Author(s) | Collection number | Pages | Download abstract | Download full text |
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Baran N. V., Kukura V. V., Kukura Yu. A., Repeta V. B. | № 2 (59) | 11-21 |
The influence of the type and the lineature of the anilox rollers on the optical density of the imprints, the amount of ink on the imprints and on the raster dot gain has been studied in the manufacturing conditions. The optimum viscosity and content of additives in alcohol-soluble ink have been established for maximizing the efficiency of using GTT-engraving anilox rollers.
As a result of the experimental research of the flexographic printing process, it has been established that the use of S-type anilox rollers manufactured using GTT technology provides the optical densities of the imprints that are close to the anilox parameters with the lineature of 340 l/cm (5.5 cm3/m2), and L type anilox – close to the anilox parameters with the lineature of 160 l/cm (12 cm3/m2). The amount of ink transferred to the imprint for S and L type anilox is about 1.0 and 2.2 g/m2 and it is less than 15-25% relative to the corresponding anilox of traditional engraving. At the same time, the maximum dot gain of the raster elements on the imprints using S type anilox is 24-26% and is close to the anilox parameters with the lineature of 200 l/cm and higher compared to the anilox with the lineature of 340 l/cm.
It has been experimentally established that the reduction of the viscosity of the printing ink to 18-19 seconds positively affects the colour transfer of anilox rollers manufactured with GTT technology and increases the optical density of the imprints. The addition of methoxypropanol into the ink (up to 20%) significantly reduces (by 25%) the dot gain of raster elements on the imprints made using GTT-rollers.
The established regularities of the dependency of the flexographic imprints quality on the technological modes of the application of GTT-engraving anilox provide the opportunities for predicting the flexographic printing quality.
The results of experimental studies can be considered as practical recommendations for the effective use of GTT-engraving anilox rollers under specific manufacturing conditions, which will significantly improve the imprints quality.
Keywords: flexography, anilox rollers, GTT-engraving, imprints, optical density, dot gain.
doi: 10.32403/1998-6912-2019-2-59-11-21