JP2008155414A - Inkjet recording material and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording material, which can keep the favorable preservability of a recorded image (concretely can suppress the development of yellowing and keep a favorable ozone resistance) under the condition that bronzing is suppressed and, in addition, can keep a favorable surface condition of an ink accepting layer. <P>SOLUTION: In the inkjet recording material having the ink accepting layer on a support, the ink accepting layer is formed by applying a coating liquid B including a substantially colorless compound having at least ten atoms with a conjugated π electron in one molecule on a coating layer, which has been formed at least with a coating liquid A including fine particles and a water-soluble resin, afterwards the resultant of which has shown falling rate drying. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an inkjet recording material and a method for producing the same.

In recent years, with the rapid development of the information technology industry, various information processing systems have been developed, and recording methods and recording apparatuses suitable for the information processing systems have been developed and put into practical use.
Among these recording methods, the inkjet recording method is capable of recording on a variety of recording materials, has advantages such as being relatively inexpensive and compact in hardware (device), and excellent in quietness. It has also been widely used for so-called home use.

In addition, with the recent increase in resolution of inkjet printers, it has become possible to obtain so-called photographic-like high-quality recorded matter. With the progress of such hardware (devices), inkjet recording media have also become available. Various developments have been made.
The characteristics required for this recording sheet for ink jet recording are generally (1) fast drying (high ink absorption speed), and (2) ink dot diameter is appropriate and uniform. (No blurring), (3) good graininess, (4) high dot roundness, (5) high color density, (6) high chroma (dullness) (7) The water resistance, light resistance, and ozone resistance of the print portion are good, (8) the whiteness of the recording sheet is high, and (9) the storage stability of the recording sheet is good ( Does not cause yellowing coloring even after long-term storage, does not blur images after long-term storage (good aging blur), and (10) resists deformation and has good dimensional stability (small curl) (11) Good hard running performance, etc. That.
Furthermore, in the use of photo glossy paper used for the purpose of obtaining so-called photo-like high-quality recorded matter, in addition to the above properties, gloss, surface smoothness, photographic paper-like texture similar to silver salt photography, etc. Is also required.

  In recent years, an ink jet recording medium having a porous structure in an ink receiving layer has been developed and put into practical use for the purpose of improving the various properties described above. Such an ink jet recording medium has a porous structure, so that it has excellent ink receptivity (fast drying property) and high gloss.

For example, Patent Document 1 and Patent Document 2 propose an ink jet recording medium that includes fine inorganic pigment particles and a water-soluble resin and has an ink receiving layer having a high porosity on a support. .
These recording media, particularly ink jet recording media provided with an ink receiving layer having a porous structure using silica as inorganic pigment fine particles, have excellent ink absorptivity and can form high resolution images. It has high ink receiving performance and can exhibit high gloss.

  On the other hand, when a recording image having a high optical density is formed, a dye crystal precipitates on the surface of the recording material as it dries, and the so-called bronze phenomenon occurs in which the recording image reflects light and emits a metallic luster. Are known. This phenomenon tends to occur easily by reducing the water solubility of the dye in order to improve water resistance, light resistance and gas resistance, or by introducing a hydrogen bonding group into the dye structure. Since the light is reflected and scattered by the occurrence of the bronze phenomenon, not only the optical density of the recorded image is lowered, but also the hue of the recorded image is greatly different from the desired one, and the transparency is lost. Suppression of the phenomenon is one of the important performance requirements for inkjet ink.

  As a method for suppressing the bronze phenomenon, a method for controlling size (for example, see Patent Documents 3 to 6), a method for adding a specific heterocyclic compound (for example, see Patent Document 7), and a specific amine compound are added. A method for adding a specific salt (for example, see Patent Document 9) and the like have been known so far. However, even though the addition of these additives can suppress the occurrence of the bronze phenomenon, the effect is not sufficient, so that the amount of the additive increases and storage stability causes problems such as storage stability. Various performances and quality of recorded images may be deteriorated.

  As described above, various effects can be obtained by using the additive, but it is difficult to use the conventional additive while maintaining various performances. For example, when the image receiving paper is designed so as to enhance the association of the dye and improve the weather resistance of the recorded image, an additive that loosens the association of the dye may be added to suppress the occurrence of the bronze phenomenon. Even if the bronze phenomenon is improved, the storage stability of the recorded image is greatly impaired. Thus, it is found that it is difficult to select the type and amount of the additive particularly when it is necessary to consider the association state of the dye. Further, when an ionic additive is used, the influence of the counter ion must be taken into consideration. Therefore, it has been desired to introduce a molecular design of an additive based on a new idea that has not been heretofore and an essential method for suppressing bronzing.

  As a technique for suppressing the bronze phenomenon and maintaining good storability of the recorded image, a coating layer containing fine particles is formed, and before the coating layer exhibits reduced-rate drying, conjugated π electrons in one molecule. A technique is known in which an ink receiving layer is formed by applying a coating solution containing a substantially colorless compound having 10 or more atoms having s (for example, see Patent Document 10).

JP 10-119423 A Japanese Patent Laid-Open No. 10-217601 JP-A-6-245401 JP-A-6-317088 JP-A-7-75186 JP-A-11-238987 JP 2001-88430 A JP 2000-53765 A JP 2000-309156 A JP 2005-289036 A

  However, before the coating layer containing fine particles exhibits reduced-rate drying, an ink receiving layer is coated by applying a coating solution containing a substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule. When the surface is formed, the surface state of the ink receiving layer may deteriorate.

  The present invention has been made in view of the above, and can maintain the preservability of a recorded image while suppressing the bronze phenomenon (specifically, it suppresses the occurrence of yellowing and has good ozone resistance). In addition, an object of the present invention is to provide an ink jet recording material and a method for producing the same that can maintain a good surface shape of the ink receiving layer, and to achieve the object.

As a result of intensive studies, the present inventors have suppressed the bronzing phenomenon by specifying a means for forming an ink receiving layer containing a substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule. However, the present inventors have found that the surface state of the ink receiving layer can be maintained well, and completed the present invention.
That is, specific means for achieving the above-described problem are as follows.

<1> An ink jet recording material having an ink receiving layer on a support, wherein the ink receiving layer is formed by forming a coating layer using at least a coating liquid A containing fine particles and a water-soluble resin. The coating layer is formed by coating a coating solution B containing a substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule after the coating layer exhibits reduced drying. This is an ink jet recording material.

<2> The inkjet recording material according to <1>, wherein the coating liquid B further contains colloidal silica.
<3> The coating liquid B containing a substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule does not contain a cationic compound <1> or <2 The ink-jet recording material described in the>.

<4> The substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule has at least two aromatic ring groups (including aromatic heterocyclic groups). <1>-<3> It is an inkjet recording material as described in any one.
<5> The substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule is a compound having no fluorescence, and the wavelength of the absorption peak on the longest wave side (λmax) is 350 nm or less, In addition, the ink jet recording material according to any one of <1> to <4>, wherein the molar extinction coefficient at any wavelength in the visible spectral region of 400 to 700 nm is a compound having a molecular weight of 10,000 or less.

<6> Any one of <1> to <5>, wherein the substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule has a solubilizing group. It is an inkjet recording material of description.

<7> A method for producing an ink jet recording material having an ink receiving layer on a support, wherein the ink receiving layer is formed on the support using at least a coating liquid A containing fine particles and a water-soluble resin. And after the formed coating layer exhibits reduced-rate drying, a coating liquid B containing a substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule is formed on the coating layer. An ink jet recording material manufacturing method, wherein the ink jet recording material is formed by applying to an ink jet recording material.

  According to the present invention, it is possible to keep the storage stability of recorded images while suppressing the bronze phenomenon (specifically, it is possible to suppress the occurrence of yellowing and maintain good ozone resistance). Furthermore, it is possible to provide an ink jet recording material capable of maintaining a good surface shape of the ink receiving layer and a method for producing the same.

Hereinafter, the present invention will be described in detail.
≪Inkjet recording material≫
The ink jet recording material of the present invention is an ink jet recording material having an ink receiving layer on a support, and the ink receiving layer forms a coating layer using at least a coating liquid A containing fine particles and a water-soluble resin. After the formed coating layer (hereinafter sometimes referred to as “coating layer in the present invention”) exhibits reduced rate drying, it is substantially colorless having 10 or more atoms having conjugated π electrons in one molecule. The coating liquid B containing the above compound is coated on the coating layer in the present invention.
Hereinafter, the substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule will be described first, and then the ink receiving layer and the support will be described.

<Substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule>
The coating liquid B in the present invention contains a substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule (hereinafter also referred to as “specific compound in the present invention” or “specific compound”). .
When the number of π electrons constituting a conjugated π electron system increases and the π electron system spreads, it often has absorption in the visible region. The specific compound in the present invention is preferably substantially colorless from the viewpoint of color reproduction of an image. The term “substantially colorless” in the present specification includes a state in which the image is slightly colored within a range that does not affect the image.
The specific compound in the present invention may be a fluorescent compound, but is preferably a compound having no fluorescence, more preferably λmax of the absorption peak on the longest wave side is 350 nm or less, more preferably 320 nm or less, and A compound having a molar extinction coefficient of 10,000 or less at an arbitrary wavelength in a visible light spectral region, that is, a spectral region of 400 to 700 nm.
The specific compound in the present invention has 10 or more atoms having conjugated π electrons in one molecule. The upper limit of the number of atoms having conjugated π electrons is not particularly limited, but is preferably 80 or less, more preferably 50 or less, and particularly preferably 30 or less. Further, ten or more conjugated π electrons contained in the specific compound may form one large conjugated system, but may form two or more conjugated systems.
In particular, the specific compound in the present invention is preferably a compound having two or more aromatic ring groups in one molecule. The aromatic ring group in this specification is an aromatic ring group in a broad sense, and forms one aromatic ring group by aromatic hydrocarbon ring group, aromatic heterocyclic group containing a hetero atom, or condensed. Any of the above groups may be used. Examples of the aromatic ring group include a benzene ring group, a naphthalene ring group, an anthracene ring group, a pyridine ring group, a pyrimidine ring group, a pyrazine ring group, and a triazine ring group.

The specific compound in the present invention preferably has a solubilizing group, and more preferably has at least two solubilizing groups. Useful solubilizing groups include, but are not limited to, sulfo groups, carboxyl groups, hydroxy groups, phosphono groups, carbonamido groups, sulfonamido groups, quaternary ammonium salts and other groups apparent to those skilled in the art. . Of these, a sulfo group and a carboxyl group are preferable, and a sulfo group is most preferable.
Although the maximum number of solubilizing groups in a molecule is limited only by the number of available substituent positions, for practical purposes, there may be 10 identical or different solubilizing groups in the molecule. Is enough. There are no limitations on the counter cation of these solubilizing groups, and examples include alkali metal ions, ammonium ions, and organic cations (such as tetramethylammonium, guanidinium, and pyridinium cations), among which alkali metal ions and ammonium ions. In particular, lithium ion, sodium ion and ammonium ion are preferable, and lithium ion and ammonium ion are most preferable.
Specific compounds include JP-A 63-55544, JP-A 3-146947, 3-149543, JP-A 2001-201831, 2002-139822, 2002-196460, Examples thereof include compounds described in JP-A Nos. 2002-244257, 2002-244259, 2002-296743, 2002-296744, and Japanese Patent Application No. 2002-17728.

  Especially, as a specific compound in this invention, the compound represented by the following general formula 1 is used preferably.

In General Formula 1, A, L, and B each independently represent an aromatic group (an aryl group and an aromatic heterocyclic group), but at least two are s-triazine rings. X and Y each independently represent a divalent linking group. n represents 0 or 1. The aromatic group may be a single ring or a condensed ring. The divalent linking group is an alkylene group, an alkenylene _{group, -CO -, - SO m -} (m is 0,1,2), - NR- (R is a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group And -O-, and a divalent group obtained by combining these linking groups. However, the compound represented by the general formula 1 contains at least one ionic hydrophilic group selected from a sulfo group, a carboxyl group, a phenolic hydroxyl group, and a phosphono group as a solubilizing group. These ionic hydrophilic groups may be in the form of a salt, and there are no restrictions on the counter cation, and examples include alkali metal ions, ammonium ions, and organic cations (cations such as tetramethylammonium, guanidinium, and pyridinium). Among them, alkali metal ions and ammonium ions are preferable, lithium ions, sodium ions, potassium ions, and ammonium ions are particularly preferable, and lithium ions, sodium ions, and ammonium ions are most preferable.

  Further, the compound represented by the general formula 1 may have a substituent other than the ionic hydrophilic group, and as specific substituents, an alkyl group, an aryl group, an aralkyl group, a heterocyclic group, an alkoxy group, Aryloxy group, hydroxyl group, amino group (including anilino group and heterocyclic amino group), acyl group, acylamino group, ureido group, halogen atom, sulfamoyl group, carbamoyl group, sulfonamide group, sulfonyl group, sulfenyl group, sulfinyl Group etc. can be mentioned, These may have a substituent further. Among the compounds represented by the general formula 1, those having n = 1 are preferable. Further, those containing 2 to 4 ionic hydrophilic groups are preferred.

