JP2003326843A - Ink jet recording sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink jet recording sheet which is free from bleeding over time and shows outstanding resistance to light and ozone. <P>SOLUTION: In the ink jet recording sheet with a coloring material receiving layer formed on a support, the coloring material receiving layer contains an inorganic fine particle, a polymer having a primary, a secondary and a tertiary amino group and a silane coupling agent having a functional group which forms a bond through a chemical reaction with the amino groups. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid ink such as an aqueous ink (using a dye or a pigment as a coloring material) and an oil-based ink, or a solid ink which is solid at room temperature and is melted and liquefied before printing. Regarding the recording material supplied to ink jet recording using ink or the like, for details,
The present invention relates to an inkjet recording sheet having excellent light resistance and ozone resistance.

[0002]

2. Description of the Related Art In recent years, with the rapid development of the information technology industry, various information processing systems have been developed, and a recording method and a recording apparatus suitable for the information processing system have also been developed.
Each has been put to practical use. Among these recording methods, the inkjet recording method is not limited to offices, because it is capable of recording on various types of recording materials, has a relatively inexpensive hardware (device) and is compact, and has excellent quietness. , Has also been widely used in so-called home use.

Further, with the recent increase in resolution of ink jet printers, it has become possible to obtain so-called photograph-like high quality recorded matter. With the progress of such hardware (device), ink jet recording is possible. Various recording sheets have been developed. The properties required for the recording sheet for inkjet recording are generally (1) quick-drying property (high ink absorption speed), and (2) proper and uniform ink dot diameter. (No bleeding), (3) good graininess, (4) high dot roundness, (5) high color density, (6) high saturation (dullness No)), (7) Water resistance, light resistance, and ozone resistance of the printed area are good, (8) Whiteness of the recording sheet is high,
(9) The storage stability of the recording sheet is good (no yellowing coloring occurs even after long-term storage, images do not bleed after long-term storage (good aging blur)), and (10) stable and dimensional stability And the curl is sufficiently small, and (11) hard running property is good. Further, in the use of photo glossy paper used for the purpose of obtaining so-called photo-like high quality recorded matter, in addition to the above-mentioned characteristics, glossiness, glossiness of printed area, surface smoothness, and silver salt photograph are similar. The texture of photographic paper is also required.

In order to improve the above-mentioned various properties, an inkjet recording sheet having a porous structure in the colorant receiving layer has been developed and put into practical use in recent years. Since such an inkjet recording sheet has a porous structure, it has excellent ink receptivity (quick drying) and high gloss.

For example, in JP-A-10-119423 and JP-A-10-217601, a coloring material receiving layer containing fine inorganic pigment particles and a water-soluble resin and having a high porosity is provided on a support. Ink jet recording sheets have been proposed. These recording sheets, particularly ink jet recording sheets provided with a coloring material receiving layer having a porous structure using silica as the inorganic pigment fine particles, have excellent ink absorbability due to the constitution and form a high resolution image. It has a high ink receiving performance to be obtained and can exhibit high gloss.

However, since these are porous films, they have a high oxygen permeability and may accelerate the deterioration of the components contained in the colorant receiving layer. Further, image bleeding over time (hereinafter referred to as "time bleeding") may occur due to water adsorption on the silica surface.

On the other hand, there has been proposed an ink jet recording material containing a compound having an ammonium salt, particularly a polymer compound having the same for the purpose of fixing a dye component in ink. For example, (co) polymers of diallylammonium salt derivatives described in JP-A-59-20696 and JP-A-64-75281, JP-A-6-3
(Meth) acrylates having an ammonium salt described in JP-A-40163, JP-A-10-272830, and the like.
(Meth) acrylamide (co) polymer, JP-A-6-2
Many compounds are used such as amine-epichlorohydrin polyaddition products described in JP-A-34268 and polyamidines described in JP-A No. 11-58934. However, in these ink jet recording sheets,
If the printed image is stored in a clear file or the like immediately after printing, or if it is stored for a long time under high humidity conditions, there is still a problem that blurring of the image still occurs. On the other hand, Japanese Patent Application Laid-Open No. 62-178384 and Japanese Patent Publication No. 3-24905 disclose recording sheets having a colorant receiving layer containing silica particles surface-treated with a silane coupling agent. However, these are
The purpose is to improve the adhesiveness with the support and the blurring immediately after printing, or to improve the light resistance by reducing the surface activity of silica particles, and to suppress the blurring over time under high humidity conditions. It is difficult.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and achieve the following objects. That is, the object of the present invention is capable of forming a high-resolution and high-density image, excellent in light resistance, and after printing, even when stored for a long time in a high temperature and high humidity environment, it does not cause bleeding with time, and is stable. Holds images and resists gas (ozone)
An object is to provide an inkjet recording sheet having excellent properties.

[0009]

In view of such circumstances, the inventor of the present invention has made earnest studies and found that the coloring material receiving layer on the support contains inorganic fine particles and a primary, secondary, or tertiary layer. The present invention has been completed by finding that an ink jet recording sheet containing a polymer having an amino group and a silane coupling agent having a functional group capable of forming a bond by the reaction with the amino group can solve the above problems. That is, the present invention provides the following.

<1> In an ink jet recording sheet having a color material receiving layer on a support, the color material receiving layer comprises inorganic fine particles and a polymer having a primary, secondary or tertiary amino group. An ink jet recording sheet comprising a silane coupling agent having a functional group capable of forming a bond by a reaction with an amino group. <2> The inkjet recording sheet according to <1>, wherein the silane coupling agent is represented by the following general formula (1).

[Chemical 2] [In the formula, X ¹ is an alkoxy group having 1 to 8 carbon atoms or an aryloxy group, and X ² is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms which may contain a saturated or unsaturated cyclic structure, a carbon atom Represents an alkoxy group or an aryloxy group of the formulas 1 to 8, and Y represents an (n + 1) -valent linking group which may have a substituent or may have a heteroatom interposed. R represents a group capable of forming a covalent bond by reaction with a primary, secondary or tertiary amino group. n is an integer of 1 to 3, and m is 1 or 2. <3> The polymer having an amino group is one kind or two or more kinds selected from polyallylamine, polyvinylamine, polyethyleneimine and derivatives thereof <1>
Alternatively, the inkjet recording sheet according to <2>. <4> R in the general formula (1) is an epoxy group <
<2> or <3> the inkjet recording sheet <5> The inorganic fine particles are one or more selected from silica fine particles, alumina fine particles, and pseudo-boehmite, and <1> to <4>> The ink jet recording sheet according to any one of <1>. <6> The ink jet recording sheet according to any one of <1> to <5>, wherein the color material receiving layer further contains a water-soluble resin. <7> The water-soluble resin is a polyvinyl alcohol resin,
One or more selected from a cellulosic resin, a resin having an ether bond, a resin having a carbamoyl group, a resin having a carboxyl group and gelatins <6.
The ink jet recording sheet according to the item>. <8> The inkjet recording sheet according to <6> or <7>, wherein the color material receiving layer further contains a crosslinking agent capable of crosslinking the water-soluble resin. <9> The coloring material receiving layer is formed by coating the surface of the support with the coating liquid A containing fine particles and a water-soluble resin, and (1) simultaneously with the coating, and (2) drying the coating layer formed by the coating. 1 on the way, before the coating layer shows a reduction rate drying, or (3) after drying the coating layer to form a coating film, 1
Obtained by applying a coating liquid B containing a polymer having a secondary, secondary or tertiary amino group, and a silane coupling agent different from the coating liquid A, the coating liquid B, and the coating liquids A and B. The inkjet recording sheet according to any one of <1> to <8>, which is obtained by adding and applying it to at least one of the coating liquids C. <10> An inkjet recording sheet according to <9>, wherein a crosslinking agent is further added to at least one of coating liquids A, B and C to make the coating liquid B a basic solution having a pH of 8 or more. .

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the ink jet recording sheet of the present invention, the coloring material receiving layer on the support is composed of inorganic fine particles and 1
It is characterized by containing a polymer having a secondary, secondary or tertiary amino group and a silane coupling agent having a functional group capable of forming a bond by the reaction with the amino group.

(Silane Coupling Agent) The silane coupling agent used here is preferably one represented by the following general formula (1).

[0013]

[Chemical 3]

[In the formula, X ¹ is an alkoxy group having 1 to 8 carbon atoms or an aryloxy group, and X ² is a hydrogen atom, or a C 1 group which may contain a saturated or unsaturated cyclic structure.
To 18 alkyl group, an alkoxy group having 1 to 8 carbon atoms or an aryloxy group, and Y represents an n + 1 valent linking group which may have a substituent or may have a heteroatom. R represents a group capable of forming a covalent bond by reaction with a primary, secondary or tertiary amino group. n is an integer of 1 to 3, and m is 1 or 2. ]

The alkyl group has 1 to 18 carbon atoms, preferably 1 to 8 carbon atoms. If the carbon number exceeds 18, the reactivity with the inorganic pigment fine particles may decrease.
Examples of the alkyl group include a methyl group, an ethyl group,
Examples thereof include a propyl group, a butyl group, a hexyl group, an octyl group, a decyl group, a dodecyl group, a tetradecyl group and an octadecyl group, and a methyl group, an ethyl group, a propyl group and a butyl group are preferable. The alkoxy group has 1 to 8 carbon atoms, preferably 1 to 4 carbon atoms. When the carbon number exceeds 8, the reactivity with the inorganic pigment fine particles may decrease.
Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a hexyloxy group and an octyloxy group, and a methoxy group, an ethoxy group and a propoxy group are preferable. The aryloxy group is preferably a phenoxy group, a methylphenoxy group, a nitrophenoxy group, a methoxyphenoxy group or a naphthoxy group, and particularly preferably a phenoxy group or a methylphenoxy group.

In the general formula (1), Y may have a substituent or may have a total of 1 to 18 carbon atoms which may be through a hetero atom.
Represents an n + 1-valent linking group. The total number of carbon atoms in Y is 2 to
8 is preferable. When the carbon number exceeds 18, the solubility in water or alcohol solvent is lowered and sufficient performance may not be obtained. Y is an alkylene group (for example, a methylene group, an ethylene group, a propylene group, a tetramethylene group, a hexamethylene group, an octamethylene group, etc.), an alkylidyne group (for example, a methylidyne group), an arylene group (for example, phenylene group). Group), -O-, -COO-, -OCO-, -NH-, or at least any linking group selected from a combination thereof. Examples of the substituent include a halogen atom, a hydroxyl group, an amino group, an ester group, an ether group, an amide group and the like. As the above hetero atom,
Examples thereof include an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom and a phosphorus atom, and an oxygen atom, a nitrogen atom and a sulfur atom are preferable. The R is not particularly limited as long as it is a group capable of forming a covalent bond by reaction with primary, secondary, and tertiary amino groups. Specific examples of R include an epoxy group, an oxetane group, a thiirane group, an isocyanate group, an isothiocyanate group, a lactone group, a cyclic carbonate group, an acryloyl group, an aldehyde group, and an acetoacetyl group halogen group (Cl, Br, I). Can be mentioned. Of these, epoxy groups are particularly preferred. Specific examples of the silane coupling agent represented by the formula (1) include the following compounds.

