JP2000219863A - Binder composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a binder composition rapidly thickening on heating into a firm gel despite being low in viscosity at low temperatures by including a specific anionic resin latex, a specific heat-sensitive gelatinizer and a water-soluble polymer. SOLUTION: This binder composition is obtained by including (A) an anionic resin latex <=0.01 mmol/g (resin) in the emulsifier content of the aqueous phase prepared, for example, by emulsion polymerization of a radical-polymerizable monomer in the presence of a radical-polymerizable group-bearing anionic emulsifier by a well-known means (e.g. styrene-butadiene-based resin latex), (B) a cationic group-free heat-sensitive gelatinizer [e.g. an anionic heat-sensitive gelatinizer such as a copolymer of tetraethylene glycol monoethyl ether mono(meth)acrylate and phthalic acid, nonionic heat-sensitive gelatinizer such as a pentaethylene glycol monobutyl ether mono(meth)acrylate polymer], and (C) a water-soluble polymer (e.g. polyvinyl alcohol).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a binder composition, and more particularly, to a thermosensitive gelling binder composition which gives a low-viscosity paint when used in a coating color for producing coated paper.

[0002]

2. Description of the Related Art Conventionally, a heat-sensitive gelling agent such as an alkylene oxide adduct of an alkylphenol formalin condensate is mixed with an anionic resin latex obtained by emulsion polymerization using an ethylenically unsaturated surfactant having an anionic group. A heat-sensitive gelling latex composition has been proposed (JP-A-6-299000). Further, a binder composition comprising an anionic resin latex and a thermosensitive gelling agent containing a cationic group such as a morpholinoethyl methacrylate polymer has also been proposed (Japanese Patent Application Laid-Open No. H9-1990).
-111133 gazette).

[0003]

However, Japanese Patent Application Laid-Open No.
Although the heat-sensitive gelling latex composition disclosed in Japanese Patent Application No. 299000 is gelled by heating, once heated, the emulsion agglomerates and gels, so that it does not redisperse even when cooled, producing coated paper. However, there is a problem that it cannot be used for applications that may be temporarily heated in a coating process such as a coating color. Further, Japanese Patent Application Laid-Open No.
Since the binder composition disclosed in Japanese Patent No. 11133 is thermoreversible in gelation, it can be used for applications that may be temporarily heated in a coating process, and can be used in combination with a water-soluble polymer. It is described that the viscosity of the composition becomes too high due to the formation of the ion complex, especially when the amount of the water-soluble polymer used in combination is large, although it can impart high white paper gloss and printability. There were difficulties.

[0004]

SUMMARY OF THE INVENTION In view of the above problems, the present inventors have also used the present invention for applications that may be temporarily heated in a coating process such as a coating color for manufacturing coated paper. As a result of intensive studies on a binder composition having a temperature-sensitive gelling property that can provide a low-viscosity coating material, the use of a water-soluble polymer in combination with a latex that does not form an ion complex and a temperature-sensitive gelling agent The inventors have found that the above problem can be solved, and have reached the present invention.

That is, according to the present invention, the amount of the emulsifier in the aqueous phase is 0.1.
A binder composition comprising an anionic resin latex (A) of not more than 01 mmol / g (resin), a thermosensitive gelling agent (B) containing no cationic group, and a water-soluble polymer (C). And a coating color for coated paper comprising the binder composition and a pigment.

The resins constituting the anionic resin latex (A) in the present invention include acrylic resins, styrene-acrylic resins, styrene-butadiene resins,
Vinyl polymers such as butadiene-acrylic resin, butadiene-acrylonitrile resin, vinyl acetate resin, ethylene-vinyl acetate resin, ethylene-propylene resin, and polybutadiene resin are exemplified.