  It is not clear from what kind of mechanism the specific compound in the present invention suppresses bronze, but stronger π-electrons than those that aggregate (associate) by π-electron interaction between dye molecules. It acts as a deagglomerating agent that eliminates agglomeration by exerting this interaction, and as a result, it is considered that the bronze phenomenon is improved. The deaggregating agent must be flat and the π-electron system greatly spread in order to enter between the aggregating dyes or to develop a strong π-electron interaction with the dyes on the surface of the dye aggregate. is important. It is also important that the deflocculating agent has sufficient solubility so that the deflocculating agent itself or a complex formed by the dye and the deflocculating agent does not precipitate. The number of π electrons required varies depending on the size of the ink-jet dye used, but the dye used for ink-jet is a plane that is greatly expanded as represented by direct dyes to improve fixability. Since it has a structure, it is presumed that the deaggregating agent needs to be a colorless compound having a spread of more than 10 conjugated π-electron systems in one molecule.

  Preferred examples of the specific compound in the present invention include the aforementioned JP-A Nos. 2002-139822, 2002-196460, 2002-244257, 2002-244259, 2002-296743, and 2002-296744. And the compounds described in Japanese Patent Application No. 2002-17728 and the publications or specifications thereof. Among the specific compounds in the present invention, representative compounds (deaggregating agents) are shown below (Exemplary Compounds P-1 to P-31).

  In the present invention, the number of atoms having a conjugated π electron in a specific compound refers to the number of atoms sharing a π electron group of a conjugated bond structure that can be taken by any conjugated system. Accordingly, the number of atoms having conjugated π electrons matches the number of conjugated π electrons. That is, in the exemplary compounds of P-1 to P-31, if the number of atoms having conjugated π electrons is given as an example, the numbers shown in Table 1 are obtained.

The content of the specific compound in the present invention is preferably 0.01 to 20% by mass, and more preferably 0.1 to 10% by mass with respect to the total solid mass of the ink receiving layer. Moreover, the specific compound in this invention may be used individually, respectively and may be used in combination of 2 or more type.
A preferred compound of the present invention can be easily synthesized with reference to the aforementioned JP-A No. 2002-139822.
In the present specification, the total solid content mass of the ink receiving layer refers to the total mass of components other than water.

<Ink receiving layer>
When forming the ink receiving layer in the present invention, first, the coating layer is formed using at least the coating liquid A containing fine particles and a water-soluble resin. The coating layer may be formed using only the coating solution A, or may be formed using another coating solution A ′ together with the coating solution A.
That is, as an aspect for forming the coating layer, each component for forming an ink receiving layer such as fine particles, water-soluble resin, crosslinking agent, and mordant in the coating liquid A (however, excluding the specific compound in the present invention) In addition to the embodiment in which the coating layer is formed by coating only the coating liquid A, the above-mentioned components (fine particles, dispersant, water-soluble resin, cross-linking agent, mordant, etc.) are added to the coating liquid A and the coating liquid. A mode in which the coating layer is formed by coating the coating liquid A and the coating liquid A ′ is also included.
The “distributed and contained” may be distributed in any manner as long as the coating liquid A contains fine particles and a water-soluble resin. For example, the coating liquid A may contain fine particles, a dispersant, A mode in which a resin and a crosslinking agent are contained and a mordant and a crosslinking agent are contained in the coating liquid A ′ can be mentioned.

  As a method for forming the coating layer in the present invention by using the coating solution A and the coating solution A ′ in combination, the coating solution A is applied on a support, and (1) the coating solution A is applied simultaneously ( 2) The coating liquid A ′ (hereinafter referred to as “basic solution”) may be in the course of drying the coating liquid A coated on the support and before any reduction drying. .) To form a coating layer (Wet-On-Wet method << WOW method >>) is preferably used.

  As described above, the ink receiving layer of the present invention is formed using the coating liquid A (or using the coating liquid A and the coating liquid A ′), and then the formed coating layer is reduced. After showing dryness, the coating liquid B containing the specific compound in the present invention is applied and formed. By forming the ink receiving layer in this manner, a good surface shape can be obtained.

In the present invention, “after the coating layer exhibits reduced rate drying” means “constant rate drying” phenomenon in which the content of the solvent (dispersion medium) in the formed coating layer decreases in proportion to time. Means the time after switching to the phenomenon of reduced rate drying.
The time indicating “constant rate drying” is usually several minutes immediately after application. Specifically, it is described, for example, in the Chemical Engineering Handbook (pages 707 to 712, published by Maruzen Co., Ltd., October 25, 1980).
In the present invention, the time change of the film surface temperature of the formed coating layer is measured, and the time when the film surface temperature starts to rise can be regarded as the time when the constant rate drying is switched to the decrease rate drying.
The time until the coating liquid B is applied after the coating layer shows reduced-rate drying is preferably immediately after 1 hour, more preferably immediately after 30 minutes from the viewpoint of productivity and the like.

(Component of coating liquid A)
The coating liquid A in the present invention contains fine particles and a water-soluble resin as essential components. The coating liquid A in the present invention may further contain other components such as a dispersant, a crosslinking agent, a mordant, and a surfactant as long as the effects of the present invention are not hindered. Details of each component will be described later.

(Component of coating liquid A ′)
In the present invention, the coating liquid A ′ used as necessary can contain components such as a mordant and a crosslinking agent. Details of each component will be described later.

(Component of coating liquid B)
The coating liquid B in the present invention contains at least one of the aforementioned specific compounds as an essential component.
The coating liquid B may contain components such as a surfactant, colloidal silica, and a water-soluble resin in addition to the above-described specific compound that is an essential component within a range that does not interfere with the effects of the present invention.
In particular, when the coating liquid B contains colloidal silica, the glossiness of the ink receiving layer surface can be further improved. In general, the bronze phenomenon tends to deteriorate in a system in which colloidal silica is contained in the outermost surface of the ink receiving layer. It is possible to achieve both the suppression of the brightness and the improvement of the glossiness.

Here, the preferable aspect in the case of making colloidal silica contain in the coating liquid B is demonstrated below.
The colloidal silica is preferably anionic or nonionic from the viewpoint of compatibility with the specific compound. An anionic property is particularly preferable. The ^{content, 0.01g / m 2 ~5g / m} 2 is preferred. 0.05 g / m ² to ² g / m ² is particularly preferable.

A preferred embodiment in the case of containing the water-soluble resin in the coating liquid B is the same as the preferred embodiment described in the section “(Water-soluble resin)” described later.
When the coating liquid B contains colloidal silica and a water-soluble resin, the mass content ratio [PB ratio (x: y)] of the colloidal silica (x) and the water-soluble resin (y) in the coating liquid B is as follows: 10: 1 to 50: 1 are preferred. If the [PB ratio (x: y)] in the coating liquid B is within the above range, the film density and the film strength can be kept higher.

  About the preferable aspect in case surfactant is made to contain in coating liquid B, it is as the preferable aspect described in description of the below-mentioned surfactant.

In the present invention, from the viewpoint of further improving the surface shape of the ink receiving layer and more effectively preventing the thickening of the coating liquid B, the coating liquid B preferably does not contain a cationic compound.
The cationic compound here refers to, for example, a mordant described later, a divalent or higher metal atom described later, and a compound having two or more divalent or higher metal atoms described later.

Hereinafter, each component which comprises coating liquid A, coating liquid A ', and coating liquid B is demonstrated in detail.
(Fine particles)
In the present invention, at least the coating liquid A (and, if necessary, the coating liquid A ′ and / or the coating liquid B) contains at least one kind of fine particles.
The fine particles form a porous structure when the ink receiving layer is formed, and have a role of improving the ink absorption performance.
In particular, when the solid content in the ink receiving layer of the fine particles (that is, the coating liquid A, if necessary, the coating liquid A ′ and / or the coating liquid B) exceeds 50% by mass, more preferably exceeds 60% by mass. Further, it is possible to form a better porous structure, and an ink jet recording material having sufficient ink absorbability can be obtained, which is preferable. Here, the solid content in the ink receiving layer of fine particles is a content calculated based on components other than water in the composition constituting the ink receiving layer.
As the fine particles of the present invention, both organic fine particles and inorganic fine particles can be used, but it is preferable to contain inorganic fine particles from the viewpoint of ink absorbability and image stability.

As the organic fine particles, for example, polymer fine particles obtained by emulsion polymerization, microemulsion polymerization, soap-free polymerization, seed polymerization, dispersion polymerization, suspension polymerization and the like are preferable, and polyethylene, polypropylene, polystyrene, polyacrylate, polyamide, silicon resin are preferable. , Phenol resin, natural polymer powder, latex or emulsion polymer fine particles.
The average particle size of the organic fine particles is preferably 10 μm or less, and more preferably 0.2 to 5 μm.

Examples of the inorganic fine particles include silica fine particles, colloidal silica, titanium dioxide, barium sulfate, calcium silicate, zeolite, kaolinite, halloysite, mica, talc, calcium carbonate, magnesium carbonate, calcium sulfate, pseudoboehmite, zinc oxide, water. Examples thereof include zinc oxide, alumina, aluminum silicate, calcium silicate, magnesium silicate, zirconium oxide, zirconium hydroxide, cerium oxide, lanthanum oxide, and yttrium oxide. Among these, silica fine particles, colloidal silica, alumina fine particles, or pseudoboehmite are preferable from the viewpoint of forming a good porous structure. The fine particles may be used as primary particles or in a state where secondary particles are formed. The average primary particle size of these fine particles is preferably 2 μm or less, and more preferably 200 nm or less.
Further, silica fine particles having an average primary particle size of 30 nm or less, colloidal silica having an average primary particle size of 30 nm or less, alumina fine particles having an average primary particle size of 20 nm or less, or pseudoboehmite having an average pore radius of 2 to 15 nm is more preferable. In particular, silica fine particles, alumina fine particles, and pseudoboehmite are preferable.

  Silica fine particles are generally roughly classified into wet method particles and dry method (gas phase method) particles according to the production method. In the above wet method, a method is mainly used in which activated silica is produced by acid decomposition of a silicate, and this is appropriately polymerized and agglomerated and precipitated to obtain hydrous silica. On the other hand, the gas phase method is a method by high-temperature gas phase hydrolysis of silicon halide (flame hydrolysis method), a method in which silica sand and coke are heated and reduced by an arc in an electric furnace and oxidized with air. The method of obtaining anhydrous silica by the (arc method) is the mainstream, and “gas phase method silica” means anhydrous silica fine particles obtained by the gas phase method. As the silica fine particles used in the present invention, gas phase method silica fine particles are particularly preferable.

Vapor phase silica is different from hydrous silica in terms of the density of silanol groups on the surface, the presence or absence of vacancies, and the like. The reason for this is not clear, but in the case of hydrous silica, the density of silanol groups on the fine particle surface is high at 5 to 8 / nm ² , and the silica fine particles tend to aggregate (aggregate) easily. In the case of the method silica, the density of silanol groups on the surface of the fine particles is 2 to 3 / nm ² , so that it is sparse soft agglomeration (flocculate), resulting in a structure with a high porosity. Is done.

  The above-mentioned vapor phase silica has a particularly large specific surface area, so the ink absorption and retention efficiency is high, and the refractive index is low. Therefore, if the dispersion is made to an appropriate particle size, transparency can be imparted to the receiving layer. It is characterized by high color density and good color development. The transparency of the receiving layer is not only for applications that require transparency, such as OHP, but also in terms of obtaining high color density and good color development gloss even when applied to recording media such as photo glossy paper. is important.

  The average primary particle diameter of the vapor phase silica is preferably 30 nm or less, more preferably 20 nm or less, particularly preferably 10 nm or less, and most preferably 3 to 10 nm. Since the vapor phase silica is easily adhered to each other by hydrogen bonding with a silanol group, a structure having a large porosity can be formed when the average primary particle diameter is 30 nm or less, and ink absorption characteristics are effectively improved. Can be improved.

  Silica fine particles may be used in combination with the other fine particles described above. When the other fine particles and the vapor phase silica are used in combination, the content of the vapor phase silica in all the fine particles is preferably 30% by mass or more, and more preferably 50% by mass or more.

As the inorganic fine particles of the present invention, alumina fine particles, alumina hydrate, a mixture or a composite thereof are also preferable. Of these, alumina hydrate is preferable because it absorbs and fixes ink well, and pseudoboehmite (Al ₂ O ₃ .nH ₂ O) is particularly preferable. Alumina hydrates can be used in various forms, but it is preferable to use sol boehmite as a raw material because a smooth layer can be easily obtained.

About the pore structure of pseudo boehmite, the average pore radius is preferably 1 to 30 nm, and more preferably 2 to 15 nm. The pore volume is preferably 0.3 to 2.0 ml / g, more preferably 0.5 to 1.5 ml / g. Here, the pore radius and pore volume are measured by a nitrogen adsorption / desorption method, and can be measured by, for example, a gas adsorption / desorption analyzer (for example, trade name “Omni Soap 369” manufactured by Coulter). .
Among alumina fine particles, vapor-phase method alumina fine particles are preferable because of their large specific surface area. The average primary particle size of the vapor phase alumina is preferably 30 nm or less, and more preferably 20 nm or less.

