Abstract: A novel photoactive copolymer and its use as orientation layers for liquid crystals and in the construction of unstructured and structured optical elements and multilayer systems. The copolymer contains side chains incorporating photoreactive groups and simultaneously side chains of general formula (I) wherein the total number of rings, including the number of rings in optionally present condensed systems is at least two and at most six; wherein the broken line symbolizes the point of linkage to the polymer main chain; and wherein the variables are defined in the disclosure.

Abstract: A mesogenic, crosslinkable mixture comprising at least one polymerisable liquid crystal and at least one polymerisable dichroic dye of the general formula I: wherein A represents a dichroic residue exhibiting at least partial absorption in the visible region >400 nm; n1, n2, n3, n4 signifies 0 or 1 whereby the sum of n1, n2, n3 and n4 is >0, and B1 and B4 represent a group of substructure II wherein the broken line symbolises the linkage to said dichroic residue.

Abstract: A photoactive side-chain polymer from the class of polyimides, polyamide acids and esters thereof, comprising as a side-chain a dendritic block incorporating photoactive groups at its surface. The dendritic block preferably represents a unit of formulae Ia, Ib or a combination of them, for example formulae Ic, wherein the broken line symbolizes the linkage to the polyimide main chain. The polymer may be used as an orientation layer for liquid crystals and in the construction of unstructured and structured optical elements and multi-layer systems.

Abstract: A photoactive polymer from the class of polyimides, polyamide acids and esters thereof comprises as a side-chain a photocrosslinkable group of the general formula (I) wherein the broken line indicates the point of linkage to the polyimide main chain and wherein: B is a straight-chain or branched alkyl residue which is optionally substituted, wherein one or more non-adjacent CH2 groups may independently be replaced by a group Q; D represents an oxygen atom or —NR1— wherein R1 represents a hydrogen atom or lower alkyl; and S3 represents a spacer unit. The polymers may be used as orientation layers for liquid crystals and in the construction of unstructured and structured optical elements and multi-layer systems.

Abstract: A photoactive side-chain polymer from the class of polyimides, polyamide acids and esters thereof, comprising as a side-chain a dentritic block incorporating photoactive groups at its surface. The dentritic block preferably represents a unit of formulae Ia, Ib or a combination of them, for example formulae Ic wherein the broken line symbolizes the linkage to polyimide main chain. The polymer may be used as orientation layer for liquid crystals and in the construction of unstructured and structured optical elements and multi-layer systems.

Abstract: A mesogenic, crosslinkable mixture comprising at least one polymerisable liquid crystal and at least one polymerisable dichroic dye of the general formula (I) wherein A represents a dichroic residue exhibiting at least partial absorption in the visible region >400 nm: n1, n2, n3, n4 signifies 0 or 1 whereby the sum of n1, n2, n3, n4 is >0, and B1 to B4 represent a group of substructure II wherein the broken line symbolizes the linkage to said dichroic residue.

Abstract: The invention relates to a novel photoactive copolymer and its use as orientation layers for liquid crystals and in the construction of unstructured and structured optical elements and multi-layer systems.

Abstract: In one embodiment, the invention relates to compounds of the formula (I) wherein G1 and G2 independently represent a polymerisable mesogenic residue, X and Sp are as defined herein and M represents an achiral group of formula (II) as defined herein. The compounds of the invention may, for example, be useful as curable liquid crystals and for preparing liquid crystal films.

Abstract: In one embodiment, the invention relates to compounds of the formula (I) wherein G1 and G2 independently represent a polymerizable mesogenic residue, and X, Sp, and Q are as defined herein. The compounds of the invention may, for example, be useful as curable liquid crystals and for preparing liquid crystal films.

Abstract: The present invention relates to polymers of the general formula I: in which M1, M1′, M2 denote a recurring monomer unit from the group: acrylate, methacrylate, 2-chloroacrylate, 2-phenylacrylate; w, w1, w2 are molar fractions of the comonomers with 0<w≦1, 0≦w1<1 and 0≦w2≦0.

Abstract: Optically active butane-1,2,3,4-tetraol derivatives of formula (I). The compounds may be used as doping agents for liquid crystals for a wide range of applications, such as solid state cholesteric filters for projection displays, circular polarizers, and optical filters.

