JP2003072231A - Ink jet recording sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording sheet, in which the discoloration in the long term storage of an ink jet recording sheet printed in full colors, especially the discoloration due to the fading under the condition that a phthalocyanine-based dye is employed as the dye for a cyan ink are remarkably decreased. SOLUTION: In the ink jet recording sheet, in which compounds represented by general formula (1): HO3 S-R1 -((S)n-R2 )p-SO3 H and general formula (2): R3 -((S)m-R4 )q-SO3 H, (wherein, R1 , R2 and R4 are each a 1-12C alkylene group or phenylene group; R3 is a 1-12C alkyl group or phenyl group; n and m are each an integer of 1 or 2; and p and q are each an integer of 1 to 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention maintains a feature that when a full-color image is printed using a liquid ink, particularly a water-based ink, in an ink jet recording sheet, the image printing density is high and the ink absorbability is excellent. While
The present invention relates to an inkjet recording sheet that does not undergo discoloration during long-term storage, which is a drawback of conventional inkjet recording sheets.

[0002]

2. Description of the Related Art An ink jet recording system in which a liquid ink such as water-based or oil-based ink is ejected from a fine nozzle onto a recording medium to form an image, has a low noise during recording, is easy to color, and is capable of high-speed recording. Is possible,
Further, it is widely used in terminal printers, facsimiles, plotters, form printing, etc. because it is cheaper than other printing devices. On the other hand, with the rapid spread of printers, high definition and high speed, and the advent of digital cameras, advanced characteristics have come to be demanded on the recording medium side as well. In other words, there is a strong demand for the realization of a recording material which is excellent in absorption, recording density, water resistance, and storage stability and which has image quality and storage stability comparable to those of silver salt photography.

In order to meet such demands, many proposals have been made regarding a sheet having an ink receiving layer mainly composed of a pigment and an adhesive on a support. For example, a coating layer composed of amorphous silica and a polymer binder (JP-A-55-51583, JP-A-57-157786 and JP-A-62-158084), a coating layer having an ink adsorbing pigment such as zeolite ( JP-A-56-14417
No. 2), a coating layer composed of finely divided silicic acid and a water-soluble resin (JP-A-56-148583), and a coating layer containing a porous cationic alumina hydrate (JP-A-60-2).
No. 32990) is proposed on the support.

Further, from the viewpoint of improving the water resistance of printing, a cationic polymer (JP-A-56-84992, JP-A-6-84992, JP-A-6-84992) is used.
No. 0-49990, No. 61-125878), a basic latex (Japanese Patent Laid-Open No. 57-36692) and the like have been proposed in the ink receiving layer.

Further, from the viewpoint of improving the storability of printing, a method of adding at least one of metal oxides such as phosphotungstic acid, phosphomolybdic acid and chromic chloride, metal chlorides or tannic acid (special characteristics Kaisho 57-8798
7), a method of adding antioxidants such as hindered phenols (JP-A-57-74192), and a method of adding hindered amines (JP-A-61-1465).
91), a benzophenone-based, benzotriazole-based, phenylsalicylic acid-based, or other ultraviolet absorber (JP-A-57-74193 and 57-879).
88, 63-222885), a method for adding a thiourea compound (JP-A-61-163886), and a specific mercapto compound such as 2-mercaptobenzothiazole and 2-mercaptobenzimidazole. (JP-A-61-177279), a method of adding a dithiocarbamate, a thiuram salt, a thiocyanate or a thiocyanate (JP-A-7-3148).
No. 82) has been proposed.

However, the full-color ink jet recorded image formed by using these techniques is not yet affected by discoloration during long-term storage, especially when a phthalocyanine dye is used as a dye for cyan ink, discoloration due to its fading. It was insufficient.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is to achieve full color printing on an ink jet recording sheet.
Discoloration during long-term storage, which has been a drawback of conventional inkjet recording sheets, particularly when a phthalocyanine dye is used as a dye for cyan ink, it is possible to provide an inkjet recording sheet with significantly reduced discoloration due to its fading. is there.

