JP6426995B2 - Ink jet recording medium - Google Patents

Description

  The present invention relates to an inkjet recording medium.

  The ink jet recording method is a method of recording by forming dots by discharging ink droplets and depositing them on a recording paper. In recent years, with technological advances in ink jet printers, inks, and recording media, high-quality printing has become possible. As a medium dedicated to such inkjet recording, a paper and / or film is used as a support, and a medium having a pigment coating layer mainly composed of a pigment and a binder (so-called void type medium) or a resin coating layer containing no pigment A medium provided on the surface (so-called swelling medium) is often used.

  On the other hand, not only dye inks using dye colorants that have been the mainstream of ink jet inks, but also pigment inks in which color pigments having excellent storage properties such as water resistance and light resistance are dispersed are used for ink jet printer inks It has become. Since the absorption speed of pigment ink is slower than dye ink, the ink receiving layer must have pores of the appropriate size, and even with an ink receiving layer excellent in dye ink suitability, the pigment ink absorbability is poor and color development is deteriorated. There are many things to do.

  In addition, the technology of the ink jet printer is used not only in personal printers for home use but also in fields such as commercial printing where digitalization of variable information is performed at high speed. That is, in recent years, in the field of commercial printing, a so-called on-demand printing method is being introduced, and many inkjet printers adopting the on-demand printing method have appeared. The on-demand printing method is also suitable for printing a small number of copies because it can directly print information on a medium such as paper without making a plate.

  Not only printers for personal use, but also ink jet printers using an on-demand printing method can use dye ink and pigment ink properly depending on applications. As described above, it is not easy to design an ink receiving layer that can print both inks satisfactorily because both inks are different from each other. However, separately supplying a medium having an ink receiving layer suitable for both inks separately is extremely uneconomical for the users of various ink jet printers. In order to meet the needs of these users, it is necessary to have a simple means for ink receiving layer design that does not require major changes in the basic design of the conventional ink receiving layer.

  As such an ink jet recording medium, Patent Document 1 discloses that a stain is generated in a calender process by containing a cationic substance and a lubricant in an ink receiving layer containing a pigment and a styrene butadiene latex. Therefore, it is possible to suppress the deterioration of the feeling of white space due to it, and further, it has been proposed to provide an inkjet printing paper with high print quality while maintaining the same texture as a coated paper for general printing.

  However, with the technology described in Patent Document 1, while it is possible to reduce stains in the calender process and to obtain an inkjet printing sheet with good print quality by dye ink and print quality by pigment ink, it is possible for coated layers In some cases, the final product of the ink jet printing paper may be damaged in the feel of the coating layer (hereinafter also referred to as white space) due to the aggregates formed in the coating liquid.

JP 2014-205270

  Therefore, an object of the present invention relates to an ink jet recording medium, which has print aptitude (ink absorbability and color developability) by dye ink and pigment ink, and is less contaminated with paint aggregates which become foreign matter in the ink receiving layer, white It is an object of the present invention to provide an ink jet recording medium with further improved paper feel.

  The ink jet recording medium according to the present invention is an ink jet recording medium obtained by providing an ink receiving layer containing a pigment and a binder on at least one surface of a support and carrying out a calender process, the ink receiving layer Is characterized by containing a lubricant, a surfactant and a water-soluble metal salt.

  In the inkjet recording medium according to the present invention, the surfactant is preferably nonionic. Excellent color development of pigment ink.

  In the inkjet recording medium according to the present invention, the water-soluble metal salt is preferably a water-soluble metal salt having two or more valences. Excellent color development of pigment ink.

  The present invention relates to an ink jet recording medium, and can provide a recording medium having printability with dye ink and pigment ink. Furthermore, according to the present invention, it is possible to provide an ink jet recording medium having a good feeling of white surface, with less contamination of paint aggregates which become foreign matter in the ink receiving layer. The ink jet recording medium of the present invention is particularly suitable as a recording medium for an ink jet printer for personal use and an ink jet printer adopting an on-demand printing method.

