JP2001287450A - Ink jet recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording material suitable for ink jet recording and especially excellent in heat resistance, humidity resistance, blocking resistance, scratch resistance, slip properties, printing quality or the like. SOLUTION: The ink jet recording material is constituted by providing an ink absorbing layer based on a water absorbable resin and a heat-resistant layer being the outermost layer on a substrate. As the water absorbable resin, for example, polyalkylene oxide, a water soluble polyester resin, a water soluble polyurethane resin, a cellulosic compound and modified matters of them are preferably used.

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 suitable for ink jet recording, and more particularly to an ink jet recording material excellent in heat resistance, blocking resistance, scratch resistance, slipping property, printing quality and the like. .

[0002]

2. Description of the Related Art Recording by the ink jet method has no noise, enables high-speed printing, and is inexpensive. Therefore, it is used in image information output devices such as color copiers and computers, and is rapidly spreading. As an inkjet recording material, a material using a hydrophilic resin such as polyvinyl alcohol (PVA) or polyvinyl pyrrolidone or a thermoplastic resin of polyethylene oxide is known. An ink jet recording material in which PVA or the like is applied on a substrate has a reduced ink receiving layer, and thus has a low ink absorption capacity, causes a decrease in a drying speed, and the like. There was a problem with print quality. Also,
In a high temperature environment, stickiness was caused by bleed-out of contained components, and there was also a risk of blocking. An ink jet recording material formed using a polyethylene oxide-based thermoplastic resin has a low melting point due to the physical properties of the resin, and thus has a problem that blocking occurs in a high-temperature and high-humidity environment.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to improve heat resistance, blocking resistance, scratch resistance, slippage and printing quality. An object of the present invention is to provide an ink jet recording material.

[0004]

The ink-jet recording material of the present invention is characterized in that it has an ink-adsorbing layer mainly composed of a water-absorbing resin and a heat-resistant layer as the outermost layer on a substrate. Here, the water-absorbing resin is a resin composition containing at least one selected from the group consisting of polyalkylene oxides, water-soluble polyester resins, water-soluble polyurethane resins, cellulose compounds, and modified products thereof. Can be. Further, the water absorbent resin,
The following general formula (1)

Embedded image Where a, b and c are each an integer of 1 or more, and a weight ratio calculated from a, b and c, 44 (a + c)
/ (Molecular weight of α-olefin oxide having 3 or more carbon atoms)
b, is 80/20 to 94/6, X ₁ is a residue of an organic compound having two active hydrogen groups, Z is a hydrocarbon group having 1 or more carbon atoms, R ₁₁ is a residue of a dicarboxylic acid compound or diisocyanate. Which is a system compound residue). Further, the heat-resistant layer can be made of a resin composition containing a polyvinyl alcohol-based resin or a urethane-based resin as a main component.

The heat-resistant layer can be composed of a composition containing a polyurethane resin emulsion having an alkylene oxide chain in the molecule and having an average particle size of 3.0 μm or less. Further, the heat-resistant layer comprises (A) an aqueous dispersion of a polyolefin having a carboxylic acid group in the molecule, (B) ethylene, and α, β- having an acid group partially neutralized with a basic compound. It can be composed of a composition containing an aqueous dispersion of a copolymer with an ethylenically unsaturated carboxylic acid and (C) an aqueous dispersion of a polyurethane resin having a sulfonic acid group.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The ink jet recording material of the present invention has an ink absorbing layer and a heat resistant layer on a substrate. The heat-resistant layer constitutes the outermost layer of the inkjet recording material, and the ink-adsorbing layer is located between the substrate and the heat-resistant layer. Further, another layer may be provided between the ink absorbing layer and the substrate. The ink-adsorbing layer is made of a resin composition containing a water-absorbing resin as a main component, the heat-resistant layer is made of a resin composition that protects the ink-adsorbing layer from heat, and the other optional layer is, for example, a hydrophilic resin layer. In such a case, a general-purpose hydrophilic resin can be contained.

