JP2020059771A - Thiol modified silicone compound, dispersant, silicone treated zirconia, zirconia-silicone oil dispersant, cured article, and silicone led encapsulation material - Google Patents

Abstract

To provide a thiol modified silicone compound capable of providing an LED encapsulation material having heat resistance and light resistance, and further high refraction index and transparency, a dispersant, a silicone treated zirconia, a zirconia-silicone oil dispersant, a cured article, and a silicone LED encapsulation material.SOLUTION: There are provided a thiol modified silicone compound in which a single terminal or both terminals is modified by a monovalent group represented by the formula (1); a dispersant having a silicone structure, and a dicarboxylic acid anhydride structure at a single terminal of the silicone structure; silicone treated zirconia surface treated by the dispersant; a zirconia-silicone oil dispersant by dispersing the silicone treated zirconia in a silicone oil and a curd article thereof; and a silicone LED encapsulation material containing the cured article. In the formula, *represents a binding position to the silicone compound.SELECTED DRAWING: None

Description

  The present invention relates to a thiol-modified silicone compound, a dispersant, a zirconia treated with silicone, a zirconia-silicone oil dispersion, a cured product, and a silicone LED encapsulant.

  An LED encapsulant is used for a light emitting diode (LED) for the purpose of protecting the light emitting element from moisture and dust in the atmosphere. An epoxy encapsulant or a silicone encapsulant has been conventionally used as the LED encapsulant. The epoxy encapsulant has a high refractive index of 1.51 to 1.55 and excellent light extraction efficiency, but has a problem of relatively poor heat resistance and light resistance. Low-refractive index type and high-refractive index type (phenyl group-modified) are known as silicone encapsulants. Although the low-refractive index type has excellent heat resistance and light resistance, it has a refractive index of 1.41. The light extraction efficiency is low, and the high refractive index type has a high refractive index of 1.51 to 1.53 and excellent light extraction efficiency, but has a problem of poor heat resistance and light resistance. Therefore, there has been a demand for an LED encapsulant having heat resistance and light resistance, and having both a high refractive index and transparency.

In a low refractive index type silicone encapsulant having excellent heat resistance and light resistance, it has been attempted to add an inorganic filler to improve the refractive index. Patent Document 1 describes a surface treatment method for an inorganic filler, which comprises treating the surface of the inorganic filler with an organic acid anhydride represented by the following general formula (A).
[In the formula, R ^1a represents a group having 2 to 10 carbon atoms forming a cycloalkane, a group having 2 to 10 carbon atoms forming a cycloalkene, a group having 3 to 11 carbon atoms forming a bicycloalkane, and forming a bicycloalkene. Represents a group having 3 to 11 carbon atoms or a group having 4 to 12 carbon atoms forming an aromatic ring, and R ^2a represents hydrogen, an alkyl group, an alkoxy group, a halogen group, a nitro group, a methacryl group, an acryl group, or vinyl. group, an epoxy ^group, group having 2 to 10 carbon atoms to form a cycloalkane contains carbon of ^{R 1a,} group having a carbon number of 2-10 to form a cycloalkene contain carbon of ^{R 1a,} carbons ^{R 1a} It shows a group selected from a group having 4 to 12 carbon atoms to form an aromatic ring and a group having 1 to 4 carbon atoms to form a heterocycle by containing the carbon of R ^1a . ]
However, in the hybrid thin film in which the inorganic filler surface-treated by the above-mentioned surface treatment method is dispersed, there is room for improvement in permeability due to the dispersion of the inorganic filler and the like.

JP, 2017-210597, A

  Therefore, an object of the present invention is to provide an LED encapsulant having heat resistance and light resistance, and having both high refractive index and transparency, a thiol-modified silicone compound, a dispersant, a silicone-treated zirconia, and a zirconia-silicone. An object is to provide an oil dispersion, a cured product, and a silicone LED encapsulant.

  The present inventors have conducted extensive studies in view of the above problems, and have a heat resistance and a light resistance by a novel dispersant having a silicone structure and a dicarboxylic acid anhydride structure at one end of the silicone structure, The inventors have found that an LED encapsulant having both a higher refractive index and transparency can be obtained, and completed the present invention.

That is, the thiol-modified silicone compound of the present invention has one end or both ends modified with a monovalent group represented by the following formula (1).
[In the above formula (1), * ¹ represents the bonding position to the silicone compound. ]

Further, the dispersant of the present invention has a silicone structure and a dicarboxylic acid anhydride structure at one end of the silicone structure.
Furthermore, the silicone-treated zirconia of the present invention is surface-treated with the above dispersant.
Furthermore, the zirconia-silicone oil dispersion of the present invention is a dispersion of the above-mentioned silicone-treated zirconia in silicone oil.
Furthermore, the cured product of the present invention is a cured product of the zirconia-silicone oil dispersion.
Furthermore, the silicone LED encapsulant of the present invention contains the above cured product.

