JPH04343794A - Production of coated paper - Google Patents

Abstract

PURPOSE:To produce coated paper capable of imparting excellent printability and printing effects. CONSTITUTION:Base paper is coated with an anionic coating composition consisting essentially of a pigment and a water-based binder to produce coated paper. In the process, the raw paper for coating is precoated with a cationic polymer. The coated paper thus produced is excellent in water resistance, ink receptivity, ink setting properties and blister resistance and whiteness and opacity are also improved.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a method for producing coated paper by coating coated base paper with an anionic coating composition mainly consisting of a pigment and an aqueous binder. The present invention relates to a method for producing coated paper having improved qualities, such as providing excellent printability and printing effects.

0002

[Prior Art] Coated paper, which is made by coating base paper with an anionic coating composition mainly consisting of pigments and an aqueous binder, is used for commercial printed matter, magazines, and books due to its excellent printing effects. It is widely used. However, efforts are still being made to improve the quality of these coated papers as quality requirements become more sophisticated and diversified, and printing speeds increase. Particularly in offset printing, which accounts for the majority of printing methods, improvements and improvements in ink receptivity and wet pick strength under the influence of dampening water, as well as blister resistance in rotary printing, are important issues in the industry. It has become a challenge.

[0003] Various methods have been proposed and efforts have been made to improve these problems, but in combination with increasing quality requirements, their effects are not always satisfactory, and there are still some problems. Some had serious shortcomings.

[0004] For example, the quality of coated paper can be greatly changed by adjusting the type, composition, or blend of pigments and aqueous binders; however, improvement in one property is often accompanied by a decrease in another property. However, there are limits to the improvements made by such methods. On the other hand, for example, JP-A-1-97296
No. Publication, and H. G. Gatterer et al., P.T.
A cationic coating composition was proposed in the 1983 Coating Seminar presentation paper (Japanese translation is published in "PTS 1983 Coating Seminar", published by Uni Publishing Co., Ltd., pages 17-32). Furthermore, although a coating composition containing a cationic resin has been proposed in JP-A-2-84598, it is still not widely put into practical use due to problems with the preparation method of the coating composition and coating suitability. It has not yet reached the point where it has been standardized. It is also known to use water resistance agents and printability improvers such as polyamide polyurea resins to improve water resistance, ink receptivity,
They are used in the industry because they are effective in improving blister resistance, but the degree of improvement is no longer necessarily sufficient as quality requirements have increased in recent years.

[0005]

[Problems to be Solved by the Invention] The purpose of the present invention is to solve the above-mentioned problems, that is, to coat base paper with an anionic coating composition mainly consisting of a pigment and an aqueous binder. An object of the present invention is to provide a method for producing coated paper that can highly improve printability and printing effects such as water resistance, ink receptivity, and blister resistance.

[0006]

[Means for Solving the Problems] As a result of extensive research, the present inventors have found that coated paper is manufactured by coating coated base paper with an anionic coating composition mainly consisting of a pigment and an aqueous binder. In this process, it was discovered that by coating the coated base paper with a cationic polymer in advance, the printability and printing effect of the resulting coated paper could be significantly improved, leading to the present invention. That is, the present invention provides a method for producing coated paper, which comprises coating a cationic polymer on a coated base paper, and coating thereon an anionic coating composition mainly consisting of a pigment and an aqueous binder. This is what we provide.

[0007] The present invention is characterized in that the base paper for coating is coated with a cationic polymer in advance, and the base paper coated with the cationic polymer is coated with an anionic coating mainly consisting of a pigment and an aqueous binder. It is thought that when the coating composition is applied, the affinity between the cationic polymer and the anionic coating composition promotes color set, improves coverage, and makes the coating layer porous. , the resulting coated paper has excellent water resistance, ink receptivity, blister resistance,
Remarkable improvements in ink setting properties, etc. are observed. The present invention will be explained in more detail below.

