| 摘要 |
PURPOSE:To prevent the rear soiling of a transfer material, to increase efficiency in an image forming process, moreover, to improve the quality of an image formed on a transfer material, and to increase image forming efficiency, when a multi-image is formed by plural photosensitive drums. CONSTITUTION:The photosensitive drums 1a, 1b, 1c, and 1d are rotated and a toner image for measuring a density (subsequently, it is called 'a reference toner image'), on the image forming regions of these photosensitive drums 1a,..., and 1d. The density of the reference toner image is measured by density measuring sensors 23a, 23b, 23c, and 23d, and a control means 24 adjusts the density based on the result of the measurement. The reference toner image whose density is completed to measure is transferred on a carrying belt 8, but a region where the reference toner image is transferred, is a region (nonimage region) where a transfer material is not placed, so that the rear of the transfer material is not soiled. The transfer material is placed with the nonimage region avoided, to continue image formation without stopping. |
