Leather technology

In 1939, Jordan Lloyd was awarded the Fraser Muir Moffatt Medal by the Tanners Council of America for her contributions to leather chemistry. Her change in career direction did not diminish her productivity, and over her lifetime she authored or co-authored over 100 scientific papers, together with planning and contributing to the three-volume Progress in Leather Science, 1920-45, the classic textbook of leather technology. 

Figure 1 Kallab s original, patented, apparatus for testing the photostability of leather products (4). Source Courtesy Journal of Society Leather Technology and Science.

Thorstensen T C (1993), Practical Leather Technology, Fourth Edition, Florida, Krieger Publishing. 

T. C. Thorstensen, Practical Leather Technology, R. E. Krieger Publishing Corp., New York, 1976, pp. 190-207. 

During the third quarter of the twentieth century, with improved nonwoven fabrics, man-made leathers finally succeeded in simulating leather to such an extent that they are nearly identical in appearance, physical properties, and stmcture. These leathers have enjoyed success in all leather-use areas. With the technology of microfibers, they continue to evolve both in quaUty and quantity. 

Man-Made Leathers. These materials contain a nonwoven fabric which is impregnated with a polyurethane to improve fiexibiHty, processibiHty, and conformabiHty (Fig. 9). Advanced man-made leathers contain microfibers as fine as 0.03 tex (0.3 den) or less to imitate coUagen fiber bundles, thereby attaining the soft feel and appearance essential for soft leather use. Polyurethane in the substrate is usually provided with porous stmcture by poromeric technology. The coating layer is also porous in the two-layer type man-made leathers (5—10). 

The detergent industry is the largest user of industrial enzymes. The starch industry, the first significant user of enzymes, developed special symps that could not be made by means of conventional chemical hydrolysis. These were the first products made entirely by enzymatic processes. Materials such as textiles and leather can be produced in a more rational way when using enzyme technology. Eoodstuffs and components of animal feed can be produced by enzymatic processes that require less energy, less equipment, or fewer chemicals compared with traditional techniques. 

The TAN BREF document is at the moment revised, but a new version is expected to be adopted by the end of November 2012. The document contains information about the leather industry in general, the leather industry in EU, conventional technologies used, BAT and also emission levels which are possible to be achieved by the use of BAT. The document includes information of substitution of chemicals in the industry. However, the document does not specifically address human health risks due to chemicals in the products since that subject is covered by other legislation within the EU. However, the document gives guidance on use of alternative chemicals as an alternative to the use of several problematic chemicals. 

Nagghappan, L. Leather Tanning Effluent Treatment, Lenox Institute of Water Technology Lenox, MA. Master Thesis (Wang, L.K., Krofta, M., advisors), 2000 167 pp. 

A biofilm electrode reactor (BER) has been used by researchers at the University of Cincinnati to dechlorinate pentachlorophenol (PCP), a halogenated organic used in wood and leather treatment. This technology is not commercially available. All information is from the developer and has not been independently verified. 

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