JP2015039809A - Image recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image that has high resolution and high concentration, and excellent homogeneity of a solid image part.SOLUTION: An image recording method has following steps in this order: of giving a process liquid comprising silica particles to a recording medium; giving a reaction liquid for the agglomeration or deposition of a colorant in ink to the recording medium; and giving the ink comprising the colorant to the recording medium.

Description

  The present invention relates to an image recording method.

  In order to obtain a high-resolution, high-density, blur-free image, an image recording method using ink that suppresses penetration into the recording medium and spread on the recording medium is effective. However, on the other hand, since the drying speed of the ink is low, when high-speed printing is performed, if the recording medium overlaps on the tray after printing, a problem such that the undried ink is offset to the overlapping recording medium easily occurs. . In addition, when performing double-sided printing on a recording medium, undried ink may contaminate the inside of the printer such as a transport roller.

  Therefore, as a technique for achieving both high image quality and quick drying, there is a so-called two-liquid printing method that uses a reaction liquid mainly for the purpose of further improving image quality in addition to ink. In the reaction liquid used in the two-liquid printing method, generally, a component that promotes aggregation of a coloring material in ink is added. For example, a two-component printing method using an agglutination reaction by contact between an ink containing an anionic substance and a reaction solution containing a polyvalent metal ion can be mentioned. Moreover, the method of aggregating an ink with the reaction liquid containing the cationic water-soluble resin which consists of polyallylamine / polyvinylamine can be mentioned. Such a two-liquid printing method is generally characterized in that an image with high resolution, high image density, and less bleeding can be obtained as compared with a printing method using only conventional ink.

  For the purpose of improving the image quality, a method of applying a hydrophilic treatment liquid such as a surfactant or a penetrating solvent to a recording medium has been proposed.

  Further, a proposal has been made to suppress the set-off of the printed matter by providing a device for promoting water absorption of the recording medium before applying the reaction liquid. (Patent Document 1)

JP 2010-188568 A

  As a result of detailed examination of the above-mentioned technique by the present inventors, even when a hydrophilic treatment liquid such as a surfactant or a permeable solvent is applied to the recording medium, the uniformity of the solid image portion may not be improved. I understood. Further, when a hydrophilic treatment section such as a plasma irradiation device for a recording medium, a corona discharge device, a charging roller device or the like is provided in the recording device, the device becomes large and power consumption becomes large.

  Thus, as a result of intensive studies by the present inventors, it was discovered that a liquid containing silica particles that make the surface of the recording medium hydrophilic may be applied before the reaction liquid is applied to the recording medium. Further, it has been found that the reaction liquid can be present on the recording medium in a more uniform state, and an image with excellent uniformity of the solid image portion can be provided by forming an image on the recording medium with ink.

  That is, an object of the present invention is to provide an image recording method that provides an image with high resolution, high density, and excellent uniformity of a solid image portion.

One embodiment is:
Applying a treatment liquid containing silica particles to the recording medium;
Providing the recording medium with a reaction liquid for aggregating or precipitating the coloring material contained in the ink;
And a step of applying an ink containing a coloring material to the recording medium in this order.

  It is possible to provide an image with high resolution, high density and excellent uniformity in the solid image portion.

  In the image recording method of one embodiment of the present invention, a treatment liquid containing silica particles is applied to a recording medium, and then a reaction liquid for aggregating or precipitating the color material contained in the ink is applied to the recording medium. Next, an ink containing a color material is applied to the recording medium. As a result, it is possible to provide an image with high resolution, high density, and excellent uniformity of the solid image portion.

The present inventor presumes the reason why an image having high resolution, high density, and excellent uniformity in the solid image portion was obtained in the above configuration.
First, a treatment liquid containing silica particles is applied to the recording medium. This treatment liquid hydrophilizes the surface of the recording medium and forms a state in which the reaction liquid easily spreads. Next, since the reaction solution is applied thereon, it is considered that the reaction solution is spread. Thereafter, since the ink containing the coloring material is applied onto the recording medium, every ink droplet comes into contact with the same amount of the reaction liquid. As a result, it is considered that an image having high resolution, high density and excellent uniformity of the solid image portion is formed. That is, in one embodiment, since silica particles are contained in the treatment liquid, the silica particles remain on the surface of the recording medium even after the treatment liquid is applied, and the reaction liquid is spread in the lateral direction (the surface direction of the recording medium). I think we can do it.

