Byk -067 A Polysiloxane BYK Chemie Defoamer / Antifoaming agent >> Silicone Coatings >> Solventborne Coatings >> Solvent-Free/ High-Solids Coatings >> UV / Radiation Curing Inks INKS Propylene glycol Byk® -067 A is a non-aqueous emulsion of a foam destroying polysiloxane. BYK®-067 A is the solvent-free and odor-free version of BYK®-066 N. It is especially suitable for defoaming of aromatic-free paints and high solid systems. Non-aqueous emulsion of a foam destroying polysiloxane. Used in paints and inks.