The cationic polymer used in the present invention is:
It refers to a polymer whose main body dissociates into cations in an aqueous medium, and typical cationic groups include primary, secondary, and tertiary amino groups, and quaternary ammonium salts. Any such cationic polymer can be used, and its type is not particularly limited, but examples of cationic polymers preferably used in the present invention include the following.

a) Polyalkylene polyamide obtained by dehydration condensation of polyalkylene polyamine and dibasic carboxylic acid; b) Polyalkylene polyurea obtained by deammonization condensation of polyalkylene polyamine and urea; c) Polyalkylene polyurea obtained by dehydration condensation of polyalkylene polyamide and urea. Ammonia-condensed polyamide polyurea; d) A polyaminoepoxy resin obtained by reacting an amino group-containing compound with epihalohydrin; e) A reaction product obtained by further reacting any of the polymers a) to d) with an aldehyde; f) A reaction product obtained by reacting any of the above polymers a) to d) with an alkylating agent; g) a ring-opening polymer of ethyleneimine; h) a cationic vinyl monomer polymerized alone or other copolymerization i) a homopolymer of an N-vinylamide monomer or a hydrolyzate of a copolymer with other copolymerizable monomers; j) a polymer having active hydrogen, ammonia, primary A Mannich reaction product in which an amine or a secondary amine is reacted with formaldehyde; k) A reaction product in which a polymer having active hydrogen is reacted with a cationizing agent; l) A product in which a polymer having active hydrogen is reacted with ammonia or amines and epihalohydrin Reactant; m
) Chitosan obtained by hydrolyzing chitin; n) A block copolymer obtained by reacting a polymer having active hydrogen with any of the polymers a) to m) above using a crosslinking agent such as aldehyde, epihalohydrin, or polyisocyanate. .

Specific examples of raw material compounds used in producing these various cationic polymers are listed below.

The polyalkylene polyamine used in a) and b) above is a compound in which two primary amino groups and at least one secondary amino group are bonded via an alkylene, and includes diethylenetriamine, triethylenetetramine, and tetramine. Examples include ethylenepentamine and iminobispropylamine.

The dibasic carboxylic acid used in a) above is a compound having two carboxyl groups, and includes aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, sebacic acid, maleic acid, and fumaric acid. Examples include aromatic dicarboxylic acids such as isophthalic acid, terephthalic acid, and mixtures thereof.

Examples of the amino group-containing compound used in d) above include ammonia, various amines, polyalkylene polyamines, polyalkylene polyamides, polyalkylene polyureas, and polyamide polyureas.

[0014] Examples of the epihalohydrin used in d), l) and n) above include epichlorohydrin and epibromohydrin.

Examples of the aldehydes used in e) and n) above include alkyl aldehydes such as formaldehyde, acetaldehyde and propylaldehyde, and alkyl dialdehydes such as glyoxal, propane dial and butane dial.

The alkylating agent in f) above is as follows:
Various types can be used, such as: ■ General formula R1-X [wherein R1 is a lower alkyl group (e.g. carbon number 1-6
degree), lower alkenyl group (for example, about 2 to 6 carbon atoms)
, a benzyl group or a phenoxyethyl group, and X represents a halogen atom]. Preferred examples include methyl chloride, ethyl chloride, propyl chloride, allyl chloride, benzyl chloride, phenoxyethyl chloride, and bromides and iodides corresponding to these chlorides.

■ General formula (R2O)2SOv [In the formula, R2 is a lower alkyl group (for example, a carbon number of 1 to 6
degree), and v represents 1 or 2]. Preferred examples include dimethyl sulfite, diethyl sulfite, dimethyl sulfate, diethyl sulfate, and the like.

0018 ■ General formula

[0019]

[Chemical formula 1]

Ethylene oxide and its derivatives. Preferred examples include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, glycidol, and the like.

■ General formula

[0022]

[Case 2]

[In the formula, X represents a halogen atom, and w is 1
, 2 or 3]. Preferred examples include epichlorohydrin, epibromohydrin, and the like.

■ General formula HOCH2(CH2)wX [In the formula, X represents a halogen atom, and w is 1, 2 or 3
Monohalohydrin represented by ]. Preferred examples include ethylene chlorohydrin and ethylene bromohydrin.

