Waterproof performance refers to the resistance of fabrics to be wetted and infiltrated by water. There are three characterization indexes of waterproof performance of fabrics, i.e. water level, hydrostatic pressure level and water penetration. There are two test methods, i.e. spray method and hydrostatic pressure method.
Spray method
The spray method is to carry out the spray test on the sample under certain conditions, and determine the water level according to the water situation, so as to evaluate the waterproof performance of the fabric.
Spray method is used to simulate the degree of wetness of fabrics when they are exposed to rain. It is suitable for fabrics with or without waterproof treatment. The wettability measured by spray method is related to the fiber, yarn, structure and surface performance of fabrics.
Common standards
GB / T 4745, ISO 4920, jisl1092, AATCC 22 and BS 3424-26 determine the water-proof property of the fabric by the spray test. After the spray test of the sample under certain conditions, the water-proof grade or fraction of the fabric is determined by comparing the appearance of the sample with the description of the water-proof phenomenon and the pictures. JIS l1092 also specifies the determination of water absorption and water absorption.
AATCC 35, AATCC 42 and ISO 9073-17 put a piece of weighed absorbent paper after the test sample, spray with water under the specified conditions, and then weigh the weight of the absorbent paper again to evaluate the water permeability of the sample. This method is mainly used to predict the rain water resistance of fabrics. Among them, ISO 9073-17 is specially for the determination of water penetration resistance of non-woven fabrics.
GB / T 14577 and ISO 9865 bondermen method are used to evaluate the water repellency of fabrics under the action of shower. Specifically, under the designated man-made rain shower, the resistance of the fabric to rainwater absorption is tested after the specified time, expressed by the water repellent grade, and the water absorption and water flow through the fabric can also be evaluated.
Hydrostatic pressure method
Hydrostatic method refers to the permeability of fabric under a certain water pressure. The hydrostatic pressure on the fabric indicates the resistance of water through the fabric. The hydrostatic pressure of the fabric is related to the fiber, yarn, fabric structure and surface performance. There are two methods to test the water resistance of the fabric, static pressure method and dynamic pressure method.
Common standards
GB / T 4744, ISO 811, en 20811, aatcc127, JIS l1092, as 2001.2.17, ASTM D751, ISO 9073-16 represent the resistance of water through the fabric by the hydrostatic pressure on the fabric. The test principle is that under certain conditions, one side of the sample is subjected to continuously rising water pressure, and the pressure value when certain penetration occurs is recorded, so as to evaluate the waterproof performance of the fabric. Among them, ISO 9073-16 is specially for the determination of water penetration resistance of non-woven fabrics.
FZ / T 01004, ISO 1420 and BS 3424-26 are applicable to coated fabrics. Under the specified conditions, one side of the sample to be tested is subjected to continuously rising water pressure until the specified water pressure value is reached. Observe whether there is penetration or continuous pressure until penetration occurs within the specified time.
