Surface coatings pigmented with a 1-(dichloro-4'-sulfamoyl or substituted sulfamoyl-phenylazo-2-hydroxy-3-phenylcarbamoyl or substituted phenylcarbamoyl-naphthalene

Granted: Nov 18, 1986 Filed: Oct 10, 1984

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.