JP2006192640A - Inkjet recording material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording material, the surface of which has low brightness and no color spot, which has the texture of a non-coated paper and can cope with various surface hues. <P>SOLUTION: In the inkjet recording material, on at least one side of a base paper of which a coating liquid including a coloring agent and an ink fixing agent is applied/colored, the coating liquid includes a basic polyaluminum hydroxide. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ink jet recording material having a surface hue and texture similar to those of paper with low whiteness (such as weekly magazines, magazines, and newspapers).

  The ink jet recording system records images, characters, and the like by causing micro droplets of ink to fly and adhere to a recording sheet such as paper according to various operating principles. Inkjet printers and plotters have rapidly become popular in recent years in various applications as hard copy creation devices for image information such as letters and various graphics created by computers. In particular, color images formed by the multi-color ink jet method can be recorded inferior to multi-color printing by the plate making method and printing by the color photographic method, and in applications where the number of copies is small. Are being widely applied because they are less expensive than printing and photographic techniques.

  Furthermore, with the diversification of uses, it is increasingly used for large-format posters, POP art, and drafting. In these applications, since the high sharpness of the ink jet is utilized and the color is excellent, a good image can be obtained and the advertising effect is great. Application to these is because it is possible to easily obtain images with excellent image reproducibility and color reproducibility such as sharpness and color at the personal computer level, and this is also the reason for using a lot of inkjet recording paper. .

  Inkjet recording systems have come to be used for color proofing of publications. Proofreading a color page of a publication is a test print, collated with the manuscript, corrects the error or inappropriateness, and confirms the color of the printed matter, the effect of color printing, etc. This is a process to check whether it is completed. However, when calibration is performed using an actual printing machine, a large amount of printing ink and printing paper are consumed, and a long time is required. For this reason, it has been considered that the color tone is adjusted in advance using a simple ink jet recording type printer.

  In recent years, colorization of paper has been progressing even in low-priced printed materials using low-whiteness paper (including paper with used paper) such as weekly magazines, magazines, newspapers, etc., and color proofing by the ink jet method has been introduced. . Recently, a dedicated machine for proofreading printing, which is integrated with a printer and a color management system, is also on the market. Furthermore, an on-demand printing type issuance system that applies the inkjet method in order to reduce the cost of printing and to respond to detailed requests by changing the contents of the paper as needed. Has also been proposed. The materials used for these are required to be the same or as close as possible to the current paper. This is because the image of the current paper is already fixed, and the same texture and texture are required.

  In order to satisfy such requirements, an ink jet recording material has been proposed in which an ink receiving layer containing a colorant is provided on a support and the hue is approximated to low whiteness paper such as a weekly magazine, magazine, or newspaper. . According to this method, the hue of the ink jet recording material can be approximated, but since the ink receiving layer contains a pigment, the surface texture is different from that of weekly magazines, magazines, newspapers, etc. is there. (See Patent Document 1)

On the other hand, there has been proposed an ink jet recording paper for newspaper printing, which contains 50% or more of mechanical pulp and / or deinked waste paper pulp and contains a water-soluble polyvalent metal salt without providing an ink receiving layer. Since this ink jet recording paper does not have an ink receiving layer, the surface texture can be very close to that of weekly magazines, magazines, newspapers, etc., and good printability can be obtained by the action of the water-soluble polyvalent metal salt. In addition, the surface hue can be controlled by the blending amount of mechanical pulp and / or deinked waste paper pulp and the addition of colorant. There are problems such as inefficiency in producing small lots, and it is difficult to adjust the surface hue to the target hue very accurately, and it is not sufficient for use on proof paper. Also, in the method of adjusting the surface hue by applying a coating liquid containing a colorant to paper, there is no such problem, but when the coating liquid is applied, the penetration of the coating liquid into the base paper becomes uneven, Coloring tends to be non-uniform, especially when it is darkly colored, causing color spots and the appearance looks dirty. (See Patent Document 2)
JP 2000-318299 A JP 2003-326844 A

  An object of the present invention is to solve the above-mentioned problems and to provide an ink jet recording material having a low surface whiteness, no color spots, a texture of uncoated paper, and capable of dealing with various surface hues. In particular, weekly magazines, magazines, newspapers, and other papers that contain mechanical pulp and / or waste paper pulp, have a similar texture and surface hue to low-whiteness paper, have no surface hue unevenness, and can be printed well by the inkjet method An object of the present invention is to efficiently provide a sheet and an inkjet recording sheet for calibration.

