JP2005246638A - Image recording material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image recording material which shows excellent flatness, high quality-image formation, especially, high glossiness, further, favorable ink absorption in case an ink acceptance layer is formed, and can effectively inhibit the generation of a blur of an image formed over time. <P>SOLUTION: This image recording material has at least a coloring material acceptance layer formed on a support and also at least one layer containing an ultrafine particle inorganic compound with an index of refraction of not less than 1.9 and an average particle diameter of not more than 100 nm, formed between the support and the coloring material acceptance layer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image recording material including an ink jet recording medium having an ink receiving layer and a digital recording medium having a toner receiving layer.

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

In addition, with the recent increase in resolution of inkjet printers and the development of hardware (devices), various types of inkjet recording media have been developed, and in recent years it has become possible to obtain so-called photographic-like high-quality recorded matter. .
In particular, the characteristics required for ink jet recording media generally include (1) fast drying (high ink absorption speed), and (2) proper and uniform ink dot diameter (similar to (3) Good granularity, (4) High dot roundness, (5) High color density, (6) High saturation (no blurring) (7) The light resistance, gas resistance and water resistance of the printed part are good, (8) the whiteness of the recording surface is high, and (9) the preservability of the recording medium is good (yellow during long-term storage). No discoloration, image does not bleed after long-term storage), (10) good deformation and good dimensional stability (curl is sufficiently small), and (11) good hard running performance. Etc. In addition to the above properties, glossy paper, surface smoothness, and photographic paper-like texture similar to silver salt photography are also required for photo glossy paper used for the purpose of obtaining so-called photo-like high-quality recorded material. Is done.

  For example, there is an ink jet recording sheet that includes fine inorganic pigment particles and a water-soluble resin and has a porous colorant receiving layer having a high porosity provided on a support (for example, Patent Documents 1 and 2). reference). These recording sheets, particularly ink jet recording sheets provided with a colorant-receiving layer having a porous structure using silica as inorganic pigment fine particles, are excellent in ink absorbability depending on the configuration, and form high-resolution images. It is said that it has a high ink receiving performance and also exhibits a high gloss.

  Conventionally, resin-coated paper in which both sides of a paper substrate are laminated with polyethylene resin has been generally used as a support constituting an inkjet recording medium in order to provide high-quality characteristics with glossiness and flatness. It was. However, since this resin-coated paper does not absorb the ink solvent in the applied ink, when it is stored in a file immediately after printing, the image does not evaporate and is left behind due to the remaining ink solvent. There is a problem of bleeding.

  In order to prevent bleeding of an image, it is also conceivable to form an ink jet recording medium using a support having no resin film. However, if the ink receiving layer is provided as it is on an absorbent support such as a paper substrate that is currently distributed, the aging blur is reduced by the absorption of the ink solvent, but the surface glossiness is remarkably lowered. End up.

  On the other hand, using a resin-coated paper having a resin layer, a halogenation in which a layer containing at least a water-soluble polymer centered on gelatin and ultrafine titanium dioxide is provided between the support and the photosensitive silver halide emulsion Silver photographic materials have been proposed (see, for example, Patent Document 3). Such a silver halide photographic light-sensitive material is intended to improve resolution and luminance and to improve light resistance. However, such a silver halide photographic light-sensitive material is assumed to contain gelatin as a water-soluble resin, and there is no viewpoint of preventing the above-mentioned aging blur.

JP 10-119423 A Japanese Patent Laid-Open No. 10-217601 JP-A-2003-43631

  The present invention has been made in view of the above, has excellent flatness, can form a high-quality image, has a particularly high glossiness, and has a good ink when an ink receiving layer is provided. It is an object of the present invention to provide an image recording material which has an absorptivity and can effectively suppress the occurrence of aging blur in formed images.

The above problem is solved by the following means.
<1> An image recording material having at least a color material receiving layer on a support, wherein the refractive index is 1.9 or more and an average particle diameter is between the support and the color material receiving layer. An image recording material comprising at least one layer containing an ultrafine inorganic compound having a size of 100 nm or less.

  <2> The image recording material according to <1>, wherein the ultrafine inorganic compound is at least one selected from titanium dioxide and zirconia.

  <3> The image recording material according to <1> or <2>, wherein a content of the ultrafine inorganic compound in the layer containing the ultrafine inorganic compound is 5 to 95% by mass.

  <4> The image recording material according to <1> to <3>, wherein the support is a paper substrate, and the layer containing the ultrafine inorganic compound contains a thermoplastic resin. is there.

<5> The image recording material according to <4>, wherein the coating amount of the layer containing the ultrafine inorganic compound is ² to 30 g / m2.

  <6> The thermoplastic resin is acrylic latex, acrylic silicone latex, acrylic epoxy latex, acrylic styrene latex, acrylic urethane latex, styrene-butadiene latex, acrylonitrile-butadiene latex, and vinyl acetate latex. <4> or <5>, wherein the image recording material is at least one selected from the above.

  <7> The image recording according to the above <4> to <6>, wherein the thermoplastic resin has a glass transition temperature of 5 to 70 ° C. and a minimum film forming temperature of 5 to 60 ° C. Material.

  <8> After the layer containing the ultrafine inorganic compound is formed on the paper base material, the surface temperature of the metal roll is set to the thermoplastic resin by using a calendar in which at least one of the roll pair is composed of a metal roll. The image recording material according to the above <4> to <7>, wherein the image recording material is calendered at a temperature of not less than the glass transition temperature and a nip pressure of the roll pair of 50 to 400 kg / cm.

  <9> The support is a resin-coated paper having a resin layer on the side where at least the layer containing the ultrafine inorganic compound is provided, and the layer containing the ultrafine inorganic compound contains a water-soluble resin <1> to <3>, wherein the image recording material is characterized in that

The coating amount of the layer containing the <10> the ultrafine inorganic compound is an image recording material of the <9>, which is a 0.05 to 20 g / m ^2.

  <11> The water-soluble resin is at least one selected from a polyvinyl alcohol resin, a cellulose resin, a resin having an ether bond, a resin having a carbamoyl group, a resin having a carboxyl group, and gelatins. <9> or <10> The image recording material.

  <12> The image recording material according to <1> to <11>, wherein the color material receiving layer is an ink receiving layer.

  <13> The image recording material according to <12>, wherein the ink receiving layer includes a water-soluble resin, a crosslinking agent capable of crosslinking the water-soluble resin, fine particles, and a mordant.

  <14> The ink-receiving layer is at least selected from a polyvinyl alcohol resin, a cellulose resin, a resin having an ether bond, a resin having a carbamoyl group, a resin having a carboxyl group, and gelatins as the water-soluble resin. The image recording material according to <13>, wherein the image recording material comprises at least one selected from silica fine particles, colloidal silica, alumina fine particles, and pseudoboehmite as the fine particles.

  <15> The ink receiving layer is a layer obtained by crosslinking and curing a coating layer coated with a coating solution containing at least the fine particles and the water-soluble resin, and the crosslinking and curing is performed using the coating solution and / or the following base. And (1) at the same time when the coating solution is applied to form a coating layer, or (2) during the drying of the coating layer formed by coating the coating solution. <13> or <14> above, wherein the coating layer is applied by applying a basic solution having a pH of 7.1 or higher to the coating layer at any time before the coating layer exhibits reduced drying. It is an image recording material.

  According to the present invention, it is possible to form a high-quality image with excellent flatness, particularly high glossiness, and when having an ink receiving layer, it has good ink absorbency, and It is possible to provide an image recording material capable of effectively suppressing the occurrence of aging blur in the formed image.

<Image recording material>
The image recording material of the present invention is an image recording material having at least a color material receiving layer on a support, and the refractive index is 1.9 or more between the support and the color material receiving layer. And it has at least one layer containing the ultrafine particle inorganic compound whose average particle diameter is 100 nm or less.

  According to the image recording material of the present invention, since a layer containing an ultrafine inorganic compound (hereinafter sometimes referred to as “ultrafine particle-containing layer”) is provided between the colorant receiving layer and the support, the planarity is improved. An excellent and high-quality image can be formed, and the glossiness is high. Here, the color material receiving layer means a layer that receives a color material such as ink or toner. The color material receiving layer is formed for the purpose of receiving ink containing a color material, mordant, UV absorber, thermoplastic resin particles for providing gloss, and the like and having no color material. In some cases, the ink receiving layer becomes an image recording material having the ink receiving layer, for example, an ink jet recording medium used in an ink jet recording method. Further, when the color material receiving layer is formed for the purpose of receiving toner, it becomes a toner receiving layer, and the image recording material having this is referred to as a digital recording medium used for electrophotography, for example. Is done.

<Ultrafine particle-containing layer>
The ultrafine particle-containing layer in the present invention comprises at least an ultrafine inorganic compound having a refractive index of 1.9 or more and an average particle diameter of 100 nm or less. The ultrafine particle-containing layer is provided at least between the colorant receiving layer and the support.
The ultrafine particle-containing layer in the present invention preferably contains a thermoplastic resin as a binder when a paper substrate is used as a support. On the other hand, when a resin-coated paper having a resin layer as a support is used, it is preferable to contain a water-soluble resin as a binder. In this case, the ultrafine particle-containing layer is formed on the side of the support on which the resin layer is provided.

  Here, examples of the “ultrafine inorganic compound having a refractive index of 1.9 or more and an average particle diameter of 100 nm or less” include rutile titanium dioxide, anatase titanium dioxide, zirconia, zinc oxide, zinc sulfide, and the like. In particular, titanium dioxide (ultrafine particle titanium dioxide) such as rutile type titanium dioxide and anatase type titanium dioxide and zirconia (ultrafine particle zirconia) are preferable. Further, the refractive index of the ultrafine inorganic compound is preferably 2.0 or more, and the upper limit thereof is preferably 3.0 or less. The average particle size of the ultrafine inorganic compound is preferably 80 nm or less, and more preferably 60 nm or less. The lower limit of the average particle diameter of the ultrafine inorganic compound is not particularly limited, but is preferably 5 nm or more. Here, the “average particle diameter” means an area average particle diameter, and is calculated from the number average by regarding the diameter of the particle as a circle equivalent to the projected area of each particle.

The coating amount of the ultrafine inorganic compound in the ultrafine particle-containing layer in the present invention is preferably 0.1 to ² g / m ² from the viewpoint of enhancing ink absorbency, and is preferably 0.5 to 1.5 g / m ^2. it is more preferably m ^2.

  Furthermore, the content of the ultrafine inorganic compound in the ultrafine particle-containing layer is 5 to 95% by mass from the viewpoint of increasing the film strength, preventing film breakage, powder falling, and the like, and further increasing the ink absorbability. Preferably, it is 15-40 mass%.

-Ultrafine titanium dioxide-
As described above, the ultrafine inorganic compound is preferably ultrafine titanium dioxide. In this specification, “ultrafine particle titanium dioxide” means titanium dioxide having an average particle diameter of 100 nm or less. That is, the ultrafine particle titanium dioxide is an ultrafine particle whose primary particle diameter is one or more orders of magnitude smaller than the conventional pigment called “titanium white”. For this reason, light scattering is suppressed, transparency is high, and an ultraviolet-absorbing ability is also significantly high. Hereinafter, ultrafine titanium dioxide may be simply referred to as “titanium dioxide”.

  The average particle diameter of the titanium dioxide is preferably 20 nm or less, more preferably 15 nm or less, and particularly preferably 10 nm or less from the viewpoints of improving the gloss of the coated surface and increasing the ink absorbability. Here, the “average particle diameter” means the area average particle diameter as described above, and is calculated from the number average of the diameters of the particles with a circle equivalent to the projected area of each particle. It is. The particle size distribution of the titanium dioxide is monodispersed with a coefficient of variation (the standard deviation of the particle size distribution divided by the average particle size) of 20% or less, preferably 15% or less, more preferably 10% or less. It is preferable that

  The titanium dioxide can be produced by subjecting a titanium salt to a treatment such as hydrolysis or gas phase oxidation. The titanium dioxide may have any crystal structure of rutile type, brookite type, and anatase type, but the rutile type is particularly preferable from the viewpoint of reflectance of visible light.

The coating amount of the titanium dioxide in the ultrafine particle-containing layer in the present invention, in view of enhancing the ink absorbability is preferably ^{0.1~2g / m 2, 0.5~1.5g / m} 2 More preferably.

  Furthermore, the content of titanium dioxide in the ultrafine particle-containing layer is preferably 5 to 95% by mass from the viewpoint of increasing the film strength, preventing film cracking and powder falling, and further increasing the ink absorbency. More preferably, it is 15-40 mass%.

  Further, the titanium dioxide may be subjected to surface treatment with an inorganic compound or an organic compound in order to improve dispersibility and workability. Examples of the surface treatment include those disclosed in JP-A Nos. 52-35625, 55-10865, 57-35855, 62-25553, 62-103635, and JP-A-9-050093. What and methods can be used. For the surface treatment, an inorganic compound such as aluminum oxide hydrate, hydrous zinc oxide, or silicon dioxide, or an organic compound such as divalent to tetravalent alcohol, trimethylolamine, titanate coupling agent or silane coupling agent is used. It can be preferably used as a treating agent. The amount of these surface treatment agents used can be selected according to the purpose. For example, in the case of the above-mentioned inorganic surface treatment agent, the range of about 3% by mass or less is common with respect to ultrafine titanium dioxide, and the range of 0.01 to 1% by mass is preferable. Moreover, in the case of the said organic compound, the range of about 5 mass% or less is common, and the range of 0.1-3 mass% is preferable.