The heat-resistant layer is preferably made of a resin composition containing a water-soluble resin as a main component. Examples of the water-soluble resin include polyvinyl alcohol-based resins such as polyvinyl alcohol (hereinafter sometimes referred to as “PVA”) and modified polyvinyl alcohol. And urethane-based resins are preferably used.
Specific examples include fully saponified polyvinyl alcohol, partially saponified polyvinyl alcohol, cation-modified polyvinyl alcohol, polyvinyl acetal, polyvinyl alcohol copolymerized with other resins, and polyvinyl alcohol blended with other hydrophilic polymers. The water-soluble resin used in the present invention preferably has a melting point of 80 ° C. or more, and preferably has a hydrophilic group, for example, —OH or —COOH in a structural unit of the resin.

The polyvinyl alcohol (PVA) used for forming the heat-resistant layer is not particularly limited, and includes those generally used. For example, cold water-soluble PVA, preferably having a saponification degree of 20-1
It is preferably 00%, more preferably 20 to 90%, particularly preferably 40 to 80%. Decomposition temperature and melting point (molding temperature)
Is preferably 20 ° C. or more. In order to make the temperature difference between the decomposition temperature and the melting point (Tm) 20 ° C. or more,
For example, the viscosity average degree of polymerization of PVA is 200 to 1,000.
Or by forming a copolymer of PVA and an ethylenic monomer, or
, A temperature difference can be increased to 20 ° C or more. When a temperature difference is set by forming a copolymer of PVA and an ethylenic monomer, for example, N-vinylpyrrolidone may be polymerized at about 10 mol%. When the temperature difference is set by adding a plasticizer, it is preferable to add glycerin, ethylene glycol, or the like at about 15% by weight. In this way, the melting point of PVA can be set to 180 ° C. or less, and thus the temperature difference between the decomposition temperature and the melting point can be set to 20 ° C. or more.

The viscosity average polymerization degree of the PVA used in the present invention is preferably from 40 to 5,000, more preferably from 50 to 2,000, particularly preferably from 100 to 1,000. The PVA used in the present invention has a weight average molecular weight (Mw) and a number average molecular weight (Mn) in order to improve necking (a film or a sheet extruded from an extruder is shrunk in a transverse direction and bent). Ratio (M
(w / Mn) is preferably 2.8 or more.

Examples of the urethane resin used for the heat-resistant layer include a polyurethane resin containing an alkylene oxide chain, a polyurethane resin containing a sulfonic acid group, a polyurethane resin containing a polycarbonate chain, and a polyurethane resin containing a polycarbonate chain and a polyester chain. And the like, for example, the trade name "Paterachor A-
60 "(Dainippon Ink Co., Ltd.) can be commercially obtained.

The heat-resistant layer in the present invention can be composed of a composition containing a polyurethane resin emulsion having an average particle having an alkylene oxide chain in a molecule of not more than 3.0 μm. Here, examples of the alkylene oxide chain include ethylene oxide, propylene oxide, butylene oxide, and the like, or a combination thereof. The polyurethane resin is preferably produced by reacting a polyol having an alkylene oxide chain with an aliphatic isocyanate compound.

The heat-resistant layer in the present invention comprises: (A) an aqueous dispersion of a polyolefin having a carboxylic acid group in the molecule;
(B) an aqueous dispersion of a copolymer of ethylene and an α, β-ethylenically unsaturated carboxylic acid having an acid group partially neutralized with a basic compound, and (C) a sulfonic acid group And an aqueous dispersion of a polyurethane resin. The polyolefin constituting the aqueous dispersion of (A) is preferably an ethylene polymer.
The α, β-ethylenically unsaturated carboxylic acid having an acid group partially neutralized with a basic compound, which constitutes the aqueous dispersion of (B), comprises 20 to 75% of the carboxylic acid group as a basic compound. It is preferably neutralized with. The polyurethane resin having a sulfonic acid group constituting the aqueous dispersion of (C) includes:
It is preferable that the dried film does not dissolve in tetrahydrofuran (THF). Further, the basic compound is preferably an alkali metal salt. In the present invention, the aqueous dispersion of (A), the aqueous dispersion of (B), and the aqueous dispersion of (C) are converted to a solid content of {(A) + (B)} / (C) = 80 /
It is preferable to mix within a range satisfying 20 to 20/80.

The heat-resistant layer preferably further contains a water-soluble epoxy compound and / or acetoacetylated vinyl alcohol and / or epichlorohydrin polyamide resin.

