JP5341798B2 - Coated paper for printing - Google Patents

Description

  The present invention relates to a coated paper for printing having a texture with a texture. More specifically, the present invention relates to a coated paper for printing having a texture with a feeling of unevenness, which has no gloss unevenness on the printing surface and is excellent in printability.

  In the coated paper for printing, the aesthetic appearance when printed is an important element as a product. There are various factors of this aesthetic appearance. One of them is the uniform glossiness of the printed surface. If the unevenness of the base paper, the coating unevenness due to the coating layer, the non-uniformity of the internal structure of the coating layer, and the subtle irregular irregularities on the surface of the coating layer are significant, the ink adheres to each location on the paper surface. The quantity distribution changes, resulting in printed matter with a lot of gloss unevenness. As a means for improving this, in the case of mat coated paper in which the overall glossiness is reduced, the gloss unevenness tends to be reduced, but the gloss unevenness does not disappear completely.

  The textured printing coated paper provided by imparting a concavo-convex shape to the surface of the coated paper for printing has the advantage of increasing the aesthetics as the coated paper for printing. As a conventional technique, there is a coated paper for printing having a texture with a feeling of unevenness in which unevenness due to the structure of the coating layer is expressed using an organic pigment in the coating layer. This technique has an advantage that the texture of the unevenness can be controlled by adjusting the blending amount of the organic pigment. However, when the amount of the organic pigment is too large, troubles such as paper blocking occur, and as a result, the aesthetic appearance of the coated paper for printing is impaired. Therefore, there is a method using an organic pigment whose glass transition temperature is controlled (see, for example, Patent Document 1), but it is not sufficiently effective, and it is also caused by troubles such as paper blocking, and the aesthetics are impaired. The problem is that it is not completely eliminated and the printability is poor.

  A method is also known in which a base paper is processed into a concavo-convex shape and a coating layer is provided thereon (see, for example, Patent Document 2). However, the coating layer is provided uniformly on a concavo-convex base paper. It is very difficult, and as a result, the coated paper for printing has unevenness in the thickness of the coating layer, and as a result, uneven glossiness of the printed surface occurs.

  That is, the present situation is that a coated paper for printing having a texture with no unevenness in gloss on the printing surface and excellent printability has not yet been found.

JP 2008-208474 A Japanese Patent No. 2889120

  An object of the present invention is to provide a coated paper for printing having a texture with a feeling of unevenness that has no gloss unevenness on the printing surface and is excellent in printability.

As a result of intensive studies to solve the above problems, the present inventors have invented the following coated paper for printing. That is, in the coated paper for printing in which at least one layer is provided on the base paper and a coating layer mainly composed of a pigment and an adhesive is provided, the outermost layer has a solid content mass of 2.0 g / m ² or more to 20.0 g / m2 per side. provided in a coating amount of m ² or less in the range, then the outermost layer, the arithmetic average roughness defined by JIS B 0601-2001 (Ra) 3.6μm or 8.0μm or less, is defined by the following It is a coated paper for printing characterized by performing uneven | corrugated processing so that a recessed part space | interval may be set to 120-600 micrometers.
The distance between the recesses is the horizontal distance between the point recognized as the deepest part of the recess and the point at the deepest part of the recess closest to that point in the contour curve between two points at an arbitrary 1.0 mm interval. The average of the values obtained by performing this measurement 32 times is used. Note that the recess is a region with a height difference of 12 μm or more within a distance of 200 μm in the horizontal direction from the point that can be recognized as the minimum height point in the contour curve between the two points of 1.0 mm above. In this case, an area centered on the deepest part is shown.

Furthermore, the outermost layer is provided with a coating weight in the range of 4.0 g / m ² or more and 10.0 g / m ² or less of solid content per side by any one of an air knife coater, a film transfer coater, a curtain coater, and a spray coater. It is preferred that Further, it is preferable that at least one layer or more is provided between the outermost layer and the base paper and an undercoat layer having a coating amount of 5.0 g / m ² or more of solid content per side by a blade coater.

  The coated paper for printing according to the present invention is characterized in that it is a printing paper having a texture with an uneven feeling that has no gloss unevenness on the printing surface and is excellent in printability.

