Submitted to: Journal of American Leather Chemists Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/14/2004
Publication Date: 3/1/2005
Citation: Liu, C., Latona, N.P., Lee, J. 2005. Glutaraldehyde-tanned leather treated with tocopherol. Journal of American Leather Chemists Association. 100(3):102-110. Interpretive Summary: UV and heat can have a detrimental effect on the durability of automotive leather, especially for instrument panels and consoles, where temperatures reach well over 100°C. We have been working on the development of a finishing process using environmentally friendly antioxidants that improve the UV- and heat resistance of automobile upholstery leather. We applied Vitamin E to the grain layer of chrome-free leather. Following exposure in a Fade-Ometer, the treated samples were evaluated by colorimetry and mechanical testing for the efficacy of UV- and heat resistance. Observation showed that leather treated with Vitamin E resulted in significant improvement in strength retention and color fading resistance against UV radiation and heat. This research will expand the demand for domestic production of high quality, durable leather, thereby contributing to the viability of the domestic tanning industry.
Technical Abstract: Non-chrome-tanned (chrome-free) leather has gradually gained commercial importance, particularly for automobile upholstery applications. UV and heat resistance are very important qualities for automobile applications. We have developed an environmentally friendly finishing process that will improve the UV- and heat resistance of automobile upholstery leather. Tocopherol (Vitamin E) is a potent free radical scavenger and highly protective agent for collagen fibers against UV damage. We previously reported that the application of tocopherol to the grain layer of chrome-tanned leather improved its durability. The current study focused on non-chrome-tanned leather made with a glutaraldehyde-tanning process. We applied tocopherol to the grain layer of that leather and also studied the addition of tocopherol to the fatliquoring drums. Following exposure in a Fade-Ometer, the treated samples were evaluated by colorimetry and mechanical testing for the efficacy of UV- and heat resistance. A polarizing microscope equipped with a Berek compensator was employed to determine the birefringence of the untreated and treated leather collagen fibers to determine the treatment effects on the degree of orientation. Data showed that leather coated with tocopherol resulted in improved tensile strength retention and color fading resistance against UV radiation and heat. Leather fatliquored with tocopherol, however, did not show a similar improvement.