JP2003191598A - Method for forming image on ink jet recording material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for forming an image on an ink jet recording material having high ink absorbability and glossiness and especially forming a printing image excellent in light fastness, indoor fading resistance, water resistance and image blur resistance with the elapse of time. <P>SOLUTION: In the method for forming an image on the ink jet recording material, a solvent absorbing layer capable of absorbing a solvent in water soluble dye ink is provided on a water-resistant support, and a fixing layer capable of holding a water soluble dye is provided on the solvent absorbing layer. After an image is formed on an ink receiving layer, a transparent resin protective layer is provided on the image formed surface of the ink receiving layer. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method for an ink jet recording material, and more specifically, it has high ink absorbency and glossiness, and also has light resistance of printed images, fading in a room, water resistance, and bleeding with time. The present invention relates to a method for forming an image on an ink jet recording material having good quality.

[0002]

2. Description of the Related Art As a recording material used in an ink jet recording system, a swellable ink receiving layer composed of a solvent swellable binder such as water on a support called an ordinary paper or an ink jet recording sheet, or an amorphous material. There is known a recording material provided with a porous ink receiving layer comprising a pigment such as silica and a water-soluble binder such as polyvinyl alcohol.

As an ink jet recording material provided with a porous recording layer, for example, JP-A-55-51583,
56-157, 57-107879, 57-
107880, 59-230787, 62-1
No. 60277, No. 62-184879, No. 62-18
As disclosed in JP-A No. 3382 and JP-A No. 64-11877, a recording material obtained by applying a silicon-containing pigment such as silica to a paper support together with an aqueous binder is proposed.

Further, Japanese Patent Publication No. 3-56552 and Japanese Patent Laid-Open No. Hei 2
-188287, 10-81064, 10
-119423, 10-175365, 10
-203006, 10-217601, 11
-20300, Doppei 11-20306, Doppei 11-
Japanese Patent No. 344881 and the like disclose recording materials using synthetic silica fine particles by a vapor phase method (hereinafter referred to as vapor phase method silica).

Further, JP-A-62-174183, JP-A-2-276670, JP-A-5-32037 and JP-A-6-199034 disclose recording materials using alumina or alumina hydrate. ing.

On the other hand, conventionally, paper has been generally used as a support for the ink jet recording material, and the paper itself has a role as an ink absorbing layer. In recent years, as photo-like recording sheets have been demanded, recording materials using a paper support have problems such as gloss, texture, water resistance, and cockling (wrinkles or corrugations) after printing. For example, resin-laminated paper (polyolefin resin-coated paper) in which a polyolefin resin such as polyethylene is laminated on both sides of paper, a plastic film, and the like have come to be used. However, when a water-resistant support is used as compared with a paper support, when printing with a water-soluble dye, the printed image is easily deteriorated by light, ozone in the air, trace gases such as nitrogen dioxide, and The above problems became remarkable when fine particles were used in the receiving layer. Further, there is a problem that the image is blurred due to contact with water.

Japanese Unexamined Patent Publication (Kokai) No. 8-118784 proposes a protective coating material containing an ultraviolet absorber which improves the light resistance of a printed image by applying it on the printed image, and Japanese Patent Laid-Open No. 8-17
Japanese Patent No. 4989 discloses a proposal for improving glossiness and water resistance of a printed image by thermally transferring an overcoat resin layer to the printed image.
Proposal to improve glossiness and water resistance by forming a top coat layer by jetting a top coat liquid of an aqueous resin emulsion on a printed image surface by an ink jet recording system. JP-A 2001-213044 discloses a recording material. It has been proposed that after the image formation, a protective layer having a specific oxygen transmission ratio with respect to the support is provided to improve glossiness, indoor fading (image deterioration due to a trace amount of gas), light resistance and the like.

Japanese Unexamined Patent Publication Nos. 5-16517 and 5
Japanese Patent Laid-Open No. 50739 proposes a recording material provided with a solvent-absorbent resin such as polyvinyl alcohol or gelatin.

As described above, many techniques relating to ink jet recording materials have been proposed, but they have not simultaneously satisfied light fastness, indoor color fastness, water fastness, and image bleeding over time.

[0010]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an ink jet recording material having high ink absorbency and gloss, and particularly light resistance of a printed image with water-soluble dye ink, indoor fading and water resistance. Another object of the present invention is to provide an image forming method of an inkjet recording material which is excellent in image bleeding property over time.

