JP2000079752A - Ink jet recording medium and method for recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a medium to be recorded for recording by using a pigment ink having excellent weather resistance particularly in an ink jet type for simply, easily obtaining a color image. SOLUTION: In the ink jet recording medium for recording by using ink containing a pigment as a color developing component by providing an ink receiving layer containing at least one type of pigment selected from an amorphous silica, alumina and aluminosilicate and a binder on a support, the receiving layer further contains a cationic resin having a cationic intensity measured by a colloidal titration process of 1.5 to 6 m equivalent/g.

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 method used for image recording, printing, and the like, and more particularly to an ink jet recording method in which the bleeding of an ink is small in recording using a pigment ink and the color development of a printed matter is excellent.

[0002]

2. Description of the Related Art The technical progress of an ink jet color printer for producing a color hard copy at a high speed has made it possible to obtain a clear image and excellent print quality. However, on the other hand, in order to further improve the print quality, saturation, appearance, and image, a recording material having higher characteristics has been required. In particular, due to improvements in printing speed, resolution, saturation, etc., more advanced properties such as quick drying of ink, high absorption capacity, control of dot diameter and bleeding are required for recording materials, and various types of recording are required. Sheets have been developed. JP-A-55-5183, JP-A-56-148585 and the like disclose that a receiving layer made of a porous inorganic pigment is provided on a substrate in order to improve ink absorption.

On the other hand, in recent years, ink jet printers have been used for printing wide-ranging advertisements, such as posters, from conventional printing of documents and the like. Inkjet printers are very easy to operate and, unlike printing such as plate making, are capable of printing in small quantities, so they can quickly print the required image in the required amount. In addition, for printing advertisements and the like, what is called a plotter or the like that can be printed in a wide width is usually used. Since these plotters are used for advertisements, images must be clearly visible even from a distance, and it is necessary to maintain clear images even in long-term posting. However, conventionally used ink jet inks are dye inks, which have been oxidized by ultraviolet rays, ozone, and the like in long-term display, causing a problem in that images are discolored and appearance is deteriorated. In order to solve such a problem, Japanese Patent Application Laid-Open No. Hei 9-157559 discloses that a pigment ink having higher light resistance than a dye ink is used as a plotter ink.
It is disclosed in JP-A-9-132740 and the like. However, dye inks "dye" the receiving layer with low molecular weight compounds
However, since the pigment ink develops the color by "laying" or "arranging" the pigment particles on the receiving layer, the characteristics required for the recording medium are different. In addition, pigments have a much larger molecular weight than dyes, so the fixing mechanism, such as bleeding control, is completely different from the low-molecular-level reaction of dyes. At present, sufficient characteristics cannot be obtained.

[0004] Further, also in label applications having a pressure-sensitive adhesive layer and a release paper on the back surface, in particular, storability of the recording portion is required, and therefore, a recording medium corresponding to pigment ink is required. However, in this method using a pigment ink, the recording density is hard to come out as compared with the method using a disperse dye, and conversely, if the ink is left on the recording medium surface in order to obtain the recording density,
There were drawbacks in that the image became thin or the background became dirty due to the rubbing of the recorded image surface. In addition, there is a disadvantage that when water is applied to the surface of the recorded image, the ink oozes out, that is, the so-called water resistance deteriorates. These problems are disadvantages caused by the fact that the pigment ink is not sufficiently fixed on the recording medium, and cannot be solved by a recording medium corresponding to a disperse dye type ink.

[0005] Regarding the water resistance of printing, when a disperse dye type ink is used, for example, Japanese Patent Laid-Open No. 9-188
No. 062, etc., a method of applying a waterproofing agent before and after printing, or as described in JP-A-55-66976, a recording medium using a volatile organic solvent as a solvent for ink. Although a method of spraying to provide water resistance has been proposed, for example, a method of applying a water-resistant agent complicates the mechanism, and if the liquid absorption capacity of the recording medium is not increased, so-called bleeding is performed. Bleeding occurs. On the other hand, according to this method, there is a problem that maintenance of the waterproofing agent is required together with the ink, and the running cost is increased.

As described above, there is an increasing demand for the use of pigment inks in industrial applications such as ink-jet label paper in which the preservability of the recorded portion is an absolute condition. As a characteristic of the pigment ink type, it is required that the ink is fixed on the surface of the recording medium at a point where the ink lands on the surface of the recording medium. As a fixing mechanism, a method is generally employed in which a cationic component is contained in the ink receiving layer and aggregated, noting that the dispersion of the pigment ink is anionic. In the dye ink type, a large amount of cationic component is necessary for fixing the dye.However, in the pigment ink type, when the cationic component is excessive, coagulation on the surface becomes too strong and the distribution of the ink becomes non-uniform. Since a phenomenon called a ring causes a decrease in the recording density, excellent recording could not be obtained with a conventional recording medium for dye ink.

