JPH0625999A - Production of multilayer coated paper - Google Patents

Abstract

PURPOSE:To obtain a method for producing multilayer coated paper excellent in operability of a blade coater and simultaneously having high quality. CONSTITUTION:In producing multi-layer coated paper by applying a coating composition consisting essentially of a pigment and an adhesive to precoaed base paper previously providing a precoating composition consisting essentially of a pigment and an adhesive by a blade coater, drying the coated composition and then finishing the surface by a calender, a surface sizing agent is added to the precoating composition in a solid amount of 0.1-5wt.% based on the pigment so as to keep a dynamic wetting value after 1sec of primer coating raw paper to <=-0.05g.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a multi-layer coated paper, and more particularly to a method for producing a coated paper which has a high quality and is excellent in operability by specifying an undercoat base paper.

[0002]

2. Description of the Related Art In recent years, visualization of printed matter and color
With the trend toward higher quality and higher quality, there is an increasing demand for improvement in glossiness, luster and smoothness of the coated surface of the coated paper for printing. Therefore, various proposals have been made regarding the manufacturing process of the coated paper for printing. For example, as a coating method, a multi-layer coating method using a blade coater is used.
Finishing method using a high temperature calender of 0 ° C or higher
No. 4-125712, Japanese Patent Publication No. 49-21252, etc.) have been proposed.

Generally, it is known that the coated paper obtained by the multi-layer coating has higher smoothness, gloss, shine and the like than the coated paper obtained by the single layer coating. Also, smooth the undercoat by calendering it.
It is also generally known that when a smoothing treatment is performed by using a fine pigment as a pigment in the undercoat coating composition, finally a higher quality coated paper is obtained (WOCHENBLATT F
UR PAPIER FABRIKATION 10,1974, P353 ~ 362).

It has been proposed to use fine pigments such as satin white, ultrafine particle kaolin, and ultrafine particle calcium carbonate, or organic pigments as pigments for coating compositions for obtaining high-quality coated paper. Many high-concentration coating methods have been proposed in which the coating liquid concentration during blade coating is 65% by weight or more. However, in order to obtain a high-quality coated paper which is excellent in operation, there are still many problems to be considered.

That is, in the case of coating with a blade, a so-called staractite or brie in which a highly concentrated or semi-solidified coating liquid is deposited on the blade tip.
A phenomenon called ding may occur. this is,
Blade extension length, blade angle, etc.
It is considered that this is caused by the setting conditions of the coating, the dwell time from the application of the coating liquid to the scraping by the blade, and the fluidity and water retention of the coating liquid. TECHNOLOGY VOL33 NO.4 P.14 ~ 18 C
oating Conference 1989 P.59-63).

As a result, the above-mentioned staractite causes streaks and scratches, and when transferred to the paper surface, it becomes paper dust and the like, which causes many troubles in terms of operation and quality. In particular, when performing multi-layer coating, the surface of the undercoat layer tends to be inferior in water repellency compared to the surface of the base paper, and the frequency of occurrence of stalactite during coating of the overcoat layer is high, which deteriorates operability and quality. There is.

[0007]

DISCLOSURE OF THE INVENTION The present invention provides a method for producing a multi-layer coated paper having excellent operability of a blade coater and high quality.

[0008]

DISCLOSURE OF THE INVENTION The present invention relates to a base paper having a pigment and an adhesive as a main component, and a base paper having a base coating composition containing a pigment and an adhesive as a main component is previously provided on the base paper. In a method for producing a multi-layer coated paper in which a composition is coated and dried by a blade coater and then calendered, a surface sizing agent is added to the undercoat composition in a solid amount of 0.1 to a pigment. By adding 5% by weight, 1
The method for producing a multi-layer coated paper is characterized in that the dynamic wetting value after seconds is −0.05 g or less.

