Abstract: A base member for an ink jet head in which a heat accumulation layer, a heat generating member generating heat energy used to discharge ink, and protection film for protecting the heat generating member are formed in succession on a substrate, characterized in that the heat resistance value of a portion of the heat accumulation layer which is under the heat generating member is two times or greater and less than five times as great as the heat resistance value of a portion of the protection film which is on the heat generating member.

Abstract: An ink jet recording head is provided with one heat generating member in each of ink flow paths, and the discharge port thereof is arranged on the extended line extending in the normal direction from the center of the main surface of the heat generating member to the surface of the substrate. Then, on the surface of the substrate, non-bubbling area is provided on the center within the projected area having the discharge port projected thereon. Bubble brought to the boil by the heat generating member pushes out ink from the discharge port by the pressure exerted by the bubble, while being communicated with the outside. With the structure thus arranged, it is made possible to enhance the precision of discharge direction of the liquid droplet discharged from the discharge port.

Abstract: An ink jet recording head is provided with one heat generating member in each of ink flow paths, and the discharge port thereof is arranged on the extended line extending in the normal direction from the center of the main surface of the heat generating member to the surface of the substrate. Then, on the surface of the substrate, non-bubbling area is provided on the center within the projected area having the discharge port projected thereon. Bubble brought to the boil by the heat generating member pushes out ink from the discharge port by the pressure exerted by the bubble, while being communicated with the outside. With the structure thus arranged, it is made possible to enhance the precision of discharge direction of the liquid droplet discharged from the discharge port.

Abstract: An ink jet head base body in which a heat accumulation layer, a heater generating heat energy used for discharging ink, and a protection film protecting the heater are sequentially formed on a substrate. The ink jet head base body is characterized in that a total thickness of a portion above from the heater in the protection film ranges from 0.2 ?m to 0.6 ?m, a heat resistance value of the portion above from the heater in the protection film ranges from 5×10?9 m2·K/W to 50×10?9 m2·K/W, and the heat resistance value of a portion below from the heater in the heat accumulation layer is not lower than double the heat resistance value of the portion above from the heater in the protection film.

Abstract: An ink jet head according to the present invention includes multiple discharge ports for discharging ink, multiple ink flow paths for communicating with the discharge ports, and heat generating elements for generating bubbles in ink filling the ink flow paths. For each ink flow path, two heat generating elements are arranged therein, and the discharge port is arranged along a line that is extended, from the center of a pressure generation region formed by the two heat generating elements, in the normal direction relative to the surface of the substrate. The arrangement pitch of the heat generating elements is equal to or greater than 600 dpi, and the interval dhn between a partition wall defining an ink flow path and the heat generating element adjacent to the partition wall is equal to or smaller than 4 ?m.

Abstract: The present invention provides an ink jet recording head which, when a smaller liquid droplet is obtained, can suppress or reduce stagnation of liquid in a second discharge port portion, prevent an offset meniscus in a discharge port, reduce unstable satellite(s) and realize stable discharging with less image deterioration and less floating mist. In the present invention, two heaters 1a and 1b are provided for each bubble generating chamber and the heaters 1a and 1b are arranged substantially symmetrically with respect to a center or a center of gravity of a second discharge port portion. In a plan view viewed from a direction perpendicular to a main surface of an element substrate, at least one of two heaters is positioned to straddle an inner area of the second discharge port portion and an outer area out of the second discharge port portion.

Abstract: An ink jet recording head is provided with one heat generating member in each of ink flow paths, and the discharge port thereof is arranged on the extended line extending in the normal direction from the center of the main surface of the heat generating member to the surface of the substrate. Then, on the surface of the substrate, non-bubbling area is provided on the center within the projected area having the discharge port projected thereon. Bubble brought to the boil by the heat generating member pushes out ink from the discharge port by the pressure exerted by the bubble, while being communicated with the outside. With the structure thus arranged, it is made possible to enhance the precision of discharge direction of the liquid droplet discharged from the discharge port.

Abstract: An ink jet recording head is provided with one heat generating member in each of ink flow paths, and the discharge port thereof is arranged on the extended line extending in the normal direction from the center of the main surface of the heat generating member to the surface of the substrate. Then, on the surface of the substrate, non-bubbling area is provided on the center within the projected area having the discharge port projected thereon. Bubble brought to the boil by the heat generating member pushes out ink from the discharge port by the pressure exerted by the bubble, while being communicated with the outside. With the structure thus arranged, it is made possible to enhance the precision of discharge direction of the liquid droplet discharged from the discharge port.

Abstract: An ink jet head includes a substrate provided with heat generating members for generating a bubble in ink on a surface of the substrate, a plurality of discharge ports for discharging the ink, the ports opposed to the surface of the substrate, and a plurality of ink flow passages communicating with the plurality of discharge ports to feed the ink. A plurality of the heat generating members is provided in each of the ink flow passages, and the discharge port is arranged on an extension line extending from a center of a pressure generating area composed of the plurality of heat generating members toward the surface of the substrate in a normal direction. Moreover, a distance dhc between centers of each of two heat generating members arranged most apart from each other among the plurality of heat generating members is set to be larger than a diameter do of an aperture of the discharge port.

Abstract: Since the large amount nozzle arrays are disposed at first columns and the small amount nozzle arrays are disposed at second columns on both sides of the shifting directions along the main scan direction, the deflection of the ink droplet caused by the first air flows is totally reduced.

