JP6490543B2 - Inkjet recording paper manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing ink jet recording paper.

  The ink jet recording system is a system in which ink droplets are ejected from fine nozzles onto a recording paper and adhered to form dots to perform recording. In recent years, due to technological advances such as ink jet printers, inks, and recording media, it has become easier to increase the recording speed, reduce the sound, or form images with high print quality, and are used in various fields. In particular, in fields such as commercial printing, digital information can be printed at high speed without making a plate, and it is possible to handle printing of various types of small lots or variable information. Recently, with the expansion of applications due to remarkable progress in high-speed and high-definition equipment, coated paper having the same texture as general printing coated paper (for example, offset printing paper) There is a growing demand for imparting inkjet suitability.

  However, when printing a general printing coated paper by the ink jet recording method, since the absorbability or drying property for the ink for ink jet is remarkably inferior, the image after printing is not sufficiently dried, and the printed image is rubbed. There is a problem of contamination.

  In the ink receiving layer of the conventional ink jet recording paper, the ink absorbing property is imparted by using a pigment mainly made of alumina, silica, boehmite or the like and having a large pore volume of the ink receiving layer, and after printing. By sufficiently drying the image, the problem of contamination caused by rubbing the printed image has been solved. However, these ink jet recording papers are inferior in texture to general printing coated papers. Also, pigments such as alumina, silica or boehmite are expensive and are not suitable for commercial printing fields such as on-demand printing. Further, when these pigments are used, the ink is absorbed before the printed dots are spread, the dots are not sufficiently filled, and white stripes are likely to occur in the printing direction.

  In conventional ink jet recording paper, inexpensive light calcium carbonate may be used to improve ink absorbability. A printing paper using light calcium carbonate having an oil absorption amount in a specific range is disclosed in an ink receiving layer of an inkjet recording paper (see, for example, Patent Document 1). Inkjet recording paper using light calcium carbonate as in Patent Document 1 has excellent ink absorbability, and has the same texture as a general printing coated paper, and is a pigment such as alumina, silica or boehmite. Is cheaper than

JP 2002-138391 A

  However, when light calcium carbonate is used as in Patent Document 1, dots may not spread sufficiently and white streaks may occur. This is particularly noticeable with high-speed inkjet printers.

  An object of the present invention is to provide a method for producing an ink jet recording paper having a texture similar to that of a general coated paper for printing and having excellent ink absorption and no white streaks when printing by an ink jet recording method. It is to be.

The method for producing an ink jet recording paper according to the present invention is a method for producing an ink jet recording paper obtained by providing an ink receiving layer containing a pigment and styrene budadiene latex on at least one side of a base paper and calendering it. The paint of the ink receiving layer contains a slightly cationic polymer having a cationization degree of more than 0 meq / g and not more than 3.0 meq / g, and heavy calcium carbonate is used as the pigment in the coating of the ink receiving layer. 1 to 45 parts by mass with respect to 100 parts by mass of the total pigment, and light calcium carbonate as the pigment is 1 to 40 parts by mass with respect to 100 parts by mass of the total pigment in the ink receiving layer. And the total content of heavy calcium carbonate and light calcium carbonate is 2 with respect to 100 parts by mass of the total pigment in the ink receiving layer. Or less 45 parts by mass or more parts, the ink-receiving layer is characterized by providing by coating the coating material for the ink-receiving layer in on-machine. The paint of the ink receiving layer contains 1 to 49 parts by weight of light calcium carbonate as a pigment with respect to 100 parts by weight of the total pigment in the ink receiving layer, and the total of heavy calcium carbonate and light calcium carbonate When the content is 2 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the total pigment in the paint of the ink receiving layer, the strength of the coating layer does not decrease and an appropriate offset printability is maintained, Ink absorbability can be further improved.

  In the method for producing an ink jet recording paper according to the present invention, the content of the slightly cationic polymer is 0.01 to 5.00 parts by mass with respect to 100 parts by mass of the total pigment in the paint of the ink receiving layer. It is preferable. It is possible to achieve both excellent ink absorbability and excellent coating layer strength.

