Corrosion-protective primers - for iron and steel, contg anodic metals, graphite and/ r carbon black

摘要

The primer consists of an organic and/or inorganic binder contg. anodic metal pigments (e.g. zinc) and solvents or diluents with pigment level pref. corresponding to the critical pigment volume conc. with addition of carbon pigments such as graphite and/or carbon black. Pref 20 - 50 vol. % of the metal pigment is replaced by the carbon pigment, which pref. consists of coarse graphite particles of over 40 microns dia. together with fine carbon black particles to fill the spaces left between the larger particles. Electrical conductivity of the film, which is of decisive importance in cathodic corrosion protection, is improved by power of ten.