JP5891631B2 - Resin fine particles for binder resin for water-based inkjet, and inkjet ink using the same - Google Patents

Description

The present invention relates to resin fine particles for a binder resin for water-based inkjets, which are excellent in ink storage stability and ejection stability, and exhibit good film resistance (rubbing resistance, water resistance, solvent resistance) at low temperature drying.

A water-based inkjet ink is generally composed of a pigment, water, a hydrophilic solvent (humectant, penetrant), and a binder resin. Among these, the binder resin is used for the purpose of improving the coating film resistance of the printed matter. However, in the case of inkjet, it is necessary to consider the ink discharge property at the same time. Many resin fine particles having a low viscosity are used. Various resin fine particles have been reported in order to further improve the coating film resistance of printed matter while maintaining ink ejection stability and storage stability.
In Patent Document 1, an aqueous inkjet having the same polarity as the colorant, a glass transition temperature (Tg) of resin fine particles of 35 ° C. or higher, and a minimum film-forming temperature (MFT) of 20 ° C. or lower. Ink compositions are disclosed. However, no consideration is given to the stability of the resin fine particles with respect to the hydrophilic solvent contained in the ink solvent, and there is a problem in the ejection stability and storage stability of the ink composition.

In Patent Document 2, a glass transition temperature (Tg) of resin fine particles is 40 to 80 ° C., and a water-soluble surface agent selected from the group consisting of monoalkyl ethers of alkylene glycol, 2-pyrrole, N-methylpyrrolidone, and sulfolane. A water-based ink-jet ink composition is disclosed. Also in this regard, the resin composition with respect to the hydrophilic solvent is not considered, and it is difficult to realize excellent storage stability and ejection stability of the resin fine particles only by the glass transition temperature of the resin. Moreover, since the film forming property of the resin fine particles is poor, the coating film resistance of the printed matter is also a problem.
Patent Document 3 discloses a water-based inkjet ink composition comprising sulfonic acid group-containing resin fine particles, an acetylene glycol penetrant, and triethylene glycol monobutyl ether. However, if the resin fine particles only have a sulfonic acid group, the storage stability of the resin fine particles and the coating film resistance of the printed matter cannot be sufficiently achieved.

Japanese Patent No. 4079339 Japanese Patent No. 3937170 Japanese Patent No. 398235

The present invention provides resin fine particles for a binder resin for water-based ink inks that are excellent in storage stability and ejection properties of ink and that exhibit good film resistance (rubbing resistance, water resistance, solvent resistance) at low temperature drying. Objective.

The first invention is
Aromatic ethylenically unsaturated monomer (A) having no ionic functional group (A) 0 to 20% by weight;
At least one sulfonic acid group-containing ethylenically unsaturated monomer (B) selected from sodium styrene sulfonate, ammonium styrene sulfonate, 2-acrylamide 2-methylpropane sulfonic acid, and sodium allyl sulfonate, or phosphoric acid group-containing Ethylenically unsaturated monomer (C) 0.5-3.0 wt%;
0.1 to 3.0% by weight of a nonionic water-soluble ethylenically unsaturated monomer (D) (except for the case of the following monomer (E));
0.1 to 10% by weight of a crosslinkable ethylenically unsaturated monomer (E);
At least one (meta) selected from a linear or branched alkyl group-containing (meth) acrylate monomer, an alicyclic alkyl group-containing (meth) acrylate monomer, and a fluorinated alkyl group-containing (meth) acrylate monomer ) Acrylate monomers (excluding (A) to (E)) 64 wt% to 99.3 wt%;
The present invention relates to resin fine particles (F) for binder resins for water-based inkjets obtained by emulsion polymerization of ethylenically unsaturated monomers containing.
Moreover, 2nd invention is related with the resin fine particle of 1st invention whose average particle diameter of resin fine particle (F) is 50-200 nm.
Moreover, 3rd invention is related with the resin fine particle of 1st or 2nd invention whose glass transition temperature of resin fine particle (F) is -20-40 degreeC.
The fourth invention relates to the resin fine particles according to any one of the first to third inventions, wherein the crosslinkable ethylenically unsaturated monomer (E) is an alkoxysilyl group-containing ethylenically unsaturated monomer.
Moreover, 5th invention is related with the inkjet ink containing the resin fine particle of any one of 1st-4th invention.

According to the present invention, a resin fine particle for a binder resin for water-based inkjet that exhibits excellent storage stability and ejection stability of ink, and exhibits good coating resistance (rubbing resistance, water resistance, solvent resistance) at low temperature and temperature drying. I was able to provide it.

The binder resin composition for water-based inkjets of the present invention includes resin fine particles (F) for binder resins for water-based inkjets, and the resin fine particles (F)
Aromatic ethylenically unsaturated monomer (A) having no ionic functional group (A) 0 to 20% by weight;
At least one sulfonic acid group-containing ethylenically unsaturated monomer (B) selected from sodium styrene sulfonate, ammonium styrene sulfonate, 2-acrylamide 2-methylpropane sulfonic acid, and sodium allyl sulfonate, or phosphoric acid group-containing Ethylenically unsaturated monomer (C) 0.5-3.0 wt%;
0.1 to 3.0% by weight of a nonionic water-soluble ethylenically unsaturated monomer (D) (except for the case of the following monomer (E));
0.1 to 10% by weight of a crosslinkable ethylenically unsaturated monomer (E);
At least one (meta) selected from a linear or branched alkyl group-containing (meth) acrylate monomer, an alicyclic alkyl group-containing (meth) acrylate monomer, and a fluorinated alkyl group-containing (meth) acrylate monomer ) Acrylate monomers (excluding (A) to (E)) 64 wt% to 99.3 wt%;
It is a resin fine particle (F) formed by emulsion polymerization of an ethylenically unsaturated monomer containing.

