PURPOSE: To obtain a substrate material which is lighter than a glass, hardly breakage, having advantages in photoelastic module, thermal expansion, hardness, density, transparency, water absorption and double refraction as compared to a plastic and having high resistance against a polar solvent by using a specific polymer to capable of setting the production process temp. of a display to ≥180°C.

CONSTITUTION: As the substrate material for the liquid crystal display, the polymer of the polycyclic olefin or its mixture is incorporated. The polymer is produced by polymerizing at least one of the monomers expressed in formula I and formula II without opening the ring. In the formulas, each of R1-R4 is same identical or different and is a hydrogen atom or a 108C alkyl radical, and the same radical in the various formulas can have different meanings. Further, a cyclo-olefin expressed by formula III can be incorporated in the substrate. In the formula, (n) is an integer of 2-10.