KR102180721B1 - Curable resin composition - Google Patents

Abstract

The present invention makes it a subject to provide a curable resin composition excellent in heat resistance of a cured product. The curable resin composition of the present invention contains a polysiloxane (A) having at least one (meth)acryloyl group per molecule, and a silicone resin (B) represented by a specific average unit formula.

Description

Curable resin composition {CURABLE RESIN COMPOSITION}

The present invention relates to a curable resin composition that can be suitably used as an adhesive for electronic devices such as liquid crystal displays.

In electronic devices such as liquid crystal displays, adhesives are used in various parts. As such an adhesive, a photocurable resin composition containing an acrylic monomer or an acrylic oligomer, etc. are mentioned, for example.

For example, in Patent Document 1, a photo-curable resin composition comprising a (meth)acrylate oligomer (so-called urethane acrylate) having polyurethane in the skeleton as an adhesive for bonding a display body such as a liquid crystal display and an optical functional material Is disclosed (claim 5, etc.).

On the other hand, since electronic devices are often exposed to high temperature environments, heat resistance is required for the adhesive used.

For example, if the heat resistance of an adhesive used in an electronic device is insufficient, the adhesive strength decreases when the electronic device is exposed to a high temperature environment, leading to poor conditions such as malfunction of the electronic device. Therefore, it is required that the adhesive strength of the adhesive used for electronic devices is less likely to decrease even when exposed to a high temperature environment.

In addition, if the heat resistance of the adhesive used in a display device such as a liquid crystal display is insufficient, the cured product of the adhesive deteriorates and becomes colored when exposed to a high temperature environment, and display performance such as visibility is deteriorated. Occurs. Therefore, it is required that no coloration occurs even when exposed to a high-temperature environment for an adhesive used in a display device such as a liquid crystal display.

Patent Document 1: WIPO International Publication No. 2010/027041

The present inventors referred to Patent Document 1 and studied about a curable resin composition containing urethane acrylate, and it was found that when the cured product was exposed to a high temperature environment, a decrease in adhesive strength and coloration occurred. That is, it was found that the heat resistance of the cured product was insufficient.

Therefore, the present invention aims at providing a curable resin composition excellent in heat resistance of a cured product in view of the above circumstances.

The inventors of the present invention have conducted a thorough study to achieve the above problems, and as a result of using a polysiloxane having a (meth)acryloyl group and a silicone resin represented by a specific average unit formula, the cured product has excellent heat resistance. It found that a resin composition was obtained and came to this invention.

That is, the inventors of the present invention have found that the problem can be solved by the following configuration.

(1) A curable resin composition containing a polysiloxane (A) having at least one (meth)acryloyl group in one molecule, and a silicone resin (B) represented by the following average unit formula (1).

^{_{(R 1 SiO 3/2) a (}} R 2 2 SiO 2/2) b (R 3 3 SiO 1/2) c (SiO 4/2) d (X 1 O 1/2) e ... (One)

(In formula (1), R ¹ , R ² and R ³ are each independently selected from the group consisting of an aryl group, a (meth)acryloyl group-containing group, an alkyl group, a cycloalkyl group, a vinyl group-containing group, and an epoxy group-containing group. A plurality of R ² and R ³ may be the same or different, respectively The ratio of the aryl group to all organic groups represented by R ¹ , R ² and R ³ is 25 mol% or more. X ¹ is hydrogen Represents a group selected from the group consisting of an atom and an alkyl group, a, b, c, d and e are,

0<a≤1,

0≤b<1,

0≤c<1,

0≤d<1,

0≤e<1,

0≤b/a≤10,

0≤c/a≤5,

0≤d/(a+b+c+d)≤0.3,

0≤e/(a+b+c+d)≤0.4

Satisfies the relational expression of.)

(2) The curable resin composition according to the above (1), wherein the silicone resin (B) has a (meth)acryloyl group.

(3) The curable resin composition according to (1) or (2), wherein the polysiloxane (A) has an aryl group.

(4) The curable resin composition according to any one of (1) to (3) above, wherein the polysiloxane (A) has an alkoxy group.

(5) The curable resin composition according to any one of (1) to (4) above, wherein the polysiloxane (A) has a urethane bond.

(6) The curable resin composition according to any one of the above (1) to (5), further comprising a monofunctional (meth)acrylic monomer (C) and a photoinitiator.

(7) The curable resin composition according to any one of the above (1) to (6), further comprising a (meth)acrylate monomer (D) having a plurality of ester groups.

As shown below, according to the present invention, a curable resin composition excellent in heat resistance of a cured product can be provided.

Hereinafter, the curable resin composition of the present invention (hereinafter, also referred to simply as the composition of the present invention) will be described. In addition, in this specification, the numerical range shown using "~" means a range including the numerical value described before and after "~" as a lower limit value and an upper limit value.

The composition of the present invention is a curable resin composition containing a polysiloxane (A) having at least one (meth)acryloyl group per molecule, and a silicone resin (B) represented by the average unit formula (1) described later.

