JP2018178093A - Active energy ray curable resin composition and coating agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an active energy ray-curable resin composition containing a urethane (meth) acrylate-based composition which is hard to curl because of small curing shrinkage and can form a cured coating film having excellent hardness and flexibility. To provide a product and a coating agent using the product. A urethane obtained by reacting a hydroxyl group of (meth) acrylate in a (meth) acrylate mixture (A), which is a reaction product of pentaerythritol and (meth) acrylic acid, with an isocyanate group of polyhydric isocyanate (CA). The hydroxyl group of the (meth) acrylate in the (meth) acrylate-based composition [I] and the (meth) acrylate mixture (B), which is a reaction product of dipentaerythritol and the (meth) acrylic acid, and the polyhydric isocyanate ( It contains a urethane (meth) acrylate-based composition [II] in which the isocyanate group of CB) has reacted, and the hydroxyl value of the mixture (A) is 200 mgKOH / g or more, and the hydroxyl group of the mixture (B). An active energy ray-curable resin composition having a value of 40 mgKOH / g or more. [Selection diagram] None

Description

  The present invention relates to an active energy ray-curable resin composition and a coating agent comprising a urethane (meth) acrylate composition, and more specifically, a curl due to a small cure shrinkage when a cured coating film is formed. The present invention relates to an active energy ray-curable resin composition which can form a coating film which is hard to be formed and which is further excellent in hardness and flexibility, and a coating agent using the same.

  Conventionally, as curing of active energy ray curable resin compositions is completed by irradiation of active energy rays such as radiation or ultraviolet rays for a very short time, as coating agents, adhesives, anchor coating agents, etc. for various substrates It is widely used, and urethane (meth) acrylate compounds and polyfunctional monomers are used as the curing component therein. However, when the active energy ray-curable resin composition is used as a coating agent, particularly as a coating agent for a hard coat, there is a problem that curing shrinkage of the coating occurs and the cured coating tends to curl. There is a need for difficult things.

  In addition, since a coating agent for hard coat is also used as a protective film in a bent portion of a molded product or a display, it is required to have flexibility such that cracks do not easily occur even if a plastic film on which a cured coating is formed is bent. There is.

  With regard to the above-mentioned curl resistance, a curable resin composition (for example, see Patent Document 1) in which inorganic fine particles are added to a curable resin in order to suppress curing shrinkage (urethane having a high molecular weight as a curing component) A curable resin composition containing (meth) acrylate (see, for example, Patent Document 2), and further, a hydroxyl group in a (meth) acrylic acid adduct of pentaerythritol having a hydroxyl value of 130 mg KOH / g or more. A curable resin composition (see, for example, Patent Document 3) comprising a urethane (meth) acrylate formed by reacting an isocyanate group of a polyvalent isocyanate compound is proposed.

  In addition, as a method for increasing the hardness of the hard coat layer in order to improve scratch resistance, for example, a resin composition comprising dipentaerythritol hexaacrylate and tripentaerythritol octaacrylate is made of triacetyl cellulose having a thickness of 80 μm. There is known a technology in which a film obtained by applying and curing a film with a film thickness of 12 μm expresses a hardness of about 5 H of pencil hardness (see, for example, Patent Document 4).

Unexamined-Japanese-Patent No. 2010-77292 Unexamined-Japanese-Patent No. 2010-180319 JP, 2012-229412, A JP, 2009-286924, A

  However, in the disclosed technology of Patent Document 1, there is a problem that the organic solvents which can be used are limited in consideration of the compatibility between the inorganic fine particles and the curable resin, or the possibility of occurrence of surface abnormality of the coating film becomes high. Furthermore, since inorganic fine particles are generally expensive, resins and paints containing the inorganic particles are also expensive, and the practical use of the curable resin is limited to special applications.

  Further, in the disclosed technique of Patent Document 2 described above, since the production method for increasing the molecular weight of urethane (meth) acrylate used as a curing component is a multistage reaction, the operation becomes complicated, and the scratch resistance of the coating film Would have fallen.

  On the other hand, in the art disclosed in Patent Document 3, a cured coating film having a small curing shrinkage and a suppressed curling can be obtained, but the hardness is insufficient.

  Furthermore, in the disclosed technique of Patent Document 4, although the surface hardness of the cured coating film is high, the curling generated during curing is large, and since it is hard and brittle, a crack occurs when the coating film is bent. Met.

  Therefore, in the present invention, when a cured coating film is formed under such a background, urethane (meta) which can form a coating film excellent in curling resistance and also excellent in flexibility because the curing shrinkage is small. ) It is an object of the present invention to provide an active energy ray-curable resin composition containing an acrylate composition and a coating agent using the same.

  However, as a result of extensive researches in view of such circumstances, the present inventors are reaction products of pentaerythritol and (meth) acrylic acid as a curing component, and have a hydroxyl value higher than that of the usual ones described below (meta ) A urethane (meth) acrylate composition obtained by reacting a (meth) acrylate having a hydroxyl group in a mixture (A) of acrylates (a1) to (a4) with a polyvalent isocyanate (CA); The (meth) acrylate having a hydroxyl group in a mixture (B) of the following (meth) acrylates (b1) to (b6), which is a reaction product of erythritol and (meth) acrylic acid, is reacted with a polyvalent isocyanate (CB) Curing shrinkage is small by using both urethane (meth) acrylate compositions of the urethane (meth) acrylate composition obtained by Ku hardly curled, and found that the hardness and cured coating film excellent in flexibility can be obtained, and have completed the present invention.

That is, the gist of the present invention relates to (meth) acrylates (a1) to (a1) in a mixture (A) of the following (meth) acrylates (a1) to (a4) which is a reaction product of pentaerythritol and (meth) acrylic acid. Urethane (meth) acrylate composition [I] in which a3) and polyvalent isocyanate (CA) are reacted, and the following (meth) acrylate (b1) which is a reaction product of dipentaerythritol and (meth) acrylic acid (H) containing a urethane (meth) acrylate composition [II] in which (meth) acrylates (b1) to (b5) in the mixture (B) of (b6) to (b) react with the polyvalent isocyanate (CB) And the hydroxyl value of the mixture (A) is 200 mg KOH / g or more, and the hydroxyl value of the mixture (B) is 40 mg KOH / g or more. It relates resistant resin composition.
Mixture (A)
(A1) pentaerythritol mono (meth) acrylate (a2) pentaerythritol di (meth) acrylate (a3) pentaerythritol tri (meth) acrylate (a4) pentaerythritol tetra (meth) acrylate mixture (B)
(B1) dipentaerythritol mono (meth) acrylate (b2) dipentaerythritol di (meth) acrylate (b3) dipentaerythritol tri (meth) acrylate (b4) dipentaerythritol tetra (meth) acrylate (b5) dipentaerythritol Penta (meth) acrylate (b6) dipentaerythritol hexa (meth) acrylate

  Moreover, in this invention, the coating agent formed by containing the said active energy ray curable resin composition is also provided.

  The active energy ray-curable resin composition of the present invention is less likely to curl due to a small cure shrinkage, and can form a cured coating film excellent in hardness and flexibility, and in particular, a coating for a hard coat It is useful for various uses, such as an agent.

  When the content ratio of pentaerythritol di (meth) acrylate (a2) in the mixture (A) of the above (meth) acrylates (a1) to (a4) is 10 to 50% by weight, the point of coexistence of hardness and flexibility To become superior.

  When the content ratio of pentaerythritol di (meth) acrylate (a2) to the total of (meth) acrylates (a1) to (a3) is 15 to 55% by weight, it becomes superior by the point of coexistence of hardness and flexibility. .

  When the weight average molecular weight of the urethane (meth) acrylate composition [I] is 1,000 to 20,000, the handling ease of the active energy ray curable resin composition will be excellent.

