Provided is a method for manufacturing a liquid ejection head including an ejection orifice for ejecting a liquid, a substrate and a flow path forming member that is joined to the substrate to form a liquid flow path communicating with the ejection orifice, the method including: (1) forming a resin layer having a flow path mold pattern, on the substrate; (2) adding a hydrophilizing material represented by Chemical Formula 1 to an entire surface layer of the resin layer; (3) forming a covering resin layer serving as the flow path forming member, on the resin layer and forming a compatible layer containing the resin layer, the covering resin layer and the hydrophilizing material, at an interface between the resin layer and the covering resin layer; (4) forming the ejection orifice by exposing the covering resin layer; and (5) forming a flow path by removing the resin layer.

A liquid discharge head is provided which has a substrate, a flow channel forming member provided on a substrate surface of the substrate and forming a flow channel of a liquid, and a discharge port forming member provided on the flow channel forming member and having a discharge port through which a liquid is discharged, wherein the discharge port forming member and the flow channel forming member are formed of materials different from each other, a thickness of the flow channel forming member is greater than a thickness of the discharge port forming member in a direction perpendicular to the substrate surface, the discharge port forming member is a cured product of a photosensitive resin composition, and the flow channel forming member contains at least one resin selected from the group consisting of a polyether amide resin, a polyether imide resin and a polyether amide-imide resin.

A method of manufacturing a liquid discharge head substrate is provided. The method includes forming a first substrate that includes a semiconductor element and a first wiring structure; forming a second substrate that includes a liquid discharge element and a second wiring structure; and bonding the first wiring structure and the second wiring structure such that the semiconductor element and the liquid discharge element are electrically connected to each other after the forming the first substrate and the second substrate.

Provided is a method of manufacturing a liquid ejection head, which is capable of patterning a dry film while suppressing deformation of the dry film caused by a pressure. The method of manufacturing a liquid ejection head includes: preparing a substrate including an ejection orifice member on a first surface; forming, on an ejection orifice surface of the ejection orifice member, a protection film having communicating holes for allowing ejection orifices to communicate to outside; closing an opening of a supply port on a second surface on a side opposite to the first surface of the substrate with a dry film; and patterning the dry film by irradiating the dry film with light under a state in which the protection film is formed on the ejection orifice surface.

A method of manufacturing a liquid ejection head includes forming a resist film on a first surface of a light-transmitting support having the first surface and a second surface being a back surface of the first surface; bonding a back side of the surface of the resist film to the support side on a substrate having a through hole so as to block the through hole; exposing the resist film with light transmitted from the second surface to the first surface of the support and forming a portion which is removable with a dissolving liquid and a portion which remains against the dissolving liquid on the resist film; immersing the substrate and the exposed resist film in the dissolving liquid, allowing the dissolving liquid to enter the through hole, and removing the removable portion; and peeling the support from the resist film from which the removable portion has been removed.

An improved photoimageable dry film formulation, a fluidic ejection head containing a thick film layer derived from the improved photoimageable dry film formulation, and a method for making a fluidic ejection head. The improved photoimageable dry film formulation includes a multifunctional epoxy compound, a photoinitiator capable of generating a cation, a non-photoreactive solvent, and from about 0.5 to about 5% by weight a silane oligomer adhesion enhancer based on a total weight of the photoimageable dry film formulation before drying.

A method of manufacturing a semiconductor substrate includes: forming a barrier metal layer on a semiconductor substrate; forming a resist mask on the barrier metal layer; performing dry etching on a portion of the barrier metal layer, which is exposed from an opening portion of the resist mask, so that the dry etching is prevented from reaching a top surface of a layer immediately under the barrier metal layer; performing wet etching on a portion of the barrier metal layer exposed by the dry etching so that the wet etching reaches the top surface of the layer immediately under the barrier metal layer and a portion of the barrier metal layer remains; and stripping the resist mask.

A hydrophilic coating material including an alginic acid compound and a resin, in which the alginic acid compound is granulated and dispersed in the resin. In a coating film using the material, it is preferred that the granulated alginic acid compound is exposed on the surface. Such a hydrophilic coating film is suitable as a hydrophilization treatment film of a nozzle face surface of an inkjet recording head.

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 substrate includes a first substrate which has a first substrate through hole, and a second substrate which has a second substrate through hole and directly or indirectly overlaps the first substrate, the first substrate through hole and the second substrate through hole directly or indirectly communicate with each other to form a liquid supply path and a width D1 of an opening portion of the first substrate through hole on a surface of the first substrate closer to the second substrate, a width D2 of an opening portion of the second substrate through hole on a surface of the second substrate closer to the first substrate, a width D3 of an opening portion of the second substrate through hole on a surface of the second substrate farther from the first substrate have a relationship of D1<D2 and D3<D2.