PDA

View Full Version : Fixer Concentrate Go Bad?



Michael Kadillak
3-Dec-2017, 16:38
Acquired a few bottles of Ilford Rapid Fixer concentrate that could be 8-10 years old but sealed in the original box. Does it go bad over time?

Thanks!

mbuonocore
3-Dec-2017, 16:54
From the Rapid Fixer datasheet

"Full, unopened bottles of ILFORD RAPID FIXER
concentrate stored in cool conditions, 5–20C
(41–68F), will keep for two years. Once opened
use completely within six months and keep all
bottles tightly sealed until used."

I wouldn't use it!

Mark Sampson
3-Dec-2017, 17:19
Rapid Fixer (and any liquid fixer) fails when the sulfur precipitates out of the solution. This leaves a yellowish sludge in the bottom of the bottle... or inside the tank of your Kreonite roller-transport RA-4 processor. If you see any sludge, the fixer is useless.

Michael Kadillak
3-Dec-2017, 17:42
Rapid Fixer (and any liquid fixer) fails when the sulfur precipitates out of the solution. This leaves a yellowish sludge in the bottom of the bottle... or inside the tank of your Kreonite roller-transport RA-4 processor. If you see any sludge, the fixer is useless.

Thanks!

Makes sense. I will dispose of it.

Mark Sampson
3-Dec-2017, 20:16
I should add that I don't know if that's the case with alkaline fixers like TF-4, which is cloudy in the bottle from new. I've worked with TF-4, but used it up before it could go bad. Still, it's best to be conservative about photo chemistry- it's far cheaper than the film, and the time and effort you spent making pictures.

esearing
4-Dec-2017, 03:00
Give it a try before you throw it away. Mix it 1:4 and insert a piece of film to see if it clears within a few seconds. I have about 1/4 gallon left of 2 year old Ilford Rapid fixer with a half inch of sulfur in the bottom and it still works fine. I just shake it every couple of weeks. It lasts longer than people give credit but may not be optimal as new.

Harold_4074
5-Dec-2017, 19:06
The sulfur precipitation is caused by oxidation of thiosulfate and/or acidity from dissolved carbon dioxide (sulfite is normally present as a preservative). Cheap polyethylene bottles are somewhat permeable to both oxygen and water, whereas glass is an effective barrier to both. Because concentrates are stored with a smaller ratio of container surface to chemical, then tend to keep better; personal experience says that five-year-old fixer concentrate in glass bottles with good caps will still be usable,

If the fixer will clear film in under 30 seconds, you should have no problem using it. Remember, the old rule was "twice the initial time to clear" for fixing, and discard with the clearing time had doubled from the value for fresh solution. It's not a particularly delicate process.

Tin Can
5-Dec-2017, 19:21
Good point Harold, I am going to rebottle to brown glass my fresh TF5. Photographers Formulary says 2 years. I know it lasts longer.

Cor
7-Dec-2017, 04:14
I too have bottles with sludge..it is still usable, but do proper testing as in clearing time for negative, and I use the same dilution for paper (1+4) and test very regularly with those Silver test dip sticks..

Btw I do not use it on film anymore, have fresh stock for that, re printing is less of a hassle (hasn't been needed thusfar..) than re-shooting..

good luck,

Cor

Pere Casals
7-Dec-2017, 07:10
Michael, recently I run out of concentrated fixer but I had a 0.5L unopenned plastic bottle being 22 years old of Ilford Rapid Fixer, it came with a used enlarger I bought. I filtered out the yellowish precipitate, and it worked perfect. I used it until exhausted.

I always fix with lights open, and it take similar time to clear the film that with a fresh product.

IMHO it can be used, if it clears a not developed film end then it works. Anyone heard ever about an outdated fixer damaging a film ? If a fixer does not work just we can fix again...

xkaes
7-Dec-2017, 07:40
This is an important issue. While it's true that chemicals are usually cheaper then film or paper, it's just waste to throw out chemicals that are still functional.

It's easy to test fixer whether using film or paper. With film, as has been suggested, you can test by putting some unexposed film in the fixer -- at whatever dilution you want -- until it clears, but it is better to be more exacting. That way, you can test not only whether the fixer is OK, but how long it needs to be used and at what dilution. And you can and should test for proper fixation with paper -- since difference films and papers exhaust the fixer at different rates. For example, microfilms need much less time in the fixer (or less dilution) than, for example, Kodak 2475 Recording film. So you really should run multiple tests for all your materials.

Here are some simple tests -- I'm surprised these have not been mentioned because they are well known -- that will save you time and money, and should be repeated occasionally -- especially if you re-use your fixer:

Test for proper fixation (the removal of all unexposed silver by the fixer), as follows

A. Fix, wash and dry an unexposed, undeveloped piece of the selected paper using any desired fixer, time and dilution. Normally, it is best to start with the manufacturer's recommended time and dilution rate.
B. On the emulsion side of the paper, apply one drop of Rapid Selenium Toner concentrate.
C. Wait two minutes.
D. Any yellowing indicates residual silver. Increase the amount of time in the fixer (or decrease dilution) and retest until no yellowing is noticeable..

E. Test for exhaustion of the fixer, as follows:
1. Take two oz of the used fixer.
2. Add two drops of test solution such as Hypocheck:
potassium iodide 0.01g
water 0.05ml
F. Shake.
G. Wait two minutes.
H. The solution should be clear. If it displays any milkiness, the fixer is exhausted -- decrease the dilution of the fixer and run the test again using a new piece of paper.
I. If the fixer clears, the test is passed; increase the dilution of the fixer and repeat the test until it fails.

With these simple, cheap tests -- using small pieces of film or paper -- I use a LOT less fixer than I otherwise would.

Pere Casals
7-Dec-2017, 12:00
For example, microfilms need much less time in the fixer (or less dilution)

Well, microfilms, like Adox CMS 20, can be damaged easily by overfixing (highlights kaput)... Adox says it in the datasheet... and of course halide crystals are very small, with very high interface surface, CMS 20 needs 30s to 60s.

CMS 20 is the single film I use that I find it has a critical fixing procedure.

Doremus Scudder
8-Dec-2017, 03:00
While fixation tests like the one xkaes describes using KRST or the analogous test with HT-2 will tell you if you are fixing adequately, they won't tell you whether your fixer has a lot of precipitate in it that can get stuck on the film emulsion and ruin your film. While fixers with some suspended particulates in it will often fix film and paper adequately, they are on the way out. The suspended particles are often too small to be easily filtered out and can not only stick to the emulsion, but, I'm convinced, also cause small areas of density difference sometimes, causing small dots in the emulsion. I'm not sure why this happens, but I've connected it with fixer particulates enough times to be fairly sure that this is the culprit. I use these tests regularly, but now toss my fixer concentrate at the first sign of sulfur particulates in solution.

As for the potassium iodine test solutions, like Hypo-Check: they aren't nearly sensitive enough for use with papers. By the time the test starts showing a positive result, the amount of dissolved silver in the fixer is much more than acceptable for optimal permanence. These might be helpful with film fixer, where a much higher level of dissolved silver is tolerable, but then there's the time-tested clip test, which not only tells you if your fixer is good, but gives you information for determining your fixing time as well.

Best,

Doremus

Pere Casals
8-Dec-2017, 03:38
but then there's the time-tested clip test, which not only tells you if your fixer is good, but gives you information for determining your fixing time as well.


Yes... the clip test is great ! the most useful, really

Anyway, I think, the two stage fixing it is what ensures a perfect job while maximum exploitation of the chemicals, the drawback is an additional tray there.