Abstract: The invention provides a liquid ejection head equipped with an energy generating element generating energy utilized for ejecting a liquid, a liquid supply port provided at a surface on which the energy generating element is provided for supplying the liquid to the energy generating element, a liquid flow path for supplying the liquid to the energy generating element from the liquid supply port and a rib extending from the liquid supply port toward an inlet of the liquid flow path, wherein an end portion of the rib on the side of the liquid flow path is provided at a position deviated from a center line of the liquid flow path.

Abstract: The invention provides a liquid ejection head equipped with an energy generating element generating energy utilized for ejecting a liquid, a liquid supply port provided at a surface on which the energy generating element is provided for supplying the liquid to the energy generating element, a liquid flow path for supplying the liquid to the energy generating element from the liquid supply port and a rib extending from the liquid supply port toward an inlet of the liquid flow path, wherein an end portion of the rib on the side of the liquid flow path is provided at a position deviated from a center line of the liquid flow path.

Abstract: A liquid ejection head in which the adverse effect of a heating resistor element due to cavitation is reduced and a printing apparatus employing this liquid ejection head are provided. When a length of a heating resistor element in a direction in which ink is to be supplied is defined by L, the center of an ejection port is shifted, at a distance equal to or longer than L/7 toward a location of an ink supply port, from the center of the heating resistor element, viewed in a direction in which ink is to be ejected. When a length of the ejection portion in the direction in which ink is to be ejected is defined as l and a length of a bubble generation chamber in the direction in which the liquid is to be ejected is defined as h, l/h is equal to or less than 2.

Abstract: A liquid ejection head includes ejection ports for ejecting liquid, recesses respectively accommodating the ejection ports in the insides thereof, ejection sections operating as passages directed to the respective ejection ports, and liquid channels for supplying the respective ejection sections with liquid. The ejection sections and the liquid channels are arranged in rows extending in respective directions that intersect each other, and the connection sections respectively connecting the ejection sections and the corresponding liquid channels represent an elliptic contour having a major axis and a minor axis as viewed from the corresponding one of the ejection ports, while the recesses also represent an elliptic contour having a major axis and a minor axis.

Abstract: A liquid ejection head that the adverse effect of a heating resistor element due to cavitation is reduced and a printing apparatus employing this liquid ejection head are provided. When a length of a heating resistor element in a direction in which ink is to be supplied is defined by L, the center of an ejection port is shifted, at a distance of equal to or longer than L/7 toward a location of an ink supply port, from the center of the heating resistor element, viewed in a direction in which ink is to be ejected. When a length of the ejection portion in the direction in which ink is to be ejected is defined as l and a length of a bubble generation chamber in the direction in which the liquid is to be ejected is defined as h, l/h is equal to or smaller than 2.

Abstract: A liquid discharge head includes a plurality of discharge ports configured to discharge liquid, a supply port configured to retain the liquid to be discharged from the plurality of discharge ports, a first pressure chamber including a first energy generation element to discharge a predetermined amount of liquid droplets, a second pressure chamber including a second energy generation element to discharge an amount of liquid droplets greater than the predetermined amount, a first flow path through which the supply port and the first pressure chamber communicate with each other, and a second flow path through which the first pressure chamber and the second pressure chamber communicate with each other.

Abstract: An ink to be applied to a recording head having a common liquid chamber, pressure chambers developing pressure applied to the liquid, individual channels through which the liquid is introduced into the pressure chambers from the common liquid chamber, and a group of nozzles which communicate with the pressure chambers and eject the liquid, where first nozzles having short individual channels and second nozzles having long ones are alternately arranged at arrangement intervals of less than 30 ?m along one side or sides of the common liquid chamber, contains an aqueous medium, a surfactant and a coloring material. The aqueous medium consists of water and a water-soluble organic compound containing at least one alkanediol and has a surface tension of from 40 mN/m or more to less than 60 mN/m in an environment of temperature 25° C. and humidity 50%.

Abstract: The print head includes an energy generating element, a chamber for accommodating liquid, and an ejection opening arranged in a position corresponding to the energy generating element. The ejection opening includes at least one projection projecting inside of the ejection opening, the ejection opening having a first region between a front end of the projection and an inner wall of the ejection opening positioned at the shortest distance from the front end, and second regions positioned in both sides of the projection and different from the first region, and when a width of the projection at a chamber-side opening face is represented as a1 and the maximum width of the projection is represented as a2, a relation a1<a2 is established and the width of the projection decreases gradually or step by step from a position having the width of a2 to the chamber-side opening face.

Abstract: A liquid ejection head includes ejection ports for ejecting liquid, recesses respectively accommodating the ejection ports in the insides thereof, ejection sections operating as passages directed to the respective ejection ports, and liquid channels for supplying the respective ejection sections with liquid. The ejection sections and the liquid channels are arranged in rows extending in respective directions that intersect each other, and the connection sections respectively connecting the ejection sections and the corresponding liquid channels represent an elliptic contour having a major axis and a minor axis as viewed from the corresponding one of the ejection ports, while the recesses also represent an elliptic contour having a major axis and a minor axis.

Abstract: An ink to be applied to a recording head having a common liquid chamber, pressure chambers developing pressure applied to the liquid, individual channels through which the liquid is introduced into the pressure chambers from the common liquid chamber, and a group of nozzles which communicate with the pressure chambers and eject the liquid, where first nozzles having short individual channels and second nozzles having long ones are alternately arranged at arrangement intervals of less than 30 ?m along one side or sides of the common liquid chamber, contains an aqueous medium, a surfactant and a coloring material. The aqueous medium consists of water and a water-soluble organic compound containing at least one alkanediol and has a surface tension of from 40 mN/m or more to less than 60 mN/m in an environment of temperature 25° C. and humidity 50%.

