Aminosilane modified zinc-rich coating compositions

Claim 1

A composition for protecting ferrous metals from corrosion comprising particulate zinc, an unhydrolyzed or a partially hydrolyzed organic silicate hydrolyzed up to about 40% and a hardening amount of an aminoorganosilicon acylamino compound having the formula: ##STR18## wherein: X is an alkoxy radical having 1 to 6 carbon atoms; R is a alkylene radical having 1 to 4 carbon atoms; R 1 is hydrogen or an alkyl radical having 1 to 4 carbon atoms; R 2 is an alkylene radical having 2 to 4 carbon atoms; R 3 is a monovalent radical selected from the group consisting of hydrogen alkyl having 1 to 20 carbon atoms or phenyl; R 4 is a monovalent radical selected from the group consisting of alkyl having 1 to 20 carbon atoms, phenyl or silyl having the formula: ##STR19## wherein X, R and R 1 are as defined above; Q is a monovalent radical selected from the group consisting of hydrogen, alkyl having 1 to 4 carbon atoms, phenyl or an ester radical having the formula --COOR 5 wherein R 5 is alkyl having 1 to 4 carbon atoms; a is an integer having values of 0 to 2 and t and x are each integers having a value of 0 to 4, with the proviso that when x is at least 1, R 4 can also be hydrogen.