JP6052058B2 - Water-based ink set for inkjet recording - Google Patents

Description

  The present invention relates to a water-based ink set for inkjet recording.

  Printing with an inkjet printer recording device is a method that ejects ink from nozzles and adheres to the recording material. Unlike conventional printing methods, this is a printing method that does not use a plate, so on-demand printing that can accommodate a small variety of products This printing method is expected to be used in a wide range of fields. Particularly in recent years, as a recording material, there have been many studies on printing on a non-absorbing substrate such as plastic from printing on a conventional absorbing substrate such as paper, and printing using pigment inks from the viewpoint of weather resistance, among others. Is being studied.

  In the case of printing using a plastic film as the recording material, since the plastic is non-absorbent, the use of water-based ink significantly reduces the drying property, resulting in non-uniform spreading of the ink when the ink is deposited. As a result, there are problems such as blurring of images such as bleeding and intercolor bleeding, and deterioration in image quality due to failure to obtain good color development. For this reason, usually, a receiving layer is provided on a plastic film (for example, refer to Patent Document 1). However, the surface of the plastic film has poor adhesion to the ink-jet ink, and a layer usually called an anchor layer, primer layer, undercoat layer, adhesive layer, etc. is formed on the film surface, and polyurethane, polyacryl, etc. The step of providing an ink receiving layer containing as a main component was essential. Such a surface treatment process not only leads to an increase in cost, but also requires a lot of time for production because the number of processes increases.

On the other hand, as a printing method of an aqueous inkjet recording method that is excellent in image quality and abrasion resistance and excellent in discharge stability regardless of ink absorption of the recording medium with respect to a non-absorbing substrate such as plastic, color ink, resin A printing method for printing an image by applying ink and reactive ink is known (see, for example, Patent Document 2). Specifically, a color ink containing a water-insoluble colorant, a water-soluble and / or water-insoluble resin component, a water-soluble solvent, and a surfactant, a water-soluble resin solvent, and water-soluble but not soluble in water. The resin resin solvent contains thermoplastic resin particles that are compatible, and the total content of the resin particles is greater than or equal to the content of the colorant contained in the color ink; a polyvalent metal salt; Three inks of a reactive agent selected from allylamine and its derivatives and a reactive ink containing a surfactant are applied to form an image.
However, this method must prepare at least three kinds of inks, and requires an ink jet apparatus having a high degree of ejection accuracy.

  Also, as a two-component printing method using two kinds of inks, a step of applying a liquid composition containing a cationic substance and an ink containing an anionic substance to a recording medium so as to contact each other on the recording medium There is known a method of eliminating image disturbance such as bleeding and intercolor bleeding by a printing method having a color (for example, see Patent Document 3). However, even in this method, as described above, although subtle gradations can be reproduced with an absorbing base material such as paper, there is a problem in that image disturbance still cannot be eliminated by printing on a non-absorbing base material such as plastic. It remained.

Japanese Patent Laid-Open No. 10-119428 JP 2010-115854 A JP 2000-43399 A

  An object of the present invention is to provide a two-component water-based ink set for ink-jet recording that is excellent in abrasion resistance immediately after printing without causing image disturbance such as bleeding and intercolor bleeding even when printed on a plastic film. .

  The present inventors have combined a first liquid ink containing a resin having a hydroxy group and / or a carboxyl group with a second ink containing a second ink containing a cationic polyurethane resin containing a specific structural unit. The above-mentioned problems were solved by using the water-based ink set for inkjet recording.

That is, the present invention is an ink set for ink jet recording using at least two kinds of inks, and the first ink contains a color material, a resin having a hydroxy group and / or a carboxyl group, a water-soluble solvent and / or water. Including
The second ink has the following general formula [I]

〔式（Ｉ）中、Ｒ_１は脂肪族環式構造を含んでいてもよいアルキレン鎖、２価フェノール類の残基、又はポリオキシアルキレン鎖であり、Ｒ_２及びＲ_３は、互いに独立して脂肪族環式構造を含んでいてもよいアルキル基であり、Ｒ_４は水素原子又は４級化反応により導入された４級化剤の残基であり、Ｘ⁻はアニオン性の対イオンである。〕
で示される構造単位を含有するカチオン性ポリウレタン樹脂（Ａ）、水溶性溶媒及び／または水を含むインクジェット記録用水性インクセットを提供する。

[In Formula (I), R ₁ is an alkylene chain which may contain an aliphatic cyclic structure, a residue of a dihydric phenol, or a polyoxyalkylene chain, and R ₂ and R ₃ are independent of each other. An alkyl group which may contain an aliphatic cyclic structure, R ₄ is a hydrogen atom or a residue of a quaternizing agent introduced by a quaternization reaction, X ⁻ is an anionic counter ion is there. ]
A water-based ink set for ink-jet recording comprising the cationic polyurethane resin (A) containing the structural unit represented by formula (I), a water-soluble solvent and / or water is provided.

  According to the present invention, it is possible to provide an aqueous ink set for ink jet recording that gives a printed matter that is excellent in abrasion resistance immediately after printing without causing image distortion such as bleeding or intercolor bleeding even when printed on a plastic film.

  In the water-based ink set for ink-jet recording of the present invention, the first ink is an ink containing a color material, a resin having a hydroxy group and / or a carboxyl group, a water-soluble solvent and / or water, and the second ink is: Formula [I]

[In Formula (I), R ₁ is an alkylene chain which may contain an aliphatic cyclic structure, a residue of a dihydric phenol, or a polyoxyalkylene chain, and R ₂ and R ₃ are independent of each other. An alkyl group which may contain an aliphatic cyclic structure, R ₄ is a hydrogen atom or a residue of a quaternizing agent introduced by a quaternization reaction, X ⁻ is an anionic counter ion is there. ]
An ink containing a cationic polyurethane resin (A) containing a structural unit represented by formula (I), a water-soluble solvent and / or water.
By overprinting both inks, the ink is quickly fixed to the substrate. As a result, it is possible to obtain an ink which is free from image disturbance such as bleeding and intercolor bleeding and has excellent abrasion resistance immediately after printing.

  Although the mechanism is not clear about fast fixing with respect to a printing material by overprinting both inks, the following is estimated. That is, the cationic polyurethane resin (A) is triggered to grow into a giant aggregate by intermolecular hydrogen bonding of the resin having a hydroxy group and / or a carboxyl group, and these are caused by interactions such as van der Waals force. There is a possibility that they will be bundled and entangled in a mesh shape, preventing movement of each other, losing fluidity, and being fixed on the surface of the printed matter. Alternatively, the resin having a hydroxy group and / or carboxyl group present in the first ink reacts with the cationic polyurethane resin (A) present in the second ink to be immobilized on the surface of the printed material. There is a possibility.

(Resin having a first ink hydroxy group and / or carboxyl group)
The first ink used in the present invention contains a color material, a resin having a hydroxy group and / or a carboxyl group, a water-soluble solvent and / or water.

  The resin having a hydroxy group and / or carboxyl group is not particularly limited as long as a conventionally known resin having a hydroxy group and / or carboxyl group may be used.

The resin having a hydroxy group and / or a carboxyl group in the present invention may have a resin having at least a hydroxy group and / or a carboxyl group. The acquisition form of the resin which has the said carboxyl group is not specifically limited. In view of ease of handling, a dispersion of a resin in a water-soluble solvent and / or water, that is, a so-called resin emulsion is preferably used rather than a solid. Commercially available resin emulsions may also be used.
Among these, a resin characterized in that resin particles of polyolefin resin, polyester resin, polyester urethane resin, acrylic resin, vinyl chloride resin, vinyl acetate resin, or epoxy resin are dispersed in a water-soluble solvent and / or water. An emulsion is preferable, and a resin emulsion in which resin particles of a polyolefin resin are dispersed in a water-soluble solvent and / or water is more preferable.

  The content (% by mass) of the resin having a hydroxy group and / or a carboxyl group in the first ink is 2.0% by mass or more and 15.0% by mass or less based on the total mass of the ink. Preferably, 3.0 mass% or more and 8.0 mass% or less are still more preferable, and 3.0 mass% or more and 5.0 mass% or less are still more preferable.

The acid value of the resin having a hydroxy group and / or a carboxyl group is preferably 10 to 200 mgKOH / g per resin solid content. If the acid value is less than 10 mgKOH / g, the storage stability of the ink may be inferior. On the other hand, when the acid value exceeds 200 mgKOH / g, physical properties such as preferable durability and water resistance may not be obtained.
More preferably, it is the range of 5-100 mgKOH / g, More preferably, it is the range of 10-80 mgKOH / g, More preferably, it is the range of 15-60 mgKOH / g.

The hydroxyl value of the resin having a hydroxy group and / or a carboxyl group is preferably 30 mgKOH / g or less per resin solid content. If the hydroxyl value exceeds 30 mgKOH / g, the storage stability of the ink may be inferior. More preferably, it is 20 mgKOH / g or less, More preferably, it is 10 mgKOH / g or less.
In addition, the acid value and hydroxyl value here are the values measured by the method based on JIS0070.

  Moreover, it is preferable to set suitably the glass transition temperature (henceforth Tg) of resin which has the said hydroxyl group and / or carboxyl group according to the desired use. For example, when printing on a plastic film having flexibility such as for packaging materials for foods, flexibility (flexibility) is required, so that Tg is preferably not so high. In order to achieve both good adhesion to an appropriate film and flexibility, the Tg of the resin having a hydroxy group and / or a carboxyl group is preferably in the range of -80 ° C to 80 ° C, and -80 ° C to A range of 30 ° C. is particularly preferable.

The resin having a hydroxy group and / or carboxyl group has a weight average molecular weight (polystyrene conversion) of 10,000 or more and 1,000,000 or less, more preferably 20,000 or more and 700,000 or less. This is preferable because a physical property balance is easily developed.
In addition, the weight average molecular weight (Mw) here shall be calculated | required by GPC measurement on the following conditions.

[GPC measurement conditions]
Measuring device: “HLC-8220GPC” manufactured by Tosoh Corporation
Column: Guard column “SuperHZ-L” manufactured by Tosoh Corporation (inner diameter 4.6 mm × 2 cm)
+ Tosoh Corporation “TSKgelSuperHZ4000” (inner diameter 4.6 mm × 15 cm)
+ "TSKgelSuperHZ3000" manufactured by Tosoh Corporation (inner diameter 4.6 mm x 15 cm)
+ Tosoh Corporation “TSKgelSuperHZ2000” (inner diameter 4.6 mm × 15 cm)
+ "TSKgelSuperHZ1000" manufactured by Tosoh Corporation (inner diameter 4.6 mm x 15 cm)
Measurement conditions: Column temperature 40 ° C
Flow rate 0.35 ml / min Sample: A resin aqueous solution was dried and solidified, and a 0.5 mass% tetrahydrofuran (THF) solution in terms of resin solid content was filtered through a microfilter (10 μl).
Calibration curve: Monodisperse standard polystyrene STK standard polystyrene (manufactured by Tosoh Corporation) A calibration curve with samples having a molecular weight of 4000000 to 250 was used.

In the case of a resin composition in which the resin having a hydroxy group and / or carboxyl group used in the present invention is dispersed in a water-soluble solvent and / or water, such as a so-called resin emulsion, if the average particle size is too large, head clogging may occur. It causes discharge failure. Therefore, it is preferable that the average particle size of the resin particles having a hydroxy group and / or a carboxyl group is as small as possible because the influence on ejection failure is small. Specifically, the range of 10 nm to 500 nm is preferable, and the range of 10 to 300 nm is particularly preferable.
Here, the particle diameter can be measured by a known and common centrifugal sedimentation method, laser diffraction method (light scattering method), ESA method, capillary method, electron microscope method, or the like. Preferable is measurement by Microtrac UPA using a dynamic light scattering method.

  The resin emulsion that can be used in the ink of the present invention may contain an emulsifier without particular limitation as long as the desired physical properties are not impaired. For example, it may be a resin emulsion obtained by a method of dropping a monomer and a polymerization initiator in the presence of an emulsifier and polymerizing, or an emulsification method by stirring an aqueous solution or suspension of a resin. Of course, resin emulsions without addition of an emulsifier may be obtained by making full use of various emulsification / dispersion techniques such as an ultrasonic irradiation technique. As emulsifiers, nonionic emulsifiers such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, polyoxyethylene sorbitan alkyl esters, polyoxyethylene alkyl ether carboxylates, dialkyl sulfosuccinates, water-soluble acrylic resins Carboxylic acid types such as polycarboxylic acid salts, sulfonic acid types such as alkylbenzene sulfonates, anionic emulsifiers such as alcohol sulfate esters and alkylallyl sulfonates.

The polyolefin resin in the present invention has a polar group such as an amino group, a carboxyl group, and a hydroxyl group via a covalent bond to a hydrophobic polyolefin skeleton within a range that does not impair the effects of the present invention, depending on the desired physical properties, It can be set as the modified polyolefin which introduce | transduced the polymer chain.
As a method for producing a modified polyolefin, that is, a method for introducing a polar group or a polymer chain via a covalent bond to a polyolefin skeleton, a method for polymerizing a monomer having a polar group in the presence of a polyolefin, or a method for polymerizing a polymer chain into a polyolefin. Examples of the method include bonding. Depending on the properties of the target resin emulsion, the types and combinations of polyolefins, polar group-containing monomers and polymer chains can be appropriately selected. In other words, the chemical structure classification of the modified polyolefin is not particularly limited, and may be any of a random copolymer, a block copolymer, a graft modified product, and the like. As the polyolefin, any of a polyolefin having no reactive group or a polyolefin having a reactive group can be used.

