WO2025225682A1 - Silicone resin-coated silicone elastomer particles, manufacturing method therefor, and additive for organic resin and other applications - Google Patents

Abstract

The present invention is silicone resin-coated silicone elastomer particles including silicone elastomer particles and a silicone resin coating that covers a portion or the entirety of the surfaces of the silicone elastomer particles, wherein the silicone elastomer particles have a structure in which at least two silicon atoms are crosslinked by a C2-20 silalkylene group, the silicone resin coating includes one or more types of silicone resin selected from silicone resins consisting of a combination of one or more types of units selected from i) an M siloxane unit represented by R₃SiO_1/2 (where R is a monovalent organic group), ii) a D siloxane unit represented by R₂SiO_2/2 (where R is a monovalent organic group), iii) a T siloxane unit represented by RSiO_3/2 (where R is a monovalent organic group), and iv) a Q siloxane unit represented by SiO_4/2 (however, silicone resins that consist solely of T siloxane units are excluded), and the silicone resin has an epoxy group-including hydrocarbon group in a siloxane unit of the silicone resin, said siloxane unit being selected from the siloxane units i) to iii).

Description

Silicone resin-coated silicone elastomer particles, their manufacturing method, and additives for organic resins and other uses

The present invention relates to silicone resin-coated silicone elastomer particles and a method for producing the same. Furthermore, the present invention relates to additives for organic resins, paints or coating agents, curable organic resin compositions, cured products, semiconductor devices, and methods for producing semiconductor devices, all of which contain silicone resin-coated silicone elastomer particles.

Traditionally, various additives have been investigated for modifying the physical properties of a wide range of materials, including paints, coatings, thermosetting organic resins, and thermoplastic organic resins, specifically to reduce elasticity, thermal expansion, and molding shrinkage. In particular, with the recent trend toward miniaturization of various electronic devices, additives that can further reduce elasticity, thermal expansion, and molding shrinkage of the resin materials used in electronic components are being investigated.

JP 2013-010940 A International Publication No. 2021/149727 Japanese Patent Application Laid-Open No. 2021-075605 International Publication No. 2019/124418 International Publication No. 2020/137913

More specifically, as electronic devices such as mobile phones, smartphones, ultra-thin LCD displays, plasma TVs, and lightweight laptops become smaller, the semiconductor devices and other electronic components used in these devices are becoming increasingly integrated and mounted at higher densities. Demand for encapsulation of large-area devices, such as wafer-level packages and panel-level packages, is also increasing. Resin materials used in these electronic components can suffer from issues such as warping after molding and delamination between components during the solder reflow process, creating a need to reduce thermal stress during manufacturing and use. Furthermore, even when encapsulating multiple electronic components and wiring boards, such as engine control units (ECUs) and automotive integrated circuits (ICs), thermal stresses generated between the resin and the electronic components or wiring boards during manufacturing and use can cause delamination between the components, creating a need to reduce thermal stress. Incidentally, thermal stress occurs when residual strain occurs due to volumetric changes in the encapsulating composition. To reduce this residual strain, it is essential to suppress both the cure shrinkage caused by volume reduction due to the polymerization/crosslinking reaction of the encapsulating resin composition and the thermal shrinkage caused by cooling after encapsulation.

For example, Patent Document 1 considers increasing the filler content of epoxy resins in order to reduce thermal stress. Increasing the filler content can reduce the thermal expansion coefficient of the cured epoxy resin composition, but when the support surface area is large, as in wafer-level packages and panel-level packages, the effect of suppressing warpage may not be sufficient. Furthermore, the elastic modulus of the cured product increases and its strength decreases, which can lead to problems such as damage to Si chips and substrates during manufacturing processes such as solder reflow processes, or during heat cycle tests during use.

Patent Document 2 discloses another method for reducing thermal stress, in which an epoxy-modified silicone is added to an epoxy resin to reduce the modulus of elasticity of the cured epoxy resin composition. While this method is effective in reducing thermal stress, it does not sufficiently reduce the coefficient of thermal expansion (linear expansion coefficient). In particular, it does not sufficiently reduce the coefficient of thermal expansion at temperatures higher than the glass transition temperature.

Furthermore, methods have been known in which silicone rubber particles are added to reduce the coefficient of thermal expansion (linear expansion coefficient) and mold shrinkage, or to reduce thermal stress by lowering the modulus of elasticity, but the effects have been insufficient (see, for example, Comparative Example 2-5, described below). Silicone rubber particles coated with silicone resin (see, for example, Comparative Examples 2-1, 2-2, and 2-3, described below) and silicone rubber particles with epoxy groups introduced (see, for example, Comparative Example 2-4, described below) have also been investigated, but the reduction in the coefficient of thermal expansion (linear expansion coefficient) and mold shrinkage remains insufficient. Furthermore, as in Patent Document 3, silicone rubber particles containing a silicone resin composed of epoxy groups and T units have also been investigated, but this is insufficient to improve thermal stress, and furthermore, there are problems with the manufacturing process. Specifically, trialkoxyorganosilane is used as the T unit, but aggregation and gelation can occur during the coating process (see, for example, Comparative Example 1-1, described below). Similarly, the present applicants have proposed organic resin additives containing silicone elastomer particles coated with a silicone resin containing branched units such as Q units and T units (see, for example, Patent Documents 4 and 5). These silicone elastomer particles have excellent dispersibility in organic resin varnish and have a certain effect on stress relaxation when combined with glass fabric, but there is still room for further improvement in terms of reducing shrinkage, thermal expansion, or elastic modulus during molding of epoxy resins that do not contain volatile solvents, as described below (Comparative Examples 2-1, 2-2, and 2-3).

As such, in a wide range of materials, including resin materials used in electronic components, paints, coatings, thermosetting organic resins, and thermoplastic organic resins, there is a need to alleviate internal stress in order to prevent warping and the resulting peeling that can occur during their manufacture or use. There is a demand for additives that can effectively reduce shrinkage, thermal expansion, or elasticity during molding. Such additives are also required to have resistance to deterioration, so that they are less likely to affect the deterioration of the material they are added to over long periods of use. Furthermore, there is a demand for additives that produce less gel, which can hinder manufacturing, when manufactured.

The present invention therefore aims to provide silicone resin-coated silicone elastomer particles that can contribute to stress relaxation of the material to which they are added while maintaining dispersibility in the material, and that also have resistance to deterioration, as well as a method for producing the same. The present invention also aims to provide additives for organic resins, paints or coating agents, curable organic resin compositions, cured products, and semiconductor devices containing silicone resin-coated silicone elastomer particles that can reduce molding shrinkage, thermal expansion coefficient, and elastic modulus, as well as a method for producing the semiconductor devices.

[1]
Silicone resin-coated silicone elastomer particles comprising silicone elastomer particles and a silicone resin coating that coats a part or all of the surface of the silicone elastomer particles,
the silicone elastomer particles have a structure in which at least two silicon atoms are crosslinked by a silalkylene group having 2 to 20 carbon atoms;
The silicone resin coating
i) M siloxane units represented by R ₃ SiO _1/2 (R is a monovalent organic group); ii) D siloxane units represented by R ₂ SiO _2/2 (R is a monovalent organic group);
iii) T siloxane units represented by RSiO _3/2 (R is a monovalent organic group), and
iv) Q siloxane units represented by SiO _4/2 ;
and one or more silicone resins selected from the group consisting of one or a combination of two or more silicone resins selected from the group consisting of:
The silicone resin-coated silicone elastomer particles have an epoxy group-containing hydrocarbon group in a siloxane unit selected from the siloxane units i) to iii) of the silicone resin.
[2]
The silicone resin-coated silicone elastomer particles according to [1], wherein the amount of the silicone resin coating is in the range of 5.0 to 40.0 parts by mass per 100 parts by mass of the silicone elastomer particles.
[3]
The silicone resin-coated silicone elastomer particles according to [1] or [2], which have an average primary particle diameter of 0.1 to 100 μm as measured by a laser diffraction scattering method.
[4]
The silicone elastomer particles coated with a silicone resin according to any one of [1] to [3], wherein the silicone elastomer particles in a state not coated with the silicone resin coating have a JIS-A hardness of 80 or less and a JIS-E hardness of 1 or more, as measured by curing a crosslinkable composition for forming silicone elastomer particles before curing into a sheet.
[5]
The silicone resin-coated silicone elastomer particles according to any one of [1] to [4], wherein the content of silicon-bonded hydrogen per unit mass is 300 ppm or less.
[6]
the silicone resin coating comprises a DQ silicone resin composed of D siloxane units represented by R ¹ ₂ SiO _2/2 (wherein R ¹ is independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms and an epoxy group, or an aryl group having 6 to 20 carbon atoms and an epoxy group), and Q siloxane units represented by SiO _4/2 ;
The silicone resin-coated silicone elastomer particles according to any one of [1] to [5], wherein the mass ratio of the D siloxane units to the Q siloxane units is within the range of 8:2 to 0.8:9.2.
[7]
the silicone resin coating comprises a DQ silicone resin formed from a condensation reaction product of a diorganodialkoxysilane and a tetraalkoxysilane;
At least a portion of the silane in the diorganodialkoxysilane has an epoxy group-containing hydrocarbon group,
The silicone resin-coated silicone elastomer particles according to any one of [1] to [6], wherein the molar ratio of the D units derived from the diorganodialkoxysilane to the Q units derived from the tetraalkoxysilane is within the range of 8:2 to 0.8:9.2.
[8]
Regarding the silicone elastomer particles in a state where they are not coated with the silicone resin coating, the crosslinkable composition for forming the silicone elastomer particles before curing is
(a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in each molecule;
(b) an organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms in each molecule; and
(c) a hydrosilylation reaction catalyst;
Contains
the molar ratio of the content of alkenyl groups (Alk (mol)) in the component (a) to the content of hydrogen atoms bonded to silicon atoms (H (mol)) in the component (b) is H/Alk=0.5 to 1.5;
The silicone resin-coated silicone elastomer particles according to any one of [1] to [7], which are crosslinkable compositions in the range of
[9]
A method for producing silicone resin-coated silicone elastomer particles, comprising:
The manufacturing method includes:
Step (I):
(a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule;
(b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule, and (d) a silane-based compound;
emulsifying the mixture in water;
Step (II):
(c) curing the emulsion obtained in step (I) in the presence of a hydrosilylation reaction catalyst to obtain silicone elastomer particles; and
Step (III):
a step of coating a part or all of the surfaces of the silicone elastomer particles with the (d) silane-based compound and, optionally, the (e) silane-based compound-containing silicone resin added during the step (III), simultaneously with or after the step (II);
Including,
When the (e) silane-based compound is added, at least one of the (d) silane-based compound and the (e) silane-based compound contains a hydrolyzable silane having an epoxy group-containing hydrocarbon group,
When the silane-based compound (e) is not added, the silane-based compound (d) contains a hydrolyzable silane having an epoxy group-containing hydrocarbon group.
[10]
The (d) silane-based compound includes tetraalkoxysilane or a condensation product thereof,
The method according to [9], wherein the hydrolyzable silane having an epoxy group-containing hydrocarbon group or a condensation reaction product thereof includes a diorganodialkoxysilane having an epoxy group-containing hydrocarbon group or a condensation reaction product thereof.
[11]
An additive for organic resins, comprising the silicone resin-coated silicone elastomer particles according to any one of [1] to [8].
[12]
The organic resin additive according to [11], wherein the organic resin contains an epoxy resin.
[13]
A paint or coating agent comprising the silicone resin-coated silicone elastomer particles according to any one of [1] to [8].
[14]
The paint or coating agent according to [13], wherein the organic resin comprises an epoxy resin.
[15]
A curable organic resin composition comprising the silicone resin-coated silicone elastomer particles according to any one of [1] to [8] and a curable organic resin.
[16]
The curable organic resin composition according to [15], wherein the curable organic resin contains an epoxy resin.
[17]
A cured product obtained by curing the curable organic resin composition according to [15].
[18]
A semiconductor device comprising the cured product according to [17].
[19]
A method for manufacturing a semiconductor device, comprising curing the curable organic resin composition according to [15].

The present invention provides silicone resin-coated silicone elastomer particles that maintain dispersibility in the material to which they are added, contribute to stress relief in the material, and are also resistant to deterioration, as well as a method for producing the same. The present invention also provides additives for organic resins, paints or coating agents, curable organic resin compositions, cured products, and semiconductor devices containing silicone resin-coated silicone elastomer particles that are capable of reducing molding shrinkage, thermal expansion coefficient, and elastic modulus, as well as methods for producing the semiconductor devices.

1 is a photograph of a fracture surface of a cured epoxy resin material (Comparative Example 2-1) to which the silicone resin-coated silicone elastomer particles of Comparative Example 1-2 have been added, taken at 2500x magnification using a scanning electron microscope (SEM). 1 is a photograph of a fracture surface of a cured epoxy resin material (Example 2-3) to which the silicone resin-coated silicone elastomer particles of Example 1-3 have been added, taken at 2500x magnification using a scanning electron microscope (SEM).

Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail, but the present invention is not limited to this embodiment.
It should be noted that the upper and lower limit values of the numerical ranges described herein can be combined in any combination. For example, when a numerical range is described as "preferably 30 to 100, more preferably 40 to 80," the ranges "30 to 80" and "40 to 100" are also included in the numerical ranges described herein. Furthermore, when a numerical range is described as "preferably 30 or more, more preferably 40 or more, and preferably 100 or less, more preferably 80 or less," the ranges "30 to 80" and "40 to 100" are also included in the numerical ranges described herein.
In addition, as a numerical range described in this specification, for example, "60 to 100" means a range of "60 or more and 100 or less."

<Component (A): Silicone Resin-Coated Silicone Elastomer Particles>
The silicone resin-coated silicone elastomer particles of this embodiment are silicone resin-coated silicone elastomer particles that include silicone elastomer particles and a silicone resin coating that coats a part or all of the surface of the silicone elastomer particles. In addition, in the silicone resin-coated silicone elastomer particles of this embodiment, the silicone elastomer particles have a structure in which at least two silicon atoms are crosslinked by a silalkylene group having 2 to 20 carbon atoms,
The silicone resin coating
i) M siloxane units represented by R ₃ SiO _1/2 (R is a monovalent organic group);
ii) D siloxane units represented by R ₂ SiO _2/2 (R is a monovalent organic group);
iii) T siloxane units represented by RSiO _3/2 (R is a monovalent organic group), and
iv) Q siloxane units represented by SiO _4/2 ;
and one or more silicone resins selected from the group consisting of one or a combination of two or more silicone resins selected from the group consisting of:
The silicone resin has an epoxy group-containing hydrocarbon group in a siloxane unit selected from the siloxane units i) to iii) of the silicone resin.

[Silicone elastomer particles before coating]
The silicone elastomer particles have a structure in which at least two silicon atoms are crosslinked by a silalkylene group having 2 to 20 carbon atoms. Such a silalkylene crosslinked structure is preferably formed between different siloxane molecules by the hydrosilylation reaction of an alkenyl group having 2 to 20 carbon atoms with a silicon-bonded hydrogen atom. In this embodiment, the silalkylene group that crosslinks a silicon atom with another silicon atom in the siloxane that constitutes the silicone elastomer particles is preferably a silalkylene group having 2 to 16 carbon atoms, more preferably 2 to 8 carbon atoms, and particularly preferably an ethylene group, propylene group, butylene group, or hexylene group.