  Hereinafter, the coated paper for printing of the present invention will be described in detail. The coated paper for printing according to the present invention is a paper having at least one layer on the base paper and a coating layer mainly composed of a pigment and an adhesive. The outermost layer in the present invention is the farthest from the base paper. This is a positioned layer. When there is only one coating layer provided on the base paper, the coating layer is the outermost layer. The undercoat layer in the present invention is provided as a coating layer other than the above outermost layer, and when there is only one coating layer provided on the base paper, it means that there is no undercoat layer. .

The coated paper for printing of the present invention is characterized in that a coating layer having a coating amount of 2.0 g / m ² or more and 20.0 g / m ² or less of solid content per side is provided as the outermost layer. When the outermost layer coating amount is less than 2.0 g / m ² of solid content per side, the outermost layer cannot sufficiently cover the base paper or the layer immediately below the outermost layer. Unevenness occurs. In addition, when the coating amount on the outermost layer exceeds the solid content mass of 20.0 g / m ² , it is generally difficult to operate within the optimum operating range in each coating method, and the printability is impaired due to disturbance of the coating surface. It is.

  The coated paper for printing according to the present invention is characterized in that the outermost surface layer is subjected to unevenness processing so that the arithmetic average roughness (Ra) specified in JIS B 0601-2001 is 3.6 μm or more and 8.0 μm or less. To do. When the arithmetic average roughness (Ra) is less than 3.6 μm, the texture with a feeling of unevenness is impaired. When the arithmetic average roughness (Ra) exceeds 8.0 μm, a portion where the ink does not adhere is generated, and the original function as the coated paper for printing is impaired. As a result of intensive studies, the present inventor has found that it is optimal that the outermost layer has an arithmetic average roughness (Ra) defined in JIS B 0601-2001 of 3.6 μm or more and 8.0 μm or less. .

  The coated paper for printing according to the present invention is characterized in that the outermost surface layer is subjected to uneven processing so that the interval between the recesses is 120 to 600 μm. The distance between the recesses is determined by observing the printing coated paper at a magnification of 200 times using a color 3D laser microscope VK-8700 manufactured by KEYENCE, and in the contour curve between two points at an arbitrary 1.0 mm interval, The distance in the horizontal direction between the point recognized as the point and the point at the deepest part of the recess closest to the point was measured, and this value was taken as the average value of 32 measurements. Note that the recess is a region with a height difference of 12 μm or more within a distance of 200 μm in the horizontal direction from the point that can be recognized as the minimum height point in the contour curve between the two points of 1.0 mm above. In this case, an area centered on the deepest part is shown. When the interval between the concave portions is less than 120 μm, the interval between the concaves and convexes is too narrow, so that the texture with a feeling of irregularities is lost due to approaching the conventional coated paper for printing with high smoothness. When the interval between the recesses exceeds 600 μm, the area where the recess does not exist is too large, and the printing unevenness in the area can be visually recognized. As a result of intensive studies, the present inventor has found that the unevenness interval of the outermost layer is optimally 120 to 600 μm.

In the coated paper for printing of the present invention, the method for providing the outermost layer is not limited at all. Examples thereof include a blade coater, a rod coater, a curtain coater, an air knife coater, a spray coater, and various film transfer coaters such as a size press, a gate roll, and a shim sizer. Further, the outermost layer should be provided with a coating weight in a range of 4.0 g / m ² or more and 10.0 g / m ² or less of solid content per side by any one of an air knife coater, a film transfer coater, a curtain coater, and a spray coater. Is more preferable. In the case of any one of an air knife coater, a film transfer coater, a curtain coater, and a spray coater, it is preferable that the coating is in a contour coating or a coating state close thereto, the thickness unevenness of the coating layer is small, and the gloss unevenness of the printing surface is also reduced. . However, when using an air knife coater, film transfer coater, curtain coater, or spray coater, the coating solution concentration is generally lower than when using a blade coater or rod coater for controlling the coating amount. When using an air knife coater, a film transfer coater, a curtain coater, or a spray coater, the coating amount is more than 4.0 g / m ² on one side of the base paper or the layer immediately below the outermost layer. A coating is sufficient and more preferred. Moreover, when using an air knife coater, a film transfer coater, a curtain coater, or a spray coater, the coating amount is less than 10.0 g / m ² on one side, and coating is possible under optimum operating conditions. A more preferable uniform coating layer is formed. Of course, even when an air knife coater, a film transfer coater, a curtain coater, or a spray coater is used, the coating amount of the outermost layer is in a range of a solid content mass of 2.0 g / m ² or more and 20.0 g / m ² or less per side. If so, the effects of the present invention are sufficiently exhibited.

