JP2006001219A - Support for inkjet recording medium, and inkjet recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper support for use in an inkjet recording medium with good surface properties which hardly causes cockling after printing, and the inkjet recording medium using the support. <P>SOLUTION: This support for the inkjet recording medium, at least one side of which possess an ink absorbing layer for performing recording by using inkjet recording ink, is paper which is mainly composed of pulp with no laminate layer made of a thermoplastic resin. In the support, an underwater elongation percentage in a CD direction, which is measured according to J.TAPPI No. 27-B, is 2.0% or less; a Stoeckigt sizing degree in terms of a basis weight of 100 g/m<SP>2</SP>is in the range of 20-150 seconds; and Gurley stiffness in the CD direction, which is measured according to J.TAPPI paper pulp testing method No. 40 in the environment at 30°C and 80% RH, is 2.5 mN or more. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a paper support used for an ink jet recording medium having good surface properties with little cockling after printing, and an ink jet recording medium using the support.

  In recent years, the development of ink jet printer technology has been remarkable, and as the accuracy of the printer has improved, recording quality comparable to the image quality of silver halide photography has been demanded. In response to this, the color reproduction range is expanded, so that the amount of ink driven into the ink jet recording body tends to increase.

  When recording with water-based ink on an ink jet recording material using paper as a support, the ink jet recording material may be blurred or wavy. This phenomenon is called cockling. When cockling occurs, the appearance of the ink jet recording body is impaired, and the quality of the printed matter is lowered. In addition, the distance and angle of the recording head with respect to the ink jet recording body partially change, and the interval between the ink droplets that have been ejected changes to become irregular or misaligned, thereby obtaining the original recording accuracy. As a result, the quality of the recorded matter may be deteriorated. In a more severe case, the ink head may collide with the ink jet recording body, and the recorded image may be stained, the recording paper may be torn, or the recording head may be damaged. Further, when the recorded matter is dried not only immediately after printing as described above but also for several hours or several days, the blur of the ink jet recording material is reduced, but it is not completely eliminated, and the appearance of the ink jet recording material is impaired. become.

  Cockling is thought to occur due to the following causes. That is, the water in the ink driven on the ink jet recording medium penetrates to the support and is absorbed by the pulp fibers of the paper as the support to swell the pulp fibers. It is well known that the swelling rate of pulp fibers by water has a large difference between the axial direction of the fibers and the direction perpendicular thereto, and the fibers are oriented in the flow direction of the paper machine. Therefore, the swelling rate of the paper is larger in the width direction than the flow direction of the paper machine, and anisotropy occurs in the swelling. Further, the amount of ink to be applied to the recording paper is usually small in the dark portion and increased in the dark portion with the density gradation of the pattern. Since cockling is thought to occur due to the anisotropy of the swelling rate of the support and uneven swelling, it is very difficult to improve cockling for recording paper that uses paper as the support. It is.

As a method for improving cockling, Japanese Patent Application Laid-Open No. 62-95285 (see Patent Document 1) discloses an inkjet recording paper made of cast-coated paper provided with a coating layer containing amorphous silica in the lateral direction. An ink jet recording paper having a water immersion elongation of 2.0% or less is disclosed.
Japanese Patent Laid-Open No. 3-199081 (see Patent Document 2) describes the direction in which the base paper is made using the degree of orientation of the pulp fibers of the paper support as a guideline for minimizing the difference between the vertical and horizontal directions. The improvement of cockling is proposed by setting the ratio of the water immersion elongation in the direction (Machine Direction: MD direction) and the water immersion elongation in the direction perpendicular to it (Cross Direction: CD direction) to 1.3 or less.
Furthermore, in Japanese Patent Application Laid-Open No. 2003-276309 (see Patent Document 3), a paper support is disclosed in J. Pat. TAPPI No. 27 When the paper machine and paperboard are made with a paper machine in the Fengchen Stretch Tester described in Method B, the water immersion elongation after 1 minute in the direction perpendicular to the paper traveling direction is 1.5% or less. An ink jet recording medium for a sublimation ink with a certain cockling is described.
Japanese Patent Laid-Open No. 2003-54117 (see Patent Document 4) discloses a recording medium in which contact between the ink head and the recording paper does not occur even during full-surface printing. 1) The underwater elongation in the CD direction of the recording paper is 1 .5～0%, 2) a conveying direction Clark stiffness of the recording paper ^{20~80 (cm 3/100),} 3) the ratio of the direction Clark stiffness perpendicular to the Clark stiffness and the conveying direction of the conveying direction 1 The ink-jet recording paper is characterized by being 4 or more.

JP-A-62-95285 (pages 2 and 3) JP-A-3-199081 (first and second pages) JP 2003-276309 A (second and third pages) JP 2003-54117 A (2nd, 3rd and 4th pages)

  However, even in these proposals, the improvement in cockling has not been achieved due to the increase in the amount of ink and the non-uniformity in the amount of ink due to the shading of the image in order to obtain a high-definition recorded image comparable to recent photographic images. It was enough.

In order to obtain an ink jet recording material that can record a high-definition image with good reproducibility, with little post-printing blurring and no cockling in full-color printing, the present inventors have provided a support (paper) for the ink jet recording material. Conducted research.
At the time of recording, the ink is printed on the ink jet recording body and then penetrates into the support substantially simultaneously with drying. That is, the inkjet recording medium support body maintains a state of containing water for a long time. For example, although the technique of patent document 2 and patent document 3 was examined, since it did not consider the behavior after being immersed in a lot of water for a long time, it turned out that it is not necessarily enough for the improvement of cockling. The present inventors obtain an excellent support for an ink jet recording body that does not cause cockling by satisfying a specific condition in consideration of the behavior after being immersed in a large amount of water for a long time. As a result, the present invention has been completed. The present invention provides a support for an ink jet recording material having excellent dimensional stability, less blurring (cockling) after printing, and a good surface property, and an ink jet recording material using the same.

The present invention includes the following embodiments.
(1) In a support for an ink jet recording body having an ink receiving layer for recording with an ink for ink jet recording on at least one side,
The support is a paper whose main component is pulp that does not have a laminate layer of thermoplastic resin; TAPPI No. The elongation in water in the CD direction measured by 27-B is 2.0% or less, the Steecht sizing degree when converted to a basis weight of 100 g / m ² is 20 seconds or more and 150 seconds or less, and 30 ° C. In an environment of 80% RH, TAPPI Paper Pulp Test Method No. 40. A support for an inkjet recording medium, wherein the Gurley stiffness in the CD direction measured according to 40 is 2.5 mN or more.

The elongation in water in the CD direction is preferably 2.0% or less, and more preferably 1.8% or less. The Steecht sizing degree is preferably 20 seconds or longer and 150 seconds or shorter, and more preferably 25 seconds or longer and 100 seconds or shorter. The Gurley stiffness in an environment of 30 ° C. and 80% RH is preferably 12 mN or less, and more preferably 3.0 mN or more and 10 mN or less.
The support is preferably coated or impregnated with a wet paper strength enhancer.

(2) The support for an ink jet recording material according to (1), wherein the pulp includes dry pulp and / or recycled pulp that has undergone a drying history.
(3) The support for an ink jet recording material according to (2), comprising dry pulp and / or recycled pulp that has undergone a drying history of 5% or more, preferably 15% or more of the total pulp.

(4) An ink jet recording material comprising at least one ink receiving layer having a pigment, an adhesive, and an ink fixing agent on one surface of the support for an ink jet recording material according to any one of (1) to (3). .
(5) At least one ink receiving layer having a pigment, an adhesive, and an ink fixing agent is provided on one side of the support for an inkjet recording medium according to any one of (1) to (3), An ink jet recording material having a glossy layer containing a pigment having an average particle size of 0.5 μm or less on the layer.
(6) Inkjet recording having an ink receiving layer on one side of the support for an inkjet recording body according to any one of (1) to (3), and the surface of the ink receiving layer being finished by a mirror drum Is the body.
(7) A temperature-sensitive polymer compound that reversibly exhibits hydrophilicity and hydrophobicity depending on temperature is provided on one side of the support for an inkjet recording material according to any one of (1) to (3). An ink jet recording body having an ink receiving layer.

