Abstract: Dyeing properties of polyester/polyamide fiber (referred to as modified polyester) and it’s cotton blended fabric were researched based on determination of boiling water shrinkage rate of modified polyester fabric, the best pretreatment conditions of modified polyester/cotton(65/35), and K/S and color fastness of modified polyester fabrics dyed under normal pressure and modified polyester/cotton dyed with disperse/reactive dyes one-bath one-step method. The experimental results have shown that warp and weft shrinkage rates of modified polyester and it’s cotton blended fabric were lower than 5% after heat setting. Optimization conditions of pretreatment process of modified polyester/cotton fabric was H2O2 of 4 g/L, scouring agent of 3g/L and NaOH of 4g/L. Modified polyester fabric could be dyed under normal pressure. Levelness performance of disperse/reactive dyes one-bath one-step dyeing was satisfactory. Fastnesses to ironing, sunlight and dry rubbing of dyed samples were reached 4 grade and above.

Key words: polyester/polyamide, blended fabric, dyeing under normal pressure, one-bath one-step process, color fastness