Dyeing of Wooden Parts with Organic Dyes by Boiling Together Method

Abstract

Wood specimens were dyed by boiling them in the presence of walnut shells and dye to penetrate the dyestuff into the sample. Specimens prepared from Scots pine, oak, and beech woods were boiled separately in walnut shell, water, and NaOH environment, and the penetration of the dyestuff into the samples was ensured. Sodium hydroxide solution was preferred because it facilitates the dissolution of the hemicelluloses in the wood and the dyestuffs in the walnut shell. Alum was added in other samples to reveal the mordant effect on the adhesion of dyestuffs to wood. Thermogravimetric (TG) analysis revealed that wood degradation primarily occurs due to evaporation of free water at 50 to 120 °C, followed by lignin and cellulose breakdown across a wide temperature range of 160 to 600 °C. Treatment with NaOH and NaOH+alum notably reduced the peak temperatures in differential-thermogravimetric analysis by indicating an effect on lignin. This was supported by Fourier transform infrared analysis, particularly in the disappearance of carboxyl groups at 1710 cm^-¹ and significant decreases in peak intensities at 1027, 1247, 1315, and 1501 cm^-¹. Based on the findings, it was concluded that the dyed parts obtained can be used in the wooden toy industry.