JP4843955B2 - Photobase generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photobase generating agent showing a high activity and to provide a hardenable composition containing episulfide which is hardened easily by UV irradiation and the item hardened by UV irradiation. <P>SOLUTION: This photobase generating agent is shown in formula (1). Wherein Ar is a phenyl, biphenyl, napthyl or 4-(phenyl thio) phenyl group which is not substituted or mono- or poly-substituted with a 1-18C alkyl, 3-18C alkenyl, 3-18C alkynyl, or 1-18C haloalkyl group, or NO<SB>2</SB>, OH, CN, OR<SB>1</SB>, SR<SB>2</SB>, C(O)R<SB>3</SB>, C(O)OR<SB>4</SB>or a halogen (wherein R<SB>1</SB>, R<SB>2</SB>, R<SB>3</SB>and R<SB>4</SB>are each hydrogen or a 1-18C alkyl); R is hydrogen or a 1-18C alkyl; -A<SP>+</SP>is an ammonium ion; X<SP>-</SP>is a borate anion, an N,N-dimethyldithiocarbamate anion, an N,N-dimethylcarbamate anion, a thiocyanate anion or a cyanate anion. <P>COPYRIGHT: (C)2005,JPO&amp;NCIPI

Description

  The present invention relates to a photobase generator useful for producing optical materials such as an optical element adhesive, an optical element coating agent, a resist material, a prism, an optical fiber, an information recording substrate, a filter, and a plastic lens, and the photobase generation. The present invention relates to a curable composition containing an agent.

  In recent years, plastic materials are widely used in various optical materials because they are light and tough and easy to dye. One of the performances required for many optical materials is a high refractive index. As for optical materials having a high refractive index, a large number of episulfide compounds that enable optical materials having a refractive index of 1.7 or more have been found (see Patent Documents 1, 2, and 3). Most of the curing methods for materials using these compounds are thermosetting, so there are significant restrictions on applications, and materials that can be photocured have been strongly desired.

The photocuring of episulfide compounds is described in Patent Documents 4, 5, 6, 7, and 8. In these documents, radical generators, acid generators, base generators, etc. are disclosed as initiators, but base catalysts are the most active for the polymerization of episulfide compounds. Is considered the most desirable. However, the history of research on photobase generators is short, and no base generator exhibiting activity that can withstand practical use has been found so far. The research on the photobase generator is described in Non-Patent Documents 1 and 2.
The main problems of the photobase generators developed so far are the following two.
(1) The episulfide compound absorbs light up to around 300 nm, but the light absorption region of the photobase generator almost overlaps with this, and the generation efficiency of the base by photolysis is low.
(2) The basicity of the base generated by photolysis is weak and the episulfide compound is slow to cure.

JP-A-9-71580 Japanese Patent Laid-Open No. 9-110979 Japanese Patent Laid-Open No. 9-255781 WO 01/57113 Japanese Patent Laid-Open No. 2002-047346 JP-A-2002-105110 US2003 / 0022956 Japanese Patent Application Laid-Open No. 2003-026806 Chemical Industry, 50, p592-600 (1999) J.Polym.Sci.PartA, vol39, p1329-1341 (2001)

  An object of the present invention is to provide a photobase generator exhibiting high activity, and further to provide a curable composition containing episulfide that is easily cured by ultraviolet irradiation, and a cured product obtained by ultraviolet irradiation.

  As a result of studies conducted by the present inventors to solve the above problems, the compound represented by the following general formula (1) absorbs ultraviolet rays having a relatively long wavelength (300 nm or more, preferably 300 to 330 nm). And a composition containing an episulfide compound having at least two thiirane rings in the molecule and a photobase generator represented by the general formula (1) is irradiated with ultraviolet rays. It was found that the desired cured product can be obtained.

