Thursday, March 24, 2011

Tylenol and ascorbate - a dynamite combination?

SCTk - Soda - asCorbate - Tylenol & Kbr

A pack of Tylenol/Paracet 20 tablets 500mg

This spells out the active ingredient, 500 mg paracetamol, which is 0.5 gram.
Use this as data for mixing your test developer.


Since Michael saved me a lot of work writing up on PCB, iI will start another project and another run of tests here on Ascorbate developers.

This time the focus is on yet another alternativ of getting rid of the coffe, which is not a proper chemical, but an uncontrollable mix of unknowns.....

Michael has shown that Phenidone is a viable alternative, this is at least equal to instant coffe, if not far, far better.

I like to focus on an alternative that is also available in foodstuff stores, unlike Phenidone, namely what is known under the trade name Tylenol in USA.

The active ingredient in Tylenol is Paracetamol which is the same ingredient as used in the well known home-brew replacement for Rodinal, known as Pa-Rodinal.

Tylenol is a well knwon pain-killer sold all over the world under different names and brands, here locally it is most popular and sold as Paracet, and can be found in pharmacies, ordinary food-stores and small kiosks and gas-stations, in short everywhere nearly round the clock.

I have already done a small test, that was a failure - more on that later.

First I want to know if other has any practical experience on this?

Just for testing purposes I would suggest to start here

SCTk- developer :

Soda anh. 35 g
Ascorbic Acid - 10g
Tylenol - 1.5g
Potassium bromide KBr 1g
Water to make 1L

 - Mix the ingredients in the order given and give ascorbic acid ample time to react with the soda as usual.
 - Tylenol tablets contain sugar and tablet-forming stuff, dissolve the tablets in hot water taken from the 1000ml total, and filter out the gore wit an ordinary coffe filter.
 -  The paracetamol will be in the water, make sure to wash out the filter with pure water to get all the paracetamol.
 - Potassium bromide is best added from a 10% solution stock bottle, 10ml containing 1 gram. This volume is counted into the total volume.

Use the same start times as D-76.

This developer should keep nearly as well as D-76 (ascorbic acid/ sodium ascorbate will NOT die in solution, that is a misconception, on the contrary, it will protect the OTHER developer from oxidation and death, consult the immaculate writings of Gainier on this, see Michel's links).
The developing times will have to be extended along the lines of D-76.

I mentioned I did a tentative test, already.
But that failed. However the reason for that was in part due to the fact I tried to add Potassium bisulphate, which seems to have eaten both developing substances, leaving a very, very weak image, and that I tried to recreate a home brew version of Diafine.

I should have known, I should have followed what I always try to teach my wife (doing kitchen service) - NEVER TRY TO DO TWO THINGS AT THE SAME TIME.

Here I changed 3 things : got rid of coffe, used bisulphate and tried to make a two-bath developer, a perfect recipe for disaster.

Stepping back and mixing the ingredients into one mix did not work either, because of the 10X concentration of of potassium bisulphate.....

But I think the mix given above could be a viable alternative, and urge others to try it out, and report back, or report other experiments along these lines, and other mixes as well.

As usual never try out stuff like this with films containing valuable images! this is deep-water, you're-out-there-alone stuff! 



  1. Something I learned is that paracetamol/acetaminophen is not an active developer as it is. You need p-aminophenol ( to make it work. Paracetamol/acetaminophen can be converted to p-aminophenol with sodium hydroxide.

  2. Well, and WHAT converts Paracetamol in a mix with sodiumhydroxide? We have bisodium carbonate here. Both these dissolves in water, comparison :

    NaOH = Na+ OH-
    Na2CO3 = Na+ CO3-

    BUT CO3 reacts with water in what is generally known as carbonization (think siphon, before CO2 gas was available, delivering the same OH- in the water.

    Since we have soda in excess, this works the same, by design....

  3. If yoiu decide you need NaOH, 20 g NaOH will replace the Soda, for the same molarity in solution......

    Little known fact you could change between all the main bases; strong like KOH & NaOH, medium like K2CO3 & Na2CO3 and even Borax which is very veak compared to these.....

    The trick is balancing them!

  4. I think you mean "Tylenol - 15g" not "1.5g". I just tried that recipe with 35 minutes developing at 23ºC and ended up with very weak negatives. The fogged leader went black, but barely any image (not even the edge lettering) is visible. Subsequent posts of yours suggest 15g in 200ml. I think I'll stick to caffenol =)