abstract |
A methacrylic resin composition having high heat resistance, excellent birefringence, and excellent heat stability and molding processability is provided. A methacrylic resin composition comprises: a methacrylic resin including a structural unit (X) having a cyclic structure-containing main chain, the structural unit (X) being at least one type selected from the group consisting of an N-substituted maleimide monomer-derived structural unit, a glutarimide-based structural unit, and a lactone ring structural unit; and an organic phosphorous compound, wherein a glass transition temperature is more than 120° C. and 160° C. or less, a content of a phosphorus element is 10 mass ppm to 1000 mass ppm, and a ratio P3/P5 of an integral value P3 of a spectral peak assigned to trivalent phosphorus to an integral value P5 of a spectral peak assigned to pentavalent phosphorus in 31 P-NMR measurement is 0.2 to 5.0. |