JP2856021B2 - Manufacturing method of coated paper for printing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a coated paper for printing. More specifically, the present invention relates to a method for producing a coated printing paper having high rigidity, stiffness, and excellent water resistance.

[0002]

2. Description of the Related Art Demand for coated paper for printing is increasing in books, calendars, catalogs, posters, and the like with the increase in color of printed materials.

[0003] On the other hand, printed paper is folded and glued to form a decorative box, or this paper is used as a backing paper and another paper such as a photograph, a drawing, or a sample is stuck thereon. It has increased remarkably recently.

As the glue or adhesive used in these applications, the solvent (oil type) type is gradually becoming less preferred from the viewpoint of environmental pollution, and the aqueous type is widely used recently.

However, when a water-based glue is applied to a conventional printing coated paper, the water resistance is insufficient, so that the paper is curled on a processing machine to significantly impede the workability. The value of the product has been reduced due to swelling or waving (so-called unevenness).

In applications such as posters, paper exposed to the outdoors or posted indoors for a long period of time in places where air conditioning is not sufficient may cause the paper to undulate or sag, thereby significantly impairing the appearance. Many cases occurred. For this reason, posters using synthetic paper as a base material have been put to practical use, but in this case, there is a problem in terms of waste disposal, and there is a problem of causing pollution.

As a method for increasing the water resistance of coated paper for printing, it is widely used to blend a so-called water-proofing agent such as urea-formaldehyde resin, glyoxal, zirconium ammonium carbonate or the like into a coating solution. (See Tech Times, “Handbook of Latest Paper Processing,” page 469, 1988). However, these water-proofing agents have a limited effect of exhibiting water resistance, and when they are incorporated in a large amount in a coating solution, they increase the viscosity of the coating solution, which makes the coating difficult. There is.

[0008] As a paper wax processing method, a surface coating method using a paraffin wax, a polypropylene wax, a microcrystalline wax or the like, an impregnation method, and a laminating method are also known. (Refer to the above-cited reference, "Handbook of Latest Paper Processing", page 516). However, it is not practical to apply these methods to the coated printing paper of the present invention because the water resistance is too strong and the adhesion of the aqueous paste is hindered.

An example in which a wax emulsion having a melting point of 50 to 100 ° C. is blended with a coating liquid composition and used (Japanese Patent Laid-Open No.
JP-A-118016) and an example of blending a high-melting wax emulsion (see JP-A-53-41509) are disclosed. Not suitable for application to papermaking.

On the other hand, there is disclosed a technique for passing coated paper through a finishing device comprising a heated drum having a smooth metal surface and an elastic backing roll to impart gloss and smoothness to the surface of the paper web. (Special Publication 63-
No. 56360).

In this method, the pressure on the paper web is at least 13,780 KN / M ² (2,000 psi, 1 psi).
700 KN / M (4000 lb / line inch, 71 K) to form a nip with 41 Kg / cm ^2.
It discloses a technique of pressing against a drum with a force of up to 5 kg / cm), but there is no specific example of a coating liquid composition, and moreover, it suggests the application of a wax emulsion as in the present invention. Is not at all. In addition, the purpose is to impart gloss and smoothness to the paper surface, and only a technique completely different from the method for producing a coated paper for printing having excellent water resistance and rigidity, so-called stiffness, is disclosed. .

The stiffness of paper is a physical property called stiffness, waist, etc. For example, in applications such as the text paper of a book, it is rather preferred that the stiffness (ie, softness) of a paper is lower as it is easier to turn pages. Although there is a tendency, high stiffness is required for uses such as covers, boxes, mounts, and cards.

In order to express the stiffness, there are known a flexure method, a Clark method, a Taber method, a Gurley method, a Young's modulus method, and the like, which are expressed by an angle of a tip that hangs down when the paper is stretched horizontally by the weight of the paper itself. See Pulp and Paper Association, Ed., Pulp and Paper Types and Test Methods, pp. 185-192, Showa 41).

On the other hand, since these measured values vary depending on the thickness, basis weight, etc. of the paper, it is often difficult to grasp the stiffness only with the numerical values. In fact, the method of knowing stiffness sensuously has been simple and convenient since ancient times.

