JPH0987995A - Coating composition for paper - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide a paper coating composition having a high solid content but excellent in coating suitability and capable of improving the quality of coated paper. SOLUTION: Each of the following components (I) to (III) is contained, and
A coating composition for paper having a solid content of more than 0% by weight. (I) A pigment in which at least 40% by weight of the total pigment is calcium carbonate, (II) an aqueous binder, and (III) at least (a) an amine selected from alkylenediamines and polyalkylenepolyamines, and (b) an amine.
(a) 0.5 to 0.9 mol of urea per 1 mol of the total of primary and secondary amino groups, and (c) aldehydes, epihalohydrins and α, γ-dihalo-β- The three components of the compound selected from hydrins are amine (a) and urea
A water-soluble resin obtained by the reaction so that the number of moles of amino groups consumed as a result of the reaction with (b) exceeds the number of moles of the urea (b) used in the reaction.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a paper coating composition containing a pigment and an aqueous binder.
More specifically, the present invention relates to a paper coating composition having a high solid content and capable of imparting excellent printability and printing effect to paper.

The term "paper" used in this specification has a broad sense, and includes paper and paperboard in a narrow sense.

[0003]

2. Description of the Related Art A coated paper obtained by applying a coating composition mainly composed of a pigment and an aqueous binder to paper and performing necessary treatments such as drying and calendering is characterized by its excellent printing effect. Therefore, it is widely used in commercial printed matter, magazines, books, etc., but with the sophistication of quality requirements and the speeding up of printing, efforts to improve the quality of coated paper are still ongoing. Especially in offset printing, which occupies most of the printing, improvement and improvement of ink acceptability under the influence of squeezing water, water resistance such as wet pick, and blister resistance in rotary printing are important issues in the industry. There is.

Conventionally, melamine-formaldehyde resin, urea-formaldehyde resin, or polyamide polyurea-formaldehyde resin,
For example, there is known a method of adding a water resistance agent, a printability improving agent and the like as shown in JP-B-44-11667 and JP-B-59-32597. However, all of these conventional waterproofing agents and printability improvers have effective merits, but on the other hand, serious defects or insufficient effects are observed in some properties, and therefore, they are not always practically satisfactory. Not profitable.

For example, aminoplast resins such as melamine-formaldehyde resin and urea-formaldehyde resin not only generate a large amount of formaldehyde during work or from coated paper, but also have an effect of improving ink acceptability and blister resistance. Is hardly obtained, and when the pH of the coating composition is high, the water resistance effect is less likely to be exhibited.

Polyamide polyurea-formaldehyde resin is effective in improving not only water resistance but also ink acceptability and blister resistance, but the degree of improvement is
It has not always been enough to meet the recent demand for higher quality coated paper. Therefore, efforts have been made to further improve the quality, and further improvements have been attempted by, for example, JP-A-62-104995, JP-A-4-100997, and JP-A-4-263696. But,
Since the demand for coated paper quality has increased since then, higher performance has been required.

[0007]

In addition to the above problems, there are active studies on rationalization in the coated paper manufacturing industry in recent years, and in order to reduce the heat energy cost for drying coated paper, solid Attention has been focused on a method of using a coating composition having a high concentration or a coating composition having a relatively low calcium carbonate content, which is relatively inexpensive among pigments. However, in the former case, particularly when a printability improver is added, problems such as streak during coating, which are derived from the fluidity of the coating composition, are likely to occur, and in the latter case, in the latter case, blister is further increased. Problem is likely to occur.
Therefore, there has been an urgent need to develop a drug having excellent operability that does not cause such a problem.

The object of the present invention is to meet the demand for the quality of coated paper, and to impart higher ink acceptability and water resistance to the paper, and to further improve the quality of the coated paper. It is to provide a coating composition for paper. Another object of the present invention is to provide a coating composition for paper which has a high solid content and is less likely to cause problems such as streaks during the production of coated paper.

As a result of intensive studies for solving the above problems, the present inventors have found that a water-soluble resin synthesized by a specific reaction method is a pigment-containing system containing a large amount of calcium carbonate and having a high solid content concentration. The present invention has been completed by finding that a coating composition which is effective for a composition and which contains such a water-soluble resin imparts excellent performance to paper.

