JP2015124353A - Water-based ink for inkjet recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-based ink for inkjet recording excellent in adhesiveness to a resin-based recording medium such as PET and PP and glossiness.SOLUTION: There is provided a water-based ink for inkjet recording containing a coloring agent and polyester resin particles (A) A polyester resin constituting the polyester resin particles (A) contains a composite resin formed by covalent bound of a segment consisting of polyester resin (A1) and a segment consisting of addition polymerizing-based resin (A2), the segment (A2) contains a constitutional unit derived from at least one of acrylic acid ester having an alkyl group having 12 to 18 carbon atoms and methacrylic acid ester having an alkyl group having 12 to 18 carbon atoms (A2-1), in an amount of 5 mass% to 50 mass% in the segment (A2).

Description

  The present invention relates to an aqueous ink for inkjet recording, a method for producing the same, and an inkjet recording method.

The ink jet recording system is a recording system in which characters and images are obtained by ejecting ink droplets directly from a very fine nozzle and attaching them to a recording member. This method is widely spread because it is easy to make full color and is inexpensive, and has many advantages such as the ability to use plain paper as a recording member and non-contact with the object to be printed.
Also, because it is a water-based ink, PET (polyethylene terephthalate), PP (polypropylene), PVC (polyvinyl chloride), which has been conventionally printed with solvent-based inks, UV curable inks, etc. for reasons such as environmental impact and safety. The use of an ink jet recording method is also demanded for resin recording media such as).

Patent Document 1 discloses a polycondensable single ink as an emulsion ink for inkjet, which is excellent in ejection stability and adhesion to a recording material, and provides a fresh image with excellent storage stability (water resistance, weather resistance, etc.). An inkjet emulsion ink containing a resin particle containing a polycondensation resin obtained by polycondensation of at least one selected from the group consisting of a monomer, an oligomer thereof and a prepolymer, and a colorant, the resin particle and An ink-jet emulsion ink is disclosed wherein the colorant has a charge of the same polarity.
Patent Document 2 has flexibility unique to water-based polyurethane resins, good stability at high and low temperatures, and excellent plastics such as polyolefin (polyethylene, polypropylene, etc.), nylon, and polyester. Water-based polyurethane resin obtained by reacting, as a main component, an aliphatic hydrocarbon compound having one hydroxyl group and one carboxyl group, a high molecular weight polyol and a polyisocyanate compound, as the water-based polyurethane resin having excellent adhesion, and the water-based polyurethane A printing ink composition containing a printing ink binder using a resin is disclosed.
In Patent Document 3, a polyurethane resin and a fiber-based resin are essential components as a printing ink composition having excellent adhesion to substrates such as polypropylene, polyester, and nylon, and having excellent oil resistance, heat resistance, and blocking resistance. In this printing ink composition, the polyurethane resin is obtained by extending a chain of a urethane prepolymer obtained by reacting a polyol component and an organic diisocyanate with a diamine compound, and terminating at least one of a long-chain alkyl group and an alkenyl group. Disclosed is a printing ink composition characterized in that it is a polyurethane resin that has been quenched with an aliphatic amine compound having an alkyl group and / or an aliphatic amide compound having at least one of a long-chain alkyl group or an alkenyl group. Yes.

JP 2007-332286 A JP 2004-231813 A Japanese Patent Laid-Open No. 2004-204048

However, since resin-based recording media such as PET, PP, and PVC are non-water-absorbing media, water-based ink does not easily permeate, the fixability is low, and the ink spread on the film is poor. The ink film had poor smoothness and glossiness was insufficient.
An object of the present invention is to provide a water-based ink for inkjet recording that is excellent in adhesion and gloss to a resin recording medium such as PET and PP.

In order to solve the above-described problems with water-based inks, the present inventors have stabilized the components in the ink with high adhesion to the resin recording medium after printing the ink on the resin recording medium surface. It was considered that it was important to form a protective film. As a result, it contains composite resin particles having a segment made of a polyester resin and a segment made of an addition polymerization resin containing a specific amount of a structural unit derived from an acrylate ester or methacrylate ester having an alkyl group having a specific carbon number It has been found that adhesion and glossiness to resin recording media such as PET and PP can be improved.
That is, the present invention provides the following [1] to [3].
[1] A water-based ink for ink-jet recording containing a colorant and polyester resin particles (A), wherein the polyester resin constituting the polyester resin particles (A) is a segment (A1) comprising a polyester resin and an addition It contains a composite resin formed by covalently bonding a segment (A2) made of a polymerized resin, and the segment (A2) is an acrylate ester having an alkyl group having 12 to 18 carbon atoms and having 12 to 18 carbon atoms A water-based ink for ink-jet recording comprising 5% by mass or more and 50% by mass or less of a structural unit derived from at least one methacrylate ester having an alkyl group in the segment (A2).
[2] The method for producing a water-based ink for inkjet recording according to [1], comprising the following steps (1) to (3).
Step (1): A step of polymerizing raw material monomers of segment (A1) and segment (A2) to obtain a composite resin Step (2): mixing the composite resin obtained in step (1) with an aqueous medium, Step of obtaining an aqueous dispersion containing polyester resin particles (A) Step (3): An aqueous dispersion containing polyester resin particles (A) obtained in step (2) and an aqueous solution containing a colorant. Step 3 of mixing with a dispersion to obtain an aqueous ink for ink jet recording [3] After the aqueous ink for ink jet recording described in [1] is adhered to a resin recording medium by an ink jet recording method, the resin recording medium An ink jet recording method in which is heated to 70 ° C. or higher and 150 ° C. or lower.

  ADVANTAGE OF THE INVENTION According to this invention, the aqueous ink for inkjet recording which is excellent in the adhesiveness and glossiness to resin-made recording media, such as PET and PP, can be provided.

[1] First embodiment (water-based ink for inkjet recording)
The water-based ink for ink-jet recording according to the first embodiment of the present invention is a water-based ink for ink-jet recording containing a colorant and polyester-based resin particles (A), and is a polyester-based material constituting the polyester-based resin particles (A). The resin contains a composite resin in which a segment (A1) made of a polyester resin and a segment (A2) made of an addition polymerization resin are covalently bonded, and the segment (A2) is an alkyl group having 12 to 18 carbon atoms The structural unit (A2-1) derived from at least one of an acrylate ester having a carboxylic acid and a methacrylic acid ester having an alkyl group having 12 to 18 carbon atoms is contained in a segment (A2) in an amount of 5% by mass to 50% by mass. A water-based ink for ink-jet recording.
In the present specification, “water-based ink for ink-jet recording” may be simply referred to as “water-based ink”.

ADVANTAGE OF THE INVENTION According to this invention, the aqueous ink for inkjet recording which is excellent in the adhesiveness and glossiness to resin-made recording media, such as PET and PP, can be provided. The reason why the water-based ink for ink-jet recording of the present invention has such an effect is not clear, but is considered as follows.
Polyester has a hydroxyl group, a carboxy group, an ester group, etc. in the molecule. Therefore, water-based inks containing polyester have good adhesion to film media with polar groups, such as PET film, because they form hydrogen bonds, and also plasticize by affinity with highly polar water. As a result, the glass transition temperature of the surface is lowered, and thus a coating film having high smoothness is obtained after printing, so that the gloss is excellent. However, it has been difficult to obtain sufficient adhesion to low polarity film media such as PP film.

On the other hand, in the water-based ink of the present invention, the polyester resin constituting the polyester resin particles (A) is an acrylic ester or methacrylic acid having an alkyl group in addition to a segment (polyester segment) made of a polyester resin. It has a segment (vinyl polymer segment) made of an addition polymerization resin containing a specific amount of a structural unit derived from an ester. Since this alkyl group expresses a strong intermolecular force with the alkyl group of the film media, adhesion with a PP film having low polarity is improved. Here, since the resin containing an alkyl group is easily crystallized, the adhesion to the film and the smoothness of the surface are lowered. In the present invention, the carbon number and content of the alkyl group are controlled within an appropriate range. Thus, the adhesion can be improved while suppressing the expression of crystallinity. In addition, by using a vinyl polymer segment having an alkyl group as a resin combined with a polyester segment, a resin containing a long-chain alkyl group having a low affinity with water, utilizing the affinity of highly polar polyester with water. Since it can be stably dispersed in an aqueous medium, it can be contained in a water-based ink, and a water-based ink containing a polyester can be used for a film medium having a polar group such as a PET film. The excellent gloss obtained when applied can be obtained even in film media with low polarity such as PP.
As a result, the water-based ink of the present invention is considered to be excellent in both adhesion and gloss to film media having a low polarity such as PP in addition to film media having a high polarity such as PET. .
Hereinafter, each component and each process used for this invention are demonstrated.

[Polyester resin particles (A)]
The polyester resin constituting the polyester resin particles (A) is composed of a segment (A1) made of polyester resin (hereinafter also referred to as “polyester resin segment (A1)” or “segment (A1)”) and an addition polymerization resin. Segment (A2) (hereinafter also referred to as “addition polymerization resin segment (A2)” or “segment (A2)”) is contained, and the segment (A2) has 12 carbon atoms. In the segment (A2), 5 mass of the structural unit (A2-1) derived from at least one of an acrylate ester having an alkyl group of 18 or less and a methacrylate ester having an alkyl group of 12 to 18 carbon atoms. % To 50% by mass or less.

Here, the segment (A1) made of a polyester resin means that the segment (A1) is derived from the polyester resin. Further, the segment (A2) made of an addition polymerization resin means that the segment (A2) is derived from the addition polymerization resin. Furthermore, the composite resin may have other segments in addition to the segment (A1) and the segment (A2) as long as the effects of the present invention are not impaired. However, the total content of the segment (A1) and the segment (A2) in the composite resin is preferably 90% by mass or more, more preferably 95% by mass or more, and further preferably substantially 100% by mass. is there.
The resin constituting the polyester-based resin particles (A) may contain a resin other than the polyester-based resin as long as the effects of the present invention are not impaired, but the polyester in the polyester-based resin particles (A) The content of the system resin is preferably 90% by mass or more, more preferably 95% by mass or more, still more preferably 98% by mass or more, still more preferably substantially 100% by mass, and still more preferably 100% by mass. . As the resin other than the polyester-based resin, a known resin used for the water-based ink for inkjet recording, for example, a styrene-acrylic copolymer, epoxy, polycarbonate, polyurethane, or the like can be used.

<Polyester resin>
The polyester resin constituting the polyester resin particles (A) contains the composite resin.
The content of the composite resin is preferably 90 in the polyester resin constituting the polyester resin particles (A) from the viewpoint of obtaining a water-based ink having excellent adhesion to a resin recording medium such as PET and PP and glossiness. It is at least mass%, more preferably at least 95 mass%, still more preferably substantially 100 mass%, still more preferably 100 mass%.
Further, the content of the composite resin is preferably among all resins constituting the polyester resin particles (A) from the viewpoint of obtaining a water-based ink having excellent adhesion to a resin recording medium such as PET and PP and glossiness. Is 90% by mass or more, more preferably 95% by mass or more, still more preferably substantially 100% by mass, and still more preferably 100% by mass.

