JP2016044286A - Urethane (meth) acrylate and active energy ray-curable composition comprising the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a urethane (meth) acrylate monomer that can provide a curable composition having improved curability with respect to active energy rays and also excellent sludge suppression performance and anti-foaming performance.SOLUTION: A urethane (meth) acrylate is obtained by a reaction of organic polyisocyanate (a), (meth) acrylate having one hydroxy group in the molecule (b), and (poly) oxyalkylene arylphenyl ether (c).SELECTED DRAWING: None

Description

  The present invention relates to a urethane (meth) acrylate monomer, and more particularly to a urethane (meth) acrylate monomer that improves curability against active energy rays and is excellent in sludge suppression ability and foam suppression.

  Urethane (meth) acrylate is cured by active energy rays, and the resulting cured product has excellent flexibility and adhesiveness, so various optical members, electrical / electronic members, sealing materials, adhesives, paper, plastics, etc. Widely used as a coating agent.

  In recent years, studies on the use of aqueous systems for active energy ray-curable compositions have been underway in these applications due to environmental impacts and safety reasons. To date, (1) an acrylic ester containing at least one hydroxyl group in the molecule, (2) an organic polyisocyanate, and (3) a polyethylene glycol containing at least one hydroxyl group have been obtained. Various urethane (meth) acrylates and emulsion-type active energy ray-curable compositions in which these are dispersed in water are disclosed (Patent Documents 1 to 3).

JP-A-6-287260 JP-A-9-328525 JP 2003-40955 A

As described above, water-based urethane (meth) acrylate has been promoted, and various curable materials have been proposed. However, in these materials, further improvement in curability against active energy rays is required. As a method for improving the curability, there is a method of increasing the blending amount of the photoinitiator in the composition. However, this method has a problem that a water-based curable material leads to sludge generation, causing coating defects and clogging of the coating machine.
On the other hand, the use of polyethylene glycols containing one hydroxyl group is said to have the effect of enhancing the dispersibility of urethane (meth) acrylate. However, with urethane (meth) acrylates that have been proposed so far, it is difficult to achieve compatibility with various performances such as curability, sludge suppression, and antifoaming properties, and urethane (meth) acrylates that satisfy all these performances. There was room for consideration.

  As described above, the present invention has been made in view of the above-described problems, and can improve the curability for active energy rays and can provide a curable composition excellent in sludge suppression ability and foam suppression ability. It is an object to provide a (meth) acrylate monomer.

  As a result of investigations by the present inventors, by adopting (poly) oxyalkylene aryl phenyl ether as a component constituting urethane (meth) acrylate, the obtained urethane (meth) acrylate has curability to active energy rays. It was found that not only the improvement but also the generation of sludge and foaming can be suppressed, and the present invention has been completed.

That is, the present invention relates to urethane obtained by reacting organic polyisocyanate (a) with (meth) acrylate (b) having one hydroxy group in the molecule and (poly) oxyalkylene arylphenyl ether (c). It is intended for (meth) acrylate.
Among them, the urethane (meth) acrylate of the present invention has a molar ratio of (b) component and (c) component to the organic polyisocyanate (a) (b) :( c) = 99: 1 to 50:50. It is preferable that they are reacted at a ratio.

  Moreover, this invention also makes object the active energy ray curable composition containing the said urethane (meth) acrylate (A) and a photoinitiator (B).

The urethane (meth) acrylate of the present invention can improve the curability for active energy rays, and can provide an active energy ray-curable composition that is excellent in sludge suppression ability and foam suppression.
Moreover, the active energy ray-curable composition of the present invention can form a cured film having excellent curability. Furthermore, the composition has a small sludge generation amount and excellent antifoaming properties, that is, not only excellent stability over time, but also suppresses defects such as coating defects and clogging when using a coating machine, etc. can do.

The urethane (meth) acrylate of the present invention is obtained by reacting organic polyisocyanate (a), (meth) acrylate (b) having one hydroxy group in the molecule, and (poly) oxyalkylene aryl phenyl ether (c). Is obtained. In this specification, (meth) acrylate refers to both acrylate and methacrylate.
Hereafter, the component which comprises the urethane (meth) acrylate of this invention is explained in full detail.

