JP2001270220A - Ink jet recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording material having photographically high gloss, high ink absorbability and improved preservability. SOLUTION: In the ink jet recording material wherein an ink receiving layer containing inorganic fine particles is provided on a water-resistant support, the ink receiving layer contains inorganic fine particles in an amount of 40% by weight of a hydrophilic binder and at least one thioether compound.

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 material, and more particularly to an ink-jet recording material having high photo-like gloss, excellent ink absorbency, and improved storage stability after printing. It is.

[0002]

2. Description of the Related Art As a recording material used in an ink jet recording system, a pigment such as amorphous silica is coated on a support called a normal paper or an ink jet recording paper by a porous material comprising a water-soluble binder such as polyvinyl alcohol. There is known a recording material provided with an ink absorbing layer.

[0003] For example, Japanese Patent Application Laid-Open No. 55-51583,
Nos. 6-157, 57-107879, 57-10
No. 7880, No. 59-230787, No. 62-160
No. 277, No. 62-184879, No. 62-1833
As disclosed in JP-A-82 and JP-A-64-11877, a recording material obtained by applying a silicon-containing pigment such as silica to a paper support together with an aqueous binder has been proposed.

[0004] Also, Japanese Patent Publication No. 3-56552,
No. 188287, No. 10-81064, No. 10
-119423, 10-175365, 1
Nos. 0-193776, 10-203006, 10
-217601, 11-20300, 11
Japanese Patent Publication Nos. -20306 and 11-34481 disclose the use of vapor-phase synthetic silica fine particles (hereinafter referred to as fumed silica). This fumed silica is an ultrafine particle having an average primary particle diameter of several nm to several tens nm, and is characterized in that high gloss is obtained.
In recent years, with the demand for photo-like recording sheets, glossiness has been increasingly emphasized, and water resistance of polyolefin resin-coated paper (a laminate of a polyolefin resin such as polyethylene on both sides of paper) and polyester film There has been proposed a recording material in which an ink receiving layer mainly composed of fumed silica is provided on a support.

Conventionally, a paper support generally used itself has a role as an ink absorbing layer. However, a water-resistant support such as the above-mentioned polyolefin resin-coated paper is a paper support. Unlike the above, ink cannot be absorbed, so that the ink absorbing property of the ink receiving layer provided on the support is important, and it is necessary to increase the porosity of the ink receiving layer. Therefore, it was necessary to increase the coating amount of the fumed silica and further reduce the ratio of the binder to the fumed silica.

However, a porous recording material using inorganic fine particles such as fumed silica has a problem that a printed image is easily discolored during storage after printing. That is, discoloration due to light and discoloration due to a trace gas in the air are likely to occur, and discoloration due to a trace gas in the atmosphere is a more important problem.

[0007] JP-A-7-314882 discloses compounds such as dithiocarbamic acid and thiocyanic acid, and JP-A-8-25796 discloses a combination of an iodine compound and a thiourea compound, which causes discoloration by a trace gas in the atmosphere. Is described. However, the effect was not sufficient, the discoloration of a white background was caused, and the compound itself had toxicity, so that it was not sufficiently satisfactory.

Japanese Patent Application Laid-Open No. 1-115677 discloses that the problem of yellowing due to adsorption of silica particles of an ink receiving layer by an additive from a contact substance such as a file is solved by using a thioether compound. However, it does not show discoloration due to trace gases in the atmosphere.

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an ink-jet recording material having improved photo-like high gloss, high ink absorption and storage stability.

[0010]

The object of the present invention has been attained by including a thioether compound in an ink receiving layer, and more specifically, ink jet recording having an ink receiving layer containing inorganic fine particles on a water-resistant support. The object was achieved by an ink-jet recording material, wherein the ink receiving layer contained 40% by weight or less of a binder with respect to the inorganic fine particles and at least one thioether compound.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The preferred ink jet recording material of the present invention is one in which the ink is absorbed in the voids formed in the film by the inorganic fine particles, and it is necessary to increase the void volume in order to exhibit high ink absorbency. For this reason, it is necessary to apply a relatively large amount of inorganic fine particles on the support,
The amount of the hydrophilic binder is preferably reduced to increase the porosity.