  As the polyolefin having no reactive group, various known polyolefins and modified polyolefins can be used, and are not particularly limited. For example, ethylene or propylene homopolymer, ethylene / propylene copolymer, ethylene or / And copolymers of propylene and other comonomers. Examples of the comonomer include α-olefin comonomers having 2 or more carbon atoms such as butene-1, pentene-1, hexene-1, heptene-1, octene-1, cyclopentene, cyclohexene, and norbornene. The α-olefin comonomer is preferably an α-olefin comonomer having 2 to 8 carbon atoms, more preferably an α-olefin comonomer having 2 to 6 carbon atoms, and still more preferably an α-olefin comonomer having 2 to 4 carbon atoms. It is.

  Alternatively, two or more kinds of these α-olefin comonomers can also be used. Also, a hydrogenated product of a copolymer of two or more monomers selected from a copolymer of an α-olefin monomer and a comonomer such as vinyl acetate, acrylic acid ester, and methacrylic acid ester, and an aromatic vinyl monomer and a conjugated diene monomer. , Etc. can also be used. In addition, when only calling it a copolymer, it may be a random copolymer or a block copolymer. The polyolefin may be linear or branched.

  Furthermore, chlorinated polyolefins obtained by chlorinating these polyolefins can also be used. The chlorination degree of the chlorinated polyolefin is usually 5% by weight or more, preferably 10% by weight or more, and the chlorination degree is usually 50% by weight or less, preferably 30% by weight or less. However, for the purpose of reducing the environmental load, it is desirable that the polyolefin does not substantially contain chlorine. “Substantially no chlorine” means, for example, that the chlorination rate of polyolefin is less than 5% by weight.

  Examples of the polyolefin having a reactive group include a copolymer obtained by copolymerizing an unsaturated compound having no reactive group and an unsaturated compound having a reactive group at the time of polyolefin polymerization, or radical polymerization having a reactive group. A polymer obtained by graft polymerization of a polymerizable unsaturated compound onto a polyolefin, or a polymer obtained by converting a polyolefin having an unsaturated end group into an element group of group 13 to group 17 can be used.

  Examples of the reactive group include a carboxylic acid group, a dicarboxylic acid anhydride group, and a dicarboxylic acid anhydride monoester group, a hydroxyl group, an amino group, an epoxy group, an isocyanate group, and the like, and a carboxylic acid group and a dicarboxylic acid anhydride group. And a dicarboxylic anhydride monoester group is more preferred. Carboxylic acid groups, dicarboxylic acid anhydride groups, and dicarboxylic acid anhydride monoester groups are not only highly reactive and easy to bond with hydrophilic polymers, but also contain many unsaturated compounds having these groups and are common to polyolefins. This is because polymerization or graft reaction is also easy, and so-called acid-modified polyolefin resins in which polyolefin has these groups are excellent in water dispersibility.

A copolymer obtained by copolymerizing an unsaturated compound having no reactive group at the time of polyolefin polymerization and an unsaturated compound having a reactive group is a copolymer in which an unsaturated compound having a reactive group is inserted into the main chain. It is. For example, α-olefin such as ethylene, propylene, butene, (meth) acrylic acid, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylamide, (meth) acrylic acid (dimethylamino) ) Ethyl, (meth) acrylic acid (2-isocyanato) ethyl, and α, β-unsaturated carboxylic acid such as maleic anhydride, the same ester or anhydride. (In the present invention, “(meth) acrylic acid” means “acrylic acid or methacrylic acid”).)
Specific examples of these copolymers include propylene-butene-maleic anhydride copolymers. These may be used individually by 1 type and may be used in combination of 2 or more type. Of course, it is also possible to use a commercially available product.

  A polymer obtained by graft-polymerizing a radically polymerizable unsaturated compound having a reactive group to a polyolefin is obtained by graft-polymerizing a radically polymerizable unsaturated compound having a reactive group to a previously polymerized polyolefin. The unsaturated compound it has is grafted to the main chain. For example, polyolefins such as polyethylene and polypropylene, (meth) acrylic acid, fumaric acid, maleic acid or anhydride thereof, itaconic acid or anhydride thereof, crotonic acid, 2-hydroxyethyl (meth) acrylate and (meth) acrylic acid It is a polymer grafted with 2-hydroxypropyl, (meth) acrylamide, (meth) acrylic acid (dimethylamino) ethyl, (meth) acrylic acid glycidyl, (meth) acrylic acid (2-isocyanato) ethyl, or the like. These may be used individually by 1 type and may be used in combination of 2 or more type. As polyolefin of this reaction, the polyolefin which does not have the above-mentioned reactive group can be used.

  Specific examples of a polymer obtained by graft polymerization of a radically polymerizable unsaturated compound having a reactive group onto a polyolefin include, for example, maleic anhydride-modified polypropylene and its chlorinated product, maleic anhydride-modified propylene-ethylene copolymer and its chlorine. , A maleic anhydride modified propylene-butene copolymer and its chlorinated product, an acrylic acid modified polypropylene and its chlorinated product, an acrylic acid modified propylene-ethylene copolymer and its chlorinated product, an acrylic acid modified propylene-butene copolymer and Examples thereof include chlorinated substances. These may be used individually by 1 type and may be used in combination of 2 or more type.

  The radical polymerization initiator used for the graft polymerization can be appropriately selected from ordinary radical initiators, such as organic peroxides such as benzoyl peroxide and t-butylperoxyisopropyl monocarbonate, azonitrile, etc. Can be mentioned. These may be used individually by 1 type and may be used in combination of 2 or more type.

  A method for producing a polymer obtained by graft polymerization of a radically polymerizable unsaturated compound having a reactive group onto a polyolefin is not particularly limited, and any production method may be used. For example, solution modification method (method of reacting by heating and stirring in a solution), melt modification method (method of reacting by melting and heating and stirring without a solvent, or method of reacting by heating and kneading with an extruder), etc. It is done.

  A polymer obtained by converting a polyolefin having an unsaturated end group into an element group of group 13 to group 17 is, for example, a double bond of a polyolefin having a terminal double bond as described in JP-A-2001-288372. A polyolefin having part thereof converted into a group 13 element group such as a boron group or an aluminum group, and a double bond part of a polyolefin having a terminal double bond as described in JP-A-2005-48172 is converted to a halogen element. Polyolefin, a polyolefin obtained by converting a double bond portion of a propylene-based polymer having a terminal double bond into a mercapto group as described in JP-A-2001-98140 can be used. Usually, a block copolymer is used as a block copolymer. Can be obtained.

  The polymer chain to be introduced into the hydrophobic polyolefin skeleton via a covalent bond can be used without particular limitation as long as the effects of the present invention are not impaired, depending on the desired physical properties. It may be linear or branched. For example, synthetic polymer such as poly (meth) acrylic resin, polyester resin, polyether resin, polyvinyl alcohol resin, polyvinylpyrrolidone resin, semi-synthetic polymer such as cationic starch, dextrin, hydroxyethyl cellulose, agar, gum arabic, gelatin, etc. Any of these natural polymers can be used. The polymer chain may have a reactive group.

  For the polymer chain, it is preferable to use a synthetic polymer because stable physical properties are easily obtained. Among these, poly (meth) acrylic resins, polyester resins, polyether resins, polyvinyl alcohol resins, and polyvinylpyrrolidone resins are more preferable, and amphiphilic polyether resins are even more preferable. These may be used individually by 1 type and may be used in combination of 2 or more type.

  The poly (meth) acrylic resin used for the polymer chain is obtained by polymerizing an unsaturated carboxylic acid or an ester or anhydride thereof by radical polymerization, anionic polymerization, or cationic polymerization. Examples of the unsaturated carboxylic acid or ester or anhydride thereof include (meth) acrylic acid, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylamide, and (meth) acrylic acid (dimethyl). Amino) ethyl, (meth) acrylic acid (2-isocyanato) ethyl, maleic anhydride and the like. In addition, depending on the desired physical properties, a hydrophobic radical polymerizable compound (hydrophobic monomer) is used in order to provide good adhesion to various thermoplastic resin film substrates within a range that does not impair the effects of the present invention. Can be copolymerized. Examples of the copolymerizable hydrophobic monomer include a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, an aryl group or an arylalkyl group, and a hydrocarbon group having 1 to 12 carbon atoms. Examples thereof include polymerizable vinyl monomers.

  The polyvinyl alcohol resin used for the polymer chain can be usually obtained by polymerizing vinyl acetate to obtain polyvinyl acetate and then saponifying. The saponification degree may be complete saponification or partial saponification. Moreover, the polyvinyl pyrrolidone resin used for the polymer chain can be obtained by polymerizing vinyl pyrrolidone. Of course, a commercially available product may be used.

  The method for introducing the polymer chain into the polyolefin is not particularly limited. For example, a method of radical polymerization in the presence of a polyolefin, an acrylic system having a reactive group such as a hydroxyl group, an amino group, a glycidyl group, or an (anhydrous) carboxylic acid group. Examples thereof include a method of reacting a resin with a polyolefin having a reactive group.

  A polyether resin having amphiphilic properties used as a polymer chain introduced into a hydrophobic polyolefin skeleton via a covalent bond can be obtained by ring-opening polymerization of cyclic alkylene oxide or cyclic alkylene imine. The method for bonding with polyolefin is not particularly limited. For example, a method of ring-opening polymerization of cyclic alkylene oxide in a polyolefin having a reactive group, a reaction of polyether polyol or polyether amine obtained by ring-opening polymerization, etc. Examples thereof include a method of reacting a polyether resin having a reactive group with a polyolefin having a reactive group.

Polyetheramine is a compound having a primary amino group as a reactive group at one or both ends of a resin having a polyether skeleton. As the polyetheramine, Jeffamine M series, D series, ED series, etc. manufactured by Huntsman, USA may be used.
Polyether polyol is a compound having hydroxyl groups as reactive groups at both ends of a resin having a polyether skeleton. Preferred examples of the polyalkylene oxide and polyalkyleneimine exhibiting hydrophilicity include polyethylene oxide, polypropylene oxide, and polyethyleneimine.

One or more reactive groups may be used, but it is more preferable to have only one reactive group. This is because when there are two or more reactive groups, there is a possibility that a three-dimensional network structure will be formed upon bonding with the polyolefin, resulting in gelation. However, even if it has a plurality of reactive groups, the gelation described above can be avoided if there is only one reactive group having a higher reactivity than others. For example, a hydrophilic polymer having a plurality of hydroxyl groups and one amino group having a higher reactivity is one preferred example. The reactivity here is the reactivity with the reactive group which polyolefin has.
As the polyolefin resin in the present invention, an olefin resin marketed as an aqueous dispersion can be preferably used. For example, the Hardren series manufactured by Toyobo Co., Ltd., the Aptolock series manufactured by Mitsubishi Chemical Corporation, the Allobase series manufactured by Unitika Ltd., etc. can be used.

(First ink coloring material)
The color material used in the present invention is not particularly limited, and color materials usually used in water-based inkjet inks can be used, and examples thereof include pigments and dyes.
If the application requires weather resistance and water resistance, it is preferable to use a pigment. As the pigment, known and commonly used organic pigments or inorganic pigments can be used.

The pigment used in the present invention is at least one pigment selected from known and commonly used organic pigments or inorganic pigments. In addition, the present invention can be applied to either an untreated pigment or a treated pigment.
In the case of printing using plastic as a recording material, as ink-jet ink, in addition to yellow ink, cyan ink, magenta ink, black ink, etc., white ink is also used for the purpose of improving visibility. These pigments used are not particularly limited, and those usually used as pigments for water-based inkjet recording inks can be used. Specifically, it can be dispersed in water or a water-soluble organic solvent, and a known inorganic pigment or organic pigment can be used. Examples of the inorganic pigment include carbon black produced by a known method such as iron oxide, a contact method, a furnace method, and a thermal method. Organic pigments include azo pigments (including azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments), polycyclic pigments (for example, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazines). Pigments, thioindigo pigments, isoindolinone pigments, quinofullerone pigments, etc.), dye chelates (for example, basic dye chelates, acidic dye chelates, etc.), nitro pigments, nitroso pigments, aniline black, and the like.

  For example, the pigment used in the black ink is carbon black, No. manufactured by Mitsubishi Chemical Corporation. 2300, no. 2200B, no. 900, no. 960, no. 980, no. 33, no. 40, No, 45, No. 45L, no. 52, HCF88, MA7, MA8, MA100, etc. are Raven5750, Raven5250, Raven5000, Raven3500, Raven1255, Raven700, etc. manufactured by Columbia, Regal400R, Regal330R, Regal660R, MoulMar800, Rul700 , Monarch 1000, Monarch 1100, Monarch 1300, Monarch 1400, etc. are ColorBlack FW1, FW2, FW2V, FW18, FW200, S150, S160, S170, Printex35, U, la, lc, iB, p6c 5 The 4, the 4A, NIPEX150, NIPEX160, NIPEX170, NIPEX180 and the like.

  Specific examples of pigments used in yellow ink include C.I. I. Pigment Yellow 1, 2, 12, 13, 14, 16, 17, 73, 74, 75, 83, 93, 95, 97, 98, 109, 110, 114, 120, 128, 129, 138, 150, 151, 154, 155, 174, 180, 185 and the like.

  Specific examples of pigments used in magenta ink include C.I. I. Pigment Red 5, 7, 12, 48 (Ca), 48 (Mn), 57 (Ca), 57: 1, 112, 122, 123, 146, 168, 176, 184, 185, 202, 209, etc. It is done.

