WO2010090280A1 - Transparent sealing material composition and optical semiconductor element - Google Patents

Abstract

Disclosed is a transparent sealing material composition containing: (A) an alkoxysilane-denatured polysiloxane obtained by causing (1) polysiloxane having a silanol group at both ends and represented by general formula (I) (in the formula, R¹ represents a methyl group or a phenyl group, the average number (m) of repeating units represents 5-500, and the R¹ can be the same or different), and (2) tetra-alkoxysilane partial condensate with an average number (n) of Si of 3-6, to undergo a dealcoholization reaction; and (B) a curing catalyst. Further disclosed is an optical semiconductor element obtained using said sealing material composition.

Description

Transparent encapsulant composition and optical semiconductor element

The present invention relates to a transparent encapsulant composition and an optical semiconductor element.

Patent Document 1 and Patent Document 2 describe an acid anhydride or cation as a curing agent in an alicyclic epoxy resin used for sealing an optical semiconductor chip or the like in the manufacture of an optical semiconductor element such as a light emitting diode (LED). A composition containing a polymerization catalyst is disclosed. A cured product obtained from the composition has good heat resistance, mechanical properties, electrical properties, and the like, and is excellent in transparency. However, in recent years, LEDs that emit light of short wavelengths such as blue light and ultraviolet light have been developed, and the durability is insufficient when the composition is used as a transparent sealing material for manufacturing such LEDs. Therefore, the occurrence of coloring and cracks due to deterioration of the cured product by heat and light has become a problem.

On the other hand, Patent Document 3 and Patent Document 4 disclose a composition containing a silicone resin having an alkenyl group such as a vinyl group and a silicone resin having a Si—H group in which a hydrogen atom is directly bonded to a silicon atom. . The composition is cured by a hydrosilylation reaction between an alkenyl group and a Si—H group. The cured product is excellent in transparency and light resistance, but is organic in the crosslinked structure of the cured product. Therefore, in applications such as LEDs with high luminous efficiency and high output, heat resistance is not sufficient.

JP 2003-277473 A JP 2003-176334 A JP 2004-359756 A JP 2004-221308 A

An object of the present invention is to use a transparent encapsulant composition that can be cured by heating, and that the resulting cured product can satisfy all of various properties such as transparency, heat resistance, and light resistance to short wavelength light, and the composition. Another object is to provide an optical semiconductor device obtained in this way.

The inventor has intensively studied to achieve the above-mentioned problems. As a result, transparent sealing containing a specific alkoxysilane-modified polysiloxane (A) and a curing catalyst (B) obtained by dealcoholizing a polysiloxane having silanol groups at both ends and a tetraalkoxysilane partial condensate The present inventors have found that the above problems can be achieved with the material composition, and have completed the present invention.

The present invention provides the following transparent encapsulant composition and optical semiconductor element.

1. (A) General formula (I)

（式中、Ｒ^１は、メチル基またはフェニル基を示し、平均繰り返し単位数ｍは、５～５００を示す。Ｒ^１同士は同一でも異なっていてもよい。）で表される両末端にシラノール基を有するポリシロキサン（１）と、Ｓｉの平均個数ｎが３～６のテトラアルコキシシラン部分縮合物（２）とを脱アルコール反応させて得られるアルコキシシラン変性ポリシロキサン、及び
（Ｂ）硬化触媒を含有する透明封止材組成物。

(Wherein R ¹ represents a methyl group or a phenyl group, and the average repeating unit number m represents 5 to 500. R ¹ may be the same or different.) An alkoxysilane-modified polysiloxane obtained by dealcoholizing a polysiloxane (1) having a group and a tetraalkoxysilane partial condensate (2) having an average number of Si of 3 to 6; and (B) a curing catalyst. The transparent sealing material composition containing this.

2. The tetraalkoxysilane partial condensate (2) has the general formula (II)

〔式中、Ｒ^２は、メチル基、エチル基又は一般式(III)

[In the formula, R ² represents a methyl group, an ethyl group or a general formula (III)

（ここで、Ｒ^３はメチル基又はエチル基を示す。Ｒ^３同士は同一でも異なっていてもよい。）で表される基を示す。ｐ及びqはいずれも０以上の整数であり、Ｓｉの平均個数ｎは３～６である。Ｒ^２同士は同一でも異なっていてもよい。〕で表されるものである上記項１に記載の透明封止材組成物。

(Here, R ³ represents a methyl group or an ethyl group. R ³ may be the same or different.) p and q are both integers of 0 or more, and the average number n of Si is 3-6. R ² may be the same or different. ] The transparent sealing material composition of said claim | item 1 which is represented by these.

