The rapid growth in the high-tech uses of dyes, particularly in ink-jet printing, is beginning to make an impact. Although the volumes of hi-tech dyes will remain small in comparison to dyes for traditional applications, the value will be signifi- cant because of the higher price of these specialized dyes.Leather is a very complex and heterogeneous substrate. Once the animal has been slaughtered, the hide or skin has to be removed, cleaned, depilated, and tanned in the so-called "beam house" process. The term "hide" is used for the outer covering of animals with a body surface area of more than 1 m2 like bovines, and the term "skin" for that of smaller animals like sheep, goats, and pigs. Large proportions of sheepskins are used for fur production.