关键词: 洗干一体机, 纯棉衬衫, 外观平整度, 织物运动, 蒸汽熨烫

Abstract: Washer-dryers are suitable for modern family living scenarios featuring a fast pace and limited space. However, cotton fabrics are prone to wrinkling after being washed and dried in such appliances, which seriously impairs consumers' wearing experience. To realize the integrated "washing-drying-ironing" care of fabrics in washer-dryers, this study explores the influencing factors and rules of wrinkling of pure cotton shirts in washer-dryers through systematic experiments, and proposes three methods including mechanical force (rotation speed and rotating frequency), staged variable temperature, and high-temperature steam care to improve the smoothness appearance of fabrics after drying. A comprehensive drying monitoring platform integrating "temperature‒humidity-moisture content‒fabric movement" was established, and full-factor experiments on rotation speed and rotating frequency, staged variable temperature experiments, and in-machine high-temperature steam care experiments were designed to analyze the wrinkling factors of pure cotton shirts during the drying process and explore the optimal wrinkle removal parameters. The fabric wrinkling rules show that rotation speed and rotating frequency directly affect the post-drying smoothness of fabrics by regulating the fabric movement state, spatial distribution characteristics inside the drum, and residence accumulation time; temperature and humidity cause uneven release of internal stress in fibers by changing the fiber moisture evaporation rate and shrinkage behavior, which further leads to fabric wrinkling; high-temperature steam can release internal stress through hydrothermal plasticization, promote the sliding of yarns and fibers, and reorganize a stable hydrogen bond network to eliminate wrinkles. The results of fabric wrinkle removal show that the optimal rotation speed for fabric smoothness optimization is 55 r/min, which can improve the smoothness by 1.2 grades; the optimal rotating frequency is 27 s/3 s, which can increase the smoothness by 0.3 grades; reducing the drying temperature to 60 ℃ when the fabric moisture content drops to 30% can improve the smoothness by 0.5 grades; introducing 10 min of steam (the ironing speed is 48 g/min) 20 min before the end of drying and continuing drying for another 10 min can enhance the smoothness by 0.5 grades. Through the above three schemes, the smoothness of a single pure cotton shirt after drying can be increased from 1.1 grades to 3.5 grades, achieving an ironing-like effect. The efficient wrinkle removal technology developed in this study is applicable to washer-dryers, realizes the integrated "washing-drying-ironing" care of shirts in household small-load scenarios, and provides theoretical support and process references for the functional development of household appliances.

Key words: washer-dryer, cotton shirt, smoothness appearance, fabric movement, steam ironing