JP7121735B2 - Curable silicone composition, light-reflecting material comprising the same, and method for producing the same - Google Patents

Description

The present invention relates to a curable silicone composition, preferably a curable granular silicone composition and moldings thereof (such as pellets). Furthermore, the present invention relates to a cured product such as the curable silicone composition, a method for molding the cured product, a light reflecting material comprising the cured product, and a semiconductor device comprising the cured product.

Curable silicone compositions are used in a wide range of industrial fields because they cure to form cured products with excellent heat resistance, cold resistance, electrical insulation, weather resistance, water repellency, and transparency. A cured product of such a curable silicone composition is more resistant to discoloration than other organic materials, and has less deterioration in physical properties, making it suitable as an optical material.

The present applicant has proposed so-called hot-melt curable granular silicone compositions and reactive silicone compositions in Patent Documents 1 and 2. However, cured products obtained by curing these silicone compositions sometimes lack flexibility and toughness, especially at high temperatures from room temperature to about 150°C. In addition, these documents hardly mention the wavelength dependence of light reflectance in the visible light region, and do not disclose materials having high light reflectance in thin films.

The present applicant also proposed a liquid (paste) curable silicone composition in Patent Documents 3 and 4. However, these liquid or paste curable silicone compositions are not sufficient in handling workability, curing characteristics and gap-filling properties, and the cured products lack flexibility and toughness at high temperatures from room temperature to about 150°C. In particular, due to insufficient flexibility of the cured product, problems such as warpage and breakage may occur.

On the other hand, Patent Documents 5 and 6 disclose a hot-melt curable composition using a mixed filler containing coarse particles, but the cured product has an extremely high storage modulus at room temperature (e.g., In Patent Document 5, it is 5000 MPa or more), and since it lacks flexibility, it is difficult to apply it to applications that are subject to deformation and bending at room temperature. In addition, warping after integral molding with the lead frame is suppressed by reducing the coefficient of linear expansion due to high filling of the filler, so a large amount of white pigment cannot be added. Therefore, these inventions have the problem that high reflectance cannot be achieved in thin films.

International patent application PCT/JP2016/000959 JP 2014-009322 A International Publication No. 2016/038836 pamphlet JP 2013-076050 A JP 2013-221075 A International Publication No. 2013/051600 pamphlet

In addition to the above problems, the inventors found a new problem. Known hot-melt curable silicone compositions are generally heated and melted at 100 to 180° C. in the industry. Sufficient fluidity and gap-filling properties cannot be achieved when injected, and a cured product having a desired shape may not be obtained. On the other hand, the melt viscosity of such a hot-melt curable silicone composition can be adjusted to some extent by selecting the hot-melt silicone, but when using a hot-melt silicone with high fluidity at high temperatures, The flexibility and toughness of the cured product may be insufficient at high temperatures, and it may cause poor adhesion of the cured product. Therefore, while using a hot-melt silicone optimized to give a cured product with excellent flexibility, toughness and adhesiveness even at high temperatures, the melt viscosity of the composition is greatly reduced and sufficient There is a need for techniques that provide fluidity and gap fill.

An object of the present invention is to have hot-melt properties, to be able to achieve sufficient fluidity and gap-filling properties during heating and melting, and to have excellent handling workability and adhesiveness of the cured product, and a temperature range from room temperature to 150 ° C. The object of the present invention is to provide a curable silicone composition that gives a cured product with excellent flexibility and toughness at moderately high temperatures, and to provide pellets and the like obtained by molding this curable silicone composition. Another object of the present invention is to provide a light reflecting material comprising such a curable silicone composition and a cured product such as pellets, an optical semiconductor device having the cured product, and a method for molding the cured product. .

The curable silicone composition of the present invention is
(A0) a hot-melt silicone having a curable functional group;
(B) an inorganic filler having an average particle size of 1.0 μm or less;
(C0) a hot-melt component (excluding components corresponding to (A0) component) and (D) a curing agent, and
The kinematic viscosity (Vis _A ) of component (A0) when melted at 150° C. and the kinematic viscosity (Vis _C ) of component (C0) when melted at 150° C. are characterized in that Vis _A >Vis _C. Preferably, the above Vis _A is in the range of 1 to 2,000 Pa s, Vis _C is 1/5 or less of Vis _A , and (A0) component, (B) component, and (D) component When the sum is 100 parts by mass, the content of component (C0) is in the range of 0.01 to 5.0 parts by mass.

More preferably, the component (A0) of the composition is (A) hot-melt silicone fine particles having a softening point of 30° C. or higher and having a hydrosilylation-reactive group and/or a radical-reactive group, and (B ) is 90% by mass or more of (B1) titanium oxide fine particles having an average particle size in the range of 0.10 to 0.75 μm, and (C0) is a hot-melt component consisting of (C) fatty acid metal salt. be.

Furthermore, the component (C0) is preferably (C1) a fatty acid metal salt having a free fatty acid content of 5.0% or less, and particularly preferably contains at least one metal stearate.

The component (A0) comprises (A ₁ ) a resinous organopolysiloxane, (A ₂ ) a crosslinked organopolysiloxane obtained by partially crosslinking at least one organopolysiloxane, and (A ₃ ) a resinous organosiloxane block. and a chain-like organosiloxane block, or silicone fine particles comprising a mixture of at least two of these. It is particularly preferred that the particles are true spherical silicone microparticles having an average primary particle diameter of 1 to 10 μm.

The composition may be in the form of a granular composition and may be molded into pellets or sheets.

The curable silicone composition of the present invention can be used in the form of a cured product, and can be used as light reflectors and members of optical semiconductor devices.

The curable silicone composition of the present invention and its cured product can be used in an optical semiconductor device, and an optical semiconductor device is provided in which a light reflecting material is formed from the cured product. In particular, the present invention suitably provides a chip scale package type optical semiconductor device in which the wall thickness of the light reflecting material is thin.

The molding method of the curable granular silicone composition of the present invention includes at least the following steps.
(I) heating the curable granular silicone composition above the softening point of component (A0) to melt;
(II) A step of injecting the curable silicone composition obtained in step (I) into a mold, or a step of spreading the curable silicone composition obtained in step (I) over the mold by clamping the mold. and (III) a step of curing the curable silicone composition injected in step (II) above, wherein the molding method includes transfer molding, compression molding, or injection molding, and the curable silicone composition of the present invention. is suitably used as a material for these moldings.

The curable silicone composition (including pellets) of the present invention has hot-melt properties, is capable of achieving sufficient fluidity and gap-filling properties when heated and melted, and is easy to handle and has adhesive properties. It gives a cured product with excellent flexibility and toughness at high temperatures from room temperature to about 150°C. In addition, the cured product of the present invention can have a high light reflectance in the visible wavelength region by selecting an inorganic filler, and is useful as a light reflecting material and a member of an optical semiconductor device, and the molding method of the present invention can be used. Therefore, these cured products can be produced efficiently according to the intended use.

[Curable silicone composition]
The curable silicone composition of the present invention comprises the following components (A0), (B), (C0) and (D), and when component (A0) melts at 150°C The kinematic viscosity (Vis _A ) of component (C0) and the kinematic viscosity (Vis _C ) of component (C0) when melted at 150° C. are characterized in that Vis _A >Vis _C.
(A0) a hot-melt silicone having a curable functional group;
(B) an inorganic filler having an average particle size of 1.0 μm or less;
(C0) hot-melt component (excluding components corresponding to (A0) component), and (D) curing agent

The composition has heat-meltability (hot-melt property) and curability, and preferably provides a cured product having flexibility from room temperature to high temperature upon curing and high light reflectance in the visible wavelength region. can give. In addition, the properties of the curable silicone composition are not particularly limited, and can be obtained by semi-curing a solid composition, semi-solid composition, granular composition, or paste composition intended to be melted by heating. Although it may be a solid composition, a granular composition is particularly preferred from the standpoint of productivity and handling workability.
Each component and optional components of the composition are described below.

[(A0) component: hot-melt silicone]
Component (A0) is a silicone having a curable functional group that imparts good hot-melt properties to the composition, and is cured by component (D), which will be described later. In relation to the (C0) component described later, such a (A0) component has a structure when the kinematic viscosity (Vis _A ) when the component is melted at 150 ° C. is greater than that of the (C0) component. and functional groups are not particularly limited, but those having a Vis _A in the range of 1 to 2,000 Pa s are preferably used from the standpoint of fluidity and gap-filling properties during hot-melt of the composition. be done. Further, when a high-temperature curing reaction is employed, the curable functional group is preferably one or more selected from hydrosilylation-reactive groups and radical-reactive groups. Can be hot melt silicone with any curing reactive functional groups

Such a component (A0) may be a solid, semi-solid, particulate, or paste-like composition that is semi-cured into a solid. is preferably a hot-melt silicone. Component (A0) is particularly preferably (A) hot-melt silicone fine particles having a softening point of 30° C. or higher and having a hydrosilylation-reactive group and/or a radical-reactive group.

The hydrosilylation-reactive group in component (A0) includes vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, and dodecenyl groups. Alkenyl groups from 2 to 20, and silicon-bonded hydrogen atoms are exemplified. An alkenyl group is preferred as the hydrosilylation-reactive group. This alkenyl group may be linear or branched, preferably a vinyl group or a hexenyl group. Component (A0) preferably has at least two hydrosilylation-reactive groups in one molecule.

Silicon-bonded groups other than hydrosilylation-reactive groups in component (A0) include alkyl groups having 1 to 20 carbon atoms, halogen-substituted alkyl groups having 1 to 20 carbon atoms, and aryl groups having 6 to 20 carbon atoms. , halogen-substituted aryl groups having 6 to 20 carbon atoms, aralkyl groups having 7 to 20 carbon atoms, alkoxy groups, and hydroxyl groups. Specifically, alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group; phenyl group, tolyl group; , xylyl group, naphthyl group, anthracenyl group, phenanthryl group, pyrenyl group and other aryl groups; phenethyl group, phenylpropyl group and other aralkyl groups; , a group substituted with a halogen atom such as a bromine atom; and an alkoxy group such as a methoxy group, an ethoxy group and a propoxy group. A phenyl group and a hydroxyl group are particularly preferred.

Radical reactive groups in component (A0) include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group and dodecyl group. Alkyl groups having 1 to 20 carbon atoms such as vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, and dodecenyl groups having 2 to 20 carbon atoms. acrylic-containing groups such as 3-acryloxypropyl group and 4-acryloxybutyl group; methacryl-containing groups such as 3-methacryloxypropyl group and 4-methacryloxybutyl group; and silicon-bonded hydrogen atoms. be done. An alkenyl group is preferred as the radical reactive group. This alkenyl group may be linear or branched, preferably a vinyl group or a hexenyl group. Component (A0) preferably has at least two radical reactive groups in one molecule.

Silicon-bonded groups other than radical-reactive groups in component (A0) include halogen-substituted alkyl groups having 1 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms, and halogen-substituted aryl groups having 6 to 20 carbon atoms. groups, aralkyl groups having 7 to 20 carbon atoms, alkoxy groups, and hydroxyl groups, and the same groups as those mentioned above are exemplified. A phenyl group and a hydroxyl group are particularly preferred. In particular, it is preferable that 10 mol % or more of all organic groups in the molecule of component (A) be aryl groups, particularly phenyl groups.

Component (A0) itself has hot-melt properties and cures in the presence of (D) curing agent. Such a (A) component is
(A ₁ ) resinous organopolysiloxane,
(A ₂ ) a crosslinked organopolysiloxane obtained by crosslinking at least one organopolysiloxane;
(A ₃ ) a block copolymer consisting of a resinous organosiloxane block and a linear organosiloxane block;
or a mixture of at least two of these.

Component (A ₁ ) is a resinous organopolysiloxane having a hydrosilylation-reactive group and/or a radical-reactive group, having many T units or Q units, and a hot-melt resinous organopolysiloxane having an aryl group. Siloxane is preferred. Examples of such (A ₁ ) components include triorganosiloxy units (M units) (organo groups are methyl groups only, methyl groups and vinyl groups, or phenyl groups), diorganosiloxy units (D units) (organo groups are methyl groups only, methyl groups and vinyl groups or phenyl groups.), monoorganosiloxy units (T units) (organo groups are methyl, vinyl or phenyl groups) and siloxy units (Q units ) are exemplified by MQ resins, MDQ resins, MTQ resins, MDTQ resins, TD resins, TQ resins, and TDQ resins. The component (A ₁ ) has at least two hydrosilylation-reactive groups and/or radical-reactive groups in the molecule, and 10 mol % or more of all organic groups in the molecule are aryl groups, particularly phenyl groups. It is preferably a group.

In addition, since component (A ₂ ) is obtained by cross-linking at least one type of organopolysiloxane, cracks are less likely to occur during curing with the curing agent (D), and curing shrinkage can be reduced. Here, the term "crosslinking" means linking organopolysiloxanes by hydrosilylation reaction, condensation reaction, radical reaction, high-energy ray reaction, or the like. Examples of the hydrosilylation-reactive groups and radical-reactive groups (including high-energy ray-reactive groups) include the same groups as those described above, and examples of condensation-reactive groups include hydroxyl groups, alkoxy groups, and acyloxy groups. be done.

The units constituting the component (A ₂ ) are not limited, and examples thereof include siloxane units and silalkylene group-containing siloxane units. It is preferable to have a resinous polysiloxane unit and a chain polysiloxane unit in the. That is, the (A ₂ ) component is preferably a crosslinked product of a resinous organopolysiloxane and a chain (including linear or branched) organopolysiloxane. By introducing the resinous organopolysiloxane structure-chain organopolysiloxane structure into the component (A ₂ ), the component (A ₂ ) exhibits good hot-melt properties, and the (D) curing agent Curability is shown.

(A ₂ ) The component is
(1) Through the hydrosilylation reaction of an organopolysiloxane having at least two alkenyl groups in one molecule and an organopolysiloxane having at least two silicon-bonded hydrogen atoms in one molecule, a resinous organopolysiloxane is obtained in the molecule. A siloxane structure-a chain organopolysiloxane structure linked by an alkylene bond (2) through a radical reaction with an organic peroxide of at least two organopolysiloxanes having at least two radically reactive groups in one molecule , a resinous organopolysiloxane structure in the molecule-a chain organopolysiloxane structure linked by a siloxane bond or an alkylene bond; Siloxane structure—Any chain organopolysiloxane structure linked by siloxane (--Si--O--Si--) bonds. Such a component (A ₂ ) has a structure in which the organopolysiloxane portion of the resin structure-chain structure is linked by an alkylene group or a new siloxane bond, so the hot-melt property is remarkably improved.

