Abstract: Laser engraving stands as a significant material processing technology, widely employed in the textile and apparel industries due to its distinctive advantages of ease of manipulation, high precision, and cost-effectiveness. Currently, research on laser engraving in household textiles has garnered significant attention, curtains are a crucial component of household textiles, and through laser engraving, they can exhibit a multi-layered three-dimensional effect, thereby enhancing the visual appeal of the indoor environment. However, the high-temperature etching effect during laser engraving may cause penetrating damage to the fabric, thereby impacting the visual privacy of curtain fabrics, which is commonly characterized by transmittance.
To analyze the influence of laser engraving on the structure and transmittance of the fabric, this paper uses different laser engraving parameter combinations (laser power of 3 W, 6 W, 9 W, 12 W, 15 W and 18 W, and laser speed of 500 mm/s, 400 mm/s, 300 mm/s and 200 mm/s) to process cotton and polyester fabrics. First, through microscopic morphological observation using an electron microscope, it was found that the cotton fabric, under the effect of laser thermal energy, exhibited expansion, rupture, and even vaporization removal. The cotton fibers were charred and fell off, yarn cohesion disintegrated, and the interlaced structure of the fabric became looser. The polyester fabric, on the other hand, underwent melting, flowing, and even vaporization decomposition. The fabric surface transitioned from scattered granular polyester to connected bulk polyester, accompanied by fine cracks. On the other hand, the polyester fabric underwent melting and flow, even vaporization and decomposition, with the fabric's surface transitioning from scattered granules of polyester to bonded blocks of polyester accompanied by fine cracks. Following this, Image J software was utilized to standardize the pores at the penetration points of the fabric's transmitted grayscale images for porosity calculation. The number of pores and porosity rate on cotton and polyester fabrics are positively correlated with the laser engraving energy. The transmitted grayscale images showed that the pores in the cotton fabric after laser engraving were approximately shaped like water droplets or ellipses, while those in the polyester fabric were mostly irregular. Both types of pores appeared at the intersections of warp and weft threads. As the laser engraving energy increased, the thickness of the cotton fabric decreased, and the thickness of the polyester fabric initially increased and then decreased, mainly due to the polyester becoming more rigid and harder to compress after laser engraving. Finally, the influencing factors of fabric transmittance after laser engraving were investigated using the gray relational analysis method and correlation theory, and the porosity rate after laser engraving was the primary factor influencing the fabric's transmittance, showing a highly significant positive correlation. The fabric thickness, on the other hand, had an extremely significant negative correlation with the fabric's transmittance.
This study analyzes the action mechanism of laser on fabrics, explores the effects of laser engraving parameters on the structure of fabrics, and studies the relationship among laser mechanism, fabric structure, and transmittance. The findings of this study can serve as reference for the application of laser engraving technology in textiles such as curtains.

Key words: laser engraving, fabric structure, pores, transmittance, grey correlation analysis method, correlation

摘要： 为阐明激光雕刻对织物结构与透光性的影响，选用纯棉、纯涤纶织物，借助电镜观察研究激光在织物上的作用机制；结合织物的孔隙图像处理方法，研究激光雕刻对织物结构的影响；测试织物厚度、质量损失率、透光率的变化，同时利用灰色关联分析法和相关性理论，研究激光雕刻后织物结构参数对透光性的影响。结果表明：激光使棉织物产生膨胀与破裂乃至汽化去除，使涤纶织物熔融流动甚至汽化分解；棉、涤纶织物上的孔隙数量和孔隙率与激光雕刻能量呈正相关，随着激光雕刻能量的增大，棉织物厚度下降，涤纶织物的厚度则是先增加后减少；激光雕刻后织物孔隙率、厚度与透光性之间呈强关联性，其中孔隙率为透光性的第一影响因素，织物透光性与孔隙率呈极显著正相关，与厚度呈极显著负相关。研究结果为激光雕刻技术在窗帘等类型纺织品的应用提供参考。

关键词: 激光雕刻, 织物结构, 孔隙, 透光性, 灰色关联分析, 相关性