The inorganic fine particles used in the present invention include:
Known various fine particles such as silica and alumina,
Particularly, silica is preferable. The ink receiving layer preferably contains 8 g / m ² or more of inorganic fine particles, and 10 to 30 g / m ^2.
More preferably, it is used in the range of m ² . If the amount is less than this range, the ink absorbency is poor. The amount of hydrophilic binder is
The content is 40% by weight or less, preferably 35% by weight or less, particularly preferably 10 to 30% by weight, based on the inorganic fine particles. By reducing the ratio of the hydrophilic binder as described above, the ink absorbency is improved, but the storage stability after printing, particularly the gas resistance, tends to decrease, and the present invention is intended to simultaneously satisfy these performances. Features.

In the present invention, the inorganic fine particles constitute the main proportion in the ink receiving layer, that is, 50% by weight or more, preferably 60% by weight or more, more preferably 65% by weight based on the total solid content of the ink receiving layer. It is preferable to contain the above.

[0014] Synthetic silica includes those obtained by a wet method and those obtained by a gas phase method. As wet silica, silica sol obtained by metathesis of sodium silicate with an acid or the like through an ion exchange resin layer, or colloidal silica obtained by heating and aging this silica sol, gelling silica sol, and changing the production conditions Silicic acid such as silica gel in which primary particles of several microns to 10 microns have become siloxane-bonded three-dimensional secondary particles, and those obtained by heating and producing silica sol, sodium silicate, sodium aluminate, etc. And the like.

[0015] The fumed silica is also called a dry method with respect to a wet method, and is generally produced by a flame hydrolysis method. Specifically, a method of making silicon tetrachloride by burning it with hydrogen and oxygen is generally known, but instead of silicon tetrachloride, silanes such as methyltrichlorosilane and trichlorosilane may be used alone or in a silicon tetrachloride. And can be used in a mixed state. The fumed silica is Aerosil from Nippon Aerosil Co., Ltd. and Q from Tokuyama Co., Ltd.
It is commercially available as the S type and can be obtained.

The average particle diameter of the primary particles of the fumed silica particularly preferably used in the present invention is preferably 30 nm or less, and more preferably 15 nm or less in order to obtain higher gloss. More preferably, the average particle size of the primary particles is 3 to 15 n.
m (in particular 3 to 10 nm) a and a specific surface area by BET method is 200 meters ² / g or more (preferably 250~500m ² /
g). The BET method referred to in the present invention is one of the methods for measuring the surface area of a powder by a gas phase adsorption method, and is a method for determining the total surface area of 1 g of a sample, that is, the specific surface area, from an adsorption isotherm. Usually, nitrogen gas is often used as the adsorbed gas, and the method of measuring the amount of adsorption from the change in pressure or volume of the gas to be adsorbed is most often used. The most prominent to represent the isotherm for multimolecular adsorption is
This is a formula of Brunauer, Emmett, Teller, called a BET formula, which is widely used for determining the surface area. The surface area is obtained by calculating the amount of adsorption based on the BET formula and multiplying the area occupied by one adsorbed molecule on the surface.

In the present invention, as the hydrophilic binder used together with the inorganic fine particles, various known binders can be used. However, a hydrophilic binder which has high transparency and can obtain a higher permeability of the ink is preferably used. In the use of the hydrophilic binder, it is important that the hydrophilic binder does not swell at the initial penetration of the ink and does not close the voids.From this viewpoint, a hydrophilic binder having a relatively low swelling property at around room temperature is preferable. Used. Particularly preferred hydrophilic binders are fully or partially saponified polyvinyl alcohols or cationically modified polyvinyl alcohols.

Particularly preferred among polyvinyl alcohols are those partially or completely saponified with a saponification degree of 80 or more. Those having an average polymerization degree of 200 to 5000 are preferred.

As the cation-modified polyvinyl alcohol, for example, as described in JP-A-61-10483, a primary to tertiary amino group or a quaternary ammonium group is added to the main chain or side chain of polyvinyl alcohol. It is a polyvinyl alcohol contained therein.

