JP4873973B2 - Method for producing coated paper for gravure printing and coated paper - Google Patents

Description

  The present invention relates to a method for producing a coated paper for gravure printing having excellent white paper appearance and excellent gravure printability, and the coated paper.

  Gravure printing is an intaglio printing method in which ink in a concave portion of a plate is transferred under pressure and has excellent gradation reproducibility, and is therefore used in commercial printing fields such as magazines, catalogs and pamphlets. In gravure printing, there is a case where a halftone dot called speckle does not transfer normally when the plate is a hard metal roll compared to offset printing and the plate surface does not completely adhere to the paper during printing. When there are many speckles, that is, the print quality is deteriorated.

  In order to suppress the generation of speckles, the smoothness and cushioning properties of the coated paper are important. This is because if the smoothness is high, the contact with the plate becomes dense, and if the cushioning property is high, the paper is deformed by the printing pressure during printing and the adhesion to the paper is increased.

  In order to improve the smoothness of the coating layer surface of the coated paper for gravure printing, it is generally effective to add pigments with high aspect ratio (delaminated clay, talc, etc.) to the coating layer composition It is said that. However, blending many pigments with a high aspect ratio in the coating layer composition increases the viscosity of the coating solution, making it difficult to handle during preparation and causing coating defects such as streak and scratch. Cheap. For this reason, it is the present condition that solid content concentration of a paint cannot be made very high, As a result, it becomes necessary to make drying conditions strong, and it leads to high cost. In addition, pigments such as delaminated clay and talc with high aspect ratios were used in large amounts, as can be seen from the fact that they are generally used in low-gloss applications such as matte coated paper. In some cases, the glossiness of the white paper is low, so that it is not suitable for applications that require high white paper glossiness.

  In addition, for the purpose of preventing speckle generation and improving opacity, a method of using calcined clay in combination with other pigments is also known, but calcined clay is inferior in fluidity, so the viscosity of the coating liquid increases. This may cause coating defects such as streaks and scratches and may deteriorate the workability of the coater. For this reason, the solid content density | concentration of a coating material cannot be made very high.

  On the other hand, a method is known in which an organic pigment such as a plastic pigment is used to impart high white paper gloss, speckle prevention effect, opacity, and the like (see Patent Document 1). However, since organic pigments are expensive compared to inorganic pigments, the cost is high, and the coating liquid added with organic pigments tends to increase in viscosity under high shearing force, resulting in poor coating such as streak and scratch. Prone to cause. For this reason, it is the present condition that solid content concentration of a paint cannot be made very high, As a result, it becomes necessary to strengthen drying conditions, and there is a problem that it leads to high cost.

  In addition, as a technique for mechanically smoothing the surface of the coating layer of the coated paper for gravure printing and imparting white paper glossiness, a high pressure treatment using a super calendar is usually performed. Surface treatment with a supercalender can improve the smoothness and white paper gloss, but at the same time the density of the coated paper is increased, and the opacity, stiffness and cushioning properties of the coated paper are lost. When the opacity is insufficient, the printed pattern is transmitted and affects the printed pattern on the back surface, or the feeling of blank paper on the back surface is impaired, resulting in a decrease in quality. In order not to lose opacity and stiffness, it is necessary to reduce the pressure treatment, but usually it causes a decrease in the glossiness of white paper and an increase in speckles during gravure printing. The current situation is that pressure cannot be reduced.

  In printing paper other than gravure paper, in recent years, many methods using a high-temperature soft nip calender, which has come to be used in place of the conventional supercalender, have been proposed, increasing the finishing speed, printing glossiness, opacity, It has been reported that rigidity and the like are relatively improved. However, when only this method is used, the glossiness can be increased efficiently, but because it is processed at a high temperature, it is easily affected by moisture in the paper, and if the moisture profile in the width direction is not uniform, the glossiness of the white paper This causes a slight unevenness of the ink and uneven ink deposit after printing, which is not preferable in appearance. Further, when the surface property of the coated paper before being calendered at a high temperature is inferior, similarly, a slight unevenness in the glossiness of the white paper and unevenness in the ink deposit density are generated, which is not preferable in appearance.

  As a countermeasure like this, for example, it is treated with a brush roll and a metal roll in which fibers are planted immediately before or after the treatment with a high temperature calendar, and the surface basis weight unevenness, coating amount unevenness, etc. are polished to solve the slight glossiness unevenness. However, it is difficult to adjust the moisture unevenness and the ink unevenness unevenness is insufficiently improved. there were.

