A cotton fabric durable press (DP) finished with citric acid (CA), as a non-formaldehyde cross-linking agent, was subjected to testing for soil removal properties, which are of great importance considering end-use by consumers. The CA-treated and untreated cotton fabrics were artificially soiled with iron oxide as a representative particulate soil and then laundered in various detergent solutions. The soil removal was evaluated by reflectance measurements on the fabrics before and after laundering. The fabric treated with CA showed increased or decreased detergency compared with the untreated control depending on detergent used, pH and water hardness of wash bath. Improved soil removal was observed in the fabric treated with CA when laundered under mild alkaline conditions and in the presence of calcium ions. FTIR/ATR spectra on the fabrics after repeated laundering suggested existence of unesterified free carboxyl groups or carboxylates in the CA-treated fabric and their contribution to enhanced soil removal by ionization during laundering.

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