Sulfamic Acid for Paper Acidification

[sklimek]

Hi Stan, great news.

About the colder tone; could be the acid is breaking some of the original size in the paper (or fibres to some extent) and letting the paper retain more moisture than usual, leading to colder tones. Do you get more whisper / printout (and speed) than usual? I noticed that sulfamic acid treated papers become a little more absorbent than non-treated ones...

Regards,
Loris.

Hi Loris,

I'm not sure if it is breaking some of the original size/fibers that is yielding these cooler tones. I just finished a project w/ sulfamic using Rives BFK and this paper as well yielded cooler tones. Rives is a printmaking paper w/ little size in comparison to Arches WC which has quite a bit of size, so I suspect not? What is 'whisper'. Since I can't compare arches WC and rives for speed/printout because I didn't have anything to compare it using my old ways. I could say that in the past I have printed on BFK w/ oxalic acid treatment but could not achieve the Dmax I am getting w/ sulfamic.

 

[Loris Medici]

Hi again,

If you're washing the papers after dealkalization w/ sulfamic acid, the cooler tones should be caused by some physical effect of the treatment, not because some chemical effects - since you remove the sulfamic acid from the paper by washing it. That was the key of my reasoning. If the treatment makes the paper retain more moisture, you'll get cooler tones, better dmax, more printout and faster speed.

Best regards,
Loris.

P.S. Whisper / whisper image is the incomplete printout (in the darktones) with dop pt/pd, it's a term borrowed from Christopher James' alt-process book. Don't know if anyone else was using this term before - apparently not.

 

[sklimek]

OK, great! I'm going to be testing on the new Fab Artistico Traditional which is an off white paper, 90lb in a few days to see if I what kind of results it yields, I'll post.

 

[Herzeleid]

Hi Stan,

Thank you for sharing your experience with various papers, your feedback is quite valuable. I will look into Arches paper, I think I can find it locally.
I had the chance to treat a few Arches HP papers with sulfamic acid, just to show the procedure to a friend.
My friend used modern cyanotype with those papers, and they worked as expected However I did not had the chance to test that paper entirely.


Best Regards
Serdar

 

[sklimek]

Well no luck with Fabriano Artistico Traditional 200gsm w/ 10% sulfamic. I keep hoping to use this paper again because i love the slight warm off white it comes in. Cannot get a good black, upon close inspection it is grainy. I'm going to go with the Arches 185gsm HP/WC white for this next project. It has worked out very well.

Stan

 

[Herzeleid]

Well no luck with Fabriano Artistico Traditional 200gsm w/ 10% sulfamic. I keep hoping to use this paper again because i love the slight warm off white it comes in. Cannot get a good black, upon close inspection it is grainy. I'm going to go with the Arches 185gsm HP/WC white for this next project. It has worked out very well.

Stan

Hello Stan,

I have tested FATW HP 200gsm (the reason I started a search for alternative acid) and later 300gsm, both papers gave poor dmax. FATW HP with or without acid treatment gives mediocre dmax even with traditional cyanotype, and vandyke brown. After SA procedure that did not change. In terms of argyrotype on FATW 200gsm, the blacks were worse than a single coat VDB on untreated canson montval.
I got better results with ordinary papers such as canson montval and schoellershammer duramatt compared to FATW HP papers. Although I liked its off-white color and the subtle texture on the reverse side of the paper, I must say it is a disappointment for siderotypes. I have tested traditional and modern cyanotype, vdb, argyrotype and salt prints too ( it is not a siderotype but I have tested it). Even salt prints was not satisfactory in terms of dmax. Considering that you have tested a DOP procedure, I believe we can assume that paper is not good for alt. processes except for gum and similar pigment processes.

On the other hand FAEW SP 300gsm papers are simply magnificent. I would like to hear your opinion on that paper, if you would have time to test it.

