Abstract

Due to the large amount of toxic effluents generated by the textile industry using most of synthetic dyes, natural dyes are increasingly gaining prominence, in keeping with the global trend toward prioritizing the use of cleaner technologies. However, the application of natural dyes is still restricted, mainly due to their instability in solution and poor fixation onto textile substrates. Thus, research is required to improve the performance of these dyes in order to obtain products with the characteristics desired by the industry. In this study, the potential of natural annatto dye in the dyeing of polyester (PES) fiber was analyzed and the color and stability parameters in solution were evaluated through two experiments. Initially, the stability of the natural annatto dye in solution was determined under different conditions of temperature, pH, and dye concentration and the application of this dye in conventional PES fiber dyeing was investigated. Subsequently, the influence of the use of a carrier in the dyeing of PES fiber was evaluated. The results indicated that the variables with the greatest effect on the degradation of the dye are temperature and pH. The natural annatto dye showed good interaction with the PES fiber in the conventional dyeing process, presenting good results of color yield and levels of fastness. In the dyeing processes conducted with and without a carrier, the dyeing performed in the latter provided better results, with the advantage of allowing the application of lower temperatures.

中文翻译：

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安那托染料在溶液中的稳定性的比色分析及其在涤纶纤维染色中的应用

摘要

由于纺织工业使用大多数合成染料产生了大量有毒废液，因此与全球优先使用清洁技术的趋势保持一致，天然染料越来越受到重视。但是，天然染料的应用仍然受到限制，这主要是由于它们在溶液中的不稳定性和在纺织品基材上的固定性差。因此，需要进行研究以改善这些染料的性能，以获得具有工业所需特性的产品。在这项研究中，分析了天然胭脂红染料在涤纶（PES）纤维染色中的潜力，并通过两个实验评估了溶液中的颜色和稳定性参数。最初，在不同温度，pH，研究了染料的浓度及其在常规PES纤维染色中的应用。随后，评估了在PES纤维染色中使用载体的影响。结果表明，对染料降解影响最大的变量是温度和pH。在常规的染色过程中，天然的安纳托染料与PES纤维表现出良好的相互作用，从而表现出良好的颜色产量和牢度水平。在有载体和无载体的情况下进行的染色过程中，在后者中进行的染色提供了更好的结果，其优点是可以施加较低的温度。评估了在PES纤维染色中使用载体的影响。结果表明，对染料降解影响最大的变量是温度和pH。在常规的染色过程中，天然的安纳托染料与PES纤维表现出良好的相互作用，从而表现出良好的颜色产量和牢度水平。在有载体和无载体的情况下进行的染色过程中，在后者中进行的染色提供了更好的结果，其优点是可以施加较低的温度。评估了在PES纤维染色中使用载体的影响。结果表明，对染料降解影响最大的变量是温度和pH。在常规的染色过程中，天然的安纳托染料与PES纤维表现出良好的相互作用，从而表现出良好的颜色产量和牢度水平。在有载体和无载体的情况下进行的染色过程中，在后者中进行的染色提供了更好的结果，其优点是可以施加较低的温度。