[(A) Organic polyisocyanate]
(A) The organic polyisocyanate is not particularly limited as long as it has a plurality of reactive isocyanate groups in the molecule. Specifically, the following compounds can be used. For example, an aromatic polyisocyanate having 6 to 20 carbon atoms (excluding carbon atoms in the isocyanate group, the same applies hereinafter) [for example, 1,3- or 1,4-phenylene diisocyanate, 2,4- or 2,6-tri Range isocyanate (TDI), 4,4'- or 2,4'-diphenylmethane diisocyanate (MDI), 1,5-naphthylene diisocyanate, 4,4 ', 4 "-triphenylmethane triisocyanate, m- or p- Isocyanatophenylsulfonyl isocyanate, etc.], polymethylene polyphenyl polyisocyanate (polymeric MDI), aliphatic polyisocyanate having 2 to 18 carbon atoms [for example, ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene dii Cyanate, 2,2,4-trimethylhexane diisocyanate, lysine diisocyanate (methyl 2,6-diisocyanatohexanoate), 2,6-diisocyanatomethylcaproate, bis (2-isocyanatoethyl) fumarate, bis ( 2-isocyanatoethyl) carbonate, etc.], alicyclic polyisocyanates having 8 to 15 carbon atoms [for example, isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated). TDI), bis (2-isocyanatoethyl) 4-cyclohexene-1,2-dicarboxylate and the like], araliphatic polyisocyanates having 8 to 15 carbon atoms [xylylene diisocyanate (XDI) , Tetramethylxylylene diisocyanate (TMXDI), etc.], and modified products of these polyisocyanates (modified products containing carbodiimide groups, uretdione groups, uretoimine groups, urea groups, burette groups, isocyanurate groups, etc.), and these Or a mixture of two or more thereof.
Among these, aliphatic or aromatic polyisocyanates (particularly diisocyanates) are preferable from the viewpoint of reactivity and safety, and HDI, IPDI and MDI are more preferable.

上記式（１）中、Ｒ_１は水素原子またはメチル基を表し、Ｒ_２Ｏは炭素原子数２〜４のオキシアルキレン基を表し、ｎは１〜５０の整数を表す。 [(B) (Meth) acrylate having one hydroxy group in the molecule]
(B) As (meth) acrylate which has one hydroxy group in a molecule | numerator, the compound represented, for example by following General formula (1) is mentioned.

In the above formula (1), R ₁ represents a hydrogen atom or a methyl group, R ₂ O represents an oxyalkylene group having 2 to 4 carbon atoms, and n represents an integer of 1 to 50.

Examples of the oxyalkylene group having 2 to 4 carbon atoms represented by R ₂ O include an oxyethylene group, an oxypropylene group, and an oxybutylene group.
n is preferably an integer of 3 to 25, more preferably an integer of 5 to 15.
When n is 2 or more, R ₂ O may be composed of two or more oxyalkylene groups. In that case, different types of oxyalkylene groups may be block addition or random addition.

Specific examples of the compound represented by the above formula (1) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth). Examples include acrylate, neopentyl glycol mono (meth) acrylate, polyethylene glycol mono (meth) acrylate, and various alkylene oxide adducts of these (meth) acrylate compounds.
Examples of the alkylene oxide include ethylene oxide, propylene oxide, and butylene oxide. When two or more kinds of alkylene oxide are added, block addition or random addition may be used. The added mole number of alkylene oxide is an integer of 1-50, preferably 3-25, more preferably 5-15.

式（２）中、Ｒ_３は単結合または炭素原子数１〜１０の炭化水素基を表し、ｐは１〜３の整数を表し、Ｒ_４Ｏは炭素原子数２〜４のオキシアルキレン基を表し、ｍは１〜５０の整数を表す。 [(C) (Poly) oxyalkylene aryl phenyl ether]
Examples of (c) (poly) oxyalkylene aryl phenyl ether include compounds represented by the following general formula (2).