  EXAMPLES The present invention will next be described in detail by way of embodiments, which should not be construed as limiting the present invention. The embodiment may be variously modified as long as the effects of the present invention are exhibited.

  A film or paper can be used as a support used in this embodiment. Examples of the paper include high-quality paper, medium-grade paper, and white paperboard. Also, it is possible to use either acid paper or neutral paper. Pulp fibers used for paper (base paper) in the present embodiment are chemical pulp such as LBKP (hardwood kraft pulp), NBKP (softwood kraft pulp), GP (ground pulp), PGW (pressure ground pulp), RMP (Refiner mechanical pulp), TMP (thermomechanical pulp), CTMP (chemothermomechanical pulp), CMP (chemimechanical pulp), mechanical pulp such as CGP (chemi ground pulp), wood pulp such as DIP (deinked pulp) Non-wood pulp such as kenaf, bagasse, bamboo and cotton. These can be used alone or in combination in any proportion. In addition, synthetic fibers can be further blended as long as the effects of the present invention are not impaired. From the viewpoint of environmental conservation, pulp obtained from ECF (Elemental Chlorine Free) pulp or TCF (Totally Chlorine Free) pulp with low environmental impact, waste paper pulp, plantation trees is preferable. Moreover, it is preferable to make the pulp which comprises the base paper which concerns on this invention into the stock which has a freeness suitable as inkjet printing paper. A suitable freeness is, for example, 350 to 650 ml CSF at Canadian Standard Freeness (JIS P 8121: 1995 "Test Method for Freeness of Pulp"). Also, the film is not particularly limited, but, for example, a polyolefin film such as a polyethylene film or a polypropylene film can be used.

  In the paper, known fillers such as heavy calcium carbonate, light calcium carbonate, magnesium carbonate, titanium oxide, synthetic silica, alumina, talc, calcined kaolin clay, kaolin clay, bentonite, zeolite, aluminum hydroxide, zinc oxide, etc. Various paper making chemicals such as known paper strengthening agents, sulfuric acid bands, retention aids, sizing agents, dyes, fluorescent dyes and the like may be used appropriately. The method for preparing each stock, the method for blending, and the method for adding each paper making chemical are not particularly limited as long as the effects of the present invention are not impaired.

In addition, it is possible to make paper using a stock by applying a known paper making machine such as a cylinder paper machine, a fourdrinier paper machine, a twin wire paper machine, etc. Either single layer paper or multilayer paper may be used. . Furthermore, it is also possible to blend waste paper with the paper base, as long as the effects of the present invention are not impaired. Furthermore, in order to suppress excessive penetration of the coating liquid for the ink receiving layer, a known water-soluble polymer such as starch, polyvinyl alcohol, polyacrylamide or the like should be applied to the paper serving as the support with a size press or the like. Can. Although the basis weight of the paper used as a support is not particularly limited, it is preferably 30 to 300 g / m ^{2 in} consideration of the proper passing of the paper to the ink jet printer.

  The ink receiving layer contains a pigment and a binder as in the case of a general inkjet recording medium having a pigment coating layer. It does not specifically limit as a pigment used here, It is possible to use well-known pigments, such as a silica, an alumina, a clay, a calcium carbonate, a talc, and a titanium oxide. These may be used alone, or two or more may be used in combination as long as the effects of the present invention are not impaired.

  The binder used in the ink receiving layer is not particularly limited, and examples thereof include polyvinyl alcohol, polyvinyl acetal, starch, carboxymethyl cellulose, casein, gelatin, soybean protein, acrylic resin, urethane resin, styrene-acrylic resin, It is possible to use known binders such as polyester resins, vinyl polymer latexes such as styrene-butadiene copolymer latex, ethylene-vinyl acetate copolymer, and acrylic-silicone resins. One of these may be used alone, or two or more may be used in combination. Among these binders, it is preferable to use a polyvinyl alcohol or a styrene-butadiene copolymer latex because it is difficult to generate a paint aggregate to be described later. The amount of the binder used is not particularly limited and may be determined in consideration of the printability of the recording medium, the strength of the ink receiving layer, the surface gloss, the coating liquid properties, etc. It is preferable that it is the range of 1-100 mass parts with respect to a mass part. More preferably, it is 3 to 70 parts by mass, still more preferably 5 to 60 parts by mass, for example, 6 to 20 parts by mass. If the amount is less than 1 part by mass, the strength of the coated layer may decrease. When the amount is more than 100 parts by mass, the ink absorbability may be reduced.