ここで、Arはフェニル、ビフェニル、ナフチル，４−（フェニルチオ）フェニル基であって、これらの基は非置換であるか、またはC1〜C18アルキル、C3〜C18アルケニル、C3〜C18アルキニル、C1〜C18ハロアルキル、NO2、OH、CN、OR_１、SR_２、C(O)R_３、C(O)OR_４もしくはハロゲンによりモノ置換またはポリ置換されており（式中R_１、R_２、R_３、R_４は水素またはC1〜C18アルキルである）、Ｒは水素又はＣ１〜Ｃ１８アルキル基であり、−Ａ^＋は下記構造式から選ばれるアンモニウムイオンであり（式中、Lは１または０、R_５はC1〜C5アルキルである）、

Here, Ar is a phenyl, biphenyl, naphthyl, 4- (phenylthio) phenyl group, and these groups are unsubstituted or C1-C18 alkyl, C3-C18 alkenyl, C3-C18 alkynyl, C1- C18 haloalkyl, NO2, OH, CN, oR 1, SR 2, C (O) R 3, C (O) and mono- or poly-substituted by oR ₄ or halogen (wherein R _1, R _2, R ₃ , R ₄ is hydrogen or C1~C18 alkyl), R is hydrogen or C1~C18 alkyl group, -A ⁺ is an ammonium ion selected from the following structural formulas (wherein, L is 1 or 0, R ₅ is C1-C5 alkyl)

Ｘ⁻はボレートアニオン、N,N-ジメチルジチオカルバメートアニオン、N,N-ジメチルカルバメートアニオン、チオシアネートアニオンまたはシアネートアニ

X ^- is a borate anion, N, N-dimethyldithiocarbamate anion, N, N-dimethylcarbamate anion, thiocyanate anion or Shianetoani

  ADVANTAGE OF THE INVENTION According to this invention, while being able to provide the base generator which shows high activity, the curable composition containing the episulfide which is easily effective by ultraviolet irradiation and the hardened | cured material obtained by ultraviolet irradiation can be provided.

The photobase generator of the present invention has the following general formula (1):

で表され、比較的長波長の紫外線（３００nm以上）を吸収することにより分解し、下記式で表される強塩基Ａ：

Which is decomposed by absorbing a relatively long wavelength ultraviolet ray (300 nm or more), and a strong base A represented by the following formula:

すなわち、１，８−ジアザビシクロ[５，４，０]−７−ウンデセン誘導体、１，５−ジアザビシクロ[４，３，０]−５−ノネン、トリエチレンジアミン、ヘキサメチレンテトラミンあるいはトリス（ジエチルアミノ）ホスフィンを発生するため、エピスルフィド化合物の重合に対する活性が極めて高い。

That is, 1,8-diazabicyclo [5,4,0] -7-undecene derivative, 1,5-diazabicyclo [4,3,0] -5-nonene, triethylenediamine, hexamethylenetetramine or tris (diethylamino) phosphine Therefore, the activity of the episulfide compound for polymerization is extremely high.

In the general formula (1), Ar is a phenyl, biphenyl, naphthyl, 4- (phenylthio) phenyl group, and these groups are unsubstituted or C1-C18 alkyl, C3-C18 alkenyl, C3-C18. alkynyl, C1 - C18 haloalkyl, NO2, OH, CN, oR 1, SR 2, C (O) R 3, C (O) has been mono- or poly-substituted by oR ₄ or halogen (wherein R _1, R ₂ , R ₃ and R ₄ are hydrogen or C 1 -C 18 alkyl), Ar is preferably substituted or unsubstituted phenyl, most preferably unsubstituted phenyl.
R is hydrogen or C1-C18 alkyl, preferably hydrogen or C1-C3 alkyl, most preferably hydrogen.

-A ⁺ is an ammonium ion selected from the following structural formula,

（式中、Ｌは１または０、R_５はC1〜C5アルキルである）
下記構造式であることが好ましい。

(Wherein L is 1 or 0 and R ₅ is C1-C5 alkyl)
The following structural formula is preferred.

（式中、Lは１または０、R_５はC1〜C5アルキルであり、特にＬが０であることが好ましい。）

(In the formula, L is 1 or 0, R ₅ is C1-C5 alkyl, and L is particularly preferably 0.)

X ⁻ represents a counter anion of A ⁺ and is a borate anion, N, N-dimethyldithiocarbamate anion, N, N-dimethylcarbamate anion, thiocyanate anion or cyanate anion, and is preferably a borate anion. Specific examples of the borate anion include the following compounds. Tetraphenylborate, methyltriphenylborate, ethyltriphenylborate, propyltriphenylborate, butyltriphenylborate, pentyltriphenylborate, hexyltributylborate.

