Diluting the cyanoacrylate monomer in a non reactive solvent can reduce the thickness of the resulting polycyanoacrylate layer; however, thinness alone fails to solve all of its problems. Primer B also needs to produce a microscopically structured polycyanoacrylate layer that can bend and stretch with the silicone rubber and that binds well to both that silicone rubber and the adhesive or coating above it. To achieve those goals, the solvent used to dilute the cyanoacrylate must be carefully chosen.