JP2008012774A - Inkjet recording material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording material enabling attainment of an image which has a high printing density for both of dye/pigment ink and an excellent mar resistance and has a matte tone, depth and stableness. <P>SOLUTION: The inkjet recording material has at least two ink accepting layers on a substrate and the ink accepting layer (A) being the uppermost layer provided at the most distant position from the substrate mainly contains inorganic particulates of which the average secondary particle diameter is 500 nm or less. The ink accepting layer (B) provided between the uppermost ink accepting layer (A) and the substrate mainly contains a wet silica of which the average secondary particle diameter is 1.5-2.5 μm, and a dry coating amount of the uppermost layer (A) is 0.2-1.5 g/m<SP>2</SP>. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ink jet recording material, and more particularly to an ink jet recording material having a high printing density for both dye and pigment ink, excellent scratch resistance, and a matte and deep calm image.

  As a recording material used in the ink jet recording method, a recording material in which an ink receiving layer is provided on a support such as paper or a plastic resin film is known. The ink receiving layer is roughly classified into two types. One type is an ink receiving layer mainly composed of a water-soluble polymer, and the other type is a porous ink receiving layer mainly composed of an inorganic pigment and a resin binder.

  The former type of ink receiving layer absorbs ink by swelling the water-soluble polymer. The latter type of ink receiving layer absorbs ink in voids formed by inorganic pigments. Due to the difference in ink absorption mechanism, the former type is called a swelling type (or polymer type), and the latter type is called a void type.

  In recent years, a photographic image having an image quality comparable to a silver salt photograph can be printed by an ink jet recording method, and an ink jet recording material having photo-like gloss and texture has been demanded. For such applications, the former polymer type ink-receiving layer is excellent in gloss because it forms a continuous uniform film, but has poor ink absorbability (ink absorption speed; drying speed after printing), while the latter This void type is preferable because of its excellent ink absorbability and high print density. As the latter void type, it has been proposed to use inorganic fine particles such as gas phase method silica or wet method silica pulverized and dispersed to a particle diameter of 500 nm or less as a pigment component of the ink receiving layer. For example, JP-A-3-56552, JP-A-10-119423, JP-A-2000-2111235, and JP-A-2000-309157 disclose examples of using vapor phase silica. JP-A-9-286165, JP-A-10 No. 181190 discloses a use example of pulverized sedimentation silica, and Japanese Patent Application Laid-Open No. 2001-277712 discloses a use example of crushed gel method silica.

  As for the type of ink printed by the ink jet method, conventionally, dye-based ink has been mainly used. The dye molecules in the dye ink are fixed in the ink absorption layer in a substantially molecular state, but are easily affected by oxygen due to the presence in the molecular state, and generally photobleaching is significantly accelerated by the contribution of oxygen. Therefore, there is a problem that light resistance is not sufficient. Therefore, when printing on the above-mentioned void type recording material, the dye ink penetrates and is absorbed in the fine voids in the coating layer, and the dye remains in the voids when the solvent component containing water in the ink volatilizes. Therefore, the problem of light resistance appears more prominently.

  From the viewpoint of the above light resistance, it is known to use a pigment ink having high fastness as a colorant. However, pigment inks tend to be difficult to obtain a sufficient print image density, although ink storability is superior to water-soluble dye inks in which a colorant is present as a single molecule, and ink particles are not acceptable. In order to form a film on the surface without entering the layer, there is a problem in the scratch resistance of the printed image, and a solution has been desired. An ink jet recording material for pigment ink using inorganic fine particles which has improved this problem has also been proposed. For example, Japanese Patent Application Laid-Open No. 2002-274021 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2005-103827 (Patent Document 2) disclose an ink jet recording material excellent in color developability of pigment ink, and Japanese Patent Application Laid-Open No. 2001-96907. JP-A No. 2003-251915 discloses an ink jet recording material having excellent scratch resistance.

  However, the ink-jet recording material known so far is not satisfactory as an ink-jet recording material for both dye and pigment ink, although a certain effect is recognized when printing is performed using pigment ink. . Several reports have been made on recording media that are good for both dye ink and pigment ink. For example, Japanese Patent Application Laid-Open No. 10-119417 (Patent Document 3) discloses a method of providing an outermost layer mainly composed of a water-soluble resin on an ink receiving layer mainly composed of an inorganic filler. Japanese Unexamined Patent Publication No. 2000-094831 (Patent Document 4) discloses a method of providing a porous layer containing silica and a binder on an ink receiving layer using an alumina hydrate having a boehmite structure. In JP-A-2003-276316 (Patent Document 5), a method of providing a glossy expression layer having colloidal silica and a binder on an ink receiving layer using synthetic amorphous silica having an average particle diameter of 4 to 18 μm. It is disclosed. Furthermore, in JP-A-2006-001028 (Patent Document 6), the outermost surface coating layer contains wet-process silica having an average secondary particle diameter of 500 nm or less as a main component, and the outermost surface coating layer A method is disclosed in which an adjacent inner coating layer is provided with an ink receiving layer containing vapor phase silica having an average secondary particle diameter of 700 nm or less.

  On the other hand, as described above, since a photographic image having an image quality comparable to a silver salt photograph can be printed by the ink jet recording method, an ink jet recording material having photo-like gloss and texture has been demanded. In general, a recording material having high glossiness is desired. However, a recording material capable of obtaining a matted tone and a deep and calm image is desired depending on the user's preference and the like. In order to obtain such a recording material, the gloss must be suppressed and the print density must be high.

  JP-A-2005-053136 (Patent Document 7) discloses an inorganic pigment having an average particle diameter of 1 to 10 μm as a recording material that can be used for both dye and pigment inks and can provide a matte and deep and calm image. And a method of providing an ink receiving layer containing alumina or an alumina hydrate as an upper layer. Furthermore, in JP-A-2005-280150 (Patent Document 8), the outermost layer is an ink jet recording material containing a cationic water-soluble substance, a binder, and a pigment, and the pigment contains 5 to 55% by mass of colloidal particles and is porous. Discloses a method of providing an outermost layer containing 45 to 95% by mass of crystalline amorphous silica. However, when printing was performed on the recording material using a dye ink, the color developability was not fully satisfactory even though the absorbency was satisfactory.

On the other hand, in order to obtain desired characteristics, a technique is known in which a plurality of ink receiving layers having different characteristics are coated on a support. For example, as a recording material with low ink absorption and ink bleeding, a specific peak appears in the hole distribution curve of the uppermost layer and the entire ink image receiving layer as described in JP-A No. 58-110287 (Patent Document 9). Recording materials having are known. Japanese Patent Laid-Open No. 2002-248849 (Patent Document 10) discloses an ink receiving layer containing wet-process silica for the purpose of obtaining excellent gloss, film strength, water resistance, ozone resistance, and light resistance. An ink jet recording material provided with a surface layer containing vapor phase silica is described. JP-A-10-315610 (Patent Document 11) is used for the purpose of obtaining excellent gloss, printing density, and ink absorbability, and JP-A-2003-72224 (Patent Document 12) is excellent. Average particle size of inorganic fine particles contained in the upper ink-receiving layer for the purpose of obtaining high glossiness, printing density, ink absorption, transparency between unprinted and printed areas, glossiness, moisture resistance, etc. An ink jet recording sheet is described in which the diameter is smaller than the average particle diameter of the inorganic fine particles contained in the lower ink receiving layer. Further, JP-A-2004-237704 (Patent Document 13) discloses silica fine particles obtained by pulverizing and dispersing a wet process silica having an average aggregated particle diameter of 1.0 to 2.8 μm and a binder, except for the uppermost layer and the uppermost layer. An ink jet recording sheet for use in the ink receiving layer is described. JP-A-2001-277712 (Patent Document 14) discloses pigment fine particles having an average particle diameter of 1 μm or less, such as silica and alumina, as a recording material excellent in printing density, water resistance, surface smoothness and gloss. Is included in one layer of a single layer or a laminated structure. However, since many of these have high surface gloss, they are not satisfactory as ink jet recording materials that can be used in both dye and pigment inks and can provide a matte and deep and calm image.
Japanese Patent Laid-Open No. 2002-274021 JP 2005-103827 A JP 10-119417 A JP 2000-094831 A JP 2003-276316 A JP 2006-001028 A Japanese Patent Laying-Open No. 2005-053136 JP 2005-280150 A JP 58-110287 A JP 2002-248849 A Japanese Patent Laid-Open No. 10-315610 JP 2003-72224 A JP 2004-237704 A JP 2001-277712 A

