• The Journal of the Korea Contents Association
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• v.15 no.1
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• pp.74-85
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• 2015

This study on the proofing what used to correct the color difference between the photo image and offset press. Printing photos with color offset press always make the differs, because of the difference in gamut. Photographer hopes to be able to use the proofing with inkjet printer for reduce these differences. In this study, I experiment with various ways for the proofing by photographer directly. It is using the ink jet printer and image outputs of the various mode was applied to a variety of color setting value. And calculate the output image using a spectrophotometer and compared with the image of offset press. At last I can found a very similar color setting value with the offset image. After all this research is to obtain a result of finding out proofing work flow through method to measure and how to apply various color setting value results.

• Journal of the Korean Graphic Arts Communication Society
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• v.21 no.2
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• pp.31-42
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• 2003

The optimum color proofing system with the similar colorants to the printing system has to be used in high quality offset color printing. And so, the evaluation on color reproduction properties of the colorants for proofer and press are very important. In this paper, the optimum color proofing method is recommended by means of colorimeric comparative evaluation on the color reproduction properties such as color gamut, color difference, hue error of the colorants for the proofing system of CRT monitor, inkjet printer, dye sublimation type digital proofer, and the actual printing system of offset press.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.1
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• pp.52-60
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• 2009

A printing defect known as fluting (or waviness) of the web printed by heatset web offset printing process is one of the chronically serious problems deteriorating print quality. In this paper, fluting occurrence on uncoated papers was explored in terms of many printing conditions including drying temperature, fountain solution amount, ink supply, and press configurations. For this purpose, fluting on prints from real press runs was appraised in a quantitative manner. As results, ink supply was a distinctive factor for fluting such that the lower ink amount, the milder fluting. However increase in fountain solution seemed to make fluting severer while the effect of drying temperature was inconsistent for each paper. This result might indicate variable drying requirements for each paper. Thereby it was suggested that the optimum drying conditions related to the printabilities of each paper need to be established to minimize fluting potential. A press with short dryer and drastic cooling unit produced higher fluting. Suggestions for future work were given along with interpretation for the results.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.04a
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• pp.132-145
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• 2006

In order to improve the printability for offset print in Korea, the experimental printing was performed with commercial press. The clue of this study is that the printing condition of the imported machines are not set properly for the Korean printing materials. Although almost all of the printing machines are imported, printing materials have to be supplied in Korea. So we need to study on the printability between Korean materials and imported machines. In spite of difficulties in experiments with commercial press, three newsprint machines and three commercial printing presses were used for this study over 5 years. As the results, the optimum range and printability coefficients were obtained.

• Journal of the Korean Graphic Arts Communication Society
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• v.24 no.1
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• pp.45-57
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• 2006

Offset lithography is the most widely used printing process in domestic printing industry, but there are no industry-wide specifications for press control to assure consistent quality across printing plants. As printing becomes more of a commodity and less of an art, it is necessary to develop a print quality specification standard suitable for Korea offset printing field. This study aims to contribute to improving the quality of domestic offset color prints by comparative study on color reproduction properties of 2 kinds of domestic process color ink composed of C(cyan), M(magenta), Y(yellow) and K(black) and of 3 kinds of domestic coated paper, using colorimetric color measurement method.

• Journal of the Korean Graphic Arts Communication Society
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• v.23 no.2
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• pp.77-92
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• 2005

Offset lithography is the most widely used printing process in domestic printing industry, but there are no industry-wide specifications for press control to assure consistent quality across printing plants. As printing becomes more of a commodity and less of an art, it is necessary to develop a print quality specification standard suitable for Korea offset printing field. This study aims to contribute to improving the quality of domestic offset color prints by comparative study on color reproduction properties of 3 kinds of domestic process color ink composed of C(cyan), M(magenta), Y(yellow), and K(black), and of 3 kinds of domestic coated paper, using densitometric color measurement method.