In view of the above background, it has been desired to develop a coated gravure paper having a high blank paper glossiness and good printing quality.
JP-A 64-20396 JP-A-9-228298

  In view of such a situation, the object of the present invention is to provide a coated paper for gravure printing with improved speckles, high glossiness of a blank paper, and small glossiness unevenness and ink unevenness after printing. There is to do.

As a result of earnest research on the above problems, the present inventors have made clay as a pigment in an amount of 100 wt.% Of inorganic pigment in a method for producing a coated paper for printing in which a coating liquid containing a pigment and an adhesive is coated on a base paper. After coating a coating solution containing 50 parts by weight or more per part, and containing 5 parts by weight or less of starch as an adhesive with respect to 100 parts by weight of the total amount of inorganic pigment, heat to an elastic roll and 40 ° C to less than 100 ° C Pass through a calendar made of a metal roll, and pass through a calendar made of a metal roll heated to a temperature of at least 100 ° C. and higher than the temperature of the metal roll by 20 ° C. or higher. Thus, the inventors have found that speckle during gravure printing is reduced and high white paper glossiness can be obtained, and the present invention has been achieved.
In the present invention, a coating liquid containing 50 parts by weight or more of clay as a pigment on the base paper per 100 parts by weight of inorganic pigment is applied, and then an elastic roll and a metal roll heated to 40 ° C. or more and less than 100 ° C. After passing through the calendar, it is important to finish by passing through a calendar composed of a metal roll heated to an elastic roll and 100 ° C. or more and 20 ° C. or more higher than the temperature of the metal roll. After coating, once the paper is passed through a calendar heated to 40 ° C or more and less than 100 ° C, the moisture profile in the coated paper becomes more uniform and the coated paper surface becomes smoother. The expression is low, and glossiness unevenness does not occur at this point. After that, by passing a calendar heated to 20 ° C. or higher and 100 ° C. or higher from the roll temperature, the glossiness of the white paper is high, the gloss unevenness is small, the ink unevenness after printing is small, and the speckle is excellent. Thus, a coated paper for gravure printing having gravure printing suitability is obtained.

  According to the present invention, speckle is improved, white paper glossiness is high, fine gloss unevenness and ink inking unevenness after printing can be obtained, and a gravure coated coated paper having excellent printability can be obtained, In addition, the operability is good, the printability is excellent, and the coated paper for gravure printing can be produced efficiently.

  The coating composition used for the gravure coated coated paper of the present invention is described below. In the present invention, in order to improve the smoothness and gravure printability of the coated paper, the clay contains 50 parts by weight or more per 100 parts by weight of the inorganic pigment, more preferably 65 parts by weight or more, Preferably it is 80 weight part or more. When the amount is less than 50 parts by weight, the smoothness becomes low, and speckles during gravure printing increase. Moreover, as a preferable average particle diameter of the clay to be used, 0.2-3.0 micrometers is preferable, More preferably, it is 0.4-2.5 micrometers. When it is smaller than 0.2 μm, the specific surface area of the pigment is increased, so that the viscosity of the coating is increased, and the coating suitability is inferior, which is not preferable from an operational viewpoint. If it is larger than 3.0 μm, the glossiness of the white paper tends to be low, which is not preferable for achieving the object of the present invention. In addition, the use of engineered clay improves printability and gloss unevenness. In addition, the average particle diameter of this invention is calculated | required by measuring the value by the 50% part of a volume cumulative distribution by measuring with the laser method (Malvern Co., Ltd. master sizer S type).

  Moreover, as a pigment used for this invention, it can use together with the other pigment conventionally used for coated papers in the range which does not impair the objective of invention. For example, heavy calcium carbonate, light calcium carbonate, talc, titanium dioxide, barium sulfate, calcium sulfate, zinc oxide, silicic acid, silicate, colloidal silica, satin white and other inorganic pigments, and plastic pigments and other organic pigments. These pigments can be used in combination of one or more if necessary. In order to increase the efficiency of increasing the glossiness of the blank paper using a calendar heated to a high temperature, it is preferable to use it together with a plastic pigment. The amount of the plastic pigment is preferably 2 to 30 parts by weight, more preferably 2 to 20 parts by weight, and still more preferably 3 to 15 parts by weight with respect to 100 parts by weight of the inorganic pigment. When blending more than 30 parts by weight, the plastic pigment melts when passing through a calendar heated to a high temperature, and sticks to a metal roll, which tends to cause trouble. After coating, passing the paper once through a calender consisting of an elastic roll and a metal roll heated to 40 ° C. or more and less than 100 ° C. makes the moisture profile in the coated paper more uniform and smoothes the coated paper surface. Therefore, it leads to reduction of sticking of the paper to the metal roll at the time of calendar processing at high temperature.

