• Journal of the Korean Graphic Arts Communication Society
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• v.30 no.2
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• pp.23-33
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• 2012

With the development of many display technologies currently applied to them in the field of printed electronics, there have been many researches that high resolution printing for thin and uniform pattern. In this paper, printing ink flow properties in the reverse offset mechanism were simulated. The aim of this research is to expect the ink flow behavior between cliches to make fine pattern by a printing technique which is a reverse offset. The simulation results show that almost the same as the experiments and the flow behavior according to the ink film thickness and printing pressure changes could be expected.

• Journal of Engineering Education Research
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• v.21 no.6
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• pp.90-98
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• 2018

This paper proposes a framework of engineering education for product development processes based on product data management (PDM) software and 3D printing. The PDM software supports the product development process-oriented educational coursework, collaborative team projects and project-based learning environment. The 3D printing supports the prototyping step in the product development process and helps participants consider physical realization of their designs during the product design and development phases. The framework was implemented in an introductory course for engineering students to product design and development, and author found that it is important to support rich communication among participants including lecturers, teaching assistants and students to enhance the quality of education and to overcome the burden of learning various computer-aided tools and 3D printing techniques needed for the framework.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.5
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• pp.143-148
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• 2018

3D printing has been expanding beyond the bio/nano field to the automobile and aviation industries. 3D-printing technology has to overcome real problems to have economic value compared to its unlimited usability. Typically, the difference in mechanical strength along the lamination direction requires sufficient research to ensure reliability. In this paper, we study the anisotropic properties of ABS based on the stacking method of FDM 3D printing. Specifically, the mechanical properties of ABS material are determined through a tensile test and 3-point bending test, and the in-plane orthotropic properties are ascertained.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.188-190
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• 2004

As an effort to reduce cost and lead-time and to increase flexibility and responsiveness, manufacturers are using digital printing in numerous process steps. Typically, these processes require the precise dispensing of various fluids. Piezo ink jet printheads are proving to be reliable tools for depositing active materials such as light emitting polymers (LEP) for mobile phone displays and color filter inks for liquid crystal displays. Ink jets are also being used to provide uniform coatings of polyimide alignment layers and spacers for LCDs. Success with legend printing on PCBs using ink jets has encouraged the design of equipment for directly printing both etch resist and solder mask for PCBs. Development of printers for passive components such as capacitors and resistors is underway. This paper will present the attributes of an ink jet printhead designed to a precision deposition tool and discuss how it is being used to digitally print electronic and flat panel display components. Status of commercialization of digital printing will be discussed along with issues to be resolved before wide adoption takes place.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.3
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• pp.1-11
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• 2007

To evaluate the quality of waste paper used for the manufacture of linerboard, the types of papers and foreign materials in compressed waste paper currently used were investigated. The recycled fibers were obtained from printing paper, newspaper, wrapping paper, white coated paperboard and corrugated container. Their fibers were observed by using a microscope, and the mechanical properties of the recycled papers manufactured from the recycled fibers were investigated. The compressed wastepaper was composed of 54% paperboard, 20% printing paper, and 20% newsprint. The content of foreign materials was about 4%, showing higher contents compared to 1% of foreign substances provided by Korea paper manufacturers' association. The types of foreign materials were various, which include vinyls, plastics, metals, woods, styrofoams, and cloths. Sound fibers were generally observed in the recycled fibers of printing papers and wrapping paper. The recycled fibers of white coated board, corrugated container and newsprint showed to be generally damaged. The whiteness of each recycled fiber were highly affected by pulp bleaching and ink-particle mixing conditions. The values of breaking length and burst index were lower than those for corrugating medium and liner board specified in KS. Although the anatomical characteristics of recycled fibers varied, their strengths appeared to be similar. This result may be explained by the use of non-deinked fiber.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.1 s.119
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• pp.25-29
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• 2007

Print mottle is the spotty and cloudy appearance of the ink on the substrate. Print mottle is influenced significantly by the characteristics of the paper with regard to homogeneity of its structure and its coating. The print mottle can be counteracted, in particular by altering the absorption characteristics of the inks, by changing sequence in which the inks are printed, or by using a advanced coated paper. In this study, we investigated the effect of ink dispersion to the print mottle through trial printing test and also analyzed the correlation between properties of coated paper and subjective results by statistic method. The result of this study is expected to be applied the basic data to solve the problem of printing mottle.

• Journal of the Korean Graphic Arts Communication Society
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• v.12 no.1
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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.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.651-653
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• 2008

In this paper, we report electrical properties of OTFTs by using ink-jet printing with polyvinylphenol (PVP) for gate insulator and bis(triisopropylsilylenthynyl) pentacene (TIPS pentacene) for semiconductor. OTFTs produced the excellent performance with the mobility of $1.27\;cm^2/V.s$ for top contact structure(TCS) and inverter consisting of two OTFTs exhibited the gain of 6.75.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.11a
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• pp.109-115
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• 2007

Instead of existing bar code system, RFID is now the core sensor technique of Ubiquitous computing and it will bring a revolution of corporation's logistics systems. In recent years, RFID becomes the center of government and other related companies and furthermore, its basic and applied techniques and have been established as various international standards. Many major countries announced application cases in various fields and concentrate their effort to make new RFID technologies as well. Recently Korean government announced the basic plan of u-Korea and all-out plan of activation of RFID/USN. SO in this paper, we will discuss two things; the trends of RFID technologies and the printing tag technique, which is needed to spread of RFID item units.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.3
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• pp.70-78
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• 2012

For evaluating the printing suitability of electronic copying papers in the aspect of climate conditions, 12 samples of copying papers being generally used in Korea and worldwide were collected. The copying papers were controlled by various temperature and humidity options in conditioning equipment in order to simulate the specific circumstances of dry, temperate or tropical climate, and the pre-heating system of photocopying machines during printing. As results, some copying papers showed several physical problems, especially in recycled copying papers and a normal paper with original printing faulty. These problems of copying papers were mostly resulted in extremely high moisture circumstance, and in lower levels of tensile strength and tensile stiffness. The moisture contents of copying papers during passing through the pre-heater system of photocopying machine could be rapidly decreased because paper is exposed to high temperature around the pre-heating zone. The copying paper, for example of XR3 sample, containing low moisture contents below 2% had high exfoliating possibility of toner transfer from copying paper.