JP4846326B2 - Inkjet recording method - Google Patents

Description

  The present invention relates to an ink jet recording method, and more particularly, to an ink jet recording method suitable for curing and forming a high quality image using multiple liquids.

  An ink jet system that discharges ink from an ink discharge port such as a nozzle is small and inexpensive, and is used in many printers for the reason that an image can be formed without contact with a print medium. Among these inkjet systems, the piezoelectric inkjet system that ejects ink using deformation of piezoelectric elements and the thermal inkjet system that ejects ink using the boiling phenomenon of ink due to thermal energy are excellent in high resolution and high-speed printability. Has characteristics.

  2. Description of the Related Art Currently, high speed and high image quality when ink is ejected onto a non-water-absorbing recording medium such as plain paper or plastic by an ink jet printer are important issues.

  Ink-jet recording continuously discharges ink (liquid) droplets as droplet n1, droplet n2, droplet n3,..., Droplet nx, and droplets n1 and n2 on a recording medium. , Droplets n3,..., Lines are formed with droplets nx, and images are formed. However, when it takes time to dry the droplets after droplet ejection, bleeding tends to occur. Also, mixing occurs between adjacent ink droplets, which not only prevents the formation of sharp images, but when using a non-water-absorbing recording medium, the recorded matter is printed immediately after printing because the drying of the solvent is slow. There were practical problems, such as the need to dry without layering. When mixing between droplets, adjacent droplets that have been struck are united to cause movement of the droplets, so that they deviate from the landing position, and when drawing thin lines, the line width is uneven. When a colored surface is drawn, color unevenness or the like occurs.

  One of the methods for suppressing image bleeding and non-uniform line width is a method for promoting ink curing. As one of them, a technique for hardening and fixing by radiation rather than volatilization of the ink solvent has been proposed. Specifically, in order to achieve both image storage stability and high-speed drying properties, a two-component ink is used and both are reacted on a recording medium. For example, a liquid having a basic polymer is attached. Then, after applying a method of recording an ink containing an anionic dye (see, for example, Patent Document 1) or a liquid composition containing a cationic substance, an ink containing an anionic compound and a coloring material is applied. A method (for example, see Patent Document 2), a recording method using a photocurable resin on one side and an ink containing a photopolymerization initiator on the other side (for example, see Patent Document 3) are disclosed.

  However, these methods have a certain effect in suppressing blurring of the image, but are insufficient for eliminating the non-uniform line width and color unevenness caused by mixing between droplets. Therefore, there is a concern that the drying speed is slow due to the presence of the dye, and the precipitated dye is likely to be unevenly distributed, resulting in a decrease in image quality.

As a technique related to the above, there is a technique in which a pigment is used as a coloring component and cured and fixed by radiation (for example, see Patent Document 4). Here, a pixel is formed using either an ink containing a solidifying monomer and an ink containing a pigment dispersion of yellow (Y), magenta (M), cyan (C), or black (B). On the other hand, it is described that a pixel is formed at the same point as the image on the other side and curing is performed using ultraviolet rays, an electron beam or the like.
Japanese Unexamined Patent Publication No. 63-60783 JP-A-8-174997 Japanese Patent No. 3478495 Japanese Patent Laid-Open No. 8-21818

  However, as described above, when an image is formed using a monomer-containing ink and a pigment dispersion (Y, M, C, B) -containing ink, for example, when drawing a thin line of a desired hue, it is given in a line shape. The ink spreads in the space between the lines, or the ink easily spreads at the edge of the image where there is no adjacent ink and only one side is open. Especially, recording is performed using a non-permeable or slowly permeable recording medium having a slow ink absorption speed. In the case where the adjacent droplets are present on the medium in a non-dried state, the line width and the edge of the image are non-uniform, which causes a problem in increasing the resolution of the image.

  The present invention has been made in view of the above, and provides an ink jet recording method capable of recording a high-quality image with good fine line quality (including line width homogeneity) and a uniform image edge. It is an object to achieve this purpose. In addition, another object of the present invention is to provide an ink jet recording method capable of recording an image having no stickiness and excellent scratch resistance.

Specific means for achieving the above object are as follows.
<1> onto a recording medium, an ink A containing a coloring agent and a polymerizable or crosslinkable material, and the ink B is a polymerizable or crosslinkable material content of unrealized pigment at most 1 mass%, the ink An ink jet recording method for forming an image using an ink C having a difference in SP value of 2 or less from each of A and the ink B, wherein the recording medium is at least before the ink A is ejected in advance. After the ink C is applied to the same area as the image formed with the ink A on the upper side or an area wider than the image, the ink A is ejected on the applied ink C in an image-like manner. In the inkjet recording method, the ink B is ejected onto an image non-formation region of the recording medium to cover at least a part of the image non-formation region.

<2 > The ink jet recording method according to <1 >, wherein at least the ink C includes an organic solvent having a boiling point of 100 ° C. or higher and / or an oil-soluble polymer compound .

< 3 > The ink jet recording method according to <1 > or <2> , wherein the ink C includes a polymerization initiator that polymerizes or crosslinks at least the polymerizable or crosslinkable material .
< 4 > After forming the desired image by ejecting the ink A and the ink B, the active energy is applied to the image to polymerize or crosslink the polymerizable or crosslinkable material. 3 > The inkjet recording method according to any one of the above.
< 5 > The <1> to < 4 , wherein the recording medium is a non-penetrable recording medium or a recording medium having a time of 100 ms or more until the total liquid amount permeates when a 10 pl droplet is dropped. The inkjet recording method according to any one of the above.

  According to the present invention, it is possible to provide an ink jet recording method capable of recording a high quality image with good fine line quality (including line width homogeneity) and a uniform image edge. In addition, it is possible to record an image having no stickiness and excellent scratch resistance.

  The inkjet recording method of the present invention comprises an ink A containing at least a colorant and a polymerizable or crosslinkable material, a substantially colorless ink B containing at least a polymerizable or crosslinkable material, and the ink A and the ink B. The ink C having an SP value difference of 10 or less was used, and at least before the ink A was ejected, the ink C was applied on the recording medium in advance, and then the ink A was applied on the applied ink C. Is image-formed to form an image, and at least a part of the area other than the image forming area of the recording medium is covered with ink B.

In the present invention, as a liquid for forming an image, an ink A containing a colorant and a polymerizable or crosslinkable material, a substantially colorless ink B containing a polymerizable or crosslinkable material, an ink A and an ink Ink C having a SP value difference of 10 or less from each of B is used.
A plurality of types of ink A containing colorants having different hues may be used, and a plurality of inks A having different hues are used to form a multicolor image by ejecting droplets so that a desired image is formed. be able to. Also, for ink B and ink C, a plurality of types having different compositions may be used. Details of each ink will be described later.

  In the ink jet recording method of the present invention, at least before the ink A is deposited on the recording medium, the ink is applied to the same area as the image to be ejected with the ink A on the recording medium or to an area wider than the image. C is given.

  In the present invention, the difference in SP value between the ink A and the ink B, and the difference in SP value from the ink B, of the ink C applied in advance before the ink A and the ink B are ejected are set to 10 or less. When the difference in SP value between the ink A and the ink B is within the above range, the ink A and the ink C and the ink B and the ink C are easy to dissolve each other than between the ink A and the ink B. For example, when the droplets applied so as to overlap each other have a colorant, the ink A and the ink B can be combined with each other. Color blurring or color mixing between one droplet of a plurality of inks, or between one droplet of a plurality of inks A and the other droplets and a droplet of ink B, and avoidance of line width variation of colored line images It is effective.

  In order to adjust the difference in SP value of ink C from ink A and the difference in SP value from ink B to 10 or less, it is necessary to adjust the properties to be water-insoluble and organic solvent-based. it can. Here, “water-insoluble” means that the solubility in water is 1 g or less with respect to 100 cc of water.

The SP value of the ink C can be suitably adjusted using an oleophilic solvent, a polymerizable or crosslinkable material. As one of the preferable adjustment modes, the lipophilic solvent may be contained in the range of 50% by mass to 100% by mass with respect to the total mass of the ink C. When the content of the lipophilic solvent is within the above range, the SP value can be reduced and adjusted to a range of 35 or less.
The ink A and the ink B described above can be suitably prepared in an organic solvent system containing a polymerizable or crosslinkable material. When prepared in an organic solvent system, the ink A and the ink B are particularly easy to mix with the ink C and come into contact with each other. The coalescence between the ink A and ink B droplets having the overlapping portion can be effectively avoided. Thereby, as described above, it is possible to effectively prevent the occurrence of blurring of the image and line width variations such as fine lines in the image.

  As for ink C, the SP value is preferably 35 or less as described above. When the SP value is 35 or less, the ink C can be prepared in an oil-soluble organic solvent system, and the affinity between the ink C and the ink A and the ink B containing a polymerizable or crosslinkable material as described above. Even when ink A and ink B are applied so as to have overlapping portions, the coalescence of droplets is suppressed, and the effect of blurring and color mixing of the image and the occurrence of line width variations such as fine lines in the image is effective. Can be prevented.

  The SP value of ink C is more preferably 30 or less, and particularly preferably 28 or less. Further, the difference in SP value between ink A and ink B is more preferably 25 or less.

The SP value is defined for various solvents and solutes, and is a value indicating the ease of dissolution between solvent / solvent and between solvent / solute. This value is calculated from the change in energy when the solvent and the solvent are mixed, and when the solute dissolves in the solvent. Specifically, the value is calculated by the SP value calculation program by Tohoku University RLsmith. Is. In the calculation, with reference to 25 ° C., except for compounds not containing carbon atoms, the structural units such as polymers and polyethylene chains are saturated repeating units having a bond (for example, —CH ₂ —CH (C in the case of styrene). ₆ H ₅ ) −] and water (H ₂ O) is calculated as 47.8.

  In the ink jet recording method of the present invention, ink A and ink B are ejected using an ink jet nozzle, and ink C is not necessarily limited to application by jetting using an ink jet nozzle, but other means such as coating. It can be given by. That is, the ink C is applied on the recording medium in advance to the same area as the image formed by droplets of the colored ink A or an area wider than the image, and then the ink A is ejected using an inkjet nozzle. And ink B are ejected.

  Next, a description will be given of applying means for applying the ink C onto the recording medium. The droplet ejecting means for ejecting the ink A and the ink B will be described focusing on the ejection using the inkjet nozzle as described above. A specific example is shown below.

(I) Coating using a coating device A mode in which an image is recorded by coating ink C onto a recording medium using a coating device and then ejecting ink A and ink B with an inkjet nozzle is preferable. is there.

The coating apparatus is not particularly limited and can be appropriately selected from known coating apparatuses according to the purpose, for example, an air doctor coater, a blade coater, a lot coater, a knife coater, a squeeze coater, an impregnation coater, Examples include reverse roll coaters, transfer roll coaters, gravure coaters, kiss roll coaters, cast coaters, spray coaters, curtain coaters, and extrusion coaters. For details, see Yuji Harasaki's “Coating Engineering”.
The ink jet nozzle is not particularly limited and can be appropriately selected from known nozzles according to the purpose. The ink jet recording method will be described later.

  In addition, other liquids other than ink A, ink B, and ink C may be used, and the other liquid may be applied to the recording medium by any method such as coating by the coating apparatus or jetting by an inkjet nozzle. In addition, the timing of application is not particularly limited. In the case of containing a colorant, it is preferable to spray by an ink jet nozzle, and it is preferable to apply after applying the ink C.

(Ii) Ejection by inkjet nozzle A mode in which an image is recorded by ejecting ink C by an inkjet nozzle and then ejecting ink A and ink B by an inkjet nozzle is preferable. The ink jet nozzle is the same as described above.

  In this case as well, liquids other than ink A, ink B, and ink C may be applied to the recording medium by any method such as application by an application device or injection by an inkjet nozzle. The timing is not particularly limited. In the case of containing a colorant, it is preferable to eject the ink from an ink jet nozzle, and it is preferable that the ink C is further ejected after being ejected from the nozzle.

Next, an ejection method (inkjet recording method) using an inkjet nozzle will be described.
In the present invention, for example, a charge control method that ejects ink using electrostatic attraction, a drop-on-demand method (pressure pulse method) that uses the vibration pressure of a piezo element, and an electric signal is converted into an acoustic beam into ink. Known systems such as an acoustic ink jet system that irradiates and discharges ink using radiation pressure, and a thermal ink jet (bubble jet (registered trademark)) system that uses ink to form bubbles by heating ink and generate pressure Is preferred.
Inkjet recording methods include a method of ejecting a large number of low-density inks called photo inks in a small volume, a method of improving image quality using a plurality of inks having substantially the same hue and different densities, and colorless and transparent inks. The method using is included.

  In the case of the applying means (i), at least the ink A and the ink B are ink-jetted on the recording medium on which the ink C has been applied in advance (preferably on the ink C previously applied on the recording medium). A droplet is ejected by a recording method to form an image. In the case of applying means (ii) above, on the recording medium to which the ink C has been applied in advance by the ink jet recording method (preferably, on the ink C previously applied to the recording medium by the ink jet recording method). Further, at least ink A and ink B are ejected by an ink jet recording method to form an image.

  In the present invention, after the ink C is applied as described above, the ink A is ejected in an image-like manner on the recording medium to which the ink C is previously applied, and an image is formed by the ink A. Ink B is further ejected onto a non-image non-forming area to cover at least a part of the non-image forming area.

In the present invention, colorless ink B is ejected onto an image non-formation area other than the image formation area where ink droplets are formed using ink A, and at least one of the image non-formation area, that is, the exposed portion of the recording medium. By covering the portion with ink B and covering at least part of the non-image forming area with the coating layer, ink B is present adjacent to ink A constituting the image, and spreading of ink A is suppressed. In addition, it is possible to effectively prevent variations in the line width of fine lines in the image formed by droplet ejection, distortion of lattice lines, and unevenness due to swelling of the edge of the image.
Further, as described above, the SP value is adjusted between the ink A, the ink B, and the ink C, so that the ink A and the ink B have affinity with the ink C and can maintain the dot shape. It has become. From the viewpoint of maintaining a better dot shape, it is effective to apply ink C over a wider range than an image formed by ink A.
At this time, it is preferable that the ink A and the ink B are ejected within 1 second or less after the ink C is applied onto the recording medium.

Ink A and ink B may be ejected so as to have an overlapping portion, or a plurality of inks A may be used so that a droplet of one ink A overlaps a droplet of another ink A. it can. Particularly in the latter case, since the preceding droplet and the following droplet have an overlapping portion, the number of droplet ejection per unit length is increased, and higher resolution image recording is possible.
In the case of droplet ejection with an overlapping portion, for example, in the latter case, the overlapping ratio in the overlapping portion after one second from the subsequent droplet ejection after the preceding droplet ejection is 10% or more and 90% or less. It is preferable that droplets be ejected in such a manner. It is effective for higher resolution image recording. Among these, the overlapping rate is preferably 20% or more and 80% or less, and more preferably 30% or more and 70% or less.