[0007]

SUMMARY OF THE INVENTION The present invention relates to an ink jet recording system such as an ink jet printer or a plotter using a pigment ink, which can print a high-quality image at a high speed, has a high print density, and has no blur. A recording sheet is provided. Further, the present invention is a recording material having excellent recording properties using a pigment type ink having particularly excellent printing weather resistance, and is particularly suitable for applications where printing water resistance or printing abrasion resistance is required, such as industrial use. Provided is a recording medium having a high ink fixing property and an excellent recording density.

[0008]

The present invention includes the following aspects. [1] An ink receiving layer containing at least one pigment selected from amorphous silica, alumina and aluminosilicate and a binder is provided on a support, and an ink containing a pigment as a color-forming component is used. An ink jet recording medium for recording, wherein the ink receiving layer further has a cation strength of 1.5 meq /
An ink jet recording medium containing a cationic resin having an amount of g to 6 meq / g. [2] The ink jet recording medium according to [1], wherein the cationic resin has a cation strength of 1.5 meq / g or more and 5 meq / g or less. [3] The cationic resin is a polydiallyl dimethyl ammonium salt [1] or [2].
The ink-jet recording medium according to the above. [4] The ink jet recording material according to any one of [1] to [3], wherein the molecular weight of the cationic resin is 30,000 or less. [5] The ink jet recording material according to any one of [1] to [4], wherein the pigment is amorphous silica. [6] The ink jet recording medium according to any one of [1] to [5], wherein the pigment has an average particle diameter of 4 μm or more and 15 μm or less. [7] An ink jet recording method for performing recording by applying ink droplets containing a pigment as a coloring component to the ink jet recording medium according to any one of [1] to [6].

[8] The ink jet recording medium according to [2], wherein the cationic resin has a cation strength of 2 meq / g or more and 4 meq / g or less.

[9] The ink jet recording material according to [3], wherein the polydiallyldimethylammonium salt is polydiallyldimethylammonium hydrochloride. [10] The ink-jet recording material according to [4], wherein the molecular weight of the cationic resin is 21,000 or less.

[0010] The ink jet recording method for pigment ink is as follows.
This is a recording method in which ink droplets are ejected to a receptor layer to form an image, similar to dye ink, and the difference in ink absorbency greatly affects print quality. As the amount of coating increased, the ink absorbency improved, but at the same time, the pigment component was taken in and the print density tended to decrease. On the other hand, when the coating amount was reduced to allow the pigment component to be present on the surface, the bleeding worsened, and the ink solvent was not sufficiently absorbed by the receiving layer, so that the pigment particles moved together with the solvent. Was uneven and the white portion of the receiving layer was exposed in the printed portion, resulting in a decrease in print density. Because dye molecules are very small in dye inks, the dye binds to the receiving layer and becomes colored as it moves with the solvent. Therefore, when the absorption capacity of the receiving layer is low, the print density tends to be improved, but such a phenomenon did not occur at all with the pigment ink. That is, the coloring mechanism of the pigment ink was completely different from that of the dye ink. In the recording method using the pigment ink, the printing density can be improved by uniformly “arranging” or “spreading” the pigment particles on the surface layer of the receiving layer. The properties to be achieved are that the pigment component is uniformly present in the surface layer of the receiving layer, and that the solvent of the ink is quickly absorbed into the receiving layer. The present inventors have conducted intensive studies on the absorption and adsorptivity of the pigment ink in the receiving layer. As a result, the coloring and bleeding of the pigment ink are improved by including the specific cationic resin in the receiving layer. This led to the completion of the present invention.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The ink receiving layer of the present invention has a cation strength of 1.5 meq /
g to 6 meq / g, preferably 1.5 meq / g
Not less than 5.5 meq / g, more preferably not less than 1.5 meq / g but not more than 5 meq / g, further preferably not less than 2 meq / g and not more than 4 meq / g, most preferably not less than 2.5 meq / g and not more than 4 m. By containing a cationic resin of equivalent weight / g or less, a recording sheet excellent in color development and ink bleeding can be obtained. Colloid titration is a titration method that utilizes an ion association reaction between colloid particles. That is, a solution in which an ionic polymer having a known molecular structure is dissolved is defined as a prescribed solution, and the ionic strength (equivalent / g: the amount of ions per 1 g of the sample) of an unknown polymer sample having the opposite ionicity to the known sample is determined. This is a method of measuring ("Colloid titration method", written by Chite, November 20, 1966, Nankodo).
In the titration method, the cation strength of the cationic resin can be measured by using an anionic polymer for the prescribed liquid.

The use of a cationic resin having a cation strength of 1.5 meq / g or more and 6 meq / g or less measured by the above-described measuring method may cause the color development and bleeding of the print in the ink jet recording using the pigment ink. It is not clear whether it is good or not, but it is presumed as follows. The pigment in the ink is chemically ionic in order to be uniformly dispersed in the ink solution. In particular, it is usually practiced to provide an anionic group such as a carboxylic acid,
Therefore, it is possible to ionically bond with the cationic substance. When the cationic substance is a polymer, an aggregate of the polymer may be formed with a plurality of pigment particles. In particular, it is presumed that a polymer having a higher cation strength is more likely to undergo aggregation. The cationic resin conventionally used for an ink jet recording medium has a high cation strength. However, when the receiving layer contains a cationic resin having a cation strength of more than 6 meq / g, when the pigment ink lands on the surface of the receiving layer, the pigment particles are bonded and aggregated with the cationic resin on the surface of the receiving layer. It is considered that the particles cannot uniformly cover the receiving layer, white spots are partially generated, and the print density is lowered.

On the other hand, when a cationic resin having a cation strength of less than 1.5 meq / g is used, since the ionic aggregation does not occur, the pigment component of the ink cannot be captured on the surface of the receiving layer. It is considered that bleeding occurs.

The cationic resin used in the ink receiving layer of the present invention includes polyethyleneimine, polyvinylpyridine, polydialkylaminoethyl methacrylate,
Polydialkylaminoethyl acrylate, polydialkylaminoethyl methacrylamide, polydialkylaminoethyl acrylamide, polyepoxyamine, polyamideamine, dicyandiamide-formalin condensate,
Dicyandiamide polyalkyl-polyalkylenepolyamine condensate, diallyldimethylammonium polymer salt such as polydiallyldimethylammonium hydrochloride, polyvinylamine, polyallylamine, polyallylamine salt, polyvinylamine salt, poly (oxyethyl-1-)
Compounds such as methylene) amine salts, polyvinylbenzylamine salts, polyacrylamidopropylmethylamine salts, polydiallylamine salts, acrylamide / diallylamine salt copolymers, monoallylamine / diallylamine salt copolymers, polyaminedicyanic polymers, and the like; Modified products can be exemplified. Furthermore, by using a polydiallyldimethylammonium salt such as polydiallyldimethylammonium hydrochloride in the ink receiving layer of the present invention, an ink jet recording sheet having more excellent coating film strength can be obtained.

Further, in applications where the rubbing resistance of the recording is required, the specific cationic resin has a molecular weight of 30,000.
Those having 0 or less are preferable. By setting the molecular weight of the cationic resin contained in the ink receiving layer to 30,000 or less, it is possible to obtain a recording medium having a higher recording density and excellent scratch resistance. The molecular weight is preferably 25,000 or less, more preferably 21,000 or less, and most preferably 20,000.
00 or less. Although there is no particular lower limit, it may be about 1,000, but is preferably 2,000 or more. Although the cause is not necessarily clear, if the dispersed pigment in the pigment ink that has landed on the surface of the ink receiving layer is too agglomerated, the surface of the recording material that is not colored between the pigments remains and the recording density as a whole decreases. Further, since the color pigment component in the ink is less penetrated by the aggregation due to the aggregation, the color pigment component remaining on the surface is easily rubbed off. As a result, the recording portion is decolored by the rubbing. It is presumed that the molecular weight has an effect on the aggregation state. If the amount of the cationic resin is small, the effect of improving the printing water resistance and the scratch resistance may not be sufficient. On the other hand, if the amount of the cationic resin is too large, the printing density and the scratch resistance may be reduced. , The ink absorption capacity is reduced, and blurring of the recorded image, which is called bleeding, may occur.

The amount of the cationic resin contained in the ink receiving layer of the present invention is about 0.5 to 100 parts by weight, preferably 5 to 80 parts by weight, based on 100 parts by weight of the pigment. More preferably, it is 10 parts by weight or more and 50 parts by weight. If the amount of the cationic resin is less than 0.5 part by weight, bleeding may occur. If the amount exceeds 100 parts by weight, the print density may be improved, but the drying property of the ink may be reduced. .

The pigment used in the ink receiving layer of the present invention is amorphous silica, alumina or aluminosilicate, and amorphous silica is particularly preferred. Amorphous silica is a method of mixing high-purity silica sand with sodium silicate and sulfuric acid to form a silica sol, and forming the silica sol into a three-dimensional aggregate,
It can be obtained by a method of stopping the growth of secondary aggregates under the influence of temperature, ions and surfactants, or by sedimentation of silicon tetrachloride, or the like. By using these synthetic amorphous silica or the like for the ink receiving layer, a recording sheet having more excellent ink absorbability can be obtained. The average particle diameter of the pigment contained in the ink receiving layer of the present invention is about 1 to 20 μm, and the average particle diameter is preferably 4 μm or more and 15 μm or less, more preferably 6 μm or more and 15 μm or less. By using, a recording sheet having a higher print density can be obtained. When the average particle diameter is 4 μm or more, it is considered that the dots of the landed ink become large and the print density becomes higher. If the average particle size of the amorphous silica exceeds 15 μm, the coated surface may be roughened and the appearance may be deteriorated. Other pigments can be added to the ink-receiving layer in order to improve coating suitability within a range that does not impair ink bleeding and print density, which is the object of the present invention. Other pigments that can be used in the ink receiving layer of the present invention include colloidal silica, calcium carbonate, clay,
Calcined clay, diatomaceous earth, talc, aluminum oxide,
Examples thereof include inorganic pigments such as magnesium aluminosilicate, magnesium carbonate, barium sulfate, zinc oxide, aluminum hydroxide, magnesium hydroxide, and zeolites; and organic pigments such as urea-formalin resin fillers and acrylonitrile-based plastic pigments. These pigments can be used in combination of two or more as necessary.

Examples of the binder contained in the ink receiving layer of the present invention include polyvinyl alcohol, polyvinyl alcohol derivatives such as silyl-modified polyvinyl alcohol and cation-modified polyvinyl alcohol, proteins such as gelatin and casein, starch and oxidized starch. Derivatives, water-soluble polymer binders such as cellulose derivatives such as polyvinylpyrrolidone, hydroxyethylcellulose, hydroxypropylcellulose, and carboxymethylcellulose; conjugated diene-based polymers such as styrene-butadiene copolymer and methylmethacrylate-butadiene copolymer. Water-insoluble polymer binders such as coalescing latex, acrylic polymer latex such as polymer or copolymer of acrylic acid ester and methacrylic acid ester, and vinyl polymer latex such as vinyl acetate copolymer It can be used. One or more of these binders can be appropriately selected and used as needed.

The binder contained in the ink receiving layer of the present invention is preferably contained in an amount of 10 parts by weight or more and 100 parts by weight or less based on 100 parts by weight of the pigment. If the content is less than 10 parts by weight, the strength of the coating film may be reduced due to insufficient adhesive strength of the binder. On the other hand, when the addition amount exceeds 100 parts by weight, the capillary may be blocked due to the increase of the binder component in the coating layer, and the drying property of the ink may be reduced. In addition, a pigment dispersant, an antifoaming agent, a viscosity modifier, a crosslinking agent, a fluorescent dye, a colorant, an antioxidant, an ultraviolet absorber and the like are appropriately used as additives according to production conditions and required performance.

As the support of the present invention, acidic paper, neutral paper,
Papers such as coated paper and cast coated paper, resin films (including paper with resin laminated on the surface), synthetic papers (filling thermoplastic resin with fillers such as inorganic pigments, stretching and inorganic foaming Papers), transparent, translucent, white plastic films and films such as non-woven fabrics, cloths and their composites, metal foils, etc., and at least two or more selected from these. In combination, for example, a sheet-like substance processed for adhesion or decorated by printing or pasting may be used. The pulp material contained in the paper used as the support of the present invention includes red pine, black pine, spruce pine, fir pine, conifers such as cedar, beech,
It is appropriately selected and used from groundwood pulp, sulfite pulp, kraft pulp, semi-chemical pulp, chemical ground pulp, refiner ground pulp, and waste paper pulp mainly using hardwood such as birch and larch.

