i confused you and mdm and thought the whole initial part of the thread was about the kiwocol 225 sensitizer (which was proven as working later on).
did you do another try with the speedball after the first? i couldn't find anything.
you've received it, but not printed yet? great, please post results.--2 possible sources for "Hardener #3" (Diazidostilbene Sodium Sulfonate, or 4,4'-Diazidostilbene-2,2'-disulfonic Acid Disodium Salt, CAS: 2718-90-3) are identified here.
--I mention having ordered samples of Diazidostilbene Sodium Sulfonate here. Though I have not had an opportunity to test it, yet.
I have not been able to track down the CAS# of the ND22 sensitizer identified on the B&S board, from PJS Chemical. But I have received a sample of a close chemical cousin, 4-Diazodiphenylamine/formaldehyde condensate hydrogen sulfate zinc chloride complex (CAS 68988-17-0), also not tested yet.
i'm ordering from europe, so those two sources most likely won't work for me. pjs might though. when the stuff has been proven usable, i'll try and locate some around here.
speaking of which, has someone thought about contacting a screen printing supplyer with the patent informantion on "hardener no.3" and if they could say which one of their sensitizing solutions is closest to that formula? the same with pjs.
i could try and email kiwo, since they are a german company, afaik.