The present invention is characterized in that it is a coated paper for printing having at least one layer on a base paper and a coating layer mainly composed of a pigment and an adhesive, and there is no limitation on the number of coating layers on the base paper. Is not to be done. More preferably, an undercoat layer having a coating amount of at least one layer and a solid content of 5.0 g / m ² or more per side is provided by a blade coater between the outermost layer and the base paper. The presence of an undercoat layer provided by a blade coater having a coating solid content mass of 5.0 g / m ² or more is more preferable because a smoother surface is formed and thickness unevenness of the outermost layer is eliminated.

  The present invention is characterized in that after the outermost layer is provided, the outermost layer is subjected to uneven processing. Even if the outermost layer is provided before the outermost layer is provided, for example, after the surface of the undercoat layer or the base paper is subjected to unevenness processing, the effect of the present invention is not exhibited unless the outermost surface layer is subjected to unevenness processing. By applying unevenness to the surface of the outermost layer, there is provided a coated paper for printing having excellent printability while having a glossy unevenness on the printing surface and having a texture with an uneven feeling. The surface roughness of the base paper or the undercoat layer in the present invention is not limited at all, and various surface treatments and calendar treatments may be performed as necessary. When performing calendar finishing treatment, a device composed of a combination of hard rolls, elastic rolls, a pair of hard rolls and elastic rolls is preferably used as a machine calendar, soft nip calendar, super calendar, multi-stage calendar, It is called a nip calender or the like and may be heated intentionally. The temperature of the roll during overheating may reach a high temperature of about 40 ° C to a high temperature of about 250 ° C. Also, an apparatus composed of a combination of a belt and a roll can be used, which is called a shoe calender, a metal belt calender, or the like.

  In the present invention, there is no limitation on the method of applying the uneven process to the outermost layer. A paper passing process using a processed embossing roll is generally used, but any method such as using a felt surface having a concavo-convex shape at regular intervals can be employed. For embossing rolls, direct engraving and sand blasting methods, acid corrugation, unevenness by means of acid corrosion, meal engraving created by pressing the original roll and transferring the shape to another roll, etc. Any method may be used. However, if the outermost surface after processing is arithmetic mean roughness (Ra) 3.6 μm or more and 8.0 μm or less as defined in JIS B 0601-2001, and the recess interval is not 120 to 600 μm, the effect of the present invention is Not expressed.

  The present invention is characterized in that it is a coated paper for printing having at least one layer on a base paper and a coating layer mainly composed of a pigment and an adhesive, and the pigment used is not limited at all. Absent. For example, heavy calcium carbonate, various light calcium carbonates, kaolin clay, mica, talc, plate barium sulfate, plate magnesium hydroxide, satin white, lithopone, titanium dioxide, alumina, aluminum hydroxide, zinc oxide, magnesium carbonate, natural Examples thereof include silica, dry synthetic silica, wet synthetic silica, organic pigments, modified ones thereof, or a composite of two or more of these. These can be used alone or in combination.

  The present invention is a coated paper for printing having at least one layer on a base paper and a coating layer mainly composed of a pigment and an adhesive, and the adhesive used is not limited at all. is not. For example, various copolymer latexes such as styrene-butadiene latex, acrylic, polyvinyl acetate, ethylene-vinyl acetate, formalin such as polyvinyl alcohol, modified polyvinyl alcohol, sodium polyacrylate, polyethylene oxide, polyacrylamide, urea or melamine Water-soluble synthetic compounds such as resin, polyethyleneimine, polyamide polyamine, epichlorohydrin and the like can be mentioned. Furthermore, starch purified from natural plants, hydroxyethylated starch, oxidized starch, etherified starch, phosphate esterified starch, enzyme-modified starch, cold water soluble starch obtained by flash drying them, dextrin, mannan, chitosan, arabi Examples thereof include natural polysaccharides such as nogalactan, glycogen, inulin, pectin, hyaluronic acid, carboxymethylcellulose, and hydroxyethylcellulose, oligomers thereof, and modified products thereof. Examples thereof include natural proteins such as casein, gelatin, soybean protein, collagen, and modified products thereof, and synthetic polymers and oligomers such as polylactic acid and peptides. These can be used alone or in combination. Further, the adhesive can be used after cation modification.

  The coating liquid for providing the coating layer of the present invention includes a thickener, a dispersant, an antifoaming agent, a surfactant, a pH adjuster, and water resistance as required in addition to the pigment and adhesive. Various commonly used auxiliaries such as a colorant and a coloring agent can be contained.

