Image forming apparatus and image forming system capable of forming an image with an invisible image forming material

An image forming system, comprising:

• a multi-functional peripheral and a server, wherein
• the multi-functional peripheral comprises:
• a first interface configured to communicate with a server;
• a printer which comprises a first image forming device configured to form an image with a visible image forming material, and a second image forming device configured to form an image with an invisible image forming material;
• a scanner which comprises a first image reader configured to read an image formed with the visible image forming material, and a second reader configured to read an image formed with the invisible image forming material;
• an operation panel which comprises a display configured to display an information, and operation button;
• and
• a system controller which comprises an image memory configured to store a print image that should be printed on a medium, a first interface configured to communicate with the server, and a processor configured to send an issue request of authentication information to the server via the first interface, acquire the authentication information which the server issued according to the issue request and carry out an image forming processing on the print image with the visible image forming material by the first image forming device and the authentication information with the invisible image forming material by the second image forming device, and
• the server comprises:
• a second interface configured to communicate with the multi-functional peripheral;
• and
• a processor configured to issue the authentication information in a case of receiving the issue request of the authentication information from the multi-functional peripheral through the second interface and send the issued authentication information to the multi-functional peripheral through the second interface.