A liquid ejection head includes an ejection hole surface where a plurality of nozzles ejecting liquid open. The ejection hole surface includes a nozzle arrangement region where the plurality of nozzles are arranged. Each nozzle includes an inversely tapered part where a cross-sectional area increases toward the ejection hole surface. A first nozzle is arranged at a center part of a predetermined direction of the nozzle arrangement region, while second nozzles are arranged at the end parts at the two sides in the predetermined direction. When viewed from the ejection hole surface side as T, the width of the first nozzle's inversely tapered part is larger than the widths of the inversely tapered parts of the second nozzles. In the nozzle arrangement region, the ejection hole surface includes a shape that the center part in the predetermined direction projects with respect to the end parts on the two sides.

In an example implementation, a method of dual and single drop weight printing includes operating a printing system in a hybrid drop weight print mode to enable ejecting black ink from high drop weight nozzles and low drop weight nozzles, and ejecting color ink from high drop weight nozzles but not from low drop weight nozzles.

In a liquid discharge head, a third discharge port array group C1 which discharges a liquid of cyan, a second discharge port array group M1 which discharges a liquid of magenta, a fourth discharge port array group G which discharges a liquid of gray, a first discharge port array group Y which discharges a liquid of yellow, a second discharge port array group M2 which discharges a liquid of magenta, a third discharge port array group C2 which discharges a liquid of cyan are arranged in this order, in a direction. Each of discharge port arrays of the fourth discharge port array group G is formed of a plurality of discharge ports having a diameter smaller than that of a plurality of discharge ports which constitute first discharge port arrays of the second and third discharge port array groups C1, C2, M1 and M2.

A discharge port array unit including discharge ports having a small discharge port diameter is not arranged in a position adjacent to a discharge port array unit generating a strong airflow, and a discharge port array unit including discharge port array having not a small discharge port diameter is arranged in the position adjacent to the discharge port array unit generating a strong airflow.

A fluidic die may include a number of actuators. The number of actuators form a number of primitives. The fluidic die may include a digital-to-analog converter (DAC) to drive a number of the delay circuits. The delay circuits delay a number of activation pulses that activate the actuators associated with the primitives to reduce peak power demands of the fluidic die. A number of delay circuits may be coupled to each primitive.

Disclosed are an ink-jet printing head, an ink-jet printing method using the ink-jet printing head and an ink-jet printing device including the ink-jet printing head. The ink-jet printing head includes a chamber for accommodating ink and nozzle sets provided on a sidewall of the chamber where ink is sprayed. The nozzle sets are used for ink-jet printing on pixels at different positions, respectively. Each of nozzle sets includes sub-nozzles and the sub-nozzles in each nozzle set can spray different volumes of ink. In the printing head, by providing sub-nozzles having different ink spraying volumes in each nozzle set, ink droplets having desirable volumes can be sprayed from nozzle sets such that total volumes of ink droplets sprayed at different positions from nozzle sets could be more accurate. Therefore, a thickness of a film layer formed by ink-jet printing can be flexibly controlled and adjusted, while having a significantly improved accuracy.

Driving orders of driving blocks are controlled with regard to each of multiple types of ink so that landing positions of ink from the driving blocks differ in multiple scans, and in the mask patterns used, there is a relatively small number of superimposed pixels among pixels regarding which a large number of discharge permitted has been stipulated regarding a mask pattern corresponding to one type of ink and one scan and pixels regarding which a large number of discharge permitted has been stipulated regarding a mask pattern corresponding to another type of ink and the one scan.

An inkjet recording apparatus includes a recording head including a first discharge port configured to discharge a first amount of ink droplets and a second discharge port configured to discharge a second amount of ink droplets smaller than the first amount, a cap, a suction unit, and a determination unit configured to determine whether to perform a first recording operation by using the first and second discharge ports or a second recording operation by only using the first discharge port. If the first recording operation is determined to be performed, the suction unit performs a first suction operation with a first strength and a second suction operation with a second strength higher than the first strength. If the second recording operation is determined to be performed, the suction unit is controlled not to perform the second suction operation and to perform the first suction operation.

A discharge port array unit including discharge ports having a small discharge port diameter is not arranged in a position adjacent to a discharge port array unit generating a strong airflow, and a discharge port array unit including discharge port array having not a small discharge port diameter is arranged in the position adjacent to the discharge port array unit generating a strong airflow.

In a printing apparatus, a carriage is reciprocally movable in first and second directions. A control device is configured to perform executing one of first and second printing operations in accordance with an operation mode. The first printing operation prints a first image over a first range in a third direction crossing the first and second directions by ejecting ink from both first and second heads during one movement of the carriage in the first and second directions. The second printing operation prints a second image over a second range narrower than the first range in the third direction by ejecting ink from both the first and second heads during the one movement of the carriage. Ink ejection contribution during the one movement of the carriage is shared by the first and second heads at a prescribed contribution ratio in the second printing operation.