In (1) and (2) above, examples of the alkylene group contained in component (A ₂ ) include alkenyl groups having 2 to 20 carbon atoms, such as ethylene, propylene, butylene, pentylene, and hexylene. These may be linear or branched, preferably ethylene or hexylene.

A crosslinked product of a resinous organopolysiloxane and a chain (including linear or branched) organopolysiloxane is composed of, for example, the following siloxane units and silalkylene group-containing siloxane units.
M unit: a siloxane unit represented by R ¹ R ² ₂ SiO _1/2 ,
D unit: a siloxane unit represented by R ¹ R ² SiO _2/2 ,
R ³ M/R ³ D units: Silalkylene group-containing siloxane units represented by R ³ _1/2 R ² ₂ SiO _1/2 and silalkylene groups represented by R ³ _1/2 R ² SiO _2/2 At least one siloxane unit selected from siloxane units contained, and at least one siloxane selected from siloxane units represented by T/Q units: R ² SiO _3/2 and SiO _4/2 unit

In the formula, each R ¹ is independently an alkyl group having 1 to 20 carbon atoms, a halogen-substituted alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a carbon It is a halogen-substituted aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, and the same groups as those mentioned above are exemplified. R ¹ is preferably a methyl group, a vinyl group or a phenyl group. However, it is preferable that at least two ^R1 's among all siloxane units are alkenyl groups.

In the formula, each R ² is independently an alkyl group having 1 to 20 carbon atoms, a halogen-substituted alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and a halogen-substituted group having 6 to 20 carbon atoms. It is an aryl group or an aralkyl group having 7 to 20 carbon atoms, and is exemplified by the same groups as those for R ¹ above. R ² is preferably a methyl group or a phenyl group.

In the formula, R ³ is a linear or branched C 2-20 alkylene group bonded to the silicon atom in another siloxane unit. The alkylene group is exemplified by the same groups as those mentioned above, with ethylene group and hexylene group being preferred.

The M unit is a siloxane unit that constitutes the terminal of component (A ₂ ), and the D unit is a siloxane unit that constitutes a linear polysiloxane structure. It is preferred that these M units or D units, especially M units, have an alkenyl group. On the other hand, R ³ M units and R ³ D units are siloxane units that are bonded to silicon atoms in other siloxane units via silalkylene bonds and to silicon atoms in other siloxane units via oxygen atoms. is. The T/Q units are branched siloxane units that give the polysiloxane a resin-like structure, and the (A ₂ ) component is represented by siloxane units represented by R ² SiO _3/2 and/or SiO _4/2 . It preferably contains siloxane units. In particular, the component (A ₂ ) is a siloxane represented by R ² SiO _3/2 because it improves the hot-melt properties of the component (A ₂ ) and adjusts the content of aryl groups in the component (A ₂ ). It preferably contains a unit, particularly preferably a siloxane unit in which R ² is a phenyl group.

The R ³ M/R ³ D unit is one of the characteristic structures of the (A ₂ ) component, and represents a structure in which silicon atoms are bridged via the alkylene group of R ³ . Specifically, it is selected from alkylene group-containing siloxane units represented by R ³ _1/2 R ² ₂ SiO _1/2 and alkylene group-containing siloxane units represented by R ³ _1/2 R ² SiO _2/2 At least one siloxane unit, and at least two of all siloxane units constituting the component (A ₂ ) are preferably these alkylene group-containing siloxane units. The preferred form of bonding between siloxane units having an alkylene group for R ³ is as described above, and the number of R ³ between two alkylene group-containing siloxane units is a bond valence of "1/ 2” is expressed. If the number of R ³ is 1, [O _1/2 R ² ₂ SiR ³ SiR ² ₂ O _1/2 ], [O _1/2 R ² ₂ SiR ³ SiR ² O _2/2 ] and [O _2/2 R ² SiR ³ SiR ² O _2/2 ] is contained in the component (A ₂ ), and each oxygen atom (O) is the above M , D, and the silicon atoms contained in the T/Q units. By having such a structure, the (A ₂ ) component can relatively easily design a structure having a chain polysiloxane structure consisting of D units and a resinous polysiloxane structure containing T/Q units in the molecule. , which is remarkably superior in its physical properties.

In the above (1), an organopolysiloxane having at least two alkenyl groups in one molecule and an organopolysiloxane having at least two silicon-bonded hydrogen atoms in one molecule are divided into [number of moles of alkenyl groups]/ It can be obtained by a hydrosilylation reaction at a reaction ratio of [number of moles of silicon-bonded hydrogen atoms]>1.

In (2) above, at least two kinds of organopolysiloxanes having at least two radically reactive groups in one molecule are combined with an organic peroxide in an amount insufficient for all the radically reactive groups in the system to react. It can be obtained by radical reaction with substances.

In (1) and (2) above, the component (A ₂ ) is obtained by subjecting an organopolysiloxane having a resinous siloxane structure and an organopolysiloxane having a chain siloxane structure to a hydrosilylation reaction or a radical reaction.

For example, the (A ₂ ) component is
(A ^R ) a siloxane unit represented by R ² SiO _3/2 (wherein R ² is the same group as defined above) and/or a siloxane unit represented by SiO _4/2 in the molecule; at least one resinous organopolysiloxane containing an alkenyl group having 2 to 20 carbon atoms or a silicon-bonded hydrogen atom or a radical-reactive group, and (A ^L ) R ² ₂ SiO in the molecule A group containing a siloxane unit represented by _2/2 (wherein R ² is the same group as defined above) and capable of undergoing a hydrosilylation reaction or a radical reaction with the component (A ^R ) at least one linear organopolysiloxane having an alkenyl group having 2 to 20 carbon atoms or a silicon-bonded hydrogen atom,
It is an organopolysiloxane obtained by reacting at a ratio designed so that the hydrosilylation-reactive groups and/or radical-reactive groups in the (A ^R ) component or (A ^L ) component remain after the reaction.

In the above (1), when at least part of the (A ^R ) component is a resinous organopolysiloxane having an alkenyl group having 2 to 20 carbon atoms, at least part of the (A ^L ) component is silicon-bonded hydrogen A chain organopolysiloxane having atoms is preferred.

Similarly, when at least part of the (A ^R ) component is a resinous organopolysiloxane having silicon-bonded hydrogen atoms, at least part of the (A ^L ) component has an alkenyl group having 2 to 20 carbon atoms. A chain organopolysiloxane is preferred.

Such a (A ₂ ) component is
Component (a ₁ ): Organic peroxide of an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule, consisting of the following component (a _1-1 ) and/or the following component (a _1-2 ) radically reacted with a substance, or (a ₁ ) component,
(a ₂ ) organohydrogenpolysiloxane,
In the presence of a hydrosilylation reaction catalyst, the molar ratio of silicon-bonded hydrogen atoms in component (a ₂ ) to alkenyl groups having 2 to 20 carbon atoms contained in component (a ₁ ) is 0. It is preferable to hydrosilylate in an amount of 0.2 to 0.7 mol. These reactions may be carried out independently, or may be carried out in situ as a blend in the presence of the components (B), (C0) and (D), which will be described later. When the same component (D) is used for the synthesis of component (A0) and the curing reaction of the present composition, the composition becomes a so-called "semi-cured" state, and is not used during semi-curing in curing of the present composition. The curable functional groups in the composition and the remaining (D) component will be used.

Component (a _1-1 ) is a polysiloxane having a relatively large amount of branched units, and has an average unit formula:
(R43SiO1/ ² ) _a (R42SiO2 _/2 ) _b ( _{R4SiO3 /2 ) c} ⁽ _SiO4/2 ⁾ _d ⁽ _R5O1 / ₂ ) _e
It is an organopolysiloxane having at least two alkenyl groups in one molecule represented by the following. In the formula, each R ⁴ is independently an alkyl group having 1 to 20 carbon atoms, a halogen-substituted alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a carbon It is a halogen-substituted aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, and the same groups as those for R ¹ are exemplified. ^R4 is preferably a methyl group, a vinyl group, or a phenyl group. However, at least two of R ⁴ are alkenyl groups. Further, it is preferable that 10 mol % or more, or 20 mol % or more of all R ⁴ is a phenyl group, because the hot-melt property is good. In the formula, R ⁵ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and the same alkyl groups as those mentioned above are exemplified.

Further, in the formula, a is a number within a range of 0 to 0.7, b is a number within a range of 0 to 0.7, c is a number within a range of 0 to 0.9, and d is a number within a range of 0 to 0.7. a number within the range of 7, e is a number within the range of 0 to 0.1, and c + d is a number within the range of 0.3 to 0.9, a + b + c + d is 1, preferably a is 0 to a number within the range of 0.6, b is a number within the range of 0 to 0.6, c is a number within the range of 0 to 0.9, d is a number within the range of 0 to 0.5, e is A number within the range of 0 to 0.05, and c+d is a number within the range of 0.4 to 0.9, and a+b+c+d is 1. This is because when a, b, and c+d are numbers within the above ranges, the resulting cured product has excellent hardness and mechanical strength.

Examples of such (a _1-1 ) component include the following organopolysiloxanes. In the formula, Me, Ph and Vi represent a methyl group, a phenyl group and a vinyl group, respectively.
(ViMe2SiO1/ ₂ ) _0.25 ( _{PhSiO3 /2} ) _0.75 ( _HO1 /2) _0.02
(ViMe2SiO1/ ₂ ) _0.25 ( _{PhSiO3 /2} ) _0.75
(ViMe2SiO1/ ₂ ) _0.20 ( _{PhSiO3 /2} ) _0.80
(ViMe2SiO1/ ₂ ) _0.15 ( _Me3SiO1 / ₂ ) _0.38 ( _SiO4/2 ) _0.47 ( _HO1 / ₂ ) _0.01
(ViMe2SiO1/ ₂ ) _0.13 ( _Me3SiO1 / ₂ ) _0.45 ( _SiO4/2 ) _0.42 ( _HO1 / ₂ ) _0.01
(ViMe2SiO1/ ₂ ) _0.15 ( _{PhSiO3 /2} ) _0.85 ( _HO1 /2) _0.01
(Me2SiO2/ ₂ ) _0.15 ( _{MeViSiO2 /2} ) _0.10 (PhSiO3/ ₂ ) _0.75 ( _HO1 /2) _0.04
(MeViPhSiO1 _/2 ) _0.20 (PhSiO3/ ₂ ) _0.80 ( _HO1 /2) _0.05
(ViMe2SiO1/ ₂ ) _0.15 ( _{PhSiO3 /2} ) _0.75 ( _SiO4/2 ) _0.10 ( _HO1 /2) _0.02
(Ph2SiO2/ ₂ ) _0.25 ( _{MeViSiO2 /2} ) _0.30 (PhSiO3/ ₂ ) _0.45 ( _HO1 /2) _0.04
(Me3SiO1 _{/ 2} ) _0.20 ( _ViMePhSiO1 /2) _0.40 ( _SiO4/2 ) _0.40 ( _HO1 /2) _0.08

Component (a _1-2 ) is a polysiloxane having a relatively large amount of chain siloxane units, and has an average unit formula:
(R ⁴ ₃ SiO _1/2 ) _a' (R ⁴ ₂ SiO _2/2 ) _b' (R ⁴ SiO _3/2 ) _c' (SiO _4/2 ) _d' (R ⁵ O _1/2 ) _e'
It is an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in one molecule, represented by ^In the formula, ^R4 and R5 are the same groups as above.

In the formula, a' is a number within the range of 0.01 to 0.3, b' is a number within the range of 0.4 to 0.99, and c' is a number within the range of 0 to 0.2. , d′ is a number in the range 0 to 0.2, e′ is a number in the range 0 to 0.1, and c′+d′ is a number in the range 0 to 0.2, a′+b '+c'+d' is 1, preferably a' is a number in the range of 0.02 to 0.20, b' is a number in the range of 0.6 to 0.99, c' is 0 to a number within the range of 0.1, d' is a number within the range of 0 to 0.1, j' is a number within the range of 0 to 0.05, and c'+d' is a number within the range of 0 to 0.1 A number in the range a′+b′+c′+d′ is one. This is because when a', b', c', and d' are numbers within the above ranges, toughness can be imparted to the obtained cured product.

Examples of such (a _1-2 ) component include the following organopolysiloxanes. In the formula, Me, Ph and Vi represent a methyl group, a phenyl group and a vinyl group, respectively.
ViMe2SiO( _MePhSiO ) _18SiMe2Vi : (ViMe2SiO1/ ₂ ) _0.10 ( _{MePhSiO2 /2 ) 0.90}
ViMe2SiO( _MePhSiO ) _30SiMe2Vi : (ViMe2SiO1/ ₂ ) _0.063 ( _{MePhSiO2 /2 ) 0.937}
ViMe2SiO( _MePhSiO ) _150SiMe2Vi : (ViMe2SiO1/ ₂ ) _0.013 ( _{MePhSiO2 /2 ) 0.987}
ViMe2SiO( _Me2SiO ) _18SiMe2Vi , i.e. ( _{ViMe2SiO1/2 ) 0.10 ( Me2SiO2 /2 ) 0.90}
ViMe2SiO( _Me2SiO ) _30SiMe2Vi : ( _{ViMe2SiO1/2 ) 0.063 ( Me2SiO2 /2 ) 0.937}
ViMe2SiO(Me2SiO) ₃₅ (MePhSiO) _13SiMe2Vi : ( _{ViMe2SiO1/2 ) 0.04} ( _{Me2SiO2 /2 ) 0.70} ( _{MePhSiO2 /2 ) 0.26}
ViMe2SiO( _Me2SiO ) _10SiMe2Vi , i.e. ( _{ViMe2SiO1/2 ) 0.17 ( Me2SiO2 /2 ) 0.83}
(ViMe2SiO1/ ₂ ) _0.10 (MePhSiO2 _/2 ) _0.80 ( _PhSiO3 / ₂ ) _0.10 ( _HO1 /2) _0.02
(ViMe2SiO1/ ₂ ) _0.20 ( _{MePhSiO2 /2} ) _0.70 ( _SiO4/2 ) _0.10 ( _HO1 /2) _{0.01
HOMe2SiO} ( _MeViSiO ) _{20SiMe2OH
Me2ViSiO} ( _MePhSiO ) _{30SiMe2Vi
Me2ViSiO ( Me2SiO} ) _150SiMe2Vi

The component (a _1-1 ) is preferably used from the viewpoint of imparting hardness and mechanical strength to the resulting cured product. Component ₍ a _1-2 ) can be added as an optional component from the viewpoint of imparting toughness to the resulting cured product. can be substituted with In any case, the mass ratio of the component having many branched siloxane units and the component having many chain siloxane units is within the range of 50:50 to 100:0, or within the range of 60:40 to 100:0. Preferably. This is because when the mass ratio of the component having many branched siloxane units and the component having many chain siloxane units is within the above range, the resulting cured product has good hardness and mechanical strength. be.

