JP5377401B2 - Curable organopolysiloxane composition - Google Patents

Abstract

The invention provides a solidified organic polysiloxanes composition, comprising organic polysiloxanes (A-I), organic polysiloxanes (A-II), wherein the rate of (A-I) and (A-II) in weight is 1/99-99/1, straight chain organic hydrogen polysiloxanes (B) which has a content equal to the total number of alkenyls bonded with silicon atoms in (A-I) and (A-II), and has 0.3-10 hydrogen atoms bonded with silicon atoms, and an addition reaction catalyst (C) which is a catalyst amount. The solidified organic polysiloxanes composition has high transparency, and high tolerance to thermal shock, due to which crack is hard to generate even under harsh temperature circulation.

Description

  The present invention relates to a curable organopolysiloxane composition and a semiconductor device. More specifically, the present invention relates to a curable organopolysiloxane composition that forms a cured product having good crack resistance even under high temperature / low temperature cycle conditions, and the cured product. The present invention relates to a semiconductor device that is covered with a semiconductor element and has excellent reliability.

  Since semiconductor devices are used in various fields, semiconductor elements and the like constituting the semiconductor devices are placed in various environments and are sometimes greatly affected by them. In particular, it is known that when the LED is energized / lighted, a rapid temperature rise occurs and the LED element is subjected to thermal shock. Therefore, the LED element is subjected to a severe temperature cycle by repeatedly turning on and off the LED element.

  Epoxy resin is generally used as a sealing material for semiconductor elements such as LED elements. However, since the elastic modulus of the epoxy resin is high, the bonding wire may be disconnected due to stress due to a temperature cycle or the like, or the epoxy resin may be cracked. In particular, when used as a sealing material for a light emitting element, there is a concern that the light emitting efficiency may be lowered due to the collapse of the crystal structure of the semiconductor material due to the stress applied to the LED chip by the epoxy resin.

  As a countermeasure, a method of using room temperature curable silicone rubber as a buffer material and sealing the outside with an epoxy resin has been established as a standard method. However, in this method, since the epoxy resin does not adhere to the silicone resin, peeling occurs at the interface between the epoxy resin and the silicone rubber due to stress such as a temperature cycle, and the light extraction efficiency decreases extremely with time. It has been known.

Therefore, it has been proposed to use a silicone resin as a material replacing the epoxy resin (Patent Documents 1, 2, and 3). Silicone resins are superior in heat resistance, weather resistance, and discoloration resistance compared to epoxy resins, and in recent years, examples of being used mainly for blue LEDs and white LEDs are increasing.
However, although these silicone resins have a lower elastic modulus than epoxy resins, they also have a problem that cracks are likely to occur due to thermal shocks that occur during energization / lighting of the LED due to low mechanical properties such as bending strength.

Japanese Patent Laid-Open No. 11-1619 JP 2002-265787 A JP 2004-186168 A

  The present invention has been made in view of the above circumstances, and provides a curable organopolysiloxane composition having high transparency, particularly high resistance to thermal shock, and being less susceptible to cracking even under severe temperature cycles. For the purpose.

In order to solve the above problems, the present invention provides at least
(AI): having at least two silicon-bonded alkenyl groups in one molecule, the following general formula (1)
RSiO _3/2 (1)
(Wherein R is a substituted or unsubstituted monovalent hydrocarbon group)
An organopolysiloxane having a branched structure containing 5 to 70 mol% of a siloxane unit represented by:
(A-II): Organo having a branched structure having at least two silicon atom-bonded alkenyl groups in one molecule and containing at least 70 mol% of the siloxane unit represented by the general formula (1) Polysiloxane in an amount of (AI) / (A-II) = 1/99 to 99/1 by weight unit,
(B): The following average composition formula (2)
R ¹ _a H _b SiO _{(4-ab) / 2} (2)
(Wherein R ¹ is a substituted or unsubstituted monovalent hydrocarbon group excluding an aliphatic unsaturated hydrocarbon group, a and b are 0.7 ≦ a ≦ 2.1 and 0.01 ≦ b ≦ 1.0. And a positive number satisfying 0.8 ≦ a + b ≦ 2.9)
A linear organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in one molecule and having a viscosity at 25 ° C. of 1000 mPas or less, the number of hydrogen atoms bonded to the silicon atom Is an amount such that 0.3 to 10 per one total number of silicon-bonded alkenyl groups in the components (AI) and (A-II),
(C): Addition reaction catalyst A curable organopolysiloxane composition containing a catalytic amount is provided.

