Films of copolymers of methyl methacrylate and O-acryloyl acetophenone oxime (AAPO), which is a monomer bearing photobase generating groups, were UV-irradiated and dyed in the presence of p-benzoquinone or 1,4-naphthoquinone. Acyloxyimino groups in AAPO units were transformed into pendant amino groups on irradiation, and films became well dyeable with an acid dye. The quinones in the films caused crosslinking, which reduced the damage of the films during the dyeing processes compared to those without quinones. Sublimed p-benzoquinone was also introduced into heated films after irradiation, which resulted in the success of lowering the surface roughness of the films during the dyeing processes.