Re: oil-print-glyoxal??

Judy Seigel wrote:
>
> On Mon, 27 Dec 2004, henk thijs wrote:
>
> > The big difference with the bromoil versus oil-printing is the fact that in
> > oil-printing there is no developping, no fixing, no washing, no tanning, no
> > bleaching , no fixing and no washing ....:-)
> > In short, the oil-process is just a gelatine sized paper with a
> > kalium-dichromate. Just the neg on top, UV-light, washing in plain water and
> > voila: the matrix.
>
> Which answers my question about dichromate & probably means that mold
> wouldn't be a problem -- there would be enough tanning even in the
> highlights to harden the gelatin... as seen in my reverse step ladder in
> gum, as explained by M. Ware.

I'm sorry, you're going to have to explain to me how this works in the
present context of oil printing. I assume by "tanning" you mean
crosslinking. If the gelatin becomes crosslinked enough even in the
highlights to harden it, as you state here, then that same gelatin
wouldn't be able to take in water and swell and repel the ink; in other
words, the highlights would take ink as well as the shadows and the
process wouldn't work the way it's supposed to work. Either the gelatin
is hardened or it's not. For your explanation to work, the gelatin has
to be hardened, but for the oil printing process to work, the gelatin
has to be not hardened. It can't be both ways.
Katharine
Received on Mon Dec 27 22:17:58 2004