  The support for an ink jet recording body of the present invention provides an ink jet recording body having an ink receiving layer on its surface. When a photographic image is recorded on the ink jet recording body, a good surface property with less cockling is obtained. The printed matter is obtained.

[Support for inkjet recording medium]
The present invention requires that the following four conditions of “1” to “4” be satisfied in the support for an ink jet recording body having an ink receiving layer for recording with the ink for ink jet recording on at least one side.
“1” The support is a paper whose main component is pulp that does not have a laminate layer of thermoplastic resin.
“2” TAPPI No. The elongation in water in the CD direction measured by 27-B is 2.0% or less.
“3” The degree of squeecht size when converted to a basis weight of 100 g / m ² is from 20 seconds to 150 seconds.
“4” JAPAN TAPPI Paper Pulp Test Method No. 30 in an environment of 30 ° C. and 80% RH. Gurley stiffness in the CD direction measured according to 40 is 2.5 mN or more.

“1” is a paper whose main component is a pulp that does not have a laminate layer of thermoplastic resin.
There have been proposed various ink jet recording materials that are close to photographic image quality and have no cockling, using polyolefin resin-coated paper as a support. Since the resin coating layers are provided on both sides of the paper, the ink at the time of recording does not permeate the paper as the support, so that cockling does not occur. However, an ink jet recording body using resin-coated paper has to absorb ink only by the ink receiving layer, so that blurring occurs, a high coating amount of the ink receiving layer is necessary, and it is expensive. Or The present invention prevents cockling without employing resin-coated paper, using paper mainly composed of pulp as a support, and without forming a resin-coated layer.

“2” The paper of the support is TAPPI No. The elongation in water in the CD direction measured by 27-B is 2.0% or less. The elongation in water in the CD direction is preferably 1.8% or less, and more preferably 1.6% or less. Incidentally, when the underwater elongation exceeds 2.0%, cockling tends to occur.

The paper of the “3” support has a Steecht sizing degree of 20 to 150 seconds when converted to a basis weight of 100 g / m ² .
When the basis weight of the support is converted to 100 g / m ² , the steak human sizing degree (value obtained by dividing the measured base sizing degree degree by the basis weight and multiplying by 100) is 20 seconds or longer and 150 seconds or shorter. . Preferably, it is 25 seconds or more and 100 seconds or less. When the sizing degree exceeds 150 seconds, the absorption speed of the ink receiving layer is slowed, and the ink absorption to the support can be suppressed, and there is little cockling, but the absorption limit of the ink receiving layer is exceeded. There is a high possibility that the recorded image blurs or the printed ink does not dry on the surface of the recording paper and remains for a long time, and the apparatus or the continuously printed recording paper is soiled. On the other hand, when the time is less than 20 seconds, the ink permeates more quickly, and the ink permeates more into the support, thus facilitating cockling.

“4” The paper of the support was tested under the conditions of JAPAN TAPPI Paper Pulp Test Method No. 30 in an environment of 30 ° C. and 80% RH. The Gurley stiffness in the CD direction measured according to 40 is 2.5 mN or more.
When the support for an ink jet recording body is reduced in stiffness due to moisture absorption or water absorption, the swelling as a result of penetration of the ink solvent cannot be suppressed, and the paper as the support is deformed to cause cockling. Therefore, cockling can be suppressed if the decrease in stiffness can be suppressed by moisture absorption or water absorption. Therefore, according to the present invention, the Gurley stiffness of the support in the CD direction can be measured according to J. C. et al. TAPPI Paper Pulp Test Method No. Measure according to 40. This Gurley stiffness needs to be 2.5 mN or more. If the stiffness is lower than 2.5 mN, the ink jet recording medium cannot withstand swelling due to ink absorption during recording, and cockling may occur. If the Gurley stiffness exceeds 12 mN, there is a possibility that a problem occurs in the paper conveyance of the printer. Therefore, the Gurley stiffness is preferably 12 mN or less. More preferably, it is 3.0mN-10mN.

  The present invention is an ink jet recording support characterized by satisfying all of the above conditions "1" to "4". By satisfying all of these conditions, especially by satisfying that the Gurley stiffness is 2.5 mN or more even when exposed to the high humidity of “4” as well as “1” to “3”, a large amount of It becomes a support for an ink jet recording material in consideration of the behavior after being immersed in water for a long time.

Furthermore, the support for inkjet recording bodies will be specifically described.
The pulp used for the support for the inkjet recording material of the present invention includes chemical pulp such as softwood bleached kraft pulp (hereinafter NBKP), hardwood bleached kraft pulp (hereinafter LBKP), sulfite pulp (SP), soda pulp (AP) and the like. Semi-chemical pulp such as semi-chemical pulp (SCP), Chemi-Grandwood pulp (CGP), mechanical pulp such as groundwood pulp (GP), thermomechanical pulp (TMP, BCTMP), refiner Grandwood pulp (RGP), straw, Non-wood pulp, etc., made from mitsuwa, hemp, kenaf, etc. can be used. Moreover, when high whiteness is required, pulp bleached by combining various bleaching methods such as chlorine, chlorine dioxide, oxygen, ozone, hydrogen peroxide, and hypochlorous acid can be used as appropriate. Among them, so-called ECF bleaching and TCF bleached pulp that does not use chlorine are preferably used because they do not easily cause yellowing. Furthermore, recycled pulps obtained by drying these pulps once or twice or recycled pulps such as process recovered pulp (DIP) can be exemplified and used.

  As the pulp, it is preferable to add 5% or more, preferably 10% or more, of pulp having undergone drying history or recycled pulp in the total pulp. By using such a pulp, the conditions of the present invention are easily satisfied and cockling is greatly improved. When the addition rate is less than 5%, a sufficient cockling improvement effect may not be obtained.

  In the present invention, a pulp having undergone a drying history is a pulp production method generally performed, for example, after undergoing steps such as chip cooking, bleaching and washing, and then drying until the moisture content of the fiber is 4.0% or less. Pour pulp. Such a pulp has a small distortion of the fiber itself, a small deformation from swelling to drying, and tends to be excellent in dimensional stability. For this reason, the support for inkjet recording bodies using the pulp which passed through the drying history also has low elongation in water, and cockling is suppressed as an inkjet recording body.

  Recycled pulp also tends to have excellent dimensional stability due to small distortion of the fiber itself and small deformation from swelling to drying. For this reason, the support for inkjet recording bodies using the pulp which passed through the drying history also has low elongation in water, and cockling is suppressed as the recording body. Pulp that has undergone a drying history and recycled pulp can be used in combination.

  The above-mentioned pulp (preferably pulp having undergone drying history or recycled pulp) can be beaten using commonly used beating means such as a cylindrical refiner, a conical refiner, or a disk refiner. The beating degree in this case is a Canadian standard freeness of about 100 ml to 600 ml, more preferably 200 to 500 ml. Incidentally, when it exceeds 600 ml, the fibrillation of the pulp fibers is not sufficient, the interfiber bonding is inhibited, and sufficient paper strength cannot be obtained. If it is lower than 100 ml, fibrillation is sufficient, but the strength of the fiber itself may be impaired, and the required paper strength may not be obtained.

  Supports include inorganic pigments such as talc, kaolin, calcium carbonate, white carbon, amorphous silica, diatomaceous earth, titanium oxide, activated clay, barium sulfate, urea formalin resin, nylon powder, polyethylene powder, etc. These organic pigments can be added as a filler and adjusted by an ordinary method using acidic or neutral papermaking.

