JP2000017030A - Active energy ray curable aqueous resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an active energy ray curable aqueous resin composition capable of efficiently introducing (meth)acryloyl groups into resin skeletons, free from blocking even in uncured coated films and, in addition, possessing excellent properties in curability, solvent resistance and abrasion resistance. SOLUTION: A modified resin obtained by reacting (a) a Michael addition product of a compound having one primary amino group in the molecule to the double bond of a compound having two or more (meth)acryloyl groups with (b) a styrene/maleic anhydride copolymer as the essential components is neutralized, and then, dispersed into an aqueous medium and, if necessary, further chain-extended with a polyamine to obtain an active energy ray curable aqueous resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active energy ray-curable aqueous resin composition using a novel and useful modified styrene / maleic anhydride resin.

[0002]

2. Description of the Related Art In recent years, problems of environmental pollution have been pointed out.
From the viewpoint of health and safety, it is increasingly required to further improve the working environment, and there is a demand for technical development and production in consideration of reducing the usage of organic solvents as much as possible. In the fields of paints, coatings, adhesives, and printing inks, resins applied to such applications often use a large amount of organic solvents in the past. The shift to so-called water-free or solvent-free use, which is not just used, is an immediate technical problem. In particular, a water-based resin is considered to have a large practical advantage because the residue at the time of coating can be diluted and washed with water.

On the other hand, in the fields of paints, coatings, adhesives, printing inks and the like, aqueous resins which can be cured by active energy rays such as electron beams and ultraviolet rays, and compositions containing them are widely applied. For example, polyurethane (meth) acrylate and polyester (meth) acrylate having a (meth) acryloyl group suspended at the side chain and / or terminal of each resin skeleton of urethane resin or polyester resin, respectively. However, in both cases, the Tg of the modified resin is not so high in many cases. Particularly, in the case where a step of winding uncured resin after coating is required, there is a disadvantage that it is not easy to apply because it tends to cause blocking. In addition to this, a resin in which a (meth) acryloyl group is suspended in a side chain such as a (meth) acrylic resin or a styrene / (meth) acrylic resin is often examined for application to the above-mentioned applications. However, in this case, in terms of the synthesis technology for suspending the (meth) acryloyl group,
Furthermore, there are considerable restrictions on the density of the suspended (meth) acryloyl groups and the like, and sufficient performance has not been achieved. For example, in the case of a reaction in which glycidyl methacrylate (GMA) is introduced into a backbone polymer in which (meth) acrylic acid is incorporated in the skeleton, it is usually necessary to perform the reaction in a low molecular alcohol solvent system such as ethanol, and the introduction efficiency is not always good. . In Japanese Patent Application Laid-Open No. 8-113627, an acrylic latex containing m-TMI (m-isopropenyl-α, α-dimethylbenzyl isocyanate) in a monomer composition is used for a (meth) acrylate containing active hydrogen (for example, HEA,
Aqueous resin surface-modified with HEMA, etc., is disclosed, but this is also very slow and inefficient.

Japanese Patent Publication No. 4-69381 discloses a photopolymerizable photosensitive resin (for example, an acid anhydride of styrene / maleic anhydride resin) in which a polyfunctional ethylenically unsaturated group is suspended from the resin skeleton via an ester bond. Photosensitive resin with addition reaction of polyfunctional acrylate having hydroxyl group in the molecule.
In this case, although the pendant density of the (meth) acryloyl group may be considerably increased by selecting acrylate, the pendant density originally having hydroxyl groups in the acid anhydride unit incorporated in the resin is disclosed. The reaction for adding the functional acrylate is very slow in terms of rate, and is not an efficient reaction as a means for suspending the (meth) acryloyl group. At present, there are still issues from this viewpoint. That is, none of these prior arts has a satisfactory balance of production efficiency, coating film blocking properties, solvent resistance and the like.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to efficiently introduce a (meth) acryloyl group into a resin skeleton, prevent a coating film from blocking, and obtain a curable resin.
An object of the present invention is to provide a novel active energy ray-curable aqueous resin composition having both performances such as solvent resistance and abrasion resistance.