The vinyl polymer is a (co) polymer of a radical polymerizable monomer containing no cationic group, and examples of the radical polymerizable monomer include (cyclo)
Alkyl (C 1-22) (meth) acrylate [methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) acrylate , Lauryl (meth) acrylate, octadecyl (meth) acrylate, etc.]; aromatic ring-containing (meth) acrylate [benzyl (meth) acrylate, etc.]; hydroxyl-containing (meth) acrylate [2-hydroxyethyl (meth) acrylate,
2-hydroxypropyl (meth) acrylate, diethylene glycol mono (meth) acrylate, glycerin mono (meth) acrylate, polyglycerin (degree of polymerization 2
To 4) mono (meth) acrylate, etc.]; (meth) acrylamide or a derivative thereof ((meth) acrylamide, N, N-dibutyl (meth) acrylamide, cyclohexyl (meth) acrylamide, N-methyl (meth)
Acrylamide, N-methylol (meth) acrylamide, diacetone acrylamide, etc.]; cyano group-containing monomer [(meth) acrylonitrile, 2-cyanoethyl (meth) acrylate, 2-cyanoethyl acrylamide, etc.]; polyfunctional (meth) acrylate [ Ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 2,2-bis (4-hydroxyethylphenyl) propane di (meth) acrylate, etc.]; styrenes (styrene, α- Methyl styrene, vinyl toluene, divinyl benzene, etc.); diene monomers (butadiene, isoprene, chloroprene, etc.); vinyl esters (vinyl acetate, vinyl propionate, etc.); (Meth) acrylate, allyl glycidyl ether, etc.]; monoolefins (ethylene, propylene, 1-butene, etc.); halogen-containing monomers (vinyl chloride, vinylidene chloride, etc.); heterocyclic-containing monomers (N-vinyl- 2-pyrrolidone, N-methylolmaleimide, N-vinylsuccinimide and the like); unsaturated dibasic acid dialkyl esters [dialkyl maleate (C1 to C8) ester, dialkyl itaconate (C1 to C1)
8) Ester, etc.]; Silyl group-containing monomer [3-trimethoxysilylpropyl (meth) acrylate, etc.]; Anionic group-containing monomer [(meth) acrylic acid, (anhydride) maleic acid, fumaric acid, itacone Acid, vinyl sulfonic acid,
Acids such as (meth) acrylsulfonic acid, styrenesulfonic acid, vinylbenzoic acid, alkyl (C1-10) allylsulfosuccinic acid, (meth) acryloylpolyoxyalkylene (polymerization degree 2-15) sulfate, and salts thereof And combinations of two or more of these.

Of these, preferred are alkyl (meth) acrylates, styrenes and diene monomers, and a combination of a diene monomer with an alkyl (meth) acrylate and / or styrene is particularly preferred.

The amount of the emulsifier in the aqueous phase of the anionic resin latex (A) in the present invention must be 0.01 mmol (mmol) / g (resin) or less.
More preferably, it is not more than 02 mmol / g. When the amount of the emulsifier in the aqueous phase exceeds 0.01 mmol / g, the thermosensitive gelling property is inhibited.

The amount of the emulsifier in the aqueous phase can be determined by analyzing and quantifying the aqueous phase obtained by removing the resin component from the resin latex by liquid chromatography or the like. As a method of removing the resin component from the resin latex, for example, a method of removing the resin component by coagulating and solidifying the resin component after freezing the resin latex, a method of removing the resin component by sedimentation and solidification by a centrifugal separator, an acid or an alkali. In addition, a method of removing and solidifying and removing the resin component may be used.

The amount of the emulsifier in the aqueous phase is 0.01 mmol / g
(Resin) As a method for producing the following anionic resin latex (A), for example, a method in which a radical polymerizable monomer is emulsion-polymerized by a known method using an emulsifier having low solubility in water; a radical polymerizable group A method of emulsion-polymerizing a radical-polymerizable monomer by a known method using an anionic emulsifier (a) having a compound; a method of emulsion-polymerizing a radical-polymerizable monomer by a known method using an anionic protective colloid; A method of synthesizing a polymer having an anionic hydrophilic group (a carboxyl group, a sulfoxyl group, or the like) in a solvent by a known method, neutralizing with a base as necessary, adding water, emulsifying the solvent, and then removing the solvent after emulsification is used. Among these methods, the methods (1) and (2) are preferable in that the resin latex (A) can be easily obtained under ordinary conditions, and the method (2) is particularly preferable.

