JP6296348B2 - Composition for transparent encapsulant, cured product, transparent encapsulant and light emitting diode - Google Patents

Description

  The present invention relates to a composition for transparent encapsulant, a cured product obtained from the composition, a transparent encapsulant made of the cured product, and a light emitting diode including the encapsulant.

  Conventionally, a composition containing an alicyclic epoxy resin and an acid anhydride has been used as a transparent sealing material for a semiconductor light emitting device typified by a light emitting diode (LED) (see Patent Documents 1 and 2). . However, a cured product obtained from the composition is easily deteriorated by heat or light, and may be colored or cracked when used as a sealing material for an LED that emits short wavelength light such as ultraviolet rays.

  On the other hand, a silicone-based resin composition is also used as a composition for a transparent sealing material of a semiconductor light emitting device. For example, a silicone polymer having a multiple bond such as a vinyl group and a silicone polymer having a SiH group are used. Compositions containing are known (see Patent Documents 3 and 4). However, the cured product of the composition is insufficient in terms of heat resistance and light resistance, such as deterioration in transparency and weight loss when it is heated for a long time or exposed to ultraviolet rays.

  In addition, as the silicone-based resin composition, a linear organopolysiloxane compound having two silanol groups in one molecule and a siloxane compound having three or more alkoxy groups or silanol groups in one molecule And a silicone composition containing a condensation catalyst (see Patent Document 5), a polysiloxane having silanol groups at both ends, and a tetraalkoxysilane partial condensate having an average number n of Si of 3 to 6 A composition (see Patent Document 6) in which a curing catalyst is blended with an alkoxysilane-modified polysiloxane obtained by dealcoholization reaction is known. However, the cured products of these compositions are insufficient in terms of heat resistance and light resistance, such as a decrease in transparency and a decrease in weight when subjected to heat for a long time or exposure to ultraviolet rays.

JP 2003-277473 A JP 2003-176334 A JP 2004-359756 A JP 2004-221308 A JP 2008-274272 A International Publication WO20120090280

  The present invention relates to a composition for transparent encapsulant that gives a cured product having good transparency, heat resistance, light resistance, etc., a cured product obtained from the composition, a transparent encapsulant comprising the cured product, and the transparent It is an object of the present invention to provide a light-emitting diode sealed with a sealing material.

  The inventor of the present invention is inferior in heat resistance and light resistance of the thermosets described in Patent Documents 3 and 4 because the cured product has an organic covalent bond (C—C, C—O, etc.) as a crosslinked structure. I thought it was because this part was vulnerable to heat and light.

  In addition, the inventor of the present invention is that the cured products described in Patent Documents 5 and 6 are inferior in heat resistance and light resistance because a metal compound such as dibutyltin dilaurate which is a condensation catalyst (curing catalyst) remains in the cured product. It was thought that this was due to the absorption and activation of ultraviolet light and heat to decompose the silicone polymer structure.

  Therefore, the present inventor has repeatedly studied from both the main agent and the curing catalyst, uses a specific polysiloxane and alkoxysilane condensate as the main agent, and uses a predetermined volatile amine as the curing catalyst instead of the metal catalyst. As a result, it was found that a composition for transparent encapsulating material capable of solving the above problems was obtained, and the present invention was completed.

  That is, the present invention provides a polysiloxane (A) having silanol groups at both ends represented by the following general formula (1), a partial condensate (B-1) of tetraalkoxysilanes and / or a partial condensation of trialkoxysilanes. Product (B-2), and a composition for transparent encapsulant containing an amine (C) having a boiling point of 5 ° C to 180 ° C,

（式（１）中、Ｒ^１はメチル、フェニル基又はトリフルオロプロピル基を表し、平均繰り返し単位数ａは３０〜１０００の整数を表す。）

(In formula (1), R ¹ represents a methyl, phenyl group or trifluoropropyl group, and the average repeating unit number a represents an integer of 30 to 1,000.)

In addition, the present invention relates to a cured product obtained by thermosetting the composition for transparent encapsulant, a transparent encapsulant made of the cured product, and a light-emitting diode encapsulated with the transparent encapsulant.

