What you see is leather that has been saturated with hand oils from the people who sit on this furniture. The pH of the person's skin output is considerably more acidic than the leather. This pH differential causes a chemical reaction as the pH of the leather (about 5.0) and the pH of the individual using the furniture are quite different. This is NOT a universal problem but nonetheless its a common problem for us as professional leather technicians.
The chemical reaction mentioned breaks down the fiber structure of the leather, literally rotting it.
Once leather reaches this state, it can not be saved. Instead the offended panel requires replacement. That is an expensive procedure and may not be justified. So, don't let your leather get to this state.
With Advanced Leather Solutions oil extraction procedure, you can save the piece if you draw out the offending body oils before they have this type of irreversible impact.
Copyright 2009, Kevin Gillan
