a substituted or unsubstituted, linear or branched, -(CH2) r - and even - (CH2) r -O-, -(CH2) r -O-(CH2) s -, -(CH2) r -O-(CH2) s -O-, -(CH2) r -CO-, -(CH2)r -CO-O-, -(CH2) r -O-CO-, -(CH2) r -NR 2 -, -(CH2) r -CO-NR 2 -, -(CH2) r -NR 2 -CO-, -(CH2) r -NR 2 -CO-O- or -(CH2) r -NR 2 -CO-NR 3 where R 2 and R 3 each independently represents hydrogen or lower alkyl; preferably, S 2 Or S 3 In some cases, C1-C 24 -Alkyl, preferably C1-C 12 -alkyl, more preferably C1-C8-alkyl, where alkyl has the abovementioned meanings and preferences, or 2 Or S 3 is optionally mono- or polysubstituted with hydroxy, fluorine, chlorine, cyano, ether, ester, amino, amido; and wherein one or more -CH2- groups may be replaced by a linking group, an alicyclic or / and aromatic group; Here, S 2 where the single suffix "r" is an integer between 4 and 24, preferably between 5 and 12, and more preferably between 5 and 8, in particular 6 or 8; and S 3 where the single suffix "r" is an integer between 8 and 24, preferably between 8 and 12, and in particular 8, 9, 10, 11 or 12; and Here, S 2 where the sum of the suffixes "r and s" is an integer between 1 and 24, preferably between 2 and 12, and more preferably between 5 and 8; and Here, S 3 where the sum of the suffixes "r and s" is an integer between 8 and 24, preferably between 8 and 12, and in particular 8, 9, 10, 11 or 12; and R2 and R 3 each independently represents hydrogen or lower alkyl.

[0033] In the most preferred embodiment of the present invention, S 2 Or S 3 is an unsubstituted or unsubstituted straight or branched chain, -(CH2) r - and even - (CH2) r -O-, -(CH2) r -O-(CH2) s -, -(CH2) r -O-(CH2) s -O-, -(CH2) r -CO-, -(CH2) r -CO-O-, -(CH2) r -O-CO-, especially -(CH2) r -O-, -(CH2) r -O-(CH2) s -, -(CH2) r -O-(CH2) s -O-, -(CH2) r -CO-, -(CH2) r -CO-O-, -(CH2) r -O-CO-, more particularly -(CH2) r -O- and optionally C1-C 24 -Alkyl, preferably C1-C 12 -alkyl, more preferably C1-C8-alkyl, or mono- or polysubstituted with hydroxy, fluorine, chlorine, cyano, ether, ester, amino, amido; and where one or more -CH2- groups may be replaced by a linking group or an alicyclic or aromatic group; and where the individual suffixes r and s and the sum of the suffixes s and r have the above meanings and preferences; and R 2 and R 3 each independently represents hydrogen or lower alkyl.

[0034] Preferably, S 2 , S 3 The alkylene substituents in 24-Alkyl, preferably C1-C 12 -alkyl, more preferably C1-C8-alkyl, hydroxy, fluorine, chlorine, cyano, ether, ester, amino or amido.

[0035] Preferred "spacer units" S 2 Examples are 1,6-hexylene, 1,7-heptylene, 2-methyl-1,2-propylene, 1,3-butylene, ethyleneoxycarbonyl, ethyleneoyloxy, propyleneoxy, propyleneoxycarbonyl, propyleneoyloxy, butyleneoxy, butyleneoxycarbonyl, butyleneoyloxy, propyleneamino, butyleneamino, pentyleneamino, hexyleneamino, heptyleneamino, ethyleneaminocarbonyl, propyleneaminocarbonyl, butyleneaminocarbonyl, ethylenecarbonylamino, propyleneaminocarbonyl ... Preferred are propylenecarbonylamino, butylenecarbonylamino, pentylenecarbonylamino, hexylenecarbonylamino, heptylenecarbonylamino, pentyleneaminocarbonyl, hexyleneaminocarbonyl, heptyleneaminocarbonyl, pentyleneoxy, pentyleneoxycarbonyl, pentyleneoyloxy, hexyleneoxy, hexyleneoxycarbonyl, hexyleneoyloxy, heptyleneoxy, heptyleneoxycarbonyl, and heptyleneoyloxy, and particularly preferred is hexyleneoxy.

[0036] Preferred "spacer units" S 3Examples of the aryloxy group include 1,8-octylene, 1,9-nonylene, 1,10-decylene, 1,11-undecylene, 1,12-dodecylene, 9-nonyleneoxy, 11-undecyleneoxy, 12-dodecyleneoxy, 11-undecyleneoxycarbonyl, 12-dodecyleneoxycarbonyl, 9-nonyleneoxycarbonyl, 11-undecyleneoyloxy, 12-do ... Examples of such amino acids include dodecyleneoyloxy, 9-nonyleneoyloxy, 11-undecyleneamino, 12-dodecyleneamino, 9-nonyleneamino, 11-undecyleneaminocarbonyl, 12-dodecyleneaminocarbonyl, 9-nonyleneaminocarbonyl, 11-undecylenecarbonylamino, 12-dodecylenecarbonylamino, and nonylenecarbonylamino.

[0037] Particularly preferred "spacer units" S 2 is -(CH2) r -, where r is 6 or 8, and also -(CH2) r -O-, -(CH2) r -CO-O- and -(CH2) r -O-CO-.

[0038] Furthermore, particularly preferred "spacer units" S 3 is -(CH2) r -, where r is 8, 9, 10, 11, or 12, as well as -(CH2) r -O-, -(CH2) r -CO-O- and -(CH2) r -O-CO-.

[0039] In the context of the present invention, the term "halogenated" means that the photo-alignable polymeric material containing aryl acrylic ester groups contains one or more halogen atoms, preferably two halogen atoms, more preferably three halogen atoms. The present invention includes that the halogen atoms are all bonded to the same carbon atom or to different carbon atoms. It also includes that the same molecule may be halogenated by different halogen atoms. The halogen atoms are fluorine, chlorine, bromine or iodine.

[0040] In the context of the present invention, a "siloxane moiety" means any substituent that contains a functional group having at least a Si-O-Si bond. The photoalignable polymeric material of the present invention may contain one or more siloxane moieties.

[0041] Further preferred is a compound represented by the formula (I): M 1 are acrylate, methacrylate and styrene derivatives; Ring A represents unsubstituted or optionally substituted phenylene with fluorine, chlorine, cyano, alkyl or alkoxy, or represents pyridine-2,5-diyl, pyrimidine-2,5-diyl, cyclohexane-1,4-diyl; Ring B represents unsubstituted or optionally substituted phenylene with fluorine, chlorine, cyano, alkyl or alkoxy, or represents pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4- or 2,6-naphthylene, cyclohexane-1,4-diyl; Y 1 , Y 2 each independently represent a single covalent bond, -CHCH-, -O-, -CFO-, -OCF-, -CH-O-, -O-CH-, -CO-O-, or -O-OC-; Ring C denotes phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, preferably methoxy, ethoxy or propoxy, or denotes pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-furanylene, 1,4- or 2,6-naphthylene; Z means -O-, and S 1 , D, m and n have the above meanings].