The overlapping rate is an index indicating at what ratio the adjacent droplets (droplet n ¹ , droplet n ² ) of the same color or different colors overlap. Assuming that the diameter of the droplet after landing on the recording medium is a, the overlapping rate is 50% when ½a overlaps. Adjacent droplets that are ejected adjacently can maintain the droplet ejection shape without being united with each other, but in the present invention, the overlapping rate is b as the droplet radius after 1 second after droplet ejection, When the interval between adjacent droplets is c, it is expressed as 100 (2b-c) / 2b [%].

  Moreover, there is no restriction | limiting in particular in the droplet ejection amount of the ink A and the ink B, It can select according to the sharpness of a recorded image. Generally, about 0.5 pL (picoliter; the same applies hereinafter) to 100 pL per droplet is preferable. The ink C is not particularly limited as long as it can be applied to the same area as the image formed with ink A (and ink B) or to an area wider than the image. When droplets are dropped, an appropriate amount can be selected in the above-mentioned range or a larger amount per droplet.

  At the time of image recording, as the balance of the amount of ink C applied per droplet of ink A and ink B, the amount of ink C applied (mass ratio) when the amount of ink A or ink B is 1 is 0. The range of 0.05 to 5 is preferable, the range of 0.07 to 1 is more preferable, and the range of 0.1 to 1 is particularly preferable.

  Ink A and ink B are preferably ejected with a droplet size of 0.1 pL or more and 100 pL or less (preferably by an inkjet nozzle). When the droplet size is within the above range, it is effective in that high-definition drawing is possible and that the polymerizable compound and the initiator can be mixed uniformly. More preferably, it is 0.5 pL or more and 50 pL or less.

  Further, it is preferable that the droplet ejection interval of ink A, the droplet ejection interval of ink B, and the droplet ejection interval of ink A and ink B are in the range of 0.001 seconds to 10 seconds. It is effective in that the effect of the present invention can be remarkably exhibited when the droplet ejection interval is within the above range. The droplet ejection interval is more preferably 0.01 seconds or more and 8 seconds or less, and 0.05 seconds or more and 5 seconds or less.

  The physical properties of ink A, ink B, and ink C ejected onto the recording medium by the ink jet recording method vary depending on the apparatus, but generally the viscosity (25 ° C.) is in the range of 5 to 100 mPa · s. 10 to 80 mPa · s is more preferable, and the surface tension is preferably in the range of 20 to 60 mN / m, and more preferably in the range of 30 to 50 mN / m. In the relationship between ink A or ink B and ink C, the difference in viscosity (25 ° C.) is preferably within 25 mPa · s, and the difference in surface tension is preferably within 20 mN / m.

In the present invention, after the ink C is applied in advance as described above, and the ink A and the ink B are subsequently deposited, from the viewpoint of obtaining excellent fixability, a recording image is formed by applying active energy. A fixing step can be provided. By imparting active energy, the polymerization reaction of the contained polymerizable or crosslinkable material and the curing reaction by crosslinking can be promoted, and a stronger image can be formed more efficiently. For example, in a system including a polymerization initiator, generation of active species due to decomposition of the polymerization initiator is promoted by application of active energy such as actinic light and heating, and due to the increase of active species and temperature rise, the result is due to the active species. The curing reaction by polymerization or crosslinking of the polymerizable or crosslinkable material is accelerated.
The application of active energy can be suitably performed by irradiation with active light or heating.

Examples of the active light include ultraviolet rays and visible rays, as well as α rays, γ rays, X rays, electron rays, and the like. Among these, ultraviolet rays and visible rays are preferably used from the viewpoint of cost and safety, and ultraviolet rays are particularly preferred.
The amount of energy required for the curing reaction varies depending on the type and content of the polymerization initiator, but is generally about 1 to 500 mJ / cm ² .

In addition, when energy is applied by heating, it is preferable to heat for 0.1 to 1 second under the condition that the surface temperature of the recording medium is in a temperature range of 40 to 80 ° C.
Heating can be performed using a non-contact type heating means, such as a heating means for passing through a heating furnace such as an oven, a heating means by full exposure of ultraviolet light to visible light to infrared light, etc. are suitable. It is. Examples of light sources suitable for exposure as the heating means include metal halide lamps, xenon lamps, tungsten lamps, carbon arc lamps, mercury lamps and the like.

  Next, the ink A, the ink B and the ink C used in the ink jet recording method of the present invention, various components constituting them, a recording medium, and the like will be described in detail.

-Ink A-
The ink A according to the present invention forms a recorded image by ejecting ink onto an after-mentioned ink C previously applied onto a recording medium, and includes at least a colorant and a polymerizable or crosslinkable material. If necessary, it can be constituted by using a polymerization initiator, a lipophilic solvent and other components.

<Polymerizable or crosslinkable material>
Ink A contains at least one polymerizable or crosslinkable material. The polymerizable or crosslinkable material has a function of causing a polymerization reaction by an initiating species such as a radical generated from a polymerization initiator described later, and curing.

  The polymerizable or crosslinkable material may be a known polymerizable or crosslinkable material that cures by causing a reaction such as a radical polymerization reaction, a cationic polymerization reaction, or a dimerization reaction (hereinafter, generally referred to as “polymerizable material”). ) Can be applied. For example, an addition polymerizable compound having at least one ethylenically unsaturated double bond, an epoxy compound, an oxetane compound, an oxirane compound, a polymer compound having a maleimide group in the side chain, and photodimerization adjacent to an aromatic nucleus Examples include a cinnamyl group having a possible unsaturated double bond, a polymer compound having a cinnamylidene group or a chalcone group in the side chain, and an addition polymerizable compound having at least one ethylenically unsaturated double bond is more preferable. Particularly preferred are those selected from compounds having at least one terminal ethylenically unsaturated bond, more preferably two or more (monofunctional or polyfunctional compounds). Specifically, it can be appropriately selected from those widely known in the industrial field according to the present invention, for example, monomers, prepolymers, that is, dimers, trimers and oligomers, or mixtures thereof, and Those having a chemical form such as a copolymer of

  The polymerizable or crosslinkable material preferably has a polymerizable group such as an acryloyl group, a methacryloyl group, an allyl group, a vinyl group or an internal double bond group (such as maleic acid) in the molecule. A compound having an acryloyl group or a methacryloyl group is preferred in that a curing reaction can occur.

  Examples of the polyfunctional compound include a vinyl group-containing aromatic compound, an (meth) acrylate that is an ester of a divalent or higher alcohol and (meth) acrylic acid, an amide of a divalent or higher amine and (meth) acrylic acid. It can be obtained by combining (meth) acrylamide, polyester (meth) acrylate obtained by introducing (meth) acrylic acid into polycaprolactone, ester obtained by combining polybasic acid and dihydric alcohol, or coupling of alkylene oxide and polyhydric alcohol. Polyether (meth) acrylate in which (meth) acrylic acid is introduced into ether, (meth) acrylic acid is introduced into epoxy resin, or epoxy (meth) obtained by reacting a bivalent or higher alcohol with an epoxy-containing monomer Acrylate, urethane acrylate with urethane bond, amino resin Relate, acrylic resin acrylate, alkyd resin acrylate, spirane resin acrylate, silicone resin acrylate, reaction product of unsaturated polyester and photopolymerizable monomer, reaction product of waxes and polymerizable monomer, and the like. .

Among them, (meth) acrylate, polyester (meth) acrylate, polyether (meth) acrylate, epoxy acrylate, urethane acrylate, acrylic resin acrylate, silicone resin acrylate, reaction product of unsaturated polyester and the photopolymerizable monomer are preferable. Acrylate, polyester acrylate, polyether acrylate, epoxy acrylate, and urethane acrylate are particularly preferable.
In addition, in this specification, (meth) acrylic acid shows that it can take both acrylic acid and methacrylic acid.

  Specific examples of the polyfunctional compound include divinylbenzene, 1,3-butanediol diacrylate, 1,6-hexanediol diacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate, dipentaerythritol hexaacrylate, 1, 6-acryloylaminohexane, hydroxypivalate ester neopentyl glycol diacrylate, polyester acrylate having a (meth) acryloyl group at the molecular chain end of a polyester having a molecular weight of 500 to 30,000 consisting of a dibasic acid and a dihydric alcohol, polyethylene glycol di An acrylate, an epoxy acrylate having a molecular weight of 450 to 30,000 having a bisphenol (A or S, F) skeleton, and a skeleton of a phenol novolac resin Epoxy acrylates amount from 600 to 30,000, the reaction product of a polyvalent isocyanate and a hydroxyl group (meth) acrylate monomer having a molecular weight of 350 to 30,000, and urethane modified products having urethane bonds and the like in the molecule.

Examples of the monofunctional compound include (meth) acrylate, styrene, acrylamide, vinyl group-containing monomers (vinyl esters, vinyl ethers, N-vinyl amide, etc.), (meth) acrylic acid, and the like (meth) Acrylates, acrylamides, vinyl esters and vinyl ethers are preferred, and (meth) acrylates and acrylamides are particularly preferred.
The polymerizable compound may be unsubstituted or may have a substituent, and examples of the substituent that can be introduced include a halogen atom, a hydroxyl group, an amide group, and a carboxylic acid group.

  Specific examples of the monofunctional compound include hydroxyethyl acrylate, glycidyl acrylate, tetrahydrofurfuryl acrylate, dicyclopentenyl acrylate, 2-acryloyloxyethyl phosphate, allyl acrylate, N, N-dimethylaminoethyl acrylate, N, N- Dimethylacrylamide, N, N-diethylaminopropylacrylamide, N-butoxymethylacrylamide, acryloylmorpholine, 2-hydroxyethyl vinyl ether, N-vinylformamide, N-vinylacetamide, 2-cyclohexylcarbamoyloxyethyl acrylate, polybutyl acrylate moiety on ester An acrylate having a polydimethylsiloxane moiety in an ester

The polymerizable or crosslinkable material may be used alone or in combination of two or more.
The content of the polymerizable or crosslinkable material in the ink A is preferably in the range of 50 to 99.6% by mass, and in the range of 70 to 99.0% by mass with respect to the total solid content (mass) of the ink A. Is more preferable, and the range of 80 to 99.0% by mass is more preferable.

<Colorant>
Ink A contains at least one colorant. The ink A may use not only a single type but also a plurality of types, and can be configured so as to be able to record a monochromatic or multicolor visible image.
The colorant may be contained in ink B, ink C, or other liquid other than ink A.

The colorant is not particularly limited, and can be appropriately selected from known water-soluble dyes, oil-soluble dyes, pigments, and the like. Among them, the ink A, the ink B, and the ink C according to the present invention are preferably configured in an oily organic solvent system from the viewpoint of the effect of the present invention, and are easily dispersed and dissolved in an oil-soluble medium. It is preferable to use soluble dyes and pigments.
Hereinafter, the oil-soluble dye and pigment suitable for the present invention will be mainly described.

~ Oil-soluble dye ~
There is no restriction | limiting in particular as oil-soluble dye, Any things can be selected and used. Hereinafter, oil-soluble dyes are exemplified for each hue.
Here, “oil-soluble” means having a solubility of 1 g or less with respect to 100 cc of water.

  Examples of yellow dyes include phenols, naphthols, anilines, pyrazolones, pyridones, aryl or heteryl azo dyes having open-chain active methylene compounds as coupling components; open-chain active methylene compounds as coupling components. Azomethine dyes; methine dyes such as benzylidene dyes and monomethine oxonol dyes; quinone dyes such as naphthoquinone dyes and anthraquinone dyes, and the like. Other dye species include quinophthalone dyes, nitro / nitroso dyes, Examples include acridine dyes and acridinone dyes.

  Examples of magenta dyes include aryl or heteryl azo dyes having phenols, naphthols, and anilines as coupling components; azomethine dyes having pyrazolones and pyrazolotriazoles as coupling components; arylidene dyes, styryl dyes, and merocyanine dyes Methine dyes such as oxonol dyes; carbonium dyes such as diphenylmethane dyes, triphenylmethane dyes, xanthene dyes, quinone dyes such as naphthoquinone, anthraquinone and anthrapyridone, condensed polycyclic dyes such as dioxazine dyes Etc.

  Examples of cyan dyes include indoaniline dyes, indophenol dyes, or azomethine dyes having pyrrolotriazoles as coupling components; polymethine dyes such as cyanine dyes, oxonol dyes, and merocyanine dyes; diphenylmethane dyes, triphenylmethane dyes, Carbonium dyes such as xanthene dyes; phthalocyanine dyes; anthraquinone dyes; aryl or heteryl azo dyes having phenols, naphthols and anilines as coupling components, and indigo / thioindigo dyes.

  Each of the dyes may exhibit yellow, magenta, and cyan colors only after a part of the chromophore group is dissociated. In this case, the counter cation is an alkali metal or an inorganic substance such as ammonium. Or an organic cation such as pyridinium or quaternary ammonium salt, or a polymer cation having such a cation in a partial structure.

When an oil-soluble dye is used as the colorant, the content of the oil-soluble dye in the ink A is preferably in the range of 0.05 to 20% by mass, and 0.1 to 15% by mass with respect to the total solid content (mass). % Is more preferable, and 0.2 to 6% by mass is particularly preferable. The same applies to the case where a colorant is used for ink B, as will be described later.
In addition, when the oil-soluble dye is contained in the ink C or other liquid other than the ink A, the content of the oil-soluble dye in each liquid is 0 to 1% by mass with respect to the total solid content (mass). The range of is preferable.

~ Pigment ~
An embodiment using a pigment as the colorant is also preferable in that aggregation is likely to occur when a plurality of liquids are mixed. As the pigment, either an organic pigment or an inorganic pigment can be used, and as the black pigment, a carbon black pigment or the like is preferable. In general, pigments of three primary colors of black and cyan, magenta, and yellow are used, but other hues such as pigments having hues such as red, green, blue, brown, white, gold, silver, etc. Metal luster pigments, colorless or light extender pigments, and the like can also be used depending on the purpose.

  In addition, particles having silica, alumina, resin, or the like as a core material and having a dye or pigment fixed on the surface, an insoluble raked product of a dye, a colored emulsion, a colored latex, or the like can also be used as a pigment. Furthermore, resin-coated pigments can also be used. This is called a microcapsule pigment, and commercially available products such as those manufactured by Dainippon Ink and Chemicals and Toyo Ink are available.

  The volume average particle diameter of the pigment particles contained in the liquid is preferably in the range of 10 to 250 nm, more preferably 50 to 200 nm, from the viewpoint of balance between optical density and storage stability. Here, the volume average particle diameter of the pigment particles can be measured by a measuring device such as LB-500 (manufactured by HORIBA).

