JPH09164759A - Ink jet recording sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ink jet sheet having brilliant surface glass and exhibiting high ink absorbance while preventing curl or blocking by providing a hydrophilic binder layer added with specified weight of polymer latex particles on a support and providing a hydrophilic binder layer thereon. SOLUTION: Polymer latex particles having refractive index close to that of hydrophilic binder are added by 2-8 times in weight as mush as the hydrophilic binder in order to suppress diffuse reflection. Blocking and the like, caused by particles present on the surface of hydrophilic binder layer, is prevented by at least one hydrophilic binder layer laminated thereon. This structure produces an ink jet recording sheet having good luster. The polymer latex particles are produced of acryl based polymer, olefin based polymer or urethane based polymer.

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 sheet for recording using an aqueous ink, and more particularly to an ink jet recording sheet capable of forming a high quality image while having both excellent ink absorbency and high gloss. It is a thing.

[0002]

2. Description of the Related Art The ink jet recording system is one in which minute droplets of ink are ejected by various operating principles and adhered to a recording sheet such as paper to record an image / character, but at a relatively high speed. It has advantages such as low noise and easy multicoloring. With regard to nozzle clogging and maintenance, which have been a problem with this system, improvements have been made in terms of both ink and equipment, and are now rapidly spreading to various fields such as various printers, facsimiles, and computer terminals. .

A recording sheet used in this ink jet recording system has a high density of print dots, a bright and vivid color tone, and ink flows out quickly even when print dots overlap each other. It is required that the ink does not bleed, that the diffusion of the print dots in the lateral direction is not excessively large, and that the periphery is smooth and does not blur.

In order to meet these requirements, for example, JP-A-52-53012 discloses an ink jet recording sheet obtained by wetting a low-sized base paper with a coating material for surface treatment. Further, in Japanese Patent Laid-Open No. 55-5830,
Ink jet recording sheets having an ink-absorbing coating layer on the surface of a support, and in JP-A-55-51583 and JP-A-56-157, non-colloidal silica powder is used as a pigment in the coating layer. Examples etc. are disclosed.

However, in general, when the ink-receptive ink-absorbing layer has many voids for absorbing and retaining ink, the ink-receptive layer having many voids has a microscopic interface with air or a microscopic surface of the coating film. Since there are many irregularities, the incident light to the ink receiving layer is scattered and the transmission is hindered, so that it becomes difficult to produce gloss and becomes opaque. Furthermore, since it is difficult for light to reach the ink that has penetrated into the voids, the image becomes whitish and the color reproducibility and color density are reduced. It has been difficult to obtain an image with high color reproducibility and color density while maintaining the property.

JP-A-4-41289 discloses an example in which cellulose beads are added, and JP-A-4-235086 discloses an example in which polystyrene beads are added. However, these particles generally have a large particle size and are in view of gloss and transparency. It could not be added in a large amount, and the effect on ink receptivity was insufficient.

JP-A-59-222381 discloses a recording sheet having excellent gloss and transparency, and improved water resistance and light resistance, which comprises a plurality of different pigment layers and a thermoplastic organic polymer fine particle as the outermost layer. An example of a recording sheet comprising the layers contained is disclosed. However, since the ink receiving layer is originally opaque, it is indispensable to dissolve the outermost layer into a film by using an organic solvent or heat after printing. In addition, JP
No. 3-178074 discloses a styrene-butadiene copolymer latex and colloidal silica.
The publication discloses an example of a recording sheet composed of butyl acrylate-2-ethylhexyl acrylate copolymer latex and colloidal silica. However, all of the above patents have insufficient ink absorbency as a full-color inkjet recording sheet, and also have problems such as blocking.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to have high ink absorbability in printing with an aqueous ink and to prevent blocking and curling under environmental humidity. It is an object of the invention to provide an inkjet recording sheet which is improved and has high glossiness and which enables high-quality image formation.

