JP2003252985A - Resin for paper coating - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin for paper coating which gives a coated paper excellent in ink receptivity and water resistance substantially without a crosslinkable compound such as formalin. <P>SOLUTION: The resin for paper coating is obtained by reacting polyamines, urea compounds, aromatic polycarboxylic acids as essential components and a crosslinkable compound as an optional component together, where the contents of urea compounds, the aromatic polycarboxylic acids and the crosslinkable compound are 0.05-1 mole, 0.01-0.5 mole and at most 0.01 mole, respectively, each based on 1 mole of the total nitrogen atoms contained in a primary amino group and a secondary amino group in the polyamines. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a paper coating resin obtained by reacting polyamines, ureas and aromatic polycarboxylic acids, and a paper coating resin composition containing the resin as an active ingredient. .

[0002]

PRIOR ART AND PROBLEM TO BE SOLVED BY THE INVENTION Conventionally, a paper coating resin composition containing a paper coating resin comprising a crosslinkable compound such as polyamines, ureas, aromatic polycarboxylic acids and formalin. It has been reported that the product is excellent in ink acceptability and water resistance (for example, JP-A-2-221498). Recently, there has been a demand for a paper coating resin composition that reduces formalin, which has been designated as a voluntary emission control substance in the paper manufacturing industry, but a paper coating resin obtained by reducing cross-linking compounds such as formalin. When the resin composition for paper coating containing the above is used, there is a problem that the ink acceptability or water resistance of the obtained coated paper is deteriorated.

[0003]

Under these circumstances, the inventors of the present invention have made extensive studies and found that a resin for paper coating containing a specific amount of each of polyamines, urea compounds and aromatic polycarboxylic acids was found. The present invention has been completed by finding that it can be used as an active ingredient of a resin composition for paper coating which gives a coated paper having excellent ink acceptability and water resistance even if it does not substantially contain a crosslinkable compound. did.

That is, the present invention provides a paper coating resin obtained by reacting polyamines, ureas, and aromatic polycarboxylic acids as essential components, and a crosslinkable compound as an optional component. The content of urea is 0.05 to 1 mol and the content of aromatic polycarboxylic acid is 0.01 to 0 with respect to a total of 1 mol of nitrogen atoms contained in the primary amino group and secondary amino group. 0.5 mol, and the content of the crosslinkable compound is 0.01 mol or less, a resin for paper coating;

Α, β-unsaturated carbonyl compounds, α, β
-Essentially at least one component selected from the group consisting of unsaturated nitrile compounds, α-halocarboxylic acids, halogenated hydrocarbons and alkylsulfates, polyamines, ureas, and aromatic polycarboxylic acids In a paper coating resin obtained by reacting a crosslinkable compound as a component with an optional component, urea is added to 1 mol of the total nitrogen atoms contained in the primary amino group and secondary amino group of the polyamines. Of 0.05 to 1 mol, the content of aromatic polycarboxylic acids is 0.01 to 0.5 mol, and the content of the crosslinkable compound is 0.01 mol or less. Resin for paper coating;

A resin composition for paper coating characterized by containing a pigment, an aqueous binder and the resin for paper coating; and a coating obtained by coating the paper with the resin composition for paper coating. It is craft paper.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The polyamines used in the present invention are compounds containing at least two primary or secondary amino groups which are not adjacent to a carbonyl group in the molecule, and include, for example, ethylenediamine, propylenediamine, hexamethylenediamine and the like having 1 carbon atom. Alkylenediamine containing about 10 to 10 alkylene groups; diethylenetriamine, triethylenetetramine, pentaethylenehexamine, tetraethylenepentamine, iminobispropylamine, 3-azahexane-1,6-diamine, 4,7-diazadecane-
Polyalkylene polyamines such as 1,10-diamines;
Examples thereof include alicyclic polyamines such as isophoronediamine and bis (aminomethyl) cyclohexane; and heterocyclic polyamines.

Here, the heterocyclic polyamine is usually a polyamine having an alicyclic heterocycle containing at least one hetero atom such as nitrogen atom, oxygen atom and sulfur atom, and a primary or secondary amino group. And the nitrogen atom contained in the heterocycle of the heterocyclic polyamine may be a primary or secondary amino group. Specifically, heterocyclic polyamines containing at least two secondary amino groups in a heterocycle such as piperazine and homopiperazine; N-aminoethylpiperazine, N-aminopropylpiperazine, 1,4-bis (aminopropyl) Heterocyclic polyamines containing aminoalkyl groups such as piperazine can be mentioned.

As the polyamines, two or more kinds of polyamines may be used in combination. Among them, polyalkylene polyamines and heterocyclic polyamines are preferable as the polyamines.

