Method for improxvlnxg the the photocondug thqe response of dye sensitized zinc ox de

Claim 1

A METHOD FOR IMPROVING THE PHOTOCONDUCTIVE RESPONSE OF ZINC OXIDE PARTICLES BY DYE-SENSITIZATION WITHOUT SUBSTANTIAL COLORATION OF THE SENSITIZED PARTICLES, SAID PARTICLES BEING ADAPTABLE TO ADMIXTURE WITH A LIQUID BINDER FOR THE PREPARATION OF COATED PHOTOSENSITIVE PRINTING MEDIA, WHICH PROCESS COMPRISES CONTACTINGZINC OXIDE PARTICLES, PRIOR TO ADMIXTURE WITH A BINDER, WITH AT LEAST ONE SOLUTION, IN A SOLVENT HAVING A DIELECTRIC CONSTANT GREATER THAN ABOUT 5 MEASURED AT 20*C., OF AT LEAST ONE ADSORBABLE DYE EXTENDING THE SPECTRAL RESPONSE OF SAID ZINC OXIDE PARTICLES INTO THE VISIBLE SPECTRUM AND SELECTED FROM THE GROUP CONSISTING OF ACRIDINE, THIAZINE, PHTHALEIN, CYANINE, AND TRIPHENYLMETHANE DYES, THE CONCENTRATION OF SAID DYE IN SAID SOLUTION BEING BETWEEN ABOUT 10-2 M AND ABOUT 10-5 M, MAINTAINING SAID PARTICLES IN CONTACT WITH SAID SOLUTION FOR AT LEAST 3 HOURS AT A TEMPERATURE BELOW ABOUT 200*C., AND THEN WASHING SAID PARTICLES WITH A WASHING FLUID HAVING A DIELECTRIC CONSTANT GREATER THAN ABOUT 5 MEASURED AT 20*C. TO REMOVE DYE IN EXCESS OF THAT FORMING A SUBSTANTIALLY MONOMOLECULAR LAYER OF DYE MOLECULES ADSORBED ON SAID PARTICLES.

Claim 2

A METHOD FOR IMPROVING THE PHOTOCONDUCTIVE RESPONSE OF ZINC OXIDE PARTICLES BY DYE-SENSITIZATION WITHOUT SUBSTANTIAL COLORATION OF THE SENSITIZED PARTICLES, SAID PARTICLES BEING ADAPTABLE TO ADMIXTURE WITH A LIQUID BINDER FOR THE PREPARATION OF COATED PHOTOSENSITIVE PRINTING MEDIA, WHICH PROCESS COMPRISES CONTACTINGZINC OXIDE PARTICLES, PRIOR TO ADMIXTURE WITH A BINDER, WITH AT LEAST ONE SOLUTION, IN A SOLVENT HAVING A DIELECTRIC CONSTANT GREATER THAN ABOUT 5 MEASURED AT 20*C., OF AT LEAST ONE ADSORBABLE DYE EXTENDING THE SPECTRAL RESPONSE OF SAID ZINC OXIDE PARTICLES INTO THE VISIBLE SPECTRUM AND SELECTED FROM THE GROUP CONSISTING OF ACRIDINE, THIAZINE, PHTHALEIN, CYANINE, AND TRIPHENYLMETHANE DYES, THE CONCENTRATION OF SAID DYE IN SAID SOLUTION BEING BETWEEN ABOUT 10-2 M AND ABOUT 10-5 M, MAINTAINING SAID PARTICLES IN CONTACT WITH SAID SOLUTION FOR AT LEAST 3 HOURS AT A TEMPERATURE BELOW ABOUT 200*C., AND THEN WASHING SAID PARTICLES WITH A WASHING FLUID HAVING A DIELECTRIC CONSTANT GREATER THAN ABOUT 5 MEASURED AT 20*C. TO REMOVE DYE IN EXCESS OF THAT FORMING A SUBSTANTIALLY MONOMOLECULAR LAYER OF DYE MOLECULES ADSORBED ON SAID PARTICLES.