Wiggins K, Holness J A
The Forensic Science Service, London Laboratory, 109 Lambeth Road, London SE1 7LP, England.
Sci Justice. 2005 Apr-Jun;45(2):93-6. doi: 10.1016/S1355-0306(05)71634-8.
Four sets of acrylic fibre samples were obtained from a company that dyes fabrics for the fashion industry. Between seven and ten different batches of fibres constituted each set. Comparison microscopy, visible and UV range microspectrophotometry and thin layer chromatography (TLC) were used to compare the dyes on each batch of fibres within the sets. Only one of the four sets exhibited variation within the batches. The differences were seen when both microscopical and analytical techniques were used. In addition, two further sets of samples had been obtained from a company that produces carpets for the car industry. The first set consisted of 26 batches of acid dyed orange nylon fibres. The second consisted of 21 batches of acid dyed mustard coloured nylon and direct dyed brown viscose fibres blended together. When the first set was viewed under UV light one batch had more pale orange fibres present and they fluoresced more brightly than the other fibres. This could be due to the blending with a different dye batch of fibre or due to poor dye uptake--the latter being more likely. When tested using visible and UV range microspectrophotometry and TLC, further dye batch variation was not detected. The second set was examined after separating the nylon and viscose fibres from each other. The nylon fibres were indistinguishable when a range of microscopical and analytical techniques were employed; however, the viscose fibres showed dye batch variation when TLC was used.
从一家为时尚产业染织物的公司获取了四组腈纶纤维样品。每组由七到十个不同批次的纤维组成。使用比较显微镜、可见光和紫外光范围的显微分光光度法以及薄层色谱法（TLC）来比较每组内各批次纤维上的染料。四组中只有一组在批次间呈现出差异。当同时使用显微镜和分析技术时可以看到这些差异。此外，还从一家为汽车行业生产地毯的公司获取了另外两组样品。第一组由26批次酸性染色的橙色尼龙纤维组成。第二组由21批次酸性染色的芥末色尼龙纤维和直接染色的棕色粘胶纤维混合而成。当在紫外光下观察第一组时，有一批次存在更多浅橙色纤维，并且它们发出的荧光比其他纤维更亮。这可能是由于与不同染料批次的纤维混合，或者是由于染色效果不佳——后者可能性更大。当使用可见光和紫外光范围的显微分光光度法以及TLC进行测试时，未检测到进一步的染料批次差异。在将第二组中的尼龙纤维和粘胶纤维彼此分离后进行了检查。当采用一系列显微镜和分析技术时，尼龙纤维难以区分；然而，当使用TLC时，粘胶纤维显示出染料批次差异。