The paper used as the support of the present invention may be made of clay, talc,
Contains inorganic pigments such as calcium carbonate, calcined kaolin, aluminum oxide, aluminum hydroxide, and titanium oxide, and organic pigments such as urea resin-based fine particles, and internally added rosin-based, alkyl ketene dimer, alkenyl succinic acid, etc. as additives. A sizing agent, a sulfuric acid band, a fixing agent such as cationic starch, a polyacrylamide-based polymer, a paper strength enhancer such as starch, etc. are appropriately selected and internally added, and a base paper formed by a known paper machine is suitably used. . If necessary, rosin-based, petroleum resin-based, oxidized starch, acetylated starch, starch such as hydroxyethylated starch and derivatives thereof, polyvinyl alcohol and derivatives thereof, styrene, alkyd, polyamide, acrylic, olefin, maleic acid, The sizing treatment may be performed with a synthetic resin based on a polymer such as vinyl acetate or two or more copolymers, or a surface sizing agent such as a synthetic resin emulsion or wax based. In addition, in order to adjust the thickness, known equipment such as a machine calendar and a super calendar may be used as necessary.

As the resin film used for the support of the present invention, a thermoplastic resin such as polyester resin and olefin resin can be used. As polyester resin,
Examples include polyethylene terephthalate, polybutylene terephthalate, and polycyclohexene terephthalate, and examples of the olefin resin include those made of polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, or those containing these as main components. it can. In addition, these thermoplastic resins are
A kind or two or more kinds can be appropriately selected and used, and polystyrene, an acrylate copolymer or the like can be mixed and used as another thermoplastic resin. A film formed by stretching these thermoplastic resins in the machine direction and / or the transverse direction may be used. Alternatively, a film may be formed by mixing an inorganic fine powder into the thermoplastic resin, and the film may be biaxially stretched to form a paper-like layer. In the present invention, using a multilayer film obtained by laminating a plurality of such films as a support, for example, a two- or three-layer film provided with a paper-like layer on both sides or one side of the substrate layer, Alternatively, a three- to five-layer film having a surface layer formed on at least one surface of a paper-like layer may be used. What made a thermoplastic resin into a paper-like layer is generally known as synthetic paper. Further, the opacity of such a film is not particularly limited in the present invention.

The method for providing the ink receiving layer on the support is not particularly limited, and a conventionally known method may be used.
It can be provided by a coating machine such as a bar coater, an air knife coater, a blade coater, a die coater, a curtain coater, a gravure coater, and a lip coater. The coating amount of the ink-receiving layer obtained in the present invention is determined by the final use, and need not be unnecessarily increased as long as the ink absorption, color development, and coating film strength are satisfied.
４０40 g / m ^2, preferably 8-30 g / m ² . If the ink receiving layer is less than 5 g / m ² , the ink absorption capacity is often insufficient, causing the image to flow out, drying slowly, and the ink adhering to the paper discharge roll of the printer and becoming dirty. However, 40 g / m
^{When an} ink receiving layer exceeding ² is provided, the strength of the ink receiving layer is weakened, and a problem such as clogging of a head nozzle may be caused by the peeled ink receiving layer,
Further, the cost is high.

The ink receiving layer of the present invention may be a single layer or a multilayer. Corona treatment or various anchor coating treatments can be performed on the support for the purpose of increasing the adhesion between the support and the ink receiving layer. The ink receiving layer can be formed by simultaneously forming a single layer or two or more layers, or by transferring a layer applied in another step to form an ink receiving layer on a support. The sheet provided with the ink receiving layer on the support can be used as it is as the recording sheet of the present invention. For example, the sheet can be treated with a super calender, a gloss calender or the like to impart surface smoothness. . In addition, an adhesive layer is provided on the back surface and processed as an adhesive, or a support is attached to each other to be processed as a double-sided recordable recording medium, and a film is laminated on the ink receiving layer surface after printing, and Known techniques such as protection of the recording surface can be applied.

The recording method applied to the recording paper of the present invention is an ink jet recording method using an ink liquid having a pigment as a color-forming component. The recording liquid is a recording liquid in which an organic or inorganic pigment particle component is dispersed in an aqueous solution or an organic solution containing water, isopropyl alcohol, or the like using a dispersant or the like. Examples of the organic pigment include pigments such as azo, phthalocyanine, perlin, isoindolinone, imidazolone, pyranthrone, and thioindigo pigments.Examples of inorganic pigments include carbon black, graphite, and synthetic iron oxide yellow. , Transparent Bengal, Titanium Yellow, Molybdate Orange, Cuprous Oxide, Cobalt Blue, Ultramarine, CI Pigment Yellow (Yellow Ink), CI Pigment Blue (Cyan Ink), CI Pigme
Pigments such as nt Red (magenta ink) can be exemplified. As the dispersant, various surfactants, low molecular weight dispersant,
A resin-based dispersant having a hydrophilic functional group and a hydrophobic functional group is used. Further, an aqueous resin can be added for the purpose of adjusting the viscosity of the ink. The pigment and the dispersant are blended in a solution, crushed into fine dispersed particles using a disperser such as a paint shaker or a sand mill, and the coarse particles are filtered with a filter having a pore size of 1.0 μm or less to obtain a pigment ink. That is usually done. The solid content concentration in the pigment ink is not particularly limited, but is 0.5 to 30% by weight.