In formula (2), R ₃ represents a single bond or a hydrocarbon group having 1 to 10 carbon atoms, p represents an integer of 1 to 3, and R ₄ O represents an oxyalkylene group having 2 to 4 carbon atoms. And m represents an integer of 1 to 50.

Examples of the hydrocarbon group having 1 to 10 carbon atoms in R ₃ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group. Can do. These hydrocarbon groups may be linear or branched.
Examples of the oxyalkylene group having 2 to 4 carbon atoms represented by R ₄ O include an oxyethylene group, an oxypropylene group, and an oxybutylene group.
m is preferably an integer of 3 to 25, more preferably an integer of 5 to 15.
When m is 2 or more, R ₄ O may be composed of two or more oxyalkylene groups. In that case, different types of oxyalkylene groups may be block addition or random addition.

  Specific examples of the compound represented by the above formula (2) include polyoxyethylene (mono, di or tri) phenyl phenyl ether, polyoxyethylene (mono, di or tri) benzyl phenyl ether, polyoxypropylene (mono, Di or tri) benzyl phenyl ether, polyoxyethylene (mono, di or tri) styrenated phenyl ether, polyoxypropylene (mono, di or tri) styrenated phenyl ether, polyoxyethylene polyoxypropylene (mono, di or tri) ) Styrenated phenyl ether and the like.

[Urethane (meth) acrylate (A)]
The urethane (meth) acrylate of the present invention is obtained by reacting the above-mentioned components (a) to (c), and the amount of these components used is the curability of the resulting urethane (meth) acrylate with respect to chemical energy rays. It is determined in consideration of etc.
Preferably, from the viewpoint of curability to active energy rays, sludge suppression, and the like, the component (b) and the component (c) are in a molar ratio with respect to the component (a), and the component (b): (c ) Component = 99: 1 to 50:50, preferably 98: 2 to 80:20, more preferably 97: 3 to 90:10.
The amount of component (b) and component (c) used relative to component (a) is such that the equivalent ratio of hydroxy group ((b) and component (c)) / isocyanate group (component (a)) is 1.00 to 1. It is preferable to use each so that it may become 0.05.

The method for producing the urethane (meth) acrylate of the present invention is not particularly limited, and each of the aforementioned components (a) to (c) may be charged all at once to carry out the urethanization reaction. (C) component may be reacted after reacting component and (b) component, or (a) component may be added to the mixture of (b) component and (c) component and reacted. .
The reaction temperature is 30 to 90 ° C, preferably 40 to 80 ° C, more preferably 50 to 70 ° C, and the reaction time is about 4 to 12 hours. Completion of the reaction can be easily confirmed by the disappearance of the NCO-derived peak by IR measurement.

  In the urethanization reaction, a known urethanization catalyst may be used for promoting the reaction. For example, as the catalyst, dibutyltin diacetate, dibutyltin dichloride, dibutyltin dilaurate, dibutylthiostannic acid, octyl acid first Organic metals such as tin, di-n-octyltin dilaurate, triethylenediamine, N-methylmorpholine, N, N-dimethyldidodecylamine, N-dodecylmorpholine, N, N-dimethylcyclohexylamine, N-ethylmorpholine, dimethyl Ethanolamine, N, N-dimethylbenzylamine, 1,8-diazabicyclo (5,4,0) undecene-7, isopropyl titanate, tetrabutyl titanate, oxyisopropyl vanadate, n-propyl zirconate, 1,4-diazabicyclo [2, 2 2] it can be used appropriately selecting the octane.