  The composition for transparent encapsulating material of the present invention is excellent in transparency, viscosity stability and handling properties, and has good curability. Further, the cured product of the present invention is excellent in hardness and crack resistance, and has initial transparency, light transmittance after heat treatment (hereinafter also referred to as heat resistance), and light transmittance after ultraviolet irradiation (hereinafter referred to as “heat resistance”). (It is also called light resistance.) Is also good, and in particular, the light extraction efficiency of short wavelength light of about 200 nm to 400 nm is excellent. Therefore, the cured product of the present invention is useful as a sealing material for various semiconductor light emitting devices, particularly as a transparent sealing material for ultraviolet light emitting diodes (UV-LEDs) and other high output light emitting devices. Moreover, this resin composition and hardened | cured material can also be utilized for sealing, protection, adhesion | attachment, etc. of not only a light emitting element but various light receiving elements, a photoelectric conversion element, and optical transmission related components.

  The resin composition for transparent encapsulant of the present invention (hereinafter also simply referred to as a resin composition) is a partial condensation of a predetermined polysiloxane (A) (hereinafter also referred to as (A) component) and tetraalkoxysilanes. Product (B-1) (hereinafter also referred to as component (B-1)) and / or partial condensate (B-1) of trialkoxysilane (hereinafter also referred to as component (B-2)) and predetermined The amine (C) (hereinafter also referred to as the component (C)) is an essential component.

  The component (A) is represented by the following general formula (1).

（式（１）中、Ｒ^１はメチル、フェニル基又はトリフルオロプロピル基を表し、平均繰り返し単位数ａは３０〜１０００の整数を表す。）

(In formula (1), R ¹ represents a methyl, phenyl group or trifluoropropyl group, and the average repeating unit number a represents an integer of 30 to 1,000.)

  Since the main chain structure of the component (A) does not include an organic covalent bond (C—C, C—O, etc.) and is composed only of a siloxane bond (Si—O—Si), It is thought to contribute to the initial transparency, heat resistance and light resistance of the cured product. In component (A), silanol groups (SiOH) are directly bonded to both ends of the main chain, and this silanol group reacts with an alkoxy group in component (B) described below in the presence of component (C). (Dealcoholization reaction) and the cured product of the present invention is formed.

  The component (A) has an average repeating unit number a of 30 or more and 1,000 or less, so it is well compatible with the component (B) described later, and the transparency, viscosity stability and handling properties of the resin composition of the present invention. In addition, it is considered that the initial transparency, heat resistance, light resistance, and the like of the cured product are improved. From this viewpoint, a is preferably 50 or more and 500 or less.

  As the component (A), various known compounds can be used without particular limitation as long as they are represented by the formula (1). In addition, the main chain of the component (A) may be a plurality of units having different structures. Specific examples of the component (A) include one selected from the group consisting of polydimethylsiloxane, polydimethyldiphenylsiloxane, polydiphenylsiloxane, polytrifluoropropylsiloxane, and the like. In addition, since the light resistance of the cured product of the present invention tends to be slightly impaired when the component (A) having a phenyl group is used, a polysiloxane having no phenyl group is specifically used as the component (A). Polydimethylsiloxane and / or polytrifluoropropylsiloxane are preferred.

  In addition to the component (A), other general commercially available polysiloxanes may be used in combination. Specifically, for example, polysiloxane containing a polyether or polycarbonate in the main chain structure, or an organic functional group such as aminopropyl group, glycidoxypropyl group, carbitol group, (meth) acryl group at the molecular end. And polysiloxane having a group. However, since these contain an organic covalent bond, even when combined with the component (B) described later, the resulting cured product has insufficient heat resistance.

