POSSIBLE IMPROVEMENTS IN TEARING STRENGTH OF CLUSTER PINE KRAFT PULP

The teating strength of kraft pulping of Pinus pinaster can be improve d by homogenisation of transfer kinetics between earlywood and latewoo d. Chip impregnation by alkaline liquor, chip destructuration or modif ications of cooling conditions with very slow temperature growing are easy and simple solutions that allow to improve tear index about 25 to 40 %. But tear index improvements are lost after beating. Two-stage p ulpings with weak alkalies give unbeaten pulp with exceptional lear in dex conserved after healing.