[0010]

That is, the present invention comprises the following components (I), (II) and (III) as essential components:
It is intended to provide a coating composition for paper having a solid content of more than 0% by weight.

(I) A pigment in which at least 40% by weight of the total pigment is calcium carbonate, (II) an aqueous binder, (III) at least (a) an amine selected from alkylenediamines and polyalkylenepolyamines, and (b) an amine ( a) 0.5 to 0.9 mol of urea relative to 1 mol of the primary and secondary amino groups in total, and (c) aldehydes, epihalohydrins and α, γ-dihalo-β-hydrins The three components of the compound selected from the above, so that the number of moles of the amino group consumed as a result of the reaction of the amine (a) and the urea (b) exceeds the number of moles of the urea (b) used in the reaction. Water-soluble resin obtained by reaction.

Hereinafter, the present invention will be described in more detail.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Pigments to be used as components of paper coating compositions
As (I), in the present invention, based on the total amount of pigment (I),
40% by weight or more of calcium carbonate is used. The calcium carbonate may be either heavy or light. In addition to calcium carbonate, other white inorganic pigments and / or white organic pigments that have been conventionally used for coating paper can be used in combination. Examples of white inorganic pigments include kaolin, talc, aluminum hydroxide, satin white, and titanium oxide. Examples of white organic pigments include polystyrene, melamine-formaldehyde resin, and urea-formaldehyde resin.
Furthermore, a colored inorganic or organic pigment can be used in combination as required. Of course, calcium carbonate may be used as the only pigment, but in general it is preferable to use other white pigments together, for example, 40 to 80% by weight of calcium carbonate based on the total amount of pigment (I). like,
It is preferable to use other pigments in combination.

Another component, an aqueous binder (II)
Can be any of those conventionally used for coating paper, and a water-soluble binder or a water-emulsified binder can be used. Examples of the water-soluble binder include unmodified or modified starches such as oxidized starch and phosphate esterified starch, water-soluble proteins such as polyvinyl alcohol, casein and gelatin, and carboxymethyl cellulose. Examples include modified celluloses. Examples of the water-emulsified binder include styrene-butadiene resin, vinyl acetate resin, ethylene-vinyl acetate resin, and methyl methacrylate resin. These aqueous binders may be used alone or in combination of two or more.

In the present invention, in addition to the pigment (I) and the aqueous binder (II), a specific water-soluble resin (III) is also used in combination. The water-soluble resin (III) is (a) an amine selected from alkylenediamine and polyalkylenepolyamine,
It is obtained by reacting at least three components of (b) ureas and (c) compounds selected from aldehydes, epihalohydrins and α, γ-dihalo-β-hydrins. Here, the ureas (b) are used in the range of 0.5 to 0.9 mol per 1 mol of the total of the primary and secondary amino groups in the amine (a). Further, the reaction is carried out such that the number of moles of the amino group consumed as a result of the reaction between the amine (a) and the urea (b) exceeds the number of moles of the urea (b) used in the reaction.

Amine used for producing water-soluble resin (III)
Examples of (a) include aliphatic diamines such as ethylenediamine, 1,2-propanediamine, 1,3-propanediamine, hexamethylenediamine, and diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine. , Iminobispropylamine, 3-azahexane-1,6-diamine, and 4,7-diazadecane-1,10-diamine. Among these, diethylenetriamine and triethylenetetramine are industrially advantageous. The amine (a) can be used alone or in combination of two or more kinds.

Examples of ureas (b) include urea, thiourea, guanylurea, methylurea and dimethylurea. From an industrial point of view, urea is preferably used. The ureas (b) are primary and secondary compounds in the amine (a).
It is used in the range of 0.5 to 0.9 mol based on 1 mol of the total of the primary amino groups.

Examples of the aldehydes in the compound (c) include alkylaldehydes such as formaldehyde, acetaldehyde and propylaldehyde, glyoxal, alkyldialdehydes such as propanedial and butanedial. Industrially, formaldehyde and glyoxal are preferred.
These aldehydes can be used alone or in combination of two or more.

Epihalohydrins are represented by the following general formula.