  As a result of intensive research to achieve the above object, in an inkjet recording material in which a coating liquid containing a colorant and an ink fixing agent is applied and colored on at least one side of a base paper, a basic polywater is contained in the coating liquid. The present invention has been solved by an ink jet recording material characterized by containing aluminum oxide.

Lightness JIS Z8730 colored surface L ^* is preferably from 2.5 or more smaller該明index of the precolored raw paper L ^*.

  More preferably, the ink fixing agent is a metal salt of magnesium or calcium.

  More preferably, the base paper contains 20% by mass or more of mechanical pulp and / or waste paper pulp.

More preferably, the lightness index L ^* according to JIS Z8730 of the colored surface is 80 or more and 85 or less, and the color coordinate a ^* is −3.0 or more and 0 or less, and b ^* is 3.0 or more and 9.3 or less. .

  According to the present invention, weekly magazines, magazines, newspapers, etc., such as mechanical pulp and / or wastepaper pulp mechanical pulp, can approximate the texture of paper with low whiteness, and can adjust the hue of the surface without colored spots. In addition, it is possible to obtain a printing paper that can be printed favorably by the ink jet method and an ink jet recording paper for calibration.

The ink jet recording material of the present invention will be described below. Hereinafter, the surface hue is represented by the lightness index L ^* and color coordinates a ^* and b ^* according to JIS Z8730.

  The ink jet recording material of the present invention is obtained by applying a coating liquid containing a colorant and an ink fixing agent to at least one side of a base paper and coloring the surface of the base paper. Basic polyaluminum hydroxide is added to the coating liquid. contains.

Lightness JIS Z8730 colored surface L ^* is, when colored to be less before該明degree of the base paper index L ^* than 2.5 or more coloring, preferably obtained higher effect of the basic polyaluminum hydroxide.

  As the colorant used in the ink jet recording material of the present invention, a dye-based colorant and a pigment-based colorant can be used, but it is particularly preferable to use a pigment-based colorant from the viewpoint of storage stability of the recording paper hue. preferable.

  Specific examples of the colorant include, for example, azo compounds (dithizone, formazan), quinone series (naphthoquinone, anthraquinone, acridone, anthanthrone, indanthrene, pyrenedione, violanthrone), quinoneimine (azine, oxazine, thiazine), indigo dye ( Indirubin, oxyindigo, thioindigo), sulfur dyes, diphenylmethane, triphenylmethane (fluorane, fluorescein, rhodamine), ferrocene, fluorenone, fulgide, perylene, phenazine, phenothiazine, polyene (carotene, maleic acid derivative, pyrrolazone, stilbene, styryl) , Polymethine (cyanine, pyridinium, pyrylium, quinolinium, rhodanine), xanthene, alizarin, acridine, acridinone, carbosty Dye-based colorants such as leuco, coumarin, diphenylamine, quinacridone, quinophthalone, phenoxazine, phthaloperinone, porphine, chlorophyll, phthalocyanine, crown compound, squarylium, thiafulvalene, thiazole, nitro dye, nitroso dye, leuco dye after coloring, or Titanium black, titanium yellow, ultramarine, bitumen, cobalt blue, carbon black, iron black, zinc oxide, cobalt oxide, silicon oxide, aluminum hydroxide, azo pigment, azo lake pigment, phthalocyanine pigment, vat dye pigment, quinacridone Pigment, dioxazine pigment, starch, urea-formalin resin, synthetic resin particles such as melamine resin, pigment colorants such as silicone particles, and stilbene, distilbene, benzoxazole, coumarin , Imidazole, benzimidazole, can be cited fluorescent dyes such as pyrazoline, but is not limited thereto.

