Inkjet recording method and inkjet recording device

Patent metadata

Field	Value
Publication number	US-9757942-B2
Application number	US-201514939266-A
Country	US
Kind code	B2
Filing date	Nov 12, 2015
Priority date	Nov 21, 2014
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

An inkjet recording method performed by inkjet recording device including nozzle plate with nozzle to eject droplets of ink; recording head including liquid chamber with which the nozzle is in communication, and pressure-generating unit configured to generate pressure in the liquid chamber; and signal-generating unit configured to generate signal applied to the pressure-generating unit, and allowing the droplets of the ink to eject by the pressure generated by the pressure-generating unit according to the signal, wherein the ink has static surface tension of 18.0 mN/m to 27.0 mN/m at 25° C., the ink has receding contact angle on the nozzle plate of less than 50°, the signal has two-step pull pulse for pulling the ink into the nozzle in two-step manner within one printing unit cycle, and the method includes pulling the ink located in proximity to nozzle outlet into the nozzle of the two-step pull pulse, to form meniscus at predetermined position.

First claim

What is claimed is:

1. An inkjet recording method, which is performed by an inkjet recording device comprising: a nozzle plate comprising a nozzle configured to eject droplets of an ink; a recording head comprising a liquid chamber with which the nozzle is in communication, and a pressure generating unit configured to generate pressure in the liquid chamber; and a signal generating unit configured to generate a signal to be applied to the pressure generating unit, and which allows the droplets of the ink to eject by the pressure which is generated by the pressure generating unit according to the signal,
wherein the ink has a static surface tension of 18.0 mN/m to 27.0 mN/m at 25° C.,
wherein the ink has a receding contact angle on the nozzle plate of less than 50°,
wherein the signal has a two-step pull pulse for pulling the ink into the nozzle in a two-step manner within one printing unit cycle, and
wherein the inkjet recording method comprises pulling the ink located in proximity to a nozzle outlet into the nozzle by the two-step pull pulse, to thereby form a meniscus at a predetermined position.

2. The inkjet recording method according to claim 1 , wherein, in the signal within one printing unit cycle, the pull pulse is present prior to an ejection pulse for ejecting the ink.

3. The inkjet recording method according to claim 1 , wherein a surface of the nozzle plate comprises a water-repellent film.

4. The inkjet recording method according to claim 1 , wherein the ink is an ink set comprising a black ink and one or more other color inks,
wherein each ink in the ink set has the static surface tension of 18.0 mN/m to 27.0 mN/m at 25° C.,
wherein each ink in the ink set has the receding contact angle on the nozzle plate of less than 50°, and
wherein a difference in the static surface tension between the black ink and other color ink or each of other color inks (black ink—other color ink or each of other color inks) is 0 mN/m to 4 mN/m at 25° C.

5. The inkjet recording method according to claim 1 , wherein the ink comprises water, a colorant, a surfactant, and a water-soluble organic solvent.

6. The inkjet recording method according to claim 1 , wherein the ink has a viscosity of 3 mPa·s to 20 mPa·s at 25° C.

7. An ink recorded matter, comprising:
a recording medium; and
an image on the recording medium,
wherein the image is formed by the inkjet recording method according to claim 1 .

8. An inkjet recording device, comprising:
a nozzle plate comprising a nozzle configured to eject droplets of an ink;
a recording head comprising a liquid chamber with which the nozzle is in communication, and a pressure generating unit configured to generate pressure in the liquid chamber; and
a signal generating unit configured to generate a signal to be applied to the pressure generating unit,
wherein the inkjet recording device allows the droplets of the ink to eject by the pressure which is generated by the pressure generating unit according to the signal,
wherein the ink has a static surface tension of 18.0 mN/m to 27.0 mN/m at 25° C.,
wherein the ink has a receding contact angle on the nozzle plate of less than 50°,
wherein the signal has a two-step pull pulse for pulling the ink into the nozzle in a two-step manner within one printing unit cycle, and
wherein the inkjet recording device comprises a unit configured to allow the ink located in proximity to a nozzle outlet to be pulled into the nozzle by the two-step pull pulse, to thereby form a meniscus at a predetermined position.

9. The inkjet recording device according to claim 8 , wherein, in the signal within one printing unit cycle, the pull pulse is present prior to an ejection pulse for ejecting the ink.

10. The inkjet recording device according to claim 8 , wherein a surface of the nozzle plate comprises a water-repellent film.

11. The inkjet recording device according to claim 8 , wherein the ink is an ink set comprising a black ink and one or more other color inks,
wherein each ink in the ink set has the static surface tension of 18.0 mN/m to 27.0 mN/m at 25° C.,
wherein each ink in the ink set has the receding contact angle on the nozzle plate of less than 50°, and
wherein a difference in the static surface tension between the black ink and other color ink or each of other color inks (black ink—other color ink or each of other color inks) is 0 mN/m to 4 mN/m at 25° C.

12. The inkjet recording device according to claim 8 , wherein the ink comprises water, a colorant, a surfactant, and a water-soluble organic solvent.

13. The inkjet recording device according to claim 8 , wherein the ink has a viscosity of 3 mPa·s to 20 mPa·s at 25° C.

Assignees

• Masuda Kiminori
• Bannai Akiko
• Tamai Takashi
• Kitaoka Naoko
• Akiyama Kohta
• Ricoh Co Ltd

Inventors

• Masuda Kiminori
• Bannai Akiko
• Tamai Takashi
• Kitaoka Naoko
• Akiyama Kohta

Classifications

• B41J2/2107

  characterised by the ink properties (supplying ink in a solid state B41J2/17593) · CPC title

• B41J2/04588 Primary

  using a specific waveform · CPC title

• B41J2/04581

  controlling heads based on piezoelectric elements · CPC title

• B41J2/04573

  Timing; Delays · CPC title