[0006]

Means for Solving the Problems As a result of intensive studies in view of the above situation, the present inventor has found the following aqueous resin composition in order to achieve the above object, and has completed the present invention. . That is, the composition of the present invention comprises (a) a product (Michael) obtained by Michael-adding a compound having one primary amino group to the double bond of a compound having two or more (meth) acryloyl groups. (B) an active energy obtained by neutralizing a modified resin obtained by reacting a styrene / maleic anhydride copolymer as an essential component and then dispersing the modified resin in an aqueous medium. It is a line-curable aqueous resin composition. Further, the composition of the present invention is characterized in that the active energy ray-curable aqueous resin composition dispersed in an aqueous medium is further subjected to chain extension with a polyamine. It is.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The water-based resin of the present invention, when synthesizing the above-mentioned Michael adduct which is an essential component thereof, uses a polyfunctional (meth) acrylate compound having a higher number of (meth) acryloyl functional groups in a polyfunctional (meth) acrylate compound. Since the (meth) acryloyl group can be suspended in the resin side chain in a block shape, the suspension density of the (meth) acryloyl group can be increased accordingly. Accordingly, the active energy ray-curable aqueous resin composition of the present invention, which is obtained by dispersing the modified resin in an aqueous medium after neutralization and, if necessary, extending the chain with a polyamine, comprises a conventionally known (meth) acryloyl group. Excellent cross-linkability and curability compared to water-based resins, solvent resistance, abrasion resistance, and furthermore, based on styrene / maleic anhydride resin, the blocking resistance of uncured coating film It also has excellent characteristics in terms of surface.

Hereinafter, the present invention will be described in detail. In the following text, a (meth) acryloyl group refers to both an acryloyl group and a methacryloyl group.

In producing the aqueous resin of the present invention in which a polyfunctional (meth) acrylate is suspended in a side chain, a method for introducing a (meth) acryloyl group into a side chain is to have two or more (meth) acryloyl groups. A product obtained by Michael addition of a compound having one primary amino group to a double bond of the compound (referred to as Michael adduct) is used as an essential component. The "Michael addition reaction" used as a reaction for producing the adduct is described in Organic React.
ion Vol. 5, p. 79, Method de
r Organischen Chemie Vol.
9, page 120, Vol. Reaction examples are described on pages 11/1 and 277. According to these, in the case of primary and secondary amino groups, mercapto groups, phenolic hydroxyl groups, β-diketones, or acetoacetyl groups, non-catalytic systems,
It is also described that, if necessary, a so-called Michael addition proceeds by a nucleophilic ion reaction to a double bond such as an α, β-unsaturated carboxylic acid ester or an α, β-unsaturated nitrile in a catalyst system. ing.

For example, in the case of a primary amino group, Michael is easily added to an α, β-unsaturated carboxylic acid or an ester thereof, furthermore, acrylonitrile or the like at room temperature in a noncatalytic system at room temperature to convert a secondary amine. Generate.

Therefore, the Michael adduct according to the present invention is a compound in which one compound having one primary amino group has a nucleophilic property in a part of the (meth) acryloyl group of a compound having two or more (meth) acryloyl groups. A compound in which a primary amino group is added by a reactive ionic reaction and the remaining (meth) acryloyl group is suspended through a bond with a secondary amine formed as a result.

In this case, the resulting secondary amine has much lower reactivity with the (meth) acryloyl group than the primary amine, and therefore, the (meth) acryloyl compound having one active hydrogen of the secondary amine Contributes to the addition reaction with the acid anhydride unit of the styrene / maleic anhydride resin.

As the compound having one primary amino group in the present invention, the Michael adduct is used in the case where a secondary amino group, a hydroxyl group or a mercapto group is also contained as another functional group in the same molecule. When hanging from the resin,
Excluded from the subject because it tends to gel. Specific examples include monoalkylamines such as ethylamine, isopropylamine and n-butylamine, alicyclic monoamines such as cyclohexylamine, other benzylamines, γ-
Examples include aminopropyltrimethoxysilane, β-methoxyethylamine, allylamine and the like. Among them, benzylamine is particularly preferred.

(Meth) used in the Michael addition reaction with the compound having one primary amino group in the present invention.
As the compound having two or more acryloyl groups, any of generally known polyfunctional (meth) acrylic monomers and oligomers can be applied without any problem. The number of (meth) acryloyl functional groups in the compound is preferably 2 to 6 functional groups, and is not particularly limited.