0025 ■ General formula

[0026]

[Chemical formula 3]

A dihalohydrin represented by the formula [wherein, X represents a halogen atom, one of Y and Z represents a halogen atom, and the other represents a hydroxyl group]. A preferred example is 1,3-
Dichloro-2-propanol, 2,3-dichloro-1-
Examples include propanol.

The cationic vinyl monomers used in h) above include dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, dimethylaminoethyl (meth)acrylamide, dimethylaminopropyl (meth)acrylamide, and Examples include quaternized products of these, allylamine, diallylamine, triallylamine, vinylpyrrolidone, and diallyldimethylammonium salt.

Examples of the N-vinylamide monomer used in i) above include vinylformamide and vinylacetamide.

[0030] The active hydrogen-containing polymers used in j), k), l) and n) include starches,
Examples include polyvinyl alcohol, polyacrylamide, proteins such as casein, and methylcellulose.

Examples of the cationizing agent used in the above k) include those represented by the following general formula in addition to ethyleneimine.

[0032]

[C4]

[In these formulas, Q represents a divalent aliphatic group or an aromatic group, R4 and R5 each independently represent a lower alkyl group (for example, about 1 to 6 carbon atoms),
R6 represents a hydrogen atom or a lower alkyl group (for example, about 1 to 6 carbon atoms), A- represents an anion such as a halide ion or a sulfate ion, and L represents a halogen atom, a sulfonic acid ester group, a sulfuric ester group, etc. ] represents the leaving group of

In the above formula, the divalent aliphatic group represented by Q includes, for example, alkylene having about 1 to 10 carbon atoms, and this alkylene may be branched and may have a substituent. may have. Examples of the substituent of alkylene include a hydroxyl group, an alkoxy group having about 1 to 6 carbon atoms, an alkanoyloxy group having about 1 to 6 total carbon atoms, and a halogen atom. Examples of the divalent aromatic group represented by Q include substituted or unsubstituted phenylene, and substituents for phenylene include those exemplified as the substituents for alkylene above, as well as carbon atoms of about 1 to 6. Examples include alkyl groups.

In the above formula, the sulfonic acid ester group represented by L is, for example, a methanesulfonic acid residue (CH3
SO2O−), ethanesulfonic acid residue (C2H5 SO
2O-), benzenesulfonic acid residue (C6H5 SO2
O-), toluenesulfonic acid residue (CH3 C6H4
Sulfuric acid ester groups include ester groups of alkyl or arylsulfonic acids such as SO2O-), and examples of sulfuric acid ester groups include sulfuric acid residues (HOSO2O-), methyl sulfate residues (CH3 OSO2O-), ethyl sulfate residues, etc. (
C2H5 OSO2O-), phenyl sulfate residue (C6H
Examples include ester groups of alkyl or aryl sulfates such as 5 OSO2O-).

Among the various cationic polymers exemplified above, those having a colloidal equivalent value of 1 mg equivalent/g or more at pH 3 are preferable, and those having a colloid equivalent value of 2 mg equivalent/g or more are more preferable. . In particular, a 50% by weight aqueous solution having a viscosity of 10 cps or more at 25° C. is preferably used.

[0037] In addition to cationic polymers, polyvalent metal salts such as sulfates and chlorides of aluminum, calcium, and magnesium are also considered to interact with the anionic coating composition targeted by the present invention. However, these are not suitable because their effects cannot be obtained unless they are coated in large quantities on the coated base paper, and they also have a negative effect on the whiteness and shelf life of the coated base paper and coated paper. .

In the present invention, the cationic polymers described above can be used alone or in combination of two or more. In this case, there is no problem in using in combination starches with good compatibility, surface paper strength enhancers such as polyvinyl alcohols, polyacrylamides, various surface sizing agents, and the like. Further, optical brighteners, preservatives, antifoaming agents, lubricants, water repellents, water-resistant agents, colorants, and the like may be added as necessary while taking into account compatibility.

