Homebrew XTOL?

[sanking]

I have been testing the substitution of hydroquinone for catechol in Pyrocat MC. I'm amazed. It is water white clear, and has remained so for several days. It immediately colors up when the carbonate is added, and the stain it produces is not so much different from that of catechol to my eye, but it may be quite different to alternate printing processes. It is a very vigorous developer, about the same as Pyrocat MC, and tanning is quite evident. .

Did you substitute the hydroquinone at the same amount as pyrocatechin?

Sandy

 

[eclarke]

DS-10 is a very good fine grain developer. Usually, fine grain developers cost in terms of loss of speed, sharpness, or both. However, DS-10 affects neither speed nor sharpness, so in this sense, I use DS-10 as my general purpose film developer. One thing to remember is that it shouldn't be used for Pan F Plus, APX 100 and perhaps some other slow films using non tabular grain technology. The result is obvious loss of speed, contrast and density. (It's very obvious so a clip test should tell you.)

I've made several improvements to DS-10, but they are meant to improve image quality with 100+ speed films, and to improve keeping properties. As fixing the above incompatibility issue costs in terms of image quality, I am not sure of incorporating such improvements in the future. (However, I have a new developer that works superbly with those slow conventional films, as well as fast films, with excellent push property, so they are nicely complementary.)

Hi,
Which developer is this one? I also expose some PL25 and this sounds interesting to me..Thanks..Evan

 

[Richard Wasserman]

Evan,

The formula can be found on Ryuji Suzuki's Silvergrain Wiki at:
Dead Link Removed

Richard Wasserman

 

[gainer]

Did you substitute the hydroquinone at the same amount as pyrocatechin?

Sandy

Yes. I figured since the molecular weights are the same, I should use the same amounts.

From what I have read in The Theory----, the color of the dye image is the same as the color of oxidized developing agent. This conclusion was reached by those who had the means and knowledge to do a chemical analysis of both. I don't know how to make a proper comparison by eye. Perhaps there is some way to equalize the effects of concentration, etc. If I leave a cup of most any developer sitting open long enough, I can't see through it.

For some, the color is not as important as it is for others as long as it looks like density to graded paper. I would not make any claims for hydroquinone as a staining developer for any of what we call alternate printing processes. All I can say is that is can stain, and might be a way to do at least a preliminary test of a developer formula without wasting the more expensive catechol. It has some of the other properties of catechol that seem to affect sharpness, such as tanning the gelatin in proportion to the image. I'm thinking of differential refraction at edges due to differential hardening.

 

[sanking]

Yes. I figured since the molecular weights are the same, I should use the same amounts.

From what I have read in The Theory----, the color of the dye image is the same as the color of oxidized developing agent. This conclusion was reached by those who had the means and knowledge to do a chemical analysis of both. I don't know how to make a proper comparison by eye. Perhaps there is some way to equalize the effects of concentration, etc. If I leave a cup of most any developer sitting open long enough, I can't see through it.

For some, the color is not as important as it is for others as long as it looks like density to graded paper. I would not make any claims for hydroquinone as a staining developer for any of what we call alternate printing processes. All I can say is that is can stain, and might be a way to do at least a preliminary test of a developer formula without wasting the more expensive catechol. It has some of the other properties of catechol that seem to affect sharpness, such as tanning the gelatin in proportion to the image. I'm thinking of differential refraction at edges due to differential hardening.

Well, that is very interesting. I made the same substitution, weight for weight, in the Pyrocat-HD formula several years ago and got very unacceptable results. Lots of unwanted B+F when tested same as Pyrocat-HD. The color of the stain was also different, but it was not the color that bothered me but the heavy general stain.

Course, Pyrocat-MC is an entirely different developer from Pyrocat-HD, so I am not shocked at the finding. I will runs some tests of this soon to see how the stain looks in Blue and UV.

