A liquid ejection head includes an ejection-port defining member and a substrate having at least three liquid supply openings arranged in an array direction. The substrate has at least one groove in a region between ends of the liquid supply openings and an edge of the substrate. The groove extends from and communicates with the end of at least one of two outermost liquid supply openings of the liquid supply openings in the array direction. The groove extends at least to a position where the groove is superposed on the liquid supply opening next to the liquid supply opening communicating with the groove in an extending direction in which the liquid supply openings extend.

A liquid discharge head includes a base plate, a cavity plate located on the base plate and including a cavity, and a piezoelectric actuator substrate located on the cavity plate. The cavity plate includes: a first groove located inside a contact region with the piezoelectric actuator substrate and configured to release an adhesive for bonding the cavity plate and the piezoelectric actuator substrate; and a second groove located in a manner to surround the contact region with the piezoelectric actuator substrate and configured to release the adhesive. The base plate includes a third groove configured to open the first groove to the atmosphere. The third groove is configured to communicate between the first groove and the outside through a first hole communicating with the first groove and a second hole located outside the contact region of the cavity plate and the piezoelectric actuator substrate.

According to one embodiment, a liquid ejection head includes an actuator with a plurality of pressure chambers and dummy chambers. The pressure chambers are each part of a groove that is disposed between an adjacent pair of sidewalls. Each pressure chamber is in fluid communication with a nozzle for ejecting a liquid. The dummy chambers are each between an adjacent pair of pressure chambers. A common chamber is fluidly connected to an end of each of the pressure chambers. A throttle portion is at the end portion of each pressure chamber. Each throttle portion blocks a part of a liquid flow path from the first common chamber to the pressure chamber. The first throttle portion is formed of a resin material.

A printing apparatus and a method of providing printing apparatus are provided. A printing apparatus according to at least one embodiment of the present disclosure includes a base panel or head base, at least one or more head packs installed on the head base, a head pack holder installed on each of the head packs and configured to handle and fix the head pack, and a fastening structure configured to mount the head pack holder to the head packs.

The head has a passage member having a nozzle and a pressurizing chamber which is communicated with the nozzle and is positioned on the side opposite to the side where the nozzle is opened, a piezoelectric actuator substrate which is superimposed on the passage member so as to cover the pressurizing chamber, and a flexible printed circuit which faces the piezoelectric actuator substrate from the opposite side to the passage member. The piezoelectric actuator substrate has a piezoelectric body which is exposed on the flexible printed circuit side. The piezoelectric body has a via hole opened toward the flexible printed circuit and has a projection portion at the edge part of the via hole which projects to the flexible printed circuit side.

A liquid discharge head includes an actuator base, a case member, and a nozzle plate. The actuator base includes a plurality of grooves space from each other in a first direction. Each of the grooves extends in a second direction. The actuator base is formed of a piezoelectric ceramic material. The case member includes a frame portion spaced from the actuator base in the second direction. The frame portion has an end surface in the third direction that is level with an end surface of the actuator base in the third direction. The frame portion is formed of a ceramic material having aluminum titanate as a main component. The nozzle plate is contacting the end surface of the frame portion and the end surface of the actuator base.

An inkjet head manufacturing method for an inkjet head that includes a head chip including: a nozzle ejecting ink; and a flow path substrate including an ink flow path which communicates with the nozzle and through which the ink flows, the method including: composite substrate manufacturing that is manufacturing a composite substrate including a plurality of regions which forms flow path substrates by being split; first protective film forming that is forming a first protective film on a surface of the composite substrate and an inner wall surface of the ink flow path; splitting that is splitting the composite substrate into the flow path substrates; and second protective film forming that is forming a second protective film on at least an exposed face in a split face of the flow path substrate generated in the splitting, the exposed face being exposed in a surface of the head chip.

A recording method of the present disclosure, which is a recording method of performing recording on a recording medium by using a recording device including an ink jet head, includes ejecting a composition for ink jet from the ink jet head, in which the composition for ink jet contains a metal pigment, the metal pigment is formed of a plurality of scaly metal particles, the ink jet head includes a circulation flow path for circulating the composition for ink jet, and an average thickness of the metal particles determined by atomic force microscopy is 19 nm or less.

A fluid ejection head may include an integrated chamber-orifice layer forming an ejection chamber and an ejection orifice, a fluid actuator to eject fluid within the chamber through the ejection orifice, an orifice shield and an adhesive layer bonding the orifice shield to the integrated chamber-orifice layer.

The electrohydrodynamic print head comprises a plurality of nozzles. Each nozzle has a central nozzle duct laterally surrounded by a nozzle wall. The top end of the nozzle duct communicates with an ink feed duct. An annular trench laterally surrounds the nozzle. An extraction electrode is located around the axis of the nozzle at a level below it, and a shaping electrode located laterally outside the nozzle duct. The shaping electrode is arranged within a ring having a horizontal width of less than the vertical distance between said shaping electrode and the extraction electrode or it is located above the trench. Both these measures allow to operate the device with high voltages with reduced risk of electrical breakdown.