▎ 摘　　要

NOVELTY - Manufacture (p1) of carbon nanoparticles involves heating an organic solvent in the presence of a catalyst, preferably strong acid or strong base. USE - Manufacture of carbon nanoparticles e.g. graphene quantum dots and carbon quantum dots used in antibacterial agent and antiviral agent for forming composite nanoparticles and composite film (all claimed). Can also be used as fluorescent probes for bioimaging and medical material. ADVANTAGE - The method enables easy manufacture of carbon nanoparticles having large average particle diameter, in short time. The agent containing the carbon nanoparticles has desired antibacterial activity against Escherichia coli, Salmonella and Staphylococcus aureus. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) the carbon nanoparticles, which comprise a graphite structure, and are soluble in organic solvents, and have an average particle size of 5-1000 nm; (2) composite nanoparticles, which comprise the carbon nanoparticles and a polymer; and (3) composite film, which comprises the carbon nanoparticles and a polymer.