  Examples of the tetraalkoxysilane that is the precursor of the component (B-1) include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, and tetrabutoxysilane. In addition, the component (B-1) is partially added to the tetraalkoxysilane by adding water that is usually about 0.125 to 0.5 equivalent when the total amount of the alkoxy group is 1 equivalent. It is obtained by hydrolysis and then condensation. Among the components (B-1), the tetramethoxysilane partial condensate and / or the tetraethoxysilane partial condensate rapidly cure with the component (A) in the presence of the component (C), This is preferable because it gives a resin composition having excellent viscosity stability and handling properties. Moreover, the cured product obtained from the resin composition is excellent in initial transparency, heat resistance, light resistance, and the like, and the light extraction efficiency is also improved.

  Examples of the tetraalkoxysilane that is the precursor of the component (B-2) include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n -Propyltrimethoxysilane, n-propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane and the like. In addition, the component (B-2) is partially added to the tetraalkoxysilane by adding water that is usually about 0.125 to 0.5 equivalent when the total amount of the alkoxy group is 1 equivalent. It is obtained by hydrolysis and then condensation. Among the components (B-2), the methyltrimethoxysilane partial condensate and / or the methyltriethoxysilane partial condensate undergo a rapid curing reaction with the aforementioned component (A) in the presence of the component (C), and are transparent. This is preferable because it gives a resin composition having excellent properties, viscosity stability and handling properties. Moreover, the cured product obtained from the resin composition is excellent in initial transparency, heat resistance, light resistance, and the like, and the light extraction efficiency is also improved.

The reaction product of the component (A) and the component (B-1) and / or the component (B-2) contains a free alkoxy group (preferably a methoxy group and / or an ethoxy group) derived from them. These undergo sol-gel reaction to form nanometer-sized fine silica particles. Therefore, it is considered that the cured product of the present invention is excellent in initial transparency, heat resistance, light resistance and the like.

  Component (C) is a curing catalyst used when the components (A) and (B) are reacted under heating.

  Component (C) is an amine having a boiling point of 5 ° C. to 180 ° C., and various known monoamines, diamines and alkanolamines can be used. Those having a boiling point of less than 5 ° C. are difficult to handle because they are gases at room temperature, and tend to evaporate from the resin composition of the present invention before acting as a curing catalyst. Moreover, it is because the thing exceeding 180 degreeC tends to remain in hardened | cured material, and exists in the tendency for any or all of initial transparency of this hardened | cured material, heat resistance, and light resistance to be impaired. From this viewpoint, the boiling point of the component (C) is preferably 30 to 170 ° C.

  As the component (C), a monoamine represented by the following general formula (2) is preferable.

（式（２）中、Ｘ^１、Ｘ^２及びＸ^３はそれぞれ水素又は炭素数が１〜６の飽和炭化水素を表す（ただし、Ｘ^１、Ｘ^２及びＸ^３が同時に水素である場合を除く。）。）

(In the formula (2), X ¹ , X ² and X ³ each represent hydrogen or a saturated hydrocarbon having 1 to 6 carbon atoms (except when X ¹ , X ² and X ³ are simultaneously hydrogen) .).)

  Specific examples of the component (C) represented by the general formula (2) include dimethylamine, ethylamine, diethylamine, triethylamine, n-propylamine, di-n-propylamine, tri-n-propylamine, isopropylamine, Diisopropylamine, diisopropylethylamine, cyclopropylamine, n-butylamine, di-n-butylamine, isobutylamine, methylethylamine, methylpropylamine, ethylpropylamine, methylisobutylamine, diisobutylamine, t-butylamine, di-t-butylamine , N-pentylamine, neopentylamine, methylpentylamine, n-hexylamine, cyclohexylamine, and the like. Among these, at least one selected from the group consisting of diethylamine, triethylamine, and diisopropylamine is such that the curing reaction of the component (A) and the component (B) proceeds rapidly, and initial transparency, heat resistance, light resistance, etc. Therefore, it is preferable to provide a cured product having a good balance.

  The composition of the present invention can be obtained by mixing the component (A), the component (B) and the component (C) by various known methods. Moreover, a mixing order is not specifically limited, They can be mixed at once, The composition containing (A) component and (C) component can be made into a main ingredient, and (B) component can also be mix | blended with this.