[0039] The cationic polymer is applied to a coating base paper using a size press coater, gate roll coater, machine calender, spray coater, etc., using a coating solution with an appropriate concentration taking into consideration the coating amount and suitability of the coating machine. Although it is coated on one or both sides of the film, it is particularly preferable to use an on-machine coater. Thereafter, by performing necessary drying, a coated base paper coated with a cationic polymer can be obtained. The amount of cationic polymer applied varies depending on the type of cationic polymer used, but it is approximately 0.
．． 01 to 2 g/m2/single side is preferred.

In the present invention, an anionic coating composition containing a pigment and an aqueous binder is applied to the coated base paper previously coated with a cationic polymer using a conventional method, that is, a size press coater or a gate roll. By applying the coating using a coater, air knife coater, bill blade coater, cast coater, blade coater, kiss roll coater, etc., and performing necessary drying and smoothing treatments, the desired printability and printing effect can be improved. coated paper can be produced.

[0041] There are no particular restrictions on the composition or concentration of the coating composition containing the pigment and the aqueous binder used here, the only condition being that it be anionic, but preferably per 100 parts by weight of the pigment. It contains about 5 to 50 parts by weight of an aqueous binder and has a solid content concentration of about 30 to 70% by weight.

[0042] The anionic coating composition referred to herein is the one most widely and commonly used for coating paper, and contains some form of anionic component such as a pigment, an aqueous binder, or a dispersant. It is sufficient if the composition as a whole exhibits anionic properties. For example, a white inorganic pigment or an organic synthetic white pigment is dispersed or slurried using an anionic dispersant such as sodium tripolyphosphate or a polyacrylate dispersant, and then a water-soluble binder and/or a water emulsifier is used. There are coating compositions containing a water-dispersed binder.

Among the pigments, examples of white inorganic pigments include kaolin, calcium carbonate, titanium oxide, aluminum hydroxide, and satin white, and examples of organic synthetic white pigments include polystyrene resins, urea/formaldehyde-based pigments, etc. Examples include resin. Among water-based binders, examples of water-soluble binders include oxidized starch, phosphoric ester starch, carboxymethyl cellulose,
Casein, polyvinyl alcohol, etc. may be mentioned, and examples of binders for water emulsions and water dispersion systems include styrene butadiene latex, vinyl acetate resin, ethylene vinyl acetate resin, and acrylic acid ester resin.

The pigments constituting the anionic coating composition can be used alone or in a mixture of two or more, and the aqueous binder can also be used alone,
Alternatively, two or more types can be used in combination. Furthermore, various auxiliary agents such as preservatives, viscosity/flowability modifiers, antifoaming agents, water resistance agents, printability improvers, optical brighteners, coloring agents such as dyes and colored pigments, lubricants, and water retention agents are also available. may also be added if necessary.

The coated paper thus obtained by the method of the present invention has various excellent and effective properties such as excellent printability and printing effects, namely, blister resistance, ink receptivity, ink setting property, and water resistance. It becomes something with characteristics.

[0046]

[Examples] The present invention will be explained in more detail with reference to Examples below. Note that % in the text represents weight % unless otherwise specified. Moreover, all viscosities are values at 25°C. In the examples below, the performance tests of the coated papers were conducted in the following manner.

Water resistance (a) Wet rub method: Drop about 0.1 ml of ion-exchanged water onto the coated surface, rub it 7 times with your fingertips, transfer the eluted amount to black paper, and check the eluted amount with the naked eye. I judged it. The evaluation criteria were as follows. Water resistance (poor) 1 to 5 (excellent) (b) Using a wet pick method RI tester (JIS K-5701), print after moistening the coated surface with a water supply roll, and visually observe the peeling condition. The judgment was made. The evaluation criteria were as follows. Water resistance (poor) 1-5 (excellent)

