JP2002188013A - Method for producing polymer emulsion and ink composition containing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a polymer emulsion effective for improving the printing stability and ejection stability of an ink composition. SOLUTION: The polymer emulsion is produced by carrying out the emulsion polymerization reaction of a mixture of water, a monomer, an emulsifier and a polymerization initiator and adding a water-soluble organic amine to the reaction product to adjust the pH of the product to a desired level.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polymer emulsion, and more particularly to a method for producing a polymer emulsion used in an ink composition.

2. Description of the Related Art Ink jet recording is a method of recording characters and figures on the surface of a recording medium by discharging ink as small droplets from fine nozzles. As the ink for ink-jet recording, those obtained by dissolving various water-soluble dyes in an aqueous medium are generally used. In addition, there is provided an ink in which a pigment is dispersed in an aqueous medium. An ink in which a pigment is dispersed in an aqueous medium has a feature that it is excellent in water resistance and light resistance as compared with a water-soluble dye.

[0003] On the other hand, the characteristics required of the ink for ink jet recording are that the physical properties do not change during long-term storage, that the fine nozzles are not clogged, that the density of the printed matter is high and clear, and that the storability of the printed matter is high. (water resistant,
Good light fastness, etc.). In particular, in the case of pigment-based ink, there is no nozzle clogging during printing or restarting after printing is interrupted, fast drying on a recording medium, and storage stability (that is, the pigment is dispersed stably for a long period of time). Is required to be good.

On the other hand, ejection stability, dispersion stability,
In addition, a pigment ink has been proposed for improving the abrasion resistance. For example, JP-B-62-1426 discloses an ink in which a pigment and a resin emulsion are dispersed in water.
JP-A-5-217668 discloses that a pigment is dispersed in a water-insoluble resin emulsion dispersion.
No. 088 proposes to use an emulsion having a specific film formation temperature, and JP-A-3-60068 and JP-A-4-18462 similarly propose an ink using a resin emulsion. . In addition, Japanese Unexamined Patent Publication No.
JP-A-6-147859, JP-A-56-147860 and JP-B-4-5703 propose aqueous pigment inks using a polymer dispersant and a water-soluble organic solvent. JP-A-3-299234 and JP-A-8-259869 also discuss the use of core-shell type resin particles comprising a core portion and a shell portion surrounding the core portion as ink for ink jet recording.

Further, it has been observed that an ink composition containing a water-soluble polymer sometimes becomes unsuitable for an ink jet recording method due to an increase in the viscosity of the ink composition. Further, in the ink jet recording head, the nozzle plate is treated to be water repellent so that the ink droplets can easily fly from the nozzles.
Ink compositions containing water-soluble polymers generally tend to wet well water-repellent treated nozzle plates. As a result, it was observed that the flight of the ink droplets and the occurrence of ejection failure were observed. Furthermore, when a water-soluble polymer is used, the resulting printed image may have poor water resistance due to its water solubility. Furthermore, it was often observed that the viscosity of the ink increased with the evaporation of the water in the ink, resulting in nozzle clogging.

Further, a polymer emulsion is produced by mixing at least water, an emulsifier, and a polymerization initiator and performing a polymerization reaction under appropriate conditions. The polymer emulsion produced generally exhibits acidic values and may lack its own stability. For this reason, conventionally, ammonia water has been added to the produced polymer emulsion to adjust the pH.

[0007]

SUMMARY OF THE INVENTION The present inventor has now described a method for producing a polymer emulsion, comprising: water, a monomer, an emulsifier,
At least mixing with a polymerization initiator to carry out an emulsion polymerization reaction, and then adding a water-soluble organic amine to a desired pH value to produce a polymer emulsion having improved storage stability. I got the knowledge that I can do it. Furthermore, the present inventors have also found that adding the polymer emulsion produced according to the present invention to an ink composition improves storage stability, clogging reliability, and ejection stability of the ink composition. Obtained. The present invention is based on these findings.

Accordingly, the present invention provides a method for producing a polymer emulsion having improved storage stability,
It is an object of the present invention to provide an ink composition having improved storage stability, clogging reliability, and ejection stability by adding the polymer emulsion.

Thus, the method for producing a polymer emulsion containing polymer fine particles according to the present invention comprises the steps of:
The method comprises at least mixing a monomer, an emulsifier, and a polymerization initiator to carry out an emulsion polymerization reaction, and thereafter, adding a water-soluble organic amine to adjust to a desired pH. .

According to another aspect of the present invention, there is provided an ink composition. The ink composition according to the present invention is an ink composition comprising at least a colorant, a polymer emulsion, water, and a water-soluble organic solvent, wherein the polymer emulsion is manufactured by the manufacturing method according to the present invention. It is.

[0011]

DETAILED DESCRIPTION OF THE INVENTION The definition "polymer emulsion" means an aqueous dispersion in which the continuous phase is water and the dispersed particles are fine polymer particles.
"Polymer emulsion" may also be referred to as resin emulsion. “Polymer fine particles” means fine particles of a polymer component. Specific examples of the polymer component constituting the polymer fine particles include, for example, a styrene- (meth) acrylic acid copolymer, a styrene- (meth) acrylate- (meth) acrylic acid copolymer, and a poly (meth) acrylic acid. Ester, styrene-butadiene copolymer, polybutadiene, acrylonitrile-butadiene copolymer, chloroprene copolymer, polyolefin, polystyrene, polyvinyl acetate, polyamide, ethylene-vinyl acetate copolymer, vinyl acetate-acrylate copolymer , Polyurethane, etc.

A method for producing a polymer emulsion is characterized in that a method for producing a polymer emulsion comprises mixing water, a monomer, an emulsifier, and a polymerization initiator to carry out an emulsion polymerization reaction;
And thereafter, adjusting the pH to a desired pH by adding a water-soluble organic amine. In the present invention, the polymer fine particles forming the dispersed phase of the polymer emulsion are produced by an emulsion polymerization reaction using a monomer (particularly, an unsaturated vinyl monomer), an emulsifier, and a polymerization initiator.

