Fotospeed Cyanotype Sensitizer, is used in the alternative photographic process of Cyanotype printing. The Cyanotype process is the first successful non-silver photographic print process and dates back to 1842.
Its notable blue image color is a result of its origins in Prussian Blue a derivative of iron. It has long been used commercially as "Blueprints."
Store the sensitizer solution in a brown bottle in a dark, dry location. Shelf life should be in excess of one year if stored properly.