Right radical 刂 is the side form of 刀, the indexing radical for 刷. Scrubbing involves no real blade; the knife stands for any sharp, repetitive scraping against a surface. The same radical drives 切, 删, 划, 列.
Top-left 尸 is a person leaning forward, here a body bent over a task: scrubbing, sweeping, brushing. With the cloth 巾 underneath, the picture is someone hunched over with a wiping rag in hand.
Lower-left 巾 is a hanging cloth or rag, the cleaning tool itself. Tucked under the body 尸 it pictures the wipe-cloth being applied. The same component is the brushy element in 帚 and 帜.