Xtol keeping properties

[Steven Lee]

Much has been said about Xtol and its replenishing here, plenty of good threads are easily searchable. I want to offer a bit more data regarding Xtol keeping properties. I run a fairly well controlled replenished process, with regular control strip checks and adjustments. What I have found was that my replenishment volume (per roll) has been slowly going up as my replenisher was aging.

I still have the 1L of Xtol mixed almost exactly 10 months ago, on March 24, 2023 (today is Jan 27, 2024). It was stored in a tightly capped amber glass bottle within 55-70F. For comparison, I mixed a fresh 5L bag of Xtol from the same manufacturing batch as my 10 month old bottle.

Next, I developed two Ilford control strips using the stock solutions from both bottles: the freshly mixed vs 10 month old, using the Ilford's recommended times of 8:30 at 20C with intermittent agitation using the Heiland inversion processor.

Here are the readings:

Developer	DMax​	HD​	LD​	DMin​	HD-LD​
10 month old	1.32	0.93	0.37	0.29	0.56
Fresh	1.37	0.97	0.37	0.29	0.60

As you can see, my suspicion was proven correct: while Xtol keeps extremely well, its activity goes down over time. I hope this post will be useful for someone in the future.

 

[Corn_Zhou]

Thank you for the data. Do you think extending developing times for replenished Xtol would compensate for the loss in activity?

 

[brbo]

It was stored in a tightly capped amber glass bottle within 55-70F.

So, mixed with distilled water and stored in glass bottle alway full to the brim?

If yes, I should really think about switching to Adox XT-3 1L packages since it normally takes me about 2 years to use up 5L of Xtol. I just finished my last batch mixed 22 months ago. I would say it worked as good as new, but control strips don't lie...

 

[Sirius Glass]

I have been using XTOL and replenished XTOL for over 10 years. Both stock and replenished keep for well over a year [stock for at least 3 years] if it is stored without any air and tightly sealed. Accordion bottles will eventually leak. I use StopLossBags™ to get those times in the second sentence. The StopLossBags allow one to squeeze out the air completely. You can buy the bags at StopLossBags.com. I strongly recommend that you buy their funnel to avoid pouring losses. I use the 1 liter bags myself.

 

[mshchem]

The bigger the "tank" the better it keeps. 3 1/2 gallon tanks used 4 or 5 days a week were the norm back in the HC-110 days. HC-110 came in a pint bottle ready to mix 3 1/2 gallons on dilution "B"

I would expect a 1 liter "tank" to behave outside what Kodak designed and tested these chemicals to accomplish.

Keep a 1 gallon glass jug and report back in a year

 

[Steven Lee]

So, mixed with distilled water and stored in glass bottle always full to the brim?

Yes, distilled water 100% to the brim, as verified by turning the bottle upside down and seeing zero bubbles. Here is the bottle I use. By the way, the density difference of 0.04 is hardly detectable by a naked eye.

Here's me holding two strips of Delta 400 from the same roll, with the same scene, light, exposure, dev temperature and time. The only difference is the age of the developer: