JP2000309160A - Ink jet recording medium and recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording medium which shows outstanding recording quality such as print density or ink absorption, good image conservation (light-fastness and moisture resistance) and further, a superb surface strength making a recorded image hardly peelable. SOLUTION: This ink jet recording medium comprises a water-soluble resin and an emulsion resin as a binder resin of an ink receiving layer, and the water- soluble resin to be used is an ethylene-polyvinyl acetate emulsion resin or an aqueous polyurethane resin emulsion, an acrylate ester or a methacrylate ester as a partially saponified PVA emulsion resin. In addition, the ink receiving layer containing a light-fastness improver (a water-soluble metallic salt, a cationic dye fixing agent) is applied on a support to prepare the ink jet recording medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium, and more particularly to a recording medium having a high print density, being clear, having excellent ink absorption, and having good surface strength, light resistance, room storage stability, and water resistance. The present invention relates to an ink jet recording medium which does not cause a decrease in density or a change in color tone with respect to direct sunlight (sunlight) or indoor light, has a high ink absorption speed, and can sufficiently cope with future high-speed printing.

[0002]

2. Description of the Related Art Inkjet printers have been increasingly used in recent years because of their features such as clearness of recording, quietness of sound, and ease of colorization. In this ink jet printer, it is necessary to use ink that is difficult to dry in order to prevent nozzle clogging due to drying of the ink. In general, as an ink having this property,
Water-soluble inks in which dyes, solvents, additives, and the like are dissolved or dispersed in water are used. However, characters and images formed on a recording medium using a water-soluble ink are more resistant to light, water, and moisture (ex. It does not discolor or discolor even if it is), and is inferior from the standpoints of indoor storage stability and storage stability against direct sunlight.

In recent years, as ink-jet printers have become inexpensive and their clarity and color have become familiar, demands for various properties such as light fastness of recorded images and surface strength of ink-jet recording media have been gradually increased. It is becoming. Therefore, it is the present condition that the complete securing of these properties such as light resistance and surface strength is now an essential condition of the ink jet recording medium.

[0004]

However, in the conventional ink jet recording medium, although proposals have been made to improve the light fastness of recording of characters and images, especially full-color recording, it is still insufficient. Further, the recording medium is formed with an ink receiving layer containing a large amount of a pigment component having excellent ink absorbability, and the strength of the ink receiving layer is reduced because the amount of ink used for full-color recording is increased. If the pigment is dropped off or the ink receiving layer is peeled off due to rubbing or bending the surface, there is a problem with respect to the surface strength that was performed. In particular, when the surface strength is low, there is a problem in that a recorded image may be missing (referred to as jagged) due to a conveying roller during inkjet recording. Therefore, the present invention has been made in view of the above-described situation in the related art, and has excellent ink jet recording characteristics, and has excellent light resistance and a surface strength with which a recorded image is not easily peeled off. It is intended to provide a medium for use.

[0005]

As a result of various studies on the ink jet recording medium, the present inventor has found that an ink receiving layer containing, as a binder, an emulsion resin mixed with a water-soluble resin at an arbitrary ratio is provided. Has been found to be extremely effective in improving the surface strength of the inkjet recording medium. Therefore, the ink jet recording medium of the present invention has been made based on the above findings, and the binder resin of the ink receiving layer contains a binder resin obtained by mixing a water-soluble resin and an emulsion resin in an arbitrary ratio. Features. Hereinafter, preferred embodiments of the present invention will be described in detail.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The ink jet recording medium of the present invention has a layer structure in which at least one ink receiving layer is provided on at least one surface of a substrate by a laminating means such as a coating method. The gloss adjusting layer may be provided on the ink receiving layer. Hereinafter, the materials constituting the base material, the ink receiving layer and the glossiness adjusting layer will be described.

(1) Substrate The substrate on which the ink receiving layer and the back coat layer used in the present invention are applied is a chemical pulp such as LBKP or NBKP, G
Mechanical pulp such as P, PGW, RMP, TMP, CTMP, CMP, CGP,
Various additives commonly used in papermaking, such as pigments and sizing agents, fixing agents, retention agents, paper strength agents, etc., mainly composed of wood pulp such as waste paper pulp such as DIP, and synthetic fiber pulp such as polyethylene fiber. Mixing agents as needed, into fourdrinier paper machine, round paper machine, base paper manufactured by various devices such as twin wire paper machine, and further into base paper,
Use size paper with starch or polyvinyl alcohol, or base paper provided with an anchor coat layer, or coated paper such as art paper, coat paper, or cast coat paper provided with a coat layer thereon. be able to. Such base paper and coated paper may be provided with the ink receiving layer as it is, even if a calender such as a machine calender, TG calender, or soft calender is used which is smoothed before the ink receiving layer coating. good.

