Search

EP-4342677-B1 - INK JET RECORDING METHOD, INK JET RECORDING APPARATUS AND AQUEOUS INK

EP4342677B1EP 4342677 B1EP4342677 B1EP 4342677B1EP-4342677-B1

Inventors

  • KAWABE, MINAKO
  • ASAO, MASAYA

Dates

Publication Date
20260506
Application Date
20230919

Claims (19)

  1. An ink jet recording method including a recording step of ejecting an aqueous ink from a recording head (1200) to apply it to a recording medium to record an image, the ink jet recording method uses an ink jet recording apparatus equipped with an ink circulation flow path for circulating the aqueous ink from an ink storage portion (1503) to the recording head, comprising the ink storage portion for storing the aqueous ink, the recording head of an ink jet system for ejecting the aqueous ink, a cooling portion (1516) for cooling the aqueous ink, a heating portion (1517) for heating the aqueous ink, and a pump (1505) for circulating the aqueous ink, characterised in that the cooling portion, the pump, the heating portion and the recording head, those constitute the ink circulation flow path, are equipped in this order, the cooling portion is provided separately from the ink storage portion, the method includes a step for supplying the ink cooled in the cooling portion to the pump, and wherein the aqueous ink comprises a resin particle.
  2. The ink jet recording method according to claim 1, wherein a circulation flow rate of the aqueous ink in the ink circulation flow path is 250 mL/min or more to 700 mL/min or less.
  3. The ink jet recording method according to claim 1 or 2, wherein the aqueous ink is cooled to 15°C or more to 30°C or less in the cooling portion.
  4. The ink jet recording method according to any one of claims 1 to 3, wherein the cooling portion is a heat exchanger in which a liquid cooled by a chiller is circulated inside.
  5. The ink jet recording method according to any one of claims 1 to 4, wherein the aqueous ink is heated to 35°C or more to 55°C or less in the heating portion.
  6. The ink jet recording method according to any one of claims 1 to 5, wherein the heating portion is provided separately from the recording head.
  7. The ink jet recording method according to any one of claims 1 to 6, wherein an ejection system of the recording head is a system including causing film boiling in the aqueous ink with an electro-thermal converter to form air bubbles, to thereby eject the aqueous ink.
  8. The ink jet recording method according to any one of claims 1 to 7, wherein the recording head is a line head.
  9. The ink jet recording method according to any one of claims 1 to 8, wherein a glass transition temperature of the resin particle is 50°C or more to 90°C or less.
  10. The ink jet recording method according to any one of claims 1 to 9, wherein an anionic group amount of the resin particle is 70 µmol/g or more to 400 µmol/g or less.
  11. The ink jet recording method according to any one of claims 1 to 10, wherein the resin particle is formed of an acrylic resin.
  12. The ink jet recording method according to any one of claims 1 to 11, wherein the aqueous ink further comprises a wax particle.
  13. The ink jet recording method according to claim 12, wherein a melting temperature of the wax particle is 70°C or more to 130°C or less.
  14. The ink jet recording method according to claim 12, wherein a glass transition temperature of the resin particle is lower than a melting temperature of the wax particle.
  15. The ink jet recording method according to any one of claims 1 to 14, wherein the aqueous ink further comprises a coloring material.
  16. The ink jet recording method according to any one of claims 1 to 15, wherein the recording medium has a permeability of the aqueous ink.
  17. The ink jet recording method according to any one of claims 1 to 15, wherein the recording medium has no permeability of the aqueous ink.
  18. An ink jet recording apparatus comprises an ink circulation flow path for circulating an aqueous ink from an ink storage portion (1503) to a recording head (1200), comprising the ink storage portion for storing the aqueous ink, the recording head of an ink jet system for ejecting the aqueous ink, a cooling portion (1516) for cooling the aqueous ink, a heating portion (1517) for heating the aqueous ink, and a pump (1505) for circulating the aqueous ink, characterised in that the cooling portion (1516), the pump (1505), the heating portion (1517) and the recording head (1200), those constitute the ink circulation flow path, are equipped in this order, the cooling portion is provided separately from the ink storage portion, the apparatus includes means for supplying the ink cooled in the cooling portion to the pump, and wherein the aqueous ink comprises a resin particle.
  19. An aqueous ink to be used for the ink jet recording method according to any one of claims 1 to 17, wherein the aqueous ink comprises a resin particle, and a glass transition temperature of the resin particle is 50°C or more to 90°C or less.