The sum of nitrogen atoms contained in the primary amino group and the secondary amino group of the polyamines used in the present invention is represented by the following formula (1) H ₂ N- (C ₂ H ₄ ) -NH A specific example of triethylenetetramine represented by-(C ₂ H ₄ ) -NH- (C ₂ H ₄ ) -NH ₂ (1) is that one molecule of triethylenetetramine has the formula (1). Since there are two primary amino groups and two secondary amino groups, the total number of nitrogen atoms contained in the primary amino group and the secondary amino group is four. Similarly, a total of 1 mol of nitrogen atoms contained in the primary amino group and the secondary amino group of the polyamines means 1/4 mol, that is, 0.25 mol of triethylenetetramine.

Examples of ureas used in the present invention include urea, methylurea, dimethylurea and thiourea. Further, as urea, two or more kinds of urea may be used in combination. Among them, urea is preferable as the urea.

The aromatic polycarboxylic acid of the present invention includes
For example, benzenedicarboxylic acid such as phthalic acid, isophthalic acid and terephthalic acid; dicarboxylic acid having a plurality of aromatics such as naphthalene dicarboxylic acid, biphenyl dicarboxylic acid and phenanthrene dicarboxylic acid; trimellitic acid,
Examples thereof include aromatic polycarboxylic acids having 3 or more carboxyl groups in the molecule, such as naphthalenetricarboxylic acid and pyromellitic acid.

The aromatic polycarboxylic acids include, for example, esters of aromatic polycarboxylic acids; phthalic anhydride,
Examples thereof include anhydrides of aromatic polycarboxylic acids such as trimellitic anhydride and pyromellitic dianhydride. Examples of the ester include mono- or diesters of lower alcohols such as methanol and ethanol and aromatic polycarboxylic acids; mono- or diesters of glycols and aromatic polycarboxylic acids. Examples of the glycol 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; diethylene glycol and dipropylene glycol. , Polyethylene glycols such as triethylene glycol, polyethylene glycol and polytetramethylene glycol; and ethylene oxide adducts of bisphenol A.

As the aromatic polycarboxylic acids of the present invention, two or more kinds of aromatic polycarboxylic acids may be used in combination. As aromatic polycarboxylic acids,
Among them, benzenedicarboxylic acids are preferable.

The paper coating resin of the present invention contains urea in an amount of 0.05-0.5 mol based on 1 mol of the total of nitrogen atoms contained in the primary amino group and secondary amino group of the polyamines used in the present invention.
A resin for paper coating obtained by reacting 1 mol and 0.01 to 0.5 mol of an aromatic polycarboxylic acid, and preferably,
About 0.1 mol of ureas and about 0.1 mol of aromatic polycarboxylic acids are used per 1 mol of the total nitrogen atoms contained in the primary amino group and secondary amino group of the polyamines used in the present invention. It is a resin for paper coating obtained by reacting about 04 to 0.5 mol. Among them, the paper coating resin is preferably a resin obtained by substantially reacting only polyamines, ureas and aromatic polycarboxylic acids.

As an optional component containing the paper coating resin of the present invention, an α, β-unsaturated carbonyl compound, α, β-
At least one compound selected from unsaturated nitrile compounds, α-halocarboxylic acids, and alkylating agents (hereinafter,
Component (a)) may be used. Where α, β-
Examples of unsaturated carbonyl compounds include α, β-unsaturated carboxylic acids such as acrylic acid, crotonic acid, isocrotonic acid, methacrylic acid, sorbic acid, and cinnamic acid; methyl group, ethyl group, butyl group, and α, β. -Esters with unsaturated carboxylic acids; α, β-unsaturated aldehydes such as acrolein, crotonaldehyde, cinnamaldehyde; methyl vinyl ketone, mesityl oxide, benzalacetone, dibenzalacetone, benzalacetophenone, diphenone, etc. Examples include α, β-unsaturated ketones; α, β-unsaturated polycarboxylic acids such as fumaric acid and maleic acid, and esters thereof; α, β-unsaturated carboxylic acid anhydrides such as maleic anhydride.

As the α, β-unsaturated nitrile compound,
Examples thereof include acrylonitrile and methacrylonitrile. Examples of α-halocarboxylic acids include:
Α-halocarboxylic acids such as chloroacetic acid, bromoacetic acid, dichloroacetic acid, dibromoacetic acid, trichloroacetic acid, α-chloropropionic acid, α-chlorobutyric acid, α-bromoisovaleric acid; methyl group, ethyl group, butyl group and the like and α- Esters with halocarboxylic acids; salts of alkali (earth) metals such as potassium, sodium and calcium with α-halocarboxylic acids and the like can be mentioned.