  An object of the present invention is to provide a matte tone and deep and calm image ink jet recording material having high printing density, excellent color developability and good scratch resistance, for both dye and pigment ink.

The above object of the present invention has been achieved by the following ink jet recording material.
(1) Inorganic fine particles having at least two ink receiving layers on a support, and the uppermost ink receiving layer (A) provided at the position farthest from the support has an average secondary particle diameter of 500 nm or less And the ink receiving layer (B) provided between the uppermost ink receiving layer (A) and the support is made of wet-process silica having an average secondary particle size of 1.5 to 2.5 μm. An ink jet recording material comprising a main component and a dry coating amount of the uppermost ink receiving layer (A) of 0.2 to 1.5 g / m ² .
(2) The ink jet recording material as described in (1) above, wherein the inorganic fine particles having an average secondary particle diameter of 500 nm or less, which is mainly contained in the ink receiving layer (A), are vapor phase silica.
(3) The ink receiving layer (B) contains a compound having two or more primary amino groups in the molecule and a resin binder having a keto group, as described in (1) or (2) above Inkjet recording material.
(4) The inkjet recording material as described in any one of (1) to (3) above, wherein the wet process silica is a gel process silica.

  According to the ink jet recording material of the present invention, it is possible to obtain a calm image having a high printing density with both dye and pigment ink, excellent scratch resistance, matte tone and depth.

Hereinafter, the present invention will be described in detail.
The support used in the present invention is a water-absorbing support such as fine paper, art paper, coated paper, cast coated paper, polyester resin such as polyethylene terephthalate and polyethylene naphthalate, diacetate resin, triacetate resin, nitrocellulose Cellulose ester resin such as cellulose acetate, polyolefin resin, acrylic resin, polycarbonate resin, polyvinyl chloride, polyimide resin, polysulfone, polyphenylene oxide, cellophane, celluloid and other plastic resin films, polyolefin resin coated paper, etc. A so-called non-water-absorbing support or the like which is a support having no or low ink absorbability is used. Among them, a non-water-absorbing support is preferably used, and among the non-water-absorbing supports, a polyolefin resin-coated paper in which at least one surface of a base paper is coated with a polyolefin resin is particularly preferably used. As the pulp constituting the base paper, natural pulp, recycled pulp, synthetic pulp or the like is used alone or in combination of two or more. This base paper may be blended with additives such as sizing agent, paper strength enhancing agent, filler, antistatic agent, fluorescent brightening agent, dye and the like generally used in papermaking. Alternatively, a surface sizing agent, a surface paper strength agent, a fluorescent brightening agent, an antistatic agent, a dye, an anchor agent, or the like may be applied on the surface.

In addition, the thickness of the base paper is not particularly limited, but preferably has a good surface smoothness such as a paper that is compressed by applying a pressure during or after paper making using a calendar or the like, and has a basis weight of 30 to 250 g / m ² is preferred. However, the density of the base paper is 1.10 g / cm ³ or less, preferably 0.6 to 1.05 g / cm ³ for rigidity. If the density is too small, it is difficult to obtain uniform surface smoothness even if resin coating is performed.

  Examples of polyolefin resins include low-density polyethylene, high-density polyethylene, polypropylene, polybutene, olefin homopolymers such as polypentene, or copolymers composed of two or more olefins such as ethylene-propylene copolymer, and mixtures thereof. Those having various densities and melt viscosity indices (melt index) can be used alone or in combination.

  In polyolefin resin, white pigments such as titanium oxide, zinc oxide, talc and calcium carbonate, fatty acid amides such as stearic acid amide and arachidic acid amide, zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, etc. Fatty acid metal salts, antioxidants such as Irganox 1010 and Irganox 1076, blue pigments and dyes such as cobalt blue, ultramarine blue, cecilian blue and phthalocyanine blue, magenta pigments such as cobalt violet, fast violet and manganese purple It is preferable to add various additives such as dyes, fluorescent brighteners and ultraviolet absorbers in appropriate combinations.

  The polyolefin resin-coated paper used in the present invention is produced by a so-called extrusion coating method in which a heated and melted resin is cast on a traveling base paper, and the surface or both sides thereof are coated with the resin. Moreover, it is preferable to subject the base paper to an activation treatment such as corona discharge treatment or flame treatment before coating the resin on the base paper. The surface (front surface) of the polyolefin resin-coated paper on which the ink receiving layer is applied is processed into a glossy surface, a matte surface, or the like according to the application. Although it is not necessary to coat the resin on the back surface, it is preferable to coat the resin from the viewpoint of curling prevention. The back surface is usually a matte surface, and an active treatment such as corona discharge treatment or flame treatment can be applied to the front surface or both the front and back surfaces as necessary. Further, the thickness of the polyolefin resin-coated paper is not particularly limited, but is generally coated on the surface or both sides of the surface to a thickness of 5 to 50 μm on one side.

Next, the ink receiving layer (B) provided between the uppermost ink receiving layer (A) and the support of the present invention will be described.
The ink receiving layer (B) of the present invention contains wet-process silica having an average secondary particle size of 1.5 to 2.5 μm. When the average secondary particle diameter is less than 1.5 μm or exceeds 2.5 μm, the print density decreases. The oil absorption of the wet process silica in the present invention is preferably in the range of 200 to 350 ml / 100 g. The oil absorption is measured based on the description of JIS K-5101. If the oil absorption is less than 200 ml / 100 g or more than 350 ml / 100 g, the scratch resistance is deteriorated.

  Wet process silica is further classified into precipitation process silica and gel process silica according to the production method. Precipitated silica is produced by reacting sodium silicate and sulfuric acid under alkaline conditions, and the silica particles that have grown are agglomerated and settled, and are then commercialized through filtration, water washing, drying, pulverization and classification. The silica secondary particles produced by this method become gently agglomerated particles, and particles that are relatively easy to grind are obtained. The precipitated silica is commercially available, for example, as a nip seal from Tosoh Silica Co., Ltd., as a Toku Seal from Tokuyama Co., Ltd., and as a fine seal. Gel silica produces silicate sol by reacting sodium silicate and sulfuric acid under acidic conditions. The silicate sol gradually polymerizes to form primary particles, and further, a three-dimensional aggregate is formed and gelled. This silica is pulverized and pulverized by a general method such as airflow pulverization. That is, in the gel method, reaction polymerization is carried out on the acidic side, left standing until it becomes a gel, washed with water and dried to obtain gel method silica. For example, it is commercially available in the form of a fine powder from Tosoh Silica Co., Ltd. as a nip gel and from Mizusawa Chemical Co., Ltd. as Mizukasil. In addition, the coarsely pulverized granular material is generally expressed as silica gel, and is used as a desiccant or a chromatography filler. From Toyoda Chemical Co., Ltd., QP type, from Fuji Silysia Chemical Co., Ltd. It is commercially available as Fuji Silica Gel.