It is considered that the composition of the present invention exhibits excellent heat resistance by means of such a constitution.

Although this is not clear in detail, it is estimated to be approximately as follows.

As described above, the composition of the present invention uses a specific polysiloxane (A) and a specific silicone resin (B) in combination. Here, as described later, the silicone resin (B) used in the present invention has a branched structure.

Since the composition of the present invention uses these two components in combination, the cured product becomes a composite of a siloxane skeleton in which a polysiloxane crosslinked with a (meth)acryloyl group and a specific silicone resin having a branched structure are intertwined. Chemical durability such as radicality is improved. It is considered that such improvement in chemical durability contributes to improvement in heat resistance.

This is also estimated from the fact that the heat resistance of the cured product becomes insufficient when the specific polysiloxane (A) and the specific silicone resin (B) are not contained, as shown by Comparative Examples 1 and 2 described later.

In particular, in the present invention, in the silicone resin (B), the aryl group ratio described later is 15 mol% or more. By using such a silicone resin, the packing of aryl groups proceeds during curing, resulting in a cured product that is difficult to change in structure even when exposed to a high temperature environment. That is, it is thought that it becomes a hardened|cured material excellent in heat resistance and toughness.

This is because, as shown in Comparative Example 3 to be described later, even if polysiloxane (A) and a silicone resin are used in combination, when the aryl group ratio of the silicone resin to be described later is less than 15 mol%, the heat resistance of the cured product becomes insufficient. I guess.

Hereinafter, the polysiloxane (A) and the silicone resin (B) and other components that may be contained as desired will be described in detail.

<Polysiloxane (A)>

The polysiloxane (A) used in the composition of the present invention is not particularly limited as long as it is a polysiloxane having at least one (meth)acryloyl group in one molecule. In addition, in this application, the (meth)acryloyl group represents an acryloyl group or a methacryloyl group. In addition, polysiloxane refers to a compound having two or more siloxane structures (-Si-O-) in the main chain.

As described above, the polysiloxane (A) is crosslinked by reaction between the (meth)acryloyl groups of the polysiloxane (A) upon curing. Further, when the silicone resin (B) described later has a (meth)acryloyl group, not only the polysiloxane (A) but also the silicone resin (B) is crosslinked.

Polysiloxane (A) may be a linear polysiloxane or a branched polysiloxane. Especially, it is preferable that it is a linear polysiloxane (linear polysiloxane) from the reason that elongation of a cured product is excellent.

In the polysiloxane (A), the position having the (meth)acryloyl group is not particularly limited. For example, the polysiloxane (A) may have a (meth)acryloyl group at the terminal, or may have a (meth)acryloyl group at the side chain. Among them, it is preferable that the cured product has a (meth)acryloyl group at the terminal from the reason for excellent elongation. When the polysiloxane (A) is a linear polysiloxane, it is preferable to have (meth)acryloyl groups at both ends.

Examples of the group bonded to the silicon atom in the polysiloxane (A) include a hydrogen atom, a halogen atom, a hydroxy group, an alkoxy group, and a hydrocarbon group which may have a hetero atom.

As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, for example.

Examples of the hetero atom of the hydrocarbon group which may have the hetero atom include an oxygen atom, a nitrogen atom, a sulfur atom, and a phosphorus atom.

Examples of the hydrocarbon group of the hydrocarbon group which may have a hetero atom may include an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination thereof.

The aliphatic hydrocarbon group may be linear, branched, or cyclic. Specific examples of the aliphatic hydrocarbon group include a linear or branched alkyl group (especially, 1 to 10 carbon atoms), a linear or branched alkenyl group (2 to 10 carbon atoms), and a linear or branched alkynyl group (especially, C2-C10), a linear or branched cycloalkyl group, etc. are mentioned.

As said aromatic hydrocarbon group, a C6-C20 aromatic hydrocarbon group etc. are mentioned, for example, More specifically, an aryl group, a naphthyl group, etc. are mentioned. Examples of the aryl group include an aryl group having 6 to 18 carbon atoms such as a phenyl group (hereinafter, sometimes represented by ``Ph''), a tolyl group, and a xylyl group, and among them, a phenyl group desirable.

It is preferable that the polysiloxane (A) has an aryl group. Specific examples of the aryl group and suitable embodiments are as described above.

Among these, it is preferable that 5 to 50 mol% of the group bonded to the silicon atom of the polysiloxane (A) is an aryl group, and more preferably 10 to 30 mol% is an aryl group.

It is preferable that polysiloxane (A) has an alkoxy group from the reason excellent in adhesiveness with an adherend.

It is preferable that the polysiloxane (A) has an aryl group and an alkoxy group from the viewpoint of transparency.

It is preferable that the polysiloxane (A) has a urethane bond from the reason that hydrogen bonds are formed in the cured product and the adhesion of the cured product is improved.

As a suitable aspect of the polysiloxane (A), a compound represented by the following formula (A1), etc. are mentioned, for example.

