JPH08324098A - Ink jet recording medium and production thereof - Google Patents

Abstract

PURPOSE: To produce an ink jet recording medium having high surface uniformity and imparting recording high in gloss, transparency, optical density and image quality. CONSTITUTION: High speed streams of a plurality of raw material solns. containing alumina hydrate are allowed to collide with each other to prepare a dispersion of alumina hydrate and the prepared dispersion is applied to the surface of a sheet like support and dried to form an ink receiving layer on the surface of the support.

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 used in an ink jet recording apparatus and the like, and a method for producing the same. .

[0002]

2. Description of the Related Art An ink jet recording system is one in which minute droplets of ink are ejected according to various operating principles and adhered to a recording medium such as paper to record images, characters, etc. It is characterized by easy multicoloring, great flexibility in recording patterns, and no need for development and fixing. Therefore, as a recording system of various image recording apparatuses, it is rapidly spreading in various applications such as information equipment. Furthermore, images formed by the multicolor ink jet system can be recorded in comparison with multicolor printing by the plate making system and printing by the color photographic system. Since it can be manufactured at a lower cost than multicolor printing and printing, it is being widely applied to the field of full-color image recording. Faster recording,
Although the recording apparatus and the recording method have been improved in response to the demand for higher recording characteristics such as higher definition and full color, higher characteristics have also been required for recording media.

In order to solve such a problem, various forms of recording media have been conventionally proposed. For example, Japanese Unexamined Patent Publication No. 52-53012 discloses an inkjet paper in which a low-sized base paper is impregnated with a surface-treatment coating material. JP-A-53-49113 discloses an inkjet paper in which a sheet containing urea-formalin resin powder is impregnated with a water-soluble polymer. JP-A-55-5830 discloses an ink jet recording paper having a support surface provided with an ink-absorptive coating layer, and JP-A-55-51583 discloses amorphous as a pigment in a coating layer. An example using silica is disclosed and disclosed in JP-A-55-14.
Japanese Patent No. 36786 discloses an example using a water-soluble polymer coating layer.

Further, in recent years, recording media having a coating layer using alumina hydrate having a boehmite structure have been proposed, for example, US Pat. Nos. 4,879,166 and 5;
104730, JP-A-2-276670, and JP-A-4
These recording media are disclosed in Japanese Patent Laid-Open Nos. 37576 and 5-32037.

In the recording medium using these alumina hydrates in the coating layer, since the alumina hydrates have a positive charge, the fixability of the ink dye is good and an image with good color development can be obtained. , There is no problem such as browning of black ink, light resistance, etc., which has occurred by using a silica compound,
Further, there are advantages such as preferable image quality, particularly in terms of image quality and gloss in a full-color image, as compared with conventional recording media.

In the production of an ink jet recording medium using the above-mentioned alumina hydrate in a coating layer, a ball mill, an attritor, a sand mill or a homogenizer is used to prepare a coating solution by dispersing the alumina hydrate in a solvent. Dispersers such as mixers have been used conventionally. However, all of the dispersers have poor dispersion efficiency, which makes it difficult to form fine particles, has a wide particle size distribution, and has a problem that it is difficult to obtain a uniformly dispersed coating liquid. For this reason, in response to the recent demand for higher image quality of inkjet recording media, the reduction in the filling ratio of the dispersion such as alumina hydrate lowers the high glossiness, lowers the transparency, and lowers the recording density accordingly. There is a problem.

Further, the dispersion containing alumina hydrate is
After the preparation, the viscosity increases with time and the coating becomes difficult, so that there is a problem that the solid content concentration of the liquid cannot be increased. Japanese Unexamined Patent Publication No. 4-67986 discloses a method of lowering the degree of polymerization of the binder polymer, but this method has problems such as poor appearance such as cracks in the ink receiving layer and reduced water resistance.

Further, Japanese Patent Laid-Open No. 4-67985 discloses that
Although a method of adding an acid such as a monocarboxylic acid as a dispersant is disclosed, there are problems in production such as generation of irritating odor and corrosion.

[0009]

DISCLOSURE OF THE INVENTION As a result of various investigations by the present inventors in order to solve the above problems, (1) the dispersion efficiency of a pigment such as alumina hydrate used in an ink jet recording medium is high and the time is short. A method for providing a dispersion in which fine particles are uniformly and stably dispersed.

