Konica Minolta, Inc.

Kenji Mawatari

Ryohei Kobayashi

Masanori Shimazoe

The present invention discharges ink from a plurality of inkjet heads and is used when performing drive whereby one droplet or a plurality of droplets are discharged onto and united on one pixel. A drive signal includes a drive waveform comprising N number (N being an integer of at least 2) of drive waveform elements and is configured so as to fulfil the relationship 1.1 Tc&#x2264;Ts&#x2264;1.4 Tc, when Tc is the natural vibration cycle determined from the inkjet head structure and Ts is the time from the start point of the drive waveform to the start point of the subsequent drive waveform. As a result, velocity deviation caused by the resonant frequency of a piezoelectric actuator driving the inkjet head can be suppressed when driving an inkjet head using multiple gradations.

Inkjet recording device and inkjet head drive method

There is provided an ink jet recording apparatus including an ink jet head and a drive circuit. The ink jet head forms an image on a recording medium in response to a drive signal applied to multiple piezoelectric elements. The drive signal causes multiple pressure chambers corresponding to the multiple piezoelectric elements to expand or to contract in volume and causes ink in the multiple pressure chambers to be discharged from multiple nozzles. The drive circuit generates a drive signal for discharging multiple liquid droplets to one pixel for combining the multiple liquid droplets together and applies the drive signal to each of the multiple piezoelectric elements of the ink jet head. The drive signal includes multiple discharge pulses which make velocities of tips of respective liquid columns substantially same after a predetermined time from starting of ink discharge from the nozzles.

Ink jet recording apparatus and ink jet recording method

An inkjet head configured to eject inkjet ink includes a piezoelectric layer of a thin film and a diaphragm. An absolute value of a product of a piezoelectric constant dof the piezoelectric layer and a Young's modulus of the piezoelectric layer is 10 [C/m] to 15 [C/m]. Even when the inkjet head ejects ink having a high viscosity, variation of driving voltage during ejection can be suppressed.

Inkjet head and method of manufacturing the same, and inkjet recording apparatus

A piezoelectric thin film is formed by adding a donor element to lead zirconate titanate. In the piezoelectric thin film, a molar ratio of lead to a total sum of zirconium and titanium is 105% or higher, and, when positive and negative coercive electric fields in polarization and electric field hysteresis are referred to as Ec (+) and Ec (&#x2212;), respectively, a value of |Ec (+) |/|Ec (&#x2212;) | is 0.5 or more and 1.5 or less.

Piezoelectric thin film, piezoelectric actuator, inkjet head, inkjet printer, and method for manufacturing piezoelectric actuator

In order to obtain a ferroelectric thin film that is formed to have a predetermined thickness on a substrate, that have satisfactory crystallization and that achieves a high piezoelectric property, a method of manufacturing such a ferroelectric thin film and a method of manufacturing a piezoelectric element having such a ferroelectric thin film, when a dielectric material of a perovskite structure is formed into a film on the substrate, a predetermined amount of additive is mixed with PZT, and the concentration of the additive mixed is varied in the thickness direction of the thin film.

Ferroelectric thin film, method of manufacturing same and method of manufacturing piezoelectric element

A drive signal applied to a thin-film piezoelectric element includes the following: at least one discharge pulse that causes a drop of ink to be discharged from a pressure chamber; and a cancellation pulse. Said cancellation pulse has the same polarity as the discharge pulse(s) and serves to suppress reverberations of a pressure wave applied to the pressure chamber when the thin-film piezoelectric element is driven by the application of the discharge pulse(s). Letting Tc represent half of the natural vibration period of the pressure chamber, within the period within which a single pixel is placed, the cancellation pulse is applied once an amount of time equal to Tc times an even integer greater than or equal to 4 has passed since the end of the application of the first discharge pulse.

Inkjet head, method for driving same, and inkjet printer

A piezoelectric thin film which is of a perovskite type having a tetragonal crystal structure, the tetragonal crystal having a degree of (100) orientation of 80% or higher. The piezoelectric thin film is constituted of a lead lanthanum zirconate titanate (PLZT) which is a lead zirconate titanate (PZT) in which some of the lead has been replaced with lanthanum.

Piezoelectric thin film, piezoelectric element, ink-jet head, and ink-jet printer

A piezoelectric element having an electrode, a seed layer for controlling the crystal orientation of a piezoelectric layer, and the piezoelectric layer stacked in this order from the substrate side. The seed layer is composed of two or more layers stacked together each comprising crystals of spherical particles.

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Musashino, Japan

Kenji Mawatari