Dye coupler
（重定向自Color coupler）
Dye coupler is present in chromogenic film and paper used in photography, primarily color photography. When color developer reduces ionized (exposed) silver-halide crystals, the developer is oxidized, and the oxidized molecules react with dye coupler molecules to form dye in situ. The silver image is removed by subsequent bleach and fix processes, so the final image will consist of the dye image.