  In the ink jet recording medium of the present invention, the ink receiving layer contains a water soluble metal salt. By containing the water-soluble metal salt, it is possible to suppress the bleeding of the inkjet ink and to obtain an inkjet recording medium having good printability by the dye ink and the pigment ink. As the water-soluble metal salt, it is preferable to use a water-soluble metal salt having a valence of 2 or more, because the color-forming property of the pigment ink is superior. Examples of the water-soluble metal salt having two or more valences are calcium salt, magnesium salt, aluminum salt, strontium salt, barium salt, zirconium salt, titanium salt and zinc salt. One of these may be used alone, or two or more may be used in combination. Furthermore, it is more preferable from the viewpoint of suppression of ink bleeding that the water-soluble metal salt having a valence of 2 or more is any one or more of a calcium salt and a magnesium salt. In the present invention, the water-soluble metal salt is a water-soluble metal salt of an inorganic acid such as hydrochloric acid, nitric acid, phosphoric acid or sulfuric acid and a water-soluble metal salt of an organic acid such as formic acid, acetic acid, citric acid or oxalic acid. Includes The content of the water-soluble metal salt in the ink receiving layer is preferably 0.1 to 50 parts by mass, and more preferably 0.3 to 40 parts by mass with respect to 100 parts by mass of the pigment. Alternatively, the content of the water-soluble metal salt in the ink receiving layer is preferably 0.05 to 30% by mass with respect to the dry mass of the ink receiving layer. More preferably, it is 0.1-25 mass%. More preferably, it is 0.5-20 mass%. If it is less than 0.05% by mass with respect to the dry mass of the ink receiving layer, the color developability of the pigment ink may be inferior. When it exceeds 30 mass% with respect to the dry mass of an ink receiving layer, there exists a possibility that the color development of dye ink may be inferior.

  In the ink jet recording medium of the present invention, in order to obtain a good feeling of white space, a support is provided with an ink receiving layer, and then calendering is performed. However, when the water-soluble metal salt is contained in the ink receiving layer, the surface of the calender roll tends to be easily stained when the calendering process is performed, causing a defect on the surface of the ink receiving layer, resulting in feeling of white space. It hurts Therefore, in the present invention, the ink receiving layer contains a lubricant. By containing a lubricant in the ink receiving layer, it is possible to suppress stains on the surface of the calender roll when the calender process is performed. In addition, the surface of the ink receiving layer becomes slippery and is less likely to be scratched. The lubricant used here is not particularly limited, and any of a liquid lubricant, a solidified product of the liquid lubricant, and a solid lubricant may be used. The lubricant is preferably added in an amount of 0.04 to 15% by mass, and more preferably 0.07 to 10% by mass, with respect to 100 parts by mass of the pigment. Alternatively, the lubricant is preferably added in an amount of 0.005 to 20% by mass with respect to the dry mass of the ink receiving layer. More preferably, it is 0.01-10 mass%. If the amount is less than 0.005% by mass with respect to the dry mass of the ink receiving layer, the effect of suppressing stains on the surface of the calender roll may be poor. When it exceeds 20% by mass with respect to the dry mass of the ink receiving layer, the color developability of the pigment ink may be inferior.

  As types of lubricants, higher fatty acid salts and / or polyethylene emulsions are preferred. Examples of higher fatty acid salts include laurate, oleate, palmitate, stearate and myristate (for example, sodium salts and potassium salts thereof, including so-called soaps) and lauric acid. Ammonium oleate, ammonium palmitate, ammonium stearate, ammonium myristate. In the present invention, the ink receiving layer preferably contains at least one of laurate, myristate and oleate as higher fatty acid salts. For example, as a higher fatty acid salt, a higher fatty acid salt insoluble in water is preferable from the viewpoint of maintenance of white paper gloss and suppression of stains on the surface of a calender roll, and an aqueous dispersion of calcium stearate, ammonium stearate It is more preferable to contain any one or more.

