JP2010106205A - Thermosetting resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermosetting resin composition which excels in the compatibility of each component, in which viscosity of the composition is reduced, the physical properties of a cured product obtained can be raised, and which can be used also for an application demanding severe colorless and transparent properties of sealing an optical semiconductor or the like. <P>SOLUTION: The thermosetting resin composition includes the following component (A) and component (B), and the mass ratio of both components, component (A)/component (B) is 20/80-80/20. The component (A) is a polysiloxane derivative which has two or more carboxyl groups and in which more than 10 mol% of a carboxyl group in a carboxyl group-containing polysiloxane of a specific conformation having a siloxane bond is blocked by reaction with a vinyl ether compound. The component (B) is an alicyclic ring type epoxy group containing a basket type silsesquioxane which has two or more alicyclic ring type epoxy groups and has a specific conformation having a cyclohexane ring and a siloxane bond. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a thermosetting resin composition used by thermosetting. More specifically, thermosetting is suitably used as an optical electronic member such as an optical semiconductor sealant, an electronic circuit sealant, an optical waveguide, an optical communication lens, an organic EL element sealant, and an optical film. The present invention relates to a resin composition.

  In recent years, for higher output and shorter wavelength of light sources using light-emitting diodes (LEDs) and other optical semiconductors, flat panel displays using liquid crystal, organic EL, etc. have higher definition, higher image quality, and higher viewing angle. Furthermore, the performance of optical and electronic parts has been remarkably advanced, such as higher frequency of electronic circuits and circuits / communications using light. In applications in these fields, a thermosetting resin composition (hereinafter abbreviated as a polysiloxane composition) using a polysiloxane compound having excellent colorless transparency has been used (for example, Patent Document 1). And 2). However, since the polysiloxane composition is generally low in hardness, there is a problem that foreign matter adheres to the surface, or a portion receiving a strong light amount such as a light emitting surface is damaged.

  A cage-type silsesquioxane is known as a substance having a hard structure while having a siloxane skeleton having high colorlessness and transparency, and application to fields such as electronics and photonics has been attempted. For example, Patent Document 3 discloses a resin composition containing oxetanyl-modified silsesquioxane, epoxy-modified disiloxane, and an acid anhydride curing agent. If a silsesquioxane compound that is solid, colorless and transparent and has curing reactivity is added as in this disclosed technique, the problem of low hardness is solved and a thermosetting resin composition having excellent light resistance is obtained.

  However, when a silsesquioxane compound having a high hydrogen bonding property is blended in a thermosetting resin composition, the compatibility with the polysiloxane compound is originally poor and the viscosity may increase. If the compatibility between the components is poor, in the process of producing a cured product, the components may be separated at the time of casting and standing, or even if the separation is not conspicuous, the reactive components may be unevenly distributed and appear to be poorly cured. Also, if the viscosity is high, it takes too much time during casting, material loss due to adhesion or the like occurs, or bubbles generated during casting are difficult to escape and voids are generated in the cured product. In Patent Document 3, the problem of compatibility is compromised by making the siloxane segment a disiloxane instead of a long chain, but the inherently excellent colorless and transparent of the polysiloxane compound derived from the long chain siloxane segment. It is difficult to make use of sex.

In view of the problems of the prior art as described above, the compatibility of each component is good, the viscosity of the composition is reduced, the physical properties of the resulting cured product are improved, and the excellent colorless transparency of the polysiloxane is achieved. There is a need for a thermosetting resin composition that can be utilized.
JP 2001-2922 A (pages 2 and 6) JP 2004-186168 A (page 2, page 3 and page 7) JP 2005-89601 A (second page)

  Therefore, the object of the present invention is excellent in compatibility of each component, the viscosity of the composition can be reduced, and the physical properties of the resulting cured product can be improved, such as sealing of an optical semiconductor, colorless and transparent An object of the present invention is to provide a thermosetting resin composition that can also be used for applications that require severe properties.

  In order to achieve the above object, the thermosetting resin composition of the present invention contains the following component (A) and component (B), and the mass ratio of both components is component (A) / component (B). = 20/80 to 80/20.

  Component (A): a compound having a plurality of carboxyl groups and having a structure represented by the following formula (1) and having at least 10 mol% of the carboxyl groups in the carboxyl group-containing polysiloxane is represented by the following formula (3): Polysiloxane derivatives blocked by reaction.

〔式（１）中、ａは０〜５０の整数、ｂは３〜３００の整数であり、Ｒ^１は炭素数が１〜６のアルキル基、Ｘ^１は下記式（２）で表される置換基であり、Ｘ^２はＲ^１又は下記式（２）で表される置換基であり（但し、ａ＝０のときＸ^２≠Ｒ^１）、Ｒ^１とＸ^１はそれぞれ同一でも異なっていてもよい。〕

In [Equation (1), a is an integer of 0 to 50, b is an integer of 3 to 300, ^{R 1} is an alkyl group having 1 to 6 carbon atoms, ^{X 1} is represented by the following formula (2) X ² is a substituent represented by R ¹ or the following formula (2) (provided that when a = 0, X ² ≠ R ¹ ), and R ¹ and X ¹ are the same or different. May be. ]

〔式（２）中、Ｒ^２は炭素数が１〜１０のアルキレン基又はアルキレンオキシアルキレン基、ｋは０又は１である。〕

Wherein (2), ^{R 2} is an alkylene group or alkylene oxyalkylene group having 1 to 10 carbon atoms, k is 0 or 1. ]

〔式（３）中、Ｒ^３は炭素数が１〜１０のアルキル基である。〕
成分（Ｂ）：脂環式エポキシ基を複数個有し、下記式（４）で示される構造を有する脂環式エポキシ基含有かご型シルセスキオキサン。

Wherein (3), ^{R 3} is an alkyl group having 1 to 10 carbon atoms. ]
Component (B): an alicyclic epoxy group-containing cage silsesquioxane having a plurality of alicyclic epoxy groups and having a structure represented by the following formula (4).

