JP7207972B2 - Curable resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a curable resin composition and a method for producing a three-dimensional object using the same.

As an example of the application of the liquid curable resin composition, the curable resin composition is cured layer by layer with light such as ultraviolet light, and the layers are sequentially laminated to produce a desired three-dimensional object. method (stereolithography method) has been earnestly studied. The use of stereolithography is not limited to the production of prototypes for shape confirmation (rapid prototyping), but is expanding to the production of working models and molds for functional verification (rapid tooling). In addition, the use of stereolithography is expanding to the modeling of actual products (rapid manufacturing).
Against this background, demands for curable resin compositions are becoming more sophisticated. Recently, there is a demand for a curable resin composition capable of forming a three-dimensional object having high mechanical properties (strength, rigidity, toughness, etc.) comparable to those of general-purpose engineering plastics. The thermal stability and mechanical properties such as toughness of the cured product largely depend on the chemical structure of the compounds contained in the resin composition. For example, it is generally well known that having a rigid structure gives a cured product with excellent heat resistance, and having a flexible structure gives a cured product with excellent toughness, and many studies have been made so far.
Patent Document 1 describes an epoxy resin composition having a rigid aromatic ring and a flexible alkylene group in its chemical structure, and the cured product of this resin composition is flexible and has high toughness. A cured product can be obtained. Patent Document 2 describes an oxetane composition having a rigid aromatic ring in its chemical structure, and this resin composition has good curability and can give a cured product with good adhesion. Patent Document 3 describes a method of using an epoxy or oxetane compound having a rigid aromatic ring such as naphthalene or biphenyl as a curable resin composition for prepreg. The curable resin composition has a fast curing rate and can produce prepregs with excellent thermal and mechanical properties. Patent Document 4 describes a resin composition in which an oxetane compound having a rigid aromatic ring and an epoxy compound, particularly an epoxy compound having a rigid aromatic ring such as bisphenol, are mixed. A cured product obtained by curing this resin composition with an ultraviolet ray or the like can accurately obtain a cured product having a high aspect ratio with little sink marks during curing. In addition, the cured product has a high refractive index and can be used for optical elements.

Japanese Patent No. 04815877 JP 2009-191129 A WO2007/034679 JP 2008-184563 A

However, it is difficult to achieve both heat resistance and toughness in a cured product, and a cured product with sufficiently satisfactory mechanical properties has not been obtained. The cured product of the epoxy resin composition having a flexible skeleton described in Patent Document 1 has excellent toughness, but does not have sufficiently high heat resistance. On the other hand, the cured products of the resin compositions having rigid skeletons described in Patent Documents 2 to 4 are excellent in heat resistance, but not sufficiently high in toughness.
Therefore, in order to solve the above-described problems, an object of the present invention is to provide a curable resin composition that achieves both toughness and heat resistance compared to conventional compositions.

The curable resin composition of the present invention is
(A) a curable resin represented by the following general formula (1);

［Ｘ₁、Ｘ₂は、独立に、ジフェニルメタンジイル基、ジフェニルプロパンジイル基、ビフェニレン基またはジフェニルエーテルジイル基である。
Ｘ₃は、炭素数４以上１８以下のアルキレン基である。
Ｌ₁、Ｌ ₂ は、独立に、下記一般式（１－ｇ）で表される２価の連結基である。

［ｐ、ｑは独立に０以上５以下の整数である。
＊は、Ｘ ₁ 、Ｘ ₂ 、Ｘ ₃ との結合手を表す。］
Ｌ ₃ 、Ｌ ₄ は、独立に、下記一般式（１－ｄ）で表される２価の連結基である。

［ｇ、ｈは独立に０以上５以下の整数である。
＊は、Ｙ ₁ 、Ｙ ₂ 、Ｘ ₁ 、Ｘ ₂ との結合手を表す。］
Ｙ₁、Ｙ₂は、独立に、エポキシ基、シクロアルケンオキシド基またはオキセタニル基である。
ｎは繰り返し構造単位の平均値であり、０．１以上１０以下の実数である。］
（Ｂ）下記一般式（２）に示されるオキセタン化合物と、

[X ₁ and X ₂ are independently a diphenylmethanediyl group, a diphenylpropanediyl group, a biphenylene group, or a diphenyletherdiyl group .
X ₃ is an alkylene group having 4 to 18 carbon atoms .
L ₁ and L ₂ are independently divalent linking groups represented by the following general formula (1-g) .

[p and q are independently integers of 0 to 5;
* represents a bond with X ₁ , X ₂ and X ₃ . ]
L ₃ and L ₄ are each independently a divalent linking group represented by general formula (1-d) below.

[g and h are independently integers of 0 to 5;
* represents a bond with Y ₁ , Y ₂ , X ₁ and X ₂ . ]
Y ₁ and Y ₂ are independently an epoxy group, a cycloalkene oxide group or an oxetanyl group.
n is the average value of repeating structural units and is a real number of 0.1 or more and 10 or less. ]
(B) an oxetane compound represented by the following general formula (2);

［Ｘ₄は、置換基を有してもよい、フェニレン基、ビフェニレン基、ナフタレンジイル基、アントラセンジイル基、フェナントレンジイル基、フルオレンジイル基、ジフェニルメタンジイル基、ジフェニルエタンジイル基、ジフェニルプロパンジイル基、ジフェニルエーテルジイル基、ジフェニルスルホンジイル基、トリフェニルエタンジイル基またはテトラフェニルメタンジイル基である。
Ｘ₅、Ｘ₆は、独立に、水素原子あるいは炭素数１以上６以下のアルキル基である。
Ｌ₅、Ｌ₆は、独立に、下記一般式（１－ａ）または（１－ｄ）で表される２価の連結基である。

［ａ、ｂ、ｇ、ｈは独立に０以上５以下の整数である。
＊は、Ｘ ₄ 、隣接する炭素原子との結合手を表す。］
ｓは、繰り返し構造単位の平均値であり、０．１以上１０以下の実数である。］
（Ｃ）カチオン重合性開始剤と、
を含有し、前記硬化性樹脂（Ａ）と前記オキセタン化合物（Ｂ）の質量比が、５：５乃至９：１であることを特徴とする。

[X ₄ is a phenylene group, biphenylene group, naphthalenediyl group, anthracenediyl group, phenanthenediyl group, fluorenediyl group, diphenylmethanediyl group, diphenylethanediyl group, diphenylpropanediyl group, which may have a substituent; , a diphenyletherdiyl group, a diphenylsulfonediyl group, a triphenylethanediyl group or a tetraphenylmethanediyl group .
X ₅ and X ₆ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
L ₅ and L ₆ are each independently a divalent linking group represented by general formula (1-a) or (1-d) below .

[a, b, g, and h are independently integers of 0 to 5;
* represents X ₄ , a bond with an adjacent carbon atom. ]
s is the average value of repeating structural units and is a real number of 0.1 or more and 10 or less. ]
(C) a cationic polymerization initiator ;
and the mass ratio of the curable resin (A) and the oxetane compound (B) is 5:5 to 9:1.

According to the curable resin composition of the present invention, it is possible to provide a resin cured product having both higher toughness and heat resistance than conventional ones.

Embodiments of the present invention will be described below. The embodiment described below is merely one of the embodiments of the present invention, and the present invention is not limited to these embodiments.

<Curable Resin (A) (Component (A))>
The curable resin (A) used in the present invention is represented by the following general formula (1).

In general formula (1) above, X ₁ and X ₂ are each independently a divalent linking group containing an aromatic ring. X ₁ and X ₂ preferably contain two or less aromatic rings from the viewpoint of availability and solubility in solvents. If the number of aromatic rings is 2 or less, problems in synthesis reactions such as increased crystallinity and poor solubility in solvents are less likely to occur. X ₁ and X ₂ are connecting groups that connect to the adjacent group (L ₁ , L ₂ , L ₃ , L ₄ ) at the carbon atoms that constitute the aromatic ring, and the adjacent groups at atoms other than the carbon atoms that constitute the aromatic ring. Although it may be a linking group that links with , a linking group that links with an adjacent group via a carbon atom that constitutes an aromatic ring is preferable.