Sandy

 

[eclarke]

Hi,
Which developer is this one? I also expose some PL25 and this sounds interesting to me..Thanks..Evan

Thanks Richard,
I have the DS10 and DS12 formulas, I was curious about the new one Ryuji described in the above post..Evan

 

[gainer]

Meanwhile, I may have overstated the amount of water needed to make the PC-TEA soluble at lower temperatures. To neutralize 100 grams of ascorbic acid with TEA and water, 85 grams of TEA (the 99 % type) and only 10.2 grams of water, mixed with 100 grams of ascorbic acid, makes a slurry at room temperature. Warm that and it almost dissolves. It will easily dissolve in warm propylene glycol or TEA. When I say warm, I mean no hotter than hot coffee or chocolate or the kind of tea you could drink. 10.2 grams of water are about 2 teaspoons full. 85 grams of TEA are about 75 ml at room temperature. Phenidone is soluble in either glycol or TEA and may be added at any time. I think I would prefer the PC-Glycol for the flexibility of control allowed by the separate alkali.
If you believe in sulfite, it's easy enough to add it to the working solution. Sulfite has several possible effects, one of which is to reduce tanning action.
Slightly off topic, I read that adjacency effects may be greater when a water stop is used. The idea is that distribution of bromide is more rapidly change by the stop than is developing action. Curious, no?

 

[eclarke]

As Ryuji pointed out, I have been using his DS-2 formula which is very good.and can be mixed in a heartbeat. I have made a couple liters of DS-12 and now some DS-10 (I like this a lot) but need some advice about dissolving the salicylic acid. Can you dissolve it in alchohol like you would Phenidone??..Thanks

 

[eclarke]

As Ryuji pointed out, I have been using his DS-2 formula which is very good.and can be mixed in a heartbeat. I have made a couple liters of DS-12 and now some DS-10 (I like this a lot) but need some advice about dissolving the salicylic acid. Can you dissolve it in alchohol like you would Phenidone??..Thanks..Evan

 

[Alan Johnson]

When I tried DS-12 I made a 5x concentrate of the formula at:
www.silvergrain.org/Photo-Tech/film-dev-recommend.html
The salicylic acid has a solubility in water of 2g/L and dissolved OK.
I used TMX 12m 68F and PanF+ 9m 68F.

 

[eclarke]

Thanks for the input and the times Alan. How did you like the result with PanF?? The salicylic acid dissolved for me but required about 45 minutes with a magnetic stirrer. I am a manufacturer of things and I just always need to make the process more efficient. I like and prefer the results I have gotten with the DS-10 but I really love the DS-2 for it's ability to be mixed instantly. If someone has a shortcut for getting the salicylic acid into solution more quickly, I would love to learn it..Thanks..Evan Clarke

 

[Jordan]

Can you pre-dissolve your salicylic acid in some alcohol? It is much more soluble in alcohol than in water.

 

[gainer]

Salicylic acid is a fungicide used in patent medicines such as Scalpicin and one of Dr. Scholl's remedies for athlete's foot. Scalpicin is 3 %. I don't know about the other. It would be more expensive, I'm sure, but maybe worth it. You could also look at the other ingredients in Scalpicin to find what solvents are used. IIRC, propylene glycol is one of them.

 

[Jordan]

Salicylic acid is also used as an astringent in facial cleansers (think of Neutrogena and other brands aimed at those with acne-prone skin). IIRC these are about 2% salicylic acid (likely with other perfumes, alcohols, surfactants, etc. whose concentrations are much higher than this). Likely not suitable for use in a developer.

 

[eclarke]

Salicylic acid is a fungicide used in patent medicines such as Scalpicin and one of Dr. Scholl's remedies for athlete's foot. Scalpicin is 3 %. I don't know about the other. It would be more expensive, I'm sure, but maybe worth it. You could also look at the other ingredients in Scalpicin to find what solvents are used. IIRC, propylene glycol is one of them.

That's a good idea. I am blessed with a great lab chemical supply here and can really get anything in several purity grades. The salesman is a one-time B&W fan also. I have plenty of salicylic acid. I will just try the glycols and some other solvents and see what works. What affect do solvents have on the film??..Evan

 

[Gerald Koch]

Can you pre-dissolve your salicylic acid in some alcohol?

Pre-dissolving the salicylic acid in alcohol or a glycol may not help. This technique works with chemicals like phenidone that are difficultly soluble in water but eventually dissolve ie, they are at a concentration below their maximum solubility. Adding an alcohol solution of salicylic acid to try to get 4 g/l to into solution will only result in 2 g/l actually dissolving and the the other 2 grams precipitating out. The maximum solubility of salicylic acid is only about 2g/l. This would prevent making DS-10 in a 5X concentrate.