[0017]

[Chemical 4]

The silane coupling agent used in the present invention is 1
They may be used alone or as a mixture of two or more. The total content of the above-mentioned treatment agents contained in the color material receiving layer is preferably 0.001 to 20% by mass of the inorganic fine particles, and more preferably 0.05 to 10% by mass. When the total content is within this range, the ink receptivity and durability of the inkjet recording sheet are further improved. If the total content is less than 0.001% by mass of the inorganic pigment fine particles, the light resistance and gas resistance may be insufficient, and if it exceeds 20% by mass, the ink receptivity may decrease.

When the silane coupling agent is contained in the color material receiving layer, it is added to the coating solution for the color material receiving layer in the form of an aqueous solution. Alternatively, a water-soluble organic solvent such as an alcohol compound (methanol, ethanol, isopropyl alcohol, ethylene glycol, diethylene glycol,
Diethylene glycol monobutyl ether, polyethylene glycol, polypropylene glycol, glycerin, diglycerin, trimethylolpropane, trimethylolbutane, etc.), ether compounds (tetrahydrofuran, dioxane, etc.), amide compounds (dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc.), A ketone compound (acetone or the like) may be mixed and added to the coloring material-receptive layer coating solution in a state where the affinity for water is increased.

When the silane coupling agent does not have sufficient water solubility, a hydrophobic organic solvent such as an ester compound (ethyl acid acid ester, dioctyl adipate, butyl phthalate, methyl stearate, tricresyl phosphate) is used. Etc.), ether compounds (anisole, hydroxyethoxybenzene, hydroquinone dibutyl ether, etc.), hydrocarbon compounds (toluene, xylene, diisopropylnaphthalene, etc.), amide compounds (N-butylbenzenesulfonamide, stearic acid amide, etc.),
An alcohol compound (2-ethylhexyl alcohol, benzyl alcohol, phenethyl alcohol, etc.), a ketone compound (hydroxyacetophenone, benzophenone, cyclohexane, etc.), or the above water-soluble organic solvent may be mixed and added. The form when added is
Oil drops, latex, solid dispersion, polymer dispersion and the like may be used.

The total content of the silane coupling agent represented by the formula (1) in the ink jet recording sheet is preferably 0.1 to 10 g / m ² , and 0.2 to 5 g / m ^2.
m ² is more preferable. If the total content is less than 0.1 g / m ² or more than 5 g / m ² , the image density after printing may decrease.

(Polymer Having Primary, Secondary, and Tertiary Amino Group) In the present invention, the colorant-receiving layer has the above general formula (1) in order to improve water resistance of an image and prevent bleeding over time. Forming at least a primary bond with a compound represented by 2
Polymers having either primary or tertiary amino groups are included. Examples of the polymer having an amino group include polyallylamine, polyvinylamine, polyethyleneimine, and derivatives thereof. Among them, the weight average molecular weight is 10,000 in view of prevention of bleeding with time.
Polyallylamine of 0 or less and its derivatives are particularly preferable.

(Polyallylamine or its derivative) As the polyallylamine or its derivative of the present invention, various known allylamine polymers and their derivatives can be used. As such a derivative, a partially neutralized salt of polyallylamine and an acid (as the acid, an inorganic acid such as hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid, methanesulfonic acid, toluenesulfonic acid, acetic acid, propionic acid, cinnamic acid, Organic acids such as (meth) acrylic acid, or combinations thereof, and derivatives of polyallylamine by polymer reaction (for example, polymers containing repeating units represented by the following formulas (1) to (6),
However, the total content of the units represented by (1), (4), and (6) is 10 to 100 mol%, and (2), (3), and (5)
The total content of the units represented by is 0 to 90 mol%),
Copolymers of polyallylamine and other copolymerizable monomers (specific examples of the monomers include (meth) acrylic acid esters, styrenes, (meth) acrylamides,
Acrylonitrile, vinyl esters, etc.).

[0024]

[Chemical 5]

[In the formula, R ¹ , R ² , R ³ and R ⁴ represent an organic group, and R ⁵ and R ⁶ have the same meanings as R ¹ , R ² , R ³ and R ⁴ or represent a hydrogen atom. R ⁷ represents a hydrogen atom, a methyl group, a hydroxyl group, or a thiol group. R ⁸ is COOR ⁹ , CN, CONR
¹⁰ R ^{11 represents} an alkyl group, an aryl group, or an aralkyl group, which may all have a substituent. Where R
⁹ , R ¹⁰ and R ¹¹ are each a hydrogen atom, an alkyl group (the alkyl group may have a branched or cyclic structure, and may have an unsaturated bond or a substituent), an aryl group (having a substituent). May be present) and an aralkyl group (which may have a substituent). X represents a counter anion. ]

Here, the organic group is a group containing a hydrocarbon moiety and / or a hydrogen halide moiety. In addition to this, hydrogen, carbon, nitrogen, oxygen, sulfur, phosphorus, silicon, boron,
It may contain an atom such as halogen and / or a functional group consisting of a combination thereof. Examples of such a group include (substituted) alkyl group, (substituted) aralkyl group, (substituted) aryl group, (substituted) ) Acyl group, (substituted)
Examples thereof include a sulfonyl group and heterocycles. R ¹ ,
Specific examples of the organic group represented by R ² , R ³ and R ⁴ include alkyl groups (for example, methyl, ethyl, n-propyl, i-
Propyl, n-butyl, sec-butyl, t-butyl,
n-hexyl, cyclohexyl, n-octyl, 2-ethylhexyl, n-decyl, n-dodecyl, octadecyl, 1,3-butadienyl, 1,3-pentadienyl, etc., aralkyl group (for example, benzyl, phenylethyl, vinylbenzyl, 1-phenylvinyl, 2-phenylvinyl, etc.) and aryl groups (eg, phenyl, naphthyl, tolyl, vinylphenyl, etc.).

Further, those having a substituent include a fluoroethyl group, a trifluoroethyl group, a methoxyethyl group, a phenoxyethyl group, a hydroxyphenylmethyl group, a chlorophenyl group, a dichlorophenyl group, a trichlorophenyl group, a bromophenyl group and an iodophenyl group. , A fluorophenyl group, a hydroxyphenyl group, a methoxyphenyl group, a hydroxyphenyl group, an acetoxyphenyl group, a cyanophenyl group and the like. Moreover, as a thing containing a hydroxyl group, the group etc. which are shown below are mentioned.

[0028]

[Chemical 6]

R ⁷ represents a hydrogen atom, a methyl group, a hydroxyl group, or a thiol group. R ⁸ is COOR ⁹ , C
N, CONR ¹⁰ R ¹¹ , an alkyl group, an aryl group, and an aralkyl group are shown, and all of them may have a substituent. Here, R ⁹ , R ¹⁰ and R ¹¹ are each a hydrogen atom, an alkyl group (the alkyl group may have a branched or cyclic structure, and may have an unsaturated bond or a substituent), and an aryl group (having a substituent It may have) or an aralkyl group (which may have a substituent).

Specific examples of R ⁹ , R ¹⁰ and R ¹¹ include hydrogen, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, n-hexyl group, cyclohexyl group, n-octyl group, 2-ethylhexyl group, n-decyl group, n-dodecyl group, octadecyl group, allyl group, benzyl group, phenyl group, naphthyl group, biphenyl group ,
1,1,1-trifluoroethyl group, 2-hydroxy-3
-Chloropropyl group and the like can be mentioned. Specific examples of X ⁻ include halogen ion (Cl ⁻ , Br ⁻ , I ⁻ ), sulfonate ion, alkyl sulfonate ion, aryl sulfonate ion, alkyl carboxylate ion, aryl carboxylate ion, and the like.

The structures of these derivatives are not particularly limited, but it is preferable that the resulting polymer is water-soluble or soluble in an organic solvent miscible with water, but the form of water-dispersible latex particles. But it can be used.

The total content of the above-mentioned polyallylamine or derivatives thereof in the ink jet recording sheet is preferably 0.1-5 g / m ² , and 0.2-3.
g / m ² is more preferable. The total content is 0.1 g / m ²
If it is less than 5, the blurring with time may be insufficient.
If it exceeds g / m ² , the ink absorbency may decrease.

(Fine Particles) The colorant receiving layer of the ink jet recording sheet of the present invention contains fine inorganic particles. The coloring material receiving layer of the ink jet recording sheet has a porous structure by containing fine particles, which improves the ink absorbing performance. In particular, the solid content of the fine particles in the color material receiving layer is 50% by mass or more, more preferably 6
When it exceeds 0% by mass, it is possible to form a better porous structure, and an inkjet recording sheet having sufficient ink absorbency can be obtained, which is preferable. Here, the solid content in the coloring material receiving layer of the fine particles,
It is the content calculated based on components other than water in the composition constituting the colorant receiving layer. The fine particles used in the present invention are inorganic fine particles, but organic fine particles can be used as long as they do not impair the effects of the present invention.

Preferable examples of the above organic fine particles include fine polymer particles obtained by emulsion polymerization, microemulsion polymerization, soap-free polymerization, seed polymerization, dispersion polymerization, suspension polymerization, and the like. , Polypropylene, polystyrene, polyacrylate, polyamide, silicone resin, phenol resin, natural polymer powder, latex or emulsion polymer 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 oxidation. Examples thereof include zinc, zinc hydroxide, alumina, aluminum silicate, calcium silicate, magnesium silicate, zirconium oxide, zirconium hydroxide, cerium oxide, lanthanum oxide and yttrium oxide. Among these, silica fine particles, colloidal silica, alumina fine particles or pseudo-boehmite are preferable from the viewpoint of forming a good porous structure. The fine particles may be used as primary particles as they are, or may be used in a state where secondary particles are formed. The average primary particle size of these fine particles is preferably 2 μm or less, more preferably 200 nm or less. Furthermore, silica fine particles having an average primary particle size of 20 nm or less, colloidal silica having an average primary particle size of 30 nm or less,
Alumina fine particles having an average primary particle diameter of 20 nm or less, or pseudo-boehmite having an average pore radius of 2 to 15 nm is more preferable, and silica fine particles, alumina fine particles, and pseudo-boehmite are particularly preferable.

