Abstract: Polyester inking agent has a good inking effect on polyester/spandex color defective fabrics. However, polyester inking agents will cause spandex strength loss. The paper evaluates the strength loss of spandex by the elongation rate of the treated fabric and discusses the influence of the spandex content and size in the polyester/spandex grey fabric on the strength loss of the spandex. The research indicates that the polyester/spandex grey fabric with 30% spandex content and a relatively high aspect ratio is used as the evaluation fabric, which is beneficial to the evaluation of spandex strength loss (reducing measurement errors). In the experiment, the polyester/spandex inking agent TF-216G has no damage to the spandex strength in the polyester/spandex grey fabric and has a good inking effect on the defective fabric. And its dye migration performance is better than that of compatible products on the market.

Key words: polyester inking agent; spandex strength loss; evaluation method; TF-216G