〔式（４）中、Ｒ^４は下記式（５）で示される脂環式エポキシ基を有する基、Ｒ^５は下記式（６）で示されるアルコキシシリル基を有する基、Ｒ^６は置換若しくは非置換のアルキル基又は水素、ｒは６、８、１０及び１２から選ばれた数、ｐは２〜ｒの整数及びｑは０〜（ｒ−ｐ）の整数を表す。〕

[In the formula (4), R ⁴ is a group having an alicyclic epoxy group represented by the following formula (5), R ⁵ is a group having an alkoxysilyl group represented by the following formula (6), and R ⁶ is substituted or An unsubstituted alkyl group or hydrogen, r is a number selected from 6, 8, 10, and 12, p is an integer of 2 to r, and q is an integer of 0 to (rp). ]

〔式（５）において、Ｒ^７は炭素数が１〜１０のアルキレン基又はアルキレンオキシアルキレン基である。〕

[In Formula (5), R < ⁷ > is a C1-C10 alkylene group or alkyleneoxyalkylene group. ]

〔式（６）において、Ｒ^８は炭素数が１〜１０のアルキレン基又はアルキレンオキシアルキレン基、Ｒ^９は炭素数１〜４のアルキル基、Ｒ^１０は炭素数１〜４のアルキル基であり、ｍは１〜３の整数である。〕

[In Formula (6), R ⁸ is an alkylene group or alkyleneoxyalkylene group having 1 to 10 carbon atoms, R ⁹ is an alkyl group having 1 to 4 carbon atoms, and R ¹⁰ is an alkyl group having 1 to 4 carbon atoms. , M is an integer of 1 to 3. ]

According to the present invention, the following effects can be exhibited.
In the thermosetting resin composition of the present invention, a polysiloxane derivative in which 10 mol% or more of carboxyl groups are blocked as a component (A) and an alicyclic epoxy group-containing cage silsesquioxane as a component (B). And the mass ratio of both components is set to (A) / (B) = 20/80 to 80/20. Since the carboxyl group in the component (A) polysiloxane derivative is blocked (latent), the hydrogen bond based on the carboxyl group is relaxed and the affinity between the component (A) and the component (B) is improved. In addition, the viscosity is improved.

  When the thermosetting resin composition is cured with heat or light, a plurality of carboxyl groups generated by thermal dissociation from the blocked carboxyl group of component (A) and a plurality of alicyclic components of component (B) A cured product is obtained by reaction with an epoxy group. In this cured product, the physical properties of the cured product are improved based on the improvement of the compatibility between the component (A) and the component (B), and a siloxane bond having a high binding energy is mainly used. It is thought that the colorless transparency of the is improved. Furthermore, since the carboxyl group exhibits a rigid structure by cross-linking reaction with an alicyclic epoxy group, and the silsesquioxane skeleton also exhibits a rigid structure, the hardness of the cured product is increased.

  Therefore, the thermosetting resin composition is excellent in the compatibility of each component, the viscosity of the composition is reduced, and the physical properties of the resulting cured product can be improved. It can also be used for applications that demand strict colorless transparency.

In the following, embodiments that are considered to be the best of the present invention will be described in detail.
The thermosetting resin composition of the present embodiment contains the following component (A) polysiloxane derivative and component (B) alicyclic epoxy group-containing cage silsesquioxane, and the mass ratio of both components Is component (A) / component (B) = 20/80 to 80/20. The thermosetting resin composition can improve the compatibility of each component and the viscosity of the composition, and can improve the physical properties of a cured product obtained by curing the thermosetting resin composition. It can be suitably used for applications that require strict colorless transparency, such as semiconductor sealing. Next, component (A) polysiloxane derivative, component (B) alicyclic epoxy group-containing cage silsesquioxane, ratio of components (A) and component (B), and thermosetting resin composition Curing of will be described in order.
<Polysiloxane derivative of component (A)>
The polysiloxane derivative of the component (A) has a plurality (two or more) of carboxyl groups, and 10 mol% or more of the carboxyl groups in the carboxyl group-containing polysiloxane having the structure represented by the following formula (1) is It is a polysiloxane derivative blocked by reaction with a vinyl ether compound represented by the formula (3). By blocking the carboxyl group in the polysiloxane derivative of the component (A), the affinity between the component (A) and the component (B) is increased, and the viscosity of the thermosetting resin composition is improved. And the physical properties of the cured product can be improved. When the ratio of blocking is less than 10 mol%, the effect based on blocking becomes insufficient, and the desired cured product cannot be obtained. In addition, the polysiloxane derivative of the component (A) is not limited as long as 10 mol% or more of the carboxyl groups are blocked, and may be included. Therefore, the composition obtained by blocking the carboxyl group of the carboxyl group-containing polysiloxane can be blended with a carboxyl group-containing polysiloxane that has not been blocked to adjust the ratio of the blocked one. .

〔式（１）中、ａは０〜５０の整数、ｂは３〜３００の整数であり、Ｒ^１は炭素数が１〜６のアルキル基、Ｘ^１は下記式（２）で表される置換基であり、Ｘ^２はＲ^１又は下記式（２）で表される置換基であり（但し、ａ＝０のときＸ^２≠Ｒ^１）、Ｒ^１とＸ^１はそれぞれ同一でも異なっていてもよい。〕
式（１）におけるＲ^１は、好ましくは１〜３のアルキル基であり、Ｒ^１は全て同一でも異なっていても良い。Ｒ^１がアルキル基ではなく芳香族炭化水素基や脂環族炭化水素基であると、耐光性が低下する。Ｒ^１の炭素数が６を上回る場合には、有機成分としての炭化水素が増大するため硬化物の無色透明性が低下する。

In [Equation (1), a is an integer of 0 to 50, b is an integer of 3 to 300, ^{R 1} is an alkyl group having 1 to 6 carbon atoms, ^{X 1} is represented by the following formula (2) X ² is a substituent represented by R ¹ or the following formula (2) (provided that when a = 0, X ² ≠ R ¹ ), and R ¹ and X ¹ are the same or different. May be. ]
R ¹ in Formula (1) is preferably an alkyl group of 1 to 3, and R ¹ may be all the same or different. When R ¹ is not an alkyl group but an aromatic hydrocarbon group or an alicyclic hydrocarbon group, light resistance decreases. When the carbon number of R ¹ exceeds 6, hydrocarbons as organic components increase, and the colorless transparency of the cured product decreases.

