Edible Film Developers

Alan Johnson · Jun 5, 2016

The formula of the developing agent in sugars is that of the enediol.Like ascorbic acid it is a reductone.It seems likely that gluconic acid is an oxidation product made by the development.
http://cms.cerritos.edu/uploads/lwaldman/212Lecture/Notes/212LecNotes29Smonosacrxns1.pdf
http://www.srmuniv.ac.in/sites/default/files/files/B1_CHEMISTRYOFCARBOHYDRATES.pdf

DarkroomExperimente · Jun 5, 2016

NedL said:
DE - to recap, you have heated dextrose/glucose, fructose, and honey, with sodium carbonate, and made developers. For sucrose, you heated it with vinegar... and after that did you add an alkali?

with the sucrose I heated it with vinegar to split it into glucose & fructose ...then added sodium carbonate & heated it again to create the developer

DarkroomExperimente · Jun 5, 2016

Alan Johnson said:
The formula of the developing agent in sugars is that of the enediol.Like ascorbic acid it is a reductone.It seems likely that gluconic acid is an oxidation product made by the development.
http://cms.cerritos.edu/uploads/lwaldman/212Lecture/Notes/212LecNotes29Smonosacrxns1.pdf
http://www.srmuniv.ac.in/sites/default/files/files/B1_CHEMISTRYOFCARBOHYDRATES.pdf

thanks those are great links

I'm becoming curious what would happen if I used ammonia instead of sodium carbonate.....would have to heat it outside so I don't fill the house with nasty ammonia fumes

removed account4 · Jun 5, 2016

DarkroomExperimente said:
would have to heat it outside so I don't fill the house with nasty ammonia fumes

carful ..
when i roast coffee in my driveway ( for caffneol ) the police and fire trucks sometimes drive by
cause neighbors smell some sort of smell they aren't used to, and see smoke ... and call them ..
ammonia is even more foul a smell than coffee ... ( and you are in DC )

did you ever do your reversal/shallot experiment with musir ? persian shallots are a different species than regular ones found in an american grocery store ..
kind of pricy, shipped dried and sliced, and after your experiment you can take the rest, add it to plain yogurt with some mint and have a tastey snack ( mást'o musir )

Alan Johnson · Jun 5, 2016

This is DE's sugar developer with added phenidone, the dev time only 10 min.
I did not test without phenidone.
Details-Granulated Sugar 2tbs(29.1g),Hydrochloric Acid 10% 20ml, Water to 200ml, heat at boiling 10min,goes yellow. Make up to 600ml, add 1tbs potassium carbonate (20.5g),heat at boiling 10 min, goes brown. Cool to room temp ,add 0.2g phenidone dissolved in isopropanol. pH~8.5.Store in sealed container.
Develop Acros 10m 20C.

DarkroomExperimente · Jun 5, 2016

Alan Johnson said:
View attachment 158384
This is DE's sugar developer with added phenidone, the dev time only 10 min.
I did not test without phenidone.
Details-Granulated Sugar 2tbs(29.1g),Hydrochloric Acid 10% 20ml, Water to 200ml, heat at boiling 10min,goes yellow. Make up to 600ml, add 1tbs potassium carbonate (20.5g),heat at boiling 10 min, goes brown. Cool to room temp ,add 0.2g phenidone dissolved in isopropanol. pH~8.5.Store in sealed container.
Develop Acros 10m 20C.

looks great

I haven't added phenidone yet...so it's great to see your results

did you get much fog? I often get a lot if I don't add KBr....

DarkroomExperimente · Jun 5, 2016

jnanian said:
carful ..
when i roast coffee in my driveway ( for caffneol ) the police and fire trucks sometimes drive by
cause neighbors smell some sort of smell they aren't used to, and see smoke ... and call them ..
ammonia is even more foul a smell than coffee ... ( and you are in DC )

did you ever do your reversal/shallot experiment with musir ? persian shallots are a different species than regular ones found in an american grocery store ..
kind of pricy, shipped dried and sliced, and after your experiment you can take the rest, add it to plain yogurt with some mint and have a tastey snack ( mást'o musir )

my neighbors are used to my experiments....they usually think it's interesting ( one is an engineer )...

