Key Processes and Technologies for Enhancing the Strength of PVC Coated Fabrics

Introduction

PVC coated fabrics are widely used in construction, transportation, outdoor equipment, and other fields due to their excellent waterproof, wear-resistant, and corrosion-resistant properties. However, PVC coated fabrics produced by traditional processes have certain limitations in terms of strength and durability. Improving the strength of PVC coated fabrics is crucial, and manufacturing processes play a vital role. Optimized knife-coating processes, vertical fiber array modification technology, TPU and PVC blend coatings, and surface treatment technologies are all key processes for enhancing strength.

Key Processes for Enhancing the Strength of PVC Coated Fabrics

1. Optimization of the Knife-Coating Process

The knife-coating method is one of the most efficient and widest-width processes currently used in the production of PVC coated fabrics. Its core principle is to uniformly coat the base fabric surface with liquid PVC paste using a doctor blade, followed by high-temperature plasticization to form a dense coating. Base fabric selection: Using base fabrics woven from high-strength, low-shrinkage industrial fibers (such as polyester and aramid) can significantly improve the overall strength of the fabric. For example, Hubei Jinlong Company uses 1140D high-strength fiber base fabric, resulting in a tensile strength of over 3500N for the coated fabric.

Slurry ratio: The reasonable ratio of PVC paste resin to plasticizers (such as DOP and DOA) is crucial. Adding fillers such as nano-calcium carbonate can enhance the hardness and wear resistance of the coating.

Process control: The coating thickness needs to be controlled at 35-55S (approximately 400-650g/m²), and multiple coating passes are required to ensure coating uniformity and prevent peeling or cracking.

2. Vertical Fiber Array Modification Technology

By implanting vertically arranged short fibers (such as PA and carbon fibers) on the coating surface using an electrostatic flocking process, a "pin structure" is formed, which can significantly improve wear resistance and peel strength. Fiber selection: Short fibers with a length of 0.5-1.2mm can be uniformly embedded in the coating, enhancing interfacial bonding. Experiments show that the peel strength of coated fabrics modified with 1.2mm fibers increased by 220%. Process Steps: Base fabric pretreatment → Bottom coating → Electrostatic flocking → Top layer lamination. After flocking, it needs to be dried and cured at 170℃ to ensure a strong bond between the fibers and the coating.

3. TPU and PVC Blended Coating Technology

Introducing thermoplastic polyurethane (TPU) into the PVC coating combines flexibility and wear resistance, solving the problem of aging and embrittlement of traditional PVC coatings. Blending process: TPU powder (particle size 400-800 mesh) is evenly attached to the surface of the PVC coating through a vertical forced-air dryer, forming a "sea-island structure." This method allows for flexible adjustment of TPU content (10%-25%) to meet different performance requirements.

Performance advantages: The addition of TPU increases the weather resistance of the coating by more than 30%, while also increasing the tear strength by 15%-20%.

Auxiliary Technologies: Surface Treatment

1. Surface Functionalization Treatment

Self-cleaning coating: Adding nano-titanium dioxide (TiO₂) or graphene gives the coating UV resistance and anti-fouling properties, extending its service life.

Flame retardant treatment: Introducing brominated flame retardants or phosphorus-nitrogen synergistic systems allows the fabric to meet the UL94 V-0 fire resistance standard.

2. Equipment Upgrades and Process Parameter Control

Wide-width production line: Using a four-coating, three-drying process, it supports a width of up to 3.8 meters, producing high-density (1500g/m²) coated fabrics in a single pass.

Precise temperature control: Drying temperature needs to be controlled in stages (e.g., 140℃→180℃→240℃) to avoid over-melting or incomplete plasticization of the coating.

Conclusion

Through the combination of the above processes and technologies, PVC coated fabrics can achieve breakthroughs in strength, durability, and functionality. As a professional PVC coated fabric manufacturer, we will select the appropriate solution based on specific needs. In addition, we also focus on equipment upgrades and environmental trends to ensure a competitive advantage in the fierce market competition.