Abstract: A liquid discharge head includes: a substrate, where a recording element is disposed; and a discharge orifice forming member, where a discharge orifice, facing the recording element, and configured to discharge the liquid, is formed. The liquid discharge head has a pressure chamber, a first liquid channel configured to supply liquid to the pressure chamber, and a second liquid channel configured to recover liquid from the pressure chamber. The substrate has a liquid supply channel connected to the first liquid channel to supply liquid to the first liquid channel, and a liquid recovery channel connected to the second liquid channel, to recover liquid from the second liquid channel. Pressure at an inlet portion of the liquid supply channel is higher than pressure at an outlet portion of the liquid recovery channel, and a flow velocity of liquid within the pressure chamber is 3 to 140 mm/s.

Abstract: A liquid discharge head includes: a substrate, where a recording element is disposed; and a discharge orifice forming member, where a discharge orifice, facing the recording element, and configured to discharge the liquid, is formed. The liquid discharge head has a pressure chamber, a first liquid channel configured to supply liquid to the pressure chamber, and a second liquid channel configured to recover liquid from the pressure chamber. The substrate has a liquid supply channel connected to the first liquid channel to supply liquid to the first liquid channel, and a liquid recovery channel connected to the second liquid channel, to recover liquid from the second liquid channel. Pressure at an inlet portion of the liquid supply channel is higher than pressure at an outlet portion of the liquid recovery channel, and a flow velocity of liquid within the pressure chamber is 3 to 140 mm/s.

Abstract: A liquid ejection head including first and second recording element substrates adjacent in a direction intersecting a relative movement direction include ejection opening rows that include ejection openings arranged in the intersecting direction. A straight line connecting the ejection openings in end portions on a second recording element substrate side in the first recording element substrate and a straight line connecting the ejection openings in end portions on a first recording element substrate side in the second recording element substrate are inclined towards a middle area side of the first recording element substrate, and arrangement intervals of the ejection openings in an end portion area on the second recording element substrate side of a first ejection opening row is larger than arrangement intervals of the ejection openings in an end portion area on the first recording element substrate side of a second ejection opening row.

Abstract: A printing apparatus measures a temperature of an electrothermal transducer by a corresponding temperature detection element, detects, based on the measured temperature, a peak voltage which indicates a point of change, from a state where ink is discharged normally from a printhead to a state where the ink is not discharged from the printhead, and compares the peak voltage with a threshold value. The measurement, detection, and comparison are repeated until the peal voltage becomes equal to or more than the threshold value. Energy supplied to the electrothermal transducer at a time in which the peak voltage is determined to be equal to or more than the threshold is determined to be minimum discharge energy.

Abstract: A liquid discharge head includes a recording element configured to generate thermal energy and a discharge orifice disposed at a position facing the recording element. A bubble is generated in liquid by the thermal energy, liquid between the bubble and the discharge orifice is discharged from the discharge orifice by the pressure of the generated bubble, and the bubble communicates with the atmosphere on the outside of the discharge orifice.

Abstract: A liquid discharge apparatus includes a liquid discharge head including a discharge port configured to discharge liquid and a discharge port surface provided with the discharge port. A head cleaning member including a contact portion contacts the discharge port surface, and is configured to cause the contact portion to contact the discharge port surface and to move relative to the discharge port surface in order to clean adherents attached to the discharge port surface. The discharge port includes a plurality of protrusion portions extending toward a discharge port inner side. The contact portion includes a fiber, and the fiber in the contact portion includes a portion having a size greater than a minimum protrusion distance among protrusion distances between the protrusion portions.

Abstract: A print element substrate and a liquid ejection head capable of suppressing degradation of a print quality caused by a white stripe/black stripe etc., is actualized without using a high degree of microfabrication technology. As a result of asymmetric deformation by swelling in a direction of relative movement to a print medium, print elements having different liquid droplet ejection directions are made to coexist and arrayed for that purpose.

Abstract: A liquid discharging head includes a discharge port that discharges a liquid, a pressure chamber that communicates with the discharge port, and an energy generating element that is disposed in the pressure chamber. In the liquid discharging head, the discharge port is provided with a plurality of projections that project towards a central portion of the discharge port from an inner peripheral edge of the discharge port, and an interval between the projections at a location where the projections are closest to each other is 5 ?m or less.

Abstract: A liquid ejection head including first and second recording element substrates adjacent in a direction intersecting a relative movement direction include ejection opening rows that include ejection openings arranged in the intersecting direction. A straight line connecting the ejection openings in end portions on a second recording element substrate side in the first recording element substrate and a straight line connecting the ejection openings in end portions on a first recording element substrate side in the second recording element substrate are inclined towards a middle area side of the first recording element substrate, and arrangement intervals of the ejection openings in an end portion area on the second recording element substrate side of a first ejection opening row is larger than arrangement intervals of the ejection openings in an end portion area on the first recording element substrate side of a second ejection opening row.

Abstract: A printing element substrate includes a substrate, an energy generating element, and an ejection-port formed member. The energy generating element is disposed on one surface of the substrate and configured to generate energy for use in ejecting liquid. The ejection-port formed member includes ejection ports that eject the liquid. A protrusion protruding toward inside of each of the ejection ports is provided on an inner surface of the ejection port. In a surface of the ejection-port formed member remote from the substrate, a tip portion of the protrusion is positioned closer to the substrate than an outer periphery of the ejection port.

