Waterproof Properties Of Outdoor Clothing

The primary function provided by outdoor clothing is waterproofing, and most traditional fabrics are treated with coatings or films for waterproofing. Later, waterproofing treatments using fluorinated compounds or organic silicon as finishing agents emerged. The waterproof effect can be expressed in terms of water resistance and surface moisture resistance.
GB/T4744-1997 "Determination of water resistance of textile fabrics - Static water pressure test" uses the static water pressure borne by the fabric to represent the resistance encountered by water passing through the fabric. That is, under standard atmospheric conditions, one side of the sample is subjected to a continuous increase in water pressure until there are three areas of water leakage. Record the pressure at this time, expressed in kpa or cmh2o. The larger the value, the better the waterproof performance.
The rate of increase in water pressure and the temperature of experimental water are two parameters that affect the results: high temperature will cause the obtained data to decrease; The increase rate of water pressure is too high, resulting in a larger data obtained, while the increase rate of water pressure is small, resulting in results outside the range. Fz/t01004-2008 "Determination of water resistance of coated fabrics" specifies the method for determining the water resistance of coated fabrics when static water pressure is applied within a fixed time cycle. The testing instrument is similar to GB/T4744, but requires a metal mesh above the sample to prevent deformation and bursting. The testing method is to observe whether there is penetration or continue to apply pressure until penetration occurs on one side of the coated fabric sample under specified conditions, when the specified water pressure is reached. For tests with specified pressure values, the evaluation result is either pass or fail. For tests with final hydrostatic pressure values, the evaluation method is the same as GB/T4744.
GB/T4745-1997 "Determination of surface moisture resistance of textile fabrics - Water immersion test" specifies a water immersion test method for determining the surface moisture resistance of various fabrics that have been or have not undergone water resistance or water repellent finishing. Install the sample on the snap ring and place it at a 45 ° angle to the horizontal, with the center of the sample located at the specified distance below the nozzle. Spray the sample with a specified volume of distilled water or deionized water. Determine the water level of the sample by comparing its appearance with evaluation standards and images. The water level is divided into 1-5 levels, with level 1 indicating that the surface is completely wetted, and level 5 indicating that the surface is not wetted and there are no small water droplets on the surface.