[0020]

In the formula, X represents a halogen atom, w is 1,
Represents 2 or 3. Preferred examples of epihalohydrins include epichlorohydrin, epibromohydrin and the like. These epihalohydrins may be used alone or in combination of two or more.

The α, γ-dihalo-β-hydrins are represented by the following general formula.

[0023]

In the formula, Y and Z represent a halogen atom. Examples of such α, γ-dihalo-β-hydrins include 1,3-dichloro-2-propanol and the like.

In the present invention, one or more compounds (c) selected from aldehydes, epihalohydrins and α, γ-dihalo-β-hydrins are used. Therefore, of course, these may be used alone or in combination of two or more kinds. For example,
Aldehydes and epihalohydrins can be used in combination, or aldehydes and α, γ-dihalo-β can be used.
-Hydrin may be used in combination, or aldehydes, epihalohydrins and α, γ-dihalo-β-hydrins may be used in combination. The compound (c) is generally used in the range of 0.1 to 2 mol, preferably 0.2 to 1 mol, per 1 mol of the amine (a).

The water-soluble resin (III) used in the present invention can be obtained by reacting at least three components of the amine (a), urea (b) and compound (c) as described above. The water-soluble resin (III) may be one obtained by reacting other components in addition to these three components. As the additional reaction component preferably used, a dibasic carboxylic acid compound (d) and an alicyclic compound (e) selected from an alicyclic amine and an alicyclic epoxy compound having at least one active hydrogen are Can be mentioned.

The dibasic carboxylic acid compound (d) is a compound having two carboxyl groups in the molecule or a compound derived therefrom, for example, a free acid, an ester, an acid anhydride or the like. You can

Dibasic carboxylic acids include aliphatic, aromatic,
It may be either alicyclic. Examples of the free acid include aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, sebacic acid, maleic acid and fumaric acid, aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid, and further tetracarboxylic acid. Hydrophthalic acid, hexahydrophthalic acid, cyclohexane-1,3-or-
1,4-dicarboxylic acid, cyclopentanedicarboxylic acid,
Alicyclic dicarboxylic acids such as 3- or 4-methyltetrahydrophthalic acid and 3- or 4-methylhexahydrophthalic acid are mentioned. Incidentally, when the alicyclic group has an unsaturated bond, and the position of the unsaturated bond is not clearly indicated,
It should be understood that the position of the unsaturated bond is arbitrary, and the same applies to the following description.

As the dibasic carboxylic acid compound (d), in addition to these free dibasic carboxylic acids, their esters, acid anhydrides and the like can be used. Examples of the esters include mono- or di-esters of the above free acids and lower alcohols, and polyesters of the above free acids and glycols. Specific examples of the acid anhydride include succinic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and 3-hydrophthalic anhydride.
Alternatively, 4-methyltetrahydrophthalic anhydride, 3- or 4-methylhexahydrophthalic anhydride, etc. may be mentioned.

Polyesters, which are the reaction products of dibasic carboxylic acids and glycols, are also advantageously used, but those having free carboxyl groups are preferred.
Examples of glycols used here include alkylene glycols such as ethylene glycol, propylene glycol and butanediol, cycloalkylene glycols such as cyclopentanediol and cyclohexanediol, alkenylene glycols such as butenediol and octenediol, and diethylene glycol. , Polypropylene glycols such as dipropylene glycol, triethylene glycol, polyethylene glycol, and polytetramethylene glycol, ethylene oxide adducts of bisphenol A, and the like.
When the dibasic carboxylic acid and the glycols are reacted at an excess molar ratio of carboxylic acid, a polyester having a free carboxyl group at the molecular end can be obtained.

When these dibasic carboxylic acid compounds are used, they may be used alone or in combination of two or more. Dibasic carboxylic acid compound
(d) is generally used in a proportion of 1 mol or less, preferably 0.5 mol or less, relative to 1 mol of the amine (a).

