JPH08338000A - Recording medium and inkjet recording method using the same - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose is to satisfy well-balanced requirements described above for recording with water-based inks, especially for ink jet recording, and to have good surface glossiness, and to achieve higher ink absorption. PROBLEM TO BE SOLVED: To provide a recording medium capable of recording with a property and an image density, and an inkjet recording method using the recording medium. [Structure] A base paper mainly composed of fibrous pulp and filler is coated with a coating liquid containing a pigment, a cationic substance and a heat-sealable resin emulsion, and the obtained coating layer is a heat-sealable resin. The heat treatment is performed at or near the lowest film forming temperature to form a coating layer, and the surface of the coating layer is subjected to gloss treatment to obtain a recording medium.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to recording with an aqueous ink,
In particular, the present invention relates to a recording medium which has a good balance of recording characteristics in inkjet recording, has good surface glossiness, and can achieve high ink absorption and high image density, and an inkjet recording method using the recording medium.

[0002]

2. Description of the Related Art Conventionally, as a recording medium used for forming an image by an ink jet recording method, Japanese Patent Publication No. 3-2666 is known.
As described in JP-A-5-36237, recording paper in which a coating layer containing a finely divided silica and a water-soluble binder such as polyvinyl alcohol is provided on a base paper as described in JP-A-5-36237. Glossy paper having a film mainly composed of a water-soluble resin formed on an opaque substrate such as synthetic paper has been used. Further, JP-A-63-265680 describes a cast-coated paper for inkjet recording in which a coating layer mainly containing silica and a binder is formed by a casting method.

[0003]

In recent years, speeding up of recording,
With the improvement of inkjet recording device performance such as multi-color, in order to obtain an image that satisfies various characteristics such as resolution and density in a well-balanced manner, inkjet recording media are required to have higher and wider characteristics. Has been done.
Such characteristics include, for example, (1) high ink absorption capacity and fast ink drying, (2) high optical density of ink dots, and no blur around dots.
(3) The dot shape is close to a perfect circle and its periphery is smooth, (4) There is no uneven density in the solid print portion, and the optical density of the image is uniform, (5) Different color inks are adjacent to each other. Even if printed, the boundary is clear and bleeding does not occur, and (6) the image has good water resistance, moisture resistance, light resistance, etc., and the image is stable for long-term storage and does not deteriorate. The characteristics can be mentioned.

Further, various studies have been made for forming an image of high resolution and high density such as a silver salt photograph by an ink jet recording method. As one of the means for obtaining an image quality comparable to that of a silver salt photograph, while maintaining recording characteristics such as ink absorbency, fixing property of a recording agent in ink, water resistance of an image, and coloring property in color recording, the surface There is a method of further improving the glossiness and the image density.

However, the surface of the coated paper described in Japanese Patent Publication No. 3-26665 is matte and is not suitable for applications requiring gloss. Further, the glossy paper described in Japanese Patent Publication No. 5-36237 is capable of forming a high-gloss, high-density image, but on the other hand, since the ink receiving layer is a hydrophilic resin film, There is a problem that the drying and fixing of the adhered ink is slow and the printed portion after printing (after applying the ink) is sticky forever, which hinders continuous recording. Further, in this glossy paper, since the ink absorption speed is slow, the movement of the ink on the paper surface is likely to occur, and there is a problem that uneven density is often generated in the solid print portion. There is also the problem of poor water resistance.

On the other hand, the ink jet cast coated paper described in Japanese Patent Laid-Open No. 63-265680 is good in terms of ink drying / fixing property, but has durability such as water resistance and moisture resistance of an image, or There is a problem that the color developability is insufficient.

The present invention has been made to solve the above problems in the prior art, and its purpose is to:
A recording medium capable of recording with water-based ink, in particular, satisfying the above-mentioned various required characteristics in ink jet recording in good balance, having a good surface gloss, and capable of recording with high ink absorbency and high image density. An object is to provide an inkjet recording method using the recording medium.

