JP7207973B2 - 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.

An optical stereolithography method for obtaining a three-dimensional object by curing a liquid curable resin layer by layer with energy-active light such as ultraviolet rays and laminating the layers has been earnestly studied. Optical three-dimensional objects are being used not only for prototyping for shape confirmation (rapid prototyping), but also for creating molds (rapid tooling) and service parts (actual products) (rapid manufacturing). Charing). Along with this, the requirements for material properties (toughness, heat resistance, etc.) for three-dimensional objects are becoming more sophisticated, and these days, physical properties equivalent to engineering plastics are being sought.
Three-dimensional objects made of curable resin are required to have a certain degree of hardness (modulus of elasticity) and toughness, especially high fracture toughness. Patent Literature 1 discusses a system in which a polyhydric alcohol is added to a resin composition in order to improve the toughness of three-dimensional modeling.

Japanese Patent Application Laid-Open No. 2000-302964

However, since the elastic modulus and toughness are in a contradictory relationship, the elastic modulus of the composition of Patent Document 1 is low, and the elastic modulus is insufficient for rapid prototyping and rapid manufacturing.
Based on the circumstances as described above, an object of the present invention is to provide a resin composition capable of giving a cured product having both hardness (elastic modulus) and toughness.

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、下記一般式（１－ＶＩＩ）乃至（１－ＶＩＩＩ）のいずれかで表される。

［ｌは、４以上１８以下の整数である。
Ｒ ₁ 、Ｒ ₂ は、水素またはメチル基である。ｍは、炭素数が４以上１８以下となるように選択される整数である。
＊は、Ｌ ₁ 、Ｌ ₂ との結合手を表す。］
Ｌ₁、Ｌ₂、Ｌ₃、Ｌ₄は、独立に、下記一般式（１－ｄ）、（１－ｆ）、（１－ｇ）のいずれかで表される２価の連結基である。

［ｇ、ｈ、ｋ、ｏ、ｐ、ｑ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 、Ｘ ₃ との結合手を表す。］
Ｙ₁、Ｙ₂は、独立に、下記一般式（１－ｈ）で表されるエポキシ基または下記一般式（１－ｊ）で表されるシクロアルケンオキシド基である。

［Ｒ ₃ は、独立に、水素または炭素数１以上４以下のアルキル基である。
＊は、Ｌ ₃ 、Ｌ ₄ との結合手である。］
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）２個以上５個以下の水酸基を有する多価アルコール（ただし、ポリカーボネートジオールを除く。）と、
（Ｃ）硬化剤と、
（Ｄ）オキセタン化合物と、
を含有する硬化性樹脂組成物であって、
前記硬化性樹脂（Ａ）と前記オキセタン化合物（Ｄ）の合計１００質量部に対して、前記多価アルコール（Ｂ）を０．１質量部以上２０質量部以下で含有し、
前記硬化性樹脂（Ａ）と前記オキセタン化合物（Ｄ）の合計１００質量部に対して、前記オキセタン化合物（Ｄ）を５質量部以上９０質量部以下で含有することを特徴とする。

[X ₁ and X ₂ are independently a diphenylmethanediyl group, a diphenylpropanediyl group, a biphenylene group, or a diphenyletherdiyl group .
X ₃ is represented by any one of the following general formulas (1-VII) to (1-VIII) .

[l is an integer of 4 or more and 18 or less.
R ₁ and R ₂ are hydrogen or methyl groups. m is an integer selected such that the number of carbon atoms is 4 or more and 18 or less.
* represents a bond with L ₁ and L ₂ . ]
L ₁ , L ₂ , L ₃ and L ₄ are independently divalent linking groups represented by any of the following general formulas (1-d), (1-f) and (1-g) .

[g, h, k, o, p, and q are independently integers of 0 to 5;
* represents a bond with Y ₁ , Y ₂ , X ₁ , X ₂ and X ₃ . ]
Y ₁ and Y ₂ are independently an epoxy group represented by the following general formula (1-h) or a cycloalkene oxide group represented by the following general formula (1-j) .

