소수성 마이크로 패턴을 갖는 Stripe 코팅용 슬롯 다이 헤드 구조 최적화

Structure Optimization of a Slot-Die Head with a Hydrophobic Micro-Patterns for Stripe Coatings

  • 유수호 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 이진영 (한국기술교육대학교 창의융합공학협동과정) ;
  • 박종운 (한국기술교육대학교 전기.전자.통신공학부)
  • Yoo, Su-Ho (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Lee, Jin-Young (Interdisciplinary Program in Creative Engineering) ;
  • Park, Jong-Woon (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education)
  • 투고 : 2019.05.10
  • 심사 : 2019.06.18
  • 발행 : 2019.06.30

초록

In the presence of $\mu-tip$ for narrow stripe coating, there appears lateral capillary flow along the hydrophilic head lip because the $\mu-tip$ has some resistance to flow. It was known to be suppressed by increasing the contact angle of the head lip. In this paper, we have demonstrated by computational fluid dynamics(CFD) simulations that it can also be suppressed by the formation of micro-patterns on the shim and meniscus guide embedded into the slot-die head. To optimize the micro-patterned structure, we have performed simulations by varying the groove width, depth, and clearance. In the absence of micro-patterns, it is shown by experiment and simulation that the solution spreads to a distance of $1,300{\mu}m$ from the ${\mu}-tip$. In the presence of micro-patterns with the groove width and clearance of $50{\mu}m$, the distance the solution spreads is reduced to $260{\mu}m$. However, no further suppression in the capillary flow is observed with micro-patterns with the groove width of $40{\mu}m$ or less. It is also observed that the capillary flow is not affected by the groove depth if it is larger than $10{\mu}m$. We have shown that the distance the solution spreads can be reduced further to $204{\mu}m$ by coating a hydrophobic material (contact angle of $104^{\circ}$) on the surface of micro-patterns having the groove width and clearance of $50{\mu}m$.

키워드

참고문헌

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