When component (a ₁ ) undergoes a radical reaction with an organic peroxide, component (a _1-1 ) and component (a _1-2 ) are reacted within the range of 10:90 to 90:10, ( a ₂ ) component may not be used.

Component (a ₂ ) is a component for crosslinking component (a _1-1 ) and/or component (a _1-2 ) in the hydrosilylation reaction, and contains at least two silicon-bonded hydrogen atoms in one molecule. It is an organopolysiloxane containing Silicon-bonded groups other than hydrogen atoms in component (a ₂ ) include alkyl groups having 1 to 20 carbon atoms, halogen-substituted alkyl groups having 1 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms, Examples include halogen-substituted aryl groups having 6 to 20 carbon atoms, aralkyl groups having 7 to 20 carbon atoms, alkoxy groups, epoxy group-containing groups, and hydroxyl groups, and the same groups as those described above.

Such (a ₂ ) component is not limited, but preferably has the average compositional formula:
R ⁶ _k H _m SiO _(4-km)/2
is an organohydrogenpolysiloxane represented by In the formula, R ⁶ is an alkyl group having 1 to 20 carbon atoms, a halogen-substituted alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a halogen-substituted aryl group having 6 to 20 carbon atoms, or a carbon number It is an aralkyl group of 7 to 20 and is exemplified by the same groups as those for R ¹ above, preferably a methyl group or a phenyl group.

Further, in the formula, k is a number in the range of 1.0 to 2.5, preferably in the range of 1.2 to 2.3, m is a number in the range of 0.01 to 0.9, Preferably, it is a number in the range 0.05 to 0.8 and k+m is a number in the range 1.5 to 3.0, preferably in the range 2.0 to 2.7.

The component (a ₂ ) may be a resinous organohydrogenpolysiloxane having many branched siloxane units, or a chain organohydrogenpolysiloxane having many chain siloxane units. Specifically, component (a ₂ ) is an organohydrogenpolysiloxane represented by (a _2-1 ) below, an organohydrogenpolysiloxane represented by (a _2-2 ) below, or a mixture thereof. is exemplified.

The (a _2-1 ) component has the average unit formula:
[R ⁷ ₃ SiO _1/2 ] _f [R ⁷ ₂ SiO _2/2 ] _g [R ⁷ SiO _3/2 ] _h [SiO _4/2 ] _i (R ⁵ O _1/2 ) _j
is a resinous organohydrogenpolysiloxane having silicon-bonded hydrogen atoms represented by In the formula, each R ⁷ is independently an alkyl group having 1 to 20 carbon atoms, a halogen-substituted alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and a halogen-substituted aryl group having 6 to 20 carbon atoms. , an aralkyl group having 7 to 20 carbon atoms, or a hydrogen atom, and the same groups as those for R ¹ are exemplified. Further, in the formula, R ⁵ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and the same groups as those mentioned above are exemplified.

Further, in the formula, f is a number within a range of 0 to 0.7, g is a number within a range of 0 to 0.7, h is a number within a range of 0 to 0.9, i is 0 to 0.9. a number within the range of 7, j is a number within the range of 0 to 0.1, and h+i is a number within the range of 0.3 to 0.9, f + g + h + i is 1, preferably f is 0 to a number within the range of 0.6, g is a number within the range of 0 to 0.6, h is a number within the range of 0 to 0.9, i is a number within the range of 0 to 0.5, j is A number within the range of 0 to 0.05, h+i is a number within the range of 0.4 to 0.9, and f+g+h+i is 1.

The (a _2-2 ) component has the average unit formula:
( ^R73SiO1 _{/2 ) f'} ( ^R72SiO2 / ₂ ) _g' ( _{R7SiO3 /2} ⁾ _h' ( _SiO4/2 ) _i' ( ^R5O1 / ₂ ) _j'
It is an organopolysiloxane having at least two silicon-bonded hydrogen atoms in one molecule, represented by: ^In the formula, ^R7 and R5 are the same groups as above.

In the formula, f' is a number within the range of 0.01 to 0.3, g' is a number within the range of 0.4 to 0.99, and h' is a number within the range of 0 to 0.2. , i′ is a number in the range of 0 to 0.2, j′ is a number in the range of 0 to 0.1, and h′+i′ is a number in the range of 0 to 0.2, f′+g '+h'+i' is 1, preferably f' is a number in the range of 0.02 to 0.20, g' is a number in the range of 0.6 to 0.99, h' is 0 to a number within the range of 0.1, i' is a number within the range of 0 to 0.1, j' is a number within the range of 0 to 0.05, and h'+i' is a number within the range of 0 to 0.1 A number in the range, f'+g'+h'+i', is one.

As described above, in the component (a ₂ ), the resinous organopolysiloxane having many branched siloxane units imparts hardness and mechanical strength to the cured product, and the obtained organopolysiloxane having many chain siloxane units (a _2-1 ) and (a _2-2 ) are preferably used as the (a ₂ ) component, since it imparts toughness to the cured product. Specifically, when component (a ₁ ) contains few branched siloxane units, component (a _2-1 ) is preferably used as component ( _{a 2} ). When the number of chain siloxane units is small, it is preferable to mainly use component (a _2-2 ). Component (a ₂ ) has a mass ratio of component (a _2-1 ) to component (a _2-2 ) in the range of 50:50 to 100:0, or in the range of 60:40 to 100:0. is preferred.

Examples of such component (a ₂ ) include the following organopolysiloxanes. In the formula, Me and Ph represent a methyl group and a phenyl group, respectively.
Ph ₂ Si(OSiMe ₂ H) ₂ ie Ph _0.67 Me _1.33 H _0.67 SiO _0.67
HMe2SiO ( _Me2SiO ) _{20SiMe2H ie Me2.00 H0.09 SiO0.95
HMe2SiO ( Me2SiO ) 55SiMe2H ie Me2.00H0.04SiO0.98
PhSi} ( _{OSiMe2H ) 3} , _{i.e. Ph0.25Me1.50H0.75SiO0.75}
(HMe ₂ SiO _1/2 ) _0.6 (PhSiO _3/2 ) _0.4 ie Ph _0.40 Me _1.20 H _0.60 SiO _0.90

Component (a ₂ ) is added in such an amount that the molar ratio of silicon-bonded hydrogen atoms in component (a ₂ ) to alkenyl groups in component (a ₁ ) is 0.2 to 0.7. The amount is preferably 0.3 to 0.6. This is because when the amount of component (a ₂ ) added is within the above range, the initial hardness and mechanical strength of the resulting cured product are improved.

The organic peroxide used for the radical reaction of component (a ₁ ) is not limited, and organic peroxides exemplified below as component (D) can be used. In the radical reaction, the (a ₁ ) component is preferably a mixture in which the mass ratio of the (a _1-1 ) component and the (a _1-2 ) component is in the range of 10:90 to 90:10. The amount of the organic peroxide to be added is not limited, but is within the range of 0.1 to 5 parts by mass, within the range of 0.2 to ₃ parts by mass, or 0 It is preferably in the range of 0.2 to 1.5 parts by mass.

In addition, the hydrosilylation reaction catalyst used for the hydrosilylation reaction of the component (a ₁ ) and the component (a ₂ ) is not limited, and the hydrosilylation reaction catalysts exemplified for the component (D) below can be used. . The addition amount of the hydrosilylation reaction catalyst is 0.01 to 0.01 in terms of mass unit of the platinum-based metal atoms in the hydrosilylation reaction catalyst with respect to the total amount of the components (a ₁ ) and (a ₂ ). Preferably the amount is in the range of 500 ppm, in the range of 0.01 to 100 ppm, or in the range of 0.01 to 50 ppm.

The above (A ₃ ) is obtained by subjecting the following component (a ₃ ) and the following component (a ₄ ) to a condensation reaction using a condensation reaction catalyst.

The (a ₃ ) component has an average unit formula:
( ^R83SiO1 _{/2 ) p} ( ^R82SiO2 / ₂ ) _q ( _R8SiO3 / ₂ ) _r ⁽ _SiO4/2 ) _s ( ^R9O1 / ₂ ) _t
is a condensation-reactive organopolysiloxane represented by In the formula, each R ⁸ is independently an alkyl group having 1 to 20 carbon atoms, a halogen-substituted alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a carbon It is a halogen-substituted aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, and the same groups as those mentioned above are exemplified. R ⁹ in the formula is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an acyl group having 2 to 5 carbon atoms, and is exemplified by an alkoxy group such as a methoxy group and an ethoxy group; and an acyloxy group. Component (a ₃ ) has at least one silicon-bonded hydroxyl group, silicon-bonded alkoxy group, or silicon-bonded acyloxy group in one molecule. At least two R8's ⁱⁿ one molecule are alkenyl groups, and ¹⁰ mol% or more, or 20 mol% or more of all R8's are preferably phenyl groups.

In the formula, p is a number within the range of 0 to 0.7, q is a number within the range of 0 to 0.7, r is a number within the range of 0 to 0.9, and s is a number within the range of 0 to 0.7. a number within the range, t is a number within the range of 0.01 to 0.10, and r + s is a number within the range of 0.3 to 0.9, p + q + r + s is 1, preferably p is 0 to a number within the range of 0.6, q is a number within the range of 0 to 0.6, r is a number within the range of 0 to 0.9, s is a number within the range of 0 to 0.5, t is A number within the range of 0.01 to 0.05, and r+s is a number within the range of 0.4 to 0.9. This is because when p, q, and r + s are numbers within the above ranges, they have flexibility at 25 ° C., but are non-flowing, have low surface tackiness, and have sufficiently low melt viscosity at high temperatures. This is because hot-melt silicone can be obtained.

The (a ₄ ) component has the average unit formula:
(R ⁸ ₃ SiO _1/2 ) _p' (R ⁸ ₂ SiO _2/2 ) _q' (R ⁸ SiO _3/2 ) _r' (SiO _4/2 ) _s' (R ⁹ O _1/2 ) _t'
is a condensation-reactive organopolysiloxane represented by ^In the formula, R8 and ^R9 are the same groups as above. Component (a ₄ ) has at least one silicon-bonded hydroxyl group, silicon-bonded alkoxy group, or silicon-bonded acyloxy group in one molecule. In the formula, p' is a number within the range of 0.01 to 0.3, q' is a number within the range of 0.4 to 0.99, and r' is a number within the range of 0 to 0.2. , s′ is a number in the range 0 to 0.2, t′ is a number in the range 0 to 0.1, and r′+s′ is a number in the range 0 to 0.2, p′+q '+r'+s' is 1, preferably p' is a number in the range of 0.02 to 0.20, q' is a number in the range of 0.6 to 0.99, r' is 0 to a number within the range of 0.1, s' is a number within the range of 0 to 0.1, t' is a number within the range of 0 to 0.05, and r'+s' is a number within the range of 0 to 0.1 A number in the range. This is because when p', q', r', and s' are numbers within the above ranges, they have flexibility at 25 ° C., but are non-flowing, have low surface tackiness, and can be melted at high temperatures. This is because a hot-melt silicone having a sufficiently low viscosity can be obtained.

The condensation reaction catalyst for the condensation reaction of the component (a ₃ ) and the component (a ₄ ) is not limited, and examples thereof include dibutyltin dilaurate, dibutyltin diacetate, tin octate, dibutyltin dioctate, tin laurate, and the like. Organic tin compounds; organic titanium compounds such as tetrabutyl titanate, tetrapropyl titanate, dibutoxybis(ethylacetoacetate); other acidic compounds such as hydrochloric acid, sulfuric acid and dodecylbenzenesulfonic acid; alkaline compounds such as ammonia and sodium hydroxide; ,8-diazabicyclo[5.4.0]undecene (DBU), 1,4-diazabicyclo[2.2.2]octane (DABCO) and other amine compounds, preferably organotin compounds, organotitanium is a compound.

Also, the (A ₃ ) component is a block copolymer consisting of a resinous organosiloxane block and a chain organosiloxane block. Such (A ₃ ) component preferably comprises 40 to 90 mol % of disiloxy units of formula [R ¹ ₂ SiO _2/2 ], 10 to 60 mol % of trisiloxy units of formula [R ¹ SiO _3/2 ] It is preferably composed of units and contains 0.5 to 35 mol % of silanol groups [≡SiOH]. Here, each R ¹ is independently an alkyl group having 1 to 20 carbon atoms, a halogen-substituted alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a carbon It is a halogen-substituted aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, and the same groups as those mentioned above are exemplified. At least two R1's in ^one molecule are alkenyl groups. Further, the disiloxy unit [R ¹ ₂ SiO _2/2 ] forms a linear block having 100 to 300 disiloxy units on average per linear block, and the trisiloxy unit [R ¹ SiO _{3 /2} ] form non-linear blocks having a molecular weight of at least 500 g/mol, at least 30% of the non-linear blocks being linked to each other, each linear block linked to at least one non-linear block Resinous organosiloxanes bonded via —Si—O—Si— bonds, having a weight average molecular weight of at least 20 000 g/mol and containing 0.5 to 4.5 mol % of at least one alkenyl group It is a block copolymer.