  According to the present invention, a thiol-modified silicone compound, a dispersant, a silicone-treated zirconia, a zirconia-silicone oil dispersion, which can provide an LED encapsulant having heat resistance and light resistance, and having both a high refractive index and transparency. A body, a cured product, and a silicone LED encapsulant can be provided.

It is a chart graph of the total light transmittance of an Example and a comparative example.

1. Thiol-modified silicone compound The thiol-modified silicone compound of the present invention has one end or both ends modified with a monovalent group represented by the following formula (1).
In the above formula (1), * ¹ represents the bonding position to the silicone compound.

  Examples of the thiol-modified silicone compound of the present invention include a compound represented by the following formula (11) whose one end is thiol-modified, and a compound represented by the following formula (12) which is thiol-modified. To be

In the above formula (11), R ¹ represents a monovalent hydrocarbon group having 1 to 8 carbon atoms, and R ² represents a single bond or a divalent organic group having 1 to 8 carbon atoms. n represents an integer of 1 to 600.

In the above formula (12), R ² and R ³ are the same or different and each represents a single bond or a divalent organic group having 1 to 8 carbon atoms. n is the same as in the above formula (11).

Examples of the monovalent hydrocarbon group having 1 to 8 carbon atoms include saturated hydrocarbon groups such as methyl group, ethyl group, propyl group, butyl group and t-butyl group; unsaturated hydrocarbon groups such as vinyl group and allyl group. Group; alicyclic hydrocarbon group such as cyclohexyl group; aromatic hydrocarbon group such as phenyl group and the like.
The divalent organic groups of 1 to 8 carbon atoms, a methylene group, an ethylene group, a propylene group, such as butene hydrocarbon _{group; -C 3 H 6 OC 2 H} 4 - hydrocarbons having an ether bond, such as Group; and the like.

1-1 Method for producing thiol-modified silicone compound Examples of the method for producing a thiol-modified silicone compound include a method of esterifying a silicone compound having a hydroxyl group at one end or both ends with β-mercaptopropionic acid. As an example, the following formula (13) shows a method for producing a thiol-modified silicone compound in which one end is thiol-modified by esterifying a β-mercaptopropionic acid with a silicone compound having a hydroxyl group at one end.

In the above formula ^(13), R 1, ^{R 2} and n are the same as ^R 1, ^{R 2} and n in the above formula (11).

  The thiol-modified silicone compound whose both ends are thiol-modified can be obtained in the same manner as in the above formula (13) by subjecting a silicone compound having hydroxyl groups at both ends to an esterification reaction of β-mercaptopropionic acid.

  As the silicone compound having a hydroxyl group at one end or both ends, commercially available compounds can be used, and examples thereof include FM-4411, FM-4421, FM-4425, FM-0411, FM-0421, FM-0425 manufactured by JNC. , FM-DA11, FM-DA21, FM-DA26; Shin-Etsu Silicone Co., Ltd. KF-6000, KF-6001, KF-6002, KF-6003, KF-2201, X-21-5841, KF-9701, X. -22-176DX, X-22-176F, X-22-176GX-A and the like can be mentioned.

In the above esterification reaction, a solvent or a catalyst may be used if necessary. As the solvent that can be used, hexane, heptane, octane, cyclohexane, benzene, toluene, ethylbenzene, xylene, ethyl acetate, butyl acetate, isobutyl acetate, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, dichloromethane, chloroform, dimethyl sulfoxide, dimethylformamide, dimethyl. Examples include acetamide.
Examples of usable catalysts include acid catalysts such as nitric acid, hydrochloric acid, sulfuric acid, acetic acid, formic acid, methanesulfonic acid and p-toluenesulfonic acid.

  The esterification reaction is preferably performed at 100 ° C or higher and 200 ° C or lower.

  According to the novel thiol-modified silicone compound of the present invention, which will be described later, having heat resistance and light resistance, it is possible to provide an LED encapsulant having both high refractive index and transparency, a dispersant, a silicone-treated zirconia, A zirconia-silicone oil dispersion, a cured product, and a silicone LED encapsulant can be provided.

2. Method for producing dicarboxylic acid anhydride-modified silicone compound The thiol-modified silicone compound of the present invention can be used for synthesizing a dicarboxylic acid anhydride-modified silicone compound. Examples of the method for producing the dicarboxylic acid anhydride-modified silicone compound include a thiol-modified silicone compound represented by the above formula (11) and a carbon-carbon double bond as represented by the following formula (21). A method of reacting with a dicarboxylic acid anhydride can be mentioned. According to the reaction formula of the following formula (21), a silicone compound whose one end is modified with a dicarboxylic acid anhydride is obtained.

In the above formula ^(21), R 1, ^{R 2} and n are the same as ^R 1, ^{R 2} and n in the above formula (11). R ¹¹ represents a divalent hydrocarbon group having a carbon-carbon double bond having 2 to 12 carbon atoms, and R ⁴ represents a trivalent hydrocarbon group having 2 to 12 carbon atoms and corresponding to R ^11. .