  These colorants can be used alone or in combination of two or more. The mixing ratio may be any ratio as long as color spots do not occur.

  Further, the concentration of the colorant is not particularly limited as long as a desired color can be obtained, but is usually used in an amount of 0.001 to 2% by mass based on the entire coating liquid.

  The coating liquid according to the present invention contains an ink fixing agent for the purpose of improving ink absorptivity and bleeding of heavy color portions and improving water resistance of image portions. As the ink fixing agent, various organic and inorganic compounds can be used.

  Specific examples of organic fixing agents include polydiallyldimethylammonium resins, polyethyleneimine resins, polyamine resins, polyamide resins, polyamide epichlorohydrin resins, polyamine epichlorohydrin resins, polyamide polyamine epichlorohydrin resins, polydiallylamine resins. And cationic polymer compounds such as dicyandiamide condensate, but are not limited thereto.

  Specific examples of the inorganic fixing agent include water-soluble polyvalent metal salts. If it is a water-soluble metal salt having a valence of 2 or more, it can be used without any problem. However, if this is a monovalent metal salt such as Na or K, it has a low effect on the ink, and in order to bring out the same effect as the polyvalent metal salt. Since it is necessary to use a large amount and as a result, the characteristics as an ink jet recording material are affected, it is not realistic.

  In addition, the water-soluble polyvalent metal salt applied in the present invention is at least one selected from Mg, Al, and Ca, which has low toxicity and is easy to handle compared to highly toxic metal salts such as Pb salt, Ni salt, and Co salt. It is preferable that the salt is a seed or more. These polyvalent metal salts may be used alone or in combination of two or more. In this case, different metal salts may be used, or a combination such as sulfate and chloride of the same metal may be used.

Furthermore, with respect to the amount required to satisfactorily develop the effect of the water-soluble polyvalent metal salt, the water-soluble polyvalent metal salt is applied at least 0.1 g / m ² per side of the inkjet recording material. The effect can be expressed by doing. In consideration of color developability, it is more preferable to apply 0.3 g / m ² or more. Here, if the metal salt is less than 0.1 g / m ² , the effect on the ink is weak, and a sufficient effect may not be obtained. Furthermore, when the metal salt is applied in an amount of more than 3 g / m ² , the colorant pigment aggregates on the surface of the coating layer when ink jet recording is performed using a pigment ink, resulting in a deterioration in ink absorbability and a decrease in print density. Therefore, the metal salt is most preferably applied in an amount of 0.3 g / m ² or more and 3 g / m ² or less.

The coating liquid according to the present invention contains basic polyaluminum hydroxide for the purpose of preventing colored spots caused by the colorant. The basic polyaluminum hydroxide compound has a main component represented by the following general formula 1, 2, or 3, for example, [Al ₆ (OH) ₁₅ ] ³⁺ , [Al ₈ (OH) ₂₀ ] ⁴⁺ , [ It is a water-soluble polyaluminum hydroxide that stably contains a basic and high-molecular polynuclear condensed ion such as Al ₁₃ (OH) ₃₄ ] ⁵⁺ , [Al ₂₁ (OH) ₆₀ ] ³⁺ , and the like.

[Al ₂ (OH) _n Cl _6-n ] _m where 0 <n <6 (1)
[Al (OH) ₃ ] _n AlCl ₃ ... General formula 2
Al _n (OH) _m Cl _(3n-m) where 0 <m <3n (general formula 3)

  These are water treatment agents from Taki Chemical Co., Ltd. under the name of polyaluminum chloride (PAC), from Asada Chemical Co., Ltd. under the name of polyaluminum hydroxide (Paho), and from Riken Green Co., Ltd. It is marketed under the name of Purachem WT and from other manufacturers for the same purpose, and various grades can be easily obtained.