Silica fine particles are generally classified into wet method particles and dry method (gas phase method) particles according to their production methods. In the above-mentioned wet method, a method in which activated silica is generated by acid decomposition of a silicate, and the activated silica is appropriately polymerized and coagulated and precipitated to obtain hydrous silica is the mainstream. On the other hand, the vapor phase method is a method by high temperature vapor phase hydrolysis of silicon halide (flame hydrolysis method),
Silica sand and coke are heated and reduced by an arc in an electric furnace to be reduced and vaporized, and a method of obtaining anhydrous silica by a method of oxidizing this with air (arc method) is the mainstream. It means anhydrous silica fine particles obtained by the method. As the silica fine particles used in the present invention, vapor phase method silica fine particles are particularly preferable.

The vapor phase silica has different properties from the hydrous silica, such as the density of silanol groups on the surface and the presence / absence of pores, and shows different properties. ing. Although the reason for this is not clear, in the case of hydrous silica, the density of silanol groups on the surface of the fine particles is as high as 5 to 8 / nm ² , and the silica fine particles are likely to be densely aggregated (aggregate). In the case of the method silica, since the density of silanol groups on the surface of the fine particles is as few as 2-3 / nm ^2, it is assumed that sparse soft agglomeration (flocculate) occurs, resulting in a structure with a high porosity. To be done.

Since the above-mentioned vapor grown silica has a particularly large specific surface area, it has high ink absorption and retention efficiency, and has a low refractive index. Is provided, and high color density and good color developability are obtained. The transparency of the receiving layer is not only for applications requiring transparency such as OHP, but also for obtaining high color density and good color forming 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 30 nm or less, more preferably 20 nm or less, particularly preferably 10 nm or less, most preferably 3 to 10 nm. In the vapor phase silica, particles are easily attached to each other by hydrogen bonds due to silanol groups. Therefore, when the average primary particle diameter is 30 nm or less, a structure having a large porosity can be formed, and ink absorption characteristics can be effectively improved. Can be improved.

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

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

Regarding the pore structure of pseudo-boehmite, its average pore radius is preferably 1 to 30 nm, and 2 to 15 nm.
Is more preferable. The pore volume is 0.3 to 2.0.
cc / g is preferable, and 0.5 to 1.5 cc / g is more preferable. Here, the measurement of the pore radius and the pore volume,
It is measured by a nitrogen adsorption / desorption method and can be measured by, for example, a gas adsorption / desorption analyzer (for example, trade name "Omnisorb 369" manufactured by Coulter, Inc.). 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 grown alumina is preferably 30 nm or less, more preferably 20 nm or less.

When the above-mentioned fine particles are used for an ink jet recording sheet, for example, JP-A-10-81064 is used.
No. 10-119423 and No. 10-157277.
No. 10-217601 and No. 11-348409.
No. 2001-138621 and 2000-43.
401, 2000-212135, 2000-
309157, 2001-96897, 200
1-138627, JP-A-11-91242 and 8
-2087, 8-2090, 8-2091,
8-2093, 8-174992, 11-1
The embodiments disclosed in JP-A No. 92777, JP 2001-301314 A and the like can also be preferably used.

(Water-Soluble Resin) In the ink jet recording sheet of the present invention, it is preferable that the colorant receiving layer further contains a water-soluble resin. Examples of the water-soluble resin include polyvinyl alcohol resins having a hydroxy group as a hydrophilic structural unit [polyvinyl alcohol (PVA), acetoacetyl-modified polyvinyl alcohol, cation-modified polyvinyl alcohol, anion-modified polyvinyl alcohol, silanol-modified resin]. Polyvinyl alcohol, polyvinyl acetal, etc.], cellulosic resins [methyl cellulose (MC), ethyl cellulose (E
C), 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 (P
EG), polyvinyl ether (PVE), etc.], a resin having a carbamoyl group [polyacrylamide (PAA)
M), polyvinylpyrrolidone (PVP), polyacrylic acid hydrazide, etc.] and the like. Further, polyacrylic acid salts having a carboxyl group as a dissociative group, maleic acid resins, alginates, gelatins and the like can also be mentioned.

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.
No. 7-29479, Japanese Patent No. 2537827
No. 7, Japanese Patent Publication No. 7-75553, and Japanese Patent No. 2502998.
No. 3,053,231, JP-A-63-17617
No. 3, Japanese Patent No. 2604367, and Japanese Patent Laid-Open No. 7-27678.
7, JP-A-9-207425, JP-A-11-589.
41, JP-A-2000-135858, JP-A-2001
-205924, JP 2001-287444 A, JP 62-278080 A, JP 9-39373 A,
Japanese Patent No. 2750433, Japanese Patent Laid-Open No. 2000-158801
No. 2001-213045, 2001-3
28345, JP-A-8-324105, JP-A-11
Examples include those described in No. 348417 and the like. In addition, examples of water-soluble resins other than polyvinyl alcohol resins include compounds described in JP-A No. 11-165461, "0011" to "0014". These water-soluble resins may be used alone or in combination of two or more.

The content of the water-soluble resin of the present invention is preferably 9 to 40% by mass, more preferably 12 to 33% by mass, based on the total mass of the solid content of the colorant receiving layer.

Mainly constituting the colorant receiving layer of the present invention,
The aforementioned water-soluble resin and the above-mentioned fine particles may each be a single material, or may be a mixed system of a plurality of materials. From the viewpoint of maintaining transparency, the type of water-soluble resin combined with fine particles, especially silica fine particles, is important. When the vapor phase silica is used, the water-soluble resin is preferably a polyvinyl alcohol-based resin, of which a polyvinyl alcohol-based resin having a saponification degree of 70 to 100% is more preferable, and a saponification degree of 80 to 99.5. % Polyvinyl alcohol resin is particularly preferred.

The polyvinyl alcohol resin has a hydroxyl group in its structural unit. Since the hydroxyl group and the surface silanol group of the silica fine particles form a hydrogen bond, the secondary particles of the silica fine particles are used as a network chain unit. It becomes easy to form a three-dimensional network structure. It is considered that the formation of this three-dimensional network structure forms a colorant receiving layer having a porous structure with high porosity and sufficient strength. In ink jet recording, the porous coloring material-receiving layer obtained as described above rapidly absorbs ink by a capillary phenomenon,
It is possible to form dots having good circularity without causing ink bleeding.

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

<Content Ratio of Fine Particles to Water-Soluble Resin> Mass ratio of fine particles (x) to water-soluble resin (y) [PB ratio (x
/ Y)] has a great influence on the film structure and film strength of the colorant receiving layer. That is, as the mass content ratio [PB ratio] increases, the porosity, pore volume, and surface area (per unit mass) increase, but the density and strength tend to decrease.

The coloring material-receptive layer of the present invention has the above-mentioned mass content ratio [PB ratio (x / y)], which prevents reduction in film strength and cracking during drying due to the PB ratio being too large. In addition, when the PB ratio is too small, the voids are likely to be clogged with the resin, and the ink absorbency is prevented from being lowered due to the reduction of the void ratio.
5-10 are preferable.

Since the recording sheet may be stressed when passing through the transport system of the ink jet printer, the coloring material receiving layer must have sufficient film strength. Further, in the case of cutting into a sheet shape, it is necessary that the coloring material receiving layer has sufficient film strength in order to prevent cracking or peeling of the coloring material receiving layer. In consideration of these cases, the mass ratio (x / y) is more preferably 5 or less, while it is more preferably 2 or more from the viewpoint of ensuring high-speed ink absorbency in an inkjet printer.

For example, the vapor phase silica fine particles having an average primary particle diameter of 20 nm or less and the water-soluble resin are mixed in a mass ratio (x /
y) When a coating solution completely dispersed in an aqueous solution in 2 to 5 is coated on a support and the coating layer is dried, a three-dimensional network structure having secondary particles of silica fine particles as a network chain is formed, The average pore diameter is 30 nm or less, the porosity is 50 to 80%,
Pore specific volume 0.5ml / g or more, specific surface area 100m
It is possible to easily form a light-transmitting porous film having a weight ratio of ² / g or more.

(Crosslinking Agent) In the colorant receiving layer of the ink jet recording sheet of the present invention, the coating layer containing the fine particles and the water-soluble resin further contains a crosslinking agent capable of crosslinking the water-soluble resin. A preferred embodiment is a porous layer that is cured by a crosslinking reaction with a water-soluble resin.

Boron compounds are preferred for crosslinking the above water-soluble resins, especially polyvinyl alcohol resins. Examples of the boron compound include borax, boric acid, borate (eg orthoborate, InBO ₃ , ScBO ₃ , YB).
_{O 3, LaBO 3, Mg 3} (BO 3) 2, Co 3 (BO 3) 2, two borates _{(e.g., Mg 2 B 2 O 5,} Co 2 B 2 O 5), metaborate salts (e.g., LiBO ₂ , Ca (BO ₂ ) ₂ , NaBO ₂ , K
BO ₂ ), tetraborate (for example, Na ₂ B ₄ O ₇ · 10H
₂ O), pentaborate (eg KB ₅ O ₈ .4H ₂ O, Ca _{2
B 6 O 11 · 7H 2 O} , can be cited CsB ₅ O ₅₎ or the like. Among them, borax, boric acid, and borate are preferable, and boric acid is particularly preferable, because a crosslinking reaction can be rapidly caused.

As the cross-linking agent for the water-soluble resin, the following compounds other than the boron compound can be used. 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-triazine, 2,4-dichloro-6-S-
Active halogen compounds such as triazine / sodium salt; divinylsulfonic acid, 1,3-vinylsulfonyl-2-propanol, N, N'-ethylenebis (vinylsulfonylacetamide), 1,3,5-triacryloyl-hexahydro Active vinyl compounds such as -S-triazine; N such as dimethylolurea and methyloldimethylhydantoin
A methylol compound; a melamine resin (eg methylol melamine, alkylated methylol melamine); an epoxy resin;

Isocyanate compounds such as 1,6-hexamethylene diisocyanate; US Pat. No. 301
Nos. 7280 and 2983611; aziridine compounds; carboximide compounds described in U.S. Pat. No. 3,100,704; epoxy compounds such as glycerol triglycidyl ether; 1,6-hexamethylene-N, N '. -Ethyleneimino compounds such as bisethyleneurea; halogenated carboxaldehyde compounds such as mucochloric acid and mucophenoxycyclolic acid; dioxane compounds such as 2,3-dihydroxydioxane; titanium lactate, aluminum sulfate, chromium alum, potassium Examples thereof include metal-containing compounds such as alum, zirconyl acetate and chromium acetate, polyamine compounds such as tetraethylenepentamine, hydrazide compounds such as adipic acid dihydrazide, and low molecular weight compounds or polymers containing two or more oxazoline groups. The above-mentioned crosslinking agents may be used alone or in combination of two or more.

