JPH10217437A - Image recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable attainment of a high image quality being excellent in resolution and graininess by a method wherein at least two coating layers are provided on a substrate, one of these layers contains a specific polymer, and the degree of smoothness of the surface of the coating layer is specified. SOLUTION: It is desirable for a recording medium that a coating layer on a substrate comprises three layers. A polymer expressed by a formula I, a formula II or a formula III is contained in one of these layers. In the formula I, R<1> denotes 1-4C alkyl and x, y and z mole percent ratios of individual components respectively. Marks x', y' and z' and x" and z" in the formulas II and III denote also the percent ratios. A is an ethylenic unsaturated monomer. In the formula II, R denotes 8 or higher C alkyl or phenyl. In the formula III, R<2> denotes a hydrogen atom or the 1-4C alkyl. Besides, the smoothness of the substrate needs to be high so that the Beck degree of smoothness of the surface of the coating layer be made 2000 seconds or above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image recording medium which is excellent in gradation, color reproduction and granularity. Particularly, the present invention relates to a recording medium having excellent photographic quality in ink jet recording and the like.

[0002]

2. Description of the Related Art In recent years, with the spread of personal computers, printers such as ink-jet printers have rapidly become widespread. Further, with the spread of photographic image scanners, photo CDs, and digital cameras, the demand for a printing system for printing digitized photographic images is rapidly increasing. Particularly, the spread of simple and inexpensive inkjet printers is remarkable, and the demand for the image quality of the image is increasing year by year.

[0003] As a recording medium used in the ink jet recording system, a recording sheet provided with an ink receiving layer on a support called a normal paper or an ink jet recording sheet has conventionally been used. However, when these recording sheets are used, they cannot be used in the field of photographic images that require high resolution and gloss, such as bleeding of ink and low gloss.

In order to solve such a problem, a technique of an ink jet recording sheet using gelatin as an ink receiving layer on a resin-coated paper in which both sides of the paper are coated with a resin, that is, a so-called RC (resin coated) paper is used as a support. Kaihei 4-21
No. 6990, and No. 6-64306.

As a method of bringing the appearance and feel of an image output by an ink jet printer closer to those of a conventional photograph,
JP-A-7-179032 discloses a recording medium containing a synthetic hydrophilic resin in an ink receiving layer and an ink jet recording method using the same.

Further, as a method for improving the image quality and stability of the image, JP-A-8-244336 discloses that an ink receiving layer contains gelatin and a basic latex.
A method using a resin-coated support is disclosed.

Certainly, these methods have provided glossy images closer to photographs than conventional ink jet recording paper. However, satisfactory image quality as a photograph in terms of resolution and graininess was not obtained. In particular, when a picture with a relatively small area is printed by a high-speed printer, adjacent inks are mixed and the image quality is reduced, and the image quality is degraded. In addition, when a printer of the type that improves image quality by ejecting a large number of ink droplets having a low density is used, the image quality is deteriorated, and there is a problem that the ink is transferred to another paper or another object on which ink is superimposed. further,
When water droplets adhere, the picture easily bleeds and the color is reduced.

[0008] Resin-coated paper coated with a polymer such as polyolefin has the drawback that it does not absorb ink and that drying after printing is slow. Also, if the surface of the coating layer that absorbs ink has irregularities, the distance between the nozzle of the inkjet printer and the point of attachment of the coating layer is not stable,
The ink is sparsely deposited, and the spread of the ink after the deposition into the coating layer is uneven.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide an image recording medium which is excellent in resolution and granularity and can obtain high image quality. Furthermore, printers that print digital image information such as ink jets, especially ink jet printers that have improved performance and improved printing speed, and ink jet printers that have improved image quality by ejecting a large number of low-density ink droplets, have achieved high image quality. An object of the present invention is to provide a stable recording medium.

[0010]

The above objects of the present invention have been attained by the following means. 1) In a recording medium having at least two coating layers on a support, at least one of the following general formulas (I) and (I)
A recording medium containing at least one polymer represented by (I) or (III), and having a Bekk smoothness of 2,000 seconds or more on the surface of a coating layer. General formula (I)

[0011]

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In the formula, R ¹ represents an alkyl group having 1 to 4 carbon atoms. A represents a repeating unit of a copolymerizable ethylenically unsaturated monomer, x, y, and z each represent a molar percentage ratio of each component, x is 50 to 100, y is 0 to 50, and z is 0 to 30.
Represents Here, x + y + z = 100 is represented. General formula (II)

[0013]

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In the formula, R represents an alkyl group having 8 or more carbon atoms or a phenyl group. R ¹ and A are as defined above. x ',
y 'and z' represent the mole percentage ratio of each component, and x 'is 50
-100, y 'represents 0-50, and z' represents 0-30. Here, x '+ y' + z '= 100. General formula (III)

[0015]

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Where R^TwoIs a hydrogen atom, an atom having 1 to 4 carbon atoms.
Represents a alkyl group, and z is a pyrrolidone ring, an oxazolidone ring
Alternatively, it represents an atom group necessary for forming a lactam ring.
L is a single bond, -CO-, -COO (CH_Two)_n− (N is an integer of 1 to 5
Number), -CONR^Three(CH_Two)_n− (R ^ThreeIs a hydrogen atom or carbon number
1 to 4 alkyl groups, and n is as defined above). A is the same as above
Righteous. x ″ and z ″ represent a mole percentage ratio of each component,
x ″ represents 10 to 100, and z ″ represents 0 to 90. here
x ″ + z ″ = 100. However, in general formula (III)
A shall not contain tertiary and quaternary amino groups. 2) 60 mol% or more of polyvinyl alcohol unit 9
Contains at least one polymer containing 5 mol% or less
The recording medium according to the above 1), wherein: 3) At least one layer has a diameter of 3 μm or more and 30 μm or less.
1) or 2) above, which comprises a soot agent.
A recording medium according to claim 1. 4) At least one layer having a diameter of 10 μm or more and 30 μm or less.
(1) or characterized in that the composition contains a matting agent
The recording medium according to 2). 5) having at least three coating layers
1) The recording medium according to 2) or 3). 6) The above 1), wherein the support is a paper mainly composed of cellulose.
The recording medium according to any one of claims 5 to 5.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The recording medium of the present invention has at least two coating layers on a support.