When a pigment is used as the colorant, the content of the pigment in the ink A is in the range of 0.1 to 20% by mass with respect to the total solid content (mass) from the viewpoint of optical density and stability during jetting. Is preferable, and the range of 1-10 mass% is more preferable. The same applies to the case where a colorant is used for ink B, as will be described later.
Further, when the pigment is contained in the ink C or other liquid other than the ink A, the content of the pigment in each liquid is preferably in the range of 0 to 1% by mass with respect to the total solid content (mass). .

  The colorant may be used alone or in combination of two or more. Different colorants may be used for each droplet and liquid to be ejected, or the same colorant may be used.

Ink A is prepared such that the difference in SP value from ink C described later is 10 or less. The difference in SP value with ink C applied in advance before ink droplet ejection is high at 10 or less, and the affinity is high, and it effectively prevents droplets from coalescing when in contact with ink B described later. Can do.
The SP value can be suitably adjusted using a lipophilic solvent, a polymerizable compound, etc., which will be described later. For example, the SP value can be lowered by increasing the ratio of the lipophilic solvent in the droplets.

  Details and preferred embodiments of the lipophilic solvent, the polymerization initiator, and other components that can be contained in the ink A will be described later.

-Ink B-
The ink B according to the present invention covers at least a part of an image non-formation area except for an image area formed by droplets of the ink A on a recording medium to which the ink C has been applied in advance. The composition is composed of a curable or crosslinkable material and is configured as a substantially colorless liquid. If necessary, it can be further constituted using a colorant, a lipophilic solvent, a polymerization initiator, and other components.

  Here, “substantially colorless” means that there is no color that can form a color image and that it is transparent. Transparency is the degree that does not constitute a color image by reflection of received light. The property of transmitting light. Here, “substantially colorless” means that the pigment content is preferably 1% or less, more preferably 0.5% or less, and 0.1% or less. Particularly preferred.

The ink B may have the same composition as the ink A described above except for the colorant, or may be configured in a different composition.
The details (specific examples, content, etc.) of the polymerizable or crosslinkable material and the colorant are as described above, and the lipophilic solvent, the polymerization initiator, and other components will be described later.

-Ink C-
In the present invention, before the above-described ink A and ink B are ejected, the same area as the image formed with ink A on the recording medium is formed in advance on the recording medium or wider than the image. Ink C having a SP value difference of 10 or less from each of ink A and ink B is applied to the region.

  Ink C can be composed of a polymerizable or crosslinkable material, a colorant, a high boiling point organic solvent, a lipophilic solvent other than a high boiling point organic solvent, a polymerization initiator, and other components, preferably a polymerization initiator. Can be configured. More preferably, it further contains a high-boiling organic solvent and an oil-soluble polymer compound, and if necessary, a colorant, a polymerizable or crosslinkable material and other components can be used. The details (specific examples, content, etc.) of the polymerizable or crosslinkable material and the colorant are as described above.

<Polymerization initiator>
Ink C can suitably contain at least one polymerization initiator. This polymerization initiator is a compound that generates an initiating species such as a radical upon application of actinic light, heat, or both, and initiates, accelerates, and cures a polymerization reaction of a polymerizable or crosslinkable material. The polymerization initiator may be contained in the ink A and the ink B described above.

  This polymerization initiator is preferably contained separately from the polymerizable or crosslinkable material from the viewpoint of ensuring the storage stability of the ink A, ink B and ink C as described above. The ink C is preferably contained in the ink C other than the ink A and the ink B containing the crosslinkable material.

  As the polymerization initiator, a known photopolymerization initiator (including a radical generator), a thermal polymerization initiator, a compound having a bond with a small bond dissociation energy, and the like can be selected and used.

  Examples of photopolymerization initiators (including radical generators) include organic halogenated compounds, carbonyl compounds, organic peroxide compounds, azo polymerization initiators, azide compounds, metallocene compounds, hexaarylbiimidazole compounds, organic boric acid Compounds, disulfonic acid compounds, onium salt compounds, and the like.

Preferable examples of the polymerization initiator include the following photopolymerization initiators.
For example, light of acetophenone derivative, benzophenone derivative, benzyl derivative, benzoin derivative, benzoin ether derivative, benzyldialkyl ketal derivative, thioxanthone derivative, acylphosphine oxide derivative, metal complex, p-dialkylaminobenzoic acid, azo compound, peroxide compound, etc. Examples of the polymerization initiator include acetophenone derivatives, benzyl derivatives, benzoin ether derivatives, benzyl dialkyl ketal derivatives, thioxanthone derivatives, and acylphosphine oxide derivatives. Among them, acetophenone derivatives, benzoin ether derivatives, benzyl dialkyl ketal derivatives, Acylphosphine oxide derivatives are particularly preferred.

Specific examples of the photopolymerization initiator include acetophenone, 2,2-diethoxyacetophenone, p-dimethylaminoacetophenone, p-dimethylaminopropiophenone, benzophenone, p, p′-dichlorobenzophenone, p, p. '-Bisdiethylaminobenzophenone, Michler's ketone, benzyl, benzoin, benzoin methyl ether, benzoin isopropyl ether, benzoin-n-propyl ether, benzoin isobutyl ether, benzyldimethyl ketal, 1-hydroxy-cyclohexyl phenyl ketone, tetramethylthiuram monosulfide, thioxanthone , 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,2-dimethylpropioyl diphenylphosphine oxide, 2-methyl 2-ethylhexanoyldiphenylphosphine oxide, 2,6-dimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6 -Dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, 2,3,6-trimethylbenzoyl-diphenylphosphine oxide, bis (2,3,6-trimethylbenzoyl) -phenylphosphine oxide, 2, 4,6-trimethoxybenzoyl-diphenylphosphine oxide, 2,4,6-trichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylnaphthyl phospho Chromatography, bis (eta ^{5-2,4-cyclopentadiene-1-yl)} - bis (2,6-difluoro-3-(1H-pyrrol-1-yl) - phenyl) titanium, p- dimethylaminobenzoic acid , P-diethylaminobenzoic acid, azobisisobutyronitrile, 1,1′-azobis (1-acetoxy-1-phenylethane), benzoin peroxide, di-tert-butyl peroxide and the like.

  In addition to the above, examples of other preferable photopolymerization initiators include photopolymerization initiation described on pages 65 to 148 of “Ultraviolet curing system” by Kato Kiyomi (published by General Technology Center Co., Ltd .: 1989). An agent can be mentioned.

  The polymerization initiator preferably has excellent sensitivity. For example, it is not preferable to use one that causes thermal decomposition at a temperature of 80 ° C. or lower from the viewpoint of storage stability, and thermal decomposition occurs at a temperature up to 80 ° C. It is preferred to select a polymerization initiator that is not present.

  A polymerization initiator can be used 1 type or in combination of 2 or more types. Moreover, a well-known sensitizer can also be used together for the purpose of a sensitivity improvement in the range which does not impair the effect of this invention.

  The content of the polymerization initiator in the ink C is preferably 0.5 to 20% by mass and more preferably 1 to 15% by mass with respect to the whole ink from the viewpoints of stability over time, curability, and curing speed. 3 to 10% by mass is preferable. When the content is too large, precipitation or separation with time may occur, or performance such as strength and rubbing resistance of the ink after curing may be deteriorated.

The polymerization initiator may be contained in the ink C and may be contained in the ink A and the ink B described above. In this case, the storage stability of the ink A and the ink B can be maintained within a desired level. It can be appropriately selected and contained.
Further, the polymerization initiator may not be contained in the ink C but may be contained in the ink A and the ink B described above. In this case, the content in the ink A and the ink B is preferably 0.5 to 20% by mass and more preferably 1 to 15% by mass with respect to the entire ink.

<High boiling point organic solvent>
The ink C can be suitably configured using at least one kind of lipophilic solvent, particularly a high boiling point organic solvent. The high-boiling organic solvent is effective in preventing the contact between adjacent droplets, for example, droplets of ink A that are deposited with overlapping portions, droplets between the droplets of ink A and ink B, and The coalescence between the droplets is suppressed, which is effective in preventing the occurrence of image bleeding and line width variations such as fine lines in the image, and the SP value of the ink C can be adjusted to a range described later.

  The high-boiling organic solvent may be contained in the ink A and the ink B described above with or without the ink C. Further, it may be contained in a liquid other than ink C and ink A and ink B.

  As the high-boiling organic solvent, (1) a viscosity at 25 ° C. of 100 mPa · s or less or a viscosity at 60 ° C. of 30 mPa · s or less and (2) a boiling point higher than 100 ° C. is preferable.

  A high boiling point organic solvent that does not satisfy any of the above viscosity conditions (1) may increase the viscosity and hinder the application to the recording medium, and satisfy the boiling point condition (2). If the organic solvent has no high boiling point, the boiling point becomes too low and the solvent evaporates during image recording, which may reduce the effect of the present invention.

  Among the conditions (1), the viscosity at 25 ° C. is preferably in the range of 70 mPa · s or less, more preferably in the range of 40 mPa · s or less, and particularly preferably in the range of 20 mPa · s or less. The viscosity at 60 ° C. is more preferably in the range of 20 mPa · s or less, and particularly preferably in the range of 10 mPa · s or less. Regarding the condition (2), the boiling point is more preferably in the range of 150 ° C. or more, and particularly preferably in the range of 170 ° C. or more. Moreover, as a lower limit of melting | fusing point, the range of 80 degrees C or less is preferable. Furthermore, the solubility (25 ° C.) of water is preferably 4 g or less, more preferably 3 g or less, further preferably 2 g or less, and particularly preferably 1 g or less.

  The “viscosity” here is a viscosity determined using a RE80 viscometer manufactured by Toki Sangyo Co., Ltd. The RE80 type viscometer is a conical rotor / flat plate type viscometer corresponding to the E type, and the rotor code No. 1 rotor was used and the measurement was performed at a rotation speed of 10 rpm. However, for those having a viscosity higher than 60 mPa · s, the rotational speed is 5 r.p.m., 2.5 r.p.m., 1 r.p.m., 0.5 r.p.m. The measurement was performed by changing to.

  The “water solubility” is the saturation concentration of water in the high boiling point organic solvent at 25 ° C., and means the mass (g) of water that can be dissolved in 100 g of the high boiling point organic solvent at 25 ° C.

  As the high boiling point organic solvent, compounds represented by the following formulas [S-1] to [S-9] are preferable.

In the formula [S-1], R ₁ , R ₂ and R ₃ each independently represents an aliphatic group or an aryl group. A, b and c each independently represent 0 or 1;

In the formula [S-2], R ₄ and R ₅ each independently represents an aliphatic group or an aryl group, and R ₆ represents a halogen atom (F, Cl, Br, I and so on), an alkyl group, an alkoxy group, Represents an aryloxy group, an alkoxycarbonyl group or an aryloxycarbonyl group, and d represents an integer of 0 to 3. When d is plural, plural R ₆ may be the same or different.

In the formula [S-3], Ar represents an aryl group, e represents an integer of 1 to 6, and R ₇ represents an e-valent hydrocarbon group or a hydrocarbon group bonded to each other through an ether bond.

In the formula [S-4], R ₈ represents an aliphatic group, f represents an integer of 1 to 6, and R ₉ represents an f-valent hydrocarbon group or a hydrocarbon group bonded to each other through an ether bond.

In the formula [S-5], g represents an integer of 2 to 6, R ₁₀ represents a g-valent hydrocarbon group (excluding an aryl group), and R ₁₁ represents an aliphatic group or an aryl group.

In the formula [S-6], R ₁₂ , R ₁₃ and R ₁₄ each independently represents a hydrogen atom, an aliphatic group or an aryl group. X represents —CO— or —SO ₂ —. R ₁₂ and R ₁₃ or R ₁₃ and R ₁₄ may be bonded to each other to form a ring.

In the formula [S-7], R ₁₅ represents an aliphatic group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, an arylsulfonyl group, an aryl group or a cyano group, and R ₁₆ represents a halogen atom, an aliphatic group or an aryl group. Represents a group, an alkoxy group or an aryloxy group, and h represents an integer of 0 to 3. When h is plural, plural R ₁₆ may be the same or different.

In the formula [S-8], R ₁₇ and R ₁₈ each independently represents an aliphatic group or an aryl group, R ₁₉ represents a halogen atom, an aliphatic group, an aryl group, an alkoxy group or an aryloxy group, and i Represents an integer of 0 to 5. When i is plural, plural R ₁₉ may be the same or different.

In the formula [S-9], R ₂₀ and R ₂₁ each independently represents an aliphatic group or an aryl group. j represents 1 or 2; R ₂₀ and R ₂₁ may be bonded to each other to form a ring.

In the formulas [S-1] to [S-9], when R _{1 to} R ₆ , R ₈ and R _{11 to} R ₂₁ are an aliphatic group or a group containing an aliphatic group, the aliphatic group is a straight chain, It may be branched or cyclic, and may contain an unsaturated bond or may have a substituent. Examples of the substituent include a halogen atom, an aryl group, an alkoxy group, an aryloxy group, an alkoxycarbonyl group, a hydroxyl group, an acyloxy group, and an epoxy group.

In the formulas [S-1] to [S-9], R _{1 to} R ₆ , R ₈ and R _{11 to} R ₂₁ are cyclic aliphatic groups, that is, cycloalkyl groups, or groups containing cycloalkyl groups. Sometimes, the cycloalkyl group may contain an unsaturated bond in the 3- to 8-membered ring, and may have a substituent or a bridging group. Examples of the substituent include a halogen atom, an aliphatic group, a hydroxyl group, an acyl group, an aryl group, an alkoxy group, and an epoxy group, and examples of the crosslinking group include methylene, ethylene, isopropylidene, and the like.

In the formulas [S-1] to [S-9], when R _{1 to} R ₆ , R ₈ , R _{11 to} R ₂₁ , Ar is an aryl group or a group containing an aryl group, the aryl group is a halogen atom, aliphatic It may be substituted with a substituent such as a group, an aryl group, an alkoxy group, an aryloxy group, or an alkoxycarbonyl group.

In the formulas [S-3], [S-4], and [S-5], when R ₇ , R _9, or R ₁₀ is a hydrocarbon group, the hydrocarbon group is a cyclic structure (for example, a benzene ring, a cyclopentane ring, A cyclohexane ring) or an unsaturated bond, and may have a substituent. Examples of the substituent include a halogen atom, a hydroxyl group, an acyloxy group, an aryl group, an alkoxy group, an aryloxy group, and an epoxy group.

