Microfibre is a synthetic fibre that is microscopic compared to natural fibres. Ultra microfibres are 100 times smaller than a human hair and their star structure give a surface area 40 times greater than conventional cotton fibre. How Does Microfibre Work When Dry? When you drag a dry cloth or dusting head over a surface there are 40 times more fibres generating a positive electrical charge. This positive charge attracts dust which has a negative charge like a huge magnet. The fibres lock in the dust which is not released until proper laundering. How Does it Work damp? Polyamides attract greases and absorb them within their cell walls. Microfibre has the ability to swallow up to ten times it own weight making it great for cleaning as most dirt is carried when soluble in water. The technical term for how microfibre picks up so much dirt and water is capillary vacuum force. Microfibres at the water source first absorb the water before passing it up the cloth to the polyamides.