An apparatus and method configured to eject an electrically charged liquid. The apparatus and method include a liquid-ejecting apparatus including a reservoir for storing a liquid, an electrically conductive faceplate for ejecting the liquid, a plurality of channels connecting the reservoir to the electrically conductive faceplate, and a voltage source to change and maintain an electric potential difference between the liquid and the electrically conductive faceplate during ejection from the electrically conductive faceplate.

A system and method for three-dimensionally printing high viscosity materials using electrohydrodynamics is provided. The system uses a relatively low voltage electric field to draw high viscosity polymers (not in solution) from a nozzle to form three-dimensional objects with lines less than 10 microns in width. Pressurized gas at the nozzle outlet can be used to print large size/dimension parts, instead of or in addition to the electric field to draw the polymers from the nozzle.

An ink jet recording apparatus includes a charging electrode that charges ink particles ejected from a nozzle, a deflecting electrode that deflects the ink particles charged by the charging electrode, an operating unit that inputs and sets printing conditions for performing the printing, and a control unit, and the control unit receives a moving distance in a direction in which a printing target is conveyed from the operating unit, calculates the number of non-printing particles on the basis of the moving distance, and performs control for changing to a dot pattern in which the number of non-printing particles are inserted.

A method for operating a printhead of a continuous inkjet printer comprising: producing at least one ink jet in a cavity of the print head; electrostatically separating drops or sections of one or more of the jet intended for printing from drops or sections that do not serve for printing; exiting from the cavity drops or sections of ink intended for printing, through a slot open on the outside of the cavity; and circulating at least one flow of air along the outlet slot of the cavity in a direction essentially perpendicular to at least one jet of ink emitted by the printhead and intended for printing. The air having a water vapor pressure lower than the water vapor pressure defined by 100% relative humidity at the coldest temperature of the printer.

A method for operating a printhead of a continuous inkjet printer comprising: producing at least one ink jet in a cavity of the print head; electrostatically separating drops or sections of one or more of the jet intended for printing from drops or sections that do not serve for printing; exiting from the cavity drops or sections of ink intended for printing, through a slot open on the outside of the cavity; and circulating at least one flow of air along the outlet slot of the cavity in a direction essentially perpendicular to at least one jet of ink emitted by the printhead and intended for printing. The air having a water vapor pressure lower than the water vapor pressure defined by 100% relative humidity at the coldest temperature of the printer.

In order to suppress adherence of ink splash to an electrode and ink contamination of surrounding environment, in a printing system, there is provided a continuous type ink jet printer having a nozzle for jetting ink in the form of particles, a charging electrode for electrically charging the jetted ink particles, and a deflection electrode for deflecting the charged ink particles. The system includes a printing section for printing an object to be printed with the ink particles jetted from the nozzle and a charging section configured to charge at least one of the printing object prior to its printing by the printing section and surrounding atmosphere in which the printing on the printing object is to be effected by the printing section with a polarity opposite to a polarity of the charge provided to the ink particles by the charging electrode.

A drop-on-demand printing method comprising performing the following steps in a printing head: discharging a first primary drop of a first liquid from a first nozzle outlet to move along a first path (pA) with a first speed; discharging a second primary drop of a second liquid from a second nozzle outlet to move along a second path (pB) with a second speed, lower than the first speed, wherein the second path (pB) is inclined with respect to the first path (pB) along an axis inclined at an angle () from 3 to 60 degrees and crosses the first path (pA) at a connection point; controlling the flight of the first primary drop and the second primary drop to combine the first primary drop with the second primary drop into a combined drop at the connection point so that a chemical reaction is initiated between the first liquid of the first primary drop and the second liquid of the second primary drop; applying electric charge to the combined drop; wherein the path of flight (pC) of the combined drop is altered no more than 20 degrees from the axis of the path of flight (pA) of the first primary drop; and controlling the path of flight (pC) of the combined drop with applied electric charge by deflecting electrodes.

A drop-on-demand printing method comprising performing the following steps in a printing head: discharging a first primary drop of a first liquid from a first nozzle outlet to move along a first path (pA) with a first speed; discharging a second primary drop of a second liquid from a second nozzle outlet to move along a second path (pB) with a second speed, lower than the first speed, wherein the second path (pB) is inclined with respect to the first path (pB) along an axis inclined at an angle () from 3 to 60 degrees and crosses the first path (pA) at a connection point; controlling the flight of the first primary drop and the second primary drop to combine the first primary drop with the second primary drop into a combined drop at the connection point so that a chemical reaction is initiated between the first liquid of the first primary drop and the second liquid of the second primary drop; applying electric charge to the combined drop; wherein the path of flight (pC) of the combined drop is altered no more than 20 degrees from the axis of the path of flight (pA) of the first primary drop; and controlling the path of flight (pC) of the combined drop with applied electric charge by deflecting electrodes.

An electrostatic deflection inkjet printer has a main printer body separated by a vapor barrier into an electrical region and a fluid region. Electrically operated valves are provided in the fluid region. Control circuitry for deciding when to operate the valves is provided in the electrical region. Valve drive circuitry, for generating drive currents for the valves, is provided in the fluid region and is in data communication with the control circuitry via wiring, which may be a serial bus, that passes through the vapor barrier. This reduces the number of electrical connections that need to pass through the vapor barrier. A circuit carrier for the valve drive circuitry may be mounted on a valve block for the valves, and an electrically insulating material may cover the circuit carrier. The electrically insulating material may extend partially or wholly around the valve block.

An electrostatic deflection inkjet printer has a main printer body separated by a vapor barrier into an electrical region and a fluid region. Electrically operated valves are provided in the fluid region. Control circuitry for deciding when to operate the valves is provided in the electrical region. Valve drive circuitry, for generating drive currents for the valves, is provided in the fluid region and is in data communication with the control circuitry via wiring, which may be a serial bus, that passes through the vapor barrier. This reduces the number of electrical connections that need to pass through the vapor barrier. A circuit carrier for the valve drive circuitry may be mounted on a valve block for the valves, and an electrically insulating material may cover the circuit carrier. The electrically insulating material may extend partially or wholly around the valve block.