The effect of three handheld ultrasonic devices for the pretreatment of stains on textiles was evaluated under household conditions. Twenty soiled textiles were treated and the mean increase of lightness Δ L * of the soiled textiles was used as a measure for the cleaning effect. It was shown that the combination of a pretreatment and a washing cycle at 20 °C yields a higher mean increase of lightness, Δ L * = 19.5, compared to a 40 °C washing cycle without pretreatment, Δ L * = 15.3. The effect is most pronounced for mixtures consisting of oily soils with pigments, Δ L * = 25.1. During the pretreatment, the soil was soaked in a detergent solution and the effect of soaking was measured separately.

中文翻译：

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超声波预处理污渍在家用洗衣店清洗中的效果

在家用条件下评估了三种手持式超声波设备对纺织品污渍进行预处理的效果。对 20 件被污染的纺织品进行处理，并将被污染的纺织品的平均亮度增加 Δ L * 用作清洁效果的衡量标准。结果表明，与没有预处理的 40°C 洗涤循环 ΔL * = 15.3 相比，预处理和 20°C 洗涤循环的组合产生更高的平均亮度增加，ΔL * = 19.5。对于由油性土壤和颜料组成的混合物，效果最为明显，Δ L * = 25.1。在预处理过程中，将土壤浸泡在洗涤剂溶液中，并分别测量浸泡效果。