[0042] More preferably, the compound represented by formula (I) M 1 is a monomer unit selected from the group consisting of acrylate, methacrylate; Ring A is unsubstituted phenylene or phenylene substituted with alkyl or alkoxy; Ring B is unsubstituted phenylene or phenylene substituted with fluorine, alkyl or alkoxy; Y 1 , Y 2 are each independently a single covalent bond, -CO-O- or -O-OC-; Ring C is unsubstituted phenylene or phenylene substituted with alkyl or alkoxy, preferably methoxy; Z is -O-; and S 1 , D, m and n have the above meanings].

[0043] The method for preparing an aryl acrylate photo-alignable polymer material containing a repeating structural unit of formula (I) comprises steps a to d as described above. Step a of the method of the present invention preferably occurs in the presence of a compound of formula (IV) or (IV') when Y=O and m=0. When Y=C, a compound of formula (IV) or (IV') is not required in step a of the method of the present invention.

[0044] In a preferred embodiment, the compound of formula (III) is characterized by: M 1 is a monomer unit selected from the group consisting of acrylate, methacrylate; Ring A is unsubstituted phenylene or phenylene substituted with alkyl or alkoxy; Ring B is unsubstituted phenylene or phenylene substituted with fluorine, alkyl or alkoxy; Y 1 , Y 2 are each independently a single covalent bond, -CO-O-, or -O-OC-; m and n each independently represent 0 or 1; S 1 is as stated above.

[0045] The reaction of a compound of formula (II) with a compound of formula (III) takes place, for example, in the presence of a base, typically triethylamine, and a catalytic amount of dimethylaminopyridine (DMAP), in solution in a solvent such as toluene.

[0046] In one embodiment, step b of the method of the present invention is carried out when the compound of formula (I) is terminally halogenated or substituted with a siloxane moiety, i.e. D is at least one halogenated or contains one or more siloxane moieties, C1-C 12 This occurs when the alkylene chain is linear or branched.

[0047] The conditions for the synthesis of the aryl acrylate photoalignable polymeric material containing the repeating structural unit of formula (I) of the present invention are well known to those skilled in the art.

[0048] In further embodiments, the present invention also relates to compounds obtainable by the above process and to compositions obtainable by the above process.In further embodiments, the present invention relates to formulations or / and blends comprising a compound of formula (I) obtainable by the above process as a homopolymer and / or as a monomer or a composition obtainable by the above process and optionally a solvent.

[0049] Preferably, the formulation comprises further solvents, in particular aprotic or protic polar solvents such as γ-butyrolactone, N,N-dimethylacetamide, N-methylpyrrolidone or N,N-dimethylformamide, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), 3-pentanone, cyclopentanone, cyclohexanone, ethyl acetate, n-butyl acetate, 1-methoxypropyl acetate (MPA), alcohols, isopropanol, n-butanol, butan-2-ol, in particular 1-methoxypropanol (MP). Preferred are aprotic polar solvents, in particular γ-butyrolactone, N,N-dimethylacetamide, N-methylpyrrolidone or N,N-dimethylformamide, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), 3-pentanone, cyclopentanone, cyclohexanone, ethyl acetate, n-butyl acetate, 1-methoxypropyl acetate (MPA).

[0050] The homopolymer of formula (I) or the compound obtained by the above method has a molecular weight MW of 10,000 to 10,000,000, preferably 20,000 to 900,000, more preferably 50,000 to 500,000, even more preferably 75,000 to 400,000, and particularly preferably 100,000 to 300,000.

[0051] (M 1 ) is represented by the following formula:

[0052] [ka] acrylates such as those represented by the formula:

[0053] [ka] acrylamide, such as represented by the formula:

[0054] [ka] Vinyl ethers and vinyl esters, such as those represented by the formula:

[0055] [ka] styrene derivatives, such as those represented by the following formula:

[0056] [ka] wherein: R 1 means hydrogen or lower alkyl.

[0057] (M 1 Preferred examples of ) are acrylates, methacrylates, 2-chloroacrylates, acrylamides, methacrylamides, 2-chloro-acrylamides, styrene derivatives and siloxanes.

[0058] Acrylates, methacrylates, styrene derivatives and siloxanes are particularly preferred (M 1 ).

[0059] Particularly highly preferred (M 1 ) are acrylate, methacrylate and styrene derivatives.

[0060] Particularly preferred are homopolymeric materials comprising aryl acrylate photoalignable polymeric materials comprising repeating structural units of formula (I) where n=0 and m=1, M 1 are acrylate, methacrylate and styrene derivatives; Ring B represents unsubstituted or optionally substituted phenylene with fluorine, chlorine, cyano, alkyl or alkoxy, or represents pyridine-2,5-diyl, pyrimidine-2,5-diyl, cyclohexane-1,4-diyl; Y 2 means a single covalent bond, -CO-O- or -O-OC-; S 3 is a substituted or unsubstituted, linear or branched, -(CH2) r - and even - (CH2) r -O-, -(CH2) r -O-(CH2) s -, -(CH2) r -O-(CH2) s -O-, -(CH2) r -CO-, -(CH2) r -CO-O-, -(CH2) r -O-CO-, -(CH2) r -NR 2 -, -(CH2) r -CO-NR 2 -, -(CH2) r -NR 2 -CO-, -(CH2) r -NR 2 -CO-O- or -(CH2) r -NR 2 -CO-NR 3 where the suffix "r" is an integer between 8 and 24, preferably between 8 and 12, in particular 8, 9, 10, 11 or 12; and Ring C denotes phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, preferably methoxy, ethoxy or propoxy, or denotes 1,4- or 2,6-naphthylene; Z means -O-; and D is a C1-C3 straight or branched alkylene chain that is optionally halogenated at least once or contains one or more siloxane moieties.

[0061] Also preferred is a composition comprising a compound of formula (I), wherein M 1 , S 1 , m and n are as defined above; and Ring A represents unsubstituted or optionally substituted phenylene with fluorine, chlorine, cyano, alkyl or alkoxy, or represents pyridine-2,5-diyl, pyrimidine-2,5-diyl, cyclohexane-1,4-diyl; Ring B represents phenylene which is unsubstituted or optionally substituted by fluorine, chlorine, cyano, alkyl or alkoxy, or represents pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4- or 2,6-naphthylene or cyclohexane-1,4-diyl; Y 1 , Y 2 each independently represent a single covalent bond, -CHCH-, -O-, -CH-O-, -O-CH-, -OCF-, -CFO-, -CO-O-, or -O-OC-; Ring C denotes phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, preferably methoxy, ethoxy or propoxy, or denotes pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-furanylene or 1,4- or 2,6-naphthylene; Z means -O-; and D is a C1-C3 straight or branched alkylene chain that is optionally halogenated at least once or contains one or more siloxane moieties.