  In this invention, it is preferable to provide 1-3 coating layers, and when providing two or more layers, it is preferable to mix | blend a plastic pigment with the outermost layer.

  As the plastic pigment used in the present invention, a solid type, a hollow type, a core-shell type, or the like can be used singly or in combination of two or more as required. As the constituent polymer component of the plastic pigment, a monomer such as styrene and / or methyl methacrylate is preferably used as a main component, and other monomers copolymerizable with these as necessary. Examples of the copolymerizable monomer include olefinic aromatic monomers such as α-methylstyrene, chlorostyrene, and dimethylstyrene, methyl (meth) acrylate, ethyl (meth) acrylate, and butyl (meth) acrylate. Monoolefin monomers such as 2-ethylhexyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylonitrile, and monomers such as vinyl acetate. If necessary, for example, olefinic unsaturated carboxylic acid monomers such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, hydroxyethyl, hydroxyethyl methacrylate, hydroxypropyl acrylate Olefinic unsaturated hydroxy monomers such as hydroxypropyl methacrylate, acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N-methoxymethylacrylamide and other olefinic unsaturated amide monomers, divinylbenzene, etc. These dimer vinyl monomers can be used singly or in combination of two or more. These monomers are examples, and any other copolymerizable monomer may be used.

    As an adhesive used for the coating layer of the present invention, it is necessary to make starch 5 parts by weight or less with respect to 100 parts by weight of the inorganic pigment from the viewpoint of printability. By blending starch, the strength of the coating layer increases, but when blending 5 parts by weight or more with respect to 100 parts by weight of the pigment, the coating layer becomes stiff and the gravure printing suitability is poor. Various adhesives such as styrene / butadiene, styrene / acrylic, ethylene / vinyl acetate, butadiene / methyl methacrylate, and vinyl acetate / butyl acrylate are conventionally used for coated paper. Synthetic adhesives such as polymers, maleic anhydride copolymers, acrylic acid / methyl methacrylate copolymers; proteins such as casein, soy protein, synthetic proteins; oxidized starch, positive starch, urea phosphated starch, One or more ordinary adhesives for coated paper such as etherified starch such as hydroxyethyl etherified starch are appropriately selected and used. The total amount of these adhesives is preferably 3 to 15 parts by weight, more preferably 3 to 10 parts by weight with respect to 100 parts by weight of the inorganic pigment, from the viewpoint of printability and coating suitability. As the adhesive, it is preferable to use a copolymer latex having a glass transition temperature of −50 ° C. to 0 ° C. By using the thing of this range, it becomes a coating layer which has cushioning properties suitable for gravure printing.

  In addition, as additives to be blended as necessary, various auxiliary agents blended in ordinary coating materials such as dispersants, thickeners, water retention agents, antifoaming agents, water resistance agents, and coloring agents are suitable. Used. As the auxiliary used in the present invention, an acrylic synthetic water retention agent and hydroxyethyl cellulose are preferably used, and an associative acrylic synthetic water retention agent is more preferably used. The associative acrylic synthetic water retention agent functions to improve the water retention of the coating solution and to reduce the high shear viscosity of the coating solution. Therefore, it is suitable for high-speed coating, the paint is not pushed into the coating base paper during coating, the coating layer on the base paper is bulky, and the cushioning property of the coating layer is improved. The rate tends to be low. Hydroxyethyl cellulose has the same effect. In addition, when using an acrylic synthetic water retention agent and / or hydroxyethyl cellulose, the blending amount is preferably 0.1 to 1.0 part by weight with respect to 100 parts by weight of the inorganic pigment.

  The base paper of the present invention is blended with ordinary pulp, filler and the like. In the present invention, the type of pulp blended into the base paper is not particularly limited. For example, hardwood kraft pulp (hereinafter referred to as LBKP), softwood kraft pulp (hereinafter referred to as NBKP), thermomechanical pulp, groundwood pulp, waste paper pulp, and the like are used.

