JP2007276387A - Ink media set and pretreatment liquid cartridge, ink cartridge, ink recording object, inkjet recording method, and inkjet recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink media set and a pretreatment liquid cartridge, an ink cartridge, an ink recording object, an inkjet recording method, and an inkjet recording device by which clear high quality images similar to printed matters can be obtained without problem in drying speed in smooth printing sheets with low water absorbing capacity. <P>SOLUTION: The ink media set is constituted by having, inks including at least coloring agents, water dispersible resins and water, media for printing having at least a coated layer on a supporting body, and a pretreatment liquid provided to the recording faces of the media for printing during inkjet recording, the total content of coloring agents and the water dispersible resins in the ink is 10 to 35% by mass, the content of the water dispersible resin relative to the total content is 70 to 95% by mass, the pretreatment liquid contains 10 to 80% by mass of an ink fixing auxiliary agent as a solid content lowering at least one of the dispersibility and the solubility of the ink and has viscosity of 100 to 10,000 mPa s at 25°C. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ink media set including an ink capable of recording a high-quality image by an ink jet recording method, a recording medium, and a pretreatment liquid, and a pretreatment liquid cartridge and an ink cartridge using the ink media set. The present invention relates to an ink record, an ink jet recording method, and an ink jet recording apparatus.

  The ink jet recording method is a method of performing printing by causing small droplets of ink to fly and adhere to a recording medium such as paper. As the ink used in this ink jet recording method, generally, a colorant of various dyes or pigments is dissolved or dispersed in water or water and a wetting agent. Such a wetting agent contributes to prevention of drying of the nozzle due to its water retention capacity. However, when printing on paper having a high penetration rate, for example, plain paper, the wetting agent is difficult to evaporate, so that there is a drawback in that the back-through increases.

  Therefore, in order to solve such a problem, a white pigment is applied to a recording medium or a surface on which a material for fixing a dye in the ink is applied in advance when an image is formed on the surface of the recording medium such as plain paper. And recording media coated with a water-soluble polymer have been proposed (see, for example, Patent Document 1, Patent Document 2, Patent Document 3, Patent Document 4, Patent Document 5, etc.). These proposals are recording media that have undergone special processing and correspond to general recording media such as plain paper. Patent Document 6 discloses in advance carboxymethylcellulose, polyvinyl alcohol, polyvinyl acetate on a recording medium. An ink jet recording method has been proposed in which a polymer solution such as the above is ejected and then ink is ejected onto a portion where the polymer solution is adhered to perform printing. However, in these polymer solutions, feathering was not suppressed and water resistance was not improved.

  In addition, an ink jet recording in which a pretreatment liquid for a recording medium containing a compound that insolubilizes the dye in the ink is deposited on the recording medium by an ink jet method, and then the ink is ejected and printed on a portion of the recording medium to which the pretreatment liquid has adhered. Methods have been proposed (see Patent Document 7, Patent Document 8, Patent Document 9, etc.). However, in these methods as well, in order to stably eject the pretreatment liquid, it is necessary to lower the viscosity of the pretreatment liquid. For this reason, the concentration of the compound that insolubilizes the dye has to be reduced. In order to obtain a sufficient image quality improvement effect with such a pretreatment liquid, it is necessary to apply a relatively large amount of the pretreatment liquid. Therefore, curling and cockling of the recording medium are likely to occur. Furthermore, there is a problem that the amount of moisture adhering at the two-color overlapping portion is large, and not only cockling but also ink penetration is large.

  Also proposed is an image forming method in which a colorless liquid composition containing at least a silicone compound such as silicone oil and a cationic compound is applied to a recording medium, and then a recording ink containing an anionic component is adhered by an inkjet recording method. (See Patent Document 10). However, in this proposal, the area where the silicone compound adheres has extremely low ink permeability, so the drying of the image area is slow, and when high-speed printing is performed by this image forming method, in addition to low penetration, the recording medium becomes wet. There is a problem that the image quality is remarkably deteriorated, for example, the adjacent dots are coalesced and the white lines are generated in the solid image portion along the head main scanning direction. In addition, the colorless liquid composition has a problem that when it is stored for a long period of time, the silicone oil is decomposed or phase separation occurs, and stable recording characteristics cannot be obtained.

  Further, after applying a colorless or light-colored image recording promoting liquid containing a colorant and a compound that insolubilizes the colorant in the ink composed of a solvent for dispersing or dissolving the colorant to the recording medium, the ink is There has been proposed an image recording method in which an image recording promoting liquid contains a predetermined surfactant that is ejected as droplets and attached to a recording medium (see Patent Document 11). According to this method, since the surfactant in the image recording promoting liquid improves the permeability and wettability, the drying property of the image is improved, and high-speed recording can be supported. However, there are cases where the penetration of the coloring material into the paper by the surfactant is promoted, and further improvement has been demanded from the fear of an increase in see-through, a decrease in image density, and occurrence of feathering.

On the other hand, when an image is recorded with water-based inkjet ink on paper with a small water absorption capacity such as coated paper for general printing such as art paper, gloss paper, etc., the wetting agent does not easily evaporate, so it takes a lot of time for drying. Is not practical. Furthermore, since the ink absorbency is slow, bleeding and beading occurred on the paper surface.
Therefore, it is desirable to provide an ink jet recording method that is quick to dry even on printing paper as described above, has high image density and saturation, has high image quality on plain paper, and does not clog nozzles even when stopped for a long time. It is rare.

For example, Patent Document 12 proposes an inkjet ink in which the content of a wetting agent is extremely reduced. According to this proposal, even if plain paper is used, high image density image quality without any showthrough can be obtained. However, in this proposal, since the resin is not contained in the ink, the fixability of the image is inferior particularly when the pigment ink is used. Further, there is no disclosure or suggestion about an improvement in drying speed when printing on offset coated paper.
Patent Document 13 proposes a quick-drying dye ink. However, in this proposed embodiment, the wetting agent is contained in a large amount of 15% by mass or more, no resin is added, and the paper is made of high-quality paper. Not in.
Further, Patent Document 14 proposes an aqueous precoat liquid that can form a good inkjet image on a water repellent surface such as a plastic substrate, or on the surface of an oil-based ink layer such as an offset printed matter or a gravure printed matter. However, this proposed ink is limited to pigment ink and cannot be applied to dye ink, and since the precoat liquid is applied by an ink jet method, there are various restrictions on the liquid formulation to ensure ejection reliability. .
Patent Document 15 proposes a combination of a fixer and an ink as an ink jet printing system for improving the quality of an image printed on an offset medium. However, since the proposed fixing liquid is also attached using an inkjet head, the fixing agent liquid formulation is subject to various restrictions to ensure the same ejection reliability as ink.
Patent Document 16 proposes a recording paper for both ink jet recording and electrophotographic transfer paper in which the critical surface tension of the recording layer using amorphous silica is used without using an alkaline earth metal salt. However, this proposal cannot ensure the quality of an inkjet image for a recording layer containing pigments such as kaolin, talc, and calcium carbonate used for inexpensive and widely distributed printing paper.

  Accordingly, even on a smooth printing paper having a low water absorption capacity, there is no problem in the drying speed, and an ink media set that provides a clear and close-to-print image, a pretreatment liquid cartridge using the ink media set, an ink cartridge, As for the ink recorded matter, the ink jet recording method, and the ink jet recording apparatus, there are currently no products having sufficiently satisfactory performance.

JP-A-56-86789 JP-A-55-144172 Japanese Patent Laid-Open No. 55-81992 JP 52-53012 A JP-A-56-89594 JP-A-56-89595 JP-A-64-63185 JP-A-8-20159 Japanese Patent Laid-Open No. 8-20161 JP-A-8-142500 JP-A-10-250216 JP 2004-115551 A JP 60-34992 A JP 2004-74432 A JP 2004-181955 A Japanese Patent No. 3150569

  An object of the present invention is to solve various problems in the prior art and achieve the following objects. That is, the present invention relates to a smooth printing paper having a low water absorption capacity, an ink capable of obtaining a clear and high-quality image close to printed matter, a recording medium, and a pretreatment liquid. It is an object of the present invention to provide an ink media set, and a pretreatment liquid cartridge, an ink cartridge, an ink recorded matter, an ink jet recording method, and an ink jet recording apparatus using the ink media set.

Means for solving the above problems are as follows. That is,
<1> an ink containing at least a colorant, a water-dispersible resin, and water;
A recording medium having a support and at least a coating layer on the support;
A pretreatment liquid applied to the recording surface of the recording medium during inkjet recording, and an ink media set having
The total content of the colorant and the water-dispersible resin in the ink is 10 to 35% by mass, and the content of the water-dispersible resin with respect to the total content is 70 to 95% by mass,
The pretreatment liquid contains 10 to 80% by mass of an ink fixing assistant that reduces at least one of ink dispersibility and solubility, and has a viscosity at 25 ° C. of 100 to 10,000 mPa · s. There is an ink media set characterized by being.
<2> The ink media set according to <1>, wherein the ink fixing aid is a cationic compound.
<3> The ink media set according to <2>, wherein the cationic compound is a cationic polymer.
<4> The ink media set according to <3>, wherein the cationic polymer is at least one selected from polymers represented by the following structural formulas (1) to (20).
However, in said structural formula (1), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. R represents an alkylene group having 1 to 3 carbon atoms. n represents the number of polymerizations.
However, in said structural formula (2), n represents the number of polymerization.
However, in the structural formula (3), X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. R ₁ represents either a hydrogen atom or CH ₃ . R ₂ , R ₃ , and R ₄ may be the same as or different from each other, and represent either a hydrogen atom or an alkyl group. n represents the number of polymerizations.
However, in said structural formula (4), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (5), n represents the natural number of 5-30.
However, in said structural formula (6), n represents the number of polymerization.
However, in the structural formula (7), X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (8), n represents the number of polymerization.
However, the structural formula (9), Z and Y each represent -OCOCH ₃ or -OH. R ₅ represents an alkylene group having 1 to 4 carbon atoms. n, l, and m each represent the number of polymerizations.
However, in the structural formula (10), R ₆ represents an alkyl group. X ⁻ represents an anion selected from a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in the structural formula (11), R ⁷ and R ⁸ may be the same as or different from each other, and represent either a hydrogen atom or an alkyl group. X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (12), X < ^- > represents the anion in any one of a halogen ion, nitrate ion, nitrite ion, and acetate ion. n represents the number of polymerizations.
However, in said structural formula (13), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (14), j and k represent a natural number of 2-6, respectively. n represents the number of polymerizations.
However, in the structural formula (15), X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (16), X < ^- > represents the anion in any one of a halogen ion, nitrate ion, nitrite ion, and acetate ion. Q represents a copolymerizable monomer component. n and m each represent the number of polymerizations.
However, in said structural formula (17), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (18), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in the structural formulas (19) and (20), D ¹ represents a substituent represented by any of the following structural formulas (21) and (22). D ² is independent of D ¹ and represents any one of a hydrogen atom, the following structural formula (21), and the following structural formula (22). n represents a natural number, and m represents an integer of 0 or more.
However, in the structural formula (21) and the structural formula (22), R ₉ and R ₁₀ may be the same as or different from each other, and are either a hydrogen atom, an alkyl group, or an aryl group. Represents. R ₁₁ and R ₁₂ may be the same as or different from each other, and each represents a hydrogen atom, an alkali metal, or a substituent represented by the following structural formula (23).
However, in the structural formula (23), R _{13 to} R ₁₆ may be the same as or different from each other, and are any of a hydrogen atom, an alkyl group, an aryl group, a hydroxyalkyl group, and a benzyl group. Represents
<5> The ink media set according to <2>, wherein the cationic compound is particles and is dispersed in the pretreatment liquid.
<6> The ink media set according to <5>, wherein the particles are cationic silica particles.
<7> The ink media set according to any one of <5> to <6>, wherein the cationic compound is a cationic emulsion.
<8> The ink media set according to <1>, wherein the ink fixing aid is a water-soluble polyvalent metal salt.
<9> The ink media set according to any one of <1> to <8>, wherein a critical surface tension based on JIS K6768 on the recording surface of the recording medium is 25 to 40 mN / m.
<10> Pure water recording medium having a transfer amount of pure water to a recording surface of ² to 35 ml / m ² at a contact time of 100 ms measured with a dynamic scanning absorption meter and a contact time of 400 ms. The ink media set according to any one of <1> to <9>, wherein the amount of transfer to the recording surface is 3 to 40 ml / m ² .
<11> The ink according to any one of <1> to <10>, wherein the coating layer in the recording medium contains a pigment, and the pigment is at least one selected from kaolin, talc, and calcium carbonate. Media set.
<12> The ink media set according to any one of <1> to <11>, wherein the colorant in the ink is an anionic dye.
<13> Any one of <1> to <12>, wherein the water dispersible resin includes resin fine particles, the resin fine particles are acrylic silicone resin fine particles, and the glass transition temperature of the acrylic silicone resin is 25 ° C. or lower. It is an ink media set as described in above.
<14> The ink media set according to <13>, wherein the volume average particle diameter of the resin fine particles in the resin emulsion is 10 to 1,000 nm.
<15> An ink cartridge comprising the ink in the ink media set according to any one of <1> to <14>, contained in a container.
<16> A pretreatment liquid cartridge, wherein the pretreatment liquid in the ink media set according to any one of <1> to <14> is contained in a container.
<17> An inkjet recording method using the ink media set according to any one of <1> to <14>,
Applying a pretreatment liquid to the recording surface of the recording medium;
And applying a stimulus to the ink according to an image signal before the pretreatment liquid dries, and causing the ink to fly to record an image on a recording medium.
<18> The inkjet recording method according to <17>, wherein the pretreatment liquid is applied by a roller.
<19> The inkjet recording method according to any one of <17> to <18>, wherein the adhesion amount of the pretreatment liquid is 0.5 to 10 g / m ² in solid content on the recording surface of the recording medium. .
<20> The inkjet recording method according to any one of <17> to <19>, wherein the stimulus is at least one selected from heat, pressure, vibration, and light.
<21> An inkjet recording apparatus using the ink media set according to any one of <1> to <14>,
Means for applying a pretreatment liquid to the recording surface of the recording medium;
An ink jet recording apparatus comprising: means for applying a stimulus to ink according to an image signal before the pretreatment liquid dries, and causing the ink to fly to record an image on a recording medium.
<22> The inkjet recording apparatus according to <21>, wherein the stimulus is at least one selected from heat, pressure, vibration, and light.
<23> Using the ink media set according to any one of <1> to <14>, and having an image formed using ink on a recording medium provided with a pretreatment liquid. It is an ink recorded matter.

The ink media set of the present invention includes a recording medium having at least a colorant, a water-dispersible resin, and water, a recording medium having at least a coating layer on a support, and a recording surface of the recording medium during inkjet recording. And a pretreatment liquid to be applied. The pretreatment liquid is applied to the recording surface of the recording medium during ink jet recording, and the pretreatment liquid contains 10 to 80 mass in terms of solid content of an ink fixing aid that reduces at least one of ink dispersibility and solubility. %, And the viscosity at 25 ° C. is 100 to 10,000 mPa · s. In the pretreatment liquid, a compound that lowers the solubility and dispersibility of the ink is contained at a high concentration, and a pretreatment liquid having a higher viscosity than the conventional one is applied to the recording medium. Compared with the method applied by the ink jet recording method, the effect of preventing color bleeding, feathering and ink back-through is great, and the image density and color tone are improved. In particular, because of its high viscosity, the pretreatment liquid does not penetrate deep inside the recording medium, such as plain paper, and stays in the vicinity of the surface of the recording medium. Even when the amount of pretreatment liquid applied per unit area is small, the above-described effect of improving the image quality can be obtained, and the liquid application amount is small, so that the recording medium is hardly cocked. Furthermore, by using an anionic ink and a cationic pretreatment liquid, the effect of preventing the ink from coming through can be enhanced, and the image quality can be further improved.
Further, since the total content of the colorant and the water-dispersible resin in the ink is 10 to 35% by mass, and the content of the water-dispersible resin with respect to the total content is 70 to 95% by mass, Can be prevented, the image density is high, and the saturation of the image can be improved.

The inkjet recording method of the present invention uses the ink media set of the present invention,
Applying a pretreatment liquid to the recording surface of the recording medium;
Before the treatment liquid dries, applying a stimulus to the ink in accordance with an image signal and causing the ink to fly to record an image on a recording medium. As a result, a smooth printing paper having a low water absorption capability has no problem with the drying speed, and a clear and high-quality image close to the printed matter is possible.

The ink jet recording apparatus of the present invention uses the ink media set of the present invention,
Means for applying a pretreatment liquid to the recording surface of the recording medium;
A means for applying a stimulus to the ink in accordance with an image signal before the treatment liquid dries, and causing the ink to fly to record an image on a recording medium. As a result, a smooth printing paper having a low water absorption capability has no problem in drying speed, and a clear and high-quality image close to printed matter can be formed.

  According to the present invention, an ink that can solve conventional problems, has a low water-absorbing ability, has a problem in drying speed, and can obtain a clear and high-quality image close to a printed matter, and recording. An ink media set composed of a recording medium and a pretreatment liquid, and a pretreatment liquid cartridge, an ink cartridge, an ink recorded matter, an ink jet recording method, and an ink jet recording apparatus using the ink media set can be provided.

(Ink media set)
The ink media set of the present invention includes ink, a recording medium, and a pretreatment liquid, and further includes other configurations as necessary.

<Ink>
The ink contains at least a colorant, a water-dispersible resin, and water, and further contains a wetting agent, a penetrating agent, a surfactant, and, if necessary, other components.

-Colorant-
As the colorant, any of pigments and dyes can be used, and these can be used in combination. Currently, anionic dyes or pigments are used in general inkjet inks. In the present invention, the composition of the ink used is not limited, but it is used in combination with a commonly used ink using an anionic coloring material and a pretreatment liquid containing a cationic compound. The most effective.
The anionic component in the ink is at least one colorant selected from an anionic dye, a pigment or dye dispersed with an anionic dispersant, a pigment having an anionic group, and anionic colored fine particles. Since the colorant has an anionic group as a functional group, or the anionic component is adsorbed to the colorant, the coloring component in the ink is changed by the reaction between the anionic component and the cationic resin. It is possible to efficiently stay on the surface layer of the recording medium, and various image quality improvement effects such as image density improvement, back-through density reduction, feathering, and border blurring are obtained. Among these, in particular, when an anionic dye is used, the dye is fixed in the vicinity of the media surface due to the effect of the pretreatment liquid, and therefore, it can be suitably used.

<Pigment>
There is no restriction | limiting in particular as said pigment, According to the objective, it can select suitably, Any of an inorganic pigment and an organic pigment may be sufficient. You may use these pigments in mixture of multiple types.
Examples of the organic pigment include azo, phthalocyanine, anthraquinone, quinacridone, dioxazine, indigo, thioindigo, perylene, isoindolenone, aniline black, azomethine, rhodamine B lake, and carbon black. Can be mentioned.
Examples of the inorganic pigment include iron oxide, titanium oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, bitumen, cadmium red, chrome yellow, and metal powder.

