The Quantification of a Fluorescent Tracer Dye in Treated Southern Yellow Pine Cross-sections

摘要

Direct visualization of the penetration of organic actives in treated wood presents a challenge. Proxy compounds such as dyes have been used to demonstrate active penetration but the quantitative correlation of actives and proxies has not been well-studied. In this study, the distribution of DCOIT (4,5-dichloro-2-octyl-4-isothiazolin-3-one) within fully-treated and partially-treated Southern Pine samples was evaluated using Scanning Electron Microscopy with Energy-dispersive X-ray Spectroscopy (SEM-EDS). The results were compared to the penetration of the AWPA standardized fluorescent dye marker system. Qualitative results indicated that the fluorescent dye is inherently conservative. Imaging and image analysis systems were developed to quantify the marker dye fluorescence from the wood cross-section areas analyzed by SEM-EDS. Comparison of the fluorescence from the marker dye with the DCOIT data confirms the correlation between DCOIT and dye penetration observed qualitatively.