  The ratio of the component (A) and the component (B) in the resin composition of the present invention is not particularly limited. Usually, the amount of the component (B) used is 0.10 to 20 parts by weight relative to 100 parts by weight of the component (A). It is a range which becomes a grade. By using the component (B) within this range, the transparency, viscosity stability and handling properties of the resin composition of the present invention can be maintained, and the hardness and crack resistance of the cured product of the present invention, as well as initial transparency. , Heat resistance and light resistance are improved. From this viewpoint, the amount of component (B) used is preferably about 0.3 to 12 parts by weight per 100 parts by weight of component (A).

  The amount of the component (C) used in the resin composition of the present invention is not particularly limited, but usually the amount of the component (C) used is 0.05 to 100 parts by weight with respect to a total of 100 parts by weight of the components (A) and (B). The range is about 5.0 parts by weight. By using the component (C) within this range, the curing reaction of the component (A) and the component (B) proceeds smoothly, and the hardness and crack resistance of the cured product of the present invention and the initial stage Transparency, heat resistance and light resistance are improved. From this viewpoint, the amount of the component (C) used is about 0.1 to 3.5 parts by weight with respect to 100 parts by weight as the total of the components (A) and (B).

  Although the physical property of the resin composition of this invention is not specifically limited, For example, the viscosity measured with a Brookfield type | mold viscosity meter (rotor No. M3) is about 0.10-15Pa · s / 25 degreeC normally.

  In addition, various well-known additives can be mix | blended with the resin composition of this invention if it is a range which does not impair the expected effect effectively. Specifically, for example, inorganic phosphors, anti-aging agents, radical inhibitors, ultraviolet absorbers, adhesion improvers, flame retardants, surfactants, storage stability improvers, ozone degradation inhibitors, light stabilizers, potentiators Sticky agent, plasticizer, coupling agent, antioxidant, heat stabilizer, conductivity enhancer, antistatic agent, radiation blocking agent, nucleating agent, phosphorus peroxide decomposer, lubricant, pigment, metal deactivation Agents, physical property modifiers, organic solvents and inorganic fillers. By blending this inorganic filler, the refractive index of the cured product of the present invention and the fluidity of the resin composition can be adjusted to an appropriate range, or the hardness thereof can be improved. The type of the inorganic filler is not particularly limited, but is preferably in the form of fine particles that do not deteriorate the optical properties, for example, alumina, aluminum hydroxide, fused silica, crystalline silica, ultrafine amorphous silica, hydrophobic ultrafine silica, Examples include talc, calcium carbonate, and barium sulfate.

  The cured product of the present invention is obtained by thermally curing the resin composition of the present invention. Although heat curing may be performed in one stage, it is preferable to employ a step cure method that is performed in two stages as described below. That is, (a) the resin composition of the present invention is heated at a temperature lower than the boiling point of the component (C) (for example, about 20 to 50 ° C.), and the (A) component and the (B) component are subjected to a dealcoholization reaction. A primary cured product is used. Thereafter, (i) the primary cured product is heated at a temperature equal to or higher than the boiling point of the component (C) (for example, about 80 to 180 ° C.), and the component (B) is subjected to a sol-gel reaction in the primary cured product. The desired cured product can be obtained by volatilizing the component (C) from the primary cured product. In addition, the heating time of a process (a) is about 1 to 12 hours normally, and the heating time of a process (b) is about 1 to 5 hours normally.

The cured product thus obtained has a siloxane bond (Si—O—Si) derived from the component (A) as a main chain structure, and from the silanol group of the component (A) and the alkoxy group of the component (B) as a crosslinking site. The structure (Si—R ² —O to Si—R ³ —O) and the structure of silica (SiO ₂ ) derived from the alkoxy group of the component (B), and a carbon-carbon single bond or carbon-oxygen Since organic covalent bonds such as bonds are not included, it is considered that hardness and crack resistance, initial transparency, heat resistance, light resistance, and the like are good.

  Moreover, in the hardened | cured material of this invention, (C) component does not remain substantially, and even if it remains, the amount is less than 50 ppm, specifically about 0.1-50 ppm. The residual amount can be determined by various known means such as gas chromatography.