Among the alicyclic compounds (e), the alicyclic amine having at least one active hydrogen usually has 5 ring carbon atoms.
A compound having at least about 12 alicyclic rings, preferably a cyclohexane ring, and at least one primary or secondary amino group, wherein the amino group is directly bonded to the alicyclic ring. Or may be indirectly bonded to the alicyclic ring via a linking group such as alkylene.
Specific examples of the alicyclic amine having at least one active hydrogen include cyclohexylamine, dicyclohexylamine, N-methylcyclohexylamine, 1,3- or 1,4-diaminocyclohexane, 4,4'-diamino-3, 3'-dimethyldicyclohexylmethane, 4,
4'-diamino-3,3'-dimethylbicyclohexane, isophoronediamine, 1,3-, 1,2- or 1,
4-bis (aminomethyl) cyclohexane, N-aminopropylcyclohexylamine, 1,5- or 2,6-
Bis (aminomethyl) octahydro-4,7-methanoindene, 2,2-bis (4-aminocyclohexyl)
Propane, bis (4-aminocyclohexyl) methane, 4,4'-oxybis (cyclohexylamine),
4,4'-sulfone bis (cyclohexylamine),
1,3,5-triaminocyclohexane, 2,4'- or 4,4'-diamino-3,3 ', 5,5'-tetramethyldicyclohexylmethane, menthanediamine, N-
Methyl-1,3-diaminocyclohexane, N, N-dimethyl-1,3-diaminocyclohexane, 3-N-methylamino-3,5,5-trimethylcyclohexylamine, N, N-dimethylbis (4-aminocyclohexyl) ) Methane and the like. When these alicyclic amines are used, they can be used alone or in combination of two or more.

The alicyclic epoxy compound of the alicyclic compound (e) is usually an alicyclic ring having about 5 to 12 ring carbon atoms, preferably an epoxy group directly or indirectly bonded to a cyclohexane ring. A compound, where indirect means that a group having an epoxy group, such as a glycidyl group, is attached to the alicyclic ring. Specific examples of the alicyclic epoxy compound include cyclohexene oxide, vinylcyclohexene dioxide, bis (3,4-epoxycyclohexyl) adipate, 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate, 3- (3 , 4-epoxycyclohexyl)-
8,9-Epoxy-2,4-dioxaspiro [5.5]
Undecane, diglycidyl hexahydrophthalate, 2,2-bis (4-glycidyloxycyclohexyl) propane and the like can be mentioned. Also when these alicyclic epoxy compounds are used, they can be used alone or in combination of two or more kinds.

As the alicyclic compound (e), alicyclic amine and alicyclic epoxy compound may be used in combination. The alicyclic compound (e) is based on 1 mol of the amine (a),
Generally, it is used in a proportion of 1 mol or less, preferably 0.5 mol or less.

The water-soluble resin (III) in the present invention is obtained by reacting the above-mentioned three components of the amine (a), the urea (b) and the compound (c), or optionally other components. , For example dibasic carboxylic acid compounds (d) and /
Alternatively, it can be obtained by reacting an alicyclic compound (e).

A water-soluble resin suitable for use in the present invention (II
I) is, for example, amine (a), ureas (b), compound (c)
, And, if desired, by reacting the alicyclic compound (e). The order of reaction of each component is arbitrary and is not particularly limited. For example, amine (a) and ureas (b) are subjected to deammonification or deamine reaction, and then compound (c) is reacted. Aspects can be adopted. When the alicyclic compound (e) is used, if desired, one or more alicyclic compounds (e) may be reacted during the reaction and / or the reaction.

In the reaction (1), the ureas (b) may be charged all at once to react, or a part of the ureas (b) may be initially charged and reacted with the amine (a), It is also possible to employ a two-step reaction in which the remaining ureas (b) are added to carry out the deammonification or deamine reaction. When an aldehyde is used as the compound (c) in the reaction (1), it is preferable to carry out the reaction under acidic conditions or to carry out the reaction once under alkaline conditions and then carry out the reaction under acidic conditions. On the other hand, when epihalohydrins and / or α, γ-dihalo-β-hydrins are used as the compound (c), it is preferable to carry out the reaction in a weakly acidic or alkaline manner, for example, at a pH of 5 or more, and further in a range of 6 to 9. .