3. The alkoxysilane-modified polysiloxane (A) reacts the polysiloxane (1) and the tetraalkoxysilane partial condensate (2) in a molar ratio of the former: the latter = 1: 1.5 to 1: 2.5. Item 2. The transparent encapsulant composition according to Item 1, which is a reaction product obtained in this way.

4. 2. The transparent sealing according to item 1, wherein the alkoxysilane-modified polysiloxane (A) is such that at least 75% of the terminal silanol groups of the polysiloxane (1) are alkoxysilane-modified with a tetraalkoxysilane partial condensate (2). Material composition.

5. Item 2. The transparent encapsulant composition according to Item 1, wherein the curing catalyst (B) is an organometallic catalyst.

6. Item 6. The transparent encapsulant composition according to Item 5, wherein the organometallic catalyst is an organic acid metal salt.

7. Item 2. The transparent sealing material composition according to Item 1, wherein the amount of the curing catalyst (B) is 0.1 to 5 parts by weight with respect to 100 parts by weight of the alkoxysilane-modified polysiloxane (A).

8. Further, (C) in the above general formula (I), the polysiloxane having a silanol group at both ends having an average repeating unit number m of 50 to 1500 and a number average molecular weight of 5000 to 100,000 is The transparent sealing material composition as described.

9. Hardened | cured material obtained by heat-hardening the transparent sealing material composition of said claim | item 1.

10. An optical semiconductor element formed by sealing an optical semiconductor using the transparent sealing material composition according to Item 1.

11. Item 11. The optical semiconductor device according to Item 10, wherein the optical semiconductor is a light emitting diode chip.

According to the present invention, the following remarkable effects can be obtained.

(1) The transparent sealing material composition of the present invention can be easily cured by heating. In addition, the cured product of the composition has improved properties such as transparency; heat resistance; light resistance to light including short wavelength light such as blue light and ultraviolet light. Moreover, it is excellent in adhesiveness.

(2) Therefore, the transparent encapsulant composition of the present invention is extremely useful as a transparent encapsulant used when producing an optical semiconductor element such as a light emitting diode (LED). In addition, the optical semiconductor element obtained by using the composition has sufficient durability, is substantially free from deterioration of a cured product due to heat and light, and has heat resistance even in applications such as high-power LEDs. Is sufficient and reliable.

Transparent sealing material composition The transparent sealing material composition of the present invention is a silicone resin composition containing an alkoxysilane-modified polysiloxane (A) and a curing catalyst (B).

Alkoxysilane-modified polysiloxane (A)
The alkoxysilane-modified polysiloxane (A) used in the present invention includes a polysiloxane (1) having silanol groups at both ends represented by the following general formula (I), and a tetraalkoxy having an average number of Si of 3 to 6 It can be obtained by subjecting the silane partial condensate (2) to dealcoholization reaction.

General formula

In the general formula (I), R ¹ represents a methyl group or a phenyl group, and a plurality of R ¹ may be the same or different. The average repeating unit number m is 5 to 500.

The polysiloxane (1) having a silanol group at both ends represented by the general formula (I) has a silanol group at both ends of the main chain, and R ¹ is selected from a methyl group and a phenyl group. Silicone oil.

Examples of the main chain structure of the polysiloxane (1) include polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane. As the polysiloxane (1), those having two or more kinds of main chain structures may be mixed and used. Polysiloxane (1) has a main chain structure that does not contain organic covalent bonds (C—C, C—O, Si—C, etc.) and is composed of highly heat-resistant siloxane bonds (Si—O—Si). It is characterized by having a structure in which silanol groups (Si—OH) are directly bonded to both ends of the main chain. Common commercially available silicone oils contain polyether, polycarbonate, etc. in the main chain structure; organic functional groups such as aminopropyl groups, glycidoxypropyl groups, carbitol groups, (meth) acrylic groups at the molecular ends Many of them have a group, but use of these silicone oils containing an organic covalent bond is not preferable because the heat resistance of the cured product is lowered.

The polysiloxane (1) has a number average molecular weight measured by gel permeation chromatography (GPC) of about 500 to 30,000, preferably about 800 to 10,000. The average number of repeating units m in the general formula (I) is About 5 to 500, preferably about 10 to 200 can be used. Examples of GPC measuring instruments include “SC8010” (trade name, manufactured by Tosoh Corporation). The molecular weight of the polysiloxane (1) mainly determines the hardness of the cured product and the viscosity of the transparent sealing material composition. By setting the number average molecular weight of the polysiloxane (1) to 500 or more, it is preferable because the hardness of the cured product can be appropriately maintained, and the occurrence of cracks and the like can be suppressed. It is preferable because the viscosity can be maintained moderately and handling becomes easy.

