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DarkroomExperimente said:
It looks like not working & turning the film into purple goop is that "good reason" you mentioned
Click to expand...
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.
 
Gerald C Koch said:
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
Click to expand...


thanks...very interesting
 
Alan Johnson said:
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?
Click to expand...

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
 
Thanks Michael,
It doesn't look to me like Kodak were on to sugars of the type DE has found to be developers. James was an editor of "The Theory of the Photographic Process" of which I have the 3rd edition and I can find no mention of sugar, glucose or fructose in it.
 
DarkroomExperimente said:
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
Click to expand...
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...#v=onepage&q=fructose alkali reaction&f=false
 
michael_r said:
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
Click to expand...

very interesting....

glucose and ascorbic acid seem very similar in this diagram of the structure:
https://riordanclinic.org/research-study/vitamin-c-research-ivc/

still trying to remember...read somewhere about strongly colored red/brown compounds that are generated by heating sugars in alkaline solutions that were developers or seemed like they were
 
Alan Johnson said:
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
Click to expand...

they mention enediols being formed at 20C....and at that temperature I've never noticed any development...so is that because the concentration of enediols was too low? or they exist for such a brief period of time before turning into something else?

At higher temps do we get a much larger amount of enediols, or something totally different?
 
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
 
DarkroomExperimente said:
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
Click to expand...

he heated glucose with KOH at 35-40C for several DAYS...the solution quickly became colored...then eventually became colorless & contained some lactic acid
 
The following article may be of use. Notice that all the equations are written as equilibria. Conversion from one tautomer to another is easy and requires very little energy.

https://en.wikipedia.org/wiki/Enol

Pierre Glafkides Photographic Chemistry Vol 1 contains many examples of developing agents beyond the few usually mentioned. Used copies are usually available for reasonable cost.
 
DarkroomExperimente said:
he heated glucose with KOH at 35-40C for several DAYS...the solution quickly became colored...then eventually became colorless & contained some lactic acid
Click to expand...

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.
 
Gerald C Koch said:
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.
Click to expand...

Thanks......now that adds to the puzzle then....we are doing our reaction with oxygen from the air available to cause trouble, but we're getting a developer anyway

found a patent that uses glucose, but in a different way... http://www.google.com/patents/US2936308

I just tried adding acid to the honey-dev & it did lighten the color more than adding water did....
 
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
 
Photo Engineer said:
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
Click to expand...

Thanks... any idea what we are actually forming? one compound or several?
 
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.
 
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
 
Photo Engineer said:
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
Click to expand...

thanks....your timing is perfect....I was starting to wonder if I should try this with Borax
 
Alan Johnson said:
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.
Click to expand...

have you tried boiling it with baking soda? was the film acros?
 
scheimfluger_77 said:
Ok I can't stand this any longer...
And I'm not reading the entire thread.

WHY!
Click to expand...

if not for threads like this, how would anyone (without an extensive working knowledge of photographic development literature & organic chemistry, ) ever know about the existence of enols, enediols, the KP rule, and all the other fascinating titbits littered about its (currently) 18 pages?
 
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