  Specific examples of pigments used for cyan ink include C.I. I. Pigment blue 1, 2, 3, 15, 15: 3, 15: 4, 16, 22, 60, 63, 66, and the like.

  Specific examples of pigments used in white inks include silicas such as alkaline earth metal sulfates, carbonates, finely divided silicic acids, synthetic silicates, calcium silicates, alumina, alumina hydrates, Examples thereof include titanium oxide, zinc oxide, talc, and clay. The inorganic white pigment may be surface-treated by various surface treatment methods.

  Examples of the dye include C.I. I. Acid Black 1, 2, 7, 16, 17, 24, 26, 28, 31, 41, 48, 52, 58, 60, 63, 94, 107, 109, 112, 118, 119, 121, 122, 131, 155, 156; C.I. I. Acid Yellow 1, 3, 4, 7, 11, 12, 13, 14, 17, 18, 19, 23, 25, 29, 34, 38, 40, 41, 42, 44, 49, 53, 55, 59, 61, 71, 72, 76, 78, 79, 99, 111, 114, 116, 122, 135, 142, 161, 172; I. Acid Orange 7, 8, 10, 19, 20, 24, 28, 33, 41, 45, 51, 56, 64; C.I. I. Acid Red 1, 4, 6, 8, 13, 14, 15, 18, 19, 21, 26, 27, 30, 32, 34, 35, 37, 40, 42, 44, 51, 52, 54, 57, 80, 82, 83, 85, 87, 88, 89, 92, 94, 97, 106, 108, 110, 111, 114, 115, 119, 129, 131, 133, 134, 135, 143, 143: 1, 144, 152, 154, 155, 172, 176, 180, 184, 186, 187, 249, 254, 256, 289, 317, 318; I. Acid Violet 7, 11, 15, 34, 35, 41, 43, 49, 51, 75; I. Acid Blue 1, 7, 9, 15, 22, 23, 25, 27, 29, 40, 41, 43, 45, 49, 51, 53, 55, 56, 59, 62, 78, 80, 81, 83, 90, 92, 93, 102, 104, 111, 113, 117, 120, 124, 126, 138, 145, 167, 171, 175, 183, 229, 234, 236, 249; I. Acid Green 3, 9, 12, 16, 19, 20, 25, 27, 41, 44; C.I. I. Acid dyes such as Acid Brown 4 and 14,

C. I. Basic Black 2.8; C.I. I. Basic yellow 1, 2, 11, 12, 14, 21, 32, 36; I. B. Basic Orange 2, 15, 21, 22; I. Basic Red 1, 2, 9, 12, 13, 37; I. C. basic violet 1, 3, 7, 10, 14; I. Basic blue 1, 3, 5, 7, 9, 24, 25, 26, 28, 29; I. Basic green 1, 4; basic dyes such as basic brown 1 and 12,

C. I. Direct Black 2, 4, 9, 11, 14, 17, 19, 22, 27, 32, 36, 38, 41, 48, 49, 51, 56, 62, 71, 74, 75, 77, 78, 80, 105, 106, 107, 108, 112, 113, 117, 132, 146, 154, 168, 171, 194; C. Direct yellow 1, 2, 4, 8, 11, 12, 24, 26, 27, 28, 33, 34, 39, 41, 42, 44, 50, 51, 58, 72, 85, 86, 87, 88, 98, 100, 110, 127, 135, 141, 142, 144; C.I. I. Direct orange 6, 8, 10, 26, 29, 41, 49, 52, 102; I. Direct Red 1, 2, 4, 8, 9, 11, 13, 15, 17, 20, 23, 24, 28, 31, 33, 37, 39, 44, 46, 47, 48, 51, 59, 62, 63, 73, 75, 77, 80, 81, 83, 84, 85, 87, 89, 90, 94, 95, 99, 101, 108, 110, 145, 189, 197, 220, 224, 225, 226, 227, 230, 250, 254, 256, 257; I. Direct violet 1, 7, 9, 12, 35, 48, 51, 90, 94; I. Direct Blue 1, 2, 6, 8, 15, 22, 25, 34, 69, 70, 71, 72, 75, 76, 78, 80, 81, 82, 83, 86, 90, 98, 106, 110, 110, 120, 123, 158, 163, 165, 192, 193, 194, 195, 196, 199, 200, 201, 202, 203, 207, 218, 236, 237, 239, 246, 258, 287; Direct Green 1, 6, 8, 28, 33, 37, 63, 64; C.I. I. Direct dyes such as Direct Brown 1A, 2, 6, 25, 27, 44, 58, 95, 10, 101, 106, 112, 173, 194, 195, 209, 210, 211,

C. I. Reactive black 1, 3, 5, 6, 8, 12, 14; I. Reactive yellow 1, 2, 3, 13, 14, 15, 17; I. Reactive Orange 2, 5, 7, 16, 20, 24; Reacted Bread 6, 7, 11, 12, 15, 17, 21, 23, 24, 35, 36, 42, 63, 66, 84, 184 C. I. Reactive violet 2, 4, 5, 8, 9; I. Reactive Blue 2, 5, 7, 12, 13, 14, 15, 17, 18, 19, 20, 21, 25, 27, 28, 37, 38, 40, 41; C.I. I. Reactive dyes 5, 7; reactive dyes such as reactive brown 1, 7, 16, etc.

C. I. Food black 1, 2; I. Food yellow 3, 4, 5; I. Food red 2, 3, 7, 9, 14, 52, 87, 92, 94, 102, 104, 105, 106; I. Food violet 2; C.I. I. Food blue 1, 2; C.I. I. Examples include food dyes such as Food Green 2 and 3.

In the present invention, a so-called self-dispersing pigment (surface-treated pigment) having a water dispersibility-imparting group on the pigment surface and capable of stably maintaining the dispersion state without a dispersant may be used. So-called capsule pigments (water-dispersible polymer-containing pigments) that can be stably maintained without a dispersant, or pigments dispersed with a dispersant may be used.
The average particle size of the pigment is preferably a particle size usually used for inkjet inks, specifically 50 to 500 nm is preferable, and 50 to 300 nm is more preferable for color ink.

The pigment may be dispersed in water using a known and commonly used pigment dispersant or binder, or a surfactant may be used.
The pigment dispersant is preferably an aqueous resin, and preferable examples include polyvinyl alcohols, polyvinylpyrrolidones, acrylic resins such as acrylic acid-acrylic acid ester copolymers, styrene-acrylic acid copolymers, styrene-methacrylic acid. Styrene such as acid copolymer, styrene-methacrylic acid-acrylic acid ester copolymer, styrene-α-methylstyrene-acrylic acid copolymer, styrene-α-methylstyrene-acrylic acid-acrylic acid ester copolymer Examples thereof include acrylic resins, styrene-maleic acid copolymers, styrene-maleic anhydride copolymers, vinylnaphthalene-acrylic acid copolymers, and salts of the aqueous resins.
The compounds for forming the copolymer salt include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide and lithium hydroxide, and diethylamine, ammonia, ethylamine, triethylamine, propylamine, isopropylamine, Examples include propylamine, butylamine, isobutylamine, triethanolamine, diethanolamine, aminomethylpropanol, and morpholine. The amount of the compound used to form these salts is preferably equal to or greater than the neutralization equivalent of the copolymer.
Of course, it is also possible to use a commercial item. As a commercially available product, Ajinomoto Fine Techno Co., Ltd. product Ajisper PB series, Big Chemie Japan Co., Ltd. Disperbyk series, BYK-series, Ciba Specialty Chemicals EFKA series, etc. can be used.

(First ink water-soluble solvent and / or water)
The water-soluble solvent and / or water used in the present invention may be water alone or a mixed solvent composed of water and a water-soluble solvent. Examples of the water-soluble solvent include ketones such as acetone, methyl ethyl ketone, methyl butyl ketone, and methyl isobutyl ketone; methanol, ethanol, 2-propanol, 2-methyl-1-propanol, 1-butanol, 2-methoxyethanol, Alcohols such as tetrahydrofuran; 1,4-dioxane, ethers such as 1,2-dimethoxyethane; and amides such as dimethylformamide and N-methylpyrrolidone, especially those having 3 to 6 carbon atoms It is preferable to use a compound selected from the group consisting of a ketone and an alcohol having 1 to 5 carbon atoms.

(First ink production method)
The first ink used in the present invention is to prepare a dispersion (pigment paste) of the pigment, dilute it with water, add the resin having the hydroxy group and / or carboxyl group, and wet as necessary. An ink can be prepared by adding an agent (drying inhibitor), a penetrating agent, or other additives.

(Pigment paste)
The method for preparing the pigment paste is not particularly limited, and examples thereof include known methods. For example, the following method can be mentioned.
(1) A method of preparing a pigment paste by adding a pigment to an aqueous medium containing a pigment dispersant and water and then dispersing the pigment in the aqueous medium using a stirring / dispersing device.
(2) The pigment and the pigment dispersant are kneaded using a kneader such as two rolls or a mixer, and the resulting kneaded product is added to an aqueous medium containing water, and the pigment is then mixed using a stirring / dispersing device. A method of preparing a paste.
(3) After adding a pigment to a solution obtained by dissolving a pigment dispersant in an organic solvent compatible with water such as methyl ethyl ketone and tetrahydrofuran, the pigment is added to the organic solution using a stirring / dispersing device. And then phase-emulsifying using an aqueous medium, and then the organic solvent is distilled off to prepare a pigment paste.
(4) After adding a pigment to a solution obtained by dissolving a pigment dispersant in an organic solvent compatible with water, such as methyl ethyl ketone, tetrahydrofuran, etc., the pigment is added to the organic solution using a stirring / dispersing device. A pigment paste is prepared by dispersing in water, then neutralizing with a basic compound and dispersing in water.
(5) After adding a pigment to a solution obtained by dissolving a pigment dispersant in an organic solvent compatible with water, such as methyl ethyl ketone and tetrahydrofuran, the pigment is added to the organic solution using a stirring / dispersing device. Then, after neutralizing with a basic compound and dispersing in water, an acidic compound is added to make the pigment dispersant hydrophobic, thereby fixing the pigment dispersant to the pigment. A method of preparing a pigment paste by an analysis method.

  Examples of the agitation / dispersing device include an ultrasonic homogenizer, a high-pressure homogenizer, a paint shaker, a ball mill, a roll mill, a sand mill, a sand grinder, a dyno mill, a disperse mat, an SC mill, and a nanomizer. May be used alone, or two or more kinds of apparatuses may be used in combination.

  Moreover, as a kneading machine, a 2 roll, a Henschel mixer, a pressure kneader, a Banbury mixer, a planetary mixer, etc. can be raised, One of these may be used independently and 2 or more types of apparatuses may be used. You may use it in combination.

  The amount of pigment in the pigment paste is preferably 5 to 60% by mass, and more preferably 10 to 50% by mass. When the pigment amount is less than 5% by mass, the water-based ink prepared from the pigment paste is insufficiently colored, and a sufficient image density tends not to be obtained. On the other hand, when the amount is more than 60% by mass, the dispersion stability of the pigment tends to decrease in the pigment paste.

  In addition, in the ink preparation example, coarse particles cause nozzle clogging and other image characteristics, and therefore it is preferable to remove the coarse particles by centrifugation or filtration after ink preparation. .

(Wetting agent)
The wetting agent is added for the purpose of preventing the ink from drying. The content of the wetting agent in the ink for the purpose of preventing drying is preferably 3 to 50% by mass.
The wetting agent used in the present invention is not particularly limited, but a wetting agent that is miscible with water and can prevent clogging of the head of an inkjet printer is preferable. For example, glycerin, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol having a molecular weight of 2000 or less, propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-propylene glycol, isopropylene glycol, isobutylene glycol, 1,4-butane Examples include diol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, mesoerythritol, pentaerythritol, and the like. Among them, the inclusion of propylene glycol and 1,3-butanediol is safe and has excellent effects in ink drying properties and ejection performance.

(Penetration agent)
The penetrant is added for the purpose of improving the permeability to a recording medium and adjusting the dot diameter on the recording medium. Examples of the penetrant include lower alcohols such as ethanol and isopropyl alcohol, ethylene oxide adducts of alkyl alcohols such as ethylene glycol hexyl ether and diethylene glycol butyl ether, and propylene oxide adducts of alkyl alcohols such as propylene glycol propyl ether.
The penetrant content in the ink is preferably 0.01 to 10% by mass.

(Surfactant)
The surfactant is added to adjust ink properties such as surface tension. The surfactant that can be added for this purpose is not particularly limited, and examples include various anionic surfactants, nonionic surfactants, cationic surfactants, and amphoteric surfactants. Of these, anionic surfactants and nonionic surfactants are preferred.

  Examples of the anionic surfactant include alkylbenzene sulfonate, alkylphenyl sulfonate, alkylnaphthalene sulfonate, higher fatty acid salt, sulfate of higher fatty acid ester, sulfonate of higher fatty acid ester, higher alcohol ether. Sulfate salts and sulfonates of the above, higher alkyl sulfosuccinates, polyoxyethylene alkyl ether carboxylates, polyoxyethylene alkyl ether sulfates, alkyl phosphates, polyoxyethylene alkyl ether phosphates, etc. Specific examples include dodecylbenzene sulfonate, isopropyl naphthalene sulfonate, monobutylphenylphenol monosulfonate, monobutylbiphenyl sulfonate, dibutylphenylphenol disulfate. , And the like salts.

