香云纱工艺中晒莨工序的染色机制

采用高效液相色谱、红外光谱等测试手段，考察香云纱工艺中晒莨工序前后薯莨单宁组分与结构的变化、纤维材料结构的变化情况，结合植物多酚化学理论，探讨晒莨工序的染色作用机理。认为：一、在晒莨工序中，曝晒使薯莨单宁氧化形成醌式结构而显棕色，因此随着浸染、曝晒次数的增多，晒坯表面的颜色不断加深，最终变为棕色或棕红色。二、疏水键-氢键多点结合可能是薯莨单宁与丝、棉、麻等纤维结合的共同方式；化学结构的不同使得各种纤维与薯莨单宁结合的数量、强度差异很大，因而影响染色牢度。蚕丝结构中含有疏水性氨基酸以及众多的氢键结合点，可形成大量的疏水键-氢键结合，因此可获得良好的加工效果。三、丝绸加工效果好的另外两个可能的原因是薯莨单宁与蚕丝蛋白形成共价键结合，以及蚕丝丰富的原纤结构，使得薯莨单宁与蚕丝的结合点显著多于其他纤维。

Dyeing mechanism of sunning process in production of gambiered Guangdong silk

To investigate the dyeing mechanism of the sunning process, the chemical constructive changes of dioscorea cirrhosa tannin and fibers before and after processing were analyzed by high performance liquid chromatography ( HPLC ) and infrared spectroscopy ( IR ) . According to the test results and in combination with plant polyphenols chemical theory, it shows that firstly, during the sunning process, dioscorea cirrhosa tannin was oxidized and converted to quinoid structure by solarization. With the deepening of the process, the surface color of the fabric became darker, eventually became brown or brownish red;secondly, the multipoint combination of hydrophobic bond and hydrogen bond may be the common mode in which Dioscorea cirrhosa tannin combined with silk, cotton and hemp fiber. The number and strength of combination varied greatly with the difference of fibers′chemical structure, thus affecting dyeing fastness. Hydrophobic amino acids and many combining sites for hydrogen bonding were contained in silk structure, so that a large number of hydrophobic bonding and hydrogen bonding could be formed, and a better processing effect could be achieved; and thirdly, the other two possible factors contributing to silk′s good processing effect were, respectively, the covalent bonds between tannin and silk, and the richness of silk′s fibrillar structure, which significantly increased the bonding points between silk and tannin, compared with the other fibers.