[0011]

The above object of the present invention is to provide a solvent-absorbing layer capable of absorbing a solvent in a water-soluble dye ink on a water-resistant support and to retain the water-soluble dye thereon. This is achieved by an image forming method for an ink jet recording material, which comprises forming a transparent resin protective layer on the image forming surface after forming an image on the ink jet recording material having a fixing layer that can be used.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
In the inkjet recording material of the present invention, a solvent absorbing layer capable of absorbing a solvent in a water-soluble dye ink is provided on a support, and a fixing layer capable of retaining a dye is provided on the solvent absorbing layer. It is a recording material.

In the present invention, a dye is prepared by providing a solvent absorbing layer capable of absorbing the solvent in the ink in the lower layer and providing a fixing layer capable of retaining the dye on the solvent absorbing layer. It is held in the upper layer, and it is possible to avoid a decrease in density and a decrease in saturation. Further, by providing a solvent absorbing layer capable of absorbing the solvent in the lower layer, the solvent remaining in the fixing layer can be reduced to the minimum. Therefore, the movement of the water-soluble dye due to the diffusion of the solvent can be minimized, the water-soluble dye is stable over time, and an image without bleeding can be obtained even after the formation of the transparent resin protective layer. Further, by forming the transparent resin protective layer in a state where the water-soluble dye and the solvent are separated, an image having excellent light resistance can be obtained.

Further, when a transparent resin protective layer (hereinafter referred to as a protective layer) is provided in the presence of a solvent in the vicinity of the printing surface, an image is bleeding, the adhesiveness of the protective layer is lowered, and high smoothness is protected. There is a problem that a layer is hard to be formed. In recent years, a printer having a printing section and a laminating section has been proposed. When such a printer is used, since the time from printing to lamination is short, the above problem becomes remarkable when the solvent is laminated in the vicinity of the printing surface. Therefore, by providing the recording material having the constitution of the present invention and the transparent protective layer, light resistance, gas resistance, image bleeding, smoothness of the protective layer, and protective layer adhesiveness can be simultaneously satisfied.

In the present invention, the solvent absorbing layer is a layer that absorbs and retains the solvent in the ink. As the solvent in the ink, a mixture of water and a polyhydric alcohol or glycol ether is usually used. Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, 1,3-propanediol, 1,5-pentanediol, 1,2,6-hexanetriol, glycerin, and mixtures thereof. Is mentioned. Examples of the glycol ethers include ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, propylene glycol monobutyl ether, dipropylene glycol monobutyl ether, triethylene glycol monobutyl ether. Butyl ether and the like can be mentioned. These polyhydric alcohols and glycol ethers are contained in 5 to 3% of all solvents.
It is generally contained at 0% by mass.

The solvent absorbing layer is a porous layer which mainly contains inorganic fine particles and absorbs and holds the ink in the spaces between the inorganic fine particles in order to absorb the solvent as described above, or absorbs the solvent. It is a layer mainly containing a resin.
Here, containing the inorganic fine particles or the resin mainly means that the inorganic fine particles or the resin is contained in an amount of 50% by mass or more, preferably 60% by mass or more, based on the total solid content of the solvent absorption layer.

The inorganic fine particles have an average particle diameter of 1 μm.
The following fine particles are preferable. As such inorganic fine particles, inorganic fine particles such as silica, titanium and calcium carbonate are preferable. These inorganic fine particles, in order to provide the voids necessary to sufficiently absorb the solvent in the solvent absorption layer,
Preferably contains 3 g / m ² or more, a range of 5 to 20 g / m ² is preferred. Further, it is preferable that the polymer dinder, such as polyvinyl alcohol, used for maintaining the film forming property of the solvent absorption layer mainly containing the inorganic fine particles is contained in an amount of about 5 to 30% by mass based on the inorganic fine particles.

The resin used in the solvent absorbing layer preferably absorbs the solvent by swelling, and examples thereof include polyvinyl alcohol, gelatin, starch, polyamide, polyacrylamide, polyvinylpyrrolidone,
Polyethyleneimine, melamine resin, polyurethane, polyester, sodium polyacrylate, polyacrylonitrile, polyvinyl chloride, polyvinyl acetate, phenol resin, celluloses such as carboxymethyl cellulose and hydroxymethyl cellulose, and the like, particularly preferably polyvinylpyrrolidone , Celluloses, gelatin (particularly phthalated gelatin), starch, and combinations thereof. These resins are 3 g / m ²
It is preferably contained as described above, and more preferably in the range of 5 to ²⁰ g / m ² .