Examples of the alkylating agent include halogenated methyl chloride, methyl bromide, methyl iodide, ethyl chloride, ethyl bromide, propyl iodide, isopropyl iodide, butyl bromide, benzyl chloride, benzyl bromide and the like. Hydrocarbons; halogenated acetic acid esters such as methyl chloroacetate, ethyl chloroacetate, methyl bromoacetate and ethyl bromoacetate; epoxy compounds containing no halogen atom such as ethylene oxide and propylene oxide; alkyls such as dimethyl sulfate and diethyl sulfate Examples thereof include sulfuric acid esters.

As the component (a), among others, α, β-unsaturated carboxylic acid, α, β-unsaturated carboxylic acid ester,
α-Chlorocarboxylic acids, halogenated hydrocarbons and alkyl sulfates are preferable, and acrylic acid, chloroacetic acid and alkyl sulfates are particularly preferable. In the paper coating resin of the present invention, the amount of the optional component (a) used is usually about 1.5 mol or less, preferably 1 mol or less, and particularly preferably 0 mol, relative to 1 mol of the polyamines. It is not more than 5 mol.

Further, as an optional component contained in the paper coating resin of the present invention, it is selected from the group consisting of formaldehyde, polyaldehyde, epihalohydrin, α, ω-dihalo-β-hydrin, polyepoxy compound and polyisocyanate compound. 0.0 at least one kind of the crosslinkable compound is added to the total amount of nitrogen atoms contained in the primary amino group and the secondary amino group contained in the polyamine.
Although it may be contained as long as it is 1 mol or less, it is preferable that the crosslinking compound is not contained. In particular,
It is also preferable not to contain formaldehyde, and as a result, the amount of formaldehyde detected from the resulting aqueous solution of the paper coating resin is preferably 1000 ppm or less.

Here, examples of the polyaldehyde include alkyldialdehydes such as glyoxal, propanedial and butanedial.

Epihalohydrin is usually the following general formula (2) (In the formula, n represents an integer of about 1 to 5, and X represents a halogen atom or the like.), And specifically,
Examples thereof include n = 0 epichlorohydrin and epibromohydrin.

Α, ω-dihalo-β-hydrin is usually represented by the following general formula (3) (In the formula, m represents an integer of about 1 to 5, and Y and Z represent halogen atoms.) Specifically, α such as 1,3-dichloro-2-propanol. ，
γ-dihalo-β-hydrin and the like can be mentioned.

The polyepoxy compound is usually a compound having at least two epoxy groups in the molecule, specifically, alkylene glycol diglycidyl ethers such as ethylene glycol diglycidyl ether and propylene glycol diglycidyl ether; Polyoxyalkylene glycol diglycidyl ethers such as polyethylene glycol diglycidyl ether and polypropylene glycol diglycidyl ether; resorcin diglycidyl ether, aromatic polyvalent glycidyl ethers such as bisphenol A diglycidyl ether, vinyl cyclohexene 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)
Alicyclic diglycidyl compounds such as propane, trimethylolpropane di- or tri-glycidyl ether,
Examples thereof include polyglycidyl ethers of polyhydric alcohols such as sorbitol di-, tri-, tetra-, penta- or hexa-glycidyl ether, pentaerythritol di-, tri- or tetra-glycidyl ether.

The polyisocyanate compound usually has at least two isocyanate groups in the molecule. Specific examples thereof include alicyclic isocyanates such as isophorone diisocyanate, 3- (2-isocyanatocyclohexyl) propyl isocyanate, bis (isocyanatomethyl) cyclohexane, isopropylidene bis (cyclohexyl isocyanate), cyclohexane diisocyanate, and bicycloheptane triisocyanate. , Hexamethylene diisocyanate, trimethylhexane-1,6-diisocyanate, aliphatic isocyanates such as methyl 2,6-diisocyanatohexanoate (so-called lysine diisocyanate), tolylene diisocyanate, triphenylmethane triisocyanate, tris ( Isocyanatophenyl) thiophosphate, phenylene diisocyanate, dianisidine diisocyanate, diphenyl Aromatic isocyanates and the like, such as chromatography ether diisocyanate.

As the method for producing the resin for paper coating of the present invention, for example, (1) a method in which polyamines and ureas are deammonified and then dehydrated and / or dealcoholized with aromatic polycarboxylic acids , (2) dehydration and / or dealcoholation reaction of polyamines and aromatic polycarboxylic acids, and then deammonification reaction with ureas, (3) mixing polyamines, ureas and aromatic polycarboxylic acids Examples thereof include a method of simultaneously performing the deammonification reaction and the dehydration and / or dealcoholization reaction. The component (a) and the crosslinkable compound may be added and reacted in any reaction, or the above reaction may be carried out after reacting with polyamines in advance, or a resin for paper coating. The component (a) and the crosslinkable compound can be added and reacted after the production of.

