Study on the Chromium (VI) Formation in Leather after Ageing
Customer of tanneries and in particular footwear manufacturers currently ask even more often their leather supplier (tanners) for the evaluation of chromium VI presence after ageing of the leather (80℃, 24 h, R.H. 0-20％).This request originated also from a recent draft test method prepared by the Technical Committee CEN/TC 309 Footwear concerning the assessment of the propensity of chromium VI formation in footwear and footwear components (leather, coated leather, leather fibre board).Therefore, the aim of our research is to verify the possibility of chromium (VI) formation of semi-finished (wet-blue and crust) and finished leather by the use of two types of artificial ageing: dry ageing conduced in oven at different temperature conditions, 40℃, 60℃ and 80℃ and wet ageing in a climatic room with temperature control (40℃, 60℃, 80℃) and a given relative humidity (20％).The presence of chromium (VI) after artificial ageing has been also evaluated in leather samples stored for a definite time (72 h, 120 h, 288 h) at room temperature (16-20℃) and around 60-70％ relative humidity. The analytical results allow to state following considerations:?in crust and finished leather the chromium (VI) formation rises in accordance to the temperature increase?instead, in the investigated wet-blue, chromium (VI) is nor present at the temperature of 80℃?in general the dry ageing lead to a higher quantity of chromium (VI) formation in comparison to the wet ageing test method?the leather samples artificially aged after conditioning at room temperature, show a reduction of the chromium (VI) content as regards the samples directly submitted to the ageing test.
chromium (VI) ageing chemical analysis physical test storage
Girardi V. Calvanese G. Naviglio B. Zollo F.
Stazione Sperimentale per lIndustria delle Pelli e delle Materie Concianti Via Nuova Poggioreale 39 Universita Federico II Napoli, Dipartimento di Chimica delle Sostanze Naturali Via D.Montesanto, 49,
国际会议
北京
英文
26-31
2009-10-11（万方平台首次上网日期，不代表论文的发表时间）