  When the above-mentioned fine particles are used for an ink jet recording material, for example, JP-A-10-81064, JP-A-10-119423, JP-A-10-157277, JP-A-10-217601, JP-A-11-348409, JP-A-2001-138621. No. 2000-43401 No. 2000-2111235 No. 2000-309157 No. 2001-96897 No. 2001-138627 No. 11-91242 No. 8-2087 No. 8-2090 No. 8-2091, 8-2093, 8-174992, 11-192777, JP-A-2001-301314, and the like can also be preferably used.

(Water-soluble resin)
In the present invention, at least the coating liquid A (and further, the coating liquid A ′ and / or the coating liquid B if necessary) contains at least one water-soluble resin.
Examples of the water-soluble resin include polyvinyl alcohol resins that are resins having a hydroxy group as a hydrophilic structural unit [polyvinyl alcohol (PVA), acetoacetyl-modified polyvinyl alcohol, cation-modified polyvinyl alcohol, anion-modified polyvinyl alcohol, silanol-modified. Polyvinyl alcohol, polyvinyl acetal, etc.], cellulose resins [methyl cellulose (MC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose, etc.] , Chitins, chitosans, starch, resins with ether linkages [polyethylene oxide (PEO), Propylene oxide (PPO), polyethylene glycol (PEG), poly ether (PVE)], and resins having carbamoyl groups [polyacrylamide (PAAM), polyvinyl pyrrolidone (PVP), polyacrylic acid hydrazide, etc.] and the like.
Moreover, the polyacrylic acid salt which has a carboxyl group as a dissociable group, maleic acid resin, alginate, gelatins, etc. can be mentioned.

Among these, the water-soluble resin used in the present invention is at least one selected from polyvinyl alcohol resins, cellulose resins, resins having an ether bond, resins having a carbamoyl group, resins having a carboxyl group, and gelatins. In particular, polyvinyl alcohol (PVA) resin is preferable.
Examples of the polyvinyl alcohol include Japanese Patent Publication No. 4-52786, Japanese Patent Publication No. 5-67432, Japanese Patent Publication No. 7-29479, Japanese Patent No. 2537827, Japanese Patent Publication No. 7-57553, Japanese Patent No. 2502998, and Japanese Patent No. 3053231. JP-A-63-176173, JP-A-2604367, JP-A-7-276787, JP-A-9-207425, JP-A-11-58941, JP-A-2000-135858, JP-A-2001-205924, JP 2001-287444, JP 62-278080, JP 9-39373, JP 2750433, JP 2000-158801, JP 2001-213045, JP 2001-328345, JP 8 -324105, JP-A-11-348417, JP-A58-18168 JP, 10-259213, JP 2001-72711, JP 2002-103805, JP 2000-63427, JP 2002-308928, JP 2001-205919, JP 2002-264489. And the like described in the above.
Examples of water-soluble resins other than polyvinyl alcohol resins include compounds described in JP-A-11-165461, [0011] to [0012], JP-A-2001-205919, and JP-A-2002-264489. The described compounds are also included.

  These water-soluble resins may be used alone or in combination of two or more. In the present invention, the content of the water-soluble resin is preferably 9 to 40% by mass, and more preferably 12 to 33% by mass with respect to the total solid content of the ink receiving layer.

The water-soluble resin and the fine particles, which mainly constitute the ink receiving layer in the invention, may be a single material or a mixed system of a plurality of materials.
From the viewpoint of maintaining transparency, the type of water-soluble resin to be combined with fine particles, particularly silica fine particles, is important. When the gas phase method silica is used, the water-soluble resin is preferably a polyvinyl alcohol resin, more preferably a polyvinyl alcohol resin having a saponification degree of 70 to 100%, and a saponification degree of 80 to 99.5. % Of polyvinyl alcohol resin is particularly preferred.

The polyvinyl alcohol-based resin has a hydroxyl group in its structural unit, and since this hydroxyl group and the surface silanol group of the silica fine particle form a hydrogen bond, a three-dimensional network having a secondary particle of the silica fine particle as a network chain unit. It becomes easy to form a structure. By forming this three-dimensional network structure, it is considered that a porous ink receiving layer having a high porosity and sufficient strength is formed.
In ink jet recording, the porous ink receiving layer obtained as described above can absorb ink rapidly by a capillary phenomenon, and can form dots with good roundness without ink bleeding.

  In addition, the polyvinyl alcohol resin may be used in combination with the other water-soluble resin. When the other water-soluble resin and the polyvinyl alcohol resin are used in combination, the content of the polyvinyl alcohol resin in the total water-soluble resin is preferably 50% by mass or more, and more preferably 70% by mass or more.

(Content ratio of fine particles to water-soluble resin)
The mass content ratio [PB ratio (x: y)] of the fine particles (x) and the water-soluble resin (y) has a great influence on the film structure and film strength of the ink receiving layer. That is, as the mass content ratio [PB ratio] increases, the porosity, pore volume, and surface area (per unit mass) increase, but the density and strength tend to decrease.

  As the mass content ratio [PB ratio (x: y)] in the coating liquid A (and coating liquid A ′ if necessary) in the present invention, a decrease in film strength caused by the PB ratio being too large, From the viewpoint of preventing cracking at the time of drying and preventing the ink absorbability from being lowered by decreasing the porosity because the voids are easily blocked by the PB ratio being too small. 5: 1 to 10: 1 are preferred.

  Since stress may be applied to the recording medium when passing through the transport system of the ink jet printer, the ink receiving layer needs to have sufficient film strength. Further, when cutting into a sheet shape, the ink receiving layer needs to have sufficient film strength in order to prevent cracking or peeling of the ink receiving layer. In consideration of these cases, the mass ratio (x: y) is more preferably 5: 1 or less, while it is more preferably 2: 1 or more from the viewpoint of ensuring high-speed ink absorbency in an inkjet printer. preferable.

For example, a coating solution in which vapor-phase method silica fine particles having an average primary particle diameter of 20 nm or less and a water-soluble resin are completely dispersed in an aqueous solution at a mass ratio (x: y) of 2: 1 to 5: 1 is provided on the support. When the coating layer is dried, a three-dimensional network structure in which the secondary particles of silica fine particles are network chains is formed, the average pore diameter is 30 nm or less, the porosity is 50 to 80%, the pore ratio A translucent porous film having a volume of 0.5 ml / g or more and a specific surface area of 100 m ² / g or more can be easily formed.

(Crosslinking agent)
The coating liquid A in the present invention (when the coating layer in the present invention is formed using the coating liquid A and the coating liquid A ′, the coating liquid A and / or the coating liquid A ′) It is preferable that a crosslinking agent capable of crosslinking the conductive resin is included.
The ink receiving layer in the invention is preferably a porous layer in which the fine particles and the water-soluble resin are used in combination, and further cured by a cross-linking reaction between the cross-linking agent and the water-soluble resin.

Boron compounds are preferred for the crosslinking of the water-soluble resin, particularly polyvinyl alcohol. Examples of the boron compound include borax, boric acid, borate (eg, _{orthoborate, InBO 3, ScBO 3, YBO} 3, LaBO 3, Mg 3 (BO 3) 2, Co 3 (BO 3) 2, two Borate (eg, Mg ₂ B ₂ O ₅ , Co ₂ B ₂ O ₅ ), metaborate (eg, LiBO ₂ , Ca (BO ₂ ) ₂ , NaBO ₂ , KBO ₂ ), tetraborate (eg, Na _{2 B 4 O 7 · 10H 2} O), can be mentioned five borate _{(e.g., KB 5 O 8 · 4H 2} O, Ca 2 B 6 O 11 · 7H 2 O, CsB 5 O 5) or the like. Among them, Of these, borax, boric acid and borates are preferable, and boric acid is particularly preferable because a crosslinking reaction can be promptly caused.

The following compounds other than the boron compound can also be used as a crosslinking agent for the water-soluble resin.
For example, aldehyde compounds such as formaldehyde, glyoxal, and glutaraldehyde; ketone compounds such as diacetyl and cyclopentanedione; bis (2-chloroethylurea) -2-hydroxy-4,6-dichloro-1,3,5- Active halogen compounds such as triazine and 2,4-dichloro-6-S-triazine sodium salt; divinylsulfonic acid, 1,3-vinylsulfonyl-2-propanol, N, N′-ethylenebis (vinylsulfonylacetamide) ), Active vinyl compounds such as 1,3,5-triacryloyl-hexahydro-S-triazine; N-methylol compounds such as dimethylolurea and methyloldimethylhydantoin; melamine resins (for example, methylolmelamine, alkylated methylolmelamine) ;Epoxy resin;

Isocyanate compounds such as 1,6-hexamethylene diisocyanate; aziridine compounds described in US Pat. Nos. 3,017,280 and 2,983611; carboximide compounds described in US Pat. No. 3,100,704; glycerol triglycidyl Epoxy compounds such as ether; Ethyleneimino compounds such as 1,6-hexamethylene-N, N′-bisethyleneurea; Halogenated carboxaldehyde compounds such as mucochloric acid and mucophenoxycyclolic acid; 2,3-dihydroxy Dioxane-based compounds such as dioxane; titanium-containing aluminum sulfate, chromium alum, potassium alum, metal-containing compounds such as zirconyl acetate, chromium acetate, polyamine compounds such as tetraethylenepentamine, hydrazide compounds such as adipic acid dihydrazide, A low molecule or polymer containing two or more oxazoline groups can be used.
Said crosslinking agent may be used individually by 1 type, and may be used in combination of 2 or more type.

When the coating layer in the present invention is formed using only the coating solution A, the crosslinking agent can be contained in the coating solution A together with the fine particles and the water-soluble resin.
When the coating layer in the present invention is formed using the coating liquid A and the coating liquid A ′, the crosslinking agent may be contained in the coating liquid A ′ without being included in the coating liquid A, or the coating liquid A. And coating solution A ′.

When the coating layer is formed using the coating liquid A and the coating liquid A ′, the crosslinking and curing is performed by adding a crosslinking agent to the coating liquid A and / or the coating liquid A ′ containing fine particles, a water-soluble resin, and the like. (1) Simultaneously with the application of the coating liquid A, or (2) During the drying of the coated coating liquid A and before the coating liquid A exhibits decremental drying, the coating liquid A It is preferable to carry out by giving '.
The coating solution A ′ has a pH of preferably 7.1 or higher, more preferably 7.5 or higher, and particularly preferably 8 or higher.
The application of the cross-linking agent is preferably performed as follows when a boron compound is taken as an example. That is, when the coating layer in the present invention is a layer obtained by crosslinking and curing the coating solution A containing fine particles, polyvinyl alcohol and a water-soluble resin, the crosslinking and curing is performed simultaneously with (1) when the coating solution A is applied ( 2) Applying a coating solution A ′ having a pH of 7.1 or more to the coating layer when the applied coating solution A is being dried and before the coating solution A exhibits reduced-rate drying. Is done. The boron compound as a cross-linking agent may be contained in either the coating liquid A or the coating liquid A ′, or may be contained in both the coating liquid A and the coating liquid A ′.

  1-50 mass% is preferable with respect to water-soluble resin, and, as for the usage-amount of a crosslinking agent, 5-40 mass% is more preferable.

(mordant)
In the present invention, in order to improve the water resistance and aging resistance of the formed image, the coating solution A (when the coating layer in the present invention is formed using the coating solution A and the coating solution A ′) is used. For example, the coating liquid A and / or the coating liquid A ′) may contain an inorganic mordant and / or an organic mordant.
Cationic polymer as the organic mordant (Cationic mordant is preferred, and the presence of the mordant in the ink receiving layer stabilizes the color material by interacting with the liquid ink having the anionic dye as the color material. Water resistance and aging resistance can be improved, and a plurality of organic mordants and inorganic mordants may be used in combination.

  A method of adding a mordant to the coating liquid A containing fine particles and a water-soluble resin, or a method of adding a mordant to the coating liquid A ′ and applying it when there is a concern of aggregation between the fine particles can be used.

As the cationic mordant, a polymer mordant having a primary to tertiary amino group or a quaternary ammonium base as a cationic group is preferably used, but a cationic non-polymer mordant may also be used. it can.
Examples of the polymer mordant include a homopolymer of a monomer having a primary to tertiary amino group and a salt thereof, or a quaternary ammonium base (mordant monomer), and the mordant monomer and other monomers (hereinafter, What is obtained as a copolymer or condensation polymer with "non-mordant monomer") is preferred. These polymer mordants can be used in any form of water-soluble polymer or water-dispersible latex particles.

  Examples of the monomer (mordant monomer) include trimethyl-p-vinylbenzylammonium chloride, trimethyl-m-vinylbenzylammonium chloride, triethyl-p-vinylbenzylammonium chloride, triethyl-m-vinylbenzylammonium chloride, N , N-dimethyl-N-ethyl-Np-vinylbenzylammonium chloride, N, N-diethyl-N-methyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-Nn-propyl-N -P-vinylbenzylammonium chloride, N, N-dimethyl-Nn-octyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N-benzyl-Np-vinylbenzylammonium chloride, N, N-die Ru-N-benzyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N- (4-methyl) benzyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N-phenyl-N -P-vinylbenzylammonium chloride;

Trimethyl-p-vinylbenzylammonium bromide, trimethyl-m-vinylbenzylammonium bromide, trimethyl-p-vinylbenzylammonium sulfonate, trimethyl-m-vinylbenzylammonium sulfonate, trimethyl-p-vinylbenzylammonium acetate, trimethyl-m-vinyl Benzylammonium acetate, N, N, N-triethyl-N-2- (4-vinylphenyl) ethylammonium chloride, N, N, N-triethyl-N-2- (3-vinylphenyl) ethylammonium chloride, N, N-diethyl-N-methyl-N-2- (4-vinylphenyl) ethylammonium chloride, N, N-diethyl-N-methyl-N-2- (4-vinylphenyl) ethylammonium chloride Tate;

N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-diethylaminopropyl (meth) acrylate, N, N- Methyl chloride, ethyl chloride, methyl bromide of dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-diethylaminopropyl (meth) acrylamide , Quaternized products of ethyl bromide, methyl iodide or ethyl iodide, or sulfonates, alkyl sulfonates, acetates or alkyl carboxylates substituted with their anions.

