Glass colored prints

Stephen Fowles <sculpture [at] nmgmcc1__demon__co__uk> writes

>Does anyone have experience of working on glass prints which are
>badly deteriorated?

I've studied the technique of glass colored prints (or glass-prints
or back-paintings on glass as they also are called) closely and just
made a successful conservation of a piece, a portrait from late 1600
or early 1700.

About the technique. It seems that any kind of varnish was used to
glue the print to the glass. The descriptions of the technique which
I've collected from the sources (from the period where the prints
were popular, late 1600 until 1800) differ a bit. Venetian Turpentine
though seems to be mostly recommended for this part of the process.
But mastic-varnish, sandarac-varnish, nutoil, linseed-oil and others
are also mentioned. After having glued the print to the glass, most
of the paper was rubbed off and the remaining part varnished to make
it transparent. The second varnish was often a mastic-varnish, but
again, different varnishes as the above mentioned could be used.
Finally the print was painted, most often with either oil colours or
varnish colours.

If you need further information, don't hesitate to let me know.

Anne Povlsen
The School of Conservation,
Copenhagen, Denmark.

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                  Conservation DistList Instance 11:88
                    Distributed: Friday, May 1, 1998
                       Message Id: cdl-11-88-001
                                  ***