Paper Pulp

a mixture of fibrous materials prepared by a special method in water supplemented with fillers, dyes, and sizing substances, for the preparation of paper and cardboard. Sheets of paper are made from this mixture by pouring and drying it in a paper machine.

Paper pulp is obtained by chemical and mechanical treatment of fibrous materials. Mechanical treatment of the fibrous materials is carried out by means of grinding, during which separation, fibrilization, and shortening of fibers takes place. Depending on the type of grinding, it is possible to produce either heavy paper pulp when the fibrous (cellulose) material is broken down into fibrils or lean paper pulp when the fibers are only shortened without being broken down significantly. By varying the amounts of shortening and fibrilizing of fibers, it is possible to obtain paper pulp with a varying type of grinding, which permits the manufacture of paper with the desired properties.