With respect to the application amount necessary for satisfactorily expressing the effect of the basic polyaluminum hydroxide compound, the effect can be expressed by applying 0.01 g / m ² or more on one side of the inkjet recording material, In particular, a good effect can be obtained by applying 0.05 g / m ² or more. Further, if the applied amount is too large, the ink absorbability may be deteriorated. Therefore, the applied amount is preferably 1 g / m ² or less.

  The reason why it is possible to prevent color spots by adding a basic polyaluminum hydroxide compound to the coating liquid is that the incorporation of the compound suppresses the penetration of the coating liquid into the base paper and makes it difficult for spotted spots to occur. For the reason. Such an action is a characteristic action of the compound, and when a general organic polymer is added, the color spot is extremely deteriorated, and such an action cannot be obtained.

  Since the basic polyaluminum hydroxide compound also has a function as an ink fixing agent, other ink fixing agents can be used without blending. Use of a magnesium or calcium metal salt as the ink fixing agent is particularly preferable because a higher color spot preventing effect can be obtained and a better printing quality can be obtained.

Various pigments may be added to the coating liquid according to the present invention. However, since the texture of the non-coated paper is impaired when the amount of the pigment added is increased, it is preferable to add it to the coating solution so that the amount of pigment applied is 2 g / m ² or less, especially when no pigment is added. preferable.

You may add a binder in the coating liquid concerning this invention. However, if the amount of the binder added is increased, the ink absorbability is inhibited and color spots are likely to occur. Therefore, it is preferable to add the binder to the coating liquid so that the amount of the binder applied is 0.5 g / m ² or less. It is particularly preferred that no is added.

  The base paper used for the inkjet recording material of the present invention includes chemical pulps such as LBKP and NBKP, mechanical pulps such as GP, PGW, RMP, TMP, CTMP, CMP, and CGP, and wood pulp such as waste paper pulp such as DIP, and conventionally known pulps. The main component is a pigment, and a binder, a sizing agent, a fixing agent, a yield improver, a cationizing agent, a paper strength enhancer and the like are mixed using one or more additives, and a long net paper machine, circular net paper machine, Paper that has been size-pressed with starch, polyvinyl alcohol, or the like is used for base paper manufactured by various devices such as a twin-wire paper machine, and further for base paper.

When the base paper contains 20% by mass or more of mechanical pulp and / or waste paper pulp, the lightness index L ^* value on the surface of the base paper becomes small, and the amount of colorant used can be reduced.

In the ink jet recording material of the present invention, lightness JIS Z8730 colored surface L ^* is preferably colored so as to become smaller before該明index of the base paper L ^* than 2.5 or more colored. By coloring in this manner, the degree of coloring by the colorant can be adjusted with respect to fluctuations in the surface hue of the base paper, and an ink jet recording material having a stable surface hue can be obtained at all times.

By adjusting the hue of the colored surface to a lightness index L ^* of 80 or more and 85 or less, a color coordinate a ^* of −3.0 or more and 0 or less, and b ^* of 3.0 or more and 9.3 or less, It is preferable to approximate the hue of magazines, magazines, newspapers, etc. When used for color proofing of publications, it is preferable to adjust the hue of the colored surface so that the color difference specified in JIS Z8730 is ΔE2.5 or less with respect to the surface hue of the paper used for actual publication. .

  Application of the coating liquid according to the present invention to the base paper is a conventionally known air knife coater, curtain coater, die coater, blade coater, gate roll coater, bar coater, rod coater, roll coater, bill blade coater, short dwell blade coater, Various apparatuses such as a cast coater, an incline size press, a transfer roll coater, a tab size, a rod coater, and a shim sizer can be used. Moreover, it is also possible to perform double-sided coating, and single-sided sequential or double-sided simultaneous may be used. When performing double-sided coating, the hue of each surface may be different.

Examples Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” and “%” indicate parts by mass and mass% unless otherwise specified. The lightness index L ^* and the color coordinates a ^* and b ^* all indicate values according to JIS Z8730.

