The spray method is to continuously spray water or drip water onto the sample, observe the characteristics of water stains on the surface of the sample after fixed time, and compare with the samples of various wetting degrees to evaluate the waterproof property of the fabric. The spray method simulates the degree to which clothes get wet when they are caught in a drizzle. This method is applicable to all fabrics with and without waterproofing treatment. The waterproofing results are greatly related to the fiber, yarn, fabric treatment and fabric structure.
Spray type water repellent performance tester is usually used to determine. In the AATCC 22-2005 test method, the test sample was fixed with an iron ring with a diameter of 152.4mm, and the sample was in a tensioning state with a flat surface and no wrinkles. Spray 250mL distilled water at 45° from the standard nozzle to sample at 150mm below the nozzle for a spraying time of 25 ~ 30s. The bottom of the ring with the sample is tapped once for the solid object, and the test surface is opposite to the solid object. Then the ring is rotated 180° and tapped once, and the sprayed sample surface is compared and rated with the standard chart card to evaluate the water resistance of the fabric. There are five levels of evaluation, with 5 being the best and 1 being the worst. Level 5 -- no water droplets on the test sample surface; Level 4 - slight wet spots on test surface; Level 3 -- there are obvious drops of rain on the test sample surface; Level 2 - partial wetting on test surface; Level 1 - all sample surfaces tested are wet.