Abstract: A liquid discharge head includes: a substrate, where a recording element is disposed; and a discharge orifice forming member, where a discharge orifice, facing the recording element, and configured to discharge the liquid, is formed. The liquid discharge head has a pressure chamber, a first liquid channel configured to supply liquid to the pressure chamber, and a second liquid channel configured to recover liquid from the pressure chamber. The substrate has a liquid supply channel connected to the first liquid channel to supply liquid to the first liquid channel, and a liquid recovery channel connected to the second liquid channel, to recover liquid from the second liquid channel. Pressure at an inlet portion of the liquid supply channel is higher than pressure at an outlet portion of the liquid recovery channel, and a flow velocity of liquid within the pressure chamber is 3 to 140 mm/s.

Abstract: A recording element board includes a discharge orifice configured to discharge liquid, a pressure chamber communicating with the discharge orifice, a recording element configured to generate thermal energy to cause bubbling of the liquid, the recording element being disposed in the pressure chamber facing the discharge orifice, and a substrate on which the recording element is formed. When the recording element is driven and the liquid of within the pressure chamber is discharged, a generated bubble communicates with the atmosphere. A discharge orifice projection region where the discharge orifice has been projected on the substrate includes a region includes a region extending beyond a heat-generating region projection region where the heat-generating region of the recording element has been projected on the substrate, the outline of the discharge orifice projection region is circumscribed by the outline of the heat-generating region projection region.

Abstract: A liquid discharge apparatus includes a liquid discharge head including a discharge port configured to discharge liquid and a discharge port surface provided with the discharge port. A head cleaning member including a contact portion contacts the discharge port surface, and is configured to cause the contact portion to contact the discharge port surface and to move relative to the discharge port surface in order to clean adherents attached to the discharge port surface. The discharge port includes a plurality of protrusion portions extending toward a discharge port inner side. The contact portion includes a fiber, and the fiber in the contact portion includes a portion having a size greater than a minimum protrusion distance among protrusion distances between the protrusion portions.

Abstract: A liquid discharge head includes: a substrate, where a recording element is disposed; and a discharge orifice forming member, where a discharge orifice, facing the recording element, and configured to discharge the liquid, is formed. The liquid discharge head has a pressure chamber, a first liquid channel configured to supply liquid to the pressure chamber, and a second liquid channel configured to recover liquid from the pressure chamber. The substrate has a liquid supply channel connected to the first liquid channel to supply liquid to the first liquid channel, and a liquid recovery channel connected to the second liquid channel, to recover liquid from the second liquid channel. Pressure at an inlet portion of the liquid supply channel is higher than pressure at an outlet portion of the liquid recovery channel, and a flow velocity of liquid within the pressure chamber is 3 to 140 mm/s.

Abstract: A recording element board includes a discharge orifice configured to discharge liquid, a pressure chamber communicating with the discharge orifice, a recording element configured to generate thermal energy to cause bubbling of the liquid, the recording element being disposed in the pressure chamber facing the discharge orifice, and a substrate on which the recording element is formed. When the recording element is driven and the liquid of within the pressure chamber is discharged, a generated bubble communicates with the atmosphere. A discharge orifice projection region where the discharge orifice has been projected on the substrate includes a region includes a region extending beyond a heat-generating region projection region where the heat-generating region of the recording element has been projected on the substrate, the outline of the discharge orifice projection region is circumscribed by the outline of the heat-generating region projection region.

Abstract: A liquid discharge head includes a recording element configured to generate thermal energy and a discharge orifice disposed at a position facing the recording element. A bubble is generated in liquid by the thermal energy, liquid between the bubble and the discharge orifice is discharged from the discharge orifice by the pressure of the generated bubble, and the bubble communicates with the atmosphere on the outside of the discharge orifice.

Abstract: A recording element substrate includes: a substrate on which a plurality of energy generating elements that generate energy used for ejecting liquid are arranged side by side, an ejection port forming member in which ejection ports are formed at positions corresponding to the plurality of energy generating elements, a plurality of supply passages which are channels extending in a thickness direction of the substrate and through which liquid is supplied to the energy generating elements, and a support member that is formed between the substrate and the ejection port forming member and supports the ejection port forming member, in which supply ports that are apertures of the plurality of supply passages are linearly arranged side by side on the substrate, and a plurality of support members are provided side by side between adjacent supply ports on the substrate in a direction in which the supply ports are aligned.

Abstract: A liquid discharge head includes a recording element configured to generate thermal energy and a discharge orifice disposed at a position facing the recording element. A bubble is generated in liquid by the thermal energy, liquid between the bubble and the discharge orifice is discharged from the discharge orifice by the pressure of the generated bubble, and the bubble communicates with the atmosphere on the outside of the discharge orifice.

Abstract: A liquid discharging head includes a discharge port that discharges a liquid, a pressure chamber that communicates with the discharge port, and an energy generating element that is disposed in the pressure chamber. In the liquid discharging head, the discharge port is provided with a plurality of projections that project towards a central portion of the discharge port from an inner peripheral edge of the discharge port, and an interval between the projections at a location where the projections are closest to each other is 5 ?m or less.

Abstract: A discharge port array is inclined to a second direction B at an angle ? that satisfies a relation of tan ?=d2/(N×d1), where d1 is a distance between discharge ports within the discharge port array in the second direction B, and d2 is a distance between two adjacent discharge ports within each group in a first direction.