[R ₃ is independently hydrogen or an alkyl group having 1 to 4 carbon atoms.
* is a bond with L ₃ and L ₄ . ]
n is the average value of repeating structural units and is a real number of 0.1 or more and 10 or less. ]
(B) a polyhydric alcohol having 2 or more and 5 or less hydroxyl groups (excluding polycarbonate diol) ;
(C) a curing agent;
(D) an oxetane compound;
A curable resin composition containing
0.1 parts by mass or more and 20 parts by mass or less of the polyhydric alcohol (B) with respect to a total of 100 parts by mass of the curable resin (A) and the oxetane compound (D) ,
It is characterized by containing 5 parts by mass or more and 90 parts by mass or less of the oxetane compound (D) with respect to a total of 100 parts by mass of the curable resin (A) and the oxetane compound (D) .

According to the present invention, it is possible to form a cured product excellent in both hardness (elastic modulus) and toughness, and to provide a curable resin composition suitable for three-dimensional modeling.

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. You may have 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. Moreover, when the number of carbon atoms is 19 or more, the hardness of the cured product is lowered, and as a result, the elastic modulus is impaired. 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 elastic modulus, and an alkylene group represented by the 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 elastic modulus 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 obtained by curing the composition do not decrease in water absorbency and 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 material, and an integer of 0 or more and 1 or less is more preferable from the viewpoint of maintaining the elastic modulus.

* 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 an increase in the 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 between toughness and elastic modulus 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 elastic modulus, 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).

(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 (2). 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 general formula (2) 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 (3). 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 (3) 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).

<Polyhydric alcohol (B) (component (B))>
The polyhydric alcohol (B) is useful for improving the toughness of the cured product. The polyhydric alcohol used as component (B) has 2 to 5 hydroxyl groups, preferably 2 to 4 hydroxyl groups, more preferably 2 hydroxyl groups per molecule. When an alcohol having one hydroxyl group in one molecule is used, poor curing occurs. On the other hand, when a polyhydric alcohol having 6 or more hydroxyl groups in one molecule is contained, the toughness of the resulting cured product tends to decrease.

Examples of dihydric alcohols include salicyl alcohol, catechol, resorcinol, hydroquinone, 1,4-benzenedimethanol, bisphenol A, bisphenol F, neopentyl glycol, ethylene glycol, propanediol, butanediol, pentanediol, and hexanediol. can be used. Examples of trihydric alcohols that can be used include glycerin, phloroglucinol, and trimethylolpropane. Examples of tetrahydric alcohols that can be used include erythritol, threitol, and pentaerythritol. Examples of pentahydric alcohols that can be used include xylitol, arabitol, fucitol, glucose, galactose and fructose. Polyhydric alcohol (B) is not limited to these. Moreover, polyhydric alcohol (B) can be used individually or in combination of 2 or more types.

The polyhydric alcohol (B) preferably has a molecular weight of 1,000 or less, more preferably 800 or less. If the molecular weight exceeds 1,000, there is a possibility that the crosslink density will be locally reduced and the elastic modulus will be reduced.

The content of the polyhydric alcohol (B) is 0.1 parts by mass or more with respect to 100 parts by mass of the component (A) (the total of the component (A) and the component (D) when the component (D) is included). It is 20 parts by mass or less, preferably 0.2 parts by mass or more and 15 parts by mass or less, and more preferably 0.5 parts by mass or more and 10 parts by mass or less. If the content of the polyhydric alcohol (B) is less than 0.1 parts by mass, the effects of the polyhydric alcohol (B) are not exhibited, and a cured product having a sufficient elastic modulus cannot be obtained. When the content of the polyhydric alcohol (B) exceeds 20 parts by mass, the polyhydric alcohol (B) polymerizes the component (A), and when the component (D) is contained, the component (A) and the component (D) are polymerized. sufficient toughness cannot be obtained.

