JP2007100238A - Method for producing coated paper for printing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a coated paper for printing, providing good printed quality and feeling of the printed face, and having a low density. <P>SOLUTION: The coated paper for the printing is produced by coating the most inside coated layer neighboring a base paper by a spray coating method, and coating the most outside coated layer by a blade coating method in the method for producing the coated paper for the printing by coating a coating liquid containing a pigment and a binder on the base paper. The viscosity of the coating liquid used in the spray coating method is preferably within the range of 10-50 mPas at 1.0×10<SP>4</SP>(1/sec) shear rate for producing the coated paper more effectively. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a coated paper for printing, and relates to a method for producing a coated paper for printing having excellent production efficiency and excellent printing quality.

    In recent years, there has been an increasing demand for visually transmitting contents by using a large number of photographs and designs on printed materials and further colorizing them, and the demand for paper has also increased accordingly. In general, coated paper is roughly classified into high gloss coated paper and matte coated paper. High gloss coated paper is art paper, super art paper, coated paper or the like conventionally used for high-grade printing, and the printed finish is glossy with both high gloss and white paper gloss. Matte coated paper has a dull tone and matte tone depending on the glossiness of white paper and printing gloss. The matte tone is a flat and calm print with low gloss on both the white and printed sides, and the dull tone is an intermediate between glossy and matte tone, with low gloss on the white paper but high print gloss. is there. The matte tone is easier to read after printing than the conventional glossy tone, and demand is increasing in recent years. High gloss coated paper, dull coated paper, and matt coated paper have a difference in glossiness of blank paper before printing, but in any case, high glossiness after printing is an important issue. .

  Coated paper is produced by applying a coating solution consisting mainly of pigment and adhesive on the base paper by coating one or more layers, but it has a high-quality feeling after printing and is suitable for visual appeal. However, it is generally considered that it is preferable to provide two or more coating layers. When two or more coating layers are provided, the innermost coating layer that is first applied to the base paper has a sealing effect that suppresses penetration of the coating layer to be applied later into the base paper, The layer is applied for the purpose of improving the white paper appearance and print quality. On the other hand, there is a strong demand for weight reduction of printed matter from the viewpoints of resource saving and transportation cost, and attention must be paid to the reduction of coating amount. These two properties are contradictory, and it is considered very difficult to obtain a coated paper having both properties.

  As a method for coating the coating liquid on the base paper, a blade method, a roll transfer method, and a curtain coating method are generally used. With the blade coating method, the coating layer can be coated flat on the paper, and a coated paper having high smoothness and high white paper gloss can be obtained. However, it is a coating method in which the paint is pressed into the base paper when it passes through the blade, and it is a coating method that flattens the unevenness of the surface of the base paper, so that the fibers of the base paper are completely covered A large amount of coating is required. In particular, when the innermost coating layer that requires a sealing effect is applied, a coating more than necessary is applied, which is not preferable for reducing the weight of paper. The roll transfer method and curtain coating method can be applied with a small coating amount, and a coating layer can be obtained along the irregularities of the surface of the base paper, compared to the blade method. The amount of work can be kept low. However, these coating methods have problems such as the occurrence of mist during high-speed coating and the destabilization of the curtain film, and are sufficiently compatible with recent increases in the speed of paper machines and coating machines. I can't say that. Further, when the coating amount is small, it is difficult to sufficiently cover the base paper.

  In recent years, a spray coating method has been proposed as a new coating method in the field of paper pulp. The spray coating method is, for example, a method in which a coating paint is sprayed on the surface of paper from a single fluid nozzle called airless spray to coat the paper (see Non-Patent Document 1). In this method, no nip pressure is applied during coating, and no large shear stress is applied to the paper traveling direction during coating. Therefore, compared to the conventional blade coating method and roll transfer coating method, there is no gap. A coating layer with a large amount can be obtained. For this reason, the stiffness, whiteness, and opacity of the paper are increased, and the air permeability is decreased, so that improvement of blister resistance is expected. However, compared to the blade method and roll transfer method, the coated surface is formed along the unevenness of the surface of the base paper, so that the white paper glossiness is poor and the printed surface feeling after printing is also poor. As a method for producing paper, it is difficult to say that its utilization method has been sufficiently studied. One or more coating layers are provided only by the spray coating method, and a method for producing a coated paper for offset printing having high white paper glossiness and low air permeability is disclosed (see Patent Document 1). Even if only a high white paper glossiness is obtained by calendering or the like, the invention alone cannot improve the deterioration of the feeling after printing due to the unevenness of the base paper.