  When the content of dipentaerythritol penta (meth) acrylate (b5) in the mixture (B) of the (meth) acrylates (b1) to (b6) is 15 to 60% by weight, the hardness and the flexibility are further enhanced. It will be excellent in coexistence.

  When the content ratio of dipentaerythritol penta (meth) acrylate (b5) with respect to the total of (meth) acrylates (b1) to (b5) is 45 to 90% by weight, it becomes more excellent in both hardness and flexibility. .

  When the content ratio of dipentaerythritol tetra (meth) acrylate (b4) in the mixture (B) of the (meth) acrylates (b1) to (b6) is 1 to 35% by weight, excellent flexibility can be obtained. .

  When the content ratio of dipentaerythritol tetra (meth) acrylate (b4) with respect to the total of the (meth) acrylates (b1) to (b5) is 2 to 40% by weight, it becomes more excellent in flexibility.

  When the weight average molecular weight of the urethane (meth) acrylate composition [II] is 1,000 to 20,000, the handling ease of the active energy ray curable resin composition will be excellent.

The present invention will be described in detail below.
In the present invention, (meth) acrylic means acrylic or methacrylic, (meth) acryloyl means acryloyl or methacryloyl, and (meth) acrylate means acrylate or methacrylate.

The active energy ray-curable resin composition of the present invention is a (meth) acrylate in a mixture (A) of the following (meth) acrylates (a1) to (a4) obtained by reacting pentaerythritol with (meth) acrylic acid Urethane (meth) acrylate composition [I] formed by reacting (a1) to (a3) with polyvalent isocyanate (CA), and the following ((1) obtained by reacting dipentaerythritol with (meth) acrylic acid Urethane (meth) acrylate composition [II] obtained by reacting (meth) acrylates (b1) to (b5) and polyvalent isocyanate (CB) in a mixture (B) of meta) acrylates (b1) to (b6) ] Is contained.
Mixture (A)
(A1) pentaerythritol mono (meth) acrylate (a2) pentaerythritol di (meth) acrylate (a3) pentaerythritol tri (meth) acrylate (a4) pentaerythritol tetra (meth) acrylate mixture (B)
(B1) dipentaerythritol mono (meth) acrylate (b2) dipentaerythritol di (meth) acrylate (b3) dipentaerythritol tri (meth) acrylate (b4) dipentaerythritol tetra (meth) acrylate (b5) dipentaerythritol Penta (meth) acrylate (b6) dipentaerythritol hexa (meth) acrylate

<Urethane (Meth) Acrylate Composition [I]>
First, the urethane (meth) acrylate composition [I] will be described.
In the present invention, the hydroxyl value of the mixture (A) of the above (meth) acrylates (a1) to (a4) obtained by reacting the above pentaerythritol and (meth) acrylic acid is 200 mg KOH / g or more. It is preferably 210 to 380 mg KOH / g, particularly preferably 230 to 320 mg KOH / g.

  When the hydroxyl value of the mixture (A) is too small, the weight average molecular weight of the urethane (meth) acrylate composition [I] decreases, and the curing shrinkage at the time of curing becomes large, so the curling tends to occur easily. Furthermore, the flexibility tends to be reduced. In general, when the above-mentioned hydroxyl value is too large, the viscosity is improved with the increase of molecular weight, and it tends to be difficult to handle.

  The hydroxyl value in the present invention can be determined by the method according to JIS K 0070 1992.

  In the present invention, the hardness that the content of pentaerythritol di (meth) acrylate (a2) in the mixture (A) of the (meth) acrylates (a1) to (a4) is 10 to 50% by weight It is preferable from the viewpoint of achieving both flexibility and flexibility, particularly preferably 15 to 45% by weight, and further preferably 20 to 40% by weight. When the content ratio is too small, the flexibility tends to decrease, and when the content ratio is too large, the hardness tends to decrease or the viscosity increases.

  Furthermore, the content ratio of pentaerythritol di (meth) acrylate (a2) to the total of (meth) acrylates (a1) to (a3) is preferably 15 to 55% by weight from the viewpoint of achieving both hardness and flexibility, Particularly preferably, it is 20 to 50% by weight, more preferably 25 to 45% by weight. When the content ratio is too small, the flexibility tends to decrease, and when the content ratio is too large, the hardness tends to decrease or the viscosity increases.

  In the present invention, pentaerythritol and (meth) acrylic acid are reacted to prepare a (meth) acrylic acid adduct of pentaerythritol. The reaction of pentaerythritol and (meth) acrylic acid is carried out by a known general method. be able to. In this reaction, pentaerythritol mono (meth) acrylate (a1) in which one (meth) acrylic acid is added to pentaerythritol, pentaerythritol di (meth) acrylate (a2) in which two adducts are added, and penta in which three adducts are added A mixture (A) containing erythritol tri (meth) acrylate (a3) and pentaerythritol tetra (meth) acrylate (a4) with four additions is obtained to obtain a mixture (A) having the above hydroxyl value as a whole be able to.

  The mixture (A) may contain side reaction products such as a Michael adduct of acrylic acid.

  The adjustment of the hydroxyl value can be performed, for example, by adjusting the content ratio of (meth) acrylates (a1) to (a4).

  In the present invention, the above-mentioned polyvalent isocyanate (CA) reacts with the above (meth) acrylates (a1) to (a3). Specifically, for example, tolylene diisocyanate, diphenylmethane diisocyanate, polyphenylmethane polyisocyanate Aromatic polyisocyanates such as modified diphenylmethane diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, phenylene diisocyanate and naphthalene diisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate and lysine triisocyanate Hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate Aliphatic polyisocyanates such as anate and norbornene diisocyanate; or trimer compounds or multimer compounds of these polyisocyanates, allophanate type polyisocyanates, burette type polyisocyanates, water dispersion type polyisocyanates (for example, manufactured by Tosoh Corporation) “Aquanate 105”, “Aquanate 120”, “Aquanate 210”, etc., and the like. These can be used alone or in combination of two or more.

  In addition, the polyisocyanate (CA) may be a reaction product of the polyisocyanate and various polyols. As such polyols, for example, low molecular weight polyols and high molecular weight polyols, particularly polyolefins obtained by reacting polyether-based polyols, polyester-based polyols, polycarbonate-based polyols, polybutadiene-based polyols, ethylene-isoprene-butadiene, etc. A system polyol or its hydrogenated product, a polyolefin type polyol other than the above, a (meth) acrylic type polyol, etc. are mentioned.

  Among them, alicyclic polyisocyanates and aromatic polyisocyanates are preferable in view of strength, and isophorone diisocyanate, hydrogenated xylylene diisocyanate, xylylene diisocyanate and tolylene diisocyanate are particularly preferable.

  In the present invention, the urethane (meth) acrylate composition [I] is selected from the hydroxyl groups of (meth) acrylates (a1) to (a3) in the mixture (A) of the above (meth) acrylates (a1) to (a4) And the isocyanate group of the said polyvalent isocyanate (CA) can be made to react. In this case, in the urethane (meth) acrylate composition [I], one in which (meth) acrylate (a1) and polyvalent isocyanate (CA) are reacted, (meth) acrylate (a2) and polyvalent isocyanate (CA) In the reaction system, the product of reaction of (meth) acrylate (a3) and the reaction of polyvalent isocyanate (CA) is contained, and further, in the system, not (meth) acrylate (a1) to (a3) It also contains (meth) acrylate (a4) which does not take part in the reaction product or reaction.

  In the reaction of (meth) acrylates (a1) to (a3) and polyvalent isocyanate (CA), the functional group molar ratio of hydroxyl group and isocyanate group is adjusted, and if necessary, it is carried out using a reaction catalyst described later Can.

  The reaction molar ratio of charging of the polyvalent isocyanate (CA) and the mixture (A) of (meth) acrylates (a1) to (a4) is as follows when the number of isocyanate groups of the polyvalent isocyanate (CA) is two: Polyisocyanate (CA): (meth) acrylate mixture (A) is preferably 1: 1 to 1: 5, particularly preferably 1: 1 to 1: 3, more preferably 1: 1 to 1: 2 It is.