  Furthermore, a lubricant composed of wax or an organosilicon compound can be used. Waxes include vegetable waxes, animal waxes, montan waxes, paraffin waxes, synthetic waxes (hydrocarbon synthetic waxes, higher fatty acid esters, fatty acid amides, ketones / amines, hydrogen-cured oils, etc.), polypropylene and polytetrafluoroethylene It can be suitably selected from aliphatic hydrocarbons such as ethylene polymer and derivatives thereof. Examples of organosilicon compounds include polyalkylsiloxanes and derivatives thereof, dimethylsilicone, methylphenylsilicone oils, alkyl-modified silicone oils, alkyl / aralkyl-modified silicone oils, amino-modified silicone oils, polyether-modified silicone oils, higher fatty acid-modified silicone oils, It can be appropriately selected from low molecular weight and high molecular weight silicone oils such as carboxyl modified silicone oil, fluorine modified silicone oil, epoxy modified silicone oil, silicone rubber and the like.

  As described above, in the ink jet recording medium of the present invention, although the water-soluble metal salt and the lubricant are contained in the ink-receiving layer, the paint for the ink-receiving layer containing the water-soluble metal salt and the lubricant is prepared Then, the reason is not clear, but the stability with time of the paint is impaired, and even if dirt on the roll surface in the calender treatment is suppressed, aggregates may be generated in the paint over time. If aggregates are generated in the paint, foreign matter will eventually be mixed in the ink receiving layer, and as a result, the white space of the final product of the ink jet recording medium will be impaired.

  Therefore, in the present invention, a surfactant is contained in the ink receiving layer together with the water-soluble metal salt and the lubricant. By containing the surfactant, the temporal stability of the paint described above can be improved, and the generation of aggregates in the paint can be suppressed. The surfactant used here is, for example, an acetylene glycol surfactant, a perfluoroalkyl surfactant, a polyoxyethylene surfactant, or a silicone surfactant. One of these may be used alone, or two or more may be used in combination. The content of the surfactant is preferably in the range of 0.04 to 10 parts by mass, and more preferably 0.05 to 7 parts by mass with respect to 100 parts by mass of the pigment. Alternatively, the content of the surfactant is preferably 0.005 to 5% by mass with respect to the dry mass of the ink receiving layer. More preferably, it is 0.01 to 3% by mass. If it is less than 0.005 mass% with respect to the dry mass of an ink receiving layer, there exists a possibility that the inhibitory effect of generation | occurrence | production of the aggregate in a coating material may be scarce. When it exceeds 5 mass% with respect to the dry mass of an ink receiving layer, there exists a possibility that the color development of dye ink may be inferior. The surfactant is preferably a nonionic surfactant because it is excellent in the color-developing property of the pigment ink and is further excellent in the effect of suppressing the generation of aggregates in the paint.

  The ink receiving layer can also contain a cationic polymer as an ink fixing agent. The color developability of the dye ink can be further improved. The cationic polymer includes, for example, polyethyleneimine, epichlorohydrin modified polyalkylamine, polyamine, polyamine polyamide epichlorohydrin, dimethylamine ammonia epichlorohydrin, polyvinylbenzyltrimethylammonium halide, polydiacryldimethylammonium halide, polydimethylaminoethyl methacrylate hydrochloride, polyvinyl pyri Halide, cationic polyacrylamide, cationic polystyrene copolymer, diallyldimethyl ammonium chloride polymer, diallyldimethyl ammonium chloride sulfur dioxide copolymer, diallyl dimethyl ammonium chloride amide copolymer, dicyandiamide formalin polycondensate, dicyandiamide diethylene triamine Condensate, poly ant Amine, polydiallylamine, polyallylamine hydrochloride, polyacrylamide resin, polyamide epoxy resin, melamine resin acid colloid, urea resin, cationically modified polyvinyl alcohol, amino acid type amphoteric surfactant, betaine type compound, polyamidine compound, others 4 Grade ammonium salts, cationically modified polyurethane resins. One of these may be used alone, or two or more may be used in combination. In the present embodiment, the content of the cationic polymer is preferably 0.05 to 20% by mass with respect to the dry mass of the ink receiving layer. More preferably, it is 0.5-15 mass%.