The silicone elastomer particles according to this embodiment are not particularly limited in terms of average primary particle diameter before being coated with silicone resin, but it is preferable that the average primary particle diameter measured by laser diffraction scattering be 0.1 to 99 μm. Such silicone elastomer particles can be further coated on part or all of their surfaces with silicone resin and further classified as necessary to ultimately provide silicone resin-coated silicone elastomer particles having an average primary particle diameter measured by laser diffraction scattering of 0.1 to 100 μm. It goes without saying that after coating, the average primary particle diameter of the particles increases compared to the silicone elastomer particles before coating.

The shape of the silicone elastomer particles according to this embodiment can be, for example, spherical, true spherical, ellipsoidal, or irregular, with spherical and true spherical shapes being particularly preferred. In this embodiment, an aqueous suspension containing spherical silicone elastomer particles coated with silicone resin can be obtained in a single reaction vessel by emulsifying hydrolyzable silanes together with a cross-linking reactive silicone raw material. Furthermore, spherical silicone resin-coated silicone elastomer particles can be directly produced by drying the aqueous suspension using a vacuum dryer, hot air circulation oven, or spray dryer. Therefore, it is not necessarily necessary to separately produce uncoated silicone elastomer particles and coat their surfaces.

The silicone elastomer particles according to this embodiment are elastomer particles having elasticity from the viewpoint of technical effects such as stress relaxation when blended with a material to which they are added, such as an organic resin. Preferably, when a crosslinkable composition for forming silicone elastomer particles before the silicone elastomer particles are cured into a sheet, the cured product has a JIS-A hardness of 80 or less and a JIS-E hardness of 1 or more. The JIS-A hardness is determined by the JIS
The hardness is measured using a JIS-A hardness tester specified in JIS K6253, and the JIS-E hardness is measured using a JIS-E hardness tester specified in JIS K6253. When the JIS-A hardness and JIS-E hardness of a rubber sheet obtained by curing a crosslinkable composition for forming silicone elastomer particles into a sheet are measured within the above-mentioned ranges, the resulting silicone elastomer particles are sufficiently suppressed in aggregation and tend to be rich in fluidity, dispersibility, dryness, smoothness, and softness. Furthermore, by setting the JIS-A hardness and JIS-E hardness within the above-mentioned ranges, stress relaxation can be further improved when the elastomer particles are blended with various materials such as organic resins, and excellent handling and workability can be achieved after coating with the silicone resin. The upper limit of the JIS-A hardness of the elastomer particles is 80 or less, preferably 50 or less, and more preferably 40 or less. Similarly, the JIS-E hardness, which corresponds to the lower limit of the hardness of the elastomer particles, is preferably 1 or more, and more preferably 2 or more or 3 or more in practical terms.

In this embodiment, the upper limit of the hardness of the cured product is specified in terms of JIS-A hardness and the lower limit is specified in terms of JIS-E hardness. This is because, when the hardness of the cured product of the composition is in a relatively high range, the degree of hardness can be easily expressed by JIS-A hardness, and, when the hardness of the cured product is in a relatively low range, the degree of hardness can be easily expressed by JIS-E hardness.
In addition, in a cured product obtained by curing the crosslinkable composition for forming silicone elastomer particles into a sheet, if the JIS-A hardness is 40, the JIS-E hardness may be 50; if the JIS-A hardness is 25, the JIS-E hardness may be 37; and if the JIS-A hardness is 8, the JIS-E hardness may be 23.

The silicone elastomer particles according to this embodiment may further have a content of silicon-bonded hydrogen atoms (hereinafter also referred to as silicon-bonded hydrogen) per unit mass of 300 ppm or less. The silicon-bonded hydrogen content is preferably 250 ppm or less, and even more preferably 200 ppm or less. It is further preferably 150 ppm or less, more preferably 100 ppm or less, more preferably 50 ppm or less, and even more preferably 20 ppm or less. If the silicone elastomer particles according to this embodiment contain a large amount of silicon-bonded hydrogen, crosslinking reactions with reactive functional groups remaining in other silicone elastomer particles may proceed, potentially resulting in aggregation of the silicone elastomer particles or silicone resin-coated silicone elastomer particles over time. Furthermore, in this embodiment, reducing the silicon-bonded hydrogen in the silicone elastomer particles effectively suppresses the generation of hydrogen gas that can occur during long-term storage of these particles.

A typical method for measuring silicon-bonded hydrogen in silicone elastomer particles is to contact them with an alkali and then use gas chromatography (headspace method). For example, an equal amount of 40% potassium hydroxide in ethanol solution per unit mass of silicone elastomer particles is added, allowed to stand for one hour, and the hydrogen gas evolved up to the end of the reaction is collected. The amount of captured hydrogen generated is then measured and quantified using headspace gas chromatography (TCD is preferred as the detector), making it possible to identify the silicon-bonded hydrogen content (ppm) per unit mass.

[Crosslinkable composition for forming silicone elastomer particles]
The silicone elastomer particles have a structure in which at least two silicon atoms in a molecule are crosslinked by a silalkylene group having 2 to 20 carbon atoms, and can be obtained by curing, through a hydrosilylation reaction, a crosslinkable composition containing the following components:
(a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in each molecule;
(b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in each molecule; and (c) a hydrosilylation reaction catalyst.

Component (a) is an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms per molecule. There are no particular limitations on its structure, and it may be one or more structures selected from linear, cyclic, network, and partially branched linear. Linear organopolysiloxanes are particularly preferred as component (a). Furthermore, the viscosity of component (a) is preferably within a range that allows the crosslinkable composition to be dispersed in water or dispersible using a spray dryer or similar. Specifically, the viscosity is preferably within a range of 1 to 100,000 mPa·s at 25°C, and particularly preferably within a range of 1 to 10,000 mPa·s.

From the viewpoint of dispersibility of the silicone elastomer particles, component (a) is preferably a linear organopolysiloxane in which the content of dimethylsiloxane units represented by the formula: —(CH ₃ ) ₂ SiO— accounts for 90 mol % or more of all siloxane units other than siloxane units at the molecular terminals. Similarly, from the viewpoint of improving contact failures in electronic components and the like equipped with resin components after blending the resulting silicone elastomer particles, it is also preferable to remove in advance from component (a) any cyclic or linear organopolysiloxanes with a low degree of polymerization (degree of polymerization 3 to 20) other than intentionally added low polymers by solvent washing, stripping, thin-film distillation, or the like. Furthermore, component (a) may be used alone, or two or more types of organohydrogenpolysiloxanes may be used.

Examples of alkenyl groups having 2 to 20 carbon atoms in component (a) include vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecenyl, and icocenyl. From the standpoints of reactivity and cohesion, the alkenyl group preferably has 2 to 16 carbon atoms or 2 to 8 carbon atoms, with vinyl or hexenyl being particularly preferred. Furthermore, the alkenyl groups are preferably located at the molecular chain terminals of the organopolysiloxane, but may also be located on side chains or both. Examples of groups bonded to silicon atoms other than alkenyl groups include unsubstituted or substituted monovalent hydrocarbon groups such as alkyl groups such as methyl, ethyl, propyl, and butyl; cycloalkyl groups such as cyclopentyl and cyclohexyl; aryl groups such as phenyl, tolyl, and xylyl; aralkyl groups such as benzyl, phenethyl, and 3-phenylpropyl; and halogenated alkyl groups such as 3-chloropropyl and 3,3,3-trifluoropropyl.

Preferably, component (a) is a linear organopolysiloxane represented by the following chemical formula (1).

In formula (1), R ¹¹ are each independently an unsubstituted or halogen-substituted alkyl group having 1 to 20 carbon atoms (e.g., methyl group), an aryl group having 6 to 22 carbon atoms (e.g., phenyl group), or a hydroxyl group, and are industrially preferably a methyl group or a phenyl group. ^{R a} is an alkenyl group having 2 to 20 carbon atoms, and is particularly preferably a vinyl group or a hexenyl group. R is a group represented by R ¹¹ or R ^a . m is a number of 0 or greater, and n is a number of 1 or greater. Here, m, n, and R are numbers such that the content of vinyl (CH ₂ ═CH—) moieties in the alkenyl groups having 2 to 20 carbon atoms in the organopolysiloxane molecule represented by formula (1) above is 0.02 to 5.0 mass%, preferably 0.03 to 3.0 mass%, and that the viscosity of component (a) is 1 to 10,000 mPa·s at 25°C.

Component (a) may be an organopolysiloxane represented by the following structural formula (2) having hexenyl groups at both molecular chain terminals and in side chains, or may be an organopolysiloxane in which some or all of the hexenyl groups in structural formula (2) are vinyl groups.
(In formula (2), m1 is a number equal to or greater than 0, and n1 is a positive number. m1 is a number such that the content of vinyl (CH ₂ ═CH—) moieties in hexenyl groups (—(CH ₂ ) ₄ CH═CH ₂ ) in the molecule represented by formula (2) is in the range of 0.5 to 3.0 mass %, more preferably 1.0 to 2.0 mass %. Furthermore, m1+n1 is a number such that the viscosity of the organopolysiloxane represented by formula (2) at 25° C. is 20 mPa·s or greater, more preferably 100 to 500 mPa·s.)

Component (a) may also be a branched organopolysiloxane having an alkenyl group at the molecular chain terminal, represented by (R ^a R ¹¹ ₂ SiO) ₄ Si. In this formula, R ^a is an alkenyl group having 2 to 20 carbon atoms, and each R ¹¹ is independently an unsubstituted or halogen-substituted alkyl group having 1 to 20 carbon atoms (e.g., methyl group), an aryl group having 6 to 22 carbon atoms (e.g., phenyl group), or a hydroxyl group. More specifically,
(ViMe ₂ SiO) ₄ Si, and (HexMe ₂ SiO) ₄ Si
In the formula, Vi represents a vinyl group, Me represents a methyl group, and Hex represents a hexenyl group.

Examples of component (a) include linear, cyclic, or branched organopolysiloxanes represented by the following formula, in which some or all of the vinyl groups may be hexenyl groups.
(In the above formula, b and c are integers from 0 to 3 that satisfy b+c=3, d is a positive number, e is 0 or a positive number, and 2b+e≧2. ^R11 is the same as in formula (1) above.)
(In the above formula, f is a positive number of 2 or more, g is 0 or a positive integer, and f+g is 4 to 8. R ¹¹ is the same as in formula (1) above.)
(In the above formula, h is 1, 2, or 3, i is 0, 1, or 2, and h+i=3; j, k, and L are positive numbers. ^R11 is the same as in formula (1) above.)
However, b and e in the formula representing the linear organopolysiloxane, f in the formula representing the cyclic organopolysiloxane, and h in the formula representing the branched organopolysiloxane are numbers such that the content of vinyl (CH ₂ ═CH—) moieties in the molecule is in the range of 0.5 to 3.0 mass%, more preferably 1.0 to 2.0 mass%. Furthermore, b, e, f, and h in each formula are numbers in the range such that the viscosity of the organopolysiloxane represented by the formula at 25° C. is 20 mPa·s or more, more preferably 100 to 500 mPa·s.

Component (b) is an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms (hereinafter also referred to as silicon-bonded hydrogen atoms) per molecule, and serves as a crosslinker for component (a). It more preferably has at least three silicon-bonded hydrogen atoms per molecule, and the bonding positions of these hydrogen atoms within the molecule are not particularly limited. From the standpoint of improving contact failures in electronic components and other devices equipped with resin components after the resulting silicone elastomer particles are compounded, it is also preferable to remove in advance any cyclic or linear organopolysiloxanes with low degrees of polymerization (degree of polymerization 3 to 20) other than the intentionally added low polymers from component (b) by solvent washing, stripping, thin-film distillation, or the like. Furthermore, component (b) may be used alone, or two or more types of organohydrogenpolysiloxanes may be used.

Examples of organic groups other than hydrogen atoms that are bonded to silicon atoms contained in component (b) include alkyl groups such as methyl, ethyl, propyl, butyl, and octyl, and aryl groups such as phenyl, with methyl being preferred. Furthermore, the molecular structure of the organohydrogenpolysiloxane of component (b) can be linear, branched, or branched cyclic, or a combination of one or more of these. The number of silicon-bonded hydrogen atoms per molecule is the average value for all molecules.

Examples of component (b) include linear, cyclic, or branched polyorganohydrogensiloxanes represented by the following formula:
(In the formula, m' is 0 or 1, n2 is 2 or 3, and m'+n'=3, p is 0 or a positive number, q is 0 or a positive number, and 2m'+q≧2. ^R11 is the same as in formula (1) above.)
(In the formula, r is a positive number of 2 or more, s is 0 or a positive number, and r+s is 4 to 8. ^R11 is the same as in formula (1) above.)
(In the formula, t is 1, 2, or 3, u is 0, 1, or 2, and (t+u)=3; v, w, and x are positive numbers; and ^R11 is the same as in formula (1) above.)
Component (b) also includes T-branched polyorganohydrogensiloxanes (R ¹¹ is the same as in formula (1) above) containing at least one T-branched unit selected from (HSiO _3/2 ) units or (R ¹¹ SiO _3/2 ) units.

The viscosity of component (b) at 25°C is 1 to 1,000 mPa·s, preferably 5 to 500 mPa·s. When the viscosity of component (b) at 25°C is 1 mPa·s or more, it is possible to effectively prevent component (b) from volatilizing from the crosslinkable composition containing it. Furthermore, when the viscosity of component (b) at 25°C is 1,000 mPa·s or less, it is possible to prevent the curing time of the crosslinkable composition containing such component (b) from becoming too long and to suppress the occurrence of poor curing. Examples of such component (b) include, but are not limited to, a dimethylsiloxane-methylhydrogensiloxane copolymer capped at both ends with trimethylsiloxy groups, a dimethylsiloxane-methylhydrogensiloxane copolymer capped at both ends with dimethylhydrogensiloxy groups, a dimethylpolysiloxane capped at both ends with dimethylhydrogensiloxy groups, a methylhydrogenpolysiloxane capped at both ends with trimethylsiloxy groups, a cyclic methylhydrogenpolysiloxane, a cyclic methylhydrogensiloxane-dimethylsiloxane copolymer, and a T-branched polymethylhydrogensiloxane.

Here, the molar ratio (=reaction ratio in the hydrosilylation reaction) of the content of alkenyl groups (Alk (mol)) in component (a) to the content of silicon-bonded hydrogen atoms (H (mol)) in component (b), H/Alk, is preferably in the range of 0.5 to 1.5. The lower limit of H/Alk is preferably 0.60 or more, and the upper limit is 1.50 or less, and more preferably 1.30 or less. If the upper limit of H/Alk exceeds the above value, unreacted silicon-bonded hydrogen atoms are likely to remain after the reaction. Because these are curing reactive groups, if a large amount remains in the particles, they can cause crosslinking reactions between particles over time, resulting in aggregation and poor dispersion of the resulting silicone elastomer particles or silicone resin-coated silicone elastomer particles. Furthermore, if reactive hydrogen atoms remain, they can cause hydrogen gas generation over time. Particularly preferably, when the H/Alk value is in the range of 0.6 to 1.30, the curing reactive groups are completely consumed, the crosslinking reaction is terminated, and aggregation between particles over time can be effectively suppressed.
The alkenyl group content (Alk (mol)) means the content (amount of substance (mol)) of vinyl groups in the alkenyl groups.