The cationic emulsifier (a) having a radical polymerizable group includes, for example, (1) anionic (meth) acrylates, those represented by the following formula: CH ₂ ＣC (R ¹ ) CO _{2 (CH 2) mOSO 3 M} CH 2 = C (R 1) CO 2 CH 2 C (R 2) (OCOR 2) C
_{H 2 SO 3 M CH 2 =} C (R 1) CO 2 CH 2 CH 2 OCOArCO 2 CH
₂ CH ₂ OSO ₃ M CH ₂ ＣC (R ¹ ) CO (AO) pOSO ₃ M (wherein R ¹ is a hydrogen atom or a methyl group, m is an integer of 1 to 4, M is an alkali metal ion, ammonium ion or An aminium ion, R ² is an alkyl group, alkenyl group or aralkyl group having 4 to 21 carbon atoms, Ar is an aromatic ring, AO is an oxyalkylene group having 2 to 4 carbon atoms, p is 2
Shows an integer of ~ 200. (2) anionic (meth) acrylamides, such as those represented by the following formula: CH ₂ ＣC (R ¹ ) CONH (CH ₂ ) mOSO ₃ M CH ₂ ＣC (R ¹ ) CON [( _{CH 2) mOSO 3 M] 2} CH 2 = C (R 1) CONH (CH 2) m (AO) pOSO 3
M CH ₂ ＣC (R ¹ ) CON [(CH ₂ ) m (AO) pOSO ₃
M] ₂ (wherein R ¹ is a hydrogen atom or a methyl group, m is an integer of 1 to 4, M is an alkali metal ion, ammonium ion or aminium ion, AO is an oxyalkylene group having 2 to 4 carbon atoms, p is (3) anionic styrene derivatives, such as those represented by the following formulas: CH ₂ ＣC (R ¹ ) ArSO ₃ M CH ₂ ＣC (R ¹ ) Ar (AO) pOSO ₃ M (wherein R ¹ is a hydrogen atom or a methyl group, Ar is an aromatic ring, M is an alkali metal ion, ammonium ion or aminium ion, AO is an oxyalkylene group having 2 to 4 carbon atoms, and p is 2 to (4) anionic allyl compounds, such as those represented by the following formula: CH ₂ ＣＨCHCH ₂ OCOCH (OSO ₃ M) CH ₂ CO ₂
R ² CH ₂ ＣＨCHCH ₂ OCH ₂ CH (OH) CH ₂ OCOCH
(SO ₃ M) CH ₂ CO ₂ R ² (R ² ) (R ³ ) Ar (CH ₂ CH ＝ CH ₂ ) (AO) pO
SO ₃ M (where M is an alkali metal ion, ammonium ion or aminium ion, R ² is an alkyl group, alkenyl group or aralkyl group having 4 to 21 carbon atoms, R ³ is a hydrogen atom or alkyl having 1 to 21 carbon atoms) Group, alkenyl group or aralkyl group, Ar is an aromatic ring, AO has 2 to 2 carbon atoms.
(5) anionic maleic esters, such as those represented by the following formula: R ² OCOCHＣＯCHCO ₂ CH (OH) CH ₂ SO ₃ M ^{R 3 (AO) pOCOCH = CHCO} 2 (CH 2) nCH
(R ³ ) SO ₃ M R ³ (AO) pOCOCH ＝ CHCO ₂ M (wherein R ² is an alkylene group, alkenyl group or aralkyl group having 4 to 21 carbon atoms, M is an alkali metal ion, ammonium ion or aminium ion , R ³ is a hydrogen atom or an alkyl group having 1 to 21 carbon atoms, an alkenyl group or an aralkyl group, AO an oxyalkylene group having 2 to 4 carbon atoms, p is an integer of 2 to 200, n is an integer of 0 to 3 (6) anionic itaconic esters, such as those represented by the following formula: CH ₂ ＣC (CH ₂ CO ₂ R ² ) CO ₂ (CH ₂ ) mOSO ₃ M CH ₂ ＣC (CH ₂ CO ₂ R ² ) CO ₂ CH ₂ CH (OH) C
H ₂ OSO ₃ M (wherein R ² represents an alkylene group, alkenyl group or aralkyl group having 4 to 21 carbon atoms, m represents an integer of 1 to 4, and M represents an alkali metal ion, an ammonium ion or an aminium ion.) And the like.

Among these, (1) anionic (meth) acrylates and (2) anionic (meth) acrylic esters are preferred because they have high copolymerizability with radically polymerizable monomers and good polymerization stability. Meth) acrylic acid amides and (3) anionic styrene derivatives are preferred,
(1) and (3) are particularly preferred.

Emulsifier having the radical polymerizable group (a)
Is usually used in an amount of 0.1 to 20% by weight based on the resin component,
Preferably it is 1 to 10% by weight.

When the anionic resin latex (A) is produced by emulsion polymerization, a known polymerization initiator is used. Examples of the polymerization initiator include organic polymerization initiators (peroxides (cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramenthane hydroperoxide, benzoyl peroxide, lauroyl peroxide, etc.), azo compounds (azobisisobutyrate). Onitrile, azobisisovaleronitrile, etc.), inorganic polymerization initiators [persulfates (sodium persulfate, ammonium persulfate, potassium persulfate, etc.), hydrogen peroxide, etc.]. The amount of the polymerization initiator to be used is generally 0.01 to 5% by weight, preferably 0.1 to 3% by weight, based on the total amount of the monomer mixture.
% By weight.

Known chain transfer agents can be used for adjusting the molecular weight of the resin, the gel content of the latex, and the like. Examples of the chain transfer agent include α-methylstyrene dimer (2,4-diphenyl-4-methyl-1-pentene and the like), terpinolene, terpinene, dipentene,
Alkyl mercaptan having 8 to 18 carbon atoms, 8 to 1 carbon atoms
8 alkylenedithiol, alkyl thioglycolate, dialkylxanthogen disulfide, tetraalkylthiuram disulfide, chloroform, carbon tetrachloride and the like. These can be used alone or in combination of two or more. The amount of the chain transfer agent to be used is generally 0 to 15% by weight, preferably 0 to 5% by weight, based on the total amount of the monomer mixture.