  The particle diameter of these pigments is preferably 0.01 to 0.30 μm. If the particle diameter is less than 0.01 μm, the particle diameter approaches that of the dye, so that light resistance and feathering may deteriorate. If it exceeds 0.30 μm, clogging of the discharge port or filter in the printer Clogging may occur, and ejection stability may not be obtained.

There is no restriction | limiting in particular as a color of the said pigment, According to the objective, it can select suitably, For example, the thing for black, the thing for color, etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together.
Examples of the black color include carbon black (CI pigment black 7) such as furnace black, lamp black, acetylene black, channel black, copper, iron (CI pigment black 11), oxidation, and the like. Examples thereof include metals such as titanium, organic pigments such as aniline black (CI pigment black 1), and the like.
The carbon black used in the black pigment ink is not particularly limited and may be appropriately selected according to the purpose. However, it is carbon black produced by a furnace method or a channel method, and has a primary particle size of 15 to 40 nm. The BET method has a specific surface area of 50 to 300 m ² / g, a DBP oil absorption of 40 to 150 ml / 100 g, a volatile content of 0.5 to 10%, and a pH value of 2 to 9. As such carbon black, a commercially available product can be used. 2300, no. 900, MCF-88, no. 33, no. 40, no. 45, no. 52, MA7, MA8, MA100, no. 2200B (all manufactured by Mitsubishi Chemical Corporation); Raven700, 5750, 5250, 5000, 3500, 1255 (all manufactured by Columbia); Regal400R, 330R, 660R, MoguL, Monarch700, 800, 880, 900, 1000, 1100, 1300, Monarch 1400 (all manufactured by Cabot Corporation); Color Black FW1, FW2, FW2V, FW18, FW200, S150, S160, S170, Printex 35, U, V, 140U, 140V, Special Black 6, 5, 4A, and 4 (all manufactured by Degussa).

For the color, for yellow ink, for example, C.I. I. Pigment Yellow 1 (Fast Yellow G), 3, 12 (Disazo Yellow AAA), 13, 14, 17, 23, 24, 34, 35, 37, 42 (Yellow Iron Oxide), 53, 55, 74, 81, 83 (Disazo Yellow HR), 95, 97, 98, 100, 101, 104, 108, 109, 110, 117, 120, 128, 138, 150, 153, and the like.
For magenta, for example, C.I. I. Pigment Red 1, 2, 3, 5, 17, 22 (Brilliant First Scarlet), 23, 31, 38, 48: 2 (Permanent Red 2B (Ba)), 48: 2 (Permanent Red 2B (Ca)), 48 : 3 (Permanent Red 2B (Sr)), 48: 4 (Permanent Red 2B (Mn)), 49: 1, 52: 2, 53: 1, 57: 1 (Brilliant Carmine 6B), 60: 1, 63: 1, 63: 2, 64: 1, 81 (Rhodamine 6G Lake), 83, 88, 92, 101 (Bengara), 104, 105, 106, 108 (Cadmium Red), 112, 114, 122 (Dimethylquinacridone), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 185, 190, 193, 209, 2 9, and the like.
For cyan, for example, C.I. I. Pigment Blue 1, 2, 15 (copper phthalocyanine blue R), 15: 1, 15: 2, 15: 3 (phthalocyanine blue G), 15: 4, 15: 6 (phthalocyanine blue E), 16, 17: 1, 56, 60, 63 and the like.
In addition, as the intermediate colors for red, green and blue, C.I. I. Pigment red 177, 194, 224, C.I. I. Pigment orange 43, C.I. I. Pigment violet 3, 19, 23, 37, C.I. I. Pigment green 7, 36, and the like.

The pigments listed above can be made into ink jet inks by dispersing them in an aqueous medium using a polymer dispersant or a surfactant. As a dispersant for dispersing such organic pigment powder, a normal water-soluble resin or a water-soluble surfactant can be used.
Specific examples of water-soluble resins include styrene, styrene derivatives, vinyl naphthalene derivatives, aliphatic alcohol esters of α, β-ethylenically unsaturated carboxylic acids, acrylic acid, acrylic acid derivatives, maleic acid, maleic acid derivatives, itacon. Examples thereof include block copolymers consisting of at least two monomers selected from acids, itaconic acid derivatives, fumaric acid, fumaric acid derivatives, etc., random copolymers, or salts thereof. These water-soluble resins are alkali-soluble resins that are soluble in an aqueous solution in which a base is dissolved. Among these, those having a mass average molecular weight of 3000 to 20000 are used in an inkjet ink. This is particularly preferred because of the advantages that it can be reduced in viscosity and is easily dispersed. The simultaneous use of the polymer dispersant and the self-dispersing pigment is a preferable combination because an appropriate dot diameter can be obtained. The reason is not clear, but it is thought as follows.
By containing the polymer dispersant, the penetration into the recording paper is suppressed. On the other hand, since the aggregation of the self-dispersing pigment is suppressed by containing the polymer dispersant, the self-dispersing pigment can smoothly spread in the lateral direction. Therefore, it is considered that the dots spread widely and thinly and ideal dots can be formed.
Moreover, the following are mentioned as a specific example of the water-soluble surfactant which can be used as a dispersing agent by this invention. For example, anionic surfactants include higher fatty acid salts, alkyl sulfates, alkyl ether sulfates, alkyl ester sulfates, alkyl aryl ether sulfates, alkyl sulfonates, sulfosuccinates, alkyl allyls and alkyl naphthalene sulfonic acids. Examples thereof include salts, alkyl phosphates, polyoxyethylene alkyl ether phosphate esters, and alkyl allyl ether phosphates. Examples of the cationic surfactant include alkylamine salts, dialkylamine salts, tetraalkylammonium salts, benzalkonium salts, alkylpyridinium salts, imidazolinium salts, and the like. Furthermore, examples of the amphoteric surfactant include dimethylalkyl lauryl betaine, alkyl glycine, alkyl di (aminoethyl) glycine, imidazolinium betaine and the like. Nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene polyoxypropylene glycol, glycerin ester, sorbitan ester, sucrose ester, glycerin ester polyoxyethylene ether, sorbitan Examples thereof include polyoxyethylene ethers of esters, polyoxyethylene ethers of sorbitol esters, fatty acid alkanolamides, polyoxyethylene fatty acid amides, amine oxides, and polyoxyethylene alkylamines.

In addition, the pigment can be provided with dispersibility by coating with a resin having a hydrophilic group and encapsulating the pigment.
As a method for coating a water-insoluble pigment with an organic polymer and microencapsulating, all conventionally known methods can be used. Conventionally known methods include chemical production methods, physical production methods, physicochemical methods, mechanical production methods, and the like. Specifically, the following methods are mentioned.
(1) Interfacial polymerization method (a method in which two kinds of monomers or two kinds of reactants are dissolved separately in a dispersed phase and a continuous phase, and both substances are reacted at the interface between them to form a wall film)
(2) In-situ polymerization method (liquid or gas monomer and catalyst, or two types of reactive substances are supplied from either one of the continuous phase core particles to cause a reaction to form a wall film)
(3) Liquid-cured coating method (method of forming a wall film by insolubilizing droplets of a polymer solution containing core material particles in a liquid with a curing agent)
(4) Coacervation (phase separation) method (a method in which a polymer dispersion in which core material particles are dispersed is separated into a coacervate (concentrated phase) having a high polymer concentration and a dilute phase to form a wall membrane)
(5) In-liquid drying method (preparing a liquid in which a core substance is dispersed in a solution of a wall membrane material, placing the dispersion in a liquid in which the continuous phase of this dispersion is not miscible to form a composite emulsion, Method of forming a wall film by gradually removing the dissolved medium)
(6) Melt-dispersed cooling method (using a wall film material that melts into a liquid state and solidifies at room temperature when heated, this material is heated and liquefied, core material particles are dispersed therein, and it is cooled into fine particles. A method of forming a wall film)
(7) Air suspension coating method (powder core material particles are suspended in the air by a fluidized bed, and the wall membrane material coating solution is sprayed and mixed while suspended in the air stream to form a wall membrane. Method)
(8) Spray drying method (method of spraying the encapsulated stock solution and bringing it into contact with hot air to evaporate and dry the volatile matter to form a wall film)
(9) Acid precipitation method (by neutralizing at least part of the anionic group of the organic polymer compound containing an anionic group with a basic compound to provide water solubility and in an aqueous medium together with the colorant) After kneading, make neutral or acidic with an acidic compound, deposit organic compounds and fix them on the colorant, then neutralize and disperse)
(10) Phase inversion emulsification method (a mixture containing an anionic organic polymer having dispersibility in water and a colorant is used as an organic solvent phase, and water is added to the organic solvent phase or water The method of charging the organic solvent phase into

Examples of the organic polymers (resins) used as the material constituting the wall membrane material of the microcapsule include polyamide, polyurethane, polyester, polyurea, epoxy resin, polycarbonate, urea resin, melamine resin, phenol resin, and polysaccharide. , Gelatin, gum arabic, dextran, casein, protein, natural rubber, carboxypolymethylene, polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl acetate, polyvinyl chloride, polyvinylidene chloride, cellulose, ethyl cellulose, methyl cellulose, nitrocellulose, hydroxyethyl cellulose, acetic acid Cellulose, polyethylene, polystyrene, (meth) acrylic acid polymer or copolymer, (meth) acrylic acid ester polymer or copolymer, (meth) acrylic acid- (me ) Acrylic acid ester copolymer, styrene - (meth) acrylic acid copolymer, styrene - maleic acid copolymer, sodium alginate, fatty acids, paraffin, beeswax, water wax, hardened beef tallow, carnauba wax, and albumin.
Among these, organic polymers having an anionic group such as a carboxylic acid group or a sulfonic acid group can be used. Nonionic organic polymers include, for example, polyvinyl alcohol, polyethylene glycol monomethacrylate, polypropylene glycol monomethacrylate, methoxypolyethylene glycol monomethacrylate or their (co) polymers, and 2-oxazoline cationic ring-opening polymers. Is mentioned. In particular, a complete saponified product of polyvinyl alcohol is particularly preferred because it has low water solubility and is easily dissolved in hot water but difficult to dissolve in cold water.

  Further, the amount of the organic polymer constituting the wall membrane material of the microcapsule is preferably 1 to 20% by mass with respect to a water-insoluble colorant such as an organic pigment or carbon black. By setting the amount of the organic polymer within the above range, the content of the organic polymer in the capsule is relatively low, so that the color development of the pigment is caused by the organic polymer covering the pigment surface. It becomes possible to suppress the fall of property. If the amount of the organic polymer is less than 1% by mass, it may be difficult to exert the effect of encapsulation, and if it exceeds 20% by mass, the color developability of the pigment may be significantly reduced. In consideration of other characteristics, the amount of the organic polymer is preferably in the range of 5 to 10% by mass with respect to the water-insoluble colorant. That is, since a part of the color material is exposed without being substantially covered, it is possible to suppress a decrease in color developability, and conversely, a part of the color material is not exposed and is substantially not exposed. Since it is coated, it is possible to simultaneously exhibit the effect that the pigment is coated. Further, the number average molecular weight of the organic polymers used in the present invention is preferably 2,000 or more from the viewpoint of capsule production. Here, “substantially exposed” means not the partial exposure associated with defects such as pinholes and cracks, but a state where it is intentionally exposed.

Furthermore, if an organic pigment or self-dispersing carbon black, which is a self-dispersing pigment, is used as a colorant, the dispersibility of the pigment is improved even when the content of the organic polymer in the capsule is relatively low. Furthermore, it is more preferable because sufficient storage stability of the ink can be ensured.
It is preferable to select an organic polymer suitable for the microencapsulation method. For example, in the case of interfacial polymerization, polyester, polyamide, polyurethane, polyvinyl pyrrolidone, epoxy resin and the like are suitable. In the case of in-situ polymerization method, a polymer or copolymer of (meth) acrylic acid ester, (meth) acrylic acid- (meth) acrylic acid ester copolymer, styrene- (meth) acrylic acid copolymer Polyvinyl chloride, polyvinylidene chloride, polyamide and the like are suitable. In the case of the in-liquid curing method, sodium alginate, polyvinyl alcohol, gelatin, albumin, epoxy resin and the like are suitable. In the case of the coacervation method, gelatin, celluloses, casein and the like are suitable. Moreover, in order to obtain a fine and uniform microencapsulated pigment, it is possible to use all conventionally known encapsulation methods other than the above.
When the phase inversion method or the acid precipitation method is selected as the microencapsulation method, anionic organic polymers are used as the organic polymers constituting the wall membrane material of the microcapsules. The phase inversion method is a composite or composite of an anionic organic polymer having self-dispersibility or solubility in water and a colorant such as a self-dispersion organic pigment or self-dispersion carbon black, or a self-dispersion method. A mixture of a colorant such as a dispersible organic pigment or self-dispersing carbon black, a curing agent, and an anionic organic polymer is used as an organic solvent phase, and water is added to the organic solvent phase or the organic solvent is submerged in water. In this method, a solvent phase is introduced and microencapsulation is performed while self-dispersion (phase inversion emulsification) is performed. In the above phase inversion method, there is no problem even if an ink vehicle and additives are mixed in the organic solvent phase. In particular, it is more preferable to mix an ink liquid medium because a dispersion liquid for ink can be directly produced.

On the other hand, in the acid precipitation method, a part or all of the anionic group of the anionic group-containing organic polymer is neutralized with a basic compound, and a colorant such as a self-dispersing organic pigment or self-dispersing carbon black, A water-containing cake obtained by a production method comprising a step of kneading in an aqueous medium and a step of neutralizing and acidifying an acidic compound to precipitate an anionic group-containing organic polymer and fixing it to a pigment, This is a method of microencapsulation by neutralizing part or all of an anionic group using a compound. By doing in this way, the aqueous dispersion containing the anionic microencapsulated pigment which is fine and contains many pigments can be manufactured.
Examples of the solvent used for the microencapsulation as described above include alkyl alcohols such as methanol, ethanol, propanol and butanol; aromatic hydrocarbons such as benzol, toluol and xylol; methyl acetate Esters such as ethyl acetate and butyl acetate; Chlorinated hydrocarbons such as chloroform and ethylene dichloride; Ketones such as acetone and methyl isobutyl ketone; Ethers such as tetrahydrofuran and dioxane; Cellosolves such as methyl cellosolve and butyl cellosolve Etc. The microcapsules prepared by the above method are once separated from these solvents by centrifugation or filtration, and then stirred and redispersed with water and necessary solvents to obtain the desired ink. The average particle diameter of the encapsulated pigment obtained by the above method is preferably 50 to 180 nm.
By coating the resin in this way, the pigment adheres firmly to the recording medium, so that the scratching property of the ink recorded matter can be improved.

<Dye>
As the dye, those having excellent water resistance and light resistance, which are classified into acid dyes, direct dyes, basic dyes, reactive dyes, and food dyes in the color index, are used. These dyes may be used as a mixture of a plurality of types, or may be used as a mixture with other colorants such as pigments as necessary.
(A) Examples of acid dyes and food dyes include C.I. I. Acid Yellow 17, 23, 42, 44, 79, 142; C.I. I. Acid Red 1, 8, 13, 14, 18, 26, 27, 35, 37, 42, 52, 82, 87, 89, 92, 97, 106, 111, 114, 115, 134, 186, 249, 254 289; I. Acid Blue 9, 29, 45, 92, 249; I. Acid Black 1, 2, 7, 24, 26, 94; I. Food Yellow 3, 4; I. Food Red 7, 9, 14; C.I. I. Food black 1, 2 etc. are mentioned.
(B) Examples of the direct dye include C.I. I. Direct yellow 1, 12, 24, 26, 33, 44, 50, 86, 120, 132, 142, 144; I. Direct Red 1, 4, 9, 13, 17, 20, 28, 31, 39, 80, 81, 83, 89, 225, 227; I. Direct orange 26, 29, 62, 102; I. Direct Blue 1, 2, 6, 15, 22, 25, 71, 76, 79, 86, 87, 90, 98, 163, 165, 199, 202; I. Direct black 19, 22, 32, 38, 51, 56, 71, 74, 75, 77, 154, 168, 171 and the like.
(C) Examples of basic dyes include C.I. I. Basic yellow 1, 2, 11, 13, 14, 15, 19, 21, 23, 24, 25, 28, 29, 32, 36, 40, 41, 45, 49, 51, 53, 63, 64, 65 67, 70, 73, 77, 87, 91; I. Basic Red 2, 12, 13, 14, 15, 18, 22, 23, 24, 27, 29, 35, 36, 38, 39, 46, 49, 51, 52, 54, 59, 68, 69, 70 73, 78, 82, 102, 104, 109, 112; I. Basic blue 1, 3, 5, 7, 9, 21, 22, 26, 35, 41, 45, 47, 54, 62, 65, 66, 67, 69, 75, 77, 78, 89, 92, 93 , 105, 117, 120, 122, 124, 129, 137, 141, 147, 155; I. Basic black 2, 8 etc. are mentioned.
(D) Examples of reactive dyes include C.I. I. Reactive Black 3, 4, 7, 11, 12, 17; C.I. I. Reactive Yellow 1,5,11,13,14,20,21,22,25,40,47,51,55,65,67; I. Reactive Red 1, 14, 17, 25, 26, 32, 37, 44, 46, 55, 60, 66, 74, 79, 96, 97; I. Reactive blue 1, 2, 7, 14, 15, 23, 32, 35, 38, 41, 63, 80, 95 and the like.

  The content of the colorant in the ink is preferably 6 to 15% by mass, and more preferably 8 to 12% by mass. When the content is less than 6% by mass, the image density may be lowered due to a decrease in coloring power, or feathering or bleeding may be deteriorated due to a decrease in viscosity. If left unattended, the nozzles will easily dry, causing non-ejection phenomenon, the viscosity becomes too high, penetrability will decrease, and the dots will not spread, so the image density will decrease. , The image may become blurred.

-Water dispersible resin-
The water-dispersible resin is not particularly limited and may be appropriately selected depending on the intended purpose. However, resin fine particles are preferable because the amount of the water-dispersible resin added can be increased.
The resin fine particles present as a resin emulsion dispersed in water as a continuous phase are used at the time of ink production. The resin emulsion may contain a dispersant such as a surfactant as necessary.
The content of the resin fine particles as the dispersed phase component (content of resin fine particles in the resin emulsion solution: not content in the ink after production) is generally preferably 10 to 70% by mass.
The particle diameter of the resin fine particles is preferably 10 to 1,000 nm, more preferably 100 to 300 nm, particularly considering use in an ink jet recording apparatus. The volume average particle diameter is the particle diameter in the resin emulsion, but in the case of a stable ink, there is no significant difference between the particle diameter in the resin emulsion and the resin fine particle diameter in the ink. The larger the volume average particle diameter is, the more emulsion can be added. If the volume average particle size is less than 10 nm, the amount of emulsion added may not be increased, and if it exceeds 1,000 nm, the reliability may be lowered. However, it is not always possible to use an emulsion having a particle size outside this range. These are general trends regardless of the type of emulsion.
Here, the volume average particle diameter can be measured using, for example, a particle size analyzer (Microtrac Model UPA9340, manufactured by Nikkiso Co., Ltd.). Specifically, the emulsion aqueous solution is diluted within the optimum range of the signal level, and measured under the conditions of transparency-YES, provisionally Reflective Index 1.49, Partial Density 1.19, Spherical Particles-YES, medium-water. Here, the value of 50% was defined as the volume average particle size.

