Synthesis of new conjugated dyes carrying dialkylamino and ketone groups through multi-step routes. Visible light photoinitiating properties of these dyes using as one-component photoinitiators studied by photo-DSC. Efficient visible light photoinitiating polymerization of methyl methacrylate by one-component photoinitiators. Greater visible light photoinitiating efficiencies of one-component photoinitiators than two-component ones.