[0009]

The inventors of the present invention have conducted extensive studies on the factors causing the formation of the above-mentioned staractite in the blade coating and measures for preventing it. As a result, it was found that the staractite phenomenon that occurs when applying the coating liquid for the overcoat layer to the undercoat base paper is greatly related to the initial water repellency of the undercoat base paper, and the surface sizing agent is added to the undercoat coating composition. Add a specific amount of
Moreover, by adjusting the dynamic wetting value after 1 second of the undercoat base paper, which is dried by coating on both sides, to a certain value or less, the generation of staractite can be suppressed very efficiently, and the effect of multi-layer coating is sufficiently expressed. The inventors have found that a high quality coated paper can be obtained, and completed the present invention.

That is, when the undercoat base paper is coated with the coating liquid for the overcoat layer, it is metalized by a blade after the coating liquid is applied. However, when the undercoat base paper has a low initial water repellency. , The coating liquid is absorbed by the undercoat base paper, the concentration of the coating liquid increases sharply, and the fluidity of the coating liquid changes, so that the state of the coating liquid in the blade changes, and the stactite, a so-called solidified coating The phenomenon that a piece jumps out of the blade edge frequently occurs. In order to suppress such a staractite phenomenon, it is necessary to appropriately increase the initial water repellency of the base paper for undercoating and suppress rapid penetration of the coating liquid. Therefore, it has been found that the desired effect can be obtained by adding a specific amount of a surface sizing agent having a hydrophilic group and a hydrophobic group to the undercoat coating composition.

Here, the surface sizing agent is generally used for clear coating such as size press, and particularly starch,
It is used in combination with a water-soluble polymer such as polyvinyl alcohol to improve the size of paper.
Generally, the surface sizing agent is an olefin-polycarboxylic acid copolymer system, a styrene-acrylic acid copolymer system, a styrene-polycarboxylic acid copolymer system, a petroleum resin system, a rosin ester system, a styrene acrylic emulsion system, an acrylic acid copolymer system. System, acrylic emulsion system, wax system,
Examples include urethane-based, alkyl ketene dimer, fatty acid-based cation sizing agents, copolymer-based cation sizing agents, and petroleum resin-based cation sizing agents.

In the present invention, preferred surface sizing agents include olefin-polycarboxylic acid copolymer systems and styrene-acrylic acid copolymer systems. A more preferable surface sizing agent is an α-olefin-α type diisobutylene-maleic anhydride copolymer which exhibits anionic properties. Usually, since the coating composition is anionically charged, the surface sizing agent is preferably anionic in view of the stability of the coating composition.

Particularly preferable surface sizing agents are copolymers having a hydrophilic group and a hydrophobic group and exhibiting anionic property.

In this case, the hydrophilic group is bound to the water-soluble polymer substance and the hydrophilic pigment in the coating composition, while the hydrophobic group is easily oriented on the surface of the coating composition, so that the undercoating is easy. The surface of the base paper becomes water repellent. Among them, as the hydrophilic group, at least one kind is selected from unsaturated polycarboxylic acids and salts thereof, unsaturated polycarboxylic acid partial esterified products and salts thereof, and (meth) acrylic acid and salts thereof. On the other hand, as the hydrophobic group, styrenes, α-olefins,
One or more selected from diisobutylene and (meth) acrylic acid ester. The above-mentioned copolymer which is a combination of the hydrophilic group and the hydrophobic group is preferable from the viewpoint of imparting desired water repellency to the base paper for undercoating.

Examples of unsaturated polycarboxylic acids and salts thereof include maleic acid, fumaric acid, itaconic acid, citraconic acid and other acids, and anhydrides and salts thereof.
As the unsaturated polycarboxylic acid partial esterified product and its salt, the same components as the above unsaturated carboxylic acid are used,
As the one forming an ester, one having 4 to 24 carbon atoms is used.

