A process cartridge includes a protective agent, a photoconductor, a charging unit, a development unit, a cleaning unit, and an application unit. The protective agent includes paraffin as main component. The photoconductor has a surface including polycarbonate applied with the protective agent. The development unit develops a latent image on the photoconductor. The cleaning unit removes materials remaining on the photoconductor. The application unit applies the protective agent to the surface of photoconductor. One peak in a given binding energy range is used to determine a coating condition of the photoconductor coated by the agent. The coating condition is determined by comparing an area ratio A.sub.0 before applying the agent and an area ratio A after applying the agent, each of which is an area ratio with respect to a total area of C1s spectrum of the photoconductor. The coating ratio of the photoconductor is computed by (A.sub.0-A)/A.sub.0.times.100.