Component (c) is a hydrosilylation catalyst that promotes the addition reaction (hydrosilylation reaction) between silicon-bonded alkenyl groups present in the crosslinkable composition and silicon-bonded hydrogen atoms. Preferred hydrosilylation catalysts are those containing platinum-based metals, and specific examples include chloroplatinic acid, alcohol-modified chloroplatinic acid, olefin complexes of chloroplatinic acid, complexes of chloroplatinic acid and ketones, complexes of chloroplatinic acid and vinylsiloxanes, platinum tetrachloride, platinum fine powder, solid platinum supported on an alumina or silica carrier, platinum black, olefin complexes of platinum, alkenylsiloxane complexes of platinum, carbonyl complexes of platinum, and platinum catalysts containing these platinum-based catalysts in powders of thermoplastic organic resins such as methyl methacrylate resin, polycarbonate resin, polystyrene resin, and silicone resin. In particular, platinum alkenylsiloxane complexes such as a complex of chloroplatinic acid and divinyltetramethyldisiloxane, a complex of chloroplatinic acid and tetramethyltetravinylcyclotetrasiloxane, a platinum divinyltetramethyldisiloxane complex, and a platinum tetramethyltetravinylcyclotetrasiloxane complex are preferably used. Non-platinum metal catalysts such as iron, ruthenium, and iron/cobalt may also be used as catalysts to promote the hydrosilylation reaction.

Component (c) may be added to the crosslinkable composition in any catalytic amount, and typically, the amount is such that the amount of platinum-based metal contained in component (c) is in the range of 1 to 1,000 ppm, and more preferably in the range of 5 to 500 ppm, relative to the total mass of the crosslinkable composition. The platinum content in the silicone elastomer particles may also be reduced by washing the silicone elastomer particles with an aqueous solution (preferably 30°C to 99°C) of one or more surfactants, such as polyoxyethylene alkyl ether or diethylhexyl sodium sulfosuccinate.

The timing of adding component (c) to the crosslinkable composition can be selected depending on the method for forming the silicone elastomer particles. It may be added to the composition beforehand, or component (a) or component (b) may be supplied from different spray lines and added to either one of them and mixed during spraying. Similarly, when the silicone elastomer particles are formed via an aqueous suspension formed by emulsifying them in water, component (c) may be added to the crosslinkable composition beforehand, or an emulsion containing component (c) may be added separately to the water.

The crosslinkable composition may contain a cure retarder, such as a hydrosilylation reaction inhibitor. Examples of such cure retarders include acetylene compounds, enyne compounds, organic nitrogen compounds, organic phosphorus compounds, and oxime compounds. Specific compounds include alkyne alcohols such as 2-methyl-3-butyn-2-ol, 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-pentyn-3-ol, 2-phenyl-3-butyn-2-ol, and 1-ethynyl-1-cyclohexanol (ETCH); 3-methyl-3-trimethylsiloxy-1-butyne, 3-methyl-3-trimethylsiloxy-1-pentyne, 3,5-dimethyl-3-trimethylsiloxy-1-hexyne, and 3-methyl-3-penten-1-yne. Examples include ene-yne compounds such as 3,5-dimethyl-3-hexen-1-yne; and alkenylsiloxanes such as 1-ethynyl-1-trimethylsiloxycyclohexane, bis(2,2-dimethyl-3-butynoxy)dimethylsilane, methyl(tris(1,1-dimethyl-2-propynyloxy))silane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, and 1,3,5,7-tetramethyl-1,3,5,7-tetrahexenylcyclotetrasiloxane. The amount added is within the range of 0.001 to 5 parts by mass per 100 parts by mass of component (a), but can be appropriately determined depending on factors such as the type of cure retarder used and the properties and amount of the hydrosilylation reaction catalyst used.

The crosslinkable composition may contain components other than those described above, provided that the technical effects of the present invention are not impaired. For example, the crosslinkable composition may contain 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 hexamethyldisiloxane, octamethyltrisiloxane, and decamethyltetrasiloxane; esters such as ethyl acetate, butyl acetate, and propylene glycol monomethyl ether acetate; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; organic solvents such as polydimethylsiloxane and polydimethyldiphenylsiloxane. The composition may contain non-reactive organopolysiloxanes (including linear or cyclic organopolysiloxanes with a low viscosity of about 0.5 to 10 mPa·s at 25°C); antioxidants such as phenols, quinones, amines, phosphorus, phosphite, sulfur, or thioethers; light stabilizers such as triazoles or benzophenones; flame retardants such as phosphate esters, halogens, phosphorus, or antimony; one or more antistatic agents such as cationic surfactants, anionic surfactants, or nonionic surfactants; dyes; pigments, etc.
The crosslinkable composition for forming silicone elastomer particles may or may not contain a component such as silane for forming a silicone resin coating.

[Coating with silicone resin]
The silicone resin-coated silicone elastomer particles of this embodiment contain a silicone resin coating that coats a part or the whole of the surface of the silicone elastomer particles. Specifically, the silicone resin coating is
i) M siloxane units represented by R ₃ SiO _1/2 (R is a monovalent organic group); ii) D siloxane units represented by R ₂ SiO _2/2 (R is a monovalent organic group);
iii) T siloxane units represented by RSiO _3/2 (R is a monovalent organic group), and
iv) Q siloxane units represented by SiO _4/2 ;
The silicone resin-coated silicone elastomer particles of this embodiment contain one or more silicone resins (excluding silicone resins consisting only of T siloxane units) selected from the group consisting of one or a combination of two or more silicone resins selected from the group consisting of i) to iii) of the siloxane units of the silicone resin, wherein the silicone resin has an epoxy group-containing hydrocarbon group in a siloxane unit selected from the group consisting of i) to iii).

In this embodiment, the silicone resin coating contains the above-mentioned silicone resin, which allows the silicone resin coating to maintain dispersibility in the material to which it is added, contribute to stress relaxation of the material, and also provides resistance to deterioration.
More specifically, coating part or all of the surface of the silicone elastomer particles with a silicone resin coating effectively suppresses secondary aggregation between particles, improving dispersibility, handling, and compounding stability. Furthermore, when the silicone resin contains an epoxy group-containing hydrocarbon group in a siloxane unit selected from siloxane units i) to iii), when the silicone resin-coated silicone elastomer particles are mixed with a target material, the epoxy groups of the silicone resin-coated silicone elastomer particles serve as reaction sites with the material, improving adhesion to the resin. This prevents the particle-resin interface from peeling when the added resin is subjected to external or internal impact or strain, allowing the impact or strain to be absorbed internally within the added elastomer particles. Furthermore, when the powder particles fracture, the internal stress is relieved, contributing to crack resistance and toughness. Furthermore, the improved adhesion effectively reduces molding shrinkage, the thermal expansion coefficient, and the elastic modulus, contributing to stress relaxation in the material. Furthermore, due to the improved adhesion, the additive has a resistance to deterioration, meaning that the additive is less likely to affect the deterioration of the material over a long period of use.
In this embodiment, the silicone resin contained in the silicone resin coating does not include silicone resins consisting only of T siloxane units. However, when silicone elastomer particles are coated with a silicone resin consisting only of T siloxane units, they tend to be prone to gelation during production or aggregation after production. Furthermore, when silane undergoes a condensation reaction on the surface of the silicone elastomer particles, the condensation reaction is difficult to control, or the condensation reaction tends to result in problems such as solidification. Furthermore, silicone elastomer particles containing a silicone resin consisting of epoxy groups and T siloxane units tend to have difficulty in fully exhibiting the properties of the silicone elastomer particles due to the T siloxane units, and may be insufficient to improve thermal stress.

In this embodiment, the amount of silicone resin other than the above is preferably less than 5% by mass, less than 3% by mass, particularly less than 1% by mass, based on the total amount of silicone resin used for the silicone resin coating.Most preferably, no components that provide other silicone resins are intentionally added, and it is most preferable that no other silicone resins are contained on the surface of the silicone elastomer particles.If other silicone resins (for example, silsesquioxane resins represented by RSiO3 _/2 ) are contained, the obtained silicone resin-coated silicone elastomer particles may be prone to scattering or adhesion to the container during handling, or the problem of aggregation may not be fully resolved, resulting in poor handling and workability.
Furthermore, the silicone resin coating preferably contains less than 5% by mass of resins other than silicone resin, preferably less than 3% by mass, and particularly preferably less than 1% by mass, based on the total amount of the silicone resin coating. Most preferably, no resins other than silicone resin are intentionally added, and it is most preferable that the surfaces of the silicone elastomer particles contain no other silicone resins whatsoever.

In this embodiment, examples of the silicone resin contained in the silicone resin coating include a silicone resin composed of M siloxane units and T siloxane units, a silicone resin composed of M siloxane units and Q siloxane units, a silicone resin composed of D siloxane units and T siloxane units, a silicone resin composed of D siloxane units and Q siloxane units, a silicone resin composed of T siloxane units and Q siloxane units, a silicone resin composed of Q siloxane units, a silicone resin composed of M siloxane units, D siloxane units, and T siloxane units, a silicone resin composed of M siloxane units, T siloxane units, and Q siloxane units, a silicone resin composed of M siloxane units and Q siloxane units, a silicone resin composed of D siloxane units, T siloxane units, and Q siloxane units, and a silicone resin composed of M siloxane units, D siloxane units, T siloxane units, and Q siloxane units.
Among these, in this embodiment, DQ silicone resins composed of D siloxane units and Q siloxane units, DT silicone resins composed of D siloxane units and T siloxane units, TQ silicone resins composed of T siloxane units and Q siloxane units, and DTQ silicone resins composed of D siloxane units, T siloxane units, and Q siloxane units are preferred. This is because the silanols generated by hydrolysis of the Q units form a three-dimensional structure, increasing the reaction efficiency with the silanols of the D units and T units, thereby allowing for efficient introduction of functional groups, reducing unreacted silane remaining in water, and suppressing aggregation. From the same perspective, DQ silicone resins composed of D siloxane units and Q siloxane units are more preferred.

In this embodiment, the siloxane units having an epoxy group-containing hydrocarbon group in the siloxane units are selected from i) to iii) M, D, and T siloxane units (in other words, the monovalent organic groups contained in the M, D, and T siloxane units are epoxy group-containing hydrocarbon groups). If the silicone resin is a DQ silicone resin, the D siloxane units have an epoxy group-containing hydrocarbon group. If the silicone resin is a TQ silicone resin, the T siloxane units may have an epoxy group-containing hydrocarbon group, and if the silicone resin is a DTQ silicone resin, the D or T siloxane units may have an epoxy group-containing hydrocarbon group.

In this embodiment, the epoxy group-containing organic group is not particularly limited, and examples include epoxy groups, glycidyl ether groups, glycidyl ester groups, glycidylamino groups, and groups in which these groups are bonded to a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. More specifically, epoxy group-containing organic groups include 3-glycidoxypropyl groups, 3-glycidoxyoctyl groups, and alicyclic epoxy groups such as 2-(3,4-epoxycyclohexyl)ethyl groups.

In this embodiment, the epoxy group-containing organic group may be, in addition to the above examples, an epoxy group-containing organic group represented by the following general formula (3) or (4): In general formulas (3) and (4), "*" represents a bond to a silicon atom.
In the formula, L ^a1 is
a substituted or unsubstituted, cyclic or acyclic, saturated or unsaturated alkylene group having 2 to 22 carbon atoms;
a substituted or unsubstituted arylene group having 6 to 22 carbon atoms (including a phenylene group, an aralkyl group, etc.);
a substituted or unsubstituted, cyclic or acyclic, saturated or unsaturated divalent organic group having 2 to 22 carbon atoms and containing at least one of an oxygen atom, a nitrogen atom, or a sulfur atom;
a divalent organic group represented by -L ^a11 -X ^a11 -L ^a11 -*;
a divalent organic group represented by -L ^a11 -X ^a11 -C(═O)-L ^a11 -*;
a divalent organic group represented by -L ^a11 -X ^a11 -L ^a11 -X ^a11 -C(═O)-L ^a11 -*; or a divalent organic group represented by -L ^a11 -X ^a11 -C(═O)-X ^a11 -L ^a11 -*;
a divalent organic group represented by -L ^a11 -X ^a11 -C(═O)-L ^a11 -X ^a11 -L ^a11 -*;
(wherein X ^a11 is L ^a11 , an oxygen atom, a sulfur atom, or a divalent amino group (—NH—), L ^a11 is an alkylene group having 0 to 22 carbon atoms, or an arylene group (including a phenylene group) having 0 to 22 carbon atoms, and when there are a plurality of X ^a11 or L ^a11 in the formula, they may be the same or different from each other).
L ^a2 represents a hydrogen atom or a methyl group.

In this embodiment, the epoxy equivalent of the silicone resin-coated silicone elastomer particles is not particularly limited, but from the standpoint of compatibility and adhesion with the material to which they are added, the epoxy equivalent of the particle surface is preferably 1,000 to 100,000 g/mol, and more preferably 2,000 to 50,000 g/mol. The epoxy equivalent is determined using potentiometric titration.

In this embodiment, the silicone resin coating preferably contains a DQ silicone resin consisting of D siloxane units represented by R ¹ ₂ SiO _2/2 (R ¹ is independently an alkyl group of 1 to 20 carbon atoms, an aryl group of 6 to 20 carbon atoms, an alkyl group of 1 to 20 carbon atoms having an epoxy group, or an aryl group of 6 to 20 carbon atoms having an epoxy group) and Q siloxane units represented by SiO _4/2 , and/or a DTQ silicone resin consisting of D siloxane units represented by R ¹ ₂ SiO _2/2 (R ¹ is independently an alkyl group of 1 to 20 carbon atoms, an aryl group of 6 to 20 carbon atoms, an alkyl group of 1 to 20 carbon atoms having an epoxy group, or an aryl group of 6 to 20 carbon atoms having an epoxy group), T siloxane units represented by R ¹ ₃ SiO _1/2 (R ¹ is the same as above), and Q siloxane units represented by SiO _4/2 .
More preferably, the silicone resin coating contains a DQ silicone resin consisting of D siloxane units represented by R ¹ ₂ SiO _2/2 (wherein R ¹ is independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms and an epoxy group, or an aryl group having 6 to 20 carbon atoms and an epoxy group) and Q siloxane units represented by SiO _4/2 .