The cross-linking curing is carried out by adding a cross-linking agent to a coating liquid containing fine particles, a water-soluble resin and the like (hereinafter sometimes referred to as "coating liquid A") and / or the following basic solution, and
(1) When the coating liquid is applied to form a coating layer,
(2) in the middle of drying the coating layer formed by applying the coating liquid and before the coating layer shows a reduction rate drying, or (3) after drying the coating layer to form a coating film, In any of the above cases, it is preferable to apply a basic solution having a pH of 8 or more (hereinafter, may be referred to as “coating solution B”) to the coating layer. The cross-linking agent is preferably applied as described below using a boron compound as an example. That is, when the color material receiving layer is a layer obtained by cross-linking and curing the coating layer coated with the coating liquid (coating liquid A) containing the water-soluble resin containing fine particles and polyvinyl alcohol, the cross-linking and curing are described in (1) above. Simultaneously with the application of the coating liquid, (2) during the dry coating of the coating layer formed by applying the coating liquid, and before the coating layer shows a reduction rate drying, (3) drying the coating layer After forming the coating film, it is performed by applying a basic solution (coating liquid B) having a pH of 8 or more to the coating layer at any one of the following cases. The boron compound as a crosslinking agent may be contained in either the coating liquid A or the coating liquid B, or may be contained in both the coating liquid A and the coating liquid B. The amount of the cross-linking agent used is preferably from 1 to 50% by mass, more preferably from 5 to 40% by mass, based on the water-soluble resin.

(Mordant) In the present invention, it is preferable that a mordant is contained in the colorant-receiving layer in order to improve the water resistance and bleeding resistance of the formed image. The polymer having a primary, secondary or tertiary amino group used in the present invention also has a function as a mordant, but other mordants may be used. As such a mordant, a cationic polymer (cationic mordant) as an organic mordant, or an inorganic mordant is preferable, and by allowing the mordant to be present in the colorant-receptive layer, a liquid ink having an anionic dye as a colorant is obtained. Can interact with each other to stabilize the coloring material and improve water resistance and bleeding resistance over time.
The organic mordant and the inorganic mordant may be used alone, respectively, or the organic mordant and the inorganic mordant may be used in combination.

As the above cationic mordant, a polymer mordant having a primary to tertiary amino group or a quaternary ammonium group as a cationic group is preferably used, but a cationic non-polymer mordant is also used. can do. As the polymer mordant, a homopolymer of a monomer having a primary to tertiary amino group and a salt thereof, or a quaternary ammonium salt group (mordant monomer), or the mordant monomer and other monomer (hereinafter, Those obtained as a copolymer or a polycondensation polymer with "non-mordanting monomer") are preferable. Further, these polymer mordants can be used in any form of water-soluble polymer or water-dispersible latex particles.

Examples of the above-mentioned monomer (mordanting monomer) are trimethyl-p-vinylbenzylammonium chloride, trimethyl-m-vinylbenzylammonium chloride, triethyl-p-vinylbenzylammonium chloride, triethyl-m-vinylbenzylammonium. Chloride, N, N-dimethyl-N-ethyl-N-p-vinylbenzylammonium chloride,
N, N-diethyl-N-methyl-N-p-vinylbenzylammonium chloride, N, N-dimethyl-Nn
-Propyl-N-p-vinylbenzyl ammonium chloride, N, N-dimethyl-Nn-octyl-N-p
-Vinylbenzylammonium chloride, N, N-dimethyl-N-benzyl-Np-vinylbenzylammonium chloride, N, N-diethyl-N-benzyl-
N-p-vinylbenzylammonium chloride, N,
N-dimethyl-N- (4-methyl) benzyl-Np-
Vinylbenzylammonium chloride, N, N-dimethyl-N-phenyl-Np-vinylbenzylammonium chloride;

Trimethyl-p-vinylbenzylammonium bromide, trimethyl-m-vinylbenzylammonium bromide, trimethyl-p-vinylbenzylammonium sulfonate, trimethyl-m-vinylbenzylammonium sulfonate, trimethyl-p-vinylbenzylammonium acetate, trimethyl- m
-Vinylbenzyl ammonium 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 acetate;

N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth)
Acrylate, N, N-diethylaminopropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, Methyl chloride of N-diethylaminopropyl (meth) acrylamide,
Examples thereof include ethyl chloride, methyl bromide, ethyl bromide, quaternary compounds of methyl iodide or ethyl iodide, and sulfonates, alkylsulfonates, acetates or alkylcarboxylates of which anions are substituted.

Specifically, for example, monomethyldiallylammonium 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- (methacryloyl) Amino) ethylammonium chloride, trimethyl-
2- (acryloylamino) ethylammonium chloride, triethyl-2- (acryloylamino) ethylammonium chloride, trimethyl-3- (methacryloylamino) propylammonium chloride, triethyl-3- (methacryloylamino) propylammonium chloride, trimethyl-3- (Acryloylamino) propyl ammonium chloride, triethyl-
3- (acryloylamino) propyl ammonium 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- (acryloylamino) propyl ammonium acetate etc. can be mentioned. In addition, as the copolymerizable monomer, N-vinylimidazole, N-vinyl-2-methylimidazole and the like can also be mentioned.

The non-mordanting monomer does not contain a basic or cationic moiety such as a primary to tertiary amino group and its salt, or a quaternary ammonium base, and interacts with the dye in the ink jet ink. A monomer that does not show or has a substantially small interaction. Examples of the non-mordanting monomer include (meth) acrylic acid alkyl ester; (meth) acrylic acid cycloalkyl ester such as (meth) acrylic acid cyclohexyl; (meth) acrylic acid aryl ester such as (meth) acrylic acid phenyl; Aralkyl esters such as benzyl (meth) acrylate; aromatic vinyls such as styrene, vinyltoluene, α-methylstyrene; vinyl acetate, vinyl propionate,
Vinyl esters such as vinyl versatate; allyl esters such as allyl acetate; halogen-containing monomers such as vinylidene chloride and vinyl chloride; vinyl cyanide such as (meth) acrylonitrile; olefins such as ethylene and propylene. Can be mentioned.

As the above-mentioned (meth) acrylic acid alkyl ester, the alkyl moiety has a carbon number of 1 to 18 (meth)
Acrylic acid alkyl esters are preferable, for example, methyl (meth) acrylate, ethyl (meth) acrylate,
Propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate,
Examples include hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, and stearyl (meth) acrylate. Among them, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate and hydroxyethyl methacrylate are preferable. The above non-mordanting monomers can also be used alone or in combination of two or more.

Further, as the polymer mordant, polydiallyldimethylammonium chloride, polymethacryloyloxyethyl-β-hydroxyethyldimethylammonium chloride, polyethyleneimine, polyallylamine and its derivatives, polyamide-polyamine resin, cationized starch, dicyandiamide formalin condensation. , Dimethyl-2-hydroxypropylammonium salt polymer, polyamidine, polyvinylamine, dicyandiamide-kaotine resin typified by dicyandiamide-formalin polycondensate, dicyanamide-diaminetriamine polycondensation polyamine-based kaothin resin typified by polycondensate, epichlorohydrin- dimethylamine addition polymer, dimethyldiallylammonium phosphorus chloride -SO ₂ copolymers, diallylamine salt -SO Preferable ones are ₂ copolymers, (meth) acrylate-containing polymers having a quaternary ammonium salt group-substituted alkyl group in the ester moiety, and styryl type polymers having a quaternary ammonium salt group-substituted alkyl group.

The organic mordant used in the present invention has a weight average molecular weight of 10,000, particularly from the viewpoint of preventing aging blush.
Polyallylamine and its derivatives of 0 or less are preferable.

An inorganic mordant may be used as the mordant of the present invention, and 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, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, dislopro Mention may be made of salts or complexes of metals selected from sium, erbium, ytterbium, hafnium, tungsten and bismuth.

Specifically, for example, calcium acetate, calcium chloride, calcium formate, calcium sulfate, barium acetate, barium sulfate, barium phosphate, manganese chloride, manganese acetate, manganese formate dihydrate, and 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, aluminum chloride hexahydrate, ferrous bromide, ferrous chloride, ferric chloride, ferrous sulfate, ferric sulfate, zinc phenolsulfonate, odor Zinc oxide, 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, zirconium hydroxychloride, chromium acetate, chromium sulfate, magnesium sulfate, magnesium chloride hexahydrate 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 hydrate, gallium nitrate, germanium nitrate, strontium nitrate, yttrium acetate, yttrium chloride, Yttrium nitrate, indium nitrate, lanthanum nitrate, lanthanum chloride, lanthanum acetate, lanthanum benzoate, cerium chloride, cerium sulfate,
Examples thereof include cerium octylate, praseodymium nitrate, neodymium nitrate, samarium nitrate, europium nitrate, gadolinium nitrate, dysprosium nitrate, erbium nitrate, ytterbium nitrate, hafnium chloride and bismuth nitrate.

The inorganic mordant of the present invention is preferably an aluminum-containing compound, a titanium-containing compound, a zirconium-containing compound, or a metal compound (salt or complex) of Group IIIB series of the Periodic Table of the Elements. Mordant amount contained in the colorant receiving layer in the present invention is preferably from ^{0.01g / m 2 ~5g / m 2} , 0.1g / m 2 ~3g / m 2 is more preferable.

(Other Components) The ink jet recording sheet of the present invention may further contain various known additives such as acids, ultraviolet absorbers, antioxidants, fluorescent brighteners, monomers, polymerization initiation, if necessary. Agent, polymerization inhibitor, anti-bleeding agent,
An antiseptic, a viscosity stabilizer, a defoaming agent, a surfactant, an antistatic agent, a matting agent, an anti-curl agent, a water resistant agent and the like can be contained.

In the present invention, the coloring material receiving layer may contain an acid. By adding an acid, the surface pH of the colorant receiving layer is adjusted to 3 to 8, preferably 5 to 7.5. This is preferable because the yellowing resistance of the white background portion is improved. The surface pH is measured by the Japan Pulp and Paper Technology Association (J. TAPP
In the measurement of the surface PH defined in I), the measurement is performed by the A method (coating method). For example, the measurement can be carried out using a paper surface PH measurement set “type MPC” manufactured by Kyoritsu Riken Kagaku Kenkyusho, which corresponds to the method A.