Specific examples include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, and polyethylene glycol di (meth) acrylate.
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. 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, ε
-Caprolactone-modified dipentaerythritol hexa (meth) acrylate, phosphazene hexamethacrylate, polyester (meth) acrylate (eg, Evecryl EB1830 / manufactured by Daicel UCB Co., Ltd.) and the like, and one of the compounds exemplified above or 2 More than one species can be used.

In the present invention, the ratio of the compound having one primary amino group to the compound having two or more (meth) acryloyl groups is calculated as: As a compound having two or more (meth) acryloyl groups, 0.6 mol or more, and more preferably 0.8 mol to
A range of 2.0 moles is more preferred. If this value exceeds 2.0 mol, the proportion of the (meth) acryloyl compound not involved in Michael addition increases accordingly, but there is no particular problem in the production of the aqueous resin of the present invention. Also, this value
If the amount is less than 0.6 mol, the number of addition reactions occurring in the same molecule becomes too large, and gelation easily occurs at the stage of producing the Michael adduct.

The compound having one primary amino group in the present invention can be used alone or as a mixture thereof, and the above molar ratio is applied in any case. The molar ratio is such that the (meth) acryloyl group is 2
This applies regardless of the number of functional groups in the compound having two or more compounds.

The Michael adduct, which is an essential component of the aqueous resin in the present invention, is obtained by dissolving a predetermined amount of a compound having two or more (meth) acryloyl groups in an organic solvent and stirring the solution with stirring. It is synthesized by dropping a solvent diluent of the compound having one primary amino group. The reaction temperature at this time is 40 ° C. or less, preferably 10 ° C.
It is better to carry out at ~ 30 ° C. The dropping time is 10
It is good to carry out for 120 to 120 minutes, preferably 20 to 40 minutes. After completion of the dropwise addition, stirring is continued for another 3 to 5 hours, depending on the amount of the solvent in the content.

The solvent used in this case may be a compound having two or more (meth) acryloyl groups and a primary amino group having one or more (meth) acryloyl groups.
There is no particular limitation as long as it is compatible with any of the compound having the same and the styrene / maleic anhydride resin and is inert to the acid anhydride group.

Specific examples include ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; aprotic amides such as N-methylpyrrolidone, dimethylformamide and dimethylacetamide; cellosolve esters such as methyl cellosolve acetate; ethyl acetate; Examples thereof include esters such as butyl acetate, and nitriles such as acetonitrile and propionitrile.
Species or a mixture of two or more species can be used. Among them, ethyl acetate is particularly preferably used.

The constitutional molar ratio of styrene / maleic anhydride in the styrene / maleic anhydride resin used in the production of the aqueous resin in the present invention is not particularly limited.
/ 1 is most preferred.

The weight average molecular weight of the styrene / maleic anhydride resin used in the production of the aqueous resin in the present invention is preferably 6000 or less, more preferably 1500 to 3000. If the molecular weight exceeds 6,000, it tends to be difficult to disperse the modified resin in water.

The amount of the styrene / maleic anhydride resin used in the production of the aqueous resin in the present invention is defined as follows by the number of moles of the compound having one primary amino group.

(S × W) ÷ (2 × 56100) ÷ (A ÷ m)> 1.0

However, the above symbols represent the following. S: Acid value of styrene / maleic anhydride resin [mgK
OH / g, in terms of solid content] W: Addition amount of styrene / maleic anhydride resin [g] A: Addition amount of compound having one primary amino group [g] m: Compound having one primary amino group Further, it is more preferable that the above ratio (the left side of the formula) is 1.6 to 2.1.

The reaction temperature for introducing the Michael adduct into the styrene / maleic anhydride resin in the present invention is preferably 10 to 90 ° C., more preferably 40 to 60 ° C. If the temperature is lower than 10 ° C., the reactivity of the Michael adduct is low. If the temperature exceeds 90 ° C., the thermal reaction of the (meth) acryloyl group is apt to occur, and the thermal stability of the reaction solution is deteriorated.
Further, after completion of the above introduction reaction, it is possible to further introduce a compound having one active hydrogen such as a hydroxyl group or an amino group into a part of the acid anhydride groups remaining in the resin molecule without impairing the purpose of the present invention. Acceptable in the range.

