Pyro-TEA developer

Thanks a lot Pat,

Photo Techniques isn't readily available in Holland either. So, I very much appreciate you publishing this here.

Gilbert

Pat you have all my gratitude. The manuscript you published is what, many of us, needed. Thanks also for the comments of others users.
Daniele

Tom Hoskinson said:

In the March/April 2004 edition of Photo Techniques, Pat Gainer published his
CAT-P-TEA formulation:

Triethanolamine------100 ml
Phenidone------------0.2 grams
Pyrocatechol---------10 grams

Heat the triethanolamine to dissolve the phenidone and pyrocatechol.

For use, dilute 1 part CAT-P-TEA with 50 parts of water

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Don't talk about this too loudly in uneducated circles, the name brings up unsavory and quite smelly visions....

Tom Hoskinson said:

In the March/April 2004 edition of Photo Techniques, Pat Gainer published his
CAT-P-TEA formulation:

Triethanolamine------100 ml
Phenidone------------0.2 grams
Pyrocatechol---------10 grams

Heat the triethanolamine to dissolve the phenidone and pyrocatechol.

For use, dilute 1 part CAT-P-TEA with 50 parts of water

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Just one comment. I have not tested the CAT-P-TEA formula but I suspect that at the 1:50 dilution, which would be an approximate equal of regular Pyrocat 1:1:100, developing times would be quite a bit longer with CAT-P-TEA. My thinking on this is that the formula with Triethanolamine will give a a developer with a working pH of about 9.5, much lower than the PH of 10.9 achieved with the Pyrocat-HD formula. Since the threshold of developer activity of pyrocatechin is around pH 9.0, or so I believe from previous research, this would probably result in a much slower working developer.

Again, this is supposition since I have not actually tested the concept. If I am wrong may Neptune rain on me all week.

Sandy

pH will depend on whether you use tech grade or industrial grade. With industrial grade, a 2% solution (by weight) is almost 10.5. That would be about the percentage of a 1+50 dilution since most of the stock is TEA. The major impurity in the industrial grade is diethanolamine.

Search for Dow Chemical. You will find a brochure covering MEA, DEA and TEA. Has more charts than you can shake a stick at.

jdef said:

That's great information, but what is A1?

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OOPS!

Didn't take long enough.

A1 was:

100 ml propylene glycol or glycerine or ethylene glycol
10 g ascorbic or erythorbic acid
0.25 g phenidone

Heat till dissolved.

jdef said:

I've been meaning to try adding a little metol or phenidone to the P-TEA, but I have only gone as far as to mix it 50/50 with the PG/PQ concentrate, which produces an entirely different developer from either of the "parent" developers. Regarding Cat-P-TEA; could one substitute hydroquinone for the catechol?

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Well, I had been meaning to try the Pyro-TEA formula for a while and finally got around to it today. I mixed two separate solutions of the Pyro-TEA formula, which I will call P-TEA and PM-TEA.

P-TEA
TEA, 100ml
Pyrogallol, 10.0 g

PM-TEA
TEA, 100ml
Pyrogallol, 10.0g
Metol, 2.0 g
Bromide, 0.2g

I exposed two sheets of Ilford FP4+ film to a Stouffer step wedge for the same time, then developed one in P-TEA, and a second in PM-TEA for ten minute, using a 1:50 dilution. The pH of the working solution was 9.1. By contrast a working solution of PMK 1:2:100 has a pH of about 8.6, while a working solution of Pyrocat-HD has a pH of about 10.9.

As soon as the processed negatives dried I read the densities in Blue channel and plotted the curves. Then I compared the curves with existing curves of the same film and time of development in PMK and Pyrocat-HD.

Here are my conclusions based on reading of the curves in terms of developer energy, EFS and B+f. I won't comment on grain and sharpness since it is really not possible to evaluate these qualities in step wedge tests.