(2) A method for lowering the viscosity of a dispersion containing an alumina hydrate and stabilizing the viscosity with time. The present invention has been completed and completed the present invention. The purpose of the invention is to provide high surface uniformity, high gloss, high transparency, high optical density recording, and high image quality. An object of the present invention is to provide a method for manufacturing an inkjet recording medium.

[0011]

In order to achieve the above object, the present invention comprises a step of preparing a dispersion liquid of alumina hydrate by colliding high-speed streams of a plurality of raw material liquids containing alumina hydrate with each other. And a step of forming an ink receiving layer on the surface of the support by applying the prepared dispersion onto the surface of the sheet-like support and then drying the dispersion, the method for producing an inkjet recording medium is proposed. Is what
The collision pressure of the high-speed flow is 5 to 1500 kg / cm ² , and the content of alumina hydrate in the dispersion liquid is 100 g of the solvent.
0.5 to 40 g, the total pore volume of the ink receiving layer is 0.1 to 1.0 ml / g, and the BET specific surface area is 20 to 450 m ² / g.

Further, the present invention is an ink jet recording medium manufactured by the above manufacturing method.

[0013]

In the present invention, the raw material liquid containing the alumina hydrate is collided with a high-speed flow as described above, whereby the alumina hydrate can be finely and uniformly crushed to obtain a good dispersion liquid. Is. The viscosity of the dispersion liquid thus prepared has little change with time.

The present invention will be described in detail below with reference to the drawings.

First, the dispersion mechanism used in the present invention will be described. FIG. 1 shows the outline of the dispersion method.

Raw material liquid 2 containing at least alumina hydrate
a and 2b are high pressure (5 to 1500) in the supply passages 1a and 1b.
These raw material liquids 2 are fed under a pressure of ² kg / cm ² ).
The a and 2b collide with each other at a high speed, and the solid particles (alumina hydrate) in the flow are crushed and atomized by this collision force. In this case, the raw material liquids 2a and 2b may be the same or different, and the flow rate, the pressure and the like can be arbitrarily combined.

Further, as shown in FIG. 1, the raw material liquid 2 is not made to collide from only two directions but from three directions as shown in FIG.
The a, 2b, 2c may collide with each other through the supply passages 1a, 1b, 1c, or, although not shown, they may collide with each other in four or more directions.

The raw material liquid used in the present invention comprises at least an alumina hydrate described below and a solvent.

Preferred solvents include water, alcohols, esters, aromatic hydrocarbons and the like, and these may be used in combination.

The ratio of the solvent used as the raw material liquid and the alumina hydrate is not particularly limited, but 0.5 g to 40 g, more preferably 2 g to 3 g of the alumina hydrate with respect to 100 g of the solvent.
0 g is preferred.

In the method according to the present invention, prior to the dispersion operation of the present invention, a conventional dispersion operation is carried out by preliminarily dispersing the raw material liquid,
For example, a dispersing operation using a ball mill, an attritor, a sand mill, a homomixer or the like may be performed. Further, the dispersion operation of the present invention may be carried out not only once but a plurality of times.

During the dispersion treatment, the temperature of the dispersion liquid is preferably cooled or kept warm to keep it within a certain range. The preferred temperature range varies depending on the dispersion treatment method, the material and the viscosity, but is in the range of 10 to 100 ° C. If it is lower than the above range, the dispersion treatment may be insufficient or agglomeration may occur. If it is higher than the above range, gelation may occur or the crystal structure may change.

As shown in FIG. 3, the ink jet recording medium of the present invention has a constitution in which an ink receiving layer 4 mainly composed of alumina hydrate and a binder is formed on a support 3.

The support may be appropriately sized paper, non-sized paper, resin-coated paper or the like, sheet-like material such as thermoplastic film, and cloth, and there is no particular limitation.

Polyester in the case of a thermoplastic film,
It is also possible to use a transparent film of polystyrene, polyvinyl chloride, polymethylmethacrylate, cellulose acetate, polyethylene, polycarbonate or the like, or an opaque sheet filled with alumina hydrate or titanium white or finely foamed.

When resin-coated paper is used as the support, the same feel, feel and texture as those of ordinary photographic prints can be obtained, and the recording medium of the present invention has a high gloss in the ink receiving layer. In some cases, it is a close approximation of a regular photographic print.

