The test sample should be adjusted for at least 16 hours under the condition of (21±2)℃ and relative humidity (RH) of (60±15)%. And test under the same conditions.
instrument
1 Water resistance measuring instrument: There is a pool that can apply 500mm hydrostatic pressure for 300s to the circular area of the non-adhesive surface of the test material. The sample is fixed in a horizontal position with two rings, and the lower ring is an integral part of the tank. The screw device is used for clamping to prevent leakage and sample movement during the test. The hydrostatic pressure is generated by a vertical pipe connected to the bottom of the pool with an inner diameter of not less than 3mm.
To prevent leakage, the annular surface in contact with the sample should be covered with a suitable covering material, such as rubber.
2 Distilled water, deionized water.
3 steps
3.1 The prepared sample should be free of wrinkles.
3.2 Fill the pond with purified water at (21±2)℃.
3.3 Place the sample on the lower ring in a horizontal sliding manner to avoid air between the water surface and the lower surface of the sample.
3.4 Cover the upper surface of the sample with dry filter paper larger than the test area, put on the upper ring, and clamp it with a screw device.
3.5 Fill the tube with water to reach the required water level above the sample surface.
3.6 Maintain the hydrostatic pressure (300 ± 10) s.
3.7 Check whether there is water seeping through the sample on the filter paper and record the result.
The LFY-244D medical material Waterproofness tester produced by Shandong Textile Research Institute meets the standard YY/T 0471.3-2004 Test methods for primary wound dressings Patrt 3 - Waterproofness
The LFY-244D medical material Waterproofness tester