• 한국전산유체공학회지
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• 제17권3호
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• pp.33-38
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• 2012

The droplet ejection behavior from drop-on-demand printhead are investigated numerically for Newtonian and shear-thinning fluid. The numerical simulation is performed using a volume-of-fluid model. In this study, we compare the printable range in terms of Z number and pinch-off time for Newtonian and shear-thinning fluids. The printability range are found to be 1.08 $$\leq_-$$ Z $$\leq_-$$ 12.9 for Newtonian fluid and 0.8 $$\leq_-$$ Z $$\leq_-$$ 12.9 for shear-thinning fluid. However, air entrainment is observed during merging of primary and satellite droplet within the printability range. The pinch-off time of the shear-thinning fluid is apparently shorter compared to the corresponding Newtonian fluid due to shear-thinning effects and the differences in the pinch-off time is enlarged significantly when the capillary number is larger than 0.5.

• 펄프종이기술
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• 제44권3호
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• pp.41-48
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• 2012

Materials used for the inks in the printing industry is an important material following the paper. The composition of the ink is pigment and organic solvents. However, Ink is used in a variety of chemicals, they are classified as non-green. Therefore, rosin-modified phenolics manufactured by the reaction of phenol and formaldehyde can take the place of eco-phenol free resin and by experiment density, gloss, trapping, contrast and dot gain of printing has been studied as printability. The result of study can support that the properties of printing using eco-phenol free resin such as density, gloss, contrast and trapping is similar to existing ink. In the part of dot gain, the result is excellent. So we were thought to be able to improve some characteristics such as dispersion of black ink, that will be possible for the field applicability.

• 펄프종이기술
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• 제32권3호
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• pp.39-47
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• 2000

This study was carried out to investigate the effect of the type of base papers containing Sw-BDP, HW-BDP and Bamboo-BKP on the properties and printabilities of coated papers. Also it was intended to evaluate the effect of coated paper prepared with anionic and amphoteric latex based coating color. The results obtained from this study were as follows. The fiber length of Bamboo-BKP was observed longer than that of the Hw-BKP and shorter than that of the Sw-BKP. This has effect on physical properties. Therfore the results of mea-suring physical properties were higher ratio of Sw-BKP physical properties tended to be slightly higher with the increase I the mixing ratio. Considering the optical properties of base papers the highest opacity was obtained in case of the Hw-BKP and the second appeared Bamboo-BKP. On the other hand smoothness roughness and air permeability of Bamboo-BKP were lower than those of wood pulp and the optical properties of coated papers tended to show the similar with those of base papers. The ink receptivity and print gloss of the coated papers for Bamboo-BKP were lower than those of wood pulp. As the mixing ratio of Sw-BKP was increased the properties and printabilities were improved slightly. Meanwhile amphoteric latex was improved the optical properties and printability of coated papers.

• 한국인쇄학회지
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• 제30권2호
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• pp.59-68
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• 2012

As one of the eletronic device industries has been developed by using a recent printing method, the consumption of Ag paste has been on the rise as well. The printing method has simple processes in comparison with other methods. Also it enables to be large-scaled and to lower price ranges. If UV curing system would be applied to the printing method, energy consumption and dangerousness from curing system can be minimized in a short period of time so that its method can be more eco-friendly. This study conducted an experiment in order to make UV curing Ag paste which is feasible to implement micro patterns with different dispersing agents. The purpose of the study is to analysis the suitable printability for micro pattern and to test dispersibility, hardening properties, conductivity and adhesive stength by measuring viscosity, TI(thixotropy index), G', G", $tan{\delta}$(G"/G') after making paste. We have experimented with four dispersing agents. After We did an analysis of characteristic of rheology, conductivity and adhesive stength, etc, We confirmed that the paste added FP 3060 has excellent dispersibility, conductivity and adhesive stength. If the paste has excellent dispersibility, we will expect that micro pattern is made by that.

• Advances in concrete construction
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• 제13권4호
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• pp.281-289
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• 2022

3D printing cement-based materials (3DPCBM) is an innovative rapid prototyping technology for construction materials. This study is tested on the rheological behavior, printability and buildability of steel slag (SS) content based on the extrusion system of 3D printing. 0, 8 wt%, 16 wt%, 24 wt%, 32 wt% and 40 wt% SS was replaced cement, The test results revealed that the addition of SS would increase the fluidity of the printed paste, prolong the open time and setting time, reduce the plastic viscosity, dynamic yield stress and thixotropy, and is beneficial to improve the pumping and extrudability of 3DPCBM. With the increase of SS content, the static yield stress developed slowly with time which indicated that SS is harmful to the buildability of printing paste. The content of SS in 3DPCBM can reach up to 40% at most under the condition of satisfying rheological property and buildability, it provides a reference for the subsequent introduction of SS and other industrial solid waste into 3DPCBM by explored the influence law of SS on the rheological properties of 3DPCBM.

