Production method of cellulose film, cellulose film, protective film for polarizing plate, optical functional film, polarizing plate, and liquid crystal display

Abstract

A production method of cellulose film wherein cellulose film is produced by preparing a polymer solution through dissolving cellulose ester in a solvent containing a prescribed organic solvent as the main component, forming a filmy object from the prepared polymer solution, and evaporating the solvent in the filmy object; the residual amount of the organic solvent is reduced while the film quality is not degraded, and the production efficiency is degraded to a least possible extent; a poor solvent, highest in boiling point among the materials contained in the solvent, is added in the content ranging from 0.1 wt % to 1.0 wt %, taking the total amount of the solvent in the prepared polymer solution to be 100 wt %; and the solubility of cellulose ester in the poor solvent is inferior to the solubility of the cellulose ester in the organic solvent which is the main component of the solvent.

Dependencies are inferred from the claim text.