  Such a curable organopolysiloxane composition of the present invention has high transparency because of its excellent resistance to discoloration, and has a particularly severe temperature cycle because of its high resistance to thermal shock. Cracks and delamination are unlikely to occur even underneath.

In this case, it is preferable that the (AI) component is liquid at 25 ° C. and the (A-II) component is solid at 25 ° C.
Thus, at 25 ° C., if the (AI) component is liquid and the (A-II) component is solid, it is easier to impart thermal shock resistance and strength.

In this case, the components (AI), (A-II), and (B) preferably have at least one silicon atom-bonded aryl group in one molecule.
As described above, (AI) to (B) each component having at least one silicon-bonded aryl group in one molecule can obtain the necessary hardness and strength as a silicone resin and is cured. The heat resistance, low-temperature characteristics, and transparency of the coating protective material are particularly good, and reliability by a thermal shock test is also obtained.

The present invention also provides a semiconductor device wherein a semiconductor element is covered with a cured product of the curable organopolysiloxane composition.
Thus, if the semiconductor element is coated with the curable organopolysiloxane composition of the present invention having particularly high thermal shock resistance and excellent transparency, the resulting semiconductor device can be applied to various fields and useful. It will be something.

In this case, the semiconductor element is preferably a light emitting element.
The curable organopolysiloxane composition of the present invention has a particularly high resistance to thermal shock and is less prone to cracking. Therefore, as described above, a light emitting device that is subjected to a severe temperature cycle As a sealing material for covering the film, it can be particularly preferably used.

  As described above, the curable organopolysiloxane composition of the present invention has particularly high thermal shock resistance and excellent transparency. Therefore, it is also useful as a potting material in various fields such as electric / electronic, OA equipment, automobiles and precision equipment, as a material for light emitting diode elements and other optical devices or optical components.

It is sectional drawing which shows typically an example of the light-emitting semiconductor device with which the curable organopolysiloxane composition of this invention is used suitably.

Hereinafter, the present invention will be described in more detail.
As described above, the conventionally used sealing materials for semiconductor elements have a problem that cracks are likely to occur due to thermal shock that occurs particularly during energization / lighting of the LED, and severe temperature cycling is required. There has been a demand for a sealing material that does not easily crack or peel off.

  Accordingly, the present inventors have conducted intensive research and found that the above-mentioned problems can be achieved by combining organopolysiloxanes having two types of branched structures having different branch unit contents, and a curable organopolysiloxane composition. It came to complete.

That is, the curable organopolysiloxane composition of the present invention has at least
(AI): having at least two silicon-bonded alkenyl groups in one molecule, the following general formula (1)
RSiO _3/2 (1)
(Wherein R is a substituted or unsubstituted monovalent hydrocarbon group)
An organopolysiloxane having a branched structure containing 5 to 70 mol% of a siloxane unit represented by:
(A-II): Organo having a branched structure having at least two silicon atom-bonded alkenyl groups in one molecule and containing at least 70 mol% of the siloxane unit represented by the general formula (1) Polysiloxane in an amount of (AI) / (A-II) = 1/99 to 99/1 by weight unit,
(B): The following average composition formula (2)
R ¹ _a H _b SiO _{(4-ab) / 2} (2)
(Wherein R ¹ is a substituted or unsubstituted monovalent hydrocarbon group excluding an aliphatic unsaturated hydrocarbon group, a and b are 0.7 ≦ a ≦ 2.1 and 0.01 ≦ b ≦ 1.0. And a positive number satisfying 0.8 ≦ a + b ≦ 2.9)
A linear organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in one molecule and having a viscosity at 25 ° C. of 1000 mPas or less, the number of hydrogen atoms bonded to the silicon atom Is an amount such that 0.3 to 10 per one total number of silicon-bonded alkenyl groups in the components (AI) and (A-II),
(C): Addition reaction catalyst A catalyst amount is contained.

