Surface color changes of oak (Quercus alba L.) treated with dopamine and iron ion compounds by acceleration of temperature–humidity condition

Abstract

To change the surface color of oak (Quercus alba L.) to dark and grey, the water-soluble iron ion compounded dopamine solution was applied and accelerated in temperature–humidity condition. The colorimetric parameters before and after treatment were measured and X-ray photoelectron spectra were carried out for a further understanding. The results showed that iron ions and the compounds can significantly cause color changes to the oak, while the compounds treated groups seemed more uniform. With increasing concentration of the colorants, the color change was more obvious. During acceleration in temperature–humidity condition, the oxidation occurred, which further caused color change to oak. However, different oxidation reactions might occur between iron ions and compounds treated groups. The compounds system was more sensitive to temperature–humidity condition. Thus, the color difference was the highest. In a word, this treatment was effective considering the coloring effect and safety process.