Oblon, Spivak, McClelland, Maier, & Neustadt, P.C.
Use of compounds which absorbs and fluoresce in the IR range as crack-detecting agents
 Compounds from the class consisting of the phthalocyanines, naphthalocyanines, the aminium compounds of aromatic amines, the methine dyes or the azulenesquaric acid dyes, which have their absorption maximum in the range from 600 to 1,200 nm and a fluorescence maximum in the range from 620 to 1,200 nm, are used as crack-detecting agents. 
BASF Aktiengesellschaft
G
G01N
inventional
J urgen Bernhard Peter Gerhard
Kipper Albert Neumann Wagenblast