Hereinafter, each component of the present invention will be described in detail.
Hereinafter, the (AI) component and the (A-II) component may be simply referred to as the (A) component.
<(AI) component>
The component (AI) has an alkenyl group bonded to at least two silicon atoms in one molecule, and has the following general formula (1)
RSiO _3/2 (1)
An organopolysiloxane having 5 to 70 mol% of siloxane units represented by the formula, preferably having a liquid branched structure at 25 ° C. The component (A-I) is a component that gives the composition of the present invention high resistance to thermal shock and is resistant to cracking even under severe temperature cycles. Therefore, the content of this RSiO _3/2 unit is 5 to 70 mol%, more preferably 20 to 60 mol%. If the amount is less than 5 mol%, sufficient thermal shock resistance of the cured product cannot be obtained, and if it exceeds 70 mol%, it becomes difficult to maintain a good liquid state at 25 ° C.
Other siloxane units include R ₂ SiO _2/2 units, R ₃ SiO _1/2 units, and SiO _4/2 units (wherein R is the same or different substituted or unsubstituted monovalent hydrocarbons). Group). In this case, a part of R may be substituted with a hydroxyl group and / or an alkoxy group.
Of these, R ₂ SiO _2/2 units and / or R ₃ SiO _1/2 units are preferred.

  In the above general formula (1), the substituted or unsubstituted monovalent hydrocarbon group bonded to the silicon atom represented by R is usually an unsubstituted or substituted group having 1 to 20 carbon atoms, particularly preferably 1 to 10 carbon atoms. Specific examples of such hydrocarbon groups include monovalent hydrocarbon groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, cyclohexyl, and heptyl groups; phenyl Group, tolyl group, xylyl group, naphthyl group and other aryl groups; benzyl group, phenethyl group and other aralkyl groups; vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, heptenyl group and other alkenyl groups Hydrocarbon groups; halogenated alkyl groups such as chloromethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group, and the like.

(A-I) Component 1 molecule must contain at least two silicon-bonded alkenyl groups. Further, 0.1 to 20 mol%, preferably 0 It is preferable that 5-10 mol% is an alkenyl group. When the content of the alkenyl group is 0.1 to 20 mol%, suitable hardness as a silicone resin can be obtained and crack resistance is further improved.
Further, it is preferable to contain silicon-bonded aryl groups in all silicon-bonded organic groups of (A-I) component, more preferably 5 to 100 mol%, particularly preferably 10 to 100 mol%. As the aryl group, a phenyl group is particularly preferable.

<(A-II) component>
The component (A-II) has at least two silicon-bonded alkenyl groups in one molecule and exceeds at least 70 mol% of the siloxane unit represented by the general formula (1) (RSiO _3/2 ). Preferably, it is an organopolysiloxane having a solid branched structure at 25 ° C. The component (A-II) imparts strength to the composition of the present invention. For this purpose, the RSiO _3/2 unit must have a content of at least 70 mol%, preferably 75 mol% or more.
Other siloxane units include R ₂ SiO _2/2 units, R ₃ SiO _1/2 units, and SiO _4/2 units as in the case of the component (AI). In the formula, R is the same as described above.

In the component (A-II), it is necessary that at least two silicon atom-bonded alkenyl groups are contained in one molecule of the component (A-II). It is preferable that mol%, preferably 5 to 20 mol% is an alkenyl group. When the content of the alkenyl group is from 1 mol to 30 mol%, particularly suitable hardness as a silicone resin is obtained, and crack resistance is further improved.
Moreover, it is preferable to contain a silicon atom bond aryl group in the silicon atom bond all organic group of (A-II) component, More preferably, it is 5-100 mol%, Most preferably, it is 10-100 mol%. As the aryl group, a phenyl group is particularly preferable.
Of these, R ₂ SiO _2/2 units and / or R ₃ SiO _1/2 units are preferred.

