JP2000280605A - Ink jet recording sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording sheet having scarcely yellowing on white paper and high gloss and high color developability. SOLUTION: In the ink jet recording sheet comprising at least one ink receptive layer and a gloss developing layer sequentially laminated on one surface of a support, as the support, acidic paper is used. Further, as a main component of the receptive layer, a porous synthetic noncrystalline silica is used, as a main component of the developing layer, an alumina hydrate or a colloidal silica is used, the developing layer is brought into pressure contact with a heated mirror surface roll before the developing layer is in a wet state, dried and coated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glossy ink jet recording sheet applicable to a printer using an ink jet recording method, and more particularly to a high glossiness and high color developing property in which white paper is improved in yellowing. It relates to an ink jet recording sheet.

[0002]

2. Description of the Related Art In an ink jet recording system, fine droplets of ink are caused to fly according to various operating principles and adhere to a recording sheet such as paper to record images and characters.
The recording method has features such as high speed, low noise, easy multi-coloring, great flexibility in recording patterns, and no need for development and fixing. It is rapidly spreading in applications. Further, the image formed by the multi-color inkjet method is
It is possible to obtain a record comparable to that of multicolor printing and color photographic printing, and in applications where the number of copies required is small, it is cheaper than photographic technology, so it is widely used in the full color image recording field It is being applied.

Further, in the printer using the ink jet system, the resolution is increased and the color reproduction range is expanded in response to a demand for further improvement in image quality from the market. Along with this, it is indispensable for the inkjet recording sheet as a recording medium to secure a high ink receiving capacity for exhibiting excellent image quality and to apply a coating layer having good coloring properties. In addition, it has been demanded that appearance such as gloss, rigidity and hue and long-term storage properties are similar to silver halide photographs and printing paper.

[0004] Various attempts have been proposed for ink jet recording sheets to achieve a quality comparable to silver halide photography. For example, in order to enhance the color developing property, it is necessary to suppress scattering of light to have transparency and to distribute a large amount of ink on the surface. In response to this request, JP-A-7-82694 and 5-3241
No. 3, 9-99627 and the like disclose a method for obtaining an ink jet recording sheet by applying alumina hydrate, which is a cationic colloid particle, on a support.

In order to increase the gloss, for example, JP-A-2-113986 discloses a method of casting with an aqueous solution containing a cationic polymer electrolyte, and JP-A-2-274587 discloses a method of improving the gloss. For this purpose, a method of using colloidal silica, treating with an aqueous solution containing a cationic polymer electrolyte, and then casting has been proposed.

On the other hand, when an ink jet recording sheet is used as a substitute for a silver halide photograph, storage stability is an important required characteristic as well as appearance such as image quality and gloss. When a silver halide photograph is stored for a long period of time, it is usually stored in a transparent file such as an album or a clear book. When an ink jet recording sheet is stored in these files, a phenomenon in which the white paper turns yellow in the vicinity of the entrance of the file that is exposed to the air is observed. When such discoloration occurs, particularly in an ink jet recording sheet having an image quality comparable to that of a silver halide photograph, a remarkable decrease in quality such as a change in hue of an image portion is caused.

[0007]

SUMMARY OF THE INVENTION An object of the present invention to solve the above-mentioned problems is to provide an ink jet recording sheet having a high gloss and a high coloring property, in which white paper is unlikely to turn yellow when a file is stored.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, have arrived at the present invention.

[0009] An ink jet recording sheet comprising at least one ink receiving layer and a glossy layer sequentially laminated on one side of a support, wherein the support is acidic paper. It is an invention. Here, the acidic paper in the present invention is a paper that is usually formed into a pulp slurry by adding a sulfuric acid band as a fixing agent, rosin as a sizing agent, and other additives such as a binder, and then in an acidic region. .

When the gloss-developing layer comprises a coating composition containing either alumina hydrate or colloidal silica, the transparency of the gloss-developing layer is increased and more ink is distributed on the surface layer. This is preferable since the coloring property can be enhanced.