(Function of polyhydric alcohol (B))
The mechanism for improving the toughness of the curable composition of the present embodiment will be described using an example where component (A) is an epoxy resin, component (C) is a cationic polymerization initiator, and component (D) is contained. do. When the cationic polymerization initiator absorbs active energy rays or thermal energy, it generates cations, which initiate cationic polymerization of the epoxy group of component (A) or the oxetanyl group of component (D). Epoxy groups and oxetanyl groups are cationic polymerized with each other or individually to increase the molecular weight, but the activated epoxy groups and oxetanyl groups are unstable, so the polymerization is likely to be terminated. Therefore, a low-molecular-weight polymer chain having an unreacted epoxy group or oxetanyl group at the end of the polymer is produced. The component (B) of the present embodiment, for example, reacts the low-molecular-weight polymer chains with hydroxyl groups to increase the molecular weight and improve the toughness, as shown in the following formula. In addition, it is presumed that the polyhydric alcohol incorporated into the polymer chain forms a hydrogen bond, thereby improving the toughness more efficiently.

<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.

(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 (R) 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.

(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.

(Addition amount of cationic polymerization initiator)
The amount of the cationic polymerization initiator added is 0.05 parts by mass or more and 20 parts by mass with respect to 100 parts by mass of component (A) (the total of component (A) and component (D) when component (D) is included). Part or less is preferable, and 0.1 to 5 parts by mass is more preferable. If the amount of the cationic polymerization initiator added is less than 0.05 parts by mass, the generated polymerization active species will be insufficient, resulting in a decrease in the polymerization conversion rate of the resin composition, which may result in insufficient strength of the cured product. . If the amount of the cationic polymerization initiator added exceeds 20 parts by mass, the number of initiation points for polymerization increases, and polymerization is not sufficiently repeated, which may result in a cured product with insufficient strength.

[Radical polymerization initiator]
In the present invention, a radical polymerization initiator may be contained particularly when the radically polymerizable compound (F) 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 (F) 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 (F) 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, relative to 100 parts by mass of the radically polymerizable compound (F). 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 (F). 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 part by mass or more per 100 parts by mass of component (A) (the total of component (A) and component (D) when component (D) is included). It is 75 parts by mass or less, more preferably 5 parts by mass or more and 30 parts by mass or less. If the amount of the thermal latent polymerization initiator is too small, the polymerization tends to be insufficient.

<Oxetane Compound (D) (Component (D))>
The curable resin composition of the present invention preferably contains an oxetane compound other than component (A).

The oxetane compound (D) 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. The number of oxetanyl groups in the oxetane compound (D) is not particularly limited. For example, monofunctional oxetane compounds having one oxetanyl group in the molecule, bifunctional oxetane compounds having two oxetanyl groups in the molecule, trifunctional oxetane compounds having three oxetanyl groups in the molecule, and oxetanyl groups in the molecule. Tetra- or higher-functional oxetane compounds having four or more may be mentioned, but not limited to these. Moreover, the oxetane compound (D) may be an oxetane compound having an aromatic ring or an ether bond in the molecule.

Specific examples of the oxetane compound (D) 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-methacryloxymethyl Monooxetane compounds such as oxetane, 3-ethyl-3-carboxyoxetane, 3-ethyl-3-phenoxymethyloxetane; bis[1-ethyl(3-oxetanyl)]methyl ether, 4,4'-bis[3-ethyl -(3-oxetanyl)methoxymethyl]biphenyl, 1,4-bis(3-ethyl-3-oxetanylmethoxy)methylbenzene, xylylene bisoxetane, bis[(ethyl(3-oxetanyl)]methyl carbonate, bis adipate [ethyl(3-oxetanyl)]ethyl, bis[ethyl(3-oxetanyl)]methyl terephthalate, bis[ethyl(3-oxetanyl)]methyl 1,4-cyclohexanecarboxylate, bis{4-[ethyl(3- dioxetane compounds such as oxetanyl)methoxycarbonylamino]phenyl}methane, α,ω-bis-{3-[1-ethyl(3-oxetanyl)methoxy]propyl (polydimethylsiloxane); and oligo(glycidyloxetane-co-phenyl glycidyl ether) and other multi-oxetane compounds, 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, 4,4'-bis[3-ethyl-(3-oxetanyl)methoxymethyl]biphenyl, 1 , 4-bis(3-ethyl-3-oxetanylmethoxy)methylbenzene, xylylenebisoxetane are preferred, 3-ethyl-3-[(2-ethylhexyloxy)methyl]oxetane, 3-ethyl-3-hydroxymethyloxetane , 3-ethyl-3-(4-hydroxybutyl)oxymethyloxetane, bis[1-ethyl(3-oxetanyl)]methyl ether, 4,4′-bis[3-ethyl-(3-oxetanyl)methoxymethyl] Biphenyl is more preferred.

