IMPROVING METHOD FOR WHITENESS AND RESISTANCE TO LIGHT OF PAPERS

摘要

PURPOSE:To improve whiteness and resistance to light of paper by making papers made of cellulosic fiber coexistent with fluorescent dye and PVA-based polymer, etc. CONSTITUTION:Papers mainly composed of cellulosic fiber is coexisted with fluorescent dye (preferably stilbene-based direct dye) and PVA-based polymer of =80% saponification value and/or polyvinyl pyrrolidone-based polymer composed of =90% vinyl pyrrolidone group to improve whiteness and resistance to light of papers. Besides, 0.5-10vol.% water-soluble polymer as 1wt.% aqueous solution and 0.01-0.1wt.% aqueous solution of fluorescent dye are preferably used.