  The amount of component (A-II) is such that the ratio of the content of this component to component (AI) is 1/99 to 99/1 by weight, preferably 10/90 to 90/10. And is particularly preferably 20/80 to 80/20. This is because the strength of the resulting cured product tends to decrease when the content of the component (A-II) is less than the lower limit of the above range. On the other hand, when the upper limit of the above range is exceeded, the handling workability of the resulting composition tends to decrease, or the resulting cured product tends to be extremely hard.

  In the present invention, the siloxane unit represented by the general formula (1) is the same as that contained in the component (AI) and that contained in the component (A-II). It may be different.

<(B) component>
The organohydrogenpolysiloxane of component (B) has the following average composition formula (2)
R ¹ _a H _b SiO _{(4-ab) / 2} (2)
(Wherein R ¹ is a substituted or unsubstituted monovalent hydrocarbon group excluding an aliphatic unsaturated hydrocarbon group, a and b are 0.7 ≦ a ≦ 2.1 and 0.01 ≦ b ≦ 1.0. And a positive number satisfying 0.8 ≦ a + b ≦ 2.9)
A linear organohydro having at least two silicon-bonded hydrogen atoms in one molecule and having a viscosity at 25 ° C. of 1000 mPas or less, usually 0.5 to 1000 mPas, preferably 1 to 500 mPas. Genpolysiloxane.

Here, R ¹ is preferably a substituted or unsubstituted monovalent hydrocarbon group excluding an aliphatic unsaturated hydrocarbon group having 1 to 12 carbon atoms, particularly preferably about 1 to 10 carbon atoms. Specific examples of the hydrocarbon group include methyl groups, ethyl groups, propyl groups, butyl groups, pentyl groups, hexyl groups, cyclohexyl groups, heptyl groups and other alkyl groups; phenyl groups, tolyl groups, xylyl groups, naphthyl groups, and the like. Aryl groups; aralkyl groups such as benzyl group and phenethyl group; halogenated alkyl groups such as chloromethyl group, 3-chloropropyl group and 3,3,3-trifluoropropyl group. A and b are 0.7 ≦ a ≦ 2.1, preferably 1.0 ≦ a ≦ 2.0, 0.01 ≦ b ≦ 1.0, preferably 0.02 ≦ b ≦ 1.0, More preferably 0.10 ≦ b ≦ 1.0 and 0.8 ≦ a + b ≦ 2.9, preferably 1.01 ≦ a + b ≦ 2.8, more preferably 1.6 ≦ a + b ≦ 2.7. If b is less than 0.01, sufficient hardness as a silicone resin cannot be obtained.

The molecular structure of the organohydrogenpolysiloxane is not particularly limited, but is preferably linear, and bonded to a silicon atom from the viewpoint of compatibility with the component (A) and physical properties of the cured product. Among R ¹ and H (hydrogen atom), those in which 5 mol% or more, preferably 10 to 50 mol% are phenyl groups, are suitably used. In the case where R ¹ is other than a phenyl group, a methyl group is preferable.
The blending amount of the organohydrogenpolysiloxane of component (B) is such that the number of hydrogen atoms bonded to silicon atoms is 0.3 to 1 per total number of alkenyl groups bonded to silicon atoms in component (A). It is preferable that 10 is mixed. If it is less than 0.3, the curing becomes sweet, and if it exceeds 10, the cured product becomes too brittle. Preferably it is 0.5-5.

