高白度螢光增白紙之配方

Preparation of Highly Brightened Papers

白紙中添加可吸收紫外光反射成帶藍色強烈可視光及少量藍色染料中和白漿之微黃色，使紙視之益白。某紙廠委妥本試驗室研製可比美歐進口高視白度之白紙配方。試驗結果顯示紙漿油離度對視白度影響不大；利用含強紫外光之氙光源測色儀找出完全對色之白紙配方為利用高白度進口亞硫酸鹽紙漿（白度大於90% ISO），添加不吸收紫外光之高白度碳酸鈣填料，高螢光增白效果之螢光染料及帶藍色提色劑所抄出之鹼性手抄紙之顏色值：視白度146.27%，CIEL*a*b*94.14/2.25/13.43足堪比美進口之高視白度紙之顏色值：視白度147.17%，CIEL*a*b*94.26/1.95/-13.58。 Paper dyed with fluorescent agent will convert ultraviolet light to a longer wavelength and thereby produce additional white light and increase the apparent brightness or whiteness. To achieve a higher whiteness of paper, many papermakers include a fluorescent whitening agent (FWA) or shading dyestuff in the paper. In this study, we attempt to prepare a highly brightened alkaline CaCO3 filled paper in which color will be comparable to imported one at a request of Taiwan papermaker. It was found out that whiteness of brightened paper was not markedly affected by the varying freeness of bleached pulps. A matched highly brightened hand sheet (whiteness 146.27%, CIE L*a*b* 94.14/2.25/- 13.43) could be prepared by selecting certain FWAs, bluish shading dyestuffs, high brightness CaCO3 and bleached sulfite to pulp (brightness>90% ISO) and NaBH4 treated bleached pulp, when compared to the color (147.17%, 94.26/1.95/-13.58 standard) of imported brightened printing paper.

Paper dyed with fluorescent agent will convert ultraviolet light to a longer wavelength and thereby produce additional white light and increase the apparent brightness or whiteness. To achieve a higher whiteness of paper, many papermakers include a fluorescent whitening agent (FWA) or shading dyestuff in the paper. In this study, we attempt to prepare a highly brightened alkaline CaCO3 filled paper in which color will be comparable to imported one at a request of Taiwan papermaker. It was found out that whiteness of brightened paper was not markedly affected by the varying freeness of bleached pulps. A matched highly brightened hand sheet (whiteness 146.27%, CIE L*a*b* 94.14/2.25/- 13.43) could be prepared by selecting certain FWAs, bluish shading dyestuffs, high brightness CaCO3 and bleached sulfite to pulp (brightness>90% ISO) and NaBH4 treated bleached pulp, when compared to the color (147.17%, 94.26/1.95/-13.58 standard) of imported brightened printing paper.