  When the proportion of the mixture (A) is too large, low molecular weight monomers increase and curing shrinkage becomes large, so curling tends to be large, and when the proportion of the mixture (A) is too small, unreacted polyvalent isocyanate (CA) tends to remain, and the stability and safety of the cured coating film tend to be reduced.

  The reaction of (meth) acrylates (a1) to (a3) and polyvalent isocyanate (CA) in the (meth) acrylate mixture (A) is generally carried out by reacting the above mixture (A) and polyvalent isocyanate (CA) in a reactor The reaction may be carried out collectively or separately.

  In the above reaction, it is also preferable to use a catalyst for the purpose of promoting the reaction, and examples of such a catalyst include dibutyltin dilaurate, dibutyltin diacetate, trimethyltin hydroxide, tetra-n-butyltin and bisacetylacetonate. Organometallic compounds such as zinc, zirconium tris (acetylacetonate) ethylacetoacetate, zirconium tetraacetylacetonate, etc .; tin octylate, tin octenate, zinc hexanoate, zinc octenate, zinc stearate, zirconium 2-ethylhexanoate Metal salts such as cobalt naphthenate, stannous chloride, stannic chloride, potassium acetate, etc .; triethylamine, triethylenediamine, benzyldiethylamine, 1,4-diazabicyclo [2,2,2] octane, 1,8-diazabicyclo [ 5,4 0] Amine-based catalysts such as undecene, N, N, N ', N'-tetramethyl-1,3-butanediamine, N-methylmorpholine, N-ethylmorpholine; bismuth nitrate, bismuth bromide, bismuth iodide, In addition to bismuth sulfide and the like, organic bismuth compounds such as dibutyl bismuth dilaurate and dioctyl bismuth dilaurate, bismuth 2-ethylhexanoate, bismuth naphthenate, bismuth isodecanoate, bismuth neodecanoate, bismuth laurate and maleate Bismuth-based catalysts such as bismuth salts of organic acids such as bismuth salts, bismuth stearate, bismuth oleate, bismuth linoleate, bismuth acetate, bismuth bis bis neodecanoate, bismuth disalicylate, bismuth di gallate, and the like. Etc., among which dibutyltin di Ureto, 1,8-diazabicyclo [5,4,0] undecene is preferred. These can be used singly or in combination of two or more.

  Further, in the above reaction, it is preferable to further use a polymerization inhibitor. As the above-mentioned polymerization inhibitor, publicly known general agents used as a polymerization inhibitor can be used. For example, p-benzoquinone, naphthoquinone, toluquinone, 2,5-diphenyl-p-benzoquinone, hydroquinone, 2, Quinones such as 5-di-t-butylhydroquinone, methylhydroquinone, mono-t-butylhydroquinone, etc., aromatics such as 4-methoxyphenol, 2,6-di-t-butylcresol, p-t-butylcatechol Etc. can be mentioned. Among them, aromatics are preferable, and 4-methoxyphenol and 2,6-di-t-butylcresol are particularly preferable. These can be used alone or in combination of two or more.

  In the reaction, organic solvents having no functional group reactive to isocyanate groups, for example, esters such as ethyl acetate and butyl acetate, ketones such as methyl ethyl ketone and methyl isobutyl ketone, aromatics such as toluene and xylene Organic solvents such as the like can be used. These can be used alone or in combination of two or more.

  The reaction temperature is generally 30 to 90 ° C., preferably 40 to 80 ° C., and the reaction time is generally 4 to 72 hours, preferably 8 to 48 hours.

  Thus, the urethane (meth) acrylate composition [I] used in the present invention is obtained.

  The weight average molecular weight of the urethane (meth) acrylate composition [I] is preferably 1,000 to 20,000, particularly preferably 2,000 to 18,000, and still more preferably 3,000 to 16 , 000. When the weight-average molecular weight is too small, the cured coating tends to be brittle, and when it is too large, the viscosity becomes high and it becomes difficult to handle.

  In addition, the said weight average molecular weight is a weight average molecular weight by standard polystyrene molecular weight conversion, and one column: ACQUITY APC XT 450, ACQUITY APC XT 200 in a high performance liquid chromatograph (manufactured by Waters, "ACQUITY APC system"). And a total of four ACQUITY APC XT 45 in series.

  The content of urethane (meth) acrylate in the above urethane (meth) acrylate composition [I] is preferably 50% by weight or more, particularly preferably 60% by weight or more, still more preferably 70% by weight or more, particularly preferably It is 80% by weight or more. The upper limit is usually 95% by weight.

<Urethane (Meth) Acrylate Composition [II]>
Next, the urethane (meth) acrylate composition [II] will be described.
In the present invention, the hydroxyl value of the mixture (B) of the above (meth) acrylates (b1) to (b6) obtained by reacting the above dipentaerythritol and (meth) acrylic acid is 40 mg KOH / g or more. Is preferably 43 to 130 mg KOH / g, particularly preferably 45 to 125 mg KOH / g, and more preferably 70 to 120 mg KOH / g.

  If the hydroxyl value of the mixture (B) is too small, the content of dipentaerythritol hexa (meth) acrylate which is low in molecular weight and has a large number of ethylenically unsaturated groups and does not react with isocyanate increases, so cure shrinkage during curing Because it becomes large, it tends to curl, and furthermore, the flexibility tends to decrease. In general, when the above-mentioned hydroxyl value is too large, the viscosity is improved with the increase of molecular weight, and it tends to be difficult to handle.

  In the present invention, the hardness and the fact that the content of dipentaerythritol penta (meth) acrylate (b5) in the mixture (B) of the above (meth) acrylates (b1) to (b6) is 15 to 60% by weight It is preferable from the viewpoint of compatibility with flexibility, particularly preferably 20 to 55% by weight, and further preferably 25 to 55% by weight. When the content ratio is too small, the flexibility tends to decrease, and when the content ratio is too large, the hardness tends to decrease or the viscosity increases.

  The content ratio of dipentaerythritol penta (meth) acrylate (b5) to the total of (meth) acrylates (b1) to (b5) is preferably 45 to 90% by weight from the viewpoint of achieving both hardness and flexibility, in particular It is preferably 50 to 90% by weight, more preferably 55 to 90% by weight. When the content ratio is too small, the flexibility tends to decrease, and when the content ratio is too large, the hardness tends to decrease or the viscosity increases.

  The content of dipentaerythritol tetra (meth) acrylate (b4) in the mixture (B) of the (meth) acrylates (b1) to (b6) is preferably 1 to 35% by weight from the viewpoint of flexibility. Particularly preferably, it is 2 to 30% by weight, more preferably 3 to 25% by weight. When the content ratio is too small, the flexibility tends to decrease, and when the content ratio is too large, the hardness tends to decrease or the viscosity increases.

  The content of dipentaerythritol tetra (meth) acrylate (b4) relative to the total of (meth) acrylates (b1) to (b5) is preferably 2 to 40% by weight from the viewpoint of flexibility, particularly preferably 3 to 3 It is 35% by weight, more preferably 4 to 30% by weight. When the content ratio is too small, the flexibility tends to decrease, and when the content ratio is too large, the hardness tends to decrease or the viscosity increases.

  In the present invention, dipentaerythritol and (meth) acrylic acid are reacted to prepare a (meth) acrylic acid adduct of dipentaerythritol. The reaction of dipentaerythritol with (meth) acrylic acid is known in general. Can be done in the In such a reaction, dipentaerythritol mono (meth) acrylate (b1) in which one (meth) acrylic acid is added to dipentaerythritol, dipentaerythritol di (meth) acrylate (b2) in which two are added, three Added dipentaerythritol tri (meth) acrylate (b3), four added dipentaerythritol tetra (meth) acrylate (b4), five added dipentaerythritol penta (meth) acrylate (b5), six added A mixture (B) containing dipentaerythritol hexa (meth) acrylate (b6) is obtained, and a mixture (B) satisfying the above-mentioned hydroxyl value can be obtained as a whole.