Specific examples of R ¹ include linear alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, and hexyl; isopropyl, isobutyl, sec-butyl, t-butyl, and isopentyl. And branched alkyl groups such as a group, 3-methylbutyl group, sec-pentyl group, neopentyl group, t-pentyl group, isohexyl group, sec-hexyl group and t-hexyl group. Among these, a methyl group is particularly preferable from the viewpoint of colorless transparency.

X ¹ in the formula (1) is R ¹ or a substituent represented by the following formula (2). However, at least two in X ¹ are preferably substituents represented by the following formula (2).

〔式（２）中、Ｒ^２は炭素数が１〜１０のアルキレン基又はアルキレンオキシアルキレン基、ｋは０又は１である。〕
Ｒ^２の炭素数が１０を上回る場合には、有機成分が増大するため硬化物の無色透明性が低下する。Ｒ^２として具体的には例えば、メチレン基、エチレン基、プロピレン基、ブチレン基などのアルキレン基（−Ｒ−）；メチレンオキシメチレン基、メチレンオキシエチレン基、メチレンテトラオキシメチレン基等のアルキレンオキシアルキレン基（−ＲＯＲ−）が挙げられる。これらのＲ^２のうち、炭素数２〜５のアルキレン基が好ましい。

Wherein (2), ^{R 2} is an alkylene group or alkylene oxyalkylene group having 1 to 10 carbon atoms, k is 0 or 1. ]
When the carbon number of R ² exceeds 10, the organic component increases, so that the colorless transparency of the cured product is lowered. Specific examples of R ² include alkylene groups (—R—) such as methylene group, ethylene group, propylene group, and butylene group; alkyleneoxyalkylene groups such as methyleneoxymethylene group, methyleneoxyethylene group, and methylenetetraoxymethylene group. A group (-ROR-). Among these R ² , an alkylene group having 2 to 5 carbon atoms is preferable.

Formula (2) is a structure in which a carboxylic acid is substituted on the cyclohexane ring. By having a cyclohexane ring structure, rigidity can be imparted to the highly flexible polysiloxane, and the hardness of the cured product, and hence the surface non-tackiness, is improved. Wherein ^{X 1} is _- in the case of _(CH 2) n -COOH, that n is preferably an integer of 5 to 15, as an example _{- (CH 2) 8 -COOH,} - (CH 2) 10 _{-COOH, - (CH 2) 12} -COOH , and the like.

The number of repeating units of the carboxyl group-containing segment in the carboxyl group-containing polysiloxane, that is, a in the formula (1) is 0 to 50, preferably 0 to 10. When a is 0, it means that X ² ≠ R ¹ and has carboxyl groups only at both ends. When a is 1-50, it will have a carboxyl group in the side chain, and a denser cross-linked structure can be taken, which is preferable from the viewpoint of the hardness of the cured product.

  When a exceeds 50, physical properties such as hardness of the cured product are good, but the colorless transparency is lowered. This is because the acid equivalent in the carboxyl group-containing polysiloxane is reduced and the organic component is increased. This is because the bond (carbon-carbon bond or carbon-oxygen bond) in the organic component has a lower bond energy than the siloxane bond and is easily decomposed. In addition, an acid equivalent means mass required in order to obtain the carboxyl group production amount per mol of the carboxyl group-containing polysiloxane of the formula (1).

  The number of repeating units of the carboxyl group-free segment in the carboxyl group-containing polysiloxane, that is, b in the formula (1) is 3 to 300, preferably 9 to 150. When b is less than 3, the content of siloxane in the carboxyl group-containing polysiloxane decreases and the organic component increases, so that the colorless transparency of the cured product decreases. When b exceeds 300, the molecular weight of the carboxyl group-containing polysiloxane is increased and the viscosity of the thermosetting resin composition is increased, which may cause problems in compatibility with the component (B) and workability. .

  The ratio (a) / (b) of [carboxyl group-containing segment (a)] / [carboxyl group-free segment (b)] in the carboxyl group-containing polysiloxane represented by formula (1) of component (A) is as follows: Usually, it is 0.01 to 5, preferably 0.03 to 3. When the ratio (a) / (b) is within this range, the acid equivalent of the carboxyl group-containing polysiloxane becomes a sufficient value, and good curability is obtained. When (a) / (b) is smaller than 0.01, the acid equivalent is large and the curability of the thermosetting resin composition may be insufficient. On the other hand, when (a) / (b) is larger than 5, the acid equivalent is small, and the transparency of the cured product may be insufficient.

The carboxyl group-containing polysiloxane is obtained by reacting a carbinol group-containing precursor in which the substituent X ¹ corresponding to the formula (2) is —R ² —OH with the cyclohexane polycarboxylic acid anhydride in the same mole in the formula (1). It is obtained quantitatively by the ring-opening half esterification reaction. Specific examples of the cyclohexane polycarboxylic acid anhydride used when synthesizing the carboxyl group-containing polysiloxane include cyclohexane dicarboxylic acid anhydride and cyclohexane tricarboxylic acid anhydride. One of these cyclohexane polycarboxylic acid anhydrides may be used alone, or two or more thereof may be used in combination.

  The carbinol group-containing polysiloxane is preferably functional at both terminals and having a number average molecular weight (Mn) of 1000 to 20000. When this number average molecular weight is lower than 1000, the siloxane content decreases, and the organic component increases accordingly, so that the colorless transparency of the cured product may decrease. On the other hand, when the number average molecular weight is higher than 20000, the viscosity of the thermosetting resin composition increases, which may impair the coatability.

  In the method for producing a carboxyl group-containing polysiloxane, blending is performed so that 1 mol of the acid anhydride group of cyclohexane polycarboxylic acid anhydride reacts with respect to 1 mol of hydroxyl group of the carbinol group-containing polysiloxane. The reaction conditions are usually set in the temperature range of room temperature to 200 ° C. and 1 to 100 hours.

  Next, the vinyl ether compound is a compound represented by the following formula (3), and a carboxyl group of the polysiloxane represented by the formula (1) is blocked by a hemiacetal esterification reaction ( (Latent or protected). Thus, by blocking the carboxyl group of the component (A), the component (A) can be reduced in viscosity, and compatibility and solubility with the component (B) can be improved. Further, the produced hemiacetal ester undergoes a thermal dissociation reaction accompanied by elimination of the vinyl ether compound by heating, and the original carboxyl group is regenerated.

