If we abstact of the nuances of formulation, it seems to me that there is nothing supernatural in the HC-110. In my humble opinion, this is a completely ordinary phenidone-hydroquinone developer, concentrated on an anhydrous basis. Its fundamental difference from many other concentrates based on organic base and solvents - is the use of the sulfur complex (IV) of diethanolamine (DEA-SO2) ... Which acts as a source of sulfite ions (apparently not only this function, possibly more - silver solvent and part of pH regulator).
Naturally, this is the main problem in the preparation of such a concentrate at home, since it is not easy to obtain DEA-SO2. But it is quite possible. Bubbling DEA with sulfur dioxide, obtained from sulfite treated with concentrated acid (H2SO4), could probably give an acceptable result.
Naturally, it will be necessary to find out the equivalent ratios of replacing ordinary sodium sulfite with such a DEA complex, but this is apparently a matter of experimentation. As well as the regulation pH of solutions.
Unfortunately, in my country it is quite difficult to obtain DEA for personal experiments (and TEA is not suitable, since it has a much lower ability to form a complex with sulfur dioxide - almost three times) and I can't check these my assumptions.
Unfortunately, I have not seen such information in English. All I could find on this topic was an article in Russian (http://heraldchem.onu.edu.ua/article/download/79510/79461). It contains very indirect data, but it’s at least some “fulcrum” in a further search.Thanks for the informative post. Do you have any references on the solubility of SO2 in DEA and TEA? I am interested in reading more.
Also, I wonder if the solubility of SO2 in TEA might actually be high enough.
The process, in principle, is not so dangerous if carried out at home lab using good ventilation and personal protective equipment. The DEA itself is no more dangerous than the often used TEA. And sulfur dioxide is certainly poisonous, but in high concentrations. If you don't sniff a flask with reagents and do not carry out reactions in a locked toilet room, I think nothing bad will happen. )))I recall that an approximation to the original version of HC110 was published in the film developing cookbook, as mentioned here:
http://www.covingtoninnovations.com/hc110/
The solvent action came from the DEA-sulfur dioxide complex, but making that is an industrial process as DEA is very hazardous.
The only solution is to turn to God to make Sister Olga agree to help me again by translating that document.Unfortunately, I have not seen such information in English. All I could find on this topic was an article in Russian (http://heraldchem.onu.edu.ua/article/download/79510/79461). It contains very indirect data, but it’s at least some “fulcrum” in a further search.
The process, in principle, is not so dangerous if carried out at home lab using good ventilation and personal protective equipment. The DEA itself is no more dangerous than the often used TEA. And sulfur dioxide is certainly poisonous, but in high concentrations. If you don't sniff a flask with reagents and do not carry out reactions in a locked toilet room, I think nothing bad will happen. )))
Naturally, I highly recommend DO NOT doing this without basic chemical protection skills.
"According to UV spectroscopy, complexes of the composition SO2 · Н3-nN (CH2CH2OH) n are realized in ethanol solutions of ethanolamines. The stability constants of these compounds are numerically equal to (2.10 ± 0.30) * 10 ^ -3, (2.34 ± 0.60) * 10 ^ -3 and (0.78 ± 0.13) * 10 ^ -3 for mono-, di- and triethanolamine, respectively. The calculated values of the stability constants are consistent with the pKa of ethanolamines in ethanol"
I believe that is the old version of HC-110.Maybe I’m wrong, but I believe that the data indicated in the MSDS just show the approximate ratio of DEA and sulfur dioxide (that is, the content of sulfur dioxide in the complex).
I believe that is the old version of HC-110.
Here is the link to the new US MSDS:
http://sds.kodakalaris.com/temp/SDS US English - KODAK HC-110 Developer.pdf?t=637217224470487176
In those sources that I managed to find, there are no recommendations on the temperature regime. As I understand it, the adsorption of SO2 and hydrogen sulfide occurs in amines at a natural ambient temperature. This technology is quite widely used in the processing of hydrocarbons, etc. When quarantine ends, I will try to consult with chemical engineers on this issue.IDK at what temperature iminodiethanol (DEA) is reacted with SO2, re safety.
*** - I think - e.g. ethanol, toluene, benzeneSuch a solution can be obtained by passing a small excess of SO2 through a suspended solution of DEA in water, or another solvent***. The excess SO2 is then removed by heating. If the solvent is carefully evaporated (in vacuum) to the end, then you can get a free complex, however, being 1: 1, it does not have a crystalline form, but is a yellow oily liquid.
.....But I don't see a fundamental difference. Base is the same - three developing agents, the organic forms of sulfite and bromide, plus additives...
The research study is in the library of the University of Odessa, Ukraine ,, (Faculty of Physical Chemistry),In addition to the general cognitive value of this article, only one paragraph is of interest (p. 16, last paragraph), which refers to the stability constants of complexes with sulfur dioxide in ethanol solutions of ethanolamines. And there is a link to interesting material on this issue (article in a Ukrainian magazine), but, unfortunately, I have not been able to find it in the public domain so far. Perhaps for this I'll have to make a separate order in the technical libraries of Ukraine, since the article is in Ukrainian (I understand this language a little).
I don't see anything there that would produce the "syrup" consistency of HC-110. I've been a user of this Kodak elixir for many years, and believe me, i wish the formula were public, because Kodak can change it without warning, and someday they may even quit making it entirely.
Fortunately, I can still make D-23, D-72, and D-76 from ingredients (and the replenishers for D-23 and D-76), and if I want long-lasting syrup, I can go dig up the formula for PC-TEA -- Phenidone, Vitamin C, and triethanolamine, just those three ingredients. Most of the time, though, for film I'll just use Parodinal (made from acetaminophen, aka paracetamol) -- if I can find lye again locally.
AFAIK, the syrupy appearance of HC-110 is due to the presence of polyvinylpyrrolidone, which can be sometimes found as a jellylike precipitate at the bottom of old HC-110 packages.
NO, they make shingles for houses these days.Hmm. General Aniline and Film Corporation -- GAF, right? Didn't they fold a while back?
.
Hmm. General Aniline and Film Corporation -- GAF, right? Didn't they fold a while back?
I wouldn't think a quarter gram per liter of anything could do so, however.
Does anyone know how long the shelf life of unopened HC-110 is? Thank you.
True - for the old stuff.decades
True - for the old stuff.
As for the brand new, recently revised, manufacture has been moved back to the USA version - the answer is unclear, but probably not nearly as long.
Yes - see bill troop's post (yes, that bill troop) from August 14, 2019 - it shows as post #26 in the thread for me.is there any reason in the formula change to expect much shorter life?
Yes - see bill troop's post (yes, that bill troop) from August 14, 2019 - it shows as post #26 in the thread for me.
EDIT: Photo Engineer (Ron Mowrey) posted something similar about eleven posts later.
Why is Ilford nearly double the cost of kodak?
And also might just reflect that the Kodak product is once again manufactured in the USA while the Ilford product is manufactured in Germany (I think).I'm a simple man of humble origin. I confess, I do not know.
Adam Smith would tell us that it has something to do with supply and demand.
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