It is preferable that the solvent absorption layer does not contain a cationic compound described later. Even when it is contained, it is preferably less than 0.5 mass% with respect to the total solid content of the solvent absorption layer. The solvent absorption layer further includes a surfactant as described below,
A crosslinking agent or the like can be included.

Since the water-soluble dye is anionic, the fixing layer of the present invention is preferably a layer having a high cationization tendency. Therefore, when using anionic inorganic fine particles such as silica fine particles, it is necessary to make them cationic by using a cationic compound such as a cationic polymer or a polyvalent metal. When using cationic inorganic fine particles such as alumina particles, a cationic compound is not always required.

The fixing layer of the present invention is preferably a layer mainly containing inorganic fine particles. Here, containing the inorganic fine particles as a main component means containing the inorganic fine particles in an amount of 50% by mass or more, preferably 60 to 90% by mass, based on the total solid content of the fixing layer. As the inorganic fine particles used in the fixing layer, fine particles of silica, alumina or alumina hydrate are preferably used. Of these, vapor phase silica, alumina or alumina hydrate is particularly preferable. In order to develop high ink absorbency, it is necessary to increase the void volume, and therefore it is necessary to coat a relatively large amount of inorganic fine particles on the support, and the amount of hydrophilic binder increases the porosity. It is preferable to reduce the amount.

The above-mentioned inorganic ultrafine particles are contained in the fixing layer in an amount of 8 g /
It is preferably contained in an amount of m ² or more, more preferably in the range of 10 to 30 g / m ² . The amount of the hydrophilic binder is 5 to 40% by mass with respect to the inorganic fine particles (that is, the mass ratio (PB ratio) of the inorganic fine particles to the hydrophilic binder is 20 to 40% by mass).
2.5), preferably 10-35% by weight (ie PB
It is preferred that the ratio is from 10 to about 2.9). By reducing the ratio of the hydrophilic binder in this way,
Although the ink absorptivity is improved, the indoor fading property after printing is particularly likely to decrease, and the present invention greatly improves the indoor fading property.

Vapor phase 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 burning silicon tetrachloride with hydrogen and oxygen is generally known, but instead of silicon tetrachloride, silanes such as methyltrichlorosilane and trichlorosilane may be used alone or in the form of silicon tetrachloride. It can be used as a mixture with. Vapor phase silica is Aerosil from Japan Aerosil Co., Ltd., Q from Tokuyama Corporation
It is commercially available as S type and can be obtained.

The inorganic ultrafine particles used in the fixing layer are preferably the above-described vapor grown silica, alumina or alumina hydrate, and of these, the average primary particle size is preferably 30 nm or less. In particular, the average particle size of the primary particles is 3 to 20 nm and the specific surface area by the BET method is 200.
It is preferably m ² / g or more (preferably 250 to 500 m ² / g). The BET method referred to in the present invention is one of the methods for measuring the surface area of powder by the vapor phase adsorption method, and is a method for obtaining the total surface area of 1 g of a sample, that is, the specific surface area, from the adsorption isotherm. Nitrogen gas is often used as the adsorbed gas, and the most commonly used method is to measure the adsorbed amount from the change in pressure or volume of the adsorbed gas. The most prominent of the isotherms for multimolecular adsorption are Brunauer, Emmett,
It is a Teller's formula, which is called BET formula, and is widely used for determining the surface area. The surface area is obtained by determining the adsorption amount based on the BET formula and multiplying the area occupied by one adsorbed molecule on the surface.

The fixing layer of the present invention needs to be cationized as described above. When alumina or alumina hydrate is used as the inorganic fine particles in the fixing layer, the cationic compound is not always necessary, but may be contained. When silica fine particles are used in the fixing layer, it is preferable that the cationic compound is contained in a range of 0.5 to 10% by mass based on the total solid content of the fixing layer.

The cationic compound will be described below. The cationic compound used in the present invention is preferably a cationic polymer or a water-soluble polyvalent metal compound.

Cationic polymers include polyethyleneimine, polydiallylamine, polyallylamine, alkylamine polymers, and JP-A-59-20696 and 59-3.
No. 3176, No. 59-33177, No. 59-1550
No. 88, No. 60-11389, No. 60-49990.
No. 60-83882, No. 60-109894,
62-198493, 63-49478, 6
3-115780, 63-280681, JP-A-1-40371, 6-234268, 7-12.
Polymers having a primary to tertiary amino group and a quaternary ammonium base described in JP 5411, 10-193776, etc. are preferably used. The molecular weight of these cationic polymers is preferably 5,000 or more, more preferably 5,000 or more.
About 100 to 100,000 is preferable.