Specific examples of the ionic functional group in the present invention include a carboxyl group, a phosphoric acid group, a sulfonic acid group, and salts thereof as an anionic functional group, and an amino group and a salt thereof as a cationic functional group. And a quaternary ammonium base.
Examples of the aromatic ethylenically unsaturated monomer (A) having no ionic functional group include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, m-methylstyrene, vinylnaphthalene, and benzyl. Acrylate, benzyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, phenoxydiethylene glycol acrylate, phenoxydiethylene glycol methacrylate, phenoxytetraethylene glycol acrylate, phenoxytetraethylene glycol methacrylate, phenoxyhexaethylene glycol acrylate, phenoxyhexaethylene glycol methacrylate, phenyl acrylate, phenyl methacrylate Etc.

The content of the aromatic ethylenically unsaturated monomer (A) having no ionic functional group in the total 100% by weight of the ethylenically unsaturated monomer used to obtain the resin fine particles (F) is: It is preferably 0 to 20% by weight. When the content exceeds 20% by weight, the fluidity of the resin fine particles (F) in the ink composition containing a large amount of a hydrophilic solvent such as glycerin or glycol-based solvent is significantly lowered, and the ink composition becomes a nozzle. It will cause clogging.
The water-soluble ethylenically unsaturated monomer used in the present invention includes a sulfonic acid group-containing ethylenically unsaturated monomer (B) or a phosphoric acid group-containing ethylenically unsaturated monomer (C), and a nonionic property. Water-soluble ethylenically unsaturated monomer (D). Excellent ion dissociation of sulfonic acid group-containing ethylenically unsaturated monomer (B) or phosphoric acid group-containing ethylenically unsaturated monomer (C), and nonionic water-soluble ethylenically unsaturated monomer Due to the steric repulsion of the hydrophilic part (D), the resin fine particles (F) can exist stably even in an aqueous medium containing a large amount of a hydrophilic solvent such as glycerin or glycol solvent. Accordingly, the re-solubility of the ink composition containing the resin fine particles (F) is very excellent.

The term “water-soluble” as used herein refers to a case where the amount of ethylenically unsaturated monomer dissolved in 1 L of water at 25 ° C. is 10 g or more.
In the present invention, those having a sulfonic acid group or phosphoric acid group neutralized with a basic substance and having a salt structure may also be used as the sulfonic acid group-containing ethylenically unsaturated monomer (B) and phosphorus. It shall be included in an acid group containing ethylenically unsaturated monomer (C).

Examples of the sulfonic acid group-containing ethylenically unsaturated monomer (B) include styrene sulfonic acid, sodium styrene sulfonate, ammonium styrene sulfonate, 2-acrylamide 2-methylpropane sulfonic acid, and 2-acrylamide 2-methylpropane sulfone. Acid sodium, methallyl sulfonic acid, sodium methallyl sulfonate, allyl sulfonic acid, sodium allyl sulfonate, ammonium allyl sulfonate, vinyl sulfonic acid, allyloxybenzene sulfonic acid, sodium allyloxybenzene sulfonate, allyloxybenzene sulfonic acid Examples include ammonium.
As the phosphoric acid group-containing ethylenically unsaturated monomer (C), 2-methacryloyloxyethyl acid phosphate, 2-acryloyloxyethyl acid phosphate, diphenyl-2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate And dibutyl-2-acryloyloxyethyl phosphate.

  The sulfonic acid group-containing ethylenically unsaturated monomer (B) or the phosphoric acid group-containing ethylenically unsaturated monomer in a total of 100% by weight of the ethylenically unsaturated monomer used to obtain the resin fine particles (F). The content of the monomer (C) is preferably 0.5 to 3% by weight. When the content is less than 0.5% by weight, the dispersion stability of the resin fine particles (F) in the ink composition is lowered. When the content exceeds 3% by weight, agglomerates are generated during emulsion polymerization, which adversely affects the ejection stability of the ink composition, and the water resistance and solvent resistance of the printed matter are lowered.

Examples of the nonionic water-soluble ethylenically unsaturated monomer (D) include (meth) acrylamide, N-methoxymethyl- (meth) acrylamide, N-ethoxymethyl- (meth) acrylamide, and N-propoxymethyl. -(Meth) acrylamide, N-butoxymethyl- (meth) acrylamide, N-pentoxymethyl- (meth) acrylamide, N, N-di (methoxymethyl) acrylamide, N-ethoxymethyl-N-methoxymethyl methacrylamide, N, N-di (ethoxymethyl) acrylamide, N-ethoxymethyl-N-propoxymethyl methacrylamide, N, N-di (propoxymethyl) acrylamide, N-butoxymethyl-N- (propoxymethyl) methacrylamide, N, N-di (butoxymethyl) acrylic De, N- butoxymethyl -N- (methoxymethyl) methacrylamide, N, N- di (pentoxymethyl) acrylamide, N- methoxymethyl -N- (pent carboxymethyl) methacrylamide, N, N- dimethylacrylamide, Amide group-containing ethylenically unsaturated monomers such as N, N-diethylacrylamide and diacetone (meth) acrylamide;
Hydroxyl group-containing ethylenically unsaturated monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, glycerol mono (meth) acrylate, allyl alcohol;
Polyethylene glycol mono (meth) acrylate (Nippon Yushi Co., Ltd., Bremer PE-90, 200, 350, 350G, AE-90, 200, 400, etc.) Polyethylene glycol / polypropylene glycol mono (meth) acrylate (Nippon Yushi Co., Ltd., Blemmer 50PEP-300, 70PEP-350, etc.), polyethylene oxide group-containing ethylenically unsaturated monomers such as methoxypolyethylene glycol mono (meth) acrylate (manufactured by NOF Corporation, BLEMMER PME-400, 550, 1000, 4000, etc.);
However, it is not particularly limited to these. These can be used alone or in combination of two or more.