The DQ silicone resin preferably has a molar ratio of D siloxane units to Q siloxane units in the range of 8:2 to 0.8:9.2, and more preferably has a molar ratio of D siloxane units to Q siloxane units in the range of 7:3 to 5:5.
Furthermore, in the DTQ silicone resin, the ratio of the amount of D siloxane units to the total amount of T siloxane units and Q siloxane units is more preferably within the range of 8:2 to 0.8:9.2, and even more preferably within the range of 7:3 to 5:5.
In the D siloxane unit represented by R ¹ ₂ SiO _2/2 , when one R ¹ is an alkyl group or aryl group having an epoxy group, it is more preferable that the other R ¹ is an alkyl group or aryl group not having an epoxy group. In the T siloxane unit represented by ^{R 1} ₃ SiO _2/2 , when one R ¹ is an alkyl group or aryl group having an epoxy group, it is more preferable that the other R ¹ is an alkyl group or aryl group not having an epoxy group.
The D siloxane units that make up the silicone resin form two siloxane bonds, forming linear siloxane bonds, while the Q siloxane units form four siloxane bonds, forming a highly branched network or reticulated siloxane bonds. Therefore, when the amount of D siloxane units is within the above range, the silicone resin contains a large amount of moderately flexible polydiorganosiloxane structures, which improves the smoothness, flexibility, and conformability of the silicone resin coating on the surface of the silicone elastomer particles and is particularly effective in suppressing the formation of secondary aggregate particles.

The above silicone resins can be obtained by subjecting silane compounds that provide these siloxane units to a hydrolysis reaction or a dehydration/dealcoholization condensation reaction on the surface of silicone elastomer particles.

More specifically, the silicone resin can be obtained by condensing one or a mixture of two or more hydrolyzable silanes selected from a hydrolyzable silane represented by R ₂ Si(OA) ₂ (wherein R is independently a monovalent organic group and A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group) or a condensation product thereof, a hydrolyzable silane represented by RSi(OA) ₃ (wherein R is independently a monovalent organic group and A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group) or a condensation product thereof, and a hydrolyzable silane represented by Si(OA) ₄ (wherein A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group) or a condensation product thereof. Here, the condensation product of the silane compound used for coating is preferably an oligomer or a mixture of oligomers having an average of 2-20, 2-10, or 2-8, and may be, for example, tetraethoxysilane or its condensation product, ethyl silicate, or a mixture thereof.

In the formula, R represents a monovalent organic group, and examples thereof include alkyl groups such as methyl, ethyl, propyl, and butyl; cycloalkyl groups such as cyclopentyl and cyclohexyl; alkenyl groups such as vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, and decenyl; aryl groups such as phenyl, tolyl, and xylyl; aralkyl groups such as benzyl, phenethyl, and 3-phenylpropyl; halogenated alkyl groups such as 3-chloropropyl and 3,3,3-trifluoropropyl; and monovalent hydrocarbon groups such as acryloxy, methacryloxy, epoxy, glycidyl ether, glycidyl ester, and glycidylamino groups, as well as groups formed by bonding these groups to a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Industrially, it is preferable to use hydrolyzable silanes in which R represents a methyl or phenyl group. In the hydrolyzable silane, all of the R groups may be methyl groups, but they may each be a different substituent.
The silicone resin may contain the monovalent organic groups exemplified above in the siloxane unit.

In the formula, "OA" represents a hydrolyzable hydroxyl group, alkoxy group, or phenoxy group, and each A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group. From the standpoint of condensation reactivity to yield a silicone resin, OA is preferably a hydroxyl group, or an alkoxy group having 1 to 4 carbon atoms, such as a methoxy group, ethoxy group, propoxy group, or butoxy group, and in the above hydrolyzable silane, it is particularly preferred that OA is an alkoxy group having 1 to 4 carbon atoms.

The silicone resin coating in this embodiment preferably contains a silicone resin composed of a condensation reaction product of one or a combination of two or more hydrolyzable silanes selected from triorganoalkoxysilanes, diorganodialkoxysilanes, organotrialkoxysilanes, and tetraalkoxysilanes (excluding condensation reaction products of tetraalkoxysilanes alone). Furthermore, when the condensation reaction product contains any of triorganoalkoxysilanes, diorganodialkoxysilanes, and organotrialkoxysilanes, at least a portion of the silanes contained in the triorganoalkoxysilanes, diorganodialkoxysilanes, and organotrialkoxysilanes has an epoxy group-containing hydrocarbon group.
Furthermore, the silicone resin coating in this embodiment preferably includes a DQ silicone resin composed of a condensation product of a diorganodialkoxysilane and a tetraalkoxysilane, wherein at least a portion of the silane in the diorganodialkoxysilane has an epoxy group-containing hydrocarbon group. In particular, some or all of the tetraalkoxysilane may be a condensation product (oligomer/oligomer mixture), or the condensation product forming the DQ silicone resin may be a condensation product of a combination of some or all of the condensation product (oligomer/oligomer mixture) of the tetraalkoxysilane and a diorganodialkoxysilane. In this case, the molar ratio of D units derived from the diorganodialkoxysilane to Q units derived from the tetraalkoxysilane is preferably within the range of 8:2 to 0.8:9.2, and particularly preferably within the range of 7:3 to 5:5. A particularly preferred example is a DQ silicone resin that is a condensation product of dimethyldimethoxysilane and tetraethoxysilane.

The coating of the silicone elastomer particle surface using the condensation reaction product of a hydrolyzable silane is not particularly limited, but may be achieved by hydrolyzing and condensing the hydrolyzable silane in water in the presence of the silicone elastomer particles and an alkaline substance, thereby coating the surfaces of the silicone elastomer particles with a silicone resin. The timing of adding the alkaline or acidic substance is arbitrary, but from the standpoint of uniformly coating the surfaces of the silicone elastomer particles, it is preferable to emulsify the crosslinkable reactive silicone raw material and hydrolyzable silane that form the silicone elastomer particles in water to form an emulsion, and then add the alkaline substance to the emulsion after or during the hydrosilylation reaction of the crosslinkable reactive silicone.

Preferably, the hydrolyzable silane is added to the cross-linkable reactive silicone raw material that forms the silicone elastomer particles, and is emulsified in water while being uniformly mixed using a conventional agitator such as a propeller blade or flat blade.

In the above-mentioned emulsified state, from the standpoint of uniformly coating the surfaces of the silicone elastomer particles, the temperature of the aqueous reaction liquid containing the silicone elastomer particles and alkaline substance is preferably 5 to 60°C, and more preferably in the range of 10 to 60°C. Within this temperature range, the hydrolysis and condensation reaction of the hydrolyzable silane proceeds gently on the surfaces of the silicone elastomer particles, resulting in a uniform coating with silicone resin. The reaction liquid is continued to be stirred until the desired coating reaction with silicone resin is completed, and may be stirred at a temperature higher than the above temperature (for example, heated to 40°C or higher) to complete the reaction.

The alkaline or acidic substance acts as a catalyst for the hydrolysis and condensation reaction of the hydrolyzable silane. In this embodiment, alkaline substances are preferred, and they may be used alone or in combination of two or more. The alkaline substance may be added as is or as an alkaline aqueous solution. The amount of alkaline substance added is such that, for an aqueous reaction liquid containing silicone elastomer particles and an alkaline substance, the pH of the aqueous dispersion containing the alkaline substance falls within the range of 10.0 to 13.0, preferably 10.5 to 12.5. If the pH is outside this range, the silicone elastomer particles may not be sufficiently coated with the silicone resin composed of the M, D, T, and Q siloxane units derived from each hydrolyzable silane.

The alkaline substance is not particularly limited, and examples that can be used include alkali metal hydroxides such as potassium hydroxide, sodium hydroxide, and lithium hydroxide; alkaline earth metal hydroxides such as calcium hydroxide and barium hydroxide; alkali metal carbonates such as potassium carbonate and sodium carbonate; ammonia; tetraalkylammonium hydroxides such as tetramethylammonium hydroxide and tetraethylammonium hydroxide; and amines such as monomethylamine, monoethylamine, monopropylamine, monobutylamine, monopentylamine, dimethylamine, diethylamine, trimethylamine, triethanolamine, and ethylenediamine. Of these, ammonia is the most suitable, as it can be easily removed from the resulting silicone microparticle powder by volatilization. Commercially available aqueous ammonia solutions can be used as the ammonia.

After the hydrolysis and condensation reaction, the resulting silicone resin-coated silicone elastomer particles of this embodiment may be used as an aqueous dispersion (aqueous suspension) as is, but preferably the silicone resin-coated silicone elastomer particles are isolated by removing water from the reaction solution. Methods for removing water from the aqueous dispersion include, for example, drying using a vacuum dryer, a hot air circulation oven, or a spray dryer. As a pretreatment for this operation, the dispersion may be concentrated by methods such as thermal dehydration, filtration, centrifugation, and decantation, and the dispersion may be washed with water if necessary.

In the silicone resin-coated silicone elastomer particles of this embodiment, the amount of silicone resin coating is not particularly limited. The amount of silicone resin coating is preferably in the range of 5.0 to 40.0 parts by mass, and more preferably in the range of 5.0 to 30.0 parts by mass, per 100 parts by mass of the silicone elastomer particles. By ensuring that the coating amount is equal to or greater than the above-mentioned lower limit, the silicone elastomer particles can be effectively coated with the silicone resin coating, effectively achieving technical effects such as uniform dispersibility in materials such as organic resins. Furthermore, if the coating amount is too large, the hard physical properties, particularly those derived from the Q siloxane units represented by SiO _4/2 and the T siloxane units represented by RSiO _3/2 in the silicone resin, may be strongly reflected, potentially impairing the elasticity and elastic properties derived from the silicone elastomer particles. Furthermore, the coated powder may aggregate during production, easily forming coarse aggregates. However, by keeping the coating amount below the upper limit, the elasticity and elastic properties inherent in the silicone elastomer particles are fully maintained, and technical effects such as stress relaxation when blended with materials such as organic resins can be effectively achieved.
Furthermore, in this embodiment, the mass of the T siloxane units contained in the silicone resin coating layer is arbitrary, but it is preferable that both T siloxane units and Q siloxane units are contained, and that the mass of the T siloxane units does not exceed the mass of the Q siloxane units, and it is particularly preferable that the mass ratio of the T siloxane units to the Q siloxane units is in the range of 4:6 to 0:10. When the mass ratio of the T siloxane units to the Q siloxane units is in the above range, aggregation and gelation can be suppressed. Furthermore, when the silicone resin coating layer is substantially free of T siloxane units and contains only Q siloxane units (the content of the T siloxane units is generally in the range of 0.0 to 0.5 mass%), aggregation and gelation are most preferably suppressed.

The amount of silicone resin coating can be easily controlled by controlling the amount of hydrolyzable silane that forms the silicone resin added to the crosslinkable composition for forming silicone elastomer particles.

[Coating State of Silicone Elastomer Particles with Silicone Resin]
By employing the preferred manufacturing process described in the next section, the silicone resin-coated silicone elastomer particles according to this embodiment can be uniformly and smoothly coated with a silicone resin coating in which epoxy groups are dispersed on the surface, and can achieve a coating state with extremely few protrusions or irregularities on the silicone resin surface. In particular, when spherical silicone elastomer particles are uniformly coated with a silicone resin coating, the smooth particle surface suppresses secondary aggregation between particles, suppressing an increase in secondary particle size, while also reducing the occurrence of surface friction, thereby achieving stress relaxation properties and lubricity.
In this embodiment, the silicone resin coating may cover only a portion of the surface of the silicone elastomer particle, but it is preferable that the entire surface be covered. "Coating a portion of the surface of the silicone elastomer particle" means that there may be exposed portions of the silicone elastomer particle that are not covered with the silicone resin coating.

[Formation of silicone resin-coated silicone elastomer particles]
The method for producing silicone resin-coated silicone elastomer particles according to this embodiment includes the steps of:
Step (I):
(a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule;
(b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule, and (d) a silane-based compound;
emulsifying the mixture in water;
Step (II):
(c) curing the emulsion obtained in step (I) in the presence of a hydrosilylation reaction catalyst to obtain silicone elastomer particles; and
Step (III):
a step of coating a part or all of the surfaces of the silicone elastomer particles with the (d) silane-based compound and, optionally, the (e) silane-based compound-containing silicone resin added during the step (III), simultaneously with or after the step (II);
Including,
When the (e) silane-based compound is added, at least one of the (d) silane-based compound and the (e) silane-based compound contains a hydrolyzable silane having an epoxy group-containing hydrocarbon group or a condensation reaction product thereof (a silane-based compound having an epoxy group-containing hydrocarbon group),
When the (e) silane compound is not added, the (d) silane compound includes a hydrolyzable silane having an epoxy group-containing hydrocarbon group or a condensation reaction product thereof.
This manufacturing method makes it possible to suitably manufacture the silicone resin-coated silicone elastomer particles according to the present embodiment.

The above components (a), (b), and (c) can be the same as the above components. Furthermore, when components (d) and (e) contain a hydrolyzable silane, the hydrolyzable silane can be the same as the above components.

More specifically, in step (I) of the manufacturing method of this embodiment, a crosslinkable composition for forming silicone elastomer particles, including components (a) and (b), and a mixture containing component (d) a silane-based compound, are emulsified in an aqueous surfactant solution. The particle size can be easily adjusted by adjusting the emulsion particle size. Examples of surfactants include nonionic, anionic, cationic, and betaine surfactants. However, for the purpose of improving electrical reliability, it is possible and sometimes preferable to emulsify using only a nonionic surfactant without using an ionic surfactant. The particle size of the resulting silicone elastomer particles varies depending on the type and content of the surfactant. To prepare silicone elastomer particles with a small particle size, the amount of surfactant added is preferably within a range of 0.5 to 50 parts by mass per 100 parts by mass of the crosslinkable composition. On the other hand, to prepare silicone elastomer particles with a large particle size, the amount of surfactant added is preferably within a range of 0.1 to 10 parts by mass per 100 parts by mass of the crosslinkable composition. The amount of water added as a dispersion medium is preferably within a range of 20 to 1,500 parts by mass, and more preferably 50 to 1,000 parts by mass, per 100 parts by mass of the crosslinkable composition.
Furthermore, it is preferable that the component (d) silane compound contains a hydrolyzable silane or a condensation product thereof.

It is preferable to use an emulsifier to uniformly disperse the above-mentioned crosslinkable composition for forming silicone elastomer particles and silane compound in water. Examples of such emulsifiers include a homomixer, paddle mixer, Henschel mixer, homodisper, colloid mill, propeller agitator, homogenizer, in-line continuous emulsifier, ultrasonic emulsifier, and vacuum kneader.

In step (II), the emulsion obtained in step (I) is cured in the presence of a hydrosilylation reaction catalyst (c) to obtain silicone elastomer particles. Specifically, the aqueous dispersion of the crosslinkable composition for forming silicone elastomer particles containing a silane compound, prepared by the above method, is heated or left at room temperature to cure the crosslinkable silicone elastomer composition in the aqueous dispersion, thereby producing an aqueous dispersion of silicone elastomer particles. When the aqueous dispersion of silicone elastomer particles is heated, the heating temperature is preferably 100°C or less, and more preferably 10 to 95°C. Methods for heating the aqueous dispersion of the crosslinkable silicone elastomer composition include, for example, directly heating the aqueous dispersion and adding the aqueous dispersion to hot water.

In step (III), simultaneously with or after step (II), part or all of the surface of the silicone elastomer particles is coated with a silicone resin containing (d) a silane compound and, optionally, (e) a silane compound added during step (III). Specifically, simultaneously with the formation of the aqueous dispersion of the silicone elastomer particles (simultaneously with step (II)), or after the formation of the aqueous dispersion of the silicone elastomer particles (after step (II)), the surfaces of the silicone elastomer particles can be coated with the silicone resin through a hydrolysis condensation reaction of the silane compound contained in the aqueous dispersion. The conditions for coating with the silicone resin are as described above.

