Non-yellowing casting resins

In response to Virginia Naude's question about non-yellowing casting
resins, I would say that you'll just have to live with a little
yellowing.  It's all a matter of degree, partly owing to the
thickness of the cast fill or reproduction.  Recent batches of Hxtal
have been quite satisfactory, but again in thick castings (over 0.5
cm) you may detect some yellowing within 5 years. You might want to
contact Sidney Williston, Mario's Conservation Services, in
Washington, D.C. (202-234-5795), who has done extensive testing on
Hxtal, and counteracts the yellowing with a minute (virtually
imperceptible) addition of blue.

Other epoxy resins will also give you good results, particularly
Epotek (Epoxy Resins Technology), and Fynebond (supplied by Norman
Tennent).  As you are bulking and tinting the resin, you should have
less noticeable yellowing over time.

Stephen Koob
Conservator
The Corning Museum of Glass
One Museum Way
Corning, NY 14830
 607-937-5371, ext 241
Fax: 607-937-3352

                                  ***
                  Conservation DistList Instance 12:81
                  Distributed: Tuesday, April 20, 1999
                       Message Id: cdl-12-81-011
                                  ***