The water-soluble polyvalent metal compound is calcium,
Examples thereof include water-soluble salts of metals selected from 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 chloride. Dicopper, ammonium chloride copper (II) dihydrate, copper sulfate, cobalt chloride,
Cobalt thiocyanate, cobalt sulfate, nickel sulfate hexahydrate, nickel chloride hexahydrate, nickel acetate tetrahydrate, nickel ammonium ammonium hexahydrate, nickel amidosulfate 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 citrate tungsten, 12 tungstophosphate n Hydrate, 12 tungstosilicic acid 26 hydrate, molybdenum chloride, 12 molybdophosphoric acid n hydrate and the like can be mentioned.

In the present invention, a water-soluble aluminum compound or a water-soluble compound containing a group 4A element of the periodic table is particularly preferable. As the water-soluble aluminum compound, for example, as an inorganic salt, aluminum chloride or its hydrate, aluminum sulfate or its hydrate, 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 is represented by the following general formula 1, 2 or 3 and has, for example, [Al ₆ (OH) ₁₅ ] ³⁺ , [Al ₈ (OH) ₂₀ ] ⁴⁺ ,
It is a water-soluble polyaluminum hydroxide which stably contains basic and polymeric polynuclear condensed ions such as [Al ₁₃ (OH) ₃₄ ] ⁵⁺ and [Al ₂₁ (OH) ₆₀ ] ³⁺ . .

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

These are water treatment agents under the name of polyaluminum chloride (PAC) from Taki Chemical Co., Ltd., under the name of 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 easily available. In the present invention, these commercially available products can be used as they are,
Some have an inappropriately low pH, and in that case, the pH can be adjusted appropriately before use.

The water-soluble compound containing an element of Group 4A of the periodic table used in the present invention is not particularly limited as long as it is water-soluble, but a water-soluble compound containing titanium or zirconium is preferable.
For example, as the water-soluble compound containing titanium, titanium chloride,
Titanium sulfate is a water-soluble compound containing zirconium, zirconium acetate, zirconium chloride, zirconium oxychloride, zirconium hydroxychloride, zirconium nitrate, basic zirconium carbonate, zirconium hydroxide, zirconium carbonate ammonium, zirconium carbonate potassium, zirconium sulfate. , Zirconium fluoride compounds and the like are known. Some of these compounds have an inappropriately low pH, and in that case, the pH can be adjusted appropriately before use. In the present invention, the term "water-soluble" means that it dissolves in water at 1% by mass or more under normal temperature and pressure.

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 polyvalent metal together.

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

Among the polyvinyl alcohols, those partially or completely saponified with a saponification degree of 80% or more are particularly preferable. Those having an average degree of polymerization of 200 to 5000 are preferable.

As the cation-modified polyvinyl alcohol, for example, as described in JP-A No. 61-10483, primary to tertiary amino groups or quaternary ammonium groups are added to the main chain or side chain of polyvinyl alcohol. It is polyvinyl alcohol contained therein.

In the fixing layer, it is particularly preferable to use a hydrophilic binder together with a crosslinking agent (hardening agent) for the binder. Specific examples of the cross-linking 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, US Pat.
Reactive halogen-containing compounds as described in 288,775, divinyl sulfone, US Pat. No. 3,635,7.
Compounds having a reactive olefin as described in US Pat. No. 18, N-methylol compounds as described in US Pat. No. 2,732,316, isocyanates as described in US Pat. No. 3,103,437, US Pat. , 017, 280,
No. 2,983,611, aziridine compounds, US Pat. No. 3,100,704, carbodiimide compounds, US Pat. No. 3,091,537, epoxy compounds, mucochloric acid, etc. There are halogen carboxaldehydes, 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 preferable.

The amount of the cross-linking agent used varies depending on the kind of the hydrophilic binder, the kind of the cross-linking agent, the kind of the inorganic fine particles and the PB ratio, but is generally about 5 per 1 g of the hydrophilic binder.
The range is from ~ 600 mg, preferably from 10 to 500 mg.

The film surface pH of the fixing layer is preferably 3 to 6. The film surface pH is determined by J. TAPPI paper pulp test method N0.
Surface pH measured after 30 seconds with distilled water according to the method described in 49.

