Abstract: An ink transfer printing device in which ink transfer is driven by a viscosity change in ink. The ink transfer printing device includes an ink reservoir for retaining ink held under pressure. The ink reservoir is associated with an ink transfer surface which has a plurality of perforations. Under ambient conditions, the viscosity of the ink prevents flow of the ink through the perforations. The ink transfer printing device also includes a viscosity control unit for inducing a change in the viscosity of the ink near certain perforations thereby enabling a controlled amount of the ink near each of these certain perforations to flow through these certain perforations to an outer surface of the ink transfer surface. The ink which has flowed onto the outer surface can then be transferred to an intermediate surface or a printing media. A method for viscosity-driven ink transfer printing is also disclosed.

Abstract: A color ink transfer printing device in which ink transfer is driven by a viscosity change in ink. The color ink transfer printing device includes a viscosity control unit and first through fourth ink containers for retaining colored ink held under pressure. Each of the ink containers retains a different color ink. The first through fourth ink containers are respectively associated with first through fourth perforated ink transfer surfaces. Under ambient conditions, the viscosity of the colored ink prevents flow of the colored ink through the perforations. The viscosity control unit induces a change in the viscosity of the colored ink near certain perforations, thereby enabling a controlled amount of the colored ink near each of the certain perforations to flow through these certain perforations and onto the ink transfer surface corresponding thereto. The colored ink which has flowed onto the ink transfer surface can then be transferred to an intermediate surface or a printing media.

Abstract: An ink transfer printing device having improved ink dot size control. The ink transfer printing device includes an ink container for retaining ink and a perforated ink transfer surface coupled to the ink container. The ink transfer surface includes at least one concentric region on the ink transfer surface about each of the perforations to control the spread of the ink. The concentric regions form flow barriers which impede the spread of the ink at each orifice. The ink dot size control provided by the present invention facilitates continuous toning, gray scale toning and multi-color printing.