  Examples of the divalent hydrocarbon group having a carbon-carbon double bond having 2 to 12 carbon atoms include a vinylene group; a group having 3 to 12 carbon atoms forming a cycloalkene; and a carbon group having 4 to 12 carbon atoms forming a bicycloalkene. A group having 5 to 12 carbon atoms forming a tricycloalkene, and the like. These groups may have a substituent. Examples of the substituent include a linear or branched alkyl group having 1 to 10 carbon atoms and the like, and the substituent may have a plurality of different substituents.

  Specific examples of the dicarboxylic acid anhydride having a carbon-carbon double bond include compounds represented by the following formulas.

Of these, R ¹¹ is preferably a vinylene group or a group having 4 to 12 carbon atoms forming a bicycloalkene, and examples of the dicarboxylic acid anhydride having a carbon-carbon double bond include maleic anhydride and 5-norbornene 2 , 3-dicarboxylic acid anhydride is particularly preferred.

  The silicone compound whose both terminals are modified with a dicarboxylic acid anhydride can be obtained in the same manner as in the above formula (21) using the compound represented by the above formula (12).

  The dicarboxylic acid anhydride having a carbon-carbon double bond is preferably reacted at a ratio of 1.0 to 1.5 mol with respect to 1 mol of the thiol group contained in the thiol-modified silicone compound.

  In the above reaction, a solvent may be used if necessary, and the same solvent as in the method for producing the thiol-modified silicone compound can be used.

  The above reaction may be carried out under ultraviolet light if necessary, and it is preferable to use ultraviolet light having a wavelength of 200 to 400 nm.

  As another method for producing a dicarboxylic acid anhydride-modified silicone compound, a method of reacting with a platinum catalyst as represented by the following formula (22) can also be used. According to the reaction formula of the following formula (22), a silicone compound having one end modified with a dicarboxylic acid anhydride can be obtained.

In the above formula ^{(22), R 1, R} 4, R 11 and n are the same as ^{R 1, R 4, R 11} and n in the formula (21).

The silicone compound whose both terminals are modified with a dicarboxylic acid anhydride can be obtained in the same manner as in the above formula (22) using a compound in which R ¹ is hydrogen.

  Regarding the method for producing the dicarboxylic acid anhydride-modified silicone compound, in the method of the above formula (21), since no metal catalyst is used, the influence of metal ions can be suppressed in the dispersant and silicone-treated zirconia described later.

3. Dispersant The dispersant of the present invention has a silicone structure and a dicarboxylic acid anhydride structure at one end of the silicone structure. In the present invention, “having a dicarboxylic acid anhydride structure at one end of the silicone structure” means having a dicarboxylic acid anhydride structure only at one end of the silicone structure, and both ends of the silicone structure are shown. Those having a dicarboxylic acid anhydride structure are excluded.

  Examples of the silicone structure include a monovalent group represented by the following formula (31).

In the above formula (31), ^{R 1} and n are the same as ^{R 1} and n in the above formula (11). * ¹ indicates the bonding position to the group having a dicarboxylic acid anhydride structure.

Examples of the dicarboxylic acid anhydride structure include a monovalent group represented by the following formula (32), and a monovalent group derived from the dicarboxylic acid anhydride having a carbon-carbon double bond is preferable.
In the above formula (32), ^{R 4} is the same as ^{R 4} in the formula (21). In addition, * ² represents the bonding position to the sulfur atom in the silicone structure or the thiol-modified group of the silicone structure.

  As the dicarboxylic acid anhydride structure, monovalent groups represented by the following formula (321) and the following formula (322) can be more preferably used.

In the formula (321) and the formula (322), * ² is the same as the formula (32).

  Examples of the dispersant of the present invention include a compound having a dicarboxylic acid anhydride structure at one end as represented by the following formula (33) and a dicarboxylic acid anhydride structure as represented by the following formula (34). And a compound having two or more silicone structures as represented by the following formula (35).

In the above formula (33), ^{R 1} and n are the same as ^{R 1} and n in the above formula (11), ^{R 4} is the same as ^{R 4} in the formula (32). X ¹ is a single bond or a divalent group represented by the following formula (331).

In the formula (331), ^{R 2} is the same as ^{R 2} in the formula (11), ^{* 1} is the same as ^{* 1} in the formula (1), ※ ² binding to the dicarboxylic acid anhydride structure Indicates the position.

In the above formula (34), R ¹ and R ⁶ are the same or different and are the same as R ^{1 in the} above formula (11), and R ² , R ⁷ and R ⁸ are the same or different, respectively, It is the same as R ^{2 in the} above formula (11), R ⁴ and R ⁵ are the same or different and are the same as R ^{4 in the} above formula (32), and n is the same as n in the above formula (11). Is.