[0062] In the context of the present invention, the above method is used to synthesize homopolymeric materials, including aryl acrylate photoalignable polymeric materials, comprising repeating structural units of formula (I), where: M 1 , S 1and m, n are as defined above; and Ring A represents unsubstituted or optionally substituted phenylene with fluorine, chlorine, cyano, alkyl or alkoxy, or represents pyridine-2,5-diyl, pyrimidine-2,5-diyl, cyclohexane-1,4-diyl; Ring B represents phenylene which is unsubstituted or optionally substituted by fluorine, chlorine, cyano, alkyl or alkoxy, or represents pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4- or 2,6-naphthylene or cyclohexane-1,4-diyl; Y 1 , Y 2 each independently represent a single covalent bond, -CHCH-, -O-, -CH-O-, -O-CH-, -CO-O-, -O-OC-, -CF-O-, or -O-CF-; Ring C denotes phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, preferably methoxy, or denotes pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-furanylene or 1,4- or 2,6-naphthylene; Z means -O-; and D is a C1-C3 straight or branched alkylene chain that is optionally halogenated at least once or that optionally contains one or more siloxane moieties.

[0063] Particularly preferred are homopolymeric materials comprising aryl acrylate photoalignable polymeric materials comprising repeating structural units of formula (I), where n is 0; and M 1 and S 1 is as defined above; and Ring B represents phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, or represents pyridine-2,5-diyl, pyrimidine-2,5-diyl or cyclohexane-1,4-diyl; Y 2means a single covalent bond, -CO-O- or -O-OC-; m means 0 or 1; Ring C denotes phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, preferably methoxy, ethoxy or propoxy, or denotes 1,4- or 2,6-naphthylene; Z means -O-; and D is a C1-C3 straight or branched alkylene chain that is optionally halogenated at least once or that optionally contains one or more siloxane moieties; preferably D is methyl, ethyl or propyl.

[0064] For polymerization, the repeating structural units are first prepared separately from the individual components as described above. The formation of the polymer then takes place in a manner known per se under the influence of ultraviolet light or heat, or preferably by the action of a radical initiator or an inorganic or organic peroxide or ionic initiator. The radical initiator can be, for example, an azo-based initiator such as azobisisobutyronitrile (AIBN), azobismethylbutyronitrile (AMBN), 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH), 1,1'-azobis(cyanocyclohexane) (ACHN), 4,4'-azobis(4-cyanovaleric acid) (ACVA) and similar compounds. Examples of inorganic peroxides are sodium persulfate, potassium persulfate or ammonium persulfate. Examples of organic peroxides are tert-butyl peroxide, dicumyl peroxide, lauryl peroxide or peroxycarbonate. Examples of commercially available peroxides are, but are not limited to, Luperox® LP (dilauryl peroxide), Luperox® DI (di-tert-butyl peroxide) or Perkadox® IPP (diisopropyl peroxydicarbonate). Ionic initiators are alkaline organic compounds such as phenyllithium or naphthylsodium, or Lewis acids such as BF3, AlCl3, SnCl3 or TiCl4. This list is not exhaustive and other initiators are also contemplated in the context of the present invention. The monomers can be polymerized in solution, suspension, emulsion or by precipitation, but are not limited to this.

[0065] The solvents used in the preparation of the polymers of the present invention are the same as those described above.

[0066] The composition comprising the compound of formula (I) obtained by the process of the invention or the composition comprising a homopolymer comprising a repeating structural unit of formula (I) and at least one monomer of formula (I) can be further mixed with other photoalignable or non-photoalignable polymers, copolymers, oligomers or monomers.

[0067] The composition comprising a compound of formula (I) or a composition comprising a homopolymer comprising a repeating structural unit of formula (I) and at least one monomer of formula (I) obtained by the process of the invention may further comprise a solvent and / or an additive, -silane-containing compounds and / or -epoxy-containing crosslinking agent or / and -thiol-containing compounds and / or photoactive additives, such as photosensitizers or photoradical generators, or / and cationic photoinitiators, or / and - surfactants and / or emulsifiers and / or -Antioxidants and / or -Leveling agent and / or -polymerizable liquid crystals, or / and -functional (meth)acrylates, or / and -Curing compounds It may further contain etc.

[0068] Suitable silane-containing additives are described in Plast. Eng. 36 (1996), (Polyimides, fundamentals and applications), Marcel Dekker, Inc.

[0069] Suitable epoxy-containing crosslinking additives include 4,4'-methylene-bis-(N,N-diglycidylaniline), trimethylolpropane triglycidyl ether, benzene-1,2,4,5-tetracarboxylic acid 1,2,4,5-N,N'-diglycidyldiimide, polyethylene glycol diglycidyl ether, N,N-diglycidylcyclohexylamine, and the like.

[0070] Suitable thiol-containing compounds include ethylene glycol bis(3-mercaptobutyrate), 1,2-propylene glycol(3-mercaptobutyrate), trimethylolpropane tris(3-mercaptobutyrate), ethylene glycol bis(2-mercaptoisobutyrate), 1,2-propylene glycol bis(2-mercaptoisobutyrate) or trimethylolpropane tris(2-mercaptoisobutyrate), pentaerythritol tetrakis(3-mercaptobutyrate), 1,3,5-tris(3-mercaptobutyrate), Examples of highly functionalized polythiols include pentaerythritol tetrakis(3-mercaptopropionate) (PETMP), trimethylolpropane tris(3-mercaptopropionate) (TMPTMP), and the like.

[0071] Suitable photoactive additives include 2,2-dimethoxyphenylethanone, mixtures of diphenylmethanone with N,N-dimethylbenzenamine or ethyl 4-(dimethylamino)benzoate, xanthones, thioxanthones, Irgacure® 184, 369, 500, 651 and 907 (BASF), Michler's ketone, triarylsulfonium salts, and the like.

[0072] Functional (meth)acrylates can be used in certain devices that are well known to those skilled in the art. Such functional (meth)acrylates can be monofunctional and belong to the cyanophenyl or cyanobenzyl-containing (meth)acrylates. Examples are cyanophenyl-benzoate-acrylate, cyanobiphenyl-acrylate or 4-(6-prop-2-enoyloxyhexoxy)benzoic acid (4-cyanophenyl).