Preferably, the coating layer comprises at least three layers. The following configurations can be exemplified as preferred embodiments. First layer: an underlayer made of gelatin. This layer contains a white background improving agent such as a fluorescent whitening agent and a hardening agent, and is provided mainly for the purpose of adjusting the swelling behavior and adjusting the curl balance. The film thickness is preferably 0.5 μm or more and 5 μm or less, more preferably 0.7 μm or more and 3 μm or less. Second layer: an image fixing layer containing an ink fixing polymer, a water absorbing polymer, and the like. Thickness is 3μm or more and 20μm
Is preferably 5 μm or more and 15 μm or less. Third layer: a protective layer using gelatin as a binder. This layer contains a matting agent and a surfactant, controls the spread and penetration of ink droplets, and is provided for the purpose of protecting the fixed dye image from physical and chemical disturbances. The film thickness is preferably from 0.2 μm to 2 μm, more preferably from 0.3 μm to 1 μm.

The thickness of the entire coating layer is preferably 5 μm or more and 27 μm or less, more preferably 8 μm or more and 20 μm or less.

The water swelling ratio of the entire coating layer is desirably 100% or more and 300% or less, preferably 150% or more and 2% or less.
More preferably, it is 50% or less. Here, the swelling ratio is a value obtained by dividing the swelling value when water is dropped by the dry film thickness and multiplying by 100. Controlling the swelling behavior is extremely important in controlling ink seepage and spreading, and in preventing scratches and the like in the printer.

Next, the polymer used for the recording medium of the present invention will be described in detail.

The preferred polymer of the present invention will be described in more detail. In the general formula (I), R ¹ is an alkyl group having 1 to 4 carbon atoms (eg, methyl, ethyl, n-butyl, chloromethyl, 2-chloroethyl), and a methyl group is particularly preferred. x, y, z represent the molar percentage ratio of each component, and x is 50 to 100, preferably 60 to 95,
Particularly preferably, it is 65 to 90, y is 0 to 50, preferably 5 to 40, particularly preferably 10 to 35;
Is from 0 to 30, preferably from 0 to 25, particularly preferably from 0 to
20. Here, x + y + z = 100 is represented.

The ethylenically unsaturated monomer represented by A can be appropriately selected from monomers having various structures in consideration of the composition ratio of the copolymer, solubility in a medium, dispersion performance, and the like. Specific examples of the monomer that can be used include the following compounds.

Acrylates: specifically, methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, amyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, 2- Chloroethyl acrylate, 2-acetoxyethyl acrylate, benzyl acrylate, methoxybenzyl acrylate, cyclohexyl acrylate, phenyl acrylate, and the like; Methacrylates: Specific examples thereof include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, and n. -Butyl methacrylate, sec-butyl methacrylate, tert
-Butyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, glycidyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, phenyl methacrylate, cresyl methacrylate, naphthyl methacrylate, 2-hydroxyethyl methacrylate, and the like;

Acrylamides: For example, acrylamide, methylacrylamide, ethylacrylamide, propylacrylamide, butylacrylamide, tert-
Butyl acrylamide, cyclohexyl acrylamide, benzyl acrylamide, phenyl acrylamide, dimethyl acrylamide, diethyl acrylamide, diacetone acrylamide and the like;

Methacrylamides: for example, methacrylamide, methyl methacrylamide, ethyl methacrylamide, butyl methacrylamide, tert-butyl methacrylamide, benzyl methacrylamide and the like;

Olefins: For example, dicyclopentadiene, ethylene, propylene, 1-butene, 1-pentene, isoprene, chloroprene, butadiene, 2,3-
Styrenes: for example, styrene, methylstyrene, dimethylstyrene, ethylstyrene, isopropylstyrene, chloromethylstyrene, methoxystyrene, acetoxystyrene, chlorostyrene, bromostyrene, methyl vinyl benzoate, and the like;

Vinyl ethers: for example, methyl vinyl ether, butyl vinyl ether, hexyl vinyl ether, methoxyethyl vinyl ether and the like;

Dissociating group-containing monomers: acrylic acid, methacrylic acid, itaconic acid, maleic acid, vinylbenzoic acid, crotonic acid, 2-acrylamidopropionic acid, 4-acrylamidobenzoic acid, styrenesulfonic acid, vinylsulfonic acid, acryloyloxyethyl Sulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, or a salt thereof; and others: butyl crotonate, dimethyl itaconate, diethyl fumarate, methyl vinyl ketone acrylonitrile,
Methacrylonitrile and the like;

The compound represented by the general formula (I) of the present invention may be a modified polyvinyl alcohol,
The repeating unit represented by A in the general formula (I) may include a modified polyvinyl alcohol unit. Examples of the repeating unit A obtained by the transformation include the following.

[0031]

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Such a method for modifying polyvinyl alcohol is carried out in various ways using ordinary hydroxyl group modification methods such as cyclic acetalization using an aldehyde, esterification using an acid anhydride, and urethane using an isocyanate. Things are possible.

The compound of the general formula (I) of the present invention is
A general random copolymer may be used, but a block polymer represented by the following general formula (IV) may be used. General formula (IV)

[0034]

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In the formula, R ¹ , A, x, y, and z have the same meanings as described above, and represent x + y + z = 100. D represents an ethylenically unsaturated monomer selected from the same group as A, and may be the same or different from A in the compound. w
Represents a weight percentage ratio to x + y + z, and 1 to 1
000. In addition, w is preferably 3 to 5
00, particularly preferably 10 to 200.
A method for producing this type of block polymer type polyvinyl alcohol and the structure thereof are described in JP-A-59-18911.
No. 3.