The tetraalkoxysilane partial condensate (2) is typically represented by the following general formula (II).

General formula

In the general formula (II), R ² represents a methyl group, an ethyl group, or a general formula

（ここで、Ｒ^３はメチル基又はエチル基を示す。複数のＲ^３同士は同一であっても異なっていても構わない。）で表される基を示す。ｐ及びqはいずれも０以上の整数であり、Ｓｉの平均個数ｎは３～６である。複数のＲ^２同士は同一であっても異なっていても構わない。

(Here, R ³ represents a methyl group or an ethyl group. A plurality of R ³ may be the same or different from each other.). p and q are both integers of 0 or more, and the average number n of Si is 3-6. A plurality of R ² may be the same or different.

The tetraalkoxysilane partial condensate (2) represented by the general formula (II) is a product obtained by partially hydrolyzing and condensing hydrolyzable tetraalkoxysilane. Here, R ² represents a methyl group, an ethyl group or a group represented by the general formula (III). When the group has the group represented by the general formula (III), the partial condensate (2) has a branched structure. This is the case. In the partial condensate (2), when R ² and R ³ constituting the alkoxy group have a substituent other than a methyl group or an ethyl group, it is difficult to cure the transparent encapsulant composition. Therefore, it is not preferable. On the other hand, when R ² and / or R ³ is a silanol group, the viscosity stability of the composition is lowered.

Specific examples of the hydrolyzable tetraalkoxysilane include tetramethoxysilane and tetraethoxysilane. Among these, it is most preferable to use tetraethoxysilane from the viewpoint of viscosity stability of the transparent sealing material composition and ease of curing. On the other hand, as hydrolyzable alkoxysilanes, trialkoxysilanes such as methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, phenyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, Use of dialkoxysilanes such as diethyldimethoxysilane and diethyldiethoxysilane is not preferable because the heat resistance of the cured product is deteriorated.

In the tetraalkoxysilane partial condensate (2) of the general formula (II), water is usually subjected to a hydrolysis reaction in the range of about 0.125 to 0.33 equivalent to 1 equivalent of the alkoxy group of the hydrolyzable tetraalkoxysilane. Obtained by further condensation.

In the general formula (II), the average number n of Si is 3 or more and 6 or less. If the average number n of Si is less than 3, the proportion of hydrolyzable tetraalkoxysilane that is distilled out of the system unreacted during the dealcoholization reaction is increased, and the heat resistance of the cured product is lowered, which is not preferable. On the other hand, if the average number n of Si exceeds 6, the compatibility with the polysiloxane (1) is lowered, so that the production of the alkoxysilane-modified polysiloxane (A) tends to be difficult.

The alkoxysilane-modified polysiloxane (A) is produced by dealcoholizing the polysiloxane (1) and the tetraalkoxysilane partial condensate (2). In this reaction, the use ratio of the polysiloxane (1) and the alkoxysilane partial condensate (2) is not particularly limited, but [number of moles of the alkoxysilane partial condensate (2)] / [mol of polysiloxane (1). The molar ratio represented by [number] is preferably in the range of about 1.5 to 2.5, and more preferably in the range of about 1.6 to 2.0. If the molar ratio is less than 1.5, gelation tends to occur during the dealcoholization reaction. If it exceeds 2.5, the unreacted alkoxysilane partial condensate (2) that does not react with the polysiloxane (1) increases. Therefore, neither is preferable.

Specifically, the alkoxysilane-modified polysiloxane (A) is prepared by, for example, charging the polysiloxane (1) and the tetraalkoxysilane partial condensate (2) at the above-mentioned use ratio and heating to distill off the alcohol produced. Carry out the dealcoholization reaction. The reaction temperature is not particularly limited, but is usually preferably about 90 to 170 ° C, more preferably about 110 to 150 ° C. The reaction time is usually preferably about 1 to 15 hours.

In addition, in the above dealcoholization reaction, a known transesterification catalyst can be used to promote the reaction. Examples of the catalyst include lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, barium, strontium, zinc, aluminum, titanium, cobalt, germanium, tin, lead, antimony, arsenic, cerium, boron, cadmium, manganese. Metals such as oxides, organic acid salts, halides, and alkoxides of these metals. Among these, organic tin, organic acid tin, and the like are particularly preferable, and specifically, dibutyltin dilaurate is effective.

In the alkoxysilane-modified polysiloxane (A) used in the present invention, it is preferable that at least 75% of the terminal silanol groups of the polysiloxane (1) to be used are modified with alkoxysilane. When the modification rate is less than 75%, the unreacted tetraalkoxysilane partial condensate (2) increases, and there is a tendency to cause cracks due to volatilization during curing. On the other hand, the alkoxysilane-modified polysiloxane (A) may contain the unreacted tetraalkoxysilane partial condensate (2) as long as the amount is small, and the unreacted alkoxysilane partial condensate (2) When the transparent sealing material composition of the present invention is cured, it is cured by a sol-gel reaction together with the alkoxysilane-modified polysiloxane (A).

