JP2002264474A - Ink jet recording sheet and method for producing the same - Google Patents

Abstract

(57) [Summary] An ink jet ink having the glossiness of a commercially available art-coated paper, high print density, excellent ink absorbency, and excellent crack strength generated when a sheet is folded. Provide a recording sheet. In one embodiment, one or more ink-receiving layers and a gloss-developing layer are sequentially laminated on a support, and the coating composition of the gloss-developing layer comprises organic polymer fine particles having an average particle diameter of 200 nm or less;
An ink jet recording sheet using an ionizing radiation curable compound containing two or more ethylenic double bonds in one molecule and a release aid. In particular, it is preferable that the release aid is a higher fatty acid salt, and the organic polymer fine particles are crosslinked and anionic or cationic. Further, it is preferable that the ink receiving layer contains a cationic colloid particle, a cationic pigment dispersant or a cationic dye fixing agent in order to improve the ink absorption and the print density.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording sheet for recording using an aqueous ink, which has an excellent ink absorbency, a high print density, and a high print density comparable to that of a commercially available art-coated paper. The present invention relates to an ink jet recording sheet having a glossiness, and further to an ink jet recording sheet having a crack strength in addition to those characteristics, and a method for producing the same.

[0002]

2. Description of the Related Art In an ink jet recording system, fine droplets of ink are caused to fly according to various operating principles and adhere to a recording sheet such as paper, thereby recording images and characters. It has features such as easy multi-coloring, great flexibility of recording pattern, no need for development and fixing, and as a recording device for various figures including Chinese characters and color images.
It is rapidly spreading in various applications. Furthermore, an image formed by the multi-color ink jet method can obtain a record comparable to multi-color printing by a plate making method or printing by a color photographic method. Because it is cheaper than by technology, it is being widely applied to the field of full-color image recording.

[0003] The recording sheet used in this ink jet recording system has a high density of print dots, a bright and vivid color tone, and the ink absorbs quickly so that the ink flows or bleeds even when the print dots overlap. It is required that the print dots do not smear, that the diffusion of print dots in the horizontal direction is not unnecessarily large, and that the periphery is smooth and not blurred.

[0004] In order to solve these problems, several proposals have conventionally been made. For example, JP-A-52-530
No. 12 discloses an ink jet recording paper in which a low-size base paper is wetted with a paint for surface processing. JP-A-55-5830 discloses an ink-jet recording sheet provided with an ink-absorbing coating layer on the surface of a support, and JP-A-55-51583 and JP-A-56-157. Japanese Patent Application Laid-Open No. 55-11829 discloses an example of using a non-colloidal silica powder as a pigment in a coating layer. It has been disclosed.

[0005] Generally, an ink jet recording sheet is provided with an ink receiving layer having ink absorption characteristics to which a porous pigment is applied to control color and sharpness for determining image quality, and to improve color reproducibility and image reproducibility. We are improving. The ink receiving layer having ink absorbency needs to have many voids in the ink receiving layer in order to absorb and retain the ink. However, the ink-receiving layer having many voids becomes opaque because light incident on the ink-receiving layer is scattered or hindered from being transmitted, and the image becomes whitish because light hardly reaches the ink that has penetrated into the voids. And the color reproducibility and the color density decrease. In addition, since the ink receiving layer having many voids has a porous surface, it is difficult to obtain high gloss.

As an ink jet recording sheet having high gloss, for example, JP-A-61-197285 discloses a method in which a porous ink receiving layer is formed on a transparent support, and an image formed on the ink receiving layer is formed. A method of observing from the support side has been proposed. Japanese Patent Application Laid-Open No. Hei 3-215081 discloses that an image formed on a dye-adsorbing layer is formed by sequentially laminating a dye-adsorbing layer made of porous alumina hydrate and a solvent-absorbing layer made of porous finely-divided silica on a transparent support. A method of observing from the support side has been proposed. However, in these methods, when printing an image, it is necessary to perform image processing to be a mirror image,
Further, the support to be used is limited to those having transparency.

JP-A-2-13986 discloses a method of casting after treating with an aqueous solution containing a cationic polymer electrolyte, and JP-A-2-74587 uses colloidal silica for improving gloss. A method of casting after treatment with an aqueous solution containing a cationic polymer electrolyte has been proposed. However, the use of a cationic polymer electrolyte causes the surface of the printed portion to be roughened because the cationic polymer electrolyte present on the surface is re-dissolved in the ink when printing, and the gloss of the printed portion and the image The sharpness tends to decrease.

For the purpose of imparting gloss, there are recording papers, films, and the like coated with a resin that absorbs ink by dissolution and swelling, but those that attempt to absorb ink by dissolution and swelling of such a resin include: Although gloss can be obtained, absorption and drying of the ink are slow, and there is a problem that stains and bleeding due to ink transfer occur.

[0009] The process for imparting gloss is generally performed by using a calender such as a super calender or a gloss calender, and smoothing the surface of the coating layer by passing paper between rolls under pressure or temperature. However, when calendering is performed under a high linear pressure for the purpose of imparting gloss to the ink jet recording sheet, the gloss improves, but the voids in the coating layer decrease, the ink absorption becomes slow, and the absorption capacity becomes insufficient. There is a problem that ink overflows from the ink. For this reason, in the calendering process, the conditions must be selected within the range of the allowable ink absorption capacity, and at present, it is difficult to cope with the current technology to obtain ink absorption and gloss. .

JP-A-8-169175 proposes an ink jet recording sheet having high gloss and excellent scratch resistance by using colloidal particles and an ionizing radiation-curable compound in a gloss developing layer. In order to obtain a high printing density, an ink-jet recording sheet having transparency by applying inorganic colloid particles such as fine silica or alumina sol having an average particle diameter of primary particles of 5 to 50 nm produced by a gas phase method. A method for forming the fine inorganic material is described. However, if the ratio of fumed silica or alumina sol (pseudo-boehmite) to the ionizing radiation-curable compound in the gloss-developing layer is not increased, the ink absorption is poor. A coating layer having a high content of colloidal particles has a problem that the coating film is very likely to crack when cured.

The publication also discloses that the glossy layer contains organic particles having an average particle diameter of 300 nm or less, but the fine organic particles improve the print density, glossiness and cracks. However, the ink absorption is lower than that of the inorganic colloid particles, and the improvement has been a problem.

Further, the addition of an ionizing radiation-curable silicone compound having a water-repellent action to adjust the contact angle of the surface of the gloss-developing layer is disclosed, but the addition of such a compound undesirably lowers the ink absorption. .

[0013]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an ink having excellent ink absorbency, high print density and gloss, excellent color reproducibility and image reproducibility in printing with an aqueous ink,
It is still another object of the present invention to obtain an ink jet recording sheet having a sufficient cracking strength, particularly, an ink jet recording sheet for full color recording which requires a glossiness.

[0014]

Means for Solving the Problems The present inventors have made intensive studies on the ink jet recording sheet, and as a result, have come to invent the ink jet recording sheet of the present invention.

That is, in the ink jet recording sheet of the present invention, in the ink jet recording sheet having an ink receiving layer provided on a support, at least one ink receiving layer is provided on the support, and the average particle diameter is 200 nm as a main component.
It is characterized in that the following organic polymer fine particles and a gloss developing layer composed of an ionizing radiation curable compound containing two or more ethylenic double bonds in one molecule and a release aid are sequentially laminated. is there.

When the release aid is a higher fatty acid salt, it is possible to obtain an ink jet recording sheet having excellent ink absorbency and excellent gloss.

In the ink jet recording sheet of the present invention, the coating composition for the glossy layer is crosslinked and has an average particle diameter of 200 n which is anionic or cationic.
It is preferable that organic polymer fine particles of m or less are used as a main component.

In the ink jet recording sheet of the present invention, the coating composition of the ink receiving layer preferably contains, as a main component, an inorganic pigment having a particle size of 1.0 μm or less and 30% by volume or more.

Further, the inorganic pigment is a cationic colloid particle.

The ink receiving layer preferably contains a cationic pigment dispersant or a cationic dye fixing agent.

As a result of repeated studies focusing on the material permeability of ionizing radiation, a gloss-enhancing layer coating composition was coated on a mirror-finished metal roll or a highly smooth synthetic resin film, and the solvent was dried. After being pressed against the surface of the ink receiving layer provided on the body, the glossy layer is cured by irradiating ionizing radiation while the coating composition has plasticity, and then peeled off from the roll or the film. This proved that a high gloss ink jet recording sheet was obtained.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an ink jet recording sheet of the present invention will be described in detail. In general, in order to obtain good ink absorbency and dye fixability, which are features of an ink jet recording sheet, a method of applying a coating layer mainly containing a porous inorganic pigment has been adopted. However, since the inorganic pigment is present as secondary particles, it has a large particle diameter, and it is difficult to functionally generate glossiness.
Even if the smoothness is improved by performing a calendering treatment under high linear pressure conditions, not only the gloss suitable for the purpose of the present invention is not obtained, but also the voids are reduced, the ink absorbency is reduced and the ink jet recording sheet is reduced. You will lose features.

However, in the ink jet recording sheet of the present invention, the printing surface of the recording sheet is a two-layer coating layer of an ink receiving layer (at least one layer) and a gloss developing layer, so that the ink receiving layer Maintains ink absorption function and improves glossiness by separating the function to give glossiness with a glossy layer composed of organic polymer fine particles having an average particle diameter of 200 nm or less, an ionizing radiation curable compound and a release aid. It has become possible to balance the conflicting properties of ensuring ink absorption.

The improvement in glossiness was studied in a direction in which organic polymer fine particles were applied as a composition for the ink receiving layer, because they were obtained with a pigment having a small particle size. However, even if a coating composition containing organic polymer fine particles as a main component is applied directly to a support as an ink receiving layer, the problem of ink overflow occurs because the ink absorption capacity is small. or,
In the support mainly composed of wood pulp, the occurrence of feathering in which ink is diffused along the wall surface of the pulp fiber and the occurrence of ink loss caused by the ink reaching the back surface,
There was a decrease in print density, and further, the desired gloss could not be obtained.

Based on these findings, it is possible to avoid the above-mentioned problems and provide a gloss by providing a coating composition containing organic polymer fine particles as a main component on the surface of an ink receiving layer as a gloss developing layer. It was found that characteristics dependent on the sharpness and color of the receiving layer were obtained.

Since the average particle diameter of the organic polymer fine particles applied to the glossy layer according to the present invention is extremely small, that is, 200 nm or less, light in the low wavelength region of visible light (about 400 nm) is hardly scattered. As a result, the transparency of the resulting image is also improved, and a glossy layer of inorganic colloidal particles such as fumed silica or alumina fine particles, which is usually used to achieve both glossiness and ink absorbency characteristics. In the case of adding to the toner, the coating layer is peeled off when the addition amount is increased in order to improve the glossiness and the ink absorbency, but the image quality is excellent without such defects.

The fine organic polymer particles having an average particle diameter of 200 nm or less are preferably crosslinked, and more preferably anionic or cationic. Such organic polymer fine particles generally contain at least one monomer selected from the group consisting of alkyl acrylates, alkyl methacrylates, styrene and styrene derivatives with one or two carbon-carbon double bonds in the molecule.
It can be obtained by emulsion polymerization using an emulsifier having at least two (preferably at least two) emulsifiers. As such organic polymer fine particles, a microgel described in JP-A-5-254251 can be suitably used. This publication describes that the use of microgels in thermosensitive recording paper improves sticking resistance and moisture resistance.However, in thermosensitive recording, ink is applied to a recording sheet as in the present invention. Instead of printing by jetting, printing is performed by heating and belongs to different technical fields.

As examples of the alkyl acrylate and the alkyl methacrylate, alkyl (meth) acrylates having 1 to 18 carbon atoms in the alkyl are preferable, such as methyl (meth) acrylate and (meth) acrylic acid. Ethyl, n-propyl (meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth)
Stearyl acrylate can be mentioned. Examples of styrene and styrene derivatives include styrene, α-methylstyrene and vinyltoluene.

In addition to the above monomers, monomers copolymerizable with the above monomers may be used in an amount of 50% by weight or less based on the total amount of the monomers. For example, anionic vinyl monomers of acrylic acid, methacrylic acid, maleic anhydride, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid; dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate and quaternary ammonium Cationic vinyl monomers such as vinyl monomers having salts; and (meth) acrylic acid 2-
Examples include nonionic vinyl monomers such as hydroxyethyl, 2-hydroxypropyl (meth) acrylate and (meth) acryloyloxyphosphate.

In addition to the above monomers, a crosslinkable vinyl monomer may be used in an amount of 5% by weight or less based on the total amount of the monomers. For example, bifunctional monomers such as ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, hexamethylenebis (meth) acrylamide, and divinylbenzene; 1,3,5-triacryloylhexahydro-S-triazine And trifunctional monomers such as triallyl isocyanurate; tetramethylolmethanetetraacrylate and N, N, N ',
Examples include tetrafunctional monomers such as N'-tetraallyl-1,4-diaminobutane.

In the emulsifier having one or more (preferably two or more) carbon-carbon double bonds in the molecule, examples of the carbon-carbon double bond include (meth) allyl group, -Propenyl group, 2-methyl-1-propenyl group, vinyl group, isopropenyl group and (meth) acryloyl group. Among these, a (meth) acryloyl group is preferred. The emulsifier has a cationic group or an anionic group (hydrophilic group) for exhibiting an emulsifying action together with a hydrophobic group. The cationic group is preferable because it has a large function of holding the coloring material of the ink and thus improves the water resistance of the ink receiving layer. Examples of the cationic group or anionic group (hydrophilic group) include -COOH, -COO
_{M, -OSO 3 M, -N (} R 1) (R 2) (R 3), - O
_{H, -PO (OM) 2,} (- O) 3 P, (- O) 2 P (O
H)-, -OP (OH) ₂ , -OPO (OM) ₂ , (-
_{O) 2 PO (OM),} (- O) 3 PO and - (OR) -
[However, M represents Na or K, and R ¹ , R ² and R ³
Each independently represents a hydrogen atom, alkyl, aralkyl or hydroxyalkyl, and R represents ethylene or propylene]. Among them, -N (R ¹ ) (R ² ) (R ³ ) [R ¹ , R ² and R ³
Each independently represents a hydrogen atom, alkyl or hydroxyalkyl, and at least one group is alkyl or hydroxyalkyl]. The emulsifier plays a role of a usual emulsifier and a role of a polymerizable (crosslinkable) monomer, and thus the surface of the obtained organic polymer fine particles has the above-mentioned cationic group or anionic group. Of course, it may be present inside the organic polymer fine particles.

Examples of the emulsifier include sulfosuccinates of polyoxyethylene alkyl ether having two or more carbon-carbon double bonds in the molecule,
A sulfate salt of a polyoxyethylene alkyl ether having two or more carbon double bonds in a molecule, a sulfosuccinate of a polyoxyethylene alkyl phenyl ether having two or more carbon-carbon double bonds in a molecule, A sulfate salt of polyoxyethylene alkylphenyl ether having two or more carbon double bonds in a molecule, an acidic phosphoric acid (meth) acrylate dispersant,
Oligoester (meth) acrylate phosphate esters or alkali salts thereof, and polyalkylene glycol derivative oligoester poly (meth) acrylates having a hydrophilic alkylene oxide group can be exemplified. These commercially available products include KAYA
MER PM-2 (Nippon Kayaku Co., Ltd.), New Frontier A-229E (Daiichi Kogyo Seiyaku Co., Ltd.), New Frontier N-250Z (Daiichi Kogyo Seiyaku Co., Ltd.) and the like. it can.

