JPH11100528A - Active energy ray curable water-borne composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a compsn. excellent in storing stability as well as surface smoothness and paintability of a coating film by blending a water-dispersed nongel compsn. having a salt group and an active energy ray curable unsatd. group in the polyurethane resin structure with water-dispersed polyurethane microgel particles. SOLUTION: A compsn. having an active energy ray curable unsatd. group which does not react at 50 deg.C or below is usually employed. The nongel compsn. and the gel particles are blended usually at the ratio of 100/5 to 20/100 (wt. ratio). The nongel compd. is obtd. by reacting a polyisocyanate compd. having more than one functional group, a polyol having more than one functional group on an average, a compd. having an active energy ray curable unsatd. double bond group and a hydroxy group and a compd. having a salt group. The gel particles are obtd. by reacting a water-dispersible polyurethane resin structure having an isocyanate group and a salt group with a crosslinking agent. This compsn. is useful as a vehicle for paint, ink, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to paints for wooden building materials, coating agents for decorative paper for building materials, glossy varnishes for paper, aluminum, iron,
Preservation stability, printing or coating suitability, useful for metal plates such as tinplate and galvanized sheet, paints for metal materials, packaging materials, gravure inks such as cardboard, flexographic inks, etc.
The present invention relates to a water-dispersible active energy ray-curable composition having excellent adhesion and chemical resistance, low odor and low skin toxicity.

[0002]

2. Description of the Related Art Paints for wood-based building materials, coating materials for decorative paper for building materials, glossy varnishes for paper, metal plates such as aluminum, iron, tinplate, galvanized sheet, paints for metal materials, cardboard, various plastic films, etc. Active energy ray curing is applied as a curing method in the fields of paints, coatings, coatings used as inks, coating agents, inks, and the like.However, in practical use, it is necessary to go through steps such as painting and printing. In order to obtain a coating viscosity suitable for the process, it is necessary to dilute with a solvent or a monomer. Solvent-based paints, coatings, and inks that use solvents have problems in safety and health and work environments, and paints, coatings, and inks, which are said to be solvent-free, have the same problems as monomer skin toxicity and odor. There is a problem in health and safety. In addition, there is a drawback in that the polymer raw material cannot be used due to the limitation of the coating viscosity, and thus the chemical and physical performance of the coating film cannot be improved.

[0003] Water-soluble active energy ray-curable paints,
Coatings and inks have no problem with regard to such safety and health and working environment, and polymer materials can be applied. Aqueous vehicles are roughly divided into three types: emulsion type, cross-linked dispersion type (microgel), and water-soluble type (non-gel dispersion type). The former two have poor resolubility after the solvent evaporates, and paint Although the surface may be skinned or the coating machine may be difficult to clean, the water-soluble type (non-gel dispersion type) has good resolubility, and the coating machine can be washed with water. Therefore, the water-soluble type is preferred. However, inks and paints made of a water-soluble vehicle have the disadvantage of foaming during coating, and it is necessary to use an antifoaming agent. And the like, and a defect of the coating film in which the smoothness of the coating film is lost occurs.

A high-molecular weight aqueous polyurethane compound obtained by chain-extending or crosslinking a non-gel active energy ray-curable polyurethane composition dispersed in water and a isocyanate group-terminated polyurethane resin skeleton with a crosslinking agent having an active hydrogen atom; Alternatively, it has been found that the addition of a microgel (hereinafter referred to as an aqueous polyurethane microgel in the present invention) eliminates the above-mentioned defects of the coating film. However, if it is kept at room temperature for 1 to 2 weeks and at 40 ° C., it gels in a few days, which causes a new problem of storage stability. The reason is that a high molecular weight aqueous polyurethane composition or a polyurethane resin skeleton having an isocyanate group, which is a precursor of a microgel, and a crosslinking agent having an active hydrogen atom, or an active hydrogen atom such as an amino group formed by reacting with water. Alternatively, a crosslinking reaction occurs due to a Michael addition reaction between an unreacted active hydrogen atom and an active energy ray-curable double bond such as an acryloyl group of a non-gel active energy ray-curable polyurethane compound to increase the molecular weight. That's why.

[0005] If the active hydrogen atoms in the aqueous polyurethane microgel mixed with the non-gel active energy ray-curable polyurethane composition dispersed in water are reduced to zero, no Michael addition reaction takes place. Even if it reacts with an active hydrogen atom, the reaction is carried out in water, so that the isocyanate group becomes an amino group by the reaction with water, and an unreacted active hydrogen atom remains by an equivalent amount. Therefore, it is practically impossible to make active hydrogen atoms zero.

[0006]

In a paint, a coating or an ink containing an aqueous active energy ray-curable composition, storage stability is good, re-dissolving property is good, and there is no defect on a painted surface or a printed surface. An object of the present invention is to obtain an active energy ray-curable aqueous composition for obtaining a coated or printed material having high smoothness.

[0007]

Means for Solving the Problems As a result of research conducted by the present inventors, a non-gel active energy ray having an active energy ray-curable double bond in a molecule which does not cause a Michael addition reaction at 50 ° C. or less is obtained. If it is a curable polyurethane composition, even if it is a composition obtained by mixing an aqueous polyurethane microgel containing active hydrogen atoms, it does not gel, so it has excellent storage stability, and also has excellent coating smoothness and coatability. The inventors have found that an excellent active energy ray-curable aqueous composition of the present invention can be obtained, and have reached the present invention.

