Farbkuppler

Farbkuppler is a German term that translates to "color coupler" in English. It refers to a chemical compound used in photographic processes, particularly in color photography. Farbkuppler are essential components in creating the vibrant colors seen in traditional film and some photographic papers.

During the development of color film, exposed silver halide crystals are converted into dye images. Farbkuppler are the chemical agents that react with the oxidized developer to form these dyes. Different types of Farbkuppler are used to produce the three primary colors: cyan, magenta, and yellow. Each layer of color film contains a specific Farbkuppler that generates one of these colors.

The specific chemical structure of a Farbkuppler determines the hue and stability of the resulting dye. Early color photographic processes relied on mobile Farbkuppler that diffused during development, leading to potential color shifts. Modern processes utilize immobilized or so-called "coupler-in-situ" technology, where the Farbkuppler is directly incorporated into the emulsion layer, resulting in sharper images and more stable colors. The development and refinement of Farbkuppler technology have been crucial to the advancement of color photography.