In the above formula (A1), R ²¹ represents a hydrogen atom or a methyl group (hereinafter, sometimes represented by "Me"). A plurality of R ²¹ may be the same or different.

In the above formula (A1), R ²² represents a hydrocarbon group (preferably 1 to 6 carbon atoms). Specific examples of the hydrocarbon group are as described above. A plurality of R ²² may be the same or different.

In the above formula (A1), R ²³ represents a hydrogen atom or a hydrocarbon group (preferably 1 to 18 carbon atoms). Specific examples of the hydrocarbon group are as described above. A plurality of R ²³ may be the same or different.

In the formula (A1), R ²⁴ represents a divalent organic group. As a divalent organic group, for example, a substituted or unsubstituted aliphatic hydrocarbon group (eg, an alkylene group, preferably 1 to 8 carbon atoms), a substituted or unsubstituted aromatic hydrocarbon group (eg, an arylene group Preferably, 6 to 12 carbon atoms), -O-, -S-, -SO ₂ -, -N(R)-(R: alkyl group), -CO-, -NH-, -COO-, -CONH- , Or a combination of these groups (for example, an alkyleneoxy group (-C _m H2 _m O-: m is a positive integer), an alkyleneoxycarbonyl group, an alkylenecarbonyloxy group, etc.), and the like.

In the formula (A1), R ²⁵ and R ²⁶ represent a hydrocarbon group which may have a hetero atom. Specific examples of the hydrocarbon group which may have a hetero atom are as described above. R ²⁵ and R ²⁶ may be the same or different.

In the above formula (A1), l represents a positive integer. Especially, it is preferable that it is an integer of 1-500, and it is more preferable that it is an integer of 3-300.

In the formula (A1), n represents an integer of 0 to 2. Especially, it is preferable that it is an integer of 1 or more from the reason excellent in adhesiveness with an adherend.

The compound represented by the above formula (A1) is preferably 5 to 50 mol% of the group bonded to the silicon atom is an aryl group, and 10 to 30 mol% is an aryl group from the reason that the cured product has more excellent heat resistance and toughness. More preferable.

The weight average molecular weight (Mw) of the polysiloxane (A) is not particularly limited, but it is preferably 100 to 1,000,000, and more preferably 500 to 50,000 from the reasons of excellent toughness and elongation of the cured product.

In addition, in the present application, the weight average molecular weight is a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC) using chloroform as a solvent.

In addition, the viscosity of the polysiloxane (A) at 25° C. is preferably 20 to 1,000,000 mPa·s, and more preferably 200 to 100,000 mPa·s.

Incidentally, in the present application, the viscosity is measured at 25°C in accordance with 4.1 (Brookfield type rotational viscometer) of JIS K7117-1.

In the composition of the present invention, the content of the polysiloxane (A) is not particularly limited, but since it is excellent in toughness and elongation of the cured product, it is preferably 10 to 90% by mass, and more preferably 30 to 70% by mass.

(Synthesis method of polysiloxane (A))

The method for synthesizing polysiloxane (A) is not particularly limited, for example, by reacting polysiloxane (a1) with a monomer (a2) having a (meth)acryloyl group, and at least one (meth)acryloyl group per molecule. A method of obtaining a polysiloxane having, etc. are mentioned.

Among these, it is preferable that it is a method of reacting a polysiloxane (a11) having a silanol group at its terminals (preferably both ends) and an alkoxysilane (a21) having a (meth)acryloyl group. It is preferable that the alkoxysilane (a21) having a (meth)acryloyl group has two or more alkoxy groups from the viewpoint of excellent adhesion to an adherend.

As another suitable aspect of the method of synthesizing polysiloxane (A) by reacting polysiloxane (a1) with a monomer (a2) having a (meth)acryloyl group, for example, hydroxy at the terminal (preferably both ends) A method of reacting a polysiloxane (a12) having an alkyl group (-R-OH: R is an alkylene group) and an isocyanate (a22) having a (meth)acryloyl group may be mentioned.

In addition, as another suitable embodiment of the method of synthesizing polysiloxane (A) by reacting polysiloxane (a1) with a monomer (a2) having a (meth)acryloyl group, polysiloxane (a13) having an epoxy group and (meth)acrylic acid are used. The method of making it react, etc. are mentioned.

The polysiloxane (a1) used in the synthesis of the polysiloxane (A) preferably has an aryl group because the cured product has excellent transparency and the cured product has more excellent heat resistance. Specific examples and suitable embodiments of the aryl group are as described above.

<Silicone resin (B)>

The silicone resin (B) used in the composition of the present invention is a silicone resin represented by the following average unit formula (1). Here, the following average unit formula (1) shows the number of moles of each siloxane unit when the total siloxane units constituting the silicone resin (B) is 1 mol.