[0073] The curable compounds are both organic and inorganic compounds, which do not contain photo-orientable moieties. The curable compounds are used to flatten a surface or a substrate to reduce surface unevenness, to make the surface or substrate harder, to increase resistance to scratches, or to increase resistance to mechanical or chemical abrasion. Such curable compounds include polymers, dendrimers, oligomers, prepolymers, and monomers, which may be polymerized either by radiation or heat. Examples of suitable polymer types are, but are not limited to, polyalkylenes (polyethylene, polypropylene, etc.), polycycloolefins COP / COC, polybutadienes, poly(meth)acrylates, polyesters, polystyrenes, polyamides, polyethers, polyurethanes, polyimides, polyamic acids, polycarbonates, polyvinyl alcohols, polyvinyl chlorides, cellulose, and cellulose derivatives such as cellulose triacetate. Examples of suitable monomer types are mono- and multifunctional (meth)acrylates, epoxies, isocyanates, allyl derivatives, and vinyl ethers.

[0074] It is encompassed by the present invention that the curable compound may be added to the composition comprising the compound of formula (I) obtained by the method of the present invention, or to the composition comprising the homopolymer comprising a repeating structural unit of formula (I) and at least one monomer of formula (I).It is also encompassed by the present invention that the curable compound may be added as a layer below or above the alignment layer of the present invention.

[0075] The present invention also relates to the use of a composition comprising a compound of formula (I) obtainable by the inventive method or a composition comprising a homopolymer comprising recurring structural units of formula (I) and at least one monomer of formula (I) for preparing an alignment layer for liquid crystals.

[0076] The present invention further relates to a method for preparing an alignment layer for liquid crystals, comprising irradiating a composition comprising a compound of formula (I) obtainable by the inventive method of the present invention or a composition comprising a homopolymer comprising recurring structural units of formula (I) and at least one monomer of formula (I) with aligning light.

[0077] Preferably, the method comprises: - applying to a support a composition comprising a compound of formula (I) obtained by the process of the invention or a composition comprising a homopolymer comprising recurring structural units of formula (I) and at least one monomer of formula (I), - then irradiating with aligning light a composition comprising a compound of formula (I) obtained by the method of the invention or a composition comprising a homopolymer comprising a recurring structural unit of formula (I) and at least one monomer of formula (I).

[0078] Particularly preferred is a method in which two irradiation processes are carried out, one with aligning light and the other with or without aligning light, such as isotropic light.

[0079] The term "carrier" as used in the context of the present invention refers to, but is not limited to, a preferably transparent or non-transparent, birefringent or non-birefringent, preferably glass or plastic substrate, a polymer film (such as polyethylene naphthalate (PEN), polyethylene terephthalate (PET), triacetyl cellulose (TAC), polypropylene, polycarbonate (PC), polymethyl methacrylate (PMMA), cycloolefin copolymer (COP)), or a silicon wafer. The carrier may be rigid or flexible and of any form or shape (such as concave or convex). The carrier may have additional layers, such as organic layers, insulating layers, or metal layers. The layers may have different functions, for example, an organic layer may be coated as a primer layer that enhances the compatibility of the material coated with the support. A metal layer (such as indium tin oxide (ITO)) may be used as an electrode or may function as a reflector, for example, when used in an electro-optical device such as a display. The carrier may also be an optical element or device with a specific function, such as a substrate for an LCD, which may include, for example, thin film transistors, electrodes, or color filters. In another example, the carrier is a device that includes an OLED layer structure.The carrier can also be, but is not limited to, a retardation film, a polarizer such as a polarizing film or sheet polarizer, a reflective polarizer such as the commercially available Vikuiti (TM) DBEF film.

[0080] Generally, the composition comprising the compound of formula (I) obtained by the method of the present invention or the composition comprising the homopolymer comprising a repeating structural unit of formula (I) and at least one monomer of formula (I) is applied by the common coating and printing methods known in the art, such as spin coating, air doctor coating, blade coating, knife coating, kiss roll coating, cast coating, slot orifice coating, calendar coating, die coating, dipping, brushing, casting with a bar, roller coating, flow coating, wire coating, spray coating, dip coating, whirler-coating, cascade coating, curtain coating, air knife coating, gap coating, rotary screen, reverse roll coating, gravure coating, metering rod (Meyer bar) coating, slot die (extrusion) coating, hot melt coating, roller coating, flexo coating, electrocoating.

[0081] Printing methods are, for example, silk screen printing, relief printing such as flexographic printing, inkjet printing, intaglio printing such as direct gravure printing or offset gravure printing, lithographic printing such as offset printing, or stencil printing such as screen printing.

[0082] The carrier may be moved during deposition of the photoalignable polymeric material, or of the composition comprising a compound of formula (I) obtained by the inventive method of the present process, or of the composition comprising a homopolymer comprising a repeating structural unit of formula (I) and at least one monomer of formula (I), and / or of the photoalignable material, for example when the production is carried out in a continuous roll-to-roll process.

[0083] In the context of the present invention, the term "orientation light" is intended to mean light that can induce anisotropy in the photo-orientable material and can be partially linearly or elliptically polarized or unpolarized and / or incident on the surface of the alignment layer from any direction. The wavelength, intensity and energy of the orientation light are selected according to the photosensitivity of the photo-orientable material and the photo-orientation group. Typically, the wavelength is in the UV-A, UV-B and / or UV-C range or in the visible range. Preferably, the orientation light comprises light with a wavelength of less than 450 nm. More preferably, the orientation light comprises light with a wavelength of less than 420 nm.

[0084] The UV light is preferably selected according to the absorption of the photoalignment group, i.e. the absorption of the film should overlap with the emission spectrum of the lamp used for LP-UV irradiation, more preferably with linearly polarized UV light. The intensity and energy used are selected according to the photosensitivity of the material and according to the alignment performance of interest. In most cases, very low energies (a few mJ / cm2) are sufficient. 2 ) already leads to high alignment quality.

[0085] If the alignment light is polarized, it can be at least partially linearly polarized, elliptically polarized (e.g., circularly polarized, etc.). The alignment light can also be unpolarized. The alignment light can be exposed perpendicularly or obliquely.

[0086] If the alignment light is linearly polarized, the polarization plane of the alignment light is taken to mean the plane defined by the propagation direction and the polarization direction of the alignment light. If the alignment light is elliptically polarized, the polarization plane is taken to mean the plane defined by the propagation direction of the light and by the major axis of the polarization ellipse.

[0087] Thus, to produce an alignment layer in a region selectively limited by area, a composition comprising a compound of formula (I) obtained by the method of the invention of the present method, or a composition comprising a homopolymer comprising a repeating structural unit of formula (I) and at least one monomer of formula (I) can be applied. For example, a first prepared and spun in a spin-coating apparatus on a support (for example a glass plate coated with indium tin oxide (ITO)), optionally coated with an electrode, can be obtained to obtain a uniform layer of 0.05 to 50 μm thickness. The region to be oriented can then be exposed to, for example, a mercury high pressure lamp, a xenon lamp or a pulsed UV laser, using a polarizer and optionally a mask to form a structure. The exposure time depends on the power of the individual lamps and can vary from a few minutes to a few hours. However, the photoreaction can also be achieved by irradiating the uniform layer using, for example, a filter that passes only radiation suitable for the photoreaction.

