| abstract |
A steam sensitive composition and a sterilization indicator composition which change in color only upon exposure to all of the conditions necessary for sterilization, that is, steam at a prescribed temperature for a prescribed period of time. The steam sensitive composition contains a metal complex and an exchange ligand. The metal complex is bis(dimethylglyoximato)nickel, bis(2-furyldioximato)nickel, zirconium chloranilate or bis(nioximato)nickel; and the exchange ligand is either 1) an aminocarboxylic acid which comprises from 1 to 6 carboxylic acid groups and from 1 to 4 amino groups, and its salts; or 2) citric or tartaric acids and their salts. The sterilization indicator contains as main components the steam sensitive composition described above, a binder, a solvent and preferably a color-change rate regulating component. The rate regulating components may be a cyanate or thiocyanate salt, and/or tartaric or citrate acid or their salts. |