Droplet deposition apparatus comprising an array of fluid chambers defined by a pair of opposing chamber walls, and in fluid communication with a nozzle for droplet ejection therefrom; a cover member is joined to the edges of the chamber walls and thus seals one side of the chambers. The cover member has a ratio of cover thickness to chamber wall separation less than or equal to 1:1.

Droplet deposition apparatus

A high-quality image is printed with reduced bleeding in colors that may appear at a boundary between a black image and a color image. A head for ejecting black ink and a head for ejecting color ink perform three times of scanning while feeding is carried out therebetween for moving the printing medium by four pitches of ejection openings arranged on the heads, different ejection openings are caused to correspond to a scanning area, which corresponds to the four pitches, and multi-pass printing is performed to complete printing on the area. The black head completes printing of the black image, and then, the color head completes printing of the color image adjacent to the black image. The arrangement of ejection openings is determined so that between last scanning for completing printing of the black image and the first scanning for printing of the color image, scanning with no performing printing exists.

Ink jet printing apparatus and ink jet printing method

A liquid ink, drop-on-demand printhead includes a substrate having a plurality of drop-emitter orifices, an ink channel coupled to each of the orifices for delivery of a body of ink to the orifices at a pressure above ambient, thereby forming an ink meniscus at the orifices. Drop selection is effected by selectively delivering heat to ink which has been delivered to selectively addressed ones of the orifices, thereby causing a difference in meniscus position between ink in addressed and non-addressed orifices. A heater is suspended in each ink meniscus close to its surface when the meniscus is at its position in a non-addressed orifice, the heater being effective to heat the meniscus and to thereby reduce surface tension of the meniscus at selectively addressed orifices.

Ink printing apparatus with improved heater

An ink jet print device includes a passageway for flowing ink having an outlet for ejecting ink at one end. The passageway has a portion where the cross-sectional dimensions of the passageway change. A generating device which generates energy for ejecting ink from the outlet is disposed on a surface intersecting the passageway and defines a part of the portion where the cross-sectional dimensions of the passageway change.

Ink jet print device and print head or print apparatus using the same

An ink-jet recording head includes a discharge-port portion including a first discharge-port portion continuing from a discharge port, and a second discharge-port portion communicating the first discharge-port portion with a bubble generation chamber. The second discharge-port portion has an end surface that includes a border portion bordering the first discharge-port portion and is parallel to a main surface of an element substrate. The cross-sectional area of the second discharge-port portion, anywhere from an opening surface facing the bubble generation chamber to an end surface facing the first discharge-port portion, that is parallel to the main surface of the element substrate, is larger than the area of the border portion. The cross section of the opening surface of the second discharge-port portion has a length in a direction perpendicular to an arrangement direction of the discharge ports that is greater than its length in a direction parallel to the arrangement direction.

Ink jet recording head

A thermal ink jet printer is disclosed in which ink droplets are ejected from an orifice by the explosive formation of a vapor bubble within the ink supply due to the application of a two part electrical pulse to a resistor within the ink supply. The electrical pulse comprises a precurser pulse and a nucleation pulse; the precurser pulse preheats the ink in the vicinity of the resistor to a temperature below the boiling temperature of the ink so as to preheat the ink while avoiding vapor bubble nucleation within the ink supply and the subsequently occuring nucleation pulse very quickly heats the resistor to near the superheat limit of the ink.

Thermal ink jet printer

A thermal ink jet printer emits discrete drops of a variable volume in order to create a printed gray scale. A pulse train of packets of pulses is used to generate drops comprising packets of connected or merged droplets; the reciprocal of the pulse repetition rate is greater than the bubble collapse time and the pulse packet rate is less than the maximum single droplet emission rate of the print head. The individual droplets within the packet merge in flight to create a single drop whose volume depends upon the number of pulses contained within the pulse packet. The summing of impulses generated by the individual pulses is also useful so that drops of ink may be emitted by a resistor which is physically undersized for the particular ink being used.

Method and apparatus for generating a gray scale with a high speed thermal ink jet printer

A thermal ink jet printer (1) emits discrete drops of a variable volume in order to create a printed gray scale. A pulse train of packets of pulses (Figure 3) is used to generate drops comprising packets of connected or merged droplets; the reciprocal of the pulse repetition rate is greater than the bubble collapse time and the pulse packet rate is less than the maximum single droplet emission rate of the print head. The individual droplets within the packet merge in flight to create a single drop whose volume depends upon the number of pulses contained within the pulse packet. The summing of impulses generated by the individual pulses is also useful so that drops of ink may be emitted by a resistor (5) which is physically undersized for the particular ink being used.

Method of generating an N-tone gray scale with a thermal ink jet printer, and apparatus therefor

A side-shooting thermal ink jet printer is provided with a control circuit for permitting the ejection of ink droplets from printhead orifices at only certain times after the ejection of ink droplets from other orifices in the printhead so that crosstalk between orifices through the ink supply does not degrade the quality of the subsequently ejected ink droplets. A test circuit is provided for determining the optimum multiplex periods between ejection of ink droplets from adjacent orifices.

Christopher A. Tacklind

Papers

Thermal ink jet printer

Method and apparatus for generating a gray scale with a high speed thermal ink jet printer

Method of generating an N-tone gray scale with a thermal ink jet printer, and apparatus therefor

Method and apparatus for eliminating the effects of acoustic cross-talk in thermal ink jet printer

Verfahren zum austreiben eines fluessigkeitstroepfchens aus einer oeffnung eines kapillarkoerpers