전자인쇄용 트렌치 패턴 형성을 위한 와이핑 그라비어 인쇄 방법에 관한 연구

Abstract

Gravure printing is one of the most promising high-speed, roll-to-roll technique for printed electronics. And the printing of electronic parts is undergoing rapid changes from Screen to Gravure method in image information technology and applications. In our research, we demonstrated that high viscous silver ink with trench pattern is suitable for printing fine lines by studying specific printing parameters. This paper proposes a high viscous silver ink with trench pattern suitable for printing fine lines. To realize the fine lines, we first manufactured a new nanoparticle silver paste ink to improve the printing quality, vis-a-vis smooth surface and high conductive lines. Then a new ink filling process was developed to fill the trench pattern with the high viscous ink. The wiping and doctoring method was applied to obtain uniform and narrow lines by controlling the printing conditions. To resolve the difficulty in transferring the high-viscous conductive ink, a new wiping gravure device was developed by placing the wiping device prior to the doctoring process. Also the feasibility of applying the wiping device to Gravure printing is evaluated using the Gravure printing testing machine, and the functions of the printing mechanism were confirmed through computer simulations. We tried to maximize high viscous printing by using the groove pattern within the edge tolerance of trench pattern reproduction instead of common gravure cells. In order to realize the trench line on polyamide film, a new nanoparticle silver paste ink was developed and etched into a fixed depth of 20μm. Then, a new ink filling process was developed to fill the grooves with high viscous ink. Finally, high conductive lines with high resolution were formed based on the optimization that resulted from each printing process. The wiping cylinder was make by water-soluble polymer like the one used in the intaglio method, and it is one of the most suitable in high molecular substance. We used the PVA whose hardness is adjustable as a wiping cylinder. It is expected that using of the wiping gravure printing method could make it possible to print trench patterns with the conductive ink for electronic printing. In this paper seven different mechanisms of wiping gravure system are proposed. A suitable manufacturing facility for producing wiping gravure mechanisms may be selected after a thorough discussion of detailed design and consideration of atmospheric pollution issues. The printed fine line patterns are especially used in the manufacturing of TFTs requiring high conductivity and large-scale integrated circuits. At present, the printing of electronic parts is apparently undergoing a gradual change from Screen to Gravure method, and thus this study is expected to contribute to the development of industries in image information technology and application.