Anti-oxidants in formulating a lith developer

[Mark Fisher]

I've been trying to formulate a non-formaldhyde developer off and on for about a year. I have something that I can get reasonable shelf life, but I'm not happy with the tray life. It oxidizes too quickly for my liking. Ascorbic acid is out as it is a developer and I suspect will mess up the "lithiness" of my developer. I've seen reference to TEA in some developers, but that seemed to be an alternative solvent to increase shelf life. I found an old reference to using Fructose for color developers. Anyway, before I go on experimenting I thought I'd tap the great chemical minds at APUG. My chemistry background is pretty meager!

Mark

 

[Alan Johnson]

Any reason you cannot use sodium sulfite as in D85 ?

 

[Mark Fisher]

The answer is yes, to a point. I have sodium metabisulfite in the developer currently, but I could up it. You can only go so far before the developer no longer works as a lith developer. I may try upping the sodium metabisufite just to see if I can manage to get acceptable tray life without extending development too much.

 

[Alan Johnson]

The working solution is often pH 10-11
http://dsiliceo.wordpress.com/tag/formula/
With some Hydrion pH paper from ebay you can check that addition of the acidic sodium bisulfite is not causing pH to fall below this.
Others expressed doubts that the acetone variants work.

 

[Bob Carnie]

Thank you for the link I will try some of the formulas that include paraformaldahyde.

QUOTE=Alan Johnson;1608265]The working solution is often pH 10-11
http://dsiliceo.wordpress.com/tag/formula/
With some Hydrion pH paper from ebay you can check that addition of the acidic sodium bisulfite is not causing pH to fall below this.
Others expressed doubts that the acetone variants work.[/QUOTE]

 

[paul_c5x4]

Others expressed doubts that the acetone variants work.

I did some tests a while back on the acetone substitution proposition - (there was a url link here which no longer exists)

If you are wanting to get the pH up to around 11.0, the easiest way is to add sodium (or potassium) hydroxide.

 

[Mark Fisher]

My pH (measured with pH strips) of my final solution is 11. My part B is a saturated potassium carbonate. I haven't monitored the pH in use so that might be something to check. I tried the acetone substitution and found it to not work at all. Perhaps the answer is just more sulfite......I did get some pepper grain with some older papers.

 

[Simonh82]

Please keep us up to date with any developments. I'd love to find a good mix it yourself lith developer that didn't include formaldehyde.