A microfluidic device has a chamber; a fluidic access channel in fluidic connection with the chamber; a plurality of nozzle apertures in fluidic connection with the chamber; and an actuator, operatively coupled to the fluid containment chamber and configured to cause ejection of drops of fluid through the nozzle apertures in an operating condition of the microfluidic device. The chamber has an elongated shape, with a length and a maximum width, wherein an aspect ratio between the length and the maximum width of the chamber is at least 3:1. The nozzle apertures are configured to generate, in use, a plurality of drops having a total drop volume, wherein a ratio total drop volume to a chamber volume is at least 15%.

Ink is circulated through a circulation flow path between a print head and an ink tank. Detection operation for detecting an ink ejection state in an ejection opening in the print head is performed. The ink circulation and the detection operation are simultaneously performed by performing the detection operation in response to a start of the ink circulation.

A liquid ejection head includes a flow channel structure, a supply channel structure, and a particular heater. The flow channel structure defines an ejection channel that leads liquid toward a plurality of nozzles arranged in a nozzle row along a first direction. The supply channel structure defines a supply channel configured to allow liquid to flow therefrom to the ejection channel. The particular heater is configured to heat liquid. The flow channel structure is made of inorganic material having a higher thermal conductivity than material used for the supply channel structure. The flow channel structure includes an end portion protruding outward relative to a side surface of the supply channel structure. The particular heater is disposed at the end portion of the flow channel structure.

Provided is a liquid ejection apparatus, liquid ejection method, dispensing apparatus, and compound introduction apparatus capable of inhibiting contamination of a liquid after being ejected. The liquid ejection apparatus has an ejection unit having an ejection part and an ejection energy generation element that ejects a liquid from the ejection part by using a principle of inkjet ejection into an internal space in a storage part capable of storing the ejected liquid. When ejecting the liquid, the ejection unit covers an opening portion of the storage part to thereby screen the internal space in the storage part from an external space.

Ink is circulated through a circulation flow path between a print head and an ink tank. Detection operation for detecting an ink ejection state in an ejection opening in the print head is performed. The ink circulation and the detection operation are simultaneously performed by performing the detection operation in response to a start of the ink circulation.

An image forming apparatus 101 capable of performing printing with a high image quality, and a control method of the image forming apparatus 101 are provided. For this purpose, a threshold value Dt is preliminarily set that allows printing without occurrence of blur, for each of preliminarily set monitoring areas A. In the case where a print duty for each of the monitoring areas A has exceeded the threshold value Dt, an ejection frequency of ink and conveying speed of a print medium are reduced in association therebetween.

A liquid ejection head includes a flow channel structure, a supply channel structure, and a particular heater. The flow channel structure defines an ejection channel that leads liquid toward a plurality of nozzles arranged in a nozzle row along a first direction. The supply channel structure defines a supply channel configured to allow liquid to flow therefrom to the ejection channel. The particular heater is configured to heat liquid. The flow channel structure is made of inorganic material having a higher thermal conductivity than material used for the supply channel structure. The flow channel structure includes an end portion protruding outward relative to a side surface of the supply channel structure. The particular heater is disposed at the end portion of the flow channel structure.

A liquid ejection head is provided. The liquid ejection head includes at least two nozzle lines configured to have a plurality of nozzles for ejecting liquid disposed in respective lines, a plurality of individual liquid chambers configured to be in communication with corresponding nozzles of the nozzle lines, and at least two circulation channels corresponding to the nozzle lines, configured to be in communication with the individual liquid chambers. The at least two circulation channels are in communication with each other through a bridging channel disposed in a direction intersecting with the nozzle line direction, and the bridging channel and the circulation channels are disposed at different positions in a thickness direction of a member which forms the bridging channel and the circulation channels.

Ink is circulated through a circulation flow path between a print head and an ink tank. Detection operation for detecting an ink ejection state in an ejection opening in the print head is performed. The ink circulation and the detection operation are simultaneously performed by performing the detection operation in response to a start of the ink circulation.

An ink supply unit supplying ink from an ink tank to a recording head, includes: a component including a pump by which ink is supplied and having an abutment portion constituted by a laser light absorbing material; a plate having a first surface capable of abutting against the abutment portion, a second surface opposite to the first surface, and a channel forming unit that surrounds an opening passing through the plate from the first surface to the second surface and projects from the second surface; a sealing member that seals the opening; and an ink channel from a first abutment place of a side of the second surface where the abutment portion abuts against the first surface around the opening, and from a second abutment place of the side of the second surface where the sealing member abuts against the channel forming unit.