JP2987996B2 - Manufacturing method of coated paper - Google Patents

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 coated paper by applying an anionic coating composition mainly composed of a pigment and an aqueous binder to a coated base paper. The present invention relates to a method for producing a coated paper having improved quality such as giving excellent printability and printing effect.

[0002]

2. Description of the Related Art Coated paper formed by coating an anionic coating composition mainly composed of a pigment and an aqueous binder onto a coated base paper is characterized by its excellent printing effect and the like. Widely used in such as. However, with these coated papers, further quality improvement efforts have been continued with the sophistication and diversification of quality requirements and the increase in printing speed. Particularly in offset printing, which accounts for most of the printing methods, improvements and improvements in ink acceptability and wet topic strength under the influence of shampoo water, and improvements in blister resistance in rotary printing, etc.
Improvement is an important issue in the industry.

Conventionally, various methods have been proposed to solve such problems, and efforts have been made to improve them. However, the effects of these methods are not always satisfactory due to an increase in quality requirements. Some had significant disadvantages.

[0004] For example, the quality of coated paper can be greatly changed by adjusting the type, composition or composition of pigments and aqueous binders, but the improvement of certain properties often accompanies the deterioration of other properties. However, there is a limit to the improvement by such a method. On the other hand, for example, JP-A-1-97296,
And HG Gatterer et al., PTS 1983 Coating Seminar Presentation Paper (Japanese translation is “PTS 1983 Coating Seminar”, published by Uni Publishing Co., Ltd., No. 17-3)
(Published on page 2) proposes a cationic coating composition, and JP-A-2-84598 proposes a coating composition containing a cationic resin. However, from the problem of the coating composition preparation method and coating suitability,
It has not yet been widely used. It is also known to use water-proofing agents and printability improvers such as polyamide polyurea-based resins, which are effective in the industry because they are effective in improving water resistance, ink receptivity, and blister resistance. However, the degree of improvement is not necessarily sufficient in the recent rise in quality requirements.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, that is, by applying an anionic coating composition mainly comprising a pigment and an aqueous binder to a base paper for coating. It is an object of the present invention to provide a method for producing coated paper capable of highly improving printability and printing effects such as water resistance, ink acceptability, and blister resistance.

[0006]

Means for Solving the Problems As a result of intensive studies, the present inventors have produced coated paper by applying an anionic coating composition mainly composed of a pigment and an aqueous binder to a coated base paper. In doing so, it has been found that by pre-coating a cationic polymer onto the coated base paper, the printability and printing effect of the obtained coated paper can be significantly improved, and the present invention has been achieved. That is, the present invention provides a method for producing a coated paper, which comprises coating a cationic polymer on a coated base paper, and coating an anionic coating composition mainly comprising a pigment and an aqueous binder thereon. To provide.

The present invention is characterized in that a base polymer is coated with a cationic polymer in advance, and the base polymer coated with the cationic polymer is coated with an anionic coating mainly composed of a pigment and an aqueous binder. When coating the coating composition, it is considered that the affinity between the cationic polymer and the anionic coating composition promotes color setting, improves coating properties, and makes the coating layer porous. The resulting coated paper is water resistant, ink receptive, blister resistant,
A remarkable improvement in ink setting properties and the like is observed.
Hereinafter, the present invention will be described in more detail.

[0008] The cationic polymer used in the present invention is:
It refers to one in which the main polymer dissociates into cations in an aqueous medium, and typical cationic groups include primary, secondary and tertiary amino groups, and quaternary ammonium salts. Any cationic polymer can be used as long as it is such a cationic polymer. The type of the cationic polymer is not particularly limited. Examples of the cationic polymer preferably used in the present invention include the following.