Regards
Serdar

 

[sklimek]

Hello Stan,

I have tested FATW HP 200gsm (the reason I started a search for alternative acid) and later 300gsm, both papers gave poor dmax. FATW HP with or without acid treatment gives mediocre dmax even with traditional cyanotype, and vandyke brown. After SA procedure that did not change. In terms of argyrotype on FATW 200gsm, the blacks were worse than a single coat VDB on untreated canson montval.
I got better results with ordinary papers such as canson montval and schoellershammer duramatt compared to FATW HP papers. Although I liked its off-white color and the subtle texture on the reverse side of the paper, I must say it is a disappointment for siderotypes. I have tested traditional and modern cyanotype, vdb, argyrotype and salt prints too ( it is not a siderotype but I have tested it). Even salt prints was not satisfactory in terms of dmax. Considering that you have tested a DOP procedure, I believe we can assume that paper is not good for alt. processes except for gum and similar pigment processes.

On the other hand FAEW SP 300gsm papers are simply magnificent. I would like to hear your opinion on that paper, if you would have time to test it.

Regards
Serdar

Hey Serdar, I agree with everything you said, time to let go of FATW. I'll try some of those papers you mentioned. BTW in my testing with BFK (good results), Arches WC/HP (good results) and FATW (bad results) I too have found the back of the paper more favorable...

Stan

 

[sklimek]

I will try out Fab Artistico Extra white 300gsm - thanx...

 

[Herzeleid]

I like to try BFK rives but those papers are not available locally, I would have to order them from off-shore. But I will try arches again, I liked the velvety surface of the hot press variety.

I think FAEW HP's surface texture would be identical to traditional white, but I haven't tried it. I would especially recommend soft press variety. It has a visible texture and yet the tooth of the paper is almost flat like hot pressed papers. I find it hard to explain There is minimal height difference between the peaks and the dents of its surface. Its textures effect on the print is quite subtle I am guessing you might like the surface.

Regards
Serdar

 

[Loris Medici]

Ditto, I print 8x10" pop pd on FEAW/SP and the texture isn't disturbing even at this small print size. I reckon it's a matter of taste, but I'm not much in fond of too textured papers and FAEW/SP OK to me at >= 8x10" print size. The dmax and tonality is great. See one example here.

Regards,
Loris.

 

[sklimek]

FAEW HP and FATW HP are identical in surface texture. Rivers BFK is a great paper, no doubt, but it is a printmaking paper compared to a watercolor paper which has 3 times of the sizing (so that the watercolor artist can keep moving the pigment around before it sets). In comparison of BFK to a HP WC paper there is more detail on the WC only when compared with a loupe. However when Rives BFK is married to the right subject matter it is bliss...

With either BFK, Arches and the old but great FATW/EW/HP I always printed on the back.

I'll definitely test FAEW/SP 300gsm and report back...

Stan

 

[mcilroy]

Just to report: I used sulfamic acid at 1% to acidify some sheets of Lanaquarelle 300g/m² satin, and it worked perfectly. Dmax is significantly improved.

I was wondering if i could also use sulfamic acid for washing cyanotypes? Normally i use citirc acid at 5%. Would i have to expect any negative effects when i switch from citric acid to sulfamic acid?

 

[Herzeleid]

Just to report: I used sulfamic acid at 1% to acidify some sheets of Lanaquarelle 300g/m² satin, and it worked perfectly. Dmax is significantly improved.

I was wondering if i could also use sulfamic acid for washing cyanotypes? Normally i use citirc acid at 5%. Would i have to expect any negative effects when i switch from citric acid to sulfamic acid?

Matthias,

It is interesting to hear another %1 SA success, your choice of paper tells a lot. Lanaquarelle papers' ph is close to neutral afaik, there are various threads on Lanaquarelle on DPUG. It seems %1 sulfamic acid works with papers containing lesser the alkaline content. I haven't tried %1 SA yet, but with the papers I am working it seems impossible to me. At %10 concentration acid-base reaction takes 15mins with some papers (e.g. FAEW SP).