  Specifically, for example, monomethyl diallyl ammonium chloride, trimethyl-2- (methacryloyloxy) ethylammonium chloride, triethyl-2- (methacryloyloxy) ethylammonium chloride, trimethyl-2- (acryloyloxy) ethylammonium chloride, triethyl- 2- (acryloyloxy) ethylammonium chloride, trimethyl-3- (methacryloyloxy) propylammonium chloride, triethyl-3- (methacryloyloxy) propylammonium chloride, trimethyl-2- (methacryloylamino) ethylammonium chloride, triethyl-2- (Methacryloylamino) ethylammonium chloride, trimethyl-2- (acryloylamino) ethyl Ammonium chloride, triethyl-2- (acryloylamino) ethylammonium chloride, trimethyl-3- (methacryloylamino) propylammonium chloride, triethyl-3- (methacryloylamino) propylammonium chloride, trimethyl-3- (acryloylamino) propylammonium chloride Triethyl-3- (acryloylamino) propylammonium chloride;

N, N-dimethyl-N-ethyl-2- (methacryloyloxy) ethylammonium chloride, N, N-diethyl-N-methyl-2- (methacryloyloxy) ethylammonium chloride, N, N-dimethyl-N-ethyl- 3- (acryloylamino) propylammonium chloride, trimethyl-2- (methacryloyloxy) ethylammonium bromide, trimethyl-3- (acryloylamino) propylammonium bromide, trimethyl-2- (methacryloyloxy) ethylammonium sulfonate, trimethyl-3- And (acryloylamino) propylammonium acetate.
In addition, examples of copolymerizable monomers include N-vinylimidazole and N-vinyl-2-methylimidazole.

In addition, allylamine, diallylamine, its derivatives, salts and the like can be used. Examples of such compounds include allylamine, allylamine hydrochloride, allylamine acetate, allylamine sulfate, diallylamine, diallylamine hydrochloride, diallylamine acetate, diallylamine sulfate, diallylmethylamine and salts thereof (for example, Hydrochloride, acetate, sulfate, etc.), diallylethylamine and salts thereof (for example, hydrochloride, acetate, sulfate, etc.), diallyldimethylammonium salt (chloride, acetic acid as counter anions of the salt) Ion sulfate ions, etc.). In addition, since these allylamines and diallylamine derivatives are inferior in polymerizability in the amine form, they are generally polymerized in the form of a salt and desalted as required.
In addition, a unit such as N-vinylacetamide, N-vinylformamide or the like, which is converted into a vinylamine unit by hydrolysis after polymerization, and a salt thereof can also be used.

The non-mordant monomer does not contain a basic or cationic moiety such as a primary to tertiary amino group and a salt thereof, or a quaternary ammonium base, and does not show an interaction with a dye in an inkjet ink. Or the monomer which interaction is substantially small is said.
Examples of the non-mordant monomer include (meth) acrylic acid alkyl ester; (meth) acrylic acid cycloalkyl ester such as cyclohexyl (meth) acrylate; (meth) acrylic acid aryl ester such as phenyl (meth) acrylate; Aralkyl esters such as (meth) benzyl acrylate; Aromatic vinyls such as styrene, vinyl toluene and α-methyl styrene; Vinyl esters such as vinyl acetate, vinyl propionate and vinyl versatate; Allyl esters such as allyl acetate Halogen-containing monomers such as vinylidene chloride and vinyl chloride; vinyl cyanide such as (meth) acrylonitrile; olefins such as ethylene and propylene; and the like.

The (meth) acrylic acid alkyl ester is preferably a (meth) acrylic acid alkyl ester having 1 to 18 carbon atoms in the alkyl moiety, such as methyl (meth) acrylate, ethyl (meth) acrylate, (meth) Propyl acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, Examples include 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, and the like.
Of these, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, and hydroxyethyl methacrylate are preferable.
The non-mordant monomers can also be used singly or in combination of two or more.

Further, as the polymer mordant, polydiallyldimethylammonium chloride, a copolymer of diallyldimethylammonium chloride and another monomer (mordant monomer, non-mordant monomer), a copolymer of diallyldimethylammonium chloride and SO ₂ , polydiallyl Cyclic amine resins such as methylamine hydrochloride and polydiallyl hydrochloride and derivatives thereof (including copolymers); polydiethylmethacryloyloxyethylamine, polytrimethylmethacryloyloxyethylammonium chloride, polydimethylbenzylmethacryloyloxyethylammonium chloride, Secondary amino, tertiary amino or quaternary ammonium salt substituted amides represented by polydimethylhydroxyethylacryloyloxyethylammonium chloride, etc. Kill (meth) acrylate polymers and copolymers with other monomers; polyamine resins such as polyethyleneimine and derivatives thereof, polyallylamine and derivatives thereof, polyvinylamine and derivatives thereof; polyamide-polyamine resin, polyamide epi Polyamide resins typified by chlorohydrin resins, etc .; polysaccharides typified by cationized starch, chitosan and chitosan derivatives; dicyandiamide formalin polycondensates, dicyandiamide derivatives typified by dicyandiamide diethylenetriamine polycondensates, etc .; polyamidines and polyamidines Derivatives; Dialkylamine epichlorohydrin addition polymer represented by dimethylamine epichlorohydrin addition polymer and the like; derivatives thereof; having a quaternary ammonium salt-substituted alkyl group Styrene polymers and copolymers with other monomers are also preferred.

  Specific examples of the polymer mordant include JP-A Nos. 48-28325, 54-74430, 54-124726, 55-22766, 55-142339, 60-23850, and 60. -23851, 60-23852, 60-23853, 60-57836, 60-60643, 60-118834, 60-122940, 60-122941, 60-122294 Nos. 60-235134, JP-A-1-161236, U.S. Pat.Nos. 2,484,430, 2,548,564, 3,148,061, 3,309,690, 4,115,124, 4,124,386, 4,193,800, 4,273,853 No. 4282305, No. 4450224, JP-A-1-1612. No. 6, No. 10-81064, No. 10-157277, No. 10-217601, JP-A Nos. 2001-138621, 2000-212235, No. 2001-138627, JP-A No. 8-174992, and JP-B-5 -35162, 5-35163, 5-35164, 5-88846, Japanese Patent Nos. 2648847, 2616677, and the like.

When the amount of the inorganic mordant and the amount of the organic mordant are used in combination, the ratio may be determined based on the balance between storage stability and bleeding, and the ratio of the inorganic mordant is 5% or more, preferably 10%. The above is preferable. Mordant amount is preferably from ^{0.01g / m 2 ~5g / m 2} , 0.1g / m 2 ~3g / m 2 is more preferable.

(Compound having two or more divalent or more metal atoms)
In the present invention, the coating liquid A (in the case where the coating layer in the present invention is formed using the coating liquid A and the coating liquid A ′, the coating liquid A and / or the coating liquid A ′), As a mordant, a compound having at least two or more divalent metal atoms in the molecule (hereinafter, this compound may be simply referred to as “metal-containing compound”) may be contained. The metal atom species having a valence of 2 or more includes all metal atoms having an valence of 2 or more and is not particularly limited. For example, magnesium, aluminum, calcium, scandium, titanium, vanadium, manganese, iron, nickel, chromium, copper, zinc, gallium, germanium, strontium, yttrium, zirconium, molybdenum, indium, barium, lanthanum, cerium, praseodymium, neodymium, Examples thereof include metal atoms such as samarium, europium, gadolinium, dysproprosium, erbium, ytterbium, hafnium, tungsten, and bismuth.

The divalent or higher metal atom type is preferably at least two or more selected from Group II to Group IV metal elements.
Preferred examples of the group II metal elements include beryllium, magnesium, calcium, strontium, barium, and zinc.
Preferred examples of the group III metal elements include scandium, yttrium, lanthanum, boron, aluminum, gallium, indium, and thallium.
Preferred examples of the group IV metal elements include titanium, zirconium, hafnium, and thorium.

  Among the above metal elements, the divalent or higher-valent metal atomic species in the metal-containing compound of the present invention are selected from aluminum, zirconium, titanium, lanthanoid, zinc, and magnesium from the viewpoint of the effect of improving ozone resistance and aging blur. At least two kinds of metals selected are preferable, and a combination of metal atoms containing at least zirconium and at least one kind selected from aluminum, titanium, lanthanoid, zinc, and magnesium is more preferable.

  Further, from the viewpoint of improving the production suitability, the compound having at least two or more divalent metal atoms in the molecule is preferably a water-soluble metal-containing compound. Here, the term “water-soluble” means that 0.5% by mass or more dissolves in water at room temperature, and the solubility is preferably 1.0% by mass or more, and more preferably 1.5% by mass or more. In addition, when it is oil-soluble, it can be emulsified and dispersed or added as an organic solution, and when it is a solid compound, it can be finely divided and added as a dispersion.

  Furthermore, in order to achieve both ozone resistance and aging blur and obtain a high level of improvement effect, the metal-containing compound is preferably a composite compound formed from at least a zirconium-containing compound and an aluminum-containing compound.

  Specific examples of the zirconium-containing compound include zirconium acetylacetonate, zirconyl acetate, zirconyl sulfate, ammonium zirconium carbonate, zirconyl stearate, zirconyl octylate, zirconyl nitrate, zirconium oxychloride, zirconium hydroxychloride, zirconyl lactate, and succinate. Examples include zirconyl acid, zirconyl oxalate, basic zirconium glycinate, and any mixture thereof.

  Specific examples of the aluminum-containing compound include aluminum halide, basic aluminum chloride (hereinafter also referred to as “polyaluminum chloride” or “basic polyaluminum hydroxide”), basic aluminum sulfate, basic aluminum nitrate, Examples include basic aluminum sulfamate, basic aluminum aluminum sulfonate, and any mixture thereof.

  Among the complex compounds containing zirconium and aluminum, the metal-containing compound is most preferably a complex compound formed using at least a basic zirconium compound and / or a basic aluminum compound.

As the basic zirconium compound that can be used for forming the metal-containing compound, a compound represented by the following general formula (I) is preferable.
Zr (OH) _x A _4-x ... general formula (I)
[In the above formula (I), A represents an amino acid, and x represents a number of 0 <x <4 (however, it is not necessary to be an integer). ]
Among the basic zirconium compounds represented by the general formula (I), basic zirconium-amino acid gel, zirconium hydroxide-amino acid gel, basic zirconium carbonate-amino acid gel, and a mixture thereof are preferable. These gels are preferably a reaction product of a water-soluble salt of the amino acid and a water-soluble zirconium salt, or a water-soluble salt of the amino acid and a zirconium hydroxy salt.
Further, as the zirconium compound, zirconium oxy salt, zirconium hydroxy salt, trioxodizylconyl hydroxy salt, and a mixture thereof are preferable.

When the basic zirconium compound is a basic zirconium carbonate gel, the basic zirconium carbonate is preferably a compound represented by the following general formula (II).
Zr (OH) _4-2x (CO ₃ ) _x General formula (II)
[In the above formula (II), x represents a number of 0 <x <2 (not necessarily an integer). ]
Among the basic zirconium carbonate gels represented by the general formula (II), those which are reaction products of sodium carbonate and zirconium oxy salt or zirconium hydroxy salt are preferable.
The general formula (I) and the general formula (II) are simplified, the compound also exists as a polymer of the general formula (I) and the general formula (II), and the ligand and / or water is present. Can be combined. In the general formula (I) and the general formula (II), the OH group can be expressed as an oxide (oxy group).

Acidic or cationic zirconium compounds that can be used to form metal-containing compounds are both zirconium oxy and zirconium hydroxy salts (also called zirconium and zirconyl hydroxy salts). These compounds can be represented by the following general formula (III).
ZrO (OH) _2-nz B _z ... General formula (III)
[In the above formula (III), z is about 0.9 to 2 (but not necessarily an integer), n is the valence of B, 2-nz> 0, and B is a halide. , Nitrates, sulfamates, sulfates and mixtures thereof. ]

The basic aluminum compound that can be used to form the metal-containing compound can be represented by the following general formula (IV).
Al ₂ (OH) _6-nx B _x General formula (IV)
[In the above formula (IV), B is selected from the group consisting of halides, nitrates, sulfamates, sulfates and mixtures thereof. x represents a number of 0 <x <6 (not necessarily an integer), (6-nx) represents a number of 0 or more, and n represents a valence of B. ]
That is, the general formula (IV) represents a polymer or complex, a basic aluminum compound containing a water coordination and / or binding molecule, and a mixture thereof.
Among the basic aluminum compounds of general formula (IV), basic aluminum chloride in which B is a chlorine atom and x is a number of 2 <x <5 (it is not necessary to be an integer) in the above formula (IV) ;
Al ₂ (OH) ₂ Cl _{4 to} Al ₂ (OH) ₅ Cl
Is particularly preferred.