  The content of the nonionic water-soluble ethylenically unsaturated monomer (D) in the total 100% by weight of the ethylenically unsaturated monomer used to obtain the resin fine particles (F) is 0.1 to It is preferably 3% by weight. When the content is less than 0.1% by weight, the dispersion stability of the resin fine particles (F) in the ink composition is lowered. When the content exceeds 3% by weight, the resin fine particles (F) are thickened, which adversely affects the ink ejection properties. In addition, the water resistance and solvent resistance of the printed matter also deteriorates.

The total amount of the water-soluble ethylenically unsaturated monomer is preferably 0.6 to 6% by weight in a total of 100% by weight of the ethylenically unsaturated monomers used for obtaining the resin fine particles (F). . When the content is less than 0.6% by weight, the dispersion stability of the resin fine particles (F) in the ink composition is lowered. When the content exceeds 6% by weight, the resin fine particles (F) are thickened, which adversely affects the ink ejection properties. In addition, the water resistance and solvent resistance of the printed matter also deteriorates.
The crosslinkable ethylenically unsaturated monomer (E) used in the present invention functions to further improve the stability of the resin fine particles (F) in the ink composition by crosslinking the inside of the resin fine particles.

As the crosslinkable ethylenically unsaturated monomer (E), for example,
Allyl (meth) acrylate, vinyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol (meth) acrylate, 1,4-butanediol di (Meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, Glycerin dimethacrylate, dimethylol tricyclodecane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra ( Data) acrylate, divinylbenzene, divinyl adipate, diallyl isophthalate, diallyl phthalate, ethylenically unsaturated monomer having two or more ethylenically unsaturated groups such as diallyl maleate;
γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropyltributoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-acryloxy Propyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-acryloxypropylmethyldimethoxysilane, γ-methacryloxymethyltrimethoxysilane, γ-acryloxymethyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane Alkoxysilyl group-containing ethylenically unsaturated monomers such as vinyltributoxysilane and vinylmethyldimethoxysilane;
Examples include, but are not limited to, methylol group-containing ethylenically unsaturated monomers such as N-methylol (meth) acrylamide, N, N-dimethylol (meth) acrylamide, and alkyl etherified N-methylol (meth) acrylamide. It is not something. These can be used alone or in combination of two or more.
The content of the crosslinkable ethylenically unsaturated monomer (E) is 0.1 to 10% by weight in a total of 100% by weight of the ethylenically unsaturated monomer used to obtain the resin fine particles (F). Preferably there is. When the content is less than 0.1% by weight, the storage stability and ejection stability of the ink composition are deteriorated. On the other hand, when the content exceeds 10% by weight, the film forming property of the resin fine particles (F) is lowered, and the rub resistance and solvent resistance of the printed matter are lowered.

  Among the crosslinkable ethylenically unsaturated monomers listed above, the crosslinkable ethylenically unsaturated monomer (E) is preferably an alkoxysilyl group-containing ethylenically unsaturated monomer. In general, when a crosslinkable ethylenically unsaturated monomer is used, the stability of the resin fine particles in the ink composition increases, but the film-forming property at the time of drying tends to slightly decrease. However, the alkoxysilyl group-containing ethylenically unsaturated monomer hardly reduces the film-forming property when the resin fine particles are dried, and in an aqueous medium containing a large amount of a hydrophilic solvent such as glycerin or glycol solvent. Dispersion stability is also good.

  Further, the ethylenically unsaturated monomer used for obtaining the resin fine particles (F) includes the above-mentioned ethylenic monomers (A), (B), (C), (D), and (E). In addition, an ethylenically unsaturated monomer copolymerizable with the ethylenic monomers (A), (B), (C), (D), and (E) may be contained.

Examples of ethylenic monomers copolymerizable with the ethylenically unsaturated monomers (A), (B), (C), (D), and (E) include methyl (meth) acrylate and ethyl (meth). Acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, heptyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl Linear or branched alkyl group-containing ethylene such as (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, etc. Unsaturated monomers;
Alicyclic alkyl group-containing ethylenically unsaturated monomers such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate;
Fluorinated alkyl group-containing ethylenically unsaturated monomers such as trifluoroethyl (meth) acrylate and heptadecafluorodecyl (meth) acrylate;
Etc.

These ethylenically unsaturated monomers may be used alone or in combination of two or more.
Since the resin fine particles (F) obtained by emulsion polymerization of various ethylenically unsaturated monomers in the range described above are very excellent in dispersion stability, there are very few aggregates causing nozzle clogging. Further, even in an ink solvent containing a large amount of a hydrophilic solvent such as glycerin or a glycol-based solvent, it does not aggregate during mixing, and is excellent in stability over time. On the other hand, since the film-forming property is very good at the time of drying, the printed matter exhibits excellent coating film resistance.

  The average particle size of the resin fine particles (F) is preferably 50 to 200 nm, and more preferably 70 to 150 nm. The average particle size greatly affects the storage stability and ejection stability of the ink composition. When the average particle size is less than 50 nm, the storage stability of the resin fine particles (F) in the ink composition may be deteriorated. When the average particle diameter exceeds 200 nm, the dischargeability of the ink composition may be deteriorated, or the gloss of the printed matter may be adversely affected due to poor film formation of the resin fine particles (F). Moreover, if many coarse particles having a particle diameter exceeding 1 μm are contained, the discharge property of the ink jet is remarkably deteriorated. Accordingly, it is preferable that the coarse particles exceeding 1 μm are at most 1% by weight.

The average particle diameter is a value measured by a dynamic light scattering method in which a laser dilution is irradiated to a water dilution of a resin fine particle aqueous dispersion and the Brownian motion of the particles is detected from the scattered light.
The glass transition temperature (Tg) of the resin fine particles (F) is preferably -20 to 40 ° C. If the glass transition temperature (Tg) is less than −20 ° C., the water resistance and solvent resistance of the printed matter may not be sufficiently exhibited. When the glass transition temperature (Tg) exceeds 40 ° C., the film forming property of the resin fine particles (F) is deteriorated, and the printed sheet may be deteriorated in abrasion resistance, water resistance, and solvent resistance.
Said glass transition temperature (Tg) is the value calculated | required using DSC (differential scanning calorimeter) The resin fine particle (F) used for this invention is synthesize | combined by a conventionally well-known emulsion polymerization method.
As the emulsifier used in the emulsion polymerization in the present invention, a conventionally known one such as a reactive emulsifier having an ethylenically unsaturated group or a non-reactive emulsifier having no ethylenically unsaturated group may be arbitrarily used. it can.