That is, a vehicle prepared by mixing a water-dispersed non-gel active energy ray-curable polyurethane composition of the present invention with an aqueous polyurethane microgel obtained by chain extension using an amine or water is used. By using it, it is possible to prepare paints and inks having good paintability or printability with no defects on the surface of the coating film and good printability and good storage stability, and it has become possible to solve the above problems.

That is, the active energy ray-curable aqueous composition according to the present invention has a non-gel active energy having a salt group and an active energy ray-curable unsaturated group in the molecule of the polyurethane resin skeleton dispersed in water. An active energy ray-curable aqueous composition comprising a ray-curable polyurethane composition and polyurethane microgel particles dispersed in water.

Further, the active energy ray-curable aqueous composition according to the present invention is characterized in that the unsaturated group of the non-gel active energy ray-curable polyurethane composition has a cross-linking agent having an active hydrogen atom at 50 ° C. or lower. The active energy ray-curable aqueous composition is an active energy ray-curable unsaturated group that does not react.

Further, the active energy ray-curable aqueous composition according to the present invention has a structure in which the polyurethane microgel particles have a structure in which a polyurethane resin skeleton is chain-extended or cross-linked between the skeletons via a urethane bond or a urea bond. An active energy ray-curable aqueous composition, which is a gel-like film-forming polyurethane resin particle comprising a water dispersion having a salt group.

Further, in the active energy ray-curable aqueous composition according to the present invention, the polyurethane resin skeleton is selected from a polyester urethane resin skeleton, a polyether urethane resin skeleton, a polyether polyester urethane resin skeleton, and a polycarbonate polyurethane resin skeleton. An active energy ray-curable composition which is at least one kind of resin skeleton.

Further, in the active energy ray-curable aqueous composition according to the present invention, the polyurethane resin skeleton has an isocyanate group and the crosslinked structure has a reaction between the isocyanate group and a crosslinking agent having an active hydrogen atom. An active energy ray-curable aqueous composition having a crosslinked structure formed by

Further, in the active energy ray-curable aqueous composition according to the present invention, the weight ratio of the non-gel active energy ray-curable polyurethane composition to the polyurethane microgel particles is preferably 100/5 to 20/100. Is 10
An active energy ray-curable aqueous composition in the range of 0/10 to 50/100.

Further, the active energy ray-curable aqueous composition according to the present invention is an active energy ray-curable polyurethane composition of the non-gel active energy ray-curable polyurethane composition which does not react with a crosslinking agent having an active hydrogen atom at 50 ° C. or lower. The active energy ray-curable unsaturated group is a methacryloyl group, or an unsaturated group introduced using an unsaturated dibasic acid having a double bond at the α and β positions, and an unsaturated group of a vinyl ether compound. It is an aqueous composition.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The active energy ray-curable aqueous composition of the present invention does not cause a Michael addition reaction at 50 ° C. or less with a salt group in the molecule of the polyurethane resin skeleton dispersed in water. The weight of the non-gel active energy ray-curable polyurethane composition and the aqueous polyurethane microgel particles, comprising a non-gel active energy ray-curable polyurethane composition having an unsaturated group and a polyurethane microgel dispersed in water. The ratio is 100/5
~ 20/100, preferably 100/10 ~ 50/1
It is obtained by mixing to be in the range of 00.

The non-gel active energy ray-curable polyurethane composition comprises a polyisocyanate compound having two or more functional groups (A-1), a polyol having two or more functional groups on average (A-2), and an active energy It is obtained by reacting a compound (A-3) having a line-curable unsaturated double bond and a hydroxyl group with a compound (A-4) having a salt group.

As a typical specific synthetic method, a polyisocyanate compound (A-1) having two or more functional groups, a polyol (A-2) having two or more functional groups on average, and a compound having a salt group (A-1) -4) and an isocyanate group-terminated urethane prepolymer obtained by reacting them with an isocyanate group excess, and a hydroxyl group 1 to 3 in the molecule.
Two hydroxymethacrylates (A-3) having 1 to 5 active energy ray-curable double bonds are reacted.
These reactions can be carried out at 20 to 80 ° C. by adding a solvent which does not react with isocyanate, and known polymerization inhibitors and reaction catalysts can be arbitrarily added in appropriate amounts. After the completion of the reaction, the salt group of the organic solvent solution is neutralized at 30 to 50 ° C., water is added at 5 to 40 ° C., and the reaction solvent is concentrated under reduced pressure at 50 to 60 ° C. by distillation under reduced pressure. The active energy ray-curable polyurethane composition is obtained.

In the above synthesis method, the average number of functional groups is 2
When a polyol having an average number of functional groups having two or more functional groups having a methacryloyl group in a molecule is used as one of the components of the polyol (A-2) having a functional or higher functionality, a non-gel state having an active energy ray-curable double bond in the molecular side chain The active energy ray-curable polyurethane composition is obtained. In the case of the non-gel active energy ray-curable polyurethane composition, the concentration of the unsaturated group is adjusted to be 1.5 to 4.5 equivalents / kg, more preferably 1.7 to 3.0 equivalents / kg. You.