^{_{(R 1 SiO 3/2) a (}} R 2 2 SiO 2/2) b (R 3 3 SiO 1/2) c (SiO 4/2) d (X 1 O 1/2) e ... (One)

In the formula (1), R ¹ , R ² and R ³ each independently contain an aryl group, a (meth)acryloyl group-containing group, an alkyl group (preferably 1 to 10 carbon atoms), a cycloalkyl group, and a vinyl group. It represents an organic group selected from the group consisting of a group and an epoxy group-containing group. A plurality of R ² and R ³ may be the same or different, respectively.

In addition, when there are multiple units (R ¹ SiO _3/2 ) in the silicon resin (B), some units (R ¹ SiO _3/2 ) and other units (R ¹ SiO _3/2 ) are the same or different. It's okay. That is, R ¹ of any units (R ¹ SiO _3/2) R ¹ and the other units (R ¹ SiO _3/2) is of but may be the same. The same applies to (R ² ₂ SiO _2/2 ), (R ³ ₃ SiO _1/2 ), and (X ¹ O _1/2 ).

Specific examples and preferred embodiments of the aryl group are as described above.

The (meth)acryloyl group-containing group is not particularly limited as long as it is a group containing a (meth)acryloyl group, but from the viewpoint of curability, it is preferably a hydrocarbon group having a (meth)acryloyloxy group as a substituent. ) It is more preferable that it is an alkyl group (especially C1-C10) which has an acryloyloxy group as a substituent.

As a suitable aspect of the said (meth)acryloyl group-containing group, a group represented by following formula (B1) is mentioned, for example.

In the formula (B1), R ¹¹ represents a hydrogen atom or a methyl group.

In the formula (B1), R ¹² represents a divalent organic group. Specific examples and suitable aspects of the divalent organic group are the same as those of R ²⁴ in Formula (A1) described above.

In the formula (B1), * represents a bonding position.

The vinyl group-containing group is not particularly limited as long as it is a group containing a vinyl group (CH ₂ =CH-) (hereinafter, sometimes represented by “Vi”). As said vinyl group-containing group, a vinyl group, an allyl group, etc. are mentioned, for example, Among them, a vinyl group is preferable.

In the above formula (1), the ratio of the aryl group (hereinafter also referred to as an aryl group ratio) to all organic groups represented by R ¹ , R ² and R ³ (in the total organic group) is 15 mol% or more. Especially, it is preferable that it is 25 mol% or more from the reason that the adhesiveness and transparency of a cured product are excellent. The upper limit is not particularly limited, but it is usually 80 mol% or less, and preferably 70 mol% or less.

For example, 3 mol of the aryl group represented by R ¹ in the silicone resin (B), ² mol of the (meth)acryloyl group-containing group represented by R 2, 5 mol of the alkyl group represented by R ³ exist, and in addition to R ¹ , When the organic group represented by R ² or R ³ does not exist, 10 mol of total organic groups represented by R ¹ , R ² and R ³ exist, and 3 mol of the aryl groups exist, so the aryl group rate is 30 mol% (=3/ 10) becomes.

In the above formula (1), X ¹ represents a group selected from the group consisting of a hydrogen atom and an alkyl group (preferably 1 to 10 carbon atoms). The alkyl group may be linear, branched or cyclic.

In the above formula (1), a, b, c, d and e are,

0<a≤1,

0≤b<1,

0≤c<1,

0≤d<1,

0≤e<1,

0≤b/a≤10,

0≤c/a≤5,

0≤d/(a+b+c+d)≤0.3,

0≤e/(a+b+c+d)≤0.4

Satisfies the relational expression of

It is preferable that b/a is 0-1.0.

As for c/a, it is preferable that it is 0-1.0, and it is more preferable that it is 0.5-0.7.

d/(a+b+c+d) is preferably 0 to 1.0.

It is preferable that e/(a+b+c+d) is 0 to 1.0.

As described above, in the above formula (1), a is an integer (>0). That is, the silicon resin (B) has a branched structure represented by (R ¹ SiO _3/2 ).

It is preferable that the silicone resin (B) has the above-mentioned (meth)acryloyl group-containing group from the reason excellent in adhesiveness of a cured product.

The weight average molecular weight (Mw) of the silicone resin (B) is not particularly limited, but from the viewpoint of toughness and rigidity of the cured product, it is preferably 1,000 to 300,000, and more preferably 1,500 to 100,000.

In the composition of the present invention, the content of the silicone resin (B) is not particularly limited, but is preferably 10 to 200 mass%, more preferably 50 to 150 mass%, based on the content of the polysiloxane (A). .

(Synthesis method of silicone resin (B))

The method of synthesizing the silicone resin (B) is not particularly limited, and examples thereof include a method of dealcohol condensing a trialkoxysilane having an aryl group.

As a suitable aspect of the method for synthesizing the silicone resin (B), a trialkoxysilane (b1) having an aryl group, a trialkoxysilane (b2) having a group containing a (meth)acryloyl group, and a polymerizable group (preferably a vinyl group) A method of dealcoholizing condensation of disiloxane (b3) having, etc. are mentioned. The definition of the (meth)acryloyl group-containing group and a suitable aspect are as described above.

