9 CONCLUSIONS

A method was devised, working in a saturated atmosphere, that will produce similar minimal changes in appearance as when working with a low-volatility solvent such as DEB. The method was developed and evaluated based on the principle that greater penetration and spreading resulted from solutions of low viscosity when a low-resin concentration was maintained by inhibiting solvent evaporation. The method also differs from placing an object in a saturated atmosphere after consolidation because a broad range of solvent volatilities can be accommodated. By working in a saturated atmosphere, even a highly volatile solvent such as acetone may be used successfully.

Simple visual evidence (figs. 9–10) is sufficient to support the conclusion that darkening resulting from consolidation can be minimized by inhibiting solvent evaporation. Further work in this area should involve quantitative studies of appearance change (color measurements), which could provide specific information relating the extent of darkening to concentrations of consolidants, solvent volatilities, solution viscosities, distributions within a paint layer, and adhesive strengths.

ACKNOWLEDGEMENTS

The authors would like to thank Robert Feller, Ruth Johnston-Feller, Sue Walston, and Zeno Wicks for comments and suggestions. Portions of this paper were presented at the Objects Specialty Group Session of the AIC Annual Meeting in Richmond, Virginia, 1990.