Non-gel active energy ray-curable compositions comprising an unsaturated polyester polyurethane resin skeleton containing an unsaturated polyester polyol having a double bond at the α and β positions as the polyol component (A-2) are also α and β. Group equivalents of an unsaturated polyester introduced using an unsaturated dibasic acid having a double bond at the 1-position and the unsaturated group equivalent of the compound (A-3) having an active energy ray-curable unsaturated double bond and a hydroxyl group. It is prepared so that the sum with the saturated group becomes 1.5 to 4.5 equivalents / g, more preferably 1.7 to 3.0 equivalents / kg.

When the unsaturated polyester polyol having a double bond at the α and β positions is used as the polyol component (A-2), the compound having an active energy ray-curable unsaturated double bond and a hydroxyl group (A- 3) As hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, 4-hydroxycyclohexyl vinyl ether,
It is particularly preferable to use a hydroxy vinyl ether such as cyclohexane dimethanol monovinyl ether because of its high alternating copolymerizability. Polyurethane resin obtained as a polyol component (A-2) using an unsaturated polyester polyol having a double bond at the α and β positions introduced using an unsaturated dibasic acid having a double bond at the α and β positions Skeleton (A)
The equivalent ratio of the unsaturated group of the vinyl ether to 1 equivalent of the unsaturated group is preferably 0.2 to 5, and more preferably 0.5 to 2.

The above-mentioned aqueous polyurethane microgel particles dispersed in water are formed by crosslinking a water-dispersible polyurethane resin skeleton (A) having an isocyanate group and a salt group and a urethane bond or a urea bond between the skeletons. It is obtained by reacting with a crosslinking agent (B).

As a typical method for producing the aqueous polyurethane microgel particles dispersed in water, a water-dispersible polyurethane resin skeleton having an isocyanate group and a salt group, which has been previously reacted in an organic solvent, may be used. A) preparing a solution which is neutralized, ionized and dispersed in water, of the salt groups of A)
Crosslinking agent (B) dissolved in water or organic solvent in the solution
Is added to obtain polyurethane microgel particles dispersed in water containing an organic solvent, and the solvent is removed if necessary.

As a reverse procedure, an isocyanate group previously reacted in an organic solvent is mixed with an active energy ray in a solution in which a crosslinking agent (B) is dissolved in water or a mixture of water and an organic solvent. By neutralizing and then dispersing a salt group of the polyurethane resin skeleton (A) having a curable unsaturated double bond and a salt group, polyurethane microgel particles dispersed in water containing an organic solvent are obtained, Then, the solvent can be removed if necessary.

The above-mentioned polyurethane resin skeleton (A)
Is a difunctional or higher polyisocyanate compound (A-1)
And a polyol having two or more average functional groups (A-2)
And a compound (A-4) having a salt group to obtain a polyurethane resin skeleton (A) having a terminal isocyanate group.

(A-1), (A-2) and (A-4)
Is such that the isocyanate group content after the reaction is 1.0
It can be determined to be 〜20 solids weight%.
However, when a trifunctional or higher functional polyol or polyisocyanate compound is used, it is desirable to employ a compounding ratio and a synthesis method in consideration of prevention of gelation during a synthesis reaction.

The crosslinking reaction between the active hydrogen atom and the crosslinking agent (B) having an active hydrogen atom, the isocyanate group of the aqueous polyurethane microgel comprising the polyurethane resin skeleton (A) may be performed at 5 ° C. to 50 ° C. I can do it 1
Reaction temperatures in the range of 0 ° C to 40 ° C are preferred.

The crosslinking agent (B) having an active hydrogen atom which reacts with an isocyanate group is the same as the above-mentioned polyurethane skeleton (A)
The ratio of the active hydrogen to the NCO group therein is approximately equivalent, and the range of 0.7 to 2.0: 1.0 is desirable.

An active energy ray-curable unsaturated group which does not react with an active hydrogen atom such as a methacryloyl group at 50 ° C. or lower can be introduced into the molecule of the aqueous polyurethane microgel. Compound (A-3) having an active energy ray-curable unsaturated double bond and a hydroxyl group in the molecule is represented by (A-1)
It can react with (A-2) as a polyol component together with (A-4) or react with a part of the isocyanate group after the reaction of (A-1), (A-2) and (A-4). The concentration of the unsaturated group in the case of the active energy ray-curable microgel is adjusted to 0 to 4.5 equivalents / kg, more preferably 0 to 3.0 equivalents / kg.

The concentration of unsaturated groups in the active energy ray-curable composition obtained by mixing the non-gel active energy ray-curable polyurethane composition and the aqueous polyurethane microgel is preferably 1.0 to 4.5 equivalent /. kg, more preferably 1.5 to 3.0 equivalents / kg.

The above polyisocyanate compound (A-
Specific examples of 1) include ethylene diisocyanate, 1,6-hexamethylene diisocyanate,
2,4-trimethylhexamethylene diisocyanate,
Aliphatic diisocyanate such as 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4-diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, norbornane diisocyanatomethyl, isopropyl Examples include alicyclic diisocyanates such as lidenedicyclohexyl-4,4'-diisocyanate or diisocyanates such as aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, and tolylene diisocyanate. I can do it.

Further, the diisocyanate (A-
Adduct of polymer (1) or diisocyanate (A-1) with polyols such as trimethylolpropane and ethylene glycol, or diisocyanate (A-
The urea-modified, buret-modified, carbodiimide-modified, uretonimine-modified, allohanate-modified and the like of 1) are applicable.