When an emulsifier having two or more carbon-carbon double bonds in the molecule is used, the emulsifier having one carbon-carbon double bond in the molecule is used in a proportion of not more than 60% by weight of the total emulsifier. May be included. In addition, the emulsifier having one or more carbon-carbon double bonds in the molecule may include a usual anionic emulsifier, a cationic emulsifier, and a nonionic emulsifier. The amount of the emulsifier having one or more carbon-carbon double bonds in the molecule is usually 1 to 20 parts by weight, and 3 to 10 parts by weight, based on 100 parts by weight of the total amount of the monomers. preferable.

The organic polymer fine particles of the present invention can be obtained by a known emulsion polymerization method using the above monomers. For example, the above-mentioned emulsifier and water are charged into a reaction vessel, and after adding and emulsifying the above-mentioned monomer, a radical polymerization initiator is added, and the monomer is polymerized by heating under stirring to obtain the above-mentioned organic polymer fine particles. be able to.
The addition of the vinyl monomer may be either collective dropping or divided dropping. In addition, the concentration of such a monomer is such that the solid content concentration in the finally obtained reaction liquid (dispersion liquid) is usually 2%.
It is adjusted to be 0 to 50% by weight, preferably 30 to 45% by weight. The pH during the reaction is preferably in the range of 3 to 9, and the reaction temperature may be any temperature at which the polymerization initiator is activated, and is usually 40 to 90 ° C, and 50 to 8
0 ° C. is preferred. The reaction time is usually 30 minutes to 2 hours.

Examples of the radical polymerization initiator include persulfates such as potassium persulfate and ammonium persulfate; water-soluble radical polymerization initiators such as hydrogen peroxide and water-soluble azo initiators; And a reducing agent such as sodium hydrogen sulfite and sodium thiosulfate. Redox-based polymerization initiators are preferred. The amount of the radical polymerization initiator to be added is preferably 0.05 to 5% by weight based on the total amount of the monomers,
Particularly, 0.1 to 3% by weight is preferable. Further, in order to make the obtained organic polymer fine particles transparent ultrafine particles, it is preferable to carry out the above polymerization in the presence of a transition metal ion as a polymerization accelerator. The organic polymer fine particles obtained by the emulsifier thus obtained exist on the surface in a state where the emulsifier is bonded to the particles by polymerization, and therefore, the surface thereof has an anionic group or a cationic group (hydrophilic group). ) Will be present. Therefore, dyes and pigments in the ink can be easily adsorbed on the surface thereof, and anionic groups, cationic groups, and the like can work effectively. Such hydrophilic groups are also present inside the organic polymer fine particles depending on the type and amount of the emulsifier used and the reaction method.

Further, in the organic polymer fine particles applied to the gloss-developing layer of the present invention, an anionic group and a cationic group (hydrophilic group) are present on the surface thereof,
The dye component in the ink can be fixed in the glossy layer by the electric interaction.

The ionizing radiation curable compound forming the glossy layer in the ink jet recording sheet of the present invention is 1
It is essential that the molecule contains two or more ethylenic double bonds and is hydrophilic. Here, examples of the ethylenic double bond include a vinyl group, an acryloyl group, a methacryloyl group, an alicyclic epoxy group and the like. Unsaturated polyester having such a functional group at a terminal or a side chain, modified unsaturated Polyester, acrylic polymer,
An acrylic oligomer, an acrylic monomer, a methacrylic polymer, a methacrylic oligomer, a methacrylic monomer or a polymer having a vinyl-type unsaturated bond, an oligomer and a monomer, an epoxy compound, and the like can be the ionizing radiation-curable compound in the present invention. However, a compound having an acryloyl group is particularly preferred because of its excellent ionizing radiation curability. In order for the ionizing radiation-curable compound having the above structure to have hydrophilicity, a hydroxyl group, a carboxyl group, a secondary amine,
It is necessary to contain a polar group such as a quaternary amine or a quaternary ammonium base, or a hydrophilic unit such as ethylene oxide, diethylene oxide, morpholine, or pyrrolidone. Here, when the ionizing radiation-curable resin compound is monofunctional, crosslinking of the ionizing radiation-curable compound is difficult to proceed, so that the hardness of the glossy layer becomes insufficient, and dissolution and swelling during printing are reduced. It cannot be completely prevented, the gloss of the printed portion is reduced, and the scratch resistance is not sufficiently improved. or,
If the ionizing radiation-curable compound is not hydrophilic, the ink absorbency is significantly reduced, causing ink overflow and bleeding.

As such an ionizing radiation-curable compound, commercially available ones can be suitably used. Hereinafter, typical commercially available ionizing radiation curable compounds corresponding to the above items will be exemplified, but of course, the present invention is not limited thereto.

Kayarad PEG 400DA, Kayarad R-167, PET-30, Sartomer SR-230,
Sartomer SR-268, Sartomer SR-344, Sartomer SR-444 (Nippon Kayaku, Kayarad and Sartomer series), NK ester A-200,
NK ester A-400, NK ester A-600, N
K ester A-TMM-3, NK ester A-TMM-
3L (above, Shin-Nakamura Chemical, NK ester series),
Aronix M-240, Aronix M-245, Aronix M-205, Aronix M-210 (above, Toagosei Aronix series), 3EG-A, 4
EG-A, 9EG-A, BP-4EA, PE-3A (these are light acrylate series manufactured by Kyoeisha Yushi Kagaku Kogyo), PE-200, PE-300, PE-400, E
P-22, BPE4, TMP-3, PET-3, C-1
615, C-1615M (Daiichi Kogyo Seiyaku, New Frontier Series)

Among the above-mentioned hydrophilic ionizing radiation-curable compounds, those compounds containing an ethylene oxide segment in the molecule are particularly preferred from the viewpoint of ink absorption. The ethylene oxide segment may be a plurality of continuous segments, or may be configured with other segments interposed.

The compounding amount of the ionizing radiation-curable compound per 100 solid parts by weight of the organic polymer fine particles is 10 to 70 solid parts by weight, and more preferably 20 to 50 solid parts by weight. Here, if the compounding amount of the particles is less than 10 solid parts by weight, the binder property of the ionizing radiation-curable compound is inferior, so that the strength of the gloss-developing layer is lowered and not only the sufficient scratch resistance is not obtained, but also the gloss Is also undesirably reduced. On the other hand, when the amount exceeds 70 solid parts by weight, the void-free film portion formed by the ionizing radiation-curable compound becomes too large, resulting in poor ink absorbability.

In the method for producing an ink jet recording sheet of the present invention, the glossy layer coating composition is coated on a mirror-finished metal roll or a highly smooth synthetic resin film, the solvent is dried, and then provided on a support. Pressure bonding with the ink receiving layer surface,
After the coating composition has plasticity, it is irradiated with ionizing radiation to cure the glossy layer, and then is peeled off from the roll or the film. If the releasability is poor when the glossy expression layer is peeled off, a high glossy glossy expression layer cannot be obtained, and in some cases, the coating film of the glossy expression layer may be peeled off and the quality may be significantly impaired. Such release aids generally include stearic acid, palmitic acid, saturated carboxylic acids such as lauric acid, unsaturated carboxylic acids such as oleic acid,
Aluminum stearate, calcium stearate,
Higher fatty acid salts such as zinc stearate, magnesium stearate, ammonium stearate, paraffin,
Examples include waxes such as polyethylene and carbana wax, amides of higher fatty acids, higher fatty acid esters of monohydric or polyhydric alcohols, and so-called silicones such as organopolysiloxanes. When the agent is contained in the glossy layer, the compatibility with the aqueous ink is particularly good, and there is no adverse effect on the ink absorbability, and a glossy layer with high gloss can be obtained.

