Matsushita Electric Industrial Co., Ltd.

Mitsuhide Matsuda

Hideaki Horio

Yutaka Miyazono

Kazumi Ohtsubo

Tomoyuki Noguchi

Tadashi Shiraishi

Takumi Inoue

Hiroshi Shibata

Masaharu Oyama

Takuma Takasu

Naoto Yoshida

Masaharu Ooyama

Masaya Iwasaki

There is provided an ink-jet printer for jetting ink drops through nozzle holes in which each of the nozzle holes is circular in section, a ratio,/,of a nozzle hole roundness of each of the nozzle holes,to a nozzle hole diameter of each of the nozzle holes,is not more than 0.2, and an amount of ink/jet which is jetted through each of the nozzle holes is not more than 20 pl. According to this ink-jet printer, a good printing quality can be obtained without impact-errors.

Ink jet printer

There is provided an ink-jet printer for jetting ink drops through nozzle holes in which each of the nozzle holes is circular in section, a ratio a/d of a nozzle hole roundness of each of the nozzle holes a to a nozzle hole diameter of each of the nozzle holes d is not more than 0.2, and an amount of ink/jet which is jetted through each of the nozzle holes is not more than 20 pl. According to this ink-jet printer, a good printing quality can be obtained without impact-errors.

There is provided an ink-jet printer for jetting ink drops through nozzle holes in which each of the nozzle holes is circular in section, a ratio a/d of a nozzle hole roundness of each of the nozzle holes a to a nozzle hole diameter of each of the nozzle holes d is not more than 0.2, and an amount of ink/jet which is jetted through each of the nozzles holes is not more than 20 pl. According to this ink-jet printer, a good printing quality can be obtained without impact-errors.

A pair of opposed electrodes are formed on a circuit substrate by photolithography, and an insulation film is formed on the circuit substrate to cover said electrodes therewith. An opening is formed through the insulation film in such a manner that areas of exposure of the pair of electrodes through the opening are substantially equal to each other. A nozzle fluid passage substrate, having a nozzle and a pressure chamber communicating with the nozzle, is placed on the circuit substrate through an adhesive layer in such a manner that the pressure chamber is disposed substantially coaxially with the opening. Then, the circuit substrate and the nozzle fluid passage substrate are bonded together through the adhesive layer by application of heat and pressure, thereby producing a ink jet head for a printer.

Ink jet head

An ink discharging device includes arrayed nozzle holes and corresponding ink flow paths leading thereto. An electrode is provided between the adjacent ink flow paths in such a manner as to be exposed to both of the adjacent ink flow paths so that each electrode works as a common electrode for both of the adjacent ink flow paths. By energizing a conductive ink between the electrodes within the corresponding ink flow path, a portion of the conductive ink is discharged through the corresponding nozzle hole.

Ink discharging device

A thin type ink jet cartridge consists of a passageway for holding ink, a thin type ink holder made of transparent material for accommodating the passageway, a graded scale put on the thin type of ink holder to quantitatively check the volume of the ink held in the passageway, ribs for structurally reinforcing the thin type ink holder, nozzles for discharging the ink held in the passageway at a recording paper, a shutter for covering the shutter when the ink is not discharged from the nozzles, a protecting plate for protecting the recording paper from contact with the nozzles by surrounding the nozzles positioned at a concave portion surrounded by the protecting plate.

Thin type of ink jet cartridge

A method for manufacturing an ink jet head which involves the steps of casting a first synthetic film on a metal film, etching the conductive metal to produce a pair of etched electrodes facing each other across an opening according to lithography and etching techniques, casting a second synthetic resin film being transparent on the etched electrodes and the first synthetic resin film, ablating both the first and second synthetic resin films with an excimer laser without damaging the electrodes to form both an expelling nozzle which penetrates the second synthetic resin film and an ink passageway which penetrates the first synthetic resin film through the opening, attaching an ink holding cap to the first synthetic resin film to hold conductive ink in a hollow portion thereof, and electrically connecting the etched electrodes with a voltage generator through electrical leads for applying a voltage generated in the voltage generator to the etched electrodes, wherein the etched electrodes project into the expelling nozzle. The conductive ink held in the ink holding cap is expelled from the nozzle through the ink passageway upon vaporization.

Method for manufacturing an ink jet head in which droplets of conductive

An ink-jet cartridge for ink-jet printers includes a nozzle-cleaning mechanism built in the cartridge itself for removing residual ink and foreign matter, such as dust and dirt including paper powder, from nozzles. Since the built-in nozzle-cleaning mechanism is replaced automatically when the cartridge is replaced, and since the replacement of the cartridge generally takes place before the nozzle-cleaning mechanism deteriorates mainly due to contamination with ink, the nozzles are always kept clean and a reliable printing operation with high quality printing is insured throughout the service life of the cartridge.

Ink-jet cartridge for ink-jet printers and ink-jet printer using the same

An improved ink-jet printer of the so-called current flow type wherein a current is passed through a conductive ink contained between a pair of electrodes so as to cause the ink to become vaporized and cause trapped gasses or bubbles to expand suddenly, exerting a sufficient pressure upon the ink to force a droplet of ink from a nozzle is disclosed, wherein at least one projection of electrically insulating material is disposed between the pair of electrode for increasing the density of the current at a position directly below a nozzle. With the projection thus provided, only a limited portion of the conductive ink participates in the generation of heat, and boiling of the conductive ink takes place only at the position directly below the nozzle. Accordingly, droplets of conductive ink are produced with minimum power consumption and can be ejected in a uniform direction. The position where boiling of the conductive ink takes place is remote from the electrodes, so that the electrodes are substantially free from cavitation and thermal shock and, hence, they have a long life span.

Ink-jet printer head

In an ink-jet printer of the type wherein a current is passed through a conductive ink contained between a pair of electrodes to cause the ink to become vaporized and cause trapped gasses or bubbles to expand suddenly, exerting a sufficient pressure upon the ink to force droplets of ink from a nozzle, a current value flowing between the electrodes is detected to determine the amount of wear of the electrodes, and when the detected current value is lower than a predetermined value, an alarm indicative of the replacement of the currently used ink-jet head is given and, at the same time, ejection of the ink from the nozzle is stopped. Thus, printing operation is always achieved with stable ejection of ink, guaranteeing high printing qualities.

Growing community of inventors

Fukuoka, Japan

Mitsuhide Matsuda