Single-layer and multilayer imageable elements have a substrate and at least one imageable layer and can be used to prepare positive-working lithographic printing plates. The imageable elements also include a radiation absorbing compound and a solvent-resistant polymer binder comprising an --N(R)--C(.dbd.X)--N(R')--S(.dbd.O).sub.2-- moiety that is attached to the polymer backbone, wherein X is O or S, R and R' are independently hydrogen, halo, or an alkyl group having 1 to 6 carbon atoms. This solvent-resistant polymer binder is located in the imageable layer closest to the substrate and provides improved chemical resistance.