As the oxetane compound (D), a commercially available product containing a cationic polymerizable monomer as a main component can be used. 101, OXT-211, OXT-212 (manufactured by Toagosei Co., Ltd.), ETERNACOLL (R) OXBP, OXTP (manufactured by Ube Industries, Ltd.) and the like.

Moreover, the oxetane compound (D) is preferably a compound represented by the following general formula (4).

In general formula (4), X ₈ is a residue of a dihydric alcohol, or a bond selected from the group consisting of —O—, —CO—, an ether bond, a carbonate bond, a urethane bond, and a urea bond. It represents a divalent linking group containing one or more and may contain an aromatic ring. A divalent compound represented by formula (4) is suitable for increasing the elastic modulus of the curable resin (A).

Examples of the compound represented by the general formula (4) include the compounds exemplified as the above dioxetane compounds. Commercially available products include Aronoxetane (R) OXT-121, OXT-221 (manufactured by Toagosei Co., Ltd.), and ETERNACOLL (R) OXBP (manufactured by Ube Industries, Ltd.). Among these, in particular, bis [1-ethyl (3-oxetanyl)] methyl ether has an ether bond and has flexibility to ensure toughness, and the molecular weight of X ₈ is small and the crosslink density is improved. It is suitable for obtaining the effects of the present invention in that it can be done. Further, 4,4'-bis[3-ethyl-(3-oxetanyl)methoxymethyl]biphenyl has an aromatic ring, the aromatic ring possessed by the component (A) of the present invention, and the cyclic ring possessed by the component (B) of the present invention. The interaction with the structure is strong, and it is suitable in terms of improving heat resistance.

Moreover, the oxetane compound (D) is preferably a compound represented by the following general formula (5).

The number of oxetanyl groups possessed by the compound represented by formula (5) is not particularly limited. Examples thereof include bifunctional oxetane compounds having two oxetanyl groups in the molecule, trifunctional oxetane compounds having three oxetanyl groups in the molecule, and tetrafunctional or higher oxetane compounds having four or more oxetanyl groups in the molecule. However, it is not limited to these. Among these, bifunctional oxetane compounds having two oxetanyl groups in the molecule are preferred.

In the above general formula (5), 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 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 0.2 or less from the viewpoint of the viscosity of the oxetane compound. 5 or more and 3 or less is more preferable.

As the compound represented by the general formula (5), ETERNACOLL (R) OXBP (manufactured by Ube Industries, Ltd.), ETERNACOLL (R) OXIPA (manufactured by Ube Industries, Ltd.), Aron Oxetane OXT-121 (manufactured by Toagosei Co., Ltd.), etc. are commercially available. products can be preferably used.

As a specific example of the compound represented by the general formula (5), a compound represented by the following structure is preferable from the viewpoint of achieving both toughness and elastic modulus.

The content of the oxetane compound (D) is preferably 5 parts by mass or more and 90 parts by mass or less, more preferably 10 parts by mass or more and 80 parts by mass or less with respect to a total of 100 parts by mass of the component (A) and the component (D). , more preferably 15 parts by mass or more and 70 parts by mass or less. When the content of the oxetane compound (D) is 5 parts by mass or more, a cured product having a sufficient elastic modulus can be obtained. If the content of the oxetane compound (D) exceeds 90 parts by mass, the crosslink density increases, and sufficient toughness may not be obtained.

<Cationically polymerizable compound (E) (component (E))>
The curable resin composition of the present invention may contain, for example, an epoxy resin or the like as a cationic polymerizable compound other than the component (A) and the component (D).

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.