〔式（３）中、Ｒ^３は炭素数が１〜１０のアルキル基である。〕
係るビニルエーテル化合物（アルキルビニルエーテル）として具体的には、イソプロピルビニルエーテル、エチルビニルエーテル、ブチルビニルエーテル、ヘキシルビニルエーテル、オクチルビニルエーテル等が挙げられる。このビニルエーテル化合物のアルキル基としては１級アルキル基より２級アルキル基が好ましく、ビニルエーテル化合物として具体的にはイソプロピルビニルエーテルが好ましい。
＜成分（Ｂ）の脂環式エポキシ基含有かご型シルセスキオキサン＞
脂環式エポキシ基含有かご型シルセスキオキサンは、脂環式エポキシ基を複数個有し、多面体構造を有するシロキサンであって、下記の式（４）で示される構造を有している。すなわち、脂環式エポキシ基含有かご型シルセスキオキサンは、下記の式（７）で示されるシルセスキオキサン骨格に、下記の式（５）で示される脂環式エポキシ基を有する置換基、下記の式（６）で示されるアルコキシシリル基を有する置換基、及び置換又は非置換のアルキル基を有する置換基をそれぞれｐ、ｑ、及びｒ−ｐ−ｑ個有するかご型シルセスキオキサンである。

Wherein (3), ^{R 3} is an alkyl group having 1 to 10 carbon atoms. ]
Specific examples of the vinyl ether compound (alkyl vinyl ether) include isopropyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, hexyl vinyl ether, and octyl vinyl ether. As the alkyl group of the vinyl ether compound, a secondary alkyl group is preferable to a primary alkyl group, and specifically, isopropyl vinyl ether is preferable as the vinyl ether compound.
<Component (B) alicyclic epoxy group-containing cage silsesquioxane>
The alicyclic epoxy group-containing cage silsesquioxane is a siloxane having a plurality of alicyclic epoxy groups and a polyhedral structure, and has a structure represented by the following formula (4). That is, the alicyclic epoxy group-containing cage silsesquioxane is a substituent having an alicyclic epoxy group represented by the following formula (5) on the silsesquioxane skeleton represented by the following formula (7). A cage-type silsesquioxane having p, q, and rpq substituents each having an alkoxysilyl group represented by the following formula (6) and a substituted or unsubstituted alkyl group: It is.

〔式（４）中、Ｒ^４は下記式（５）で示される脂環式エポキシ基を有する基、Ｒ^５は下記式（６）で示されるアルコキシシリル基を有する基、Ｒ^６は置換若しくは非置換のアルキル基又は水素、ｒは６、８、１０及び１２から選ばれた数、ｐは２〜ｒの整数及びｑは０〜（ｒ−ｐ）の整数を表す。〕

[In the formula (4), R ⁴ is a group having an alicyclic epoxy group represented by the following formula (5), R ⁵ is a group having an alkoxysilyl group represented by the following formula (6), and R ⁶ is substituted or An unsubstituted alkyl group or hydrogen, r is a number selected from 6, 8, 10, and 12, p is an integer of 2 to r, and q is an integer of 0 to (rp). ]

〔式（５）において、Ｒ^７は炭素数が１〜１０のアルキレン基又はアルキレンオキシアルキレン基である。〕
式（５）におけるＲ^７としては、炭素数が１〜３のアルキレン基であることが好ましく、該アルキレン基として具体的にはエチレン基〔−（ＣＨ_２）_２−〕が好ましい。

[In Formula (5), R < ⁷ > is a C1-C10 alkylene group or alkyleneoxyalkylene group. ]
R ⁷ in Formula (5) is preferably an alkylene group having 1 to 3 carbon atoms. Specifically, the alkylene group is preferably an ethylene group [— (CH ₂ ) ₂ —].

〔式（６）において、Ｒ^８は炭素数が１〜１０のアルキレン基又はアルキレンオキシアルキレン基、Ｒ^９は炭素数１〜４のアルキル基、Ｒ^１０は炭素数１〜４のアルキル基であり、ｍは１〜３の整数である。〕
式（６）におけるＲ^８としては、炭素数が１〜３のアルキレン基であることが好ましく、係るアルキレン基としてはエチレン基が好ましい。Ｒ^９及びＲ^１０としては、炭素数が１〜３のアルキル基であることが好ましく、具体的にはメチル基（−ＣＨ_３）が好ましい。

[In Formula (6), R ⁸ is an alkylene group or alkyleneoxyalkylene group having 1 to 10 carbon atoms, R ⁹ is an alkyl group having 1 to 4 carbon atoms, and R ¹⁰ is an alkyl group having 1 to 4 carbon atoms. , M is an integer of 1 to 3. ]
R ⁸ in Formula (6) is preferably an alkylene group having 1 to 3 carbon atoms, and the alkylene group is preferably an ethylene group. R ⁹ and R ¹⁰ are preferably an alkyl group having 1 to 3 carbon atoms, and specifically, a methyl group (—CH ₃ ) is preferable.

As the substituted or unsubstituted alkyl group of R ⁶ in formula (4), an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 5 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms such as a phenyl group, The C1-C20 hydrocarbon group containing an ether bond, the C1-C20 hydrocarbon group containing an ester bond, or the C1-C12 hydrocarbon group containing a triorganosiloxy group is mentioned.

  Specifically, examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group. . Examples of the cycloalkyl group having 5 to 12 carbon atoms include a cyclopentyl group, a cyclohexyl group, and a norbornyl group. The alkylene group having 1 to 12 carbon atoms containing a triorganosiloxy group is usually a straight chain having 1 to 12 carbon atoms, preferably about 1 to 6 carbon atoms such as a methylene group, an ethylene group, a propylene group, or a butylene group. Examples thereof include a triorganosiloxy-substituted alkyl group in which a triorganosiloxy group is bonded to a chain, cyclic or branched alkylene group. Among these, it is preferable that it is a C1-C10 alkyl group.