When the glossy layer is applied by pressing against a heated mirror roll in a wet state and then drying,
This is preferable because high gloss can be easily obtained without impairing the ink absorbency.

Further, when the ink receiving layer is composed of a coating composition containing porous synthetic amorphous silica as a main component, it is more preferable because the ink absorbency is enhanced.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

The present invention is an ink jet recording sheet having high gloss and high color development, in which white paper is unlikely to yellow during storage of a file.

When an ink jet recording sheet is stored in a file and stored, the yellow discoloration near the entrance of the file which is exposed to the air may be caused by 2,6-di-tert-butyl-4-methylphenol or the like contained in the file itself. The antioxidant migrates to the ink jet recording sheet and becomes a compound having a quinone structure through an oxidation reaction,
It is presumed that the ink jet recording sheet was yellowed.

The inventor has used an acidic paper as a support, provided an ink receiving layer made of a specific pigment on one surface thereof, and further provided a glossy layer containing the specific pigment on the ink receiving layer in a wet state. It was found that the white paper was hardly yellowed at the time of storing the file, and high gloss and color developing property were obtained by applying pressure to the heated mirror roll and drying the coating, and the present invention was completed.

The support used in the present invention includes LB
Chemical pulp such as KP, NBKP, GP, PGW, RM
Wood pulp such as mechanical pulp such as P, TMP, CTMP, CMP and CGP, waste paper pulp such as DIP, kenaf, etc.
Non-wood pulp such as bagasse and cotton, and conventionally known pigments such as talc and kaolin as main components, fixing agents such as sulfate bands, sizing agents such as rosin, binders and retention improvers, cationizing agents, paper strength One or more kinds of additives such as a strengthening agent are mixed and used, and acidic paper made by various apparatuses such as a fourdrinier paper machine, a round paper machine, and a twin wire paper machine in an acidic region is used.

It is presumed that by using acidic paper as the support of the ink jet recording sheet of the present invention, the surface pH of the ink jet recording sheet becomes acidic and the yellowing of the antioxidant is suppressed.

Further, the support may be coated with starch, polyvinyl alcohol or the like by size pressing or base paper provided with an anchor coat layer, or art paper, coated paper, cast coated paper, etc. provided with a coat layer thereon. Paper is also included in the support usable in the present invention. Such a base paper and a coated paper may be provided with the ink receiving layer according to the present invention as they are, or a calendar device such as a machine calendar, a TG calendar, or a soft calendar may be used for the purpose of controlling flattening. good. Further, the basis weight of the support is usually 40 to
It is 300 g / m ² , but is not particularly limited.

In the ink receiving layer according to the present invention, one or more of the following pigments or particles can be used. For example,
Light calcium carbonate, heavy calcium carbonate, magnesium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate,
Satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica, alumina, alumina hydrate, aluminum hydroxide, lithopone, zeolite, hydrohalosite,
Examples include white inorganic pigments such as magnesium hydroxide and the like, organic pigments such as styrene-based plastic pigment, acrylic-based plastic pigment, polyethylene, microcapsules, urea resin, and melamine resin. Among the above, as the pigment contained as a main component in the ink receiving layer, a porous inorganic pigment is preferable, and examples thereof include porous synthetic amorphous silica, porous magnesium carbonate, and porous alumina.
In particular, when porous synthetic amorphous silica having a particularly large pore volume is used, sufficient coating layer voids can be obtained in the ink receiving layer, and the ink absorbency increases, which is more preferable.

