Bad pyrocatechin from the Formulary?

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aldevo

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I recently purchased 100g of pyrocatechin with which to mix Gainer's Cat-P-TEA recipe.

Opening the container I noted that the pyrocatechin seemed composed of many small off-white colored granules along with many much larger 3- or 4-sided flat leaflets. The container gave off an acrid odor. Not familiar with the physical properties of pyrocatechin I just went ahead and mixed the developer.

It hasn't worked well. Even developing 400TX negs in 135 to 13.5 minutes at 70 degrees is resulting in very flat negatives with no evidence of stain. I'm using Formulary TF-4 for fixing and no hypo clear or sulfite after bath. I rinse for 25 minutes after in water with a tested PH of about 6.5 or slightly higher.

Is the pyrcatechol indeed bad or is it something in my process?

Thanks.
 

Dave Wooten

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First talk to Bud. You are in luck!

The Formulary is legendary for high quality products and excellent service. :smile:
 

JLP

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May have the same bad Pyrocatechol from formulary. Received it about a week ago, also a 100 gram bottle.
I have not yet broken the seal but can tell that there is a lot of granules in darker colors.
Will contact Formulary tomorrow monday
 

sanking

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aldevo said:
I recently purchased 100g of pyrocatechin with which to mix Gainer's Cat-P-TEA recipe.

Opening the container I noted that the pyrocatechin seemed composed of many small off-white colored granules along with many much larger 3- or 4-sided flat leaflets. The container gave off an acrid odor. Not familiar with the physical properties of pyrocatechin I just went ahead and mixed the developer.

It hasn't worked well. Even developing 400TX negs in 135 to 13.5 minutes at 70 degrees is resulting in very flat negatives with no evidence of stain. I'm using Formulary TF-4 for fixing and no hypo clear or sulfite after bath. I rinse for 25 minutes after in water with a tested PH of about 6.5 or slightly higher.

Is the pyrcatechol indeed bad or is it something in my process?

Thanks.

Before you conclude that the pyrocatechin is bad you might want to mix up a 20% solution of sodium carbonate or a 10% solution of sodium hydroxide (same as Red Devil Lye) and make a working solution by mixing one part of your cat-p-tea with 5 parts of the sodium carbonate solution (or 1 part of the sodium hydroxide solution) plus 100 parts of water and try the test again.

In my experience the cat-p-tea is a very slow working formula. The working pH of TEA when mixed with water is somewhere between 9.2- 9.6. Pyrocatechin needs a higher pH to be very active, and I suspect this is the probem you are having, not bad pyrocatechin .

Sandy
 
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aldevo

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Sandy,

Interesting. As when testing any new developer, though, I developed three rolls using a test subject under controlled lighting. The developer temperature across all 3 tests was within 0.5 degrees.

Increasing development time from 10.5 to 12 to 13.5 minutes had little effect on overall negative contrast. The EI was 250 and the negatives appear to have satisfactory shadow detail.

Again, they are just very, very flat.
 

Photo Engineer

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To reiterate and expand on what has been said:

1. If it is bad, the Formulary will replace it.

2. Low pH is often a problem, and cannot be fixed merely by developing longer. It is a fundamental fault in the developer.

PE
 

sanking

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aldevo said:
Increasing development time from 10.5 to 12 to 13.5 minutes had little effect on overall negative contrast. The EI was 250 and the negatives appear to have satisfactory shadow detail.

Again, they are just very, very flat.

And this is exactly what I would expect from a developer based on pyrocateechin working at the pH that TEA provides. The threshold of development of pyrocatechin is on the order of pH 9.5. TEA mixed in water barely reaches the threshold pH, or may actually fall below it.

If there is another reducer involved in the equation the threshold of the primary reducer may be lowered, but I don't believe that is the case with pyrocatechin and phenidone. I experimented with pyrocatehin in TEA and got the same low contrast you are experiencing so my feeling is that mixing in TEA is simply not a viable option with this reducer. On the other hand, if you substitute hydroquinone in the formula you will get a much more active developer, in spite of the fact that the threshold of activity of hydroquinone at a pH of 10.0 is every higher than that of pyrocatechin.