Description

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an ink jet recording method, an ink jet recording apparatus and an aqueous ink. Description of the Related Art Recently, ink jet recording apparatuses are increasingly used in office printing and commercial printing fields. Further, in the ink jet recording apparatus, there is a need to further increase a recording speed as well as ability to record images with excellent robustness such as abrasion resistance. To maintain ink ejection stability at high level even when recording at a high speed, for example, there is a method to use ink that has been warmed to reduce its viscosity. There is also a method to configure an ink circulation flow path that circulates ink from the ink storage portion to the recording head in order to prevent the ink in the vicinity of an ejection orifice from becoming thicker due to evaporation of liquid components and causing non-ejection. For example, in order to record images in which white out is suppressed while improving ink ejection properties, an image forming method using an apparatus equipped with an ink circulation system that controls the temperature of the ink when it is filled in the recording head and when it is ejected from the recording head has been proposed (Japanese Patent Application Laid-Open No. 2014-065241). To improve the abrasion resistance of recorded images, for example, ink containing a resin particle can be used. For example, in order to record images with excellent abrasion resistance while circulating ink at a constant flow rate, an ink ejecting method using an ink ejection apparatus equipped with an ink circulation system that circulates ink containing a resin particle and in which viscosity rise during evaporation of liquid components is suppressed has been proposed (Japanese Patent Application Laid-Open No. 2018-043511). JP 2007 296640 discloses an inkjet recorder including a liquid storage tank and a liquid supply system, which can circulate a liquid within a liquid circulation course that returns to the liquid storage tank. SUMMARY OF THE INVENTION To record images with excellent abrasion resistance at high speed, the inventors studied a method for recording images by using an apparatus equipped with the ink circulation system and by circulating ink containing a resin particle into the ink circulation system as proposed in Japanese Patent Application Laid-Open No. 2014-065241 and Japanese Patent Application Laid-Open No. 2018-043511. As a result, it was found that when the ink is circulated for a long period of time, the ejection state gradually becomes unstable and the ejection stability of the ink tends to deteriorate. Accordingly, an object of the present invention is to provide an ink jet recording method that can record an image with good ink ejection stability and excellent abrasion resistance while circulating ink for a long period of time from the ink storage portion to the recording head. In addition, another object of the present invention is to provide an ink jet recording apparatus and an aqueous ink to be used in the ink jet recording method. According to the present invention, there is provided the ink jet recording method according to claim 1, the inkjet recording apparatus according to claim 18, and the aqueous ink according to claim 19. Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view for illustrating an ink jet recording apparatus according to one embodiment of the present invention.FIG. 2 is a perspective view for illustrating an example of a liquid applying device.FIG. 3 is a sectional perspective view for illustrating an example of an ejection element substrate.FIG. 4 is a schematic view for illustrating an example of a liquid supply system.FIG. 5 is a schematic view for illustrating another example of a heating portion.FIG. 6 is a schematic view for illustrating another example of a fixing portion. DESCRIPTION OF THE EMBODIMENTS The present invention is described in more detail below by way of exemplary embodiments. In the present invention, when a compound is a salt, the salt is present as dissociated ions in an ink, but the expression "contain a salt" is used for convenience. In addition, an aqueous ink and reaction liquid for ink jet are sometimes referred to simply as "ink" and "reaction liquid". Physical property values are values at normal temperature (25°C), unless otherwise stated. The descriptions "(meth)acrylic acid" and "(meth)acrylate" refer to "acrylic acid or methacrylic acid" and "acrylate or methacrylate", respectively. The inventors studied a method that can record an image with good ink ejection stability and excellent abrasion resistance while circulating ink for a long period of time in the circulation flow path from the ink storage portion to the recor