Abstract: An ink jet printer in which hardened ink is readily and reliably removed from a nozzle plate. The ink jet printer includes a print head having a plural number of nozzle openings arrayed in the width direction of a recording paper, a head drive circuit for selectively outputting a first signal to cause a stream of ink droplets at a speed suitable for print and a second signal to cause ink to ooze through each nozzle opening, and a cleaning device with a rubbing function and which is usually positioned in a nonprinting region, but is movable in the longitudinal direction of the print head and with respect to a nozzle plate. In a cleaning mode, the cleaning device is operated while oozing ink from the nozzle openings. The hardened ink on the nozzle plate is dissolved by the oozing ink, and then removed therefrom through the rubbing and wiping operations of the cleaning device.

Abstract: An ink composition for ink jet recording is described comprising a pigment, a resin dispersant, a thermoplastic resin emulsion and water, wherein the weight ratio of the pigment to the resin dispersant is from 20:1 to 5:2. The foregoing ink composition is little susceptible to irregular bleeding on a recording medium, undergoes no change in physical properties and jettability and no precipitation of solid matter and exhibits an excellent redispersibility.

Abstract: The recording device of an ink jet type comprises a drive voltage generation circuit which, in synchronization with a timing signal given from outside, generates a first drive voltage having a trapezoidal wave form, a drive circuit which outputs a first drive voltage to a piezo-vibrator in accordance with a printing signal given from outside and also, in synchronization with the timing signal, outputs a second drive voltage, which is used to generate such a small pulse that cannot jet out ink drops from a nozzle opening, to the piezo-vibrator in which a non-printing condition has continued for one or more cycles, and control means which stops the application of the small pulse when the time of application of the small pulse after completion of a printing operation exceeds a given time.

Abstract: With an ink jet recording head (8) comprising two common ink chambers (26) and (27) communicating with both sides of a pressure generation chamber (24) and ink supply ports (30) and (31) where ink flows into the common ink chambers (26) and (27) from the outside, one ink supply port (30) is connected to a subtank (10) and the other ink supply port (31) is connected to an ink cartridge (6). The subtank (10) is replenished with ink through the ink jet recording head (8). Since ink reversely flows into the ink cartridge (6) via the recording head (8) from the subtank (10) due to the head difference, ink in the recording head (8) can be forcibly circulated without complicating a flow passage configuration.

Abstract: An ink jet printer in which hardened ink is readily and reliably removed from a nozzle plate. The ink jet printer includes a print head having a plural number of nozzle openings arrayed in the width direction of a recording paper, a head drive circuit for selectively outputting a first signal to cause a stream of ink droplets at a speed suitable for print and a second signal to cause ink to ooze through each nozzle opening, and a cleaning device with a rubbing function and which is usually positioned in a nonprinting region, but is movable in the longitudinal direction of the print head and with respect to a nozzle plate. In a cleaning mode, the cleaning device is operated while oozing ink from the nozzle openings. The hardened ink on the nozzle plate is dissolved by the oozing ink, and then removed therefrom through the rubbing and wiping operations of the cleaning device.

Abstract: Disclosed is an ink-jet type recording device that includes drive signal generation circuit 84 for generating a trapezoidal drive signal in synchronization with a timing signal applied from an external device, switching transistors respectively for outputting a drive signal to piezoelectric vibrators in accordance with a printing signal applied from an external device, and control signal generation means for generating a pulse signal to turn on the switching transistors so that only a portion of the drive signal is output to any piezoelectric vibrators set in a non-printing condition in synchronization with a timing signal. This portion of the drive signal is applied to the piezoelectric vibrators belonging to those nozzle openings that should not jet out ink droplets in accordance with the pulse signal, so that menisci in the nozzle openings are merely vibrated slightly, respectively.

Abstract: A printer using a line-type ink jet recording head. The line-type head has pressure producing chambers formed by dividing nozzle openings extending in a recording paper width direction with vertical side walls and upper and lower ink flow paths which communicate with each other through the pressure producing chambers and extend in a horizontal direction. Each ink flow path has an inlet for replenishing ink and an outlet for discharging the ink. A plurality of pressure producing elements are provided for applying varied pressures to the pressure producing chambers for jetting ink droplets. A sealing member selectively seals the nozzle openings by abutting on the nozzle openings when the recording head has been evacuated to a predetermined position.

Abstract: The present invention disclosed herein provides a hot-melt ink composition that can provide a good fixing strength and a high quality of print independently of the kinds of recording media.

Abstract: A hot-melt ink composition for an ink jet printer, comprising a coloring agent, and a vehicle which comprises a dialkylbenzenesulfonamide, a monoalkylbenzenesulfonamide, and a resin; and a hot-melt ink composition comprising from 10 to 30 wt. % of a coloring agent, and a vehicle. These ink compositions can produce high quality images which have improved resistance to abrasion and are free from blooming.

Abstract: An ink composition for ink-jet printing, capable of producing a high-quality image without causing blur, comprising, as essential components, a coloring component and a dispersion medium in which the coloring component is homogeneously dispersed and retained, characterized in that the coloring component is insoluble in the dispersion medium and is dispersed therein in the state of finely divided particles of a size of 0.01 .mu.m or more, that the dispersion medium comprises a liquid having a surface tension at 25.degree. C. of 50 dyn/cm or less, and that the ink composition has the property that the dispersion medium immediately separates from the coloring component at the instant when the ink composition is deposited on an image-recording material.

Abstract: An ink composition particularly well suited for use in an ink jet printer wherein the ink is jetted at temperatures higher than room temperature. The ink composition includes a metallic complex solvent dye coloring material dispersed in a vehicle of at least one high molecular weight alkyl amine, at least one high molecular weight fatty acid and carnauba wax.