U of S | Mailing List Archive | alt-photo-process-l | Re: polymer plate drying time

Re: polymer plate drying time


When I put the plate into the drying cabinet on high temp, the cabinet's cold to start with, so I guess the temp over a 10-15min period will never get to the maximum that Toyoba mention. I'll have to check it out.


On Mar 16, 2007, at 7:11 AM, SusanV wrote:

Keith and Jon,

After all this talk about drying time and such, this morning I exposed
and developed a test strip then skipped the hairdryer stage and went
straight to the oven set at 100 degrees.  I figured a few minutes at
100 to dry it, then bump the temp up for a few more minutes as per
Keith's Toyobo instructions.  Well........... after 10 minutes I
checked it, and it had bubbled and kind of melted in all the darkest
areas!  There are also larger (pencil diameter), flat bubbles in the
mid to light tones that appear to be the polymer detaching from the
plate base.  The plate didn't get that warm... when I took it out of
the oven it was just a little warm in my hand, not hot at all.  SO....
it appears that the moisture in the polymer needs to escape more
slowly than the 100 degree oven allowed.  Also I would speculate that
since those deep bubbles occurred, separating the polymer from the
base, there was moisture down at that level that became trapped when
the top layer dried more quickly.
So as usual, haste makes waste :o)   we need to be sure they have
sufficient drying time before any heat curing, and I'd suggest testing
the heat thing before trying it on something important.  I'm going to
go re-do this now and I'll report back.