The resin particles in the dispersed phase are not particularly limited and can be appropriately selected depending on the purpose. For example, urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin, butadiene resin, Examples thereof include styrene-butadiene resin, vinyl chloride resin, acrylic styrene resin, acrylic silicone resin, and the like.
As said resin emulsion, what was synthesize | combined suitably may be used and a commercial item may be used.
Examples of the commercially available resin emulsion include Microgel E-1002, E-5002 (styrene-acrylic resin emulsion, manufactured by Nippon Paint Co., Ltd.), and Boncoat 4001 (acrylic resin emulsion, manufactured by Dainippon Ink & Chemicals, Inc.). ), Boncoat 5454 (styrene-acrylic resin emulsion, manufactured by Dainippon Ink & Chemicals, Inc.), SAE-1014 (styrene-acrylic resin emulsion, manufactured by Nippon Zeon Co., Ltd.), Cybinol SK-200 (acrylic resin emulsion, Seiden Chemical Co., Ltd.), Primal AC-22, AC-61 (acrylic resin emulsion, manufactured by Rohm and Haas), Nanoacryl SBCX-2821, 3689 (acrylic silicone resin emulsion, Toyo Ink Co., Ltd.) Ltd. Formula Company), # 3070 (methyl methacrylate polymer resin emulsion, manufactured by Mikuni Color Ltd.). Among these, an acrylic silicone emulsion is particularly preferable from the viewpoint of good fixability.

The glass transition temperature of the resin component in the acrylic silicone emulsion is preferably 25 ° C. or less, and more preferably 0 ° C. or less. When the glass transition temperature exceeds 25 ° C., the resin itself becomes brittle, which causes deterioration of fixability. In particular, in the case of a printing paper that is smooth and hardly absorbs water, a decrease in fixing property may appear. However, even if the glass transition temperature is 25 ° C. or higher, it cannot always be used.
The glass transition temperature can be measured using, for example, a differential scanning calorimeter (manufactured by Rigaku Corporation).
Specifically, the resin piece of the room temperature dry film of the resin emulsion aqueous solution can be obtained by raising the temperature from around −50 ° C. with a differential scanning calorimeter and determining the temperature at which the step is generated.

  The added amount of the colorant and the water-dispersible resin in the ink is such that the total content is 10 to 35% by mass, and the content of the water-dispersible resin with respect to the total content is 70 to 95% by mass. is necessary. When the total content exceeds 35% by mass, the viscosity also increases, and there is a tendency that ejection is difficult with the current ink jet recording apparatus. However, in order to prevent bleeding, it is preferable that the total content is higher. Further, if the content of the water-dispersible resin with respect to the colorant is less than 70% by mass, the saturation of the image tends to decrease, and if it exceeds 95% by mass, the image density tends to decrease.

-Wetting agent-
The wetting agent is added for the purpose of preventing clogging of the nozzles of the recording head due to drying. There is no restriction | limiting in particular as this wetting agent, According to the objective, it can select suitably, For example, at least 1 sort (s) selected from a polyol compound, a lactam compound, a urea compound, and saccharides is suitable.

Examples of the polyol compound include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,3-purpandiol, 1,3-butanediol, 1,4 butanediol, 1,5 pentanediol, Polyhydric alcohols such as 1,6 hexanediol, glycerol, 1,2,6-hexanetriol, 1,2,4-butanetriol, 1,2,3-butanetriol, petriol; ethylene glycol monoethyl ether, Ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene group Polyhydric alcohol alkyl ethers such as coal monoethyl ether; polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether; N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, Nitrogen-containing heterocyclic compounds such as 2-pyrrolidone, 1,3-dimethylimidazolidinone, ε-caprolactam; amides such as formamide, N-methylformamide, formamide, N, N-dimethylformamide; monoethanolamine, diethanolamine, Amines such as triethanolamine, monoethylamine, diethylamine, triethylamine; sulfur-containing compounds such as dimethylsulfoxide, sulfolane, thiodiethanol; propylene carbonate, ethylene carbonate, Etc. These may be used alone or in combination of two or more.
Among these, glycerin, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1 from the viewpoint of obtaining excellent effects on solubility and prevention of poor jetting characteristics due to water evaporation , 3-butanediol, 2,3-butanediol, 1,4-butanediol, 1,5-pentanediol, tetraethylene glycol, 1,6-hexanediol, 2-methyl-2,4-pentanediol, polyethylene Glycol, 1,2,4-butanetriol, 1,2,6-hexanetriol, thiodiglycol, 2-pyrrolidone, N-methyl-2-pyrrolidone and N-hydroxyethyl-2-pyrrolidone are preferred.

Examples of the lactam compound include at least one selected from 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, and ε-caprolactam.
Examples of the urea compound include at least one selected from urea, thiourea, ethylene urea, and 1,3-dimethyl-2-imidazolidinone. In general, the amount of urea added to the ink is preferably 0.5 to 50% by mass, and more preferably 1 to 20% by mass.

Examples of the saccharide include monosaccharides, disaccharides, oligosaccharides (including trisaccharides and tetrasaccharides), polysaccharides, and derivatives thereof. Among these, glucose, mannose, fructose, ribose, xylose, arabinose, galactose, maltose, cellobiose, lactose, sucrose, trehalose, and maltotriose are preferable, and maltose, sorbitol, gluconolactone, and maltose are particularly preferable.
The polysaccharide means a saccharide in a broad sense and can be used to include substances widely existing in nature such as α-cyclodextrin and cellulose.
Examples of the saccharide derivatives include reducing sugars of the saccharides (for example, sugar alcohols [wherein general formula: HOCH ₂ (CHOH) _n CH ₂ OH (where n represents an integer of 2 to 5))] , Oxidized sugars (for example, aldonic acid, uronic acid, etc.), amino acids, thioic acids, etc. Among these, sugar alcohols are particularly preferred, and examples of the sugar alcohols include maltitol, sorbit, and the like. .

  The content of the wetting agent in the ink is preferably 10 to 50% by mass, and more preferably 20 to 35% by mass. If the content is too small, the nozzle is likely to be dried and defective ejection of droplets may occur. If the content is too large, the ink viscosity is increased, and the proper viscosity range may be exceeded.

-Penetration agent-
As the penetrant, a polyol compound having 8 or more carbon atoms and a glycol ether compound are used.
If the polyol compound has less than 8 carbon atoms, sufficient penetrability cannot be obtained, and the recording medium is soiled during double-sided printing, or ink spreading on the recording medium is insufficient, resulting in poor pixel filling. Therefore, character quality and image density may be reduced.
Examples of the polyol compound having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol (solubility: 4.2% (25 ° C.)), 2,2,4-trimethyl-1,3-pentanediol. (Solubility: 2.0% (25 ° C.)) is preferable.
Examples of the glycol ether compound include polyhydric alcohol alkyls such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether. Examples of ethers include polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

  There is no restriction | limiting in particular in the addition amount of the said penetrant, According to the objective, it can select suitably, 0.1-20 mass% is preferable, and 0.5-10 mass% is more preferable.

-Surfactant-
The surfactant is not particularly limited, and can be appropriately selected from surfactants that do not impair dispersion stability depending on the purpose, depending on the combination of the type of colorant, a wetting agent, a penetrating agent, and the like. In particular, when printing on printing paper, those having low surface tension and high leveling properties are preferred, and at least one selected from silicone surfactants and fluorosurfactants is preferred. Among these, a fluorine-based surfactant is particularly preferable.

The fluorine-based surfactant preferably has 2 to 16 carbon atoms substituted by fluorine, and more preferably 4 to 16 carbon atoms. When the fluorine-substituted carbon number is less than 2, the effect of fluorine may not be obtained, and when it exceeds 16, problems such as ink storage stability may occur.
Examples of the fluorosurfactant include a perfluoroalkyl sulfonic acid compound, a perfluoroalkyl carboxylic compound, a perfluoroalkyl phosphate compound, a perfluoroalkyl ethylene oxide adduct, and a perfluoroalkyl ether group in the side chain. And the polyoxyalkylene ether polymer compound. Among these, a polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain is particularly preferable because of its low foaming property.

Examples of the perfluoroalkyl sulfonic acid compound include perfluoroalkyl sulfonic acid, perfluoroalkyl sulfonate, and the like.
Examples of the perfluoroalkyl carboxylic compounds include perfluoroalkyl carboxylic acids and perfluoroalkyl carboxylic acid salts.
Examples of the perfluoroalkyl phosphate compound include perfluoroalkyl phosphate esters, perfluoroalkyl phosphate salts, and the like.
The polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain includes a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in the side chain, and a polyoxyalkylene ether having a perfluoroalkyl ether group in the side chain. Examples thereof include a sulfate salt of a polymer and a salt of a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in the side chain.
As counter ions of salts in these fluorosurfactants, Li, Na, K, NH ₄ , NH ₃ CH ₂ CH ₂ OH, NH ₂ (CH ₂ CH ₂ OH) ₂ , NH (CH ₂ CH ₂ OH) ₃ etc. are mentioned.

As said fluorosurfactant, what was synthesize | combined suitably may be used and a commercial item may be used.
As this commercial item, for example, Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, S-145 (all manufactured by Asahi Glass Co., Ltd.), Fullrad FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431 (all manufactured by Sumitomo 3M Limited), MegaFuck F-470, F1405, F -474 (all manufactured by Dainippon Ink & Chemicals, Inc.), Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, UR (all manufactured by DuPont), FT-110 , FT-250, FT-251, FT-400S, FT-150, FT-400SW (all manufactured by Neos Co., Ltd.), PF-151 Among these, FT-110, FT-250, and FT-251 made by Neos Co., Ltd. are particularly preferable in that good printing quality, particularly color development and leveling on paper are remarkably improved. FT-400S, FT-150, FT-400SW, and OM-nova PF-151N are particularly preferable.
As specific examples of the fluorosurfactant, those represented by the following structural formula are suitable.

(1) Anionic fluorosurfactant
In the structural formula, Rf represents a mixture of fluorine-containing hydrophobic groups represented by the following structural formula. A is —SO ₃ X, —COOX, or —PO ₃ X (where X is a counter anion, specifically, a hydrogen atom, Li, Na, K, NH ₄ , NH ₃ CH ₂ CH ₂ OH, , NH ₂ (CH ₂ CH ₂ OH) ₂ , or NH (CH ₂ CH ₂ OH) ₃ ).

In the structural formula, Rf ′ represents a fluorine-containing group represented by the following structural formula. X represents the same meaning as described above. n represents an integer of 1 or 2, and m represents 2-n.
However, in said structural formula, n represents the integer of 3-10.

In the structural formula, Rf ′ and X have the same meaning as described above.

In the structural formula, Rf ′ and X have the same meaning as described above.

(2) Nonionic fluorosurfactant
However, in the structural formula, Rf represents the same meaning as described above. n represents an integer of 5 to 20.

However, in the structural formula, Rf ′ represents the same meaning as described above. n represents an integer of 1 to 40.

(3) Amphoteric fluorosurfactant
However, in the structural formula, Rf represents the same meaning as described above.

(4) Oligomer type fluorosurfactant
In the structural formula, Rf ″ represents a fluorine-containing group represented by the following structural formula. N represents an integer of 0 to 10. X represents the same meaning as described above.
However, in said structural formula, n represents the integer of 1-4.

In the structural formula, Rf ″ represents the same meaning as described above. L represents an integer of 0 to 10, m represents an integer of 0 to 10, and n represents an integer of 0 to 10, respectively.

The silicone-based surfactant is not particularly limited and may be appropriately selected depending on the purpose, and is preferably one that does not decompose even at a high pH. Examples include one-end-modified polydimethylsiloxane, side-chain both-end-modified polydimethylsiloxane, and the like. Particularly preferred.
As such a surfactant, an appropriately synthesized product or a commercially available product may be used.
Such commercially available products can be easily obtained from, for example, Big Chemie, Shin-Etsu Silicone, Toray Dow Corning Silicone, etc.

The polyether-modified silicone surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the polyalkylene oxide structure represented by the following structural formula may be represented by the side chain of Si part of dimethylpolysiloxane. And the like, and the like.
However, m, n, a, and b represent an integer in the said structural formula. R and R ′ represent an alkyl group or an alkylene group.

  A commercial item can be used as said polyether modified silicone compound, For example, KF-618, KF-642, KF643 (all are Shin-Etsu Chemical Co., Ltd. product) etc. are mentioned.

  In addition to the fluorine surfactant and the silicone surfactant, an anionic surfactant, a nonionic surfactant, an amphoteric surfactant, and the like can be used.

  Examples of the anionic surfactant include polyoxyethylene alkyl ether acetate, dodecylbenzene sulfonate, oxalate sulfonate, laurate, and polyoxyethylene alkyl ether sulfate salt.

Examples of the nonionic surfactant include acetylene glycol surfactants, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl esters, polyoxyethylene sorbitan fatty acid esters, and the like.
Examples of the acetylene glycol surfactants include 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, 3,5-dimethyl-1-hexyn-3-ol and the like can be mentioned. Examples of commercially available acetylene glycol surfactants include Surfynol 104, 82, 465, 485, and TG manufactured by Air Products (USA).

Examples of the amphoteric surfactant include lauryl aminopropionate, lauryl dimethyl betaine, stearyl dimethyl betaine, lauryl dihydroxyethyl betaine, lauryl dimethylamine oxide, myristyl dimethylamine oxide, stearyl dimethylamine oxide, dihydroxyethyl lauryl amine oxide, Polyoxyethylene coconut oil alkyldimethylamine oxide, dimethylalkyl (coconut) betaine, dimethyl lauryl betaine and the like can be mentioned.
Such surfactants are commercially available products such as Nikko Chemicals Co., Ltd., Nippon Emulsion Co., Ltd., Nippon Shokubai Co., Ltd., Toho Chemical Co., Ltd., Kao Co., Ltd., Adeka Co., Ltd., Lion Co., Ltd., Aoki Oil Co., Ltd., Sanyo Chemical It can be easily obtained from Industrial Co., Ltd.
The surfactant is not limited to these, and may be used alone or in combination. Even if it does not dissolve easily in the ink alone, it can be solubilized by mixing and exist stably.

Among these surfactants, those represented by the following structural formulas (1) to (5) are preferable.
^{_{R 1 -O- (CH 2 CH 2}} O) h -R 2 ··· structural formula (1)
However, in said structural formula (1), R < ¹ > represents the C6-C14 alkyl group which may be branched, or the C6-C14 perfluoroalkyl group which may be branched. R ² represents a hydrogen atom or an optionally branched alkyl group having 1 to 4 carbon atoms. h represents an integer of 5 to 20.

^{_{R 1 -COO- (CH 2 CH 2}} O) h -R 2 ··· structural formula (2)
However, the in the structural formula (2), R ¹ represents an alkyl group which may be branched having 6 to 14 carbon atoms. R ² represents a hydrogen atom or an optionally branched alkyl group having 1 to 4 carbon atoms. h represents an integer of 5 to 20.

In the Structural formula (3), R ³ represents a hydrocarbon group, for example, such as an alkyl group branched carbon atoms and optionally 6-14. k represents an integer of 5 to 20.

However, the structural formula (4), R ⁴ represents a hydrocarbon group, for example, an alkyl group branched carbon atoms and optionally 6-14. L represents an integer of 5 to 10, and p represents an integer of 5 to 20. The propylene glycol chain and the ethylene glycol chain may be block polymerized or randomly polymerized.

However, in said structural formula (5), q and r represent the integer of 5-20, respectively.

The content of the surfactant in the ink is preferably 0.01 to 3.0% by mass, and more preferably 0.5 to 2% by mass. However, the total content of liquid components that are liquid at 25 ° C., which has a higher boiling point than water, is 20% by mass or less, and preferably 15% by mass or less.
When the content is less than 0.01% by mass, the effect of adding a surfactant may be lost. When the content exceeds 3.0% by mass, the permeability to the recording medium becomes higher than necessary, and the image A decrease in density or breakthrough may occur.

-Other ingredients-
The other components are not particularly limited and may be appropriately selected as necessary. For example, pH adjusters, antiseptic / antifungal agents, rust preventives, antioxidants, ultraviolet absorbers, oxygen absorbers, And light stabilizers.

  The pH adjusting agent is not particularly limited as long as it can adjust the pH without adversely affecting the ink to be prepared, and any substance can be used according to the purpose. Examples of the pH adjuster include amines such as diethanolamine and triethanolamine, hydroxides of alkali metal elements such as lithium hydroxide, sodium hydroxide and potassium hydroxide; ammonium hydroxide and quaternary ammonium hydroxide. Quaternary phosphonium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate, potassium carbonate, and the like.

  The antiseptic / antifungal agent can suppress the growth of bacteria in the ink, and can improve the storage stability and the image quality stability. Examples of the antiseptic / antifungal agent include benzotriazole, sodium dehydroacetate, sodium sorbate, isothiazoline compounds, sodium benzoate, sodium pentachlorophenol, and the like.

  The rust preventive agent can form a film on a metal surface in contact with the liquid, such as a recording head, and prevent corrosion. Examples of the rust inhibitor include acidic sulfite, sodium thiosulfate, ammonium thiodiglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, and dicyclohexylammonium nitrite.

The antioxidant can prevent corrosion by eliminating radical species that cause corrosion. Examples of the antioxidant include phenol antioxidants (including hindered phenol antioxidants), amine antioxidants, sulfur antioxidants, phosphorus antioxidants, and the like.
Examples of the phenolic antioxidants (including hindered phenolic antioxidants) include butylated hydroxyanisole, 2,6-di-tert-butyl-4-ethylphenol, stearyl-β- (3,5 -Di-tert-butyl-4-hydroxyphenyl) propionate, 2,2'-methylenebis (4-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-tert-butylphenol), 4,4′-Butylidenebis (3-methyl-6-tert-butylphenol), 3,9-bis [1,1-dimethyl-2- [β- (3-tert-butyl-4-hydroxy-5-methylphenyl) ) Propionyloxy] ethyl] 2,4,8,10-tetrixaspiro [5,5] undecane, 1,1,3-tris (2-methyl-4- Hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tetrakis [methylene-3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate] methane, and the like.
Examples of the amine-based antioxidant include phenyl-β-naphthylamine, α-naphthylamine, N, N′-di-sec-butyl-p-phenylenediamine, phenothiazine, N, N′-diphenyl-p-phenylenediamine. 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butylphenol, 2,4-dimethyl-6-tert-butyl-phenol, butylhydroxyanisole, 2,2′-methylenebis ( 4-methyl-6-tert-butylphenol), 4,4′-butylidenebis (3-methyl-6-tert-butylphenol), 4,4′-thiobis (3-methyl-6-tert-butylphenol), tetrakis [methylene -3 (3,5-di-tert-butyl-4-dihydroxyphenyl) propionate] methane, 1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, and the like.
Examples of the sulfur-based antioxidant include dilauryl 3,3′-thiodipropionate, distearyl thiodipropionate, lauryl stearyl thiodipropionate, dimyristyl 3,3′-thiodipropionate, distearyl β. , β′-thiodipropionate, 2-mercaptobenzimidazole, dilauryl sulfide and the like.
Examples of the phosphorus antioxidant include triphenyl phosphite, octadecyl phosphite, triisodecyl phosphite, trilauryl trithiophosphite, trinonylphenyl phosphite, and the like.