  The mixture (B) may contain side reaction products such as a Michael adduct of acrylic acid.

  The adjustment of the hydroxyl value can be performed, for example, by adjusting the content ratio of (meth) acrylates (b1) to (b6).

  In the present invention, the above-mentioned polyvalent isocyanate (CB) reacts with the above (meth) acrylates (b1) to (b5), and specifically, the same as the polyvalent isocyanate (CA) described above Can be illustrated. The polyvalent isocyanate (CB) may be the same as or different from the polyvalent isocyanate (CA).

  In addition, as the polyisocyanate (CB), a reaction product of the above-mentioned polyisocyanate and a polyol may be used. As such a polyol, for example, a low molecular weight polyol or a high molecular weight polyol, specifically, a polyether based polyol, a polyester based polyol, a polycarbonate based polyol, a polybutadiene based polyol, an ethylene isoprene butadiene, etc. are reacted. Polyolefin-based polyols or hydrogenated products thereof, polyolefin-based polyols other than the above, (meth) acrylic-based polyols and the like.

  Among these polyvalent isocyanates (CB), cycloaliphatic polyisocyanates and aromatic polyisocyanates are preferable in view of weatherability and strength, and particularly preferably isophorone diisocyanate, hydrogenated xylylene diisocyanate, xylylene diisocyanate. Di-isocyanate, tolylene diisocyanate.

  In the present invention, the urethane (meth) acrylate composition [II] is selected from the hydroxyl groups of (meth) acrylates (b1) to (b5) in the mixture (B) of the above (meth) acrylates (b1) to (b6) It can be obtained by reacting the above-mentioned polyisocyanate (CB) with an isocyanate group. In this case, in the urethane (meth) acrylate composition [II], one in which (meth) acrylate (b1) is reacted with polyvalent isocyanate (CB), (meth) acrylate (b2) and polyvalent isocyanate (CB) In which (meth) acrylate (b3) and polyvalent isocyanate (CB) are reacted, in which (meth) acrylate (b4) and polyvalent isocyanate (CB) are reacted, (meth) acrylate (b5) The product of the reaction of the polyvalent isocyanate (CB) and the polyvalent isocyanate (CB) will be contained, and furthermore, in the system, the (meth) acrylate (b1) to (b5) unreacted matter and (meth) acrylate not involved in the reaction b6) etc. will also be contained.

  The reaction molar ratio of the charge of the polyvalent isocyanate (CB) and the mixture (B) of (meth) acrylates (b1) to (b6) is, for example, the case where the number of isocyanate groups of polyvalent isocyanate (CB) is 2 The polyvalent isocyanate (CB) :( meth) acrylate mixture (B) is preferably 1: 1 to 1: 5, particularly preferably 1: 1 to 1: 4, more preferably 1: 1 to 1. : 3.

  If the proportion of the mixture (B) is too large, low molecular weight monomers increase and curing shrinkage becomes large, so curling tends to be large, and if the proportion of the mixture (B) is too small, unreacted polyvalent isocyanate (CB) tends to remain, and the stability and safety of the cured coating film tend to be reduced.

  The reaction of (meth) acrylates (b1) to (b5) and the polyvalent isocyanate (CB) in the (meth) acrylate mixture (B) is generally carried out by reacting the above mixture (B) and the polyvalent isocyanate (CB) in a reactor The reaction may be carried out collectively or separately.

  In the above reaction, it is also preferable to use a catalyst for the purpose of promoting the reaction, and as such a catalyst, the same one as described in the above urethane (meth) acrylate composition [I] can be exemplified.

  Further, in the above reaction, also in the case of using a polymerization inhibitor and an organic solvent having no functional group reactive to an isocyanate group, it is the same as that described in the above urethane (meth) acrylate composition [I]. Can be illustrated.

  Moreover, in preparation of urethane (meth) acrylate type composition [II], it can carry out according to preparation of said urethane (meth) acrylate type composition [I].

  Thus, the urethane (meth) acrylate composition [II] used in the present invention is obtained.

The weight average molecular weight of the urethane (meth) acrylate composition [II] is preferably 1,000 to 20,000, more preferably 1,500 to 18,000, and particularly preferably 2,000 to 16 , 000. When the weight-average molecular weight is too small, the cured coating tends to be brittle, and when it is too large, the viscosity becomes high and it becomes difficult to handle.
In addition, the measuring method of said weight average molecular weight is the same as the said measuring method.

The viscosity of the urethane (meth) acrylate composition [II] at 60 ° C. is preferably 1,000 to 300,000 mPa · s, particularly preferably 1,500 to 200,000, and still more preferably It is 2,000 to 100,000 mPa · s. If the viscosity is outside the above range, the coatability tends to decrease.
In addition, the measuring method of the viscosity in 60 degreeC is based on E-type viscosity meter.

  The content of urethane (meth) acrylate in the above urethane (meth) acrylate composition [II] is preferably 35% by weight or more, particularly preferably 40% by weight or more, still more preferably 45% by weight or more, particularly preferably It is at least 50% by weight, particularly preferably at least 60% by weight. The upper limit is usually 95% by weight.

<Active energy ray curable resin composition>
The active energy ray curable resin composition of the present invention comprises the above urethane (meth) acrylate composition [I] and the urethane (meth) acrylate composition [II]. The content ratio ([I] / [II]) of the urethane (meth) acrylate composition [I] to the urethane (meth) acrylate composition [II] is 90/10 to 10/90 by weight ratio It is preferably 87/13 to 20/80, more preferably 85/15 to 30/70, particularly preferably 80/20 to 55/45. When the content ratio is too small, the flexibility tends to decrease, and when it is too large, the hardness tends to be insufficient.

  It is preferable that the active energy ray curable resin composition (hereinafter sometimes abbreviated as "resin composition") of the present invention further contain a photopolymerization initiator (D). In addition, other urethane (meth) acrylates, ethylenic unsaturated monomers other than urethane (meth) acrylates, acrylic resins, surface conditioners, leveling agents, polymerization inhibitors and the like may be added without impairing the effects of the present invention. In addition, fillers, dyes, pigments, oils, plasticizers, waxes, desiccants, dispersants, wetting agents, gelling agents, stabilizers, antifoaming agents, surfactants, leveling agents, and imparting thixotropy Agents, antioxidants, flame retardants, antistatic agents, fillers, reinforcing agents, matting agents, crosslinking agents, silica, water-dispersed or solvent-dispersed silica, zirconium compounds, preservatives, etc. is there.

  Examples of the photopolymerization initiator (D) include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyl dimethyl ketal, 4- (2-hydroxyethoxy) phenyl- (2) -Hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl phenyl ketone, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy -1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl} -2-methyl-propane, 2-methyl-2-morpholino (4-thiomethylphenyl) propane-1 -One, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone, 2-hydroxy-2 Acetophenones such as methyl-1- [4- (1-methylvinyl) phenyl] propanone oligomer; benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether; benzophenone, o-benzoyl Methyl benzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, 3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, 2,4,6-trimethylbenzophenone , 4-Benzoyl-N, N-dimethyl-N- [2- (1-oxo-2-propenyloxy) ethyl] benzenemetanaminium bromide, benzopheno such as (4-benzoylbenzyl) trimethylammonium chloride and the like 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, 2- (3-dimethylamino-2-hydroxy) -3 Thioxanthones such as 2,4-dimethyl-9H-thioxanthone-9-one meso chloride; 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl -Acyl phosphine oxides such as pentyl phosphine oxide and bis (2,4,6-trimethyl benzoyl) -phenyl phosphine oxide; 1.2-octanedione, 1- [4- (phenylthio)-, 2- ( o-Benzoyl oxime)] Symesters etc. are mentioned. In addition, only 1 type of these photoinitiators (D) may be used independently, and 2 or more types may be used together.