  Further, sizing agents represented by rosin-based sizing agents, alkenyl succinic anhydrides, alkyl ketene dimers, etc., starches such as oxidized starch, enzyme-modified starch, cation-modified starch, esterified starch and etherified starch, methylcellulose, ethylcellulose , Carboxymethylcellulose, methoxycellulose, hydroxycellulose, fully saponified or partially saponified polyvinyl alcohol, carboxy-modified polyvinyl alcohol, silicon-modified polyvinyl alcohol, cation-modified polyvinyl alcohol and other polyvinyl alcohols, polyacrylamide, polyvinyl pyrrolidone, acrylic acid amide and acrylic acid Ester copolymer, acrylic acid amide / acrylic acid ester / methacrylic acid copolymer, alkali salt of styrene / maleic anhydride copolymer, isobutylene・ Maleic anhydride copolymer Water-soluble polymer such as alkali salt, casein, polyvinyl acetate, polyurethane, polyacrylic acid, polyacrylic ester, polybutyl methacrylate, styrene-butadiene copolymer, vinyl chloride / vinyl acetate An adhesive typified by latex such as a polymer, a wet paper strength enhancer such as a polyamide / epichlorohydrin resin, an N-vinylformamide / vinylamine copolymer, can be used by internal addition, coating or impregnation.

  Among these, a wet paper strength enhancer, particularly a polyamide / epichlorohydrin resin, is particularly suitable because it has the effect of effectively improving the dimensional stability of paper when wet. In addition, the Steecht sizing degree can be adjusted by selecting a sizing agent.

Various paper machines such as a long paper machine, a cylindrical paper machine, a Yankee paper machine, a twin wire former, and an inclined wire former are used as a means for paper making. Can be used. Although the basis weight is not particularly defined, 20~400g / ^{m 2,} preferably ^{50g / m 2 ~250g / m 2} , having good surface smoothness can be used normally.

[Inkjet recording medium]
The support for an ink jet recording body of the present invention can be imparted with recording suitability by an ink for ink jet recording, for example, by applying and impregnating a cationic compound or the like on at least one side, but on at least one side of the support, It is preferable to form an ink receiving layer mainly composed of a pigment and an adhesive, which performs recording with an inkjet recording ink. An undercoat layer can also be formed between the support and the ink receiving layer.

(Undercoat layer)
The purpose of the undercoat layer is to cover the unevenness of the support (paper), increase the surface smoothness of the inkjet recording body, increase the concealability of the inkjet recording body, improve the whiteness of the inkjet recording body, and act as a barrier layer to support For example, ozone and NOx such as ozone and NOx that enter the ink receiving layer from the body (paper) side are reduced in gas that deteriorates the pigment.

  Pigments used for the undercoat layer are titanium oxide, zinc oxide, light calcium carbonate, heavy calcium carbonate, magnesium carbonate, barium sulfate, clay, kaolin, calcined kaolin, satin white and other inorganic pigments, (meth) acrylic acid esters Examples thereof include organic resin particles made of various synthetic resins such as resin, styrene- (meth) acrylic acid ester copolymer resin, styrene resin, urea-formalin resin, benzoguanamine resin, and nylon resin. Among these pigments, titanium oxide, light calcium carbonate, and styrene- (meth) acrylic acid ester copolymer resin particles are preferable. From the viewpoint of whiteness, hiding property, and smoothness, titanium oxide and styrene- (meth) are particularly preferable. Acrylic ester copolymer hollow resin particles are preferably used. Moreover, you may use together as needed.

  The shape and particle size of these pigments can be appropriately selected depending on the required quality of the undercoat layer. Incidentally, when using titanium oxide and hollow resin particles, the particle diameter is preferably 0.1 to 5.0 μm, and more preferably 0.3 to 3 μm. If the particle size is small, the strength and color developability tend to be reduced. If the particle size is large, a smooth and uniform surface cannot be obtained.

  The adhesive used for the undercoat layer can be appropriately selected from aqueous emulsions, water-soluble polymers, and solvent-based polymers that are usually used for paper processing. Examples of aqueous emulsions include styrene-butadiene latex, methyl methacrylate-butadiene latex, acrylonitrile-butadiene latex, (meth) acrylic ester emulsion, vinyl acetate emulsion, ethylene-vinyl acetate emulsion, urethane emulsion. Etc. Examples of the water-soluble polymer include polyvinyl alcohol and derivatives thereof, starch and modified products thereof, cellulose derivatives such as carboxymethyl cellulose, casein, and gelatin. Examples of the solvent polymer include a resin in which an organic solvent such as toluene, ethyl acetate, methyl ethyl ketone or the like is dissolved or dispersed. Among these adhesives, water-based emulsions and water-soluble polymers are preferable from the viewpoint of ease of handling, safety and hygiene, and water-based emulsions are particularly advantageous in the drying process because they can be water-resistant and highly concentrated. It is done. Moreover, when using aqueous | water-based emulsion resin, the thing whose glass transition temperature of this polymer is -30-40 degreeC is preferable. If it is lower, the film strength is not sufficient, and if it is higher, film formation in the drying process is insufficient and the film strength may be lowered.

The ratio of the pigment to the adhesive is about 2 to 30 parts, preferably about 5 to 20 parts, with respect to 100 parts of the pigment. When the amount of the adhesive is small, the strength of the undercoat layer is lowered, and when the amount of the adhesive is too large, the absorption amount is lowered and the color development is deteriorated, and the whiteness tends to be lowered.
Furthermore, for the undercoat layer, a crosslinking agent that improves water resistance and film strength, an ultraviolet absorber, an antioxidant, an antioxidant, a pH adjuster, a chelating agent, various dyes and pigments for coloring, and a fluorescent brightening agent , Preservatives, thickeners for imparting coating suitability, surfactants, antifoaming agents and the like can be appropriately blended.

The coating material thus prepared can be appropriately set according to the purpose in the range of 1 to 30 g / m ² as a dry coating amount, and preferably 5 to 15 g / m ² . If the amount is less than 1 g / m ² , the effect is not sufficient, and if it is more than 30 g / m ² , the interlayer strength tends to be weak, or the drying process is economically disadvantageous.

  As the coating apparatus for forming the undercoat layer, various known coating apparatuses such as a blade coater, an air knife coater, a roll coater, a bar coater, a gravure coater, a rod blade coater, a lip coater, a curtain coater, and a die coater. Can be mentioned. Moreover, it can also coat with the coating apparatus attached to a paper machine. After coating, it may be finished using a calendar such as a machine calendar, a TG calendar, a super calendar, or a soft calendar.

(Ink receiving layer)
An ink receiving layer for recording with an ink for ink jet recording is formed on the support for an ink jet recording body of the present invention or on an undercoat layer formed on the support to form an ink jet recording body. Inkjet recording materials are mat type with low gloss using a pigment with a relatively large particle size for the ink receiving layer, gloss type using pigment with a small particle size for the recording layer, and gloss type. However, there are various forms such as a cast type in which the outermost layer of the recording layer is pressed against a mirror drum and finished.

  The present invention is not particularly limited in form as long as it uses a paper support. However, glossy ink jet recording materials are often required to have high-quality images, particularly image quality close to that of photographs, and when such images are recorded, the amount of ink increases, so cockling The problem is remarkable. Further, many glossy type ink jet recording materials have improved surface smoothness in order to impart glossiness. When cockling occurs, cockling tends to be noticeable. The support for an ink jet recording material of the present invention is preferable because it is excellent in action effect in a glossy ink jet recording material having a large cockling problem.

  Next, the ink receiving layer will be described. The ink receiving layer contains a pigment and a binder, and is used by blending a cationic dye fixing agent and other auxiliary agents as necessary.

  As pigments used in the ink receiving layer, amorphous silica, calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, Examples include inorganic pigments such as white carbon, alumina, zeolite, and aluminum hydroxide, and organic pigments such as styrene, acrylic, urea resin, melamine resin, and benzoguanamine resin. The above can be used together. Among these, it is preferable to contain amorphous silica, alumina, and zeolite as main components.