  Nonionic surfactants include, for example, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, glycerin fatty acid ester , Polyoxyethylene glycerin fatty acid ester, polyglycerin fatty acid ester, sucrose fatty acid ester, polyoxyethylene alkylamine, polyoxyethylene fatty acid amide, fatty acid alkylolamide, alkyl alkanolamide, acetylene glycol, oxyethylene adduct of acetylene glycol, Polyethylene glycol polypropylene glycol block copolymer, etc. Among them, polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene alkyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, fatty acid Preference is given to alkylolamide, acetylene glycol, oxyethylene adducts of acetylene glycol and polyethylene glycol polypropylene glycol block copolymers.

  Other surfactants include silicone surfactants such as polysiloxane oxyethylene adducts; fluorine surfactants such as perfluoroalkyl carboxylates, perfluoroalkyl sulfonates, and oxyethylene perfluoroalkyl ethers. Biosurfactants such as spicrispolic acid, rhamnolipid, lysolecithin and the like can also be used.

  These surfactants can be used alone or in combination of two or more. In consideration of the dissolution stability of the surfactant, the HLB is preferably in the range of 7-20. When the surfactant is added, the addition amount is preferably in the range of 0.001 to 2% by mass, more preferably 0.001 to 1.5% by mass, based on the total mass of the ink. More preferably, it is in the range of 01 to 1% by mass. When the addition amount of the surfactant is less than 0.001% by mass, the effect of adding the surfactant tends to be not obtained, and when it exceeds 2% by mass, problems such as blurring of the image are likely to occur. .

  Moreover, antiseptic | preservative, a viscosity modifier, a pH adjuster, a chelating agent, a plasticizer, antioxidant, an ultraviolet absorber etc. can be added as needed.

  The amount of pigment in the ink jet recording ink prepared from the pigment paste is 1 to 20% by mass in order to obtain a sufficient image density and to ensure the dispersion stability of the pigment in the ink. preferable.

  In the present invention, the surface tension of the first ink is preferably 20 mN / m or more and 60 mN / m or less. More preferably, it is 20 mN / m or more and 45 mN / m or less, More preferably, it is 20 mN / m or more and 40 mN / m or less. If the surface tension is less than 20 mN / m, the liquid may overflow on the nozzle surface and printing may not be performed normally. On the other hand, when it exceeds 60 mN / m, there is a tendency that the non-absorbing base material is easily repelled.

In the present invention, the viscosity of the first ink is preferably 1.2 mPa · s or more and 20.0 mPa · s or less, more preferably 2.0 mPa · s or more and less than 15.0 mPa · s, and still more preferably 3. 0 mPa · s or more and less than 12.0 mPa · s. When the viscosity is within this range, it is possible to achieve excellent dischargeability and good jetability over a long period of time.
The surface tension and viscosity of the first ink can be maintained in the above preferred ranges by adjusting the type and amount of surfactant and water-soluble solvent to be contained.

(Second ink cationic polyurethane resin (A))
The second ink used in the present invention contains the cationic polyurethane resin (A). The cationic polyurethane resin (A) has a structural unit represented by the general formula [I] and forms an aqueous dispersion that is stably dispersed in an aqueous medium. The aqueous medium is not particularly limited as long as it is a homogeneous solvent system mainly containing water. Examples of such solvent systems include a solvent system in which an alcohol-based water-soluble organic solvent such as methanol, ethanol, isopropanol, and butanol is mixed with water, and an ether-based water-soluble organic solvent such as tetrahydrofuran and butyl cellosolve in water. And the solvent system used. The most preferred aqueous medium is an isopropanol / water mixed solvent system. The amount of the water-soluble organic solvent added is preferably 50% by mass or less with respect to the amount of water contained in the whole ink.

  The cationic polyurethane resin (A) is dispersed in a water-soluble solvent that is a solvent for the second ink and / or water. The average particle diameter of the dispersed resin particles is preferably 5 nm to 1000 nm, and more preferably 10 nm to 400 nm, from the viewpoint of ensuring stable ejection properties.

  The content of the cationic functional group in the general formula [I] is not particularly limited as long as the cationic polyurethane resin (A) can be formed in a stable dispersion without being dissolved in an aqueous medium. It is not limited. Accordingly, the cationic polyurethane resin (A) has a preferable cationic functional group content depending on the structure other than the general formula [I] such as molecular weight and branching degree. (A) If it contains 0.01-1 equivalent / kg as a cation equivalent in solid content, it can be set as an aqueous dispersion, and in particular to the dispersibility to the aqueous medium of cationic polyurethane resin (A). From the point which is excellent, it is preferable to contain 0.02-0.8 equivalent / kg, and it is especially preferable to contain 0.03-0.6 equivalent / kg.

  As the number average molecular weight (Mn) calculated by polystyrene conversion by gel permeation chromatography (GPC) of the cationic polyurethane resin (A), the cationic polyurethane resin (A) is stable without being dissolved in an aqueous medium. It is not particularly limited as long as the dispersion can be formed, and is usually in the range of 1,000 to 5,000,000, and preferably in the range of 5,000 to 1,000,000.

  The cationic polyurethane resin (A) can be produced by using various compounds, and a production method using an industrially easily available and inexpensive raw material is represented by the following general formula [IV]. A tertiary amino group-containing polyol (a) obtained by reacting a compound (a-1) having two epoxy groups in one molecule with a secondary amine (a-2) is a polyisocyanate (g) described later. The method of reacting with is most useful.

(In the formula [IV], R ₁ is an alkylene chain that may contain an aliphatic cyclic structure, a residue of a dihydric phenol, or a polyoxyalkylene chain.)

  The tertiary amino group-containing polyol (a) introduces a neutral salt of a tertiary amino group for imparting water dispersibility to the polyurethane resin or a cationic group such as a quaternary amino group into the side chain of the polyurethane resin skeleton. It is a compound used for

  The tertiary amino group-containing polyol (a) is a precursor for generating a cationic group by neutralizing the tertiary amino group contained in the molecule with an acid or quaternizing with a quaternizing agent. is there.

The tertiary amino group-containing polyol (a) includes, for example, a compound (a-1) having two epoxy groups in one molecule and a secondary amine (a-2), which is NH with respect to 1 equivalent of epoxy group. It can be easily obtained by blending so as to be 1 equivalent of a group and performing a ring-opening addition reaction at room temperature or under heating without using a catalyst.

  As the compound (a-1) having two epoxy groups in one molecule represented by the general formula [IV], the following compounds may be used alone or in combination of two or more.

As a raw material in the case of obtaining an alkylene chain which may contain an aliphatic cyclic structure as R ₁ , for example, ethanediol 1,2-diglycidyl ether, propanediol 1,2-diglycidyl ether, Propanediol 1,3-diglycidyl ether, butanediol 1,4-diglycidyl ether, pentanediol 1,5-diglycidyl ether, 3-methyl-pentanediol 1,5-diglycidyl ether, neopentyl glycol diglycidyl ether , Hexanediol 1,6-diglycidyl ether, polybutadiene glycol diglycidyl ether, cyclohexanediol 1,4-diglycidyl ether, diglycidyl of 2,2-bis (4-hydroxycyclohexyl) -propane (hydrogenated bisphenol A) Ether, diglycidyl ether of hydrogenated dihydroxydiphenylmethane isomer mixture (hydrogenated bisphenol F), and the like can be used.

In addition, as raw materials for obtaining those in which R ₁ is a residue of a dihydric phenol, for example, resorcinol-diglycidyl ether, hydroquinone-diglycidyl ether, 2,2-bis (4-hydroxyphenyl) -propane ( Diglycidyl ether of bisphenol A), diglycidyl ether of isomer mixture of dihydroxydiphenylmethane (bisphenol F), diglycidyl ether of 4,4′-dihydroxy-3-3′-dimethyldiphenylpropane, 4,4′-dihydroxydiphenyl Diglycidyl ether of cyclohexane, diglycidyl ether of 4,4′-dihydroxydiphenyl, diglycidyl ether of 4,4′-dihydroxydibenzophenone, diglycidyl ether of bis (4-hydroxyphenyl) -1,1-ethane, Of diglycidyl ether of bis (4-hydroxyphenyl) -1,1-isobutane, diglycidyl ether of bis (4-hydroxy-3-tertbutylphenyl) -2,2-propane, bis (2-hydroxynaphthyl) methane Diglycidyl ether, diglycidyl ether of bis (4-hydroxyphenyl) sulfone (bisphenol S), and the like can be used.

In addition, as raw materials for obtaining a polymer in which R ₁ is a polyoxyalkylene chain, for example, diethylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, and polyoxyalkylene glycol dioxyethylene having 3 to 60 repeating oxyalkylene units. Glycidyl ethers such as polyoxyethylene glycol diglycidyl ether and polyoxypropylene glycol diglycidyl ether, ethylene oxide-propylene oxide copolymer diglycidyl ether, polyoxytetraethylene glycol diglycidyl ether, and the like can be used.

Among these, since the water dispersibility of the cationic polyurethane resin can be further improved, the diglycidyl ether of polyoxyalkylene glycol in which R ₁ of the general formula [IV] is a polyoxyalkylene chain, It is preferable to use oxyethylene glycol diglycidyl ether and / or polyoxypropylene glycol diglycidyl ether and / or diglycidyl ether of ethylene oxide-propylene oxide copolymer.

The epoxy equivalent of the polyoxyalkylene glycol diglycidyl ether in which R ₁ of the general formula [IV] is a polyoxyalkylene chain is used as the cation concentration in the cationic polyurethane resin aqueous dispersion. In view of being able to be performed in a wide range, it is preferably 1000 g / equivalent or less, more preferably 500 g / equivalent or less, and particularly preferably 300 g / equivalent or less.

  In the above-described method, a secondary amine (a-2) is used to produce a tertiary amino group-containing polyol (a) by a ring-opening addition reaction with a compound (a-1) having two epoxy groups in one molecule. )is necessary.

  Although various compounds can be used as the secondary amine (a-2), a branched or straight chain aliphatic secondary amine is preferable from the viewpoint of easy reaction control.

  Examples of the secondary amine (a-2) that can be used include dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, di-n-butylamine, di-tert-butylamine, di- sec-butylamine, di-n-pentylamine, di-n-peptylamine, di-n-octylamine, diisooctylamine, dinonylamine, diisononylamine, di-n-decylamine, di-n-undecylamine, di- Examples include n-dodecylamine, di-n-pentadecylamine, di-n-octadecylamine, di-n-nonadecylamine, di-n-eicosylamine.

  Among these, it is difficult to volatilize when producing the tertiary amino group-containing polyol (a), or a part or all of the contained tertiary amino groups are neutralized with an acid, or 4 with a quaternizing agent. For reasons such as the ability to reduce steric hindrance when classifying, an aliphatic secondary amine having 2 to 18 carbon atoms is preferred, and an aliphatic secondary amine having 3 to 8 carbon atoms is more preferred.

  A tertiary amino group-containing polyol (a) is obtained by neutralizing part or all of the tertiary amino group of the tertiary amino group-containing polyol (a) with an acid or quaternizing with a quaternizing agent. Water dispersibility can be imparted to the cationic polyurethane resin (A) obtained by reacting with the polyisocyanate (g).

  Examples of the acid that can be used for neutralizing part or all of the tertiary amino group include formic acid, acetic acid, propionic acid, succinic acid, glutaric acid, butyric acid, lactic acid, malic acid, and citric acid. , Organic acids such as tartaric acid, malonic acid, adipic acid, organic sulfonic acids such as sulfonic acid, paratoluenesulfonic acid, methanesulfonic acid, and hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, boric acid, phosphorous acid, hydrofluoric acid Inorganic acids such as can be used. These acids may be used alone or in combination of two or more.

  Examples of the quaternizing agent that can be used for quaternizing a part or all of the tertiary amino group include dialkyl sulfates such as dimethyl sulfate and diethyl sulfate, methyl chloride, and ethyl chloride. Alkyl halides such as benzyl chloride, methyl bromide, ethyl bromide, benzyl bromide, methyl iodide, ethyl iodide, benzyl iodide, and alkyl or aryl sulfonates such as methyl methanesulfonate and methyl paratoluenesulfonate Epoxy such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, allyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, and phenyl glycidyl ether It is possible to use kind and the like. These may be used alone or in combination of two or more.

  In the present invention, the amount of the acid or quaternizing agent used for neutralization or quaternization of the tertiary amino group is not particularly limited, but excellent dispersion stability of the cationic polyurethane resin (A) used in the present invention. In order to express the properties, it is preferably in the range of 0.1 to 3 equivalents and more preferably in the range of 0.3 to 2.0 equivalents with respect to 1 equivalent of the tertiary amino group.

  When the cationic polyurethane resin (A) used in the present invention is compared with the cationic polyurethane resin obtained by the conventional method with the same cation concentration present in the resin, it has better self-water dispersibility. The resulting cationic polyurethane resin has good dispersion stability in an aqueous medium.

  As a mechanism capable of exhibiting such an effect, it is well known that urethane bonds in a polyurethane resin have a pseudo-crystal structure due to hydrogen bonds or the like, and a tertiary that exists in the side chain of the cationic polyurethane resin (A). A neutralized salt of an amino group or a quaternary amino group is, for example, compared with a neutralized salt of a tertiary amino group or a quaternary amino group existing in the main chain of the polyurethane resin skeleton as in the conventional technique. It is presumed that it is difficult to be affected by steric hindrance and has a high degree of freedom, so that it can easily form an association structure with water molecules important for water dispersion.

