Low Temperature Dyeing Of Wool Using Ethylenediamine Pretreatment And Weak Acid Dyes With Rare Earth As Auxiliary Agent

The purpose of the present thesis is to determine the appropriate dye formula and process by pretreating the wool through pretreatment agents such as ethylene diamine firstly, and then dyeing the pretreated wool by weak acid dyes with rare earth as the auxiliary agent in low temperature dyeing bath.Based on the previous work of low temperature dyeing of pretreated wool and low temperature dyeing of wool using the wake acid dyes with the addition of rare earth, three pretreatment agents for wool are screened as the main component of pretreatment to determine the parameters of pretreatment by single factor experiments respectively. On the basis of the previous studies on low temperature dyeing using the weak acid dyes with rare earth added, the low temperature dyeing ingredients and process using the weak acid dyes with rare earth added are determined through the single factor experiments. By orthogonal test, the appropriate ingredients and process for the low temperature dyeing using the weak acid dyes with rare earth added urea, ethylene diamine and ammonia/salt are determined for three pretreatment respectively. By comparing and analyzing the results of low temperature dyeing for three pretreatments, this paper finally finds out the most appropriate formula and process.It follows from the experiments that:(1)The amount of ethylenediamine for wool pretreatment is 0.4mol/l, the pretreatment holding temperature is 65℃, and pretreatment holding time is 30min.(2)The formula of adding rare earth in weak acid dyes after ethylenediamine pretreatment is as follows Weak acid brilliant blue RAW (owf): 2% Rare earth mixture of LaCl3 and CeCl3 (owf): 0.15% Leveler UL (owf): 0.5% Penetrant SP-2 (owf): 0.3%The corresponding dyeing process is: pH of 4.5, holding time for 45min, holding temperature at 75℃and liquor ratio of 1:50.Compared with the low temperature dyeing of ethylenediamine pretreatment, the dye uptake of the low temperature dyeing of adding rare earth in weak acid dyes after ethylene diamine pretreatment increased1.92%, the wet rubbing fastness increased 0.5 level, and the holding time was shortened 15minutes. Compared with the low temperature dyeing of adding rare earth in weak acid dyes, the holding temperature decreased 5℃, the dye uptake increased 0.4%. Compared with conventional dyeing of weak acid dyes, the holding temperature decreased 23℃, the dye uptake increased 0.15%, and the fiber strength increased 1.63CN.The results indicate that the wool dyeing quality using the weak acid dyes with rare earth as auxiliary agent after ethylene diemine pretreatment is better than those using the pretreatment or the weak dyes with rare earth added, and the fiber damage and dyeing holding temperature are both lower than conventional dyeing.