  In addition, as a binder for the ink receiving layer, starch and derivatives thereof, carboxymethyl cellulose, hydroxyethyl cellulose, casein, gelatin, natural or semi-synthetic polymers such as soybean protein, polyvinyl alcohol and derivatives thereof, polyvinyl butyral resin, polyethyleneimine series Resin, polyvinylpyrrolidone resin, poly (meth) acrylic acid resin, acrylate resin, polyamide resin, polyacrylamide resin, polyester resin, urea resin, melamine resin, styrene-butadiene copolymer, methyl methacrylate Known solutions such as aqueous solutions or dispersions of vinyl copolymer resins such as butadiene copolymers and ethylene / vinyl acetate copolymers, or modified polymers in which anionic or cationic residues are introduced into the above resins Material of It can be used as appropriate.

Furthermore, for the purpose of improving the water resistance of a printed image with water-based ink, it is preferable that the ink receiving layer contains a cationic dye fixing agent. Examples of the cationic dye fixing agent include 1) polyalkylene polyamines such as polyethylene amine and polypropylene polyamine, or derivatives thereof, 2) acrylic having a secondary amine group, a tertiary amine group, and a quaternary ammonium group. Resin, 3) polyvinylamine, polyvinylamidine, 5-membered ring amidines, 4) dicyandication resin typified by dicyandiamide-formalin polycondensate, 5) polyamine cation resin typified by dicyandiamide-diethylenetriamine polycondensate, 6) epo chlorohydrin - dimethylamine addition polymers, 7) dimethyldiallylammonium chloride -SO ₂ copolymer, 8) diallylamine -SO ₂ copolymer, 9) dimethyldiallylammonium chloride polymer, 10) of allylamine salt Polymer 11) dialkylaminoethyl (meth) acrylate quaternary salt polymer, 12) acrylamide-diallylamine salt copolymer, 13) aluminum salt such as polyaluminum chloride, polyaluminum acetate, polyaluminum lactate, etc. Can be mentioned. In addition, as addition amount of a cationic dye fixing agent, 1-30 mass parts is preferable with respect to 100 mass parts of pigments, and 2-15 mass parts is more preferable. Two or more ink receiving layers can be formed. In this case, it is preferable to contain a cationic dye fixing agent in at least the upper layer.

  For the ink receiving layer, pigment dispersing agents, thickeners, antifoaming agents, antifoaming agents, foaming agents, mold release agents, penetrating agents, wetting agents, thermal gelling agents, lubricants, etc. Various auxiliary agents known in the art can also be used.

The coating amount of the ink receiving layer is not particularly limited and can be determined according to the required recording quality, but cockling is a problem especially when a high-quality recorded material is required. The total coating amount is 5 g / m ² or more and 45 g / m ² or less, preferably 12 g / m ² or more and 40 g / m ² or less. If the coating amount is small, it is difficult to obtain a recorded material with high precision image reproducibility. Conversely, if the coating amount is large, the recording density and surface strength may be lowered. The coating layer preferably has two or more layers rather than one layer.

  As a means for coating the ink receiving layer, it is appropriately selected from commonly used coating means such as a size press, a gate roll, a roll coater, a bar coater, an air knife coater, a rod blade coater, a blade coater, a die coater, and a curtain coater. You can choose. Moreover, it can smooth | blunt using calendar | calender apparatus, such as a machine calendar, a super calendar, and a soft calendar, after application | coating.

  Among the pigments constituting the ink receiving layer, when a pigment having an average particle diameter of 1 μm or more and 13 μm or less is used as the main pigment, the surface of the ink receiving layer is not glossy and a mat type ink jet recording material is obtained.

  Ink jet recording material having gloss when it has a layer containing a fine pigment having an average particle size of 0.01 to 1 μm, preferably a fine pigment of 0.01 to 0.5 μm as a main pigment, as the pigment constituting the ink receiving layer Therefore, it is preferable. When the ink receiving layer has two or more layers, a fine pigment having an average particle size of 0.01 to 1 μm may be included in all layers, but a pigment having a particle size larger than the upper layer in the lower layer, It is preferable to provide a layer containing a fine pigment having an average particle diameter of 0.01 to 1 μm because the lower layer absorbs a lot of ink solvent.

  As a fine pigment having an average particle size of 0.01 to 1 μm suitable for an ink receiving layer or an upper layer of an ink receiving layer, a colloid of wet method silica produced by condensing gas phase method silica, mesoporous silica and activated silicic acid It is preferable to use at least one selected from the group of materials, alumina oxide, and alumina hydrate. Among these, gas phase method silica and alumina oxide are preferably selected. Among the alumina oxides, gas phase method (fumed) alumina oxide is preferable.

  Vapor phase silica is also called fumed silica, and is generally made by flame hydrolysis. Specifically, a method of making silicon tetrachloride by burning with hydrogen and oxygen is generally known, but silanes such as methyltrichlorosilane and trichlorosilane can be used alone or silicon tetrachloride instead of silicon tetrachloride. Can be used in a mixed state.

Mesoporous silica is a porous silica material having an average pore diameter of 1.5 to 100 nm. In addition, mesoporous silica into which aluminum, titanium, vanadium, boron, manganese atoms or the like are introduced can also be used. The physical properties of the porous body are not particularly limited, but the BET specific surface area (nitrogen adsorption specific surface area) is preferably 200 to 1500 m ² / g, and the pore volume is preferably 0.5 to 4 cc / g. The method for synthesizing mesoporous silica is not particularly limited, but is described in U.S. Pat. No. 3,556,725, in which a quaternary ammonium salt containing a long-chain alkyl is used as a template. Hydrothermal synthesis method using amorphous silica powder or alkaline silicate aqueous solution described in Table 5-5503499 etc. as a silica source and using a quaternary ammonium salt having a long chain alkyl group or a phosphonium salt as a template, A method of synthesizing a layered silicate such as kanemite as a silica source described in Kaihei 4-238810, etc. by an ion exchange method using a long-chain alkylammonium cation as a template, further dodecylamine, hexadecylamine, etc. Amines, nonionic surfactants, etc. As the template, it is as a source of silica and water glass or the like and a method of synthesis using an active silica obtained by ion exchange. Examples of the method for removing the template from the nanoporous silica precursor include a method of baking at a high temperature and a method of extracting with an organic solvent.

  The wet-process silica colloid produced by condensing activated silicic acid is obtained by adding an alkali to a colloidally dispersed silica seed solution, and at least selected from an aqueous solution of active silicic acid and alkoxysilane. It is a secondary silica dispersion obtained by growing silica fine particles by adding one kind of feed solution little by little, and can be obtained by a method described in, for example, JP-A-2001-354408.

  Alumina oxide is also generally called crystalline alumina oxide having crystallinity. Specific examples include alumina oxide having χ, κ, γ, δ, θ, η, ρ, pseudo γ, and α crystals. In the present invention, gas phase method alumina oxide and alumina oxide having γ, δ, and θ crystals are preferably selected from the viewpoint of gloss and ink absorbability. Vapor phase alumina oxide (fumed alumina) having a sharp particle size distribution and particularly excellent film formability is most preferred.

  Vapor phase alumina oxide is alumina formed by high temperature hydrolysis of gaseous aluminum trichloride, resulting in the formation of high purity alumina particles. The primary particle size of these particles is nano-order, and shows a very narrow particle size distribution (particle size distribution). Such vapor phase alumina oxide has a cationic surface charge. The use of vapor phase alumina oxide in ink jet coating is shown, for example, in US Pat. No. 5,171,626.

  The alumina hydrate is not particularly limited, but boehmite or pseudoboehmite is preferably selected from the viewpoint of ink absorption speed and film formability. The production method of alumina hydrate includes, for example, a method of hydrolyzing aluminum isopropoxide with water (BE Yoldas, Amer. Ceram. Soc. Bull., 54, 289 (1975), etc.) and aluminum alkoxide. And the like (Japanese Patent Laid-Open No. 06-064918).

