JPH0931150A - Urethane prepolymer, active-energy-ray-curable water-base polyurethane resin composition, and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an active-energy-ray-curable water-base polyurethane resin compsn. which is excellent in the blocking resistance of an uncured coating film, in curability, and in solvent resistance after cured. SOLUTION: This urethane prepolymer is obtd. by reacting, as the essential reactants, a product obtd. by the Michael addition of a hydroxy compd. having an active hydrogen atom to double bonds of a compd. having at least two (meth)acryloyl groups, a polyhydroxy compd. having an acidic group, and a polyisocyanate compd. An active-energy-ray-curable water-base polyurethane resin compsn. is prepd. by using the prepolymer.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel and useful urethane prepolymer, and an active energy ray-curable aqueous polyurethane resin composition using the prepolymer. More specifically, the active energy ray-curable aqueous polyurethane resin composition of the present invention can be diluted with water and washed, and can be widely applied as a vehicle for paints, coating agents, adhesives, printing inks and the like. , An aqueous polyurethane resin composition that can be cured by active energy rays such as electron beams and ultraviolet rays.

[0002]

2. Description of the Related Art Recently, the problem of environmental pollution has been pointed out, and
From the viewpoint of safety and hygiene, there is a strong demand for further improvement of the working environment, and technical development and manufacturing are required in consideration of reducing the amount of organic solvent used as much as possible. Conventionally, a so-called urethane acrylate obtained by reacting a (meth) acryloyl compound having a hydroxyl group with a terminal isocyanate group of a urethane prepolymer is used as an electron beam curable composition or an ultraviolet curable composition in combination with a photopolymerization initiator. Although it has a wide range of applications as a vehicle for paints, coating agents, adhesives, printing inks, etc., since many of these resins also use a large amount of organic solvent, organic solvents are also used in this field in the sense described above. So-called water-based or solvent-free technology, which is not used as much as possible, has come to the fore, including the development of new materials. In particular, with respect to the water-based resin, the residue at the time of coating can be diluted with water and washed, and it is considered to have great practical advantages.

However, some problems remain with such an aqueous urethane resin. One of them is a performance problem of the water-based urethane resin itself. JP-A-3-1
According to Japanese Patent No. 66216, a part of the terminal isocyanate group of the urethane prepolymer having a carboxyl group,
Disclosed is an aqueous urethane resin composition in which a hydroxy compound having a (meth) acryloyl group such as hydroxyalkyl (meth) acrylates is reacted with water and then chain-extended. Also, before that, JP-A-62
According to JP-A-22816, for the purpose of suspending two kinds of functional groups of an acryloyl group and a carboxylate group on a part of the terminal isocyanate group of the urethane prepolymer, a hydroxyalkyl acrylate and an aminocarboxylic acid Na salt are also used. After reacting with, a water-based and chain-extended urethane resin aqueous emulsion is disclosed.

However, what can be said in common with these water-based urethane resins is that both the acryloyl group and, in the latter case, the carboxylic acid group are further pendant, and in addition, chain extension is carried out. The method of utilizing the terminal isocyanate group of is adopted. Therefore, there is a natural limit to the suspension of the acryloyl group, which is an important factor for increasing the curability and crosslinkability,
In terms of polymer design, there is a drawback in that it is difficult to obtain a suspension density of acryloyl groups that shows sufficient performance. For that reason, with respect to abrasion resistance and solvent resistance that often appear along with it, in the case of such a resin, the conventional "solvent type",
Alternatively, it is still inferior to the “aqueous solution type”, and the actual situation is that it has not reached a satisfactory level.

Another problem is that the viscosity of aqueous resins changes considerably over time. In particular, "aqueous solution type" resins tend to have a large tendency to decrease in viscosity and continue to change over a relatively long period of time, which may cause difficulties such as unstable actual coating conditions. It has not been fully resolved yet. In addition, it is also used as a coating agent for urethane acrylate. For example, when it is used as an electron beam or UV-curable anchor agent (intermediate coating agent) for decorative paper for building materials, a clear (topcoating agent) is finally used. Since it is necessary to wind it once in an uncured state before topcoating, sufficient blocking resistance is required for the uncured coating film itself, but with a normal urethane acrylate, this is irrespective of whether it is water-based or solvent-based. The reality is that there is nothing that meets the requirements.

[0006]

Therefore, the object of the present invention is to provide curability, solvent resistance, and further blocking resistance of an uncured coating film, which can be applied to applications where existing aqueous resins cannot be satisfied. It is to provide an active energy ray-curable water-based urethane resin composition that also has the above-mentioned properties and has a relatively small change in viscosity as a water-based resin.

[0007]

The inventors of the present invention have completed the present invention as a result of earnest studies in view of the above-mentioned actual conditions. That is, the present invention, in order to achieve the above objects, as a new and useful urethane prepolymer,
(A) a product obtained by Michael-adding a hydroxy compound having active hydrogen to a double bond of a compound having two or more (meth) acryloyl groups (abbreviated as Michael adduct), and (b) having an acidic group Provided is a urethane prepolymer which is obtained by reacting a polyhydroxy compound and (c) a polyisocyanate compound as essential components.

Further, in the present invention, after neutralizing a urethane prepolymer having a (meth) acryloyl group, an acidic group, and a terminal isocyanate group, and dispersing it in an aqueous medium,
The present invention provides an active energy ray-curable aqueous polyurethane resin composition, characterized in that the urethane prepolymer in the aqueous polyurethane resin composition which is chain-extended with a polyamine is as described above.

In the present invention, the first step is (meth)
In a double bond of a compound having two or more acryloyl groups,
A product obtained by Michael-adding a hydroxy compound having active hydrogen is obtained, and as a second step, the product (abbreviated as Michael adduct) further has a polyhydroxy compound having an acidic group and a polyisocyanate compound as essential components. The present invention also provides a method for producing a urethane prepolymer, which comprises reacting by adding another polyhydroxy compound as an optional component.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The urethane prepolymer of the present invention is a polyfunctional (meth) acrylate compound having a high number of (meth) acryloyl functional groups used in the synthesis of the above-mentioned Michael adduct which is an essential component thereof. The more it is used, the more the (meth) acryloyl group can be suspended in a block form on the urethane side chain, and thus the suspension density can be increased accordingly.
Therefore, the active energy ray-curable aqueous polyurethane resin composition of the present invention obtained by dispersing the prepolymer in an aqueous medium and then extending the chain with a polyamine is a conventionally known aqueous polyurethane resin having a (meth) acryloyl group. Compared with the above, it has excellent characteristics in terms of solvent resistance, abrasion resistance, and blocking resistance of an uncured coating film, in which the crosslinking property and the curability can be freely adjusted.