In the present invention, it is preferable to use a crosslinking agent (hardener) together with the hydrophilic binder. Specific examples of the crosslinking agent include aldehyde compounds such as formaldehyde and glutaraldehyde, ketone compounds such as diacetyl and chloropentanedione, bis (2-chloroethylurea) -2-hydroxy-4,6-dichloro-1,
3,5 Triazine, a compound having a reactive halogen as described in U.S. Pat. No. 3,288,775, divinyl sulfone, a compound having a reactive olefin as described in U.S. Pat. No. 3,635,718, U.S. Pat. 2nd, 73
N-methylol compounds as described in U.S. Pat. No. 2,316, isocyanates as described in U.S. Pat. No. 3,103,437, U.S. Pat. Nos. 3,017,280 and 2,983,
611, carbodiimide compounds as described in U.S. Pat. No. 3,100,704, epoxy compounds as described in U.S. Pat. No. 3,091,537, halogen carboxaldehydes such as mucochloric acid, There are dioxane derivatives such as dihydroxydioxane, and inorganic crosslinking agents such as chromium alum, zirconium sulfate, boric acid and borate, and these can be used alone or in combination of two or more. Among these, boric acid or borate is particularly preferred.

According to the present invention, the storage stability after printing is remarkably improved by using a thioether compound in combination with inorganic fine particles, particularly fumed silica.

The thioether compound used in the present invention is a compound in which an aromatic group is bonded to both sides of a sulfur atom (the following chemical formulas 1 to 3), and an alkyl group (preferably having 4 or more carbon atoms) at both ends sandwiching the sulfur atom. ) (The following chemical formulas 4 to 5).

[0023]

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[0024]

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[0025]

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[0026]

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[0027]

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The content of the ink receiving layer of the thioether compound, 0.1 to 50 mmol / m ² preferably is more preferably 0.2 to 20 mmol / m ^2.

The ink receiving layer of the present invention preferably contains a cationic compound. By using the above compound and a cationic compound in combination, the storage stability is further improved.

Examples of the cationic compound include a cationic polymer and a water-soluble metal compound. Examples of the cationic polymer include polyethyleneimine, polydiallylamine, polyallylamine, and alkylamine polymers, JP-A-59-20696 and JP-A-59-33176.
No. 59-33177, No. 59-155088,
No. 60-11389, No. 60-49990, No. 60
No. 83882, No. 60-109894, No. 62-1
Nos. 98493, 63-49478, 63-115
780, 63-280681, JP-A-1-403
No. 71, No. 6-234268, No. 7-125411
Nos. 1 to 3 described in JP-A-10-193776 and the like.
A polymer having a quaternary amino group and a quaternary ammonium group is preferably used. The molecular weight of these cationic polymers is preferably 5,000 or more, and more preferably 5,000 to 1
About 100,000 is preferable.

The amount of these cationic polymers used is 1 to 10% by weight, preferably 2 to 7% by weight, based on the inorganic fine particles.

The water-soluble metal compound used in the present invention includes, for example, water-soluble polyvalent metal salts. Water-soluble salts of metals selected from calcium, barium, manganese, copper, cobalt, nickel, aluminum, iron, zinc, zirconium, chromium, magnesium, tungsten, and molybdenum. Specifically, for example, calcium acetate, calcium chloride, calcium formate, calcium sulfate, barium acetate, barium sulfate, barium phosphate, manganese chloride, manganese acetate, manganese formate dihydrate, manganese ammonium sulfate hexahydrate, chlorinated chloride Cupric, ammonium copper (II) chloride dihydrate, copper sulfate, cobalt chloride,
Cobalt thiocyanate, cobalt sulfate, nickel sulfate hexahydrate, nickel chloride hexahydrate, nickel acetate tetrahydrate, nickel ammonium sulfate hexahydrate, nickel amidosulfate tetrahydrate, aluminum sulfate, aluminum sulfite, Aluminum thiosulfate, poly aluminum chloride, aluminum nitrate nonahydrate, aluminum chloride hexahydrate,
Ferrous bromide, ferrous chloride, ferric chloride, ferrous sulfate, ferric sulfate, zinc bromide, zinc chloride, zinc nitrate hexahydrate, zinc sulfate, zirconium acetate, zirconium chloride, chloride Zirconium oxide octahydrate, zirconium hydroxychloride, chromium acetate, chromium sulfate, magnesium sulfate, magnesium chloride hexahydrate, magnesium citrate nonahydrate, sodium phosphotungstate, sodium tungsten citrate, 12 tungstophosphate n Hydrate, 12-tungstosilicic acid 26-hydrate, molybdenum chloride, 12-molybdophosphate n-hydrate and the like.