  As for the form of the fine pigment, an aggregated particle dispersion of the pigment is mainly preferably used for the purpose of obtaining high ink absorbability, coating film forming property, and smoothness. The average particle size is about 0.01 to 1 μm. From the viewpoint of the ink absorption rate and the like, an aggregate pigment having an average particle diameter of 0.01 to 0.7 μm formed by aggregating primary particles having an average primary particle diameter of 0.003 to 0.040 μm is more preferable. Average particles formed by agglomeration of primary particles having an average primary particle size of 0.005 to 0.020 μm in order to easily fix dyes and pigments in the ink and to obtain a high ink absorption rate, printing density, and gloss. A pigment having a diameter of 0.5 μm or less is more preferable.

  A pigment having an average particle size of 0.7 μm or less can be obtained by, for example, a strong force by mechanical means, that is, a so-called breaking down method (a method of fragmenting a bulk material). Mechanical means include: ultrasonic homogenizer, pressure homogenizer, liquid collision homogenizer, high-speed rotary mill, roller mill, container drive medium mill, medium agitator mill, jet mill, mortar, disintegrator (covered in a bowl-shaped container) A device for grinding and kneading the pulverized material with a bowl-shaped stirring bar), a sand grinder, and the like. In order to reduce the particle size, classification and repeated pulverization can be performed.

  The average particle diameter referred to in the present invention is, regardless of whether the pigment is powder or slurry, first, 200 g of a 3% pigment aqueous dispersion is prepared, and then stirred and dispersed at 1000 rpm for 30 minutes with a commercially available homomixer. Immediately observed with an electron microscope (SEM and TEM) (taken 10,000-400,000 times electron micrographs, measured and averaged the diameter of a 5 cm square particle, “Particle Handbook”, Asakura Bookstore, p52, 1991).

  In the present invention, an ink receiving layer having a pigment, an adhesive, and an ink fixing agent can be finished by a mirror drum. A method in which an ink receiving layer is applied and pressed onto a heated mirror drum while the coating layer is in a wet state and dried to finish (wet cast method), or after the coating layer is once dried and rewet, A method of press-contacting to a heated mirror drum, drying and finishing (rewet casting method), while in a wet state, after applying a gelling agent to gel the coating layer, press-contacting to a heated mirror drum, A method of drying and finishing (gelation cast method) is preferable because an ink jet recording body having excellent gloss and ink absorbability can be obtained. The temperature of the heated mirror drum is, for example, 50 to 150 ° C, preferably 70 to 120 ° C.

  Further, a coating liquid containing a resin and, if necessary, a pigment is directly applied to the heated mirror drum, and an ink receiving layer is provided while the coating layer is in a somewhat wet state. It is also possible to adopt a method (precast method) in which the substrate is pressed and dried to finish. Furthermore, while a coating liquid containing a resin and, if necessary, a pigment is coated on a smooth film or sheet, the coating layer or the ink receiving layer to be laminated is in a certain wet state. Further, a method (film transfer method) in which a smooth film or sheet is peeled and finished after being pressed and dried on the substrate can also be employed.

  The present invention also includes an ink receiving layer having a pigment, an adhesive, and an ink fixing agent, and a coating liquid containing a fine pigment having an average particle size of 0.05 μm or less is applied on the ink receiving layer. It is also possible to obtain an ink jet recording material having an outermost layer formed by pressure-bonding to a heated mirror drum while in a wet state. The outermost layer is configured to contain a resin. The outermost layer is preferably porous or liquid-permeable so long as it does not impair the gloss so that the ink can pass or absorb quickly. In order to do this, it is preferable to select a drying condition in which the resin is not completely formed as long as the pigment is blended or the gloss is not lowered.

The pigment used for the outermost layer can be the same as that used for the ink receiving layer, but in terms of gloss, transparency and ink absorbability, colloidal silica, amorphous silica, aluminum oxide, zeolite, synthetic smectite. Etc. are preferable. These pigments are desirably contained in an amount of 10 to 80% by mass in the coating layer. The greater the BET specific surface area of the pigment, the better the ink absorbency. Therefore, 150 m ² / g or more is preferable. Although there is no particular upper limit, for example, a pigment of about 1000 m ² / g is available.
The average particle diameter of the pigment is preferably from 0.01 to 5 μm, more preferably from 0.05 to 1 μm. When the particle diameter is less than 0.01 μm, the effect of improving ink absorbency is poor, and when it exceeds 5 μm, there is a possibility that the gloss and the print density are lowered. In particular, when silica fine particles having an average particle diameter of 3 nm to 40 nm and a secondary particle average particle diameter of 10 nm to 300 nm are used as the pigment, the gloss and ink absorbability are particularly excellent. It is particularly preferred when the glossy layer is formed with the pigment as the main component (10-80%). In this case, since the gloss layer is excellent in ink absorption and transparency, when a cationic compound is blended in the gloss layer, the ink dye is efficiently fixed on the gloss layer, and the print density is extremely excellent combined with the transparency of the gloss layer. It is easy to become a thing.

  Examples of the outermost layer resin include organic polymers, particularly polyvinyl alcohols, aqueous urethane resins, and polymer resins obtained by polymerizing monomers having an ethylenically unsaturated bond. The aqueous urethane resin is obtained by reacting isocyanates such as diisocyanate, triisocyanate, and tetraisocyanate with polyols. In particular, a polymer composition obtained by polymerizing a monomer having an ethylenically unsaturated bond (hereinafter referred to as an ethylenic monomer) is preferably used. Examples of such a polymer include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, 2-hydroxyethyl methacrylate, glycidyl acrylate, etc. alkyl ester having 1 to 18 carbon atoms, methyl methacrylate, ethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, Methacrylic acid ester having 1-18 alkyl groups such as glycidyl methacrylate, styrene, α-methylstyrene, vinyl toluene, acrylonitrile, vinyl chloride, vinyl chloride Emissions, vinyl acetate, vinyl propionate, acrylamide, N- methylol acrylamide, ethylene, butadiene, acrylic acid, ethylenic monomers polymerized to obtain a polymer, such as methacrylic acid.

  The polymer may be a copolymer in which two or more kinds of ethylenic monomers are used in combination as necessary, or may be a substituted derivative of these polymers or copolymers. In addition, the above ethylenic monomer is polymerized in the presence of colloidal silica to form a composite with a Si—O—R (R: polymer component) bond, or the polymer or copolymer has a SiOH group, etc. It is also possible to introduce a functional group capable of reacting with the colloidal silica and use it in the form of a composite by reacting with the colloidal silica. When this composite is used, it tends to be excellent in gloss and ink absorbability, and is likely to be excellent in releasability from the cast drum again using the cast method described later. The composite particles are not particularly limited, but for example, the average particle diameter is about 30 to 150 nm.

  The (co) polymer preferably has a glass transition point of 40 ° C. or higher, more preferably in the range of 50 to 100 ° C. When the glass transition point is low, film formation proceeds too much during drying, and the surface porosity is lowered, and the ink absorption rate may be lowered. Also, the drying temperature is important. If the drying temperature is too high, the film formation proceeds too much, the surface porosity decreases, the ink absorption rate decreases, and conversely, if the drying temperature is too low, the gloss tends to be poor. And productivity is reduced. The glossy layer can be applied with a coating liquid composed mainly of a resin and, if necessary, a pigment as a main component on the coating layer, and can be appropriately smoothed by a super calender or the like.

The outermost layer is coated with a coating liquid composed mainly of a resin and, if necessary, a pigment, and pressed and dried to a heated mirror drum while the coating layer is in a wet state. The method (wet cast method), or the method of drying and rewetting the coating layer once, and then press-contacting and drying to a heated mirror drum (rewet cast method) is an ink jet that combines excellent gloss and ink absorption This is preferable because a recording sheet can be obtained. The temperature of the heated mirror drum is, for example, 50 to 150 ° C, preferably 70 to 120 ° C.
Further, a coating liquid containing a resin and, if necessary, a pigment is directly applied to the heated mirror drum, and an ink receiving layer is provided while the coating layer is in a somewhat wet state. It is also possible to adopt a method (precast method) in which the substrate is pressed and dried to finish. Furthermore, while a coating liquid containing a resin and, if necessary, a pigment is coated on a smooth film or sheet, the coating layer or the ink receiving layer to be laminated is in a certain wet state. It is also possible to employ a method (film transfer method) in which a smooth film or sheet is peeled and finished after being pressed and dried on the substrate.
In the coating composition for the glossy layer, pigments, antifoaming agents, colorants, antistatics used in general printing coated paper and inkjet paper are used to adjust the whiteness, viscosity, fluidity, etc. Various auxiliary agents such as a preservative, a preservative, a dispersant, and a thickener can be added as appropriate. Moreover, it is possible to mix | blend a cationic resin and to provide ink dye fixing property also to the outermost layer.

