Ilford Washaid diluted, how long does it keep?

[sandermarijn]

I've recently started using Washaid with my FB prints, in order to cut down on the rinsing. It gives me a bad feeling to waste so much high quality tap water on a print.

In their fact sheet, Ilford Harman state a "working strength" of the 1+4 dilution of 7 days. I suppose this is the time the mixture will last when kept in a closed bottle with no air. It seems awfully short to me.

Does anybody know if one can cheat and use it for longer? Does the stuff decay because it reacts with oxygen or does it degrade regardless of that (because of a possible reaction with the water or something in it)?

I don't print very regularly, once every three weeks maybe. So if the Ilford-given keeping period is strict and correct, then I may better stop using it and rinse my paper longer with plain water instead, just like I used to.

Anybody have experience with keeping Washaid? Any info is much appreciated, thanks.

 

[Anon Ymous]

Or you can buy some sodium sulfite and dissolve 20g of it in 1l of water. You'll toss it after it's used, it doesn't keep well once in solution.

 

[sandermarijn]

Thanks for that suggestion. However, I prefer not to mingle with 'raw' chemicals myself. I also would not know where to get sodium sulfite here in the Netherlands. On the other hand, if Washaid proves to be as unpractical as I suspect (short keeping time) then I may go look for the sodium sulfite solution and evaluate the risks of handling.

 

[Anon Ymous]

...and evaluate the risks of handling.

Well, it's quite benign stuff. AFAIK, it's not even listed as irritant (Xi). Your dish detergent probably is.

 

[Ian Grant]

As others have said you'll have far worse chemicals in your kitchen & bathroom, Sulphite's not a chemical to worry about when it comes to handling. It's used as a food preservative.

Ian

 

[sandermarijn]

Food preservatives should not burn my skin off, I agree. But before becoming my own chemist, does anybody have experience with the keepability of Washaid in particular? Or is everybody rinsing with water only, like I have done for years?