1973 年 27 巻 3 号 p. 131-140
Beech, oak, lauan, and pine woods were made into chips of 1.5-3.0 mm in thickness, and the chips were cooked with NaOH and O2 using a rotating autoclave under the conditions shown in Table 2. Pine and lauan chips consumed more O2 than did beech and oak chips. The partially-delignified chips were then defiberized mechanically to make the oxygen-alkali method semichemical pulp (OSCP). The chips were possible to be defiberized mechanically without breaking of fibers.
The yield, Kappa number, brightness, and C. I. E color scales of OSCP were compared with those of the neutral sulfite method semichemical pulp (NSSCP) and the kraft method semichemical pulp (cf. Table 3, 4, and 5). OSCP was high in yield and tan or yellowish white colored.
The test sheets were made of OSCP and NSSCP, and studied for their breaking length, burst factor, and tear factor. OSCP were comparable to NSSCP on the strength of the sheet (cf. Table 6).
The test fibreboards were made of OSCP, NSSCP, and refiner ground wood pulp, and studied for their specific gravity and bending strength. On the bending strength, the fibreboard made of OSCP was almost on a level with the fibreboard made of NSSCP and was on much higher level than that made of refiner ground wood pulp (cf. Table 7).