  In addition, as fillers to be blended in the base paper, known fillers such as heavy calcium carbonate, light calcium carbonate, kaolin, clay, talc, hydrated silicic acid, amorphous silicate, white carbon, titanium oxide, synthetic resin filler, etc. are used. can do. A compounding quantity is about 0 to 20 weight%. Further, if necessary, a sulfuric acid band, a sizing agent, a paper strength enhancer, a yield improver, a color pigment, a dye, an antifoaming agent, and the like may be contained.

The paper making method of the base paper is not particularly limited, and the paper making method using a known paper machine such as a long web paper machine, a gap former, a hybrid former (on-top former), etc. Any of the base papers that have been made may be used, and medium base papers containing recovered recovered paper pulp obtained from used newspapers can also be used. Also, a base paper pre-coated with starch, polyvinyl alcohol or the like using a size press, a bill blade, a gate roll coater, or a pre-metering size press can be used. The coating base paper, basis weight of 30 to 400 g / ^{m 2} to be used for general coated paper, preferably of the order of 40~200g / ^{m 2} is used as appropriate.

As a method of coating the coating liquid adjusted on the coating base paper, using a blade coater, bar coater, roll coater, air knife coater, reverse roll coater, curtain coater, size press coater, gate roll coater, etc. Or two or more layers are coated on one or both sides of the base paper. The coating amount is determined according to desired properties, but in the present invention, the range of 3 to 35 g / m ² is preferable per side, and more preferably 8 to 25 g / m ² .

  As a method for drying the wet coating layer, various methods such as a steam superheating cylinder, a heated hot air air dryer, a gas heater dryer, an electric heater dryer, and an infrared heater dryer are used alone or in combination.

    In the present invention, the coated paper thus obtained is passed through a calender composed of an elastic roll and a metal roll heated to 40 ° C. or more and less than 100 ° C., and then the elastic roll, 100 ° C. or more and the roll temperature. The paper is finished by passing it through a calendar made of a metal roll heated to a temperature 20 ° C. or higher compared to the above.

    In the present invention, the calendar process is first performed at a relatively low temperature, but by performing the low temperature process before the high temperature process, the moisture profile in the coated paper is made more uniform and the coated paper surface is also smooth. Then, the gloss unevenness can be suppressed by treating with a calender which is 20 ° C. or more higher than the roll temperature and heated to 100 ° C. or more. For this reason, the initial low temperature treatment is not sufficient to make the moisture profile uniform when the temperature is lower than 40 ° C., and when the temperature is higher than 100 ° C., it is the same as the high temperature treatment with moisture unevenness. Ink deposit unevenness occurs, which is not preferable. As a more preferable range, it is 40 to 80 degreeC, More preferably, it is 50 to 80 degreeC.

    The surface temperature of the metal roll subjected to the high temperature treatment performed after the low temperature treatment is preferably 120 ° C. or higher and 300 ° C., more preferably 130 ° C. or higher and 250 ° C. or lower. If the moisture content of the coated paper is appropriate, the base paper or the coated layer can be smoothed by using a metal roll heated to 100 ° C. or higher, and a high gloss coated paper can be obtained. . The moisture content of the coated paper before the high temperature treatment is preferably 5 to 8%.

    Further, the treatment linear pressure of the calendar in the present invention is 100 ° C. or more with respect to the average of the linear pressure when passing through a calendar composed of an elastic roll and a metal roll heated to 40 ° C. or more and less than 100 ° C. In addition, it is preferable that the average linear pressure when passing through a calendar made of a metal roll heated to 20 ° C. or more higher than the roll temperature is 20 kg / cm or more. This is because the first calendar process performed at a relatively low temperature is intended to adjust the moisture profile and surface properties of the coated paper compared to the high temperature calendar process performed later. This is preferable in terms of preventing density unevenness and reducing the density. A preferred linear pressure range is 10 to 250 Kg / cm. In addition, the treatment linear pressure of the high temperature calendar is preferably higher than the low temperature calendar treatment by 20 Kg / cm or more, more preferably 40 Kg / cm or more, in order to improve the white paper glossiness. Making the average linear pressure 20 Kg / cm or more higher than the low temperature calendering is a comparison of values obtained by averaging the linear pressures at the respective nips when the low temperature treatment and the high temperature treatment are multistage. A preferable linear pressure range is 30 to 500 kg / cm. Moreover, as a preferable condition when using a high temperature soft nip calender as the high temperature calendar treatment, for example, the Shore D hardness of the elastic roll is 80 to 100, preferably 85 to 95, and the paper passing speed is 400 to 3000 m / min. A linear pressure of 30 to 500 Kg / cm and a pre-calendar coated paper moisture of 5 to 8% are preferable. The number of nips for low temperature treatment and high temperature treatment is 1 nip or more, preferably 1 to 6 nips, more preferably 2 to 6 nips for low temperature treatment, and 1 nip or more, preferably 1 to 6 nips for high temperature treatment. Is 2-4 nips. In the present invention, after the high temperature treatment, low temperature calendar treatment may be performed within a range not impairing the effects of the present invention.

