Rheobyk 415 (formerly BYK 415)

Rheobyk 415 (formerly BYK 415) is a liquid rheology additive for solvent-borne automotive, industrial, and plastic coatings with excellent anti-sagging properties due to the quick structure recovery. It shows temperature-independent viscosity during flash-off and drying and is suitable for pneumatic and bell spray applications.

Rheobyk 415 works together with the binder and builds a three-dimensional network via hydrogen bonds and van der Waals forces. In addition to the dosage level and the polarity of the system, the degree of disentanglement of the higher molecular weight additive is key to the effectiveness.

The higher molecular weight and the more pronounced pseudoplastic flow behaviour are the reasons for the more temperature-stable viscosity behaviour of Rheobyk-415, even at higher drying temperatures.

Features and benefits include: improved anti-sagging properties in baking coatings and forced drying systems; temperature-stable viscosity behaviour; quick structural development and shear-stable viscosity profile; excellent compatibility, easy to use; no turbidity in the liquid clear coating; no haze and no significant UV yellowing.

Rheobyk 415 was developed specifically to improve the anti-sagging properties of coatings that are baked at higher temperatures or force dried. Applications are typical solvent-borne industrial and automotive coating systems that are applied at low layer thicknesses of 30 µm-70 µm dry film.