CPC B41M 1/04 (2013.01) [B41N 1/12 (2013.01); G03F 7/202 (2013.01); G03F 7/2053 (2013.01); H04N 1/405 (2013.01)] | 26 Claims |
1. A process for creating a mask for use in a process for making a printing plate from an unexposed flexographic plate having a masking layer disposed on a surface thereof, the mask comprising openings in the masking layer defined in accordance with imaging information, the openings configured to permit exposure of the unexposed flexographic plate to UV radiation during an exposure step, the process for creating the mask comprising:
(a) providing the image information as a first screen having a first plurality of pixels;
(b) defining the openings in the masking layer in accordance with the image information by:
(i) superimposing on at least a portion of the image information a second screen comprising a base pattern of equally sized spots, each spot corresponding to an imaged discrete element to be represented on the mask, each spot having a size corresponding to a smallest discrete element to be formed on the mask, the base pattern comprising spots aligned in horizontal rows having a non-zero horizontal spacing between adjacent horizontally aligned spots and vertical columns having a non-zero vertical spacing between adjacent vertically aligned spots, wherein the horizontal spacing between adiacent rows is equal to the vertical spacing between adiacent columns and for each spot defined in the base pattern of spots, each spatially nearest adiacent spot is aligned on center with the defined spot to define a diagonal line, the diagonal line having a slope defined by a vertical-rise-distance/horizontal-run-distance selected from the group consisting of: ½, −½, 2 or −2; and
(ii) removing portions of the masking layer corresponding to the imaged discrete elements to form the mask, including in at least a portion of the mask, selecting a size for forming each imaged discrete element such that each set of four neighboring imaged discrete elements has a non-imaged discrete area centered therebetween.
|