[0026]

EXAMPLES The present invention will be described more specifically with reference to the following examples, but it should be understood that the present invention is not limited by these examples. In the following, parts and% all indicate parts by weight and% by weight. Example 1 Wood pulp (LBKP: freeness 500 ml CSF) 10
0 parts, calcined kaolin (trade name: Ansilex, manufactured by Engelhard Minerals) 10 parts, commercial sizing agent 0.05
Using a papermaking material consisting of 1.5 parts by weight, a sulfuric acid band of 1.5 parts, a wet paper strength agent of 0.5 parts, and starch of 0.75 parts, a high quality paper having a basis weight of 80 g / m ² was produced by a fourdrinier paper machine. The Stechig sizing degree of this high quality paper was 6 seconds. All the paper base materials used in Examples and Comparative Examples of the present invention used this high-quality paper. On one side of the high-quality paper produced by the above method, paint-1 was applied in an absolutely dry amount of 8
After applying g / m ² , drying was performed to obtain an ink jet recording sheet.

Paint-1 100 parts of amorphous silica (average particle diameter: 4.3 μm; trade name: Fine Seal X-45, manufactured by Tokuyama), cationic resin (cation strength: 2.9 meq / g, substance name: dicyandiamide / polyethyleneamine) ; Product name Neofix,
20 parts of Nichika Chemical Co., Ltd., and 60 parts of binder (completely saponified polyvinyl alcohol; trade name: PVA117, manufactured by Kuraray).

Example 2 Paint-2 was applied to one side of the high-quality paper used in Example 1 in an absolutely dry amount.
After coating at 5 g / m ² , drying was performed to obtain an inkjet recording sheet. Paint-2: 100 parts of amorphous silica (average particle diameter: 12 μm; trade name: Sylysia 470, manufactured by Fuji Silysia), 50 parts: cationic resin (cation strength: 3.4 m equivalent / g, substance: dicyandiamide / formaldehyde, manufactured by Nikka Chemical) 30 parts of a binder (partially saponified polyvinyl alcohol; trade name: PVA420, manufactured by Kuraray)

Example 3 Paint-3 was applied on one side of the high-quality paper used in Example 1 on one side in an absolutely dry amount of 15 g / m ² and dried to obtain an ink jet recording sheet. The average particle diameter of the two-mixed amorphous silica of Paint-3 was 8.2 μm. Paint-3 amorphous silica (average particle diameter 4.3 μm; trade name: Fine Seal
X-45, manufactured by Tokuyama) 50 parts, amorphous silica (average particle diameter: 12 μm; trade name: Sylysia 470, manufactured by Fuji Silysia)
50 parts, cationic resin (cation strength: 3.5 m equivalent /
g, molecular weight 4,000, substance name diallyldimethylammonium hydrochloride; Unisense CP-91, manufactured by SENKA) 35
Part, silanol-modified polyvinyl alcohol (trade name: R-
1130, Kuraray) 40 parts, vinyl acetate-ethylene latex (Sumikaflex S-473, Sumitomo Chemical) 5 parts.

Example 4 Synthetic paper having a three-layer structure containing polypropylene and an inorganic pigment and having a central base material layer and paper-like layers on both front and back surfaces (trade name: Yupo FPG-110, manufactured by Oji Oil Chemical Synthetic Paper, thickness: 110 μm)
After applying 15 g / m ² of paint-3 on one side in an absolutely dry amount, drying was performed to obtain an ink jet recording sheet.

Example 5 An ink jet recording sheet was prepared in the same manner as in Example 1 except that the amorphous silica fine seal X-45 of Example 1 was changed to Nip Seal ES (trade name: 18 μm, manufactured by Nippon Silica Industry). I got Comparative Example 1 The cationic resin Neofix of Example 1 was used under the trade name PAA.
-An ink jet recording sheet was obtained in the same manner as in Example 1 except that -HCL-10L (cation strength: 9.2 meq / g, molecular weight: 80,000, substance name: polyallylamine hydrochloride, manufactured by Nitto Boshoku) was used.