A reaction method of the compound (a-1) having two epoxy groups in one molecule and the secondary amine (a-2) for obtaining the tertiary amino group-containing polyol (a) will be described below.
The reaction ratio [NH group / epoxy group] of the epoxy group of the compound (a-1) having two epoxy groups in one molecule and the NH group of the secondary amine (a-2) is preferably equivalent. The ratio is in the range of 0.5 / 1 to 1.1 / 1, more preferably the equivalent ratio is in the range of 0.9 / 1 to 1/1.

  These reactions can be carried out under solvent-free conditions, but can also be carried out using an organic solvent for the purpose of facilitating the reaction control, or for the purpose of reducing the stirring load due to a decrease in viscosity or causing a uniform reaction. .

  The organic solvent may be any organic solvent that does not inhibit the reaction. For example, ketones, ethers, acetate esters, hydrocarbons, chlorinated hydrocarbons, amides, and nitriles can be used. .

  As said ketones, acetone, diethyl ketone, methyl ethyl ketone, methyl isobutyl ketone etc. can be used, for example. Examples of ethers that can be used include diethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, tetrahydrofuran, and dioxane.

  Examples of the acetates include ethyl acetate, butyl acetate, propyl acetate and the like. As hydrocarbons, n-pentane, n-hexane, cyclohexane, n-heptane, benzene, toluene, xylene and the like can be used. As chlorinated hydrocarbons, for example, carbon tetrachloride, dichloromethane, chloroform, trichloroethane and the like can be used. Examples of amides that can be used include dimethylformamide, and examples of nitriles include N-methylpyrrolidone and acetonitrile.

  Among the organic solvents described above, when an organic solvent having a low boiling point is used, it is preferable to perform a pressure reaction in a closed system in order to prevent scattering due to volatilization.

  The compound (a-1) having two epoxy groups in one molecule and the secondary amine (a-2) may be supplied together in a reaction vessel and reacted, and an epoxy group is contained in one molecule. Either one of the two compounds (a-1) and the secondary amine (a-2) may be charged into a reaction vessel and the other may be dropped.

  Since the reaction between the compound (a-1) having two epoxy groups in one molecule and the secondary amine (a-2) is highly reactive, it usually does not require a catalyst. However, when the substituent of the nitrogen atom of the secondary amine (a-2) is large and the reaction with the compound (a-1) is slowed by steric hindrance, phenol, acetic acid, water A proton donating substance typified by alcohols may be used as a catalyst.

  The reaction temperature is preferably in the range of room temperature to 160 degrees, more preferably in the range of 60 to 120 degrees. The reaction time is not particularly limited, but is usually in the range of 30 minutes to 14 hours. The end point of the reaction can be confirmed by the disappearance of the absorption peak near 842 cm −1 due to the epoxy group by infrared spectroscopy (IR method). Moreover, an amine equivalent (g / equivalent) and a hydroxyl equivalent (g / equivalent) can be calculated | required by a conventional method.

  When producing the cationic polyurethane resin (A), in addition to the tertiary amino group-containing polyol (a), various polyols (f) generally used for the synthesis of polyurethane depending on the purpose and application. Can be used.

  Among them, the polyester polyol, polyether polyol, polycarbonate polyol, polyester amide polyol, polyacetal polyol, polythioether polyol having a number average molecular weight of preferably in the range of 200 to 10,000, more preferably in the range of the number average molecular weight of 300 to 5,000. And various polyols such as polybutadiene polyol. These may be used alone or in combination of two or more.

  Among the above polyols, representative compounds are exemplified below for polyester polyols, polyether polyols, and polycarbonate polyols that are industrially easily available.

  As said polyester polyol, what is obtained by esterifying a low molecular weight polyol and polycarboxylic acid can be used.

  Examples of the low molecular weight polyol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 3-methyl-1,5. -Pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, polyethylene glycol (Number average molecular weight 300-6000 range), polypropylene glycol (number average molecular weight 300-6000 range), ethylene oxide-propylene oxide copolymer (number average molecular weight 300-6000) Circumference); bisphenol A, hydrogenated bisphenol A and alkylene oxide adducts thereof; trimethylolpropane, trimethylolethane, pentaerythritol, it can be used sorbitol.

  Examples of the polycarboxylic acid that can be used in producing the polyester polyol include succinic acid, adipic acid, azelaic acid, sebacic acid, todecanedicarboxylic acid, maleic anhydride, fumaric acid, 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, 1,2-bis (phenoxy) ethane p, p′-dicarboxylic acid, trimellitic acid, pyromellitic acid, and anhydrides or ester-forming derivatives of these polycarboxylic acids can be used.

  Moreover, as said polyester polyol, polyester obtained by ring-opening polymerization reaction of cyclic ester compounds, such as (epsilon) -caprolactone, these copolyesters, etc. can also be used.

  Further, as the polyether polyol, for example, a compound having at least two active hydrogen atoms described later is used as an initiator, and a compound such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, tetrahydrofuran, cyclohexylene, etc. What is obtained by addition-polymerizing 1 or more types can be used.

  Examples of the compound having at least two active hydrogen atoms include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and hexamethylene glycol. , Sucrose, methylene glycol, glycerin, sorbitol; actinic acid, trimellitic acid, hemimellitic acid, phosphoric acid, ethylenediamine, propylenediamine, diethylenetriamine, triisopropanolamine, pyrogallol, dihydrobenzoic acid, hydroxyphthalic acid, 1,2,3 -Propane trithiol or the like can be used.

  Examples of the polycarbonate polyol include 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, cyclohexanedimethanol, diethylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol (PTMG). And a reaction product of a dialkyl carbonate represented by dimethyl carbonate or the like and a cyclic carbonate represented by ethylene carbonate or the like.

  Among these, in order to prevent deterioration of the printed matter and maintain a stable printed matter for a long period of time, it is preferable to use a highly durable polyol as the polyol. It is preferable to introduce a structural unit derived from a polycarbonate polyol into the polyurethane resin (A).

  Examples of the polyisocyanate (g) that can be used in the production of the cationic polyurethane resin (A) used in the present invention include aqueous polyurethanes such as aromatic polyisocyanates, alicyclic polyisocyanates, and aliphatic polyisocyanates. Examples include various organic polyisocyanates used in the production of resins.

  Examples of the aromatic polyisocyanate include 1,3- and 1,4-phenylene diisocyanate, 1-methyl-2,4-phenylene diisocyanate, 1-methyl-2,6-phenylene diisocyanate, 1-ethyl-2, 4-phenylene diisocyanate, 1-isopropyl-2,4-phenylene diisocyanate, 1,3-dimethyl-2,4-phenylene diisocyanate, 1,3-dimethyl-4,6-phenylene diisocyanate, 1,4-dimethyl-2, 5-phenylene diisocyanate, 1,3-bis (isocyanatomethyl) -benzene, 1,4-bis (isocyanatomethyl) -benzene, meta-tetramethylxylylene diisocyanate, para-tetramethylxylylene diisocyanate, diethylbenzene diisocyanate Ne Diisopropylbenzene diisocyanate, 1-methyl-3,5-diethylbenzene diisocyanate, 3-methyl-1,5-diethylbenzene-2,4-diisocyanate, 1,3,5-triethylbenzene-2,4-diisocyanate, naphthalene- 1,4-diisocyanate, naphthalene-1,5-diisocyanate, 1-methyl-naphthalene-1,5-diisocyanate, naphthalene-2,6-diisocyanate, naphthalene-2,7-diisocyanate, 1,1′-dinaphthyl-2 , 2′-diisocyanate, biphenyl-2,4′-diisocyanate, biphenyl-4,4′-diisocyanate, 3,3′-dimethylbiphenyl-4,4′-diisocyanate, diphenylmethane-4,4′-diisocyanate, dipheny Methane-2,2'-diisocyanate, diphenylmethane-2,4'-diisocyanate and the like can be used.

  Examples of the alicyclic polyisocyanate and aliphatic polyisocyanate include tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, dodecamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,3-cyclopentylene diisocyanate, 1,3. -Cyclohexylene diisocyanate, 1,4-cyclohexylene diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanatomethyl) cyclohexane, lysine diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane Diisocyanate, 2,4'-dicyclohexylmethane diisocyanate, 2,2'-dicyclohexylmethane diisocyanate, 3,3'-di It can be used chill-4,4'-dicyclohexylmethane diisocyanate and trimers thereof and the like.

  1-methyl-2,4-phenylene diisocyanate, 1-methyl-2,6-phenylene diisocyanate, 1,3-bis (isocyanatomethyl) -benzene, 1 , 4-bis (isocyanatomethyl) -benzene, diphenylmethane-4,4′-diisocyanate, diphenylmethane-2,2′-diisocyanate, diphenylmethane-2,4′-diisocyanate, 1,6-hexamethylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, 2,4′-dicyclohexylmethane diisocyanate, and 2,2′-dicyclohexylmethane diisocyanate are preferred.

  In addition, in order to prevent deterioration such as light discoloration of the printed matter obtained in the same manner as described above, an alicyclic polyisocyanate and / or an aliphatic polyisocyanate generally referred to as non-yellowing type can be used as the polyisocyanate, thereby providing a cation. It is preferable to introduce a structural unit derived from an alicyclic polyisocyanate and / or an aliphatic polyisocyanate according to the porous polyurethane resin (A).

  In addition, as the polyisocyanate (g), considering the availability of raw materials, 1,6-hexamethylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, 2,4′-dicyclohexylmethane diisocyanate, Particular preference is given to using 2,2′-dicyclohexylmethane diisocyanate.

  Furthermore, it is preferable to introduce a structural unit containing a silanol group into the cationic polyurethane resin (A) for the purpose of further improving the water resistance of the obtained printed matter. When a structural unit containing a silanol group is introduced, a crosslinked structure is formed between particles made of a cationic polyurethane resin (A), which is an organic component, and an inorganic metal oxide matrix formed by a metal alkoxide (B). Is done.

  As a structural unit containing a silanol group, the structural unit represented by the following general formula [II] can be illustrated.

(In the formula [II], R ₅ is a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group, R ₆ is a halogen atom, an alkoxyl group, an acyloxy group, a phenoxy group, an iminooxy group, or an alkenyloxy group, n is 0, 1 or 2.)

  The compound used for introducing the structural unit represented by the general formula [II] into the cationic polyurethane resin (A) is preferably a compound (h) represented by the following general formula [III].

(In the formula [III], R ₅ is a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group, R ₆ is a halogen atom, an alkoxyl group, an acyloxy group, a phenoxy group, an iminooxy group, or an alkenyloxy group, and n Is 0, 1 or 2, and Y is an organic residue containing at least one active hydrogen group.)

  Examples of the compound (h) represented by the general formula [III] include γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-hydroxylethyl) aminopropyltrimethoxysilane, γ- (2 -Aminoethyl) aminopropyltriethoxysilane, γ- (2-hydroxylethyl) aminopropyltriethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldi Ethoxysilane, γ- (2-hydroxylethyl) aminopropylmethyldimethoxysilane, γ- (2-hydroxylethyl) aminopropylmethyldiethoxysilane or γ- (N, N-di-2-hydroxylethyl) aminopropyltriethoxy Silane, γ-aminopropyltrimethoxy Silane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane or γ- (N-phenyl) aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ- Examples include mercaptophenyltrimethoxysilane.

  When the cationic polyurethane resin (A) is produced, polyamine may be used as a chain extender for the purpose of designing a polyurethane resin having physical properties such as various mechanical properties and thermal properties.

  Examples of the polyamine that can be used as the chain extender include ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, isophoronediamine, and 4,4′-dicyclohexylmethane. Diamines such as diamine, 3,3′-dimethyl-4,4′-dicyclohexylmethanediamine, 1,4-cyclohexanediamine; N-hydroxymethylaminoethylamine, N-hydroxyethylaminoethylamine, N-hydroxypropylaminopropylamine Diamines containing one primary amino group and one secondary amino group such as N-ethylaminoethylamine and N-methylaminopropylamine; polyethylene such as diethylenetriamine, dipropylenetriamine and triethylenetetramine Hydrazines such as hydrazine, monomethylhydrazine, N, N′-dimethylhydrazine; dihydrazides such as succinic acid dihydrazide, adipic acid dihydrazide, glutaric acid dihydrazide, sebacic acid dihydrazide, isophthalic acid dihydrazide; , Semicarbazides such as 3-semicarbazide-propyl-carbazate, semicarbazide-3-semicarbazide methyl-3,5,5-trimethylcyclohexane, and the like can be used. In addition, water can also be used as a chain extender.

  When the cationic polyurethane resin (A) is produced, in addition to the polyamine, other chain extenders containing active hydrogen atoms are used for the purpose of adjusting physical properties such as various mechanical properties and thermal properties of the polyurethane resin. Can also be used.

  Examples of other chain extenders containing active hydrogen include ethylene glycol, diethylene recall, triethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1, Glycols such as 4-butanediol, hexamethylene glycol, saccharose, methylene glycol, glycerin, sorbitol; bisphenol A, 4,4′-dihydroxydiphenyl, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenylsulfone, Examples thereof include hydrogenated bisphenol A, phenols such as hydroquinone, and water, and these may be used alone or in combination within a range not deteriorating the storage stability of the cationic polyurethane resin aqueous dispersion of the present invention. There.

  Examples of the method for producing the cationic polyurethane resin (A) used in the present invention include the following methods. According to these methods, an aqueous dispersion in which particles made of the cationic polyurethane resin (A) are uniformly dispersed in an aqueous medium can be obtained.

