Thermomechanical pulp (TMP) fibres of higher (as slabwood) and lower (
thinnings) coarseness behave differently in their screening response a
nd when selectively refined. Greater long fibre removal efficiencies a
re achieved for the thinnings pulps, as the result of their lower long
fibre content. Thinnings, but not slabwood, long fibre differs in its
energy and handsheet property freeness relationships, between differe
nt mainline energy applications and screen reject rates.