[0088] A preferred method of the present invention relates to methods for preparing an alignment layer, in particular roll-to-roll methods, in which time is a critical parameter, in particular the exposure time is a critical parameter.

[0089] The present invention also relates to an alignment layer comprising a composition comprising a compound of formula (I) obtainable by the inventive method of the present invention, or a composition comprising a homopolymer comprising recurring structural units of formula (I) and at least one monomer of formula (I).

[0090] The use of the compositions comprising compounds of formula (I) obtainable by the inventive method or of the compositions comprising homopolymers comprising recurring structural units of formula (I) and at least one monomer of formula (I) as alignment layers for liquid crystals, and also their use in unstructured and structured optical, electro-optical and nano-electrical elements, in particular for the production of hybrid layer elements, is also an object of the present invention. They can furthermore be used in variable transmittance films.

[0091] The term "structuring" refers to changes in azimuthal orientation induced by locally changing the direction of polarized oriented light.

[0092] Furthermore, the present invention relates to an optical, electro-optical or nano-electrical device comprising a composition according to the invention.

[0093] Such optical, electro-optical or nano-electrical elements are also referred to as photo-alignable objects. Such photo-alignable objects are described in unpublished application EP 16182085.7 and published application WO 2015 / 024810, which are incorporated herein by reference.

[0094] Furthermore, the present invention relates to the use of a composition comprising a compound of formula (I) obtainable by the inventive method or a composition comprising a homopolymer comprising recurring structural units of formula (I) and at least one monomer of formula (I) as an alignment layer for orienting organic or inorganic compounds, in particular for orienting liquid crystals and liquid crystal polymers.

[0095] The alignment layer may still contain unreacted monomer which can be identified or detected by means well known to those skilled in the art.

[0096] The invention also relates to optical, electro-optical or nano-electrical components and systems, in particular multi-layer systems, or to display waveguides, security or brand protection elements, barcodes, optical gratings, filters, retardation films such as 3D retardation films, correction films, reflective polarizing films, absorptive polarizing films, anisotropic scattering films, correction and retardation films, twisted retardation films, cholesteric liquid crystal films, guest-host liquid crystal films, monomeric corrugated films, smectic liquid crystal films, polarizers, piezoelectric cells, thin films exhibiting nonlinear optical properties, decorative optical elements, brightness enhancement films, components for wavelength band selection correction, components for multi-domain correction, multi-bio the use of the alignment layer of the present invention in the manufacture of components of optical liquid crystal displays, achromatic retarders, polarization state correcting / adjusting films, components of optical or electro-optical sensors, components of brightness enhancing films, components for optical communication devices, G / H polarizers with anisotropic absorbers, reflective circular polarizers, reflective linear polarizers, MC (monomer corrugated films), liquid crystal displays, in particular twisted nematic (TN) liquid crystal displays, hybrid aligned nematic (HAN) liquid crystal displays, electrically controlled birefringence (ECB) liquid crystal displays, super twisted nematic (STN) liquid crystal displays, optically compensated birefringence (OCB) liquid crystal displays, pi-cell liquid crystal displays, in-plane switching (IPS) liquid crystal displays, fringe field switching (FFS) liquid crystal displays, vertically aligned (VA) liquid crystal displays; all the above display types are applied either in transmission or reflection or transflective mode.

[0097] Optical, electro-optical or nano-electrical components and systems, especially multi-layer systems and devices, can be patterned or unpatterned.

[0098] The term patterning preferably means birefringence patterning and / or layer thickness patterning and / or optical axis orientation patterning and / or polymerization degree patterning. Birefringence means the difference between the refractive index of extraordinary light and ordinary light.

[0099] The present invention therefore further relates to optical, electrooptical or nanoelectrical elements, systems and devices comprising a composition comprising a compound of formula (I) obtainable by the inventive method of the present invention or a composition comprising a homopolymer comprising a repeating structural unit of formula (I) and at least one monomer of formula (I).

[0100] Preferred are optical, electro-optical or nano-electrical elements, systems and devices comprising an alignment layer according to the invention and at least one orientable layer, such as a liquid crystal layer or a liquid crystal polymer layer.

[0101] An optical component, system or device produces, manipulates, or measures electromagnetic radiation.

[0102] Electro-optical components, systems or devices operate by modifying the optical properties of a material with an electric field, and thus involve the interplay between the electromagnetic (optical) and electrical (electronic) states of the material.

[0103] The alignment layer has the ability to align slave materials, for example liquid crystals, such as nematic liquid crystals, with their long axes along a preferred direction.

[0104] The invention also relates to the use of the alignment layer of the invention to orient a slave material. By "slave material" we mean any material capable of establishing anisotropy upon contact with a photoaligned material. The nature of the anisotropy of the photoaligned material and the anisotropy of the slave material may differ from each other. An example of a slave material is a liquid crystal. Such a slave material is applied on top of the alignment layer. The slave material may be applied by coating and / or printing, with or without a solvent, and may be applied to the entire alignment layer or only a part of it. The slave material may be polymerized by heat treatment or exposure to actinic radiation. The polymerization may be carried out under an inert atmosphere, such as nitrogen, or under vacuum. The slave material may further contain isotropic or anisotropic dyes and / or fluorescent dyes.

[0105] The slave material may comprise polymerizable and / or non-polymerizable compounds. In the context of the present invention, the terms "polymerizable" and "polymerized" are intended to encompass the meanings of "crosslinkable" and "crosslinked", respectively. Similarly, "polymerization" is intended to encompass the meaning of "crosslinking".

[0106] Liquid crystal polymer (LCP) material as used in the context of this application is intended to mean a liquid crystal material comprising liquid crystal monomers and / or liquid crystal oligomers and / or liquid crystal polymers and / or crosslinked liquid crystals. When the liquid crystal material comprises liquid crystal monomers, such monomers may be polymerized, typically after contact with the photoalignable polymeric material of a composition comprising the photoalignable polymeric material of the present invention, resulting in anisotropy in the LCP material. Polymerization may be initiated by heat treatment or by exposure to actinic radiation, preferably including UV light. The LCP material may consist of a single type of liquid crystal compound, but may also be a composition of different polymerizable and / or non-polymerizable compounds, where not all compounds need to be liquid crystal compounds. Furthermore, the LCP material may contain additives, such as photoinitiators, or isotropic or anisotropic fluorescent and / or non-fluorescent dyes.

[0107] The terms "anisotropy" or "anisotropic" refer to a property that is directionally dependent. Something that is anisotropic may look different or have different properties in different directions. These terms refer, for example, to optical absorption, birefringence, electrical conductivity, molecular orientation, properties for the orientation of other materials (e.g., liquid crystals), or mechanical properties such as elastic modulus. In the context of this application, the term "orientation direction" refers to the axis of symmetry of the anisotropy.