[0015] Since the apparent rigidity of paper increases as its thickness or basis weight increases, for applications requiring rigidity, it is often necessary to adjust the thickness and basis weight for convenience. There is naturally an upper limit to the paper weight and the basis weight, and there is a limit to imparting rigidity to paper by such a method.

In particular, in the case of coated paper for printing, it is common practice to calender the coated paper to finish the surface of the coated paper. There is a strong tendency to decrease, and countermeasures are desired.

As described above, despite the strong demand in the market for a coated paper for printing having both excellent water resistance and rigidity, an appropriate method for producing such coated paper is still being developed. It has not been done yet.

[0018]

In view of the above situation, the present inventors have conducted intensive studies on the coating liquid composition of the coated paper for printing and the method of finishing the paper coated with the coating liquid. By including a wax emulsion in the working liquid composition and specifying the nip conditions and the surface temperature of the drum when finishing the surface by passing coated paper between the finishing drum and the elastic roll, the paper originally has It has been found that water resistance can be sufficiently exhibited without significantly lowering the rigidity, and the present invention has been completed.

Therefore, an object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to have a high rigidity and a so-called waist,
An object of the present invention is to provide a production method capable of obtaining a coated paper for printing having good water resistance and good printability.

[0020]

According to the present invention, a coating composition comprising a pigment, an adhesive and an auxiliary is applied on a paper substrate,
After drying the formed coating layer, in a method for producing a coated printing paper for finishing by passing through a nip between a smooth metal finishing drum and an elastic backing roll, (1) in the coating liquid composition A wax emulsion containing 0.5 to 8% of the total solid content of the coating liquid is contained.
-5 cm and a pressing pressure of 10-100 kg / cm ² , and (3) the surface temperature of the metal finishing drum is 100-190 ° C. .

In the present invention, a coating liquid composition containing a wax emulsion is used as a base paper (hereinafter, referred to as base paper) provided with an undercoat layer containing a pigment and an adhesive as main components on base paper. After forming a coating layer by drying and coating, the nip width, nip pressing pressure, and the surface temperature of the metal drum of the finishing device are adjusted according to the conditions of the present invention. It should be set to finish.

The wax emulsion used in the present invention is used for various purposes in a wide range of industrial fields, and its intended functions are water resistance, water repellency, softening, slipperiness, polishing properties, and metal surface. Natural waxes such as animal beeswax, vegetable tree wax, carnauba wax, mineral montan wax, petroleum paraffin wax, and polyethylene wax synthesized from ethylene etc. Waxes (Tech Times, “Chemical Encyclopedia of Paper and Processing,” p. 173, 1991
Is emulsified (emulsified) with an anionic, cationic, nonionic, or amphoteric surfactant. In addition to a wax alone, a special wax emulsion emulsified using a combination of wax and various synthetic resins can be used for the present invention.

Alternatively, an alkali salt of a partial ester of a vinyl aromatic compound-maleic acid compound copolymer esterified with a monohydroxy organic compound is used as an emulsifier, and a mixture of a wax and a hydrocarbon resin is emulsified in water. Wax emulsion sizing agent (Japanese Patent Publication No. Sho 61-
No. 8105) can also be used.

In the present invention, any one or more wax emulsions can be appropriately selected from the above wax emulsions.
Those having a temperature of 50 ° C, especially 60 to 120 ° C, are preferably used.

The amount of the wax emulsion in the coating liquid composition of the present invention is 0.5 to 0.5 per solid content of the coating liquid.
8%, preferably 1 to 6%. When the amount of the wax emulsion is less than 0.5%, the water resistance of the obtained coated paper becomes insufficient, and when the amount exceeds 8%, the slipperiness of the paper becomes excessive and handling becomes difficult. It becomes difficult, the rigidity decreases, and the printing ink printing tends to be uneven,
It is no longer suitable as a coated paper for printing.

The pigment used in the coating solution for the present invention includes kaolin, clay, calcium carbonate, titanium oxide, aluminum hydroxide, zinc oxide, barium sulfate, calcium sulfate, talc, silica, plastic pigment, satin white, and the like. Is appropriately selected and selected from among the general coating pigments.

