JP2007331151A - Inkjet recording method and inkjet recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording method which provides fixing properties or fastness properties to a formed image and additionally prevents a nozzle from clogging caused by a reaction of both ink mists near a print head in the inkjet recording method combining a recording ink and a reacting ink, and to provide a recording apparatus. <P>SOLUTION: The inkjet recording method provides the recording ink 80 from one face of a sheet-like recording medium 70 and the reacting ink 90 from the other face and reacts these inks in a recording medium to form the image. In addition, the inkjet recording apparatus is arranged so that a print head 10 delivering the recording ink and a print head 50 delivering the reacting ink are opposed by placing the sheet-like recording medium held by a holding means between them, and the recording ink provided on one face and the reacting ink provided on the other face can react with each other in the recording medium. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ink jet recording method and a recording apparatus, and more particularly to an ink jet recording method and a recording apparatus capable of obtaining high-quality printing and high-quality color images on plain paper.

  The ink jet recording method is a printing method in which printing is performed by causing a droplet of an ink composition to fly and adhere to a recording medium such as paper. Inks used in ordinary ink jet recording generally contain water as a main component, and inks containing a water-soluble high-boiling solvent such as glycol are generally used for the purpose of preventing drying and clogging.

  When recording on plain paper using such ink, the ink penetrates into the inside of the recording paper and a sufficient image density is not obtained, or the filler and sizing agent on the surface of the recording paper are not uniform. There is a problem such as non-uniformity in image density, which is considered to be due to various distributions. In particular, when a color image is obtained, the inks of a plurality of colors are stacked one after another before fixing, so that the color is blurred or mixed unevenly at the boundary portion of the different color image (hereinafter referred to as “color image”). In some cases, satisfactory images could not be obtained.

As means for solving the above-described problem, a method is disclosed in which a liquid for improving an image is deposited on recording paper prior to jetting of recording ink. JP-A-63-29971 discloses a method of recording an ink containing an anionic dye after adhering a liquid containing an organic compound having two or more cationic groups per molecule. Japanese Patent Application Laid-Open No. 64-9279 discloses a method for recording ink after depositing an acidic liquid containing succinic acid or the like. Japanese Patent Application Laid-Open No. 64-63185 discloses a method for adhering a liquid for insolubilizing a dye before recording. In addition, an ink jet recording method for printing two liquids has been proposed (see Japanese Patent Laid-Open Nos. 3-240557 and 3-240558).
JP 63-29971 A JP-A 64-9279 JP-A 64-63185 JP-A-3-240557 JP-A-3-240558

  However, in any of the above cases, since the reaction is completed only on one side of the recording medium, the color material of the reacted ink stays only on the surface side of the recording medium. In some cases, it was weak in marker properties.

  In addition, there is a case where a reaction occurs in the vicinity of the print head nozzles due to floating droplets (mist) generated when ink is ejected onto the recording medium, and nozzle clogging is likely to occur.

  SUMMARY OF THE INVENTION An object of the present invention is a recording ink jet method for applying a liquid for imparting fixability or fastness to an image separately from a recording ink, and an ink jet recording method which is excellent in resistance to spot and marker, and hardly causes nozzle clogging. And providing a recording apparatus.

  The first aspect of the present invention as a means for solving the above problems is a sheet-like recording medium comprising a combination of a recording ink and a reactive ink for imparting at least one of fixing property and fastness to an image. In an inkjet recording method in which an image is formed by application by an inkjet method, the recording ink is applied from one side of the sheet-like recording medium, the reactive ink is applied from the other side, and the ink is added to the recording medium. An ink jet recording method comprising reacting in a recording medium.

  Furthermore, a second aspect of the present invention provides a sheet-like recording medium holding means in an ink jet recording apparatus using a combination of a recording ink and a reactive ink for imparting at least one of fixing property and fastness to an image. A first print head that discharges recording ink and a second print head that discharges reactive ink, and the first print head and the second print head are held by the holding means. The recording ink discharged from the first print head on one surface of the sheet-like recording medium and the other surface of the sheet-like recording medium are opposed to each other. An ink jet recording apparatus, characterized in that the reaction ink ejected from the second print head is disposed at a position that allows reaction in the sheet-like recording medium. .

