The authors will discuss the use of a new proprietary polymer chemistry which enhances retention of fillers, optical brighteners (OBAs) and fluorescent whiteners (FWAs) to reduce chemical costs, meet grade specifications quickly, improve sheet strength and print properties and increase paper machine efficiency. Industry sheet brightness targets have increased significantly now commonly including TAPPI brightness of 92, 96 and 98. Producers of printing and writing papers continuously seek better methods of improving their sheet brightness by using higher levels of bleaching, brighter fillers, higher filler content and optical brighteners and fluorescent whiteners fed in the wet end, size press or both. There are significant costs associated with the use of these methods related to chemical costs and the impact on paper machine runnability. With proper wet end management and the use of new proprietary coagulant polymers significant improvements are being made adding synergy to additives used, increasing functional OBA/FWA chemicals and filler retention and also often improving drainage and dewatering and sheet properties. At least two mill applications of the new coagulant will be discussed providing examples where it replaced typical chemistries that actually defeat or dull OBA/FWA additives' performance. It will discuss the use of higher filler levels made possible with fewer sheet defects, reduced dusting and linting and improved paper machine runnability.
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