<Composite resin>
The segment (A2) is preferably 5% by mass or more, more preferably 10% by mass or more in the composite resin from the viewpoint of obtaining a water-based ink excellent in adhesion to a resin recording medium such as PET and PP and glossiness. More preferably, it is 15 mass% or more, More preferably, it is 18 mass% or more, Preferably it is 50 mass% or less, More preferably, it is 48 mass% or less, More preferably, it is 45 mass% or less, More preferably, it is 42 mass % Or less.
From the same viewpoint, the segment (A1) is preferably 50% by mass or more, more preferably 52% by mass or more, still more preferably 55% by mass or more, and still more preferably 58% by mass or more in the composite resin. Moreover, it is preferably 95% by mass or less, more preferably 90% by mass or less, still more preferably 85% by mass or less, and still more preferably 82% by mass or less.

The softening point of the composite resin is preferably 80 ° C. or higher, more preferably 90 ° C. or higher, and still more preferably 100 ° C. from the viewpoint of obtaining a water-based ink excellent in adhesion to a resin recording medium such as PET and PP and glossiness. Further, it is preferably 130 ° C. or lower, more preferably 125 ° C. or lower, and further preferably 120 ° C. or lower. In addition, a softening point can be measured by the method as described in an Example.
From the same viewpoint, the glass transition temperature of the composite resin is preferably 30 ° C. or higher, more preferably 40 ° C. or higher, still more preferably 45 ° C. or higher, still more preferably 50 ° C. or higher, and preferably 65 ° C. or lower. More preferably, it is 60 degrees C or less, More preferably, it is 55 degrees C or less. In addition, a glass transition temperature can be measured by the method as described in an Example.
The acid value of the composite resin is preferably 5 mgKOH / g or more, more preferably 8 mgKOH / g or more, and still more preferably, from the viewpoint of obtaining a water-based ink having excellent adhesion to a resin recording medium such as PET and PP and glossiness. It is 10 mgKOH / g or more, preferably 30 mgKOH / g or less, more preferably 25 mgKOH / g or less, still more preferably 23 mgKOH / g or less. In addition, an acid value can be measured by the method as described in an Example.

(Segment made of polyester resin (A1))
The polyester resin segment (A1) constituting the composite resin is a resin segment obtained by polycondensation of an alcohol component and a carboxylic acid component.

[Alcohol component]
The alcohol component which is a raw material monomer of the segment (A1) preferably contains an alkylene oxide adduct of bisphenol A from the viewpoint of obtaining a water-based ink having excellent adhesion to a resin recording medium such as PET and PP and glossiness. .
In the present invention, the alkylene oxide adduct of bisphenol A means the entire structure in which an oxyalkylene group is added to 2,2-bis (4-hydroxyphenyl) propane.
Specifically, the alkylene oxide adduct of bisphenol A is preferably a compound represented by the following general formula (I).

In the general formula (I), R ¹ O and R ² O are both oxyalkylene groups, preferably each independently an oxyalkylene group having 1 to 4 carbon atoms, more preferably an oxyethylene group or It is an oxypropylene group.
x and y correspond to the number of added moles of alkylene oxide. Furthermore, from the viewpoint of reactivity with the carboxylic acid component, the average value of the sum of x and y is preferably 2 or more, 7 or less, more preferably 2 or more and 5 or less, and even more preferably 2 or more and 3 or less.
Further, the x R ¹ O and the y R ² O may be the same or different, but the water-based ink is excellent in adhesion and glossiness to a resin recording medium such as PET and PP. From the viewpoint of obtaining The alkylene oxide adduct of bisphenol A may be used alone or in combination of two or more. The alkylene oxide adduct of bisphenol A is preferably a propylene oxide adduct of bisphenol A and an ethylene oxide adduct of bisphenol A, more preferably a propylene oxide adduct of bisphenol A, and more preferably combined use.
The content of the alkylene oxide adduct of bisphenol A in the alcohol component that is the raw material monomer of the segment (A1) is from the viewpoint of obtaining a water-based ink that is excellent in adhesion and glossiness to a resin recording medium such as PET and PP. Preferably they are 50 mol% or more and 100 mol% or less, More preferably, they are 70 mol% or more and 100 mol% or less, More preferably, they are 90 mol% or more and 100 mol% or less.

In addition to the alkylene oxide adduct of bisphenol A, the following alcohol components can be contained in the alcohol component which is a raw material monomer of the segment (A1).
Specifically, examples of the alcohol component of the raw material monomer derived from the structural unit of the segment (A1) (hereinafter also simply referred to as “raw material monomer of the segment (A1)”) include ethylene glycol, propylene glycol (1,2 -Propanediol), glycerin, pentaerythritol, trimethylolpropane, hydrogenated bisphenol A, sorbitol, or their alkylene (2 to 4 carbon atoms) oxide adduct (average number of added moles of 1 to 16). . You may use the said alcohol component individually or in combination of 2 or more types.

[Carboxylic acid component]
The segment (A1) is a polyester resin, and a carboxylic acid component is used in addition to the alcohol component as a raw material monomer.
Examples of the carboxylic acid component that is a raw material monomer of the segment (A1) include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid; sebacic acid, fumaric acid, maleic acid, adipic acid, succinic acid, alkyl groups, and Aliphatic dicarboxylic acids such as succinic acid and cyclohexanedicarboxylic acid having an alkenyl group; trivalent or higher polyvalent carboxylic acids such as trimellitic acid and pyromellitic acid, and anhydrides of these acids and their alkyl (carbons) (Equation 1 or more and 3 or less) esters.

  Among these, aromatic dicarboxylic acids and aliphatic dicarboxylic acids are used from the viewpoints of improving ink ejection properties and obtaining water-based inks having excellent adhesion and glossiness to resin recording media such as PET and PP. Preferably, at least one selected from the group consisting of isophthalic acid, terephthalic acid, fumaric acid and maleic acid is more preferable, and terephthalic acid and fumaric acid are still more preferable. The said carboxylic acid component may be individual or 2 or more types may be contained.

  In addition, as a carboxylic acid component, a carboxylic acid having a non-aromatic carbon-carbon unsaturated bond, for example, a carbon-carbon unsaturated bond portion of an unsaturated aliphatic carboxylic acid and / or an unsaturated alicyclic carboxylic acid is In the composite resin, it can be a binding portion with the segment (A2).

Examples of carboxylic acids having non-aromatic carbon-carbon unsaturated bonds (unsaturated aliphatic carboxylic acids and unsaturated alicyclic carboxylic acids) include unsaturated fats such as fumaric acid, maleic acid, acrylic acid, and methacrylic acid. Group carboxylic acids; unsaturated alicyclic carboxylic acids such as tetrahydrophthalic acid. From the viewpoint of obtaining a water-based ink excellent in adhesion to a resin recording medium such as PET and PP and glossiness, an unsaturated aliphatic carboxylic acid is preferable, and acrylic acid and methacrylic acid are more preferable.
In the present embodiment, a carboxylic acid having a non-aromatic carbon-carbon unsaturated bond may be referred to as “a bireactive monomer”.

  In the carboxylic acid component, the content of the both reactive monomers is preferably 1 mol% or more, more preferably 3 from the viewpoint of obtaining a water-based ink excellent in adhesion to a resin recording medium such as PET and PP and glossiness. It is at least 5 mol%, more preferably at least 5 mol%, preferably at most 20 mol%, more preferably at most 15 mol%, still more preferably at most 10 mol%.

  From the viewpoint of appropriately adjusting the particle diameter of the resin particles in the segment (A1) and obtaining a water-based ink having excellent adhesion and glossiness to a resin recording medium such as PET and PP, the hydroxyl group of the alcohol component and the carboxylic acid component The molar ratio (hydroxyl group / carboxy group) to carboxy group is preferably 100/80 to 100/120, more preferably 100/85 to 100/110, still more preferably 100/90 to 100/105. .

(Segment made of addition polymerization resin (A2))
The segment (A2) constituting the composite resin is a segment made of an addition polymerization resin composed of a structural unit derived from the addition polymerizable monomer (a2) (hereinafter also referred to as “monomer (a2)”).
This segment (A2) contains at least one of an acrylate ester having an alkyl group having 12 to 18 carbon atoms and a methacrylate ester having an alkyl group having 12 to 18 carbon atoms (hereinafter referred to as “addition polymerizable monomer (a2)”. -1) ”may be contained in the segment (A2) in an amount of 5% by mass to 50% by mass.
If this structural unit (A2-1) is 5 mass% or more in a segment (A2), adhesiveness with film media with low polarity like PP film will improve. Moreover, if it is 50 mass% or less, since adhesiveness with highly polar film media like PET film will improve and a coating film with high smoothness will be obtained, it is excellent in glossiness. From this viewpoint, the structural unit (A2-1) is preferably 8% by mass or more, more preferably 10% by mass or more, still more preferably 15% by mass or more, and preferably 45% in the segment (A2). It is at most 42 mass%, more preferably at most 42 mass%.

  In the addition polymerizable monomer (a2-1), the alkyl group preferably has 14 to 18 carbon atoms, more preferably 16 to 18 carbon atoms, and still more preferably 18 carbon atoms, from this viewpoint. is there. Moreover, it is preferable that a C12-C18 alkyl group is linear from a viewpoint of improving adhesiveness with film media with low polarity like PP film.

  It is preferable that the segment (A2) which comprises composite resin contains the structural unit (A2-2) derived from a styrene-type compound (a2-2) other than the said structural unit (A2-1). The content of the structural unit (A2-2) is preferably 50% by mass or more in the segment (A2) from the viewpoint of obtaining a water-based ink having excellent adhesion to a resin recording medium such as PET and PP and gloss. More preferably 55% by mass or more, still more preferably 58% by mass or more, and preferably 95% by mass or less, more preferably 92% by mass or less, still more preferably 90% by mass or less, and still more preferably 85% by mass. % Or less.

Examples of the styrene compound (a2-2) include styrene such as styrene, methylstyrene, α-methylstyrene, β-methylstyrene, t-butylstyrene, chlorostyrene, chloromethylstyrene, methoxystyrene, styrenesulfonic acid or a salt thereof. Are preferred, more preferably contain styrene, and even more preferably styrene.
The composite resin may contain a structural unit derived from another monomer in addition to the structural unit (A2-1) and the structural unit (A2-2).
Other monomers include (meth) acrylic acid other than (a2-1), such as alkyl (meth) acrylate (having 1 to 22 carbon atoms), benzyl (meth) acrylate, and dimethylaminoethyl (meth) acrylate. Esters; Olefins such as ethylene, propylene and butadiene; Halovinyls such as vinyl chloride; Vinyl esters such as vinyl acetate and vinyl propionate; Vinyl ethers such as vinyl methyl ether; Vinylidene halides such as vinylidene chloride; N-vinyl 1 type, or 2 or more types, such as N-vinyl compounds, such as pyrrolidone, are mentioned.