Abstract: An ink to be applied to a recording head having a common liquid chamber, pressure chambers developing pressure applied to the liquid, individual channels through which the liquid is introduced into the pressure chambers from the common liquid chamber, and a group of nozzles which communicate with the pressure chambers and eject the liquid, where first nozzles having short individual channels and second nozzles having long ones are alternately arranged at arrangement intervals of less than 30 ?m along one side or sides of the common liquid chamber, contains an aqueous medium, a surfactant and a coloring material. The aqueous medium consists of water and a water-soluble organic compound containing at least one alkanediol and has a surface tension of from 40 mN/m or more to less than 60 mN/m in an environment of temperature 25° C. and humidity 50%.

Abstract: A liquid discharge head includes a plurality of discharge ports configured to discharge liquid, a supply port configured to retain the liquid to be discharged from the plurality of discharge ports, a first pressure chamber including a first energy generation element to discharge a predetermined amount of liquid droplets, a second pressure chamber including a second energy generation element to discharge an amount of liquid droplets greater than the predetermined amount, a first flow path through which the supply port and the first pressure chamber communicate with each other, and a second flow path through which the first pressure chamber and the second pressure chamber communicate with each other.

Abstract: A liquid ejection head is provided that is adapted, when the ejection of comparatively small ink droplets by one print head is required, to not only increase a printing speed and a printing resolution but also to prevent the occurrence of cavitation. The liquid ejection head includes: nozzles, for which heaters are formed to generate thermal energy used to eject ink; and bubble generation chambers, for which ejection ports are formed for ejecting ink upon the application of thermal energy provided by the heaters. Further, a partition wall is formed in each bubble generation chamber at a position opposite the ejection port.

Abstract: To provide an inkjet head which includes high-density nozzle rows and which does not easily cause an ejection failure due to adhesion of ink mist around ejection orifices when a high-density image of a secondary color is printed with a small number of paths. An inkjet head includes at least two or more types of nozzle rows that eject different amounts of ink. When A is the cross section, with respect to an ink supplying direction, of an ink supply path from each ejection orifice to a supply port and L is the length of the ink supply path, the value of A/L differs between the two or more types of nozzle rows. The nozzle row of which the value of A/L is small is disposed outside an area between the nozzle rows that eject a largest amount of ink and that are arranged next to each other.

Abstract: An objective is to provide an inkjet print apparatus and an inkjet print method capable of a print without concentration unevenness. To achieve the objective, in a multiple-pass print using mask patterns each having low-print-percentage areas and high-print-percentage areas, the print-percentage difference between high-print-percentage areas and low-print-percentage areas is cancelled out in left-edge and right-edge parts of an image to be printed.

Abstract: A printing apparatus prints on a printing medium by scanning a printhead having a plurality of nozzle arrays in a first direction and a second direction opposite to the first direction, and has a structure in which an air flow entering the nozzle array in the scan of the printhead in the first direction becomes larger than an air flow entering the nozzle array in the scan of the printhead in the second direction. The apparatus increases, in scanning in the second direction, discharge speed of ink discharged from at least one nozzle array arranged leeward in the scanning direction of the printhead from a predetermined position on the printhead in the scanning direction to be higher than or equal to the discharge speed of ink discharged from at least one nozzle array arranged windward in the scanning direction of the printhead from the predetermined position.

Abstract: An inkjet printing apparatus and an inkjet printing method are provided which can minimize air current disturbances that occur between the print head and the print medium and also minimize density unevenness caused by mask patterns. For this purpose, the 2-pass printing is performed such that the high printing ratio region and the low printing ratio region are alternated every pixel in the nozzle-arrayed direction and that adjoining groups of high printing ratio regions are separated from one another by a group of low printing ratio regions that forms a passage wide enough for air currents to pass through.

Abstract: While the print head is reduced in size, the adverse effect of air flows produced by ink droplets as they are ejected from a small number of ejection opening arrays is minimized. A small number of first ejection opening arrays eject one of three primary colors—cyan, magenta and yellow—and a large number of second and third ejection opening arrays eject the remaining two primary colors. A fourth ejection opening array is disposed between the first ejection opening array and the second or third ejection opening array.

Abstract: The present invention provides a liquid ejection head for which the peeling of an orifice plate from a substrate seldom occurs, even in a structure such that the walls that define each energy application chamber are narrowed toward an ejection port. The walls that define a first pressure chamber are inclined inward within the first pressure chamber, so that the first pressure chamber is narrowed, toward an ejection port, along a direction perpendicular to the heater formation face on which heaters are arranged. Further, the walls that define each ink flow path are inclined in the ink ejection direction. Furthermore, the angle at which the walls that define the ink flow path are inclined relative to the ink ejection direction is smaller than the angle at which the walls that define the first pressure chamber are inclined inward, within the first pressure chamber.

Abstract: An object of the present invention is to provide an ink jet print head having plural types of nozzles arranged on the same substrate and through which ink droplets of different sizes are ejected, the ink jet print head exhibiting acceptable ejection performance regardless of the type of the nozzle. Thus, according to the present invention, each of the plural types of nozzles includes a bubbling chamber having an ejection energy generating element allowing an ink droplet to be ejected to a position located opposite an ejection port and an ejection port portion allowing the ejection port and the bubbling chamber to communicate with each other. Ratio of opening area of the ejection port portion at a position where the ejection port portion and the bubbling chamber communicate with each other, to the opening area of the ejection port is higher for the nozzle with a smaller ejection amount.