Patent ID: 7074299

Claim:
A method of making cellulosic pulp finished stock of a selected brightness utilizing groundwood containing secondary pulp comprising: (a) determining a phloroglucinol color delta for the secondary pulp, by way of (i) taking an initial color reading of a sample, (ii) staining the sample with a phloroglucinol stain, (iii) taking a final color reading of the stained sample, and (iv) calculating the phloroglucinol color delta based on the initial color reading and final color reading; (b) selecting a finished pulp brightness suitable for the secondary pulp of step (a) based on the phloroglucinol color delta of the pulp determined in step (a); (c) optionally blending the secondary pulp with a supplemental cellulosic pulp; (d) optionally de-inking the groundwood containing secondary pulp and supplemental pulp; and (e) bleaching the groundwood containing secondary pulp of step (a) and optionally bleaching the supplemental pulp blended in step (d) to achieve a finished stock having the selected brightness.