• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.4 s.316
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• pp.17-25
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• 2007

Multilevel inkjet printer employs multiple ink droplets with variable dot size and/or different concentrations intended to preserve high fidelity color reproduction and the appearance of continuous tone. A variety of research efforts on multitoning techniques has progressed toward better image quality. However, banding artifacts appear due to the same dot distributions near the printable output levels. This results in discontinuity and visually unpleasing output, especially at the smooth tone transition region. In this paper, to reduce the banding artifacts, a multitoning method to arrange ink distribution by controlling the blending proportion of adjacent output pixels based on an improved threshold scaling function is proposed. Ink distributions across the banding regions are changed according to two factors of the threshold scaling function because these factors handle the blending point of adjacent output pixel. Therefore, 8 observers, subjectively investigated ink distributions around the printable output levels for a set of the improved threshold scaling function. For a threshold scaling function with the specific factor values, we can achieve smoother visual transition. In the experiment, the proposed method showed a reduction of banding artifacts in both u-ay and color image and represented better Performance of color reproduction.

• Clean Technology
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• v.7 no.3
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• pp.169-178
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• 2001

Textile printing prints around twenty bilion linear meters of textile each year. Rotary and flat bed screen printing requires pre and post treatments, leading to the loss of dyes and the environmental problems due to effluents. Digital ink jet printing can offer a solution to the existing problems, especially the environmental problems, in addition to its flexibility. Pigments are used as a dispersion inks in the digital inkjet textile printing. Molecular dynamic simulation like Stokesian dynamic simulation was employed to simulate the behavior of pigments and velocity distribution under the pressure driven flow in the printer nozzle. The simulation shows that the particle distribution in the flow are uniform if particle volume fraction is low, the ratio of nozzle and particle diameter is large, and the dimensionless average suspension velocity is low.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2001.04a
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• pp.76-76
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• 2001

종이가 가지는 공극 특성은 종이의 광학적 특성에 지대한 영향을 미칠 뿐만 아니라 인쇄용 지로서 사용될 때 잉크의 다공성 기질로서 잉크의 잔류 특성에도 큰 영향을 미친다. 특히 다공성 기지의 표변에 유동성이 뛰어난 물질이 가해 질 때, 이들의 유동 특성은 기질이 지 니고 있는 공극율과 공극의 분포에 따라 큰 차이를 나타내는 것으로 알려져 있다. 이러한 공극성은 백상지의 경우 사용된 펄프의 혼합 비율과 충전제의 사용량 그리고 펄프의 고해 정도에 따라 종이의 공극울이 달라진다. 종이의 공극성이 광학적 특성과 밀접한 연관성을 지니는 것은 종이의 광산란 계수를 결정하기 때문이다. 잘 알려진 바와 같이 종이의 광산란 계수는 빛의 산란과 관계되어 백색도와 백감도에 영향을 미친다. 그러나 도공지가 인쇄 용 지로 사용 될 경우, 도공지 표면에 도피되는 영크층은 도공지가 가지고 있는 구조적 특성을 변화시킬 수 있는 제3의 요인으로 간주 될 수 있다. 결국, 인쇄가 완료된 종이의 경우 원지층, 도공층 그리고 잉크층으로 구성된다. 따라서 다양 한 공극 구조를 가지는 기질위에 잉크가 도피될 경우 기질의 공극 특성에 따라 잉크 조성분 의 침투 거동에도 많은 차이가 있을 것으로 예측된다. 잉크의 구성 요소를 살펴보면 잉크의 색상을 결정하는 안료, 단일의 각 안료 입자를 도포하여 인쇄판으로부터 종이까지 운송시키 는 기능과 인쇄기에서 잉크의 유동성을 유지하고 종이 또는 기타 피인쇄체에 전이된 후에는 건조막을 형성하는 비히클 그리고 각종 기능성 첨가제로 구성되어 있다. 동일한 성분으로 구성된 잉크를 사용하여 각각 공극성이 다른 피인쇄체 위에 인쇄 될 경우 이들 조성분의 이 동과 표면 잔류 특성에 변화가 있을 것으로 생각된다. 즉 공극성이 풍부한 기질에 도피된 잉크는 반대의 경우와 비교하여 보다 많은 조성분이 종이의 공극 속으로 침투하게 될 것이 다. 이 과정에서 특히 미세한 안료 입자의 경우 피인쇄체의 표면 공극을 채우고, 비히클의 경우 미세한 공극속으로 침투되어 경화됨으로써 피인쇄체가 지니고 있는 공극량을 감소시커 게 될 것이다. 그리고 피인쇄체의 각종 형태의 공극으로 침투된 잉크의 양에 반비례적으로 피인쇄체의 표변에 잉크가 잔류하게 될 것이다. 따라서 본 연구에서는 여러가지 안료를 사용하여 각각 다른 공극 특성을 지니는 도공지를 제조한 후 이들이 가지는 공극 특성과 잉크의 잔류 거동에 대해 고찰해 보고자 하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.403-404
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• 2010

