PREPARATION OF MECHANICAL PULPS FOR TESTING

This practice describes a procedure for the preparation of mechanical pulps prior to physical testing.

It is for use with pressure groundwood, refiner mechanical, chemimechanical, thermomechanical, and chemithermomechanical pulps. It may also be used on any pulp sample taken downstream of the refiners (i.e., screens, cleaners, reject refiners, etc.). The purpose of this practice is to remove latency (curl) from pulp fibers.

Hot disintegration of pulps containing lignin may lead to significant loss of brightness. Since brightness is not significantly changed by the presence of latency in the pulp, this procedure is not recommended for pulps that will be formed into brightness measuring sheets.