JPH10181190A - Ink jet recording medium and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent thickening of coating liquid and to obtain excellent glossiness, ink absorptivity, printing density and moisture and water resistance after printing by comminuting and dispersing aggregate pigment of pigment-containing coating liquid coating or impregnating a support in cationic resin-containing liquid, and forming specific aggregate mean particle size or less. SOLUTION: The ink jet recording medium coating or impregnating a support with pigment-containing coating liquid contains pigment obtained by comminuting and dispersing aggregate pigment in cation-containing liquid and comminuting it to mean particle size of 500nm or less. Uniform dispersion liquid is obtained by, for example, comminuting aggregate of silica of about 1 to 50μm by mechanical force, adding cationic resin before forming colloidal fine particle dispersion liquid, dispersing together with the aggregate such as silica, and then comminuting by the force. The dispersion liquid has satisfactory dispersing stability, coating suitability, excellent glossiness, printing density, and moisture and water resistance after printing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording medium, and more particularly to an ink jet recording medium having excellent gloss, ink absorbency, print density, water resistance, and the like, and a method for producing the same.

[0002]

2. Description of the Related Art An ink jet recording system is a system in which ink droplets ejected from a nozzle at a high speed are adhered to a recording material for recording, and has features such as easy full-color printing and low printing noise. . In this method, since the ink used contains a large amount of solvent, it is necessary to use a large amount of ink in order to obtain a high recording density. In addition, since the ink droplets are continuously ejected, the next droplet is ejected before the first droplet is absorbed, which is likely to cause a disadvantage that the ink droplets are fused and ink dots are joined. Therefore, the recording medium used in the ink jet recording method has a high print dot density, a bright and vivid color tone, and has a high ink absorption, and does not have ink bleeding even when the print dots overlap. Etc. are required. In recent years, in response to the rapid spread of inkjet printers, in the printing field, high-gloss photographic prints have been required for various publications and packaging applications. In particular, in the case of color recording, the need for a film or coated paper type is high in terms of ink acceptability such as dot shape (circular shape), dot sharpness, ink absorption, fixing speed, and ink absorption capacity. .

[0003] Since general ink-jet inks are water-soluble, they suffer from poor moisture and water resistance after printing.
In general, a cationic resin is blended in paper or a recording layer for the purpose of improving moisture resistance and water resistance. For example, Tokuhei 2
As disclosed in JP-035673A and the like, there is a report of improving moisture resistance and water resistance after printing by filling a pigment or a cationic resin into an ink jet recording paper and fixing an anionic dye in the ink. Further, there is a coated paper provided with a coating layer containing a pigment such as silica or alumina in order to increase the print quality (control of dot sharpness, etc.) and print density of the ink jet recording paper (for example: Japanese Patent Application JP-A-7-260198). However, these coated papers are generally composed of pigments of micron order, a cationic resin and an adhesive (binder) as main components, and the presence of the pigment allows the ink to be absorbed.
The dye in the absorbed ink is fixed by the cationic resin, but the pigment used has a large particle size, transparency is not always sufficient, the surface is easily rough, high gloss,
It was difficult to obtain an ink jet recording medium having a high printing density.

[0004]

For the purpose of improving gloss and print density, the present inventors pulverized fine particles such as silica having a micron order by a mechanical dispersion method, and prepared colloidal particles having a size of 500 nm or less. Japanese Patent Application Laid-Open No. Hei 8-102494), and it has been clarified that an ink jet recording medium having high gloss and high print density can be obtained by using the same. However, since colloidal particles such as silica have an anionic property, they have no fixing power to dyes as they are, and have a defect that moisture resistance and water resistance after printing are inferior. On the other hand, when a cationic resin is added, the viscosity increases, and the transparency and the surface smoothness may be significantly reduced. Also,
When a cationic resin is added, the coating liquid thickens, and there is a problem that coating becomes difficult. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide an ink jet recording medium that is more excellent in glossiness, ink absorbency, print density, and moisture resistance and water resistance after printing.

