That purple goop you observed is likely dichroic fog, which is created when too strong a solvent is present during development. Silver halide was dissolved by the Ammonia, then physically developed on your film surface. After your developer could sit for a while, at least some of the Ammonia must have left the alkaline solution, and the problem disappeared with it.It looks like not working & turning the film into purple goop is that "good reason" you mentioned
Half right. The 2,3-dihydroxycinnamic acid is also a developer. Due to what is called resonance the double bonds in the ring can be thought of as switching with single bonds in the diagrams. In the real world the extra electron density is smeared around all the carbons in the benzene ring. In other words all the carbon atoms are identical.
Were getting well away from sophomore organic chemistry. The following may be helpful.
http://chemwiki.ucdavis.edu/Textbook_Maps/Organic_Chemistry_Textbook_Maps/Map:_Organic_Chemistry_With_a_Biological_Emphasis_(Soderberg)/Chapter_02:_Introduction_to_organic_structure_and_bonding_II/Section_3:_Resonance
From post 395, the enediol form of sugars appears to be the developing agent,
This tutorial gives a formula for it on the 3rd page:
http://cms.cerritos.edu/uploads/lwaldman/212Lecture/Notes/212LecNotes29Smonosacrxns1.pdf
Does it fit with the Kendall Pelz rule?
It's a pretty obscure reaction, not much in the literature about the formation or stability of enediols.The enediols from sugar have never been isolated (p50) so the developer will have to be made by heating with alkali, unlike ascorbic acid.that looks promising... does that reaction occur in an unheated solution? the developer(s) here don't seem to form without heat...
I'm also curious about the reactions mentioned in the link in post 394
also what causes the color change? I read a few places about some of the things that cause the color to change but don't remember at the moment
Regarding ene-diols and developing activity, here's a link to that often-referenced James/Kodak patent which includes some general discussion of developing activity of "non-aromatic ene-diol compounds".
https://www.google.com/patents/US2688549
It's a pretty obscure reaction, not much in the literature about the formation or stability of enediols.The enediols from sugar have never been isolated (p50) so the developer will have to be made by heating with alkali, unlike ascorbic acid.
https://books.google.co.uk/books?id=l4NfU7_sAZoC&pg=PA51&lpg=PA51&dq=fructose+alkali+reaction&source=bl&ots=pVSF71Gpnp&sig=zypSgQdeSZDTOq1hgfXB3YKSg1g&hl=en&sa=X&ved=0ahUKEwiar-ub1pPNAhWnDcAKHay9AVQQ6AEIUzAJ#v=onepage&q=fructose alkali reaction&f=false
Ok I can't stand this any longer...
And I'm not reading the entire thread.
WHY!
OK...re-read this link that was posted earlier:
https://books.google.com/books?id=eUw-AQAAMAAJ&pg=PA153&lpg=PA153&dq=heating+glucose+alkali&source=bl&ots=67Q8CVhKKO&sig=s7TQPHdBPo63OQOfZjAZjqZ4S98&hl=en&sa=X&ved=0ahUKEwjv3q3nmI3NAhVUIlIKHXfCB8EQ6AEITTAJ#v=onepage&q=heating glucose alkali&f=false
they discuss heating glucose in a basic solution and ending up with hydrocaffeic acid
at one point they did mention using copper oxide, but it doesn't seem to be required...just that it causes a resin to be created.
kind of amusing -- he was trying to determine if the color of the solution was due to caramelization of the sugar or something else...and he ended up also testing a bottle of Whiskey that he just happened to have in his lab
he also said that after adding acid to the colored sugar/base solution ( after it cooled down ) that the color went away
he heated glucose with KOH at 35-40C for several DAYS...the solution quickly became colored...then eventually became colorless & contained some lactic acid
Glafkides mentions this reaction in his book cited above. The reaction to produce anything of use as a developing agent must be carried out in the absence of oxygen. Reducing agents (developing agents) are easily oxidized. If they weren't then they would not be useful.
In general, this condensation is found to be taking place in many cases of organic polymerization. It was not pursued by Howard James as it was seen to be a dead end. EK researchers hit a wall and went around it with new chemistry.
PE
SLIME: https://en.wikipedia.org/wiki/Slime_(toy)
Borates react with polyols to form a complex goo with lowered capacity for making things alkaline.
The polymerization of enol compounds (see for example aldol condensation), is probably what you end up with if it goes long enough and is not a "clean" reaction. In extremis, it forms tar.
PE
In a test I found that metaborate alkali does not work.Glucose and and sodium metaborate solution heated at boiling, diluted and cooled had pH 8.5-9,but film developed 45m 20C was blank.
Glucose and sodium carbonate heated at boiling, diluted, with the pH later lowered to ~8.5 using baking soda gave a normal looking image on development 45m 20C.
Metaborate failure may be due to the lower pH or complex formation.
Glucose and sodium carbonate without baking soda gives dense fog.
The conclusion is that sodium carbonate followed by baking soda addition gives the best alkali.
Phenidone addition should cut down the development time.
you will have to store this material in a plastic trash can if you want it to work.thanks....your timing is perfect....I was starting to wonder if I should try this with Borax
Ok I can't stand this any longer...
And I'm not reading the entire thread.
WHY!
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