Comparative Example 2 The cationic resin of Example 2 was used under the trade name Unisense CP-10.
3 (cation strength: 6.2 meq / g, molecular weight: 100,0
00, except that the substance name was diallyldimethylammonium hydrochloride (manufactured by SENKA), to obtain an ink jet recording sheet in the same manner as in Example 1. Comparative Example 3 The same procedure as in Example 1 was carried out except that the cationic resin Unisense CP-91 of Example 3 was changed to CM-318 (trade name: 0.5 m equivalent / g, cation-modified polyvinyl alcohol, manufactured by Kuraray). Thus, an ink jet recording sheet was obtained.

Comparative Example 4 Same as Example 1 except that amorphous silica fine seal X-45 of Example 1 was changed to Tamapearl TP-121 (average particle diameter: 1.6 μm, manufactured by Okutama Kogyo Co., Ltd.) of light calcium carbonate. Thus, an ink jet recording sheet was obtained.

Table 1 shows the evaluation results of the obtained coated sheet samples. The cation strength of the cationic resin is 0.4g
Add 2 drops of toluidine blue indicator to 10 ml of / 1 cation resin solution, titrate with N / 400 solution of polyvinyl potassium sulfate (PVSK), read the titer at which the solution changed from blue to magenta, and use the following formula The cation strength of the cation resin was determined. Cation strength (m equivalent / g) = [1/400 (equivalent / l) * PVSK titer (ml) * PVSK factor] ÷ [0.4 (g / l) * 10 (ml)] The factor of PVSK used this time is 1.108. The suitability for inkjet recording was evaluated by the following method.

(1) Print density (color developability): Ink jet plotter (NOVA JET PROGO ink)
Using ENCAD, 100% of black, 100% of yellow, 100% of magenta and 100% of cyan were subjected to sensory evaluation. Each ink is an ink containing a pigment as a color-forming component, the black ink has carbon black as a color-forming component, and the solvent is composed of 81.8% of water and 18.2% of diethylene glycol. Magenta ink
Quinacridone magenta (CIPigmentRed122) is used as a coloring component, and the solvent is water 84.7% and diethylene glycol 1
Consisting of 5.3%. ◎ ・ ・ ・ Good print density ○ ・ ・ ・ Slightly bad but no practical problem △ ・ ・ ・ Insufficient in practical use × ・ ・ ・ Poor and bad in practical use

(2) Bleeding: The ink jet plotter (NOVA JET PROGO Ink ENCA)
(Manufactured by Company D), and the bleeding of a 200% multicolor printing portion of 100% cyan and 100% magenta was sensory evaluated. ◎ ・ ・ ・ Good without bleeding ○ ・ ・ ・ Slightly bad but no practical problem △ ・ ・ ・ Insufficient for practical use × ・ ・ ・ Poor and bad for practical use

(3) The strength of the coating film was evaluated by sensory evaluation by performing a cellophane tape (Nichiban) peel test. ◎ ・ ・ ・ Film strength good ○ ・ ・ ・ Slightly bad but no practical problem △ ・ ・ ・ Insufficient for practical use × ・ ・ ・ Poor and bad for practical problems

(4) Appearance: The surface of the coating layer was visually observed and evaluated organoleptically. ◎ ・ ・ ・ The appearance of the coating layer surface is very smooth and very good ○ ・ ・ ・ The appearance is smooth and good △ ・ ・ ・ The appearance is rough and insufficient for practical use × ・ ・ ・ The appearance is very rough There is a problem in practical use

[0039]

[Table 1]

As is clear from Table 1, the ink jet recording sheets obtained in the examples have the following properties:
Excellent in both bleeding and coating strength. On the other hand, the ink jet recording sheet obtained by the comparative example did not show good results in terms of print color development, bleeding, and coating film strength. The ink jet recording sheet of the present invention is excellent in color development of printing, bleeding and coating strength as ink jet recording paper for pigment ink.

Example II-1 A base paper (product name: Marshmallow; manufactured by Oji Paper Co., Ltd., basis weight 105 g / m ² ) having high whiteness and excellent surface smoothness was used as a support. The coating liquid for the ink receiving layer having the following composition was applied so as to have a dry weight of 15 g / m ² and dried to obtain a recording medium. (Coating liquid for ink receiving layer: aqueous dispersion of 20% concentration) 30% aqueous solution of polydiallyldimethylammonium hydrochloride as a cationic resin (trade name: Unisense CP101, manufactured by Senka, cation equivalent: 5.0 meq / g, average molecular weight) 2
(000) 65 parts, amorphous silica (trade name: Fine Seal X-45, manufactured by Tokuyama, 4.3 μm) 100
Parts, polyvinyl alcohol (trade name: PVA105, manufactured by Kuraray) 200% aqueous solution with 10% solid content, water