Specific examples of the (meth) acrylic acid ester include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, (iso) propyl (meth) acrylate, (iso or tertiary) butyl (meth) acrylate, (iso) Examples include amyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (iso) octyl (meth) acrylate, (iso) decyl (meth) acrylate, and the like.
In addition, “(iso or tertiary)” and “(iso)” mean both cases in which these groups are present and cases in which these groups are not present. “(Meth) acrylate” refers to acrylate or methacrylate.

<Manufacture of composite resin>
There is no restriction | limiting in particular in the manufacturing method of composite resin, A composite resin can be obtained by superposing | polymerizing the raw material monomer of segment (A1) and segment (A2), Any of the following 1st-3rd manufacturing methods It is preferable to manufacture by.
From the viewpoint of controlling the reactivity of the monomer, a catalyst such as an esterification catalyst or an esterification co-catalyst may be used, and a polymerization initiator and a polymerization inhibitor may be further used.

(1) 1st manufacturing method The 1st manufacturing method prepares polyester resin (a1) (henceforth "resin (a1)") by polycondensation of an alcohol component and a carboxylic acid component (polycondensation). Step), followed by addition polymerization (addition polymerization step) of the addition polymerizable monomer (a2) in the presence of the polyester resin (a1).

(Polycondensation process)
In the polycondensation step, an alcohol component and a carboxylic acid component are polycondensed to prepare a polyester resin (a1).
This polyester resin (a1) is a polyester resin obtained by polycondensation of an alcohol component and a carboxylic acid component, and is preferable for constituting the segment (A1) made of the polyester resin. Moreover, the suitable kind and suitable content of the alcohol component and carboxylic acid component of resin (a1) are the same as the case of the said segment (A1).

For example, the polyester resin (a1) is obtained by polycondensing the alcohol component and the carboxylic acid component at a temperature of 180 ° C. or higher and 250 ° C. or lower using an esterification catalyst as necessary in an inert gas atmosphere. Can be manufactured.
The polyester resin preferably has a sharp molecular weight distribution from the viewpoint of controlling the particle size of the resin particles and obtaining a water-based ink excellent in adhesion and gloss to a resin recording medium such as PET, PP, and esterification. It is preferable to perform polycondensation using a catalyst. Examples of the esterification catalyst include metal compounds such as tin catalyst, titanium catalyst, antimony trioxide, zinc acetate, and germanium dioxide. From the viewpoint of the reaction efficiency of the esterification reaction in the synthesis of the polyester resin, a tin catalyst is preferable. As the tin catalyst, dibutyltin oxide, di (2-ethylhexane) acid tin, salts thereof and the like are preferably used, and di (2-ethylhexane) acid tin is more preferably used. Although there is no restriction | limiting in the usage-amount of an esterification catalyst, Preferably it is 0.01 mass part or more with respect to 100 mass parts of total amounts of an acid component and an alcohol component, More preferably, it is 0.1 mass part or more, Preferably it is 1 mass part or less, More preferably, it is 0.8 mass part or less.

Further, an esterification cocatalyst such as gallic acid may be used. The amount of the esterification cocatalyst used is preferably 0.001 part by mass or more, more preferably 0.01 part by mass or more, and preferably 0 with respect to 100 parts by mass of the total amount of the acid component and the alcohol component. 0.5 parts by mass or less, more preferably 0.1 parts by mass or less.
Moreover, a radical polymerization inhibitor can be used as needed. Examples of the radical polymerization inhibitor include tert-butylcatechol. The amount of the radical polymerization inhibitor used is preferably 0.001 part by mass or more, more preferably 0.005 part by mass or more, and preferably 0 with respect to 100 parts by mass of the total amount of the acid component and the alcohol component. 0.5 parts by mass or less, more preferably 0.1 parts by mass or less.

  In the polycondensation step, all of the carboxylic acid components that are raw materials of the segment (A1) may be used, but it is preferable to use a part in the polycondensation step and the rest in the addition polymerization step. When a carboxylic acid having a non-aromatic carbon-carbon unsaturated bond is used as the bireactive monomer, it is preferably used in the addition polymerization step. Thereby, the composite resin formed by covalently bonding the segment (A1) and the segment (A2) can be manufactured satisfactorily. In the case where a divalent or higher polyvalent carboxylic acid having a non-aromatic carbon-carbon unsaturated bond is not used as the bireactive monomer, the non-aromatic carbon-carbon unsaturation is performed after the addition polymerization step. It is preferable to add a radical polymerization inhibitor such as a divalent or higher polyvalent carboxylic acid having a bond and 4-t-butylcatechol. Thereby, the composite resin which has the segment (A1) containing the bivalent or more polyvalent carboxylic acid component which has a non-aromatic carbon-carbon unsaturated bond can be manufactured favorably.

(Addition polymerization process)
In the addition polymerization step, the addition polymerizable monomer (a2) is subjected to addition polymerization in the presence of the polyester resin (a1). The details of the addition polymerizable monomer (a2) are as described above.
In the addition polymerization step, it is preferable to add the carboxylic acid component not used in the polycondensation step to the polyester resin (a1) together with the addition polymerizable monomer (a2). Thereby, the composite resin formed by covalently bonding the segment (A1) and the segment (A2) can be manufactured satisfactorily.
In the addition polymerization step, it is preferable to use a radical polymerization initiator. As the radical polymerization initiator, known ones can be used, for example, peroxides such as dibutyl peroxide and dicumyl peroxide, azo compounds such as 2,2′-azobis (2,4-dimethylvaleronitrile), etc. Is mentioned. The amount of the radical polymerization initiator used varies depending on the type of the polymerization initiator and the like, but is preferably 0.1 parts by mass or more, more preferably 0.5 parts per 100 parts by mass of the total amount of the addition polymerizable monomer (a2). It is at least 10 parts by mass, preferably at most 10 parts by mass, more preferably at most 5 parts by mass.
The reaction temperature in the addition polymerization step varies depending on the kind of the polymerization initiator and the like, but is preferably 120 ° C. or higher, more preferably 140 ° C. or higher, still more preferably 150 ° C. or higher, and preferably 215 ° C. or lower, more preferably Is 210 ° C. or lower, more preferably 205 ° C. or lower.

(2) Second production method The second production method involves an addition polymerization reaction (addition polymerization step) with the raw material monomer (addition polymerizable monomer (a2)) of the addition polymerization resin segment (A2). This is a method of performing a polycondensation reaction (polycondensation step) using a raw material monomer of the polyester resin segment (A1).
The alcohol component and the carboxylic acid component are allowed to exist in the reaction system during the addition polymerization reaction, and polycondensation is performed by adding an esterification catalyst and, if necessary, an esterification co-catalyst at a temperature suitable for the polycondensation reaction. The reaction can be started, or the polycondensation reaction can be started by adding it later to the reaction system under temperature conditions suitable for the polycondensation reaction. In the former case, the molecular weight and molecular weight distribution can be adjusted by adding an esterification catalyst and, if necessary, an esterification co-catalyst at a temperature suitable for the polycondensation reaction.

(3) Third production method The third production method comprises a polycondensation reaction using an alcohol component and a carboxylic acid component and an addition polymerization reaction using a raw material monomer (addition polymerizable monomer (a2)) of an addition polymerization resin segment (A2). It is a method of performing in parallel.
In this method, it is preferable to perform the polycondensation reaction and the addition polymerization reaction under the reaction temperature conditions suitable for the addition polymerization reaction, raise the reaction temperature, and perform the reaction under the temperature conditions suitable for the polycondensation reaction. At that time, under a temperature condition suitable for the polycondensation reaction, a radical polymerization inhibitor can be added to advance only the polycondensation reaction.

<Polyester resins other than composite resins>
Polyester resins other than the composite resin can be produced by polycondensation of an alcohol component and a carboxylic acid component, similarly to the polyester resin segment (A1). Specific examples of the preferred acid component and alcohol component are preferably the same as those of the polyester resin used in the polyester resin segment (A1).
The softening point, glass transition temperature, and acid value of polyester resins other than the composite resin are preferably in the same range as the composite resin.

<Method for producing polyester resin particles (A)>
The polyester resin particles (A) are preferably produced by a method in which the polyester resin containing the composite resin described above is dispersed in an aqueous medium to obtain an aqueous dispersion of the polyester resin particles (A).
The aqueous medium preferably contains water as a main component. From the viewpoint of improving the dispersion stability of the resin particle dispersion and from the viewpoint of environmental safety, the water content in the aqueous medium is preferably 80 masses. % Or more, more preferably 90% by mass or more, still more preferably substantially 100% by mass. As water, deionized water or distilled water is preferably used. Examples of components other than water include organic solvents that dissolve in water, such as alcohol solvents such as methanol, ethanol, isopropanol, and butanol; ketone solvents such as acetone and methyl ethyl ketone; and ether solvents such as tetrahydrofuran.

  As a method of dispersing a polyester resin in an aqueous medium, a method of adding a polyester resin containing a composite resin to an aqueous medium and performing a dispersion treatment with a disperser or the like, or an aqueous medium in a polyester resin containing a composite resin The method by phase inversion emulsification is preferable from the viewpoint of obtaining a water-based ink excellent in adhesion to a resin recording medium such as PET and PP and glossiness. As the phase inversion emulsification method, it is preferable to first dissolve a polyester-based resin containing a composite resin in an organic solvent, then add an aqueous medium to the solution to perform phase inversion, and then remove the organic solvent. Hereinafter, the phase inversion emulsification method will be described.

[Phase inversion emulsification method]
First, a polyester resin containing a composite resin is dissolved in an organic solvent to obtain a solution.
When multiple types of composite resins or resins other than composite resins are included, a mixture of these composite resins and other resins may be used in advance, but these resins are simultaneously added to an organic solvent and dissolved. A solution may be obtained.
Moreover, the viewpoint which improves the affinity to the aqueous medium of the polyester-type resin containing a composite resin, improves the dispersion stability of a resin particle dispersion liquid, and the adhesiveness and glossiness to resin-made recording media, such as PET and PP. From the viewpoint of obtaining a water-based ink having excellent properties, it is preferable to use a basic aqueous solution.
As a method for obtaining a solution, a method in which a polyester resin containing a composite resin and an organic solvent are placed in a container and dissolved, then a basic aqueous solution is placed in the container and stirred with a stirrer to obtain a solution is preferable.
The dissolving operation of the polyester resin in the organic solvent and the subsequent addition of the basic aqueous solution are usually performed at a temperature not higher than the boiling point of the organic solvent.

The organic solvent is preferably a dialkyl ketone having an alkyl group having 1 to 3 carbon atoms such as acetone and methyl ethyl ketone from the viewpoint of dissolving a polyester-based resin containing a composite resin and easy removal from an emulsion. More preferred is methyl ethyl ketone.
The mass ratio of the organic solvent to the polyester resin (organic solvent / polyester resin) is preferably from the viewpoint of dissolving the resin and facilitating phase inversion to an aqueous medium, and improving the dispersion stability of the resin particles. 0.3 or more, more preferably 0.5 or more, still more preferably 0.7 or more, preferably 5 or less, more preferably 3 or less, still more preferably 2 or less, still more preferably 1.5 or less. It is.

