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D-76Ad -- ascorbic acid version of buffered D-76

from Ryuji Suzuki (rsuzuki@rs.cncdsl.com)
Following interests from a few recent threads here, I did a bit of web search for a close analogue of D-76 using ascorbic acid instead of hydroquinone. I found none, because most used phenidone and their base compositions seemed to have adjusted for phenidone. So I did a bit calculation and cut and try. Something to try if you have thought about ascorbic D-76 before the holiday. Metol 2.0g
L-ascorbic acid 5.0g
borax decahydrate 12.0g
sodium sulfite 100g
I used it 1+1 for HP5+ for 11 min at 20C with S.S. tank hand inversion. The neg looks slightly denser than my taste. What I mean is that EKC's packaged D-76 time is a good starting point. Note that this formula uses ascorbic acid, not its sodium salt. That means if you are making this solution for small scale processing or experiment, you can make solution A with all but borax, and B with borax only, and mix 1:1 to make a 1+1 dilution solution. I don't know the keeping property but part A is acidic and should last for a couple of weeks even in a partially filled bottle. You can also play with the amount of part B to mix in. I think 11g to 13g borax per liter is a good range. This developer comes with no marketing hype. I even hesitate to give it a new name so I just added standard EKC suffix for now. Try it if you feel like it and share what you think!
(posted 8228 days ago)

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