  R in the formula (4) is a number selected from 6, 8, 10 and 12, and is preferably 8. p is an integer of 2 to r, preferably an integer of 4 to r. When r is smaller than 2, a crosslinked structure is not formed in the cured product, and the cured product does not have the desired physical properties. q is an integer of 0 to (rp), and when it is an integer of 1 or more, in addition to the reaction of a carboxyl group and an epoxy group, a crosslinked structure is formed even by a bond between hydrolysis and polycondensation of alkoxy groups. Is possible, and physical properties such as hardness are improved.

As a method for synthesizing the above cage silsesquioxane, a method of introducing a substituent into a synthesized cage structure of a cage silsesquioxane, or a hydrolysis of a trifunctional organosilicon monomer having a substituent. Although methods are known, any of them may be used. The skeleton structure of cage silsesquioxanes can be synthesized by various methods, for example, see Chem. Rev. 1995, 95, 1431 and J.H. Am. Che. Soc. 1989, 111, 1741 or Organometallics. 1991, 10, 2526 and the like. Further, for example, an alkyl group can be introduced onto the silicon at the apex by using a hydrosilylation reaction to octakis (hydridosilsesquioxane) in which each apex of the hexahedron is made of silicon and each side is made of oxygen (for example, (See Japanese Patent No. 3020164).
<Ratio of content of component (A) and component (B)>
In the thermosetting resin composition, the mass ratio of component (A) to component (B) is component (A) / component (B) = 20/80 to 80/20, preferably 30/70 to 75/25. It is. If the content of the component (A) / component (B) = 20/80 and the content of the polysiloxane derivative of the component (A) becomes too small, the curability of the thermosetting resin composition becomes insufficient and the composition is cured. The hardness and colorless transparency of the object are reduced. On the other hand, if the content ratio of the component (A) / component (B) = 80/20 and the content of the polysiloxane derivative of the component (A) becomes too large, the alicyclic epoxy group-containing cage-type sill of the component (B) Since the ratio of sesquioxane decreases, the rigid properties of the cage silsesquioxane skeleton are hardly expressed, and the physical properties such as hardness of the cured product deteriorate.

  Furthermore, the compounding amount of the polysiloxane derivative of component (A) and the alicyclic epoxy group-containing cage silsesquioxane of component (B) is (equivalent of carboxyl group derived from polysiloxane derivative) / (alicyclic) The ratio (equivalent ratio) of the epoxy group derived from the epoxy group-containing cage silsesquioxane is usually 0.2 to 2.0, preferably 0.7 to 1.2, more preferably 0.8 to It is adjusted to 1.1. When the ratio is less than 0.2, the adhesiveness of the cured product may be reduced. On the other hand, when the ratio is more than 2.0, curing failure may occur due to excess carboxylic acid, or the transparency of the cured product may be reduced. Or drop.

  By using the polysiloxane derivative of component (A) and the alicyclic epoxy group-containing cage-type silsesquioxane of component (B) in the above proportions, each component has excellent compatibility and solubility, and the viscosity of the composition The thermosetting resin composition which can improve physical properties, such as hardness of the obtained hardened | cured material and colorless transparency, is obtained. About the mechanism which can express these outstanding performances, it estimates as follows.

  That is, since the carboxyl group in component (A) is blocked, hydrogen bonding based on the carboxyl group is suppressed, the affinity between component (A) and component (B) is improved, and the thermosetting resin composition The viscosity of the object is reduced. Therefore, it is thought that the thermosetting resin composition has good curability and the physical properties of the cured product are enhanced. Furthermore, polysiloxane and silsesquioxane are generally composed of siloxane bonds (silicon-oxygen bonds), and since these siloxane bonds have higher atomic bond energy than carbon-carbon bonds, the hardness of the cured product. It is thought that physical properties such as colorless transparency can be enhanced.

In addition, the thermosetting resin composition contains a polysiloxane derivative and an alicyclic epoxy group-containing cage-type silsesquioxane, and since the siloxane content is high, the hardness of the cured product, colorless and transparent The physical properties such as properties can be improved. In addition, the carboxyl group derived from the polysiloxane derivative and the alicyclic epoxy group of the alicyclic epoxy group-containing cage silsesquioxane are bonded to the cyclohexane ring, resulting in a rigid structure. In addition, the cage silsesquioxane skeleton also has a rigid structure, and it is considered that physical properties such as hardness are enhanced by a synergistic effect thereof.
<Curing of thermosetting resin composition>
By thermosetting or photocuring the thermosetting resin composition, a cured product used as an optical semiconductor sealing agent or the like is obtained. In this case, the thermosetting resin composition adds an acid catalyst for the purpose of accelerating the curing reaction when cured at a low temperature in a short time and imparting good chemical performance and physical performance to the cured product. May be. Examples of the acid catalyst include protonic acids such as phosphoric acid, sulfonic acid, and boric acid; boron trifluoride (BF ₃ ), ferric chloride (FeC1 ₃ ), stannic chloride (SnC1 ₄ ), aluminum chloride (A1C1) ₃ ), Lewis acids such as zinc chloride (ZnC1 ₂ ) and organometallic complexes. Of these, organometallic complexes are particularly preferred from the viewpoints of curability and transparency. As the acid catalyst, any one or two or more of the above compounds can be used in appropriate combination.

  The addition amount of this acid catalyst is normally set in the range of 0.01 to 10 parts by mass with respect to 100 parts by mass of the total solid content of the thermosetting resin composition. When the addition amount of the acid catalyst is less than 0.01 parts by mass, the catalytic effect is not sufficiently exhibited, and when it exceeds 10 parts by mass, the obtained cured product may be colored or the water resistance may be lowered. Is not preferable.

  The thermosetting resin composition can be used after diluted with an organic solvent. Examples of the organic solvent include aromatic hydrocarbons, alicyclic hydrocarbons, esters, halogen-containing aliphatic hydrocarbons, ketones, ethers, and the like. These organic solvents may be used individually by 1 type, and may be used in combination of 2 or more types as appropriate. The usage-amount of an organic solvent is 30 mass parts or less normally with respect to 100 mass parts of thermosetting resin compositions, Preferably it is 7 mass parts or less.

  In addition, for the thermosetting resin composition, a coupling agent, an antioxidant, an ultraviolet absorber, a visible light absorber, an infrared absorber, a modifier, a filler, a flame retardant, a thixotropic agent, etc., as necessary. These other additives can be blended according to conventional methods. Other additives may be used alone or in combination of two or more. Moreover, the addition amount is 0.01-10 mass parts normally with respect to 100 mass parts of total solid content of a thermosetting resin composition.

