Patent ID: 9546452
Date: 2017-01-17
CPC Classifications: D21H

Claim:
1. A method of producing a paper board comprising: disintegrating and beating fibers from a pulp raw material containing waste paper as a main raw material in water to obtain pulp slurry; adding an additive containing a paper strength additive to the obtained pulp slurry to obtain a prepared pulp raw material; and making the obtained prepared pulp raw material into a paper board, wherein the paper board is produced by adding to the pulp slurry from a pulper to a completion chest to reduce an amount of the paper strength additive added while obtaining the prepared pulp raw material; wherein the pulp slurry has a pulp concentration of 3 to 5%; and wherein the component (a) has a concentration of 1000 to 9000 mg/L as an effective chlorine concentration; the component (b) has a concentration of 1000 to 9000 mg/L; the component (a) and the component (b) in which a molar ratio of effective chlorine in the component (a) and nitrogen in the component (b) is 1:1 to 1:2 are added at 1 to 40 mg/L as converted in terms of effective chlorine concentration with respect to the pulp slurry; and said additives are added at any point between the pulper and the completion chest.