When the above-mentioned outermost layer coating liquid is applied onto the ink receiving layer, various known methods such as a blade coater, an air knife coater, a roll coater, a brush coater, a champlex coater, a bar coater, a gravure coater, a die coater curtain coater, etc. The coating device can be used. After that, preferably, while the coating layer is in a wet state as described above, or once dried and re-wet, it is pressed against a heated mirror drum and dried to perform a cast finish. The coating amount of the gloss layer coating liquid in this case is 0.2 to 30 g / m ² , preferably 1 to 10 g / m ² in terms of dry solid content. Here, if it is less than 0.2 g / m ² , gloss may not be sufficiently obtained. If it exceeds 30 g / m ² , the ink drying property may be deteriorated or the recording density may be lowered. After the outermost layer is provided, a smoothing process can also be performed using a super calendar or the like. It is also possible to provide only one ink-receiving layer that can also serve as the outermost layer on the base material and finish it by the casting method to obtain a cast-type ink jet recording paper. In this case, the pigment described above with respect to the outermost layer is preferably used.

  In the case of a glossy type ink jet recording material, the present invention also forms a microporous layer obtained by thickening or gelling the ink receiving layer coating solution simultaneously with or after coating and drying. It is preferable to do. There is no particular limitation on the method for thickening or gelling the ink receiving layer coating solution simultaneously with or after coating. For example, (a) thickening or gelation by using a crosslinking agent capable of crosslinking reaction with a hydrophilic binder blended in the recording layer, (b) thickening or gelling by supplying energy such as electron beam Examples of the method include (c) a hydrophilic binder, a thermosensitive polymer compound that exhibits hydrophilicity and hydrophobicity depending on temperature conditions, and a method of increasing the viscosity or gelation by changing the temperature.

  (A) As a method of thickening or gelating using a crosslinking agent capable of crosslinking reaction with the hydrophilic binder blended in the recording layer, the exemplified hydrophilic binder and the crosslinking agent capable of crosslinking reaction with the hydrophilic binder. Are used in combination. For example, a recording layer coating solution is prepared by coating and impregnating a base material with a crosslinking agent in advance and then applying a recording layer coating solution. After the application, it may be produced by a method of applying a cross-linking agent. However, it is preferable to apply the cross-linking agent in advance because a recording layer with uniform thickening or gelation can be obtained.

  Examples of the crosslinking agent include a boron compound, an epoxy compound, a glycidyl compound, a zirconium compound, an aluminum compound, a chromium compound, and the like. Among these, a boron compound is particularly preferable because thickening or gelation occurs quickly.

The boron compound is an oxygen acid having a boron atom as a central atom and a salt thereof. Examples include orthoboric acid, metaboric acid, hypoboric acid, tetraboric acid, pentaboric acid, and their sodium, potassium, and ammonium salts. Among these, orthoboric acid and disodium tetraborate are preferably used because they have an effect of moderately thickening the paint.
Although content of a boron compound is based also on the kind of boron compound and a hydrophilic binder, it is preferable to contain 0.01-1.5 g / m < ² > on the single side | surface of a base material. When the amount is more than 1.5 g / m ² , the crosslinking density with the hydrophilic binder increases, the coating film becomes hard and is easily broken. On the other hand, when the amount is less than 0.01 g / m ² , the crosslinking with the hydrophilic binder is weak, the gelation of the paint is weakened, and the coating film is easily cracked.

  (B) As a method of increasing the viscosity or gelation by supplying energy such as an electron beam, the recording layer binder does not have a radical polymerizable unsaturated bond, and the aqueous solution is irradiated with an electron beam. By using a hydrophilic binder that forms a hydrogel, a coating liquid containing 1 to 100 parts by weight of a hydrophilic binder is applied to 100 parts by weight of the fine pigment, and then irradiated with an electron beam. It is preferable to form the recording layer by hydrolyzing the applied coating solution and then drying it.

  Examples of the hydrophilic binder that does not have a radical polymerizable unsaturated bond and forms a hydrogel by irradiating an aqueous solution with an electron beam include, for example, polyvinyl alcohol, polyethylene oxide, polyalkylene oxide, polyvinyl pyrrolidone, water-soluble Polyvinyl acetal, poly-N-vinylacetamide, polyacrylamide, polyacryloylmorpholine, polyhydroxyalkyl acrylate, polyacrylic acid, hydroxyethylcellulose, methylcellulose, hydroxypropylmethylcellulose, hydroxypropylcellulose, gelatin, casein, and water-soluble derivatives thereof, Moreover, these copolymers etc. can be illustrated and it is good to use these individually or in combination.

  As the electron beam irradiation method, for example, a scanning method, a curtain beam method, a broad beam method, or the like is adopted, and an acceleration voltage at the time of irradiation with an electron beam is appropriately about 50 to 300 kV. The amount of electron beam irradiation is preferably adjusted in the range of about 1 to 200 kGy. If it is less than 1 kGy, it is not sufficient to gel the coating layer, and irradiation exceeding 200 kGy is not preferable because it may cause deterioration or discoloration of the substrate or the coating layer.

  (C) As a hydrophilic binder, a temperature-sensitive polymer compound that exhibits hydrophilicity and hydrophobicity depending on temperature conditions is used. As a method of thickening or gelling by changing the temperature, as the binder, It is preferable to use a temperature-sensitive polymer compound that exhibits hydrophilicity in the temperature range and exhibits hydrophobicity in the temperature range higher than the temperature-sensitive point.

  When this thermosensitive polymer compound is used, coating is performed at a temperature higher than the temperature sensitive point, and by cooling to a temperature lower than the temperature sensitive point, the applied layer is thickened or gelled and then dried. A recording layer may be formed. Examples of such temperature-sensitive polymer compounds include those disclosed in JP-A-2003-40916, which are obtained by polymerization in the presence of polyvinyl alcohol and / or polyvinyl alcohol derivatives. it can.

  The ink receiving layer coating solution prepared as described above is applied by, for example, the following method. Before the recording layer becomes a reduced rate drying part (indicating a reduced rate drying rate), it is formed by thickening or gelling (for example, thickening or gelling the coating liquid with a crosslinking agent such as a boron compound). . This has a great effect of preventing the coating layer from cracking due to hot air during drying by thickening or gelling the coating in the early stage of drying and preventing the coating from penetrating into the substrate. In particular, when a thermosensitive polymer compound is used and the coating liquid is gelled by cooling, cracking does not occur, which is particularly preferable.

The coating amount of the ink receiving layer coating solution is not particularly limited, but is about 5 to 40 g / m ² , preferably 7 to 30 g / m ² . If the coating amount is small, the recent high-speed and high-speed printer may have insufficient ink absorption speed, and if it is too large, it is difficult to control cracks in the coating film.
From the balance between the ink absorption speed and the ink absorption capacity, the coating amount of the recording layer is preferably at least three times the outermost layer coating amount described later. 7 times or more is more preferable, and 10 to 60 times is the most preferable range.

  As a coating apparatus for applying the ink receiving layer coating liquid, a coating method of a pre-measurement method is preferable from the viewpoint of the physical properties of the paint and the coating amount. Examples of the pre-measuring method include various known methods such as lip coaters, curtain coaters, slide beads, slide hoppers, and die coaters such as slot dies. Moreover, when applying two or more layers, it is preferable to apply by Wet on Wet (method to apply the upper layer on the lower layer while the lower layer is not dried).