  The base paper used in the present invention includes chemical pulps such as LBKP and NBKP, mechanical pulps such as GP, PGWRMP, TMP, CTMP, and CGP, and various wood pulps such as waste paper pulp, cotton, hemp, bamboo, sugarcane, corn Plant fibers such as kenaf, animal fibers such as wool and silk, cellulose regenerated fibers such as rayon, cupra and lyocell, semi-synthetic fibers such as acetate, polyamide fibers, polyester fibers, polyacrylonitrile fibers, polyvinyl alcohol fibers Further, chemical fibers such as polypropylene fibers, polyvinylidene chloride fibers, and polyurethane fibers, and inorganic fibers such as glass fibers, metal fibers, and carbon fibers in a sheet form are used. These fibers include heavy calcium carbonate, light calcium carbonate, kaolin, talc, clay, titanium dioxide, aluminum hydroxide, silica, alumina, organic pigments, various fillers, adhesives, sizing agents, fixing agents, and retention agents. Various compounding agents such as a paper strength enhancer can be suitably contained in accordance with each step and each material.

  When manufacturing the base paper, a softening agent can be suitably contained in order to develop the effect of uneven processing. The softening agent here is a compound having a hydrophobic group and a hydrophilic group, and is an oil-based nonionic surfactant, a sugar alcohol-based nonionic surfactant, a sugar-based nonionic surfactant, a polyhydric alcohol. Nonionic surfactants, higher alcohols, higher alcohol ethylene and / or propylene oxide adducts, higher fatty acid ethylene oxide adducts, polyhydric alcohol and fatty acid ester compounds, fatty acid polyamidoamines, and the like can be used.

  As a method for producing the base paper, a general paper making process using a paper machine known in the paper industry such as a long paper machine, a twin wire paper machine, a combination paper machine, a circular paper machine, a Yankee paper machine, a wet method, One or more are appropriately selected from each step such as dry method, chemical bond, thermal bond, spun bond, spun lace, water jet, melt blow, needle punch, stitch blow, flash spinning, and tow opening. Paper can be made by any of acidic, neutral and alkaline.

  The base paper in the present invention may be subjected to a surface size press. The components of the surface size press solution include starch purified from natural plants, hydroxyethylated starch, oxidized starch, etherified starch, phosphate esterified starch, enzyme-modified starch, cold water soluble starch obtained by flash drying them, acrylic Acrylic surface sizing agents such as styrene / acrylic, styrene / maleic acid, styrene / olefin, acrylic / vinyl acetate, and olefinic surface sizing agents such as olefin / maleic acid and diisobutylene / maleic acid.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

The physical properties of the coated paper for printing in each example and comparative example were evaluated by the following methods.
<Evaluation method>
1) Printing unevenness The printing unevenness was evaluated by visually determining the printing surface of the obtained printed matter using a sheet-fed offset printing machine (DAIYA3H manufactured by Mitsubishi Heavy Industries, Ltd.), and evaluating the printing unevenness in a range of 1 to 5 points. However, in the present invention, 4 points and 5 points were the subject of the invention.
5 points: No gloss unevenness or ink acceptability unevenness is observed on the printed surface.
4 points: There is almost no gloss unevenness or ink acceptability unevenness on the printed surface.
3 points: Gloss unevenness and ink acceptability unevenness on the printed surface are conspicuous depending on the type of image.
2 points: Gloss unevenness and ink acceptability unevenness on the printed surface can be confirmed in any image.
1 point: Gloss unevenness and ink acceptability unevenness are very large on the printed surface.

2) Texture with a feeling of unevenness The texture with a feeling of unevenness was judged visually and evaluated by ◎, ○, Δ, and ×. However, in the present invention, ◎ and ○ are the objects of the invention.
A: The surface of the coated paper for printing has a feeling of unevenness, and the surface is uniformly uneven.
○: The unevenness on the surface of the coated paper for printing is slightly uneven, but the unevenness can be confirmed.
(Triangle | delta): Although the uneven | corrugated feeling of the coated paper surface for printing can be confirmed, it is very non-uniform | heterogenous.
X: The texture of unevenness can hardly be felt on the surface of the coated paper for printing.