Examples of the ultraviolet absorber include benzophenone ultraviolet absorbers, benzotriazole ultraviolet absorbers, salicylate ultraviolet absorbers, cyanoacrylate ultraviolet absorbers, and nickel complex salt ultraviolet absorbers.
Examples of the benzophenone-based ultraviolet absorber include 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone, 2,4-dihydroxybenzophenone, and 2-hydroxy-4-methoxybenzophenone. 2,2 ′, 4,4′-tetrahydroxybenzophenone, and the like.
Examples of the benzotriazole ultraviolet absorber include 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-4′-octoxyphenyl) benzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole, and the like.
Examples of the salicylate-based ultraviolet absorber include phenyl salicylate, p-tert-butylphenyl salicylate, p-octylphenyl salicylate, and the like.
Examples of the cyanoacrylate ultraviolet absorber include ethyl-2-cyano-3,3′-diphenyl acrylate, methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate, and butyl-2- And cyano-3-methyl-3- (p-methoxyphenyl) acrylate.
Examples of the nickel complex ultraviolet absorber include nickel bis (octylphenyl) sulfide, 2,2′-thiobis (4-tert-octylferrate) -n-butylamine nickel (II), 2,2′-thiobis. (4-tert-octyl ferrate) -2-ethylhexylamine nickel (II), 2,2′-thiobis (4-tert-octyl ferrate) triethanolamine nickel (II), and the like.

  In the ink of the ink media set of the present invention, at least a colorant, a water-soluble organic solvent, a wetting agent, and other components as necessary are dispersed or dissolved in an aqueous medium, and further stirred and mixed as necessary. Manufactured. The dispersion can be performed by, for example, a sand mill, a homogenizer, a ball mill, a paint shaker, an ultrasonic disperser, etc., and stirring and mixing are performed by a stirrer using a normal stirring blade, a magnetic stirrer, a high-speed disperser, or the like. be able to.

As physical properties of the ink, for example, the viscosity, surface tension, pH, and the like are preferably in the following ranges.
The viscosity is preferably 1.0 to 20 mPa · s at 25 ° C., and more preferably 3.0 to 10.0 mPa · s from the viewpoint of ejection stability.
As said surface tension, 40 mN / m or less is preferable at 25 degreeC, and 17-40 mN / m is more preferable. When the surface tension is 40 mN / m or less, quick fixing can be performed on almost all recording media.
As said pH, 3-11 are preferable, for example, and 6-10 are more preferable from a viewpoint of the corrosion prevention of the metal member which touches.

  There is no restriction | limiting in particular as coloring of the said ink, According to the objective, it can select suitably, Yellow, magenta, cyan, black etc. are mentioned. When recording is performed using an ink set in which two or more of these colorings are used in combination, a multicolor image can be formed. When recording is performed using an ink set in which all colors are combined, a full color image is formed. be able to.

  The ink in the ink media set of the present invention is an ink jet head that uses a piezoelectric element as pressure generating means for pressurizing ink in the ink flow path, and deforms the diaphragm that forms the wall surface of the ink flow path. A so-called piezo-type device that discharges ink droplets by changing the product (see Japanese Patent Laid-Open No. 2-51734), or a so-called thermal device that generates bubbles by heating ink in an ink flow path using a heating resistor. Type (see Japanese Patent Application Laid-Open No. 61-59911), the diaphragm and the electrode forming the wall surface of the ink flow path are arranged opposite to each other, and the diaphragm is deformed by the electrostatic force generated between the diaphragm and the electrode Thus, any ink jet such as an electrostatic type that discharges ink droplets by changing the volume of the ink flow path (see JP-A-6-71882) can be used. It can be satisfactorily used in the printer for mounting a head.

<Recording media>
The recording medium includes a support and a coating layer on at least one surface of the support, and further includes other layers as necessary.

In the recording medium, the transfer amount of pure water to the recording medium at a contact time of 100 ms measured with a dynamic scanning absorption meter is ² to 35 ml / m ² , and preferably ² to 10 ml / m ^2. .
If the transfer amount of pure water at the contact time of 100 ms is too small, beading may occur easily. If it is too large, the ink dot diameter after recording may be too small than the desired diameter.
Transfer amount to the recording medium of pure water at the contacting time 400ms measured by a dynamic scanning absorptometer is ^{3~40ml / m 2, 3~10ml / m} 2 is preferred.
If the amount of pure water transferred at the contact time of 400 ms is too small, the drying property is insufficient, and thus spur marks may be easily generated. If too much, the gloss of the image area after drying becomes low. May be easier.

  Here, the dynamic scanning absorptiometer (DSA, Papa-Pagi Technical Journal, Vol. 48, May 1994, pp. 88-92, Kuju Shigenori) absorbs liquid in a very short time. It is a device that can measure accurately. The dynamic scanning absorption meter reads the liquid absorption speed directly from the movement of the meniscus in the capillary, makes the sample a disk, and then scans the liquid absorption head in a spiral shape, and the scanning speed according to a preset pattern. Is automatically changed by a method in which the number of necessary points is measured with one sample. A liquid supply head for a paper sample is connected to a capillary via a Teflon (registered trademark) tube, and the position of the meniscus in the capillary is automatically read by an optical sensor. Specifically, the transfer amount of pure water was measured using a dynamic scanning absorption meter (K350 series D type, manufactured by Kyowa Seiko Co., Ltd.). The transfer amount at the contact time of 100 ms and the contact time of 400 ms can be obtained by interpolation from the measured value of the transfer amount at the contact time adjacent to each contact time.

The critical surface tension (γc) based on JIS K6768 on the recording surface of the recording medium is preferably 25 to 40 mN / m. When the critical surface tension (γc) is less than 25 mN / m, wetting with respect to the ink is poor and beading is likely to occur, and when it exceeds 40 mN / m, the dot shape of the ink becomes a perfect circle. It can be difficult to keep close.
Here, the critical surface tension (γc) is determined according to JIS-K6768, 1999 “Plastic-Film and Sheet-Wetting Tension Test Methods” with various surface tensions (for example, ethylene glycol monoethyl ether and formamide). 4 microliters (μl) of liquid droplets on the media printing surface, and then the contact angle measurement device (Data Physics Co., Ltd.) that captures the contact angle of each droplet when moving for 0.5 seconds. It can be determined by making a Zisman Plot from the contact angle.

-Support-
The support is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include paper based on wood fibers, and sheet-like materials such as non-woven fabrics mainly composed of wood fibers and synthetic fibers. .

  There is no restriction | limiting in particular as said paper, According to the objective, it can select suitably according to the objective, For example, wood pulp, waste paper pulp, etc. are used. Examples of the wood pulp include hardwood bleached kraft pulp (LBKP), softwood bleached kraft pulp (NBKP), NBSP, LBSP, GP, and TMP.

  As the raw material of the used paper pulp, the white paper, ruled white, cream white, card, special white, medium white, imitation, fair white, Kent, white, as shown in the used paper standard quality standard table of the used paper recycling promotion center Art, special upper limit, another upper limit, newspaper, magazine, etc. are mentioned. Specifically, printer paper such as non-coating computer paper, thermal paper, and pressure-sensitive paper as information-related paper; OA waste paper such as PPC paper; coating of art paper, coated paper, finely coated paper, matte paper, etc. Paper: High quality paper, color quality, notebook, notepaper, wrapping paper, fancy paper, medium quality paper, newsprint, reprint paper, super paper, imitation paper, pure white roll paper, uncoated paper such as milk carton, etc. Examples of used paper and paperboard include chemical pulp paper and high-yield pulp-containing paper. These may be used individually by 1 type and may use 2 or more types together.

The waste paper pulp is generally produced from a combination of the following four steps.
(1) For disaggregation, waste paper is treated with mechanical force and chemicals with a pulper to loosen it into a fibrous form, and the printing ink is peeled off from the fiber.
(2) Dust removal is to remove foreign matter (plastic etc.) and dust contained in waste paper with a screen, cleaner or the like.
(3) In the deinking, the printing ink peeled off from the fiber using a surfactant is removed from the system by a flotation method or a cleaning method.
(4) Bleaching increases the whiteness of the fiber using an oxidizing action or a reducing action.
When mixing the used paper pulp, the mixing ratio of the used paper pulp in the total pulp is preferably 40% or less from the viewpoint of curling after recording.

  As the internal filler used for the support, for example, a conventionally known pigment is used as a white pigment. Examples of the white pigment include light calcium carbonate, heavy calcium carbonate, kaolin, clay, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, White inorganic pigments such as calcium silicate, magnesium silicate, synthetic silica, aluminum hydroxide, alumina, lithopone, zeolite, magnesium carbonate, magnesium hydroxide; styrene plastic pigment, acrylic plastic pigment, polyethylene, microcapsule, urea resin And organic pigments such as melamine resin. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the internally added sizing agent used for making the support include neutral rosin sizing agents used for neutral papermaking, alkenyl succinic anhydride (ASA), alkyl ketene dimer (AKD), and petroleum resins. System sizing agents and the like. Among these, a neutral rosin sizing agent or alkenyl succinic anhydride is particularly preferable. The alkyl ketene dimer may be added in a small amount because of its high size effect, but the friction coefficient on the surface of the recording paper (media) is low and slippery, which is not preferable from the viewpoint of transportability during ink jet recording. There is.

-Coating layer-
The coating layer contains a pigment and a binder (binder), and further contains a surfactant and other components as necessary.

As the pigment, an inorganic pigment or a combination of an inorganic pigment and an organic pigment can be used.
Examples of the inorganic pigment include kaolin, talc, heavy calcium carbonate, light calcium carbonate, calcium sulfite, amorphous silica, titanium white, magnesium carbonate, titanium dioxide, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, Examples thereof include zinc hydroxide and chlorite. Among these, kaolin is particularly preferable because it has excellent glossiness and can be made close to a paper for offset printing.
The kaolin includes delaminated kaolin, calcined kaolin, engineered kaolin by surface modification, etc. In consideration of gloss expression, the particle size distribution with a particle size of 2 μm or less is 80% by mass or more. It is preferable that the kaolin which has occupies 50 mass% or more of the whole kaolin.
The amount of kaolin added is preferably 50 parts by mass or more with respect to 100 parts by mass of the binder. When the addition amount is less than 50 parts by mass, a sufficient effect on glossiness may not be obtained. The upper limit of the addition amount is not particularly limited, but is preferably 90 parts by mass or less from the viewpoint of coating suitability in consideration of the fluidity of kaolin, particularly thickening under high shear force.

Examples of the organic pigment include water-soluble dispersions such as styrene-acrylic copolymer particles, styrene-butadiene copolymer particles, polystyrene particles, and polyethylene particles. Two or more of these organic pigments may be mixed.
The amount of the organic pigment added is preferably 2 to 20 parts by mass with respect to 100 parts by mass of the total pigment in the coating layer. Since the organic pigment is excellent in gloss expression and its specific gravity is smaller than that of the inorganic pigment, it is possible to obtain a coating layer that is bulky, high gloss, and has good surface coverage. If the addition amount is less than 2 parts by mass, the above effect is not obtained. If the addition amount exceeds 20 parts by mass, the fluidity of the coating liquid deteriorates, leading to a decrease in coating operability, and economical from the viewpoint of cost. Not right.
The organic pigment includes a solid type, a hollow type, a donut type, and the like in terms of its form, but the average particle diameter is 0.2 in view of the balance of gloss development, surface covering property, and fluidity of the coating liquid. A hollow mold having a porosity of 40% or more is more preferable.

As the binder, an aqueous resin is preferably used.
As the aqueous resin, at least one of a water-soluble resin and a water-dispersible resin is preferably used. There is no restriction | limiting in particular as said water-soluble resin, According to the objective, it can select suitably, For example, modified products of polyvinyl alcohol, such as polyvinyl alcohol, anion modified polyvinyl alcohol, cation modified polyvinyl alcohol, acetal modified polyvinyl alcohol; Polyurethane; polyvinylpyrrolidone and polyvinylpyrrolidone and vinyl acetate copolymer, vinylpyrrolidone and dimethylaminoethyl / methacrylic acid copolymer, quaternized vinylpyrrolidone / dimethylaminoethyl / methacrylic acid copolymer, vinylpyrrolidone and Modified products of polyvinylpyrrolidone such as a copolymer of methacrylamidopropyl trimethylammonium chloride; Cellulo such as carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose Modified products of cellulose such as cationized hydroxyethyl cellulose; Synthetic resins such as polyester, polyacrylic acid (ester), melamine resin, or modified products thereof, polyester and polyurethane copolymer; poly (meth) acrylic acid, Examples include poly (meth) acrylamide, oxidized starch, phosphate esterified starch, self-modified starch, cationized starch, or various modified starches, polyethylene oxide, sodium polyacrylate, and sodium alginate. These may be used individually by 1 type and may use 2 or more types together.
Among these, polyvinyl alcohol, cation-modified polyvinyl alcohol, acetal-modified polyvinyl alcohol, polyester, polyurethane, a copolymer of polyester and polyurethane, and the like are particularly preferable from the viewpoint of ink absorbability.

The water-dispersible resin is not particularly limited and may be appropriately selected depending on the intended purpose. For example, polyvinyl acetate, ethylene-vinyl acetate copolymer, polystyrene, styrene- (meth) acrylate ester copolymer Polymer, (meth) acrylic acid ester polymer, vinyl acetate- (meth) acrylic acid (ester) copolymer, styrene-butadiene copolymer, ethylene-propylene copolymer, polyvinyl ether, silicone-acrylic copolymer Coalescence, etc. Further, it may contain a crosslinking agent such as methylolated melamine, methylolated urea, methylolated hydroxypropylene urea, or isocyanate, or may be a copolymer containing units such as N-methylolacrylamide and having a self-crosslinking property. A plurality of these water-based resins can be used simultaneously.
The amount of the aqueous resin added is preferably 2 to 100 parts by mass, and more preferably 3 to 50 parts by mass with respect to 100 parts by mass of the pigment. The amount of the aqueous resin added is determined so that the liquid absorption characteristics of the recording medium fall within a desired range.

  When a water-dispersible colorant is used as the colorant, the cationic organic compound is not necessarily added, but is not particularly limited and can be appropriately selected and used depending on the purpose. For example, a primary to tertiary amine, quaternary ammonium salt monomer or oligomer that reacts with a sulfonic acid group, a carboxyl group, an amino group, or the like in a direct dye or acidic dye in water-soluble ink to form an insoluble salt. A polymer etc. are mentioned, Among these, an oligomer or a polymer is preferable.

Examples of the cationic organic compound include dimethylamine / epichlorohydrin polycondensate, dimethylamine / ammonia / epichlorohydrin condensate, poly (trimethylaminoethyl methacrylate / methyl sulfate), diallylamine hydrochloride / acrylamide copolymer, (Diallylamine hydrochloride / sulfur dioxide), polyallylamine hydrochloride, poly (allylamine hydrochloride / diallylamine hydrochloride), acrylamide / diallylamine copolymer, polyvinylamine copolymer, dicyandiamide, dicyandiamide / ammonium chloride / urea / formaldehyde condensate , Polyalkylene polyamine dicyandiamide ammonium salt condensate, dimethyl diallyl ammonium chloride, polydiallyl methylamine hydrochloride, poly (diallyl dimethyl ester) Ruammonium chloride), poly (diallyldimethylammonium chloride / sulfur dioxide), poly (diallyldimethylammonium chloride / diallylamine hydrochloride derivative), acrylamide / diallyldimethylammonium chloride copolymer, acrylate / acrylamide / diallylamine hydrochloride copolymer Products, ethyleneimine derivatives such as polyethyleneimine and acrylicamine polymer, and polyethyleneimine alkylene oxide modified products. These may be used individually by 1 type and may use 2 or more types together.
Among these, low molecular weight cationic organic compounds such as dimethylamine / epichlorohydrin polycondensate and polyallylamine hydrochloride and other relatively high molecular weight cationic organic compounds such as poly (diallyldimethylammonium chloride) It is preferable to use in combination. The combined use improves the image density and further reduces feathering compared to the single use.

The cation equivalent of the cationic organic compound by colloid titration method (using polyvinyl potassium sulfate and toluidine blue) is preferably 3 to 8 meq / g. If the cation equivalent is within this range, good results can be obtained within the dry adhesion range.
Here, in the measurement of the cation equivalent by the colloid titration method, the cationic organic compound is diluted with distilled water so as to have a solid content of 0.1% by mass, and pH adjustment is not performed.

The dry adhesion amount of the cationic organic compound is preferably 0.3 to 2.0 g / m ² . When the dry adhesion amount of the cationic organic compound is lower than 0.3 g / m ² , sufficient image density improvement and feathering reduction effects may not be obtained.

  There is no restriction | limiting in particular as said surfactant, Although it can select suitably according to the objective, Any of an anionic active agent, a cationic active agent, an amphoteric active agent, and a nonionic active agent can be used. Of these, nonionic active agents are particularly preferred. By adding the surfactant, the water resistance of the image is improved, the image density is increased, and bleeding is improved.

Examples of the nonionic activator include higher alcohol ethylene oxide adduct, alkylphenol ethylene oxide adduct, fatty acid ethylene oxide adduct, polyhydric alcohol fatty acid ester ethylene oxide adduct, higher aliphatic amine ethylene oxide adduct, fatty acid amide. Ethylene oxide adduct, fat ethylene oxide adduct, polypropylene glycol ethylene oxide adduct, fatty acid ester of glycerol, fatty acid ester of pentaerythritol, fatty acid ester of sorbitol and sorbitan, fatty acid ester of sucrose, alkyl ether of polyhydric alcohol, Examples include fatty acid amides of alkanolamines. These may be used individually by 1 type and may use 2 or more types together.
The polyhydric alcohol is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include glycerol, trimethylolpropane, pentaerythritol, sorbitol, and sucrose. As the ethylene oxide adduct, a product obtained by substituting a part of ethylene oxide with an alkylene oxide such as propylene oxide or butylene oxide is also effective as long as water solubility can be maintained. The substitution rate is preferably 50% or less. 4-15 are preferable and, as for HLB (hydrophilic / lipophilic ratio) of the said nonionic activator, 7-13 are more preferable.

  The addition amount of the surfactant is preferably 0 to 10 parts by mass, and more preferably 0.1 to 1.0 part by mass with respect to 100 parts by mass of the cationic organic compound.

  Other components can be added to the coating layer as needed, as long as the object and effect of the present invention are not impaired. Examples of the other components include additives such as alumina powder, pH adjuster, preservative, and antioxidant.

