Svinotype: A Photographic Process Using Easily Available Reagents

Jan de Jong said:

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.
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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.

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Chromium VI said:

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.

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AntonKL said:

@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. 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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