| 摘要 |
PROBLEM TO BE SOLVED: To enhance whole throughput or the durability of a color printer even when a black and white color mixed document is printed and to reduce printing cost. SOLUTION: A color printer receives printing data from a PC client to start a printing job, stores the printing data in a memory device and forms image data on the basis of the printing data. A black and white printing mode is set as a printing mode by the start of the printing job and, when color printing data is contained in the printing data of a certain page (printing page) in the memory device the black and white printing mode is changed over to a color printing mode and the image data formed on the basis of the printing data is sent to an engine to perform printing in the color printing mode, and printing due to the color printing mode is repeated on and after. That is, the changeover from the color printing mode to the black and white printing mode is prohibited during the performance of one printing job. |