In the present invention, a water-soluble aluminum compound or a water-soluble compound containing a Group 4A element in the periodic table is particularly preferable. As the water-soluble aluminum compound, for example, as an inorganic salt, aluminum chloride or a hydrate thereof, aluminum sulfate or a hydrate thereof, ammonium alum and the like are known. Further, there is a basic polyaluminum hydroxide compound which is an inorganic aluminum-containing cationic polymer. Particularly, a basic polyaluminum hydroxide compound is preferable.

The basic polyaluminum hydroxide compound has a main component represented by the following general formula 1, 2 or 3, for example, [Al ₆ (OH) ₁₅ ] ³⁺ , [Al ₈ (OH) ₂₀ ] ⁴⁺ ,
It is a water-soluble polyaluminum hydroxide stably containing basic and high-molecular polynuclear condensed ions such as [Al ₁₃ (OH) ₃₄ ] ⁵⁺ , [Al ₂₁ (OH) ₆₀ ] ³⁺ , and the like. .

[Al ₂ (OH) _n Cl _6-n ] _m Formula 1 [Al (OH) ₃ ] _n AlCl ₃ Formula 2 Al _n (OH) _m Cl _(3n-m) 0 <m <3n Formula 3

These are water treatment agents under the name of polyaluminum chloride (PAC) from Taki Chemical Co., Ltd., and polyaluminum hydroxide (Paho) from Asada Chemical Co., Ltd. It is marketed by RIKEN GREEN under the name Purachem WT and from other manufacturers for the same purpose, and various grades are readily available. In the present invention, these commercial products can be used as they are,
Some substances have an inappropriately low pH, and in such a case, the pH can be appropriately adjusted and used.

The water-soluble compound containing a Group 4A element in the periodic table is not particularly limited as long as it is water-soluble, but a water-soluble compound containing titanium or zirconium is preferred.
For example, as a water-soluble compound containing titanium, titanium chloride,
Titanium sulfate is a water-soluble compound containing zirconium as zirconium acetate, zirconium chloride, zirconium oxychloride, zirconium hydroxychloride, zirconium nitrate, basic zirconium carbonate, zirconium hydroxide, zirconium ammonium carbonate, zirconium potassium carbonate, zirconium sulfate And zirconium fluoride compounds are known. Some of these compounds have an inappropriately low pH. In such a case, the pH can be appropriately adjusted and used. In the present invention, the term "water-soluble" refers to a condition in which 1% by weight or more is dissolved in water at normal temperature and normal pressure.

In the present invention, the content of the water-soluble metal compound in the ink receiving layer is 0.1 to the inorganic fine particles.
The content is preferably 1 to 10% by weight, more preferably 1 to 5% by weight.

Two or more of the above-mentioned cationic compounds can be used in combination. For example, it is preferable to use a cationic polymer and a water-soluble metal compound in combination.

In the present invention, the surface pH of the ink receiving layer containing the inorganic fine particles is preferably 2 to 6.
Particularly, 3 to 5 are preferable. By combining the compound of the above-mentioned general formula (Chemical Formula 2) with the film surface pH, the storage stability is further improved. The pH of the surface of the ink receiving layer is determined by the method described in J. Org. TAP
This is the surface pH measured after 30 seconds using distilled water according to the method described in PI Paper Pulp Test Method N0.49.

The pH of the ink receiving layer is preferably adjusted at the stage of the coating solution. However, since the pH of the coating solution does not always coincide with the film surface pH in a state where the coating solution has been dried, the coating solution and the film surface may not be adjusted. It is necessary to determine the relationship with pH in advance by experiments or the like in order to obtain a predetermined film surface pH. The pH of the ink receiving layer coating solution is adjusted by appropriately combining an acid or an alkali. Examples of the acid include inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid, and phosphoric acid, and organic acids such as acetic acid, citric acid, and succinic acid. Examples of the alkali include sodium hydroxide, ammonia water, potassium carbonate, and trisodium phosphate. Alternatively, as the weak alkali, an alkali metal salt of a weak acid such as sodium acetate is used.