Examples of X ₁ and X ₂ include a hydrocarbon group having a structure having only one aromatic ring, a hydrocarbon group having a structure in which an aromatic ring is bonded via a single bond, and an aromatic ring via an aliphatic carbon atom. A hydrocarbon group having a structure in which an aromatic ring is bonded via an aliphatic cyclic hydrocarbon group, a hydrocarbon group having a structure in which multiple benzene rings are condensed and polycyclic, an aromatic ring is bonded through an aralkyl group, and a hydrocarbon group having a structure in which an aromatic ring is bonded through an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom. For example, specifically, phenylene group, biphenylene group, naphthalenediyl group, anthracenediyl group, phenanthenediyl group, fluorenediyl group, diphenylmethanediyl group, diphenylethanediyl group, diphenylpropanediyl group, diphenyletherdiyl group, diphenylsulfone A diyl group and the like can be mentioned. These may be unsubstituted or may have a substituent. Examples of substituents which may be present include linear or branched alkyl groups having 1 to 6 carbon atoms.

From the viewpoint of the excellent balance of flexibility and toughness of the cured product obtained from the curable resin composition of the present invention, and from the viewpoint of light transmission, in particular, a diphenylmethanediyl group (general formula (1-I)), A diphenylpropanediyl group (general formula (1-II)), a biphenylene group (general formula (1-III)), and a diphenyletherdiyl group ((general formula (1-IV))) are preferred, and these may be unsubstituted or substituted. You may have a group. Examples of substituents which may be present include linear or branched alkyl groups having 1 to 6 carbon atoms.

[* represents a bond with L ₁ , L ₂ , L ₃ and L ₄ . ]

X ₃ is an alkylene group having 4 to 18 carbon atoms, preferably 4 to 12 carbon atoms, more preferably 4 to 10 carbon atoms. If the number of carbon atoms is 3 or less, flexibility is impaired and sufficient toughness cannot be exhibited. On the other hand, when the number of carbon atoms is 19 or more, the hardness of the cured product is lowered, resulting in impaired heat resistance. Specific examples of X3 include a butylene group _, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, a decanylene group, a dodecanylene group, a tridecanylene group, a tetradecanylene group, a pentadecanylene group, a hexadecanylene group, and a heptadecanylene group. linear or branched acyclic alkylene group such as octadecanylene group, cyclobutylene group, cyclopentylene group, cyclohexylene group, cycloheptylene group, cyclooctylene group, bicyclic, tricyclic and polycyclic alkylene groups, which may be unsubstituted or have a substituent. Examples of substituents which may be present include linear or branched alkyl groups having 1 to 6 carbon atoms. Among these, from the viewpoint of availability, it is preferably an acyclic alkylene group having a linear or branched structure having 4 to 12 carbon atoms, more preferably a linear alkylene group having 4 to 10 carbon atoms. is a non-cyclic acyclic alkylene group.

In X ₃ , the carbon atoms constituting the alkylene group may be replaced with an oxygen atom, sulfur atom, nitrogen atom or silicon atom, and have a repeating structure such as oxymethylene, oxyethylene, oxypropylene, etc. Also good. In this case, the number of unsubstituted carbon atoms is preferably 4 or more and 10 or less.

As X ₃ , an alkylene group represented by the following general formula (1-VII) is preferable from the viewpoint of compatibility between hydrophobicity and toughness and heat resistance, and an alkylene group represented by general formula (1-VIII) improves toughness. It is more preferable from the point of view.

[l is an integer of 4 or more and 18 or less, preferably 4 or more and 10 or less.

R ₁ and R ₂ are hydrogen or methyl groups. m is an integer selected so that the number of carbon atoms is 4 or more and 18 or less, preferably 4 or more and 10 or less.

* represents a bond with L ₁ and L ₂ . ]

L ₁ , L ₂ , L ₃ and L ₄ are independently -O-, -C-O-, -S-, -C-S-, ester bond, urethane bond, ether bond, thiourethane bond and thioether It is a divalent linking group containing one or more bonds selected from the group consisting of bonds. Hereinafter, "a bond selected from the group consisting of -O-, -C-O-, -S-, -C-S-, an ester bond, a urethane bond, an ether bond, a thiourethane bond and a thioether bond" is referred to as a "specific may be referred to as "bonding". L ₁ to L ₄ may be a linking group that directly connects to the adjacent group (Y ₁ , Y ₂ , X ₁ , X ₂ , X ₃ ) via a specific bond, or may be a linking group that links to via one or more carbon atoms. When a specific bond is -O-, -C-O-, -S-, or -C-S-, the oxygen atom or sulfur atom of the specific bond is interposed between the specific bond and the adjacent group. It is preferable to bond with the carbon atom of the group or the carbon atom of the adjacent group to form an ether bond or a thioether bond.

When L ₁ to L ₄ contain one or two bonds selected from the group consisting of -O-, -CO-, -S-, -C-S-, an ether bond and a thioether bond, curability This is preferable because it facilitates rotational movement of the molecular chains of the resin (A) and increases the effect of improving toughness. If the number of bonds selected from the group consisting of -O-, -CO-, -S-, -CS-, an ether bond and a thioether bond is two or less, the motility does not excessively increase, The heat resistance of the cured product can be maintained.

Moreover, it is preferable for L ₁ to L ₄ to have a hydroxyl group because it has the effect of promoting the polymerization reaction of the curable resin (A). The number of hydroxyl groups is preferably 6 or less per molecule of the curable resin (A). If the number of hydroxyl groups is 6 or less in one molecule, the curable resin composition and the cured product thereof will not increase in water absorption and will have stability over time.

L ₁ , L ₂ , L ₃ and L ₄ are, for example, specifically represented by the following general formulas (1-a), (1-b), (1-c), (1-d), ( Groups represented by 1-e), (1-f) and (1-g) are preferred. In particular, the groups represented by general formulas (1-a), (1-d), (1-e), (1-f), and (1-g) are preferred from the viewpoint of material availability and synthesis efficiency. more preferred. Furthermore, groups represented by general formulas (1-d), (1-e), (1-f), and (1-g) are more preferable from the viewpoint of improving toughness. Also, the group represented by the general formula (1-g) is preferable from the viewpoint of promoting the polymerization reaction of the curable resin (A).

[a, b, c, d, e, f, g, h, i, j, k, o, p, q are independently integers of 0 to 5, and the flexibility and composition of the cured product of the composition An integer of 0 or more and 2 or less is preferable from the viewpoint of the viscosity of the product, and an integer of 0 or more and 1 or less is more preferable from the viewpoint of maintaining the heat resistance.

* represents a bond with Y ₁ , Y ₂ , X ₁ , X ₂ and X ₃ . ]

Y ₁ and Y ₂ are polymerizable groups and independently epoxy groups, cycloalkene oxide groups or oxetanyl groups. The cycloalkene oxide group includes a cyclopropene oxide group, a cyclobutene oxide group, a cyclopentene oxide group, a cyclohexene oxide group, a cycloheptene oxide group, and the like. Specifically, Y ₁ and Y ₂ are preferably represented by the following general formulas (1-h), (1-i) and (1-j), respectively, from the standpoint of ease of synthesis and availability.

[R ₃ and R ₄ are independently hydrogen or an alkyl group having 1 to 4 carbon atoms, and from the viewpoint of polymerizability and availability, hydrogen or an alkyl group having 1 to 2 carbon atoms. is preferred, and hydrogen is more preferred.
* is a bond with L ₃ and L ₄ . ]

n represents the average value of repeating structural units and is a real number of 0.1 or more and 10 or less. In order to suppress the increase in viscosity of the composition, n is preferably in the range of 0.2 or more and 5 or less, and more preferably in the range of 0.5 or more and 3 or less from the viewpoint of the balance of toughness and heat resistance of the cured product.

As the curable resin (A), commercially available products such as EPICLON EXA-4816 (manufactured by DIC), EPICLON EXA-4850-150 (manufactured by DIC), and EPICLON EXA-4850-1000 (manufactured by DIC) are suitable. can be used for

As a specific example of the curable resin (A), a curable resin represented by the following structure is preferred from the viewpoint of achieving both toughness and heat resistance, and n=1 is more preferred. Moreover, when it has a hydroxyl group, it is more preferable that it has an effect of accelerating the curing of the curable resin (A).