The compounding amount of the releasing aid per 100 parts by weight of the organic polymer fine particles is 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight. Here, if the amount of the release aid is less than 0.1 solid parts by weight, the release property is insufficient and a glossy layer having high gloss cannot be obtained, and if it exceeds 10 solid parts by weight, It is not preferable because ink absorbency is poor, ink overflows or bleeds, or contaminants are contaminated.

Further, in the gloss developing layer of the present invention, the curability of a hydrophilic ionizing radiation curable compound and an ionizing radiation curable silicon compound containing two or more ethylenic double bonds in one molecule is determined. For the purpose of adjusting and stabilizing the ink absorbability, if necessary as long as the present invention is not impaired,
A monofunctional hydrophilic ionizing radiation curable compound can be added. As the monofunctional hydrophilic ionizing radiation curing, commercially available ones can be suitably used, for example,
N, N-dimethylacrylamide, acryloylmorpholine, N, N-dimethylaminopropylacrylamide, N, N-dimethylaminoethyl acrylate, dimethylaminoethyl acrylate methyl chloride quaternary salt,
N-dimethylaminopropyl acrylamide methyl chloride quaternary salt (all manufactured by Kojin), Kayarad R-128H, Kayarad R-564 (all manufactured by Nippon Kayaku, Kayarad series), Aronix M-101, Aronix M-
102, Aronix M-114, Aronix M-15
0, Aronix M-154, Aronix M-530
0, Aronix M-5400, Aronix M-55
00, Aronix M-5600, Aronix M-5
700 (Toa Gosei Co., Aronix series),
NK ester AMP-10G, NK ester AMP-2
0G, NK ester AMP-60G, NK ester AM
P-90G (above, manufactured by Shin-Nakamura Chemical Co., Ltd., NK ester series) and the like.

The gloss-developing layer of the present invention contains a fluorescent whitening agent, an ultraviolet absorber and a fluorescent whitening agent as long as the effects of the present invention are not impaired.
Antioxidants, light stabilizers, radical polymerization initiators, surfactants, lubricants, cationic dye fixing agents, pigment dispersants, thickeners, flow improvers, defoamers, foam inhibitors, release agents , Foaming agent,
Various additives such as penetrants, coloring dyes, coloring pigments, preservatives, anti-binders, water-proofing agents, wet paper strength enhancers, and dry paper strength enhancers can also be added. Here, the fluorescent whitening agent to be added to the gloss-developing layer is not particularly limited, but a fluorescent whitening agent containing a thiophene skeleton excellent in radiation resistance, weather resistance, etc. is particularly preferable, and was also recorded. In order to improve the storage stability of an image, it is particularly preferable to add an ultraviolet absorber to the glossy layer of the present invention. Examples of such an ultraviolet absorber include phenyl salicylate and pt
salicylic acid-based ultraviolet absorbers such as tert-butylphenyl salicylate and p-octylphenyl salicylate;
2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-
Octoxybenzophenone, 2-hydroxy-4-doxyloxybenzophenone, 2,2'-dihydroxy-
Benzophenone-based ultraviolet absorbers such as 4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-methoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, 2- (2′-hydroxy-
5′-methylphenyl) benzotriazole, 2-
(2′-hydroxy-5′-tert-butylphenyl) benzotriazole, 2- (2′-hydroxy-
3,5′-di-tert-butylphenyl) benzotriazole, 2- (2′-hydroxy-3′-tert-)
Butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy -3 ', 5'-di-
tert-aminophenyl) benzotriazole, 2-
(2′-hydroxy-4′-octoxyphenyl) benzotriazole, 2- [2′-hydroxy-3′-
(3 ″, 4 ″, 5 ″, 6 ″ -tetrahydrophthalimidomethyl) -5′-methylphenyl] benzotriazole, 2,2-methylenebis [4- (1,1,3,3
Benzotriazole-based ultraviolet absorber such as 3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol, 2-ethylhexyl-2-cyano-
Typical examples are cyanoacrylate-based ultraviolet absorbers such as 3,3'-diphenylacrylate and ethyl-2-cyano-3,3'-diphenylacrylate, and water-soluble ultraviolet absorbers and emulsified ultraviolet absorbers. Can be cited.

The blending amount of the ultraviolet absorber in the gloss developing layer of the ink jet recording sheet of the present invention is appropriately determined depending on the ultraviolet absorbing capacity of each ultraviolet absorbing agent, the coating amount of the gloss developing layer, and the like. The amount is 0.01 to 10%, more preferably 0.1 to 5%, based on 100 parts by weight of the organic ponomer fine particles.

The ionizing radiation for curing the ionizing radiation-curable compound in the gloss-developing layer of the ink jet recording sheet of the present invention generally includes ultraviolet rays, α rays, β rays, and γ.
Ray, X-ray, electron beam, etc .;
Since rays or X-rays are accompanied by a problem of danger to the human body, ultraviolet rays and electron rays, which are easy to handle and are widely used industrially, are effective.

In the present invention, when an electron beam is used,
The irradiation electron dose is preferably in the range of about 0.1 to 10 Mrad. Here, if it is less than 0.1 Mrad, the curing effect is insufficient because a sufficient irradiation effect cannot be obtained, and if it exceeds 10 Mrad, the support is deteriorated, which is not preferable. As a method of irradiating the electron beam, a scanning method, a curtain beam method, or the like can be used, and the acceleration voltage of the electron beam is preferably about 100 to 300 KV. When irradiating with an electron beam, if the oxygen concentration in the atmosphere is high, the curing of the ionizing radiation-curable compound is hindered, so that nitrogen, helium,
In general, irradiation is performed in an atmosphere in which replacement with an inert gas such as carbon dioxide is performed and the oxygen concentration is suppressed to 600 ppm or less, more preferably 400 ppm or less.

When ultraviolet rays are used in the present invention, it is necessary to incorporate a sensitizer into the adhesive layer. Specific examples thereof include acetophenones such as di- or trichloroacetophenone, and benzophenone. , Michler's ketone, benzyl, benzoin, benzoin alkyl ether, benzyl dimethyl ketal, tetramethylthiuram monosulfide, thioxanthones, azo compounds, etc. It is selected from the viewpoint of sex and the like. The use amount of the sensitizer is usually about 1 to 5% by weight based on the ionizing radiation-curable compound. Further, a storage stabilizer such as hydroquinone may be used in combination with the sensitizer. As the light source, for example, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, a xenon lamp, a tungsten lamp, and the like are used.

The coating amount of the glossy layer in the present invention is 1 to 20 g / m ² , more preferably 3 to 10 g, as a dry solid content.
/ M ² . The gloss-generating layer is obtained by dissolving or dispersing the organic polymer fine particles, the ionizing radiation-curable compound and the release aid in water or an organic solvent, or when the ionizing radiation-curable compound becomes a dilutable monomer or oligomer. Can be coated on a mirror-finished metal roll or a high gloss synthetic resin film using a conventionally known coating method without using a solvent. Examples of such a coating method include a blade method, an air doctor method, a squeeze method, an air knife method, a reverse roll method, a gravure roll and transfer roll method, a bar method, and a curtain method.

Further, when the coating composition for the gloss-developing layer soaks into the ink receiving layer, the voids in the ink receiving layer are buried, so that the ink absorptivity is significantly reduced. By applying the coating composition on a mirror-finished metal roll or a highly smooth synthetic resin film as described above, and drying the solvent of the coating composition before being pressed against the ink receiving layer, Penetration of the coating composition into the ink receiving layer can be significantly suppressed.

