Method for producing long retardation film

Patent metadata

Field	Value
Publication number	US-9482802-B2
Application number	US-201414454291-A
Country	US
Kind code	B2
Filing date	Aug 7, 2014
Priority date	Aug 9, 2013
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

A method for producing a long retardation film having an optical axis in an oblique direction relative to the length direction of the long retardation film is provided.

First claim

What is claimed is:

1. A long retardation film comprising a long substrate, a long optical alignment membrane, and a long retardation membrane in this order, wherein
a direction of an alignment restricting force of the long optical alignment membrane is oblique relative to a length direction of the long substrate,
a thickness of the long retardation membrane is 3 μm or less, and
a direction of an optical axis of the long retardation membrane is oblique relative to the length direction of the long substrate, and wherein the long retardation film has a wavelength dispersion property satisfying the following formulas (1), (2), and (3):
Re (450)/ Re (550)≦1.00  (1)

1.00≦ Re (650)/ Re (550)  (2)

100< Re (550)<160  (3)

wherein, in the formulas, Re(λ) represents an in-plane retardation value relative to a light having a wavelength of λ nm.

2. A long circularly polarizing plate in which a long polarizing film is stacked in the side of the long retardation membrane of the long retardation film according to claim 1 .

Assignees

• Sumitomo Chemical Co

Inventors

• Sase Mitsutaka
• Hatanaka Nobuyuki
• Kobayashi Tadahiro

Classifications

• B32B2305/72

  Cured, e.g. vulcanised, cross-linked · CPC title

• B32B38/164

  Drying · CPC title

• G02B1/12

  by surface treatment, e.g. by irradiation · CPC title

• B32B2398/00

  Unspecified macromolecular compounds · CPC title

• G02B5/32

  Holograms used as optical elements · CPC title