From the viewpoint of improving the toughness of the cured product, the curable resin (A) is used so that the mass ratio of the component (A) and the component (B) is 5:5 to 9:1, preferably 7:3 to 9:1. contained in That is, the content of the curable resin (A) is 50 parts by mass or more and 90 parts by mass or less, preferably 70 parts by mass or more and 90 parts by mass or less with respect to a total of 100 parts by mass of the component (A) and the component (B). be.

(Method for producing curable resin (A))
The method for producing the curable resin (A) is not particularly limited. For example, a diglycidyl ether compound (A-1) and an aromatic dihydroxy compound (A-2) are reacted to obtain a dihydroxy compound. (A-3) is obtained. Then, the halogen group of the cationically polymerizable compound having a halogen group is allowed to react with the hydroxyl group of the dihydroxy compound (A-3) to obtain the curable resin (A).

Examples of the diglycidyl ether compound (A-1) include compounds represented by the following general formula (3). X ₃ corresponds to X ₃ in general formula (1), the details of which are as described for general formula (1). The diglycidyl ether compound (A-1) may be used alone or in combination of two or more.

Examples of compounds represented by the general formula (3) include 1,4-butanediol diglycidyl ether, diethylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, 1,7 -heptanediol diglycidyl ether, 1,8-octanediol diglycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether, tripropylene glycol diglycidyl ether, 1,9-nonanediol diglycidyl ether, 1,10-decane Diol diglycidyl ether, 1,11-undecanediol diglycidyl ether, 1,12-dodecanediol diglycidyl ether, 1,18-stearyldiol diglycidyl ether and the like can be mentioned.

Examples of aromatic dihydroxy compounds (A-2) include compounds represented by the following general formula (4). X ₇ corresponds to X ₁ and X ₂ in general formula (1), the details of which are as described for general formula (1).

Examples of compounds represented by general formula (4) include 1,4-dihydroxybenzene, catechol, 4,4′-dihydroxydiphenylmethane, 4,4′-methylenebis(2,6-dimethylphenol), 2,2 -bis(4-hydroxyphenyl)propane, 2,2'-methylenebis(4-methylphenol), 4,4'-ethylidenebisphenol, 4,4'-dihydroxybenzophenone, 4,4'-(1,3-dimethyl butylidene)diphenol, 4,4'-(α-methylbenzylidene)bisphenol, 4,4'-(α-methylbenzylidene)bisphenol, 4,4'-dihydroxytetraphenylmethane, 2,7-naphthalenediol, 2 , 3-naphthalenediol, 2,6-anthracenediol, and the like.

A cationically polymerizable compound having a halogen group is a compound having an epoxy group, a cycloalkene oxide group, or an oxetanyl group and a halogen group such as —I, —Br, and —Cl. Specific examples include 2-(chloromethyl)-1,2-epoxypropane and 2-(chloromethyl)-1,2-epoxybutane.

As another production method, a bifunctional phenol compound, which is an aromatic dihydroxy compound, is reacted with divinyl ether. Then, a cationically polymerizable compound having a halogen group is reacted with the obtained bifunctional phenol resin to obtain a curable resin (A).

<Oxetane compound (B) (component (B))>
The oxetane compound (B) is represented by the following general formula (2), is a compound having at least two oxetanyl groups, and is polymerized by the curing agent (C) described below.

The oxetane compound (B) may be composed of only one type of oxetane compound, or may be composed of a plurality of types of oxetane compounds.

The number of oxetanyl groups possessed by the oxetane compound (B) is not particularly limited. Examples of the oxetane compound (B) include bifunctional oxetane compounds having two oxetanyl groups in the molecule, trifunctional oxetane compounds having three oxetanyl groups in the molecule, and tetrafunctional compounds having four or more oxetanyl groups in the molecule. Examples include, but are not limited to, the oxetane compounds described above. Among these, bifunctional oxetane compounds having two oxetanyl groups in the molecule are preferred.

In the above general formula (2), X ₄ is a divalent linking group linking via carbon atoms constituting the aromatic ring. Examples of X ₄ include a hydrocarbon group having a structure having only one aromatic ring, a hydrocarbon group having a structure in which an aromatic ring is bonded via a single bond, and a hydrocarbon group in which an aromatic ring is bonded via an aliphatic carbon atom. A hydrocarbon group consisting of a structure, a hydrocarbon group consisting of a structure in which an aromatic ring is bonded via an aliphatic cyclic hydrocarbon group, a hydrocarbon group consisting of a structure in which multiple benzene rings are condensed and polycyclic, and an aromatic ring is an aralkyl group and a hydrocarbon group having a structure in which an aromatic ring is bonded via an oxygen atom or a sulfur atom. Specific examples include a phenylene group, a biphenylene group, a naphthalenediyl group, an anthracenediyl group, a phenanthenediyl group, a fluorenediyl group, a diphenylmethanediyl group, a diphenylethanediyl group, a diphenylpropanediyl group, a diphenyletherdiyl group, and a diphenylsulfone. A diyl group, a triphenylethanediyl group, a tetraphenylmethanediyl group, and the like can be mentioned, and these may be unsubstituted or may have a substituent. Examples of substituents which may be present include linear or branched alkyl groups having 1 to 6 carbon atoms. Among these, a phenylene group, a biphenylene group or a diphenylmethanediyl group, which may have a substituent, is preferable. X ₄ may have a group containing an oxetanyl group.

X ₅ and X ₆ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Specific examples of alkyl groups having 1 to 6 carbon atoms represented by X ₅ and X ₆ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, Non-cyclic alkyl groups such as s-butyl group, t-butyl group, pentyl group and hexyl group; cyclic alkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group and cyclohexyl group; Among these, methyl group and ethyl group are preferred.

L ₅ and L ₆ are each independently a divalent linking group containing a bond selected from the group consisting of —O—, —CO—, ester bond and ether bond. Hereinafter, "a bond selected from the group consisting of -O-, -C-O-, an ester bond and an ether bond" may be referred to as a "second specific bond". L ₅ and L ₆ may be a linking group that directly connects to the adjacent group (methylene group, X ₄ ) via the second specific bond, or one or more may be a linking group that links via the carbon atom of When the second specific bond is either -O- or -C-O-, the oxygen atom of the second specific bond is the carbon atom intervening between the second specific bond and the adjacent group or It is preferred to combine with the carbon atoms of adjacent groups to form an ether bond. Specific examples of L ₅ and L ₆ include those represented by the general formulas (1-a) and (1-d). L ₅ and L ₆ may have a group containing an oxetanyl group.

The average value of the repeating structural units represented by s is a real number of 0.1 or more and 10 or less, preferably 0.2 or more and 5 or less from the viewpoint of the toughness of the cured product, and from the viewpoint of the viscosity of the oxetane compound (B) , more preferably 0.5 or more and 3 or less.

As the oxetane compound (B), commercially available products such as ETERNACOLL (R) OXBP (manufactured by Ube Industries, Ltd.), ETERNACOLL (R) OXIPA (manufactured by Ube Industries, Ltd.), and Aron Oxetane OXT-121 (manufactured by Toagosei Co., Ltd.) are preferably used. can be used.

As a specific example of the oxetane compound (B), a compound represented by the following structure is preferable from the viewpoint of achieving both toughness and heat resistance.

From the viewpoint of improving the toughness of the cured product, the curable resin (A) is used so that the mass ratio of the component (A) and the component (B) is 5:5 to 9:1, preferably 7:3 to 9:1. contained in That is, the content of the oxetane compound (B) is 10 parts by mass or more and 50 parts by mass or less, preferably 10 parts by mass or more and 30 parts by mass or less with respect to a total of 100 parts by mass of the component (A) and the component (B). .

