Effect of surfactant addition on curtain coating color properties and curtain stability

계면활성제 첨가가 커튼 코팅용 도공액의 물성과 커튼 안정성에 미치는 영향

  • Oh, Kyu-Deok (Dept. of Forest Sciences, Seoul National University) ;
  • Kim, Chae-Hoon (Dept. of Forest Sciences, Seoul National University) ;
  • Youn, Hye-Jung (Dept. of Forest Sciences, Seoul National University) ;
  • Lee, Hak-Lae (Dept. of Forest Sciences, Seoul National University)
  • 오규덕 (서울대학교 농업생명과학대학 산림과학부) ;
  • 김채훈 (서울대학교 농업생명과학대학 산림과학부) ;
  • 윤혜정 (서울대학교 농업생명과학대학 산림과학부) ;
  • 이학래 (서울대학교 농업생명과학대학 산림과학부)
  • Received : 2011.12.05
  • Accepted : 2011.12.27
  • Published : 2011.12.30

Abstract

Curtain coating has been considered as the best coating technology because it is a coating technology that forms contour coating layer with better coverage. To increase the curtain stability surfactants are being used. In this study, the effect of a surfactant on the stability of curtain coating colors was examined by evaluating dynamic surface tension with a bubble surface tensiometer. Di-2-ethylhexyl sodium sulfosuccinate was used as a surfactant since it showed low dynamic surface tension at low surface age. And we evaluated the influence of surfactant on coating color properties including surface tension, viscosity and curtain stability. The surface tension of coating color was decreased when surfactant addition was increased up to 0.5 pph, but it was leveled off at 0.3 pph of surfactant addition. With the increase of surfactant addition rate, viscosity of coating color were increased. Micelles formed by surfactant contributed to the increase of the viscosity. Curtain stability was improved with the addition of surfactant until it reached up to 0.5 pph. Excessive addition of surfactant (> 0.5 pph) didn't improve curtain stability. This was attributed to Marangoni effect(self-healing) and decreasing of curtain thickness.

Keywords

References

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