Breathable Leather Production Process: Stunning Best Guide

  As consumers continue to demand higher levels of comfort, functionality, and environmental friendliness in products such as footwear, furniture, and automotive interiors, traditional artificial leather (PVC, ordinary PU leather) has drawbacks such as poor breathability and stuffy wear, making it difficult to meet the demands of the high-end market. Breathable leather, as a revolutionary combination, finished leather Through its unique physicochemical structure, the material achieves moisture permeability similar to natural leather, while also offering the consistency and workability of synthetic materials, making it a new favorite in today’s market.

The core of the breathable leather production process lies in creating porous, interconnected microstructures that allow water vapor molecules to pass through while liquid water cannot penetrate. Its mainstream production processes mainly include wet processes and subsequent lamination and post-treatment processes.

Wet Base production process

· Step 1: Prepare the base cloth

  · Choose high-quality microfiber nonwoven fabric as the base material. This base fabric is made from island-type or orange-shaped microfibers, and inside it features a complex, interconnected network of micropores, making it a breathable and moisture-permeable ‘highway.’

· Step 2: Slurry preparation

  · Polyurethane (PU) resin is dissolved in solvents such as dimethylformamide (DMF) to form a uniform slurry. Various additives are also added to this slurry, such as fillers, color pastes, stabilizers, and so on.

· Step 3: Impregnation and coating

  · Immersing microfiber nonwoven fabric in PU slurry, or evenly applying slurry onto the base fabric using a coater to ensure full penetration.

· Step 4: Wet Solidification and Porenation (Core Technology)

  · Immerse the base cloth containing slurry into a coagulation bath (usually a mixture of DMF and water).

  · Principle: Because DMF is much more soluble with water than PU resin with water, the water in the solidification bath quickly displaces the DMF in the slurry. PU resin is insoluble in water. During the displacement of DMF, the PU molecular chains undergo phase separation and solidification, forming a three-dimensional network structure filled with micropores inside. This process is called “thermogenesis phase separation.”

  · By precisely controlling the temperature, concentration, and soaking time of the gel bath, the size, distribution, and connectivity of micropores can be adjusted, thereby determining the breathability, tactile feel, and softness of the final product.

· Step 5: Rinse and dry

  · After solidification, the leather blanks (called “bass”) undergo multiple washes to thoroughly remove residual DMF solvents, followed by dimensional drying. At this point, a substrate filled with micropores and with breathable potential is formed.

Composite and breathable layer treatment

To further enhance breathability and provide a comfortable touch, a special breathable layer is usually layered on wet fabes.

· Breathable PU/TPU film lamination: Uses high-tech water-based PU film or TPU (thermoplastic polyurethane) film, which itself contains billions of micropores per square centimeter. The diameter of these micropores is much smaller than that of a water droplet (about 100 microns), but much larger than a water vapor molecule (about 0.0004 microns).

· Through the hot pressing bonding process, this microporous film is tightly bonded with the wet fabe. This thin film forms the first line of defense against liquid water, while ensuring extremely high water vapor permeability.

Post-processing process

This stage mainly gives breathable leather its final appearance, feel, and physical properties.

· Surface treatment: Various styles of treatment agents are applied to the surface through roller coating, spraying, and other methods, such as discoloration effects, drop texture effects, wax finishes, oily finishes, matte finishes, or high-gloss effects. It is worth noting that the formulation and application amount of the treatment agent need to be carefully designed to avoid blocking micropores on the surface that affect breathability.

· Embossing: Using a heated steel roller with patterns to stamp the leather surface, creating a similar effect cow leather and sheepskin, among other natural leathers.

· Drying and cooling: Finally, curing, drying, and cooling are performed to stabilize product performance.