In the general formula (II), R represents 8 or more carbon atoms.
Represents an alkyl group or a phenyl group, specifically, C₈H
₁₇−, N-C₁₂H_{twenty five}−, T-C₁₂H_{twenty five}−, C₁₆H₃₃−, C₁₈H₃₇
−, C₃₁H ₆₃−, C₈H₁₇OCOCH_Two−, C₁₂H_{twenty five}OCOCH_Two−, C₁₈H
₃₇OCOCH_Two−, C₁₂H_{twenty five}OCOCH_TwoCH_Two−, C₁₆H₃₃SO_TwoNHCH_TwoCH_Two
−,

[0037]

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And the like. Of these, an unsubstituted alkyl group having 10 or more carbon atoms is particularly preferred. R ¹ has the same meaning as in the above formula (I). x ', y', z 'represent the molar percentage ratio of each component, x' is 50 to 100, preferably 60 to 99.9, particularly preferably 65 to 90, and y 'is 0 to 50, preferably Is from 0.1 to 40, particularly preferably from 5 to 35, and z 'is from 0 to 30, preferably from 0 to 25, particularly preferably from 0 to 20. Where x '
+ Y '+ z' = 100.

In the general formula (III), R ² is a hydrogen atom,
An alkyl group having 1 to 4 carbon atoms (eg, methyl, ethyl, n
-Butyl), and a hydrogen atom and a methyl group are particularly preferred. z represents a group of atoms necessary to form a pyrrolidone ring, an oxazolidone ring, or a lactam ring, and is preferably a pyrrolidone ring or an oxazolidone ring, particularly preferably a pyrrolidone ring. L is a single bond, -CO -, - COO (CH 2) n -
(N is an integer of 1 to 5), -CONR ³ (CH ₂ ) _n- (R ³ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is the same as above), and a single bond or -CO- is particularly preferable. preferable. x ″ and z ″ represent a molar percentage ratio of each component, x ″ is 10 to 100, preferably 20 to 100, particularly preferably 30 to 100, and z ″ is 0 to 90, preferably 0 to 80, Particularly preferably, it is 0 to 70. Here, x ″ + z ″ = 100.

Preferred specific examples of the polymer of the present invention are shown below, but the present invention is not limited thereto.

P-1 poly (vinyl alcohol / vinyl acetate) (molar ratio: 88/12) P-2 poly (vinyl alcohol / vinyl acetate) (molar ratio: 82/18) P-3 poly (vinyl alcohol / vinyl acetate) (Molar ratio 79/21) P-4 Poly (vinyl alcohol / vinyl acetate) (Molar ratio 71/29) P-5 Poly (vinyl alcohol / vinyl acetate) (Molar ratio 65/35)

P-6 poly (vinyl alcohol / vinyl acetate / methacrylic acid) (molar ratio 83/12/5) P-7 poly (vinyl alcohol / vinyl acetate / itaconic acid) (molar ratio 75/20/5) P -8 Poly (vinyl alcohol / vinyl propionate) (molar ratio 80/20) P-9 Poly (vinyl alcohol / vinyl pivalate) (molar ratio 88/12) P-10 Poly (vinyl alcohol / vinyl butyrate) (mol (Ratio 88/12)

[0043]

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P-17 poly (N-vinylpyrrolidone) P-18 poly (N-vinyloxazolidone) P-19 poly (N-vinylpyrrolidone / vinyl alcohol) (70/30 molar ratio) P-20 poly (N- P-21 poly (N-vinylpyrrolidone / vinyl alcohol) (molar ratio 30/70) P-22 poly (N-vinylpyrrolidone / methacrylic acid (molar ratio 50/50) 50)

P-23 poly (N-vinylpyrrolidone / acrylamide / acrylic acid) (molar ratio 70/15/15) P-24 poly (N-vinylpyrrolidone / vinyl acetate / acrylic acid) (molar ratio 50/3 0) / 20) P-25 poly (N-vinyloxazolidone / N-acryloylmorpholine / methacrylic acid) (molar ratio 25/50/25) P-26 poly (N-vinyl-ε-caprolactam / N, N-dimethylacryl) Amide) (40/60 molar ratio)

[0046]

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[0047]

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The molecular weight of the polymer of the present invention is not particularly limited, and the suitable range of the molecular weight may vary depending on the structure of the polymer.
10,000, particularly preferably between 3000 and 300,000.

The polymer of the present invention can be obtained by carrying out polymerization using polymerization techniques such as solution polymerization, suspension polymerization, emulsion polymerization, and precipitation polymerization, which are well-known. Polymer, Vol. 1, pp. 246-290, Vol. 3, pp. 1-108, and the like.
The polymer having a polyvinyl alcohol unit in the molecule may be obtained by previously conducting homo- or copolymerization of vinyl esters by the above-mentioned method, and then producing the vinyl alcohol unit by hydrolysis. Further, the compound of the general formula (II) can be synthesized by coexisting a mercaptan compound represented by R-SH at the time of polymerization and hydrolyzing the obtained polymer.

The polymer used in the recording material of the present invention has a polyvinyl alcohol unit content of 60 mol% or more and 95 mol% or more.
It is preferably at most mol%. More preferably, the content of the polyvinyl alcohol unit is 70 mol% or more and 90 mol% or less, and 75 mol% or more and 85 mol%.
It is most preferred that: If the content of the polyvinyl alcohol unit is high, the unevenness of the image becomes large, and the graininess is deteriorated. In addition, the density of the image decreases. Conversely, when the content of the polyvinyl alcohol unit is low, the coatability is deteriorated and the uniformity of the surface of the recording medium is impaired.

The recording medium of the present invention has a diameter of 3 μm
It is desirable to contain a matting agent having a size of not less than 30 μm. More preferably, the particle size of the matting agent is from 10 μm to 30 μm.

As the matting agent added to the recording material of the present invention, conventionally known matting agents can be used. Matting agents are well known in the photographic art and can be defined as discrete solid particles of an inorganic or organic material dispersible in a hydrophilic organic colloid binder. Examples of inorganic matting agents include oxides (eg, silicon dioxide, titanium oxide, magnesium oxide, aluminum oxide, etc.) and alkaline earth metal salts (eg, sulfates and carbonates, specifically, barium sulfate, carbonate Calcium, magnesium sulfate, calcium carbonate) and glass. In addition, West German Patent 2,5
29,321; British Patent No. 760,775;
260,772, U.S. Patent No. 1,201,905,
2,192,241, 3,053,662, 3,062,649, 3,257,206, 3,322,555, 3,353,958, and 3 No. 3,370,951, No. 3,411,907, No. 3,437,484, No. 3,523,022, No. 3,615,554, No. 3,635,714, No. 3,769 020, 4,021,245, 4,029,504, etc. can also be used.