• 공업화학
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• 제9권7호
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• pp.961-967
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• 1998

종이제조에 있어서 종이의 광학적 성질 및 인쇄적성을 개선하기 위하여 여러 종류의 충전제가 사용되고 있다. 본 연구는 신문용지 제조에 있어서 여러 종류의 충전제, 즉 경질탄산칼슘(PCC), 중질탄산칼슘(GCC), 그리고 혼합된 충전제(PCC+미세활석(MVP) 또는 활석(talc), GCC+MVP 또는 talc))를 종이에 충전시켰을 때 종이의 여러 물성에 미치는 영향을 검토하였다. 얻어진 결과를 요약하면 다음과 같다. 1) 충전제를 지료전건중량당 5% 처리시 동일 처리조건하에서의 충전제 보류율은 PCC 처리시 GCC 처리시보다 16.8% 정도 높게 나타났으며, PCC 및 GCC를 처리했을 때 모두, 배합한 충전제의 입자경이 커질수록($PCC{\leq}GCC<MVP<talc$) 보류율이 증가하는 경향을 나타내었다. 2) PCC 처리시 무처리보다(92.2%) 대비 2.3% 이상의 비교적 높은 불투명도 개선효과를 나타내었으며, 배합한 충전제의 평균 입자경이 클수록 불투명도가 감소하는 경향을 나타내었다. 3) PCC 단독 처리시 GCC 단독 처리시보다 소폭의 인열강도 하락을 나타내었으며 20% 배합처리한 충전제의 평균 입자경이 커질수록 인열강도가 증가하는 경향을 나타내었다. 4) PCC 단독처리시 비교적 높은 인장강도를 나타내었으며, 다른 충전제와 혼합처리시 인장강도의 하락폭은 GCC 처리쪽이 적은 것으로 나타났다. 5) PCC를 처리하였을 경우, 배합한 충전제의 입자경이 커질수록 ($PCC{\leq}GCC<MVP<talc$) 파열강도는 직선적으로 감소하였다. 6) 충전제를 처리하였을때 무처리보다 비교적 우수한 인쇄적성 효과를 나타내었다.

• 한국결정성장학회지
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• 제29권6호
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• pp.345-351
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• 2019

디지털 잉크젯 프린팅 기술은 고해상도, 빠른 인쇄 속도, 높은 잉크 효율과 같은 장점과 함께 다양한 소재 적용이 용이하여 반도체, 디스플레이, 세라믹 타일 등의 산업 분야에서 주목을 받고 있다. 최근에는 전통적인 잉크 소재에서 벗어나 우수한 내열성, 내광성, 내화학성 등을 보이는 기능성 소재도 잉크젯 프린팅 공정에 적용하려는 시도가 활발히 진행되고 있다. 특히 2차원 인쇄뿐만 아니라 3차원 적층인쇄에 관한 연구도 시작되고 있으며 이를 위해서는 토출되는 잉크의 유변학적 물성과 프린트되는 기판과의 상호작용를 제어하는 것이 필수적이다. 본 연구에서는 나노 실리카 입자가 포함된 광경화성 세라믹 잉크를 합성하고 잉크의 물성과 프린팅 기판의 표면특성을 제어하였다. 나노 실리카 입자가 포함된 광경화성 세라믹 잉크의 퍼짐현상을 억제하고 기판과의 접촉각 특성을 개선함으로써 결과적으로 프린팅 해상도 및 적층성을 향상시켰으며 잉크젯 프린팅을 이용한 광경화 나노 실리카 잉크의 3D 프린팅에 대한 가능성을 확인하였다.

• 한국결정성장학회지
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• 제28권6호
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• pp.243-249
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• 2018

$1000^{\circ}C$ 이상의 고온 열처리를 통하여 제작되는 도자타일은 우수한 내구성과 표면 유약의 심미성 때문에 건축용 내외장재로 많이 사용되고 있다. 최근 건축용 도자타일 공정에 양산형 잉크젯 프린팅이 빠르게 도입되고 있으며, 이와 관련한 소재(세라믹 잉크, 세라믹 안료, 유약)에 대한 연구가 활발하게 이루어지고 있다. 본 연구에서는 도자타일의 표면 유약의 원료인 고령토(kaolin)를 고에너지 밀링을 이용하여 미립화하였고, 이에 따른 표면 유약의 미세구조 변화가 세라믹 잉크의 인쇄적성에 미치는 영향에 대해 확인하였다. 세라믹 잉크는 자체 제작한 검은색 잉크를 사용하여 도자타일의 표면 유약에 잉크젯 프린팅하였다. 프린팅된 세라믹 잉크 망점의 크기, 진원도를 측정하여 표면 유약의 고령토 미립화에 따른 인쇄적성을 평가하였다. 또한 고령토 미립화에 따른 표면 유약의 거칠기와 내부 미세 기공 분포를 측정하여 표면 유약의 미세구조 변화와 세라믹 잉크의 인쇄적성의 관계에 대해서도 고찰하였다.

• 한국인쇄학회지
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• 제12권1호
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• pp.57-68
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• 1994

In the last decade, digital image processing technics have been rapidly developed according to the advancement of electronic technique, and total scanner and DTP system were developed. Specially, there is need to retouch the color and image on the CRT. In this paper, we described a method to display surface color of printing on the CRT, and an algorithm to simulate the color reproduction by offset printing. The experimental results show that the described method and algorithm are useful and valid on the computer simulation of the multi-color printing adapted process ink characteristics.

• 펄프종이기술
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• 제30권1호
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• pp.95-103
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• 1998

Many new technologies and developments designed to increase paper machine speeds and improve paper printability have emerged in recent years. These improvements have changed the structure of paper and given winder manufacturers new challenges, especially as the requirements of printing presses have also changed. Ever-increasing roll widths and diameters are needed. Along with faster press speeds and shorter acceleration times, the unwinding of roils in the press room has become a true test of paper strength and roll structure, In the following we will review the special winding features of coated papers and discuss a selection of the winder type to meet a mill's specific needs.