  Among these, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, benzoyl isopropyl ether, 4- (2-hydroxyethoxy) -phenyl (2-hydroxy-2-propyl) ketone, 2-hydroxy-2-methyl-1- It is preferred to use phenylpropan-1-one.

  Moreover, as these auxiliary agents, for example, triethanolamine, triisopropanolamine, 4,4'-dimethylaminobenzophenone (Michler's ketone), 4,4'-diethylaminobenzophenone, 2-dimethylaminoethylbenzoic acid, 4-dimethylamino Ethyl benzoate, 4-Dimethylaminobenzoic acid (n-butoxy) ethyl, 4-Dimethylaminobenzoic acid isoamyl, 4-Dimethylaminobenzoic acid 2-ethylhexyl, 2,4-diethylthioxanthone, 2,4-diisopropylthio It is also possible to use xanthone etc. in combination. These can be used alone or in combination of two or more.

  The content of the photopolymerization initiator (D) is preferably 0.1 to 20 parts by weight, particularly preferably 0.5 to 10 parts by weight, per 100 parts by weight of the curing component contained in the resin composition. Parts by weight, more preferably 1 to 10 parts by weight. If the content of the photopolymerization initiator (D) is too small, curing tends to be poor and film formation tends to be difficult, and if too large, it causes yellowing of the cured coating film and tends to cause coloring problems.

  Examples of ethylenically unsaturated monomers other than urethane (meth) acrylates include monofunctional monomers, bifunctional monomers, and trifunctional or higher polyfunctional monomers. These can be used alone or in combination of two or more.

  Examples of such monofunctional monomers include styrene-based monomers such as styrene, vinyl toluene, chlorostyrene, α-methylstyrene, methyl (meth) acrylate, ethyl (meth) acrylate, acrylonitrile, 2-methoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, phenoxyethyl (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2-hydroxy -3-Phenoxypropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, glycidyl (meth) acrylate, lauryl (meth) acrylate , Cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyl oxyethyl (meth) acrylate, dicyclopentanyl (meth) acrylate , (2-methyl-2-ethyl-1,3-dioxolan-4-yl) -methyl (meth) acrylate, cyclohexane spiro-2- (1,3-dioxolan-4-yl) -methyl (meth) acrylate, 3-ethyl-3-oxetanylmethyl (meth) acrylate, γ-butyrolactone (meth) acrylate, n-butyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) ) Ak Rate, decyl (meth) acrylate, isodecyl (meth) acrylate, dodecyl (meth) acrylate, n-stearyl (meth) acrylate, benzyl (meth) acrylate, phenol ethylene oxide modified (n = 2) (meth) acrylate, nonylphenol propylene Half (meth) acrylates of phthalic acid derivatives such as oxide-modified (n = 2.5) (meth) acrylates, 2- (meth) acryloyloxyethyl acid phosphates, 2- (meth) acryloyloxy-2-hydroxypropyl phthalates, Furfuryl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, carbitol (meth) acrylate, benzyl (meth) acrylate, butoxyethyl (meth) acrylate, allyl (meth) (Meth) acrylate monomers such as acrylate, (meth) acryloyl morpholine, polyoxyethylene secondary alkyl ether acrylate, 2-hydroxyethyl acrylamide, N-methylol (meth) acrylamide, N-vinyl pyrrolidone, 2-vinyl pyridine And vinyl acetate.

  As such a bifunctional monomer, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, di Propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene oxide modified bisphenol A type di (meth) acrylate, propylene oxide modified bisphenol A Type di (meth) acrylate, cyclohexane dimethanol di (meth) acrylate, ethoxylated cyclohexane dimethanol di ( ) Acrylate, dimethylol dicyclopentadi (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) Acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, phthalic acid diglycidyl ester di (meth) acrylate, hydroxypivalic acid modified neopentyl glycol di (meth) acrylate, ethylene isocyanurate An oxide modified diacrylate etc. are mentioned.

  Examples of such trifunctional or higher functional monomers include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa ( Meta) acrylate, tri (meth) acryloyloxy ethoxy trimethylol propane, glycerin polyglycidyl ether poly (meth) acrylate, isocyanurate ethylene oxide modified triacrylate, caprolactone modified dipentaerythritol penta (meth) acrylate, caprolactone modified dipentaerythritol hexamer (Meth) acrylate, caprolactone modified pentaerythritol tri (meth) acrylate, capro Kton modified pentaerythritol tetra (meth) acrylate, ethylene oxide modified dipentaerythritol penta (meth) acrylate, ethylene oxide modified dipentaerythritol hexa (meth) acrylate, ethylene oxide modified pentaerythritol tri (meth) acrylate, ethylene oxide modified pentaerythritol Tetra (meth) acrylate, ethoxylated 15 glycerin triacrylate and the like can be mentioned.

  Also, a Michael adduct of acrylic acid or 2-acryloyloxyethyl dicarboxylic acid monoester can be used in combination, and such a Michael adduct of acrylic acid includes (meth) acrylic acid dimer, trimer of (meth) acrylic acid, (meth) acrylic acid (meth) And acrylic acid tetramers and the like. The 2-acryloyloxyethyl dicarboxylic acid monoester is a carboxylic acid having a specific substituent, and examples thereof include 2-acryloyloxyethyl succinic acid monoester, 2-methacryloyloxyethyl succinic acid monoester, and 2-acryloyloxy. Ethyl phthalic acid monoester, 2-methacryloyloxyethyl phthalic acid monoester, 2-acryloyloxyethyl hexahydrophthalic acid monoester, 2-methacryloyloxyethyl hexahydrophthalic acid monoester, etc. may be mentioned. Furthermore, other oligoester acrylates and the like can be mentioned.

  The content of the ethylenically unsaturated monomer other than urethane (meth) acrylate is preferably 60% by weight or less, particularly preferably 55% by weight or less, based on the total curing components contained in the resin composition. Is 50% by weight or less. The lower limit is usually 5% by weight.

  Examples of the surface conditioner include cellulose resin and alkyd resin. The cellulose resin has an effect of improving the surface smoothness of the coating film, and the alkyd resin has an effect of providing a film forming property at the time of coating. These can be used alone or in combination of two or more.

  As the leveling agent, any generally known leveling agent can be used as long as it has the action of imparting wettability to the substrate of the coating liquid and the action of lowering surface tension. For example, silicone modified resin, fluorine modified resin And alkyl-modified resins can be used. These can be used alone or in combination of two or more.

  As the polymerization inhibitor, the same ones as used in the reaction can be used. For example, p-benzoquinone, naphthoquinone, toluquinone, 2,5-diphenyl-p-benzoquinone, hydroquinone, 2,5-di- Quinones such as t-butyl hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether, mono-t-butyl hydroquinone, etc., aromatics such as 4-methoxyphenol, 2,6-di-t-butyl cresol, p-t-butyl catechol Etc. can be mentioned. These can be used alone or in combination of two or more.

  Moreover, in the active energy ray-curable resin composition of the present invention, it is also preferable to use an organic solvent for dilution in order to make the viscosity at the time of coating appropriate. Such organic solvents include, for example, alcohols such as methanol, ethanol, propanol, n-butanol and i-butanol, ketones such as acetone, methyl isobutyl ketone, methyl ethyl ketone and cyclohexanone, cellosolves such as ethyl cellosolve, toluene and xylene And aromatic ethers such as, glycol ethers such as propylene glycol monomethyl ether, acetates such as methyl acetate, ethyl acetate and butyl acetate, and diacetone alcohol. These organic solvents may be used alone or in combination of two or more.