Examples of the organic matting agent include starch, cellulose ester (eg, cellulose acetate propionate, etc.), cellulose ether (eg, ethyl cellulose, etc.), and synthetic resin. Examples of synthetic resins are water-insoluble or poorly soluble synthetic polymers, such as alkyl (meth) acrylate, alkoxyalkyl (meth) acrylate, glycysilyl (meth) acrylate, (meth) acrylamide, vinyl ester (eg, vinyl acetate), Acrylonitrile, olefins (eg, ethylene, etc.), styrene, benzoguanamine, formaldehyde condensate, etc., alone or in combination, or acrylic acid, methacrylic acid, α, β-unsaturated dicarboxylic acid, hydroxyalkyl (meth) acrylate, sulfoalkyl ( A polymer having a combination of meth) acrylate, styrene sulfonic acid and the like as a monomer component can be used. In addition, epoxy resin, nylon, polycarbonate, phenol resin, polyvinyl carbazole, polyvinylidene chloride, and the like can also be used. In addition, British Patent No. 1,055,713 and U.S. Pat.
9,213, 2,221,873, 2,26
8,662, 2,322,037, 2,37
No. 6,005, No. 2,391,181, No. 2,70
Nos. 1,245, 2,992,101, 3,07
9,257, 3,262,782, 3,44
3,946, 3,516,832, 3,53
9,344, 3,591,379, 3,75
Nos. 4,924, 3,767,448 and JP-A-49-49.
Organic matting agents described in 106821, 57-14835 and the like can be used.

Among them, polymethyl methacrylate, benzoguanamine / formaldehyde condensed polymer (benzoguanamine resin, specifically represented by the following formula, for example, trade name Eposter; Nippon Shokubai Chemical Co., Ltd .: existing chemical substances 7-31, etc. ), Polyolefins (for example, flow beads LE-1080, CL-2080, H
E-5023; manufactured by Iron and Steel Chemical Co. or trade name Chemipearl V
-100; manufactured by Mitsui Petrochemical)

[0055]

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Polystyrene beads (manufactured by Moritex), nylon beads (manufactured by Moritex), AS resin beads (manufactured by Moritex), epoxy resin beads (manufactured by Moritex), polycarbonate resins (manufactured by Moritex), and the like are preferable. As alkali-soluble matting agents, JP-A-53-7231, JP-A-58-66937, and JP-A-58-66937.
No. 0-8894, an alkali-soluble matting agent such as an alkyl methacrylate / methacrylic acid copolymer,
An alkali-soluble polymer having an anionic group described in 8-166341 can also be used. These matting agents may be used in combination. (See, for example, JP-A-58-145)
No. 935, two or more kinds of fine particle powders having different Mohs' hardness are used in combination, and two or more kinds of spherical matting agents having different average particle diameters described in JP-A No. 59-149356 are used in combination. Such as the use of an irregular matting agent and a spherical matting agent such as polymethyl methacrylate in the back layer. )

The coating layer of the present invention has a coating aid, antistatic,
Various surfactants may be included for various purposes such as improving slipperiness, emulsifying and dispersing, and preventing adhesion. For example, saponins (steroids), alkylene oxide derivatives (eg, polyethylene glycol, polyethylene glycol / polypropylene glycol condensate, polyethylene glycol alkyl ethers or polyethylene glycol alkyl aryl ethers, polyethylene glycol esters, polyethylene glycol sorbitan esters,
Polyalkylene glycol alkylamines or amides, silicone polyethylene oxide adducts),
Nonionic surfactants such as glycidol derivatives (eg, alkenyl succinic acid polyglyceride, alkylphenol polyglyceride), fatty acid esters of polyhydric alcohols, and other alkyl esters; alkyl carboxylate, alkyl sulfonate, alkyl benzene sulfonate Salts, alkyl naphthalene sulfonates, alkyl sulfates, alkyl phosphates, N-acyl-N-alkyl taurates, sulfosuccinates, esphoalkyl polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl eico Carboxy group, sulfo group, such as sanates, etc.
Anionic surfactants containing acidic groups such as phospho, sulfate and phosphate groups; amphoteric interfaces such as amino acids, aminoalkyl sulfonic acids, aminoalkyl sulfate or phosphate esters, alkyl betaines, amine oxides Activators; cationic surfactants such as alkylamine salts, aliphatic or aromatic quaternary ammonium salts, heterocyclic quaternary ammonium salts such as pyridinium and imidazolium, and phosphonium or sulfonium salts containing aliphatic or heterocyclic rings. Can be used.

A sliding agent may be added to the recording material of the present invention. Examples of the slipping agent include higher alkyl sodium sulfate, higher fatty acid higher alcohol ester, carbowax, higher alkyl phosphate ester, and silicon compounds. In particular, the compounds described in U.S. Pat. Nos. 2,882,157, 3,121,060, 3,850,640 and JP-A-51-141623 may be used alone or in combination of two or more. It is particularly effective. Also, French Patent No. 2,180,465 and British Patent No. 955,061
Nos. 1,143,118 and 1,270,578
Nos. 1,320,564 and 1,320,757
And JP-A-49-5017 and JP-A-51-141623.
No. 54-159221, No. 56-81841,
Research Disclosure
No. 13969, British Patent Nos. 1,263,722, 2,588,765, 2,739,891, 3,018,178, 3,042,522, 3,080, Nos. 317, 3,082,087, 3,121,060, 3,222,178, 3,295,979, 3,489,567 and 3,516,832 And 3,658,573, 3,679,411, and 3,870,521. The application amount of the sliding agent is
About 5-200 mg / m ² is suitable.

