Variable sensitivity water washable dye penetrant

Abstract

Variable sensitivity biodegradable water washable dye penetrant compositions for use in non-destructive dye penetrant inspection of parts, such compositions basically consisting essentially of an organic dye, preferably a fluorescent dye, and a carrier or solvent for said dye, in the form of a surfactant comprised of certain straight chain, primary, aliphatic oxyalkylated alcohols, particularly biodegradable surfactants comprised of the nonionic condensation products of linear primary aliphatic alcohols having from 10 to 18 carbon atoms, with ethylene oxide and propylene oxide, preferably in the form of a mixture thereof, such as the material marketed as Plurafac A-24, or in the form of certain ethoxylated secondary alcohols, particularly the biodegradable nonionic surfactants comprised of ethoxylates of a mixture of secondary alcohols having linear alkyl chains of from 11 to 15 carbon atoms, such as Tergitol 15-S-5 or Tergitol 15-S-9, the variations in sensitivity being provided by the addition to the above basic composition of controlled amounts of the above surfactant component, the resulting compositions all having substantially the same water washability. In the method of application of the dye penetrant composition of the invention, such composition is applied to the surface of an object containing cracks and flaws, water is applied to the surface of the object to remove excess dye penetrant composition from the surface without removing such penetrant from the cracks and defects, and with or without a developer, the surface of the object is viewed under suitable lighting conditions, e.g. ultraviolet or black light when the dye in the penetrant is a fluorescent dye, to locate any cracks or defects in the surface of the body as indicated by colored traces from the dye penetrant remaining in the cracks and flaws.

Dependencies are inferred from the claim text.