Longevity of mixed Kodak HCA solution

[Tom Kershaw]

I've found a half used batch of Kodak HCA mixed June last year. The Kodak documentation gives a working life of 3 months for the concentrated mix from the powdered package. Is this conservative? Obviously no problem to mix up a fresh batch but just curious as to solution life expectancy.

Tom

 

[Xmas]

Even with non acid fix and intermediate water bath my working solution precipitates in a week or so...

 

[Gerald C Koch]

Kodak's values for life expectancy are based on average use and storage. However trying to stretch 3 months to 9 months is a bit of a reach. HCA is cheap, just discard it.

 

[Rudeofus]

I'd get rid of it. The active ingredient (sulfite) oxidizes over time.

The biggest problem is that not only does Sulfate (= the oxidation product of Sulfite) not work as HCA, it actually decreases swelling and thereby increases the necessary wash time. All that happens without any obvious signs.