  Reactive emulsifiers having an ethylenically unsaturated group can be further roughly classified into anionic and nonionic nonionic ones. Especially when anionic reactive emulsifier or nonionic reactive emulsifier having an ethylenically unsaturated group is used, the dispersed particle size of the copolymer becomes fine and the particle size distribution becomes narrow, so it is used as a binder resin for aqueous inkjet inks. In this case, the friction resistance and alcohol resistance can be improved. This anionic reactive emulsifier or nonionic reactive emulsifier having an ethylenically unsaturated group may be used singly or in combination.

Specific examples of the anionic reactive emulsifier having an ethylenically unsaturated group are shown below, but the emulsifiers that can be used in the present invention are not limited to those described below. Examples of the emulsifier include alkyl ethers (commercially available products include, for example, Aqualon KH-05, KH-10, KH-20, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Adeka Soap SR-10N, SR-20N manufactured by ADEKA Corporation. Latemuru PD-104 manufactured by Kao Corporation);
Sulfosuccinic acid ester-based (for example, LATEMUL S-120, S-120A, S-180P, S-180A, Sanyo Chemical Co., Ltd., Elemiol JS-2, etc., manufactured by Kao Corporation);
Alkyl phenyl ether type or alkyl phenyl ester type (commercially available products include, for example, Aqualon H-2855A, H-3855B, H-3855C, H-3856, HS-05, HS-10, HS, manufactured by Daiichi Kogyo Seiyaku Co., Ltd. -20, HS-30, Adeka Soap SDX-222, SDX-223, SDX-232, SDX-233, SDX-259, SE-10N, SE-20N, etc. manufactured by ADEKA Corporation);
(Meth) acrylate sulfate-based (commercially available products include, for example, Antox MS-60, MS-2N, Sanyo Chemical Industries Co., Ltd., Elemiol RS-30, manufactured by Nippon Emulsifier Co., Ltd.);
Examples of the phosphoric acid ester (commercially available products include H-3330PL manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Adeka Soap PP-70 manufactured by ADEKA Co., Ltd., etc.)

Nonionic reactive emulsifiers that can be used in the present invention include, for example, alkyl ether-based (commercially available products such as Adeka Soap ER-10, ER-20, ER-30, ER-40, manufactured by ADEKA Corporation, Latemu PD-420, PD-430, PD-450, etc. manufactured by Kao Corporation);
Alkyl phenyl ether type or alkyl phenyl ester type (commercially available products include, for example, Aqualon RN-10, RN-20, RN-30, RN-50, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., ADEKA rear soap NE- manufactured by ADEKA Co., Ltd. 10, NE-20, NE-30, NE-40, etc.);
(Meth) acrylate sulfate esters (commercially available products include, for example, RMA-564, RMA-568, and RMA-1114 manufactured by Nippon Emulsifier Co., Ltd.).

  When the resin fine particles (F) of the present invention are obtained by emulsion polymerization, a non-reactive emulsifier having no ethylenically unsaturated group may be used in combination with the above-described reactive emulsifier having an ethylenically unsaturated group, if necessary. it can. Non-reactive emulsifiers can be broadly classified into non-reactive anionic emulsifiers and non-reactive nonionic emulsifiers.

Examples of non-reactive nonionic emulsifiers include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether and polyoxyethylene stearyl ether;
Polyoxyethylene alkylphenyl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether;
Sorbitan higher fatty acid esters such as sorbitan monolaurate, sorbitan monostearate, sorbitan trioleate;
Polyoxyethylene sorbitan higher fatty acid esters such as polyoxyethylene sorbitan monolaurate;
Polyoxyethylene higher fatty acid esters such as polyoxyethylene monolaurate and polyoxyethylene monostearate;
Glycerin higher fatty acid esters such as oleic acid monoglyceride and stearic acid monoglyceride;
Examples include polyoxyethylene / polyoxypropylene / block copolymer, polyoxyethylene distyrenated phenyl ether, and the like.

Examples of non-reactive anionic emulsifiers include higher fatty acid salts such as sodium oleate;
Alkylaryl sulfonates such as sodium dodecylbenzenesulfonate;
Alkyl sulfate salts such as sodium lauryl sulfate;
Polyoxyethylene alkyl ether sulfate esters such as sodium polyoxyethylene lauryl ether sulfate;
Polyoxyethylene alkylaryl ether sulfate salts such as sodium polyoxyethylene nonylphenyl ether sulfate;
Alkyl sulfosuccinic acid ester salts such as sodium monooctyl sulfosuccinate, sodium dioctyl sulfosuccinate, sodium polyoxyethylene lauryl sulfosuccinate and derivatives thereof;
Examples thereof include polyoxyethylene distyrenated phenyl ether sulfate salts.
The amount of the emulsifier used at the time of emulsion polymerization is preferably 0.5 to 2.0 parts by weight with respect to 100 parts by weight of the total of ethylenically unsaturated monomers. If the amount of the emulsifier is less than 0.5 parts by weight, the resin fine particles (F) may not be sufficiently stabilized during emulsion polymerization, and the generation of aggregates that cause nozzle clogging may increase. . On the other hand, when the amount of the emulsifier exceeds 2.0 parts by weight, the elution component of the emulsifier increases, and the coating film resistance of the printed matter may deteriorate.

  Examples of the aqueous medium used in the emulsion polymerization of the resin fine particle (F) aqueous dispersion used in the present invention include water, and a hydrophilic organic solvent can be used as long as the object of the present invention is not impaired.

