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- Cleaning (1)
- Collagen (1)
- Degradation (1)
- Iron gall ink (1)
- Laser (1)
- Lipids (1)
- Multivariate data analysis (1)
- SIMS (1)
- Silk (1)
- Small-angle X-ray scattering (1)
The applicability of excimer laser at 308 nm and Nd:YAG laser at 532 nm with fluences below 0.86 J/cm2 for cleaning of cellulose and paper materials was evaluated. The extent of degradation of purified cotton cellulose and Fabriano paper after laser treatment as well as after a period of accelerated humid oven ageing was determined by following the changes in the degree of polymerization. While irradiation of paper with the excimer laser at 308 nm results in depolymerization of cellulose accompanied by a decrease in ISO brightness, no detrimental effects of Nd:YAG laser treatments were observed.
Parchment has been in use for thousands of years
and has been used as the writing or drawing support for
many important historic works. A variety of analytical
techniques is currently used for routine assessment of the
degree of denaturation of historic parchment; however,
because parchment has a heterogeneous nature, analytical
methods with high spatial resolution are desirable. In this
work, the use of small-angle X-ray scattering (SAXS) and
synchrotron-IR (SR-IR) was examined in conjunction with
multivariate data analysis to study degradation of an
extended set of historic parchment samples, and particularly
to investigate the effect of lipids and the presence of iron
gall ink on the degradation processes. In the data analysis,
shrinkage temperature, lipid content, sample age, presence
of ink and accelerated degradation were included. The
analysis of loading factors in partial least-squares regression
and principal component analyses based on SAXS, SR-IR
and other analytical and descriptive data reveals the effect
of lipid removal on diffraction patterns, and lipids are found
to cause the degradation process in parchment to accelerate.
The effect of iron gall ink is also evident, although the
mechanism of ageing is different to that of natural ageing in
the absence of ink. In addition, a historic parchment score
from ca. 1750 is examined, demonstrating the significant
effect of iron gall ink, and lipids and inorganic soiling on its
increased degradation.