Further, as styrenes, styrene and α
-Methylstyrene, etc., the α-olefins have 8 to 20 carbon atoms, and specific examples include 1-octene,
There are 1-nonene, 1-decene, 1-dodecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc., and diisobutylene contains at least α-type ester of acrylic acid ester. Those having 4 to 24 carbon atoms are used for forming.

The ratio of hydrophobic groups to hydrophilic groups is 7
0:30 to 30:70, preferably 40:60 to
It is 60:40. The molecular weight is 1,000 to 50,000, preferably 2,000 to 30,000. These ranges are appropriately determined depending on the physical properties of the surface sizing agent and the coating liquid using the surface sizing agent, and the water repellency of the base paper for undercoating.
The production of an anionic water-soluble polymer substance composed of a hydrophilic group and a hydrophobic group is described in JP-A-2-200896, JP-A-2-269895, JP-A-56-63098, etc. Can be used.

Further, the amount of the surface sizing agent added to the undercoat coating composition is 0.1 to 5% by weight, and more preferably 0.3 to 3% by weight, based on the pigment, as a solid amount. By the way,
If it is less than 0.1% by weight, the desired water repellency of the base paper for undercoating cannot be obtained at the time of coating, and stlactite is likely to be generated at the time of coating the top coating material with a blade. On the other hand, when it exceeds 5% by weight, the surface strength of the finally obtained coated paper is lowered, and problems such as picking are likely to occur during printing.

As a method of knowing the water repellency of the base paper for undercoating, generally, there is a Steckigt sizing degree or water absorption degree of Cobb. In these methods, the base paper for undercoating and the coating liquid are separated by blades. It was not possible to find water repellency in a short time to be metallized. As a result of earnest study,
The present inventors have found that the value obtained by using the dynamic wettability tester has an extremely excellent correlation with the water repellency desired in the present invention.

That is, the base paper for undercoat of the present invention is obtained by adding a specific amount of a surface sizing agent to the composition for undercoat to determine the dynamic wetting value and preparing the composition. Here, the dynamic wettability value of the undercoat base paper represents a change in the magnitude of the adhesive force with respect to water over time as a measure of wettability, and in the present invention, the wettability is measured by a dynamic wettability tester (WET-300.
It is a test value performed by using 0 / Resc Co., Ltd. Specifically, the value obtained by measuring the size of time wetting (adhesive force) when a 3 × 5 cm test piece is immersed in a depth of 12 mm in water for 10 seconds at a speed of 16 mm / sec, the value obtained (Hereinafter, referred to as dynamic wetting value) indicates that the larger the absolute value of the negative value is, the harder the wetting is, and the larger the positive value is, the easier the wetting is.

As a result of further research on the dynamic wettability value, it was found that the value 1 second after immersion in water can be an extremely effective index value for obtaining the desired effect in the present invention. In particular, by combining with a specific amount of the above-mentioned surface sizing agent to obtain a desired dynamic wetting value, it is possible to extremely efficiently suppress stlactite when coating the coating liquid with a blade on the basecoat paper. understood. That is, in the present invention, the dynamic wetting value of the undercoat base paper is specified to be -0.05 g or less. Incidentally, when the dynamic wetting value exceeds -0.05 g, the base coating liquid is easily absorbed in the base coating paper, the concentration of the coating liquid increases, and the fluidity of the coating liquid changes. Therefore, the state of the coating liquid on the blade changes,
The frequency of occurrence of staractite becomes high and the operability of the coater becomes unstable.

The coating composition for undercoat base paper of the present invention comprises a pigment, an adhesive and various auxiliaries in addition to the surface sizing agent.
As the pigment, at least one selected from clay, kaolin, aluminum hydroxide, calcium carbonate, titanium dioxide, barium sulfate, zinc oxide, calcium sulfate, talc, satin white, calcined kaolin, various white carbons, organic pigments, etc. is appropriately selected. used.