Hereinafter, the present invention will be described in detail. In the following text, the (meth) acryloyl group refers to both an acryloyl group and a methacryloyl group. When producing a urethane prepolymer having a (meth) acryloyl group, an acidic group, and a terminal isocyanate group of the present invention, two (meth) acryloyl groups are used as a method for introducing a (meth) acryloyl group into a urethane side chain. A product obtained by Michael-adding a hydroxy compound having active hydrogen to the double bond of the above compound (referred to as a Michael adduct) is used as an essential component.

Regarding the "Michael addition reaction" used as a reaction for producing the compound, Organic Rea is used.
action Vol. 5, p. 79, Methoden
der Organischen Chemie Vo
l. 9, page 120, Vol. Examples of reactions are described on pages 11/1 and 277. According to these, primary and secondary amino groups, mercapto groups, phenolic hydroxyl groups, β
In the case of a diketone, an acetoacetyl group, or the like, a non-catalyst system, or if necessary, a catalyst system, to a double bond such as α, β-unsaturated carboxylic acid ester or α, β-unsaturated nitrile,
It is described that so-called Michael addition proceeds in a nucleophilic ionic reaction.

For example, in the case of a primary amino group, an α, β-unsaturated carboxylic acid or its ester can be obtained in a non-catalytic system.
Michael addition readily occurs at room temperature to produce secondary amines.
Also in the case of primary mercaptan, for example, by using a tertiary amine as a catalyst, Michael addition to a double bond of an α, β-unsaturated carboxylic acid ester such as an acrylic acid ester is carried out by a nucleophilic ionic reaction in the same manner as above. Progresses to produce sulfide.

In the present invention, the hydroxy compound having active hydrogen means, therefore, the hydroxy compound having active hydrogen capable of Michael-adding to the α, β-unsaturated double bond as described above, specifically, Hydroxy compounds having primary, secondary and secondary amino groups, primary and secondary mercapto groups, phenolic hydroxyl groups, acetoacetyl groups, and β-diketone structures are included. Among them, a hydroxy compound having a primary amino group and / or a primary mercapto group is particularly preferable.

Therefore, a product obtained by Michael-adding a hydroxy compound having active hydrogen to a double bond of a compound having two or more (meth) acryloyl groups disclosed in the present invention is, for example, a primary amino group. In the case of a hydroxy compound having a group, a primary amino group is added to a part of the (meth) acryloyl group of a compound having two or more (meth) acryloyl groups by a nucleophilic ion reaction, and the resulting 2 Refers to a hydroxy compound in which the remaining (meth) acryloyl groups are pendant via a bond with a primary amine.

In this case, since the secondary amine produced has a relatively low reactivity with the (meth) acryloyl group at room temperature (at least 30 ° C. or lower), it has both an active hydrogen and a hydroxyl group of the secondary amine (meth). ) As an acryloyl compound, contributes to the reaction with polyisocyanate. Similarly, even in the case of a hydroxy compound having a primary mercapto group, a part of the (meth) acryloyl group of a compound having two or more (meth) acryloyl groups has a mercapto group by a nucleophilic ion reaction. Refers to a hydroxy compound that has been added to suspend the remaining (meth) acryloyl group via a sulfide bond.

Among the above-mentioned hydroxy compounds having active hydrogen included in the present invention, for example, as the hydroxy compound having a primary amino group, one primary amino group and one hydroxyl group are included in the same molecule. The number of the compound is limited to two or two, but the same molecule may further have a secondary amino group as another functional group. As a specific example,
Monoethanolamine, 1-aminopropane-2,3-
Examples thereof include diol, N- (2-aminoethyl) ethanolamine, N- (3-aminopropyl) ethanolamine, and other ammonia adducts of monooxirane compounds such as cyclohexene oxide, and oxycarboxylic acid adducts of monoaziridine compounds. Among them, monoethanolamine is particularly preferable.

Among the hydroxy compounds having active hydrogen included in the present invention, for example, the hydroxy compound having a primary mercapto group includes one or two primary mercapto groups in the same molecule, and A compound having two or more hydroxyl groups is included. Further, a compound having one primary mercapto group and two hydroxyl groups in the same molecule is particularly preferable. The mercaptan may be aromatic, aliphatic, or alicyclic, but a hydroxy compound containing an aliphatic primary mercapto group is more preferable. Specific examples include 1-thioglycerin, 2-thioglycerin, glycerin monothioglycolate,
Hydrogen sulfide adduct of hydroxy compound having one α, β-unsaturated double bond, such as glycerin monomercaptopropionic acid ester and glycerin mono (meth) acrylate,
The mercapto group, such as the ring-opening product of a thiirane compound such as cyclohexene episulfide with diethanolamine
And a hydroxy compound having two mercapto groups such as a hydrogen sulfide adduct of a so-called epoxy acrylate such as a modified product of acrylic acid or methacrylic acid of bisphenol A / diglycidyl ether. Among them, 1-thioglycerin is particularly preferable.

The compound having two or more (meth) acryloyl groups used in the Michael addition reaction with the hydroxy compound having active hydrogen in the present invention is:
Any commonly known so-called polyfunctional (meth) acrylic monomers and oligomers can be applied without any particular problem. As the (meth) acryloyl group functional number of the compound, those having 2 to 6 functional groups are preferably used.

