Cleaning of the Emulsion

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Conservation Treatments

(NORRIS, DEBBIE HESS, 1998)

Surface cleaning shouldn’t be a standard treatment. Every treatment should be tested first on a small spot under magnification.

Contents

[edit] Possible reasons for cleaning treatments

  • Improvement of legibility of information and detail
  • Improvement of stability due to removal of deteriorating adhesions
  • Protection of the surrounding materials

Extreme caution with:

  • Molded or otherwise degraded material
  • Lifted emulsion
  • Varnished (partial or complete) negatives

[edit] Typical cleaning treatments

  • Mechanical treatments should be carried out very carefully: soft brush together with a vacuum device, sulfur-free vinyl-eraser as a powder or similar is also possible
  • Solvent cleaning (e.g. distilled water, ethanol, acetone, trichloroethane: very toxic, can damage protection varnishes) applied by cotton swabs, cotton balls or cotton pads
  • Chemical sponges
  • Saliva
  • Commercial film cleaning agents: can contain chlorinated hydrocarbons or ethyl acetate
  • Bathes in aqueous solutions
  • Ultrasonic bath (trichloroethane, 5 minutes at 25°C)

(GILLET et al., 1986)

[edit] Collodion Emulsions

  • Extremely sensitive against mechanical damage (can be polished by eraser)
  • Soluble in acetone and ethanol
  • Treatment could contain cleaning with a soft brush, saponified bath, water, air drying

(MOOR, I., 1976/7)

[edit] Gelatin Emulsions

  • Solvent cleaning with a mixture of ethanol and water: ethanol can dehydrate the gelatin, water can swell, soften and solve it especially if the emulsion is already degraded
  • 0.1% solution of ammonium hydroxide in water: can swell the protein binder, ammonia can complex silver salts which could lead to decreased density
  • Silver mirror shouldn’t be removed as a side effect of surface cleaning, only if removal by itself is an aim of conservation

[edit] References

    • GILLET et al., 1986. Gillet, Martine; Garnier, Chantal; Flieder, Francoise. Glass Plate Negatives. Preservation and Restoration. Restaurator, 7(2), 49-80
  • MOOR, I., 1976/7. The Ambrotype. Research into its Restoration and Conservation. The Paper Conservator, 1, 22-25 (part 1), 2, 36-43 (part 2)
  • NORRIS, DEBBIE HESS, 1998. Surface Cleaning of Damaged Photographic Materials; Current Practice and Concerns. In S. Clark ed. Care of Photographic Moving Image & Sound Collections, 20th-24th July 1998, York, England. Institute of Paper Conservation. 96-101
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