  In the ink receiving layer, auxiliary agents such as dispersants, thickeners, preservatives, antifoaming agents, coloring dyes, coloring pigments, fluorescent whitening agents, water proofing agents, antioxidants, ultraviolet light absorbers and the like are appropriately added. It can be selected and blended.

  In the ink jet recording medium of the present invention, an ink receiving layer is provided on at least one surface of the support. The ink receiving layer can be obtained by applying an ink receiving layer paint to a support and then drying it. As a coating method of the coating liquid which forms the ink receiving layer, there are known coating machines such as an air knife coater, roll coater, reverse roll coater, bar coater, comma coater, blade coater, simultaneous multilayer coating machine and the like However, any may be used.

The coating amount (absolute dry mass) of the ink receiving layer is preferably ³ to 30 g / m ² per one side. More preferably, it is 4-25 g / m < ² >, More preferably, it is 5-20 g / m < ² >. If it is less than 3 g / m ² , the ink absorption may be poor. If it exceeds 30 g / m ² , the mechanical strength of the coated surface may be insufficient.

  After the ink receiving layer is coated, a calendering process such as a machine calender, a soft calender, a super calender and the like is performed to perform a smoothing process. Processing can be performed by appropriately adjusting processing conditions such as the pressure device configuration, the number of pressure nips, and the temperature condition at that time. For example, the calendering treatment may be performed under conditions of a temperature of 30 to 100 ° C. and a calendering linear pressure of 50 to 200 kg / cm.

  In the ink jet recording medium of the present invention, it is possible to provide one or more subbing layers mainly composed of a white pigment and a binder between the ink receiving layer and the support. It can be set as the medium for inkjet recording which is excellent by the absorbency of dye ink and pigment ink.

There are known coating machines such as an air knife, a roll coater, a bar coater, a comma coater, a blade coater, and a simultaneous multilayer coating machine as a coating method of the coating liquid for forming the undercoat layer. The coating amount (absolute dry mass) of the undercoat layer which may be used is not particularly limited. However, if the coating amount is too small, the ink absorbability may be poor, so 5 g / solid side in terms of solid content. it is preferable that the m ² or more. If the coating amount is too large, binder migration may occur when the upper ink receiving layer is coated on the undercoat layer, and the strength of the ink receiving layer may be reduced. Therefore, 30 g / m ² or less is preferable per side. . The coating amount of the undercoat layer is more preferably 6 to 25 g / m ² , still more preferably 7 to 20 g / m ² .

  EXAMPLES The present invention will next be described in more detail by way of examples, which should not be construed as limiting the invention thereto. Moreover, unless otherwise indicated, "part" and "%" in an example show a "mass part" and "mass%", respectively. In addition, the addition part number is a value of solid content conversion.

Example 1
(Formation of support)
To 100 parts of hardwood bleached kraft pulp (Canadian standard freeness 530 ml CSF) dispersed in water, 0.25 parts of cationized starch (Neotac 30T: manufactured by Japan Food Processing Co., Ltd.) and 0.20 parts of acid rosin sizing agent A stock was obtained by blending 0.5 parts of a liquid sulfuric acid band and talc (talc NTL: manufactured by Nippon Talc Co., Ltd.) whose addition amount was adjusted to have an ash content of 6%. This stock was formed into a paper with a Fourdrinier paper machine to obtain a web. Thereafter, oxidized starch (MS # 3800: manufactured by Nippon Food Chemical Co., Ltd.) is applied as a size solution to both sides of the paper by a size press so that the dry coating amount is 2.0 g / m ² per one side, and a cylinder drier It was dry. Thereafter, smoothing treatment was carried out using a steel calender and high quality paper (acidic paper) with a basis weight of 100 g / m ² was produced and used as a support.