If necessary, a reducing agent [sodium pyrobisulfite, sodium sulfite, sodium hydrogen sulfate,
Ferrous sulfate, glucose, sodium formaldehyde sulfoxylate, L-ascorbic acid (salt)], chelating agent (glycine, alanine, sodium ethylenediaminetetraacetate, etc.), pH buffering agent (sodium tripolyphosphate, potassium tetrapolyphosphate, etc.) And the like may be used in combination. The amount of these additives to be used is generally 0 to 5% by weight, preferably 0 to 3% by weight, based on the total amount of the monomer mixture.

As the anionic resin latex (A), acrylic resin latex, styrene-acrylic resin latex, styrene-butadiene resin latex, and butadiene-based resin latex are preferable in terms of good adhesive strength.
Acrylic resin latex is preferable, and styrene-butadiene resin (styrene unit content: 20 to 60% by weight) latex is more preferable.

The resin latex (A) has a resin concentration of:
Usually, it is 20 to 75%, preferably 40 to 60%. The particle size of the resin latex (A) is usually 5
00 nm or less, preferably 50 to 300 nm, and p
H is usually 3 to 12, preferably 6 to 10. When the particle size exceeds 500 nm or when the pH is less than 3 or more than 12, thermogelling properties may not be sufficiently exhibited.

In addition, G of the resin of the resin latex (A)
The weight average molecular weight by the PC method is usually 10,000 or more,
It is preferably 100,000 to 1,000,000 or more, and the gel content in the resin is usually 5 to 95.
%, Preferably 30 to 80% by weight. The gel content is determined as the content of the toluene-insoluble component in the dried resin.

The thermosensitive gelling agent (B) containing no cationic group in the present invention is a compound having a transition temperature at which a reversible thickening effect of an aqueous liquid is exhibited by heating, and an anionic thermosensitive gel. Agent (B1) and a nonionic thermosensitive gelling agent (B2).

Examples of the anionic thermosensitive gelling agent (B1) include (a) a vinylalkyl (C1-6) ether (eg, vinyl methyl ether) and a monomer having an anionic group [(meth) Acrylic acid, (anhydride) maleic acid, fumaric acid, itaconic acid, vinyl sulfonic acid, (meth) acryl sulfonic acid, styrene sulfonic acid, vinyl benzoic acid, alkyl (1 to 10 carbon atoms) allyl sulfosuccinic acid, (meth) acryloyl Polyoxyalkylene (degree of polymerization 2 to 15), such as a sulfuric acid ester and salts thereof (alkali metal salts, amine salts, etc.)] and (B) N-monosubstituted (meta ) Acrylamide [N-isopropyl (meth) acrylamide, N-methoxypropyl (meth) acrylamide, etc.] and the monomer having an anionic group Copolymers and 須単 monomers;
(C) N, N-disubstituted (meth) acrylamide [N, N
-Diethyl (meth) acrylamide, N- (meth) acryloylpyrrolidine, etc.) and the monomer having an anionic group as essential monomers; (d) alkylene group having 2 to 4 carbon atoms Of polyoxyalkylene (degree of polymerization 3
~ 40) Mono (meth) acrylate of monool or diol [tetraethylene glycol monoethyl ether mono (meth) acrylate, pentaethylene glycol monobutyl ether mono (meth) acrylate, methoxytrioxypropylene tetraoxyethylene (meth) acrylate, tetra Mono (meth) acrylate of ethylene oxide 6 mol adduct of propylene glycol) and a monomer having an anionic group as essential monomer; (e) alkylene group having 2 to 4 carbon atoms
Polyoxyalkylene (degree of polymerization: 3 to 40) monool or diol monovinyl phenyl ether (tetraethylene glycol monomethyl ether monovinyl phenyl ether, pentaethylene glycol monoethyl ether monovinyl phenyl ether, methoxypentaoxypropylene tetraoxyethylene vinyl phenyl ether; Monovinyl phenyl ether of ethylene oxide 8 mole adduct of tetrapropylene glycol) and a monomer having the above-mentioned anionic group-containing monomer as an essential monomer, and an ethylene oxide-modified polysiloxane having an anionic group, Examples thereof include an alkylene oxide adduct of an alkylphenol formalin condensate having an anionic group, and water-soluble celluloses having an anionic group.

Among these, preferred are (d) and (e) in that a lower viscosity composition can be obtained when used in combination with the water-soluble polymer (C) described below.

The molecular weight per anionic group (B1) is usually 100 or more, preferably 150 to 50,000.
0. If the molecular weight per anionic group is less than 100, the thermosensitive gelling property may not be sufficiently exhibited.