[Method 1] A polyol (f), a polyisocyanate (g), a tertiary amino group-containing polyol (a), and a compound (h) are charged all at once or separately and reacted in a solvent or under no solvent. A polyurethane resin is produced, and some or all of the tertiary amino groups in the obtained polyurethane resin are neutralized with an acid and / or quaternized with a quaternizing agent, and then water is added to disperse in water. Method.

[Method 2] A polyol (f), a polyisocyanate (g), a tertiary amino group-containing polyol (a) and a compound (h) are charged all at once or in a divided manner, and reacted in a solvent or in the absence of a solvent. After producing a urethane prepolymer having an isocyanate group at the terminal, a polyurethane resin is produced by chain extension using a polyamine, and a part or all of the tertiary amino groups in the polyurethane resin are neutralized with an acid, and A method of adding water and dispersing it after quaternization with a / and quaternizing agent.

[Method 3] A polyol (f), a polyisocyanate (g), a tertiary amino group-containing polyol (a), and a compound (h) are charged all at once or divided and reacted in a solvent or in the absence of a solvent. After producing a urethane prepolymer having an isocyanate group at the terminal, neutralizing part or all of the tertiary amino group in the obtained urethane prepolymer with an acid and / or quaternizing with a quaternizing agent, A method in which water is added and dispersed in water, and then chain extension is performed using polyamine.

[Method 4] A polyol (f), a polyisocyanate (g), a tertiary amino group-containing polyol (a) and a compound (h) are batched or divided, charged, and reacted in a solvent or in the absence of a solvent. This produced a urethane prepolymer having an isocyanate group at the terminal, and part or all of the tertiary amino groups in the resulting urethane prepolymer were neutralized with an acid and / or quaternized with a quaternizing agent. Thereafter, a method of forcibly emulsifying in an aqueous medium using a machine such as a homogenizer to make it water-soluble or water-dispersed, and then chain-extending using polyamine.

[Method 5] By charging the polyol (f), the polyisocyanate (g), the tertiary amino group-containing polyol (a), the compound (h) and the polyamine all together and reacting them in a solvent or in the absence of a solvent. A polyurethane resin is produced, and some or all of the tertiary amino groups in the obtained polyurethane resin are neutralized with an acid and / or quaternized with a quaternizing agent, and then water is added to make the solution water-soluble or Method to disperse in water.

[Method 6] A polyurethane resin is produced by charging a polyol (f), a polyisocyanate (g), and a tertiary amino group-containing polyol (a) in a batch or divided and reacting them in a solvent or in the absence of a solvent. A method in which part or all of the tertiary amino groups in the obtained polyurethane resin are neutralized with an acid and / or quaternized with a quaternizing agent, and then water is added to disperse in water.

[Method 7] A polyol (f), a polyisocyanate (g), and a tertiary amino group-containing polyol (a) are charged all at once or separately, and reacted in a solvent or in the absence of a solvent to form an isocyanate group at the terminal. After producing a urethane prepolymer having a polyurethane resin, a polyurethane resin is produced by chain extension using a polyamine, and some or all of the tertiary amino groups in the obtained polyurethane resin are neutralized with an acid, and / or 4 A method in which water is added and dispersed after quaternization with a classifier.

[Method 8] A polyol (f), a polyisocyanate (g), and a tertiary amino group-containing polyol (a) are charged all at once or separately, and reacted in a solvent or in the absence of a solvent to form an isocyanate group at the terminal. The urethane prepolymer is produced, and part or all of the tertiary amino groups in the obtained urethane prepolymer are neutralized with an acid and / or quaternized with a quaternizing agent, and then water is added thereto. A method in which water is dispersed and then chain elongation is performed using polyamine.

[Method 9] A polyol (f), a polyisocyanate (g), and a tertiary amino group-containing polyol (a) are charged together or divided and charged, and reacted in a solvent or in the absence of a solvent to react with an isocyanate at the end. After producing a urethane prepolymer having a group and neutralizing a part or all of the tertiary amino group with an acid and / or quaternizing with a quaternizing agent, using a machine such as a homogenizer in an aqueous medium A method of forcibly emulsifying and dispersing in water, followed by chain elongation using polyamine.

[Method 10] A polyurethane resin is produced by charging a polyol (f), a polyisocyanate (g), a tertiary amino group-containing polyol (a) and a polyamine in a lump and reacting them in a solvent or in the absence of a solvent. A method in which part or all of the tertiary amino groups in the obtained polyurethane resin are neutralized with an acid and / or quaternized with a quaternizing agent, and then water is added to disperse in water.

  In addition, in the manufacturing method of said [Method 1]-[Method 10], you may use an emulsifier as needed.

  The emulsifier that can be used in the present invention is not particularly limited, but is basically nonionic or cationic from the viewpoint of maintaining excellent storage stability of the aqueous dispersion of the cationic polyurethane resin (A). Is preferred. For example, nonionic emulsifiers such as polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene styryl phenyl ether, polyoxyethylene sorbitol tetraoleate, polyoxyethylene / polyoxypropylene copolymer; alkylamine salts, It is preferable to use cationic emulsifiers such as alkyltrimethylammonium salts and alkyldimethylbenzylammonium salts. An anionic or amphoteric emulsifier may be used in combination as long as the mixing stability of the emulsifier to the cationic polyurethane resin aqueous dispersion is maintained.

  When the cationic polyurethane resin (A) is produced by the above-described method, a compound having a group capable of becoming a hydrophilic group (hereinafter referred to as a hydrophilic group-containing compound) is used as an aid for assisting water dispersibility of the resin. May be.

  As such a hydrophilic group-containing compound, an anionic group-containing compound, a cationic group-containing compound, an amphoteric group-containing compound, or a nonionic group-containing compound can be used, but the excellent storage stability of the cationic polyurethane resin aqueous dispersion is excellent. From the viewpoint of maintaining the properties, a nonionic group-containing compound is preferable.

  The nonionic group-containing compound includes a group having at least one active hydrogen atom in the molecule and consisting of a repeating unit of ethylene oxide, and a group consisting of a repeating unit of ethylene oxide and another repeating unit of alkylene oxide. A compound having at least one functional group selected from the group can be used.

  For example, polyoxyethylene glycol or polyoxyethylene-polyoxypropylene having a number average molecular weight of 300 to 20,000 containing at least 30% by mass of repeating units of ethylene oxide and containing at least one active hydrogen atom in the polymer Nonionic group-containing compounds such as copolymer glycols, polyoxyethylene-polyoxybutylene copolymer glycols, polyoxyethylene-polyoxyalkylene copolymer glycols or their monoalkyl ethers, or polyesters obtained by copolymerizing these Compounds such as polyether polyols can be used.

  Next, the raw material charging ratio (equivalent ratio) when producing the cationic polyurethane resin (A) will be described in detail.

  When the polyol (f), the tertiary amino group-containing polyol (a), and the polyisocyanate (g) are reacted, the equivalent ratio of the isocyanate group to the active hydrogen atom-containing group [equivalent of isocyanate group possessed by (g)] / [Equivalent hydroxyl group of (f) + Equivalent hydroxyl group of (a)] is preferably adjusted to a range of 0.9 / 1 to 1.1 / 1.

  When the cationic polyurethane resin (A) is produced, for example, when a polyamine is used as the chain extender, the equivalent ratio of isocyanate group to active hydrogen atom-containing group [equivalent of isocyanate in (g)] / [(f ) + Equivalent of hydroxyl group possessed by (a) + equivalent of hydroxyl group possessed by (a) + equivalent of amino group possessed by polyamine] is preferably adjusted in the range of 0.9 / 1 to 1.1 / 1.

  Moreover, you may manufacture the said cationic polyurethane resin (A) by making chain | strand extension reaction using a polyamine, after manufacturing a urethane prepolymer. In this case, the equivalent ratio of the isocyanate group to the active hydrogen atom-containing group [equivalent of isocyanate group possessed by (g)] / [equivalent hydroxyl group possessed by (f) + equivalent hydroxyl group possessed by (a)] It is preferable to adjust to the range of 1/1 to 3/1, and it is more preferable to adjust to the range of 1.2 / 1 to 2/1. In this case, the equivalent ratio of the amino group and excess isocyanate group of the polyamine when chain-extending with the polyamine is preferably in the range of 1.1 / 1 to 0.9 / 1.

  Further, when the polyol (f), the tertiary amino group-containing polyol (a), the compound (h), and the polyisocyanate (g) are reacted, the equivalent ratio of the isocyanate group and the active hydrogen atom-containing group [(g) Equivalents of isocyanate groups possessed by] / [equivalents of hydroxyl groups possessed by (f) + equivalents of hydroxyl groups possessed by (a) + equivalents of active hydrogen groups possessed by (h)] are 0.9 / 1 to 1.1 / It is preferable to adjust to the range of 1.

  When the cationic polyurethane resin (A) is produced, for example, when a polyamine is used as a chain extender, the equivalent ratio of the isocyanate group and the active hydrogen atom-containing group [equivalent of isocyanate group possessed by (g)] / [ (F) equivalent of hydroxyl group + equivalent of hydroxyl group of (a) + equivalent of active hydrogen group of (h) + equivalent of active hydrogen group of polyamine] is 0.9 / 1 to 1.1 / It is preferable to adjust to the range of 1.

  Moreover, you may manufacture the said cationic polyurethane resin (A) by making chain | strand extension reaction using a polyamine, after manufacturing a urethane prepolymer. In this case, the equivalent ratio of the isocyanate group to the active hydrogen atom-containing group [equivalent of isocyanate group possessed by (g)] / [equivalent hydroxyl group possessed by (f) + equivalent hydroxyl group possessed by (a) + (h) The equivalent of active hydrogen group] is preferably in the range of 1.1 / 1 to 3/1, and more preferably in the range of 1.2 / 1 to 2/1. In this case, the equivalent ratio of the amino group and excess isocyanate group of the polyamine when chain-extending with the polyamine is preferably in the range of 1.1 / 1 to 0.9 / 1.

  In such a reaction, the reaction temperature is preferably in the range of 20 to 120 ° C, more preferably in the range of 30 to 100 ° C.

  Further, the tertiary amino group-containing polyol (a) is preferably 0.005 to 1.5 with respect to the finally obtained cationic polyurethane resin (A) for the purpose of expressing excellent storage stability. The range is 5 eq / kg, more preferably 0.03 to 1.0 eq / kg, and still more preferably 0.15 to 0.5 eq / kg.

  The compound (h) is preferably in the range of 0.1 to 20% by mass, more preferably in the range of 0.5 to 10% by mass with respect to the finally obtained cationic polyurethane resin (A). It is.

The cationic polyurethane resin (A) can be produced under solvent-free conditions, but for the purpose of facilitating the reaction control, or for the purpose of reducing the stirring load due to a decrease in viscosity or causing a uniform reaction, under an organic solvent. It is also possible to manufacture with.
Examples of the organic solvent include ketones such as acetone, diethyl ketone, methyl ethyl ketone, and methyl isobutyl ketone; ethers such as diethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, tetrahydrofuran, and dioxane; ethyl acetate Acetic esters such as butyl acetate and propyl acetate; Nitriles such as acetonitrile; Hydrocarbons such as n-pentane, n-hexane, cyclohexane, n-heptane, benzene, toluene and xylene; Carbon tetrachloride, dichloromethane and chloroform Chlorinated hydrocarbons such as trichloroethane; amides such as dimethylformamide and N-methylpyrrolidone can be used.

  The cationic polyurethane resin (A) can be produced without a catalyst, but various catalysts such as stannous octylate, dibutyltin dilaurate, dibutyltin dimaleate, dibutyltin diphthalate, dibutyltin dimethoxide Tin compounds such as dibutyltin diacetylacetate and dibutyltin diversate, titanate compounds such as tetrabutyl titanate, tetraisopropyl titanate and triethanolamine titanate, other tertiary amines, quaternary ammonium salts and the like may be used.

  The organic solvent contained in the aqueous dispersion of the cationic polyurethane resin (A) obtained as described above is preferably removed, for example, by a method such as distillation under reduced pressure during or after the reaction.

  The cationic polyurethane resin (A) is preferably contained in the second ink in an amount of 1 to 30% by weight in terms of solid content, and more preferably in the range of 2 to 25% by weight. If it is less than 1% by weight, the curing of the first ink tends to be insufficient, and if it exceeds 30% by weight, the ejection stability of the second ink tends to be poor.

The second ink used in the present invention may be prepared by appropriately adding a coloring material used in the first ink, a wetting agent (drying inhibitor), a penetrating agent, or other additives. it can.
The surface tension of the second ink is preferably 20 mN / m or more and 60 mN / m or less. More preferably, it is 20 mN / m or more and 45 mN / m or less, More preferably, it is 20 mN / m or more and 40 mN / m or less. If the surface tension is less than 20 mN / m, the liquid may overflow on the nozzle surface and printing may not be performed normally. On the other hand, when it exceeds 60 mN / m, the permeability to the recording medium is lowered and the repelling occurs, so that the image reproducibility tends to be inferior.

The viscosity of the second ink is preferably 1.2 mPa · s or more and 20.0 mPa · s or less, more preferably 2.0 mPa · s or more and less than 15.0 mPa · s, and still more preferably 3.0 mPa · s or more. It is less than 12.0 mPa · s. When the viscosity is within this range, it is possible to achieve excellent dischargeability and good jetability over a long period of time.
The surface tension and viscosity of the second ink can be maintained in the above preferred ranges by adjusting the type and amount of the surfactant and water-soluble solvent to be contained.

