Patent ID: 6732645
Filing Date: 2004-05-11
Classification: B41F,B41P

Abstract:
A method of presetting ink in a printing apparatus, said apparatus comprisingan ink supply mechanism capable of variably supplying ink, and an ink transfer mechanism capable of receiving said ink from said ink supply mechanism and transferring said ink onto a plate cylinder provided to print an ink image on a printing sheet being fed in a predetermined feeding direction, said method comprising the steps of: a) setting a first target density for a plurality of ink key regions defined on each printing sheet along said feeding direction; b) performing a first printing operation under a first feedback control of said ink supply mechanism using said first target density; c) performing a second printing operation under a second feedback control of said ink supply mechanism using a second target density lower than said first target density after a required number of sheets are printed in said step b); and d) when a printed sheet has a density lowered to said second target density, judging that the amount of ink remaining on said ink transfer mechanism is equal to an amount required to restart said printing apparatus for a next printing operation, thereby to stop said second printing operation.