Patent ID: 6668723
Filing Date: 2003-12-30
Classification: B41F,B41P

Abstract:
A method for regulating the ink-to-wetting agent equilibrium in a rotary offset printing machine, comprising the steps of:presetting a wetting agent quantity supplied to a printing form; calibrating the wetting agent quantity supplied at a certain ink quantity; adjusting the wetting agent quantity to a wetting agent quantity setpoint value that is characteristic for a specific print job; increasing or decreasing the ink quantity from an ink quantity setpoint value to an ink quantity target value desirable for the specific printing job; increasing or decreasing the wetting agent quantity setpoint value in a same direction as the increasing or decreasing of the ink quantity to a wetting agent quantity target value; and regulating the wetting agent quantity supplied in a closed control loop as a function of the wetting agent quantity target value; wherein the wetting agent quantity supplied for the calibrating step is reduced until a signal of a light reflectance sensor traverses a minimum level.