  In the above compound containing zirconium and aluminum, the molar ratio of zirconium to aluminum is preferably 1/100 to 100/1, more preferably 3/100 to 100/3, and particularly 5/100 to 100. Most preferred is / 5.

As a preferred embodiment of the compound having at least two or more divalent metal atoms in the molecule, there can be mentioned a complex using an organic compound in addition to the above metal atom types. As the organic compound, those having at least one oxygen atom, sulfur atom, nitrogen atom, phosphorus atom and the like having a lone pair of electrons are preferable so that they can interact with metal atom species. Examples of such organic compounds include at least —CO ₂ ⁻ , —SO ₃ ⁻ , —OSO ₃ ⁻ , —PO ₄ ^m− (where m is an integer of 1 to 3), —PO ₃ ²⁻ , − PO ₂ ^-, -O ^- organic compounds having become get groups anionic group selected from. The organic compound having a group that can be an anionic group may further have a nitrogen atom.

Specific examples of the organic compound include amino acids, aliphatic carboxylic acid compounds, betaine compounds (for example, carbobetaine, sulfobetaine, phosphopetine compounds, etc.), aromatic carboxylic acid compounds, heterocyclic carboxylic acid compounds, Aliphatic diketone compounds, aliphatic sulfonic acid compounds, aromatic sulfonic acid compounds, heterocyclic sulfonic acid compounds, aliphatic phosphoric acid compounds, aromatic phosphoric acid compounds, heterocyclic phosphoric acid compounds, aliphatic sulfinic acid compounds, aromatic Group sulfinic acid compounds, heterocyclic sulfinic acid compounds, amine compounds (such as hydroxy group-containing amine compounds), amide compounds, urea compounds, and the like.
These may be low molecular compounds or high molecular compounds which may have a substituent in the partial skeleton.

Specific examples of the compound having two or more kinds of divalent or higher metal atoms are shown below, but the invention is not limited to these compounds.
(1) zirconium-chloro-glycine-hydroxyaluminum complex, (2) octaaluminum-zirconium-pentachloride-tricosahydride, (3) tetraaluminum-zirconium-tetrachloride-dodecahydroxide, (4) tetraaluminum - zirconium - trichloride - tridecafluoro hydroxide, (5) octa aluminum - zirconium - Okutakurorido - Aiko Sa hydroxide, (6) basic aluminum chloride (Al ₂ (OH) ₅ Cl) a mixture of zirconium lactate, (7 ) Complex of basic aluminum chloride (Al ₂ (OH) ₅ Cl) and zirconyl acetate, (8) Complex of basic aluminum chloride (Al ₂ (OH) ₅ Cl) and basic zirconium glycine, (9) Chloride Aluminum and basic zirconium Complex of melanin and zinc sulfate, (10) a complex of basic zirconium glycine lanthanum and basic aluminum chloride _{(Al 2 (OH) 5 Cl} ), (11) a basic aluminum chloride (Al ₂ (OH) ₅ Cl), zirconium oxychloride and hydroxyethyliminodiacetic acid, (12) basic aluminum chloride (Al ₂ (OH) ₅ Cl), zirconium oxychloride and betaine, (13) myristate-methacrylato-chloro Hydroxo-methanolato-isopropanolato-zirconium-aluminum, (14) 3-aminopropionato-chlorohydroxo-methanolato-zirconium-aluminum and the like.

  In preparing the inkjet recording material of the present invention, (1) a compound having at least two or more divalent metal atoms in the molecule is formed in advance, and then the metal-containing compound is applied to the coating liquid A (in the present invention). When the coating layer is formed using the coating solution A and the coating solution A ′, it may be used by adding to the coating solution A and / or the coating solution A ′, or (2 ) In the stage of preparing the coating solution A (the coating solution A and / or the coating solution A ′ when the coating layer in the present invention is formed using the coating solution A and the coating solution A ′) Each metal-containing compound (for example, a combination of a zirconium-containing compound and an aluminum-containing compound) capable of forming a compound (composite) having at least two or more divalent metals in the molecule of the present invention Or separately In the process of preparing the coating liquid A (the coating liquid A and / or the coating liquid A ′ when the coating layer in the present invention is formed using the coating liquid A and the coating liquid A ′). You may use what was formed by making it react.

  In addition, the compound having at least two kinds of metal atoms having at least two valences in the molecule is usually heated by mixing each metal-containing compound capable of forming the target metal-containing compound or as necessary. Along with this, it can be manufactured. Here, the compound of each metal may be in the form of a salt by combining with a strong acid or a weak acid, or may be in the form of a hydroxide, a halohydroxide, a complex, or the like, and formed by reacting them. The composite compound of the present invention can be contained in the ink receiving layer of an ink jet recording medium. Specific examples of such metal salts, hydroxides, halohydroxides, and complexes are listed below. That is,

Calcium acetate, calcium chloride, calcium formate, calcium sulfate, barium acetate, barium sulfate, barium phosphate, manganese chloride, manganese acetate, manganese formate dihydrate, manganese ammonium sulfate hexahydrate, cupric chloride, ammonium chloride Copper (II) dihydrate, copper sulfate, cobalt chloride, cobalt thiocyanate, cobalt sulfate, nickel sulfate hexahydrate, nickel chloride hexahydrate, nickel acetate tetrahydrate, nickel ammonium sulfate hexahydrate , Nickel amidosulfate tetrahydrate, aluminum sulfate, aluminum alum, aluminum sulfite, aluminum thiosulfate, polyaluminum chloride, basic aluminum lactate, basic aluminum sulfate, basic aluminum nitrate, basic aluminum sulfamate, basic formic acid Aluminum, basic Aluminum nitrate, basic aluminum glycinate, aluminum nitrate nonahydrate, aluminum chloride hexahydrate, ferrous bromide, ferrous chloride, ferric chloride, ferrous sulfate, ferric sulfate, phenol Zinc sulfonate, zinc bromide, zinc chloride, zinc nitrate hexahydrate, zinc sulfate, titanium tetrachloride, tetraisopropyl titanate, titanium acetylacetonate, titanium lactate, zirconium acetylacetonate, zirconyl acetate, zirconyl sulfate, zirconium carbonate Ammonium, zirconyl stearate, zirconyl octylate, zirconyl nitrate, zirconyl lactate, zirconyl succinate, zirconyl oxalate, ammonium zirconium acetate, potassium zirconium carbonate, sodium zirconium lactate, basic zirconium glycinate, zirconyl oxychloride , Hydroxy zirconium chloride, chromium acetate, chromium sulfate, magnesium sulfate, magnesium chloride hexahydrate, magnesium citrate nonahydrate, sodium phosphotungstate, sodium tungsten citrate, 12 tungstophosphoric acid n hydrate, 12 Tungstosilicic acid 26 hydrate, molybdenum chloride, 12 molybdophosphoric acid n hydrate, gallium nitrate, germanium nitrate, strontium nitrate, yttrium acetate, yttrium chloride, yttrium nitrate, indium nitrate, lanthanum nitrate, lanthanum chloride, lanthanum acetate, Lanthanum benzoate, cerium chloride, cerium sulfate, cerium octylate, praseodymium nitrate, neodymium nitrate, samarium nitrate, europium nitrate, gadolinium nitrate, dysprosium nitrate, erbium nitrate, yttrium nitrate Rubiumu, hafnium chloride, and bismuth nitrate.

  Among these, aluminum sulfate, aluminum alum, aluminum sulfite, aluminum thiosulfate, polyaluminum chloride, basic aluminum lactate, basic aluminum sulfate, basic aluminum nitrate, basic aluminum sulfamate, basic aluminum formate, basic acetic acid Aluminum-containing compounds such as aluminum, basic aluminum glycinate, aluminum nitrate nonahydrate, aluminum chloride hexahydrate; titanium-containing compounds such as titanium tetrachloride, tetraisopropyl titanate, titanium acetylacetonate, titanium lactate; and Zirconium acetylacetonate, zirconyl acetate, zirconyl sulfate, ammonium zirconium carbonate, zirconyl stearate, zirconyl octylate, zirconyl nitrate, zirconyl lactate Zirconyl succinate, zirconyl oxalate, zirconium ammonium acetate, potassium zirconium carbonate, sodium zirconium lactate, basic zirconium glycinate, zirconium oxychloride, hydroxy zirconium chloride and the like are preferred, especially basic zirconium and / or basic Aluminum salts are preferred.

In the ink receiving layer of the present invention, the content of the compound having at least two kinds of divalent or higher metal atoms in the molecule is 0.01 g / m ² in order to further improve the image blur and light resistance. is preferably to 20 g / m ^2, the content is more preferably ^{0.1g / m 2 ~15g / m 2} , and most preferably an ^{0.5g / m 2 ~10g / m 2} .
If the content of the complex is 0.01 g / m ² or more, the effect of improving image blurring and light resistance can be more effectively achieved. If the content is 20 g / m ² or less, Aggregation when using fine particles can be more effectively prevented, and the glossiness of the recording material can be further improved.

(Other ingredients)
The ink receiving layer of the present invention (that is, the coating liquid A, the coating liquid A ′, and / or the coating liquid B) may be further added with various known additives such as acids, ultraviolet absorbers, and antioxidants as necessary. Agent, optical brightener, monomer, polymerization initiator, polymerization inhibitor, anti-bleeding agent, preservative, viscosity stabilizer, antifoaming agent, surfactant, antistatic agent, matting agent, anti-curl agent, water resistance agent Etc. can be contained.

  In the present invention, the ink receiving layer (that is, the coating liquid A, the coating liquid A ′, and / or the coating liquid B) may contain an acid. By adding an acid, the surface pH of the ink receiving layer is adjusted to 3 to 8, preferably 4 to 6. This is preferable because yellowing resistance of the white background portion is improved. The surface pH is measured by the A method (coating method) of the surface PH measurement defined by the Japan Paper Pulp Technology Association (J.TAPPI). For example, the measurement can be performed by using a paper PH measurement set “Type MPC” manufactured by Kyoritsu Riken Co., Ltd. corresponding to the method A.

Specific examples of acids include formic acid, acetic acid, glycolic acid, oxalic acid, propionic acid, malonic acid, succinic acid, adipic acid, maleic acid, malic acid, tartaric acid, citric acid, benzoic acid, phthalic acid, isophthalic acid , Glutaric acid, gluconic acid, lactic acid, aspartic acid, glutamic acid, salicylic acid, salicylic acid metal salts (salts such as Zn, Al, Ca, Mg), methanesulfonic acid, itaconic acid, benzenesulfonic acid, toluenesulfonic acid, trifluoromethanesulfone Acid, styrenesulfonic acid, trifluoroacetic acid, barbituric acid, acrylic acid, methacrylic acid, cinnamic acid, 4-hydroxybenzoic acid, aminobenzoic acid, naphthalenedisulfonic acid, hydroxybenzenesulfonic acid, toluenesulfinic acid, benzenesulfinic acid, Sulfanilic acid, sulfamic acid, α-le Rucinic acid, β-resorcinic acid, γ-resorcinic acid, gallic acid, phloroglicin, sulfosalicylic acid, ascorbic acid, erythorbic acid, bisphenolic acid, hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, polyphosphoric acid, boric acid, boronic acid and the aforementioned Examples include organic and inorganic mordants that are acidic. The amount of these acids added may be determined so that the surface PH of the ink receiving layer is 3-8.
The above acids can be metal salts (eg sodium, potassium, calcium, cesium, zinc, copper, iron, aluminum, zirconium, lanthanum, yttrium, magnesium, strontium, cerium, etc.) or amine salts (eg ammonia, triethylamine, tri Butylamine, piperazine, 2-methylpiperazine, polyallylamine, etc.).

In the present invention, the ink receiving layer (that is, the coating liquid A, the coating liquid A ′, and / or the coating liquid B) contains a storage stability improver such as an ultraviolet absorbent, an antioxidant, or a bleeding inhibitor. It is preferable.
These ultraviolet absorbers, antioxidants, and anti-bleeding agents include alkylated phenol compounds (including hindered phenol compounds), alkylthiomethylphenol compounds, hydroquinone compounds, alkylated hydroquinone compounds, tocopherol compounds, and aliphatics having a thioether bond. , Aromatic and / or heterocyclic compounds, bisphenol compounds, O-, N- and S-benzyl compounds, hydroxybenzyl compounds, triazine compounds, phosphonate compounds, acylaminophenol compounds, ester compounds, amide compounds, ascorbic acid, amines Antioxidants, 2- (2-hydroxyphenyl) benzotriazole compounds, 2-hydroxybenzophenone compounds, acrylates, water-soluble or hydrophobic metal salts, organometallic compounds, metal complexes, hinders Amine compounds (including TEMPO compounds), 2- (2-hydroxyphenyl) 1,3,5-triazine compounds, metal deactivators, phosphite compounds, phosphonite compounds, hydroxyamine compounds, nitrone compounds, peroxides Scavenger, polyamide stabilizer, polyether compound, basic auxiliary stabilizer, nucleating agent, benzofuranone compound, indolinone compound, phosphine compound, polyamine compound, thiourea compound, urea compound, hydrazide compound, amidine compound, sugar compound, hydroxybenzoic acid A compound, a dihydroxybenzoic acid compound, a trihydroxybenzoic acid compound, and the like.