The binder to be mixed in the ink receiving layer includes starch derivatives such as oxidized starch, etherified starch and phosphate esterified starch; cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose; casein, gelatin, soy protein, polyvinyl Alcohols or derivatives thereof; conjugated diene-based copolymer latexes such as polyvinylpyrrolidone, maleic anhydride resin, styrene-butadiene copolymer, methyl methacrylate-butadiene copolymer; polymers or copolymers of acrylates and methacrylates Acrylic polymer latex such as coalesce; vinyl polymer latex such as ethylene-vinyl acetate copolymer; or functional group-modified polymer latex with functional group-containing monomer such as carboxy group of these various polymers; or Various weights Cationized using a cationic group in the polymer, cationized polymer surface with a cationic surfactant, polymerized under cationic polyvinyl alcohol, and the polyvinyl alcohol is distributed on the polymer surface, cation Polymerization is carried out in a suspension dispersion of conductive colloid particles, and the particles are distributed on the polymer surface; an aqueous binder such as a thermosetting synthetic resin such as a melamine resin and a urea resin; an acrylic such as a polymethyl methacrylate Acid ester or methacrylic acid ester polymer or copolymer resin; polyurethane resin, unsaturated polyester resin,
Synthetic resin binders such as vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, and alkyd resin can be exemplified.

The amount of the binder in the ink receiving layer is as follows:
It is 5 to 70 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the pigment. If the amount is less than 5 parts by weight, the coating layer strength of the ink receiving layer will be insufficient, and if it exceeds 70 parts by weight, the ink absorbency will be undesirably reduced.

In the ink receiving layer, other additives such as a pigment dispersant, a thickener, a flow improver, a defoamer,
Foam inhibitors, release agents, foaming agents, penetrants, coloring dyes, coloring pigments, optical brighteners, ultraviolet absorbers, antioxidants, preservatives,
An anti-binder, a water-proofing agent, a dye fixing agent and the like can be appropriately blended.

The ink receiving layer is formed on or off by using various devices such as various blade coaters, roll coaters, air knife coaters, bar coaters, rod blade coaters, curtain coaters, short dwell coaters, and size presses. More than one layer is applied.

The coating amount of the ink receiving layer varies depending on the type and amount of the pigment or binder to be applied and the type of the ink jet recording apparatus, but is 2 g / m ² or more, preferably 4 g / m ² or more.
２０20 g / m ² .

After the ink receiving layer is applied and dried, before coating the glossy layer on the ink receiving layer, a machine calendar, a TG calendar, a soft calendar, a super calendar, etc. The calendar device may be used on-machine or off-machine. The flattening is preferable because the gloss of the ink jet recording sheet after applying the glossy layer is enhanced, but when the flattening treatment is performed excessively, the coating layer voids in the ink receiving layer become too small, and the Care must be taken since the absorbency may be significantly impaired.

The following pigments or particles can be used in an appropriate combination in the gloss developing layer according to the present invention. For example, light calcium carbonate, heavy calcium carbonate, magnesium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate , Synthetic amorphous silica, colloidal silica, alumina, alumina hydrate,
Examples include white inorganic pigments such as aluminum hydroxide, lithopone, zeolite, hydrohalosite, and magnesium hydroxide, and organic pigments such as styrene-based plastic pigment, acrylic-based plastic pigment, polyethylene, microcapsules, urea resin, and melamine resin. Among the above, in particular, alumina hydrate or colloidal silica, in particular, cationic colloidal silica, enhances the transparency of the glossy layer, and enhances the color development by distributing a large amount of ink on the surface layer. Therefore, it is preferable.

The binder to be incorporated in the glossy layer includes starch derivatives such as oxidized starch, etherified starch and phosphated starch; cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose; casein, gelatin, soy protein, polyvinyl Alcohols or derivatives thereof; polyvinylpyrrolidone, maleic anhydride resin, styrene-butadiene copolymer, conjugated diene-based copolymer latex such as methyl methacrylate-butadiene copolymer, etc .; polymer or copolymer of acrylate and methacrylate Acrylic polymer latex such as coalesce; vinyl polymer latex such as ethylene-vinyl acetate copolymer; or functional group-modified polymer latex with functional group-containing monomer such as carboxy group of these various polymers; or Various polymerizations Cationized using a cationic group, a cationized polymer surface with a cationic surfactant, polymerized under cationic polyvinyl alcohol and the polyvinyl alcohol is distributed on the polymer surface, cationic Polymerization is performed in a suspension dispersion of colloidal particles, and the particles are distributed on the polymer surface; an aqueous binder such as a thermosetting synthetic resin such as a melamine resin or a urea resin; an acrylic acid such as a polymethyl methacrylate Ester or methacrylic acid ester polymer or copolymer resin; polyurethane resin, unsaturated polyester resin,
Synthetic resin binders such as vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, and alkyd resin can be exemplified.

