JPH11348408A - Picture recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet picture recording medium, having luster and smoothness approximated to a photo print, improved in the reproduction of color and capable of reproducing natural and bright skin color. SOLUTION: An ink jet recording medium, provided with an ink receptor layer on at least one side of a substrate, is constituted of the substrate of a resin coated paper, consisting of a sheet of paper whose both sides are coated by a resin and whose whiteness of the part, not printed yet, is specified so as to have the values within the ranges of 91<=L*<=98, -0.5<=a*<=+1.0, -4.5<=b*<=-2.5, which are specified by CIE1976.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink-jet image recording medium having gloss and smoothness close to those of a photographic print, and excellent in color reproduction, especially in skin color reproduction. Further, the present invention relates to an ink jet image recording medium having excellent image storability.

[0002]

2. Description of the Related Art In recent years, with the spread of personal computers, ink jet printers have rapidly become widespread. The demand for print quality and storage stability 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.

With the use of such resin-coated paper, prints having gloss and smoothness close to those of conventional photographs can be obtained, and the importance of storage stability of prints is increasing. It is common practice to add a mordant polymer to the ink receiving layer as a means of improving the fading of the printed ink dye and preventing the dye from bleeding. Particularly, a polymer compound containing a vinylpyrrolidone component is effective in improving the fading of a printed image.
Conventionally, there is a lot of public information on a polymer compound containing a vinylpyrrolidone component.
No. 3111 discloses an inkjet recording sheet containing a polyvinylpyrrolidone copolymer crosslinked by a covalent bond.

However, when a polymer containing a vinylpyrrolidone component is used as a mordant, there is a problem that the whiteness of the unprinted portion is reduced, the hue shifts to bluish, and the skin color becomes cold. Further, depending on the state of the light source at the time of photographing, there is a problem that the reproduction of the skin color of the dark part and the light part of the skin is shifted, giving an unnatural impression.

Accordingly, the present inventors have conducted intensive studies and as a result,
It has been found that by adjusting the white background to a certain hue and brightness, the unnatural impression described above, particularly the connection between the light and dark parts of the flesh color, is improved, and natural reproduction can be achieved.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide an ink jet image recording medium which has gloss and smoothness close to those of a photographic print, has improved color reproduction, and can reproduce natural light flesh color. . Another object of the present invention is to provide an ink jet image recording medium having excellent image storability.

[0009]

The above object of the present invention has been attained by the following. 1) In an ink jet recording medium provided with an ink receiving layer on at least one surface of a support, the support is a resin-coated paper in which both sides of the paper are coated with a resin, and the whiteness of an unprinted portion is defined by CIE1976. An ink jet recording medium, wherein L *, a *, and b * are in the following ranges. 91 ≦ L * ≦ 98−0.5 ≦ a * ≦ + 1.0−4.5 ≦ b * ≦ −2.5 2) Addition of a fluorescent whitening agent and a colored dye, described in 1) above. Image recording medium. 3) The image recording medium according to 1) or 2), which contains at least one compound represented by the following general formula (E) as a fluorescent whitening agent.

[0010]

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(4) The image recording medium according to any one of (1) to (3), wherein a color dye is added. 5) As a colored dye, it contains at least one compound represented by the following general formula (D).
The image recording medium according to 4).

[0012]

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In the general formula (D), R ₁ and R ₂ each represent a hydrogen atom, an alkyl group or an aryl group. X and Y are a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group,
Represents a substituent selected from an aryloxy group, an amino group, an acylamino group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a sulfo group, and a carboxyl group. 6) The image recording medium according to 1) to 5), which contains at least one compound represented by the following general formula (C) as a colored dye.

[0014]

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In the general formula (C), R represents a hydrogen atom, an alkyl group, an aryl group, an acyl group, a carbamoyl group or a sulfonyl group. M represents a hydrogen atom, an alkali metal, or ammonium. Ar represents an aryl group. n represents an integer of 0 to 3, and m represents 0 or 1. 7) The image recording medium according to 1) to 6), wherein the ink receiving layer contains a polymer compound containing a vinylpyrrolidone unit. 8) The image recording medium according to 1) to 7), wherein at least one layer contains polymethyl methacrylate-based spherical particles having a diameter of 15 µm or more.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The recording medium of the present invention is a resin-coated paper in which the support is coated on both sides of the paper with a resin containing 50% by weight or more of polyolefin. The thickness of the resin layer is desirably not less than 5 μm and not more than 50 μm per side. The thickness of the entire resin-coated paper is not particularly limited, but is preferably 140 μm or more and 250 μm or less in order to obtain a texture close to a photographic print.

The recording medium of the present invention has at least one ink receiving layer on a support. The thickness of the ink receiving layer is 3
The thickness is preferably from 50 μm to 50 μm, and more preferably from 5 μm to 30 μm. The ink receiving layer preferably contains a polymer compound containing a vinylpyrrolidone unit as a mordant polymer. Particularly, a copolymer polymer compound with a vinylimidazole unit is preferably used. When a polymer compound containing a vinylpyrrolidone unit is contained, the coating amount is preferably 0.3 g / m ² or more and 10 g / m ² or less, and 1 g / m ² or more and 5 g / m ² or more.
It is further desirable that m ² or less.

In the coating layer of the recording medium of the present invention, it is preferable to use polyvinyl alcohol as a binder. In particular, it is preferable to use partially saponified polyvinyl alcohol having a saponification degree of 60% or more and 85% or less. The polymerization degree of polyvinyl alcohol is preferably 300 or more and 5000 or less, and more preferably 450 or more and 3000 or less. The content ratio of the mordant polymer to polyvinyl alcohol is preferably 10% or more and 50% or less.