  The present invention provides an ink jet recording paper having a texture similar to that of a general coated paper for printing and having excellent ink absorbability when the ink jet recording method is used for printing. Can be provided.

  Since the present invention can provide an inexpensive inkjet recording paper with the same production efficiency as that of a conventional general-purpose coated paper, the paper of the present invention is an inkjet used particularly in the field of commercial printing such as on-demand printing. Ideal for recording paper.

  That is, according to the present invention, it is possible to obtain an ink jet recording paper having a texture similar to that of a general printing coated paper, without impairing excellent ink absorbability, and having dots spread appropriately and no white streaking. Can do.

  Next, the present invention will be described in detail with reference to embodiments, but the present invention is not construed as being limited to these descriptions. As long as the effect of the present invention is exhibited, the embodiment may be variously modified.

  The ink jet recording paper manufacturing method according to the present embodiment is a method for manufacturing an ink jet recording paper obtained by calendering an ink receiving layer containing a pigment and styrene budadiene latex on at least one side of a base paper, The paint of the ink receiving layer contains a slightly cationic polymer having a degree of cationization of more than 0 meq / g and not more than 3.0 meq / g, and heavy calcium carbonate as a pigment is used as a total pigment in the paint of the ink receiving layer The ink receiving layer is provided by coating the ink receiving layer coating material on-machine with respect to 100 parts by weight.

<Base paper>
In the ink jet recording paper manufacturing method according to the present embodiment, the raw material pulp constituting the base paper is chemical pulp, LBKP (hardwood bleached kraft pulp), NBKP (softwood bleached kraft pulp), or the like; mechanical pulp, GP ( Groundwood pulp), PGW (pressure groundwood pulp), RMP (refinery mechanical pulp), TMP (thermomechanical pulp), CTMP (chemithermomechanical pulp), CMP (chemimechanical pulp) or CGP (chemiground pulp), etc .; wood Examples of the pulp include DIP (deinked pulp); and examples of the non-wood pulp include kenaf, bagasse, bamboo, and cotton. These can be used alone or in combination at any ratio. In addition, a synthetic fiber can be further blended within a range that does not impair the object and effect of the present invention. It is desirable to use chlorine-free pulp such as ECF (Elemental Chlorine Free) pulp or TCF (Totally Chlorine Free) pulp with low environmental impact.

  Moreover, it is preferable that the pulp constituting the base paper is a paper material having an appropriate beating degree as an inkjet recording paper. Suitable beating degree is, for example, Canadian standard freeness (freeness) (JIS P 8121: 1995 “Pulp Freeness Test Method”), 350 to 650 ml CSF. More preferably, it is 400-600CSF.

  Examples of the filler used for the base paper include heavy calcium carbonate, light calcium carbonate, magnesium carbonate, titanium dioxide, synthetic silica, alumina, talc, calcined kaolin clay, kaolin clay, bentonite, zeolite, aluminum hydroxide or zinc oxide. It is possible to use known fillers. The filler content in the paper is preferably 2 to 20 parts by mass with respect to 100 parts by mass of the dry mass of the pulp. More preferably, it is 4-15 mass parts. If it is less than 2 parts by mass, the opacity and whiteness may decrease, and the effect of adding a filler may not be obtained. When the amount exceeds 20 parts by mass, the strength of the paper is lowered, the load during printing or processing cannot be endured, and it may be difficult to use.

  In addition to the pulp and filler, the internal paper strength enhancer such as an internal sizing agent or wet paper strength enhancer, sulfuric acid band, yield improver, pitch control agent, coloring, etc. Various papermaking chemicals such as dyes, coloring pigments or fluorescent dyes can be used as appropriate. There are no particular limitations on the method for preparing each paper stock, the formulation, and the method for adding each papermaking chemical, as long as the effects of the present invention are not impaired.

  The paper making method of the base paper according to the present invention is not particularly limited, and a known paper machine such as a circular net paper machine, a long net paper machine, or a twin wire paper machine is applied using the above-mentioned stock. Paper making is possible.

  A surface sizing solution can be applied to the base paper obtained by the paper making method in order to suppress excessive penetration of the ink receiving layer coating solution into the base paper. The surface sizing liquid is not particularly limited, and examples thereof include known water-soluble polymers such as polyvinyl alcohol, polyacrylamide, and starch.