[0009]

The above object of the present invention is to provide a hydrophilic binder layer having 2 to 8 times the weight of polymer latex particles, based on the weight of the hydrophilic binder, as a lower layer, and to provide at least one layer. An inkjet recording sheet characterized by being provided on a support together with a hydrophilic binder layer, a hydrophilic binder layer having the polymer latex particles, is provided adjacent to the outermost hydrophilic binder layer, The hydrophilic binder is a binder capable of reversibly converting into a sol-gel, and 40% by weight or more of the total amount of binder contained in the total hydrophilic binder layer on the support is polyvinyl alcohol. It was

That is, the present inventors have found that it is insufficient to laminate at least one hydrophilic binder layer on a particle-containing hydrophilic binder layer having excellent ink absorbency but insufficient gloss. It is thought that the problem of glossiness can be solved, and in particular, a specific amount of a polymer latex particle having a refractive index which is not significantly different from that of a hydrophilic binder is added to the binder to suppress irregular reflection, and the particles are present on the hydrophilic binder layer surface. It was found that an inkjet recording sheet having good gloss can be obtained by preventing the blocking and the like caused by the above by at least one hydrophilic binder layer laminated on the upper layer, and the present invention has been completed.

Hereinafter, the present invention will be described in detail.

In the ink jet recording sheet of the present invention, the hydrophilic binder layer having 2 to 8 times the weight of the polymer latex particles with respect to the weight of the hydrophilic binder is used as the lower layer and at least one hydrophilic binder layer is formed. It is characterized in that it is provided on a support. Hereinafter, the hydrophilic binder layer provided on the support may be collectively referred to as an ink receiving layer.

The above-mentioned polymer latex particles can be used in the form of an aqueous dispersion of various polymers. Specifically, use of an acrylic polymer, an ester polymer, a urethane polymer, an olefin polymer, a vinylidene chloride polymer, an epoxy polymer, an amide polymer and an aqueous dispersion of a modified product or a copolymer thereof. You can Among these, it is preferable to use acrylic polymers, olefin polymers, urethane polymers,
From the viewpoint of ink absorbency and coating strength of the layer (coating), acrylic polymers and olefin polymers are particularly preferable.

The olefin-based polymer is composed of vinyl monomer-diolefin, and as the vinyl monomer, styrene, acrylonitrile, methacrylonitrile, methyl acrylate, methyl methacrylate, vinyl acetate and the like are preferably used. As the diolefin, Butadiene, isoprene, chloroprene and the like are preferably used. In addition to these components, as the unsaturated carboxylic acid, acrylic acid, methacrylic acid, itaconic acid, maleic anhydride or their alkyl esters, acrolein, methacrolein, glycidyl acrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, methacrylic acid It is preferable to add a crosslinkable component such as 2-hydroxyethyl acid, allyl acrylate, allyl methacrylate, N-methylol acrylamide, N-methylol acrylamide, vinyl isocyanate or allyl isocyanate. The content of diolefin is preferably 10 to 6
It is about 0% by weight.

Examples of acrylic polymers include C ₁
To C ₁₈ linear or branched alkyl groups, phenyl groups, benzyl groups, phenethyl groups, cyclohexyl groups, glycidyl groups, hydroxyl group-containing groups such as 2-hydroxyethyl, 2-hydroxypropyl, etc. Acid ester; acrylonitrile, C ₁ -C
N- or N of ₁₈ linear or branched alkyl groups,
N-acrylamide, acrylic acid or methacrylic acid and their salts, styrene sulfonic acid, vinyl sulfonic acid and their salts, itaconic acid, maleic acid, fumaric acid and their salts, itaconic anhydride, maleic anhydride and other acid anhydrides And a copolymer of vinyl isocyanate, allyl isocyanate, vinyl methyl ether, vinyl acetate, styrene and the like.

Usually, these polymer latex particles are obtained by an emulsion polymerization method. As for the surfactant, polymerization initiator and the like used therein, those used in a conventional method may be used. Regarding the method for synthesizing polymer latex particles, US Pat. Nos. 2,852,368 and 2,852
No. 3,457, No. 3,411,911, No. 3,41
1,912, 4,197,127, Belgian Patents 688,882, 691,360, 712.
No. 823, Japanese Patent Publication No. 45-5331, and Japanese Patent Laid-Open No. 60-18.
No. 540, No. 51-130217, No. 58-1378.
31 and 55-50240.

The average particle size of the polymer latex particles is
About 0.005 to 2.0 μm, preferably 0.01 to
0.8 μm. Further, the glass transition temperature (Tg) of the polymer latex particles is not particularly limited. From the viewpoint of bending strength and the like, a material having a low glass transition temperature and flexibility is preferable, but it can be appropriately selected in consideration of the kind of binder to be used, the amount ratio with the binder, the ink absorbency and the like.