[0005]

The present invention includes, but is not limited to, the following aspects. [1] An ink jet recording material obtained by coating or impregnating a support with a pigment-containing coating liquid, wherein the coating liquid is obtained by pulverizing and dispersing an aggregate pigment in a cationic resin-containing liquid to have an average aggregate particle diameter of 500 nm or less. An ink-jet recording material, which is a coating liquid containing a pigment. [2] The ink jet recording medium according to [1], wherein the cationic resin-containing liquid further contains a water-soluble resin. [3] The ink jet recording material according to [1] or [2], wherein the aggregate pigment contains amorphous silica. [4] In the method for producing an ink jet recording medium provided with a recording layer on a support, at least one recording layer contains a pigment, and after being coated and formed on a molding surface, is formed on a support (or another When the recording layer is already provided on the support, the method is a method for producing an ink jet recording material to be transferred onto the recording layer), and the pigment is obtained by grinding and dispersing an aggregate pigment in a cationic resin-containing liquid. And a pigment having an average aggregate particle size of 500 nm or less. [5] The ink jet recording material according to any one of [1] to [3], wherein the average particle size of the pulverized and dispersed aggregate is 300 nm or less.

[6] An ink jet recording medium containing a pigment in which the aggregate pigment is pulverized and dispersed in a liquid containing a cationic resin, and the average particle diameter of the aggregate is not more than the value before pulverization and not more than 500 nm. [7] In a method for producing an ink jet recording medium, in which a support is coated or impregnated with a pigment-containing coating liquid, the coating liquid is
A method for producing an ink jet recording material, which is a coating liquid containing a pigment in which an aggregate pigment is pulverized and dispersed in a cationic resin-containing liquid so that the average particle diameter of the aggregate is 500 nm or less.

[8] In a method for producing an ink jet recording medium, wherein a pigment-containing coating liquid is applied to or impregnated on a support, the coating liquid is obtained by pulverizing and dispersing an aggregate pigment in a cationic resin-containing liquid to reduce the average particle diameter of the aggregate. Less than the value before grinding and 5
A method for producing an ink jet recording medium, which is a coating liquid containing a pigment having a diameter of not more than 00 nm. [9] An ink jet recording medium containing a pigment obtained by pulverizing and dispersing an aggregate pigment in a liquid containing a cationic resin to have an average aggregate particle diameter of 500 nm or less.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In general, when mixing and dispersing a micron-order pigment with a cationic resin and a binder, even if the pigment in the dispersion slightly thickens, a coating obtained by coating is obtained. The average particle size is 5
When the colloidal particles having a size of not more than 00 nm are agglomerated with the pigment in the dispersion, not only the transparency of the coating layer is remarkably reduced, but also it is difficult to obtain a glossy surface having a rough surface and excellent smoothness. Particles such as silica are anionic in water, and of course, silica colloidal particles composed of aggregates (secondary particles and tertiary particles composed of primary particles) are also anionic. The anionic silica fine particles have no fixing property to the dye in the ink, and have poor moisture resistance and water resistance after printing. In order to increase the moisture resistance and water resistance after printing, it is essential to add a cationic resin or the like. But,
When a cationic resin is added to the anionic silica colloidal particles, aggregation occurs immediately, and it is difficult to obtain a glossy and transparent recording layer.

Accordingly, the present inventors have conducted intensive studies, and as a result, before agglomerating aggregates such as silica having a diameter of more than 500 nm, for example, silica of about 1 μm to about 50 μm, with mechanical force, to prepare a colloidal fine particle dispersion. , Adding a cationic resin,
After being dispersed together with aggregates such as silica, the mixture is pulverized by mechanical force. It was found that the prepared silica colloidal fine particle dispersion could obtain a uniform dispersion despite containing a cationic resin. When applied with a paint prepared by this method, an ink jet recording medium having high gloss, high print density, and good moisture resistance and water resistance after printing can be obtained. Although the reason is not clear, when the aggregates such as silica are pulverized and dispersed in the presence of the cationic resin, the adsorption of the cationic resin to the silica surface proceeds during the dispersion, and the adsorption becomes parallel at the time when the colloidal particles of 500 nm or less are formed. It is considered that the state has been reached, that is, the surface of the silica particles is almost completely covered with the cationic resin.