The polymerization initiator used in obtaining the resin fine particle (F) aqueous dispersion used in the present invention is not particularly limited as long as it has the ability to initiate radical polymerization, and known oil-soluble polymerization initiators and water-soluble polymerization initiators can be used. A polymerizable polymerization initiator can be used. The oil-soluble polymerization initiator is not particularly limited, and examples thereof include benzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl hydroperoxide, tert-butyl peroxy (2-ethylhexanoate), and tert-butyl peroxide. Organic peroxides such as oxy-3,5,5-trimethylhexanoate, di-tert-butyl peroxide;
2,2′-azobisisobutyronitrile, 2,2′-azobis-2,4-dimethylvaleronitrile, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 1,1 Mention may be made of azobis compounds such as' -azobis-cyclohexane-1-carbonitrile. These can be used alone or in combination of two or more. These polymerization initiators are preferably used in an amount of 0.1 to 10.0 parts by weight with respect to 100 parts by weight of the ethylenically unsaturated monomer.

In the present invention, it is preferable to use a water-soluble polymerization initiator. For example, ammonium persulfate, potassium persulfate, hydrogen peroxide, 2,2′-azobis (2-methylpropionamidine) dihydrochloride and the like are conventionally known. A thing can be used conveniently. Moreover, when performing emulsion polymerization, a reducing agent can be used together with a polymerization initiator if desired. Thereby, it becomes easy to accelerate the emulsion polymerization rate or to perform the emulsion polymerization at a low temperature. Examples of such a reducing agent include reducing organic compounds such as metal salts such as ascorbic acid, ersorbic acid, tartaric acid, citric acid, glucose, formaldehyde sulfoxylate, sodium thiosulfate, sodium sulfite, sodium bisulfite, Examples include reducing inorganic compounds such as sodium bisulfite, ferrous chloride, Rongalite, thiourea dioxide, and the like. These reducing agents are preferably used in an amount of 0.05 to 5.0 parts by weight with respect to 100 parts by weight of the ethylenically unsaturated monomer. In addition, it can superpose | polymerize also by a photochemical reaction, radiation irradiation, etc. irrespective of an above described polymerization initiator. The polymerization temperature is not less than the polymerization start temperature of each polymerization initiator. For example, in the case of a peroxide-based polymerization initiator, it may be usually about 70 ° C. The polymerization time is not particularly limited, but is usually 2 to 24 hours.
Further, if necessary, sodium acetate, sodium citrate, sodium bicarbonate, etc. as a buffering agent, and octyl mercaptan, 2-ethylhexyl thioglycolate, octyl thioglycolate, stearyl mercaptan, lauryl mercaptan as a chain transfer agent A suitable amount of mercaptans such as t-dodecyl mercaptan can be used.
The resin fine particle (F) aqueous dispersion obtained after the completion of emulsion polymerization can be neutralized with a basic compound. When neutralizing, ammonia or alkylamines such as trimethylamine, triethylamine, butylamine;
Alcohol amines such as 2-dimethylaminoethanol, 2-diethylaminoethanol, diethanolamine, triethanolamine, aminomethylpropanol;
It can be neutralized with a base such as morpholine.

A film forming aid, an antifoaming agent, a leveling agent, a preservative, a pH adjusting agent, a viscosity adjusting agent, and the like can be used in the aqueous inkjet binder resin composition of the present invention as necessary.
The film-forming aid is responsible for the temporary plasticization function that helps the formation of the coating film and evaporates relatively quickly after the coating film is formed, thereby improving the strength of the coating film. Is preferably a solvent having a temperature of 110 to 200 ° C. Specifically, propylene glycol monobutyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol monobutyl ether, diethylene glycol diethyl ether, dipropylene glycol monopropyl ether, carbitol, butyl carbitol, dibutyl carbitol, benzyl alcohol, etc. Is mentioned. Among these, ethylene glycol monobutyl ether and propylene glycol monobutyl ether are particularly preferable because they have a high film forming auxiliary effect in a small amount. These film forming assistants are preferably contained in the binder resin composition in an amount of 0.5 to 15% by weight.

The viscosity modifier may be used in an amount of 1 to 100 parts by weight with respect to 100 parts by weight of the resin fine particles (F). Examples of the viscosity modifier include carboxymethyl cellulose, methyl cellulose, hydroxymethyl cellulose, ethyl cellulose, polyvinyl alcohol, polyacrylic acid (and its salt), oxidized starch, phosphorylated starch, and casein.
The binder resin composition for aqueous inkjet of the present invention can be suitably used for an aqueous inkjet ink containing a pigment dispersion, water, and a hydrophilic solvent.

  In the water-based inkjet ink composition of the present invention, the resin fine particle (F) aqueous dispersion is preferably used in an amount of 1 to 20% by weight, more preferably 2 to 15% by weight in terms of solid content. When the resin fine particle (F) aqueous dispersion is less than 1% by weight in terms of solid content, the binding between the printed material and the pigment particles or between the pigment particles becomes insufficient, and the printed material is rub and water resistant. May decrease. On the other hand, when the resin fine particle (F) aqueous dispersion exceeds 20% by weight in terms of solid content, the viscosity of the ink composition increases, which may adversely affect the ejection properties.

The pigment dispersion may be prepared by dispersing the pigment with a pigment dispersion resin, or a self-dispersing pigment in which a functional group is directly modified on the pigment may be used.
The pigment dispersion resin used at the time of pigment dispersion is preferably a water-soluble resin having a carboxyl group from the viewpoint of stabilization of dispersion in an aqueous system, for example, an acrylic resin, a styrene-acrylic resin, a polyester resin, a polyamide resin, or a polyurethane resin. Can be mentioned. Commercially available products may be used for these resins. As commercially available products, for example, BASF Corp. JONCRYL67, JONCRYL678, JONCRYL586, JONCRYL611, JONCRYL683, JONCRYL690, JONCRYL57J, JONCRYL60J, JONCRYL61J, JONCRYL62J, JONCRYL63J, JONCRYLHPD-96J, JONCRYL501J, JONCRYLPDX-6102B, manufactured by BYK Chemie DISPERBYK, DISPERBYK180, DISPERBYK187 , DISPERBYK190, DISPERBYK191, DISPERBYK194, DISPERBYK2010, DISPERBYK2015, DISPERBYK2090, DISPERBYK2091, DISPERBYK2095, DISPERBYK2155, Zeneca SOLSPERS41000, Sartomer, SMA1000H, SMA1440H, SMA2000H, SMA3000H, etc.