As the base material, a polyolefin resin layer may be provided on the above-mentioned base paper, and a film material of a synthetic resin such as polyethylene, polypropylene, polyester, nylon, rayon, polyurethane or a mixture thereof, A medium material formed by forming a resin into fibers can also be used.

(2) Ink-receiving layer (a) Binder resin Water-soluble resin In the present invention, a water-soluble resin can be used as a binder resin contained in the ink-receiving layer. For example, polyvinyl alcohol, vinyl acetate, oxidized starch, Examples include etherified starch, cellulose derivatives such as carboxymethylcellulose and hydroxyethylcellulose, casein, gelatin, soybean protein, and silyl-modified polyvinyl alcohol. Among them, partially saponified PVA and carboxylic acid-modified PVA are preferable because they have good adhesiveness and satisfy light resistance and moisture resistance. In particular, the degree of saponification of these PVAs is 73.0 to 85.0 mol%. Are more preferred.

Emulsion Resin In the present invention, as the binder resin contained in the ink receiving layer, a water-soluble resin and an emulsion resin can be used alone or in combination of two or more. As the emulsion resin, it is particularly preferable to use an acrylic resin such as an ethylene-vinyl acetate copolymer emulsion resin, an aqueous urethane resin, an acrylate ester or a methacrylate ester polymer or a copolymer. The characteristics of each emulsion resin are preferably those satisfying any of the following conditions, and more preferably satisfying all the following conditions.

<Ethylene-vinyl acetate emulsion resin> (1) A partially saponified PVA is used as an emulsion stabilizer. (2) Tg when formed into a film is −30 ° C. to −5 ° C. (3) The ionicity is nonionic or weakly anionic.

<Aqueous urethane resin> (1) A suspension comprising ionomer resin particles of a copolymer of an isocyanate and a polyol having a cationic substituent dispersed therein. (2) The ionicity is cationic. (3) Tg in the form of a film is -30C to 0C. (4) Partially saponified PVA is used as an emulsion stabilizer.

<Acrylic Emulsion Resin> (1) At least one component of an acrylic ester or a methacrylic ester having a cationic substituent is copolymerized. (2) The ionicity is cationic. (3) Partially saponified PVA is used as an emulsion stabilizer.

The proportion occupied by the emulsion resin as a whole binder in the ink receiving layer is 5 to 5 by weight.
50% by weight is preferred. The binder resin is preferably 20 to 50% by weight of the total solid content of the ink receiving layer, and the emulsion resin is preferably 1 to 25% by weight. In particular, 1 to 20% by weight is suitable.

(B) Pigment In the ink receiving layer of the present invention, one or more commonly used pigments which are insoluble or hardly soluble in water can be used. For example, light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate,
Satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica, colloidal alumina, pseudoboehmite, aluminum hydroxide, alumina, lithopone, zeolite, hydrohalosite, magnesium carbonate, magnesium hydroxide, etc. White inorganic pigments, styrene-based plastic pigments, acrylic-based plastic pigments, and organic pigments such as polyethylene, urea resins, and melamine resins.

Among the above, as the white pigment contained as a main component in the ink receiving layer, a porous inorganic pigment is preferable because the ink jet ink is excellent in drying property and absorptivity, etc. , Porous magnesium carbonate, porous alumina and the like. Among these, in the present invention, the specific surface area of about 200 to 600 g / m ² that satisfies both the printing quality and the storability (water resistance, abrasion resistance, light resistance, indoor storability, and storability against direct sunlight). It is preferred to use sedimentation type and gel type porous amorphous silica.

The mixing ratio of the pigment and the binder resin in the ink receiving layer is as follows: binder resin: pigment = 1: 1 by weight.
The ratio is preferably from 1: 1 to 1:15, particularly preferably from 1: 2 to 1:10.