[0108] The use for inducing planar, tilt or vertical alignment of an adjacent liquid crystal layer is preferred; more preferred is the use for inducing planar or vertical alignment in an adjacent liquid crystal layer.

[0109] Surprisingly, it has been found in the present invention that the method for the synthesis of aryl acrylic acid ester photoalignable polymeric materials comprising repeating structural units of formula (I), comprising steps a-d, represents an economic improvement over the methods disclosed in the prior art. Moreover, said method also has improved yields. Moreover, the polymerization does not require the use of toxic radical initiators, and the polymerization process is easily controllable and reliable. The homopolymers obtained are of high purity. The compositions comprising the compound of formula (I) obtained by the method of the present invention, or the compositions comprising the homopolymers comprising repeating structural units of formula (I) and at least one monomer of formula (I), can be easily controlled in terms of the ratio of the homopolymer and monomer amounts by methods known to those skilled in the art. These methods include, but are not limited to, gel permeation chromatography (GPC). The compositions have the advantage that they can be used directly as photoalignment compositions and do not require further isolation and / or purification steps.

[0110] Moreover, it has been surprisingly found in the present invention that as the amount of monomer compound in the photoalignment composition is increased, a variety of tilt angles are available, independent of the exposure energy.

[0111] Furthermore, it has been surprisingly found in the present invention that as the amount of monomer compound in the photoalignment composition increases, the resulting alignment layer and alignment layer coated with liquid crystal polymer become more robust to deviations and variations in exposure energy. [Brief description of the drawings]

[0112] The invention is further illustrated by the accompanying drawings, in which it is emphasized that the various features are not necessarily drawn to scale. [Figure 1.1]FIG. 1 illustrates examples of the properties of liquid crystal alignment at two interfaces (liquid crystal polymer layer-air interface and liquid crystal-alignment layer interface) for various exposure energies of the alignment layer (where the tilt angle corresponds to the angle between the main axis of the liquid crystal molecules and the substrate surface). The solid line represents the tilt angle at the interface between the liquid crystal and alignment layer. The dotted line represents the tilt angle at the interface between the liquid crystal polymer layer and air. The different symbols correspond to various ratios of polymer 1 and its monomer compound 2.

[0113] The polymers of the present invention are further illustrated by the following examples. EXAMPLES

[0114] [Example 1] Preparation of 4-[8-(2-methylprop-2-enoyloxy)octoxy]benzoic acid [2-methoxy-4-[(E)-3-methoxy-3-oxo-prop-1-enyl]phenyl] compound 2

[0115] [ka] 10.0 g of 4-((8-hydroxyoctyl)oxy)benzoic acid (from Angene), 1.20 g of hydroquinone, 1.30 g of p-toluenesulfonic acid monohydrate, and 30.0 g of methacrylic acid are suspended in 100.0 g of toluene. The resulting mixture is heated to reflux under nitrogen while removing the water formed via a Dean-Stark separator. After 4 hours of reflux, 2 / 3 of the toluene is distilled off under vacuum. 100 mL of ethanol is added to the reaction mixture, which is then cooled to room temperature. 100 g of water is slowly added to form a "white precipitate". The solid is filtered off and washed three times with water to give 6.35 g of compound 1 as a white solid with an HPLC purity of >93%. This compound 1 is 4-[8-(2-methylprop-2-enoyloxy)octoxy]benzoic acid. Compound 1 DMSO-d 6Medium 1H NMR (300MHz): 12.59 (s, 1H), 7.87 (d, 2H), 6.98 (d, 2H), 6.01 (s, 1H), 5.65 (s, 1H), 4.08 (m, 4H), 1.86 (s, 3H), 1.71 (m, 4H), 1.32 (m, 8H). 4.5 g of compound 1 and 0.03 g of butylated hydroxytoluene (BHT) are dissolved in 100 g of toluene. The reaction mixture is heated to 70° C. and 1.22 mL of thionyl chloride is added dropwise to the reaction mixture. After the addition, the mixture is stirred at 70° C. for 4 hours. Excess thionyl chloride is distilled off from the reaction mixture under vacuum. The reaction mixture is cooled to 10° C. and a solution of 2.8 g of methyl (E)-3-(4-hydroxy-3-methoxy-phenyl)prop-2-enoate, 0.16 g of dimethylaminopyridine (DMAP) and 2.2 mL of trimethylamine in 40 g of toluene is added dropwise to produce a white cloudy solution. The reaction mixture is stirred at room temperature for 30 minutes. 100 g of methanol is added to the reaction mixture at 10° C. to produce a white precipitate, which is filtered off and washed with methanol and water to give 3.1 g of compound 2 as a white solid with HPLC purity >95%. Compound 2 DMSO-d 6 Medium 1H NMR (300MHz): 8.05 (d, 2H), 7.68 (d, 1H), 7.57 (s, 1H), 7,37 (d, 1H), 7.25 (d, 1H), 7.11 (d, 2H), 6.98 (d, 1H), 6.01 (s, 1H), 5.66 (s, 1H), 4.09 (m, 4H), 3.81 (m, 6H), 1.88 (s, 3H), 1.72 (m, 4H), 1.34 (m, 8H).

[0116] [Example 2] Polymerization Methods Preparation of poly 4-[8-(2-methylprop-2-enoyloxy)octoxy]benzoate [2-methoxy-4-[(E)-3-methoxy-3-oxo-prop-1-enyl]phenyl] (Polymer 1). 14 g of compound 2 is mixed with 52.50 g of cyclohexanone (CHN) and stirred under nitrogen until completely dissolved. The reaction mixture is heated to 75° C. under nitrogen. 0.22 g of Luperox® LP (dilauryl peroxide from Sigma) is added in one portion. The reaction mixture is maintained at 75° C. for 5 hours, and then the temperature is increased to 100° C. After 1 hour at 100° C., the reaction mixture is cooled to room temperature and filtered to obtain the polymer in CHN solution. The resulting polymer solution is called photoalignment composition 1.

[0117] [ka] Photoalignment composition 1 contains polymer 1 (Mw=264690 and Mn=60031) and its monomer compound 2 in a ratio of 90:10 (measured by GPC).

[0118] [Example 3] The crosslinkable liquid crystal compound 1 (LCC1) is pentyl 2,5-bis[[4-(6-prop-2-enoyloxyhexoxy)benzoyl]oxy]benzoate and has the following molecular structure.