  The pigment dispersion resin is used in an amount of 0.5 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 10 parts by weight of the pigment. If the pigment dispersion resin is less than 0.5 parts by weight with respect to 10 parts by weight of the pigment, the pigment dispersion stability may be lowered, and there may be a problem in the temporal stability of the ink composition. On the other hand, when the pigment dispersion resin exceeds 20 parts by weight with respect to 10 parts by weight of the pigment, the viscosity of the ink composition increases, which may adversely affect the discharge properties.

  As the pigment, for example, an achromatic pigment such as carbon black, titanium oxide, calcium carbonate, or a chromatic organic pigment can be used. Examples of organic pigments include insoluble azo pigments such as toluidine red, toluidine maroon, Hansa Yellow, Benzidine Yellow, and pyrazolone red, soluble azo pigments such as Ritol Red, Helio Bordeaux, Pigment Scarlet, and Permanent Red 2B, alizarin, indanthrone, and thioindigo. Derivatives from vat dyes such as maroon, phthalocyanine organic pigments such as phthalocyanine blue and phthalocyanine green, quinacridone organic pigments such as quinacridone red and quinacridone magenta, perylene organic pigments such as perylene red and perylene scarlet, isoindolinone yellow , Isoindolinone organic pigments such as isoindolinone orange, pyranthrone organic pigments such as pyranthrone red and pyranthrone orange, thioy Digo-based organic pigments, condensed azo-based organic pigments, benzimidazolone-based organic pigments, quinophthalone-based organic pigments such as quinophthalone yellow, isoindoline-based organic pigments such as isoindoline yellow, and other pigments such as flavanthrone yellow and acylamide yellow Nickel azo yellow, copper azomethine yellow, perinone orange, anthrone orange, dianthraquinonyl red, dioxazine violet and the like.

  When organic pigments are exemplified by color index (CI) numbers, C.I. I. Pigment Yellow 12, 13, 14, 17, 20, 24, 74, 83, 8893, 109, 110, 117, 120, 125, 128, 129, 137, 138, 139, 147, 148, 150, 151, 153 154, 155, 166, 168, 180, 185, C.I. I. Pigment orange 16, 36, 43, 51, 55, 59, 61, C.I. I. Pigment Red 9, 48, 49, 52, 53, 57, 97, 122, 123, 149, 168, 177, 180, 192, 202, 206, 215, 216, 217, 220, 223, 224, 226, 227, 228, 238, 240, C.I. I. Pigment violet 19, 23, 29, 30, 37, 40, 50, C.I. I. Pigment blue 15, 15: 1, 15: 3, 15: 4, 15: 6, 22, 60, 64, C.I. I. Pigment green 7, 36, C.I. I. Pigment brown 23, 25, 26, and the like.

  Specific examples of carbon black include “Special Black 350, 250, 100, 550, 5, 4, 4A, 6” “Printex U, V, 140 U, 140 V, 95, 90, 85, 80, 75, 55, manufactured by Degussa. 45, 40, P, 60, L6, L, 300, 30, 3, 35, 25, A, G ", Cabot's" REGAL 400R, 660R, 330R, 250R "," MOGUL E, L ", Mitsubishi Chemical “MA7, 8, 11, 77, 100, 100R, 100S, 220, 230” “# 2700, # 2650, # 2600, # 200, # 2350, # 2300, # 2200, # 1000, # 990, # 980, # 970, # 960, # 950, # 900, # 850, # 750, # 650, # 52, # 50, # 47, # 45, # 4 5L, # 44, # 40, # 33, # 332, # 30, # 25, # 20, # 10, # 5, CF9, # 95, # 260 ”and the like.

  Specific examples of titanium oxide include “Taipeku CR-50, 50-2, 57, 80, 90, 93, 95, 953, 97, 60, 60-2, 63, 67, 58, 58- manufactured by Ishihara Sangyo Co., Ltd. 2, 85 "" Tipekes R-820, 830, 930, 550, 630, 680, 670, 580, 780, 780-2, 850, 855 "," Tipekes A-100, 220 "," Tipekes W-10 "," Tipekes " PF-740, 744 "" TTO-55 (A), 55 (B), 55 (C), 55 (D), 55 (S), 55 (N), 51 (A), 51 (C) " "TTO-S-1, 2", "TTO-M-1, 2", "Titanics JR-301, 403, 405, 600A, 605, 600E, 603, 805, 806, 701, 800, 808" manufactured by Teika "Titanic EN-1, C, 3, 4, 5 ", and the like manufactured by Du Pont" Taipyua R-900,902,960,706,931 ". Organic pigments such as yellow, magenta, cyan and black are usually used in an amount of 0.2 to 15% by weight, preferably 0.5 to 10% by weight in 100% by weight of the water-based inkjet ink. Moreover, in the case of white titanium oxide, it is preferable to mix | blend in the ratio of 5 to 50 weight% normally, Preferably it is 10 to 45 weight%.

The hydrophilic solvent is added as a humectant component for preventing the ink from drying at the nozzle.
As the hydrophilic solvent, for example,
Glycerin;
Ethylene glycol, 1,3-propanediol, propylene glycol, 1,2-butanediol, 1,4-butanediol, pentylene glycol, 1,2-hexanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol Glycol solvents such as tetraethylene glycol;
Lactam solvents such as N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 2-pyrrolidone, ε-caprolactam;
Amide-based solvents such as formamide, N-methylformamide, N, N-dimethylformamide, Idemitsu Examide M-100, and Examide B-100;
Etc.

