紫外光对荧光增白剂衰减的影响研究

为了进一步增加纸张的亮度和白度，许多商用纸张都添加了荧光增白剂。荧光增白剂的效力会随在光源下暴露时间的增加而衰减，特别是在加速衰减的测试中和暴露在特殊视觉环境下会产生明显的变化。本实验使用单色仪将含有荧光增白剂的印刷用纸暴露在单波段350nm光源下，研究纸张反射率的变化。实验结果显示，荧光增白剂效力的衰减非常微弱，且快速衰减过程主要集中在第1h内，造成衰减的区域主要是380～420nm。实验总共持续了7．5h，造成纸张色差变化（CIELAB 1976△E^＊ab）约为0．5。

Effect of Ultravidet Radiation on Attenllation of Fluorescent Whitening Agents

Fluorescent whitening agents are widely used to increase the brightness and whiteness of printing paper. The fluorescence of fluorescent whitening agents is known to fall as a result of exposure to light, and the magnitude of the change has been documented in both accelerated attenllation tests and exposure under more typical viewing conditions. In this paper, printing paper with fluorescent whitening agents was exposed under narrow-band radiation at 350 nm, using a monochromator. The change of spectral reflectance was found. The result shows that the attenllation is small, with a relatively rapid initial change during the first hour in the 380-420 nm regions. It also can be seen that CIELAB 1976 △ E＊ab during 7.5 hours exposure is approximate 0.5