Experimental evaluation of water retention for coating color using automatic scanning absorption

Experimental evaluation of water retention for a pigment coating color was performed using automatic scanning absorptometry (ASA) in comparison with the conventional Abo academy gravimetric water retention (AA-GWR) method. It turned out that ASA could evaluate water retention of solution/suspensions for a coating color having various compositions on a real time basis as a base paper absorbs water. The influences that the solid content, pigment type, thickener content, and dispersant content had on water retention were assessed successfully for the ASA method. Overall, good agreements between the results of the ASA and AA-GWR methods were obtained in this study, but there was a small discrepancy in one special case. It appears that this discrepancy can be interpreted on the basis of colloidal phenomena during the coating process, such as cake formation and viscous flow of liquid.