Effect of Recycling Number on the Fluorescence Reduction of Fluorescent Whitening Agents in White Wastepapers
Fig. 5. Fluorescence index (left) and fluorescence reduction (right) for the paper containing D-FWA as a function of the number of recycling rounds.
Fig. 6. Fluorescence index (left) and fluorescence reduction (right) for the paper surface-sized with T-FWA as a function of the number of recycling rounds.
Fig. 7. Fluorescence index (left) and fluorescence reduction (right) for the paper surface-sized with H-FWA as a function of the number of recycling rounds.
recycling processes increased to five, the T-FWA and H-FWA reduction logarithmically increased together. However, the maximum fluorescence re-
duction varied according to the type of FWA used. The fluorescence reduction of T-FWA showed al- most 50% when the paper was surface-sized with
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펄프·종이기술 51(2) 2019
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