Advertisement

Laser Cleaning of Undyed Silk: Indications of Chemical Change

  • K. von Lerber
  • M. Strlic
  • J. Kolar
  • J. Krüger
  • S. Pentzien
  • C. Kennedy
  • T. Wess
  • M. Sokhan
  • Wolfgang Kautek
Part of the Springer proceedings in physics book series (SPPHY, volume 116)

Three different undyed, unweighed silk fabrics (new clean, new soiled, and naturally aged) were cleaned with a computer-controlled Q-switched Nd:YAG laser at 532nm in 30 combinations of fluence and pulse numbers. They were studied for chemical change by viscometry, X-ray diffraction, and FIB-SIMS in combination with temperature calculations. While physical changes only occurred above the tested parameters, chemical changes could be detected as low as 0.2 J cm?2 with four pulses. Yellowing was observed at lower and bleaching at higher fluence/pulse number combinations. Melting was observed in naturally aged silk cleaned with 64 pulses at 4.2 J cm?2. The temperature reached at 0.1 J cm?2 is sufficient to evaporate carbon. Excess energy is transferred into the silk substrate causing thermal degradation. Different chemical processes leading to chain scission and to crosslinking seem to occur simultaneously, even at low fluence and pulse number. An increase in pulse numbers also leads to increasing damage.

Keywords

Chain Scissioning Pulse Number Laser Cleaning Carbon Dust Laser Clean 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • K. von Lerber
    • 1
  • M. Strlic
    • 2
  • J. Kolar
    • 3
  • J. Krüger
    • 4
  • S. Pentzien
    • 4
  • C. Kennedy
    • 5
  • T. Wess
    • 5
  • M. Sokhan
    • 6
  • Wolfgang Kautek
    • 7
  1. 1.Prevart GmbH – Textile ConservationWinterthurSwitzerland
  2. 2.Faculty of Chemistry and Chemical TechnologyUniversity of LjubljanaLjubljanaSlovenia
  3. 3.National Centre for Preservation of Library MaterialsNational University LibraryLjubljanaSlovenia
  4. 4.Division VIII.2 Surface TechnologiesFederal Institute for Materials Research and TestingBerlinGermany
  5. 5.Structural Biophysics Group, School of Optometry and Vision ScienceCardiff UniversityCardiffUK
  6. 6.Materials DepartmentImperial CollegeLondonGreat Britain
  7. 7.Department of Physical ChemistryUniversity of ViennaAustria

Personalised recommendations