Here, the dealcoholization reaction includes, for example, a method of stirring at about 80 to 180 ° C., preferably about 90 to 160 ° C. while distilling off the generated water and / or ammonia. Examples of the dehydration reaction include a method of stirring the reaction solution of the dehydration reaction at about 80 to 200 ° C., preferably at about 100 to 180 ° C. for about 2 to 10 hours while distilling generated water. . Of course, dehydration and dealcoholization reaction may be carried out simultaneously under the same conditions.

The thus obtained paper coating resin is adjusted, if necessary, with an acid such as a mineral acid such as phosphoric acid or sulfuric acid so as to have a pH of about neutral or more, preferably about 7 to 12. Approximately 50% non-volatile content of solution containing paper coating resin
The viscosity when adjusted to 1 is usually about 1 to 10,000 mPa · s, preferably about 2 to 5,000 mPa · s.

The paper coating composition of the present invention comprises a paper coating resin, a pigment and an aqueous binder.
Examples of the pigment include white inorganic pigments such as kaolin, talc, calcium carbonate (heavy or light), aluminum hydroxide, satin white, and titanium oxide; white pigments such as polystyrene, melamine-formaldehyde resin, and urea-formaldehyde resin. Examples include organic pigments. Two or more kinds of pigments may be used as the pigment. As the pigment, kaolin, calcium carbonate and chisan white are particularly preferable.

Examples of the aqueous binder include non-modified or modified starches such as oxidized starch and phosphate esterified starch; partially or completely saponified polyvinyl alcohol; water-soluble proteins such as casein and gelatin;
Modified celluloses such as carboxymethyl cellulose;
Styrene-butadiene-based resin (SBR latex) that may have a carboxyl group or a nitrile group; acrylonitrile-butadiene-based resin (NBR latex); chloroprene-based resin (CR latex); methylmethacrylate-butadiene-based resin (MBR latex); acrylic Acid, methacrylic acid and copolymer resins of two or more acrylic monomers selected from their esters such as methyl, ethyl and butyl, copolymer resins of acrylic monomers and vinyl acetate, copolymerization of acrylic monomers and styrene Resin; vinyl acetate resin; styrene-vinyl acetate resin,
Examples thereof include ethylene-vinyl acetate resin. You may use 2 or more types of aqueous binders as an aqueous binder.

The weight ratio of the pigment, the aqueous binder and the paper coating resin in the resin composition for paper coating of the present invention is usually about 1 to 200 parts, preferably about 100 parts by weight of the aqueous binder, relative to 100 parts of the pigment. 5 to 50 parts,
About 0.05 to 5 parts of resin for paper coating, preferably 0.1
It is about 2 parts.

The resin composition for paper coating of the present invention may contain a non-volatile substance. Here, as the non-volatile substance,
Examples thereof include inorganic salts such as ammonium chloride, sodium chloride, calcium chloride, magnesium chloride, aluminum chloride, ammonium sulfate, sodium sulfate, and ammonium phosphate; the above ureas; sugars such as glucose and fructose. Among these non-volatile substances, ureas and saccharides are preferable, and urea and imidazolidinones are particularly preferable. The weight ratio of the paper coating resin and the non-volatile substance in the paper coating resin composition is [nonvolatile content of the paper coating resin] / [non-volatile substance] = 1/9
9 to 90/10, preferably 5/95 to 7
It is about 0/30.

The non-volatile substance may be mixed, for example, by mixing the paper coating resin of the present invention with the non-volatile substance, and then mixing the pigment with the aqueous binder; after mixing the aqueous binder with the non-volatile substance. , A method of mixing a pigment and a paper coating resin; a method of mixing a pigment and a non-volatile component and then a paper coating resin and an aqueous binder; a paper coating resin, a pigment, an aqueous binder and a non-volatile component in order A method of mixing: a method of collectively mixing a resin for paper coating, a pigment, an aqueous binder, a non-volatile component, and the like.

The coating composition for paper includes, for example, a waterproofing agent,
It may contain a compounding agent such as a printability improving agent, a dispersant, a viscosity / fluidity adjusting agent, an antifoaming agent, an antiseptic, a lubricant, a water retention agent, and a coloring agent such as a dye or a colored pigment.

The resin composition for paper coating thus obtained is
For example, a blade coater, an air knife coater, a bar coater, a size press coater, a gate roll coater, a cast coater or the like is used to coat the paper, followed by necessary drying, and if necessary, smoothing treatment with a super calendar or the like. By applying, the coated paper of the present invention can be manufactured.