A ) Monomer In the present invention, a monomer, preferably an unsaturated vinyl monomer is used. Specific examples of the unsaturated vinyl monomer include acrylic ester monomers, methacrylic ester monomers, aromatic vinyl monomers, vinyl ester monomers, vinyl cyanide compound monomers, and halogenated ester monomers generally used in emulsion polymerization. Monomers,
Olefin monomers and diene monomers are mentioned. Further, as specific examples thereof, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-amyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, decyl acrylate, Dodecyl acrylate, octadecyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, glycidyl acrylate,
Acrylates such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n
-Butyl methacrylate, isobutyl methacrylate,
Methacrylates such as n-amyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, decyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, glycidyl methacrylate, and the like; Vinyl esters such as vinyl acetate; vinyl cyanide compounds such as acrylonitrile and methacrylonitrile; halogenated monomers such as vinylidene chloride and vinyl chloride; styrene, 2-methylstyrene, vinyl toluene,
Aromatic vinyl monomers such as t-butylstyrene, chlorostyrene, vinylanisole and vinylnaphthalene; olefins such as ethylene, propylene and isopropylene; dienes such as butadiene and chloroprene; vinyls such as vinyl ether, vinyl ketone and vinylpyrrolidone Monomers. For a monomer having no carboxyl group, the use of an unsaturated vinyl monomer having a carboxyl group is essential, and preferred examples thereof include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, and maleic acid. The use of methacrylic acid is preferred.

Further, in the present invention, it is preferable to have a structure in which a molecule derived from the above monomer is crosslinked by a crosslinkable monomer having two or more polymerizable double bonds. Examples of the crosslinkable monomer having two or more polymerizable double bonds include polyethylene glycol diacrylate, triethylene glycol diacrylate, and 1,3.
-Butylene glycol diacrylate, 1,6-butylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, 1,9-nonanediol diacrylate, polypropylene glycol diacrylate, 2,2′-bis (4-acryloxypropyloxyphenyl) propane,
Diacrylate compounds such as 2,2'-bis (4-acryloxydiethoxyphenyl) propane; triacrylate compounds such as trimethylolpropane triacrylate, trimethylolethane triacrylate, and tetramethylol methane triacrylate; ditrimethylol tetraacrylate Tetraacrylate compounds such as tetramethylolmethanetetraacrylate and pentaerythritol tetraacrylate; hexaacrylate compounds such as dipentaerythritol hexaacrylate;
Ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate,
1,4-butylene glycol dimethacrylate, 1,6
-Hexanediol dimethacrylate, neopentyl glycol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, polybutylene glycol dimethacrylate,
Dimethacrylate compounds such as 2,2'-bis (4-methacryloxydiethoxyphenyl) propane; trimethacrylate compounds such as trimethylolpropane trimethacrylate and trimethylolethane trimethacrylate; methylenebisacrylamide and divinylbenzene.

Further, by adding an acrylamide or a hydroxyl group-containing monomer in addition to the above-mentioned monomer, the printing stability can be further improved. Examples of acrylamides include acrylamide and N,
N'-dimethylacrylamide is exemplified. Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 2-hydroxyethyl acrylate.
-Hydroxyethyl methacrylate and 2-hydroxypropyl methacrylate, and these can be used alone or in combination of two or more.

B) Emulsifiers, polymerization initiators, and other components Emulsifiers include anionic surfactants such as alkyl allyl sulfonate or sulfate, alkyl sulfonate or sulfate, dialkyl sulfosuccinate, and polyoxyethylene. Nonionic surfactants such as nonylphenyl ether, polyoxyethylene stearic acid ester, polyoxyethylene alkyl allyl ether, and sorbitan monolaurate are included. Examples of the polymerization initiator include potassium persulfate and ammonium persulfate. Other components include a polymerization regulator,
Examples include a chain transfer agent and a molecular weight regulator.

C) Emulsion polymerization and reaction conditions The polymer fine particles are produced by mixing a monomer, an emulsifier, a polymerization initiator, and other optional components and performing an emulsion polymerization reaction. The amounts of these components added can be determined as appropriate. Further, the above-mentioned components are put into a reaction vessel and mixed to carry out an emulsion polymerization reaction. The emulsion polymerization reaction temperature is 60 to 90
° C, preferably about 70 to 80 ° C.

According to a preferred embodiment of the present invention, it is preferable that water, a monomer, an emulsifier, a polymerization initiator, and other optional components are supplied to one reaction vessel and mixed to cause an emulsion polymerization reaction. According to this reaction, polymer fine particles dispersed in water can be obtained. In the present invention, it is preferable to stir throughout the reaction as well as when mixing the above-mentioned components or when performing an emulsion polymerization reaction.

The polymer fine particles having a core-shell structure described below are produced by a known method, generally by multi-stage emulsion polymerization or the like. For example, JP-A-4-76
It can be manufactured by the method disclosed in JP-A-004-004. Examples of the unsaturated vinyl monomer used for the polymerization include those described above.

Further, the introduction of the epoxy group into the above-mentioned core portion is carried out by converting an unsaturated vinyl monomer having an epoxy group into
Glycidyl acrylate, glycidyl methacrylate,
Examples include a method of copolymerizing allyl glycidyl ether or the like with another unsaturated vinyl monomer, or a method of simultaneously adding an epoxy compound when preparing core particles by polymerizing one or more unsaturated vinyl monomers to form a composite. Can be. The former method is preferred from the viewpoint of easiness of polymerization and polymerization stability.

D) pH Adjustment In the present invention, the polymer emulsion obtained by the above emulsion polymerization is adjusted to a desired pH by adding a water-soluble organic amine. As the water-soluble organic amine, an amino alcohol is preferable, and a tertiary amino alcohol is more preferable. As specific examples of the tertiary amino alcohol, those represented by the following formula (I) or (II) are preferable, and one or a mixture of two or more thereof is preferably used.

[0022]

Embedded image [In the above formula (I), R represents an alkyl group (preferably linear or branched, having 1 to 13 carbon atoms, preferably 1
An alkyl group which is the same as or different from an alkyl group, an aryl group (preferably a phenyl group), or a hydrogen atom.
Represents an integer of 3 to 3]

[0023]

Embedded image [In the above formula (II), R represents an alkyl group (preferably linear or branched, having 1 to 13, preferably 1 carbon atoms)
An alkyl group which is the same as or different from an alkyl group, an aryl group (preferably a phenyl group), or a hydrogen atom.
Represents an integer of 3 to 3]

Further, preferred specific examples of the tertiary amino alcohol include N, N-diethanolamine and N, N-diethanolamine.
N-dimethylethanolamine, N- (2-aminoethyl) ethanolamine, N-methyldiethanolamine, N, N-dibutylethanolamine, N-methylethanolamine, isopropanolamine, monoethanolamine, diethanolamine, triethanolamine, morpholine And the like, and more preferably triethanolamine and isopropanolamine.