Sandy
 

gainer

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The pH of TEA solutions is not always so predictable. The Commercial is higher in general than the 99% due to the DEA present in the Commercial. In either one, pH varies with concentration. If I can figure out how to do it, I will post the chart from Dow. 99% TEA reaches pH of 10 at about 3% solution by weight. That would be in the neighborhood of 25 ml of TEA per liter of solution if nothing else in the solution lowers pH.

Two other ploys you might use:

1. treat the Cat-P-TEA as if it were Pyrocat HD and experiment with the proportions of A, B and water.

2. add a bit of ascorbic acid to the stock. First, neutralize 4 grams of ascorbic acid with 3 ml of TEA and 5 ml of hot water. Stir it well, let it sit a while and add it to a liter of Cat-P-TEA.

A problem with single solution developers is that the results of varying dilution are not always what one might expect because of the way pH varies with dilution.
 

gainer

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By 99% I meant TEA of 99% purity. The Commercial grade will contain some DEA which is of considerably higher pH in solution. If you can get DEA, you could use it as the solvent. It is not as safe as TEA, but is still used in detergents. Don't mess with MEA.
 

gainer

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Me again.
Hydroquinone is also a staining developer when substituted for catecechol in this formula.

I can't imagine why there was no evidence of stain in your mixture. Did the working solution turn color after standing a while?
 

Gerald Koch

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Catechol (aka pyrocatechin) naturally has a strong phenolic odor. Developing agents when they are oxidized are dark brown or black in color. They may also degrade into a tarry substance and not show a definite crystalline structure.
 

WarEaglemtn

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"If it is bad, the Formulary will replace it.

You are better off dealing with Artcraft chemical. My experiences with Formulary are less than positive... and no, they don't like replacing chemistry that is bad. They have more excuses than a HongKong whore.
 

Photo Engineer

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WarEaglemtn said:
"If it is bad, the Formulary will replace it.

You are better off dealing with Artcraft chemical. My experiences with Formulary are less than positive... and no, they don't like replacing chemistry that is bad. They have more excuses than a HongKong whore.

Well, I sure don't find that to be true. We have seen Bud's responses here to queries about bad products.

Artcraft took weeks to answer a telephone message, and then never got back to me with the information I requested.

The Formulary is a full time business with several employees, but Artcraft is (AFAIK) a part time business for one individual.

PE
 

Formulary/Bud Wilson

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WarEaglemtn said:
"If it is bad, the Formulary will replace it.

You are better off dealing with Artcraft chemical. My experiences with Formulary are less than positive... and no, they don't like replacing chemistry that is bad. They have more excuses than a HongKong whore.


Thank you so much for giving me the opportunity and excuse to come on to this forum and get some selfish self promotion for the Formulary.
Mr. WarEagleman whoever you are please come out from behind your Apug name and be recognized. Your comments are not only non-productive and childish but as the APUG membership knows are untrue.
I agree that you should deal with Artcraft Chemical. Mike at Artcraft runs a very quality business and serves a very useful purpose to the photography community. I do believe, without asking Mike @ Artcraft, that you wil probably find that most of the product that both Artcraft and the Formulary sell are coming from the same manufacturers, especially a product like Cathechol.
I prefer that customers who have much experience dealing with "HongKong whores" as you apparantly do, find a more suitable place to do business than with the Formulary. But I caution you to be careful, because I know that Mike @ Artcraft also has some very high integrity and may not want to deal with someone with the apparant experience that you have exhibited here.

I must state again the Formulary's policy about product we sell. If anybody finds anything that we sell unsatisfactory please tell us and we will refund your money. Pretty simple.

As far as the Catechol mentioned in this thread, yes it looks and smells just as described, and this is the way Catechol has looked and smelled for the 28 years the Formulary has been selling it. If anyone can find a more suitable product to mix up the formulas listed on APUG and other sites please advise me and I will try to obtain it.