In the above formula (35), R ¹ and R ⁹ are the same or different and are the same as R ^{1 in the} above formula (11), and R ² and R ¹⁰ are the same or different and are respectively the above formula (11). ) is the same as ^{R 2} of, ^{R 4} is the same as ^{R 4} in the formula (32), the n1 and n2 are identical or different and each is the same as n in the formula (11).

  The dispersant of the present invention, as represented by the above formula (21), reacts the thiol-modified silicone compound represented by the above formula (11) with a dicarboxylic acid anhydride having a carbon-carbon double bond. Can be obtained. It can also be obtained by the method represented by the above formula (22).

  According to the dispersant of the present invention, the heat-resistant and light-resistant, which will be described later, can provide an LED encapsulant having both high refractive index and transparency, silicone-treated zirconia, zirconia-silicone oil dispersion, A cured product and a silicone LED encapsulant can be provided.

4. Silicone-treated zirconia The silicone-treated zirconia of the present invention is zirconia that has been surface-treated with the above dispersant.

Examples of the silicone-treated zirconia of the present invention include compounds represented by the following formula (41), formula (42) and formula (43).
In the above formula ^{(41), R 1, R} 4, X 1 and n are the same as ^{R 1, R 4, X} 1 and n in the above formula (33).

In the above formula (42), R ¹ , R ² , R ⁴ , R ⁵ , R ⁶ , R ⁷ , and R ⁸ and n are R ¹ , R ² , R ⁴ , R ⁵ , and R ⁶ of the above formula (34). , R ⁷ , R ⁸ and n.

In the above formula ^{(43), R 1, R} 2, R 4, R 9, R 1 of ^R 10, n1 and n2 are the formula ^{(35), R 2, R} 4, R 9, R 10, n1 and n2 Is the same as.

4-1 Method for Producing Silicone Treated Zirconia The method for producing silicone treated zirconia of the present invention comprises, for example, a reaction of surface treating zirconia particles with a dispersant in the presence of a catalyst as represented by the following formula (44). Can be mentioned.
In the above formula ^{(44), R 1, R} 4, X 1 and n are the same as ^{R 1, R 4, X} 1 and n in the above formula (41).

Examples of the catalyst include tertiary amines such as N-ethyldiisopropylamine, triethylamine, tributylamine, 1,4-diazabicyclo [2.2.2] octane; dipropylamine, dibutylamine, piperidine, hexamethyleneimine, etc. Alkaline catalysts such as secondary amines can be used.
As the solvent, hexane, heptane, octane, cyclohexane, benzene, toluene, ethylbenzene, xylene, ethyl acetate, butyl acetate, isobutyl acetate, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, dichloromethane, chloroform, dimethylsulfoxide, dimethylformamide, dimethylacetamide, etc. Is mentioned.

  Further, as another method for producing the silicone-treated zirconia of the present invention, as represented by the following formula (45), the zirconia particles are surface-treated with a dicarboxylic acid anhydride and then represented by the following formula (46). Thus, a manufacturing method in which a dicarboxylic acid anhydride is reacted with a thiol-modified silicone compound can be mentioned.

In the above formula ^{(45), R 11} is the same as ^{R 11} in the formula (21).

  As the catalyst and the solvent, the same ones as exemplified in the above formula (44) can be used.

In the above formula ^(46), similar to R 1, similarly to ^R 1, ^{R 2} and n of ^{R 2} and n are above formula (11), ^{R 4} is ^{R 4} in the formula ^{(41), R 11} is the formula It is the same as R ^{11 of} (45).

  The UV in the formula (46) is the same as the UV used in the formula (21).

  Further, there is also a production method in which the zirconia particles are surface-treated with a dicarboxylic acid anhydride as represented by the above formula (45) and then reacted with a platinum catalyst as represented by the following formula (47). .

In the above formula ^{(47), R 1, R} 4, R 11 and n are the same as ^{R 1, R 4, R 11} and n in the formula (46).

The zirconia particles are not particularly limited, and known particles can be used. It is preferable to use 5% by mass to 100% by mass of the dispersant based on 100% by mass of the zirconia particles.
Further, in addition to the above, the particle size of the zirconia particles is preferably 1 nm to 100 nm.

  Further, a known dispersant other than the dispersant of the present invention may also be included.

5. Zirconia-Silicone Oil Dispersion The zirconia-silicone oil dispersion of the present invention is a dispersion of the above silicone-treated zirconia in silicone oil.
The content of the silicone-treated zirconia is preferably 10% by mass to 80% by mass, and more preferably 30% by mass to 80% by mass, based on 100% by mass of the zirconia-silicone oil dispersion of the present invention.

The silicone oil is not particularly limited, and existing ones can be used.
The content of the silicone oil is preferably 20% by mass to 90% by mass, and more preferably 20% by mass to 70% by mass, based on 100% by mass of the zirconia-silicone oil dispersion.

