CHARACTERISTICS OF PAPER OBTAINED FROM TROPICAL SOFTWOOD AND HARDWOODPULPS

In this work, handsheets of basis weight 75 g/m(2) were made. at varyi ng compositions of softwood and hardwood pulps. The Pinus caribaea var . hondurensis pulp was beaten to a degree of freeness of 30-32 degrees SR, whereas the hardwood pulp - Gmelina arborea, was beaten to 40-42 degrees SR. Initially, handsheets were made from the bleached pulps wi thout any additive and subsequently, handsheets of 6-8% ash content we re prepared with the addition of kaolin. Finally, sized handsheets of ash content 6-8% were also made (2% rosin size, 4% alum). It has been established that the addition of hardwood pulp to softwood pulp up to 50% by volume or weight does not reduce the main mechanical properties of the paper. The work has also shown that the addition of kaolin and aluminium sulphate and the addition of rosin size correspondingly red uces the mechanical properties of paper, especially folding endurance and tear index.