(C) Light fastness improver A water-soluble metal salt compound or a cationic dye fixing agent can be added to the ink receiving layer in order to improve the light fastness and various properties of the image. Note that these 2
It is more effective to combine the components. In the present invention, the term “water-soluble” means that when a saturated aqueous solution of a metal salt is prepared using water at 20 ° C. as a solvent, the mass of the inorganic metal salt contained in 100 g of the saturated aqueous solution is 1 g or more in terms of anhydrous mass. In the present invention, among such water-soluble metal salt compounds, a metal salt compound which generates a divalent or higher cation ion when dissolved in water or the like and ionized is particularly preferable. Specific examples of excellent effects include magnesium chloride, calcium chloride, barium chloride, tin chloride, lead chloride, magnesium sulfate, calcium sulfate, magnesium chlorate, magnesium phosphate, magnesium nitrate, barium nitrate, and calcium nitrate. Is mentioned. The content of these metal salts may be any ratio to the total solid content of the ink receiving layer, and is preferably 1.0% to 40.0% by weight, and more preferably 5.0% to 20.0% by weight. % Is most preferred.

As the cationic dye fixing agent, a polyamine resin is preferably used. Specifically, polyvinyl benzyl trimethyl ammonium halide, poly diacryl dimethyl ammonium halide, poly dimethyl amino ethyl methacrylate hydrochloride, polyethylene imine, dicyan diamide formalin condensate , Epichloropidrin-modified polyalkylamines, polyvinylpyridinium halides, and polyethyleneimine quaternary ammonium salts. Even when used alone, they have a sufficient effect of improving light fastness. However, when used in combination with the above-mentioned divalent or higher-valent water-soluble metal salt, a synergistic effect is obtained, which is preferable. In order to achieve both the surface strength (jagging) and light resistance in the present invention and to improve the effectiveness thereof, the ratio of the solid content in the ink receiving layer of the cationic dye fixing agent to the water-soluble metal salt having a valency of 2 or more is required. Is preferably from 4: 1 to 1: 4, and most preferably from 3: 2 to 1: 1.

(D) Additives In the ink receiving layer, other additives such as a pigment dispersant, a thickener, a flow improver, an antifoaming agent, a foam inhibitor, a release agent, a foaming agent, A penetrant, a coloring dye, a coloring pigment, a fluorescent brightener, an antioxidant, an ultraviolet absorber, a preservative, a water-proofing agent, a hardener, and the like can be appropriately compounded as required.

(E) Formation of Ink Receiving Layer The ink receiving layer is formed by dissolving or dispersing the above-mentioned material for forming the layer in water or an appropriate solvent such as alcohol in which the material is dissolved to prepare a coating liquid. By using various devices such as various blade coaters, roll coaters, air knife coaters, bar coaters, rod blade coaters, and size presses as appropriate on or off-machine,
It is formed by coating on a substrate. The ink absorbing layer may be provided as a single layer or as two or more layers. When two or more layers are provided, the emulsion resin may be contained in each layer or may be contained only in the surface layer.

The coating amount of the ink receiving layer is, for example,
First, for a one-layer type, 5 to 30 g / m ² is preferable. When a first ink receiving layer is laminated on a base material and a second ink receiving layer is laminated on the first ink receiving layer to form a two-layer type, the coating amount of the first ink receiving layer is 5 preferably to 30 g / m ^2, in particular 5 to 20 g / m ² is preferred. The coating amount of the second ink receiving layer is preferably 5 to 15 g / m ² , and more preferably 5 to 1 g / m ^2.
0 g / m ² is preferred. If the coating amount is less than this range, sufficient ink absorbency and fixability may not be obtained, and if it is too large, problems such as powder dropping, productivity reduction, and cost increase may be caused. In particular, when the coating amount of the second ink receiving layer is more than 15 g / m ^2, it becomes difficult for the ink to pass through the second ink receiving layer, which may cause bleeding and impair the sharpness of the image. is there. It is preferable to control the coating amount of the ink receiving layer according to the number of the ink receiving layers to be laminated as described above. When two or more ink receiving layers are laminated, the metal salt may be contained in any one of the ink receiving layers, or may be contained in a plurality of ink receiving layers. Here, when a metal salt is added to a plurality of ink receiving layers, it is more preferable that the content of the metal salt be the same in order to further reduce the concentration gradient between the layers.

After application of the ink receiving layer, finishing may be performed using a calendar such as a machine calendar, a TG calendar, a super calendar, and a soft calendar.

