The Cr.AB process: A new ecological process for the transformation of pickled hides into leather Part 3: Fatliquoring

EC derivatives, environmental protection, regional requirements, clean prod uction of leather at every stage has become a major preoccupation for indus try, including leather manufacture. Many products such as tanning agents, o ils and fats, dyes, pigments and finishing products, become an integral par t of the leather. The chemicals not taken up by the leather are released to the environment. A more environmentally friendly process, the Cr.A.B. proc ess-an ecological chrome-tanning process with a high exhaustion rate of the tanning liquor and dyebath with low chromium and dyestuff-has been propose d in previous articles. The following shows the main characteristics of fat liquoring in the Cr.A.B. process. Because of a high amount of greases obtained when degreasing seal skins bef ore tanning, we tried to utilise these by-products in the Cr.A.B. process. In an ancilliary but related study fatliquors were prepared from seal oil u sing sulphation and with anionic surfactants. The properties of the product s were studied and they were compared to a commercial fatliquor by applicat ion to Cr.A.B. leather. The results were encouraging. The Cr.A.B. process appears to offer attractive improvements both in reduci ng waste and in facilitating the recycling of liquors whilst producing sati sfactory leathers. The environmental benefits have been quantified.