Cyanotype Pretreated Fabric Sheets by Jacquard make producing Prussian Blue Monochromatic prints easier than ever before. Simply place the object or film negative on top of fabric and expose to sunlight or UV. After exposure, prints should be processed in a tray of cool water and allowed to air dry. Cyanotype is an antique photographic process developed in the mid-19th century for reproducing photographs. Includes 10 sheets (8.5 x 11 in).