1. An image transfer device for transferring images of a marking substance to sheets of a recording medium which comprises: an endless image transfer member provided for receiving consecutive images of a marking substance on its surface, the image transfer member being urged, in an operative state of the transfer device, into moving contact with a counter member to form a transfer zone therebetween for transferring the respective consecutive images to respective sheets of a recording medium fed consecutively through the transfer zone; an endless cleaning member having, in an operative state of the image transfer device, a surface in moving contact with the surface of the image transfer member in a cleaning zone downstream of the transfer zone, the surface of the cleaning member carrying a layer of tacky substance; and a controllable applicator unit for providing, in an operative state of the image transfer device, predetermined patterns of a cleaning substance to the surface of the image transfer member in at least some non-image areas, the non-image areas being the areas between consecutive images coinciding with the areas between consecutive sheets, the predetermined patterns of cleaning substance on the image transfer member being substantially completely transferred to the surface of the cleaning member in the cleaning zone.