A liquid discharge apparatus includes an individual flow passage member; and a common flow passage member joined to the individual flow passage member in a first direction. The individual flow passage member has nozzle groups formed on a surface on a side opposite to the common flow passage member and connecting hole groups formed on a surface on a side of the common flow passage member; and the common flow passage member has manifold flow passages corresponding to the connecting hole groups respectively. Each of the nozzle groups includes nozzles aligned in a second direction orthogonal to the first direction; and each of the connecting hole groups includes connecting holes aligned in the second direction and connected to the nozzles respectively. Each of the manifold flow passages extends in the second direction and is connected to the nozzles via the connecting holes.

A liquid ejecting head includes: a nozzle; a pressure chamber; a supply flow channel which is located on one side in a first direction relative to the pressure chamber and through which a liquid is supplied to the pressure chamber; a discharge flow channel which is located on another side in the first direction relative to the pressure chamber and through which the liquid is discharged from the pressure chamber; a supply-side compliance substrate which absorbs a vibration of the liquid in the supply flow channel; and a discharge-side compliance substrate which absorbs a vibration of the liquid in the discharge flow channel. A length of the discharge-side compliance substrate in the first direction is shorter than a length of the supply-side compliance substrate in the first direction.

An actuator includes: a frame having a recess; an actuator substrate including a common chamber; a damper between the frame and the actuator substrate, the damper defining a part of a wall of the common chamber of the actuator substrate. The damper includes multiple layers laminated in a lamination direction, and the multiple layers is symmetrical in the lamination direction with respect to a center of the damper in the lamination direction.

A liquid ejecting head includes a pressure chamber substrate in which a pressure chamber space is formed, a flow path substrate having a first surface on which the pressure chamber substrate is installed and a second surface that is on the opposite side to the first surface, and in which a first space, a supply hole that enables communication between the first space and the pressure chamber space, and a communication hole that communicates with the pressure chamber space are formed, a nozzle plate that is installed on the second surface and in which a nozzle that communicates with the communication hole is formed, a second space that is installed on the first surface and that communicates with the first space of the flow path substrate, a housing unit in which an opening portion that communicates with the second space is formed, a compliance unit that is flexible and installed on the second surface and that seals the communication hole and the first space, and a beam-like portion that extends between inner wall surfaces of the second space in the housing unit.

A liquid-ejecting head includes a pressure-generating chamber communicating with a nozzle opening, and a piezoelectric element. The piezoelectric layer contains a perovskite complex oxide containing Bi, La, Fe, and Mn and is ferroelectric.

A liquid-ejecting head includes a pressure-generating chamber communicating with a nozzle opening, and a piezoelectric element. The piezoelectric layer contains a perovskite complex oxide containing Bi, La, Fe, and Mn and is ferroelectric.

A liquid ejection head has: a frame having a plurality of ejection ports for ejecting a liquid; a common liquid chamber; a plurality of individual liquid chambers through which the common liquid chamber communicates with each of the ejection ports; and a plurality of energy generating elements disposed in respective individual liquid chambers. A part of a wall of the frame that forms the common liquid chamber is formed of an elastic member capable of deforming elastically, so that a volume of the common liquid chamber can be modified.

A liquid jetting apparatus comprises a flow passage member which has a pressure chamber communicated with a nozzle and a liquid supply port communicated with the pressure chamber; a piezoelectric element with which the flow passage member is provided so that the piezoelectric element is overlapped with the pressure chamber; a protective member which is arranged on the flow passage member so that the piezoelectric element is covered therewith; and a supply member which is formed with a supply flow passage communicated with the liquid supply port of the flow passage member and which is adhered to extend over the flow passage member and the protective member; wherein a layer of a first adhesive to adhere the protective member and the supply member is thicker than a layer of a second adhesive to adhere the flow passage member and the supply member.

A liquid absorber including a liquid absorbent body configured to include a small piece aggregate including a plurality of small pieces having a fiber base material containing a fiber and a water absorbent resin, and a container that includes a wall portion defining a storage space accommodating the liquid absorbent body, and a protrusion portion provided to protrude from the wall portion toward the storage space, in which when a minimum separation distance between a tip end of the protrusion portion and a structure different from the protrusion portion is L1, and an average value of a distance between farthest ends of the small piece is L2, 0<L1/L2≤1.80 is satisfied.

A liquid ejecting head includes a pressure chamber that communicates with a nozzle which ejects liquid, a liquid chamber that communicates with the pressure chamber, a flexible compliance member that defines a portion of the liquid chamber, and a pressure adjusting mechanism that adjusts a supply pressure of liquid supplied to the liquid chamber. The pressure adjusting mechanism can adjust displacement of the compliance member.