  The photobase generator of the present invention can be easily synthesized by a known method (J. Polym. Sci. Part A, vol39, p1329-1341 (2001), etc.). An example of the synthesis route is shown in the figure below.

式中、Ａｒ、Ｒ、-Ａ⁺、Ａ、Ｘ^-は前記と同様であり、Ｍはアルカリ金属を表す。

In the formula, Ar, R, -A ⁺ , A, and X ^- are the same as described above, and M represents an alkali metal.

  The curable resin composition of the present invention contains a photobase generator of formula (1) and an episulfide compound. The episulfide compound used in the present invention may be any compound having at least two or more thiirane rings in the molecule. However, since an optical material having a higher refractive index can be obtained, the episulfide represented by the general formula (2) Compounds are preferred.

式（２）において、Ｒ^６、Ｒ^７はそれぞれ独立に、水素原子又はＣ１〜Ｃ１０の一価の炭化水素基、好ましくは水素原子、又はＣ１〜Ｃ３の１価の炭化水素基であり、最も好ましくは水素原子であり、Ｒ^８、Ｒ^９はそれぞれ独立にＣ１〜Ｃ１０の２価の炭化水素基、好ましくはメチレン、エチレン、プロピレンである。ｎは０〜４の整数、ｍは０〜６の整数である。

In the formula (2), R ⁶ and R ⁷ are each independently a hydrogen atom or a C1-C10 monovalent hydrocarbon group, preferably a hydrogen atom or a C1-C3 monovalent hydrocarbon group, Preferably, it is a hydrogen atom, and R ⁸ and R ⁹ are each independently a C1-C10 divalent hydrocarbon group, preferably methylene, ethylene, or propylene. n is an integer of 0 to 4, and m is an integer of 0 to 6.

Specific examples of the episulfide compound of the formula (2) include bis (2,3-epithiopropyl) sulfide, bis (2,3-epithiopropylthio) ethane, and bis (2,3-epithiopropylthio) propane. Bis (2,3-epithiopropylthio) butane, bis (5,6-epithio-3-thiohexane) sulfide, bis (2,3-epithiopropyl) disulfide, bis (3,4-epithiobutyl) disulfide, Bis (4,5-epithiopentyl) disulfide and bis (5,6-epithiohexyl) disulfide may be mentioned, but bis (2,3-epithiopropyl) sulfide (n = 0, R ⁶ = R ⁷ = hydrogen ^{atom, R} 8 = R ⁹ = methylene), bis (2,3-epithiopropyl) disulfide ^{(n = 1, m = 0} , R 6 = R 7 = hydrogen, ⁸ = ^{R 9} = methylene), are particularly preferred.

The usage-amount of a photobase generator is 0.001-50 weight part with respect to 100 weight part of episulfide compounds, Preferably it is 0.005-30 weight part, More preferably, it is 0.01-20 weight part. It is.

  A sensitizer can be added to the episulfide compound of the present invention. By adding a sensitizer, curing is possible by irradiation with low energy ultraviolet rays. Specific examples include benzophenone, acetophenone, thioxanthone, anthracene, perylene, and phenothiazine. The sensitizer is not limited to these listed compounds as long as it is sensitive to ultraviolet rays and accelerates the polymerization curing action. When the sensitizer is used, the addition amount is 0.001 to 50 parts by weight, preferably 0.005 to 30 parts by weight, more preferably 0.01 to 100 parts by weight with respect to 100 parts by weight of the episulfide compound. 20 parts by weight.

  Some photobase generators represented by general formula (1) have low solubility in episulfide compounds. In this case, a solvent capable of dissolving the photobase generator can be used in combination. Although there is no restriction | limiting in particular in the solvent to use together, The thing which does not inhibit a polymerization reaction with the high solubility of a photobase generator is preferable. Specific examples include lactones such as γ-butyrolactone, ethers such as tetrahydrofuran and diethyl ether, amides such as N, N-dimethylformamide, aromatic hydrocarbons such as toluene, and fats such as hexane. Examples include aromatic hydrocarbons, ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate, alcohols such as isopropyl alcohol, and alkyl halides such as dichloromethane. When the solvent is used, the amount used is preferably 0.1 to 100 parts by weight, more preferably 1 to 30 parts by weight, and most preferably 1 to 20 parts by weight with respect to 100 parts by weight of the episulfide compound.