Developer Energy -- Pyrocat-HD (1.1:100) and PM-TEA (1:50), were almost identical in terms of energy. The step tablet densities at ten minutes of development were almost identical for both developers. PMK 1:2:100 was next in energy, but quite far behind both PM-TEA and Pyrocat-HD.
Regular P-TEA, at 1:50 required the longest development time of all.

EFS -- Comparing curves of all four developers gave the following results. Pyrocat-HD, EFS = 125, PM-TEA and PMK, EFS = 100, and P-TEA 70, EFS = 70.

B+f --Pyrocat-HD and PMK, both log 0.06 in blue channel. PM-TEA, 0.14, and P-TEA, 0.18.

I did not compare curves with UV reading but can note that the color of the stain of PM-TEA and P-TEA is very similar to PMK with film, on the yellowish side, while the Pyrocat-HD stain is distinctly brown.

My conclusion is that P-TEA can be measurably improved in energy and EFS by the addition of metol, and both P-TEA and PM-TEA need some bromide to reduce B+F.

Sandy

Sandy,
How did you get the metol into the TEA? Did it dissolve directly into the TEA? If so, at what temperature did it go into solution?

Tom Hoskinson said:

Sandy,
How did you get the metol into the TEA? Did it dissolve directly into the TEA? If so, at what temperature did it go into solution?

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And excuse me if this question has been answered on some thread in some other forum, but where does one purchase TEA?

Tom Hoskinson said:

Sandy,
How did you get the metol into the TEA? Did it dissolve directly into the TEA? If so, at what temperature did it go into solution?

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Tom,

I poured the pyrogallol (pyrogallol + metol + bromide for the PM-TEA formula) directly into the TEA at about 250 degrees F. Everything dissolved quickly with just a couple of minutes of stirring.

The resulting solutions were a dark purplish/brown in color. The working solutions from both formulas were medium amber in color, just a tad darker than PMK working solutions. But when I discarded the used developer it was very darkish brown, much more so than I have seen with PMK. But the negatives came out ok, albeit with slightly more B+f than I like.

Sandy

clay said:

And excuse me if this question has been answered on some thread in some other forum, but where does one purchase TEA?

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Clay,

http://www.chemistrystore.com/

Great site that I first learned about from Michael Mutmansky.

Sandy

sanking said:

Tom,

I poured the pyrogallol (pyrogallol + metol + bromide for the PM-TEA formula) directly into the TEA at about 250 degrees F. Everything dissolved quickly with just a couple of minutes of stirring.

The resulting solutions were a dark purplish/brown in color. The working solutions from both formulas were medium amber in color, just a tad darker than PMK working solutions. But when I discarded the used developer it was very darkish brown, much more so than I have seen with PMK. But the negatives came out ok, albeit with slightly more B+f than I like.

Sandy

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Thanks very much, Sandy. This is a very useful piece of information.

I had tried dissolving metol in several of the alchohols and glycols without success - but I had not tried it in TEA. I guess it likes the alkalinity provided by TEA.

Your result suggests to me that Glycin may also be soluble in TEA - I'll try it out (Glycin is described as freely soluble in alkaline solutions).

Okay, I mixed up a small batch of CAT-P-TEA, with a little added bromide, and everything went into solution at 220-230 degrees. I tried to mix up some PM-TEA, at the same temperature, and the metol never went into solution. Is there a trick here that I am not privy to?

clay said:

Okay, I mixed up a small batch of CAT-P-TEA, with a little added bromide, and everything went into solution at 220-230 degrees. I tried to mix up some PM-TEA, at the same temperature, and the metol never went into solution. Is there a trick here that I am not privy to?

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You may need to take the TEA to a higher temperature. When I did this the metol went into solution almost immediately but I mixed at a higher temperature. I wrote 250º F but in fact my TEA solution was probably even hoter than that because the temperture was at 250º F and still rising when I quit measuriing. It might have been as high as 280-300º.

Sandy

sanking said:

You may need to take the TEA to a higher temperature. When I did this the metol went into solution almost immediately but I mixed at a higher temperature. I wrote 250º F but in fact my TEA solution was probably even hoter than that because the temperture was at 250º F and still rising when I quit measuriing. It might have been as high as 280-300º.