Examples of the basic compound used in the basic aqueous solution include inorganic basic compounds and organic basic compounds.
Examples of the inorganic base compound include hydroxides, carbonates and hydrogen carbonates of alkali metals such as potassium, sodium and lithium. Specific examples thereof include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and hydrogen carbonate. Examples include sodium and potassium bicarbonate. Examples of the organic base include ammonia and alkanolamines such as diethylethanolamine. From the viewpoint of improving the dispersion stability of the resin particle dispersion, and from the viewpoint of obtaining a water-based ink having excellent adhesion and glossiness to a resin recording medium such as PET and PP, sodium hydroxide, potassium hydroxide, sodium carbonate, Potassium carbonate is preferred, and sodium hydroxide is more preferred.

The concentration of the basic compound in the basic aqueous solution is preferably 1% by mass or more, more preferably 3% by mass or more, preferably from the viewpoint of improving the dispersion stability and productivity of the resin particle dispersion. It is 60 mass% or less, More preferably, it is 50 mass% or less.
Next, an aqueous medium is added to the resin mixture, and phase inversion is performed to obtain an aqueous dispersion containing a polyester resin.
From the viewpoint of improving the dispersion stability of the resin particle dispersion, the temperature at the time of adding the aqueous medium is preferably 10 ° C. or higher, more preferably 20 ° C. or higher, further preferably 25 ° C. or higher, and preferably 80 ° C. or lower, more preferably 75 ° C. or lower.
The addition speed of the aqueous medium is such that the phase inversion is completed from the viewpoint of improving the dispersion stability of the resin particle dispersion and from the viewpoint of obtaining a water-based ink having excellent adhesion and glossiness to a resin recording medium such as PET and PP. Is preferably 0.5 parts by mass / min or more, more preferably 1 part by mass / min or more, still more preferably 3 parts by mass / min or more, still more preferably 100 parts by mass of the resin constituting the resin particles. Is 5 parts by weight or more, preferably 100 parts by weight or less, more preferably 50 parts by weight or less, still more preferably 20 parts by weight or less, and even more preferably 15 parts by weight / minute. It is as follows. There is no restriction | limiting in the addition speed | rate of the aqueous medium after the resin phase is obtained after phase inversion.

The addition amount of the aqueous medium is preferably 50 parts by mass or more, more preferably 100 parts by mass or more, and still more preferably from 100 parts by mass of the resin constituting the resin particles, from the viewpoint of improving the productivity of the aqueous dispersion. It is 150 parts by mass or more, preferably 900 parts by mass or less, more preferably 500 parts by mass or less, and still more preferably 400 parts by mass or less.
After phase inversion emulsification, the organic solvent may be removed from the dispersion obtained by phase inversion emulsification, if necessary.
The method for removing the organic solvent is not particularly limited, and any method can be used. However, since it is dissolved in water, it is preferably distilled.

The aqueous dispersion containing the polyester resin particles (A) thus obtained is preferably filtered through a wire mesh or the like to remove coarse particles and the like. In addition, when the organic solvent is removed, water is azeotropically reduced with the organic solvent, so it is preferable to adjust the solid concentration by adding water.
The solid content concentration after adjustment is preferably 5% by mass or more, more preferably 10% by mass or more, and still more preferably from the viewpoint of obtaining a water-based ink excellent in adhesion to a resin recording medium such as PET and PP and glossiness. Is 20% by mass or more, more preferably 25% by mass or more, preferably 50% by mass or less, more preferably 45% by mass or less, still more preferably 40% by mass or less, and still more preferably 35% by mass or less. It is.

The pH of the aqueous dispersion containing the obtained polyester resin particles (A) is preferably 6 or more from the viewpoint of obtaining a water-based ink having excellent adhesion and glossiness to a resin recording medium such as PET and PP. More preferably, it is 6.5 or more, preferably 8 or less, more preferably 7.5 or less, and still more preferably 7.2 or less.
The volume average particle diameter of the polyester resin particles (A) is preferably 50 nm or more from the viewpoint of obtaining a water-based ink excellent in ejection properties and excellent in adhesion and glossiness to resin recording media such as PET and PP. More preferably, it is 100 nm or more, More preferably, it is 130 nm or more, Preferably it is 300 nm or less, More preferably, it is 250 nm or less, More preferably, it is 200 nm or less.
The volume average particle diameter of the polyester resin particles (A) is measured by a dynamic light scattering method, and specifically, measured by the method of the example.

[Colorant]
In the present invention, the colorant means a pigment or a dye. Further, as described later, the colorant may be made into fine particles that are stable in the ink using a surfactant or a polymer. The colorant used in the present invention is not particularly limited, and pigments, hydrophobic dyes, water-soluble dyes (acidic dyes, reactive dyes, direct dyes, etc.) can be used, but the water resistance and dispersion stability of the ink can be used. From the viewpoint of improving scratch resistance, pigments and hydrophobic dyes are preferred. Among them, it is preferable to use a pigment in order to express the high weather resistance which has been recently demanded.

<Pigment>
The pigment may be either an inorganic pigment or an organic pigment. If necessary, they can be used in combination with extender pigments.
Examples of the inorganic pigment include carbon black and metal oxide, and carbon black is particularly preferable for black ink.
Examples of organic pigments include azo pigments, diazo pigments, phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, dioxazine pigments, perylene pigments, perinone pigments, thioindigo pigments, anthraquinone pigments, and quinophthalone pigments.
The hue is not particularly limited, and any chromatic pigment such as yellow, magenta, cyan, blue, red, orange, and green can be used.

Specific examples of preferred organic pigments include C.I. I. Pigment yellow, C.I. I. Pigment Red, C.I. I. Pigment orange, C.I. I. Pigment violet, C.I. I. Pigment blue, and C.I. I. One or more types of products selected from the group consisting of pigment green are listed.
Among these, quinacridone pigments are preferable from the viewpoint of improving the color developability of the ink.
Moreover, solid solution pigments, such as a quinacridone solid solution pigment, can also be used suitably. The quinacridone solid solution pigment includes β-type and γ-type unsubstituted quinacridone and 2,9-dimethylquinacridone (CI Pigment Red 122), or β-type and γ-type unsubstituted quinacridone and 2,9- It consists of dichloroquinacridone such as dichloroquinacridone, 3,10-dichloroquinacridone, and 4,11-dichloroquinacridone. The quinacridone solid solution pigment is preferably a solid solution pigment composed of a combination of unsubstituted quinacridone (CI Pigment Violet 19) and 2,9-dichloroquinacridone (CI Pigment Red 202).

In the present invention, a self-dispersing pigment can also be used. Self-dispersing pigments are those in which one or more hydrophilic functional groups (anionic hydrophilic groups such as carboxy groups and sulfonic acid groups, or cationic hydrophilic groups such as quaternary ammonium groups) are directly or other atomic groups. It means an inorganic pigment or an organic pigment that can be dispersed in an aqueous medium without using a surfactant or a resin. Here, as other atomic groups, an alkanediyl group having 1 to 12 carbon atoms, a phenylene group, a naphthylene group, or the like can be given.
Examples of commercially available self-dispersing pigments include Cab-O-Jet 260M (a derivative of 2,9-dimethylquinacridone (CI Pigment Red 122)), 200, 300, 400, 270Y manufactured by Cabot Corporation. 470Y, 740Y, 554B, 480V, 352B, 260M, 265M, 465M, 250C, 450C, 1027R; BONJET BLACK CW-1, CW-2, M-800 manufactured by Orient Chemical Co., Ltd .; Aqua- manufactured by Tokai Carbon Co., Ltd. Black 001, 162 and the like.
The above pigments can be used alone or in admixture of two or more at any ratio.

<Colorants other than pigments>
The hydrophobic dye is not particularly limited as long as it can be contained in the polymer particles. From the viewpoint of efficiently incorporating the dye in the polymer, the hydrophobic dye is 2 g / L or more, preferably 20 g / L or more and 500 g / L or less (25%) with respect to the organic solvent (preferably methyl ethyl ketone) used in the production of the polymer. C.) It is desirable to dissolve. Here, the hydrophobic dye means a dye having a solubility of preferably less than 6% by mass in 100 g of water (20 ° C.).
Examples of the hydrophobic dye include oil-soluble dyes and disperse dyes. Among these, oil-soluble dyes are preferable.
Examples of the oil-soluble dye include C.I. I. Solvent Black, C.I. I. Solvent Yellow, C.I. I. Solvent Red, C.I. I. Solvent Violet, C.I. I. Solvent Blue, C.I. I. Solvent Green, and C.I. I. One or more types of products selected from the group consisting of solvent orange are listed, and are commercially available from Orient Chemical Industries, BASF, and the like.
The above colorants can be used alone or in admixture of two or more at any ratio.

<Polymer particles containing colorant>
When the colorant is used in water-based ink, it is preferable to use a surfactant and a polymer to form fine particles that are stable in the ink. In particular, from the viewpoint of improving the ink bleeding resistance and water resistance, it is more preferable to include a colorant in the polymer particles, and it is further preferable to include a pigment and / or a hydrophobic dye in the polymer particles. Preferably, it is even more preferable to include a pigment and / or a hydrophobic dye in the water-insoluble polymer particles.
Below, the polymer particle containing a coloring agent is demonstrated.

From the viewpoint of improving the image density of the ink, the volume average particle diameter of the polymer particles containing the colorant is preferably 40 nm or more, more preferably 50 nm or more, and preferably 200 nm or less, more preferably 150 nm or less. is there.
The volume average particle diameter of the polymer particles containing the colorant is measured by a dynamic light scattering method, and specifically measured by the method of the example.

(Water-insoluble polymer)
For the polymer particles containing the colorant, it is preferable to use a water-insoluble polymer from the viewpoint of improving the water dispersibility of the polymer particles in the ink and the image density of the ink. Here, the “water-insoluble polymer” of the present invention is a polymer that is dried at 105 ° C. for 2 hours, and when the polymer that has reached a constant weight is dissolved in 100 g of water at 25 ° C., the dissolved amount is 10 g or less. The dissolution amount is preferably 5 g or less, more preferably 1 g or less. In the case of an anionic polymer, the dissolution amount is the dissolution amount when the anionic group of the polymer is neutralized 100% with sodium hydroxide.
Examples of the polymer used include polyesters, polyurethanes, and vinyl polymers. From the viewpoint of improving the storage stability of the ink, it can be obtained by addition polymerization of vinyl monomers (vinyl compounds, vinylidene compounds, vinylene compounds). Vinyl polymers are preferred.