  The wet process silica can be further finely pulverized for use. As a pulverization method, a wet dispersion method in which silica dispersed in an aqueous medium is mechanically pulverized can be preferably used. As the wet disperser, a media mill such as a ball mill, a bead mill, and a sand grinder, a pressure disperser such as a high pressure homogenizer, and an ultra high pressure homogenizer, an ultrasonic disperser, and a thin film swirl disperser can be used.

  In the present invention, gel method silica is particularly preferable because it has high absorbability and improves color developability. The average secondary particle size of the wet method silica used in the present invention can be obtained by measuring a diluted dispersion of silica with a laser diffraction / scattering particle size distribution analyzer, for example, LA-920 manufactured by Horiba, Ltd. It can be measured by a commercially available particle size distribution measuring device such as LS230 manufactured by Beckman Coulter.

In the present invention, the ink receiving layer (B) mainly contains wet process silica having an average secondary particle size of 1.5 μm to 2.5 μm based on the total solid content in the ink receiving layer (B). It means that 50 mass% or more of wet process silica is contained. More preferably, it is 60 mass% or more, Most preferably, it is 65 mass% or more, and an upper limit is about 95 mass%. The amount of wet-process silica having an average secondary particle size of 1.5~2.5μm in the present invention preferably contains 8 g / m ² or more, the use further in the range of 10 to 40 g / m ² More preferred.

  In the present invention, the wet process silica used for the ink receiving layer (B) is usually dispersed in an aqueous medium, but a dispersant may be added as necessary. A dispersing agent may be used independently and may use 2 or more types together. A usable dispersing agent is preferably one that adsorbs to the surface of the silica particles and functions to stabilize the dispersion, and examples thereof include a cationic compound.

  As the cationic compound used for the dispersion of the wet process silica, a cationic polymer or a water-soluble metal compound can be used. Examples of the cationic polymer include polyethyleneimine, polydiallylamine, polyallylamine, alkylamine polymer, JP-A-59-20696, JP-A-59-33176, JP-A-59-33177, JP-A-59-155088. JP, 60-11389, JP 60-49990, JP 60-83882, JP 60-109894, JP 62-198493, JP 63-49478, 1 described in JP-A-63-115780, JP-A-63-280681, JP-A-1-40371, JP-A-6-234268, JP-A-7-125411, JP-A-10-193976, etc. A polymer having a tertiary amino group or a quaternary ammonium base is preferably used. In particular, diallylamine derivatives are preferably used as the cationic polymer. In terms of dispersibility and dispersion viscosity, the molecular weight of these cationic polymers is preferably about 2,000 to 100,000, and particularly preferably about 2,000 to 30,000.

  Examples of the water-soluble metal compound include water-soluble polyvalent metal salts, and among them, a compound made of aluminum or a group 4A metal (for example, zirconium or titanium) in the periodic table is preferable. Particularly preferred is a water-soluble aluminum compound. As a water-soluble aluminum compound, for example, as an inorganic salt, aluminum chloride or a hydrate thereof, aluminum sulfate or a hydrate thereof, ammonium alum and the like are known. Furthermore, a basic polyaluminum hydroxide compound which is an inorganic aluminum-containing cationic polymer is known and preferably used.

The basic polyaluminum hydroxide compound has a main component represented by the following general formula 1, 2, or 3, for example, [Al ₆ (OH) ₁₅ ] ³⁺ , [Al ₈ (OH) ₂₀ ] ⁴⁺ , [Al ₁₃ (OH) ₃₄ ] ⁵⁺ , [Al ₂₁ (OH) ₆₀ ] ³⁺ , etc. is there.

[Al ₂ (OH) _n Cl _6-n ] _m General formula 1
[Al (OH) ₃ ] _n AlCl ₃ general formula 2
Al _n (OH) _m Cl _(3n-m) 0 <m <3n General formula 3

  These are water treatment agents from Taki Chemical Co., Ltd. under the name of polyaluminum chloride (PAC), from Asada Chemical Co., Ltd. under the name of polyaluminum hydroxide (Paho), and from Riken Green Co., Ltd. It is marketed under the name of Purachem WT and from other manufacturers for the same purpose, and various grades can be easily obtained.

  As the water-soluble compound containing a Group 4A element of the periodic table used in the present invention, a water-soluble compound containing titanium or zirconium is more preferable. Examples of the water-soluble compound containing titanium include titanium chloride and titanium sulfate. Water-soluble compounds containing zirconium include zirconium acetate, zirconium chloride, zirconium oxychloride, hydroxy zirconium chloride, zirconium nitrate, basic zirconium carbonate, zirconium hydroxide, zirconium lactate, zirconium carbonate / ammonium, zirconium carbonate / potassium, zirconium sulfate. And zirconium fluoride compounds. In the present invention, the term “water-soluble” means that 1% by mass or more dissolves in water at room temperature and normal pressure.

  As the resin binder used in the ink receiving layer (B), various known binders can be used, and a hydrophilic binder is preferably used. When using a hydrophilic binder, it is important that the hydrophilic binder does not swell during initial penetration of the ink to prevent voids. From this viewpoint, a hydrophilic binder having a relatively low swellability around room temperature is preferable. Used. Casein, starch, methylcellulose, polyvinyl alcohol, silyl polyvinyl alcohol and the like are known as binders. Particularly preferred hydrophilic binders in the present invention are fully or partially saponified polyvinyl alcohol or cation-modified polyvinyl alcohol. Among the polyvinyl alcohols, a part having a saponification degree of 80% or more or a completely saponified one is preferable. Those having an average degree of polymerization of 200 to 5000 are preferred. The amount used is 10 to 30% by mass with respect to wet-process silica having an average secondary particle size of 1.5 to 2.5 μm. The ink receiving layer (B) in the present invention preferably uses various crosslinking agents (hardeners). Specific examples of the crosslinking agent are the same as those used for the ink receiving layer (A) described later. Furthermore, as a resin binder used for the ink receiving layer (B), a resin binder having a keto group is particularly preferable from the viewpoint of color developability with a dye ink.

  In the present invention, the ink receiving layer (B) preferably contains a compound having two or more primary amino groups in the molecule together with the resin binder having the keto group.

  Hereinafter, an embodiment containing a compound having two or more primary amino groups in the molecule and a resin binder having a keto group will be described. It is preferable to preliminarily contain a compound having two or more primary amino groups in the molecule together with a binder having a keto group in the coating liquid of the ink receiving layer (B), because the viscosity of the coating liquid may become unstable. There may not be. Therefore, although the following method can be mentioned as preferable embodiment, This invention is not limited to these.