Component (A ₃ ) is obtained by condensation reaction of (a ₅ ) resinous organosiloxane or resinous organosiloxane block copolymer, (a ₆ ) linear organosiloxane, and optionally (a ₇ ) siloxane compound. prepared by

The component (a ₅ ) has the average unit formula:
[R ¹ ₂ R ² SiO _1/2 ] _i [R ¹ R ² SiO _2/2 ] _ii [R ¹ SiO _3/2 ] _iii [R ² SiO _3/2 ] _iv [SiO _4/2 ] _v
is a resinous organosiloxane represented by In the formula, each R ¹ is independently an alkyl group having 1 to 20 carbon atoms, a halogen-substituted alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a carbon It is a halogen-substituted aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, and the same groups as those mentioned above are exemplified. In the formula, each R ² is independently an alkyl group having 1 to 20 carbon atoms, a halogen-substituted alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and a halogen-substituted group having 6 to 20 carbon atoms. It is an aryl group or an aralkyl group having 7 to 20 carbon atoms, and is exemplified by the same groups as those for R ¹ above.

Further, in the formula, i, ii, iii, iv, and v represent the mole fraction of each siloxy unit, i is a number from 0 to 0.6, and ii is a number from 0 to 0.6. , iii is a number from 0 to 1, iv is a number from 0 to 1, and v is a number from 0 to 0.6, provided that ii+iii+iv+v>0 and i+ii+iii+iv+v≦1. In addition, the component (a ₅ ) preferably contains 0 to 35 mol % of silanol groups [≡SiOH] in one molecule.

Component (a ₆ ) has the general formula:
R ¹ _3-α (X) _α SiO (R ¹ ₂ SiO) _β Si (X) _α R ¹ _3-α
It is a linear organosiloxane represented by. In the formula, R ¹ is the same as defined above, and the same groups as defined above are exemplified. In the formula, X is -OR ⁵ , F, Cl, Br, I, -OC(O)R ⁵ , -N(R ⁵ ) ₂ or -ON=CR ⁵ ₂ (where R ⁵ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms). In the formula, α is each independently 1, 2, or 3, and β is an integer of 50-300.

Component (a ₇ ) has the general formula:
R ¹ R ² ₂ SiX
is a siloxane compound represented by In the formula, R ¹ , R ² and X are the same groups as defined above.

The condensation reaction catalyst for the condensation reaction of the component ( _a5 ) with the component ( _a6 ) and/or the component ( _a7 ) is not limited. Organotin compounds such as tin dioctate and tin laurate; Organotitanium compounds such as tetrabutyl titanate, tetrapropyl titanate and dibutoxybis(ethylacetoacetate); Acidic compounds such as hydrochloric acid, sulfuric acid and dodecylbenzenesulfonic acid; Ammonia, water alkaline compounds such as sodium oxide; and amine compounds such as 1,8-diazabicyclo[5.4.0]undecene (DBU) and 1,4-diazabicyclo[2.2.2]octane (DABCO).

Component (A0) preferably exhibits hot-melt properties, specifically, is non-flowable at 25°C and has a melt viscosity of 8000 Pa·s or less at 100°C. Non-fluid means that it does not flow under no load. Indicates the state below the softening point measured by the test method. That is, in order to be non-flowable at 25°C, the softening point must be higher than 25°C. The melt viscosity means the kinematic viscosity (Pa·s) when melted at the temperature.

Component (A0) preferably has a melt viscosity at 100° C. of 8000 Pa·s or less, 5000 Pa·s or less, or in the range of 10 to 3000 Pa·s. When the melt viscosity at 100°C is within the above range, the adhesion after cooling to 25°C after hot-melting is good.

As described above, component (A0) needs to have a kinematic viscosity (Vis _A ) when melted at 150° C. greater than that of component (C0) in relation to component (C0), which will be described later. Any means can be used to measure the kinematic viscosity, but in the case of a high viscosity of 100 Pa·s or more, it is preferable to measure using a flow tester. If the kinematic viscosity is lower than this, it can be measured using a rotational viscometer or the like, but if the kinematic viscosity measured with a rotational viscometer is 1,000 Pa s or more, it will be more accurate than a flow tester. Kinematic viscosity may not be measured. From the standpoint of hot-melt fluidity and gap fill properties of the composition, the Vis _A measured by the above measuring method is 1 to 2,000 Pa s, 1 to 1,500 Pa s, 1 to 1,000 Pa s. It is preferably in the range of s. When the (C0) component consists essentially of one or more metal stearates, it is particularly preferred to use the (A0) component with a Vis _A in the range of 1 to 1,000 Pa·s. preferable.

The component (A0) may be a hot-melt solid, but is preferably in the form of fine particles. The particle size is not limited, but the average primary particle size is in the range of 1 to 5000 μm, 1 to 500 μm, 1 to 100 μm, 1 to 20 μm, or 1 to 10 μm. is preferred. This average primary particle size can be determined, for example, by observing with an optical microscope or SEM. The shape of component (A) is not limited, and may be spherical, spindle-shaped, plate-shaped, needle-shaped, or amorphous. In particular, by making the component (A) spherical with a size of 1 to 10 μm, the melting properties and mechanical properties of the composition after curing can be improved in some cases.

(A0) The method for producing the component is not limited, and a known method can be used. In the presence of components (B), (C0) and (D), which will be described later, in the case of in situ synthesis as a formulation, for example, after making a paste formulation by a known method, a desired heating step is performed. Component (A0) can be obtained by reacting so that unreacted component (D) remains.

In particular, when a finely divided component (A0) is used, a method of simply finely dividing the component (A0), or a step of cross-linking at least two kinds of organopolysiloxanes and a step of finely dividing the reactant thereof simultaneously or separately. There is a method to do it.

After cross-linking at least two kinds of organopolysiloxanes, the resulting silicone can be micronized, for example, by pulverizing the silicone with a pulverizer or by directly micronizing it in the presence of a solvent. is mentioned. Examples of the pulverizer include, but are not limited to, roll mills, ball mills, jet mills, turbo mills, and planetary mills. Examples of the method of directly atomizing the silicone in the presence of a solvent include spraying with a spray dryer, or atomization with a twin-screw kneader or belt dryer. In the present invention, the use of spherical hot-melt silicone fine particles obtained by spraying with a spray dryer is effective in improving the melting properties of the granular formulation, the flexibility of the cured product, the amount of component (B) blended, and the light reflectance. It is particularly preferred from the standpoint of improvement, efficiency during manufacture, and workability in handling the composition.

By using a spray dryer or the like, the component (A0) having a spherical shape and an average primary particle size of 1 to 500 μm can be produced. The heating/drying temperature of the spray dryer should be appropriately set based on the heat resistance of the silicone fine particles. In order to prevent secondary agglomeration of the silicone fine particles, it is preferable to control the temperature of the silicone fine particles below their glass transition temperature. The silicone microparticles thus obtained can be recovered with a cyclone, bag filter or the like.

For the purpose of obtaining a uniform component (A0), a solvent may be used in the above process within a range that does not inhibit the curing reaction. Solvents are not limited, but aliphatic hydrocarbons such as n-hexane, cyclohexane, and n-heptane; aromatic hydrocarbons such as toluene, xylene, and mesitylene; ethers such as tetrahydrofuran and dipropyl ether; Silicones such as methyltrisiloxane and decamethyltetrasiloxane; esters such as ethyl acetate, butyl acetate and propylene glycol monomethyl ether acetate; and ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone.

[(B) component: inorganic filler]
The component (B) of the present invention is an inorganic filler having an average particle size of 1.0 μm or less, and when used in combination with the component (C0), the composition exhibits high fluidity and gap-filling properties during heating and melting. It is a component that can be realized and cured to give a flexible cured product at room temperature to high temperature. Such component (B) preferably has an average particle size in the range of 0.01 to 1.0 μm, more preferably in the range of 0.01 to 0.75 μm. If the average particle size of component (B) is less than the above lower limit, the melt viscosity of the composition may not sufficiently decrease even in the presence of component (C0). Further, when the average particle size of the component (B) exceeds the above upper limit, even when the component (C0) is heated and melted at a high temperature, the component (C0 ) component may migrate, and adhesion may not be sufficiently improved.

In particular, from the standpoint of improving the flexibility of the cured product at high temperatures, the component (B) is an inorganic filler substantially free of coarse particles having an average particle size of 5 μm or more, and in particular the particulate component (A0). By using an inorganic filler with a particle size smaller than that of component (A0), it is possible to provide a curable granular silicone composition that cures to give a flexible cured product at room temperature to high temperature. In addition, when an inorganic filler containing coarse particles having an average particle diameter of 5 μm or more is used as the component (B), when the component (C0) is heated and melted at a high temperature, it melts in the outer phase of the fluid formed by hot melt ( The C0) component may migrate, resulting in insufficient adhesion.

Furthermore, the curable granular silicone composition of the present invention has a high light reflectance in the visible light region, and the component (B) is typically titanium oxide fine particles having an average particle size of 0.5 µm or less. It is preferable that the main component is a white pigment that does not substantially contain coarse particles having an average particle size of 5 μm or more. Here, "not substantially containing coarse particles having an average particle diameter of 5 µm or more" means that when component (B) is observed with an electron microscope or the like, coarse particles having an average particle diameter of 5 µm or more are not observed in the major diameter of the particles, It means that the volume ratio of coarse particles having an average particle size of 5 μm or more is less than 1% when the particle size distribution of component (B) is measured by laser diffraction scattering particle size distribution measurement or the like.

Such a component (B) is preferably at least one filler that does not have a softening point or does not soften below the softening point of the component (A), thereby improving the handling workability of the present composition. However, it may be a component that imparts mechanical properties and other properties to the cured product of the present composition. Component (B) is exemplified by inorganic fillers, organic fillers, and mixtures thereof, with inorganic fillers being preferred. Examples of inorganic fillers include reinforcing fillers, white pigments, thermally conductive fillers, conductive fillers, phosphors, and mixtures of at least two of these. It is preferable to use a white pigment as a main component. Examples of organic fillers include silicone resin-based fillers, fluororesin-based fillers, and polybutadiene resin-based fillers. The shape of these fillers is not particularly limited, and may be spherical, spindle-shaped, flattened, needle-shaped, amorphous, or the like.

The curable granular silicone composition of the present invention has a high light reflectance in the visible light region and provides a cured product that is useful as a light reflecting material, particularly for use in optical semiconductors (LEDs). It is preferable that the main component of component (B) is a white pigment that does not substantially contain coarse particles having an average particle size of 5 μm or more, because it imparts whiteness to the cured product and improves light reflectivity. Examples of white pigments include metal oxides such as titanium oxide, aluminum oxide, zinc oxide, zirconium oxide, and magnesium oxide; hollow fillers such as glass balloons and glass beads; and barium sulfate, zinc sulfate, barium titanate, and aluminum nitride. , boron nitride, and antimony oxide. Titanium oxide is preferred because of its high light reflectance and hiding properties. Aluminum oxide, zinc oxide, and barium titanate are preferred because of their high light reflectance in the UV region. Also, the white pigment may be surface-treated with a silane coupling agent, silica, aluminum oxide, or the like.

Component (B) used in the curable granular silicone composition of the present invention is particularly preferably (B1) fine titanium oxide particles having an average particle size in the range of 0.10 to 0.75 μm. High filling gives the cured product high light reflectance and hiding power in the visible wavelength region, and the light reflectance in the visible wavelength region hardly changes when comparing the low wavelength side and the high wavelength side. In addition, by using titanium oxide fine particles having an average particle size within the above range, when the component (C0) described later melts at a high temperature, it melts into the external phase of the fluid formed by hot-melting (C0). There is an advantage that the components are less likely to migrate, and the hot-melt flowability of the entire composition is sufficiently improved without impairing the adhesiveness (adhesive strength) during curing.

Component (B) is preferably 90% by mass or more, more preferably 95% by mass or more, of (B1) titanium oxide fine particles having an average particle size in the range of 0.10 to 0.75 μm. Further, the component (B) may be a mixture of the titanium oxide fine particles as the component (B1) and a reinforcing filler to be described later. A mixture of 0.01 to 0.10 μm fumed silica is particularly preferred from the standpoint of mechanical strength of the cured product.

As described above, the component (B) is an inorganic filler having an average particle size of 1.0 μm or less, and is mainly composed of a white pigment (such as the above titanium oxide fine particles) that does not substantially contain coarse particles having an average particle size of 5 μm or more. Although it is preferable to use it as a component, when using this composition for applications such as sealants, protective agents, adhesives, etc., it is necessary to impart mechanical strength to the cured product and improve protective properties or adhesiveness. Therefore, a reinforcing filler may be blended as the component (B). Examples of reinforcing fillers include fumed silica, precipitated silica, fused silica, calcined silica, fumed titanium dioxide, quartz, calcium carbonate, diatomaceous earth, aluminum oxide, aluminum hydroxide, zinc oxide, and zinc carbonate. . Organoalkoxysilanes such as methyltrimethoxysilane; organohalosilanes such as trimethylchlorosilane; organosilazanes such as hexamethyldisilazane; The surface may be treated with a siloxane oligomer such as a -silanol group-blocked methylphenylsiloxane oligomer or an α,ω-silanol group-blocked methylvinylsiloxane oligomer. This reinforcing filler substantially does not contain coarse particles having an average particle size of 5 μm or more. Further, fibrous fillers such as calcium metasilicate, potassium titanate, magnesium sulfate, sepiolite, xonolite, aluminum borate, rock wool, and glass fiber may be used as reinforcing fillers.

As long as component (B) is an inorganic filler with an average particle size of 1.0 μm or less, it may contain fine silicone particles that do not correspond to component (A), and the stress relaxation properties can be improved or adjusted as desired. can. Examples of silicone fine particles include non-reactive silicone resin fine particles and silicone elastomer fine particles. From the standpoint of improving flexibility or stress relaxation properties, silicone elastomer fine particles are preferred.

