A recording apparatus includes a first nozzle row and a second nozzle row, and a control unit configured to control ejection of liquid, the control unit is configured to cause the nozzle row to perform scan of ejecting the liquid while moving, and when recording a first pattern including a first overlapping region and a first normal region by controlling the first nozzle row and recording a second pattern including a second overlapping region and a second normal region by controlling the second nozzle row, the first overlapping region is formed at a position overlapping the second normal region as viewed in a longitudinal direction, the first overlapping region being an overlapping region where a raster line is formed by performing the scan m times, the first normal region being where the raster line is formed by performing the scan n times, n being smaller than m.

Provided are a control unit that predicts the life of an inkjet head unit and maximizes its life to be used, and a substrate treating apparatus including the same. The control unit performs maintenance of an inkjet head unit for discharging a substrate treatment liquid onto a substrate and comprises a count module for counting the number of discharges for each nozzle of the inkjet head unit, a comparison module for comparing the number of discharges with a reference value to determine whether the number of discharges is equal to or greater than the reference value, and an evaluation module for evaluating whether a life of the inkjet head unit has reached a usable life based on whether the number of discharges of each nozzle is equal to or greater than the reference value.

There is provided a printing apparatus including: a nozzle configured to discharge a liquid by an energy generating element; a selector configured to select, based on a print job, a driving waveform corresponding to a printing method indicated by the print job, from a plurality of driving waveforms different from each other; a signal generator configured to generate a time division multiplex signal, based on data indicating the driving waveform selected by the selector; and a separator configured to separate a driving waveform signal indicating the driving waveform selected by the selector from the time division multiplex signal generated by the signal generator. The energy generating element is configured to be driven by the driving waveform signal separated by the separator.

In an image forming apparatus, a recording head ejects ink corresponding to an image to be printed, using arranged nozzles. A control unit determines nozzles corresponding to the image to be printed, correspondingly to a position of a print sheet, and causes the recording head to eject ink from the nozzles. A correction processing performs a correction process corresponding to each of ink ejection malfunction positions in the image. Further, the correction processing unit (a) sets the ink ejection malfunction positions as targets of the correction process in advance, and (b) excludes from the targets on the basis of a sheet size of the print sheet an ink ejection malfunction position corresponding to a nozzle that is not used for the print sheet among nozzles corresponding to the plural ink ejection malfunction positions and thereafter performs the correction process for the targets.

A liquid ejection head includes an ejection-port defining member and a substrate having at least three liquid supply openings arranged in an array direction. The substrate has at least one groove in a region between ends of the liquid supply openings and an edge of the substrate. The groove extends from and communicates with the end of at least one of two outermost liquid supply openings of the liquid supply openings in the array direction. The groove extends at least to a position where the groove is superposed on the liquid supply opening next to the liquid supply opening communicating with the groove in an extending direction in which the liquid supply openings extend.

A maintenance method for a liquid discharging apparatus including a liquid discharging head. The liquid discharging apparatus executes a printing process including a discharging process in which the liquid discharged from the liquid discharging head lands on the medium, and a maintenance process in which the liquid is discarded from the liquid discharging head. The maintenance method includes: counting a unit period number, which is the number of ended unit periods among a plurality of unit periods obtained by dividing a period required for the printing process in accordance with a first condition; executing the maintenance process when the unit period number reaches a defined number; acquiring viscosity information related to viscosity of the liquid inside the liquid discharging head; and decreasing the unit period number when the viscosity information satisfies a second condition.

The inventive concept provides an inkjet printing method. The inkjet printing method for discharging an ink on a substrate using a head having a plurality of nozzles formed thereon includes determining a grade of nozzles by measuring a discharge performance of the nozzles, which is a grading step; selecting a use nozzle that can participate in printing the substrate among the nozzles based on the grade determined at the grading step, which is a nozzle selecting step; and discharging the ink on the substrate using at least one nozzle among use nozzles, which is a printing step.

In some examples, a fluid dispensing device includes a reservoir containing a fluid, fluidic actuators, and an interface to receive a data packet comprising information to control activation of the fluidic actuators, the data packet comprising a random number generated by a random number generator.

In a printing method using an ink jet head, a chemical liquid may be discharged onto a substrate from a plurality of nozzles of the ink jet head. Discharging numbers of the chemical liquid from the plurality of nozzles may be identified and a cumulative discharging number of the chemical liquid from the plurality of nozzles may be calculated. The cumulative discharging number of the chemical liquid may be compared with a previously set limit discharging number of the ink jet head. A replacement time of the ink jet head may be determined if the cumulative discharging number of the chemical liquid exceeds the previously set limit discharging number.

A print element substrate, comprising a plurality of heating elements, a plurality of detection elements, each configured to detect a temperature of a corresponding heating element, a first current generation unit, a second current generation unit, and a signal output unit, wherein one of the first and second current generation units supplies a current to a first detection element, the other supplies a current to a second detection element, and the signal output unit outputs a signal according to a potential difference between one terminal of the first detection element on a side where a potential variation occurs upon supply of the current and one terminal of the second detection element on a side where a potential variation occurs upon supply of the current.