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Caffenol active substances

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I’ve been experimenting with Caffenol for a while, mostly using Fompan 400, and gotten pretty good results. I’n curious about what ingredient does what? Say I wanted to make the solution stronger, would I add more of everything, just more coffee? More soda?

Merry Christmas everyone!
 
The coffee and the vitamin C are the developing agents. They should act as a synergetic pair, so combined they are more active than a brew with either of them could be. The soda is the accelerator which raises the pH for the developing agents to be able to transform silver halide salts into metallic silver. To make the brew stronger, you can increase any of these, but:

1: There will likely be an optimum ratio of coffee to vitamin C. Diverging from this ratio will have limited effect, so if the ratio is already optimal, you don't gain much by adding either coffee or vitamin C and you'd have to add both.
2: Since especially the coffee part is a poorly controlled substance chemically speaking, there's likely room for optimizing the coffee:vitamin C ratio provided you have a way of controlling the strength of the coffee part. I.e. always use the same brand/source of coffee at the same strength/brew procedure.
3: Adding soda will increase activity up to a certain point where the pH won't rise anymore. There's a tapering effect to this; adding more soda may initially make a significant difference, which gets less and less as you keep adding soda. A pH meter helps in analyzing what's happening but I assume most the caffenol users don't have one. Once additional soda doesn't make a difference, you could try adding sodium hydroxide (e.g. drain cleaner). At a very high pH you may experience problems with fogging and ultimately emulsion stability issues, although the latter tends to be not so bad with most modern films.

And there's probably more caveats, such as the question which compounds in the coffee are actually the active ingredient, what the optimum pH is for these ingredients in combination with vitamin C, etc.

Merry Christmas and have fun experimenting.
 
Recent discussion:
www.photrio.com

Caffenol's ascorbic acid activity

Even though I search for quite long, I haven't found an explanation for this yet. - Ascorbic acid is NOT superadditive with chlorogenic/caffeic acid; both are in the same group as HQ (from SA point of view). So, ascorbic acid is NOT restoring the other developer agent. They are both working in...
www.photrio.com www.photrio.com
IMO it is not known for sure if, in addition to caffeic acid, coffee might contain another ingredient X which is active in the development process.
Also not known for sure if caffeic acid is regenerated by ascorbate [superadditive].
Finally, ascorbic acid alone [without coffee] is known to be relatively inactive at pH 10 and quite active at pH 13 but not much is known about its activity beween these limits.
May be some kind of project here, but not easy.
 
koraks said:
The coffee and the vitamin C are the developing agents. They should act as a synergetic pair, so combined they are more active than a brew with either of them could be. The soda is the accelerator which raises the pH for the developing agents to be able to transform silver halide salts into metallic silver. To make the brew stronger, you can increase any of these, but:

1: There will likely be an optimum ratio of coffee to vitamin C. Diverging from this ratio will have limited effect, so if the ratio is already optimal, you don't gain much by adding either coffee or vitamin C and you'd have to add both.
2: Since especially the coffee part is a poorly controlled substance chemically speaking, there's likely room for optimizing the coffee:vitamin C ratio provided you have a way of controlling the strength of the coffee part. I.e. always use the same brand/source of coffee at the same strength/brew procedure.
3: Adding soda will increase activity up to a certain point where the pH won't rise anymore. There's a tapering effect to this; adding more soda may initially make a significant difference, which gets less and less as you keep adding soda. A pH meter helps in analyzing what's happening but I assume most the caffenol users don't have one. Once additional soda doesn't make a difference, you could try adding sodium hydroxide (e.g. drain cleaner). At a very high pH you may experience problems with fogging and ultimately emulsion stability issues, although the latter tends to be not so bad with most modern films.

And there's probably more caveats, such as the question which compounds in the coffee are actually the active ingredient, what the optimum pH is for these ingredients in combination with vitamin C, etc.

Merry Christmas and have fun experimenting.
Click to expand...