The constituent layers (including the back layer) of the recording medium of the present invention may contain silica, particularly colloidal silica, for the purpose of improving adhesion resistance, improving film strength, and improving curl balance. . Colloidal silica has an average particle size of 7
The main component is silicon dioxide in the range of mμ to 120 μm, and may contain alumina or sodium aluminate as a minor component. These colloidal silicas may contain, as a stabilizer, an inorganic base such as sodium hydroxide, potassium hydroxide, lithium hydroxide or ammonium hydroxide, or an organic salt such as tetramethylammonium ion. In particular, as a stabilizer for colloidal silica, colloidal silica comprising potassium hydroxide or ammonium hydroxide is preferable. These colloidal silicas are described, for example, in Egon Mategevick
ijevic) ed., Surface and Colloid Science, Volume 6, 3-100
(1973, John Wiley & Sons). Specific examples of colloidal silica include DuPont (EI
do pont de Nemours & Co, (USA)) from Ludox AM, Ludo
x AS, Ludox LS, Ludox TM, Ludox HS, etc. from Nissan Chemical Co., Ltd. (Tokyo, Japan) Snowtex 20,
Under the trade names of Snowtex C, Snowtex N, Snowtex O, etc., Monsanto Co, (USA) has issued Syton C-
30, Syton 200, etc., as well as Nalco Chem, CO
(USA) from Nalcoag 1030, Nalcoag 1060, Na
Examples include those marketed under the trade name such as lcoag ID-21-64. The preferred use amount of the colloidal silica is 0.05 to 1.0 in terms of a dry weight ratio to gelatin used as a binder, particularly preferably 0.2 to 1.0.
0.7.

In the present invention, it is preferable to use an antibacterial and antibacterial agent for the image receiving material in order to prevent decay of the dispersion or coating solution of various chemicals. The antibacterial and antibacterial agent used in the present invention may be any water-soluble one,
Specifically, thiazolyl benzimidazole compounds, isothiazolone compounds, chlorophenol compounds, bromophenol compounds, thiocyanic acid and isothianoic acid compounds, acid azide compounds, diazine and triazine compounds, thiourea compounds, Alkylguanidine compounds, quaternary ammonium salts, organotin and organozinc compounds,
Cyclohexylphenol compounds, imidazole and benzimidazole compounds, sulfamide compounds,
There are various antibacterial agents and fungicides such as active halogen compounds such as chlorinated isocyanuric acid and sodium, chelating agents, sulfite compounds, and antibiotics represented by penicillin. Also other LE West (LEWest), water
Quality Criteria ("Water Quality Criteria")
Fungicides described in Phot. Sci. And Eng., Vol 9, No. 6 (1965); JP-A-57-8542 and JP-A-58-1051.
No. 45, No. 59-126, 533, No. 55-111,
No. 942 and No. 57-157244; various antifungal agents; antibacterial and antifungal agents described by Hiroshi Horiguchi in "The Chemistry of Antifungal and Fungicide" (published by Sankyo Publishing Co., Ltd. in 1982).

In the present invention, for fixing the dye,
Polymer mordants and dye-receptive polymers described in JP-A-57-198458 can be used. The coating layer for fixing the dye may be provided not only on one side of the support but also on both sides. In the present invention, the dye-accepting polymer that can be used for the coating layer is made of a heat-resistant organic polymer having a glass transition temperature of 40 ° C. or more and 250 ° C. or less. In the present invention, the mechanism by which the dye released from the dye-providing substance enters the polymer has not been clarified in many respects. It is generally believed that at processing temperatures above the glass transition temperature, the thermal motion of the polymer chains increases and the resulting dye can penetrate into the interchain molecular gaps.

The following are examples of the organic high molecular substance used in the present invention. To list them, molecular weight 2
000 to 85000 polystyrene, a polystyrene derivative having a substituent having 4 or less carbon atoms, polyvinylcyclohexane, polydivinylbenzene, polyvinylcarbazole,
Polyacetals such as polyallyl benzene, polyvinyl polymer and polyvinyl butyral, polyvinyl chloride, chlorinated polyethylene, polytrichlorofluoroethylene,
Polyacrylonitrile, poly-N, N-dimethylacrylamide, polyacrylate having p-cyanophenyl group, pentachlorophenyl group and 2,4-dichlorophenyl group, polyacrylchloroacrylate, polymethylmethacrylate, polyethylmethacrylate, polypropylmethacrylate, Polyisopropyl methacrylate, polyisobutyl methacrylate, poly-tertiary
Polyesters such as butyl methacrylate, polycyclohexyl methacrylate, polyethylene glycol dimethacrylate, poly-2-cyano-ethyl methacrylate, polyethylene terephthalate, polysulfone, bisphenol A polycarbonate, polycarbonates, polyanhydride, polyamides and cellulose acetates. . Also, polymer handbook 2nd edition J. Brandrup, EHImmergut, edited by John Wil
Glass transition temperature 40 ° C described by ey & Sons
As described above, synthetic polymers having a temperature of 250 ° C. or less are also useful. Even if these polymer substances are used alone or in combination,
Moreover, you may use it as a copolymer combining several or more.

The mordant can be arbitrarily selected from commonly used mordants, and among them, a polymer mordant is particularly preferable. Here, the polymer mordant includes a polymer containing a tertiary amino group, a polymer having a nitrogen-containing heterocyclic moiety, and a polymer containing these quaternary cationic groups. Preferred specific examples of homopolymers and copolymers containing a vinyl monomer unit having a tertiary amino group include the following. The number of the monomer unit represents mol% (the same applies hereinafter).

[0064]

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And so on. Specific examples of homopolymers and copolymers containing a vinyl monomer unit having a tertiary imidazole group include U.S. Pat.
Mordants described in JP-A-115,124, JP-A-3,148,061, JP-A-60-118834, JP-A-60-122941, JP-A-62-244043, JP-A-62-244036 and the like. And the following.

[0066]

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[0067]

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And so on. Preferred specific examples of homopolymers and copolymers containing a vinyl monomer unit having a quaternary imidazolium salt include British Patent No. 2,056,101.
No. 2,093,041, No. 1,594,96
No. 1, U.S. Pat. Nos. 4,124,386 and 4,11
No. 5,124, No. 4,273,853, No. 4,4
No. 50,224 and JP-A-48-28325, including the following mordants.

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And so on. Other preferred examples of homopolymers and copolymers containing a vinyl monomer unit having a quaternary ammonium salt include US Pat. No. 3,709,6.
No. 90, No. 3,898,088, No. 3,958,
No. 995, JP-A-60-57836 and JP-A-60-606.
No. 43, No. 60-122940, No. 60-12294
No. 2, 60-235134, and the like, including the mordants described below.