Examples of the water-absorbing resin used in the ink-adsorbing layer include thermoplastic resins. Examples thereof include polyalkylene oxide, water-soluble polyester resin, water-soluble polyurethane resin, cellulose compound, and modified products thereof. Is mentioned. These may be used alone or in combination of one or more.

The water-absorbing resin used in the present invention has a water absorption of 10 times or more its own weight, and has an organic carbon content eluted from the water-absorbing resin of 0.1 when immersed in water at 25 ° C. for 30 minutes. % Is preferable.

In the present invention, a hydrophilic thermoplastic resin composed of a repeating unit represented by the following general formula (1) is preferably used for the ink-adsorbing layer.

Embedded image Where a, b and c are each an integer of 1 or more, and a weight ratio calculated from a, b and c, 44 (a + c)
/ (Molecular weight of α-olefin oxide having 3 or more carbon atoms)
b, is 80/20 to 94/6, X ₁ is a residue of an organic compound having two active hydrogen groups, Z is a hydrocarbon group having 1 or more carbon atoms, R ₁₁ is a residue of a dicarboxylic acid compound or diisocyanate. This is a system compound residue. Where a, b,
weight ratio calculated from c, 44 (a + c) / (carbon number 4
The molecular weight b) of the above α-alkylene oxide is 80 /
It is preferable that c / (a + c) is 50% by weight or more, and Z is a hydrocarbon group having 2 or more carbon atoms.

Examples of the organic compound having two active hydrogen groups include ethylene glycol, propylene glycol, bisphenol A, aniline propylene glycol, and polytetramethylene glycol.

The weight ratio described above, that is, 44 (a + c)
/ (Molecular weight of α-olefin oxide having 3 or more carbon atoms)
If b is less than 80/20, the hydrophilicity is reduced, and the ink absorbency and printability are poor. On the other hand, when the ratio exceeds 94/6, the ink becomes poor in bleeding water resistance and the like. Z has a function of imparting hydrophobicity to the resin composition represented by the general formula (1), and preferred examples include an alkyl group such as an ethyl group.
By setting the proportions of a, b, and c within the above ranges, hydrophilicity can be maintained and water can be insolubilized. Such a thermoplastic resin may be formed by addition polymerization of ethylene glycol to ethylene glycol, then addition polymerization of an alkylene oxide, and reaction of a dicarboxylic acid compound or a diisocyanate compound with a polyalkylene oxide formed by addition polymerization of ethylene oxide. it can.

The dicarboxylic acid compound is preferably a cyclic dicarboxylic acid compound or a linear dicarboxylic acid compound, and examples thereof include dicarboxylic acids, dicarboxylic anhydrides, and lower alkyl esters of dicarboxylic acids. Examples of the dicarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, malonic acid, succinic acid, sebacic acid, maleic acid, fumaric acid, adipic acid, and itaconic acid. Examples of the dicarboxylic anhydride include anhydrides of the above-mentioned various dicarboxylic acids. Examples of the lower alkyl esters of the above dicarboxylic acids include methyl esters, dimethyl esters, ethyl esters, diethyl esters, propyl esters, dipropyl esters and the like of the above various dicarboxylic acids. Particularly preferred are linear dicarboxylic acids having 12 to 36 carbon atoms and lower alkyl esters thereof, and 1,10-decamethylene dicarboxylic acid,
Examples thereof include 14-tetradecamethylene dicarboxylic acid, 1,18-octadecamethylene dicarboxylic acid, and 1,32-dotriacontamethylene dicarboxylic acid. Examples of the lower alkyl ester include methyl, ethyl, and propyl esters of these dicarboxylic acids.
Dipropyl ester and the like. These alone,
Alternatively, two or more kinds can be used in combination. Among them, it is preferable to use the above-mentioned dicarboxylic anhydride and lower alkyl ester of dicarboxylic acid from the viewpoint of ease of reaction.

The diisocyanate compound includes
4,4'-diphenylmethane diisocyanate, toluene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, methylene biscyclohexyl diisocyanate, and the like. These alone,
Alternatively, two or more kinds can be used in combination.