When the desired pH is adjusted by adding a water-soluble organic amine, the pH is specifically adjusted to be in the range of about 7 to 10, preferably in the range of about 7 to 9. Therefore, the amount of the water-soluble organic amine to be added is such that the polymer emulsion falls within the above-mentioned pH range.

E) Production Method The production method of the polymer emulsion is briefly described below. Water, emulsifier, charged with a polymerization initiator, adjusted to a predetermined temperature stirrer, reflux condenser,
An emulsified polymerizable monomer is added to a reaction vessel equipped with a dropping device, a thermometer, and the like, and reacted to obtain a polymer emulsion. To this, a water-soluble organic amine is added so as to obtain a desired pH. This produces a polymer emulsion according to the invention.

Polymer emulsion

The polymer emulsion produced according to the present invention has a ratio of polymer fine particles to water of 1: 1 to 4
And preferably in the range of about 1: 1-3.
According to a preferred embodiment of the present invention, the polymer fine particles are preferably composed of a polymer component having both a hydrophilic portion and a hydrophobic portion. Further, the average molecular weight of the polymer fine particles is about 10,000 or more. The average particle diameter of the polymer fine particles is preferably about 400 nm or less, more preferably about 10 to 200 nm.

According to a preferred embodiment of the present invention, the glass transition point of the polymer fine particles is about 30 ° C. or less, preferably 2 ° C. or less.
It is preferably about 5 ° C. or less, more preferably about 20 ° C. or less.

According to a preferred embodiment of the present invention, the minimum film forming temperature of the polymer emulsion is about 30 ° C. or lower, preferably about room temperature (about 25 ° C.) or lower, more preferably about 20 ° C. or lower. preferable. If the film formation of the polymer fine particles can be performed at 30 ° C. or less, the film formation on the printing surface automatically proceeds at room temperature or less without heating and drying the printed recording medium, and the pigment is firmly attached to the recording medium. It is preferable because the toner is fixed to the toner. Here, the "minimum film forming temperature" means that a polymer emulsion obtained by dispersing polymer fine particles in water is thinly cast on a metal plate such as aluminum, and a transparent continuous film is formed when the temperature is increased. Means the lowest temperature at which In a temperature region lower than the minimum film forming temperature, a white powder is formed.

"Film-forming property" means that when a polymer fine particle is dispersed in water to form a polymer emulsion, a water component which is a continuous phase of the polymer emulsion is evaporated to form a polymer film. Means that The ink composition to which the polymer particles are added,
When the water or the aqueous organic solvent is removed from the periphery of the polymer fine particles, the polymer film has the property of being formed in the same manner.

According to a preferred embodiment of the present invention, the polymer
The fine particles have a carboxyl group on the surface and
Highly cohesive with valent metal salts is preferred
No. Specifically, the polymer fine particles have a particle size of 0.1.
3 volumes of polymer emulsion having 1% by weight,
1 volume of an aqueous solution of a divalent metal salt having a concentration of 1 / l
At this time, the transmittance of light having a wavelength of 700 nm is 50% of the initial value.
1 × 10 ⁴ Seconds or less (preferably 1 × 10³
Seconds or less, more preferably 1 × 10²Seconds)
It has an aggregating property with various divalent metal salts. polymer
When the fine particles come into contact with divalent metal ions, they aggregate and float.
To reduce the clarity of the solution. The amount of this suspended matter generated is
It is measured with a transmittance of. Where the divalent metal ion and
Is Ca²⁺, Cu²⁺, Ni²⁺, Mg²⁺, Zn²⁺,
Ba²⁺And form an anion that forms a salt with it.
The Cl^- , NO^3- , I^- , Br^- , ClO^3-
And CH₃COO^-Is raised. Such high stiffness
Concentration is due to the fact that polymer particles
It is considered to be due to having a boxyl group.
Polycarbonate with a large amount of carboxyl groups on its surface as described above
The ink composition comprising the rimer fine particles is subjected to a water-repellent treatment.
To the nozzle plate of the ink jet recording head
Not compatible. Therefore, conventionally, an ink set containing a resin
The ink composition, which has been a problem in
Wet the plate well, resulting in flying bends of ink drops
And that the occurrence of poor discharge is effectively prevented.
Have a point. Also has a relatively large amount of carboxyl groups
The use of fine polymer particles provides better abrasion and
Aqueous is achieved. Furthermore, this polymer fine particle surface
Excellent storage stability due to high hydrophilicity
It also has the advantage that the property is obtained.

According to a preferred embodiment of the present invention, the polymer
Polymer emulsified with fine particles dispersed in water at a concentration of 10% by weight
The contact angle of lujon on the Teflon plate is about 70 ° or more,
More preferably, it is preferably about 80 ° or more.
Further, polymer fine particles were dispersed in water at a concentration of 35% by weight.
The surface tension of the polymer emulsion is 40 × 10
^-3N / m (40 dyne / cm, 20 ° C.))
Preferably 50 × 10^-3It is preferably about N / m or more.
Good. By using polymer fine particles as described above,
Therefore, in the ink jet recording method, the flight music is more
Can be prevented, and good printing can be performed.

According to another preferred embodiment of the present invention, the polymer fine particles comprise 1 to 10% by weight of a structure derived from an unsaturated vinyl monomer having a carboxyl group, and have two polymerizable double bonds. It is preferable to have a structure crosslinked by the crosslinkable monomer having the above, and to contain 0.2 to 4% by weight of a structure derived from the crosslinkable monomer. Due to the use of a cross-linkable polymer obtained by copolymerizing cross-linkable monomers having two or more polymerizable double bonds, more preferably three or more at the time of polymerization and three-dimensionally cross-linking, the nozzle plate surface may be changed depending on the ink composition. Further, it becomes difficult to get wet, the bending of the flight can be further prevented, and the ejection stability can be further improved.

In the present invention, a polymer particle having a single particle structure can be used. On the other hand, in the present invention, it is also possible to use polymer fine particles having a core-shell structure composed of a core portion and a shell portion surrounding the core portion. In the present invention, the “core-shell structure”
It means "a form in which two or more kinds of polymers having different compositions exist in a phase-separated state in a particle". Therefore, not only a form in which the shell part completely covers the core part but also a part in which the core part is partially covered may be used. Further, a part of the shell polymer may form a domain or the like in the core particle. Further, a layer having a multilayer structure of three or more layers including layers having different compositions may be further provided between the core part and the shell part.