  On the other hand, when a surfactant or a permeable solvent is used instead of the treatment liquid containing silica particles as in the prior art, a uniform solid image with high resolution and high density cannot be formed. The reason for this is that since the surfactant and the permeable solvent are composed only of liquid components, the reaction liquid has a stronger action of promoting the penetration of the reaction liquid in the thickness direction of the recording medium than the effect of spreading the reaction liquid on the surface of the recording medium. This is thought to be because the film does not spread uniformly. Therefore, it is considered that when ink is applied thereto, the amount of the reaction liquid that can come into contact with the ink droplets varies, and a uniform solid image cannot be formed.

  The recording medium is preferably cast-coated paper. Cast coated paper has a characteristic that the solid image portion is likely to be non-uniform because the ink hardly penetrates. Therefore, by applying the image recording method of the present embodiment to cast coated paper, the effect of the present invention of forming a uniform solid image with high resolution and high density can be exhibited more remarkably. Examples of cast-coated paper include the espricoat series (manufactured by Nippon Paper Industries Co., Ltd.) and the mirror coat series (manufactured by Oji Paper Co., Ltd.).

  Next, each step of the image recording method according to an embodiment of the present invention and each material used will be described below.

(Processing liquid)
The treatment liquid is not particularly limited as long as it contains silica particles, and examples thereof include those containing silica particles dispersed in alcohols or water, which are used as hydrophilic agents. Preferably, the surface of the silica particles is covered with a hydroxyl group in order to develop hydrophilicity. Specific examples of treatment liquids include Super Glass Barrier (Sketch), Platinum Antifouling Coat (Sketch), Super Clear Vision (Sketch), Glass Barrier SAg (Sketch), Snowtex OXS (Nissan) Chemical Industries), Snowtex OS (Nissan Chemical Industries), Snowtex C (Nissan Chemical Industries), Snowtex O-40 (Nissan Chemical Industries), Quartron PL-1 (Fuso Chemical Industries) Etc.) are preferably used. In order not to impair the texture of the recording medium, the volume average particle diameter of the silica particles is preferably 1 nm to 50 nm. Further, the content of the silica particles in the treatment liquid is preferably 0.5% by mass or more and 5% by mass.

(Aqueous medium)
Examples of the aqueous medium used in the treatment liquid include water or a mixed solvent of water and a water-soluble organic solvent. As the water-soluble organic solvent, those having an effect of preventing the reaction solution from drying are particularly preferable. Specifically, the following can be mentioned, for example.
C1-C4 alkyl alcohols, such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol.
Amides such as dimethylformamide and dimethylacetamide.
Ketones or ketoalcohols such as acetone and diacetone alcohol.
Ethers such as tetrahydrofuran and dioxane.
Polyalkylene glycols such as polyethylene glycol and polypropylene glycol.
Alkylene glycols in which the alkylene group contains 2 to 6 carbon atoms;
Alkylene glycols such as ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexylene glycol, and diethylene glycol;
Lower alkyl ether acetates such as polyethylene glycol monomethyl ether acetate.
Glycerin.
Lower alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl (or ethyl) ether, diethylene glycol methyl (or ethyl) ether, triethylene glycol monomethyl (or ethyl) ether.
Polyhydric alcohols such as trimethylolpropane and trimethylolethane.
N-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone.

  The above water-soluble organic solvents can be used alone or as a mixture. It is desirable to use deionized water as the water. In addition to the above components, surfactants, antifoaming agents, antiseptics, antifungal agents, and the like can be added to obtain a treatment liquid having desired physical properties as required.

(Application of treatment liquid)
A treatment liquid is applied on the recording medium. As a method for applying the treatment liquid, an inkjet method using an inkjet device is suitable from the viewpoint of adaptability to various recording medium types (paper types), stability of the applied amount, and control of the applied amount. As the ink jet device applied to the present embodiment, for example, any of various ink jet devices proposed in the ink jet liquid discharge technology such as the following forms can be used.
-A mode in which ink is ejected by forming bubbles by causing film boiling in the ink by the electro-thermal converter,
-A mode in which ink is ejected by an electro-mechanical converter,
-A mode of discharging ink using static electricity.
Among these, those using an electro-thermal converter are preferably used from the viewpoint of high-speed and high-density printing.

  Moreover, there is no restriction | limiting in particular as a form of the whole inkjet device. An ink jet head in the form of a line head in which ink discharge ports are arranged in the traveling direction of the recording medium (in the axial direction when a drum-shaped transfer member is used) can be used. In addition, a shuttle-type head that performs recording while scanning the head perpendicular to the traveling direction of the recording medium can also be used.

