What is Leather Dye?
Leather dye is a product used to dye leather when it is been tanned, depending on the type of tanning process carried out will depend on the colour of the leather prior to being dyed.
Tannins from plants give a brown shade, while chrome tanning gives a blue shade called a wet blue leather. Synthetic tanning agents and taw with alum give a whiteish shade.
Leather hides are made up in several layers (see diagram)
How Pigmented Leather Is made Leather Dye
Aniline leather dyes are transparent dyes that don’t coat the leather skin but dye the hide in shades. Once skins have been aniline dyed they are selected to be used for other uses and then can be pigment coated with binder pigment paints. After the pigmented leathers is given a clear coat lacquer sealer it provide a fully waterproof coating layer on the surface.
With any dye or pigment paint these can fade or wear off with use and age and sun light attacking the coating.
When skins are tanned they are placed in barrels and the dyes penetrate the hide as they are moved around in the barrels, these are then rinsed to avoid dye transfer and to remove excess dyes.
All absorbent leathers are aniline, suede, nubuck and they are all dyed this way first of all. Aniline dyes can only be used to dye a darker shade and the same applies when restoring aniline leathers, this will dye a darker shade as the porous leather absorbs the dye liquid.
Prior to Aniline Dyes other dyes were used, but due to them being harmful to your health they are no longer used and aniline dyes are now used. Azo Dyes can be associated with bladder and liver cancer and for this reason they are not used anymore and the transparent aniline dyes are now used for dyeing leather.