Use any high alkaline detergent for the nicoteen such as Powerclean or Powerfull will instantly disolve it but they are a bit soapy. Alternatively if you get stuck sugar soap will do it. Re unibond, if its the pva glue that had formed a skin you are talking about then a razor blade or safety scrapper as it is a natural moisture inhibitant, I doubt you will re-disolve it.