COMPOSITION FOR SURFACE TREATMENT

摘要

An aqueous composition for the treatment of surfaces such as metals particularly aluminium, comprises a tetraalkyl silicate or a monomeric or oligomeric hydrolysis product thereof, and an inorganic passenger powder below 100 nm diameter such as fumed silica, both in dispersion in a fluid aqueous medium. The composition can be applied as a conversion coating to improve the adhesion of subsequently applied paint, lacquer or adhesive. Non-aqueous intermediate products comprising the silicate component and passenger powder can be diluted with water to make the coating composition.