3) Printability The printability was evaluated by visually determining the print surface of the obtained printed material using a sheet-fed offset printing machine (DAIYA3H manufactured by Mitsubishi Heavy Industries, Ltd.) in the range of 1 to 5 points. However, in the present invention, 4 points and 5 points were the subject of the invention.
5 points: There are no printing defects caused by troubles such as blocking during printing on the printing surface, no unprinted portions (white spots), and the ink density is sufficient.
4 points: The printed surface may have a slightly lower ink density depending on the image, but there are no printing defects or white spots.
3 points: Printing defects and white spots can be confirmed on the printing surface, and the ink density is generally low.
2 points: Print defects and white spots are conspicuous on the printed surface.
1 point: There are very many portions not printed on the printing surface.

<Base paper>
A base paper for coating having a basis weight of 89.0 g / m ² was prepared with the following composition. A mass part here is the solid content mass ratio of each material with respect to 100 mass parts of total pulp solid content. After paper making, machine calendar processing was performed and used as a base paper.
<Base paper formulation>
ECF bleached LBKP (freeness 440 mlcsf) 85 parts by mass ECF bleached NBKP (freeness 490 mlcsf) 15 parts by mass
Light calcium carbonate (indicated by ash content in base paper) 6.0 parts by mass Commercial cationized starch 1.0 part by mass Commercial cationic polyacrylamide yield improver 0.030 parts by mass Commercial softener (ester compound of polyhydric alcohol and fatty acid) ) 0.3 parts by mass

Example 1
The coating liquid for providing the outermost layer on the base paper was prepared as follows. A mass part here is a solid content mass ratio of each material with respect to 100 mass parts of total pigment solid content in a coating liquid. Commercially available heavy calcium carbonate FMT-97 (manufactured by Phimatech Co., Ltd.) 50 parts by mass, commercially available kaolin clay KAOGLOSS-90 (manufactured by Shiraishi Calcium Co., Ltd.) 50 parts by mass The pigment slurry was added and dispersed with a disperser at a solid content concentration of 62% by mass. To this pigment slurry, 10 parts by mass of a commercially available styrene-butadiene copolymer latex and 1.0 part by mass of a commercially available polyvinyl alcohol (NM-11, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) are added as an adhesive. 50 parts by mass was added, the pH was adjusted to 9.6 with sodium hydroxide, and the solid content concentration was adjusted to 52% by mass with adjusted water to obtain a coating solution for providing the outermost layer. The coating liquid thus prepared was directly applied onto the base paper using a shim sizer, which is a kind of film transfer coater, with a solid content mass of 12.0 g / m ² on one side and 24.0 g / m on both sides. A coating amount of ² was provided and dried. The smear paper produced in this manner was subjected to uneven processing at an operation speed of 100 m / min using an embossing roll produced by a meal engraving method to obtain a coated paper for printing. At this time, pressurization conditions were adjusted so that the arithmetic average roughness (Ra) of the coated paper for printing after unevenness processing was 6.2 μm, and the design of the embossing roll was selected so that the recess spacing was 310 μm. did. The pattern used was an irregular shape with no regularity called grain. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Example 2)
In Example 1, the coating amount of the outermost layer, solid mass 12.0 g / ^{m 2} per surface, from 24.0 g / ^{m 2} on both sides, solid mass 2.0 g / ^{m 2} per surface, both sides Example 1 was carried out in the same manner as in Example 1 except that the amount was changed to 4.0 g / m ² . The evaluation results of the obtained printing coated paper are shown in Table 1.

(Example 3)
In Example 1, the coating amount of the outermost layer, solid mass 12.0 g / ^{m 2} per surface, from 24.0 g / ^{m 2} on both sides, solid mass 20.0 g / ^{m 2} per surface, both sides The procedure was the same as in Example 1 except that the amount was changed to 40.0 g / m ² . The evaluation results of the obtained printing coated paper are shown in Table 1.