  In addition, for the purpose of improving various properties such as weather resistance, oxidation resistance, strength, surface hardness, adhesion, refractive index, dyeability, etc., mercaptans, epoxy compounds, iso (thio) cyanates, phenols, amines Inorganic compounds having a sulfur atom, inorganic compounds having a selenium atom, and the like can be added. In this case, a known polymerization curing catalyst can be added separately as necessary.

Further, powdery, particulate, and fibrous fillers can be added as long as light transmission and reaction are not hindered. Specific examples include inorganic compounds such as silica, alumina, titania, zirconia, and calcium carbonate, and metal particles such as copper, silver, and gold.
The curable composition of the present invention is produced by physically mixing a photobase generator, an episulfide compound, and optional components by known means and conditions.

The curable composition of the present invention is cured, for example, by irradiating with ultraviolet rays under conditions of an illuminance of 1 to 100 mW / cm ² , a temperature of 0 to 100 ° C., about 1 second to about 1 day, preferably about 10 seconds to 1 hour. The
The ultraviolet ray source to be used is not particularly limited as long as it is an apparatus that generates ultraviolet rays. Specifically, a high pressure mercury lamp, an ultra high pressure mercury lamp, a metal halide lamp, and a high power metal halide lamp can be mentioned.
Since the photobase generator of formula (1) is included, the curing of the curable composition of the present invention proceeds very quickly. For example, as described in Example 5 below, the curing rate is higher than that of conventional light. More than twice as much as when a base generator is used.

  The curing reaction due to ultraviolet irradiation is susceptible to inhibition by oxygen. Therefore, the atmosphere at the time of ultraviolet irradiation is preferably an oxygen concentration of 3% or less, more preferably 0.5% or less, and most preferably 0.3% or less.

Curing can be further accelerated | stimulated by performing a heat processing after irradiating an ultraviolet-ray to a curable composition. The heating temperature and time can be appropriately selected depending on the degree of curing after UV irradiation, but the heating temperature is preferably room temperature to 200 ° C., and the heating time is preferably 1 minute to 3 days.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

Example 1
Synthesis of 1- (4′-phenylthio) phenacyl- (1-azonia-4-azabicyclo [2.2.2] octane) tetraphenylborate (I)

（１）１−(４’−フェニルチオ)フェナシル−(１−アゾニア−４−アザビシクロ[２．２．２]オクタン)ブロマイドの合成
１００ｍｌナス型フラスコに２−ブロモ−４’−フェニルチオアセトフェノン１．４１ｇ(０．００４６ｍｏｌ)、アセトン２０ｍｌを入れ、その後攪拌を行い均一溶液とした。１，４−ジアザビシクロ[２．２．２]オクタン０．５２ｇ(０．００４６ｍｏｌ)を溶かしたアセトン溶液２０ｍｌを室温でフラスコに入れ、引き続き１時間攪拌を続けた。その後、析出した固体をろ別し、１０ｍｌのアセトンで２回洗浄後乾燥させ、白色固体を１．６０ｇ(０．００３８ｍｏｌ、収率８３％)得た。^１Ｈ−ＮＭＲによる分析の結果、白色固体は目的物である１−(４’−フェニルチオ)フェナシル−(１−アゾニア−４−アザビシクロ[２．２．２]オクタン)ブロマイドであることを確認した。

(1) Synthesis of 1- (4′-phenylthio) phenacyl- (1-azonia-4-azabicyclo [2.2.2] octane) bromide 2-bromo-4′-phenylthioacetophenone in a 100 ml eggplant type flask. 41 g (0.0046 mol) and 20 ml of acetone were added, followed by stirring to obtain a uniform solution. 20 ml of an acetone solution in which 0.52 g (0.0046 mol) of 1,4-diazabicyclo [2.2.2] octane was dissolved was placed in a flask at room temperature, and stirring was continued for 1 hour. Thereafter, the precipitated solid was separated by filtration, washed twice with 10 ml of acetone and then dried to obtain 1.60 g (0.0038 mol, yield 83%) of a white solid. As a result of analysis by ¹ H-NMR, it was confirmed that the white solid was 1- (4′-phenylthio) phenacyl- (1-azonia-4-azabicyclo [2.2.2] octane) bromide which is the target product. .

