An ink jet head includes a nozzle plate substrate having a nozzle for ejecting ink toward a recording medium and an oil repellent film on a surface of the nozzle plate substrate, the surface facing the recording medium. The oil repellent film comprises a fluorine compound having a first end and a second end, the first end comprising a perfluoroalkyl group with 3 to 5 carbon atoms per each molecule of the fluorine compound, and a ratio of a density of CF2 groups in the oil repellent film with respect to a density of CF3 groups in the oil repellent film is between 1.5 and 4.0 as measured by X-ray photoelectron spectroscopic analysis.

There are provided a head chip and a method of manufacturing the same, a liquid jet head, and a liquid jet recording device each capable of suppressing a stray capacitance to improve the image quality. The head chip according to an embodiment of the present disclosure is a head chip having an actuator plate adapted to apply pressure to liquid to jet the liquid. The actuator plate includes an obverse surface and a reverse surface, a channel extending in a predetermined direction and having a first opening provided to the obverse surface and a second opening which is provided to the reverse surface and is shorter in length in the predetermined direction than the first opening, and an electrode having an obverse surface side part disposed on a sidewall of the channel on the first opening side, and a reverse surface side part which is disposed on the sidewall closer to the second opening than the obverse surface side part and is one of equal to and larger than the obverse surface side part in size in the predetermined direction.

There are provided a method of manufacturing a head chip capable of suppressing the occurrence of the failure in the process of forming the actuator plate to thereby increase the yield ratio, and a method of manufacturing a liquid jet head using the above method of manufacturing a head chip. The method of manufacturing a head chip according to an embodiment of the present disclosure is a method of manufacturing a head chip having an actuator plate adapted to apply pressure to liquid so as to jet the liquid. Forming the actuator plate includes forming a plurality of grooves on a surface of a piezoelectric substrate having one end and the other end so as to extend from the one end side toward the other end side, forming a conductive film on the surface of the piezoelectric substrate provided with the plurality of grooves, forming a laser processing area in the conductive film between the grooves adjacent to each other by performing laser processing from a start point on the one end side of the piezoelectric substrate to an end point on the other end side, and forming a surface removal area in at least a part including the start point and the end point out of the surface of the piezoelectric substrate by performing surface removal processing in a direction crossing the direction in which the laser processing is performed.

A liquid jet head chip capable of exerting an excellent ejection performance while having a compact configuration is provided. The liquid jet head chip is provided with an actuator plate, a common electrode, a common electrode pad for external connection, a cover plate, and a sealing plate. The actuator plate has an obverse surface, a reverse surface, and an ejection channel penetrating in a thickness direction and extending in a first direction perpendicular to the thickness direction. The common electrode is disposed on an inner surface of the ejection channel. The common electrode pad is disposed in an end part region in the first direction out of the reverse surface, and is coupled to the common electrode. The cover plate is disposed so as to be opposed to the obverse surface of the actuator plate, and has a liquid flow hole opposed to the ejection channel. The sealing plate is disposed so as to be opposed to a channel formation region other than the end part region out of the reverse surface of the actuator plate, and closes the ejection channel.

A liquid jet head chip capable of exerting a stable ejection performance is provided. The liquid jet head chip is provided with an actuator plate and an electrode. The actuator plate has an obverse surface, a reverse surface, and two or more ejection channels which penetrate the actuator plate in a thickness direction from the obverse surface toward the reverse surface, which are disposed so as to be adjacent to each other at intervals in a first direction perpendicular to the thickness direction, and which are disposed so as to extend in a second direction perpendicular to both of the thickness direction and the first direction. The electrode is disposed on an inner surface of the ejection channel, and includes a first electrode part covering the inner surface of the ejection channel continuously from the obverse surface toward the reverse surface, and a second electrode part covering the inner surface of the ejection channel continuously from the reverse surface toward the obverse surface, and overlapping at least a part of the first electrode part.

There are provided a head chip, a liquid jet head, and a liquid jet recording device capable of enhancing the reliability. An actuator plate adapted to apply pressure to the liquid, and a wiring board are provided. The actuator plate includes a first surface, and a second surface facing to an opposite side to the first surface, ejection channels and non-ejection channels which have an opening on at least one of the first surface and the second surface and are alternately arranged so as to be separated from each other, a common electrode disposed on a sidewall of the ejection channel, an individual electrode electrically separated from the common electrode and disposed on a sidewall of the non-ejection channel, a common electrode pad disposed on the first surface and adapted to electrically connect the common electrode and the wiring board to each other, and a bypass interconnection adapted to electrically connect the individual electrodes in the non-ejection channels adjacent to each other and failing to be exposed on the first surface.

A droplet deposition head having a fluid chamber connected to a droplet ejection nozzle and to a reservoir for the fluid, and a piezoelectric actuator element formed at least in part by a fluid chamber wall having an electrode thereon, which element is displaceable in response to a drive voltage to generate a pressure in the chamber to eject a droplet of fluid from the chamber through the nozzle wherein the electrode is provided with a passivation coating which comprises, at least in part, a laminate comprising an inorganic insulating layer nearest to or contacting the electrode and an organic insulating layer overlying the inorganic insulating layer wherein defects in the insulating layers tend to be misaligned at the interface there between and wherein the inorganic insulating layer has thickness less than or equal to 500 nm and the organic insulating layer has a thickness less than 3 m.

There is provided a liquid jet head and a liquid jet recording device capable of increasing available ink types. The liquid jet head according to an embodiment of the present disclosure is provided with an actuator plate having a plurality of ejection grooves, a nozzle plate having nozzle holes communicated with the ejection grooves, and a nozzle guard having a rib adapted to support the nozzle plate, and a communication hole adapted to communicate each of the first nozzle holes and an outside with each other. The rib has contact with the nozzle plate at a position which fails to be opposed to an opening on the nozzle plate side of each of the ejection grooves.

According to an embodiment, an ink jet head (liquid ejecting head) includes an actuator plate and a cover plate (see FIG. 8). As illustrated in FIG. 1, channel grooves for a discharge channel (ejection channel) and a non-discharge channel (non-ejection channel) in a Z-direction are formed on a front surface of the actuator plate, so as to be alternately arranged in an X-direction, by cutting with a dicing blade or the like. The discharge channel and the non-discharge channel are formed to have a groove width W of smaller than 70 m, in order to correspond to high density of nozzles. In the embodiment, the discharge channel and the non-discharge channel are formed to have a groove width of 55 m, 50 m, or 40 m, for example.

According to an embodiment, an ink jet head includes a pair of actuator plates, a return plate, and a flow passage plate. The pair of actuator plates are disposed to face each other in a Y-direction. In the actuator plate, a plurality of channels which extend in a Z-direction are arranged at a distance in an X-direction. The return plate is disposed on an opening end side of the channels in the pair of actuator plates. A circulation passage which communicates with the channels is formed in the return plate. The flow passage plate is disposed between the pair of actuator plates. An inlet flow passage into which an ink flows and an outlet flow passage which communicates with the circulation passage are arranged in the Z-direction.