Patent attributes
The image formation apparatus satisfies a user's demand to effectively use a sheet by writing an image to the marginal sheet edge, and prevents that toner is not transferred to the sheet but adhered to a transfer roller when the sheet is slightly misregistered from its accurate position, whereby back stain occurs in a next sheet. In this apparatus, an area in which the image is masked is changed by a CPU, according to an input mode of a image signal from an image signal generation unit. In a printer mode that the image signal is input from a host computer, image masking signals by which an image can be formed up to the sheet edge are given to gate circuits so as to expand the image up to the marginal sheet edge. In a mode that the image signal is input from an image reader, the image masking signals by which a margin can be provided at the sheet edge are given to the gate circuits so as to limit an image area.