Another water-soluble resin (III) suitable for use in the present invention is amine (a), urea (b), compound (c).
It can be obtained by reacting a dibasic carboxylic acid compound (d) and, if desired, an alicyclic compound (e). Also in this case, the order of reaction of each component is arbitrary and is not particularly limited, but for example, amine (a), urea (b) and dibasic carboxylic acid compound (d) may be used in any order. It is possible to adopt a mode in which a polyamide polyurea is produced by subjecting it to a deammonification or deamine reaction and a dehydration condensation reaction, and then reacting the compound (c). When the alicyclic compound (e) is used, if desired, the alicyclic compound (e)
It suffices to react one species or two or more species.

Also in the reaction in this case, ureas
(b) can be charged all at once to react, and a portion of the ureas (b) can be charged first to carry out the deammonification or deamine reaction, and the remaining ureas (b) can be removed at a later stage. In addition, it is also possible to employ a two-step reaction in which deammonification or deamine reaction is performed again. For example, amine (a)
And dibasic carboxylic acid compound (d) are dehydrated and condensed, and then urea (b) is added to carry out deammonia or deamine reaction.A part of urea (b) is removed from amine (a). After the ammonia or deamine reaction, the dibasic carboxylic acid compound (d) is dehydrated and condensed, and the remaining ureas (b) are further added to carry out the deammonification or deamine reaction, the amine (a) and the diamine. Basic carboxylic acid compound (d), urea
A method in which a part of (b) is added to carry out dehydration condensation and deammonification or deamine reaction, and the remaining ureas (b) are added to carry out deammonification or deamine reaction can be employed. Also in the reaction, when aldehydes are used as the compound (c), it is preferable to carry out the reaction under acidic conditions, or to carry out the reaction once under alkaline conditions and then carry out the reaction under acidic conditions. On the other hand, when epihalohydrins and / or α, γ-dihalo-β-hydrins are used as the compound (c), they are weakly acidic or alkaline, for example, p
It is preferable to carry out the reaction at H5 or higher, and further in the range of pH 6-9.

In the water-soluble resin (III) used in the present invention, the number of moles of amino groups consumed as a result of the reaction between the amine (a) and the ureas (b) depends on the urea (b) used in the reaction. The reaction was performed so as to exceed the number of moles. Thus, the amine (a)
Since it is necessary to carry out the reaction so as to consume a large amount of amino groups therein, at least a part of the deammonification or deamine reaction is carried out at an initial stage and under tight conditions such as relatively high reaction temperature and / or relatively high reaction temperature. It is preferable to carry out a long reaction time. The number of moles of amino groups consumed by the reaction can be quantified by a generally known analytical method, and for example,
A method for direct quantification by measuring the amine value of unreacted primary and secondary amino groups, or quantification of ammonia or amine desorbed from ureas (b) by liquid chromatography or titration. Therefore, a method of indirectly quantifying can be adopted.

The paper coating composition of the present invention contains the pigment (I), the aqueous binder (II) and the water-soluble resin (III) described above. This composition is generally prepared in the form of a coating liquid containing water, and exhibits excellent effects particularly when the coating liquid has a solid content concentration of more than 60% by weight. The solid content concentration in the coating composition is preferably more than 60% by weight and up to 75% by weight.

The composition ratio of the pigment (I) and the aqueous binder (II) is determined according to the application and purpose, and is not particularly different from the composition generally adopted in the art. The preferable composition ratio of both is about 5 to 200 parts by weight, and more preferably about 10 to 50 parts by weight of the aqueous binder (II) per 100 parts by weight of the pigment (I). The water-soluble resin (III) is preferably added in an amount of about 0.05 to 5 parts by weight as a solid content, and more preferably about 0.1 to 2 parts by weight, based on 100 parts by weight of the pigment (I). preferable. Water-soluble resin (III)
Is generally added and mixed when the coating composition is prepared, but an embodiment in which it is added and mixed with the pigment slurry or the aqueous binder in advance and this is mixed with the remaining components may be adopted.

Other components of the paper coating composition of the present invention include, for example, a dispersant, a viscosity / fluidity modifier, an antifoaming agent, a preservative, a lubricant, a water retention agent, and a dye / colored pigment. Such colorants and the like can be blended as necessary.