There is no restriction | limiting in particular as a formation method of the said coating layer, According to the objective, it can select suitably, It can carry out by the method of impregnating or apply | coating a coating layer liquid on the said support body. The impregnation or coating method of the coating layer liquid is not particularly limited and may be appropriately selected depending on the intended purpose. For example, conventional size press, gate roll size press, film transfer size press, blade coater, rod coater It is possible to coat with various coating machines such as air knife coater and curtain coater, but from the viewpoint of cost, conventional size press, gate roll size press, film transfer size press etc. installed in paper machine It may be impregnated or deposited and finished on-machine.
There is no restriction | limiting in particular in the adhesion amount of the said coating layer liquid, According to the objective, it can select suitably, 0.5-20 g / m < ² > is preferable at solid content, and 1-15 g / m < ² > is more preferable. .
After the impregnation or application, drying may be performed as necessary. In this case, the drying temperature is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably about 100 to 250 ° C. .

The recording medium may further include a back layer on the back surface of the support, another layer between the support and the coating layer, or another layer between the support and the back layer, and a protective layer on the coating layer. Can also be provided. Each of these layers may be a single layer or a plurality of layers.
The recording medium is not particularly limited and may be appropriately selected according to the purpose. For example, in addition to the inkjet recording medium, commercially available coated paper for offset printing, coated paper for gravure printing, and the like may be used. .

<Pretreatment liquid>
The pretreatment liquid is applied to the recording surface of the recording medium at the time of ink jet recording, and contains 10 to 80% by mass of an ink fixing assistant that reduces at least one of the dispersibility and solubility of the ink, and The viscosity at 25 ° C. is 100 to 10,000 mPa · s.

  Conventionally, a colorless or light-colored pretreatment liquid containing an ink fixing aid that reduces at least one of ink dispersibility and solubility is applied by spraying to a recording medium by an ink jet method or applied with a roller. After that, a method of forming an image by an ink jet recording method has been known. However, in the conventional method, a pretreatment liquid having a low viscosity of less than 10 mPa · s has been used. This is because it is difficult to eject a liquid having a viscosity higher than that with a normal on-demand ink jet head. Also, in the case of applying with a roller, conventionally, it has not been considered to use an ink fixing aid that reduces at least one of the dispersibility and solubility of the ink at a high concentration and a high viscosity. Accordingly, even when the pretreatment liquid for the recording medium is applied with a roller, a relatively large amount of the pretreatment liquid has to be adhered to the recording medium in order to obtain the effect of improving the image quality. The method of applying the pretreatment liquid has no merit compared to the method of applying the pretreatment liquid only to the image portion by the ink jet method.

In the present invention, the pretreatment liquid contains an ink fixing aid that reduces at least one of the dispersibility and solubility of the ink at a high concentration of 10 to 80% by mass, and the viscosity of the pretreatment liquid is 10 to 10%. By setting the viscosity to 1,000 mPa · s, even in a state where the amount of the pretreatment liquid applied to the recording medium was extremely small, a good image without bleeding, feathering, and back-through was obtained. Therefore, even if the pretreatment liquid has a small adhesion amount of 0.5 to 10 g / m ² , a good image can be obtained.

The content of the ink fixing aid that lowers at least one of the dispersibility and solubility of the ink in the pretreatment liquid is 10 to 80% by mass. When the content is less than 10% by mass, the pretreatment liquid needs to have an adhesion amount of about 10 to 30 g / m ² in order to improve the image, and the conventional pretreatment liquid has a moisture content in the liquid. Due to the high content, there is a problem that cockling occurs in the recording medium provided. Even when a large amount of the pretreatment liquid was applied in this way, the effect of improving feathering was not sufficient due to color boundary blurring. On the other hand, when the content of the ink fixing aid exceeds 80% by mass, the liquid component in the liquid evaporates or precipitates in the liquid easily due to the influence of heat history such as cooling of the liquid. It becomes difficult to maintain reliability when applying. Further, when the content exceeds 80% by mass, it is difficult to uniformly apply the liquid to the recording medium. The optimal content of the ink fixing aid in the pretreatment liquid varies depending on factors such as the compound used, the ink formulation, and the amount of ink printed per unit area, but is preferably in the range of 20 to 60% by mass. It is.

  The viscosity of the pretreatment liquid is 100 to 10,000 mPa · s (25 ° C., rotor No. 4, rotation speed 30 rpm) with a B-type viscometer, preferably in the range of 100 to 3,000 mPa · s, and 300 to 2 The range of 1,000 mPa · s is more preferable. In this range, the effect of improving the image quality and the dryness of the pretreatment liquid are well balanced.

  With conventional low-viscosity pretreatment liquids, if the pretreatment liquid is a permeable liquid, it will penetrate deep into the recording medium, particularly plain paper, and the reaction with the ink will not occur on the surface of the recording medium. The effect of preventing omission, prevention of feathering, and blurring of color boundaries is reduced. Conversely, in a low-viscosity pretreatment liquid, if the liquid is formulated to have reduced permeability to the recording medium, the reaction with the ink occurs on the surface of the recording medium, but the ink remains on the surface of the recording medium for a long time. For this reason, when the effect of preventing the blurring of the color boundary is weakened or when high-speed printing is performed, there is a problem that the permeability is poor, that is, the drying property of the image is deteriorated. In this case, in order to obtain a sufficient image quality improvement effect, if a large amount of pretreatment liquid is applied, the pretreatment liquid penetrates into the recording medium, and the colorant also penetrates into the recording medium. This leads to a decrease in concentration. Further, the solvent component contained in the pretreatment liquid tends to cause curling and cockling of the recording medium. When the viscosity of the pretreatment liquid exceeds 10,000 mPa · s, not only is it difficult to uniformly apply the liquid to the recording medium, but the pretreatment liquid does not penetrate the recording medium at all. This is not preferable because a sticky feeling remains on the recording medium.

In the present invention, an image is formed with ink after the pretreatment liquid is applied to the recording medium and before the pretreatment liquid is dried. If the pretreatment liquid is dried by heating the recording medium or leaving it at room temperature for a long time, bleeding or feathering occurs in the color boundary. In order to improve the image quality by printing an image after making it dry, an applied amount exceeding 30 g / m ² is required, which is economically undesirable.

Next, the composition of the pretreatment liquid used for the ink media set of the present invention will be described.
Currently, water-based inks that are generally used contain an anionic compound or negatively charged particles in most cases. Therefore, it reacts with an anionic compound contained in the ink, an anionic pigment, an anionic polymer compound, an anionic emulsion, or negatively charged particles, or at least the dispersibility and solubility of the ink. As an ink fixing aid for reducing any of them, the pretreatment liquid preferably contains a cationic compound. Among the cationic compounds, the cationic polymer is particularly preferable because it has a high ability to react with an anionic compound or negatively charged particles in the ink.

  When the pretreatment liquid is cationic, it is on the surface of the recording medium, and the ionic interaction with the anionic component in the ink improves the image quality, such as reproducibility of fine lines, improved water resistance, and prevention of bleeding. Is obtained. As described above, a high-viscosity pretreatment liquid that cannot be used in the pretreatment method in which droplets are ejected by the ink jet method can be used. The pretreatment liquid can contain a cationic polymer at a high concentration. By depositing with a thin layer at a high concentration, the amount of deposition can be reduced and the cationic polymer stays in the vicinity of the surface, so that the image quality is remarkably improved and curling, cockling, etc. of the recording medium can be suppressed.

In the present invention, since the viscosity of the pretreatment liquid is high, the range of material selection is remarkably wide as compared with the conventional pretreatment liquid. In order to maintain a low viscosity, the material used for the conventional pretreatment liquid, for example, in the case of a polymer, has a significant restriction on the degree of polymerization, molecular weight, two-dimensional, and three-dimensional structure.
In the pretreatment liquid, as the ink fixing aid for reducing the solubility or dispersibility of the ink, the cationic polymer is at least one selected from polymers represented by the following structural formulas (1) to (20) It is preferable that
However, in said structural formula (1), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. R represents an alkylene group having 1 to 3 carbon atoms. n represents the number of polymerizations.
However, in said structural formula (2), n represents the number of polymerization.
However, in the structural formula (3), X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. R ₁ represents either a hydrogen atom or CH ₃ . R ₂ , R ₃ , and R ₄ may be the same as or different from each other, and represent either a hydrogen atom or an alkyl group. n represents the number of polymerizations.
However, in said structural formula (4), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (5), n represents the natural number of 5-30.
However, in said structural formula (6), n represents the number of polymerization.
However, in the structural formula (7), X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (8), n represents the number of polymerization.
However, the structural formula (9), Z and Y each represent -OCOCH ₃ or -OH. R ₅ represents an alkylene group having 1 to 4 carbon atoms. n, l, and m each represent the number of polymerizations.
However, in the structural formula (10), R ₆ represents an alkyl group. X ⁻ represents an anion selected from a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in the structural formula (11), R ⁷ and R ⁸ may be the same as or different from each other, and represent either a hydrogen atom or an alkyl group. X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (12), X < ^- > represents the anion in any one of a halogen ion, nitrate ion, nitrite ion, and acetate ion. n represents the number of polymerizations.
However, in said structural formula (13), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (14), j and k represent a natural number of 2-6, respectively. n represents the number of polymerizations.
However, in the structural formula (15), X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (16), X < ^- > represents the anion in any one of a halogen ion, nitrate ion, nitrite ion, and acetate ion. Q represents a copolymerizable monomer component. n and m each represent the number of polymerizations.
However, in said structural formula (17), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (18), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in the structural formulas (19) and (20), D ¹ represents a substituent represented by any of the following structural formulas (21) and (22). D ² is independent of D ¹ and represents any one of a hydrogen atom, the following structural formula (21), and the following structural formula (22). n represents a natural number, and m represents an integer of 0 or more.
However, in the structural formula (21) and the structural formula (22), R ₉ and R ₁₀ may be the same as or different from each other, and are either a hydrogen atom, an alkyl group, or an aryl group. Represents. R ₁₁ and R ₁₂ may be the same as or different from each other, and each represents a hydrogen atom, an alkali metal, or a substituent represented by the following structural formula (23).
However, in the structural formula (23), R _{13 to} R ₁₆ may be the same as or different from each other, and are any of a hydrogen atom, an alkyl group, an aryl group, a hydroxyalkyl group, and a benzyl group. Represents

  The cationic polymer containing the structural formulas (19) and (20) as structural units preferably has a mass average molecular weight of 1,000 to 100,000, more preferably 2,000 to 50,000, and 2,000 to 30,000. Further preferred. If the mass average molecular weight is greater than 100,000, it is difficult to dissolve in a solvent, so that the pretreatment liquid becomes non-uniform, and uneven image quality is likely to occur. If it is less than 1,000, bleeding is prevented and water resistance is increased. The improvement effect may be reduced.

Further, in order to obtain high reactivity with the anionic component, the cationic degree at pH 4 of the cationic resin is preferably 3 meq / g or more, and more preferably 3.5 meq / g or more.
Here, the said cation degree is calculated | required by the colloid titration using a polyvinyl potassium sulfate reagent. Specifically, it can be determined by the following procedure. First, 90 ml of deionized water is taken into a conical beaker, 10 ml of a 500 ppm aqueous solution of a sample (converted to a dry product) is added to adjust the pH to 4.0 with an aqueous hydrochloric acid solution, and the mixture is stirred for about 1 minute. Next, add 2-3 drops of toluidine blue indicator and titrate with N / 400 potassium potassium sulfate reagent (N / 400 PVSK). The titration rate is 2 ml / min, and the end point is the time when the sample water changes from blue to magenta and is held for 10 seconds or more. Cation degree (meq / g) = (N / 400 PVSK titration) × (N / 400 PVSK titer) / 2.
The higher the cation degree, the stronger the cationicity, and the more efficiently the anionic component in the ink can be reacted. Therefore, the necessary amount of pretreatment liquid can be reduced, and the curling and cockling of the recording medium does not occur. In addition, a high-quality image can be obtained. The cationic polymer may be used alone or in combination of two or more.

  In order to improve the image quality by reacting with an anionic compound such as a dye or pigment dispersant in the ink, it is particularly preferable to use a cationic polymer as described above. However, it is also effective to add a monomer compound that reacts with the anionic compound represented by the following structural formula to reduce solubility and dispersibility to the pretreatment liquid, and in particular, it is cationic by using it together with a cationic polymer. This is preferable in that the reaction between the polymer and the anionic compound in the ink is promoted.

In the structural formula, X ⁻ represents an anion selected from halogen ion, nitrate ion, nitrite ion, and acetate ion. R _{24 to} R ₂₆ are alkyl groups having a total carbon number of 5 to 32 of R ₂₄ , R ₂₅ , and R ₂₆ .

In the cationic monomer compound, a compound in which R ₂₅ and R ₂₆ are both methyl groups and R ₂₄ has 10 to 20 carbon atoms is highly soluble and can react with an anionic compound in the ink. It is preferable because it has both the effects of reducing solubility and dispersibility. When R ₂₅ or R ₂₆ is an alkyl group having more carbon atoms than the methyl group or a compound in which R ₁ has more than 10 to 20 carbon atoms, the solubility in the pretreatment liquid is lacking and storage Problems such as precipitation occur due to environmental changes. A compound having a small number of carbons is excellent in dissolution stability, but has a small ability to reduce solubility and dispersibility by reaction with an anionic compound in the ink, and the effect of improving image quality is small.

  Specific examples of the cationic monomer compound represented by the structural formula include compounds represented by the following structural formulas C-1 to C-7. These cationic compounds can be used alone or as a mixture in the pretreatment liquid.

  As these cationic monomer compounds, those synthesized as appropriate may be used, or commercially available products may be used. Examples of the commercially available products include trade names Cation S, Cation SK, Cation M, Cation G-50 (all manufactured by Sanyo Chemical Industries, Ltd.); Cation F2-35R, Cation F2-40E, Cation M2-100, Cation S2-100 (all manufactured by Nippon Oil & Fat Co., Ltd.); Sanizar C, Sanizol B-50 (all manufactured by Kao Corporation) and the like.

  The cationic monomer compound and the cationic polymer represented by any one of the structural formulas (1) to (20) are preferably used in combination for the pretreatment liquid. This is because the cationic polymer represented by any of the structural formulas (1) to (20) has an appropriate surface activity and makes the pretreatment liquid wettable with respect to the recording medium. Presumed. When general ink is applied to high-quality paper, which is a typical recording medium, microscopically, there are places where the ink is easily wetted and where it is difficult to get wet depending on the distribution of the surface sizing agent. It is estimated that image quality degradation such as density unevenness in the solid image portion occurs. Since the pretreatment liquid is applied uniformly to a recording medium such as plain paper and then the ink is adhered to the recording medium, irregular wetting is reduced, so there is less feathering and excellent reproducibility of fine lines etc. It is possible to obtain an image with high image density without blurring and high image density.

  In addition to using the cationic polymer dissolved in water as a fixing aid in the ink, it is also effective to use a pretreatment liquid in which cationic particles are dispersed and suspended. However, in the cationic emulsion, the cation concentration in the pretreatment liquid tends to be low, and in order to sufficiently improve the image quality, a water-soluble cationic polymer, a cationic surfactant having a higher alkyl group, etc. It is preferable to use together with other cationic compounds.

  Examples of liquids in which cationic particles are dispersed and suspended include cationic resin emulsions and cationic white or light color pigment dispersions. Examples of cationic emulsions include, for example, styrene-acrylic systems such as Acryt UW319-SX, Acryt RKW-460, Acryt RKW-400SX, Acryt RKW-450SX, Acryt RKW-450 (all manufactured by Taisei Kako Co., Ltd.). The cationic emulsion is commercially available.

  By adding a cationic resin emulsion to the pretreatment liquid, a glossy image can be obtained compared to the case where a cationic polymer having water solubility is used alone, and the water resistance and friction resistance of the image are high. Can have sex. Moreover, the light resistance of an image can be enhanced by incorporating an ultraviolet absorber, an antioxidant, a quencher, or the like in the emulsion.

As another example of a liquid in which cationic particles are dispersed and suspended, a dispersion of silica having cationic properties can be exemplified. For example, silica sol which is a dispersion of spherical silica of about 0.1 μm dispersed in water is preferably used. As the cationic silica, commercially available products can be used. For example, Snowtex AK (manufactured by Nissan Chemical Industries, Ltd.), SMR8-17-109SMSG 3CS (manufactured by Grace Japan Co., Ltd.), CEP10AK97002 (manufactured by CABOT), etc. Can be mentioned.
However, even when cationic silica is used, the cationic silica alone tends to have a low cation concentration in the pretreatment liquid as in the case of the cationic resin emulsion. It is preferably used in combination with other cationic compounds such as a cationic polymer and a cationic surfactant having a higher alkyl group. By adding cationic silica to the pretreatment liquid, the sticky feeling immediately after image printing can be reduced as compared with the case where a cationic polymer having water solubility is used alone.

  In the pretreatment liquid, it is also effective to use a polyvalent metal salt as an ink fixing aid for reducing at least one of the dispersibility and solubility of the ink. However, the polyvalent metal salt generally has a slightly weaker ability to lower the solubility and dispersibility of the ink as compared with the cationic polymer. It is important to use an anionic compound. When a polyvalent metal salt is used, it is preferable to use a dye having two or more, preferably three carboxyl groups or sulfonic acid groups in one molecule. In addition, in the case of an ink using a pigment, it is preferable to use a polymer compound having a carboxyl group as a dispersant or a pigment having a carboxyl group introduced by a covalent bond. When a polyvalent metal salt is used for the pretreatment liquid, when a dye is used for the ink, a complex is formed between the dye and the metal, and the light resistance of the recorded image is improved.

  Examples of the polyvalent metal salt include aluminum chloride, calcium chloride, aluminum nitrate, magnesium nitrate, magnesium chloride, calcium nitrate, magnesium hydroxide, aluminum sulfate, and ammonium alum. Specifically, magnesium nitrate hexahydrate, magnesium acetate tetrahydrate, calcium nitrate tetrahydrate, calcium acetate monohydrate, calcium chloride anhydride, calcium lactate pentahydrate , Calcium formate, anhydrous, magnesium benzoate, trihydrate, magnesium sulfate, heptahydrate, and the like.

In addition to the cationic polymer represented by any of the structural formulas (1) to (20), for example, a dicyandiamide / formalin heavy condensed product, a dicyandiamide / diethylenetriamine heavy condensed product, and epichlorohydrin as a cationic compound that insolubilizes the colorant. dimethylamine addition polymer, dimethyl diallyl ammonium chlorides, SO ₂ copolymer, dimethyl diallyl ammonium chlorides polymers, polymer of diallylamine salt-SO ₂ copolymer allylamine salt, dialkylaminoethyl (meth) Akurureto quaternary Can contain salt polymer, polyallylamine, cationic epoxy resin, polyethyleneimine, polyacrylamide, poly (meth) acrylic ester, polyvinylformamide, cationic emulsion, polyvalent metal salt, etc. A.

