>>> chair on the left is darker from more use - body oils.
Body oil, grease and sweat accumulation besides darkens the color, the sweat components is causing a gradual denaturing of the leather. Leather is an amphoteric material and as the protein fibers shift ionic negative (-ve) from the effect of the sweat. All the ionic negative composition like the tanning-agents, dyestuff and fatliquor breaks its hydrogen bond and the leather slowly revert back to rawhide. In most cases the already weaken finishing takes a toll and disintegrate during the degreasing process. The penetrated oil, grease and sweat sometimes penetrate through to the suede side and it is easier to remove from the more porous suede side then the tighter smooth skin side. Cushion that has a zipper would be better remove from the reverse suede side to reduce physical damages to the smooth skin sides. Detailed degreasing may also remove any surface damaged skin cells, thus loose it’s smooth texture that may reveal like “nubuck” with a “finger writing effect” when dry. Denaturing of the leather may manifest as tackiness where the tanning agent migrates and corrective effort is by restoring the protein fiber ionic positive (+ve) by using a low pH degreaser like Degreaser-2.2 (pH value 2.2) in combination with Acidifier-2.0 (pH value 2.0) as rinse. Dyestuff may show on a white towel during the soil and rinse extraction process. Acidifier-2.0 treatment will further reduce dye bleeding. Hydrator-3.3 is used for deep within the leather structure soil movement to the surface and prepares the leather for Fatliquor-5.0 before it dries, otherwise cracks may manifest if the leather does not received sufficient fat and oil to a 14% moisture level.
>>> The ottoman has lost the blue undertone and is worn;
The original color is most probably maroon color, which has a percentage of black and blue is part of black. That’s why when black fades, it turn bluish or greyish.
>>> left side is more worn and lighter than the right.
Physical wear is control with a buttery-feel protector like Protector-B, Protector-B+ comes with a classic leather scent. When smooth leather wears, it becomes the feel of nubuck with a fine finger writing effect. Restoration is with the help of Adhesor-73 (tint with the desired color) to smooth it out.
>>> Ottoman closeup: watermark
Watermark rectification is by CleanPro-1.5 > Acidifier-2.0 > Hydrator-3.3 system (note the product suffix number, it is the pH value of the product). When the entire leather is treated the watermarks (fugitive dyestuff) redistribute to even out appearance.
>>> color differences:
High-end leather is more prone to fading, as most of these are the finer aniline finishes versus pigmented.
>>> inside arm: not faded much
In order to compensate the color intensity, a fine airbrush like Paasche double action will be helpful. The air pressure has to be between 80 and 100 psi, with reduce feed and increase airflow.
>>> scuff mark on side of chair
The roughness is smooth with Adhesor-73 with color tint, flaps that stick out will need Bond-3D > Bond-7A to smooth it out accordingly. Color refinishing returns to new like condition.
>>> Under side of chair cushion laying on the lightest side of the ottoman. Cushion is shiny and dark, ottoman is dull, with fine lines, and worn to lighter shade.
There are two levels of restoration, one is below surface to the leather structure and Fatliquor-5.0 is used to replenish diminishing fat and oil. Any over-stretching or looseness of the leather structure is strengthened with Impregnator-26. When the leather structure returns back to its integrity, the above refinishing begins with Adhesor-73 > Aniline-76 > AnilineTop-76G > Protector-B/B+
>>> Empty chair cushion shows wear, fine lines and cracking. Still feels ok, not too dry.
This decision is subjective - it will depend on the desired outcome.
Roger Koh
Leather, Skin & Hair Care System Formulator
Consultant / Practitioner / Instructor / Coaching
web: www.leatherdoctor.com
forum: www.leathercleaningrestorationforum.com
email:
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