The dispersion obtained by dispersing the aggregate pigment by a mechanical method in the presence of a cationic resin and another water-soluble resin and pulverizing and dispersing the aggregate so that the average particle diameter of the aggregate is 500 nm or less is obtained. An ink jet recording medium having good properties, good coating suitability of the dispersion, and excellent gloss and print density can be obtained.

The present invention relates to an ink jet recording material containing a pigment obtained by pulverizing and dispersing an aggregate in the presence of a cationic resin so that the average particle size of the aggregate is 500 nm or less. Preferred dispersions of the pigment of the present invention are colloidal or slurry. The ink jet recording medium of the present invention has high gloss, excellent ink absorbency, high print density, and moisture and water resistance after printing.

In the present invention, the support is not particularly limited, and a transparent or opaque support can be used.
Cellophane, polyethylene, polypropylene, soft polyvinyl chloride, hard polyvinyl chloride, polyester and other plastic films, fine paper, art paper, coated paper, cast coated paper, foil paper, kraft paper, polyethylene laminated paper, impregnated paper, Paper such as vapor-deposited paper and water-soluble paper, metal foil, synthetic paper and the like are appropriately used.

The recording layer of the present invention comprises a single layer or multiple layers. First, when the recording layer is composed of a single layer, the recording layer contains at least a pigment as exemplified below.
Examples of the pigment include silica such as amorphous silica, clay, calcined clay, zinc oxide, tin oxide, magnesium sulfate, aluminum oxide, aluminum hydroxide, pseudoboehmite, calcium carbonate, satin white, aluminum silicate, smectite, and zeolite. , Magnesium silicate,
It is prepared by the following method using various pigments known and used in the general coated paper field, such as magnesium carbonate, magnesium oxide, and diatomaceous earth.

First, the pigment is dispersed in water or the like, and after adding a cationic resin, the pigment has an average particle diameter of 500 nm by a mechanical method.
Hereinafter, in order to further obtain a high printing density, the particles are pulverized and dispersed to secondary particles (dispersions) having an average particle diameter of preferably 10 to 300 nm. In order to obtain an aggregate having an average particle size of 500 nm or less, a commercially available aggregate of 1 to 50 μm is obtained by applying a strong force by mechanical means. That is, br
It can be obtained by an eak- ing down method (a method of pulverizing a bulk material). Ultrasonic,
Mechanical methods such as a high-speed rotation mill, a roller mill, a container driving medium mill, a medium stirring mill, a jet mill, a grinder, and a sand grinder are exemplified. All the average particle diameters referred to in the present invention are the particle diameters observed with an electron microscope (SEM and TEM) (Average Martin diameter; see "Fine Particle Handbook", Asakura Shoten, p. 52, 1991). The average particle size of the primary particles forming the aggregate is preferably from 3 nm to 40 nm. If the primary particle size is small, the absorption capacity may decrease,
Conversely, if it is large, the transparency of the ink recording layer may be reduced.

Amorphous silica, zeolite and calcium carbonate are preferred from the viewpoint of easiness of pulverization and dispersion stability. Of course, in addition to the dispersion obtained by the method described above, other commercially available pigments (eg, silica, colloidal silica, alumina, calcium carbonate, plastic pigment, etc.) may be used in a range that does not impair the transparency and gloss of the recording layer. May be used together. This can also improve the ink absorbency.