In step (III), the silane-based compound contained in the aqueous dispersion may be all present in the system in the step of emulsifying in water (step (I)), or may be present in the system in multiple steps (steps (I) and (III)). In other words, the silane-based compound contained in the aqueous dispersion may be a silane derived from the silane-based compound (d) in the mixture of step (I), and may further contain the silane-based compound (e) added in step (III).
By adding the silane compound in multiple batches in this manner, the silanols contained in the silane compound added and reacted in the previous stage are more likely to be uniformly present on the particle surface, which allows the silane compound present earlier to react efficiently with the silane compound added later, suppressing aggregation and increasing the amount of functional groups introduced.
When the silane compound is added in multiple portions in this manner, the temperature at which the subsequent silane compound is added is preferably 5 to 15°C, and from the viewpoint of effectively completing the condensation reaction after the addition of the silane compound, the reaction is preferably carried out at 50 to 75°C.
When a silane compound (e) is added in step (III), it is preferable that the silane compound (e) contains a hydrolyzable silane.

The silicone resin-coated silicone elastomer particles produced contain epoxy groups. In this embodiment, the manufacturing method includes a silane compound having an epoxy group-containing hydrocarbon group (hereinafter also referred to as epoxy group-containing silane) as part of the silane compounds contained in the aqueous dispersion. The epoxy group-containing silane may be present in its entirety in the stage of emulsification in water (step (I)), or it may be present in the system when the silicone elastomer particle surfaces are coated with the silicone resin (step (III)). Alternatively, it may be present in the system in multiple stages (steps (I) and (III)). In other words, when the (e) silane compound is added in step (III), at least one of the (d) silane compound and the (e) silane compound contains an epoxy group-containing carbon silane. Furthermore, when the (e) silane compound is not added, the (d) silane compound contains an epoxy group-containing silane.

In step (III), part or all of the surface of the silicone elastomer particles is coated with a silicone resin containing a silane compound. The "silane compound" includes not only hydrolyzable silanes (organotrialkoxysilanes, diorganodialkoxysilanes, triorganoalkoxysilanes, tetraalkoxysilanes, etc.), but also compounds that form M siloxane units, D siloxane units, T siloxane units, and Q siloxane units within the silicone resin, such as oligomers (e.g., tetra-pentamers) formed by the condensation of multiple hydrolyzable silane molecules. Examples of silane compounds other than hydrolyzable silanes include oligomers formed by the condensation of multiple molecules of tetraalkoxysilane, etc. The oligomer is preferably an oligomer or oligomer mixture having an average of 2-20, 2-10, or 2-8. For example, tetraethoxysilane or its condensation product, ethyl silicate, or a mixture thereof, may be used.

Furthermore, from the viewpoint of obtaining a silicone resin containing a DQ silicone resin having an epoxy group, it is preferable to use the following silanes as the respective silane-based compounds.
(d) The silane compound preferably includes a tetraalkoxysilane or a condensation product thereof (e.g., methyl silicate or ethyl silicate), and the epoxy group-containing silane preferably includes a diorganodialkoxysilane having an epoxy group-containing hydrocarbon group or a condensation product thereof (in other words, it is preferable to have at least a tetraalkoxysilane or a condensation product thereof present in the step of emulsifying in water (step (I)), and it is preferable to use at least a diorganodialkoxysilane having an epoxy group-containing hydrocarbon group or a condensation product thereof as the epoxidation component). The epoxy group-containing silane may be a diorganodialkoxysilane having an epoxy group-containing hydrocarbon group, a condensation product thereof, or a mixture thereof.
In this case, the (d) silane compound may further contain a diorganodialkoxysilane or a condensation product thereof (in other words, in the step of emulsifying in water (step (I)), not only a tetraalkoxysilane or a condensation product thereof but also at least a diorganodialkoxysilane or a condensation product thereof may be present.) In this way, excess silanol generated from the hydrolyzable silane of the Q siloxane unit reacts with the D siloxane unit, thereby reducing the amount of residual silanol groups and reducing aggregation.

By coating with the above-mentioned silicone resin, an aqueous dispersion of silicone resin-coated silicone elastomer particles can be obtained. This aqueous dispersion is stable at room temperature and can be used as is as a cosmetic ingredient or as an additive for water-based paints or coatings.

Furthermore, silicone resin-coated silicone elastomer particles can be prepared by removing water from an aqueous dispersion of silicone resin-coated silicone elastomer particles. Methods for removing water from the aqueous dispersion include, for example, drying using a vacuum dryer, a hot air circulation oven, or a spray dryer. The heating and drying temperature of the spray dryer must be appropriately set based on the heat resistance and crosslinking temperature of the silicone resin-coated silicone elastomer particles. To prevent secondary aggregation of the resulting microparticles, it is preferable to control the temperature of the silicone resin-coated silicone elastomer particles below the glass transition temperature of the silicone resin coating their surfaces. The silicone elastomer particles obtained in this manner can be recovered using a cyclone, bag filter, or the like.

[Crushing/classifying operation]
The silicone resin-coated silicone elastomer particles of this embodiment are obtained by the above-mentioned method, but if the silicone resin-coated silicone elastomer particles obtained by removing moisture or the like are aggregated, they can be mechanically disintegrated using a crusher such as a jet mill, a ball mill, or a hammer mill, and this is preferable.Furthermore, they can be classified using a sieve or an airflow classifier so as to have a specific particle size or less.In particular, by mechanically disintegrating the silicone resin-coated silicone elastomer particles containing aggregates before use, uniform functional particles can be obtained that do not contain coarse particles, and the dispersibility in materials such as various organic resins, stress relaxation properties, etc. can be improved.

[Average primary particle diameter]
The silicone resin-coated silicone elastomer particles of this embodiment are not particularly limited in terms of their average primary particle diameter, but the average primary particle diameter measured by laser diffraction scattering is preferably 0.1 to 100 μm, more preferably 0.1 to 50 μm, even more preferably 0.2 to 30 μm, and most preferably 0.5 to 10 μm. The particle diameter of the silicone resin-coated silicone elastomer particles is controlled depending on the silicone elastomer particles before coating, the coating amount, and the above-mentioned crushing/classification process. By having an average primary particle diameter that is equal to or less than the above upper limit, for example, when the silicone resin-coated silicone elastomer particles of this embodiment are added to a resin for producing a thin film layer, the particle diameter can be adjusted to correspond to the thickness of the thin film layer.

[Advantages of manufacturing silicone resin-coated silicone elastomer particles]
When the silicone resin-coated silicone elastomer particles of this embodiment are obtained by the above-mentioned manufacturing method, the surface of the silicone elastomer particles is uniformly and smoothly coated with the silicone resin, secondary aggregation of the silicone resin-coated silicone elastomer particles is effectively suppressed, and handling problems such as an increase in aggregate particle size over time are unlikely to occur. Furthermore, this manufacturing method may also be carried out by emulsifying a mixture containing a crosslinkable composition for forming silicone elastomer particles and a hydrolyzable silane to form an aqueous dispersion, and the curing reaction and surface coating with the silicone resin may be carried out in the same container (i.e., one pod).

[Additives for organic resins, organic resins, paints, and coating agents]
The silicone resin-coated silicone elastomer particles of the present embodiment described above are excellent in uniform dispersibility in a wide range of materials to which they are added, such as paints, coating agents, and organic resins (thermosetting organic resins and thermoplastic organic resins), and, if desired, in stress relaxation properties, etc., and are also highly easy to handle and work with, as they are less likely to scatter or adhere to containers during blending.Furthermore, members, paint films, or coating films obtained by curing organic resins blended with these silicone resin-coated silicone elastomer particles have improved flexibility (including the softness of the coating layer), durability, and adhesion and conformability to substrates, and are particularly excellent in flexibility and thermal shock resistance, making them extremely useful as high-performance organic resins, paints, or coating agents for use in electronic materials.
Thus, although not particularly limited, examples of the present embodiment may include: an additive for organic resins comprising the silicone resin-coated silicone elastomer particles of the present embodiment; an organic resin composition comprising the silicone resin-coated silicone elastomer particles of the present embodiment; a curable organic resin composition comprising the silicone resin-coated silicone elastomer particles of the present embodiment and a curable organic resin; and a paint or coating agent comprising the silicone resin-coated silicone elastomer particles of the present embodiment.
In the organic resin additive of this embodiment, the organic resin may contain an epoxy resin. In the paint or coating agent of this embodiment, the organic resin may contain an epoxy resin. In the curable organic resin composition of this embodiment, the curable organic resin may contain an epoxy resin.
Furthermore, the present embodiment can also provide a cured product obtained by curing the curable organic resin composition of the present embodiment; a semiconductor device including the cured product of the present embodiment; and a method for manufacturing a semiconductor device, which includes curing the curable organic resin composition of the present embodiment.
The silicone resin-coated silicone elastomer particles according to this embodiment may be used in combination with a solid (particularly powder-like) or liquid (particularly modified silicone materials such as oil) additive for organic resins.

The additive for organic resins, organic resin composition, curable organic resin composition, paint or coating agent, cured product, semiconductor device, and method for manufacturing a semiconductor device according to this embodiment will be described in more detail below.

[Organic resin]
In this embodiment, suitable examples of the organic resin include curable organic resins and thermoplastic organic resins. Of these, curable organic resins are suitable for electronic materials such as semiconductor substrates. More specifically, examples of the curable organic resin include phenolic resins, formaldehyde resins, xylene resins, xylene-formaldehyde resins, ketone-formaldehyde resins, furan resins, urea resins, imide resins, melamine resins, alkyd resins, unsaturated polyester resins, aniline resins, sulfone-amide resins, silicone resins, epoxy resins, bismaleimide triazine resins, thermosetting polyphenylene ether resins, maleimide resins, and copolymer resins of these resins. Two or more of these curable organic resins can also be combined. In particular, the curable resin is preferably at least one selected from the group consisting of epoxy resins, phenolic resins, imide resins, and silicone resins. The epoxy resin may be any compound containing a glycidyl group or an alicyclic epoxy group, and examples thereof include o-cresol novolac type epoxy resins, phenol novolac type epoxy resins, biphenyl type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, dicyclopentadiene type epoxy resins, naphthalene type epoxy resins, anthracene type epoxy resins, naphthol aralkyl type epoxy resins, polyvinylphenol type epoxy resins, diphenylmethane type epoxy resins, diphenylsulfone type epoxy resins, triphenolalkane type epoxy resins, cresol-naphthol co-condensation type epoxy resins, bisphenylethylene type epoxy resins, fluorene type epoxy resins, stilbene type epoxy resins, spirocoumarone type epoxy resins, norbornene type epoxy resins, terpene type epoxy resins, phenolcyclohexane type epoxy resins, halogenated epoxy resins, imide group-containing epoxy resins, maleimide group-containing epoxy resins, allyl group-modified epoxy resins, and silicone-modified epoxy resins. Examples of the phenolic resin include polyvinylphenol, phenol novolac, naphthol, terpene, phenol dicyclopentadiene, phenol aralkyl, naphthol aralkyl, triphenol alkane, dicyclopentadiene, cresol-naphthol co-condensation, and xylene-naphthol co-condensation. Examples of silicone resins include epoxy-modified silicone resins obtained by reacting an epoxy resin with a silanol group or a silicon-bonded alkoxy group in the silicone resin. Examples of the curing mechanism of such curable organic resins include heat curing, high-energy ray curing such as ultraviolet light or radiation, moisture curing, condensation reaction curing, and addition reaction curing. The state of such curable organic resins at 25°C is not limited, and they may be either liquid or solid that softens upon heating.

In this embodiment, the organic resin composition containing the organic resin may contain other optional components such as a curing agent, curing accelerator, filler, photosensitizer, higher fatty acid metal salt, ester wax, plasticizer, etc. Examples of the curing agent include organic acids such as carboxylic acids and sulfonic acids and their anhydrides; organic hydroxy compounds; organosilicon compounds having silanol groups, alkoxy groups, or halogeno groups; and primary or secondary amino compounds, and combinations of two or more of these are also possible. Examples of the curing accelerator include tertiary amine compounds, organometallic compounds such as aluminum and zirconium; organophosphorus compounds such as phosphines; heterocyclic amine compounds, boron complex compounds, organic ammonium salts, organic sulfonium salts, organic peroxides, and hydrosilylation catalysts. Examples of fillers include fibrous fillers such as glass fiber, asbestos, alumina fiber, ceramic fiber containing alumina and silica, boron fiber, zirconia fiber, silicon carbide fiber, metal fiber, polyester fiber, aramid fiber, nylon fiber, phenolic fiber, and natural animal and plant fibers; and particulate fillers such as fused silica, precipitated silica, fumed silica, calcined silica, zinc oxide, calcined clay, carbon black, glass beads, alumina, talc, calcium carbonate, clay, aluminum hydroxide, barium sulfate, titanium dioxide, aluminum nitride, silicon carbide, magnesium oxide, beryllium oxide, kaolin, mica, and zirconia, and combinations of two or more of these are also possible. In the case of epoxy resins, it is particularly preferable to include an amine-based curing agent.

The silicone resin-coated silicone elastomer particles of this embodiment may be blended as an additive with thermoplastic organic resins other than those mentioned above, and can be used as a physical property modifier such as a surface lubricant or stress relief agent, or as an optical property modifier such as a light scattering agent. The type of thermoplastic organic resin is not particularly limited, and may be at least one polymer selected from the group consisting of polycarbonate-based resins, polyester-based resins, polyether-based resins, polylactic acid-based resins, polyolefin-based resins such as polyethylene, polypropylene, and ethylene-propylene copolymers, polystyrene-based resins, styrene-based copolymers, fluorine-based polymers such as tetrafluoroethylene, polyvinyl ethers, and cellulose-based polymers, or a composite resin composed of a combination thereof. The silicone resin-coated silicone elastomer particles of this embodiment can be uniformly dispersed in these thermoplastic organic resins (including masterbatches) using a mixing device such as a twin-screw or single-screw extruder or kneader/mixer, and may be molded into a desired shape, such as a film, for use.

The amount of silicone resin-coated silicone elastomer particles added in this embodiment can be selected appropriately depending on the physical properties required of the organic resin, but is generally in the range of 0.1 to 30 parts by mass, and may be in the range of 0.5 to 10 parts by mass, per 100 parts by mass of organic resin. If the amount of the particles added is less than the lower limit, performance such as stress relaxation properties for the resin may be insufficient, and the flexibility and thermal shock resistance of the resulting cured organic resin may decrease, particularly the thermal shock resistance after moisture absorption. On the other hand, if the amount exceeds the upper limit, the organic resin, paint, or coating agent may thicken after blending, reducing handling and workability, and the mechanical properties of the resulting cured organic resin may tend to decrease.