I don't think ammonia fumes will be popular - but I doubt I'll try it more than once or twice unless I get some really interesting result

haven't tried the shallots since the first few times...it would be worth exploring to see if I could use it to make a version of a direct positive process

Alan Johnson · Jun 5, 2016

Not much fog. More by luck than judgement my developer had pH ~8.5, much less than usually seen with carbonate.
I only used hydrochloric acid because don't have anything edible like citric acid or acetic acid.

DarkroomExperimente · Jun 5, 2016

Alan Johnson said:
Not much fog. More by luck than judgement my developer had pH ~8.5, much less than usually seen with carbonate.
I only used hydrochloric acid because don't have anything edible like citric acid or acetic acid.

I had been wondering if I was using too much carbonate....I tend to add as much of something as possible since I'm often not sure if an experiment will work at all

now that I know this works...it will be interesting to tweak the recipe -- not something I know that much about (yet)

DarkroomExperimente · Jun 5, 2016

boiled 2 TBSP honey in 250ml ammonia......turned brown just like it does with carbonate

did this outside...no nasty smell....had to get very close to even get a whiff of ammonia

the brew is cooling off...will test later

this turns out to be a great way to destroy a pyrex container....pyrex was resting on an iron frying pan that was heated with a propane torch...I thought the frying pan would protect the pyrex -- but noooo --- luckily all the ammonia-mix leaked into the frying pan so it didn't leak all over the place

Rudeofus · Jun 5, 2016

Are you sure you want Ammonia as the main alkali of your developer? It hasn't been used in developers for a looong time, and quite likely for good reason.

DarkroomExperimente · Jun 5, 2016

http://www.google.com/patents/US2235938

http://www.tandfonline.com/doi/pdf/10.1080/00021369.1966.10858548

Rudeofus said:
Are you sure you want Ammonia as the main alkali of your developer? It hasn't been used in developers for a looong time, and quite likely for good reason.

just trying it because I'm curious to see what will happen.....

DarkroomExperimente · Jun 5, 2016

OK...so the honey-ammonia experiment did not develop the film...<<<ooops...wrong, it worked

it did, however, leave something purple-ish on the emulsion that comes off easily or turned the emulsion itself into soft purple-ish goop that I can wipe of the base

a few links on reacting glucose with ammonia:

http://www.google.com/patents/US2235938

http://www.tandfonline.com/doi/pdf/10.1080/00021369.1966.10858548

http://www.google.com/patents/US2884411

**************UPDATE---it DID develop an image....but so faint I can hardly see it
whatever sediment/gunk that was on the film wipes off easily

Gerald C Koch · Jun 5, 2016

In order to prevent a lot of needless experimental thrashing may I once again remind everyone that the Kendall-Peltz Rule easily predicts what organic compounds will act as developing agents.

DarkroomExperimente · Jun 5, 2016

Rudeofus said:
Are you sure you want Ammonia as the main alkali of your developer? It hasn't been used in developers for a looong time, and quite likely for good reason.

It looks like not working & turning the film into purple goop is that "good reason" you mentioned

Gerald C Koch said:
In order to prevent a lot of needless experimental thrashing may I once again remind everyone that the Kendall-Peltz Rule easily predicts what organic compounds will act as developing agents.

yes, but some of that thrashing is fun.......but of course you're right I need to learn how to apply the K-P rule...not sure I fully understand it yet

DarkroomExperimente · Jun 5, 2016

just did another test...

instead of always using fresh honey developer...this time I mixed some up and let it sit for 2 days to see if it lasts at all

so...I made a mix similar to what Alan tested:

250ml of the usual honey developer ( 4 TBSP honey, 3 TBSP sodium carbonate in 500 ml water then heated )
added 100ml water, 150 ml 91% isopropyl alcohol with 0.25 g phenidone

Tri-X @ 68F for 10 minutes

negatives look good!