Although the basic weight of a base paper is not specifically limited, Usually, it is 30-300 g / m < ² >. More preferably 50 to 250 g / ^{m 2.}

<Ink receiving layer>
In the method for producing an ink jet recording paper according to the present invention, at least one ink receiving layer is provided on one side or both sides of the base paper obtained by the above method from the viewpoint of satisfying ink absorbability. The ink-receiving layer coating material (hereinafter sometimes referred to as ink-receiving layer coating material or ink-receiving layer coating solution) contains a pigment and styrene-butadiene latex as main components. In the present invention, the ink receiving layer coating material is applied on-machine. In general, as a method of applying the ink-receiving layer coating material to the base paper, the paper making and coating are performed in one step by directly connecting a paper machine for making the base paper and a coater for coating the coating material. There are an on-machine type that performs coating and an off-machine type that performs coating in a separate process from papermaking. In the present invention, the ink-receiving layer coating is applied to the base paper by an on-machine method, so that the ink dots are appropriately spread compared with the case of applying the off-machine method, and the printed image is printed. An ink receiving layer capable of suppressing the generation of white stripes can be obtained. This is because the ink-receiving layer provided by on-machine coating tends to be higher in density than the ink-receiving layer applied by off-machine coating, the ink absorption rate becomes slow, and the ink dots spread before spreading appropriately. It is presumed that the ink can be prevented from being absorbed into the receiving layer.

  In the present embodiment, the ink receiving layer coating material contains heavy calcium carbonate as a pigment. In addition to the heavy calcium carbonate, the ink receiving layer coating material may contain a known pigment used for general printing paper. Known pigments include, for example, kaolin, talc, light calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, titanium dioxide, zinc oxide, zinc sulfate, zinc carbonate, calcium silicate, aluminum silicate, magnesium silicate, diatomaceous earth, aluminum hydroxide Alternatively, an inorganic pigment such as magnesium hydroxide, or an organic pigment such as acrylic, styrene, ethylene, vinyl chloride, or nylon can be used. Among these, it is preferable to use at least one selected from light calcium carbonate, kaolin and talc together with heavy calcium carbonate because a texture similar to that of a general coated paper for printing can be obtained. In the present invention, it is preferable not to use expensive pigments such as alumina, silica or boehmite.

  The content of heavy calcium carbonate in the ink receiving layer is from 1 to 50 parts by weight, preferably from 5 to 45 parts by weight, based on 100 parts by weight of the total pigment in the ink receiving layer. More preferably, it is 10 parts by mass or more and 40 parts by mass or less. By containing 1 to 50 parts by weight of heavy calcium carbonate in the ink-receiving layer with respect to 100 parts by weight of the total pigment in the ink-receiving layer, the ink absorbability is improved and the dots are spread appropriately. An ink jet recording paper in which white stripes do not occur can be obtained. When the content of heavy calcium carbonate in the ink receiving layer exceeds 50 parts by mass, the dots spread too much and bleeding occurs. When the amount is less than 1 part by mass, the dots do not spread sufficiently and white streaks occur.

  In the ink jet recording paper manufacturing method according to the present embodiment, the ink receiving layer coating material contains light calcium carbonate as a pigment in an amount of 1 part by weight to 49 parts by weight with respect to 100 parts by weight of the total pigment in the ink receiving layer. In addition, the total content of heavy calcium carbonate and light calcium carbonate is preferably 2 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the total pigment in the ink-receiving layer coating material. In addition to heavy calcium carbonate as a pigment, the ink receiving layer is used in combination with 1 to 49 parts by weight of light calcium carbonate with respect to 100 parts by weight of the total pigment in the ink receiving layer. It can be improved. The content of light calcium carbonate in the ink receiving layer coating is more preferably 5 parts by mass or more and 35 parts by mass or less with respect to 100 parts by mass of the total pigment in the ink receiving layer. The total content of heavy calcium carbonate and light calcium carbonate is more preferably 20 parts by mass or more and 45 parts by mass or less with respect to 100 parts by mass of the total pigment in the ink receiving layer coating material. If the total content of heavy calcium carbonate and light calcium carbonate exceeds 50 parts by mass in the ink receiving layer, the coating layer strength decreases, and the offset printability may decrease. If the amount of the binder is increased in order to improve the coating layer strength, the absorbability decreases. Further, if the total content of heavy calcium carbonate and light calcium carbonate is less than 2 parts by mass in the ink receiving layer, dots may not spread sufficiently and white streaks may occur.