In one embodiment of the organic resin composition, curable organic resin composition, and cured product of this embodiment, the silicone resin-coated silicone elastomer particles may be free of ionic surfactants. Specifically, in the composition of this embodiment, the content of ionic surfactant may be less than 0.5 mass%, less than 0.1 mass%, less than 0.05 mass%, less than 0.01 mass%, or less than 0.001 mass%, based on 100 mass% of the total solids content of the composition. When the organic resin composition, curable resin composition (particularly, epoxy resin composition), and cured product of this embodiment are used in semiconductor applications, for example, if the content of ionic surfactant is less than the lower limit, they can be particularly suitable for use in electronic materials. This is because a decrease in electrical reliability due to ionic components in the surfactant can be prevented.
Such surfactants are not particularly limited and include ionic surfactants and nonionic surfactants. Ionic surfactants also include anionic surfactants, cationic surfactants, and amphoteric surfactants. More specific examples of these surfactants include those described in JP 2013-035758 A. The silicone resin-coated silicone elastomer particles of this embodiment can be designed to be free of ionic surfactants, and as described below, are particularly suitable for use as sealants in the manufacture of semiconductor devices. The type and amount of ionic surfactant in the particles can be identified by known techniques such as high-performance liquid chromatography.

Furthermore, the organic resin composition and curable organic resin composition of the present embodiment may be free of a volatile solvent, depending on the optional selection and application. Specifically, in the organic resin composition and curable organic resin composition of the present embodiment, the content of the volatile solvent may be less than 0.5 mass%, less than 0.1 mass%, less than 0.05 mass%, less than 0.01 mass%, or less than 0.001 mass%, relative to 100 mass% of the total solid content of the composition.
Such volatile solvents are not particularly limited and include, for example, organic solvents such as alcohols such as methanol and ethanol; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; esters such as ethyl acetate, butyl acetate, and cellosolve acetate; amides such as N,N-dimethylformamide; olefins such as hexane, heptane, and octane; and aromatic hydrocarbons such as toluene and xylene. The composition of the present embodiment may be particularly suitable for use as a sealant or the like in the manufacture of semiconductor devices by being designed so as not to contain these volatile solvents depending on the application.

The organic resin composition containing the organic resin according to this embodiment is preferably an epoxy resin composition, and may contain, in addition to the silicone resin-coated silicone elastomer particles, which are component (A), the following epoxy resin (B) (hereinafter also referred to as "component (B)"), curing agent (C) (hereinafter also referred to as "component (C)"), and filler (D) (hereinafter also referred to as "component (D)"). Furthermore, in one aspect, the organic resin composition according to this embodiment may contain additives other than these components, as long as they do not interfere with the effects of the present invention.

<Component (B): Epoxy Resin>
The composition of one aspect of this embodiment includes an epoxy resin (B). The epoxy resin (B) is a curable resin having an epoxy group, and specific examples thereof include bixylenol-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, bisphenol S-type epoxy resins, bisphenol AF-type epoxy resins, dicyclopentadiene-type epoxy resins, trisphenol-type epoxy resins, naphthol novolac-type epoxy resins, phenol novolac-type epoxy resins, tert-butyl-catechol-type epoxy resins, naphthalene-type epoxy resins, naphthol-type epoxy resins, anthracene-type epoxy resins, and glycidylamine-type epoxy resins. epoxy resins, glycidyl ester type epoxy resins, cresol novolac type epoxy resins, phenol aralkyl type epoxy resins, biphenyl type epoxy resins, linear aliphatic epoxy resins, epoxy resins having a butadiene structure, alicyclic epoxy resins, heterocyclic epoxy resins, spiro ring-containing epoxy resins, cyclohexane type epoxy resins, cyclohexane dimethanol type epoxy resins, naphthylene ether type epoxy resins, trimethylol type epoxy resins, tetraphenylethane type epoxy resins, isocyanurate type epoxy resins, phenolphthalimidine type epoxy resins, etc.
The epoxy resin may be used alone or in combination of two or more kinds.

Furthermore, from the viewpoint of obtaining a cured product having excellent heat resistance, the epoxy resin (B) preferably contains an epoxy resin containing an aromatic structure. The aromatic structure is a chemical structure generally defined as aromatic, and also includes polycyclic aromatic rings and aromatic heterocycles.
Specific examples of epoxy resins containing an aromatic structure include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, bisphenol AF type epoxy resins, dicyclopentadiene type epoxy resins, trisphenol type epoxy resins, naphthol novolac type epoxy resins, phenol novolac type epoxy resins, tert-butyl-catechol type epoxy resins, naphthalene type epoxy resins, naphthol type epoxy resins, anthracene type epoxy resins, bisphenol S type epoxy resins, and glycidylamine type epoxy resins having an aromatic structure. resins, glycidyl ester type epoxy resins having an aromatic structure, cresol novolac type epoxy resins, biphenyl type epoxy resins, linear aliphatic epoxy resins having an aromatic structure, epoxy resins having a butadiene structure having an aromatic structure, alicyclic epoxy resins having an aromatic structure, heterocyclic epoxy resins, spiro ring-containing epoxy resins having an aromatic structure, cyclohexanedimethanol type epoxy resins having an aromatic structure, naphthylene ether type epoxy resins, trimethylol type epoxy resins having an aromatic structure, tetraphenylethane type epoxy resins having an aromatic structure, and the like.

The content of the epoxy resin (B) is, for example, 1% by mass or more, preferably 2% by mass or more, relative to 100% by mass of the total solid content of the composition, which allows the fluidity of the composition during molding to be appropriately set and improves the filling property.
The content of the epoxy resin (B) is, for example, 15% by mass or less, preferably 10% by mass or less, and more preferably 5% by mass or less, based on 100% by mass of the total solid content of the composition. The thermal expansion coefficient of the resin is usually higher than that of the filler (D) described below. Therefore, it is believed that the thermal shrinkage can be further reduced by relatively reducing the amount of the epoxy resin (B). In other words, it is believed that the warpage of the substrate can be further reduced.
The total solid content of the composition refers to the sum of all components contained in the composition of one aspect of this embodiment, excluding the solvent.

<Component (C): Curing Agent>
The composition of one aspect of this embodiment includes a curing agent (C). The curing agent (C) is not particularly limited as long as it has the property of curing the epoxy resin.
The curing agent (C) preferably includes a phenol-based curing agent, which is preferred in terms of the balance of flame resistance, moisture resistance, electrical properties, curability, storage stability, and the like.
The phenol-based curing agent includes a monomer, oligomer, polymer, etc. having two or more phenolic hydroxyl groups in the molecule. The molecular weight, molecular structure, etc. are not particularly limited.
More specifically, the phenolic curing agent includes novolac-type phenolic resins such as phenol novolac resin, cresol novolac resin, bisphenol novolac, and phenol-biphenyl novolac resin; polyvinylphenol; multifunctional phenolic resins such as trisphenylmethane-type phenolic resin; modified phenolic resins such as terpene-modified phenolic resin and dicyclopentadiene-modified phenolic resin; phenol aralkyl-type phenolic resins such as phenol aralkyl resins having a phenylene skeleton and/or biphenylene skeleton, and naphthol aralkyl resins having a phenylene and/or biphenylene skeleton; and bisphenol compounds such as bisphenol A and bisphenol F.

Examples of the curing agent (C) other than the phenol-based curing agent include amine-based curing agents, acid anhydride-based curing agents, mercaptan-based curing agents, and catalyst-type curing agents.
Specific examples of the amine-based curing agent include aliphatic polyamines and aromatic polyamines.
Specific examples of the acid anhydride curing agent include alicyclic acid anhydrides such as hexahydrophthalic anhydride (HHPA) and methyltetrahydrophthalic anhydride (MTHPA), and aromatic acid anhydrides such as trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), and benzophenonetetracarboxylic acid (BTDA).
The mercaptan-based curing agent includes polymercaptan compounds such as polysulfide, thioester, and thioether.
Specific examples of catalyst-type curing agents include tertiary amine compounds such as benzyldimethylamine (BDMA) and 2,4,6-trisdimethylaminomethylphenol; imidazole compounds such as 2-methylimidazole and 2-ethyl-4-methylimidazole; and Lewis acids such as _BF3 complex.
The curing agent (B) may be used alone or in combination of two or more.

The content of the curing agent (C) is, for example, 0.5% by mass or more, preferably 1% by mass or more, and more preferably 1.5% by mass or more, relative to 100% by mass of the total solid content of the composition, which provides excellent fluidity during molding and improves filling properties and moldability.
The content of the curing agent (C) is, for example, 9% by mass or less, preferably 8% by mass or less, and more preferably 7% by mass or less, relative to 100% by mass of the total solid content of the composition, which can contribute to further suppression of warpage of the substrate.

<Component (D): filler>
The composition of one aspect of this embodiment includes a filler (D). The filler (D) may be an inorganic filler or an organic filler. Specific examples of inorganic fillers include silica, alumina, silicon nitride, aluminum nitride, boron nitride, titanium oxide, silicon carbide, titanium white, aluminum hydroxide, magnesium hydroxide, talc, clay, mica, glass fiber, diamond, graphite, carbon nanotubes, graphene, and other carbon allotropes. Specific examples of organic fillers include styrene-type, butadiene-type, and acrylic-type rubber powders, silicone resin powders, silicone elastomer particles, silicone elastomer composite particles, silicone resin-coated silicone elastomer particles (excluding those corresponding to component (A) of the present invention), and resins such as acrylic core-shell particles. The filler (D) may be used alone or in combination of two or more types. The particle shape is preferably as spherical as possible, and the loading amount can be increased by mixing particles of different sizes. Furthermore, from the viewpoint of heat dissipation, it is also possible to replace part or all of the silica with alumina, silicon nitride, aluminum nitride, boron nitride, or the like.
Among these, the filler (D) preferably contains an inorganic filler, and more preferably contains silica. Examples of silica include fused crushed silica, fused spherical silica, crystalline silica, and secondary agglomerated silica.

As described above, the filler (D) is usually in the form of particles, and the shape of the particles may be spherical, but is not limited thereto.
The average particle size of the filler (D) is not particularly limited, but is typically 0.1 to 100 μm, 1 to 100 μm, preferably 0.5 to 50 μm, 1 to 50 μm, and more preferably 1 to 20 μm. Having an average particle size within the above range can ensure appropriate fluidity during curing. It is also possible to improve the filling ability of narrow gaps in cutting-edge wafer-level packages, for example, by making the average particle size relatively small (e.g., 1 to 20 μm) and combining particles with different average particle sizes.
The average particle size of the filler (D) can be determined by obtaining volume-based particle size distribution data using a laser diffraction/scattering particle size distribution analyzer and processing the data. The measurement is usually performed wet.

When the filler (D) is an inorganic filler such as silica, it may be surface-modified with a coupling agent such as a silane coupling agent or a titanium-based coupling agent. This suppresses aggregation of the inorganic filler, resulting in better fluidity. In addition, the affinity between the inorganic filler and other components is increased, improving the dispersibility of the inorganic filler. This is thought to contribute to improving the mechanical strength of the cured product and suppressing the occurrence of microcracks.
The coupling agent for surface modification will be explained later in the section on coupling agent (E).

The content of the filler (D) is, for example, 45% by mass or more, 55% by mass or more, preferably 70% by mass or more, and more preferably 85% by mass or more, relative to 100% by mass of the total solid content of the composition. By appropriately increasing the content of the filler (D), warpage of the chip or substrate can be further reduced. Furthermore, by appropriately increasing the content of the filler (D) and relatively reducing the resin component, thermal expansion change after the composition is cured can be reduced. A small thermal expansion change makes it easier to suppress deterioration of warpage.
The content of the filler (D) is, for example, 98% by mass or less, preferably 95% by mass or less, and more preferably 92% by mass or less, based on 100% by mass of the total solid content of the composition. By appropriately reducing the content of the filler (D), it is possible to suppress deterioration of moldability due to a decrease in fluidity during molding.

<Component (E): Coupling Agent>
The composition of one aspect of this embodiment may optionally contain a coupling agent (E) (hereinafter also referred to as "component (E)"). By including the coupling agent (E), for example, it is possible to further improve adhesion to the substrate and improve the dispersibility of the filler (D) in the composition. The improved dispersibility of the filler (D) improves the homogeneity of the final cured product, which can contribute to improving the mechanical strength of the cured product.

Examples of coupling agents (E) include known coupling agents such as epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, alkenyl silanes such as vinyl silane and hexenyl silane, various silane compounds such as acrylic silane and methacrylic silane, titanium compounds, aluminum chelates, and aluminum/zirconium compounds. Coupling agents (E) may be used alone or in combination of two or more. Known surface treatment agents such as silazanes may also be used in combination.

The content of the coupling agent (E) is, for example, 0.1% by mass or more, preferably 0.2% by mass or more, based on the total mass of the composition. The coupling agent (E) is generally used in a treatment amount ranging from 0.01 to 2% by mass, where the total mass of the filler (D) is taken as 100% by mass.
The content of the coupling agent (E) is, for example, 2.0 mass % or less, and preferably 1.0 mass % or less, based on the total mass of the composition.

<Other ingredients>
The composition of one aspect of this embodiment may contain other optional components as needed. Examples of such optional components include various additives such as pH adjusters, ion scavengers, flame retardants, colorants, release agents, stress reducing agents (excluding those corresponding to the silicone resin-coated silicone elastomer particles of one aspect of this embodiment), antioxidants, and heavy metal deactivators. Specific examples of such additives include those listed in JP 2020-023643 A (see paragraphs [0070] to [0075]), WO 2024/202136 A ([0083] to [0086]), and WO 2021/149727 A ([0090] to [0093]).
When these optional components are contained, the content of each component varies depending on the type and application, but may be within a range that does not impair the effects of the present invention, and is, for example, in the range of 0.1 to 5.0 mass%, preferably 0.1 to 3.0 mass%, and more preferably 0.2 to 1.5 mass%.

[Production method, method for forming cured product, and uses]
The composition of one aspect of this embodiment can be produced by uniformly mixing components (A) to (D) and optional components such as component (E). Mixing can be performed using appropriate equipment, such as a mixer or blender. The resulting mixture is melt-kneaded using a kneader, heated rolls, or the like, preferably at a temperature of 40°C to 130°C, and then cooled and solidified to prepare a composition of one aspect of this embodiment (specifically, a liquid, solid, or hot-melt (also known as B-stage) curable epoxy resin composition). The composition may be pulverized into powder or granules. Alternatively, the powder/granule composition may be compressed into tablets.
Furthermore, a sheet-like composition can be produced by placing the mixture of the above composition on a pallet, cooling it, and then pressing it, rolling it, or applying a mixture containing a solvent to form it into a sheet.
The composition of one aspect of this embodiment can be optionally melted by heating or the like and then cured by a known curing method depending on the type of curable resin to form a cured product of the composition of one aspect of this embodiment. For example, when the composition of one aspect of this embodiment contains an epoxy resin, it can be optionally melted by heating and then finally cured by heating. In this case, the curing reaction temperature is, for example, in the range of 100 to 300°C, preferably 150 to 250°C, more preferably 150 to 200°C, and even more preferably 170 to 180°C.
The cured product of one aspect of this embodiment has properties such as heat resistance, a low modulus of elasticity, and/or a low coefficient of thermal expansion, and therefore can be suitably used in semiconductor devices. More specifically, the cured product can be suitably used, for example, as an encapsulant for semiconductor elements, IC chips, etc., a pressure-sensitive adhesive for semiconductor devices, an adhesive, an underfill agent, an insulating material, a build-up material for package substrates, etc.
Furthermore, a comparison of the relative dielectric constants (Dk [5 to 10 GHz]) of the blank of Comparative Example 1, the silicone resin of Comparative Example 2, and the silicone elastomer particles of Comparative Example 5 in Table 1 of paragraph 0090 of JP 2023-034257 A shows that the silicone elastomer particles are also expected to have a low dielectric effect. This characteristic also makes them applicable to package substrates, etc.