Alan Johnson said:
Recent discussion:
www.photrio.com

Caffenol's ascorbic acid activity

Even though I search for quite long, I haven't found an explanation for this yet. - Ascorbic acid is NOT superadditive with chlorogenic/caffeic acid; both are in the same group as HQ (from SA point of view). So, ascorbic acid is NOT restoring the other developer agent. They are both working in...
www.photrio.com www.photrio.com
IMO it is not known for sure if, in addition to caffeic acid, coffee might contain another ingredient X which is active in the development process.
Also not known for sure if caffeic acid is regenerated by ascorbate [superadditive].
Finally, ascorbic acid alone [without coffee] is known to be relatively inactive at pH 10 and quite active at pH 13 but not much is known about its activity beween these limits.
May be some kind of project here, but not easy.
Click to expand...
Thank you, great information in both posts. I tried a recipe with more of everything, Anna slightly different proportions. The negatives came out much better.
 
There was a thread here a while back, someone tried pure caffeic acid with soda and found it didn't develop film at all; mixed with ascorbate, there was no more activity than the ascorbate alone. It's not caffeine, either -- pure caffeine was tested, and decaf coffee works the same as regular.
 
Donald Qualls said:
There was a thread here a while back, someone tried pure caffeic acid with soda and found it didn't develop film at all; mixed with ascorbate, there was no more activity than the ascorbate alone. It's not caffeine, either -- pure caffeine was tested, and decaf coffee works the same as regular.
Click to expand...

Yes, I was looking into this, and there are a lot of things in coffee that can develop film. It probably is more than one developing agent. There is gallic acid, tannic acid, quercetin, myricetin, chlorogenic acid, and a bunch of other things that are either known developing agents, or look a lot like a developing agent. Tannic acid and gallic acid were two of the very first developing agents (gallic acid also was heat-treated to form pyrogallol). @Alan Johnson demonstrated that quercetin is a viable developing agent in collaboration with ascorbic acid.

My guess now is that there are a number of active agents in caffenol. All of them are too weak on their own, but with ascorbic acid there to activate development, they are then much more able to reduce silver halides, whether or not they are superadditive. I read in Haist's volume 1 that there is a theory that a certain potential must be overcome to really kick off development and once passed, weaker agents can then participate. I know that the coffee will develop on its own, but just barely.

I was interested in trying out quercetin as a developing agent on its own (it's structure has a part that looks a lot like catechol), and resurrected Alan's thread about it from 2011.
 
What about used coffee grounds? Is there enough mojo left in them?
 
BrianShaw said:
What about used coffee grounds? Is there enough mojo left in them?
Click to expand...

I wouldn't expect much. The ingredients we're after are water soluble, and most of the easily soluble stuff comes out in the first run of brewing.

They apparently are very good for a garden, though.
 
people have boiled potato skins in water, and used that to develop film in place of the instant coffee.
 
From a link posted by @relistan this table shows the ingredients of roasted coffee beans:
link.springer.com

The content of polyphenols in coffee beans as roasting, origin and storage effect - European Food Research and Technology

Coffee, one of the most popular beverages in the world, contains many bioactive compounds. The aim of this study was a comparative evaluation of the content of bioactive compounds in organic and conventional coffee (Coffea arabica) originating from Brazil during 12 months storage. The content of...
link.springer.com link.springer.com
The main component is chlorogenic Acid.
With increasing pH and time in water the chlorogenic Acid=5-CQA breaks down to quinicic acid =QA and caffeic Acid=CA, fig 3, LHS.

Originally I found that caffeic acid was not as active as coffee:
www.photrio.com

Caffeic Acid-fill of beans

Caffeic acid is often mentioned as the possible developing agent in the instant coffee based developer Caffenol: http://caffenol.blogspot.de/2010/03/caffenol-c-m-recipe.html I compared the activity of Caffenol-C-M with that of a similar solution in which the 40g/L instant coffee (Lidl Arabica)...
www.photrio.com www.photrio.com
This may be due to leaving out quinicic acid and possibly other ingredients in @relistan's table.
The main active substances in caffenol would then be caffeic acid and quinicic acid plus minor ingredients from the table, plus ascorbic acid if added.
 