  As these cationic polymers, commercially available products can be used. Specifically, Sunstat E-818, Sunfix 70, Sunfix 555C, Sunfix LC-55, SunFux PAC-700 Conch, Sanyo Elion A-3, Sunfix 414, Sunfix 555, Sunfix PRO-100, Sunfix 555US, Cellopor YM-500 (all manufactured by Sanyo Chemical Industries, Ltd.); # 675, # FR-2P, # 1001 (any Also available from Sumitomo Chemical Co., Ltd.); LUPASOL SC61B (manufactured by BASF). Moreover, ZP-700 (vinyl formamide type), MP-184 (polyacrylic acid ester type), MP-173H (polymethacrylic acid ester type), MP-180 (polymethacrylic acid ester type), MX-0210 (polymethacrylic acid type) Acid ester), MX-8130 (polyacrylate ester), E-395 (polyacrylate ester), E-305 (polyacrylate ester), Q-105H (dicyandiamide), Neo-600 ( Polyacrylamide type), Q-101 (polyamine type), Q-311 (polyamine type), Q-501 (polyamine type) (all manufactured by Hymo Co., Ltd.), Super Flock 2490 (Polyacrylate), Super Flock 3180, 3380, 3580, 3880, 3390, 3590, 3500 SD2081 (polyacrylamide), Acofloc C498T, C498Y (polyacrylic acid ester), Super flock 1500, 1600, Acofloc C481, C483, C485, C488, C480 (polymethacrylate), Acofloc C567, C573, C577, C581 (Polyamine system) (all manufactured by Mitsui Cytec Co., Ltd.); PAS-A-1, PAS-A-5, PAS-A-120L, PAS-A-120S, PSA-J-81, PAS-880, PAS- 92 (diallyldimethylammonium salt copolymer), PAS-H-5L, PAS-H-10L, PAS-M-1 (diallyldimethylammonium salt polymer), PAA-HCl-3L, PAA-HCl-10L (Polyallylamine hydrochloride , PAA-10C (polyallylamine) (all manufactured by Nitto Boseki Co., Ltd.), and the like.

  Other examples of cationic quaternary ammonium salts that can be used in the present invention include Ionette D46, Ionette LEC, Securyl VN, Sunstat 1200, Sunstat KT-305C, Cation G-50, Ionette RK-15 (all of which are Sanyo) Kasei Kogyo Co., Ltd.).

  Since the reactivity between the cationic polymer in the pretreatment liquid and the anionic component in the ink is the most efficient in the liquid phase, the pretreatment liquid is applied to the recording medium by an applying means that abuts, It is preferable to print with ink before the pretreatment liquid dries. If high reactivity can be secured, the amount of pretreatment liquid used can be further reduced, and the image quality can be improved without causing curling and cockling of the recording medium.

  The ink used in the ink media set of the present invention preferably contains 20 to 80% by mass of water and a water-soluble liquid compound. If it is less than 20% by mass, the dissolution stability of the cationic polymer is poor, and the pretreatment liquid is gelled or insoluble matter is generated.

  In the pretreatment liquid, it is preferable to use 20 to 80% by mass of a water-soluble solvent having a boiling point higher than that of water as a water-soluble liquid compound. Further, when the viscosity changes due to evaporation of a solvent component such as water in the pretreatment liquid, the amount applied to the recording medium also changes, and it is not possible to ensure a constant image quality. In addition to preventing drying, in order to make the pretreatment liquid of the recording medium have the desired physical properties, to improve the dissolution stability of the compound and other additives that insolubilize the colorant in the ink, and to apply the pretreatment liquid of the recording medium. The following water-soluble organic solvents can be used for the purpose of stabilizing the process characteristics. If it is less than 20% by mass, the effect of suppressing the evaporation of water from the pretreatment liquid is small, the change in the viscosity of the pretreatment liquid due to the evaporation of water becomes large, and the applied amount lacks stability. Moreover, due to water evaporation, the dissolution stability of the cationic polymer also deteriorates, and the pretreatment liquid is gelled or insoluble matter is generated.

  The water-soluble organic solvent used in the pretreatment liquid is not particularly limited and may be appropriately selected depending on the intended purpose. For example, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,5 -Polyhydric alcohols such as pentanediol, 1,6-hexanediol, glycerin, 1,2,6-hexanetriol, 1,2,4-butanetriol, 1,2,3-butanetriol, and petriol Ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene Polyhydric alcohol alkyl ethers such as recall monoethyl ether; polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether; N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, Nitrogen-containing heterocyclic compounds such as 2-pyrrolidone, 1,3-dimethylimidazolidinone and ε-caprolactam; amines such as monoethanolamine, diethanolamine and triethanolamine; sulfur-containing compounds such as sulfolane and thiodiethanol; propylene Examples include carbonate, ethylene carbonate, and γ-butyrolactone. These solvents can be used alone or in combination with water.

  The optimum type and composition ratio of the water-soluble organic solvent used in the pretreatment liquid are preferably selected according to other materials used in the pretreatment liquid. In the present invention, since an ink fixing aid such as a cationic polymer that lowers the solubility and dispersibility of the ink is used at a high concentration, it is important to ensure the solubility of the compound.

  Among these, diethylene glycol, thiodiethanol, polyethylene glycol 200 to 600, triethylene glycol, glycerin, 1,2,6-hexanetriol, 1,2,4-butanetriol, petriol, 1,5-pentanediol, N-methyl-2-pyrrolidone, N-hydroxyethylpyrrolidone, 2-pyrrolidone, and 1,3-dimethylimidazolidinone. By using these, the solubility of insolubilizing compounds such as cationic polymers can be maintained. The pretreatment liquid can be applied to the recording medium with high reliability.

  Although water can be added to the pretreatment liquid, the amount of water added is preferably smaller than that of the conventional pretreatment liquid in order to maintain the stability of application of the liquid to the recording medium. Further, the composition ratio of water is less than or close to the moisture ratio that the composition obtained by removing water from the pretreatment liquid absorbs in the equilibrium state with the atmospheric humidity in the usage environment of the recording apparatus. This not only prevents the moisture from evaporating during the application of the pretreatment liquid to the recording medium or during the leaving period of the application apparatus, but also from the application of the pretreatment liquid to the recording medium until the image is recorded. Even if the time is as long as about 5 minutes, for example, an image quality improvement effect equivalent to that obtained when image recording is performed immediately after application can be obtained. In particular, by reducing the relative moisture content below the equilibrium moisture content at 60%, even if the use environment of the pretreatment liquid application device changes, the water evaporates from the pretreatment liquid in almost all use environments. Problems such as uneven application and excessive application amount can be prevented.

  The water content is preferably 40% by mass or less, and more preferably 10 to 30% by mass. If the amount of water exceeds 40% by mass, the viscosity of the liquid increases or gelation occurs due to the evaporation of water during application of the pretreatment liquid to the recording medium or during the standing period of the applying apparatus. The problem of precipitation of insoluble matter is likely to occur. Also, during the time from application of the pretreatment liquid to image recording, moisture evaporates, the fluidity of the pretreatment liquid is lost, the reaction with the ink becomes slow, and sufficient image quality improvement effect is achieved. Is difficult to obtain. Further, when there is a time difference from application of the pretreatment liquid to image recording at the leading edge or the trailing edge of the image, a problem arises that a difference in image quality occurs. Even if the water content is less than 10% by mass, the solubility of the cationic compound tends to be insufficient, and problems of gelation and generation of insoluble matter are likely to occur.

  The pretreatment liquid preferably contains a monohydric alcohol, thereby preventing the occurrence of uneven coating due to foaming of the pretreatment liquid of the recording medium, and the pretreatment liquid of the recording medium is added to the recording medium. When the image is formed by ejecting the ink as droplets and adhering to the recording medium after the contact and application, an image having a uniform density can be obtained.

  Since the pretreatment liquid contains water and a water-soluble solvent as main solvents, it does not adversely affect the wettability and permeability between the recording medium provided with the pretreatment liquid and the ink. Therefore, good image quality can be obtained even when high-speed recording is performed. Further, the various components constituting the pretreatment liquid are stable and do not cause any change in the characteristics even after being stored for a long time.

  In the pretreatment liquid, a surfactant and / or a wetting accelerator is added, the surface tension is adjusted to 40 mN / m or less, and the wettability to the applying means used for applying the recording medium and the pretreatment liquid is improved. It is preferable to increase. By increasing the wettability, the pretreatment liquid uniformly adheres to the recording medium, so that the image quality can be improved with a small applied amount. Further, by improving the wettability to the liquid application means such as a rubber roller and a metal roller, uniform application to the recording medium is facilitated.

  Furthermore, the pretreatment liquid may contain a surfactant. Irregular wetting due to the distribution of the surface sizing agent of the recording medium is reduced when the pretreatment liquid containing the cationic resin and the surfactant is applied to the recording medium such as plain paper and then the ink is attached to the recording medium. Therefore, it is possible to obtain an image with low image feathering, excellent reproducibility of thin lines, etc., high image quality without blurring of color boundaries, and high image density. This is presumably because the ink penetrates uniformly into the recording medium and the colorant becomes insoluble and remains in the vicinity of the surface of the recording medium.

  Examples of the surfactant include anionic surfactants such as sodium dodecylbenzenesulfonate, sodium laurate, ammonium salt of polyoxyethylene alkyl ether sulfate; distearyldimethylammonium chloride, stearyldimethylbenzylammonium chloride, stearyldimethylchloride Cationic surfactants such as benzylammonium chloride, stearyltrimethylammonium chloride, cetyltrimethylammonium chloride, myristyldimethylbenzylammonium chloride, benzalkonium chloride, lanolinium ethylsulfate fatty acid aminopropylethyldimethylammonium chloride, didecyldimethylammonium chloride; imidazoline derivatives, etc. Amphoteric surfactants: polyoxyethylene alkyl ether, polyoxyethylene alkyl Nonionics such as phenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkyl amine, polyoxyethylene alkyl amide, polyoxyethylene propylene block polymer, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, ethylene oxide additive of acetylene alcohol Surfactant; Fluorosurfactant etc. are mentioned.

  As content of surfactant in the said pre-processing liquid, 0.1-50 mass% is preferable. Moreover, in order to ensure the uniformity of the pretreatment liquid, a cationic surfactant is particularly preferable among the surfactants. Thereby, the wettability between the ink and the recording medium surface is improved, and an image with high image quality and high image density and excellent water resistance can be obtained. Examples of the cationic surfactant include Ionette D46, Ionette LEC, Securyl VN, Sunstat 1200, Sunstat KT-305C, Cation G-50, and Ionette RK-15 (all manufactured by Sanyo Chemical Industries, Ltd.). It is done.

  As a result of examining the permeability of the ink into a recording medium such as plain paper, it contains a surfactant represented by the following structural formulas (i) to (Vi) and a dicyandiamide resin that insolubilizes the coloring material in the ink. By using the pretreatment liquid for the recording medium, the permeability of the ink to the recording medium is improved, the dye can be retained on the surface of the recording medium, the feathering is less, the reproducibility of fine lines is excellent, and the color boundary is not blurred. An image with high image quality and high image density and excellent water resistance can be obtained.

However, in the structural formula (i), R ₁₇ represents any of a lauryl group, a stearyl group, and a myristyl group.
In the Structural Formula _{(ii), R 18} and _{R 19} represents a branched carbon atoms and optionally three or more alkyl groups. M represents an alkali metal, ammonium, alkanolamine, quaternary ammonium or quaternary phosphonium.
In the Structural Formula _{(iii), R 20} and _{R 21} represents an alkyl group of 5-7 carbon atoms, m is an integer of 5-20.
In the Structural Formula _{(iv), R 22} represents an carbon chain optionally branched having 6 to 14 carbon atoms, n is an integer of 5-20.
However, in said structural formula (v), m and n represent the integer of 0-20, respectively.
However, in the structural formula (vi), R ₂₃ represents a carbon chain having 6 to 14 carbon atoms which may be branched. m and n represent the integer of 0-20, respectively.

  According to the present invention, the permeability of the ink to the recording medium is improved, so that the fast fixing speed of the image is increased, thereby enabling high-speed recording. This is because when a recording medium pretreatment liquid containing the specific surfactant and a dicyandiamide resin that insolubilizes the colorant in the ink is applied to a recording medium such as plain paper, the ink is attached to the recording medium. This is probably because irregular wetting due to the distribution of the surface sizing agent of the recording medium is reduced, so that the ink penetrates the recording medium uniformly and the colorant becomes insoluble and remains in the vicinity of the surface of the recording medium.

  The content of the surfactant represented by the structural formulas (i) to (vi) in the pretreatment liquid is preferably 0.1 to 50% by mass, and more preferably 0.1 to 10% by mass. Of the surfactants, a benzalkonium chloride salt of a cationic surfactant represented by the structural formula (i) is preferable. Thereby, the wettability between the ink and the surface of the recording medium can be further improved, the ink penetration speed into the recording medium can be further increased, and an image with high image quality and high image density and excellent water resistance can be obtained. Moreover, high-speed recording can be performed.

  Further, a wetting accelerator other than a surfactant can be added for the purpose of adjusting the surface tension, and the solvent other than the surfactant is not particularly limited and can be appropriately selected according to the purpose. For example, alkyl or aryl ethers of polyhydric alcohols such as diethylene glycol monophenyl ether, ethylene glycol monophenyl ether, ethylene glycol monoallyl ether, diethylene glycol monophenyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, tetraethylene glycol chlorophenyl ether; 1 , 6-hexanediol, 1,5-pentanediol, 2-ethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1, - polyhydric alcohols such as hexane diol, polyoxyethylene polyoxypropylene block copolymer, ethanol, and the like lower alcohols such as 2-propanol.

  It is preferable to add a binder resin to the pretreatment liquid in order to improve fixability. The first binder resin is not particularly limited and can be appropriately selected according to the purpose. For example, acrylic resin, vinyl acetate resin, styrene-butadiene resin, vinyl chloride resin, acrylic-styrene resin, Examples thereof include butadiene-based resins and styrene-based resins.

The pretreatment liquid preferably contains 0.1 to 5% by mass of a preservative and fungicide. Since the pretreatment liquid is applied while being in contact with the recording medium, for example, contamination-causing substances such as paper dust are likely to be mixed in, and the pretreatment liquid may be altered, resulting in a change in the amount of adhesion due to the alteration and a reduction in the image quality improvement effect itself. There is. Therefore, by adding 0.1 to 5% by mass of an antiseptic and fungicidal agent, a pretreatment that can act stably over a long period of time can be obtained. When the addition amount is less than 0.1% by mass, the antiseptic and antifungal effects may be insufficient, and when it exceeds 5% by mass, the image quality may be deteriorated.
The antiseptic / antifungal agent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include sodium benzoate, sodium pentachlorophenol, sodium 2-pyridinethiol-1-oxide, sodium sorbate, dehydro Examples thereof include sodium acetate, 1,2-dibenzisothiazolin-3-one (Abysha's Proxel CRL, Proxel BDN, Proxel GXL) and the like.

  It is preferable that the pH value of the pretreatment liquid in the first half is kept almost neutral. In the case where stainless steel or nickel is used as the liquid application member, it is preferable to keep the pH value in the range of 8 to 11 in the sense of suppressing the corrosiveness, but the solubility of the cation resin is generally in a region where the pH value is relatively low. In view of the balance between the two, a region close to neutrality is preferable. In order to adjust the pH value of the pretreatment solution to a desired value, the pretreatment solution contains amines such as diethanolamine and triethanolamine, and hydroxides of alkali metal elements such as lithium hydroxide, sodium hydroxide and potassium hydroxide. An alkali metal carbonate such as ammonium hydroxide, quaternary ammonium hydroxide, quaternary phosphonium hydroxide, lithium carbonate, sodium carbonate, potassium carbonate, or the like can be added.

  In addition, in order to improve the light resistance of the image, an ultraviolet absorber, an antioxidant or the like can be added to the pretreatment liquid. Examples of the ultraviolet ray inhibitor include various benzotriazoles, salicylic acid esters, benzophenones, cyanoacrylates, benzofuran derivatives, substituted acrylonitriles, substituted -N-phenylaminoethylene, pyrone, methylenemalonic acid esters, and cinnamon. Suitable examples include acid esters, phenyl salicylates, and hindered amines. Antioxidants include various phenolic, sulfur-based, phosphoric acid-based, naphthol-based, hindered phenols, paraphenylenediamines, hydroquinones, organic sulfur compounds, organic phosphorus compounds, hindered amines, and chroman-based antioxidants. Preferable examples include spiroindane, hydrazine and the like. These ultraviolet ray inhibitors and antioxidants may be added as emulsions in order to increase dispersibility.

(Ink cartridge and pretreatment liquid cartridge)
The ink cartridge of the present invention contains the ink in the ink media set of the present invention in a container, and further includes other members appropriately selected as necessary.
The pretreatment liquid cartridge of the present invention contains the pretreatment liquid in the ink media set of the present invention in a container, and further has other members appropriately selected as necessary.

The container is not particularly limited, and its shape, structure, size, material and the like can be appropriately selected according to the purpose. Preferred examples include those possessed.

Next, the ink cartridge and the pretreatment liquid cartridge will be described with reference to FIGS. Here, FIG. 5 is a view showing an example of the ink cartridge and the pretreatment liquid cartridge of the present invention, and FIG. 6 is a view including the case (exterior) of the ink cartridge and the pretreatment liquid cartridge of FIG.
As shown in FIG. 5, the ink cartridge and the pretreatment liquid cartridge are filled into the ink bag 241 from the ink inlet 242 and exhausted, and then the ink inlet 242 is closed by fusion. In use, the needle of the apparatus main body is pierced into the ink discharge port 243 made of a rubber member and supplied to the apparatus.
The ink bag 241 is formed of a packaging member such as a non-permeable aluminum laminate film. As shown in FIG. 6, the ink bag 241 is usually housed in a plastic cartridge case 244 and is detachably mounted on various ink jet recording apparatuses.

(Inkjet recording method and inkjet recording apparatus)
The inkjet recording method of the present invention uses the ink media set of the present invention to apply a pretreatment liquid to the recording surface of a recording medium, and to stimulate ink according to an image signal before the pretreatment liquid dries. And a step of causing the ink to fly and recording an image on a recording medium, and further including other steps appropriately selected as necessary.
The ink jet recording apparatus of the present invention uses the ink media set of the present invention, means for applying a pretreatment liquid to the recording surface of the recording medium, and stimulating the ink according to the image signal before the pretreatment liquid dries. And a means for causing the ink to fly and recording an image on a recording medium, and further having other means appropriately selected as necessary.

  The method for applying the pretreatment liquid to the recording surface of the recording medium is not particularly limited and can be appropriately selected depending on the purpose. However, the pretreatment liquid is more suitable than a non-contact means such as an ink jet method. It is preferable to apply the pretreatment liquid to the surface of the recording medium by an applying means that contacts the recording medium.