Examples of adhesives include casein, soybean protein, yeast protein, starch, oxidized and esterified starch, etherified starch, cationized starch, modified starch such as enzyme-modified starch, natural adhesives such as cellulose derivatives, and styrene. Conjugated diene polymer latex such as butadiene copolymer, methyl methacrylate-butadiene copolymer, acrylic polymer latex such as acrylate or methacrylate polymer or copolymer, ethylene-vinyl acetate An acetic acid polymer latex such as a copolymer and a synthetic adhesive such as polyvinyl alcohol are appropriately selected, and one or more kinds are used for the present invention.

The amount of the adhesive used is 8 to 30 per pigment weight.
% By weight, preferably 10 to 20% by weight. If the amount of the adhesive used is less than 8% by weight, the strength of the coated surface becomes weak, and
If the content exceeds 0% by weight, the cost increases, which is not suitable for the present invention.

In preparing the coating solution, various auxiliaries such as a dispersant, a flow modifier, an antifoaming agent, and a coloring agent, which are blended in a general coating solution for a coated paper, have desired characteristics. It is appropriately selected and used as needed.

The solid content of the coating solution is 45 to 75% by weight.
It is preferably about 55 to 70% by weight in consideration of the drying load and the operability affected by the viscosity of the coating liquid.
It is.

The aqueous coating solution prepared as described above is prepared by using a pulp selected from softwood bleached kraft pulp, hardwood bleached kraft pulp, deinked waste paper pulp, mechanical pulp and the like on a normal paper machine. Using the acid paper or neutral paper made as a base paper, 10-30 g /
m ² , preferably 15 to 25 g / m ² . The base paper used in the present invention may have a basis weight of 50 to 400 g / m ² , and may be a single-layer paper or a multi-layer paper.

As described above, the aqueous coating liquid may be applied directly to the base paper, or may be applied to the base paper in an amount of 3 to 15 g per side.
In a range of / m ^2, a two-layer coating, which is a so-called double coating, in which a coating liquid containing a pigment and an adhesive as main components is coated as an undercoat on a base paper coated, may be used.

In the present invention, the method of coating and drying is not particularly limited, and a blade coater, an air knife coater, a bar coater, a roll coater, a champlex coater, a size press used in general coated paper production. One or both sides of the paper are coated in a single layer or a multilayer by a coater, a gravure coater or the like, and dried by an optional drying equipment. In the case of double-sided coating or multi-layer coating, all coatings may be performed continuously using a single coater having two or more coating equipments. The winding and then the rest of the coating may be performed on the same or another coater. The final coated paper product is dried to a paper moisture content in the range of 3-8% by weight and wound on a reel.

The coated paper thus obtained is provided with a nip formed between a smooth metal finishing drum (hereinafter referred to as a chilled roll) of a finishing device and an elastic backing roll by a chilled roll having a smooth coated surface. It is passed so as to contact the surface, and this process is performed once for single-sided coating.
In the case of double-sided coating, this process is performed once each for both sides. Such a finishing treatment can be carried out twice or more per side, but an excessive treatment is not desirable because the rigidity of the coated paper decreases as the number of treatments increases. Such a treatment may be performed after the coated and dried coated paper is wound once, or may be performed before winding (immediately after drying).

The finishing apparatus has a nip width between the chilled roll and the elastic backing roll of 1 to 5 cm, preferably 1.5 to 4 cm, and a pressing pressure of 10 to 100 kg / cm.
² , preferably 20 to 80 kg / cm ² , and the surface temperature of the chilled roll is 100 to 190 ° C., preferably 120 to 17 ° C.
Adjusted to the range of 0 ° C.

When the nip width is less than 1 cm, the effect of exhibiting water resistance is not sufficient, or the water resistance tends to be uneven,
On the other hand, even if a nip width exceeding 5 cm is applied, the effect of exhibiting water resistance is flat, and in order to increase the nip width, the diameter of a chilled roll or an elastic backing roll must be extremely large or an elastic backing must be used. The hardness of the roll must be extremely low, making it impractical.

In order to measure the nip width, the back carbon paper is pressed between the nips to measure the coloring width of the carbon on the roll, or the pressure-sensitive coloring sheet is pressed between the nips to measure the developed width. Also, a method of measuring the width of a portion where the roughened surface is flattened by pressing the roughened aluminum foil between the nips is known, and these methods are appropriately selected and used in the present invention.