[0119] [ka] The crosslinkable liquid crystal compound 2 (LCC2) is 3-cyanopropyl 2,5-bis[[4-(6-prop-2-enoyloxyhexoxy)benzoyl]oxy]benzoate and has the following molecular structure:

[0120] [ka] The crosslinkable monomer compound 3 is 4-(6-prop-2-enoyloxyhexoxy)benzoic acid (4-cyanophenyl) and has the following molecular structure:

[0121] [ka] The solution S-LCP1 was 35 wt.% 98.525% LCC1 1.00% Irgacure 907 (BASF) 0.20% Tinuvin 123 (BASF) 0.25% Tegoflow 300 (Evonik) 0.025% BHT (Sigma Aldrich) is prepared by dissolving the components in a 65% by weight solvent mixture of 80% n-butyl acetate and 20% CNH and stirring the mixture at room temperature for 30 minutes. The solution S-LCP2 was 25 wt.% 48.45% LCC2 48.45% Compound 3 3.0% Irgacure 369 (IGM Resins) 0.1% BHT (Sigma Aldrich) is prepared by dissolving the components in a 75% by weight solvent mixture of 80% methyl ethyl ketone (MEK) and 20% cyclohexanone (CHN) and stirring the mixture at room temperature for 30 minutes. The solution S-LCP3 was 35 wt.% 49.45% LCC1 49.45% LCC2 1.0% Irgacure 907 (BASF) 0.1% BHT (Sigma Aldrich) is prepared by dissolving the components in a 65% by weight solvent mixture of 60% butyl acetate (BA) and 40% cyclohexanone (CHN) and stirring the mixture at room temperature for 30 minutes.

[0122] [Example 4]: Preparation of photoalignment solution (PAS1) Solution PAS1 is prepared by adding 15% by weight of Photoalignment Composition 1 to 85% by weight of cyclopentanone (CP) and stirring the mixture at room temperature for 30 minutes.

[0123] Application examples Example 1: Preparation of primer-coated substrate Triacetate cellulose (TAC) foil was coated with a primer solution (20 wt% solids DYMAX OC-4021 in 80% butyl acetate) using a Kbar coater (bar size 1). The wet film was dried at 80°C for 30 seconds; the resulting dry film had a thickness of approximately 2 μm. The dry film was then exposed to UV light (1500 mJ under nitrogen atmosphere).

[0124] [Example 2]: Preparation of alignment layer using PAS1 The primer-coated TAC substrate of Example 1 was Kbar coated with PAS1 (bar size 0). The wet film was dried at 80°C for 30 seconds; the dry film had a thickness of approximately 100 nm. The dry film was then coated with 10-100 mJ / cm 2 The films were exposed to alignment light, which was collimated linearly polarized UV (LPUV) light (280-320 nm) with various exposure energies of 1000 nm to 1500 nm. The polarization plane was at 0° with respect to the reference edge on the TAC substrate.

[0125] [Example 3]: Preparation of one LCP layer oriented by an alignment layer The LCP1 layer is prepared on top of the alignment layer of Example 2 by Kbar coating (bar size 1) solution S-LCP1. The wet layer is dried at 50° C. for 60 seconds and the liquid crystal is then applied at 30 mW / cm 2 2 The film is crosslinked by exposure to UV-A for 50 seconds at room temperature under a nitrogen atmosphere.

[0126] [Example 4]: Evaluation of orientation For an efficient manufacturing process, it is of interest to know how much exposure energy the photoalignment layer requires to achieve good visible uniform (no visible defects) contrast in the LCP layer oriented by the alignment layer. The fabricated films were analyzed between crossed polarizers. The quality of the orientation is ranked as follows: · ▲▲ Very good alignment Uniform orientation · ▲ Good orientation (disclination line (DL) area < 1% of coating area) ○ Small DL (1<<5% of coating area) × DL visible (>5% of coating area) ×× Uneven or no orientation The optical device was fabricated in the following sequence: a primer-coated substrate (as fabricated in Application Example 1) was coated with an alignment layer using PAS1 (as described in Application Example 2) and an LCP layer (as shown in Application Example 3) was aligned. Different exposure energies were used to align the photoalignment material. A summary of the results is shown in the table below:

[0127] [Table 1] PAS1 requires very low LPUV doses to obtain very good alignment quality without visible defects.

[0128] [Example 5]: Preparation of alignment layer using PAS1 The COP substrate was pretreated with Corona (0.75 kW, 20 rpm, 2 times). The pretreated substrate was Kbar coated with PAS1 (bar size 0). The wet film was dried at 80 °C for 30 s. The thickness of the dry film was about 100 nm. The dry film was then heated to 120 mJ / cm 2 The film was exposed to unpolarized UV light (broadband Fusion H bulb type) with an exposure energy of 1000 .mu.m.

[0129] [Example 6]: Preparation of two LCP layers oriented by an alignment layer The LCP2 layer is prepared on top of the alignment layer of Example 5 by Kbar coating (bar size 2) solution S-LCP2. The wet layer is dried at 50° C. for 120 seconds and the liquid crystal is then coated under nitrogen atmosphere at room temperature with 30 mW / cm 2 2The liquid crystal composition was crosslinked by exposure to UV-A for 50 seconds to form a hardened layer of the liquid crystal composition. The liquid crystal was homeotropically aligned. The properties of the retardation layer are shown in Figure 1. The dotted lines represent the change in retardation of the COP substrate at different viewing angles. The solid lines represent the retardation measurements of the LCP2 layer of Example 6 at different viewing angles. The liquid crystal layer behaves as a positive C-plate. Homeotropic alignment is induced by the photoalignment solution PAS1 aligned without polarized light.

[0130] [Example 7]: Preparation of photoalignment solution PAS2 The photoalignment solution PAS2 is prepared by adding 3 wt% mixtures of polymer 1 and its monomer compound 2 in ratios of 97:3, 90:10, 85:15, 80:20 and 50:50 to 97 wt% cyclopentanone or to a mixture of 50% cyclopentanone (CP) and 50% cyclohexanone (CHN) and stirring the mixture at room temperature for 30 min.

[0131] [Example 8]: Preparation of alignment layer using PAS2 D263 glass (borosilicate glass) substrates were cleaned and spin-coated with various PAS2 containing various ratios of polymer 1 and its monomer compound 2 at 1,700 rpm for 30 seconds. The wet films were dried at 180°C for 10 minutes. The thickness of the dry films was about 100 nm. The dry films were spin-coated at 10, 20, 30, 40, 50, 60, 70, 80 and 90 mJ / cm. 2 The sample was exposed to polarized UV light (high pressure mercury lamp) with an exposure energy of 1000 Å at an oblique incidence angle of 50° from the normal to the surface. The plane of polarization was at 0° with respect to a reference edge on a D263 glass substrate.

[0132] [Example 9]: Preparation of LCP3 layer oriented by alignment layer PAS2 The LCP3 layer is prepared on top of the alignment layer of Example 8 by spin-coating solution S-LCP3 at 2,500 rpm for 40 seconds. The wet layer is dried at 60.5° C. for 60 seconds, and the liquid crystal is then coated at room temperature under a nitrogen atmosphere at 30 mW / cm 2 . 2The film was crosslinked by UV-A exposure for 50 seconds to form a hardened layer of the liquid crystal composition. The liquid crystal showed hybrid alignment, where the tilt angle of the liquid crystal at the PAS2-LCP3 interface was generally different from that at the LCP3-air interface. For most of the film, the tilt angle appears to vary linearly between the interfacial tilt angles. The characteristics of liquid crystal alignment at the interface for various exposure energies of PAS2 are shown in Figure 1, where the tilt angle corresponds to the angle between the principal axis of the liquid crystal molecule and the substrate surface. The solid line represents the tilt angle at the PAS2-LCP3 interface. The dotted line represents the tilt angle at the LCP3-air interface. The different symbols correspond to different ratios of polymer 1 and its monomeric compound 2.

