When inorganic pigments are modified with the silancs according to this invention, the properties imparted to them are such that they can advantageously be used as fillers for thermosetting resins such as polyurethanes, epoxy polymers, melamine polymers, phenolic polymers, ureaformaldehyde polymers, unsaturated polyesters, as well as other polymers and elastomers including polyethylenes, polyprop