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And so on. Other US Pat. No. 2,548,5
No. 64, No. 2,484,430, No. 3,148,
161 and 3,756,814; vinylpyridine polymer and vinylpyridinium cationic polymer; US Pat. No. 3,625,69
No. 4, No. 3,859,096, No. 4,128,5
No. 38, British Patent No. 1,277,453, etc .; a polymer mordant capable of crosslinking with gelatin and the like;
U.S. Pat. Nos. 3,958,995 and 2,721,8
No. 52, 2,798,063, JP-A-54-11
No. 5228, No. 54-145529, No. 54-260
No. 27, etc .; an aqueous sol type mordant disclosed in U.S. Pat. No. 3,898,088; a water insoluble mordant disclosed in U.S. Pat. No. 3,898,088; U.S. Pat. No. 137333) Reactive mordants capable of forming a covalent bond with the dyes disclosed in the specification and the like; further, U.S. Pat. Nos. 3,709,690 and 3,788,855.
No. 3,642,482, No. 3,488,70
No. 6, No. 3,557,066, No. 3,271, 1
No. 47, No. 3,271,148, JP-A-50-71
No. 332, No. 53-30328, No. 52-15552
No. 8, No. 53-125, and No. 53-1024. In addition, U.S. Pat. Nos. 2,675,316 and 2,882,15
The mordant described in the specification of No. 6 can also be mentioned. The molecular weight of the polymer mordant of the present invention is suitably from 1,000 to 1,000,000, and particularly preferably from 10,000 to 200,000. The above-mentioned polymer mordant is usually used by being mixed with a hydrophilic colloid. As the hydrophilic colloid, a hydrophilic colloid, a superabsorbent polymer described below, or both of them can be used, and gelatin is most typical. The mixing ratio between the polymer mordant and the hydrophilic colloid, and the amount of the polymer mordant applied, are easily determined by those skilled in the art according to the amount of the dye to be morded, the type and composition of the polymer mordant, and the image forming process used. The mordant / hydrophilic colloid ratio is 20/80 to 80/20 (weight ratio), and the mordant application amount is suitably 0.2 to 15 g / m ² , preferably 0.5 to 8 g / m ^2. preferably used in m ^2. The dye-fixing layer constituting the coating layer may be composed of one layer or may be composed of two or more layers. Further, an auxiliary layer other than the dye-fixing layer may be provided above or below the dye-fixing layer. In particular, it is preferable to provide a protective layer on the dye fixing layer having a mordant to improve the strength of the image for mechanical operation.

The hardener used in the recording medium of the present invention is not particularly limited, and known hardeners such as aldehydes (formaldehyde, glyoxal, glutaraldehyde, etc.) and aziridines (eg, PB Report 1)
9,921, U.S. Pat. Nos. 2,950,197, 2,964,404, 2,983,611 and 3,271,175, JP-B-46-40.
No. 898, those described in JP-A-50-91315), isoxazoles (for example, US Pat.
1,609), epoxy type (for example, U.S. Pat. No. 3,047,394, West German Patent 1,0).
No. 35,663, British Patent No. 1,033,518, JP-B-48-35495, vinyl sulfones (for example, 1,3,5-triacryloyl-hexahydro-s) -Triazine, bis (vinylsulfonyl) methyl ether, N, N'-ethylene-bis (vinylsulfonylacetamide) ethane,
N, N'-trimethylene-bis (vinylsulfonylacetamide) and the like, for example, PB Report 19,92
0, West German Patent Nos. 1,100,942 and 2,337,
412, 2,545,722, 2,635,5
No. 18, No. 2,742,308, No. 2,749,26
0, UK Patent No. 1,251,091, Japanese Patent Application No. 45-
No. 54236, No. 48-110996, U.S. Pat. Nos. 3,539,644 and 3,490,911), acryloyl-based (for example, Japanese Patent Application No. 48-27949, U.S. Pat. No. 3,640,720
And carbodiimide-based compounds (for example, U.S. Pat. Nos. 2,938,892 and 4,043).
Nos. 818, 4,061,499, JP-B-46-38715 and JP-A-49-15095, and triazines (for example, 2,4-
Dichloro-6-hydroxy-s-triazine and the like, and also, for example, West German Patent Nos. 2,410,973 and 2,55.
3,915, U.S. Pat. No. 3,325,287, and those described in JP-A-52-12722),
N-methylols (dimethylol urea, methylol dimethylhydantoin, etc.), dioxane derivatives (2,3-
Dihydroxydioxane), mucohalic acid (mucochloric acid, mucophenoxycyclolic acid, etc.), dialdehyde starch, 1-chloro-6-hydroxytriazinylated gelatin, maleimide type, acetylene type, methanesulfonic acid ester type hard Membrane agents can be used. As the polymer hardener, for example, US Pat. No. 3,396,
No. 029, polymers having an aldehyde group (for example, copolymers of acrolein, etc.);
No. 27, a polymer having a dichlorotriazine group described in Research Disclosure 17333 (1978), a polymer having an epoxy group described in U.S. Pat. No. 3,623,878, Research Disclosure 16725 (1978), U.S.A. Patent No. 4,16
No. 1,407, JP-A-54-65033, JP-A-56-1
For example, a polymer having an active vinyl group or a group which can be a precursor thereof described in Japanese Patent No. 42524 or a polymer having an active ester group described in JP-A-56-66841 can be used. The addition amount of the hardener is optional, but is usually about 0.1 to 30% by weight, especially 0.5 to 30% by weight of the one which can react with the hardener in the hydrophilic colloid which is a binder.
10 wt% is appropriate.