After the introduction reaction of the Michael adduct into the styrene / maleic anhydride resin in the present invention is completed, as a neutralizing agent for the carboxyl group that develops along with the reaction,
An organic basic compound is used. Specific examples include triethylamine, tri-n-butylamine, triallylamine, N, N-dimethylethanolamine, N, N-diethylethanolamine, N-methyldiethanolamine, triethanolamine, Ammonia and the like.

The modified resin obtained by introducing a Michael adduct into the styrene / maleic anhydride copolymer of the present invention can be neutralized, dispersed in an aqueous medium, and further subjected to chain extension with a polyamine if necessary. A primary or secondary polyamine is used as a chain extender at that time. Specific examples include primary diamines such as ethylenediamine, isophoronediamine, xylylenediamine, norbornanediaminomethyl, diethylenetriamine, and 2-aminoethylethanolamine, or primary amine-containing polyamines, piperazine, and 2-methylpiperazine. Secondary diamines are exemplified. Among them, 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.

At this time, the modified resin in the present invention is further neutralized, after neutralization, within a range that does not impair the purpose of the present invention.
As an optional component, for example, a (meth) acryloyl group
Compounds having at least one compound, a thermal polymerization inhibitor, a photopolymerization initiator, an organic or inorganic pigment, a soluble organic dye, an antioxidant, a plasticizer, and a compound such as finely divided silica are dispersed in an aqueous medium together with the modified resin in advance. After that, the chain can be extended with a polyamine. Compared to the case where the above-mentioned additive is added to the aqueous resin composition after removing the solvent, a composition having more excellent dispersibility can be obtained by adding the above-mentioned compound before the chain elongation.

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 used without any particular problem. The number of (meth) acryloyl group functional groups of the compound is 2 to
Hexafunctional ones can be applied. Specific examples include the compounds described above as compounds having two or more (meth) acryloyl groups in the description of the Michael adduct.

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-soluble or water-dispersible compound such as methyl chloride is preferred.

The water-based resin of the present invention is produced by distilling off the solvent used in the reaction by distillation under reduced pressure as the final step after the above steps. As the distillation conditions, the heating temperature is 50 ° C. or less, and the degree of vacuum is 5 to 300 tons.
It is preferable to carry out at rr. Further, at this time, a conventionally known antifoaming agent can be added to the aqueous composition to perform efficient distillation.

After the water-based resin of the present invention has been produced through all the above-mentioned steps, as an optional component, for example, a compound having two or more (meth) acryloyl groups, a thermal polymerization inhibitor, a photopolymerization initiator, an organic Alternatively, a compound such as an inorganic pigment, a soluble organic dye, an antioxidant, a plasticizer, and finely divided silica may be added later to be used as an aqueous resin composition.

The term "active energy ray" as used in the present invention is a general term for electromagnetic radiation and electromagnetic waves such as electron beams and ultraviolet rays. Also, when curing by irradiating ultraviolet rays,
If necessary, a photopolymerization initiator that generates radicals by absorbing ultraviolet light is added. The addition ratio of the photopolymerization initiator is 1 to 15 parts by weight based on 100 parts by weight of the aqueous resin (solid content). Parts, more preferably 3 to 5 parts by weight.

[0035]

EXAMPLES The present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples. In the following, all parts and percentages are by weight unless otherwise specified.

(Synthesis Example 1) D was placed in a 1-liter four-necked flask equipped with a reflux condenser, a thermometer, and a stirrer.
100.0 g of PHA (manufactured by Nippon Kayaku Co., Ltd., dipentaerythritol hexaacrylate) and ethyl acetate 10
0.0 g was charged and the mixture was dissolved with stirring. Next, 11.1 g of benzylamine was added to ethyl acetate 1
The solution dissolved in 5.0 g was added dropwise over about 25 minutes while cooling with water so that the internal temperature of the flask did not exceed 30 ° C. After completion of the addition, the mixture was further stirred for 5 hours to synthesize a Michael adduct. did. Then, GSM-151 (styrene / maleic anhydride (1/1) resin, manufactured by Gifu Shellac Co., Ltd.)
After adding a solution in which 9.5 g was previously dissolved in 74.3 g of ethyl acetate, the content was heated to 60 ° C., and stirring was continued at the same temperature for 3 hours. At this time, as a result of analysis, almost no residual amine was detected, and it was confirmed that the Michael adduct was almost completely introduced. After the completion of the reaction, the content is kept at
The solution was cooled with water until neutralized with 10.5 g of triethylamine, and 0.25 g of hydroquinone monomethyl ether was further dissolved. Then, after adding 515 g of deionized water and emulsifying and dispersing in water, 4.0 g of piperazine was further added to deionized water 2.
A solution previously dissolved in 8.5 g was added and stirring was continued at room temperature for 2.5 hours. Finally, the solvent (ethyl acetate) and some water were distilled off under reduced pressure to give a solid concentration of 32.9%.
Thus, an aqueous resin (A-1) was obtained.