In order to express the effect of the present invention, the content of the cationic polymerizable compound (E) is 100 parts by mass of the component (A) (the total of the component (A) and the component (D) when the component (D) is included). 0 parts by mass or more and 75 parts by mass or less is preferable. If the amount of the cationically polymerizable compound (E) is excessive, the effects of the present invention may be impaired.

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

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, phenylglycidyl (meth) acrylate, dimethylaminomethyl (meth) acrylate, phenyl cellosolve (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.

In order to express the effect of the present invention, the content of the radical polymerizable compound (F) is 100 parts by mass of the component (A) (the total of the components (A) and (D) when the component (D) is included). On the other hand, 0 mass part or more and 75 mass parts or less are preferable. If the amount of the radically polymerizable compound (F) is excessive, the effects of the present invention may be impaired.

<Curable resin composition>
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 epoxy resins, polyamides, polyamideimides, polyurethanes, polybutadiene, polychloroprene, polyethers, polyesters, styrene-butadiene block copolymers, petroleum resins, xylene resins, ketone resins, cellulose resins, fluorine-based oligomers, Polymers or oligomers such as silicone-based oligomers and polysulfide-based oligomers; polymerization inhibitors such as phenothiazine and 2,6-di-t-butyl-4-methylphenol; polymerization initiation aids; leveling agents; wettability improvers; plasticizers; UV absorbers; silane coupling agents; inorganic fillers; pigments;

The composition of the present invention is prepared by adding appropriate amounts of essential components (A), (B) and (C), and optionally component (D) and other optional components to a stirring vessel, and heating at 30°C or higher and 120°C. °C or less, preferably 50 °C or more and 100 °C or less. 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) (when component (D) is included, the total of component (A), component (B), and component (D)) is With respect to 100 parts by mass of the curable resin composition, it is preferably 1 part by mass or more and 100 parts by mass or less, more preferably 25 parts by mass or more and 100 parts by mass or less, still more preferably 75 parts by mass or more and 100 parts by mass or less. , the effect of the present invention can be sufficiently obtained.

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), a polyhydric alcohol (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.

In the obtained cured product of the present invention, the curable resin (A) has a strong intermolecular interaction because it has an aromatic ring. It has the effect of accelerating the curing of A). In addition, since X ₃ of the curable resin (A) is a flexible skeleton, the skeleton can be cured in a bent state, and rigid X ₁ and X ₂ are relatively free in the cured product. placement can be taken. Therefore, after curing, the rigid structures of the curable resin (A) interact very effectively. Taking the case where the component (A) is an epoxy resin as an example, there is a problem that the polymer chain is difficult to extend because the protonated epoxy group is unstable in the cationic polymerization system. In the present invention, it is believed that adding an appropriate amount of the polyhydric alcohol (B) to the resin composition reacts unreacted epoxy groups, thereby causing extension of the polymer chain. In addition, the toughness is improved by effectively generating interaction through hydrogen bonding with the oxygen atoms of the curable resin (A) or the oxetane compound (D). In addition, it is considered that the extension of the polymer chains and the effect of physical cross-linking due to hydrogen bonding prevented free movement of the polymer chains, resulting in an improvement in the elastic modulus. From these facts, it is considered that although the elastic modulus and the toughness are usually contradictory physical properties, it is possible to exhibit a characteristic hardening that makes the two contradictory physical properties compatible.

<Manufacturing method of three-dimensional object>
The curable resin composition according to the present embodiment can be suitably used in a method for producing a three-dimensional object by optical stereolithography (stereolithography). A method for manufacturing a three-dimensional object using the curable resin composition according to this embodiment will be described below.

A conventionally known method can be used as the stereolithography method. That is, in the method for producing a three-dimensional object of the present embodiment, the curable resin composition of the present embodiment is selectively irradiated with an active energy ray such as light, and the curable resin composition is photocured layer by layer. It is a method of manufacturing a three-dimensional object by repeating the process of curing such as.