The coating composition for paper of the present invention is a conventionally known method, for example, a method using various known coaters such as a blade coater, an air knife coater, a bar coater, a size press coater, a gate roll coater and a cast coater. Is applied to the paper substrate. Thereafter, necessary drying is performed, and if necessary, a smoothing treatment is performed with a super calender or the like, whereby a coated paper can be manufactured.

Thus, according to the present invention, a coating composition containing a large amount of calcium carbonate as a pigment and having a high solid content concentration can be prepared, and by using it, a coated paper showing improved performance can be obtained. .

[0046]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. In the examples,% and parts indicating the content or the addition amount are based on weight unless otherwise specified. Also viscosity and pH
Is a value measured at 25 ° C. First, a synthesis example of the water-soluble resin according to the present invention will be shown.

Synthesis Example 1 A four-necked flask equipped with a thermometer, a reflux condenser and a stir bar was charged with 103.2 g (1 mol) of diethylenetriamine and 30.0 g (0.5 mol) of urea, and the internal temperature was adjusted to 130- 150
Deammonification reaction was carried out by heating at ℃ for 3 hours. The contents were diluted with water and further added with urea 10.2 g (2 mol) and 3
Charged 7% formalin 48.7g (0.6mol), 70%
Adjust the pH of the system to 4 to 5 with sulfuric acid, and
Allowed to react for hours. The amount of amino groups in the diethylenetriamine consumed during the reaction was quantified by titrating the ammonia generated in these two reactions.
Mole. Thereafter, the pH was adjusted to 6.5 with a caustic soda aqueous solution, and water was further added to adjust the concentration to 60% to obtain 351 g of a water-soluble resin aqueous solution having a viscosity of 120 cps.

Synthesis Example 2 146.2 g (1 mol) of triethylenetetramine and 120.1 g (2 mol) of urea were charged in the same vessel as used in Synthesis Example 1 and heated at an internal temperature of 130 to 150 ° C. for 5 hours. Then, a deammonification reaction was performed. Then dilute the contents with water,
Further, 32.5 g (0.4 mol) of 37% formalin was charged, the pH of the system was adjusted to 4 to 5 with 70% sulfuric acid, and then the reaction was carried out at an internal temperature of 70 ° C. for 4 hours. When the amount of amino groups in triethylenetetramine consumed during the reaction was quantified by titrating the ammonia generated in these two reactions, the total amount was 3.9 mol. After that, adjust the pH to 6.5 with an aqueous solution of caustic soda, further add water to adjust the concentration to 60%, and add 339.6 to the aqueous solution of water-soluble resin with a viscosity of 250 cps.
g was obtained.

Synthesis Example 3 146.2 g (1 mol) of triethylenetetramine and 60.1 g (1 mol) of urea were placed in the same container used in Synthesis Example 1.
Was charged and heated at an internal temperature of 140 to 150 ° C. for 3 hours to carry out a deammonification reaction. After that, further 120.1g of urea
(2 mol) was charged and the internal temperature was heated at 110 to 120 ° C. for 2 hours to carry out a deammonification reaction. The content was diluted with water, further charged with 64.9 g (0.8 mol) of 37% formalin, adjusted the system pH to 4 to 5 with 70% sulfuric acid, and then reacted at an internal temperature of 70 ° C. for 4 hours. . The amount of amino groups in triethylenetetramine consumed during the reaction was quantified by titrating the ammonia generated in these three reactions, and the total was 4.0 mol. After that, adjust the pH to 6.5 with an aqueous solution of caustic soda, and add water to adjust the concentration to 60%.
Adjusted to a value of 450 cps and the water-soluble resin aqueous solution 450 cps
g was obtained.

