Adostab longevity

[Hal Reiser]

I'm getting back into darkroom work after a six year pause and I came across a partially filled bottle of Adox Adostab wetting agent that had been stored for the past six years in a glass bottle sealed with a stopper that allows most of the air to be evacuated. I have already purchased a new bottle but was I was wondering if this older batch might still be usable after all that time. Any ideas?

 

[Donald Qualls]

I'm not familiar with that specific Adox product, but I wouldn't expect a wetting agent to suffer from aging -- surfactants are much simpler chemicals than developing agents, and in my experience aren't prone to breakdown.

Put a drop in a cup of water. Does it get slightly slippery, and make the water sheet off instead of forming drops? If so, it's still good.

 

[David Allen]

You should be aware that this is a wetting agent with an additive that is similar to Agfa Sistan which was promoted as an image stabilizer. It is meant to be used as a last stage and without any further washing. The old Agfa data sheets warned that a too high concentration can lead to stains which take some time to appear - especially on negatives and this is the reason that I never used it. Please note that my temporary website address is: http://dsallen.carpentier-galerie.de

 

[AgX]

I'm getting back into darkroom work after a six year pause and I came across a partially filled bottle of Adox Adostab wetting agent.

Adostab is NOT a wetting agent and must not be used as such. Though it is a final bath. And bad enough Adox call it a wetting agent in first instance. It is a chemical active compound. Which is a scavenger for free or freed silver-ions preventing them from diffusing to the surface where otherwise these either would turn into silversulfide or metallic silver. For more information look up what has been written on Agfa Sistan. A wrong application of this may harm the image. In contrast to a wetting agent.

 

[AgX]

The old Agfa data sheets warned that a too high concentration can lead to stains which take some time to appear - especially on negatives and this is the reason that I never used it.

Not only a too high concentration of the working solution, if at all. But droplets left on the paper. Then the absulote amount of active compound would be by magnitudes higher than from the plain fluid film left on the paper.
With this in mind there should not be any problems.

Concerning storage, I do nit see any problems. But final word should be by Adox.

 

[lantau]

Unless mold is growing in it I don't see why it wouldn't last indefinitely. I've been using my open bottle since summer 2016, when I made the first darkroom print of my life.

I keep my prints in the working solution for 90s (sometimes I forget it and it turns out to be 5-10 minutes) and then hang them up by a corner. RC as well as FB. Once the emulsion is dry, they come down and go into the RC drying rack or between pages of blotting paper (FB). So far I had no problems with it.

It contains a wetting agent, so that everything will run off when hung to dry. To me that is essential, and colour prints go into a final bath with wetting agent only.