 

[Alan Johnson]

PanF+ gave very nice white clouds/blue sky tones in DS-12. I think it is well established that isopropyl alcohol is unlikely to have any adverse effect on the film.G.W.Crawley recommended its use in FX-1 at least since 1962,it is said to improve keeping properties of the developer.

 

[eclarke]

Pre-dissolving the salicylic acid in alcohol or a glycol may not help. This technique works with chemicals like phenidone that are difficultly soluble in water but eventually dissolve ie, they are at a concentration below their maximum solubility. Adding an alcohol solution of salicylic acid to try to get 4 g/l to into solution will only result in 2 g/l actually dissolving and the the other 2 grams precipitating out. The maximum solubility of salicylic acid is only about 2g/l. This would prevent making DS-10 in a 5X concentrate.

That makes sense, I will just grin,bear it, and wait for it to dissolve. The results are great with Tmax 100..Thanks..Evan

 

[gainer]

Pre-dissolving the salicylic acid in alcohol or a glycol may not help. This technique works with chemicals like phenidone that are difficultly soluble in water but eventually dissolve ie, they are at a concentration below their maximum solubility. Adding an alcohol solution of salicylic acid to try to get 4 g/l to into solution will only result in 2 g/l actually dissolving and the the other 2 grams precipitating out. The maximum solubility of salicylic acid is only about 2g/l. This would prevent making DS-10 in a 5X concentrate.

True enough, but if the object was to make it quicker to get 2 g/l or what ever the recipe called for, keeping the salicylic acid in some kind of separate solution would do that. The 3 % solution of Scalpicin has 30 grams per liter in propylrne glycol, some other alcohol and water, so one would only use a little of that to make a liter of working solution with 2 g/l or less.

 

[eclarke]

I haven't had any sheets I wanted to risk but I think I will expose a few test sheets and try the salicylic acid dissolved in some alcohol prior to mixing the DS-10. I can compare the test sheets to DS-2 at this time also. I dissolved Phenidone in alcohol for the Mytol formula, maybe it will work here...Thanks all, I will post my observations (probably tonight, I have developed 20 sheets in the last couple days and must mix some DS-10 again)..Evan

 

[Gerald Koch]

Rather than a glycol solution it might be easier to keep a stock solution of TEA and salicylic acid on hand. This avoids adding an additional component to the mix. Salicylic acid should be easily soluble in such a basic solution.

 

[eclarke]

Rather than a glycol solution it might be easier to keep a stock solution of TEA and salicylic acid on hand. This avoids adding an additional component to the mix. Salicylic acid should be easily soluble in such a basic solution.

Thanks Gerald,
That sounds like a good alternative, I have plenty of TEA. What temperature do you think I should take the TEA to for best solubility??..Evan

 

[Gerald Koch]

To test that it works, I would mix up 100 ml of TEA and 10 g of salicylic acid to make a 10% solution. I would add the acid to the TEA. It may dissolve without having to heat the mixture since a salt is formed which is triethanolamine salicylate. If it doesn't dissolve then I would gently warm the mixture with stirring until it does. You would then use 10 ml of the mixture for each liter of DS-10 made. If you find the mixture too viscous to measure easily then add an equal volume of water and use 20 ml of the mix for each liter.

 

[Gerald Koch]

I was able to get salicylic acid USP through my local pharmacy on special order. I paid $13 for 100 grams.

You can also get it from www.techcheminc.com for $12 for 100 grams.

 

[Tom Hoskinson]

To test that it works, I would mix up 100 ml of TEA and 10 g of salicylic acid to make a 10% solution. I would add the acid to the TEA. It may dissolve without having to heat the mixture since a salt is formed which is triethanolamine salicylate. If it doesn't dissolve then I would gently warm the mixture with stirring until it does. You would then use 10 ml of the mixture for each liter of DS-10 made. If you find the mixture too viscous to measure easily then add an equal volume of water and use 20 ml of the mix for each liter.

You may need to add a few ml of water to the TEA/salicylic acid mixture to get everyting into solution and form the triethanolamine salicylate.

To reduce the viscosity of the TEA/salycilic acid mixture you can add some warm Proplene Glycol (about 100F). I successfully use this method with the DS recipes that require salycilic acid .