I wonder if the bleach contained in E6 developing kits would work? Or maybe just plain old ferric chloride?
I think it might have been the old dichromate bleach.
What is the formula for dichromate bleach?
AAAAAAAKKKKKK. You had to ask that.
OTOMH, it would be 50 g/l Potassium Dichromate and 50 - 100 ml / L of 37% Sulfuric Acid (battery acid). Just a guess, but more dilute is ok it just takes more time.
And regarding,That is certainly my understanding as well. I've transferred magenta dye to a fixed-out (non-hardening) FB paper and the density is very good, but diffusion is terrible! The mechanism of imbibition though, relies on this pH gradient and not a mordant.Quote:
I thought a Thorium salt was needed just to enhance sharpness not to actually hold the dye in the receiving gelatin?"
Speaking of which... you can buy thorium nitrate on eBay for fairly low prices. Not that I'm even considering such an endeavor..
I have personally used uranyl nitrate mordant with and without aluminum, with the combined effect being a bit sharper. Depends on the receiver paper. But I'd have to defer to Jim's experience on that point. Regarding the use of pigment directly in the relief film and opacity, the hypothetical solution is
much finer pigments which in effect behave as if they were more transparent in relation to saturation. This can be done, but I've already got way to many irons in the fire to do the testing myself per ideal process colors. The carbon printing crowd seems completely unaware of some of the
significant advances in pigment technology which might be applicable. But nothing at this point has
been marketed for process work per se, so there are chroma issues (but nowhere near as bad as back which things like alizarin crimson and poison green were used). One more test which will have to
wait till I retire.
You guys are talking about a kind of Duxochrome thing, eh?
Hexavalent (Ian) has been toying with this idea I think, on the spurring of CMB.
But if hardening is such an issue with polymers, I just fear that none of these schemes will apply well. It makes little sense to set out learning guitar with one hand tied behind your back, or trying to build a car that doesn't use wheels.
Of course finding a way to do it with PVA would be a really great contribution, but gelatin & in turn leather have been utlized for centuries because of its unique property to tan. I'm not sure we should expect a polymer to have any of these same characteristics.
From the nature of the bleach involved it looks like Duxochrome involved dyes, not pigments. (???)