In addition, a preferable application amount of the treatment liquid is preferably 0.8 g / m ² or more and 8 g / m ² or less. If the amount of treatment liquid applied is small, the recording medium is not sufficiently hydrophilized, and the solid image portion may not be uniform. On the other hand, if the amount of treatment liquid applied is too large, cockling or curling tends to occur.

(Reaction solution)
The reaction liquid used in this embodiment is one that aggregates or precipitates the color material contained in the ink. The component of the reaction solution is not particularly limited as long as the color material is aggregated or precipitated, but a metal salt or an organic acid is preferable. Further, in consideration of the scratch resistance of the printed matter, a resin may be added to the reaction solution.

Examples of the metal salt that can be used in the reaction solution include divalent or higher polyvalent metal ions and anions that bind to these polyvalent metal ions, and are soluble in water. Specific examples of the polyvalent metal ion include divalent metal ions such as Ca ²⁺ , Cu ²⁺ , Ni ²⁺ , Mg ²⁺ , Zn ²⁺ , and Ba ²⁺ . Other than these, trivalent metal ions such as Al ³⁺ , Fe ³⁺ , Cr ³⁺ , and Y ³⁺ can be mentioned, but are not limited thereto.

  Examples of organic acids include oxalic acid, polyacrylic acid, formic acid, acetic acid, propionic acid, glycolic acid, malonic acid, malic acid, maleic acid, ascorbic acid, levulinic acid, succinic acid, glutaric acid, glutamic acid, and fumaric acid. Citric acid, tartaric acid, lactic acid, pyrrolidone carboxylic acid, pyrone carboxylic acid, pyrrole carboxylic acid, furan carboxylic acid, viridine carboxylic acid, coumaric acid, thiophene carboxylic acid, nicotinic acid, oxysuccinic acid, dioxysuccinic acid and the like.

  The content of the salt or organic acid in the reaction solution is preferably 10% by mass or more and 90% by mass or less in consideration of the effect according to the present embodiment. Further, the reaction solution does not necessarily have to show no absorption in the visible range. Even if it shows absorption in the visible range, it may show absorption in the visible range as long as it does not substantially affect the image.

(Aqueous medium)
Examples of the aqueous medium used for the reaction liquid include water or a mixed solvent of water and a water-soluble organic solvent. As the water-soluble organic solvent, those having an effect of preventing the reaction solution from drying are particularly preferable. Specifically, the thing similar to the aqueous medium used for a process liquid can be mentioned, for example.

  The above water-soluble organic solvents can be used alone or as a mixture. It is desirable to use deionized water as the water. In addition to the above components, a surfactant, an antifoaming agent, an antiseptic, an antifungal agent, and the like can be added as necessary to obtain a reaction solution having desired physical properties.

(Applying reaction solution)
A reaction liquid is applied on the recording medium to which the treatment liquid is applied. As a method for applying the reaction liquid, an inkjet system using an inkjet device is suitable from the viewpoint of adaptability to various recording medium types (paper types), stability of the applied amount, and control of the applied amount.

(Ink application)
Subsequently, ink is applied on the recording medium to which the reaction liquid has been applied to form an image.

(ink)
The composition of the ink is not particularly limited. However, a high-quality image can be formed by using a pigment ink in which the pigment is dispersed or dissolved in an aqueous medium with an ionic group (preferably an anionic group) and the above reaction liquid. Hereinafter, these pigments will be described in detail.

(Pigment)
Examples of the pigment include carbon black and organic pigments.

(Carbon black)
Examples of the carbon black include carbon black pigments such as furnace black, lamp black, acetylene black, and channel black. For example, the following carbon black pigments can be mentioned, but the invention is not limited to these, and conventionally known carbon black can be used.
Raven 7000, Ray Van 5750, Ray Van 5250, Ray Van 5000, Ray Van 3500, Ray Van 2000, Ray Van 1500, Ray Van 1250, Ray Van 1200, Ray Van 1190ULTRA-II, Ray Van 1170, Ray Van 1255 (above, Columbia)
Black Pearls L, Regal 400R, Legal 330R, Legal 660R, Mogul L, Monarch 700, Monak 800, Monak 880, Monak 900, Monak 1000, Monak 1100, Monak 1300, Monak 1400, Valcan XC-72R (above, manufactured by Cabot Corporation),
Color Black FW1, Color Black FW2, Color Black FW2V, Color Black FW18, Color Black FW200, Color Black S150, Color Black S160, Color Black S170, Printex 35, Printex U, Printex V , Printex 140U, Printex 140V, Special Black 6, Special Black 5, Special Black 4A, Special Black 4 (above, manufactured by Degussa)
No. 25, no. 33, no. 40, no. 47, no. 52, no. 900, no. 2300, MCF-88, MA600, MA7, MA8, MA100 (above, manufactured by Mitsubishi Chemical Corporation) and the like.

