High Shear Anilox Cell Discharge Mechanics in Flexographic Aqueous Dispersion Application
Liquid release from anilox cells under high shear depends on dynamic viscosity below forty centipoise and cell depth ratios under thirty percent.
Depth to Opening Ratio
Volume Geometry
Geometric proportion between the depth of an engraved cell and its surface width dictates the efficiency of fluid transfer in gravure printing. Calculating the depth to opening ratio helps engravers predict how much ink will remain trapped in the cell after the substrate passes. A typical value sits between zero point one and zero point four for most packaging applications.
This figure describes the steepness of the cell walls and the shape of the internal pocket.
Release Mechanic
Surface tension and liquid viscosity prevent a cell from emptying completely when the ratio is too high. If the depth to opening ratio exceeds a certain threshold, the ink stays pinned to the bottom by capillary forces. This leads to starving the print and causing a loss of colour density.
Ink Transfer
High speed presses require a balanced cell shape to maintain consistent coverage across various web speeds. A shallow depth to opening ratio allows the ink to move easily onto the paper or film surface. When the ratio is too low, the cells become too shallow to hold a meaningful volume of pigment.
Optimal settings vary depending on whether the job uses solvent or water based systems. Engravers adjust the diamond stylus angle to hit the target ratio for specific coat weights.