What Is The Water Vapor Transmission Rate of PVC Coated Fabric?

Introduction

As we all know, PVC coated fabrics have excellent waterproof performance. It is precisely because of this characteristic that PVC coated fabrics can be widely used in fields such as tents, waterproof fabrics, industrial protective clothing, and inflatable products. However, many people have overlooked a key performance indicator - water vapor transmission rate. This parameter directly affects the applicable scenarios and service life of the finished product. Today, let's take a look at these easily overlooked product parameters.

What is water vapor transmission rate?

Water vapor transmission rate (WVTR) refers to the mass of water vapor passing through a unit area of material within a unit of time (usually expressed as g/m²/24h). The lower the value is, the better the waterproof sealing property of the material is. The higher the value, the stronger the air permeability of the material.

For finished products with high sealing requirements (such as tarpaulins and liquid storage tanks), the lower the water vapor transmission rate, the better, to prevent water vapor penetration from causing internal corrosion or contamination. Conversely, for finished products that require ventilation (such as protective clothing and agricultural greenhouses), the water vapor transmission rate should be increased accordingly to prevent condensation or stuffiness inside.

It must be noted that one must first understand the requirements of the finished product and then select the appropriate PVC coated fabric. If the wrong materials are selected, it may lead to the product getting moldy in a humid environment (with a WVTR too high), or accumulating moisture in a high-temperature sealed environment (with a WVTR too low).

Conclusion

The water vapor transmission rate is not necessarily the higher or lower; rather, it needs to be precisely matched with the usage environment of the terminal product. Newstar suggests that you provide specific application scenario parameters (such as temperature and humidity, mechanical strength requirements, etc.), and we will offer you the most suitable PVC coated fabric. If necessary, you can request a customized formula.