  As the binder used for the ink receiving layer, it is necessary to use styrene butadiene latex in order to make the coating layer strength the same as that of general printing paper. Since styrene butadiene latex is inexpensive, it is preferable from the viewpoint of production cost. Furthermore, depending on the purpose, for example, polyvinyl alcohol (including modified polyvinyl alcohol such as silanol-modified polyvinyl alcohol and carboxyl-modified polyvinyl alcohol), polyvinyl acetal, oxidized starch, etherified starch, carboxymethylcellulose, hydroxyethylcellulose, casein, gelatin, Soy protein, polyethyleneimide resin, polyvinylpyrrolidone resin, polyacrylic acid or its copolymer, maleic anhydride copolymer, acrylamide resin, acrylate resin, polyamide resin, polyurethane resin, polyester resin , Polyvinyl butyral resin, alkyd resin, epoxy resin, epichlorohydrin resin, urea resin, styrene-butadiene copolymer, methyl methacrylate General acrylic polymer latex such as tadiene copolymer, acrylic acid ester, methacrylic acid ester polymer or copolymer, or vinyl polymer latex such as ethylene-vinyl acetate copolymer A known binder used for printing paper can be used in combination. In particular, from the viewpoint of the coating layer strength of the ink-receiving layer and the production cost, it is preferable to use a styrene butadiene latex and starch that are used in general coated paper for printing.

  The total blending amount of the binder blended in the ink receiving layer coating material is determined in consideration of the printability of the recording medium, the strength of the ink receiving layer, and the coating liquid property. Usually, a binder (including styrene butadiene latex) may be added in a range of 3 to 60 parts by mass with respect to 100 parts by mass of the pigment. Preferably, it adds in the range of about 5-50 mass parts. If the amount is less than 3 parts by mass, the coating layer strength may decrease. If it exceeds 60 parts by mass, the ink absorbability may decrease. Of the total blending amount of the binder blended in the ink receiving layer coating material, the blending amount of the styrene butadiene latex is preferably 3 to 30 parts by mass with respect to 100 parts by mass of the pigment. If it is less than 3 parts by mass, the coating layer strength may decrease. If it exceeds 30 parts by mass, the ink absorbability may decrease.

  In the present invention, the ink-receiving layer coating material contains a slightly cationic polymer. In the present invention, the slightly cationic polymer refers to a polymer having a degree of cationization of more than 0 meq / g and 3.0 meq or less. The degree of cationization is more preferably 0.10 to 2.50 meq / g. The slightly cationic polymer has an effect of appropriately increasing the pore volume of the ink receiving layer and improving the ink absorbency while keeping the ink dot spread moderately. When the degree of cationization exceeds 3.0 meq / g, the strength of the ink receiving layer is inferior. Further, it tends to agglomerate with the heavy calcium carbonate contained in the ink-receiving layer coating material, and agglomerates are generated due to the increase in viscosity and stability of the coating material, so that there is a possibility that good coating suitability cannot be obtained. In addition, a cationic polymer which is a so-called fixing agent for inkjet ink has a high degree of cationization, and usually exceeds 3.0 meq / g, for example, 5.0 meq / g or more. It is distinguished from the slightly cationic polymer used in the present invention. Since the fixing agent for inkjet ink has a high degree of cationization, it aggregates with heavy calcium carbonate when added to the ink-receiving layer coating material. As a result, the paint aggregates and the fluidity is lowered, resulting in liquidity that is not suitable for on-machine coating which is high-speed coating (coating unevenness is likely to occur). The degree of cationization can be measured by a colloid titration method.