According to a preferred embodiment of the present invention, it is preferable that the core is formed of a polymer having an epoxy group and the shell is formed of a polymer having a carboxyl group. The epoxy group and the carboxyl group have the property of reacting with each other, but these two groups are present separately in the core and the shell. Due to the decrease in water or the water-soluble organic solvent, the polymer fine particles coalesce and are deformed by the pressure accompanying film formation. Thereby, the epoxy group of the core and the carboxyl group of the shell are combined to form a network structure. Thereby, there is obtained an advantage that a film having higher strength can be formed. The amount of the unsaturated vinyl monomer having an epoxy group is 1 to 10% by weight.
It is preferred that Here, the reaction between some epoxy groups and carboxyl groups before film formation is permissible in the present invention as long as the film-forming ability is not lost. In the present invention, the property of causing a reactive functional group to coexist in such polymer fine particles and reacting the groups during film formation without adding a curing agent to form a network structure is referred to as "self-crosslinking property". Call.

Ink Composition The ink composition of the present invention comprises at least a colorant, fine polymer particles, water and a water-soluble organic solvent, and the fine polymer particles are produced by the above-mentioned production method. Characterized in that it is used in the form of a prepared polymer emulsion. The ink composition according to the present invention is used for a recording method using the ink composition. Examples of the recording method using the ink composition include an ink jet recording method, a recording method using a writing instrument such as a pen, and various other printing methods. In particular, the ink composition according to the present invention is preferably used for an ink jet recording method.

A ) Polymer Emulsion As the polymer emulsion, the polymer emulsion produced by the production method according to the present invention described above is used.
The content of the polymer emulsion can be appropriately determined depending on the content of the polymer fine particles constituting the polymer emulsion in the ink composition. Therefore, the content of the polymer particles is 0.1 to 3 with respect to the ink composition.
It is about 0% by weight, preferably 5 to 30% by weight.

B) Colorant The ink composition of the present invention uses a pigment as a colorant. Pigments are excellent colorants in terms of light resistance and water resistance.
The pigment is not particularly limited, and any of an inorganic pigment and an organic pigment can be used. As the inorganic pigment, in addition to titanium oxide and iron oxide, carbon black produced by a known method such as a contact method, a furnace method, and a thermal method can be used. Organic pigments include azo dyes (including azo lakes, insoluble azo pigments, condensed azo pigments, chelated azo pigments, etc.), and polycyclic pigments (for example, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazines) Pigments, thioindigo pigments, isoindolinone pigments, quinofuralone pigments, etc., dye chelates (eg, basic dye chelates, acid dye chelates, etc.), nitro pigments, nitroso pigments, aniline black and the like can be used.

As carbon black used as black ink, Mitsubishi Chemical No. 2300, No. 900, MCF88, No. 3
3, No.40, No.45, No.52, MA7, MA8, MA100, No2200B etc.
Columbia Raven5750, Raven5250, Raven5000, Rav
en3500, Raven1255, Raven700, etc.
gal 400R, Regal 330R, Rega l660R, Mogul L, Monarch 70
0, Monarch 800, Monarch 880, Monarch 900, Monarch
1000, Monarch 1100, Monarch 1300, Monarch 1400 etc. are Degussa Color Black FW1, Color BlackFW2,
Color Black FW2V, Color Black FW18, Color Black F
W200, Color BlackS150, Color Black S160, Color Bla
ck S170, Printex 35, Printex U, Printex V, Printe
x 140U, Special Black 6, Special Black 5, Special
Black 4A, Special Black 4, etc. can be used. CI Pigment Yellow is used as a pigment for yellow ink.
1, CIPigment Yellow 2, CIPigment Yellow 3,
CIPigment Yellow 12, CIPigmentYellow 13, CIP
igment Yellow 14C, CIPigment Yellow 16, CIPigm
ent Yellow 17, CIPigment Yellow 73, CIPigment
Yellow 74, CIPigment Yellow 75, CIPigment Yell
ow 83, CIPigment Yellow 93, CIPigment Yellow9
5, CIPigment Yellow97, CIPigment Yellow 98, C.
I. Pigment Yellow114, CIPigment Yellow128, CIPi
gment Yellow129, CIPigment Yellow151, CIPigmen
t Yellow 154 and the like. Pigments used for magenta ink include CI Pigment Red 5, CI Pigment
ment Red 7, CIPigment Red 12, CIPigment Red 48
(Ca), CIPigment Red 48 (Mn), CIPigment Red 57 (C
a), CIPigment Red 57: 1, CIPigment Red112, CI
Pigment Red 123, CIPigment Red 168, CIPigment
Red 184, CIPigment Red 202 and the like. Furthermore, CI Pigm is a pigment used for cyan ink.
ent Blue 1, CIPigment Blue 2, CIPigment Blue
3, CIPigment Blue 15: 3, CIPigment Blue 15:34,
CIPigment Blue 16, CIPigment Blue 22, CIPigm
ent Blue 60, CIVat Blue 4 and CIVat Blue 60.

The content of the pigment is 0.1 to the ink composition.
The range is preferably about 1 to 25% by weight, more preferably 1 to 25% by weight.
About 15% by weight. The particle size of the pigment is 1
It is preferably 0 μm or less, and more preferably 0.1 μm or less.

In one preferred embodiment of the present invention, it is preferable to use a pigment which can be dispersed in water without a dispersant. This pigment has a carbonyl group,
The surface is treated such that at least one functional group of a carboxyl group, a hydroxyl group, or a sulfone group or a salt thereof is bonded, and can be dispersed in water without a dispersant. Specifically, for example, a functional group or a molecule containing a functional group is applied to the surface of carbon black by physical treatment such as vacuum plasma or chemical treatment (eg, oxidation treatment with hypochlorous acid, sulfonic acid, or the like). It can be obtained by grafting. In the present invention, the functional groups grafted to one carbon black particle may be single or plural. The type and the degree of the functional group to be grafted may be appropriately determined in consideration of the dispersion stability in the ink, the color density, the drying property on the front surface of the inkjet head, and the like.