  As the vinyl polymer, a monomer mixture (hereinafter, referred to as “(a) component”) and (b) a hydrophobic monomer (hereinafter also referred to as “(b) component”) (hereinafter referred to as “vinyl monomer”). A vinyl-based polymer obtained by copolymerizing (also simply referred to as “monomer mixture”) is preferable. This vinyl polymer has a structural unit derived from the component (a) and a structural unit derived from the component (b). Especially, what contains the structural unit derived from (c) macromer (henceforth "(c) component") is preferable.

[(A) ionic monomer]
The (a) ionic monomer is preferably used as a monomer component of the water-insoluble polymer from the viewpoint of stably dispersing the polymer particles containing the colorant in the ink. Examples of the ionic monomer include an anionic monomer and a cationic monomer, and an anionic monomer is preferable.
Examples of the anionic monomer include a carboxylic acid monomer, a sulfonic acid monomer, and a phosphoric acid monomer.
Examples of the carboxylic acid monomer include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, and 2-methacryloyloxymethyl succinic acid.
Among the anionic monomers, carboxylic acid monomers are preferable, and acrylic acid and methacrylic acid are more preferable from the viewpoint of improving dispersion stability of the polymer particles containing the colorant in the ink.

[(B) Hydrophobic monomer]
The (b) hydrophobic monomer is preferably used as a monomer component of the water-insoluble polymer from the viewpoint of improving the dispersion stability of the polymer particles containing the colorant in the ink. Examples of the hydrophobic monomer include alkyl (meth) acrylates and aromatic group-containing monomers.
As the alkyl (meth) acrylate, those having an alkyl group having 1 to 22 carbon atoms, preferably 6 to 18 carbon atoms are preferable. For example, methyl (meth) acrylate, ethyl (meth) acrylate, (iso) propyl (Meth) acrylate, (iso or tertiary) butyl (meth) acrylate, (iso) amyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (iso) octyl (meth) acrylate, ( Examples include iso) decyl (meth) acrylate, (iso) dodecyl (meth) acrylate, (iso) stearyl (meth) acrylate, and the like.
In addition, “(iso or tertiary)” and “(iso)” mean both cases in which these groups are present and cases in which these groups are not present. “(Meth) acrylate” refers to acrylate or methacrylate.

As the aromatic group-containing monomer, a vinyl monomer having an aromatic group having 6 to 22 carbon atoms, which may have a substituent containing a hetero atom, is preferable, and a styrenic monomer, an aromatic group-containing (meth) Acrylate is more preferred.
As the styrenic monomer, styrene, 2-methylstyrene, and divinylbenzene are preferable, and styrene is more preferable.
Moreover, as an aromatic group containing (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, etc. are preferable, and benzyl (meth) acrylate is more preferable.
(B) As for the hydrophobic monomer, two or more kinds of the above-mentioned monomers can be used, but a styrene monomer and an aromatic group-containing (meth) acrylate can be used in combination, and benzyl (meth) acrylate and styrene are used in combination. However, it is more preferable to use benzyl (meth) acrylate alone.

[(C) Macromer]
(C) The macromer is a compound having a polymerizable functional group at one end, preferably a compound having a number average molecular weight of 500 or more and 100,000 or less, and a viewpoint of improving the dispersion stability of the polymer particles containing the colorant in the ink. Therefore, it is preferably used as a monomer component of a water-insoluble polymer. The polymerizable functional group present at one end is preferably an acryloyloxy group or a methacryloyloxy group, and more preferably a methacryloyloxy group.
(C) The number average molecular weight of the macromer is more preferably 1,000 or more and 10,000 or less. The number average molecular weight is measured by gel permeation chromatography, and is measured using chloroform or the like as a solvent and polystyrene or the like as a standard substance.
(C) As the macromer, from the viewpoint of improving dispersion stability of the polymer particles containing the colorant in the ink, an aromatic group-containing monomer-based macromer and a silicone-based macromer are preferable, and the aromatic group-containing monomer-based macromer is preferably used. More preferred.
Examples of the aromatic group-containing monomer constituting the aromatic group-containing monomer-based macromer include the aromatic group-containing monomers described in the above (b) hydrophobic monomer, styrene and benzyl (meth) acrylate are preferable, and styrene is more preferable. preferable.
Specific examples of the styrenic macromer include AS-6 (S), AN-6 (S), HS-6 (S) (trade name of Toagosei Co., Ltd.) and the like.
Examples of the silicone macromer include organopolysiloxane having a polymerizable functional group at one end.

[(D) Nonionic monomer]
In the water-insoluble polymer, from the viewpoint of improving the dispersion stability of the polymer particles containing the colorant in the ink, (d) a nonionic monomer (hereinafter also referred to as “(d) component”) is used as a monomer component. It is preferable to use it.
(D) As a component, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, polypropylene glycol (n = 2-30, n shows the average addition mole number of an oxyalkylene group. The same hereafter). Polyalkylene glycol (meth) acrylates such as (meth) acrylate and polyethylene glycol (n = 2 to 30) (meth) acrylate; alkoxypolyalkylene glycols such as methoxypolyethylene glycol (n = 1 to 30) (meth) acrylate (meta ) Acrylate; phenoxy (ethylene glycol / propylene glycol copolymer) (n = 1 to 30, ethylene glycol: n = 1 to 29 therein) (meth) acrylate and the like. Among these, alkoxy polyalkylene glycol (meth) acrylate is preferable, and methoxypolyethylene glycol (n = 1 to 30) (meth) acrylate is more preferable.

Specific examples of the commercially available component (d) include NK Esters M-20G, 40G, 90G, and 230G from Shin-Nakamura Chemical Co., Ltd., Bremer PE-90 from NOF Corporation, 200, 350, PME-100, 200, 400, PP-500, 800, etc., AP-150, 400, 550, 50PEP-300, 50POEP-800B, 43PAPE-600B, etc. .
The components (a) to (d) can be used alone or in admixture of two or more.

Components (a) to (d) in the monomer mixture of the above-mentioned components (a) to (d) at the time of vinyl polymer production (contents as unneutralized amounts; the same applies hereinafter) or water-insoluble polymers The content of the structural unit derived from is as follows.
The content of the component (a) is preferably 2% by mass or more, more preferably 5% by mass or more, and particularly preferably 8% by mass from the viewpoint of improving dispersion stability of the polymer particles containing the colorant in the ink. % Or more, preferably 40% by mass or less, more preferably 30% by mass or less, and particularly preferably 25% by mass or less.
The content of the component (b) is preferably 5% by mass or more, more preferably 10% by mass or more, preferably from the viewpoint of improving dispersion stability of the polymer particles containing the colorant in the ink. Is 98% by mass or less, more preferably 90% by mass or less, and still more preferably 80% by mass or less.

When the component (c) is contained, the content of the component (c) is preferably 1% by mass or more, more preferably 5 from the viewpoint of improving dispersion stability of the polymer particles containing the colorant in the ink. It is at least mass%, preferably at most 25 mass%, more preferably at most 20 mass%.
In the case of containing the component (d), the content of the component (d) is preferably 5% by mass or more, more preferably 10 from the viewpoint of improving dispersion stability of the polymer particles containing the colorant in the ink. It is at least mass%, preferably at most 50 mass%, more preferably at most 40 mass%.
Further, the mass ratio of [(a) component / [(b) component + (c) component]] when the component (c) is contained is determined by the dispersion stability of the polymer particles containing the colorant in the ink and From the viewpoint of improving the image density of the ink, it is preferably 0.01 or higher, more preferably 0.02 or higher, still more preferably 0.03 or higher, still more preferably 0.05 or higher, still more preferably 0.10 or higher. Moreover, it is preferably 1 or less, more preferably 0.67 or less, and still more preferably 0.50 or less.

(Production of water-insoluble polymer)
The water-insoluble polymer is produced by copolymerizing a monomer mixture by a known polymerization method. As the polymerization method, a solution polymerization method is preferable.
Although there is no restriction | limiting in the solvent used by the solution polymerization method, Polar organic solvents, such as C1-C3 aliphatic alcohol, ketones, ethers, and esters, are preferable, and specifically, methanol, ethanol, acetone, methyl ethyl ketone And methyl ethyl ketone is preferred.
In the polymerization, a polymerization initiator or a polymerization chain transfer agent can be used. As the polymerization initiator, an azo compound is preferable, and 2,2′-azobis (2,4-dimethylvaleronitrile) is more preferable. . As the polymerization chain transfer agent, mercaptans are preferable, and 2-mercaptoethanol is more preferable.

Although preferable polymerization conditions vary depending on the type of polymerization initiator and the like, the polymerization temperature is preferably 50 ° C. or higher and 80 ° C. or lower, and the polymerization time is preferably 1 hour or longer and 20 hours or shorter. The polymerization atmosphere is preferably a nitrogen gas atmosphere or an inert gas atmosphere such as argon.
After completion of the polymerization reaction, the produced polymer can be isolated from the reaction solution by a known method such as reprecipitation or solvent distillation. In addition, unreacted monomers and the like can be removed from the obtained polymer by reprecipitation, membrane separation, chromatographic methods, extraction methods and the like.
The weight average molecular weight of the water-insoluble polymer used in the present invention is preferably 5,000 from the viewpoint of improving the dispersion stability of the polymer particles containing the colorant in the ink and the image density of the ink. Or more, more preferably 10,000 or more, still more preferably 20,000 or more, preferably 500,000 or less, more preferably 400,000 or less, still more preferably 300,000 or less, and still more preferably 200. , 000 or less. In addition, the measurement of a weight average molecular weight can be performed by the method as described in an Example.

<Production of polymer particles containing colorant>
The polymer particles containing the colorant are preferably produced by a method having the following steps A and B as an aqueous dispersion.
Step A: A step of dispersing a mixture containing a water-insoluble polymer, an organic solvent, a colorant, and water to obtain a dispersion of polymer particles containing a colorant Step B: From the dispersion obtained in Step A The process of removing the said organic solvent and obtaining the aqueous dispersion of the polymer particle containing a coloring agent Although it is an arbitrary process, you may perform the process C further.
Step C: A step of mixing the aqueous dispersion obtained in Step B and a cross-linking agent to cross-link water-insoluble polymer particles containing a colorant.

(Process A)
In step A, first, a water-insoluble polymer is dissolved in an organic solvent to obtain an organic solvent solution of the water-insoluble polymer, and then a colorant, water, and a neutralizing agent, a surfactant, and the like are obtained. A method of adding an organic solvent solution and mixing to obtain an oil-in-water dispersion is preferred. Although there is no restriction | limiting in the order added to the organic solvent solution of a water-insoluble polymer, It is preferable to add in order of water, a neutralizing agent, and a coloring agent.
Although there is no restriction | limiting in the organic solvent in which a water-insoluble polymer is dissolved, C1-C3 aliphatic alcohol, ketones, ethers, esters, etc. are preferable, ketones are more preferable, and methyl ethyl ketone is still more preferable. When a water-insoluble polymer is synthesized by a solution polymerization method, the solvent used in the polymerization may be used as it is.