(1) A resin binder having a keto group is contained in the coating liquid of the ink receiving layer (B), and at least one layer adjacent to the ink receiving layer (B) (for example, in the case of a two-layer structure, the uppermost ink receiving layer) (A)) A coating solution containing a compound having two or more primary amino groups in the molecule and coating simultaneously using a slide bead method or the like described later.
(2) As a layer adjacent to the side closer to the support of the ink receiving layer (B) (for example, an intermediate layer, an undercoat layer on the support surface, etc.), a compound having two or more primary amino groups in the molecule is contained. A method of applying an ink receiving layer (B) containing a resin binder having a keto group and an uppermost ink receiving layer (A) after previously coating and drying the layer.

  By using the above method, a compound having two or more primary amino groups in the molecule added to the coating liquid of the layer adjacent to the ink receiving layer (B) diffuses into the ink receiving layer (B). The ink receiving layer (B) can contain a compound having two or more primary amino groups in the molecule and a resin binder having a keto group, and can be stably produced.

  The resin binder having a keto group in the present invention can be synthesized by a method of copolymerizing a monomer having a keto group and another monomer. Specific examples of the monomer having a keto group include acrolein, diacetone acrylamide, diacetone methacrylate, acetoacetoxyethyl methacrylate, 4-vinylacetoacetanilide, acetoacetylallylamide, and the like. Further, a keto group may be introduced by a polymer reaction. For example, an acetoacetyl group can be introduced by a reaction between a hydroxy group and a diketene. Specific examples of the resin binder having a keto group include acetoacetyl-modified polyvinyl alcohol, acetoacetyl-modified cellulose derivatives, acetoacetyl-modified starch, diacetone acrylamide-modified polyvinyl alcohol, and resin binders described in JP-A-10-157283. Can be mentioned. In the present invention, modified polyvinyl alcohol having a keto group is particularly preferable. Examples of the modified polyvinyl alcohol having a keto group include acetoacetyl-modified polyvinyl alcohol and diacetone acrylamide-modified polyvinyl alcohol.

  The acetoacetyl-modified polyvinyl alcohol can be produced by a known method such as a reaction between polyvinyl alcohol and diketene. The degree of acetoacetylation is preferably from 0.1 to 20 mol%, more preferably from 1 to 15 mol%. The saponification degree is preferably 80 mol% or more, more preferably 85 mol% or more. As a polymerization degree, the thing of 500-5000 is preferable, and the thing of 1000-4500 is especially preferable.

  Diacetone acrylamide-modified polyvinyl alcohol can be produced by a known method such as saponification of a diacetone acrylamide-vinyl acetate copolymer. As content of a diacetone acrylamide unit, the range of 0.1-15 mol% is preferable, and also the range of 0.5-10 mol% is preferable. The saponification degree is preferably 85 mol% or more, and the polymerization degree is preferably 500 to 5,000.

  In the present invention, in addition to the resin binder having a keto group, another known resin binder may be used in combination as long as the effect of the resin binder having a keto group is not hindered. For example, cellulose derivatives such as carboxymethyl cellulose and hydroxypropyl cellulose, starch and various modified starches, gelatin and various modified gelatins, chitosan, carrageenan, casein, soy protein, polyvinyl alcohol and various modified polyvinyl alcohols such as cationic modified polyvinyl alcohol, Polyvinyl pyrrolidone, polyacrylamide, etc. can be used together as necessary. Furthermore, various latexes may be used in combination as the binder resin.

  The smaller the total content of these resin binders, the smaller the void volume in the ink receiving layer and the better the ink absorbability.However, if the amount is too small, the ink receiving layer becomes brittle and surface defects such as cracks increase. Therefore, the range of 10 to 40 mass% is preferable with respect to the inorganic fine particles, and 10 to 30 mass% is particularly preferable.

  Next, a compound containing two or more primary amino groups of the present invention in the molecule will be described. The primary amino group of the present invention includes an aliphatic group, an aromatic group, a primary amino group bonded to a carbon atom of a heterocyclic group, and a primary amino group bonded to a nitrogen atom (that is, a terminal amino group of hydrazine). From the viewpoint of the thickening effect after mixing, a hydrazine-type amino group is preferable, and a hydrazide, semicarbazide, or carbohydrazide structure is particularly preferable. Specific examples of the compound having two or more primary amino groups bonded to carbon atoms include ethylenediamine, diethylenetriamine, triethylenetetramine, metaxylenediamine, norbornanediamine, 1,3-bisaminomethylcyclohexane, etc., and hydrazine type Specific examples of the compound having two or more amino groups include hydrazine and its salts, carbohydrazide, succinic acid dihydrazide, adipic acid dihydrazide, citric acid trihydrazide, sebacic acid dihydrazide, and isophthalic acid dihydrazide. 1, 2-di-4-semicarbazide ethane, 1,6-di-4-semicarbazide hexane and other polyisocyanate and hydrazine reaction products, polyacrylic acid hydrazide and other polymer type hydrazides. In particular, succinic acid dihydrazide and adipic acid dihydrazide are preferable in terms of water solubility and reactivity.

  The content of the compound containing two or more primary amino groups in the molecule of the present invention is 0.1 to 50 with respect to the resin binder having a keto group in terms of productivity and characteristics of the obtained ink receiving layer. A range of 1% to 20% by mass is preferred.

  In the ink-receiving layer (B) in the present invention, known cationic polymers, preservatives, surfactants, coloring dyes, colored pigments, ultraviolet absorbers, antioxidants, and pigment dispersions together with the resin binder having the keto group. An agent, an antifoaming agent, a leveling agent, a fluorescent brightening agent, a viscosity stabilizer, a pH adjusting agent and the like can also be added.

Next, the uppermost ink receiving layer (A) will be described.
The inorganic fine particles mainly contained in the uppermost ink receiving layer (A) of the present invention are inorganic fine particles having an average secondary particle diameter of 500 nm or less. “Containing mainly inorganic fine particles” means that the inorganic fine particles are contained in an amount of 50% by mass or more, more preferably 60% by mass or more, based on the total solid content in the ink receiving layer (A). It is about 95% by mass. The average secondary particle diameter can be measured by the same method as the average secondary particle diameter of the wet process silica used for the ink receiving layer (B) described above. Examples of the inorganic fine particles mainly used in the uppermost ink receiving layer (A) of the present invention include various known fine particles such as synthetic amorphous silica, alumina, alumina hydrate, calcium carbonate, and magnesium carbonate. Amorphous silica and alumina hydrate are preferably used. Synthetic amorphous silica includes a gas phase method, a wet method, and others. In the present invention, gas phase method silica is particularly preferable. Vapor phase silica is also called a dry method and is generally made by flame hydrolysis. Specifically, a method of making silicon tetrachloride by burning with hydrogen and oxygen is generally known, but silanes such as methyltrichlorosilane and trichlorosilane can be used alone or silicon tetrachloride instead of silicon tetrachloride. Can be used in a mixed state. Vapor phase silica is commercially available from Nippon Aerosil Co., Ltd. as Aerosil and Tokuyama Co., Ltd. as QS type.

  As the alumina used in the present invention, γ-alumina which is a γ-type crystal of aluminum oxide is preferable, and among them, a δ group crystal is preferable. γ-alumina can make primary particles as small as about 10 nm. Usually, secondary particles of thousands to tens of thousands of nanometers are averaged by ultrasonic, high-pressure homogenizer, counter collision type jet crusher, etc. What grind | pulverized the particle diameter to 500 nm or less, Preferably about 20-300 nm can be used.

