Abstract: Disclosed herein is a primer composition for metal materials, capable of forming a primer layer excellent in adhesion properties and film-forming properties on the surfaces of various metal materials such as common steel, stainless steel, aluminum, aluminum alloy, copper, and zinc plating to impart high bond strength and high bond durability when the metal materials are bonded with an epoxy-based adhesive. The primer composition is intended to be applied onto the surface of a metal material to be bonded with an epoxy-based adhesive and includes an epoxy resin containing both a bifunctional epoxy resin containing at least a bisphenol A-type epoxy resin and a multifunctional epoxy resin containing at least a phenol novolac-type epoxy resin, a curing agent composed of cyandiamide, a curing catalyst composed of imidazole, and an inorganic oxide filler composed of silica and titanium oxide.

Abstract: Disclosed herein is a primer composition capable of forming a primer layer excellent in adhesion properties and film-forming properties on the surfaces of various materials that may be bonded with an epoxy-based adhesive. The primer composition includes: an epoxy resin containing at least a bisphenol A-type epoxy resin and a phenol novolac-type epoxy resin; a curing agent being dicyandiamide; a curing catalyst being imidazole; and an inorganic oxide filler containing fumed silica, at least a surface of which is hydrophobic and which has a primary particle diameter of 7 to 40 nm and a specific surface area of 50 to 380 m2/g, in an amount of 0.5 to 3 parts by weight per 100 parts by weight of the total amount of the epoxy resins, wherein the primer composition includes no solvent.

Abstract: Disclosed herein is a primer composition capable of forming a primer layer excellent in adhesion properties and film-forming properties on the surfaces of various materials that may be bonded with an epoxy-based adhesive. The primer composition includes: an epoxy resin containing at least a bisphenol A-type epoxy resin and a phenol novolac-type epoxy resin; a curing agent being dicyandiamide; a curing catalyst being imidazole; and an inorganic oxide filler containing fumed silica, at least a surface of which is hydrophobic and which has a primary particle diameter of 7 to 40 nm and a specific surface area of 50 to 380 m2/g, in an amount of 0.5 to 3 parts by weight per 100 parts by weight of the total amount of the epoxy resins, wherein the primer composition includes no solvent.

Abstract: Disclosed herein is a primer composition for metal materials, capable of forming a primer layer excellent in adhesion properties and film-forming properties on the surfaces of various metal materials such as common steel, stainless steel, aluminum, aluminum alloy, copper, and zinc plating to impart high bond strength and high bond durability when the metal materials are bonded with an epoxy-based adhesive. The primer composition is intended to be applied onto the surface of a metal material to be bonded with an epoxy-based adhesive and includes an epoxy resin containing both a bifunctional epoxy resin containing at least a bisphenol A-type epoxy resin and a multifunctional epoxy resin containing at least a phenol novolac-type epoxy resin, a curing agent composed of cyandiamide, a curing catalyst composed of imidazole, and an inorganic oxide filler composed of silica and titanium oxide.