姜黄染色织物的pH值敏感变色性能

为开发pH值敏感变色织物，研究了pH值对姜黄染色织物颜色变化的影响，利用高效液相色谱法对姜黄提取物主要成分进行分析，测试了不同pH 值条件下姜黄提取液的吸收光谱、姜黄染色织物的上染率、K/S值和染色牢度，利用颜色特征值对姜黄染色织物在不同pH值下的变色情况进行表征。结果表明：植物染料姜黄的主要成分为姜黄素，姜黄素分子在碱性条件下会电离成阴离子，引起颜色变化；随溶液ｐＨ 值的增加，姜黄提取液的吸收峰会产生红移，且吸收强度增加，提取液在酸性条件时呈黄色，当提取液pH 值大于8 时，溶液呈红棕色；姜黄对丝织物的染色性能好于棉织物。在pH值由中性向碱性转变时，姜黄染色织物会产生显著的变色，染色织物色相值变小，颜色由黄色域向红色域转变。

Discoloration property for pH-sensitivity of fabric dyed by turmeric

In order to develop pH-sensitive color changing fabrics,the influence of pH on the color change of fabrics dyed by turmeric were studied.The main chemical compositions of dye extracted from turmeric were analyzed by high performance liquid chromatography (HPLC).The absorption spectra of turmeric solution at different pH values were tested.The dye uptake and the color fastness of fabric dyed by turmeric were measured.The color changing properties at different pH values of samples dyed by turmeric were evaluation by means of the values of CIELAB.The results show that the main chemical component of vegetable dye extracted from turmeric is curcumin.The curcumin molecules are ionized into anions under alkaline conditions,and the color of curcumin changes.With the pH value of the solutions increasing,the absorption peaks of the turmeric extraction solution have red shift and the absorption intensity increases.The color of the turmeric extraction solution is yellow under acid condition.When the pH value of the extracted liquid is greater than 8,the solution color is reddish brown.The dyeing property of curcumin for silk fabric is better than for cotton fabric.The color of fabric dyed by curcumin has a significant change when the pH value is changed from neutrality to alkality.The hue value becomes lower,and the fabric color changes from yellow to red.