[0008]

_Wherein each R _1, R 2, _{R 4 is} an alkylene group or a phenylene group _C 1 ~C _{12, R 3 is} an alkyl group or a phenyl group _C 1 ~C _12, n, m are each 1 or 2, p and q each represent an integer of 1 to 4. ]

[2] At least one kind selected from the homopolymer of the diallylamine compound represented by the general formula (3) and the copolymer of the ethylenically unsaturated compound copolymerizable with the general formula (3) is contained. An ink jet recording sheet according to [1], characterized in that

[Chemical 2] [In the general formula (3), R ₅ and R ₆ each represent a hydrogen atom or a methyl group, R ₇ represents a hydrogen atom or a C _{1 to} C ₄ alkyl group, and HX represents an acid. ]

[3] Description of [1] or [2], wherein the compound represented by the general formula (1) is 2,2'-thiobis (ethanesulfonic acid) or 2,2'-dithiobis (ethanesulfonic acid). Inkjet recording sheet. [4] The inkjet recording sheet according to any one of [1] to [3], in which a cast gloss layer is provided on the inkjet recording sheet. [5] The inkjet recording sheet according to any one of [1] to [3], wherein the inkjet recording sheet has a cast-treated ink receiving layer. [6] The inkjet recording sheet according to any one of [1] to [5], wherein the cyan dye used in the liquid ink is a phthalocyanine dye.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The inventors of the present invention, in an ink jet recording sheet for forming a recorded image using a liquid ink, include a compound represented by the general formula (1) and the general formula (2) in the recording sheet. In addition, by containing at least one selected from those salts, discoloration during long-term storage, which was a drawback of conventional inkjet recording sheets, when printed in full color on inkjet recording sheets, especially dyes for cyan ink As a result, they have found that when a phthalocyanine-based dye is used, an ink jet recording sheet in which the discoloration due to the fading is significantly reduced can be obtained, and the present invention has been completed.

HO ₃ S-R ₁ -((S) n-R ₂ ) p-SO ₃ H (1) R ₃ -((S) m-R ₄ ) q-SO ₃ H (2) [wherein , R ₁ , R ₂ , and R ₄ are each a C _{1 to} C ₁₂ alkylene group or a phenylene group, and R ₃ is a C _{1 to} C group.
₁₂ alkyl groups or phenyl groups, n and m each represent 1 or 2, and p and q each represent an integer of 1 to 4. ]

Specific examples of the compound represented by the general formula (1) or (2) include thiobis (methanesulfonic acid), dithiobis (methanesulfonic acid) and 2,2'-.
Thiobis (ethanesulfonic acid), 2,2'-dithiobis (ethanesulfonic acid), 3,3'-thiobis (propanesulfonic acid), 3,3'-dithiobis (propanesulfonic acid), 4,4'-thiobis ( Butanesulfonic acid),
4,4'-dithiobis (butanesulfonic acid), 6,6'-
Thiobis (hexanesulfonic acid), 6,6'-dithiobis (hexanesulfonic acid), 8,8'-thiobis (octanesulfonic acid), 8,8'-dithiobis (octanesulfonic acid), 10,10'-thiobis ( Decanesulfonic acid), 10,10'-dithiobis (decanesulfonic acid), 12,12'-dithiobis (laurylsulfonic acid), 4,4'-thiobis (laurylsulfonic acid),
4,4'-dithiobis (benzenesulfonic acid), 3,3 '
-Thiobis (benzenesulfonic acid), 2,2'-thiobis (benzenesulfonic acid), 1,2-bis (2-sulfoethylthio) ethane, 2,2'-thiobis (2-ethylthioethanesulfonic acid), 2-Methylthioethanesulfonic acid, 2-ethylthioethanesulfonic acid, 2-ethyldithioethanesulfonic acid, 2-isopropylthioethanesulfonic acid, 2-octylthioethanesulfonic acid, 2-laurylthioethanesulfonic acid, 4-methylthio Butanesulfonic acid, 2-phenylthioethanesulfonic acid, 4-methylthiobenzenesulfonic acid, 3-methylthiobenzenesulfonic acid, 2-methylthiobenzenesulfonic acid, 4-
Ethylthiobenzenesulfonic acid, 4-phenylthiobenzenesulfonic acid, 3,6-dithiooctanesulfonic acid,
3,6,9-trithioundecane sulfonic acid and the like can be mentioned.

Among these compounds, 2,2'-thiobis (ethanesulfonic acid) and 2,2'-dithiobis (ethanesulfonic acid) are particularly preferable because they have a particularly high discoloration preventing effect.