The cationic resin to be added is not particularly limited, but a water-soluble or aqueous emulsion type is preferably used. For example dicyan cationic resins represented by dicyandiamide-formalin polycondensate, polyamine-based cationic resins represented by dicyandiamide-diethylenetriamine polycondensate, epichlorohydrin-dimethylamine addition polymer, dimethyldiallylammonium chloride-SO ₂ copolymer, Diallylamine salt / SO ₂ copolymer, dimethyldiallylammonium chloride polymer, allylamine salt polymer, dialkylaminoethyl (meth) acrylate quaternary salt polymer,
A polycationic cation resin such as an acrylamide-diallylamine salt copolymer is exemplified. The amount of the cationic resin added is 1 to 3 with respect to 100 parts by weight of the pigment.
0 parts by weight, more preferably in the range of 3 to 20 parts by weight. Of course, a cationic resin may be further added after adding a small amount before the pulverization / dispersion and pulverization / dispersion until a desired particle size is obtained. The cationic resin is used alone or in combination. In addition, various auxiliaries such as dispersants, thickeners, antifoaming agents, coloring agents, antistatic agents, preservatives, etc. used in the production of general coated paper are appropriately dispersed before grinding, during grinding dispersion, or after grinding dispersion. Is added.

It is essential to add an adhesive (binder) to the recording layer of the present invention. As an adhesive (binder),
Water-soluble resin (for example, polyvinyl alcohol (hereinafter referred to as PV)
A), casein, soy protein, synthetic proteins,
Starch, cellulose derivatives such as carboxymethylcellulose and methylcellulose), styrene-butadiene copolymer, conjugated diene-based polymer latex of methyl methacrylate-butadiene copolymer, acrylic polymer latex, vinyl such as styrene-vinyl acetate copolymer A known adhesive (binder) generally used for coated paper, such as a system copolymer latex, is used alone or in combination. The adhesive is preferably a water-soluble resin. Although the reason is not clear, it seems that the water-soluble resin, unlike latex, can cover a part of the pigment surface such as silica in the aqueous solution, or the cationic resin may be more easily added. . The adhesive may be partially or entirely added at any stage before, during, or after the pulverization and dispersion of the pigment. Preferably, a part of the adhesive is added to the pigment together with the cationic resin before the pulverization of the pigment. The amount of adhesive added before pulverization is 5-5 of the total amount
0%, preferably 10 to 40%. If the entire amount of the adhesive is added before the pulverization, the adhesive may be sucked between the primary particles during the pulverization, and the ink absorption capacity may be reduced.

The weight ratio of the solid content of the pigment and the adhesive (binder) in the recording layer is not particularly limited, but is adjusted in the range of 5 to 200 parts by weight, preferably 10 to 100 parts by weight, per 100 parts by weight of the pigment. If the amount of the adhesive (binder) is large, the pores between the particles become small, and it is difficult to obtain an ink absorption rate. On the other hand, if the amount of the adhesive (binder) is small, the coating layer tends to crack. The coating amount of the recording layer is not particularly limited, 1~100g / m ^2, preferably adjusted to 5 to 70 g / m ^2. If the amount is small, it is difficult to obtain a uniform coating film, and if the amount is large, the effect is saturated, and the coating film is easily cracked.

In the structure having two or more recording layers on the support, at least one layer is obtained by the method described above.
This is a layer containing a colloidal pigment of nm or less. The basic configuration of the other recording layers is composed of the same composition as the single-layer recording layer. That is, a layer containing a pigment and an adhesive as exemplified above or a layer containing a polymer exemplified as an adhesive can be used. When the recording layer of the present invention is coated on a smooth molding surface and then transferred onto a support or another recording layer, more excellent gloss can be obtained. As the material used for the molding surface,
For example, cellophane with high surface smoothness, polyethylene,
Flexible films such as plastic films such as polypropylene, soft polyvinyl chloride, hard polyvinyl chloride, and polyester; papers such as polyethylene laminated paper, glassine paper, impregnated paper, and vapor-deposited paper; metal foils; synthetic paper; Drums and plates having a highly smooth surface such as inorganic glass, metal, and plastic are appropriately used. In particular, a polymer film (polyethylene, polypropylene, polyester, or the like) or a metal drum having a highly smooth surface is preferable from the viewpoints of the manufacturing process and the suitability for separation between the molding surface and the recording layer.

