• Journal of the Korean Graphic Arts Communication Society
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• v.27 no.1
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• pp.59-71
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• 2009

Measuring ink penetration is one of the best ways to know paper printability. Ink penetration was effected by physical properties of newsprint paper. This study was carried out for the purpose of improvement printability with ink penetration of domestic newsprint paper. The samples were prepared by means of 20 newsprint paper manufacture company in Korea, and were tested by IGT printability tester. The results of this experiments showed that the depth of ink penetration according to the printing pressure. The maximum points in ink transfer curve and the coefficients of oil absorption of the papers also depend mainly upon the situation of anchor points.

• Journal of the Korean Graphic Arts Communication Society
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• v.28 no.2
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• pp.45-56
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• 2010

The computer simulation is presented of gravure ink transferring behavior and penetration to the paper when an gravure roller is used to transfer a printing ink onto a substrate. The three dimensional unsteady ink motion is simulated by Polyflow package software and experimented by IGT gravure printing test machine. The simulation is performed where the flow domain is bounded above by a stress free surface and bounded below by a moving substrate. Specific predictions are made for particular pattern of cells and substrates. Cell size and ink rheological properties are found to be the principal determination of transferring behavior. Simulation is currently restricted to the flow domain beneath the receding meniscus. Both Newtonian and shear thinning inks are considered.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.3
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• pp.53-58
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• 2002

This paper was performed to investigate the effect of pore structure on ink residual behavior. To prepare different coating structures as substrates against inks, fine, medium and coarse calcium carbonate were used in the coating color. It is well known ink properties can affect to print qualities. After printing on the coated paper, ink layer can consider as third structure addition to paper and coating layer. To compare effect of ink properties on the surface structure and print qualities, several properties of ink were also adopted as raw material. Particle size of pigment effect on gloss evaluation of coated paper increased with calendering. It was shown that ink transfer rate increased as surface of the sample was smooth. The ink contained low viscosity resin evaluated more print gloss. Finer pigment particle size, smaller pore size and higher porosity. Pore volume of coated paper was slightly decreased with printing as the coating was prepared with the finest particle size. However, it founded that ink resin could not affect on pore volume and distribution of printed paper

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.4 s.117
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• pp.41-46
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• 2006

Printed mottle of coated paper is one of the most common but the most difficult problem in offset printing. Printed mottle is caused by an uneven penetration of Ink into the paper, binder migration, etc. For a high quality printing, development of new paper coating technologies to prevent print mottle is required. So for, the study of solving printed mottle is coated paper absorption controlled by base paper sizing and coating layer binder migration control. As a results, printed mottle has improved in coated paper. But printing is worked by interaction of printing ink, coated paper and printing pressure, then we need to understand of interaction printing work and coated paper. This research focused on a way of improving printed mottle by investigating various printing conditions such as ink dispersion, nip condition and amount of ink transfer using IGT printability tester.

• Journal of the Korean Graphic Arts Communication Society
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• v.25 no.2
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• pp.85-93
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• 2007

The printed mottle is recognized as the most common printing problems in using coated paper and one of the most difficult problems to solve in offset printing. Printed mottle is caused by an uneven penetration of ink into the paper and binder migration. The prevention of printed mottle requires of coating color formation, especially the minimum of binder migration. Printing worked by interaction of printing ink, coated paper and printing pressure. In this study, we investigated the effect of the properties changing of coated paper and printing conditions such as ink dispersion, nip condition and amount of ink transfer.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.1
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• pp.134-141
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• 2016

Dampening in printing is not only used with plain water but also used with various substances like dampening additive, in order to improve the wetting property by lowering the surface tension and to control material for modifing the ink transfer characteristic with proper emulsification. We have studied the printing quality according to these, looking into interrelationship among the dampening solution's pH, electrical conductivity and IPA content, prescribing the proper usage and minimum usage of fountain solution and dampening additive. In this study, it shows good result when mixing at the 7 wt% dampening with additive solution, which is result from the color density of printed sheets in accordance with the change of dampening solution condition. And the printed density value calculated 1 hour after printing, it shows relatively safe value at the etch liquid 4 wt% and IPA addition 2 wt%. The dry down at this test showed similar results regardless of various dampening conditions on coated paper, but in case of uncoated paper, the dry down showed a quite gap of different due to the fast penetration to the paper.