(Synthesis Examples 2 to 4)
The aqueous resins (A-2 to 4) shown in Tables 1 and 2 below were obtained.

[0038]

[Table 1] (Michael adduct introduction reaction conditions)

[0039]

[Table 2] (Aqueous condition)

The abbreviations in the above table represent the following. * 1: DPHA; dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.) * 2: EB1830; Ebecryl EB1830 (manufactured by Daicel UCB, 6-functional polyester acrylate) * 3: GSM-151; styrene / maleic anhydride (1/1) resin (weight average molecular weight about 1500, manufactured by Gifu Shellac) * 4: GSM-301; styrene / maleic anhydride (1/1) resin (weight average molecular weight about 3000; Gifu Shellac Co., Ltd.) * 5: Based on charged primary amine (mol%) * 6: Hydroquinone monomethyl ether

(Synthesis Example 5) D was placed in a 1-liter four-necked flask equipped with a reflux condenser, a thermometer, and a stirrer.
100.0 g of PHA (manufactured by Nippon Kayaku Co., Ltd., dipentaerythritol hexaacrylate) and ethyl acetate 10
0.0 g was charged and the mixture was dissolved with stirring. Next, 11.1 g of benzylamine was added to ethyl acetate 1
The solution dissolved in 5.0 g was added dropwise over about 25 minutes while cooling with water so that the internal temperature of the flask did not exceed 30 ° C. After completion of the addition, the mixture was further stirred for 5 hours to synthesize a Michael adduct. did. Then, GSM-151 (styrene / maleic anhydride (1/1) resin, manufactured by Gifu Shellac Co., Ltd.)
After adding a solution in which 9.5 g was previously dissolved in 74.3 g of ethyl acetate, the content was heated to 60 ° C., and stirring was continued at the same temperature for 3 hours. At this time, as a result of analysis, almost no residual amine was detected, and it was confirmed that the Michael adduct was almost completely introduced. Then, 36.0 methanol
g and 0.16 g of trimethylbenzylammonium chloride were added, and stirring was continued at 60 ° C. for 4 hours. After the completion of the reaction, the content was cooled with water to 30 ° C., neutralized with 21.0 g of triethylamine, and further dissolved with 0.25 g of hydroquinone monomethyl ether. Next, 410 g of deionized water was added to disperse the contents in water, and finally, the solvent (ethyl acetate and methanol) and some water were distilled off under reduced pressure to obtain an aqueous solution having a solids concentration of 30.5%. Resin (A
-5) was obtained.

(Comparative Synthesis Example 1) 82.0 g of GSM-151 (above) and 123.0 g of ethyl acetate were charged into a 1-liter four-necked flask equipped with a reflux condenser, a thermometer, and a stirrer. After the resin was completely dissolved at room temperature with stirring, 19.9 g of β-hydroxyethyl acrylate was added to the solution. The content was heated to 60 ° C., and stirring was continued at the same temperature for 8 hours to complete the reaction. Next, the content was cooled with water to 30 ° C., and triethylamine 1
After neutralization with 7.4 g, 0.25 g of hydroquinone monomethyl ether was further dissolved. Next, 320 g of deionized water
And emulsified and dispersed in water, and then piperazine 6.
A solution of 65 g previously dissolved in 42.0 g of deionized water was added and stirring was continued at room temperature for 2.5 hours. Finally, the solvent (ethyl acetate) and some water were distilled off under reduced pressure to obtain an aqueous resin (B-1) having a solid content of 25.9%.

