10-24-2015, 08:14 PM
What I do is try a few different things. If it is a water soluble ink (like Philcos) then try mineral spirits on a Qtip at the very edge of the print to see if the ink comes off. If isn't water soluble then just water is fine, I try to stay away from soaps and cleaners. Most of the time they are just a little dirty anyway.
Terry
Terry