Hereinafter, among the high boiling point organic solvents represented by the formulas [S-1] to [S-9], particularly preferred high boiling point organic solvents will be described.
In the formula [S-1], R ₁ , R ₂ and R ₃ are each independently an aliphatic group having 1 to 24 (preferably 4 to 18) carbon atoms (for example, n-butyl, n-hexyl, n -Octyl, EH-octyl, 2-ethylhexyl, 3,3,5-trimethylhexyl, 3,5,5-trimethylhexyl, n-dodecyl, n-octadecyl, benzyl, oleyl, 2-chloroethyl, 2,3-dichloro Propyl, 2-butoxyethyl, 2-phenoxyethyl, cyclopentyl, cyclohexyl, 4-t-butylcyclohexyl, 4-methylcyclohexyl) or an aryl group having 6 to 24 (preferably 6 to 18) carbon atoms (for example, phenyl, Cresyl, p-nonylphenyl, xylyl, cumenyl, p-methoxyphenyl, p-methoxycarbonylphenyl) are preferred Yes. Among these, R ₁ , R ₂ and R ₃ are particularly n-hexyl, n-octyl, EH-octyl, 2-ethylhexyl, 3,5,5-trimethylhexyl, n-dodecyl, 2-chloroethyl, 2- Butoxyethyl, cyclohexyl, phenyl, cresyl, p-nonylphenyl and cumenyl are preferred.
a, b, and c are each independently 0 or 1, and more preferably, all of a, b, and c are 1.

In the formula [S-2], R ₄ and R ₅ are each independently an aliphatic group having 1 to 24 (preferably 4 to 18) carbon atoms (for example, the same group as the aliphatic group mentioned for R ₁ above). , Heptyl, ethoxycarbonylmethyl, 1,1-diethylpropyl, 2-ethyl-1-methylhexyl, cyclohexylmethyl, 1-ethyl-1,5-dimethylhexyl, 3,5,5-trimethylcyclohexyl, menthyl, bornyl, 1-methylcyclohexyl) or an aryl group having 6 to 24 (preferably 6 to 18) carbon atoms (for example, the aryl group mentioned for R ₁ , 4-t-butylphenyl, 4-t-octylphenyl, 1, 3,5-trimethylphenyl, 2,4, -di-t-butylphenyl, 2,4, -di-t-pentylphenyl) are preferred. Among these, R ₄ and R ₅ are more preferably aliphatic groups, and particularly preferably n-butyl, heptyl, 2-ethylhexyl, n-dodecyl, 2-butoxyethyl, and ethoxycarbonylmethyl.
R ₆ is a halogen atom (preferably a chlorine atom), an alkyl group having 1 to 18 carbon atoms (eg, methyl, isopropyl, t-butyl, n-dodecyl), an alkoxy group having 1 to 18 carbon atoms (eg, methoxy, n -Butoxy, n-octyloxy, methoxyethoxy, benzyloxy), an aryloxy group having 6 to 18 carbon atoms (for example, phenoxy, p-tolyloxy, 4-methoxyphenoxy, 4-t-butylphenoxy) or 2 carbon atoms A C-19 alkoxycarbonyl group (for example, methoxycarbonyl, n-butoxycarbonyl, 2-ethylhexyloxycarbonyl) or an aryloxycarbonyl group having 6 to 25 carbon atoms is preferred. Among these, R ₆ is further preferably an alkoxycarbonyl group, and particularly preferably n-butoxycarbonyl.
d is 0 or 1.

In the formula [S-3], Ar is an aryl group having 6 to 24 (preferably 6 to 18) carbon atoms (for example, phenyl, 4-chlorophenyl, 2,4-dichlorophenyl, 4-methoxyphenyl, 1-naphthyl, 4- n-butoxyphenyl, 1,3,5-trimethylphenyl, 2- (2-n-butoxycarbonylphenyl) phenyl) are preferable, and among these, Ar is phenyl, 2,4-dichlorophenyl, 2- (2 -N-Butoxycarbonylphenyl) phenyl is preferred.
e is an integer of 1 to 4 (preferably 1 to 3).
R ₇ is an e-valent hydrocarbon group having 2 to 24 (preferably 2 to 18) carbon atoms [for example, the aliphatic group mentioned above for R ₄ , n-octyl, the aryl group mentioned for R ₄ ,-( CH _{2) 2} -,

] Or an e-valent hydrocarbon group having 4 to 24 (preferably 4 to 18) carbon atoms and bonded to each other by an ether bond [for example, —CH ₂ CH ₂ OCH ₂ CH ₂ —, —CH ₂ CH ₂ (OCH _{2 CH 2) 3 -, - CH} 2 CH 2 CH 2 OCH 2 CH 2 CH 2 -,

] Is preferable. Among these, R ₇ is more preferably an alkyl group, and particularly preferably n-butyl, n-octyl and 2-ethylhexyl.

In the formula [S-4], R ₈ is an aliphatic group having 1 to 24 (preferably 1 to 17) carbon atoms (for example, methyl, n-propyl, 1-hydroxyethyl, 1-ethylpentyl, n-heptyl, n - undecyl, n- tridecyl, pentadecyl, 8,9-epoxy heptadecyl, cyclopropyl, cyclohexyl, 4-methylcyclohexyl). among them, R ₈ in particular, n- heptyl, n- tridecyl, 1-hydroxy Ethyl, 1-ethylpentyl, and 8,9-epoxyheptadecyl are preferred.
f is an integer of 1 to 4 (preferably 1 to 3).
R ₉ is a hydrocarbon group having 2 to 24 (preferably 2 to 18) f-valent carbon atoms or a hydrocarbon group linked to each other by an ether bond having 4 to 24 (preferably 4 to 18) f-valent carbon atoms. (For example, the groups mentioned for R ₇ , 1-methyl-2-methoxyethyl, 2-hexyldecyl) are preferable, and among these, R ₉ is particularly 2-ethylhexyl, 2-hexyldecyl, 1-methyl-2 -Methoxyethyl,

Is preferred.

In the formula [S-5], g is 2 to 4 (preferably 2 or 3).
R ₁₀ represents a g-valent hydrocarbon group [for example, —CH ₂ —, — (CH ₂ ) ₂ —, — (CH ₂ ) ₄ —, — (CH ₂ ) ₇ —, — (CH ₂ ) ₈ —,

Among these, R ₁₀ is particularly — (CH ₂ ) ₄ —, — (CH ₂ ) ₈ —,

Is preferred.
R ₁₁ is an aliphatic group having 1 to 24 (preferably 4 to 18) carbon atoms, or an aryl group having 6 to 24 (preferably 6 to 18) carbon atoms (for example, the aliphatic groups mentioned for R ₄ above, Aryl group). Among these, R ₁₁ is more preferably an alkyl group, and n-butyl, n-octyl, and 2-ethylhexyl are particularly preferable.

In the formula [S-6], R ₁₂ is a hydrogen atom, an aliphatic group having 1 to 24 carbon atoms (preferably 3 to 20) [for example, n-propyl, 1-ethylpentyl, n-undecyl, n-pentadecyl, 2,4-di-t-pentylphenoxymethyl, 4-t-octylphenoxymethyl, 3- (2,4-di-t-butylphenoxy) propyl, 1- (2,4-di-t-butylphenoxy) propyl Cyclohexyl, 4-methylcyclohexyl, 8-N, N-diethylcarbamoyloctyl], or an aryl group having 6 to 24 (preferably 6 to 18) carbon atoms (for example, the aryl group mentioned for Ar, 3-methylphenyl) , 2-(N, N-di -n- octylcarbamoyl) phenyl). among them, R ₁₂ is especially, n- undecyl, 8-N, N-di Ji carbamoyl octyl, 3-methylphenyl, 2-(N, N-di -n- octylcarbamoyl) phenyl are preferred.
R ₁₃ and R ₁₄ are each a hydrogen atom or an aliphatic group having 1 to 24 (preferably 1 to 18) carbon atoms (eg, methyl, ethyl, isopropyl, n-butyl, n-hexyl, n-octyl, 2-ethylhexyl). , N-dodecyl, n-tetradecyl, cyclopentyl, cyclopropyl) or an aryl group having 6 to 18 carbon atoms (preferably 6 to 15) (for example, phenyl, 1-naphthyl, p-tolyl), among these, R ₁₃ and R ₁₄ are particularly preferably methyl, ethyl, n-butyl, n-octyl, n-tetradecyl and phenyl.
R ₁₃ and R ₁₄ may be bonded to each other to form a pyrrolidine ring, piperidine ring or morpholine ring together with N, and R ₁₂ and R ₁₃ may be bonded to each other to form a pyrrolidone ring or piperidine ring together with N. Also good.
X is —CO— or —SO ₂ —, and preferably X is —CO—.

In the formula [S-7], R ₁₅ is an aliphatic group having 1 to 24 (preferably 3 to 18) carbon atoms (for example, methyl, isopropyl, t-butyl, t-pentyl, t-hexyl, t-octyl, 2 -Butyl, 2-hexyl, 2-octyl, 2-dodecyl, 2-hexadecyl, t-pentadecyl, cyclopentyl, cyclohexyl), an alkoxycarbonyl group having 2 to 24 (preferably 5 to 17) carbon atoms (for example, n-butoxy) Carbonyl, 2-ethylhexyloxycarbonyl, n-dodecyloxycarbonyl), aryloxycarbonyl group having 7 to 24 carbon atoms (preferably 7 to 18) (for example, phenoxycarbonyl group, naphthoxycarbonyl group, cresyloxycarbonyl group) An alkylsulfonyl group having 1 to 24 (preferably 1 to 18) carbon atoms ( For example, methylsulfonyl, n-butylsulfonyl, n-dodecylsulfonyl), arylsulfonyl groups having 6 to 30 carbon atoms (preferably 6 to 24) (for example, p-tolylsulfonyl, p-dodecylphenylsulfonyl, p-hexadecyloxy) Phenylsulfonyl), an aryl group having 6 to 32 carbon atoms (preferably 6 to 24 carbon atoms) (for example, phenyl, p-tolyl), or a cyano group is preferable, and among these, R ₁₅ is further having 1 to 24 carbon atoms. An aliphatic group and an alkoxycarbonyl group having 2 to 24 carbon atoms are more preferable, and an aliphatic group having 1 to 24 carbon atoms is particularly preferable.
R ₁₆ is a halogen atom (preferably Cl), an aliphatic group having 1 to 24 carbon atoms (preferably 1 to 18 carbon atoms) {more preferably an alkyl group (for example, the alkyl groups mentioned for R ₁₅ above), carbon atoms 3-18 (more preferably 5-17) cycloalkyl group (for example, cyclopentyl, cyclohexyl)}, aryl group having 6-32 (preferably 6-24) carbon atoms (for example, phenyl, p-tolyl), carbon atom An alkoxy group of 1 to 24 (preferably 1 to 18) (for example, methoxy, n-butoxy, 2-ethylhexyloxy, benzyloxy, n-dodecyloxy, n-hexadecyloxy) or 6 to 32 carbon atoms (preferably Is an aryloxy group (for example, phenoxy, pt-butylphenoxy, pt-octylphenoxy, m-pen) Decylphenoxy, a p- dodecyloxy-phenoxy) Of these, R ₁₆ is further more preferably an aliphatic group having 1 to 24 carbon atoms, particularly preferably an aliphatic group having 1 to 12 carbon atoms.
h is an integer of 1-2.

In the formula [S-8], preferred examples of R ₁₇ and R ₁₈ are the same as the examples other than the hydrogen atom in R ₁₃ and R ₁₄ , and among these, R ₁₇ and R ₁₈ further have an aliphatic group. More preferred are n-butyl, n-octyl and n-dodecyl. However, R ₁₇ and R ₁₈ are not bonded to each other to form a ring.
Preferred examples of R ₁₉ are the same as R ₁₆ described above, and among these, R ₁₉ is more preferably an alkyl group and an alkoxy group, and particularly preferably n-octyl, methoxy, n-butoxy and n-octyloxy. .
i is an integer of 1-5.

In the formula [S-9], preferred examples of R ₂₀ and R ₂₁ are the same as those of R ₁ , R ₂ and R ₃ when they are not bonded to form a ring. Among these, R ₂₀ and R ₂₁ Is particularly preferably a substituted or unsubstituted aliphatic group having 1 to 24 carbon atoms.
R ₂₀ and R ₂₁ may be bonded to each other to form a ring, and the formed ring is preferably a 3- to 10-membered ring, particularly preferably a 5- to 7-membered ring.
j represents 1 or 2, and preferably j is 1.

Hereinafter, specific examples (Exemplary Compounds S-1 to S-53, Exemplified Compound S-101) of high-boiling organic solvents and the viscosity of each high-boiling organic solvent (measured by the above-mentioned means in an environment of 25 ° C. and 60 ° C.) Value; mPa · s) and boiling point (° C.).
Here, the boiling point of the high-boiling organic solvent is a value converted from the boiling point during vacuum distillation to normal pressure. In the following specific examples, those having no boiling point are confirmed not to boil at 170 ° C., and those having no viscosity at 25 ° C. are solid at 25 ° C.

Furthermore, the following compound examples can be given.

  Even if one kind of high-boiling organic solvent is used alone, two or more kinds thereof [for example, tricresyl phosphate and dibutyl phthalate, trioctyl phosphate and di (2-ethylhexyl) sebacate, dibutyl phthalate and poly (Nt- Butylacrylamide)]] may be used in combination.

  Examples of other high boiling point organic solvents and / or methods for synthesizing these high boiling point organic solvents include, for example, U.S. Pat. Nos. 2,322,027, 2,533,514, and 2, 772,163, 2,835,579, 3,594,171, 3,676,137, 3,689,271, 3,700,454, 3,748,141, 3,764,336, 3,765,897, 3,912,515, 3,936,303, 4,004 , 928, 4,080,209, 4,127,413, 4,193,802, 4,207,393, 4,220,711, No. 4,239,851, No. 4,278,757, No. 4,353,9 No. 9, No. 4,363,873, No. 4,430,421, No. 4,430,422, No. 4,464,464, No. 4,483,918, No. 4,540,657, 4,684,606, 4,728,599, 4,745,049, 4,935,321, 5,013,639 European Patent Nos. 276,319A, 286,253A, 289,820A, 309,158A, 309,159A, 309,160A, 509,311A No. 510,576A, East German Patent No. 147,009, No. 157,147, No. 159,573, No. 225,240A, British Patent No. 2,091,124A, etc. Description, JP-A-48-47335, 50 No. 26530, No. 51-25133, No. 51-26036, No. 51-27921, No. 51-27922, No. 51-149028, No. 52-46816, No. 53-1520, No. 53-1521 53-15127, 53-146622, 54-91325, 54-106228, 54-118246, 55-59464, 56-64333, 56-81836, 59-204041, 61-84641, 62-118345, 62-247364, 63-167357, 63-214744, 63-301941, 63-94552, 64-945 9454, 64-68745, JP-A-1-101543, 1-102454, 2-792, and 2 No. 4239, No. 2-43541, No. 4-29237, No. 4-30165, No. 4-232946, No. 4-346338, and the like.

