Screen Printing Conductive Ink Transfer Mechanism and Simulation Research

doi:10.3901/JME.2021.05.231

Abstract

Abstract: In order to clearly and intuitively understand the mechanism of the ink filling mechanism and the screen rebound mechanism. According to the screen-printing ink transfer process, the theoretical analysis model is established. The fluid dynamics is used to analyze the function relationship between the ink outlet speed and pressure change during the ink filling process. The elastohydrodynamic lubrication is used to analyze the influence change between the dynamic pressure of the wedge zone and the rebound force generated by the ink; and Fluent is used to verify the analysis results. The theoretical results show that when the dynamic pressure in the wedge area is 8×10⁵Pa, the resilience of conductive ink at both ends of the mesh is significantly greater than that at the middle position, and the resilience at the position of 20- 30 μm does not change basically. The simulation results show that when scraping with the increase of knife speed, the ink outlet speed increases, but the pressure change shows a decreasing trend. This proves that the scraper speed of screen printing cannot be too large or too small, and there is an optimal speed range, about 40-65 m/s. Under different dynamic pressure of wedge area, the two ends of ink resilience at the mesh are greater than the middle position, and there is no change in the position of 20-30 μm. The maximum ink drop on the substrate occurs in the wedge area, and the dynamic pressure is 7×10⁵-9×10⁵Pa, it accounts for 95.6% of the mesh volume, which is about 0.189 3 mm³. In order to ensure enough ink drop on the substrate, the dynamic pressure of wedge area can be increased to improve the printing quality.

Key words: conductive ink, drop volume, transfer mechanism, screen printing, dynamic pressure in wedge region

CLC Number:

TS801

LIU Shipu, LI Yan, TIAN Ye, YUAN Yingcai. Screen Printing Conductive Ink Transfer Mechanism and Simulation Research[J]. Journal of Mechanical Engineering, 2021, 57(5): 231-241.

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