POLARIZER AND ITS MANUFACTURING METHOD, POLARIZING PLATE, OPTICAL FILM AND IMAGE DISPLAY DEVICE

• Main Authors: MIZUSHIMA HIROAKI, SHIMIZU KENJI, AOKI TAKESHI, KAMEYAMA TADAYUKI, SUGINO YOICHIRO, WADA MORIMASA
• Format: Patent
• Language: English
• Published: 02.12.2004
• Edition: 7
• 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 manufacturing a polarizer excellent in neutral hue properties when the plarizers are superposed one upon another so that the MD directions of them cross each other at a right angle. SOLUTION: In this method for manufacturing the polarizer by applying at least a swelling process (1), a dyeing process (2), a crosslinking process (3) and a stretching process (4) in an MD direction to a polyvinyl alcohol film in this order, a stretching process (5) for stretching the polyvinyl alcohol film so that the draw ratio in the TD direction of the film is 1-1.3 times is provided after the dyeing process (2) but before the stretching process (4) in the MD direction and the stretching in the MD direction of the film is not performed until the crosslinking process (3) but the stretching treatment in the MD direction of the film is performed so that the draw ratio in the MD direction is 4-4.5 times in the stretching process (4) in the MD direction. COPYRIGHT: (C)2005,JPO&NCIPI