The ink jet recording material of the present invention may contain a cationic polymer for the purpose of improving the bleeding characteristics of the ink. The layer to which the cationic polymer is added is not particularly limited. For example, the layer can be contained in one or both of the ink absorbing layer and the heat-resistant layer. As the cationic polymer preferably used in the present invention, for example, polyallylamine hydrochloride,
Polymer compounds such as copolymers composed of monomers having a quaternized amino group, such as polyalkylaminoacrylates, may be mentioned. These polymers have melting points (T
m) is in the range of 60 ° C to 200 ° C and the molecular weight is 1,0.
It is preferable to be in the range of from 100,000 to 100,000.

In the present invention, the content of the cationic polymer is preferably about 5 to 70% by weight. When the content of the cationic polymer is 5% by weight or more, bleeding of the ink can be effectively suppressed.

The ink adsorbing layer, the heat-resistant layer and the like may further contain a cationic activator or a nonionic activator. In the present invention, the content of the cationic activator or the nonionic activator in the resin is preferably in the range of 1% by weight to 10% by weight. Cationic activators preferably used in the present invention include polyethyleneimine, quaternary ammonium chloride, quaternary ammonium sulfate, and the like. Nonionic activators preferably used in the present invention include polyoxyethylene alkylamine And glycerin fatty acid esters.

The resin composition for forming the ink adsorbing layer and the resin composition for forming the heat-resistant layer are blended and then mixed using a twin-screw extruder, preferably using a co-directional twin-screw extruder. After that, it can be pelletized. Preferably, pelletization is performed at a temperature of about 160 ° C.

In the present invention, various additives such as an antioxidant and an ultraviolet inhibitor can be further contained as long as the properties of the present invention are not impaired. For example, an antioxidant can be included in the resin composition in order to prevent thermal deterioration during melt extrusion. In addition, the amount of the antioxidant added for improving the thermal stability is 0.3 to 1.5.
A suitable amount is about weight%.

Further, a plasticizer or the like can be included in order to improve the texture of the material, such as the feel and softness of the ink jet recording material. Examples of the plasticizer preferably used in the present invention include polyethylene glycol (PEG). In addition, a filler can be included to prevent blocking. Examples of the filler preferably used in the present invention include an inorganic filler such as talc.

The ink-jet recording material of the present invention has a substrate, and an ink-adsorbing layer and a heat-resistant layer on the substrate. As a method for laminating the ink jet recording material of the present invention, for example, a co-extrusion method in which the resin composition of each layer is co-extruded and laminated, two or more layers are formed into a film by co-extrusion, and this is laminated with another sheet. It can be manufactured by an extrusion lamination method or the like. For example, the resin composition of each of the substrate, the ink-adsorbing layer and the heat-resistant layer is individually compounded or, if necessary, formed into pellets, which are put into the respective hoppers of a three-layer T-die extruder in which T-dies are covalently connected. For example, it can be melted at a temperature in the range of 100 to 170 ° C., co-extruded from a three-layer T-die, and solidified by cooling with a cooling roll, water or air cooling to form a three-layer laminate ink jet recording material. . Alternatively, the resin composition of each layer of the ink absorbing layer and the heat-resistant layer is melted by being mounted on a two-layer T-die extruder.
An ink jet recording material can also be produced by extruding directly from the layer T die onto the substrate. After forming a laminated film by two-layer co-extrusion, the laminated film may be laminated on a substrate, or may be laminated on a substrate via an adhesive. When PVA is used as the resin for forming the heat-resistant layer, a laminate of the ink-adsorbing layer and the heat-resistant layer is formed by appropriately selecting the degree of polymerization and the degree of saponification of PVA and extruding the same. Is preferred. In the present invention, the layers on the substrate are not limited to the ink-adsorbing layer and the heat-resistant layer. Therefore, when three or more layers are provided on the substrate, the number of T
It can be similarly prepared using a T-die extruder equipped with a die. When one or more layers are provided between the ink absorbing layer and the substrate, for example, a sheet provided with such a layer is formed on the substrate, while the ink absorbing layer and the heat-resistant layer are used together. It can also be provided by extruding and laminating them.

In the present invention, the heat-resistant layer may be formed by coating or the like. For example, it can be formed by applying a solution obtained by dissolving a resin composition for forming a heat-resistant layer in a solvent such as water on the ink absorbing layer with a bar coater, a gravure coater or the like. Alternatively, it may be formed by applying the above solution on a temporary support to form a film, and then transferring this film onto the ink absorbing layer.

