Diazo film is a type of photographic film that is commonly used in the production of blueprints and other technical drawings. The film is coated with a light-sensitive emulsion that contains a chemical compound called diazonium, which reacts to ultraviolet light. When the film is exposed to light, the diazonium compounds break down, creating a blue dye that forms the lines and details of the original drawing. Diazo film is typically used in conjunction with a large-format printer or plotter, which produces a high-quality, detailed print of the original design on the film. The film is available in various sizes and thicknesses, and can be easily cut or trimmed to fit specific printing requirements. Diazo film is commonly used in architectural, engineering, and construction industries, where it is used to produce blueprints, schematics, and other technical drawings. It is also used in the manufacturing of printed circuit boards and other electronic components.