[0008]

The recording medium of the present invention which can achieve the above object has a coating layer containing a pigment, a binder and a cationic substance on a base paper mainly composed of fibrous pulp and a filler. However, the surface of the coating layer is a gloss-treated recording medium, and the binder is heat-fusion resin particles.

In the recording medium of the present invention, by using the heat-fusible resin particles as the binder, it is possible to bind the pigment particles by point contact without covering the entire pigment particles with the binder. A sufficient volume of voids can be formed between the pigment particles, and higher ink absorbency can be obtained. Furthermore, since the active sites on the surface of the pigment particles are not covered with the binder film, the dye adsorption ability does not decrease, and higher image density can be obtained.

The base paper in the recording medium of the present invention is mainly composed of fibrous pulp and filler, and can maintain a desired shape of the recording medium in a stable manner, and has good bonding strength with the coating layer provided on the upper part thereof. Any material can be used without particular limitation. For example, pulp materials (LBKP, NBKP
Chemical pulp, mechanical pulp, recycled paper pulp, etc.) represented by the above, etc., and fillers as the main components, and if necessary, those produced by a conventional method from raw materials containing various papermaking auxiliaries. In this case, the pulp material may be one type of chemical pulp, mechanical pulp, recycled pulp, or the like, or a combination of two or more types thereof. Examples of the filler include calcium carbonate, kaolin, talc, titanium dioxide and the like.

As the base paper, it is preferable to use non-sized paper because it has a sufficient ink absorption capacity and ink absorption speed.

The basis weight of the base paper can be appropriately selected within a range where desired rigidity and the like can be obtained. For example, the upper limit is 200 g.
/ M ² is preferable. The lower limit is, for example, 50
It is set to g / m ² .

The coating layer provided on the base paper contains at least a pigment, a binder and a cationic substance.

As the pigment used for forming the coating layer, for example, silica, alumina, aluminum silicate, magnesium silicate, basic magnesium carbonate, talc, clay, hydrotalcide, calcium carbonate, titanium oxide, zinc oxide, etc. Inorganic pigments such as: plastic pigments made of polyethylene, polystyrene, polyacrylate and the like can be used, and one of these can be used, or two or more of these can be used in combination. In order to form an image with higher density and higher resolution, it is preferable to use at least one selected from silica, alumina, alumina hydrate and basic magnesium carbonate.
As the particle size of this pigment, for example, a particle size in the range of 0.1 to 20 μm can be used.

As the binder, the heat fusion type resin particles are used as described above. As the resin constituting the heat-fusion resin particles, the material is not particularly limited as long as the particle shape can be maintained and the pigment particles can be bound to each other at points, and desired recording characteristics can be achieved. . Examples of such a resin include acrylic acid ester-based resins,
Polyvinyl acetate resin, polyvinyl butyral resin,
Ethylene-vinyl acetate resin, styrene-acrylic ester resin, polyolefin resin, polystyrene resin, ionomer resin, polyvinyl ether resin, polyester resin, polyamide resin, polyureta resin, butadiene rubber, acrylonitrile butadiene rubber And the like, and these can be used alone or in combination of two or more. By using these resins in the form of an aqueous emulsion, these resin particles can be present as a binder in the coating layer.
The heat-sealable resin particles have a minimum film-forming temperature (M
The FT) is preferably in the range of 80 to 140 ° C.
The particle size is preferably in the range of 0.05 to 10 μm.

Further, in forming the coating layer, a heat-fusion type resin, for example, a polyolefin resin such as acrylic resin, polyethylene or polypropylene is added to the above aqueous emulsion,
Pigment and / or heat-fusion type resin such as polystyrene resin, ethylene-acrylic acid ester copolymer, ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, polyvinyl ether, polyvinyl chloride, polyester, polyamide Alternatively, one or more powders may be used in combination. The particle size of these pigments or powders may be in the range of 0.1 to 100 μm. The lower limit is preferably 0.2 μm and the upper limit is preferably 50 μm. When these are used in combination, it is preferable to use one having an MFT lower than the minimum film forming temperature (MFT) of the resin constituting the above aqueous emulsion.