The ink-jet recording sheet of the present invention is applied with a coating composition for the glossy layer, dried with a solvent, pressed against the ink-receiving layer on the support, and irradiated with ionizing radiation to form the coating composition. A mirror-finished metal roll for transferring the mirror surface to a glossy layer by peeling after curing is, for example, a steel roll having a very smooth mirror surface finished with hard chrome plating, such as a super mirror roll. And the smoothness is JIS-B-0601
The center plane average roughness Ra specified in (1982) is 0.0
The diameter is about 3 to 0.1 μm, and the diameter is 0.3 to 2.
It is about 0 m.

The high-smooth synthetic resin film includes, for example, polyethylene terephthalate, polypropylene, polyvinyl alcohol, polyethylene, polyvinyl chloride,
A film produced by uniaxially or biaxially stretching a thermoplastic resin such as polyvinyl acetate, ethylene / vinyl alcohol copolymer, ethylene / vinyl acetate copolymer, and the like. 0601 (198
The center surface average roughness Ra defined in 2) is 0.03 to 0.
The haze specified in JIS-K-6714 is about 0 to 5%, and the thickness is about 5 to 100 μm. As such a high-smooth synthetic resin film, when irradiated with ionizing radiation, a film which has a small decrease in various physical properties such as bendability, tearability and coloring degree is good, and a film which can withstand repeated use is preferable. Judging from such a viewpoint, the most appropriate high smooth synthetic resin film is a polyethylene terephthalate film,
More preferably, it is an antistatic polyethylene terephthalate film produced by biaxial stretching.

The ink jet recording sheet according to the present invention
The 75-degree specular glossiness measured in accordance with IS Z8741 is 25% or more, and preferably 30 to 70%. When the 75-degree specular glossiness on the recording surface of the ink jet recording sheet is 25% or more, it is equivalent to or higher than the level of a commercially available art-coated paper, and the glossiness sensuously recognized is good.

Next, the ink receiving layer will be described. Since the organic polymer fine particles themselves do not have a capacity to absorb the ink solvent component, the ink solvent component permeates the glossy layer and penetrates the ink receiving layer. In the ink receiving layer, even if the ink solvent component diffuses in the surface direction or penetrates in the depth direction, the dye component is not included, so that the color and sharpness are not affected. The amount of voids required for simultaneously functioning and fixing becomes unnecessary. However, if the permeation of the ink solvent component in the ink receiving layer is slowed, the ink will stay in the glossy layer and the ink will diffuse, so that the permeation of the ink solvent component must be fast.

The rate of penetration is related to the coating structure of the ink receiving layer, and the coating structure depends on the particle size of the inorganic pigment to be applied. The penetration of the ink becomes faster due to the smaller pore size. The ink receiving layer according to the present invention has a primary particle diameter of several nm.
If the coating composition is composed mainly of a porous inorganic pigment obtained by aggregating or assembling particles of several hundred nm, a sufficient penetration speed can be secured. In particular, when the organic polymer fine particles in the gloss developing layer are cationic or anionic, only the permeation of the solvent component in the ink into the ink receiving layer may be considered, and the particle diameter is 1.0 μm.
When the following particles are mainly composed of an inorganic pigment of 30% by volume or more, it is possible to ensure a sufficient solvent penetration rate. In addition, the inorganic pigment includes not only a porous inorganic pigment having a primary particle diameter of several hundreds nm or less, but also one of the known pigments described below that corresponds to the present invention.
More than one kind can be used.

The ink receiving layer made of a coating composition containing the inorganic pigment as a main component is provided between the support and the adjoining gloss-developing layer. It is a coating layer that absorbs. The solvent component is removed from the gloss developing layer by the ink receiving layer, and the dye fixing property is accelerated, and the problem of ink overflow can be avoided.

Also, among the above-mentioned inorganic pigments applied to the ink receiving layer in the present invention, cationic colloid particles are preferable. Since the gloss-developing layer composed of a coating composition containing organic polymer fine particles as a main component has no capacity to absorb ink sufficiently, if there is an ink-receiving layer that absorbs ink adjacent to the gloss-developing layer, Will pass through the glossy layer and move to the ink receiving layer. However, when the ink receiving layer is composed of a coating composition containing cationic colloid particles as a main component, the dye component in the ink is captured and fixed by the colloid particles, and the solvent component is located below the ink receiving layer. Move to the support. Therefore, when the support is composed of a composition mainly composed of wood pulp,
It is possible to absorb ink in the voids formed by the pulp. In particular, since wood pulp is hydrophilic, it is possible to quickly absorb ink.

By providing the ink receiving layer so that the amount of the cationic colloid particles becomes 1.0 g / m ² or more, it is possible to exhibit ink fixing property. It is also possible to apply a known inorganic pigment. The amount of coating is also related to the texture of the ink jet recording sheet. If the texture of the coated paper is desired, the texture can be obtained by increasing the coating amount of the ink receiving layer. In addition, when the coating amount is reduced to obtain the texture of base paper or general paper, or when the dye component in each color ink is specifically captured for the purpose of controlling the color, a cationic pigment dispersant or It is also possible to use a cationic dye fixing agent in combination.

Further, by using a cationic pigment dispersant or a cationic dye fixing agent comprising a secondary amine, a tertiary amine and a quaternary ammonium salt in the ink receiving layer,
Insoluble salts are formed with the sulfonic acid group, carboxyl group, amino group, etc. in the water-soluble direct dye or water-soluble acid dye, which is the dye component of the ink, so that the ink is fixed in the voids in the ink receiving layer, and the ink is fixed. The color is improved. In addition, it has a function of suppressing the flow of ink (water resistance) due to water dripping or moisture absorption due to the formation of insoluble salts.

The ink receiving layer according to the present invention preferably contains a water-soluble adhesive. When the adhesive is present, the adhesiveness at the interface between the gloss developing layer and the ink receiving layer is developed, and the adhesiveness at the interface is improved. Although the reason for the development of the adhesiveness is not clear, water is used as a dispersion medium in the coating composition of the ink receiving layer. Penetrate into the layer, redissolve the water-soluble adhesive in the ink receiving layer, adhere to the glossy layer,
It is considered that the strength at the interface is secured.

The mixing amount of the water-soluble adhesive in the ink receiving layer is 3 to 70 parts by weight with respect to 100 parts by weight of the inorganic pigment.
The amount is preferably 5 to 50 parts by weight, and if it is less than 3 parts by weight, the coating layer strength in the ink receiving layer is insufficient, and if it exceeds 70 parts by weight, the absorbability of the ink penetrating and permeating through the glossy layer is reduced. . The coating amount of the ink receiving layer varies depending on the required gloss, ink absorbency, and type of the support.
g / m ² or more. It is also possible to provide one or more coating layers between the ink receiving layer and the support.

The water-soluble adhesive compounded in the ink receiving layer according to the present invention includes: starch derivatives such as oxidized starch, etherified starch and phosphate esterified starch; cellulose derivatives such as carboxymethylcellulose and hydroxyethylcellulose; Gelatin, soybean protein, polyvinyl alcohol or derivatives thereof; polyvinylpyrrolidone, maleic anhydride resin, conjugated diene copolymer latex such as styrene-butadiene copolymer, methyl methacrylate-butadiene copolymer; acrylate and methacrylate Acrylic polymer latex such as acrylic polymer such as polymer or copolymer; vinyl polymer latex such as ethylene vinyl acetate copolymer; or functional group-containing monomer such as carboxy group of these various polymers Functional group modified polymer by monomer Water-based adhesives such as thermosetting synthetic resins such as melamine resins and urea resins; acrylic acid esters such as polymethyl methacrylate; methacrylic acid ester polymer or copolymer resins; polyurethane resins, unsaturated polyester resins, and vinyl chloride -Synthetic resin adhesives such as vinyl acetate copolymer, polyvinyl butyral, and alkyd resin.