Silicone elastomer fine particles are crosslinked products of linear diorganopolysiloxane mainly composed of diorganosiloxy units (D units). Silicone elastomer microparticles can be prepared by crosslinking reaction of diorganopolysiloxane by hydrosilylation reaction, condensation reaction of silanol group or the like. A diorganopolysiloxane having an unsaturated hydrocarbon group such as an alkenyl group at its chain or end can be suitably obtained by cross-linking reaction in the presence of a hydrosilylation reaction catalyst. The fine particles of silicone elastomer can have various shapes such as spherical, flattened, and irregular shapes. Examples of commercial products of such silicone elastomer fine particles include "Torayfil E Series" and "EP Powder Series" manufactured by Dow Corning Toray Co., Ltd., and "KMP Series" manufactured by Shin-Etsu Chemical Co., Ltd., and the like.
The silicone elastomer fine particles may be surface-treated. Examples of surface treatment agents include methylhydrogenpolysiloxane, silicone resins, metal soaps, silane coupling agents, silica, inorganic oxides such as titanium oxide, perfluoroalkylsilanes, and perfluoroalkyl phosphate salts. and fluorine compounds such as

When the present composition is used as a wavelength conversion material for an LED, a phosphor may be blended as the component (B) in order to convert the emission wavelength from the optical semiconductor element. The phosphor is not particularly limited as long as it has an average particle size of 1.0 μm or less. Yellow-, red-, green-, and blue-emitting phosphors composed of phosphors, sulfide phosphors, oxysulfide phosphors, and the like are exemplified. Examples of oxide-based phosphors include yttrium-, aluminum-, and garnet-based YAG-based green to yellow-emitting phosphors containing cerium ions; terbium-, aluminum-, and garnet-based TAG-based yellow-emitting phosphors containing cerium ions; Silicate-based green-to-yellow emitting phosphors containing europium ions are exemplified. Examples of oxynitride-based phosphors include silicon-, aluminum-, oxygen-, and nitrogen-based sialon-based red to green-emitting phosphors containing europium ions. Nitride-based phosphors include calcium-, strontium-, aluminum-, silicon-, and nitrogen-based cousin-based red-emitting phosphors containing europium ions. Examples of sulfide-based phosphors include ZnS-based green-emitting phosphors containing copper ions and aluminum ions. Examples of oxysulfide-based phosphors include Y ₂ O ₂ S-based red-emitting phosphors containing europium ions. In the present composition, two or more of these phosphors may be used in combination.

Furthermore, the present composition may contain a thermally conductive filler or an electrically conductive filler in order to impart thermal conductivity or electrical conductivity to the cured product. As the thermally conductive filler or conductive filler, as long as the average particle size is 1.0 μm or less, metal fine powder such as gold, silver, nickel, copper and aluminum; Fine powders in which metals such as gold, silver, nickel, and copper are vapor-deposited or plated on the powder surface; metal compounds such as aluminum oxide, magnesium oxide, aluminum nitride, boron nitride, and zinc oxide; graphite, and mixtures of two or more of these are exemplified. When electrical insulation is required for the present composition, metal oxide powders or metal nitride powders are preferred, and aluminum oxide powders, zinc oxide powders, or aluminum nitride powders are particularly preferred.

The content of component (B) is not limited, but within the range of 10 to 2000 parts by mass, within the range of 10 to 1500 parts by mass, or within the range of 10 to 1000 parts by mass per 100 parts by mass of component (A) can be compounded. In particular, the component (B) of the present invention does not substantially contain coarse particles having an average particle size of 5 μm or more, and even if it is blended in a relatively large amount with respect to the component (A), the composition can be handled easily and hot. 50 to 900 parts by mass per 100 parts by mass of component (A), since the gap-filling property during melting is not lowered, and the resulting cured product has excellent flexibility and mechanical strength at room temperature to high temperature, Blending in the ranges of 100 to 800 parts by weight and 150 to 750 parts by weight is preferred. Furthermore, in the composition of the present invention, 50% by mass or more, 60% by mass or more, or 70% by mass or more of the entire composition may be the above component (B), and in particular, the component (B1) may be the light reflectance is particularly preferred from the viewpoint of

[(C0) component: hot melt component]
Component (C0) is a characteristic hot-melt component of the present invention. exhibit higher liquidity than Therefore, the component corresponding to the (A0) component is not included in the (C0) component, and the kinematic viscosity (Vis A ) when the component (A0) melts at 150 ° C. and the kinematic viscosity (Vis _A ) when the component (C0) melts at 150 ° C. It is a feature of the present invention that Vis _A >Vis _C with respect to viscosity (Vis _C ). The means for measuring the kinematic viscosity is the same as described above for component (A0).

The type of component (C0) is not particularly limited as long as it satisfies the above conditions of kinematic viscosity when melted at 150° C., and is selected from various hot-melt synthetic resins, waxes, fatty acid metal salts, and the like. One or more types can be used. From the standpoint of hot-melt fluidity and gap-filling properties of the composition, when Vis _A is 10 to 2,000 Pa s, the kinematic viscosity (Vis _C ) of the component (C0) when melted is 1 of Vis _A. /5 or less is particularly preferable, and it is preferably in the range of 0.01 to 500 Pa·s, 0.01 to 300 Pa·s, and 0.01 to 200 Pa·s.

The component (C0) exhibits a kinematic viscosity lower than that of the component (A0) at a high temperature (150° C.) and forms a melt with excellent fluidity. Furthermore, by setting the component (B) within the scope of the present invention, the component (C0) in the melt made of the present composition quickly spreads throughout the composition at high temperatures, so that the melted composition is applied. In addition to lowering the viscosity of the base material surface and the composition as a whole, the surface friction of the base material and the molten composition is rapidly reduced, and the fluidity of the composition as a whole is greatly increased. Therefore, by adding a very small amount to the total amount of component (A0), the viscosity and fluidity of the molten composition can be increased without impairing the physical properties and adhesive strength of the cured silicone product derived from component (A0). can be improved.

The component (C0) may be a petroleum wax such as paraffin as long as it satisfies the above conditions of kinematic viscosity when melted. A hot-melt component is preferred, and metal salts of higher fatty acids such as stearic acid, palmitic acid, oleic acid and isononanoic acid are particularly preferred. Here, the type of the fatty acid metal salt is not particularly limited, but alkali metal salts such as lithium, sodium and potassium; alkaline earth metal salts such as magnesium, calcium and barium; and zinc salts are preferred. exemplified. These higher fatty acid metal salts can be obtained by a known method such as a melt-kneading method.

Component (C0) is particularly preferably (C1) a fatty acid metal salt with a free fatty acid content of 5.0% or less, 4.0% or less, and 0.05 to 3.5%. is more preferred. Examples of such a (C0) component include at least one metal stearate. From the standpoint of the technical effects of the present invention, the component (C0) preferably consists essentially of one or more metal stearates, such as calcium stearate (melting point 150°C) and zinc stearate (melting point 120°C). , and magnesium stearate (melting point 130° C.).

The amount of component (C0) used is such that the content of component (C0) is in the range of 0.01 to 5.0 parts by mass when the sum of components (A0) and (B) is 100 parts by mass, It may be 0.01 to 3.5 parts by mass, 0.01 to 3.0 parts by mass. If the amount of component (C0) used exceeds the above upper limit, the amount of component (C0) used will be excessive, and the adhesiveness and mechanical strength of the cured product of the curable silicone composition of the present invention will be insufficient. may become. If the amount of component (C0) used is less than the above lower limit, sufficient fluidity and gap-filling properties during heating and melting may not be achieved.

[(D) component: curing agent]
The component (D) is not limited as long as it can cure the component (A0). When component (A0) has an alkenyl group, component (D) is an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in one molecule and a hydrosilylation reaction catalyst, and (A0 ) component contains an alkenyl group and contains a catalyst for hydrosilylation reaction, component (D) may be only an organopolysiloxane having at least two silicon-bonded hydrogen atoms in one molecule, A hydrosilylation reaction catalyst may be used in combination. Further, when the component (A0) has an alkenyl group, the component (D) may be an organic peroxide, or may be used in combination with an organopolysiloxane having at least two silicon-bonded hydrogen atoms per molecule. good. On the other hand, when the component (A0) has silicon-bonded hydrogen atoms, the component (D) is an organopolysiloxane having at least two alkenyl groups in one molecule and a hydrosilylation reaction catalyst, and (A0 ) component has silicon-bonded hydrogen atoms and contains a catalyst for hydrosilylation reaction, component (D) may be only an organopolysiloxane having at least two alkenyl groups in one molecule, A hydrosilylation reaction catalyst may be used in combination. The timing of adding the component (D) is arbitrary, and when the component (A0) is synthesized in situ as a blend in the presence of the component (B) or the component (C), at the time of synthesizing the component (A0) may already be added to the system.

The organopolysiloxane in component (D) is an alkenyl group-containing organopolysiloxane represented by (a ₁ ) and/or (a ₂ ) above, or (a ₃ ) and/or (a ₄ ) above. Silicon-bonded hydrogen atom-containing organopolysiloxane represented by is exemplified.

When an organopolysiloxane is used as component (D), its content is not limited, but in order for the composition to cure, the amount of silicon-bonded hydrogen atoms per 1 mol of alkenyl groups in the composition should be 0. Preferably, the amount is in the range of 0.5 to 20 moles, alternatively in the range of 1.0 to 10 moles.

Examples of hydrosilylation reaction catalysts include platinum-based catalysts, rhodium-based catalysts, and palladium-based catalysts. Platinum-based catalysts are preferred because they can significantly accelerate the curing of the present composition. Examples of platinum-based catalysts include platinum fine powder, chloroplatinic acid, chloroplatinic acid alcohol solutions, platinum-alkenylsiloxane complexes, platinum-olefin complexes, platinum-carbonyl complexes, and these platinum-based catalysts, silicone resins, polycarbonates. Catalysts dispersed or encapsulated in thermoplastic resins such as resins and acrylic resins are exemplified, and platinum-alkenylsiloxane complexes are particularly preferred. Examples of the alkenylsiloxane include 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, Alkenylsiloxanes in which some of the methyl groups of these alkenylsiloxanes are substituted with ethyl groups, phenyl groups or the like, and alkenylsiloxanes in which the vinyl groups of these alkenylsiloxanes are substituted with allyl groups, hexenyl groups or the like are exemplified. In particular, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane is preferable because the stability of this platinum-alkenylsiloxane complex is good. In addition, from the viewpoint of improving workability in handling and pot life of the composition, a particulate platinum-containing hydrosilylation reaction catalyst dispersed or encapsulated in a thermoplastic resin may be used. As a catalyst for accelerating the hydrosilylation reaction, non-platinum metal catalysts such as iron, ruthenium, and iron/cobalt may be used.

The amount of the hydrosilylation reaction catalyst to be added is such that the amount of metal atoms in mass units is within the range of 0.01 to 500 ppm, 0.01 to 100 ppm, or The amount is preferably within the range of 0.01 to 50 ppm.

Examples of organic peroxides include alkyl peroxides, diacyl peroxides, ester peroxides, and carbonate peroxides.

Examples of alkyl peroxides include dicumyl peroxide, di-tert-butyl peroxide, di-tert-butyl cumyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, 2 ,5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3, tert-butylcumyl, 1,3-bis(tert-butylperoxyisopropyl)benzene, 3,6,9-triethyl-3, 6,9-trimethyl-1,4,7-triperoxonane is exemplified.

Examples of diacyl peroxides include benzoyl peroxide, lauroyl peroxide, and decanoyl peroxide.

Examples of peroxide esters include 1,1,3,3-tetramethyl butyl peroxy neodecanoate, α-cumyl peroxy neo decanoate, tert-butyl peroxy neo decanoate, tert-butyl peroxy neoheptanoate, tert-butyl peroxypivalate, tert-hexyl peroxypivalate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, tert-amylperoxyl-2- Ethylhexanoate, tert-butylperoxy-2-ethylhexanoate, tert-butylperoxyisobutyrate, di-tert-butylperoxyhexahydroterephthalate, tert-amylperoxy-3,5,5- Examples include trimethylhexanoate, tert-butylperoxy-3,5,5-trimethylhexanoate, tert-butylperoxyacetate, tert-butylperoxybenzoate and di-butylperoxytrimethyladipate.

Peroxycarbonates include di-3-methoxybutylperoxydicarbonate, di(2-ethylhexyl)peroxydicarbonate, diisopropylperoxycarbonate, tert-butylperoxyisopropylcarbonate, di(4-tert-butylcyclohexyl ) peroxydicarbonate, dicetyl peroxydicarbonate, dimyristyl peroxydicarbonate.

Preferably, the organic peroxide has a half-life of 10 hours at a temperature of 90°C or higher, or 95°C or higher. Examples of such organic peroxides include dicumyl peroxide, di-t-butyl peroxide, di-t-hexyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di( tert-butylperoxy)hexane, 1,3-bis(tert-butylperoxyisopropyl)benzene, di-(2-t-butylperoxyisopropyl)benzene, 3,6,9-triethyl-3,6,9- Trimethyl-1,4,7-triperoxonane is exemplified.

The content of the organic peroxide is not limited, but it should be in the range of 0.05 to 10 parts by weight, or in the range of 0.10 to 5.0 parts by weight, per 100 parts by weight of component (A0). is preferred.

In addition, the composition may contain a curing retarder and an adhesion imparting agent as other optional components as long as they do not impair the object of the present invention.

Curing retarders include 2-methyl-3-butyn-2-ol, 3,5-dimethyl-1-hexyn-3-ol, 2-phenyl-3-butyn-2-ol, 1-ethynyl-1- alkyne alcohols such as cyclohexanol; enyne compounds such as 3-methyl-3-penten-1-yne and 3,5-dimethyl-3-hexene-1-yne; tetramethyltetravinylcyclotetrasiloxane, tetramethyltetrahexenylcyclo alkenyl group-containing low molecular weight siloxanes such as tetrasiloxane; and alkynyloxysilanes such as methyl-tris(1,1-dimethylpropynyloxy)silane and vinyl-tris(1,1-dimethylpropynyloxy)silane. Although the content of this curing retardant is not limited, it is preferably in the range of 10 to 10,000 ppm by mass based on the composition.