Such an ink jet recording material can be formed by a known method.
No. 71763, pages (6) to (7). Various substrates such as plastic and paper can be used as the substrate depending on the application. For example, a transparent substrate is selected as an inkjet recording material used for an overhead projector or the like.

The ink-jet recording material has the following features by adopting a structure in which the outermost heat-resistant layer has a water-soluble resin and the ink-adsorbing layer immediately below the outermost layer has a water-absorbent resin. be able to. Although it has a strong hydrophilic part in the molecule, it introduces a hydrophobic group into the molecular structure, performs processing such as electron beam and γ-ray, and creates a crosslinking point by adding a crosslinking agent. By doing so, the water-absorbent resin, which suppresses the hydrophilic portion from being dissolved in water, has a slightly lower reaction rate with respect to water than the water-soluble resin because the movement of molecules is suppressed. Since the outermost layer has a layer made of a water-soluble resin, the ink is immediately absorbed by the water-soluble resin when the ink lands, and the ink-absorbing layer is provided immediately below that layer. Completely captured by the water absorbent resin. That is, the flying ink immediately dissolves into the water-soluble resin and swells the water-soluble resin, but the water-absorbent resin in the ink-adsorbing layer located immediately below draws the ink into the molecules of the water-absorbent resin. The ink taken into the water-absorbent resin swells the water-absorbent resin but hardly elutes the same, so that it can exhibit extremely excellent water resistance. Therefore, then
Even if the ink jet recording material gets wet with water, the ink does not flow. The outermost heat-resistant layer is 1 μm
In the following manner, most of the printed ink is captured by the ink absorbing layer. Further, if the thickness of the ink absorbing layer is 20 μm or more, almost all of the flying ink can be absorbed.

By using a water-soluble resin that is instantaneously soluble in cold water at 20 ° C., a higher ink absorption speed can be achieved. In addition, polyvinyl alcohol and modified products thereof have a saponification degree of 20 to 90%, more preferably 40 to 90%.
The effect of the present invention is suitably achieved by using a polymer having a viscosity average polymerization degree of 40 to 5,000, preferably 50 to 2,000, particularly 100 to 1,000.

As a water-absorbing resin which can be formed into a film by a dry method such as an extrusion method having excellent productivity, for example, polyethylene oxide is suitable, and as a resin having a sufficient water absorption capacity and no elution amount, General formula (1) already described
The thermoplastic resin shown by these is mentioned. The water-absorbing resin preferably has a water absorption capacity of 10 times or more of its own weight. Further, a water-absorbing material in which the amount of organic carbon pigment eluted from the water-absorbing resin when immersed in water at 25 ° C. for 30 minutes is 0.1% or less is preferable.

Using the ink-jet recording material of the present invention, an image can be recorded by an ordinary ink-jet method, and a good image can be obtained.

Examples of the water-absorbing resin used for the ink-adsorbing layer include thermoplastic resins and the like, such as polyalkylene oxide, water-soluble polyester resin, water-soluble polyurethane resin, cellulose compound, and modified products thereof. Is mentioned. These may be used alone or in combination of one or more.

[0035]

Example 1 Ethylene glycol was added to ethylene oxide, then butylene oxide was added, and ethylene oxide was further added to polyalkylene oxide. Methyl octadecane-1,18-dicarboxylate was added to the resulting mixture. An exchange reaction was performed to obtain a thermoplastic resin having a weight average molecular weight of 150,000. To this, 1 part of tocophenol ("UVINUL2000AO", manufactured by BASF) was blended as a heat stabilizer (sample A). P as a heat-resistant layer resin composition
VA (“CP-1000”, manufactured by Kuraray Co., Ltd.) (Sample B) is prepared, and Sample A and Sample B are respectively charged into a hopper of a two-layer T-die extruder and melted, and the sample is subjected to two-layer co-extrusion. A two-layer film of an ink absorbing layer made of A and a heat-resistant layer made of Sample B was formed. However, the temperature of the T-die is 1
90 ° C., the thickness ratio of the two layers was 30: 2 for the ink-adsorbing layer: heat-resistant layer, and the total thickness of the two-layer film was 32 μm.
Met. Next, the ink-adsorbing layer surface of the obtained two-layer film was laminated on a 100-μm-thick PET film to prepare an ink-jet recording material.

