Original scientific paper
Analysis of Dot Gain Produced by Interactions of Flexographic Plate and Anilox Roll Screen Frequencies
Ramesh R. Dendge
orcid.org/0000-0001-9842-3199
; Government Institute of Printing Technology,
Abstract
Flexography prints on non-absorbent as well as absorbent substrates using liquid ink. With
developments in photopolymer plate and anilox roll manufacturing technology, we can print half
tone with screen frequencies exceeding 150 LPI (Lines per Inch) where the print quality can be
comparable with offset printing results. This has helped flexographic printer to reproduce the blackand-
white, single colour tone and full colour graphic original, satisfying the printing and packaging
needs of many customers. But unlike other printing technologies in flexographic printing screen
frequency of plate i.e. image carrier and engraving line frequency of anilox roll collectively affect
the smoothness and uniformity of reproduced half tone image. Furthermore, the LPI of the screen
used in plate making also adds to variation in tonal reproduction. In the presented work 3 line
frequencies expressed in CPI (Cells per Inch) of anilox roll and 5 screen frequency of image carrier
are selected and their effect on print characteristics is studied using the plot of theoretical dot area
against apparent dot area. Given the sizable capital investment involved in manufacturing of anilox
roll, this work is directed at finding the optimum combination of screen frequency and line frequency
required to achieve tonal balance.
Keywords
Half Tone Screen Frequency, Dot Area, Dot Gain, Anilox Roll Line Frequency, and Dot Gain Curve.
Hrčak ID:
300911
URI
Publication date:
28.4.2023.
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