Freshly cut hardwood lumber such as white oak, red oak, beech, or redwood are rich in mineral stain (mostly iron and calcium), which provides a strong discoloration of the wood surface significantly influencing the aesthetic of the wood surface and strongly affecting the cost of this lumber. The influence of mineral stain on soft wood discoloration (Southern Yellow Pine, Douglas fir, etc.) is less significant mostly due to the lower mineral content. Special treatments of wood surface with the so-called brightener could significantly improve the aspect of the wood, maintaining the clean aspect for a wood surface. Various types of wood species and commercially available phosphate-based precursors (inorganic-phosphoric acids or salts and organic-phosphonic acids or phosphonates) were considered in this study. The wood chemical modifications leading to a bright wood surface is explored and explained. The effect of various brighteners and the presence of corrosion inhibitors on the overall corrosion for an antisapstian treatment are being investigated. Models or standard possible reactions are being studied for better understanding the observed phosphate-mineral interaction/structure. The chemicals formed during the treatment using various brightener and most probably responsible for the brightening effect were investigated using Fourier transform infrared (FTIR) and scanning electron microscopy equipped with energy dispersive X-ray analyzer (SEM-EDX). These findings are important and used for developing better wood brighteners utilized in antisapstain chemical treatment.

Download document (307 kb)
free for the members of IRG. Available if purchased.

Purchase this document