  As an effect of the present invention, since the reaction between the recording ink and the reactive ink occurs in the middle layer of the recording medium, a drastic improvement in the resistance to resistance and marker is expected compared to the conventional system in which the reaction is completed only on one side of the recording medium. it can. Further, since the print heads are cut off by the recording medium during printing, the mist generated by both print heads does not meet each other. Therefore, no reaction occurs in the vicinity of the print head nozzle, and nozzle clogging can be prevented.

  In the inkjet recording method according to the present invention, a recording ink and a reactive ink are combined and applied to a sheet-like recording medium by an inkjet method to form an image. At that time, recording ink is applied from one side of the sheet-like recording medium, reactive ink is applied from the other side, and these inks are reacted in the recording medium.

  The sheet-like recording medium in the present invention is an ink-absorbing recording medium that can permeate the recording ink that lands on one surface and the reaction ink that lands on the other surface and reacts in the recording medium. If there is, it can be used without any particular limitation. For example, ordinary plain paper used in the ink jet method can be suitably used. Also, the form of the sheet is not particularly limited. For example, in the case of plain paper, a cut sheet that is cut into a standard shape such as A4, or a sheet that is cut into a predetermined shape after recording with a sheet drawn from a roll is preferable. Available to:

  As the recording ink in the present invention, an ink composition containing a coloring material, and any ink composition used in an ink jet method can be used, but an aqueous dye ink or aqueous pigment having permeability to a recording medium. Ink can be suitably used.

  The reactive ink in the present invention is a liquid composition containing a component that reacts with a color material contained in a recording ink to give desired characteristics. As a component contained in such a liquid composition, for example, a component for insolubilizing or aggregating a coloring material and fixing it in a recording medium, or a weather resistance such as light resistance and oxygen resistance for an image formed by reaction with a coloring material. The component which provides property is mentioned.

  In the method of the present invention, a plurality of types of recording inks can be used, and a plurality of types of reactive inks can be used in combination with these.

  The order of ink application to the sheet-shaped recording medium is that the recording ink is landed after the landing of the reactive ink, the reactive ink is landed after the landing of the recording ink, or the reactive ink and the recording ink are simultaneously applied. You may make it land. This order and the time difference to be applied take into consideration the penetrability of the recording ink and the reactive ink into the sheet-like recording medium, the nature of the reaction between the recording ink and the reactive ink, and the desired fixing position of the ink in the recording medium. And can be adjusted as appropriate.

The ink jet recording apparatus according to the present invention includes at least a sheet-shaped recording medium holding unit, a first print head that discharges recording ink, and a second print head that discharges reactive ink. The first and second print heads are arranged to face each other with the sheet-like recording medium held by the holding unit interposed therebetween. Here, the opposing positions of the first and second print heads are the reaction in the sheet-like recording medium between the recording ink ejected on one side of the sheet-like recording medium and the reaction ink ejected on the other side. If possible, it can be arranged by being translated from a position facing directly in front (completely facing). As the print head used for ejecting the reactive ink, the same print head as that used for the recording ink may be used, or another print head may be used. A plurality of print heads may be arranged as the first and second print heads.
As the holding means, instead of a conventional platen, a rib that automatically protrudes into the hole space only when the paper discharge roller enters and when the LF roller kicks may be disposed.

  The ink jet recording apparatus may further include a moving unit that moves the sheet-like recording medium relative to the print heads between the print heads arranged to face each other. In the apparatus having this configuration, the moving means moves between the first print head that discharges the recording ink and the second print head that discharges the reactive ink. The recording ink and the reaction ink can be applied to the sheet recording medium by relatively moving the sheet recording medium.

Example 1
Embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view of an ink jet recording apparatus according to a first embodiment of the present invention.

  As shown in FIG. 1, an ink jet head (for recording ink) 10 and an ink jet head (for reactive ink) 50 are arranged while being supported by carriages 30 and 60 at positions facing each other with a recording medium 70 interposed therebetween. Yes. The carriages 30 and 60 are supported by the shaft 40 so as to be movable in the front and back direction in the figure. That is, the device configuration is shown as a cross-sectional view in a plane orthogonal to the axial direction of the shaft 40.

  In FIG. 1, the ink jet head (for recording ink) 10 and the ink jet head (for reactive ink) 50 are not strictly positioned opposite to each other. This is because consideration has been given so that the ink does not accidentally land on each nozzle due to a conveyance failure of the recording medium 70, and the reaction does not occur. As long as countermeasures against poor conveyance of the recording medium 70 are taken, the ink jet head (for recording ink) 10 and the ink jet head (for reactive ink) 50 may be disposed at completely opposed positions.

