| abstract |
An optically isotropic acrylic resin film having excellent transparency, heat resistance, toughness, optical isotropy, and durability against changes in the external environment such as high temperature and high humidity is provided. (I) An optically isotropic acrylic containing a thermoplastic copolymer containing a lactone ring-containing monomer unit and satisfying the following (a), (b) and (c): Resin film. (A) The glass transition temperature is 120 ° C. or higher. (B) Tensile breaking elongation is 10% or more. (C) The absolute value of the in-plane retardation (Re) is 10 nm or less, and the absolute value of the thickness retardation (Rth) is 10 nm or less. [Selection figure] None |