A) a polyalkylene polyamide obtained by dehydration-condensation of a polyalkylene polyamine and a dibasic carboxylic acid; b) a polyalkylene polyurea obtained by deammonia condensation of a polyalkylene polyamine and urea: c) depolymerization of the polyalkylene polyamide and urea D) a polyamino epoxy resin obtained by reacting an amino group-containing compound with epihalohydrin; e) a reaction product obtained by further reacting an aldehyde with any of the polymers a) to d) described above; f) A reaction product obtained by reacting any of the polymers a) to d) with an alkylating agent; g) a ring-opened polymer of ethyleneimine; h) a cationic vinyl monomer polymerized alone;
Or a polymer copolymerized with another copolymerizable monomer; i) a homopolymer of an N-vinylamide monomer or a hydrolyzate of a copolymer with another copolymerizable monomer; j) a polymer having active hydrogen A) a Mannich reactant obtained by reacting ammonia, a primary amine or a secondary amine with formaldehyde; k) a reactant of a polymer having active hydrogen with a cationizing agent; l) a polymer having active hydrogen with ammonia or amines M) chitosan obtained by hydrolyzing chitin; n) a polymer having active hydrogen and any one of the above-mentioned polymers a) to m) are reacted with an aldehyde, epihalohydrin,
A block copolymer reacted with a crosslinking agent such as polyisocyanate.

Specific examples of the starting compounds used for producing these various cationic polymers are shown below.

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

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

Examples of the amino group-containing compound used in d) include ammonia, various amines, polyalkylene polyamine, polyalkylene polyamide, polyalkylene polyurea, and polyamide polyurea.

The epihalohydrin used in the above d), l) and n) is exemplified by epichlorohydrin, epibromohydrin and the like.

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

As the alkylating agent in the above f),
The following various types can be used. In the general formula R ¹ -X [wherein, R ¹ is a lower alkyl group (e.g., having about 1 to 6 carbon atoms), lower alkenyl groups (for example, about 2 to 6 carbon atoms),
Represents a benzyl group or a phenoxyethyl group, and X represents a halogen atom]. Preferred examples include, for example, methyl chloride, ethyl chloride, propyl chloride, allyl chloride, benzyl chloride, phenoxyethyl chloride, and bromides and iodides corresponding to these chlorides.

A dialkyl sulfite represented by the general formula (R ² O) ₂ SO _v [wherein R ² represents a lower alkyl group (for example, having about 1 to 6 carbon atoms) and v represents 1 or 2]; Dialkyl sulfate. Preferred examples include dimethyl sulphite, diethyl sulphite, dimethyl sulphate, diethyl sulphate and the like.

General formula

[0019]

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Wherein R ³ represents a hydrogen atom, a lower alkyl group (for example, about 1 to 6 carbon atoms), a hydroxy lower alkyl group (for example, about 1 to 6 carbon atoms) or a phenyl group; And its derivatives.
Preferred examples include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, glycidol and the like.

General formula

[0022]

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Wherein X represents a halogen atom and w represents 1, 2 or 3; and an epihalohydrin represented by the formula:
Preferred examples include epichlorohydrin, epibromohydrin and the like.

General formula HOCH ₂ (CH ₂ ) _w X wherein X represents a halogen atom and w is 1, 2 or 3
A monohalohydrin represented by the formula: Preferred examples include ethylene chlorohydrin, ethylene bromohydrin and the like.

General formula

[0026]

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Wherein X represents a halogen atom, one of Y and Z represents a halogen atom, and the other represents a hydroxyl group. Preferred examples are 1,3-
Dichloro-2-propanol, 2,3-dichloro-1-
And propanol.

The cationic vinyl monomer used in the above h) includes dimethylaminoethyl (meth)
Acrylate, dimethylaminopropyl (meth) acrylate, dimethylaminoethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide,
And quaternized products thereof, and allylamine, diallylamine, triallylamine, vinylpyrrolidone, diallyldimethylammonium salt and the like.

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

Examples of the polymer having active hydrogen used in j), k), l) and n) include starches,
Examples thereof include proteins such as polyvinyl alcohol, polyacrylamide and casein, and methylcellulose.

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

[0032]

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[0033] [In these formulas, Q represents a divalent aliphatic group or an aromatic group, R ⁴ and R ⁵ each independently represents a lower alkyl group (for example, about 1 to 6 carbon atoms), R ⁶
Represents a hydrogen atom or a lower alkyl group (for example, having 1 to 6 carbon atoms)
A ⁻ represents an anion such as a halide ion or a sulfate ion, and L represents a leaving group such as a halogen atom, a sulfonate group or a sulfate group.]

