Amidol

Amidol^[1]

Names
IUPAC name 2,4-Diaminophenol
Identifiers
CAS Registry Number	95-86-3 Y 137-09-7 (dihydrochloride)
ChemSpider	6996 Y
InChI InChI=1S/C6H8N2O/c7-4-1-2-6(9)5(8)3-4/h1-3,9H,7-8H2 Y Key: XIWMTQIUUWJNRP-UHFFFAOYSA-N Y InChI=1/C6H8N2O/c7-4-1-2-6(9)5(8)3-4/h1-3,9H,7-8H2 Key: XIWMTQIUUWJNRP-UHFFFAOYAD
Jmol-3D images	Image Image
PubChem	7266
SMILES NC1=CC(N)=C(O)C=C1 Oc1ccc(N)cc1N
UNII	NNB4I01PA7 Y
Properties
Chemical formula	C6H8N2O
Molar mass	124.14 g/mol
Appearance	Colorless solid
Melting point	78 to 80 °C (172 to 176 °F; 351 to 353 K)
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Y verify (what is: Y/N?)
Infobox references

Amidol is a colorless crystalline compound with the molecular structure C₆H₃(NH₂)₂OH. It is a dihydrogen chloride salt and is used as a photographic developer. It was introduced as a developing agent for photographic papers in 1892. It is unusual amongst developing agents as it works most effectively in slightly acid conditions rather than the strongly alkaline conditions required for most other developers. As amidol ages it changes color to a dark red-brown. Developing dishes and equipment used to prepare amidol solutions are also frequently stained brown, a stain that is very persistent.

Prints developed in amidol are typically a very warm brown-black colour, but overdevelopment can quickly lead to chemical fogging.

References