Synthesis Example 4 The same container used in Synthesis Example 1 was charged with 146.2 g (1 mol) of triethylenetetramine and 180.2 g (3 mol) of urea and heated at an internal temperature of 130 to 150 ° C. for 2 hours. Then, a deammonification reaction was performed. Then dilute the contents with water,
Further, 73.0 g (0.9 mol) of 37% formalin was charged, the pH of the system was adjusted to 4 to 5 with 70% sulfuric acid, and then the reaction was carried out at an internal temperature of 70 ° C. for 4 hours. When the amount of amino groups in triethylenetetramine consumed during the reaction was quantified by titrating the ammonia generated in these two reactions, the total amount was 3.9 mol. After that, adjust the pH to 6.5 with an aqueous solution of caustic soda, and further add water to adjust the concentration to 60%. 450 g of a water-soluble resin aqueous solution having a viscosity of 270 cps
I got

Synthesis Example 5 103.2 g (1 mol) of diethylenetriamine and 150.2 g (2.5 mol) of urea were charged in the same container as used in Synthesis Example 1 and heated at an internal temperature of 130 to 150 ° C. for 2 hours. Then, a deammonification reaction was performed. Then dilute the contents with water,
Further, 48.7 g (0.6 mol) of 37% formalin was charged, the system pH was adjusted to 4 to 5 with 70% sulfuric acid, and then the reaction was carried out at an internal temperature of 70 ° C. for 4 hours. The amount of the amino groups in the diethylenetriamine consumed during the reaction was quantified by titrating the ammonia generated in these two reactions, and the total was 2.9 mol. After that, adjust the pH to 6.5 with an aqueous solution of caustic soda, further add water to adjust the concentration to 60%, and add 355 g of an aqueous solution of water-soluble resin having a viscosity of 120 cps.
I got

Synthesis Example 6 146.2 g (1 mol) of triethylenetetramine and 240.3 g (4 mol) of urea were charged in the same container as used in Synthesis Example 1 and heated at an internal temperature of 110 to 120 ° C. for 4 hours. Then, a deammonification reaction was performed. Then dilute the contents with water,
Further, 32.5 g (0.4 mol) of 37% formalin was charged, the pH of the system was adjusted to 4 to 5 with 70% sulfuric acid, and then the reaction was carried out at an internal temperature of 70 ° C. for 4 hours. Ammonia generated in these two reactions was titrated to quantify the amino group in triethylenetetramine consumed during the reaction, and the total amount was 3.5 mol. After that, adjust the pH to 6.5 with an aqueous solution of caustic soda, further add water to adjust the concentration to 60%, and add a water-soluble resin aqueous solution having a viscosity of 150 cps to 587.5.
g was obtained.

Synthesis Example 7 Pentaethylenehexamine (232.4 g, 1 mol) and urea (360.4 g, 6 mol) were charged in the same vessel as used in Synthesis example 1, and heated at an internal temperature of 110 to 120 ° C. for 6 hours. Then, a deammonification reaction was performed. Then dilute the contents with water,
Further, 48.7 g (0.6 mol) of 37% formalin was charged, the system pH was adjusted to 4 to 5 with 70% sulfuric acid, and then the reaction was carried out at an internal temperature of 70 ° C. for 4 hours. Ammonia generated in these two reactions was titrated to quantify the amino groups in pentaethylenehexamine consumed during the reaction, and the total was 5.5 mol. After that, adjust the pH to 6.5 with an aqueous solution of caustic soda, and add water to adjust the concentration to 60%.
Adjusted to a viscosity of 250 cps water-soluble resin aqueous solution 865
g was obtained.

Next, an example in which a coating composition for paper was prepared and evaluated using the resin aqueous solutions obtained in Synthesis Examples 1 to 3, 6 and 7 will be shown.

Examples 1 to 3 and Comparative Examples 1 and 2 The master colors shown in Table 1 were used, and Synthesis Examples 1 to
Each of the resin aqueous solutions obtained in 3, 6, and 7 was added so that the solid content in the resin aqueous solution was 0.8 parts per 100 parts of the pigment in the master color.

[0056]

[Table 1] ^{* 1} Ultra White 90: Clay made by Engel Hard Minerals, Inc. ^{* 2} Carbital 90: Calcium carbonate made by Fuji Kaolin Co., Ltd. ^{* 3} Sumirez Resin DS-10: Polyacrylic acid pigment dispersant made by Sumitomo Chemical Co., Ltd. ^{* 4} SN-307: Styrene-butadiene latex manufactured by Sumitomo Dow Co., Ltd. ^{* 5} MS-4600: Phosphoesterified starch manufactured by Nippon Shokubai Co., Ltd. ^{* 6} Blending ratio: Percentage by solid content

Each composition had a total solids content of 65%,
The pH was adjusted to about 9 with water and 10% aqueous sodium hydroxide solution, respectively. The physical properties of the obtained coating compositions were measured by the following methods, and the results are shown in Table 2.

