The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 24, 2018
Filed:
Mar. 12, 2014
Nitto Denko Corporation, Ibaraki-shi, Osaka, JP;
Takashi Shimizu, Ibaraki, JP;
Satoshi Hirata, Ibaraki, JP;
Seiji Kondo, Ibaraki, JP;
Nao Murakami, Ibaraki, JP;
NITTO DENKO CORPORATION, Ibaraki-shi, JP;
Abstract
Provided is a method capable of producing a retardation film suppressed in biaxiality, having a small Nz coefficient, and having a slow axis in an oblique direction with high production efficiency. The production method for a retardation film of the present invention includes: holding left and right side edge portions of a film to be stretched with left and right variable pitch-type clips configured to have clip pitches changing in a longitudinal direction, respectively; preheating the film; reducing, under a state in which a position at which the clip pitch of the clips on one side out of the left and right clips starts to reduce and a position at which the clip pitch of the clips on another side starts to reduce are set to different positions in the longitudinal direction, the clip pitch of each of the clips to a predetermined pitch to subject the film to oblique stretching; and releasing the clips holding the film.