Further, the ink receiving layer contains, as an additive,
Dye fixing agents, pigment dispersants, thickeners, flow improvers, defoamers, defoamers, release agents, foaming agents, penetrants, coloring dyes, coloring pigments, fluorescent whitening agents, ultraviolet absorbers, An antioxidant, a preservative, an anti-binder, a water-proofing agent, a wet paper strength enhancer, a dry paper strength enhancer, and the like can be appropriately compounded.

In the glossy layer of the present invention, one or more known white inorganic pigments can be used in combination with the organic polymer fine particles. However, the white inorganic pigment generally has a large particle diameter and causes opacity. Although it depends on the particle size of the white inorganic pigment, the weight ratio of the organic polymer fine particles / the white inorganic pigment needs to be 80/20 or more, more preferably 90/10 or more.

Examples of white inorganic pigments that can be used in combination with the gloss developing layer and the ink receiving layer include light calcium carbonate,
Heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica , Colloidal alumina,
Examples thereof include white inorganic pigments such as aluminum hydroxide, alumina, lithopone, zeolite, hydrohaloysite, magnesium carbonate, and magnesium hydroxide.

In order to impart curl aptitude, a back coat layer may be applied to the surface opposite to the ink receiving layer with the support interposed therebetween. Hydrohalosite is preferred.

The support used in the present invention includes LB
Chemical pulp such as KP, NBKP, GP, PGW, RM
P, TMP, CTMP, CMP, mechanical pulp such as CGP, wood pulp such as waste paper pulp such as DIP, and conventionally known pigments as main components, binder and sizing agent or fixing agent, retention agent, cationizing agent, Various additives such as a paper strength agent are mixed using one or more kinds, and base paper manufactured by various apparatuses such as a fourdrinier paper machine, a circular net paper machine, a twin wire paper machine, etc. Also included are base papers provided with a size press and an anchor coat layer, etc., and coated papers such as art paper, coated paper, and cast coated paper provided with a coat layer thereon. Such a base paper and a coated paper may be directly provided with a coating layer according to the present invention,
Machine calendar,
A calendar device such as a TG calendar and a soft calendar may be used. The basis weight of the support is usually from 40 to 200 g / m ² , but is not particularly limited.

As the support, a polyolefin resin layer may be provided on the above-described base paper, or a film material of a synthetic resin such as polyethylene, polypropylene, polyester, nylon, rayon, polyurethane, or a mixture thereof, and It can be applied to a sheet formed by forming a synthetic resin into fibers.

The method of coating or impregnating the ink receiving layer according to the present invention includes various blade coaters, roll coaters, air knife coaters, bar coaters, rod blade coaters,
Various devices such as a curtain coater, a short dwell coater, and a size press can be used on-machine or off-machine. After the coating or impregnation, it is also possible to finish using a calender such as a machine calender, a TG calender, a super calender, and a soft calender.

The aqueous ink referred to in the present invention is a recording liquid comprising the following colorant, liquid medium, and other additives.

The coloring agent is a water-soluble dye such as a direct dye, an acid dye, a basic dye, a reactive dye or a food coloring.

As the solvent for the aqueous ink, water and various water-soluble organic solvents such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, Alkyl alcohols having 1 to 4 carbon atoms such as isobutyl alcohol; amides such as dimethylformamide and dimethylacetamide; ketones or ketone alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyethylene glycol and polypropylene glycol Polyalkylene glycols such as ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexyl Alkylene glycols having 2 to 6 alkylene groups such as lene glycol and diethylene glycol; lower alkyl ethers of polyhydric alcohols such as glycerin, ethylene glycol methyl ether, diethylene glycol methyl (or ethyl) ether and triethylene glycol monomethyl ether; No.

Among these many water-soluble organic solvents,
Polyhydric alcohols such as diethylene glycol, and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl ether and triethylene glycol monoethyl ether are preferred.

Other additives include, for example, a pH adjuster, a metal sequestering agent, a fungicide, a viscosity adjuster, a surface tension adjuster, a wetting agent, a surfactant, and a rust inhibitor.

The ink jet recording sheet according to the present invention is not limited to use as an ink jet recording sheet, but may be used as any recording sheet using a liquid ink at the time of recording.

The ink jet recording sheet according to the present invention can be conveyed in a recording apparatus not only by a cut sheet but also continuously as a web (winding).

[0078]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited to these examples. In the examples, "parts" and "%" indicate absolute dry parts and absolute dry weight unless otherwise specified. The particle diameter shown in the examples is an average particle diameter determined by a dynamic light scattering method.

In the following Examples and Comparative Examples, all the supports were common, and the supports prepared as follows were used.

[Preparation of Support] The support was composed of 80 parts of LBKP (freeness of 400 mlcsf) and NBKP (freeness of 45 ml).
0 mlcsf) 25 parts of pigment having a ratio of light calcium carbonate / heavy calcium carbonate / talc to 10/10 parts per 100 parts of wood pulp composed of 20 parts, 20 parts of commercially available alkyl ketene dimer, and 0.1 parts of commercially available cationic ( Meta)
Acrylamide 0.03 parts, commercially available cationized starch 0.8
After preparing 0 parts and a sulfuric acid band of 0.40 parts, papermaking was performed using a Fourdrinier paper machine with a basis weight of 90 g / m ² .

The ink jet recording sheets produced in each of the examples and comparative examples were evaluated by the following evaluation methods. Measurement and evaluation are based on JIS P811
The test was performed under the environmental conditions specified in 1.

<Gloss on Coated Surface of Gloss Development Layer and after Calendering> The gloss on the coated surface of the gloss development layer is JIS Z8.
According to No. 741, a variable angle gloss meter (VGS-1001DP) manufactured by Nippon Denshoku Industries Co., Ltd. was used. The 75-degree specular glossiness measured in accordance with JIS Z8741 of the ink jet recording sheet of the present invention is 25% or more, and preferably 30 to 70%. When the 75-degree specular glossiness on the recording surface of the ink jet recording sheet is 25% or more, it is equivalent to or higher than the level of a commercially available art-coated paper, and the glossiness sensuously recognized is good.

<Ink Absorption> Using an ink jet recording apparatus (BJC-820J: manufactured by Canon Inc.),
A heavy-color rectangular pattern was printed with cyan ink and magenta ink, and this pattern was visually evaluated according to the following criteria. A: No distortion is observed in the rectangular pattern.
B: Although the rectangular pattern is slightly distorted, the diffusion of the ink in the plane direction cannot be visually recognized. C: The rectangular pattern is distorted, and ink is diffused in the plane direction. A or B evaluation is required for good ink absorbency.

<Print Density> A solid pattern was printed with black ink using the above ink jet recording sheet, and the optical reflection density of the printed portion was measured using a Macbeth RD-918 type. It is to be noted that the deterioration of the color is remarkable when the optical reflection density is less than 1.25.

<Crack Strength> The ink jet recording sheets of Examples and Comparative Examples were folded in two, and peeling of the coating layer at the folded portions was visually evaluated according to the following criteria.
A: There is no peeling of the coating layer. B: There is no peeling of the coating layer, but cracks are found in the folded portions. C: Peeling of the coating layer is observed.
A or B evaluation is required for the crack strength.

Example 1 [Coating of ink receiving layer] The ink receiving layer was applied on the surface of the support. The coating composition of the ink receiving layer was 100 parts of synthetic amorphous silica (Fine Seal X37B: manufactured by Tokuyama Soda Co., Ltd.) and polyvinyl alcohol (PVA117:
Using 30 parts of Kuraray Co., Ltd., 30 parts of colloidal silica (Snowtex-O: manufactured by Nissan Chemical Industries, Ltd.), and 20 parts of a cationic dye fixing agent (Sumirez Resin 1001: manufactured by Sumitomo Chemical Co., Ltd.), solid content concentration 15 As a percentage,
These were prepared. This coating solution was applied and dried on the support by an air knife coater so that the dry coating amount was 10 g / m ² .