The polyol component (A-2) comprises at least one polyol resin selected from the group consisting of polyester polyols, polyether polyols, polyester polyether polyols and polycarbonate polyols, and a polyol component comprising other polyols. Become.

As typical examples of other polyols, first, as a diol component or a compound having an equivalent effect, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol,
2-methyl-1,3-propanediol, dipropylene glycol, 1,3-butylene glycol, 1,4 butylene glycol, neopentyl glycol, 1,6 hexanediol, 3-methyl-1,5-pentanediol, 2 -Ethyl-1,3-hexanediol, 2-butyl-2ethyl-1,3-propanediol, cyclohexane-1,4-dimethanol, spiroglycols, monoglycidyl ethers, monoepoxides. .

Next, examples of the trivalent or higher polyol component include polyhydric alcohols such as glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol, or compounds having an equivalent effect. Further, a polybutadiene polyol, a polypentadiene polyol, an epoxy resin or the like can be mentioned as an alcohol component or a component having an equivalent effect.

The above-mentioned polyester polyol can be obtained by various known methods, and typical methods are shown below. One method for obtaining a polyester polyol is by subjecting a polyhydric alcohol or a compound having an equivalent effect to a polyhydric alcohol to a dehydration or dealcoholation reaction or an addition reaction.

The polyester polyol is obtained by addition-polymerizing a lactone monomer such as ε-caprolactone or β-methyl-δ-valerolactone using the above-mentioned polyols, polyhydroxy compounds or amines as starting materials. As a result, a polylactone polyester polyol is obtained.

As representatives of the above polybasic acids, succinic acid,
4 to 2 carbon atoms such as succinic anhydride, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid
Compounds having the same effect as dicarboxylic acids, such as aliphatic dicarboxylic acids and dimethyl esters thereof, and fatty acids such as hexahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, hexahydrophthalic acid, and tetrahydrophthalic acid. Aromatic dicarboxylic acids such as cyclic dicarboxylic acid, orthophthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, terephthalic acid dimethyl ester or compounds having an equivalent effect thereof, trimellitic acid, pyromellitic anhydride, methyl maleate Cyclohexene tetrabasic acid anhydride (for example, manufactured by Dainippon Ink and Chemicals, Inc., trade name: Epicron B4400), and the like.

Examples of the polyhydric alcohol used as a raw material of the polyester polyol include, among the polyols (A-2) listed above as representatives of other polyols, diols, compounds having the same effect as diols, polyhydric alcohols Or a compound having an effect equivalent thereto.

In the present invention, α,
An unsaturated polyester polyol having a double bond at the β-position can be used. The double bond at the α and β positions is an unsaturated dibasic acid having a double bond at the α and β positions such as maleic acid, fumaric acid and itaconic acid as a part of the dibasic acid constituting the polyester component. Introduced using

Such a polyester polyol may be added with a titanate such as tetraisopropyl titanate or tetrabutyl titanate or a tin-based catalyst such as dibutyltin oxide as an esterification catalyst, if necessary, or to promote dehydration. To a solvent such as xylene, Solvesso 100, or Solvesso 150, and dehydration or desorption by a known method such as adding an additive such as triphenyl phosphite or trinonyl phenyl phosphite to prevent oxidative coloring. Obtained by alcohol condensation. The average molecular weight of the polyol and the number of functional groups of the hydroxyl group can be determined by blending the hydroxyl equivalent of the alcohol component with an equivalent ratio of at least 1 equivalent to the carboxyl equivalent of the acid component. However, when an acid or alcohol component having three or more functionalities or a component having an effect equivalent thereto is used, it is desirable to adopt a synthesis method that takes into consideration the prevention of gelation during synthesis.

Examples of the polyether polyol include the polyols described above, and 4,4-dihydroxydiphenyl-2,2-propane (bisphenol A),
Examples thereof include polyhydroxy compounds such as dihydroxydiphenyl-2,2-methane, and polyether polyols obtained by addition-polymerizing ethylene oxide, propylene oxide, tetrahydrofuran, or the like using amines or the like as a starting material.

The polyester polyether polyol can be obtained by subjecting ethylene oxide, propylene oxide, tetrahydrofuran or the like to addition polymerization using the above-mentioned polyester polyol as a starting material. As another method, the above polyether polyol is used as a starting material and ε
-Caprolactone, β-methyl-δ-valerolactone, and other lactone monomers can be obtained by addition polymerization.

Representative examples of the compound (A-3) having an active energy ray-curable unsaturated double bond and a hydroxyl group include monohydroxy compounds such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate and hydroxybutyl methacrylate. Monomethacrylate or glycerin dimethacrylate, acrylate G70
1 (manufactured by Kyoeisha Chemical Co., Ltd.), monohydroxytrimethacrylate such as pentaerythritol trimethacrylate, dihydroxymonomethacrylate such as glycerin monomethacrylate, and addition polymerization of ethylene oxide, propylene oxide and tetrahydrofuran. And the like. Further, a product obtained by reacting half urethane obtained by reacting a diisocyanate having two isocyanate groups having different reactivities with monohydroxymonomethacrylate, monohydroxydimethacrylate, and dialkanolamine is also referred to as (A- It can be cited as a typical example of 3).

