The use of D-optimal design in optimization of wool dyeing with
Juglansregia bark
In this study, wool fibers were dyed using the Juglansregiabark as a new source of natural dye. Alum was used as mordant. Response surface methodology and D-optimal design were employed to study and optimize the dyeing procedure with the aim of obtaining the maximum color value after dyeing with aqueous extract of Juglansregiabark. The results showed that the color value of the dyed fibers was increased by increasing the dyeing time and temperature and decreased by increasing the dyebath pH value. There was an optimum value of around 6 % owf for mordant concentration. The optimal condition for obtaining the highest color value was as follows: dyebath pH: 6, alum concentration: 6.24 % owf, dyeing temperature: 90 ºC, and dyeing time: 90 min.