-Ultrafine zirconia-
Moreover, as the ultrafine inorganic compound, ultrafine zirconia is also preferable. In this specification, “ultrafine particle zirconia” means zirconia having an average particle diameter of 100 nm or less. Here, “zirconia” means an oxide of zirconium whose composition formula is ZrO ₂ . Hereinafter, the ultrafine particle zirconia may be simply referred to as “zirconia”.

  The average particle size of the zirconia is 100 nm or less, and preferably 80 nm or less, from the viewpoint of suppressing haze to improve image quality and increasing ink absorbability. Here, the “average particle diameter” means the area average particle diameter as described above, and is calculated from the number average of the diameters of the particles with a circle equivalent to the projected area of each particle. It is.

  As said zirconia, what formed the deposit in the liquid mixture of a zirconia propoxide, water, and nitric acid, and peptized this nitric acid with a nitric acid (peptization) etc. can be used. As the zirconia, acidic zirconia described in US Pat. No. 2,984,628, Japanese Patent Laid-Open No. 58-79818, and basic zirconia described in Japanese Patent Laid-Open No. 8-277115 are used. be able to. Moreover, as said zirconia, commercially available NTS-30A, NZS-30B, NZS-20A (Nissan Chemical Co., Ltd. product) etc. can be used, for example.

The coating amount of the zirconia in the ultrafine particle-containing layer in the present invention is preferably 0.1 to ² g / m ² from the viewpoint of enhancing ink absorbency, similar to the titanium dioxide, and preferably 0.5 to More preferably, it is 1.5 g / m ² .

  Further, the content of zirconia in the ultrafine particle-containing layer is preferably 5 to 95% by mass from the viewpoint of increasing the film strength, preventing film cracking, powder falling, and the like, and further increasing ink absorbency. More preferably, it is -40 mass%.

  In addition, within the range that does not impair the effects of the invention, the ultrafine particle-containing layer in the present invention includes the above-mentioned ultrafine titanium dioxide and ultrafine particle zirconia, as well as the following white pigments such as ordinary titanium dioxide, aluminum oxide, zinc oxide, and carbonic acid. You may contain or disperse light reflective substances, such as calcium and a calcium sulfate, or pigment substances. The above ultrafine titanium dioxide is a relatively expensive material due to its special manufacturing method, and it is economically advantageous to use a pigment having another normal particle size as long as the desired quality can be secured. Become. When the ultrafine inorganic compound in the present invention such as the ultrafine titanium dioxide or ultrafine zirconia is used in combination with another pigment, the amount of the ultrafine inorganic compound used is preferably 30% by mass or more of the total pigment. And more preferably 50% by mass or more.

-White pigment-
As described above, the ultrafine particle-containing layer may use a white pigment in combination with titanium dioxide. Examples of the white pigment include titanium oxide, barium sulfate, barium carbonate, calcium carbonate, lithopone, alumina white, zinc oxide, silica antimony trioxide, and titanium phosphate. These can be used individually by 1 type or in mixture of 2 or more types. Of these, titanium oxide is particularly preferable in terms of whiteness, dispersibility, and stability.

  The particle size of the white pigment is preferably 0.1 to 0.5 μm. When the particle size of the white pigment is in the range of 0.1 to 5 μm, the whiteness and gloss can be effectively improved.

  The titanium oxide may be a rutile or anatase type, and these may be used alone or in combination. Further, the titanium oxide may be either one produced by the sulfuric acid method or one produced by the chlorine method. Examples of the titanium oxide include hydrous alumina treatment, hydrous silicon dioxide treatment, or surface coating treatment with an inorganic substance such as zinc oxide treatment, trimethylolmethane, trimethylolethane, trimethylolpropane, and 2,4-dihydroxy-2. -It can select suitably from what carried out surface coating processing by organic substances, such as methylpentane, or siloxane processing, such as polydimethylsiloxane.

  The refractive index of the white pigment is preferably 1.5 or more, and more preferably 2.0 or more. When a white pigment having a refractive index in this range is included, a high-quality image can be formed.

Furthermore, the specific surface area of the white pigment by the BET method is preferably less than 100 m ² / g. When the critical area by the BET method of the white pigment is less than 100 m ² / g, it is possible to suppress the penetration of the coating liquid when the color material receiving layer is formed by coating.
Here, the “BET method” is one of powder surface area measurement methods by a gas phase adsorption method, and is a method for obtaining the total surface area, that is, the specific surface area of a 1 g sample from the adsorption isotherm. Usually, nitrogen gas is used as the adsorbed gas, and a method of measuring the amount of adsorption from the change in pressure or volume of the gas to be adsorbed is common. Prominent expressions representing the isotherm of multimolecular adsorption include Brunauer Emmett and Teller's equation (BET equation). Based on this, the amount of adsorption is obtained, and the surface area is calculated by multiplying the area occupied by one adsorbed molecule on the surface. be able to.

The content of the white pigment in the ultrafine particle-containing layer varies depending on the type of white pigment, the type of thermoplastic resin, the layer thickness, etc., but for the thermoplastic resin contained in the ultrafine particle-containing layer, for example, Usually, 50-200 mass% is preferable.
In addition, well-known additives, such as antioxidant, can also be added to the said ultrafine particle content layer.

-Thermoplastic resin-
As described above, the image recording material of the present invention is a binder for the ultrafine particle-containing layer from the viewpoint of preventing the coating liquid from penetrating when the colorant receiving layer is applied and formed when the paper base material described later is used as the support. It is preferable to use a thermoplastic resin. When an ink-receiving layer is provided on an image recording material having such a structure and used as an ink-jet recording medium, the ultrafine particle-containing layer containing the thermoplastic resin exhibits high ink solvent permeability. The solvent can be absorbed by the paper base material as the support, and the occurrence of aging blur can be effectively suppressed.

  There is no restriction | limiting in particular as said thermoplastic resin, From what made the microparticles | fine-particles of well-known thermoplastic resins, such as polyolefin resin (For example, the homopolymer of alpha olefins, such as polyethylene and a polypropylene, or these mixtures), or its latex. It can be appropriately selected and used. Among these, as the thermoplastic resin, latex is preferable, and acrylic latex, acrylic silicone latex, acrylic epoxy latex, acrylic styrene latex, acrylic urethane latex, styrene-butadiene latex, acrylonitrile-butadiene latex, and Preferred examples include vinyl acetate latex, and it is preferable to use at least one selected from these.

Specific examples of the thermoplastic resin include hybrid emulsion Aquabrid series (for example, Aquabrid 903, Asi-86, Asi-91, 4635, 4901, and the like manufactured by Daicel Chemical Industries, Ltd.) MSi-04S, AU-124, AU-131, AEA-61, AEC-69, AEC-162, etc.).
In addition, said thermoplastic resin can also use together 2 or more types not only individually by 1 type.

  The glass transition temperature (Tg) of the thermoplastic resin is preferably 5 to 70 ° C, particularly preferably 15 to 70 ° C. When the Tg is in the range of 5 to 70 ° C., the ultrafine particle-containing layer forming liquid (coating liquid and the like) is excellent in handling in production without causing problems such as burrs. Furthermore, since it is not necessary to set the calendar temperature high, it is easy to obtain a desired gloss, and adhesion to the surface of the metal roll is unlikely to occur.

  Moreover, as minimum film-forming temperature of the said thermoplastic resin, 5-60 degreeC is preferable and 15-60 degreeC is still more preferable. When a thermoplastic resin having a minimum film formation temperature of 5 to 60 ° C. is used, the handling in manufacturing is excellent without causing problems such as burrs of the liquid for forming an ultrafine particle layer (coating liquid and the like). Further, it is possible to suppress permeation when an ink receiving layer described later is formed, and to form a layer having a microporosity sufficient to quickly permeate the ink solvent without lowering the coating surface state of the layer. be able to.

  As content of the said thermoplastic resin in the said ultrafine particle content layer, 15-95 mass% is preferable with respect to solid content in the said ultrafine particle content layer, and 30-90 mass% is still more preferable. When the content is in the range of 30 to 90% by mass, the permeability of the ink solvent can be obtained without impairing the gloss and flatness after the calendering process described later, and the occurrence of blurring with time It can be effectively prevented.

  The ultrafine particle-containing layer containing the thermoplastic resin is formed using a dispersion solution. For example, (1) Ultrafine titanium dioxide is further dispersed while the thermoplastic resin is dispersed in a desired solvent. Or (2) a dispersion prepared by mixing, for example, a dispersion in which a thermoplastic resin is dispersed and a dispersion in which ultrafine titanium dioxide is dispersed. It can be formed by coating on a paper substrate by a known method such as coating.

When the ultrafine particle-containing layer containing the thermoplastic resin is formed by coating, for example, according to the above (2), a latex dispersion in which the thermoplastic resin is previously dispersed in water and a pigment dispersion in which ultrafine titanium dioxide is dispersed in water. A coating solution for forming an ultrafine particle-containing layer (hereinafter sometimes referred to as “coating solution for undercoat layer”) prepared by mixing and stirring (along with other components as necessary) and homogenizing them. To prepare. In the case of the above (1), one of the thermoplastic resin and the ultrafine titanium dioxide is dispersed in water, and the other (along with other components if necessary) is added and further dispersed and homogenized. The prepared coating solution for the undercoat layer is prepared, and the dry coating amount is, for example, ² to 30 g / m ² by a known coating method on the paper substrate (optionally via another layer). Thus, it can form suitably by making it apply | coat and drying.

  In addition to the coating method, the ultrafine particle-containing layer can be provided by immersing the paper substrate in an undercoat layer coating solution or by spraying the undercoat layer coating solution onto the paper substrate.

As a preferred embodiment, the ultrafine particle-containing layer containing the thermoplastic resin particles is preferably formed so that the dry coating amount is ² to 30 g / m ² . The dry coating amount is more preferably 4 to ²⁰ g / m2. When the dry coating amount is in the range of ^{2 to} 30 g / m ² , the penetration of the coating liquid for forming the colorant-receiving layer coated on the ultrafine particle-containing layer is suppressed, and sufficient A gloss imparting effect can be exhibited. In addition, since uneven coating is unlikely to occur, the coated surface of the color material receiving layer is excellent, and when the color material receiving layer is an ink receiving layer, the permeability of the ink solvent is high and effective An inhibitory effect can be exhibited.

  The application of the coating solution for the ultrafine particle-containing layer can be more suitably performed by a known coating method such as a blade coating method, a bar coating method, or a spray coating method. In addition, it is preferable that the solid content concentration of the coating liquid for support is in the range of 15 to 65% by mass.

  The layer thickness of the ultrafine particle-containing layer containing the thermoplastic resin particles is preferably 0.2 to 5.0 μm, and more preferably 0.5 to 3.0 μm. When the film thickness of the undercoat layer is 0.2 to 5.0 μm, when a calendar process described later is performed, the glossiness of the surface is high, and when the ink receiving layer is used as the colorant receiving layer, It is also possible to effectively prevent aging blurring that is likely to occur when a file is stored immediately after printing due to rapid penetration of the ink solvent.

-Calendar processing-
When a glossy undercoat layer containing the thermoplastic resin is formed on a paper substrate, after forming the ultrafine particle-containing layer, at least one of the roll pair is composed of a metal roll (preferably a metal roll and a resin roll). The surface temperature of the metal roll is set to be equal to or higher than the glass transition temperature of the thermoplastic resin, and the nip pressure of the roll pair is set to 50 to 400 kg using a calender (soft calender and / or super calender). It is preferable to perform a calendar treatment as / cm.

  Thus, after providing the ultrafine particle-containing layer on the paper substrate, by applying a calendar treatment under specific conditions, high gloss on the surface of the colorant receiving layer formed through the ultrafine particle-containing layer, While ensuring high flatness and high image quality image formability, at the same time, when the colorant receiving layer is an ink receiving layer, the ink solvent absorbability in the ink applied to the ink receiving layer during printing is improved. It is possible to effectively suppress bleeding of the formed image over time (aging blur).

  As described above, at least one of the roll pair is composed of a metal roll (preferably composed of a metal roll and a resin roll), a super calender, or both, and the calendar treatment is performed using the metal. It is preferable that the surface temperature of the roll is set to be equal to or higher than the glass transition temperature of the thermoplastic resin described above, and the nip pressure between the roll nips in the roll pair is set to 50 to 400 kg / cm.

  Hereinafter, a soft calendar having a metal roll and a resin roll and a super calendar will be described in detail. The metal roll is a cylindrical or columnar roll having a smooth surface, and is appropriately selected from known metal rolls without being limited to the material and the like as long as it has a heating means inside. Can be used. Further, since the metal roll is in contact with the recording surface side, that is, the surface on the side where an ink receiving layer described later is formed, on both sides of the support during calendering, the surface roughness is preferably as smooth as possible. Specifically, the surface roughness is preferably 0.3 s or less, more preferably 0.2 s or less, in terms of the surface roughness specified by JIS B0601.

  The surface temperature during the treatment of the metal roll is generally preferably 70 to 250 ° C. when the raw paper is treated. On the other hand, when the paper substrate provided with the ultrafine particle-containing layer described above is treated, it is preferable that the glass transition temperature Tg or more of the thermoplastic resin contained in the ultrafine particle-containing layer is higher. More preferably, the temperature is Tg or more and + 40 ° C. or less.