The ink receiving layer of the present invention can further contain various oil droplets in order to improve the brittleness of the film.
Such oil droplets include hydrophobic high-boiling organic solvents having a solubility in water at room temperature of 0.01% by weight or less (for example, liquid paraffin, dioctyl phthalate, tricresyl phosphate, silicone oil, etc.) and polymer particles ( For example, particles obtained by polymerizing one or more polymerizable monomers such as styrene, butyl acrylate, divinylbenzene, butyl methacrylate, and hydroxyethyl methacrylate) can be contained. Such oil droplets can be preferably used in the range of 10 to 50% by weight based on the hydrophilic binder.

In the present invention, a surfactant can be added to the ink receiving layer. The surfactant used may be any of anionic, cationic, nonionic and betaine types, and may be of low molecular weight or high molecular weight. One or two or more surfactants are added to the ink receiving layer coating solution. When two or more surfactants are used in combination, an anionic surfactant and a cationic surfactant are used in combination. It is not preferable. The addition amount of the surfactant is preferably 0.001 to 5 g with respect to 100 g of the binder constituting the ink receiving layer,
More preferably, it is 0.01 to 3 g.

In the present invention, the ink receiving layer further comprises:
Publicly known coloring dyes, coloring pigments, fixing agents for ink dyes, ultraviolet absorbers, antioxidants, pigment dispersants, defoamers, leveling agents, preservatives, fluorescent brighteners, viscosity stabilizers, pH regulators, etc. Can be added.

Examples of the water-resistant support used in the present invention include polyester resin such as polyethylene terephthalate, plastic resin film such as diacetate resin, triacetate resin, acrylic resin, polycarbonate resin, polyvinyl chloride, polyimide resin, cellophane and celluloid. And resin-coated paper obtained by laminating a polyolefin resin on both sides of paper. The thickness of the water-resistant support used in the present invention is preferably about 50 to 300 μm.

The base paper constituting the resin-coated paper preferably used in the present invention is not particularly limited, and generally used paper can be used, and more preferably, for example, a smooth paper used for a photographic support is used. Base paper is preferred. As the pulp constituting the base paper, natural pulp, recycled pulp, synthetic pulp or the like may be used alone or in combination of two or more. This base paper contains sizing agents, paper strength agents, fillers, antistatic agents, fluorescent whitening agents,
Additives such as dyes are blended.

Further, a surface sizing agent, a surface paper strength agent, a fluorescent whitening agent, an antistatic agent, a dye, an anchoring agent and the like may be coated on the surface.

The thickness of the base paper is not particularly limited. However, it is preferable that the base paper has good surface smoothness such as by applying a pressure by a calender or the like during or after paper making, and the basis weight is 30%. ~250g / m ² is preferred.

As the resin of the resin-coated paper, a polyolefin resin or a resin curable by an electron beam can be used.
The polyolefin resin is a low-density polyethylene, high-density polyethylene, polypropylene, polybutene, a homopolymer of an olefin such as polypentene or a copolymer of two or more olefins such as an ethylene-propylene copolymer and a mixture thereof, Those having various densities and melt viscosity indices (melt index) can be used alone or in combination.

In the resin of the resin-coated paper, white pigments such as titanium oxide, zinc oxide, talc, calcium carbonate, etc., fatty acid amides such as stearamide, arachidic amide, zinc stearate, calcium stearate, stearic acid Aluminum, metal salts of fatty acids such as magnesium stearate, antioxidants such as Irganox 1010 and Irganox 1076, blue pigments and dyes such as cobalt blue, ultramarine blue, cecilian blue, and phthalocyanine blue, cobalt violet, fast violet, and manganese purple It is preferable to add various additives such as magenta pigments and dyes, fluorescent brighteners and ultraviolet absorbers in an appropriate combination.

