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A study on the curing characteristics of multi-concentrating UV-LED Curable Coating

다중 집광성 UV-LED 경화형 코팅의 경화특성에 관한 연구

  • Jung, Chan-Gwon (ICT Fusion Green Energy Research Institute, Wonkwang University) ;
  • Kim, Beom-Su (SongBaek E&S Corporation) ;
  • Park, Dae-Hee (Department of Information Communication, Wonkwang University)
  • 정찬권 (원광대학교 ICT융합 그린에너지 연구원) ;
  • 김범수 (송백이엔에스) ;
  • 박대희 (원광대학교 정보통신공학과)
  • Received : 2018.07.20
  • Accepted : 2018.10.05
  • Published : 2018.10.31

Abstract

We investigated the curing properties of cured coatings for a multi-focal UV-LED. The coatings are for LEDs that operate at multiple UV wavelengths, unlike conventional single-wavelength UV-LEDs. Using UV-LED light sources with wavelengths of 365, 395, 420, and 450 nm, we analyzed the optical characteristics such as the direction of light flux and light source. We also analyzed the curing characteristics at each UV-LED wavelength to optimize the LED for composite wavelengths. The curing performance state was predicted through computer simulation for when the multiple wavelengths of UV light sources are superimposed, and then actual LEDs were designed and fabricated. To improve the internal high-speed curing, a multi-spot module was fabricated, in which each LED is condensed, and multiple wavelengths are synthesized and condensed at the same position. The adhesive strength, surface hardness, and internal hardness of the curing agent were tested by varying the wavelength combination conditions. The surface hardening and internal hardening were compared and analyzed using a hardness tester and FT-IR analyzer. As a result, the characteristics of the surface and internal hardness were improved by a multi-spot method in which four wavelengths were overlapped in a UV-LED rather than a single wavelength.

Keywords

UV-LED;curing;multi-spot;adhesive strength;hardness

Acknowledgement

Supported by : 원광대학교

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