The alkoxysilane-modified polysiloxane (A) is a block polymer having polyalkoxysilane segments derived from the alkoxysilane partial condensate (2) on both terminal sides of the segments derived from the polysiloxane (1). The alkoxysilyl groups located at both ends undergo a sol-gel reaction in the presence of the curing catalyst (B) to form a silica (SiO ₂ ) site, which is a higher network structure of siloxane bonds, and is cured. Further, by concentrating the alkoxysilyl groups at both ends, the reactivity of the alkoxysilyl group in the molecule or between the molecules is improved, and the unreacted alkoxysilyl group is prevented from remaining in the cured product. Moreover, the formed silica part is connected with the covalent bond by the polysiloxane (1) segment. The polysiloxane segment does not contain a reactive group in the segment, relieves stress generated during curing, suppresses foaming, and further imparts toughness and flexibility to the cured product.

Curing catalyst (B)
The curing catalyst (B) used in the transparent sealing material composition of the present invention is a component required for curing reaction of alkoxysilyl groups located at both ends of the alkoxysilane-modified polysiloxane (A). As the curing catalyst (B), an organometallic catalyst is preferably used because it is excellent in the stability of the transparent sealing material composition, the hardness of the resulting cured product, non-yellowing, and the like.

Examples of the organometallic catalyst include those containing atoms such as zinc, aluminum, titanium, tin, bismuth and cobalt, and preferably those containing atoms such as zinc, aluminum, bismuth and tin. . Specific examples include organic acid metal salts such as organic acid zinc, organic acid tin, and organic acid bismuth; Lewis acid catalysts; organic metal compounds such as organic aluminum compounds and organic titanium compounds. Among these, preferred are Is an organic acid metal salt. More specifically, zinc octylate, zinc benzoate, zinc p-tert-butylbenzoate, zinc laurate, zinc stearate, aluminum chloride, aluminum perchlorate, aluminum phosphate, aluminum triisopropoxide, aluminum Acetyl acetonate, aluminum butoxybisethyl acetoacetate, tetrabutyl titanate, tetraisopropyl titanate, tin octylate, bismuth octylate, cobalt naphthenate, tin naphthenate, etc., preferably tin octylate, bismuth octylate, Zinc octylate. These may be used individually by 1 type, or may use 2 or more types together.

The blending amount of the curing catalyst (B) is usually about 0.1 to 5 parts by weight with respect to 100 parts by weight of the alkoxysilane-modified polysiloxane (A). Curing is facilitated by setting the content to 0.1 parts by weight or more, and it is preferable to use 5 parts by weight or less because the stability of the transparent sealing material composition is improved.

Optional component In addition to the alkoxysilane-modified polysiloxane (A) and the curing catalyst (B) described above, the composition of the present invention may have an average number of repeating units m in the general formula (I) as necessary. The polysiloxane (C) having silanol groups at both ends having a number average molecular weight of about 5,000 to 100,000. By blending the polysiloxane (C) having silanol groups at both ends, the advantage that the generation of voids in the cured product can be suppressed can be obtained. When the polysiloxane (C) is blended, the blending amount is not particularly limited, but it is usually preferably about 1 to 20000 parts by weight with respect to 100 parts by weight of the alkoxysilane-modified polysiloxane (A). More preferably, it is about 10 to 2000 parts by weight.

Even when a polysiloxane (C) having a number average molecular weight of about 5,000 to 100,000 and having silanol groups at both ends is blended, a part of the silanol groups at the molecular ends is derived from the alkoxysilane partial condensate (2) ( Bonding with the SiO ₂ ) structure forms a crosslinked structure that does not contain organic covalent bonds.

In the composition of the present invention, other optional components other than polysiloxane (C) can be blended as long as the effects and effects of the present invention are not impaired. Other optional components include, for example, inorganic fillers, inorganic phosphors, anti-aging agents, radical inhibitors, ultraviolet absorbers, adhesion improvers, flame retardants, surfactants, storage stability improvers, ozone deterioration inhibitors, Light stabilizer, Thickener, Plasticizer, Coupling agent, Antioxidant, Thermal stabilizer, Conductivity imparting agent, Antistatic agent, Radiation shielding agent, Nucleating agent, Phosphorus peroxide decomposition agent, Lubricant, Pigment , Metal deactivators, physical property modifiers, organic solvents and the like. These optional components may be used alone or in combination of two or more.