  Among these, alkylated phenol compounds, aliphatic, aromatic and / or heterocyclic compounds having a thioether bond, bisphenol compounds, ascorbic acid, amine-based antioxidants, water-soluble or hydrophobic metal salts, organometallic compounds , Metal complexes, hindered amine compounds, hydroxyamine compounds, polyamine compounds, thiourea compounds, hydrazide compounds, hydroxybenzoic acid compounds, dihydroxybenzoic acid compounds, trihydroxybenzoic acid compounds, and the like are preferable.

  Specific examples of the compound include JP-A No. 2002-36717, JP-A No. 2002-86904, Japanese Patent Application No. 2002-13005, JP-A No. 10-182621, JP-A No. 2001-260519, JP-B No. 4-34953, JP-B-4-34513, JP-A-11-170686, JP-B-4-34512, EP1138509, JP-A-60-67190, JP-A-7-276808, JP-A-2001-94829, JP-A-47-. No. 10537, No. 58-111942, No. 58-212844, No. 59-19945, No. 59-46646, No. 59-109055, No. 63-53544, No. 36-10466, No. 42-26187. 48-30492, 48-31255, 48-41572, 48-54965, 50-10726, U.S. Pat.Nos. 2,719,086, 3,707,375, 3,754,919, 4,220,711,

Japanese Patent Publication Nos. 45-4699, 54-5324, European Published Patent Nos. 223739, 309401, 309402, 3105301, 310552, 459416, German Published Patent No. 3435443, Kaisho 54-48535, 60-107384, 60-107383, 60-125470, 60-125471, 60-125472, 60-287485, 60-287486, 60-287487, 60-287488, 61-160287, 61-18854, 61-2111079, 62-146678, 62-146680, 62-146679, 62- No. 282885, No. 62-262047, No. 63-051174, Nos. 63-89877, 63-88380 same issue, same 66-88381 JP, same 63-113536 issue,

63-163351, 63-203372, 63-224989, 63-251282, 63-267594, 63-182484, JP-A-1-239282, JP-A-2-262654, 2-71262, 3-121449, 4-291865, 4-291684, 5-611166, 5-119449, 5-188687, 5-188686, 5 No. 110490, No. 5-110437, No. 5-170361, No. 48-43295, No. 48-33212, US Pat. Nos. 4,814,262, No. 4,980,275, and the like. .

The other components may be used alone or in combination of two or more. These other components may be added after being water-solubilized, dispersed, polymer-dispersed, emulsified or oil-dropped, or may be encapsulated in microcapsules. In the ink jet recording medium of the present invention, the addition amount of the other components is preferably 0.01 to 10 g / m ² .

  Further, for the purpose of improving the dispersibility of the inorganic fine particles, the inorganic surface may be treated with a silane coupling agent. Examples of the silane coupling agent include an organic functional group (for example, vinyl group, amino group (primary to tertiary amino group, quaternary ammonium base), epoxy group, mercapto, in addition to the site for coupling treatment. Group, a chloro group, an alkyl group, a phenyl group, an ester group, a thioether group, etc.).

In the present invention, the ink receiving layer coating solution (that is, coating solution A, coating solution A ′, and / or coating solution B) preferably contains a surfactant. As the surfactant, any of cationic, anionic, nonionic, amphoteric, fluorine, and silicon surfactants can be used.
Examples of the nonionic surfactant include polyoxyalkylene alkyl ethers and polyoxyalkylene alkyl phenyl ethers (for example, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene Ethylene nonylphenyl ether), oxyethylene / oxypropylene block copolymer, sorbitan fatty acid esters (for example, sorbitan monolaurate, sorbitan monooleate, sorbitan trioleate, etc.), polyoxyethylene sorbitan fatty acid esters (for example, polyoxyethylene) Sorbitan monolaurate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan Lyolate, etc.), polyoxyethylene sorbitol fatty acid esters (eg, polyoxyethylene sorbitol tetraoleate), glycerin fatty acid esters (eg, glycerol monooleate), polyoxyethylene glycerin fatty acid esters (polyoxymonostearate) Ethylene glycerin, monooleic acid polyoxyethylene glycerin, etc.), polyoxyethylene fatty acid esters (polyethylene glycol monolaurate, polyethylene glycol monooleate, etc.), polyoxyethylene alkylamine, acetylene glycols (eg, 2, 4, 7) , 9-tetramethyl-5-decyne-4,7-diol, and ethylene oxide adducts, propylene oxide adducts, etc. of the diols), and polyoxy Ruki alkylene alkyl ethers are preferable. The nonionic surfactant can be used in the first coating solution and the second coating solution. Moreover, the said nonionic surfactant may be used independently and may use 2 or more types together.

  Examples of the amphoteric surfactant include amino acid type, carboxyammonium betaine type, sulfoammonium betaine type, ammonium sulfate betaine type, imidazolium betaine type and the like. For example, US Pat. No. 3,843,368, JP, JP-A-59-49535, JP-A-63-236546, JP-A-5-303205, JP-A-8-262742, JP-A-10-282619, JP-A-2514194, JP-A-2759597, JP-A-2000-351269, etc. Can be used preferably. Of the amphoteric surfactants, the amino acid type, carboxyammonium betaine type, and sulfoneammonium betaine type are preferable. The amphoteric surfactants may be used alone or in combination of two or more.

Examples of the anionic surfactant include fatty acid salts (for example, sodium stearate, potassium oleate), alkyl sulfate esters (for example, sodium lauryl sulfate, triethanolamine lauryl sulfate), and sulfonates (for example, sodium dodecylbenzene sulfonate). Alkyl sulfosuccinate (for example, sodium dioctyl sulfosuccinate), alkyl diphenyl ether disulfonate, alkyl phosphate, and the like.
Examples of the cationic surfactant include alkylamine salts, quaternary ammonium salts, pyridinium salts, imidazolium salts, and the like.

Examples of the fluorosurfactant include compounds derived from an intermediate having a perfluoroalkyl group using a method such as electrolytic fluorination, telomerization, or oligomerization.
Examples include perfluoroalkyl sulfonates, perfluoroalkyl carboxylates, perfluoroalkyl ethylene oxide adducts, perfluoroalkyl trialkyl ammonium salts, perfluoroalkyl group-containing oligomers, perfluoroalkyl phosphates, and the like.

  As the silicon-based surfactant, silicon oil modified with an organic group is preferable, and a structure in which a side chain of a siloxane structure is modified with an organic group, a structure in which both ends are modified, and a structure in which one end is modified can be taken. Examples of the organic group modification include amino modification, polyether modification, epoxy modification, carboxyl modification, carbinol modification, alkyl modification, aralkyl modification, phenol modification, and fluorine modification.

  In the present invention, the content of the surfactant is preferably 0.001 to 2.0% with respect to the ink receiving layer coating liquid (that is, the coating liquid A, the coating liquid A ′, and / or the coating liquid B). 0.01 to 1.0% is more preferable. Further, when coating is performed using two or more liquids as the ink receiving layer coating liquid, it is preferable to add a surfactant to each coating liquid.

In the present invention, the ink receiving layer (that is, the coating liquid A, the coating liquid A ′, and / or the coating liquid B) preferably contains a high-boiling organic solvent for preventing curling. The high-boiling organic solvent is an organic compound having a boiling point of 150 ° C. or higher at normal pressure, and is a water-soluble or hydrophobic compound. These may be liquid or solid at room temperature, and may be low molecules or polymers.
Specifically, aromatic carboxylic acid esters (for example, dibutyl phthalate, diphenyl phthalate, phenyl benzoate, etc.), aliphatic carboxylic acid esters (for example, dioctyl adipate, dibutyl sebacate, methyl stearate, dibutyl maleate) , Dibutyl fumarate, triethyl acetyl citrate, etc.), phosphate esters (eg, trioctyl phosphate, tricresyl phosphate, etc.), epoxies (eg, epoxidized soybean oil, epoxidized fatty acid methyl, etc.), alcohols (eg, stearyl) Alcohol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, glycerol, diethylene glycol monobutyl ether (DEGMBE), triethylene glycol monobutyl ether, glycerol Methyl ether, 1,2,3-butanetriol, 1,2,4-butanetriol, 1,2,4-pentanetriol, 1,2,6-hexanetriol, thiodiglycol, triethanolamine, polyethylene glycol, etc. ), Vegetable oils (eg, soybean oil, sunflower oil, etc.) and higher aliphatic carboxylic acids (eg, linoleic acid, oleic acid, etc.).

<Support>
As the support of the present invention, any of a transparent support made of a transparent material such as plastic and an opaque support made of an opaque material such as paper can be used. In order to make use of the transparency of the ink receiving layer, it is preferable to use a transparent support or a highly glossy opaque support. Further, a read-only optical disk such as a CD-ROM or DVD-ROM, a write-once optical disk such as a CD-R or DVD-R, or a rewritable optical disk may be used as a support to provide an ink receiving layer on the label surface side. it can.

As a material that can be used for the transparent support, a material that is transparent and can withstand radiant heat when used in an OHP or a backlight display is preferable. Examples of the material include polyesters such as polyethylene terephthalate (PET); polysulfone, polyphenylene oxide, polyimide, polycarbonate, polyamide and the like. Of these, polyesters are preferable, and polyethylene terephthalate is particularly preferable.
Although there is no restriction | limiting in particular as thickness of the said transparent support body, 50-200 micrometers is preferable at the point which is easy to handle.

  As the highly glossy opaque support, one having a glossiness of 40% or more on the surface on which the ink receiving layer is provided is preferable. The glossiness is a value determined according to the method described in JIS P-8142 (75-degree specular gloss test method for paper and paperboard). Specifically, the following supports are mentioned.

For example, high gloss paper support such as art paper, coated paper, cast coated paper, baryta paper used for silver salt photographic support, etc .; polyesters such as polyethylene terephthalate (PET), nitrocellulose, cellulose acetate , Cellulose esters such as cellulose acetate butyrate, and plastic films such as polysulfone, polyphenylene oxide, polyimide, polycarbonate, and polyamide are made opaque by adding a white pigment or the like (surface calendering may be applied). Glossy film; or a support in which a polyolefin coating layer containing or not containing a white pigment is provided on the surface of a highly glossy film containing the various paper supports, the transparent support or the white pigment. Etc.
A white pigment-containing foamed polyester film (for example, foamed PET containing polyolefin fine particles and forming voids by stretching) can also be suitably exemplified. Furthermore, resin-coated paper used for silver salt photographic printing paper is also suitable.

  Although there is no restriction | limiting in particular also about the thickness of the said opaque support body, 50-300 micrometers is preferable at the point of handleability.

  The surface of the support may be subjected to corona discharge treatment, glow discharge treatment, flame treatment, ultraviolet irradiation treatment or the like in order to improve wettability and adhesion.

Next, the base paper used for the resin-coated paper will be described in detail.
The base paper is made from wood pulp as a main raw material and, if necessary, paper using synthetic pulp such as polypropylene or synthetic fibers such as nylon or polyester in addition to wood pulp. As the wood pulp, any of LBKP, LBSP, NBKP, NBSP, LDP, NDP, LUKP, and NUKP can be used, but more LBKP, NBSP, LBSP, NDP, and LDP with a larger amount of short fibers are used. preferable.
However, the ratio of LBSP and / or LDP is preferably 10% by mass or more and 70% by mass or less.

  The pulp is preferably a chemical pulp (sulfate pulp or sulfite pulp) with few impurities, and a pulp having a whiteness improved by bleaching is also useful.

  In the base paper, sizing agents such as higher fatty acids and alkyl ketene dimers, white pigments such as calcium carbonate, talc and titanium oxide, paper strength enhancing agents such as starch, polyacrylamide and polyvinyl alcohol, fluorescent whitening agents, polyethylene glycols A water retaining agent such as a dispersant, a softening agent such as a quaternary ammonium, and the like can be appropriately added.

  The freeness of the pulp used for papermaking is preferably 200 to 500 ml as defined by CSF, and the fiber length after beating is a 24 mesh residual mass% and a 42 mesh residual as defined in JIS P-8207. 30 to 70% of the sum with the mass% of is preferable. In addition, it is preferable that the mass% of 4 mesh remainder is 20 mass% or less.

The basis weight of the base paper is preferably 30 to 250 g, and particularly preferably 50 to 200 g. The thickness of the base paper is preferably 40 to 250 μm. The base paper can be given a high smoothness by calendering at the paper making stage or after paper making. The density of the base paper is generally 0.7 to 1.2 g / m ₂ (JIS P-8118).
Furthermore, the base paper stiffness is preferably 20 to 200 g under the conditions specified in JIS P-8143.

A surface sizing agent may be applied to the surface of the base paper. As the surface sizing agent, a sizing agent similar to the size that can be added to the base paper can be used.
The pH of the base paper is preferably 5 to 9 when measured by a hot water extraction method defined in JIS P-8113.

  The polyethylene covering the front and back surfaces of the base paper is mainly low-density polyethylene (LDPE) and / or high-density polyethylene (HDPE), but some other LLDPE, polypropylene, etc. can also be used.