In the step of curing the curable resin composition layer by layer, the curable resin composition is selectively irradiated with active energy rays based on the slice data of the three-dimensional object to be created. The active energy ray with which the curable resin composition is irradiated is not particularly limited as long as it can cure the curable resin composition according to the present embodiment. Specific examples of active energy rays include electromagnetic waves such as ultraviolet rays, visible rays, infrared rays, X-rays, gamma rays and laser beams, and particle beams such as alpha rays, beta rays and electron beams. Among these, ultraviolet light is most preferable from the viewpoint of the absorption wavelength of the curing agent (C) used and the cost of introducing equipment. Although the exposure amount is not particularly limited, it is preferably 0.001 J/cm ² or more and 10 J/cm ² or less. If it is less than 0.001 J/cm ² , the curable resin composition may not be sufficiently cured, and if it exceeds 10 J/cm ² , the irradiation time will be long and productivity will drop.

The method of irradiating the curable resin composition with active energy rays is not particularly limited. A first method includes a method of using spot-focused light such as laser light and two-dimensionally scanning the curable resin composition with this light. At this time, the two-dimensional scanning may be a stippling method or a line drawing method. As a second method, there is a surface exposure method in which a projector or the like is used to irradiate the shape of the cross-sectional data with light. In this case, the active energy ray may be planarly irradiated through a planar drawing mask formed by arranging a plurality of minute light shutters such as liquid crystal shutters or digital micromirror shutters.

In this step, after obtaining a modeled article by stereolithography, the surface of the obtained modeled article may be washed with a cleaning agent such as an organic solvent. In addition, post-curing may be performed to cure unreacted residual components that may remain on the surface or inside of the shaped article by subjecting the obtained shaped article to light irradiation or heat treatment.

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

<Example 1>
According to the following recipe, each component was placed in a light-shielding bottle and stirred until uniform using a stirring and deaerator to prepare a curable composition.
Component (A): Curing resin Ai (n = 1) (manufactured by DIC "EXA4816" (purity 99%)) 70 parts by mass Component (B): 1,4-benzenedimethanol 6 parts by mass Component (C ): Photoacid generator "CPI-210S" (manufactured by San-Apro Co., Ltd.) 2 parts by mass Component (D): Oxetane compound represented by the following formula (manufactured by Toagosei Co., Ltd. "OXT-221") 30 parts by mass

[Preparation of cured product and evaluation of mechanical properties]
・Preparation of film test piece (for elastic modulus evaluation)
Using the prepared curable composition, a cured product was produced by the following method. First, a 300 μm spacer was sandwiched between two pieces of quartz glass, and the curable composition was poured into this 300 μm wide gap. The poured curable composition was irradiated with ultraviolet rays of 5 mW/cm ² for 300 seconds (total energy 1500 mJ/cm ² ) using an ultraviolet irradiator (manufactured by HOYA CANDEO OPTRONICS, trade name “LIGHT SOURCE EXECURE 3000”) to obtain a photocured product. got 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 cured product.

・Creation of columnar test piece (for toughness evaluation)
Using the prepared curable composition, a cured product was produced 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 pieces of quartz glass, and a curable resin was poured into the mold. The poured curable composition was subjected to temporary curing by irradiating ultraviolet rays of 5 mW/cm ² from both sides of the mold for 120 seconds each using the ultraviolet irradiator used to prepare the film-shaped test piece. 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 cured product.

・Measurement and evaluation of elastic modulus (test method for tensile properties)
The resulting photo-thermosetting material having a thickness of about 300 μm was punched into a No. 8 dumbbell shape to prepare a test piece. This test piece was measured according to JIS K 7127 using a tensile tester (trade name "Strograph EII", manufactured by Toyo Seiki Seisakusho) at a test temperature of 23 ° C. and a tensile speed of 10 mm / min. was measured as an index of stiffness. Table 1 shows the results.

・Measurement and evaluation of toughness (how to obtain Charpy impact properties)
The resulting test piece having a length of 80 mm, a width of 10 mm, and a thickness of 4 mm was cut in the center of the test piece with a notch forming machine (manufactured by Toyo Seiki Seisakusho, trade name "Notching Tool A-4") according to JIS K 7111. A notch with a depth of 2 mm and 45° was made in the . After that, 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 of the test piece. 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 used as an index of toughness. Table 1 shows the results.