The fixing layer may contain various oil droplets in order to further improve the brittleness of the film. Such oil droplets include hydrophobic high-boiling point organic solvents having a solubility in water of 0.01% by mass or less at room temperature (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, hydroxyethyl methacrylate) can be contained. Such oil droplets can be preferably used in the range of 10 to 50% by mass with respect to the hydrophilic binder.

In the present invention, a surfactant can be added to the fixing layer and the solvent absorbing layer. The surfactant used may be any of anionic type, cationic type, nonionic type, betaine type, and low molecular weight type or high molecular weight type. One or more kinds of surfactants are added to the ink receiving layer coating liquid, but two or more kinds of surfactants can be used in combination. The amount of the surfactant added is 100 g of the binder constituting the ink receiving layer.
However, 0.001 to 5 g is preferable, and 0.01 to 3 g is more preferable.

In the present invention, the fixing layer and the solvent absorbing layer further include coloring dyes, coloring pigments, ink dye fixing agents, ultraviolet absorbers, antioxidants, pigment dispersants, defoaming agents, leveling agents, and antiseptics. It is also possible to add various known additives such as agents, optical brighteners and viscosity stabilizers.

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

The base paper constituting the resin-coated paper preferably used in the present invention is not particularly limited, and commonly used paper can be used, but more preferably, it is smooth as used for a photographic support. Raw base paper is preferred. As the pulp constituting the raw paper, one kind or a mixture of two or more kinds of natural pulp, recycled pulp, synthetic pulp and the like is used. This base paper has a sizing agent, a paper strengthening agent, a filler, an antistatic agent, an optical brightening agent, which is generally used in papermaking,
Additives such as dyes are blended. In addition, surface sizing agents,
A surface paper strength agent, a fluorescent whitening agent, an antistatic agent, a dye, an anchoring agent and the like may be applied on the surface.

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

As the resin for the resin-coated paper, a polyolefin resin or a resin curable with an electron beam can be used.
The polyolefin resin is a homopolymer of olefins such as low-density polyethylene, high-density polyethylene, polypropylene, polybutene, and polypentene, or a copolymer of two or more olefins such as ethylene-propylene copolymer and a mixture thereof. Various densities and melt viscosity indexes (melt indexes) 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 stearic acid amide and arachidic acid amide, zinc stearate, calcium stearate, stearic acid. 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, Phthalocyanine Blue, Cobalt Violet, Fast Violet, Manganese Purple It is preferable to add various additives such as magenta pigments and dyes, fluorescent whitening agents, and ultraviolet absorbers in an appropriate combination.

The resin-coated paper, which is a support preferably used in the present invention, is produced by a so-called extrusion coating method in which a resin melted by heating is cast in the case of a polyolefin resin on a running base paper, and both surfaces of the resin are coated. Is covered by. 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 the resin is irradiated with an electron beam to cure and coat the resin. Further, it is preferable to perform activation treatment such as corona discharge treatment or flame treatment on the base paper before coating the base paper with the resin. The surface (surface) of the support to which the ink receiving layer is applied has a glossy surface, a matte surface or the like depending on the application, and the glossy surface is particularly predominantly used. It is not necessary to coat the back surface with a resin, but it is preferable to coat the resin from the viewpoint of preventing curling. The back surface is usually a matte surface, and the front surface or both front and back surfaces can be subjected to activation treatment such as corona discharge treatment and flame treatment, if necessary. The thickness of the resin coating layer is not particularly limited, but it is generally coated on the surface or both front and back sides with a thickness of 5 to 50 μm.

Various back coat layers can be coated on the support in the present invention for the purpose of antistatic property, transport property, curl prevention property and the like. The back coat layer may 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.

The coating method in the present invention is not particularly limited, and a known coating method can be used. For example,
There are slide lip method, curtain method, extrusion method, air knife method, roll coating method, rod bar coating method and the like.

In the present invention, after printing on the above-mentioned ink jet recording material by the ink jet method, the transparent resin protective layer as described above, that is, the thermoplastic resin or the heat fusible film formed by heating, is formed on the image surface after printing. Resin, a method of forming a coating layer by coating various resin solutions such as a resin that cures by ultraviolet irradiation (for example, using a bar coater, roll coater, applicator, spinner or inkjet recording device), heat resistance of the overcoat resin layer A coating layer is provided by a method of thermal transfer through a film, or by laminating a laminated film on the recorded surface. The coating layer can be applied either before or after the recorded image is dried. After applying the coating layer, heat, wind, UV light, microwave,
Infrared rays or the like can be applied to the coating layer as needed.

