Life of Amidol

[fhovie]

About 3 weeks ago, I mixed up a liter of Amidol and made about 20 prints, then quickly put it in a plastic bottle and squeezed all the air out of it. I just poured it in a tray and made a print and the blacks are great - the solution is still an amber color (not dark brown) and it seems to have as much life as it did when I put it on the shelf. I had always been under the impression it would self destruct but it seems air is the major player in its demise. I will cork it back and see if I can get even more out of it - since I always feel like I am spending a lot of money to mix it up and I only use it when printing AZO.

 

[buggzz]

are there any products out there to displace the oxygen left in a bottle with something else, maybe nitrogen, that would slow the spoiling of stored stock mix. May a vacuum sealer with a mason jar adapter.

Anyone tried something like these? Results?

 

[VoidoidRamone]

I trick I learned is to spray some canned air into the bottle and cap it quickly and tightly. It has worked nicely for me, although I've never tried anything else (except those bottles that "fold down").
-Grant

 

[rjr]

Ken,

Tetenal sells something like that, "Protectan", but only in Europe. It´s nothing but a Butan/Propan mixture > lighter gas with a higher price tag.

Flush in a bit until you can see the "fog" evaporate, then close the cap.

It works _very_ well.

If you are a smoker, Argon from a welding flask would be a solution. Or glass pearls.

 

[Jim Moore]

Or you can use something like this:

http://www.freestylephoto.biz/sc_prod.php?cat_id=&pid=1469

 

[garysamson]

An inexpensive solution to displacing the air in the container would be to add glass marbles until the Amidol reached the neck of the bottle.

Gary Samson

 

[DeanC]

Have you mentioned this over on the Azo forum? I'd love to hear what Michael and Paula have to say about this.

Dean

 

[David A. Goldfarb]

What I do to get the most out of my amidol is to do my Azo prints at the beginning of the session, and then if I have enlargements to do, I add the requisite amount of KBr and benzotriazole to the tray for prints on enlarging paper.

 

[MurrayMinchin]

Wine bags! You know, the mylar 4 litre bags of wine with the removable brown spigots that come in a cardboard box? After swilling the wine (HICK!) and giving the bag a good washing out, I tip the box on it's back with the bags spigot removed, and with a funnel, pour the developer from the tray into the bag. Pop the spigot back on, open the tap and squeeze the oxygen out of the bag until the developer just reaches the top. No oxygen. No light. Developer lasts forever.

I use a variation of Ansel's factorial development (development time determined by multiplying emergence time by a factor), so I can keep re-using my Metol/Glycin developer again, and again, and again, and again........

Murray

 

[mikewhi]

Or you can use something like this:

http://www.freestylephoto.biz/sc_prod.php?cat_id=&pid=1469

This may sound dumb (but that never stopped me before):

I use these accordion type bottles. The problem I have is that they tend to tip\tilt and never stand up straight when I squeeze the air out. When they do that, the liquid will often leak out of the rim of the cap. So, I end storing these things in some sort of tray to contain the leakage.

Is there some simple trick that I could use? The brand I bought is Falcon. Are these any good or are there otther brands (like the Arist) that won't tip over?

Thanks.

-Mike

 

[gainer]

By now, someone should have tried it. I don't know if amidol is sufficiently soluble in any of the glycols to be useful, but if it is, such a solution should last a long time. The bit of amidol I had oxidized begore I began playing with glycol, and I don't use enough to spend the money on more.

 

[fhovie]

I guess what I was looking for was the true nature of the demise of the Amidol solution. I know that many have reported an almost endless capaicty but that in a tray it goes dead in 24 hours of exposure to air. Here I have denied air but a few hours of exposure and it seems to hold up at least a few weeks which reduces the cost of a tray of developer considerably (per print). The brew I use is this ...

30g Sodium Sulfite
3g Citric Acid
11g Amidol
.2g Potassium Bromide
per liter water

Could I expect even more shelf life? Is it the water that ruins the Amidol?

 

[fhovie]

I only make working solution ... As with all my chemicals, I make up kits once a month or so by pre-weighing dry chemicals into little plastic packets and heat sealing them into little kits so when I need a solution, I grab the scizzors and mix up a fresh solution ready to use. I believe the shelf life of most dry powders is very good. Amidol is the second most expensive chemical I use; Silver Nitrate being the first.

Frank, I think that somebody should make the distinction between stock solution and working solution, so I'll volunteer. A glycol-based stock solution would undoubtedly have a very long shelf life, but once the stock is made into a working solution, we're right back in the same boat, longevity-wise. I think that denying your working solution oxygen is about the best that can be done to extend its useful life, although there might formulaeic tricks that would further that cause. I usually just hang around and wait for the smart guys to figure that kind of stuff out.

Jay

 

[Tom Hoskinson]

I only make working solution ... As with all my chemicals, I make up kits once a month or so by pre-weighing dry chemicals into little plastic packets and heat sealing them into little kits so when I need a solution, I grab the scizzors and mix up a fresh solution ready to use. I believe the shelf life of most dry powders is very good. Amidol is the second most expensive chemical I use; Silver Nitrate being the first.

Yes indeed, the shelf life of dry Amidol is very long (many years according to reports).

My own experiments with Amidol dissolved in Propylene Glycol have been very successful. The advantage I see in this method is that I minimize the safety problems associated with handling dry amidol powder. I mix up enough stock concentrate for several printing sessions at one time under a vented chemical hood.

 

[Bob F.]

If the caps are not liquid tight, then they are not air tight. I cut a disc of neoprene to make a good air-tight seal for the cap when I re-use old chemical containers.

You can buy zillions of glass marbles at your local toy shop cheaply - but be aware, it takes a lot more marbles that you would think! I've had stock ID-11 still 100% OK after 10 months by topping the bottle (reused Ilford MG developer bottle) up with marbles.

I've tried the accordian bottles but you can only compress by about 25% and the necks are quite wide so I'm not sure how well they perform in practice without replacing the air with another gas; besides, I've never been able to get a decent tune out of one...

Cheeers, Bob.