<Preparation of base paper 1>
For 100 parts of wood pulp consisting of 80 parts of hardwood kraft pulp and 20 parts of softwood kraft pulp, 25 parts of talc, 0.10 parts of commercially available alkyl ketene dimer, 0.03 parts of commercially available cationic polyacrylamide, 0. A slurry having a solid content concentration of 1% containing 80 parts and 0.40 parts of a sulfuric acid band in water was prepared, and then a paper sheet was made using a long net paper machine at a basis weight of 60 g / m ² , and a lightness index L ^* = 96.0. A base paper 1 having color coordinates a ^* = 0.05 and b ^* = 2.52 was produced.

<Preparation of base paper 2>
100 parts of wood pulp consisting of 80 parts of hardwood kraft pulp and 20 parts of chemiground pulp, 25 parts of talc, 0.10 parts of commercially available alkyl ketene dimer, 0.03 parts of commercially available cationic polyacrylamide, 0. A slurry having a solid content concentration of 1% containing 80 parts and 0.40 part of a sulfuric acid band in water was prepared, and then papermaking was carried out with a basis weight paper machine at a basis weight of 60 g / m ² to obtain a lightness index L ^* = 94.8. A base paper 2 having color coordinates a ^* = 0.35 and b ^* = 4.89 was produced.

<Preparation of base paper 3>
For 100 parts of wood pulp consisting of 80 parts of hardwood kraft pulp and 20 parts of fine paper deinked waste paper pulp, 25 parts of talc, 0.10 parts of commercially available alkyl ketene dimer, 0.03 parts of commercially available cationic polyacrylamide, commercially available cationization After preparing a slurry having a solid content concentration of 1% containing 0.80 parts of starch and 0.40 parts of sulfuric acid band in water, the slurry was made using a long paper machine at a basis weight of 60 g / m ² , and the lightness index L ^* = A base paper 3 having 95.1, color coordinates a ^* = 0.17, and b ^* = 1.62 was produced.

<Preparation of base paper 4>
25 parts of talc, 0.10 parts of commercially available alkyl ketene dimer, 0.03 parts of commercially available cationic polyacrylamide, and commercially available cationized starch for 100 parts of wood pulp consisting of 80 parts of hardwood kraft pulp and 20 parts of deinked waste paper pulp After preparing a slurry having a solid content concentration of 1% containing 0.80 part and 0.40 part of a sulfuric acid band in water, the slurry was made using a long net paper machine at a basis weight of 60 g / m ² , and a lightness index L ^* = 94. A base paper 4 having color coordinates a ^* = − 0.03 and b ^* = 2.63 was produced.

<Preparation of base paper 5>
For 100 parts of wood pulp consisting of 10 parts of hardwood kraft pulp and 90 parts of fine paper deinked waste paper pulp, 25 parts of talc, 0.10 parts of commercially available alkyl ketene dimer, 0.03 parts of commercially available cationic polyacrylamide, and commercially available cationization After preparing a slurry having a solid content concentration of 1% containing 0.80 parts of starch and 0.40 parts of sulfuric acid band in water, the slurry was made using a long paper machine at a basis weight of 60 g / m ² , and the lightness index L ^* = A base paper 5 having 90.6, color coordinates a ^* = − 0.62, and b ^* = 2.05 was produced.

<Preparation of base paper 6>
25 parts of talc, 0.10 parts of commercially available alkyl ketene dimer, 0.03 parts of commercially available cationic polyacrylamide, and commercially available cationized starch for 100 parts of wood pulp consisting of 10 parts of hardwood kraft pulp and 90 parts of newspaper deinked waste paper pulp After preparing a slurry with a solid content concentration of 1% containing 0.80 parts and 0.40 parts of a sulfuric acid band in water, the slurry was made using a long net paper machine at a basis weight of 60 g / m ² , and a lightness index L ^* = 87. A base paper 6 having a color coordinate a ^* = − 0.39 and b ^* = 3.04 was prepared.