The molded surface is preferably smooth for the purpose of imparting gloss, and the surface roughness of the molded surface (JIS B-06)
01), Ra is preferably 0.5 μm or less, more preferably Ra is 0.05 μm or less. In addition, it is also possible to give a texture such as semi-gloss tone or matte tone by controlling the surface roughness. The molding surface may be left untreated. However, in order to control the adhesive force between the molding surface and the recording layer to be smaller than the adhesive force between the recording layer and the support (or another recording layer), the coating surface of the molding surface is coated with silicone. It is possible to coat and use a compound having releasability, such as fluorine or a fluororesin.

Examples of the coating coater for the recording layer of the present invention include various known coating apparatuses such as a blade coater, an air knife coater, a roll coater, a bar coater, a gravure coater, a rod blade coater, a lip coater, a curtain coater, a die coater and the like. An impregnating device such as a size press may be used. As the ink used in the inkjet recording method of the present invention, a dye for forming an image and a liquid medium for dissolving or dispersing the dye are essential components, and various dispersants, surfactants, if necessary, It is adjusted by adding a viscosity adjusting agent, a specific resistance adjusting agent, a pH adjusting agent, a fungicide, a dissolution or dispersion stabilizer of the recording agent, and the like.

Examples of the recording agent used in the ink include direct dyes, acid dyes, basic dyes, reactive dyes, edible dyes, disperse dyes, oil dyes, and various pigments. Can be used without. The content of such a dye is determined depending on the type of the liquid medium component, the characteristics required for the ink, and the like, but in the case of the ink of the present invention, the composition as in the conventional ink, that is, There is no particular problem in use at a ratio of about 0.1 to 20% by weight. Examples of the solvent for the ink used in the present invention include water and various water-soluble organic solvents, for example, having 1 to 4 carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, and isobutyl alcohol. Alkyl alcohols, ketones or ketone alcohols such as acetone and diacetone alcohol, polyalkylene glycols such as polyethylene glycol and polypropylene glycol, ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, thiodiglycol, Alkylene glycols having 2 to 6 alkylene groups such as xylene glycol and diethylene glycol, amides such as dimethylformamide, ethers such as tetrahydrofuran, and glycerin Ethylene glycol methyl ether, diethylene glycol methyl (ethyl) ether, lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl ether and the like.

[0023]

The present invention will be described in more detail with reference to the following Examples, but it should be understood that the present invention is by no means restricted thereto.
Unless otherwise specified, parts and% in the examples are solid contents excluding water, and represent parts by weight and% by weight, respectively. still,
The dispersion particle size measurement method is as follows. Observation was performed with a TEM (transmission electron microscope, H-300, manufactured by Hitachi, Ltd.). After diluting the dispersion to 0.5%, it is dropped on the collodion film,
After air drying, it was used for observation. Electron microscope magnification is 20,000 times,
It was appropriately selected from 50,000 times and 100,000 times.

Example 1 Synthetic amorphous silica having an average particle size of 3 μm (Nippon Silica Industry Co., Ltd.)
Product name: Nipsil HD-2, primary particle size: 1
1 nm, hereinafter also referred to as HD-2) 50 parts with water 950
Part, sodium polyacrylate (Toagosei Chemical Industry Co., Ltd.)
(Trade name: A-9, hereinafter also referred to as A-9)
And while dispersing with a homomixer,
To diallyldimethylammonium chloride-acryl
Luamide copolymer (trade name: PAS-J, manufactured by Nitto Boseki Co., Ltd.)
-81, hereinafter simply referred to as PAS-J-81).
Added. Then, pulverize and disperse with a sand grinder
After that, further pulverized and dispersed with a pressure homogenizer, average
Sand grinder and pressure until particle size reaches 120nm
The grinding and dispersing operation of the force homogenizer was repeated. Get
10% polyvinyl alcohol in a water dispersion
Aqueous solution of rucol (manufactured by Kuraray, trade name: PVA117
25 parts (in terms of solid content, hereinafter also referred to as PVA117)
Add the same) and stir until uniform, then dry coat
20g / m^TwoCommercially available coated paper (Oji Paper Co., Ltd.)
Product name: OK coat, 127.9 g / m ^TwoLami)
(By extrusion lamination)
15μm polyethylene laminated on the surface of coated paper
(Hereinafter simply referred to as laminated coated paper)
After drying, the ink jet recording medium of the present invention was manufactured.

