Excimer laser cleaning of mud stained paper and parchment

The main advantage of excimer lasers when processing materials, its the emission of a radiation with wavelength in the ultraviolet region. This characteristics allows an extremely accurate and very well defined shape of material removal as well as total absence of heat affected zone and alterations in the material structure. In excimer laser paper and parchment cleaning, the mud is removed by breaking the physical-chemical bonding between this last one and the material to be cleaned not affecting neither its structure nor the chromatic pigment existing in some samples. (Author) 3 refs