  The content of the slightly cationic polymer in the ink receiving layer coating is preferably 0.01 to 5.00 parts by weight, more preferably 100 parts by weight of the total pigment in the ink receiving layer coating. Is 0.10 to 3.00 parts by mass. If the amount is less than 0.01 parts by mass, the ink absorbability may be inferior. If it exceeds 5.00 parts by mass, the strength of the ink receiving layer may be inferior. In addition, agglomerates are generated due to the thickening of the paint or a decrease in stability, and there is a possibility that good coating suitability cannot be obtained.

  Examples of the slightly cationic polymer include polyethyleneimine, epichlorohydrin-modified polyalkylamine, polyamine, polyamine polyamide epichlorohydrin, dimethylamine ammonia epichlorohydrin, polyvinylbenzyltrimethylammonium halide, polydiacryldimethylammonium halide, polydimethylaminoethyl methacrylate hydrochloride, Polyvinylpyridium halide, cationic polyacrylamide, cationic polystyrene copolymer, diallyldimethylammonium chloride polymer, diallyldimethylammonium chloride sulfur dioxide copolymer, diallyldimethylammonium chloride amide copolymer, dicyandiamide formalin polycondensate, dicyandiamide Diethylenetriamine polycondensate, Reallylamine, polydiallylamine, polyallylamine hydrochloride, polyacrylamide resin, polyamide epoxy resin, melamine resin acid colloid, urea resin, cationic modified polyvinyl alcohol, amino acid type amphoteric surfactant, betaine type compound, polyamidine compound, modified polyamine Among the resins, modified polyamide resins, other quaternary ammonium salts, and cationic modified polyurethane resins, these are slightly cationic. These may be used alone or in combination of two or more.

  The slightly cationic polymer has a function of improving the ink absorbability of the ink receiving layer by increasing the pore volume of the ink receiving layer by an appropriate coagulation action with the styrene butadiene latex. That is, by including a slightly cationic polymer in the ink receiving layer, the pore volume of the coating layer is appropriately increased in the drying step of the ink receiving layer, and the ink absorbability is improved. By using a slightly cationic polymer, even when styrene butadiene latex is used as the binder, the ink receiving layer has excellent coating layer strength without excessive aggregation of the coating liquid for the ink receiving layer. It can be.

<Coating method>
As a method for applying the ink receiving layer coating material, a method using a coater directly connected to a paper machine for making a base paper may be used, and the type of the coater is not particularly limited. A known coater head such as a bar coater, comma coater, blade coater, curtain coater, gravure coater, short dwell coater or gate roll coater is used. The coating amount is not particularly limited, but is preferably 3 to 40 g / m ² per one side of the base paper in terms of solid content. More preferably 5 to 30 g / ^{m 2.} If it is less than 3 g / m ² , the ink absorbability may be inferior. If it exceeds 40 g / m ² , the cost increases, which is uneconomical. Further, one or more undercoat layers of the ink receiving layer can be formed before forming the ink receiving layer. As is obvious, the coating method of the undercoat layer is also an on-machine coating method.

  The drying method after coating is not particularly limited in the present invention, and examples include hot air drying, infrared drying, and drum drying.

  Furthermore, in the present invention, in order to obtain a texture similar to that of a general printing coated paper, an ink receiving layer is provided on the base paper, and then a calendar process is performed by a known calendar device such as a super calendar, a machine calendar, or a soft calendar. To give a suitable gloss.

  The ink receiving layer may be provided not only on one side of the base paper but also on both sides. It can be a duplex printing paper.

  Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. In the examples, “parts” and “%” represent “parts by mass” and “mass%”, respectively, unless otherwise specified. The number of added parts is a value in terms of solid content.

( Reference Example 1)
<Preparation of base paper>
Canadian standard freeness 410ml csf hardwood bleached kraft pulp 100 parts, light calcium carbonate (TP-121, Okutama Kogyo Co., Ltd.) 15 parts, cationized starch 0.3 parts and neutral rosin sizing agent (CC167, Seiko PMC) (Made) It added so that it might become 0.05 parts, and it was set as the paper stock. Using this stock, a base paper having a basis weight of 90 g / m ² was produced with a long mesh multi-cylinder paper machine. The produced base paper was coated with an oxidized starch aqueous solution by a gate roll coater so that the dry coating amount was 3.0 g / m ² on both sides.

