Non-food Use
Instant coffee is one of the ingredients in "Caffenol-C", a home-made, non-toxic black-and-white photographic developer. The other ingredients in the basic formula are ascorbic acid and anhydrous sodium carbonate; some recipes also include potassium bromide as a fog-reducing agent. The active ingredient appears to be caffeic acid. Initial experiments on Caffenol were performed in 1995 at the Rochester Institute of Technology; addition of ascorbic acid began around 2000, yielding the improved Caffenol-C, which is less likely to stain negatives than the original formulation. Experiments have shown that cheaper, less desirable brands of coffee work better for this application than more expensive brands.
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