Further, in order to improve the adhesion between the support and the ink receiving layer, a surface treatment such as corona treatment or flame treatment may be carried out, or an easily adhesive layer may be provided as an undercoat layer. Further, in order to prevent curling, a curl preventing layer such as a resin layer or a pigment layer may be provided on the back surface of the support or at a predetermined portion.

The ink receiving layer formed on the ink jet recording medium of the present invention has a total pore volume of 0.1 to 1.
It is preferably formed in the range of 0 ml / g. When the pore volume of the ink receiving layer is larger than the above range, cracking and powder drop occur in the ink receiving layer, and when it is smaller than the above range, ink absorption becomes poor, especially when multicolor printing is performed. Ink easily overflows from the ink receiving layer, causing bleeding in the image.

The BET specific surface area of the ink receiving layer is preferably ^{20 to} 450 m ² / g. When it is less than this range, the glossiness of the ink receiving layer is lost, and haze is increased, so that white smear appears on the image. On the other hand, when it is larger than the above range, cracks are likely to occur in the ink receiving layer.

The BET specific surface area and pore volume are 24
After deaeration at 120 ° C. for a time, it can be determined by the nitrogen adsorption / desorption method.

The ink receiving layer is formed by applying a dispersion containing an alumina hydrate and a binder on a support and drying it.

The binder is preferably a water-soluble polymer substance. For example, polyvinyl alcohol or a modified product thereof (cation modified, anion modified, silanol modified), starch or a modified product thereof (oxidized or etherified), gelatin or a modified product thereof, casein or a modified product thereof,
Cellulose derivatives such as carboxymethyl cellulose, gum arabic, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, SBR latex, NBR
Latex, conjugated diene-based copolymer latex such as methyl methacrylate-butadiene copolymer, functional group-modified polymer latex, vinyl-based copolymer latex such as ethylene-vinyl acetate copolymer, polyvinylpyrrolidone, maleic anhydride or a copolymer thereof. Polymers, acrylic acid ester copolymers, acrylamide resins and the like are preferable.

When an organic solvent is used, polyamide-based resin, polyurethane-based resin, polyester-based resin, polyvinyl acetal-based resin, acrylic resin and the like can be mentioned. These binders can be used alone or in combination of two or more.

As long as the BET specific surface area and the pore volume of the ink receiving layer are satisfied, the mixing ratio of the alumina hydrate and the binder is 1: 1 to 30: 1 by weight, preferably 5: 1 to. It can be arbitrarily selected between 20: 1. When the amount of the binder is less than the above range, the mechanical strength of the ink receiving layer is insufficient, and cracking and powder falling occur, and when the amount is more than the above range, the pore volume is reduced and the ink absorption is reduced. Deteriorate.

It is preferable to use a coating device for coating.

As a coating method, a blade coating method,
An air knife method, a roll coating method, a brush coating method, a gravure coating method, a kiss coating method, an extrusion method, a slide hopper (slide bead) method, a curtain coating method, a spray method and the like can be used.

As a drying device for the applied coating liquid, a hot air dryer such as a straight tunnel dryer, an arch dryer, an air loop dryer, and a sine curve air float dryer, a dryer using infrared rays, a heating dryer, a microwave, etc. Etc. Various drying devices can be mentioned.

The coating amount of the dispersion liquid is 0.5 in terms of dry solid content.
-60 g / m < ² >, more preferably 5-45 g / m < ² >, but in order to obtain good ink absorption and resolution,
It is necessary to set the thickness of the ink receiving layer to m or more, preferably 20 μm or more, and particularly 25 μm or more.

Next, the components of the dispersion liquid will be described.

The alumina hydrate used in the present invention is represented by the following general formula.

[0041] During _{Al 2 O 3-n (OH} ) 2n · mH 2 O formula, n represents either of the integers 0, 1, 2 or 3, m is 0-10, preferably 0-5 Represents a value. mH
_In most cases, ₂ O represents a detachable aqueous phase that does not participate in the formation of the crystal lattice, so m can take a non-integer value. Also, when this type of alumina hydrate is calcined, m can reach a value of zero.

