June 18, 2021
Are the clothes you wear qualified for perspiration?
Sweating is a necessary physiological function to help the body cool down and prevent it from getting too hot. However, the sweat stains on your clothes are ugly, which may embarrass you, and can make people feel hot, humid and uncomfortable. If you like sports, then moisture wicking clothes are your first choice.
The way clothes absorb moisture and wick away sweat
Clothes absorb moisture and wick away sweat, so that they will not be soaked by sweat. In order to improve the humidity comfort of clothes, we must first understand the process of sweat permeating through fabrics. Under normal circumstances, the transfer process of sweat in the fabric is roughly composed of three steps: moisture absorption, diffusion, and quick drying.
In all the above, sweat passes through the outer surface from the inner surface of the clothes in two ways, liquid phase and gas phase.
Water vapor transmission - water vapor transfer
The water vapor permeability of the fabric is generally expressed by the amount of water vapor permeated per unit time per unit area under the condition that there is a certain relative humidity difference between the two sides of the fabric. Under the humidity gradient, water vapor diffuses from the high-humidity air through the fabric to the low-humidity air. The movement of water vapor depends on the porosity of the textile material and the structural voids in the fabric. This porosity and voids are interconnected to form channels. It can pass water vapor to escape the surface of the fabric.
Liquid phase transfer of water-transfer of liquid water
When liquid water meets the fabric, the fibers in the fabric absorb water. Different fibers absorb water differently. For example, hydrophilic fibers contain more hydrophilic groups and have greater water absorption capacity, while hydrophobic fibers are the opposite, so the water absorption effect is poor. This water absorption of fiber is generally called liquid water management performance. In addition, a wicking effect occurs between the fabric and the liquid water. The water is transferred to the surface of the fabric along the capillaries of the fabric and evaporates in the surrounding air layer.
Fabric moisture permeability test evaluation
Reference test standard: ASTM E96, put the moisture-permeable cup filled with moisture absorbent or water and sealed with fabric sample in the moisture permeability tester (a closed environment with specified temperature and humidity), according to the quality of the moisture-permeable cup within a certain period of time Calculate the moisture vapor transmission rate.
Fabric moisture permeability tester used to determine a variety of textile and apparel fabrics, coated fabrics, composite materials, moisture permeability sportswear and industrial fabrics. The tester equipped with a touch panel, and can be programmed to control the test.
The fabric moisture permeability test is divided into four steps
1. Prepare the assembly (sample, medium, moisture-permeable cup).
2. Place the combination in the required temperature and humidity conditions to balance, and after reaching the balance time, weigh M1.
3. Put the sample weighed for the first time into the selected temperature and humidity environment, and after the test time is up, weigh M2.
4. Record and report the average results of the three test samples. The moisture permeability tester can use a variety of methods to effectively test the moisture permeability of the fabric and provide a strong basis for fabric comfort.
The moisture permeability of the fabric is an important parameter for the comfort of the clothes. If the sweat and water vapor can pass through the clothes smoothly, people will not feel the presence of moisture, but if the clothes severely obstruct the passage of water vapor, the water vapor in the clothes will accumulate to a certain extent. People feel uncomfortable when it condenses into water.