A nonsilver photosensitive reproduction element which comprises a support bearing a layer of a photosensitive composition which comprises (1) at least one thermoplastic binder, (2) a photosensitive system consisting essentially of (a) a hexaarylbiimidazole compound and (b) a dihydropyridine compound; and optionally (3) a plasticizer, and (4) a thioamide, thiolactam or thiocarbanilic acid ester of the formula: <IMAGE> wherein R1 and R2 are as defined. The photosensitive element is useful in preparing negative tonable images.
Photosensitive reproduction elements for forming negative tonable images