Study on Methods for Removing Extractable aldehyde from Leathers and Furs.

本研究旨在建立制革脱醛和脱醛的方法。主要研究结果如下：(1)用不同pH和浓度的反照剂处理胶原纤维和兔毛，在不同的时间和温度条件下测定样品中乙醛的萃取量。结果表明，这些样品中提取的醛随着提取时间的增加而增加，并且随着提取温度的升高而急剧增加。甲醛、戊二醛是醛中最好的鞣剂，因为它们与低于ph7.0的赖氨酸的-氨基结合，形成胶原分子之间的交联键。(2)目前，《福利部法令第34号》规定的甲醛测定方法在皮革中的适用性进行了检验，然而，本研究的结果表明，提取时间…的规定在用人工汗液代替蒸馏水作为萃取剂的情况下，甲醛单宁胶原纤维中甲醛的萃取量随着碱性汗液提取时间的增加而减少。经甲醛处理的胶原纤维经亚硫酸氢钠溶液脱除后，可抽提物甲醛的量减少。在复鞣剂的情况下，阳离子和阴离子树脂复鞣剂中含有相对较多的可提取甲醛。其中一种含甲醛复鞣剂处理的铬胶原纤维甲醛含量超过了75mug/g的临界值，用亚硫酸氢钠溶液处理后，可提取甲醛的量减少。较少

The present study was carried out to establish the method for removingaldehydes from leather and for. Results obtained were summarized as follows.(1) The collagen fider and rabbit hair were treated with albehydes at different ph and concentrations, and the amount of aldehyde extracted from those samples were determined under various conditions of time and temperature. The results indicated that the aldehydes extracted from these samples increased with an increase of extraction time, and also increased drasticaly with increasing extraction temperature. Formaldehyde, glutaraldehyde have the best tanning potency among aldehydes, because these combine with -amino group of lysine below ph 7.0 to form the cross-linkage between collagen molecules.(2) At present, the determination of formaldehyde, prescribed in "welfare ministry ordinance No.34", is examined for applicability in the case of leathers,however, the results of this investigation suggested that the specification of extraction time … More to one hour might be problematical.(3) In case of the use of artificial perspiration instead of distilled water as extractor, the amount of formaldehyde extracted from formaldehyde tanned collagen fiber decreased with an increase in extraction time by alkaline perspiration. Perhaps, the extractable formaldehyde might be combined to the collagen fiber more tightly in alkaline perspiration.(4) When the formaldehyde treated collagen fibers were treated with solution of sodium bisulfife for removing agent, the amount of extractable formaldehyde decreased. In the case of retanning agents, cationic and anionic resin retanning agents were found to contain a relatively large amount of extractable formaldehyde. One of the chrome collagen fibers, which were retanned with formaldehyde contaning agents, had more than the critical formaldehyde value, 75mug/g. When these retanned collagen fibers were treated with sodium bisulfite solution, the amount of extractable formaldehyde decreased by this removing treatment. Less