The compounding amount of the binder in the glossy layer is as follows:
It is 5 to 70 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the pigment. If the amount is less than 5 parts by weight, the coating strength of the glossy layer is insufficient, and if it is more than 70 parts by weight, the ink absorbency is undesirably reduced.

In the glossy layer, other additives such as a pigment dispersant, a thickener, a flow improver, an antifoaming agent, a foam inhibitor, a release agent, a foaming agent, a penetrant, a coloring agent, Dyes, coloring pigments,
A fluorescent whitening agent, an ultraviolet absorber, an antioxidant, an antiseptic, an antibacterial agent, a waterproofing agent, a dye fixing agent, and the like can also be appropriately compounded.

The glossy layer is formed on the ink-receiving layer by using various devices such as various blade coaters, roll coaters, air knife coaters, bar coaters, rod blade coaters, curtain coaters, short dwell coaters, and size presses. It is applied by machine or off-machine.

After applying the glossy layer and drying it, a machine calender, a TG calender,
A calender such as a soft calender or a super calender may be used on-machine or off-machine. However, if excessive calendering is performed, the pore volume in the gloss-developing layer is significantly reduced, and the ink absorbency is reduced. You need to be aware of this.

Further, when the glossy layer is applied by being pressed against a heated mirror roll in a wet state and dried, the mirror shape of the roll is transferred to an ink jet recording sheet. This is preferable because the surface smoothness becomes extremely high and a strong gloss is obtained. At this time, since the linear pressure at the time of pressing against the mirror roll is lower than when a calender is used, the pore volume of the gloss-developing layer is not significantly reduced, and good ink absorption is obtained. Is more preferable.

The method of pressing and drying a heated mirror roll in a wet state according to the present invention is generally the same as the production method of a cast coated paper for printing, and includes a direct method, a coagulation method, and a rewet method ( Rewet method). The direct method is a method in which after a glossy layer is applied, the coated layer is pressed against a heated mirror roll in an undried state (wet state) and dried. The coagulation method is a method in which after a glossy layer is applied, the undried layer is coagulated with a coagulation liquid, and then pressed against a heated mirror-finished roll and dried. The rewet method is a method in which a gloss-developing layer is applied, dried, then rewet with a wetting liquid mainly composed of water, and then pressed against a heated mirror surface and dried. The surface roughness, diameter, pressure (linear pressure) during pressing and coating speed of the mirror roll according to the method can be appropriately selected in the same manner as the production conditions of commercially available cast-coated paper.

[0035] As the coating amount of the glossy layer, the type and amount of pigment and binder to be applied may vary depending on the type of the ink jet recording apparatus, 2 g / m ² or more, preferably in the range of 4~20g / m ² It is.

The ink-jet recording sheet according to the present invention may be used not only as an ink-jet recording sheet but also as any recording sheet using a liquid ink at the time of recording. For example, a heat-fusible substance, a heat-fusible ink containing a dye, a pigment or the like as a main component is applied to a thin support such as a resin film, high-density paper, or synthetic paper, and an ink sheet is heated from the back surface thereof. Heat transfer recording image-receiving sheet for melting and transferring the ink, heat-fusible ink is heated and melted to form fine droplets, ink jet recording sheet for flight recording, ink jet recording sheet using ink in which oil-soluble dye is dissolved in solvent, light An image receiving sheet corresponding to a photosensitive pressure-sensitive donor sheet using microcapsules containing a polymerizable monomer and a colorless or colored dye or pigment is included.

The common feature of these recording sheets is that the ink is in a liquid state at the time of recording. The liquid ink permeates or spreads in the depth direction or the horizontal direction of the ink receiving layer of the recording sheet until it is cured, solidified or fixed.
The above-described various recording sheets require absorptivity according to each system, and the ink jet recording sheet of the present invention may be used as the above-described various recording sheets.