<Monofunctional (meth)acrylic monomer (C)>

It is preferable that the composition of the present invention further contains a monofunctional (meth)acrylic monomer (C) from the reason why it is excellent in flexibility of the cured product. In addition, the (meth)acrylic monomer represents an acrylic monomer or a methacrylic monomer.

The monofunctional (meth)acrylic monomer (C) is not particularly limited, but ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, tri Decyl (meth) acrylate, hexadecyl (meth) acrylate, octadecyl (meth) acrylate, isoamyl (meth) acrylate, isodecyl (meth) acrylate, isostearyl (meth) acrylate, ethoxy Ethoxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, methoxyethyl (meth)acrylate, butoxyethyl (meth) Aliphatic (meth)acrylates such as acrylate and benzyl (meth)acrylate, nonylphenoxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, glycidyl (meth)acrylate, 2-hydride Aromatic (meth)acrylates such as oxy-3-phenoxypropyl (meth)acrylate, nonylphenoxyethyltetrahydrofurfuryl (meth)acrylate, and phenoxyethyl (meth)acrylate, dicyclopentenyl (meth) ) Acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, tetracyclododecanyl (meth) acrylate, cyclohexyl (meth) acrylate, and other alicyclic (脂環式) (meth)acrylate, caprolactone-modified tetrahydrofurfuryl (meth)acrylate, acryloylmorpholine, isobornyl (meth)acrylate, norbornyl (meth)acrylate, 2-(meth) Acryloyloxymethyl-2-methylbicycloheptaneadamantyl (meth)acrylate, and the like.

In addition, the monofunctional (meth)acrylic monomer (C) does not contain a monofunctional (meth)acrylic monomer having a plurality of ester groups.

In the composition of the present invention, the content of the monofunctional (meth)acrylic monomer (C) is not particularly limited, but from the viewpoint of toughness and flexibility of the cured product, it is preferably 10 to 30% by mass relative to the total amount of the composition.

<(meth)acrylate monomer (D) having a plurality of ester groups>

The composition of the present invention, from the viewpoint of toughness and flexibility of a cured product, and adhesion to an adherend, further has a plurality of ester groups (meth)acrylate monomer (D) (hereinafter, only ester group-containing (meth) It may contain an acrylate monomer (D)).

Although it does not specifically limit as an ester group-containing (meth)acrylate monomer (D), It is preferable that it is a compound represented by following formula (D1) from the viewpoint of toughness and flexibility of a cured product, and adhesiveness with an adherend.

In the formula (D1), R ¹¹ represents a hydrogen atom or a methyl group.

In the formula (D1), R ¹² represents a single bond or a divalent organic group. Specific examples and suitable aspects of the divalent organic group are the same as those of R ²⁴ in Formula (A1) described above.

In the formula (D1), n represents an integer of 1 to 25.

In the composition of the present invention, the content of the ester group-containing (meth)acrylate monomer (D) is not particularly limited, but from the viewpoint of toughness and flexibility of the cured product and adhesion to the adherend, the total amount of the composition is 5 It is preferably-30% by mass.

<Photopolymerization initiator>

The composition of the present invention may further contain a photoinitiator.

Although it does not specifically limit as a photoinitiator, For example, acetophenones, benzoin, benzophenones (1-hydroxy-1,2,3,4,5,6-hexahydrobenzophenone, etc.), a force Fin oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, fluoroamine compounds, aromatic sulfoniums, lopin dimers , Onium salts, borate salts, active esters, active halogens, inorganic complexes, coumarins, and the like.

In the composition of the present invention, the content of the photopolymerization initiator is not particularly limited, but from the viewpoint of curability and storage stability, it is preferably 1 to 5% by mass.

<Other ingredients>

The composition of the present invention may further contain additives, as necessary, within a range that does not impair its effects or objects.

Examples of additives include inorganic fillers, antioxidants, lubricants, ultraviolet absorbers, thermal light stabilizers, dispersants, antistatic agents, polymerization inhibitors, defoaming agents, curing accelerators, solvents, inorganic phosphors, anti-aging agents, radical inhibitors, adhesive Improvers, flame retardants, surfactants, storage stability improvers, ozone aging inhibitors, thickeners, plasticizers, radiation blocking agents, nucleating agents, coupling agents, conductivity imparting agents, phosphorus peroxide decomposing agents, pigments, metal deactivating agents, and property modifiers. Various additives are not particularly limited. For example, a conventionally known one can be mentioned.

The method of producing the composition of the present invention is not particularly limited, and examples thereof include a method of producing by mixing the above-described essential ingredients and optional ingredients.

The composition of the present invention can be suitably used for adhesives, primers, sealing materials for electronic devices such as liquid crystal displays, recording media, optical devices, and semiconductor integrated circuits.

Example

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited thereto.