The ions forming a salt with the general formulas (1) and (2) include, for example, sodium, potassium,
Examples thereof include magnesium, calcium, zinc, ammonium and organic amines.

In the present invention, the general formula (3) is further added.
By containing at least one selected from the homopolymer of the diallylamine compound represented by and the copolymer of the general formula (3) and the ethylenically unsaturated compound copolymerizable with the general formula (3), a high synergistic effect for preventing discoloration can be obtained. Is recognized.

[0017]

[Chemical 3]

[In the general formula (3), R ₅ and R ₆ are each a hydrogen atom or a methyl group, and R ₇ is a hydrogen atom or C ₁
An alkyl group -C _4, HX represents an acid. ] R ₇ is preferably a hydrogen atom.

The acid represented by HX of the general formula (3) may be either an inorganic acid or an organic acid. As the inorganic acid, hydrochloric acid,
Sulfuric acid, nitric acid, phosphoric acid, pyrophosphoric acid, metaphosphoric acid, and the like, and organic acids include formic acid, acetic acid, propionic acid, methanesulfonic acid, p-toluenesulfonic acid, and the like. Among these acids, hydrochloric acid and sulfuric acid are particularly effective in preventing discoloration and are preferably used.

The homopolymer and copolymer of the diallylamine compound represented by the general formula (3) include, for example, polydiallylamine hydrochloride, polydiallylamine sulfate, polydiallylamine phosphate, polydiallylamine acetate and polydiallylamine. Of propionate,
Methanesulfonic acid salt of polydiallylamine, polydiallylmethylamine hydrochloride, polydiallylmethylamine sulfate, polydiallylethylamine hydrochloride, polydiallylethylamine sulfate, polydiallyl-n-propylamine hydrochloride, polydiallyl-n-butylamine hydrochloride , Diallylamine hydrochloride / acrylamide copolymer, diallylamine sulfate / acrylamide copolymer, diallylamine phosphate / acrylamide copolymer, diallylmethylamine hydrochloride / acrylamide copolymer, diallylmethylamine sulfate / acrylamide copolymer Coupling, diallylmethylamine phosphate / acrylamide copolymer, diallylethylamine hydrochloride / acrylamide copolymer,
Examples thereof include diallylamine hydrochloride / sulfur dioxide copolymer, diallylamine sulfate / sulfur dioxide copolymer, diallylmethylamine hydrochloride / sulfur dioxide copolymer, diallylethylamine hydrochloride / sulfur dioxide copolymer and the like. By using these, not only the water resistance is improved, but there is a synergistic effect in preventing discoloration.

A full-color ink jet recorded image is discolored during long-term storage, and particularly when a phthalocyanine dye is used as a dye for cyan ink, the discoloration due to its fading is a significant factor because the cyan dye having a phthalocyanine skeleton is a gas in the air. Especially, it is considered that it is easily and selectively oxidized by a gas having a strong oxidizing power such as ozone.

The reason why the compounds represented by the general formulas (1) and (2) found this time were particularly effective in preventing discoloration is not clear, but the general formula (1) or the general formula (2) is used. It is considered that since the compound represented by (4) itself is easily oxidized by a gas having a strong oxidizing power such as ozone, it is oxidized before the cyan dye is oxidized, and as a result, the cyan dye is prevented from being oxidized.

Further, since the compound produced by oxidizing the compound represented by the general formula (1) or (2) is colorless, it is also a great feature that it does not cause problems such as yellowing of the background.

The content of the compound represented by the general formula (1) or the general formula (2) in the ink jet recording sheet is about 0.1 to 4 g / m ² , preferably about 0.
It is about ² to ² g / m ² . Incidentally, if it is less than 0.1 g / m ² , the effect of improving the preservability may be insufficient,
If it is more than 4 g / m ² , the image quality may be deteriorated.

When the homopolymer and copolymer of the compound represented by the general formula (3) are used in combination, the content thereof is generally 1 to 100 parts by weight, preferably 5 to 50 parts by weight, based on 100 parts by weight of the pigment. Adjusted in range. If the blending amount is small, it is difficult to sufficiently obtain the effects of improving print water resistance, print density, and the like, and if the blending amount is large, the print density may be decreased, or image bleeding may occur.