As the hydrophilic binder, known ones can be used. However, when a considerable amount of hydrophilic binder is applied to the support, its production amount and glossiness,
A binder capable of reversibly sol-gel conversion, that is, an aqueous solution of the binder gels (solidifies) at a low temperature, but it is advantageous that it has a property of dissolving at a higher temperature. Examples of such a binder include gelatin and an amino group. Inactivated gelatin, agar and the like can be mentioned, and gelatin or amino group inactivated gelatin is particularly preferable. Acid-processed gelatin and alkali-processed gelatin are used as gelatin.

The amino group-inactivated gelatin is gelatin in which the amino groups of the above gelatin are chemically inactivated. For example, US Pat. Nos. 2,691,582 and 2,61.
4, 928 and 2,525,753 and the like, and examples thereof include acylated gelatin, deaminated gelatin, and gelatin to which isocyanates are added. Preferred amino group-inactivated gelatins are acylated gelatins and isocyanate-added gelatins.

The acylated gelatin is gelatin obtained by treating ordinary gelatin with an acylating agent, and examples thereof include acetylated gelatin, phthalated gelatin, benzoylated gelatin and the like.

As the gelatin to which isocyanates are added, phenylisocyanate-added gelatin is representative.

In the above-mentioned amino group inactivated gelatin,
The blocking rate of the amino group is preferably 10 to 100%. The above gelatin and amino group inactivated gelatin may be used alone or in combination.

When gelatin, amino group deactivated gelatin or the like is used as the binder capable of reversible sol-gel conversion in the hydrophilic binder, polyvinyl alcohol is used from the viewpoint of ink absorbency and curl reduction under environmental humidity. It is preferable to use them together, and in this case, it is preferable that 40% by weight or more is polyvinyl alcohol, based on the total weight of the binder in the ink receiving layer.

Polyvinyl alcohol has a saponification degree of
The degree of polymerization is not particularly limited, but the degree of polymerization is preferably 1000 or less because it has little influence on the viscosity of the coating solution. In addition, the saponification degree is preferably high in terms of water resistance after printing the ink receiving layer.

The above-mentioned polyvinyl alcohol may be modified with cation, carboxylic acid, silicon, etc., if necessary.

Further, as a hydrophilic binder, for example, starch or its derivative, carboxymethyl cellulose,
Cellulose derivatives such as hydroxyethyl cellulose, casein, dextrin, dextran, sodium alginate, polyvinylpyrrolidone, polyacrylic acid, polyethylene glycol (molecular weight 5,000 or more), pullulan, water-soluble gum, and other known natural or synthetic hydrophilic polymers may be used in combination. it can.

In the present invention, the amount of the polymer latex particles to the hydrophilic binder in the hydrophilic binder layer other than the outermost layer (hereinafter referred to as the protective layer), that is, the lower hydrophilic binder layer is 2 to 8 times by weight. It is preferable that it is 2 to 5 times. If the ratio of the polymer latex is less than 2 times, the ink absorbency is insufficient, and if it is more than 8 times, blocking and gloss are adversely affected, and a problem may occur in that the film strength of the layer is lowered.

In the ink jet recording sheet of the present invention, at least one hydrophilic binder layer is laminated on a support together with the hydrophilic binder layer having the above-mentioned specific amount of polymer latex particles with respect to the hydrophilic binder. . The main purpose of the hydrophilic binder layer of the protective layer is to maintain the surface gloss, to provide a proper slipperiness and anti-sticking function, and to control the wetting of the ink. The configuration is especially important.

In particular, when fine particles such as inorganic particles are added to the layer closer to the support than the protective layer in order to enhance the ink absorbency, the gloss tends to deteriorate, and the conditions for the protective layer are important. For this reason, it is not preferable to add a large amount of a matting agent necessary for imparting a proper slipperiness or anti-sticking function, that is, an inorganic pigment or oil drop that deteriorates gloss, or a highly hygroscopic material. Therefore, the hydrophilic binder layer to which the polymer latex particles are added needs to be a layer other than the outermost layer.

When a plurality of hydrophilic binder layers, particularly 3 or more hydrophilic binder layers are provided on the support, it is possible to provide a hydrophilic binder layer having polymer latex particles on the side closer to the support, but mainly the ink. From the viewpoint of absorbability, it is preferably a layer adjacent to the protective layer. The thickness of the hydrophilic binder layer of the protective layer is not particularly limited, but the ink absorbency,
It is appropriately set in consideration of glossiness and blocking property.

The solid coating amount of the hydrophilic binder layer on the ink receiving layer side of the ink jet recording sheet of the present invention, that is, the dry coating amount is not particularly limited, but is generally 5 to 60.
preferably ^{g / m 2, 10~40g / m} 2 is more preferable. Note that, from the viewpoint of preventing curl after forming a recorded image, it is preferable to form the recording image as thin as possible.

