餐巾纸标准规定,白度不能超过90％以上。一般来说,超过这一标准的多数是在制造过程中加入了对人体有害的荧光增白剂。所以应选购本色的。 本色的概念是:纸浆纤维总是略呈黄色至灰白色,即使经过漂白处理,也依然带黄光,这是由于纸纤维中所含大量倾向于吸收波长在4000—5000A的紫色和 Napkins standards, whiteness can not exceed 90%. In general, the majority exceeding this standard is the incorporation of fluorescent agents that are harmful to the human body during the manufacturing process. So should buy the true colors. The true concept is: pulp fibers are always slightly yellow to gray, even after bleaching, but also with yellow light, which is due to the large number of fibers contained in paper tend to absorb the wavelength 4000-5000A purple and