I'm kind of amazed that I started this adventure with success defined as "anything that vaguely resembles an image"....and now I'm getting negatives that look perfectly normal

Alan Johnson · Jun 5, 2016

A lot of phenidone, DE.Until someone runs tests on the development by phenidone alone I would suggest Phenidone concentrations not too different from Gainer's PC Borax, post 44:
(there was a url link here which no longer exists)

DarkroomExperimente · Jun 5, 2016

Alan Johnson said:
A lot of phenidone, DE.Until someone runs tests on the development by phenidone alone I would suggest Phenidone concentrations not too different from Gainer's PC Borax, post 44:
(there was a url link here which no longer exists)

that was an error in my post....I used 0.25 grams not 2.5

was shooting for 0.2 ...but went over and didn't want to scoop out the excess

Gerald C Koch · Jun 5, 2016

When used alone phenidone is a very weak developing agent that produces a low contrast image. The POTA developer is an example of phenidone used alone. To produce a negative of normal contrast and density you need the phenidone to be super-additive with some other developing agent like ascorbic acid or hydroquinone.

DarkroomExperimente · Jun 5, 2016

Gerald C Koch said:
When used alone phenidone is a very weak developing agent that produces a low contrast image. The POTA developer is an example of phenidone used alone. To produce a negative of normal contrast and density you need the phenidone to be super-additive with some other developing agent like ascorbic acid or hydroquinone.

Thanks ....I read somewhere that Technidol used phenidone only to get the normal contrast images from Tech Pan -- do you know if that is correct?

do you know if phenidone is superadditive with caffeic acid? one of the sources I was reading gave me the impression that this process of heating sugars with carbonates generates caffeic acid -- among other things

DarkroomExperimente · Jun 5, 2016

Alan Johnson said:
A lot of phenidone, DE.Until someone runs tests on the development by phenidone alone I would suggest Phenidone concentrations not too different from Gainer's PC Borax, post 44:
(there was a url link here which no longer exists)

that's a fascinating thread...read a lot of it thanks for posting it

Gerald C Koch · Jun 5, 2016

The Kendall-Peltz Rule merely codifies what has been observed empirically. It is not a scientific Law and as such presents no explanation for what is observed. In order for an organic chemical to be a developing agent it must contain at least two groups form the following. Either two hydroxyl groups OH-, two amine groups NH2- or one from each of the two groups. The two groups must be joined by either a double bond or by a backbone of alternating double and single bonds. The groups must be situated on carbon atoms associated with a double bond. The amine groups can be substituted for as in metol. The addition by Peltz extends the definition to include hetero chains containing nitrogen in place of one or more carbons. This was added to explain the developing action of phenidone.

So catechol (1,2-dihydroxybenzene) and hydroquinone (1,4-dihydroxybenzene) are developing agents but resorcinol (1,3-dihydroxybenzene) is not.

DarkroomExperimente · Jun 5, 2016

Gerald C Koch said:
The Kendall-Peltz Rule merely codifies what has been observed empirically. It is not a scientific Law and as such presents no explanation for what is observed. In order for an organic chemical to be a developing agent it must contain at least two groups form the following. Either two hydroxyl groups OH-, two amine groups NH2- or one from each of the two groups. The two groups must be joined by either a double bond or by a backbone of alternating double and single bonds. The amine groups can be substituted for as in metol. The addition by Peltz extends the definition to include hetero chains containing nitrogen in place of one or more carbons. This was added to explain the developing action of phenidone.

So catechol (1,2-dihydroxybenzene) and hydroquinone (1,4-dihydroxybenzene) are developing agents but resorcinol (1,3-dihydroxybenzene) is not.

so catechol has a single double bond between the -OH groups = developer

hydroquinone has several alternating double/single bonds = developer

resorcinol has one single bond, one double bond = not a developer

metol = structure similar to hydroquinone = developer

caffeic acid has one double bond between -OH groups = developer

DarkroomExperimente · Jun 6, 2016

ok...let's see if I understand it now....so Caffeic acid is a developer...

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

looking at its isomers...

2,5-Dihydroxycinnamic acid would be a developer..

https://en.wikipedia.org/wiki/2,5-Dihydroxycinnamic_acid

but

umbellic acid and 2,3-Dihydroxycinnamic acid would not be

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

https://en.wikipedia.org/wiki/2,3-Dihydroxycinnamic_acid

Gerald C Koch · Jun 6, 2016

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

Edible Film Developers

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