The subbing layer, which is optionally provided for coating the hydrophilic binder layer on the support, is a hydrophilic layer of the present invention when they are coated substantially during the production of the support. Not included in sex binders.

In the present invention, the following pigments can be added to the extent that the gloss and transparency of the hydrophilic binder layer are not impaired. As the pigment, one or more known white pigments can be used, and examples thereof include light calcium carbonate, heavy calcium carbonate, magnesium carbonate, kaolin, clay, talc, mica, 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, colloidal alumina, pseudo-boehmite, aluminum hydroxide, lithopone, zeolite, hydrohaloysite, magnesium hydroxide, potassium titanate, smectite, montmorillonite, hydrotalcite, etc. And white inorganic pigments, styrene plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, urea resins, melamine resins and the like.

In the hydrophilic binder layer, a polycationic polyelectrolyte as disclosed in JP-A-56-84992, a basic latex polymer as disclosed in JP-A-57-36692, and JP-B-4-15744 are used as water-proofing agents for images. JP 61-58
One or more of polyallylamine described in JP-A No. 788, 62-174184 and weak alkali metal salt described in JP-A No. 61-47290 can be used. The waterproofing agent may be added to the same layer as the latex polymer particle-added layer of the present invention or may be divided into different layers.

The hydrophilic binder layer may further contain a UV absorber, an antioxidant, a dispersant, a fluorescent dye, and p if necessary.
Various known additives such as an H-adjusting agent, a defoaming agent, a lubricant, an antiseptic, a surfactant, a thickener, a cross-linking agent, an antistatic agent and a matting agent can be contained. As these additives, additives having two or more functions may be added to a single layer, or additives having the same function may be divided into two or more layers and added.

The ink receiving layer can be formed by coating the obtained coating liquid on the above support and drying by heating. The coating is, for example, a dip coating method, a roll coating method, a curtain coating method, a rod bar coating method, an air knife coating method, a spray coating method or an extrusion coating method using a hopper described in US Pat. No. 2,681,294. The known coating method can be used. As needed,
U.S. Pat. Nos. 2,761,791 and 3,508,94
No. 7, No. 2,941,898 and No. 3,526,52
No. 8, Yuji Harasaki, "Coating Engineering," page 253 (19
It is also possible to apply two or more layers by the method described in Asakura Shoten, 1973, etc.).

In the production of the ink jet recording sheet of the present invention, all the coating liquids constituting the ink receiving layer side are simultaneously coated on a support, preferably after cooling and solidifying (so-called set), the water is evaporated. It is preferable to carry out the treatment by drying. The coating is preferably a curtain coating method or the above-mentioned US Pat. No. 2,681,
The extrusion coating method using the hopper described in No. 294 is preferably used. At this time, it is preferable from the viewpoint of productivity that the coating liquid set in the drying step is heated under the condition that the coating liquid does not dissolve again. Normally, after evaporating water to some extent within the range of room temperature to 30 ° C after setting, 4
It is heated to 0 ° C to 50 ° C and completely dried.

As the support, any conventionally known support can be used without particular limitation. Suitable materials for the transparent support include, for example, polyester resin, diacetate resin, triacetate resin, acrylic resin, polycarbonate resin, polyvinyl chloride resin, polyimide resin, cellophane, celluloid, etc. Examples thereof include films, plates, and glass plates. Among them, those having a property of withstanding radiant heat when used as OHP are preferable, and polyethylene terephthalate is particularly preferable. The thickness of such a transparent support is approximately 10 to 10.
200 μm is preferable. Further, a preferable support used when it is not necessary to be transparent is, for example, a sheet or plate made of general paper, synthetic paper, resin-coated paper, cloth, wood, metal, etc., and the above-mentioned translucent support. And the like, which have been opaque-treated by a known means. As the opaque support, a resin-coated paper (so-called RC paper) having a polyolefin resin-coated layer obtained by adding a white pigment or the like to at least one of the base paper, and a so-called white pet obtained by adding a white pigment to polyethylene terephthalate are preferable. For the purpose of increasing the adhesive strength between the support and the ink receiving layer, it is preferable to subject the support to corona discharge treatment, subbing treatment, etc. prior to coating the ink receiving layer. Further, the recording sheet of the present invention does not necessarily need to be colorless, and may be a colored recording sheet.

