| abstract |
The present invention relates to a retardation film and a method for producing the same, wherein the retardation film is formed of a resin containing a polymer having crystallinity, the NZ coefficient is less than 1, and the production method includes the following steps: a laminating step, which is in the first film A step of laminating a second film on one or both sides to obtain a third film, wherein the first film is formed of a resin containing a crystalline polymer, having a glass transition temperature of Tg (° C.) and a melting point of Tm (° C.), the above-mentioned The shrinkage rate of the second film in at least one direction at (Tg+30)°C is 5 to 50%; in the shrinkage step, the third film is heated to Tg°C to (Tg+30)°C so as to follow at least one direction. A fourth film is obtained by shrinking the area in the direction of shrinkage by 5 to 50%; and a secondary heating step of heating the fourth film to (Tg+50)°C to (Tm-40)°C. |