Further, it is desirable to provide a gelatin layer as a protective layer at a position farthest from the support in order to maintain film strength and in manufacturing.

Preferred embodiments of the ink receiving layer include the following structures. 1st layer: polyvinyl alcohol layer containing acetoacetyl-modified polyvinyl alcohol 2nd layer: ink receiving layer containing polyvinyl alcohol having a saponification degree of 70% to 85% and a polymer mordant having a vinylpyrrolidone component Third layer: gelatin as a binder Protective layer containing a matting agent

The recording medium of the present invention has a whiteness of CIE197.
The ranges of L *, a *, b * specified in 6 are as follows. 91 ≦ L * ≦ 98−0.5 ≦ a * ≦ + 1.0−4.5 ≦ b * ≦ −2.5 Furthermore, L *, a *, and b * are preferably in the following ranges. 92 ≤ L * ≤ 98 -0.2 ≤ a * ≤ +0.6-4.0 ≤ b * ≤ -3.0 The whiteness is measured by, for example, Spectro Photomete manufactured by Gretac.
r Built-in light source of D-65, viewing angle 2 by SPM100-II
It can be performed by measuring under the conditions of the filter D-65. CIELAB is described in Section 4-2 of Chapter 4 of the New Color Science Handbook. In order to make the whiteness within the above range, any means may be used.For example, addition of a fluorescent brightener, addition of a colored dye, addition of an inorganic pigment such as titanium oxide or barium sulfate, addition of polymer fine particles And the like. Among them, it is preferable to use a fluorescent whitening agent and / or a colored dye.

In order to keep the whiteness within the above range, it is preferable to use a fluorescent whitening agent represented by the general formula (E). The use of a fluorescent whitening agent in an ink jet recording medium has been used for a long time.
No. 93 is described. In addition, for example, JP-A-8-337045 discloses that the compound of the general formula (E) is effective for improving conveyance failure in a printer. However, it was not disclosed at all that improvement in skin color reproducibility when used in an ink jet recording medium containing a polymer compound containing a vinylpyrrolidone unit in the ink receiving layer. The general formula (E) below
The compound of is described in more detail.

In the general formula [E], X ₂ , X ₃ , Y ₁ and Y ₂ are each a halogen atom such as oxygen, chlorine or bromine;
Alkyl groups (including substituents), aryl groups (including substituents),

[0024]

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Or -OR ₂₅ , wherein R ₂₁ and R ₂₂ are each a hydrogen atom, an alkyl group (including a substituent) or an aryl group (including a substituent), and R ₂₃ and R ₂₄ are an alkylene group (substituted) R ₂₅ represents a hydrogen atom, an alkyl group (including a substituent) or an aryl group (including a substituent),
M represents a hydrogen atom or an alkali metal atom.

The alkyl group represented by R ₂₁ , R ₂₂ and R ₂₅ preferably has 1 to 6 carbon atoms, and the aryl group represented by R ₂₁ , R ₂₂ and R ₂₅ preferably has 6 to 6 carbon atoms. 12
Wherein the alkylene group represented by R ₂₃ and R ₂₄ preferably has 1 to 2 carbon atoms.

The substituents of the alkyl group and aryl group represented by R ₂₁ , R ₂₂ and R ₂₄ and the alkylene group represented by R ₂₃ and R ₂₄ are hydroxy, sulfo, sulfoamino and carboxyamino. Is preferred.

[0028]

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Specific examples of the alkylamino group (for example, methylamino, ethylamino, propylamino, dimethylamino, cyclohexylamino, β-hydroxyethylamino, di (β-hydroxyethyl) amino, β-
Sulfoethylamino, N- (β-sulfoethyl) -N-
Methylamino, N- (β-hydroxyethyl-N-methylamino and the like), or arylamino group (for example, anilino, o-, m-, p-sulfoanilino, o-, m-, p
-Chloroanilino, o-, m-, p-toluidino, o
-, M-, p-carboxyanilino, o-, m-, p-
Hydroxyanilino, sulfonaphthylamino, o-, m
-, P-aminoanilino, o-, m-, p-anidino).

[0030]

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Specific examples of ## STR5 ## include a morpholino group, and specific examples of --OR ₂₅ include an alkoxy group (eg, methoxy, ethoxy, methoxyethoxy, etc.) and an aryloxy group (eg, phenoxy, p-sulfophenoxy, etc.).
Is mentioned.

As the alkali metal atom represented by M,
For example, it is a sodium atom, a potassium atom, or a lithium atom, preferably a sodium atom or a potassium atom.

Among the compounds represented by the general formula [E],
Is preferably a compound X_Two, X_Three, Y ₁And Y_TwoIs all

[0034]

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Or a compound of the formula —OR ₂₅ , the most preferred compound being that one of X ₂ and Y ₁ is —OR ₂₅ and the other is

[0036]

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And one of X ₃ and Y ₂ is -OR
_{When 25 is} the other

[0038]

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Is a compound.

Specific examples include the following compounds, but are not limited thereto.

[0041]

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[0042]

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[0043]

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The compound represented by the general formula [E] can be prepared by a known method, for example, "Fluorescent brightener" edited by Japan Chemical Industry Association.
(Issued August 1981) It can be synthesized by the usual method described on page 8. Also, commercially available products such as Uvitex (trade name of Ciba-Geigy) and Whitex (trade name of Sumitomo Chemical Co., Ltd.) can be obtained. E-9 is particularly preferably used among the exemplified compounds.

