Title:
METHOD FOR MANUFACTURING OPTICAL FILM
Document Type and Number:
WIPO Patent Application WO/2017/169306
Kind Code:
A1
Abstract:
The present invention addresses the problem of providing a method for manufacturing an optical film that has a soluble polyimide as the main component, is easily reused as a return scrap, and has a reduced phase difference nonuniformity resulting from phase difference developability and bowing phenomena during stretching. This method for manufacturing an optical film containing a soluble, transparent polyimide resin is characterized by including a step for casting dope on a support body and forming a cast film, a step for detaching the cast film from the support body, and a step for stretching the detached cast film. The method is further characterized in that the stretching temperature during the stretching step is within the range of (Tg-250°C) to (Tg-100°C), wherein Tg (°C) is the glass transition temperature of the polyimide resin. The method is further characterized in that the change in the temperature of the film from the start to the end of stretching does not exceed 70°C, and the stretching temperature is at least 50ºC higher than the boiling point Tb (ºC) of the main solvent.
Inventors:
IWAGAMI NAOYA (JP)
MIYAMOTO HIROSHI (JP)
MIYAMOTO HIROSHI (JP)
Application Number:
PCT/JP2017/006409
Publication Date:
October 05, 2017
Filing Date:
February 21, 2017
Export Citation:
Assignee:
KONICA MINOLTA INC (JP)
International Classes:
G02B5/30; B29C41/24; B29C55/02; C08G73/10; C08J5/18; G02B1/04; G09F9/30; H01L51/50; H05B33/02; B29K79/00; B29L7/00; B29L11/00
Domestic Patent References:
| WO2011125563A1 | 2011-10-13 | |||
| WO2006112286A1 | 2006-10-26 |
Foreign References:
| JP2006117903A | 2006-05-11 | |||
| JP2000169579A | 2000-06-20 | |||
| JP2012077144A | 2012-04-19 |
Attorney, Agent or Firm:
KOYO INTERNATIONAL PATENT FIRM (JP)
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