When the water-insoluble polymer is an anionic polymer, an anionic group in the water-insoluble polymer may be neutralized using a neutralizing agent. When using a neutralizing agent, it is preferable to neutralize so that pH may be 7 or more and 11 or less. Examples of the neutralizing agent include bases such as lithium hydroxide, sodium hydroxide, potassium hydroxide, ammonia, and various amines. Further, the water-insoluble polymer may be neutralized in advance.
The degree of neutralization of the anionic group of the water-insoluble polymer is preferably at least 10 mol%, more preferably 20 mol, from the viewpoint of improving the dispersion stability of the polymer particles containing the colorant in the ink and in the aqueous medium. % Or more, more preferably 30 mol% or more, and preferably 300 mol% or less, more preferably 200 mol% or less, still more preferably 150 mol% or less.
Here, the degree of neutralization is obtained by dividing the molar equivalent of the neutralizing agent by the molar amount of the anionic group of the water-insoluble polymer.

In the dispersion, the colorant is preferably 5% by mass or more, more preferably 10% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less. Further, the organic solvent is preferably 10% by mass or more, preferably 70% by mass or less, more preferably 50% by mass or less.
In the dispersion, the water-insoluble polymer is preferably 2% by mass or more, more preferably 3% by mass or more, and preferably 40% by mass or less, more preferably 20% by mass or less. Water is preferably 10% by mass or more, more preferably 20% by mass or more, and preferably 70% by mass or less.
The mass ratio of the amount of the colorant to the amount of the water-insoluble polymer [colorant / water-insoluble polymer] is 50 from the viewpoint of improving the dispersion stability of the polymer particles containing the colorant in the ink and in the aqueous medium. / 50 to 90/10 is preferable, 60/40 to 80/20 is more preferable, and 70/30 to 80/20 is still more preferable.

There is no particular limitation on the dispersion method of the dispersion in step A. The volume average particle diameter of the polymer particles containing the colorant can be atomized only by the main dispersion until the desired particle diameter is obtained. Preferably, after pre-dispersing, the main dispersion is further performed by applying a shear stress. The volume average particle size of the polymer particles containing the colorant is preferably controlled to a desired particle size. The temperature in the dispersion in step A is preferably 0 ° C. or higher and 40 ° C. or lower, more preferably 0 ° C. or higher and 25 ° C. or lower, and the dispersion time is preferably 1 hour or longer, more preferably 2 hours or longer, and preferably It is 30 hours or less, more preferably 25 hours or less.
When the dispersion is predispersed, a commonly used mixing and stirring device such as an anchor blade or a disper blade, particularly a high-speed stirring and mixing device is preferable.

  Examples of means for applying the shear stress of the present dispersion include a kneader such as a roll mill and a kneader, a high-pressure homogenizer such as a microfluidizer (trade name, manufactured by Microfluidics), a media-type disperser such as a paint shaker and a bead mill. . Examples of commercially available media dispersers include Ultra Apex Mill (trade name, manufactured by Kotobuki Industries Co., Ltd.), Pico Mill (trade name, manufactured by Asada Tekko Co., Ltd.), and the like. A plurality of these devices can be combined. Among these, it is preferable to use a high-pressure homogenizer from the viewpoint of reducing the particle size of the polymer particles containing the colorant.

(Process B)
In Step B, an aqueous dispersion of polymer particles containing a colorant can be obtained by removing the organic solvent from the dispersion obtained in Step A by a known method. The organic solvent in the aqueous dispersion containing the polymer particles containing the obtained colorant is preferably substantially removed, but may remain as long as the object of the present invention is not impaired. The amount of the residual organic solvent is preferably 0.1% by mass or less, and more preferably 0.01% by mass or less.
If necessary, the dispersion can be heated and stirred before the organic solvent is distilled off.
The obtained aqueous dispersion of polymer particles containing a colorant is obtained by dispersing solid polymer particles containing a colorant in a medium containing water as a main medium. Here, the form of the polymer particles is not particularly limited as long as the particles are formed of at least a colorant and a water-insoluble polymer. For example, a particle form in which a colorant is included in the water-insoluble polymer, a particle form in which the colorant is uniformly dispersed in the water-insoluble polymer, a particle form in which the colorant is exposed on the surface of the water-insoluble polymer particle, and the like. Included, and mixtures thereof.

(Process C)
Step C is an optional step, but is a step in which the aqueous dispersion obtained in Step B and a crosslinking agent are mixed and subjected to crosslinking treatment to polymer particles containing a colorant. Step C is preferably performed from the viewpoint of the storage stability of the aqueous dispersion and the ink.
Here, when the water-insoluble polymer is an anionic water-insoluble polymer having an anionic group, the crosslinking agent is preferably a compound having a functional group that reacts with the anionic group. , Preferably 2 to 6 are more preferable.
Preferred examples of the crosslinking agent include compounds having two or more epoxy groups in the molecule, compounds having two or more oxazoline groups in the molecule, and compounds having two or more isocyanate groups in the molecule. Then, a compound having two or more epoxy groups in the molecule is preferable, and trimethylolpropane polyglycidyl ether is more preferable.

The amount of the crosslinking agent used is preferably 0.3 / 100 to 50/100 in terms of the mass ratio of [crosslinking agent / anionic water-insoluble polymer] from the viewpoint of improving the storage stability of the aqueous dispersion and the ink. 100-40 / 100 is more preferable, and 5 / 100-25 / 100 is still more preferable.
The obtained aqueous dispersion of water-insoluble polymer particles containing a colorant is preferably filtered through a wire mesh to remove coarse particles and the like. In addition, from the viewpoint of improving the productivity and storage stability of the aqueous dispersion, various additives such as organic solvents, preservatives, and antifungal agents, which are arbitrarily added to the aqueous ink described later, include a colorant. It may be added to an aqueous dispersion of water-insoluble polymer particles.
The solid content concentration of the aqueous dispersion of the water-insoluble polymer particles containing the colorant is improved in the productivity and storage stability of the aqueous dispersion, and the adhesion and gloss to the resin recording medium such as PET and PP. From the viewpoint of obtaining a water-based ink having excellent properties, it is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 15% by mass or more, and preferably 50% by mass or less, more preferably 45% by mass. Hereinafter, it is more preferably 40% by mass or less, and still more preferably 35% by mass or less.

[Water-based ink for inkjet recording]
The water-based ink for inkjet recording of the present invention contains the aforementioned colorant and polyester resin particles (A).
The content of the colorant contained in the water-based ink of the present invention is preferably 1% by mass in the water-based ink from the viewpoint of obtaining a water-based ink excellent in adhesion to a resin recording medium such as PET and PP and gloss. More preferably, it is 2% by mass or more, more preferably 3% by mass or more, preferably 25% by mass or less, more preferably 10% by mass or less, and further preferably 5% by mass or less.
The content of the polyester-based resin particles (A) contained in the water-based ink of the present invention is from the viewpoint of improving the discharge property of the water-based ink and the adhesion and glossiness to a resin recording medium such as PET and PP. From the viewpoint of obtaining an excellent aqueous ink, it is preferably 1% by mass or more, more preferably 2% by mass or more, still more preferably 3% by mass or more, and preferably 15% by mass or less, more preferably, in the aqueous ink. It is 10 mass% or less, More preferably, it is 7 mass% or less.

The content of water contained in the aqueous ink of the present invention is preferably 25% by mass or more, more preferably 30% by mass or more, and still more preferably 35% in the aqueous ink from the viewpoint of improving the dischargeability of the aqueous ink. % By mass or more, more preferably 40% by mass or more, preferably 90% by mass or less, more preferably 80% by mass or less, still more preferably 70% by mass or less, still more preferably 60% by mass or less, and more. More preferably, it is 55 mass% or less, More preferably, it is 50 mass% or less, More preferably, it is 45 mass% or less.
The mass ratio of the colorant to the polyester resin particles (A) contained in the water-based ink of the present invention [colorant / polyester resin particles (A)] is used to improve the discharge property of the water-based ink, as well as PET and PP. From the viewpoint of obtaining a water-based ink that is excellent in adhesion to a resin recording medium such as a water-based ink, it is preferably 20/80 to 70/30, more preferably 30/70 to 60/40, and still more preferably water-based ink. Is 40/60 to 50/50, more preferably 40/60 to 48/52.

[Optional components of water-based ink]
The water-based ink of the present invention can contain various additives such as organic solvents, penetrants, dispersants, surfactants, viscosity modifiers, antifoaming agents, antiseptics, antifungal agents, and rust inhibitors.
Examples of the organic solvent include dialkyl ketones having an alkyl group having 1 to 3 carbon atoms, polyhydric alcohols such as glycerin, 1,2-hexanediol, diethylene glycol, ethylene glycol, and acetylene glycol, and 2-pyrrolidone. Of pyrrolidone, triethylene glycol monobutyl ether, polyoxyethylene lauryl ether and the like are preferred, and it is more preferred to use two or more of these together.
In the present invention, the content of the organic solvent is preferably 5% by mass or more, more preferably 8% by mass or more, and still more preferably 10% by mass or more in the aqueous ink from the viewpoint of improving the dischargeability of the aqueous ink. Moreover, it is preferably 30% by mass or less, more preferably 27% by mass or less, and still more preferably 20% by mass or less.

In the present invention, the content of the surfactant is preferably 0.1% by mass or more, more preferably 0.5% by mass or more in the aqueous ink, from the viewpoint of improving the dischargeability of the aqueous ink. Moreover, Preferably it is 5 mass% or less, More preferably, it is 2 mass% or less.
The above-described water-based ink for ink-jet recording of the present invention is excellent in ejectability, fixability to a resin-made recording medium, and image storability at high temperatures. According to the ink jet recording method of the present invention described below, it is possible to further improve the discharge property, the fixing property to the resin recording medium, and the image storability at a high temperature.

[2] Second embodiment (Method for producing water-based ink for inkjet recording)
The water-based ink for ink-jet recording of the present invention can be suitably produced by going through the following steps (1) to (3).
Step (1): A step of polymerizing raw material monomers of segment (A1) and segment (A2) to obtain a composite resin Step (2): mixing the composite resin obtained in step (1) with an aqueous medium, Step of obtaining an aqueous dispersion containing polyester resin particles (A) Step (3): An aqueous dispersion containing polyester resin particles (A) obtained in step (2) and an aqueous solution containing a colorant. Step of mixing with a dispersion to obtain a water-based ink for inkjet recording

[Step (1) and Step (2)]
Step (1) and step (2) are as described above.

[Step (3)]
In step (3), the aqueous dispersion containing the polyester resin particles (A) obtained in step (2), the aqueous dispersion containing a colorant, and the optional components described above are mixed as necessary. To do. Next, the suitable example of a process (3) is demonstrated.
First, water such as ion-exchanged water and, if necessary, an optional organic solvent and at least one of various additives are mixed and stirred as necessary to obtain a mixed solution.
Next, this mixed liquid is mixed with an aqueous dispersion containing a colorant, and further stirred and mixed while dropping the aqueous dispersion of the polyester resin particles (A) obtained in the step (2). Accordingly, the water-based ink can be suitably obtained by filtering with a filter or the like.