Representative examples of the diisocyanates having two isocyanate groups having different reactivities include isophorone diisocyanate and tolylene diisocyanate.

Representative of the above dialkanolamines are diethanolamine, diisopropanolamine,
Examples thereof include dipropanolamine and dibutanolamine.

As the compound (A-4) having a salt group, the salt group may be any one of a phosphate ester group, a sulfonic acid group, a tertiary amino group, a carboxyl group, and a neutralizing base thereof. Suitable are diols having the formula: and diamines. When only typical examples are given, polyoxyethylene glycol, polyoxyethylene diaminopropyl ether, trimethylolpropane monophosphate, trimethylolpropane monosulfate, at least a part of the dibasic acid component is sodium sulfo amber. Polyester diols which are acids or sodium sulfoisophthalic acid, N-methyldiethanolamine, diaminocarboxylic acids such as lysine, cystine and 3,5-diaminocarboxylic acid, 2,6-dihydroxybenzoic acid and especially dihydroxyalkanoic acids such as 2,2 -Dihydroxypropionic acid and carboxyl group-containing polycaprolactone diol obtained by reacting 2,2-dihydroxypropionic acid with ε-caprolactone.

The necessary amount of the salt group is introduced into the non-gel active energy ray-curable polyurethane composition or the polyurethane resin skeleton (A). Determined by type and combination. Among the above examples, particularly preferable as the hydrophilic group are those having one or two selected from a carboxyl group and a sulfonate group in the molecule, or a mixture of those having both. In particular, introduction of a carboxyl group is easy to balance and operate in various points. In this case, the acid value of the solid content is preferably in the range of 10 to 80, more preferably in the range of 30 to 60.

The reaction for producing the non-gel active energy ray-curable polyurethane compound or the polyurethane resin skeleton (A) of the aqueous polyurethane microgel can be carried out in an organic solvent. A catalyst and a polymerization inhibitor can be added.

As such an organic solvent, use of acetone, methyl ethyl ketone, ethyl acetate, n-hexane, or the like having a lower boiling point than water is preferable in consideration of concentration in the final step. When an organic solvent having a boiling point lower than that of water is used, a dispersion containing substantially only water as a medium can be obtained by concentration. Of course, there is no problem in using an organic solvent having a higher boiling point than water as long as the dispersion stability is not impaired.

Examples of the urethane catalyst include tin catalysts such as dibutyltin laurate and stannous octoate;
An amine catalyst such as triethylenediamine is exemplified.

Typical examples of the polymerization inhibitor include tertiary butyl hydroquinone, methoquinone and the like.

In the present invention, the non-gel active energy ray-curable polyurethane composition or the polyurethane resin skeleton (A) of the aqueous polyurethane microgel is usually produced in a state of being dissolved in an organic solvent. Can be dispersed in an aqueous medium by a known and commonly used method.

For example, if the non-gel active energy ray-curable polyurethane composition or the polyurethane resin skeleton (A) of the polyurethane microgel precursor contains a carboxyl group as a hydrophilic group, a part or part of this is included. The resin is dispersed in water together with a base for neutralizing the whole. As a method, the resin solution can be gradually added and dispersed while stirring the water containing the base. Conversely, water containing a base may be gradually added dropwise to the resin solution for phase inversion.

In general, since a resin dispersion having a fine particle diameter and a stable resin dispersion is easily obtained, water containing a base is gradually added dropwise to a place where the resin solution is well stirred, and the phase is changed. More preferably, the method is used.

Representative examples of basic substances applicable for neutralizing and ionizing carboxyl groups in the resin include lithium hydroxide, potassium hydroxide, sodium hydroxide, trimethylamine, triethylamine and tripropylamine. And tertiary alkylamines such as morpholine, and tertiary alkanolamines such as dimethylethanolamine and diethylethanolamine. Among these bases, triethylamine and dimethylethanolamine, which have good dispersibility and high volatility and hardly remain in the coating film, are preferred. The above bases may be used alone or in combination of two or more. The amount of the base used is generally 0.1 to the carboxyl group in the resin.
1 to 2.0 equivalents are preferred, more preferably 0.3 to
1.5 equivalents.

Representative examples of the crosslinking agent (B) having an active hydrogen atom that reacts with the isocyanate group include ethylamine, propylamine, nbutylamine, hydrazine, ethylenediamine, and the like.
Propylenediamine, butylenediamine, hexamethylenediamine, diethylenetriamine, aliphatic amines such as triethylenetetramine or tetraethylenepentamine, cyclohexylenediamine, isophoronediamine,
Alicyclic amines such as norbornanediaminomethyl, tolylenediamine, xylenediamine, phenylenediamine,
Aromatic amines such as tris (2-aminoethyl) amine and 2,6 diaminopyridine, γ-aminopropyltrimethoxysilane, γ-dibutylaminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-
Aminosilanes such as β (aminoethyl) γ-aminopropyltrimethoxysilane or N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane.

The weight ratio of the non-gel active energy ray-curable polyurethane composition thus obtained to the polyurethane microgel particles is from 100/5 to 20/10.
0, preferably in a range of 100/10 to 50/100, and prepared as an active energy ray-curable aqueous composition.