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

In the above formula, examples of the sulfonic ester group represented by L include a methanesulfonic acid residue (CH ₃ S
O ₂ O—), ethanesulfonic acid residue (C ₂ H ₅ SO ₂ O)
-), benzenesulfonic acid residue _{(C 6 H 5 SO 2 O-} ),
An alkyl or aryl sulfonic acid ester group such as a toluene sulfonic acid residue (CH ₃ C ₆ H ₄ SO ₂ O—) may be mentioned, and a sulfate ester group may be a sulfuric acid residue (HOSO ₂ O—). For example, a methyl sulfate residue (C
H ₃ OSO ₂ O-), ethyl sulfate residue (C ₂ H ₅ OSO ₂
O-), include esters of alkyl or aryl sulfates, such as phenyl acid residues _{(C 6 H 5 OSO 2 O-} ).

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

In addition to cationic polymers, polyvalent metal salts such as sulfates and chlorides of aluminum, calcium, magnesium and the like are considered to have an interaction with the anionic coating composition intended in the present invention. However, these are not suitable because their effects cannot be obtained unless they are applied in a large amount to the coated base paper, and they have an adverse effect on the whiteness and storage stability of the coated base paper and coated paper. .

In the present invention, the above-mentioned cationic polymers can be used alone or in combination of two or more. At this time, surface paper strength enhancers such as starches, polyvinyl alcohols, and polyacrylamides having good compatibility, and various surface sizing agents may be used in combination. Furthermore, a fluorescent whitening agent, a preservative, an antifoaming agent, a lubricant, a water repellent, a water-proofing agent, a colorant, and the like can be blended as necessary while considering compatibility.

The cationic polymer is formed into a coating solution having an appropriate concentration in consideration of the coating amount and suitability for a coating machine, and is coated on a base paper using a size press coater, a gate roll coater, a machine calendar, a spray coater or the like. Is coated on one or both sides, but it is particularly preferable to use an on-machine coater. Thereafter, by performing necessary drying, a base paper coated with a cationic polymer in advance is obtained. The coating amount of the cationic polymer naturally varies depending on the type of the cationic polymer to be used, etc.
0.01 to ² g / m ² · one side is preferred.

In the present invention, an anionic coating composition containing a pigment and an aqueous binder is applied to a base paper coated with a cationic polymer thus obtained in advance by a conventional method, that is, a size press coater, a gate roll. Coater, air knife coater, bill blade coater,
By coating with a cast coater, blade coater, kiss roll coater and the like, and performing necessary drying treatment and smoothing treatment, it is possible to produce coated paper with improved printability and printing effect aimed at. .

There are no particular restrictions on the composition or concentration of the coating composition containing the pigment and the aqueous binder used herein, and the only condition is that the coating composition be anionic. And about 5 to 50 parts by weight of an aqueous binder and a solid content concentration of about 30 to 70% by weight.

The anionic coating composition referred to herein is the one most widely used for coating paper, and contains an anionic component in any form such as a pigment, an aqueous binder, and a dispersant. What is necessary is just to show the anionic property as the whole composition. For example, a white inorganic pigment or an organic synthetic white pigment is dispersed and slurried using an anionic dispersant such as sodium tripolyphosphate or a polyacrylate dispersant, and a water-soluble binder and / or a water-emulsified pigment is used. There is a coating composition containing a water-dispersed binder.

Among the pigments, examples of white inorganic pigments include kaolin, calcium carbonate, titanium oxide, aluminum hydroxide, and satin white. Examples of organic synthetic white pigments include polystyrene resin and urea / formaldehyde. Resins. Further, among the aqueous binders, examples of the water-soluble binder include oxidized starch, phosphated starch, carboxymethylcellulose, casein, polyvinyl alcohol, and the like,
Examples of the water-emulsified water-dispersed binder include styrene-butadiene-based latex, vinyl acetate-based resin, ethylene vinyl acetate-based resin, and acrylate-based resin.

