Patent ID: 8772391

Claim:
A composite structure comprising an electrically conductive surfacing film formed on a composite substrate, wherein the surfacing film is capable of providing lightning strike protection and electromagnetic interference shielding, has an electrical resistivity of less than 500 mΩ/sq, a film weight in the range of 0.01-0.15 psf (pounds per square foot), and is formed from a curable thermosetting composition comprising: a. at least one multifunctional epoxy resin; b. at least one curing agent selected from the group consisting of: aromatic primary amines, bisureas, boron trifluoride complexes, and dicyandiamide; c. at least one toughening agent having a functional group selected from epoxy groups, carboxylic acid groups, amino groups and hydroxyl groups capable of reacting with other components of the composition; d. non-conductive fillers; e. conductive additives in an amount greater than about 35 wt. %, based on the total weight of the composition.