[ Article ]

Journal of the Korean Society of Manufacturing Technology Engineers - Vol. 32, No. 5, pp.267-273

ISSN: 2508-5107 (Online)

Print publication date 15 Oct 2023

Received 10 Sep 2023 Revised 26 Sep 2023 Accepted 05 Oct 2023

DOI: https://doi.org/10.7735/ksmte.2023.32.5.267

가변형 슬롯 다이 코팅의 균일도 확보를 위한 토출 유량 정밀 측정 및 제어

배예은^a ; 윤경택^a ; 이현호^a ; 이문구^a ; 김현정^a ; 최영만^a^{, *}

Precision Measurement and Control of Flow Rate for Coating Uniformity in Variable Slot Die Coating

Yeeun Bae^a ; Kyung-Taek Yoon^a ; Hyun-Ho Lee^a ; Moongu Lee^a ; Hyun-Jung Kim^a ; Young-Man Choi^a^{, *}

aDepartment of Mechanical Engineering, Ajou University

Correspondence to: ^*Tel.: +82-31-219-2342 E-mail address: ymanchoi@ajou.ac.kr (Young-Man Choi).

Abstract

Slot die coating is a pre-metered coating process commonly used for manufacturing thin and wide films with high production speed and good uniformity. Recently, there has been an increasing demand for variable-width coating by changing the slot width. In this case, the discharged flow rate per unit width must be continuous for optimal uniformity thickness. This study assesses the flow rate from the variable width slot die nozzle by adapting a gravimetric method using a precision weighing balance. Changing slot width alters internal flow dynamics. Therefore, through the fluid simulation, we gauged any flow rate change caused by the hydrodynamic force from the width change. For uniform coating thickness, we controlled the pump with the feedforward method from the baseline obtained by the simulation. Experimental results demonstrate that the flow rate error was enhanced by 81% and 14% for opening and closing slot cases, respectively.

Keywords:

Slot die coating, Coating uniformity, Variable width, Gravimetric method, Flow meter

Acknowledgments

This work was supported by Technology Innovation Program, (No. 20014812), funded by the Ministry of Trade, Industry & Energy (MOTIE, Republic of Korea).

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Yeeun Bae

M.S. Candidate in the Department of Mechanical Engineering, Ajou University. Her research interest is High-precision Machine and Force Sensors.

E-mail: bae625276@ajou.ac.kr

Kyung-Taek Yoon

Ph.D. Candidate in the Department of Mechanical Engineering, Ajou University. His research interest is Novel Instrumentation Systems, Actuator Design, and Biomechanical Wearable Devices.

E-mail: majesty17@ajou.ac.kr

Hyun-Ho Lee

Ph.D. Candidate in the Department of Mechanical Engineering, Ajou University. His research interest is High-precision Mechatronics Systems, Actuator Design, and Biomechanical Devices.

E-mail: lho3692@ajou.ac.kr

Moongu Lee

Professor in the Department of Mechanical Engineering, Ajou University. His research interest is Design and Control of Precision System Control.

E-mail: moongulee@ajou.ac.kr

Hyun-Jung Kim

Professor in the Department of Mechanical Engineering, Ajou University. His research interest is Photothermal Imaging, Thermal Property Measurement, Heat Transfer, Visualization of Heat, Mass Transfer, Photothermal Therapy and Secondary Battery.

E-mail: hyunkim@ajou.ac.kr

Young-Man Choi

Associate Professor in the Department of Mechanical Engineering, Ajou University. His research interest is High-precision Machines, Mass Metrology and Wearable Mechatronics.

E-mail: ymanchoi@ajou.ac.kr