An inkjet printing apparatus includes a stage on which a target substrate is mounted, and an inkjet head positioned above the stage, wherein the inkjet head includes an ejection part including a plurality of nozzles that spray ink containing a plurality of particles, a filter part disposed above the ejection part, and selectively passing the plurality of particles, and an electric field generating electrode that is disposed in the filter part and generates an electric field in the filter part.

A cosmetic handy ink-jet printer including an ink-jet head for ejecting an ink containing an inorganic pigment, an ink circulation device for circulating the ink, and a body deelectrification device for removing static electricity from a body of the printer. The ink circulation device includes an ink receptacle in which the ink is accommodated, and an ink circulation path through which the ink is circulated. The body deelectrification device is a capacitor or a grounded circuit.

A method of applying a cap to a printhead may comprise selectively applying an immiscible fluid to a surface of a printhead in which the immiscible fluid caps a number of nozzles on a number of nozzles defined within the printhead. A printhead may comprise a layer of immiscible fluid in which the immiscible fluid is selectively applied to the surface of the printhead and in which the immiscible fluid caps a number of nozzles defined within the printhead. A printer may comprise a printhead comprising a number of nozzles, an immiscible fluid applicator, and a processor to instruction the immiscible fluid applicator to apply a layer of immiscible fluid to the surface of the printhead.

In some examples, a method includes, in response to a fluid firing unit being operated according to a normal printing mode, applying a first voltage to the fluid firing unit to fire the fluid firing unit during a printing operation. The method further includes determining, using a sensor, whether a predetermined condition is met, and in response to determining that the predetermined condition is met, operating the fluid firing unit according to a recovery mode in which a second voltage higher than the first voltage is applied to the fluid firing unit to clean the fluid firing unit.

According to an embodiment, an electrospinning head includes a nozzle and an uneven surface. The nozzle is made from an electrically conductive material, and a flow path is formed inside the nozzle. On the outer surface of the nozzle, an ejection port capable of ejecting a material liquid supplied to the flow path is formed. The uneven surface is formed in the vicinity of the projection port on the outer surface of the nozzle, and an uneven shape of the uneven surface is formed around the entire circumference of the circumferential direction of the nozzle and is along the extending direction of the flow path.

According to an embodiment, an electrospinning head includes a nozzle and an uneven surface. The nozzle is made from an electrically conductive material, and a flow path is formed inside the nozzle. On the outer surface of the nozzle, an ejection port capable of ejecting a material liquid supplied to the flow path is formed. The uneven surface is formed in the vicinity of the projection port on the outer surface of the nozzle, and an uneven shape of the uneven surface is formed around the entire circumference of the circumferential direction of the nozzle and is along the extending direction of the flow path.

An inkjet printing apparatus includes a stage on which a target substrate is mounted, and an inkjet head positioned above the stage, wherein the inkjet head includes an ejection part including a plurality of nozzles that spray ink containing a plurality of particles, a filter part disposed above the ejection part, and selectively passing the plurality of particles, and an electric field generating electrode that is disposed in the filter part and generates an electric field in the filter part.

An inkjet recording apparatus 100 which records on a transferred recording medium X by an inkjet scheme, wherein the inkjet recording apparatus 100 includes guide rolls R for guiding the recording medium X, the recording medium X being negatively charged, recording units 1, 2, 3, and 4 formed of a plurality of recording heads 1a, 2a, 3a, and 4a for spraying ink onto the recording medium X, and a conductive frame unit 11 for supporting the recording heads 1a, 2a, 3a, and 4a, the recording heads 1a, 2a, 3a, and 4a and the conductive frame unit 11 having a continuity relation and the recording heads 1a, 2a, 3a, and 4a being grounded via the conductive frame unit 11.

An inkjet recording apparatus 100 which records on a transferred recording medium X by an inkjet scheme, wherein the inkjet recording apparatus 100 includes guide rolls R for guiding the recording medium X, the recording medium X being negatively charged, recording units 1, 2, 3, and 4 formed of a plurality of recording heads 1a, 2a, 3a, and 4a for spraying ink onto the recording medium X, and a conductive frame unit 11 for supporting the recording heads 1a, 2a, 3a, and 4a, the recording heads 1a, 2a, 3a, and 4a and the conductive frame unit 11 having a continuity relation and the recording heads 1a, 2a, 3a, and 4a being grounded via the conductive frame unit 11.

In some examples, a method includes, in response to a fluid firing unit being operated according to a normal printing mode, applying a first voltage to the fluid firing unit to fire the fluid firing unit during a printing operation. The method further includes determining, using a sensor, whether a predetermined condition is met, and in response to determining that the predetermined condition is met, operating the fluid firing unit according to a recovery mode in which a second voltage higher than the first voltage is applied to the fluid firing unit to clean the fluid firing unit.