As described above, with the conventional method, it has been very difficult to achieve both low density of paper, that is, light weight, high operability, and good printing surface.
Paper pamphlet of technical cooperation Vol.56 No.4 P471-482 JP 2005-68614 A

  In view of such a situation, an object of the present invention is to provide a low-density coated coated paper having excellent print quality and operability.

As a result of intensive studies on the above problems, the inventors of the present invention are the innermost adjacent to the base paper in the method for manufacturing a coated paper for printing, in which a coating liquid containing a pigment and an adhesive is applied onto the base paper. After coating the coating layer with spray coating method, the outermost coating layer is coated with blade coating method, so that it has excellent operability, good printing surface feeling, and low density printing. It has been found that coated paper can be produced and obtained. In the present invention, the viscosity of the coating liquid used in the spray coating method for producing coated paper more effectively is 10 to 50 mPa · s at a shear rate of 1.0 × 10 ⁴ (1 / second). It is preferable that it is the range of these.

  According to the present invention, it is possible to obtain a coated paper for printing having excellent print quality and operability and low density. The spray coating is a coating method that forms a coating layer along the outline of a complete paper, unlike the conventional coating method. The base paper can be sufficiently coated with a small coating amount, and the effect of sealing is very high. By applying under coating by this spray coating and coating by blade coating that is superior to smoothness, coated paper having high smoothness, high gloss and good surface feeling after printing can be obtained. Can do.

In the present invention, in the method for producing a printing paper for coating two or more layers of a coating liquid containing a pigment and an adhesive on a base paper, the innermost coating layer adjacent to the base paper is spray-coated. It is important to provide the outermost coating layer by the blade coating method after being provided by the method. The spray coating is a coating method that forms a coating layer along the outline of a complete paper, unlike the conventional coating method. For this reason, it is possible to sufficiently cover the base paper with a small coating amount, and the sealing effect is very high. A preferable coating amount that exhibits the effect of the present invention is 0.5 to 6.0 g / m ² , more preferably 1.5 to 4.5 g / m ² per side. When the amount is less than 0.5 g / m ² , the covering of the base paper is not sufficient and the sealing effect is low, and even if a coating layer is provided thereon, the surface feeling of white paper or printed matter is inferior. When the amount is more than 6.0 g / m ² , the weight of the paper becomes heavy, which is not preferable because it is not suitable for reducing the weight of the paper which is one of the effects of the present invention. By applying undercoating by spray coating and coating with blade coating that is superior to smoothness on it, it is possible to obtain coated paper with high smoothness, high gloss and good surface feeling after printing it can. Moreover, since both the spray coating method and the blade coating method are excellent in high-speed coating suitability, coated paper can be produced very efficiently. The range of the coating speed is 1000 m / min or more, more preferably 1100 m / min or more. By coating at 1000 m / min or more, when the paper and the paint collide during spray coating, the pigment in the paint is easily oriented along the surface of the paper due to the high-speed movement of the paper, thereby improving the smoothness. .

  In the present invention, the spray coating method used for coating the innermost coating layer may be either on-machine or off-machine. Examples of spray nozzles include air spray and airless spray. Airless spray can pressurize the paint at high speed and spray fine paint due to shear stress caused by contact between the paint film and the atmosphere. It is preferable because grains can be formed and droplets can be spread on the paper surface in a good state, and contamination at the nozzle tip can be reduced. A preferable pressurizing condition when the paint is sprayed from the spray nozzle is 50 to 130 bar. The spray nozzles are preferably installed at intervals of 50 to 70 mm, and at that time, a preferable distance between the tip of the nozzle and the surface of the paper is 90 to 110 mm. Outside this range, uncoated portions tend to occur, and problems such as interference between adjacent nozzle paints tend to occur, making it difficult to obtain a good coated surface.

  Moreover, the conventionally used system can be used as the blade coating system used when forming the outermost coating layer. For example, there are roll transfer method and jet fountain method to supply coating liquid to paper, and jet fountain method also has validue dwell time that can change the scraping time with blade after the coating liquid contacts the paper There are two methods, the short dwell time method and the short time for scraping with a blade after the coating liquid contacts the paper. However, considering the recent increase in the speed of paper machines and coating machines, the validue time jet fountain system is preferred. Further, regarding the blade for scraping off the coating liquid, there are a vent blade and a bevel blade, but a bevel blade that gives a good white paper surface is preferable.

