| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a long retardation film having a slow axis in an oblique direction while precisely controlling a direction of the slow axis and direction variations and obtaining high production efficiency.SOLUTION: A step of stretching a film comprises: gripping a film at right and left ends with right and left pitch-variable clips 20 with variable longitudinal clip pitches, respectively; preheating the film; obliquely stretching the film; and disengaging the clips 20. The oblique stretching comprises, while enlarging a distance between the right and left clips, controlling a change rate in the clip pitch along a travelling direction of the clips at one of the right and left ends to be different from a change rate in the clip pitch along the travelling direction of the clips in the other end, and/or controlling a position where the clip pitch in the travelling direction of the clips at one end starts to change to be different from a position where the clip pitch in the traveling direction of the clips in the other end starts to change. A moving speed of the clips 20 is decreased just before the gripping step and/or in a period from the gripping step to the oblique stretching step. |
