| abstract |
(57) [Summary] [Problem] To provide a production method for mass-producing a low-cost birefringent film whose optical axis is inclined with respect to the film surface, and to obtain the obtained birefringent film. [Structure] The main chain is composed of a hydrocarbon, acrylate, methacrylate, siloxane, or the like, and has a side chain containing a structure in which a substituent such as biphenyl, terphenyl, phenylbenzoate, or azobenzene is bonded to a photosensitive group such as a cinnamic acid group. Irradiating a linearly polarized ultraviolet ray to a photosensitive side-chain type polymer film containing a certain proportion of a side chain having no photosensitive group bonded thereto to advance a dimerization reaction of the photosensitive group, and To obtain a birefringent film whose optical axis is inclined in the direction of. |