There are many variations of leather available in the market today and it is useful to know the different qualities available when selecting an office chair or reception chair or sofa in leather. These variants are generally called full grain, top grain, corrected grain, split, bonded and finally PU or bi-cast. The amount of surface coating applied determines whether the item can be described as genuine.
The hides of full grain have not been sanded, buffed or snuffed to remove any imperfections on the hide surface. Full grain will show natural marks and imperfections. It is the most expensive.
To produce top grain and split products, thicker leathers are selected and put through a splitting machine to slice the leather into two layers. The top layer is called top grain and is the second highest quality. This top grain is thinner and more pliable than full grain. The surface has been sanded and a finish coat added to remove imperfections. It is normally less expensive than full grain, more pliable to work and has a greater resistance to stains.
The second, or lower layer, from this splitting process after the top grain has been separated is fibrous and left without a grain surface. This fibrous layer can be used for suede or it can have an artificial grain surface applied, which is embossed with a leather grain. This is known as split leather.
Corrected leather has had imperfections sanded off and an artificial grain applied to the surface. Corrected grains are often used to make pigmented leathers.
Bonded leather is not a true leather but contains leather material. It is normally composed of fibres which are bonded together to create a look and a feel similar to that of leather. This process creates durable upholstery. This process is more environmentally friendly than leather production for those seeking a greener product.
Bi-cast or PU has a layer of polyurethane applied to the surface, which is then embossed to provide the grain. The use of the term ‘leather’ in relation to this bi-cast treatment is considered a misrepresentation.