Chemistry Lifetimes?

[zenrhino]

I just ran two reels of film through Ilfosol S that I bought in the middle of November and they both came out blank.

It was the very last of the bottle so Im thinking that maybe the developer expired in concentrate?

I have both a fresh bottle of Ilfosol S and a small bottle of Rodinal (yes, I'll be joining that cult soon! ) so it's not like I need the shots for production, but man is it annoying.

Ilford's site said "4 months in tightly capped half full bottles." Is my hypothesis reasonable or is it more likely an ID-ten-T error?

 

[Tom Hoskinson]

Ilfosol-S has acquired a reputation for suddenly going bad.

According to the Ilfosol-S Material Safety Data Sheets (MSDS),
Ilfosol-S contains two developing agents, Hydroquinone and Sodium Ascorbate:

Sodium Ascorbate is the sodium salt of Ascorbic Acid (aka vitamin C)

Ilfosol-S also contains:
Sodium Sulfite
Sodium Carbonate
Water

According to Ryuji Suzuki, in order to insure a stable long life water based developer, Ascorbate should be protected with Salycilic Acid to prevent deterioration. See Suzuki's DS-10 and DS-12 developers, for example

Another approach that works very well is to dissolve the developing reagents in Triethanolamine (i.e., no water in the developer concentrate). Pat Gainer's PC-TEA is a good example.

Pat Gainer has also successfully combined sodium ascorbate with Rodinal.

 

[rogueish]

Yes it's quite likely the Ilfosol-S gave up the ghost. It says "4 months in tightly capped half full bottles", but when the bottle is less than half full of dev. and more than half full of air, you could measure it's life expectancy in hours. Ok maybe not that bad, but you get the idea. Ilfosol-S is agood dev but I prefer something thats going to last a little bit longer. I ended up tossing the last few cc's as it was starting to change colour.

 

[Neal]

Dear Zenrhino,

I have found that the best way to use Xtol (similar to Ilfosol) is as a one shot. I store it in 500ml and 250ml glass bottles so I seldom have developer exposed to air for more than a couple of weeks.

Neal Wydra

 

[zenrhino]

I ended up tossing the last few cc's as it was starting to change colour.

Gah! And here I was looking at it as I was mixing thinking "Man, that looks more like iodine than Ilfosol."

Live and loin, I guess. =P