Specific examples of acids include formic acid, acetic acid, glycolic acid, oxalic acid, propionic acid, malonic acid, succinic acid, adipic acid, maleic acid, malic acid, tartaric acid, citric acid, benzoic acid and phthalic acid. , Isophthalic acid, glutaric acid, gluconic acid, lactic acid, aspartic acid, glutamic acid, salicylic acid, salicylic acid metal salt (Zn, Al, C
a, Mg, etc.), methanesulfonic acid, itaconic acid, benzenesulfonic acid, toluenesulfonic acid, trifluoromethanesulfonic acid, styrenesulfonic acid, trifluoroacetic acid, barbituric acid, acrylic acid, methacrylic acid, cinnamic acid, 4 -Hydroxybenzoic acid, aminobenzoic acid, naphthalenedisulfonic acid, hydroxybenzenesulfonic acid,
Toluenesulfinic acid, benzenesulfinic acid, sulfanilic acid, sulfamic acid, α-resorcinic acid, β-resorcinic acid, γ-resorcinic acid, gallic acid, phloroglysin, sulfosalicylic acid, ascorbic acid, erythorbic acid, bisphenolic acid, hydrochloric acid, nitric acid , Sulfuric acid, phosphoric acid,
Examples thereof include polyphosphoric acid, boric acid, and boronic acid. The addition amount of these acids may be determined so that the surface PH of the color material receiving layer becomes 3 to 8. The above-mentioned acids are metal salts (for example, sodium, potassium, calcium, cesium, zinc, copper,
When used in the form of iron, aluminum, zirconium, lanthanum, yttrium, magnesium, strontium, cerium, etc.), or an amine salt (eg, ammonia, triethylamine, tributylamine, piperazine, 2-methylpiperazine, polyallylamine, etc.) Good.

In the present invention, it is preferable that the colorant receiving layer contains a preservative improving agent such as an ultraviolet absorber, an antioxidant and a bleeding inhibitor. As these ultraviolet absorbers, antioxidants, and anti-bleeding agents, alkylated phenol compounds (including hindered phenol compounds), alkylthiomethylphenol compounds, hydroquinone compounds, alkylated hydroquinone compounds, tocopherol compounds, thiodiphenyl ether compounds, 2 Compounds having the above thioether bond, bisphenol compounds, O-, N-
And an S-benzyl compound, a hydroxybenzyl compound,
Triazine compound, phosphonate compound, acylaminophenol compound, ester compound, amide compound, ascorbic acid, amine antioxidant, 2- (2-hydroxyphenyl) benzotriazole compound, 2-hydroxybenzophenone compound, acrylate, water-soluble or hydrophobic Metal salt, organometallic compound, metal complex, hindered amine compound (including TEMPO compound), 2- (2-
Hydroxyphenyl) 1,3,5-triazine compound, metal deactivator, phosphite compound, phosphonite compound, hydroxyamine compound, nitrone compound,
Peroxide scavenger, polyamide stabilizer, polyether compound, basic co-stabilizer, nucleating agent, benzofuranone compound, indolinone compound, phosphine compound, polyamine compound, thiourea compound, urea compound, hydrazito compound, amidine compound, sugar compound, Examples thereof include hydroxybenzoic acid compounds, dihydroxybenzoic acid compounds and trihydroxybenzoic acid compounds.

Among these, alkylated phenol compounds, compounds having two or more thioether bonds, bisphenol compounds, ascorbic acid, amine antioxidants, water-soluble or hydrophobic metal salts, organometallic compounds, metal complexes, Preferred are hindered amine compounds, hydroxyamine compounds, polyamine compounds, thiourea compounds, hydrazide compounds, hydroxybenzoic acid compounds, dihydroxybenzoic acid compounds, trihydroxybenzoic acid compounds and the like.

Specific examples of compounds are shown in Japanese Patent Application No. 2002-13.
005, JP-A-10-182621, and JP-A-2001.
-260519, Japanese Patent Publication No. 4-34953, Japanese Patent Publication 4
-34513, JP-A-11-170686, JP-B-4-34512, EP1138509, JP-A-60.
-67190, JP-A-7-276808, JP-A-20
01-94829, JP-A-47-10537, and JP-A-5-10537.
8-111942, 58-212844, 59
-19945, 59-46646, 59-10.
No. 9055, No. 63-53544, Japanese Patent Publication No. 36-10
No. 466, No. 42-26187, No. 48-30492.
No. 48-31255, No. 48-41572, No. 48-54965, No. 50-10726, U.S. Patent Nos. 2,719,086, 3,707,375, and 3,754,919. No. 4,220,711,

Japanese Patent Publication Nos. 45-4699 and 54-532
No. 4, European Published Patent Nos. 223739, 309.
No. 401, No. 309402, No. 310551, No. 310552, No. 459416, German Published Patent No. 3435443, JP-A-54-48535, No. 6
0-107384, 60-107383, 60
-125470, 60-125471, 60-
125472, 60-287485, 60-2
87486, 60-287487, 60-28
7488, 61-160287, 61-185.
No. 483, No. 61-211079, No. 62-1466.
No. 78, No. 62-146680, No. 62-14667.
No. 9, No. 62-282885, No. 62-262047.
No. 63-051174, No. 63-89877,
63-88380, 66-88381, 63
-113536,

63-163351 and 63-203.
372, 63-224989, 63-2512
No. 82, No. 63-267594, No. 63-18248.
4, JP-A-1-239382, and JP-A-2-2626.
No. 54, No. 2-71262, No. 3-121449,
No. 4-291685, No. 4-291688, No. 5-
61166, 5-1149449, 5-1886
No. 87, No. 5-188686, No. 5-110490
No. 5-1108437, No. 5-170361,
Examples thereof include those described in Japanese Patent Publications No. 48-43295, No. 48-33212, U.S. Pat. Nos. 4,814,262 and 4,980,275.

The other components may be used alone or in combination of two or more. These other components may be added after being made water-soluble, dispersed, polymer-dispersed, emulsified, oil-dropped, or encapsulated in microcapsules. In the inkjet recording sheet of the present invention,
The addition amount of the above-mentioned other components is 0.01 to 10 g.
/ M ² is preferred.

In the present invention, the coating liquid for the colorant receiving layer (coating liquid A) preferably contains a surfactant. As the surfactant, any of cationic, anionic, nonionic, amphoteric, fluorine-based, and silicon-based surfactants can be used. As the nonionic surfactant,
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 nonylphenyl ether, etc.),
Oxyethylene / oxypropylene block copolymers, sorbitan fatty acid esters (eg, sorbitan monolaurate, sorbitan monooleate, sorbitan trioleate), polyoxyethylene sorbitan fatty acid esters (eg, polyoxyethylene sorbitan monolaurate, polyoxy) Ethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, etc.), polyoxyethylene sorbitol fatty acid esters (eg, tetraoleic acid polyoxyethylene sorbit etc.), glycerin fatty acid esters (eg, glycerol monooleate), polyoxyethylene Glycerin fatty acid esters (polyoxyethylene glycerin monostearate, polyoxyethylene glycerin monooleate, etc.), Polyoxyethylene fatty acid esters (polyethylene glycol monolaurate, polyethylene glycol monooleate), polyoxyethylene alkylamine, acetylene glycols (e.g.,
2,4,7,9-Tetramethyl-5-decyne-4,7-
Examples thereof include diols, ethylene oxide adducts and propylene oxide adducts of the diols, and the like, among which polyoxyalkylene alkyl ethers are preferable. The nonionic surfactant can be used in the coating liquid A and the coating liquid B. Further, the nonionic surfactants may be used alone or in combination of two or more kinds.

Examples of the amphoteric surfactants include amino acid type, carboxyammonium betaine type, sulfolammonium betaine type, ammonium sulfate ester betaine type and imidazolium betaine type. For example, US Pat. No. 3,843,368. Specification, JP-A-5
9-49535, 63-236546,
What is described in Unexamined-Japanese-Patent No. 5-303205, 8-262742, 10-282619 etc. can be used conveniently. As the amphoteric surfactant,
Amino acid type amphoteric surfactants are preferable, and the amino acid type amphoteric surfactants are, for example, derivatized from amino acids (glycine, glutamic acid, histidic acid, etc.) as described in JP-A-5-303205. Specific examples thereof include N-aminoacyl acid having a long-chain acyl group introduced and salts thereof. The amphoteric surfactants may be used alone or in combination of two or more.

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

Examples of the above-mentioned fluorine-containing surfactant include compounds that are derived from an intermediate having a perfluoroalkyl group by a method such as electrolytic fluorination, telomerization, or oligomerization. Examples thereof include perfluoroalkyl sulfonates, perfluoroalkyl carboxylates, perfluoroalkyl ethylene oxide adducts, perfluoroalkyl trialkyl ammonium salts, perfluoroalkyl group-containing oligomers and perfluoroalkyl phosphates.

As the silicone-based surfactant, an organic group-modified silicone oil is preferable, which has 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 one end is modified. It can have a structure. 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 present invention is 0.001 to 2 with respect to the coating liquid for the colorant receiving layer (coating liquid A).
0% is preferable, and 0.01 to 1.0% is more preferable.
When two or more coating liquids for the color material receiving layer are used for coating, it is preferable to add a surfactant to each coating liquid.

In the present invention, the colorant receiving layer preferably contains a high boiling organic solvent for preventing curling. The high-boiling point organic solvent is an organic compound having a boiling point of 150 ° C. or higher under normal pressure and is a water-soluble or hydrophobic compound. These may be liquid or solid at room temperature, and may be low molecular weight or high molecular weight.
Specifically, aromatic carboxylic acid esters (eg, dibutyl phthalate, diphenyl phthalate, phenyl benzoate, etc.), aliphatic carboxylic acid esters (eg, dioctyl adipate, dibutyl sebacate, methyl stearate, dibutyl maleate) , Dibutyl fumarate, acetyl triethyl citrate, etc.), phosphates (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, glycerin, diethylene glycol monobutyl ether (DE
GMBE), triethylene glycol monobutyl ether, glycerin monomethyl ether, 1,2,3-butanetriol, 1,2,4-butanetriol, 1,
2,4-pentanetriol, 1,2,6-hexanetriol, thiodiglycol, triethanolamine,
Polyethylene glycol etc.), vegetable oil (eg soybean oil, sunflower oil etc.) and higher aliphatic carboxylic acid (eg linoleic acid, oleic acid etc.) and the like.

(Support) As the support of the present invention, both a transparent support made of a transparent material such as plastic and an opaque support made of an opaque material such as paper can be used.
In order to make the most of the transparency of the colorant receiving layer, it is preferable to use a transparent support or a highly glossy opaque support.

As a material which can be used for the transparent support, a material which is transparent and has a property of withstanding radiant heat when used in an OHP or a backlight display is preferable. Examples of the material include polyesters such as polyethylene terephthalate (PET); polysulfone,
Examples thereof include polyphenylene oxide, polyimide, polycarbonate and polyamide. Among them, polyesters are preferable, and polyethylene terephthalate is particularly preferable. The thickness of the transparent support is not particularly limited, but is preferably 50 to 200 μm from the viewpoint of easy handling.

As the highly glossy opaque support, one having a glossiness of 40% or more on the surface on which the colorant receiving layer is provided is preferable. The glossiness is JIS P-814.
It is a value obtained according to the method described in 2 (75-degree specular gloss test method for paper and paperboard). Specific examples include the following supports.