[Active energy ray-curable composition]
The active energy ray-curable composition containing the urethane (meth) acrylate (A) and the photopolymerization initiator (B) is also an object of the present invention.
Examples of the photopolymerization initiator (B) include benzoins such as benzoin, benzoin methyl ether, and benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1, 1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2,2-diethoxyacetophenone, N, N-dimethylamino Acetophenones such as acetophenone; anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquinone; -Thioxanthones such as dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone; Ketals such as acetophenone dimethyl ketal and benzyldimethyl ketal; Benzophenone, methylbenzophenone, 4,4'-dichloro Benzophenones such as benzophenone, 4,4′-bis (diethylamino) benzophenone, Michler's ketone, 4-benzoyl-4′-methyldiphenyl sulfide; 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (O-chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) 4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) -5-phenylimidazole dimer, 2 2,4,5-triarylimidazole dimers such as-(2,4-dimethoxyphenyl) -4,5-diphenylimidazole dimer; 9-phenylacridine, 1,7-bis (9,9'- Acridinyl) acridine derivatives such as heptane; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, oxime compounds and the like.

  The active energy ray-curable composition of the present invention is 20 to 99% by mass of the (A) urethane (meth) acrylate and 0.1% of the (B) photopolymerization initiator with respect to the total mass of the composition. It is preferable to contain in the ratio of -10 mass%.

Examples of the active energy rays to be irradiated include ultraviolet rays and electron beams. In the case of curing with ultraviolet rays, an ultraviolet irradiation device having a xenon lamp, a high-pressure mercury lamp, and a metal halide lamp as a light source is used, and the amount of light and the arrangement of the light sources are adjusted as necessary. For example, when using a high pressure mercury lamp for one lamp having a light intensity of a normal 80~250mW / cm ^2, preferably cured by the integrated quantity of light 50~5,000mJ / cm ^2.

  The active energy ray-curable composition of the present invention includes an antioxidant, a polymerization inhibitor, an anti-yellowing agent, an ultraviolet absorber, a filler, a dye / pigment, an oil, a plasticizer, a wax, a desiccant, a dispersant, Various additives such as wetting agents, emulsifying agents, gelling agents, stabilizers, antifoaming agents, leveling agents, thixotropic agents, flame retardants, fillers, reinforcing agents, matting agents, and crosslinking agents can be contained. .

  The active energy ray-curable composition of the present invention can be suitably used as a paint, a coating agent, a printing ink, an adhesive, a pressure-sensitive adhesive, a sealing material, various optical members (plastic lens, prism, optical fiber, etc.) and the like.

  EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Hereinafter, “parts” are based on mass unless otherwise specified.

(Production Example 1)
In a 500 mL five-necked flask equipped with a thermometer, stirring blade, and dropping funnel, 200 parts of polyethylene glycol (8EO) monoacrylate, 26.9 parts of polyoxyethylene polyoxypropylene (15EO5PO) tristyrenated phenyl ether, dibutyltin dilaurate 0 .03 copies were charged. Next, 39.1 parts of hexamethylene-1,6-diisocyanate (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) H) was added dropwise over 30 minutes with stirring. It was made to react at 70 degreeC until the peak derived from NCO disappeared by IR measurement, and urethane acrylate (A-1) was obtained.

(Production Example 2)
The same procedure as in Production Example 1 was carried out except that 26.9 parts of polyoxyethylene polyoxypropylene (15EO5PO) tristyrenated phenyl ether was changed to 14.6 parts of polyoxypropylene (5PO) tristyrenated phenyl ether. (A-2) was obtained.

(Production Example 3)
Hexamethylene-1,6-diisocyanate (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) H) 39.1 parts is isophorone diisocyanate (Evonik Co., Ltd., VESTANAT (registered trademark) IPDI) 51 Except having changed to 6 parts, it carried out similarly to manufacture example 1 and obtained urethane acrylate (A-3).

(Production Example 4)
A flask similar to Production Example 1 was charged with 200 parts of polypropylene glycol (10PO) monoacrylate, 14.6 parts of polyoxyethylene (12EO) distyrenated phenyl ether, and 0.03 part of dibutyltin dilaurate. Next, 29.6 parts of hexamethylene-1,6-diisocyanate (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) H) was added dropwise over 30 minutes with stirring. It was made to react at 70 degreeC until the peak derived from NCO disappeared by IR measurement, and urethane acrylate (A-4) was obtained.