The pigments serving as components of the anionic coating composition can be used alone or as a mixture of two or more, and the aqueous binders can be used alone or as a mixture of two or more. Can be used.
In addition, various auxiliaries such as preservatives, viscosity / fluidity regulators, defoamers, waterproofing agents, printability improvers, fluorescent whitening agents, coloring agents such as dyes and colored pigments, lubricants, water retention agents, etc. Can also be added as necessary.

The coated paper obtained by the method of the present invention has various excellent effective properties such as excellent printability and printing effect, that is, blister resistance, ink acceptability, ink setting property, water resistance and the like. It has characteristics.

[0046]

The present invention will be described in more detail with reference to the following examples. In addition,% in a sentence represents weight% unless there is particular notice. All viscosities are values at 25 ° C.
In the following examples, the performance test of the coated paper was performed by the following method.

Water resistance (a) Wet rub method About 0.1 ml of ion-exchanged water was dropped on the coated surface, rubbed with a fingertip seven times, and the eluted amount was transferred to black paper, and the elution amount was visually determined. . The judgment criteria were as follows. Water resistance (poor) 1-5 (excellent) (b) Wet topic method Using a RI tester (JIS K-5701), wet the coated surface with a water supply roll, print, and observe the peeling state with the naked eye Was determined. The judgment criteria were as follows. Water resistance (poor) 1-5 (excellent)

Ink Acceptability (A) Method A Using a RI tester, the coated surface was wetted with a water supply roll and then printed, and the ink acceptability was visually observed and judged. The judgment criteria were as follows. Ink acceptability (poor) 1 to 5 (excellent) (b) Method B Using an RI tester, printing was performed while water was mixed into the ink, and the ink acceptability was visually observed and judged. The judgment criteria were as follows. Ink acceptability (poor) 1-5 (excellent)

Ink setting properties 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 judgment criteria were as follows. Ink setting (fast) 5-1 (slow)

Using a blister-resistant RI tester, double-sided printing was performed on a double-side coated paper using an offset rotary printing ink, and after humidity control, the paper was immersed in a heated silicone oil bath. Was determined. The judgment criteria were as follows. Blister resistance (poor) 1-5 (excellent)

[0051] was measured according to the white color of JIS P-8123. Opacity Measured according to JIS P-8138. The air permeability was measured in accordance with J-TAPPI No. 5.

Example 1 A four-necked flask equipped with a thermometer, a reflux condenser and a stirring rod was charged with 35 g (0.36 mol) of diallylamine, 34 g (0.24 mol) of a 50% aqueous acrylamide solution, 328 g of water and 36.5 g of concentrated hydrochloric acid (0.36 mol). Mol) and heated to 70 ° C. under a nitrogen atmosphere. Then, 0.4 g of ammonium persulfate was added as an initiator and polymerized at 60 to 80 ° C. for 10 hours to obtain a cationic polymer A (aqueous solution) having a concentration of 15%, a pH of 3, and a viscosity of 440 cps. This cationic polymer A was coated on a commercially available high-quality paper (rice basis weight: 81.4 g / m ² ) so as to have a solid content of 0.3 g / m ^2.
And dried with a hot air drier for 15 seconds to obtain a coated base paper coated with a cationic polymer. An 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 / m ^2.
For 30 seconds. At a temperature of 20 ° C,
After conditioning for 16 hours at a relative humidity of 65%, the paper was passed twice through a super calender under the conditions of a temperature of 60 ° C. and a linear pressure of 60 kg / cm to obtain a coated paper.

[0053] Note) Ultra White 90: Clay Carbital 90 manufactured by Engel Hard Minerals Co., Ltd. USA: Calcium carbonate Sumireze Resin manufactured by Fuji Kaolin Co., Ltd. DS-10: Polyacrylic acid pigment dispersant SN-307 manufactured by Sumitomo Chemical Co., Ltd. Styrene butadiene-based latex manufactured by Sumitomo Nogatack Co., Ltd. Oji Ace A: Oxidized starch manufactured by Oji National Co., Ltd. Parts by weight indicate solid content weight. The pH of the total solid content 60% was adjusted to 9.0 with a sodium hydroxide aqueous solution. The viscosity was 1600 cps (B-type viscometer, 60 rp.
m).