The pigment preferably used in the present invention can be obtained, for example, by the method described in JP-A-8-3498. Carbon black treated by the method described in this publication has a high surface active hydrogen content of 1.5 to 2.5 mmol / g. As a result, they disperse very well in water. It is also possible to use a commercial product as the pigment, and a preferred example is Microjet CW manufactured by Orient Chemical Industries, Ltd.
1 or 2.

According to another preferred embodiment of the present invention, the pigment is preferably added to the ink as a pigment dispersion liquid dispersed in an aqueous medium with a dispersant. As a dispersant used for preparing a pigment dispersion, a dispersant generally used for preparing a pigment dispersion, for example, a polymer dispersant or a surfactant can be used. It will be apparent to those skilled in the art that the surfactant contained in this pigment dispersion will also function as the surfactant of the ink composition.

Preferred examples of the polymer dispersant include natural polymers, and specific examples thereof include proteins such as glue, gelatin, casein and albumin; natural rubbers such as gum arabic and tragacanth; and savonin and the like. Glucosides; alginic acid and alginic acid derivatives such as alginic acid propylene glycol ester, alginic acid triethanolamine and ammonium alginate; methylcellulose, carboxymethylcellulose,
Examples include cellulose derivatives such as hydroxyethyl cellulose and ethyl hydroxy cellulose. Further, preferred examples of the polymer dispersant include synthetic polymers, such as polyvinyl alcohols, polyvinylpyrrolidones, polyacrylic acid, acrylic acid-acrylonitrile copolymer, potassium acrylate-acrylonitrile copolymer, and vinyl acetate. -Acrylic resins such as acrylic ester copolymers and acrylic acid-acrylic ester copolymers; styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, and styrene-methacrylic acid-acrylic acid ester copolymers Styrene-acrylic resins such as styrene-α-methylstyrene-acrylic acid copolymer, styrene-α-methylstyrene-acrylic acid-acrylate copolymer; styrene-maleic acid copolymer, styrene-maleic anhydride Copolymer, vinyl naphthalene-acrylic acid copolymer , Vinylnaphthalene-maleic acid copolymer, and vinyl acetate-ethylene copolymer, vinyl acetate-fatty acid vinyl-ethylene copolymer, vinyl acetate-maleic acid ester copolymer, vinyl acetate-crotonic acid copolymer, And vinyl acetate-based copolymers such as vinyl acetate-acrylic acid copolymers and salts thereof. Among them, a copolymer of a monomer having a hydrophobic group and a monomer having a hydrophilic group, and a polymer composed of a monomer having both a hydrophobic group and a hydrophilic group in a molecular structure are preferable. The above salts include diethylamine, ammonia,
Ethylamine, triethylamine, propylamine, isopropylamine, dipropylamine, butylamine,
Salts with isobutylamine, triethanolamine, diethanolamine, aminomethylpropanol, morpholine and the like can be mentioned. These copolymers preferably have a weight average molecular weight of 3,000 to 30,000,
More preferably, it is 5,000 to 15,000.

Examples of preferred surfactants as dispersants include alkane sulfonates,
a-Sulfonate type such as olefin sulfonate (AOS), alkylbenzene sulfonate (ABS), alkyl naphthalene sulfonate, acylmethyl taurate, dialkyl sulfosuccinate; alkyl sulfate ether salt, sulfated oil, sulfuric acid Sulfuric acid ester type such as polyolefin ethylene, polyoxyethylene alkyl ether sulfate salt, polyoxyethylene alkyl phenyl ether sulfate salt; carboxylic acid type such as fatty acid salt (soap), alkyl sarcosine salt; alkyl phosphate ester salt, poly Phosphate esters such as oxyethylene alkyl ether phosphate, polyoxyethylene alkyl phenyl ether phosphate and monoglycerite phosphate; anionic surfactants represented by; Pyridium types such as beam salts; amino acid type, such as an alkyl amino acid salts, betaine type, such as an alkyl dimethyl betaine; zwitterionic surfactants typified by such further include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ether,
Ethylene oxide addition type such as polyoxyethylene alkyl ester and polyoxyethylene alkyl amide; polyol ester type such as glycerin alkyl ester, sorbitan alkyl ester and sugar alkyl ester; polyol ether type such as polyhydric alcohol alkyl ether; alkanolamine fatty acid amide Alkanolamide-type nonionic surfactants and the like. The addition amount of these dispersants is preferably in the range of 1 to 50% by weight, more preferably 5 to 30% by weight, based on the pigment.

C) water, water-soluble organic solvents and other
Ingredients The solvent of the ink composition according to the invention uses water and a water-soluble organic solvent as main components.

According to a preferred embodiment of the present invention, the ink composition used in the present invention preferably contains a wetting agent composed of a high-boiling organic solvent as the water-soluble organic solvent.
Preferred examples of the high boiling organic solvent include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, propylene glycol, butylene glycol,
2,6-hexanetriol, thioglycol, hexyleneglycol, glycerin, trimethylolethane,
Polyhydric alcohols such as trimethylolpropane; ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene Alkyl ethers of polyhydric alcohols such as glycol monobutyl ether; 2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, triethanolamine and the like.

Among them, it is preferable to use a water-soluble organic solvent having a boiling point of 180 ° C. or higher. Use of a water-soluble organic solvent having a boiling point of 180 ° C. or higher results in water retention and wettability of the ink composition. As a result, even if the ink composition is stored for a long period of time, there is no aggregation or increase in viscosity of the pigment, and excellent storage stability can be realized. Further, an ink composition that maintains fluidity and redispersibility for a long time even when left in an open state (a state where it is exposed to air at room temperature) can be realized. Further, in the ink jet recording method, high ejection stability can be obtained without clogging of the nozzle at the time of restart during printing or after interruption of printing.

Examples of the water-soluble organic solvent having a boiling point of 180 ° C. or higher include ethylene glycol (boiling point: 197 ° C .; hereinafter, the boiling point is shown in parentheses) and propylene glycol (187).
° C), diethylene glycol (245 ° C), pentamethylene glycol (242 ° C), trimethylene glycol (214 ° C), 2-butene-1,4-diol (235 ° C).
° C), 2-ethyl-1,3-hexanediol (243
° C), 2-methyl-2,4-pentanediol (197
C), N-methyl-2-pyrrolidone (202 C), 1,
3-dimethyl-2-imidazolidinone (257 to 260
C), 2-pyrrolidone (245 C), glycerin (29
0 ° C.), tripropylene glycol monomethyl ether (243 ° C.), dipropylene glycol monoethyl glycol (198 ° C.), dipropylene glycol monomethyl ether (190 ° C.), dipropylene glycol (2
32 ° C.), triethylene glycol monomethyl ether (249 ° C.), tetraethylene glycol (327
° C), triethylene glycol (288 ° C), diethylene glycol monobutyl ether (230 ° C), diethylene glycol monoethyl ether (202 ° C), and diethylene glycol monomethyl ether (194 ° C). Those having a boiling point of 200 ° C. or higher are preferred.
These water-soluble organic solvents can be used alone or in combination of two or more.