Examples of the adhesive include proteins such as casein, soybean protein and synthetic protein; conjugated diene polymer latex such as styrene-butadiene copolymer, polymer or copolymer of acrylic acid ester and / or methacrylic acid ester. Acrylic polymer latex such as coalesce, vinyl polymer latex such as ethylene-vinyl acetate copolymer; or alkali solubility of these various polymer latex modified with functional group-containing monomer such as carboxyl group Alternatively, alkali-insoluble polymer latex; synthetic resin adhesives such as polyvinyl alcohol and melamine resin; positive starch,
At least one of ordinary adhesives for coated paper such as starches such as oxidized starch; cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose is appropriately selected and used. Generally, the adhesive is 5 to 50 with respect to the pigment.
%, More preferably in the range of about 10 to 30% by weight.

In addition, various auxiliary agents such as a water-proofing agent, an antifoaming agent, a release agent, and a flow modifier are appropriately blended in the coating composition, if necessary, to solidify the coating layer. As an accelerating agent,
For example, 0.1 to 10% by weight of amine, amide, polyacrylamine, etc. or salt of polyvalent metal such as zinc, aluminum, magnesium, calcium, barium, etc. with respect to the pigment.
It can be added to some extent.

The undercoat coating composition obtained under the above-mentioned conditions is a blade coater, an air knife coater, a roll coater, a reverse roll coater, a bar coater, a curtain coater, a die slot coater used in the production of general coated paper. , A gravure coater, a chanplex coater, a size press coater, etc. are used to coat the base paper in one layer or two or more layers by an on-machine or off-machine coater.

At that time, the solid content concentration of the coating composition is generally about 40 to 75% by weight, but the range of 45 to 70% by weight is preferable in consideration of operability and the like. When the coating composition is coated on the base paper, the coating amount is 3 to 25 g / m per side in consideration of the smoothness of the obtained base coating base paper, the occurrence of strikes due to the top coating composition, and the like. It is adjusted in the range of about ² .

As a method for drying the wet coating layer, various methods such as steam heating, hot air heating, gas heater heating, electric heater heating, infrared heater heating, high frequency heating, laser heating and electron beam heating are adopted. However, it is not particularly limited. This undercoat base paper can be subjected to a calendering process on machine or off machine. For example, a machine calender, a super calender, a soft compact calender, a gloss calender or the like is used.

The base coating composition thus obtained is coated with the coating composition for top coating. In addition, the top coating composition usually comprises a pigment, an adhesive and an auxiliary agent as in the case of the under coating composition. In that case, as the pigment, the adhesive and the auxiliary, those similar to the pigment, the adhesive and the auxiliary used in the undercoat coating composition are appropriately combined and used. In particular, when a coating composition containing satin white or an organic pigment is coated on a base paper for undercoating, excellent smoothness, gloss and shine are exhibited, which is preferable as a coated paper for high-grade printing.

The adhesive in the overcoat coating composition is 5 to 50% by weight, more preferably 10 to 30% by weight of the pigment.
About wt% is added.

The topcoat coating composition thus obtained is
When the undercoat base paper is applied by an on-machine or off-machine coater by an applicator that weighs and smoothes the base coat after excessively applying it to the base coat with a blade coater. After coating and drying the undercoat coating composition, the coating composition for topcoating may be continuously coated, or after coating and drying the undercoating coating composition, it is temporarily wound and then coated for topcoating. The composition may be coated.

The solid content concentration of the coating composition at that time is generally about 40 to 75% by weight, but it is preferably in the range of 45 to 70% by weight in consideration of operability and the like. In addition, the coating composition for topcoating on the undercoat raw paper is generally about 3 to 50 g / m ² on a dry weight basis, but it is 8 to 25 g / m ² in consideration of the white paper quality of the resulting coated paper, printability, and the like. It is desirable to adjust in the range of about m ² .

As a method for drying the wet coating layer for top coating, the same drying method as that for drying the composition for undercoat coating is appropriately used and is not particularly limited.