My instant coffee has a pH of about 6 and at this pH the brew would consist mainly of caffeoylquinicic acids [CQAs]:

Quantification of Caffeoylquinic Acids in Coffee Brews by HPLC-DAD

The influence of different brewing conditions on the concentration of the main caffeoylquinic acids (3-caffeoylquinic acid (3-CQA), 4-caffeoylquinic acid (4-CQA), and 5-caffeoylquinic acid (5-CQA)) was investigated. For this purpose, twenty-four coffee brews were extracted and analyzed using...
www.hindawi.com www.hindawi.com
With soda the pH changes to over 10 and they break down [post 13].
Artichoke extract contains mainly CQAs and may be a substitute for the pure CQAs, I did not try it.
 
they have used beer, wine, and i believe coca cola to develop film. The ingredients may not be as good as that potato based one, but people have different taste
 
Alan Johnson said:
From a link posted by @relistan this table shows the ingredients of roasted coffee beans:
link.springer.com

The content of polyphenols in coffee beans as roasting, origin and storage effect - European Food Research and Technology

Coffee, one of the most popular beverages in the world, contains many bioactive compounds. The aim of this study was a comparative evaluation of the content of bioactive compounds in organic and conventional coffee (Coffea arabica) originating from Brazil during 12 months storage. The content of...
link.springer.com link.springer.com
The main component is chlorogenic Acid.
With increasing pH and time in water the chlorogenic Acid=5-CQA breaks down to quinicic acid =QA and caffeic Acid=CA, fig 3, LHS.

Originally I found that caffeic acid was not as active as coffee:
www.photrio.com

Caffeic Acid-fill of beans

Caffeic acid is often mentioned as the possible developing agent in the instant coffee based developer Caffenol: http://caffenol.blogspot.de/2010/03/caffenol-c-m-recipe.html I compared the activity of Caffenol-C-M with that of a similar solution in which the 40g/L instant coffee (Lidl Arabica)...
www.photrio.com www.photrio.com
This may be due to leaving out quinicic acid and possibly other ingredients in @relistan's table.
The main active substances in caffenol would then be caffeic acid and quinicic acid plus minor ingredients from the table, plus ascorbic acid if added.
Click to expand...

Looking at chlorogenic acid, it has two rings. The first ring has a COOH group bonded, which Haist says makes it not a good developing agent. But the other ring is a catechol and probably will develop film reasonably well, from what I can gather from no real experience except books.
 
I wonder if anyone has boiled oak galls to make an 'organic' pyro developer. Will real pyro work better with the all the oak gall's ancillary compounds - like coffee beats caffeic acid.

I was always under the impression that the combination of an acid and a base produced a salt. So it would seem ascorbic acid in a s. carbonate developer formula would turn to sodium ascorbate and CO2 gas. I imagine it is the ascorbate ions that produce developing activity. Table salt has no developing activity, just the opposite, but then I can't see that chlorine ions would develop silver grains.
 
Nicholas Lindan said:
I wonder if anyone has boiled oak galls to make an 'organic' pyro developer. Will real pyro work better with the all the oak gall's ancillary compounds - like coffee beats caffeic acid.

I was always under the impression that the combination of an acid and a base produced a salt. So it would seem ascorbic acid in a s. carbonate developer formula would turn to sodium ascorbate and CO2 gas. I imagine it is the ascorbate ions that produce developing activity. Table salt has no developing activity, just the opposite, but then I can't see that chlorine ions would develop silver grains.
Click to expand...

I remember seeing someone had done this but now I can’t find it so maybe I mis-remember.

You are right about the ascorbate forming in solution. Cl ions are a silver solvent so they can play an active role in development. Micorodol used a fair amount of sodium chloride.
 
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