Abstract: Photocrosslinkable, mesogenic mixtures, especially for optical or electro-optical devices, exhibit improved properties when, in addition to containing two or more liquid-crystalline monomers each having at least two terminal polymerizable groups, they contain at least one non-liquid-crystalline monomer having no or, at most, one alicyclic or aromatic structural unit and having at least one terminal polymerizable group.

Abstract: A photoactive polymer from the class of polyimides, polyamide acids and esters thereof comprises as a side-chain a photocrosslinkable group of the general formula (I) 1

Abstract: The present invention relates to polymers of the general formula I: 1

Abstract: The invention relates to novel crosslinkable, photoactive polymers from the class of polyimides, polyamide acids and esters thereof, and to their use as orientation layers for liquid crystals and in the construction of unstructured and structured optical elements and multi-layer systems. The polymers contain as side-chains photo-crosslinkable groups of the following formula: The broken line indicates the point of linkage to the polymer main chain. In addition, A, B each independently of the other represents unsubstituted or optionally fluoro-, chloro-, cyano-, alkyl-, alkoxy-, fluoroalkyl- or fluoroalkoxy-substituted phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, cyclohexane-1,4-diyl, piperidine-1,4-diyl, piperazine-1,4-diyl; C represents unsubstituted or optionally fluoro-, chloro-, cyano-, alkyl-, alkoxy-, fluoroalkyl- or fluoroalkoxy-substituted phenylene, or pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thiophenylene, 2,5-furanylene, 1,4- or 2,6-naphthylene.

Abstract: The invention relates to novel crosslinkable, photoactive silane derivatives of the formula I mixtures of silane derivatives of the formula I and mixtures of silane derivatives of the formula I with uncrosslinkable silane derivatives as usually used for silanizing inorganic, oxide-containing surfaces. The invention furthermore relates to the use of silane derivatives of the formula I and of mixtures which contain at least one silane derivative of the formula I as orientation layers for liquid crystals and for the production of unstructured or structured optical elements and multilayer systems.

Abstract: A compound of formula in which R1 and R2 each independently represent and alkyl or alkenyl group in which one or more hydrogen atoms is optionaly substituted by fluorine, chlorine, or cyano; and in which optionally one or more non-adjacent methylene groups are optionaly replaced by —O—, —COO— or —OOC—; Z1 to Z4 each independently represent a single bond, —CH2CH2—, —CH2O—, —OCH2—, —C≡C—, —(CH2)4—, —(CH2)3O—, —CH═CH—CH2O—, OCH2—, —CH═CH—, —CH═CH—(CH2)2— or —(CH2)2—CH═CH—, with the proviso firstly that the oxygen atom is not linked directly with the chiral dioxane ring and secondly Z2 and Z3 may also represent —COO— or —OOC—; R* and S* signify that the denoted carbon have the (R) or (S) configuration respectively or the optical antipode thereof; and one of A, B and

Abstract: An optical frequency conversion element has a wave-guiding layer which consists of a .chi..sup.(2) -active ferroelectric liquid crystal. The monomeric or polymeric liquid crystal material has a periodic structure which permits the so-called quasi phase matching of a guided laser beam. The period length of the structure is equal to twice the coherence length l.sub.c =.pi./.DELTA..beta. of the material, whereby .DELTA..beta.=.beta..sub.o (2.omega.)-2.beta..sub.o (.omega.), with .omega.=angular frequency of the fundamental wave, 0=zero-order mode and .beta.=propagation constant of the mode.

Abstract: Polymerisable optically active compounds have the general formula: ##STR1## where: W.sup.1 denotes a polymerisable residue,S.sup.1 denotes a spacer unit,Y.sup.1 denotes a single bond, or one of the groups --O--, --COO--, --OOC--, --OCOO--, --S--, --CONH-- or --NHCO--,M denotes a divalent mesogenic group, andR.sup.1 and R.sup.2 denote straight chain, branched or cyclic alkyl groups with up to 8 carbon atom.

Abstract: The invention provides novel cross-linkable, photoactive silane derivatives and mixtures with 3-aryl-acrylic acid esters and amides. The present invention also provides orienting layers for liquid crystals, and non-structured and structured optical elements and multi-layer systems based on the silane mixtures and derivatives.