(2) Synthesis of 1- (4′-phenylthio) phenacyl- (1-azonia-4-azabicyclo [2.2.2] octane) tetraphenylborate In a 100 ml eggplant type flask, the obtained 1- (4′- Phenylthio) phenacyl- (1-azonia-4-azabicyclo [2.2.2] octane) bromide (1.00 g, 0.0024 mol) and ethanol (20 ml) were added and stirred. To this, 20 ml of an ethanol solution in which 0.86 g (0.0025 mol) of sodium tetraphenylborate was dissolved was added at room temperature, followed by stirring for 1 hour. Thereafter, the solid in the flask was filtered and dried to obtain 1.34 g (0.0020 mol, yield 85%) of a white solid. As a result of analysis by ¹ H-NMR, it was confirmed that the white solid was 1- (4′-phenylthio) phenacyl- (1-azonia-4-azabicyclo [2.2.2] octane) tetraphenylborate, which is the target product. confirmed.

¹ H-NMR (δ, ppm)
7.77-6.84 (m, 29H, ArH) , 4.61 (s, 2H, COCH 2),
3.46 (m, 6H, CH ₂ ), 3.11 (m, 6H, CH ₂ )

Example 2
Synthesis of 1- (4′-phenylthio) phenacyl- (5-azonia-1-azabicyclo [4.3.0] -5-nonene) tetraphenylborate (II)

１００ｍｌナス型フラスコに、２−ブロモ−４’−フェニルチオアセトフェノン１．７４ｇ（０．００５７ｍｏｌ）、ジエチルエーテル30ｍｌを入れ、その後攪拌を行い均一溶液とした。１、５−ジアザビシクロ［４．３．０］−５−ノネン０．５０ｇ（０．００４０ｍｏｌ）を溶かしたジエチルエーテル３０ｍｌを氷浴下でフラスコに入れ、引き続き３０分間攪拌を続けた。その後、析出した固体をろ別し、３０ｍｌのジエチルエーテルで２回洗浄した。
得られた橙色固体を１００ｍｌナス型フラスコに移し、エタノール３０ｍｌを入れ攪拌を行った。これにナトリウムテトラフェニルボレート０．９７ｇ（０．００２８ｍｏｌ）を溶かしたエタノール溶液３０ｍｌを氷浴下で加え、引き続き３０分間攪拌を行った。その後、フラスコ内の固体をろ別し乾燥させ、白色固体を１．６７ｇ（０．００２５ｍｏｌ、収率８８％）を得た。^１Ｈ−NMRによる分析の結果、白色固体は目的物であることを確認した。

To a 100 ml eggplant-shaped flask, 1.74 g (0.0057 mol) of 2-bromo-4′-phenylthioacetophenone and 30 ml of diethyl ether were added, followed by stirring to obtain a homogeneous solution. 30 ml of diethyl ether in which 0.50 g (0.0040 mol) of 1,5-diazabicyclo [4.3.0] -5-nonene was dissolved was placed in a flask under an ice bath, and stirring was continued for 30 minutes. Thereafter, the precipitated solid was filtered off and washed twice with 30 ml of diethyl ether.
The obtained orange solid was transferred to a 100 ml eggplant type flask, and 30 ml of ethanol was added and stirred. To this, 30 ml of an ethanol solution in which 0.97 g (0.0028 mol) of sodium tetraphenylborate was dissolved was added in an ice bath, followed by stirring for 30 minutes. Thereafter, the solid in the flask was filtered and dried to obtain 1.67 g (0.0025 mol, yield 88%) of a white solid. As a result of analysis by ¹ H-NMR, it was confirmed that the white solid was the target product.

¹ H-NMR (δ, ppm), CD ₃ CN
_{7.82-6.84 (m, 29H, ArH)} , 4.84 (s, 2H, COCH 2), 3.70-3.68 (m, 2H, CH 2), 3.38 (t, 2H _{, CH 2), 3.32 (t} , 2H, CH 2), 2.71 (t, 2H, CH 2), 2.15-2.13 (m, 4H, CH 2)

Example 3
Synthesis of 1- (4′-phenylthio) phenacyl- (8-azonia-1-azabicyclo [5.4.0] -7-undecene) tetraphenylborate (III)

実施例２で用いた１、５−ジアザビシクロ［４．３．０］−５−ノネンを１、８−ジアザビシクロ［５．４．０］−７−ウンデセンに替えた以外は実施例２と同様の操作を行い、目的化合物を得た。

The same as Example 2 except that 1,5-diazabicyclo [4.3.0] -5-nonene used in Example 2 was replaced with 1,8-diazabicyclo [5.4.0] -7-undecene. The target compound was obtained by operating.