  When two or more types are used in combination, a combination of a glycol ether such as propylene glycol monomethyl ether and a ketone such as methyl ethyl ketone or an alcohol such as methanol, a ketone such as methyl ethyl ketone and an alcohol such as methanol It is preferable from the viewpoint of the coating film appearance to select and use two or more of the combinations and alcohols such as methanol.

  The active energy ray-curable resin composition of the present invention is effectively used as a curable composition for forming a coating film, such as a top coat agent and an anchor coat agent for various substrates. Then, after the active energy ray-curable resin composition is applied to the substrate (when the resin composition diluted with an organic solvent is applied, after further drying), the active energy ray is irradiated. Be cured.

  Examples of the substrate to which the active energy ray-curable resin composition of the present invention is applied include polyolefin resins, polyester resins, polycarbonate resins, acrylonitrile butadiene styrene copolymer (ABS), and polystyrene resins. Plastic substrates such as resins, etc. and molded products thereof (films, sheets, cups, etc.), optical films such as polyethylene terephthalate film, triacetyl cellulose film, cycloolefin film, composite substrates thereof, glass fibers, etc. Composite substrates of the above materials mixed with inorganic substances, metals (aluminum, copper, iron, SUS, zinc, magnesium, alloys of these, etc.) and glass, or substrates with a primer layer provided on these substrates, etc. Can be mentioned.

  As a coating method of the active energy ray curable resin composition of the present invention, for example, wet coating methods such as spray, shower, gravure, dipping, roll, spin, screen printing and the like can be mentioned. And coating on a substrate.

  Moreover, the active energy ray curable resin composition of the present invention may be coated as it is, or may be diluted with an organic solvent and coated. In the case of dilution, the above-mentioned organic solvent is used to dilute so that the solid concentration is usually 3 to 70% by weight, preferably 5 to 60% by weight.

  As drying conditions at the time of dilution with the organic solvent, the temperature is usually 40 to 120 ° C., preferably 50 to 100 ° C., and the drying time is usually 1 to 20 minutes, preferably 2 to 10 minutes. Just do it.

When coating the active energy ray-curable resin composition of the present invention, the viscosity at 20 ° C. of the resin composition is preferably 5 to 50,000 mPa · s, particularly preferably 10 to 10,000 mPa · s. s, more preferably 50 to 5,000 mPa · s. If the viscosity is outside the above range, the coatability tends to decrease.
In addition, the measuring method of the viscosity in said 20 degreeC is based on a Brookfield viscometer. However, when measurement with a B-type viscometer at 20 ° C. can not be performed because of high viscosity without solvent dilution, measurement is performed using an E-type viscometer at 60 ° C.

  As an active energy ray used when hardening the active energy ray curable resin composition coated on the base material, for example, light rays such as far ultraviolet rays, ultraviolet rays, near ultraviolet rays, infrared rays, X rays, γ rays and the like In addition to the electromagnetic waves described above, electron beams, proton beams, neutron beams and the like can be used, but curing by ultraviolet irradiation is advantageous in view of curing speed, availability of an irradiation apparatus, cost and the like. In addition, when performing electron beam irradiation, it may harden | cure, even if it does not use a photoinitiator (D).

When curing by ultraviolet irradiation, a high pressure mercury lamp, an ultra high pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, a chemical lamp, an electrodeless discharge lamp, an LED lamp, etc. emitting light in the 150 to 450 nm wavelength region Generally, ultraviolet light of 30 to 3,000 mJ / cm ² , preferably 100 to 1,500 mJ / cm ² may be irradiated.
After irradiation with ultraviolet light, heating may be performed as necessary to complete curing.

  The coating film thickness (film thickness after curing) is usually 1 to 1,000 μm in view of light transmission so that the photopolymerization initiator (D) reacts uniformly as an active energy ray curable coating film. And preferably 2 to 500 μm, and particularly preferably 3 to 200 μm.

  The active energy ray-curable resin composition of the present invention is preferably used as a coating agent, and particularly preferably used as a coating agent for hard coat or a coating agent for optical film.

In the present invention, the active energy ray-curable resin composition is applied to a polyethylene terephthalate (PET) film having a size of 15 cm × 15 cm and a thickness of 100 μm so that the coating after curing has a thickness of 10 μm, After drying at a temperature of 60 ° C for 3 minutes, prepare a 80 W high-pressure mercury lamp at a height of 18 cm from the PET film surface, and make the integrated irradiation amount 500 mJ / cm ² at a speed of 5.1 m / min. By irradiation with ultraviolet light, a cured coating is obtained. The cured coating is cut out so as to be 10 cm × 10 cm, and the coating which becomes the cured coating having an average value of the bounce heights of four corners of the cut cured coating is 40 mm or less, particularly 30 mm or less, further 25 mm or less It is preferable to use an agent.

In the present invention, the active energy ray-curable resin composition is applied to an easy-adhesion PET film having a size of 15 cm × 15 cm and a thickness of 125 μm so that the coating after curing has a thickness of 10 μm. After drying for 3 minutes at ° C, prepare a 80 W high-pressure mercury lamp at a height of 18 cm from the easy-adhesion PET film surface, and make the cumulative irradiation amount 500 mJ / cm ² at a speed of 5.1 m / min. By irradiation with ultraviolet light, a cured coating is obtained. In the cured coating film, the flexibility is evaluated using a cylindrical mandrel bending tester according to JIS K 5600-5-1, and the cured coating film for evaluation is cracked or peeled off when wound around a test rod. It is preferable to use a coating agent having a maximum diameter (integer value, mm) at which 20 occurs at 20 mm or less, particularly 15 mm or less, further 10 mm or less, particularly 8 mm or less.

  The present invention provides (meth) acrylates (a1) to (a3) in a mixture (A) of the following (meth) acrylates (a1) to (a4), which are reaction products of pentaerythritol and (meth) acrylic acid; Urethane (meth) acrylate composition [I] reacted with polyvalent isocyanate (B), and the following (meth) acrylates (b1) to (b6) which are reaction products of dipentaerythritol and (meth) acrylic acid And a urethane (meth) acrylate composition [II] in which the (meth) acrylates (b1) to (b5) in the mixture (B) and the polyvalent isocyanate (CB) have reacted; Active energy ray curable resin composition wherein the hydroxyl value of (A) is 200 mg KOH / g or more and the hydroxyl value of the mixture (B) is 40 mg KOH / g or more It is. This active energy ray-curable resin composition has the effect of being hard to curl due to small curing shrinkage, and capable of forming a cured coating film excellent in hardness and flexibility, and in particular, a coating agent Is useful as a coating agent for a hard coat or a coating agent for an optical film, and is also useful as a paint, an ink, etc.

  EXAMPLES Hereinafter, the present invention will be more specifically described by way of examples. However, the present invention is not limited to the following examples as long as the gist thereof is not exceeded. In the examples, "parts" and "%" mean weight basis.

  Urethane acrylate composition [I] ([I-1] to [I-3]), [II] ([II-1] to [II-2]), and urethane for comparison as follows. Acrylate compositions [I ′] ([I′-1] to [I′-3]) were prepared.

[Urethane Acrylate Composition [I-1]]
Acrylate mixture (A-1) (pentaerythritol acrylic acid) with 36 g of isophorone diisocyanate (C-1) and a hydroxyl value of 288 mg KOH / g in a four-necked flask equipped with a thermometer, stirrer, water-cooled condenser, and nitrogen gas blowing port Adduct) 64g, 100g of ethyl acetate as solvent, 0.08g of 4-methoxyphenol as polymerization inhibitor, 0.05g of dibutyltin dilaurate as reaction catalyst are charged, reacted at 60 ° C, and the remaining isocyanate group is 0.1% The reaction was terminated when the reaction time reached to obtain a urethane acrylate composition [I-1] (resin concentration: 50%).
The weight average molecular weight of the obtained urethane acrylate composition [I-1] was 4,700, and the viscosity at 20 ° C. was 80 mPa · s. The viscosity at 20 ° C. was measured using a B-type viscometer. The viscosity measurement at 20 ° C. is the same as below.