  Further, magnetic fine particles such as magnetite and ferrite, titanium black and the like may be used as the black pigment.

(Organic pigment)
Specific examples of organic pigments include, but are not limited to, the following carbon black pigments.
Insoluble azo pigments such as Toluidine Red, Toluidine Maroon, Hansa Yellow, Benzidine Yellow, and Pyrazolone Red.
Soluble azo pigments such as Ritolol Red, Helio Bordeaux, Pigment Scarlet, and Permanent Red 2B.
Derivatives from vat dyes such as alizarin, indanthrone and thioindigo maroon, and phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green.
Quinacridone pigments such as quinacridone red and quinacridone magenta.
Perylene pigments such as perylene red and perylene scarlet.
Isoindolinone pigments such as isoindolinone yellow and isoindolinone orange.
Imidazolone pigments such as benzimidazolone yellow, benzimidazolone orange, and benzimidazolone red;
Pilanthrone pigments such as pyranthrone red and pyranthrone orange.
Thioindigo pigments, condensed azo pigments, thioindigo pigments.
Flavanthrone yellow, acylamide yellow, quinophthalone yellow, nickel azo yellow, copper azomethine yellow, perinone orange, anthrone orange, dianthraquinonyl red, dioxazine violet.

  Further, when the organic pigment is represented by a color index (CI) number, C.I. I. Pigment Yellow 12, 13, 14, 17, 20, 24, 74, 83, 86, 93, 109, 110, 117, 120, 125, 128, 137, 138, 147, 148, 151, 153, 154, 166, 168, C.I. I. Pigment orange 16, 36, 43, 51, 55, 59, 61, C.I. I. Pigment Red 9, 48, 49, 52, 53, 57, 97, 122, 123, 149, 168, 175, 176, 177, 180, 192, 215, 216, 217, 220, 223, 224, 226, 227, 228, 238, 240, C.I. I. Pigment violet 19, 23, 29, 30, 37, 40, 50, C.I. I. Pigment blue 15, 15: 3, 15: 1, 15: 4, 15: 6, 22, 60, 64, C.I. I. Pigment green 7, 36, C.I. I. Pigment Brown 23, 25, 26 and the like can be exemplified. Of course, conventionally known organic pigments can be used in addition to the above.

(Self-dispersing pigment)
As the coloring material, a pigment that can be dispersed in an aqueous medium without a dispersant by bonding an ionic group (anionic group) to the pigment surface, a so-called self-dispersing pigment can also be used. An example of such a pigment is self-dispersing carbon black. Examples of the self-dispersing carbon black include those in which an anionic group is bonded to the surface of the carbon black.

(Anionic carbon black)
Examples of the anionic carbon black include at least one anion selected from —COO (M2), —SO ₃ (M2), —PO ₃ H (M2), and —PO ₃ (M2) _{2 on} the surface of the carbon black. The thing which combined the sex group is mentioned. In the above formula, M2 represents a hydrogen atom, an alkali metal, ammonium or organic ammonium. Among these, carbon black in which —COO (M2) or —SO ₃ (M2) is bonded to the surface of the carbon black and anionicly charged can be particularly preferably used because of its excellent dispersibility in the ink. .

  Among those expressed as “M2”, specific examples of the alkali metal include Li, Na, K, Rb, and Cs. Specific examples of organic ammonium include methyl ammonium, dimethyl ammonium, trimethyl ammonium, ethyl ammonium, diethyl ammonium, triethyl ammonium, methanol ammonium, dimethanol ammonium, and trimethanol ammonium.

  Further, an ink containing self-dispersing carbon black in which M2 is ammonium or organic ammonium can be used particularly suitably because it can further improve the water resistance of the recorded image. The reason for this is considered to be due to the effect of ammonium being decomposed and ammonia being evaporated when ink is applied onto the recording medium.