Abstract: A liquid discharge head substrate has improved protection performance of protective films for protecting heaters while effective bubble-forming regions are being secured. The protective films for protecting a plurality of heating elements provided on a substrate are formed using a platinum group element and are separately provided for the respective heating elements.

Abstract: An ink jet head base body in which a heat accumulation layer, a heater generating heat energy used for discharging ink, and a protection film protecting the heater are sequentially formed on a substrate. The ink jet head base body is characterized in that a total thickness of a portion above from the heater in the protection film ranges from 0.2 ?m to 0.6 ?m, a heat resistance value of the portion above from the heater in the protection film ranges from 5×10?9 m2·K/W to 50×10?9 m2·K/W, and the heat resistance value of a portion below from the heater in the heat accumulation layer is not lower than double the heat resistance value of the portion above from the heater in the protection film.

Abstract: A base member for an ink jet head in which a heat accumulation layer, a heat generating member generating heat energy used to discharge ink, and protection film for protecting the heat generating member are formed in succession on a substrate, characterized in that the heat resistance value of a portion of the heat accumulation layer which is under the heat generating member is two times or greater and less than five times as great as the heat resistance value of a portion of the protection film which is on the heat generating member.

Abstract: This invention provides an image printing apparatus in which, when the printhead temperature rises in driving the printhead at a high speed, the ink discharge amount is optimized in accordance with the temperature rise to achieve high-quality, high-efficiency printing. For this purpose, in an image printing system using a time division simultaneous driving method of grouping a predetermined number of printing elements into a plurality of blocks every predetermined number of printing elements and driving printing elements belonging to the same block at the same driving timing, if the printhead falls within a predetermined temperature range, droplets are discharged using all blocks to print an image. To the contrary, if the printhead reaches the predetermined temperature or higher, blocks to be used are restricted in accordance with the printhead temperature, the total number of droplets is decreased, and the amount of one droplet is increased to print an image.

Abstract: In an ink jet recording head from which a small ink droplet and a large ink droplet can be discharged, a common liquid chamber is connected to discharge ports via ink flow paths and pressure chambers, and ink droplets are discharged from the discharge ports by utilizing thermal energy of heaters. Widths of the ink flow paths are narrower than widths of the pressure chambers so that the ink flow paths act as restriction portions. If it is assumed that a sectional area of the small liquid droplet ink flow path is SS, a sectional area of the small liquid droplet pressure chamber is SRS, a sectional area of the large liquid droplet ink flow path is SL and a sectional area of the large liquid droplet pressure chamber is SRL, a relationship SS/SRS<SL/SRL is established.

Abstract: This invention provides an image printing apparatus in which, when the printhead temperature rises in driving the printhead at a high speed, the ink discharge amount is optimized in accordance with the temperature rise to achieve high-quality, high-efficiency printing. For this purpose, in an image printing system using a time division simultaneous driving method of grouping a predetermined printing elements into a plurality of blocks every predetermined number of printing elements and driving printing elements belonging to the same block at the same driving timing, if the printhead falls within a predetermined temperature range, droplets are discharged using all blocks to print an image. To the contrary, if the printhead reaches the predetermined temperature or higher, blocks to be used are restricted in accordance with the printhead temperature, the total number of droplets is decreased, and the amount of one droplet is increased to print an image.

Abstract: Since the large amount nozzle arrays are disposed at first columns and the small amount nozzle arrays are disposed at second columns on both sides of the shifting directions along the main scan direction, the deflection of the ink droplet caused by the first air flows is totally reduced.

Abstract: An ink jet head includes a substrate provided with heat generating members for generating a bubble in ink on a surface of the substrate, a plurality of discharge ports for discharging the ink, the ports opposed to the surface of the substrate, and a plurality of ink flow passages communicating with the plurality of discharge ports to feed the ink. A plurality of the heat generating members is provided in each of the ink flow passages, and the discharge port is arranged on an extension line extending from a center of a pressure generating area composed of the plurality of heat generating members toward the surface of the substrate in a normal direction. Moreover, a distance dhc between centers of each of two heat generating members arranged most apart from each other among the plurality of heat generating members is set to be larger than a diameter do of an aperture of the discharge port.

Abstract: An ink jet recording head is provided with one heat generating member in each of ink flow paths, and the discharge port thereof is arranged on the extended line extending in the normal direction from the center of the main surface of the heat generating member to the surface of the substrate. Then, on the surface of the substrate, non-bubbling area is provided on the center within the projected area having the discharge port projected thereon. Bubble brought to the boil by the heat generating member pushes out ink from the discharge port by the pressure exerted by the bubble, while being communicated with the outside. With the structure thus arranged, it is made possible to enhance the precision of discharge direction of the liquid droplet discharged from the discharge port.

Abstract: When a plurality of heaters in the printing head are driven and the pulse width is controlled according to a change in the voltage drop corresponding to the number of driven heaters, the control range of the pulse width is properly determined to ensure a stable ink ejection. More specifically, the driving bit number for each block representing the number of heaters to be driven is counted; and based on this count value, a table is referenced to determine the pulse width of a single pulse. Then, in an inappropriate range of pulse width where the ink ejection amount varies largely, the single pulse is changed into a double pulse by referencing the table with the pulse width to obtain a double pulse driving waveform.