A new analysis of filler effects on paper strength

Information about the disruption of fibre/fibre bonds by fillers was derived from measurements of the peel force required to delaminate two-ply handsheets with a sparse layer of fillers between the plies. The smallest filler particles have the greatest negative effect on delamination strength. A surprising finding was that polystyrene spheres had little effect on strength. Electron microscopic evidence suggests that the particles rolled away …