The coated paper obtained as described above was subjected to the above-described tests of water resistance, ink acceptability, ink setting property, 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 mixed solution 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. On the way, 2 g of ammonium persulfate was added to terminate the polymerization reaction, the non-volatile content was 42% (polymer content was 30%), the pH was
A cationic polymer B (aqueous solution) having a viscosity of 5.8 and a viscosity of 640 cps was obtained. This cationic polymer B was used as a coating base paper previously coated with a cationic polymer in the same manner as in Example 1, and further an anionic coating composition was applied to obtain a coated paper. About the coated paper thus obtained, Example 1
Various tests similar to those described above were performed, and the results are shown in Table 2.

Example 3 The same apparatus as in Example 1 was used except that diethylenetriamine 103 was used.
g (1 mol) and 233 g of water were charged and dissolved, and while keeping the internal temperature at 50 ° C. or lower, 130 g of epichlorohydrin was added.
(1.4 mol) was added dropwise and reacted. Then, 101 g (0.8 mol) of dimethyl sulfuric acid was gradually added, and the temperature was adjusted to 30-5.
After reacting at 0 ° C. for 3 hours, water was added to obtain a solid content of 50%.
%, A cationic polymer C (aqueous solution) having a viscosity of 23 cps. Using this cationic polymer C, a coated base paper preliminarily coated with a cationic polymer was prepared in the same manner as in Example 1, and an anionic coating composition was further coated to obtain a coated paper. Various tests similar to those in Example 1 were performed on the coated paper thus obtained, and the results are shown in Table 2.

Example 4 160 g of water was charged into the same experimental apparatus as in Example 1, and 31 g (0.3 mol) of diethylenetriamine and 50 g of diethylenetriamine were added.
% Dimethylamine aqueous solution (90 g, 1 mol), the internal temperature was kept at 60 ° C. or lower, and epichlorohydrin 1 was added.
39 g (1.5 mol) was added dropwise, then the temperature was raised to 60 ° C, and the temperature was further kept at 60 to 80 ° C for 6 hours. And water 1
After cooling to 25 ° C., the pH was adjusted to 3.5 using concentrated hydrochloric acid, the solid content was 40%, and the viscosity was 150 cp.
s of cationic polymer D (aqueous solution) was obtained. This cationic polymer D was used as a coating base paper previously coated with a cationic polymer in the same manner as in Example 1, and further an anionic coating composition was applied to obtain a coated paper. Various tests similar to those in Example 1 were performed on the coated paper thus obtained, and the results are shown in Table 2.

Example 5 622 g of water and 1.7 g of potassium persulfate were charged and dissolved in the same experimental apparatus as in Example 1, and nitrogen gas was blown into the experimental apparatus and the reaction solution to remove oxygen in the reaction system. Removed. During the subsequent reaction, nitrogen gas was blown. The temperature was raised to 70 ° C., and 284 g (2 mol) of a 50% acrylamide aqueous solution was added dropwise over 2 hours and 30 minutes. Then, the mixture was kept at 70-80 ° C. for 3 hours, cooled to 25 ° C., and 144 g of a 50% aqueous dimethylamine solution (1.6 g
Mol) slowly and then 37% formalin 13
0 g (1.6 mol) were slowly charged. And 30-5
After keeping the temperature at 0 ° C for 1 hour, it was cooled to 25 ° C. Finally, the mixture was neutralized with sulfuric acid to obtain a cationic polymer E (aqueous solution) having a solid content of 20% and a viscosity of 600 cps. Using this cationic polymer E, a coated base paper preliminarily coated with a cationic polymer in the same manner as in Example 1 was further coated with an anionic coating composition to obtain a coated paper. Various tests similar to those in Example 1 were performed on the coated paper thus obtained, and the results are shown in Table 2.