The active energy ray-curable aqueous composition of the present invention may be diluted with an organic solvent such as water or alcohol, and may be diluted with pigments, dyes, emulsifiers, surfactants, matting agents, thickeners, Heat stabilizers, leveling agents, defoamers, fillers, antisettling agents, antioxidants, plasticizers, vinyl crosslinking agents,
Active energy ray curing polymerization initiator, thermal decomposition radical initiator, known polyester resin, polyamide resin, shellac or modified shellac, rosin derivative, polyurethane, acrylic copolymer, etc., various water-soluble resins, or slightly hydrophobic It may be a composition in which a water-soluble resin or the like is added as necessary together with an emulsifier or an organic solvent as long as storage stability or dispersibility is not impaired.

Examples of the coloring agent include pigments and dyes each alone or in combination, such as soluble or insoluble organic pigments such as azo, phthalocyanine, and naphthol, titanium oxide, red iron oxide, carbon black, calcium carbonate, and the like. Inorganic pigments such as barium sulfate, organic dyes of metal complex salts and the like, alone or in combination. The colorant may be a dry powder, but a press cake containing water may also be used.

The aqueous paint or printing ink comprising the active energy ray-curable aqueous composition of the present invention may be prepared by any method, and for example, can be prepared according to the following formulation. That is, the colorant of the press cake or the dry powder is usually used as a mixture of a part of the active energy ray-curable composition and another aqueous resin, or another aqueous resin alone, and if necessary, a neutralizing agent and a dispersing agent. Along with the agent or antifoaming agent, the mixture is dispersed in a conventional meat mill such as a ball mill, a sand mill or another media mill to form a colorant base. The colorant base is mixed with other resin components including the remaining active energy ray-curable water-dispersible polyurethane compound and, if necessary, water, a solvent, a neutralizing agent, an antifoaming agent, and other additives to form a desired aqueous solution. It is finally prepared as an active energy ray-curable aqueous coating composition for use in paints or printing inks.

The active energy ray-curable composition of the present invention can be cured by a known method. For example, in the case of curing with an electron beam, after coating on the adherend and evaporating and drying water and a small amount of an organic solvent when included,
Acceleration voltage 20 to 2000 KeV, preferably 150 to 3
Using a 00 KeV electron beam irradiation device, a cured product is obtained by irradiation in an inert gas atmosphere containing or not containing a small amount of oxygen so that the total irradiation dose becomes 5 to 200 KGy, preferably 20 to 150 KGy. I can do it.

Further, in the present invention, other curing means, for example, a method of curing in air or an inert gas atmosphere by ultraviolet rays obtained from a mercury lamp, a xenon lamp or the like, an energy related to heat such as infrared rays, high frequency waves or microwaves , Ie, a method of curing by heating. When using high-energy ionizing radiation having an action of emitting secondary electrons by being absorbed by a substance such as the above-mentioned electron beam, X-ray, and gamma ray, it is not particularly necessary to add a polymerization initiator. When heat curing or ultraviolet curing is used, it is preferable to add a photopolymerization initiator or a thermal polymerization initiator. In addition, one kind selected from the above-described curing method using ionizing radiation, a curing method using ultraviolet light, and a method using heat curing can be used alone, or two or more methods can be used simultaneously or before and after each other.

Examples of these polymerization initiators by heat or light include 2,2′-azobisisobutyronitrile,
2,2′-azobis (2-methylbutyronitrile),
Azo initiators such as 2,2'-azobis (2,4-dimethylvaleronitrile) and 1,1'azobis (cyclohexane-1-carbonitrile), ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide , Hydroperoxides such as cumene hydroperoxide and tert-butyl peroxide, dialkyl peroxides such as di-tert-butyl peroxide and dicumyl peroxide, tert-butylperoxylaurate, t
Peroxide esters such as peroxyesters such as tert-butylperoxybenzoate can be exemplified.

Examples of photopolymerization initiators include intermolecular hydrogen abstraction initiators such as benzyl, benzophenone, Michler's ketone, dibenzosuberone, 2-ethylanthraquinone and isobutylthioxanthone, benzoin ethyl ether, diethoxyacetophenone, and the like. Benzyl methyl ketal, 1-hydroxycyclohexyl phenyl ketone 4- (2-hydroxyethoxy) -phenyl (2-hydroxy-2-propyl) ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one,
Acylphosphine oxide, 2-methyl-1- [4
A known and commonly used organic phase radical polymerization initiator such as an initiator of an intramolecular bond cleavage type such as-(methylthio) phenyl] -2-morpholinopropane-1 can be used. When these organic phase initiators are used, they are preferably added to an organic solvent solution before dispersing the resin solution in water.

On the other hand, examples of the initiator which can be used in addition to the aqueous dispersion of the polymerizable unsaturated group-containing resin include potassium persulfate, ammonium persulfate, azobisbutyronitrile or its hydrochloride, and the like. Further, if necessary, an organic peroxide such as cumene hydroperoxide or tert-butyl hydroperoxide can be used. In addition, a so-called redox-based system using a combination of these persulfates and peroxides and a metal ion such as iron ion, or a reducing agent such as sodium sulfoxylate formaldehyde, sodium pyrosulfite or L-ascorbic acid is used. Agents can also be used.

The amount of the polymerization initiator used may be appropriately selected from the range of 0.2 to 20% per solid content excluding the colorant, but is particularly preferably in the range of 0.5 to 10%.

