SLIDE BLANK

A slide blank (10; 90; 100) comprises a support (12) at least part of which is essentially transparent; an imageable layer (20; 30; 30'; 60; 60') superposed on one face of the support (12), the imageable layer (20; 30; 30'; 60; 60') not being substantially sensitive visible radiation but comprising a color-forming composition, which, upon imagewise exposure to actinic radiation, forms a colored material, thereby forming in the imageable layer (20; 30; 30'; 60; 60') an image which can be viewed in transmission; and a protective layer (26; 50; 80) superposed on the imageable layer (20; 30; 30'; 60; 60') on the opposed side thereof from the support (12), at least part of the protective layer (26; 50; 80) being essentially transparent; the support (12), imageable layer (20; 30; 30'; 60; 60') and protective layer (26; 50; 80) being secured together to form a slide blank having a thickness of at least 0.8 mm, and the thickness of the protective layer (26; 50; 80) being such that no part of the imageable layer containing the color-forming composition is more than 0.2 mm from one external surface of the slide blank. This slide blank can be imaged to produce a ready-mounted slide.