  The method for drying the ink receiving layer of the present invention is not particularly limited. A drying device conventionally used in a coating machine can be used.For example, various heating drying methods such as hot air drying, gas heater drying, high-frequency drying, electric heater drying, infrared heater drying, and laser drying are preferable and used as appropriate. The Of these, hot air drying is preferred because it is advantageous in terms of cost. It is also possible to finish the outermost layer with a mirror drum to give high gloss.

  The present invention will be described more specifically with reference to the following examples, but of course is not limited to these examples. In addition, the number of parts and% shown in an Example mean a mass part and mass%.

(Preparation of undercoat layer coating solution)
A dispersion in which 100 parts of kaolin (trade name: UW90, manufactured by Engelhard Co., Ltd.) is dispersed, and a styrene / butadiene latex (trade name: Nipol LX407F, manufactured by Nippon Zeon Co., Ltd.) 10% aqueous solution 200 as a binder. The undercoat layer coating solution was prepared by mixing the parts.

(Preparation of ink receiving layer coating solution)
100 parts of amorphous silica (trade name: Fine Seal X-37, manufactured by Tokuyama Co., Ltd., BET specific surface area 260 m ² / g, average particle size 2.8 μg) was replaced with a cationic resin (trade name: Unisense CP-103, Senka Industries). Ink by mixing 250 parts of a 10% aqueous solution of a 10% aqueous solution (made by Co., Ltd.) and 250 parts of a 10% aqueous solution of modified polyvinyl alcohol (trade name: Kuraray Poval R1130, made by Kuraray Co., Ltd.) as a binder. A receiving layer coating solution was prepared.

(Preparation of gloss layer coating solution 1)
100 parts of a composite of styrene-2-methylhexyl acrylate copolymer and colloidal silica (trade name: Movinyl 8055, manufactured by Hoechst Synthetic Co., Ltd.), alkyl vinyl ether / maleic acid derivative copolymer (thickening, dispersing agent) 5 parts Then, 3 parts of lecithin (release agent) were mixed to prepare a coating solution 1 for glossy layer.

"Preparation of cationic fine pigment"
Commercially available vapor phase silica (trade name: Leolosil QS-30, average primary particle size 9 nm, specific surface area 300 m ² / g, manufactured by Tokuyama Corporation) was dispersed and pulverized with a sand grinder, then nanomizer (trade name: Nanomizer, Using a nanomizer), pulverization and dispersion were repeated, and after classification, a 10% dispersion having an average secondary particle diameter of 80 nm was prepared.
10 parts of diallyldimethylammonium chloride-acrylamide copolymer (trade name: PAS-J-81, manufactured by Nitto Boseki Co., Ltd.) is added as a cationic compound to the dispersion to agglomerate the pigment and increase the dispersion. After causing viscosity, pulverization and dispersion were repeated using a nanomizer again to prepare an 8% dispersion liquid having an average secondary particle diameter of 300 nm to obtain a cationic fine pigment.

(Preparation of glossy layer coating solution 2)
100 parts of the above cationic fine pigment, 20 parts of thermosensitive polymer compound (ALB-8.01, manufactured by Asahi Kasei Co., Ltd., temperature sensitive point 15 ° C., glass transition temperature 90 ° C.), 5 parts of stearamide, defoaming Gloss layer coating solution 2 was prepared by mixing 0.1 part of the agent. In addition, the temperature at the time of mixing each material was 40 degreeC.

Example 1
(Preparation of paper support)
Canadian Standard Freeness (hereinafter abbreviated as CSF) 450 parts LBKP 90 parts and dried so that the moisture content of the fiber is 4.0% or less, maintained for 24 hours, then wet again Add 10 parts of LBKP adjusted to 450 ml of CSF, add 23 parts of kaolin and 0.01 part of a retention agent as a filler, then add 0.2 part of a modified rosin sizing agent and add 150 g / m ^{2 on} a long net paper machine. After making high-quality paper, a surface sizing liquid composed of a modified starch having a concentration of 2% was size-pressed so as to have an adhesion amount of 40 ml / m ² to obtain a paper support. The ash content of this paper support was 15%. The schiecht sizing degree converted to 100 g / m ² was 75 seconds.

(Preparation of inkjet recording material)
Using the obtained paper support, coating the ink receiving layer coating liquid on one side thereof so that the tension applied to the paper support is 30 kg / m, and the coating amount after drying is 20 g / m ² . After drying, a super calendar process (linear pressure 50 kg / cm, paper feeding speed 5 m / min) was performed to obtain an ink jet recording material.

Example 2
(Preparation of paper support)
The fiber was dried so that the moisture content in the fiber was 4.0% or less, maintained for 24 hours, and then again wetted to 100 parts of LBKP adjusted to 450 ml of CSF, 23 parts of kaolin as a filler, 0% of the retention agent. Add .01 parts, then add 0.2 parts of modified rosin sizing agent and make 150 g / m ² high-quality paper on a long paper machine, then attach a surface sizing solution consisting of modified starch with a concentration of 2% Size-pressing was performed so that the amount was 40 ml / m ² to obtain a paper support. The ash content of this paper support was 15%. The schiecht sizing degree converted to 100 g / m ² was 75 seconds.

(Preparation of inkjet recording material)
An ink jet recording material was obtained in the same manner as in Example 1 except that the obtained paper support was used.

Example 3
(Preparation of paper support)
In the production of the paper support of Example 1, a paper support was produced in the same manner as in Example 1 except that 0.2 parts of a polyamine / epichlorohydrin wet paper strength enhancer was further added. The ash content of this paper support was 15%. The schiecht sizing degree converted to 100 g / m ² was 78 seconds.

(Preparation of inkjet recording material)
An ink jet recording material was obtained in the same manner as in Example 1 except that the obtained paper support was used.

Example 4
(Preparation of paper support)
Canadian standard freeness (hereinafter abbreviated as CSF) 250 ml of LBKP and 90 parts of fiber were dried so that the moisture content of the fiber was 4.0% or less, maintained for 24 hours, and then wetted again. 10 parts of LBKP adjusted to 450 ml of CSF, 23 parts of kaolin and 0.01 part of a retention agent are added as a filler, then 0.2 part of a modified rosin sizing agent is added, and a long net paper machine is used to add 150 g / m ² . After making high-quality paper, a surface sizing liquid composed of a modified starch having a concentration of 2% was size-pressed so as to have an adhesion amount of 40 ml / m ² to obtain a paper support. The ash content of this paper support was 15%. The schiecht sizing degree converted to 100 g / m ² was 75 seconds.

(Preparation of inkjet recording material)
An ink jet recording material was obtained in the same manner as in Example 1 except that the obtained paper support was used.

Comparative Example 1
In the production of the paper support of Example 1, a paper support was obtained in the same manner as in Example 1 except that the modified rosin sizing agent was added in an amount of 0.01 part. The ash content of this paper support was 15%. The schiecht sizing degree converted to 100 g / m ² was 10 seconds.

(Preparation of inkjet recording material)
An ink jet recording material was obtained in the same manner as in Example 1 except that the obtained paper support was used.

Comparative Example 2
In the production of the paper support of Example 1, a paper support was obtained in the same manner as in Example 1 except that the blend of the modified rosin sizing agent was 0.35 part. Is the ash content of this paper support 15? %Met. The schiecht sizing degree converted to 100 g / m ² was 200 seconds.

(Preparation of inkjet recording material)
An ink jet recording material was obtained in the same manner as in Example 1 except that the obtained paper support was used.

Comparative Example 3
Canadian standard freeness (hereinafter abbreviated as CSF) 450ml LBKP 100 parts, kaolin 23 parts, filler 10 parts, and then rosin size 0.2 parts Then, after making a high-quality paper of 150 g / m ^2, the surface size liquid made of modified starch having a concentration of 2% was size-pressed so as to have an adhesion amount of 40 ml / m ² to obtain a paper support. Is the ash content of this paper support 15? %Met. The schiecht sizing degree converted to 100 g / m ² was 75 seconds.

