Earticle

The Rheological properties are important factors in printing process. Specially, emulsification phenomenon is a very important factor that decides the quality of printing products in lithography. In this paper, I investigated the flow characteristics depending on calcium carbonate concentration for emulsified inks. By applying the data of this paper, I which to predict quality of printing product in practical printing process.

In gravure printing, all of the ink in the gravure cells does not leave the cell onto the substrate. The ink transfer from plate to paper in the gravure printing was simulated by computer. A few studies have dealt with cell withdrawal with simplified Newtonian flow models however, this work was performed with the non-Newtonian inks with different simulation software.

In Flexo printing machine, it's operated with combination of blanket cylinder and cylinder. The blanket cylinder has some number of grooves to attach the blanket on surface. In case of operating the printing machine, it has generate mechanical noise when the two cylinders encounter with the grooves. So, in this study, we developed a mechanical noise control algorithm of printing in servo control system. Then we have reduced the mechanical noise with control of servo actuator.

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.

As information-communication network has been developed rapidly, internet users' circumstances also have been changed for the better, in result, more information can be applied than before. At this moment, there are many differences between real color and reappeared color on the CRT. When we observe a material object, our eyes perceive the multiplied form of light sources and nature spectral reflection. However, when the photographed signal is reappeared, illumination at that time of photographing and spectral reflection of a material object are converted into signal, and this converted RGB signal is observed on the CRT under another illumination. At this time, RGB signal is the reflected result of illumination at that time of photographing Therefore, this signal is influenced by the illumination at present, so it can be perceived another color. To accord the colro reflections of another color source, the study has been reported by S.C.Ahn, which study is about the color reapperarance system using neuron network. Furthermore, color reappearing method become independent of its circumstances has been reported by Y.Miyake. This method can make the same illuminations even if the observe circumstances are changed. To assume the light sources of observe circumstances, the study about color reappearing system using CCD sensor also have been studied by S.C.Ahn. In these studies, a population is fixed, first, on ab coordinates of CIE Lab. Then, color reappearing can be possible using every population and existing digital camera. However, the color is changed curvedly, not straightly, according to value's changes on the ab coordinates of CIE Lab. To solve these problems in this study, first of all, Labeling techniques are introduced. Next, basis color-it is based on Munsell color system-is divided into 10 color fields. And then, 4 special color- skin color, grass color, sky color, and gray-are added to the basis color. Finally, 14 color fields are fixed. After analyzing of the principle elements of new-defined-color fields' population, utility value and propriety value are going to be examined in 3-Band system from now on.

A novel evaluation method is investigated for UV curing process in printing system. The method is based on the measurement of conducivity change by the photopolymerization of UV curable inks and paints. It is found that the decrease of conductivity is caused by photopolymerization of epoxy monomer during UV curing process of ink film and the by the rate of UV curing. It is possible to make the dynamical evaluation the curing rate of UV curable ink in curing process by this method.

Barrier ribs for PDP(plasma display panel) are commonly utilized to have uniform height and width and to prevent opical crosstalk between adjacent cells. The requirements for such barrier ribs are uniform height and shape, low outgassing rate and low porosity, high aspect ratio, and fine resolution. In this study, we are studied about that to make efficiency of material and high quality barrier ribs for PDP. As a result, could got high barrier ribs of evenly in 1th phenomenon using watersoluble UV curing resin and know that flatness of upper part is also very good.

Printing inks are mainly composed of pigment and vehicles. Among these components, the Vehicle affect the rheologic property of the ink the most but pigment content of characteristic also after to the fluidity property not less than the vehicle. In the study, It is tested effect to the ink fluidity and structure recovery according to change the pigment particle size. The ink fluidity have been observed by using rheometer at the various conditions and it has been tested to observe what the ink fluidity has different means. In result We have found that the viscosity value of the low shear rate range has relatively higher value with decreasing the pigment particle size in the ink. Also, it has been found that when the pigment particle size decreases, the yield stress gradually increase. In the case of ink's structure recovery, when the pigment particle size decreases in the ink, the less changing shear rate, and it takes less time to recover.

We have reviewed the method for surface tension of printing inks. Most of the methods fir for the low viscosity inks and solvents for inks. However, the inks for the offset lithography and intaglio should have high viscosity and high tack. The elongation of the ink filaments has more effect on the measuring surface tension than the energy of the surface molecules. In this paper, we propose the elongation method to estimate the surface tension of high viscosity printing inks. Even though we could measure the surface tension for low viscosity inks such as gravure and screen, elongation method could more useful to estimate the surface tension of lithography and intaglio inks than any other methods.

We synthesised 1,3-Diphenyl-5-pyren-2-yl-4,5-dihydro-1H-pyrazole(DPP) and investigated its optical properties. The structure of DPP was confirmed by GC-Mass and elemental analysis. The absorption and photoluminescent spectra of DPP were measured at both hydrophobic and hydrophilic solvents and by the stokes shifts of DPP Lippert's equation could be applied. The results showed linear relation between and [(ε-1/2ε+1)-(n2-1/2n2+1)] and ( μg - μ e )2.