  As the coating pigment used in the coating liquid of the present invention, those conventionally used as coating pigments for paper can be used. The types of these pigments include inorganic calcium pigments such as heavy calcium carbonate, light calcium carbonate, clay, kaolin, talc, titanium dioxide, barium sulfate, calcium sulfate, zinc oxide, silicic acid, silicate, colloidal silica, and satin white. And organic pigments such as plastic pigments. Since the first coating layer used in spray coating only needs to obtain a sealing effect, it is preferable to mainly use calcium carbonate, more preferably heavy calcium carbonate, in order to improve whiteness and operability. It is. The blending amount is preferably 50 parts by weight or more, and most preferably 100 parts by weight per 100 parts by weight of the pigment.

  The adhesive used in the present invention is conventionally used for coated paper, such as styrene / butadiene, styrene / acrylic, ethylene / vinyl acetate, butadiene / methyl methacrylate, vinyl acetate / butyl acrylate, and the like. Synthetic adhesives such as various copolymers, polyvinyl alcohol, maleic anhydride copolymer, acrylic acid / methyl methacrylate copolymer, casein, soy protein, synthetic protein and other proteins, oxidized starch, cationized starch, One or more kinds of starches such as urea phosphate esterified starch and hydroxyethyl etherified starch, cellulose derivatives such as carboxymethyl cellulose, hydroxymethyl cellulose, and hydroxyethyl cellulose can be appropriately selected and used. These adhesives are preferably used in the range of 5 to 50 parts by weight, more preferably 10 to 40 parts by weight, based on 100 parts by weight of the pigment when used in a spray coating method. When the amount exceeds 50 parts by weight, the viscosity of the coating liquid becomes high, and disadvantages such as the problem of operability such as difficulty in passing through the piping and screen arise, which is not preferable. On the other hand, when the amount is less than 5 parts by weight, a sufficient surface strength cannot be obtained, which is not preferable. Moreover, when using for a blade coating system, it is preferable to use in the range of 5-35 weight part with respect to 100 weight part of pigments.

In the coating liquid of the present invention, various commonly used auxiliaries such as dispersants, thickeners, water retention agents, antifoaming agents, water resistance agents, dyes and fluorescent dyes can be used as auxiliaries.
The coating liquid used for spray coating of the present invention has a viscosity at a shear rate of 1.0 × 10 ⁴ (1 / second) of 10 to 50 mPa · s, more preferably 10 to 30 mPa · s, Improves the feeling of blank paper and printing, and also improves operability. Unlike the blade method, spray coating does not apply a high shearing force, but a moderate force is applied when paper air collides with the coating liquid. For this reason, the viscosity of the medium shear region as described in the present invention has an influence on the behavior of the paint after colliding with the paper, which is very important, the scattering property is good, and the paper and the coating liquid are in contact with each other. Viscosity at a shear rate of 1.0 × 10 ⁴ (1 / second) is important in order to control the ease of leveling. If it is lower than 10 mPa · s, the paint penetrates into the base paper before the paper and the coating liquid come into contact with each other and enters the drying zone. Is difficult to obtain and is not preferred. In addition, when it is higher than 50 mPa · s, the coating liquid does not spread sufficiently to the paper surface after colliding with the paper, and coating unevenness or the like is generated, which tends to be inferior to the blank paper feeling and the post printing feeling. It is not preferable.

  The base paper in the present invention comprises pulp, fillers and various auxiliaries. As the pulp, chemical pulp, semi-chemical pulp, mechanical pulp, waste paper pulp and the like can be used, and these can be properly used according to the purpose.

  The filler used for the base paper should be a known filler such as light calcium carbonate, heavy calcium carbonate, talc, kaolin, clay, silica, amorphous silicate, titanium oxide, synthetic resin filler, and light calcium carbonate-silica composite. However, it is preferable to blend an amorphous silicate and / or a light calcium carbonate-silica composite from the viewpoint of the balance between the weight reduction of the paper and the quality of the white paper and the printed surface. A compounding quantity is about 3 to 20 weight%. In the present invention, the amorphous silicate and / or the light calcium carbonate-silica composite is used to obtain a lower density and porous base paper. In the present invention, however, the spray coating is applied to the base paper of the paint. The penetration of the paint is suppressed, so that the penetration of the paint can be suppressed compared to the conventional coating method. For this reason, a surface feeling also becomes favorable and becomes lighter with the same thickness. These fillers may be used alone or in combination of two or more for the purpose of adjusting papermaking suitability and strength characteristics of the paper stock slurry.

