Silver halide solution physical developing solution
View Patent ↗A black-and-white silver halide developing solution and a silver halide solution physical developing solution are used in sequence to provide electrically-conductive film elements from conductive film element precursors that contain photosensitive silver halide emulsions on one or both supporting sides of a transparent substrate. The two developing solutions have unique combinations of developing agents and other essential components to provide complete development of imagewise exposed silver halide to form highly electrically-conductive silver metal in predetermined patterns.
1. A silver halide physical developing solution comprising:
(a) a primary developing agent that is a hydroquinone or ascorbic acid or derivative of either, in an amount of at least 0.01 mol/l and up to and including 1 mol/l, and
(c) a silver halide dissolution catalyst in an amount of at least 0.005 mol/l and up to and including 0.05 mol/l, and
the silver halide physical developing solution containing substantially no (b) catalytic developing agent.
2. The silver halide physical developing solution of claim 1 , further comprising an alkali metal sulfite in an amount of at least 0.2 mol/l and up to and including 3 mol/l.
3. The silver halide physical developing solution of claim 1 , further comprising sodium sulfite or potassium sulfite in an amount at least 0.5 mol/l and up to and including 1 mol/l.
4. The silver halide physical developing solution of claim 1 further comprising one or more metal ion complexing agents in a total amount of at least 0.001 mol/l.
5. The silver halide physical developing solution of claim 4 further comprising a calcium or silver metal ion complexing agent as a metal ion complexing agent in a total amount of at least 0.001 mol/l.
6. The silver halide physical developing solution of claim 1 having a pH of at least 8 and up to and including 12.
7. The silver halide physical developing solution of claim 1 , wherein the primary developing agent is hydroquinone or a derivative thereof, and the silver halide dissolution catalyst is sodium thiocyanate or potassium thiocyanate.
8. The silver halide physical developing solution of claim 7 , further comprising a sodium sulfite or potassium sulfite in an amount of at least 0.5 mol/l and up to and including 1 mol/l.