JPWO2014129347A1 - Curable resin composition - Google Patents

Abstract

Provided is a curable resin composition having excellent adhesion, particularly adhesion after a moisture reflow test. The curable resin composition includes a branched organopolysiloxane (A) having an alkenyl group, a linear organopolysiloxane (B) having at least two silicon-bonded hydrogen atoms in one molecule, A block copolymer (C) containing a siloxane block (c1) and a hydrocarbon polymer block (c2), and a hydrosilylation catalyst (D) are contained.

Description

  The present invention relates to a curable resin composition.

Conventionally, a curable resin composition containing a silicone resin is known, and is used as, for example, a composition for optical semiconductor sealing.
For example, in [Claim 1] of Patent Document 1, “(A) a branched chain having at least 3 alkenyl groups in one molecule and at least 30 mol% of all silicon-bonded organic groups is an aryl group”. Organopolysiloxane, (B) linear organopolysiloxane having both ends of the molecular chain blocked with diorganohydrogensiloxy groups and having an aryl group, (C) at least 3 diorganohydrogens in one molecule A curable organopolysiloxane composition comprising a branched organopolysiloxane having a siloxy group and at least 15 mol% of all silicon-bonded organic groups being an aryl group, and (D) a catalyst for hydrosilylation reaction. Is described.

JP 2010-1336 A

In recent years, the level of performance required for a curable resin composition containing a silicone resin has increased, and for example, better adhesion to an adherend has been demanded.
In particular, even when a reflow test (humidity reflow test) is performed after being left in a high humidity environment for a long time, it is required to exhibit excellent adhesion.

  This invention is made | formed in view of the above point, and it aims at providing the curable resin composition which is excellent in adhesiveness, especially the adhesiveness after a moisture-proof reflow test.

  As a result of intensive studies to achieve the above object, the present inventors have found that the adhesion after the moisture-resistant reflow test is improved by adding a specific block copolymer to the curable resin composition. Completed the invention.

That is, the present invention provides the following (I) to (V).
(I) a branched organopolysiloxane (A) having an alkenyl group, a linear organopolysiloxane (B) having at least two silicon-bonded hydrogen atoms in one molecule, and a polysiloxane block (c1) A curable resin composition containing a block copolymer (C) containing a hydrocarbon polymer block (c2) and a hydrosilylation catalyst (D).
(II) The curable resin composition according to (I), wherein the hydrocarbon polymer block (c2) includes a (meth) acrylic polymer block and / or an isobutylene polymer block.
(III) In the block copolymer (C), the mass ratio (c1 / c2) of the polysiloxane block (c1) to the hydrocarbon polymer block (c2) is 20/80 to 80/20. The curable resin composition as described in (I) or (II).
(IV) The curable resin composition according to any one of (I) to (III), wherein the branched organopolysiloxane (A) is an organopolysiloxane represented by the following average unit formula (1): object.
(R ¹ SiO _3/2 ) _a (R ¹ ₂ SiO _2/2 ) _b (R ¹ ₃ SiO _1/2 ) _c (SiO _4/2 ) _d (X ¹ O _1/2 ) _e (1)
(In Formula (1), each R ¹ is independently a substituted or unsubstituted monovalent hydrocarbon group. However, in one molecule, at least one of R ¹ is an alkenyl group, and at least one of R ¹ is Each is an aryl group.
In formula (1), X ¹ is a hydrogen atom or an alkyl group.
In formula (1), a is a positive number, b is 0 or a positive number, c is 0 or a positive number, d is 0 or a positive number, e is 0 or a positive number, and , B / a is a number in the range of 0-10, c / a is a number in the range of 0-5, d / (a + b + c + d) is a number in the range of 0-0.3, e / (a + b + c + d) is a number in the range of 0 to 0.4. )
(V) The curable resin composition according to any one of (I) to (IV), which is a composition for encapsulating an optical semiconductor element.

  ADVANTAGE OF THE INVENTION According to this invention, the curable resin composition which is excellent in adhesiveness, especially the adhesiveness after a moisture-resistant reflow test can be provided.

The curable resin composition of the present invention (hereinafter also referred to as “the composition of the present invention”) includes a branched organopolysiloxane (A) having an alkenyl group and at least two silicon-bonded hydrogen atoms in one molecule. A linear organopolysiloxane having an atom (B), a block copolymer (C) comprising a polysiloxane block (c1) and a hydrocarbon polymer block (c2), a hydrosilylation catalyst (D), Is a curable resin composition.
Hereinafter, each component contained in the composition of the present invention will be described in detail.

<Branched organopolysiloxane (A)>
The branched organopolysiloxane (A) is a branched organopolysiloxane having an alkenyl group.
Examples of the alkenyl group include alkenyl groups having 2 to 18 carbon atoms such as vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, octenyl group, etc., and vinyl group (hereinafter referred to as “Vi”). Is preferred).
2-12 mass% is preferable and, as for the alkenyl group in 1 molecule, 3-10 mass% is more preferable.

