Dye solution flaw inspection method

Claim 1

THE METHOD OF INSPECTING A PART FOR SURFACE DEFECTS WHICH COMPRISES APPLYING TO A SURFACE OF SAID PART A SOLUTION OF A DYE IN A PENETRANT LIQUID CONSISTING OF A VOLATILE LIQUID AND A RELATIVELY NON-VOLATILE LIQUID HAVING A HIGH SURFACE TENSION THAN SAID VOLATILE LIQUID, SAID RELATIVELY NON-VOLATILE LIQUID CONSISTING ESSENTIALLY OF AN OXYGEN-CONTAINING ORGANIC LIQUID, REMOVING PENETRANT LIQUID FROM THE SURFACE TO PERMIT EVAPORATION OF PART OF THE VOLATILE LIQUID FROM THE PENETRANT LIQUID REMAINING IN THE DEFECT WHEREBY THERE IS AN INCREASE IN THE SURFACE TENSION OF LIQUID IN SAID DEFECT, AND DEPOSITING ON SAID SURFACE A LAYER OF FINELY DIVIDED PENETRANT LIQUID ABSORBING MATERIAL OF A COLOR CONTRASTING WITH THAT OF SAID DYE WHEREBY PENETRANT LIQUID WILL BE ABSORBED IN SAID DEPOSIT TO FORM A VISIBLE TRACE.