Volume 8, Number 3, Sept. 1986, pp.11-12

Technical Exchange

Application of Light Cured Composite Resins as Fill Material

The Antiquities Conservation Department of the J. Paul Getty Museum has begun to investigate the use of visible light cured resins in objects conservation.

The material, a mixture of Bis glyacetyl methacrylate and other resins, is a commonly used dental restorative material. As it is biocompatible, its physical properties also appear to be compatible with conservation uses.

Its major advantage over auto polymerizing resins is that it can be moved, shaped, textured, etc. indefinitely before curing is effected by application of the curing light.

Cure is initiated by blue spectrum visible light and in practice any intense light source containing blue light applied to the resin will achieve cure. This department has found that a fiber optic microscope light will cure a 1-2 mm depth of material in approximately one minute. Successive layers of resin can be built up using a bonding agent of triethylene glycol di-methacrylate between layers. The basic color of the material is opaque white and it can be easily shaped, sanded, finished and painted as desired. Thus far use at the J. Paul Getty Museum has been confined to small fills in ceramic objects and in this application it has proven qute successful. The Getty obtained its materal through Dr. Jan Orlowski of Scientific Pharmaceuticals, 1828 Evergreen Street, Duarte, Ca. 91010.

Health Insurance

Conservators in private practice or in part time positions in institutions face more and more costly health insurance expenses. The newly formed specialty group of AIC, Conservators in Private Practice, is looking into a possible group plan. Perhaps WAAC could work as a West Coast liaison to put together the needed list of people with the statistics the insurance company need: the person's age and number of dependents. Alternatively, if enough people are interested, WAAC could accomplish the same thing independently. If you are interested in either possibility, I would greatly appreciate hearing from you. Please drop me a note or call me with the above information.

Conservation Materials has Just Put Out its New Catalogue Featuring Some New Products

These include:

• Zin Shofu (Japanese Precipitated Wheat Starch) manufactured in Japan by the Nakamura Co. which has specialized in precipitated wheat starch for several generations. Precipitation removes the glutamine from the starch and the resulting cooking paste is exceptionally smooth.
• Tenax Glue, a transparent polyester based adhesive useful in gluing together very heavy pieces of pottery, especially where maximum strength is required at the joint. Tenax is noted for its excellent lightfastness and is sold as a two part kit: resin plus catalyst.
• Book Snakes, sewn tubes of dark blue polyester velvet, filled with glass beads. They are intended to hold things down without excessive weight.
• Horsehair strainer, a classical Japanese paste strainer; beautifully made by a family named Mizokawa who live near Kyoto. This family has been making them by hand for generations.

To find out about these and many other products call Doug, Dorothy or Sam at (702) 331-0582.