By blending an inorganic filler as the above optional component, the refractive index of the obtained cured product and the fluidity of the composition can be adjusted to an appropriate range, or the strength of the cured product of the composition can be improved. The inorganic filler is not particularly limited, but is preferably in the form of fine particles that do not deteriorate the optical properties, such as alumina, aluminum hydroxide, fused silica, crystalline silica, ultrafine amorphous silica, hydrophobic ultrafine silica, talc. , Calcium carbonate, barium sulfate and the like.

Preparation of transparent sealing material composition The transparent sealing material composition of the present invention is prepared by mixing the alkoxysilane-modified polysiloxane (A), the curing catalyst (B) and optional components contained as necessary by a known method. Can be prepared. Specifically, for example, an alkoxysilane-modified polysiloxane (A), a curing catalyst (B), and the above-mentioned optional components are usually combined with a commercially available stirrer (for example, “THINKY CONDITIONING MIXER” (trade name, manufactured by Shinky Corp.). ) Etc.) and mixing uniformly for about 1 to 5 minutes, the composition of the present invention can be prepared.

Curing of transparent sealing material composition The transparent sealing material composition of the present invention can be cured, for example, by heating at about 50 to 250 ° C. for about 0.5 to 24 hours. During curing, alcohol is generated during curing, and therefore it is preferable to perform step cure in a temperature range of about 80 to 200 ° C. Step cure can be performed through two or more stages, preferably through the following three stages. First, the transparent sealing material composition of the present invention is usually cured at a low temperature of about 80 to 120 ° C. The curing time is not particularly limited, but may usually be in the range of about 0.5 to 2 hours. Next, the low-temperature cured product is usually heat-cured at about 125 to 175 ° C. The curing time is not particularly limited, but may usually be in the range of about 0.5 to 2 hours. Finally, the cured product is cured by heating at about 180 to 200 ° C. The curing time is not particularly limited, but may usually be in the range of about 1 to 10 hours. More specifically, for example, it is preferable to cure the composition at 80 ° C. for 1 hour at low temperature, then heat cure at 150 ° C. for 1 hour, and further heat cure at 200 ° C. for 8 hours. The cured product obtained by step cure after these steps is sufficiently cured, and there is almost no generation of bubbles. Furthermore, since a colorless and transparent cured product can be easily obtained by step cure, it is useful as a sealing material for optical semiconductors.

A cured product obtained by heating and curing the transparent sealing material composition of the present invention has a siloxane bond (Si—O—Si) having a main chain structure derived from polysiloxane (1) and an alkoxysilane partial condensate having a crosslinking site ( It has a silica (SiO ₂ ) structure derived from 2) and does not contain an organic covalent bond, so it is difficult to be thermally decomposed and is useful as a sealing material for high-output optical semiconductors that require particularly high heat resistance.

Use of transparent encapsulant composition The transparent encapsulant composition of the present invention is excellent in transparency, heat resistance, light resistance, adhesiveness, and the like, and thus an optical semiconductor element such as a light emitting element, a light receiving element, a photoelectric conversion element; It can be suitably used as a transparent sealing material used when manufacturing optical transmission-related parts and the like.

The transparent sealing material composition of the present invention can be particularly suitably used for the production of a light emitting diode (LED) which is a light emitting element. Usually, a light emitting diode can be manufactured by sealing a light emitting diode chip with the transparent sealing material composition of this invention.

The LED chip is not particularly limited, and various types of LED chips that can be used for LEDs can be used. For example, a material produced by laminating a semiconductor material such as a nitride compound semiconductor on a sapphire substrate.

The emission wavelength of the LED is not particularly limited from the ultraviolet region to the infrared region, but the effect of the present invention is particularly remarkable when the main emission peak wavelength is 550 nm or less. One type of LED may be used to emit monochromatic light, or a plurality of LEDs may be used to emit monochromatic or multicolored light.

Various known methods can be applied as a method for sealing the wrinkles. For example, a liquid transparent sealing material composition may be injected into a cup, cavity, package recess, or the like in which an LED chip or a lead electrode is arranged at the bottom using a dispenser and cured by heating, or may be solid The transparent sealing material composition may be flowed by heating or the like, and similarly injected into a cup or the like and further heated to be cured. The cup and the like can be prepared using various materials, such as polycarbonate resin, polyphenylene sulfide resin, epoxy resin, acrylic resin, silicone resin, ABS resin, polybutylene terephthalate resin, polyphthalamide resin, and the like. be able to. Also, a method of injecting a transparent sealing material composition into a mold mold in advance and immersing a lead frame or the like on which the LED chip is fixed and then curing it can be applied. The sealing layer made of the transparent sealing material composition may be molded and cured in the frame by injection with a dispenser, transfer molding, injection molding or the like. The transparent sealing material composition may be simply dropped or coated on the LED chip and cured. The transparent encapsulant composition can be molded and cured by stencil printing, screen printing, or application through a mask on the LED chip. A transparent sealing material composition partially cured or cured in advance in a plate shape or a lens shape may be fixed on the LED chip.