Comparative Example 1 A sample A was prepared in the same manner as in Example 1, and was melt-extruded to obtain a sheet having a thickness of 30 μm. Next, this sheet was laminated on a PET film having a thickness of 100 μm,
An ink jet recording material having only an ink absorbing layer on a substrate and no heat resistant layer was produced.

Comparative Example 2 In the same manner as in Example 1, a film made of a PVA resin was formed by a T-die extrusion method, and was laminated on a PET film having a thickness of 100 μm. An ink-jet recording material having no ink jet was prepared.

With respect to the obtained ink-jet recording material, the printing quality, the drying speed of the ink, the slipperiness of the recording surface, and the heat resistance were evaluated as follows. (1) Print quality Using "DesignJet 2500CP" manufactured by Hewlett-Packard Co., Ltd. as a recording material for inkjet, a uniquely designed pattern is printed in A4 size, and the print state is visually observed to evaluate the print quality. did. However, those having excellent printing quality were indicated by “○”, those having ordinary printing quality were indicated by “△”, and those having poor printing quality were indicated by “×”. (2) Ink drying speed 30 m using "DesignJet 2500CP" manufactured by Hewlett-Packard Co., Ltd. as an ink jet recording material.
A square filled with a size of mx 20 mm was printed. Immediately after printing, 0 minutes, 30 minutes, 60 minutes, 120 minutes,
After 240 minutes, 600 minutes, 1200 minutes, and 2400 minutes, a Kimwipe (manufactured by Crecia Co., Ltd.) was brought into close contact with each other, and the adhesion state of the ink to the Kimwipe and stickiness were examined. After printing, the sample dried within 240 minutes, that is, when 240 minutes had elapsed, no adhesion of the ink to the Kimwipe and no stickiness were recognized, and a symbol “○” was used. (3) Slip property of recording surface Two sheets of ink jet recording material were stacked, a weight of 56 g was placed on the two, and the upper ink jet recording material was pulled at a speed of 100 mm / min, and its frictional resistance was evaluated. did. The symbol "O" indicates that the material can be pulled smoothly without friction, and the symbol "X" indicates that a force is required before the ink jet recording material starts to move. (4) Heat resistance Using "DesignJet 2500CP" manufactured by Hewlett-Packard Co., Ltd. as an ink jet recording material, a uniquely designed pattern is printed on an A4 size plate, and 50 of these are superimposed, and a hot air dryer at 100 ° C. It was left inside for 6 hours. The blocking property of the sample after standing was evaluated. Here, the symbol “○” indicates that there was no blocking and no tack was generated, “△” indicates that there was no blocking but slight tack was observed, and “×” indicates that blocking occurred. Table 1 shows the results.

[0039]

[Table 1]

As is evident from Table 1, it was found that the ink jet recording material of Example 1 of the present invention was excellent in both print quality and handleability. On the other hand, with the ink jet recording material having no heat resistant layer as in Comparative Example 1, the handling of the user was poor in terms of slipperiness and heat resistance. In the case of an ink jet recording material having no ink absorbing layer as in Comparative Example 2, good printing quality cannot be expected and the ink drying speed is low because the ink absorbing ability and the dye holding ability are low. In addition, when a filler such as talc was added to the heat-resistant layer of Comparative Example 2, it was not possible to improve the slipperiness of the recording surface, the printing quality, and the like. That is, only by adopting the constitution of the present invention, it is possible to obtain an ink jet recording material which can simultaneously satisfy all the characteristics.

Example 2 Ethylene glycol was subjected to addition polymerization with ethylene glycol, then butylene oxide was subjected to addition polymerization, and polyalkylene oxide obtained by addition polymerization of ethylene oxide was added with methyl octadecane-1,18-dicarboxylate, followed by transesterification. The reaction was performed to obtain a thermoplastic resin having a weight average molecular weight of 150,000. To this, 1 part of tocophenol ("UVINUL2000AO", manufactured by BASF) was blended as a heat stabilizer (sample A). PVA as resin for heat resistant layer
(“CP-1000”, manufactured by Kuraray Co., Ltd.) (Sample B) was prepared, and Sample A and Sample B were respectively charged into a hopper of a two-layer T-die extruder and melted, and Sample A was subjected to two-layer co-extrusion. And a heat-resistant layer composed of Sample B was formed. However, the temperature of the T-die is 190 ° C
And the thickness ratio of the two layers is: ink-adsorbing layer: heat-resistant layer = 3
1.5: 0.5, the total thickness of the two-layer film is 32μ
m. Next, the ink-absorbing layer of the obtained two-layer film was laminated on a PET film having a thickness of 100 μm to prepare an inkjet base material.