Alumina hydrate suitable for carrying out the present invention is an amorphous alumina hydrate as analyzed by X-ray diffraction method, and particularly, Japanese Patent Application Nos. 5-125437 and 5-12.
No. 5438, No. 5-125439, No. 6-11457.
The alumina hydrate described in No. 1 is preferably used. In particular, the alumina hydrate is preferably an amorphous compound. Further, the alumina hydrate is preferably a tabular alumina hydrate having an average aspect ratio of 3 to 10.

Although the physical properties of the pores of the alumina hydrate are adjusted in the production process, the BE of the ink receiving layer is adjusted.
In order to obtain an inkjet recording medium having a T specific surface area and a pore volume, it is preferable to use an alumina hydrate having a pore volume of 0.1 to 1.0 ml / g. If the pore volume of the alumina hydrate is out of the above range, it becomes difficult to bring the pore volume of the ink receiving layer into the specified range.

The BET specific surface area is 40 to
It is preferable to use an alumina hydrate that is 500 m ² / g. If the specific surface area of the alumina hydrate is outside the above range,
It becomes difficult to make the specific surface area of the ink receiving layer within the specified range.

Further, the following pigments other than alumina hydrate may be mixed and used.

Examples of the pigment used in the ink jet recording medium of the present invention include calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titania, zinc oxide, zinc carbonate, aluminum silicate, alumina, silicic acid and silicic acid. Sodium, magnesium silicate,
It is possible to use inorganic pigments such as calcium silicate and silica, organic pigments such as plastic pigments and urea resin pigments, and combinations thereof.

As long as the BET specific surface area and pore volume of the ink receiving layer are satisfied, the mixing ratio of the pigment and the binder is 1: 1 to 30: 1 by weight, preferably 5: 1 to 20: 1. Can be arbitrarily selected between. When the amount of the binder is less than the above range, the mechanical strength of the ink receiving layer is insufficient, and cracking and powder drop occur, and when the amount is more than the above range, the pore volume is small and the ink absorption is poor. Become.

If necessary, the dispersion containing the alumina hydrate and the binder contains a dispersant, a thickener, a pH adjustor, a lubricant, a fluidity modifier, a surfactant, a defoaming agent, and a water resistant agent. ,
It is also possible to add a foam suppressor, a release agent, a foaming agent, a penetrant, a coloring dye, a fluorescent whitening agent, an ultraviolet absorber, an antioxidant, a preservative, and an antifungal agent, if necessary.

The waterproofing agent can be freely selected from known materials such as halogenated quaternary ammonium salts and quaternary ammonium salt polymers.

The ratio (viscosity over time / initial viscosity) of the viscosity of the dispersion of the present invention at the initial stage immediately after dispersion to the viscosity after storage for 10 days is preferably 0.5 to 3. . Outside this range, the pot life of the dispersion becomes short, which causes problems in coating stability and storage stability of the dispersion. A more preferable range is 0.5 to 2.5. Within this range, defoaming of the dispersion liquid is easy, so that productivity is improved and at the same time coating defects can be prevented. According to the present invention, the dispersion is excellent in stability over time and storage stability, and can maintain a stable dispersed state for a long period of time.

The ink receiving layer in the present invention may have a single layer structure or a multilayer structure. Examples of the multilayer structure include those described in JP-A Nos. 57-89954, 60-224578 and 61-12388. For example, the ink passage layer described in JP-A No. 61-12388 may be further provided on the ink receiving layer of the present invention. Further, the ink receiving layer is provided on at least one side of the support, but it may be provided on both sides of the support for the purpose of curling prevention, inkjet recording on both sides, and the like.

[0052]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. Preparation of Alumina Hydrate Aluminum dodoxide was prepared by the method described in US Pat. No. 4,242,271. Next, the aluminum alkoxide was hydrolyzed by the method described in U.S. Pat. No. 4,202,870 to produce an alumina slurry. Water was added to this alumina slurry until the solid content of alumina hydrate reached 7.9%. The pH of the alumina slurry was 9.5. The pH was adjusted by adding a 3.9% nitric acid solution to obtain a colloidal sol. This colloidal sol was spray dried at 75 ° C. to obtain alumina hydrates (AB) shown in Table 1. BET of these alumina hydrates
The specific surface area and pore volume were determined by the methods described below. Table 1 shows the results. (Evaluation items) 1) Pore volume (PV) and BET specific surface area (SA) The pore volume was measured using a nitrogen adsorption / desorption method after degassing at 120 ° C. for 24 hours (manufactured by Kantachrome Co., Ltd.). , Autosoap I).