(Formation of ink receiving layer)
Next, 45 parts of kaolin (Contour 1500, made by Imerys Co., Ltd.) and 55 parts of light calcium carbonate (TP-121MS, made by Okutama Kogyo Co., Ltd.) were water-dispersed using a coreless disperser to prepare a pigment slurry. In this pigment slurry, 2 parts of phosphate esterified starch (MS 4600, manufactured by Nippon Food Processing Co., Ltd.) as a binder, 8 parts of styrene butadiene latex (PA 0372, Nippon A & L Co., Ltd.), bivalent water soluble metal salt (magnesium chloride) 5 Mass parts, 0.5 parts by mass of nonionic polyoxyethylene surfactant (Reocol TD-90D: manufactured by Lion Corporation), calcium stearate lubricant which is a water-insoluble higher fatty acid salt (DEF-963TF, Nisshin Chemical Research Laboratory) 1.5 parts by mass, and a coating liquid for an ink receiving layer having a solid content concentration of 50% by mass was obtained. Subsequently, this coating liquid for an ink receiving layer was coated and dried on both sides of the support obtained above using a blade coater so that the dry coating weight per one side was 8 g / m ² . Thereafter, calender processing (temperature 30 ° C., linear pressure 80 kg / cm) was performed to prepare an ink jet recording medium. At this time, the total content of the water-soluble metal salt relative to the total mass of the ink receiving layer is 4.3%, the total content of the surfactant is 0.43%, and the total content of the lubricant is 1 .3%.

(Example 2)
An ink jet recording medium was produced in the same manner as in Example 1 except that the amount of the water-soluble metal salt added was changed to 30 parts by mass. At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 21%, the total content of the surfactant is 0.35%, and the total content of the lubricant is 1.1 %Met.

(Example 3)
A medium for inkjet recording was produced in the same manner as in Example 1 except that the amount of the water-soluble metal salt added was changed to 0.5 parts by mass. At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 0.44%, the total content of the surfactant is 0.44%, and the total content of the lubricant is 1 .3%.

(Example 4)
A medium for inkjet recording was produced in the same manner as in Example 1 except that the addition amount of the surfactant was changed to 0.1 parts by mass. At this time, the total content of the water-soluble metal salt relative to the total mass of the ink receiving layer is 4.3%, the total content of the surfactant is 0.086%, and the total content of the lubricant is 1 .3%.

(Example 5)
A medium for inkjet recording was produced in the same manner as in Example 1 except that the addition amount of the surfactant was changed to 5 parts by mass in Example 1. At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 4.1%, the total content of the surfactant is 4.1%, and the total content of the lubricant is 1 .2%.

(Example 6)
An inkjet recording medium was produced in the same manner as in Example 1 except that the amount of the lubricant added was 10 parts by mass. At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 4.0%, the total content of the surfactant is 0.40%, and the total content of the lubricant is 8 It was .0%.

(Example 7)
A medium for inkjet recording was produced in the same manner as in Example 1 except that the additive amount of the lubricant was changed to 0.1 part by mass in Example 1. At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 4.3%, the total content of the surfactant is 0.43%, and the total content of the lubricant is 0. It was .087%.

(Example 8)
An ink jet recording medium was produced in the same manner as in Example 1 except that the water soluble metal salt was changed to magnesium sulfate which is a divalent water soluble metal salt. At this time, the total content of the water-soluble metal salt relative to the total mass of the ink receiving layer is 4.3%, the total content of the surfactant is 0.43%, and the total content of the lubricant is 1 .3%.

(Example 9)
An ink jet recording medium was produced in the same manner as in Example 1 except that the water soluble metal salt was changed to calcium chloride which is a divalent water soluble metal salt. At this time, the total content of the water-soluble metal salt relative to the total mass of the ink receiving layer is 4.3%, the total content of the surfactant is 0.43%, and the total content of the lubricant is 1 .3%.