[Semiconductor device and method for manufacturing the semiconductor device]
The cured product obtained by curing the curable organic resin composition of the present embodiment has a low elastic modulus and/or a low thermal expansion coefficient, and therefore can be suitably used in semiconductor devices. More specifically, the cured product can be suitably used as, for example, an encapsulant for semiconductor elements, IC chips, etc., a pressure-sensitive adhesive for semiconductor devices, an adhesive, an underfill agent, an insulating material, a build-up material for package substrates, etc.
The curable resin composition of this embodiment, particularly the curable epoxy resin composition (powder, tablet, granular, etc.), can be suitably used as a heat-melting (B-stage material) sealing material for sealing semiconductor elements. The method for sealing semiconductor elements is not particularly limited, and can be performed by known methods such as conventional transfer molding (transfer molding) and compression molding (compression molding). The semiconductor package to which the cured product of this embodiment can be applied is also not particularly limited, and can be used to seal various semiconductor packages described, for example, in JP 2020-063338 A, JP 2019-085514 A, JP 2020-023643 A, etc.

The method for manufacturing a semiconductor device of this embodiment is not particularly limited, and may include a step of curing the composition of this embodiment at any stage in the manufacturing process of the semiconductor device. The method for manufacturing a semiconductor device of this embodiment may also include a step of encapsulating a semiconductor element with a cured product of one aspect of this embodiment.

For example, after placing a laminate mounting a large number of semiconductor elements such as ICs in the cavity of a mold, the cavity is filled with the composition of one aspect of this embodiment, which is then heated and cured, thereby producing a semiconductor device in which the semiconductor elements are encapsulated with the cured product of one aspect of this embodiment.

The molding conditions can be selected appropriately depending on the molding method, the curability of the curable resin composition, the mold temperature, and other factors. As an example, the conditions for transfer molding using the curable epoxy resin composition of this embodiment can be set appropriately depending on the type of material in the composition of one aspect of this embodiment and the type of semiconductor device to be manufactured. Typically, the mold temperature is 170 to 180°C, and the molding time can be selected depending on the mold temperature and curability, but is generally set to 10 to 600 seconds, or 30 to 120 seconds. After the initial curing, post-curing or heat treatment can be performed for a period ranging from a few seconds to a few hours to complete the curing reaction.

Furthermore, a semiconductor device can be manufactured using a sheet-shaped curable organic resin composition by flip-chip mounting, for example, as follows. That is, the sheet-shaped composition is placed on the electrode side of a semiconductor element equipped with bonding bumps, or on the bump bonding side of a circuit board, and the semiconductor element and circuit board are bump-bonded and then adhesively sealed with a resin, thereby flip-chip mounting the semiconductor device.

Furthermore, since the silicone resin-coated silicone elastomer particles of this embodiment have excellent stress relaxation properties when blended with an organic resin, they may be blended with epoxy resins for printed wiring boards to form prepregs. Furthermore, copper foil with a filler particle-containing resin layer for printed wiring boards may be formed by forming a copper foil with a resin layer containing the silicone resin-coated silicone elastomer particles of this embodiment on one side of the copper foil, and this can be used for copper-clad laminate (CCL) applications. Therefore, the cured product of this embodiment may be included in copper-clad laminates as semiconductor devices.

[Paints and coatings]
In this embodiment, examples of paints and coating agents include room temperature curing types, room temperature drying types, and heat curing types, and depending on their properties, examples include water-based, oil-based, and powder-based types.Furthermore, depending on the vehicle resin, examples include polyurethane resin paint, butyral resin paint, long oil phthalic acid resin paint, alkyd resin paint, amino alkyd resin paint consisting of amino resin and alkyd resin, epoxy resin paint, acrylic resin paint, phenolic resin paint, silicone modified epoxy resin paint, silicone modified polyester resin paint, and silicone resin paint.

The amount of silicone resin-coated silicone elastomer particles added in this embodiment can be selected appropriately depending on the physical properties required of the paint or coating agent. However, in order to impart a uniform, soft matte finish to the resulting paint film, it is preferably in the range of 0.1 to 150 parts by mass, more preferably 0.1 to 100 parts by mass, and particularly preferably 0.1 to 50 parts by mass, or 0.1 to 20 parts by mass, per 100 parts by mass of the solids content of the paint. If the amount of the particles added is less than the lower limit, the matte finish, adhesion, stress relaxation properties, and other performance characteristics of the paint film may be insufficient. If the amount exceeds the upper limit, the organic resin, paint, or coating agent may thicken after blending, reducing handling and workability.

The paint and coating agent of this embodiment may contain alcohols such as methanol and ethanol; ketones such as methyl ethyl ketone and methyl isobutyl ketone; esters such as ethyl acetate, butyl acetate, and cellosolve acetate; amides such as N,N-dimethylformamide; olefins such as hexane, heptane, and octane; organic solvents such as aromatic hydrocarbons such as toluene and xylene; known inorganic fillers such as reinforcing silica, organic fillers, curing accelerators, silane coupling agents, pigments such as carbon black, dyes, antioxidants, thickeners made of polymeric compounds, flame retardants, and weather resistance agents.

[Cosmetic composition]
The silicone resin-coated silicone elastomer particles of this embodiment are also useful as cosmetic raw materials. Because they are coated with a silicone resin coating, they have superior oil absorption properties and uniform dispersibility in other cosmetic raw materials (especially oily raw materials) compared to conventionally known silicone elastomer particles and silicone composite particles. When applied to skin or hair, they suppress the oiliness and stickiness of the cosmetic, imparting a smooth spread and soft feel, and offering an excellent feel when used. Furthermore, the silicone resin-coated silicone elastomer particles of this embodiment are less likely to scatter and adhere to containers, resulting in excellent handling and formulation stability. More specifically, the silicone resin-coated silicone elastomer particles of this embodiment may be incorporated into cosmetics in the same manner as in International Patent Publication WO 2020/137913.

Although this embodiment has been described above, the silicone resin-coated silicone elastomer particles of the present invention, their manufacturing method, and additives for organic resins and other uses are not limited to the above examples, and appropriate modifications can be made to the silicone resin-coated silicone elastomer particles of the present invention, their manufacturing method, and additives for organic resins and other uses.

The silicone resin-coated silicone elastomer particles of the present invention and their manufacturing method will be explained in detail using examples and comparative examples. However, the present invention is not limited to these examples. The viscosity values in the examples are measured at 25°C. The properties of each silicone particle were measured as follows. Unless otherwise specified in the examples, silicone particles are a general term for particles made of cured silicone (cured silicone particles) and do not include emulsions.

<Preparation of Silicone Resin-Coated Silicone Elastomer Particles>
The silicone resin-coated silicone elastomer particles of the examples and the silicone resin-coated silicone elastomer particles or silicone elastomer particles of the comparative examples were produced as follows.

[JIS-A hardness and JIS-E hardness of silicone elastomer particles]
The crosslinkable composition for forming silicone elastomer particles, which is the raw material for the silicone elastomer particles, was heated in a heating oven at 150°C for 1 hour to harden it into a sheet, and its hardness was measured using a JIS-A hardness tester or a JIS-E hardness tester as specified in JIS K 6253.

[Average primary particle size of silicone elastomer particles]
The emulsion particles before the addition of the platinum catalyst were measured using a laser diffraction particle size distribution analyzer (Beckman Coulter LS-230 or Malvern Mastersizer 3000), and the median diameter (particle size corresponding to 50% of the cumulative distribution, 50% particle size) was taken as the average primary particle size of the silicone elastomer particles. It is also possible to measure the particle size of the cured silicone particles of the dried silicone elastomer particles using ethanol as a dispersion medium using a laser diffraction particle size distribution analyzer (Malvern Mastersizer 3000). It has been confirmed that the median diameter (particle size corresponding to 50% of the cumulative distribution, D90, μm) and the average primary particle size based on the arithmetic dispersity (indicating the degree of dispersion of the particle size distribution, SD, μm2) of the cured silicone particles in ethanol nearly coincide with the average primary particle size based on the emulsion particle size measurement described above.

[Epoxy equivalent measurement of particle surface]
The epoxy equivalent weight of the particle surface was measured using potentiometric titration for each of the silicone resin-coated silicone elastomer particles that had undergone each epoxy introduction treatment. Specifically, the functional groups of the test sample were chlorinated with excess hydrochloric acid, and then titrated with an alkaline reagent to determine the amount of unreacted hydrochloric acid, thereby quantifying the functional groups (epoxy groups) in the test sample.

[Silicone elastomer particle forming component]
The average formulas of components (A) and (B) used in the examples and comparative examples are listed below. In the following formulas, Me represents a methyl group represented by _CH3- , and Hex represents a hexenyl group represented by _CH2 =CH- _C4H8- . The alkenyl group content represents the proportion of the molecular weight of the vinyl group ( _{CH2 =} CH-) in the molecule.
[Chemical formula 1-1]
_Me2HexSiO- ( _Me2SiO ) _57- (MeHexSiO) _{3- SiHexMe2} ,
The alkenyl group content is 2.7% by mass, and the viscosity is 100 mPa·s.
[Chemical formula 1-2]
Me ₂ HexSiO-(Me ₂ SiO) _110- (MeHexSiO) _1.5
-SiHexMe ₂ ,
The alkenyl group content was 1.0% by mass, and the viscosity was 420 mPa·s.
[Chemical formula 1-3]
_Me2ViSiO- ( _Me2SiO ) ₁₅₀ - _SiViMe2 ,
The alkenyl group content is 0.47% by mass, and the viscosity is 350 mPa·s.
[Chemical formula 1-4]
Me ₂ HexSiO-(Me ₂ SiO) _130- (MeHexSiO) ₁₅
-SiHexMe ₂ ,
The alkenyl group content was 4.0% by mass, and the viscosity was 500 mPa·s.
[Chemical formula 2-1]
(Me ₃ SiO _1/2 ) ₂ (Me ₂ SiO _2/2 ) ₇ (HMeSiO _2/2 ) ₁₂
(MeSiO _3/2 ) ₁ ,
The silicon-bonded hydrogen atom content is 0.84% by mass, and the viscosity is 15 mPa·s.
[Chemical formula 2-2]
_Me3SiO- (HMeSiO) ₄₀ - _SiMe3 ,
The silicon-bonded hydrogen atom content is 1.56% by mass, and the viscosity is 20 mPa·s.
[Chemical formula 3-1]
HO-(Me ₂ SiO) ₃₉ -SiMe ₂ OH,
The silanol group (silicon-bonded hydroxyl group) content is 0.88 wt%, and the viscosity is 80 mPa·s.

[Example 1-1]
89.9 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-1] and 10.1 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-1] were uniformly mixed at room temperature. 12.6 parts by mass of a condensation reaction product of tetraethoxysilane (an oligomer mixture with an average pentamer) and 5.4 parts by mass of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution at 25 ° C consisting of 1.7 parts by mass of polyoxyethylene sorbitan laurate, 0.3 parts by mass of polyoxyalkylene alkyl ester, and 15 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 1.9 μm. Then, 390 parts by mass of pure water was added to dilute the emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in an amount such that the platinum metal in the composition was 10 ppm by mass) was prepared as an aqueous dispersion using polyoxyethylene sorbitan laurate and pure water, and this dispersion was added to the emulsion and stirred. After this emulsion was allowed to stand at 50°C for 1 hour to carry out a hydrosilylation reaction, the aqueous suspension was cooled to 10-15°C, and then 60 parts by mass of 28% aqueous ammonia was added. The pH of the liquid at this time was 11. While cooling and stirring, 7.5 parts by mass of glycidoxypropyl(methyl)dimethoxysilane was slowly added dropwise over 20 minutes or more, and stirring was continued for a total of 3 hours at this temperature. The liquid temperature was then raised to 50°C, and the mixture was stirred for 5 hours to carry out a condensation reaction, producing a uniform aqueous suspension of silicone elastomer particles coated with silicone resin. The aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, model number: FJD-2B) to yield silicone elastomer particles coated with an epoxy group-containing silicone resin. The resulting silicone elastomer particles had a JIS-A hardness of 70 and a JIS-E hardness of 74.

[Example 1-2]
89.9 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-1] and 10.1 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-1] were uniformly mixed at room temperature. 12.6 parts by mass of a condensation reaction product of tetraethoxysilane (an oligomer mixture with an average pentamer) and 5.4 parts by mass of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution at 25 ° C consisting of 2.6 parts by mass of polyoxyethylene sorbitan laurate, 0.4 parts by mass of polyoxyalkylene alkyl ester, and 13 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 4.2 μm. Then, 1,000 parts by mass of pure water was added to dilute the mixture to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in an amount such that the platinum metal in the composition was 10 ppm by mass) was prepared as an aqueous dispersion using polyoxyethylene sorbitan laurate and pure water, and this dispersion was added to the emulsion and stirred. The emulsion was then allowed to stand at 50°C for 1 hour to carry out a hydrosilylation reaction. The aqueous suspension was then cooled to 10-15°C, and 60 parts by mass of 28% aqueous ammonia was added. The pH of the solution at this time was 11. While cooling and stirring, 9.2 parts by mass of glycidoxypropyl(methyl)dimethoxysilane was slowly added dropwise over 20 minutes or more, and stirring was continued for a total of 3 hours at this temperature. The liquid temperature was then raised to 50°C, and the mixture was stirred for 5 hours to carry out a condensation reaction, producing a uniform aqueous suspension of silicone elastomer particles coated with an epoxy group-containing silicone resin. The aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, FJD-2B) to yield silicone elastomer particles coated with an epoxy group-containing silicone resin. The resulting silicone elastomer particles had a JIS-A hardness of 70 and a JIS-E hardness of 74.

[Examples 1-3]
97.4 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-2] and 2.6 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-1] were uniformly mixed at room temperature. 12.6 parts by mass of a condensation reaction product of tetraethoxysilane (an oligomer mixture with an average pentamer) and 5.4 parts by mass of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution at 25 ° C consisting of 1.4 parts by mass of polyoxyethylene sorbitan laurate, 0.2 parts by mass of polyoxyalkylene alkyl ester, and 13 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 4.2 μm. Then, 380 parts by mass of pure water was added to dilute the emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in an amount such that the platinum metal in the composition was 10 ppm by mass) was prepared as an aqueous dispersion using polyoxyethylene sorbitan laurate and pure water, and this was added to the emulsion and stirred. After this emulsion was allowed to stand at 50°C for 1 hour to carry out a hydrosilylation reaction, the aqueous suspension was cooled to 10-15°C, and then 60 parts by mass of 28% aqueous ammonia was added. The pH of the liquid at this time was 11. While cooling and stirring, 9.0 parts by mass of glycidoxypropyl(methyl)dimethoxysilane was slowly added dropwise over 20 minutes or more, and stirring was continued for a total of 3 hours at this temperature. The liquid temperature was then raised to 50°C, and the mixture was stirred for 5 hours to carry out a condensation reaction, producing a uniform aqueous suspension of silicone elastomer particles coated with an epoxy group-containing silicone resin. The aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, FJD-2B) to yield silicone elastomer particles coated with an epoxy group-containing silicone resin. The resulting silicone elastomer particles had a JIS-A hardness of 25 and a JIS-E hardness of 36.

