Activator solution rejuvenation

Claim 1

A METHOD OF PHOTOGRAPHIC REPRODUCTION COMPRISING DEVELOPING AN EXPOSED SUBSTANTIALLY NON-HARDENED GELATINO SILVER HALIDE EMULSION LAYER ON A SUPPORT, SAID EMULSION BEING NOT HARDER THAN A GELATIN LAYER CONTAINING 0.7 GRAM OF FORMALDEHYDE PER POUND OF GELATIN FRESHLY COATED, AND CONTAINING A GELATIN TANNING SILVER HALIDE DEVELOPING AGENT AND A SUBSTANTIALLY NON-TANNING SILVER HALIDE DEVELOPING AGENT AND HAVING ON THE REVERSE SIDE OF THE SUPPORT A COATING CONTAINING AT LEAST 0.01 GRAM PER SQUARE FOOT OF LITHIUM HYDROXIDE, BY ACTIVATING THE SILVER HALIDE EMULSION WITH AN ALKALINE ACTIVATING SOLUTION TO OBTAIN A HARDENED GELATIN AND SILVER IMAGE IN THE AREAS OF THE EMULSION LAYER CORRESPONDING TO THE HIGHLIGHTS OF THE SUBJECT AND SUBSTANTIALLY UNHARDENED GELATIN, SILVER AND SILVER HALIDE IN THE AREAS OF THE EMULSION LAYER CORRESPONDING TO THE SHADOWS OF THE SUBJECT, SAID DEVELOPING BEING SUCH AS TO PREVENT ANY SUBSTANTIAL TANNING OF THE EMULSION LAYER IN SAID AREAS CORRESPONDING TO THE SHADOWS OF THE SUBJECT, PLACING A SHEET HAVING AN ABSORBENT SURFACE AGAINST SAID EMULSION LAYER WHILE SAID EMULSION LAYER IS MOIST TO CAUSE ONLY THE SHADOW AREAS OF THE EMULSION LAYER TO TRANSFER ONLY A STRATUM OF SAID SHADOW AREAS OF THE EMULSION LAYER TO SAID SHEET.