Most commercial microforms are silver halide. Diazo is sensitized layers composed of diazonium salts that react with couplers to form dye images. The color of the image is determined by the composition of the diazonium compound and the couplers used in the process. The image may be black, violet, or another color. Vesicular describes films in which a light-sensitive component is suspended in a plastic layer.
Vesicular films are commonly blue or beige.
Use for microopaques. Microopaques are not on film. The copy generation of the microform. The first generation is the camera master or COM recorder master. Microforms of any generation employed mainly for the production of other microforms.