Time between mixing and using a fresh batch of XTOL?

[Tom Kershaw]

Any idea of how long to leave XTOL between mixing and using a fresh 5L batch? I've tended to leave the freshly mixed batch for a few hours in the past but not sure how long is sensible. Whereas I'm well aware D-76 should be left overnight before use. I use / will be using distilled water.

Tom

 

[Tom Kershaw]

I thought the activity of D-76 took a while a stabilise. I've not looked at this for a while, so may be incorrect; and should do some more research.

Tom

 

[brian steinberger]

I've heard this rumor about D-76 as well. I have no idea if it's true or not. I use ID-11 and usually let it sit overnight before using.

 

[Truzi]

I've read a few posts where PE said D-76 is quite active when first mixed, and takes a while to settle down. I usually mix it the day before I use it.

I've not yet tried XTOL, so haven't looked into it.

 

[cliveh]

Why would D-76 have to be left overnight other than to allow the mixing temperature to come down? Since XTOL can be mixed at lower temperatures this is even less of a consideration.

I agree completely.

 

[Aron]

Both PE and Ian Grant commented in the past that it's good practice to let D76/ID-11 sit for a day before use. IIRC Ian said it's good practice to let it sit at least until the next morning.

I've found on the 22nd December, 2009 PE wrote the following on APUG in the thread "D-76, pH elevation with storage":

HQ reacts with Oxygen giving Quinone which reacts with Sodium Sulfite giving HQ-Mono Sulfonate and Hydroxide ion which causes the pH to rise slightly. The explanation here is perhaps an oversimplification, but is for you non-chemists. Mees, Mees and James and Haist all discuss this with chemical symbols and the whole detailed agonizing organic chemistry stuff.

This change though, causes a very tiny increase in activity due to the rise in pH but the loss in HQ is what prevents it from being a huge change. Also, the Oxygen dissolved in the water is used up. In the long run, the developer stabilzes and everything is OK. Usually, I let my D-76 sit for 24 hours before use and this damps out the problem.

 

[cliveh]

Both PE and Ian Grant commented in the past that it's good practice to let D76/ID-11 sit for a day before use. IIRC Ian said it's good practice to let it sit at least until the next morning.

I've found on the 22nd December, 2009 PE wrote the following on APUG in the thread "D-76, pH elevation with storage":

When I have mixed D76, I bottle it in air tight containers and use when it has cooled, which may be several days or weeks later. Are you suggesting that when I mix it in a bucket I should leave this for 24 hours before storage to allow contact with air for this oxygen thingy?

 

[Truzi]

I think the reference is to the oxygen that was in already in the water, or introduced by mixing and pouring. Leaving it in an open bucket would give it an unlimited supply of oxygen and cause it to go bad sooner.

I mix it in a plastic milk jug (using half the water). When it dissolves, I add the rest of the water to make the correct solution, mixing more as I go, and cap it air-tight. Then I let it sit at least a day before using.

Once I first use it, I divide the remaining developer into 1-litre pop bottles, filled to the top, and capped air tight.

 

[cliveh]

Cliveh - they are referring to dissolved Oxygen in the water.

Then why would this take 24 hours?

 

[Thomas Bertilsson]

If you use it replenished, it doesn't matter. Just as an alternative.

 

[Aron]

Again, PE (4/8/09):

All HQ developers undergo a tiny change during the first few hours after mixing
due to the consumption of dissolved oxygen and formation of HQMS
(Hydroquinone Monosulfonate). This usually causes an increase and then decrease
in activity depending on how much oxygen was entrained during mixing and how
the mixed developer was stored.

 

[Rafal Lukawiecki]

When I was developing sensitometric film tests, I used both a freshly made up, and a two weeks old XTol. I did not see any discontinuity in the curves, but I have not done a direct comparison, I'm afraid. I'm curious to hear what others think.

 

[Tom Kershaw]

Rafal,

I've not seen much in the way of density variation with XTOL which is one of the reasons I'm inclined towards it. I had too many unpleasant surprises when I previously used Pyrocat-HD a few years ago; partly related to unpredictable responses to oxidation I suspect.

Tom

 

[tkamiya]

I let my developer solution "rest" overnight but the reason I do that is not the oxygen content or the Ph issue. With D76 and XTOL, right after mixing I see some undissolved particles floating around. I do not want them landing on film during processing and causing spots and uneven processing. In few hours, they will completely dissolve. So I mix, decanter into smaller bottles and seal, then 24 hours (or more) later, I use them for processing.

 

[MattKing]

I could be wrong, but I think PE's comments were in reference to using D76 in an environment where high levels of consistency and repeatability are absolutely necessary - such as film testing.

 

[glstr1263]

I have used Xtol right after mixing and it works just fine.

 

[Thomas Bertilsson]

If you're worried about oxygen in the water, just boil it before using it to mix, and be gentle when mixing in the dry powder.