What are the common base fabric materials used in PU/PVC leather for sofas

The exceptional performance of sofa-grade PU (Polyurethane) and PVC (Polyvinyl Chloride) synthetic leather is determined not only by its surface coating but crucially by its underlying support structure—the Substrate Fabric. Serving as the synthetic leather's "backbone," the substrate directly influences the material's mechanical strength, dimensional stability, hand-feel, breathability, and cost structure. Selecting the appropriate substrate material and organizational structure is vital for ensuring the final sofa product possesses premium quality and long-term durability.

Knitted Substrates: The Ideal Choice for Flexibility and Resilience

1. Warp Knit Fabric (Tricot)

Warp knit fabric, often referred to as Tricot, is the most common type of knitted substrate used in the sofa leather industry. It forms loops along the warp direction, resulting in a dense structure with inherent elasticity.

Technical Advantages and Application:

• High Flexibility and Drape: The loop structure of warp knit fabric imparts excellent flexibility and a desirable drape to the synthetic leather. This ensures the material conforms smoothly and naturally when upholstering a sofa, effectively preventing severe wrinkles or stiffness.

• Superior Tear Resistance: Despite being a knit structure, its tight loop formation provides good tear resistance, allowing it to withstand localized stresses encountered during daily sofa use.

• Aesthetic Alignment: It is suitable for modern, minimalist sofas seeking a lightweight and soft hand-feel. When combined with wet-process PU or solvent-free PU coatings, it maximizes the leather's delicate texture.

2. Weft Knit Fabric

Weft knit fabrics, such as jersey or rib knits, are typically reserved for specific sofa sections or models demanding higher extensibility.

Technical Advantages and Application:

• High Extensibility: Provides bi-directional or four-way stretch capability. This is particularly effective for oddly shaped, curved, or complex sofa designs that require the material to conform tightly to contours.

Woven Substrates: Guaranteeing Strength and Stability

Woven fabrics are created by interlacing warp and weft yarns, renowned for their high strength and low elongation. In sofa leather applications, they are mainly used where extreme support is required for heavy-duty or structural functions.

Technical Advantages and Application:

• Excellent Dimensional Stability: The woven structure is highly stable and resists stretching or deformation, ensuring that the leather on large sofas or high-stress areas remains flat and taut over time, avoiding sagging.

• High Tensile Strength: Offers superior resistance to stretching and breaking compared to knitted fabrics, making it suitable for high-intensity use in public area seating or commercial furniture.

• Bulk and Support: Ideal for pairing with thicker PVC coatings to create the robust, solid appearance characteristic of traditional or classic style sofas.

Non-Woven Fabrics: Balancing Uniformity, Tactile Feel, and Cost

Non-woven fabric is manufactured by mechanically, thermally, or chemically bonding a fiber web, where fibers are arranged randomly or directionally. Its use is increasingly prevalent in synthetic leather, especially in high-quality PU leather.

Technical Advantages and Application:

• High Uniformity and Delicate Hand-Feel: Lacking distinct warp/weft lines, non-woven substrates lend a more uniform and refined tactile sensation to the synthetic leather surface. This is essential for Microfiber Leather, which aims to closely mimic the luxurious feel of genuine leather.

• Precise Thickness and Density Control: The density and thickness of non-woven fabrics can be accurately controlled, providing appropriate cushioning and support, thereby enhancing the overall fullness of the finished leather.

• Eco-Friendly Options: Certain new non-woven substrates, such as those made from recycled PET fibers or bio-based fibers, align with green procurement trends and sustainable development market demands.

Composite Substrates: Performance Stacking and Optimization

To achieve more complex performance objectives, the industry frequently utilizes Composite Substrates, which involve combining two or more substrate types (e.g., knit and non-woven) using adhesive or lamination technology.

Technical Advantages and Application:

• Complementary Performance: Composite substrates can simultaneously leverage the uniform, delicate hand-feel of non-woven material and the excellent elasticity of knit fabric, or the robust support of woven fabric, achieving a synergistic effect where "1+1 > 2" in performance.

• High-End Customization: Suitable for the premium, custom-made sofa market where performance requirements are stringent, offering broader design freedom and functional assurance.

Quality Control: Substrate's Impact on the Final Product

In the synthetic leather manufacturing process, the substrate's fiber composition, density (gram weight), and thickness uniformity are critical quality control metrics. Instability in the substrate can lead to final product issues like dimensional shrinkage, coating delamination, and insufficient strength. Therefore, careful selection and quality control of the substrate are crucial for ensuring the durability, comfort, and cost-effectiveness of PU/PVC synthetic leather. The application of high-quality substrates significantly elevates the overall performance of the synthetic leather, guaranteeing long-term reliability and aesthetic appeal in sofa applications.