Photodegradation of three hardwood species by sunlight and xenon light sources

Abstract

The behavior of three hardwood species was investigated in response to natural and artificial light irradiation. The effects of irradiation were evaluated by their color measurement in the CIELab system and Fourier-transform infrared (FTIR) spectra. Both natural light irradiation and artificial light irradiation induced changes in color, such as yellowing and darkening, in the wood species. Comparative in-time evolution of changes in color during artificial light irradiation and natural light irradiation under indoor conditions resulted in an estimated acceleration index that ranged from 60x to 90x. The FTIR spectra highlighted specific changes in surface chemistry during irradiation. Ultraviolet light from natural or artificial sources primarily resulted in lignin degradation.