GB482458A - Improvements in coating compound and method for production thereof - Google Patents

Abstract

A coating-composition is produced by blending a partially condensed thermo-setting phenol-formaldehyde resin with a metal-adherent resin in a common solvent containing at least 5 per cent (reckoned on the phenolformaldehyde resin) of a high-boiling solvent. Specified metal-adherent resins are fatty-acid modified or blown castor-oil modified polyhydric alcohol-polybasic acid resins, e.g. glycerol-phthalic anhydride resin modified by non-drying or drying oil fatty acids such as linseed and wood-oil acids; natural gum fossil resins, e.g. Kauri; and the gasoline-insoluble portion of oxidized abietic acid known under the Registered Trade Mark "Vinsol." The high-boiling solvent may be a phenol, e.g. cresol or xylenol, cyclohexanone, methyl cyclohexanone, cyclohexanol, benzyl alcohol. The composition may be used as a primer; as a coating on concrete and metals such as galvanized iron or aluminium; for the coating or impregnation of rubber and fibrous materials, e.g. wall, gypsum, or open-pore insulating boards, to protect them against termites or fungi; and may be mixed with white lead. In an example: m- or other cresol is condensed with formaldehyde, or a polymer thereof, e.g. paraformaldehyde, in the presence of caustic soda until a sample cooled to room temperature is a stiff gel, the resin is separated from the water of condensation, and there is added 10 per cent of m-cresol and 20 per cent of denatured ethyl alcohol followed by 10 per cent of fatty-acid modified polyhydric alcohol-polybasic acid resin, as solid or in solution, (all percentages being reckoned on the phenol-formaldehyde resin).