The compound represented by the general formula [E] is preferably contained in the ink receiving layer in an amount of 0.1 to 10% by weight, more preferably 0.5 to 5%, from the viewpoint of the effects of the present invention.
% By weight. If it is less than 0.1%, the effects of the present invention cannot be obtained, and if it exceeds 10%, the gloss and transparency of the surface of the receptor layer are undesirably lost.

In order to keep the whiteness within the above range, it is preferable to use a colored dye represented by the general formula (D).

Hereinafter, the compound represented by formula (D) will be described in detail. In the general formula (D), R ₁ and R ₂ each represent a hydrogen atom, an alkyl group, or an aryl group. X and Y are a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group,
Represents a substituent selected from an aryloxy group, an amino group, an acylamino group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a sulfo group, and a carboxyl group. X, Y
May combine with each other to form a ring.

The alkyl group represented by R ₁ or R ₂ may be substituted, and the substituent may be a halogen atom, an alkyl group, an alkenyl group, an aryl group, an acyl group, a carboxyl group, an alkoxycarbonyl group, an aryloxy group. Carbonyl group, carbamoyl group, cyano group, alkoxy group, aryloxy group, hydroxyl group, acyloxy group, amino group, acylamino group, sulfonylamino group, ureido group, urethane group, nitro group, alkylthio group, arylthio group,
Examples thereof include an alkylsulfonyl group, an arylsulfonyl group, a sulfamoyl group, a sulfo group, and a heterocyclic group. Examples of preferred alkyl groups for R ₁ and R ₂ include, for example, methyl, ethyl, isopropyl, n-butyl, n-hexyl, cyclopropyl, cyclohexyl,
2-hydroxyethyl, 4-carboxybutyl, 2-methoxyethyl, 2-diethylaminoethyl, benzyl,
Phenethyl can be mentioned.

The aryl group represented by R ₁ and R ₂ may be substituted, and the substituent may be a halogen atom, an alkyl group, an alkenyl group, an acyl group, a carboxyl group, an alkoxycarbonyl group, an aryloxycarbonyl group. , Carbamoyl group, cyano group, alkoxy group, aryloxy group, hydroxyl group, acyloxy group, amino group, acylamino group, sulfonylamino group, ureido group, urethane group, nitro group, alkylthio group, arylthio group, alkylsulfonyl group, arylsulfonyl group , A sulfamoyl group and a sulfo group. Examples of preferred aryl groups for R ₁ and R ₂ include phenyl, naphthyl, 2,6-dimethylphenyl, 2,4,6-trimethylphenyl, 4-carboxyphenyl, 4-acetamidophenyl, and 3-methanesulfonamidophenyl , 4-
Methoxyphenyl, 3-carboxyphenyl, 3,5-
Examples thereof include dicarboxyphenyl, 4-methanesulfonamidophenyl and 4-butanesulfonamidophenyl. Particularly preferred from the viewpoint of hue is a phenyl group substituted with an alkyl group or an alkoxy group at both the 2- and 6-positions.

An alkyl group (preferably having 1 to 20 carbon atoms) or an aryl group on the alkyl group, alkoxy group, aryloxy group, amino group, acylamino group, acyl group, alkoxycarbonyl group, carbamoyl group represented by X and Y The portion (preferably having 6 to 35 carbon atoms) may further have a substituent described above. Preferred substituents in X and Y are a hydrogen atom, a halogen atom (eg, Cl, Br), an alkoxy group (eg, a methoxy group, a methoxyethoxy group),
Aryloxy group (for example, phenoxy group, 4-chlorophenoxy group), amino group (for example, diethylamino group, hydroxyethylamino group), acyl group (for example, benzoyl group, acetyl group), alkoxycarbonyl group (for example, butoxycarbonyl group), Examples include a sulfo group and a carboxyl group.

The organic dye represented by the general formula [D] can be synthesized by a known method, for example, an ordinary method described in “New Handbook of Dye Handbook” (edited by The Society of Synthetic Organic Chemistry, Japan) (Maruzen, 1970). The amount of the organic dye represented by the general formula (D) is preferably 0.002~0.04g / m ^2, more preferably from 0.005~0.02g / m ^2.

Further, the recording medium of the present invention preferably contains a compound represented by the general formula (C) as a colored dye. Hereinafter, the compound of the formula (C) will be described in detail. In the general formula (C), R represents a hydrogen atom, an alkyl group (preferably having 1 to 20 carbon atoms), an aryl group (preferably having 6 to 35 carbon atoms), an acyl group (preferably having 2 carbon atoms).
-25), carbamoyl group (preferably having 1 to 3 carbon atoms)
5) represents a sulfonyl group (preferably having 1 to 35 carbon atoms). M represents a hydrogen atom, an alkali metal, or ammonium. Ar represents an aryl group (preferably having 6 to 35 carbon atoms including a substituent on the aryl group). n represents an integer of 0 to 3, and m represents 0 or 1.

The alkyl group represented by R has a substituent
And examples of the substituent include R ₁, R_TwoRepresented by
Some of the substituents for the alkyl group are listed.
come. Examples of preferred alkyl groups are methyl, ethyl
Isopropyl, n-butyl, n-hexyl, cyclo
Propyl, cyclohexyl, 2-hydroxyethyl, 4
-Carboxybutyl, 2-methoxyethyl, 2-diethyl
Luminoethyl and the like.