<Curing Agent (C) (Component (C))>
As the curing agent (C), cationic polymerization initiators such as photoacid generators, photobase generators and thermal acid generators can be used. These may be used singly or in combination as long as the effects of the present invention are not impaired. When forming a three-dimensional object by photocuring, it is preferable to use a photoacid generator or a photobase generator due to the stability of the curable resin composition of the present invention over time and the limitations of the three-dimensional modeling method. , it is particularly preferred to use a photoacid generator. Further, as the curing agent (C), other curing agents such as radical polymerization initiators such as heat latent curing agents may be contained.

[Cationic polymerization initiator]
(Photoacid generator)
The photoacid generator is a photocationically polymerizable initiator that generates an acid capable of initiating cationic polymerization by irradiation with energy rays such as ultraviolet rays. When used as a curable resin for three-dimensional modeling, it is preferable to use a photocationically polymerizable initiator.

Examples of photocationically polymerizable initiators include, for example, the cationic moiety of which is aromatic sulfonium, aromatic iodonium, aromatic diazonium, aromatic ammonium, thianthrenium, thioxanthonium, (2,4-cyclopentadien-1-yl ) [(1-methylethylbenzene]-Fe cation, and the anion moiety is BF ₄ ^- , PF ₆ ^- , SbF ₆ ^- , [BX ₄ ] ^- , where X is at least two fluorines or trifluoromethyl An onium salt composed of a phenyl group substituted with a group) can be used alone or in combination of two or more.

Examples of aromatic sulfonium salts include bis[4-(diphenylsulfonio)phenyl]sulfide bishexafluorophosphate, bis[4-(diphenylsulfonio)phenyl]sulfide bishexafluoroantimonate, bis[4-(diphenylsulfonio) nio)phenyl]sulfide bistetrafluoroborate, bis[4-(diphenylsulfonio)phenyl]sulfidetetrakis(pentafluorophenyl)borate, diphenyl-4-(phenylthio)phenylsulfonium hexafluorophosphate, diphenyl-4-(phenylthio) Phenylsulfonium hexafluoroantimonate, Diphenyl-4-(phenylthio)phenylsulfonium tetrafluoroborate, Diphenyl-4-(phenylthio)phenylsulfonium tetrakis(pentafluorophenyl)borate, Triphenylsulfonium hexafluorophosphate, Triphenylsulfonium hexafluoroantimonate triphenylsulfonium tetrafluoroborate, triphenylsulfonium tetrakis(pentafluorophenyl)borate, bis[4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl]sulfide bishexafluorophosphate, bis[ 4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl]sulfide bishexafluoroantimonate, bis[4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl]sulfide Bis-tetrafluoroborate, bis[4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl]sulfide tetrakis(pentafluorophenyl)borate and the like can be used.

Examples of aromatic iodonium salts include diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, diphenyliodonium tetrafluoroborate, diphenyliodonium tetrakis(pentafluorophenyl)borate, bis(dodecylphenyl)iodonium hexafluorophosphate, bis (dodecylphenyl)iodonium hexafluoroantimonate, bis(dodecylphenyl)iodonium tetrafluoroborate, bis(dodecylphenyl)iodonium tetrakis(pentafluorophenyl)borate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexa fluorophosphate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluoroantimonate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrafluoroborate, 4-methylphenyl-4-( 1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate and the like can be used.

As the aromatic diazonium salt, for example, phenyldiazonium hexafluorophosphate, phenyldiazonium hexafluoroantimonate, phenyldiazonium tetrafluoroborate, phenyldiazonium tetrakis(pentafluorophenyl)borate and the like can be used.

Further, aromatic ammonium salts include 1-benzyl-2-cyanopyridinium hexafluorophosphate, 1-benzyl-2-cyanopyridinium hexafluoroantimonate, 1-benzyl-2-cyanopyridinium tetrafluoroborate, 1-benzyl- 2-cyanopyridinium tetrakis(pentafluorophenyl)borate, 1-(naphthylmethyl)-2-cyanopyridinium hexafluorophosphate, 1-(naphthylmethyl)-2-cyanopyridinium hexafluoroantimonate, 1-(naphthylmethyl)- 2-Cyanopyridinium tetrafluoroborate, 1-(naphthylmethyl)-2-cyanopyridinium tetrakis(pentafluorophenyl)borate and the like can be used.

Thianthrenium salts include 5-methylthianthrenium hexafluorophosphate, 5-methyl-10-oxothianthenium tetrafluoroborate, 5-methyl-10,10-dioxothianthrenium hexafluorophosphate, and the like. can be used.

As the thioxanthonium salt, S-biphenyl 2-isopropylthioxanthonium hexafluorophosphate and the like can be used.

Further, as the (2,4-cyclopentadien-1-yl)[(1-methylethyl)benzene]-Fe salt, (2,4-cyclopentadien-1-yl)[(1-methylethylbenzene]-Fe (II) hexafluorophosphate, (2,4-cyclopentadien-1-yl)[(1-methylethylbenzene]-Fe(II) hexafluoroantimonate, (2,4-cyclopentadien-1-yl)[( 1-methylethylbenzene]-Fe(II) tetrafluoroborate, (2,4-cyclopentadien-1-yl)[(1-methylethylbenzene]-Fe(II) tetrakis(pentafluorophenyl)borate, etc. can be done.

Examples of photocationic polymerization initiators include CPI (R)-100P, CPI (R)-110P, CPI (R)-101A, CPI (R)-200K, and CPI (R)-210S (San-Apro Co., Ltd. ), Cyracure (R) photo-curing initiator UVI-6990, Cyracure (R) photo-curing initiator UVI-6992, Cyracure (R) photo-curing initiator UVI-6976 (manufactured by Dow Chemical Japan), Adeka Optomer SP-150, Adeka Optomer SP-152, Adeka Optomer SP-170, Adeka Optomer SP-172, Adeka Optomer SP-300 (manufactured by ADEKA Co., Ltd.), CI-5102, CI-2855 (Above, manufactured by Nippon Soda Co., Ltd.), San-Aid (R) SI-60L, San-Aid (R) SI-80L, San-Aid (R) SI-100L, San-Aid (R) SI-110L, San-Aid (R) SI-180L , San-Aid (R) SI-110, San-Aid (R) SI-180 (manufactured by Sanshin Chemical Industry Co., Ltd.), Esacure (R) 1064, Esacure (R) 1187 (manufactured by Lamberti), Omnicat 550 (manufactured by IGM Resin), Irgacure (R) 250 (manufactured by BASF), Rhodosyl Photoinitiator 2074 (RHODORSILPOTOINITIATOR 2074 (manufactured by Rhodia Japan), etc. are commercially available.

In the present invention, two or more photocationic polymerization initiators may be used in combination, or may be used alone. In addition, other curing agents such as a thermal cationic polymerization initiator may be contained at the same time in order to advance the polymerization reaction by heat treatment after modeling.

The amount of the photoacid generator to be added is preferably 0.1 parts by mass or more and 15 parts by mass or less, more preferably 0.1 parts by mass or more with respect to a total of 100 parts by mass of the component (A) and the component (B). It is 10 parts by mass or less. If the amount of the photoacid generator is small, the polymerization tends to be insufficient. If the amount of initiator is too high, the light transmission may be reduced and the polymerization may be non-uniform.

(Photobase generator)
A photobase generator refers to a compound that generates a base upon irradiation with energy rays such as ultraviolet rays and visible light. In particular, a salt containing a borate anion is preferred because of its good sensitivity to light. Specific products include U-CAT 5002 manufactured by San-Apro Co., Ltd., and P3B, BP3B, N3B, and MN3B manufactured by Showa Denko K.K., but are not limited to these.

The amount of the photobase generator added is preferably 0.1 parts by mass or more and 15 parts by mass or less, more preferably 0.1 parts by mass or more, with respect to a total of 100 parts by mass of the component (A) and the component (B). It is 10 parts by mass or less. If the amount of photobase generator is small, the polymerization tends to be insufficient.

(Thermal acid generator)
A thermal acid generator is also called a thermal cationic polymerization initiator. A compound containing a cationic species is excited by heating, a thermal decomposition reaction occurs, and it exhibits a substantial function as a curing agent that advances thermal curing. Thermal cationic polymerization initiators, unlike acid anhydrides, amines, phenolic resins, etc., which are generally used as curing agents, even if they are contained in the resin composition, It does not cause viscosity increase or gelation. Therefore, it is possible to provide a one-component resin composition with excellent handleability.