As the binder for the coating layer, a hydrophilic binder is preferably used. Examples thereof include the above-mentioned Research Disclosure and JP-A-64-13546.
And those described on pages (71) to (75). Specifically, a transparent or translucent hydrophilic binder is preferable. For example, proteins such as gelatin and gelatin derivatives, other animal proteins (eg, egg white, egg yolk, casein, whey protein, etc.) or cellulose derivatives, starch, Arabic Examples include natural compounds such as polysaccharides such as rubber, dextran and pullulan, and synthetic high molecular compounds such as polyvinyl alcohol, polyvinylpyrrolidone, and acrylamide polymer. In particular, polyvinyl alcohol or a copolymer of vinyl alcohol and a vinyl monomer having a carboxylic acid group and those whose terminals are alkyl-modified are preferably used for the purpose of improving the stability of dispersions such as emulsions and latexes. Also, vinyl having U.S. Patent No. 4,960,681, superabsorbent polymers described in JP-A-62-245,260, etc., i.e. -COOM or -SO ₃ M a (M is a hydrogen atom or an alkali metal) A homopolymer of a monomer or a copolymer of the vinyl monomers or another vinyl monomer (for example, sodium methacrylate, ammonium methacrylate, Sumikagel L-5H manufactured by Sumitomo Chemical Co., Ltd.) is also used. These binders can be used in combination of two or more kinds. Particularly, a combination of gelatin and the above binder is preferable. The gelatin may be selected from lime-processed gelatin, acid-processed gelatin, and so-called demineralized gelatin having a reduced content of calcium and the like according to various purposes, and it is also preferable to use them in combination.

In the coating layer, a high boiling organic solvent can be used as a plasticizer, a slipping agent, an anti-curl agent or an agent for improving the releasability of the light-sensitive material and the dye fixing element. Specifically, the above-mentioned Research Disclosure and
245, 253 and the like. Furthermore,
For the above purpose, various silicone oils (all silicone oils from dimethyl silicone oil to modified silicone oil in which various organic groups are introduced into dimethyl siloxane) can be used. Examples thereof include various modified silicone oils described in “Modified Silicone Oil” Technical Documents P6 to 18B issued by Shin-Etsu Silicone Co., Ltd., particularly carboxy-modified silicone (trade name: X-22-371).
0) is effective. Also, JP-A-62-21595.
No. 3, 63-46,449 are also effective.

The coating layer may contain an anti-fading agent. Anti-fading agents include, for example, antioxidants, ultraviolet absorbers, or certain metal complexes. As antioxidants, for example, chroman compounds, coumaran compounds,
There are phenol compounds (for example, hindered phenols), hydroquinone derivatives, hindered amine derivatives, and spiroindane compounds. Also, Japanese Unexamined Patent Publication No.
The compounds described in -159,644 are also effective. Examples of ultraviolet absorbers include benzotriazole-based compounds (such as U.S. Pat. No. 3,533,794), 4-thiazolidone-based compounds (such as U.S. Pat. No. 3,352,681), and benzophenone-based compounds (Japanese Unexamined Patent Publication No. Sho 46-2). , 784, etc.) and JP-A-54-48,535 and 62-136, 64.
No. 1, 61-88, 256 and the like. Further, ultraviolet absorbing polymers described in JP-A-62-260152 are also effective. Examples of the metal complex include U.S. Pat. Nos. 4,241,155, 4,245,018, columns 3 to 36, and 4,254,195, columns 3 to 8,
JP-A Nos. 62-174, 741, 61-88, 256
Nos. 27-29, 63-199,248,
-75,568 and 1-74,272.

The recording medium of the present invention comprises the above-mentioned coating layer provided on a support, and has a coating layer surface having a Beck smoothness of 2000 seconds or more. In order to increase the Beck smoothness to 2000 seconds or more, the support must have high smoothness. Here, the Beck smoothness is an index indicating the smoothness of the paper surface, and 10 ml of air is blown under a specified pressure difference between the paper surface and the glass standard surface polished on the optical surface. It is represented by the time (number of seconds) required to pass.

The surface smoothness of the coating layer of the present invention is preferably at least 2000 seconds in Beck's smoothness.
In less than seconds, the phenomenon that the ink is diffused to the periphery due to the rough surface and each dot shape is blurred, and that each dot shape itself does not become a predetermined shape due to the rough surface, and a part of the dot shape or A phenomenon in which the resolution is reduced due to lack of all occurs. Both the blurring phenomenon and the phenomenon that the resolving power is reduced are resolved as the numerical value (seconds) of the Beck smoothness increases. For example, Beck smoothness is 26
When the time is longer than 00 seconds, the dots are faithfully reproduced in the original image, and the white spots in the image due to the dropout of the dots are reduced. As for blur, the Beck smoothness is 2000
Although there is no substantial hindrance at more than 2 seconds, when viewed in an enlarged manner, there is some stain around the dots from the halftone to the highlight due to the diffusion of the dye, but no stain occurs after 2600 seconds.

Examples of the support having high smoothness include synthetic paper (polyolefin-based, polystyrene-based), high-quality paper, art paper, coated paper, cast-coated paper, wallpaper-backing paper,
Cellulose fiber paper such as synthetic resin impregnated paper, emulsion impregnated paper, or synthetic rubber latex impregnated paper, synthetic resin internal paper, paperboard, etc., and various plastics such as polyolefin, polyvinyl chloride, polyethylene terephthalate, polystyrene, methacrylate, and polycarbonate. Films or sheets can be used. Also, a laminate of the combination of the following can be used, and examples thereof include cellulose fiber paper and synthetic paper, cellulose fiber paper and plastic film or sheet, and synthetic paper to cellulose fiber paper to synthetic paper.

As the synthetic paper of (1), especially a synthetic paper provided with a paper-like layer having fine pores (for example, Oji Oil Chemical Synthetic Paper Co., Ltd.)
Manufactured by YUPO Co., Ltd., or a sheet directly provided with a paper-like layer containing fine pores can also be used. Any of the above supports can be used, but it is preferable to use cellulose-based paper such as art paper, coated paper, cast coated paper or photographic baryta paper as the support.

The art paper preferably used in the present invention is a paper obtained by mixing a mineral pigment and a natural or synthetic adhesive, applying the mixture mechanically to base paper, drying it, and giving it a high gloss with a super calender or the like. It is. Some are coated on both sides, some are coated on one side, and others are matte. The coated paper is a paper coated with a pigment in a dry portion of the paper machine or a pigment coated by a coater separated from the paper machine. The coating amount is lower than that of art paper, and the smoothness is lower. Cast coated paper is a high gloss paper made to enhance the printing effect more than art paper.While the plastic coating material was soft, it was pressed against a hard mirror-like surface and dried to give a high gloss. It has high whiteness. It also has folding resistance.