(3) Glossiness Adjusting Layer In the present invention, a glossiness adjusting layer containing a binder resin and a pigment can be provided on the above-mentioned ink receiving layer. This glossiness adjustment layer adjusts the glossiness to make high gloss paper,
Medium gloss paper, fine gloss paper, etc. can be made separately. It also has the effect of preventing ink from being soaked and improving the optical density and saturation. As the binder resin for forming the glossiness adjusting layer, a water-soluble resin that can be used in combination with the ink receiving layer can be appropriately used. In addition, in order to improve recording characteristics such as ink absorbency, it is preferable to use the pigment used in the ink receiving layer described above together with the binder resin in the glossiness adjusting layer. Among them, colloidal silica is excellent in dispersibility and stable in paint. This is particularly preferable because the effect of improving the productivity and the productivity can be obtained.

In addition to the above binder resin and pigment, additives for improving the light fastness and various characteristics of the image used in the ink receiving layer may be appropriately added to the material for forming the glossiness adjusting layer, if necessary. can do. The blending ratio of the binder resin and the pigment in the glossiness adjusting layer is preferably from 5:95 to 30:70, more preferably from 5:95 to 20:80 by weight ratio.

The gloss adjusting layer is prepared by dispersing and dissolving the above-mentioned materials in a suitable solvent such as water or an organic solvent to prepare a coating liquid, and applying the coating liquid on the ink receiving layer by the same operation as the ink receiving layer. It can be formed by drying. The coating amount of the glossiness adjusting layer is 5 to 2 in the case of directly applying to the substrate.
0 g / m ² is preferred. Further, when laminated on the ink receiving layer, the coating amount is preferably from 5 to 15 g / m ² , particularly from 5 to 10 g / m ^2.
g / m ² is preferred. If the coating amount is more than 15 g / m ^2, it will be difficult for the ink to pass through the glossiness adjusting layer, causing bleeding and impairing the sharpness of the image. Further, the glossiness adjusting layer may be finished using a calender such as a machine calender, a TG calender, a super calender or a soft calender after coating.

[0027]

Next, examples based on the present invention and comparative examples will be shown to clarify the effects of the present invention. In each of the Examples and Comparative Examples, the base material was a high-quality paper having a basis weight of 90 g / m ² , and a coating solution in which a material having the following composition was dissolved and dispersed in water was sequentially applied to one surface of the base material and dried. In this way, an ink receiving layer and a glossiness adjusting layer are laminated and provided to form an ink jet recording medium. Listed in the examples are percentages of dry solids weight. The coating amount was 10 g / m ^{2 for} both the ink receiving layer and the glossiness adjusting layer unless otherwise specified.

<Example 1> [Ink receiving layer] Binder resin Partially saponified PVA Kuraray Co., Ltd .: Kuraray Poval PVA-317 30% by weight Vinyl acetate-ethylene emulsion resin Kuraray Co., Ltd .: Panflex OM-5500 5% by weight -White pigment: Silica Tokuyama: Fine Seal X-37B 45% by weight-Light fastness improver: Tomita Pharmaceutical: Magnesium chloride S (water-soluble metal salt) 10% by weight Senka: HP-134A (fixing cationic dye) Agent) 10% by weight [Glossiness adjusting layer] Binder resin Maleic acid-modified saponified PVA Nippon Gohsei: 10% by weight Gosenal T-350 10% Colloidal silica Nissan Chemical Industries: Snowtex UP 90% by weight <Implementation Examples 2-3, Comparative Examples 1-3> Materials similar to those of the ink receiving layer described in Example 1 were used. The ink jet recording media of Examples 2 to 3 and Comparative Examples 1 to 3 of the present invention were obtained in the same manner as in Example 1 except that the mixing ratio was changed as shown in Table 1.

Example 4 Ink Receiving Layer Binder Resin Partially Saponified PVA Kuraray Co., Ltd .: Kuraray Poval PVA-317 30% by weight Acrylic resin emulsion Shin-Nakamura Chemical Co., Ltd .: NK Polymer AC-8 5% -White pigment silica Tokuyama: Fine Seal X-37B 45% by weight-Lightfastness improver: Tomita Pharmaceutical: Magnesium chloride S (water-soluble metal salt) 10% by weight Senka: HP-134A (cationic dye) Fixing agent) 10% by weight [Glossiness adjusting layer] Same as in Example 1.

