US 12,411,413 B2
System and method for mitigating trailing edge voids in flexo printing
Jörg Wolterink, Oelixdorf (DE); Thomas Hänsel, Elmshorn (DE); Christian Greve, Itzehoe (DE); Frank Grewling, Breitenberg (DE); Karsten Stubbe-Thierer, Itzehoe (DE); Wolfgang Sievers, Kremperheide (DE); and Peter Morisse, Bornem (BE)
Assigned to Esko-Graphics Imaging GmbH, Itzehoe (DE)
Appl. No. 18/039,766
Filed by Esko-Graphics Imaging GmbH, Itzehoe (DE)
PCT Filed Nov. 30, 2021, PCT No. PCT/EP2021/083548
§ 371(c)(1), (2) Date Jun. 1, 2023,
PCT Pub. No. WO2022/117555, PCT Pub. Date Jun. 9, 2022.
Claims priority of provisional application 63/119,988, filed on Dec. 1, 2020.
Prior Publication US 2024/0017541 A1, Jan. 18, 2024
Int. Cl. G03F 7/20 (2006.01); B41F 33/00 (2006.01); B41M 1/04 (2006.01); G06T 7/00 (2017.01); G06T 7/13 (2017.01); B41N 1/12 (2006.01)
CPC G03F 7/2016 (2013.01) [B41F 33/0009 (2013.01); B41M 1/04 (2013.01); G03F 7/2053 (2013.01); G06T 7/0004 (2013.01); G06T 7/13 (2017.01); B41N 1/12 (2013.01); G06T 2207/30144 (2013.01)] 27 Claims
OG exemplary drawing
 
1. A method for minimizing voids in front of a trailing edge of a solid rendition or linework print region printed using a flexographic printing plate having a printing surface corresponding to information in an image file, the information in the image file including at least one solid rendition or linework image region corresponding to the solid rendition or linework print region, the at least one solid rendition or linework image region including micro-screen information comprising a pattern of “on” and “off” single pixels, the flexographic printing plate comprising a photopolymer cured through openings in a mask layer of the plate, the openings in the mask layer formed by an imager, the mask layer having a solid rendition or linework mask region corresponding to each solid rendition or linework print region, the method comprising providing mask micro-screen openings in an edge region of the solid rendition or linework mask region that have a different size than micro-screen openings in a center region of the solid rendition or linework mask region;
wherein the method comprises the steps of:
a) detecting in the image file, an image file edge region corresponding to the edge region of the solid rendition or linework print region;
b) detecting in the image file, an image file center region corresponding to the center region of the solid rendition or linework print region;
c) allocating a first laser light intensity to each “on” pixel in the edge region;
d) allocating a second laser light intensity to each “on” pixel in the center region; and
e) imaging the mask layer of the printing plate according to the information in the image file using the first laser light intensity for the edge region and the second laser light intensity for the center region; and
wherein the method further comprises determining an optimum value for the second laser light intensity for the image file, applying a predetermined ratio of second laser light intensity to first laser light intensity to determine a corresponding value for the first laser light intensity, and imaging the mask layer of the printing plate using the optimum value for the second laser light intensity and the corresponding value for the first laser light intensity.