JAIC 1984, Volume 23, Number 2, Article 3 (pp. 101 to 113)
JAIC online
Journal of the American Institute for Conservation
JAIC 1984, Volume 23, Number 2, Article 3 (pp. 101 to 113)


Merrily A. Smith, Norvell M. M. Jones, Susan L. Page, & Marian Peck Dirda


SOLUBILITY TESTING with solvents presents difficult problems. Their low surface tension allows solvents to wick rapidly into the paper. A too liberal application of solvent will bleed very soluble inks, colors, paper dyes, or sizes. On the other hand, because solvents tend to evaporate quickly, a sufficient quantity of liquid must be used to get meaningful results. Finally, because solvents are toxic, testing must be done in the fume hood, where the draft compounds the evaporation problem and often no microscope is available.

The first step in testing should be carried out on the paper itself in a non-image area. This step is critical because many papers, especially contemporary ones, contain sizes, dyes, or fillers that will move in some solvents. The following series of steps constitutes one possible procedure for testing paper.

  1. Select solvent
  2. Apply small drop
  3. Blot
  4. Air dry
  5. Check front and back
  6. Apply larger drop to same area
  7. Air dry
  8. Check front and back
  9. Repeat, repeat, repeat

Repetition of the process at least three times in the same area is imperative to approximate the effects of the relatively large amount of solvent actually used in tape removal. Particular care in testing is required if the adhesive is to be removed with a poultice because of the lengthy exposure to solvent this technique involves. Some papers form yellow rings with all of the solvents that are likely to remove the tape. In such cases select the solvent that causes the least movement, then use it cautiously.

The second step is to test inks and colors. As with paper, repeated testing in the same spot is necessary because media that appear stable initially may move unexpectedly and quickly with prolonged exposure to the solvent. Just because an ink is stable for five minutes in an acetone bath does not mean that it will remain stable for six minutes. Media testing might be approached as follows:

  1. Select solvent
  2. Apply small drop to pigment or ink
  3. Blot, either directly or with the edge of the blotter to pick up the liquid
  4. Check blotter
  5. Check media front and back for feathering or sinking
  6. Repeat
  7. Repeat, air dry (This step is important, because inks that appear stable, even with immersion, may move as the solvent evaporates.)
  8. Repeat until absolutely convinced

Copyright 1984 American Institute of Historic and Artistic Works