The lower limit of the blending ratio of the binder to the pigment is, for example, pigment / binder = 10/1 by weight, preferably 5/1. The upper limit of the binder is, for example, pigment / binder = 1 by weight. / 2, preferably
It is set to 1/1.

The binder and cationic substance used to form the coating layer are conveniently water-soluble, but may be provided as a dispersion such as a latex or emulsion.

In order to incorporate the cationic substance into the coating layer, a method of incorporating the cationic substance into the material for forming the coating layer, a method of cationizing the above binder, and the like can be used. The cationic substance contained in the coating layer acts as a fixing agent for the recording agent component in the ink, and good water resistance and moisture resistance can be obtained due to the presence of the cationic substance.

The following can be exemplified as the cationic substance. (I) Salts such as polyallylamine hydrochloride, polyaminesulfone hydrochloride, polyvinylamine hydrochloride and chitoacetate, (II) dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, diethylaminoethyl methacrylate, Methylethylaminoethyl acrylate, methylethylaminoethyl acrylate, dimethylaminostyrene, diethylaminostyrene and methylethylaminostyrene, etc., cationic monomers having a tertiary amine in the side chain, and quaternary ammonium base derived from these monomers. A homopolymer of one kind of monomer selected from monomers having a side chain, or a copolymer of two or more kinds of these monomers, (III) a copolymer of the monomer (II) with another monomer Examples of the copolymer of ammonium quaternary salt and other monomer include copolymers of vinylpyrrolidone and aminoalkyl alkylate quaternary salt, and acrylic amide. Examples thereof include a copolymer with an aminomethyl acrylate quaternary salt. However, it is not limited to the above.

The binder and the cationic substance used for forming the coating layer are conveniently water-soluble, but may be provided as a dispersion such as latex or emulsion.

Further, the amount of the cationic substance compounded is preferably in the range of 0.01 to 7 g / m ² . 0.01
If it is less than g / m ² , water resistance becomes insufficient, and 7
If it exceeds g / m ² , the light resistance may deteriorate. A more preferable range is 0.1 to 3 g / m ² .

The coating layer is, if necessary, a melamine resin,
Glyoxal, crosslinking agents such as isocyanate, surfactants, defoamers, antioxidants, optical brighteners, ultraviolet absorbers,
It may further contain a dispersant, a viscosity adjusting agent, a pH adjusting agent, a fungicide, a plasticizer and the like.

According to this constitution of the coating layer, good recording characteristics for water-based ink, particularly high ink absorption and high image density can be obtained. When an ink containing a recording agent having an anionic group is used, the cationic substance in the coating layer associates with the recording agent having an anionic group in the ink to improve water resistance and moisture resistance. It will be even better.

The surface of the coating layer is subjected to a gloss treatment, and as the surface gloss, one having a 75-degree specular gloss of 45% or more measured according to JIS-Z-8741 is preferable. In order to obtain a gloss closer to that of a silver salt photograph, the 75-degree specular gloss measured according to JIS-Z-8741 is 65% or more, and the 20-degree specular gloss is 20%.
It is preferable that it is above.

The coating layer has a layer structure composed of at least two layers, and the surface layer has a structure suitable for imparting gloss. The surface layer can be provided on the coating layer mainly composed of the above pigment, binder and cationic substance. Examples of the structure of this surface layer include a surface layer mainly composed of organic resin fine particles. The surface layer mainly composed of the organic resin fine particles is one in which a part of the organic resin fine particles are fused to form a smooth or glossy surface, and if necessary, colloidal silica or the like for the purpose of improving ink absorbability or the like. It may further include the above-mentioned pigment or binder. The organic resin fine particles are not particularly limited as long as they can form a surface layer having a highly glossy surface and can obtain desired recording characteristics. For example, a latex of an acrylic polymer such as a polymer of acrylic acid ester or methacrylic acid ester or a copolymer of these monomers and another monomer, a latex of a carboxyl-modified conjugated diene copolymer, an ethylene-vinyl acetate copolymer. A latex of a vinyl-based copolymer such as a polymer, polyvinyl chloride fine particles and polyethylene fine particles, fine particles made of a copolymer of vinylpyrrolidone and styrene, and fine particles made of a copolymer of vinyl alcohol and styrene can be used.