¹ H-NMR (δ, ppm), CD ₃ CN
_{7.83-6.83 (m, 29H, ArH)} , 5.02 (s, 2H, COCH 2), 3.62 (t, 2H, CH 2), 3.51 (t, 2H, CH 2) _{, 3.34 (t, 2H, CH} 2), 2.55 (m, 2H, CH 2), 2.16-2.12 (m, 2H, CH 2), 1.71 (m, 4H, CH _{2), 1.58 (m, 2H} , CH 2)

Reference experiment 1
Synthesis of 1-phenacyl- (1-azonia-4-azabicyclo [2.2.2] octane) tetraphenylborate (IV)

実施例１（１）で用いた２−ブロモ−４’−フェニルチオアセトフェノンを２-ブロモアセトフェノンに替えた以外は実施例１と同様の操作を行い、目的化合物を得た。化合物の確認は^１Ｈ−ＮＭＲにより行った。

The target compound was obtained in the same manner as in Example 1 except that 2-bromo-4′-phenylthioacetophenone used in Example 1 (1) was replaced with 2-bromoacetophenone. The compound was confirmed by ¹ H-NMR.

Reference experiment 2
Synthesis of 1-naphthoylmethyl- (1-azonia-4-azabicyclo [2.2.2] octane) tetraphenylborate (V)

実施例１（１）で用いた２−ブロモ−４’−フェニルチオアセトフェノンを２−ブロモアセチルナフタレンに替えた以外は実施例１と同様の操作を行い、目的化合物を得た。化合物の確認は^１Ｈ−ＮＭＲにより行った。

The target compound was obtained in the same manner as in Example 1 except that 2-bromo-4′-phenylthioacetophenone used in Example 1 (1) was replaced with 2-bromoacetylnaphthalene. The compound was confirmed by ¹ H-NMR.

Example 4
Measurement of molar light absorption coefficient of photobase generator The molar light absorption coefficient ε (254 nm, 313 nm) of the photobase generator synthesized in Examples 1 to 3 and Reference Experiments 1 and 2 was examined by the following procedure. The results are shown in Table 1. It was found that compounds I to III can efficiently absorb light at 313 nm.
Measurement procedure 0.01 g of the photobase generator was weighed into a 10 ml volumetric flask, and acetonitrile was added to the marked line and dissolved. 1 ml of this solution was weighed with a measuring pipette, diluted 10-fold with acetonitrile using a 10-ml volumetric flask, and this operation was repeated to prepare a 100-fold diluted solution of the stock solution.
This solution was put into a quartz cell (optical path length = 1 cm), and an absorption spectrum of 200 to 400 nm was measured with a spectrophotometer (UV-2500PC manufactured by Shimadzu Corporation). Using the absorbance obtained from the spectrum, the molar extinction coefficient was calculated from the following equation.
Molar extinction coefficient (ε) = absorbance × molecular weight / concentration (g / L)

Example 5
Photocuring test of episulfide compound 100 parts by weight of bis (2,3-epithiopropyl) sulfide, 2 parts by weight of photobase generator, 6 parts by weight of γ-butyrolactone and silicone oil KF-351 (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.2 After mixing parts by weight to obtain a uniform solution, this solution was coated on a glass substrate using a bar coater (No. 9).
This glass substrate was placed in a box with a quartz window, and nitrogen gas was allowed to flow through the box. After confirming that the oxygen concentration in the box was 0.2% or less, ultraviolet rays were irradiated for 1 minute using a metal halide lamp (30 mw / cm 2). Immediately thereafter, the glass substrate was immersed in tetrahydrofuran (THF), and after 30 minutes, it was taken out from THF and dried. The insolubilization rate was calculated from the following formula, and the curing rate was evaluated. The results are shown in Table 2.

Resin weight remaining on glass substrate
Insolubilization rate (%) = ――――――――――――――――― × 100
Weight of solution applied to glass substrate

It was found that the curing of the episulfide compound proceeds very rapidly when Compound I was used.

