METHOD FOR PRODUCING RETARDATION FILM

• Main Authors: SEIKE KUNIHIRO, YAMAMOTO SHOGO, MURAKAMI NAHO, MAEDA TAKESHI, HAIDA NOBUYUKI, MIYATAKE MINORU, EHARA KEIGO
• Format: Patent
• Language: English
• Published: 09.02.2012
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; 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; INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULARARTICLES; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; PERFORMING OPERATIONS; PHYSICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PROBLEM TO BE SOLVED: To provide a method for continuously producing an optical anisotropic element excellent in contrast and viewing angle characteristics and having less color irregularity and contrast irregularity.SOLUTION: The method for producing a retardation film is characterized in that: the temperature of a fused resin w2 at a die exit 16 is controlled to be in a range from a temperature higher by 70°C than the glass transition temperature of the fused resin w2 to a temperature higher by 100°C than the glass transition temperature of the fused resin w2; and the temperature of at least one of a first roll 21 and a second roll 31 is controlled to be in a range from a temperature lower by 35°C than the glass transition temperature of the fused resin w2 to a temperature higher by 10°C than the glass transition temperature of the fused resin w2.