JAIC 1987, Volume 26, Number 1, Article 4 (pp. 45 to 58)
JAIC online
Journal of the American Institute for Conservation
JAIC 1987, Volume 26, Number 1, Article 4 (pp. 45 to 58)

THE OZONE FADING OF TRADITIONAL NATURAL ORGANIC COLORANTS ON PAPER

Paul M. Whitmore, Glen R. Cass, & James R. Druzik


ABSTRACT—This report details the results of an ozone exposure experiment performed on a large number of traditional natural organic colorants applied to watercolor paper with no binder. These colorants were exposed in an environmental chamber to an atmosphere containing 0.397 .007 parts per million (ppm) ozone at 72F and 50% RH in the absence of light for 12 weeks. This ozone concentration is typical of that found in the Los Angeles atmosphere during a heavy smog episode. The total ozone dose delivered to the samples is equivalent to about four years of exposure to outdoor air in Los Angeles or to about eight years inside a typical air-conditioned building in Los Angeles.The ozone sensitivity of these colorant systems was evaluated by monitoring the color changes which occurred during the exposure. Almost all colorant systems tested showed some degree of fading after ozone exposure, and a few of these (curcumin, dragon's blood, indigo, and madder lake) should be considered very ozone-fugitive.

Article Sections:

1. INTRODUCTION
2. EXPERIMENTAL
3. RESULTS
4. DISCUSSION
5. CONCLUSION
a: References
Entire Article

Copyright 1987 American Institute for Conservation of Historic and Artistic Works