The aryl group represented by R has a substituent
And examples of the substituent include R ₁, R_TwoRepresented by
Some of the substituents for the aryl group may be mentioned.
come. Examples of preferred aryl groups include phenyl, naph
Tyl, 4-methoxyphenyl group, 4-carboxyphenyl
, 4-acetamidophenyl, 3-methanesulfone
Midophenyl, 4-butanesulfonamidophenyl, etc.
Can be mentioned.

An acyl group represented by R, a carbamoyl group,
The sulfonyl group may have an alkyl group, an aryl group, or a heterocyclic group, and the alkyl group, the aryl group, or the heterocyclic group may further have a substituent. Examples of the substituent include those exemplified as the substituent for the alkyl group and the aryl group represented by R ₁ and R ₂ . Preferred examples of the acyl group include benzoyl, acetyl, 4-dodecyloxybenzoyl and the like. Preferred examples of the carbamoyl group include phenylcarbamoyl, 4-acetamidophenylcarbamoyl, naphthylcarbamoyl and the like. Examples of preferred sulfonyl groups include
4-methylphenylsulfonyl, 4-dodecyloxyphenylsulfonyl, butylsulfonyl and the like can be mentioned.

Further, these groups represented by R may combine with another dye to form a dimer. R
Among them, particularly preferred are a hydrogen atom, an aryl group, an acyl group and a sulfonyl group.

The alkali metal represented by M is preferably sodium or potassium. The ammonium represented by M may be unsubstituted or substituted. Preferred examples include unsubstituted ammonium, tetramethylammonium and trimethylbutylammonium.

The aryl group represented by Ar may be substituted, and examples of the substituent include a hydroxyl group, a halogen atom (eg, Cl, Br, F, I), a cyano group, a nitro group,
Carboxyl group, sulfo group, chain or cyclic alkyl group having 1 to 20 carbon atoms (for example, methyl, ethyl, isopropyl, n-butyl, n-hexyl, cyclopropyl, cyclohexyl, 2-hydroxyethyl, 4-carboxybutyl, 2-methoxyethyl, 2-diethylaminoethyl), an alkenyl group having 1 to 20 carbon atoms (for example, vinyl,
Allyl, 2-hexenyl), alkynyl group having 2 to 12 carbon atoms (eg, ethynyl, 1-butynyl, 3-hexynyl), aralkyl group having 7 to 12 carbon atoms (eg, benzyl, phenethyl), aryl having 6 to 20 carbon atoms Groups (eg, phenyl, naphthyl, 4-carboxyphenyl, 4-
Acetamidophenyl, 3-methanesulfonamidophenyl, 4-methoxyphenyl, 3-carboxyphenyl, 3,5-dicarboxyphenyl, 4-methanesulfonamidophenyl, 4-butanesulfonamidophenyl), acyl having 1 to 20 carbon atoms Groups (eg, acetyl, benzoyl, propanoyl, butanoyl), having 2 to 2 carbon atoms
0 alkoxycarbonyl groups (eg, methoxycarbonyl, ethoxycarbonyl), aryloxycarbonyl groups having 7 to 24 carbon atoms (eg, phenoxycarbonyl, naphthoxycarbonyl),

A carbamoyl group having 1 to 24 carbon atoms (for example, unsubstituted carbamoyl, methylcarbamoyl, diethylcarbamoyl, phenylcarbamoyl);
-20 alkoxy groups (e.g., methoxy, ethoxy, butoxy, methoxyethoxy), C6-C24 aryloxy groups (e.g., phenoxy, 4-carboxyphenoxy, 3-methylphenoxy, naphthoxy), 2-carbon atoms
20 acyloxy groups (eg, acetoxy, benzoyloxy), a sulfonyloxy group having 1 to 20 carbon atoms (eg, methylsulfonyloxy, phenylsulfonyloxy),

An amino group having 0 to 30 carbon atoms (eg, unsubstituted amino, dimethylamino, diethylamino, 2-carboxyethylamino), an acylamino group having 1 to 30 carbon atoms (eg, acetamido, benzamido),
20 sulfonylamino groups (e.g., methylsulfonylamino, phenylsulfonylamino, butylsulfonylamino, n-octylsulfonylamino), having 1 to 2 carbon atoms
A ureido group of 0 (eg ureido, methylureido),
A urethane group having 2 to 20 carbon atoms (e.g., methoxycarbonylamino, ethoxycarbonylamino);
0 alkylthio groups (eg, methylthio, ethylthio,
Octylthio),

An arylthio group having 6 to 20 carbon atoms (eg, phenylthio, naphthylthio), an alkylsulfonyl group having 1 to 20 carbon atoms (eg, methylsulfonyl, butylsulfonyl), and an arylsulfonyl group having 7 to 30 carbon atoms (eg, phenylsulfonyl, 2-naphthylsulfonyl), a sulfamoyl group having 0 to 30 carbon atoms (eg, unsubstituted sulfamoyl, methylsulfamoyl, etc.), a heterocyclic group (eg, 2-benzothiazolyl, 4-pyridyl,
Examples thereof include piperidino, 2-furyl, 2-thienyl, 2-pyrrolyl) and arylazo groups having 6 to 30 carbon atoms (eg, 4-acetamidophenylazo, 4-sulfophenylazo).