Example 2 Synthetic amorphous silica having an average particle diameter of 3 μm (trade name: Nipsil HD-2, manufactured by Nippon Silica Industry Co., Ltd., primary particle diameter: 1)
1 nm) 50 parts of water, 800 parts of water and 2 parts of sodium polyacrylate (trade name: A-9, manufactured by Toagosei Chemical Industry Co., Ltd.) are added, and dispersed with a homomixer, and 10% of polyvinyl alcohol prepared in advance is dispersed. (Kuraray Co., Ltd., trade name: PVA117) 5 parts of an aqueous solution (in terms of solid content), the cationic resin diallyldimethylammonium chloride-acrylamide copolymer (trade name: P, manufactured by Nitto Boseki Co., Ltd.)
AS-J-81). Subsequently, after pulverized and dispersed by a sand grinder, the mixture was further pulverized and dispersed by a pressure homogenizer, and the pulverization and dispersion operation of the sand grinder and the pressure homogenizer was repeated until the average particle diameter became 120 nm. The above 10% polyvinyl alcohol (PVA-11) previously prepared in the obtained aqueous dispersion.
7) After adding 20 parts (in terms of solid content) of an aqueous solution and stirring until the mixture becomes uniform, the mixture was coated on the same laminated coated paper as above so as to have a coating amount of 20 g / m ² and dried. Was manufactured.

Example 3 Using the same coating liquid as in Example 2, the coating amount was 20 g / m ^2.
PET film (Lumilar T, manufactured by Toray Industries, Inc.)
(75 μm, surface roughness R _a = 0.02 μm). Subsequently, the recording layer was pressure-bonded under the conditions of a calendar at a temperature of 80 ° C. and a linear pressure of 30 Kg / cm so that the laminated surface of the same laminated coated paper as described above faces PET.
The film was peeled off to produce the ink jet recording medium of the present invention. Comparative Example 1 Synthetic amorphous silica having an average particle diameter of 3 μm (manufactured by Nippon Silica Industry Co., Ltd., trade name: Nipsil HD-2, primary particle diameter: 1)
950 parts of water and 2 parts of sodium polyacrylate (trade name: A-9, manufactured by Toagosei Chemical Industry Co., Ltd.) are added to 50 parts of 1 nm), and the above-mentioned cationic resin (Nitto Boseki) is dispersed with a homomixer. (Product name: PAS-J-81)
5 parts, and 25 parts (in terms of solid content) of 10% polyvinyl alcohol (the above-mentioned trade name: PVA117) prepared in advance were added. Stirring was continued until the pigment became uniform, and the average particle diameter of the obtained aqueous dispersion was 3 μm. Using this paint, it was coated on the same laminated coated paper as above so as to have a coating amount of 20 g / m ² and dried to produce an ink jet recording medium. Comparative Example 2 Synthetic amorphous silica having an average particle diameter of 3 μm (manufactured by Nippon Silica Industry Co., Ltd., trade name: Nipsil HD-2, primary particle diameter: 1)
(1 nm) To 50 parts of water, 950 parts of water was added, and the mixture was pulverized and dispersed by a sand grinder, further pulverized and dispersed by a pressure homogenizer, and the dispersion operation of the sand grinder and the pressure homogenizer was repeated until the average particle diameter became 120 nm. . 10 prepared in advance in the obtained aqueous dispersion.
% Polyvinyl alcohol (the above-mentioned trade name: PVA11)
7) 25 parts (in terms of solid content) and 5 parts of the aforementioned cationic resin (trade name: PAS-J-81, manufactured by Nitto Boseki Co., Ltd.) were added,
The mixture was stirred until the coating liquid became uniform (the coating liquid was thickened by the addition of the cationic resin), and was coated and dried on the same laminated coated paper as described above so that the coating amount was 20 g / m ² . An ink jet recording medium was manufactured.