<Preparation of coating liquid 1>
91.9 parts of water, 0.18 part of black pigment (TB510 Black TR, manufactured by Dainichi Seika Kogyo Co., Ltd.), basic polyaluminum hydroxide aqueous solution (Purachem WT, concentration: 25%, Riken Green Co., Ltd.) 1.92 parts and 6.0 parts of magnesium chloride hexahydrate were mixed to obtain a coating solution 1.

<Preparation of coating liquid 2>
91.3 parts of water, 0.18 part of black color pigment (TB-510 Black TR, manufactured by Dainichi Seika Kogyo Co., Ltd.), blue color pigment (TB-520 Blue 2B, manufactured by Dainichi Seika Kogyo Co., Ltd.) 0.012 part, yellow coloring pigment (EM YELLOW 2R, manufactured by Toyo Ink Manufacturing Co., Ltd.) 0.06 part, basic polyaluminum hydroxide aqueous solution (Paho # 2S, manufactured by Asada Chemical Co., Ltd.) 2.4 parts Then, 6.0 parts of calcium chloride dihydrate was mixed to obtain a coating liquid 2.

<Preparation of coating liquid 3>
89.6 parts of water, 0.18 part of black color pigment (TB-510 Black TR, manufactured by Dainichi Seika Kogyo Co., Ltd.), blue color pigment (TB-520 Blue 2B, manufactured by Dainichi Seika Kogyo Co., Ltd.) 0.012 part, yellow coloring pigment (EM YELLOW 2R, manufactured by Toyo Ink Manufacturing Co., Ltd.) 0.18 part, basic polyaluminum hydroxide aqueous solution (PAC 250A, manufactured by Taki Chemical Co., Ltd.) 4.0 part, The coating liquid 3 was obtained by mixing 6.0 parts of magnesium chloride hexahydrate.

<Preparation of coating liquid 4>
Instead of adding 1.92 parts of basic polyaluminum hydroxide aqueous solution (Purachem WT, concentration: 25%, manufactured by Riken Green Co., Ltd.) in the preparation of coating liquid 1, The coating liquid 4 was obtained on the same conditions as the coating liquid 1.

<Preparation of coating liquid 5>
Coating solution 2 except that 2.4 parts of water was added instead of adding 2.4 parts of basic polyaluminum hydroxide aqueous solution (Paho # 2S, manufactured by Asada Chemical Co., Ltd.). A coating solution 5 was obtained under the same conditions as in 2.

<Preparation of coating liquid 6>
Coating liquid 3 was prepared except that 4.0 parts of water was added instead of 4.0 parts of basic polyaluminum hydroxide aqueous solution (PAC 250A, manufactured by Taki Chemical Co., Ltd.) in the preparation of coating liquid 3. The coating liquid 6 was obtained on the same conditions.

<Preparation of coating liquid 7>
Coating liquid 7 was obtained under the same conditions as coating liquid 3 except that 6.0 parts of water was added instead of adding 6.0 parts of magnesium chloride hexahydrate in the preparation of coating liquid 3.

Using an air knife coater, “Coating liquid 1” was applied onto base paper 1 so that the wet coating amount was 21 g / m ² and then dried to prepare an ink jet recording material.

Using an air knife coater, “Coating liquid 1” was applied on the base paper 2 so as to have a wet coating amount of 21 g / m ² and then dried to produce an ink jet recording material.

Using an air knife coater, “Coating liquid 1” was applied on the base paper 3 so as to have a wet coating amount of 21 g / m ² and then dried to prepare an ink jet recording material.

Using an air knife coater, “Coating liquid 1” was applied on the base paper 4 so as to have a wet coating amount of 21 g / m ² and then dried to prepare an ink jet recording material.

Using an air knife coater, “Coating liquid 1” was applied on the base paper 4 so as to have a wet coating amount of 3.3 g / m ² and then dried to produce an ink jet recording material.

