NMP-free polyurethane products for the leather industry: a new challenge for finishing

摘要

Polyurethanes (PUs) have played a key role in numerous fields of application for many years. Their property profile can be adjusted to suit a particular application by selecting the appropriate components. For example, soft or hard segments can be incorporated into the polymer chains, making the film hardness and the adhesion properties more or less infinitely adjustable. PU coatings have good flex resistance, even at low temperatures, and generally also have a relatively high melting point. High quality properties are thus ensured making PUs the ideal product whenever lacquers or coatings are required. The outstanding film-forming properties of PU dispersions are particularly valuable in the leather finishing, providing homogeneous, long-lasting coatings with good aging resistance. These finishes can be easy-care, have good adhesion and flex resistance, and a high level of wear comfort. Even better physical fastness properties can be obtained if the finish is crosslinked. PUs can be effectively combined with other materials such as acrylics.