[0062]

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[0063]

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[0064]

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[0065]

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[0066]

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[0067]

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[0068]

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[0069]

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[0070]

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[0071]

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[0072]

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[0073]

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[0074]

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[0075]

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The organic dye represented by the general formula [E] is publicly available.
A method of knowledge, for example, ed.
(Maruzen, 1970).
Can be synthesized. Use of the organic dye represented by the general formula [E]
The dose is preferably between 0.0001 and 0.002 g / m^Two
And more preferably 0.0001 to 0.001 g.
/ M ^TwoIt is.

The dye used in the present invention can be used without any problem whether it is water-soluble or oil-soluble. When it is water-soluble, it can be directly added as an oil-soluble dispersion (for example, emulsified dispersion, micellar dispersion, etc.).

In the recording medium of the present invention, the water swelling ratio of the entire coating layer provided on the polyolefin layer coated on the support is desirably 100% to 300%, preferably 150% to 250%. It is more desirable that: 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.

An inorganic pigment can be used in combination with the recording material of the present invention. The type of the inorganic pigment is not particularly limited, and any inorganic pigment can be used. For example, silica pigment, alumina pigment, titanium dioxide pigment, zinc oxide pigment, zirconium oxide pigment, mica-like iron oxide, lead white, lead oxide pigment, cobalt oxide pigment, strontium chromate, molybdenum pigment, smectite, magnesium oxide pigment, oxide Examples thereof include calcium pigments, calcium carbonate pigments, mullite, and the like, and one kind or two or more kinds can be used.

By including these inorganic pigments in one of the coating layers, the coating layer can be made porous and the ink absorption speed can be extremely increased. As a result, the image quality is improved, and the problem that the ink is transferred to another paper or another object on which ink is superimposed is solved.

The film surface pH of the recording medium is preferably 3 or more and 9 or less from the viewpoint of storage stability and safety of the recording medium. Particularly preferred is 7 or more and 8.5 or less. Here, the film surface pH is a value obtained by dropping 40 μl of water on the coated surface of the recording medium and measuring the pH one minute later.

As the binder of the mordant-containing layer and other layers constituting the recording medium, hydrophilic binders are preferably used. An example thereof is disclosed in JP-A-62-253159.
No. (26) to (28). Specifically, transparent or translucent hydrophilic binders are preferred, for example, gelatin, proteins or cellulose derivatives such as gelatin derivatives, starch, gum arabic, dextran, natural compounds such as polysaccharides such as pullulan, polyvinyl alcohol, Examples include polyvinylpyrrolidone, acrylamide polymers, and other synthetic polymer compounds. Further, superabsorbent polymers described in JP-A-62-245260 and the like, that is, -COOM or-
A homopolymer of a vinyl monomer having SO ₃ M (M is a hydrogen atom or an alkali metal) or a copolymer of the vinyl monomers or other vinyl monomers (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.

The recording medium of the present invention preferably contains at least one layer of polymethyl methacrylate-based spherical particles having a diameter of 15 μm or more. Known matting agents may 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), alkaline earth metal salts (eg, sulfate, calcium carbonate, etc.), silver halide grains which do not form an image (silver chloride, silver bromide, etc., and a small amount of iodine atoms may be contained as a halogen component. ) And glass. In addition, West German Patent 2,529,321, British Patent Nos. 760,775 and 1,260,772, US Patents 1,201,905, and 2,192,241
No. 3,053,662, 3,062,649
Nos. 3,257,206 and 3,322,555
Nos. 3,353,958 and 3,370,951
No. 3,411,907 and 3,437,484
Nos. 3,523,022 and 3,615,554
Nos. 3,635,714 and 3,769,020
And inorganic matting agents described in JP-A Nos. 4,021,245 and 4,029,504 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 and the like), 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 monomer component of a combination of (meth) acrylate, styrene sulfonic acid and the like 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 Nos. 1,055,713, U.S. Pat. Nos. 1,939,213 and 2,221,873
No. 2,268,662 and 2,322,037
No. 2,376,005, 2,391,181
Nos. 2,701,245 and 2,992,101
No. 3,079,257 and 3,262,782
No. 3,443,946, No. 3,516,832
Nos. 3,539,344 and 3,591,379
Nos. 3,754,924 and 3,767,448
And JP-A-49-106821 and 57-14835.
And the like.

Among them, polymethyl methacrylate, benzoguanamine / formaldehyde condensed polymer (for example, trade name: Eposter; Nippon Shokubai Chemical Co., Ltd .: existing chemical substances 7-31, etc.), polyolefin (for example, flow beads LE-1080, trade name) CL-2080, HE-
5023; manufactured by Iron and Steel Chemical or trade name Chemipearl V-1
00; Mitsui Petrochemical), polystyrene beads (Moltex), nylon beads (Mortex),
AS resin beads (manufactured by Mortex), epoxy resin beads (manufactured by Mortec), polycarbonate resins (manufactured by Mortec) and the like are preferable.

The constituent layers (including the back layer) of the recording medium of the present invention contain silica, particularly colloidal silica, for the purpose of improving adhesion resistance, improving film strength, and improving curl balance. You may. The colloidal silica has an average particle diameter of 7 μm to 500 μm, the main component is silicon dioxide, and may contain alumina or sodium aluminate as a small component. In addition, these colloidal silicas may contain an inorganic base such as sodium hydroxide, potassium hydroxide, lithium hydroxide, or ammonium hydroxide or an organic salt such as tetramethylammonium ion as a stabilizer. 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 Matijevic, Ed., Surface and Colloid Science, No. 6.
Volume 3-100 (1973, John Wiley & Sons). Specific examples of colloidal silica include Ludox from DuPont (EIdopont Nemours & Co, (USA)).
AM, Ludox AS, Ludox LS, Ludox TM, Ludox HS, etc. from Nissan Chemical Co., Ltd. (Tokyo, Japan) under the trade name Snowtex 20, Snowtex C, Snowtex N, Snowtex O, etc. Sy from Monsant Co, (USA)
Ton C-30, Syton 200, etc. and Nalco Chem, C
O (USA) from Nalcoag 1030, Nalcoag 1060, Nalcoag
Commercially available under the trade name such as ID-21-64.
The preferable use amount of the colloidal silica is 0.05 to 5.0, particularly preferably 0.2 to 2.5, in terms of dry weight ratio to the solid content of the constituent layer.