<Preparation of coating solution for ink receiving layer>
Dispersant (Aron T-50, manufactured by Toagosei Co., Ltd.) in 55 parts of kaolin (Ultra White 90, manufactured by Engelhard) and 45 parts of heavy calcium carbonate (Carbital-97, manufactured by Imeris Minerals Japan) 0. One part was added, and after adding water, the mixture was dispersed in water with a Coreless disperser to obtain a pigment slurry. To this pigment slurry, 3 parts of phosphate esterified starch (MS4600, manufactured by Nippon Shokuhin Kako Co., Ltd.) and 13 parts of styrene bradiene latex (JSR0695, manufactured by JSR) as a binder, and polyacrylamide resin (product) as a slightly cationic polymer Name: 1.0 part of Flock Star ESC51, degree of cationization 1.2 meq / g, manufactured by Sanki Co., Ltd.) and 0.2 part of a fluorescent brightener (Kecoal BULC, manufactured by Nippon Soda Co., Ltd.) An ink receiving layer coating solution having a solid concentration of 45% was prepared.

<Preparation of inkjet recording paper>
The ink receiving layer coating liquid obtained above was applied on both sides of the base paper with a blade coater so that the dry coating amount per side was 15 g / m ^2, and after drying, calendering was performed. An inkjet recording paper having an amount of 120 g / m ² was produced.

(Example 2)
In Reference Example 1, the addition amount of heavy calcium carbonate (Carbital-97, manufactured by Imeris Minerals Japan) is 5 parts, and 40 parts of light calcium carbonate (Tama Pearl TP-121MS, manufactured by Okutama Kogyo Co., Ltd.) is blended. Except that, an ink jet recording paper was prepared in the same manner as in Reference Example 1.

(Example 3)
In Reference Example 1, the amount of heavy calcium carbonate (Carbital-97, manufactured by Imerizu Minerals Japan) is 10 parts, and further 35 parts of light calcium carbonate (Tama Pearl TP-121MS, manufactured by Okutama Kogyo Co., Ltd.) Except that, an ink jet recording paper was prepared in the same manner as in Reference Example 1.

Example 4
In Reference Example 1, the addition amount of heavy calcium carbonate (Carbital-97, manufactured by Imeris Minerals Japan) is 25 parts, and further 20 parts of light calcium carbonate (Tama Pearl TP-121MS, manufactured by Okutama Kogyo Co., Ltd.) is blended. Except that, an ink jet recording paper was prepared in the same manner as in Reference Example 1.

( Reference Example 5)
In Reference Example 1, instead of 1.0 part of polyacrylamide resin (product name: Flockster ESC51, cationization degree 1.2 meq / g, manufactured by Sanki Co., Ltd.) as a slightly cationic polymer in the ink receiving layer coating liquid In the same manner as in Reference Example 1 except that 0.05 part of a modified polyamide resin (product name: Sumirez Resin SPI-203 (50) H, cationization degree 3.0 meq / g, manufactured by Taoka Chemical Co., Ltd.) was added. On-demand inkjet printing paper was made.

( Reference Example 6)
In Reference Example 1, instead of 1.0 part of polyacrylamide resin (product name: Flockster ESC51, cationization degree 1.2 meq / g, manufactured by Sanki Co., Ltd.) as a slightly cationic polymer in the ink receiving layer coating liquid On-demand inkjet printing paper was prepared in the same manner as in Reference Example 1 except that 3.0 parts of a modified polyamine resin (product name: PA629, cationization degree 0.05 meq / g, manufactured by Seiko PMC) was added. .

(Example 7)
In Reference Example 1, 40 parts of heavy calcium carbonate (Carbital-97, manufactured by Imeris Minerals Japan) was added, and 5 parts of light calcium carbonate (Tama Pearl TP-121MS, manufactured by Okutama Kogyo Co., Ltd.) was added. In the same manner as in Reference Example 1, an inkjet recording paper was prepared.