The alumina hydrate of the present invention is represented by a constitutive formula of Al ₂ O ₃ .nH ₂ O (n = 1 to 3). The case where n is 1 represents an alumina hydrate having a boehmite structure, and the case where n is greater than 1 and less than 3 represents an alumina hydrate having a pseudo boehmite structure. It can be obtained by a known production method such as hydrolysis of an aluminum alkoxide such as aluminum isopropoxide, neutralization of an aluminum salt with an alkali, or hydrolysis of an aluminate. The average secondary particle diameter of the alumina hydrate used in the present invention is 500 nm or less, preferably 20 to 300 nm. The method for obtaining the average secondary particle size in alumina and alumina hydrate is synonymous with the method for obtaining the average secondary particle size described above.

  The above-mentioned alumina and alumina hydrate used in the present invention are used in the form of a dispersion dispersed by a known dispersant such as acetic acid, lactic acid, formic acid, nitric acid and the like.

The average particle diameter of primary particles of vapor-phase process silica particularly preferably used in the ink receiving layer (A) of the present invention is preferably 5 to 30 nm, more preferably 15 nm or less. More preferably, the primary particles have an average particle diameter of 5 to 15 nm and a specific surface area of 200 m ² / g or more by the BET method. The BET method referred to in the present invention is one of powder surface area measurement methods by vapor phase adsorption, and is a method for determining the total surface area, that is, the specific surface area of a 1 g sample from the adsorption isotherm. Usually, nitrogen gas is often used as the adsorbed gas, and the most frequently used method is to measure the amount of adsorption from the change in pressure or volume of the gas to be adsorbed. The most prominent expression for expressing the isotherm of multimolecular adsorption is the Brunauer, Emmett, and Teller formula, called the BET formula, which is widely used for determining the surface area. The adsorption amount is obtained based on the BET equation, and the surface area is obtained by multiplying the area occupied by one adsorbed molecule on the surface. The average primary particle diameter described here is obtained as the particle diameter of a circle, which is equal to the projected area of each of 100 particles existing within a certain area by electron microscope observation of the dispersed particles.

  For the ink receiving layer (A), vapor-phase method silica and wet method silica are used in the presence of a cationic compound, and the average secondary particle diameter of the silica is 500 nm or less, preferably 10 to 300 nm, more preferably 20 to 200 nm. Dispersed in can be used. As a dispersion method, gas phase method silica and a dispersion medium are premixed by ordinary propeller stirring, turbine type stirring, homomixer type stirring, etc., and then a media mill such as a ball mill, a bead mill, a sand grinder, a high pressure homogenizer, an ultrahigh pressure, etc. It is preferable to perform dispersion using a pressure disperser such as a homogenizer, an ultrasonic disperser, a thin film swirl disperser, or the like. The cationic compound is the same as the cationic compound used for dispersing the wet method silica in the ink receiving layer (B).

  Two or more kinds of inorganic fine particles may be used in combination from the inorganic fine particles described above. For example, combined use of finely divided wet method silica and vapor phase method silica, combined use of finely divided wet method silica and alumina or alumina hydrate, and combined use of vapor phase method silica and alumina or alumina hydrate. It is done.

In the present invention, the amount of inorganic fine particles having an average secondary particle diameter of 500 nm or less used for the uppermost ink-receiving layer (A) is preferably 0.18 to 1.05 g / m ² , and preferably 0.18 to 0.7 g. / M ² is more preferable, and a range of 0.18 to 0.35 g / m ² is particularly preferable. The above range is preferable in terms of color developability and gloss in the dye ink.

  The ink receiving layer (A) of the present invention has a resin binder together with the inorganic fine particles having an average secondary particle diameter of 500 nm or less. A preferred resin binder is polyvinyl alcohol or cation-modified polyvinyl alcohol. Among them, a partially polymerized polyvinyl alcohol having an average degree of polymerization of 200 to 5000 and a saponification degree of 80% or more is preferable. The preferable usage-amount of a resin binder is 5-30 mass% with respect to the inorganic fine particle whose average secondary particle diameter is 500 nm or less.

  Various crosslinkers (hardeners) can be used for the ink receiving layer (A) in the present invention. Specific examples of the crosslinking agent include aldehyde compounds such as formaldehyde and glutaraldehyde, ketone compounds such as diacetyl and chloropentanedione, bis (2-chloroethylurea), 2-hydroxy-4,6-dichloro-1, 3,5-triazine, compounds having reactive olefins as described in US Pat. No. 3,635,718, isocyanates as described in US Pat. No. 3,103,437, US Pat. No. 3,017,280 No. 2,983,611, halogen carboxaldehydes, dioxane derivatives such as dihydroxyoxane, chromium alum, inorganic crosslinking agents such as zirconium sulfate, boric acid, borate, etc. Species or a combination of two or more can be used. The usage-amount is 0.02-50 mass% with respect to polyvinyl alcohol, and 0.5-35 mass% is especially preferable.

  Similarly to the ink receiving layer (B), the ink receiving layer (A) is a cationic polymer, an antiseptic, a surfactant, a coloring dye, a coloring pigment, an ultraviolet absorber, an antioxidant, a pigment dispersant, an anti-foaming agent. Foaming agents, leveling agents, fluorescent whitening agents, viscosity stabilizers, pH adjusting agents and the like can also be added. A compound containing two or more primary amino groups in the molecule can also be added.

In the present invention, the range of the dry coating amount of the uppermost ink-receiving layer (A) is 0.2 to 1.5 g / m ² , more preferably 0.2 to 1.0 g / m ² . A range of 0.2 to 0.5 g / m ² is particularly preferable. When it is 0.2 g / m ² or less, the color development with dyes and pigment inks deteriorates, and when it is 1.5 g / m ² or more, the gloss becomes high.

  The glossiness of the recording material of the present invention, that is, the 75 ° specular glossiness defined by JIS-P-8741 of the surface of the uppermost ink-receiving layer (A) is preferably 20% or less. Usually, in order to keep the glossiness low, for example, the surface of the ink receiving layer as described in JP-A-2001-096907 and JP-A-2005-053136 is molded so that the 75-degree specular gloss is 20% or less. In addition, it is known that an outermost layer having a matting agent and pigment particles having an average particle diameter of 1 μm or more as described in JP-A-2004-001449 is provided on the upper layer of the ink receiving layer. However, with the conventional method described above, a matte tone and deep and calm image cannot be obtained when using any ink of dye or pigment, and sufficient print density when using pigment ink is sufficient. In addition, scratch resistance could not be secured. On the other hand, by adopting the constitution of the ink receiving layer (B) of the present invention and the ink receiving layer (A) which is the uppermost layer, both the dye and the pigment ink have high printing density, excellent color development, and scratch resistance. Thus, an ink jet recording material having a matte tone having a good property and a deep and calm image can be obtained.

  In the present invention, a known coating method can be used as a coating method of each layer constituting the ink receiving layer. For example, there are a slide bead method, a curtain method, an extrusion method, an air knife method, a roll coating method, a rod bar coating method, and the like.

  When the ink receiving layer coating liquid is applied to the support, preferably, corona discharge treatment, flame treatment, ultraviolet irradiation treatment, plasma treatment or the like is performed prior to coating.

  In the present invention, it is preferable to provide an undercoat layer mainly composed of a natural polymer compound or a synthetic resin on the surface of the support on which the ink receiving layer is provided.

