Method for producing protective-layer-covered gas separation membrane, protective-layer-covered gas separation membrane, gas separation membrane module, and gas separation apparatus

A method for producing a protective-layer-covered gas separation membrane, the method comprising:

• forming a gas separation membrane having a resin layer containing a compound having a siloxane bond by surface oxidation treatment of a resin layer precursor containing a siloxane bond with an input power of 23 W or more;
• and
• providing a protective layer on the resin layer before winding,
• wherein the gas separation membrane satisfies one of conditions 1, 3, and 4:
• condition 1:
• the resin layer satisfies inequalities 1 and 2:
• 0.9≥A/B≥0.55 inequality 1:
• B≥1.7 inequality 2:
• wherein A represents an O/Si ratio that is a ratio of the number of oxygen atoms to the number of silicon atoms contained in the resin layer at a depth of 10 nm from a surface of the resin layer, and B represents an O/Si ratio that is a ratio of the number of oxygen atoms to the number of silicon atoms in the surface of the resin layer;
• condition 3:
• a minimum percentage Si0 of Si2+ and Si3+ peaks relative to all Si peaks in ESCA depth profiling of the resin layer is 1% to 40%;
• and
• condition 4:
• a positron lifetime τ3 of a third component formed by implantation of a positron with an energy of 1 keV into the surface of the resin layer is 3.40 to 4.20 ns.