  The transparent sealing material of the present invention is composed of the cured product of the present invention, and does not contain an organic covalent bond such as a carbon-carbon single bond as described above. Even if it is exposed to short wavelength light, it does not easily deteriorate, and the light extraction efficiency of short wavelength light of about 200 nm to 400 nm is excellent. Therefore, it is useful as a transparent sealing material for semiconductor light-emitting elements, particularly light-emitting diodes (LEDs), especially (UV-LEDs) and other high-power light-emitting elements.

  The light emitting diode of the present invention is obtained by sealing and molding various light emitting elements with the transparent sealing material of the present invention. The light-emitting element is not particularly limited as long as it is a light-emitting element that can be used for a light-emitting diode. For example, a light-emitting element manufactured by stacking a semiconductor material such as a nitride-based compound semiconductor on a sapphire substrate can be given.

  The emission wavelength of the light-emitting element is not particularly limited, and may range from the ultraviolet region to the infrared region. However, the cured product of the present invention that seals the light-emitting diode of the present invention can extract light with a short wavelength of about 200 nm to 400 nm. Since the efficiency is excellent, the light emitting element preferably has a main emission peak wavelength of 400 nm or less. The light-emitting element may emit a single color using one kind, or may emit a single color or multicolor light in combination.

  A method for sealing the light-emitting element is not particularly limited, and known means can be applied. For example, the curable silicone resin composition for a transparent sealing material of the present invention may be injected into a cup, cavity, package recess, or the like having a light emitting element on the bottom by a dispenser or other means, and heated to be cured. The composition may be heated once to obtain a polymer having fluidity to some extent, and then injected, and further heated to be cured.

  The material of the base material on which the light emitting element is disposed is not particularly limited, and examples thereof include polycarbonate resin, polyphenylene sulfide resin, epoxy resin, acrylic resin, silicone resin, ABS resin, polybutylene terephthalate resin, and polyphthalamide resin.

  On the other hand, the light-emitting diode of the present invention is obtained by injecting the resin composition of the present invention into a mold frame in advance, immersing a lead frame or the like on which the light-emitting element is fixed, and then thermally curing the composition. Can also be obtained.

  In addition, the light-emitting diode of the present invention is sealed with the resin composition of the present invention by transfer molding, injection molding, or the like by injecting the resin composition of the present invention into a mold with the light-emitting element inserted therein. A method of forming a layer and curing it, a method of simply dropping the resin composition of the present invention on a light emitting device, or a method of curing by coating the resin composition, a resin composition of the present invention on a light emitting device Stencil printing, screen printing, a method of applying through a mask and curing it, and fixing a resin composition of the present invention partially or completely cured in a plate shape or a lens shape in advance on the light emitting element It can also be obtained by a method or the like.

  Further, the shape of the light emitting diode of the present invention is not particularly limited, and can be appropriately changed according to the application. Specifically, for example, a shell type shape adopted in a lighting fixture or the like, a surface mount type shape, and the like can be given.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated concretely, the scope of the present invention is not limited by these. In each example, parts and% are based on weight unless otherwise specified.

Example 1
100 parts by weight of polydimethylsiloxane having silanol groups at both ends (trade name: YF3057, manufactured by Momentive), 5.0 parts of tetramethoxysilane partial condensate (trade name: M silicate 51, manufactured by Tama Chemical Industries, Ltd.), And 2.1 parts of triethylamine (manufactured by Wako Pure Chemical Industries, Ltd.) were blended and stirred well, followed by vacuum defoaming to obtain a silicone composition. The composition is then poured into a Teflon (registered trademark) coated mold in an amount that results in a thickness of 1 mm after curing and heated at 25 ° C. for 5 hours and then at 150 ° C. for 1 hour, A cured product was obtained.

Examples 2-5
A cured product was obtained in the same manner as in Example 1 except that the raw materials used and the amounts used were changed to those shown in Table 1.