The content of these high-boiling organic solvents is preferably about 0.01 to 10% by weight, more preferably about 0.1 to 5% by weight, based on the ink composition.

In the present invention, a low boiling organic solvent may be contained. Preferred specific examples thereof include methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butanol, sec-butanol and t-butanol.
ert-butanol, iso-butanol, n-pentanol and the like. Particularly, a monohydric alcohol is preferable. The amount of the low-boiling organic solvent to be added is 0.5 to the ink composition.
The range is preferably about 10% by weight, more preferably 1.
It is in the range of 5-6% by weight.

The ink composition of the present invention can contain a tertiary amine or an alkali hydroxide. The addition of a tertiary amine results in wettability. Further, the addition of the tertiary amine and the alkali hydroxide brings about dispersion stabilization of the pigment and the polymer fine particles in the ink composition in the ink.

Examples of the tertiary amine include trimethylamine, triethylamine, triethanolamine, dimethylethanolamine, diethylethanolamine, triisopropenolamine, butyldiethanolamine and the like. These may be used alone or in combination. The amount of the tertiary amine to be added is about 0.1 to 10% by weight, more preferably about 0.5 to 5% by weight, based on the ink composition.

Examples of the alkali hydroxide include potassium hydroxide, sodium hydroxide and lithium hydroxide, and the amount of the alkali hydroxide is about 0.01 to 5% by weight based on the ink composition, and more preferably. The range is preferably about 0.05 to 3% by weight.

[0056] The ink composition according to the present invention may further contain a surfactant. Specific examples of the surfactant include anionic surfactants (for example, sodium dodecylbenzenesulfonate, sodium laurate, ammonium salts of polyoxyethylene alkyl ether sulfate, etc.), nonionic surfactants (for example, polyoxyethylene alkyl Ether, polyoxyethylene alkyl ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkylamine, polyoxyethylene alkylamide, etc., amphoteric surfactant (for example, N, N-dimethyl-N -Alkyl-N-carboxymethylammonium betaine, N, N-dialkylaminoalkylenecarboxylate, N, N, N-trialkyl-N-sulfoalkyleneammonium betaine, N N
-Dialkyl-N, N-bispolyoxyethylene ammonium sulfate betaine, 2-alkyl-1-carboxymethyl-1-hydroxyethylimidazolinium betaine) and the like. These can be used alone or in combination of two or more.

The addition amount of these surfactants is in the range of 0.01 to 10% by weight, preferably 0.1 to 5% by weight, based on the ink composition.

According to a preferred embodiment of the present invention, the ink composition according to the present invention preferably further comprises a glycol ether and / or an acetylene glycol-based surfactant.

The glycol ethers used in the present invention are also used as the above-mentioned water-soluble organic solvents. Specific examples thereof include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, and the like. Ethylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-propyl ether, ethylene glycol mono-i
so-propyl ether, diethylene glycol mono-
iso-propyl ether, ethylene glycol mono-
n-butyl ether, ethylene glycol mono-t-butyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol mono-n-butyl ether, diethylene glycol mono-t-butyl ether, 1-methyl-1-methoxybutanol, propylene glycol monomethyl ether, propylene Glycol monoethyl ether, propylene glycol mono-t-
Butyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-iso-propyl ether, propylene glycol mono-n-butyl ether, dipropylene glycol mono-n-butyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, Examples thereof include dipropylene glycol mono-n-propyl ether and dipropylene glycol mono-iso-propyl ether, and these can be used alone or as a mixture of two or more.

In the present invention, it is preferable that the composition contains an acetylene glycol-based surfactant. By this addition, the permeability of the ink composition to the recording medium can be increased, and printing with little bleeding on various recording media can be expected.
Preferred specific examples of the acetylene glycol-based surfactant used in the present invention include a compound represented by the following formula (III).

Embedded image [In the above formula, 0 ≦ m + n ≦ 50, R ¹ , R ² , R ³ , and R ⁴ are each independently an alkyl group (preferably a linear or branched alkyl group having 6 or less carbon atoms. )

Among the compounds represented by the above formula (III), particularly preferred are 2,4,7,9-tetramethyl-5-decyne-4,7-diol and 3,6-dimethyl-4-octyne -3,6-diol, 3,5-dimethyl-1-hexyn-3-ol and the like. Commercially available products can be used as the acetylene glycol-based surfactant represented by the above formula (III), and specific examples thereof include Surfynol 104, 82, 465, 485, and T
G (all available from Air Products and Chemicals. Inc.), Olfin STG, Olfin E101
0 (the trade name of Nissin Chemical Co., Ltd.). The addition amount of the surfactant is 0.01 to 10 with respect to the ink composition.
%, More preferably about 0.1 to 5% by weight.

D) Sugar or Sugar Derivative According to a preferred embodiment of the present invention, the ink composition preferably comprises a sugar or a sugar derivative. Addition of sugar or a derivative of sugar brings water retention to the ink composition.

Examples of sugars include monosaccharides, disaccharides, oligosaccharides (including trisaccharides and tetrasaccharides) and polysaccharides, preferably glucose, mannose, fructose, ribose, xylose, arabinose, galactose, aldone. Acid, glucitol, (sorbitol), maltose, cellobiose, lactose, sucrose, trehalose, maltotriose, and the like. Here, the polysaccharide means a sugar in a broad sense, and is used to include a substance widely existing in nature such as alginic acid, α-cyclodextrin, and cellulose. Derivatives of these sugars include reducing sugars of the above-mentioned saccharides [(for example, sugar alcohol (general formula HOCH ₂ (CHOH) _n )
CH ₂ OH (where n is an integer of 2 to 5)], oxidized sugars (eg, aldonic acid, uronic acid, etc.), amino acids, thio sugars and the like. Particularly, sugar alcohols are preferable, and specific examples include maltitol and sorbitol. The amount of sugar or sugar derivative added is preferably in the range of about 0.1 to 40% by weight, and more preferably in the range of about 2.5 to 20% by weight, based on the ink composition.