Further, the ink-jet recording sheet of the present invention may be used as a recording sheet for heating and fixing an electrophotographic toner widely used in copiers, printers and the like, or a label provided with an adhesive layer. It is also possible to use it for applications.

[0039]

EXAMPLES The present invention will be described below with reference to examples of the present invention, but the present invention is not limited to these examples.
Parts and% shown in Examples are parts by weight and% by weight of solid content unless otherwise specified.

<Preparation of Support A> LBKP (freeness of 40)
0mlcfs) 90 parts and NBKP (freeness 450mlc)
fs) 10 parts of wood pulp consisting of 10 parts, 10 parts of talc, 3 parts of sulfuric acid band, 0.2 part of commercially available rosin sizing agent, 0.3 part of commercially available cationized starch, and then fourdrinier papermaking After the paper was made to have a basis weight of 125 g / m ² by using a machine, a commercially available oxidized starch was adhered using an on-machine in-line press machine to obtain an acidic base paper having a basis weight of 127 g / m ² . The acidic base paper was used as support A.

<Preparation of Support B> LBKP (freeness of 40)
0mlcfs) 90 parts and NBKP (freeness 450mlc)
fs) 10 parts of wood pulp consisting of 10 parts, 10 parts of light calcium carbonate, 0.1 part of commercially available alkyl ketene dimer, 0.1 part of commercially available cationic polyacrylamide.
After preparing 05 parts and 1.0 part of a commercially available cationized starch, the resulting product was formed into a basis weight of 125 g / m ² using a fourdrinier paper machine, and then a commercially available oxidized starch was prepared using an on-machine inline size press machine. This was applied to obtain a neutral base paper having a basis weight of 127 g / m ² . The neutral base paper was used as support B.

Example 1 An ink-receiving layer was obtained by coating a coating composition on a support A. The coating composition was made of commercially available porous synthetic amorphous silica (Fine Seal X37B: manufactured by Tokuyama Corporation) as a pigment.
00 parts, 40 parts of a commercially available polyvinyl alcohol (PVA117: manufactured by Kuraray Co., Ltd.) as a binder, and a commercially available cationic fixing agent (Sumilez Resin 1001: manufactured by Sumitomo Chemical Co., Ltd.)
20 parts were obtained. The solid concentration of the coating composition is 17
%. The coating composition was applied on the support A so as to have an absolute dry weight of 10 g / m ² by an air knife coater and dried, and then subjected to machine calendering on-machine to obtain an ink receiving layer. .

Next, the coating composition was applied on the ink receiving layer applied on the support A to obtain a gloss developing layer. The coating composition was prepared by using 70 parts of a commercially available alumina sol (Cataloid AS-3: manufactured by Catalysis Chemical Co., Ltd.) as a pigment, 30 parts of a commercially available cationic colloidal silica (Snowtex AK: manufactured by Nissan Chemical Co., Ltd.), and commercially available as a binder. Of polyvinyl alcohol (PVA117: manufactured by Kuraray Co., Ltd.). The solid content concentration of the coating composition is 12%. The coating composition was dried with an air knife coater in an absolute dry coating amount of 5 g /
m ² was applied onto the ink receiving layer, dried, and then subjected to on-machine machine calendering to obtain an ink jet recording sheet of Example 1.

Example 2 A coating composition was applied on the ink receiving layer obtained in the same manner as in Example 1 to obtain a glossy layer. The coating composition contains 70 parts of a commercially available alumina hydrate (Cataloid AS-3: manufactured by Catalyst Chemicals Co., Ltd.) as a pigment, 30 parts of a commercially available cationic colloidal silica (Snowtex AK: manufactured by Nissan Chemical Co., Ltd.),
Commercially available polyvinyl alcohol (PVA) as a binder
117: Kuraray Co., Ltd.) and 1 part of a commercially available nonionic oleic acid emulsion (DEF7100: Nissin Chemical Co., Ltd.) as a release agent. The solid content concentration of the coating composition is 12%. The coating composition was coated on the ink receiving layer with an air knife coater so that the absolute dry coating amount was 5 g / m ^2, and a mirror surface roll having a surface temperature kept at 100 ° C. in a wet state And dried for 10 seconds to obtain an ink jet recording sheet of Example 2.