<Examples 5 to 6 and Comparative Example 4> The same materials as in the ink receiving layer described in Example 4 were used, and the blending ratio was changed as shown in Table 1 in the same manner as in Example 4. Inkjet recording media of Examples 5 to 6 and Comparative Example 4 of the present invention were obtained.

<Example 7> [Ink receiving layer] Binder resin partially saponified PVA Kuraray Co., Ltd .: Kuraray Poval PVA-317 30% by weight Water-based urethane resin Asahi Denka Co., Ltd .: Adeka Bontiter HUX-680 5% by weight White Pigment Silica Tokuyama Co., Ltd .: Fine Seal X-37B 45% by weight-Light fastness improver Tomita Pharmaceutical Co., Ltd .: Magnesium chloride S (water-soluble metal salt) 10% by weight Senka Co., Ltd .: HP-134A (cationic dye fixing agent) 10% by weight [Gloss adjustment layer] Same as in Example 1.

<Examples 8 to 10> The present invention was carried out in the same manner as in Example 7 except that the same materials as used in the ink receiving layer described in Example 7 were used and the mixing ratio was changed as shown in Table 1. The ink jet recording media of Examples 8 to 10 were obtained.

Comparative Example 5 [Ink receiving layer] Binder resin Partially saponified PVA Kuraray Co., Ltd .: Kuraray Poval PVA-317 25% by weight polyester emulsion resin Dainippon Ink & Chemicals, Inc .: Finetech ES-22 25% by weight ・ White pigment silica Tokuyama: Fine Seal X-37B 30% by weight ・ Light fastness improver: Tomita Pharmaceutical: Magnesium chloride S (water-soluble metal salt) 10% by weight Senka: HP-134A (cation) 10% by weight [Glossiness adjusting layer] Same as in Example 1.

These are shown in Table 1.

[0035]

[Table 1]

Next, the above Examples 1 to 10 and Comparative Examples 1 to 5
Commercially available ink-jet printer (manufactured by Seiko Epson, PM-770)
Using C), a printed image was obtained by printing an evaluation target such as a color patch on the glossiness adjusting layer with an aqueous ink. Using the image obtained in this way, the surface strength (jagged), light resistance,
An evaluation of the moisture resistance was performed.

[Evaluation Method] <Zeeding> Solid printing was performed on the obtained ink jet recording medium using the above-mentioned printer, with a black optical density of 1.0, and this was caused by the lack of a recorded image by the conveying roller. The indentation was evaluated according to the following evaluation criteria. A: Practically excellent without any problem (no omission is observed). B: Excellent without practical problems (slight dents and the like are observed on the surface, but the image quality of the recorded image does not deteriorate). C: Excellent without practical problems (at least part of the recorded image is missing).

<Light resistance 1 (xenon lamp accelerated test)>
Xenon weatherometer (ATLAS, Ci-50
00) and Bk, Y, M, C, R, G,
Solid printing of B was performed using the printer. For the inkjet recording medium of each example and each comparative example,
Black panel temperature 35 ° C, relative humidity 60%, 340n
An exposure test of 30 KJ / m ² was performed at a UV irradiation intensity of 0.18 W / m ² . Then, using a spectrophotometer (GRETAG SPM50, manufactured by Gretag Macbeth), the optical density of each color patch printed on these recording media was measured before and after the exposure test, whereby the residual ratio of the optical density after the exposure test was measured. (%) Was evaluated and the light resistance was evaluated according to the following evaluation criteria. A: The residual ratio of the optical density exceeds 90%. B: The residual ratio of the optical density is more than 80% and less than 90%. C: The residual ratio of the optical density is more than 70% and less than 80%. D: The residual ratio of the optical density is less than 70%.

<Light Resistance 2 (Fluorescent Lamp Acceleration Test)> Using a fluorescent lamp accelerometer (HPUV, manufactured by ATLAS), Bk, Y, M, C, R, G, and B having an optical density of 1.0 were used. Solid printing was performed using the printer. About 6 W / m ² (300) for the ink jet recording medium of each example and each comparative example.
The exposure test was performed by irradiation with only a white fluorescent lamp for 100 hours in an ultraviolet wavelength range from 400 nm to 400 nm). Then
Spectrophotometer (GRETAG S, manufactured by Gretag Macbeth)
Using PM50), the optical density of magenta of these recording media was measured in the same manner as in the xenon lamp acceleration test of light fastness 1 to evaluate light fastness according to the following evaluation criteria. A: The residual ratio of the optical density exceeds 90%. B: The residual ratio of the optical density is more than 80% and less than 90%. C: The residual ratio of the optical density is more than 70% and less than 80%. D: The residual ratio of the optical density is less than 70%.

