| Bayhydrol® UH 2558 | Covestro | Bayhydrol® UH 2558 is a cosolvent-free aliphatic, anionic polyurethane dispersion used as a binder in the formulation of water-reducible coatings and sealers. This product has a non-volatile content (1g / 1h / 125°C) of 35-39, an Efflux time at 23°C, (4mm...view more Bayhydrol® UH 2558 is a cosolvent-free aliphatic, anionic polyurethane dispersion used as a binder in the formulation of water-reducible coatings and sealers. This product has a non-volatile content (1g / 1h / 125°C) of 35-39, an Efflux time at 23°C, (4mmcup) of max. 40, and a pH (1:3 in demineralised water) value of 7-9. The product is characterized by high resistance to yellowing, very good wet film transparency and very good abrasion resistance (taber), where the films are hard but flexible. Post-curing of such coatings with Bayhydur®, for example, brings additional significant advantages and results in waterborne two-component coatings with significantly higher mechanical and chemical resistance. The mixing ratio of mill base to hardener is generally 10:1. Compatibility with affordable PAC dispersions is good but must be tested on a case-by-case basis. view less |