Example 3 A coating composition was applied on the ink receiving layer obtained in the same manner as in Example 1 to obtain a glossy layer. The coating composition contained 30 parts of a commercially available alumina hydrate (Cataloid AS-3: manufactured by Catalysis Chemical Co.) as a pigment, 70 parts of a commercially available cationic colloidal silica (Snowtex AK: manufactured by Nissan Chemical Co., Ltd.),
Commercially available polyvinyl alcohol (PVA) as a binder
117: Kuraray Co., Ltd.) and 1 part of a commercially available nonionic oleic acid emulsion (DEF7100: Nissin Chemical Co., Ltd.) as a release agent. The solid content concentration of the coating composition is 14%. The coating composition was coated on the ink receiving layer with an air knife coater so that the absolute dry coating amount was 5 g / m ^2, and a mirror surface roll having a surface temperature kept at 100 ° C. in a wet state And dried for 10 seconds to obtain an ink jet recording sheet of Example 3.

Example 4 A coating composition was applied on the ink receiving layer obtained in the same manner as in Example 1 to obtain a gloss developing layer. In the coating composition, 100 parts of commercially available alumina hydrate (Cataloid AS-3: manufactured by Catalyst Chemical Co., Ltd.) as a pigment and 20 parts of commercially available polyvinyl alcohol (PVA117: manufactured by Kuraray Co., Ltd.) as a binder were used.
And 1 part of a commercially available nonionic oleic acid emulsion (DEF7100: manufactured by Nissin Chemical Co., Ltd.) as a release agent. The solid content concentration of the coating composition is 10%. The coating composition was dried with an air knife coater in an absolute dry coating amount of 5 g / m.
^The ink was coated on the ink receiving layer so that the surface of the ink receiving layer became ² and the surface of the mirror was maintained at 100 ° C in a wet state.
This was pressed for 2 seconds and dried to obtain an ink jet recording sheet of Example 4.

Example 5 A coating composition was applied on the ink receiving layer obtained in the same manner as in Example 1 to obtain a glossy layer. The coating composition had 100 parts of commercially available cationic colloidal silica (Snowtex AK: manufactured by Nissan Chemical Industries) as a pigment, 20 parts of commercially available polyvinyl alcohol (PVA117: manufactured by Kuraray) as a binder, and used as a release agent. One part of a commercially available nonionic oleic acid emulsion (DEF7100: manufactured by Nissin Chemical Co., Ltd.) was prepared and obtained. The solid content concentration of the coating composition is 16%. Coating the coating composition with an air knife coater on the ink receiving layer so that the absolute dry coating amount is 5 g / m ² ;
In a wet state, the sheet was pressed against a mirror roll having a surface temperature kept at 100 ° C. for 10 seconds and dried to obtain an ink jet recording sheet of Example 5.

Example 6 A coating composition was applied on the ink receiving layer obtained in the same manner as in Example 1 to obtain a glossy layer. The coating composition is a commercially available colloidal silica (Snowtex XL:
100 parts of Nissan Chemical Co., Ltd.) and 2 parts of commercially available polyvinyl alcohol (PVA117: Kuraray) as a binder
0 parts and 1 part of a commercially available nonionic oleic acid emulsion (DEF7100: manufactured by Nissin Chemical Co., Ltd.) were prepared as a release agent. The solid content concentration of the coating composition is 16%. The coating composition was dried with an air knife coater in an absolute dry coating amount of 5 g / m.
^The ink was coated on the ink receiving layer so that the surface of the ink receiving layer became ² and the surface of the mirror was maintained at 100 ° C in a wet state.
This was pressed for 2 seconds and dried to obtain an ink jet recording sheet of Example 6.

Comparative Example 1 An ink jet recording sheet of Comparative Example 1 was obtained in the same manner as in Example 2 except that the support B was used.

