. "The ink might be harder than the base plastic.See: http://www.inkcups.com/inks-thinners/sc ... fault.aspxhere is a line from their marketing blurb describing one of their inks:J3's great opacity, abrasion resistance and superior resistance to chemicals such as alcohol, acids and alkali make it a great vinyl and plastic printing ink for industrial applications.It looks like they have gone out of the" . . . .