Examples of calender finishing methods include, for example, super calender, gloss calender, soft calender, soft compact calender (Paper and Pulp Technology Times / August 1987, pages 31-36;
October 1991, 42-47; PPI / November 1987, 45-47; WFP / 1985, 22,
Pp. 873-877) is applied on-machine or off-machine.

The surface temperature of the metal roll is about 20 to 3
Used at 50 ° C. When the temperature is lower than 20 ° C, the smoothing improving effect is insufficient. On the other hand, when the temperature is higher than 350 ° C, the microscopic pores of the coating layer are crushed, and the ink absorbency at the time of printing the coated paper is deteriorated. This makes it difficult to perform stable offset printing operation, which is not preferable.

The base paper in the present invention is, for example, 30 square meters.
About 400 g / m ² can be used. This base paper is
It can be obtained by adding a filler, a sizing agent, a paper strength enhancer, a retention aid, various auxiliaries and the like to pulp. The pulp is appropriately selected and used from chemical pulp and mechanical pulp made from wood fiber and plant fiber such as hemp, recycled pulp obtained from chemical pulp and mechanical pulp, synthetic pulp, inorganic fiber and the like.

As the filler, known and publicly-used materials generally used in the paper manufacturing industry are appropriately used. Furthermore, the pigments contained in used paper, broke, etc. can be recycled.

In addition to pulp fiber and filler in the paper,
Within the range that does not impair the desired effects of the present invention, various conventionally used anionic, nonionic, cationic or amphoteric retention improvers, drainage improvers, paper strength improvers and internal sizing agents. An internal additive for papermaking such as is used as necessary. Further, a papermaking internal additive such as a dye, a fluorescent whitening agent, a pH adjusting agent, a defoaming agent, a pitch control agent, and a slime control agent are appropriately added as necessary.

In the papermaking method, for example, the papermaking PH is 4
It is about 5 to about 5, or a so-called neutral paper, which is mainly made of an alkaline filler such as calcium carbonate and has a pH PH of about 6, which is weakly acidic to about 9 and is alkaline, is appropriately selected. Further, as the paper machine, a Fourdrinier paper machine, a twin wire machine, a cylinder paper machine, a Yankee paper machine or the like is appropriately used.

In the present invention, the effect desired in the present invention is further improved by specifying the dynamic wetting value of the base paper before applying the undercoat coating composition. In that case, the dynamic wetting value of the base paper after 1 second is -0.30 to +0.
It is desirable to specify 20 g. By the way, +0.20
If it exceeds g, water easily penetrates into the base paper, and as a result, the water repellency of the base paper for undercoating decreases, and stlactite is likely to occur when the overcoating coating composition is applied with a blade. On the other hand, if the amount is less than -0.30 g, the compatibility between the base paper and the undercoat coating layer is reduced, and the surface strength is likely to be reduced. The preparation of the dynamic wetting value of the base paper is based on the pulp composition,
It can be carried out by appropriately combining beating conditions, types and amounts of fillers, paper strength agents, internally added sizing agents, PH, surface sizing agents, surface treatment agents, and drying conditions.

[0040]

The present invention will be described in more detail with reference to the following examples, but the scope of the invention is not limited thereto. In the examples, “parts” and “%” represent “parts by weight” and “% by weight”, respectively, unless otherwise specified.