Specific examples include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth).
Acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, dicyclopentane dimethanol di (meth) acrylate, ethylene oxide modified bisphenol A di (meth) acrylate, etc. Of bifunctional (meth) acrylates, pentaerythritol tri (meth) acrylate,
Trifunctional (meth) acrylates such as trimethylolpropane tri (meth) acrylate, propylene oxide-modified trimethylolpropane / (meth) acrylate, ethylene oxide-modified trimethylolpropane / (meth) acrylate, and ethylene oxide-modified isocyanuric acid / (meth) acrylate. ) Acrylates, tetrafunctional (meth) acrylates such as pentaerythritol tetraacrylate, and other polyfunctional (meth) acrylates include dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and ε.
-Caprolactone-modified dipentaerythritol hexa (meth) acrylate, phosphazene hexamethacrylate, and the like, and one of the compounds exemplified above or 2
More than one species can be used.

A hydroxy compound having active hydrogen in the present invention, for example, a hydroxy compound having a primary amino group, and / or a hydroxy compound having a primary mercapto group, and a compound having two or more (meth) acryloyl groups. The ratio of the hydroxy compound 1.
A compound having two or more (meth) acryloyl groups with respect to 0 mol is preferably 0.6 mol or more, and more preferably 0.8 mol to 2.0 mol. This value is 2.0
When it exceeds the molar amount, it does not participate in Michael addition (meta).
Although the proportion of the acryloyl compound increases accordingly, there is no particular problem in the production of the aqueous polyurethane resin composition of the present invention. On the other hand, if this value is less than 0.6 mol, the number of addition reactions occurring in the same molecule becomes too large, and gelation tends to occur in the urethane prepolymer production stage.

The polyhydroxy compound having active hydrogen in the present invention, for example, the hydroxy compound having a primary amino group and / or the hydroxy compound having a primary mercapto group may be used alone or as a mixture thereof.
It can be used and the above molar ratios apply in each case. Further, this molar ratio is applied regardless of the number of functional groups of the compound having two or more (meth) acryloyl groups.

"Additive weight of compound having two or more (meth) acryloyl groups and hydroxy compound having active hydrogen" which is a constituent element of the Michael adduct in the present invention.
Of the total weight of the urethane prepolymer (calculated as solid content) is 5 to 60% by weight, and further 10 to 50% by weight.
Is more preferred. If it is less than 5% by weight, the curability due to active energy rays tends to be poor, and if it exceeds 60% by weight, the thermal stability during resin production tends to be poor.

As the hydroxy compound having an acidic group in the present invention, a hydroxy compound having at least one of a carboxyl group, a sulfonic acid group and a phosphoric acid ester group as an acidic group is suitable. Specific examples include dialkanolcarboxylic acids such as 2,2-dimethylolpropionic acid, and carboxyl group-containing polycaprolactone diols obtained by modifying it with ε-caprolactone, glycerin monophosphate ester, trimethylolpropane monophosphate ester, sodium sulfosuccinate. Examples thereof include polyester polyols containing an acid or sodium sulfoisophthalic acid as a component of a dibasic acid. Of these, 2,2-dimethylolpropionic acid is particularly preferable in terms of technical ease and water-solubility.

In the present invention, when the above-mentioned acidic groups such as carboxyl group and sulfonic acid group are introduced into the urethane prepolymer, the acid value (in terms of solid content) of the prepolymer is 5 to 100 mgKOH / g, and further, 10-50
More preferred is mgKOH / g. If it is less than 5 mgKOH / g, the dispersion stability of the hydrated resin is poor and 100 mg
If it exceeds KOH / g, the water resistance is poor.

As the raw material component for introducing the (meth) acryloyl group used in the present invention, in addition to the above Michael adduct component, other hydroxy compound having a (meth) acryloyl group in the molecule may be used in combination. it can. Examples of other hydroxy compounds having a (meth) acryloyl group in the molecule include glycerin mono (meth) acrylate, an addition product of a dibasic acid such as phthalic acid and glycidyl methacrylate, isophorone diisocyanate and 2-hydroxyethyl acrylate. Acryloyl group-containing dihydroxy compound obtained by reacting a half-urethane produced by a reaction with a molar ratio of 1/1 with a diaminoamine-containing dihydroxy compound such as diethanolamine, and an acryl dialkyl compound such as alkylene oxide-modified bisphenol A diglycidyl ether. Examples thereof include products obtained by adding an unsaturated acid such as acid or methacrylic acid.

In the present invention, a hydroxy compound other than those mentioned above which is reacted with polyisocyanate can be further added as an optional component during the production of the urethane prepolymer. As this component, for example, ε-caprolactone modified diol of ethylene glycol, isophthalic acid,
Polyester diols produced from dibasic acids such as terephthalic acid and adipic acid, and polyols such as methylpentanediol, tetramethylene diol, ethylene oxide adducts of bisphenol A, and polyether polyols such as polyethylene glycol and polypropylene glycol And polycarbonate diols produced from diols such as ethylene glycol and carbonic acid esters.

The polyisocyanate compound used in the present invention is generally a known polyisocyanate used in the production of urethane resins, such as 1,6-hexamethylene diisocyanate and 2,4,4-trimethylhexamethylene diisocyanate. And other aliphatic polyisocyanates, dicyclohexylmethane-4,4′-diisocyanate, methylcyclohexyl-2,4-diisocyanate, isophorone diisocyanate, cyclohexane-1,3 (and 1,4) -diisocyanate methyl, norbornane diisocyanate methyl, etc. Alicyclic polyisocyanates of diphenylmethane-4,4'-
Although any of aromatic polyisocyanates such as diisocyanate, 2,4- (and 2,6-) tolylene diisocyanate, and xylylene diisocyanate can be used, aliphatic and alicyclic polyisocyanates can be used from the viewpoint of weather resistance. Isocyanates are more preferred. The polyisocyanates exemplified above can be used alone or in admixture of two or more.

In the urethane prepolymer according to the present invention, the residual terminal isocyanate groups account for 5 to 60% by weight, and further 10 to 40% by weight, based on all the isocyanate groups used for producing the urethane prepolymer. More preferable. If the amount is less than 5% by weight, the urethane has a high molecular weight and the coating film (uncured) after coating has poor blocking resistance. On the other hand, if it exceeds 60% by weight, the glass transition point of the urethane resin becomes too high, which causes a problem in film-forming property during coating.