(Comparative Production Example 1)
In the same flask as in Production Example 1, 230 parts of polyethylene glycol (8EO) monoacrylate and 0.03 part of dibutyltin dilaurate were charged. Next, after adding 42.9 parts of hexamethylene-1,6-diisocyanate (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) H) dropwise over 30 minutes while stirring at room temperature. The urethane acrylate (A-5) was obtained by reacting at 70 ° C. until the peak derived from NCO disappeared by IR measurement.

(Comparative Production Example 2)
Hexamethylene-1,6-diisocyanate (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) H) 42.9 parts is isophorone diisocyanate (Evonik Co., Ltd., VESTANAT (registered trademark) IPDI) 56 Except having changed to 0.7 parts, it carried out similarly to the comparative manufacture example 1, and obtained urethane acrylate (A-6).

(Comparative Production Example 3)
In the same flask as in Production Example 1, 230 parts of polypropylene glycol (10PO) monoacrylate and 0.03 part of dibutyltin dilaurate were charged. Next, 32.5 parts of hexamethylene-1,6-diisocyanate (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) H) was added dropwise over 30 minutes with stirring. It was made to react at 70 degreeC until the peak derived from NCO disappeared by IR measurement, and urethane acrylate (A-7) was obtained.

(Comparative Production Example 4)
Performed in the same manner as in Production Example 1 except that 26.9 parts of polyoxyethylene polyoxypropylene (15EO5PO) tristyrenated phenyl ether was changed to 14.9 parts of polyoxyethylene polyoxypropylene (2EO6PO) 2-hexyldecyl ether. Then, urethane acrylate (A-8) was obtained.

(Comparative Production Example 5)
Except that 14.6 parts of polyoxyethylene (12EO) distyrenated phenyl ether was changed to 7.9 parts of polyoxyethylene (10EO) methyl ether, the same procedure as in Production Example 4 was carried out to obtain urethane acrylate (A-9). It was.

(Comparative Production Example 6)
Except that 14.6 parts of polyoxyethylene (12EO) distyrenated phenyl ether was changed to 10.2 parts of polyoxypropylene (10PO) methyl ether, the same procedure as in Production Example 4 was carried out to obtain urethane acrylate (A-10). It was.

(Comparative Production Example 7)
The same procedure as in Production Example 4 was conducted except that 14.6 parts of polyoxyethylene (12EO) distyrenated phenyl ether was changed to 10.2 parts of polyoxyethylene polyoxypropylene (4EO4PO) 2-butyloctyl ether, and urethane acrylate ( A-11) was obtained.

(Performance evaluation)
40 parts of urethane acrylates A1 to A11 obtained in Production Examples 1 to 4 or Comparative Production Examples 1 to 7, 3 parts of Irgacure 184 (manufactured by Ciba Specialty, 1-hydroxycyclohexyl phenyl ketone) as a photopolymerization initiator, and isopropanol 5 as a solvent 60 parts of water were mixed as part and solid content adjustment, and active energy ray-curable composition solutions of Examples 1 to 4 and Comparative Examples 1 to 7 were prepared.
Also, 36 parts of urethane acrylate A-5 obtained in Comparative Production Example 1, 3 parts of Irgacure, 5 parts of isopropanol, 4 parts of surfactant S-1 (polyoxyethylene polyoxypropylene (15EO5PO) tristyrenated phenyl ether), The active energy ray-curable composition solution of Comparative Example 8 containing 60 parts of water and urethane acrylate A-5 in 38 parts of urethane acrylate A-7 obtained in Comparative Production Example 3 were used, and surfactant S-1 was used as the interface. Activator S-2 (polyoxyethylene (12EO) distyrenated phenyl ether) An active energy ray-curable composition solution of Comparative Example 9 prepared in the same manner as Comparative Example 8 was prepared except that the amount was changed to 2 parts.
The evaluation shown below was implemented using these samples. Table 1 shows formulation examples and evaluation results.