For example, high gloss paper supports such as art papers, coated papers, cast coated papers and baryta papers used for silver salt photographic supports; polyesters such as polyethylene terephthalate (PET); nitrocellulose. , Cellulose acetate, cellulose acetate such as cellulose acetate butyrate, plastic film such as polysulfone, polyphenylene oxide, polyimide, polycarbonate, polyamide, etc. were made opaque by containing a white pigment etc. (may be subjected to surface calendering treatment) High-gloss film; or a high-gloss film containing the above various paper supports, the above-mentioned transparent supports or white pigments, etc., provided with a polyolefin coating layer containing or not containing a white pigment. And a support or the like. A white pigment-containing expanded polyester film (for example, expanded PET in which polyolefin fine particles are contained and voids are formed by stretching) can also be preferably mentioned. Further, resin coated paper used for silver salt photographic printing paper is also suitable.

The thickness of the opaque support is not particularly limited, but it is preferably 50 to 300 μm from the viewpoint of handleability.

The surface of the support may be subjected to a corona discharge treatment, a glow discharge treatment, a flame treatment, an ultraviolet irradiation treatment or the like in order to improve the wetting property and the adhesiveness.

Next, the base paper used for the resin coated paper will be described in detail. The base paper is made from wood pulp as a main raw material, and if necessary, synthetic paper such as polypropylene, or synthetic fiber such as nylon or polyester is used in addition to wood pulp. Examples of the wood pulp include LBKP, LBSP, NBKP, NBS
Any of P, LDP, NDP, LUKP and NUKP can be used, but LBKP and NBS with a large amount of short fibers
It is preferable to use more P, LBSP, NDP, and LDP. However, the ratio of LBSP and / or LDP is preferably 10% by mass or more and 70% by mass or less.

As the above pulp, a chemical pulp containing few impurities (sulfate pulp or sulfite pulp) is preferably used,
Pulp that has been bleached to improve its whiteness is also useful.

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

The freeness of the pulp used for papermaking is as follows.
According to CSF regulations, 200 to 500 ml is preferable, and
The fiber length after beating is preferably 30 to 70% of the sum of the 24% mesh residual mass% and the 42 mesh residual mass% defined by JIS P-8207. The mass% of the 4-mesh residue is preferably 20 mass% or less.

The basis weight of the base paper is preferably 30 to 250 g, particularly preferably 50 to 200 g. The thickness of the base paper is preferably 40 to 250 μm. The base paper can be given a high smoothness by calendering at the papermaking stage or after the papermaking. Base paper density is 0.7-1.2g / m2 (J
ISP-8118) is common. Furthermore, the stiffness of the base paper is 2 under the conditions specified in JIS P-8143.
0 to 200 g is preferable.

A surface sizing agent may be applied to the surface of the base paper, and as the surface sizing agent, the same sizing agent as that which can be added to the base paper can be used. The pH of the base paper is JI
It is preferably 5 to 9 when measured by the hot water extraction method specified in SP-8113.

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

In particular, the polyethylene layer on the side of forming the colorant receiving layer contains rutile or anatase type titanium oxide, an optical brightening agent, and ultramarine blue added to polyethylene, as is widely used in photographic printing paper. However, those having improved opacity, whiteness and hue are preferred. Here, the content of titanium oxide is generally 3 to 3 with respect to polyethylene.
20 mass% is preferable and 4-13 mass% is more preferable. The thickness of the polyethylene layer is not particularly limited, but 10 to 50 μm is suitable for both the front and back layers. Further, an undercoat layer may be provided on the polyethylene layer in order to impart adhesion to the coloring material receiving layer. As the undercoat layer, aqueous polyester, gelatin and PVA are preferable. Further, the thickness of the undercoat layer is preferably 0.01 to 5 μm.

The polyethylene-coated paper can be used as a glossy paper, or when a polyethylene is melt-extruded on the surface of a base paper for coating, a so-called patterning treatment is performed to obtain a matte surface or a matte surface obtained by ordinary photographic printing paper. It is also possible to use those having a silk surface.

A back coat layer may be provided on the support, and the components that can be added to this back coat layer are:
Examples include white pigments, aqueous binders, and other components. Examples of the white pigment contained in the back coat layer include light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, and aluminum silicate. , Diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica,
Colloidal alumina, pseudo-boehmite, aluminum hydroxide, alumina, lithopone, zeolite, hydrohalloysite, magnesium carbonate, white inorganic pigments such as magnesium hydroxide, styrene plastic pigment, acrylic plastic pigment, polyethylene, microcapsule, urea resin, melamine Examples include organic pigments such as resins.

Examples of the aqueous binder used in the back coat layer include styrene / maleate copolymer, styrene / acrylate copolymer, polyvinyl alcohol, silanol-modified polyvinyl alcohol, starch,
Examples thereof include water-soluble polymers such as cationized starch, casein, gelatin, carboxymethyl cellulose, hydroxyethyl cellulose and polyvinylpyrrolidone, and water-dispersible polymers such as styrene butadiene latex and acrylic emulsion. Examples of other components contained in the back coat layer include a defoaming agent, a defoaming agent, a dye, a fluorescent brightening agent, a preservative, and a water resistance agent.

(Preparation of Inkjet Recording Sheet) For the coloring material receiving layer of the inkjet recording sheet of the present invention, for example, a coating solution A containing at least fine particles and a water-soluble resin is applied onto the surface of a support, and (1) Simultaneously with the coating, (2) during the drying of the coating layer formed by the coating and before the coating layer exhibits a rate of reduction drying, or (3) after drying the coating layer to form a coating film. Is preferably formed by a method of applying a coating solution B having a pH of 8 or more containing a polymer having at least an amino group, and then crosslinking-curing the coating layer provided with the coating solution B. Here, the compound represented by the formula (1) of the present invention is preferably contained in at least one of the coating liquid A and the coating liquid B,
Alternatively, a third coating liquid (hereinafter, sometimes referred to as "coating liquid C") other than this may be applied. Among these, it is more preferable that the coating liquid A contains a silane coupling agent such as the compound represented by the formula (1). Further, a cross-linking agent capable of cross-linking the water-soluble resin is also preferably contained in at least one of the coating liquid A, the coating liquid B and the coating liquid C. It is preferable to provide the color material-receptive layer cross-linked and cured in this way from the viewpoints of ink absorbency and prevention of film cracking.

According to the above-described method, since the mordant is present in a large amount in a predetermined portion of the color material receiving layer, the ink jet color material is sufficiently mordant, and the color density, the aging blur, the printing area gloss, the characters after printing and the like. It is preferable because the water resistance and ozone resistance of the image are improved. A part of the mordant may be contained in the layer initially provided on the support, and in this case, the mordant applied later may be the same or different.

In the present invention, the coating liquid for the colorant receiving layer (coating liquid A) containing at least fine particles (for example, vapor phase silica) and a water-soluble resin (for example, polyvinyl alcohol) is as follows, for example. Can be prepared. That is, fine particles such as silica in the vapor phase method and a dispersant are added to water (for example, silica fine particles in water are 10 to 20% by mass), and a high-speed rotating wet colloid mill (for example, "M Technique Co., Ltd." CLEARMIX "), for example, 10000 rpm (preferably 5000 to 20000)
After being dispersed for 20 minutes (preferably 10 to 30 minutes) under the condition of high speed rotation of (rpm), a polyvinyl alcohol (PVA) aqueous solution (for example, PVA having a mass about 1/3 of that of the vapor phase silica) is used. Is added, and the dispersion is carried out under the same rotation conditions as described above. In order to impart stability to the coating liquid, it is preferable to adjust the pH to about 9.2 with aqueous ammonia or the like, or to use a dispersant. The obtained coating liquid is in a uniform sol state, and a porous coloring material-receptive layer having a three-dimensional network structure can be formed by coating it on a support by the following coating method and drying it. .

Further, for the preparation of the aqueous dispersion comprising the above vapor phase silica and the dispersant, an aqueous dispersion of vapor phase silica may be prepared in advance and the aqueous dispersion may be added to the aqueous dispersant solution. The aqueous dispersant solution may be added to the aqueous silica dispersion of the vapor phase method, or may be mixed at the same time. Further, instead of the aqueous dispersion of vapor-phase method silica, powdery vapor-phase method silica may be added to the dispersant aqueous solution as described above. After mixing the vapor-phase method silica and the dispersant described above, the mixture is atomized with a disperser to obtain an aqueous dispersion having an average particle diameter of 50 to 300 nm. As the disperser used for obtaining the aqueous dispersion, various conventionally known dispersers such as a high-speed rotation disperser, a medium stirring type disperser (ball mill, sand mill, etc.), an ultrasonic disperser, a colloid mill disperser, a high-pressure disperser, etc. Although a disperser can be used, a medium stirring type disperser, a colloid mill disperser or a high pressure disperser is preferable from the viewpoint of efficiently dispersing the lump-shaped fine particles to be formed.

Further, water, an organic solvent, or a mixed solvent thereof can be used as a solvent in each step. Examples of the organic solvent that can be used for this coating include alcohols such as methanol, ethanol, n-propanol, i-propanol and methoxypropanol, ketones such as acetone and methyl ethyl ketone, tetrahydrofuran, acetonitrile, ethyl acetate, toluene and the like. To be

A dispersant may be added to improve the dispersibility of the coating solution. As the dispersant, the above-mentioned chaotic polymer is preferably used. The amount of the dispersant added to the fine particles is preferably 0.1% to 30%, more preferably 1% to 10%.

The coating of the coating liquid for the colorant-receiving layer is carried out, for example, by
It can be performed by 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, and a bar coater.

The coating liquid B is applied to the coating layer at the same time as or after the coating of the coating liquid for the color material receiving layer (coating liquid A). It may be applied before the specific drying rate is exhibited. That is, after the coating liquid for the color material receiving layer (coating liquid A) is coated, the coating liquid B is introduced while the coating layer shows a constant rate of drying, so that it is suitably manufactured. The coating liquid B may contain a mordant.

The term "before the coating layer starts to exhibit a decreasing rate of drying" usually means a process for a few minutes immediately after the coating liquid for the color material receiving layer is applied. The phenomenon of "constant rate of drying" in which the content of the solvent (dispersion medium) in the applied coating layer decreases in proportion to time is shown. Regarding the time indicating this "constant rate of drying", see, for example, Chemical Engineering Handbook (pages 707 to 712, published by Maruzen Co., Ltd., Showa 5).
October 25, 5).

As described above, after coating the coating solution A, the coating layer is dried until it exhibits a rate of reduction drying, and this drying is generally at 40 to 180 ° C. for 0.5 to 10 minutes (preferably Is performed for 0.5 to 5 minutes). The drying time naturally depends on the coating amount, but the above range is usually appropriate.