In addition, the content rate of each component with respect to the sum total of the following component (a1)-(a4) in acrylate mixture (A-1) is as follows.
(A1) pentaerythritol monoacrylate 4%
(A2) pentaerythritol diacrylate 29%
(A3) pentaerythritol triacrylate 49%
(A4) pentaerythritol tetraacrylate 18%

  In addition, the content rate of each component in a mixture is measured by using a column (made by Imtakt, Cadenza CD-C18 100x3 mm 3 micrometers) for liquid chromatograph (made by Agilent, "Technology HP 1100").

[Production of Urethane Acrylate Composition [I-2]]
A four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas inlet, 33 g of hydrogenated xylylene diisocyanate (C-2), and an acrylate mixture (A-1) having a hydroxyl value of 288 mg KOH / g (penta) 67 g of acrylic acid adduct of erythritol, 100 g of ethyl acetate as a solvent, 0.08 g of 4-methoxyphenol as a polymerization inhibitor, 0.05 g of dibutyltin dilaurate as a reaction catalyst, reacted at 60 ° C., residual isocyanate group is 0 The reaction was terminated when it became 1% to obtain a urethane acrylate composition [I-2] (resin content concentration 50%).
The weight average molecular weight of the obtained urethane acrylate composition [I-2] was 6,200, and the viscosity at 20 ° C. was 65 mPa · s.

[Production of Urethane Acrylate Composition [I-3]]
Acrylate mixture (A-1) (acrylic acid of pentaerythritol) with 32 g of xylylene diisocyanate (C-3) and a hydroxyl value of 288 mg KOH / g in a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas blowing port Acid adduct) 68 g, 100 g of ethyl acetate as solvent, 0.08 g of 4-methoxyphenol as polymerization inhibitor, 0.05 g of dibutyltin dilaurate as reaction catalyst are charged, reacted at 60 ° C., residual isocyanate group is 0.1% Reaction was complete | finished when it became, and urethane acrylate type composition [I-3] was obtained (resin part density | concentration 50%).
The weight average molecular weight of the obtained urethane acrylate composition [I-3] was 5,900, and the viscosity at 20 ° C. was 50 mPa · s.

[Production of Urethane Acrylate Composition [II-1]]
In a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas inlet, 27.9 g of hydrogenated xylylene diisocyanate (C-2) and an acrylate mixture (B-1) having a hydroxyl value of 96 mg KOH / g (Acrylic acid adduct of dipentaerythritol) 172.1 g, 0.08 g of 4-methoxyphenol as a polymerization inhibitor, 0.1 g of dibutyltin dilaurate as a reaction catalyst are charged, reacted at 60 ° C., and the remaining isocyanate group is 0. The reaction was terminated when it reached 1% to obtain a urethane acrylate composition [II-1] (resin content concentration 100%).
The weight average molecular weight of the obtained urethane acrylate composition [II-1] was 5,500, and the viscosity at 60 ° C. was 39,400 mPa · s. The viscosity at 60 ° C. was measured using an E-type viscometer. The viscosity measurement at 60 ° C. is the same as below.

In addition, the content rate of each component with respect to the sum total of the following component (b1)-(b6) in acrylate mixture (B-1) is as follows.
(B4) dipentaerythritol tetraacrylate 18%
(B5) dipentaerythritol pentaacrylate 51%
(B6) dipentaerythritol hexaacrylate 31%
However, since the content of (b1) dipentaerythritol monoacrylate, (b2) dipentaerythritol diacrylate, and (b3) dipentaerythritol triacrylate was below the measurement limit value, the inclusion of the components (b4) to (b6) The proportion is shown.

[Production of Urethane Acrylate Composition [II-2]]
Acrylate mixture (B-1) (dipentaerythritol) with 31.3 g of isophorone diisocyanate (C-1) and a hydroxyl value of 96 mg KOH / g in a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas blowing port Of acrylic acid adduct), 0.08 g of 4-methoxyphenol as a polymerization inhibitor, 0.1 g of dibutyltin dilaurate as a reaction catalyst, reacted at 60 ° C., and the remaining isocyanate group becomes 0.1%. The reaction was terminated at the time point, and a urethane acrylate composition [II-2] was obtained (resin content concentration 100%).
The weight average molecular weight of the obtained urethane acrylate composition [II-2] was 67,000, and the viscosity at 60 ° C. was 65,000 mPa · s.

[Production of Urethane Acrylate Composition [II-3]]
In a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas inlet, 13.2 g of isophorone diisocyanate (C-1) and an acrylate mixture (B-2) having a hydroxyl value of 54 mg KOH / g (dipentaerythritol) Of acrylic acid adduct), 0.08 g of 4-methoxyphenol as a polymerization inhibitor, 0.1 g of dibutyltin dilaurate as a reaction catalyst, reacted at 60 ° C., and the remaining isocyanate group becomes 0.1%. At the point of time, the reaction was terminated to obtain a urethane acrylate composition [II-3] (resin content concentration 100%).
The weight average molecular weight of the obtained urethane acrylate composition [II-3] was 2,000, and the viscosity at 60 ° C. was 1,700 mPa · s.

In addition, the content rate of each component with respect to the sum total of the following component (b1)-(b6) in acrylate mixture (B-2) is as follows.
(B4) dipentaerythritol tetraacrylate 6%
(B5) dipentaerythritol pentaacrylate 54%
(B6) Dipentaerythritol hexaacrylate 40%
However, since the content of (b1) dipentaerythritol monoacrylate, (b2) dipentaerythritol diacrylate, and (b3) dipentaerythritol triacrylate was below the measurement limit value, the inclusion of the components (b4) to (b6) The proportion is shown.

[Production of Urethane Acrylate Composition [I'-1]]
Acrylate mixture (A'-1) (pentaerythritol acrylic acid) with 38.4 g of isophorone diisocyanate (C-1) and a hydroxyl value of 118 mg KOH / g in a flask equipped with a thermometer, stirrer, water-cooled condenser, and nitrogen gas blowing port Add 161.6 g of adduct), 0.01 g of hydroquinone methyl ether as a polymerization inhibitor, 0.01 g of dibutyltin dilaurate as a reaction catalyst, and react at 60 ° C. for 8 hours to make the residual isocyanate group not more than 0.3% The reaction was terminated when the reaction time reached to obtain a urethane acrylate compound [I'-1] (resin concentration 100%).
The weight average molecular weight of the resulting urethane acrylate composition [I′-1] was 1,400, and the viscosity at 60 ° C. was 3,000 mPa · s.

In addition, the content rate of each component with respect to the sum total of the following component (a1)-(a4) in acrylate mixture (A'-1) is as follows.
(A2) pentaerythritol diacrylate 5%
(A3) pentaerythritol triacrylate 50%
(A4) pentaerythritol tetraacrylate 45%
However, since the content of the (a1) pentaerythritol monoacrylate was below the measurement limit value, the content ratio of the components (a2) to (a4) was shown.

[Production of Urethane Acrylate Composition [I′-2]]
Acrylate mixture containing 23.3 g of hydrogenated xylylene diisocyanate (C-2) and a hydroxyl value of 184.2 mg KOH / g in a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas blowing port (A ' 2) 76.7 g of (acrylic acid adduct of pentaerythritol), 100 g of ethyl acetate as a solvent, 0.08 g of 4-methoxyphenol as a polymerization inhibitor, 0.05 g of dibutyltin dilaurate as a reaction catalyst and reacting at 60 ° C. The reaction was terminated when the residual isocyanate group reached 0.1%, to obtain a urethane acrylate composition [I'-2] (resin concentration: 50%).
The weight average molecular weight of the obtained urethane acrylate composition [I′-2] was 2,200, and the viscosity at 20 ° C. was 85 mPa · s.