[0039]

The present invention will be described below with reference to examples of the present invention.
The present invention is not limited to these examples. In addition,
In the examples, "%" indicates absolutely dry weight% unless otherwise specified, and the addition amount indicates the amount per 1 m ^{2 of the} inkjet recording sheet.

Example 1 << Preparation of Inkjet Recording Sheet >> A paper support (thickness 130) having both sides coated with polyethylene of 80 g / m ²
μm, containing 7% by weight of titanium oxide in the polyethylene layer on the recording surface side) 0.1 g / m ² of alkali-treated gelatin was applied as a subbing layer on the recording surface side and dried, and alkali-treated gelatin was used as a back layer on the back side. A layer having the following constitution was coated on the support obtained by coating and drying 3.9 g / m ² .
For coating, the coating solutions of the respective layers were simultaneously coated by the slide hopper method. After each coating solution is superposed on the support, it is cooled and set at about 0 to 5 ° C. for about 20 seconds and then set to 20 to 50.
Ink jet recording sheet 1 was obtained by rapid drying with a wind in the range of ° C.

First layer (coating wet film thickness = 20 μm) Acid-treated gelatin 1.2 g Surfactant-1 0.004 g Second layer (coating wet film thickness = 100 μm) Phenylcarbamoylated gelatin * ¹ / polyvinyl alcohol * ² 6/4 (weight ratio) Xg Polymer latex particles (A) Yg Surfactant-2 0.002 g X + Y = 20 g Third layer (wet coating thickness = 18 μm) Phenylcarbamoylated gelatin * ¹ 1.0 g Polyvinyl alcohol * ² 1.5 g Surfactant-3 0.03 g * ¹ : Amino group blocking rate 80% * ² : Polymerization degree 300, saponification degree 88 mol% (PVA203: manufactured by Kuraray Co., Ltd.) Polymer latex particles (A): Styrene- Butadiene latex (solid content 50%: butadiene / styrene / acrylic acid = 58/40/2 monomer ratio is wt%)

[0042]

Embedded image

Inkjet recording sheet 2 was prepared by changing the addition amount Xg of phenylcarbamoylated gelatin / polyvinyl alcohol and the addition amount Yg of polymer latex particles (A) in the second layer of inkjet recording sheet 1 as shown in Table 1. ~ 6 were produced.

<Evaluation of Inkjet Recording Sheet> Using the obtained inkjet recording sheet, evaluation patterns were printed and evaluated for the following items using an inkjet printer BJC-600S manufactured by Canon Inc.

(1) Ink absorbency After leaving a recording paper on which three colors of yellow, magenta and cyan are recorded for 20 seconds at room temperature (20 ° C., 50% RH), each ink jet recording sheet is formed on the recorded image surface. Overlay the back side of the and apply a load of 5g per 10cm ² 3
It was judged whether or not the ink adhered to the recording surface on the opposite side when held for 0 seconds.

○ No adhesion × Clear adhesion △ Adhesion in a trace state (2) Gloss After printing, after being stored for one day and one night, and completely dried, the surface gloss is variable angle gloss manufactured by Nippon Denshoku Industries Co., Ltd. Degree meter (VGS-10
01DP).

(3) Blocking Ink jet recording sheets cut into 10 cm squares were conditioned at 23 ° C. and 80% RH for 24 hours, and then 5 sheets were superposed so that the ink receiving surface and the back surface face each other.
An average level of blocking between recording sheets after a load of kg was applied and storage for one week at 40 ° C. and 80% RH was judged according to the following criteria.

◎ Light peeling ○ Peeling off with a slight force △ Peeling with a noise, but no film peeling or film breakage × Complete sticking, film peeling or film breakage occurs when peeling (4) Curl 23 ° C After being left for 48 hours in an environment of 20% RH, 23% and 80% RH, curl heights at four corners of 10 cm × 10 cm were measured.

Table 1 shows the results of the above evaluation items.

[0050]

[Table 1]

As is clear from the results of Table 1, the inkjet recording sheets 1 to 4 of the present invention have improved blocking while maintaining good ink absorbency and glossiness, and are generally good. I understand. However, it can be seen that the ink jet recording sheet 5 of the comparative example has an excessive amount of polymer latex particles added, and gloss and blocking are deteriorated, and the ink jet recording sheet 6 is deteriorated in ink absorbability. The curl was within the practical range.

Example 2 Ink jet recording sheets 7 to 13 were prepared in the same manner as the ink jet recording sheet 2 of Example 1 except that the polymer latex particles contained in the second hydrophilic binder layer were changed to the following. Incidentally, the monomer amount ratio of the polymer latex particles represents% by weight.