As said resin roll, it can select suitably from the synthetic resin roll which consists of a polyurethane resin, a polyamide resin, etc., and the thing whose Joard D hardness is 60-90 is suitable.
Further, the nip pressure of the roll pair having the metal roll is appropriately 50 to 400 kg / cm, and preferably 100 to 300 kg / cm. In the case of processing by a soft calendar and / or a super calendar in which a pair of rolls configured as described above is arranged, it is desirable that the processing is performed about 1 to 4 times.

  As described above, by using a paper base material, which will be described later, as a support, when the image forming material of the present invention is an inkjet recording medium, the ink solvent in the applied ink can be absorbed. Ink solvent that remains without being vaporized immediately after printing by eliminating the deterioration of glossiness, flatness, and high-quality image forming properties due to the use of a paper base material, and simultaneously imparting solvent permeation ability to the layer It is possible to effectively avoid aging blur caused by the above.

-Water-soluble resin-
Next, a case where a resin-coated paper having a resin layer is used as the support in the present invention will be described. As described above, when the resin-coated paper is used as the support in the present invention, the ultrafine particle-containing layer preferably contains a water-soluble resin as a binder from the viewpoint of handleability and adhesion to the colorant receiving layer. .

  As the water-soluble resin contained in the ultrafine particle-containing layer in the invention, the same water-soluble resin as that used in the ink receiving layer described later can be used. As such a water-soluble resin, for example, a polyvinyl alcohol resin (polyvinyl alcohol (PVA), acetoacetyl-modified polyvinyl alcohol, cation-modified polyvinyl alcohol, anion-modified polyvinyl alcohol, which is a resin having a hydroxy group as a hydrophilic structural unit, 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 having an ether bond [polyethylene oxide (PEO) , Polypropylene 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. The water-soluble resin can be used alone or in combination of two or more.

Among these, as the water-soluble resin used for the ultrafine particle-containing layer in the present invention, polyvinyl alcohol is particularly preferable from the viewpoint of ensuring ink absorbability and providing adhesion to the colorant receiving layer.
As the polyvinyl alcohol, polyvinyl alcohol having a polymerization degree of 300 to 4000 is preferable, and polyvinyl alcohol having 500 to 2500 is more preferable. The saponification degree of the polyvinyl alcohol is preferably 70 to 99.5%, more preferably 80 to 99.5%.
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 2000-18801, JP 2001-213045, JP 2001-328345, JP 8 -324105, JP-A-11-348417, etc. That. Examples of the water-soluble resin other than the polyvinyl alcohol resin include compounds described in “0011” to “0014” of JP-A No. 11-165461.
Said water-soluble resin may be used independently and may use 2 or more types together.

  Among these, specific examples of the polyvinyl alcohol used in the ultrafine particle-containing layer include fully saponified polyvinyl alcohol, partially saponified polyvinyl alcohol, acetoacetyl-modified polyvinyl alcohol, cation-modified polyvinyl alcohol, anion-modified polyvinyl alcohol, and silanol-modified. Polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, aromatic amino group-modified polyvinyl alcohol, thiol group-modified polyvinyl alcohol, and ketone group-modified polyvinyl alcohol are preferred, and are the same type of polyvinyl alcohol used in the colorant receiving layer. More preferably.

  As content of the said water-soluble resin used for the ultrafine particle content layer in this invention, 15-95 mass% is preferable with respect to the total solid content mass of an ultrafine particle content layer from a viewpoint of preventing powder fall, 30 -90 mass% is still more preferable.

The ultrafine particle-containing layer containing the water-soluble resin is preferably formed so that the dry coating amount is 0.05 to 20 g / m ² . The dry coating amount is more preferably 4 to ²⁰ g / m2. When the dry coating amount is in the range of 0.05 to 20 / m ² , it suppresses the infiltration of the coating solution for forming the colorant receiving layer that is coated on the ultrafine particle-containing layer, A sufficient gloss imparting effect can be exhibited. In addition, since uneven coating is unlikely to occur, the coated surface of the color material receiving layer is excellent, and when the color material receiving layer is an ink receiving layer, the permeability of the ink solvent is high and effective An inhibitory effect can be exhibited. It should be noted that when an ultrafine particle-containing layer containing a water-soluble resin is provided on the resin coating, even if the coating amount is reduced, compared to the case where an ultrafine particle-containing layer containing a thermoplastic resin is provided on the paper base material. The effects of the invention can be sufficiently obtained.

  The application of the coating solution for the ultrafine particle-containing layer containing the water-soluble resin can be more suitably performed by a known coating method such as a blade coating method, a bar coating method, or a spray coating method. In addition, it is preferable that the solid content concentration of the coating liquid for support is in the range of 15 to 65% by mass.

  The layer thickness of the ultrafine particle-containing layer containing the water-soluble resin is preferably 0.2 to 10.0 m, and more preferably 1.0 to 5.0 μm. When the thickness of the undercoat layer is from 0.2 to 10.0 μm, it is possible to achieve both glossiness and ink solvent absorbability.

-Crosslinking agent-
The ultrafine particle-containing layer containing the water-soluble resin preferably includes a cross-linking agent that can cross-link the water-soluble resin, and is a layer formed by crosslinking and curing the water-soluble resin. The cross-linking agent used in the ultrafine particle-containing layer in the present invention can be appropriately selected depending on the type of water-soluble resin used in the ultrafine particle-containing layer. For example, the same cross-linking agent as used in the ink receiving layer described later is also used. be able to.

As such a crosslinking agent, boric acid or a boron compound is preferable in that the crosslinking reaction is rapid. Examples of the boron compound include borax, borate (for example, orthoborate, InBO ₃ , ScBO ₃ , YBO ₃ , LaBO ₃ , Mg ₃ (BO ₃ ) ₂ , Co ₃ (BO ₃ ) ₂ , diborate). (For example, Mg ₂ B ₂ O ₅ , Co ₂ B ₂ O ₅ ), metaborate (for example, LiBO ₂ , Ca (BO ₂ ) ₂ , NaBO ₂ , KBO ₂ ), tetraborate (for example, Na ₂ B ₄ O ₇ · 10H ₂ O), pentaborate (for example, KB ₅ O ₈ · 4H ₂ O, Ca ₂ B ₆ O ₁₁ · 7H ₂ O, CsB ₅ O ₅ ), and the like.

  Among these, borax, boric acid, and borate are preferable, boric acid is more preferable, and it is particularly preferable to use these in combination with polyvinyl alcohol, which is a water-soluble resin, in that a crosslinking reaction is rapidly caused.

  The content of the crosslinking agent in the ultrafine particle-containing layer containing the water-soluble resin is 0.01 to 0.5 parts by mass with respect to 1 part by mass of the water-soluble resin contained in the ultrafine particle-containing layer. It is more preferable that 0.05 to 0.1 part by mass is contained. When the content of the crosslinking agent is within the above range, the water-soluble resin can be crosslinked to effectively prevent cracking and the like.

  Further, as the crosslinking agent, boron and the following compounds other than boron compounds can also be used. Examples thereof include 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-triazine, active halogen compounds such as 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 methylol melamine); Epoxy Resin;

Isocyanate compounds such as 1,6-hexamethylene diisocyanate; Aziridine compounds described in US Pat. Nos. 3,017,280 and 2,983,611; 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 compounds such as dioxane; Titanium lactate, aluminum sulfate, chromium alum, potash alum, metal-containing compounds such as zirconyl acetate and chromium acetate, polyamine compounds such as tetraethylenepentamine, and hydrazide compounds such as adipic acid dihydrazide Small molecule or polymer or the like containing an oxazoline group two or more thereof. The above crosslinking agents may be used singly or in combination of two or more.

<Support>
Next, the support will be described. As the support in the present invention, a solvent non-absorbent support such as a resin-coated paper whose base paper is coated with polyethylene, a solvent-absorbing support such as paper, and the like can be used without limitation.

-Paper substrate-
A paper substrate can be used as the support in the present invention. As described above, when a paper base is used as the support in the present invention, it is preferable to provide an ultrafine particle-containing layer containing the above-described thermoplastic resin. When a paper base material is used as the support, the paper base material can absorb the ink solvent that has permeated through the ultrafine particle-containing layer containing the thermoplastic resin by utilizing the liquid absorbing ability inherent in the paper material. it can.

  Examples of the paper base include natural pulp paper mainly composed of normal natural pulp, mixed paper composed of natural pulp and synthetic fiber, synthetic fiber paper mainly composed of synthetic fiber, polystyrene, polyethylene terephthalate, polypropylene, etc. Any of the so-called synthetic papers obtained by converting the synthetic resin film into pseudo paper may be used, but natural pulp paper (hereinafter simply referred to as “base paper”) is particularly preferable. The base paper may be neutral paper (pH 5-9) or acidic paper, but neutral paper is preferred.

  The above-mentioned base paper is made from natural pulp selected from conifers, hardwoods, etc., as necessary, fillers such as clay, talc, calcium carbonate, urea resin fine particles, rosin, alkyl ketene dimer, higher fatty acid, epoxidized fatty acid amide, A sizing agent such as paraffin wax and alkenyl succinic acid, a starch, a polyamide polyamine epichlorohydrin, a paper strength enhancer such as polyacrylamide, a fixing agent such as a sulfuric acid band and a cationic polymer can be used. Moreover, you may add softening agents, such as surfactant. Furthermore, synthetic paper using synthetic pulp may be used in place of the natural pulp, or a mixture of natural pulp and synthetic pulp in an arbitrary ratio may be used. Among them, it is preferable to use hardwood pulp having short fibers and high smoothness. The water content of the pulp material to be used is preferably in the range of 200 to 500 ml (C.S.F), and more preferably in the range of 300 to 400 ml.

  The paper base material may contain other components such as a sizing agent, a softening agent, a paper strength agent, and a fixing agent. Examples of the sizing agent include rosin, paraffin wax, higher fatty acid salt, alkenyl succinate, fatty acid anhydride, styrene maleic anhydride copolymer, alkyl ketene dimer, epoxidized fatty acid amide, etc. Includes a reaction product of a maleic anhydride copolymer and a polyalkylene polyamine, a quaternary ammonium salt of a higher fatty acid, and the paper strength agent includes polyacrylamide, starch, polyvinyl alcohol, melamine formaldehyde condensate, gelatin In addition, examples of the fixing agent include a sulfuric acid band and a polyamide polyamine epichlorohydrin. In addition, dyes, fluorescent dyes, antistatic agents and the like can be added as necessary.

  The paper substrate is preferably subjected to activation treatment such as corona discharge treatment, flame treatment, glow discharge treatment, plasma treatment and the like before the formation of the ultrafine particle-containing layer described above.

-Resin coated paper-
In the present invention, a resin-coated paper having a resin layer can be used as the support. In this case, as described above, it is preferable to use the above-mentioned water-soluble resin as the binder of the ultrafine particle-containing layer provided between the support and the colorant receiving layer.

  As the paper substrate used for the resin-coated paper, the above-mentioned paper substrate can be used. Specifically, natural pulp paper composed mainly of normal natural pulp, mixed paper made of natural pulp and synthetic fibers, synthetic fiber paper composed mainly of synthetic fibers, synthetic resins such as polystyrene, polyethylene terephthalate, and polypropylene. Any of so-called synthetic papers in which the film is made pseudo-paper may be used, but natural pulp paper (the above base paper) is particularly preferably used. The base paper may be neutral paper (pH 5-9) or acidic paper, but neutral paper is preferred.

  In the base paper, fillers such as alkyl ketene dimer, clay, talc, calcium carbonate, urea resin fine particles, sizing agent such as rosin, higher fatty acid salt, paraffin wax, alkenyl succinic acid, paper strength enhancer such as polyacrylamide, A fixing agent such as a sulfuric acid band can be added. In addition, dyes, pigments, slime control agents, antifoaming agents, etc. are added as necessary. Moreover, a softening agent can be added as needed. With regard to the softening agent, for example, “New Paper Processing Handbook” (edited by Paper Medicine Time), pages 554 to 555 (issued in 1980), particularly those having a molecular weight of 200 or more are preferable. This softening agent is an amine salt or a quaternary ammonium salt having a hydrophobic group having 10 or more carbon atoms and self-fixing with cellulose. Specific examples of the softening agent include a reaction product of a maleic anhydride copolymer and a polyalkylene polyamine, a reaction product of a higher fatty acid and a polyalkylene polyamine, a reaction product of a urethane alcohol and an alkylating agent, Examples include quaternary ammonium salts of fatty acids, and particularly preferred are reaction products of maleic anhydride copolymers and polyalkylene polyamines and reaction products of urethane alcohols and alkylating agents.

The base paper is made by making a pulp slurry containing the above-described pulp and additives such as a filler, a sizing agent, a paper strength reinforcing agent, and a fixing agent added as necessary, using a paper machine such as a long net paper machine, Manufactured by drying and winding. Surface sizing can be performed either before or after this drying. For the surface sizing treatment, a film-forming polymer such as gelatin, starch, carboxymethylcellulose, polyacrylamide, polyvinyl alcohol, or a modified product of polyvinyl alcohol can be used. Examples of modified polyvinyl alcohol include carboxyl group-modified products, silanol-modified products, and copolymers with acrylamide. The coating amount of the film-forming polymer is usually adjusted to 0.1 to 5.0 g / m ² , preferably 0.5 to 2.0 g / m ² . Furthermore, an antistatic agent, a fluorescent brightening agent, a pigment, an antifoaming agent, and the like can be added to the film-forming polymer as necessary.