The shape of the light emitting diode to which the transparent sealing material composition of the present invention is applied is not particularly limited, and can be appropriately selected according to the application. Specifically, a shell type and a surface mount type used in lighting equipment and the like can be mentioned.

The transparent sealing material composition of the present invention can also be used as a die bond agent for fixing an optical semiconductor such as an LED chip to a lead terminal or a package. Furthermore, the cured product obtained by heating and curing the transparent sealing material composition of the present invention can be used as a passivation film on a light-emitting element; a molded body such as a package substrate.

Hereinafter, the present invention will be specifically described with reference to synthesis examples, examples and comparative examples. However, the present invention is not limited to these examples. In each example, parts and% are based on weight unless otherwise specified.

Synthesis example 1
Production of alkoxysilane-modified polysiloxane (A-1) Polysiloxane (1) with silanols at both ends (Momotive Performance Materials Japan Co., Ltd.) was added to a reactor equipped with a stirrer, cooling pipe, thermometer, and nitrogen introduction pipe. ) trade name "YF3800", number average molecular weight of 6000, in the general formula (I), R ¹ is a methyl group, m = 80 ones) 1900 parts of tetraethoxysilane partial condensate (2) (formula ( In II), 471.83 parts of R ² and R ³ constituting the alkoxy group were ethyl groups and the average number of Si was n = 5) and heated. When the temperature reached 140 ° C., 0.48 part of dibutyltin dilaurate was added as a catalyst and reacted at 140 ° C. for 6 hours to obtain an alkoxysilane-modified polysiloxane (A-1). In addition, ([number of moles of alkoxysilane partial condensate (2)] / [number of moles of polysiloxane (1)]) = 2.0 at the time of preparation. It was confirmed that the amount of ethanol distilled off from the mass difference before and after the reaction was 32.2 parts.

Synthesis example 2
Production of alkoxysilane-modified polysiloxane (A-2) In the same reactor as used in Example 1, 1000 parts of polysiloxane (1) of both-end silanols used in Example 1 and tetramethoxysilane partial condensate (2) 155.1 parts (in general formula (II) where R ² and R ³ constituting an alkoxy group are methyl groups and Si has an average number n = 4) were charged and heated. When the temperature reached 120 ° C., 0.23 part of dibutyltin dilaurate was added as a catalyst and reacted at 120 ° C. for 3.5 hours to obtain alkoxysilane-modified polysiloxane (A-2). In addition, ([number of moles of alkoxysilane partial condensate (2)] / [number of moles of polysiloxane (1)]) = 2.0 at the time of preparation. It was confirmed that the amount of methanol distilled off from the mass difference before and after the reaction was 10.7 parts.

Synthesis example 3
Production of alkoxysilane-modified polysiloxane (A-3) In the same reaction apparatus as used in Example 1, polysiloxane (1) of both ends silanol (made by Momentive Performance Materials Japan Co., Ltd., trade name “ XF3905 ", number average molecular weight 20000, in general formula (I), R ¹ is methyl group, m = 270, 2150 parts and tetraethoxysilane partial condensate (2) (in general formula (II), alkoxy group 160.18 parts of R ² and R ³ constituting the ethyl group and Si having an average number n = 5) were charged and heated. When the temperature reached 140 ° C., 0.12 part of dibutyltin dilaurate was added as a catalyst and reacted at 140 ° C. for 8 hours to obtain alkoxysilane-modified polysiloxane (A-3). In addition, ([number of moles of alkoxysilane partial condensate (2)] / [number of moles of polysiloxane (1)]) = 2.0 at the time of preparation. It was confirmed that the amount of ethanol distilled off from the mass difference before and after the reaction was 10.85 parts.

Synthesis example 4
Production of alkoxysilane-modified polysiloxane (A-4) A reaction apparatus similar to that used in Example 1 was prepared by using polysiloxane (1) having both ends silanol (number average molecular weight 6000, R ¹ is phenyl in the general formula (I) 1900 parts of a group, m = 30) and a tetraethoxysilane partial condensate (2) (in formula (II), R ² and R ³ constituting an alkoxy group are ethyl groups, and the average number of Si is n = 5) 1) 471.83 parts were charged and heated. When the temperature reached 140 ° C., 0.48 part of dibutyltin dilaurate was added as a catalyst and reacted at 140 ° C. for 6 hours to obtain alkoxysilane-modified polysiloxane (A-4). In addition, ([number of moles of alkoxysilane partial condensate (2)] / [number of moles of polysiloxane (1)]) = 2.0 at the time of preparation. It was confirmed that the amount of ethanol distilled off from the mass difference before and after the reaction was 32.1 parts.