Thermal cationic polymerization initiators include, for example, diphenyliodonium hexafluoroarsenate, diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, triphenylsulfonium tetrafluoroborate, tri-p-tolylsulfonium hexafluorophosphate, tri-p-tolylsulfonium trifluoromethanesulfonate, bis(cyclohexylsulfonyl)diazomethane, bis(tert-butylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, triphenylsulfonium trifluoromethanesulfonate, diphenyl-4-methylphenyl sulfonium trifluoromethanesulfonate, diphenyl-2,4,6-trimethylphenylsulfonium-p-toluenesulfonate, diphenyl-p-phenylthiophenylsulfonium hexafluorophosphate and the like.

In the present invention, as a thermal cationic polymerization initiator, for example, diazonium salt compounds AMERICURE series (manufactured by American Can), ULTRASET series (manufactured by ADEKA), WPAG series (manufactured by Wako Pure Chemical Industries, Ltd.), iodonium salt-based Compounds UVE series (manufactured by General Electric Co.), FC series (manufactured by 3M), UV9310C (manufactured by GE Toshiba Silicone), WPI series (manufactured by Wako Pure Chemical Industries), CYRACURE series of sulfonium salt compounds (Union Carbide), UVI series (manufactured by General Electric), FC series (manufactured by 3M), CD series (manufactured by Sartomer), Optomer SP series, Optomer CP series (manufactured by Adeka), San-Aid SI series (Sanshin) Chemical Industry Co., Ltd.), CI series (Nippon Soda Co., Ltd.), WPAG series (Wako Pure Chemical Industries, Ltd.), CPI series (San-Apro Co., Ltd.), and other commercially available products can be used.

In the present invention, two or more thermal cationic polymerization initiators may be used in combination, or may be used alone. A thermal cationic polymerization initiator that decomposes at a high temperature may also be used in order to advance the polymerization reaction by heat treatment after modeling.

The amount of the thermal acid generator to be added is preferably 0.1 parts by mass or more and 15 parts by mass or less, more preferably 0.1 parts by mass or more with respect to a total of 100 parts by mass of the component (A) and the component (B). It is 10 parts by mass or less. If the amount of the thermal acid generator is too small, the polymerization tends to be insufficient.

[Radical polymerization initiator]
In the present invention, a radical polymerization initiator may be contained particularly when the radically polymerizable compound (E) is contained.

Radical polymerization initiators are mainly classified into intramolecular cleavage type and hydrogen abstraction type. In an intramolecularly cleavable radical polymerization initiator, absorption of light of a specific wavelength cuts a bond at a specific site, generating a radical at the cut site, which becomes a polymerization initiator and is radically polymerizable. Polymerization of compound (E) begins. On the other hand, in the case of the hydrogen abstraction type, it absorbs light of a specific wavelength and becomes an excited state, and the excited species causes a hydrogen abstraction reaction from the surrounding hydrogen donor, generating radicals, which act as polymerization initiators and radicals. Polymerization of the polymerizable compound (E) begins.

As the intramolecular cleavage type photoradical polymerization initiator, an alkylphenone photoradical polymerization initiator, an acylphosphine oxide photoradical polymerization initiator, and an oxime ester photoradical polymerization initiator are known. These are of the type in which the bond adjacent to the carbonyl group undergoes α-cleavage to generate a radical species. Examples of the alkylphenone-based radical photopolymerization initiator include benzylmethylketal-based radical photopolymerization initiators, α-hydroxyalkylphenone-based radical photopolymerization initiators, and aminoalkylphenone-based radical photopolymerization initiators. Specific compounds include, for example, benzyl methyl ketal photoradical polymerization initiators such as 2,2′-dimethoxy-1,2-diphenylethan-1-one (Irgacure (R) 651, manufactured by BASF). 2-hydroxy-2-methyl-1-phenylpropan-1-one (Darocure (R) 1173, manufactured by BASF) and 1-hydroxycyclohexylphenyl ketone as α-hydroxyalkylphenone photoradical polymerization initiators. (Irgacure (R) 184, manufactured by BASF), 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one (Irgacure (R) 2959, manufactured by BASF) ), 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropan-1-one (Irgacure (R) 127, manufactured by BASF), etc. , and the aminoalkylphenone photoradical polymerization initiator includes 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one (Irgacure (R) 907, manufactured by BASF) or 2 -benzylmethyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone (Irgacure (R) 369, manufactured by BASF) and the like, but are not limited thereto. Acylphosphine oxide-based photoradical polymerization initiators include 2,4,6-trimethylbenzoyldiphenylphosphine oxide (lucirin (R) TPO, manufactured by BASF) and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide. (Irgacure (R) 819, manufactured by BASF) and the like, but are not limited to these. As the oxime ester photoradical polymerization initiator, (2E)-2-(benzoyloxyimino)-1-[4-(phenylthio)phenyl]octan-1-one (Irgacure (R) OXE-01, manufactured by BASF Corporation ), etc., but not limited to these.

Hydrogen abstraction type radical polymerization initiators include anthraquinone derivatives such as 2-ethyl-9,10-anthraquinone and 2-t-butyl-9,10-anthraquinone, and thioxanthone derivatives such as isopropylthioxanthone and 2,4-diethylthioxanthone. Examples include, but are not limited to.

In the present invention, two or more photoradical polymerization initiators may be used in combination, or may be used alone. In addition, a thermal radical polymerization initiator may be contained in order to advance the polymerization reaction by heat treatment after modeling.

The amount of the radical photopolymerization initiator to be added is preferably 0.1 parts by mass or more and 15 parts by mass or less, more preferably 0.1 parts by mass or more and 10 parts by mass with respect to 100 parts by mass of the radically polymerizable compound (E). It is below. If the amount of photoradical polymerization initiator is small, polymerization tends to be insufficient. If the amount of initiator is too high, the light transmission may be reduced and the polymerization may be non-uniform.

Further, the thermal radical polymerization initiator is not particularly limited as long as it generates radicals by heating, and conventionally known compounds can be used. Examples include azo compounds, peroxides and persulfates. can be exemplified as preferable. Azo compounds include 2,2'-azobisisobutyronitrile, 2,2'-azobis(methyl isobutyrate), 2,2'-azobis-2,4-dimethylvaleronitrile, 1,1'- and azobis(1-acetoxy-1-phenylethane). Examples of peroxides include benzoyl peroxide, di-t-butylbenzoyl peroxide, t-butyl peroxypivalate and di(4-t-butylcyclohexyl)peroxydicarbonate. Persulfates include persulfates such as ammonium persulfate, sodium persulfate and potassium persulfate.

The amount of the thermal radical polymerization initiator to be added is preferably 0.1 parts by mass or more and 15 parts by mass or less, more preferably 0.1 parts by mass or more and 10 parts by mass, relative to 100 parts by mass of the radically polymerizable compound (E). It is below. If the polymerization initiator is excessively added, the molecular weight cannot be extended and the physical properties may deteriorate.

[Other curing agents]
As the curing agent (C), the following thermal latent curing agents can be used. A heat-latent curing agent refers to a curing agent that advances thermal curing by heating.

As the acid anhydride (acid anhydride-based curing agent), a known or commonly used acid anhydride-based curing agent can be used, and is not particularly limited. 3-methyltetrahydrophthalic anhydride, etc.), methylhexahydrophthalic anhydride (4-methylhexahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride, etc.), dodecenyl succinic anhydride, methylendomethylenetetrahydrophthalic anhydride, Phthalic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylcyclohexenedicarboxylic anhydride, pyromellitic anhydride, trimellitic anhydride, benzophenonetetracarboxylic anhydride, nadic anhydride, methyl nadic anhydride , hydrogenated methylnadic anhydride, 4-(4-methyl-3-pentenyl)tetrahydrophthalic anhydride, succinic anhydride, adipic anhydride, sebacic anhydride, dodecanedioic anhydride, methylcyclohexenetetracarboxylic anhydride, vinyl ether-maleic anhydride copolymers, alkylstyrene-maleic anhydride copolymers, and the like. Among them, acid anhydrides that are liquid at 25° C. [eg, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, dodecenylsuccinic anhydride, methylendomethylenetetrahydrophthalic anhydride, etc.] are preferred from the viewpoint of handling. On the other hand, for an acid anhydride that is solid at 25°C, for example, by dissolving it in an acid anhydride that is liquid at 25°C to form a liquid mixture, the curing agent (C ) tends to be easier to handle. As the acid anhydride-based curing agent, an anhydride of a saturated monocyclic hydrocarbon dicarboxylic acid (including an anhydride having a substituent such as an alkyl group bonded to the ring) is preferable from the viewpoint of heat resistance and transparency of the cured product.