Comparative Examples 1 and 2 (corresponding to the resin composition of Patent Document 5 or 6)
In Example 1, the raw materials used and the amounts used were changed to those shown in Table 1, and cured products were obtained according to the curing conditions shown in Table 1. All of the obtained cured products had a sufficiently advanced curing reaction, were rubbery, and had an appropriate hardness.

Comparative Examples 3-5
In Example 1, the raw materials used and the amounts used were changed to those shown in Table 1, and cured products were obtained according to the curing conditions shown in Table 1. All of the obtained cured products had a sufficiently advanced curing reaction, were rubbery, and had an appropriate hardness.

Comparative Example 6
In Example 1, the raw materials used and the amounts used were changed to those shown in Table 1, and the prepared composition was cured in accordance with the conditions shown in Table 1, but the reaction did not proceed, and the composition was liquid. Remained.

(A) 1: Polydimethylsiloxane having silanol groups at both ends (the number of repeating units a = 430), trade name “YF3057”, manufactured by Momentive (A) 2: Polydimethylsiloxane having silanol groups at both ends (repeating units) Number a = 470), trade name “RHODOSILOILS48V3500”, manufactured by BLUESTAR SILICONES (A) 3: polydiphenyldimethylsiloxane having silanol groups at both ends (repeat unit number a = 350), trade name “PLY-7661”, NuSil Technology Product (A) 4: Polydimethylsiloxane having silanol groups at both ends (number of repeating units a = 80), trade name “YF3800”, manufactured by Momentive

(B-1): Tetramethoxysilane partial condensate, trade name “M silicate 51”, manufactured by Tama Chemical Industry Co., Ltd. (B-2): Methyltrimethoxysilane partial condensate, trade name “MTMS-A”, Made by Tama Chemical Industry Co., Ltd.

(C) 1: Triethylamine (boiling point 90 ° C), Wako Pure Chemical Industries, Ltd. (C) 2: Diethylamine (boiling point 55 ° C), Wako Pure Chemical Industries, Ltd. (C) 3: Diisopropylamine (boiling point 84 ° C) Manufactured by Wako Pure Chemical Industries, Ltd. (C) 4: cyclohexylamine (boiling point 134 ° C.), manufactured by Wako Pure Chemical Industries, Ltd.

Curing catalyst 1: Dibutyltin dilaurate, trade name “Neostan U-100”, manufactured by Nitto Kasei Co., Ltd.
Curing catalyst 2: diisopropoxyaluminum ethyl acetoacetate, trade name “ALCH”, cure catalyst manufactured by Kawaken Fine Chemical Co., Ltd .: 2-ethyl-4-methylimidazole (boiling point 292-295 ° C.), trade name “CUREZOLE 2E4MZ ”, Shikoku Kasei Co., Ltd. curing catalyst 4: 1,8-diazabicyclo [5.4.0] -7-undecene (boiling point 261 ° C.), trade name DBU, Sun Apro Co., Ltd. curing catalyst 5: tributylamine ( Boiling point: 216 ° C), Wako Pure Chemical Industries, Ltd., curing catalyst 6: acetic acid, manufactured by Kishida Chemical Co., Ltd.

Comparative Example 7 (corresponding to the resin composition of Patent Document 3 or 4)
Addition-curable polydimethylsiloxane composition containing a platinum compound as a catalyst (a mixture of a silicone polymer having a vinyl group and a silicone polymer having a SiH group. Product name “KER-2500”, manufactured by Shin-Etsu Chemical Co., Ltd.) The cured product was obtained by injecting into a mold having a Teflon (registered trademark) coat in an amount such that the thickness after curing was 1 mm, and heating at 100 ° C. for 1 hour and then at 150 ° C. for 5 hours.

Comparative Example 8 (corresponding to the resin composition of Patent Document 3 or 4)
Curing an addition-curable polyphenylmethylsiloxane composition containing a platinum compound as a catalyst (a mixture of a silicone polymer having a vinyl group and a silicone polymer having a SiH group. The trade name “OE-6636”, manufactured by Dow Corning) The cured product was obtained by pouring into a mold with a Teflon (registered trademark) coating in an amount such that the subsequent thickness was 1 mm and heating at 150 ° C. for 1 hour.