As the baryta paper, a base paper made of high quality wood fiber or pulp is used. The base paper is usually coated with a baryta. The baryta liquid is a dispersion of fine crystals of barium sulfate in a gelatin liquid.The baryta layer has the effect of increasing the reflectivity of the paper surface, increasing whiteness, increasing gloss, and increasing the sharpness of prints and the depth of black. There is. The base paper coated with the baryta layer is called baryta paper. The thickness of the baryta layer is 10-25 μm,
It is applied about 40g to 1m ^2. Especially high gloss, 6
It may be applied up to about 0 g. As for the size of barium sulfate crystals, fine ones having a diameter of 0.5 μm or less are used for glossy paper, while semi-glossy papers are slightly large, and non-glossy papers are about 3 μm in size.

The recording material of the present invention can be used in all systems including dye release and reception, including ink jet printing, sublimation type thermal transfer printing, and dye diffusion transfer printing. Among them, when used for inkjet printing, the effects of the present invention are greatly exhibited.

There is no particular limitation on the type of ink jet printing, and the recording medium of the present invention can be used regardless of whether it is a continuous type or an on-demand type. The type of the inkjet head is not limited, and is preferably used for all printers including a piezo type, a bubble jet type, a thermal jet type, and a type using ultrasonic waves.

The recent advances in ink-jet systems have been remarkable, for example, a method of ejecting a large number of thin inks called photo inks in a small volume, and improving the image quality by using a plurality of inks having substantially the same hue and different densities. Many new methods have been proposed and put into practical use, such as a method using a colorless and transparent ink. The recording material of the present invention is preferably used in any of these systems, but the effect of improving the image quality is remarkably exhibited particularly in a printer having a high printing speed or a printer in which a large amount of low density ink is ejected.

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The present invention will be described below with reference to examples. Example 1 A cast coated paper (Espricoat C manufactured by Sanyo Kokusaku Pulp) having a basis weight of 157 g / m ² was used as a support, and the following coating layer was applied thereon to prepare a sample. The main purpose of addition of each compound is shown in parentheses, but the purpose of addition is not limited thereto.

First layer: alkali-treated gelatin 1.0 g / m ² Compound UV-01 (fluorescent brightener) 0.03 g / m ² Compound H-02 (hardener) 0.08 g / m ² _{Na 2 B 2 O 4 · 4H} 2 O ( thickener) 0.10 g / m ² compound W-04 (surfactant) 0.02 g / m ² compound F-08 (spoilage inhibitor) 0.001 g / M ²

Second layer: Compound B-05 (fixation of dye) 5.0 g / m ² Compound P-2 (fixation of dye and improvement of image quality) 3.5 g / m ² Compound W-04 (surfactant) ) 0.06 g / m ²

Third layer: alkali-treated gelatin 0.3 g / m ² compound M-06 (matting agent) 0.18 g / m ² compound W-04 (surfactant) 0.02 g / m ² compound W -07 (surfactant) 0.02 g / m ² Compound F-08 (rotproofing agent) 0.002 g / m ²

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The Beck smoothness of the surface of the coating layer of the obtained sample was about 5000 seconds. Using the sample cut to A4 size, a photographic image was printed on the sample using an inkjet color printer BJC-420J manufactured by Canon Inc. As the photographic image, various photographs taken by a camera EOS-10 manufactured by Canon Inc. using a color reversal film Provia 100 manufactured by Fuji Photo Film Co., Ltd. were read by a scanner and digital signals were used. 20 kinds of pictures, such as landscape, nature, person, fashion, and still life, were selected based on the distribution of subjects of ordinary photograph users.

The surface of the printed sample does not feel wet when touched with a finger. Also, there was little ink bleeding and no image unevenness. Example 2 A basis weight of 17 was used in place of the support cast coated paper of Example 1.
4 g / m ² art paper (SK super art paper; manufactured by Sanyo Kokusaku pulp), synthetic paper (FPG250; manufactured by Oji Yuka synthetic paper), 180 μm thick baryta paper (manufactured by Fuji Photo Film), and basis weight of 150 g / m ² Coating paper (manufactured by Kanzaki Paper Co., Ltd.) was used as a support, and the same coating layer as in Example 1 was applied to prepare four types of samples. The Beck smoothness of each of the obtained samples was 2000 seconds or more. Printing was performed using an inkjet printer in the same manner as in Example 1. The surface of the printed sample does not feel wet when touched with a finger. In the case where the synthetic paper was used for the support, the ink bleeding was slightly recognized, but in the other samples, the ink bleeding was small.

Claims (4)

[Claims] (1) a support having at least two coating layers on a support;
Recording medium, at least one of the following general formula
Less polymer represented by (I), (II) or (III)
And the coating layer has a Beck smoothness of 2
2,000 seconds or more. General formula (I)Where R¹Represents an alkyl group having 1 to 4 carbon atoms. A is
Shows the repeating units of the polymerizable ethylenically unsaturated monomer.
X, y, z represent the molar percentage ratio of each component, and x is 5
0 to 100, y represents 0 to 50, and z represents 0 to 30. here
Represents x + y + z = 100. General formula (II)In the formula, R represents an alkyl group having 8 or more carbon atoms or a phenyl group.
You. R¹, A are as defined above. x ', y', z 'are
X 'represents 50 to 100;
y 'represents 0 to 50, and z' represents 0 to 30. Where x '+
It represents y '+ z' = 100. General formula (III)Where R^TwoRepresents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.
And z is a pyrrolidone ring, an oxazolidone ring or a lactam
Represents the group of atoms necessary to form a ring. L is a single bond,
-CO-, -COO (CH_Two)_n-(N is an integer of 1 to 5), -CONR
^Three(CH_Two)_n− (R ^ThreeIs a hydrogen atom or an alkyl having 1 to 4 carbon atoms
A kill group, and n is the same as defined above). A has the same meaning as described above.
x ″ and z ″ represent a mole percentage ratio of each component, and x ″ is 10
１００100 and z ″ represent 0 to 90. Here, x ″ + z ″ =
100 is represented. However, in the general formula (III), A is a third class
And quaternary amino groups. 2. The recording medium according to claim 1, wherein the recording medium contains at least one polymer containing a polyvinyl alcohol unit at a ratio of 60 mol% or more and 95 mol% or less. 3. The recording medium according to claim 1, having at least three coating layers. 4. The recording medium according to claim 1, wherein the support is a paper mainly composed of cellulose.