The particle size of the organic resin particles is, for example, 0.01 μm to 5 μm, more preferably 0.05 μm.
Those having a range of m to 2 μm can be used.

Among the above-mentioned organic resin fine particles, vinylpyrrolidone-styrene copolymer fine particles and vinyl alcohol-styrene copolymer fine particles are preferable, and these copolymers are random, block or graft copolymerized. However, random and graft copolymerization are particularly preferable. Since these copolymers have a structure in the molecule that has a strong affinity for the ink, when the ink permeates through the surface layer, it is established that the recording agent component in the ink will be captured by the fine particles. Therefore, it becomes possible to form an image having high density and high moisture resistance. As a copolymer of vinylpyrrolidone and styrene, the trade name of Antara (GAF
The copolymer of vinyl alcohol and styrene can be obtained by saponifying a copolymer of vinyl acetate and styrene.

The recording medium of the present invention having the above structure is
The coating layer forming material is added, together with other additives as necessary, to a suitable solvent, for example, water, alcohol, or various organic solvents to prepare a coating solution, which is coated on a substrate. It can be obtained by working. For forming the coating layer, for example, various methods such as a roll coater method, a blade coater method, an air knife coater method, a gate roll coater method, a bar coater method, a size press method, a spray coater method, a gravure coater method, and a curtain coater method. Is available.

When a coating layer composed of a plurality of coating layers is provided, first the coating liquid for forming the first layer is applied and then dried by a conventional method to form the first layer, and then the coating liquid is formed. Further, a coating liquid for forming a second layer is applied to the above, and when finishing with the second layer, a treatment for imparting gloss to the surface of this layer is performed to finish this second layer as a surface layer. For 3 layers or more,
The formation of the lower layer is repeated by the steps of applying the coating liquid and drying, and the re-surface layer is treated to obtain surface gloss. When the coating layer is composed of one layer, a treatment for imparting gloss to the surface is performed after forming the first coating layer.

The upper limit of the coating amount of the coating layer is 40 g / m ² ,
It is preferably about 10 g / m ² . The lower limit is about 3 g / m ² .

Various methods can be used to impart gloss to the surface layer, but the casting method is preferred. Examples of the casting method include a wet casting method in which a mirror-finished surface is heated and a wet coating layer is pressure-bonded to the surface for gloss finish, and the wet coating layer is once dried and then plasticized by rewetting. It is possible to use a rewet casting method in which a heated mirror surface of the finished surface is pressure-bonded thereto for gloss finish, or a gel cast method in which the heated mirror surface of the finished surface is pressure-bonded to the wet coated surface in a gel state.

The image formation by the ink jet recording method on the recording medium of the present invention having the above constitution can be carried out, for example, as follows.

As the ink used for image formation, any ink applicable to the ink jet method can be used without limitation. For example, a recording agent for forming an image and a liquid medium for dissolving or dispersing the recording agent are essential components,
If necessary, various dispersants, surfactants, viscosity modifiers,
Specific examples thereof include those having a specific resistance adjusting agent, a pH adjusting agent, an antifungal agent, a stabilizer for dissolving or dispersing a recording agent, and the like.

Recording agents used in inks include direct dyes, acid dyes, basic dyes, reactive dyes, food dyes,
Examples thereof include disperse dyes, oil dyes, various pigments and the like, and conventionally known ones can be used without limitation. The content of the recording agent in the ink is determined according to the characteristics required for the ink and the like, but a general concentration of about 0.1 to 20% by weight can be used. As described above, when an ink containing a recording agent having an anionic group is used, the cationic substance in the undercoat layer associates with the recording agent having an anionic group in the ink to prevent water resistance. And moisture resistance are further improved.

