AATCC 195-2020 Test Method for Liquid Moisture Management Properties of Textile Fabrics.
2. Principle
2.1 The liquid moisture management properties of a textile are evaluated by placing a fabric specimen between two horizontal (upper and lower) electrical sensors each with seven concentric pins. A predetermined amount of test solution that aids the measurement of electrical conductivity changes are dropped onto the center of the upwardfacing test spec- imen surface. The test solution is free to move in three directions: radial spreading on the top surface, movement through the specimen from top surface to the bottom surface, and radial spreading on the bottom surface of the specimen. During the test, changes in electrical resistance of specimen are measured and recorded.
2.2 The electrical resistance readings are used to calculate fabric liquid moisture content changes that quantify dynamic liquid moisture transport behav- iors in multiple directions of the specimen. The summary of the measured results are used to grade the liquid mois- ture management properties of a fabric by using predetermined indices.
3. Terminology
3.1 absorption rate (AR T ) (top sur- face) and (AR B ) (bottom surface), n.— the average speed of liquid moisture absorption for the top and bottom surfaces of the specimen during the initial change of water content during a test.
3.2 accumulative one-way transport capability (R), n.—the difference between the area of the liquid moisture content curves of the top and bottom surfaces of a specimen with respect to time.
3.3 bottom surface (B), n.—for test- ing purposes, the side of the specimen placed down against the lower electrical sensor which is the side of the fabric that would be the outer exposed surface of a garment when it is worn or product when it is used.
3.4 maximum wetted radius (MWR T ) and (MWR B ) (mm), n.—the greatest ring radius measured on the top and bottom surfaces.
3.5 moisture management, n.—for liquid moisture management testing, the engineered or inherent transport of aque- ous liquids such as perspiration or water (relates to comfort) and includes both liq- uid and vapor forms of water. 3.6 overall (liquid) moisture management capability (OMMC), n.—an index of the overall capability of a fabric to transport liquid moisture as calculated by combining three measured attributes of performance: the liquid moisture absorption rate on the bottom surface (AR B ) , the one way liquid transport capa- bility (R), and the maximum liquid mois- ture spreading speed on the bottom sur- face (SS B ) .
3.7 spreading speed (SS i ), n.—the accumulated rate of surface wetting from the center of the specimen where the test solution is dropped to the maximum wetted radius.
3.8 top surface (T), n.—for testing purposes, the side of a specimen that, when the specimen is placed on the lower electrical sensor, is facing the upper sensor. This is the side of the fabric that would come in contact with the skin when a garment is worn or when a prod- uct is used.AATCC 195 pdf download.