From: Clay (wcharmon@wt.net)
Date: 12/13/02-06:02:53 PM Z
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.
Two cents worth.
Clay
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