Claims (17)

A photobase generator represented by the following general formula (1).

Here, Ar is a phenyl, biphenyl, naphthyl, 4- (phenylthio) phenyl group, and these groups are unsubstituted or C1-C18 alkyl, C3-C18 alkenyl, C3-C18 alkynyl, C1- C18 haloalkyl, NO2, OH, CN, oR 1, SR 2, C (O) R 3, C (O) and mono- or poly-substituted by oR ₄ or halogen (wherein R _1, R _2, R ₃ , R ₄ is hydrogen or C1~C18 alkyl), R is hydrogen or C1~C18 alkyl, -A ⁺ is an ammonium ion selected from the following structural formulas (wherein, L is 1 or 0, R ₅ is C1-C5 alkyl),

X ⁻ is a borate anion, N, N-dimethyldithiocarbamate anion, N, N-dimethylcarbamate anion, thiocyanate anion or cyanate anion. The photobase generator according to claim 1, wherein Ar in the general formula (1) is phenyl. The photobase generator according to claim 1 or 2, wherein in the general formula (1), -A ⁺ is an ammonium ion selected from the following structural formula.

(Wherein L is 1 or 0, and R ₅ is C1-C5 alkyl.) The photobase generator according to any one of claims 1 to 3, wherein in the general formula (1), X ^- is a borate anion. At least one episulfide compound having at least two thiirane rings in the molecule and at least one general formula (1):

(Ar is a phenyl, biphenyl, naphthyl, 4- (phenylthio) phenyl group, and these groups are unsubstituted or C1-C18 alkyl, C3-C18 alkenyl, C3-C18 alkynyl, C1-C18 haloalkyl. , NO 2, OH, CN, OR ₁ , SR ₂ , C (O) R ₃ , C (O) OR _4, or monosubstituted or polysubstituted by halogen (wherein R ₁ , R ₂ , R ₃ , R ₄ is hydrogen or C1-C18 alkyl), R is hydrogen or C1-C18 alkyl, -A ⁺ is an ammonium ion selected from the following structural formulas (wherein L is 1 or 0, R ₅ is C1-C5 alkyl),

X ⁻ is a borate anion, N, N-dimethyldithiocarbamate anion, N, N-dimethylcarbamate anion, thiocyanate anion or cyanate anion. )
The curable composition characterized by including the photobase generator represented by these. 6. The curable composition according to claim 5, wherein Ar in the general formula (1) is phenyl. The curable composition according to claim 5 or 6, wherein -A ⁺ in the general formula (1) is an ammonium ion selected from the following structural formula.

(Wherein L is 1 or 0, and R ₅ is C1-C5 alkyl.) The curable composition according to any one of claims 5 to 7, wherein in the general formula (1), X ^- is a borate anion. The curable composition according to any one of claims 5 to 8, wherein the episulfide compound is represented by the following general formula (2).

(In Formula (2), R6 and R7 are each independently a hydrogen atom or a C1-C10 monovalent hydrocarbon group, and R8 and R9 are each independently a C1-C10 divalent hydrocarbon group. N is an integer from 0 to 4, and m is an integer from 0 to 6.) The curable composition according to claim 9, wherein the episulfide compound of the general formula (2) is bis (2,3-epithiopropyl) sulfide or bis (2,3-epithiopropyl) disulfide. Furthermore, a sensitizer is included, The curable composition in any one of Claims 5-10 characterized by the above-mentioned. The curable composition according to any one of claims 5 to 11, comprising a solvent capable of dissolving the photobase generator of the general formula (1). A method for curing an episulfide compound, wherein the curable composition according to any one of claims 5 to 12 is cured by irradiation with ultraviolet rays. The curing method according to claim 13, wherein the curable composition is heated and cured after being irradiated with ultraviolet rays. The curing method according to claim 13 or 14, wherein the ultraviolet irradiation is performed in an atmosphere having an oxygen concentration of 3% or less. The curing method according to claim 15, wherein the oxygen concentration is 0.3% or less. The curing method according to any one of claims 13 to 16, wherein the curing is performed in the presence of at least one strong base represented by the following formula.

(Wherein L is 1 or 0, R ₅ is C1-C5 alkyl)