Particularly, the light resistance is further improved by providing the transparent resin protective layer by a method in which the image forming surface is heated to 50 ° C. or higher. The solvent absorbing layer as the lower layer has high solvent absorbency, and the coloring layer and the solvent in the ink are easily separated by the fixing layer as the upper layer, so that the light resistance is improved, and the provision of the transparent resin protective layer provides good indoor fading. In particular, when a transparent resin protective layer is provided, the temperature of the image forming surface is 50 ° C. or higher, preferably 65 ° C. or higher. It is presumed that the light resistance is improved because the colorant and the solvent are easily separated from each other by permeating and diffusing into the layer and the colorant has a high light stability. There is no particular upper limit to the heating temperature of the image forming surface in the case of providing the transparent resin protective layer, but if it is too high, the support may be softened or the colorant or the like may be deteriorated. It is 200 ° C or lower. Although the time for heating the image forming surface is related to the temperature for heating, it is generally 0.1 seconds or longer, preferably 0.5 seconds or longer.
There is no particular upper limit, but there is no difference in effect even if heated for 30 seconds or longer.

In the present invention, another preferable method for forming the transparent resin protective layer is to bond a transparent laminate film to the image surface, which may or may not be heated at the time of bonding. Is preferably heated to 50 ° C. or higher. As the laminate film, a transparent base material coated with an adhesive or an adhesive is preferably used. Examples of the transparent substrate include various films such as polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyphenylene sulfite, polyether sulfone and polyvinyl chloride. The thickness of the transparent substrate is generally 20 to 200 μm, preferably about 30 to 100 μm. These base materials include benzophenones such as 2-hydroxybenzophenone and 2,4-dihydroxybenzophenone, and ultraviolet absorbers such as (2-hydroxyphenyl) benzotriazole and (2-hydroxyphenyl-5-methylphenyl) benzotriazole. May be included.

A heat-sealing type or pressure-sensitive adhesive type resin is publicly used as the pressure-sensitive adhesive or adhesive. As the resin, any of styrene type, butadiene type, acrylic type, urethane type and the like can be used, but acrylic adhesives are preferable, for example, methyl methacrylate, ethyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, Acrylic monomers such as N-methylolacrylamine and copolymers such as ethylene-based monomers and styrene-based monomers copolymerizable therewith can be used.

[0056]

The present invention will be described in detail below with reference to typical examples. In addition, a part means a solid content mass part.

Example 1 A 1: 1 mixture of bleached hardwood kraft pulp (LBKP) and bleached softwood sulfite (NBSP) was beaten to 300 ml with Canadian Standard Freeness to prepare a pulp slurry. Alkyl ketene dimer as a sizing agent to 0.5% by mass of pulp,
1.0% by mass of polyacrylamide to the pulp, 2.0% by mass of cationized starch to the pulp, and 0.5% by mass of polyamide epichlorohydrin resin to the pulp as a strengthening agent, and diluted with water to 1%. It was made into a slurry. This slurry was made into paper by a Fourdrinier paper machine so as to have a basis weight of 170 g / m ² , dried and conditioned to obtain a base paper for polyolefin resin-coated paper. A polyethylene resin composition, in which 10% by mass of anatase-type titanium was uniformly dispersed in 100% by mass of a low-density polyethylene resin having a density of 0.918 g / cm ³ , was melted at 320 ° C. in a paper-making base paper, and 200 m / 35 μm in thickness
Extrusion coating was carried out so as to be, and extrusion coating was carried out using a cooling roller having a finely roughened surface. On the other surface, 70 parts by mass of a high density polyethylene resin having a density of 0.962 g / cm ³ and 30 parts by mass of a low density polyethylene resin having a density of 0.918 were similarly melted at 320 ° C. to obtain a thickness of Extrusion coating to 30 μm,
It was extrusion coated using a roughened cooling roll.

After the high-frequency corona discharge treatment was applied to the surface of the polyolefin resin-coated paper, the undercoat layer was coated with gelatin.
A support was prepared by coating and drying so as to give 0 mg / m ² .

<Preparation of Inkjet Recording Material 1> Polyvinylpyrrolidone 3 g / m ² and phthalated gelatin 3 g /
A solvent absorbing layer consisting of m ² is applied on the support, dried,
Furthermore, a fixing layer having the following composition is further coated with 15% of fumed silica.
It was applied and dried so as to be g / m ² .

