PHOTOALIGNMENT OF LIQUID CRYSTALS USING POLY(VINYLSTILBAZOLIUM)POLYMERS

• Main Authors: TEEGARDEN, DAVID MORRISON, SHUKLA, DEEPAK, WELTER, THOMAS ROBERT
• Format: Patent
• Language: English; French
• Published: 05.07.2007
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; FREQUENCY-CHANGING; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; ORGANIC MACROMOLECULAR COMPOUNDS; PHYSICS; TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; THEIR PREPARATION OR CHEMICAL WORKING-UP

The present invention relates to a photoalignable material comprising a photoactive stilbazolium-containing polymer of formula (I) wherein, Ma, Mb, Mc are monomer units making up the polymer; x, y, z, are mole fractions of the monomer units Ma, Mb, Mc, wherein in each case 0<x=l; 0=y<L, 0=Z<L ; Sa and Sb are spacer units; Za is a stilbazolium unit which can undergo photochemical isomerization/dimerization reactions; Zb is a stilbazole unit, and n varies from 4 to 10,000. The present invention also relates to a display using a layer of the photoaligned material and methods for aligning the orientation layer as well as orienting a liquid crystal layer applied to the photoaligned orientation layer. La présente invention se rapporte à un matériau photo-alignable qui comprend un polymère contenant du stilbazolium de formule (I) dans laquelle M35, Mb, M0 sont des motifs monomères formant le polymère ; x, y, z, sont des fractions molaires des motifs monomères Ma, Mb, Mc, et dans chaque cas 0<x<l, 0<y<l, 0<z<l ; S3 et Sb sont des motifs d'espacement, Z3 est un motif de stilbazolium qui peut subir des réactions photochimiques d'isomérisation/dimérisation ; Zb est un motif de stilbazolium, et n varie de 4 à 10 000. La présente invention se rapporte aussi à un affichage utilisant une couche du matériau photo-alignable, ainsi qu'à des procédés d'alignement de la couche d'orientation et à des procédés d'orientation de la couche de cristaux liquides s'appliquant à la couche d'orientation photo-alignée.