Example 1 <Preparation of base paper> LBKP (csf 400 ml) 100 parts of pulp slurry, light calcium carbonate (Tamapearl TP-121 / Okutama Kogyo) and talc (NK) as fillers.
Talc / Chuo Kaolin Co.) 1: 1 has 1 paper ash
0.5% of aluminum sulfate,
0.5 parts of cationic starch (BMB-190 / manufactured by Nissan Eka Nobel), alkyl ketene dimer (HACON 60
1 / Dick Hercules) and 0.05 parts colloidal silica (BMA-0 / Nissan Eka Nobel).
A paper stock was prepared by adding 1 part, and then papermaking was carried out by a twin wire papermaking machine to obtain a raw paper. This raw paper was mixed with 5% of oxidized starch (ACE A / manufactured by Oji Cornstarch Co., Ltd.) by a size press machine and a surface sizing agent [α-olefin-α type diisobutylene-maleic anhydride-maleic anhydride partial esterified salt Polymer (Polymaron 1329K / anionic / manufactured by Arakawa Chemical Industry Co., Ltd.)] A 0.05% aqueous solution was subjected to size press treatment so as to be 50 cc / m ² on both sides, and after drying, the tsubo was 70 g / m 2. I got ² base papers. The dynamic wetting value of the base paper at this time was -0.02 g.

<Preparation of Undercoat Coating Composition> An aqueous dispersion of a pigment comprising 80 parts of ground calcium carbonate (Softon 1800 / manufactured by Bihoku Powder Co., Ltd.) and 20 parts of kaolin (manufactured by HT / EMC) as a dispersant. , 0.3 parts of sodium polyacrylate were added and dispersed using a Choles disperser to obtain a solid concentration of 6
An 8% pigment slurry was prepared. 10 parts of oxidized starch (Ace A / manufactured by Oji Corn Starch) (solid content), styrene-butadiene copolymer latex (JSR0696 / manufactured by Japan Synthetic Rubber Co., Ltd.) (solid content) 5
Parts and surface sizing agent [.alpha.-olefin-.alpha. Type diisobutylene-maleic anhydride copolymer (Hamacoat AK-
400 / anionic / manufactured by Misawa Ceramic Chemical Co., Ltd.)] (solid content), and water was further added to obtain a coating composition having a solid content concentration of 60%.

<Preparation of Coating Composition for Topcoat> An aqueous dispersion of a pigment comprising 80 parts of kaolin (UW-90 / EMC) and 20 parts of light calcium carbonate (Tamapearl TP-123 / Okutama Kogyo). As a dispersant, 0.2 part of sodium polyacrylate was added and dispersed using a Choles disperser to prepare a pigment slurry having a solid content concentration of 68%. 3 parts of oxidized starch (Ace A / manufactured by Oji Corn Starch) (solid content) and styrene-butadiene copolymer latex (JSR0696 / manufactured by Japan Synthetic Rubber Co., Ltd.) were added to the pigment slurry.
(Solid content) 10 parts was added, and further water was added to obtain a coating composition having a solid content concentration of 60%.

<Preparation of Undercoat Base Paper> The above basecoat composition was applied on both sides of a base paper having a basis weight of 70 g / m ^{2 by} a blade coater so that the dry weight per side was 10 g / m ² , and then dried. Then, an undercoat base paper was obtained. Table 1 shows the measurement results of the dynamic wetting value of the undercoat base paper.

<Manufacture of Multi-Layer Coated Paper> The undercoat base paper thus obtained is coated with the above-mentioned coating composition for top coating on both sides by a blade coater so that the dry weight per side is 10 g / m ² . The paper was dried so that the water content was 6.0%. Then, super calendering was performed under the conditions of 60 ° C., 11 nip, and linear pressure of 200 kg / cm to obtain a multi-layer coated paper. The occurrence of structite during blade coating of the multi-layer coated paper and the surface strength of the obtained coated paper were measured, and the results are shown in Table 1. The measurement items and evaluation criteria are as follows.

<Measurement of dynamic wetting value> Dynamic wetting tester (W
ET-3000 / manufactured by Resca Co., Ltd.), a 3 × 5 cm test piece was dipped at a depth of 12 mm in water for 10 seconds at a speed of 16 mm / second, and the wetting value was measured 1 second after the immersion. .

<Status of Occurrence of Staractite> The status of occurrence of staractite in the blade coater was visually evaluated according to the following criteria. Evaluation Criteria ⊚: almost no staractite is generated. ○: Staractite is generated, but it does not affect the operation of the coater. Δ: Staractite is generated, which disturbs the operability of the coater. X: A large amount of staractite is generated, and the coater cannot operate.