Ink receptivity (a) A method Using an RI tester, the coated surface was wetted with a water supply roll and then printed, and the ink receptivity was determined by observing with the naked eye. The evaluation criteria were as follows. Ink receptivity (poor) 1 to 5 (excellent) (b) Method B Printing was performed using an RI tester while kneading water into the ink, and the ink receptivity was determined by observing with the naked eye. The evaluation criteria were as follows. Ink receptivity (poor) 1-5 (excellent)

Ink Set Property After printing using an RI tester, commercially available high-quality paper was pressed at regular intervals, and the ink set-off property was observed and judged. The evaluation criteria were as follows. Ink setting (fast) 5 to 1 (slow)

Using a blister resistance RI tester, double-sided printing was performed on double-sided coated paper using offset rotary printing ink, and after adjusting the humidity, the paper was immersed in a heated silicone oil bath, and the amount of blisters generated was measured with the naked eye. It was judged. The evaluation criteria were as follows. Blister resistance (poor) 1-5 (excellent)

White chromaticity Measured according to JIS P-8123. Opacity was measured in accordance with JIS P-8138. Air permeability J-TAPPI No. Measured according to 5.

Example 1 Into a four-necked flask equipped with a thermometer, reflux condenser and stirring bar, 35 g (0.36 mol) of diallylamine, 50%
Acrylamide aqueous solution 34g (0.24mol), water 3
28 g and concentrated hydrochloric acid 36.5 g (0.36 mol) were charged, and the temperature was raised to 70° C. under a nitrogen atmosphere. Then, 0.4 g of ammonium persulfate was added as an initiator, and 6
Polymerize at 0 to 80°C for 10 hours to obtain a concentration of 15% and pH 3.
A cationic polymer A (aqueous solution) having a viscosity of 440 cps was obtained. This cationic polymer A was coated with commercially available high-quality paper (
basis weight 81.4 g/m2), solid content 0.
After coating at a concentration of 3 g/m2, the paper was dried for 15 seconds in a hot air dryer at 110°C to obtain a coated base paper coated with a cationic polymer. The anionic coating composition shown in Table 1 was applied to this coating base paper using a wire rod so that the coating amount was 15 g/m2 on one side, and the coating was applied in a hot air dryer at 120°C for 30 seconds. Dry. After further humidity conditioning for 16 hours at a temperature of 20℃ and a relative humidity of 65%, a temperature of 60℃ and a linear pressure of 6
The paper was passed through a super calendar twice under the condition of 0 kg/cm to obtain coated paper.

Note) ■ Ultra White 90: Clay manufactured by Engel Hard Minerals, USA ■ Carbital 90: Calcium carbonate manufactured by Fuji Kaolin Co., Ltd. ■ Violaze resin DS-10: Polyacrylic acid pigment manufactured by Sumitomo Chemical Co., Ltd. Dispersant ■ SN-307: Styrene-butadiene latex manufactured by Sumitomo Naugatac Co., Ltd. ■ Oji Ace A: Oxidized starch manufactured by Oji National Co., Ltd. Parts by weight represent the solid weight. ■ Total solid content: 60% ■ pH was adjusted to 9.0 with aqueous caustic soda solution. ■ The viscosity was 1600 cps (B type viscometer,
60 rpm).

The coated paper obtained as described above was subjected to the above-mentioned tests for water resistance, ink receptivity, ink setting, blister resistance, whiteness, opacity and air permeability. The test results are shown in Table-2.

Example 2 400 g of water was charged into the same experimental apparatus as in Example 1, and 8
The temperature was raised to 0°C, and 3 g of ammonium persulfate was added. There, 312 g of dimethylaminopropylacrylamide
(2.0 mol), a mixture of 190 g of acetic acid and 130 g of water was added dropwise over 5 hours, and the mixture was further kept at 70 to 90°C for 3 hours. During the process, 2 g of ammonium persulfate was added to terminate the polymerization reaction, and the nonvolatile content was 42% (polymer content was 30%).
Cationic polymer B (aqueous solution) having a pH of 5.8 and a viscosity of 640 cps was obtained. Using this cationic polymer B, a coated base paper was prepared which was previously coated with a cationic polymer in the same manner as in Example 1, and an anionic coating composition was further coated to obtain a coated paper. Regarding the coated paper obtained in this way,
Various tests similar to those in Example 1 were conducted, and the results are shown in Table 2.

