Let's first look at some factors that affect the permeability of PTFE fabrics:

1.DWR treatment, permanent water disposal treatment, failure will affect ventilation, good products are similar to everyone, not to say, the second product does not want to say.

2. Outer cloth, who thinks this layer affects ventilation very much, I will say other dishes! By way of example and more intuitively, the GN value is the number of seconds it takes for a pressure of 124mm water column of water to pass 1000cm3 of air through a 1cm2 area. In general, the nylon polyester taffeta fabric we use (not the thick nylon fabric for backpacks), no matter how many T fabrics, its GN value is a few tenths; In this case, water vapor can pass through almost unimpeded, and the GN value of the re-breathable film will be hundreds of times higher, and the moisture permeability resistance (RET value) will be many times higher. Therefore, it is not the main factor affecting the moisture permeability of the laminated fabric.

3. The adhesive layer of the outer cloth and PTFE layer has the same properties as the 6 layers, because the PTFE film has smooth surface, small polarity and difficult adhesion. Different treatments of this layer have certain influence on moisture permeability, but various technologies are not far behind now. China also has many original innovations in this aspect, such as corona radiation treatment, research and development of silicone adhesive and hot soluble polyurethane adhesive, etc.

4.PTFE film layer, as long as the temperature and stretching process are well controlled, the technical difference of this layer is not big, and the opening rate is generally around 80%, so the unprocessed PTFE film is used as the reference for comparison in the previous two pictures. In addition, the thickness of the film also has a certain influence on the moisture permeability, of course, the thin moisture permeability is better.

5.PTFE protective layer, which is the most important layer, because with this layer, the fabric will not lose its effect because of the intervention of body surface grease and detergent. The technical content of this layer is the largest, because this layer has created a situation in which all merchants compete for the waterproof and breathable fabric market. The earliest technology of this layer is to add polyurethane layer to improve, but it seriously affects the moisture permeability. GTX-XCR, fluorine finishing agent is used to treat PTFE surface, and Event also uses 1 molecular level oil repellent agent to improve moisture permeability. This layer is the most important factor that really affects the moisture permeability of PTFE film!

6.PTFE and the inner layer of fabric glue layer, two layers of fabric is not, no longer repeat.

7. The inner protective layer fabric, the two-layer fabric is not available, and there are many technical improvements to this layer, mainly in improving durability and reducing weight.