When the pressing pressure is less than 10 kg / cm ² , the effect of exhibiting water resistance is not sufficient, and when it exceeds 100 kg / cm ² , the rigidity of the obtained coated paper for printing tends to decrease. The pressing pressure is such that the nip linear pressure between the rolls indicated by the pressure gauge is PKg / cm, and the nip width at this time is N
cm, it can be calculated by P / NKg / cm ² .

If the surface temperature of the chilled roll is less than 100 ° C., the effect of exhibiting water resistance is not sufficient, and if it exceeds 190 ° C., an excessively glossy portion is unevenly formed on the surface of the coated paper,
In addition, since the "burn" phenomenon occurs and the whiteness is reduced, the value is lost as a coated paper for printing. The surface temperature of the chilled roll can be adjusted by any known method such as a method of passing high-temperature steam into the drum, a method of incorporating an electric heating element into the drum, and a contact or non-contact surface. With a thermometer, the surface temperature can be measured. It is known that the temperature of the chilled roll is lowered by 10 to 20 ° C. from the start of the operation of the finishing apparatus because heat is taken away by the paper during the processing of the paper. In this case, the temperature is adjusted by increasing the temperature.

The mechanism of how the action and effect obtained in the present invention is expressed is not clear so far, but can be considered as follows. That is, the wax emulsion blended in the coating layer is initially distributed in the coating layer in the form of fine particles like other pigment components, and the water resistance has not yet been sufficiently exhibited in this state. The coated film after coating is heated during drying. In this case, it is considered that water in the coated film is mainly evaporated and the wax fine particles are not sufficiently melted. However, by performing the finishing treatment of the present invention at this stage, the wax fine particles are completely melted and sufficiently penetrate into fine voids in the coating film. As a result, in the coating film of the coated paper for printing, Water is prevented from penetrating into the water and water resistance is fully exhibited. Therefore, in order to complete sufficient melting and infiltration of the wax fine particles, a nip width which is somewhat large as in the present invention,
Appropriate pressing pressure and the surface temperature of the chill roll are extremely important.

The coated paper thus obtained may be subjected to surface finishing using a super calender or the like in an on-machine or off-machine state, if necessary. Excessive processing that significantly impairs must of course be avoided.

In the present invention, a wax emulsion is added to the coating liquid, and in addition to this, a finish comprising a chilled roll and an elastic backing roll in which the coated paper has a surface temperature in a specific temperature range after the coating film is dried. By performing the treatment with a specific nip width and a specific nip pressing pressure using an apparatus, it is possible to obtain a coated paper having good water resistance and good rigidity.

[0043]

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples. In addition, parts or% shown in Examples and Comparative Examples
Represents the absolute dry weight part or the absolute dry weight%. All coating amounts are indicated by absolute dry weight.

Example 1 Kaolin (UW-90, manufactured by Engelhard, USA) 80% and light calcium carbonate (Tamapearl 123-SF, manufactured by Okutama Kogyo) 2
0.4 parts of sodium polyacrylate was added per 100 parts of the mixed pigment of 0%, and dispersed in water using a dellitter (manufactured by Serie) to prepare a pigment slurry having a solid content of 65%. Next, a coating liquid was prepared using the pigment slurry according to the following formulation.

Composition of Coating Solution Pigment 80% Latex (Asahi Kasei, L-1537) 13% Oxidized Starch (Oji Cornstarch, Ace A) 2% Wax Emulsion (Arakawa Chemical, emulsion sizing agent, SPW-116H) 5%

Per 100 parts of solid content of this coating solution, 0.5 part of calcium stearate as lubricant and 0.1 part of fluorescent dye were used.
2 parts, 0.2 parts of an antifoaming agent and water were sequentially added, and after sufficiently stirring and mixing, the pH was adjusted to alkaline with a 25% aqueous ammonia solution to obtain an aqueous coating solution having a solid content of 60%. .

This coating solution was used for hardwood bleached kraft pulp 9
Using a mixed pulp consisting of 0% and 10% softwood bleached kraft pulp, a basis weight of 110 g / m ² was formed by a normal paper machine.
Blade coater (Mitsubishi Heavy Industries) on one side of paper base
Then, 15 g / m ^{2 was} applied per one side, and then dried to 5.5% moisture using a hot air drier consisting of 4 sections (manufactured by Ishikawajima-Harima Heavy Industries, arch type hot air drier, drying length: 6 m each). The same coating and drying were performed on the opposite side of the coated paper after the coating on one side, to produce a coated paper having a basis weight of 140 g / m ² which was coated on both sides.