Using an air knife coater, “Coating liquid 1” was applied on the base paper 5 so as to have a wet coating amount of 9.4 g / m ² and then dried to prepare an ink jet recording material.

Using an air knife coater, “Coating liquid 1” was applied on the base paper 6 so as to have a wet coating amount of 3.3 g / m ² and then dried to produce an ink jet recording material.

Using an air knife coater, “Coating liquid 2” was applied onto base paper 1 so as to have a wet coating amount of 21 g / m ² and then dried to prepare an ink jet recording material.

Using an air knife coater, “Coating liquid 2” was applied on the base paper 6 so as to have a wet coating amount of 9.4 g / m ² and then dried to prepare an ink jet recording material.

Using an air knife coater, “Coating liquid 3” was applied on base paper 1 so as to have a wet coating amount of 21 g / m ² and then dried to prepare an ink jet recording material.

Using an air knife coater, “Coating liquid 3” was applied on the base paper 5 so as to have a wet coating amount of 9.4 g / m ² and then dried to prepare an ink jet recording material.

Using an air knife coater, the “coating liquid 3” was applied onto the base paper 6 so as to have a wet coating amount of 3.3 g / m ² and then dried to produce an ink jet recording material.

Using an air knife coater, “Coating Liquid 7” was applied on base paper 1 so as to have a wet coating amount of 21 g / m ² and then dried to prepare an ink jet recording material.

Comparative Example 1
Using an air knife coater, “Coating liquid 4” was applied on the base paper 1 to a wet coating amount of 21 g / m ² and dried to prepare an ink jet recording material.

Comparative Example 2
Using an air knife coater, “Coating liquid 4” was applied on base paper 2 so as to have a wet coating amount of 21 g / m ² and then dried to prepare an ink jet recording material.

Comparative Example 3
Using an air knife coater, “Coating liquid 4” was applied on the base paper 3 so as to have a wet coating amount of 21 g / m ² and then dried to prepare an ink jet recording material.

Comparative Example 4
Using an air knife coater, “Coating liquid 4” was applied on the base paper 4 so as to have a wet coating amount of 21 g / m ² and then dried to prepare an ink jet recording material.

Comparative Example 5
Using an air knife coater, the “coating liquid 4” was applied on the base paper 4 so as to have a wet coating amount of 3.3 g / m ² and then dried to produce an ink jet recording material.

Comparative Example 6
Using an air knife coater, “Coating liquid 4” was applied on the base paper 5 so as to have a wet coating amount of 9.4 g / m ² and then dried to produce an ink jet recording material.

Comparative Example 7
Using an air knife coater, “Coating liquid 4” was applied on the base paper 6 so as to have a wet coating amount of 3.3 g / m ² and then dried to produce an ink jet recording material.

Comparative Example 8
Using an air knife coater, “Coating liquid 5” was applied on base paper 1 so as to have a wet coating amount of 21 g / m ² and then dried to produce an ink jet recording material.

Comparative Example 9
Using an air knife coater, the “coating liquid 5” was applied on the base paper 6 so as to have a wet coating amount of 9.4 g / m ² and then dried to prepare an ink jet recording material.

Comparative Example 10
Using an air knife coater, the “coating liquid 6” was applied on the base paper 1 to a wet coating amount of 21 g / m ² and then dried to prepare an ink jet recording material.

Comparative Example 11
Using an air knife coater, the “coating liquid 6” was applied on the base paper 5 so as to have a wet coating amount of 9.4 g / m ² and then dried to prepare an ink jet recording material.

Comparative Example 12
Using an air knife coater, the “coating liquid 6” was applied on the base paper 6 so as to have a wet coating amount of 3.3 g / m ² and then dried to produce an ink jet recording material.

Evaluation The ink jet recording materials produced in Examples 1 to 13 and Comparative Examples 1 to 12 were evaluated by the following methods.

