Waterproof bag function:
1. The waterproof function comes from its fabric. Generally, the fabric surface is treated with waterproof agent, or coated with plastic, PU, PVC, PA, etc. to make the fabric waterproof. When testing whether the waterproof bag has waterproof coating, the fabric can be tested with water on site. If there are obvious water drops on the fabric after watering, it is a waterproof bag.
2. After understanding the waterproof fabric, we come to understand the waterproof functional strength of the waterproof bag. We need to know the waterproof index of the fabric. The standard of waterproof bag is water pressure resistance - how many mm water column can be withstood per square centimeter area, and it is impermeable for one hour. Generally, the waterproof degree of waterproof nylon is 1000-2000mm, which can withstand short-term rain and 5000mm long-term rain. The key point of all waterproof indexes is not how much water to prevent, but the pressure and time of water. The simple understanding is that in natural conditions, the size and speed of raindrops and the time of exposure to rain will cause different waterproof effects.
3. The durability of waterproof bag is to experience the multiple tests of time, high torture and pressure, so it is important to find a light and wear-resistant material! In addition, if the contact point between the strap and the main body of the waterproof bag is not strong enough, attention should also be paid to the following aspects: the firmness of the sewing thread of the waterproof bag itself, the strengthening treatment of the zipper and the opening, and the strengthening double-layer treatment of the bottom of the waterproof bag.
