Invention Grant
- Patent Title: Polarized resin film and process for producing same
-
Application No.: US14655988Application Date: 2013-12-27
-
Publication No.: US09865996B2Publication Date: 2018-01-09
- Inventor: Tetsuhiro Kodani , Eri Mukai , Takashi Kanemura , Meiten Kou , Susumu Kawato , Satoshi Shimizu
- Applicant: DAIKIN INDUSTRIES, LTD. , TOHO KASEI CO., LTD.
- Applicant Address: JP Osaka JP Nara
- Assignee: DAIKIN INDUSTRIES, LTD.,TOHO KASEI CO., LTD.
- Current Assignee: DAIKIN INDUSTRIES, LTD.,TOHO KASEI CO., LTD.
- Current Assignee Address: JP Osaka JP Nara
- Agency: Wenderoth, Lind & Ponack, L.L.P.
- Priority: JP2012-288103 20121228; JP2013-185470 20130906
- International Application: PCT/JP2013/085216 WO 20131227
- International Announcement: WO2014/104345 WO 20140703
- Main IPC: G01N21/00
- IPC: G01N21/00 ; H01T19/04 ; G01N21/84 ; C08J7/12 ; G01N21/896

Abstract:
An object of the present invention is to provide a polarized vinylidene fluoride/tetrafluoroethylene copolymer resin film that can significantly reduce, when used as an optical film, the deterioration of the quality of video or still images formed by display elements.The present invention provides a polarized vinylidene fluoride/tetrafluoroethylene copolymer resin film having 2,000 or fewer spot defects per m2, the number of spot defects being measured by a defect measurement method;the method using an surface inspection system in which a CCD camera is placed so as to detect defects at an angle of 45 degrees relative to an LED source, defects of the film are read within a rectangular range of 300 mm in a width direction (the direction perpendicular to the scanning direction), and 150 mm in a machine direction (the scanning direction), while the film is scanned under the camera at a rate of 20 m/min;wherein first, defects having a bright area of 1.5 mm2 or less and a dark area of 1.4 mm2 or less are selected; andnext, in order to remove defects resulting from causes other than a corona treatment contained in these defects, a circumscribed rectangle of defect is set so as to have two sides along the scanning direction, and the number of only defects that have a circumscribed width of 2.88 mm or less, a circumscribed length of 2.3 mm or less, an aspect ratio of −39 to +27, an occupancy area ratio in the circumscribing rectangle of 4,000 to 6,950, and an area ratio of −3,100 to +5,200, is automatically counted as spot defects by the surface inspection system.
Public/Granted literature
- US20150349500A1 POLARIZED RESIN FILM AND PROCESS FOR PRODUCING SAME Public/Granted day:2015-12-03
Information query