Title:
METHOD FOR PRODUCING PHASE DIFFERENCE FILM, AND METHOD FOR PRODUCING CIRCULARLY POLARIZING PLATE
Document Type and Number:
WIPO Patent Application WO/2024/004601
Kind Code:
A1
Abstract:
Provided is a method for producing a phase difference film satisfying specific optical properties, the production method comprising: a first step for preparing a first film that has a resin layer (P1) formed from a thermoplastic resin P having a positive intrinsic birefringence value; a second step for stretching the first film at least one time to produce a second film having a resin layer (P2) that is a layer obtained as the result of the stretching of the resin layer (P1); a third step for laminating a resin layer (N1) formed from a thermoplastic resin N having a negative intrinsic birefringence value on the second film to produce a third film; and a fourth step for stretching the third film at least one time to produce the phase difference film having both of a resin layer (P) that is a layer obtained as the result of the stretching of the resin layer (P2) and has a retardation axis (P) and a resin layer (N) that is a layer obtained as the result of the stretching of the resin layer (N1) and has a retardation axis (N) forming an angle of 90°±5° with the retardation axis (P).
Inventors:
OSATO KAZUHIRO (JP)
Application Number:
PCT/JP2023/021666
Publication Date:
January 04, 2024
Filing Date:
June 12, 2023
Export Citation:
Assignee:
ZEON CORP (JP)
International Classes:
G02B5/30; B29D7/01; B29D11/00
Domestic Patent References:
| WO2009031433A1 | 2009-03-12 | |||
| WO2019208512A1 | 2019-10-31 | |||
| WO2019208508A1 | 2019-10-31 | |||
| WO2018079746A1 | 2018-05-03 | |||
| WO2018079745A1 | 2018-05-03 |
Foreign References:
| JP2010204347A | 2010-09-16 | |||
| JP2007199616A | 2007-08-09 | |||
| JP2009169086A | 2009-07-30 | |||
| JP2003161832A | 2003-06-06 |
Attorney, Agent or Firm:
SAKAI INTERNATIONAL PATENT OFFICE (JP)
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