MANUFACTURE OF PHASE DIFFERENCE FILM

• Main Authors: HOSOI MASAHIRO, NAGOSHI TAMIAKI
• Format: Patent
• Language: English
• Published: 26.01.1999
• Edition: 6
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CHEMISTRY; COMPOSITIONS BASED THEREON; GENERAL PROCESSES OF COMPOUNDING; INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULARARTICLES; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; METALLURGY; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PHYSICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL; WORKING-UP

PROBLEM TO BE SOLVED: To manufacture a phase difference film adapted to an optical application of satisfactory quality with particularly extremely small speckle of retardation value by eliminating phase difference speckle of an infinitesimal range. SOLUTION: The method for manufacturing a phase difference film made of polymer by casting polymer solution on a support, drying the resultant film and then orienting it comprises the steps of releasing the film containing 8 to 20 wt.% of solvent from the support, then grasping the film by a pin tenter so that a length of the film of a direction perpendicular to an orientation axis becomes 99 to 105%, drying it until the containing solvent amount of the film becomes 2.0 wt.% or less, and further uniaxially orienting the film 1.1 to 3.2 times in a feeding direction of the film.