(Synthesis of polysiloxane A1)

Methylphenylpolysiloxane [HO(PhMeSiO)7H] (100g) having silanol groups at both ends, KBM5103 (3-acryloxypropyltrimethoxysilane, Shin-Etsu Chemical Co., Ltd.) (68g), acetic acid (1g) was mixed and reacted at 140°C for 4 hours to synthesize methylphenylpolysiloxane having acryloyl groups at both ends. Let the obtained methylphenylpolysiloxane be polysiloxane A1. Polysiloxane A1 has the following structure, has an aryl group (phenyl group) and an alkoxy group (methoxy group), and further has an acryloyl group at both ends.

(Synthesis of polysiloxane A2)

Both terminal carbinol-modified methylphenylpolysiloxane [HOCH ₂ CH ₂ (PhMeSiO) ₆ PhMeSiCH ₂ CH ₂ OH, Mw: 5,000] (100 g), 2-isocyanate ethyl acrylate (5 g), Neostan U-28 (inorganic metal catalyst, Nitto Kasei Co., Ltd. product) (concentration for reaction solution: 20 ppm) was mixed and reacted at 70° C. for 2 hours to synthesize methylphenylpolysiloxane having acryloyl groups at both ends. Let the obtained methylphenylpolysiloxane be polysiloxane A2. Polysiloxane A2 has the following structure, has an aryl group (phenyl group) and a urethane bond, and further has an acryloyl group at both ends. In addition, polysiloxane A2 does not have an alkoxy group.

(Synthesis of polysiloxane A3)

Phenyl group-containing epoxy-modified polysiloxane (trade name: X-22-2000, manufactured by Shin-Etsu Chemical Co., Ltd.) (100 g), acrylic acid (20 g), and tetramethylphosphonium bromide (1 g) were mixed, reacted at 100° C. for 5 hours, and side chains A phenyl group-containing polysiloxane having an acryloyl group was synthesized. The obtained phenyl group-containing polysiloxane is referred to as polysiloxane A3. Polysiloxane A3 has an aryl group (phenyl group), and further has an acryloyl group in a side chain. In addition, polysiloxane A3 does not have an alkoxy group.

(Synthesis of polysiloxane A4)

Dimethylpolysiloxane having silanol groups at both ends (trade name: KF9701, manufactured by Shin-Etsu Chemical Co., Ltd.) (100 g), KBM5103 (3-acryloxypropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.) (17 g), acetic acid (1 g) And reacted at 140° C. for 4 hours to synthesize dimethylpolysiloxane having acryloyl groups at both ends. Let the obtained dimethylpolysiloxane be polysiloxane A4. Polysiloxane A4 has an alkoxy group (methoxy group), and further has an acryloyl group at both ends. In addition, polysiloxane A4 does not have an aryl group.

(Synthesis of urethane acrylate X1)

In a reaction vessel equipped with a stirrer, 182.67 g of polypropylene glycol having a number average molecular weight of 1000, 16.48 g of polypropylene glycol having a number average molecular weight of 4000, 0.183 g of 2,6-di-t-butyl-p-cresol, and tolylene diisocyanate 255.14 g, 94.35 g of 2-ethylhexyl acrylate were put, and, stirring these, it cooled until the liquid temperature became 15 degreeC. After the addition of 0.608 g of dibutyltin dilaurate, the mixture was stirred for about 1 hour, taking care not to bring the temperature higher than 40°C. After stirring until it reached room temperature, 87.56 g of 2-hydroxypropyl acrylate was added dropwise while controlling the liquid temperature not to exceed 30°C. After completion of the dropwise addition, the mixture was stirred at a liquid temperature of 40°C for 1 hour. Next, 218.64 g of 2-hydroxyethyl acrylate was added dropwise while controlling the liquid temperature not to exceed 60°C. After completion of the dropping, the mixture was stirred at a liquid temperature of 60°C. When the concentration of the residual isocyanate group became 0.1% by mass or less, the reaction was terminated to obtain a urethane acrylate. The obtained urethane acrylate is referred to as urethane acrylate X1.

(Synthesis of silicone resin B1)

1,3-divinyl-1,1,3,3-tetramethyldisiloxane 64.2 g, water 90 g, trifluoromethanesulfonic acid 0.14 g and toluene in a 4-neck flask equipped with a stirrer, reflux condenser, inlet, and thermometer 200 g was added and mixed, and while stirring, 189 g of KBM103 (phenyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.), 38 g of KBM5103 (3-acryloxypropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.) were dripped over 1 hour After completion of the dropwise addition, heating was refluxed for 1 hour. After cooling, the lower layer was separated, and the toluene solution layer was washed with water 3 times. 100 g of a 5% sodium hydrogencarbonate aqueous solution was added to the washed toluene solution layer, and the mixture was heated to 75°C while stirring, followed by refluxing for 1 hour. After cooling, the lower layer was separated, and the toluene solution layer of the upper layer was washed with water 3 times. The remaining toluene solution layer was concentrated under reduced pressure to obtain a liquid silicone resin. Let the obtained silicone resin be silicone resin B1.

NMR analysis was performed on the silicone resin B1, and the average unit formula was as follows.