Example 4
In Example 1, pressurizing conditions such that the arithmetic average roughness (Ra) of the coated paper surface for printing after unevenness processing is 6.2 μm are set so that the arithmetic average roughness (Ra) is 3.6 μm. The same procedure as in Example 1 was performed except that the pressure conditions were changed. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Example 5)
In Example 1, pressurizing conditions such that the arithmetic average roughness (Ra) of the printed coated paper surface after the unevenness processing is 6.2 μm are set so that the arithmetic average roughness (Ra) becomes 8.0 μm. The same procedure as in Example 1 was performed except that the pressure conditions were changed. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Example 6)
Example 1 is the same as Example 1 except that the embossing roll design is such that the recess spacing on the surface of the coated paper for printing after unevenness processing is 310 μm, and the embossing roll design is such that the recess spacing is 120 μm. The same was done. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Example 7)
Example 1 is the same as Example 1 except that the embossing roll design is such that the recess spacing on the surface of the coated paper for printing after unevenness processing is 310 μm, and the embossing roll design is such that the recess spacing is 600 μm. The same was done. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Example 8)
In Example 1, the coating method for providing the outermost layer is changed from a shim sizer, which is one type of film transfer coater, to the curtain coater, the coating amount of the outermost layer is set to a solid content mass of 12.0 g / m ² per side, from 24.0 g / ^{m 2} on both sides, solid mass 8.0 g / ^{m 2} per surface, the 16.0 g / ^{m 2} on both sides, the arithmetic mean roughness of the coated printing paper surface after roughened (Ra ) Is 6.2 μm, and the embossing is such that the concave interval on the surface of the coated paper for printing after unevenness is 310 μm so that the arithmetic average roughness (Ra) is 5.4 μm. The same procedure as in Example 1 was performed except that the roll pattern was changed to an embossed roll pattern having a recess interval of 250 μm. The evaluation results of the obtained coated paper for printing are shown in Table 2.

Example 9
In Example 8, all was carried out in the same manner as in Example 8 except that the coating method for providing the outermost layer was changed from a curtain coater to a shim sizer which is a kind of film transfer coater. The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 10)
In Example 8, all was performed in the same manner as in Example 8 except that the coating method for providing the outermost layer was changed from the curtain coater to the air knife coater. The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 11)
In Example 8, all was performed in the same manner as in Example 8 except that the coating method for providing the outermost layer was changed from the curtain coater to the spray coater. The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 12)
In Example 8, all was performed in the same manner as in Example 8 except that the coating method for providing the outermost layer was changed from the curtain coater to the blade coater. The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 13)
In Example 8, the coating amount of the outermost layer, solid mass 8.0 g / ^{m 2} per surface, from 16.0 g / ^{m 2} on both sides, solid mass 4.0 g / ^{m 2} per surface, both sides Example 8 was carried out in the same manner as in Example 8 except that the amount was changed to 8.0 g / m ² . The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 14)
In Example 8, the coating amount of the outermost layer, solid mass 8.0 g / ^{m 2} per surface, from 16.0 g / ^{m 2} on both sides, solid mass 10.0 g / ^{m 2} per surface, both sides Example 8 was carried out in the same manner as in Example 8 except that the amount was changed to 20.0 g / m ² . The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 15)
In Example 8, the coating amount of the outermost layer, solid mass 8.0 g / ^{m 2} per surface, from 16.0 g / ^{m 2} on both sides, solid mass 3.0 g / ^{m 2} per surface, both sides Example 8 was carried out in the same manner as in Example 8 except that the amount was changed to 6.0 g / m ² . The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 16)
In Example 8, the coating amount of the outermost layer, solid mass 8.0 g / ^{m 2} per surface, from 16.0 g / ^{m 2} on both sides, solid mass 11.0 g / ^{m 2} per surface, both sides Example 8 was carried out in the same manner as in Example 8 except that the amount was changed to 22.0 g / m ² . The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 17)
The coating liquid for providing the undercoat layer was prepared as follows. A mass part here is a solid content mass ratio of each material with respect to 100 mass parts of total pigment solid content in a coating liquid. Commercially available heavy calcium carbonate FMT-90 (manufactured by Phimatech Co., Ltd.) 80 parts by mass, commercial kaolin clay KAOGLOSS-90 (manufactured by Shiraishi Calcium Co., Ltd.) 20 parts by mass, and commercially available polyacrylic acid dispersant 0.50 parts by mass The pigment slurry was added and dispersed with a disperser at a solid content concentration of 62% by mass. To this pigment slurry, 10 parts by mass of a commercially available styrene-butadiene copolymer latex and 2.0 parts by mass of commercially available urea phosphate esterified starch (MS4600 manufactured by Nippon Shokuhin Kako Co., Ltd.) are added as an adhesive, and further commercially available calcium stearate is added in an amount of 0.001. 50 parts by mass was added, the pH was adjusted to 9.6 with sodium hydroxide, and the solid content concentration was adjusted to 49% by mass with adjusted water to obtain a coating solution for providing an undercoat layer. The coating liquid thus prepared was directly applied onto the base paper using a shim sizer, which is a kind of film transfer coater, with a solid content mass of 7.0 g / m ^{2 on} one side and 14.0 g / m on both sides. A coating amount of ² was provided and dried. Using a blade coater onto the undercoat layer, coating of Example 1 solid weight 7.0 g / m 2 per one surface a coating liquid for providing the outermost layer ^described, 14.0 g / m ² on both sides And dried. The smear paper produced in this manner was subjected to uneven processing at an operation speed of 100 m / min using an embossing roll produced by a meal engraving method to obtain a coated paper for printing. At this time, pressurization conditions are adjusted so that the arithmetic average roughness (Ra) of the surface of the coated paper for printing after unevenness processing is 5.4 μm, and the design of the embossing roll is selected so that the recess spacing is 250 μm. did. The pattern used was an irregular shape with no regularity called grain. The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 18)
In Example 17, the coating method for providing the undercoat layer was changed from a shim sizer, which is a kind of film transfer coater, to a blade coater, and the coating method for providing the outermost layer was changed from a blade coater to an air knife coater. The same operation as in Example 17 was performed. The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 19)
In Example 17, the coating method for providing the undercoat layer was changed from a shim sizer, which is a kind of film transfer coater, to a blade coater, and the coating method for providing the outermost layer was changed from a blade coater to a curtain coater. The same operation as in Example 17 was performed. The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 20)
In Example 17, a coating method for providing an undercoat layer is applied from a shim sizer, which is a kind of film transfer coater, to a blade coater, and a coating method for providing an outermost layer is applied from a blade coater to an air knife coater. change application amount, solid mass 7.0 g / ^{m 2} per surface, from 14.0 g / ^{m 2} on both sides, solid mass 5.0 g / ^{m 2} per surface, the 10.0 g / ^{m 2} on both sides The same procedure as in Example 17 was performed except for the above. The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Example 21)
In Example 17, a coating method for providing an undercoat layer is applied from a shim sizer, which is a kind of film transfer coater, to a blade coater, and a coating method for providing an outermost layer is applied from a blade coater to an air knife coater. change application amount, solid mass 7.0 g / ^{m 2} per surface, from 14.0 g / ^{m 2} on both sides, solid mass 4.0 g / ^{m 2} per surface, the 8.0 g / ^{m 2} on both sides The same procedure as in Example 17 was performed except for the above. The evaluation results of the obtained coated paper for printing are shown in Table 2.

