View Full Version : Shelf life of chemicals
Bruce Pollock
23-Jan-2005, 21:00
One of my main complaints about the way Kodak packages its chemistry these days is that they have eliminated the smaller volumes. I can only get Dektol in a one gallon size and, since I don't do a lot of printing, I end up throwing out half the batch I mixed up.
I'm thinking about going back to mixing my own Dektol and D-76 from scratch in one litre sizes. I used to do this years ago and have scale, etc. I also have a supply of chemicals that are at least 25 years old, such as Hydroquinone, Elon etc.
Here's my question: Would anyone care to hazard a guess about the shelf life of these chemicals? They've been kept cool and dry but I'm wondering if and how age can affect them. Should I toss them and start fresh?
Jay DeFehr
23-Jan-2005, 22:37
Since paper developer is not critical, ie, all that you stand to lose is a few sheets of paper, I'd mix up some of those vintage chemicals and dip some paper into it. I'll bet that they're just fine, but I'm a gambler. Good luck.
Jay
In general, developing agents (hydroquinone, etc.) have shorter shelf lives than the other ingredients. I'd be more conservative with those. Glycin outlasts most agents in solution, but has a shorter self life when dry (which is strange). The alkalis (sodium carbonate, borax, etc.) last a long time, as does the sodium sulfite. I'm not sure about the restrainers/anti fog agents.
If anyone has more detailed information, I'm curious to hear it ... I'll be facing the same issue soon when I unpack some boxes of potions.
Neal Wydra
24-Jan-2005, 07:30
Dear Bruce,
I have mixed partial packages of Dektol in the past without problem. You may see some tonal differences on some fiber based papers. May I suggest Polymax (liquid, mix as you go) rather than dektol for your future purchases.
Neal Wydra
Bruce Barlow
25-Jan-2005, 09:11
I mix up a gallon of Dektol and subdivide it into 16 oz Coke bottles, which I fill completely, and get 7+ bottles. If you're really cheap, fill 8 almost all the way and evenly, and then top off the last ounce with water and get 8 usable servings. I have noticed no ill effect from the slight dilution. My Coke bottles are glass (and now old), but I have stored Ansco 130 in plastic Coke bottles for nearly a year, used some yesterday, and it's lovely. They've improved the plastic in Coke bottles - they used to let the developer oxidize, but I haven't seen evidence of that lately.
I have stored these "individual servings" for at least 6 months. Just pour one into the tray and dilute it with 2 bottles of water and voila! A quart and a half of working solution, which is perfect for my 8x10s.
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions Inc. All rights reserved.