(Ink set)
The water-based ink set for ink-jet recording of the present invention includes at least the first ink and the second ink, and the first ink and the second ink are non-absorbing so that they are in contact with each other. An image is formed on the substrate.

(Non-absorbing substrate)
As a plastic film which is a non-absorbing substrate used in the present invention, for example, those used for food packaging materials can be used, and known plastic films can be used. Specific examples include polyester films such as polyethylene terephthalate and polyethylene naphthalate, polyolefin films such as polyethylene and polypropylene, polyamide films such as nylon, polystyrene films, polyvinyl alcohol films, polyvinyl chloride films, polycarbonate films, polyacrylonitrile films, Examples include biodegradable films such as polylactic acid films. In particular, a polyester film, a polyolefin film, and a polyamide film are preferable, and polyethylene terephthalate, polypropylene, and nylon are more preferable. Moreover, the above-mentioned film coated with polyvinylidene chloride or the like for imparting a barrier property may be used, and if necessary, a film in which a deposited layer of a metal oxide such as aluminum or a metal oxide such as silica or alumina is used in combination. May be.

The plastic film may be an unstretched film, but is preferably stretched uniaxially or biaxially. Further, the surface of the film may be untreated, but those subjected to various treatments for improving adhesive properties such as corona discharge treatment, ozone treatment, low temperature plasma treatment, flame treatment, glow discharge treatment and the like are preferable.
The film thickness of the plastic film is appropriately changed according to the use. For example, in the case of a flexible packaging application, the film thickness is 10 μm to 100 μm as having flexibility, durability, and curl resistance. Preferably there is. More preferably, it is 10 micrometers-30 micrometers.

The water-based ink set for ink-jet recording according to the present invention includes not only a normal ink-jet recording apparatus but also a recording apparatus equipped with a heater for controlling ink drying or the like, or an intermediate transfer mechanism, and a recording material as an intermediate. It can also be used in a recording apparatus or the like that prints on a recording medium such as a non-absorbing substrate after printing.
Any conventionally known method can be used as the ink jet recording method. For example, a method of ejecting droplets using vibration of a piezoelectric element (a recording method using an ink jet head that forms ink droplets by mechanical deformation of an electrostrictive element) or a method of using thermal energy can be given.

  In the method of the present invention, when the first ink and the second ink are applied on the non-absorbing substrate so as to be in contact with each other, there is no particular limitation on the order of the application, and the application of the first ink The second ink may be applied later, the first ink may be applied after the second ink application, or may be applied simultaneously.

  The applied amounts of the first ink and the second ink applied to form one pixel are not necessarily equal, but are within a range of 1:10 to 10: 1 in mass ratio. Thus, it is a preferable aspect to apply ink.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not restrict | limited to the following Example at all. In addition, the part in an Example below represents a mass part.

(Example of resin production)
[Intermediate Synthesis Example 1] Synthesis of tertiary amino group-containing polyol (TAP-1) Polypropylene glycol diglycidyl ether (epoxy equivalent: 201 g) was added to a four-necked flask equipped with a thermometer, a stirring device, a reflux condenser, and a dropping device. After charging 590 parts by mass), the flask was purged with nitrogen. Next, after heating using an oil bath until the temperature in the flask reaches 70 ° C., 380 parts by mass of di-n-butylamine is added dropwise over 30 minutes using a dropping device. The reaction was allowed for 10 hours. After completion of the reaction, using an infrared spectrophotometer (FT / IR-460Plus, manufactured by JASCO Corporation), it is confirmed that the absorption peak near 842 cm ⁻¹ due to the epoxy group of the reaction product has disappeared. A tertiary amino group-containing polyol (TAP-1) (amine equivalent 339 g / equivalent, hydroxyl equivalent 339 g / equivalent) was prepared.

[Intermediate Synthesis Example 2] Synthesis of tertiary amino group-containing polyol (TAP-2) Instead of polypropylene glycol diglycidyl ether (epoxy equivalent 201 g / equivalent), polyethylene glycol diglycidyl ether (epoxy equivalent 185 g / equivalent) 543 mass A tertiary amino group-containing polyol (TAP-2) (amine equivalent 315 g / equivalent, hydroxyl equivalent 315 g / equivalent) was prepared in the same manner as in Intermediate Synthesis Example 1 except that the above components were used.

[Production Example 1] Production of cationic polyurethane resin aqueous dispersion (CUR-1) In a four-necked flask equipped with a thermometer, a stirring device, a reflux condenser, and a dropping device, "Nipporan 980R" [Nippon Polyurethane Industry Co., Ltd.] 705 parts by mass of polycarbonate polyol obtained by reacting 1,6-hexanediol and dimethyl carbonate, hydroxyl equivalent 986 g / equivalent], neopentyl glycol, 1,4-butanediol, terephthalic acid and adipic acid 352 parts by mass of polyester (hydroxyl equivalent 951 g / equivalent) obtained by the reaction was added, and dehydration was performed at 120 to 130 ° C. under a reduced pressure of 0.095 MPa.

  After dehydration, the mixture was cooled to 70 ° C., 666 parts by mass of ethyl acetate was added, and the mixture was sufficiently stirred and mixed while cooling to 50 ° C. After stirring and mixing, 280 parts by mass of 4,4′-dicyclohexylmethane diisocyanate (4,4-H-MDI) and 0.3 part by mass of tin octylate (II) were added and reacted at 70 ° C. for 2 hours.

  After completion of the reaction, 84 parts by mass of the tertiary amino group-containing polyol (TAP-1) obtained in Intermediate Synthesis Example 1 was added, reacted for 4 hours, cooled to 55 ° C., and “aminosilane A1100” [Japan Unicur Co., Ltd., [gamma-aminopropyltriethoxysilane] 47 parts by mass was added and reacted for 1 hour to prepare a urethane prepolymer solution having a terminal isocyanate group. Next, 15 parts by mass of hydrazine hydrate was added to the urethane prepolymer solution, and a chain extension reaction was performed for 1 hour.

Next, 1954 parts by mass of ethyl acetate and 16 parts by mass of acetic acid were added and held at 55 ° C. for 1 hour, then cooled to 40 ° C., and 3300 parts by mass of ion-exchanged water was added to prepare an aqueous dispersion. did. This aqueous dispersion was distilled under reduced pressure to obtain a cationic polyurethane resin aqueous dispersion (CUR-1) having a nonvolatile content of 35% by mass and a pH of 4.1.
The pH is a value measured in a 25 ° C. environment using a PH meter (MM-60R manufactured by Toa DKK Co., Ltd.). Hereinafter, the pH was measured by the same method.

[Production Example 2] Production of cationic polyurethane resin aqueous dispersion (CUR-2) The tertiary amino group-containing polyol (TAP-2) prepared in Synthesis Example 2 instead of the tertiary amino group-containing polyol (TAP-1) ) Is used in the same manner as in Production Example 1, except that 186 parts by mass of tolylene diisocyanate is used instead of 4,4′-dicyclohexylmethane diisocyanate. % Aqueous solution of cationic polyurethane resin (CUR-2) having a pH of 4.4 was obtained.

[Production Example 3] Production of cationic polyurethane resin aqueous dispersion (CUR-3) A non-volatile content of 35 masses in the same manner as in Production Example 1 except that 31 parts by mass of dimethyl sulfate was used instead of acetic acid. A cationic polyurethane resin aqueous dispersion (CUR-3) having a pH of 5.7% was obtained.

[Production Example 4] Production of cationic polyurethane resin aqueous dispersion (CUR-4) A non-volatile content of 35 masses in the same manner as in Production Example 2 except that 31 parts by mass of dimethyl sulfate was used instead of acetic acid. A cationic polyurethane resin aqueous dispersion (CUR-4) having a pH of 5.6% was obtained.

[Production Example 5] Production of cationic polyurethane resin aqueous dispersion (CUR-5) In a four-necked flask equipped with a thermometer, a stirrer, a reflux condenser and a dropping device, "Nipporan 980R" [Nippon Polyurethane Industry Co., Ltd.] Manufactured, polycarbonate polyol obtained by reacting 1,6-hexanediol and dimethyl carbonate, hydroxyl equivalent 986 g / equivalent] 705 parts by mass, neopentyl glycol, 1,4-butanediol, terephthalic acid and adipic acid The resulting polyester (hydroxyl equivalent 951 g / equivalent) was added in an amount of 352 parts by mass, and dehydration was performed at 120 to 130 ° C. at a reduced pressure of 0.095 MPa.

  Next, after cooling to 70 ° C., 295 parts by mass of polypropylene glycol (hydroxyl equivalent: 500 g / equivalent) having a molecular weight of 1000 and 666 parts by mass of ethyl acetate were added, cooled to 50 ° C., sufficiently stirred and mixed, 280 parts by mass of 4′-dicyclohexylmethane diisocyanate and 0.3 part by mass of stannous octylate were added and reacted at 70 ° C. for 2 hours.

  After completion of the reaction, 84 parts by mass of the tertiary amino group-containing polyol (TAP-1) obtained in Intermediate Synthesis Example 1 was added, reacted for 4 hours, cooled to 55 ° C., and “Aminosilane A1100” [Japan Unicar Co., Ltd., γ-aminopropyltriethoxysilane] 47 parts by mass was added and reacted for 1 hour. After completion of the reaction, using an infrared spectrophotometer (FT / IR-460Plus, manufactured by JASCO Corporation), it is confirmed that the absorption peak near 2280 cm-1 due to the isocyanate group of the reaction product has disappeared. did.

  Next, 1954 parts by mass of ethyl acetate and 16 parts by mass of acetic acid were added and held at 55 ° C. for 1 hour, then cooled to 40 ° C., and 3300 parts by mass of ion-exchanged water was added to prepare an aqueous dispersion. . The obtained aqueous dispersion was distilled under reduced pressure to obtain a cationic polyurethane resin aqueous dispersion (CUR-5) having a non-volatile content of 35% by mass and a pH of 4.5.

[Production Example 6] Production of cationic polyurethane resin aqueous dispersion (CUR-6) Instead of tertiary amino group-containing polyol (TAP-1), 78 parts by mass of tertiary amino group-containing polyol (TAP-2) is used. And 186 parts by mass of tolylene diisocyanate instead of 4,4′-dicyclohexylmethane diisocyanate, the same method as in Production Example 5, with a non-volatile content of 35% by mass and a pH of 4 A cationic polyurethane resin aqueous dispersion (CUR-6) was obtained.

[Production Example 7] Production of cationic polyurethane resin aqueous dispersion (CUR-7) Production Example except that "aminosilane A1100" is not used and the amount of hydrazine hydrate used is changed to 20 parts by mass. In the same manner as in No. 1, a cationic polyurethane resin aqueous dispersion (CUR-7) having a nonvolatile content of 35% by mass and a pH of 4.5 was obtained.

[Production Example 8] Production of cationic polyurethane resin aqueous dispersion (CUR-8) "Nipporan 980R" [manufactured by Nippon Polyurethane Industry Co., Ltd., polycarbonate polyol obtained by reacting 1,6-hexanediol and dimethyl carbonate, Hydroxyl equivalent 986 g / equivalent. ], And the polyester obtained by reacting neopentyl glycol, 1,4-butanediol, terephthalic acid and adipic acid (hydroxyl equivalent g / equivalent 951) is not used. "Aminosilane A1100" (manufactured by Nihon Unicar Co., Ltd., γ-aminopropyltriethoxysilane), changing the amount of hydrazine hydrate to 20 parts by mass, and dimethyl sulfate instead of acetic acid A cationic polyurethane resin aqueous dispersion (CUR-8) having a nonvolatile content of 35% by mass and a pH of 5.7 was obtained in the same manner as in Example 1 except that 31 parts by mass of was used.

[Comparative Production Example 1] (Production of aqueous polyurethane resin (HUR-1))
1000 parts of polycarbonate polyol “Nipporan N981” (average molecular weight = 1000) manufactured by Nippon Polyurethane Industry Co., Ltd. was dehydrated at 100 ° C. under reduced pressure. Thereafter, the mixture was cooled to 80 ° C., 1000 parts of ethyl acetate was added and sufficiently stirred to dissolve.
Next, 100 parts of 2,2′-dimethylolpropionic acid was added, and then 400 parts of tolylene diisocyanate was added and reacted at 75 ° C. for 5 hours to obtain a polyurethane prepolymer.
After confirming that the isocyanate value became 1.80 to 1.90%, the mixture was cooled to 40 ° C., neutralized by adding 75 parts of triethylamine, and then dissolved by adding 7000 parts of water. Subsequently, 36 parts of 80% hydrazine hydrazine was added as a chain extender to carry out a chain extension reaction.
Ethyl acetate was removed from the obtained translucent reaction product under reduced pressure at 30 to 60 ° C., and water was added to adjust the concentration. An aqueous polyurethane resin (HUR-1) was obtained.

[Comparative Production Example 2] (Production of aqueous polyurethane resin (HUR-2))
In place of polycarbonate polyol “Nipporan N981” manufactured by Nippon Polyurethane Industry Co., Ltd. in Comparative Production Example 1, polytetramethylene ether glycol “PTMG-1000” (average molecular weight = 1000) manufactured by Mitsubishi Chemical Co., Ltd. was used. The aqueous polyurethane resin (HUR-2), which is a stable translucent aqueous dispersion having a non-volatile content of 20% and Tg-50 ° C., was obtained except for the above.