  According to the silicone-treated zirconia of the present invention, which will be described later, it is possible to provide an LED encapsulant having heat resistance and light resistance, and further having high refractive index and transparency, a zirconia-silicone oil dispersion, a cured product, Also, a silicone LED encapsulant can be provided.

6. Cured Product The cured product of the present invention is a cured product of the zirconia-silicone oil dispersion. Curing can be performed by heating with a Pt catalyst at a temperature of about 150 ° C. for about 2 hours, for example. At the time of curing, a curing initiator, a silane coupling agent, a filler, a pigment, a dye or the like may be added to the zirconia-silicone oil dispersion.
The content of silicone-treated zirconia is preferably 10% by mass to 80% by mass, more preferably 30% by mass to 80% by mass, based on 100% by mass of the cured product of the present invention.

  The cured product of the present invention may contain a filler, a pigment, a dye and the like in addition to the zirconia-silicone oil dispersion. According to the cured product of the present invention, it is possible to provide a silicone LED encapsulant, which can provide an LED encapsulant having heat resistance and light resistance, and having both a high refractive index and high transparency, which will be described later.

7. Silicone LED encapsulant The silicone LED encapsulant of the present invention contains the above cured product. The silicone LED encapsulant of the present invention may contain a filler, a pigment, a dye or the like, if necessary, in addition to the above-mentioned cured product. According to the silicone LED encapsulant of the present invention, it is possible to provide an LED encapsulant having heat resistance and light resistance, and having both a high refractive index and transparency.

  Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

<Example 1>
-Synthesis of thiol-modified silicone (A-1) Carbitol-modified silicone oil [manufactured by JNC Co., product name: Silaplane FM-0425] 31.45 g and β-mercaptopropionic acid [manufactured by SC Organic Co., Ltd.] : BMPA] 0.33 g, toluene 74.15 g, and p-toluenesulfonic acid [Tokyo Chemical Industry Co., Ltd.] 0.16 g were charged into a three-necked flask, and mixed at 115 ° C. for 3 hours for esterification. The catalyst was removed by washing with water to obtain a toluene solution containing 30.0 wt% of thiol-modified silicone (A-1).

-Synthesis of dispersant (B-1) having silicone structure and dicarboxylic acid anhydride structure 68.63 g of toluene solution containing 30.0 wt% of thiol-modified silicone (A-1) and 0.20 g of maleic anhydride in a beaker The solution is completely melted, then the surroundings are cooled with ice, and UV irradiation is performed for 3 minutes using a spot UV irradiator, Spot Cure SP-11 (manufactured by Ushio Inc.) to carry out the enthiol reaction. A toluene solution containing 30.2 wt% of B-1) was obtained.

-Production of silicone-treated zirconia (C-1) Zirconia [manufactured by Shin Nippon Denko Co., Ltd. product name: PCS60, primary particle size 15 nm to 25 nm] 5.0 g, and 30.2 wt% of the dispersant (B-1). Toluene solution 12.5 g, toluene 82.4955 g, catalyst [Kanto Chemical Co., Inc. product name: N-ethyldiisopropylamine] 0.0045 g were used in a batch type Ready Mill RMB-04 [IMEX Co., Ltd.], A bead mill treatment was carried out at a rotation speed of 2650 rpm for 10 minutes to obtain a toluene dispersion liquid containing 8.78 wt% of silicone-treated zirconia (C-1).

-Preparation of zirconia-silicone oil dispersion 0.35 g of vinyl-terminated polydimethylsiloxane (Gelest product name: DMS-V21) and 4.0 g of the above-mentioned silicone-treated zirconia (C-1) toluene dispersion were mixed and desolvated. By performing the treatment, a zirconia-silicone oil dispersion containing 50 wt% of silicone-treated zirconia was obtained.
The refractive index measured using an Abbe refractometer 3L [manufactured by Shimadzu Corporation] was 1.4440. (Table 1)

-Preparation of cured product of zirconia-silicone oil dispersion Vinyl-terminated polydimethylsiloxane (product name: Gelest, product name: DMS-V21) 0.10 g, methyl hydrogen silicone oil [product name: SH-1107, manufactured by Toray Dow Corning Co., Ltd.] ] 0.015g was mixed and the silicone compound (D-1) was obtained.
0.0012 g of platinum catalyst was mixed with 0.10 g of the above zirconia-silicone oil dispersion [vinyl-terminated polydimethylsiloxane (product name: Gelest, product name: DMS-V21), toluene solution of silicone-treated zirconia (C-1) 2.46 g]. After desolvation treatment, the silicone compound (D-1) was mixed therewith.
Then, it was applied on glass to a film thickness of 2 μm and heated at 150 ° C. for 2 hours to obtain a cured product. As a result of measuring the total light transmittance using an ultraviolet-visible spectrophotometer V-750 [manufactured by JASCO Corporation], the total light transmittance (380 nm to 780 nm) was 91.6% (Table 1). FIG. 1 shows a graph of total light transmittance.