  The undercoat layer provided on the support is mainly composed of natural polymer compounds such as gelatin and casein and synthetic resins. Examples of such synthetic resins include acrylic resins, polyester resins, vinylidene chloride, vinyl chloride resins, vinyl acetate resins, polystyrene, polyamide resins, polyurethane resins, and the like. In the above-described embodiment (2), a compound containing two or more primary amino groups in the molecule can also be contained, but in other embodiments, various crosslinking agents (hardeners). Can be used.

  The undercoat layer is provided on the support with a film thickness (dry film thickness) of 0.01 to 5 μm. Preferably it is the range of 0.05-5 micrometers.

  In the present invention, in the method of containing the resin binder having a keto group and the compound having two or more primary amino groups in the molecule, the ink receiving layer (B) is close to the support of the ink receiving layer (B). When an intermediate layer is further provided on the undercoat layer as a layer adjacent to the side, the same binder and surfactant as the above-described undercoat layer can be used for the intermediate layer. Moreover, as thickness, it is provided by the film thickness (dry film thickness) of 0.1-20 micrometers on an undercoat layer, Preferably it is the range of 0.5-10 micrometers.

  Various back coat layers can be coated on the support in the present invention for antistatic properties, transport properties, anticurling properties, and the like. The back coat layer may contain an appropriate combination of inorganic antistatic agent, organic antistatic agent, resin binder, latex, pigment, curing agent, surfactant and the like.

  Examples of the present invention will be described below, but the present invention is not limited to these examples. In the examples and comparative examples, “parts” and “%” indicate parts by mass and mass% unless otherwise specified. In addition, the number of parts shown in the blend is the number of substantial components.

(Production of support)
A 1: 1 mixture of hardwood kraft pulp (LBKP) and softwood sulfite pulp (NBSP) was beaten to 300 ml with Canadian Standard Freeness to prepare a pulp slurry. As a sizing agent, alkylketene dimer is 0.5% to pulp, polyacrylamide is 1.0% to pulp, and cationized starch is 2.0% to pulp. Polyamide epichlorohydrin resin is 0 to pulp. 0.5% was added and diluted with water to make a 1% slurry. This slurry was made with a long paper machine to a basis weight of 170 g / m ² , dried and conditioned to obtain a base paper for the support. A polyethylene resin composition in which 10% anatase-type titanium is uniformly dispersed with respect to a resin of 100% low density polyethylene having a density of 0.918 g / cm ³ is melted at 320 ° C. on the base paper thus produced at 200 m / min. The surface was extrusion-coated using a cooling roll that had been extrusion-coated to a thickness of 35 μm and fine-roughened. On the other side, a blend resin composition of 30 parts by mass of a low density polyethylene resin having a density of 0.918 g / cm ³ is similarly melted at 320 ° C., extrusion coated to a thickness of 30 μm, and roughened. Using a cooling roll, it was extrusion coated to make the back side.

After subjecting the surface of the support to high-frequency corona discharge treatment, an undercoat layer having the following composition was prepared by coating and drying so that gelatin was 50 mg / m ² .
(Undercoat layer)
Lime-processed gelatin: 100 parts, Sulfosuccinic acid-2-ethylhexyl ester salt: 2 parts, Chrome alum: 10 parts

(The uppermost ink receiving layer (A))
4 parts of dimethylallyl ammonium chloride homopolymer (molecular weight 9,000) and 100 parts of gas phase method silica (average primary particle diameter 7 nm) are added to ion-exchanged water, and a sawtooth blade type disperser (blade peripheral speed 20 m / second) is added. This was passed through a pressure homogenizer once under the condition of 40 MPa to obtain a silica dispersion having a solid content concentration of 20% and an average secondary particle size of 150 nm.

  Using 103 parts of the above dispersion, 23 parts of a polyvinyl alcohol solution (solid content concentration 8%, manufactured by Kuraray Co., Ltd .: PVA235, saponification degree 88%, polymerization degree 3500), adipic acid dihydrazide 10 parts, 4% boron 3.5 parts of an acid and 0.3 part of a fluorosurfactant (manufactured by Seimi Chemical Co., Ltd .: Surflon S-131) were mixed with a 3% aqueous ethanol solution to prepare a coating solution for the ink receiving layer (A). . The coating solution concentration at this time was 12%.

(Ink receiving layer (B))
(Dispersion adjustment)
Commercially available wet silica (trade name: NIPGEL AY-200, BET specific surface area 300 m ² / g, pore volume 1.6 ml / g, oil absorption 280 ml / 100 g, gel method silica, manufactured by Tosoh Silica Co., Ltd.) It disperse | distributed continuously with the disperser (The special machine industry Co., Ltd. make, TK Robotics) with ion-exchange water. T.A. K. Robomix was used at 3000 rpm. Thereafter, AGESTAT A50 (Ciba Specialty Chemicals Water Treatment, Inc. USA, polyethylene polyamine / dimethylamine / epichlorohydrin polycondensate, hereinafter referred to as AGA50) was added to 5 parts with respect to 100 parts of silica, and It was made to disperse | distribute at 3000 rpm with said disperser. The solid concentration of silica in the dispersion was 14%. The average secondary particle size of the silica dispersion was measured with a particle size distribution meter (Horiba, LA-920), and the result was 2.3 μm.

(Adjustment of ink receiving layer (B) coating solution)
105 parts of the above dispersion, 0.5 part of acetic acid, 23 parts of an acetoacetyl-modified polyvinyl alcohol solution (solid content concentration 8%, manufactured by Nippon Synthetic Chemical Industry Co., Ltd .: Gohsephimer Z410), a fluorosurfactant ( Seimi Chemical Co., Ltd. product: Surflon S-131 (0.3 parts) was mixed with a 3% aqueous ethanol solution to prepare a coating solution. The coating solution concentration at this time was 12%.

(Production of recording material)
The ink receiving layer (B) coating liquid and the uppermost ink receiving layer (A) coating liquid were applied on the surface of the support on which the undercoat layer had been coated, respectively, with a dry coating amount of 24.7 g / m ² , 0.003. The recording material of Example 1 was produced by simultaneously applying with a slide bead coating device so as to be 3 g / m ² .

100 parts of a polyvinyl alcohol solution (solid concentration 10%, manufactured by Kuraray Co., Ltd .: PVA405, saponification degree 80%, polymerization degree 500) on the surface of the support on which the undercoat layer of Example 1 was applied, adipic acid A coating solution prepared by mixing 70 parts of dihydrazide with a 3% aqueous ethanol solution was applied with a slide bead coating device so as to have a dry coating amount of 1.0 g / m ² and dried. Thereafter, the ink receiving layer (B) coating solution of Example 1 and the uppermost ink receiving layer (A) coating solution of Example 1 to which adipic acid dihydrazide was not added were each dried at a coating amount of 24.7 g / m. ² and 0.3 g / m ² were simultaneously applied by a slide bead coating apparatus to produce a recording material of Example 2.

A recording material of Example 3 was produced in the same manner as in Example 1 except that the coating liquid for the uppermost ink-receiving layer (A) in Example 1 was changed to a dry coating amount of 1.0 g / m ² .

A recording material of Example 4 was produced in the same manner as in Example 1 except that the coating liquid for the uppermost ink-receiving layer (A) in Example 1 was changed to a dry coating amount of 1.5 g / m ² .

  Except for changing the acetoacetyl-modified polyvinyl alcohol of the ink receiving layer (B) coating liquid in Example 1 to diacetone acrylamide-modified polyvinyl alcohol (diacetone acrylamide modification degree 5 mol%, saponification degree 98 mol%, polymerization degree 1700). A recording material of Example 5 was produced in the same manner as Example 1.