Examples of the nonionic thermosensitive gelling agent (B2) include (f) alkylene oxide adducts of alkyl naphthalene formalin condensates (such as those described in JP-A-63-193901); Oxide-modified polyorganosiloxanes (such as those described in JP-A-6-256617); (h) cellulose-based thermosensitive gelling agents (methylcellulose, hydroxymethylcellulose, etc.); (ii) vinylalkyl (C1-6) Ether polymer (vinyl methyl ether polymer, etc.);
(Co) polymers containing mono-substituted (meth) acrylamide as an essential monomer [N-isopropyl (meth) acrylamide polymer, N-methoxypropyl (meth) acrylamide polymer, etc., described in JP-A-1-14276 And the like]; (R) (co) polymer having N, N-disubstituted (meth) acrylamide as an essential monomer [N, N-diethyl (meth) acrylamide polymer, N- (meth) acryloylpyrrolidine Polymers and the like described in JP-A-60-233184]; (e) an alkylene group having 2 to 2 carbon atoms
(Co) polymer having a polyoxyalkylene (polymerization degree of 3 to 40) monool or diol mono (meth) acrylate as an essential monomer [tetraethylene glycol monoethyl ether mono (meth) acrylate polymer,
Pentaethylene glycol monobutyl ether mono (meth) acrylate polymer, methoxytrioxypropylene tetraoxyethylene (meth) acrylate polymer,
Mono (meth) acrylate polymer of ethylene oxide 6 mol adduct of tetrapropylene glycol etc.];
A (co) polymer (tetraethylene glycol monomethyl ether monovinyl phenyl ether polymer) containing, as an essential monomer, a polyoxyalkylene having an alkylene group of 2 to 4 carbon atoms (degree of polymerization: 3 to 40) monool or diol monovinyl phenyl ether as an essential monomer Polymer, pentaethylene glycol monoethyl ether monovinyl phenyl ether polymer, methoxypentaoxypropylene tetraoxyethylene vinyl phenyl ether polymer, monovinyl phenyl ether polymer of tetrapropylene glycol 8 mol ethylene oxide adduct, etc.) and (f) vinyl acetate / Vinyl alcohol copolymer and the like.

Of these, preferred are (e) and (e) in that a lower viscosity composition can be obtained when used in combination with the water-soluble polymer (C) described below.

The cationic thermosensitive gelling agent (B1) can be used in an optional ratio together with the nonionic thermosensitive gelling agent (B2).

The weight-average molecular weight of the thermosensitive gelling agent (B) is
Usually 1,000 to 5,000,000, preferably 2,
000 to 500,000. The transition temperature of (B) is usually 15 to 100 ° C, preferably 40 to 80 ° C.
It is. The transition temperature is determined by gradually heating a 1% aqueous solution of (B) and measuring the temperature at which the aqueous solution starts to become cloudy or gel.

As the water-soluble polymer (C) in the present invention, those usually used for paper processing or fiber treatment, specifically, polyvinyl alcohol or a modified product thereof (polyvinyl alcohol, ethylene-vinyl acetate copolymer) Partially saponified product of union, partially acetalized product of polyvinyl alcohol, etc.); Starch or a modified product thereof (oxidized starch, phosphate esterified starch, cationized starch, casein, soybean protein, synthetic protein, mannangalactan derivative, carboxymethyl cellulose, etc.) Polyacrylamides (acrylamide polymer, acrylamide-sodium (meth) acrylate copolymer, Mannich-modified polyacrylamide, etc.); formalin resin (urea-formalin resin, melamine-formalin resin, etc.), polyethyleneimine, Li amide polyamine - epichlorohydrin, styrene - sodium salt of maleic acid copolymer,
(Meth) acrylic acid alkyl ester- (meth) acrylic acid copolymer soda salt and the like.

Of these, polyvinyl alcohol or a modified product thereof and starch or a modified product thereof are preferred from the viewpoint of providing good water retention.

The number average molecular weight of (C) is usually 2,000
~ 500,000, preferably 10,000-200,
000.

The weight ratio of the solid content of the anionic resin latex (A) and the temperature-sensitive gelling agent (B) in the present invention is usually (50-99.999) :( 0.001-50), preferably (70). ９９99.99): (0.01 to 30). By setting the ratio of (B) within the above range, a coating paper having a low viscosity of the coating at normal temperature, good coating suitability, and gelling at the time of drying by heating to have a high white gloss and high printing suitability is obtained. A binder composition is obtained. Also,
The solid content weight ratio of [(A) + (B)] :( C) is usually (10-95) :( 90-5), preferably (35-9).
0): (65 to 10). By setting the ratio of (C) within the above range, it is possible to obtain a binder composition having low coating viscosity at room temperature and good water retention and good coating suitability.

