Solvents will penetrate polyurathene and / or pigmented leather, my question would be why would you want to?
Many of the newer vehicles do not use natural leather hides anymore Approximately 80% of vehicle manufacturers are using (thermoplastic) polyurethane covered pigmented leather for their interior upholstery. Pigmented leather simply means that the finished leather or polyurethane covering has been coloured (you’ve never seen grey cows have you?) Are we to take care of the leather or the protective covering? The answer is to take care of the protective topcoat and the leather will take care of itself.
Compare automobile upholstery [finished pigmented leather] to a vehicles paint surface with a clear coat;
1. A base material (metal) with a colour coat of water-based polymer paint
[Leather hide pigmented with a water-based polymer resin]
2. A water-based polymer clear coat to provide protection
[Water-based polyethylene clear coating to provide protection]
3. Paint doesn’t need oils to feed it (whatever Zymol says); it’s not a living thing.
[Leather was removed from a dead animal, it’s then fat-liquored to preserve its oils and then sealed, and it doesn’t need oils to feed or condition it, even if they could permeate the various coverings]
Basic Leather care - Auto Geek Car Care, Car Wax and Auto Detailing Forum