Electrically conductive coating composition of a glycidyl acrylic polymer and a reactive polysiloxane

Claim 1

A coating composition comprising about 10-80% by weight of a film forming binder and 20-90% by weight of a liquid carrier, wherein the binder consists essentially of a blend of about a. 20-90% by weight, based on the weight of the binder, of an acrylic polymer consisting essentially of about 10-50% by weight, based on the weight of the acrylic polymer, of polymerized glycidyl methacrylate or glycidyl acrylate and 50-90% by weight of polymerized ethylenically unsaturated monomers selected from the group consisting of an alkyl methacrylate having 1-12 carbon atoms, an alkyl acrylate having 1-12 carbon atoms, styrene, alkyl substituted styrenes and mixtures thereof, wherein the acrylic polymer has a weight average molecular weight of about 10,000-100,000, and b. 10-80% by weight, based on the weight of the binder, of a crosslinkable polysiloxane having the following units: ##STR2## where R and R 1 are individually selected from the group consisting of alkyl group having 1-6 carbon atoms, hydroxyl groups and phenyl group and contains a sufficient number of hydroxyl groups to provide a silanol content of about 0.5-7% by weight; wherein the coating composition contains electrically conductive pigments in a pigment to binder weight ratio of about 50/100 to 300/100 and a dry film of the coating composition 25 microns thick has an electrical resistance of about 1-50 ohms.