(Preparation of inkjet recording material)
An ink jet recording material was obtained in the same manner as in Example 1 except that the obtained paper support was used.

Example 5
(Preparation of inkjet recording material)
Using the paper support obtained in Example 1, using the ink-receiving layer coating liquid on one side, the tension applied to the paper support is 30 kg / m, and the coating amount after drying is 20 g / m ^2. After coating and drying, an ink receiving layer was formed by performing a super calender process (linear pressure 50 kg / cm, paper passing speed 5 m / min).
Next, after the gloss layer coating liquid 1 is further coated on the ink receiving layer using a roll coater, it is immediately pressed against a mirror drum having a surface temperature of 85 degrees, dried and released, and cast type gloss inkjet. A record was obtained.

Comparative Example 4
(Preparation of inkjet recording material)
Using the paper support obtained in Comparative Example 1, using the ink-receiving layer coating liquid on one side, the tension applied to the paper support is 30 kg / m, and the coating amount after drying is 20 g / m ^2. After coating and drying, an ink receiving layer was formed by performing a super calender process (linear pressure 50 kg / cm, paper passing speed 5 m / min).
Next, after the gloss layer coating liquid 1 is further coated on the ink receiving layer using a roll coater, it is immediately pressed against a mirror drum having a surface temperature of 85 degrees, dried and released, and cast type gloss inkjet. A record was obtained.

Example 6
(Preparation of inkjet recording material)
Using the paper support obtained in Example 1, using the ink-receiving layer coating liquid on one side, the tension applied to the paper support is 30 kg / m, and the coating amount after drying is 20 g / m ^2. After coating and drying, an ink receiving layer was formed by performing a super calender process (linear pressure 50 kg / cm, paper passing speed 5 m / min).
Next, the gloss layer coating liquid 2 is further coated on the ink receiving layer using an air knife coater at a coating liquid temperature of 25 ° C. so as to have an absolutely dry mass of 6 g / m ² , followed by cold air. The coating liquid was gelled by cooling using a machine until the temperature reached 10 ° C. Subsequently, while the coating layer was in a wet state, it was pressed against a mirror drum having a surface temperature of 90 ° C. and dried to obtain an ink jet recording material.

Example 7
(Preparation of inkjet recording material)
Using the paper support obtained in Example 1, using the ink-receiving layer coating liquid on one side, the tension applied to the paper support is 30 kg / m, and the coating amount after drying is 20 g / m ^2. After coating and drying, an ink receiving layer was formed by performing a super calender process (linear pressure 50 kg / cm, paper passing speed 5 m / min).
Next, the gloss layer coating liquid 2 is further coated on the ink receiving layer using a roll coater at a coating liquid temperature of 25 ° C. so as to have an absolutely dry mass of 3 g / m ^2. Without lowering the temperature, the ink-jet recording material was obtained by press-contacting and drying on a mirror drum having a surface temperature of 90 ° C. while the coating layer was in a wet state.

Example 8
(Preparation of inkjet recording material)
Using the paper support obtained in Example 1, using the ink-receiving layer coating liquid on one side, the tension applied to the paper support is 30 kg / m, and the coating amount after drying is 20 g / m ^2. After coating and drying, an ink receiving layer was formed by performing a super calender process (linear pressure 50 kg / cm, paper passing speed 5 m / min).
Next, the gloss layer coating liquid 2 is further coated on the ink receiving layer using a bar coater at a coating liquid temperature of 25 ° C. so as to have an absolutely dry mass of 6 g / m ² , followed by a cooling device. The solution was cooled until the temperature reached 10 ° C. to gel the coating solution. Subsequently, hot air of 90 ° C. was blown through the coating layer and dried to obtain an ink jet recording material.

Example 9
(Preparation of inkjet recording material)
Similar to Example 1 except that the paper support obtained in Example 1 was used, and the undercoat layer coating solution was coated on both sides so that the coating amount after drying was 20 g / m ² and dried. An ink jet recording material was produced.

  Evaluation of the degree of elongation in water, the degree of Steecht's size and the Gurley stiffness of the support for the ink jet recording body (paper support) thus obtained, the suitability of ink jet recording for the ink jet recording body, and after printing The evaluation of the cockling was performed by the following method and summarized in Table 1.

[Underwater elongation]
JAPAN TAPPI Paper Pulp Test Method No. Based on the 27-B method, the elongation in water in the CD direction of the support for an inkjet recording medium was measured.

[Stick human sizing degree]
Based on the JIS P 8122 method, the measurement of the degree of sticky sizing (converted to 100 g / m ² ) of the support for an inkjet recording medium was performed.

[Gurley stiffness]
In accordance with the JAPAN TAPPI paper pulp test method N0.40 method, the stiffness of the support for an inkjet recording medium was measured in an environment of 30 ° C. and 80% RH.

[Inkjet recording suitability]
Printing was performed using an ink jet printer PM970C (manufactured by Seiko Epson Corporation).

(Printing blur)
Black, cyan, magenta, and yellow solid prints were made so that the borders touched each other, and the blurring at the borders was visually evaluated.
(Double-circle): A blemishes is not seen but is a favorable level.
○: There are slight blemishes, but there is no practical problem.
Δ: Slightly noticeable blistering and slightly problematic in practical use.
×: Level of serious blurring and a serious problem in practical use

(Cockling)
The cockling situation one day after printing was visually evaluated.
○: The occurrence of cockling is not observed, which is good.
X: Cockling occurs and is a problem level.

By using the support for an ink jet recording body of the present invention, it is possible to obtain an ink jet recording body that records high-definition images with good reproducibility with little blur after printing and no occurrence of cockling even in full-color printing. it can. Further, it is possible to provide a high-quality ink jet recording material without subjecting the paper support to lamination.

Claims (8)

In a support for an ink jet recording body having an ink receiving layer for recording with an ink for ink jet recording on at least one side,
The support is a paper whose main component is pulp that does not have a laminate layer of thermoplastic resin; TAPPI No. The elongation in water in the CD direction measured by 27-B is 2.0% or less, the Steecht sizing degree when converted to a basis weight of 100 g / m ² is 20 seconds or more and 150 seconds or less, and 30 ° C. In an environment of 80% RH, TAPPI Paper Pulp Test Method No. 40. A support for an inkjet recording medium, wherein the Gurley stiffness in the CD direction measured according to 40 is 2.5 mN or more. The support for an ink jet recording material according to claim 1, wherein the pulp includes dry pulp and / or recycled pulp that has undergone a drying history. The support for an ink jet recording material according to claim 2, comprising 5% or more of the total pulp and dry pulp and / or recycled pulp having undergone a drying history. An ink jet recording body comprising at least one ink receiving layer having a pigment, an adhesive, and an ink fixing agent on one side of the support for an ink jet recording body according to claim 1. An ink receiving layer having at least one pigment, an adhesive, and an ink fixing agent is provided on one side of the support for an inkjet recording medium according to any one of claims 1 to 3, and an average particle is formed on the ink receiving layer. An ink jet recording material having a glossy layer containing a pigment having a diameter of 0.5 μm or less. An ink receiving layer having a pigment, an adhesive, and an ink fixing agent is provided on one side of the support for an inkjet recording body according to any one of claims 1 to 3, and the surface of the ink receiving layer is finished by a mirror drum. Inkjet recording material. An ink receiving layer having a pigment, an adhesive, and an ink fixing agent is provided on one side of the support for an inkjet recording body according to any one of claims 1 to 3, and an average particle diameter is provided on the ink receiving layer. An ink jet recording material having an outermost layer formed by applying a coating liquid containing a fine pigment of 0.05 μm or less and press-bonding to a heated mirror drum while in a wet state. The ink jet recording material according to any one of claims 4 to 7, wherein the adhesive of the ink receiving layer is a thermosensitive polymer compound that reversibly exhibits hydrophilicity and hydrophobicity depending on temperature.