The branched organopolysiloxane (A) preferably has at least one aryl group, more preferably at least 30 mol% of all silicon-bonded organic groups are aryl groups, and at least 40 mol% is aryl. More preferably, it is a group.
Examples of the aryl group include aryl groups having 6 to 18 carbon atoms such as a phenyl group, a tolyl group, and a xylyl group, and a phenyl group is preferable.
As a result, the resulting cured product is less attenuated by light refraction, reflection, scattering and the like, and when the linear organopolysiloxane (B) described later has an aryl group, Excellent compatibility with siloxane (B), turbidity and the like are suppressed, and the transparency of the cured product is excellent.

  Examples of the group bonded to the other silicon atom in the branched organopolysiloxane (A) include substituted or unsubstituted monovalent hydrocarbon groups excluding alkenyl groups and aryl groups. Specifically, For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, various pentyl groups, various hexyl groups, various octyl groups, various decyl groups, An alkyl group having 1 to 18 carbon atoms such as a cyclopentyl group and a cyclohexyl group; an aralkyl group having 7 to 18 carbon atoms such as a benzyl group and a phenethyl group; a 3-chloropropyl group and a 3,3,3-trifluoropropyl group; C1-C18 halogenated alkyl group; etc., and other small amounts of groups include silicon atom-bonded hydroxy groups and silicon atom bonds. It may have an alkoxy group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

Such a branched organopolysiloxane (A) is preferably an organopolysiloxane represented by the following average unit formula (1).
(R ¹ SiO _3/2 ) _a (R ¹ ₂ SiO _2/2 ) _b (R ¹ ₃ SiO _1/2 ) _c (SiO _4/2 ) _d (X ¹ O _1/2 ) _e (1)

In formula (1), each R ¹ is independently a substituted or unsubstituted monovalent hydrocarbon group. Examples of the monovalent hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, various pentyl groups, and various hexyl groups. Alkyl groups having 1 to 18 carbon atoms such as various octyl groups, various decyl groups, cyclopentyl groups, and cyclohexyl groups; those having 2 to 18 carbon atoms such as vinyl groups, allyl groups, butenyl groups, pentenyl groups, hexenyl groups, and octenyl groups. Alkenyl group; aryl group having 6 to 18 carbon atoms such as phenyl group, tolyl group and xylyl group; aralkyl group having 7 to 18 carbon atoms such as benzyl group and phenethyl group; 3-chloropropyl group, 3,3,3- C1-C18 halogenated alkyl groups, such as a trifluoropropyl group;
However, in one molecule, at least one of R ¹ is an alkenyl group, and the amount of R ¹ that is an alkenyl group is preferably 2 to 12% by mass, and more preferably 3 to 10% by mass.
In addition, in one molecule, at least one R ¹ is preferably an aryl group, more preferably at least 30 mol% of all R ¹ is an aryl group, and at least 40 mol% is an aryl group. Further preferred.

In formula (1), X ¹ is a hydrogen atom or an alkyl group. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, various pentyl groups, various hexyl groups, and various octyl groups. Groups, various decyl groups, cyclopentyl groups, cyclohexyl groups and the like, and alkyl groups having 1 to 18 carbon atoms are preferable, and a methyl group is preferable.

  In formula (1), a is a positive number, b is 0 or a positive number, c is 0 or a positive number, d is 0 or a positive number, e is 0 or a positive number, and , B / a is a number in the range of 0-10, c / a is a number in the range of 0-5, d / (a + b + c + d) is a number in the range of 0-0.3, e / (a + b + c + d) is a number in the range of 0 to 0.4.

The weight average molecular weight (Mw) of the branched organopolysiloxane (A) is preferably 1,000 to 300,000, and more preferably 2,000 to 100,000.
In this invention, a weight average molecular weight shall be the weight average molecular weight of polystyrene conversion by the gel permeation chromatography (GPC) which uses chloroform as a solvent.
Note that the branched organopolysiloxane (A) is a very viscous semi-solid or solid material, and it is difficult to measure the viscosity.

<Linear organopolysiloxane (B)>
The linear organopolysiloxane (B) is an organopolysiloxane having at least two silicon-bonded hydrogen atoms in one molecule. If linear organopolysiloxane (B) is mainly linear, it may have a small amount (for example, less than 2 mol% of all siloxane units) of a branch.

  The linear organopolysiloxane (B) undergoes an addition reaction (hydrosilylation reaction) with respect to the alkenyl group of the branched organopolysiloxane (A) described above. At this time, since the straight-chain organopolysiloxane (B) has at least two silicon-bonded hydrogen atoms (Si—H), it functions as a cross-linking agent between the branched-chain organopolysiloxane (A). Can do.

  The degree of polymerization of the linear organopolysiloxane (B) is preferably more than 10, more preferably more than 30, more preferably more than 30 and not more than 1,000, and particularly preferably more than 30 and not more than 500. Thereby, the composition of this invention is more excellent in adhesiveness. This is presumably because toughness occurs in the cured product by containing a polymer component. Also, workability is improved.