The composition of the present invention comprising the resin latex (A), the temperature-sensitive gelling agent (B), and the water-soluble polymer (C) comprises (A) and (B) alone or (B) And (C) alone or (C) diluted with water at a temperature lower than the transition temperature of (B) by mixing with a usual mixing device (paddle-type stirring blade or the like). can get.

The composition of the present invention may contain, if necessary, a known pigment [various clay, kaolin, calcium carbonate, satin white, titanium oxide, aluminum hydroxide, barium sulfate, zinc oxide, calcium sulfate, talc, plastic Pigment (beads such as polystyrene, styrene / butadiene copolymer or styrene / acrylic copolymer), etc.]. The pigment content is
It is usually 0 to 25 parts by weight, preferably 3 to 10 parts by weight, based on 1 part by weight of the total solid content of (A) + (B) + (C).

Further, if necessary, a pigment dispersant [sodium poly (meth) acrylate, sodium pyrophosphate, sodium hexametaphosphate, etc.] and an antifoaming agent (mineral oil-based antifoaming agent, silicon-based antifoaming agent, etc.) And other additives [lubricant, pH adjuster, preservative, waterproofing agent, printability improving agent, etc.]. The content of the additive is usually 0 to 2.5 parts by weight, preferably 0.001 part by weight based on 1 part by weight of the total solid content of (A) + (B) + (C).
5 to 0.5 parts by weight.

The binder composition of the present invention has the characteristics of having a low viscosity at room temperature, a thermosensitive gelling property upon heating and drying to increase the viscosity, and returning to the original low viscosity when cooled. It is particularly useful as a binder for paper coating colors. Further, it can be suitably used as a carpet backing binder, a binder for nonwoven fabric, a binder for various paints, a binder for printing ink, an adhesive, a ceramic binder, and a binder for glass fiber.

An example of the formulation of a coating color for coated paper using the binder composition of the present invention is as follows (parts by solids). (Normal) (preferably) resin latex (A) 2 to 50 to 25 thermosensitive gelling agent (B) 0.0001 to 50 0.0005 to 11 water-soluble polymer (C) 2 to 50 5 to 25 pigment 100 100 Pigment dispersant 0-10 0.05-5 Other additives 0-10 0.05-5 Further, the solid content concentration of the coating color for coated paper is usually 10-10.
It is 80% by weight, preferably 30 to 65% by weight.

Next, a method for producing a coating color for coated paper using the binder composition of the present invention will be exemplified.
First, a pigment is dispersed in water using a dispersing device in the presence of a pigment dispersant, an antifoaming agent, etc., to obtain a pigment slurry. Next, a coating color is obtained by blending the binder composition of the present invention and the other additives described above. High-speed mixers, kedi mills,
A speed mill, a sigma blade kneader, a more house mill, a lead kneader and the like can be mentioned.

The coated paper is obtained by applying a coating color for coated paper to a base paper for coating using a coating machine, heating and drying and, if necessary, smoothing. The coating amount of the coating color is usually 1 to 50 g / m ² as a weight after drying is preferably 5 to 25 g / m ^2.

There is no particular limitation on the base paper for coating, and high quality paper, medium quality paper or lower grade paper of acid or neutral paper (basis weight 3
5 to 400 g / m ² ) is used as it is or after calendering. If necessary, a modified starch aqueous solution, a general coating color or a coating color obtained by using the binder composition of the present invention may be dried in an amount of 0.1 to 50 g / m ^{2 as a} preliminary coating. The coated paper may be used as a base paper for coating, and if necessary, the pre-coated paper which has been subjected to a smoothing treatment in advance may be used as the base paper.

The coating is performed in one or two or more layers by a coating machine. Coating machines include roll coaters (size presses, gate roll coaters, etc.), double-sided simultaneous coating type coaters (build blade coaters, twin blade coaters, etc.), various blade coaters (bench type coaters, helicopters, etc.), air knife coaters , A rod coater, a brush coater, a curtain coater, a chaplex coater, a bar coater, a gravure coater and the like.

The coated paper coated with the coating color is dried by a drier and then subjected to a smoothing treatment as required. Dryers include infrared dryers, drum dryers, air cap dryers, air wheel dryers, air conditioner bear dryers and combinations thereof.
The drying temperature varies depending on the type of dryer, but the temperature inside the dryer is usually 50 to 300 ° C.

The smoothing process is performed using a normal calendar (super calendar, gloss calendar, soft calendar,
(A machine calendar or the like) on-machine or off-machine, and can also be performed by a so-called cast finish such as a wet casting method using a cast drum, a re-wet casting method or a gelling casting method. The processing pressure and temperature are not particularly limited, and the nip pressure is usually 20 to 500 kg / cm, and the temperature is usually room temperature to 300 ° C. The number of pressure nips is usually 1
~ 15. In addition, a water application device using a roll, an electrostatic humidifier, a steam humidifier, or the like may be disposed together with the calendar for humidity control and humidification of the processed paper after finishing.

