Specific perimeter of fibre flocs - a criterion of paper formation

The quality of paper formation is usually evaluated in terms of the coefficient of variation (COV) or the specific perimeter (SP). The COV of the mass distribution in a sheet of paper is estimated by measuring the intensity of transmitted light. In this study, we have shown that the COV was significantly influenced by the opacity, the light-scattering coefficient and the density of the paper. The SP, which is a measure of the floc size in paper, was found to be independent of changes in the paper opacity, but dependent on the change in sheet density.