Patent ID: 8132887
Filing Date: 2012-03-13
Classification: B41F,B41P

Abstract:
1. A process for measuring and controlling a color value of one or more colored image portions which are printed on a planar substrate, the process comprising: (a) providing one or more colored image portions which are printed on a planar substrate, each colored image portion comprising one or more colors produced by one or more colored inks; (b) providing one or more pairs of reference markers printed on the planar substrate in one or more ink zones and positioned adjacent to said one or more colored image portions, wherein each pair of reference markers comprises a primary reference marker and a secondary reference marker; wherein the primary reference marker comprises black ink and the secondary reference marker comprises one or more of cyan, magenta and yellow ink components; wherein each of said primary reference marker and said secondary reference marker has an ink density value, wherein said black, cyan, magenta and yellow inks each have an individual ink density value when present; (c) providing at least one imaging assembly, wherein the imaging assembly is capable of capturing digital representations of each of said reference markers; (d) controlling the positioning and linear movement of said imaging assembly across the planar substrate; (e) selecting and acquiring a digital image with the imaging assembly of the primary reference marker and the secondary reference marker within one or more pairs of reference markers in at least one ink zone; (f) analyzing the digital image of the primary reference marker and the secondary reference marker of each imaged reference marker pair to determine the ink density value for each reference marker within each imaged reference marker pair and the individual ink density values for each ink component of each reference marker; (g) comparing the ink density value of the primary reference marker and the ink density value of the secondary reference marker of each imaged reference marker pair and determining any difference between the ink density value of said primary reference marker and the ink density value of said secondary reference marker of said imaged reference marker pair, and optionally storing said difference in a memory; (h) optionally comparing the ink density value of the primary reference marker and/or the ink density value of the secondary reference marker of each imaged reference marker pair with a target ink density value for at least a portion of the one or more colored image portions on the substrate in at least one ink zone, and determining any difference between the ink density value of the primary reference marker and/or the ink density value of the secondary reference marker of each imaged reference marker pair and the target ink density value for the at least a portion of the one or more colored image portions on the substrate in at least one ink zone, and optionally storing said difference in a memory; (i) optionally adjusting the ink quantity of black and/or colored ink being printed onto the substrate such that the ink density value of the primary reference marker in a reference marker pair is equivalent to the ink density value of the secondary reference marker in said reference marker pair, and/or such that the ink density value of the primary reference marker and/or the ink density value of the secondary reference marker in a reference marker pair is equivalent to the ink density value of a manually specified ink density value, and/or such that the ink density value of the primary reference marker and/or the ink density value of the secondary reference marker in a reference marker pair is equivalent to the target ink density value for at least a portion of the one or more colored image portions on the substrate in at least one ink zone; and (j) optionally repeating steps (d)-(i) for at least one of any additional ink zones.