  When using a thermosetting resin composition as a sealing agent, it can implement by thermosetting or photocuring this thermosetting resin composition. In that case, the thermosetting resin composition is applied and cured by an overcoat method, a dip coat method, or the like, or the composition is placed in a container and the optical semiconductor element is dipped therein and cured as it is. For example, the optical semiconductor element can be sealed.

Hereinafter, the embodiment will be described more specifically with reference to synthesis examples, examples, and comparative examples.
[Reference Synthesis Example 1, Synthesis of carboxyl group-containing polysiloxane (S-1)]
In a 300 mL four-round flask equipped with a thermometer, a reflux condenser, and a stirrer, 164.1 g of a carbinol group-containing polysiloxane (number average molecular weight 1810) represented by the following formula (8) and cyclohexanetricarboxylic anhydride 35 Was added at a reaction temperature of 140 ° C. After reacting at the same temperature for 6 hours, the reaction was terminated, and the mixture was allowed to cool and then collected. As a result, a colorless and transparent carboxyl group-containing polysiloxane represented by the following formula (9) (S-1, carboxyl groups are both terminal types, acid equivalent = 533 g / mol) was obtained in a yield of 91%.

〔参考合成例２、カルボキシル基含有ポリシロキサン（Ｓ−２）の合成〕
温度計、還流冷却器及び撹拌機を備えた３００ｍＬの４つロフラスコに、下記式（１０）で表されるカルビノール基含有ポリシロキサン（数平均分子量１１２２０）１８０．８ｇ及びシクロヘキサントリカルボン酸無水物１９．２ｇを投入し、反応温度１４０℃で付加反応を行った。同温度で６時間反応させた後、反応終了とし、放冷させた後に回収した。その結果、下記式（１１）で表される無色透明のカルボキシル基含有ポリシロキサン（Ｓ−２、カルボキシル基が側鎖型、酸当量＝１０３４ｇ／ｍｏｌ）を９２％の収率で得た。

[Reference Synthesis Example 2, Synthesis of carboxyl group-containing polysiloxane (S-2)]
In a 300 mL four-round flask equipped with a thermometer, a reflux condenser, and a stirrer, 180.8 g of a carbinol group-containing polysiloxane (number average molecular weight 11220) represented by the following formula (10) and cyclohexanetricarboxylic anhydride 19 .2 g was added and an addition reaction was performed at a reaction temperature of 140.degree. After reacting at the same temperature for 6 hours, the reaction was terminated, and the mixture was allowed to cool and then collected. As a result, a colorless and transparent carboxyl group-containing polysiloxane represented by the following formula (11) (S-2, carboxyl group is a side chain type, acid equivalent = 1034 g / mol) was obtained in a yield of 92%.

〔合成例１、ポリシロキサン誘導体（Ａ−１）の合成〕
温度計、還流冷却器及び撹拌機を備えた３００ｍＬの４つロフラスコに、参考合成例１で得たカルボキシル基含有ポリシロキサン（Ｓ−１）を１２９．２（０．２４ｍｏｌ）、イソプロピルビニルエーテル（ｉＰＶＥ）を２０．８ｇ（０．２４ｍｏｌ）、及びメチルエチルケトン（ＭＥＫ）１００ｇを仕込み、７５℃を保ちながら均一になるまで攪拌した。次いで、この混合物を９０℃に昇温し４時間反応させた。反応液のＧＣ（ガスクロマトグラフ）測定によるイソプロピルビニルエーテルの消失から転化率は９９．５％であった。エバポレーターで反応液からＭＥＫを留去し、ヘキサンで２回洗浄後、商品名キョーワード５００〔陰イオン吸着剤、協和化学工業（株）製〕を用いて吸着処理を行い、カルボキシル基含有ポリシロキサンのカルボキシル基が全ブロック化されている、目的のポリシロキサン誘導体（Ａ−１）が得られた。測定された酸当量６２３ｇ／ｍｏｌからも９９％以上の純度で完全ブロック化物が得られていることが確認された。収量は１３６ｇ、収率は９０％であった。
〔合成例２〜５及び比較合成例１、ポリシロキサン誘導体（Ａ−２〜５およびＡ’−１）の合成〕
合成例１におけるＳ−１、またはＳ−２と、ｉＰＶＥまたはｎ−ブチルビニルエーテル（ｎＢＶＥ）を用い、合成例１と同じ方法により、ブロック化剤であるビニルエーテルの仕込みモル比率を種々の割合で減じることにより、部分ブロック化物であるポリシロキサン誘導体（Ａ−２〜５）を得た。仕込み組成と反応結果を合わせて表１に示す。

[Synthesis Example 1, Synthesis of Polysiloxane Derivative (A-1)]
129.2 (0.24 mol) of carboxyl group-containing polysiloxane (S-1) obtained in Reference Synthesis Example 1 and isopropyl vinyl ether (iPVE) were added to a 300 mL four-round flask equipped with a thermometer, a reflux condenser and a stirrer. ) Was charged with 20.8 g (0.24 mol) and 100 g of methyl ethyl ketone (MEK), and the mixture was stirred while maintaining 75 ° C. until uniform. Subsequently, this mixture was heated to 90 ° C. and reacted for 4 hours. From the disappearance of isopropyl vinyl ether by GC (gas chromatograph) measurement of the reaction solution, the conversion rate was 99.5%. MEK is distilled off from the reaction solution with an evaporator, washed twice with hexane, and subjected to adsorption treatment using a trade name KYOWARD 500 [anion adsorbent, manufactured by Kyowa Chemical Industry Co., Ltd.], and carboxyl group-containing polysiloxane The target polysiloxane derivative (A-1) in which all the carboxyl groups were blocked was obtained. From the measured acid equivalent of 623 g / mol, it was confirmed that a completely blocked product was obtained with a purity of 99% or more. The yield was 136 g, and the yield was 90%.
[Synthesis Examples 2 to 5 and Comparative Synthesis Example 1, Synthesis of Polysiloxane Derivatives (A-2 to 5 and A′-1)]
Using S-1 or S-2 in Synthesis Example 1 and iPVE or n-butyl vinyl ether (nBVE), the charge molar ratio of vinyl ether as a blocking agent is reduced at various ratios by the same method as Synthesis Example 1. As a result, polysiloxane derivatives (A-2 to 5) which were partially blocked products were obtained. The charged composition and reaction results are shown together in Table 1.

