Union dyeing of polyester / cotton fabrics with indigo dyes

For solving the problem that indigo dyeing polyester / cotton blended or mixed fabrics are difficult to reach good union dyeing effect,the influences of sodium dithionite dosage,sodium hydroxide and benzyl alcohol,dyeing temperature and time on K / S value of polyester / cotton fabrics were studied,and the color fastness of the dyed fabrics was tested.The results showed that the polyester / cotton fabrics are difficult to get union dyeing effect by one step and one bath method with indigo dyes as the dyeing process for single polyester and cotton fabrics are different.Polyester and cotton fabrics reached good union dyeing effect,satisfied dyeing depth and dyeing fastness when the fabrics firstly were dyed with indigo 2%(o.w.f.),at 100 ℃ with benzyl alcohol 20mL / L or at 120 ℃ without benzyl alcohol for60 min,and then dyed with indigo 6% ~ 8%(o.w.f.),at 30 ℃ for 60 min.