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:
May. 11, 2021
Filed:
Dec. 27, 2016
Sumitomo Chemical Company, Limited, Tokyo, JP;
Nobuyuki Hatanaka, Osaka, JP;
Shinnosuke Yoshioka, Osaka, JP;
Shoichi Ozawa, Niihama, JP;
Tatsuaki Kasai, Osaka, JP;
SUMITOMO CHEMICAL COMPANY, LIMITED, Tokyo, JP;
Abstract
Disclosed is a retardation film which shows a high light selective absorbency to visible rays having short wavelengths near 400 nm to have a high light resistance, and which can give, when used in a display device, good display properties to the display device. This film is a retardation film, satisfying all of the following formulae (1) to (4): 2≤A(380) (1), 0.5≤A(400) (2), 0.4≥A(420)/A(400) (3), and 100 nm≤Re(550)≤170 nm (4), in which each A(λ) represents the absorbance of the film at a wavelength λ nm, and Re (550) represents the in-plane retardation value of the film to a light ray having a wavelength of 550 nm.