〔合成例６、脂環式エポキシ基含有かご型シルセスキオキサン（ＳＱ−１）の合成〕
温度計、還流冷却器及び撹拌機を備えた３００ｍＬの４つロフラスコに、窒素雰囲気下、オクタキス［ヒドリドジメチルシロキシ］シルセスキオキサン（ＯＨＳＳ）を１０．１８ｇ（１０ｍｍｏｌ）、４−ビニルシクロヘキセン−１，２−エポキシドを４．９７ｇ（４０ｍｍｏｌ）、１−オクテンを４．４９ｇ（４０ｍｍｏｌ）及び脱水トルエンを３０ｇ投入した。ＯＨＳＳを溶解させた後、触媒として１，３−ジビニル−１，１，３，３−テトラメチルジシロキサン白金０．１Ｍキシレン溶液を０．０３ｍＬ加えて、７０℃で３時間反応させた。その後、活性炭によって触媒を取り除き、溶媒を留去することにより、無色透明粘性液体１８．７ｇ（９．５ｍｍｏｌ）を得た。

[Synthesis Example 6, synthesis of caged silsesquioxane (SQ-1) containing alicyclic epoxy group]
10.18 g (10 mmol) of octakis [hydridodimethylsiloxy] silsesquioxane (OHSS), 4-vinylcyclohexene-1 in a 300 mL four-neck flask equipped with a thermometer, a reflux condenser and a stirrer under a nitrogen atmosphere , 2-epoxide 4.97 g (40 mmol), 1-octene 4.49 g (40 mmol) and dehydrated toluene 30 g. After OHSS was dissolved, 0.03 mL of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane platinum 0.1M xylene solution was added as a catalyst and reacted at 70 ° C. for 3 hours. Thereafter, the catalyst was removed with activated carbon, and the solvent was distilled off to obtain 18.7 g (9.5 mmol) of a colorless transparent viscous liquid.

  As a result of measuring the obtained reaction product by 1H-NMR spectrum, it was confirmed that it was a cage-type silsesquioxane (SQ-1) represented by the following formula (12). The yield of SQ-1 obtained was 95%, and the epoxy equivalent was 491 g / mol.

〔合成例７、脂環式エポキシ基含有かご型シルセスキオキサン（ＳＱ−２）の合成〕
合成例６において、１−オクテン４．４９ｇ（４０ｍｍｏｌ）をビニルトリメトキシシラン５．９２ｇ（４０ｍｍｏｌ）に代えたほかは、合成例６と同様に実施し、無色透明粘性液体１８．７ｇ（９．５ｍｍｏｌ）を得た。

[Synthesis Example 7, Synthesis of cage-type silsesquioxane (SQ-2) containing alicyclic epoxy group]
The same procedure as in Synthesis Example 6 was performed, except that 4.49 g (40 mmol) of 1-octene was replaced with 5.92 g (40 mmol) of vinyltrimethoxysilane in Synthesis Example 6, and 18.7 g (9. 5 mmol) was obtained.

  As a result of measuring the obtained reaction product with a 1H-NMR spectrum, it was confirmed that it was a cage silsesquioxane (SQ-2) represented by the following formula (13). The yield of SQ-2 obtained was 95%, and the epoxy equivalent was 527 g / mol.

〔比較合成例１、エポキシ基含有かご型シルセスキオキサン（ＳＱ’−１）の合成〕
温度計、還流冷却器及び撹拌機を備えた３００ｍＬの４つロフラスコに、窒素雰囲気下、オクタキス［ヒドリドジメチルシロキシ］シルセスキオキサン（ＯＨＳＳ）を１０．１８ｇ（１０ｍｍｏｌ）、アリルグリシジルエーテルを４．５７ｇ（４０ｍｍｏｌ）、１−オクテンを４．４９ｇ（４０ｍｍｏｌ）及び脱水トルエンを３０ｇ投入した。ＯＨＳＳを溶解させた後、触媒として１，３−ジビニル−１，１，３，３−テトラメチルジシロキサン白金０．１Ｍキシレン溶液を０．０３ｍＬ加えて、７０℃で３時間反応させた。その後、活性炭で触媒を取り除き、溶媒を留去することにより、無色透明粘性液体１８．１ｇ（９．５ｍｍｏｌ）を得た。

[Comparative Synthesis Example 1, Synthesis of epoxy group-containing cage silsesquioxane (SQ′-1)]
In a 300 mL four-round flask equipped with a thermometer, a reflux condenser, and a stirrer, under a nitrogen atmosphere, 10.18 g (10 mmol) of octakis [hydridodimethylsiloxy] silsesquioxane (OHSS) and 4. allyl glycidyl ether were added. 57 g (40 mmol), 4.49 g (40 mmol) of 1-octene and 30 g of dehydrated toluene were added. After OHSS was dissolved, 0.03 mL of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane platinum 0.1M xylene solution was added as a catalyst and reacted at 70 ° C. for 3 hours. Thereafter, the catalyst was removed with activated carbon, and the solvent was distilled off to obtain 18.1 g (9.5 mmol) of a colorless transparent viscous liquid.

  As a result of measuring the obtained reaction product with a 1H-NMR spectrum, it was confirmed that it was a cage silsesquioxane (SQ′-1) represented by the following formula (14). The yield of SQ'-1 was 94% and the epoxy equivalent was 481 g / mol.

〔試験方法〕
下記に示す実施例及び比較例における粘度、相溶性、色差及び硬度の試験方法を次に示す。
（１）粘度
常法に従って粘度計により熱硬化性樹脂組成物の粘度（ｍＰａ・ｓ）を測定した。
（２）相溶性
高さ１８ｃｍ、内容量５０ｍＬの円筒状をなすガラス製容器中に熱硬化性樹脂組成物を１時間静置後、相溶性を目視により測定し、次の基準で評価した。

〔Test method〕
Test methods for viscosity, compatibility, color difference and hardness in the following examples and comparative examples are shown below.
(1) Viscosity The viscosity (mPa · s) of the thermosetting resin composition was measured with a viscometer according to a conventional method.
(2) Compatibility After the thermosetting resin composition was allowed to stand in a cylindrical glass container having a height of 18 cm and an internal volume of 50 mL for 1 hour, the compatibility was measured visually and evaluated according to the following criteria.