If you are washing the paper thoroughly after sulfamic acid, the paper is free of acid and alkaline substances. So I would not think of any adverse effect.

Citric acid treatment creates calcium citrate inside the paper and it is not water soluble. Not that it would have an adverse effect like oxalate crystals, but I like the idea of completely cleared paper. But as I recall many people do not wash the papers after %5 citric acid treatment. If that is your practice too, acidic paper might be problematic with certain sensitizers, for example I would expect troubles with argyrotypes.

I am using %0,5 to 1 sulfamic acid for initial wash of modern cyanotypes. I wash the print for 30secs to 1min in SA, longer washing causes chemical fogging. I would not recommend SA for the initial wash of traditional cyanotypes due to its strong acidity. It might reduce the contrast too much and even fog the prints too fast. But it can be used for the latter clearing baths. But the papers should be washed well to remove the acid.

Regards
Serdar

 

[mcilroy]

Thanks, Serdar! I use the traditional cyanotype formula, so i will stick with a mild citric acid bath for the initial wash. I don't see fogging or a loss in contrast with concentrations up to 5%.

 

[mcilroy]

In the meantime, I tried a few other papers in a 1% solution, and it worked fine with all of them. But I found that the key to make it work, is to give the paper a good pre soak in plain water.

Some papers didn't show any reaction even after 20 minutes when I just dropped them directly in the SA bath. But after a pre soak of 20-30 minutes (no agitation, just dropped them in a tray with water), the reaction starts almost immediately and is done after about 5 minutes.
The SA bath was still clearly acidic after this, so i guess even a 0.5% solution might work. But I will stick with 1%.

 

[Andrew O'Neill]

Just to report: I used sulfamic acid at 1% to acidify some sheets of Lanaquarelle 300g/m² satin, and it worked perfectly. Dmax is significantly improved.

I reported that as well earlier in this thread but on Rising Stonehenge.

 

[Herzeleid]

Can you elaborate your procedure (steps and times), paper's you have used and the process you have tried them with?

Regards
Serdar

 

[mcilroy]

Besides Lanaquarelle, I treid Arches Aquarelle 300g/m², various Hahnemühle Watercolor Papers (Britannia, Cornwall, William Turner), Bristol Paper (don't remeber the brand at the moment) and some no-name art papers i happen to have.

1.) Pre soak in plain tap water for 20-30 minutes - depending on paper - until i felt that the paper was soaked.
2.) 1% SA bath until bubbling/fizzing stopped (about 5 minutes), but I gave it a minute extra to be on the safe side.
3.) Wash

I tried Cyanotype and Van Dyke Brown with similar results. Of course the effect of the SA treatment is more pronounced with some papers, but I guess thats not a sign of incomplete acidification, but just shows that different papers have different amounts of buffer in them.

 

[Herzeleid]

Besides Lanaquarelle, I treid Arches Aquarelle 300g/m², various Hahnemühle Watercolor Papers (Britannia, Cornwall, William Turner), Bristol Paper (don't remeber the brand at the moment) and some no-name art papers i happen to have.

1.) Pre soak in plain tap water for 20-30 minutes - depending on paper - until i felt that the paper was soaked.
2.) 1% SA bath until bubbling/fizzing stopped (about 5 minutes), but I gave it a minute extra to be on the safe side.
3.) Wash

I tried Cyanotype and Van Dyke Brown with similar results. Of course the effect of the SA treatment is more pronounced with some papers, but I guess thats not a sign of incomplete acidification, but just shows that different papers have different amounts of buffer in them.

Traditional cyanotype and VDB are not that alkaline sensitive, they are not benchmarks for determining paper's chemical purity. They would have worked without SA treatment. You might get improved results using SA. You can use %5 citric acid as well, you can wash the papers in acid until the fizzing stops, then hang them to dry (without washing) and use it for VDB. But as I said it works because those processes are not alkaline sensitive.