As the tackifier, an organosilicon compound having at least one silicon-bonded alkoxy group per molecule is preferred. Examples of the alkoxy group include methoxy, ethoxy, propoxy, butoxy, and methoxyethoxy groups, with methoxy groups being particularly preferred. In addition, as the silicon-bonded group other than the alkoxy group in the organosilicon compound, a halogen-substituted or unsubstituted monovalent hydrocarbon group such as an alkyl group, an alkenyl group, an aryl group, an aralkyl group, or a halogenated alkyl group; glycidoxyalkyl groups such as 3-glycidoxypropyl group and 4-glycidoxybutyl group; 2-(3,4-epoxycyclohexyl)ethyl group and 3-(3,4-epoxycyclohexyl)propyl group; Examples include epoxycyclohexylalkyl groups; epoxyalkyl groups such as 3,4-epoxybutyl group and 7,8-epoxyoctyl group; acrylic group-containing monovalent organic groups such as 3-methacryloxypropyl group; and hydrogen atoms. The organosilicon compound preferably has a group capable of reacting with an alkenyl group or a silicon-bonded hydrogen atom in the composition, and specifically preferably has a silicon-bonded hydrogen atom or an alkenyl group. Moreover, the organosilicon compound preferably has at least one epoxy group-containing monovalent organic group in one molecule because it can impart good adhesiveness to various substrates. Examples of such organosilicon compounds include organosilane compounds, organosiloxane oligomers, and alkylsilicates. The molecular structure of the organosiloxane oligomer or alkylsilicate may be linear, partially branched linear, branched, cyclic, or network. Preferably. Examples of organosilicon compounds include silane compounds such as 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 3-methacryloxypropyltrimethoxysilane; a silicon atom in one molecule. A siloxane compound having at least one bonded alkenyl group or silicon-bonded hydrogen atom and at least one silicon-bonded alkoxy group, a silane compound or siloxane compound having at least one silicon-bonded alkoxy group and a silicon-bonded hydroxy group in one molecule Examples include mixtures of radicals and siloxane compounds each having at least one silicon-bonded alkenyl group, methylpolysilicate, ethylpolysilicate, and epoxy group-containing ethylpolysilicate. This tackifier is preferably a low-viscosity liquid, and although its viscosity is not limited, it is preferably in the range of 1 to 500 mPa·s at 25°C. Although the content of the adhesion promoter is not limited, it is preferably in the range of 0.01 to 10 parts by weight per 100 parts by weight of the composition.

Furthermore, the present composition may contain, as other optional components, at least one liquid organopolysiloxane of the above (a1) to the above (a4); iron oxide (red iron oxide), cerium oxide , cerium dimethylsilanolate, fatty acid cerium salts, cerium hydroxide, and zirconium compounds;

The above composition is an inorganic filler having an average particle size of 1.0 μm or less, preferably the component (B) substantially free of coarse particles having an average particle size of 5 μm or more, and the component (A0). When used in combination with a certain hot-melt silicone, the cured product is flexible at room temperature to high temperatures, specifically 25°C to 150°C, has excellent stress relaxation properties, and deforms such as bending at room temperature. It also has the excellent property of being hard to break. Furthermore, as the above component (B), by blending a large amount of a white pigment that does not contain coarse particles typified by titanium oxide fine particles having an average particle size in the range of 0.10 to 0.75 μm, It realizes a high light reflectance in a thin film, especially a high light reflectance in a thin film.

In addition, since the above composition contains a component (C0) that improves the fluidity of the hot melt composition at high temperatures, it was optimized to give a cured product with excellent flexibility, toughness and adhesion. While using a hot-melt silicone, the melt viscosity of the composition can be greatly reduced, and sufficient fluidity and gap-filling properties can be achieved during heating and melting.

A cured product obtained by curing the above composition has a storage modulus (G') value at 25°C of 2000 MPa or less and a storage modulus (G') value at 150°C of 100 MPa or less. can be designed and is preferable.

The above composition cures to give a cured product having a high spectral reflectance in the visible light region. may be designed to give a cured product of 95% or more, more preferably 97% or more. Furthermore, the cured product may be designed to have a spectral reflectance of 90% or more, preferably 95% or more, more preferably 97% or more at a wavelength of 700 nm in a thickness of 100 μm.

In particular, the above composition is a component (B) that does not substantially contain coarse particles with an average particle size of 5 μm or more, and uses an inorganic filler that gives a high light reflectance, so that the light reflectance in the visible light region has a characteristic that the wavelength dependence of is extremely small. That is, the above composition, when cured, has a light reflectance (ρ ₄₅₀ ) at a wavelength of 450 nm and a light reflectance (ρ ₇₀₀ ) at a wavelength of 700 nm at a thickness of 100 μm, both of which are 90% or more, and
To give a cured product in which the difference in light reflectance represented by (ρ ₇₀₀ /ρ ₄₅₀ ) x 100 (%) is less than 10%, preferably less than 5%, more preferably less than 3%, can be designed.

The composition may be in the form of pellets or sheets. Pellets of the present composition are obtained by tableting the present composition, and are excellent in handling workability and curability. In addition, a "pellet" may also be called a "tablet." Although the shape of the pellet is not limited, it is usually spherical, ellipsoidal, or cylindrical. Also, the size of the pellet is not limited, but for example, it has an average particle size or circle equivalent diameter of 500 μm or more. The present composition may also be used in the form of a paste by heating and melting the entire composition.

The composition may be molded into a sheet for use. For example, a sheet made of a curable granular silicone composition having an average thickness of 500 µm or more, preferably several millimeters, has hot-melt properties and heat-curing properties at high temperatures. It is advantageous in terms of excellent handling workability and melting properties.

Preferably, the composition is non-flowing at 25°C. Here, non-flowing means that it does not deform or flow in a no-load state. Preferably, it does not deform or flow at 25° C. and in a no-load state when molded into pellets, tablets, or the like. is. Such non-flowability can be evaluated, for example, by placing the molded composition on a hot plate at 25° C. and not substantially deforming or flowing even when no load or a constant load is applied. This is because, if it is non-flowing at 25° C., the shape retention at that temperature is good and the surface tackiness is low.

The softening point of this composition is preferably 100° C. or lower. Such a softening point is determined by pressing a load of 100 grams on a hot plate from above for 10 seconds, removing the load, and then measuring the amount of deformation of the composition. means the temperature at which

Since the present composition tends to undergo a rapid decrease in viscosity under high temperature and high pressure (that is, during the molding process), it is preferable to use values measured under similar high temperature and high pressure as useful melt viscosity values. Therefore, it is preferable to measure the melt viscosity of the present composition under high pressure using a Koka flow tester (manufactured by Shimadzu Corporation) rather than using a rotational viscometer such as a rheometer. Specifically, the melt viscosity at 150° C. is preferably 150 Pa·s or less, more preferably 100 or less. This is because the adhesiveness to the substrate is good after cooling to 25° C. after hot-melting the composition.

The cure properties of the composition can be engineered as desired and evaluated using a rheometer. The curing characteristics of the present composition are defined by T ₁ , the time (seconds) for obtaining a 1% torque value and a 90% torque value when the torque value after 3 minutes at a constant temperature of 150 to 180° C. is defined as 100, It can be evaluated based on the value of _T90 . The present composition preferably has _a T1 of 20 seconds or more, alternatively 25 seconds or more when measured at a constant temperature of 150 to 180°C. Further, it is preferable that the _T90 measured at 150 to 180° C. is 145 seconds or less, or 140 seconds or less. A rheometer MDR2000 (manufactured by Alpha Technologies) is exemplified as a rheometer used for the measurement.

[Method for producing curable hot-melt silicone composition]
The present composition is produced by powder-mixing component (A0), component (B), component (C0), component (D), and other components at a temperature below the softening point of component (A0). be able to. The powder mixer used in this production method is not limited, and includes single- or double-screw continuous mixers, double rolls, Ross mixers, Hobart mixers, dental mixers, planetary mixers, kneader mixers, lab millers, small pulverizers, and Henschel mixers. are exemplified, preferably a labo miller, a small pulverizer, and a Henschel mixer.
Further, when the (A0) component is synthesized in situ in the presence of the (B) component, the (C0) component and the (D) component, once a paste-like composition is prepared by a known method, it is heated as desired. It may be produced by semi-curing so that the component (D) remains.

[Molding method of cured product]
The composition can be cured by a method comprising at least the following steps (I) to (III).
(I) a step of heating the present composition to a softening point or higher of component (A0) to melt;
(II) A step of injecting the curable silicone composition obtained in step (I) into a mold, or a step of spreading the curable silicone composition obtained in step (I) over the mold by clamping the mold. and (III) curing the curable silicone composition injected in step (II).

In the above process, a transfer molding machine, a compression molding machine, an injection molding machine, an auxiliary ram molding machine, a slide molding machine, a double ram molding machine, or a low pressure encapsulation molding machine can be used. In particular, the composition of the present invention can be suitably used for the purpose of obtaining cured products by transfer molding and compression molding.

Finally, in step (III), the curable silicone composition injected (applied) in step (II) is cured. In addition, when an organic peroxide is used as the component (D), the heating temperature is preferably 150° C. or higher, or 170° C. or higher.

The type D durometer hardness at 25°C of the cured product obtained by curing the present composition is preferably 40 or more, or preferably 50 or more, because it is suitable as a protective member for semiconductors and the like. The type D durometer hardness is determined by a type D durometer according to JIS K 6253-1997 "Testing method for hardness of vulcanized rubber and thermoplastic rubber".

[Use of composition]
The present composition has hot-melt properties and is excellent in handling workability and curability. agents; sealants and light reflectors for optical semiconductors such as light-emitting diodes, photodiodes, phototransistors and laser diodes; adhesives, potting agents, protective agents and coating agents for electrical and electronic applications. Moreover, since the present composition has hot-melt properties, it is also suitable as a material for transfer molding, compression molding, or injection molding. In particular, a sheet obtained by molding the composition of the present invention is useful as a material for compression molding.

[Usage of cured product]
The use of the cured product of the present invention is not particularly limited, but the composition of the present invention has hot melt properties, excellent moldability and gap fill properties, and the cured product has the above flexibility at room temperature, It has high stress relaxation properties, bending strength and can be designed to have high light reflectance. Therefore, the cured product obtained by curing the present composition can be suitably used as a light reflecting material, particularly as a light reflecting material for optical semiconductor devices.

Although the optical semiconductor device provided with the light reflecting material made of the cured product of the present invention is not particularly limited, it is preferably a chip-scale package type optical semiconductor device in which the wall thickness of the light reflecting material is thin.

The hot-melt curable silicone composition of the present invention and the method for producing the same will be described in detail with reference to examples and comparative examples. In the formula, Me, Ph and Vi represent a methyl group, a phenyl group and a vinyl group, respectively. The softening point, melt viscosity, moldability, and adhesive strength of the curable silicone compositions of each example and comparative example were measured as follows, and are shown in Table 1.

[Softening point of hot-melt silicone]
The hot-melt silicone was placed on a hot plate set at 25° C. to 100° C., and the softening point was defined as the temperature at which the silicone was liquefied while checking the condition with a spatula.
[Melt Viscosity of Hot Melt Raw Material]
The melt viscosities of the hot-melt silicone raw material and the metal stearate at 150°C were measured using a rotational viscometer: rheometer AR2000EX (manufactured by TA Instruments Japan Co., Ltd.) at a shear rate of 5 (1/s). ).

[Softening point of curable hot melt silicone composition]
A curable hot-melt silicone composition was molded into cylindrical pellets of φ14 mm×22 mm. The pellet was placed on a hot plate set at 25° C. to 100° C., and a load of 100 g weight was continuously pressed from above for 10 seconds. After the load was removed, the amount of deformation of the pellet was measured. The softening point was defined as the temperature at which the amount of deformation in the height direction became 1 mm or more.

[Melt Viscosity of Curable Hot Melt Silicone Composition]
The melt viscosity of the curable hot-melt silicone composition at 150° C. was measured using a Koka Flow Tester CFT-500EX (manufactured by Shimadzu Corporation) under a pressure of 100 kgf using a nozzle with a diameter of 0.5 mm.

[Moldability]
The curable granular silicone composition was integrally molded with a copper lead frame using a transfer molding machine to produce a molding of 35 mm long×25 mm wide×1 mm high. As for the molding conditions, in Examples 1 to 5, Example 7 and Comparative Examples 1 to 4, the mold temperature was 150° C. and the mold clamping time was 120 seconds. After the molded product was removed from the mold and cooled to 25° C., the presence of cracks and molding defects such as peeling from the lead frame was visually checked.
[Adhesion strength]
About 100 mg of a curable hot-melt silicone composition was placed on an aluminum plate of 25 mm x 75 mm at 5 locations using tweezers, and the composition was covered with a 6 mm square aluminum chip with a thickness of 1 mm and heated at 150°C. It was crimped with a 1 kg plate. This was then heated at 150° C. for 2 hours to cure the curable hot melt silicone composition. After cooling to room temperature, the die shear strength was measured using a shear strength measuring device (Bond Tester SS-100KP manufactured by Seishin Shoji Co., Ltd.).

[Reference example 1]
A white solid at 25° C. in a 1 L flask with the average unit formula:
( _PhSiO3 /2) _0.80 (Me2ViSiO1 _{/2 ) 0.20}
55% by mass of resinous organopolysiloxane represented by - 270.5 g of toluene solution, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
21.3 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane at both ends of the molecular chain with a viscosity of 5 mPa s (content of silicon-bonded hydrogen atoms = 0.6% by mass) represented by (in the resinous organopolysiloxane 0.5 mol of silicon-bonded hydrogen atoms in this component per 1 mol of vinyl group) and 1,3-divinyltetramethyldisiloxane of 1,3-divinyltetramethyldisiloxane complex of platinum 0.034 g of a solution (content of platinum metal = about 4000 ppm) (an amount of platinum metal of 10 ppm by mass with respect to the liquid mixture) was added and stirred uniformly at room temperature. Thereafter, the temperature in the flask was raised to 100° C. in an oil bath, and the mixture was stirred for 2 hours under reflux of toluene to obtain a resinous organosiloxane derived from the resinous organopolysiloxane and a chain organosiloxane derived from the diphenylsiloxane. A toluene solution of an organosiloxane crosslinked product (1) composed of siloxane and having a vinyl group that did not participate in the above reaction was prepared. When this organosiloxane crosslinked product (1) was analyzed by FT-IR, no silicon-bonded hydrogen atom peak was observed. The softening point of this organosiloxane crosslinked product (1) was 75°C, and its melt viscosity at 150°C was 100 Pa·s.