  A recording material of Example 6 was prepared in the same manner as in Example 1 except that the adipic acid dihydrazide in the coating liquid for the uppermost ink-receiving layer (A) in Example 1 was changed to succinic acid dihydrazide.

Mizkasil P-803 (manufactured by Mizusawa Chemical Co., Ltd., BET specific surface area 180 m ² / g, pore volume 0.6 ml / g) instead of AY-200 of the ink receiving layer (B) dispersion in Example 1 The recording material of Example 7 was produced in the same manner as in Example 1 except that the oil absorption was 210 ml / 100 g and the precipitated silica was used. The average secondary particle diameter of this silica dispersion was measured with a particle size distribution meter (Horiba, LA-920), and the result was 2.4 μm.

  Example 1 except that adipic acid dihydrazide in the uppermost ink-receiving layer (A) coating solution in Example 1 was not added, but 2.3 parts of adipic acid dihydrazide was added in-line to the ink-receiving layer (B) immediately before coating. In the same manner as described above, the recording material of Example 8 was produced.

Instead of vapor phase method silica used in the uppermost ink-receiving layer (A) of Example 1, wet method silica (manufactured by Tosoh Silica Co., Ltd., NIPGEL AZ-200, BET specific surface area of 300 m ² / g, Example 9 was carried out in the same manner as in Example 1 except that a coating liquid for the ink receiving layer (A) was prepared as follows using a pore volume of 2.0 ml / g, an oil absorption of 330 ml / 100 g, and silica gel method). A recording material was prepared. The average secondary particle diameter of this silica dispersion was measured with a particle size distribution meter (Horiba, LA-920), and the result was 2.4 μm.

(Primary dispersion process of dispersion of gel method silica)
Industrial water having an electric conductivity of 150 mS / cm is set to a flow rate of 5.0 L / min by using a cartridge pure water production apparatus (manufactured by Organo Corporation, model G-5), and the electric conductivity is 9.0 μS / min. cm water was prepared. Next, 7.0 kg of the water was weighed, and 3.0 kg of gel method silica (NIPGEL AZ-200, manufactured by Tosoh Silica Co., Ltd.) was added, and a disperser (Special Machine Industries Co., Ltd., Hibiss) was added. Disperse mix 3D-10 type) was used for dispersion for 60 minutes at a disperse peripheral speed of 21.0 m / sec and a planetary rotation speed of 30 rpm to obtain a 30% gel silica dispersion.

(Secondary dispersion step of dispersion of gel method silica)
The gel method silica dispersion obtained in the primary dispersion step was subjected to a bead filling rate of 70% by volume (using 0.3 mmΦ zirconia beads) with a bead mill (Shinmaru Enterprises Co., Dynomill), a disk peripheral speed of 12.5 m / second, Two-pass processing was performed under the condition of a pump flow rate of 300 ml / min. The average secondary particle diameter of this dispersion was measured with a particle size distribution meter (LA-920, manufactured by Horiba, Ltd.), and the result was 200 nm.

(Adjustment of uppermost ink receiving layer (A) coating solution)
Using 103 parts of the above dispersion, 23 parts of a polyvinyl alcohol solution (solid content concentration 8%, manufactured by Kuraray Co., Ltd .: PVA235, saponification degree 88%, polymerization degree 3500), adipic acid dihydrazide 19 parts, 4% boron 3.5 parts of an acid and 0.3 part of a fluorosurfactant (manufactured by Seimi Chemical Co., Ltd .: Surflon S-131) were mixed with a 3% aqueous ethanol solution to prepare a coating solution for the ink receiving layer (A). . The coating solution concentration at this time was 12%.

  Instead of the wet method silica used in the ink-receiving layer (B) of Example 1, wet method silica (manufactured by Tosoh Silica Co., Ltd., NIPGEL AZ-200, gel method silica) was used as follows. A recording material of Example 10 was produced in the same manner as in Example 1 except that the coating solution for the receiving layer (B) was produced.

(Primary dispersion process of dispersion of gel method silica)
Using industrial water with an electrical conductivity of 150 mS / cm and a cartridge pure water production apparatus (Gorgan-5, Model G-5), the flow rate is set to 5.0 L / min and the electrical conductivity is 9.0 μS / cm. Water was prepared. Next, 7.0 kg of the water was weighed, and 3.0 kg of gel method silica (NIPGEL AZ-200, manufactured by Tosoh Silica Co., Ltd.) was added, and a disperser (manufactured by Tokushu Kika Kogyo Co., Ltd., Hibis Dispermix 3D-10) The dispersion was carried out for 60 minutes at a dispersion speed of 21.0 m / sec and a planetary rotation speed of 30 rpm to obtain a 30% gel silica dispersion.

(Secondary dispersion step of dispersion of gel method silica)
The gel method silica dispersion obtained in the primary dispersion step was subjected to a beads filling rate of 50% by volume (using 0.3 mmΦ zirconia beads) with a bead mill (Shinmaru Enterprises Co., Ltd., Dynomill), a disk peripheral speed of 12.5 m / second, One-pass processing was performed under the condition of a pump flow rate of 300 ml / min. The average secondary particle size was measured by a particle size distribution meter (LA-920, manufactured by Horiba, Ltd.), and the result was 1.8 μm.

(Adjustment of ink receiving layer (B) coating solution)
105 parts of the above dispersion, 0.5 part of acetic acid, 23 parts of an acetoacetyl-modified polyvinyl alcohol solution (solid content concentration 8%, manufactured by Nippon Synthetic Chemical Industry Co., Ltd .: Gohsephimer Z410), a fluorosurfactant ( Seimi Chemical Co., Ltd. product: Surflon S-131 (0.3 parts) was mixed with a 3% aqueous ethanol solution to prepare a coating solution. The coating solution concentration at this time was 12%.

  The adipic acid dihydrazide in the uppermost ink-receiving layer (A) of Example 1 was deleted, and the acetoacetyl-modified polyvinyl alcohol in the ink-receiving layer (B) was changed to unmodified polyvinyl alcohol (manufactured by Kuraray Co., Ltd .: PVA235, degree of saponification). 88%, degree of polymerization 3500) The recording material of Example 11 was prepared in the same manner as in Example 1 except that 23 parts of boric acid was added.

(Comparative Example 1)
Instead of the wet method silica used in the ink-receiving layer (B) of Example 1, wet method silica (manufactured by Tosoh Silica Co., Ltd., NIPGEL AZ-200, gel method silica) was used as follows. A recording paper of Comparative Example 1 was prepared in the same manner as in Example 1 except that the coating solution for the receiving layer (B) was prepared.

(Primary dispersion process of dispersion of gel method silica)
Using industrial water with an electrical conductivity of 150 mS / cm and a cartridge pure water production apparatus (Gorgan-5, Model G-5), the flow rate is set to 5.0 L / min and the electrical conductivity is 9.0 μS / cm. Water was prepared. Next, 7.0 kg of the water was weighed, and 3.0 kg of gel method silica (manufactured by Tosoh Silica Co., Ltd., NIPGEL AZ-200) was added, and a disperser (made by Tokushu Kika Kogyo Co., Ltd., Hibis Dispermix 3D-10 type) ) Was used for dispersion for 60 minutes at a disperser peripheral speed of 21.0 m / sec and a planetary rotation speed of 30 rpm to obtain a 30% gel silica dispersion.

