Patent ID: 6485134
Filing Date: 2002-11-26
Classification: B41J

Abstract:
Process for modification of the position at which electrically-charged ink droplets arrive on a substrate (27), in an adjustable and sequential manner, the droplets originating from a print head (25) after being charged by charge electrodes (20) connected to a voltage generator (32), the paths of the droplets being affected by deviation electrodes (23, 24) deviating the droplets depending on their electrical charge between N positions defined by their row j, a first position X1, a last position XN, and Nâˆ’2 intermediate positions, the N positions defining a frame obtained by a burst of droplets in the form of a straight segment approximately perpendicular to a direction of relative movement between the head (25) and the substrate (27), process characterized in that an additional random algebraic voltage is superposed on a nominal voltage to be applied to the charge means on each droplet to be directed to the substrate (27), a maximum amplitude of the additional random algebraic voltage being a fraction less than 1 of the difference between the nominal voltage to be applied to the charge electrodes (20) for the said droplet and the nominal voltage to be applied to the charge electrodes (20) for one of the two immediately adjacent droplets in the frame.