In addition, the content rate of each component with respect to the sum total of the following component (a1)-(a4) in an acrylate mixture (A'-2) is as follows.
(A1) pentaerythritol monoacrylate 1.6%
(A2) pentaerythritol diacrylate 14.6%
(A3) pentaerythritol triacrylate 49.6%
(A4) pentaerythritol tetraacrylate 34.2%

[Production of Urethane Acrylate Composition [I'-3]]
Acrylate mixture (A'-2) (2'5 g of isophorone diisocyanate (C-1), hydroxyl value 184.2 mg KOH / g) in a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas blowing port 74.2 g of acrylic acid adduct of pentaerythritol, 100 g of ethyl acetate as a solvent, 0.08 g of 4-methoxyphenol as a polymerization inhibitor, 0.05 g of dibutyltin dilaurate as a reaction catalyst, reacted at 60 ° C., residual isocyanate The reaction was terminated when the group reached 0.1%, to obtain a urethane acrylate composition [I'-3] (resin concentration: 50%).
The weight average molecular weight of the obtained urethane acrylate composition [I'-3] was 2,100, and the viscosity at 20 ° C. was 73 mPa · s.

<Examples 1 to 8, Comparative Examples 1 to 5>
[Production of Active Energy Ray-Curable Resin Composition]
The urethane acrylate composition ([I], [II], [I ']) obtained above was formulated as shown in Table 1 below, and further, 1- as a photopolymerization initiator (D), An active energy ray curable resin composition was obtained by blending 4 parts of hydroxycyclohexyl phenyl ketone (manufactured by IGM, “Omnirad 184”) with respect to 100 parts of the curing component.

  About the obtained active energy ray curable resin composition, a cured coating film was formed as follows, and the hardness and flexibility of the cured coating film were evaluated. The evaluation results are as shown in Table 1 below.

[Hardness of cured coating]
The active energy ray-curable resin composition obtained above is coated on a substrate for easy bonding PET film (“A4300” manufactured by Toyobo Co., Ltd., size 15 cm × 15 cm, thickness 125 μm) using a bar coater and cured after coating Coated at a thickness of 10 μm and dried at 60 ° C for 3 minutes, then using a high-pressure mercury lamp 80 W, 1 lamp, 2 passes UV irradiation from a height of 18 cm to a conveyor speed of 5.1 m / min A cumulative coating amount of 500 mJ / cm ^{2 was} applied to form a cured coating.
About the said cured coating film coated on the easily bonding PET film, it tested according to JISK-5600, and measured pencil hardness.

[Flexibility of cured coating]
A cured coating film is formed in the same manner as in the above hardness evaluation, and the cured coating film coated on the easy-adhesion PET film is bent using a cylindrical mandrel bending tester according to JIS K 5600-5-1. The sex was evaluated. The largest diameter (integer value, mm) at which cracking or peeling occurs when the cured film for evaluation was wound around a test rod so that the coated film surface was on the outside was measured. The smaller the value is, the more flexible the film is.

From the said evaluation result, the cured coating film obtained from active energy ray curable resin composition containing urethane acrylate type composition [I] and [II] of Examples 1-8 is excellent in both hardness and flexibility. I understand that.
On the other hand, in Comparative Example 1 in which only the urethane acrylate composition [II] was used without containing the urethane acrylate composition [I], the flexibility of the cured coating film was inferior. Furthermore, in Comparative Examples 2 and 3 containing a urethane acrylate composition prepared using an acrylate mixture having a low hydroxyl value, the flexibility of the cured coating was poor.
Moreover, also in Comparative Examples 4 and 5 containing a urethane acrylate composition prepared using an acrylate mixture having a slightly higher hydroxyl value, the flexibility of the cured coating film was inferior.
From these, it can be seen that the active energy ray-curable resin composition of the examples is excellent in hardness and flexibility, and is useful in applications such as a coating agent, particularly a coating agent for hard coating and a coating agent for optical film.

  The active energy ray-curable resin composition of the present invention is less likely to curl due to a small cure shrinkage when forming a cured coating film, and can form a coating film excellent in hardness and flexibility. It is useful as a coating agent, especially a coating agent for hard coat and a coating agent for optical films. It is also useful as a paint, an ink and the like. Furthermore, after the resin composition side of the uncured laminated film in which the active energy ray curable resin composition layer is formed on the film is attached to a molded product, various methods are performed by performing active energy ray curing. A cured film can be easily formed on the molded product of

Claims (12)

(Meth) acrylates (a1) to (a3) in a mixture (A) of the following (meth) acrylates (a1) to (a4), which are the reaction products of pentaerythritol and (meth) acrylic acid; Mixtures of urethane (meth) acrylate compositions [I] reacted with CA) and the following (meth) acrylates (b1) to (b6), which are the reaction products of dipentaerythritol and (meth) acrylic acid ( B) containing (meth) acrylates (b1) to (b5) and a urethane (meth) acrylate composition [II] in which a polyvalent isocyanate (CB) is reacted, and the above mixture (A) Active energy ray curability characterized by a hydroxyl value of 200 mg KOH / g or more and a hydroxyl value of the mixture (B) of 40 mg KOH / g or more Fat composition.
Mixture (A)
(A1) pentaerythritol mono (meth) acrylate (a2) pentaerythritol di (meth) acrylate (a3) pentaerythritol tri (meth) acrylate (a4) pentaerythritol tetra (meth) acrylate mixture (B)
(B1) dipentaerythritol mono (meth) acrylate (b2) dipentaerythritol di (meth) acrylate (b3) dipentaerythritol tri (meth) acrylate (b4) dipentaerythritol tetra (meth) acrylate (b5) dipentaerythritol Penta (meth) acrylate (b6) dipentaerythritol hexa (meth) acrylate   The content ratio of pentaerythritol di (meth) acrylate (a2) in the mixture (A) of the (meth) acrylates (a1) to (a4) is 10 to 50% by weight. Active energy ray curable resin composition.   3. The active energy ray according to claim 1, wherein the content ratio of pentaerythritol di (meth) acrylate (a2) to the total of (meth) acrylates (a1) to (a3) is 15 to 55% by weight. Curable resin composition.   The weight average molecular weight of said urethane (meth) acrylate type composition [I] is 1,000-20,000, The active energy ray curability as described in any one of Claims 1-3 characterized by the above-mentioned. Resin composition.   The content ratio of dipentaerythritol penta (meth) acrylate (b5) in the mixture (B) of the (meth) acrylates (b1) to (b6) is 15 to 60% by weight. 4. Active energy ray curable resin composition as described in any one of 4.   The content ratio of dipentaerythritol penta (meth) acrylate (b5) with respect to the said (meth) acrylate (b1)-(b5) total is 45 to 90 weight%, Any one of the Claims 1-5 characterized by the above-mentioned. The active energy ray curable resin composition as described in a term.   The content ratio of dipentaerythritol tetra (meth) acrylate (b4) in the mixture (B) of the (meth) acrylates (b1) to (b6) is 1 to 35% by weight. 6. Active energy ray curable resin composition as described in any one of 6.   The content ratio of dipentaerythritol tetra (meth) acrylate (b4) with respect to the said (meth) acrylate (b1)-(b5) total is 2-40 weight%, Any one of the Claims 1-7 characterized by the above-mentioned. The active energy ray curable resin composition as described in a term.   The weight average molecular weight of said urethane (meth) acrylate type composition [II] is 1,000-20,000, The active energy ray curability as described in any one of Claims 1-8 characterized by the above-mentioned. Resin composition.   A coating agent comprising the active energy ray curable resin composition according to any one of claims 1 to 9.   The coating agent according to claim 10, which is used as a coating agent for hard coating.   The coating agent according to claim 10, which is used as a coating agent for an optical film.