Comparative Example 3 Synthetic amorphous silica having an average particle diameter of 3 μm (manufactured by Nippon Silica Industry Co., Ltd., trade name: Nipsil HD-2, primary particle diameter: 1)
1 nm) 950 parts of water was added to 50 parts, pulverized and dispersed by a sand grinder, further pulverized and dispersed by a pressure homogenizer, and the pulverization and dispersion operation of the sand grinder and the pressure homogenizer was repeated until the average particle diameter became 120 nm. . 10 prepared in advance in the obtained aqueous dispersion
% Polyvinyl alcohol (the above-mentioned trade name: PVA11)
7) 25 parts (in terms of solid content) were added, and the coating amount was 20 g /
It was coated and dried on the same laminated coated paper as described above so as to obtain m ² , thereby producing an ink jet recording medium.

[Evaluation Methods] The ink absorbency, glossiness, print water resistance and the like of the ink jet recording materials obtained in Examples and Comparative Examples were evaluated by the following methods. The gloss and the ink absorbency indicate the gloss, ink absorbency, and print density of a solid portion when recording is performed with a commercially available inkjet printer (trade name: BJC-600J, manufactured by Canon Inc.). [Water resistance to printing] After printing on an inkjet recording medium,
After standing for 24 hours, water drops are dropped, and after 30 minutes, the water drops are wiped off, and the state of immersion in the water drops is observed. (A: There was almost no ink bleeding. B: There was ink bleeding, and the density of the printed portion was low. C: Most of the ink was removed.)

[Ink Absorbency] Print each single color of yellow, magenta, and cyan, attach fine wood to the printed surface every 5 seconds immediately after printing, and observe whether the ink is transferred to the fine wood. . (○: less than 10 seconds, Δ: 10
30 seconds, x: 30 seconds or more). When the time until the ink dries is less than 10 seconds, the ink absorbency is excellent.

[Print Density] The print density of the solid black portion was measured using a Macbeth reflection densitometer (Macbeth, RD-920). The numbers shown in the table are the average values of five measurements. [Glossiness of print portion (shininess)] The glossiness of the print portion was visually observed from a lateral angle of 20 ° with respect to the print portion, and evaluated in four steps as follows. ：: There is the same level of shine as a silver halide color photograph. ：: Inferior to color photograph, but with high shine. Δ: comparable to coated paper print product. X: comparable to general PPC.

[0031]

[Table 1]

[0032]

As is evident from Table 1, the ink jet recording medium obtained by the constitution of the present invention is an ink jet recording medium having good ink absorbability and excellent gloss, print density and water resistance even after printing. is there.

Claims (4)

[Claims] 1. An ink jet recording material comprising a support and a pigment-containing coating liquid applied or impregnated thereon, wherein the coating liquid is obtained by pulverizing and dispersing an aggregate pigment in a cationic resin-containing liquid to have an average particle diameter of 500 nm. An ink jet recording material, which is a coating liquid containing a pigment described below. 2. The ink jet recording medium according to claim 1, wherein the cationic resin-containing liquid further contains a water-soluble resin. 3. The method of claim 1, wherein the aggregate pigment comprises amorphous silica.
Or the ink-jet recording material according to 2. 4. A method for producing an ink jet recording medium having a recording layer provided on a support, wherein at least one recording layer contains a pigment, and after being coated and formed on a molding surface, is formed on the support (or If another recording layer is already provided on the support, the method is a method for producing an ink jet recording material to be transferred onto the recording layer), and the pigment is obtained by grinding an aggregate pigment in a liquid containing a cationic resin. Disperse, and agglomerate average particle size is 50
A method for producing an ink jet recording material, which is a pigment having a diameter of 0 nm or less.