  Further, in the present invention, by using a bulking agent (a low density agent) such as a surfactant which is an organic compound having an action of inhibiting the interfiber bonding of pulp, the white paper and the printing surface feel can be obtained at a low density. Good printing paper can be obtained, which is preferable. An organic compound having an action of inhibiting the interfiber bonding of pulp (hereinafter abbreviated as a binding inhibitor) is a compound having a hydrophobic group and a hydrophilic group, and has recently been put on the market for paper making to increase the bulk of paper. Further, the density reducing agent (or bulking agent) is suitable as the binding inhibitor of the present invention. For example, WO98 / 03730, JP-A-11-200284, JP-A-11-350380, JP-A-2003-2003 No. 96694, Japanese Patent Application Laid-Open No. 2003-96695, and the like. Specifically, higher alcohol ethylene and / or propylene oxide adduct, polyhydric alcohol type nonionic surfactant, higher fatty acid ethylene oxide adduct, polyhydric alcohol and fatty acid ester compound, polyhydric alcohol and fatty acid Ethylene oxide adducts of these ester compounds, fatty acid polyamidoamines, fatty acid diamidoamines, fatty acid monoamides, or polyalkylenepolyamine / fatty acid / epichlorohydrin condensates can be used alone or in combination of two or more. can do. Preferred are polyhydric alcohol and fatty acid ester compounds, fatty acid polyamidoamines, fatty acid diamidoamines, fatty acid monoamides, polyalkylene polyamine / fatty acid / epichlorohydrin condensates and the like. Bulky chemicals on the market include BASF's Sulsol VL, Bayer's Bi-Volume P Liquid, Kao's KB-08T, 08W, KB110, 115, Sanki's React Pake, Japan PMC ), PT-205, Nippon Oil & Fats Co., Ltd. DZ2220, DU3605, Arakawa Chemical Co., Ltd. R21001, and these may be used alone or in combination of two or more. In order to improve the air permeability of the base paper, the coated paper of the present invention preferably contains 0.1 to 10 parts by weight of pulp interfiber binding inhibitor per 100 parts by weight of pulp, in particular 0.2 to 1. It is preferable to contain 0.0 part by weight. The chemicals normally used in the paper making process, such as a paper strength enhancer, a sizing agent, an antifoaming agent, a colorant, a bulking agent, a softening agent, etc., as necessary for these stocks do not impair the effects of the present invention Paper can be added within the range.

The paper making method of the base paper is not particularly limited, and the base paper made by acid paper making, neutral paper making, and alkali paper making using a long net machine including a top wire, a round net machine, and a gap former machine. Any of these may be used. In addition, a base paper preliminarily coated with starch, polyvinyl alcohol or the like using a size press, a gate roll coater, a bill blade, or the like can be used. As the coating base paper, those having a basis weight of about 25 to 400 g / m ² used for general coated paper are used, and 30 to 180 g / m ² is used from the viewpoint of weight reduction and quality balance. It is preferably 35 to 80 g / m ² .

  In the present invention, the base paper is coated with a coating liquid containing a pigment and an adhesive by a spray coating method to provide the innermost coating layer adjacent to the base paper, and then the pigment and the adhesive By applying a coating solution containing s in the blade method and providing the outermost coating layer, a two-layer coating layer can be obtained. In the present invention, when three or more coating layers are provided, one or more intermediate coating layers may be provided between the coating layer adjacent to the base paper and the outermost coating layer. As the coating method, a blade coating method, a spray coating method, a curtain coating method, a film transfer coating method, etc. can be used, but it has excellent smoothness after coating and is of high quality. From the viewpoint of obtaining an intermediate coating layer, a blade coating method is preferred. Further, in the present invention, two layers are preferable from the viewpoint of the balance between the quality of the low-density, blank paper feeling and printing feeling.

