Wang S Q, Kopf A W, Marx J, Bogdan A, Polsky D, Bart R S
Ronald O. Perelman Department of Dermatology, New York University School of Medicine, New York, NY, USA.
J Am Acad Dermatol. 2001 May;44(5):767-74. doi: 10.1067/mjd.2001.112384.
The public has long been instructed to wear protective clothing against ultraviolet (UV) damage.
Our purpose was to determine the UV protection factor (UPF) of two cotton fabrics used in the manufacture of summer T-shirts and to explore methods that could improve the UPF of these fabrics.
Each of the two types of white cotton fabrics (cotton T-shirt and mercerized cotton print cloth) used in this study was divided into 4 treatment groups: (1) water-only (machine washed with water), (2) detergent-only (washed with detergent), (3) detergent-UV absorber (washed with detergent and a UV absorber), and (4) dyes (dyed fabrics). Ultraviolet transmission through the fabrics was measured with a spectrophotometer before and after laundry and dyeing treatments. Based on UV transmission through these fabrics, the UPF values were calculated.
Before any treatments, the mean UPFs were 4.94 for the T-shirt fabric and 3.13 for the print cloth. There was greater UVA (320-400 nm) than UVB (280-320 nm) transmission through these fabrics. After 5 washings with water alone and with detergent alone, UPF increased by 51% and 17%, respectively, for the cotton T-shirt fabric. Washing the T-shirt fabrics with detergent plus the UV-absorbing agent increased the UPF by 407% after 5 treatments. Dyeing the fabric blue or yellow increased the UPF by 544% and 212%, respectively. Similar changes in UPFs were observed for the print cloth fabric.
The two cotton fabrics used in this study offered limited protection against UV radiation as determined by spectrophotometric analysis. Laundering with detergent and water improves UPF slightly by causing fabric shrinkage. Dyeing fabrics or adding a UV-absorbing agent during laundering substantially reduces UV transmission and increases UPF. More UVA is transmitted through the fabrics than UVB.
长期以来，公众一直被建议穿着防护服以防紫外线（UV）伤害。
我们的目的是测定用于制作夏季T恤的两种棉织物的紫外线防护系数（UPF），并探索可提高这些织物UPF的方法。
本研究中使用的两种白色棉织物（棉质T恤和丝光印花布）每种都分为4个处理组：（1）仅用水（用水机洗），（2）仅用洗涤剂（用洗涤剂洗涤），（3）洗涤剂 - 紫外线吸收剂（用洗涤剂和紫外线吸收剂洗涤），以及（4）染色（对织物染色）。在洗涤和染色处理前后，用分光光度计测量织物的紫外线透过率。根据这些织物的紫外线透过率计算UPF值。
在任何处理之前，T恤织物的平均UPF为4.94，印花布的平均UPF为3.13。通过这些织物的UVA（320 - 400nm）透过率高于UVB（280 - 320nm）。棉质T恤织物单独用水和单独用洗涤剂洗涤5次后，UPF分别增加了51％和17％。用洗涤剂加紫外线吸收剂洗涤T恤织物5次后，UPF增加了407％。将织物染成蓝色或黄色后，UPF分别增加了544％和212％。印花布织物也观察到类似的UPF变化。
通过分光光度分析确定，本研究中使用的两种棉织物对紫外线辐射的防护作用有限。用洗涤剂和水洗涤会导致织物收缩，从而使UPF略有提高。在洗涤过程中对织物染色或添加紫外线吸收剂可大幅降低紫外线透过率并提高UPF。透过织物的UVA比UVB更多。