<(C) component>
The addition reaction catalyst for component (C) is a catalyst for crosslinking by addition reaction between component (A) and component (B). Examples thereof include chloroplatinic acid, chloroplatinic acid and monohydric alcohol. Examples include reactants, olefin complexes of chloroplatinic acid, coordination compounds of chloroplatinic acid and vinylsiloxane, platinum-based catalysts such as platinum black, palladium-based catalysts, rhodium-based catalysts, etc. Usually a platinum catalyst is used. In particular, a low chlorine catalyst that does not corrode metals is preferable when used in the production of a sealed LED in the electronics field in this application, and among them, divinyltetramethyldisiloxane and divinyldiphenyldimethyldisilane containing no chlorine component are preferable. Those modified with siloxane or the like are preferable.
These addition reaction catalysts may be used alone or in combination of two or more.

  The addition amount of the addition reaction catalyst is an effective amount (catalyst amount) that acts as a catalyst, and is preferably 1 to 1000 ppm with respect to the total amount of the components (A) and (B). If it is 1 ppm or more, curing proceeds at an appropriate speed, and if it is 1000 ppm or less, the workable time does not become too short, and the cured product is not easily yellowed, which is economical. Most preferably, it is 5-100 ppm.

<Optional component>
In the composition of the present invention, as the optional components other than the above components (A) to (C), for example, all conventionally known control agent compounds which are compounds having a curing inhibitory effect on the addition reaction catalyst are used. Can be used. Such compounds include phosphorus-containing compounds such as triphenylphosphine, nitrogen-containing compounds such as tributylamine, tetramethylethylenediamine, and benzotriazole, sulfur-containing compounds, acetylenic compounds, compounds containing two or more alkenyl groups, hydropar Examples include oxy compounds and maleic acid derivatives. Since the degree of cure retarding effect by the control agent compound varies greatly depending on the chemical structure of the control agent compound, it is preferable to adjust the addition amount of the control agent compound to an optimum amount for each of the control agent compounds used. Is an amount in such a range that long-term storage stability at room temperature can be obtained and curing is not hindered, and is usually 0.1 parts per 100 parts by mass in total of the components (A- I ) and (A- II ). It is used in an amount of 5 parts by mass or less, preferably 0.01 to 0.3 parts by mass.

  Moreover, you may contain the adhesion imparting agent for improving the adhesiveness in the composition of this invention. The adhesion-imparting agent is preferably an organosilicon compound having at least one alkoxy group bonded to a silicon atom in one molecule. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, and a methoxyethoxy group, and a methoxy group is particularly preferable. In addition, the group other than the alkoxy group bonded to the silicon atom of the organosilicon compound is the same as that exemplified as the R group, usually 1 to 12 carbon atoms, preferably about 1 to 10 carbon atoms, unsubstituted or In addition to halogen-substituted monovalent hydrocarbon groups, epoxy functional group-substituted alkyl groups such as γ-glycidoxypropyl group, β- (3,4-epoxycyclohexyl) ethyl group, hydrogen atoms, etc. Preferable examples include a methyl group, an ethyl group, a propyl group, a phenyl group, a vinyl group, a hydrogen atom, and a γ-glycidoxypropyl group.

The present invention also provides a semiconductor device coated and protected with the above-described curable organopolysiloxane composition of the present invention.
An example of the semiconductor device of the present invention is shown in FIG. 1, but is not limited to this. Here, in FIG. 1, 1 is a housing | casing, 2 is a light emitting element, 3, 4 is a lead electrode, 5 is a die-bond material, 6 is a gold wire, 7 is sealing resin (composition of this invention).
Such a semiconductor device 8 of the present invention is excellent in heat resistance, moisture resistance and light resistance of the device, and the device does not corrode. As a result, it is possible to provide a semiconductor device having excellent reliability, and industrially. The benefits are great.

EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example etc.
[Example 1]
Average unit formula: (PhSiO _3/2 ) _0.5 [(CH ₂ ═CH) Me ₂ SiO _0.5 ] _0.25 (Me ₃ SiO _0.5 ) _0.25 Organopolysiloxane [Viscosity at 25 ° C. of 3500 mPas, silicon atom-bonded vinyl group content = 12.5 mol%, silicon atom-bonded phenyl group content in all silicon atom-bonded organic groups = 25 mol%, standard styrene Converted weight average molecular weight = 1200] 50 parts by mass, (PhSiO _3/2 ) _0.8 [(CH ₂ ═CH) Me ₂ SiO _0.5 ] _0.2 Organo having a solid branched structure Polysiloxane [content of silicon atom-bonded vinyl group = 14.3 mol%, content of silicon atom-bonded phenyl group in all silicon atom-bonded organic groups = 57 mol%, standard styrene conversion The weight average molecular weight of = 2350] 50 parts by _{weight, HMe 2 SiO (Ph 2 SiO} ) has the structure of 1 SiMe ₂ H, organohydrogenpolysiloxane 30 parts by weight a viscosity of 4MPas, chloroplatinic acid / 1,3 -Uniformity of 0.06 parts by mass of a toluene solution containing 1% by mass of a divinyltetramethyldisiloxane complex as a platinum atom content, 0.05 parts by mass of ethynylcyclohexanol, and 3 parts by mass of γ-glycidoxypropyltrimethoxysilane By mixing, a silicone composition (U) was prepared. When this silicone composition (U) was cured by heating at 150 ° C. for 4 hours, the hardness was 60 in Shore D.

[Example 2]
Average unit formula: (PhSiO _3/2 ) _0.5 [(CH ₂ ═CH) Me ₂ SiO _0.5 ] _0.25 (Me ₃ SiO _0.5 ) _0.25 Organopolysiloxane [Viscosity at 25 ° C. of 3500 mPas, content of silicon atom-bonded vinyl group = 12.5 mol%, content of silicon atom-bonded phenyl group in silicon atom-bonded organic group = 25 mol%, standard styrene conversion Weight average molecular weight = 1200] 80 parts by mass, (PhSiO _3/2 ) _0.75 [(CH ₂ = CH) Me ₂ SiO _0.5 ] _0.25 Organopoly having a solid branched structure Siloxane [Content of silicon atom-bonded vinyl group = 17 mol%, Content of silicon atom-bonded phenyl group in all silicon atom-bonded organic groups = 50 mol%, standard styrene conversion Weight average molecular weight = 1600] 20 parts by mass, organoatom having a viscosity of 20 mPas with a hydrogen gas generation rate of 140 ml / g having 30 mol% of phenyl groups based on the total of hydrogen atoms, phenyl groups and methyl groups bonded to silicon atoms 32 parts by mass of hydrogen polysiloxane, 0.5 parts by mass of a toluene solution containing 1% by mass of chloroplatinic acid / 1,3-divinyltetramethyldisiloxane complex as a platinum atom content, 0.05 parts by mass of ethynylcyclohexanol, And 3 parts by mass of γ-glycidoxypropyltrimethoxysilane were uniformly mixed to prepare a silicone composition (V). When the silicone composition (V) was cured by heating at 150 ° C. for 4 hours, the hardness was 65 in Shore D.

[Example 3]
Average unit formula: (PhSiO _3/2 ) _0.17 [(CH ₂ ═CH) Me ₂ SiO _0.5 ] _0.5 (Ph ₂ SiO) Organopoly having a liquid branched structure represented by _0.33 Siloxane [Viscosity at 25 ° C. of 440 mPas, silicon atom-bonded vinyl group content = 21.5 mol%, silicon atom-bonded phenyl group content in silicon atom-bonded organic group = 35.6 mol%, in terms of standard styrene Weight average molecular weight = 1000] 17 parts by mass, (PhSiO _3/2 ) _0.75 [(CH ₂ ═CH) Me ₂ SiO _0.5 ] _0.25 Organopolysiloxane having a solid branched structure [Content of silicon atom-bonded vinyl group = 17 mol%, content of silicon atom-bonded phenyl group in organic group before silicon atom bonding = 50 mol%, weight in terms of standard styrene Average molecular weight = 1600] 83 parts by mass, 34.5 parts by mass of an organohydrogenpolysiloxane having a structure of HMe ₂ SiO (Ph ₂ SiO) ₁ SiMe ₂ H and a viscosity of 4 mPas at 25 ° C., chloroplatinic acid / 0.5 parts by mass of a toluene solution containing 1% by mass of a 1,3-divinyltetramethyldisiloxane complex as a platinum atom content, 0.05 parts by mass of ethynylcyclohexanol, and 3 parts by mass of γ-glycidoxypropyltrimethoxysilane Parts were uniformly mixed to prepare a silicone composition (W). When the silicone composition (W) was cured by heating at 150 ° C. for 4 hours, the hardness was 46 in Shore D.