As far as our customer service goes we cannnot, as everybody knows, please everybody all of the time even though we try. But if WarEagle Mtn and others on this type of site really try hard they will actually help companies, like the long list of Photo related companies no longer with us, go out of business and quit supplying the needed product for analog photography to exist.

So Mr. WarEagleMtn if you have or have had a problem with the Formulary or other company tell us. Come out from behind your APUG name and be recognized. Call me @ 800-922-5255 and I will handle your complaints and problems, I will give you your $$$$ back and send you on your way so you can go visit your Hong Kong friends.

Thanks again for the opportunity to speak on this fine Forum and thanks to APUG for being here and serving a great purpose.

Best Regards
Photographers Formulary
An APUG sponsor
Bud Wilson
 

jim appleyard

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FWIW, I've had good dealing with both companies. I shop Artcraft because he's local and I like to support a neighbor. I shop Formulary because of the selection and out-of-the-ordinary type of product.

I believe Artcraft is a one-man operation and Mike does return phone calls; not always in five minutes, but they are returned and he has gone out of his way to try and find a product for me.

Formulary has been pleasant to deal with. Mistakes? Yes, but very minor ones and easily corrected.

Nobody's perfect, but what counts is the effort.
 

sanking

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Formulary/Bud Wilson said:
I prefer that customers who have much experience dealing with "HongKong whores" as you apparantly do, find a more suitable place to do business than with the Formulary.

As far as the Catechol mentioned in this thread, yes it looks and smells just as described, and this is the way Catechol has looked and smelled for the 28 years the Formulary has been selling it. If anyone can find a more suitable product to mix up the formulas listed on APUG and other sites please advise me and I will try to obtain it.

Best Regards
Photographers Formulary
An APUG sponsor
Bud Wilson

As a general rule I try to limit my contact with folks who have a lot of experience with "Hong Kong whores."

The absurdity of this thread is that in all probability there is absolutely nothing wrong with the catechol. As I have explained, TEA does not provide sufficient pH to drive catechol developers, and I know this from experience, having mixed up and tested the cat-p-tea formula, as well as a number of variations using catechol in TEA. For a fairly good working catechol developer you need to get the pH up to around 10.5 or more, and cat-p-tea formula, diluted 1:50, barely gets the pH to 9.5.

Sandy
 
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Dave Wooten

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It would be nice if the title to this thread could be changed to "Question about Pyrocatechin" or "Pyrocatechin Help!" or something similar...

Putting a question mark at the end of a statement does not eliminate the possible perception of insinuation.

IMHO utmost thought and care should be given before publishing titles or statements that could possibly be misleading, even though unintentional...
 

gainer

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sanking said:
As a general rule I try to limit my contact with folks who have a lot of experience with "Hong Kong whores."

The absurdity of this thread is that in all probability there is absolutely nothing wrong with the catechol. As I have explained, TEA does not provide sufficient pH to drive catechol developers, and I know this from experience, having mixed up and tested the cat-p-tea formula, as well as a number of variations using catechol in TEA. For a fairly good working catechol developer you need to get the pH up to around 10.5 or more, and cat-p-tea formula, diluted 1:50, barely gets the pH to 9.5.

Sandy
I hope there is no misunderstanding. I don't disagree with Sandy's comments. It is possible that the TEA I used in my original experiment had more DEA in it than the 99 % stuff. I know that the synergism between phenidone and ascorbic acid takes place at lower pH, and that a combination of phenidone, ascorbic acid and catechol can work at lower pH than 10 without sulfite. I don't know why, but I have an idea that the autocatalytic nature of the development of silver halide and the fact that the synergism between ascorbic acid and phenidone needs no sulfite has something to do with it. A dilution of 1+25 should bring the pH up to the required level.