Examples of the means for applying the pretreatment liquid in contact with the recording medium include a roller coating machine, a wire bar, a coating blade, and a means for contacting a foam impregnated with the pretreatment liquid. Furthermore, the recording medium pretreatment liquid applied by the contact applying means can also contain a number of additives that could not be compounded by the above-described conventional methods. Can greatly expand the degree of freedom of formulating Among the means for applying contact, by using a roller, a high-viscosity pretreatment liquid can be uniformly applied with a simple apparatus configuration so that a sufficient image quality improvement effect can be obtained. This is preferable because the applying means can be manufactured at a low cost and in a compact manner. In this way, a high-concentration pre-treatment liquid containing a high-concentration fixing agent is applied to the recording medium in an amount much smaller than the conventional pre-treatment liquid application amount by means of contact application. Thus, it is possible to prevent the occurrence of cockling of the recording medium that has occurred in the conventional method, and to obtain an effect of improving the image quality over the conventional method.
The adhesion amount of the pretreatment liquid is preferably 0.5 to 10 g / m ² in solid content on the recording surface of the recording medium. As a result, curling of the recording medium can be suppressed more effectively. If the adhesion amount is less than 0.5 g / m ² , the effect of improving the image quality is insufficient. If the adhesion amount is more than 10 g / m ² , the recording medium causes curling or cockling, and the adhesion amount is too large. Loss density increases.

Before the pretreatment liquid dries, the step of applying a stimulus to the ink according to the image signal and flying the ink to record the image on the recording medium applies the stimulus to the ink in the ink media set of the present invention. In this step, the ink is ejected to form an image.
The ink flying means is means for forming an image by applying a stimulus to the ink in the ink media set of the present invention and causing the ink to fly. The ink flying means is not particularly limited and may be appropriately selected according to the purpose. Examples thereof include various recording heads (ink discharge heads), and particularly a head having a plurality of nozzle rows and a liquid storage. It is preferable to have a sub-tank that contains the liquid supplied from the tank for supplying the liquid to the head.
The sub tank includes negative pressure generating means for generating a negative pressure in the sub tank, atmospheric release means for releasing the inside of the sub tank to the atmosphere, and detection means for detecting the presence or absence of ink by a difference in electrical resistance. What has is preferable.

  The stimulus can be generated, for example, by the stimulus generating means, and the stimulus is not particularly limited and can be appropriately selected according to the purpose, such as heat (temperature), pressure, vibration, light, etc. Is mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, heat and pressure are preferable.

  Examples of the stimulus generating means include a heating device, a pressurizing device, a piezoelectric element, a vibration generating device, an ultrasonic oscillator, and a light. Specifically, a piezoelectric actuator such as a piezoelectric element, a thermal actuator that uses a phase change caused by film boiling of a liquid using an electrothermal transducer such as a heating resistor, a shape memory alloy actuator that uses a metal phase change caused by a temperature change, For example, an electrostatic actuator using an electrostatic force may be used.

There is no particular limitation on the mode of the ink flying, and it varies depending on the type of the stimulus. For example, using a thermal head or the like, generating bubbles in the ink by the thermal energy, and discharging and ejecting the ink as droplets from the nozzle holes of the recording head by the pressure of the bubbles. It is done. Further, when the stimulus is “pressure”, for example, by applying a voltage to a piezoelectric element bonded to a position called a pressure chamber in an ink flow path in the recording head, the piezoelectric element bends and the volume of the pressure chamber is increased. And a method of ejecting and ejecting the ink as droplets from the nozzle holes of the recording head.
A method in which a voltage is applied to the piezo element to fly ink is preferable. Since the piezo method does not generate heat, it is advantageous for flying ink containing resin, and is an effective method with less nozzle clogging, particularly when ink containing a small amount of wetting agent is used.
In order to prevent nozzle omission, it is preferable to perform a blank scan by applying a voltage having a strength that does not eject ink to the piezo element. Furthermore, it is preferable to perform an operation of discharging ink to the ink reservoir before reaching the empty scan for one page printing.

  Further, it is preferable to have a scraping means for scraping off the ink fixed to the empty discharge receptacle. As the scraping means, either a wiper or a cutter is preferable.

  The control means is not particularly limited as long as the movement of each means can be controlled, and can be appropriately selected according to the purpose. Examples thereof include devices such as sequencers and computers.

  Here, the image recording method of the present invention of FIG. 1 is realized as a method for applying the pretreatment liquid to a recording medium and recording an image with an ink containing a colorant before the pretreatment liquid is dried and solidified. A specific example of the apparatus for this will be described. The example of the pretreatment liquid application apparatus in FIG. 1 is a type of recording apparatus that scans an inkjet recording head to form an image.

  In the pretreatment application and ink jet recording apparatus of FIG. 1, the recording medium 6 is fed by the paper feed roller 7 and the pretreatment liquid 1 filled in the pretreatment liquid container 42 by the application roller 4 and the counter roller 5 is applied to the recording medium. Evenly thinly applied. The pretreatment liquid is pumped by the pumping roller 3 and is uniformly applied to the applying roller 4 by the film thickness control roller 2. The recording medium is fed to a recording scanning unit having the inkjet recording head 20 while being applied with the pretreatment liquid. Since the length of the paper path from the end portion (A portion in FIG. 1) of the pretreatment liquid application operation to the recording scan start portion (B portion in FIG. 1) is set to be longer than the length in the feeding direction of the recording medium. When the medium reaches the recording scan start portion, the application of the pretreatment liquid can be completely completed. In this case, since the pretreatment liquid can be applied before the inkjet recording head 20 starts scanning for printing and the recording medium 6 is intermittently conveyed, the conveyance speed of the recording medium is constant. It can be applied continuously and can be applied uniformly without unevenness. In the example of FIG. 1, the recording medium that requires preprocessing is supplied from the lower cassette, and the recording medium that does not need to be processed is supplied from the upper cassette. It is convenient to provide long.

  FIG. 2 shows another specific example of an apparatus for realizing the image recording method of the present invention. The apparatus example of FIG. 2 is also a type of recording apparatus that scans an inkjet recording head to form an image. This is an example of a compact device configuration compared to the device of FIG. The recording medium 6 is fed out by the paper feed roller 7 and the pretreatment liquid 1 filled in the pretreatment liquid container 42 by the application roller 4 and the counter roller 5 is uniformly and thinly applied to the recording medium. The pretreatment liquid is pumped by the pumping roller 3 and is uniformly applied to the applying roller 4 by the film thickness control roller 2. The recording medium passes through a recording scanning portion of the inkjet recording head 20 while being applied with the pretreatment liquid, and is fed until the paper completes the application of the pretreatment liquid, and again when the paper completes the application of the pretreatment liquid. The head of the sheet is returned until it reaches the recording scan start position. Completion of application can be detected, for example, by providing a known recording medium detection means (not shown) near the exit of the pretreatment liquid application device. This detection means is not always necessary. By inputting information on the length of the recording medium in advance into the controller and controlling the number of rotations of the motor, the feed amount of the outer periphery of the conveyance roller of the recording medium is set to the length of the recording medium. A corresponding system configuration may be adopted.

  The recording medium to which the pretreatment liquid has been applied is transported to the recording scanning position again before the pretreatment liquid is dried and solidified. In this case, the timing is adjusted to the scanning of the ink jet recording head 20. It is conveyed intermittently. When returning the same path as the path sent when returning the recording medium, the trailing edge of the paper enters the pretreatment liquid application device in reverse, causing problems such as uneven coating, dirt, and paper jam. When the direction is changed by the recording medium guide 31. That is, when the recording medium is reversely fed after applying the pretreatment liquid to the recording medium, the recording medium guide 31 is moved to the position of the dotted line in the figure by a known means such as a solenoid or a motor. Thereby, since the recording medium is conveyed to the position of the recording medium guide 34, it is possible to prevent the recording medium from being soiled or jammed.

  The pretreatment liquid application step is preferably performed continuously at a constant linear velocity of 20 to 200 mm / s. For this reason, in this example of the apparatus, when a single-sheet recording medium is used and a certain single-sheet recording medium is viewed, an ink jet recording method is performed after the step of applying the pretreatment liquid to the recording medium is completed for the single-sheet. The process of recording an image is started. As described above, in the apparatus, since the pretreatment liquid application speed and the image recording speed do not match in most cases, the recording start portion and the recording end portion of the single wafer after the pretreatment liquid is applied. There is a difference in the time until the image is recorded. Even when this difference becomes considerably large, it contains a large amount of a hydrophilic solvent having a boiling point higher than that of water and a low evaporation rate, and is close to the amount in equilibrium with the moisture in the air in the environment where the printer is used. In the pretreatment liquid prepared to the moisture ratio, water evaporation from the liquid is remarkably suppressed, so at least visually observe the difference in image quality that occurs between the recording start and recording end of the single-wafer recording medium. It can be reduced below the level that can be achieved.

  As is apparent from the recording medium conveyance process in this apparatus, after the pretreatment liquid is applied, the recording medium to which the pretreatment liquid is applied is a recording medium such as a roller, a roller, or a guide in order to form an image. In many cases, it is necessary to transport the recording medium by means of contact with the recording medium. In such a case, if the pretreatment liquid applied to the recording medium is transferred to the conveyance member of the recording medium, the conveyance function may be impaired or dirt may accumulate, resulting in a decrease in image quality. Cause problems. In order to prevent this problem, measures such as making the guide into corrugated plates, rolling rollers into a spur shape, or using a water-repellent material on the surface of the roller are alleviated from the device side. Can do.

  However, it is essentially important that the pretreatment liquid applied to the recording medium is absorbed into the recording medium as quickly as possible and apparently dried. In order to achieve this object, it is effective to set the surface tension of the pretreatment liquid to 40 mN / m or less so that the liquid can quickly penetrate into the recording medium. “Dry solidification” does not mean that the pretreatment liquid is absorbed into the recording medium as described above, and does not appear to be dry, but the liquid compound in the pretreatment liquid such as moisture evaporates and is liquid. It means that it cannot solidify and solidifies. As described above, the pretreatment liquid according to the present invention is absorbed by the recording medium and apparently dried by using the recording apparatus in which the pretreatment applying apparatus and the image recording apparatus are set as described above. Even in this case, ink jet recording can be performed in a state where the pretreatment liquid is not solidified, and the image quality can be remarkably improved even when the amount of the pretreatment liquid applied is extremely small.

  3 and 4 show examples of sequences for controlling the operation of the apparatus as shown in FIGS. When receiving a print command from a host machine such as a personal computer, the preprocessing application / image recording apparatus starts a head cleaning operation and a pretreatment liquid application operation simultaneously, and starts a recording operation when all the preparations are completed. In this case, the image data may be transferred for one scan, for a plurality of scans, or for one page. Head cleaning and ejection check operations are not always necessary. In addition, it is not necessary to perform head cleaning, ejection check operation and image data processing / image data transfer sequentially. Parallel processing such as pretreatment liquid application, head cleaning, ejection check operation and image data processing / image data transfer is started simultaneously. Can be processed. In this way, the pre-treatment liquid application, the head cleaning, the ejection check operation and the image data processing / image data transfer are processed in parallel, so that the throughput of the print recording apparatus can be reduced even when the pre-treatment liquid application work is performed. It is possible to record an image without dropping it.

  As a means for forming an image by applying a pretreatment liquid to a recording medium in the image recording method of the present invention and then depositing the ink as droplets on the recording medium, any known ink jet recording method can be applied. In the example of the apparatus shown in FIGS. 1 and 2, an example of an ink jet recording method of scanning a head has been shown. However, by using a lined head, pretreatment liquid can be applied to a single sheet of recording medium. Image recording can be performed at the same speed at the same time.

  After applying the pretreatment liquid to the recording medium in the present invention, an ink jet recording method is preferable as a method of adhering the ink to the recording medium as droplets. PZT or the like is used regardless of the recording head driving method. An on-demand type head using a piezoelectric element actuator, a method of applying thermal energy, an actuator using electrostatic force, or the like can be used, or recording can be performed with a continuous jet type charge control type head. In the method of applying thermal energy, it is difficult to freely control the ejection of droplets, and there is a tendency for variations in the image due to the type of recording medium, etc., but the pretreatment liquid is applied to the recording medium. By providing these, these problems can be solved, and stable high image quality can be obtained regardless of the type of recording medium.

  Here, one aspect of carrying out the ink jet recording method of the present invention by the ink jet recording apparatus of the present invention will be described with reference to the drawings. FIG. 3 is a schematic view showing an example of the serial type ink jet recording apparatus of the present invention. The ink jet recording apparatus shown in FIG. 3 stocks an apparatus main body 101, a paper feed tray 102 for loading paper mounted on the apparatus main body 101, and paper on which an image is recorded (formed) mounted on the apparatus main body 101. A paper discharge tray 103 and an ink cartridge loading unit 104. On the upper surface of the ink cartridge loading unit 104, an operation unit 105 such as operation keys and a display is arranged. The ink cartridge loading unit 104 has a front cover 115 that can be opened and closed for attaching and detaching the ink cartridge 201.

In the apparatus main body 101, as shown in FIGS. 4 and 5, a carriage 133 is slid in the main scanning direction by a guide rod 131 and a stay 132, which are guide members horizontally mounted on left and right side plates (not shown). The main scanning motor (not shown) moves and scans in the direction of the arrow in FIG.
The carriage 133 is provided with a recording head 134 composed of four ink jet recording heads that eject ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (Bk). Are arranged in a direction crossing the main scanning direction, and the ink droplet ejection direction is directed downward.
As the ink jet recording head constituting the recording head 134, a piezoelectric actuator such as a piezoelectric element, a thermal actuator using phase change due to liquid film boiling using an electrothermal transducer such as a heating resistor, a metal phase due to temperature change, and the like. A shape memory alloy actuator using change, an electrostatic actuator using electrostatic force, or the like provided as energy generating means for discharging ink can be used.

In addition, the carriage 133 is equipped with a sub tank 135 for each color for supplying ink of each color to the recording head 134. The sub tank 135 is supplied with the ink from the ink cartridge 201 of the present invention loaded in the ink cartridge loading unit 105 via an ink supply tube (not shown) and is replenished.
On the other hand, as a paper feeding unit for feeding the paper 142 stacked on the paper stacking unit (pressure plate) 141 of the paper feeding tray 102, a half-moon roller (feeding) that separates and feeds the paper 142 from the paper stacking unit 141 one by one. A separation pad 144 made of a material having a large coefficient of friction is provided facing the paper roller 143) and the paper feed roller 143, and the separation pad 144 is urged toward the paper feed roller 143 side.
As a transport unit for transporting the paper 142 fed from the paper feed unit below the recording head 134, a transport belt 151 for transporting the paper 142 by electrostatic adsorption and a guide 145 from the paper feed unit. The counter roller 152 for transporting the paper 142 fed via the transport belt 151 with the transport belt 151 and the paper 142 fed substantially vertically upward are changed by approximately 90 ° so as to follow the transport belt 151. For this purpose, a conveyance guide 153 and a tip pressure roller 155 urged toward the conveyance belt 151 by a pressing member 154 are provided. In addition, a charging roller 156 that is a charging unit for charging the surface of the conveyance belt 151 is provided.
The conveyance belt 151 is an endless belt, is stretched between the conveyance roller 157 and the tension roller 158, and can circulate in the belt conveyance direction. The transport belt 151 includes, for example, a surface layer serving as a sheet adsorbing surface formed of a resin material having a thickness of about 40 μm that is not subjected to resistance control, for example, a copolymer of tetrafluoroethylene and ethylene (ETFE), and the surface layer. It has a back layer (medium resistance layer, earth layer) that is made of the same material and has resistance controlled by carbon. On the back side of the conveyance belt 151, a guide member 161 is arranged corresponding to a printing area by the recording head 134. Note that, as a paper discharge unit for discharging the paper 142 recorded by the recording head 134, a separation claw 171 for separating the paper 142 from the conveyance belt 151, a paper discharge roller 172, and a paper discharge roller 173 are provided. The paper discharge tray 103 is disposed below the paper discharge roller 172.

A double-sided paper feeding unit 181 is detachably mounted on the back surface of the apparatus main body 101. The double-sided paper feeding unit 181 takes in the paper 142 returned by the reverse rotation of the transport belt 151, reverses it, and feeds it again between the counter roller 152 and the transport belt 151. A manual paper feed unit 182 is provided on the upper surface of the duplex paper feed unit 181.
In this ink jet recording apparatus, the paper 142 is separated and fed one by one from the paper feed unit, and the paper 142 fed substantially vertically upward is guided by the guide 145 and between the transport belt 151 and the counter roller 152. It is sandwiched and conveyed. Further, the leading end is guided by the conveying guide 153 and pressed against the conveying belt 151 by the leading end pressure roller 155, and the conveying direction is changed by approximately 90 °.
At this time, the conveyance belt 157 is charged by the charging roller 156, and the sheet 142 is conveyed by being electrostatically attracted to the conveyance belt 151. Therefore, by driving the recording head 134 according to the image signal while moving the carriage 133, ink droplets are ejected onto the stopped paper 142 to record one line, and after the paper 142 is conveyed by a predetermined amount, Record the next line. Upon receiving a recording end signal or a signal that the trailing edge of the sheet 142 has reached the recording area, the recording operation is terminated and the sheet 142 is discharged onto the discharge tray 103.
When a near-end remaining amount of ink in the sub tank 135 is detected, a required amount of ink is supplied from the ink cartridge 201 to the sub tank 135.

  In this ink jet recording apparatus, when the ink in the ink cartridge 201 of the present invention is used up, the casing of the ink cartridge 201 can be disassembled and only the ink bag inside can be replaced. Further, the ink cartridge 201 can supply ink stably even when the ink cartridge 201 is placed vertically and has a front loading configuration. Therefore, even when the upper portion of the apparatus main body 101 is closed and installed, for example, when stored in a rack or when an object is placed on the upper surface of the apparatus main body 101, the ink cartridge 201 is used. Can be easily exchanged.

  In addition, although it demonstrated in the example applied to the serial type (shuttle type) inkjet recording device which a carriage scans, it can apply similarly to the line type inkjet recording device provided with the line type head.

  The ink jet recording apparatus and the ink jet recording method of the present invention can be applied to various types of recording by the ink jet recording method, and are particularly suitable for, for example, an ink jet recording printer, a facsimile apparatus, a copying apparatus, and a printer / fax / copier multifunction machine. Can be applied to.

(Ink record)
The ink recorded matter recorded by the ink jet recording method of the present invention is the ink recorded matter of the present invention. The ink recorded matter of the present invention has an image formed on the recording medium using the ink in the ink media set of the present invention.
The recording medium is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include plain paper, coated paper for printing, glossy paper, special paper, cloth, film, and OHP sheet. Can be mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, at least one of plain paper and coated paper for printing is preferable.
The plain paper is advantageous in that it is inexpensive. The coated paper for printing is advantageous in that it provides a smooth glossy image that is relatively inexpensive and glossy. However, although the drying property is poor and it is generally difficult to use for inkjet, the drying property is improved by the ink of the present invention.
The ink recorded matter has high image quality, no bleeding, excellent temporal stability, and can be suitably used for various purposes as a material on which various prints or images are recorded.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

(Production Example 1)
-Production of cyan ink-
An ink composition having the following formulation was prepared and the pH was adjusted, followed by filtration with a membrane filter having an average pore diameter of 5 μm to produce an ink.
<Cyan ink composition>
・ C. I. Acid Blue 9 ... 4% by mass
Acrylic silicone emulsion [solid content 40% by mass, residual water, volume average particle size 150 nm, glass transition temperature of resin component -15 ° C. (differential rise) to −6 ° C. (inflection point)] 60% by mass
・ Glycerin as wetting agent: 6% by mass
・ 1,3-butanediol as a wetting agent: 18% by mass
・ 2-Ethyl-1,3-hexanediol as penetrant 2 mass%
・ Fluorine-based surfactant (fluorine-substituted carbon number 4-16): 2.5% by mass
-Antiseptic / antifungal agent ... 0.05% by mass
・ Amine organic pH adjuster ... 1.1% by mass
・ Silicone emulsion antifoaming agent: 0.1% by mass
-Water ... balance The total content of the colorant and the water-dispersible resin in the obtained ink is 28% by mass, and the content of the water-dispersible resin relative to the total content of the colorant and the water-dispersible resin is It was 86 mass%.