<Moisture Resistance> Using a thermo-hygrostat, the ink-jet recording medium of each of the examples and comparative examples was
An exposure test was performed at 32 ° C. and a relative humidity of 85% for 3 days.
Thickening of thin line of each color (Bk, Y, M, C, R, G, B), thinning of white line (white outline) in each color, blurring of image outline and color patch (Bk, Y, M, C, R, G, and B) were evaluated based on the discoloration of the optical density of 1.0. In particular, regarding discoloration of a color patch, a spectrophotometer (Gretag Macbeth, G
Using RETAG SPM50), the recording medium was measured before and after the exposure test to determine the residual ratio (%) of the optical density after the exposure test, and the moisture resistance was evaluated according to the following evaluation criteria. A: The residual ratio of the optical density exceeds 90%. B: The residual ratio of the optical density is more than 80% and less than 90%. C: The residual ratio of the optical density is more than 70% and less than 80%. D: The residual ratio of the optical density is less than 70%.

Table 2 shows the evaluation results.

[0042]

[Table 2]

From the above results, in Examples 1 to 10, the print density, clarity, and ink absorbency, which are essential conditions for the ink jet recording medium, are extremely high, and the light resistance, particularly, the decrease in density and the color tone with respect to indoor storage stability. An ink jet recording medium with little change was obtained.

In Examples 1 to 3 and Comparative Examples 1 to 3, the mixing ratio was changed by using a vinyl acetate-ethylene emulsion resin, but when the amount of the emulsion resin in the total amount of the binder resin was 5 to 50% by weight, The result was that the knurling was improved and at the same time high lightfastness could be maintained. In Comparative Example 1, there was no emulsion resin, so that the crenellation was not improved. In Comparative Example 2, since the emulsion resin was used alone, the ink absorbency was poor. Further, Examples 4 to 6 using an acrylic emulsion resin
In Comparative Example 4, similar results were obtained. Good results were obtained also in Examples 7 to 10 using the urethane-modified emulsion resin. In addition, in the emulsion resin used in Comparative Example 5, the knurling was improved, but the light resistance was not accompanied. As described above, by using these selected emulsion resins and adding a light resistance improver, it is possible to improve the surface strength (graining) and maintain high moisture resistance while maintaining high light resistance. An ink jet recording medium was obtained.

As in the above embodiment, the present invention is realized by adding an emulsion resin. At this time, it was confirmed that if the Tg of the emulsion resin was selected from -30 ° C to 0 ° C, an ink jet recording medium having well-balanced coating properties, light resistance, ink absorbency, etc. could be obtained. In particular, in the case of vinyl acetate-ethylene emulsion resin, the range of -30 ° C to -5 ° C was more preferable. In addition, it was confirmed that even when two or more kinds of the emulsion resins described in the above examples were used in combination, there was no decrease in light resistance and the knurling was improved.

[0046]

As described above, according to the present invention, good binder resin of the ink receiving layer of the ink jet recording medium contains at least a water-soluble or water-dispersible resin and an emulsion resin. An ink jet recording medium having excellent ink jet recording characteristics capable of obtaining a clear image without bleeding due to ink absorption and exhibiting excellent light resistance and surface strength (jagged) is obtained. In addition, in the present invention, by using the specific emulsion resin as described above, the moisture resistance such that discoloration or fading of an image does not occur even when the recording characteristics are left for a long time under high temperature and high humidity is improved.

