Medical mask water repellency tester structure characteristics

The water repellency tester for medical masks is mainly used to test the water repellency of the fabric by comparing the surface of the specimen with the standard chart card to evaluate the water repellency of the fabric surface. It consists of a metal frame allowing distilled water to be sprayed through the nozzle onto the specimen at 45° and 150 mm below the nozzle. The appearance of the specimen is compared to an optional photographic scale.

Conforms to standards:

iso 4920, bs en 24920, bs 3702, gb/t 4745, aatcc 22, m&s p23, nxt 23

Technical features:

1. The instrument is a full metal frame, quantitative distilled water through the standard nozzle at 45 degrees spray below the 150mm to be tested sample, test the surface of the specimen and the standard chart card for comparison, rating;

2. A certain volume of distilled water is sprayed onto the fixed sample ZY, the quality control of the spray hole setting and the precise setting of the height above the sample are to ensure a stable spray water flow and form as strictly required in international standards;

3. The height of the spray nozzle can be set precisely using the provided height setting scale.

Purpose and scope:

1. The standard applies to any textile fabric, regardless of whether it has been made to resist water performance treatment. This standard can determine the fabric resistance to water wetting performance, not suitable for the water repellent performance of textiles, especially plain woven fabrics.

2、Because the instrument is simple and portable, the test procedure is relatively simple, which makes this standard especially suitable for factory product control. Since this standard can not determine the performance of water droplets penetrating into the fabric, it is recommended not to use this standard to evaluate the rainproof fabric penetration performance.

3, the test results of this standard and fiber, yarn and fabric finishing of the initial water repellency and wetting performance, and the fabric structure is not related.

Test principle:

Under the specified conditions, the water is sprayed on a taut specimen to form a wetting pattern on its surface, the size of which is related to the water repellency of the fabric. The evaluation result is to compare it with the standard pattern.

Operation steps:

1, the specimen will be set on a diameter of 152mm metal ring, facing up, to ensure that its surface is flat and wrinkle-free.

2、Place the metal ring with specimen on the tester's shelf, pay attention to the position of the specimen when placing it, make sure the ZX of the ring is exactly aligned with the ZX of the spray pattern ring. for some oblique, beaded or similar striped structure, the direction of the stripes should be placed diagonally with the direction of water flow when the ring is placed on the table.

3. Pour 250ml, temperature 27±1 of deionized water into the funnel of the tester and let it spray onto the specimen in 25-30 seconds time. When pouring deionized water, the beaker should not touch the funnel, if the funnel appears to move will change the pattern, shape, etc. of the sample spraying. Spraying time must be between 25-30 seconds, otherwise the nozzle must be checked to see if the hole is larger or blocked.

4、Hold one side of the ring, turn the specimen face down, and quickly tap the other side towards a hard object, then rotate the specimen 180° horizontally and hold the original tap and quickly tap the original grip again to tap off some of the water droplets on the surface of the specimen that have not been wetted.

5, repeat the above steps to test the remaining two pieces of specimens.

Structural features:

1. Simple structure, consisting of main frame, funnel, nozzle, sample holder and sample holder;

2. The nozzle has 19 evenly distributed holes, and the aperture is customized according to the standard requirements. 250ml of water poured into the funnel can flow out from the nozzle within 25-30s;

3. The surface of the upper edge of the sample holder ring is at an angle of 45° to the horizontal;

4. The distance from the center of the circle where the upper edge of the ring of the sample holder is located, i.e., the distance from the ZX of the sample to the nozzle is 150mm.

2022-12-04 01:03