Study on the dyeing properties of Chinese fir with Cinnamomum camphor pigment by premordant dyeing

Abstract

ABSTRACT Wood staining can improve the quality of Chinese fir. In this study, Cinnamomum camphora natural plant pigment was used as a substitute for synthetic dyes to stain Chinese fir, and the staining performance was enhanced through pre-mordanting with alum. The dyeing effects of direct dyeing and mordant dyeing were compared, and the factors and levels influencing color difference, wash fastness, and light fastness were investigated through an orthogonal experimental design. The results showed that mordanting time had the greatest influence on color difference and lightfastness, while mordanting temperature had the greatest influence on washfastness. After pre-mordanting, the washfastness of Chinese fir improved to a level of 2–3, while the improvement in lightfastness was not significant. Pre-mordanting increased the dye uptake rate by 6.67%. Scanning electron microscopy revealed that NaOH pretreatment opened the wood pores and increased the flow channels for dye liquor. Infrared analysis indicated that O-H in wood fibers formed complexes with Al3+ in the mordant, resulting in a decrease in the characteristic peak intensity of O-H. X-ray diffraction analysis showed that the attractive effect of Al3+ vacant orbitals on O-H partially influenced the ordered arrangement structure in the crystalline region.