The linear organopolysiloxane (B) preferably has at least one aryl group because the resulting cured product is less attenuated by light refraction, reflection, scattering, etc. More preferably, at least 30 mol% is an aryl group, and at least 40 mol% is more preferably an aryl group.
Examples of the aryl group include aryl groups having 6 to 18 carbon atoms such as a phenyl group, a tolyl group, and a xylyl group, and a phenyl group is preferable.

  Examples of the group bonded to the silicon atom in the linear organopolysiloxane (B) include a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated group. Specifically, For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, various pentyl groups, various hexyl groups, various octyl groups, various decyl groups, C1-C18 alkyl groups such as cyclopentyl and cyclohexyl groups; C6-C18 aryl groups such as phenyl, tolyl and xylyl groups; C7-C18 aralkyl groups such as benzyl and phenethyl groups A halogenated alkyl group having 1 to 18 carbon atoms such as a 3-chloropropyl group or a 3,3,3-trifluoropropyl group;

Such a linear organopolysiloxane (B) is preferably a linear organopolysiloxane having both ends of the molecular chain blocked with diorganohydrogensiloxy groups. For example, in the following formula (2) The organopolysiloxane represented is mentioned.
HR ² ₂ SiO (R ² ₂ SiO) _n SiR ² ₂ H (2)

In the formula (2), each R ² is independently a substituted or unsubstituted monovalent hydrocarbon group having no aliphatic unsaturated bond. Examples of the monovalent hydrocarbon group for R ² include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, various pentyl groups, and various types. C1-C18 alkyl groups such as hexyl group, various octyl groups, various decyl groups, cyclopentyl group, cyclohexyl group; aryl groups having 6-18 carbon atoms such as phenyl group, tolyl group, xylyl group; benzyl group, phenethyl Aralkyl groups having 7 to 18 carbon atoms such as groups; halogenated alkyl groups having 1 to 18 carbon atoms such as 3-chloropropyl groups and 3,3,3-trifluoropropyl groups; It is preferably an alkyl group of 1 to 18 and more preferably a methyl group (hereinafter sometimes referred to as “Me”).
Note that at least one of R ² is preferably an aryl group, more preferably at least 30 mol% is an aryl group, and even more preferably at least 40 mol% is an aryl group. The aryl group is an aryl group having 6 to 18 carbon atoms, and is preferably a phenyl group (hereinafter sometimes referred to as “Ph”).

  In the formula (2), n is an integer of 1 or more, preferably an integer of more than 10, more preferably an integer of more than 30, more preferably an integer of more than 30 and less than 1,000, and particularly preferably an integer of more than 30 and less than 500 preferable. If n is the said range, adhesiveness will be more excellent.

The weight average molecular weight (Mw) of the linear organopolysiloxane (B) is preferably 500 to 1,000,000, and more preferably 1,000 to 30,000, because toughness occurs in the cured product.
The viscosity of the linear organopolysiloxane (B) at 25 ° C. is preferably 20 to 1,000,000 mPa · s, more preferably 200 to 100,000 mPa · s.
In the present invention, the viscosity is measured at 25 ° C. in accordance with 4.1 (Brookfield rotary viscometer) of JIS K7117-1.

(Production method of linear organopolysiloxane (B))
The production method of the linear organopolysiloxane (B) is not particularly limited. For example, an organopolysiloxane (b1) having two or more silanol groups in one molecule and a hydrogen atom bonded to a silicon atom. The above-mentioned polysiloxane (B) main product is produced by reacting with disiloxane (b2) having water (H ₂ O) as a by-product and optionally dehydrating and condensing silanol groups remaining by the reaction. The method obtained as a thing is mentioned.

At this time, for example, the reaction is traced by ¹ H-NMR to confirm the disappearance of the peak derived from the silanol group of the organopolysiloxane (b1) or the appearance of the peak derived from a component other than the component used in the reaction. By doing this, the reaction can be completed as a reaction product containing the linear organopolysiloxane (B), which is the main product, and by-products.

Examples of the organopolysiloxane (b1) used in the above reaction include organopolysiloxanes represented by the following formula (3). Examples of the disiloxane (b2) include those represented by the following formula (4). The disiloxane represented is mentioned.
HO (R ² ₂ SiO) _m H (3)
HR ² ₂ SiOSiR ² ₂ H (4)
In formula (3) and formula (4), R ² has the same meaning as R ² described above. Moreover, in Formula (3), m is an integer below n mentioned above.

In the above production method, for example, a part of the silanol group of the organopolysiloxane (b1) of the formula (3) is blocked with -SiR ² ₂ H derived from the disiloxane (b2) of the formula (4), and the rest It is polymerized by condensing the silanol group. For this reason, the degree of polymerization of the linear organopolysiloxane (B) depends on the amount of disiloxane (b2) charged.