As the liquid medium used for dissolving or dispersing the recording agent, water or a mixed solvent of water and a water-soluble organic solvent can be used. Examples of the water-soluble organic solvent include alkyl alcohols such as methanol, ethanol, isopropyl alcohol and n-butanol; amides such as dimethylformamide and dimethylacetamide;
Acetone, ketones such as acetone alcohol, keto alcohols; ethylene glycol, propylene glycol,
Alkylene glycols such as triethylene glycol, thiodiglycol, diethylene glycol, 1,2,6-hexanetriol and polyethylene glycol; glycerins; (di) ethylene glycol monomethyl (or ethyl) ether, triethylene glycol mono (or di) Alkyl ethers of polyhydric alcohols such as methyl (or ethyl) ether; sulfolane; n-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like, and one or more of them are used. It
Among these, water-miscible glycols or glycol ethers, which are effective in preventing the ink from drying in the recording head, are often used.

The recording head used in the ink jet recording method used in the image forming method of the present invention is a recording medium which is a range by ejecting ink effectively from the ejection port (orifice) provided at the tip of the ink flow path. Any method can be used as long as it can apply a small amount of ink to the ink. Among them, according to the method described in Japanese Patent Laid-Open No. 54-59936, the ink subjected to the action of thermal energy undergoes a rapid volume change in the ink flow path, and the ink is caused to act by the action force due to this state change. A method of discharging from the discharge port at the tip of the flow path can be preferably used.

An example of an ink jet recording apparatus that can be used in the ink jet recording method used in the image forming method of the present invention will be described below with reference to the drawings. 1, 2 and 3 show an example of the configuration of a recording head which is a main part of the apparatus. 1 is a sectional view taken along the ink flow path of the recording head, and FIG. 2 is a sectional view taken along the line AB of FIG. The recording head 13 has a structure obtained by adhering a plate made of glass, ceramic, plastic or the like having a groove 14 serving as an ink flow path, and a heating head 15 (the structure of the heating head is not limited to that shown in the drawing). Have. Heating head 1
In No. 5, a heat storage layer 19, a heating resistance layer 18 made of nichrome, electrodes 17-1 and 17-2 made of aluminum, and a protective layer were laminated in this order on a substrate 20 having good heat dissipation such as alumina. And the electrodes 17-1 and 17-2
By energizing the element, the portion of the heating resistor layer 18 where the electrodes are not stacked (the portion within the region indicated by n) generates heat, and thermal energy acts on the ink located above it. .

At the time of recording, the ink 21 is filled up to the ejection port (orifice) 22 which is a fine opening at the end of the groove 14, and in that state, the electrodes 17-1 and 1 are corresponding to the recording signal.
When electricity is applied to 7-2, the area indicated by n of the heat generating head 15 rapidly generates heat, and bubbles are generated in the ink 21 in contact therewith, and the pressure causes the ink 21 to drop from the ejection port 22 into small droplets 24. Are ejected and fly toward the recording medium 25.

FIG. 3 shows the appearance of a multi-head in which a large number of ink channels shown in FIG. 1 are arranged. This multi-head has a grooved plate 27 having multi-grooves 26 composed of a large number of grooves constituting ink flow paths arranged in parallel, and a heat generating region having the same structure as in FIG. 1 at a predetermined position in each groove ( n) is adhered to the heating head 28 formed so as to be arranged.

FIG. 4 shows an example of an ink jet recording apparatus incorporating the multi-head shown in FIG. In FIG. 4, reference numeral 61 denotes a plate serving as a wiping member, one end of which is held by a blade holding member to become a fixed end, which is in the form of a cantilever. The blade 61 is arranged at a position adjacent to the recording area with respect to the recording head, and in the case of this example, is held in a form protruding in the moving path of the recording head. 62 is a cap,
It is arranged at the home position adjacent to the blade 61,
The recording head is moved in a direction perpendicular to the moving direction to come into contact with the ejection port surface to perform capping. 63 more
Is an ink absorber provided adjacent to the blade 61, and like the blade 61, is held in a protruding form in the movement path of the recording head. The blade 61, the cap 62, and the ink absorber 63 constitute an ejection recovery unit 64, and the blade 61 and the ink absorber 63 remove water, dust, and the like from the ink ejection port surface.