[Coating of Gloss Development Layer] Then, a 75 μm biaxially stretched polyethylene terephthalate film (PET-O300, manufactured by Diafoil Hoechst, haze value 0.8)
5%) a cationic organic polymer fine particle 10 as an organic polymer fine particle
% By weight aqueous dispersion (average particle diameter: 52 nm, polystyrene fine particles cross-linked by an emulsifier having two carbon-carbon double bonds and a quaternary ammonium base, trade name "Mist Pearl C-150", Arakawa Chemical Industry Co., Ltd. 100)
Part, ionizing radiation curable compound (Nippon Kayaku, PET-3
0, pentaerythritol triacrylate) 40 parts,
Solid content concentration 35% of 2 parts of calcium stearate dispersion
The aqueous solution was applied and dried with a rod bar so that the dry coating amount was 7 g / m ^2, and was pressed against the ink receiving layer, and an electron beam was applied from the film side under the conditions of an acceleration voltage of 150 KV and an irradiation dose of 2 Mrad. , And the film was peeled off to obtain an ink jet recording sheet of Example 1.

Example 2 Organic polymer fine particles of the gloss-developing layer were made of polystyrene organic particles (L8999, manufactured by Asahi Kasei Kogyo Co., Ltd., average particle diameter: 200 n).
m) was obtained in the same manner as in Example 1 to obtain an ink jet recording sheet of Example 2.

Example 3 The ionizing radiation-curable compound in the glossy layer was prepared from diethylene glycol diacrylate (SR-230, manufactured by Nippon Kayaku).
An ink jet recording sheet of Example 3 was obtained in the same manner as in Example 1 except that the above conditions were satisfied.

Example 4 [Coating of ink receiving layer] The ink receiving layer was applied on the surface of the support. The coating composition of the ink receiving layer was prepared by using alumina hydrate (Cataloid A) as cationic colloid particles.
S-3: Catalyst Kasei Co .; average particle diameter 10 nm) 100
Part, as an adhesive, polyvinyl alcohol (PVA11
7: Kuraray Co., Ltd.) as a main component. With the solid content concentration of this composition being 10%, the composition was applied and dried with an air knife coater so as to have a dry application amount of 8 g / m ² .

[Coating of Gloss Development Layer] Then, a 75 μm biaxially stretched polyethylene terephthalate film (PET-O300, manufactured by Diafoil Hoechst, haze value 0.8)
5%) a cationic organic polymer fine particle 10 as an organic polymer fine particle
% By weight aqueous dispersion (average particle diameter: 52 nm, polystyrene fine particles cross-linked by an emulsifier having two carbon-carbon double bonds and a quaternary ammonium base, trade name "Mist Pearl C-150", Arakawa Chemical Industry Co., Ltd. 100)
Part, ionizing radiation curable compound (Nippon Kayaku, PEG40
0DA, 40 parts of polyethylene glycol 400 diacrylate) and 2 parts of zinc stearate dispersion were dried with a rod bar at a dry coating amount of 7 g /
was applied and dried such that m ^2, and pressed with the above ink-receiving layer, from the film side, the acceleration voltage conditions of 150 kV, after curing the glossy layer by irradiating an electron beam under conditions of irradiation dose 2Mrad The film was peeled off to obtain an ink jet recording sheet of Example 4.

Example 5 [Coating of ink receiving layer] The ink receiving layer was applied on the surface of the support. The coating composition for the ink receiving layer is a needle-shaped cationic colloidal silica obtained by modifying acicular colloidal silica with aluminum oxide hydrate as cationic colloid particles (Snowtex UP-AK (1): NISSAN CHEMICAL Manufactured by Kogyo Co .; 100 parts of an aggregate having an average particle diameter of 10 to 20 nm in width × 50 to 200 nm in length) as an adhesive,
Polyvinyl alcohol (PVA117: Kuraray) 3
0 parts was the main component. The solid content concentration of this composition is 10%
As a dry coating amount of 10 g / m with a gate roll coater.
Coating and drying were performed to give ² .

[Coating of Gloss-Producing Layer] Next, a 75 μm biaxially stretched polyethylene terephthalate film (manufactured by Diafoil Hoechst, PET-O300, haze value 0.8)
5%) a cationic organic polymer fine particle 10 as an organic polymer fine particle
% By weight aqueous dispersion (average particle diameter: 52 nm, polystyrene fine particles cross-linked by an emulsifier having two carbon-carbon double bonds and a quaternary ammonium base, trade name "Mist Pearl C-150", Arakawa Chemical Industry Co., Ltd. 100)
Part, 40 parts of an ionizing radiation-curable compound (manufactured by Nippon Kayaku, ethylene oxide-modified trimethylolpropane triacrylate), and 2 parts of an aluminum stearate dispersion were dried by a rod bar at a dry coating amount of 7 g / m. ² and dried, and pressed against the above-mentioned ink receiving layer, and an acceleration voltage of 150 was applied from the film side.
After irradiating an electron beam under the conditions of KV and an irradiation dose of 2 Mrad to cure the glossy layer, the film was peeled off, and Example 5 was performed.
Was obtained.

Example 6 An ink jet recording sheet of Example 6 was obtained in the same manner as in Example 1 except that silicone oil was used instead of the calcium stearate dispersion as the release aid for the gloss-developing layer.

Comparative Example 1 Comparative Example 1 was carried out in the same manner as in Example 1 except that the organic polymer fine particles in the glossy layer were cationic colloidal silica (manufactured by Nissan Chemical Industries, ST-AK-ZL, average particle diameter: 80 nm). Was obtained.

Comparative Example 2 Comparative Example was carried out in the same manner as in Example 1 except that the organic polymer fine particles of the glossy layer were made of cationic amorphous silica-alumina particles (manufactured by Kasei Kagaku, USB-1, average particle diameter 40 nm). 2 was obtained.

Comparative Example 3 The organic polymer fine particles of the glossy layer were made of polymethyl methacrylate particles (MR-7G, manufactured by Soken Chemical Co., Ltd., average particle size 7.0 μm).
m) was obtained in the same manner as in Example 1 to obtain an ink jet recording sheet of Comparative Example 3.

Comparative Example 4 An ink jet recording sheet of Comparative Example 1 was prepared by coating the ink receiving layer of Example 1 on a support at 17 g / m ² in a dry coating amount without providing a glossy layer. did.

Comparative Example 5 Example 1 was repeated except that the gloss receiving layer was applied directly on the support at a dry coating amount of 17 g / m ² without providing the ink receiving layer.
In the same manner as in the above, an ink jet recording sheet of Comparative Example 2 was obtained.

Comparative Example 6 A gloss developing layer was prepared in the same manner as in Example 1 except that the organic polymer fine particles were removed, to obtain an ink jet recording sheet of Comparative Example 6.

Comparative Example 7 Example 1 was repeated except that the ionizing radiation-curable compound of the glossy layer was phenoxy polyethylene glycol monoacrylate having one ethylenic double bond in one molecule.
In the same manner as in the above, an ink jet recording sheet of Comparative Example 7 was obtained.