Synthesis example 5
Production of alkoxysilane-modified polysiloxane (A-5) A reaction apparatus similar to that used in Example 1 was charged with polysiloxane (1) having both ends silanol (number average molecular weight 6000, ^one of R ¹ in general formula (I)). Is a methyl group, the other is a phenyl group, and m = 40) 1900 parts and a tetraethoxysilane partial condensate (2) (in formula (II), R ² and R ³ constituting the alkoxy group are ethyl groups, 471.83 parts (with an average number of Si n = 5) were charged and heated. When the temperature reached 140 ° C., 0.48 part of dibutyltin dilaurate was added as a catalyst, and the mixture was allowed to react at 140 ° C. for 6 hours to obtain an alkoxysilane-modified polysiloxane (A-5). In addition, ([number of moles of alkoxysilane partial condensate (2)] / [number of moles of polysiloxane (1)]) = 2.0 at the time of preparation. It was confirmed that the amount of ethanol distilled off from the mass difference before and after the reaction was 32.1 parts.

Examples 1-6
The alkoxysilane-modified polysiloxanes (A-1) to (A-5) obtained in Synthesis Examples 1 to 5 were blended with the curing catalyst (B) shown in Table 1 in the proportions shown in Table 1, Each transparent sealing material composition of the invention was obtained.

Table 1 shows the component composition of each transparent sealing material composition.

Example 7
To 100 parts of the alkoxysilane-modified polysiloxane (A-1) obtained in Synthesis Example 1, polysiloxane (C) having both ends silanol (number average molecular weight 70000, in general formula (I), R ¹ is a methyl group, m = 1000) 100 parts and 0.5 parts of tin octylate as a curing catalyst (B) were blended to obtain a transparent encapsulant composition of the present invention.

Example 8
In 100 parts of the alkoxysilane-modified polysiloxane (A-1) obtained in Synthesis Example 5, polysiloxane (C) having both ends silanol (number average molecular weight 70000, in the general formula (I), ^one of R ¹ is a methyl group The other was a phenyl group, m = 500) 100 parts and 0.5 parts of tin octylate as a curing catalyst (B) were blended to obtain the transparent sealing material composition of the present invention.

Example 9
To 100 parts of the alkoxysilane-modified polysiloxane (A-1) obtained in Synthesis Example 1, polysiloxane (C) having both ends silanol (number average molecular weight 70000, in general formula (I), R ¹ is a methyl group, m = 1000) 100 parts and 1.0 part of bismuth octylate as the curing catalyst (B) were blended to obtain the transparent sealing material composition of the present invention.

Comparative Example 1
100 parts of hydrogenated bisphenol A type epoxy resin (trade name “Epoquito YX8000”, manufactured by Japan Epoxy Resins Co., Ltd.), methylhexahydrophthalic anhydride (trade name “Rekajit MH-700”, manufactured by Shin Nippon Rika Co., Ltd.) ) 80 parts was blended to obtain a comparative transparent encapsulant composition.

Comparative Example 2
100 parts of epoxy-modified polydimethylsiloxane (trade name “KF101”, manufactured by Shin-Etsu Chemical Co., Ltd.) and BF ₃ · Et ₂ O (BF ₃ ethyl etherate complex, manufactured by Tokyo Chemical Industry Co., Ltd.) as a cationic polymerization catalyst ) 0.05 part was blended to obtain a comparative transparent encapsulant composition.

Comparative Example 3
100 parts of methacryl-modified polydimethylsiloxane (trade name “X-22-164”, manufactured by Shin-Etsu Chemical Co., Ltd.) is added to BF ₃ • Et ₂ O (BF ₃ ethyl etherate complex, Tokyo Chemical Industry Co., Ltd.), which is a cationic polymerization catalyst. A comparative transparent sealing material composition was obtained by blending 0.05 part).

Next, each performance of adhesiveness, transparency, UV resistance, and heat resistance of each of the transparent sealing material compositions obtained in Examples and Comparative Examples was evaluated. The evaluation method is as follows.

Each adhesive composition was applied to a glass substrate by dipping, followed by step curing at 80 ° C. for 1 hour, then at 150 ° C. for 1 hour, and further at 200 ° C. for 1 hour to obtain a thickness of 2 on the glass substrate. A cured product of ˜3 μm was formed. Next, the adhesiveness of the cured product to the glass substrate was evaluated by a galvanic cellophane tape peeling test (JIS K-5400). Evaluation was shown by the number of remaining grids per 100 grids.

