Color Developing Agent 1 (CD-1) is the first in the series of color developing agents used in developing
color films. It is the organic compound ''N'',''N''-diethyl-1,4-benzenediamine (DPD), which is usually in the form of the mono
hydrochloride salt.
In color development, after reducing a
silver atom in a
silver halide
A silver halide (or silver salt) is one of the chemical compounds that can form between the element silver (Ag) and one of the halogens. In particular, bromine (Br), chlorine (Cl), iodine (I) and fluorine (F) may each combine with silver to prod ...
crystal, the
oxidized developing agent
combines with a color coupler to form a
color dye
A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution and ...
molecule.
Arthur Thomas Palin, a Fellow of the
Royal Society of Chemistry, developed a widely-used color based method of
water testing using DPD to indicate the
chlorine content of treated water.
See Also
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Color Developing Agent 2
Color Developing Agent 2 is the second in the series of color developing agents used in developing Color photography, color films. It is commonly known as CD-2 and is chemically known as 4-diethylamino-''o''-toluidine, 1,4-benzenediamine, N4,N4-d ...
*
Color Developing Agent 3
*
Color Developing Agent 4
The fourth in the series of color developing agents used in developing Color photography, color films, commonly known as CD-4, is chemically known as 4-(N-Ethyl-N-2-hydroxyethyl)-2-methylphenylenediamine sulfate. In color development, after reduci ...
References
{{organic-compound-stub
Photographic chemicals
Anilines