JP2001341414A - Inkjet recording materials - Google Patents

Abstract

(57) Abstract: Provided is an ink jet recording material having improved photo-like high gloss, high ink absorption, and storage stability. In an ink jet recording material provided with a porous ink receiving layer containing fumed silica fine particles on a support, the ink receiving layer contains a cationic compound and a thiourea compound, and the film surface pH is increased. Is 3 to 6.

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 vapor-phase silica). This fumed silica is an ultrafine particle having an average primary particle diameter of several nm to several tens of nm, and is characterized by good ink absorbability and high gloss. In recent years, with the demand for photo-like recording sheets, glossiness has been increasingly emphasized,
Proposal of a recording material in which an ink receiving layer mainly composed of fumed silica is coated on a water-resistant support such as a polyolefin resin-coated paper (a laminate of a polyolefin resin such as polyethylene on both sides of the paper) or a polyester film. Have been.

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, an ink jet recording material having a high porosity recording layer using fumed silica fine particles,
Although the ink absorbency is very good, there are problems that it is inferior in water resistance and that a printed image is easily discolored during storage after printing. That is, the recording medium having a void layer of fumed silica has insufficient light resistance, and cannot be solved by the same means as the means for improving light resistance. Not fully resolved.

Japanese Patent Application Laid-Open No. Hei 10-119423 describes that a hydrophilic binder is crosslinked to prevent cracking of a film. However, some compounds may be used even if the binder is crosslinked. However, it may adversely affect the crack.

[0008]

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, high water resistance and storage stability.

[0009]

SUMMARY OF THE INVENTION The object of the present invention is to provide an ink jet recording material having a porous ink receiving layer containing fumed silica fine particles on a support, wherein the ink receiving layer comprises a cationic compound. And a thiourea-based compound, and has a film surface pH of 3 to 6.

[0010]

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 voids formed in the film by the fumed silica fine particles absorb ink, 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, and the amount of the hydrophilic binder is preferably reduced to increase the porosity.

[0011] fumed silica fine particles used in the present invention preferably contain 8 g / m ² or more in the ink-receiving layer, and more preferably employed in the range of 10 to 30 g / m ^2. If the amount is less than this range, the ink absorbency is poor. The amount of the hydrophilic binder is from 10 to 10
40% by weight is preferred. By reducing the ratio of the hydrophilic binder as described above, the ink absorption is improved, but the water resistance and the light resistance and gas resistance after printing are liable to decrease, and the present invention satisfies these performances simultaneously. Things.

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

The fumed silica is also called a dry method as opposed 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 size of the primary particles of the fumed silica used in the present invention is preferably 30 nm or less, and in order to obtain higher gloss, it is preferably 15 nm or less. More preferably, the average particle size of the primary particles is 3 to 15 nm (particularly, 3 to 1 nm).
0 nm) and the specific surface area by the BET method is 200 m ² / g.
The above (preferably 250 to 500 m ² / g) is used. 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 ones for representing multimolecule adsorption isotherms are Brunauer, Emmet
The t and Teller formulas, which are called BET formulas, are 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 fumed silica fine particles, various known binders can be used. However, a hydrophilic binder which has high transparency and can obtain higher ink permeability is preferable. 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 (hardening agent) 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.

[0019] The present invention relates to a method for producing a fumed silica,
By using a cationic compound and a thiourea compound in the ink receiving layer having a film surface pH of 3 to 6, preferably pH 3 to 5.5, the water resistance and the storage stability after printing are remarkably improved. Here, the thiourea-based compound is a compound having at least one structure represented by the following formula 1 in the molecule, and includes a thiourea derivative, a thiosemicarbazide derivative, and a thiocarbohydrazide derivative.

[0020]

Embedded image

The thiourea compound used in the present invention is
Japanese Patent Application Laid-Open No. Sho 61-163886 discloses that the ink jet recording material is improved in water resistance and light resistance. However, the present invention relates to a fumed silica containing a cationic compound and a thiourea compound and having a specific pH range. It has been found that water resistance, light resistance and gas resistance are simultaneously satisfied at a very high level in the ink jet recording material of the fine particle void layer.

The thiourea derivative, thiosemicarbazide derivative and thiocarbohydrazide derivative used in the present invention are preferably represented by the following formulas 1, 2 and 3, respectively.