(Example 10)
An ink jet recording medium was produced in the same manner as in Example 1 except that the water soluble metal salt was changed to aluminum chloride which is a trivalent water soluble metal salt. At this time, the total content of the water-soluble metal salt relative to the total mass of the ink receiving layer is 4.3%, the total content of the surfactant is 0.43%, and the total content of the lubricant is 1 .3%.

(Example 11)
A medium for inkjet recording was produced in the same manner as in Example 1 except that the surfactant was changed to a nonionic acetylene glycol surfactant (Orphin PD004, manufactured by Nisshin Chemical Industry Co., Ltd.). At this time, the total content of the water-soluble metal salt relative to the total mass of the ink receiving layer is 4.3%, the total content of the surfactant is 0.43%, and the total content of the lubricant is 1 .3%.

(Example 12)
A medium for inkjet recording was produced in the same manner as in Example 1 except that the surfactant was changed to a nonionic silicone surfactant (Paintadd 32, manufactured by Dow Corning Asia Ltd.). At this time, the total content of the water-soluble metal salt relative to the total mass of the ink receiving layer is 4.3%, the total content of the surfactant is 0.43%, and the total content of the lubricant is 1 .3%.

(Example 13)
A paper substrate was prepared in the same manner as in Example 1. Next, 100 parts of synthetic silica (Nipgel AY-601, average particle diameter 6.0 μm, pore volume 1.6 cm ³ / g, Tosoh Silica Corporation) as a pigment, polyvinyl alcohol (PVA 117: Kuraray Corporation) as a binder 5 parts and 35 parts of ethylene-vinyl acetate (Polysol EVA AD-6: manufactured by Showa Highpolymer Co., Ltd.), 10 parts of a cationic polyamidine compound (Himax SC-700M: manufactured by Hymo) as a cationic polymer, divalent 5 parts by mass of water-soluble metal salt (magnesium sulfate), 0.5 parts by mass of nonionic polyoxyethylene surfactant (Reocol TD-90D: manufactured by Lion Corporation), polyethylene lubricant (SN coat 289, manufactured by Sannopco Corporation) 1.5 parts by mass was blended to obtain a coating liquid for an ink receiving layer having a solid content concentration of 25% by mass. Subsequently, the coating liquid for the ink receiving layer was coated and dried on one side of the support with an air knife coater so as to have an absolute dry coating amount of 6 g / m ² to coat the ink receiving layer. Thereafter, calendering was performed to prepare an ink jet recording medium. At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 3.2%, the total content of the surfactant is 0.32%, and the total content of the lubricant is 0 It was .96%.

(Example 14)
A medium for inkjet recording was produced in the same manner as in Example 13 except that the water-soluble metal salt was changed to calcium chloride which is a divalent water-soluble metal salt. At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 3.2%, the total content of the surfactant is 0.32%, and the total content of the lubricant is 0 It was .96%.

(Example 15)
A medium for inkjet recording was produced in the same manner as in Example 13 except that the surfactant was changed to a nonionic acetylene glycol surfactant (Orfin PD 004, manufactured by Nisshin Chemical Industry Co., Ltd.). At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 3.2%, the total content of the surfactant is 0.32%, and the total content of the lubricant is 0 It was .96%.

(Example 16)
A medium for inkjet recording was produced in the same manner as in Example 13 except that the support was changed to a polyethylene film in Example 13. At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 3.2%, the total content of the surfactant is 0.32%, and the total content of the lubricant is 0 It was .96%.

(Comparative example 1)
An ink jet recording medium was produced in the same manner as in Example 1 except that the water-soluble metal salt of the coating liquid for ink receiving layer was not added. At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 0%, the total content of the surfactant is 0.45%, and the total content of the lubricant is 1.3 %Met.

(Comparative example 2)
An ink jet recording medium was prepared in the same manner as in Example 1 except that no lubricant was added to the coating liquid for the ink receiving layer in Example 1. At this time, the total content of the water-soluble metal salt to the total mass of the ink receiving layer is 4.3%, the total content of the surfactant is 0.43%, and the total content of the lubricant is 0. %Met.

