A method for manufacturing a liquid ejection head including the steps of preparing a substrate including, on a surface of the substrate, a layer having a plurality of openings in which opening portions of supply portions are located and which are arrayed in an array direction and another opening which is different from the plurality of openings and is located beyond the array end portion in the array direction, and attaching a dry film for forming flow passages to the substrate and the layer.

A method of forming a through-substrate having a first surface and a second surface opposite to the first surface, the method causing the first surface to communicate with the second surface through the substrate, the method including: a first step that forms a first trench from the first surface side of the substrate using dry etching, the first trench having side surfaces on which protective film is formed; and a second step that forms a second trench from the second surface side using dry etching, the second trench communicating with the first trench having the side surfaces on which the protective film is formed.

A method for manufacturing a liquid ejection head includes the steps of: preparing a substrate including an energy-generating element disposed on a first surface of the substrate and a supply path for liquid; disposing a dry film on the first surface of the substrate in such a manner that the dry film partially enters the supply path; etching the dry film from a side of the dry film facing the first surface of the substrate so that the dry film has an etched surface substantially in parallel with the first surface and covers the supply path; forming a resin layer to be a flow path member on the dry film covering the supply path; and removing the dry film covering the supply path.

An ejection material ejecting device includes: an ejection unit including an ejection opening configured to eject an ejection material; an electric substrate configured to control ejection of the ejection material; a first flexible cable connected to the ejection unit; a second flexible cable connected to the electric substrate; and a joint at which the first flexible cable and the second flexible cable are joined by an anisotropic conductive film, wherein the joint is covered with a sealant resistant to the ejection material.

A hydrophilic coating material including an alginate compound having a bond with a silane compound is used. The material is produced by reacting a water-soluble alginate compound and a silane compound and then by adding a divalent metal ion to an alginic acid-derived carboxyl group in the reaction product.

A microfluidic ejection chip includes a silicon substrate having a fluid passageway. The fluid passageway is defined by a silicon sidewall of the silicon substrate that is covered by a permanent passivation layer to protect the silicon sidewall from exposure to an acidic fluid. The permanent passivation layer is retained on the silicon sidewall at a conclusion of etching of the silicon substrate to form the fluid passageway.

An ink-jet recording head includes a plurality of recording element substrates each having an ejection pressure generating element configured to generate pressure for ejecting ink from an ink discharge port. The plurality of recording element substrates each include a first surface on which the corresponding ejection pressure generating element is disposed and a second surface, serving as an end surface intersecting with the first surface, being at least partially formed by etching.

An inkjet printhead includes a head body in which a first fine channel that is connected to an ink inlet and thus guides an inflow of ink, a second fine channel that is disposed below the first fine channel, communicated with the first fine channel through a connection via hole, and guides an outflow of the ink by being connected to an ink outlet, and a nozzle that is opened downward from the second fine channel are defined, and a micro heater that is disposed closer to the connection via hole in an upper portion of the first fine channel than to an end of the first fine channel where the first fine channel is connected to the ink inlet or an end of the second fine channel where the second fine channel is connected to the ink outlet.

A liquid discharge head includes a plurality of recording element substrates each having an energy generating element configured to generate energy for discharging liquid from a discharge port, and a sealing member with which a surround of each of the plurality of recording element substrates is filled. Each of the plurality of recording element substrates includes a recessed portion formed on an end surface facing a neighboring recording element substrate, and in the recessed portion, a gap between neighboring recording element substrates is wider than a gap between element surfaces on which the energy generating element is provided.

Aspects are directed to techniques for fabricating a microfluidic device on a substrate. In a particular example, a method of manufacturing a microfluidic device includes growing a thermal oxide layer on a substrate and depositing a dielectric layer, including doped a dielectric film, over the thermal oxide layer. Next, an aperture defined by a dielectric wall which forms part of the dielectric layer is formed in the dielectric layer by selectively removing the dielectric film. Finally, the aperture is sealed with a sealing film to prevent the dielectric film from being exposed to a fluid contained in the aperture. The sealing film may be of an electrically insulating material resistive to corrosive attributes of the fluid contained in the aperture.