Patent ID: 8262850

Claim:
A method for modulating the morphology of softwood fibers comprising the steps of: subjecting pulp containing softwood fibers to a solution containing ferrous (II) or ferric (III) metal ions at a concentration of from 0.002% to about 0.1% by weight based on pulp and a peroxide at a pH between about 2 and about 7 for a time of from about 10 minutes to about 10 hours at a temperature from about 40 to 120° C. to cause ferrous (II) or ferric (III) metal ion catalyzed oxidative degradation of cellulose of such peroxide treated softwood fibers, and directly refining the peroxide treated and oxidatively degraded fibers to form refined paper making fibers which exhibit a substantially shorter fiber length and distribution and enhanced fiber collapsibility compared to the unrefined paper making fibers, wherein said method reduces fiber suspension viscosity after said refining step.