Here, as the paper used in the present invention,
Examples include paper made from vegetable fibers such as western paper, Japanese paper, paperboard, synthetic fiber paper made from synthetic pulp made from synthetic resin, inorganic fiber paper, and synthetic paper such as plastic paper made from synthetic resin film. To be Above all,
Paper made from vegetable fibers is preferable.

[0037]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. In the examples,% and parts are based on weight unless otherwise specified. The pH is a value measured at 25 ° C., the non-volatile content is a value measured according to JIS K 0067 4.1, and the solid content is the weight of each component excluding a solvent such as water. And the concentration means the weight ratio (%) of the solid content in the solution. According to JIS L1041-94, the amount of free formalin in the aqueous solution of the paper coating resin is 100 m when the aqueous solution of the paper coating resin is 2.5 g by the acetylacetone method.
It was determined by measuring the absorbance of the solution diluted to 1.

(Synthesis of Aqueous Solution of Paper Coating Resin) (Synthesis Example 1) 25.80 parts of pentaethylenehexamine (0.111 molar ratio, total of 0.666 of nitrogen atoms contained in primary and secondary amino groups) Molar ratio) and urea 12.
While removing ammonia generated from 01 part (0.200 mol ratio) at an internal temperature of 150 to 160 ° C. outside the system, the mixture was stirred for 5 hours. Next, 12.90 parts of pentaethylenehexamine (0.056 mol ratio, a total of 0.333 mol ratio of nitrogen atoms contained in primary and secondary amino groups) and 18.46 parts of isophthalic acid (0.111 mol ratio). ) Is added and the internal temperature is 1
The mixture was stirred at 70 to 190 ° C for 5 hours while distilling off the water, and the water
Nonvolatile matter 54.4 by adding 3.9 parts and 2.41 parts of sulfuric acid.
%, PH 8.9, and a viscosity of 159 mPa · s, an aqueous solution of a resin for paper coating was obtained. No free formalin could be detected.

(Synthesis Example 2) The amount of urea was 15.02 parts (0.250 mol ratio), and the amount of sulfuric acid added was 0.
79 parts, except that the addition amount of water is different, the same procedure as in Synthesis Example 3 is carried out to obtain a nonvolatile content of 52.2% and a pH of 7.
3, an aqueous solution of a resin for paper coating having a viscosity of 137 mPa · s was obtained. No free formalin could be detected.

(Synthesis Example 3) Pentaethylenehexamine 2
5.80 parts (0.111 mol ratio, a total of 0.666 mol ratio of nitrogen atoms contained in primary and secondary amino groups) and 15.02 parts urea (0.250 mol ratio) were added at an internal temperature of 150 to
The mixture was stirred for 5 hours while removing the ammonia generated at 160 ° C outside the system. Next, 12.90 parts of pentaethylenehexamine (0.056 mol ratio, a total of 0.333 mol ratio of nitrogen atoms contained in primary and secondary amino groups) and 18.46 parts of isophthalic acid (0.111 mol ratio). ) Was added, and the mixture was stirred for 5 hours while distilling off water at an internal temperature of 170 to 190 ° C., and after adding 40.6 parts of water, an internal temperature of 70 to 75 ° C.
Resorcin diglycidyl ether 7.30
Part (0.033 molar ratio) was added, and the internal temperature was 70 to 7
The mixture was kept warm and stirred at 5 ° C for 6 hours. Then, 22.1 parts of water was added to the mixture to give a nonvolatile content of 51.4%, a pH of 8.4, and a viscosity of 55.
An aqueous solution of paper coating resin of 8 mPa · s was obtained. No free formalin could be detected.

(Synthesis Example 4) Pentaethylenehexamine 3
8.73 parts (0.167 mole ratio, total 1 mole ratio of nitrogen atoms contained in primary and secondary amino groups) and urea 1
1.68 parts (0.194 mol ratio) with an internal temperature of 150-160
The mixture was stirred for 5 hours while removing the ammonia generated at 0 ° C outside the system. Next, 5.53 parts of isophthalic acid (0.03
3 molar ratio), 5.53 parts terephthalic acid (0.033 molar ratio) and 6.49 parts adipic acid (0.044 molar ratio)
Was added, and water was distilled off at an internal temperature of 170 to 190 ° C.
After stirring for 5 hours, 55.9 parts of water and 3.81 parts of sulfuric acid were added,
An aqueous solution of a paper coating resin having a nonvolatile content of 52.8%, a pH of 9.0 and a viscosity of 86 mPa · s was obtained. No free formalin could be detected.