[0023]

Embedded image

In the formulas 1, 2, and 3, R ₁ , R ₂ ,
R ₃ and R ₄ each represent a hydrogen atom, a substituted or unsubstituted alkyl group, an aryl group, a heterocyclic group, an acyl group, a guanyl group, etc., and R ₁ and R ₃ , R ₁ and R ₂ or R ₃ R ₄ may form a ring.

The following compounds are exemplified as the thiourea compound used in the present invention.

[0026]

Embedded image

[0027]

Embedded image

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

The cationic compound used in the present invention includes, for example, a cationic polymer and a water-soluble metal compound. Examples of the cationic polymer include polyethyleneimine, polydiallylamine, polyallylamine, alkylamine polymer, JP-A-59-20696 and JP-A-5-20696.
Nos. 9-33176, 59-33177 and 59-1
55088, 60-11389, 60-499
No. 90, No. 60-83882, No. 60-109894
No. 62-198493, No. 63-49478,
Nos. 63-115780, 63-280681, JP-A-1-40371, JP-A-6-234268, and 7-
Polymers having primary to tertiary amino groups and quaternary ammonium bases described in JP-A Nos. 125411 and 10-193776 are preferably used. The molecular weight of these cationic polymers is preferably 5,000 or more, more preferably about 5,000 to 100,000.

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, 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 amide sulfate tetrahydrate, aluminum sulfate, aluminum sulfite, Aluminum thiosulfate, polyaluminum 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 used in the present invention is not particularly limited as long as it is water-soluble, but is preferably a water-soluble compound containing titanium or zirconium.
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 preferably 0.1 to 10% by weight, more preferably 1 to 10% by weight, based on the fumed silica fine particles.
~ 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 film surface pH of the ink receiving layer
Is J. This is the surface pH measured after 30 seconds using distilled water according to the method described in TAPPI 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 is dried, the coating solution and the film surface are not 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 may contain various oil droplets for further improving 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:
Various known additives such as color dyes, color pigments, fixing agents for ink dyes, ultraviolet absorbers, antioxidants, pigment dispersants, defoamers, leveling agents, preservatives, fluorescent brighteners, and viscosity stabilizers. Can also be added.

The support used in the present invention is preferably a water-resistant support. As the water-resistant support, a polyester resin such as polyethylene terephthalate, a diacetate resin, a triacetate resin, an acrylic resin, a polycarbonate resin, a polyvinyl chloride, a polyimide resin, a plastic resin film such as cellophane and celluloid, and a polyolefin resin on both sides of paper And resin-coated paper laminated with 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. More preferably, for example, a smooth paper such as that 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 strengthening 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, but it is preferable that the base paper has good surface smoothness, for example, by applying a pressure by using a calender or the like during or after papermaking, and has a basis weight of 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 and calcium carbonate; fatty acid amides such as stearamide and arachidic amide; zinc stearate; calcium stearate; Aluminum, fatty acid metal salts 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 heat-melted resin is cast on a running base paper. 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 provided 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.

[0054]

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 As supports, LBKP (50 parts) and LBSP (50 parts) were used.
Part) of a pulp blend of 120 g / m ² , and a 25 g / m ² resin composition comprising low-density polyethylene (70 parts), high-density polyethylene (20 parts) and titanium oxide (10 parts) is applied to the surface of a 120 g / m ² base paper. And high-density polyethylene (50
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, each recording sheet was adjusted so that the film surface pH of the ink receiving layer was 4.0.

<Recording sheet 1> 100 parts of fumed silica (average primary particle diameter 7 nm, specific surface area 300 m ² / g by BET method) 25 parts of polyvinyl alcohol (trade name: PVA235, manufactured by Kuraray Co., Ltd., degree of saponification) 88%, average degree of polymerization 3500) 4 parts of boric acid 3 parts of diallylamine hydrochloride-sulfur dioxide copolymer (PAS-92, manufactured by Nitto Boseki Co., Ltd.) Basic polyaluminum hydroxide (Hyurachem WT manufactured by Riken Clean Inc.) 3 parts Amphoteric surfactant 0.3 parts (Product name: SWAM AM-2150, manufactured by Nippon Surfactant)

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

<Recording sheet 3> To the ink receiving layer of 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 recording sheet 1 was added 5 mmol / m ² of a compound represented by the following formula (8).