  In particular, the polyethylene layer on the side that forms the ink receiving layer is added with rutile or anatase type titanium oxide, fluorescent whitening agent, ultramarine, and polyethylene, as is widely done in photographic paper. Those having improved whiteness and hue are preferred. Here, as a titanium oxide content, about 3-20 mass% is preferable with respect to polyethylene, and 4-13 mass% is more preferable. Although the thickness of a polyethylene layer does not have limitation in particular, 10-50 micrometers is suitable for both front and back layers. Further, an undercoat layer can be provided on the polyethylene layer in order to provide adhesion to the ink receiving layer. As the undercoat layer, aqueous polyester, gelatin and PVA are preferable. Moreover, as thickness of this undercoat layer, 0.01-5 micrometers is preferable.

  Polyethylene-coated paper can be used as glossy paper, or when it is melt-extruded onto the surface of the base paper and coated, the matte surface or silky surface that can be obtained with ordinary photographic printing paper by so-called molding Can also be used.

A back coat layer can be provided on the support, and examples of components that can be added to the back coat layer include a white pigment, an aqueous binder, and other components.
Examples of white pigments contained in the backcoat layer include light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, and aluminum silicate. , Diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica, colloidal alumina, pseudoboehmite, aluminum hydroxide, alumina, lithopone, zeolite, hydrous halloysite, magnesium carbonate, magnesium hydroxide, white inorganic pigment, styrene And organic pigments such as polyethylene plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, urea resins, and melamine resins.

Examples of the aqueous binder used in the backcoat layer include styrene / maleate copolymer, styrene / acrylate copolymer, polyvinyl alcohol, silanol-modified polyvinyl alcohol, starch, cationized starch, casein, gelatin, carboxy Examples thereof include water-soluble polymers such as methyl cellulose, hydroxyethyl cellulose, and polyvinyl pyrrolidone, and water-dispersible polymers such as styrene butadiene latex and acrylic emulsion.
Examples of other components contained in the backcoat layer include an antifoaming agent, an antifoaming agent, a dye, a fluorescent brightening agent, a preservative, and a water-proofing agent.

≪Preparation of inkjet recording material≫
The ink jet recording material of the present invention can be produced by forming the ink receiving layer on the support.
For example, a method for producing an ink jet recording material having an ink receiving layer on a support, wherein the ink receiving layer forms a coating layer on the support using at least coating liquid A containing fine particles and a water-soluble resin. Then, after the formed coating layer exhibits reduced-rate drying, a coating solution B containing a substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule is formed on the coating layer. The ink-jet recording material can be suitably produced by using a method for producing an ink-jet recording material characterized by being formed by coating. A preferred embodiment of the method for producing the ink jet recording material is as described in the above-mentioned item “Inkjet recording material”.
Hereinafter, an example of a method for producing an inkjet recording material in the case where the coating layer in the present invention is formed using only the coating liquid A will be described.

<Preparation of coating liquid A>
In the present invention, the coating liquid A containing at least fine particles (for example, vapor phase method silica) and a water-soluble resin (for example, polyvinyl alcohol) can be prepared, for example, as follows.
That is, the vapor phase method silica fine particles and a dispersant are added to water (for example, 10 to 20% by mass of silica fine particles in water), and a high-speed rotating wet colloid mill (for example, “Clairemix” manufactured by M Technique Co., Ltd.). )), For example, at a high speed of 10,000 rpm (preferably 5000 to 20000 rpm), for example, for 20 minutes (preferably 10 to 30 minutes) and then dispersed, and then a crosslinking agent (for example, boric acid), polyvinyl alcohol ( PVA) aqueous solution (for example, PVA having a mass of about 1/3 of the above-mentioned vapor phase silica) is added, and a compound having at least two or more divalent metal atoms in the molecule (for example, Basic polyaluminum hydroxide) can be added and dispersed under the same rotational conditions as described above. The obtained coating liquid is in a uniform sol state, and a porous ink-receiving layer having a three-dimensional network structure can be formed by coating this on a support by the following coating method and drying it.

In addition, the preparation of the aqueous dispersion composed of the above-mentioned vapor phase method silica and a dispersant may be carried out by preparing a vapor phase method silica aqueous dispersion in advance and adding the aqueous dispersion to the aqueous dispersant solution. The aqueous solution may be added to the vapor phase silica aqueous dispersion, or may be mixed simultaneously. Further, instead of vapor phase silica aqueous dispersion, powder vapor phase silica may be used and added to the aqueous dispersant as described above.
After mixing said vapor phase silica and a dispersing agent, the mixed liquid is refined using a disperser, whereby an aqueous dispersion having an average particle diameter of 50 to 300 nm can be obtained. As a disperser used for obtaining the aqueous dispersion, various types of conventionally known dispersers such as a high-speed rotating disperser, a medium stirring disperser (ball mill, sand mill, etc.), an ultrasonic disperser, a colloid mill disperser, and a high pressure disperser Although a disperser can be used, a stirrer-type disperser, a colloid mill disperser, or a high-pressure disperser is preferable from the viewpoint that the formed fine particles are efficiently dispersed.

  Moreover, water, an organic solvent, or these mixed solvents can be used as a solvent in each process. Examples of the organic solvent that can be used for this coating include alcohols such as methanol, ethanol, n-propanol, i-propanol, and methoxypropanol, ketones such as acetone and methyl ethyl ketone, tetrahydrofuran, acetonitrile, ethyl acetate, and toluene. It is done.

In addition, a chaotic polymer can be used as the dispersant. Examples of the chaotic polymer include the aforementioned organic mordants. It is also preferable to use a silane coupling agent as the dispersant.
The amount of the dispersant added to the fine particles is preferably 0.1% to 30%, more preferably 1% to 10%.

<Preparation of coating liquid B>
The coating liquid B can be prepared by dissolving the aforementioned specific compound by a known method. Furthermore, when the coating liquid B contains other components such as fine particles and a water-soluble resin, these components can be dissolved or dispersed by the same method as the preparation of the coating liquid A.

<Formation of ink receiving layer>
The ink receiving layer
(1) On the support, a coating layer is formed by applying a coating solution A containing fine particles and a water-soluble resin,
(2) The coating layer formed on the support can be formed by coating the coating layer with the coating liquid B containing the specific compound after the coating layer has been reduced at a reduced rate.

(Formation of coating layer to drying)
First, the coating liquid A is applied on the above-described support to form a coating layer.
The coating liquid A is applied by a known coating method using, for example, a slide bead coater, an extrusion die coater, an air doctor coater, a bread coater, a rod coater, a knife coater, a squeeze coater, a reverse roll coater, a bar coater, or the like. be able to.
As a moisture application quantity of the coating liquid A, 100-300 g / m < ² > is preferable and 150-250 g / m < ² > is more preferable.
Moreover, as solid content application quantity of the microparticles | fine-particles of the coating liquid A, 10-25 g / m < ² > is preferable and 12-20 g / m < ² > is more preferable.

Further, the coating layer formed on the support is dried until it shows reduced drying. Although there is no limitation in particular as drying conditions, The conditions dried for 1 to 15 minutes at 40-110 degreeC are preferable, and the conditions dried for 2 to 10 minutes at 50-100 degreeC are more preferable. Moreover, in order to fix the said coating layer, you may perform low temperature drying (preferably -10 degreeC-15 degreeC for 10 second-1 minute) immediately after application | coating and before the drying by the said conditions.
The details of the reduction rate drying are as described in the above <Ink receiving layer>.

(Application of coating liquid B to drying)
After the coating layer shows reduced-rate drying, the coating solution B is coated on the coating layer.
Application of coating liquid B is, for example, an automatic coating machine (manufactured by TECHNO SUPPLY Co.), curtain flow coater, extrusion die coater, air doctor coater, bread coater, rod coater, knife coater, squeeze coater, reverse roll coater, It can be performed by a known coating method using a bar coater or the like. Among them, it is preferable to use a method in which the coater does not directly contact an already formed coating layer, such as an extrusion die coater, a curtain flow coater, a bar coater or the like.
As a moisture application quantity of the coating liquid B, 10-60 g / m < ² > is preferable and 15-30 g / m < ² > is more preferable.
Moreover, when the coating liquid B contains colloidal silica, 0.2-5.0 g / m < ² > is preferable as a solid content application amount, and 0.5-2.0 g / m < ² > is more preferable.

As a result, the ink receiving layer is formed on the support. The drying condition of the formed ink receiving layer is preferably a condition of drying at 40 to 110 ° C. for 1 to 10 minutes, and more preferably a condition of drying at 50 to 100 ° C. for 2 to 7 minutes.
The inorganic mordant is preferably present in the entire ink receiving layer or in the vicinity of the ink receiving layer surface.

<Other processes>
After the ink receiving layer is formed on the support, the ink receiving layer is subjected to, for example, super calender, gloss calendar, etc., and calendering through the roll nip under heat and pressure, thereby providing surface smoothness, glossiness, It is possible to improve transparency and coating strength. However, since the calendar process may cause a decrease in the porosity (that is, the ink absorbability may be decreased), it is necessary to set conditions under which the decrease in the porosity is small.

As roll temperature in the case of performing a calendar process, 30-150 degreeC is preferable and 40-100 degreeC is more preferable.
Moreover, as linear pressure between rolls at the time of a calendar process, 50-400 kg / cm is preferable and 100-200 kg / cm is more preferable.

The thickness of the ink receiving layer needs to be determined in relation to the void ratio in the layer since it needs to have an absorption capacity sufficient to absorb all droplets in the case of inkjet recording. For example, if the ink amount is 8 nL / mm ² and the porosity is 60%, a film having a layer thickness of about 15 μm or more is required.
Considering this point, in the case of ink jet recording, the layer thickness of the ink receiving layer is preferably 10 to 50 μm.

Further, the pore diameter of the ink receiving layer is preferably 0.005 to 0.030 μm, more preferably 0.01 to 0.025 μm in terms of median diameter.
The porosity and pore median diameter can be measured using a mercury porosimeter (trade name “Pore Sizer 9320-PC2” manufactured by Shimadzu Corporation).

In addition, the ink receiving layer is preferably excellent in transparency, as a guide, the haze value when the ink receiving layer is formed on a transparent film support is preferably 30% or less, More preferably, it is 20% or less.
The haze value can be measured using a haze meter (HGM-2DP: Suga Test Instruments Co., Ltd.).

  A polymer fine particle dispersion may be added to a constituent layer (for example, an ink receiving layer or a back layer) of the ink jet recording material of the present invention. This polymer fine particle dispersion is used for the purpose of improving film properties such as dimensional stabilization, curling prevention, adhesion prevention, and film cracking prevention. The polymer fine particle dispersion is described in JP-A-62-245258 and JP-A-10-228076. If a polymer fine particle dispersion having a low glass transition temperature (40 ° C. or lower) is added to the layer containing the mordant, cracking and curling of the layer can be prevented. Further, even when a polymer fine particle dispersion having a high glass transition temperature is added to the back layer, curling can be prevented.

  Ink jet recording materials of the present invention are disclosed in JP-A-10-81064, JP-A-10-119423, JP-A-10-157277, JP-A-10-217601, JP-A-11-348409, JP-A-2001-138621, 2000. No. 43401, No. 2000-21235, No. 2000-309157, No. 2001-96897, No. 2001-138627, JP-A-11-91242, No. 8-2087, No. 8-2090, No. 8- It can also be produced by the methods described in Japanese Patent Nos. 2091 and 8-2093.

  The ink jet recording material in the invention may further have an ink solvent absorbing layer, an intermediate layer, a protective layer and the like in addition to the ink receiving layer. Further, an undercoat layer may be provided on the support for the purpose of improving the adhesion between the ink receiving layer and the support and appropriately adjusting the electric resistance value.

  The ink receiving layer may be provided only on one side of the support, or may be provided on both sides of the support for the purpose of preventing deformation such as curling. When the ink receiving layer is provided only on one side of the support, the anti-reflection film may be provided on the opposite side surface or both sides for the purpose of increasing light transmission. .

  In addition, by applying boric acid or a boron compound to the surface of the support on the side where the ink receiving layer is provided, and forming an ink receiving layer thereon, the glossiness and surface smoothness of the ink receiving layer can be improved. In addition, it is possible to suppress aging blurring of an image after printing in a high temperature and high humidity environment.

≪Inkjet recording method≫
In the ink jet recording method of the present invention, the ink jet recording method is not limited, and a known method, for example, a charge control method for discharging ink using electrostatic attraction force, or a drop-on-demand method using vibration pressure of a piezoelectric element. Method (pressure pulse method), acoustic ink method that converts electrical signals into acoustic beams, irradiates ink, and discharges ink by using radiation pressure, and forms bubbles by heating ink and uses generated pressure Used for thermal ink jet system. Inkjet recording methods use a method of ejecting a large number of low-density inks called photo inks in a small volume, a method of improving image quality using a plurality of inks having substantially the same hue and different concentrations, and colorless and transparent inks. The method is included.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples. In the examples, “parts” and “%” represent “parts by mass” and “% by mass” unless otherwise specified.