Example 3 A sample A was prepared in the same manner as in Example 2, and was extruded to obtain a sheet having a thickness of 31.5 μm. Next, the film was laminated on a PET film having a thickness of 100 μm to form a film having an ink absorbing layer formed on a substrate. afterwards,
On the ink adsorption layer, PVA (“Gosefimer 20”
0 "(manufactured by Nippon Synthetic Chemical Co., Ltd.) in water was coated with a gravure coater to a dry film thickness of 0.5 μm to prepare an ink jet recording material.

Example 4 After addition polymerization of ethylene glycol with ethylene oxide, butylene oxide was addition-polymerized, and polyalkylene oxide obtained by addition polymerization of ethylene oxide was added with methyl octadecane-1,18-dicarboxylate, followed by transesterification. Was carried out to obtain a thermoplastic resin having a weight average molecular weight of 150,000. Tocophenol ("UVINUL2000AO", manufactured by BASF) was added as a heat stabilizer.
(Sample A). This is melt extruded to 31.5μ
m was obtained. Next, a 100 μm thick P
A film in which an ink absorbing layer was formed on a substrate was laminated on an ET film. Then, a solution obtained by dissolving a urethane resin (“Pateracol A-60”, manufactured by Dainippon Ink Co., Ltd.) (sample B) in water as a resin for the heat-resistant layer on the ink-adsorbing layer with a gravure coater was used. 0.5
It was coated to a thickness of μm to prepare an ink jet recording material.

With respect to the obtained ink-jet recording material, the above-mentioned heat resistance was evaluated.

[0045]

[Table 2]

As is clear from Table 2, the ink-jet recording materials of Examples 2 to 4 having the heat-resistant layer made of a polyvinyl alcohol-based resin or the heat-resistant layer made of urethane did not cause blocking or tack. In addition, the recording materials for inkjet of Examples 2 to 4 were also excellent in scratch resistance. Further, as is apparent from Examples 2 to 4, the heat-resistant layer could be formed by coextrusion or coating.

Example 5 After addition polymerization of ethylene glycol with ethylene oxide, butylene oxide was addition-polymerized, and methyl octadecane-1,18-dicarboxylate was added to the polyalkylene oxide obtained by addition polymerization of ethylene oxide, followed by transesterification. Was carried out to obtain a thermoplastic resin having a weight average molecular weight of 150,000. Tocophenol ("UVINUL2000AO", manufactured by BASF) was added as a heat stabilizer.
Parts (Sample A). The sample A was put into a hopper of a T-die, and was melt-extruded on a PET having a thickness of 100 μm to prepare a laminated film having an ink absorbing layer having a thickness of 30 μm. However, the temperature of the T-die was 190 ° C. 45 parts of an aqueous dispersion of a polyurethane resin having an alkylene oxide chain having an average particle diameter of 0.2 μm (“Hydran HW-970”, manufactured by Dainippon Ink and Chemicals, Inc.) as the resin composition for a heat-resistant layer A mixture of an aqueous dispersion of a carboxylic acid group-containing polyolefin and an aqueous dispersion of a copolymer of ethylene and an α, β-ethylenically unsaturated carboxylic acid (“Chemie Pearl S-100”, manufactured by Mitsui Chemicals, Inc.) An aqueous dispersion of a sulfonic acid group-containing polyurethane resin (“Hydran HW-920”, manufactured by Dainippon Ink and Chemicals, Inc.) was used as a solid content, 5 parts as a solid content, and 5 parts as an acetoacetylated polyvinyl alcohol (“Go Sephimer Z-200 "(manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) as a solid content of 50 parts, epichlorohydrin polyamide resin (" W
S535 ", manufactured by Nippon PMC) (Sample B). Next, the sample B was coated on the heat-resistant layer of the produced laminated film using a bar coater so that the thickness after drying was 2 μm, and dried at a temperature of 120 ° C. for 10 seconds to obtain an inkjet recording material. Was prepared.