  In the present invention, the treatment is performed with a plurality of calendar rolls, and as a form thereof, a plurality of calendars in which a pair of elastic rolls and metal rolls are installed, a calendar roll is vertically or obliquely arranged. Either of the arranged multistage type may be used. However, the most preferable form of the calendar in the present invention is a multistage form, and further, a structure that does not have a mechanism for suppressing the weight of the upper roll from being applied to the lower roll. By adopting this form, it is possible to perform relatively low temperature and low linear pressure processing at the upper stage, and rationally perform high temperature and high linear pressure processing at the lower stage, and it does not take up space in terms of equipment. There are advantages.

  Furthermore, the most preferable calendar form in the present invention will be described. Calendar rolls are arranged vertically, and the number of rolls is 10 or 12. At this time, the types of rolls are, from above, metal roll (A), elastic roll, (B), metal roll (C), elastic roll (D), metal roll (E), elastic roll (F), metal roll ( G), elastic roll (H), elastic roll (I), metal roll (J), elastic roll (K), and metal roll (L) in this order (except for E and F in the case of 10 rolls). At this time, a metal roll (G) and a metal roll (J) are heated at 100 degreeC or more, and another metal roll is heated at 40 to 100 degreeC. By taking this form, the moisture profile is made more uniform by the low temperature and low linear pressure treatment with the metal roll (A) to the metal roll (E), and the coated paper surface is appropriately smoothened. Thereafter, one side of the coated paper can be subjected to high temperature treatment with the metal roll (G), and the other side can be subjected to high temperature treatment with the metal roll (J). At this time, the surface treated with the metal roll (J) (surface B) is treated with a higher linear pressure than the surface treated with the metal roll (G) (surface A). Unlike surface B, the number of times of low temperature / low linear pressure treatment is high, so that there is little difference in glossiness between the front and the back.

  The effect of the present invention can be exhibited more particularly when a glossy coated paper having a white paper glossiness of 75% or more is produced.

EXAMPLES The present invention will be specifically described below with reference to examples, but it is needless to say that the present invention is 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 printing based on the evaluation method as shown below.
<Evaluation methods>
(1) Glossiness of blank paper: Measured based on JIS P 8142.
(2) Smoothness: JAPAN TAPPI No. 5 Measured based on “Smoothness / air permeability test method for paper and paperboard by air micrometer type tester”.
(3) Number of speckles: Using a Ministry of Finance gravure printing machine (manufactured by Kumagai Riki Kogyo Co., Ltd.), printing was performed at a printing speed of 40 m / min and a printing pressure of 10 kgf / cm. No situation was assessed visually.

(Double-circle): Very good, (circle): Good, (triangle | delta): Somewhat inferior, X: Somewhat inferior (4) Micro gloss unevenness: The situation where the gloss unevenness did not generate | occur | produce was visually evaluated in the following four steps.

(Double-circle): Very good, (circle): Good, (triangle | delta): Somewhat inferior, X: Somewhat inferior (5) Uneven ink unevenness: The condition which the uneven ink unevenness after gravure printing did not generate | occur | produce was visually evaluated in the following four steps.

◎: Extremely good, ○: Good, △: Slightly inferior, ×: Slightly inferior
[Example 1]
Inorganic pigment consisting of 82 parts of engineered clay (IPERYS Capim DG, average particle size 1.19 μm) and 18 parts of engineered clay (IMERYS Contour 1500, average particle size 1.95 μm) Then, 0.2 part of sodium polyacrylate was added and dispersed with a serie mixer to prepare an inorganic pigment slurry. To the prepared slurry, 10 parts of hollow plastic pigment (AE-851 manufactured by JSR) was added, 7 parts of styrene / butadiene copolymer latex (glass transition temperature-40 ° C.) was added, and acrylic synthetic water retention agent 0.4 Part and water were further added to obtain a coating solution having a solid concentration of 65%.

