| 摘要 |
Provided is a producing method for a retardation film with a reverse wavelength dispersion property, which is highly reliable in terms of a small wavelength dispersion change and is low in display unevenness due to a position dependence of a retardation variation. The production method is designed for a retardation film which satisfies the following formulas (1) and (2): 0.7<Re1[450]/Re1[550]<0.97  (1); and 1.5×10−3<&Dgr;n<6.0×10−3  (2) (where: Re1[450] and Re1[550] represent, respectively, in-plane retardation values thereof as measured by using light of a wavelengths of 450 nm and light of a wavelength of 550 nm, at 23° C.; and &Dgr;n represents an in-plane birefringence thereof as measured by using light of a wavelength of 550 nm). This method comprises: a step of continuously conveying and supplying a long polymer film; a stretching step of stretching the polymer film in a direction transverse to a conveyance direction; a first shrinkage step of, after the stretching step, causing the polymer film to shrink in the transverse direction; and a second shrinkage step of, after the first shrinkage step, causing the polymer film to shrink in the transverse direction, wherein a shrinkage temperature T1 (° C.) in the first shrinkage step and a shrinkage temperature T2 (° C.) in the second shrinkage step satisfy the following formula (3): 1<(T1−T2)≦̸10  (3). |
