The volume of water consumed by human beings has increased dramatically in recent years while water supply has remained constant; both demographic growth and the expansion of industrial activity require more water consumption. The textile industry is undoubtedly one of the most pressured industries that need water intensively. Efficient use of water tends to be a crucial subject for the dyeing industry. In this study, melamine resin microcapsules containing pure disperse dyes were prepared by in situ polymerization. The microcapsules were characterized on the basis of structure, morphologies, mean particle size, and size distribution. The dyeing behaviors of microencapsulated disperse dyes (MDDs) were evaluated on polyester fabrics in the absence of auxiliaries. Its effluent can be reused several times after being simply filtered and can be used as solvent for PET fabric scouring. The treated fabrics exhibited satisfactory levelness and fastness properties. MDDs can be used in dyeing PET, without using surfactants, and the effluents can be recycled and reused. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 113: 3774-3781, 2009