The BET specific surface area was calculated and calculated using the method of Brunauer et al.

[0054]

[Table 1] Example 1 A dispersion liquid (solid content concentration: 25% by weight) in which the above-mentioned alumina hydrate A was dispersed in ion-exchanged water and polyvinyl alcohol (Nippon Gosei Chemical Co., Ltd., Gohsenol NH-18).
Aqueous solution (solid content concentration 10% by weight) and acidic method gelatin (weight average molecular weight 100,000, number average molecular weight: 410,000, pH:
7.0, iso-ion point: 7.1) Aqueous solution (solid content 10
(% By weight) so that the solid content weight ratio is alumina hydrate / polyvinyl alcohol / gelatin of acidic method = 150/8/2, and the solid content concentration is 22% by weight, mixed, and pre-stirred to obtain a mixed dispersion liquid. Got (P / B ratio = alumina solid content weight / binder solid content weight = 15/1, binder ratio =
Polyvinyl alcohol solid content weight / gelatin solid content weight = 8/2).

Next, the pre-stirred stock solution was charged into a disperser (trade name: Harmonizer: manufactured by Nanomizer Co., Ltd.), and the stock solution was subjected to a dispersing operation by a high-speed collision method. The pressure at the time of collision at this time was 15 kgf / cm ² .

This dispersion was applied onto resin-coated paper (manufactured by Shin Oji Paper Co., Ltd., thickness 180 μm: RC) using a gravure coater to form an ink-jet receiving layer having a dry coating thickness of 35 μm. An inkjet recording medium was obtained.

The physical properties of the coating liquid and the ink receiving layer which had been dispersed were measured by the methods described below. Table 2 shows the results. Evaluation / Measurement Method of Dispersion Liquid 1) Initial viscosity (η ₀ ) and viscosity after 10 days (η ₁₀ ) Measured using a B-type rotational viscometer (VISCOMETER manufactured by TOKIMEC). (30 rpm / 20 ° C.).

The initial viscosity (η ₀ ) of the dispersion liquid is
Measured immediately. 400 ml of the dispersion was sampled, sealed tightly and allowed to stand for 10 days. Then, the viscosity was measured in the same manner, and the viscosity after 10 days (η ₁₀ ) was obtained. Viscosity change rate (%) = viscosity after 10 days (η ₁₀ ) / initial viscosity (η ₀ ) × 100 Evaluation and measurement method of ink receiving layer 1) Glossiness Gloss meter (Gloss Checker IG-3 manufactured by Horiba Ltd.)
20) was used to measure the non-printed portion at 7 points, and the average value was obtained.

2) Printed image density An ink jet head having 128 nozzles at a nozzle interval of 16 at a ratio of 1 mm was used as a Y. M. C. Bk 4
Inkjet recording was performed with an ink having the following ink composition 1 using an inkjet printer provided with color components.
Y. M. C. The image densities of the images solidly printed with the Bk ink were measured using a Macbeth reflection densitometer RD-1255.

Ink Composition 1 Dye 5 parts by weight Glycerin 10 parts by weight Polyethylene glycol 10 parts by weight Water 75 parts by weight Ink dye Y: C.I. I. Direct Yellow 86 M: C.I. I. Acid Red 35 C: C.I. I. Direct Blue 199 Bk: C.I. I. Food Black 2 Examples 2 to 6 Preliminary stirring was carried out in the same manner as in Example 1 according to the formulation shown in Table 2, and then the stock solution was dispersed (trade name: Nanomizer; Nanomizer).
Co., Ltd., and the dispersion operation was performed by the method of the present invention in which the stock solutions collide with each other at high speed.

Table 2 shows the pressure at the time of collision.

A transparent polyethylene terephthalate film (manufactured by Toray Industries, Inc., Lumirror T, thickness 10
0 μ: TP), white polyethylene terephthalate film (manufactured by Toray Industries, Inc., Lumirror X-21, thickness 100 μ)
m: WP) or the resin-coated paper (RC) described above was coated in the same manner as in Example 1 to obtain an inkjet recording medium of the present invention. Evaluation was carried out in the same manner as in Example 1. Table 2 shows the results.

The transparency of the recording medium using a transparent polyethylene terephthalate film as the support was also evaluated.