(Secondary dispersion step of dispersion of gel method silica)
The gel method silica dispersion obtained in the primary dispersion step was subjected to a beads filling rate of 60% by volume (using 0.3 mmΦ zirconia beads) with a bead mill (Shinmaru Enterprises Co., Ltd., Dynomill), a disk peripheral speed of 12.5 m / second, One-pass processing was performed under the condition of a pump flow rate of 300 ml / min. The average secondary particle diameter was measured with a particle size distribution meter (LA-920, manufactured by Horiba, Ltd.), and the result was 1.4 μm.

(Adjustment of ink receiving layer (B) coating solution)
105 parts of the above dispersion, 0.5 part of acetic acid, 23 parts of an acetoacetyl-modified polyvinyl alcohol solution (solid content concentration 8%, manufactured by Nippon Synthetic Chemical Industry Co., Ltd .: Gohsephimer Z410), a fluorosurfactant ( Seimi Chemical Co., Ltd. product: Surflon S-131 (0.3 parts) was mixed with a 3% aqueous ethanol solution to prepare a coating solution. The coating solution concentration at this time was 12%.

(Comparative Example 2)
Instead of AY-200 of the ink receiving layer (B) dispersion in Example 1, NIPGEL CY-200 (manufactured by Tosoh Silica Co., Ltd., BET specific surface area 800 m ² / g, pore volume 1.1 ml / g) The recording material of Comparative Example 2 was prepared in the same manner as in Example 1 except that the oil absorption amount was 185 ml / 100 g and the silica gel method was used. The average secondary particle diameter was measured with a particle size distribution meter (Horiba, LA-920), and the result was 2.7 μm.

(Comparative Example 3)
A recording material of Comparative Example 3 was prepared in the same manner except that the one-pass treatment was performed under the same conditions in the secondary dispersion step of the gel silica dispersion of the ink receiving layer (A) of Example 10. The average secondary particle diameter was measured with a particle size distribution meter (LA-920, manufactured by Horiba, Ltd.), and the result was 750 nm.

(Comparative Example 4)
A recording material of Comparative Example 4 was produced in the same manner as in Example 1 except that the coating liquid for the uppermost ink-receiving layer (A) in Example 1 was changed to a dry coating amount of 0.1 g / m ² .

(Comparative Example 5)
A recording material of Comparative Example 5 was produced in the same manner as in Example 1 except that the coating liquid for the uppermost ink-receiving layer (A) in Example 1 was changed to a dry coating amount of 2.0 g / m ² .

(Comparative Example 6)
A recording material of Comparative Example 6 was produced in the same manner as in Example 1 except that the uppermost ink-receiving layer (A) of Example 1 was not applied.

The following items were evaluated for the obtained recording materials. The results are shown in Table 1.
《Glossiness》
Using a variable angle altimeter (VGS-1001DP) manufactured by Nippon Denshoku Industries Co., Ltd., the 75 ° gloss was measured and evaluated according to the following criteria.
○: A mat. (20.0 or less)
Δ: Slightly glossy but sufficiently matte (20.0-30.0)
X: Glossy and matte texture cannot be obtained. (30.0 or more)

<< Image evaluation 1 >>
A color person image is printed with an ink jet printer (Seiko Epson Corporation, PM-G800; using dye ink), and 100 people are asked visually whether a matte and deep and calm image is obtained. Evaluation was made according to the following criteria. Δ or more satisfies a matte tone and deep calm image.
◯: A calm image with a matte tone and high print density and depth is obtained.
Δ: Slightly inferior in the depth of the image, but has a sufficiently matte texture.
X: Glossy and matte texture cannot be obtained, or the print density is low and the image depth is inferior.

<< Image evaluation 2 >>
Print a monochrome landscape image with an inkjet printer (Seiko-Epson Corporation, PX-5500; using water-based pigment ink) and ask 100 people whether a matte tone and deep calm image is obtained. The following criteria were used for visual evaluation.
◯: A calm image with a matte tone and high print density and depth is obtained.
Δ: Slightly inferior in the depth of the image, but has a sufficiently matte texture.
X: Glossy and matte texture cannot be obtained, or the print density is low and the image depth is inferior.

<< Image evaluation 3 >>
A person image of color is printed with an inkjet printer (Seiko Epson Corporation, PX-5500; using water-based pigment ink), and 100 people are visually informed whether a matte tone and deep, calm image is obtained. The following criteria were evaluated.
◯: A calm image with a matte tone and high print density and depth is obtained.
Δ: Slightly inferior in the depth of the image, but has a sufficiently matte texture.
X: Glossy and matte texture cannot be obtained, or the print density is low and the image depth is inferior.

<Print density>
After black solid printing was performed on an inkjet printer (Seiko Epson Corporation, PX-5500; using aqueous pigment ink), the optical density (OD value) was measured using an optical densitometer (manufactured by Kimoto Co., Ltd., Gretag Macbeth AG SpectroEye). No. 16228). The higher the value, the higher the print density and the better.

《Scratch resistance》
Using an inkjet printer for pigment ink (PX-G900 manufactured by Seiko Epson Corporation), solid printing was continuously performed with a maximum ink discharge amount of Blue, and the image portion through which the giza roll passed was visually evaluated.
○: No peeling of pigment ink.
Δ: Slight peeling of pigment ink.
X: There is peeling of the pigment ink.

From the above results, it can be seen that in the present invention, both dye and pigment inks have high printing density, excellent scratch resistance, and a matte and deep calm image. Further, when the inorganic fine particles mainly contained in the uppermost ink receiving layer (A) are gas phase method silica, and when the wet method silica of the ink receiving layer (B) is gel method silica, the effect is further improved. It turns out to be high. On the other hand, the recording materials of Comparative Examples 1 and 2 contained the wet method silica outside the range of the average secondary particle diameter of 1.5 to 2.5 μm in the ink receiving layer (B). Image evaluation was slightly low. Moreover, since the recording material of Comparative Example 3 contained inorganic fine particles having an average secondary particle size exceeding 500 nm in the ink receiving layer (A), the print density and image evaluation were slightly lower than those of the Examples. In the recording materials of Comparative Examples 4 and 5, since the dry coating amount of the uppermost layer was out of the range of 0.2 to 1.5 g / m ² , there was a tendency that image evaluation with a dye and gloss were deteriorated. . In addition, the recording material of Comparative Example 6 did not have the uppermost ink-receiving layer (A), so that the printing density was low, the coloring with the dye ink was poor, and the scratch resistance was inferior.

Claims (4)

The uppermost ink receiving layer (A), which has at least two ink receiving layers on the support and is provided at the position farthest from the support, is mainly composed of inorganic fine particles having an average secondary particle diameter of 500 nm or less. And the ink receiving layer (B) provided between the uppermost ink receiving layer (A) and the support mainly contains wet-process silica having an average secondary particle size of 1.5 to 2.5 μm. An ink jet recording material, wherein the dry coating amount of the uppermost ink receiving layer (A) is 0.2 to 1.5 g / m ² .   2. The ink jet recording material according to claim 1, wherein the inorganic fine particles having an average secondary particle diameter of 500 nm or less mainly contained in the ink receiving layer (A) are vapor phase method silica.   3. The ink jet recording material according to claim 1, wherein the ink receiving layer (B) contains a compound having two or more primary amino groups in the molecule and a resin binder having a keto group.   The inkjet recording material according to claim 1, wherein the wet process silica is a gel process silica.