Comparison of Typewriter Ribbon Inks by Thin-Layer Chromatography

Abstract

Abstract Examiners of questioned or disputed documents are frequently asked to ascertain whether or not the text of a typewritten document has been altered by the use of either a different typewriter or the same typewriter at a later date. Any technique that can distinguish among the various commercially available typewriter ribbon inks is a potentially valuable tool to the examiner of questioned documents.