[Reference example 2]
Into a 500 mL 4-neck round-bottom flask equipped with a Dean-Stark apparatus connected to a thermometer, Teflon stirrer, and water-cooled condenser and prefilled with toluene, the average unit formula:
( _PhSiO3/2 ) _n
(In the formula, n is a positive number with which the weight average molecular weight of the present organopolysiloxane is 1,500.)
318.6 g of a 56.5% by weight toluene solution of organopolysiloxane represented by is charged under a nitrogen atmosphere. Heat at toluene reflux temperature for 30 minutes to remove 0.54 g of water. Next, it was cooled to 108° C., and 4.24 g (0.0187 mol) of a mixture of methyltriacetoxysilane/ethyltriacetoxysilane having a molar ratio of 1:1 and methylphenylpolysiloxane (silanol group-blocked at both ends of the molecular chain) ( 224.24 g of a methylphenylpolysiloxane mixture which had been reacted with 220 g (1.614 mol) of polymerisation degree=181) at room temperature for 1 hour was added. The reaction mixture was heated at toluene reflux temperature under nitrogen for 2 hours to remove an additional 2.01 g of water. After that, the reaction solution was cooled again to 108° C., 11.91 g (0.0633 mol) of vinylmethyldiacetoxysilane was added, and heated at toluene reflux temperature for another hour to remove 1.05 g of water. The reaction mixture was cooled to 90° C. and 47.8 g of deionized water was added, after which water was removed by azeotropic distillation. The reaction solution was cooled again to 108° C., 21.57 g (0.0949 mol) of a 1:1 molar mixture of methyltriacetoxysilane/ethyltriacetoxysilane was added, and after refluxing for 1 hour, the reaction mixture was Cooled to 90° C., added 47.8 g of deionized water, and refluxed to remove water by azeotropic distillation (this water addition and removal procedure was repeated twice). The same water treatment was repeated three times and finally 103.6 g of volatiles were removed by distillation at 118° C. to adjust the solids content of the reaction solution to about 70% by weight. The resulting product was found to be an organosiloxane block copolymer consisting of resinous organosiloxane blocks containing 2 mole percent vinyl groups and linear organosiloxane blocks. The softening point of this organosiloxane block copolymer (2) was 85°C, and its melt viscosity at 150°C was 570 Pa·s.

Next, 292 g of a solution of this organosiloxane block copolymer having a solid content concentration of 50% by mass was added to a 1,3-divinyltetramethyldisiloxane solution of a 1,3-divinyltetramethyldisiloxane complex of platinum (content of platinum metal = about 4000 ppm) 0.034 g (the amount of platinum metal is 10 ppm by mass with respect to the liquid mixture) is added and uniformly stirred at room temperature (25 ° C.) to obtain an organosiloxane block copolymer containing a platinum catalyst ( A toluene solution of 2) was prepared.

[Reference example 3]
A white solid at 25° C. in a 1 L flask with the average unit formula:
( _PhSiO3 /2) _0.80 (Me2ViSiO1 _{/2 ) 0.20}
270.5 g of a 55 mass% toluene solution of a resinous organopolysiloxane represented by and a 1,3-divinyltetramethyldisiloxane solution of a 1,3-divinyltetramethyldisiloxane complex of platinum (content of platinum metal = about 4000 ppm) was added and uniformly stirred at room temperature (25°C) to prepare a toluene solution of resinous organopolysiloxane (3) containing 10 ppm by mass of platinum metal. The resinous organopolysiloxane (3) had a softening point of 100°C and a viscosity of 30 Pa·s measured at 150°C with a rotational viscometer.

[Reference Example 4]
The toluene solution of the organosiloxane cross-linked product (1) prepared in Reference Example 1 was spray-dried at 40° C. while removing the toluene and micronized to prepare spherical hot-melt silicone microparticles (1). Observation of the fine particles with an optical microscope revealed that the particle diameter was 5 to 10 μm and the average particle diameter was 7.5 μm.

[Reference Example 5]
The toluene solution of the organosiloxane block copolymer (2) prepared in Reference Example 2 was spray-dried at 40° C. while removing the toluene and granulated to prepare spherical hot-melt silicone fine particles (2). Observation of the fine particles with an optical microscope revealed that the particle diameter was 5 to 10 μm and the average particle diameter was 6.5 μm.

[Reference example 6]
The toluene solution of the resinous organopolysiloxane (3) prepared in Reference Example 3 was spray-dried at 40° C. while removing the toluene and granulated to prepare spherical hot-melt silicone microparticles (3). Observation of the fine particles with an optical microscope revealed that the particle diameter was 5 to 10 μm and the average particle diameter was 7.9 μm.

[Example 1]
Hot-melt silicone microparticles (1) 89.3 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
10.7 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6% by mass) having a viscosity of 5 mPa s, {in silicone fine particles (1) 1.0 mol of silicon-bonded hydrogen atoms in the diphenylsiloxane with respect to 1 mol of vinyl groups], 1-ethynyl-1-cyclohexanol (an amount of 300 ppm by mass with respect to the present composition) ), 302.2 g of titanium oxide having an average particle size of 0.28 μm (CR-93 manufactured by Ishihara Sangyo Co., Ltd.), 1.3 g of fumed silica having an average particle size of 0.04 μm (AEROSIL 50 of Nippon Aerosil Co., Ltd.), and an average particle size of 0.8 g of 7.5 μm calcium stearate (manufactured by Kawamura Kasei Co., Ltd., melt viscosity at 150° C. is 5 Pa s) is put into a small pulverizer all at once and stirred at room temperature (25° C.) for 1 minute to give a uniform white color. of curable particulate silicone compositions were prepared. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Example 2]
Hot-melt silicone microparticles (1) 89.3 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
10.7 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6% by mass) having a viscosity of 5 mPa s, {in silicone fine particles (1) 1.0 mol of silicon-bonded hydrogen atoms in the diphenylsiloxane with respect to 1 mol of vinyl groups], 1-ethynyl-1-cyclohexanol (an amount of 300 ppm by mass with respect to the present composition) ), 302.2 g of titanium oxide having an average particle size of 0.28 μm (CR-93 manufactured by Ishihara Sangyo Co., Ltd.), 1.3 g of fumed silica having an average particle size of 0.04 μm (AEROSIL 50 of Nippon Aerosil Co., Ltd.), and an average particle size of 0.8 g of 7.5 μm zinc stearate (manufactured by Kawamura Kasei Co., Ltd., melt viscosity at 150° C. is 0.3 Pa s) was put into a small pulverizer and stirred for 1 minute at room temperature (25° C.). A uniform white curable particulate silicone composition was prepared. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Example 3]
Hot-melt silicone microparticles (1) 74.1 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
11.1 g of dimethylhydrogensiloxy group-blocked diphenylsiloxane at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6% by mass) with a viscosity of 5 mPa s and a viscosity of 1,000 mPa s. ,
Average formula _Me2ViSiO (MePhSiO) _{17.5 SiMe2Vi}
14.8 g of methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both ends of the molecular chain represented by (vinyl group content = 2.1% by mass)
{An amount that gives 1.0 mol of silicon-bonded hydrogen atoms in the diphenylsiloxane per 1 mol of vinyl groups in the silicone microparticles (1) and methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both molecular chain ends}, 1-ethynyl-1-cyclohexanol (300 ppm by mass with respect to the present composition), titanium oxide having an average particle size of 0.5 μm (SX-3103 manufactured by Sakai Chemical Industry Co., Ltd.) 297.6 g, average particle size 2.4 g of 0.04 μm fumed silica (AEROSIL 50 from Nippon Aerosil Co., Ltd.) and 1.6 g of calcium stearate with an average particle size of 7.5 μm (manufactured by Kawamura Kasei Co., Ltd., melt viscosity at 150° C. of 5 Pa s) were placed in a small container. The mixture was placed in a pulverizer and stirred at room temperature (25° C.) for 1 minute to prepare a uniform white curable granular silicone composition. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Example 4]
Hot-melt silicone microparticles (1) 74.1 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
11.1 g of dimethylhydrogensiloxy group-blocked diphenylsiloxane at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6% by mass) with a viscosity of 5 mPa s and a viscosity of 1,000 mPa s. ,
Average formula _Me2ViSiO (MePhSiO) _{17.5 SiMe2Vi}
14.8 g of methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both ends of the molecular chain represented by (vinyl group content = 2.1% by mass)
{An amount that gives 1.0 mol of silicon-bonded hydrogen atoms in the diphenylsiloxane per 1 mol of vinyl groups in the silicone microparticles (1) and methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both molecular chain ends}, 1-ethynyl-1-cyclohexanol (300 ppm by mass with respect to the present composition), titanium oxide having an average particle size of 0.5 μm (SX-3103 manufactured by Sakai Chemical Industry Co., Ltd.) 297.6 g, average particle size 2.4 g of 0.04 μm fumed silica (AEROSIL 50 from Nippon Aerosil Co., Ltd.) and zinc stearate having an average particle size of 7.5 μm (manufactured by Kawamura Kasei Co., melt viscosity at 150° C. is 0.3 Pa·s)1. 6 g of the mixture was put into a small pulverizer all at once and stirred at room temperature (25° C.) for 1 minute to prepare a uniform white curable granular silicone composition. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Example 5]
Hot-melt silicone microparticles (2) 90.9 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
4.5 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane having a viscosity of 5 mPa s at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6 mass%), average unit formula:
( _PhSiO3/2 ) _0.4 ( _{HMe2SiO1/ 2} ) _0.6
4. A branched-chain organopolysiloxane having a viscosity of 25 mPa·s and having two or more silicon-bonded hydrogen atoms in one molecule represented by (content of silicon-bonded hydrogen atoms=0.65% by mass); 5 g {an amount of 1.0 mol of silicon-bonded hydrogen atoms in the above diphenylsiloxane and organopolysiloxane per 1 mol of vinyl groups in silicone fine particles (2)}, oxidized to an average particle size of 0.28 µm 300.0 g of titanium (CR-93 manufactured by Ishihara Sangyo Co., Ltd.) and 1.6 g of zinc stearate with an average particle size of 7.5 μm (manufactured by Kawamura Kasei Co., Ltd., melt viscosity at 150 ° C. is 0.3 Pa s) were placed in a small size. The mixture was placed in a pulverizer and stirred at room temperature (25° C.) for 1 minute to prepare a uniform white curable granular silicone composition. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Example 6]
Hot-melt silicone microparticles (2) 86.2 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
5.2 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane having a viscosity of 5 mPa s at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6 mass%), average unit formula:
( _PhSiO3/2 ) _0.4 ( _{HMe2SiO1/ 2} ) _0.6
4. A branched-chain organopolysiloxane having a viscosity of 25 mPa·s and having two or more silicon-bonded hydrogen atoms in one molecule represented by (content of silicon-bonded hydrogen atoms=0.65% by mass); 3g
Viscosity is 1,000 mPa s,
Average formula _Me2ViSiO (MePhSiO) _{17.5 SiMe2Vi}
4.3 g of methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both ends of the molecular chain represented by (vinyl group content = 2.1% by mass)
{The number of silicon-bonded hydrogen atoms in the diphenylsiloxane and the organopolysiloxane is 1.0 mol per 1 mol of vinyl groups in the silicone fine particles (2) and dimethylvinylsiloxy group-blocked methylphenylpolysiloxane at both molecular chain ends. amount}, 297.4 g of titanium oxide having an average particle size of 0.5 μm (SX-3103 manufactured by Sakai Chemical Industry Co., Ltd.), and zinc stearate having an average particle size of 7.5 μm (manufactured by Kawamura Kasei Co., Ltd., melted at 150 ° C. 1.6 g (viscosity: 0.3 Pa·s) was put into a small pulverizer and stirred at room temperature (25° C.) for 1 minute to prepare a uniform white curable granular silicone composition. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Example 7]
Hot-melt silicone microparticles (3) 78.1 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
21.9 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane having a viscosity of 5 mPa s at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6% by mass), represented by
{The amount of silicon-bonded hydrogen atoms in the diphenylsiloxane becomes 1.0 moles per mole of vinyl groups in the silicone fine particles (3)} Titanium oxide with an average particle size of 0.5 µm (manufactured by Sakai Chemical Industry Co., Ltd.) SX-3103) 296.9 g, 4.3 g of fumed silica having an average particle size of 0.04 μm (AEROSIL 50 from Nippon Aerosil Co., Ltd.), and zinc stearate having an average particle size of 7.5 μm (Kawamura Kasei Co., Ltd., at 150 ° C. (melt viscosity: 0.3 Pa·s) was put into a small pulverizer all at once and stirred at room temperature (25°C) for 1 minute to prepare a uniform white curable granular silicone composition. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Example 8]
Average unit formula:
(MeViSiO2/2) _0.25 (Ph2SiO2 _{/ 2} ) _0.30 ( _PhSiO3 / ₂ ) _0.45 ( _HO1 /2) _0.02
68.2 g of methylvinylphenylpolysiloxane represented by
Viscosity is 1,000 mPa s,
Average formula _Me2ViSiO (MePhSiO) _{17.5 SiMe2Vi}
9.1 g of a methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both molecular chain ends represented by (vinyl group content = 2.1% by mass),
Formula: _HMe2SiO ( _Ph2SiO ) _SiMe2H
22.7 g (the above methylvinylphenylpolysiloxane and 1,3-divinyl-1,1,1,3-divinyl-1,1 of platinum, 3,3-tetramethyldisiloxane complex solution (an amount that makes platinum metal 5.0 ppm by mass with respect to this composition), 1-ethynyl-1-cyclohexanol (300 ppm by mass with respect to this composition) amount), 232.3 g of titanium oxide having an average primary particle size of 0.50.2 μm (SX-3103 manufactured by Sakai Chemical Industry Co., Ltd.), and zinc stearate having an average particle size of 7.5 μm (manufactured by Kawamura Kasei Co., Ltd., 150 ° C. The melt viscosity at 1.3 g was mixed to prepare a pasty curable silicone composition.

When this composition was heated at 120°C for 10 minutes, it became solid at 25°C and had hot-melt properties such that it became fluid when heated to 100°C or higher. When this composition was fluidized at 100° C. or higher and then heated at 150° C. for 10 minutes, it lost its hot-melt properties. This composition was injected into a Teflon (registered trademark) tube with a diameter of 14 mm and heated at 120° C. for 10 minutes to form cylindrical pellets with a height of 22 mm.