(Synthesis Example 5) Triethylenetetramine 2
0.38 parts (0.139 mole ratio, total 0.557 mole ratio of nitrogen atoms contained in primary and secondary amino groups) Water 5.
9 parts and 4.20 parts (0.070 mol ratio) of urea were refluxed at an internal temperature of 90 to 110 ° C. and stirred for 5 hours while removing generated ammonia out of the system. Next, 14.40 parts of diethylenetriamine (0.140 mol ratio, a total of 0.419 mol ratio of nitrogen atoms contained in primary and secondary amino groups) and 46.3 parts of isophthalic acid (0.279 mol ratio) were added. The mixture was added and stirred at an internal temperature of 170 to 190 ° C for 5 hours while distilling off water and ammonia.
An aqueous solution of a Pa · s paper coating resin was obtained. No free formalin could be detected.

Synthesis Example 6 The amount of urea was 6.96 parts (0.
116 mol ratio) and the same as Synthesis Example 6 except that the amount of water added was different, and the nonvolatile content was 64.4%.
An aqueous solution of a paper coating resin having a pH of 8.7 and a viscosity of 978 mPa · s was obtained. No free formalin could be detected.

(Synthesis Example 7) Triethylenetetramine 2
3.84 parts (0.163 molar ratio, total of nitrogen atoms contained in primary and secondary amino groups 0.652 molar ratio) water 7.
9 parts of urea and 10.51 parts of urea (0.175 mol ratio) were refluxed at an internal temperature of 110 to 115 ° C., and stirring was performed for 5 hours while removing generated ammonia out of the system. Next, 12.02 parts of diethylenetriamine (0.117 molar ratio,
The total number of nitrogen atoms contained in the primary and secondary amino groups is 0.
350 mole ratio) and 38.69 parts of isophthalic acid (0.
233 mol ratio), and stirred for 5 hours while distilling off water and ammonia at an internal temperature of 170 to 190 ° C., and water 43.
By adding 4 parts, an aqueous solution of a resin for paper coating having a nonvolatile content of 64.1%, a pH of 8.9 and a viscosity of 484 mPa · s was obtained. No free formalin could be detected.

(Synthesis Example 8) Triethylenetetramine 2
3.84 parts (0.163 molar ratio, total 0.652 molar ratio of nitrogen atoms contained in primary and secondary amino groups) and 10.5 parts water while maintaining an internal temperature of 65 to 75 ° C. epichlorohydride After 7.55 parts of phosphorus (0.082 mol ratio) was added dropwise, the mixture was kept warm and stirred for 4 hours. Thereafter, 9.80 parts of urea (0.163 mol ratio) was added, and while keeping water and ammonia distilled off, the temperature was kept at an internal temperature of 150 to 160 ° C. for 12 hours,
It was stirred. Next, 11.92 parts of triethylenetetramine (0.082 molar ratio, a total of 0.326 molar ratio of nitrogen atoms contained in primary and secondary amino groups) and 27.14 parts of isophthalic acid (0.163 molar ratio). ) Is added and the internal temperature is 1
Stir for 8 hours while distilling off water at 60 to 180 ° C.
7.0 parts and 4.40 parts of 80% acrylic acid (0.049
(Molar ratio), and the mixture is kept at 65 to 75 ° C. for 1 hour and stirred to have a nonvolatile content of 63.5%, a pH of 6.8, and a viscosity of 407 mPas.
An aqueous solution of the resin for paper coating of s was obtained. No free formalin could be detected.

(Synthesis Example 9) Triethylenetetramine 3
6.56 parts (0.250 molar ratio, total 1 molar ratio of nitrogen atoms contained in primary and secondary amino groups) 10.6 parts water and 7.51 parts urea (0.125 molar ratio) were used as internal temperature. 110
The mixture was stirred at ~ 115 ° C under reflux for 5 hours while removing generated ammonia out of the system. Next, 25.75 parts of diethylenetriamine (0.250 mole ratio, a total of 0.750 mole ratio of nitrogen atoms contained in primary and secondary amino groups) and 97.03 parts of dimethyl isophthalate (0.
500 mol ratio), water at an internal temperature of 150 to 160 ° C.,
The mixture was stirred for 5 hours while distilling off methanol and ammonia, and 160.2 parts of water and 96.2 parts of urea were added and thoroughly mixed with stirring to contain urea and a resin for paper coating as nonvolatile components, and a concentration of 60%. , PH 9.1, viscosity 46.0 mPa ・
An aqueous solution of s was obtained. No free formalin could be detected.