Example 6 In Example 5, an aqueous dispersion of a polyurethane resin having an alkylene oxide chain having an average particle size of 0.2 μm (“Hydran HW-9”) was used as the resin composition for the heat-resistant layer.
70 "(manufactured by Dainippon Ink and Chemicals, Incorporated) was used in the same manner as in Example 5 to prepare an ink jet recording material.

Comparative Example 3 A sample A was prepared in the same manner as in Example 5, and was extruded to obtain a sheet having a thickness of 30 μm. Next, this sheet was laminated on a PET film having a thickness of 100 μm,
An ink jet recording material having only an ink absorbing layer on a substrate and no heat resistant layer was produced.

Comparative Example 4 In the same manner as in Example 5, a sample B comprising a resin composition for a heat-resistant layer was coated on a PET film having a thickness of 100 μm, and only a heat-resistant layer was provided and no ink-adsorbing layer was provided. A recording material for inkjet was produced. However, the thickness of the heat-resistant layer after drying was 10 μm.

With respect to the obtained ink-jet recording material, print quality, ink absorption, and heat resistance were evaluated by the above-described methods in the following manner.

[0052]

[Table 3]

As is evident from Table 3, the ink jet recording materials of Examples 5 to 6 of the present invention were found to be excellent in both print quality and handleability. On the other hand, in the case of the ink jet recording material having no heat resistant layer as in Comparative Example 3, the handling of the user was poor in terms of heat resistance. As in Comparative Example 4, in the case of an ink jet recording material comprising only a thin heat-resistant layer formed by coating, good absorption quality and dye holding ability are low, so that good printing quality cannot be expected and ink absorption is also low. Was not enough.

[0054]

As described above, the ink jet recording material of the present invention is excellent in heat resistance, blocking resistance, scratch resistance and slipperiness, and can obtain excellent print quality.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Jun Nishioka 5-8, Mitsuya-cho, Nagahama-shi, Shiga Prefecture Mitsubishi Plastics Co., Ltd. Nagahama Plant F-term (reference) 2C056 EA13 FC06 2H086 BA13 BA15 BA34 BA35

Claims (6)

[Claims] 1. An ink-jet recording material comprising a substrate and an ink-absorbing layer containing a water-absorbing resin as a main component and a heat-resistant layer as an outermost layer. 2. A resin composition wherein the water-absorbing resin contains at least one selected from the group consisting of polyalkylene oxides, water-soluble polyester resins, water-soluble polyurethane resins, cellulose compounds, and modified products thereof. 2. The ink jet recording material according to claim 1, wherein the ink jet recording material is made of a material. 3. The water-absorbent resin is represented by the following general formula (1): Where a, b and c are each an integer of 1 or more, and a weight ratio calculated from a, b and c, 44 (a + c)
/ (Molecular weight of α-olefin oxide having 3 or more carbon atoms)
b, is 80/20 to 94/6, X ₁ is a residue of an organic compound having two active hydrogen groups, Z is a hydrocarbon group having 1 or more carbon atoms, R ₁₁ is a residue of a dicarboxylic acid compound or diisocyanate. The recording material for inkjet according to claim 1, which is a compound residue. 4. The ink-jet recording material according to claim 1, wherein the heat-resistant layer is made of a resin composition containing a polyvinyl alcohol-based resin or a urethane-based resin as a main component. . 5. The heat-resistant layer according to claim 1, wherein the heat-resistant layer comprises a composition containing a polyurethane resin emulsion having an alkylene oxide chain in a molecule and having an average particle diameter of 3.0 μm or less. The recording material for inkjet according to any one of the preceding claims. 6. The heat-resistant layer comprises (A) an aqueous dispersion of a polyolefin having a carboxylic acid group in the molecule, (B) ethylene, and α having an acid group partially neutralized with a basic compound. A composition comprising: an aqueous dispersion of a copolymer of styrene and a β-ethylenically unsaturated carboxylic acid; and (C) an aqueous dispersion of a polyurethane resin having a sulfonic acid group. 6. The inkjet recording material according to any one of 1, 2, 3, and 5.