(Comparative example 3)
An ink jet recording medium was produced in the same manner as in Example 1 except that the surfactant in the coating liquid for forming an ink receiving layer was not added. At this time, the total content of the water-soluble metal salt relative to the total mass of the ink receiving layer is 4.3%, the total content of the surfactant is 0%, and the total content of the lubricant is 1.3 %Met.

  The following test was implemented about the obtained inkjet recording medium, and the result was shown to Tables 1-3.

(1) Color development of dye ink:
ISO standard image (ISO / JIS-SCID high definition color digital standard image data, name of image: portrait, image identification number: N1) using dye ink ink jet printer (MFC-J4510N: manufactured by Brother Industries, Ltd.) , And printed on the obtained inkjet recording medium. The printed image was evaluated visually.
◎: The recorded image is very clear and the contrast is clear, and can be practically used. Pass.
○: The recorded image is clear and the contrast is clear, and it can be used practically. Pass.
Δ: The recorded image is somewhat unclear and the contrast is somewhat blurred, but it can be practically used. Pass.
X: The recorded image is extremely blurred, the contrast is significantly blurred, and it can not be used practically. failure.

(2) Color development of pigment ink:
For ISO standard images (ISO / JIS-SCID high definition color digital standard image data, image name: portrait, image identification number: N1), using a pigment ink-only inkjet printer (CM8060 Color MFP: manufactured by Hewlett Packard Co.) Printing was performed on the obtained inkjet recording medium. The printed image was evaluated visually.
◎: The recorded image is very clear and the contrast is clear, and can be practically used. Pass.
○: The recorded image is clear and the contrast is clear, and it can be used practically. Pass.
Δ: The recorded image is somewhat unclear and the contrast is somewhat blurred, but it can be practically used. Pass.
X: The recorded image is extremely blurred, the contrast is significantly blurred, and it can not be used practically. failure.

(3) White space feeling:
The white space on the ink receiving layer was visually confirmed and evaluated according to the following criteria.
◎: There are no foreign substances or stains, and the sheet is extremely excellent in feeling of white space, and can be put to practical use. Pass.
○: Foreign matter and dirt are slightly generated, but the feeling of white space is excellent and practical. Pass.
Δ: A defect due to foreign matter or dirt occurs, which is inferior to the feeling of white space and can not be put to practical use. failure.
X: A defect due to foreign matter or stains occurs remarkably, and the feeling of white space is remarkably deteriorated, and can not be put to practical use. failure.

  As is clear from Tables 1 to 3, the ink jet recording media obtained in Examples 1 to 16 were excellent in the coloring properties of the dye ink and the pigment ink. Also, the feeling of white space was excellent.

  On the other hand, the ink jet recording medium obtained in Comparative Example 1 was inferior in color developability of the pigment ink because the ink receiving layer contained no water soluble metal salt. Further, the ink jet recording medium obtained in Comparative Example 2 did not contain a lubricant in the ink receiving layer, so that stains occurred during the calender process, resulting in poor white space feeling. Further, the ink jet recording medium obtained in Comparative Example 3 did not contain a surfactant in the ink receiving layer, so many foreign matters due to aggregates were mixed in the ink receiving layer, resulting in poor white space feeling. .

Claims (4)

An ink jet recording medium obtained by providing an ink receiving layer containing a pigment and a binder on at least one surface of a support and performing a calendering process, wherein the ink receiving layer is a lubricant, a surfactant and a water-soluble material. Contains metal salts and
It contains only nonionic surfactant as the surfactant,
The surfactant is a nonionic surfactant selected from an acetylene glycol surfactant, a perfluoroalkyl surfactant, a polyoxyethylene surfactant, or a silicone surfactant. Ink jet recording medium.
The inkjet recording medium according to claim 1, wherein the content of the surfactant is 0.01 to 3% by mass with respect to the dry mass of the ink receiving layer .   3. The ink jet recording medium according to claim 1, wherein the water soluble metal salt is a divalent or higher water soluble metal salt. The ink jet recording medium according to any one of claims 1 to 3, wherein the content of the lubricant is 0.005 to 1.3% by mass with respect to the dry mass of the ink receiving layer. .