(PhSiO _3/2 ) _0.53 (AcSiO _3/2 ) _0.09 (ViMe ₂ SiO _1/2 ) _0.38

Here, Ac represents -C ₃ H ₆ OC(=O)CH=CH ₂ .

Silicone resin B1 has an acryloyl group.

The aryl group ratio of silicone resin B1 is 30 mol%.

(Synthesis of silicone resin B2)

A silicone resin was obtained by following the same procedure as the synthesis of silicone resin B1, except that the amount of KBM103 was set to 94.5 g and the amount of KBM5103 was set to 76 g. Let the obtained silicone resin be silicone resin B2.

When NMR analysis was performed on the silicone resin B2, the average unit formula was as follows.

(PhSiO _3/2 ) _0.32 (AcSiO _3/2 ) _0.22 (ViMe ₂ SiO _1/2 ) _0.46

Here, Ac represents -C ₃ H ₆ OC(=O)CH=CH ₂ .

Silicone resin B2 has an acryloyl group.

The aryl group ratio of silicone resin B2 is 17 mol%.

(Synthesis of silicone resin B3)

A silicone resin was obtained by following the same procedure as the synthesis of silicone resin B1 except that KBM5103 was not added. Let the obtained silicone resin be silicone resin B3.

When the NMR analysis was performed about the silicone resin B3, the average unit formula was as follows.

(PhSiO _3/2 ) _0.58 (ViMe ₂ SiO _1/2 ) _0.42

Silicone resin B3 does not have a (meth)acryloyl group.

The aryl group ratio of silicone resin B3 is 32 mol%.

(Synthesis of silicone resin X1)

Except that the amount of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane was 68 g, the amount of KBM103 was 9.9 g, and the amount of KBM5103 was 51 g, the silicone resin B1 A silicone resin was obtained by following the same procedure as for synthesis. Let the obtained silicone resin be silicone resin X1.

NMR analysis was performed on the silicone resin X1, and the average unit formula was as follows.

(PhSiO _3/2 ) _0.05 (AcSiO _3/2 ) _0.22 (ViMe ₂ SiO _1/2 ) _0.73

Here, Ac represents -C ₃ H ₆ OC(=O)CH=CH ₂ .

The aryl group ratio of the silicone resin X1 is 2 mol%.

<Examples 1 to 10, Comparative Examples 1 to 3>

The components shown in Table 1 below were used in amounts (unit: parts by mass) shown in the table, and these were uniformly mixed with a vacuum stirrer to prepare a curable resin composition.

<Adhesion strength>

The obtained curable resin composition was applied to a glass plate (applied area: φ5 mm, applied thickness: 0.3 mm), and another glass plate was attached to the applied portion with a crisscross. Thereafter, light irradiation (accumulated light amount: 3,000 mJ/cm ² ) using a light irradiation device (device name: GS UVSYSTEM TYPE S250-01, light source: metal hydro lamp, GS Yuasa International Ltd.) ) And cured. In this way, a sample for evaluating the adhesive strength was prepared.

The prepared sample was evaluated for adhesive strength by a tensile test. Specifically, when using a tensile tester to fix one side of the glass plate pasted with a crisscross, pull the other glass plate at a tensile speed of 5 mm/min, and the glass plate pasted with a crisscross is peeled off. The maximum tensile strength of was measured. This was taken as the adhesive strength.

Further, a high-temperature, high-humidity environmental test (85°C, RH85%, 1000 hours) was performed on the prepared sample, and then, the adhesive strength was evaluated by the same method as the above-described method.

Table 1 shows the adhesive strength before and after the high-temperature, high-humidity environmental test and the adhesive strength retention rate (=adhesive strength after test/adhesive strength before test).

Practically, from the viewpoint of heat resistance, the adhesive strength retention is preferably 80% or more.

<Appearance after high temperature and high humidity environmental test>

A sample for evaluation was prepared by a method similar to the adhesive strength. The produced sample was subjected to a high-temperature, high-humidity environmental test (85°C, RH85%, 1000 hours), and then, the appearance was observed visually. Table 1 shows the appearance after the high-temperature, high-humidity environmental test.

<Transmittance>

A sample for evaluation was prepared by a method similar to the adhesive strength. In accordance with JIS K0115:2004, the transmittance at a wavelength of 400 nm was measured using an ultraviolet/visible absorption spectrum measuring device (manufactured by Shimadzu Corporation). The results are shown in Table 1.

The details of each component shown in the said 1st table are as follows.