The blending ratio of each component in the above reaction is preferably such that the disiloxane (b2) is 0.001 to 0.2 mol with respect to 10 mol of silanol groups in the organopolysiloxane (b1).
The above reaction is preferably carried out by stirring. In stirring, it is preferable to heat in a temperature range of 50 to 65 ° C., for example, and the stirring time (reaction time) is preferably 1 to 5 hours, for example.

  20-60 mass parts is preferable with respect to 100 mass parts of branched organopolysiloxane (A) mentioned above, and, as for content of linear organopolysiloxane (B), 30-50 mass parts is more preferable. If content of linear organopolysiloxane (B) is this range, the sclerosis | hardenability of the composition of this invention is excellent, and adhesiveness is also more excellent.

<Block copolymer (C)>
The block copolymer (C) contained in the composition of the present invention is a block copolymer (block copolymer) containing a polysiloxane block (c1) and a hydrocarbon polymer block (c2).

Such a block copolymer (C) includes, for example, a polysiloxane (c1 ′) having a terminal reactive group and a hydrocarbon polymer (c2 ′) having a terminal group capable of reacting with the terminal reactive group. It is obtained by forming a copolymer chain containing a polysiloxane block (c1) and a hydrocarbon-based polymer block (c2) by reacting under conditions where the reaction between the terminal reactive group and the terminal group proceeds. .
As a method for obtaining the block copolymer (C), for example, a polysiloxane (c1 ′) in which the terminal reactive group is a silicon atom-bonded hydrogen atom (Si—H) and a hydrocarbon heavy polymer in which the terminal group is an alkenyl group. A method in which the compound (c2 ′) is hydrosilylated using a hydrosilylation reaction catalyst; the polysiloxane (c1 ′) in which the terminal reactive group is an alkenyl group; and the terminal group is a silicon-bonded hydrogen atom ( A method in which a hydrocarbon polymer (c2 ′) which is Si—H) is similarly hydrosilylated; and the like. At this time, the hydrosilylation reaction catalyst (D) described later can be used as the hydrosilylation reaction catalyst.

The composition of the present invention contains such a block copolymer (C) in combination with the above-mentioned branched organopolysiloxane (A) and linear organopolysiloxane (B). In particular, the adhesiveness after the moisture-resistant reflow test is excellent. The reason is considered as follows.
First, since the block copolymer (C) contains the polysiloxane block (c1), it has high compatibility with the above-mentioned branched organopolysiloxane (A) and linear organopolysiloxane (B), It is considered to be incorporated.
The block copolymer (C) includes a hydrocarbon polymer block (c2) such as an isobutylene polymer block or a (meth) acrylic polymer block. These hydrocarbon polymer blocks (c2) Since the main chain consists of hydrocarbon chains and the side chains may have many hydrocarbon groups, the moisture resistance is relatively high (low water vapor permeability) compared to polysiloxane. It is considered that the cured product of the composition of the invention suppresses the intrusion of moisture even in a high humidity environment and improves the adhesion after the moisture reflow test.
On the other hand, when the composition of the present invention contains, for example, mere polyisobutylene that is not block copolymerized, instead of the block copolymer (C), this polymer is a branched organopolysiloxane (A ) And the linear organopolysiloxane (B) are not incorporated and become an isolated state, so that the effect of suppressing the intrusion of moisture into the cured product is reduced. Moreover, since this polymer is not compatible with the branched organopolysiloxane (A) and the linear organopolysiloxane (B), which are silicones, the cured product becomes turbid and inferior in transparency.

(Polysiloxane block (c1))
The polysiloxane block (c1) contained in the block copolymer (C) has a polysiloxane structure composed of a plurality of siloxane units. In addition, if the polysiloxane block (c1) is mainly linear, it may have a small amount (for example, less than 2 mol% of all siloxane units) of branches.

As described above, the polysiloxane block (c1) is derived from, for example, the polysiloxane (c1 ′) having a terminal reactive group. Examples of the terminal reactive group possessed by the polysiloxane (c1 ′) include silicon atom-bonded hydrogen atoms (Si—H); 2 carbon atoms such as vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, and octenyl group. -18 alkenyl groups; and the like.
As such a polysiloxane (c1 ′), for example, a polysiloxane represented by the following formula (5) is preferably exemplified.
R ³² R ³¹ ₂ SiO (R ³¹ ₂ SiO) _k SiR ³¹ ₂ R ³² (5)

In formula (5), R ³¹ is independently a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group. Examples of the monovalent hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, various pentyl groups, and various hexyl groups. Alkyl groups having 1 to 18 carbon atoms such as various octyl groups, various decyl groups, cyclopentyl groups, and cyclohexyl groups; those having 2 to 18 carbon atoms such as vinyl groups, allyl groups, butenyl groups, pentenyl groups, hexenyl groups, and octenyl groups. Alkenyl group; aryl group having 6 to 18 carbon atoms such as phenyl group, tolyl group and xylyl group; aralkyl group having 7 to 18 carbon atoms such as benzyl group and phenethyl group; 3-chloropropyl group, 3,3,3- A halogenated alkyl group having 1 to 18 carbon atoms such as a trifluoropropyl group; among others, an alkyl group having 1 to 18 carbon atoms, Preferably an aryl group prime 6-18, a methyl group, a phenyl group is more preferable.
R ³¹ may be a hydrogen atom or an alkenyl group. In that case, 2 to 4 R ³¹ are preferably a hydrogen atom or an alkenyl group in one molecule, and 2 to 3 R ³¹ are A hydrogen atom or an alkenyl group is more preferable.