(1) Curability with respect to active energy rays Each of the above-mentioned active energy ray-curable composition solutions was coated on a glass substrate with a 50 µm bar coater and dried with a hot air dryer at 100 ° C for 5 minutes. After leaving at room temperature for 10 minutes, it was irradiated with a 100 mW / cm ² UV irradiator to form a cured film. The tackiness of the cured film was evaluated, and the number of irradiations until tackiness disappeared was counted. Table 1 shows the results of counting the number of times of irradiation.

(2) Pencil hardness Each of the above-mentioned active energy ray-curable composition solutions was coated on a glass substrate with a 50 μm bar coater and dried with a hot air dryer at 100 ° C. for 5 minutes. After standing at room temperature for 10 minutes, the integrated light quantity is set to 400 mJ / cm ² with a 100 mW / cm ² UV irradiator.
V cured to form a cured film. The obtained cured film was evaluated according to JIS K 5600 5-4, and the pencil hardness was determined. The cured film is required to have at least a pencil hardness of H or higher.

(3) Sludge inhibiting ability The amount of sludge generated after each active energy ray-curable composition solution was allowed to stand still for 1 week was visually observed and evaluated according to the following evaluation criteria.
○: No sludge is seen △: Slight sludge is seen ×: A large amount of sludge is seen

(4) Foam suppression 50 mL of each of the above-mentioned active energy ray-curable composition solutions was taken in a 100 mL graduated cylinder and bubbled with dry air (30 mL / min) for 30 minutes. At this time, the presence or absence of generation of bubbles in the approximate solution and the height of the bubbles when bubbles were generated were observed and evaluated according to the following evaluation criteria.
○: No foaming is observed. △: Foaming does not overflow from the container. ×: Foaming so as to overflow from the container.

As shown in Table 1, the active energy ray-curable compositions (Examples 1 to 4) using the urethane (meth) acrylates A-1 to A-4 of the present invention have a curability and a pencil hardness, and High evaluation was obtained in almost all evaluations of sludge suppression ability and foam suppression.
On the other hand, urethane (meth) acrylates other than the present invention, that is, urethane (meth) acrylates A-5 to A-7 prepared without using (c) (poly) oxyalkylene aryl phenyl ether, and the above (c) In place of components, active energy ray-curable compositions (Comparative Examples 1 to 7) using urethane (meth) acrylates A-8 to A-11 prepared using (poly) oxyalkylene alkyl ether In that case, some of the evaluations were highly evaluated, but a result satisfying all the four evaluations could not be obtained. Above all, with regard to the evaluation of curability, most of the results were the same as or less than the results of Examples, and it was found that it was difficult to achieve both sludge suppression ability and foam suppression. Further, active energy ray curing using urethane (meth) acrylate A-5 or A-7 prepared without using (poly) oxyalkylene aryl phenyl ether and separately adding polyoxyalkylene aryl phenyl ether as a surfactant Example 1 using urethane (meth) acrylate (A-1, A-4) prepared by using polyoxyalkylene aryl phenyl ether as one component even in the composition (Comparative Example 8 and Comparative Example 9) And compared with Example 4, the result of being inferior in the point of hardness and foam suppression property was obtained.
As described above, the urethane (meth) acrylate of the present invention employs (poly) oxyalkylene arylphenyl ether as a component constituting the urethane (meth) acrylate, that is, has one hydroxy group in the molecule relative to the organic polyisocyanate. By combining (meth) acrylate and (poly) oxyalkylene aryl phenyl ether, the resulting urethane (meth) acrylate has improved curability against active energy rays and suppressed sludge and foaming. It was confirmed that it was possible.

Claims (3)

Urethane (meth) acrylate obtained by reacting organic polyisocyanate (a) with (meth) acrylate (b) having one hydroxy group in the molecule and (poly) oxyalkylene arylphenyl ether (c). The component (b) and the component (c) are reacted with the organic polyisocyanate (a) in a molar ratio of (b) :( c) = 99: 1 to 50:50. Urethane (meth) acrylate described in 1. An active energy ray-curable composition containing the urethane (meth) acrylate (A) according to claim 1 or 2 and a photopolymerization initiator (B).