1. Wrinkle’s - similar to a paints clear coat, upholstery urethane is classified as a semi-solid permeable membrane, being a thermosetting polymer (elastomers) it remains flexible while retaining its tensile strength, to enable it to expand and contract, following the temperature fluctuations (elasticity) of the substrate and is therefore subject to show wrinkle’s.
These can be lessened by using a damp (microwave heated) towel, which will cause the urethane to contract slightly. The foam, leather hide and its urethane covering are subjected to compression (the weight applied by people sitting on them) which causes them the stretch, which in turn produces creases (wrinkles). If they become excessive it may mean that the foam is compressed to the point it will no longer ‘rebound’ and should therefore be replaced
2. Pigmentation (Colour) Replacement - Certain areas of your vehicles leather interior like seats, upholstery, side mouldings and steering wheels inevitably start to show signs of wear, even if well taken care of, that spoil its overall impression. Often these imperfections are not serious and are simply colour that has worn off or light scratches in the leather surface which can be removed and will disappear with the right application technique and leather pigmentation.
“Leather Pigmentation (Colour) Renovation” - http://www.autopia.org/forum/autopia...ml#post1479003