The "Michael adduct", which is an essential component of the urethane prepolymer in the present invention, contains a predetermined amount of (meth)
A compound having two or more acryloyl groups is dissolved, if necessary, together with a catalyst in a solvent used for producing a urethane resin, and the above-mentioned hydroxy compound having active hydrogen, for example, the above-mentioned active hydrogen, is stirred in the solution under vigorous stirring. It is synthesized by dropping a solution obtained by diluting a hydroxy compound having a primary amino group and / or a hydroxy compound having a mercapto group with a solvent. The reaction temperature at this time is 40 ° C. or lower, preferably 10 to 30 ° C. The dropping time is 10 to 120 minutes, preferably 20 to 60 minutes.

The urethane prepolymer in the present invention is produced by a hydroxy compound having a primary amino group, and / or
Alternatively, a reaction vessel containing the "Michael adduct" derived from a hydroxy compound having a primary mercapto group may further contain the remaining reaction raw materials, that is, polyisocyanate, a hydroxy compound having an acidic group, and if necessary. , Other hydroxy compounds having a (meth) acryloyl group,
It is carried out by sequentially charging a known urethane-forming reaction under heating conditions after sequentially charging other hydroxy compounds such as polyester polyol.

In the production of the above-mentioned urethane prepolymer, a polymerization inhibitor is used in order to prevent a thermal polymerization reaction of the (meth) acryloyl group, and / or air,
Alternatively, oxygen may be introduced into the reaction atmosphere. Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, 2-t-butylhydroquinone, 2-t-butylphenol, 2,4-di-t-butylphenol, phenothiazine and the like.

As a solvent for producing the urethane prepolymer of the present invention, a generally known solvent can be basically used as long as it is an inert solvent with respect to isocyanate. Specific examples include acetone, methyl ethyl ketone,
Ketones such as methyl isobutyl ketone, aprotic amides such as N-methylpyrrolidone, dimethylformamide and dimethylacetamide, cellosolve esters such as methyl cellosolve acetate, esters such as ethyl acetate and butyl acetate, acetonitrile, propionitrile Nitriles such as, and the like, and one of these, or 2
It is possible to use a mixture of two or more species. Above all,
One or more solvents selected from methyl ethyl ketone, ethyl acetate, and acetonitrile are preferably used.

When the urethane prepolymer of the present invention is produced, the reaction temperature is 10 to 90 ° C., especially 50.
-80 degreeC is more preferable. When the temperature is lower than 10 ° C, the reactivity of isocyanate is low, and when the temperature is higher than 90 ° C, the thermal reaction of the (meth) acryloyl group is likely to occur and the thermal stability of the reaction solution is deteriorated.

In the production of the urethane prepolymer of the present invention, after the reaction for forming the resin skeleton is completed, a part of the terminal isocyanate groups is reacted with a compound having one hydroxyl group or one amino group, followed by neutralization and Chain extension can also be performed.
Examples of the compound having one hydroxyl group in this case include saturated aliphatic alcohols such as methanol and ethanol, alicyclic alcohols such as cyclohexanol, and 2-
Examples thereof include unsaturated aliphatic alcohols such as hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and glycerin monoacrylate monomethacrylate. Examples of the compound having one amino group include saturated aliphatic 2 such as diethylamine and dibutylamine.
Unsaturated amines such as primary amines and diallylamine, aromatic primary amines such as aniline, toluidines and aminophenols, and aromatic secondary amines such as N-methylaniline and N-ethyltoluidines And the like.

In the present invention, an organic basic compound is used as a neutralizing agent for neutralizing the urethane prepolymer having an acidic group such as a carboxyl group, a sulfonic acid group and a phosphoric acid ester group. Tertiary amines are particularly preferred. Specific examples include triethylamine and tri-n-.
Butylamine, triallylamine, N, N-dimethylethanolamine, N, N-diethylethanolamine,
Examples thereof include N-methyldiethanolamine and triethanolamine.

(Production of Aqueous Polyurethane Resin Composition) In the present invention, as a method of chain-extending the urethane prepolymer with polyamine, after neutralizing the prepolymer, if necessary, the optional components described below are added and mixed. Then, deionized water is added to disperse the prepolymer in water in advance, and then an aqueous solution in which a chain extender is dissolved in deionized water is added dropwise, or after neutralizing the prepolymer, if necessary. The following optional components are added and mixed, and the solvent solution thereof is added dropwise to an aqueous solution in which a chain extender is dissolved in deionized water.

Polyamine is used as the chain extender of the urethane prepolymer in the present invention. Specific examples include primary diamines such as ethylenediamine, isophoronediamine, xylylenediamine, norbornanediaminomethyl, diethylenetriamine, and 2-aminoethylethanolamine, or primary amino group-containing polyamines,
Michael adducts of primary diamines such as piperazine, 2-methylpiperazine and ethylenediamine with acrylic acid (and their salts), Michael adducts of ethylene glycol diacrylate with glycine, amino acids containing primary amino groups such as alanine (and Secondary diamines such as its salt). Among the above examples, compounds having two or more secondary amino groups (for example, the above-mentioned secondary diamines) are more preferably used. When both a primary amino group and a secondary amino group are present, it is preferable to use a compound having an equivalent ratio of at least secondary amino group / primary amino group higher than 1.0 as a chain extender.

As the addition amount of the chain extender in the present invention, it is preferable to use a calculated amount of polyamine containing an equivalent amount of amino groups to the isocyanate groups remaining in the urethane prepolymer. When an amount less than the calculated amount is added, the residual isocyanate group is removed in the solvent removal step described later,
It reacts with water by heating and is further decomposed to generate a primary amino group, and Michael addition to the (meth) acryloyl group is likely to occur, which is not preferable. Further, when the amount added is larger than the calculated amount, the amine remains, so that heating in this case also tends to cause similar Michael addition, which is not preferable.