<Recording Sheet 6> The compound (3) of the present invention was added to the ink receiving layer of the recording sheet 1 in an amount of 5 mmol / m ² .

<Recording Sheet 7> The compound (5) of the present invention was added to the ink receiving layer of the recording sheet 1 in an amount of 5 mmol / m ² .

<Recording Sheet 8> The compound (8) of the present invention was added to the ink receiving layer of the recording sheet 1 in an amount of 5 mmol / m ² .

<Recording sheet 9> The compound (13) of the present invention was added to the ink receiving layer of the recording sheet 1 in an amount of 5 mmol / m ² .

<Recording Sheet 10> 5 mmol / m ² of the compound (14) of the present invention was added to the ink receiving layer of the recording sheet 1.

[0067]

Embedded image

[0068]

Embedded image

[0069]

Embedded image

[0070]

Embedded image

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

<Ink Absorbability> 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.

<Water resistance> A fine line having a width of 100 μm
After printing at an interval of m and leaving it for one day, it was placed under conditions of 35 ° C. and 90% relative humidity (RH) for two days, and the bleeding of the fine line was evaluated according to the following criteria. ：: Almost no bleeding, and the interval between thin lines is clear. Δ: There is bleeding, but the space between the fine lines is not completely crushed. X: The thin line is blurred and the interval between the thin lines is lost.

<Light resistance> CYMK using an ink jet printer (PM-770C manufactured by Seiko Epson Corporation) was used.
Solid printing was performed with each of the above inks, and irradiation was performed at 600 W / m ² for 30 hours using a Suntest CPS photobleaching tester manufactured by Atlas Co., Ltd., and the density of the printed area was measured. Of the CMYK images, and the image with the lowest remaining rate among the CMYK images was displayed.

<Gas resistance> After printing in the same manner as in the light resistance test described above, after exposure to air at room temperature for 3 months, the density of the printed portion was measured, and the image remaining ratio (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-degree specular glossiness of paper and paperboard).

[0077]

[Table 1] 記録 Recording sheet Ink absorption Water resistance Storage stability (%) Remarks Light resistance Gas resistance ───────────────────────────────── 1 ○ ○ 74 75 Comparison 2 ○ ○ 80 78 Comparison 3 ○ 8279 Comparison 4 ○ 8277 Comparison 5 ○ 7981 Comparison 6 ６ 9399 Invention 7 ○ 9499 Invention 8 ○ 93 98 Invention 9 ○ 92 98 Invention 10 ○ 95 99 The present invention

The gloss was 60 to 6 for all recording sheets.
5% showed high gloss. The recording sheet 2 was slightly cracked, but the other recording sheets were not cracked.

As is apparent from the above results, the use of the cation compound and the thiourea-based compound improves light fastness and gas fastness while maintaining high ink absorbency and high water fastness. That is, according to the present invention, the ink absorbency, water resistance and storage stability are simultaneously improved, and a photo-like high gloss is 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 In the recording sheet 10 of the present invention of Example 1, the film surface pH
4.5 (recording sheet 11), 5.5 (recording sheet 1)
2), a sample adjusted to 6.5 (recording sheet 13) was prepared, and a recording sheet 14 was prepared by removing the cationic compound from the recording sheet 10. These samples were prepared in Example 1.
Was evaluated in the same way as Table 2 shows the results. The gloss is
Each recording sheet showed high gloss at 60 to 65%.

[0082]

[Table 2] ────────────────────────────── Recording sheet Film surface pH Ink absorbency Water resistance Storage resistance Light resistance Resistance Curve property 10 4.0 ○ ○ 95 99 11 4.5 ○ ○ 95 97 125 .5 ○ △ 96 92 13 6.5 ○ × 98 81 14 4.0 ○ △ 82 85 ──────────────────────────── ──

[0083]

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

Claims (3)

[Claims] 1. An ink jet recording material having a porous ink receiving layer containing fumed silica fine particles on a support, wherein the ink receiving layer contains a cationic compound and a thiourea compound, An inkjet recording material having a pH of 3 to 6. 2. The ink jet recording material according to claim 1, wherein the ink receiving layer is crosslinked with a crosslinking agent. 3. The ink jet recording material according to claim 1, wherein the support is a water-resistant support.