[Example 1]
≪Preparation of inkjet recording material≫
<Production of polyolefin resin-coated paper>
A 1: 1 mixture of hardwood bleached kraft pulp (LBKP) and hardwood bleached sulfite pulp (LBSP) was beaten to 300 ml with Canadian Standard Freeness to prepare a pulp slurry. As a sizing agent, 0.5% by mass of alkyl ketene dimer with respect to pulp, 1.0% by mass of polyacrylamide with respect to pulp as a strengthening agent, 2.0% by mass of cationized starch with respect to pulp, and polyamide epichlorohydrin resin 0.5% by mass of pulp was added and diluted with water to give 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 polyolefin resin-coated paper base paper. A polyethylene resin composition in which 10% by mass of anatase-type titanium is uniformly dispersed with respect to 100% by mass of low-density polyethylene having a density of 0.918 g / cm ³ is melted at 320 ° C. at 320 ° C. Extrusion-coating so as to have a thickness of 35 μm / min and extrusion-coating using a cooling roll having a finely roughened surface. On the other side, a blend resin composition of 70 parts by mass of a high density polyethylene resin having a density of 0.962 g / cm ³ and 30 parts by mass of a low density polyethylene resin having a density of 0.918 was similarly melted at 320 ° C. to obtain a thickness. Extrusion coating was carried out to a thickness of 30 μm, and extrusion coating was performed using a cooling roll having a rough surface.

The surface of the polyolefin resin-coated paper was subjected to a high-frequency corona discharge treatment, and then an undercoat layer having the following composition was applied and dried so that gelatin was 50 mg / m ² to prepare a support. In addition, a part represents the mass part of solid content.

(Composition of undercoat layer)
・ Lime-treated gelatin ・ ・ ・ 100 parts ・ Sulfosuccinic acid-2-ethylhexyl ester salt ・ ・ ・ 2 parts ・ Chrome alum ・ ・ ・ 10 parts

<Preparation of first coating liquid (coating liquid A) and overcoat coating liquid (coating liquid B)>
Ion exchange water was further added to the composition of the following first coating liquid (coating liquid A) to prepare a first coating liquid (coating liquid A) so that the concentration of the vapor phase silica was 9% by mass. The prepared first coating solution (coating solution A) had a pH of 4.0.
Further, ion exchange water is further added to the composition of the following overcoat coating solution (coating solution B) so that the concentration of the exemplified compound P-1 is 2% by mass. Prepared.

-Composition of the first coating solution (coating solution A)-
Gas phase method silica (average primary particle size 7 nm, specific surface area 300 m ² / g by BET method) ... 100 parts dimethyl diallyl ammonium chloride homopolymer (Daiichi Kogyo Seiyaku Co., Ltd., Charol DC902P, molecular weight 9000)・ ・ ・ 4 parts ・ Boric acid ・ ・ ・ 3 parts ・ Polyvinyl alcohol (saponification degree 88%, average polymerization degree 3500) ・ ・ ・ 22 parts ・ Basic polyaluminum hydroxide (trade name: Alphain 83, Daimei Chemical Industries) (Made by Co., Ltd.)
・ ・ ・ 8 parts ・ Surfactant (Betaine; manufactured by Nippon Surfactant, Swanol AM) ・ ・ ・ 0.3 part

-Composition of overcoat coating solution (coating solution B)-
Exemplified compound P-1: 1 part Surfactant (polyoxyethylene oleyl ether, “Emulgen 109P” manufactured by Kao Corporation): 0.6 part

<Formation of ink receiving layer>
(Formation of coating layer)
The prepared first coating solution (coating solution A) is applied to the surface provided with the undercoat layer of the support obtained in <Preparation of polyolefin resin-coated paper> by a slide bead coater. A layer (porous membrane) was formed. The moisture coating amount of the first coating liquid (coating liquid A) at this time was 200 g / m ² (the solid content coating amount of the vapor phase method silica was 18 g / m ² ).

(Drying the coating layer)
The obtained coating layer is cooled for 20 seconds in a cooling zone maintained at 0 ° C., and then dried with a hot air dryer at 80 ° C. (wind speed 3 to 8 / second) until the solid content concentration of the coating layer reaches 20%. I let you. The coating layer showed constant rate drying at this time, but switched from constant rate drying to reduced rate drying when 3 minutes had elapsed from the application of the first coating solution (coating solution A). Confirmation of switching was performed by confirming that the film surface temperature was 50 ° C. or higher.

(Application of overcoat coating solution (coating solution B))
The overcoat coating solution (coating solution B) prepared above was overcoated (coated) using an automatic coating machine (manufactured by TECHNO SUPPLY Co.) so that the moisture coating amount was 20 g / m ² .
Further, the ink receiving layer was obtained by drying at 80 ° C. for 10 minutes.
Thus, an ink jet recording material (ink jet recording sheet) having a configuration in which an ink receiving layer was formed on a support was obtained.

≪Evaluation≫
<Surface shape>
The surface state of the ink receiving layer of the ink jet recording material produced above was visually evaluated. Judgment was made according to the following criteria.
~ Criteria ~
○: No crack was observed.
(Triangle | delta): Although the micro crack was observed, it was in the allowable range practically.
X: Remarkable cracks were observed and exceeded the practically acceptable range.

<Bronze phenomenon>
About the inkjet recording material produced above, Y (yellow), M (magenta), C (cyan), K (black), B (by the inkjet printer (trade name: PMG-800, manufactured by Seiko Epson Corporation)) Solid printing was performed with inks of blue), G (green), and R (red), and the presence or absence of bronzing was evaluated visually. Judgment was made according to the following criteria.
~ Criteria ~
○: Bronze phenomenon did not occur.
Δ: Bronze phenomenon occurred slightly, but was practically acceptable.
X: The bronze phenomenon occurred remarkably and exceeded the practically acceptable range.

<Ozone resistance evaluation method>
As an evaluation of the storage stability of the recorded image, the ozone resistance was evaluated as follows.
Using an inkjet printer ("PMG-800" manufactured by Epson Corporation) loaded with a genuine ink set, magenta solid images were printed on each recording medium, respectively, at 23 ° C, 60% RH, and ozone concentration of 10 ppm. The samples were stored for 48 hours in the atmosphere. Ozone resistance was evaluated according to the following criteria based on the residual ratio of cyan concentration before and after storage.
~ Criteria ~
A: 75% or more B: 55-75%
C: 55% or less

<Glossiness evaluation method>
A solid black image was printed on each inkjet recording medium using an inkjet printer (“PM-G800” manufactured by Seiko Epson Corporation). Thereafter, the glossiness of the black solid image portion was measured at an incident angle of 60 degrees and a received light intensity of 60 degrees using a digital variable angle glossimeter (Suga Test Instruments Co., Ltd. UGV-5D measuring hole 8 mm). Judgment was made according to the following criteria.
~ Criteria ~
A: 50% or more B: 35-50%
C: 35% or less

<Evaluation method for yellowing>
As an evaluation of the storage stability of the recorded image, yellowing was evaluated as follows.
A 2% aqueous solution of vanillin contained in cardboard or the like was prepared, and 1 ml was dropped on the ink receiving layer of each ink jet recording sheet, and the yellow density in the dropping portion after standing for 24 hours was visually observed. Yellowing was evaluated according to the following criteria.
~ Criteria ~
○: No yellowing was observed.
(Triangle | delta): Although slight yellow coloring was observed, it was in the acceptable range practically.
X: Remarkable yellow coloration was observed and exceeded the practically acceptable range.

[Example 2]
In Example 1, except that Exemplified Compound P-1 in the first coating liquid (Coating Liquid A) was changed to Exemplified Compound P-12, an inkjet recording material was produced in the same manner as in Example 1, and Example Evaluation similar to 1 was performed. The evaluation results are shown in Table 2.

Example 3
In Example 1, an ink jet recording material was produced in the same manner as in Example 1 except that the overcoat coating solution (coating solution B) was changed to the following composition and the concentration of colloidal silica was 5% by mass. Then, the same evaluation as in Example 1 was performed. The evaluation results are shown in Table 2.

-Overcoat coating solution (Coating solution B)-
Colloidal silica (anionic spherical colloidal silica; Snowtex ST-OL40 manufactured by Nissan Chemical Industries, Ltd., average primary particle size 40-50 nm) 100 parts Polyvinyl alcohol (degree of saponification 88%, average) Degree of polymerization 3500) ... 4 parts · Exemplified compound P-1 · 2 parts · Surfactant (betaine type; manufactured by Nippon Surfactant, Swanol AM)
... 0.3 parts

[Comparative Example 1]
The following 1st coating liquid (coating liquid A) is made into the moisture coating amount 200g / m < ² > (The solid content coating amount of a vapor-phase-method silica is 18 g / m < ² >), and solid content density | concentration will be 20% at 80 degreeC. Dried. Immediately after that, that is, before showing the rate-decreasing drying, it is immersed in a second coating liquid (coating liquid B) having the following composition for 30 seconds to deposit 20 g / m ² on the general coating layer, and further at 80 ° C. An ink jet recording material was prepared by drying for 10 minutes. Furthermore, the same evaluation as in Example 1 was performed. The evaluation results are shown in Table 2.

-First coating liquid (Coating liquid A)-
・ Gas phase method silica (average primary particle size 7 nm, specific surface area 300 m ² / g by BET method)
10 parts dimethyl diallyl ammonium chloride homopolymer (Daiichi Kogyo Seiyaku Co., Ltd., Charol DC902P, molecular weight 9000, 51.5%) 1.0 parts boric acid 0.4 parts Polyvinyl alcohol (saponification degree 98.5%, average polymerization degree 2400)
・ ・ ・ 2.2 parts ・ Surfactant (Polyoxyethylene oleyl ether (10% aqueous solution of “Emulgen 109P” manufactured by Kao Corporation)) ・ ・ ・ 33.0 parts

-Composition of the second coating liquid (coating liquid B)-
・ Boric acid (crosslinking agent, 100%) ・ ・ ・ 6.5 parts ・ Basic chemicals (mordant, “PAA-03” manufactured by Nitto Boseki Co., Ltd., 20% aqueous solution) ・ 125 parts ・ Ion-exchanged water ・720 parts Surface pH adjuster (ammonium chloride, 100%) ... 8.0 parts Surfactant ("Emulgen 109P" manufactured by Kao Corporation, 2%) ... 100.0 parts Surfactant (Fluorine surfactant (10% aqueous solution of “Megafac F-1405” manufactured by Dainippon Ink & Chemicals, Inc.) 20.0 parts, Exemplified compound P-1 2.0 parts

[Comparative Example 2]
In Example 1, an inkjet recording material was produced in the same manner as in Example 1 except that the overcoat coating solution was not applied, and the same evaluation as in Example 1 was performed. The evaluation results are shown in Table 2.

[Comparative Example 3]
Inkjet recording was carried out in the same manner as in Example 1 except that no overcoat coating solution was applied and 0.4 part of Exemplified Compound P-1 was added to the first coating solution (Coating Solution A). Materials were prepared and evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

As shown in Table 2, after the coating layer formed by coating the coating liquid A showed reduction drying, coating liquid B containing a specific compound was coated (overcoat) to form an ink receiving layer. The ink jet recording material was suppressed in bronzing and yellowing, and had good ozone resistance and surface condition (Examples 1 to 3).
On the other hand, in the ink jet recording material in which the ink receiving layer is formed by applying the coating liquid B containing the specific compound before the coating layer formed by applying the coating liquid A shows the reduction rate drying, Although the ozone resistance was good, the surface condition and yellowing deteriorated (Comparative Example 1).
Further, in the ink jet recording material in which the specific compound was added to the coating solution A, the coating solution A was so thickened that the coating solution A could not be applied (Comparative Example 3).
Furthermore, the bronzing phenomenon deteriorated in the ink jet recording material in which the ink receiving layer was formed only with the coating liquid A and the specific compound was not added (Comparative Example 2).

  As described above, the examples using the exemplary compounds P-1 and P-12 as the substantially colorless compounds having 10 or more atoms having conjugated π electrons in one molecule have been described. Even when other compounds included in the scope of the present invention are used, the same compounds can be obtained.

Claims (7)

  An ink jet recording material having an ink receiving layer on a support, wherein the ink receiving layer forms a coating layer using at least a coating liquid A containing fine particles and a water-soluble resin, and the formed coating layer comprises It is formed by applying a coating liquid B containing a substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule on the coating layer after showing reduced-rate drying. An inkjet recording material.   The inkjet recording material according to claim 1, wherein the coating liquid B further contains colloidal silica.   The inkjet recording material according to claim 1, wherein the coating liquid B does not contain a cationic compound.   The substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule has at least two aromatic ring groups (including aromatic heterocyclic groups). The inkjet recording material of any one of -3.   The substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule is a compound having no fluorescence, the wavelength of the absorption peak on the longest wave side (λmax) is 350 nm or less, and 400 to 400 The ink jet recording material according to any one of claims 1 to 4, wherein the molar extinction coefficient at any wavelength in the visible spectral region of 700 nm is a compound having a molecular weight of 10,000 or less.   The inkjet recording material according to claim 1, wherein the substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule has a solubilizing group. .   A method for producing an ink jet recording material having an ink receiving layer on a support, wherein the ink receiving layer forms a coating layer on the support using at least a coating liquid A containing fine particles and a water-soluble resin, After the formed coating layer shows reduced-rate drying, a coating solution B containing a substantially colorless compound having 10 or more atoms having conjugated π electrons in one molecule is coated on the coating layer. A method for producing an ink jet recording material, comprising: forming an ink jet recording material.