As the method of applying the above first coating layer before the rate of drying rate is decreased, the coating solution B is further coated on the coating layer, the method of spraying by a method such as spraying, the coating method. Examples include a method of immersing the support having the coating layer formed therein in the liquid B.

In the above method, the coating method for applying the coating liquid B is, for example, a curtain flow coater,
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 used. However, it is preferable to use a method, such as an extrusion die coater, a curtain flow coater, or a bar coater, in which the coater does not directly contact the already formed first coating layer.

After applying the coating liquid B, it is generally 40 to 180.
Drying and curing are carried out by heating at 0 ° C. for 0.5 to 30 minutes. Above all, it is preferable to heat at 40 to 150 ° C. for 1 to 20 minutes.

When the coating liquid B is applied at the same time as the coating liquid for the colorant-receptive layer (coating liquid A) is applied, the coating liquids A and B are made to come into contact with the support. A colorant receiving layer can be formed by simultaneous coating (multilayer coating) on a support, followed by drying and curing.

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

When the above simultaneous coating (multilayer coating) is carried out by, for example, an extrusion die coater,
The two types of coating liquids discharged at the same time are layered in the vicinity of the discharge port of the extrusion die coater, that is, before being transferred onto the support, and in that state, they are layered on the support. The two layers of coating liquid that have been overlaid before coating tend to undergo a cross-linking reaction at the interface between the two liquids when they are transferred to the support. As a result, the viscosity tends to increase, which may hinder the coating operation. Therefore, in the simultaneous coating as described above, it is preferable to coat the coating liquid A and the coating liquid B together with the barrier layer liquid (intermediate layer liquid) for simultaneous triple layer coating.

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

After the color material receiving layer is formed on the support, a surface treatment such as a super calender or a gloss calender is carried out by calendering under heat and pressure through the roll nip to obtain surface smoothness, glossiness and transparency. And it is possible to improve the coating film strength. However, the calendering process may cause a decrease in the porosity (that is, the ink absorbency may decrease), and therefore, it is necessary to set conditions under which the decrease in the porosity is small.

The roll temperature for calendering treatment is preferably 30 to 150 ° C., and 40 to 100 ° C.
C is more preferred. Further, the linear pressure between the rolls during the calendar treatment is preferably 50 to 400 kg / cm,
100 to 200 kg / cm is more preferable.

In the case of ink jet recording, the layer thickness of the color material receiving layer needs to be determined in relation to the porosity in the layer, since it is necessary to have an absorption capacity enough to absorb all the droplets. is there. For example, if the ink amount is 8 nL / mm ²
If the porosity is 60%, the layer thickness is about 15 μm.
The above film is required. Considering this point, in the case of inkjet recording, the layer thickness of the colorant receiving layer is 1
0 to 50 μm is preferable.

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

The colorant-receiving layer preferably has excellent transparency. As a guideline, the haze value when the colorant-receiving layer is formed on a transparent film support is 30.
% Or less, and more preferably 20% or less. The haze value is a haze meter (HG
M-2DP: It can be measured using Suga Test Instruments Co., Ltd.

A fine polymer particle dispersion may be added to the constituent layers of the ink jet recording sheet of the present invention (for example, a color material receiving layer or a back layer). This polymer fine particle dispersion is used for the purpose of improving physical properties of the film such as dimensional stabilization, curl prevention, adhesion prevention, and film cracking prevention. For the polymer fine particle dispersion, see Japanese Patent Laid-Open No.
2-245258, 62-1316648, 6
It is described in each publication of 2-110066. When a polymer fine particle dispersion having a low glass transition temperature (40 ° C. or lower) is added to the layer containing the mordant, cracking or curling of the layer can be prevented. Further, even if a polymer fine particle dispersion having a high glass transition temperature is added to the back layer,
Curling can be prevented. Further, the ink jet recording sheet of the present invention is described in JP-A-10-81064,
10-119423, 10-157277, 10-217601, 11-348409, JP 2001-138621A, 2000-43401.
Issue 2000-212135 Issue 2000-309
157, 2001-96897, 2001-1
38627, JP-A Nos. 11-91242 and 8-20.
No. 87, No. 8-2090, No. 8-2091, No. 8-
It can also be produced by the method described in each publication of No. 2093.

[0129]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples. In addition, "parts" and "%" in Examples represent "parts by mass" and "mass%" unless otherwise specified, and "average molecular weight".
"Polymerization degree" means "mass average molecular weight" and "mass average polymerization degree".

(Preparation of Support) Wood pulp consisting of 100 parts of LBKP was beaten with a double disc refiner to a Canadian freeness of 300 ml, and 0.5 part of epoxidized behenic acid amide, 1.0 part of anionic polyacrylamide, and 0.1 part of polyamide polyamine epichlorohydrin. 1 part and 0.5 parts of cationic polyacrylamide were added at an absolutely dry mass ratio to the pulp, and weighed with a Fourdrinier paper machine to make 170 g / m ² of base paper.

To adjust the surface size of the above-mentioned base paper, 0.04% of a fluorescent whitening agent (“Whitex BB” manufactured by Sumitomo Chemical Co., Ltd.) was added to a 4% aqueous solution of polyvinyl alcohol.
The base paper was added and impregnated in the above-mentioned base paper so as to be 0.5 g / m 2 in terms of absolute dry weight, dried and then calendered to obtain a base paper adjusted to a density of 1.05 g / cc. It was

The wire surface (back surface) side of the obtained base paper was subjected to corona discharge treatment, and then high density polyethylene was coated to a thickness of 19 μm using a melt extruder, and a resin layer composed of a matte surface was formed. Was formed (hereinafter, the resin layer surface is referred to as “back surface”). Corona discharge treatment is further applied to the resin layer on the back side, and thereafter, aluminum oxide (“Alumina sol 100” manufactured by Nissan Chemical Industries, Ltd.) and silicon dioxide (manufactured by Nissan Chemical Industries, Ltd.) are used as antistatic agents. Snowtex O ") was dispersed in water in a mass ratio of 1: 2, and the dispersion was applied so that the dry mass would be 0.2 g / m ² .

Further, after the corona discharge treatment was applied to the felt surface (surface) side where the resin layer was not provided, anatase type titanium dioxide 10%, a trace amount of ultramarine blue, and a fluorescent brightening agent 0.01% ( Polyethylene) and low density polyethylene with MFR (melt flow rate) 3.8 are extruded using a melt extruder to a thickness of 29 μm, and a high-gloss thermoplastic resin layer is provided on the surface side of the base paper. (Hereinafter, this high-gloss surface is referred to as "front surface") to form a support.

[Example 1] (Preparation of coating liquid A1 for colorant receiving layer) [PAS-M-1] with fine particles of vapor phase method silica in the following composition, ion-exchanged water, silane coupling agent and
And mixed with a high-speed rotary colloid mill (“Clearmix” manufactured by M Technique Co., Ltd.) to rotate at a rotation speed of
After dispersing at 000 rpm for 20 minutes, a solution containing the following polyvinyl alcohol, boric acid, polyoxyethylene lauryl ether and ion-exchanged water is added,
Further, the dispersion was carried out again at a rotation speed of 10,000 rpm for 20 minutes to prepare a coating material A1 for the colorant receiving layer. The mass ratio of the silica fine particles and the water-soluble resin (PB ratio = /) is
The pH of the coating material A1 for the colorant receiving layer is 4.5.
It showed acidity at 8.

[0135]   <Composition of coating liquid A1 for colorant receiving layer> Gas phase method silica fine particles (inorganic fine particles) 10.0 parts   ("Leoseal QS30" manufactured by Tokuyama Corp., average primary particle diameter 7 nm) Deionized water 51.7 parts Silane coupling agent (Compound 1-4) (20% methanol solution) 1.0 part "PAS-M-1" (60% aqueous solution) 0.83 parts   (Dispersant, manufactured by Nitto Boseki Co., Ltd.) Polyvinyl alcohol (water-soluble resin) 8% aqueous solution 27.8 parts   ("PVA124" manufactured by Kuraray Co., saponification degree 98.5%, polymerization degree 2400) Boric acid (crosslinking agent) 0.4 parts Polyoxyethylene lauryl ether (surfactant 1.2 parts ("Emulgen 109P" (10% aqueous solution, manufactured by Kao Corporation, HLB value 13.6) Deionized water 33.0 parts

(Preparation of Inkjet Recording Sheet) After the front surface of the support was subjected to corona discharge treatment, the colorant receiving layer coating solution A1 obtained above was applied to the front surface of the support by an extrusion die coater. 200m using
A coating amount of 1 / m ² was applied (coating step), and the coating layer was dried at 80 ° C. (air velocity 3 to 8 m / sec) until the solid concentration of the coating layer reached 20%. This coating layer exhibited a constant drying rate during this period. Immediately after that, it was immersed in a mordant solution B1 having the following composition for 30 seconds, and 20 g /
m ² attached (step of applying mordant solution), and further 8
It was dried at 0 ° C. for 10 minutes (drying step). As a result, an inkjet recording sheet (1) of the present invention provided with a coloring material receiving layer having a dry film thickness of 32 μm was produced.

[0137]   <Composition of mordant coating liquid B1> Boric acid (crosslinking agent) 0.65 parts Polyallylamine "PAA-10C" 10% aqueous solution 25 parts   (Mordant, manufactured by Nittobo Co., Ltd.) Deionized water 59.7 parts Ammonium chloride (surface pH adjuster) 0.8 parts Polyoxyethylene lauryl ether (surfactant) 10 parts   ("Emulgen 109P" manufactured by Kao Corporation, 2% aqueous solution, HLB value 13.6) MegaFac “F1405” 10% aqueous solution 2.0 parts   (Fluorine-based surfactant manufactured by Dainippon Ink and Chemicals, Inc.)

[Examples 2 to 5] Ink jet recording sheets of Examples 2 to 5 were prepared in the same manner as in Example 1 except that the silane coupling agent 1-4 of Example 1 was changed to that shown in Table 1. It was made.

Example 6 <Synthesis Example 1> 2.7 parts of acrylonitrile was added to 114.0 parts of a 10% aqueous solution of polyallylamine (“PAA-10C” manufactured by Nitto Boseki Co., Ltd.), and the mixture was stirred at room temperature for 8 hours. 10% of polyallylamine derivative 1 (compound obtained by cyanoethylating a part of amino groups of polyallylamine) by adjusting the concentration by adding water and stirring.
An aqueous solution was obtained.

An ink jet recording sheet of Example 6 was prepared in the same manner as in Example 1 except that the mordant coating solution B1 of Example 1 was changed to the mordant coating solution B2.