Example 6 An experimental apparatus similar to that of Example 1 was used.
1 g (0.4 mol) and 240 g of water were added, and epichlorohydrin 1 was added while maintaining the internal temperature at 50 ° C. or lower.
85 g (2 mol) were added. Further after cooling was continued for 2 hours at 30 to 50 ° C., to obtain a polymer F _1. 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, a deammonification reaction was carried out at 140 to 160 ° C. for 3 hours, and 146 g (1 mol) of adipic acid were further added. ) And add 1
Dehydration condensation was carried out at 40 to 160 ° C for 5 hours. Then 100
After cooling to ℃, 240 g (4 mol) of urea was added,
A deammonification reaction was performed at 120 to 140 ° C. for 2 hours.
Thereafter, 550 g of water was gradually added, 162 g (2 mol) of 37% formalin was further added, the pH was adjusted to 4 with sulfuric acid, and the temperature was kept at 60 to 80 ° C for 4 hours. Then cooled to 25 ° C., after adjusted to 6.5 and the pH at aqueous sodium hydroxide solution, the total amount charged polymer F ₁ the previously synthesized, 30
The reaction was performed at 50 ° C. for 2 hours. Finally, the pH was adjusted to 5 with sulfuric acid to obtain a cationic polymer F (aqueous solution). Using this cationic polymer F, a coating base paper preliminarily coated with a cationic polymer was prepared in the same manner as in Example 1, and an anionic coating composition was further coated to obtain a coated paper. Various tests similar to those in Example 1 were performed on the coated paper thus obtained, and the results are shown in Table 2.

Example 7 Polyethyleneimine derivative “Polymin SN” (BA
As in Example 1, a coated base paper was previously coated with a cationic polymer, and an anionic coating composition was further coated to obtain a coated paper. Various tests similar to those in Example 1 were performed on the coated paper thus obtained, 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”, a product of Kuraray Co., Ltd.) was mixed at a solid content weight ratio of 1: 1. In the same manner as in Example 1 to obtain a coated base paper previously coated with a cationic polymer, and further coated with an anionic coating composition to obtain a coated paper. The coated paper thus obtained was subjected to various tests similar to those in Example 1, and the results were shown in Table 1.
2 is shown.

Example 9 In the same apparatus as in Example 1, diethylenetriamine 103 was added.
g (1 mol) and 138.7 g (0.95 mol) of adipic acid were reacted at 140 to 160 ° C. for 20 hours while distilling water, and then 668 g of water was gradually charged and cooled. Then, 148 g (1.6 mol) of epichlorohydrin was charged at a temperature of 40 ° C. or lower, and further 40 to 60 ° C.
For 12 hours. Then cool down and water 29
8 g was charged and the pH was adjusted to 3.5 with concentrated hydrochloric acid to obtain a cationic polymer G having a solid content of 25% and a viscosity of 200 cps. Using this cationic polymer G, a coated base paper previously coated with a cationic polymer in the same manner as in Example 1 was used.
Further, the anionic coating composition was applied to obtain a coated paper. Various tests similar to those in Example 1 were performed on the coated paper thus obtained, and the results are shown in Table 2.

Comparative Example 1 The same anionic coating composition as in Example 1 was directly applied to the same commercially available high-quality paper as used in Example 1 without coating the cationic polymer. I got the paper. Various tests similar to those in Example 1 were performed on the coated paper thus obtained, and the results are shown in Table 2.

Comparative Example 2 PVA (Kuraray 10) was used in place of the cationic polymer.
Coating base paper was obtained in the same manner as in Example 1 except that 5 "(Kuraray Co., Ltd.) was used, and an anionic coating composition was further coated to obtain a coated paper. Were tested in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Example 3 A coating base paper coated with aluminum sulfate was obtained in the same manner as in Example 1 except that a 15% aqueous solution of aluminum sulfate was used in place of the cationic polymer, and an anionic coating composition was further coated. To obtain a coated paper. Various tests similar to those in Example 1 were performed on the coated paper thus obtained, and the results are shown in Table 2.

[0066]

[0067]

[0068]

The coated paper produced by the method of the present invention is excellent in water resistance, ink receptivity, ink setting property and blister resistance, and has improved whiteness and opacity.
It has useful and improved printability and printing effect.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) D21H 19/44-19/62

Claims (1)

(57) [Claims] Claims: 1. Coating base paper with a cationic polymer,
A method for producing coated paper, comprising applying an anionic coating composition mainly comprising a pigment and an aqueous binder thereon.