The urethane prepolymer in the present invention is
After neutralization, as an optional component, for example, a compound having two or more (meth) acryloyl groups, a photopolymerization initiator, an organic or inorganic pigment, a soluble organic dye, an antioxidant, as long as the object of the present invention is not impaired. It is also possible to disperse a compound such as an agent, a plasticizer, and finely divided silica in an aqueous medium together with the prepolymer, and then extend the chain with a polyamine. Compared to adding the above-mentioned additive to the aqueous resin composition after solvent removal, by adding the above-mentioned compound before chain extension, a composition having more excellent dispersibility can be obtained.

As the compound having two or more (meth) acryloyl groups to be added as an optional component, any of generally known polyfunctional (meth) acrylic monomers and oligomers can be applied without any particular problem. The number of (meth) acryloyl group functional groups of the compound is 2 to
A 15-functional one can be applied. As a specific example, in addition to the compound described above as a compound having two or more (meth) acryloyl groups in the section of Michael addition, as a 15-functional compound, a terminal isocyanate group of a hexamethylene diisocyanate cyclic trimer ( A compound obtained by reacting dipentaerythritol pentaacrylate with trifunctional (for example, NK oligo U-15HA manufactured by Shin-Nakamura Chemical Co., Ltd.,
Molecular weight of about 3600) and the like, one of these,
Alternatively, two or more kinds of compounds can be mixed and used.

Examples of the photopolymerization initiator include 2-hydroxy-2-methyl-1-phenylpropan-1-one and 4- (2-hydroxyethoxy) phenyl- (2-
Hydroxy-2-propyl) ketone, (4-benzoylbenzyl) trimethylammonium chloride, 2-
(3-dimethylamino-2-hydroxypropoxy)-
3,4-Dimethyl-9H-thioxanthen-9-one-
A water-affinitive or water-dispersible compound such as methyl chloride is preferred.

The aqueous polyurethane resin composition of the present invention comprises
After chain extension of the urethane prepolymer by the above method,
It is produced by distilling off the solvent used for the reaction by vacuum distillation. As distillation conditions, the heating temperature is 50 ° C or lower,
The degree of vacuum is preferably 5 to 300 torr. At this time, a conventionally known antifoaming agent may be added to the aqueous composition to efficiently perform distillation.

The active energy ray in the present invention is a general term for electromagnetic radiation such as electron beam and ultraviolet ray, electromagnetic wave and the like. Also, when curing by irradiating ultraviolet rays,
If necessary, a photopolymerization initiator that generates radicals by absorption of ultraviolet rays is added, and the addition ratio is 1 to 15 parts by weight of the photopolymerization initiator with respect to 100 parts by weight of the urethane resin (solid content conversion). It is preferably added in the range of parts. As a specific example of the photopolymerization initiator, the same compounds as those mentioned above are used.

[0045]

EXAMPLES The present invention will be described in more detail below by showing Reference Examples, Examples, and Comparative Examples, but the present invention is not limited to these Examples. Also,
In the following, all parts and% are based on weight unless otherwise specified.

Reference Example 1 Kayarad DPHA (manufactured by Nippon Kayaku Co., Ltd., dipentaerythritol hexaacrylate) was placed in a 1-liter four-necked flask equipped with a reflux condenser, a thermometer, and a stirrer. 2 g, 40 g of acetonitrile, and 110 g of ethyl acetate were charged, and this mixture was dissolved with stirring. Next, monoethanolamine (manufactured by Nippon Shokubai Co., Ltd., purity 99.9%) 7.
35 g of acetonitrile 30 g, and ethyl acetate 20 g
The temperature inside the flask is 30 ℃
While cooling with water so as not to exceed the temperature, add dropwise over about 25 minutes,
After completion of dropping, stirring was continued for 15 minutes. The final internal temperature was 27 ° C. At this point, the content liquid was sampled and the following three kinds of quantitative analysis were performed by titration. (1) Quantification of total amino groups: About 6 g was precisely weighed, and 30 ml of tetrahydrofuran was added to dilute and dissolve the solution.
Total amino groups were quantified with 5N hydrochloric acid aqueous solution. (Indicator; bromphenol blue) As a result, all the amino groups were 0.
It was 1204 mol / total amount. (2) Quantification of tertiary amino group; about 15.5 g was precisely weighed, diluted and dissolved in 30 ml of tetrahydrofuran, and further hydrogenated XD
After adding 0.6 g of I and reacting to remove primary and secondary amino groups, the solution was treated in the same manner as in (1) to give 0.5
The tertiary amino group was quantified with N hydrochloric acid aqueous solution. As a result, 3
The amount of primary amino groups was 0.0004 mol / total amount. (3) Quantification of primary amino group: About 2.55 g was precisely weighed, 10 ml of 0.1N salicylaldehyde (pyridine solution) was added to the solution diluted with 50 ml of dry pyridine, and the mixture was gently shaken for about 1 minute. . (1 for salicylaldehyde
It reacts with a primary amino group to form an aldimine and neutralizes it). Then, the excess phenolic hydroxyl group of salicylaldehyde was quantified with 0.1N sodium methoxide (pyridine solution). (Indicator: Phenolphthalein) In addition, a blank test was conducted in the same procedure in parallel.

As a result, the titration amount of 0.1N sodium methoxide was completely the same as that in the blank test, there was virtually no primary amino group, and the monoethanolamine used in the reaction was almost 100% Michael. It was confirmed that it contributed to the addition. From the results of (1) to (3) above, the secondary amino group = all amino groups- (primary amino group + tertiary amino group) [N / total amount] was obtained, and the secondary amino group was 0. It was 1200 mol / total amount. Therefore,
The conversion of primary ethanol monoethanolamine to the target secondary amine by Michael addition to the acryloyl group of dipentaerythritol hexaacrylate was 99.7% based on monoethanolamine.

