It is an object of the present invention to provide an ink jet printing apparatus which sufficiently heats a head even in a low-temperature environment, which enables a proper image to be printed by stably ejecting ink, and which can be inexpensively and simply constructed. The method includes a new wash step which increases the tissue repair properties of the TRCs of the invention. The configured component utilizes the cryptographic key obtained from the certification authority in cryptographic communication with the prospective component, and determines whether the prospective component is the authentic component based on whether the cryptographic key is successfully utilized in the cryptographic communication. The NMS receives the Aggregate Change Identifiers of MIB groups in response to polling, from a SNMP agent. Each monitor and control end unit has a dynamically assigned address. In the decreased pressure mode, the pressing roller applies a decreased pressure incapable of fixing the toner image on the sheet to the fixing roller.