Abstract: An inkjet recording device including: inkjet head having a pressure chamber; a first pressure source to adjust ink energy per unit volume to generate “energy per unit volume” P1(Pa) relative to static ink at an atmospheric pressure at a nozzle opening height; a second pressure source to adjust ink energy per unit volume to generate “energy per unit volume” P2(Pa) relative to static ink; and a hardware processor. The first pressure source, pressure chamber, and second pressure source are connected in this order by a flow path. Assuming that a pressure loss occurring from the first pressure source to the nozzle due to circulation flow rate is ?Pa, a proportionality constant of a differential pressure (P1?P2) and ?Pa is “a”, and an appropriate pressure in vicinity of the nozzle opening is Pn, the hardware processor controls pressure to establish P2={Pn?(1?a)P1}/a.

Abstract: An image forming apparatus includes: an inkjet head; an ink reservoir that stores ink circulating between the inkjet head and the ink reservoir; a pressure generating unit that communicates with the inkjet head and generates a first pressure such that an internal pressure of the ink reservoir becomes the first pressure; and a first fluid resistor that gives resistance to a fluid flowing through a fluid communication path between the ink reservoir and the pressure generating unit such that the internal pressure of the ink reservoir becomes a second pressure.

Abstract: An inkjet recording device including: inkjet head having a pressure chamber; a first pressure source to adjust ink energy per unit volume to generate “energy per unit volume” P1(Pa) relative to static ink at an atmospheric pressure at a nozzle opening height; a second pressure source to adjust ink energy per unit volume to generate “energy per unit volume” P2(Pa) relative to static ink; and a hardware processor. The first pressure source, pressure chamber, and second pressure source are connected in this order by a flow path. Assuming that a pressure loss occurring from the first pressure source to the nozzle due to circulation flow rate is ?Pa, a proportionality constant of a differential pressure (P1?P2) and ?Pa is “a”, and an appropriate pressure in vicinity of the nozzle opening is Pn, the hardware processor controls pressure to establish P2={Pn?(1?a)P1}/a.

Abstract: The present invention may provide an ink jet head and an ink jet recording apparatus capable of satisfactorily removing remaining air bubbles from a pressure chamber. The present invention may include: a common ink chamber that stores ink; at least one pressure chamber that communicates with the common ink chamber and causes a volume fluctuation using pressure generation means; a nozzle that communicates with the pressure chamber; a nozzle-part discharge path that communicates with the pressure chamber near the nozzle inside the pressure chamber and discharges ink out of the pressure chamber; and at least one discharge path that communicates with the pressure chamber at a position apart from the nozzle inside the pressure chamber and discharges ink out of the pressure chamber.

Abstract: The present invention may provide an ink jet head and an ink jet recording apparatus capable of satisfactorily removing remaining air bubbles from a pressure chamber. The present invention may include: a common ink chamber that stores ink; at least one pressure chamber that communicates with the common ink chamber and causes a volume fluctuation using pressure generation means; a nozzle that communicates with the pressure chamber; a nozzle-part discharge path that communicates with the pressure chamber near the nozzle inside the pressure chamber and discharges ink out of the pressure chamber; and at least one discharge path that communicates with the pressure chamber at a position apart from the nozzle inside the pressure chamber and discharges ink out of the pressure chamber.

Abstract: To provide a novel material exhibiting excellent light-emitting characteristics using a heavy metal element having relatively abundant reserve.

Abstract: The present invention provides a metal complex that has excellent durability, and a device and the like having excellent durability that uses such a metal complex. Specifically, the present invention provides a metal complex comprising (a) a polydentate ligand having denticity of five or more that includes a heteroaromatic ring which contains two or more atoms selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom, and (b) an ion of a metal selected from the group consisting of cerium, praseodymium, ytterbium, and lutetium; a composition comprising the metal complex and a charge transport material; an organic thin film obtained by using the metal complex or composition; and a device obtained by using the metal complex, composition, or organic thin film.

Abstract: An organic electroluminescent device in which an organic layer containing a metal coordination compound represented by the following formula (1) is sandwiched between the pair of electrodes composed of an anode and a cathode, MLaXb??(1) wherein M is an ion of a metal of Group 11 of the Periodic Table, L is a ligand represented by the formula (2) shown below, X is an anion, and a and b are defined in the specification, wherein A is a divalent group formed by removing two hydrogen atoms from the formula (3) or (4) shown below, and D1, k1, m1, A, D1, Q1, and Q2 are defined in the specification, wherein X1, X2, X3, X4, X5, R1, R5, R6, and R9 are defined in the specification.

Abstract: A metal complex containing a nitrogen-containing aromatic ring ligand which has a dendritic molecular chain, and a copper(I) ion or a silver(I) ion. For example, the metal complex which is represented by compositional formula (8): (wherein M+ is a copper(I) ion or a silver(I) ion, L is a ligand, and X is a counter ion; p is a positive number, and q and r are each independently numerical numbers of 0 or more; R represents a hydrogen atom, a halogen atom, a cyano group, a nitro group, a carboxyl group, an amino group, an acylamino group, a silyl group, a hydroxyl group, an acyl group, a hydrocarbyl group, a hydrocarbyloxy group, a hydrocarbylthio group, or a heterocyclic group, wherein the amino group, the silyl group, the hydrocarbyl group, the hydrocarbyloxy group and the hydrocarbylthio group optionally have a substituent) has excellent heat resistance.