  In the present invention, a high boiling organic solvent having a boiling point higher than 100 ° C. is preferable, and a high boiling organic solvent having a boiling point higher than 170 ° C. is more preferable.

  The amount of the high-boiling organic solvent added to the ink C is preferably in the range of 50% to 100% by weight, more preferably 60% to 97.5% by weight, based on the total weight of the ink C. 70 mass% or more and 95 mass% or less are especially preferable.

<Oil-soluble polymer compound>
The ink C can be suitably configured using at least one oil-soluble polymer compound. This oil-soluble polymer compound is effective in preventing the colorant from diffusing when the ink A and the ink B are applied.
The ink A containing the colorant and the colorless ink B and the ink C have a small SP value and high affinity, and the ink droplets of the inks A and B ejected with overlapping portions are combined. In addition to being suppressed, diffusion is prevented, so that it is possible to more effectively prevent the occurrence of blurring of the image and variations in line width such as fine lines in the image. Accordingly, it is possible to form a sharp line with a uniform width and bleeding while ensuring image resolution, and a high-quality image can be recorded.

The oil-soluble polymer compound is a polymer compound obtained by polymerization from the following monomers, and has a solubility in water of 1 g or less per 100 cc of water.
Examples of the monomer include (meth) acrylic acid alkyl ester [for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, (meth) N-butyl acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylic acid (Meth) acrylic acid C1-C18 alkyl ester such as lauryl, stearyl (meth) acrylate], (meth) acrylic acid cycloalkyl ester [for example, (meth) acrylic acid cyclohexyl etc.], (meth) acrylic acid aryl ester [ For example, phenyl (meth) acrylate], aralkyl ester For example, benzyl (meth) acrylate], substituted (meth) acrylic acid alkyl esters [for example, 2-hydroxyethyl (meth) acrylate], (meth) acrylamides [for example, (meth) acrylamide, dimethyl (meth) acrylamide Etc.], aromatic vinyls [eg, styrene, vinyl toluene, α-methylstyrene, etc.], vinyl esters [eg, vinyl acetate, vinyl propionate, vinyl versatate], allyl esters [eg, allyl acetate, etc.] And halogen-containing monomers [for example, vinylidene chloride, vinyl chloride, etc.], vinyl cyanides [for example, (meth) acrylonitrile, etc.], olefins [for example, ethylene, propylene, etc.] and the like.

  Among these polymerizable monomers, (meth) acrylic acid alkyl esters, (meth) acrylamides, and aromatic vinyls are preferred, (meth) methyl acrylate, (meth) acrylic acid ethyl, (meth) acrylic Propyl acid, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, ( Particularly preferred are 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and styrene. An oil-soluble polymer compound obtained by copolymerizing a monomer having a nitrogen-containing heterocyclic group, a monomer having an onium group, or a monomer having an amino group with these polymers is also a preferred embodiment.

Specific examples of the nitrogen-containing heterocyclic group include saturated heterocyclic rings (for example, aziridine, azetidine, pyrrolidine, piperidine, piperazine, morpholine, thiomorpholine, caprolactam, valerolactam), and unsaturated heterocyclic rings (for example, Imidazole, pyridine, pyrrole, pyrazole, pyrazine, pyrimidine, indole, purine, quinoline, triazine, etc.).
These nitrogen-containing heterocycles may further have a substituent, and examples of the substituent include an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a halogen atom, a hydroxyl group, a carbamoyl group, and an amino group. It is done.

  The monomer having a nitrogen-containing heterocyclic group is preferably a vinyl monomer. Specifically, N-vinylpyrrolidone, N-vinylcaprolactam, acryloylmorpholine, acryloylthiomorpholine, N-vinylimidazole, 2-methyl-1-vinylimidazole, 2-vinylpyridine, 4-vinylpyridine, N-vinylcarbazole N-methylmaleimide, N-ethylmaleimide, 2-isopropenyl-2-oxazoline and the like. Of these, N-vinylimidazole, 2-vinylpyridine, and 4-vinylpyridine are particularly preferable.

  In the monomer having an onium group, examples of the onium group include an ammonium group, a phosphonium group, and a sulfonium group, and an ammonium group is preferable.

  Examples of the monomer having an ammonium group include trimethyl-p-vinylbenzylammonium chloride, trimethyl-m-vinylbenzylammonium chloride, triethyl-p-vinylbenzylammonium chloride, triethyl-m-vinylbenzylammonium chloride, N , N-dimethyl-N-ethyl-Np-vinylbenzylammonium chloride, N, N-diethyl-N-methyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-Nn-propyl-N -P-vinylbenzylammonium chloride, N, N-dimethyl-Nn-octyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N-benzyl-Np-vinylbenzylammonium chloride, N, N Diethyl-N-benzyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N- (4-methyl) benzyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N-phenyl-N -P-vinylbenzylammonium chloride, trimethyl-p-vinylbenzylammonium bromide, trimethyl-m-vinylbenzylammonium bromide, trimethyl-p-vinylbenzylammonium sulfonate, trimethyl-m-vinylbenzylammonium sulfonate, trimethyl-p-vinylbenzyl Ammonium acetate, trimethyl-m-vinylbenzylammonium acetate, N, N, N-triethyl-N-2- (4-vinylphenyl) ethylammonium chloride, N, N, N- Liethyl-N-2- (3-vinylphenyl) ethylammonium chloride, N, N-diethyl-N-methyl-N-2- (4-vinylphenyl) ethylammonium chloride, N, N-diethyl-N-methyl- N-2- (4-vinylphenyl) ethylammonium acetate, trimethyl-2- (methacryloyloxy) ethylammonium chloride, triethyl-2- (methacryloyloxy) ethylammonium chloride, trimethyl-2- (acryloyloxy) ethylammonium chloride, Triethyl-2- (acryloyloxy) ethylammonium chloride, trimethyl-3- (methacryloyloxy) propylammonium chloride, triethyl-3- (methacryloyloxy) propylammonium chloride Trimethyl-2- (methacryloylamino) ethylammonium chloride, triethyl-2- (methacryloylamino) ethylammonium chloride, trimethyl-2- (acryloylamino) ethylammonium chloride, triethyl-2- (acryloylamino) ethylammonium chloride, Trimethyl-3- (methacryloylamino) propylammonium chloride, triethyl-3- (methacryloylamino) propylammonium chloride, trimethyl-3- (acryloylamino) propylammonium chloride, triethyl-3- (acryloylamino) propylammonium chloride, N, N-dimethyl-N-ethyl-2- (methacryloyloxy) ethylammonium chloride, N, N-die -N-methyl-2- (methacryloyloxy) ethylammonium chloride, N, N-dimethyl-N-ethyl-3- (acryloylamino) propylammonium chloride, trimethyl-2- (methacryloyloxy) ethylammonium bromide, trimethyl-3 -(Acryloylamino) propylammonium bromide, trimethyl-2- (methacryloyloxy) ethylammonium sulfonate, trimethyl-3- (acryloylamino) propylammonium acetate, monomethyldiallylammonium chloride, dimethyldiallylammonium chloride, allylamine hydrochloride, etc. Can do.

In the monomer having an amino group, examples of the amino group include —NR ¹ R ² (R ¹ and R ² are alkyl groups).
Examples of the monomer having an amino group include N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-diethylaminopropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-diethylaminopropyl (Meth) acrylamide, diallylamine, N-methyldiallylamine, N-vinylbenzyl-N, N-dimethylamine, N-vinylbenzyl-N, N-diethylamine, N-vinylbenzyl-N-ethyl-N-methylamine, N -Vinylbenzyl-N, N Dihexylamine, N-vinylbenzyl-N-octadecyl-N-methylamine, N-vinylbenzyl-N′-methyl-piperazine, N-vinylbenzyl-N ′-(2-hydroxyethyl) -piperazine, N-benzyl- Examples thereof include N-methylaminoethyl (meth) acrylate and N, N-dibenzylaminoethyl (meth) acrylate.
Among these, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-diethylaminopropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, and N, N-diethylaminopropyl (meth) acrylamide are more preferable, Furthermore, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, and N, N-dimethylaminopropyl (meth) acrylamide are particularly preferable.

  As the oil-soluble polymer compound, a polarized compound is desirable, and among the above, a polymer having a nitrogen-containing heterocycle, a polymer having an onium group, and a polymer having an amino group are preferable, and more preferably, a polarization It is at least 1 sort (s) selected from the group which consists of the polymer which has a nitrogen-containing heterocyclic ring which has, the polymer which has onium group, and the polymer which has an amino group.

The weight average molecular weight of the oil-soluble polymer compound is preferably 1,000 or more and 50,000 or less, and more preferably 2,000 or more and 30,000 or less.
The measurement of a weight average molecular weight is a value measured by GPC (gel permeation chromatography) method. Specifically, using gel permeation chromatography (SCL-6B; manufactured by Shimadzu Corporation), Shodex-KF804 was used as a GPC column, and the solvent (tetrahydrofuran) was added at 0.8 ml / min at 40 ° C. While flowing at a flow rate, 15 μl of a sample having a concentration of 8 mg / ml (sample) / 20 ml (tetrahydrofuran) was injected and measured using polystyrene as a standard substance.

  The amount of the oil-soluble polymer compound added depends on the components of the ink A and the ink B, but from the viewpoint that the effect of the present invention is exhibited and the viscosity does not become too high, the total solid of the ink C 0.1-15 mass% is preferable with respect to a minute (mass), 0.5-10 mass% is more preferable, and 1-5 mass% is especially preferable. When the content is within the range, it is effective for preventing the dispersion of the droplets of the ink A. When the content is out of the range, the viscosity becomes high, and for example, the ejection property when using an inkjet head is hindered. There is.

  Further, the oil-soluble polymer compound may be contained in the ink A other than the ink C and optionally the ink B. When the oil-soluble polymer compound is contained in the ink A (and optionally the ink B), the content of the oil-soluble polymer compound in the ink is preferably 0.1 to 10% by mass, and 0.5 to 5% by mass. % Is more preferable. Particularly preferably, the ink A and the ink B do not substantially contain an oil-soluble polymer compound.

-Polymer having nitrogen-containing heterocycle-
Even if the polymer having a nitrogen-containing heterocyclic ring is a homopolymer only of a monomer having a nitrogen-containing heterocyclic group, a copolymer of a monomer having a nitrogen-containing heterocyclic group and another monomer It may be. In the constitution of the polymer having a nitrogen-containing heterocyclic ring, the monomer having a nitrogen-containing heterocyclic group is preferably 10 mol% or more, and more preferably 20 mol% or more.

Here, specific examples of the nitrogen-containing heterocycle include saturated heterocycles (for example, aziridine, azetidine, pyrrolidine, piperidine, piperazine, morpholine, thiomorpholine, caprolactam, valerolactam), and unsaturated heterocycles ( Examples thereof include imidazole, pyridine, pyrrole, pyrazole, pyrazine, pyrimidine, indole, purine, quinoline, and triazine.
These nitrogen-containing heterocycles may further have a substituent, and examples of the substituent include an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a halogen atom, a hydroxyl group, a carbamoyl group, and an amino group. It is done.

  The polymer having a nitrogen-containing heterocycle is preferably a polymer obtained from a vinyl monomer having a nitrogen-containing heterocycle. Specifically, N-vinylpyrrolidone, N-vinylcaprolactam, acryloylmorpholine, acryloylthiomorpholine, N-vinylimidazole, 2-methyl-1-vinylimidazole, 2-vinylpyridine, 4-vinylpyridine, N-vinylcarbazole N-methylmaleimide, N-ethylmaleimide, 2-isopropenyl-2-oxazoline and the like. Of these, N-vinylimidazole, 2-vinylpyridine, and 4-vinylpyridine are particularly preferable.

  Furthermore, the polymer having a nitrogen-containing heterocycle may be a copolymer of the monomer and a monomer copolymerizable therewith. Examples of the copolymerizable monomer include (meth) acrylic acid alkyl esters [for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, ( N-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) (Meth) acrylic acid alkyl (carbon number 1 to 18) ester such as lauryl acrylate and stearyl (meth) acrylate], (meth) acrylic acid cycloalkyl ester [(meth) acrylic acid cyclohexyl etc.], (meth) Acrylic acid aryl ester [phenyl (meth) acrylate, etc.], aralkyl ester (Meth) acrylic acid benzyl etc.], substituted (meth) acrylic acid alkyl esters [eg (meth) acrylic acid 2-hydroxyethyl etc.], (meth) acrylamides [eg (meth) acrylamide, dimethyl (meth) acrylamide Etc.], aromatic vinyls [styrene, vinyl toluene, α-methyl styrene, etc.], vinyl esters [vinyl acetate, vinyl propionate, vinyl versatate, etc.], allyl esters [eg, allyl acetate], halogen-containing single amount Examples thereof include vinyl [vinylidene chloride, vinyl chloride and the like], vinyl cyanide [(meth) acrylonitrile and the like], olefins [ethylene, propylene and the like] and the like.

  Among these copolymerizable monomers, (meth) acrylic acid alkyl esters, (meth) acrylamides, and aromatic vinyls are preferable, methyl (meth) acrylate, ethyl (meth) acrylate, (meth) ) Propyl acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate Particularly preferred are 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and styrene.

In the structure of the polymer having a nitrogen-containing heterocyclic ring, the monomer having a nitrogen-containing heterocyclic group is preferably 10 mol% or more and 100 mol% or less, and more preferably 20 mol% or more and 100 mol% or less. It is more preferable.
These polymers can be synthesized by radical (co) polymerization of the monomers. As the radical polymerization, known methods such as bulk polymerization, solution polymerization, and emulsion polymerization can be used. Further, if necessary, a polymerization initiation catalyst known to those skilled in the art can be used.

  Furthermore, a polymer having a nitrogen-containing heterocycle may be obtained by polycondensation. 2,4-dichlorotriazine (for example, 2,4-dichloro-6-butylamino-1,3,5-triazine) and diamine (for example, N, N′-dimethylethylenediamine, N, N′-dimethylhexamethylenediamine, N, N′-dibutylhexamethylenediamine, N, N′-dioctylhexamethylenediamine, etc.) or a polycondensation obtained by polycondensation of piperazine and a dicarboxylic acid (for example, adipic acid) ester. A coalescence can also be mentioned.

Specific examples of the polymer having a preferable nitrogen-containing heterocycle include the following.

Furthermore, the following polymers can also be mentioned as preferable specific examples.