Moreover, a calendar process can be performed between winding after drying. When the surface treatment is performed after drying, the calender treatment can be carried out before or after the surface treatment, but it is preferable to carry out the calender treatment in the final finishing step after performing various treatments. As the metal roll and the elastic roll used for the calendering process, known ones used for the production of ordinary paper are used. The base paper is finally adjusted to a film thickness of about 50 to 250 μm by the calendar process described above. The density (unit mass) of the base paper is usually 0.8 to 1.3 g / m ² , preferably 1.0 to 1.2 g / m ² .

  In the present invention, a resin layer is provided on at least one surface of the paper base. Applying a treatment to activate the substrate surface, such as corona discharge treatment, flame treatment, glow discharge treatment, plasma treatment, etc. to the paper substrate before coating the resin on the paper substrate has good adhesion on the surface It is preferable to obtain.

  Polyolefin is preferable as the resin constituting the coating resin layer of the paper substrate, but an electron beam cured product of an unsaturated organic compound that can be cured by electron beam irradiation is also effective. The resin layer may be a single layer or a multilayer. Moreover, in the case of a multilayer, lamination | stacking of a polyolefin layer, lamination | stacking of an electron beam cured material layer, lamination | stacking of a polyolefin layer and an electron beam cured material layer, etc. can be used.

  Among the above polyolefins, polyethylene is particularly preferable, but polyester is also effective. As the polyester, polyester of 2,6-naphthalenedicarboxylic acid (NDCA) and ethylene glycol (EG), polyester of NDCA, terephthalic acid and EG, polyethylene terephthalate, and the like are preferable.

  Examples of unsaturated organic compounds that can be cured by electron beam include (1) aliphatic, alicyclic, and aromatic acrylate compounds of 1 to 6-valent alcohols and polyalkylene glycols, and (2) aliphatics and fats. Cyclic and aromatic acrylate compounds obtained by adding alkylene oxide to 1 to 6 valent alcohols, (3) polyacryloylalkyl phosphate esters, (4) reaction products of carboxylic acid, polyol and acrylic acid (5) reaction product of isocyanate, polyol and acrylic acid, (6) reaction product of epoxy compound and acrylic acid, (7) reaction product of epoxy compound, polyol and acrylic acid, etc. .

  Specifically, polyoxyethylene epichlorohydrin modified bisphenol A diacrylate, dicyclohexyl acrylate, epichlorohydrin modified polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, hydroxybivalate ester neopentyl glycol diacrylate, nonylphenoxy polyethylene glycol acrylate , Ethylene oxide modified phenoxylated phosphate acrylate, ethylene oxide modified phthalate acrylate, polybutadiene acrylate, caprolactam modified tetrahydrofurfuryl acrylate, tris (acryloxyethyl) isocyanurate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetra Ak Rate, dipentaerythritol hexaacrylate, polyethylene glycol diacrylate, 1,4-butadiene diol diacrylate, can be used neopentyl glycol diacrylate, and neopentyl glycol-modified trimethylolpropane diacrylate. In the present invention, these compounds can be used alone or in combination of two or more thereof.

The support used in the image recording material of the present invention is not particularly limited. In addition to the above-mentioned paper base material and resin-coated paper, for example, polyesters such as polyethylene terephthalate (PET); polysulfone, polyphenylene oxide, Examples thereof include polyimide, polycarbonate, and polyamide.
Further, a highly glossy opaque support can be used, polyesters such as polyethylene terephthalate (PET), cellulose esters such as nitrocellulose, cellulose acetate, and cellulose acetate butyrate, polysulfone, polyphenylene oxide, polyimide, polycarbonate, polyamide A high gloss film made of a plastic film such as a white pigment or the like made opaque (surface calendering may be applied); and a read-only optical disc such as a CD-ROM or DVD-ROM; A recordable optical disc such as a CD-R and a DVD-R, and a rewritable optical disc can be used as the support. In this case, an ink receiving layer and an ultrafine particle-containing layer can be provided on the label surface side.

  Although the thickness of the said support body is not specifically limited, Usually, it is about 100-250 micrometers, and 150-250 micrometers is preferable.

<Color material receiving layer>
Hereinafter, the image recording material of the present invention will be described by way of an example of an ink jet recording medium having an ink receiving layer formed on the support as a colorant receiving layer for the purpose of receiving ink jet ink. However, the present invention is not limited to this. Is not to be done.

  An image recording material having an ink receiving layer that receives ink as a colorant receiving layer in the present invention (hereinafter referred to as “inkjet recording medium”) has an ultrafine particle-containing layer between the ink receiving layer and the support. Therefore, the glossiness of the image recording surface is maintained while maintaining the flatness and ink absorbability of the surface on which the ink receiving layer is provided (hereinafter sometimes referred to as “image recording surface”). It is possible to prevent the occurrence of image blurring (aging blur) over time.

(Ink receiving layer)
The ink receiving layer preferably comprises at least a water-soluble resin, a cross-linking agent capable of cross-linking the water-soluble resin, fine particles, and a mordant, and further contains other components such as a mordant and a surfactant as necessary. Can be contained.

  The ink receiving layer has a porous structure by containing fine particles, thereby improving the ink absorption performance. In particular, if the solid content of the fine particle ink receiving layer is 50% by mass or more, more preferably more than 60% by mass, it becomes possible to obtain a more favorable porous structure, and the ink absorbability is further improved. be able to. Here, the solid content of the fine particle ink receiving layer is a content calculated based on components other than water in the composition constituting the ink receiving layer.

  The porous ink-receiving layer is a layer having a porosity of 50 to 75%, preferably 60 to 70%. When the porosity is in the range of 50 to 75%, the problem of powder falling due to insufficient binder does not occur. Further, in view of the quality of the ink jet recording medium, the thickness of the ink receiving layer is preferably 20 to 40 μm, and the 60 ° gloss is preferably 30 to 70%.

-Fine particles-
As the fine particles, both organic fine particles and inorganic fine particles can be used. Preferred examples of the organic fine particles include polymer fine particles obtained by, for example, emulsion polymerization, microemulsion polymerization, soap-free polymerization, seed polymerization, dispersion polymerization, suspension polymerization, and the like. Specifically, polyethylene, polypropylene, Examples thereof include powders such as polystyrene, polyacrylate, polyamide, silicone resin, phenol resin, natural polymer, latex or emulsion polymer fine particles, and the like.

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, and zinc oxide. Zinc hydroxide, alumina, aluminum silicate, calcium silicate, magnesium silicate, zirconium oxide, zirconium hydroxide, cerium oxide, lanthanum oxide, yttrium oxide and the like.
Among these, inorganic fine particles are preferable from the viewpoint of ink absorbability and image stability, and silica fine particles, colloidal silica, alumina fine particles, or pseudoboehmite are preferable from the viewpoint of forming a better porous structure.

  Among these, silica fine particles are generally roughly classified into wet method particles and dry method (vapor 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. A method of obtaining anhydrous silica by the (arc method) is the mainstream. The “gas phase method silica” means anhydrous silica fine particles obtained by the gas phase method. As the silica fine particles 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, etc., and exhibits different properties, but is suitable for forming a three-dimensional structure with a high porosity. 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 as small as ² to 3 / nm ² , resulting in sparse soft aggregation (flocculate), resulting in a structure with a high porosity. Presumed.

  Since the above-mentioned vapor phase silica has a particularly large specific surface area, the ink absorbency and retention efficiency are high, and the refractive index is low. Therefore, if the dispersion is carried out 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 sheets such as photo glossy paper. is important.

  The average primary particle diameter of the vapor phase silica is preferably 50 nm or less, more preferably 20 nm or less, particularly preferably 10 nm or less, and most preferably 3 to 10 nm. Vapor phase silica is easy to adhere to each other due to hydrogen bonds with silanol groups, so that when the average primary particle size is 50 nm or less, it can form a structure with a large porosity, effectively improving ink absorption characteristics. Can be made.

  The vapor phase 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.

Furthermore, as the inorganic fine particles, 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. The alumina hydrate 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.

  Regarding the pore structure of the pseudoboehmite, the average pore radius is preferably 1 to 25 nm, and more preferably 2 to 10 nm. The pore volume is preferably 0.3 to 2.0 ml / g [cc / g], more preferably 0.5 to 1.50 ml / g [cc / g]. Here, the pore radius and the pore volume are measured by a nitrogen adsorption / desorption method, and can be measured using, for example, a gas adsorption / desorption analyzer (for example, trade name “Omni Soap 369” manufactured by Coulter).

  Among the alumina fine particles, vapor-phase method alumina fine particles are preferable because of their large specific surface area. The average primary particle diameter of the vapor phase alumina fine particles is preferably 50 nm or less, and more preferably 20 nm or less. Furthermore, colloidal silica having an average primary particle size of 50 nm or less is also preferable.

  The above-mentioned fine particles are, 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, JP-A-2000-43401. 2000-212235, 2000-309157, 2001-96897, 2001-138627, JP-A-11-91242, 8-2087, 8-2090, 8-2091, The embodiments disclosed in JP-A-8-2093, JP-A-8-174992, JP-A-11-192777, JP-A-2001-301314 and the like can also be preferably used.

-Water-soluble resin-
Examples of the water-soluble resin used in the ink receiving layer 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, anions. Modified polyvinyl alcohol, silanol-modified polyvinyl alcohol, polyvinyl acetal, etc.], cellulose resin [methyl cellulose (MC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose , Hydroxypropyl methylcellulose, etc.], chitins, chitosans, starch, resins having an ether bond [polyethylene Oxide (PEO), polypropylene oxide (PPO), polyethylene glycol (PEG), polyvinyl ether (PVE), etc.], resins having a carbamoyl group [polyacrylamide (PAAM), polyvinylpyrrolidone (PVP), polyacrylic acid hydrazide, etc.], etc. Is mentioned. Moreover, the polyacrylic acid salt which has a carboxyl group as a dissociable group, maleic acid resin, alginate, gelatins, etc. can be mentioned. The water-soluble resin can be used alone or in combination of two or more.

Among the above, polyvinyl alcohol resin is particularly 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 2000-18801, JP 2001-213045, JP 2001-328345, JP 8 -324105, JP-A-11-348417, etc. . Examples of the water-soluble resin other than the polyvinyl alcohol resin include compounds described in “0011” to “0014” of JP-A No. 11-165461.
Said water-soluble resin may be used independently and may use 2 or more types together.

  As content of the said water-soluble resin in the said ink receiving layer, 9-40 mass% is preferable with respect to the total solid content mass of an ink receiving layer, and 12-33 mass% is still more preferable. The water-soluble resin and the fine particles described above may be a single material or a mixed system of a plurality of materials.

  Further, from the viewpoint of ensuring the transparency of the ink receiving layer, the type of the water-soluble resin combined with the fine particles, particularly the silica fine particles, is important. When the above-mentioned gas phase method silica is used, it is preferable to combine a polyvinyl alcohol resin as the water-soluble resin, and among them, a polyvinyl alcohol resin having a saponification degree of 70 to 100% is preferable, and a saponification degree of 80 to 99.5%. The polyvinyl alcohol resin is particularly preferable.

  The polyvinyl alcohol-based resin has a hydroxyl group in the structural unit, and since the 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 an ink receiving layer having a porous structure with a high porosity and sufficient strength is formed. In ink-jet recording, the ink receiving layer having a porous structure obtained as described above absorbs ink rapidly by capillarity, and forms dots with good roundness without ink bleeding. Can do.

  Moreover, you may use together said other water-soluble resin for polyvinyl alcohol-type resin. When the other water-soluble resin and the polyvinyl alcohol resin are used in combination, the amount of the polyvinyl alcohol resin is preferably 50% by mass or more, more preferably 70% by mass or more of the total water-soluble resin.

<Content ratio of fine particles and water-soluble resin>
The mass ratio [PB ratio; = x / y] of the mass (x) of the fine particles and the mass (y) of the water-soluble resin greatly affects the film structure and film strength of the ink receiving layer. That is, as the mass 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 PB ratio (x / y) in the ink receiving layer, the decrease in film strength and cracking at the time of drying caused by the PB ratio being too large are prevented, and the PB ratio is too small. From the viewpoint of preventing the ink absorbability from being lowered due to the void being easily blocked by the resin and decreasing the porosity, 1.5 to 10 is preferable.

  In addition, since stress may be applied to the ink jet recording medium when passing through the transport system of the ink jet printer, the ink receiving layer needs to have sufficient film strength and is cut into a sheet shape. In addition, the ink receiving layer needs to have sufficient film strength from the viewpoint of preventing the ink receiving layer from cracking or peeling. In consideration of these, the PB ratio is more preferably 5 or less, and more preferably 2 or more from the viewpoint of ensuring high-speed ink absorbability in an inkjet printer.

For example, a coating solution in which gas phase method silica fine particles having an average primary particle size of 20 nm or less and a water-soluble resin are completely dispersed in an aqueous solution at a PB ratio (x / y) of 2 to 5 is applied on a support and dried. In this case, a three-dimensional network structure in which the secondary particles of silica fine particles are network chains is formed, the average pore diameter is 25 nm or less, the porosity is 50 to 80%, the pore specific volume is 0.5 ml / g or more, A translucent porous film having a specific surface area of 100 m ² / g or more can be easily formed.

-Crosslinking agent-
The ink receiving layer in the present invention is a porous layer in which a layer containing inorganic fine particles and a water-soluble resin further contains a cross-linking agent capable of cross-linking the water-soluble resin, and is cured by a cross-linking reaction between the cross-linking agent and the water-soluble resin. The aspect which is a quality layer is preferable.

