If you are no snob about top-of-the-line leather upholstery, then bicast is a good alternative to high-end, high-cost leather upholstery. Bicast (also called by-cast and PU leather) contains leather, but it is a coated, lower-grade leather, that does not breathe or age naturally. In fact, some countries (including New Zealand) disallow manufacturers from advertising it as "leather." Still, bicast is far more economical than top-grade cowhide, is stain resistant and can be quite durable when it is made well.
The leather used in bicast is cowhide but what is called a "split." Thick cowhide is split into several layers, the smooth outermost layer being the top grain. The inside layers are used for suede or treated to appear like top-grain hide.
Bicast leather is coated in polyurethane or PU, which is why bicast is also known as "PU leather." Polyurethane is an organic polymer typically found in gaskets, foam, adhesives and sealants. The smooth polyurethane coating gives the split leather a smooth, top-grain finish.
While natural leather breathes, bicast leather is completely sealed by the polyurethane. So, it may feel less comfortable on a warm day. Bicast also feels stiffer, and it is. It does not stretch, with its polymer coating, as natural leather does. Finally, it does not age or take on a patina as untreated leather does. This can be both an advantage and a disadvantage; a club chair may never take on an antiqued look, but a couch will look newer for a longer time. Some owners complain about a chemical smell, which tends to fade.
Because of its polymer coating, bicast leather is stain resistant. Ink and liquids do not penetrate the polymer. So, dried ink is fairly easily removed and spills wipe up easily. Bicast may also be cleaned with common household agents, like Murphy's Oil Soap or a window cleaner, instead of more expensive leather-cleaning products.
Bicast "offers a high-fashion look at an entry-level price," according to a spokesperson for furniture maker Omnia. Bicast leather is priced about 20 per cent lower than a lower-grade but top-grain cowhide.