10/23/2012

www.gupta-verlag.de/polyurethanes

New series of hydroxyl-functional polyurethane dispersons

[image_0]These anionic products are intended for two-component (2K) coating systems, primarily for use in an industrial environment such as OEM, where heat-curing or stoving conditions can be employed. They must be crosslinked with water-dispersible polyisocyanates, aqueous blocked isocyanates or melamine-formaldehyde (MF) resins typically used in the water-based coatings industry. When formulated correctly, protective coatings with high gloss and clarity can be obtained on a variety of substrates including plastics, primed metals, concrete and masonry. In keeping with the latest health and safety requirements, these new Witcobond products do not contain surfactants, N-methylpyrrolidone (NMP) or triethylamine (TEA). Three initial grades are offered, each at 35 % by weight solids and with a hydroxyl (OH) content of 2.5 % (on solids). As indicated below, they have different chemical backbones, which allows the compounder flexibility to meet a range of technical parameters and specifications: Witcobond 428-85 is based on aliphatic diisocyanate/polyether polyol and is cosolvent-free. Witcobond 434-55 is based on aliphatic diisocyanate/polyester polyol and is cosolvent-free.Witcobond 434-65 is based on aliphatic diisocyanate/polycarbonate polyol and contains 4 % glycol ether. Samples and further technical information such as guide formulations and application test results are available for customers on request. Witcobond polyurethane dispersion grades are supplied globally from the Baxenden manufacturing site in Droitwich, UK, and from the Chemtura manufacturing site in Perth Amboy, New Jersey, USA.

www.gupta-verlag.de/polyurethanes