The following quote from Dana Sullivan I think explains the importance of humidity to a paper's absorption better than I can. He is actually referring to pre-soaking paper in water, when high humidity is difficult to obtain. But the end result is basically the same:
. . . ( pre-soaking the papers works to) swell the surface fibers of the paper, helping them draw the VDB solution into them. You don't want the solution drying on the surface of the paper, or in between the fibers, rather you want each of the individual cotton fibers to act like a little capillary and hold the solution inside it.
david
On 2-Jun-08, at 11:22 PM, Judy Seigel wrote:
On Mon, 2 Jun 2008, david drake wrote:
I have had this problem with my Vandykes using Platine, whereas the Stonehenge paper has always worked well under the same circumstances. I have always thought that it was due to Platine needing more humidity to print. I'm fairly sure that a higher humidity allows the paper to absorb more sensitizer.
David,
would you explain to a lay person why higher humidity would lead to more absorption? I would have thought that dryer conditions would mean more liquid would be soaked up...????
There's probably some simple principle I'm missing... but it does confuse...
thanks,
J.
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