In the present invention, it is preferable to use a germicidal and antibacterial agent for the recording medium 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,
Various antibacterial agents and antibacterial agents such as cyclohexylphenol compounds, imidazole and benzimidazole compounds, sulfamide compounds, active halobene compounds such as chlorinated isocyanuric acid, sodium, chelating agents, sulfite compounds, and penicillins. There are fungicides. In addition, other L. EWest (LEWest), Water Quality Criteria (Water Quality
Criteria) Phot. Sci. And Eng., Vol9, No6 (1965)
Fungicides described in JP-A-57-8542 and 58-10
No. 5145, No. 59-126533, No. 55-111
No. 942 and No. 57-157244; various antibacterial and antibacterial agents described by Hiroshi Horiguchi in "Chemistry of antibacterial and antifungal agents" (published by Sankyo in 1982).

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 (for example, PB Report 19) , 9
21, U.S. Pat. Nos. 2,950,197 and 2,96
No. 4,404, No. 2,983,611, No. 3,2
Nos. 71,175, JP-B-46-40898
And isoxazole-based compounds (for example, those described in U.S. 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-triacrylonitrile-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 19,920,
West German Patent Nos. 1,100,942 and 2,337,41
2, 2,545,722, 2,635,518
Nos. 2,742,308 and 2,749,260
U.S. Pat. No. 3,251,091; U.S. Pat.
Nos. 5,39,644 and 3,490,911), acryloyl (for example, those described in U.S. Pat. No. 3,640,720), carbodiimide ( For example, U.S. Pat. No. 2,938,892
Nos. 4,043,818 and 4,061,499, those described in JP-B-46-38715, and triazines (for example, 2,4-dichloro-6-).
Hydroxy-S-triazine and the like, and also, for example, German Patent Nos. 2,410,973 and 2,553,915
No. 3,325,287, those described in JP-A-52-12722), N-methylols (dimethylol urea, methylol dimethylhydantoin, etc.), dioxane derivatives (2,3 -Dihydroxydioxane, etc.), mucohalic acid type (mucochloric acid, mucophenoxycyclolic acid, etc.), dialdehyde starch, 1-chloro-6-hydroxytriazinylated gelatin, maleimide type, acetylene type, metasulfonic acid ester type hardened Membrane agents can be used. Examples of the polymer hardener include polymers having an aldehyde group described in U.S. Pat. No. 3,396,029 (e.g., copolymers of acrolein);
Research Disclosure No. 17333 (197
8) and the like, a polymer having a dichlorotriazine group described in US Pat. No. 3,623,878, a polymer having an epoxy group described in US Pat. No. 3,623,878, Research Disclosure 1
6725 (1978), U.S. Pat. No. 4,161,40.
7, JP-A-54-65033 and JP-A-56-14252.
4, a polymer having an active vinyl group or a group which can be a precursor thereof, and JP-A-56-66.
No. 841 discloses a polymer having an active ester group. The addition amount of the hardener is optional, but usually, about 0.0% of the constituent materials capable of reacting with the hardener is used.
1-30 wt%, especially 0.1-10 wt%, is suitable.

For the constituent layers of the recording medium, various surfactants can be used for the purpose of coating aid, improving releasability, improving slipperiness, preventing static charge, and the like. Specific examples of the surfactant are described in JP-A Nos. 62-173463 and 62-18345.
No. 7, etc. Further, an organic fluoro compound may be included for the above purpose. Representative examples of the organic fluoro compound include JP-B-57-9053, Nos. 8-17.
Column, JP-A-61-20994, 62-135826
And hydrophobic fluorine compounds such as oily fluorine compounds such as fluorine oil or solid fluorine compound resins such as ethylene tetrafluoride resin.

In the constituent layers of the recording medium, a high-boiling organic solvent can be used for the purpose of coating aid, improving releasability, improving slipperiness, and preventing static charge. Specifically, JP-A-62-2
No. 53159, pp. (25) and 62-245253. Further, for the above purpose,
Various silicone oils (all silicone oils from dimethyl silicone oil to modified silicone oil obtained by introducing various organic groups into dimethyl siloxane) can be used. As examples thereof, various modified silicone oils described in "Modified Silicone Oil" Technical Document P6-18B issued by Shin-Etsu Silicone Co., Ltd., particularly carboxy-modified silicone (trade name: X-22-3710) are effective. JP-A-62-215953 and 63-46
No. 449 is also effective.

The constituent layers (including the back layer) of the recording medium can contain various polymer latexes for the purpose of improving film physical properties such as dimensional stability, curl prevention, adhesion prevention, and film crack prevention. . Specifically, Japanese Patent Application Laid-Open No. Sho 62
-245258, 62-136648, 62
Any of the polymer latexes described in JP-A-110066 can be used. In particular, when a polymer latex having a low glass point transition (40 ° C. or less) is used for the mordant layer, the mordant layer can be prevented from cracking and curl can be improved, and if a polymer latex having a high glass transition point is used for the back layer, An anti-curl effect is obtained.

