Outdoor functional fabrics mainly have the following waterproof properties:

1. waterproof coating: outdoor functional fabrics are usually coated, such as polyurethane, fluorocarbon resin, etc. These coatings have good waterproof performance, which can prevent water from penetrating into the fabric.

2. dense weave structure: the weave structure of outdoor functional fabrics is usually dense, which can effectively block the penetration of water and keep the surface of the fabric dry.

3. waterproof and breathable membrane: some outdoor functional fabrics will use waterproof and breathable membrane technology, which can not only prevent water penetration, but also allow the water vapor inside the fabric to be discharged, so as to maintain a comfortable wearing feeling.

4. bonding treatment: some outdoor functional fabrics will be bonded to make the fibers closer to each other, reduce the water permeability of the fabric and enhance the waterproof effect.

5. Water repellent coating: Some outdoor functional fabrics will adopt water repellent coating technology, so that water beads on the surface of the fabric and is not easy to penetrate into the interior of the fabric.

6. Soft and Breathable: In addition to the waterproof function, functional outdoor fabrics also require soft and breathable characteristics, which can provide a comfortable wearing sensation, and can promptly vent out the body steam to keep dry.

Overall, functional outdoor fabrics are essential for outdoor sports and activities as they have a variety of waterproof properties and can effectively resist external water intrusion and protect the wearer from moisture and cold.