Retanning with TFL

The latest TFL acid retanning system combines the advantages achieved when working in a low pH-range with those in a high pH-range without actually raising it and features Sellatan AR liq. This is a conditioning agent used to prepare for the retanning/fatliquoring processes for all types of leather, without the need for a neutralising step. The main benefits of the new TFL acid retanning system are: an increase in the useable area of the leather by improving tightness without sacrificing inner softness and penetration. The acid retanning technology is very interesting for hides with poor structure or wet-blues which are very well opened up. The benefits of the system can be explained by its manipulation of the pH and the IEP (isoelectric point) in order to achieve a sufficiently anionic character of the substrate. IEP: acid retanning technology versus standard wet-end formula is shown in the following graph which illustrates the development of the IEP of traditional neutralisation compared to the acid retanning technology. A recent retanning agent from TFL, Sellasol BC/7 has selective filling properties. In fact, TFL say that the product has an outstanding filling effect and is preferably used to fill the flanks (the loose structured areas) of both hides and skins. Sellasol BC/7 gives softness and tightness with a fine and smooth grain and does not have any significant bleaching effect on dyeing. In addition, it ensures an even break to the leather after dry milling and imparts excellent buffability and dry shaving properties to hides and skins - an important aspect for the preparation of suede and nubuck articles.