Mixing D-23

[mbdiesel]

If a working stock solution of D-23 is made (using metol and sodium sulfite), how long does it last? I plan on using it 1:1 and if I make 1 liter of stock, how long will the remaining 1/2 liter of stock last?

I realize that the whole point of mixing from power is to have fresh solution every time and not keep it. I am curious as to how long stock solution would last in a tightly capped glass bottle.

Thanx in advance.

[Ken Lee]

D-23 is similar to D-76.

Kodak gives shelf-life for D-76 here (http://www.kodak.com/global/en/professional/support/techPubs/j78/j78.pdf). See page 7.

[evan clarke]

Actually, it's so cheap to make that shelf life isn't really a big issue..Make it, use what you need and pitch the rest..

[jayabbas]

In my experience refrigerating stock solutions will add at least 50 % to the published shelf life times. If you work with any color developers refrigeration benefits their life immensely and of course no oxygen.

[Ken Lee]

Another option is to store your chemistry in wine bottles - or beer bottles that have the same top - and use a small hand-sized vacuum pump to remove the air. Those pumps are fairly inexpensive and come with a few bottle tops that allow the air to be removed.

If you are looking for something with excellent shelf-life, then try HC-110 or Pyrocat HD prepared in Glycol. With those developers, you just dilute the "syrup" to make working solution and toss when done. There is no "stock" solution.

With D-23 1:1, there is no need to mix a stock solution first: just use twice as much water (or 1/2 the Sodium Sulfite and Metol). See the formula here (http://www.kenleegallery.com/html/tech/D-23.php#Preparation).

[Henry Ambrose]

D23 won't last long - I'd say a week or so. I'd mix it fresh every time.

[BradS]

D-23 is similar to D-76.

Kodak gives shelf-life for D-76 here (http://www.kodak.com/global/en/professional/support/techPubs/j78/j78.pdf). See page 7.

except that D-23 has no hydroquinone - which may actually mean that the shelf life of D23 is better than D76.

[BradS]

D23 won't last long - I'd say a week or so. I'd mix it fresh every time.

My experience with D23 strongly contradicts this. I've used D23 for years. My mom used it before me...I remember her mixing it up in the kitchen with teaspoons and tablespoons. Stored tightly capped in the proverbial "cool dry place" D23 lasts months. In a glass bottle with poly cap it'll last six or eight months easily. All that Sodium Sulfite allows it to keep very well.

[Ken Lee]

Excellent - Thanks !!

The more I learn about it, the more I like it !

[Jim Noel]

I mix D-23 every year or so. I use it straight, and sometimes with a part "B" for extended development times.
It basically lasts for a very long time if it is not contaminated with a carbonate or other chemicals.
The way you are planning on using it should present no storage problems. Put it in a glass, not plastic, bottle and stopper it well.

[BetterSense]

In my experience D23 is practically immortal. I used to use it replenished, and would use a batch for at least a year. I kept it in brown glass and PET bottles. I had better luck with the brown glass...the developer didn't die in the PET but the sides would get coated with crud and it looked ugly.

[mbdiesel]

Great info. Thanx to everyone for their responses. Now time to order some chemicals.

Thank you.