As a method for preparing an ink jet recording sheet containing the compounds represented by the above general formulas (1) and (2) and salts thereof, for example, a compound specific to the present invention can be prepared by a size press in a papermaking process. A method of coating or impregnating a base paper with a coating liquid containing the ink, an ink absorbing pigment,
Adhesive, coating liquid for ink receiving layer obtained by mixing the above specific compounds is applied to a support such as paper (acidic paper, neutral paper), synthetic paper, plastic film, non-woven fabric using a coating machine. A method of drying to form an ink receiving layer, a method of applying a coating liquid containing the above-mentioned specific compound onto an ink receiving layer composed of a pigment, an adhesive, and more preferably a specific polymer containing the general formula (3), etc. Can be mentioned.

Among them, the method of incorporating the compounds represented by the general formulas (1) and (2) in the ink receiving layer is more effective in preventing discoloration of an image, and is therefore preferable.

The compounds represented by the general formulas (1) and (2) and salts thereof are used as an aqueous solution when they are water-soluble, and as a dispersion medium when they are water-insoluble. It is used after finely pulverized with a stirrer / pulverizer such as a lighter, sand mill, colloid mill.

As the support of the ink jet recording paper, paper (acidic paper, neutral paper), synthetic paper, plastic film, non-woven fabric or plastic film laminated with coated paper or high quality paper via an adhesive, Alternatively, a paper laminated with plastic is used. Examples of such plastic film include films of polyester, polypropylene, nylon and the like.

Examples of pigments contained in the ink receiving layer include zeolite, light calcium carbonate, heavy calcium carbonate, magnesium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium oxide, zinc oxide,
Zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, amorphous silica, aluminum hydroxide, alumina,
Alumina hydrate, lithopone, urea-formalin resin filler and the like can be mentioned. These may be used alone or in combination of two or more.

Among these, amorphous silica, alumina and alumina hydrate are preferably used because they have excellent ink absorbency.

The amount of pigment used in the ink receiving layer is
20 to 90% by mass based on the solid content of the ink receiving layer,
It is preferably about 30 to 80% by mass. If it exceeds 90% by mass, the coating strength of the ink receiving layer may decrease, and if it is less than 20% by mass, the ink absorbency may decrease, resulting in insufficient ink drying property after recording. The image quality may deteriorate.

In the present invention, it is also possible to use as the cationic polymer, a polymer which dissociates when it is dissolved or emulsified in water and exhibits a cationic property. As such a cationic polymer, for example,
Polydiallyldimethylammonium chloride, diallyldimethylammonium chloride / acrylamide copolymer, diallyldimethylammonium chloride / sulfur dioxide copolymer, polyallylamine hydrochloride, allylamine hydrochloride / diallylamine hydrochloride copolymer, N-vinylacrylamidine hydrochloride -Acrylamido copolymer, dialkylamine-epichlorohydrin heavy compound,
Polyamide polyamine epichlorohydrin polycondensate, dicyandiamide / formalin polycondensate, polyethylene polyamine / dicyandiamide polycondensate, polyethyleneimine hydrochloride, poly (meth) acryloyloxyalkyldialkylamine hydrochloride, (meth) acryloyloxyalkyldialkylamine Hydrochloride / acrylamide copolymer, poly (meth) acryloyloxyalkyltrialkylammonium chloride, (meth) acryloyloxyalkyltrialkylammonium chloride
Acrylamide copolymer, poly (meth) acrylamidealkyldialkylamine hydrochloride, (meth) acrylamidealkyldialkylamine hydrochloride / acrylamide copolymer, poly (meth) acrylamidealkyltrialkylammonium chloride, (meth) acrylamidealkyltrialkylammonium Examples thereof include chloride / acrylamide copolymers.

In the ink receiving layer, as an adhesive, for example, starch derivatives such as oxidized starch and etherified starch, cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose, casein, gelatin, soybean protein,
Fully (partially) saponified polyvinyl alcohol, silicon-modified polyvinyl alcohol, acetoacetyl group-modified polyvinyl alcohol, styrene-maleic anhydride copolymer salt, styrene-butadiene latex, acrylic latex, polyester polyurethane latex, vinyl acetate A water-based adhesive such as latex or an organic solvent-soluble resin such as polymethylmethacrylate, polyurethane resin, unsaturated polyester resin, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral or alkyd resin may be used alone or in combination. To be These adhesives are generally 1 to 100 parts by weight of the pigment.
It is used in an amount of about 200 parts by mass, preferably about 10 to 100 parts by mass.