The active energy ray-curable composition of the present invention can be applied to objects to be coated and printed materials including wood, metal, glass, cloth, leather, paper and plastic, and can be applied by brush coating, spray coating, flow coating. Various coating methods and printing methods such as dip coating, vacuum coating, roll coating, gravure printing, and flexographic printing are applicable.

[0069]

Next, the present invention will be described more specifically with reference examples and examples. In the following, all parts and percentages are by weight unless otherwise specified. In the following text, viscosity represents Gardner viscosity.

[Preparation Example 1] Plaxel L was placed in a reactor equipped with a stirrer equipped with a reflux condenser, a nitrogen inlet, and a thermometer.
205AL (molecular weight 500, lactone polyester diol manufactured by Daicel Chemical Industries, Ltd.) 36.0 parts, dimethylolpropionic acid 20.5 parts, trimethylolpropane 4.54 parts, butylethylpropanediol 10.2
Part, polyethylene glycol PEG # 600 2.54
Parts, 96.1 parts of norbornane diisocyanatomethyl, N
-Methylpyrrolidone 32.1 parts, ethyl acetate 229.6
Parts, 0.18 part of methquinone and 70 ° C. while stirring.
The temperature was raised in 0.5 hours until the reaction at 70-75 ° C for 5 hours,
The nitrogen inlet tube was switched to an air inlet tube, and metquinone 0.1.
034 parts, glycerol dimethacrylate (manufactured by NOF Corporation) 50.1 parts, stannous octoate 0.11 part,
Was added and reacted again at 70 to 75 ° C. for 6 hours to obtain a solution of a poly (ester) urethane resin skeleton. After cooling to 50 ° C., 15.4 parts of triethylamine and 508.6 parts of pure water were gradually added to the solution, and the mixture was kept at 35 to 40 ° C. for 30 minutes. 0.11 parts of Surfynol AK02 (manufactured by Nissin Chemical Industry Co., Ltd.) was added, and the mixture was distilled under reduced pressure at 50 ° C.
Ethyl acetate was removed to remove nonvolatile matter: 30.3%, Gardner viscosity: UV, transparent non-gel active energy ray-curable aqueous urethane methacrylate composition (JY-1)
Was prepared. Methacryloyl group concentration = 1.8 equivalents / kg Acryloyl group concentration = 0 equivalents / kg Solid acid value: 40 KOHmg / g

[Preparation Example 2] In a reactor equipped with a stirrer equipped with a reflux condenser, an air introduction pipe, and a thermometer, Clapol P was added.
-510 (molecular weight 500, polyester diol manufactured by Kuraray Co., Ltd.) 38.7 parts, dimethylolpropionic acid 2
2.0 parts, trimethylolpropane 4.88 parts, butylethylpropanediol 3.6 parts, polyethylene glycol PEG # 600 2.7 parts, 1,3-bis (isocyanatomethyl) cyclohexane 97.2 parts, Blemmer GLM7 6.6 parts, 33.7 parts of N-methylpyrrolidone, 143 parts of ethyl acetate, and 0.09 part of methquinone were added, and the temperature was raised to 70 ° C. in 0.5 hour with stirring, and reacted at 70 to 75 ° C. for 5 hours. 0.113 parts of Methoquinone, Biscoat #
214HP (manufactured by Osaka Organic Chemical Co., Ltd.) (54.4 parts) and stannous octylate (0.11 part) were added and reacted again at 70 to 75 ° C. for 6 hours to obtain a solution of the poly (ester) urethane resin skeleton. Obtained. After cooling to 50 ° C., 16.5 parts of triethylamine and 533.5 parts of pure water were gradually added to this solution,
Maintained at 35-40 ° C for 30 minutes. Surfynol AK
02 (manufactured by Nissin Chemical Industry Co., Ltd.)
Distillation under reduced pressure at ℃, the ethyl acetate was removed and the nonvolatile content: 2
A 9.2%, Gardner viscosity: + J, non-gel active energy ray-curable aqueous urethane (meth) acrylate composition (JY-2) having a transparent appearance was prepared. Methacryloyl group concentration = 1.2 eq / kg Acryloyl group concentration = 1.0 eq / kg Solid acid value: 40 KOHmg / g

[Polyurethane Microgel Example 1] Aqueous polyester urethane microgel Spensol L-512 (manufactured by Reichhold) Nonvolatile content: 30.0%, Viscosity: AB Appearance transparent

(Test Examples for Clear Coatings) The non-gel active energy ray-curable compositions (JY-1 and JY-1) obtained in Preparation Examples
Y-2) and (polyurethane microgel: Spensol L-512) were blended as shown in Tables 1 and 2 to prepare Example compositions and Comparative Examples. A storage stability test was performed on the four prepared compositions. Furthermore, the painted test piece is an aluminum plate,
Veneer plywood, art paper, dry film thickness 20 ~ 30μ
m was applied with a bar coater and dried at 60 ° C. for 5 minutes with a blow dryer. Thereafter, ultraviolet irradiation was performed using a 120 W high-pressure mercury lamp with an irradiation amount of 350 mJ / cm ² . Regarding the coating film after the ultraviolet irradiation, a pencil hardness test, a MEK resistance test, and a coating smoothness test were performed on a TFS plate (tin-free steel plate for can coating). A pencil hardness test, a MEK resistance test, a coating film smoothness test, and a cellophane peel test were performed, and an MEK resistance test and a smoothness test were performed on art paper. Each test method is shown below, and the test results are shown in Tables 1 and 2.

