Is the base fabric of flame-retardant PVC-coated fabric also flame-retardant?

Introduction

Flame-retardant PVC-coated fabric plays a key role in applications ranging from industrial protective equipment, building sunshades, tents, vehicle interiors, and public space decoration. However, when choosing this type of material, many people often wonder: Is the base fabric itself flame-retardant?

What is flame-retardant PVC-coated fabric?

Flame-retardant PVC-coated fabric is a composite material treated through a special process. It consists of two main components: a base fabric (the base fabric) and a PVC coating (the surface treatment layer). The base fabric is typically made of polyester fiber (polyester), glass fiber, or cotton. The PVC coating is a polyvinyl chloride (PVC) resin coated on the base fabric surface, along with chemical additives such as plasticizers, stabilizers, and flame retardants to enhance its fireproofing, water resistance, and abrasion resistance.

The flame-retardant properties of the coating primarily rely on the flame retardants in the coating. These chemicals can inhibit the spread of flames, reduce the burning rate, and even cause it to self-extinguish when exposed to fire. But does this mean that the base fabric is also flame-retardant? The answer is not absolute.

The flame retardancy of the base fabric is often overlooked.

In fact, the flame retardancy of the base fabric is one of the core factors determining the overall fire rating of the material. If the base fabric itself is not flame retardant, even if the PVC coating has excellent flame retardant properties, it may still ignite, carbonize, or even burn when exposed to open flames or high temperatures, causing the entire material to fail.

If the base fabric of the PVC-coated fabric is a non-flame retardant material (such as ordinary polyester or cotton), once the fire penetrates the coating, the base fabric will become fuel, posing a safety hazard.

Therefore, high-quality flame-retardant PVC-coated fabrics typically use an inherently flame-retardant base fabric or a flame-retardant treatment. Common practices include:

Using inherently flame-retardant fibers: such as glass fiber, aramid, and modified polyester (flame-retardant polyester). These fibers have high melting points or are flame-retardant, effectively resisting flames even without a coating.

Flame-retardant treatment of the base fabric: Flame retardants are incorporated into the fibers through padding, spraying, or chemical grafting, imparting lasting flame retardancy. For example, cotton base fabrics are often treated with phosphorus- or nitrogen-based flame retardants.

Conclusion

In summary, the base fabric of flame-retardant PVC-coated fabrics is not necessarily flame-retardant, but its flame retardancy directly impacts the safety of the overall material. When purchasing, be sure not to focus solely on the coating and ignore the base fabric.