Steel pipe for vehicle piping
AssigneeSanoh Kogyo Kabushiki Kaisha
InventorsYoshihisa Tamura, Naoki Kawai
Life of this patent
Estimating the term…
Abstract
A steel pipe has a multi-layer coating including: a plating film formed on the surface of the steel pipe; a chemical conversion coating covering the plating film; a primer coating covering the chemical conversion coating and formed from a curable epoxy resin composition composed mainly of an epoxy compound and having an amide or imide bond introduced; and a polyamide resin coating covering the primer coating. The multi-layer coating can significantly enhance the adhesion force of the polyamide coating compared to the conventional pipe.
Claims11
A coated pipe for automotive piping, comprising a steel pipe coated with a multi-layer coating, wherein the multi-layer coating comprises:
- a plating film formed on the surface of the steel pipe;
- a chemical conversion coating covering the plating film;
- a primer coating covering the chemical conversion coating and a polyamide resin coating covering the primer coating;
- wherein the primer coating is made by baking a curable composition composed mainly of a curable epoxy resin but also comprising a polyamide imide to form the primer coating as a baked composition that provides for enhanced adhesion of the primer coating to the polyamide resin coating as compared with the baked composition if made by baking the curable composition except that the curable composition does not comprise any polyamide imide.
A coated pipe for use in fuel piping wherein it can come into contact with gasohol, the coated pipe comprising a steel pipe coated with a multi-layer coating, wherein the multi-layer coating comprises:
- (a) a plating film formed on a surface of the steel pipe,
- (b) a chemical conversion coating covering the plating film;
- (c) a primer coating covering the chemical conversion coating and a polyamide resin coating covering the primer coating;
- wherein the primer coating is formed by baking a curable composition composed mainly of a curable epoxy resin but also comprising a polyamide imide to form the primer coating as a baked composition that provides for enhanced adhesion of the primer coating to the polyamide resin coating as compared with the baked composition if made by baking the curable composition except that the curable composition does not comprise any polyamide imide.
Dependencies are inferred from the claim text.