Complex salt diazotype photoprinting materials

Claim 1

A PROCESS FOR GRAPHICALLY REPRODUCING AN ORIGINAL WHICH COMPRISES: PLACING THE ORIGINAL TO BE REPRODUCED IN SUPERIMPOSED RELATIONSHIP WITH A SUPPORTED LAYER OF A VISIBLY HEAT-SENSITIVE COMPOSITION, SAID COMPOSITION COMPRISING THE COMPLES SALT REACTION PRODUCT OF A DIAZONIUM SALT AND A COUPLING ATOMATIC SULFONIC ACID, AN ACID STABILIZER, SAID STABILIZER BEING FREE OF AZO COUPLDING GROUPS, AND AN ORGANIC NITROGEN BASE WHICH PRODUCES AN ALKALINE REACTION WHEN HEATED, IRRADIATING SAID SUPERIMPOSED ORIGINAL TO RENDER THE DIAZO COMPOUND INCAPABLE OF COUPLING IN THE AREAS NOT PROTECTED BY THE CARACTERS OF SAID ORIGINAL, AND THEREAFTER HEATING SAID SUPPORTED LAYER OF SAID VISIBLY HEAT-SENSITVE COMPOSITION WHEREBY SAID COMPLEX SALT UNDERGOES AN INTRAMOLECULAR REARRANGEMENT TO FORM AN AZO DYE, AND WHEREBY SAID ORIGINAL IS VISIBLY REPRODUCED.