The hydrophilic solvent is usually used in an amount of 10 to 60% by weight, preferably 20 to 50% by weight, in 100% by weight of the aqueous inkjet ink composition. When the hydrophilic solvent is less than 10% by weight, the dischargeability may deteriorate due to drying of the ink composition at the nozzle. On the other hand, if the hydrophilic solvent exceeds 60% by weight, the printed matter may have insufficient drying properties, which may adversely affect the film resistance such as abrasion resistance, water resistance, and solvent resistance.
Examples of the substrate on which the water-based inkjet ink composition of the present invention can be suitably applied include, for example, a penetrating base material such as fine paper, a non-penetrating base material such as art paper, coated paper, and a polyvinyl chloride sheet. It is done.

  Examples of the ink jet printing method using the aqueous ink jet ink composition of the present invention include an ink jet method having an on-demand type recording head. Examples of the on-demand type include a piezo method, a thermal ink jet method, and an electrostatic method, but the piezo method is most preferable.

  Moreover, when printing using the aqueous inkjet ink composition of the present invention, a heat drying step can be introduced into the printing step as needed for the purpose of reinforcing the drying property and durability of the printed matter. By introducing the heat drying step, the film forming property of the binder resin composition may be improved, and an appropriate heat treatment is preferable. The heat treatment step can be used to such an extent that it does not affect the printing step (inkjet printing speed). For example, the heat treatment step is generally carried out at 40 to 100 ° C. for 1 to 200 seconds.

[Example]
EXAMPLES The present invention will be described more specifically with reference to the following examples. However, the following examples do not limit the scope of rights of the present invention. In the examples, “part” represents “part by weight” and “%” represents “% by weight”.
[Example 1]
A reaction vessel equipped with a stirrer, a thermometer, a dropping funnel and a refluxing vessel was charged with 55 parts of ion exchange water and 0.4 part of Aqualon KH-10 (Daiichi Kogyo Seiyaku Co., Ltd.) as an emulsifier. -54.1 parts of ethylhexyl acrylate, 32.9 parts of methyl methacrylate, 5 parts of styrene, 1.0 part of sodium styrenesulfonate, 1.0 part of acrylamide, 6.0 parts of vinyltriethoxysilane, 30 parts of ion-exchanged water and an emulsifier 5 parts of an emulsion prepared by stirring and mixing 0.6 part of Aqualon KH-10 with a homomixer was added. After raising the internal temperature to 70 ° C. and sufficiently purging with nitrogen, 4.0 parts of a 5% aqueous solution of potassium persulfate and 5.0 parts of a 1% aqueous solution of anhydrous sodium bisulfite were added to initiate polymerization. After the start of the reaction, while maintaining the internal temperature at 75 ° C., take the rest of the emulsion, 1.5 parts of a 5% aqueous solution of potassium persulfate, and 5.8 parts of a 1% aqueous solution of anhydrous sodium bisulfite over 1.5 hours. Then, the mixture was further stirred for 2 hours. After completion of the reaction, the temperature was cooled to 30 ° C., and dimethylaminoethanol was added to adjust the pH to 8.9. Further, the solid content was adjusted to 40% with ion-exchanged water to obtain a resin fine particle (F) aqueous dispersion. The obtained resin fine particles (F) had an average particle size of 110 nm and a glass transition temperature (Tg) of −7 ° C.

[Example 2-7, Comparative Example 1-8]
The compounding compositions shown in Tables 1 and 2 were synthesized in the same manner as in Example 1 to obtain resin fine particle (F) aqueous dispersions. In Example 9, emulsion polymerization was carried out by changing the amount of emulsifier Aqualon KH-10 charged to the reaction vessel to 1.5 parts and in Example 10 to 0.2 parts. As basic physical properties of the obtained resin fine particle (F) aqueous dispersion, the presence / absence of aggregates, glass transition temperature (Tg), and average particle diameter were evaluated.

[Presence or absence of aggregates]
The resin fine particle (F) aqueous dispersion was filtered through a 180 mesh (100 μm) filter cloth, and the amount of aggregate per kg of the resin fine particle (F) aqueous dispersion generated during synthesis was measured. The evaluation criteria are as follows.
◯: Less than 0.1 g Δ: 0.1 g or more, less than 0.3 g x: 0.3 g or more [Average particle diameter]
The resin fine particle (F) aqueous dispersion was diluted with water 500 times, and about 5 ml of the diluted solution was measured by a dynamic light scattering measurement method (measurement apparatus manufactured by Nikkiso Co., Ltd.). The peak of the volume particle size distribution data (histogram) obtained at this time was defined as the average particle size.

[Glass transition temperature (Tg)]
The glass transition temperature (Tg) was measured by DSC (Differential Scanning Calorimeter TA Instruments). About 2 mg of a sample obtained by drying the resin fine particle (F) aqueous dispersion on a aluminum pan, weighed on an aluminum pan, set the aluminum pan on a DSC measurement holder, and an endothermic peak of a chart obtained under a temperature rising condition of 5 ° C./min. The glass transition temperature (Tg) was obtained.
[Average particle size]
The resin fine particle (F) aqueous dispersion was diluted with water 500 times, and about 5 ml of the diluted solution was measured by a dynamic light scattering measurement method (measurement apparatus manufactured by Nikkiso Co., Ltd.). The peak of the volume particle size distribution data (histogram) obtained at this time was defined as the average particle size.