In formula (5), R ³² is independently the above-mentioned terminal reactive group, specifically, for example, hydrogen atom; carbon number such as vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, octenyl group, etc. 2-18 alkenyl groups; and the like.

In the formula (5), k is an integer of 1 or more, preferably 1 to 1,000, and can be a numerical value corresponding to the weight average molecular weight of the polysiloxane (c1 ′).
The weight average molecular weight of the polysiloxane (c1 ′) is preferably from 100 to 100,000, more preferably from 500 to 50,000, from the viewpoints of elongation characteristics and transparency.

(Hydrocarbon polymer block (c2))
The hydrocarbon polymer block (c2) contained in the block copolymer (C) has a structure composed of a hydrocarbon polymer, and contributes to improvement of moisture resistance.
Examples of such a hydrocarbon polymer block (c2) include an isobutylene polymer block, a (meth) acrylic polymer block, and a hydrogenated polybutadiene block.
Of these, the isobutylene polymer block and / or the (meth) acrylic polymer block are preferred because they have better moisture resistance and better adhesion after the moisture reflow test in the composition of the present invention. An isobutylene polymer block is more preferable.

Such a hydrocarbon-based polymer block (c2) is derived from, for example, the hydrocarbon-based polymer (c2 ′) having the above end groups as described above.
Examples of the terminal group of the hydrocarbon polymer (c2 ′) include silicon atom-bonded hydrogen atoms (Si—H); carbon such as vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, and octenyl group. Alkenyl groups of 2 to 18; and the like. Among them, vinyl group and allyl group are preferable.
Examples of such a hydrocarbon polymer (c2 ′) include a (meth) acrylic polymer having the terminal group, an isobutylene polymer having the terminal group, and the like.
The weight average molecular weight of the hydrocarbon polymer (c2 ′) is preferably 1,000 to 100,000, and more preferably 2,000 to 50,000, because the moisture resistance is more excellent.

As the (meth) acrylic polymer having the terminal group, those in which the main chain is mainly polymerized from a (meth) acrylic monomer are preferable. Here, “mainly” means that 50 mol% or more of the monomer units constituting the main chain is the above monomer, and preferably 70 mol% or more.
As said (meth) acrylic-type monomer, a (meth) acrylic acid monomer, a (meth) acrylic acid ester monomer, etc. are mentioned, for example, (meth) acrylic acid ester monomer is preferable.
Specific examples of the (meth) acrylate monomer include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, and butyl (meth) acrylate.
In the present invention, the (meth) acrylic acid ester monomer may be copolymerized with other monomers, and further block copolymerized. In this case, the (meth) acrylic acid ester monomer is 40% by mass. It is preferable that it is contained above.
In addition, the coupling | bonding form of the said end group and the principal chain of a (meth) acrylic-type polymer is not specifically limited, For example, carbon-carbon bond, ester bond, ether bond, carbonate bond, amide bond, urethane bond etc. A combined form is mentioned.

In the isobutylene polymer having an end group, the “isobutylene polymer” is not limited to those in which all of the monomer units are formed from isobutylene units, and is a monomer having a copolymerizability with isobutylene. In an isobutylene polymer. Examples of such monomer components include olefins having 4 to 12 carbon atoms, vinyl ethers, aromatic vinyl compounds, vinyl silanes, allyl silanes, and the like.
However, the monomer copolymerizable with isobutylene is preferably 50% by mass or less, more preferably 30% by mass or less, further preferably 20% by mass or less, and all of the monomer units are formed from isobutylene units. It is particularly preferred that
As the isobutylene polymer having such a terminal group, for example, diallyl-terminated polyisobutylene represented by the following formula (6) is preferably exemplified. In the following formula (6), PIB represents polyisobutylene.
_{CH 2 = CHCH 2 -PIB-CH} 2 CH = CH 2 ··· (6)

In the present invention, for example, polysiloxane (c1 ′) represented by the above formula (5) and R ³² represents a hydrogen atom or an alkenyl group, and a hydrocarbon which is an isobutylene polymer represented by the formula (6) The block copolymer (C) containing the polysiloxane block (c1) and the hydrocarbon polymer block (c2) composed of polyisobutylene can be obtained by proceeding the polymerization with the polymer (c2 ′).

  In the block copolymer (C), the mass ratio (c1 / c2) between the polysiloxane block (c1) and the hydrocarbon polymer block (c2) is such that the polysiloxane block (c1) and the hydrocarbon polymer block (c2). 20/80 to 80/20 are preferable, and 35/65 to 65/35 are more preferable, because the balance with the above is excellent and the adhesion after the moisture-resistant reflow test becomes better.