Sandy

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It's been years since i mixed up PMK, and it just occurred to me: was I supposed to dissolve the metol BEFORE the pyrogallic acid? I seem to remember that the metol is supposed to go in first. I did it the other way....

clay said:

It's been years since i mixed up PMK, and it just occurred to me: was I supposed to dissolve the metol BEFORE the pyrogallic acid? I seem to remember that the metol is supposed to go in first. I did it the other way....

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I had both chemicals in the same container and just poured them in together with stirring. Everything went completely into solution within about two minutes or less.

jdef said:

I've been told that Metol will not dissolve in glycol ( I assumed the same for TEA), and that phenidone is the logical alternative for this application. I guess just about anything will dissolve given a high enough temperature, but I wonder how these high temperatures might affect the working properties of the resulting developers. I have concentrates of P-TEA and PC-TEA on hand, and simply mix the two 50/50 to make what must be a very similar developer to PM-TEA, which I call PCP-TEA. Last night I made up a batch of QP-TEA, and was surprised at the long developing times (20 min. for Ultrafine 125). I expected QP-TEA to be about as active as the PG/PQ developer with sodium carbonate and borax, but apparently it is not. I was also surprised by the very minimal stain compared to the PG/PQ. I haven't printed the QP-TEA negatives yet, so I can't comment further on that developer. The PCP-TEA, however is proving to be a very good staining developer, with activity similar to PC-TEA, and stain similar to P-TEA. Patrick has suggested that a pinch of sulfite might be needed to activate the superadditivity between the Pyrogallol and Phenidone, but I haven't tried that yet. The light looks great outside my window, so maybe I'll go expose a roll or two and try it.

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Hi, my experience with Metol is that even if you go up to 300F, Metol will not dissolve in PG. On the other hand, Sandy and several others have reported success dissolving Metol in TEA at temperatures around 250F.

My experience with PQ-PG (Phenidone/Hydroquinone/Polyethylene Glycol activated with Sodium Carbonate) is that if the dilution is too great, PQ-PG becomes very inactive and increasing the amount of alkali doesn't help much. PQ-PG works ok at 1:1:100, at 1:1:200 its activity drops off a cliff.

I discovered this while making direct comparisons with PC-PG (Phenidone/Pyrocatechol/Polyethylene Glycol activated with Sodium Carbonate). The PC-PG combination retained its activity at much greater dilution levels than the PQ-PG.

I did not use either sulfite or KBr in any of this testing.

Tom,

Part of this problem may be the lack of sulfite in the PQ formulation. Sulfite is necessary to the superadditivity beteen the P and the Q. A very small amount will sufice, but some is necessary. I appears that the formation of hydroquinone monosulfonate is a necessary step in that synergism. OTH, the PC formula does not need sulfite for synergism.

I have not tried 1:1:200 with either one, but I'd be willing to bet that the PQ-Glycol would look more like the PC-Glycol if you added a gram or so of sulfite to the working solution.

I mixed a batch of P-TEA and tried it 1:150 with tubes, minimal agitation (the same way I use Pyrocat-HD). After fixing, when I turned the lights on, the spent developer was the ugliest dark brown-black mess I've ever seen, but the negatives seemed to develop OK. I'm still zeroing in on times, but it looks as though this method of development will work just fine.
juan

juan said:

I mixed a batch of P-TEA and tried it 1:150 with tubes, minimal agitation (the same way I use Pyrocat-HD). After fixing, when I turned the lights on, the spent developer was the ugliest dark brown-black mess I've ever seen, but the negatives seemed to develop OK. I'm still zeroing in on times, but it looks as though this method of development will work just fine.
juan

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I tried minimal agitation development with rollfilm in P-TEA (400TMax) and got unbelievable fog and a great deal of mottling. The negatives are incredibly sharp but I'm not particularly sanguine about how they'll print.

What film did you use?