(Pencil hardness test) A precision drawing pencil (made by Uni-Mitsubishi Pencil) cut into a cylindrical shape is scratched at an angle of 45 degrees with respect to the painted surface. It is shown by the hardness of the hardest pencil that does not break the coating film twice or more repeated 5 times.

(MEK rubbing test) Absorbent cotton wrapped in gauze was mixed with methyl ethyl ketone (MEK), and 2 kg
Rubbing the coating film by applying a load of
It measures the number of rubbings until 0% exposure.
The measurement was performed using an IC type rubbing tester type I (manufactured by Riken Engineering Co., Ltd.).

(Cellophane Tape Peeling Test) According to one method of the adhesion strength test, a cut line having a depth reaching the base material is formed on the surface of the test piece in a crosswise shape, and a cellophane tape (manufactured by Nichiban Co.) having a width of 24 mm is formed. After pasting, quickly 18 by hand
Peel 0 degree. The results of the adhesion strength test are examined by examining the state of the remaining coating film, and the results are indicated by 全 く when no peeling is observed at all, Δ when peeling slightly along the cross, and x when peeling.

(Smoothness Test of Coating Film) The compositions of Examples 1 and 2 and Comparative Examples 1 and 2 were applied by a bar coater to TFS board and art paper, and sprayed to veneer plywood, and dried. The state of the coated surface of the coated film was observed, and the edge of the object to be coated was raised (frame property) and paint defects were examined. The evaluation criteria are shown below.・: No frame property, and coating film defects such as bumps were 1/1 cm ² . Hereinafter △ · · frame of somewhat there, lumps or the like coating film defects is 1-4 or less / 1 cm ^2. × ・ ・ There is a picture frame property, 5 or more coating defects such as bumps / 1cm
²

(Preservation Stability of Compositions) The compositions of Examples 1 and 2 and Comparative Examples 1 and 2 were put in 100 ml glass bottles, sealed, kept at 40 ° C. in a shielded oven, and observed with time for appearance change. I do. The evaluation criteria are shown below.

・: No change to slight turbidity △: white turbidity to slight precipitation × ・ ・ Precipitation to gelation

[0080]

[Table 1]

In the table, “Darocure” refers to “Darocure D-1173, a photoinitiator manufactured by Merck Japan K.K.”
"-512" is "Spiensol L-5 manufactured by Reichhold"
12 "and" Non-gel / gel weight ratio "means" solid content ratio of non-gel urethane compound and urethane microgel particles "
"Hardness test" means "Pencil hardness test", "MEK resistance"
Represents "MEK resistance test", and "smoothness" represents "coating film smoothness test".

[0082]

[Table 2]

[0083]

As is clear from the above results, the active energy ray-curable aqueous composition of the present invention has good storage stability and excellent printability and coating suitability, so that the coating surface is smooth and free from defects. Coatings, coatings, glossy varnishes, gravure inks for coating or printing on building materials, metals, paper, etc., which provide a film and have excellent curability, adhesion, and chemical resistance, and have low odor and skin toxicity and excellent safety and hygiene It is extremely useful as a vehicle for applications such as flexographic inks.

Claims (7)

[Claims] 1. A non-gel active energy ray-curable polyurethane composition having a salt group and an active energy ray-curable unsaturated group in the molecule of a polyurethane resin skeleton dispersed in water, and a polyurethane microparticle dispersed in water. An active energy ray-curable aqueous composition, comprising: gel particles. 2. The non-gel active energy ray-curable polyurethane composition, wherein the unsaturated group is an active energy ray-curable unsaturated group which does not react with a crosslinking agent having an active hydrogen atom at 50 ° C. or lower. 2. The active energy ray-curable aqueous composition according to 1. 3. The polyurethane microgel particles,
Gel-like film-forming polyurethane resin particles having a structure in which a polyurethane resin skeleton and a chain between the skeletons are chain-extended or cross-linked via a urethane bond or a urea bond, wherein the polyurethane resin particles are dispersed in water having a salt group. The active energy ray-curable aqueous composition according to claim 1, which is a body. 4. The method according to claim 1, wherein the polyurethane resin skeleton is at least one resin skeleton selected from a polyester urethane resin skeleton, a polyether urethane resin skeleton, a polyether polyester urethane resin skeleton, and a polycarbonate polyurethane resin skeleton. Active energy ray-curable composition. 5. The method according to claim 1, wherein the polyurethane resin skeleton has an isocyanate group, and the crosslinked structure is a crosslinked structure formed by a reaction between the isocyanate group and a crosslinking agent having an active hydrogen atom. Active energy ray-curable aqueous composition. 6. The weight ratio of the non-gel active energy ray-curable polyurethane composition to the polyurethane microgel particles is in the range of 100/5 to 20/100.
The active energy ray-curable aqueous composition according to the above. 7. The non-gel active energy ray-curable polyurethane composition, wherein an active energy ray-curable unsaturated group that does not react with a crosslinking agent having an active hydrogen atom at 50 ° C. or lower is a methacryloyl group or α, The active energy ray-curable aqueous composition according to claim 1, which is an unsaturated group introduced by using an unsaturated dibasic acid having a double bond at the β-position and an unsaturated group of a vinyl ether compound.