[0044]

EXAMPLES The present invention will be further described with reference to the following examples, but the present invention is not limited to these examples. Parts in Examples are parts by weight and% is% by weight.

Production Example 1 8.5 parts of tetraethylene glycol monoethyl ether monoacrylate, 1.5 parts of methacrylic acid and 2,2
2'-azobis (2,4-dimethylvaleronitrile)
Add 0.01 part to the ampoule, freeze, deaerate and seal.
At 8 ° C. for 8 hours to form an anionic thermosensitive gelling agent (B
1-1) was obtained. The number average molecular weight (GP) of (B1-1)
C, the same hereinafter) was about 250,000, and the transition temperature (1% aqueous solution, hereinafter the same) was 55 ° C.

Production Example 2 9 parts of polyethylene glycol (degree of polymerization = 7) monobutyl ether monomethacrylate and 0.01 part of 2,2′-azobis (2,4-dimethylvaleronitrile) were added to an ampoule, which was then deaerated by freezing and sealed. The mixture was polymerized at 50 ° C. for 8 hours to obtain a nonionic thermosensitive gelling agent (B2-1).
The (B2-1) had a number average molecular weight of about 200,000 and a transition temperature of 60 ° C.

Production Example 3 102 parts of water, 45 parts of styrene, 9 parts of methyl methacrylate, 4 parts of methacrylic acid, and a radical polymerizable group were placed in a pressurized reaction vessel equipped with a stirrer, a dropping cylinder, a nitrogen gas inlet tube, and a thermometer. 5 parts of sodium salt of acryloyloxypolypropylene (degree of polymerization = 12), 1 part of sodium persulfate and 0.2 part of lauryl mercaptan were charged as an emulsifier having the same, and the system was replaced with nitrogen gas under stirring and then butadiene was added from a dropping cylinder. 37 parts were injected and reacted at 50 ° C. for 30 hours and further at 85 ° C. for 5 hours. Then, the unreacted monomer was stripped under reduced pressure, and the pH was adjusted to 9.0 with an aqueous sodium hydroxide solution to give a solid content of 48.1.
% Anionic SBR resin latex (hereinafter referred to as SBR)
). The amount of the emulsifier in the aqueous phase of this latex was 0.0003 mmol / g (resin).

Production Example 4 In the same manner as in Production Example 3, styrene 50 parts, methyl methacrylate 6 parts, itaconic acid 2 parts, acrylonitrile 5
Parts, butadiene 32 parts and acryloyloxypolypropylene (degree of polymerization = 12) sulfate 5% Na salt, an anionic SBR resin latex (hereinafter referred to as SBR) having a solid content of 48.1% was obtained. The amount of the emulsifier in the aqueous phase of this latex was 0.0004 mmol / g (resin).

Production Example 5 102 parts of water, 45 parts of styrene, 9 parts of methyl methacrylate, 4 parts of dimethylaminoethyl methacrylate, radical polymerizable in a pressurized reaction vessel equipped with a stirrer, a dropping cylinder, a nitrogen gas inlet tube and a thermometer. N, N as an emulsifier having a group
Propylene oxide of dimethylethanolamine 12
5 parts of ethyl chloride quaternary ammonium salt of a (meth) acrylic acid ester of a molar adduct, 1 part of t-butyl hydroperoxide and 0.2 part of lauryl mercaptan were charged, and the system was replaced with nitrogen gas under stirring and then replaced with nitrogen gas. 37 parts of butadiene was press-fitted from a dropping cylinder and reacted at 70 ° C. for 30 hours and further at 85 ° C. for 10 hours. Then, unreacted monomers are stripped under reduced pressure, and the pH is adjusted to pH 6.
By adjusting to 5, a cationic SBR resin latex having a solid content of 47.9% (hereinafter referred to as SBR)
I got The emulsifier amount of the aqueous phase of this latex was 0.000.
It was 3 mmol / g (resin).

Examples 1 to 4 and Comparative Examples 1 and 2 Each component was blended according to the formulation shown in Table 1 to prepare binder compositions 1 to 4 of the present invention and binder compositions 5 to 6 for comparison.
Was prepared.

[0051]

[Table 1]

(Note 1) PVA: polyvinyl alcohol [Kuraray Co., Ltd., PV
A-117] 20% aqueous solution MS: 30% aqueous solution of pregelatinized phosphate esterified starch [MS # 4600, manufactured by Nippon Shokuhin Kako Co., Ltd.]

