PHOTOALIGNMENT POLYMER, ALIGNMENT LAYER AND LIQUID CRYSTAL RETARDATION FILM COMPRISING THE SAME

• Main Authors: LEE, SUNG KYOUNG, YOO, DONG WOO, CHUN, SUNG HO, CHOI, DAI SEUNG, HAN, JEONG YOON
• Format: Patent
• Language: English; Korean
• Published: 17.03.2014
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; 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 PROCESSES OF COMPOUNDING; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; ORGANIC MACROMOLECULAR COMPOUNDS; PHYSICS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; THEIR PREPARATION OR CHEMICAL WORKING-UP; WORKING-UP

The present invention relates to a photoalignment polymer which can be desirably applied to an alignment layer or the like of a stereoscopic display device because an alignment direction according to a polarization direction can be easily changed. The present invention also relates to an alignment layer and a liquid crystal retardation film comprising the photoalignment polymer. The photoalignment polymer comprises a cyclic olefin-based repeating unit substituted with one or more photoreactive functional groups. The photoalignment polymer has an absorption rate (AR) of 0.02 or higher defined by a specific formula when primary photoalignment is performed by radiating first polarized UV light having a wavelength of 280 to 315nm and a first polarization direction in the total quantity of light of 60 mJ/cm2 or less, and secondary photoalignment is performed by radiating second polarized UV light having a wavelength of 280 to 315nm and a second polarization direction which is changed by 90° from the first polarization direction in the total quantity of light of 60 mJ/cm2 or less. [Reference numerals] (AA) Liquid crystal; (BB) Alignment layer; (CC) Substrate