[Comparative Example 1]
Average unit formula: (PhSiO _3/2 ) _0.5 [(CH ₂ ═CH) Me ₂ SiO _0.5 ] _0.25 (Me ₃ SiO _0.5 ) _0.25 Organopolysiloxane [viscosity 3500 mPas, silicon atom-bonded vinyl group content = 12.5 mol%, silicon atom-bonded phenyl group content in all silicon atom-bonded organic groups = 25 mol%, weight in terms of standard styrene In place of the average molecular weight = 1200], 50 parts by mass of a methylphenylvinylsiloxy group-blocked diphenylsiloxane copolymer having a main chain composed only of diphenylsiloxane units and a viscosity of 0.4 Pas, HMe ₂ SiO (Ph ₂ SiO) ₁ Although except for using organohydrogenpolysiloxane 29 parts by weight having the structure SiMe 2 _H was in example 1 Composition (X) was prepared Te. When the silicone composition (X) was cured by heating at 150 ° C. for 4 hours, the hardness was 56 for Shore D.

[Comparative Example 2]
Average unit formula: (PhSiO _3/2 ) _0.5 [(CH ₂ ═CH) Me ₂ SiO _0.5 ] _0.25 (Me ₃ SiO _0.5 ) _0.25 Organopolysiloxane [viscosity 3500 mPas, silicon atom-bonded vinyl group content = 12.5 mol%, silicon atom-bonded phenyl group content in all silicon atom-bonded organic groups = 25 mol%, weight in terms of standard styrene Instead of the average molecular weight = 1200], the main chain is composed only of diphenylsiloxane units, and the viscosity is 0.4 Pas. Both ends of the methylphenylvinylsiloxy group-blocked diphenylsiloxane copolymer are 80 parts by mass, hydrogen atoms bonded to silicon atoms, phenyl The hydrogen gas generation amount having a phenyl group of 30 mol% with respect to the total of the group and methyl group is 140 ml / g, the viscosity is 20 m Except for using the organohydrogenpolysiloxane 31 parts by weight of as the composition of (Y) was prepared according to Example 2. When the silicone composition (Y) was cured by heating at 150 ° C. for 4 hours, the hardness was 60 in Shore D.

[Comparative Example 3]
Average unit formula: (PhSiO _3/2 ) _0.17 [(CH ₂ ═CH) Me ₂ SiO _0.5 ] _0.5 (Ph ₂ SiO) Organopoly having a liquid branched structure represented by _0.33 Siloxane [viscosity: 440 mPas, silicon atom-bonded vinyl group content = 21.5 mol%, silicon atom-bonded phenyl group content in silicon atom-bonded organic group = 35.6 mol%, weight average molecular weight in terms of standard styrene = 1000], 26 parts by mass of a methylphenylvinylsiloxy group-blocked diphenylsiloxane copolymer having a main chain consisting only of diphenylsiloxane units and a viscosity of 0.4 Pas, (PhSiO _3/2 ) _0.75 [( CH ₂ = CH) Me ₂ SiO _0.5 ] Organopolysiloxane having a solid branched structure represented by _0.25 [silicon atom Bonded vinyl group content = 17 mol%, silicon atom bonded phenyl group content in organic group before silicon atom bonding = 50 mol%, weight average molecular weight in terms of standard styrene = 1600] 74 parts by mass, HMe ₂ SiO ( A composition (Z) was prepared according to Example 3 except that 31.6 parts by mass of an organohydrogenpolysiloxane having a structure of (Ph ₂ SiO) ₁ SiMe ₂ H and having a viscosity at 25 ° C. of 4 mPas was used. When this silicone composition (Z) was cured by heating at 150 ° C. for 4 hours, the hardness was 40 in Shore D.