Further, in the ink receiving layer, a pigment dispersant,
Thickener, cross-linking agent, fluidity modifier, defoaming agent, foam suppressor, release agent, foaming agent, penetrant, coloring dye, coloring pigment, fluorescent whitening agent, preservative, anti-bacterial agent, water resistance. Agents and the like can be added as appropriate.

For the ink receiving layer, the coating liquid for the ink receiving layer is applied by a bar coater, a blade coater, an air knife coater,
It is formed by applying a coating method such as a gravure coater, a die coater, and a curtain coater on at least one surface of the support so that the coating amount after drying is about ² to 30 g / m ² . Incidentally, if the coating amount is less than 2 g / m ² , the recording image quality may deteriorate, and if it is more than 30 g / m ² , the coating strength may decrease.

After forming the ink receiving layer, it is also possible to provide surface smoothness for the purpose of imparting high gloss, for example, by passing between roll nips under pressure with a super calender or gloss calender.

Further, an ink jet recording sheet having a higher surface gloss can be obtained by providing a gloss-developing layer on the ink receiving layer and subjecting it to a cast treatment, or by directly subjecting the ink receiving layer to a cast treatment. As a method of casting treatment, there are a wet method, a gelling method and a rewet method. In the wet method, while the gloss-developing layer coated on the base paper is in a wet state, the gloss-developing layer is pressed against the heated specular drum surface to perform a strong gloss finish. The gelling method is that while the gloss-developing layer coated on the base paper is in a wet state, the gloss-developing layer is brought into contact with the gelling agent bath, and the gelled gloss-developing layer is pressed against the heating drum surface. It is a high gloss finish. The rewet method is
The gloss-developing layer in a wet state is once dried, then again brought into contact with the wetting liquid, and then pressed against the surface of the heating drum to perform a strong gloss finish.

It is also possible to obtain a layer having excellent gloss by pressing a smooth PET film or the like on the recording layer in a wet state and then drying it. Further, it is of course possible to provide a protective layer on the back surface of the support, or to provide an intermediate layer (containing, for example, a pigment and an adhesive) between the support and the recording layer. Known techniques can be added.

The ink for forming a recorded image is a recording liquid composed of a colorant, a liquid medium, and other additives. In the case of water-based ink, examples of the colorant include various water-soluble dyes such as direct dyes, acid dyes, and reactive dyes.
The liquid medium of the water-based ink may be water alone or a combination of water and a water-soluble organic solvent. Examples of the water-soluble organic solvent include monohydric alcohols such as ethyl alcohol and isopropyl alcohol, polyhydric alcohols such as ethylene glycol, diethylene glycol, polyethylene glycol and glycerin, triethylene glycol monomethyl ether, triethylin, triethylene glycol monomethyl ether and triethylene. Examples thereof include lower alkyl ethers of polyhydric alcohols such as glycol monoethyl ether. Further, examples of the additive include a pH adjusting agent, a sequestering agent, an antifungal agent, a viscosity adjusting agent, a surface tension adjusting agent, a surfactant, and a rust preventive agent.

[0041]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In addition, "part" and "%" in an example show a mass part and mass%, respectively, unless there is particular notice.

Example 1 (Preparation of coating liquid A for ink receiving layer) Synthetic amorphous silica (trade name: Fineseal X60, manufactured by Tokuyama Corporation) 100
Part, silicon modified polyvinyl alcohol (trade name: R11
30 parts, 250 parts of 10% aqueous solution of Kuraray Co., Ltd., 40% of diallylamine hydrochloride / acrylamide copolymer (trade name: Sumirez Resin 1001, manufactured by Sumitomo Chemical Co., Ltd.)
75 parts of an aqueous solution, 100 parts of a 10% aqueous solution of 2,2'-dithiobis (sodium ethanesulfonate), a small amount of an antifoaming agent, a dispersant and water, and a coating liquid A for an ink receiving layer having a solid content concentration of 15% were obtained. It was

(Preparation of Inkjet Recording Sheet) 6
After providing the ink-receiving layer by coating and drying a wire bar such that the 12 g / m ² coating liquid A for ink-receiving layer in solid content quality paper of 5 g / m ^2, the ink jet Super calendering A recording sheet was created.