<Example 2>
-Synthesis of thiol-modified silicone (A-2) Carbitol-modified silicone oil [JNC Co., Ltd. product name: Silaplane FM-0425] 31.45 g and β-mercaptopropionic acid [SC Organic Co., Ltd. product name : BMPA] 0.33 g, toluene 74.15 g, and p-toluenesulfonic acid [Tokyo Chemical Industry Co., Ltd.] 0.16 g were charged into a three-necked flask, and mixed at 115 ° C. for 3 hours for esterification. The catalyst was removed by washing with water to obtain a toluene solution containing 30.0 wt% of thiol-modified silicone (A-2).

Synthesis of dispersant (B-2) having silicone structure and dicarboxylic acid anhydride structure 61.45 g of toluene solution containing 30.0 wt% of thiol-modified silicone (A-2) and 5-norbornene 2,3-dicarboxylic acid 0.30 g of acid anhydride [manufactured by Tokyo Kasei Kogyo Co., Ltd.] was placed in a beaker and completely dissolved, and then the surroundings were cooled with ice, and a spot UV irradiation device, Spot Cure SP-11 [manufactured by Ushio Inc.] was used. UV irradiation was performed for 3 minutes to carry out the enethiol reaction to obtain a toluene solution containing 30.3 wt% of the dispersant (B-2).

-Production of silicone-treated zirconia (C-2) 5.0 g of zirconia [manufactured by Shin Nihon Denko Co., Ltd., product name: PCS60, primary particle size 15 nm to 25 nm], and 30.3 wt% of the dispersant (B-2). Toluene solution 12.5 g, toluene 82.4955 g, catalyst [Kanto Chemical Co., Inc. product name: N-ethyldiisopropylamine] 0.0045 g were used in a batch type Ready Mill RMB-04 [IMEX Co., Ltd.], A bead mill treatment was performed at a rotation speed of 2650 rpm for 10 minutes to obtain a toluene dispersion liquid containing 8.79 wt% of silicone-treated zirconia (C-2).

-Preparation of zirconia-silicone oil dispersion 0.35 g of vinyl-terminated polydimethylsiloxane (product name: Gelest manufactured by Gelest: DMS-V21) and 4.0 g of a toluene dispersion of the above-mentioned silicone-treated zirconia (C-2) are mixed and desolvated. By performing the treatment, a silicone oil dispersion containing 50 wt% of silicone-treated zirconia was obtained.
The refractive index was 1.4515 when measured using an Abbe refractometer 3L [manufactured by Shimadzu Corporation]. (Table 1)

-Preparation of cured product of zirconia-silicone oil dispersion Vinyl-terminated polydimethylsiloxane (product name: Gelest, product name: DMS-V21) 0.10 g, methyl hydrogen silicone oil [product name: SH-1107, manufactured by Toray Dow Corning Co., Ltd.] ] 0.015g was mixed and the silicone compound (D-2) was obtained.
0.0012 g of a platinum catalyst was added to 0.10 g of the above zirconia-silicone oil dispersion [vinyl-terminated polydimethylsiloxane (product name: Gelest, product name: DMS-V21), 2.46 g of toluene solution of the above-mentioned silicone-treated zirconia (C-2)]. After mixing and desolvation treatment, the silicone compound (D-2) was mixed.
Then, it was applied on glass to a film thickness of 2 μm and heated at 150 ° C. for 2 hours to obtain a cured product. As a result of measuring the total light transmittance using an ultraviolet-visible spectrophotometer V-750 [manufactured by JASCO Corporation], the total light transmittance (380 nm to 780 nm) was 91.3%. (Table 1 and Figure 1)

<Example 3>
-Synthesis of thiol-modified silicone (A-3) Diol-modified silicone oil [Shin-Etsu Silicone Co., Ltd. product name: X-22-176F] 25.00 g and β-mercaptopropionic acid [SC Organic Co., Ltd. product name : BMPA] 0.43 g, toluene 59.21 g, and p-toluenesulfonic acid [manufactured by Tokyo Chemical Industry Co., Ltd.] 0.13 g were charged into a three-necked flask and mixed at 115 ° C. for 3 hours for esterification. The catalyst was removed by washing with water to obtain a toluene solution containing 30.0 wt% of thiol-modified silicone (A-3).

-Synthesis of dispersant (B-3) having silicone structure and dicarboxylic acid anhydride structure 51.70 g of toluene solution containing 30.0 wt% of thiol-modified silicone (A-3) and 5-norbornene 2,3-dicarboxylic acid 0.40 g of acid anhydride [manufactured by Tokyo Kasei Kogyo Co., Ltd.] was placed in a beaker and completely dissolved, and then the periphery was cooled with ice, and a spot UV irradiation device, Spot Cure SP-11 (manufactured by Ushio Inc.) was used. By using this, UV irradiation for 3 minutes was carried out to carry out the enethiol reaction to obtain a toluene solution containing 30.5 wt% of the dispersant (B-3).