As amines (amine-based curing agents), known or commonly-used amine-based curing agents can be used without particular limitation, but examples include ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenediamine, and diethylaminopropylamine. , aliphatic polyamines such as polypropylenetriamine; alicyclic polyamines such as bis(3-aminopropyl)-3,4,8,10-tetraoxaspiro[5,5]undecane; m-phenylenediamine, p-phenylenediamine, tolylene-2,4-diamine, Mononuclear polyamines such as tolylene-2,6-diamine, mesitylene-2,4-diamine, 3,5-diethyltolylene-2,4-diamine, 3,5-diethyltolylene-2,6-diamine, biphenylene Aromatic polyamines such as diamine, 4,4-diaminodiphenylmethane, 2,5-naphthylenediamine, 2,6-naphthylenediamine, and the like are included.

Phenols (phenol-based curing agents) can be known or commonly used phenol-based curing agents, and are not particularly limited. Aralkyl resins such as resins, terpene-modified phenol resins, dicyclopentadiene-modified phenol resins, triphenol propane and the like can be mentioned.

Polyamide resins include, for example, polyamide resins having either or both of a primary amino group and a secondary amino group in the molecule.

As imidazoles (imidazole-based curing agents), known or commonly used imidazole-based curing agents can be used without particular limitation. Examples include 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecyl imidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2-methylimidazolium isocyanurate, 2-phenylimidazolium isocyanurate, 2,4-diamino -6-[2-methylimidazolyl-(1)]-ethyl-s-triazine, 2,4-diamino-6-[2-ethyl-4-methylimidazolyl-(1)]-ethyl-s-triazine and the like mentioned.

Examples of polymercaptans (polymercaptan-based curing agents) include liquid polymercaptans and polysulfide resins.

Examples of polycarboxylic acids include adipic acid, sebacic acid, terephthalic acid, trimellitic acid, and carboxy group-containing polyesters.

The amount of the other curing agent added is preferably 0.1 parts by mass or more and 75 parts by mass or less, more preferably 5 parts by mass or more and 30 parts by mass, based on a total of 100 parts by mass of component (A) and component (B). It is below. If the amount of the thermal latent polymerization initiator is too small, the polymerization tends to be insufficient, and if it is too large, the cross-linking reaction will proceed and the toughness will tend to deteriorate.

<Cationically polymerizable compound (D) (component (D))>
The curable resin composition of the present invention may contain, for example, an epoxy resin, an oxetane compound, etc., as cationic polymerizable compounds other than the components (A) and (B).

[Epoxy resin]
Epoxy resins other than component (A) used in the present invention include bisphenol A type epoxy resin, bisphenol F type epoxy resin, biphenyl type epoxy resin, tetramethylbiphenyl type epoxy resin, naphthalene type epoxy resin, phenol novolac type epoxy resin, Cresol novolak type epoxy resin, triphenylmethane type epoxy resin, tetraphenylethane type epoxy resin, dicyclopentadiene-phenol addition reaction type epoxy resin, phenol aralkyl type epoxy resin, naphthol novolac type epoxy resin, naphthol aralkyl type epoxy resin, naphthol -Phenol cocondensed novolak type epoxy resin, naphthol-cresol cocondensed novolak type epoxy resin, aromatic hydrocarbon formaldehyde resin modified phenol resin type epoxy resin, biphenyl modified novolak type epoxy resin, naphthylene ether type epoxy resin and the like.

These epoxy resins may be oligomerized as multimers, but in the case of a photocurable resin that can be suitably used in the present invention, the crystallinity is low and it is difficult to solidify, but the cured product tends to be hard. A bisphenol type epoxy resin is preferred. Among bisphenol-type epoxy resins, monomers such as bisphenol A diglycidyl ether and bisphenol F diglycidyl ether are desirable because the viscosity of the photocurable resin composition is low.

The epoxy resin of the present invention preferably has an aromatic ring in order to improve the hardness of the cured product.

[Oxetane compound]
Oxetane compounds other than component (A) and component (B) used in the present invention include oxetane compounds having one oxetanyl group, oxetane compounds having two or more oxetanyl groups and no aromatic ring, and the like. The oxetane compound may be composed of only one type of oxetane compound, or may be composed of a plurality of oxetane compounds. It is not particularly limited as long as it is a compound having an oxetanyl group.

Specific examples of oxetane compounds include 3-ethyl-3-[(2-ethylhexyloxy)methyl]oxetane, 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3-(4-hydroxybutyl ) oxymethyloxetane, 3-ethyl-3-hexyloxymethyloxetane, 3-ethyl-3-allyloxymethyloxetane, 3-ethyl-3-benzyloxymethyloxetane, 3-ethyl-3-methacryloxymethyloxetane, 3 -monooxetane compounds such as ethyl-3-carboxyoxetane and 3-ethyl-3-phenoxymethyloxetane; bis[1-ethyl(3-oxetanyl)]methyl ether, bis[(ethyl(3-oxetanyl)]methyl carbonate, bis[ethyl(3-oxetanyl)]ethyl adipate, bis[ethyl(3-oxetanyl)]methyl 1,4-cyclohexanecarboxylate, α,ω-bis-{3-[1-ethyl(3-oxetanyl)methoxy ] dioxetane compounds such as propyl(polydimethylsiloxane), and polyvalent oxetane compounds such as oligo(glycidyloxetane-co-ethylglycidylether), but are not limited thereto.

Among them, 3-ethyl-3-[(2-ethylhexyloxy)methyl]oxetane, 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3-[(2-ethylhexyloxy)methyl]oxetane, 3- Ethyl-3-(4-hydroxybutyl)oxymethyloxetane, bis[1-ethyl(3-oxetanyl)]methyl ether are preferred.

As the oxetane compound, a commercially available product containing a cationic polymerizable monomer as a main component can be used. (manufactured by Ube Industries, Ltd.), ETERNACOLL (R) OXTP (manufactured by Ube Industries, Ltd.), and the like.

[Content of cationic polymerizable compound (D)]
The content of the cationic polymerizable compound (D) is preferably 0.1 parts by mass or more and 75 parts by mass or less, and 5 parts by mass or more and 30 parts by mass or less with respect to a total of 100 parts by mass of the component (A) and the component (B). is more preferred.

<Radical Polymerizable Compound (E) (Component (E))>
The curable resin composition of the present invention may contain, for example, a (meth)acrylate compound as the radically polymerizable compound (E).

The (meth) acrylate compound includes monofunctional (meth) acrylate compounds having one (meth) acryloyl group in the molecule, polyfunctional (meth) acrylate compounds having two or more (meth) acryloyl groups, and the like. be done. In the present invention, any polymerizable (meth)acrylic compound that can be polymerized by a general method can be used. A monofunctional (meth)acrylate compound and a polyfunctional (meth)acrylate compound can be used by arbitrarily mixing one or more of them.

Monofunctional (meth)acrylate compounds include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth) Acrylate, n-octyl (meth)acrylate, i-octyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, 2- Hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, glycidyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, phenyl glycidyl (meth)acrylate, dimethylaminomethyl (meth)acrylate, phenylcellosolve (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, biphenyl (meth)acrylate, 2-hydroxyethyl ( meth)acryloyl phosphate, phenyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxypropyl (meth)acrylate, benzyl (meth)acrylate and the like.