(Production Example 2)
-Magenta ink production-
An ink composition having the following formulation was prepared and the pH was adjusted, followed by filtration with a membrane filter having an average pore diameter of 5 μm to produce an ink.
<Magenta ink composition>
・ C. I. Acid Red 52 ... 4% by mass
Acrylic silicone emulsion [solid content 40% by mass, residual water, volume average particle size 150 nm, glass transition temperature of resin component -15 ° C. (differential rise) to −6 ° C. (inflection point)] 60% by mass
・ Glycerin as wetting agent: 6% by mass
・ 1,3-butanediol as a wetting agent: 18% by mass
・ 2-Ethyl-1,3-hexanediol as penetrant 2 mass%
・ Fluorine-based surfactant (fluorine-substituted carbon number 4-16): 2.5% by mass
-Antiseptic / antifungal agent ... 0.05% by mass
・ Amine organic pH adjuster ... 1.1% by mass
・ Silicone emulsion antifoaming agent: 0.1% by mass
-Water ... balance The total content of the colorant and the water-dispersible resin in the obtained ink is 28% by mass, and the content of the water-dispersible resin relative to the total content of the colorant and the water-dispersible resin is It was 86 mass%.

(Production Example 3)
-Preparation of yellow ink-
An ink composition having the following formulation was prepared and the pH was adjusted, followed by filtration with a membrane filter having an average pore diameter of 5 μm to produce an ink.
<Yellow ink composition>
・ C. I. Acid Yellow 23 ... 2% by mass
Acrylic silicone emulsion [solid content 40% by mass, residual water, volume average particle size 150 nm, glass transition temperature of resin component -15 ° C (differential rise) to -6 ° C (inflection point)] ... 30% by mass
・ Glycerin as wetting agent: 6% by mass
・ 1,3-butanediol as a wetting agent: 18% by mass
・ 2-Ethyl-1,3-hexanediol as penetrant 2 mass%
・ Fluorine-based surfactant (fluorine-substituted carbon number 4-16): 2.5% by mass
-Antiseptic / antifungal agent ... 0.05% by mass
・ Amine organic pH adjuster ... 1.1% by mass
・ Silicone emulsion antifoaming agent: 0.1% by mass
-Water ... balance The total content of the colorant and the water-dispersible resin in the obtained ink is 14% by mass, and the content of the water-dispersible resin relative to the total content of the colorant and the water-dispersible resin is It was 86 mass%.

(Production Example 4)
-Preparation of black ink-
An ink composition having the following formulation was prepared and the pH was adjusted, followed by filtration with a membrane filter having an average pore diameter of 0.8 μm to produce an ink.
<Black ink composition>
-Carbon black dispersion having a hydrophilic group (solid content 20% by mass, the rest is water, colorant / resin (mass ratio) in the solid content = 10/0) ... 30% by mass
Acrylic silicone emulsion [solid content 40% by mass, residual water, volume average particle size 150 nm, glass transition temperature of resin component -15 ° C. (differential rise) to −6 ° C. (inflection point)] 45% by mass
・ 1,3-butanediol as a wetting agent: 2% by mass
・ 2-Pyrrolidone as a wetting agent: 2% by mass
・ 2-Ethyl-1,3-hexanediol as penetrant 2 mass%
・ Fluorine-based surfactant (fluorine-substituted carbon number 4-16): 1% by mass
-Antiseptic / antifungal agent ... 0.05% by mass
・ Stabilizer: 0.0005% by mass
・ Organic pH adjuster (2 types) ... 0.65 mass%
・ Silicone emulsion antifoaming agent: 0.1% by mass
-Water ... balance The total content of the colorant and the water-dispersible resin in the obtained ink is 24% by mass, and the content of the water-dispersible resin relative to the total content of the colorant and the water-dispersible resin is It was 75 mass%.

  Next, the surface tension, pH, and viscosity of each of the obtained inks of Production Examples 1 to 4 were measured as follows. The results are shown in Table 1.

<Measurement of pH>
The pH was measured at 23 ° C. using a pH meter (MODEL HM3A, manufactured by Toa Denpa Kogyo Co., Ltd.).

<Measurement of viscosity>
The viscosity was measured at 25 ° C. using a RE500 viscometer (manufactured by Toki Sangyo Co., Ltd.) under conditions of cone 34 × R24, 180 rpm, 3 minutes later.

<Measurement of surface tension>
The surface tension is a static surface tension measured at 25 ° C. using a platinum plate using a surface tension measuring device (CBVP-Z, manufactured by Kyowa Interface Science Co., Ltd.).

(Production Example 5)
<Preparation of pretreatment liquid 1>
The following composition was mixed and stirred to prepare a pretreatment liquid 1 for recording media, and adjusted with triethanolamine so that the pH was 7.
[Composition of pretreatment liquid 1]
-Cationic polymer represented by the following structural formula (2) (dicyandiamide resin, mass average molecular weight 7,000): 25% by mass
However, in said structural formula (2), n represents the number of polymerization.
-Cationic monomer compound C-1 represented by the following structural formula (counter ion is chlorine ion) 2 mass%
・ Glycerin: 25% by mass
・ Ethylene glycol: 30% by mass
・ Sodium benzoate: 1% by mass
-Ion-exchanged water ... remaining amount When the viscosity of the obtained pretreatment liquid 1 was measured with a B-type rotational viscometer manufactured by Tokyo Keiki Co., Ltd., it was 1,270 mPa · s (25 ° C).

(Production Example 6)
<Preparation of pretreatment liquid 2>
The following composition was mixed and stirred to prepare a pretreatment liquid 2 for recording media, and adjusted with triethanolamine so that the pH was 7.
[Composition of pretreatment liquid 2]
-Cationic polymer represented by the following structural formula: 15% by mass
However, in said structural formula, X < ^- > represents a chlorine ion, and a mass average molecular weight is 3,500. Cationic monomer compound C-3 represented by the following structural formula (counter ion is a chlorine ion) 3 mass%
・ Glycerin 20% by mass
・ N-methyl-2-pyrrolidone: 20% by mass
・ 1,6-hexanediol: 15% by mass
・ Sodium dehydroacetate: 1% by mass
It was 850 mPa * s (25 degreeC) when the viscosity of the obtained pretreatment liquid 2 was measured with the Tokyo Keiki Co., Ltd. B type rotational viscometer.

<Recording paper 1>
Commercial gloss paper (Oji Paper Co., Ltd., POD gloss coat 100 g / m ² paper)

  The recording paper 1 was measured for the amount of pure water transferred and the critical surface tension (γc) as follows. The results are shown in Table 2.

<Measurement of the amount of pure water transferred by dynamic scanning absorption meter>
The recording paper 1 was measured for pure water absorption curve using a dynamic scanning absorption meter (model: KS350D, manufactured by Kyowa Seiko Co., Ltd.). The absorption curve was plotted with a transition amount (mL / m ² ) and a square root of contact time √ (ms) to make a straight line with a certain slope, and the value of the transition amount after a certain time was measured by interpolation.

<Critical surface tension (γc)>
The critical surface tension (γc) is a wetting tension test solution with various surface tensions based on JIS-K6768, 1999 “Plastic-film and sheet-wetting tension test method” (mixed solution of ethylene glycol monoethyl ether and formamide). 4 microliters (μl) of droplets were dropped on the media printing surface, and a contact angle measurement device (OCA, manufactured by Data Physics Co., Ltd.) was used to capture the contact angle of each droplet when moving 0.5 seconds. The Zisman Plot was created from the contact angle.

<Applying pretreatment liquid>
When the pretreatment liquids 1 and 2 are filled in the pretreatment liquid container 42 of the image recording apparatus shown in FIG. 1 and applied to the recording paper 1 at a linear velocity of 85 mm / s, 2.8 to 3.2 g / m ^2. It was the amount of adhesion.

Example 1
-Ink set, recording medium, pretreatment liquid, and image recording-
An ink set 1 comprising the cyan ink of Production Example 1, the magenta ink of Production Example 2, the yellow ink of Production Example 3, and the black ink of Production Example 4 was prepared by a conventional method.
Using the obtained ink set 1 and recording paper 1 as a recording medium, after applying the pretreatment liquid 1 as described above, printing was performed with an ink jet printer (G707, manufactured by Ricoh Co., Ltd.).
As a result, an image having almost no color stain even when rubbed within 1 minute after printing and having almost no problem in drying time was obtained. Further, the obtained image had a high image density and was clear and close to a printed matter.
In addition, when plain paper (T6200 paper, manufactured by Ricoh Co., Ltd.) was used instead of the recording paper 1, an image without bleeding through, high image density, and good color even without plain paper was obtained. It was.

(Example 2)
-Ink set, recording medium, pretreatment liquid, and image recording-
In Example 1, printing was performed in the same manner as in Example 1 except that the pretreatment liquid 2 was used as the pretreatment liquid. As a result, an image having almost no color stain even when rubbed within 1 minute after printing and having almost no problem in drying time was obtained. Further, the obtained image had a high image density and was clear and close to a printed matter.

(Comparative Example 1)
In Example 1, printing was performed in the same manner as in Example 1 except that the pretreatment liquid 1 was not applied to the recording medium. As a result, the colorant of the ink sank in the coating layer, and the image density was low and an unclear image was obtained.

The ink media set of the present invention has a problem of drying speed on a smooth printing paper having a low water absorption capacity, and can produce a clear and high-quality image close to printed matter. It can be suitably used for a recorded material, an ink jet recording method, and an ink jet recording apparatus.
The ink jet recording apparatus and the ink jet recording method of the present invention can be applied to various types of recording by the ink jet recording method, and are particularly suitable for, for example, an ink jet recording printer, a facsimile apparatus, a copying apparatus, and a printer / fax / copier multifunction machine. Can be applied to.

FIG. 1 is a side sectional view showing an example of a pretreatment liquid coating apparatus in the ink jet recording apparatus of the present invention. FIG. 2 is a side sectional view of an apparatus showing another example of the pretreatment liquid coating apparatus in the ink jet recording apparatus of the present invention. FIG. 3 is a sequence diagram showing an example of an embodiment of the present invention. FIG. 4 is a sequence diagram showing an example of another embodiment of the present invention. FIG. 5 is a schematic view showing an example of the ink cartridge and the pretreatment liquid cartridge of the present invention. FIG. 6 is a schematic view including the case (exterior) of the ink cartridge and the pretreatment liquid cartridge of FIG. FIG. 7 is an explanatory perspective view of a state where the cover of the ink cartridge loading unit of the ink jet recording apparatus is opened. FIG. 8 is a schematic configuration diagram illustrating the overall configuration of the inkjet recording apparatus. FIG. 9 is a schematic enlarged view showing an example of an ink jet head in the ink jet recording apparatus of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pretreatment liquid 2 Film thickness control roller 3 Pumping roller 4 Application roller 5 Counter roller 6 Paper 7 Paper feed roller 8 Paper feed tray 11, 12, 14, 13, 15, 16 Paper feed roller 17 Paper 18 Paper feed roller 20 Recording head 21 Ink Cartridge 22 Carriage Shaft 23 Carriage 31 Paper Guide 33 Paper Feed Roller 34 Paper Return Guide 42 Pretreatment Liquid Container 10 Frame 20 Channel Plate 30 Nozzle Plate 40 Base 50 Multilayer Piezoelectric Element 60 Vibration Plate 70 Adhesive Layer 101 Device Main Body 102 Paper Feed Tray 103 Discharge tray 104 Ink cartridge loading unit 111 Upper cover 112 Front surface 115 Front cover 131 Guide rod 132 Stay 133 Carriage 134 Recording head 135 Sub tank 141 Paper placement unit 142 Paper 144 Separation pad 151 Conveying belt 152 Counter roller 156 Charging roller 157 Conveying roller 158 Densation roller 171 Separating claw 172 Discharging roller 173 Discharging roller 181 Double-sided paper feeding unit 201 Ink cartridge 241 Ink bag 242 Ink inlet 243 Ink discharging port 244 Cartridge exterior

Claims (23)

An ink containing at least a colorant, a water-dispersible resin, and water;
A recording medium having a support and at least a coating layer on the support;
A pretreatment liquid applied to the recording surface of the recording medium during inkjet recording, and an ink media set having
The total content of the colorant and the water-dispersible resin in the ink is 10 to 35% by mass, and the content of the water-dispersible resin with respect to the total content is 70 to 95% by mass,
The pretreatment liquid contains 10 to 80% by mass of an ink fixing assistant that reduces at least one of ink dispersibility and solubility, and has a viscosity at 25 ° C. of 100 to 10,000 mPa · s. Ink media set characterized by being.   The ink media set according to claim 1, wherein the ink fixing aid is a cationic compound.   The ink media set according to claim 2, wherein the cationic compound is a cationic polymer. The ink media set according to claim 3, wherein the cationic polymer is at least one selected from polymers represented by the following structural formulas (1) to (20).
However, in said structural formula (1), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. R represents an alkylene group having 1 to 3 carbon atoms. n represents the number of polymerizations.
However, in said structural formula (2), n represents the number of polymerization.
However, in the structural formula (3), X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. R ₁ represents either a hydrogen atom or CH ₃ . R ₂ , R ₃ , and R ₄ may be the same as or different from each other, and represent either a hydrogen atom or an alkyl group. n represents the number of polymerizations.
However, in said structural formula (4), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (5), n represents the natural number of 5-30.
However, in said structural formula (6), n represents the number of polymerization.
However, in the structural formula (7), X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (8), n represents the number of polymerization.
However, the structural formula (9), Z and Y each represent -OCOCH ₃ or -OH. R ₅ represents an alkylene group having 1 to 4 carbon atoms. n, l, and m each represent the number of polymerizations.
However, in the structural formula (10), R ₆ represents an alkyl group. X ⁻ represents an anion selected from a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in the structural formula (11), R ⁷ and R ⁸ may be the same as or different from each other, and represent either a hydrogen atom or an alkyl group. X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (12), X < ^- > represents the anion in any one of a halogen ion, nitrate ion, nitrite ion, and acetate ion. n represents the number of polymerizations.
However, in said structural formula (13), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (14), j and k represent a natural number of 2-6, respectively. n represents the number of polymerizations.
However, in the structural formula (15), X ⁻ represents an anion of any one of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (16), X < ^- > represents the anion in any one of a halogen ion, nitrate ion, nitrite ion, and acetate ion. Q represents a copolymerizable monomer component. n and m each represent the number of polymerizations.
However, in said structural formula (17), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in said structural formula (18), X < ^- > represents any anion of a halogen ion, a nitrate ion, a nitrite ion, and an acetate ion. n represents the number of polymerizations.
However, in the structural formulas (19) and (20), D ¹ represents a substituent represented by any of the following structural formulas (21) and (22). D ² is independent of D ¹ and represents any one of a hydrogen atom, the following structural formula (21), and the following structural formula (22). n represents a natural number, m represents an integer of 0 or more
However, in the structural formula (21) and the structural formula (22), R ₉ and R ₁₀ may be the same as or different from each other, and are either a hydrogen atom, an alkyl group, or an aryl group. Represents. R ₁₁ and R ₁₂ may be the same as or different from each other, and each represents a hydrogen atom, an alkali metal, or a substituent represented by the following structural formula (23).
However, in the structural formula (23), R _{13 to} R ₁₆ may be the same as or different from each other, and are any of a hydrogen atom, an alkyl group, an aryl group, a hydroxyalkyl group, and a benzyl group. Represents   The ink media set according to claim 2, wherein the cationic compound is particles and is dispersed in the pretreatment liquid.   The ink media set according to claim 5, wherein the particles are cationic silica particles.   The ink media set according to claim 5, wherein the cationic compound is a cationic emulsion.   The ink media set according to claim 1, wherein the ink fixing aid is a water-soluble polyvalent metal salt.   The ink media set according to any one of claims 1 to 8, wherein a critical surface tension based on JIS K6768 on the recording surface of the recording medium is 25 to 40 mN / m. The recording surface of the pure water recording medium at a contact time of 100 ms measured with a dynamic scanning absorption meter has a transfer amount of pure water to the recording surface of ² to 35 ml / m ² and the contact time of 400 ms. the ink media set according to any of claims 1-9 transition amount is 3~40ml / ^{m 2} to.   The ink media set according to any one of claims 1 to 10, wherein the coating layer in the recording medium contains a pigment, and the pigment is at least one selected from kaolin, talc and calcium carbonate.   The ink media set according to any one of claims 1 to 11, wherein the colorant in the ink is an anionic dye.   The ink media set according to any one of claims 1 to 12, wherein the water-dispersible resin contains resin fine particles, the resin fine particles are acrylic silicone resin fine particles, and the glass transition temperature of the acrylic silicone resin is 25 ° C or lower. .   The ink media set according to claim 13, wherein the volume average particle diameter of the resin fine particles in the resin emulsion is 10 to 1,000 nm.   An ink cartridge comprising the ink in the ink media set according to claim 1 contained in a container.   15. A pretreatment liquid cartridge comprising: a pretreatment liquid in the ink media set according to claim 1 contained in a container. An ink jet recording method using the ink media set according to claim 1,
Applying a pretreatment liquid to the recording surface of the recording medium;
And a step of applying a stimulus to the ink in accordance with an image signal before the pretreatment liquid dries and causing the ink to fly to record an image on a recording medium.   The inkjet recording method according to claim 17, wherein the pretreatment liquid is applied by a roller. The inkjet recording method according to any one of claims 17 to 18, wherein the adhesion amount of the pretreatment liquid is 0.5 to 10 g / m ² in solid content on the recording surface of the recording medium.   The inkjet recording method according to claim 17, wherein the stimulus is at least one selected from heat, pressure, vibration, and light. An ink jet recording apparatus using the ink media set according to claim 1,
Means for applying a pretreatment liquid to the recording surface of the recording medium;
An ink jet recording apparatus comprising: means for applying a stimulus to an ink in accordance with an image signal before the pretreatment liquid dries, and causing the ink to fly to record an image on a recording medium.   The inkjet recording apparatus according to claim 21, wherein the stimulus is at least one selected from heat, pressure, vibration, and light. An ink recorded matter comprising an image formed by using an ink on a recording medium to which a pretreatment liquid has been applied using the ink media set according to claim 1.