-Production of silicone-treated zirconia (C-3) Zirconia [manufactured by Shin Nippon Denko Co., Ltd. product name: PCS60, primary particle diameter 15 nm to 25 nm] 5.0 g, and 30.5 wt% of the dispersant (B-3). Toluene solution 12.5 g, toluene 82.4955 g, catalyst [Kanto Chemical Co., Inc. product name: N-ethyldiisopropylamine] 0.02 g were used in a batch type Ready Mill RMB-04 [IMEX Co., Ltd.], A bead mill treatment was performed at a rotation speed of 2650 rpm for 10 minutes to obtain a toluene dispersion liquid containing 8.81 wt% of silicone-treated zirconia (C-3).

Preparation of Zirconia-Silicone Oil Dispersion 0.35 g of vinyl-terminated polydimethylsiloxane (Gelest product name: DMS-V21) and 4.0 g of the above-mentioned silicone-treated zirconia (C-3) toluene dispersion were mixed, and the solvent was removed. By carrying out the treatment, a silicone oil dispersion containing 50 wt% of silicone-treated zirconia was obtained.
The refractive index was measured using an Abbe refractometer 3L [manufactured by Shimadzu Corporation] to be 1.4510. (Table 1)

-Preparation of cured product of zirconia-silicone oil dispersion Vinyl-terminated polydimethylsiloxane (product name: Gelest, product name: DMS-V21) 0.10 g, methyl hydrogen silicone oil [product name: SH-1107, manufactured by Toray Dow Corning Co., Ltd.] ] 0.015g was mixed and the silicone compound (D-3) was obtained.
0.0012 g of platinum catalyst was mixed with 0.10 g of zirconia-silicone oil dispersion [vinyl-terminated polydimethylsiloxane (product name: Gelest, product name: DMS-V21), 2.46 g of a toluene solution of the above-mentioned silicone-treated zirconia (C-3)]. After performing the solvent removal treatment, the silicone compound (D-3) was mixed.
Then, it was applied on glass to a film thickness of 2 μm and heated at 150 ° C. for 2 hours to obtain a cured product. As a result of measuring the total light transmittance using an ultraviolet-visible spectrophotometer V-750 [manufactured by JASCO Corporation], the total light transmittance (380 nm to 780 nm) was 92.2%. (Table 1 and Figure 1)

<Example 4>
Synthesis of dispersant (B-4) having silicone structure and dicarboxylic acid anhydride structure 10.00 g of hydrogen silicone oil (Product name: MCR-H21 manufactured by Gelest) and 5-norbornene 2,3-dicarboxylic acid anhydride [Tokyo Kasei Kogyo Co., Ltd.] 0.36 g, toluene 24.29 g, platinum catalyst (Gelest product name: SIP6830.3) 0.50 g are charged into a three-necked flask and mixed at 60 ° C. for 3 hours, and hydro. I did a sill. As a result, a toluene solution containing 30.9 wt% of the dispersant (B-4) was obtained.

-Production of silicone-treated zirconia (C-4) 5.0 g of zirconia [manufactured by Shin Nippon Denko Co., Ltd .: PCS60, primary particle size 15 nm to 25 nm], 30.9 wt% of the dispersant (B-4) is contained. Toluene solution 12.5 g, toluene 82.4955 g, catalyst [Kanto Chemical Co., Inc. product name: N-ethyldiisopropylamine] 0.0045 g were used in a batch type Ready Mill RMB-04 [IMEX Co., Ltd.], After a bead mill treatment for 10 minutes at a rotation speed of 2650 rpm, ultrasonic treatment was performed to obtain a toluene dispersion liquid containing 8.86 wt% of silicone-treated zirconia (C-4).

-Preparation of zirconia-silicone oil dispersion 0.35 g of vinyl-terminated polydimethylsiloxane (Product name: Gelest manufactured by Gelest: DMS-V21) and 4.0 g of the above-mentioned silicone-treated zirconia (C-4) toluene dispersion were mixed and desolvated. By carrying out the treatment, a silicone oil dispersion containing 50 wt% of silicone-treated zirconia was obtained.
The refractive index measured using an Abbe refractometer 3L [manufactured by Shimadzu Corporation] was 1.4335. (Table 1)

