Two-component polyurethane sealants, a process for preparing them and their use for bonding a windscreen.

摘要

Two-component polyurethane sealants, comprising (A) a pasty polyurethane component containing a polyurethane prepolymer having free isocyanate groups, and a curing agent, and (B) a pasty solvent-containing component, where component (A) contains at least one latent, solvent-activatable curing agent which can be activated by means of solvents, and component (B) contains a polar, aprotic solvent and water reversibly bonded to a carrier substance which liberates water in a delayed manner after components (A) and (B) have been mixed. They are prepared by mixing components (A) and (B) using a static mixer, having only from 15 to 75 % of the number of mixing elements necessary for achieving homogeneous mixing of components (A) and (B) in the ratio by volume of 1:1. Application to a method for bonding a windscreen.