E) Glycerin According to a preferred embodiment of the present invention, the ink composition containing the pigment preferably contains glycerin. Addition of glycerin effectively prevents drying of the ink composition on the front surface of the nozzle of the recording head and prevents clogging of the nozzle. Glycerin is added in an amount of 5 to 40% by weight based on the weight of the ink composition.
In the range, preferably about 10 to 20% by weight.

The ink composition according to the present invention further comprises an anti-clogging agent for a nozzle, a preservative, an antioxidant, a conductivity adjuster, a pH adjuster, a viscosity adjuster, a surface tension adjuster, an oxygen absorber and the like. can do.

F) Production of Ink Composition The ink composition according to the present invention can be produced by dispersing and mixing the above components by an appropriate method. A colorant, an aqueous solvent and other components are mixed with an appropriate dispersing machine (for example, a ball mill, a sand mill, an attritor, a roll mill, an agitator mill, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a jet mill, an ang mill). Prepare a uniform dispersion. next,
Water, a water-soluble organic solvent, sugar, a pH adjuster, a preservative, a fungicide and the like are added and sufficiently dissolved to prepare an ink solution. After sufficiently stirring, the mixture is filtered to remove coarse particles and foreign substances that cause clogging, thereby obtaining a target ink composition.

Ink Jet Recording Method The recording method according to the present invention comprises a step of recording an image by attaching an ink composition onto a recording medium. In the present invention, the above-described ink composition can be used.

In the present invention, as the recording medium, any of those having absorptivity to the ink composition such as paper and those substantially non-absorbing to the ink composition are suitably used. Specific examples of the recording medium to which the inkjet recording method according to the present invention is applicable include polyethylene terephthalate, polycarbonate, polypropylene, polyethylene, polysulfone, ABS resin, a plastic sheet based on polyvinyl chloride, brass, iron, aluminum, Water-repellent to recording media that has been subjected to a metal coating treatment on a metal surface such as SUS or copper or a non-metallic substrate by vapor deposition or the like, a recording medium that has been subjected to a water-repellent treatment using paper as a substrate, or a fiber surface such as cloth A recording medium that has been processed, etc.
A recording medium made of a so-called ceramic material obtained by firing an inorganic material at a high temperature may be used.

[0069]

The present invention will be described in detail with reference to the following examples, but the present invention is not limited to the contents of the examples. Preparation of Polymer Emulsion A polymer emulsion containing polymer fine particles as dispersed particles was prepared by the following method. Various properties of the obtained polymer emulsion were measured by the following methods.

Preparation Method of Polymer Emulsion 0.5 parts by weight of potassium persulfate and 80 parts by weight of pure water were added to a flask equipped with a stirrer, a thermometer, a reflux condenser, and a dropping funnel. The internal temperature was heated to 70 ° C. On the other hand, each component as shown in the following Tables 1 and 2 (in Tables 1 and 2, the unit of numerical values represents parts by weight) was mixed and stirred to prepare an emulsion. The emulsion was gradually dropped into the flask over 3 hours using a dropping funnel to carry out an emulsion polymerization reaction. The resulting polymer emulsion was adjusted to a solid content of 40% by weight and pH 8 by adding triethanolamine (example) or ammonia (comparative example) to form a polymer emulsion. The obtained polymer emulsion had a minimum film formation temperature of about 20 ° C. and an average particle diameter of 150 nm.

Measurement of minimum film formation temperature Measurement was performed using a minimum film formation temperature measuring apparatus. When the temperature gradient on the aluminum sample plate reached equilibrium, the polymer emulsion was thinly spread and dried. When the surface of the sample plate is observed after drying is completed, a transparent continuous film is formed in a temperature region equal to or higher than the minimum film formation temperature, but becomes a white powder in a temperature region equal to or lower than the minimum film formation temperature. The temperature at this boundary was measured as the minimum film formation temperature.

Measurement of Contact Angle The contact angle was measured at 25 ° C. using a contact angle measuring device. One drop of a polymer emulsion prepared so that the polymer fine particles become 10% by weight is dropped on a Teflon plate having a smooth surface,
The measurement was performed by reading the contact angle at that time with a microscope.

Measurement of Surface Tension A polymer emulsion prepared so that the amount of polymer fine particles was 35% by weight was used at 25 ° C. by using a fully automatic equilibrium electro surface tension digitiomatic ESB-IV type (manufactured by Kyowa Kagaku Co., Ltd.). The measurement was carried out.

The half-life of the reaction with the divalent metal ion
3 ml of a polymer emulsion prepared so that the measured polymer fine particles became 0.1% by weight was placed in a spectrophotometer cell so that air bubbles did not enter, and set in a sample chamber of the spectrophotometer. 1 mol / l magnesium chloride aqueous solution 1 in the cell
At the same time as dropping ml, the time change of the transmittance at a wavelength of 700 nm was measured. The time at which the transmittance for a predetermined time with respect to the initial transmittance became 50% was determined.

Preparation of Ink Composition The components as shown in Tables 3 and 4 below (in Tables 3 and 4, the units of the numerical values represent% by weight) were used to prepare the ink composition by performing the following operations. Prepared. First, a pigment, a dispersant, and water were mixed and dispersed in a sand mill (manufactured by Yaskawa Seisakusho) with glass beads (1.7 mm in diameter, 1.5 times the weight of the mixture) for 2 hours. Thereafter, the glass beads were removed to prepare an aqueous dispersion of the pigment. On the other hand, the polymer emulsion and other components were mixed and stirred at room temperature for 20 minutes to obtain a stirred product. The aqueous dispersion of the pigment was gradually added dropwise to the stirred product, and the mixture was further stirred for 20 minutes. This was filtered through a 5 μm membrane filter to obtain an ink composition.

Evaluation Test Evaluation Test of Polymer Emulsion 50 ml of the polymer emulsion prepared above was placed in a polypropylene container at room temperature (about 20 ° C.). afterwards,
After standing at 60 ° C. for 4 weeks, the polymer emulsion p
H and viscosity were determined. The evaluation was performed according to the following criteria. The results were as shown in Table 1 or Table 2 below. In Tables 1 and 2, MFT indicates the minimum film forming temperature of the polymer emulsion, and γ indicates the surface tension. Evaluation A: There was no change in pH and viscosity as compared with the initial values. Evaluation B: Compared with the initial value, the pH decreased by 10% and the viscosity increased by 10%. Evaluation C: Compared with the initial value, the pH decreased by 20% or more,
The viscosity increased by 20% or more.

