The present disclosure relates to producing paper or
paperboard having improved stiffness and strength, compared to the conventional
paperboard at the same basis weight. It also discloses a method of wood pulping having a significantly increased yield and providing
fiber pulps with enhanced properties such as strength and stiffness. Wood chips are chemically pulped to a high
kappa number, providing a rejects component and an accepts component. The rejects component is subjected to a substantially mechanical pulping process, optionally in a presence of bleaching agent, prior to blending back into the accepts component. The resulting
fiber blend is washed, optionally bleached, and subjected to a
papermaking process to provide paper or
paperboard with enhanced strength and stiffness at low basis weight.