Polyfunctional (meth)acrylate compounds include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, nonaethylene glycol di(meth) acrylates, 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, dimethyloltricyclodecane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, neopentyl glycol di( meth)acrylate, 1,6-hexamethylene di(meth)acrylate, hydroxypivalic acid ester neopentyl glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetraacrylate , dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tris(meth)acryloxyethyl isocyanurate, and the like.

For exhibiting the effects of the present invention, the content of the radically polymerizable compound (E) is preferably 0 parts by mass or more and 75 parts by mass or less with respect to a total of 100 parts by mass of the component (A) and the component (B). If the amount of the radically polymerizable compound (E) is excessive, the effects of the present invention may be impaired.

<Other ingredients>
The curable resin composition of the present invention may contain various additives as other optional components within a range that does not impair the object and effect of the present invention. Examples of such additives include resins such as epoxy resins, polyurethanes, polybutadiene, polychloroprene, polyesters, styrene-butadiene block copolymers, polysiloxanes, petroleum resins, xylene resins, ketone resins, cellulose resins, polycarbonates, and modified polyphenylene ethers. , polyamide, polyacetal, polyethylene terephthalate, polybutylene terephthalate, ultra-high molecular weight polyethylene, polyphenylsulfone, polysulfone, polyarylate, polyetherimide, polyetheretherketone, polyphenylene sulfide, polyethersulfone, polyamideimide, liquid crystal polymer, polytra Engineering plastics such as fluoroethylene, polychlorotrifluoroethylene, and polyvinylidene fluoride, reactive monomers such as fluorine-based oligomers, silicone-based oligomers, polysulfide-based oligomers, fluorine-containing monomers, and siloxane structure-containing monomers, and soft materials such as gold, silver, and lead Layered crystal structure substances such as metals, graphite, molybdenum disulfide, tungsten disulfide, boron nitride, graphite fluoride, calcium fluoride, barium fluoride, lithium fluoride, silicon nitride, molybdenum selenide, phenothiazine, 2,6- Polymerization inhibitors such as di-t-butyl-4-methylphenol, photosensitizers such as benzoin compounds, acetophenone compounds, anthraquinone compounds, thioxanthone compounds, ketal compounds, benzophenone compounds, tertiary amine compounds, and xanthone compounds, polymerization Initiation aids, leveling agents, wettability improvers, surfactants, plasticizers, UV absorbers, silane coupling agents, inorganic fillers, pigments, dyes, antioxidants, flame retardants, thickeners, antifoaming agents etc. can be mentioned.

<Curable resin composition>
The composition of the present invention is prepared by charging appropriate amounts of the essential components (A), (B) and (C) and, if necessary, other optional components into a stirring vessel, and the It can be produced by stirring at 50°C or higher and 100°C or lower. The stirring time at that time is usually 1 minute or more and 6 hours or less, preferably 10 minutes or more and 2 hours or less. The total content of component (A) and component (B) is preferably 1 part by mass or more and 100 parts by mass or less, more preferably 25 parts by mass with respect to 100 parts by mass of the curable resin composition excluding component (C). The effects of the present invention can be sufficiently obtained when the content is 100 parts by mass or more, more preferably 75 parts by mass or more and 100 parts by mass or less.

The viscosity of the composition of the present invention at 25° C. is preferably 50 mPa·s or more and 10,000 mPa·s or less, more preferably 70 mPa·s or more and 5,000 mPa·s or less.

The composition of the present invention obtained as described above is suitably used as a photocurable resin composition in optical stereolithography. That is, by selectively irradiating the photocurable resin composition of the present invention with active energy rays such as ultraviolet rays, electron beams, X-rays, and radiation to supply the energy necessary for curing, , a three-dimensional object having a desired shape can be manufactured.

<Cured product>
The composition of the present invention comprises a curable resin (A), an oxetane compound (B) and a curing agent (C) as essential components, and a cured product can be obtained by curing these. Curing can be performed using any known method such as active energy ray curing or heat curing depending on the curing agent to be contained. A plurality of curing methods may be combined.

<Function of curable resin composition>
The curable resin composition of the present invention can be cured by applying external energy to form a cured product. At this time, the cationic polymerization reaction of the curable resin (A) and the oxetane compound (B) is initiated by the acid or the like generated by the curing agent (C), and the curing of the curable resin composition proceeds. Here, in order to improve the curability and heat resistance of the cured product, it is preferable that the crosslink density in the cured product is high. However, since the cross-linking points in the cured product are physically fixed, if the cross-linking density is too high, the toughness will be significantly reduced and the product will become brittle. On the other hand, in the curable resin composition according to the present embodiment, the molecular skeletons of the curable resin (A) and the oxetane compound (B) always contain an aromatic ring. Therefore, a weak interaction between the aromatic rings, so-called π-π stacking, works between the molecules of the curable resin (A) and the oxetane compound (B), and this contributes to the improvement of curability and heat resistance like a cross-linking point. As a result, the resin composition of the present invention can provide a cured product having higher toughness than conventional ones while maintaining heat resistance equivalent to that of conventional curable resin compositions.

<Manufacturing method of three-dimensional object>
The curable resin composition of the present invention contains a photoacid generator or a photobase generator as the curing agent (C), so that it can be suitably used in an optical stereolithography method. A cured product of the curable resin composition may be produced using any conventionally known optical stereolithography method and apparatus. A preferred representative example of the three-dimensional optical modeling method is a method comprising the step of photocuring a curable resin composition layer by layer based on slice data to form a modeled object. Specifically, based on the slice data, active energy rays are selectively irradiated to form a cured layer so that a cured layer having a desired pattern is obtained in a liquid curable resin composition. Next, an uncured curable resin composition is supplied to this cured layer, and an active energy beam is similarly irradiated based on the slice data to form a new cured layer continuous with the cured layer. A method of finally obtaining a desired three-dimensional model by repeating this lamination operation can be mentioned.

Examples of active energy rays used in this case include ultraviolet rays, electron beams, X-rays, and radiation. Among them, ultraviolet light having a wavelength of 300 nm or more and 450 nm or less is preferably used from an economical point of view. As a light source at that time, an ultraviolet laser (for example, Ar laser, He--Cd laser, etc.), a mercury lamp, a xenon lamp, a halogen lamp, a fluorescent lamp, or the like can be used. Among them, a laser light source is preferably employed because it can shorten the modeling time by increasing the energy level, and has excellent light-gathering properties to obtain high modeling accuracy.

When forming each cured resin layer having a predetermined shape pattern by irradiating an active energy ray onto a molding surface made of a curable resin composition, an active energy ray focused into dots such as a laser beam is used. The cured resin layer may be formed by stippling or line drawing. In addition, there is a molding method in which active energy rays are applied to the molding surface through a planar drawing mask formed by arranging a plurality of minute light shutters such as liquid crystal shutters or digital micromirror shutters to form a cured resin layer. may be adopted.

A representative example of the optical stereolithography method is as follows. First, the resin composition is supplied onto the support stage by dropping (sedimenting) a small amount (sedimentation) from the liquid surface of the resin composition on the support stage, which is provided to be able to move up and down in the container, to form a thin layer (1) of the resin composition. to form Next, by selectively irradiating the thin layer (1) with light, a solid cured resin layer (1) is formed. Next, a curable resin composition is supplied onto the cured resin layer (1) to form the thin layer (2), and the thin layer (2) is selectively irradiated with light to obtain a cured resin. A new cured resin layer (2) is formed on layer (1) so that it is continuously and integrally laminated therewith. Then, by repeating this process a predetermined number of times while changing or not changing the light irradiation pattern, a three-dimensional structure in which a plurality of cured resin layers (1, 2, . . . n) are integrally laminated. A molded object is molded.

The three-dimensional object thus obtained is removed from the container, and after removing the unreacted curable resin composition remaining on the surface thereof, the object is washed as necessary. Examples of cleaning agents include alcohol-based organic solvents typified by alcohols such as isopropyl alcohol and ethyl alcohol; ketone-based organic solvents typified by acetone, ethyl acetate, and methyl ethyl ketone; and aliphatic solvents typified by terpenes. system organic solvents. In addition, after cleaning with a cleaning agent, post-curing by light irradiation or heat irradiation may be performed as necessary. Post-cure can cure the unreacted curable resin composition that may remain on the surface and inside of the three-dimensional object, and in addition to suppressing the stickiness of the surface of the three-dimensional object, the initial strength of the object can be improved.