The coating amount provided in the base paper, is not particularly limited, the total coating amount per one surface is about. 3 to 25 g / ^{m 2,} preferably 6~18g / ^{m 2.} The innermost coating layer adjacent to the base paper is preferably 0.5 to 6.0 g / m ² , more preferably 1.5 to 4.5 g / m ² , and the outermost coating layer is , preferably 5 to 15 g / ^{m 2,} more preferably from 6~11g / ^{m 2.}

  As a method for drying the wet coating layer, for example, usual methods such as a steam heater, a gas heater, an infrared heater, an electric heater, a hot air heater, a microwave, and a cylinder dryer are used.

  The coated paper coated and dried as described above can be subjected to a smoothing process without being subjected to a calendering process, or with a super calender, a high temperature soft nip calender, or the like.

EXAMPLES The present invention will be specifically described below with reference to examples, but of course not limited to these examples. In addition, unless otherwise indicated, the part and% in an example show a weight part and weight%, respectively. In addition, the test was done about the coating liquid and the obtained coated paper for offset printing based on the following evaluation methods.
(Evaluation methods)
(1) Paint viscosity: In the present invention, “Ultra High Shear Viscometer ACAV-A2” (ACA system, Finland) was used for viscosity measurement. A capillary unit for low shear rate measurement is attached to the measuring device, and the viscosity is measured at several points under a pressure condition (40 bar or less) that can be measured at a temperature of 30 ° C. From the resulting shear rate and viscosity curve, a shear rate of 1.0 × The viscosity at 10 ⁴ 1 / s was read.
(2) Density: Measured based on JIS P 8118.
(3) Blank paper glossiness: measured based on JIS P 8142.
(4) Glossiness of printing: Printed at a printing speed of 8000 sheets / minute using a flat-land printing ink (High Unity M manufactured by Toyo Ink) on a Roland flat-screen printing machine (4 colors) ( The surface of the four-color solid printing part) was measured based on JIS P 8142.
(5) Blank paper texture: The blank paper texture of the coated paper was visually evaluated.
◎: Extremely good, ◯: Good, △: Slightly inferior, ×: Inferior (6) Printed surface feeling: Ink for flat printing (High Unity M manufactured by Toyo Ink) on a Roland flat printing machine (4 colors) Using this, printing was performed at a printing speed of 8000 sheets / min, and the surface feeling of the obtained printed matter was visually evaluated.
A: Very good, B: Good, B: Slightly inferior, X: Inferior [Example 1]
(Coating fluid 1)
100 parts (solid content) of heavy calcium carbonate slurry (Fmatec FMT-90), 10 parts alkali thickening type styrene-butadiene copolymer latex (glass transition temperature -20 ° C, gel content 85%) 10 parts After adding 10 parts of hydroxyethyl etherified starch (PG295 manufactured by Penford), water was further added to obtain a coating solution 1 having a solid content concentration of 50%. At this time, the viscosity at a shear rate of 1.0 × 10 ⁴ (1 / second) is 16 mPa · s.
(Coating fluid 2)
Brazilian kaolin (manufactured by CADAM, Amazon Plus) as a pigment as 100 parts of pigment was blended with 0.1 part of sodium polyacrylate as a dispersant, and dispersed to prepare a kaolin slurry having a concentration of 70%. To 50 parts (solid content) of this kaolin slurry, 50 parts (solid content) of heavy calcium carbonate slurry (FMT-97, manufactured by PMMA Tech Co., Ltd.) was added, and styrene / butadiene copolymer latex (glass transition temperature -2 ° C.). , Gel content 85%) 12 parts, hydroxyethyl etherified starch (Penford PG295) 4 parts, fluorescent dye (Lancesse Brancopha UW Liquid), water further added to a solid content concentration of 64% A working liquid 2 was obtained.

The coated base paper used was a high quality paper having a basis weight of 45 g / m ² and a density of 0.75 g / cm ³ containing 7% of light calcium carbonate as a filler per weight of the base paper and 100% of chemical pulp as a papermaking pulp. .

An airless spray coater (coating condition: spray pressure condition: 50 bar) at a coating speed of 1500 m / min so that the coating amount of the above coating liquid 1 is 3 g / m ² on the above base paper. (Nozzle spacing: 60 mm, distance between nozzle and paper surface: 100 mm), and after drying, the above coating liquid 2 is 1500 m so that the coating amount per side is 7 g / m ^2. Double-side coating was performed using a jet fountain-type bevel blade coater at a coating speed of / min and dried so that the moisture content of the coated paper was 5%.