(Synthesis Example 10) Triethylenetetramine 3
6.56 parts (0.250 molar ratio, total 1 molar ratio of nitrogen atoms contained in primary and secondary amino groups) 10.6 parts water and 7.51 parts urea (0.125 molar ratio) were used as internal temperature. 110
The mixture was stirred at ~ 115 ° C under reflux for 5 hours while removing generated ammonia out of the system. Next, 25.75 parts of diethylenetriamine (0.250 molar ratio, a total of 0.750 molar ratio of nitrogen atoms contained in primary and secondary amino groups) and 83.09 parts of isophthalic acid (0.500 molar ratio) were added. The mixture was added and stirred at an internal temperature of 180 to 200 ° C. for 5 hours while distilling off water and ammonia. 166.1 parts of water and 99.5 parts of urea were added and sufficiently stirred and mixed. 60% concentration containing engineering resin, p
An aqueous solution having H9.1 and a viscosity of 55.5 mPa · s was obtained. No free formalin could be detected.

COMPARATIVE SYNTHESIS EXAMPLE 1 Triethylenetetramine 36. was placed in a container equipped with a thermometer, a reflux condenser and a stirring rod.
56 parts (0.250 molar ratio, total 1 molar ratio of nitrogen atoms contained in primary and secondary amino groups) and urea 7.50
Parts (0.125 molar ratio) are mixed to obtain an internal temperature of 140 to 160
The mixture was stirred for 5 hours while removing the ammonia generated at ℃ outside the system. Next, the internal temperature was lowered to 120 ° C., 18.28 parts (0.125 mol ratio) of adipic acid was added, and the internal temperature was adjusted to 15
Stir for 5 hours while distilling off water at 0-160 ° C, then
The inner temperature was lowered to 130 ° C, and 30.02 parts of urea (0.500
(Molar ratio) was mixed and the generated ammonia was distilled off at an internal temperature of 120 to 140 ° C., and the mixture was stirred for 3 hours. afterwards,
67.3 parts of water and 14.08 parts of 37% formalin (0.
174 molar ratio) and pH was adjusted to 5.0 with sulfuric acid, and then stirred at an internal temperature of 70 ° C. for 4 hours to give a nonvolatile content of 50.2%,
An aqueous solution of a paper coating resin having a pH of 6.2 and a viscosity of 75 mPa · s was obtained. Free formalin was 1170 ppm.

(Comparative Synthesis Example 2) Diethylenetriamine 3
4.39 parts (0.333 mole ratio, total 1 mole ratio of nitrogen atoms contained in primary and secondary amino groups), water 23.6 parts and urea 60.11 parts (1.00 mole ratio) are mixed. Then, the mixture was stirred for 12 hours under an internal temperature of 90 to 110 ° C under reflux distillation while removing the generated ammonia out of the system. Next, the internal temperature was lowered to 80 ° C, and 37.% formalin 27.05 parts (0.3
33 mol ratio) and 10.5 parts of water were added, and the internal temperature was 95-1.
The mixture was stirred at 05 ° C for 1 hour. Then, after adjusting the pH to 4.0 with sulfuric acid, the mixture was stirred at an internal temperature of 70 ° C. for 4 hours, and the nonvolatile content
An aqueous solution of a resin for paper coating having 1.0%, pH 6.4 and a viscosity of 60 mPa · s was obtained. Free formalin was 2285 ppm.

(Production Example of Resin Composition for Paper Coating) <Examples 1 to 10 and Comparative Examples 1 to 3> Pigments, aqueous binders, dispersants and water retention agents in terms of concentration in weight ratio shown in Table 1. Mix and adjust with caustic soda to a pH of about 9.2,
A master color 1 was obtained by adjusting the concentration to 64% with water. 100 pigments included in this master color
Parts, mixed so that the concentration conversion amount of the paper coating resin is 0.6 parts, to obtain a paper coating resin composition, the pH and viscosity of each is measured in the following manner, The results are shown in Table 2.

<PH>: The pH of the paper coating agent immediately after preparation was measured at 25 ° C. using a glass electrode type hydrogen ion concentration meter [manufactured by Toa Denpa Kogyo KK].

<Viscosity>: The viscosity of the paper coating agent immediately after preparation was measured at 60 rpm and 25 ° C. using a B type viscometer [BL type manufactured by Tokyo Keiki Co., Ltd.].

[0053]

[Table 1]

Ultra White 90 ^{* 1} : Clay manufactured by Engelhard Minerals. Carbital 90 ^{* 2} : Calcium carbonate Alon T-40 ^{* 3} manufactured by Fuji Kaolin Co., Ltd .: Polyacrylic acid pigment dispersant manufactured by Toagosei Co., Ltd. Starch ^{* 4} : Urea-phosphate esterified denim produced by Nippon Shokubai Co., Ltd. Smartex ^{* 5} : WO SBR latex binder made by A & L Japan.