Reference Example 2 Kayalad DPHA (manufactured by Nippon Kayaku Co., Ltd., above) 74.3 in a 1-liter four-necked flask equipped with a reflux condenser, a thermometer, and a stirrer.
g, 0.23 g of triethylenediamine, and 150 g of methyl ethyl ketone were charged, and this mixture was dissolved with stirring. Next, 1-thioglycerin (Asahi Chemical Co., Ltd.)
Manufactured by 1-thioglycerol, purity 98%) 17.6 g dissolved in methyl ethyl ketone 22 g, while water cooling lightly so that the inner temperature of the flask does not exceed 30 ° C.,
The solution was added dropwise over about 1 hour, and after completion of the addition, stirring was continued for another 30 minutes. At this point, sample the content liquid (about 15 g
The solution diluted with 50 ml of dry pyridine
The residual mercapto group was quantified with 0.1N sodium methoxide (pyridine solvent). (Indicator: Phenolphthalein) As a result, the titer is 0-0.05 ml
Then, it was confirmed that the residual mercapto group was virtually absent, and that 1-thioglycerin contributed to almost 100% of the reaction.

Example 1 Preparation of Prepolymer A Kayarad DPHA was placed in a 3-liter four-necked flask equipped with a reflux condenser, a thermometer, a nitrogen inlet tube, and a stirrer.
360 parts (manufactured by Nippon Kayaku Co., Ltd., above), 124 parts acetonitrile, and 341 parts ethyl acetate were charged and the mixture was dissolved with stirring. Then, a solution prepared by dissolving 22.8 parts of monoethanolamine (manufactured by Nippon Shokubai Co., Ltd., purity 99.9%) in a mixed solvent of 93 parts of acetonitrile and 62 parts of ethyl acetate was used, when the inner temperature of the flask was 30 ° C or higher. The solution was added dropwise over about 25 minutes while gently cooling with water so that the temperature did not become too low. After the completion of the addition, stirring was continued for 15 minutes. next,
378 parts of methyl ethyl ketone, dicyclohexylmethane-4,4′-diisocyanate 451.
4 parts, 2,2-dimethylolpropionic acid 53.9 parts,
PLACCEL L205AL (manufactured by Daicel Chemical Industries, polycaprolactone diol, hydroxyl value 226 mgKOH /
g) 64.2 parts, 2,4-di-t-butylphenol 0.8 parts, and dibutyltin dilaurate 0.8 parts were sequentially charged, heated to 75 ° C. while introducing dry air, and reacted for 3.5 hours. It was The isocyanate group-containing concentration in the obtained solution was 3.58%. To this, 46.2 parts of 2-hydroxypropyl acrylate was added, and the mixture was further reacted for 2 hours (concentration of isocyanate group in solution: 2.52%),
Then, neutralize by adding 40.6 parts of triethylamine,
2024 parts of a urethane prepolymer (P-1) having an isocyanate group content concentration of 2.47% was obtained.

(Examples 2 to 9 Preparation of Prepolymer) In the same manner as in Example 1, urethane prepolymers (P-2 to 9) shown in Tables 1 to 3 below were obtained.

Example 10 Preparation of Prepolymer A 3 liter four-necked flask equipped with a reflux condenser, a thermometer, a nitrogen inlet tube, and a stirrer was placed in Kayarad DPHA.
(Nippon Kayaku Co., Ltd., dipentaerythritol hexaacrylate) 230 parts, triethylenediamine 0.7
Parts and 465 parts of methyl ethyl ketone were charged and the mixture was dissolved with stirring. Next, 1-thioglycerin (1 Asihi Chemical Co., Ltd. 1-thioglycerol, purity 9
(8%) 54.6 parts of methyl ethyl ketone dissolved in 68 parts of the solution was added dropwise over about 1 hour while lightly cooling the flask so that the internal temperature of the flask was 30 ° C. or lower, and stirring was continued for 30 minutes after the completion of the addition. Continued. Then, in this reaction vessel, 465 parts of methyl ethyl ketone, 53.0 parts of 2,2-dimethylolpropionic acid, PLACCEL L205AL
(Daicel Chemical Co., Ltd., polycaprolactone diol, hydroxyl value 226 mgKOH / g) 106.3 parts, Bremmer GLM (NOF CORPORATION, glycerin monomethacrylate, hydroxyl value 678) 35.3 parts, hydroquinone monomethyl ether 0 .8 parts, dibutyltin dilaurate 0.8 parts, and dicyclohexylmethane-4,
518.3 parts of 4'-diisocyanate was charged, heated to 75 ° C while introducing dry air, and reacted for 10 hours. The isocyanate group-containing concentration of the obtained solution was 2.
75%. After further cooling to 40 ° C. or lower, the mixture was allowed to stand overnight and neutralized by adding 40.0 parts of triethylamine to obtain 2018 parts of urethane prepolymer (P-10) having an isocyanate group concentration of 2.49%.

Example 11 Preparation of Prepolymer A urethane prepolymer (P-11) having the composition shown in Table 3 was obtained according to Example 10.

[0053]

[Table 1]

[0054]

[Table 2]

[0055]

[Table 3]

The names of the compounds using the abbreviations in Tables 1 to 3 are as shown below. * 1: DPHA ... Dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.) * 2: D-310 ... Dipentaerythritol pentaacrylate monoalkanoate (manufactured by Nippon Kayaku Co., Ltd.) * 3: A- TMMT..Pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) * 4: FM210, trimethylolpropane triacrylate (manufactured by Nippon Kayaku Co., Ltd.) * 5: NPGDA, neopentyl glycol diacrylate (Nippon Kayaku Kayarad NPGDA) * 6: Hydrogenated MDI / dicyclohexylmethane-4,4 '
-Diisocyanate * 7: hydrogenated XDI / cyclohexane-1, 3 (and 1,
4) -diisocyanate methyl * 8: XDI ... Xylylene diisocyanate * 9: DMPA..2,2-dimethylolpropionic acid * 10: L205AL.polycaprolactone diol (Placcel L205AL, O manufactured by Daicel Chemical Industries, Ltd.)
H value 226 mg KOH / g) * 11: GLM ... Glycerin monomethacrylate (manufactured by NOF CORPORATION, Bremmer GLM, OH value 678)
mgKOH / g) * 12: P-1010 / adipic acid / methylpentadiol polyester diol (Kuraray Co., Ltd., Clapol P-1010, OH value 112 mgKOH / g) * 13: Hydrogenated BPA / hydrogenated bisphenol A * 14: HQME ··· hydroquinone monomethyl ether * 15: DBTDL · dibutyltin dilaurate * 16: HPA: 2-hydroxypropyl acrylate

The residual NCO concentration of each urethane prepolymer obtained in Examples 1 to 11, the obtained amount, and the sample No.
Are shown in Tables 4-6 below.

