Mechanical pulp fines of poor quality - Characteristics and influence of white water

Fines from white water were compared with fresh TMP fines from the same mil l. The white-water fines gave a low er tensile strength of handsheets and a stronger light absorption. The surface composition (ESCA) and contact angl e indicated more extractives on the surface of these fines. The total extra ctives content was much higher; no other large differences in chemical comp osition or morphology were found. Addition of unbleached white water to fre sh fines had no effect on the tensile strength, whereas addition of white w ater subjected to hydrogen peroxide bleaching gave an immediate decrease.