Table 1 shows the evaluation results for the examples and comparative examples.
Shown in The evaluation shown in Table 1 was performed by the following method.

<White Paper Yellowing> A commercially available polypropylene plastic file bag (A4 size, three types) is cut into a 5 cm × 5 cm square at the center on one side, and the glossy layer side of each ink jet recording sheet has a hole on the file side. And left in a file at 20 ° C. and 65% Rh for 75 days. L ^* a ^* b ^* on the gloss-developing layer side of the inkjet recording sheet before and after saving the file were measured with a color difference meter (CR-200: manufactured by Minolta). The degree of yellowing of blank paper can be represented by the difference (の b ^* ) between b ^* before and after saving the file of each ink jet recording sheet, and a smaller value indicates less yellowing. △ b ^* is 1.5
In the following cases, the color difference is not clear, but
When it is 0 or more, it is felt that it is clearly yellowish. The △ b ^* value in the table is the average value of △ b ^* when each ink jet recording sheet is stored in three types of files.

<Glossiness> The 75-degree specular glossiness of the surface of the glossy layer was measured. The gloss is measured according to JIS Z8741 by using a gloss meter (digital gloss meter GM-26).
D: Murakami Color Research Laboratory).

<Color Development> Black solid printing was performed using a commercially available ink jet printer (BJC420J; equipped with a photo ink cartridge: manufactured by Canon Inc.), and the optical reflection density of the printed portion was measured with a Macbeth densitometer (RD919). .

<Absorptivity> Using the above-described ink jet printer, a grid pattern of white lines (non-printed portion) was created in a mixed color solid pattern composed of cyan ink and magenta ink, and the bleeding of the ink into the grid was determined as follows. It was visually determined by reference. Evaluation C is a level that poses a problem in practical use. A: The lattice is clear. B: The grid becomes narrow, and the ink seeps out slightly. C: The grid is partially missing due to ink seeping.

[0055]

[Table 1]

From Examples 1 to 6 and Comparative Example 1, it can be seen that the use of acidic paper as the support makes it difficult for the white paper to turn yellow, and that high gloss and high color development can be obtained. In addition, when the glossy layer is pressed against a heated mirror roll in a wet state and dried, the glossy layer exhibits higher gloss and better absorbability, indicating that the present invention is more effective.

[0057]

As is clear from the examples, the present invention
By using an acidic paper as a support and sequentially laminating an ink receiving layer and a gloss developing layer, it is possible to provide an ink jet recording sheet having a high gloss and a high color developing property in which the yellowing of white paper is improved. Furthermore, by using a specific pigment for the ink-receiving layer and the gloss-presenting layer, the gloss-presenting layer is pressed against a heated mirror roll in a wet state, and dried and applied, so that it has high gloss and absorptivity. An ink jet recording sheet can be provided.

 ──────────────────────────────────────────────────の Continued on the front page F-term (reference) 2H086 BA02 BA12 BA15 BA33 4F100 AA08 AA08H AA19C AA20B AA20C AC10 AC10H AJ07 AK21 BA03 BA04 BA05 BA07 BA10A BA10C CA13 CC00C DG02 DG10A DJ10B EC01C EH46 EH46 EH46 EH46 AG17 AG18 AG50 AG64 AG94 AG95 AH02 AH09 AH11 AH37 AJ04 BE08 FA11 FA12 FA15 GA09 GA20

Claims (4)

[Claims] 1. An ink jet recording sheet in which at least one ink receiving layer and a glossy layer are sequentially laminated on one surface of a support, wherein the support is acidic paper. Sheet. 2. The ink jet recording sheet according to claim 1, wherein said glossy layer comprises a coating composition containing alumina hydrate and / or colloidal silica as a main component. 3. The ink jet recording sheet according to claim 1, wherein the glossy layer is applied by being pressed against a mirror roll heated in a wet state and dried. 4. The ink jet recording sheet according to claim 1, wherein said ink receiving layer comprises a coating composition containing porous synthetic amorphous silica as a main component.