Two new laboratory methods for studying the process of ink separation
from cellulose fibers are presented. A modified spinning drop tensiome
ter can measure the interfacial tension between deinking surfactants a
nd model inks within the time frame of the pulping stage. One-dimensio
nal H-1 nuclear magnetic resonance imaging can measure the rate at whi
ch model inks separate from cellulose fibers. Both methods show promis
e as rapid screening tools for predicting the deinking effectiveness o
f deinking surfactants.