A dispersion of a polytetrafluoroethylene resin having a particle size between about 0.05 and 0.5 microns, a suspending agent and a viscosity less than 15 centipoise. The dispersion has long shelf life, a reduced tendency to fibrillate and is comparatively stable when acted upon by shear forces and elevated temperatures. The dispersion is well adapted to be sprayed onto surfaces to form a dried film upon which insects can not climb, alight or affix nests or webs. The dispersion can be sprayed without fibrillation dispersion and the dried coatings are adherent, may be washed and remain effective over long periods of time.
