Method for producing fine structured member, method for producing fine hollow structured member and method for producing liquid discharge head

A method for producing a fine hollow structured member on a substrate comprising:

• a step of forming a positive-working photosensitive material on a substrate;
• a step of heating the layer of said positive-working photosensitive material thereby crosslinking said positive-working photosensitive material layer;
• a step of executing an irradiation with an ionizing radiation of a first wavelength region capable of decomposing said crosslinked positive-working photosensitive material layer on a predetermined area of said crosslinked positive-working photosensitive material layer;
• and
• a step of removing, by a development, the area irradiated by the ionizing radiation of said crosslinked positive-working photosensitive material layer from the substrate, thereby obtaining a mold pattern formed by a non-irradiated area by the ionizing radiation of said crosslinked positive-working photosensitive material layer;
• a step of forming a covering resin layer, formed by a negative-working photosensitive material sensitive to a second wavelength region, in a position covering at least a part of the mold pattern on said substrate;
• a step of irradiating said covering resin layer with an ionizing radiation of the second wavelength region thereby hardening said covering resin layer;
• and
• a step of removing, by dissolution, the mold pattern covered by said hardened covering resin layer from the substrate thereby obtaining a hollow structure corresponding to said mold pattern;
• wherein said positive-working photosensitive material includes a ternary copolymer containing methyl methacrylate as a main component, methacrylic acid as a thermally crosslinkable factor and a factor for expanding a sensitivity region for said ionizing radiation;
• and
• said first wavelength region and said second wavelength region do not overlap mutually.