The coated base paper was a medium quality paper having a basis weight of 42 g / m ² containing 3% by weight of light calcium carbonate as a filler and 45% by weight of mechanical pulp as a papermaking pulp.

The above-mentioned base paper is coated on both sides with a blade coater at a coating speed of 500 m / min so that the coating amount per side of the above-mentioned coating liquid is 9 g / m ² , Was dried to 5%.
After drying, a calendar process was performed with the roll arrangement, metal roll temperature, and nip pressure shown in FIG. 1 and Table 1- (1) to obtain a coated paper for printing. At this time, the elastic roll shore D hardness is 92 and the paper passing speed is 600 m / min.
[Example 2]
In Example 1, instead of 82 parts of engineered clay (Capime DG manufactured by IMERYS, average particle diameter 1.19 μm) and 18 parts of engineered clay (Contour 1500 manufactured by IMERYS, average particle diameter 1.95 μm), fine clay ( Except for changing to 65 parts by J.M.HUBER JapanGloss, average particle size 0.43 μm) and 35 parts by weight of heavy calcium carbonate slurry (FMT-97 made by PMMA Tech) (solid content), the same as in Example 1. The coated paper was obtained by the method.
[Example 3]
In Example 1, a coated paper was obtained in the same manner as in Example 1 except that the calendar treatment of the coated paper was changed from Table 1- (1) to Table 1- (2).
[Example 4]
In Example 1, instead of 82 parts of engineered clay (Capim DG manufactured by IMERYS, average particle diameter 1.19 μm) and 18 parts of engineered clay (Contour 1500 manufactured by IMERYS, average particle diameter 1.95 μm), engineered clay (Capime DG manufactured by IMERYS) 41 parts, Engineered clay (Contour 1500 manufactured by IMERYS Co., Ltd.) 9 parts and heavy calcium carbonate slurry (FMT-97 manufactured by PMMA Tech, average particle size 0.58 μm) 50 parts (solid content) A coated paper was obtained in the same manner as in Example 1 except for the change.
[Comparative Example 1]
In Example 1, instead of 82 parts of engineered clay (Capim DG manufactured by IMERYS, average particle diameter 1.19 μm) and 18 parts of engineered clay (Contour 1500 manufactured by IMERYS, average particle diameter 1.95 μm), engineered clay Example 1 except for changing to 20.5 parts (Capim DG manufactured by IMERYS), 4.5 parts engineered clay (Contour 1500 manufactured by IMERYS) and 75 parts heavy calcium carbonate slurry (FMT-97 manufactured by PMMA Tech). Coated paper was obtained in the same manner as above.
[Comparative Example 2]
In Example 1, a coated paper was obtained in the same manner as in Example 1 except that the calendar treatment of the coated paper was changed from Table 1- (1) to Table 1- (3).
[Comparative Example 3]
In Example 1, a coated paper was obtained in the same manner as in Example 1 except that the calendar treatment of the coated paper was changed from Table 1- (1) to Table 1- (4).
Table 1 shows the calendar processing conditions, and Table 2 shows the evaluation results.

It is explanatory drawing which showed the calendar processing method.

Explanation of symbols

1 Metal roll
2 Elastic (resin) roll 3 High temperature metal roll

Claims (3)

A coating liquid containing a pigment and an adhesive, the clay containing 50 parts by weight or more of clay as a pigment per 100 parts by weight of an inorganic pigment and 5 parts by weight or less of starch as an adhesive with respect to 100 parts by weight of the inorganic pigment After the liquid is coated on the base paper, it is passed through a calendar composed of an elastic roll and a metal roll heated to 40 ° C. or more and less than 100 ° C., and the coated paper having a moisture content of 5 to 8% is further applied. A method for producing a coated paper for gravure printing, characterized by passing through a calender consisting of an elastic roll and a metal roll heated to 100 ° C. or more and higher than the temperature of the metal roll by 20 ° C. or more. .   The average linear pressure when passing through a calender composed of an elastic roll and a metal roll heated to 40 ° C. or higher and lower than 100 ° C. is 100 ° C. or higher and higher than the temperature of the metal roll by 20 ° C. or higher. The method according to claim 1, wherein the method is 20 kg / cm or more higher than the average linear pressure when passing through a calendar made of a metal roll heated to a temperature.   The method of Claim 1 or 2 which contains 2-30 weight part of plastic pigments with respect to 100 weight part of inorganic pigments in a coating liquid.

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