  The content of the block copolymer (C) is 100 parts by mass in total of the above-mentioned branched organopolysiloxane (A) and linear organopolysiloxane (B) because the adhesion after the moisture reflow test is more excellent. 1 to 50 parts by mass is preferable, 3 to 30 parts by mass is more preferable, and 10 to 25 parts by mass is more preferable.

<Hydrosilylation catalyst (D)>
The hydrosilylation reaction catalyst (D) contained in the composition of the present invention is used in combination with a linear organopolysiloxane (B) having a silicon atom-bonded hydrogen atom to form a branched organopolysiloxane (A). It functions as a catalyst for promoting an addition reaction (hydrosilylation reaction) to an alkenyl group.
At this time, when the block copolymer (C) has a silicon atom-bonded hydrogen atom or an alkenyl group, the reaction also proceeds for these groups by the hydrosilylation reaction catalyst (D).

As the hydrosilylation catalyst (D), a conventionally known catalyst can be used, and examples thereof include a platinum-based catalyst, a rhodium-based catalyst, a palladium-based catalyst, and the like, and a platinum-based catalyst is preferable. Specific examples of platinum-based catalysts include chloroplatinic acid, chloroplatinic acid-olefin complexes, chloroplatinic acid-divinyltetramethyldisiloxane complexes, chloroplatinic acid-alcohol coordination compounds, platinum diketone complexes, and the like. May be used alone or in combination of two or more.
The content of the hydrosilylation reaction catalyst (D) is a catalytic amount, but because of the excellent curability of the composition of the present invention, the aforementioned branched organopolysiloxane (A) and linear organopolysiloxane described above are used. 0.00001-0.1 mass part is preferable with respect to a total of 100 mass parts of siloxane (B), and 0.0001-0.01 mass part is more preferable.

<Curing retarder (E)>
The composition of the present invention may further contain a curing retarder (E). The curing retarder (E) is a component for adjusting the curing rate and working life of the composition of the present invention.
Specific examples of the curing retarder (E) include 3-methyl-1-butyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, phenylbutynol, 1-ethynyl- Alcohol derivatives having a carbon-carbon triple bond such as 1-cyclohexanol; enyne compounds such as 3-methyl-3-penten-1-yne and 3,5-dimethyl-3-hexen-1-yne; tetramethyltetravinyl Alkenyl group-containing low molecular weight siloxane such as cyclotetrasiloxane and tetramethyltetrahexenylcyclotetrasiloxane; methyl-tris (3-methyl-1-butyne-3-oxy) silane, vinyl-tris (3-methyl-1-butyne- Alkyne-containing silanes such as 3-oxy) silane; and the like may be used alone or in combination of two or more. It may be used in combination.
The content of the curing retarder (E) is appropriately selected according to the method of using the composition of the present invention, and for example, the above-described branched organopolysiloxane (A) and linear organopolysiloxane ( 0.00001-0.1 mass part is preferable with respect to a total of 100 mass parts of B), and 0.0001-0.01 mass part is more preferable.

<Adhesion imparting agent (F)>
The composition of the present invention may further contain an adhesion promoter (F).
Examples of the adhesion-imparting agent (F) include a silane coupling agent. Specific examples of the silane coupling agent include amino silane, vinyl silane, epoxy silane, methacryl silane, isocyanate silane, imino silane, reaction products thereof, compounds obtained by reaction of these with polyisocyanate, and the like, which are epoxy silanes. Is preferred.
The epoxy silane is not particularly limited as long as it is a compound having an epoxy group and an alkoxysilyl group. Specific examples thereof include γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylethyldiethoxysilane, Dialkoxyepoxysilanes such as γ-glycidoxypropylmethyldiethoxysilane, β- (3,4 epoxycyclohexyl) ethylmethyldimethoxysilane; γ-glycidoxypropyltrimethoxysilane, β- (3,4 epoxycyclohexyl) Trialkoxy epoxy silanes such as ethyltrimethoxysilane; and the like.

  Further, the adhesion-imparting agent (F) may be, for example, a dehydration condensate of the above epoxy silane. Specifically, for example, γ-glycidoxypropyltrimethoxysilane, phenyltrimethoxysilane, 1 , 3-divinyl-1,1,3,3-tetramethyldisiloxane and the dehydration condensation product of epoxy silane.

  The content of the adhesion-imparting agent (F) is not particularly limited, but is 0.5 to about 100 parts by mass of the total of the above-described branched organopolysiloxane (A) and linear organopolysiloxane (B). 10 mass parts is preferable and 1-5 mass parts is more preferable.

The manufacturing method of the composition of this invention is not specifically limited, For example, the method of manufacturing by mixing the essential component mentioned above and an arbitrary component is mentioned.
Moreover, the method of hardening the composition of this invention and obtaining hardened | cured material is not specifically limited, For example, the method of heating the composition of this invention at 80-200 degreeC for 10-720 minutes is mentioned.