[Comparative Example 1]
Hot-melt silicone microparticles (1) 89.3 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
10.7 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6% by mass) having a viscosity of 5 mPa s, {in silicone fine particles (1) 1.0 mol of silicon-bonded hydrogen atoms in the diphenylsiloxane with respect to 1 mol of vinyl groups], 1-ethynyl-1-cyclohexanol (an amount of 300 ppm by mass with respect to the present composition) ), 302.2 g of titanium oxide having an average particle size of 0.28 μm (CR-93 manufactured by Ishihara Sangyo Co., Ltd.), and 1.3 g of fumed silica having an average particle size of 0.04 μm (AEROSIL 50 manufactured by Nippon Aerosil Co., Ltd.) were placed in a small pulverizer. and stirred at room temperature (25° C.) for 1 minute to prepare a uniform white curable granular silicone composition. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Comparative Example 2]
Hot-melt silicone microparticles (1) 74.1 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
11.1 g of dimethylhydrogensiloxy group-blocked diphenylsiloxane at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6% by mass) with a viscosity of 5 mPa s and a viscosity of 1,000 mPa s. ,
Average formula _Me2ViSiO (MePhSiO) _{17.5 SiMe2Vi}
14.8 g of methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both ends of the molecular chain represented by (vinyl group content = 2.1% by mass)
{An amount that gives 1.0 mol of silicon-bonded hydrogen atoms in the diphenylsiloxane per 1 mol of vinyl groups in the silicone microparticles (1) and methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both molecular chain ends}, 1-ethynyl-1-cyclohexanol (300 ppm by mass with respect to the present composition), 297.6 g of titanium oxide having an average particle size of 0.5 μm (SX-3103 manufactured by Sakai Chemical Industry Co., Ltd.), and average particles 2.4 g of fumed silica with a diameter of 0.04 μm (AEROSIL 50, manufactured by Nippon Aerosil Co., Ltd.) was put into a small pulverizer all at once and stirred at room temperature (25° C.) for 1 minute to produce a uniform white curable granular silicone composition. prepared. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Comparative Example 3]
Hot-melt silicone microparticles (2) 90.9 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
4.5 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane having a viscosity of 5 mPa s at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6 mass%), average unit formula:
( _PhSiO3/2 ) _0.4 ( _{HMe2SiO1/ 2} ) _0.6
4. A branched-chain organopolysiloxane having a viscosity of 25 mPa·s and having two or more silicon-bonded hydrogen atoms in one molecule represented by (content of silicon-bonded hydrogen atoms=0.65% by mass); 5g
{Amount of 1.0 mol of silicon-bonded hydrogen atoms in the diphenylsiloxane and the organopolysiloxane relative to 1 mol of vinyl groups in the silicone fine particles (2)}, and oxidation to an average particle diameter of 0.28 μm 300.0 g of titanium (CR-93 manufactured by Ishihara Sangyo Co., Ltd.) was put into a small pulverizer and stirred for 1 minute at room temperature (25° C.) to prepare a uniform white curable granular silicone composition. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Comparative Example 4]
Hot-melt silicone microparticles (2) 86.2 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
5.2 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane having a viscosity of 5 mPa s at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6 mass%), average unit formula:
( _PhSiO3/2 ) _0.4 ( _{HMe2SiO1/ 2} ) _0.6
4. A branched-chain organopolysiloxane having a viscosity of 25 mPa·s and having two or more silicon-bonded hydrogen atoms in one molecule represented by (content of silicon-bonded hydrogen atoms=0.65% by mass); 3g
Viscosity is 1,000 mPa s,
Average formula _Me2ViSiO (MePhSiO) _{17.5 SiMe2Vi}
4.3 g of methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both ends of the molecular chain represented by (vinyl group content = 2.1% by mass)
{The number of silicon-bonded hydrogen atoms in the diphenylsiloxane and the organopolysiloxane is 1.0 mol per 1 mol of vinyl groups in the silicone fine particles (2) and dimethylvinylsiloxy group-blocked methylphenylpolysiloxane at both molecular chain ends. and 297.4 g of titanium oxide having an average particle size of 0.5 μm (SX-3103 manufactured by Sakai Chemical Industry Co., Ltd.) are all put into a small pulverizer and stirred at room temperature (25 ° C.) for 1 minute to achieve uniformity. A white curable particulate silicone composition was prepared. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Comparative Example 5]
Hot-melt silicone microparticles (1) 89.3 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
10.7 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6% by mass) having a viscosity of 5 mPa s, {in silicone fine particles (1) 1.0 mol of silicon-bonded hydrogen atoms in the diphenylsiloxane with respect to 1 mol of vinyl groups], 1-ethynyl-1-cyclohexanol (an amount of 300 ppm by mass with respect to the present composition) ), spherical silica with an average particle size of 15 μm (HS-202 manufactured by Nippon Steel Materials Micron) 192.0 g, titanium oxide with an average particle size of 0.5 μm (SX-3103 manufactured by Sakai Chemical Industry) 156.3 g, fiber diameter = 6 μm, fiber length = 50 μm glass fiber (EFDE50-01 manufactured by Central Glass Co., Ltd.) 53.6 g, and calcium stearate with an average particle size of 7.5 μm (Kawamura Kasei Co., Ltd., melt viscosity at 150 ° C. is 5 Pa s ) was put into a small pulverizer all at once, and was all put into a small pulverizer and stirred at room temperature (25°C) for 1 minute to prepare a uniform white curable granular silicone composition. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Comparative Example 6]
Hot-melt silicone microparticles (1) 74.1 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
11.1 g of dimethylhydrogensiloxy group-blocked diphenylsiloxane at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6% by mass) with a viscosity of 5 mPa s and a viscosity of 1,000 mPa s. ,
Average formula _Me2ViSiO (MePhSiO) _{17.5 SiMe2Vi}
14.8 g of methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both ends of the molecular chain represented by (vinyl group content = 2.1% by mass)
{An amount that gives 1.0 mol of silicon-bonded hydrogen atoms in the diphenylsiloxane per 1 mol of vinyl groups in the silicone microparticles (1) and methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both molecular chain ends}, 1-ethynyl-1-cyclohexanol (300 ppm by mass with respect to the present composition), spherical silica with an average particle size of 15 μm (HS-202 manufactured by Nippon Steel Materials Micron) 192.0 g, average particle size 0.28 μm titanium oxide (CR-93 manufactured by Ishihara Sangyo Co., Ltd.) 156.3 g, fiber diameter = 6 μm, fiber length = 50 μm glass fiber (EFDE50-01 manufactured by Central Glass Co., Ltd.) 53.6 g, and average particle size 1.6 g of 7.5 μm zinc stearate (manufactured by Kawamura Kasei Co., Ltd., melt viscosity at 150° C. is 0.3 Pa s) was put into a small pulverizer all at once, and stirred for 1 minute at room temperature (25° C.). A uniform white curable particulate silicone composition was prepared. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Comparative Example 7]
Hot-melt silicone microparticles (2) 90.9 g, formula:
_HMe2SiO ( _Ph2SiO ) _SiMe2H
4.5 g of a dimethylhydrogensiloxy group-blocked diphenylsiloxane having a viscosity of 5 mPa s at both molecular chain ends (content of silicon-bonded hydrogen atoms = 0.6 mass%), average unit formula:
( _PhSiO3/2 ) _0.4 ( _{HMe2SiO1/ 2} ) _0.6
4. A branched-chain organopolysiloxane having a viscosity of 25 mPa·s and having two or more silicon-bonded hydrogen atoms in one molecule represented by (content of silicon-bonded hydrogen atoms=0.65% by mass); 5 g {the amount of silicon-bonded hydrogen atoms in the diphenylsiloxane and the organopolysiloxane being 1.0 mol per 1 mol of vinyl groups in the silicone fine particles (2)}, spherical silica having an average particle diameter of 15 μm ( Nippon Steel Materials Micron HS-202) 192.0 g, titanium oxide with an average particle size of 0.5 μm (SX-3103 manufactured by Sakai Chemical Industry) 156.3 g, fiber diameter = 6 μm, fiber length = 50 μm glass fiber 53.6 g of (EFDE50-01 manufactured by Central Glass Co., Ltd.) and 1.6 g of zinc stearate with an average particle size of 7.5 μm (manufactured by Kawamura Kasei Co., Ltd., melt viscosity at 150 ° C. is 0.3 Pa s) were finely ground. The mixture was placed in a machine and stirred at room temperature (25°C) for 1 minute to prepare a uniform white curable granular silicone composition. Next, this composition was tableted using a tableting machine to produce cylindrical pellets with a diameter of 14 mm and a height of 22 mm.

[Comparative Example 8]
Average unit formula:
(MeViSiO2/2) _0.25 (Ph2SiO2 _{/ 2} ) _0.30 ( _PhSiO3 / ₂ ) _0.45 ( _HO1 /2) _0.02
68.2 g of methylvinylphenylpolysiloxane represented by
Viscosity is 1,000 mPa s,
Average formula _Me2ViSiO (MePhSiO) _{17.5 SiMe2Vi}
9.1 g of a methylphenylpolysiloxane blocked with dimethylvinylsiloxy groups at both molecular chain ends represented by (vinyl group content = 2.1% by mass),
Formula: _HMe2SiO ( _Ph2SiO ) _SiMe2H
22.7 g (the above methylvinylphenylpolysiloxane and 1,3-divinyl-1,1,1,3-divinyl-1,1 of platinum, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane solution of 3,3-tetramethyldisiloxane complex (the amount of platinum metal in the present composition is 5.0 ppm by mass); 1-ethynyl-1-cyclohexanol (an amount that is 300 ppm by mass with respect to the present composition)
, 83.2 g of titanium oxide having an average primary particle size of 0.5 μm (SX-3103 manufactured by Sakai Chemical Industry Co., Ltd.), and 150 g of crushed quartz powder having an average particle size of 5 μm (Crystarite VX-52 manufactured by Tatsumori), and an average A pasty curable silicone composition was prepared by mixing 1.3 g of calcium stearate with a particle size of 7.5 μm (manufactured by Kawamura Kasei Co., Ltd., melt viscosity at 150° C. of 5 Pa·s).

When this composition was heated at 120° C. for 10 minutes, it was solid at 25° C. and had hot-melt properties such that it became fluid when heated to 100° C. or higher. When this composition was fluidized at 100° C. or higher and then heated at 150° C. for 10 minutes, it lost its hot-melt properties. This composition was injected into a Teflon (registered trademark) tube with a diameter of 14 mm and heated at 120° C. for 10 minutes to form cylindrical pellets with a height of 22 mm.

In Examples 1 to 8 of the present invention, both the granular curable silicone composition and the solid curable silicone composition achieved a low melt viscosity and excellent moldability and adhesive strength. It is. On the other hand, in Comparative Examples 1 to 4 lacking the (C0) component of the present invention, the melt viscosity was high and the handling workability was poor. In addition, in Comparative Examples 5 to 8 containing coarse particles having an average particle size of more than 1 μm instead of the component (B), the adhesive strength of the cured product is lowered, and sufficient adhesion to the substrate cannot be achieved. .

Claims (15)

(A0) a hot-melt silicone having a hydrosilylation-reactive group and/or a radical-reactive group ;
(B) an inorganic filler having an average particle size of 1.0 μm or less;
( C ) a hot-melt fatty acid metal salt, and (D) a curing agent, and
Regarding the kinematic viscosity (Vis _A ) when the component (A0) melts at 150 ° C. and the kinematic viscosity (Vis _C ) when the component ( C ) melts at 150 ° C., Vis _A > Vis _C ,
When component (A0) has a hydrosilylation-reactive group, component (D) contains a hydrosilylation reaction catalyst or an organic peroxide, and when component (A0) has a radical-reactive group, (D ) component contains an organic peroxide,
(B) component is 50% by mass or more of the whole,
However, the curable silicone composition does not substantially contain inorganic fillers that are coarse particles with an average particle size of 5.0 μm or more . 2. The curable silicone composition of claim 1, wherein Vis _A is in the range of 1 to 2,000 Pa.s and Vis _C is 1/5 or less of Vis _A. Claim 1, wherein the content of component ( C ) is in the range of 0.01 to 5.0 parts by mass when the sum of components (A0), (B), and (D) is 100 parts by mass. or the curable silicone composition of claim 2. Component (A0) is (A) hot-melt silicone fine particles having a softening point of 30° C. or higher,
4. The curability according to any one of claims 1 to 3, wherein 90% by mass or more of the component (B) is (B1) titanium oxide fine particles having an average particle size in the range of 0.10 to 0.75 μm. Silicone composition. 5. The curable silicone composition according to any one of claims 1 to 4, wherein component ( C ) is (C1) a fatty acid metal salt having a free fatty acid content of 5.0% or less. 6. The curable silicone composition according to any one of claims 1 to 5, wherein component ( C ) comprises at least one metal stearate. The (A0) component is (A ₁ ) a resinous organopolysiloxane, (A ₂ ) a crosslinked organopolysiloxane obtained by partially crosslinking at least one organopolysiloxane, and (A ₃ ) a resinous organosiloxane block and chain. 7. The curable silicone composition according to any one of claims 1 to 6, which is a block copolymer consisting of organosiloxane blocks, or silicone microparticles consisting of a mixture of at least two of these. Claims 1 to 7, wherein component (A0) is spherical silicone microparticles having an average primary particle diameter of 1 to 10 µm, wherein 10 mol% or more of the silicon-bonded organic groups in component (A0) are aryl groups. The curable silicone composition according to any one of Claims 1 to 3. A curable silicone composition according to any one of claims 1 to 8, which is in the form of a particulate composition. The curable silicone composition according to any one of claims 1 to 8 , which is molded into pellets or sheets.
A cured product obtained by curing the curable silicone composition according to any one of claims 1 to 10. Use of the cured product according to claim 11 as a light reflecting material. An optical semiconductor device comprising a light reflecting material formed from a cured product of the curable silicone composition according to any one of claims 1 to 10. 14. The optical semiconductor device according to claim 13, which is a chip scale package type optical semiconductor device. A method for molding a cured product comprising at least the following steps (I) to (III).
(I) a step of heating the curable silicone composition according to any one of claims 1 to 10 above the softening point of component (A0) to melt;
(II) A step of injecting the curable silicone composition obtained in step (I) into a mold, or a step of clamping the mold to spread the curable silicone composition obtained in step (I) over the mold; and (III) curing the curable silicone composition injected in step (II).