[3] Third embodiment (inkjet recording method)
In the ink jet recording method of the present invention, a water-based ink containing a colorant and polyester resin particles (A) is attached to a resin recording medium by an ink jet recording method, and then the resin recording medium is 70 ° C. or higher and 150 ° C. or lower. This is an ink jet recording method in which heating is performed.
The details of the water-based ink are the same as described above, and will be omitted.

In the ink jet recording method of the present invention, since a resin recording medium is used as the recording medium, the fixing property to the recording medium and the image storability at high temperature, which are the effects of the water-based ink of the present invention, can be further exhibited.
Further, in the present invention, after the water-based ink is adhered to the resin recording medium, the resin recording medium is heated to 70 ° C. or higher and 150 ° C. or lower, so that the fixing property to the recording medium and the image storability at high temperature are further improved. It can be demonstrated.

  Hereinafter, the present invention will be described more specifically with reference to examples and the like. In the following examples and the like, each physical property was measured by the following method. “Parts” and “%” are “parts by mass” and “% by mass” unless otherwise specified.

[Acid Values of Composite Resins A to K, Polyester Resin L, Resin Blend M, and Addition Polymer Resin N]
The measurement solvent was measured according to JIS K0070, except that the mixed solvent of ethanol and ether was changed to a mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

[Softening points of composite resins A to K, polyester resin L, resin blend M, and addition polymerization resin N]
Using a flow tester “CFT-500D” (manufactured by Shimadzu Corporation), a 1 g sample was heated at a heating rate of 6 ° C./min, and a load of 1.96 MPa was applied by a plunger, and the diameter was 1 mm and the length was 1 mm. Extruded from the nozzle. The amount of plunger drop of the flow tester was plotted against the temperature, and the temperature at which half of the sample flowed out was taken as the softening point.

[Glass transition temperatures of composite resins A to K, polyester resin L, resin blend M, and addition polymerization resin N]
Using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan), 0.01 to 0.02 g of a sample was weighed into an aluminum pan, heated to 200 ° C., and the temperature Then, the sample was cooled to 0 ° C. at a temperature lowering rate of 10 ° C./min to prepare a measurement sample. Then, the temperature is increased at a rate of temperature increase of 10 ° C / min, and the glass transition takes place at the intersection of the base line extension below the endothermic peak temperature and the tangent that indicates the maximum slope from the peak rise to the peak apex. It was temperature.

[Volume Average Particle Size (D _V ) of Resin Particles in Aqueous Dispersion of Polyester Resin Particles]
The volume average particle diameter (D _V ) was measured under the following conditions using a dynamic light scattering particle size measuring instrument “ZETASIZER NANO ZS” (manufactured by Malvern).
Solid content concentration: 0.1% by mass
Measurement temperature: 25 ° C
Medium: Water Measurement cell: Glass Cuvette
Laser specification: He-Ne, 4mW, 633nm
Detection optical system: NIBS, 173 ° C.
Number of measurements: 10 times Isothermal time: 5 minutes Analysis software: Zeta Sizer Software 6.2
Analysis method: General Purpose Mode (cumulant method)

[Solid content concentration of aqueous dispersion of polyester resin particles]
Using an infrared moisture meter “FD-230” (manufactured by Ketto Scientific Laboratory Co., Ltd.), 5 g of an aqueous dispersion was subjected to a drying temperature of 150 ° C. and a measurement mode 96 (monitoring time 2.5 minutes / variation width 0.05%). The water dispersion (mass%) of the aqueous dispersion was measured. The solid content concentration was calculated according to the following formula.
Solid content concentration (% by mass) = 100-M
M: moisture (mass%) of the aqueous dispersion = [(W−W ₀ ) / W] × 100
W: Sample mass before drying (initial sample mass)
W ₀ : Sample weight after drying (absolute dry weight)

[PH of aqueous dispersion of polyester resin particles]
It measured at 25 degreeC using pH meter "HM-20P" (made by Toa DKK Corporation).

[Measurement of weight average molecular weight of water-insoluble polymer (anionic polymer)]
Using a solution obtained by dissolving phosphoric acid and lithium bromide in N, N-dimethylformamide so as to have a concentration of 60 mmol / L and 50 mmol / L, respectively, the gel permeation chromatography method [GPC apparatus manufactured by Tosoh Corporation (HLC- 8120GPC), Tosoh Corporation column (TSK-GEL, α-M × 2), flow rate: 1 mL / min]. Polystyrene “A-500”, “A-2500”, “F-1”, and “F-10” (all of which are manufactured by Tosoh Corporation) were used as standard substances. The sample was dissolved in N, N-dimethylformamide to give a solution having a solid content of 0.3% by mass.

[Measurement of solid content concentration of aqueous dispersion of pigment-containing water-insoluble polymer particles (pigment-containing anionic polymer particles)]
Weigh out 10.0 g of sodium sulfate constant in a desiccator into a 30 mL ointment container, add approximately 1.0 g of the sample to it, mix, then weigh accurately and maintain at 105 ° C. for 2 hours. The volatile matter was removed, and the sample was left in a desiccator for 15 minutes, and the mass was measured. The mass of the sample after removal of the volatile matter was taken as the solid content and divided by the mass of the added sample to obtain the solid content concentration.

[Measurement of Volume Average Particle Size (D _V ) of Water-Insoluble Polymer Particles Containing Pigment (Pigment-Containing Anionic Polymer Particles)]
Measurement was performed using a laser particle analysis system “ELS-8000” (manufactured by Otsuka Electronics Co., Ltd., cumulant analysis). A dispersion diluted with water so that the concentration of particles to be measured was about 5 × 10 ⁻³ mass% was used. The measurement conditions were a temperature of 25 ° C., an angle between incident light and a detector of 90 °, and the number of integrations of 100. The refractive index of water (1.333) was input as the refractive index of the dispersion solvent.

[Evaluation of adhesion]
1.0 g of water-based ink was applied to a PET film “Lumirror 75T60” (manufactured by Toray Industries, Inc.) and a corona-treated PP film “FOR-15” (manufactured by Futamura Chemical Co., Ltd.), a table coater “ModelTC-1” (manufactured by Mitsui Denki Co., Ltd.) . After coating with 20 wire bars, drying for 10 minutes with a dryer at 80 ° C., and standing for one day in an environmental room at 25 ° C. and 50%, a tape “Cello Tape CT15” with a length of 4 cm on the coated surface (Registered trademark, manufactured by Nichiban Co., Ltd.) was applied, and then peeled off at an angle of 90 ° at a speed of 10 cm / sec, and the degree of peeling was visually evaluated in the following 11 stages.
(Evaluation criteria)
Peeling area 0%: 10-point peeling area 5% or less: 9-point peeling area 10% or less: 8-point peeling area 20% or less: 7-point peeling area 30% or less: 6-point peeling area 40% or less: 5-point peeling area 50 % Or less: 4-point peel area 60% or less: 3-point peel area 70% or less: 2-point peel area 80% or less: 1-point peel area 100% or less: 0 points

[Glossiness evaluation]
1.0 g of water-based ink was applied to a PET film “Lumirror 75T60” (manufactured by Toray Industries, Inc.) with a desktop coater “Model TC-1” (manufactured by Mitsui Denki Co., Ltd.) NO. After coating with 20 wire bars, it is dried for 10 minutes with a dryer at 80 ° C., and the coated surface is placed on KP cut paper (made by Kokusai Pulp & Paper Co., Ltd.). ”(Manufactured by Horiba Ltd.) at an incident angle of 60 °. The greater the value, the better the gloss.

Production Examples 1-11
(Manufacture of composite resins A to K)
The raw material monomer of the segment A1 (polyester resin) other than fumaric acid and both reactive monomers shown in Tables 1 and 2, esterification catalyst and esterification co-catalyst, thermometer, stainless steel stirring rod, flow-down condenser and nitrogen introduction tube Was put in a 5 liter four-necked flask equipped with the above, and the temperature was raised to 235 ° C. over 2 hours in a mantle heater in a nitrogen atmosphere. After confirming that the reaction rate reached 95% or higher at 235 ° C., the reaction rate was cooled to 160 ° C., and the raw material monomer of segment A2 (addition polymerization resin) shown in Tables 1 and 2 and both reactive monomers and radical polymerization A mixed solution of the initiator was added dropwise over 1 hour. Then, after maintaining at 160 ° C. for 30 minutes, the temperature was raised to 200 ° C., further reacted for 1 hour under a reduced pressure of 8 kPa, and then cooled to 180 ° C. Fumaric acid and a radical polymerization inhibitor were added, and the temperature was raised to 210 ° C. over 2 hours. After reacting at 210 ° C. for 1 hour, the reaction was carried out at 40 kPa until reaching the softening points shown in Tables 1 and 2 to obtain composite resins A to K. The reaction rate means a value of the amount of generated reaction water (mol) / theoretical amount of generated water (mol) × 100.
Tables 1 and 2 show the physical properties and the like of the obtained composite resins A to K.

Production Example 12
(Manufacture of polyester resin L)
The raw material monomer of the polyester resin other than fumaric acid shown in Table 2, the esterification catalyst and the esterification cocatalyst were placed in a 5-liter four-necked flask equipped with a thermometer, a stainless stir bar, a flow-down condenser and a nitrogen inlet tube. And heated up to 235 ° C. in a mantle heater over 2 hours in a nitrogen atmosphere. Thereafter, it was confirmed that the reaction rate reached 95% or higher at 235 ° C., cooled to 180 ° C., fumaric acid and a radical polymerization inhibitor were added, and the temperature was raised to 210 ° C. over 2 hours. After reacting at 210 ° C. for 1 hour, the reaction was carried out at 40 kPa until the softening point reached 120 ° C. to obtain a polyester resin L.
Table 2 shows the physical properties and the like of the obtained polyester resin L.

Production Example 13
(Production of resin blend M)
The raw material monomer of the polyester resin other than fumaric acid shown in Table 2, the esterification catalyst and the esterification cocatalyst were placed in a 5-liter four-necked flask equipped with a thermometer, a stainless stir bar, a flow-down condenser and a nitrogen inlet tube. And heated up to 235 ° C. in a mantle heater over 2 hours in a nitrogen atmosphere. Thereafter, it was confirmed that the reaction rate reached 95% or higher at 235 ° C., cooled to 160 ° C., and a mixed solution of the raw material monomer of the addition polymerization resin and the radical polymerization initiator shown in Table 2 was dropped over 1 hour. did. Then, after maintaining at 160 ° C. for 30 minutes, the temperature was raised to 200 ° C., further reacted for 1 hour under a reduced pressure of 8 kPa, and then cooled to 180 ° C. Fumaric acid and a radical polymerization inhibitor were added, and the temperature was raised to 210 ° C. over 2 hours. After reacting at 210 ° C. for 1 hour, the reaction was carried out at 40 kPa until the softening point shown in Table 2 was reached, thereby obtaining a resin blend M which was a mixture of a polyester resin and an addition polymerization resin.
Table 2 shows the physical properties and the like of the obtained resin blend M.