An example of a method for producing an anionically charged self-dispersing carbon black is a method of oxidizing carbon black with sodium hypochlorite. By this method, the —COONa group can be chemically bonded to the carbon black surface. In addition, the various hydrophilic groups as described above may be directly bonded to the surface of carbon black, or other atomic groups are interposed between the carbon black surface and the hydrophilic group so that the hydrophilic group is carbon black. It may be indirectly bonded to the surface. Here, specific examples of the other atomic groups include, for example, a linear or branched alkylene group having 1 to 12 carbon atoms, a substituted or unsubstituted phenylene group, and a substituted or unsubstituted naphthylene group. It is done. Here, as a substituent of a phenylene group and a naphthylene group, a C1-C6 linear or branched alkyl group is mentioned, for example. Specific examples of combinations of other atomic groups and hydrophilic groups include, for example, —C ₂ H ₄ COO (M2), —Ph—SO ₃ (M2), —Ph—COO (M2), etc. , Ph represents a phenyl group).

  In addition, as a manufacturing method of said self-dispersion type carbon black which used M2 as ammonium, the method of substituting M2 of the self-dispersion type carbon black whose M2 is an alkali metal with ammonium using an ion exchange method is mentioned. Moreover, after adding acid and making it H type, the method etc. which add ammonium hydroxide and make M2 ammonium are mentioned.

  Also, two or more kinds of the above self-dispersing carbon black may be appropriately selected and used as the ink coloring material. Further, the addition amount of the self-dispersing carbon black in the ink is preferably 0.1% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass or less with respect to the total mass of the ink. . By setting this range, the self-dispersing carbon black can maintain a sufficiently dispersed state in the ink. Furthermore, for the purpose of adjusting the color tone of the ink, a dye may be added as a coloring material in addition to the self-dispersing carbon black.

(Colored fine particles / microencapsulated pigment)
In addition to the above-described materials, pigments microencapsulated with polymers or the like, and colored fine particles in which the periphery of resin particles is coated with a color material can also be used. The microcapsules inherently have dispersibility in an aqueous medium, but a dispersant as described above may be further coexisted in the ink in order to improve dispersion stability. In addition, when the colored fine particles are used as a coloring material, it is preferable to use the anionic dispersant described above.

(Dispersant)
When the carbon black or organic pigment is used as the ink pigment, it is preferable to use a dispersant together. As the dispersant, those capable of stably dispersing the pigment in an aqueous medium by the action of an anionic group can be suitably used.

  Specific examples of the dispersant include, for example, a styrene-acrylic acid copolymer, a styrene-acrylic acid-alkyl acrylate copolymer, a styrene-maleic acid copolymer, and a styrene-maleic acid-alkyl acrylate copolymer. Styrene-methacrylic acid copolymer, styrene-methacrylic acid-acrylic acid alkyl ester copolymer, styrene-maleic acid half ester copolymer, vinyl naphthalene-acrylic acid copolymer, vinyl naphthalene-maleic acid copolymer, A styrene-maleic anhydride-maleic acid half ester copolymer or a salt thereof is included. These dispersants preferably have a weight average molecular weight in the range of 1,000 to 30,000, and particularly preferably in the range of 3,000 to 15,000.

(Aqueous medium)
The aqueous medium in which the pigment in the ink is dispersed is not particularly limited, and the same aqueous medium as described above can be used as the aqueous medium used in the treatment liquid. In addition, when color ink is applied to a recording medium by an ink jet method (for example, a bubble jet (registered trademark) method), it is preferable to adjust the ink characteristics so as to have excellent ink jet discharge characteristics as described above. Examples of the ink characteristics include ink viscosity and surface tension.

  Examples of the aqueous medium used for the ink include water or a mixed solvent of water and a water-soluble organic solvent. As the water-soluble organic solvent, those having an effect of preventing the reaction solution from drying are particularly preferable.

  The above water-soluble organic solvents can be used alone or as a mixture. Moreover, it is desirable to use deionized water as water. The content of the water-soluble organic solvent in the ink is not particularly limited, but is preferably in the range of 3% by mass to 50% by mass with respect to the total mass of the ink. The content of water contained in the ink is preferably in the range of 50% by mass to 95% by mass with respect to the total mass of the reaction solution. Further, in addition to the above components, a moisturizing agent may be added to the ink as necessary, and a surfactant, antifoaming agent, preservative, antifungal agent, etc. are added to obtain an ink having a desired physical property value. It may be added.

