Rheoviscometry of offset inks and their emulsions with water

A stress-controlled rheometer with cone and plate geometry was used to stud y the rheological properties of four sets of process offset inks and their emulsions with low water content. All systems have shown typical pseudoplas tic shear-thinning behaviour. Because of some measuring problems concerning a remounting of inks from measuring gap, the flow curve was properly segme nted and the optimal measuring interval DeltaD(opt) was defined. The Ostwal d flow model was chosen as the best from three applied mathematical models. Finally, the quantitative how parameters were calculated and discussed in connection with ink press performance.