~ Polymer having onium group ~
The polymer having an onium group may be a homopolymer of only a monomer having an onium group, or may be a copolymer of a monomer having an onium group and another monomer. In the constitution of the polymer having an onium group, the monomer having an onium group is preferably 10 mol% or more, and more preferably 20 mol% or more.
Examples of the onium group include an ammonium group, a phosphonium group, and a sulfonium group, and an ammonium group is preferable. The polymer having an ammonium group can be obtained as a homopolymer of a monomer having a quaternary ammonium base, a copolymer of the monomer and another monomer, or a condensation polymer.

  In the present invention, the polymer having an ammonium group is particularly preferably a polymer having at least one unit represented by the following general formula (1) or (2).

In the above formula, R represents a hydrogen atom or a methyl group, and R ^{21 to} R ²³ and R ^{25 to} R ²⁷ each independently represents an alkyl group, an aralkyl group, or an aryl group. R ²⁴ represents an alkylene group, an aralkylene group, or an arylene group. Y represents O or NR ′, and R ′ represents a hydrogen atom or an alkyl group. X ⁻ represents a counter anion.

The alkyl group represented by R ^{21 to} R ²³ and R ^{25 to} R ²⁷ preferably has 18 or less carbon atoms, more preferably 16 or less carbon atoms, and particularly preferably 12 or less carbon atoms. The alkyl group may be linear or cyclic, and may have a substituent. Examples of the substituent include an alkoxy group, an aryloxy group, a halogen atom, a hydroxyl group, a carbamoyl group, and an amino group.
Specific examples of the (substituted) alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, n-hexyl group, cyclohexyl group, and 2-ethylhexyl group. N-octyl group, n-nonyl group, n-decyl group, n-dodecyl group, n-octadecyl group, hydroxyethyl group, 1-hydroxypropyl group, N, N-dimethylaminoethyl group, methoxyethyl group, chloroethyl Groups and the like.
Among these alkyl groups, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, n-hexyl group, cyclohexyl group, 2-ethylhexyl group, n-octyl group , N-nonyl group and n-decyl group are preferable, and methyl group, ethyl group, n-propyl group, n-butyl group and n-hexyl group are particularly preferable.

The aryl group represented by R ^{21 to} R ²³ and R ^{25 to} R ²⁷ preferably has 18 or less carbon atoms, more preferably 16 or less carbon atoms, and particularly preferably 12 or less carbon atoms. The aryl group may have a substituent, and examples of the substituent include an alkyl group, an alkoxy group, an aryloxy group, a halogen atom, a hydroxyl group, a carbamoyl group, a cyano group, and an amino group.
Specific examples of the (substituted) aryl group include phenyl group, alkylphenyl group (for example, methylphenyl group, ethylphenyl group, n-propylphenyl group, n-butylphenyl group, cumenyl group, mesityl group, tolyl group, Xylyl group, etc.), naphthyl group, chlorophenyl group, dichlorophenyl group, trichlorophenyl group, bromophenyl group, hydroxyphenyl group, methoxyphenyl group, acetoxyphenyl group, cyanophenyl group and the like.
Among these (substituted) aryl groups, a phenyl group and a naphthyl group are particularly preferable.

The aralkyl group represented by R ^{21 to} R ²³ and R ^{25 to} R ²⁷ preferably has 18 or less carbon atoms, more preferably 16 or less carbon atoms, and particularly preferably 12 or less carbon atoms. Examples of the alkyl part of the aralkyl group include the above-described alkyl group, and examples of the aryl part of the aralkyl group include the aryl group as described above. The alkyl part and / or aryl part of the aralkyl group may have a substituent, and the substituent is the same as the substituents exemplified for the alkyl group and aryl group.
Specific examples of the (substituted) aralkyl group include a benzyl group, a phenylethyl group, a vinylbenzyl group, a hydroxyphenylmethyl group, a diphenylmethyl group, a trityl group, and a styryl group.
Of these (substituted) aralkyl groups, a benzyl group is particularly preferred.

R ^{21 to} R ²³ and R ^{25 to} R ²⁷ are particularly preferably each independently an alkyl group or an aralkyl group, and among them, a methyl group, an ethyl group, a hexyl group, and a benzyl group are preferable.

R ²⁴ represents a divalent linking group, preferably an alkylene group, an aralkylene group, or an arylene group.
The alkylene group represented by R ²⁴ preferably has 8 or less carbon atoms, more preferably 6 or less carbon atoms, and particularly preferably 4 or less carbon atoms. The alkylene group may be linear or cyclic and may have a substituent. Examples of the substituent include an alkoxy group, an aryloxy group, a halogen atom, a hydroxyl group, and a carbamoyl group. And amino groups.
Specific examples of the (substituted) alkylene group include methylene group, ethylene group, propylene group, trimethylene group, tetramethylene group, hexamethylene group, octamethylene group, 2-hydroxyethylene group, 2-hydroxypropylene group, 2- A methoxypropylene group etc. are mentioned.
Of these (substituted) alkylene groups, a methylene group, an ethylene group, a propylene group, a trimethylene group, and a 2-hydroxypropylene group are particularly preferable.

The arylene group represented by R ²⁴ preferably has 12 or less carbon atoms, more preferably 10 or less carbon atoms, and particularly preferably 8 or less carbon atoms. The arylene group may have a substituent, and the substituent is the same as the substituent exemplified for the aryl group.
Specific examples of the (substituted) arylene group include a phenylene group, an alkylphenylene group (for example, 2-ethyl-1,4-phenylene group, 2-propyl-1,4-phenylene group, etc.), 2-chloro-1 , 4-phenylene group, alkoxyphenylene group (for example, 2-methoxy-1,4-phenylene group, etc.), among which phenylene group is particularly preferable.

The aralkylene group represented by R ²⁴ preferably has 12 or less carbon atoms, more preferably 10 or less carbon atoms, and particularly preferably 8 or less carbon atoms. Examples of the alkyl portion of the aralkylene group include the alkyl groups as described above, and examples of the aryl portion of the aralkylene group include the aryl group as described above. The aralkylene group may have a substituent, and the substituent is the same as the substituent exemplified in the alkyl group and aryl group.
Specific examples of the (substituted) aralkylene group include a xylylene group and a benzylidene group, and a benzylidene group is particularly preferable.

R ²⁴ is particularly preferably an alkylene group, and among them, an ethylene group or a propylene group is preferable.

The alkyl group represented by R ′ is preferably the same as the alkyl groups represented by R ^{21 to} R ²³ and R ^{25 to} R ²⁷ . The same applies to preferred embodiments.

Y is particularly preferably —O— or —NH—.
X ⁻ is a counter anion, halogen ion (Cl ⁻ , Br ⁻ , I ⁻ ), sulfonate ion, alkyl sulfonate ion, aryl sulfonate ion, alkyl carboxylate ion, aryl carboxylate ion, PF ₆ ⁻ , BF _4- ^{and the} like can be mentioned. Of these, Cl ⁻ , Br ⁻ , toluenesulfonic acid ions, methanesulfonic acid ions, PF ₆ ⁻ and BF ₄ ⁻ are particularly preferable.

  In the case of a polymer having at least one unit represented by the general formula (1) or (2), the unit represented by the general formula (1) or (2) is 10 to 100 mol% in the polymer. It is preferable to contain, and the case where it contains 20-100 mol% is more preferable.

  Preferable specific examples of the polymer having at least one of the units represented by the general formula (1) or (2) include the following polymers.

  Examples of the polymer having an onium group according to the present invention other than the polymer having at least one unit represented by the general formula (1) or (2) include epichlorohydrin-dimethylamine addition polymerization. Products, dihalide compounds (eg, xylylene dichloride, xylylene dibromide, 1,6-dibromohexane) and diamines (N, N, N ′, N′-tetramethylethylenediamine, N, N, N ′, N′-tetra) Methyl hexamethylenediamine, N, N′-dimethylpiperazine, diazabicyclooctane) addition polymerization products, and the like.

Further, polymers having amino groups (for example, polyallylamine, polyvinylamine, polyethyleneimine, polydiallylamine, poly (N-methyldiallylamine), poly (N-ethyldiallylamine), diisocyanates (for example, hexamethylene diisocyanate, isophorone diisocyanate) , Toluene diisocyanate, xylylene diisocyanate) and a diol having a tertiary amino group (for example, a polyadduct of N-methyldiethanolamine, N-ethyldiethanolamine, N, N′-3-hydroxypropylpiperazine, etc.)) , Ethyl chloride, methyl bromide, ethyl bromide, methyl iodide, ethyl iodide, dimethyl sulfate, diethyl sulfate, methyl p-toluenesulfonate, p-toluene It can also be obtained by adding ethyl sulfonate.
Among these, preferred examples include the following specific examples.

  The polymer having at least one of the units represented by the general formula (1) or (2) is a homopolymer of a monomer having the following ammonium group or a copolymer containing the monomer: Obtainable.

  Examples of the monomer having an ammonium group include trimethyl-p-vinylbenzylammonium chloride, trimethyl-m-vinylbenzylammonium chloride, triethyl-p-vinylbenzylammonium chloride, triethyl-m-vinylbenzylammonium chloride, N , N-dimethyl-N-ethyl-Np-vinylbenzylammonium chloride, N, N-diethyl-N-methyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-Nn-propyl-N -P-vinylbenzylammonium chloride, N, N-dimethyl-Nn-octyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N-benzyl-Np-vinylbenzylammonium chloride, N, N Diethyl-N-benzyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N- (4-methyl) benzyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N-phenyl-N -P-vinylbenzylammonium chloride, trimethyl-p-vinylbenzylammonium bromide, trimethyl-m-vinylbenzylammonium bromide, trimethyl-p-vinylbenzylammonium sulfonate, trimethyl-m-vinylbenzylammonium sulfonate, trimethyl-p-vinylbenzyl Ammonium acetate, trimethyl-m-vinylbenzylammonium acetate, N, N, N-triethyl-N-2- (4-vinylphenyl) ethylammonium chloride, N, N, N- Liethyl-N-2- (3-vinylphenyl) ethylammonium chloride, N, N-diethyl-N-methyl-N-2- (4-vinylphenyl) ethylammonium chloride, N, N-diethyl-N-methyl- N-2- (4-vinylphenyl) ethylammonium acetate, trimethyl-2- (methacryloyloxy) ethylammonium chloride, triethyl-2- (methacryloyloxy) ethylammonium chloride, trimethyl-2- (acryloyloxy) ethylammonium chloride, Triethyl-2- (acryloyloxy) ethylammonium chloride, trimethyl-3- (methacryloyloxy) propylammonium chloride, triethyl-3- (methacryloyloxy) propylammonium chloride Trimethyl-2- (methacryloylamino) ethylammonium chloride, triethyl-2- (methacryloylamino) ethylammonium chloride, trimethyl-2- (acryloylamino) ethylammonium chloride, triethyl-2- (acryloylamino) ethylammonium chloride, Trimethyl-3- (methacryloylamino) propylammonium chloride, triethyl-3- (methacryloylamino) propylammonium chloride, trimethyl-3- (acryloylamino) propylammonium chloride, triethyl-3- (acryloylamino) propylammonium chloride, N, N-dimethyl-N-ethyl-2- (methacryloyloxy) ethylammonium chloride, N, N-die -N-methyl-2- (methacryloyloxy) ethylammonium chloride, N, N-dimethyl-N-ethyl-3- (acryloylamino) propylammonium chloride, trimethyl-2- (methacryloyloxy) ethylammonium bromide, trimethyl-3 -(Acryloylamino) propylammonium bromide, trimethyl-2- (methacryloyloxy) ethylammonium sulfonate, trimethyl-3- (acryloylamino) propylammonium acetate, monomethyldiallylammonium chloride, dimethyldiallylammonium chloride, allylamine hydrochloride, etc. Can do.

Examples of monomers copolymerizable with these monomers include (meth) acrylic acid alkyl esters [for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, (meth ) Isopropyl acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, (meth) acrylic acid 2 -(Meth) acrylic acid C1-18 alkyl ester such as ethylhexyl, (meth) acrylic acid lauryl, stearyl (meth) acrylate], (meth) acrylic acid cycloalkyl ester [(meth) acrylic acid cyclohexyl etc.], ( (Meth) acrylic acid aryl esters [phenyl (meth) acrylate etc.], aralkyl Steal [benzyl (meth) acrylate, etc.], substituted (meth) acrylic acid alkyl ester [eg, 2-hydroxyethyl (meth) acrylate, etc.], (meth) acrylamides [eg, (meth) acrylamide, dimethyl (meth) ) Acrylamide, etc.], aromatic vinyls [styrene, vinyl toluene, α-methyl styrene, etc.], vinyl esters [vinyl acetate, vinyl propionate, vinyl versatate, etc.], allyl esters [eg, allyl acetate], halogen-containing Monomers [vinylidene chloride, vinyl chloride, etc.], vinyl cyanides [(meth) acrylonitrile, etc.], olefins [ethylene, propylene, etc.] and the like.
Among these copolymerizable monomers, (meth) acrylic acid alkyl esters, (meth) acrylamides, and aromatic vinyls are preferable, methyl (meth) acrylate, ethyl (meth) acrylate, (meth) ) Propyl acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate Particularly preferred are 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and styrene.

  These polymers can be synthesized by radical (co) polymerization of the monomers. As the radical polymerization, known methods such as bulk polymerization, solution polymerization, and emulsion polymerization can be used. Further, if necessary, a polymerization initiation catalyst known to those skilled in the art can be used.

~ Polymer having amino group ~
The polymer having an amino group may be a homopolymer only of a monomer having an amino group, or may be a copolymer of a monomer having an amino group and another monomer. In the polymer having an amino group, the monomer having an amino group is preferably 10 mol% or more and 100 mol% or less, and more preferably 20 mol% or more and 100 mol% or less.
Examples of the monomer having an amino group include N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, and N, N-diethylamino. Propyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-diethylaminopropyl (meth) Acrylamide, diallylamine, N-methyldiallylamine, N-vinylbenzyl-N, N-dimethylamine, N-vinylbenzyl-N, N-diethylamine, N-vinylbenzyl-N-ethyl-N-methylamine, N-vinylbenzyl -N, N-dihexyl N-vinylbenzyl-N-octadecyl-N-methylamine, N-vinylbenzyl-N′-methyl-piperazine, N-vinylbenzyl-N ′-(2-hydroxyethyl) -piperazine, N-benzyl-N -Methylaminoethyl (meth) acrylate, N, N-dibenzylaminoethyl (meth) acrylate and the like.
Among these, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-diethylaminopropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, and N, N-diethylaminopropyl (meth) acrylamide are more preferable, Furthermore, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, and N, N-dimethylaminopropyl (meth) acrylamide are particularly preferable.