(1) pH glass electrode type hydrogen ion concentration meter [Toa Denpa Kogyo Co., Ltd.]
The pH of the coating composition immediately after preparation was measured at 25 ° C.

(2) Viscosity Using a B type viscometer [BL type manufactured by Tokyo Keiki Co., Ltd.], 60
The viscosity of the coating composition immediately after preparation was measured at 25 rpm and rpm.

Each coating composition obtained as described above was applied to one surface of a high-quality paper having a basis weight of 80 g / m ² using a wire rod so that the coating amount was 14 g / m ^2. Was applied to. Immediately after the application, hot-air drying was performed at 120 ° C for 30 seconds, then humidity was adjusted for 16 hours at a temperature of 20 ° C and a relative humidity of 65%.
Super-calendering was performed once to obtain a coated paper. The coated paper thus obtained was subjected to tests for water resistance and ink acceptability, and the test results are shown in Table 2. The test method is as follows.

(3) Water resistance: Wet pick method (WP method) Using an RI tester (manufactured by Akira Seisakusho Co., Ltd.), the coated surface was wetted with a water supply roll and then printed, and the peeled state was observed with the naked eye. It was judged. The judgment criteria were as follows. Water resistance (poor) 1-5 (excellent)

(4) Ink acceptability (4-1) Method A Using an RI tester, the coated surface was wetted with a water supply roll and then printed, and the acceptability of the ink was visually observed and judged. The judgment criteria were as follows. Ink acceptability (poor) 1-5 (excellent)

(4-2) Method B Using an RI tester, a small amount of water was poured into a slight gap between the rubber roll and the kneading roll, printing was performed, and the ink acceptability was visually observed and judged. . The judgment criteria were as follows. Ink acceptability (poor) 1-5 (excellent)

[0064]

[Table 2]

[0065]

EFFECT OF THE INVENTION The paper coating composition of the present invention contains a relatively large amount of relatively inexpensive calcium carbonate and has a high solid content concentration, but has a low viscosity and excellent coating suitability. There are no streaks during coating. The coated paper obtained from this composition has various excellent and effective properties such as excellent ink acceptability and water resistance.

Claims (6)

[Claims] 1. A pigment in which at least 40% by weight of the total pigment is calcium carbonate, (II) an aqueous binder, and (III) at least (a) an amine selected from alkylenediamines and polyalkylenepolyamines, (b) 0.5 to 0.9 mol of urea relative to a total of 1 mol of primary and secondary amino groups in amine (a), and (c) aldehydes, epihalohydrins and α, γ-dihalo-β- The number of moles of the amino group consumed as a result of the reaction between the amine (a) and the urea (b) in the three components of the compound selected from hydrins exceeds the number of moles of the urea (b) used in the reaction. A coating composition for paper having a high solid content, which comprises a water-soluble resin obtained by such a reaction and has a solid content of more than 60% by weight. 2. The water-soluble resin (III) is (a) the amine,
The composition according to claim 1, which is obtained by reacting (b) the urea, (c) the compound, and (d) a dibasic carboxylic acid compound. 3. The composition according to claim 2, wherein the dibasic carboxylic acid compound (d) is a free acid, an ester or an acid anhydride. 4. The water-soluble resin (III) is (a) the amine,
A compound obtained by reacting (b) the urea, (c) the compound, and (e) an alicyclic compound selected from alicyclic amine and at least one alicyclic epoxy compound having active hydrogen. The composition as described. 5. The resin component (III) comprises (a) the amine, (b)
The urea, (c) the compound, (d) a dibasic carboxylic acid compound, and (e) an alicyclic compound selected from alicyclic amine and alicyclic epoxy compounds having at least one active hydrogen The composition according to claim 1, which is obtained by reacting. 6. The composition according to claim 1, which contains 5 to 200 parts by weight of the aqueous binder (II) and 0.05 to 5 parts by weight of the water-soluble resin (III) per 100 parts by weight of the pigment (I). The composition according to claim 1.