(Comparative Synthesis Example 2) The reaction was carried out in exactly the same procedure as in Comparative Synthesis Example 1 except that GSM-301 (described above) was used instead of GSM-151, and the solid content concentration was 25.4.
% Of an aqueous resin (B-2).

(Examples 1 to 5 and Comparative Examples 1 and 2) Aqueous resins (A-1 to 5 and B-1 to 2) obtained in Synthesis Examples 1 to 5 and Comparative Synthesis Examples 1 and 2 About 4.0%
(Vs. resin solids) considerable amount of photoinitiator (Darocu
r 1173) was previously dissolved in 6 times the amount of methanol and blended, and the viscosity of the blended solution was further reduced to 13 to 13 with Zahn Cup # 4.
A coating solution was prepared by diluting with deionized water so as to obtain 14 seconds (25 ° C.). Next, the coating liquid was applied using a draw-down rod # 12 to a base material on which the wood-grained building material decorative paper was previously adhered to a 0.7 mm-thick backing paper.
A test sample having a coating amount of about 6 g / m ² was prepared by drying with hot air at 30 ° C. for 30 seconds, and the following evaluation was performed.

Blocking resistance test; 10 cm × 1
A stack of paper sheets including several uncured samples of 0 cm in size is stacked, and a load of 4 kg / m ^{2 is} further applied.
After storage at 20 ° C. for 20 hours, the temperature was returned to room temperature, and the blocking state of the sample was evaluated. The blocking resistance evaluation criteria are shown below. : No blocking at all △: Resistance when peeling paper pieces ×: Cannot be peeled

The above-mentioned coated sample was irradiated with an equivalent amount of 200 mJ / cm ² using a 120 W / cm high-pressure mercury lamp and cured, and the cured sample was evaluated for the following physical properties.

Curing test: The degree of stickiness was evaluated by finger touch according to the following criteria. ○: no stickiness △: slightly sticky ×: considerably sticky

Solvent resistance test: The surface of the cured sample was rubbed with a cotton swab impregnated with MEK, and the number of rubbings until the printing of the base was damaged was measured.

Abrasion resistance test (JAS abrasion C test);
A UV-cured sample having a size of 10 cm × 10 cm is attached to a tapered abrasion tester using a soft abrasion wheel to perform a test, and the abrasion state after 200 rotations is evaluated according to the following criteria. ○ Slight wear △ Significant wear × Intense wear

The above evaluation results are shown in Table 3 below.

[0051]

[Table 3]

(Examples 6 to 10 and Comparative Examples 3 and 4) The viscosities of the aqueous resins (A-1 to 5 and B-1 to 2) were reduced to 13 to 14 seconds (25 ° C.) by Zahn Cup # 4. Thus, a coating solution was prepared by diluting with deionized water. Next, the coating liquid was applied using a drawdown rod # 12 to a base material in which wood decorative paper, which had been subjected to wood grain printing in the same manner as described above, was previously attached to a 0.7 mm-thick backing paper. The sample was dried with hot air for 2 seconds to prepare a test sample having a coating amount of about 6 g / m ² . Next, using an electron beam irradiation device made by ESI, USA, an electron beam was irradiated under a condition of 165 kV / 20 mA with an amount equivalent to 30 KGy of the electron beam to be cured, and then the same physical properties were evaluated for the cured sample. Table 4 shows the results.

[0053]

[Table 4]

[0054]

As described above, in the active energy ray-curable aqueous resin composition of the present invention, a (meth) acryloyl group can be efficiently introduced into the resin skeleton in the production process, and the resistance of the uncured coating film can be improved. Blocking properties, curability, solvent resistance after curing, and excellent in having both abrasion resistance, especially,
It can be suitably used for applications such as paints, coatings, adhesives, and printing inks.

Claims (2)

[Claims] 1. A product obtained by Michael-adding a compound having one primary amino group in a molecule to a double bond of a compound having two or more (meth) acryloyl groups (a Michael adduct) Abbreviated) and (b) a modified resin obtained by reacting a styrene / maleic anhydride copolymer as an essential component, after neutralization, and then dispersed in an aqueous medium. -Type aqueous resin composition. 2. The active energy ray-curable aqueous resin according to claim 1, wherein the active energy ray-curable aqueous resin composition is dispersed in an aqueous medium and then chain-extended with a polyamine. Composition.