Polyurethane leather is an outstanding substitute for natural leather. The increasing importance of polyurethane leather is due in part to its economical production, but above all to its property profile which is at least equal, and in some aspects superior, to that of natural leather. Although it is now nearly impossible to distinguish the two materials in terms of appearance, polyurethane leather based on Impranil or Desmoderm from Bayer MaterialScience AG stands out in particular through its better durability. Furthermore, individual properties can be specifically modified to suit the respective application, eg more comfortable seating in automotive interiors or good abrasion resistance, which is essential in the case of soccer balls.

In the manufacture of furniture, other requirements are important too. What is needed are highly flexible materials which allow the production of fold-free upholstery. Other important properties are good slip behaviour and outstanding hydrolysis stability. Fashionable colour effects can only be achieved if there is considerable scope in the colour design of the upholstery. At the Asia Pacific Leather Fair in Hong Kong from March 29 to April 1, 2004, Bayer MaterialScience will exhibit a designer chair upholstered with blue polyurethane leather at Stand K02 in Hall 3. The upper layer is based on a monoelastic fabric coagulated with Desmoderm KEN/KCW. This material was then transfer-coated with purely waterborne polyurethane dispersions based in particular on Impranil VP LS 2384. With this process, the coating is applied to a release paper onto which the coagulated base material is then pressed and thus bonded. The release paper often already possesses a structure (grain) which is transferred to the product.

In addition to the very good durability and abrasion resistance of the surface and the outstanding lightfastness of the material, the environmental compatibility through the use of purely waterborne dispersions is particularly noteworthy.

Additional information about textile coatings, polyurethane synthetic leather and coagulation can be found at [http://www.bayercoatings.com]