As the cross-linking agent, a suitable one may be selected as appropriate in relation to the water-soluble resin contained in the ink receiving layer, and among them, boric acid or a boron compound is preferable in that the cross-linking reaction is rapid. Examples of the boron compound include borax, borate (for example, orthoborate, InBO ₃ , ScBO ₃ , YBO ₃ , LaBO ₃ , Mg ₃ (BO ₃ ) ₂ , Co ₃ (BO ₃ ) ₂ , diborate). (For example, Mg ₂ B ₂ O ₅ , Co ₂ B ₂ O ₅ ), metaborate (for example, LiBO ₂ , Ca (BO ₂ ) ₂ , NaBO ₂ , KBO ₂ ), tetraborate (for example, Na ₂ B ₄ O ₇ · 10H ₂ O), pentaborate (for example, KB ₅ O ₈ · 4H ₂ O, Ca ₂ B ₆ O ₁₁ · 7H ₂ O, CsB ₅ O ₅ ), and the like.

  Of these, borax, boric acid and borates are preferable, and boric acid is more preferable, and it is particularly preferable to use these in combination with polyvinyl alcohol, which is a water-soluble resin, from the viewpoint of causing a rapid crosslinking reaction.

  The crosslinking agent is preferably contained in an amount of 0.05 to 0.50 parts by mass, and more preferably 0.08 to 0.30 parts by mass with respect to 1 part by mass of the water-soluble resin. When the content of the crosslinking agent is within the above range, the water-soluble resin can be crosslinked to effectively prevent cracking and the like.

  In addition, when gelatin is used as the water-soluble resin, boron and the following compounds other than boron compounds can also be used as a crosslinking agent. 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 2,983,611; 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 compounds such as dioxane; Titanium lactate, aluminum sulfate, chromium alum, potash alum, metal-containing compounds such as zirconyl acetate and chromium acetate, polyamine compounds such as tetraethylenepentamine, and hydrazide compounds such as adipic acid dihydrazide A small molecule or polymer or the like containing an oxazoline group two or more. The above crosslinking agents may be used singly or in combination of two or more.

  The cross-linking agent is used in the ink-receiving layer coating liquid and / or the adjacent layer of the ink-receiving layer when applying a coating liquid for forming an ink-receiving layer (hereinafter sometimes referred to as “ink-receiving layer coating liquid”). For the ink-receiving layer containing no cross-linking agent, the ink-receiving layer-coating liquid may be applied to a support on which a coating liquid containing a cross-linking agent has been previously applied. The cross-linking agent can be supplied to the ink receiving layer by, for example, overcoating the cross-linking agent solution after applying and drying the coating liquid.

  For example, the crosslinking agent can be suitably applied as follows. Here, a boron compound will be described as an example. That is, when the ink receiving layer is a layer obtained by crosslinking and curing the coating layer coated with the coating liquid for the ink receiving layer (first liquid), the crosslinking curing is (1) forming the coating layer by coating the coating liquid. At the same time, (2) a basic solution having a pH of 7.1 or higher during the dry coating of the coating layer formed by coating the coating solution and before the coating layer exhibits reduced drying. It can be carried out by applying (second liquid) to the coating layer. The boron compound which is a cross-linking agent may be contained in either the first liquid or the second liquid, and may be contained in both the first liquid and the second liquid. A specific method will be described later.

-Mordant-
In the present invention, a mordant is preferably contained in the ink receiving layer in order to further improve the water resistance and aging resistance of the formed image. As the mordant, any of an organic mordant such as a cationic polymer (cationic mordant) and an inorganic mordant such as a water-soluble metal compound can be used. Of these, organic mordants are preferable, and cationic mordants are particularly preferable.

  The presence of the mordant in at least the upper layer of the ink receiving layer allows interaction with a liquid ink having an anionic dye as a coloring material, thereby stabilizing the coloring material and preventing water resistance and aging resistance. Further improvements can be made.

  In this case, it may be contained in any of the ink receiving layer coating liquid (first liquid) and the basic solution (second liquid) when forming the ink receiving layer, but inorganic fine particles (particularly gas phase method silica). It is preferable to contain and use in the 2nd liquid used as a liquid different from the liquid containing. That is, when the mordant is added directly to the ink receiving layer coating solution, aggregation may occur in the presence of an anion charge-containing silica vapor, but the mordant containing solution and the ink receiving layer coating solution are respectively If the method of independently preparing and coating each is employed, it is not necessary to consider the aggregation of inorganic fine particles, and the range of mordant selection is expanded.

As the cationic mordant, a polymer mordant having a primary to tertiary amino group or a quaternary ammonium base as a cationic functional group is preferably used, but a cationic non-polymer mordant is also used. be able to.
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 (hereinafter referred to as “mordant monomer”), the mordant monomer, Those obtained as copolymers or condensation polymers with other monomers (hereinafter referred to as “non-mordant polymer”) are preferred. These polymer mordants can be used in any form of a water-soluble polymer or water-dispersible latex particles.

  Examples of the 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-Np-vinylbenzyl Ammonium chloride, N, N-dimethyl-Nn-octyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N-benzyl-Np-vinylbenzylammonium chloride, N, N-diethyl-N Benzyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N- (4-methyl) benzyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N-phenyl-Np-vinyl Benzylammonium 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 for their anions.

  Specific examples of the compound include monomethyl diallylammonium 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- (acryloylua) C) ethylammonium chloride, triethyl-2- (acryloylamino) ethylammonium chloride, trimethyl-3- (methacryloylamino) propylammonium chloride, triethyl-3- (methacryloylamino) propylammonium chloride, trimethyl-3- (acryloylamino) Propylammonium chloride, triethyl-3- (acryloylamino) propylammonium chloride;

N, N-dimethyl-N-ethyl-2- (methacryloyloxy) ethylammonium chloride, N, N-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.
Other examples of the copolymerizable monomer include N-vinylimidazole and N-vinyl-2-methylimidazole.

In addition, allylamine, diallylamine, derivatives thereof, salts and the like can also 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, etc.). In addition, since these allylamines and diallylamine derivatives are inferior in polymerizability in the form of amine, it is a general production method to polymerize in the form of a salt and desalting as required.
Further, it is also possible to use a polymerization unit such as N-vinylacetamide or N-vinylformamide, which is converted into a vinylamine unit by hydrolysis after polymerization, and a salt thereof.

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 interact with a dye in an inkjet ink. Or a monomer having a substantially small interaction.
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-methylstyrene; Vinyl esters such as vinyl acetate, vinyl propionate and vinyl versatic acid; 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, specifically, for example, methyl (meth) acrylate or ethyl (meth) acrylate. Propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, (meth) Examples include octyl acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, and the like. Among these, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, and hydroxyethyl methacrylate are preferable. The non-mordant monomers can be used alone or in combination of two or more.

Further, as a cationic mordant, polydiallyldimethylammonium chloride, polymethacryloyloxyethyl-β-hydroxyethyldimethylammonium chloride, polyethyleneimine, polyallylamine and derivatives thereof, polyamide-polyamine resin, cationized starch, dicyandiamide formalin condensate, dimethyl Addition of 2-hydroxypropylammonium salt polymer, polyamidine, polyvinylamine, dicyandiamide-formalin polycondensate, dicyanamide-cachinic resin represented by dicyanamide-diethylenetriamine polycondensate, polyamine-type katine resin, epichlorohydrin-dimethylamine polymer, dimethyldiallylammonium phosphorus chloride -SO ₂ copolymers, diallylamine salt -SO ₂ copolymer, Quaternary ammonium base-substituted alkyl group having an ester moiety (meth) acrylate-containing polymers, styryl polymers having a quaternary ammonium base-substituted alkyl group may be mentioned as being also preferred.

  Specific examples of the cationic mordant include JP-A Nos. 48-28325, 54-74430, 54-124726, 55-22766, 55-142339, 60-23850, and the like. 60-23851, 60-23852, 60-23853, 60-57836, 60-60643, 60-118834, 60-122940, 60-122941, 60- Nos. 122942, 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, 4,227,8353 Nos. 4282305 and 4450224, JP No. 161236, No. 10-81064, No. 10-119423, No. 10-157277, No. 10-217601, No. 11-348409, JP-A No. 2001-138621, No. 2000-43401, No. 2000- 211235, 2000-309157, 2001-96897, 2001-138627, JP-A-11-91242, 8-2087, 8-2090, 8-2091, 8-2093 No. 8-1744992, No. 11-192777, JP-A No. 2001-301314, JP-B-5-35162, No. 5-35163, No. 5-35164, No. 5-88846, JP-A No. 7-8846 No. 118333, Japanese Patent Laid-Open No. 2000-344990, etc., Japanese Patent Nos. 2648847, 266167 Include those such as described in the specification of the issue, and the like. Among them, polyallylamine and derivatives thereof are preferable, and diallyldialkyl cationic polymers are preferable in terms of structure.

  As the polyallylamine or a derivative thereof, various known allylamine polymers and derivatives thereof can be used. Examples of such derivatives include salts of polyallylamine and acids (acids include inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid and nitric acid, methanesulfonic acid, toluenesulfonic acid, acetic acid, propionic acid, cinnamic acid, (meth) An organic acid such as acrylic acid, or a combination thereof, a salt of only a part of allylamine), a derivative of polyallylamine by a polymer reaction, a copolymer of polyallylamine and another copolymerizable monomer Specific examples of the monomer include (meth) acrylic acid esters, styrenes, (meth) acrylamides, acrylonitrile, vinyl esters and the like.

  Specific examples of polyallylamine and derivatives thereof include JP-B-62-31722, JP-B-2-14364, JP-B-63-43402, 63-43403, 63-45721, 63-29881, Japanese Patent Publication No. 1-26362, No. 2-56365, No. 2-57084, No. 4-41686, No. 6-2780, No. 6-45649, No. 6-15592, No. 4-68622, Patents No. 3199227, No. 3008369, JP-A No. 10-330427, No. 11-21321, JP-A No. 2000-281728, No. 2001-106736, JP-A No. 62-256801, JP-A No. 7-173286, 7-213897, 9-235318, 9-302026, 11-21321, WO99 / 2190 No., No. WO99 / nineteen thousand three hundred and seventy-two, JP-A-5-140213, compounds described in JP Kohyo No. 11-506488, and the like.

Among the above-mentioned cationic mordants, diallyl dialkyl cationic polymers are preferable, and diallyl dimethyl cationic polymers are particularly preferable. The cationic mordant is preferably a cationic polymer having a weight average molecular weight of 60000 or less, particularly 40000 or less, from the viewpoint of dispersibility, particularly prevention of thickening.
The cationic mordant is also useful as the fine particle dispersant described above.

  In addition, when a cationic mordant is added to the coating solution for the ink receiving layer, the sulfate ion concentration in the coating solution is preferably 1.5% by mass or less from the viewpoint of preventing thickening of the solution. This sulfate ion is contained in the polymerization initiator at the time of production of the cationic polymer, and since it remains in the polymer, the cationic mordant is formed using a polymerization initiator that does not emit sulfate ion. Is desirable.

  Examples of the inorganic mordant include polyvalent water-soluble metal salts and hydrophobic metal salt compounds. Specific examples of the inorganic mordant include, for example, magnesium, aluminum, calcium, scandium, titanium, vanadium, manganese, iron, nickel, copper, zinc, gallium, germanium, strontium, yttrium, zirconium, molybdenum, indium, barium, Examples include salts or complexes of metals selected from lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, dysprosium, erbium, ytterbium, hafnium, tungsten, bismuth.

  Specific examples of the inorganic mordant include 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 copper (II) chloride 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, basic polyaluminum hydroxide, aluminum sulfite, aluminum thiosulfate, polyaluminum chloride, aluminum nitrate nonahydrate, chloride Aluminum hexahydrate, ferrous bromide, ferrous chloride , Ferric chloride, ferrous sulfate, ferric sulfate, zinc phenolsulfonate, zinc bromide, zinc chloride, zinc nitrate hexahydrate, zinc sulfate, titanium tetrachloride, tetraisopropyl titanate, titanium acetylacetonate , Titanium lactate, Zirconium acetylacetonate, Zirconyl acetate, Zirconyl sulfate, Ammonium zirconium carbonate, Zirconyl stearate, Zirconyl octylate, Zirconyl nitrate, Zirconium oxychloride, Hydroxy zirconium chloride, Chromium acetate, Chromium sulfate, Magnesium sulfate, Magnesium chloride Hydrate, magnesium citrate nonahydrate, sodium phosphotungstate, sodium tungsten citrate, 12 tungstophosphoric acid n hydrate, 12 tungstosilicic acid 26 hydrate, molybdenum chloride, 12 molybdophosphoric acid n Japanese, 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 sulfate, praseodymium nitrate, Examples thereof include neodymium nitrate, samarium nitrate, europium nitrate, gadolinium nitrate, dysprosium nitrate, erbium nitrate, ytterbium nitrate, hafnium chloride, and bismuth nitrate.

Among the inorganic mordants, aluminum-containing compounds, titanium-containing compounds, zirconium-containing compounds, and group IIIB series metal compounds (salts or complexes) are preferable.
Amount of the mordant in the ink-receiving layer is preferably 0.01-5 g / m ^2, more preferably 0.1 to 3 g / m ^2.

-Other ingredients-
In the ink-receiving layer of the present invention, various known additives such as acids, ultraviolet absorbers, antioxidants, fluorescent brighteners, monomers, polymerization initiators, polymerization inhibitors, and blur prevention are optionally added. Agents, preservatives, viscosity stabilizers, antifoaming agents, surfactants, antistatic agents, matting agents, anti-curling agents, water-proofing agents, and the like.

