Surface Finish
Polymer layers applied to the surface of a textile substrate provide water resistance and a specific aesthetic finish. In the manufacturing of synthetic leather and technical apparel, polyurethane coatings create a protective barrier that can be engineered for breathability or high abrasion resistance. These finishes are widely used in everything from raincoats to upholstery.
Application Technique
Liquid resins are spread onto the fabric using a knife-over-roll coater or a transfer paper system. Once applied, the polyurethane coatings undergo a curing process involving heat or chemical cross-linking to form a solid film. This bond between the polymer and the fibre determines the final peel strength of the material.
Performance Characteristics
Engineers adjust the chemical formulation to achieve different levels of hardness, flexibility, abrasion resistance and UV resistance. For example, thin polyurethane coatings on lightweight nylon create a packable waterproof jacket, while thick layers on heavy canvas are suitable for industrial tarpaulins. Breathable versions contain microscopic pores that allow water vapour to escape while blocking liquid droplets from entering.
Quality control involves testing for hydrostatic head, air permeability and resistance to cracking at low temperatures. These tests ensure that the coated fabric meets the performance requirements of the end user.
Environmental Care
Water-based dispersions are replacing solvent-based systems to reduce the emission of volatile organic compounds in the factory. This shift in polyurethane coatings technology supports cleaner production goals in the textile industry. It remains a versatile solution for fabric enhancement.