Two finishing units each comprising a chilled roll having a surface temperature of 140 ° C. and an elastic roll made of urethane resin (Shore D hardness, 61 degrees) are installed, and the dried double-side coated paper is applied to this finishing unit. Introduced, the front and back coating surfaces are each 1
The paper was passed through the chilled roll to finish it. At this time, the nip linear pressure was 120 kg / cm, the nip width was 3.0 cm, and the pressing pressure was 40 kg / cm ² .

The quality of the obtained coated paper was evaluated by the following test method. (1) Taber stiffness The longitudinal direction of the paper was measured by the method specified in JIS P8125. (2) Paper waist The end of the paper was pinched with a fingertip, and it was judged as follows and displayed as follows. ：: Crisp and hard feeling. Δ: Neither can be said. □: It feels soft. ○ △, △ □ indicate the middle of each.

(3) Degree of Cobb Size Measured by the method specified in JIS P 8140.
The contact time between the test piece and water was 30 seconds. (4) Cut the coated paper into a size of 15 cm x 15 cm, apply a vinyl acetate water-based emulsion type adhesive (manufactured by Siden Chemical Co., Sibinol GH-451) on one side with a brush,
After 0 seconds, the surface on the opposite side was visually judged for the unevenness, and displayed as follows. ：: There is no unevenness. Δ: There is slight unevenness. □: Large unevenness. ○ △, △ □ indicate the middle of each.

Example 2 84.2% of the same pigment slurry as in Example 1 was used, the wax emulsion (SPW-116H) was 0.8%, the surface temperature of the chill roll was 180 ° C., and the hardness of the elastic roll was 50 Shore D hardness. A coated paper was manufactured in the same manner as in Example 1 except that the degree was changed. The nip linear pressure at the finishing device is 65 kg / cm, the nip width is 4.5 cm, and the pressing pressure is 14.4 kg / cm.
^{And 2} . The quality of the obtained coated paper was evaluated in the same manner as in Example 1.

Example 3 The same pigment slurry as in Example 1 was used in an amount of 77.5%, a wax emulsion (SPW-116H) was used in an amount of 7.5%, the surface temperature of a chill roll was 110 ° C., and the hardness of an elastic roll was a Shore D hardness of 78. A coated paper was manufactured in the same manner as in Example 1 except that the degree was changed. The nip linear pressure at the finishing device is 135 kg / cm,
Nip width is 1.4cm and pressing pressure is 96.4Kg / c
It was m ^2. The quality of the obtained coated paper was evaluated in the same manner as in Example 1.

Example 4 A coated paper was produced in the same manner as in Example 1 except that the wax emulsion was replaced with a paraffin wax emulsion (manufactured by Chukyo Yushi, Hydrin D-338), and the quality was evaluated.

Example 5 A coated paper was produced in the same manner as in Example 1 except that the wax emulsion was replaced by a carnauba wax emulsion (manufactured by Kyo Chemicals, KW-578), and the quality of the coated paper was evaluated.

Example 6 A coated paper was produced in the same manner as in Example 1 except that the wax emulsion was replaced with a polyethylene wax emulsion (manufactured by San Nopco, OJY-1), and the quality of the coated paper was evaluated.

Example 7 A known three-layer papermaking machine using the same papermaking raw material as in Example 1 was used. The middle layer was 100 g / m ² , and both outer layers were 50 g / m2.
m ² , a paper substrate having a total of 200 g / m ² was prepared. Coated paper was manufactured using this in the same manner as in Example 1, and the quality was evaluated.

Example 8 The same base paper as in Example 7 was coated on both sides with a coating solution for undercoating shown below at a rate of 7 g / m ² per side, and dried to produce a paper base material.

Composition of Undercoat Coating Solution Kaolin (UW-90) 24% Heavy calcium carbonate (manufactured by our company, particle size 0.5 to 4 μm) 60% Starch oxide (Ace A) 2% Latex (L-1537) 14%

To the above composition, 0.3 part of sodium polyacrylate as a dispersant, 0.5 part of calcium stearate as a lubricant and 0.5 part of water were added in order to 100 parts of the pigment, and the mixture was mixed well and dispersed. The pH was adjusted to alkaline with the solution. The solid concentration was 60%. The same coating liquid composition as in Example 1 was further coated on the paper base material obtained as described above, followed by drying and finishing,
The quality of the obtained coated paper was evaluated.