(Comparative Example 1)
In Example 1, the coating amount of the outermost layer, solid mass 12.0 g / ^{m 2} per surface, from 24.0 g / ^{m 2} on both sides, solid mass 1.8 g / ^{m 2} per surface, both sides The procedure was the same as in Example 1 except that the amount was changed to 3.6 g / m ² . The evaluation results of the obtained printing coated paper are shown in Table 1.

(Comparative Example 2)
In Example 1, the coating amount of the outermost layer, solid mass 12.0 g / ^{m 2} per surface, from 24.0 g / ^{m 2} on both sides, solid mass 22.0 g / ^{m 2} per surface, both sides The procedure was the same as in Example 1 except that the amount was changed to 44.0 g / m ² . The evaluation results of the obtained printing coated paper are shown in Table 1.

(Comparative Example 3)
In Example 1, pressurizing conditions such that the arithmetic average roughness (Ra) of the surface of the coated coated paper for printing after unevenness processing is 6.2 μm are set so that the arithmetic average roughness (Ra) becomes 3.2 μm. The same procedure as in Example 1 was performed except that the pressure conditions were changed. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Comparative Example 4)
In Example 1, pressurizing conditions such that the arithmetic average roughness (Ra) of the surface of the coated coated paper for printing after unevenness processing is 6.2 μm are set so that the arithmetic average roughness (Ra) is 8.5 μm. The same procedure as in Example 1 was performed except that the pressure conditions were changed. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Comparative Example 5)
Example 1 is the same as Example 1 except that the embossing roll design is such that the concave spacing on the surface of the coated paper for printing after unevenness processing is 310 μm, and the embossing roll design is such that the concave spacing is 90 μm. The same was done. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Comparative Example 6)
Example 1 is the same as Example 1 except that the embossing roll design is such that the concave spacing on the surface of the coated paper for printing after unevenness processing is 310 μm, and the embossing roll design is such that the concave spacing is 650 μm. The same was done. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Comparative Example 7)
In Example 1, pressurizing conditions such that the arithmetic average roughness (Ra) of the surface of the coated coated paper for printing after unevenness processing is 6.2 μm are set so that the arithmetic average roughness (Ra) becomes 3.2 μm. The embossing roll design was changed from an embossing roll design with a recess spacing of 310 μm to an embossing roll design with a recess spacing of 650 μm. Performed as in Example 1. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Comparative Example 8)
In Example 1, pressurizing conditions such that the arithmetic average roughness (Ra) of the surface of the coated coated paper for printing after unevenness processing is 6.2 μm are set so that the arithmetic average roughness (Ra) is 8.5 μm. The embossing roll design was changed from an embossing roll design with a concave spacing of 310 μm to an embossing roll design with a concave spacing of 90 μm. Performed as in Example 1. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Comparative Example 9)
In Example 1, after the outermost layer was provided, the uneven processing was not performed, and any other surface processing was not performed, and this state was used as the coated paper for printing. The arithmetic average roughness (Ra) of the obtained printing paper surface was 2.9 μm. The evaluation results of the obtained printing coated paper are shown in Table 1.