Now pyrogallol and TEA is a different story, but not an issue here. The original issue was the purity of a batch of catechol that had a phenolic odor and a non-uniform particle shape. I thought it was allways that way.
 

sanking

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gainer said:
I hope there is no misunderstanding. I don't disagree with Sandy's comments. It is possible that the TEA I used in my original experiment had more DEA in it than the 99 % stuff. I know that the synergism between phenidone and ascorbic acid takes place at lower pH, and that a combination of phenidone, ascorbic acid and catechol can work at lower pH than 10 without sulfite. I don't know why, but I have an idea that the autocatalytic nature of the development of silver halide and the fact that the synergism between ascorbic acid and phenidone needs no sulfite has something to do with it. A dilution of 1+25 should bring the pH up to the required level.

Now pyrogallol and TEA is a different story, but not an issue here. The original issue was the purity of a batch of catechol that had a phenolic odor and a non-uniform particle shape. I thought it was allways that way.


I hope you don't read my comments about pyrocatechol and TEA as critical of your work because that was certainly not my intent. There is no question but that the cat-p-tea works, it is just very slow working. That may not be undesirable for silver printers, but it is no good for my work. It may be that adding ascorbic to the mix would allow a lower pH, but I have not pesonally tried that. However, I still believe that to get good activation from pyrogallol you need to get the pH up to at least 10.5.

My point is that the low contrast described in the original thread should not be seen as unexpected or the result of bad pyrocatechin. To the contrary, the results are entirely consistent with my own experiments with good pyrocatechin and TEA. If you revisist this and get different results let me know as I would be interested in a fast working pyrocatechin based developer mixed in TEA.

Sandy
 
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kunihiko

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It makes sence for me. In my limited experience, cat-p-tea requiers very looong developing time with 1:50 dilution. 1:25 worked fine, but still slower than my liking.
I will try adding some as Sandy suggested above. Thanks for tips.

BTW, I've had good services from Formulary. Thanks Bud.
 

gainer

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sanking said:
I hope you don't read my comments about pyrocatechol and TEA as critical of your work. There is no question but that the cat-p-tea works, it is just very slow working. That may not be undesirable for silver printers, but it is no good for my work. It may be that adding ascorbic to the mix would allow a lower pH, but I have not pesonally tried that. However, I still believe that to get good activation from pyrogallol you need to get the pH up to at least 10.5.

My point is that the low contrast described in the original thread should not be seen as unexpected or the result of bad pyrocatechin. To the contrary, the results are entirely consistent with my own experiments with good pyrocatechin and TEA. If you revisist this and get different results let me know as I would be interested in a fast working pyrocatechin based developer mixed in TEA.

Sandy
I probably would not use the formula I originally proposed except perhaps to try it for stand or minimal agitation. I have come to the conclusion that single solution developers, by and large, have an optimum dilution and not very much latitude for increase in the ratio. I mean that if 1+25 works well, 1+50 may hardly work.

As we have seen with Pyrocat MC, the ascorbic acid-TEA compound used in place of sulfite when glycol is used as solvent seems to work quite well, but I have not tried it with TEA as the activator. Of course, one way to get higher pH in a single solution developer with TEA as solvent and activator is to make the stock weaker in developing agents and use more of it in the working solution. One could easily test the results by using, say, Cat-P-TEA as I proposed it and adding various amounts of TEA to the working solution. The DOW chart shows pH= 9.5 at 0.25 % TEA and 10 at 2.5 % TEA. I think I will still prefer the versatility of the 2 solution stock with glycol as solvent for the developing agents.

My darkroom is currently out of commission because my grandson is doubling its size. I will finally have the luxury of a wet area and a dry area. Maybe I will be able to try my own ideas by the time of my birthday, which all the French celebrate without knowing it.
 

sanking

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gainer said:
I think I will still prefer the versatility of the 2 solution stock with glycol as solvent for the developing agents.

I agree about the two solution stock being more versatile.

But if I could make a one solution Pyrocat-HD I would be able to recommend it to all those folks who forget to add both Stock A and Stock B when making up the working solution, and then blame the developer rather than themselves for the resulting failure.

Sandy
 
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