3) Transparency Without printing on the ink jet recording medium, the transmittance was measured using a haze meter (NDH-100IDP, Nippon Denshoku Industries Co., Ltd.). Table 2 shows the results. Example 7 Preliminary stirring was carried out in the same manner as in Example 1 with the formulation shown in Table 2,
Then, the stock solution was charged into a disperser (trade name: Microfluidizer, using Y type chamber; manufactured by Microfluidics Co., Ltd.), and the stock solution was dispersed by a method of the present invention in which the stock solutions collide at high speed. Table 2 shows the collision pressure at this time.

Thereafter, coating and evaluation were carried out in the same manner as in Example 1. Table 2 shows the results. Example 8 Preliminary stirring was carried out in the same manner as in Example 1 with the formulation shown in Table 2,
Next, disperse the stock solution (trade name: ULTIMIZER;
(Tau Technology Co., Ltd.) and the dispersion was carried out by the method of the present invention in which the undiluted solutions collide at high speed. Table 2 shows the collision pressure at this time.

Thereafter, coating and evaluation were carried out in the same manner as in Example 1. Table 2 shows the results. Comparative Example 1 Instead of the disperser used in Example 1, a T.S. K. 8000rp using Homomixer M type (made by Tokushu Kika Kogyo Co., Ltd.)
It was stirred at m for 30 minutes. Otherwise, a recording medium was prepared and evaluated in the same manner as in Example 1. Table 2 shows the results.
Compared with Example 1, the initial viscosity of the coating liquid was high and the viscosity increase with time was large. Further, the glossiness of the medium and the printed image density were poor. Comparative Example 2 Example 2 was repeated except that a sand mill (manufactured by IMEX Co., Ltd.) was used instead of the disperser used in Example 2 for dispersion.
A recording medium was prepared and evaluated in the same manner as in. Table 2 shows the results
Shown in Compared with Example 2, the initial viscosity of the coating liquid is high,
The thickening with time was also large. Further, the glossiness of the medium, the print image density, and the transparency were poor.

[0067]

[Table 2]

[0068]

As described above, according to the present invention, (1) the dispersion efficiency of the alumina hydrate and pigment used in the ink jet recording medium is high, so that the productivity is good and the ink is stable uniformly in a short time. A dispersion liquid in which the fine particles are dispersed is obtained.

(2) The viscosity of the dispersion containing the alumina hydrate can be lowered and the viscosity can be stabilized with time, and a receiving layer having a good thickness can be stably formed with good productivity.

(3) It is possible to obtain an ink jet recording medium having high surface uniformity, high gloss and transparency, high recording optical density and high image quality. Especially when resin coated paper is used as the support, the same glossiness, touch feeling as ordinary photographic prints,
You can get the texture.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of a method for preparing a dispersion liquid used in the method of the present invention.

FIG. 2 is an explanatory diagram showing another example of a method for preparing a dispersion liquid used in the method of the present invention.

FIG. 3 is a side view showing an example of an inkjet recording medium manufactured by the method of the present invention.

[Explanation of symbols]

 1a, 1b, 1c Raw material liquid supply passage 2a, 2b, 2c Raw material liquid 3 Support 4 Ink receiving layer

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technology display location // D21H 19/38 D21H 1/22 B (72) Inventor Hiroyuki Sugada 3-30-2 Shimomaruko, Ota-ku, Tokyo No. Canon Inc.

Claims (5)

[Claims] 1. A step of preparing a dispersion liquid of alumina hydrate by colliding high-speed flows of a plurality of raw material liquids containing alumina hydrate with each other, and coating the prepared dispersion liquid on the surface of a sheet-shaped support. And a step of forming an ink receiving layer on the surface of the support by post-drying. 2. The collision pressure of the high speed flow is 5 to 1500 kg /
The method for producing an inkjet recording medium according to claim 1, wherein the method is cm ² . 3. The method for producing an inkjet recording medium according to claim 1, wherein the content of the alumina hydrate in the dispersion is 0.5 to 40 g with respect to 100 g of the solvent. 4. The total pore volume of the ink receiving layer is 0.1 to 10.
1.0 ml / g, BET specific surface area of 20-450 m ²
It is / g, The manufacturing method of the inkjet recording medium of Claim 1. 5. An ink jet recording medium manufactured by the method according to any one of claims 1 to 4.