  Next, the details of the inkjet head 10 (same for 50) are shown in FIG.

  As shown in FIG. 2, the inkjet head 10 that is a means for ejecting liquid is supported by a carriage 30. The inkjet head 10 is formed with a plurality of nozzle rows 20 each having a plurality of ink ejection openings. A shaft 40 is passed through the carriage 30, and the carriage 30 is capable of reciprocating on the shaft 40 by power transmission means (not shown).

  On the other hand, the nozzle row 20 is formed by a plurality of liquid discharge ports 15. An energy element for generating energy for discharging the liquid is provided inside the liquid discharge port 15. For example, in the case of a thermal ink jet method in which a liquid is heated and the liquid is ejected with generated bubbles, a heater for liquid heating, or in the case of a piezo ink jet method in which the liquid itself is subjected to a volume change and thereby the liquid is ejected. Each of the piezoelectric elements is formed.

  In FIG. 1, first, a reactive ink droplet 90 is landed on a recording medium 70 from an inkjet head (for reactive ink) 50. Subsequently, the recording ink droplet 80 is opposite to the surface of the recording medium 70 on which the reactive ink droplet 90 has landed from the inkjet head (for recording ink) 10 disposed opposite to the inkjet head (for reactive ink) 50. It is landed on the surface. The reactive ink droplet 90 and the recording ink droplet 80 penetrate into the recording medium from the opposite surfaces of the recording medium toward the recording medium middle layer. Eventually, the two ink droplets meet and react in the middle layer of the recording medium to become the reacting ink 95, and finally the reacted ink 100.

  The reacted ink 100 generated in this way is formed in the middle layer of the recording medium. Therefore, the ink resistance and marker resistance, as well as the water resistance and weather resistance, compared to the conventional ink that has reacted only on one side of the recording medium. It shows very good characteristics.

  The image density can be adjusted by controlling the permeability of the reactive ink droplet 90 and the recording ink droplet 80 to shake the formation layer of the reacted ink 100 toward the recording ink.

  Since the heads of each other are blocked by the recording medium at the time of printing, the mist generated by both heads does not meet each other. Therefore, no reaction occurs in the vicinity of the print head nozzle, and nozzle clogging can be prevented.

  Note that the scanning direction of the inkjet head (for recording ink) 10 and the scanning direction of the inkjet head (for reactive ink) 50 may be the same or relative directions. In the case of the relative direction as in the present embodiment, the inertial force is canceled and the effect of suppressing the vibration of the printer main body can be expected.

It is sectional drawing of the inkjet recording device of this invention. It is a bird's-eye view which shows the detail of the inkjet head used by this invention.

Explanation of symbols

10 Inkjet head (for recording ink)
15 Liquid discharge port 20 Nozzle array 30 Carriage 40 Shaft 50 Inkjet head (for reactive ink)
60 Carriage 70 Recording medium 80 Recording ink drop 90 Reactive ink drop 95 In-reaction ink 100 Reacted ink

Claims (4)

In an ink jet recording method for forming an image by combining a recording ink for imparting at least one of fixability and fastness to an image and a reactive ink and applying the ink to a sheet-like recording medium by an ink jet method,
An ink jet recording method comprising applying the recording ink from one surface of the sheet-like recording medium, applying the reactive ink from the other surface, and reacting these inks in the recording medium.   The sheet-like recording medium is moved relative to these print heads between a print head that discharges recording ink and a print head that discharges reactive ink, which are arranged to face each other, and The inkjet recording method according to claim 1, wherein the recording ink and the reactive ink are applied to the sheet-shaped recording medium. In an inkjet recording apparatus using a combination of a recording ink and a reactive ink for imparting at least one of fixability and fastness to an image,
A sheet-like recording medium holding means, a first print head for discharging recording ink, and a second print head for discharging reactive ink,
The first print head and the second print head are opposed to each other with the sheet-like recording medium held by the holding means sandwiched between the first print head and one surface of the sheet-like recording medium. The recording ink discharged and the reaction ink discharged from the second print head on the other surface of the sheet-like recording medium are arranged at a position enabling reaction in the sheet-like recording medium. An ink jet recording apparatus.   The ink jet recording apparatus according to claim 3, further comprising a moving unit that moves the sheet-like recording medium relative to the print heads arranged to face each other with respect to the print heads.

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