Reference numeral 65 is a recording head for recording by the ink jet recording system, which has a structure for ejecting ink by thermal energy as shown in FIGS. 6
Reference numeral 6 denotes a carriage for mounting the recording head 65 and moving the recording head 65. The carriage 66 slidably engages with the guide shaft 67, and a part of the carriage 66 is connected (not shown) to a belt 69 driven by a motor 68. As a result, the carriage 66 moves the guide shaft 6
7, it is possible to move to the recording area by the recording head 65 and its adjacent area.

Reference numeral 51 is a paper feed section for inserting a recording medium, and 52 is a paper feed roller driven by a motor (not shown). With these configurations, the recording medium is supplied to the position facing the ejection port surface of the recording head, and is discharged via the discharge roller 53 as the recording progresses.

In the above structure, when the recording head 65 returns to the home position at the end of recording or the like, the head recovery unit 6
The cap 65 of No. 4 is retracted from the moving path of the recording head, but the blade 61 is projected in the moving path. As a result, the ejection port surface of the recording head 65 is wiped. Further, when the cap 62 comes into contact with the ejection port surface of the recording head 65 to perform capping, the cap 62 moves so as to project into the movement path of the recording head.

When the recording head 65 moves from the home position to the recording start position, the cap 62 and the blade 61 are in the same position as the above-mentioned position during wiping. As a result, the ejection opening surface of the recording head 65 is wiped even during this movement.

The above-described movement of the recording head to the home position is performed not only at the end of recording or at the time of ejection recovery but also at the home adjacent to the recording area at a predetermined interval while the recording head moves in the recording area for recording. The wiper is moved to the position, and the wiping is performed along with the move.

In the case of color recording, a recording head in which cyan, magenta, yellow and black ejection openings are arranged in parallel in one head, or a cyan recording head, a magenta recording head and a yellow recording head are used. And black recording heads can be used in parallel. In this case, each color may be ejected from one ejection port, or two or more droplets of the same color may be simultaneously adhered to the recording medium by ejecting simultaneously from a plurality of ejection ports for each color. Good.

[0048]

The present invention will be described in more detail with reference to the following examples.

Examples 1-3 As raw pulp, 90 parts by weight of LBKP and 10 parts of NBKP
After mixing and beating, 10 parts by weight of kaolin (manufactured by Tsuchiya Kaolin), 0.1 parts by weight of alkenyl succinic anhydride, and 0.2 parts by weight of cationized starch are added, and the basis weight is 72 g by a conventional method. / M ² and a Steckigt sizing degree of 10 seconds were used to make paper.

Next, a coating solution having the composition shown in Table 1 was applied on a base paper using a wire bar so that the dry coating amount was 10 g / m ^2, and then dried at 80 ° C. for 5 minutes to give an undercoat. A coating solution having the composition shown in Table 1 was applied to the undercoat layer at a dry coating amount of 5 g / m ² using a wire bar and heated to 90 ° C while the coating was in a wet state. The surface layer was formed by pressure bonding to the above stainless steel roll and drying to obtain three types of sheet recording media.

[0051]

[Table 1] Comparative Example 1 Example 1 except that the following coating liquid was used instead of the coating liquid.
A sheet-shaped recording medium was obtained in the same manner as in.

[0052]

[Table 2] Comparative Example 2 A sheet-shaped recording medium was obtained in the same manner as in Example 1 except that the surface layer was not provided.

Example 4 On the coating layer side of the sheet-shaped recording media obtained in Examples 1 to 3 and Comparative Examples 1 and 2, ink having the following composition was used to foam the ink by utilizing thermal energy. Color recording was performed under the following conditions with an inkjet recording device that ejected. Table 4 shows the combination of the recording medium and the ink used for recording.