  The ink receiving layer in the invention may contain an acid. By adjusting the surface pH of the ink receiving layer to 3 to 8, preferably 3.5 to 6.0 by adding the above acid, yellowing resistance of the white background can be improved. The surface pH can be measured by the A method (coating method) among the surface PH measurements determined by the Japan Paper Pulp Technology Association (J.TAPPI). For example, Kyoritsu Co., Ltd., which corresponds to the above A method, is available. This can be done using a PH measurement set for paper “Type MPC” manufactured by RIKEN.

  Specific examples of the acid 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 Acid, glutaric acid, gluconic acid, lactic acid, aspartic acid, glutamic acid, salicylic acid, salicylic acid metal salts (Zn, Al, Ca, Mg, etc.), methanesulfonic acid, itaconic acid, benzenesulfonic acid, toluenesulfonic acid, trifluoromethane Sulfonic acid, styrenesulfonic acid, trifluoroacetic acid, barbituric acid, acrylic acid, methacrylic acid, cinnamic acid, 4-hydroxybenzoic acid, aminobenzoic acid, naphthalene disulfonic acid, hydroxybenzenesulfonic acid, toluenesulfinic acid, benzenesulfinic acid , Sulfanilic acid, sulfamic acid, α Resorcinic 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, boric acid, boronic acid, etc. Can be mentioned. The amount of these acids added may be determined so that the surface PH of the ink receiving layer is 3-8.

  The acid may be a metal salt (eg, sodium, potassium, calcium, cesium, zinc, copper, iron, aluminum, zirconium, lanthanum, yttrium, magnesium, strontium, cerium, etc.) or an amine salt (eg, ammonia, triethylamine, (Tributylamine, piperazine, 2-methylpiperazine, polyallylamine, etc.).

In the present invention, it is preferable that the ink receiving layer contains a preservability improving agent such as an ultraviolet absorbent, an antioxidant, or a bleeding inhibitor.
These ultraviolet absorbers, antioxidants, and bleeding inhibitors include alkylated phenolic compounds (including hindered phenolic compounds), alkylthiomethylphenolic compounds, hydroquinone compounds, alkylated hydroquinone compounds, tocopherol compounds, thiodiphenyl ether compounds. Compounds having two or more thioether bonds, bisphenolic compounds, O-, N- and S-benzyl compounds, hydroxybenzyl compounds, triazine compounds, phosphonate compounds, acylaminophenolic compounds, ester compounds, amide compounds, ascorbic acid , Amine antioxidants, 2- (2-hydroxyphenyl) benzotriazole compounds, 2-hydroxybenzophenone compounds, acrylates, water-soluble or hydrophobic metal salts, organometallic compounds , Metal complexes, hindered amine compounds (including TEMPO compounds), 2- (2-hydroxyphenyl) 1,3,5, -triazine compounds, metal deactivators, phosphite compounds, phosphonite compounds, hydroxyamine compounds, nitrone compounds , Peroxide 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 compounds, dihydroxybenzoic acid compounds, trihydroxybenzoic acid compounds and the like.

  Among these, alkylated phenolic compounds, compounds having two or more thioether bonds, bisphenolic compounds, ascorbic acid, amine-based antioxidants, water-soluble or hydrophobic metal salts, organometallic compounds, metal complexes, hindered amines It is preferable to contain at least one of a compound, a polyamine compound, a thiourea compound, a hydrazide compound, a hydroxybenzoic acid compound, a dihydroxybenzoic acid compound, and a trihydroxybenzoic acid compound.

  Specific examples of the compound include Japanese Patent Application No. 2002-13005, Japanese Patent Application Laid-Open No. 10-182621, Japanese Patent Application Laid-Open No. 2001-260519, Japanese Patent Application No. 4-34953, Japanese Patent Application No. 4-34513, Japanese Patent Application Laid-Open No. 11-170686, No. 4-34512, EP 1138509, JP-A-60-67190, JP-A-7-276808, JP-A-2001-94829, JP-A-47-10537, JP-A-58-111942, and JP-A-58-212844. 59-19945, 59-46646, 59-109055, 63-53544, JP 36-10466, 42-26187, 48-30492, 48-31255, 48-41572, 48-54965, 50-10726, U.S. Pat.No. 2,719,086, 3 No. 707,375, the 3,754,919 Patent, the 4,220,711 Patent,

Japanese Patent Publication Nos. 45-4699, 54-5324, European Published Patent Nos. 223739, 309401, 309402, 3105301, 310552, 457416, 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. It is done.

Other additives may be used alone or in combination of two or more. Other additives may be added after being water-solubilized, dispersed, polymer-dispersed, emulsified or formed into oil droplets, or may be encapsulated in microcapsules. Moreover, as addition amount in the case of adding another additive, 0.01-10 g / m < ² > is preferable.

  In order to improve the dispersibility of the fine particles, the surface of the fine particles may be treated with a silane coupling agent. As the silane coupling agent, an organic functional group (for example, vinyl And a group having an amino group (primary to tertiary amino group, quaternary ammonium base), an epoxy group, a mercapto group, a chloro group, an alkyl group, a phenyl group, an ester group, or the like can be preferably used.

  The ink receiving layer (ink receiving layer coating solution) in the present invention preferably contains a surfactant. The surfactant can be appropriately selected from cationic, anionic, nonionic, amphoteric, fluorine and silicone surfactants. Moreover, surfactant may be used individually by 1 type, or may use 2 or more types together.

Examples of the anionic surfactant include fatty acid salts (eg, sodium stearate, potassium oleate), alkyl sulfate esters (eg, sodium lauryl sulfate, triethanolamine lauryl sulfate), and sulfonates (eg, 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 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 glycerol, 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). Alkylene alkyl ethers are preferable. The nonionic surfactant may be contained in either the ink receiving layer coating solution (first solution) or the basic solution (second solution), and may be used alone or in combination of two or more. You can also.

  Examples of the amphoteric surfactants include amino acid type, carboxyammonium betaine type, sulfoammonium betaine type, ammonium sulfate betaine type, imidazolium betaine type, etc., for example, U.S. Pat. No. 3,843,368, Those described in JP-A-59-49535, JP-A-63-236546, JP-A-5-303205, JP-A-8-262742, and JP-A-10-282619 can be suitably used. As the amphoteric surfactant, an amino acid type amphoteric surfactant is preferable, and as the amino acid type amphoteric surfactant, as described in JP-A-5-303205, for example, an amino acid (glycine, glutamic acid, Histidine acid etc.) and N-aminoacyl acids and salts thereof into which long chain acyl groups have been introduced. These can be used alone or in combination of two or more.

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

  The silicone surfactant is preferably a silicone oil modified with an organic group, and can have 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, or a structure in which one end is modified. 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.

  The content of the surfactant in the ink-receiving layer coating solution is preferably 0.001 to 2.0% by mass, and more preferably 0.01 to 1.0% by mass. 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 preferably contains a high boiling point organic solvent for curling prevention. 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.).

<< Preparation of inkjet recording medium >>
In the ink jet recording medium of the present invention, first, an ink receiving layer constituting the medium is coated with a coating liquid (first liquid) and a basic solution (second liquid) for forming an ink receiving layer containing at least fine particles and a water-soluble resin. ) And a coating agent (first solution) is applied onto the ultrafine particle-containing layer of the support to form a coating layer, and (1) the coating solution is further applied. (2) either during the drying of the coating layer formed by coating the coating liquid (first liquid) and before the coating layer exhibits reduced rate drying. In some cases, the basic solution (second liquid) having a pH of 7.1 or higher was applied to the coating layer, and the coating layer was formed by a method of crosslinking and curing (Wet on Wet method). Apply and dry the coating solution for the ultrafine particle-containing layer on the ink receiving layer It can be made by.

  Thus, by adding the mordant to the second liquid, for example, (1) a coating layer (first liquid) containing fine particles, a water-soluble resin, and a crosslinking agent is formed, and the mordant-containing solution (first liquid (2 liquid) is applied by any method, (2) a coating liquid containing fine particles and a water-soluble resin (first liquid) and a mordant-containing solution (second liquid) are applied in multiple layers. Can do. For this reason, since a large amount of mordant can be present near the surface of the ink receiving layer, the coloring material of the ink is sufficiently mordanted, and the water resistance of recorded characters and images can be improved.

  Further, since a large amount of mordant is present in a predetermined portion of the ink receiving layer, it is possible to improve the color density, ink bleeding with time, gloss of the printed part, water resistance of printed characters and images, and ozone resistance. Part of the mordant may be contained in the first liquid. In that case, the mordants of the first liquid and the second liquid may be the same or different.

  An example of preparing a coating solution using the first solution, for example, vapor phase method silica, polyvinyl alcohol, a boron compound, and a cationic polymer will be described below. That is, gas phase method silica is added to water together with a cationic polymer (for example, 10 to 20% by mass), and using a high-speed rotating wet colloid mill (for example, trade name: CLEARMIX, manufactured by M Technique Co., Ltd.) After being dispersed for 20 minutes (preferably 10 to 30 minutes) under high speed rotation conditions of 10,000 rpm (preferably 5000 to 20000 rpm) to form a fine particle dispersion, a boron compound and an aqueous polyvinyl alcohol solution (for example, 1 / of silica amount) are further added. To a mass of about 3) and further dispersing under the same conditions as described above. The obtained coating liquid is a uniform sol, and a porous ink receiving layer having a three-dimensional network structure can be formed by coating and forming this on a support by the following coating method. If necessary, a pH adjuster, other dispersants, surfactants, antifoaming agents, antistatic agents, and the like can be further added to the first liquid.

  In preparing the first liquid and the second liquid, water, an organic solvent, or a mixed solvent thereof can be used as a solvent. Examples of the organic solvent 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.

  The first liquid (ink receiving layer coating liquid) is applied by, for example, a known coating method such as an extrusion die coater, an air doctor coater, a bread coater, a rod coater, a knife coater, a squeeze coater, a reverse roll coater or a bar coater. Can be done.

  The second liquid (basic solution) is applied to the coating layer at the same time as or after the coating of the first liquid (ink receiving layer coating liquid). You may give before it comes to show decremental drying. That is, after the application liquid for the ink-receiving layer is applied, the basic solution is preferably introduced while the applied layer exhibits constant rate drying. This second liquid may contain a mordant.

  Here, “before the coating layer comes to show reduced drying” usually refers to a process for several minutes immediately after the coating of the coating liquid for the ink receiving layer, and during this time, in the coated coating layer This shows a phenomenon of “constant rate drying” in which the content of the solvent (dispersion medium) of the ink decreases in proportion to time. About the time which shows this "constant rate drying", it describes in chemical engineering handbook (pages 707-712, Maruzen Co., Ltd. issue, October 25, 1980), for example.

  As described above, after the application of the first liquid, the coating layer is dried until the coating layer exhibits reduced-rate drying. This drying is generally performed at 40 to 180 ° C. for 0.5 to 10 minutes (preferably, 0.00. 5-5 minutes). The drying time naturally varies depending on the coating amount, but the above range is usually appropriate.

  As a method of applying the second liquid before the reduced rate drying is exhibited, (1) a method of further applying the second liquid onto the coating layer, (2) a method of spraying by a method such as spraying, (3 ) A method of immersing the support on which the coating layer is formed in the second liquid.

  In the above method (1), as the coating method for coating the second liquid, for example, curtain flow coater, extrusion die coater, air doctor coater, bread coater, rod coater, knife coater, squeeze coater, reverse roll coater, bar A known coating method such as a coater can be used. However, it is preferable to use a method in which the coater does not directly contact the already formed first coating layer, such as an extrusion die coater, a curtain flow coater, a bar coater or the like.

The application amount of the second liquid, 5 to 50 g / m ² is generally, 10 to 30 g / m ² is preferred.

  After application of the second liquid, it is generally heated at 40 to 180 ° C. for 0.5 to 30 minutes, and dried and cured. Especially, it is preferable to heat at 40-150 degreeC for 1 to 20 minutes. For example, when the crosslinking agent contained in the first liquid is boric acid or a boron compound (borax or the like), it is preferable to perform heating at 60 to 100 ° C. for 5 to 20 minutes.

  In addition, when the basic solution (second liquid) is applied simultaneously with the application of the ink-receiving layer coating liquid (first liquid), the first liquid and the second liquid are in contact with the support. Thus, the ink receiving layer can be formed by simultaneous application (multilayer application) on the support, followed by drying and curing.

  The simultaneous coating (multilayer coating) can be performed by a coating method using, for example, an extrusion die coater or a curtain flow coater. After the simultaneous coating, the formed coating layer is dried. In this case, the drying is generally performed by heating the coating layer at 40 to 150 ° C. for 0.5 to 10 minutes, preferably 40 to 100. It is carried out by heating at a temperature of 0.5 to 5 minutes.

  When the above simultaneous coating (multilayer coating) is performed by, for example, an extrusion die coater, the two types of liquid discharged simultaneously are in the vicinity of the discharge port of the extrusion die coater, that is, before moving onto the support. In that state, it is coated on the support in multiple layers. Since the two-layer coating liquid layered before coating is likely to cause a cross-linking reaction at the interface between the two liquids when transferred to the support, the two liquids to be ejected are mixed in the vicinity of the discharge port of the extrusion die coater. As a result, thickening is likely to occur, which may hinder the application operation. Therefore, at the time of simultaneous application as described above, it is preferable that simultaneous triple layer application is performed with the barrier liquid (intermediate liquid) interposed between the two liquids together with the application of the first liquid and the second liquid.