<Surface Strength of Multi-layer Coated Paper> The surface strength of the multi-layer coated paper was printed by using an RI printer (manufactured by Akira Seisakusho) and visually determined. Evaluation criteria ◎… very strong ○… strong ×… weak

Example 2 Coating was carried out in the same manner as in Example 1 except that the surface sizing additive was changed from 0.1 part to 0.5 part in the preparation of the undercoat coating composition of Example 1. I got the paper. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Example 3 In the preparation of the undercoating composition of Example 1, the pigment was ground calcium carbonate (Softon 1800 / Bihoku Kouka Co., Ltd.).
50 parts, and 50 parts of kaolin (manufactured by HT / EMC Co., Ltd.), and the surface sizing agent is α-olefin-α type diisobutylene-maleic anhydride-maleic anhydride partial esterified product salt copolymer (Polymaron 1329K / anionic / Arakawa Chemical Co., Ltd.), except that the addition amount was 3 parts,
A coated paper was obtained in the same manner as in Example 1. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Example 4 Coated paper was obtained in the same manner as in Example 3 except that the amount of the surface sizing agent added to the undercoat coating composition was changed from 3 parts to 5 parts. It was Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Example 5 In the preparation of the primer coating composition of Example 1, the surface sizing agent was a styrene-acrylic acid copolymer (Harsize KN).
-500 / anionic / made by Harima Kasei Co., Ltd., and coated paper was obtained in the same manner as in Example 1 except that the addition amount was changed to 1 part. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Example 6 In the preparation of the undercoat coating composition of Example 1, the surface sizing agent was changed to a copolymer type cationic sizing agent (NPPS / manufactured by Arakawa Chemical Industry Co., Ltd.), and the addition amount was 1 part. A coated paper was obtained in the same manner as in Example 1 except for the above. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Example 7 In preparation of base paper, LBKP (csf 400 ml) 90
Parts, BCTMP (csf250ml) 10 parts, pulp calcium slurry (Softon 1200 / Bihoku Powder Co., Ltd.) as a filler was added to a pulp slurry to make paper ash content 15%, and aluminum sulfate 0.5 parts , 1.0 part of amphoteric starch (Cato 3120 / Oji National Co., Ltd.),
After adjusting the stock with addition of 0.05 part of alkyl ketene dimer (Cyrene S-91 / manufactured by Kao Corporation) and 0.03 part of anionic polyacrylamide (arafix 504 / manufactured by Arakawa Chemical Industry Co., Ltd.), fourdrinier papermaking Paper was made with a machine to obtain raw paper.

The size press treatment was carried out in the same manner as in Example 1 to obtain a base paper having a basis weight of 70 g / m ² . The dynamic wetting value of the base paper at this time was -0.04 g.

In the preparation of the undercoat coating composition of Example 1, the surface sizing agent was changed to a styrene-acrylic copolymer emulsion (Hamacoat S-700 / anionic / Missawa Ceramic Chemical Co.), and the amount added A coated paper was obtained in the same manner as in Example 1 except that 1 part was added.
Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Example 8 A base paper having a basis weight of 70 g / m ² was obtained in the same manner as in Example 1 except that the size press treatment was not carried out in the preparation of the base paper. The dynamic wetting value of the base paper at this time was +0.10 g. In the preparation of the basecoat composition of Example 1,
A coated paper was obtained in the same manner as in Example 1 except that 1 part of the sizing agent used in Example 3 was added. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Example 9 In the preparation of base paper, LBKP (csf 400 ml) 100
Talc (NK talc /
Central Kaolin Co., Ltd.) was added so that the paper ash content was 5%, and further 1.5 parts of reinforced rosin (Size Pine E / Arakawa Chemical Industry Co., Ltd.) as an internally added sizing agent, 3.0 parts of aluminum sulfate, 0.5 parts of cationic starch (BMB-190 / manufactured by Nissan Eka Nobel) and colloidal silica (BM
0.1 part (A-0 / Nissan Eka Nobel) was added to adjust the stock, and then papermaking was performed with a Fourdrinier paper machine to obtain a raw paper.