<Evaluation of cured product>
(Curable)
Each hardened | cured material of Examples 1-5 and Comparative Examples 1-5 and 7-8 is a rubber-like thing in which hardening fully progressed, and all determined that curability was (circle). The results are shown in Table 2.

(Initial transmittance)
About each of hardened | cured material of Examples 1-5 and Comparative Examples 1-5 and 7-8, the absorption spectrum of ultraviolet visible light was measured with the ultraviolet visible spectrophotometer V-560 (made by JASCO Corporation). The transmittance at 300 nm was read. And the thing whose value is less than 80% was made into x, and the thing whose value was 80% or more was made into (circle). The results are shown in Table 2.

(Light resistance test (transmittance))
Each of the cured products of Examples 1 to 5 and Comparative Examples 1 to 5 and 7 to 8 was subjected to a super accelerated weathering tester (product name “I Super UV Tester SUV-F11”, manufactured by Iwasaki Electric Co., Ltd.)) It was left still and irradiated with light having a wavelength of 295 to 450 nm at an intensity of 100 mW / cm ² for 168 h. At this time, the temperature of each hardened | cured material was 55-60 degreeC. Thereafter, the ultraviolet transmittance at 300 nm was read for each cured product according to the same method as described above. And the value was set to x when the value was less than 80%, and ◯ when the value was 80% or more. The results are shown in Table 2.

(Heat resistance test (transmittance))
Each of the cured products of Examples 1 to 5 and Comparative Examples 1 to 5 and 7 to 8 was allowed to stand in a 200 ° C. normal air dryer and left for 168 hours. Thereafter, the ultraviolet transmittance at 300 nm was read for each cured product according to the same method as described above. And the thing whose value is less than 80% was made into x, and the thing more than 80% was made into (circle). The results are shown in Table 2.

(Heat resistance test (weight reduction))
Each of the cured products of Examples 1 to 5 and Comparative Examples 1 to 5 and 7 to 8 was allowed to stand in a 200 ° C. normal air dryer and left for 168 hours. Thereafter, each cured product was weighed, and compared with the weight before heating, the weight reduction rate (%) was calculated. And the thing whose value is less than 70% was made into x, the thing 70% or more and less than 80% was set to (triangle | delta), and the thing 80% or more was made into (circle). The results are shown in Table 2.

Claims (9)

A polysiloxane (A) having silanol groups at both ends represented by the following general formula (1), a partial condensate (B-1) of tetraalkoxysilanes and / or a partial condensate of trialkoxysilanes (B-2) ), And an amine (C) having a boiling point of 5 ° C. to 180 ° C. and containing no metal catalyst .

(In formula (1), R ¹ represents a methyl, phenyl group or trifluoropropyl group, and the average repeating unit number a represents an integer of 30 to 1,000.) (B-1) The composition for transparent sealing materials of Claim 1 whose component is a tetramethoxysilane partial condensate and / or a tetraethoxysilane partial condensate. (B-2) The composition for transparent sealing materials of Claim 1 or 2 whose component is a methyltrimethoxysilane partial condensate and / or a methyltriethoxysilane partial condensate. (C) The composition for transparent sealing materials in any one of Claims 1-3 whose component is an amine represented by following General formula (2).

(In the formula (2), X ¹ , X ² and X ³ each represent hydrogen or a saturated hydrocarbon having 1 to 6 carbon atoms (except when X ¹ , X ² and X ³ are simultaneously hydrogen) .).) The composition for transparent sealing materials in any one of Claims 1-4 whose usage-amount of (B) component with respect to 100 weight part of (A) component is 0.10-20 weight part. The composition for transparent sealing materials according to any one of claims 1 to 5, wherein the amount of the component (C) used is 0.05 to 5.0 parts by weight relative to 100 parts by weight of the total of the components (A) and (B). object. Hardened | cured material obtained by thermosetting the composition for transparent sealing materials in any one of Claims 1-6. A transparent sealing material comprising the cured product according to claim 7. A light-emitting diode encapsulated with the transparent encapsulant of claim 8.