The most likely cause of your problem is an inadequate gelatin sizing of
the Fabriano paper. I have also expereinced this problem with sized
water-color papers.
There could of course be other problems, i.e., the paper was soaked too
long before combining it with the tissue, or perhaps you allowed the tissue
itself to absorb too much water. Both conditions are made worse by high
temperatures and humidity.
You can somtimes salvage a print with these bubbles by pricking the bubble
but usually the drying ring will be evident. Instead of pricking the bubble
you might try and pour a little acetone on it. This will sometiems save a
carbon relief that has partially lost contact with the final support. The
solution, however, is to apply a better layer of gelatin size.
Sandy King
>Help!
>
>All of a sudden I am getting a number of blisters on my carbon prints.
>This is air trapped between the wet emulsion and the transfer sheet.
>The tissue is very well squeegied to the transfer sheet.
>If I prick these bubbles the emulsion drys flat but little rings are
>obvious since the emulsion has been stretched. The transfer paper
>is Fabriano Artistico 90% (100% cotton) brush coated with ca. 3%
>gelatin solution w/ 3% glyoxil hardener.
>
>Thanking all in advance for their words of wisdom,
>
>Cheers,
>
>Al
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