forming a liquid flow duct pattern, from a dissolvable resin, in a portion of a substrate carrying a liquid ejecting energy generating device, said portion later becoming a liquid flow duct;

forming a coated resin layer on said dissolvable resin on which said liquid flow duct pattern has been formed;

forming a liquid ejecting opening in a portion of said coating resin layer overlying said liquid ejecting energy generating device; and

dissolving said dissolvable resin; wherein

said coating resin layer is formed of an oxetane resin composition that contains, as necessary components, an oxetane compound having at least one oxetanyl group in a molecule, and a cationic photopolymerization initiator, and

in said coated resin layer forming step, (a) a solution of feedstock components of said oxetane resin composition and said cationic photopolymerization initiator dissolved in a solvent which does not dissolve said dissolvable resin, is used and (b) a cured product of said feedstock components of said solution is generated, said dissolvable resin being dissolved to exit said liquid ejecting opening to form said liquid flow duct communicating with said liquid ejecting opening.