[DuPont] A registered trademark for a photosensitive paper. Dylux® is sensitive to light in both the visible (400-500 nm) and ultraviolet range (200-400 nm). The paper has an initial yellow covering that becomes white with exposure. After exposure, the sheets are developed without the use of chemicals. The cover sheet is removed and the paper is exposed to a low intensity ultraviolet light where the previously unexposed areas turn a dark blue. Dylux® is used in lithography, photoproofing and information recording systems. It has been used to examine watermarks.
R.A.Allison, "About Dylux® Proofing Paper" in Archive of Watermarks and Papers in Greek Manuscripts published online at: Guide to Archive