Examples 2 to 11 An ink jet recording sheet was prepared in the same manner as in Example 1 except that the following compounds were used instead of 2,2'-dithiobis (sodium ethanesulfonate). Created. Example 2: 2,2'-thiobis (sodium ethanesulfonate) Example 3: 4,4'-thiobis (sodium butanesulfonate) Example 4: 4,4'-thiobis (sodium benzenesulfonate) Example 5: Sodium 2-methylthioethanesulfonate Example 6: Sodium 4-methylthiobenzenesulfonate Example 7: 2,2'-Dithiobis (ethanesulfonic acid) Example 8: 2,2'-Dithiobis (ammonium ethanesulfonate) ) Example 9: 2,2'-Dithiobis (ethanesulfonic acid)
Example 10: Magnesium salt of 2,2'-dithiobis (ethanesulfonic acid) Example 11: Zinc salt of 2,2'-dithiobis (ethanesulfonic acid)

Example 12 In Example 1, a diallylamine hydrochloride / acrylamide copolymer (trade name: Sumirez Resin 1001,
In the same manner as in Example 1 except that polydimethyldiallylammonium chloride / acrylamide copolymer (trade name: PAS-J-81, manufactured by Nitto Boseki Co., Ltd.) was used instead of Sumitomo Chemical Co., Ltd. To prepare an ink jet recording sheet.

Example 13 (Preparation of coating liquid B for ink receiving layer) Synthetic amorphous silica (trade name: Fineseal X60, manufactured by Tokuyama Corp.) 100
Part, silicon modified polyvinyl alcohol (trade name: R11
30 parts, 250 parts of 10% aqueous solution of Kuraray Co., Ltd., 40% of diallylamine hydrochloride / acrylamide copolymer (trade name: Sumirez Resin 1001, manufactured by Sumitomo Chemical Co., Ltd.)
A coating liquid B for an ink receiving layer having a solid content concentration of 15%, which comprises 75 parts of an aqueous solution, a small amount of a defoaming agent, a dispersant, and water, was obtained.

(Preparation of Inkjet Recording Sheet) 6
After providing the ink-receiving layer was applied and dried using a wire bar such that the 12 g / m ² coating liquid B for ink-receiving layer in solid content quality paper of 5 g / m ^2, 2,2'-dithiobis ( A 5% aqueous solution of sodium ethanesulfonate) was applied and dried with a wire bar so that the solid content was 1.0 g / m ^2, and subjected to a super calender treatment to prepare an inkjet recording sheet.

Example 14 (Preparation of coating liquid for gloss developing layer) A composite of a styrene-2-ethylhexyl acrylate copolymer and colloidal silica having a glass transition point of 75 ° C. (the copolymer and the colloidal silica are in a weight ratio of 40). : 60) 100 parts, 5 parts of alkyl vinyl ether / maleic acid derivative copolymer as a thickening / dispersing agent, and 3 parts of lecithin as a releasing agent.
A coating solution for 0% gloss development layer was obtained. (Preparation of ink-jet recording sheet) The coating liquid for the ink-receiving layer of Example 1 was added to a high-quality paper of 65 g / m ^{2 in} a solid content of 1
After coating and drying with a wire bar so as to be ² g / m ² and providing an ink receiving layer, the coating liquid for the gloss-developing layer was applied, and then immediately pressed against a mirror surface drum whose surface temperature was 85 ° C.,
After drying, they were released from the mold to prepare a gloss type inkjet recording sheet having a gloss layer. The coating amount of the glossy layer at this time was 8 g / m ² in terms of solid content.

Comparative Example 1 An ink jet recording sheet was prepared in the same manner as in Example 1 except that 2,2'-dithiobis (sodium ethanesulfonate) was not used.