Each transparency composition was applied to a glass substrate by dipping, followed by step curing at 80 ° C. for 1 hour, then at 150 ° C. for 1 hour, and further at 200 ° C. for 1 hour to obtain a thickness of 2 on the glass substrate. A cured product of ˜3 μm was formed. The transparency of the cured product was visually observed and evaluated according to the following criteria.
A: Colorless and highly transparent.
B: Discoloration such as yellowing is observed.

1 g of each composition is dropped onto a UV-resistant glass substrate with a dropper, and a step cure is performed at 80 ° C. for 1 hour, then at 150 ° C. for 1 hour, and further at 200 ° C. for 1 hour to form a cured product on the glass substrate. I let you. The cured product was subjected to UV irradiation (30 mW, wavelength 295 to 450 nm) for 24 hours using a UV irradiation apparatus (trade name “I Super UV Tester SUV-F11”, manufactured by Iwasaki Electric Co., Ltd.). The surface of the cured product after UV irradiation was visually observed and evaluated according to the following criteria.
A: No discoloration is observed on the surface of the cured product.
B: Discoloration such as yellowing is observed.
C: Deterioration such as marked yellowing is observed.

Each heat-resistant composition is put into a mold coated with polytetrafluoroethylene, and step cured at 80 ° C. for 1 hour, then at 150 ° C. for 1 hour, and further at 200 ° C. for 1 hour, and a cured film having a thickness of 500 μm It was created. This cured film was put in an oven at 250 ° C., and the surface after 500 hours was visually observed and evaluated according to the following criteria.
A: No discoloration is observed on the surface of the cured product.
B: Discoloration such as yellowing is observed.
C: Deterioration such as marked yellowing is observed.

The performance evaluation results are shown in Table 2 below.

Since the transparent encapsulant composition of the present invention is excellent in transparency, heat resistance, light resistance, adhesiveness, etc., it manufactures optical semiconductor elements such as light emitting elements, light receiving elements, photoelectric conversion elements; It can be used as a transparent sealing material or the like used in the process, or as a die bond agent for fixing an optical semiconductor such as an LED chip to a lead terminal or a package. Moreover, the hardened | cured material obtained by heat-curing the transparent sealing material composition of this invention can be utilized as molded objects, such as a passivation film on a light emitting element; a package board | substrate.

Claims (11)

(A) General formula (I)

(Wherein R ¹ represents a methyl group or a phenyl group, and the average repeating unit number m represents 5 to 500. R ¹ may be the same or different.) An alkoxysilane-modified polysiloxane obtained by dealcoholizing a polysiloxane (1) having a group and a tetraalkoxysilane partial condensate (2) having an average number of Si of 3 to 6; and (B) a curing catalyst. The transparent sealing material composition containing this. The tetraalkoxysilane partial condensate (2) has the general formula (II)

[In the formula, R ² represents a methyl group, an ethyl group or a general formula (III)

(Here, R ³ represents a methyl group or an ethyl group. R ³ may be the same or different.) p and q are both integers of 0 or more, and the average number n of Si is 3-6. R ² may be the same or different. The transparent sealing material composition according to claim 1, which is represented by: The alkoxysilane-modified polysiloxane (A) reacts the polysiloxane (1) and the tetraalkoxysilane partial condensate (2) in a molar ratio of the former: the latter = 1: 1.5 to 1: 2.5. The transparent sealing material composition according to claim 1, which is a reaction product obtained by the step. The transparent sealing according to claim 1, wherein the alkoxysilane-modified polysiloxane (A) has at least 75% of the terminal silanol groups of the polysiloxane (1) modified with an alkoxysilane by a tetraalkoxysilane partial condensate (2). Material composition. The transparent encapsulant composition according to claim 1, wherein the curing catalyst (B) is an organometallic catalyst. The transparent encapsulant composition according to claim 5, wherein the organometallic catalyst is an organic acid metal salt. The transparent encapsulant composition according to claim 1, wherein the compounding amount of the curing catalyst (B) is 0.1 to 5 parts by weight with respect to 100 parts by weight of the alkoxysilane-modified polysiloxane (A). Furthermore, (C) in the general formula (I), the polysiloxane having silanol groups at both ends having an average repeating unit number m of 50 to 1500 and a number average molecular weight of 5000 to 100,000 is contained. The transparent sealing material composition as described. Hardened | cured material obtained by heat-curing the transparent sealing material composition of Claim 1. An optical semiconductor element formed by sealing an optical semiconductor using the transparent sealing material composition according to claim 1. The optical semiconductor element according to claim 10, wherein the optical semiconductor is a light emitting diode chip.