Evaluation Test of Ink Composition The following ink evaluation test was performed on the above ink composition. The printing methods in Evaluations 2 and 3 were as follows. Inkjet printer MJ-700
C (manufactured by Seiko Epson Corporation), characters were printed on the following papers. Ink ejection amount is 0.07μ
g / dot and density were 360 dpi. The printing test paper used was as follows. Xerox P paper (Xerox Corporation) Xerox 4024 paper (Xerox Corporation) Xerox R paper (Xerox Corporation: recycled paper) Yamayuri Paper (Honshu Paper Co., Ltd .: recycled paper)

Evaluation 1: Storage stability 50 ml of the ink composition prepared above was placed in a polypropylene container at room temperature (about 20 ° C.). Then, after leaving at 60 ° C. for 4 weeks, the pH and viscosity of the polymer emulsion were examined. The evaluation was performed according to the following criteria. The results were as shown in Table 3 or Table 4 below. Evaluation A: There was no change in pH and viscosity as compared with the initial values. Evaluation B: Compared with the initial value, the pH decreased by 10% and the viscosity increased by 10%. Evaluation C: Compared with the initial value, the pH decreased by 20% or more,
The viscosity increased by 20% or more.

Evaluation 2: Clogging reliability The printer was filled with the ink composition, and alphanumeric characters were printed continuously for 10 minutes. Thereafter, the printer is stopped, and without capping, in an environment of a temperature of 40 ° C. and a humidity of 25%, 1
Left for a week. After the standing, alphanumeric characters were printed again, and the number of return operations required until a print quality equivalent to that before the standing was obtained was examined. The evaluation was performed according to the following criteria. The results were as shown in Table 3 or Table 4 below. Evaluation A: Print quality equivalent to the initial one was obtained by the return operation of 0 to 2 times. Evaluation B: Print quality equivalent to that of the initial stage was obtained by performing the return operation three to five times. Evaluation C: Print quality equivalent to the initial one could not be obtained after six or more return operations.

Evaluation 3: Ejection stability A printer was filled with the ink composition, alphanumeric characters were continuously printed, and dot missing and ink scattering were observed.
The number of sheets of recording paper on which dot missing and ink splattering occurred was examined and evaluated according to the following criteria. The results were as shown in Table 3 or Table 4 below. Evaluation A: Exceeded 5,000 sheets. Evaluation B: It was 1,000 or more and 5,000 or less. Evaluation C: Less than 1,000 sheets.

[0081]

[Table 1]

[0082]

[Table 2]

[0083]

[Table 3]

[0084]

[Table 4]

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Claims (18)

[Claims] 1. A method for producing a polymer emulsion comprising fine polymer particles, comprising: mixing at least water, a monomer, an emulsifier, and a polymerization initiator to carry out an emulsion polymerization reaction; To adjust the pH to the desired pH. 2. The method according to claim 1, wherein the water-soluble organic amine is a tertiary amino alcohol. (3) a tertiary amino alcohol represented by the following formula (I):
3. The method according to claim 2, wherein the method is one or a mixture of two or more represented by the formula (II). Embedded image [In the above formula (I), R represents the same or different one or two selected from the group consisting of an alkyl group, an aryl group, and a hydrogen atom, and m represents an integer of 1 to 3.] 2] [In the above formula (II), R represents the same or different one or two selected from the group consisting of an alkyl group, an aryl group, and a hydrogen atom, and m represents an integer of 1 to 3.] 4. The tertiary amino alcohol is triethanolamine, isopropanolamine, N, N-diethanolamine, N, N-dimethylethanolamine, N-
One or a mixture of two or more selected from the group consisting of (2-aminoethyl) ethanolamine, N-methyldiethanolamine, N, N-dibutylethanolamine, N-methylethanolamine, monoethanolamine, diethanolamine, and morpholine. Claim 2
The method described in. 5. The method of claim 1, wherein the desired pH is 7-9.
The method according to any one of the preceding claims. 6. The method according to claim 1, wherein the particle size of the polymer fine particles is 400 nm or less. 7. The method according to claim 1, wherein the glass transition point of the polymer fine particles is 30 ° C. or lower. 8. The method according to claim 1, wherein the polymer emulsion has a minimum film formation temperature of 30 ° C. or lower. 9. A polymer emulsion having a film-forming property, a carboxyl group on the surface thereof, and three volumes of a polymer emulsion having 0.1% by weight of the polymer fine particles;
When one volume of a 1 mol / l aqueous solution of a divalent metal salt is brought into contact, the transmittance of light having a wavelength of 700 nm becomes the initial value of 5%.
The method according to any one of claims 1 to 8, which has a reactivity with a divalent metal salt such that the time to become 0% is 1 × 10 ⁴ seconds or less. 10. The polymer emulsion prepared so as to contain 10% by weight of polymer fine particles has a contact angle of 70 ° or more on a Teflon (registered trademark) plate. The method according to one of the preceding claims. 11. A polymer emulsion adjusted to contain 35% by weight of polymer fine particles has a surface tension of 4%.
The method according to any one of claims 1 to 10, which is at least ^0x10-3 N / m (20C). 12. A polymer fine particle containing 1 to 10% by weight of a structure derived from an unsaturated vinyl monomer having a carboxyl group, and crosslinked by a crosslinking monomer having two or more polymerizable double bonds. The method according to any one of claims 1 to 11, which has a structure and contains 0.2 to 4% by weight of a structure derived from the crosslinkable monomer. 13. The method according to claim 1, wherein the polymer fine particles have a core-shell structure. 14. The method according to claim 13, wherein the core comprises a polymer having an epoxy group, and the shell comprises a polymer having a carboxyl group. 15. The method according to claim 1, wherein the polymer fine particles have self-crosslinking properties. 16. A polymer emulsion produced by the method according to any one of claims 1 to 15. 17. An ink composition comprising at least a coloring agent, a polymer emulsion, water and a water-soluble organic solvent, wherein the polymer emulsion is any one of claims 1 to 15. An ink composition produced by the method according to (1). 18. The content of the polymer fine particles constituting the polymer emulsion is 0.01 to 0.01 with respect to the ink composition.
The ink composition according to claim 17, which is 30% by weight.