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.6
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• pp.243-249
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• 2018

Ceramic tiles, which were manufactured through high-temperature firing process at over $1000^{\circ}C$, are widely used as interior and exterior materials for building construction due to their excellent durability and aesthetic of surface glaze. In recent years, the introduction of digital ink-jet printing in ceramic tiles for architectural use has been rapidly proceeding, and studies on the materials such as ceramic ink, ceramic pigment, glaze have been actively conducted. In this study, the effect of microstructure change of surface glaze on the printing properties of ceramic inks was investigated by micronization of kaolin, which is the raw material of surface glaze. Black ceramic ink was used for ink-jet printing on the surface glaze of ceramic tile to evaluate the printability by measuring the size and roundness of the printed ink dot. The relationship between microstructure change of surface glaze and printability of ceramic ink was also investigated by analyzing the surface roughness and internal micropore distribution of surface glaze.

• Analytical Science and Technology
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• v.5 no.2
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• pp.217-222
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• 1992

An attempt was made to analyze green microstructure of AIN samples prepared by slip casting and dry pressing through Hg-porosimetry. Slip cast samples with narrow pore size distribation and high packing density showed higher sinterability and homogeneous distribution of second phase(s). Hg-porosimetry is and effective way to determine pore structure if "ink bottle" phenomenon does not occur. A comparison study with porosity measurement by quantitative microscopy showed that the effectiveness of Hg-porosimetry measurement could be extended to higher sintered density as long as pores remained open.

• Journal of the Korean Graphic Arts Communication Society
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• v.7 no.1
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• pp.65-72
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• 1989

Modified phenolics can have a retarding effect on the gelation of wood oil. Modified phenolic resins can be used in media for paint, varnishes, primers, overprinting varnishes, litho, letterpress and rotogravure inks. Varnishes based on rosin phenolic are faster drying, have better durability, are harder and glosser, and have greater resistance to water than ones based on ester gums. These physical properties is concerned with molecular weight distribution of rosin modified phenol resin. This paper was studied about molecular weight distribution of rosin phenolics which were prepared between $130~250^{\circ}C$. The results were as follows: 1) Average molecular weights inereased with increasing reaction temperature. 2) $M_w/M_n$ were from 3.43 to 46.44 with increasing reaction temperature and so the molecular weight distributions were changed from random distribution to broad distribution. 3) The relation ship between intrinsic viscosity and weight average molecular weight was follows: $[{\;}{\;}]={\;}1{\times}{\;}10^{-6}M_w,{\;}M_w=M_w$ 4) Esterification reaction between the acid group of rosin and polyol was started about $230^{\circ}C$$.

• Journal of the Korean Graphic Arts Communication Society
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• v.10 no.1
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• pp.55-67
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• 1992

The character of standing box printing reguires a rich representation on a light and a shade of color and cause the modern photographs to be abundant of the ink and also show the continuity of which any other printing is incapable because of its profound gradation.The clear printing in gravure can be said to be due to the good transfer of the ink-the completion of the transference of the ink into the stencil paper and the clear transference of the printing tone.The most inportant matter is the distance between the printing press and the doctor line. It is the matter of the structure and arrangement because of giving the most affect on the dryness of the ink in the cell.The glue of the ink in gravure changes by the kinds of the dye and the cellusolve used.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1446-1447
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• 2006

Electronics 분야에서 잉크젯 프린팅 배선 제작에 많이 사용되는 전도성 은 나노 잉크의 소성 특성을 연구하였다. 잉크젯 프린터를 이용하여 미세 배선을 인쇄하고, 열처리에 따른 비저항의 변화 양상을 관찰하였다. SEM을 통해 미세구조를 관찰하여 배선의 전기 저항과 미세 구조와의 상관관계를 고찰하였다. $250^{\circ}C$ 20분 동안 소성을 하였을 매 가장 낮은 비저항을 얻었으며 순수 은의 비저항 대비 약 2.6배였다. 또한 TEM을 통해 배선 내부의 pore를 관찰하였고, 그 분포올를 측정하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.6
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• pp.352-358
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• 2019

In recent years, printing paper with a function of information delivery and aesthetic value has attracted a great attention with increasing market demand for coated paper that is capable of high quality printing. The coated paper for inkjet printing with high-quality of photorealistic grades requires the coating layer with a good wettability and porous surface structure in order to improve the printability of ink. In this study, the coated paper was prepared using polyvinyl alcohol (PVA) and surface treated nano silica sol with silane coupling agent. It was confirmed that the coating layer with surface treated nano silica sol showed a uniform pore distribution and flat surface roughness. Glossiness of the prepared printing paper was similar to that of commercial high quality photo paper. Especially, the coated paper with surface treated nano silica sol showed improved printability with excellent roundness of the printed dot of ink. These results indicates that the coating layer with excellent wettability and uniform pore distribution can be formed by using the nano-silica particles with improved dispersibility through the surface treatment of the silane coupling agent.