Abstract Conventional extraction of natural dyes requires more energy and time. This research investigated a rapid and low-cost extraction method for red yeast rice, utilizing a pressurized extraction process with a coffee maker machine. The application of the extract for dyeing cotton fabrics was also investigated. The effects of extraction time, particle size, and temperature on the color value (CVU/gds) were investigated. The particle size varied at 16, 18, and 20 mesh, the extraction temperature varied at 85, 90, and 95 °C, while the extraction time varied at 3, 6, and 9 s. The dyeing process variables studied were reapplication and dilution of the extract solution. Reapplication was varied at the 1st, 2nd, and 3rd dyeing, while dilutions were varied by 1, 2, and 3 times. The highest color value is 15.3105 CVU/gds, obtained at a 20 mesh particle size and 85 °C of extraction. At a significance level of α = 0.05, reapplication up to 3 times had no significant effect on color strength (K/S); the K/S of 0.1813 decreased to 0.1521. At the same time, the dilutions significantly decreased the K/S, resulting in a K/S of 0.0129. The wet and dry rubbing fastness test was rated from very good to excellent (4.5–5), whereas the washing fastness test was rated as poor (1–1.5). The subsequent study should investigate the extraction process using higher pressure and organic solvents, as well as determine suitable mordants and higher temperatures for fabric dyeing.
Margono et al. (Thu,) studied this question.