Production Example 14
(Production of addition polymerization resin N)
179 g of styrene as an addition polymerization monomer, 45 g of stearyl methacrylate, and 224 g of methyl ethyl ketone as a polymerization solvent are placed in a 2 liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser, and a nitrogen introduction tube, and 70 in an oil bath. After raising the temperature to 0 ° C., 9 g of perbutyl PV (t-Butyl peroxypivalate, 10-hour half-life temperature 54.6 ° C. (manufactured by NOF Corporation)) is added as a polymerization initiator, and the polymerization reaction is performed while stirring at 70 ° C. for 10 hours in a nitrogen atmosphere. The addition polymerization resin N was obtained.
Table 2 shows the physical properties and the like of the obtained addition polymerization resin N.

Production Examples 15 to 26
(Manufacture of a to l such as an aqueous dispersion containing polyester resin particles)
Into a four-necked flask equipped with a nitrogen inlet tube, a reflux condenser, a stirrer (“Three-One Motor BL300” (manufactured by Shinto Kagaku Co., Ltd.)) and a thermocouple, a composite resin of the types and blending amounts shown in Table 3 is placed. The mixture was mixed with 200 g of methyl ethyl ketone at 30 ° C. and dissolved. Next, after adding 5% aqueous sodium hydroxide in the amount shown in Table 3 and stirring for 30 minutes, deionized water was added dropwise at 30 ° C. with stirring at a rate of 20 mL / min, and then the temperature was raised to 60 ° C. The methyl ethyl ketone was distilled off while gradually reducing the pressure from 80 kPa to 30 kPa. After cooling to 25 ° C., the mixture was filtered through a 150-mesh wire mesh, the solid content concentration was adjusted to 30% by mass with ion-exchanged water, and an aqueous dispersion containing polyester resin particles was obtained.
Table 3 shows the physical properties and the like of the obtained aqueous dispersion.

Production Example 27 (Comparative Example 6)
Into a four-necked flask equipped with a nitrogen introduction tube, a reflux condenser, a stirrer (“Three-One Motor BL300” (manufactured by Shinto Kagaku Co., Ltd.)) and a thermocouple, the resin blend M having the blending amount shown in Table 3 was placed. At 200C, 200 g of methyl ethyl ketone was mixed and dissolved. Next, after adding 5% aqueous sodium hydroxide in the amount shown in Table 3 and stirring for 30 minutes, deionized water was added dropwise at 30 ° C. with stirring at a rate of 20 mL / min. A dispersion could not be obtained.

Production Example 28 (Comparative Example 7)
Methyl ethyl ketone of addition polymerization resin N having the compounding amount shown in Table 3 in a four-necked flask equipped with a nitrogen introduction tube, a reflux condenser, a stirrer (“Three-One Motor BL300” (manufactured by Shinto Kagaku)) and a thermocouple. 400 g of a solution (solid content: 50% by mass) was added, and then 5% aqueous sodium hydroxide solution in the amount shown in Table 3 was added and stirred for 30 minutes, followed by deionized water at 30 ° C. with stirring at a rate of 20 mL / min. Was added dropwise, and gelation occurred during the dropping, and an aqueous dispersion was not obtained.

Production Example 29 (Preparation of aqueous dispersion of water-insoluble polymer particles containing colorant (pigment))
(1) Synthesis of water-insoluble polymer (anionic polymer) 399 parts of benzyl methacrylate (manufactured by Wako Pure Chemical Industries, Ltd.), 91 parts of methacrylic acid (manufactured by Wako Pure Chemical Industries, Ltd.), methoxypolyethylene glycol methacrylate “M-230G” (new) Nakamura Chemical Co., Ltd., average addition mole number of oxyethylene group 23) 140 parts, styrene macromer “AS-6S” (manufactured by Toagosei Co., Ltd., solid content 50%) 140 parts are mixed, and monomer mixture (770 parts) Was prepared. In a reaction vessel, 15.75 parts of methyl ethyl ketone, 0.350 part of a polymerization chain transfer agent (2-mercaptoethanol) and 10% (77 parts) of the monomer mixture were mixed and subjected to nitrogen gas replacement.
Meanwhile, 80% (616 parts) of the monomer mixture, 2.45 parts of the polymerization chain transfer agent, 173.25 parts of methyl ethyl ketone, and polymerization initiator “V-65” (manufactured by Wako Pure Chemical Industries, Ltd., 2 , 2'-azobis (2,4-dimethylvaleronitrile)) 5.6 parts was added, and the mixture was heated to 75 ° C. while stirring the mixed solution in the reaction vessel in a nitrogen atmosphere. Was added dropwise over 4.5 hours. Thereafter, a mixture of the remaining 10% (77 parts) of the monomer mixture, 0.7 part of the polymerization chain transfer agent, 126 parts of methyl ethyl ketone and 1.4 parts of the polymerization initiator was added at 75 ° C. as a second drop. It was added dropwise over 7 hours.
After completion of dropping, 2.1 parts of the initiator were mixed, heated to 80 ° C., and stirred for 1.5 hours. By mixing the initiator, raising the temperature and stirring the mixture two more times, a polymer solution (polymer weight average molecular weight: 26000) was obtained.

(2) Production of aqueous dispersion of pigment-containing water-insoluble polymer particles (pigment-containing anionic polymer particles) 20 parts of the polymer obtained by drying the polymer solution obtained in (1) under reduced pressure was added to methyl ethyl ketone 62. Dissolve in 8 parts, add 5.01 part of 5N aqueous sodium hydroxide, 1.13 parts of 25% aqueous ammonia, and 236.5 parts of ion-exchanged water, and use a disper blade at 10-15 ° C. The mixture was stirred and mixed at 2000 rpm for 15 minutes. Subsequently, 45 parts of magenta pigment: PV19 “Inkjet Magenta E5B02” (manufactured by Clariant) and 25 parts of PR122 “6111T” (manufactured by Dainichi Seika Kogyo Co., Ltd.) are added, and 3 hours at 7000 rpm using a disperse blade at 10-15 ° C. Stir and mix. The obtained dispersion was filtered through 200 mesh and subjected to a 20-pass dispersion treatment at a pressure of 150 MPa using a microfluidizer “M-110K” (manufactured by Microfluidics, high-pressure homogenizer).
Methyl ethyl ketone was removed from the obtained dispersion at 60 ° C. under reduced pressure, a part of water was further removed, the mixture was centrifuged, and the liquid layer portion was filtered through a filter having a pore size of 5 μm (manufactured by Sartorius Stedim Biotech) to obtain a coarse particle. Particles were removed. Further, 80 parts of this dispersion was mixed with 5.0 parts of glycerin (manufactured by Kao Corporation), 0.2 part of proxel XL2 (manufactured by Avicia) and 14.8 parts of ion-exchanged water, and sterilized at 70 ° C. for 1 hour. After cooling to 25 ° C. and filtering with a filter having a pore size of 5 μm, an aqueous dispersion of pigment-containing water-insoluble polymer particles (pigment-containing anionic polymer particles) (solid content concentration 20% by mass, Volume average particle size 133 nm] was obtained.

Examples 1-7 and Comparative Examples 1-7
(Manufacture of water-based ink)
In a 100 mL screw tube, 8.67 parts of glycerin (manufactured by Kao Corporation), 15.0 parts of diethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.), “Surfinol 104PG50” (manufactured by Nissin Chemical Industry Co., Ltd., active ingredients: acetylene glycol, wetting agent ) 1.50 parts, 1.50 parts of “Emulgen 120” (manufactured by Kao Corporation, polyoxyethylene lauryl ether, emulsifier) and 29.96 parts of ion-exchanged water are mixed with a magnetic stirrer at room temperature for 15 minutes. A mixed solution was obtained.
Next, 26.67 parts of the aqueous dispersion of pigment-containing anionic polymer particles obtained in Production Example 29 (4.0 parts in terms of pigment content (in 100 parts of aqueous ink)) was stirred with a magnetic stirrer, while The mixed solution is mixed and further stirred and mixed while dropping 16.7 parts (5.0 parts in terms of solid content (in 100 parts of water-based ink)) of an aqueous dispersion containing the polyester resin particles shown in Table 4 with a dropper. did. Finally, it was filtered with a filter having a pore diameter of 1.2 μm to obtain a water-based ink. Table 4 shows the evaluation results of the obtained water-based ink.

  From the results of Table 4, it can be seen that the water-based inks of the examples are superior in adhesion to PET and PP and gloss as compared with the water-based inks of the comparative examples.

Claims (8)

A water-based ink for ink jet recording containing a colorant and polyester resin particles (A),
The polyester resin constituting the polyester resin particles (A) contains a composite resin in which a segment (A1) made of a polyester resin and a segment (A2) made of an addition polymerization resin are covalently bonded,
The segment (A2) is a structural unit (A2-1) derived from at least one of an acrylate ester having an alkyl group having 12 to 18 carbon atoms and a methacrylate ester having an alkyl group having 12 to 18 carbon atoms. Is a water-based ink for ink-jet recording, containing 5% by mass or more and 50% by mass or less in the segment (A2).   The water-based ink for inkjet recording according to claim 1, wherein the segment (A2) contains a structural unit (A2-2) derived from a styrene-based compound in the segment (A2) in an amount of 50% by mass to 95% by mass. .   The aqueous ink for inkjet recording according to claim 1 or 2, wherein the segment (A2) is 5% by mass or more and 50% by mass or less in the composite resin. The segment (A1) is a polyester resin obtained by polycondensation of an alcohol component and a carboxylic acid component,
The water-based ink for inkjet recording according to any one of claims 1 to 3, wherein the alcohol component contains 50 mol% or more and 100 mol% or less of an alkylene oxide adduct of bisphenol A.   The water-based ink for inkjet recording according to any one of claims 1 to 4, wherein the polyester resin particles (A) have a volume average particle diameter of 50 nm or more and 300 nm or less.   The water-based ink for inkjet recording according to any one of claims 1 to 5, wherein the content of the polyester resin particles (A) is 1% by mass or more and 15% by mass or less in the water-based ink. The manufacturing method of the water-based ink for inkjet recording in any one of Claims 1-6 including following process (1)-(3).
Step (1): A step of polymerizing raw material monomers of segment (A1) and segment (A2) to obtain a composite resin Step (2): mixing the composite resin obtained in step (1) with an aqueous medium, Step of obtaining an aqueous dispersion containing polyester resin particles (A) Step (3): An aqueous dispersion containing polyester resin particles (A) obtained in step (2) and an aqueous solution containing a colorant. Step of mixing with a dispersion to obtain a water-based ink for inkjet recording   An ink jet recording method, wherein the water based ink for ink jet recording according to claim 1 is attached to a resin recording medium by an ink jet recording method, and then the resin recording medium is heated to 70 ° C or higher and 150 ° C or lower. .