[0141] [Composition of mordant coating liquid B2] Boric acid (crosslinking agent) 2.5 parts Ion-exchanged water 69.5 parts Polyallylamine derivative 1 10% aqueous solution 25 parts Polyoxyethylene lauryl ether 2 parts Ammonium chloride 1 part

[Embodiment 7] In the composition of <Coating liquid A1 for coloring material receiving layer> of Embodiment 1, basic aluminum chloride (Al ₂ (OH) ₅ Cl, manufactured by Taki Chemical Co., Ltd.
# 1000 ", 40% aqueous solution) was added, and an ink jet recording sheet of Example 7 was prepared in the same manner as in Example 1.

[Embodiment 8] In <Composition of coating material A1 for coloring material receiving layer> of Embodiment 1, zirconyl acetate (30
% Aqueous solution), and an ink jet recording sheet of Example 8 was prepared in the same manner as in Example 1 except that 0.3 part was added.

Example 9 The same procedure as in Example 1 was carried out except that the gas phase method silica fine particles were changed to the gas phase method alumina fine particles in <Color material receiving layer coating liquid A1> of Example 1. Inkjet recording sheet No. 9 was produced.

[Comparative Example 1] Ink jet recording of Comparative Example 1 was carried out in the same manner as in Example 1 except that the coating material A1 for coloring material receiving layer of Example 1 was changed to the coating fluid A2 for coloring material receiving layer described below. A sheet was prepared.

[0146] <Composition of coating liquid A2 for colorant receiving layer> Gas phase method silica fine particles (inorganic fine particles) 10.0 parts   ("Leoseal QS30" manufactured by Tokuyama Corp., average primary particle diameter 7 nm) Deionized water 51.7 parts "PAS-M-1" (60% aqueous solution) 0.83 parts   (Dispersant, manufactured by Nitto Boseki Co., Ltd.) Polyvinyl alcohol (water-soluble resin) 8% aqueous solution 27.8 parts   ("PVA124" manufactured by Kuraray Co., saponification degree 98.5%, polymerization degree 2400) Boric acid (crosslinking agent) 0.4 parts Polyoxyethylene lauryl ether (surfactant) 1.2 parts ("Emulgen 109P" (10% aqueous solution, manufactured by Kao Corporation, HLB value 13.6) Deionized water 33.0 parts

[Comparative Example 2] In <Coating Liquid A1 for Coloring Material Receiving Layer> of Example 1, except that the silane coupling agent 1-4 was changed to phenyltrimethoxysilane.
An ink jet recording sheet of Comparative Example 2 was produced in the same manner as in.

[Comparative Example 3] In <Coating Liquid A1 for Coloring Material Receiving Layer> of Example 1, except that silane coupling agent 1-4 was changed to octyl glycidyl ether, Example 1 was used.
An ink jet recording sheet of Comparative Example 3 was produced in the same manner as in.

[Comparative Example 4] <Mordant coating liquid B of Example 1>
An ink jet recording sheet of Comparative Example 4 was produced in the same manner as in Example 1 except that <1> was changed to <Mordant coating liquid B3>.

[0150] <Composition of mordant coating liquid B3> Boric acid (crosslinking agent) 2.5 parts Ion-exchanged water 69.5 parts Poly (N- (vinylbenzyl) triethylammonium chloride                     (10% aqueous solution) 25 parts Polyoxyethylene lauryl ether 2 parts Ammonium chloride 1 part

(Evaluation Test) The following evaluation tests were carried out on each of the ink jet recording sheet of the present invention and the comparative ink jet recording sheet obtained as described above. The test results are shown in Table 1 below.

<Printing Density> A black solid image is printed on each inkjet recording sheet using an inkjet printer (“PM-900C” manufactured by Seiko Epson Corp.), and the printing screen is left after standing for 3 hours. The reflection density was measured with a Macbeth reflection densitometer. The case where the reflection density was 2.4 or more was evaluated as A, the range of 2.0 to less than 2.4 was evaluated as B, and the case of less than 2.0 was evaluated as C.

<Time-dependent rainbow-1> Inkjet printer (“PM-900” manufactured by Seiko Epson Corporation)
C ”) was used to print a grid-like linear pattern (line width 0.28 mm) in which magenta and black ink were adjacent to each other on each inkjet recording sheet. After leaving for 3 hours after printing, it was stored in a thermo-hygrostat at a temperature of 40 ° C. and a relative humidity of 90% for 3 days, and the line width of the black portion was measured and evaluated according to the following criteria. When the line width is less than 0.30 mm and the generation of bleeding with time is hardly observed, A is given. When the line width is less than 0.30 to 0.35 mm, and when some bleeding with time is observed, B is given. The case where marked bleeding with time was observed at 0.35 mm or more was evaluated as C.

<Time-lapse rainbow-2> Inkjet printer (“PM-900” manufactured by Seiko Epson Corporation)
C ”) was used to print a grid-like linear pattern (line width 0.28 mm) in which magenta and black ink were adjacent to each other on each inkjet recording sheet. Immediately after printing, seal the recording sheet in a clear file and set the temperature to 35
The sample was stored in a thermo-hygrostat at 85 ° C. and a relative humidity of 85% for 3 days, and the line width of the black portion was measured and evaluated according to the following criteria.
When the line width is less than 0.30 mm and almost no occurrence of bleeding with time is observed, A is set, and the line width is 0.30 to 0.35 mm.
When less than 0.1%, some bleeding with time was observed, and B was evaluated when the line width was 0.35 mm or more, and bleeding with time was noticeable.

<Light resistance> After printing a solid image of magenta on each inkjet recording sheet using an inkjet printer ("PM-900C" manufactured by Seiko Epson Corporation), ultraviolet rays in the wavelength range of 365 nm or less Xenon Wea through a filter that cuts
Using a ther-ometer Ci65A (manufactured by ATLAS), the lamp was lit for 3.8 hours under environmental conditions of temperature 25 ° C and relative humidity 32%, and then the lamp was extinguished at a temperature of 20 ° C and relative humidity 91%. A cycle of standing for 1 hour under environmental conditions was performed for 168 hours. The image density of each color before and after this test was measured using a reflection densitometer (Xrit
"Xrite 938" manufactured by e. Co., Ltd., and the residual ratio of each color density was calculated. The residual rate was evaluated as A when the residual rate was 90% or more, B when the residual rate was 80 to less than 90%, C when the residual rate was 70 to less than 80%, and D when the residual rate was less than 70%.

<Ozone resistance> A solid image of cyan was printed on each ink jet recording sheet using an ink jet printer ("PM-900C" manufactured by Seiko Epson Corp.), and the ozone concentration was 2.5 ppm. It was stored in the environment for 24 hours. The cyan densities before and after storage were measured using a reflection densitometer (“Xrite 9 manufactured by Xrite”).
38 "), and the residual ratio of the cyan density was calculated. The residual rate was evaluated as A when the residual rate was 80% or more, B when the residual rate was 70 to less than 80%, C when the residual rate was 60 to less than 70%, and D when the residual rate was less than 60%.

[0157]

[Table 1]

From the results of Table 1 above, ink jet recording sheets containing the polymer of the present invention (Examples 1 to 8)
Was found to be an inkjet recording sheet in which bleeding over time was suppressed. Further, it was found that the recording sheet has a high density residual ratio of the formed image even under a high-concentration ozone environment and after a cycle test of irradiation with xenon and leaving it in a high humidity, and excellent in storage stability. Further, the ink jet recording sheet of the present invention was excellent in all of glossiness, ink absorption speed, image area density and water resistance. On the other hand, the ink jet recording sheet containing a polymer having no group capable of binding to the inorganic fine particles at the end has a low image density after printing, and the ink jet recording sheet containing a cationic polymer has light resistance. It was not sufficient, and bleeding over time occurred.

[0159]

The ink jet recording sheet of the present invention is
The image area has excellent light resistance and gas resistance, and even when stored in a high temperature and high humidity environment for a long time, blurring with time does not occur.

Continued front page    F-term (reference) 2C056 EA13 FC06                 2H086 BA01 BA15 BA31 BA33 BA35                       BA37                 4D075 BB24Y BB68Y BB96Y CA35                       CA38 CB02 CB04 DA06 DB18                       DB31 DB48 DB53 DC27 EA06                       EB12 EB22 EB32 EB33 EB39                       EB44 EB55 EC01 EC02 EC03                       EC45

Claims (10)

[Claims] 1. An ink jet recording sheet having a color material receiving layer on a support, wherein the color material receiving layer comprises inorganic fine particles, a polymer having a primary, secondary or tertiary amino group, and the amino group. An ink jet recording sheet comprising a silane coupling agent having a functional group capable of forming a bond by reaction with a group. 2. The ink jet recording sheet according to claim 1, wherein the silane coupling agent is represented by the following general formula (1). [Chemical 1] [In the formula, X ¹ is an alkoxy group having 1 to 8 carbon atoms or an aryloxy group, and X ² is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms which may contain a saturated or unsaturated cyclic structure, a carbon atom Represents an alkoxy group or an aryloxy group of the formulas 1 to 8, and Y represents an (n + 1) -valent linking group which may have a substituent or may have a heteroatom interposed. R represents a group capable of forming a covalent bond by reaction with a primary, secondary or tertiary amino group. n is an integer from 1 to 3, m is 1 or 2] 3. The ink jet recording sheet according to claim 1, wherein the polymer having an amino group is one kind or two or more kinds selected from polyallylamine, polyvinylamine, polyethyleneimine and derivatives thereof. 4. The ink jet recording sheet according to claim 2, wherein R in the general formula (1) is an epoxy group. 5. The inorganic fine particles are one kind or two or more kinds selected from silica fine particles, alumina fine particles, and pseudo-boehmite, and any one of claims 1 to 4 is characterized.
Ink jet recording sheet according to the item. 6. The ink jet recording sheet according to claim 1, wherein the coloring material receiving layer further contains a water-soluble resin. 7. The water-soluble resin is a polyvinyl alcohol resin, a cellulose resin, a resin having an ether bond,
The ink jet recording sheet according to claim 6, which is one or more selected from a resin having a carbamoyl group, a resin having a carboxyl group and gelatins. 8. The color material-receptive layer further contains a cross-linking agent capable of cross-linking the water-soluble resin.
The inkjet recording sheet described above. 9. A coating layer which is formed by coating a coating liquid A containing fine particles and a water-soluble resin on the surface of a support to form a coloring material receiving layer (1) at the same time as the coating (2). Of the primary, secondary or tertiary amino group either before the coating layer shows a rate-reduced drying or (3) after the coating layer is dried to form a coating film. Obtained by applying a coating liquid B containing the polymer having a silane coupling agent, and adding a silane coupling agent to at least one of the coating liquid A, the coating liquid B, and the coating liquid C different from the coating liquids A and B. 9. The inkjet recording sheet according to claim 1, which is obtained by applying the sheet. 10. The inkjet recording according to claim 9, wherein a crosslinking agent is further added to at least one of the coating liquids A, B and C to make the coating liquid B a basic solution having a pH of 8 or more. Sheet.