<Application>
Applications of the curable resin composition according to the present invention and its cured product are not particularly limited. For example, it can be used for various applications such as resins for stereolithography 3D printers, sporting goods, medical and nursing care products, industrial machinery and equipment, precision equipment, electrical and electronic equipment, electrical and electronic parts, and building materials. be.

Examples are given below to describe the present invention in detail, but the present invention is not limited to these examples.

<Example 1>
Each component was blended according to the following recipe, heated to 75° C. and stirred with a stirrer for 2 hours to prepare a curable resin composition.
Component (A): Curing resin A-i (n=1) 90.0 parts by mass Component (B): Oxetane compound B-iv 10.0 parts by mass Component (C): Photoacid generator "CPI-210S" (manufactured by San-Apro) 2.0 parts by mass

[Preparation of test piece]
A cured product was prepared from the prepared curable resin composition by the following method. First, a mold having a length of 80 mm, a width of 10 mm, and a thickness of 4 mm was sandwiched between two sheets of quartz glass, and a curable resin composition was poured into the mold. The poured curable resin composition was irradiated with UV rays of 5 mW/cm from ^both sides of the mold for 120 seconds each using an UV irradiation machine (manufactured by HOYA CANDEO OPTRONICS, trade name “LIGHT SOURCE EXECURE 3000”) to temporarily cure. did After that, UV rays were applied again from both sides for 600 seconds each for final curing to obtain a cured product (total energy: 7200 mJ/cm ² ). The resulting cured product was placed in a heating oven at 50°C for 1 hour and then placed in a heating oven at 100°C for 2 hours to obtain a test piece having a length of 80 mm, a width of 10 mm, and a thickness of 4 mm. rice field.

[evaluation]
(Charpy impact strength)
According to JIS K 7111 for the test piece, a notch of 2 mm depth and 45° is cut in the center of the test piece with a notch forming machine (manufactured by Toyo Seiki Seisakusho, trade name "Notching Tool A-4"). I put it in. Using an impact tester (manufactured by Toyo Seiki Seisakusho, trade name "IMPACT TESTER IT"), the test piece is destroyed with an energy of 2 J from the back of the notch. The energy required for breaking was calculated from the angle at which the hammer raised to 150° was swung up after breaking the test piece, and this was defined as Charpy impact strength and used as an index of toughness. Table 1 shows the results obtained.

(Load deflection temperature)
For test pieces, according to JIS K 7191-2, using a load deflection temperature tester (manufactured by Toyo Seiki Seisakusho, trade name "No. 533 HDT test device 3M-2"), bending stress 1.80 MPa, room temperature to 2 C. per minute. The temperature at which the amount of deflection of the test piece reached 0.34 mm was defined as the deflection temperature under load, and was used as an index of heat resistance. Table 1 shows the results obtained.

<Examples 2 to 7, Comparative Examples 1 to 6>
A curable composition was prepared in the same manner as in Example 1, and evaluated in the same manner as in Example 1, except that the types and contents of component (A) and component (B) were changed as shown in Table 1. Table 1 shows the results.

"EX-991L" (manufactured by Nagase ChemteX Corp.) used as component (A) in Comparative Example 3 is an epoxy resin having no aromatic ring in the molecular skeleton, and the molecular structure is shown in Ci below. expressed. In the formula, z represents repetition (z=14 to 15). "OXT-221" (manufactured by Toagosei Co., Ltd.) used as component (B) in Comparative Examples 5 and 6 is an oxetane compound having no aromatic ring in the molecular skeleton, and the molecular structure is C-ii below. is represented by

As shown in Table 1, all of Examples 1 to 7 according to the present invention have a Charpy impact strength of 4.0 KJ / m or more and a deflection temperature under load of 60 ° C. or more, and have both good toughness and heat resistance. We were able to. Moreover, there is a suitable range for the ratio of the curable resin (A) to the oxetane compound (B). surpassed.

Moreover, in Comparative Examples 3 to 6, both toughness and heat resistance could not be achieved, although the compounding ratio of the curable resin (A) and the oxetane compound (B) was within the suitable range. From this, it is understood that the molecular structure of the curable resin (A) has an aromatic ring and an alkylene group, and the molecular structure of the oxetane compound (B) has an aromatic ring, that is, weak intermolecular interaction (π-π stacking). Toughness and heat resistance could be improved by expressing it in the material.

Claims (14)

(A) a curable resin represented by the following general formula (1);

[X ₁ and X ₂ are independently a diphenylmethanediyl group, a diphenylpropanediyl group, a biphenylene group, or a diphenyletherdiyl group .
X ₃ is an alkylene group having 4 to 18 carbon atoms .
L ₁ and L ₂ are independently divalent linking groups represented by the following general formula (1-g) .

[p and q are independently integers of 0 to 5;
* represents a bond with X ₁ , X ₂ and X ₃ . ]
L ₃ and L ₄ are each independently a divalent linking group represented by general formula (1-d) below.

[g and h are independently integers of 0 to 5;
* represents a bond with Y ₁ , Y ₂ , X ₁ and X ₂ . ]
Y ₁ and Y ₂ are independently an epoxy group, a cycloalkene oxide group or an oxetanyl group.
n is the average value of repeating structural units and is a real number of 0.1 or more and 10 or less. ]
(B) an oxetane compound represented by the following general formula (2);

[X ₄ is a phenylene group, biphenylene group, naphthalenediyl group, anthracenediyl group, phenanthenediyl group, fluorenediyl group, diphenylmethanediyl group, diphenylethanediyl group, diphenylpropanediyl group, which may have a substituent; , a diphenyletherdiyl group, a diphenylsulfonediyl group, a triphenylethanediyl group or a tetraphenylmethanediyl group .
X ₅ and X ₆ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
L ₅ and L ₆ are each independently a divalent linking group represented by general formula (1-a) or (1-d) below .

[a, b, g, and h are independently integers of 0 to 5;
* represents X ₄ , a bond with an adjacent carbon atom. ]
s is the average value of repeating structural units and is a real number of 0.1 or more and 10 or less. ]
(C) a cationic polymerization initiator ;
and wherein the mass ratio of the curable resin (A) and the oxetane compound (B) is 5:5 to 9:1. 2. The curable resin composition according to claim 1, wherein said n is 1. 3. The curable resin composition according to claim 1, wherein said s is 1. The L _Five , L ₆ is independently a divalent linking group represented by the general formula (1-d), the curable resin composition according to any one of claims 1 to 3. 5. The curable resin composition according to any one of claims 1 to 4, wherein the mass ratio of the curable resin (A) and the oxetane compound (B) is 7:3 to 9:1. thing. Said X _Four is a phenylene group or a biphenylene group, which may have a substituent, the curable resin composition according to any one of claims 1 to 5. Claim 1, wherein the curable resin (A) is any one selected from the group consisting of general formulas (Ai) to (Avi) and (Ax) below. 7. The curable resin composition according to any one of items 1 to 6.

Said X _Five , X ₆ is an ethyl group, the curable resin composition according to any one of claims 1 to 7. 9. Any one of claims 1 to 8, wherein the oxetane compound (B) is any one selected from the group consisting of the following general formulas (B-ii) to (B-iv): The curable resin composition according to .

The curable resin composition according to any one of claims ₁ to 9 , wherein Y1 and Y2 _are epoxy groups. The curable resin composition according to any one of claims 1 to 10 , wherein the cationic polymerization initiator (C) is a photoacid generator. A method for producing a three-dimensional object, comprising the step of photocuring a curable resin composition layer by layer based on slice data to form a three-dimensional object,
A method for producing a three-dimensional object, wherein the curable resin composition is the curable resin composition according to any one of claims 1 to 11 . 13. The method of manufacturing a three-dimensional object according to claim 12 , further comprising a step of post-curing the object. 14. The method of manufacturing a three-dimensional molded object according to claim 13, wherein the molded object is heated in the post-curing step.