(Fixing)
As an additional step, the recording medium on which image recording has been performed may be pressed with a roller to increase its surface smoothness. In this case, it is preferable to heat the roller, since the fastness of the image may be improved.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In the following description, “parts” or “%” are based on mass unless otherwise specified.

(Preparation of black pigment dispersion)
The following materials were mixed and charged in a batch type vertical sand mill (manufactured by Imex), filled with 150 parts of 0.3 mm-diameter zirconia beads, and dispersed for 2 hours while cooling with water.
Carbon black (Product name: BLACK PEARLS 880, manufactured by Cabot Corporation, DBP oil absorption 112 cc / 100 g, BET specific surface area 220 m ² / g)
10 parts anionic polymer PA (styrene-butyl acrylate-acrylic acid copolymer, acid value 120, weight average molecular weight 7400, 10% solids aqueous solution, neutralizer: potassium hydroxide) 50 parts pure water 40 copies.

  This dispersion was treated with a centrifugal separator to remove coarse particles, and a black pigment dispersion having a final preparation with a solid content of 15% and an average particle size of 105 nm was obtained.

(Preparation of ink)
The components shown below were mixed, dissolved sufficiently by stirring, and then pressure filtered through a microfilter (manufactured by Fuji Film Co., Ltd.) having a pore size of 1.0 μm to prepare an ink used in this example.
Black pigment dispersion 20 parts glycerin 10 parts acetylenol E100 (manufactured by Kawaken Fine Chemical Co.) 1 part water remaining.

(Reaction solution adjustment)
The components shown below were mixed, dissolved sufficiently by stirring, and then pressure filtered with a microfilter (manufactured by Fuji Film Co., Ltd.) having a pore size of 1.0 μm to prepare a reaction solution used in this example.
Levulinic acid 40 parts Glycerin 5 parts 8N KOH aqueous solution (manufactured by Kishida Chemical Co., Ltd.) 2.4 parts acetylenol E100 (manufactured by Kawaken Fine Chemical Co., Ltd.) 1 part Water remaining.

(Adjustment of processing solution)
The components shown in Table 1 below were mixed and sufficiently stirred to dissolve, and then pressure filtered with a micro filter (manufactured by Fuji Film Co., Ltd.) having a pore size of 1.0 μm to prepare a treatment liquid used in this example.

(* 1) Methanol dispersion of hydrophilic silica particles, solid content: 7%, volume average particle size: 25 nm (made by Sketch)
(* 2) Water dispersion of hydrophilic silica particles, solid content: 10%, volume average particle size: 12 nm (manufactured by Nissan Chemical Industries)
(* 3) Water dispersion of hydrophilic silica particles, solid content: 20%, volume average particle size: 20 nm (manufactured by Nissan Chemical Industries)
(* 4) Fluorosurfactant (manufactured by DuPont).

(Evaluation of uniformity of solid image area)
Using the treatment liquid, reaction liquid, and ink, a printed matter was obtained by the following method.
Using a modified PIXUS Pro 9500 (manufactured by Canon Inc.), the treatment liquid was applied at 25% duty on the two types of recording media shown in Table 2 below, and then the reaction liquid was applied at 25% duty. Thereafter, a solid image of 100% duty of 10 mm × 10 mm was drawn with ink. Note that “100% duty” means that one droplet is ejected onto a 1200 dpi × 1200 dpi grid. Further, the difference in application time between the treatment liquid and the reaction liquid was 0.4 s, and the difference in application time between the reaction liquid and the ink was 1.4 s.

The uniformity of the solid image portion of the obtained printed matter was evaluated using an optical microscope (20 times). The evaluation was performed according to the following criteria.
Uniformity of solid image portion ○: Solidity of solid image portion where almost no unevenness is observed Δ: Uniformity of solid image portion where unevenness is partially observed ×: Overall unevenness is observed.
The results are shown in Table 2.

(* 5) Cast coated paper, basis weight 127.9 g / m ² (Oji Paper Co., Ltd.)
(* 6) Coated paper, basis weight 127.9 g / m ² (Nippon Paper Industries)
As is apparent from the results in Table 2, it can be seen that according to the present invention, it is possible to provide an image recording method capable of obtaining an image with excellent uniformity of the solid image portion.

Claims (2)

Applying a treatment liquid containing silica particles to the recording medium;
Providing the recording medium with a reaction liquid for aggregating or precipitating the coloring material contained in the ink;
And a step of applying an ink containing a coloring material to the recording medium in this order.   The image recording method according to claim 1, wherein the recording medium is cast-coated paper.