화학공학소재연구정보센터
International Polymer Processing, Vol.27, No.1, 128-137, 2012
Three-Dimensional Observation on the Liquid Emptying Process from a Scaled-up Gravure Cell
The performance of gravure coating is strongly dependent on the break-up of the liquid bridge connecting the surfaces of the moving roller and gravure cell. The mechanism of the movement and subsequent break-up of the liquid bridge were studied experimentally using a three-dimensional flow visualization technique. Three stages of liquid motion were observed, and two characteristic lengths were defined to quantify the liquid pick-out and bridge break-up. The pick-out and break-up mechanisms were influenced by the capillary number, coating gap and the geometry of the gravure cell. A universal correlation between the pick-out and these variables was found.