[0102]

[Table 1]

As is clear from Table 1, Examples 1 to 6 in which the surface of the support was provided with a gloss-developing layer mainly composed of organic polymer fine particles having an average particle diameter of 200 nm or less were comparable to commercially available art-coated paper. While having gloss, the print density is high and the ink absorbency is excellent. In Example 6 using silicone oil as compared with Examples 1 to 5 using higher fatty acid salts as a mold release aid, the ink absorption and printing density were slightly lowered due to compatibility problems with the aqueous ink, but the average particle diameter was small. Is 200
Satisfactory characteristics were obtained due to the excellent balance of glossiness, ink absorbency, and print density obtained by the combined use of the organic polymer fine particles having a particle size of nm or less and the ionizing radiation curable compound. However, in Comparative Example 1 using fine inorganic colloid particles for the glossy layer,
In No. 2, cracking occurred, and in Comparative Example 3 using polymer particles having a large average particle size of 7.0 μm, the ink absorbency and print density were low. In Comparative Example 4 having no gloss developing layer, both gloss and print density were low, and in Comparative Example 5 having no ink receiving layer and Comparative Example 6 in which no organic polymer fine particles were used in the gloss developing layer, the ink absorbency and print density were low. . 1
In Comparative Example 7 using an ionizing radiation-curable compound having only one ethylenic double bond in the molecule, the strength of the coating film was weak and cracks occurred.

Example 7 [Coating of ink receiving layer] The ink receiving layer was applied on the surface of the support. The coating composition of the ink receiving layer has a thickness of 1.0 μm.
100 parts of kaolin (Ultra White 90: manufactured by Engelhard) having a particle size of 30.2% by volume or less, and 0.1 part of a commercially available polyacrylic acid-based dispersant, a solid content concentration of 7
To a 0% pigment slurry, 7 parts of a commercially available styrene / butadiene latex were added to obtain a pH of 9.5 and a solid content of 6%.
Adjusted to 0%. This coating composition was dried at a coating amount of 15
g / m ² and coated and dried with a blade coater.

[Coating of Gloss Development Layer] Then, a 75 μm biaxially stretched polyethylene terephthalate film (PET-O300, manufactured by Diafoil Hoechst, haze value 0.8)
5%) a cationic organic polymer fine particle 10 as an organic polymer fine particle
% By weight aqueous dispersion (average particle diameter: 52 nm, polystyrene fine particles cross-linked by an emulsifier having two carbon-carbon double bonds and a quaternary ammonium base, trade name "Mist Pearl C-150", Arakawa Chemical Industry Co., Ltd. 100)
Part, ionizing radiation curable compound (Nippon Kayaku, PET-3
0, pentaerythritol triacrylate) 40 parts, calcium stearate dispersion 2 parts solid content concentration 3
A 5% aqueous solution is dried by a rod bar to a dry coating amount of 7 g / m.
^After coating and drying so as to be ² , pressure-bonded to the above-mentioned ink receiving layer, and after curing the glossy layer by irradiating an electron beam from the film side under the conditions of an acceleration voltage of 150 KV and an irradiation dose of 2 Mrad, The film was peeled off to obtain an ink jet recording sheet of Example 7.

Example 8 [Coating of ink receiving layer] The ink receiving layer was applied on the surface of the support. The coating composition of the ink receiving layer has a thickness of 1.0 μm.
100 parts of kaolin (Amazon 88: manufactured by The Caulim da Amasonia) having a particle diameter of 73.3% by volume or less, and 0.2 parts of a commercially available polyacrylic acid-based dispersant, a 70% solid content pigment slurry, A commercially available styrene / butadiene latex (7 parts) was added to adjust the pH to 9.5 and the solid content to 60%. This coating composition was coated and dried with a blade coater so that the dry coating amount was 15 g / m ² .

[Coating of Gloss Development Layer] The same composition as in Example 7 was treated on the surface of the ink receiving layer under the same conditions.
Was obtained.

Example 9 [Coating of ink receiving layer] The ink receiving layer was applied on the surface of the support. The coating composition of the ink receiving layer has a thickness of 1.0 μm.
average particle diameter 65n having a particle diameter of 100 vol.
To 100 parts of colloidal silica (Snowtex AK-ZL: manufactured by Nissan Chemical Industries, Ltd.) was added 7 parts of a commercially available styrene / butadiene latex to adjust the pH to 9.5 and the solids concentration to 45%. This coating composition was dried at a coating amount of 15
g / m ^{2 was applied} and dried using an air knife coater.

[Coating of Gloss Development Layer] The surface of the ink receiving layer was treated with the same composition as in Example 7 under the same conditions.
Was obtained.

Example 10 [Coating of ink receiving layer] The ink receiving layer was coated on the surface of the support. The coating composition of the ink receiving layer is 1.0 μm
A pigment slurry having a solid content concentration of 70%, comprising 100 parts of kaolin (Hydrasperse: manufactured by Huber) having the following particle diameter of 12.3% by volume and 0.1 part of a commercially available polyacrylic acid-based dispersant, was added to a commercially available pigment slurry. A styrene / butadiene latex (7 parts) was added to adjust the pH to 9.5 and the solid concentration to 60%. This coating composition was dried at a coating amount of 20 g / m 2.
Coating and drying were performed with a blade coater to obtain ² .

[Coating of Gloss Development Layer] The same formulation as in Example 7 was treated on the surface of the ink receiving layer under the same conditions.
0 was obtained.

[0112]

[Table 2]

As is clear from Table 2, fine particles of an organic polymer, an ionizing radiation-curable compound and a mold release aid were used as the coating composition for the gloss-generating layer, and 1 was used as the coating composition for the ink-receiving layer. In Examples 7 to 10 in which the coating composition was mainly composed of an inorganic pigment having a particle size of 0.0 μm or less and 30% by volume or more, high print density and gloss were obtained. In particular, in Examples 8 and 9, the ink absorbency is also excellent. In Example 10, the coating composition of the ink receiving layer was 1.
In the case where an inorganic pigment having a particle diameter of 0 μm or less and 12.3% by volume was used, the gloss was slightly low.

[0114]

The ink jet recording sheet of the present invention is
An ink receiving layer and a glossy layer are sequentially laminated on a support. The glossy layer contains polymer fine particles having an average particle diameter of 200 nm or less, and one molecule contains two or more ethylenic double bonds. By using an ionizing radiation-curable compound and a mold release aid, excellent ink absorptivity, high print density is obtained, and an ink jet recording sheet having a high gloss comparable to a commercially available art-coated paper, ,
An ink jet recording sheet having cracking strength in addition to those properties.

Claims (7)

[Claims] 1. An ink jet recording sheet having an ink receiving layer provided on a support, wherein at least one ink is provided on the support.
Layer or more ink receiving layer, average particle size 200 as main component
Ink jet characterized by sequentially laminating an organic polymer fine particle having a particle size of not more than nm and a gloss developing layer comprising an ionizing radiation-curable compound containing two or more ethylenic double bonds in one molecule and a release aid. Recording sheet. 2. The release aid according to claim 1, wherein the release aid is a higher fatty acid salt.
3. The ink jet recording sheet according to item 1. 3. The organic polymer fine particles are cross-linked,
Further, it is anionic or cationic.
3. The ink jet recording sheet according to item 1. 4. The ink-receiving layer according to claim 1, wherein the coating composition has a coating composition of 1.0 μm.
The ink jet recording sheet according to any one of claims 1 to 3, wherein the main component is an inorganic pigment having a particle size of 30% by volume or more. 5. The ink jet recording sheet according to claim 4, wherein the inorganic pigment is a cationic colloid particle. 6. The ink jet recording sheet according to claim 1, wherein the ink receiving layer contains a cationic pigment dispersant or a cationic dye fixing agent. 7. A method for coating a gloss-developing layer coating composition on a mirror-finished metal roll or a highly smooth synthetic resin film, drying the solvent, and pressing the coated ink-receiving layer on the surface of an ink-receiving layer provided on a support. A method for producing an ink jet recording sheet, comprising irradiating ionizing radiation while the coating composition has plasticity to cure the glossy layer, and then peeling off the roll or the film.