• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.11
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• pp.992-998
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• 2009

We investigated the influence of organic solvents on the droplet properties of 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS-pentacene), which was used for semiconductor of organic thin film transistors (OTFTs) and deposited by ink jet printing. From the result of the investigation, the conditions of a suitable solvent is that boiling point should be above $200^{\circ}C$ to reduce coffee stain and the surface tension above 32 dyn/cm to decrease the droplet size. Consequently, we selected tetralin which have a high boiling point ($207^{\circ}C$) and high surface tension (34.3 dyn/cm) as the solvent for TIPS-pentacene, and applied it to OTFTs. In fabrication process the conventional bank process employing photolithography and etching process was replaced by ink jet printed bank process, resulting in simplifying the process. Especially, polyvinylphenol was used for the bank, and the high hydrophobicity could improve the confinement of TIPS molecules inside the bank, enhancing the performance over the conventional hydrophilic polyvinylalcohol bank. The mobility was $0.18\;cm^2/Vs$, current on/off ratio $2.09{\times}10^5$, subthreshold slope 0.42 V/dec, and off state current $0.049\;pA/{\mu}m$.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1583-1585
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• 2007

The purpose of this research is to control proper processing condition of RGB photo resistant in the ink-jet process increasing processing ability by adding additives. The viscosities of modified RGB photo resistant were $10{\sim}14cps$ and the additives could decreased agglomeration and flowing trace of photo resistant effectively. Another way, the adhesion between photo resistant and glass substrate was improved by modifying photo resistant and substrate. The surface tensions of modified photo resistant were same as that of original RGB photo resistant. The additives appeared a better compatibility with photo resistant, and the micelle of photo resistant did not be broken during modified process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.332-332
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• 2010

We have successfully demonstrated the inkjet printing method to create $Al_2O_3$ films withouWe have successfully demonstrated the inkjet printing method to create $Al_2O_3$ films without a high temperature sintering process. In order to remove the coffee ring effect in the ink drop, we have introduced a co-solvent system in order to create Marangoni flow in the ink drop, which leads to the dense packing of ceramic powders on the substrate during inkjet process. The packing density of the Inkjet-printed $Al_2O_3$ films is around 60% (max. 70%) which is very high compared to the value obtained from the same material films by other conventional methods such as film casting, dip coating process, etc. The voids inside the films (which are around 40% of the entire film volume) are filled with the polymer resin (Cyanate ester) by the infiltration process. This resin infiltration is also implemented by the inkjet printing process right after the Ah03 film ink-jetting process. The microstructures of the printed $Al_2O_3$ films are investigated by Scanning Electron Microscope (SEM) to understand the degree of packing density in the printed films. The inkjet-printed $Al_2O_3$ films have been characterized to investigate its thickness and roughness. Quality factor of the printed $Al_2O_3$ film is also measured to be over 300 at 1MHz.

• Journal of Aerospace System Engineering
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• v.12 no.6
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• pp.1-8
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• 2018

ACF, which is used for the transparent electrode film is manufactured by the thermocompression method with conductive particles. However, the method has disadvantages since there are many wasted materials and the process is complex. To overcome the demerits of the conventional method, EHD printing technology with conductive particles ink is proposed. The line thickness of patterning is influenced by the characteristics of the inks and the printing conditions. Therefore, it is salient to find the most conducive conditions for the micro patterning. In this paper, the ink with conductive particles was manufactured, and the patterning results were obtained by varying the nozzle thickness and the flow rate. The electrical conductivity according to the ejection of the particles ink is obtained.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.04a
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• pp.39-64
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• 2003

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.2
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• pp.1-12
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• 2002

Starch dissolved in paper-mill wastes, either as a result of poor retention on the paper web or recycling of surface-treated broke, was a major pollutant Laboratory tests were performed by using different kinds of starch as a surface treatment. It was concluded that the use of cationic starch can positively affect the level of starch dissolved in liquid effluents. When cationically modified starches were used for surface sizing, the starch was tightly bound to the paper fibers, it was not removed during the repulping of broke. The result of mill trial in fine paper manufacture for the application of low-viscosity cationic starches used in size press reduced COD load in the effluents and increased One Pass Retention. It had been found that when cationic starch used as a surface sizing agent, more starch was retained on or near the surface of the sheet than with conventional oxidized starches. Thus surface strengths and quality were improved. In addition it is possible to maintain the desired level of starch penetration into the fiber net and improve porosity, opacity and brightness. In contrast, in most cases, dusting problems are notably eliminated. Cationic surface sized starch improved black and color ink-jet print quality in terms of feathering and optical density of the print image. These improved properties were believed to be due to a combination of fiber bonding and surface orientation more uniform starch concentration on the paper surface was resulted. Moreover cationic charges in the paper surface lend themselves excellently to fix ink jet ink anionic in nature.

• Electrical & Electronic Materials
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• v.11 no.4
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• pp.350-354
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• 1998

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.04a
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• pp.65-91
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• 2003

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.106-110
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• 2005

• Journal of the Korean Graphic Arts Communication Society
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• v.25 no.1
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• pp.81-94
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• 2007

Recently, the trend in the printing industry includes shorter run lengths and with fast turnaround times. As new markets have made it possible to produce small quantities of high-quality color products at affordable price, the general commercial printing meets the customer's diverse demand by using spot color besides process four colors. Especially, by using spot color for printing the enterprise's logo or specific color, we can see the effect of printing is getting better. With the combination of the right software, ink, media, and device can be treated as a digital proofer for spot color printing, providing significant time and cost savings compared to conventional procedures. The objective of this study is to investigate the quality of spot color proofs printed by ink-jet and dye sublimation proofer using ICC-based color management system. An Epson Stylus Color 3000 ink-jet proofer combined with Best Color Proof XXL RIP was tested for glossy and matte paper. 3M Rainbow dye sublimation proofer was examined using 3M Rainbow controller ver. 4.1 RIP on the manufacturer recommended proofing paper. ICC profiles were generated for each device using ECI 2002 visual target and evaluated for the accuracy of process 4 color reproduction. The test charts consisting of Pantone color 1140 was selected to test the quality of spot color reproduction.