[0058]

[Table 4]

[0059]

[Table 5]

[0060]

[Table 6]

Example 12 Preparation of Aqueous Resin Composition A prepolymer (P-1) obtained in Example 1 was placed in a 2-liter four-necked flask equipped with a thermometer, a stirrer, and a distillation cooling tube. ), And 33.3 parts of Kayarad DPHA (above) were mixed and dissolved. Next, after adding 400 parts of deionized water and stirring for 2 minutes to disperse in water, 11.4 parts of anhydrous piperazine was dissolved in 255 parts of deionized water while controlling the internal temperature so as not to exceed 30 ° C. The aqueous solution was added over about 5 to 10 minutes, and stirring was continued for another 2 hours at the same temperature to perform chain extension. Then, the contents are heated to 50 ° C., the solvents and a part of water are distilled off under reduced pressure to obtain the desired aqueous polyurethane resin composition (N
-1) was obtained. The nonvolatile content of this composition was 39.6%.

(Examples 13-26 Preparation of Aqueous Resin Composition) The urethane prepolymers were chain-extended in the same manner as in Example 12, and the aqueous polyurethane resin compositions (N -2-15) were obtained.

[0063]

[Table 7]

The names of the compounds using the abbreviations in Table 7 and Tables 8 to 10 described later are as shown below. * 3: A-TMMT ...: * 17: DPCA-30 ...: Caprolactone-modified dipentaerythritol hexaacrylate (Nippon Kayaku Co., Ltd.)
* 18: A-TMM-3..Pentaerythritol triacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) * 19: U-15HA..Hexamethylenediisocyanate cyclic trimer / dipentaerythritol pentaacrylate adduct (new) Nakamura Chemical Co., Ltd.)

[0065]

[Table 8]

[0066]

[Table 9]

[0067]

[Table 10]

Comparative Example 1 A 2-liter four-necked flask equipped with a reflux condenser, a thermometer, a nitrogen inlet tube and a stirrer was placed in a 2-liter four-necked flask containing 500 parts of methyl ethyl ketone and 28.2 parts of 2,2-dimethylolpropionic acid. , PLACCELL
205AL (manufactured by Daicel Chemical Industries, Ltd., polycaprolactone diol, hydroxyl value 226 mgKOH / g) 194.
7 parts, 8.8 parts of trimethylolpropane, 217.5 parts of isophorone diisocyanate, and 0.4 parts of dibutyltin dilaurate were charged, and at 75 ° C. while introducing dry air.
The mixture was heated to room temperature and reacted for 7 hours. The isocyanate group content (solid content conversion) of the obtained product was 2.77%. Next, 50.8 parts of 2-hydroxyethyl acrylate and 0.4 parts of 2,4-di-t-butylphenol were added thereto, and the mixture was reacted at 75 ° C. for 12 hours in the same manner,
A prepolymer having an isocyanate group concentration of 0.80% in the solution and an acid value (solid content conversion) of 23.6 mgKOH / g was obtained.
To this, 21.1 parts of triethylamine was added for neutralization,
After further cooling to 30 ° C. or lower, 489 parts of deionized water was added to this prepolymer and stirred for 10 minutes to disperse in water. Then, while controlling the internal temperature so as not to exceed 30 ° C., isophoronediamine 15 An aqueous solution of 0.8 parts dissolved in deionized water was added over 10 minutes, and stirring was continued for another 1.5 hours to obtain an aqueous urethane resin. Next, the contents are heated to 50 ° C.
The mixture was heated up to, and methyl ethyl ketone and a part of water were distilled off under reduced pressure to obtain a desired aqueous polyurethane resin composition (C-1). The nonvolatile content of this composition is 32.
4%.

(Comparative Example 2) Kayarad FM210 (Nippon Kayaku Co., Ltd.) was added to 200 parts of C-1 obtained in Comparative Example 1.
Manufactured by trimethylolpropane triacrylate) 13
And 0.6 part of Emulgen 810 (manufactured by Kao Corporation, polyoxyethylene octyl phenyl ether) were added, and the mixture was vigorously stirred for 5 minutes with a homogenizer to obtain an aqueous polyurethane resin composition (C-2).

(Comparative Example 3) 275.4 parts of isophorone diisocyanate was placed in a 3-liter four-necked flask equipped with a reflux condenser, a thermometer, a nitrogen inlet tube, and a stirrer.
5,2-Dimethylolpropionic acid 52.8 parts, PLA
CCEL L205AL (manufactured by Daicel Chemical Industries, polycaprolactone diol, hydroxyl value 226 mgKOH / g) 1
02.7 parts, Bremmer GLM (manufactured by NOF Corporation, glycerin monomethacrylate) 33 parts, trimethylolpropane 11 parts, 2,4-di-t-butylphenol 0.5 part, dibutyltin dilaurate 0.5 part Preparation,
While introducing dry air, the mixture was heated to 75 ° C. and reacted for 7 hours. The prepolymer solution thus obtained had an isocyanate group concentration of 2.88%. To this, 75.3 parts of 2-hydroxypropyl acrylate was added and further reacted at 75 ° C. for 15 hours to give an isocyanate group content of 0.20%,
A polyurethane resin having an acid value (in terms of solid content) of 40.1 mg KOH / g was obtained. Next, this resin is treated with triethylamine 4
After neutralizing with 1.8 parts, add 1280 parts of deionized water to obtain 10 parts.
After stirring for 1 minute and dissolving in water, the internal temperature is heated to 50 ° C., the methyl ethyl ketone and a part of water are distilled off under reduced pressure, and the desired aqueous polyurethane resin (C-3) 7
40 parts were obtained. The nonvolatile content of this composition was 29.0%.