Examples of monomers copolymerizable with these monomers include (meth) acrylic acid alkyl esters [for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, (meth ) Isopropyl acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, (meth) acrylic acid 2 -(Meth) acrylic acid alkyl ester having 1 to 18 carbon atoms in the alkyl moiety, such as ethylhexyl, lauryl (meth) acrylate, stearyl (meth) acrylate, etc.], (meth) acrylic acid cycloalkyl ester [( Meth) acrylic acid cyclohexyl etc.], (meth) acrylic acid aryl ester [(meth) acrylic Phenyl etc.], (meth) acrylic acid aralkyl esters [(meth) benzyl benzyl etc.], substituted (meth) acrylic acid alkyl esters [eg (meth) acrylic acid 2-hydroxyethyl etc.], (meth) acrylamides [ For example, (meth) acrylamide, dimethyl (meth) acrylamide, etc.], aromatic vinyl [styrene, vinyl toluene, α-methylstyrene, etc.], vinyl esters [vinyl acetate, vinyl propionate, vinyl versatate, etc.], allyl Examples include esters [such as allyl acetate], halogen-containing monomers [such as vinylidene chloride and vinyl chloride], vinyl cyanides [such as (meth) acrylonitrile], and olefins [such as ethylene and propylene].
Among these copolymerizable monomers, alkyl (meth) acrylate having an alkyl group having 1 to 8 carbon atoms, benzyl (meth) acrylate, and styrene are preferable, ethyl (meth) acrylate, ( Particularly preferred are propyl (meth) acrylate, n-butyl (meth) acrylate, n-hexyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate.

Furthermore, other polymers having an amino group include polyallylamine, polyvinylamine, polyethyleneimine, polydiallylamine, poly (N-methyldiallylamine), poly (N-ethyldiallylamine), and modified products thereof (polyallylamine Benzyl chloride adducts, phenylglycidyl ether adducts, acrylonitrile adducts), diisocyanates (eg hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, xylylene diisocyanate) and diols having tertiary amino groups (eg N-methyldiethanolamine) , N-ethyldiethanolamine, N, N′-3-hydroxypropylpiperazine) and the like.
Among these, polyallylamine, polyvinylamine, polyethyleneimine, and modified products thereof are more preferable, and further, a modified product of polyallylamine is particularly preferable.

  In the present invention, the polymer having an amino group is particularly preferably a polymer having a unit represented by the following general formula (3).

In the general formula (3), R ¹¹ represents hydrogen or a methyl group, Y represents O or NR ¹⁵ , R ¹⁵ represents hydrogen or an alkyl group, R ¹² represents a divalent linking group, R ¹³ And R ¹⁴ each independently represents an alkyl group, an aralkyl group or an aryl group.
R ¹¹ is more preferably hydrogen, Y is more preferably O or NH, further preferably O, R ¹³ and R ¹⁴ are more preferably alkyl groups or aralkyl groups, and further preferably alkyl groups. .

The divalent linking group represented by R ¹² is preferably an alkylene group or an arylene group, and more preferably an alkylene group.
Specific examples of the divalent linking group include methylene group, ethylene group, propylene group, trimethylene group, tetramethylene group, hexamethylene group, octamethylene group, phenylene group, 2-hydroxypropylene group, etc. Among these, an ethylene group, a propylene group, and a trimethylene group are particularly preferable.

The alkyl group represented by R ¹³ , R ¹⁴ or R ¹⁵ is preferably an alkyl group having 18 or less carbon atoms, more preferably an alkyl group having 12 or less carbon atoms, and particularly preferably an alkyl group having 8 or less carbon atoms. The alkyl group may be linear or cyclic, and may have a substituent. Examples of the substituent include a hydroxy group, an alkoxy group (for example, a methoxy group, an ethoxy group, Propoxy group etc.), aryloxy group (eg phenoxy group etc.), amino group, carbamoyl group, halogen atom and the like.
Specific examples of the (substituted) alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, n-hexyl group, cyclohexyl group, 2-ethylhexyl group. Group, n-octyl group, n-nonyl group, n-decyl group, n-dodecyl group, n-octadecyl group, hydroxyethyl group, 1-hydroxypropyl group, N, N-dimethylaminoethyl group, methoxyethyl group, A chloroethyl group etc. are mentioned. Among these, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, n-hexyl group, cyclohexyl group, 2-ethylhexyl group, n-octyl group, n -Nonyl group and n-decyl group are more preferable, and methyl group, ethyl group, n-propyl group, n-butyl group and n-hexyl group are particularly preferable.

The aryl group represented by R ¹³ or R ¹⁴ is preferably an aryl group having 18 or less carbon atoms, more preferably an aryl group having 16 or less carbon atoms, and particularly preferably an aryl group having 12 or less carbon atoms. The aryl group may have a substituent.
Specific examples of the (substituted) aryl group include phenyl group, alkylphenyl group (for example, methylphenyl group, ethylphenyl group, n-propylphenyl group, n-butylphenyl group, cumenyl group, mesityl group, tolyl group, Xylyl group, etc.), naphthyl group, chlorophenyl group, dichlorophenyl group, trichlorophenyl group, bromophenyl group, hydroxyphenyl group, methoxyphenyl group, acetoxyphenyl group, cyanophenyl group, etc., among which phenyl group, naphthyl group Is particularly preferred.

The aralkyl group represented by R ¹³ or R ¹⁴ is preferably an aralkyl group having 18 or less carbon atoms, more preferably an aralkyl group having 16 or less carbon atoms, and particularly preferably an aralkyl group having 12 or less carbon atoms. Examples of the alkyl part of the aralkyl group include the above-described alkyl group, and examples of the aryl part of the aralkyl group include the aryl group as described above. The aralkyl group may have a substituent.
Specific examples of the (substituted) aralkyl group include a benzyl group, a phenylethyl group, a vinylbenzyl group, a hydroxyphenylmethyl group, a diphenylmethyl group, a trityl group, and a styryl group. Among these, a benzyl group is particularly preferable. preferable.

  Preferable specific examples of the polymer having a unit represented by the general formula (3) include the following polymers.

  Preferred polymers other than the polymer having an amino group according to the present invention and having a unit represented by the general formula (3) include the following polymers.

  The polymer having the unit represented by the general formula (3) can be synthesized using radical (co) polymerization. Examples of the radical (co) polymerization include bulk polymerization, solution polymerization, and emulsion polymerization. A known method such as the above can be used. In addition, it is not limited to this method, Other well-known methods can also be employ | adopted.

  As described above, from the viewpoint of containing an oil-soluble polymer compound in the ink C, the ink C is preferably prepared to be oily, and in this case, a high-boiling organic solvent is preferably used as the solvent. It is preferable that a water-soluble solvent is not included substantially.

In the present invention, as a preferred form,
(1) Ink A contains a colorant and a polymerizable or crosslinkable material, Ink B contains no colorant, contains a polymerizable or crosslinkable material, and Ink C contains a high-boiling organic solvent and a polymerization initiator. Form (2) Ink A contains a colorant and a polymerizable or crosslinkable material, Ink B contains no colorant, contains a polymerizable or crosslinkable material, and Ink C contains a high-boiling organic solvent and an oil-soluble polymer Form containing compound and polymerization initiator (3) Ink A contains a colorant and a polymerizable or crosslinkable material, Ink B contains no colorant, contains a polymerizable or crosslinkable material, and ink C is polymerized (4) Ink A contains a colorant and a polymerizable or crosslinkable material, Ink B contains no colorant, contains a polymerizable or crosslinkable material, Ink C is polymerizable or crosslinkable (5) Ink A contains a colorant and a polymerizable or crosslinkable material, and Ink B contains no colorant and contains a polymerizable or crosslinkable material. Ink C includes a high boiling point organic solvent, a polymerizable or crosslinkable material, and a polymerization initiator (6) Ink A includes a colorant and a polymerizable or crosslinkable material, and Ink B includes a colorant Examples thereof include a polymerizable or crosslinkable material, and the ink C includes a high-boiling organic solvent, a polymerizable or crosslinkable material, an oil-soluble polymer compound, and a polymerization initiator. More preferred is the above (1) or (2), and further preferred is the above (2).
In the above, the polymerizable or crosslinkable material is contained in the ink A and the ink B, and may be contained in the ink C. The polymerization initiator is contained in the ink C, and the ink A and the ink B. It may be contained in.

<Other ingredients>
In addition to the components described above, known additives can be used in combination according to the purpose.
~ Storage stabilizer ~
A storage stabilizer can be added to the ink A, the ink B, and the ink C according to the present invention for the purpose of suppressing undesired polymerization during storage. The storage stabilizer is preferably used in the presence of a polymerizable or crosslinkable material, and it is preferable to use a storage stabilizer that is soluble in the contained droplets or liquid, or other coexisting components.

  Storage stabilizers include quaternary ammonium salts, hydroxyamines, cyclic amides, nitriles, substituted ureas, heterocyclic compounds, organic acids, hydroquinones, hydroquinone monoethers, organic phosphines, copper compounds, and the like. Specific examples include benzyltrimethylammonium chloride, diethylhydroxylamine, benzothiazole, 4-amino-2,2,6,6-tetramethylpiperidine, citric acid, hydroquinone monomethyl ether, hydroquinone monobutyl ether, and copper naphthenate. It is done.

  The amount of storage stabilizer added is preferably adjusted as appropriate based on the activity of the polymerization initiator, the polymerizability of the polymerizable or crosslinkable material, and the type of storage stabilizer, but the balance between storage stability and curability is balanced. In terms of solid content in the liquid, 0.005 to 1% by mass is preferable, 0.01 to 0.5% by mass is more preferable, and 0.01 to 0.2% by mass is even more preferable.

~ Conductive salts ~
Conductive salts are solid compounds that improve conductivity. In the present invention, it is preferable not to use it substantially because there is a great concern of precipitation during storage, but it is possible to increase the solubility of conductive salts or use a highly soluble liquid component. If it is good, an appropriate amount may be added.
Examples of the conductive salts include potassium thiocyanate, lithium nitrate, ammonium thiocyanate, dimethylamine hydrochloride and the like.

~solvent~
In the present invention, a solvent other than the high-boiling organic solvent described above can be used. The solvent can be used for the purpose of improving the polarity and viscosity of liquid (ink), surface tension, solubility and dispersibility of coloring materials, adjusting conductivity, and adjusting printing performance.
Note that the solvent is a water-insoluble liquid and does not contain an aqueous solvent because it is preferable in terms of recording a high-quality image with quick drying and uniform line width. The configuration used is desirable.

  A low boiling point organic solvent that is an organic solvent at 100 ° C. or lower is also exemplified, but there is a concern that the curability is affected, and it is desirable not to use the low boiling point organic solvent in consideration of environmental pollution. When used, it is preferable to use a highly safe solvent, and a highly safe solvent is a solvent having a high management concentration (an index indicated by the work environment evaluation criteria), preferably 100 ppm or more, More preferably, it is 200 ppm or more. Specific examples include alcohols, ketones, esters, ethers, hydrocarbons, and the like, and specific examples include methanol, 2-butanol, acetone, methyl ethyl ketone, ethyl acetate, and tetrahydrofuran.

  Solvents can be used in combination other than one kind alone, but when water and / or a low-boiling organic solvent is used, the amount of both used is preferably 0 to 20% by mass in each solution. 10 mass% is still more preferable, and it is preferable not to contain substantially. When water is contained in the ink A, the ink B, and the ink C according to the present invention, the stability over time such as non-uniformity over time, turbidity of the liquid due to dye precipitation, etc., and non-permeability or This is not preferable in terms of dryness when a slow-penetrating recording medium is used. In addition, it does not contain substantially means accepting presence of an inevitable impurity.

~ Other additives ~
Furthermore, known additives such as polymers, surface tension adjusters, ultraviolet absorbers, antioxidants, anti-fading agents and pH adjusters can be used in combination.
Regarding the surface tension adjusting agent, ultraviolet absorber, antioxidant, anti-fading agent, and pH adjusting agent, known compounds may be appropriately selected and used. For example, JP-A-2001-181549 discloses a specific example. The additives described can be used.

In addition to the above, the ink A, the ink B, and the ink C according to the present invention can be separately contained in the ink A, the ink B, and the ink C according to the present invention. The set of compounds has a feature of rapidly forming aggregates or rapidly thickening the liquid, thereby more effectively suppressing coalescence between adjacent droplets. Can do.
Examples of the reaction of the set of compounds include an acid / base reaction, a hydrogen bonding reaction with a carboxylic acid / amide group-containing compound, a crosslinking reaction represented by boronic acid / diol, and a reaction by electrostatic interaction with a cation / anion. Etc.

-Recording medium-
In the inkjet recording method of the present invention, any of a permeable recording medium, a non-permeable recording medium, and a slowly permeable recording medium can be used as a recording medium. Among these, a non-permeable or slowly permeable recording medium is preferable from the viewpoint of more remarkable effects of the present invention.

  When an image is recorded on a recording medium with low liquid absorbency, conventionally, adjacent droplets (ink A and ink B) applied so as to overlap each other stay on the medium and come into contact before drying. And the image blur and color mixing, the line width of the fine line is non-uniform, and the end non-uniformity due to the bulging of the end of the image tends to occur, but the SP value of ink C with ink A and ink B The difference between the inks is 10 or less, and the ink B is applied to the non-image forming area where the image is not formed with the ink A. When the droplets of B are applied so as to overlap each other, coalescence between the droplets is suppressed and the spread of the colored ink A is suppressed. Therefore, the fine line in the image formed by droplet ejection Width variation, distortion of grid lines, It is possible to effectively prevent uneven due to the image end portion is inflated. As a result, it is possible to record a high-quality image with no blur and fine line quality (including line width uniformity) and a uniform edge of the image. In addition, there is no stickiness and excellent scratch resistance.

  Here, the permeable recording medium is a medium in which when a 10 pl (picoliter) droplet is dropped on the recording medium, the time until the entire liquid amount permeates is 100 milliseconds or less. Examples of the paper include plain paper and porous paper. The non-permeable recording medium refers to a medium in which droplets do not substantially permeate, and examples thereof include a medium using synthetic resin or glass. “Substantially does not penetrate” means that the penetration rate of a droplet after 1 minute is 5% or less. Further, the slow-penetrating recording medium refers to a medium in which when a 10 pl droplet is dropped onto a recording medium, the time until the total liquid permeates is 100 ms or more. For example, paper. Details of the non-permeable or slowly permeable recording medium will be described later.

Examples of the permeable recording medium include plain paper, porous paper, and other media that can absorb liquid.
Examples of the non-permeable or slowly permeable recording medium include art paper, synthetic resin, rubber, resin-coated paper, glass, metal, earthenware, and wood. In addition, for the purpose of adding a function, a base material obtained by combining a plurality of these materials can be used.