[0054]

[Table 3] *) Dye: Y: C.I. I. Direct Yellow # 86 M: C.I. I. Acid Red # 23 C: C.I. I. Direct Blue # 199 BK: C.I. I. Food Black # 2 Recording conditions: Discharge frequency: 5 kHz Volume of discharged droplets: 40 pl Recording density: 360 DPI Maximum recording density of single color: 8 nl / mm ^{2 The} obtained color print samples were evaluated for the following items. Evaluation Items: (1) Image Density The image densities of solid printing portions of black (BK), cyan (C), magenta (M) and yellow (Y) were measured using a Macbeth densitometer RD-918. (2) Surface glossiness JIS-Z- of the white background of the coating layer surface of the sheet-shaped recording medium
The 75 degree and 20 degree specular glossiness based on 8741 were measured using the digital variable angle gloss meter UGV-5D (made by Suga Test Instruments).

The results of each evaluation are shown in Table 4.

[0056]

[Table 4]

[0057]

INDUSTRIAL APPLICABILITY In the recording medium of the present invention, various properties required for recording with water-based ink, in particular, ink jet recording, are well-balanced and have a good surface glossiness. Since particles are used, recording with higher ink absorbency and higher image density becomes possible.

[Brief description of drawings]

FIG. 1 is a partial vertical cross-sectional view taken along an ink flow path of a head portion of an inkjet recording apparatus that can be used in the method of the present invention.

2 is a cross-sectional view of the head portion shown in FIG. 1 taken along the line AB.

FIG. 3 is a perspective view showing the outer appearance of a multi-head in which a plurality of ink channels are arranged in parallel.

FIG. 4 is a perspective view showing an outline of an inkjet recording apparatus that can be used in the method of the present invention.

[Explanation of symbols]

 13 recording head 14 groove 15 heating head 16 protective film 17-1 and 17-2 electrode 18 heating resistor 19 heat storage layer 20 substrate 21 ink 22 ejection port 24 recording droplet 25 recording medium 26 multi-groove 27 glass plate 28 heating head 51 Paper feed unit 52 Paper feed roller 53 Paper discharge roller 61 Wiping member 62 Cap 63 Ink absorber 64 Ejection recovery unit 65 Recording head 66 Carriage 67 Guide shaft 68 Motor 69 Belt

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenichi Moriya 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yuko Nishioka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Masato Katayama 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (10)

[Claims] 1. A recording medium comprising a base paper mainly composed of fibrous pulp and a filler, and a coating layer containing a pigment, a binder and a cationic substance, wherein the surface of the coating layer is subjected to gloss treatment. A recording medium, wherein the binder is heat-fusion resin particles. 2. The undercoat layer in which the coating layer contains a pigment, a binder composed of heat fusible resin particles, and a cationic substance, and a surface mainly composed of organic resin particles provided on the undercoat layer. The recording medium according to claim 1, comprising a layer. 3. A coating formed by a coating liquid containing a pigment, an aqueous emulsion of heat-sealing resin particles, and a cationic substance in a portion of the coating layer containing a binder composed of heat-fusion resin particles. The recording medium according to claim 1 or 2, which is obtained by heat-drying the layer. 4. The 75 ° specular gloss of the surface of the coating layer is 4
The recording medium according to claim 1, which is 5% or more. 5. The recording medium according to claim 1, wherein the pigment is selected from silica, alumina, hydrated alumina and basic magnesium carbonate. 6. An ink jet recording method, characterized in that an ink droplet is ejected from an ejection port of a recording head according to a recording signal and adhered to the recording medium according to claim 1 to form an image. . 7. The ink droplets are ink droplets containing a recording agent having at least an anionic group.
The inkjet recording method described in 1. 8. A droplet of cyan, magenta, yellow, and black ink is ejected from an ejection port of a recording head in accordance with a recording signal and is attached to the recording medium according to claim 1 to form an image. An ink jet recording method, which comprises forming. 9. The image forming method according to claim 8, wherein a recording head having two or more ejection openings for ejecting ink for each color is used as the recording head, and two or more ink droplets of the same color are ejected at the same time. Inkjet recording method described. 10. The ink jet recording method according to claim 6, wherein the ink is ejected from the recording head by the action of thermal energy.