1 Medical adhesive tape water vapor permeability testing device
A box made of anti-corrosion material, with external dimensions approximately 95 mm × 25 mm × 20 mm, and a net weight not exceeding 60 g. Except for a rectangular opening of 80 mm × 10 mm at the top, the rest is completely sealed. Apart from the opening (which is covered with the test material), the box is completely impermeable to water or water vapor.
The material used for the water vapor permeability device of the medical adhesive tape produced by Shandong Provincial Textile Science Research Institute is stainless steel.
2. Test Procedure for Water Vapor Permeability of Medical Adhesive Tape
Place a plate containing approximately 1 kg of anhydrous calcium chloride into an electrically heated drying oven equipped with a circulating air system, maintaining the temperature at 36℃ to 38℃. Take five small boxes that meet the above requirements, each containing approximately 2 g of absorbent cotton, and each pouring approximately 20 mL of water. Cover the open top with a test strip of the test material, press the material without allowing it to stretch, and ensure that the opening is completely sealed. Ensure that the wet absorbent cotton does not come into contact with the lower surface of the test material. The width of the material must be at least 5 mm larger than the opening size.
Weigh the sealed boxes to the nearest milligram. Place them in the cabinet for approximately 18 hours (record the time to the nearest 15 minutes). Remove the boxes from the cabinet. Cool them for 1 hour under standard atmospheric pressure. Weigh them again to the nearest milligram.
3 Results Presentation
The water vapor permeation for each 24 hours was calculated based on the opening area at the top of each box and the mass loss. It was expressed in grams per square meter (g·m-2). The water vapor permeation of the medical tape for each 24 hours should be no less than 500 g·m-2.
