The core suction method is the most common and simple method to directly test the water absorption of fabrics. The test sample is usually cut into strips. One end of the test sample is suspended on the iron shelf and the other end touches the water surface (or is immersed in water at a certain height). After immersion for a certain period of time (f), the height (h) of water climbing through the capillary tube and fiber pores of the fabric is measured. Fabric with good water conductivity, strong water absorption, water absorption speed (that is, core absorption speed) fast, unit time climbing height is large, that is, high water conductivity. If during the test, due to the relationship between fabric structure, fiber, yarn and color, the climbing process of water is not obvious, and the naked eye cannot observe it well, you can add a little colorant to the water.
The core absorption rate (v) depends on the physical and chemical properties of the fiber and the thermal equilibrium process of liquid molecules. Macroscopically, it depends on the shape and direction of pores. The core suction velocity is the height value of water rising per unit time, that is, v(cm/s)=h/t. The strength of water conductivity is related to the core suction speed. Therefore, the core absorption can be used to test the water conductivity of the fabric.