Comparative Example 1 A coated paper was produced in the same manner as in Example 1 except that 84.8% of the same pigment slurry as in Example 1 was used and 0.2% of the wax emulsion was used. The paper quality was evaluated.

Comparative Example 2 A coated paper was produced in the same manner as in Example 1 except that the pigment slurry was 76% and the wax emulsion was 9%, and the quality of the obtained coated paper was evaluated. did.

Comparative Example 3 The elastic roll of the finishing device had a Shore D hardness of 90 degrees.
Further, the nip linear pressure is 70 kg / cm, and the nip width is 0.8 c.
m, and a coated paper was manufactured in the same manner as in Example 1 except that the pressing pressure was 87.5 kg / cm ^2, and the quality was evaluated.

Comparative Example 4 A nip linear pressure of 35 kg / cm, a nip width of 3.8 cm,
A coated paper was manufactured in the same manner as in Example 2 except that the pressing pressure was changed to 9.2 kg / cm ^2, and the quality was evaluated.

Comparative Example 5 A nip linear pressure of 200 kg / cm and a nip width of 1.9 c
m, a coated paper was produced in the same manner as in Example 3 except that the pressing pressure was set to 105.3 kg / cm ^2, and the quality was evaluated.

Comparative Example 6 A coated paper was produced in the same manner as in Example 1 except that the surface temperature of the chilled roll was 95 ° C., and the quality was evaluated.

Comparative Example 7 Example 1 was repeated except that the surface temperature of the chilled roll was 195 ° C.
A coated paper was manufactured in the same manner as described above, and the quality was evaluated.

Results obtained in Examples 1 to 8 and Comparative Example 1
Table 1 shows the results obtained in Nos. 1 to 7.

[0068]

[Table 1]

As can be seen from Table 1, according to the present invention,
Coating paper for printing having high rigidity, stiffness, and excellent water resistance can be produced (Examples 1 to 8), whereas when the content of the wax emulsion in the coating liquid is low, the water resistance is poor. (Comparative Example 1) When the content of the wax emulsion is high, the water resistance is excellent, but the stiffness, that is, the stiffness of the paper decreases (Comparative Example 2).
Not practical. On the other hand, even if the content of the wax emulsion is appropriate and the elastic roll has a high hardness even when a proper roll pressing pressure is used in the finishing apparatus, the coated paper obtained is inferior in water resistance because the nip width is small ( In Comparative Example 3), if the pressing pressure is further reduced, the stiffness of the coated paper increases even if the other conditions are appropriate, and the coated paper becomes firm, but is similarly poor in water resistance and unsuitable for use (Comparative Example 4). If the pressing pressure in the finishing device is high, the coated paper loses its stiffness (Comparative Example 5), and if the surface temperature of the chilled roll is low, the water resistance is inferior (Comparative Example 6). (See Comparative Example 7), all of which are not suitable for practical use.

[0070]

According to the present invention, it is possible to provide a coated printing paper having high rigidity, stiffness and excellent water resistance.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kimifumi Kusumi 373 Yoshioka, Yonago, Yonago, Tottori Prefecture Examiner at Yonago Mill, Yonago Mill Co., Ltd. Ruka Fuchino (56) References JP-A-53-41511 (JP, A) (JP) B-111 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) D21H 19/44 D21H 19/18

Claims (1)

(57) [Claims] 1. A coating liquid composition comprising a pigment, an adhesive and an auxiliary agent is coated on a paper substrate, and the formed coating layer is dried, and then a smooth metal finishing drum and an elastic backing are coated. In a method for producing a coated paper for printing which is finished by passing through a nip between rolls, (1) a wax emulsion of 0.5 to 8% per solid content of the coating liquid is contained in the coating liquid composition. (2) the nip has a nip width of 1 to 5 cm and a pressing pressure of 10 to 100 kg / cm ² , and (3) the surface temperature of the metal finishing drum is 100 to 190 ° C. Manufacturing method of coated paper for printing.