Monochrome pigment tissue on polyester support

Stefan Stecher (Stefan.Stecher@htw-kempten.de)
Wed, 24 Jan 1996 12:04:39 +0100 (MET)

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Hi Luis and all !
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I had a private internet conversation with Luis about the subject stated=20
above but I thought it might be of any interest for other folks on the list=
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as well.
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I coated a few sheets of (pre-sensitized) monochrome pigment tissues using=
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polyester (Mylar-D 0.075 mm) as a support instead of paper.
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It has a lot of advantages compared to tissue coated on ordinary paper base=
:
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- easy to coat (perfect surface)
- easy to handle (back of the tissue is absolutely clean cause the=20
dichromate does not penetrate the support and you need no gloves when=20
touching
- Perfect sharpness (good contact with the neg in the printing frame)
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The problem is the processing after exposing the tissue as usual (NOT=20
through the back!)
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When soaking the tissue for too long after exposure the tissue does not=20
stick to the final (baryta paper), when soaking time is too short it is=20
difficult to seperate the tissue/final sandwich when developing and I got=
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uneven densities in the mid-tone areas and damages in the image because the=
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plastic support prevents the hot water from the gelatin.
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I thougth it would be a good idea to use a relative short soaking time
to provide good vacuum between tissue and final but to start developement
at a very high temperature e.g. 60=B0C to help gelatin to melt.
Does anyone agree or could anyone give me exact informations how to process
this material (processing times / temperatures)
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Does anyone use plastic supports for monochrome work or would you call me
a fool ? :-)) =20
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Best regards
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Stefan
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