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Svinotype: A Photographic Process Using Easily Available Reagents

So... I've done a first experiment with borax added to the solution. Most of the copper was reduced to metallic copper, but a very very faint image was formed. The faint image disappeared after drying. I also discovered that if the first wash is made in a weak solution of hydrochloric acid, the contrast is much increased and white backgrounds are obtained, resulting in red over white pictures. The problem is that pictures produced this way don't last the drying step, turning into verdigris. I tried converting the metallic copper to CuO (a light-fast black pigment) w/ some Hydrogen Peroxide, with no success.
 
for what it is worth, i have done some free style quick tests to see if I can get anything with Copper Sulfate and ascorbic acid.
I coated the paper with this and then covered it with plastic wrap to keep it moist. then on top a negative inkjet foil. this showed very little reaction. However there after I removed it and tried some intense UV exposure with a UV Flashlight. Which did show for a short moment while drying a reaction, it is about 100 times (guess) slower than cyanotype and only works for a short moment while drying. After that it does not change and is no longer sensitive for UV light. In that case no washing is required.

I would have to do the experiment again to get a better way of working with it. The 3 points is the imprint of the 3 LEDs in that light.
 
That's very interesting...
 
Chromium VI said:
So... I've done a first experiment with borax added to the solution. Most of the copper was reduced to metallic copper, but a very very faint image was formed.
Click to expand...
So everything turned black/brown? Or yellow? The "whites" are supposed to be strongly yellow before fixing (unless you pre-treat the paper with chloride/bromide instead of alkali).

You can get stable images by first fixing with alkaline (Na-)Thiosulfate solution, then toning with either silver bearing fixer, ferricyanide (takes quite long) or polysulfides.
 
@Jan de Jong the system is pH sensitive, if you just mix copper sulfate and AA it does not do much. For it to be able to plate out metallic copper or quickly react to form copper (I) halides you need to raise the pH just slightly by adding e.g. NaHCO3 or Na-Ascorbate to the mix. Raising the pH too much is also bad, it will make the solution spit out Cu2O(?), sometimes with a significant delay depending on temperature and concentration. This freshly precipitated compound is not immediately light sensitive, IIRC it needs to be exposed to a lowered pH first. Maybe it's initially CuOH or has some mix of OH- and O2-.

This solution is not light sensitive itself, you need to make it precipitate CuCl, CuBr or Cu2O on the paper, the light converts these compounds into the seeds for the physical development. With UV light and high contrast negatives I'd try bromide first.
 
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Hello Anton, yes, you are right. I just used tap water which has PH 8, I tried various other things later on that also adding KBr, and NaHCO3. the KBr was making it worse. What did work, but expected was adding Thio sulfate, but then we are back to the "cuprotype" more or less based on thio (fix) I was also thinking about borax but did not try that. I have to start over and do bit more controlled experiments.
 
@Jan de Jong You need to raise the pH a bit, as Anton mentioned, and NaHCO₃ works just fine. But if you mix NaHCO₃ directly into the solution of CuSO₄ and AA, it may be difficult to actually get the copper precipitate on the paper (you can make a copper mirror this way though). What helps is to leave the mixture of CuSO₄ and AA as is (just that nice green liquid), but soak the paper in NaHCO₃ solution and let it dry. This way copper tends to precipitate on paper, and also you can keep relatively stable and non-sensitive CuSO₄ + AA solution around for quite a while during the experiments.
 
thank you that is a good suggestion ie soak the paper and then add the emulsion. I will try that next.
 
Yes, after exposure, there is a brown image over a dark yellow background, which is fine but I wold rather loose some density and have a white background. I found that if the first wash is to be made in a weak HCl solution the whites are turned white and the shadows in cuprous red, rather beautiful actually, but those images readily turn into verdigris while drying only the deepest shadows keep their density intact.
 
My measuring cylinders will never be the same. I will try it out. I tried mixing some borax on the sensitizing solution but it precipitated quite a lot of copper. After exposure, the paper was very fogged with copper, but after washing there was a fain image there. I will also do some experiments by saturating the paper in borax solution as well as other readily available alkali. I do think that the beauty of this process relies on its simplicity and ease to find reagents, so we should keep it that way.
 
Some images using my version of the process. The only paper that I managed to get working was normal photocopy paper, and it warps with the water. I tried backing it with some plotting, newspaper, and more copy paper, and all methods prevented the process from working.
The image looks very red due to the natural light filtered by the giant Amberlith window on the lab.
 

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@Chromium VI these look quite detailed! Did they survive the drying or did they fade in the end? One thing I found helpful to prevent paper from going all wavy is to make sure that the liquid covers the whole sheet, leaving no dry areas, and overflows a bit. It's even worth it to press the negative to the paper with a sheet of glass slightly larger than the paper. This way the paper still wraps, but it wraps evenly, instead of producing these ridges, and when it dries, no light stripes appear where the layer of liquid was thinner.
 

I haven't seen them yet, I left them in the lab on Saturday, and haven't been there since. After washing, I soaked the prints in gum arabic so it creates a protective coat over the copper, and then I dried them with very hot and dry air (around 300ºC) which prevented the copper from oxidizing. These prints are A5 size, and they where printed sanduiched w/ a A4 size sheet of 5mm glass and a Platex backing. As the paper I'm using is normal printer paper, here in Portugal is mostly made by Navigator and is Kraft process paper, the fibers are all in the same direction and I tried soaking the paper a lot (the lab is copper everywhere) and adding a lot of pressure and the waviness is very difficult to deal with.
 
Found one! Completly gone. Found another, turned black over blue. Found a third, that didn't show anything at the moment, but now the image is there... I don't get it.
 
Chromium VI said:
Found one! Completly gone. Found another, turned black over blue. Found a third, that didn't show anything at the moment, but now the image is there...
Click to expand...

Were all these done with your Borax idea? Did a similar thing happen with Bicarbonate?
 
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