<Examples 2-5, Comparative Examples 1-2>
A curable composition was prepared and evaluated in the same manner as in Example 1, except that the content of each component and the number of hydroxyl groups in component (B) were changed as shown in Table 1. Table 1 shows the results. The component (B) used in each example and comparative example is as follows.
Example 2: 1,6-Hexanediol Example 3: Trimethylolpropane Example 4: Erythritol Example 5: Erythritol Comparative Example 2: Mannitol

Compared with Comparative Example 1 in which no polyhydric alcohol was added, Examples 1 to 5 were confirmed to have improved toughness values and elastic moduli. In addition, when a polyhydric alcohol having two hydroxyl groups was used (Examples 1 and 2), the system to which the oxetane compound (D) was added had the highest toughness value and elastic modulus. In Example 5, although the oxetane compound (D) was not added, a cured product having sufficient toughness and elastic modulus could be produced. When the number of hydroxyl groups in the polyhydric alcohol was 6 (Comparative Example 2), the toughness value was reduced to about half that when no polyhydric alcohol was added (Comparative Example 1).

Claims (9)

(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 represented by any one of the following general formulas (1-VII) to (1-VIII) .

[l is an integer of 4 or more and 18 or less.
R ₁ and R ₂ are hydrogen or methyl groups. m is an integer selected such that the number of carbon atoms is 4 or more and 18 or less.
* represents a bond with L ₁ and L ₂ . ]
L ₁ , L ₂ , L ₃ and L ₄ are independently divalent linking groups represented by any of the following general formulas (1-d), (1-f) and (1-g) .

[g, h, k, o, p, and q are independently integers of 0 to 5;
* represents a bond with Y ₁ , Y ₂ , X ₁ , X ₂ and X ₃ . ]
Y ₁ and Y ₂ are independently an epoxy group represented by the following general formula (1-h) or a cycloalkene oxide group represented by the following general formula (1-j) .

[R ₃ is independently hydrogen or an alkyl group having 1 to 4 carbon atoms.
* is a bond with L ₃ and L ₄ . ]
n is the average value of repeating structural units and is a real number of 0.1 or more and 10 or less. ]
(B) a polyhydric alcohol having 2 or more and 5 or less hydroxyl groups (excluding polycarbonate diol) ;
(C) a curing agent;
(D) an oxetane compound;
A curable resin composition containing
0.1 parts by mass or more and 20 parts by mass or less of the polyhydric alcohol (B) with respect to a total of 100 parts by mass of the curable resin (A) and the oxetane compound (D) ,
A curable resin characterized by containing 5 parts by mass or more and 90 parts by mass or less of the oxetane compound (D) with respect to a total of 100 parts by mass of the curable resin (A) and the oxetane compound (D). Composition. The polyhydric alcohol (B) includes salicyl alcohol, catechol, resorcinol, hydroquinone, 1,4-benzenedimethanol, bisphenol A, bisphenol F, neopentyl glycol, ethylene glycol, propanediol, butanediol, pentanediol, hexanediol. , glycerin, phloroglucinol, trimethylolpropane, erythritol, threitol, pentaerythritol, xylitol, arabitol, fucitol, glucose, galactose and fructose. curable resin composition. _3. The curable resin composition according to claim ₁ , wherein said Y1 and said Y2 are epoxy groups. 4. The curable resin composition according to any one of claims 1 to 3 , wherein the polyhydric alcohol (B) has a molecular weight of 1,000 or less. 5. The curable resin composition according to any one of claims 1 to 4, wherein the oxetane compound (D) is represented by the following general formula (4).

[X ₈ is a residue of a divalent alcohol, or a divalent containing one or more bonds selected from the group consisting of -O-, -C-O-, an ether bond, a carbonate bond, a urethane bond, and a urea bond and may contain an aromatic ring. ] The curable resin composition according to any one of claims 1 to 5 , wherein the curing agent (C) is a photoacid generator. A cured product obtained by curing the curable resin composition according to any one of claims 1 to 6 . 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 6 . 9. The method of manufacturing a three-dimensional object according to claim 8 , further comprising the step of heat-treating the three-dimensional object to obtain a three-dimensional object.