Sublimation Transfer Printing of Wool with Metallizable Dyes

The transfer printing of pretreated wool using sublimable dyes that form metal complexes on the fibre during printing is described. The most successful pretreatment involved padding a mixture of chromic chloride, an anionic surfactant, urea and lactic acid and then drying. Low molecular-weight monoazo dyes containing salicylic acid residues, or hydroxyl or amino groups on carbon atoms in two ortho positions relative to the azo group, were screen printed onto transfer papers. Optimum heating conditions for transferring dye from paper to fabric were 200 °C for 30 s. After reparation of the transfer paper, the fabric was steamed at 100 °C for 30 min. Prints with good fastness properties were obtained in a wide range of colours. The method offers promise for commercial transfer printing of pure wool fabric