REGALREZ IN FURNITURE CONSERVATION
Regalrez 1094 is used in paintings conservation for saturation and as a top varnish. It can also be used for saturation on furniture. Unfortunately, Regalrez 1094 gets tacky by the warmth of one's hand, thus making it less useful as a top finish. The higher molecular weight grade of Regalrez 1126 does not get tacky when handled and forms an alternative in furniture conservation both for saturation and as a top finish for furniture. Regalrez 1126 can produce a very smooth top varnish with a 20-40% (w/w) solution. Moreover, it is very effective in saturating heavily degraded varnishes; usually only a 10% solution or less is needed. Thus it allows conservators to retain varnishes that might otherwise be removed. Shellac or Paraloid B-72 can be applied on top and taken off without affecting the finish. Because most old varnishes on furniture are polar, applying or reversing a film of Regalrez is likely to cause less damage to the old finish underneath than would be the case with more polar finishes like shellac or Paraloid B-72. Therefore, Regalrez can also be used as a barrier coat between old varnishes and more polar finishes.
Furthermore, because Regalrez is compatible with waxes, Regalrez 1126 is also a good alternative for dammar in wax-resin finishes. Due to the fact that Regalrez easily dissolves when a coat of wax is applied on top, it might not be suitable as a top varnish on furniture in private collections.
Saturating a degraded finish, with whatever material, is by definition irreversible because there is no way one could get the material all out again. Saturation should be undertaken only when the finish would otherwise be removed and with the most stable materials. In this perspective, Regalrez is a better alternative than the more traditional materials and methods used in furniture conservation, such as natural resins, furniture reviver, or melting in a new coat of wax.
The author wishes to thank the following people for their useful comments concerning the article: Jaap Boonstra, Marie Laibinis, Gregory Landrey, René de la Rie, and René Smit and Bob Wherry of Hercules. I also wish to thank Maurice Steemers, Bart Gogherman, Marieke Hengeveld, and Jimya Hoevers for supplying scrap parts of furniture and for their help with the tests.