Example 3 In the same apparatus as in Example 1, diethylenetriamine 103
(1 mol) and 233 g of water were charged and dissolved, and while keeping the internal temperature below 50°C, 130 g of epichlorohydrin was added.
(1.4 mol) was added dropwise to react. Next, 101 g (0.8 mol) of dimethyl sulfuric acid was gradually added and the reaction was carried out at a temperature of 30 to 50°C for 3 hours, followed by the addition of water to form a cationic polymer C (solid content 50%, viscosity 23 cps).
Aqueous solution) was obtained. Using this cationic polymer C,
A coated base paper was coated with a cationic polymer in advance in the same manner as in Example 1, and an anionic coating composition was further coated.
A coated paper was obtained. The coated paper thus obtained was subjected to various tests similar to those in Example 1, and the results are shown in Table 2.

Example 4 After charging 160 g of water into the same experimental apparatus as in Example 1, and further charging 31 g (0.3 mol) of diethylenetriamine and 90 g (1 mol) of a 50% dimethylamine aqueous solution, the internal temperature was lowered to 60°C. 139 g (1.5 mol) of epichlorohydrin was added dropwise at 60°C.
The temperature was further increased to 60 to 80°C for 6 hours. Then, after charging 100g of water and cooling it to 25℃, the pH was adjusted to 3.5 using concentrated hydrochloric acid, and the solid content was 40%.
Cationic polymer D (aqueous solution) with a viscosity of 150 cps
I got it. Example 1 Using this cationic polymer D
A coated base paper was coated with a cationic polymer in advance in the same manner as above, and an anionic coating composition was further coated to obtain a coated paper. The coated paper thus obtained was subjected to various tests similar to those in Example 1, and the results are shown in Table 2.

Example 5 After 622 g of water and 1.7 g of potassium persulfate were charged and dissolved in the same experimental apparatus as in Example 1, nitrogen gas was blown into the experimental apparatus and the reaction solution to eliminate oxygen in the reaction system. was removed. Note that nitrogen gas was also blown during the subsequent reaction. The temperature was raised to 70° C., and 284 g (2 mol) of a 50% aqueous acrylamide solution was added dropwise over 2 hours and 30 minutes. Next, keep warm at 70-80℃ for 3 hours and then heat to 25℃
144g (144g) of 50% dimethylamine aqueous solution
．． 6 mol) was slowly charged, and further 130 g (1.6 mol) of 37% formalin was slowly charged. After keeping the temperature at 30 to 50°C for 1 hour, it was cooled to 25°C. Finally, neutralize with sulfuric acid to obtain a solid content of 20% and a viscosity of 60%.
A cationic polymer E (aqueous solution) of 0 cps was obtained. Using this cationic polymer E, a coated base paper was prepared which was previously coated with a cationic polymer in the same manner as in Example 1, and then an anionic coating composition was further coated to obtain a coated paper. The coated paper thus obtained was subjected to various tests similar to those in Example 1, and the results are shown in Table 2.

Example 6 In the same experimental apparatus as in Example 1, diethylenetriamine 4
1 g (0.4 mol) and 240 g of water were charged, and then 185 g (2 mol) of epichlorohydrin was added while maintaining the internal temperature below 50°C. The reaction was further continued at 30 to 50°C for 2 hours and then cooled to obtain polymer F1. Separately, 292 g (2 mol) of triethylenetetramine and 60 g (1 mol) of urea were charged into the same experimental apparatus as in Example 1, and a deammonification reaction was carried out at 140 to 160°C for 3 hours, followed by 146 g (1 mol) of adipic acid. ) was added, and dehydration condensation was carried out at 140 to 160°C for 5 hours. then 1
After cooling to 00°C, 240 g (4 mol) of urea was added, and a deammonia reaction was performed at 120 to 140°C for 2 hours. Thereafter, 550 g of water was gradually added, followed by 162 g (2 mol) of 37% formalin, the pH was adjusted to 4 with sulfuric acid, and the mixture was kept at 60 to 80° C. for 4 hours. After cooling to 25°C and adjusting the pH to 6.5 with an aqueous caustic soda solution, the entire amount of polymer F1 synthesized earlier was charged.
It was made to react at 30-50 degreeC for 2 hours. Finally, the pH was adjusted to 5 with sulfuric acid to obtain cationic polymer F (aqueous solution). Using this cationic polymer F, a coated base paper was prepared which was previously coated with a cationic polymer in the same manner as in Example 1, and an anionic coating composition was further coated to obtain a coated paper. The coated paper thus obtained was subjected to various tests similar to those in Example 1, and the results are shown in Table 2.

