Nubuck is top-grain cattle leather that has been buffed on the grain side, or outside, to create a velvet like texture or nap. It has the characteristic of a slight nap, with the softest “hand” or tactile feel. Although nubuck is aniline dyed through it is commonly finish with a surface dye sometimes incorporating micro-pigment to cover up some natural blemishes. It looks similar to suede, but the difference is that suede is created from the flesh side of leather, whereas nubuck is created from the grain side of leather. As both nubuck and suede are napped leather, it is often incorrectly identified as suede. Leather is both hydrophilic and oleophilic, nubuck especially with its open nap absorbs both water and oil more readily, than any other smooth leather. It is generally more expensive than suede; fashion types include embossed, oil and wax pull-up effect. Fatliquor plays an important role when comes to maintenance to both reduce ingress of waterbased and grease stain; plumps the leather with fullness, reduces creases, and wrinkles. Leather protein-fiber component is amphoteric therefore, a leather-safe (pH 3 - 5) care product system is highly recommended to keep them clean while maintaining their chemistry integrity
Leather Stain Identification:
Appearance - Stain identification by appearance will show whether it the characteristic of a spill, rub-on, penetrated or deposited. It may also reveal dye or finishes damages cause by the stain.
Odor - Stain identification by smell can be very helpful in positive identification. Some of the more common odor may be moldy, smoke, putrid or ammonic from urine.
Color - Stain identification by color will also give a clue to the staining material. If the stain is red, it could be beverages, nail polish, lipstick, blood, or some other things. Color identification may not necessary be right; with time, a red bloodstain may turn to a stain that is tan to black. The color of the leather may mesmerize or alter the color of the stain.
Feel of Hand - Stain identification by feel of hand may help determine the stain types. For instance, if it is sticky and red it could be candy, beverages or other things that have sugar in them. If the stain is brittle and stiff, it may be nail polish, shellac or paint. If it smears, it may have grease base to it, such as lipstick.
Location - Stain identification by location may give a clue as to the makeup of the staining substance. If it is dark at the headrest or the edge of the armrest, it is most likely stain by body oil, grease and perspiration by hand or by head.
Buildup or Absorbed - A stain may take several appearances. The stain may be lying on top of the leather (buildup) on most pigmented leather or absorbed into the leather on most unfinished, aniline and nubuck leathers. Naturally, it could also be a combination of absorbed and built up. If it has been absorbed, this will be an indication that it was a liquid when it penetrates the leather. It should also alert us that it may have chemically changed the dye of the leather. An example of this would be a perspiration stain that has reacted with the leather dye and changed it in some way. This would occur more likely on dyed absorbent leathers. The perspiration could also have weakened the fibers of the leather. In any event, this leather may show a marked color change in that area after spotting, and possibly after cleaning. Examples of built up stains are paint and some foodstuff, etc. Examples of absorbed stains are beverages, wine, tea, coffee, etc. A combination stain may be lipstick, ink, mustard, etc. it will have part of its staining matter absorbed into the leather and part of it accumulated on the surface. A stain may also be a substance that has wet solvent-soluble and dry solvent-soluble components combined. An example of this would be gravy which contains grease, flour (from plant), and milk (from an animal). Paint type stains are readily detected because of their stiff nature and generally bright colors and they seem to be sitting on top of the leather. When identifying stains always try to a determine whether they are of a protein, cellulose, oil based, or a colloidal make-up nature. Three common types of soiling or stain are solvent-soluble, water-soluble and insoluble. Stains are frequently of a combination nature, and in most instances, there will be no information from the customer regarding the stain especially if they are bought used.
Identify the leather problem from the left column with the top row product recommended and the numbers denotes the sequence of steps. When leather have compound issue combine the soiling, stain and odor types as the cleaning phase-1 and the leather rejuvenating with Hydrator-3.3 > Fatliquor-5.0 as the second phase-2. Structural problem as third phase-3, Finishing as phase-4 and protection of the finishes as phase-5.