Modern cyanotype, argyrotype, DOP pt/pd, ziatypes won't work with papers containing any chemical impurities. I especially test papers with modern cyanotype and argyrotype, if both works then everything else would work.

 

[mcilroy]

True, but i don't think that it wouldn't have worked with other processes. The SA treatment first neutralizes and then acidifies the paper, no matter if the solution is at 1%, 10% or any other concentration.

Of course the capacity of the solution and the time it takes differ with concentration, and one has to make sure that the concentration is high enough to neutralize the buffer for a given amount of paper. But as I said, even at 1% the solution was still acidic after i treated the papers.

I used 1 liter of the 1% solution to treat about 1800 cm² (about 290 square inches) of paper.

 

[Herzeleid]

If you washed the paper thoroughly afterwards, the paper should not be acidic. Acidic papers would cause fogging especially sulfamic acid and modern cyanotype combination (any other AFO using process would act similar imo). Sulfamic acid is a very strong acid, but at room temperature it acts slow, at 70C it acts as fast as HCl. But the slow action is the advantage, it does not damage the paper's fibers much like the other acids.

But you are right of course %1 would neutralize less alkaline content. If 1lt 1M SA solution (ca %10) can neutralize 14 papers, %1 might neutralize 1,4 papers (sheet size 56x76cm). But halfway through the life of the acid (0,7 sheets) the neutralization time would increase dramatically (almost doubles with some papers). %1 acid would work but for fewer papers, and I am concerned about the neutralization time and therefore consistency of the results.

It would not effect traditional cyanotype and VDB adversely, but it is a problem for alkaline sensitive siderotypes.

If I tested %1 SA for one sheet of paper (e.g. FAEW 300gsm), I would probably say it works but I am not sure overall it is a good practice, because compared to the second sheet in the same %1 the results would be inconsistent. I de-alkalise papers by batch, and %1 would not last for whole 2 sheets.

 

[Andrew O'Neill]

That's a very good point, Herzeleid.

 

[Andrew O'Neill]

For the hell of it, I acidified a sheet of Stonehenge in a bath of vinegar, diluted 1:1. Worked very well. Vinegar is heaps cheaper than sulfamic acid. Not yet sure of it's capacity, though, so more testing to do.

 

[Herzeleid]

Hello Andrew,

Acetic acid would neutralize the buffer as well but I haven't tested it on purpose. My excuse is mainly the smell of it and in higher concentrations it would irritate respiratory system causing asthma like symptoms. Also it is weaker acidity and probably low capacity compared to SA. Vineagar is usually %3-5 acetic acid which is weaker than using concentrated acetic acid, and it still smells irritationg (especially if you are neutralizing a batch of papers). However, I must say calcium acetate is highly water soluble byproduct, which makes acetic acid/vinegar a better option than oxalic acid but cost wise vinegar's capacity won't match sulfamic acid.

The part from my old post on the subject on vinegar.

Sulfamic acid vs Acetic Acid/Vinegar (Rather, why I haven't tested it)
-Vinegar is unreliable due to additives IMO, and the acidity changes from brand to brand
-I did not want to try concentrated acetic acid due to its strong irritating odor.
-Acetic acid is also a weak acid (around ph4 as I recal)
-Byproduct of reaction is highly water soluble calcium acetate.

That was it actually, why I haven't even tested acetic acid/vinegar. Strong odor, weak acidity and probable cost due to its weakness.
I know some people use vinegar or acetic acid, and if it works for them that is great , but cost wise, I find SA to be a better choice.

Regards
Serdar

 

[Herzeleid]

Hello again,

I made a quick search and it seems, 1M acetic acid (similar to vinegar) may neutralize similar amount of CaCO3.
However I have no idea about the reaction times, and I have no idea how it would behave after the solutions starts to get loaded with calcium acetate.

If you have tested it, how long did it take to neutralize the paper?

But still the problem of irritating smell remains, and the shelf life. For me the smell is a major set back, it can trigger my allergies.

Regards
Serdar