  The barrier layer solution can be selected without particular limitation. For example, an aqueous solution containing a trace amount of water-soluble resin, water, and the like can be given. The water-soluble resin is used in consideration of applicability for the purpose of a thickener and the like. For example, a cellulose resin (for example, hydroxypropylmethylcellulose, methylcellulose, hydroxyethylmethylcellulose) And polymers such as polyvinylpyrrolidone and gelatin. The barrier layer solution may contain the above mordant.

  The ink receiving layer uses, for example, a soft calender, a super calender, a gloss calender, etc., and improves the surface smoothness, glossiness, transparency and coating strength by applying a calender treatment through the roll nip under heat and pressure. It is possible.

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

In the case of ink jet recording, the thickness of the ink receiving layer needs to have an absorption capacity sufficient to absorb all of the droplets, and therefore needs to be determined in relation to the porosity in the layer. 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 [mu] m, more preferably 0.01 to 0.025 [mu] m in terms of median diameter. The porosity and the median diameter of the pores can be measured using a mercury porosimeter (trade name “Bore 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.).

<Digital recording materials>
In the case where the toner receiving layer is formed as the color material receiving layer in the present invention, the image forming material in the present invention can be used as a digital recording material.
The digital recording material has a gloss-imparting layer in the present invention and at least one toner-receiving layer on a support, and other layers appropriately selected as necessary, for example, a surface protective layer, an intermediate layer, It comprises an undercoat layer, a cushion layer, a charge control (prevention) layer, a reflection layer, a tint preparation layer, a storage stability improving layer, an adhesion prevention layer, an anti-curl layer, a smoothing layer and the like. Each of these layers may have a single layer structure or a laminated structure.

(Toner receiving layer)
The toner receiving layer is a toner receiving layer for receiving color or black toner and forming an image. The toner receiving layer has a function of receiving toner that forms an image from a developing drum or an intermediate transfer member by (electrostatic) electricity, pressure, or the like in a transfer process, and fixing it by heat, pressure, or the like in a fixing process. Have Further, the toner receiving layer contains at least a thermoplastic resin and, if necessary, other components.

-Thermoplastic resin-
The thermoplastic resin is not particularly limited as long as it can be deformed under temperature conditions such as fixing and can receive toner, and a known thermoplastic resin can be appropriately selected and used. As the thermoplastic resin, those which can satisfy the properties of the toner receiving layer in a state where the toner receiving layer is formed are preferable.

  In addition to the thermoplastic resin, the toner-receiving layer includes a colorant such as a pigment / dye, a plasticizer, a release agent, a slip agent, a matting agent, a filler, a crosslinking agent, a charge control agent, an emulsion, A dispersion etc. can be contained.

  The thermoplastic resin content in the toner receiving layer is preferably 50% by mass or more, and more preferably 50 to 90% by mass.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples. In the examples, an inkjet recording sheet is prepared as an example of the inkjet recording medium. “Part” and “%” in the examples are based on mass unless otherwise specified, and the average molecular weight and the degree of polymerization represent “weight average molecular weight” and “weight average degree of polymerization”, respectively.

[Example 1]
-Production of support A-
1) Preparation of base paper Wood pulp composed of 100 parts of LBKP was beaten to 300 ml of Canadian freeness with a double disc refiner, 0.5 parts of epoxidized behenamide, 1.0 part of anionic polyacrylamide, 0.1 part of polyamide polyamine epichlorohydrin, 0.5 parts of cationic polyacrylamide was added at an absolutely dry mass ratio to the pulp, and weighed with a long net paper machine to make a base paper of 170 g / m ² . Subsequently, in order to adjust the surface size of the base paper, 0.04% of a fluorescent whitening agent (trade name: Whitetex BB, manufactured by Sumitomo Chemical Co., Ltd.) was added to a 4% aqueous solution of polyvinyl alcohol, and this was completely dried. The base paper was impregnated so as to be 0.5 g / m ^{2 in} terms of weight, dried, and then subjected to a calendar treatment to obtain a base paper adjusted to a density of 1.05 g / cm ³ .

2) Preparation of coating liquid A for ultrafine particle containing layer 100 parts of ultrafine titanium dioxide (20% dispersion, trade name: ELCOM-P, average particle diameter 8 nm, refractive index 2.5, manufactured by Catalyst Kasei Kogyo Co., Ltd.) , 114 parts of 35% acrylic latex aqueous dispersion (glass transition temperature 60 ° C., minimum film formation temperature 50 ° C., trade name: Aquabritt 4635, manufactured by Daicel Chemical Industries, Ltd.) and 10 parts of water, Stir and mix. After stirring, the liquid temperature was kept at 15 to 25 ° C. to obtain 26.8% coating solution A for ultrafine particle-containing layer.

3) Formation of ultrafine particle-containing layer On the felt surface (front surface) side of the base paper obtained in 1) above, the coating amount A for ultrafine particle containing layer obtained in 2) above is 15 g / m ^{2 in} dry coating amount. As described above, it was applied using a bar coater and dried to form an ultrafine particle-containing layer (hereinafter, the surface on which the ultrafine particle-containing layer is formed is referred to as “front side”). Subsequently, the same ultrafine particle-containing layer coating liquid as described above is applied to the wire surface opposite to the front side of the base paper (that is, the surface on which the ultrafine particle-containing layer is not formed) with a dry coating amount of 25 g / m ^2. Then, it was applied using a bar coater and dried to provide a curl adjusting layer (hereinafter, the surface on which the curl adjusting layer is formed is referred to as “back surface”). At this time, the coating amount of the ultrafine titanium dioxide dispersion was 5 g / m ² and the acrylic latex coating amount was 10 g / m ² .

4) Soft calender treatment A metal roll using a soft calender provided with a roll pair in which a metal roll and a resin roll are paired to the base paper provided with the ultrafine particle-containing layer and the curl adjusting layer as described above. Was subjected to a soft calendering process under the conditions of a surface temperature of 80 ° C., a nip pressure of 200 kg / cm, and a speed of 100 m / min. This was used as a support (hereinafter referred to as “support A”).

-Preparation of inkjet recording sheet-
1) Preparation of coating solution for ink receiving layer (1) Gas phase method silica fine particles, (2) ion-exchanged water, and (3) a dispersant are mixed, and a dispersing machine (trade name: KD-P, ( (7) Dissolve (4) polyvinyl alcohol, (5) boric acid, and (6) polyoxyethylene lauryl ether in ion-exchanged water after dispersion using Shinmaru Enterprises Co., Ltd. The aqueous solution was added to the above silica dispersion to prepare a coating solution for an ink receiving layer. At this time, the mass ratio between the fine particles and the water-soluble resin (PB ratio = (1) :( 4)) was 4.5: 1, and the pH of the ink receiving layer coating solution was 3.5, indicating acidity. .

<Composition of coating liquid for ink receiving layer>
(1) Gas phase method silica fine particles (fine particles) 10.0 parts (trade name: Leolosil QS-30, average primary particle diameter 7 nm, manufactured by Tokuyama Corporation)
(2) Ion-exchanged water 51.6 parts (3) Dispersant 1.0 part (trade name: Charol DC-902P, 51% aqueous solution, manufactured by Nittobo Co., Ltd.)
(4) Polyvinyl alcohol (water-soluble resin) 8% aqueous solution 27.8 parts (trade name: PVA-124, manufactured by Kuraray Co., Ltd., saponification degree 98.5%, polymerization degree 2400)
(5) Boric acid (crosslinking agent) 0.4 part (6) Polyoxyethylene lauryl ether (surfactant) 1.2 part (trade name: Emulgen 109P (10% aqueous solution), manufactured by Kao Corporation, HLB value 13 .6)
(7) Ion exchange water 33.0 parts

2) Preparation of inkjet recording sheet On the front surface of the support A obtained as described above, the obtained coating solution for ink-receiving layer was applied at an application amount of 200 ml / m ² using an extrusion die coater. Then, it was dried with a hot air dryer at 80 ° C. (wind speed of 3 to 8 m / sec) until the solid content concentration of the coating layer became 20%. During this period, the coating layer exhibited constant rate drying. Immediately after that, it was immersed in a basic solution having the following composition for 30 seconds to deposit 20 g / m ² on the coating layer, and further dried at 80 ° C. for 10 minutes. Thus, an ink jet recording sheet of the present invention having a dry film thickness of 32 μm was produced.

<Composition of basic solution>
・ Boric acid (crosslinking agent) 0.65 part ・ Polyallylamine 12.5 parts (trade name: PAA-03, 20% aqueous solution, manufactured by Nittobo Co., Ltd .; mordant)
・ Ion-exchanged water 72.0 parts ・ Ammonium chloride (surface pH adjuster) 0.8 parts ・ Polyoxyethylene lauryl ether (surfactant) 10 parts (trade name: Emulgen 109P, 2% aqueous solution, HLB value 13.6 , Manufactured by Kao Corporation)
・ 2.0 parts of fluorosurfactant (trade name: MegaFac F1405, 10% aqueous solution, manufactured by Dainippon Ink & Chemicals, Inc.)

[Example 2]
In the preparation of the coating solution for the ultrafine particle-containing layer in “Preparation of Support A” in Example 1, “35% acrylic latex aqueous dispersion (glass transition temperature 60 ° C., minimum film-forming temperature 50 ° C .; Name: Aquabrid 4635, manufactured by Daicel Chemical Industries, Ltd.) “35% acrylic silicone latex aqueous dispersion (glass transition temperature 25 ° C., minimum film-forming temperature 20 ° C .; trade name: Aquabrit Asi- 91, manufactured by Daicel Chemical Industries, Ltd.) "was prepared in the same manner as in Example 1 except that 114 parts were used. At this time, the concentration of the coating solution for the ultrafine particle-containing layer was 26.8%. The coating amount of the ultrafine titanium dioxide dispersion was 5 g / m ² and the coating amount of the acrylic silicone latex was 10 g / m ² .

[Example 3]
In 4) Soft calendering in “Production of support A” in Example 1, instead of performing soft calendering at a metal roll surface temperature of 80 ° C., soft calendering at a metal roll surface temperature of 50 ° C. An ink jet recording sheet of the present invention was produced in the same manner as in Example 1 except for the above.

[Example 4]
In Example 1, instead of the coating solution A for the ultrafine particle-containing layer, the coating solution B for the ultrafine particle-containing layer prepared as follows was used. 4) In the soft calender treatment, the surface temperature of the metal roll was 80 ° C. An ink jet recording sheet of the present invention was produced in the same manner as in Example 1 except that the soft calender treatment was performed at a surface temperature of the metal roll of 40 ° C. instead of the soft calender treatment.

-Preparation of coating solution B for ultrafine particle-containing layer-
100 parts of ultrafine titanium dioxide (trade name: ELCOM-P, 20% dispersion, average particle size 8 nm, refractive index 2.5, manufactured by Catalytic Chemical Industry Co., Ltd.) and 30% acrylic epoxy latex aqueous dispersion ( Product name: Aquabrit AST-483, manufactured by Daicel Chemical Industries, Ltd., glass transition temperature: 35 ° C., minimum film forming temperature: 5 ° C.) and 7 parts of water and 10 parts of water were sufficiently mixed with stirring. .
Thereafter, the temperature of the solution was kept at 15 to 25 ° C. to obtain a coating solution B for an ultrafine particle-containing layer. At this time, the concentration of the coating solution B for the ultrafine particle-containing layer was 17.9%. The coating amount of ultrafine titanium dioxide was 2.3 g / m ² and the coating amount of acrylic epoxy latex was 0.2 g / m ² .

[Example 5]
In Example 1, instead of the coating solution A for the ultrafine particle-containing layer, the coating solution C for the ultrafine particle-containing layer prepared as follows was used. 4) In the soft calender treatment, the surface temperature of the metal roll was 80 ° C. An ink jet recording sheet of the present invention was produced in the same manner as in Example 1 except that the soft calender treatment was performed at a surface temperature of the metal roll of 50 ° C. instead of the soft calender treatment.

-Preparation of coating solution C for ultrafine particle-containing layer-
100 parts of ultrafine titanium dioxide (trade name: ELCOM-P, 20% dispersion, average particle diameter 8 nm, refractive index 2.5, manufactured by Catalytic Chemical Industry Co., Ltd.) and 52% styrene-butadiene latex aqueous dispersion (Trade name: 0696, manufactured by JSR Corporation, glass transition temperature 40 ° C.) 268 parts, 38% acrylic urethane latex aqueous dispersion (trade name: ACRITT WEM-321U, manufactured by Taisei Kako Co., Ltd., glass transition temperature: 20 parts) 53 parts, 50% acrylic styrene latex aqueous dispersion (trade name: Aquabrid 4970, manufactured by Daicel Chemical Industries, Ltd., glass transition temperature 25 ° C., minimum film forming temperature 30 ° C.) 279 parts, water 3 Part of the solution added was thoroughly stirred and mixed.
Thereafter, the temperature of the solution was kept at 15 to 25 ° C. to obtain an ultrafine particle-containing coating solution C. At this time, the concentration of the coating solution C for the ultrafine particle-containing layer was 45.4%. The coating amount of the ultrafine titanium dioxide is 1.7 g / m ^2, the coating amount of the total latex was 0.25.3g / m ^2.