  The composition of the present invention is, for example, in the field of display materials, optical recording medium materials, optical equipment materials, optical component materials, optical fiber materials, optical / electronic functional organic materials, semiconductor integrated circuit peripheral materials, etc. It can be used as a primer, a sealing material and the like.

In particular, the composition of the present invention can be suitably used as a composition for encapsulating an optical semiconductor because it has excellent adhesion and its cured product exhibits good transparency and high refractive index.
The optical semiconductor to which the composition of the present invention can be applied is not particularly limited, and examples thereof include a light emitting diode (LED), an organic electroluminescent element (organic EL), a laser diode, and an LED array.
As a method for using the composition of the present invention as an optical semiconductor sealing composition, for example, the composition of the present invention is applied to an optical semiconductor, and the optical semiconductor to which the composition of the present invention is applied is heated. The method of hardening the composition of invention is mentioned.
At this time, the method for applying and curing the composition of the present invention is not particularly limited, and examples thereof include a method using a dispenser, a potting method, screen printing, transfer molding, and injection molding.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

<Production of Si-Vi-based branched organopolysiloxane 1>
In a four-necked flask equipped with a stirrer, reflux condenser, inlet and thermometer, 21.4 g of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 60 g of water, 0.14 g of trifluoromethanesulfonic acid Then, 200 g of toluene was added and mixed, and 151.5 g of phenyltrimethoxysilane was added dropwise over 1 hour while stirring. After completion of the addition, the mixture was heated to reflux for 1 hour. After cooling, the lower layer was separated, and the toluene solution layer was washed with water three times. 100 g of 5% aqueous sodium hydrogen carbonate solution was added to the toluene solution layer that had been washed with water, and the mixture was heated to 75 ° C. with stirring and refluxed for 1 hour. After cooling, the lower layer was separated, and the upper toluene solution layer was washed with water three times. The remaining toluene solution layer was concentrated under reduced pressure, and was represented by the following average unit formula (7) that was semi-solid at 25 ° C. Methylphenylvinylpolyethylene having an average vinyl group content in one molecule of 3.6% by mass. A branched organopolysiloxane 1 which is a siloxane resin was obtained.
(ViMe ₂ SiO _1/2 ) _0.25 (Ph ₂ SiO _3/2 ) _0.75 (7)

<Production of Si-H-based linear organopolysiloxane 1>
In a flask equipped with a stirrer and a reflux condenser, 100 g of linear organopolysiloxane having a silanol group represented by the following formula (8), 1.5 g of 1,1,3,3-tetramethyldisiloxane and trifluoromethane 0.1 g of sulfonic acid was added, stirred and heated at 50 ° C. for 2 hours. Thereafter, 150 g of toluene was added, and the generated water was discharged out of the system. The toluene layer was washed with water three times and then concentrated under reduced pressure to obtain a linear organopolysiloxane 1 represented by the following formula (9).
HO (Ph ₂ SiO) ₃ (Me ₂ SiO) ₃ H (8)
HMe ₂ SiO (Ph ₂ SiO) ₃₀ (Me ₂ SiO) ₃₀ SiMe ₂ H (9)

<Production of block copolymer 1>
100 parts by mass of dimethylsiloxane / diphenylsiloxane copolymer having a dimethylhydrogensiloxy group blocked at both molecular chains (weight average molecular weight: 12,000) and 50 parts by mass of diallyl-terminated polyisobutylene (weight average molecular weight: 12,000) A block copolymer 1 containing a polysiloxane block and a polyisobutylene block is obtained by using 0.001 part by mass of the hydrosilylation reaction catalyst 1 described later at 70 ° C. for 4 hours to proceed with the hydrosilylation reaction. Obtained.
The mass ratio (c1 / c2) of the obtained block copolymer 1 was 50/50.

[Examples 1 to 4, Standard Example 1, Comparative Example 1]
<Manufacture of curable resin composition>
The components shown in Table 1 below were used in the amounts shown in the table (unit: parts by mass), and these were uniformly mixed with a vacuum stirrer to give a curable resin composition (hereinafter also simply referred to as “composition”). Manufactured.

<Transmissivity>
The produced composition was cured by heating at 150 ° C. for 2 hours to obtain a cured product (thickness = 2.0 mm). About the obtained hardened | cured material, according to JISK0115: 2004, the transmittance | permeability (unit:%) in wavelength 400nm was measured using the ultraviolet-visible (UV-Vis) absorption-spectrum measuring apparatus (made by Shimadzu Corp.). The measurement results are shown in Table 1 below. If the transmittance value is 80% or more, it can be evaluated as having excellent “transparency”.

