From: kerik (kerik@kerik.com)
Date: 12/13/02-06:26:51 PM Z
Clay,
Your observavtions match mine exactly. I've sworn off glyoxal for good and am now hardening with formaldehyde. I'm gel coating first,
then hardening as a separate step. I'm of the opinion that the hazards of formaldehyde the way I'm using it are way overblown.
Especially given the fact that little is known about the health effects of glyoxal because it's a pretty obscure chemical that hasn't been
studied in detail the way formaldehyde has.
I'm using a 1.25% solution (of the 'full-strength' 37% formaldehyde - so it's really a 0.5% soltion) for a hardener. I wear a respirator and
keep the solution in a covered tray while I'm working with it. I set it in my sink right next to my exhaust fan. After hardening, I hang up
the paper to dry, then leave the room with the door closed and the fan on at least overnight.
I'm much more likely to be killed driving around looking for photographs than to have any health effects from this approach.
I'm hoping it'll preserve me as I age...
Kerik
>Just thought I would drop yet another bit of data to the glyoxal
>yellowing discussion. When I brought this up before, most list members
>indicated that prompt wet processing through the gum steps would keep
>the sizing from yellowing. That has indeed been my experience. I have
>had no subsequent yellowing as long as I do the rest of the gooey work
>promptly.
>
>Well, last weekend, I sized five prints that I had every intention of
>throwing the gum on in the next couple of days. Yeah, I know, five
>prints. I always super-size it. As could be predicted, real life
>intervened and I didn't get to them until today (Friday). The five
>prints had been in a stack in my darkroom, and the sizing on the one on
>top had already begun yellowing! Strangely, the ones beneath it were
>fine. So what I learned was: 1) size paper with glyoxal hardener pretty
>close to its actual anticipated use and 2) there must be some effect
>that unrestricted air circulation above the face of print accelerates
>the yellowing process.
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