The following measurements and evaluations were carried out on the aqueous polyurethane resin compositions obtained in Examples 12 to 26 and Comparative Examples 1 to 3. (1) Change in viscosity of composition over time The viscosity of the above aqueous polyurethane resin composition at 25 ° C. was measured by the Gardner-Holt method. (2) Coating film test The above aqueous polyurethane resin composition was deionized water at 25%.
After the adjustment, the coated decorative paper on which wood grain was printed was applied using a drawdown rod # 7 and dried with hot air at 130 ° C. for 30 seconds to prepare each test sample having an application amount of about 4 g / m ² . Then, the following evaluation tests were performed on each sample.

Blocking resistance: A piece of paper containing several uncured samples with a size of 5 cm × 5 cm was stacked, and a load equivalent to 4 kg / m ² was applied onto it, and then 6
After storing at 0 ° C. for 20 hours, the temperature was returned to room temperature, and the blocking state of the sample was evaluated.

Blocking resistance evaluation criteria: 5 No blocking at all 4 When a paper piece is peeled off, there is a slight noise 3 When a paper piece is peeled off, there is a strong resistance 2 When a paper piece is peeled off, a part of the printed part is transferred 1 Peeling off None The above sample was irradiated with an electron beam in an amount equivalent to 30 KGy and cured under the condition of 165 kV / 20 mA using an electron curtain irradiator manufactured by US ESI Co., Ltd.
The physical properties of the cured sample were evaluated as follows.

Curability: The degree of stickiness was evaluated by touching with a finger according to the following criteria. ◯: No stickiness Δ: Slightly sticky ×: Significantly sticky Solvent resistance: Rubbing the surface of the cured sample with a cotton swab soaked with MEK, and measuring the number of rubbing until the underlying print is damaged. The numerical values in Tables 11 to 13 are shown as an average value of 5 times. (The higher the value, the better)

[0075]

[Table 11]

[0076]

[Table 12]

(Examples 27 to 30 and Comparative Examples 4 to 5) The aqueous polyurethane resin compositions were adjusted to 25% with deionized water, and the following components were added to each resin and mixed with a homogenizer. The thing is applied to the construction material decorative paper printed with wood grain using the draw down rod # 7, at 80 ° C,
It was dried with hot air for 60 seconds to prepare each test sample having a coating amount of about 4 g / m ² . Next, each of the above samples was irradiated with ultraviolet rays of 110 mJ / cm ² with a metal halide lamp, and a solvent resistance test by MEK similar to the above was carried out. -Aqueous polyurethane resin composition (nonvolatile content 25%) 100 parts-Darocur 1173 2.0 parts (2-hydroxy-2-methyl-1-phenylpropan-1-one manufactured by Ciba-Geigy) -Emulgen 810 0.3 parts ( Kao Corporation, polyoxyethylene octyl phenyl ether)

[0078]

[Table 13]

[0079]

INDUSTRIAL APPLICABILITY As described above, the active energy ray-curable aqueous polyurethane resin composition using the urethane prepolymer of the present invention has a relatively small change in viscosity as an aqueous resin, and has an anti-blocking property of an uncured coating film. , Curability, and solvent resistance after curing are combined, it is superior to the aqueous polyurethane resin composition using the conventional urethane prepolymer, and in particular, paints, coating agents, adhesives, printing inks, etc. It can be suitably used for the purpose.

Claims (10)

[Claims] 1. A product obtained by Michael-adding a hydroxy compound having active hydrogen to a double bond of a compound having (a) two or more (meth) acryloyl groups (abbreviated as Michael adduct), (b) ) A urethane prepolymer which is obtained by reacting a polyhydroxy compound having an acidic group and (c) a polyisocyanate compound as essential components. 2. The urethane prepolymer according to claim 1, wherein the compound having two or more (meth) acryloyl groups is one or more compounds selected from difunctional to hexafunctional (meth) acrylates. 3. A hydroxy compound having active hydrogen,
A hydroxy compound having a primary amino group, and / or 1
The urethane prepolymer according to claim 1, which is a hydroxy compound having a graded mercapto group. 4. An aqueous polyurethane resin composition comprising a urethane prepolymer having a (meth) acryloyl group, an acidic group, and a terminal isocyanate group, neutralized, dispersed in an aqueous medium, and then chain-extended with a polyamine. The urethane prepolymer has two (a) (meth) acryloyl groups.
A product obtained by Michael-adding a hydroxy compound having active hydrogen to a double bond of a compound having two or more compounds (abbreviated as Michael adduct), (b) polyhydroxy compound having an acidic group, and (c) polyisocyanate An active energy ray-curable aqueous polyurethane resin composition, which is obtained by reacting a compound as an essential component. 5. The active energy ray curing according to claim 4, wherein the compound having two or more (meth) acryloyl groups is one or more compounds selected from difunctional to hexafunctional (meth) acrylates. Molded aqueous polyurethane resin composition. 6. A hydroxy compound having active hydrogen,
A hydroxy compound having a primary amino group, and / or 1
The active energy ray-curable aqueous polyurethane resin composition according to claim 4, which is a hydroxy compound having a graded mercapto group. 7. A product obtained by Michael-adding a hydroxy compound having active hydrogen to a double bond of a compound having two or more (meth) acryloyl groups as a first step, and the product as a second step. (Preferred as a Michael adduct), a polyhydroxy compound having an acidic group and a polyisocyanate compound as essential components, and other polyhydroxy compounds as optional components are added and reacted. Manufacturing method. 8. The production of the urethane prepolymer according to claim 7, wherein the compound having two or more (meth) acryloyl groups is one or more compounds selected from difunctional to hexafunctional (meth) acrylates. Method. 9. A hydroxy compound having active hydrogen,
A hydroxy compound having a primary amino group, and / or 1
The method for producing a urethane prepolymer according to claim 7, which is a hydroxy compound having a graded mercapto group. 10. After neutralizing the urethane prepolymer according to claim 1, as an optional component, a compound having two or more (meth) acryloyl groups, a photopolymerization initiator, an organic or inorganic pigment, a soluble organic dye, and an oxidation. A method for producing an active energy ray-curable aqueous polyurethane resin composition, which comprises dispersing a compound such as an inhibitor, a plasticizer, and finely divided silica in an aqueous medium together with the prepolymer, and then chain-extending with a polyamine. .