(Cyan ink preparation example)
20 parts of cyan pigment “FANTOGENBLUEFSJ-SD” manufactured by DIC Corporation, 30 parts of “Disperbyk-190” manufactured by Big Chemie Japan Co., Ltd. as a pigment dispersant, 5 parts of isopropyl alcohol, and 45 parts of pure water were mixed with stirring. . Next, after the kneaded meat was dispersed using a bead mill, coarse particles were removed by a centrifugal separator, and pure water was added to obtain a cyan pigment dispersion prepared to have a pigment concentration of 15% by mass.
Using the cyan aqueous pigment dispersion, a mixture obtained according to the composition of Table 1 or Table 5 was filtered through a 0.5 μm filter to obtain cyan inks (C-1) to (C-6) and (HC−). 7) was obtained.

(Yellow ink preparation example)
20 parts of a yellow pigment “NOVOPERMYELLOW4G-01” manufactured by Clariant Japan Co., Ltd., 30 parts of “Disperbyk-190” manufactured by Big Chemie Japan Co., Ltd. as a pigment dispersant, 5 parts of isopropyl alcohol, and 45 parts of pure water are mixed with stirring. did. Next, after the kneaded meat was dispersed using a bead mill, coarse particles were removed by a centrifugal separator, and pure water was added to obtain a yellow pigment dispersion prepared to have a pigment concentration of 15% by mass.
Using the yellow aqueous pigment dispersion, the mixture obtained according to the composition of Table 2 was filtered through a 0.5 μm filter to obtain yellow inks (Y-1) to (Y-6).

(Example of magenta ink preparation)
20 parts of magenta pigment “Irgazin Magenta 2012” manufactured by BASF Corporation, 30 parts of “Disperbyk-190” manufactured by Big Chemie Japan Co., Ltd. as a pigment dispersant, 5 parts of isopropyl alcohol, and 45 parts of pure water were mixed with stirring. Next, after the kneaded meat was dispersed using a bead mill, coarse particles were removed by a centrifugal separator, and pure water was added to obtain a magenta pigment dispersion prepared to have a pigment concentration of 15% by mass.
Using the magenta pigment dispersion, a mixture obtained according to the composition of Table 3 or Table 5 was filtered through a 0.5 μm filter to obtain magenta inks (M-1) to (M-6), (HM-7). ) To (HM-8) were obtained.

(Black ink preparation example)
20 parts of black pigment “Carbon Black # 960” manufactured by Mitsubishi Chemical Corporation, 30 parts of “Disperbyk-190” manufactured by Big Chemie Japan Co., Ltd., 5 parts of isopropyl alcohol and 45 parts of pure water as a pigment dispersant are stirred. Mixed. Next, after kneading with a bead mill, coarse particles were removed by a centrifugal separator, and pure water was added to obtain a black pigment dispersion prepared to have a pigment concentration of 15% by mass.
Using the black pigment dispersion, the mixture obtained according to the composition of Table 4 was filtered through a 0.5 μm filter to obtain black inks (K-1) to (K-6).

(Second ink adjustment example)
According to the composition of Tables 6 to 9, the second ink was prepared.

Details of the substances described in Tables 1 to 9 are as follows. Unless otherwise indicated, the reagents were used as they were.
Aptolock BW-5550 (trade name): olefin emulsion (Mitsubishi Chemical Corporation, pH: 8, acid value: 18 mg KOH / g, solid content 30%)
Hardren NA-3002 (trade name): Olefin emulsion (manufactured by Toyobo Co., Ltd., pH: 8, acid value: 33 mg KOH / g, solid content 30%)
Vylonal MD-2000: polyester emulsion (manufactured by Toyobo Co., Ltd., pH: 6, hydroxyl value: 6 mg KOH / g, solid content 40%)
Surfynol 440 (trade name): Surfactant manufactured by Air Products Japan Co., Ltd. Polyallylamine PAA-01 (trade name): manufactured by Nittobou Medical Co., Ltd., active ingredient concentration 15%, average molecular weight 1,600 (catalog description) value))
Polyallylamine PAA-1112 (trade name): manufactured by Nittobo Medical Co., Ltd., active ingredient concentration 15%, average molecular weight 1,000 (value indicated in catalog))
Stearyl trimethyl ammonium chloride (reagent, Tokyo Chemical Industry)

* 1 Formula weight.
* 2 Value described in the catalog.

(Measurement method of acid value)
The acid value was measured by a method based on JIS K0070. In the present invention, the following solvents were used as measurement solvents.
10 g of the resin obtained by drying and solidifying the resin aqueous solution is weighed into a 300 ml Erlenmeyer flask, and about 50 ml of a mixed solvent of ethanol: benzene = 1: 2 is added to dissolve the resin. Subsequently, using a phenolphthalein indicator, titration was performed with a 0.1 mol / L potassium hydroxide ethanol solution that had been standardized in advance, and the acid value ( mgKOH / g) is determined.

  In the formula, A is the acid value of the resin (mgKOH / g), B is the amount of 0.1 mol / L potassium hydroxide ethanol solution used for titration (ml), and f is the 0.1 mol / liter potassium hydroxide ethanol solution. The factor, S is the mass (g) of the resin, and 5.611 is a value (56.11 / 10) of 1/10 of the formula weight of potassium hydroxide.

  For resins that do not dissolve in about 50 ml of a mixed solvent of ethanol: benzene = 1: 2, select either 50 ml of ethanol or about 50 ml of a mixed solvent of ethanol / pure water = 1: 1. The others are titrated by the same operation.

(Measurement method of hydroxyl value)
The hydroxyl value was measured by a method based on JIS K0070. In this invention, the solvent shown below was used as a solvent for a measurement.
3 g of resin obtained by drying and solidifying the above resin aqueous solution is weighed into a 100 ml Erlenmeyer flask, 10.0 ml of acetic anhydride solution is added and stirred for 15 minutes. Add 2 ml of water and 10.0 ml of pyridine + water (3 + 1) and stir for 5 minutes. 10.0 ml of pyridine was added, titration was performed with a 0.5 mol / l potassium hydroxide ethanol aqueous solution, and the hydroxyl value (mgKOH / g) was determined according to the calculation formula (2).

  In the formula, A is the hydroxyl value of the resin (mgKOH / g), B is the blank value, C is the amount of 0.5 mol / l potassium hydroxide ethanol aqueous solution used for titration (ml), f is the factor of the titrant, D Is a concentration conversion factor, E is a unit conversion factor, and S is a sampled amount.

(Measurement method of Tg (glass transition temperature))
The DSC measurement was performed at a heating rate of 5 ° C./min according to JIS7122 using a DuPont thermal analyzer DSC10.

(Measurement method of weight average molecular weight (Mw))
Mw was determined by GPC measurement under the following conditions.
[GPC measurement conditions]
Measuring device: “HLC-8220GPC” manufactured by Tosoh Corporation
Column: Guard column “SuperHZ-L” manufactured by Tosoh Corporation (inner diameter 4.6 mm × 2 cm)
+ Tosoh Corporation “TSKgelSuperHZ4000” (inner diameter 4.6 mm × 15 cm)
+ "TSKgelSuperHZ3000" manufactured by Tosoh Corporation (inner diameter 4.6 mm x 15 cm)
+ Tosoh Corporation “TSKgelSuperHZ2000” (inner diameter 4.6 mm × 15 cm)
+ "TSKgelSuperHZ1000" manufactured by Tosoh Corporation (inner diameter 4.6 mm x 15 cm)
Measurement conditions: Column temperature 40 ° C
Flow rate 0.35 ml / min Sample: A resin aqueous solution was dried and solidified, and a 0.5 mass% tetrahydrofuran (THF) solution in terms of resin solid content was filtered through a microfilter (10 μl).
Calibration curve: Monodisperse standard polystyrene STK standard polystyrene (manufactured by Tosoh Corporation) A calibration curve with samples having a molecular weight of 4000000 to 250 was used.

(Examples 1 to 126, Comparative Examples 1 to 4)
Each ink set was loaded into an ink jet recording apparatus (EB-100 manufactured by Konica Minolta Co., Ltd.) having 256 nozzles × 2 rows of piezo ink jet nozzles, and an OPP film (FOR # manufactured by Futamura Chemical Co., Ltd.) was used as a recording material. 20 and a film thickness of 20 μm). The droplet size was about 42 pl so that it could be ejected at a resolution of 360 × 360 dpi (dpi is the number of dots per 2.54 cm) and was driven at a driving frequency of 2 kHz. While preheating with a heater so that the surface of the film was about 60 ° C., printing was performed according to the following ink application sequence, followed by drying (80 ° C./60 seconds).

(Ink application order)
Type A: The second ink is applied after the first ink is applied.
Type B: The first ink is applied after the second ink is applied.
Type C: First ink and second ink are applied simultaneously.

(PH measurement method)
Measurement was performed using MM-60R (manufactured by Toa DKK Co., Ltd.) (ink temperature 25 ° C.).

(Evaluation method)
The following physical properties (1) to (5) were evaluated in a constant temperature and humidity chamber (room temperature: 25 ° C., humidity: 50%) for the ejection properties and the obtained printing.

(1) Dischargeability The nozzle clogging after continuous 12 sheets printing was evaluated.
○: Ink does not adhere around the nozzle, and the nozzle is not clogged.
Δ: Ink adheres around the nozzle, but the nozzle is not clogged.
×: Nozzle clogged.

(2) Breathability (bleed)
○: Ink does not bleed at the boundary between halftone dots and solid portions.
Δ: There is a slight blur at the boundary between halftone dots and solid portions.
X: The dot of a halftone dot and a solid part spread.

(3) Repelling ◯: Ink does not repel at halftone dots and solid portions.
Δ: Ink is slightly repelled at halftone dots and solid portions.
X: Ink repels at halftone dots and solid areas.

(4) Solid part reproducibility: The ink is reproduced without density unevenness in the solid image printing part.
(Triangle | delta): The density nonuniformity of a solid image printing part is less than 20% with respect to a printing part.
X: Density unevenness of the solid image printing part is 20% or more with respect to the printing part.
The evaluation results are shown in Tables 10 to 34.

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): hydroxy group and / or carboxyl group-containing resin (solid content) / cationic polyurethane resin (A) (solid content)

Ink application order type A: Application of the second ink after application of the first ink Type B: Application of the first ink after application of the second ink Type C: Application of the first ink and the second ink simultaneously Ink mixing ratio (mass ratio): resin having no hydroxy group and / or carboxyl group (solid content) / cationic polyurethane resin (A) (solid content)

  As a result, the ink sets obtained in Examples 1 to 182 all had good bleeding, repelling, and solid portion reproducibility. On the other hand, Comparative Examples 1 to 4 are examples in which a resin having no hydroxy group and carboxyl group was used as the binder resin in the first ink. Comparative Examples 5 to 7 are examples in which the cationic polyurethane resin (A) is not used as the second ink, but a desired effect was not obtained.

Claims (9)

An ink set for ink jet recording using at least two kinds of inks, wherein the first ink contains a color material, a resin having a hydroxy group and / or a carboxyl group, a water-soluble solvent and / or water,
The second ink has the following general formula [I]

[In Formula (I), R ₁ is an alkylene chain which may contain an aliphatic cyclic structure, a residue of a dihydric phenol, or a polyoxyalkylene chain, and R ₂ and R ₃ are independent of each other. An alkyl group which may contain an aliphatic cyclic structure, R ₄ is a hydrogen atom or a residue of a quaternizing agent introduced by a quaternization reaction, X ⁻ is an anionic counter ion is there. ]
A water-based ink set for ink-jet recording, comprising a cationic polyurethane resin (A) containing a structural unit represented by formula (I), a water-soluble solvent and / or water. The aqueous ink set for inkjet recording according to claim 1, wherein the cationic polyurethane resin (A) is a resin having a structural unit derived from an alicyclic polyisocyanate and / or an aliphatic polyisocyanate. The cationic polyurethane resin (A) is further represented by the following general formula (II)

[In the formula (II), R ₅ is a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, R ₆ is a halogen atom, an alkoxy group, an acyloxy group, a phenoxy group, an iminooxy group or an alkenyloxy group, and n is 0, 1 or 2. ]
The water-based ink set for ink-jet recording according to claim 1, comprising a structural unit represented by: The cationic polyurethane resin (A) is represented by the following general formula [III]

Wherein R ₅ is a monovalent organic residue selected from the group consisting of a hydrogen atom, an alkyl group, an aryl group and an aralkyl group, and R ₆ is a halogen atom, an alkoxyl group, an acyloxy group, a phenoxy group, an iminooxy group or An alkenyloxy group, n is 0, 1 or 2, and Y is an organic group containing at least one active hydrogen group.)
The water-based ink set for inkjet recording according to any one of claims 1 to 3, which is a resin having a structural unit obtained by reacting a compound represented by formula (I) and an isocyanate compound. The ink set for water-based inkjet recording according to any one of claims 1 to 4, wherein the coloring material is a pigment, and the resin having the hydroxy group and / or carboxyl group is dispersed in a water-soluble solvent and / or water. The resin having a hydroxy group and / or a carboxyl group is a resin emulsion of a polyolefin resin, a polyester resin, a polyester urethane resin, an acrylic resin, a vinyl chloride resin, a vinyl acetate resin, or an epoxy resin. An ink set for water-based inkjet recording as described in 1. The resin having the hydroxy group and / or carboxyl group is a polyolefin resin having a weight average molecular weight of 10,000 to 1,000,000 and an acid value of 1 to 200 mgKOH / g. The ink set for water-based inkjet recording in any one. The ink set for water-based inkjet recording according to claim 7, wherein the polyolefin resin is a polyolefin resin having a polyether polymer chain. The water-based ink set for inkjet recording according to any one of claims 1 to 8, which prints on a non-absorbent substrate.