Examples 5 to 8, Comparative Examples 3 and 4 25 parts of water Dispersant [SN Dispersant 5040 manufactured by San Nopco Co., Ltd.] 0.3 part Sodium hydroxide 0.1 part Antifoaming agent [San Nopco Co., Ltd.] Nopco DF122-NS] 0.1 part Clay 45 parts Calcium carbonate 5 parts The above components were dispersed and mixed with a disper (2,000 rpm) for 30 minutes.
0 parts were added and mixed uniformly, and coating colors 1 to 6 were adjusted. The viscosity at 25 ° C. of each coating color was measured (using a B-type viscometer and ST rotor; the same applies hereinafter). 80 ° C
In a hot water bath for 30 minutes and the viscosity at 80 ° C. was measured.
After measuring the viscosity at 80 ° C., it was placed in a water bath at 25 ° C. for 30 minutes to measure the viscosity after cooling. Table 2 shows the results.

[0054]

[Table 2]

Each of the coating colors 1 to 6 was coated on a medium paper of 58 g / m ² using a sheet-blade coater so as to have a dry coating amount of about 8 g / m ² and dried (coating speed). ; 30
m / min, dry air temperature; 150 ° C., drying time; 30
Seconds). Then treated with mini super calendar (temperature 6
Coated papers were prepared at 0 ° C., a nip pressure of 100 kg / cm, and paper passing twice), and the white paper gloss and printed gloss of each coated paper were measured. Table 3 shows the results.

[0056]

[Table 3]

(Note 2) Printing: Offset ink was solid-coated with an RI printing machine manufactured by Meiji Seisakusho Co., Ltd. Gloss; 75 ° gloss of a blank or printed surface was measured with a gloss meter manufactured by Tokyo Denshoku Co., Ltd.

[0058]

The binder composition of the present invention is a thermoreversible thermosensitive gelling binder composition which has a low viscosity at a low temperature but rapidly thickens by heating to form a strong gel. If this is used for the production of coated paper, a coated color having good flowability and excellent coatability can be given as compared with conventional ones, and coated paper having high white gloss and printability can be obtained. Also,
Since it has low viscosity and excellent workability, it is also useful as an application agent for various fabrics, films or sheets, an impregnating agent, etc.
It is also useful as a binder for adhesives and paints.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09D 133/14 C09D 201/00 201/00 C09J 103/00 C09J 103/00 133/14 133/14 C08L 101 / 00 F term (reference) 4J002 AB033 AB043 AB053 AC051 AC071 AC081 AD023 AD033 BB061 BB151 BB223 BC071 BE023 BE033 BF021 BG001 BG013 BG023 BG123 BH013 CC163 CC183 CH052 CM013 FD091 CC02 CC031 CG071 CG121 CG141 CG142 CG161 CG171 CG172 CH031 CH041 CH071 CH081 CH111 CH121 CH142 CH171 CK001 CK031 DA141 DA161 DB221 DJ011 GA06 GA13 MA08 MA10 NA16 PC10 4J040 BA032 BA122 BA152 CA031 DA031 DA041 DA05 DB01 DG01 DC03 DD01 DC03 JA03 JB01 LA11 MA09 MB15 NA10

Claims (8)

[Claims] 1. The amount of an emulsifier in an aqueous phase is 0.01 mmol / g.
(Resin) A binder composition comprising the following anionic resin latex (A), a thermosensitive gelling agent (B) containing no cationic group, and a water-soluble polymer (C). 2. The binder composition according to claim 1, wherein (A) is a resin latex obtained using an anionic emulsifier (a) having a radical polymerizable group. (B) a poly (oxyalkylene monool or diol mono (meth) acrylate and / or polyoxyalkylene monool or diol monovinylphenyl ether) and a vinyl monomer having an anionic group. 3. The binder composition according to claim 1, which is an anionic thermosensitive gelling agent comprising a copolymer (B1) as an essential monomer. 4. The binder composition according to claim 3, wherein the molecular weight per anionic group (B1) is from 150 to 50,000. 5. A (co) polymer comprising (B) a mono (meth) acrylate of a polyoxyalkylene monool or a diol and / or a monovinyl phenyl ether of a polyoxyalkylene monool or a diol as an essential monomer. The binder composition according to claim 1 or 2, which is a nonionic thermosensitive gelling agent comprising B2). 6. The binder composition according to claim 1, wherein (C) is polyvinyl alcohol or a modified product thereof and / or starch or a modified product thereof. 7. The solid content weight ratio of (A) :( B) is (7)
0 to 99.99): (0.01 to 30), and the solid content weight ratio of [(A) + (B)] :( C) is (35 to 9).
90): The binder composition according to any one of claims 1 to 6, which is (65 to 10). 8. A coating color for coated paper comprising the binder composition according to claim 1 and a pigment.