Example 7 “Polymine SN” (B
A cationic polymer was coated in advance in the same manner as in Example 1 using ASF Co., Ltd.) to prepare a coated base paper, and an anionic coating composition was further coated to obtain a coated paper. The coated paper thus obtained was subjected to various tests similar to those in Example 1, and the results are shown in Table 2.

Example 8 A solution in which the cationic polymer A obtained in Example 1 and polyvinyl alcohol (abbreviated as PVA) (“Kuraray 105”, manufactured by Kuraray Co., Ltd.) were mixed at a solid content weight ratio of 1:1. Using this method, a coated base paper was preliminarily coated with a cationic polymer in the same manner as in Example 1, and an anionic coating composition was further coated to obtain a coated paper. The coated paper thus obtained was subjected to various tests similar to those in Example 1, and the results are shown in the table below.
Shown in 2.

Example 9 Diethylenetriamine 103 was added to the same apparatus as in Example 1.
g (1 mol) and adipic acid 138.7 g (0.9
140-160 while distilling water.
After reacting at ℃ for 20 hours, 668 g of water was gradually added and the mixture was cooled. Then, 148 g (1.6 mol) of epichlorohydrin was charged at a temperature of 40°C or lower, and the mixture was kept at a temperature of 40 to 60°C for 12 hours. After that, cool it down, add 298g of water, and adjust the pH to 3.5 with concentrated hydrochloric acid.
A cationic polymer G having a solid content of 25% and a viscosity of 200 cps was obtained. Using this cationic polymer G, a coated base paper was prepared which was previously coated with a cationic polymer in the same manner as in Example 1, and an anionic coating composition was further coated to obtain a coated paper. The coated paper thus obtained was subjected to various tests similar to those in Example 1, and the results are shown in Table 2.
It was shown to.

Comparative Example 1 The same anionic coating composition as in Example 1 was applied directly to the same commercially available high-quality paper as used in Example 1 without coating with the cationic polymer. Got paper. The coated paper thus obtained was subjected to various tests similar to those in Example 1, and the results are shown in Table 2.

Comparative Example 2 PVA (“Kuraray 105”) was used instead of the cationic polymer.
A coated base paper was obtained in the same manner as in Example 1, except that ``Kuraray Co., Ltd.'' was used, and an anionic coating composition was further applied to obtain a coated paper.About the thus obtained coated paper Various tests similar to those in Example 1 were conducted, and the results are shown in Table 2.

Comparative Example 3 A base paper coated with aluminum sulfate was obtained in the same manner as in Example 1 except that a 15% aluminum sulfate aqueous solution was used instead of the cationic polymer, and further coated with an anionic coating composition. Coated paper was obtained. The coated paper thus obtained was subjected to various tests similar to those in Example 1, and the results are shown in Table 2.

[0066]

[0067]

[0068]

[Effects of the Invention] The coated paper produced by the method of the present invention has excellent water resistance, ink receptivity, ink setting property, and blister resistance, and also has improved whiteness and opacity.
Has useful and improved printability and printing effect.

Claims (1)

[Claims] Claim 1: Coating a cationic polymer on a coating base paper,
A method for producing coated paper, which comprises coating thereon an anionic coating composition mainly consisting of a pigment and an aqueous binder.