The resin-coated paper, which is preferably used in the present invention, is produced by a so-called extrusion coating method in which, in the case of a polyolefin resin, a hot-melt resin is cast on a running base paper, and both sides of the resin-coated paper are made of resin. Coated. In the case of a resin that is cured by an electron beam, the resin is applied by a commonly used coater such as a gravure coater or a blade coater, and then irradiated with an electron beam to cure and coat the resin. Further, before coating the resin on the base paper, the base paper is preferably subjected to an activation treatment such as a corona discharge treatment or a flame treatment. The surface (surface) of the support on which the ink receiving layer is applied has a glossy surface, a matte surface, and the like, depending on the application, and the glossy surface is used particularly advantageously. It is not necessary to coat the back surface with a resin, but it is preferable to coat the resin from the viewpoint of curling prevention. The back surface is usually a matte surface, and the front surface or both front and back surfaces can be subjected to an activation treatment such as a corona discharge treatment or a flame treatment as required. The thickness of the resin coating layer is not particularly limited, but is generally 5 to 50 μm thick on the surface or on both sides.

The support in the present invention may be coated with various back coat layers for antistatic properties, transport properties, curling prevention properties, and the like. The back coat layer can contain an inorganic antistatic agent, an organic antistatic agent, a hydrophilic binder, a latex, a curing agent, a pigment, a surfactant and the like in an appropriate combination.

In the present invention, the method for applying the ink receiving layer is not particularly limited, and a known coating method can be used. For example, there are a slide lip system, a curtain system, an extrusion system, an air knife system, a roll coating system, a rod bar coating system, and the like.

In the present invention, the ink jet recording material may be provided with an ink absorbing layer, an ink fixing layer, an intermediate layer, a protective layer and the like in addition to the layer containing fumed silica. For example, a water-soluble polymer layer may be provided as a lower layer, or a swelling layer may be provided as an upper layer.

[0055]

EXAMPLES The present invention will be described below in detail with reference to examples, but the contents of the present invention are not limited to the examples. In addition, a part means a solid content weight part.

Example 1 LBKP (50 parts) and LBSP (50 parts) were used as supports.
Part) of a pulp blend of 120 g / m ² , and a resin composition composed of low-density polyethylene (70 parts), high-density polyethylene (20 parts) and titanium oxide (10 parts) applied to the surface at 25 g / m ^2. And high-density polyethylene (5
0 parts) and a low-density polyethylene (50 parts) resin coating paper prepared by applying 25 g / m ² .

An ink receiving layer coating solution having the following composition was prepared on the above support, and the coating amount of fumed silica was 18 g in solid content.
/ M ² and dried to prepare an ink jet recording sheet. In addition, all the recording sheets were adjusted so that the film surface pH of the ink receiving layer became 4.2.

<Recording sheet 1> Gas-phase silica (average primary particle diameter 7 nm, specific surface area by BET method 300 m ² / g) 100 parts Polyvinyl alcohol 28 parts (trade name: PVA235, manufactured by Kuraray Co., Ltd., degree of saponification) 88%, average polymerization degree 3500) Boric acid 4 parts Amphoteric surfactant 0.3 parts (Product name: SWAM AM-2150, manufactured by Nippon Surfactant)

<Recording Sheet 2> The amount of polyvinyl alcohol in the recording sheet 1 was increased to 45 parts.

<Recording Sheet 3> To the ink receiving layer of the above-mentioned recording sheet 1 was added 5 mmol / m ² of a compound represented by the following formula (6).

<Recording Sheet 4> To the ink receiving layer of the above-mentioned recording sheet 1 was added 5 mmol / m ² of a compound represented by the following formula (7).

<Recording Sheet 5> To the ink receiving layer of the above-mentioned recording sheet 1 was added 5 mmol / m ² of a compound represented by the following formula (8).

<Recording Sheet 6> To the ink receiving layer of the above-mentioned recording sheet 1 was added 5 mmol / m ² of the compound of formula 1 (Adeka Stab AO-23, Asahi Denka Kogyo).

<Recording sheet 7> The ink receiving layer of the recording sheet 1 was coated with the compound represented by the above formula (2) of the present invention (Cipro Kasei SE).
ENOX B. C. S) was added at 5 mmol / m ² .

<Recording Sheet 8> To the ink receiving layer of the recording sheet 1 was added 5 mmol / m ² of the compound of the formula (5) of the present invention (Adeka Stab AO-412S).