In the constituent layers of the recording medium, an anti-fading agent may be used. Anti-fading agents include, for example, antioxidants, ultraviolet absorbers, or certain metal complexes. Antioxidants include, for example, chroman compounds, Craman compounds, phenol compounds (eg, hindered phenols), hydroquinone derivatives, hindered amine derivatives, and spiroindane compounds. Also, Japanese Unexamined Patent Publication No.
The compound described in -159644 is 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. 2784) and JP-A Nos. 54-48535 and 62-136641.
And the compounds described in JP-A-61-88256 and the like.
Further, ultraviolet absorbing polymers described in JP-A-62-260152 are also effective. As metal complexes, U.S. Pat. Nos. 4,241,155 and 4,245,018 Nos. 3 to
Column 36, column 4, 254, 195 columns 3 to 8, JP-A-62-174741, JP-A-61-88256 (27)
To (29), JP-A-63-199248, JP-A-1-7
5568 and 1-74272.

Examples of useful discoloration inhibitors are described in JP-A-62-21.
No. 5272, pages (125) to (137). The anti-fading agent for preventing fading of the dye formed on the recording medium may be contained in the recording medium in advance, or may be contained in ink or the like and supplied from the outside to the recording medium. . The above antioxidants, ultraviolet absorbers, and metal complexes may be used in combination with each other.

In the present invention, the support for the recording medium is not particularly limited.
Synthetic polymers (films) are mentioned. Specifically, it is made of polyethylene terephthalate, polycarbonate, polyvinyl chloride, polystyrene, polypropylene, polyimide, celluloses (for example, triacetylcellulose), or films containing pigments such as titanium oxide, and polypropylene. Synthetic paper made from synthetic resin pulp such as polyethylene and natural pulp, Yankee paper, baryta paper, coated paper (especially cast-coated paper),
Metals, cloths, glasses and the like are used. These can be used alone or as a support laminated on one or both sides with a synthetic polymer such as polyethylene. In addition, Japanese Patent Application Laid-Open No. 62-253159
The supports described in pages (29) to (31) can be used. A hydrophilic binder, a semiconductive metal oxide such as alumina sol or tin oxide, carbon black, or another antistatic agent may be applied to the surface of these supports.

In the present invention, a particularly preferred support is a paper or plastic support laminated on both sides with a polyolefin (eg, a homopolymer such as polyethylene, polystyrene, polyethylene terephthalate, polybutene, or a copolymer of any combination thereof). However, a white pigment such as titanium oxide and zinc oxide, and a coloring dye such as cobalt blue, ultramarine blue and neodymium oxide are preferably contained in the polyolefin.

The white pigment which can be contained in the polyolefin on the coating surface side is not particularly limited, but is preferably titanium oxide or zinc oxide, particularly preferably anatase type titanium oxide, and 50% for improving dispersibility. It is preferable to use together with the following zinc oxide. The amount of the white pigment contained in the polyolefin is preferably 5% by weight or more, more preferably 10 to 50% by weight, and particularly preferably 15% by weight.
To 30% is preferred.

There are no particular restrictions on the tinting pigment that can be included in the surface-side polyolefin,
300 ° C for cobalt blue, ultramarine, neodymium oxide, etc.
Those that can withstand the above coating temperatures are desirable.
The amount of the tinting pigment used is 0.1 to 3% by weight based on the white pigment. In order to control the surface reflection characteristics, the selection and the amount of the tinting pigment are particularly important. Even in pigments referred to as ultramarine blue, colors vary greatly depending on the manufacturer and the production number. Therefore, it is desirable to mix and use various pigments so as to obtain necessary surface reflection characteristics. When the support is a polyethylene laminated paper containing a white pigment such as titanium oxide, the back layer is preferably designed to have an antistatic function and to have a surface resistivity of 10 12 Ω · cm or less.

Although the image forming method of the present invention is effective for ink jet printing, it can be used for general systems including dye release and reception, such as sublimation type thermal transfer printing and dye diffusion transfer printing, and xerography. . There is no limitation on the type of inkjet printing, and the image forming method of the present invention can be used regardless of whether it is a continuous type or an on-demand type. The type of the ink jet 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. Recent advances in ink-jet systems have been remarkable, for example, a method of ejecting a large number of low-density inks called photo inks in a small volume, a method of improving image quality by using a plurality of inks having substantially the same hue and different densities, a colorless method Many new methods are proposed, such as a method using transparent ink,
Has been put to practical use. Although the image forming method of the present invention is preferably used for any of these methods, the improvement effect is remarkable particularly in a printer that prints a large amount of ink having a high print speed and a low density to form an image close to a photograph. Be demonstrated.

[0099]

Example 1 Pulp mixing ratio LBKP / NBSP = 6/4 Polyethylene was laminated on both sides of a high-quality paper (density: 1.053, thickness: 152 μm) at 300 ° C. by an extrusion coating method. It was created. 0.923 density on the back
A mixture of titanium having a surface treated as a white pigment and ultramarine (blue and red) manufactured by Daiichi Kasei Co., Ltd. as a coloring pigment was used. The thickness of the front polyethylene was 36 μm, and the thickness of the back polyethylene was 27 μm.
A sample 101 was prepared by coating the following coating layer on the above resin-coated support. The main purpose of addition of each compound is shown in parentheses, but the purpose of addition is not limited thereto.

