Patent attributes
The invention relates to methods of producing microfibrillated cellulose (MFC). According to the invention a fibrous pulp suspension is fibrillated mechanically at a consistency of less than 12.5%, dewatered to raise the consistency of the fibrillated suspension to at least 12.5%, and then subjected in the dewatered condition to further fibrillation. Alternatively an initially fibrillated fibrous pulp suspension may be dewatered and fibrillated in the dewatered condition, after which these dewatering and fibrillating steps are repeated one or more times so that pulp consistency is increased for each fibrillation step. The goals of raising the consistency between subsequent fibrillations are energy saving and an increased aspect ratio in MFC. The invention even comprises uses of the MFC product, e.g. as an additive for papermaking furnish or injection molded plastic composites.