[0066]

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[0067]

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[0068]

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Each of the obtained ink jet recording sheets was evaluated for ink absorbency, storage stability after printing (light fastness and gas fastness), and glossiness. Table 1 shows the results.

<Ink Absorption> Using an ink jet printer (PM-770C manufactured by Seiko Epson Corporation),
Print 100% of each of C, M, Y, and PP immediately after printing
The C paper was superimposed on the printing portion and pressed lightly, and the amount of ink transferred to the PPC paper was visually observed and evaluated according to the following criteria. ：: No transfer at all. ×: Transfer.

<Light resistance> CYMK using an ink jet printer (PM-770C manufactured by Seiko Epson Corporation) was used.
Solid printing with each of the following inks, and irradiating at 600 W / m ² for 30 hours with a Suntest CPS photobleaching tester manufactured by Atlas Co., Ltd., and then measuring the density of the printed portion, the image remaining ratio (density after irradiation / before irradiation) Of the CMYK image.
The one with the lowest remaining rate is indicated.

<Gas resistance> After printing, the paper was exposed to air at room temperature for 3 months in the same manner as in the light resistance test, and the density of the printed area was measured. The image remaining rate (density after exposure / density before exposure) was measured. ) Was obtained, and among the CMYK images, the one with the lowest remaining rate was displayed.

<Glossiness> Glossiness was measured according to the method described in JIS P-8142 (Test method for 75 ° specular glossiness of paper and paperboard).

[0074]

[Table 1] 記録 Recording sheet Ink absorptivity Storage (%) Remarks Lightfastness Gasfastness ───────────────────────────── 1 ○ 71 72 Comparison 2 × 74 80 Comparison 3 ○ 80 73 Comparison 4 ○ 79 74 Comparison 5 ○ 7874 Comparison 6 ○ 80 87 Invention 7 ○ 82 90 Invention 8 ○ 81 88 Invention ────────────────────────────

The gloss was 60 to 6 for all recording sheets.
5% showed high gloss.

As is apparent from the above results, storage stability is improved while maintaining high ink absorption by using the thioether compound of the present invention. That is, the present invention
The ink absorptivity and the storability are simultaneously improved, and a photo-like high gloss can be obtained.

Example 2 The fumed silica used in Example 1 had an average primary particle size of 15 n.
The same test was conducted except that m was replaced. As a result, almost the same results were obtained for the ink absorbency and the storage stability, but the glossiness was reduced by 3 to 6%.

Example 3 The recording sheets 6 to 8 of the present invention of Example 1 were further added with a diallylamine hydrochloride-sulfur dioxide copolymer (trade name PAS-92, manufactured by Nitto Boseki) as a cationic compound. Basic polyaluminum hydroxide (Hyurachem W manufactured by Riken Clean Co., Ltd.)
T) are used to create recording sheets 6A to 8A using two copies,
Evaluation was performed in the same manner as in Example 1. Table 2 shows the results.

[0079]

[Table 2] 記録 Recording sheet Ink absorptivity Storage property Light resistance Gas resistance ─── ─────────────────────────── 6A ○ 89 907 A ○ 91 948A ○ 90 92 ───────────────────

The gloss was 60 to 6 for all recording sheets.
5% showed high gloss.

As can be seen from the above results, the storage stability is further improved by using the thioether compound of the present invention in combination with a cationic compound.

[0082]

According to the present invention, a photo-like ink jet recording material having high ink absorption, high gloss and improved storage stability can be obtained.

Claims (4)

[Claims] 1. An ink jet recording material having an ink receiving layer containing inorganic fine particles on a water-resistant support, wherein the ink receiving layer contains a binder in an amount of 40% by weight or less based on the inorganic fine particles and at least a thioether compound. An ink jet recording material comprising one. 2. The ink jet recording material according to claim 1, wherein the inorganic fine particles in the ink receiving layer are fumed silica. 3. The compound according to claim 1, wherein the thioether compound is selected from a compound having an aromatic group bonded to both sides of a sulfur atom and a compound having an alkyl group at both ends of a sulfur atom.
An ink-jet recording material as described above. 4. The ink jet recording material according to claim 1, wherein said ink receiving layer further contains a cationic compound.