TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The content of monomer (I), and (meth)acrylic acid and/or its salt contained in the monomer mixture is 1-99.9 wt.% and 0.1-30 wt.%, respectively. The monomer mixture further contains 0-98.9 wt.% monomer (a) copolymerizable with monomer (I) and (meth)acrylic acid and/or its salt, and 0-2 pts. wt. polyfunctional monomer, with respect to 100 pts. wt. total content of monomer (I), (meth)acrylic acid and/or its salt, and monomer (a). The monomer (I) is chosen from benzyl (meth)acrylate, dicyclopentanyl (meth)acrylate and phenoxyethyl (meth)acrylate.    TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The polymer of monomer mixture is a hard polymer. The graft copolymer has a crosslinked structure formed from (meth)acrylic-type crosslinked polymer. The crosslinked structure is formed by polymerizing 50-100 wt.% acrylic ester, 0-50 wt.% copolymerizable monomer (a), and 0.05-10 pts. wt. polyfunctional monomer, with respect to 100 pts. wt. total content of acrylic ester and copolymerizable monomer (a). The content of crosslinked structure contained with respect to 100 pts. wt. resin material is 1-60 pts. wt. Thermoplastic resin (A) is acrylic resin having hydroxyl group and/or carboxyl group, glutarimide acrylic resin, lactone ring-containing acrylic polymer, or partially hydrogenated styrene-type polymer. The partially hydrogenated styrene-type polymer is obtained by carrying out partial hydrogenation of aromatic ring of styrene-type polymer obtained by polymerizing styrene monomer and copolymerizable monomer. The acrylic resin has a cyclic-anhydride repeating unit, and contains N-substituted maleimide compound as copolymerization component. The resin material further contains inorganic fine particles having birefringence and low-molecular-weight compound having birefringence. The graft ratio of multilayer structure-containing graft copolymer is 10-250 wt.%. The content of crosslinked polymer layer contained with respect to 100 wt.% multilayer structure-containing graft copolymer is 10-90 wt.%. The multilayer structure-containing graft copolymer preferably has layer (B1) in an inner layer, and layer (B2) in an outer layer. Preferred Component: Glutarimide acrylic resin has a piperidine-2,6-dione-containing unit of formula (II) and carboxyl group-containing unit of formula (III), and does not contain aryl group-containing unit of formula: -(CH2-CH(-R7)(-R8))-.R1,R2=H or 1-8C alkyl;R3=H, 1-18C alkyl, 3-12C cycloalkyl, or 5-15C aryl;R4,R5,R7=H or 1-8C alkyl;R6=1-18C alkyl, 3-12C cycloalkyl or 5-15C aryl;andR8=6-10C aryl.Preferred Properties: The volume average particle diameter of the crosslinked structure is 20-450 nm. Acrylic resin has a glass transition temperature of 100 degrees C or more and an acid value of 0.01-5 mmol/g. The resin material has 1 wt.% loss temperature of 290 degrees C or more, tensile fracture point elongation of 10% or more, orientation birefringence of -1.7x 10-4-1.7x 10-4 and photoelastic constant -4x 10-12 Pa-1-4x 10-12 Pa-1. The photoelastic constant of thermoplastic resin (A) and photoelastic constant of polymer (B) are opposite signs. The thickness of the film is 10-500 mu m.