<CF>
The prepared composition was bonded to an adherend (aluminum alloy plate, A1050P, manufactured by Partec Co., Ltd.) with an adhesion area of 12.5 mm × 25 mm, and then cured by heating at 150 ° C. for 2 hours, and tested. Got the body. Using the obtained test body, a tensile test was performed in accordance with JIS K6850: 1999, and the ratio (unit:%) of the cohesive failure (CF) area to the adhesion area was measured. The results are shown in Table 1 below. The closer the value of CF is to 100, the better the adhesion.

<Peeling evaluation>
The manufactured composition was applied to an LED package (manufactured by Enomoto) and cured by heating at 150 ° C. for 2 hours to prepare a plurality of test bodies for each example. Next, for each of the following three types of tests, eight test bodies were provided for each example, and the number of the test bodies in which peeling of the cured product was not confirmed was counted. The larger the number, the better the adhesion.
(Reflow test)
After leaving the test body on a hot plate heated to 280 ° C. for 40 seconds, the presence or absence of peeling of the cured product was visually confirmed.
(Moist heat test)
The specimen was left for 1000 hours in an environment at a temperature of 85 ° C. and a humidity of 85%, and then the presence or absence of peeling of the cured product was visually confirmed.
(Moisture resistance reflow test)
The test specimen was left in an environment of a temperature of 30 ° C. and a humidity of 60% for 192 hours, and then the above reflow test was performed, and the presence or absence of peeling of the cured product was visually confirmed.

The following were used for each component in Table 1.
Branched organopolysiloxane 1: as described above (vinyl content: 5.6% by mass, phenyl group content in all silicon-bonded organic groups: 50 mol%, Mw: 2,500, viscosity : Viscosity could not be measured with very viscous semi-solid material)
Linear organopolysiloxane 1: as described above (content of silicon atom-bonded hydrogen atoms: 0.02% by mass, phenyl group content in all silicon atom-bonded organic groups: 49 mol%, Mw: 5, 000, viscosity: 3,000 mPa · s)
Block copolymer 1: As described above. Polyisobutylene 1: Polymer of isobutylene (weight average molecular weight: 12,000)
Catalyst for hydrosilylation reaction 1: Chloroplatinic acid-divinyltetramethyldisiloxane complex (manufactured by Gelest)
Curing retarder 1: 3-methyl-1-butyn-3-ol (manufactured by Tokyo Chemical Industry Co., Ltd.)
Adhesion imparting agent 1: γ-glycidoxypropyltrimethoxysilane (KBM-403 manufactured by Shin-Etsu Chemical Co., Ltd.), phenyltrimethoxysilane (KBM-103 manufactured by Shin-Etsu Chemical Co., Ltd.), and 1,3-divinyl-1 Epoxysilane dehydration condensate obtained by dehydration condensation with 1,1,3,3-tetramethyldisiloxane

As is apparent from the results shown in Table 1, Examples 1 to 4 using the block copolymer 1 had good peeling evaluation and excellent adhesion, and in particular, the results of the moisture reflow resistance test were good.
On the other hand, the standard example 1 which did not contain the block copolymer 1 was inferior in the results of the moisture reflow test.
Moreover, it turned out that the comparative example 1 using the simple polyisobutylene 1 which is not made into a block copolymer is inferior in transparency because of poor compatibility and inferior in transparency, and has insufficient results in the moisture reflow test.

Claims (5)

A branched organopolysiloxane (A) having an alkenyl group;
A linear organopolysiloxane (B) having at least two silicon-bonded hydrogen atoms in one molecule;
A block copolymer (C) comprising a polysiloxane block (c1) and a hydrocarbon polymer block (c2);
A curable resin composition comprising a hydrosilylation catalyst (D).   The curable resin composition according to claim 1, wherein the hydrocarbon polymer block (c2) includes a (meth) acrylic polymer block and / or an isobutylene polymer block.   In the block copolymer (C), a mass ratio (c1 / c2) between the polysiloxane block (c1) and the hydrocarbon-based polymer block (c2) is 20/80 to 80/20. 2. The curable resin composition according to 2. The curable resin composition according to any one of claims 1 to 3, wherein the branched organopolysiloxane (A) is an organopolysiloxane represented by the following average unit formula (1).
(R ¹ SiO _3/2 ) _a (R ¹ ₂ SiO _2/2 ) _b (R ¹ ₃ SiO _1/2 ) _c (SiO _4/2 ) _d (X ¹ O _1/2 ) _e (1)
(In Formula (1), each R ¹ is independently a substituted or unsubstituted monovalent hydrocarbon group. However, in one molecule, at least one of R ¹ is an alkenyl group, and at least one of R ¹ is Each is an aryl group.
In formula (1), X ¹ is a hydrogen atom or an alkyl group.
In formula (1), a is a positive number, b is 0 or a positive number, c is 0 or a positive number, d is 0 or a positive number, e is 0 or a positive number, and , B / a is a number in the range of 0-10, c / a is a number in the range of 0-5, d / (a + b + c + d) is a number in the range of 0-0.3, e / (a + b + c + d) is a number in the range of 0 to 0.4. )   Curable resin composition in any one of Claims 1-4 which is a composition for optical semiconductor element sealing.