is dried it is exposed to actinic radiation preferably ultraviolet light through a suitable photomask the areas which are exposed become cured thereby hardening them and rendering them water insoluble the areas which are not exposed remain water soluble development is preferably with a water spray which removes the unexposed areas the screen is then dried blocked out and prepared for printing as is known to those skilled in the art the inks used may be either water based solvent based or plastisols the following examples are illustrative of the invention which is understood not to be limited thereto in a jacketed three neck round bottom flask equipped with an overhead mechanical stirrer and a thermometer is prepared 95 phosphoric acid by mixing 270 g of 85 phosphoric acid and 270 g of 105 phosphoric acid the contents are heated to 50 u00b0 c using a variable temperature water circulating bath attached to the jacketed flask and thoroughly stirred until homogeneous upon cooling to 25 u00b0 c 30 u00b0 c 426 g as 100 of 4 diazonium diphenyl amine chloride is added and stirred for 1 hour to insure complete dissolution the entire reaction is protected from light to the stirring solution at 25 u00b0 c 30 u00b0 c are added 61 g of paraformaldehyde and the temperature is raised to 40 u00b0 c where the mixture was.