In the size press process, the same as in Example 1 was used.
The concentration of the used surface sizing agent is 0.05% to 0.20%
The same method as in Example 1 except that the weight was changed to 70 g
/ M ²I got the base paper. Dynamic wetting value of base paper is -0.20g
Met. Example 1 Preparation Odor of Undercoat Coating Composition
A coated paper was obtained in the same manner as in Example 8. Example 1
The same evaluation was performed, and the results are shown in Table 1.

Comparative Example 1 A coated paper was obtained in the same manner as in Example 1 except that the surface sizing agent was not used in the preparation of the undercoat coating composition of Example 1. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 2 In the preparation of the basecoat composition of Example 1, Example 1
The amount of oxidized starch (Ace A / manufactured by Oji Corn Starch) (solid content) added to the pigment slurry in 10 to 3 parts
A coated paper was obtained in the same manner as in Example 1 except that the content was changed to 0 part. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.
It was shown to.

Comparative Example 3 In the preparation of the undercoat coating composition of Example 1, zirconium carbonate (Baycoat 20 / manufactured by Nippon Light Metal Company) was added to the pigment slurry of Example 1 without using a surface sizing agent.
A coated paper was obtained in the same manner as in Example 1 except that part of the paper was added. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 4 A coated paper was prepared in the same manner as in Example 3 except that the amount of the surface sizing agent added to the undercoat coating composition was changed from 3 parts to 0.05 part. Obtained. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 5 In Example 3, the surface sizing agent added to the undercoat coating composition was an acrylic copolymer emulsion (Harsize K).
N700 / anionic / made by Harima Kasei Co., Ltd.), and coated paper was obtained in the same manner as in Example 3 except that the addition amount was 0.1 part. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 6 A coated paper was prepared in the same manner as in Example 1 except that the amount of the surface sizing agent added to the undercoat coating composition was changed from 0.1 part to 7 parts. Obtained. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

[0066]

[Table 1]

[0067]

EFFECT OF THE INVENTION The multilayer coated paper obtained by the method of the present invention is excellent in quality with less generation of stalactite.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical display location D21H 19/36 23/34 7199-3B D21H 5/00 Z (72) Inventor Sasakuri Nobuyasu Hyogo 4-3-1, Jokoji, Amagasaki City Kanzaki Paper Manufacturing Co., Ltd. Kanzaki Mill

Claims (4)

[Claims] 1. A coating composition containing a pigment and an adhesive as a main component is coated on an undercoat base paper on which an undercoat coating composition containing a pigment and an adhesive as a main component is provided in advance. In the method for producing a multi-layer coated paper, which is finished by calendering after being coated and dried by the method described above, a surface sizing agent is added to the undercoat coating composition in an amount of 0.1 to 5% by weight based on the pigment to give an undercoat. Dynamic wetting value after 1 second of base paper is -0.05g
A method for producing a multi-layer coated paper, comprising: 2. The surface sizing agent is at least one selected from unsaturated polycarboxylic acids and salts thereof, unsaturated polycarboxylic acid partial esterified products and salts thereof, (meth) acrylic acid and salts thereof, and α -Olefins, styrenes,
The method for producing a multi-layer coated paper according to claim 1, which is a copolymer with diisobutylene and at least one selected from (meth) acrylic acid ester compounds. 3. The method for producing a multi-layer coated paper according to claim 2, wherein the copolymer is a water-soluble substance having an anionic property. 4. A base paper 1 before smearing a base coating composition
The method for producing a multi-layer coated paper according to claim 1, wherein the dynamic wetting value after seconds is −0.30 to +0.20 g.