Polyurethane, or PU, coated leather is split hide leather that is bonded and covered with a polyurethane coat, and then embossed with grain patterns to simulate the appearance of top grain leather. PU is also known as bicast leather and split hide leather.
PU coated leather is a cheaper alternative to top grain and aniline leather. This material is used mostly for glossy shoes and for furniture upholstery. While purists may scoff at PU coated leathers as being mere faux leather, it does simulate the look and feel of natural top grain or aniline leather to a certain extent, it is easier to clean and it is available in different colors. However, PU coated leather does not become supple and develop a patina over time just like a top grain leather and it is susceptible to cracking, sometimes as early as a few months.
Split leather are essentially a by-product of leather manufacturing. The skin of a cow is removed in a single layer in a slaughterhouse and is then taken to a tannery for processing. The outer layer, which will eventually become aniline or top grain leather, is shaved off, leaving the inner layers behind. These inner layers are called split hides, and to make them useful, they are coated with a layer of polyurethane. The resulting material is then used for affordable handbags, belts, shoes and furniture upholstery.