Question

The kappa number of bleachable softwood pulps is _______

(a) 10-20

(b) 20-30

(c) 30-40

(d) 40-50

I had been asked this question in class test.

Asked question is from Chemical Pulping & Semichemical Pulp topic in section Paper and Paper Based Packaging Materials of Food Packaging Technology

Answer 1

The correct choice is (c) 30-40

To explain I would say: The kappa number of bleachable softwood pulps is 30–40. The pulp and paper industry uses the “kappa number” to express the lignin content of a pulp, a high kappa number indicating high lignin content.