US Patent 7806517 Liquid-jet recording head

An ink-jet recording head has two kinds of nozzles discharging different volumes of ink-drops. Large nozzles discharging larger ink-drops and small nozzles discharging smaller ink-drops are disposed alternately along a side of a common liquid chamber. The opening area of the large nozzles is larger than that of the small nozzles. Flow paths communicating with the small nozzles are shorter than those communicating with the large nozzles. Since the smaller ink-drops are discharged at higher frequency than the larger ink-drops, printing speed in high-quality recording using mainly the smaller ink-drops is improved.