Patent ID: 8279378

Claim:
A producing method for a lengthwise optical laminate comprising the following steps 1 to 3: step 1: a step of coating and drying a coating solution comprising a birefringent material and a solvent on a surface of a lengthwise base material to form a birefringent film such that a birefringence index (Δn xz [590]) in the thickness direction at a wavelength of 590 nm is 0.02 or more, and produce a lengthwise sheet (A) comprising the base material and the birefringent film; step 2: a step of stretching a lengthwise film of a hydrophilic polymer containing a dichroic material so that a stretched rate is from 3 times to 5 times based on the original length and a shrinking rate is 55% or less to produce a lengthwise polarizer (B); and step 3: a step of laminating the lengthwise sheet (A) obtained in the step 1 on one plane of the lengthwise polarizer (B) obtained in the step 2 to produce the lengthwise optical laminate, wherein the birefringence index (Δn xz [590]) is a value calculated from the expression: (Δn xz [590])=nx−nz, the nx signifies a refractive index in the direction of the birefringent film in which in plane refractive index is maximum (slow axis direction) and the nz signifies a refractive index in the thickness direction of the birefringent film.