<Fixing layer> Vapor phase method silica (average primary particle size 7 nm, specific surface area by BET method 300 m ² / g) 100 parts Dimethyldiallylammonium chloride polycondensate 3 parts (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., product Name Charol DC902P) Polyvinyl alcohol 25 parts (Product name: PVA235, manufactured by Kuraray Co., Ltd., saponification degree 88%, average degree of polymerization 3500) Basic polyaluminum hydroxide (Purachem WT manufactured by Riken Green Co., Ltd.) 3 parts Boric acid 4 Part Amphoteric surfactant 0.3 part (Product name: SWAM AM-2150, made by Nippon Surfactant)

<Inkjet recording material 2> The inkjet recording material 2 was prepared in the same manner as the inkjet recording material 1. However, it was changed to a layer made of a solvent-absorbing layer from hydroxymethylcellulose 3 g / m ² and polyvinyl pyrrolidone 3 g / m ^2.

<Inkjet recording material 3> Inkjet recording material 1 was prepared in the same manner. However, the solvent absorption layer was changed as follows, and the fumed silica was coated so as to have a concentration of 8 g / m ² . <Solvent absorption layer> Vapor phase silica (average primary particle size 12 nm, specific surface area by BET method 200 m ² / g) 100 parts Polyvinyl alcohol 25 parts (PVA235, Kuraray Co., saponification degree 88%, Average degree of polymerization 3500) Boric acid 4 parts Amphoteric surfactant 0.3 parts (Product name: SWAM AM-2150, manufactured by Nippon Surfactant)

<Production of Inkjet Recording Material 4> Inkjet recording material 1 was produced in the same manner. However, the fixing layer was changed to the following and coated so that the alumina hydrate had a content of 15 g / m ² . <Fixing layer> Alumina hydrate 100 parts (tabular particles having an average primary particle size of 14 nm and an aspect ratio of 5) Nitric acid 1 part Cationic polymer 4 parts (polycondensate of dimethylamine and epichlorohedrin) Jet Fix 30 manufactured by Satoda Kako Co., Ltd. ) Boric acid 0.5 parts Polyvinyl alcohol 15 parts (Saponification degree 88%, average degree of polymerization 3500) Surfactant 0.5 parts

<Production of Inkjet Recording Material 5> Inkjet recording material 4 was produced in the same manner. However, the solvent absorption layer was replaced with the solvent absorption layer of the inkjet recording material 3.

<Inkjet recording material 6> Inkjet recording material 6 was prepared in the same manner as in the inkjet recording material 1. However, no solvent absorption layer was provided.

<Production of Inkjet Recording Material 7> Inkjet recording material 7 was produced in the same manner. However, no solvent absorption layer was provided.

Two pieces of each of the seven kinds of ink jet recording materials prepared as described above were prepared, and an ink jet printer (PM-800 manufactured by Seiko Epson Corporation) was prepared.
C) was used to print images of C, M, and Y at 100%. One of the two sheets is a laminated film (50 μm thick film having an adhesive layer: LA with a recording material after printing).
Product made by MI CORPORATION; LAMINATIN
A recording sheet is sandwiched between G FILM) and a laminator (NAKABAYASHI Co. Ltd .; PACL
AMI PRO; Model PLP-325) was used to bond at a heating temperature of 125 ° C. to prepare a recording sheet 1B.

Recording materials 2 to 7 were prepared in the same manner as in 1B above.
2B to 7B were produced by using.

Each of the obtained ink jet recording sheets was evaluated as follows. The results are shown in Table 1.

<Ink Absorption> Using an inkjet printer (PM-800C manufactured by Seiko Epson Corporation),
C, M, and Y were printed at 100% respectively, and immediately after printing, PPC paper was overlaid on the printing part and lightly pressed, and the amount of ink transferred to PPC paper was visually observed and evaluated according to the following criteria. . ◯: No transfer is performed. Δ: Transfer a little. X: Transfers considerably.

<Bleeding property over time> 10 fine lines with a width of 100 μm
Print at 0 μm intervals, leave for 1 day, then 23 ° C 50%
After standing for 10 days under the condition of relative humidity (RH), blurring of fine lines was evaluated according to the following criteria. ◯: Almost no blurring, and the interval between fine lines is clear. Δ: There is bleeding, but the space between the thin lines is not completely crushed. X: Fine lines are blurred and there is no space between the fine lines.

