Cellulose ester film, its manufacturing method, optical retardation film, optical compensation sheet, elliptic polarizing plate, and image display

摘要

A manufacturing method of a cellulose ester film satisfying the relationships, Nx>Ny>Nz, and 0.8<=R_t/R₀<=3.5, the method comprising casting a cellulose ester dope containing a solvent of a good solvent and a poor solvent on a support to form a web; peeling the web from the support; transporting the peeled web (step D0); holding the edges in the transverse direction of the web (step A); stretching the resulting web in the transverse direction while applying a tension; reducing the tension in the transverse direction of the web; and drying the stretched web, wherein the residual solvent content of the web is 5 to 90% by weight at the beginning in the step A, and the residual poor solvent content in the residual solvent content of the web is from 15 to 95% by weight at the terminal point in the Step D0.