Study On Grafting Modification And Dyeing With Cationic Fluorescent Dyes Of Silk Fabric

Silk fabric has good luster, excellent drapability and a soft touch, wearing light and comfortable, at the same time, it also has good hygroscopicity, moisture permeability air permeability, and has been known as the king of fiber. Silk is grade textiles. Both international and domestic market demand for silk products style, color fastness is higher and higher. The silk dyed by cationic dyes has high dyeing percentage, bright color, and many high brilliance color and fluorescent effect pattern, that other dyes have not, but it also has poor color fastness.This paper mainly studies is that the silk fabric that was grated with anionic grafting agent has bright color and good fastness dyed by cationic dye. Details are as follows:The first part is the synthesis of anionic grafting agent. The cyanuric chloride,sodium sulfanilate, and para-ester were the reagents. The best synthesis process of anionic graft agent is that: cyanuric chloride : sodium sulfanilate: para-ester =1:1:1.The first step condense reaction condition of cyanuric chloride and sodium sulfanilate as follow: ice water bath, 2h, pH value is 5. The two step condense reaction condition of intermediate and para-ester as follow: temperature is 45℃, pH value is 6, time is 3.5 h. The anionic graft agents with best reaction condition has good grafting effect.The second part is grafted and dyeing of silk fiber. The adsorption type of cationic fluorescent dyes were judged by measuring the adsorption isotherm, dyeing heating-rate curve, dyeing saturation value. With a single variable method optimization process, the determination of dyeing percentage, K/S value, soaping fastness, dry and wet fastness as judgment standard.It was found that the method of grafting and dyeing silk is one bath and one step. The dosages of grafting agent,dyes, odium carbonate and IW were 4%o.w.f, 1%, 2g/L, 15g/L.The initial temperature was 40℃, and then rose to 80℃,holding time was 25 min, the liquor ratio was 1:20. The results showed that sorption isotherm is still a Langmuir type. The dry and wet rubbing fastness are in grade 4, the cotton and acrylic color fastness are in grade 4, and its silk stain fastness is poor which is in grade 2 and is need improved by fixation. But it is not improved after fixation. It can be founded the strength of warp-wise is 4.76%,of broad-wise is 29.5% after testing the dyeing silk.Through the comparison for three experiments: weak acid red fluorescent dye, cationic fluorescent dyes dye silk and cationic fluorescent dyes dye the modified silk fiber, can discover the good property of the modified silk fiber dyed with cationic fluorescent dyes. At the same time, the modified silk fiber can be dyeing with different cationic fluorescent dyes.