To provide a method for stretching a continuous film which can easily prepare, using a continuous thermoplastic resin film web having an even thickness, a continuous stretched film having an optical axis different from the longitudinal direction of the film, and to provide a phase difference film provided by the stretching method and an elliptically polarizing plate having the phase difference film stacked thereon.
This method for stretching a continuous thermoplastic resin film includes the steps of: providing a continuous thermoplastic resin film being travelled in the longitudinal direction of the film; holding both ends of the continuous thermoplastic resin film, with a plurality of pairs of holding tools, in a direction at a desired angle of less than 90 degrees to the longitudinal direction of the film; and, in this state, stretching the film in a mutually separating direction. The film is travelled in such a manner that, in a stretching section, the direction connecting the plurality of pairs of holding tools always makes the above desired angle and the moving speeds of the holding tools are identical to each other.
NAKADA SHOICHI
ISHIMARU TSUNATOSHI
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