Submitted to: American Leather Chemists Association Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 3/12/2008
Publication Date: N/A
Technical Abstract: Genipin is a non-toxic iridoid compound, extracted from the gardenia fruits, and, because of its low cytoxicity, is replacing both glutaraldehyde and formaldehyde as a crosslinking reagent. In prior research we had shown the potential of chemical (glutaraldehyde) and enzyme (transglutaminase) modified gelatin as fillers for leather. In this present study, we investigated whether genipin-modified gelatin products would also be applicable. We initially determined optimal reaction conditions of genipin with gelatin for the purpose of creating products with suitable molecular weight distributions, viscosities and melting temperatures that would be appropriate for them to be used as fillers in leather processing. We applied the products to blue stock and, using epifluorescent microscopy, verified that these products were uniformly distributed through the blue stock and were not removed during washing. We scaled up these treatments and applied them to different areas of the hides; subsequently the pieces were retanned/colored/fatliquored (RCF), mechanical properties determined and subjective evaluation carried out. The mechanical properties were not significantly different from those of the control pieces and, with respect to subjective evaluation (handle, fullness, break and color), the treated products fared better than the controls. The hydrothermal stability of the blue stock and RCF samples showed that there was an improvement in the shrink temperature in the genipin/gelatin-treated samples. Thus, genipin-modified gelatin has the potential to provide another environmentally safe alternative to the more conventional post-tanning processes.