Zyglo ZP-9F is a ready to use suspension of white developing particles in a fast drying solvent. ZP-9F is non-halogenated and produces an opaque white coating, which provides an excellent contrasting background for Spotcheck or Zyglo penetrant indications.

METHOD OF APPLICATION

Zyglo ZP-9F should be applied by spraying only, as dipping or brushing will cause excessive solvent action on the penetrant in discontinuities. On standing, developer particles will settle out of suspension and must be re-suspended before applying.

Developers should be applied only after the test surface has been cleaned of excess penetrant, and the cleaning medium has been dried off. Non-aqueous developers should be sprayed in thin even layers, which just wet the surface. Too wet a spray will cause excessive bleeding and running of indications; whereas too dry a spray will result in slow indication development as well as possible loss in overall sensitivity due to limited solvent action.

ZP-9F’s unique formula provides a thin coating that hides surface blemishes. A thick coating is not required for this effect and is undesirable as masking of indications could result. ZP-9F gives a dense coating which is ideal for fluorescent inspection. With Zyglo® penetrants, inspection is performed with a black light with a peak wavelength of 365 nm, such as a Magnaflux® ZB-100F Fan-Cooled Black Light. Cracks will fluoresce a yellow/green color. Note! A general greenish fluorescent developer film indicates incomplete removal of surface penetrant.