Investigation of non-aqueous remedial treatments for iron-tannate dyed textiles

Iron-tannate dyes accelerate the degradation of the substrates they colour, severely decreasing the material’s lifetime. This paper presents preliminary results focusing on the development of non-aqueous remedial conservation treatment(s) to inhibit degradation. A range of antioxidants and deacidifiers in organic solvent applied to model iron-tannate dyed cotton and silk fabrics and the effects of the treatments on accelerated ageing of the cotton have been evaluated using spectrophotometry and handling tests. The results show that there is little correlation between colour and strength of the samples after ageing. Strength-retention is considered of greater importance than colour-retention. The protective agents showing most potential are Tinuvin 292, Tinuvin 144, alpha-tocopherol, phytic acid, etidronic acid and magnesium ethoxide. Completion of the cotton and silk analyses will identify the most promising treatments for further investigation.