Pretreatment of silk fabric surface with amino compounds for ink jet printing

This research studied pretreatments of silk fabric with amino compounds for ink jet printing. The pre-treating solutions were serine, glycine, aspartic acid, sericin, chitosan, and a commercial pre-treating chemical called Sanfix 555. Both untreated and treated fabrics were printed with in-house formulated pigmented inks and later steamed to fix the ink on the fabric surface. The pretreatments containing the amino compounds improved hydrophilicity of the silk fabric with the exception of chitosan. The color gamut from sericin, chitosan, and Sanfix 555 pretreatments was wider than that from the amino acid pretreatments. The chroma of the cyan color was most improved. The fabric, after pretreatment with sericin, showed a significant improvement in dry crock fastness while wet crock fastness was improved by serine and glycine. The chitosan slightly improved both dry and wet crock fastness. Wash fastness of all pretreated and printed fabrics including untreated and the printed fabrics was excellent because the pigmented ink was formulated with pigment and binder. Bending stiffness of the silk fabrics after chitosan pretreatment was significantly higher than those with other pretreatments. The ink penetration in sericin and chitosan padded layers was shallower than those for amino acids, enhancing ink deposition on the fabric surface. The amino compound pretreatments held and fixed additional ink on the fabric surfaces resulting in a wider color gamut of the inks.