-Recording sheet 7-Polymer latex (B) Styrene-butadiene latex (solid content 50%: butadiene / styrene / acrylic acid = 40/58/2) -Recording sheet 8-Polymer latex (C) Polyacrylate latex ( Solid content 30%: Styrene / glycidyl methacrylate / butyl acrylate = 20/40/40) -Recording sheet 9-Polymer latex (D) Polyurethane latex (polyethylene terephthalate-based polyol: solid content 3
0%)-Recording sheet 10-Polymer latex (E) Water-dispersed polyester (manufactured by Eastman Kodak: WD size, solid content 30%)-Recording sheet 11-Except for changing the first layer and the second layer to the following. The same structure as the recording sheet 7.

First layer (wet coating thickness = 20 μm) Acid-treated gelatin 1.2 g Polymer latex (B) 2.4 g Surfactant-1 0.004 g Second layer (wetting coating thickness = 100 μm) Phenylcarbamoylation Gelatin * ¹ 6.0 g Polyvinyl alcohol * ² 4.0 g Surfactant-2 0.002 g-Recording sheet 12-Same configuration as recording sheet 7 except that the second and third layers were changed to the following.

Second layer (wet coating thickness = 100 μm) Phenylcarbamoylated gelatin * ¹ 6.0 g Polyvinyl alcohol * ² 4.0 g Surfactant-2 0.002 g Third layer (wetting coating thickness = 18 μm) Phenyl Carbamoylated gelatin * ¹ 1.0 g Polyvinyl alcohol * ² 1.5 g Polymer latex (B) 4.0 g Surfactant-3 0.03 g-Recording sheet 13-Phenylcarbamoylated gelatin / polyvinyl alcohol weight ratio 7/3 The configuration is the same as that of the recording sheet 8 except that it is changed to.

* ¹ : Amino group blocking rate 80% * ² : Polymerization degree 300, saponification degree 88 mol% (PVA20
3: manufactured by Kuraray Co., Ltd. The ink jet recording sheets 7 to 13 thus obtained were used in Example 1
The evaluation was performed in the same manner as described above. Table 2 shows the results.

[0057]

[Table 2]

As is clear from the results shown in Table 2, the ink jet recording sheets 7 to 11 and 13 of the present invention are generally good. However, it is understood that the ink jet recording sheet 11 is slightly inferior in ink absorbency, and it is preferable that the polymer latex particles are contained in the layer adjacent to the outermost layer. Further, the ink jet recording sheet 13 had good ink absorbency, glossiness and blocking property, but the curl at 23 ° C. and 20% RH was slightly larger than the others (the ink jet recording sheet 13 was made of polyvinyl alcohol). Weight is 4 of total hydrophilic binder
Less than 0%).

[0059]

As described above, according to the present invention, there is provided an ink jet recording sheet which has a vivid surface gloss, good ink absorbability, which is difficult to achieve by a conventional ink jet recording sheet, has less curl, and is less likely to cause blocking. can do. It is particularly suitable for forming a full-color image.

In this embodiment, the case of using an opaque and glossy paper support has been described. However, by using a translucent support, a recorded image can be displayed on a screen or the like by an optical device such as a slide or an OHP. It is possible to provide an ink jet recording sheet suitable for use in observation by projection of, a color separation plate when producing a positive plate for color printing, or a use of transmission of CMF or the like used in a color display such as liquid crystal.

Although the case where the recording sheet of the present invention is mainly used in the inkjet system has been described, it is suitable for recording by a recording device such as a writing instrument or a pen plotter which uses an aqueous ink, in addition to the inkjet system. Available.

Claims (4)

[Claims] 1. From 2 to 5 parts by weight of the hydrophilic binder
An inkjet recording sheet comprising a hydrophilic binder layer having 8 times the weight of polymer latex particles as a lower layer and at least one hydrophilic binder layer provided on a support. 2. The ink jet recording sheet according to claim 1, wherein the hydrophilic binder layer having the polymer latex particles is provided adjacent to the outermost hydrophilic binder layer. 3. The inkjet recording sheet according to claim 1, wherein the hydrophilic binder is a binder capable of reversibly converting into a sol-gel. 4. The inkjet recording according to claim 1, wherein 40% by weight or more of the total amount of the binder contained in the total hydrophilic binder layer on the support is polyvinyl alcohol. Sheet.