Richard Knoppow wrote:
----- Original Message ----- From: "BertS" <aasainz@xxxxxxxxxxxxx> To: <pure-silver@xxxxxxxxxxxxx> Sent: Wednesday, May 20, 2009 3:45 PM Subject: [pure-silver] Re: AZO and Benzotriazole for anti-foggingBogdan Karasek wrote:Hello,I want to do some contact printing using AZO paper that has been kept in a fridge for the past ten years. I'll be using it for the first time tomorrow. If there is fogging, how much benzotriazole should I add per liter of Dektol 1:2. The "Darkroom Cookbook" says that Benzotriazole does not dissolve readily in cold water. It says to dissolve in hot water ... 125°F/51.67°C or higher. Should I heat up the water before diluting the Dektol or can the Dektol dilute solution be heated up and then adding the Benzotriazole?Any and all recommendations are welcome. Cheers, BogdanHere is something I found in my archives. Source is Richard Knoppow, of course./quote "Alfred Lorona" <w6wqc@xxxxxxxxxxxxxx> wrote in message news:au3hms$3b4gu$1@xxxxxxxxxxxxxxxxxxxxxxxxxx > > > > Are benzotriazole pills available anywhere? > > > > AFAIK no longer. Kodak put this up as Antifog NO.1 (Antifog No.2 was 6-Nitrobenzimidazole nitrate). Benzotriazole is available as a powder. For use make it into a 0.2% stock solution. At this low concentration it will dissolve in water. For fog suppression of outdated material the stock is added to developer from 20 ml/liter to 40ml/liter for film, and from 50ml/liter to 500 ml/liter for paper. -- --- Richard Knoppow Los Angeles, CA, USA dickburk@xxxxxxxxxxxxx unquote/Thank you Bert, as usual my references are tucked away in boxes. Eventually I must fix this but it takes other people now because of my back.-- Richard Knoppow Los Angeles, CA, USA dickburk@xxxxxxxxxxxxx
My pleasure to be of help. I keep stuff worth holding to in a subdirectory labeled simply "Knoppow." ;-)
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