First layer: Film thickness about 0.8 μm Polyvinyl alcohol PVA405 (binder) manufactured by Kuraray Co., Ltd. 0.6 g / m ² acetoacetyl-modified polyvinyl alcohol 0.1 g of Gohsefimer Z-200 manufactured by Nippon Synthetic Chemical Industry Co., Ltd. / m ² Compound P-17 (polymer mordant) 0.1 g / m ² Compound W-04 (surfactant) 0.01 g / m ² Compound F-08 (preservative) 0.001 g / m ²

Second layer: film thickness of about 8 μm polyvinyl alcohol PVA405 (binder) manufactured by Kuraray Co., Ltd. 4.9 g / m ² Compound P-17 (polymer mordant) 3.2 g / m ² Compound E-9 (fluorescent brightening) Compound) 0.04 g / m ² Compound W-04 (surfactant) 0.04 g / m ²

Third layer: film thickness of about 0.7 μm alkali-treated gelatin 0.13 g / m ² fine particles of polymethyl methacrylate (average particle size of about 20 μm matting agent) 0.25 g / m ² compound D-6 (cyan dye ) 0.01 g / m ² compound C-3 (magenta dye) 0.0002 g / m ² compound W-04 (surfactant) 0.02 g / m ² compound W-09 (surfactant) 0.02 g / m ² Compound F-08 (preservative) 0.002 g / m ² Compound H-02 (hardener) 0.08 g / m ²

[0103]

Embedded image

Samples 102 to 109 shown in Table 1 were prepared by changing the amounts of the second layer compound E-9 and the third layer compounds D-6 and C-3.

25 ° C. for one week after applying samples 101 to 109
Was cut into a postcard size of 14.5 cm in length and 10 cm in width, and an image was printed using an ink jet printer PM-700C manufactured by Epson Corporation and evaluated. Evaluation of color reproducibility and the like was carried out by a total of ten evaluation specialists specializing in photographic evaluation at Fuji Photo Film Co., Ltd.'s Ashigara Research Laboratories on a scale of 1 to 5. The evaluation criteria are as follows. 5 points Very excellent 4 points Excellent 3 points Average, almost practically available 2 points Practically problematic 1 point Inferior 0 points Inferior The evaluation results are as shown in Table 1. The sample of the present invention is excellent in skin color reproducibility.

[0106]

[Table 1]

Example 2 Compound P of the first layer and the second layer of sample 101 of Example 1
-17 was changed to equimolar compounds P-201 and P-202 to prepare Samples 201 and 202, respectively. Samples 201 and 202 were evaluated in the same manner as in Example-1. As a result, Sample 201 had excellent skin color reproduction,
The glossiness was low and the image quality was unacceptable for photographic quality. Sample 202 had excellent skin color reproduction, but also had low gloss, was remarkably inferior in light resistance, and discolored during one month after being stuck to a wall near a window, which was unacceptable as a photographic print.

[0108]

Embedded image

Example 3 In place of compound E-9 in the second layer of sample 101, compound U was used.
Sample 301 was prepared by adding equimolar V-01. When the evaluation was performed in the same manner as in Example 1, the whiteness was L * =
At 89.5, a * = 0 and b * =-2.8, the skin color reproduction was unpleasant and unfavorable.

[0110]

Embedded image

Example 4 Sample 401 was prepared by changing the matting agent of polymethyl methacrylate in the third layer of Sample 101 to the same weight average grain size of 12 μm. Sample 401 was inferior in gloss to sample 101 and was not desirable as a photographic print.

[0112]

As described above, according to the present invention, it is possible to provide an ink jet image recording medium having gloss and smoothness close to those of a photographic print, improved color reproduction, and capable of reproducing natural light flesh color. . Further, according to the present invention, it is possible to provide an ink jet image recording medium having excellent image storability.

Claims (8)

[Claims] 1. An ink jet recording medium having an ink receiving layer provided on at least one side of a support, wherein the support is a resin-coated paper in which both sides of the paper are coated with a resin, and the whiteness of an unprinted portion is CIE1976. An ink jet recording medium, wherein the specified L *, a *, and b * are in the following ranges. 91 ≦ L * ≦ 98−0.5 ≦ a * ≦ + 1.0−4.5 ≦ b * ≦ −2.5 2. The image recording medium according to claim 1, wherein a fluorescent whitening agent is added. 3. The image recording medium according to claim 1, wherein at least one compound represented by the following general formula (E) is contained as a fluorescent whitening agent. Embedded image 4. The image recording medium according to claim 1, wherein a color dye is added. 5. The image recording medium according to claim 1, comprising at least one compound represented by the following general formula (D) as a colored dye. Embedded image In the general formula (D), R ₁ and R ₂ are each a hydrogen atom,
Represents an alkyl group or an aryl group. X and Y each represent a substituent selected from a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryloxy group, an amino group, an acylamino group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a sulfo group, and a carboxyl group. 6. The image recording medium according to claim 1, comprising at least one compound represented by the following general formula (C) as a colored dye. Embedded image In the general formula (C), R represents a hydrogen atom, an alkyl group, an aryl group, an acyl group, a carbamoyl group, or a sulfonyl group. M represents a hydrogen atom, an alkali metal, or ammonium. Ar represents an aryl group. n represents an integer of 0 to 3, and m represents 0 or 1. 7. The image recording medium according to claim 1, wherein the ink receiving layer contains a polymer compound containing a vinylpyrrolidone unit. 8. The image recording medium according to claim 1, wherein at least one layer contains polymethyl methacrylate spherical particles having a diameter of 15 μm or more.