(Production Example of Paper) A resin composition for paper coating was applied to one side of a high-quality paper having a basis weight of 80 g / m ² using a wire rod so that the coating amount was 15 g / m ^2. did. Immediately after the application, it was dried with hot air at 120 ° C for 30 seconds, then conditioned at 20 ° C and 65% relative humidity for 16 hours, and then supercalendered twice at 60 ° C and linear pressure of 60 kg / cm. It was applied and paper was obtained. The paper thus obtained was tested for water resistance and ink acceptability, and the test results are shown in Table 2. The test method of the coated paper is as follows.

<Water resistance: wet pick method (WP method)>
Using an RI tester (manufactured by Akira Seisakusho), the coated surface was wetted with a water supply roll and then printed, and the peeled state was visually observed and judged. The criteria for judgment were as follows. Water resistance (poor) 1-5 (excellent)

<Ink acceptability> (1) Using the Method A 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 criteria for judgment were as follows. Ink acceptability (poor) 1-5 (excellent)

(2) Using the B method RI tester, a slight gap is made between the metal roll and the rubber roll, water is poured into the gap and printing is performed immediately, and the acceptability of the ink is visually observed. And judged. The criteria for judgment were as follows. Ink acceptability (poor) 1-5 (excellent)

[0059]

[Table 2]

[0060]

The resin for paper coating of the present invention does not substantially contain a crosslinkable compound such as formalin,
When a paper coating resin composition containing the resin as an active ingredient is applied to paper, a coated paper having excellent water resistance and ink acceptability can be obtained. Furthermore, since formalin is not used, formalin is not detected in the coated paper obtained.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuhiro Fukui             Osaka Prefecture Osaka City Konohana-ku 3 Kasuga Naka 3-chome 98             No. Sumika Chemtex Co., Ltd. F term (reference) 4J001 DA01 DC14 EB33 EB35 EB36                       EB37 EB46 EB55 EB67 EB69                       EC03 EC14 EC23 EE24B                       EE28A EE56A EE72A FB03                       FC06 JA17                 4L055 AG80 AH37 AH49 AH50 BE08                       FA15 FA19 GA15

Claims (10)

[Claims] 1. A paper coating resin obtained by reacting polyamines, ureas, and aromatic polycarboxylic acids as essential components and a crosslinkable compound as an optional component. The content of ureas is 0.0 with respect to the total 1 mol of nitrogen atoms contained in the group and the secondary amino group.
5 to 1 mol, the content of aromatic polycarboxylic acids is 0.0
1 to 0.5 mol, and the content of the crosslinkable compound is 0.0
A resin for paper coating, which is 1 mol or less. 2. An α, β-unsaturated carbonyl compound, α, β
-Essentially at least one component selected from the group consisting of unsaturated nitrile compounds, α-halocarboxylic acids, halogenated hydrocarbons and alkylsulfates, polyamines, ureas, and aromatic polycarboxylic acids In a paper coating resin obtained by reacting a crosslinkable compound as a component with an optional component, urea is added to 1 mol of the total nitrogen atoms contained in the primary amino group and secondary amino group of the polyamines. Of 0.05 to 1 mol, the content of aromatic polycarboxylic acids is 0.01 to 0.5 mol, and the content of the crosslinkable compound is 0.01 mol or less. Resin for paper coating. 3. The polyamines is at least one polyamine selected from the group consisting of alkylenediamines, polyalkylenepolyamines, alicyclic polyamines and heterocyclic polyamines. Resin for paper coating. 4. The paper coating resin according to claim 1, wherein the aromatic polycarboxylic acids are benzenedicarboxylic acids. 5. The crosslinkable compound is formaldehyde, polyaldehyde, epihalohydrin, α, ω-dihalo-β-
The resin for paper coating according to any one of claims 1 to 4, which is at least one crosslinkable compound selected from the group consisting of hydrin, polyepoxy compounds and polyisocyanate compounds. 6. A pigment, an aqueous binder and claims 1-5.
A resin composition for paper coating, comprising the resin for paper coating according to any one of 1. 7. The resin composition for paper coating according to claim 6, which contains a non-volatile substance. 8. The resin composition for paper coating according to claim 6, wherein the non-volatile substance is at least one non-volatile substance selected from inorganic salts, ureas and saccharides. 9. A coated paper obtained by coating a paper with the resin composition for paper coating according to claim 5. 10. A method for producing coated paper, which comprises coating the paper with the resin composition for paper coating according to any one of claims 5 to 7.