A: No significant turbidity was observed visually. ○: Although it was slightly cloudy, it was almost transparent. X: There was turbidity, and the difference in shading could be discriminated on the top and bottom of the container.
(3) Color difference (Δb)
The thermosetting resin composition was cured to produce a cured product having a thickness of 3 mm. The produced cured product was stored at 150 ° C. for 24 hours, and then the color difference (Δb) of the cured product was measured with a color difference meter [manufactured by Minolta Co., Ltd., CM-3500d]. When the value of the measured color difference (Δb) was 2 or less, it was judged to be suitable for practical use from the viewpoint of colorless transparency.
(4) Hardness In accordance with the Shore A hardness method in JIS K6253: 2006 “Vulcanized rubber and thermoplastic rubber-Determination of hardness”, using a type A durometer, the needle height is 2.50 mm and the spring load is 550 mN. The measurement was performed.
[Examples 1 to 8, preparation of thermosetting resin composition]
Thermosetting resin by stirring and mixing the polysiloxane derivative of component (A), the alicyclic epoxy group-containing cage-type silsesquioxane of component (B) and the polysiloxane having a carboxyl group with the composition shown in Table 2. A composition was prepared.
[Comparative Examples 1-8, Preparation of Thermosetting Resin Composition]
The thermosetting resin composition was prepared by stirring and mixing the component (B) alicyclic epoxy group-containing cage-type silsesquioxane and the polysiloxane having a carboxyl group with the composition shown in Table 3.

  Next, the thermosetting resin compositions of Examples 1 to 8 and Comparative Examples 1 to 8 were molded into a shape matched to the test method described above and subjected to vacuum degassing for 1 minute, and then at 100 ° C for 1 hour After pre-baking, a cured product was obtained by main curing at 150 ° C. for 1 hour.

And about a thermosetting resin composition and hardened | cured material, the viscosity, compatibility, a color difference, and hardness were measured by the above-mentioned method, and those results were shown in Table 2 and Table 3.
In addition, the meaning of the symbol in Table 2 and Table 3 is as follows.

AO-50: Stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, antioxidant (“ADEKA STAB AO-50”, trade name, manufactured by ADEKA Corporation)
X-22-3710: One-terminal carboxylic acid-modified silicone oil [trade name, manufactured by Shin-Etsu Chemical Co., Ltd.], carboxyl equivalent 1,470 g / mol
X-22-169AS: Alicyclic epoxy-modified silicone oil [trade name, manufactured by Shin-Etsu Chemical Co., Ltd.], epoxy equivalent 500 g / mol

表２に示したように、実施例１〜８の熱硬化性樹脂組成物では、粘度、相溶性、色差及び硬度のいずれの物性についても優れることが明らかになった。従って、実施例１〜８の熱硬化性樹脂組成物は光半導体用封止剤などの光学電子部材として好適に使用することができることが実証された。

As shown in Table 2, it was revealed that the thermosetting resin compositions of Examples 1 to 8 were excellent in all physical properties of viscosity, compatibility, color difference and hardness. Therefore, it was demonstrated that the thermosetting resin compositions of Examples 1 to 8 can be suitably used as an optical electronic member such as an optical semiconductor sealing agent.

  On the other hand, as apparent from Comparative Examples 1 and 2, when the blending ratio of the blocked polysiloxane (A) and the alicyclic epoxy group-containing cage silsesquioxane (B) is not within the scope of the present invention. Therefore, good curability cannot be obtained. Further, as is apparent from Comparative Examples 3 and 4, when an epoxy compound different from the alicyclic epoxy group-containing cage silsesquioxane (B) used in the present invention is used, the composition has an apparent compatibility. May be good, but the color difference deteriorates after curing. Alternatively, as is apparent from Comparative Examples 5 to 8, when a curing agent different from the blocked polysiloxane (A) used in the present invention is used, the compatibility is deteriorated and separation occurs. In addition, as in Comparative Example 8, a significant increase in the viscosity was also observed.

Claims (1)

A thermosetting resin composition comprising the following component (A) and component (B), wherein the mass ratio of both components is component (A) / component (B) = 20/80 to 80/20 object.
Component (A): a compound having a plurality of carboxyl groups and having a structure represented by the following formula (1) and having at least 10 mol% of the carboxyl groups in the carboxyl group-containing polysiloxane is represented by the following formula (3): Polysiloxane derivatives blocked by reaction.

In [Equation (1), a is an integer of 0 to 50, b is an integer of 3 to 300, ^{R 1} is an alkyl group having 1 to 6 carbon atoms, ^{X 1} is represented by the following formula (2) X ² is a substituent represented by R ¹ or the following formula (2) (provided that when a = 0, X ² ≠ R ¹ ), and R ¹ and X ¹ are the same or different. May be. ]

Wherein (2), ^{R 2} is an alkylene group or alkylene oxyalkylene group having 1 to 10 carbon atoms, k is 0 or 1. ]

Wherein (3), ^{R 3} is an alkyl group having 1 to 10 carbon atoms. ]
Component (B): an alicyclic epoxy group-containing cage silsesquioxane having a plurality of alicyclic epoxy groups and having a structure represented by the following formula (4).

[In the formula (4), R ⁴ is a group having an alicyclic epoxy group represented by the following formula (5), R ⁵ is a group having an alkoxysilyl group represented by the following formula (6), and R ⁶ is substituted or An unsubstituted alkyl group or hydrogen, r is a number selected from 6, 8, 10, and 12, p is an integer of 2 to r, and q is an integer of 0 to (rp). ]

[In Formula (5), R < ⁷ > is a C1-C10 alkylene group or alkyleneoxyalkylene group. ]

[In Formula (6), R ⁸ is an alkylene group or alkyleneoxyalkylene group having 1 to 10 carbon atoms, R ⁹ is an alkyl group having 1 to 4 carbon atoms, and R ¹⁰ is an alkyl group having 1 to 4 carbon atoms. , M is an integer of 1 to 3. ]