If you should want to use acetaminophen (Tylenol) in place of p-aminophenol, the 5.45 grams of p-aminophenol will be supplied by 7.5 grams of acetaminophen or 15 of the 500 mg tablets. If you use the tablets, crush them to a powder. Add 1/2 teaspoon of ascorbic acid and 1/4 tsp of sodium bicarbonate to 40 ml water, let the effervescence subside and then add the acetaminophen and 4 grams of NaOH or 5.6 grams of KOH. Stir well and let it stand a while. Bring the water up to about 700 ml and add 2 teaspoons of ascorbic acid and 2 tablespoons of borax. Add water to make a liter.
You will probably have to dilute this developer at least 1+4 to make it managable. The best way to dilute these developers is to add more of the ascorbic acid-borax mixture. You can make 4 liters of it with 35 grams of ascorbic acid and 100 grams of borax. This way you need not worry about whether you will have enough of the developing agent in the working solution when you try such outrageous things as stand development for an hour with 1:50 dilution of the working solution. There will be as much of the ascorbate in the diluted solution as in the full strength, and that will ensure that the p-aminophenol or phenidone is continually regenerated. This is a chance to see if the usual statements about starved development and characteristic curves, Mackie lines, etc. are pertinent here.
Last edited by gainer; 08-03-2007 at 06:46 PM. Click to view previous post history.