Claims

1. A method for producing a photo-alignable polymer material, comprising the steps of: The photo-alignable polymer material is - Formula (I): 【Chemistry 17】 and a homopolymer comprising a monomer represented by at least one monomer of formula (I) A composition comprising [In the formula, M １ means a repeating monomer unit from the group consisting of acrylates and methacrylates; S １ is a spacer unit, and when m and n are 0, the spacer unit is S ２ and when at least one of m or n is 1, the spacer unit is S ３ and where S ２ and S ３ is a substituted or unsubstituted straight or branched chain -(CH ２ ) ｒ -, and even - (CH ２ ) ｒ -O-, -(CH ２ ) ｒ -O-(CH ２ ) ｓ -, -(CH ２ ) ｒ -O-(CH ２ ) ｓ -O-, -(CH ２ ) ｒ -CO-, -(CH ２ ) ｒ -CO-O-, -(CH ２ ) ｒ -O-CO-, -(CH ２ ) ｒ -NR ２ -, -(CH ２ ) ｒ -CO-NR ２ -, -(CH ２ ) ｒ -NR ２ -CO-, -(CH ２ ) ｒ -NR ２ -CO-O- or -(CH ２ ) ｒ -NR ２ -CO-NR ３ - and optionally C １ -C ２４ - alkyl, hydroxy, fluorine, chlorine, cyano, ether, ester, amino, amido mono- or polysubstituted; and ２ The - group may be replaced by a linking group, an alicyclic or aromatic group; and where r and s are each integers from 1 to 20, except that S ２ For S, 3≦r+s≦24; and ３ 8≦r+s≦24 for R ２ and R ３ each independently represents hydrogen or lower alkyl; Ring A represents unsubstituted phenylene or phenylene substituted with alkyl or alkoxy; Ring B represents unsubstituted phenylene or phenylene substituted with fluorine, alkyl or alkoxy; Ring C is unsubstituted or optionally substituted phenylene with fluorine, chlorine, cyano, alkyl or alkoxy, or pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thiophenylene, 2,5-furanylene, 1,4- or 2,6-naphthylene; Y 1 is a single covalent bond, —CO—O—, or —O—OC—; Y 2 is —CO—O—; where m and n each represent an integer from 0 to 4; Z means -O-; and D is hydrogen or is optionally halogenated at least once or contains one or more siloxane moieties; １ -C ３ is a straight alkyl chain; The following steps a to d: a. Formula (II): 【Chemistry 18】 [In the formula, Ring C is unsubstituted or optionally substituted phenylene with fluorine, chlorine, cyano, alkyl or alkoxy, or pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thiophenylene, 2,5-furanylene, 1,4- or 2,6-naphthylene; and Y is CH, q=1 and R=COOR″; where R″ is hydrogen or a C 1 -C 3 linear alkyl chain, optionally halogenated at least once or containing at least one siloxane moiety, Formula (III): 【Chemistry 19】 [In the formula, M １ means a repeating monomer unit from the group consisting of acrylates and methacrylates; S １ is as defined above; Ring A is unsubstituted phenylene or phenylene substituted with alkyl or alkoxy; Ring B is unsubstituted phenylene or phenylene substituted with fluorine, alkyl or alkoxy; Y 1 is a single covalent bond, -CO-O- or -O-OC-; Y 2 in formula (III) is —CO—O— or —CO—; m and n each represent an integer of 0 to 4; b. Optionally, reacting the compound obtained in step a with a compound of formula (V): 【Chemistry 20】 wherein X is OH, F, Cl or I; Z and Z′ are each independently either H or halogen; q and q′ are each independently an integer from 0 to 2; p is an integer from 0 to 10; and r and r' are each independently an integer from 0 to 3; c. polymerizing the compound obtained under step a or b with organic or inorganic peroxides; d. Stopping the reaction by heating The method includes:

2. The method of claim 1 , provided that no further purification steps are performed on the produced photoalignable polymeric material.

3. In each of formulas (I) and (III), S １ is a spacer unit, where m and n are 0, the spacer unit is S ２ and when at least one of m or n is 1, the spacer unit is S ３ where S ２ is C ４ -C20 alkylene; and ３ is C ８ -C20 alkylene; and alkylene is unsubstituted or substituted, straight or branched chain alkylene containing one or more -CH ２ 3. The method according to claim 1, wherein the - group is optionally replaced by at least one linking group, an alicyclic or / and an aromatic group.

4. In each of formulas (I) and (III), n=0 and m=1, and S ３ is -(CH ２ ) ｒ - (wherein r is 8, 9, 10, 11, or 12), as well as -(CH ２ ) ｒ -O-, -(CH ２ ) ｒ -CO-O- and -(CH ２ ) ｒ The method according to claim 3, wherein the alkyl group is -O-CO-.

5. In each of formulas (I) to (III), n=0 and m=1, and M １ means a repeating monomer unit from the group consisting of acrylates and methacrylates; Ring B is unsubstituted phenylene or phenylene substituted with fluorine, alkyl or alkoxy; Y in formula (I) ２ is —CO—O—; Y 2 in formula (III) is —CO—C— or —CO—; S ３ is a substituted or unsubstituted straight or branched chain -(CH ２ ) ｒ -, and even - (CH ２ ) ｒ -O-, -(CH ２ ) ｒ -O-(CH ２ ) ｓ -, -(CH ２ ) ｒ -O-(CH ２ ) ｓ -O-, -(CH ２ ) ｒ -CO-, -(CH ２ ) ｒ -CO-O-, -(CH ２ ) ｒ -O-CO-, -(CH ２ ) ｒ -NR ２ -, -(CH ２ ) ｒ -CO-NR ２ -, -(CH ２ ) ｒ -NR ２ -CO-, -(CH ２ ) ｒ -NR ２ -CO-O- or -(CH ２ ) ｒ -NR ２ -CO-NR ３ -wherein the suffix "r" is an integer between 8 and 20; and Ring C is unsubstituted phenylene or phenylene substituted with alkyl or alkoxy; Z means -O-; and D is optionally halogenated at least once or contains one or more siloxane moieties; １ -C ３ 3. The method according to claim 1 or 2, wherein the alkyl chain is linear or branched.

6. The method according to claim 5, wherein in each of formulas (I) and (III), the suffix "r" of S 3 is an integer between 8 and 12.

7. The method of claim 5, wherein in each of formulas (I) and (III), the suffix "r" of S 3 is 8, 9, 10, 11 or 12.

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