Polysiloxane A1: Polysiloxane A1 synthesized as described above

Polysiloxane A2: Polysiloxane A2 synthesized as described above

Polysiloxane A3: Polysiloxane A3 synthesized as described above

Polysiloxane A4: Polysiloxane A4 synthesized as described above

Urethane acrylate X1: Urethane acrylate X1 synthesized as described above

Silicone resin B1: Silicone resin B1 synthesized as described above

Silicone resin B2: Silicone resin B2 synthesized as described above

Silicone resin B3: Silicone resin B3 synthesized as described above

Silicone resin X1: Silicone resin X1 synthesized as described above

Monofunctional acrylic monomer C1: dicyclopentenyl acrylate

Monofunctional acrylic monomer C2: isobornyl acrylate

Monofunctional acrylic monomer C3: isodecyl acrylate

Ester group-containing acrylate monomer D1: Fraxel FM1 (compound represented by the formula (D1), molecular weight: 244, manufactured by DAICEL CORPORATION)

Ester group-containing acrylate monomer D2: Fraxel FM3 (compound represented by the formula (D1), molecular weight: 473, manufactured by Daicel Corporation)

Photoinitiator: Irgacure 184 (manufactured by BASF Corporation)

As can be seen from Table 1, in Comparative Examples 1 and 2 using urethane acrylate, the adhesive strength decreased after the high-temperature, high-humidity environmental test, and the appearance changed from colorless transparent to pale yellow transparent.

In addition, it contains polysiloxane (A) having at least one (meth)acryloyl group per molecule, but does not contain the silicone resin (B) represented by the average unit formula (1) (the aryl group ratio is less than 15 mol% It contains silicone resin) In Comparative Example 3 as well, after the high-temperature, high-humidity environmental test, the adhesive strength was lowered, and the appearance changed from colorless transparent to pale yellow transparent.

On the other hand, in the examples of the present application containing polysiloxane (A) having at least one (meth)acryloyl group per molecule, and silicone resin (B) represented by the average unit formula (1), in any one Almost no decrease in adhesive strength was observed by the high-humidity environmental test, and no change in appearance was observed by the high-temperature, high-humidity environmental test. That is, it showed excellent heat resistance.

Among them, Examples 1 to 5 and 7 to 9 in which polysiloxane (A) has a (meth)acryloyl group "at the end" have higher adhesive strength (even before and after the high temperature and high humidity environmental test), and are excellent in adhesion. I got it. Among them, Examples 1 to 5, 7 and 9 in which the silicone resin (B) has a (meth)acryloyl group had higher adhesive strength before the high-temperature, high-humidity environmental test, and were excellent in adhesion.

From the comparison with Examples 1 and 2, compared to Example 2 in which the aryl group ratio of the silicone resin (B) is less than 25 mol%, Example 1 in which the aryl group ratio of the silicone resin (B) is 25 mol% or more is (high temperature, high humidity environment Both before and after the test) the adhesive strength was higher, and the adhesiveness was excellent. In addition, the transmittance was high and it was excellent in transparency.

From the comparison with Examples 5 and 6, and the comparison with Examples 9 and 10, as compared to Examples 6 and 10 in which polysiloxane (A) does not have a urethane bond, polysiloxane (A) has a urethane bond. Examples 5 and 9 had higher adhesive strength (even before and after the high temperature and high humidity environmental test) and were excellent in adhesion.

From the contrast of Examples 1 to 10, Examples 1 to 4 and 8 in which the polysiloxane (A) has an aryl group and an alkoxy group have high transmittance and excellent transparency.

Claims (8)

A curable resin composition comprising a polysiloxane (A) having at least one (meth)acryloyl group per molecule, and a silicone resin (B) represented by the following average unit formula (1).
(R ¹ SiO _3/2 ) _a (R ² ₂ SiO _2/2 ) _b (R ³ ₃ SiO _1/2 ) _c (SiO _4/2 ) _d (X ¹ O _1/2 ) _e … (One)
(In formula (1), R ¹ , R ² and R ³ are each independently selected from the group consisting of an aryl group, a (meth)acryloyl group-containing group, an alkyl group, a cycloalkyl group, a vinyl group-containing group, and an epoxy group-containing group. A plurality of R ² and R ³ may be the same or different, respectively The ratio of the aryl group to all organic groups represented by R ¹ , R ² and R ³ is 25 mol% or more. X ¹ is hydrogen Represents a group selected from the group consisting of an atom and an alkyl group, a, b, c, d and e are,
0<a≤1,
0≤b<1,
0≤c<1,
0≤d<1,
0≤e<1,
0≤b/a≤10,
0≤c/a≤5,
0≤d/(a+b+c+d)≤0.3,
0≤e/(a+b+c+d)≤0.4
Satisfies the relational expression of.) The method of claim 1,
The curable resin composition, wherein the silicone resin (B) has a (meth)acryloyl group. The method according to claim 1 or 2,
The curable resin composition in which the polysiloxane (A) has an aryl group. The method according to claim 1 or 2,
The curable resin composition in which the polysiloxane (A) has an alkoxy group. The method according to claim 1 or 2,
The curable resin composition, wherein the polysiloxane (A) has a urethane bond. The method according to claim 1 or 2,
Furthermore, the curable resin composition containing a monofunctional (meth)acrylic monomer (C) and a photoinitiator. The method according to claim 1 or 2,
Furthermore, a curable resin composition containing a (meth)acrylate monomer (D) having a plurality of ester groups. delete