<Production of concentrated pigment dispersion>
[Production of cyan pigment dispersion]
20 parts of pigment [Lionogen Blue 7351 manufactured by Toyo Ink Co., Ltd.], 30 parts of pigment dispersion resin [Jonkrill 61J, 30% aqueous solution of solid content] manufactured by BASF Corporation, 29.3 parts of ion-exchanged water, and defoamer [Surfinol 104E Nissin Chemical Industry Co., Ltd.] 0.5 parts was dispersed with a paint conditioner for 2 hours to obtain a concentrated cyan pigment dispersion.
[Production of magenta pigment dispersion]
A concentrated magenta pigment dispersion was obtained in the same manner as the cyan pigment dispersion, except that the pigment was changed to 20 parts by Fastogen Super Magenta RGT DIC.
[Production of yellow pigment dispersion]
A concentrated yellow pigment dispersion was obtained in the same manner as the cyan pigment dispersion, except that the pigment was changed to 20 parts made by Novoperm Yellow H2G Clariant.
[Production of black pigment dispersion]
A concentrated black pigment dispersion was obtained in the same manner as the cyan pigment dispersion, except that the pigment was changed to 20 parts manufactured by Printex 85 Evonik Degussa.

[Example 13]
To 10 parts of the solid content of the resin fine particles (F) obtained in Example 1, 40 parts of the above-mentioned cyan pigment dispersion, 20 parts of glycerin as a hydrophilic solvent, and 40 parts of 1,3-propanediol, Ion exchange water was added so that the solid content was 12%, and then kneaded to obtain an aqueous inkjet ink composition. The same preparation was performed for each of the magenta pigment dispersion, the yellow pigment dispersion, and the black pigment dispersion to obtain four-color aqueous inkjet ink compositions.
[Examples 14 to 19 and Comparative Examples 9 to 16]
Prepared in the same manner as in Example 13, to obtain a four-color aqueous inkjet ink composition.
[Evaluation of water-based inkjet ink composition]
The four-color water-based inkjet ink composition prepared above was filled in a Color Painter 64SPlus solvent ink inkjet printer manufactured by Seiko I Infotech in an environment of 25 ° C., and an image was printed on fine paper. The ink composition was evaluated for storage stability and dischargeability. After printing, the quality paper was dried at room temperature to obtain a printed matter for evaluation. Using this, various coating film properties such as abrasion resistance, water resistance, and solvent resistance were evaluated. Tables 3 and 4 show the results.

[Storage stability]
About the water-based inkjet ink composition, the change with time of viscosity was evaluated under conditions of 70 ° C. and 2 weeks. The viscosity was measured using a rheometer (AR Instruments 2000 manufactured by TA Instruments). The evaluation criteria are as follows.
A: Change in the viscosity of the ink is less than ± 10% B: Change in the viscosity of the ink is ± 10% or more and less than ± 15% Δ: Change in the viscosity of the ink is ± 15% or more and less than ± 20% × The ink viscosity change is ± 20% or more [Ejectability]
Using the printer described above, the time until drying and nozzle clogging during printing standby (room temperature, no new ink supplied) was evaluated. The term “nozzle clogging” as used herein refers to a state in which ink cannot be printed due to clogging of the nozzles while waiting for printing. If there is no nozzle clogging, it can be said that the discharge property is good. The evaluation criteria are as follows.
◎: No nozzle clogging occurs in 60 minutes ○: Nozzle clogging occurs in 60 minutes Δ: Nozzle clogging occurs in 30 minutes ×: Nozzle clogging occurs in 10 minutes

[Abrasion resistance]
The printed surface of the printed matter for evaluation (quality paper) is scratched on the printed surface by reciprocating 30 times under the condition of a load of 100 / cm ² (contact surface is high quality paper) with a Gakushin abrasion tester (AB-301 manufactured by Tester Sangyo). Evaluated. The evaluation criteria are as follows.
○: There is no scratch Δ: There is a scratch but the substrate is not visible ×: There are many scratches and the substrate is visible
[Water and solvent resistance]
Either water or ethanol was immersed in a cotton swab, and the printed surface of the evaluation printed matter (quality paper) was rubbed about 5 times. The evaluation criteria are as follows.
○: There is no erosion and no ink adheres to the swab. Δ: Ink adheres to the swab but the substrate surface is not visible. ×: Ink adheres to the swab and the substrate surface is also visible.

As shown in Table 3 and Table 4, the aqueous ink-jet ink compositions of Examples 13 to 24 containing the binder resin compositions of Examples 1 to 12 were excellent in ink physical properties (storage stability and ejection properties). The film resistance (rubbing resistance, water resistance, solvent resistance) of the printed matter was also good. On the other hand, the water-based inkjet ink compositions of Comparative Examples 9 to 16 containing the binder resin compositions of Comparative Examples 1 to 8 were poor in both ink physical properties and printed film resistance.

Claims (5)

Aromatic ethylenically unsaturated monomer (A) having no ionic functional group (A) 0 to 20% by weight;
At least one sulfonic acid group-containing ethylenically unsaturated monomer (B) selected from sodium styrene sulfonate, ammonium styrene sulfonate, 2-acrylamide 2-methylpropane sulfonic acid, and sodium allyl sulfonate, or phosphoric acid group-containing Ethylenically unsaturated monomer (C) 0.5-3.0 wt%;
0.1 to 3.0% by weight of a nonionic water-soluble ethylenically unsaturated monomer (D) (except for the case of the following monomer (E));
0.1 to 10% by weight of a crosslinkable ethylenically unsaturated monomer (E);
At least one (meta) selected from a linear or branched alkyl group-containing (meth) acrylate monomer, an alicyclic alkyl group-containing (meth) acrylate monomer, and a fluorinated alkyl group-containing (meth) acrylate monomer ) Acrylate monomers (excluding (A) to (E)) 64 wt% to 99.3 wt%;
Resin fine particles for binder resin for water-based inkjets (F) obtained by emulsion polymerization of ethylenically unsaturated monomers containing. The resin fine particles according to claim 1, wherein the resin fine particles (F) have an average particle diameter of 50 to 200 nm. The resin fine particles according to claim 1 or 2, wherein the resin fine particles (F) have a glass transition temperature of -20 to 40 ° C. The resin fine particles according to any one of claims 1 to 3, wherein the crosslinkable ethylenically unsaturated monomer (E) is an alkoxysilyl group-containing ethylenically unsaturated monomer.   The inkjet ink containing the resin fine particle in any one of Claims 1-4.