(Example 8)
In Reference Example 1, 80 parts of kaolin (Ultra White 90, manufactured by Engelhard) are added, 10 parts of heavy calcium carbonate (Carbital-97, manufactured by Imeris Minerals Japan) are added, and light calcium carbonate is further added. Inkjet recording paper was prepared in the same manner as in Reference Example 1 except that 10 parts of Tamapearl TP-121MS (Okutama Kogyo Co., Ltd.) were blended.

( Reference Example 9)
Reference Example 1, kaolin (Ultra White 90, Engelhard Corp.) was added 99 parts of heavy calcium carbonate (Carbital-97, manufactured by Imerys Minerals Japan KK) except for adding 1 part of a reference example In the same manner as in Example 1, an ink jet recording paper was prepared.

(Example 10)
In Reference Example 1, 98 parts of kaolin (Ultra White 90, manufactured by Engelhard) was added, 1 part of heavy calcium carbonate (Carbital-97, manufactured by Imeris Minerals Japan) was added, and light calcium carbonate was further added. Inkjet recording paper was prepared in the same manner as in Reference Example 1 except that 1 part of Tamapearl TP-121MS (Okutama Kogyo Co., Ltd.) was blended.

( Reference Example 11)
In Reference Example 1, 50 parts of kaolin (Ultra White 90, manufactured by Engelhard) are added, 40 parts of heavy calcium carbonate (Carbital-97, manufactured by Imeris Minerals Japan) are added, and light calcium carbonate is added. Inkjet recording paper was prepared in the same manner as in Reference Example 1 except that 10 parts of Tamapearl TP-121MS (Okutama Kogyo Co., Ltd.) were blended.

( Reference Example 12)
Reference Example 1, polyacrylamide resins as a fine cationic polymer (Product name: Flock Star ESC51, degree of cationization 1.2 meq / g, Sansho Co., Ltd.) except for adding 5.0 parts of the Example 1 Inkjet recording paper was prepared in the same manner as described above.

(Comparative Example 1)
In Reference Example 1, instead of 45 parts of heavy calcium carbonate (Carbital-97, Imeris Minerals Japan) 45 parts of light calcium carbonate (Tama Pearl TP-121MS, manufactured by Okutama Kogyo Co., Ltd.) was added. Then, an ink jet recording paper was prepared in the same manner as in Reference Example 1.

(Comparative Example 2)
In Reference Example 1, the addition amount of kaolin (Ultra White 90, manufactured by Engelhard) was 45 parts, and the addition amount of heavy calcium carbonate (Carbital-97, manufactured by Imeris Minerals Japan) was 55 parts. In the same manner as in Reference Example 1, an inkjet recording paper was prepared.

(Comparative Example 3)
In Reference Example 1, kaolin (Ultra White 90, manufactured by Engelhard) was not added, and the amount of heavy calcium carbonate (Carbital-97, manufactured by Imeris Minerals Japan) was 100 parts, Inkjet recording paper was prepared in the same manner as in Reference Example 1.

(Comparative Example 4)
Reference Example 1, except that no addition of fine cationic polymer, to prepare an ink jet recording paper in the same manner as in Reference Example 1.

(Comparative Example 5)
The same base paper as in Reference Example 1 was produced and wound up once. Next, the same coating liquid as in Reference Example 1 was applied to both sides of this base paper with a blade coater so that the dry coating amount per side was 15 g / m ^2. An inkjet recording paper of / m ² was produced. (So-called off-machine coating was performed.)

(Comparative Example 6)
Reference Example 1, without addition of styrene bra diene latex (JSR0695, JSR Corp.), phosphoric acid esterified starch except for using (MS4600, manufactured by Nihon Shokuhin Kako Co., Ltd.) 16 parts, in the same manner as in Reference Example 1 inkjet Recording paper was prepared.

(Comparative Example 7)
In Reference Example 1, a cationic polyamidine resin (trade name: Himax SC-700L, cationization degree 4.5 meq / g, manufactured by Hymo Co., Ltd.), which is a fixing agent for inkjet inks, instead of a slightly cationic polymer 0 An inkjet printing paper was prepared in the same manner as in Reference Example 1 except that .05 parts was added.

  Tables 1 and 2 show the configurations and evaluation results of the ink jet recording paper obtained in each example and comparative example. The evaluation in the table was carried out by the following method.

