Abstract: With the advancement and expansion of the printing and dyeing market, China has emerged as the world's leading textile producer and trading nation. In the textile industry, color serves as a crucial parameter for evaluating textile quality. During factory production, the concentration of dyes in the dyeing process primarily influences the color of textiles. Therefore, to ensure accurate color reproduction, it becomes imperative to monitor the dyeing status within the dye solution and continuously detect its concentration in real-time throughout the dyeing process to guarantee optimal printing and dyeing outcomes. Traditional methods for determining dye concentration include titration, gravimetry, density measurement, etc., all of which rely on manual sampling resulting in random errors and limited real-time performance. Currently employed techniques for measuring dye concentration encompass spectrophotometry, fluorescence analysis, high-performance liquid chromatography, and comprehensive flow injection analysis. Among these methods, spectrophotometry stands out due to its exceptional sensitivity levels along with simple operation procedures that are rapid yet non-destructive. However, this technique necessitates expensive equipment that is bulky in size while also demanding high technical proficiency from operators.
In this paper, a device for detecting the concentration of soluble dye solutions was designed based on the fundamental principles of spectrophotometry and C12666MA micro-spectrometer. The device was tested with dye solutions prepared using acid bright red B, acid dark blue 5R, and acid light yellow G to obtain the light intensity of monochromatic light passing through the dye solution. A PLS model was established to detect the concentration of the dye solution in real time using the micro-spectrometer. It was found that the performance of the PLS model based on partial light intensity data ranging from 400 nm to 700 nm outperformed that of a full-band light intensity-based PLS model. The error between the detected concentrations by our device and actual concentrations is less than 5%, indicating high accuracy. Compared to traditional manual methods for concentration detection, our device offers improved automation, simplicity in operation, lower cost, and smaller size.
The current concentration detection device for soluble dye solutions is still in the developmental stage, with limited practical applications. This paper presents an online concentration detection device specifically designed for soluble dye solutions, enabling real-time monitoring of dye solution concentrations. This device ensures the quality of printing and dyeing production while meeting the requirements for intelligent and environmentally-friendly production processes. Moreover, it serves as a valuable reference for the development of automated detection equipment for dye solution concentrations.

Key words: micro-spectrometer, soluble dye solution, concentration, on-line detection, PLS model

摘要： 为了提高纺织印染的染色成功率和自动化水平，设计了一种可溶性染液浓度在线检测装置，选用C12666MA微型光谱仪为检测器模块，STM32F407ZGT6芯片为处理器模块，对酸性大红B，酸性深蓝5R，酸性嫩黄G 3种染液分别进行实验，获取单色光透过染液的光强数据，通过光强数据建立浓度PLS(Partial Least Squares)模型，得到染液的浓度信息。实验结果表明：3种染液测得光强数据绘制成的光谱曲线，与海洋光学USB2000+光谱仪测得光谱曲线基本相同；染液浓度检测值与实际值的相对误差在5%之内，满足印染工厂实际生产的精度需求。该装置相比传统人工检测手段提高了纺织印染过程的自动化水平，保证了印染质量，可实现染液浓度的在线检测，具有重要的应用价值。

关键词: 微型光谱仪, 可溶性染液, 浓度, 在线检测, PLS模型