Continued on the front page (72) Inventor Hiroyuki Onishi 3-3-5 Yamato, Suwa City, Nagano Prefecture Inside Seiko Epson Corporation (72) Inventor Jun Sugiyama 3-3-5 Yamato Suwa City, Nagano Prefecture Inside Seiko Epson Corporation (72) Inventor Takayuki Ishikawa 3-1 Yomoe-cho, Shizuoka City, Shizuoka Prefecture Inside the Paper Division of Hamakawa Paper Mill Co., Ltd. (72) Inventor Nobuhiro Kubota 3-1 Yomoe-cho, Shizuoka City, Shizuoka Prefecture Inside the Tosho Paper Division (72) Takeshi Yoshimoto, Inventor 3-1 Yomibacho, Shizuoka-shi, Shizuoka Prefecture Inside the Paper Division of Hamakawa Paper Mill Co., Ltd. (72) Shigeru Asai 3-1 Yomibacho, Shizuoka-shi, Shizuoka No. Within the Western Paper Division of Hamakawa Paper Mills Co., Ltd. (72) Minoru Tsuchida No. 3-1, Yosoba Tomoecho, Shizuoka-shi, Shizuoka Prefecture Inside of the Western Paper Division of Hamakawa Paper Mills Co., Ltd. 3-1, Machimachi Paper Machinery Co., Ltd. Western Paper Division F-term (reference) 2C056 EA13 FC06 2H086 BA12 BA15 BA31 BA33 BA34 BA38 BA41 4F100 AA07B AA19B AA20B AK01B AK24B AK51B AK68B AK71B AR00B AR00C AS00B AT00A BA02 BA03 BA05 BA06 BA10A BA10C BA13 CA05B CA13B JJJJJJJJBJJBJJBJ90B14 AG71 AG85 AG94 AG97 AH02 AH25 AH33 AH37 AH50 AJ04 BE09 EA20 EA32 FA11 FA13 FA15 FA19 FA30 GA09

Claims (15)

[Claims] 1. An ink jet recording medium provided with an ink receiving layer comprising a pigment and a binder resin on at least one surface of a substrate, wherein both a water-soluble resin and an emulsion resin are used as the binder resin of the ink receiving layer. An ink jet recording medium, wherein the emulsion resin is a nonionic or weakly anionic ethylene-vinyl acetate emulsion resin. 2. An ink jet recording medium provided with an ink receiving layer comprising a pigment and a binder resin on at least one surface of a substrate, wherein a water-soluble resin and a cationic substituent are used as the binder resin of the ink receiving layer. An ink-jet recording medium characterized by containing both an aqueous urethane resin which is a suspension obtained by dispersing ionomer resin particles of a copolymer of isocyanate and polyol having the following. 3. An ink jet recording medium provided with an ink receiving layer comprising a pigment and a binder resin on at least one surface of a substrate, wherein the binder resin of the ink receiving layer is a water-soluble resin, and a cation is formed on an ester group. An ink jet recording medium comprising: an acrylic ester-based emulsion resin having at least one component of an acrylate or a methacrylate having a functional substituent as a copolymerization component. 4. The ink jet recording medium according to claim 1, wherein partially saponified PVA is used as an emulsion stabilizer. 5. The ink jet recording medium according to claim 1, wherein an emulsion having a Tg of the resin of −30 ° C. to 0 ° C. is used. 6. A binder resin for an ink receiving layer,
Water-soluble resin, vinyl acetate-ethylene, urethane,
2. An emulsion resin comprising at least two types of emulsion resins selected from acrylic and methacrylic types.
6. The ink jet recording medium according to any one of items 1 to 5. 7. The ink jet recording medium according to claim 1, wherein the amount of the emulsion resin in the total amount of the binder resin in the ink receiving layer is 5 to 50% by weight. 8. The method according to claim 7, wherein the amount of the emulsion resin is 1 to 25% by weight of the whole ink receiving layer.
3. The ink jet recording medium according to claim 1. 9. The ink jet recording medium according to claim 1, wherein the pigment is silica and / or alumina. 10. An ink receiving layer comprising a water-soluble divalent or higher valent metal salt as a light fastness improver and a cationic dye fixing agent.
The inkjet recording medium according to claim 1, further comprising a component. 11. The lightfastness improving agent is magnesium chloride,
The inkjet recording medium according to claim 10, comprising at least one water-soluble metal salt selected from magnesium sulfate and calcium chloride. 12. The amount of the light fastness improver based on the whole of the ink receiving layer is from 1.0% by weight to 40.0% by weight, more preferably from 5.0% by weight to 20.0% by weight. 13. The ink jet recording medium according to claim 11, wherein: 13. The cationic dye fixing agent in the ink receiving layer has a solid content ratio of 4: 1 to 1: 4 with respect to a divalent or higher valent water-soluble metal salt. 12
3. The ink jet recording medium according to claim 1. 14. The ink jet recording medium according to claim 1, further comprising a glossiness adjusting layer on the outermost surface of said ink receiving layer. 15. An ink jet recording method comprising a combination of the ink jet recording medium according to claim 1 and a water-based ink.