-Preparation of cured product of zirconia-silicone oil dispersion Vinyl-terminated polydimethylsiloxane (product name: Gelest, product name: DMS-V21) 0.10 g, methyl hydrogen silicone oil [product name: SH-1107, manufactured by Toray Dow Corning Co., Ltd.] ] 0.015g was mixed and the silicone compound (D-4) was obtained.
0.0004 g of a platinum catalyst was mixed with 0.10 g of a zirconia-silicone oil dispersion [vinyl-terminated polydimethylsiloxane (product name: Gelest, product name: DMS-V21), 2.46 g of a toluene solution of the above-mentioned silicone-treated zirconia (C-4)]. After performing the solvent removal treatment, the silicone compound (D-4) was mixed.
Then, it was applied on glass to a film thickness of 2 μm and heated at 150 ° C. for 2 hours to obtain a cured product. The total light transmittance was measured using an ultraviolet-visible spectrophotometer V-750 [manufactured by JASCO Corporation], and as a result, the total light transmittance (380 nm to 780 nm) was 91.7%. (Table 1 and Figure 1)

<Comparative Example 1>
Preparation of untreated silicone zirconia (C-5) toluene dispersion Zirconia [manufactured by Shin Nippon Denko Co., Ltd. product name: PCS60, primary particle size 15 nm to 25 nm] 8.75 g, toluene 91.2455 g, catalyst [Kanto Chemical ( Co., Ltd. product name: N-ethyldiisopropylamine] 0.0045 g was subjected to bead mill treatment using a batch type ready mill RMB-04 [IMEX Co., Ltd.], and silicone untreated zirconia (C-5) was added to 8 A toluene dispersion containing 0.75 wt% was obtained.

-Preparation of zirconia-silicone oil dispersion: 0.35 g of vinyl-terminated polydimethylsiloxane (product name: Gelest manufactured by Gelest: DMS-V21) and 4.0 g of a toluene dispersion of the above-mentioned untreated silicone zirconia (C-5) were mixed and the mixture was removed. By performing the solvent treatment, a silicone oil dispersion containing 50 wt% of untreated silicone zirconia was obtained.
Abbe refractometer 3L [manufactured by Shimadzu Corporation] was used, but it was impossible to measure due to cloudiness. (Table 1)

Preparation of cured product of zirconia-silicone oil dispersion Vinyl-terminated polydimethylsiloxane (product name: Gelest, product name: DMS-V21) 0.10 g, methyl hydrogen silicone oil [product name: SH-1107, manufactured by Toray Dow Corning Co., Ltd.] ] 0.015g was mixed and the silicone compound (D-5) was obtained.
Zirconia-silicone oil dispersion [vinyl-terminated polydimethylsiloxane (made by Gelest, product name: DMS-V21) 0.10 g, silicone untreated zirconia (C-5) toluene solution 2.46 g] was mixed with platinum catalyst 0.0012 g. After performing the solvent removal treatment, the silicone compound (D-5) was mixed.
Then, it was applied on glass to a film thickness of 2 μm and heated at 150 ° C. for 2 hours to obtain a cured product. As a result of measuring the total light transmittance using an ultraviolet-visible spectrophotometer V-750 [manufactured by JASCO Corporation], the total light transmittance (380 nm to 780 nm) was 63.2%. (Table 1 and Figure 1)

<Comparative example 2>
-Refractive index measurement of silicone oil The refractive index of vinyl-terminated polydimethylsiloxane (product name: Gelest manufactured by Gelest: DMS-V21) was measured using an Abbe refractometer 3L [manufactured by Shimadzu Corporation], and the result was 1.430. It was (Table 1)

-Production of cured product of silicone oil Vinyl-terminated polydimethylsiloxane (Product name: DMS-V21 manufactured by Gelest) 0.20 g, methyl hydrogen silicone oil [Product name: SH-1107 manufactured by Toray Dow Corning Co., Ltd.] 0.015 g , 0.0001 g of platinum catalyst was mixed.
Then, it was applied on glass to a film thickness of 2 μm and heated at 150 ° C. for 2 hours to obtain a cured product. As a result of measuring the total light transmittance using an ultraviolet-visible spectrophotometer V-750 [manufactured by JASCO Corporation], the total light transmittance (380 nm to 780 nm) was 93.0%. (Table 1)

<Comparative example 3>
As a dispersant having a silicone structure and a dicarboxylic acid anhydride structure at both ends thereof, a carboxylic acid anhydride-modified silicone having both ends (manufactured by Shin-Etsu Silicone Co., Ltd., product name: X-22-168AS) was used. Similarly, a silicone-treated zirconia was prepared, and a zirconia-silicone oil mixture was prepared. In this zirconia-silicone oil mixture, the dispersion of zirconia was poor and the transmittance was apparently low.

Claims (6)

A thiol-modified silicone compound having one end or both ends modified with a monovalent group represented by the following formula (1).
[In the above formula (1), * ¹ represents the bonding position to the silicone compound. ]   A dispersant having a silicone structure and a dicarboxylic acid anhydride structure at one end of the silicone structure.   A silicone-treated zirconia surface-treated with the dispersant according to claim 2.   A zirconia-silicone oil dispersion obtained by dispersing the silicone-treated zirconia according to claim 3 in silicone oil.   A cured product obtained by curing the zirconia-silicone oil dispersion according to claim 4. A silicone LED encapsulant containing the cured product according to claim 5.