From: Judy Seigel (jseigel@panix.com)
Date: 01/08/02-10:32:15 PM Z
On Tue, 8 Jan 2002, clay wrote:
> When you say the working solution doesn't keep, I assume you mean the
> diluted 20 cc / liter with 1/2 tsp bicarbonate mix don't you? Not the 40%
> concentrated version?
Right, the other is I believe 40% and seems to keep at least a couple of
years in the original bottle. (I judge by does it still smell strong.) I
find BTW, that 15 cc per litre is fine... I leave paper in the hardening
bath 5 minutes, with the occasional interleaving or slosh. After that, you
can if you want give it a very *brief* rinse in plain water... (But don't
rinse if you give a shorter bath, like 2 minutes... yes, I actually tested
those variables.)
I don't do the bicarb any more by the way... It's one of those things I
THINK is more theoretical and/or psychological than actual. Which is to
say I've never NOTICED any difference in the way the size lasts with or
without and I worried it might darken the size. I have no evidence that it
does, you understand, but I don't miss it either.
I'm told that methyl alcohol is a preservative for both formaldehyde and
glyoxal, and that the working solution of glyoxal would keep better with
iabout 20% added, but if it did it only was 20% better, not enough. I
judge the glyoxal by odor also -- same day it still has that
characteristic odor. About 2% of what the formaldehyde has you understand,
but noticeable up close. When that's gone I just don't take a chance.
Isn't worth the 50 cents or whatever 15 cc costs to risk my labor & paper.
However, if you have some paper with bad size or hardener, unless it's got
warts or something, you can put on another size & reharden over that.
good luck,
Judy
This archive was generated by hypermail 2b30 : 02/15/02-11:47:41 AM Z CST