<Adhesiveness of Laminate Layer> After forming a printed image, a laminating process was performed by the above method, and the degree of adhesion between the laminating layer and the fixing layer was visually observed and evaluated according to the following criteria. ◯: No peeling at all. Δ: A little peeled off. X: Exfoliated considerably.

<Light resistance> Using an ink jet printer (PM-770C manufactured by Seiko Epson Corporation), CYMK
After solid printing with each ink, and irradiating at 600 W / m ² with Suntest CPS photobleaching tester manufactured by Atlas Co., Ltd. for 30 hours, the density of the printed part was measured, and the image residual ratio (concentration after irradiation / before irradiation Of the CMYK images, and the one with the lowest residual rate was displayed.

<Indoor Fading Property> After printing as in the light resistance test, after exposure in air at room temperature for 2 months, the density of the printed part was measured, and the image residual ratio (concentration after exposure / concentration before exposure) )
Of the CMYK images, the one with the lowest residual rate was displayed.

[0075]

[Table 1] ──────────────────────────────────── Recording sheet Ink absorption Absorption over time Storage stability (%) Laminate layer adhesion Remarks                                   Light resistance Indoor fading ────────────────────────────────────   1 ○ △ 74 70-Comparative example   2 ○ △ 76 69-Comparative example   3 ○ △ 76 70-Comparative example   4 ○ △ 75 72 ― Comparative example   5 ○ △ 76 72 ― Comparative example   6 ○ △ 71 67 ― Comparative example   7 ○ △ 70 69-Comparative example   1B ○ ○ 84 99 ○ The present invention   2B ○ ○ 85 99 ○ The present invention   3B ○ ○ 86 99 ○ The present invention   4B ○ ○ 85 99 ○ The present invention   5B ○ ○ 85 99 ○ The present invention   6B ○ △ 73 99 × Comparative example   7B ○ △ 72 99 × Comparative example ────────────────────────────────────

As is clear from the above results, the use of a laminate film or the provision of a solvent absorption layer improves the storage stability. However, the use of a laminate film alone causes marked fading in the room. Although it is improved, bleeding with time and light resistance are insufficient. Further, if the laminated film is formed immediately after printing, there is a problem that the adhesiveness of the laminated film is poor. Next, providing a solvent absorption layer improves the light resistance, but is still insufficient,
Almost no improvement in indoor fading.

By providing the solvent absorbing layer of the present invention and further providing the laminate film after printing, a recording sheet having good indoor fading properties, light resistance, and bleeding with time was obtained. Further, even when the laminated film is used immediately after printing, the adhesive property of the laminated film is good by providing the solvent absorbing layer.

When the layer mainly containing a resin such as polyvinylpyrrolidone or hydroxymethyl cellulose is used as the solvent absorbing layer, or when the layer mainly containing the inorganic fine particles such as silica is used, the solvent absorption layer is the same. Showed the effect.

As the fixing layer, the same results were shown in the case of using vapor grown silica and the case of using alumina.

[0080]

According to the present invention, it is possible to obtain a photo-like ink jet recorded material having high ink absorbency, high water resistance, high gloss, and dramatically superior light resistance and gas resistance.

Claims (6)

[Claims] 1. An ink jet having a solvent absorbing layer capable of absorbing a solvent in a water-soluble dye ink on a water-resistant support, and a fixing layer capable of retaining the water-soluble dye thereon. An image forming method for an inkjet recording material, which comprises forming a transparent resin protective layer on the image forming surface after forming an image on the recording material. 2. The transparent resin protective layer is provided after the image formation by a method in which the image formation surface is heated to 50 ° C. or higher.
The method for forming an image on the inkjet recording material according to 1. 3. The image forming method for an inkjet recording material according to claim 1, wherein the transparent resin protective layer is a laminated film, and the laminated film covers the image surface and the cut surface of the recording material. 4. The fixing layer comprises vapor grown silica, alumina,
Alternatively, the image forming method of the inkjet recording material according to any one of claims 1 to 3, which mainly contains an alumina hydrate and further contains a cationic compound. 5. The solvent absorbing layer according to claim 1, wherein the solvent absorbing layer is a layer mainly containing a resin that absorbs the solvent in the ink receiving layer, or a layer mainly containing inorganic fine particles. An image forming method for an inkjet recording material. 6. The method for forming an image on an inkjet recording material according to claim 1, wherein the water resistant support is a polyolefin resin-coated paper having at least one surface coated with a polyolefin resin.