• Journal of the Korean Graphic Arts Communication Society
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• v.14 no.2
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• pp.21-36
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• 1996

With increased use of halftone dot overprints for offset color printing, it is important to study the density and ink trap of the overprints. In this research the equation to predict the density and the method to evaluate ideally the fractional ink trap are preposed. And also the halftone dot overprinting experiments of Magenta over Cyan or Cyan over Magenta under wet-on-wet or wet-on-dry overprinting using 2-color offset press show the above proposals are reasonable, and show the effect of overprinting sequence on the density and ink trap.

• Proceedings of the Korean Printing Society Conference
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• 2007.11a
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• pp.29-43
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• 2007

Web offset newspaper prints is the most widely used printing process in domestic printing industry, but there are no industry-wide specifications for press control to assure consistent quality across newspaper printing plants. As newspaper printing becomes more of a commodity and less of an art, it is necessary to develop the print quality specification standard suitable for Korea web offset newspaper printing field. There are a few commonly employed printing standards such as, SNAP(Specification for Non-Heatset Publication) of the US, IFRA(INCA-FIEJ Research Association), J-color (Japan printing machinery association). And there exists KS for domestic standards, however, since it has been directly imported from ISO standards, there are discrepancies in printing materials and media. This paper aims to examine the color reproduction quality of domestic web offset newspaper prints by comparing with foreign standards. Printing experiments on this study have been performed at one of the domestic newspaper printing companies. The color reproduction properties of the web offset newspaper prints are measured by means of densitometry and colorimetry. These measures are evaluated comapratively with the international standards by means of analyzing, the major factors that determine the color reproduction quality of web offset newspapar prints.

• Journal of the Korean Graphic Arts Communication Society
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• v.25 no.1
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• pp.27-41
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• 2007

Web offset newspaper prints is the most widely used printing process in domestic printing industry, but there are no industry-wide specifications for press control to assure consistent quality across newspaper printing plants. As newspaper printing becomes more of a commodity and less of an art, it is necessary to develop the print quality specification standard suitable for Korea web offset newspaper printing field. There are a few commonly employed printing standards such as, SNAP (Specification for Non-Heatset Publication) of the US, IFRA(INCA-FIEJ Research Association), J-color (Japan printing machinery association). And there exists KS for domestic standards, however, since it has been directly imported from ISO standards, there are discrepancies in printing materials and media. This paper aims to examine the color reproduction quality of domestic web offset newspaper prints by comparing with foreign standards. Printing experiments on this study have been performed at one of the domestic newspaper printing companies. The color reproduction properties of the web offset newspaper prints are measured by means of densitometry and colorimetry. These measures are evaluated comapratively with the international standards by means of analyzing, the major factors that determine the color reproduction quality of web offset newspaper prints.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.215-225
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• 2006

Today's requirements for print-press runnability and print quality demand an optimised absorption and adhesion of printing ink on the paper surface. Modern coating concepts for high glossing offset grades use ultra fine pigments, whereas binder level has continuously been decreased to a minimum in recent years to achieve the highest possible sheet gloss development and for economical reasons. Both the ultra fine pigments and the reduced binder levels lead in many cases to a faster ink setting rate. On the other hand, matt paper grades use relatively coarse pigments leading to a slow ink setting compared to the high glossing papers. Both too fast and too slow ink setting properties implicate drawbacks in print quality and print press runnability. The mechanisms behind the interactions between ink and coating have been presented in many previous publications. The purpose of this study was to determine and quantify how the ink setting rate is influenced by pigment system (GCC and GCC/clay blends), latex level and latex properties in the topcoat of double coated sheet fed offset paper. The roles of binder level and type in the precoat were also assessed. The effect of calendering (temperature and pressure) was studied with one formulation. The resulting ink setting characteristics were tested using three different laboratory testing instruments. The correlation amongst the different laboratory testing methods is discussed. The results show that by varying the latex properties, the pigment system and/or latex addition level, the ink tack development of ink applied to a topcoat pigment system can be significantly influenced. It can be slowed down as often desired with ultra fine pigments or speeded up in the case of coarse pigments. There was no visible effect on the ink setting rate by using different binder systems in the precoat..