Preparation of Alizarin Al(Ⅲ)Complex and Its Dyeing on Polyester Knitted Fabric
In order to shorten the dyeing process,alizarin and Al(Ⅲ)complex dyes were prepared and charac-terized by ultraviolet-visible and infrared spectroscopy.The dyeing effects of alizarin and Al(Ⅲ)complex dyes on polyester knitted fabrics were analyzed and compared with the same dyeing process.The results show that the opti-mal process parameters for the preparation of alizarin and Al(Ⅲ)complex dyes are as follows:n(alizarin):n(Al3+)=2:1,pH value 5.00,reaction temperature 40 ℃,and time 30 minutes.When the dyeing pH value is 3.00,the K/S value of yellow spectrum polyester fabric dyed with complex dyes increases by 81.69%.When the dyeing pH value is 9.00,the K/S value of red spectrum polyester fabric dyed with complex dyes increases by 11.72%.Dyeing polyester fabrics with alizarin and Al(Ⅲ)complex dyes has a dry rubbing fastness of more than grade 3,a wet rubbing fastness of more than grade 2~3,and a soaping and fading fastness grade of 4~5.