Comparative Example 2 In Example 1, instead of 100 parts of a 10% aqueous solution of 2,2′-dithiobis (sodium ethanesulfonate), 3,3′-thiodipropionic acid was obtained as follows. An inkjet recording sheet was prepared in the same manner as in Example 1 except that 50 parts of 20% dilauryl dispersion was used. (Preparation of Dispersion of Dilauryl 3,3′-thiodipropionate) Dilauryl 100 3,3′-thiodipropionate
Part, sulfo group-modified polyvinyl alcohol (trade name: Gocelan L-3266, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) 5 parts, a small amount of a surfactant, an antifoaming agent and water, and a solid content of 20%.
The average particle size of the composition was 0.5μ with a sand grinder.
The dispersion was obtained by pulverizing to m.

Comparative Example 3 In Comparative Example 2, 2,6-di-tert-butyl-p was used in place of dilauryl 3,3'-thiodipropionate.
-An inkjet recording sheet was prepared in the same manner except that cresol was used.

Comparative Example 4 Example 1 was repeated except that 2,2'-dithiobis (sodium ethanesulfonate) was not used in Example 14.
An ink jet recording sheet was prepared in the same manner as in 4.

With respect to the ink jet recording sheets obtained in the examples and comparative examples, solid prints of mixed black and cyan inks by cyan, magenta, and yellow color mixing and an image of ISO-400 (Epson ink jet printer PM-800C were used. High-definition color digital standard image data ISO / JIS-SCI
D ”, p13, image name: portrait, published by Japan Planning Association), the following evaluations were performed, and the results are shown in Table 1. A phthalocyanine dye is used as a cyan dye in PM-800C.

[Printing Density] The density of the solid printing portion of the mixed black and cyan inks obtained by mixing cyan, magenta and yellow colors is measured by a Macbeth densitometer (type: RD-914,
It was measured using a Macbeth).

[Ozone Resistance] Ozone resistance highly correlated with long-term storage stability was evaluated. Solid-color printing of mixed black and cyan inks with cyan, magenta, and yellow mixed colors, and ISO-400 images, ozone concentration 10p
It was left in a pm container for 12 hours. In the case of solid printing, the Macbeth density after the test was measured, and the image residual rate was calculated by the following formula. On the other hand, in the case of an image, the degree of discoloration was visually observed and evaluated. Image residual rate (%) = [(density after processing) / (density before processing)] x 100 (image ozone resistance evaluation standard) ◎: No discoloration observed ○: Some discoloration observed, but practical No problem on top x: Discoloration is remarkable and there is a problem in practical use

[0056]

[Table 1]

[0057]

As is apparent from Table 1, the ink jet recording sheet of the present invention is a recording sheet which exhibits very little discoloration of images even when exposed to ozone gas and has excellent long-term storage stability. .

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Claims (6)

[Claims] 1. An ink jet recording sheet for forming a recorded image using a liquid ink, wherein the recording sheet is selected from the group consisting of compounds represented by the general formulas (1) and (2) and salts thereof. An ink jet recording sheet comprising at least one of the following: _{HO 3 S-R 1 - (} (S) n-R 2) p-SO 3 H (1) R 3 - ((S) m-R 4) q-SO 3 H (2) [In the formula, _{R 1} , R ₂ and R ₄ are each a C _{1 to} C ₁₂ alkylene group or a phenylene group, and R ₃ is a C ₁ to C ₁ group.
₁₂ alkyl groups or phenyl groups, n and m each represent 1 or 2, and p and q each represent an integer of 1 to 4. ] 2. A homopolymer of a diallylamine compound represented by the general formula (3) and at least one selected from a copolymer of an ethylenically unsaturated compound copolymerizable with the general formula (3). The inkjet recording sheet according to claim 1, wherein the sheet is an inkjet recording sheet. [Chemical 1] [In the general formula (3), R ₅ and R ₆ each represent a hydrogen atom or a methyl group, R ₇ represents a hydrogen atom or a C _{1 to} C ₄ alkyl group, and HX represents an acid. ] 3. A compound represented by the general formula (1) is 2,
The inkjet recording sheet according to claim 1, which is 2'-thiobis (ethanesulfonic acid) or 2,2'-dithiobis (ethanesulfonic acid). 4. The ink jet recording sheet according to claim 1, wherein a cast gloss layer is provided on the ink jet recording sheet. 5. The ink jet recording sheet according to claim 1, which has a cast-treated ink receiving layer.
Ink jet recording sheet according to the item. 6. The ink jet recording sheet according to claim 1, wherein the cyan dye used in the liquid ink is a phthalocyanine dye.