Thats fine thanks.Cyan dyes are usually Napthol or Phenol derivatives. Magentas are usually Parazolone derivatives, and Yellows are usually Pivaloyl or Phenyl acetoyl derivatives. None of these form Azo dyes which are N=N dyes. These form Azo Methine dyes which are N=C dyes.
I don't know the CAS numbers.
PE
That seems to make sense. This would explain why the likes of old eastman movie stock fades to red, the magenta layer is so stable and everything else fades away.I missed this somehow.
Pyrazolones are NEVER used as Cyan or Yellow couplers.
Only the Magenta is now. In years gone by it was another compound which gave very unstable dyes. Nowdays, color paper and some films use new classes of couplers.
Edited to correct very bad error.
PE
That is really strange.Just pushing the PH up, and running the devs all at 6 minutes.
That is really strange.
Would the PH have anything to do with it?
Is it possible that the magenta developer is ruining the other layers somehow?
Thats fine thanks.
Looks like the couplers in the patent are definitely correct then.
The whole idea about Azo dyes was what I read in some blog about Kodachrome, supposedly claiming thats why Kodachrome was so archival.
I dont think there are any CAS numbers for the couplers. They would have been documented in the patents if so, and by the looks only Kodak, would likely have ever made these compounds.
Thats fine thanks.
Looks like the couplers in the patent are definitely correct then.
The whole idea about Azo dyes was what I read in some blog about Kodachrome, supposedly claiming thats why Kodachrome was so archival.
I dont think there are any CAS numbers for the couplers. They would have been documented in the patents if so, and by the looks only Kodak, would likely have ever made these compounds.
A lot of work has gone into providing a CAS number for all known chemicals. So not in the original patent but they exist now. Unlike chemical names each CAS number is unique. CAS 123-30-8 can be called 4-aminophenol OR 4-hydroxyaniline plus a few more. There is most likely a naming convention saying a phenol derivative over an aniline one but it escapes me now.
A common blood pressure medication valsartan has the IUPAC name (S)-3-methyl-2-(N-{[2'-(2H-1,2,3,4-tetrazol-5-yl)biphenyl-4-yl]methyl}pentanamido)butanoic acid. Even fairly small molecules can be a challenge when it comes to names. So you can see the advantages of CAS numbers. BTW if you look at the structure cited below its synthesis was an organic synthesis tour de force.
http://www.chemspider.com/Chemical-Structure.54833.html
Why don't you find out if anybody has any off-the-shelf couplers for yellow and magenta? Some of the expert discussion suggests that such couplers will be soluble enough for inclusion in the color development as Kodachrome development requires.
See what is available on the market. They probably are already prepared for stability.
The question is whether those will work with Kodachrome or not though.Rockland couplers are quite useful for imaging in color.
PE
Why don't you try it and find out for us!
PE
I knew that, I was trying to get NZoomed off his butt and quit giving advice and try to do something himself!
PE
Im sorry if im taken the wrong way on here, I dont want anyone to think im coming across as a know all, im not trying to be.I knew that, I was trying to get NZoomed off his butt and quit giving advice and try to do something himself!
PE
Im sorry if im taken the wrong way on here, I dont want anyone to think im coming across as a know all, im not trying to be.
Anyway, i dont have the resources to attempt processing currently, let alone any spare Kodachrome! Im just trying to do my best to help.
As far as the polytone couplers go, how stable are they? Unless I was mistaken, I believe that you said the couplers quoted here were not very stable and could last, not sure if these were the polytone ones.
Anyway, im in the process of dealing with labs who can prepare the right couplers.
I am also getting in touch with the royal society of chemistry who should be able to assist in registering these chemicals with a CAS number.
I was thinking the same. Exposing under a UV lamp would be a good test, but thats not replicating ideal storage conditions, so I would keep stored in a hot place for extended periods, I know that heat speeds up the breakdown of dyes, and when frozen, it lasts forever.Maybe you could stick one of the test strips under a bright heat lamp or something to test longevity?
Yes, I agree.The Polytoner ones are basically the same as the ones I've been using, though I'm ordering them separately. Cyan and yellow are the SAME couplers, and the magenta is very very close to the one I'm using.
As PE stated they're not going to be stable, I've not had any real longevity tests to tell you just HOW unstable they really are.
Yes, I agree.
Stability is not a big issue to me TBH, as long as the results are typical of what you would expect from Kodachrome, I would be happy enough and then I would scan them at high res.
Its more if people were wanting something archival that i can see the need for stable dyes.
I will keep everyone updated if I can get the chemicals sourced from China.
It appears from looking at the datasheets, that very little is actually needed when mixing a batch, so it should last a long time if I can get a small sample.
I will arrange to have the chemicals sent directly to you if they confirm they can do it.
I also hope to get in touch with Kelvin Kittle as it looks like he still has his K-lab and has been spending time on its restoration. Im unsure if its now operational, but he has not forgotten about it.
If he has it operational, i would like to see it that someone could help him and get the lab running with the right chemistry.
(I cant because i live in New Zealand) but I will do my best to help him and anyone else who wants to get the right couplers.
I wasn't aware that any of the K labs were still in existence, that'd be awesome to get the chemistry to the point we could help him get it up and running again.
AFAIK, all of the chemicals involved in Kodachrome production had CAS numbers. They are just hard to come by.
Many chemicals can form dye with oxidized color developers. It is mainly a matter of hue and stability.
PE
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