AQUEOUS POLYURETHANE/POLYUREA DISPERSIONS.

摘要

The present invention pertains to aqueous polyurethane-polyurea dispersions which are prepared by the acetone process using methyl acetate instead of ketones and are chain-extended using hydrazine or derivatives thereof, these dispersions having an improved stabilit y towards thermal yellowing and a relatively low residual hydrazine/hydrazine derivative content.