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:
Feb. 20, 2018
Filed:
Jun. 21, 2006
Masanori Yoshihara, Tokyo, JP;
Tetsuya Toyoshima, Tokyo, JP;
Kohei Arakawa, Tokyo, JP;
Zeon Corporation, Tokyo, JP;
Abstract
A protective film for polarizing plate made by laminating k layers (k being an integer of 2 to 7) of thermoplastic resin, in which a refractive index n(λ) at a wavelength X in the range of 380 to 780 nm of the i th thermoplastic resin layer as well as a refractive index n(λ) at a wavelength λin the range of 380 to 780 nm of the i+1 th thermoplastic resin layer have a relationship of In |n(λ)−n(λ)|≦0.045 (i being an integer of 1 to k−l); and a polarizing plate comprising the protective film and a polarizer. The protective film has an in-plane retardation Re at a wavelength λof 550 nm of 50 nm or less, and is obtained by coextruding at least one layer (A) of thermoplastic resin having of a negative photoelastic coefficient with at least one layer (B) of thermoplastic resin having a positive photoelastic coefficient.