The evaluation methods in the silicone compositions (U) to (Z) prepared in the above Examples and Comparative Examples were performed as follows.
[Evaluation method]
As the light emitting semiconductor package light emitting element, a light emitting semiconductor device 8 as shown in FIG. 1 having a light emitting layer made of InGaN and mounting an LED chip having a main light emission peak of 470 nm was used. The curing conditions for the sealing resin 7 are 150 ° C. and 4 hours.

Humidity resistance and infrared reflow test method 10 light emitting semiconductor devices each were placed in a constant temperature and humidity chamber at 85 ° C and 85% for 24 hours, and then passed through an infrared reflow device (260 ° C) three times to change the appearance. Observed. The results are shown in Table 1. In addition, the thing by which the crack of resin and the peeling from an LED package were confirmed was counted as NG.

As shown in Table 1, in Examples 1 to 3, the NG number is 0, the crack resistance is good even under high temperature / low temperature cycle conditions, no peeling occurs, and the light extraction efficiency is high. I understand. Moreover, such a silicone resin was also excellent in transparency.
On the other hand, in Comparative Examples 1 to 3, cracks of the resin and peeling from the LED package occurred in more than half. Thereby, when a conventional thing is used as a sealing material, it turns out that productivity of LED will worsen.

  From the above, the curable organopolysiloxane composition of the present invention has a particularly high resistance to thermal shock, so that it is difficult to generate cracks and has high transparency. In addition, it has been proved useful as a material for optical components and a potting material in various fields, particularly as a sealing material for light-emitting elements that are subjected to severe temperature cycles.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

DESCRIPTION OF SYMBOLS 1 ... Housing | casing 2 ... Light emitting element 3, 4 ... Lead electrode 5 ... Die-bonding material,
6 ... gold wire, 7 ... sealing resin, 8 ... semiconductor device (light emitting semiconductor device).

Claims (4)

(AI): having at least two silicon-bonded alkenyl groups in one molecule, the following general formula (1)
RSiO _3/2 (1)
(Wherein R is a substituted or unsubstituted monovalent hydrocarbon group)
In the siloxane units represented have a branched structure containing 5-70 mole%, the organopolysiloxane that is liquid at 25 ° C.,
(A-II): has at least two silicon-bonded alkenyl groups per molecule, have a branched structure containing more than at least 70 mol% of siloxane units represented by the above general formula (1) An organopolysiloxane that is solid at 25 ° C. in an amount of (AI) / (A-II) = 17 / 83-80 / 20 by weight unit,
(B): The following average composition formula (2)
R ¹ _a H _b SiO _{(4-ab) / 2} (2)
(Wherein R ¹ is a substituted or unsubstituted monovalent hydrocarbon group excluding an aliphatic unsaturated hydrocarbon group, a and b are 0.7 ≦ a ≦ 2.1 and 0.01 ≦ b ≦ 1.0. And a positive number satisfying 0.8 ≦ a + b ≦ 2.9)
A linear organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in one molecule and having a viscosity at 25 ° C. of 1000 mPas or less, the number of hydrogen atoms bonded to the silicon atom Is an amount such that 0.3 to 10 per one total number of silicon-bonded alkenyl groups in the components (AI) and (A-II),
(C): addition reaction catalyst A curable organopolysiloxane composition containing a catalytic amount. Wherein (A-I), (A -II) and each component of (B) is curable organo according to claim 1, characterized in that it comprises at least one silicon bonded aryl group per molecule Polysiloxane composition. A semiconductor device, wherein a semiconductor element is coated with a cured product of the curable organopolysiloxane composition according to claim 1 . The semiconductor device according to claim 3 , wherein the semiconductor element is a light emitting element.

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