(Comparative Example 10)
In Example 1, after providing the outermost layer, the uneven process was not performed, and a super calendar process was performed instead. The arithmetic average roughness (Ra) of the obtained printing paper surface was 2.1 μm. The evaluation results of the obtained printing coated paper are shown in Table 1.

  Table 1 shows the conditions and evaluation results of Examples 1 to 7 and Comparative Examples 1 to 10.

  Table 2 shows the conditions and evaluation results of Examples 8 to 21.

As is apparent from the results in Table 1, in the coated paper for printing having at least one layer on the base paper and a coating layer mainly composed of a pigment and an adhesive, the outermost layer has a solid content mass of 2.0 g per side. / M ² or more and 20.0 g / m ² or less, and the outermost layer is then provided with an arithmetic average roughness (Ra) defined by JIS B 0601-2001 of 3.6 μm or more and 8.0 μm. Hereinafter, by applying the unevenness process so that the interval between the recesses is 120 to 600 μm, there is provided a textured printing coated paper having a texture with no unevenness of gloss on the printed surface and excellent printability. . Preferably, the outermost layer is provided with a coating amount in a range of solid content mass of 4.0 g / m ² or more and 10.0 g / m ² or less by one of an air knife coater, a film transfer coater, a curtain coater, and a spray coater. As a result, there is provided a coated paper for printing having a texture with a feeling of unevenness that is free from uneven glossiness on the printing surface and excellent in printability. Preferably, at least one layer or more is provided between the outermost layer and the base paper, and an undercoat layer having a coating amount of 5.0 g / m ² or more of solid content per side is provided by a blade coater. Provided is a coated paper for printing having a texture with no unevenness in gloss and excellent printability.

Claims (3)

From one or more layers to the base paper, the coated paper for printing having a coating layer mainly containing a pigment and an adhesive, the outermost layer mass 2.0 g / m ² or more solids per side content 20.0 g / m ² Provided with the coating amount in the following range, and then on the outermost layer, the arithmetic average roughness (Ra) defined in JIS B 0601-2001 is 3.6 μm or more and 8.0 μm or less, and the recess spacing defined below. A coated paper for printing, which is subjected to uneven processing so that the thickness becomes 120 to 600 μm.
The distance between the recesses is the horizontal distance between the point recognized as the deepest part of the recess and the point at the deepest part of the recess closest to that point in the contour curve between two points at an arbitrary 1.0 mm interval. The average of the values obtained by performing this measurement 32 times is used. Note that the recess is a region with a height difference of 12 μm or more within a distance of 200 μm in the horizontal direction from the point that can be recognized as the minimum height point in the contour curve between the two points of 1.0 mm above. In this case, an area centered on the deepest part is shown.
The coated paper for printing according to claim 1, wherein the outermost layer has a solid content mass of 4.0 g / m ² or more and 10.0 g / m ² or less per side by any one of an air knife coater, a film transfer coater, a curtain coater, and a spray coater. The coated paper for printing according to claim 1, wherein the coated paper is provided at a coating amount in the range of 5 to 10. 2. The coated paper for printing according to claim 1, wherein at least one layer is provided between the outermost layer and the base paper, and an undercoat layer having a coating amount of 5.0 g / m ² or more of solid content per side is provided by a blade coater. The coated paper for printing according to claim 1.