Example II-2 Example II-1 except that the following coating liquid for an ink receiving layer was used.
A recording medium was obtained in the same manner as described above. (Coating liquid for receiving layer: 20% concentration aqueous dispersion) Polydiallyldimethylammonium hydrochloride 30 as a cationic resin
% Aqueous solution (trade name: Unisense CP90, manufactured by SENKA,
Average molecular weight 4,000, cation equivalent 3.5 m equivalent /
g) 65 parts, amorphous silica (trade name: Fine Seal X-45, manufactured by Tokuyama) 100 parts, polyvinyl alcohol (trade name: PVA105, manufactured by Kuraray), solid content concentration 1
200% 0% aqueous solution, water

Comparative Example II-1 The following coating solution for a receiving layer was coated on the support used in Example II-1 to a dry weight of 15 g / m ^2, and dried to obtain a recording medium. Obtained. (Coating liquid for receiving layer: 20% aqueous solution) 30% aqueous solution of polydiallyldimethylammonium hydrochloride as a cationic resin (trade name: Unisense CP103, manufactured by Senka, average molecular weight 100,000, cation equivalent 6.2 meq /
g) 65 parts, amorphous silica (trade name: Fine Seal X-45, manufactured by Tokuyama) 100 parts, polyvinyl alcohol (trade name: PVA105, manufactured by Kuraray), solid content concentration 1
200% 0% aqueous solution, water

The recording medium obtained above was subjected to GO ink (pigment type ink,
The following colors were printed using a plotter).
100% of single color ink (cyan, yellow, magenta)
And dual colors (red, 200%). Evaluation item (Recording density) The optical density of the solid recording section was measured using a Macbeth densitometer (
It was measured by Macbeth RD-914). The filter was selected according to the color of the ink. (Ink Absorbability) Immediately after recording in the solid recording portion, the recording portion was touched with a finger to check the ink absorbency. : Absorption was sufficient without stickiness. Δ: Slightly sticky, but recording surface is not disturbed. ×: Sticky, at a level that poses a practical problem. (Scratch resistance of recording part) After drying the recording sample for one day,
The recorded portion was rubbed with a finger, and the density of the recorded portion was reduced and the degree of ink adhesion to the finger was visually determined. : The density does not decrease at all, and no ink adheres to the finger. Δ: The ink is not adhered to the finger although a little remains after being rubbed. ×: Marks of rubbing are clearly left, which is a level that poses a problem in practical use.

(Printing Part Bleeding) Bleeding of the ink at the boundary between the multicolor printing and the single-color printing was visually determined immediately after printing. ：: Almost no bleeding was observed. ―: Slight bleeding is observed. Δ: Slight bleeding is observed. X: The bleeding is remarkable and is not practical. Table 2 summarizes the evaluation results. The present invention is a pigment ink type ink jet recording medium which is excellent in recording density, image quality, image preservability, and excellent in rubbing resistance of a recording portion and which provides a clear image without bleeding.

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[Table 2]

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The ink jet recording sheet of the present invention is excellent as ink jet recording paper for pigment inks in color development of printing, bleeding and coating strength.

Claims (7)

[Claims] 1. An ink receiving layer comprising a support and at least one pigment selected from amorphous silica, alumina and aluminosilicate and a binder, and an ink containing a pigment as a color-forming component is provided. An ink jet recording medium for recording using the ink receiving layer, wherein the ink receiving layer further has a cation strength of 1.5 m as measured by a colloid titration method.
An ink jet recording medium containing a cationic resin having an equivalent weight / g of 6 m equivalent / g or less. 2. The cationic resin has a cation strength of 1.
2. The ink jet recording medium according to claim 1, wherein the amount is from 5 meq / g to 5 meq / g. 3. The ink jet recording medium according to claim 1, wherein said cationic resin is a polydiallyldimethylammonium salt. 4. The cationic resin has a molecular weight of 30,00.
The inkjet recording material according to claim 1, wherein the value is 0 or less. 5. The pigment according to claim 1, wherein said pigment is amorphous silica.
5. The ink jet recording material according to any one of items 4. 6. The pigment has an average particle diameter of 4 μm to 15 μm.
The inkjet recording medium according to claim 1, wherein m is equal to or less than m. 7. An ink jet recording method for performing recording by applying ink droplets containing a pigment as a coloring component to the ink jet recording medium according to claim 1.