Role of contact angle in the octadecanol agglomeration of electrostatic toners, Journal of Pulp and Paper Science, March 2001, Vol. 27(3)

J. Zheng, R. A. Venditti, H. G. Olf

A liquid bridge is believed to be a mechanism acting in the chemical agglomeration of contaminants in wastepaper pulps. According to that mechanism, interfacial tension (gamma) between the agglomerating liquid and the aqueous medium and contact angle (theta) of the agglomerating liquid on the contaminant surface are important parameters that affect the attractive forces in an agglomerate and therefore affect the agglomeration performance. In this project, static contact angles of interest were measured under the same conditions as agglomeration experiments and the contact angle values and agglomeration efficiencies were compared. Contact angle values were shown to correlate with agglomeration efficiency with respect to the presence of starch and the type of agglomerating liquid for a given toner.