[Example 6]
In the preparation of the coating solution for the ultrafine particle-containing layer in “Preparation of support A” in Example 1, “ultrafine particle titanium dioxide (20% dispersion, trade name: ELCOM-P, average particle diameter 8 nm, refraction) Instead of “rate 2.5, manufactured by Catalyst Kasei Kogyo Co., Ltd.”, “ultrafine zirconia (20% dispersion, trade name: zirconia NZS-30A, average particle size 60 nm, refractive index 2.0, Nissan Chemical Industries, Ltd.) “Inkjet recording sheet of the present invention was produced in the same manner as in Example 1 except that 114 parts” were used. At this time, the concentration of the coating solution for the ultrafine particle-containing layer was 26.8%. Moreover, the coating amount of the ultrafine zirconia dispersion was 5 g / m ² and the acrylic latex coating amount was 10 g / m ² .

[Comparative Example 1]
In Example 1, in place of the coating solution A for the ultrafine particle-containing layer, the coating solution D for the ultrafine particle-containing layer prepared as described below was used in the same manner as in Example 1 for inkjet recording of the comparative example. A sheet was produced.

-Preparation of coating solution D for ultrafine particle-containing layer-
First, 100 parts of titanium dioxide (trade name: Taipei R-780-2, manufactured by Ishihara Sangyo Co., Ltd., average particle size 300 nm, refractive index 2.7) and Na salt of 25% by mass special polycarboxylic acid type polymer (Product name: Demall EP, manufactured by Kao Corporation) 1.2 parts and 121.7 parts of water are mixed, and using a disperser (trade name: NBK-2, manufactured by Nippon Seiki Seisakusho Co., Ltd.). Dispersion gave a 45% titanium dioxide dispersion.

Next, 115 parts of water was obtained from 256 parts above in 256 parts of 35% acrylic latex aqueous dispersion (glass transition temperature 60 ° C., minimum film forming temperature 50 ° C., trade name: Aquabritt 4635, manufactured by Daicel Chemical Industries, Ltd.). The obtained 45% titanium dioxide dispersion (100 parts) was added and sufficiently stirred and mixed. After stirring, the liquid temperature was kept at 15 to 25 ° C. to obtain an ultrafine particle-containing layer coating liquid D.
At this time, the concentration of the coating solution D for the ultrafine particle-containing layer was 28.6%. Moreover, the coating amount of the titanium dioxide dispersion was 5 g / m ² and the coating amount of the acrylic latex was 10 g / m ² .

[Comparative Example 2]
In Example 1, in place of the coating solution A for the ultrafine particle-containing layer, the coating solution E for the ultrafine particle-containing layer prepared as described below was used in the same manner as in Example 1 for inkjet recording of the comparative example. A sheet was produced.

-Preparation of coating solution E for ultrafine particle-containing layer-
First, 31 parts of water was added to 100 parts of 35% acrylic latex aqueous dispersion (glass transition temperature 60 ° C., minimum film forming temperature 50 ° C., trade name: Aquabritt 4635, manufactured by Daicel Chemical Industries, Ltd.), and stirred sufficiently. Mixed. After stirring, the liquid temperature was kept at 15 to 25 ° C. to obtain an ultrafine particle-containing layer coating liquid E.
At this time, the concentration of the coating solution E for the ultrafine particle-containing layer was 26.8%. Further, the coating amount of the titanium dioxide dispersion was 0 g / m ² and the coating amount of the acrylic latex was 15 g / m ² .

[Example 7]
-Production of support B-
1) Preparation of base paper Wood pulp composed of 100 parts of LBKP was beaten to 300 ml of Canadian freeness with a double disc refiner, 0.5 parts of epoxidized behenamide, 1.0 part of anionic polyacrylamide, 0.1 part of polyamide polyamine epichlorohydrin, 0.5 parts of cationic polyacrylamide was added at an absolutely dry mass ratio to the pulp, and weighed with a long net paper machine to make a base paper of 170 g / m ² . Subsequently, in order to adjust the surface size of the base paper, 0.04% of a fluorescent whitening agent (trade name: Whitetex BB, manufactured by Sumitomo Chemical Co., Ltd.) was added to a 4% aqueous solution of polyvinyl alcohol, and this was completely dried. The base paper was impregnated so as to be 0.5 g / m ^{2 in} terms of mass, dried, and then calendered to obtain a base paper adjusted to a density of 1.05 g / cm ³ .

After performing corona discharge treatment on the wire surface (back surface) side of the obtained base paper, high-density polyethylene is coated to a thickness of 19 μm using a melt extruder to form a resin layer consisting of a mat surface (Hereinafter, the resin layer surface is referred to as “back surface”). The resin layer on the back side is further subjected to corona discharge treatment, and then, as an antistatic agent, aluminum oxide (trade name: Alumina Sol 100, manufactured by Nissan Chemical Industries, Ltd.) and silicon dioxide (trade name: Snowtex O, Nissan) A dispersion obtained by dispersing in a mass ratio of 1: 2 with Chemical Industry Co., Ltd.) was applied so that the dry mass was 0.2 g / m ² .

  Further, after the corona discharge treatment is performed on the felt surface (front surface) side where the resin layer is not provided, 10% of anatase-type titanium dioxide, a small amount of ultramarine blue, and 0.01% of a fluorescent brightening agent (for polyethylene) ) And MFR (melt flow rate) 3.8 low density polyethylene is extruded to a thickness of 29 μm using a melt extruder to form a high gloss thermoplastic layer on the surface of the base paper (Hereinafter, this highly glossy surface is referred to as a “front surface”) and used as a support B.

-Preparation of inkjet recording sheet-
After the discharge treatment was performed on the front surface of the support B, an ultrafine particle-containing layer and an ink receiving layer were formed in the same manner as in Example 1 to produce the ink jet recording sheet of the present invention.

[Example 8]
In Example 7, when the ultrafine particle-containing layer was provided, the inkjet recording sheet of the present invention was produced in the same manner as in Example 7 except that the coating solution F for the ultrafine particle-containing layer prepared as follows was used. .

-Preparation of coating solution F for ultrafine particle-containing layer-
100 parts of ultrafine titanium dioxide (trade name: ELCOM-P, 20% dispersion, average particle size 8 nm, refractive index 2.5, manufactured by Catalyst Chemical Industry Co., Ltd.) and 8% aqueous polyvinyl alcohol solution (trade name: PVA124) , Saponification degree 98.5%, polymerization degree 2400, manufactured by Kuraray Co., Ltd.) 1200 parts and ion-exchanged water 83 parts, and further a solution containing 17 parts of boric acid (crosslinking agent) was sufficiently stirred and mixed. .
Thereafter, the temperature of the solution was kept at 15 to 25 ° C. to obtain a coating solution F for an ultrafine particle-containing layer. At this time, the concentration of the coating solution F for the ultrafine particle-containing layer was 8.7%. The coating amount of ultrafine titanium dioxide was 0.2 g / m ² and the coating amount of polyvinyl alcohol was 2.4 g / m ² .

[Comparative Example 3]
A comparative inkjet recording sheet was prepared in the same manner as in Example 7 except that the ultrafine particle-containing layer was not formed in the production of the inkjet recording sheet of Example 7.

<Evaluation>
The following evaluation tests were performed on the present invention and comparative ink jet recording sheets obtained as described above. The results are shown in Table 1 below.

(1) Image clarity (glossiness)
About the white background part of the sheet | seat for inkjet recording, according to JISH8866-2 (1999), incident angle 60 degree | times and light receiving angle 60 using the image clarity measuring device (brand name: ICM-1T, Suga Test Instruments Co., Ltd. product). The C value was obtained by measuring under the conditions of a degree of optical comb width of 2.0 mm, and this was used as an index of glossiness and evaluated according to the following criteria.
[Standard]
A: The C value was 85% or more.
B: The C value was 60 to 85%.
C: The C value was 40 to 60%.
D: The C value was 40% or less.

(2) Image quality evaluation Using an inkjet printer (trade name: PM-970C, manufactured by Seiko Epson Corporation), images of people and landscapes are printed on each inkjet recording sheet, and the image quality is visually evaluated according to the following criteria. evaluated.
[Standard]
A: The image quality was sharp and very good.
B: Image quality was good.
C: Although the image quality is practically acceptable, it is not sufficient.
D: Image quality was poor.

(3) Evaluation of aging blurring Using an inkjet printer (trade name: PM-970C, manufactured by Seiko Epson Corporation), a grid-like linear pattern in which magenta ink and black ink are placed side by side on each inkjet recording sheet. (Line width: 0.28 mm) was printed, and the visual density was measured (OD ₀ ) with a visual densitometer (trade name: X Light 310TR, manufactured by X Light). Then, after printing, it was allowed to stand for 3 hours, and after that, it was stored in a constant temperature and humidity at a temperature of 40 ° C. and a relative humidity of 90% for 1 day. After storage, the visual density (OD ₁ ) was measured again with a visual densitometer and evaluated according to the following criteria based on the density difference (ΔOD = OD ₀ −OD ₁ ). The smaller the density difference (ΔOD), the more the occurrence of aging blur is suppressed.
A: ΔOD was 0.15 or less.
B: ΔOD was more than 0.15 and less than 0.25.
C: ΔOD was 0.25 or more.

As shown in Table 1 above, in Examples 1 to 6 in which the ultrafine particle-containing layer was provided, high glossiness could be obtained while using the paper base material as a support. Further, Examples 7 and 8 composed of polyethylene resin-coated paper were able to obtain a higher gloss feeling than Comparative Example 3 in which the ultrafine particle-containing layer was not provided.
Furthermore, Examples 1-6 using a paper base material were excellent also in the suppression effect of aging blur with respect to image quality. Further, even in Example 3 in which the calendar treatment was performed at a low temperature, a sufficient glossiness could be obtained by providing the ultrafine particle-containing layer.

  On the other hand, Comparative Example 1 using titanium dioxide having a large particle diameter instead of ultrafine particle titanium dioxide did not provide sufficient gloss. Moreover, about the comparative example 2 which did not use titanium dioxide, both glossiness and the image quality were inferior.

Claims (15)

  An image recording material having at least a color material receiving layer on a support, wherein the refractive index is 1.9 or more and the average particle diameter is 100 nm or less between the support and the color material receiving layer. An image recording material comprising at least one layer containing an ultrafine inorganic compound.   The image recording material according to claim 1, wherein the ultrafine inorganic compound is at least one selected from titanium dioxide and zirconia.   The image recording material according to claim 1 or 2, wherein the content of the ultrafine inorganic compound in the layer containing the ultrafine inorganic compound is 5 to 95% by mass.   The image recording material according to claim 1, wherein the support is a paper substrate, and the layer containing the ultrafine inorganic compound contains a thermoplastic resin. The image recording material according to claim 4, wherein the coating amount of the layer containing the ultrafine inorganic compound is ² to 30 g / m ² .   The thermoplastic resin is selected from acrylic latex, acrylic silicone latex, acrylic epoxy latex, acrylic styrene latex, acrylic urethane latex, styrene-butadiene latex, acrylonitrile-butadiene latex, and vinyl acetate latex. The image recording material according to claim 4, wherein the image recording material is at least one kind.   The image recording material according to any one of claims 4 to 6, wherein the thermoplastic resin has a glass transition temperature of 5 to 70 ° C and a minimum film forming temperature of 5 to 60 ° C. .   After forming the layer containing the ultrafine inorganic compound on the paper substrate, using a calender in which at least one of the roll pairs is composed of a metal roll, the surface temperature of the metal roll is changed to the glass transition of the thermoplastic resin. The image recording material according to any one of claims 4 to 7, wherein the image recording material is calendered at a temperature equal to or higher than a temperature and at a nip pressure of the roll pair of 50 to 400 kg / cm.   The support is a resin-coated paper having a resin layer on the side where at least the layer containing the ultrafine inorganic compound is provided, and the layer containing the ultrafine inorganic compound contains a water-soluble resin. The image recording material according to claim 1, wherein the image recording material is an image recording material. The image recording material according to claim 9, wherein a coating amount of the layer containing the ultrafine inorganic compound is 0.05 to 20 g / m ² .   The water-soluble resin is at least one selected from a polyvinyl alcohol resin, a cellulose resin, a resin having an ether bond, a resin having a carbamoyl group, a resin having a carboxyl group, and gelatins. Item 15. The image recording material according to Item 9 or 10.   The image recording material according to claim 1, wherein the colorant receiving layer is an ink receiving layer.   The image recording material according to claim 12, wherein the ink receiving layer contains a water-soluble resin, a cross-linking agent capable of cross-linking the water-soluble resin, fine particles, and a mordant.   The ink receiving layer includes, as the water-soluble resin, at least one selected from a polyvinyl alcohol resin, a cellulose resin, a resin having an ether bond, a resin having a carbamoyl group, a resin having a carboxyl group, and gelatins. The image recording material according to claim 13, wherein the fine particle contains at least one selected from silica fine particles, colloidal silica, alumina fine particles, and pseudoboehmite.   The ink receiving layer is a layer obtained by crosslinking and curing a coating layer coated with a coating solution containing at least the fine particles and the water-soluble resin, and the crosslinking curing is applied to the coating solution and / or the following basic solution. A cross-linking agent is added and (1) the coating layer is formed by coating the coating solution, or (2) the coating layer formed by coating the coating solution is in the process of being dried. The image recording material according to claim 13, wherein the image recording material is applied by applying a basic solution having a pH of 7.1 or higher to the coating layer at any time before the ink exhibits reduced-rate drying.