(1) Evaluation of ink absorbency Using the following inkjet printer, solid printing was performed, and after 10 seconds of printing, white paper was piled up and rubbed by hand from above, and the ink set-off was visually evaluated.
Printer A: TruePressJet520 (Dainippon Screen Mfg. Co., Ltd.)
(Double-circle): There is no set-off and it can be used practically.
○: Slight set-off occurs but can be used practically.
Δ: Set-off occurred and impractical.
X: The set-off occurs remarkably and is not practical.
“◯” and “◎” are excellent in terms of ink fixing properties.
(2) Evaluation of white streaks Solid printing was performed using the following inkjet printer, and white streaks were visually evaluated.
Printer A: TruePressJet520 (Dainippon Screen Mfg. Co., Ltd.)
(Double-circle): There is no white stripe at all and it can be used practically.
○: Slight white streaks occur, but can be used practically.
Δ: White streaks appear, impractical.
X: White streaks are remarkably generated and impractical.
“○” and “◎” are excellent in terms of white lines.
(3) Evaluation of bleeding Printing was performed using the following inkjet printer, and the bleeding of the ink was visually evaluated.
Printer A: TruePressJet520 (Dainippon Screen Mfg. Co., Ltd.)
(Double-circle): There is no blur and it can be used practically.
○: Slight blurring occurs but can be practically used.
Δ: Smudge occurs and is not practical.
X: Smudge occurs significantly and is not practical.
“◯” and “◎” are excellent in terms of ink bleeding.
(4) Evaluation of coating layer strength Printing was performed using an RI tester (manufactured by Meisei Seisakusho), and the coating layer strength was visually evaluated.
(Double-circle): The coating layer strength is strong and can be used practically.
○: The coating layer strength is slightly reduced, but can be used practically.
(Triangle | delta): The coating layer intensity | strength falls and it is unpractical.
X: The coating layer strength is remarkably lowered and is not practical.
“◯” and “◎” are excellent in terms of coating layer strength.

  As is apparent from Table 1, the ink jet recording papers obtained in Examples 1 to 12 are excellent in ink absorbability and bleeding of the ink jet printer, and have a practical level of suitability for white streaks.

  The ink jet recording paper obtained in Comparative Example 1 did not contain heavy calcium carbonate in the ink receiving layer, and therefore was not suitable for white streaks. The ink jet recording paper obtained in Comparative Examples 2 and 3 contained a large amount of heavy calcium carbonate in the ink receiving layer, so that the ink spread too much and bleeding occurred. In Comparative Example 4, since the fine cationic polymer was not added to the ink receiving layer coating material, the bleeding and ink absorbability were inferior. Comparative Example 5 was not suitable for white streak because the ink-receiving layer coating was not applied by on-machine coating. Since Comparative Example 6 did not contain styrene bradiene latex in the ink receiving layer, the coating layer strength was inferior. In Comparative Example 7, the ink receiving layer contained a cationic polymer having a degree of cationization exceeding 3.0 meq / g, so that the coating layer strength was inferior.

Claims (2)

An ink receiving layer comprising a pigment and styrene budadiene latex is provided on at least one side of a base paper, and a method for producing an ink jet recording paper obtained by calendering,
The ink-receiving layer paint contains a slightly cationic polymer having a cationization degree of more than 0 meq / g and not more than 3.0 meq / g, and heavy calcium carbonate is used as the pigment in the ink-receiving layer paint. 1 to 45 parts by mass with respect to 100 parts by mass of the total pigment, and light calcium carbonate as the pigment is 1 to 40 parts by mass with respect to 100 parts by mass of the total pigment in the ink receiving layer. And the total content of heavy calcium carbonate and light calcium carbonate is 2 to 45 parts by mass with respect to 100 parts by mass of the total pigment in the ink receiving layer,
The method for producing an ink jet recording paper, wherein the ink receiving layer is provided by applying the ink receiving layer coating material on-machine. Inkjet according to claim 1, wherein the content of fine cationic polymer, characterized in that said ink-receiving layer from 0.01 to 5.00 parts by weight of the total pigment 100 parts by weight in the paint Printing paper manufacturing method.