  As the synthetic resin, any synthetic resin can be used. For example, polyesters such as polyethylene terephthalate and polybutadiene terephthalate, polyolefins such as polyvinyl chloride, polystyrene, polyethylene, polyurethane, and polypropylene, acrylic resins, polycarbonates, and acrylonitrile-butadiene. -Styrene copolymer etc., Diacetate, Triacetate, Polyimide, Cellophane, Celluloid etc. are mentioned. When the synthetic resin is used, the thickness and shape may be any of a film shape, a card shape, and a block shape, and are not particularly limited, and may be either transparent or opaque.

  The synthetic resin is preferably used in the form of a film used for so-called soft packaging, and various non-absorbable plastics and films thereof can be used. Examples of the plastic film include a PET film, an OPS film, an OPP film, a PNy film, a PVC film, a PE film, and a TAC film. Other plastics that can be used include polycarbonate, acrylic resin, ABS, polyacetal, PVA, and rubbers.

  Examples of the resin-coated paper include a transparent polyester film, an opaque polyester film, an opaque polyolefin resin film, and a paper support in which both sides of paper are laminated with a polyolefin resin. Particularly preferred is a paper support in which both sides of the paper are laminated with a polyolefin resin.

  There is no restriction | limiting in particular as said metal, For example, aluminum, iron, gold | metal | money, silver, copper, nickel, titanium, chromium, molybdenum, silicon | silicone, lead, zinc etc., or stainless steel etc., and these composite materials are suitable. .

  Further, a read-only optical disk such as a CD-ROM or DVD-ROM, a write-once optical disk such as a CD-R or DVD-R, a rewritable optical disk, or the like can also be used. And a gloss-imparting layer.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof.

Example 1
<Preparation of pigment dispersion>
16 g of PB15: 3 (IRGALITE BLUE GLO; manufactured by Ciba Specialty Chemicals), 48 g of 1,6-hexanediol diacrylate (HDDA; manufactured by Daicel Cytec Co., Ltd.), and 16 g of BYK-168 (manufactured by BYK Chemie) And stirred with a stirrer for 1 hour. The mixture after stirring was dispersed with an Eiger mill to obtain pigment dispersion P-1.
Here, dispersion conditions were such that zirconia beads having a diameter of 0.65 mm were filled at a filling rate of 70%, the peripheral speed was 9 m / s, and the dispersion time was 1 hour.

<Preparation of Ink Liquid I-1 for Inkjet Recording Containing Pigment>
Inks for inkjet recording I-1 (ink A) were prepared by stirring and mixing the components having the following composition. The SP value of the ink liquid I-1 for ink jet recording was 20.
-Pigment dispersion P-1 ... 10 g
DPCA60 (Nippon Kayaku Co., Ltd .; polymerizable compound) 0.54 g
・ 1,6 hexanediol diacrylate (polymerizable compound) ... 9.46g
(HDDA; manufactured by Daicel Cytec Co., Ltd.)

  As described above, the SP value was calculated by the SP value calculation program by R.L.smith (Tohoku University) (25 ° C.). The same applies hereinafter. However, the compound containing no carbon atom was excluded from the calculation, and the structural unit such as a polymer or polyethylene chain was a saturated repeating unit having a bond, and water was calculated as 47.8.

<Preparation of colorless ink-jet recording ink II-1>
Ink liquid II-1 (colorless ink B) for ink jet recording was prepared by stirring and mixing the components having the following composition. The SP value of the ink liquid II-1 for ink jet recording was 20.
DPCA60 (Nippon Kayaku Co., Ltd .; polymerizable compound) 0.54 g
・ 1,6 hexanediol diacrylate (polymerizable compound) ... 19.46g
(HDDA; manufactured by Daicel Cytec Co., Ltd.)

<Preparation of ink liquid III-1 for inkjet recording>
Inks for ink jet recording III-1 (ink C) were prepared by stirring, mixing and dissolving the components having the following composition. The SP value of the ink liquid III-1 for ink jet recording is shown in Table 1 below.
・ High boiling point organic solvent (Exemplary Compound S-101 below) ... 17.4g
・ The following polymerization initiator-1 (TPO-L) 2.6 g

<Preparation of inkjet recording ink liquids III-2 to III-7>
In the preparation of the ink liquid III-1 for ink jet recording, as shown in Table 1 below, an oil-soluble polymer compound was further added to 0.34 g with respect to 20 g of the whole liquid, and III-6, III- As for No. 7, inkjet recording ink liquids III-2 to III-7 were prepared in the same manner as the inkjet recording ink liquid III-1, except that the kind of the high-boiling organic solvent was changed. The SP values of liquids III-1 to III-7 are shown in Table 1 below.

<Preparation of Comparative Ink Liquid III-00 for Comparison>
Components of the following composition were mixed with stirring and dissolved to prepare Comparative Ink Liquid III-00. The SP value of Comparative Ink Liquid III-00 was 38.
・ Glycerin ... 17.4g
・ Polymerization initiator-1 (TPO-L) 2.6 g

<Preparation of Comparative Ink Liquid I-01 for Comparison>
Components of the following composition were mixed with stirring and dissolved to prepare Comparative Ink Liquid I-01. The SP value of Comparative Ink Liquid I-01 was 44 (Because the pigment was not dissolved, it was excluded from the calculation of the SP value).
-Aqueous pigment dispersion-PB15: 3 ... 10.5 g
・ Styrene / acrylic polymer: 3.15 g
・ N-methylpyrrolidone: 5g
・ Isopropyl alcohol: 5g
・ Water: 76.3g

<Preparation of Comparative Ink Liquid II-01 for Comparison>
Components of the following composition were mixed with stirring and dissolved to prepare Comparative Ink Liquid II-01. The SP value of Comparative Ink Liquid II-01 was 45.
・ Styrene / acrylic polymer: 3.15 g
・ N-methylpyrrolidone: 5g
・ Isopropyl alcohol: 5g
・ Water: 86.8g

<Preparation of Comparative Ink Liquid III-01 for Comparison>
Components of the following composition were mixed with stirring and dissolved to prepare Comparative Ink Liquid III-01. The SP value of Comparative Ink Liquid III-01 was 38.
・ A-TMPT-3EO (manufactured by Shin-Nakamura Chemical Co., Ltd.) ... 10g
・ Water: 60g
・ Isopropyl alcohol: 30 g

<Image recording and evaluation>
An experimental jig equipped with a head CB1 (nozzle number 318, nozzle density 150 npi, drop size 6 pl, drive frequency, 4.8 kHz) manufactured by TOSHIBA TEC CO., LTD. Was prepared, and the ink liquids I-1 and II for ink jet recording obtained from the above were prepared. -1, III-1 were loaded into this experimental jig.

  Next, the inkjet recording ink liquid III-1 is first ejected in a solid shape from the head, and then the inkjet recording ink liquid I-1 is ejected in a line shape to form a 1 mm square image non-formation region. A grid-like image was formed as described above. Thereafter, an ink liquid II-1 for ink jet recording was further ejected onto a 1 mm square image non-formation region and coated.

  At this time, as a recording medium, a polyethylene terephthalate (PET) sheet having a thickness of 60 μm (trade name: PPL / Xerox film for laser printers, OHP FILM, manufactured by Fuji Xerox Co., Ltd .; hereinafter referred to as PET sheet), and art paper. (Brand name: Tokishi Art Both sides, Mitsubishi Paper Industries Co., Ltd.) was used.

  The ink jet recording ink is adjusted by adjusting the head moving speed and the angle with respect to the investigation direction, and for the ink jet recording liquid III-1, the overlapping rate of adjacent liquid droplets is 5%. For the liquids I-1 and II-1, the overlapping intervals of adjacent liquid droplets are set to 50%, and the ink liquid III-1 for ink jet recording and the ink liquids I-1 and II- for ink jet recording are used. 1 and the droplet ejection interval between the ink liquids I-1 and II-1 for ink jet recording were 400 milliseconds.

  As described above, the overlapping rate is 100 (2b-c) / 2b [%], where b is the radius of the droplet after 1 second after droplet ejection and c is the interval between adjacent droplets. Calculated.

  Further, as a comparative example, similarly to the above, the inkjet recording ink liquid III-1 was ejected in a solid shape from the head, and the inkjet recording ink liquid I-1 was ejected in a line shape on the inkjet recording ink liquid III-1 to form a 1 mm square. A grid-like image was formed so as to form a non-image forming area (non-image portion). Thereafter, ink jet recording ink liquid II-1 was not ejected.

  Further, the liquid III-1 used in the above was replaced with the ink liquids III-2 to III-7 for ink jet recording obtained from the above or the comparative ink liquid III-00 (comparative example), and in the same manner as in the above Discharged.

  As a comparative example, the inkjet recording liquids I-1, II-1, and III-1 were ejected in a grid pattern in the same manner as described above, instead of the comparative ink liquids I-01, II-01, and III-01.

After 1 second had elapsed from the end of ejection (droplet ejection) of the ink liquid for ink jet recording, an image was recorded by irradiating with a metal halide lamp at a wavelength of 365 nm with an ultraviolet ray amount of ˜500 mJ / cm ² . The following evaluation was performed about the obtained image. The evaluation results are shown in Table 2 below. For each of the liquids prepared above, the liquid “I-” is liquid I (ink A), the liquid “II-” is liquid II (ink B), and the liquid “III-” is liquid III (ink C). ).

-1. Evaluation of line quality
The image obtained from the above was visually observed, and the quality of the line was evaluated according to the following evaluation criteria.
<Evaluation criteria>
A: The dot shape was maintained and a uniform line shape was obtained.
A ′: The dot shape is not maintained, but a uniform line shape is obtained.
B: There was no independence of each dot, and disturbance of the line width due to coalescence between adjacent droplets was observed in some places.
C: There was no independence of each dot, and disturbance of the line width due to coalescence between adjacent droplets as a whole was recognized.

-2. Evaluation of lattice distortion
The lattice-like image was observed with a microscope, and the shape of the lattice was evaluated according to the following evaluation criteria.
<Evaluation criteria>
A: A 1 mm square grid could be reproduced.
B: Almost no distortion of the 1 mm square lattice was observed.
C: The lattice was distorted, and the non-image portion in the lattice was narrowed to 90% or less.
D: The lattice was distorted, and the non-image area in the lattice was narrowed to about 50% or less.

-3. Swelling of image edge
The end of the line in the lattice-shaped image formed by droplet ejection was observed with a microscope and evaluated according to the following evaluation criteria.
<Evaluation criteria>
A: The edge was almost the same thickness as the center.
B: The edge part slightly spread from the center part.
C: The edge part was 10% or more thicker than the center part.

-4. Evaluation of stickiness −
Immediately after UV irradiation, the image surface (recording surface) was touched with a finger and evaluated according to the following evaluation criteria.
<Evaluation criteria>
A: There was no stickiness.
B: Some stickiness was recognized.
C: Significant stickiness was recognized.

-5. Evaluation of scratch resistance
The PET sheet and art paper on which a lattice-like image was recorded were observed for changes when the image was rubbed 10 times with an eraser after 30 minutes had passed after UV irradiation, and evaluated according to the following evaluation criteria.
<Evaluation criteria>
A: There was no decrease in density due to abrasion.
B: A slight decrease in density due to rubbing was observed.
C: The concentration was remarkably reduced by rubbing.

-6. Evaluation of light resistance
A PET sheet on which a lattice image is recorded is irradiated with xenon light (85,000 Lux) for 1 week using a weather meter (Atlas C.I65), and the density before and after irradiation is measured with a microdensitometer (model name). : MICRO-PHOTOMETER MPM-No. 172, manufacturer name: manufactured by Union Optical Co., Ltd.) to obtain a dye residual ratio [%], and evaluated in 5 stages according to the following evaluation criteria. The light resistance was evaluated only for the image on the PET sheet.
<Evaluation criteria>
A: The pigment residual ratio was 90% or more.
B: Dye remaining rate was 89-80%.
C: The pigment residual ratio was 79 to 70%.
D: Dye residual ratio was 69 to 50%.
E: Dye remaining rate was less than 49%.

-7. Evaluation of ozone resistance
A PET sheet on which a lattice-like image is recorded is stored for 1 week under an ozone concentration of 5.0 ppm, and the density of the image before and after storage is measured using a microdensitometer (model name: MICRO-PHOTOMETER MPM-No. 172, manufacturer Name: Union Optical Co., Ltd.) to obtain a dye residual ratio (%), and evaluated in five stages according to the following evaluation criteria. The ozone resistance was evaluated only for the image on the PET sheet.
<Evaluation criteria>
A: The pigment residual ratio was 90% or more.
B: Dye remaining rate was 89-80%.
C: The pigment residual ratio was 79 to 70%.
D: Dye residual ratio was 69 to 50%.
E: Dye remaining rate was less than 49%.

As shown in Table 2, in the present invention in which the II liquid (ink B), which is a transparent ink, is ejected between the grids made of the I liquid, the occurrence of grid distortion and image edge bulge can be suppressed. A sharp high-quality image was obtained. In addition, when an oil-soluble polymer compound was contained in the II liquid (transparent ink), it was effective in preventing the occurrence of lattice distortion and image edge swelling.
On the other hand, in the comparative example not using the II liquid, although the stickiness and scratching properties were good and the line quality was excellent, the distortion of the lattice and the swelling of the edge of the image occurred, and the sharp high-quality image was It was not obtained. In addition, even when II liquid (transparent ink) is used, the comparative example that does not satisfy the SP value range in the present invention is inferior in stickiness and scratching, etc., as well as line quality, lattice distortion, and image edge swelling. None of them were inferior.

Claims (5)

Onto the recording medium, and an ink A containing a coloring agent and a polymerizable or crosslinkable material, and the ink B is a polymerizable or crosslinkable material content of unrealized pigment at most 1 mass%, the ink A and the An ink jet recording method for forming an image using an ink C having a difference in SP value of 2 or less from each of the inks B,
At least before the ink A is deposited, the ink C is applied to the same area as the image formed with the ink A on the recording medium or to an area wider than the image, and then the applied ink C is applied. The ink A is ejected in an image-like manner on the surface to form an image, and the ink B is ejected onto an image non-formation area of the recording medium to cover at least a part of the image non-formation area. An inkjet recording method characterized by the above. The inkjet recording method according to claim 1, wherein at least the ink C includes an organic solvent having a boiling point of 100 ° C. or higher and / or an oil-soluble polymer compound. The ink C-jet recording method according to claim 1 or 2 including at least the polymerizable or polymerization initiator a crosslinkable material to polymerization reaction or crosslinking reaction. After firing droplets of the ink A and the ink B to form the desired image, either by applying an active energy to the image of the claims 1 to 3 for polymerizing or crosslinking the polymerizable or crosslinkable material 1 The inkjet recording method according to item. The recording medium is non-permeable recording medium or claim 1 any one of the 4 Zen'ekiryou when dropping a droplet of 10pl is the recording medium described above 100m seconds time to penetrate The ink jet recording method described in 1.