After drying, high-temperature soft nip calendering was performed under the conditions of a metal roll temperature of 150 ° C., an elastic roll Shore D hardness of 92, a paper feed speed of 1200 m / min, a linear pressure of 300 kg / cm, and a 4-nip to obtain a coated paper for offset printing. .
[Example 2]
10 parts of an alkali thickening type styrene-butadiene copolymer latex (glass transition temperature -20 ° C., gel content 85%) of coating liquid 1 of Example 1, hydroxyethyl etherified starch (PG295 manufactured by Penford) A coated paper for offset printing was obtained in the same manner as in Example 1, except that 30 parts of hydroxyethyl etherified starch (PG295 manufactured by Penford) was used instead of 10 parts and the coating concentration was 40%. . The viscosity at this time is 20 mPa · s.
[Example 3]
A coated paper for offset printing was obtained in the same manner as in Example 1 except that the filler for the base paper for coating in Example 1 was amorphous silicate.
[Example 4]
A coated paper for offset printing was obtained in the same manner as in Example 1 except that the filler of the base paper for coating of Example 1 was a light calcium carbonate-silica composite shown below.
<Method for producing light calcium carbonate-silica composite>
In a reaction vessel, 10 parts of commercially available Rosetta-type light calcium carbonate (trade name: Albuquer 5970 SMI Co., Ltd.) was dispersed in water, and the SiO ₂ concentration was 18.0 wt / wt% and the Na ₂ concentration was 6.1 wt / wt%. After adding 57 parts of sodium silicate solution, water was added to make the total amount 200 parts. This mixed slurry was heated with sufficient stirring with an agitator, and a 10% sulfuric acid solution was added to the slurry at 85 ° C. with stirring. The addition method is to keep the temperature constant, add sulfuric acid at a constant rate so that the final pH after addition of sulfuric acid is 8.0 and the total sulfuric acid addition time is 240 minutes, and add light calcium carbonate-silica composite A slurry. Obtained. At this time, the average particle diameter of the light calcium carbonate-silica composite A was 3.4 μm, and the weight ratio of the solid content of the light calcium carbonate and silica was 50/50.
[Example 5]
The base paper for coating of Example 1 contains 0.3% per base paper weight of polyhydric alcohol and fatty acid ester compound (KB-110 made by Kao), which is an organic compound having an action of inhibiting the interfiber binding of pulp. Except for the above, a coated paper for offset printing was obtained in the same manner as in Example 1. [Comparative Example 1]
In Example 1, a coated paper for offset printing was obtained in the same manner as in Example 1 except that the coating liquid 1 was changed to a roll transfer coater instead of a spray coater.
[Comparative Example 2]
In Example 1, a coating paper for offset printing was obtained in the same manner as in Example 1 except that the coating liquid concentration of the coating liquid 2 was changed to 45% and the spray coater was used instead of the blade coater. At this time, the viscosity at a shear rate of 1.0 × 10 ⁴ (1 / second) is 18 mPa · s.
[Comparative Example 3]
In Comparative Example 2, the coating material 1 was not applied, and the coating material 2 was applied with 9.0 g / m ² per side with a spray coater. A coated paper for offset printing was obtained in the same manner as in Comparative Example 2 except for the above.

  After drying, high-temperature soft nip calendering was performed under the conditions of a metal roll temperature of 150 ° C., an elastic roll Shore D hardness of 92, a paper passing speed of 1200 m / min, a linear pressure of 400 kg / cm, and a 4-nip to obtain a coated paper for offset printing. .

Claims (3)

In the manufacturing method of the coating paper for printing which coats two or more layers of coating liquid containing a pigment and an adhesive on the base paper, the innermost coating layer adjacent to the base paper is applied by a spray coating method. A method for producing a coated paper for printing, wherein the outermost coating layer is applied by a blade coating method. 2. The printing coating according to claim 1, wherein the viscosity of the coating liquid used in the spray coating method is in the range of 10 to 50 mPa · s at a shear rate of 1.0 × 10 ⁴ (1 / second). A method of manufacturing paper. Coating weight per side of the coating by spray coating method, a manufacturing method of the coated printing paper according to claim 1 or 2, characterized in that a 0.5 to 6.0 g / m ^2.