[Lightness index L ^* and color coordinates a ^* , b ^* ]
The lightness index L ^* and the color coordinates a ^* and b ^* of the surface coated with the coating solution were measured by the method described in JIS Z8730. The results are shown in the L ^* , a ^* and b ^* columns of Table 1. The value obtained by subtracting the L ^* value of the base paper from the L ^* value of the coated surface is shown in the L ^* difference column of Table 1.

[Observation of the colored state of the coated surface]
The colored spots on the surface to which the coating solution was applied were visually evaluated. The results are shown in Table 2.

[Texture of coated surface]
The texture of the surface to which the coating solution was applied was evaluated by visual and tactile sensation when touched by hand. The ink jet recording materials of Examples 1 to 13 and Comparative Examples 1 to 12 were all good because they had a texture similar to that of uncoated paper such as weekly magazines, magazines, and newspapers.

[Print evaluation]
An image was printed on the surface on which the coating liquid was applied using an ink jet printer “PX-9000 (printer setting: MC art paper, recommended setting, vivid color)” manufactured by Seiko Epson Corporation. The images used for evaluation consisted of solid prints of black, cyan, magenta, yellow, blue, red, green, and patterns with white characters in them, and the print density, ink absorptivity, and ink at each color boundary. The bleeding was evaluated. The results are shown in the columns of printing density, ink absorbency and ink bleeding in Table 3. A mark indicates that the print density is sufficiently high, the ink absorbability is good, and the ink bleeding at each color boundary is not visually observed. Δ indicates that the print density is slightly low and fine ink bleeding is visually observed.

  In Table 1, as shown in Examples 1 to 13, by applying and coloring a coating liquid containing basic polyaluminum hydroxide, a colorant and an ink fixing agent to a base paper, a weekly magazine, a magazine, a newspaper, etc. An ink jet recording paper containing mechanical pulp and / or waste paper pulp and having a low whiteness and a similar texture and surface hue and having no surface hue unevenness and capable of good printing by an ink jet method could be obtained.

  In Examples 2 to 7, 9 and 11 to 12 containing mechanical pulp or waste paper pulp in the base paper, some pulp fibers in the base paper are particularly darkly colored and the surface hue becomes uneven. Compared with Comparative Examples 2 to 7, 9 and 11 to 12 which do not contain basic polyaluminum hydroxide, the appearance of the coated surface was very good.

Example 7 where the lightness index L ^* according to JIS Z8730 of the colored surface is 80 or more and 85 or less, and the color coordinate a ^* is −3.0 or more and 0 or less, and b ^* is 3.0 or more and 9.3 or less. , 8 and 10-13 were good because the surface hue was particularly similar to weekly magazines, magazines, newspapers and the like.

  Examples 1 to 12 containing magnesium or calcium metal salt in the coating liquid have higher printing density, no ink bleeding, and better printing characteristics compared to Example 13 not containing the metal salt. Obtained.

  In Comparative Examples 1 to 12, which do not contain basic polyaluminum hydroxide in the coating liquid, scale-like colored spots are generated, or some pulp fibers are particularly darkly colored and the surface hue becomes uneven, Compared to weekly magazines, magazines, newspapers, etc., it was a very unsightly surface.

Claims (5)

  An ink jet recording material in which a coating liquid containing a colorant and an ink fixing agent is applied and colored on at least one side of a base paper, wherein the coating liquid contains basic polyaluminum hydroxide. Jet recording material according to claim 1, wherein the lightness JIS Z8730 colored surface L ^* is from 2.5 or more smaller該明index of the precolored raw paper L ^*.   3. The ink jet recording material according to claim 1, wherein the ink fixing agent is a metal salt of magnesium or calcium.   The ink jet recording material according to any one of claims 1 to 3, wherein the base paper contains 20 mass% or more of mechanical pulp and / or waste paper pulp. The lightness index L ^* according to JIS Z8730 of the colored surface is 80 or more and 85 or less, and the color coordinate a ^* is −3.0 or more and 0 or less, and b ^* is 3.0 or more and 9.3 or less. The ink jet recording material according to any one of claims 1 to 4.