[Comparative Example 1-1]
90 parts by weight of a polyorganosiloxane represented by the average formula [Chemical Formula 1-1] and 10 parts by weight of a polyorganosiloxane represented by the average formula [Chemical Formula 2-1] were uniformly mixed at room temperature. Next, this composition was dispersed in a 25 ° C aqueous solution consisting of 1.7 parts by weight of polyoxyethylene sorbitan laurate, 0.3 parts by weight of polyoxyalkylene alkyl ester, and 15 parts by weight of pure water, and further uniformly emulsified using a colloid mill. The average primary particle size was 2.2 μm. Then, 390 parts by weight of pure water was added to dilute the mixture to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (an amount such that the platinum metal in this composition was 10 ppm by weight) was prepared as an aqueous dispersion with polyoxyethylene sorbitan laurate and pure water, and added to the emulsion after stirring. The emulsion was then allowed to stand at 50 ° C for 1 hour to undergo a hydrosilylation reaction. After that, the temperature was lowered to 15 ° C, and 60 parts by weight of 28% aqueous ammonia was added. The pH of the liquid at this time was 11. When 18 parts by mass of 3-glycidyloxypropyltrimethoxysilane was added dropwise while stirring and maintaining the temperature at 15°C, a gel was formed. Therefore, the silicone elastomer particles of Comparative Example 1-1 were not used in the preparation of the curable organic resin composition described below.

[Comparative Example 1-2]
84 parts by weight of a polyorganosiloxane represented by the average formula [Chemical Formula 1-4] and 16 parts by weight of a polyorganosiloxane represented by the average formula [Chemical Formula 2-1] were uniformly mixed at room temperature. 14 parts by weight of a condensation reaction product of tetraethoxysilane (an oligomer mixture with an average pentamer) and 6 parts by weight of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution at 25 ° C consisting of 1.7 parts by weight of polyoxyethylene sorbitan laurate, 0.3 parts by weight of polyoxyalkylene alkyl ester, and 20 parts by weight of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 2.1 μm. Then, 370 parts by weight of pure water was added to dilute the emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in an amount that would result in 10 ppm platinum metal by mass in the composition) was added to the emulsion to form an aqueous dispersion using polyoxyethylene sorbitan laurate and pure water, and the resulting dispersion was stirred. The emulsion was then allowed to stand at 50°C for 1 hour to carry out a hydrosilylation reaction, after which 17.5 parts by mass of 28% aqueous ammonia was added. The pH of the resulting solution was 11. The mixture was further stirred for 5 hours to carry out a condensation reaction, yielding a uniform aqueous suspension of silicone resin-coated silicone elastomer particles. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, FJD-2B) to yield silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 70 and a JIS-E hardness of 74.

[Comparative Examples 1-3]
89.9 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-1] and 10.1 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-1] were uniformly mixed at room temperature. 12.6 parts by mass of a condensation reaction product of tetraethoxysilane (an oligomer mixture with an average pentamer) and 5.4 parts by mass of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution at 25 ° C consisting of 2.6 parts by mass of polyoxyethylene sorbitan laurate, 0.4 parts by mass of polyoxyalkylene alkyl ester, and 13 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 4.2 μm. Then, 1,000 parts by mass of pure water was added to dilute the mixture to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in an amount that would result in 10 ppm platinum metal by mass in the composition) was added to the emulsion to form an aqueous dispersion using polyoxyethylene sorbitan laurate and pure water, and the resulting dispersion was stirred. The emulsion was then allowed to stand at 50°C for 1 hour to carry out a hydrosilylation reaction, after which 60 parts by mass of 28% aqueous ammonia was added. The pH of the resulting solution was 11. The mixture was further stirred for 5 hours to carry out a condensation reaction, yielding a uniform aqueous suspension of silicone resin-coated silicone elastomer particles. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, FJD-2B) to yield silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 70 and a JIS-E hardness of 74.

[Comparative Examples 1-4]
97.4 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-2] and 2.6 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-1] were uniformly mixed at room temperature. 14 parts by mass of a condensation reaction product of tetraethoxysilane (an oligomer mixture with an average pentamer) and 6 parts by mass of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution at 25 ° C consisting of 1.9 parts by mass of polyoxyethylene sorbitan laurate, 0.3 parts by mass of polyoxyalkylene alkyl ester, and 22 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 1.9 μm. Then, 440 parts by mass of pure water was added to dilute the emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in an amount such that the platinum metal content in the composition was 10 ppm by mass) was prepared as an aqueous dispersion using polyoxyethylene sorbitan laurate and pure water. This dispersion was then added to the emulsion and stirred. The emulsion was then allowed to stand at 50°C for 1 hour to carry out a hydrosilylation reaction, after which 17.5 parts by mass of 28% aqueous ammonia was added. The pH of the solution at this stage was 11. The mixture was further stirred for 5 hours to carry out a condensation reaction, yielding a uniform aqueous suspension of silicone resin-coated silicone elastomer particles. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, FJD-2B) to yield silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 25 and a JIS-E hardness of 36.

[Comparative Examples 1-5]
8.6 parts by mass of a polyorganosiloxane represented by [Chemical Formula 2-2], 81.6 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 3-1], and 4.3 parts by mass of glycidoxypropyltrimethoxysilane were uniformly mixed at room temperature. After adding 0.7 parts by mass of stannous octoate, this composition was dispersed in a 25 ° C aqueous solution consisting of 2.8 parts by mass of polyoxyethylene sorbitan laurate, 1.9 parts by mass of polyoxyethylene isodecyl ether, and 85 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 2.3 μm. Then, 177 parts by mass of pure water was added and diluted to prepare an emulsion. This emulsion was aged at 20 ° C for 5 hours, and a condensation reaction was carried out. The mixture was then heated to 60 ° C with stirring and maintained at that temperature for 90 minutes. The temperature was then raised to 80°C and maintained at this temperature for 1 hour while stirring to complete the condensation reaction, yielding a uniform aqueous suspension of silicone rubber particles. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, FJD-2B) to yield silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 40.

[Comparative Examples 1-6]
95.8 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-3] and 4.2 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-1] were uniformly mixed at room temperature. Next, this composition was dispersed in a 25°C aqueous solution consisting of 0.5 parts by mass of polyoxyalkylene alkyl ester and 33 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle size was 5.0 μm. The mixture was then diluted with 600 parts by mass of pure water to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (an amount such that the platinum metal in this composition was 10 ppm by mass) was prepared as an aqueous dispersion using polyoxyethylene sorbitan laurate and pure water, and added to the emulsion after stirring. The emulsion was then allowed to stand at 25°C for 3 hours to undergo a hydrosilylation reaction. The aqueous suspension was then heated to 65°C and aged for 1 hour. After aging, the mixture was further heated to 85°C and held for an additional hour to complete the hydrosilylation and reaction of residual SiH groups, yielding a uniform aqueous suspension of silicone rubber particles. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, FJD-2B) to yield silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 33 and a JIS-E hardness of 43.

<Preparation of Curable Organic Resin Composition>
Each of the particles of Examples 1-1 to 1-3 and Comparative Examples 1-2 to 1-6 obtained in the preparation of the silicone resin-coated silicone elastomer particles described above was used as a silicone compound to produce a curable organic resin composition.

Specifically, the curable organic resin composition was produced as follows.
A mixture was obtained by mixing the components in the amounts (parts by mass) shown in Table 2 at room temperature using a mixer. Next, the mixture was heated and kneaded at a temperature of 70° C. or higher and 110° C. or lower. Then, the mixture was cooled to room temperature to obtain a curable organic resin composition.

Details of each raw material component are as follows:
(epoxy resin)
Epoxy resin 1: Biphenyl type epoxy resin (Mitsubishi Chemical Corporation, product number: YX-4000H)
Epoxy resin 2: a mixture of trisphenylmethane epoxy resin (75% by mass) and biphenyl epoxy resin (25% by mass) (Mitsubishi Chemical Corporation, product number: YL6677)

(hardening agent)
Hardener 1: Trisphenylmethane phenolic resin (Air Water Inc., HE910-20)

(Inorganic filler)
Inorganic filler 1: Spherical silica with an average particle size of 19 μm (Nippon Steel Sumikin Materials Co., Ltd., Micron Company, product number: S430-5)
Inorganic filler 2: Spherical silica with an average particle size of 0.5 μm (Admatechs Co., Ltd., product number: SC-2500-SQ)
Inorganic filler 3: Spherical silica with an average particle size of 1.5 μm (Admatechs Co., Ltd., product number: SC-5500-SQ)

(Curing accelerator)
Curing accelerator 1: 2,3-dihydroxynaphthalene (Tokyo Chemical Industry Co., Ltd.)
Curing accelerator 2: Triphenylphosphine (Tokyo Chemical Industry Co., Ltd.)

(Coupling Agent)
Coupling agent 1: N-phenyl-3-aminopropyltrimethoxysilane (Dow Toray Co., Ltd., Z-6883)

(Release agent)
Release agent: Glycerin trimontanate ester (Clariant Japan Co., Ltd., Ricorb WE-4)

(Silicone Compound)
Silicone compounds:
In Examples 2-1 and 2-2, the epoxy group-containing silicone elastomer particles of Examples 1-1 and 1-2 were used, respectively.
In addition, the silicone elastomer particles of Comparative Examples 1-2, 1-3, 1-4, and 1-5 were used as Comparative Examples 2-1, 2-2, 2-3, and 2-4, respectively.

<Preparation of cured product (compression molding)>
Cured products were prepared using each of the curable organic resin compositions listed in Table 2, prepared as described above. A mold consisting of upper, middle, and lower molds was used for molding. The middle mold was cut out to a size of 100 mm x 10 mm x 4 mm or 50 mm x 50 mm x 1 mm. An amount of curable resin composition corresponding to the volume of the cutout portion of the middle mold placed on the lower mold was placed and sandwiched between the upper mold and molded using a manual hydraulic heating press at a mold temperature of 175°C, 2.4 MPa, and a curing time of 10 minutes to obtain test pieces measuring 100 mm long, 10 mm wide, and 4 mm thick. The obtained test pieces were then heat-treated at 175°C for 4 hours and then allowed to cool. Cured products measuring 4 mm x 4 mm x 10 mm were obtained by cutting the long sides of 100 mm x 10 mm x 4 mm cured compositions using a microcutter to a width of 4 mm. In this manner, cured products for evaluation were prepared. Unless otherwise specified below, test pieces were prepared under these conditions (compression molding).

<Evaluation of mechanical properties of cured product>
The mechanical properties of the resulting cured product were evaluated.
[Linear expansion coefficient of cured product]
The linear expansion coefficient of the cured product measuring 4 mm x 4 mm x 10 mm was measured using a thermomechanical analyzer (TMA7100, manufactured by Hitachi High-Tech Science Corporation). The measurement was performed under conditions of a temperature rise rate of 5°C/min from -30°C to 300°C. The measurement data was analyzed, and the average linear expansion coefficient [ppm/°C] between 180 and 220°C was defined as CTE2. The obtained evaluation results are shown in Table 3.

[Flexural modulus of cured product]
The flexural modulus [MPa (N/mm ^{2 )} ] at 25°C of a cured product measuring 100 mm long x 10 mm wide x 4 mm thick was evaluated using a tensile tester (Shimadzu Corporation, AGS-X, 10N-10kN).
As a result of the above evaluation, the elastic moduli of the cured products of Examples 2-1 and 2-3 were 14,500 MPa and 14,300 MPa, respectively, and the elastic modulus of the cured product of Comparative Example 2-1 was 15,580 MPa.

[Izod impact test of cured product]
Using a transfer molding machine, the curable resin compositions shown in Table 1 were injected into the mold cavity under conditions of a mold temperature of 175°C, a molding pressure of 9.8 MPa, and a curing time of 3 minutes, and test pieces measuring 50 mm in length, 10 mm in width, and 4 mm in thickness were measured without notching in accordance with JIS K7110, and the Izod strength [kJ/m ² ] was evaluated.

[Molding shrinkage rate]
For each of the Examples and Comparative Examples, the shrinkage percentage of the obtained cured product was measured as follows. First, a curable resin composition shown in Table 1 was injected into a mold cavity using a transfer molding machine under conditions of a mold temperature of 175°C, a molding pressure of 9.8 MPa, and a curing time of 3 minutes to prepare a disk-shaped first test piece. Next, the first test piece was cooled to 25°C. The shrinkage percentage _S1 (%) was calculated as follows from the inner diameter of the mold cavity at 175°C and the outer dimensions of the first test piece at 25°C.
S ₁ ={(inner diameter dimension of mold cavity at 175° C.)−(outer diameter dimension of first test piece at 25° C.)}/(inner diameter dimension of mold cavity at 175° C.)×100.
The first test piece was then post-cured in an oven at 175° C. for 4 hours to prepare a second test piece. The second test piece was then cooled to 25° C. The shrinkage ratio _S2 (%) was calculated from the inner diameter of the mold cavity at 175° C. and the outer dimensions of the second test piece at 25° C. as follows:
S ₂ = {(inner diameter of mold cavity at 175°C) - (outer diameter of second test piece at 25°C)} / (inner diameter of mold cavity at 175°C) × 100
The evaluation results are shown in Table 4.

[Temperature cycle test]
Using a transfer molding machine, the curable resin compositions shown in Table 1 were injected into a mold cavity under conditions of a mold temperature of 175°C, a molding pressure of 9.8 MPa, and a curing time of 3 minutes to produce cured products measuring 100 mm in length, 10 mm in width, and 4 mm in thickness. Next, a temperature cycle was applied using hot and cold air in a test tank. A temperature cycle test was performed up to 1,000 times, with a low temperature of -40°C and a high temperature of 150°C, each held for 30 minutes. The resulting cured products were evaluated for flexural strength [MPa (N/ ^mm2 )], breaking energy [mJ], and Izod impact value [kJ/m2] at 25°C using a tensile tester (Shimadzu Corporation, AGS-X, 10N-10kN). Furthermore, the bending strength, breaking energy and Izod impact value of the cured product (test piece) after the temperature cycle were measured by the above-mentioned methods, and the values obtained by dividing these values by the initial values before the temperature cycle were defined as the relative strength, relative energy and relative Izod strength, respectively.
The evaluation results are shown in Tables 5 and 6.

As shown in Table 3, in an evaluation using a curable resin composition containing silicone elastomer particles coated with a silicone resin containing epoxy groups (Examples 2-1 and 2-3), the CTE2 of the cured product obtained from the curable resin composition was reduced compared to a curable resin composition containing silicone elastomer particles not containing epoxy groups (Comparative Examples 2-1 and 2-3) and a curable resin composition containing silicone elastomer particles not coated with a silicone resin (Comparative Example 2-4). Furthermore, the elastic moduli of the cured products of Examples 2-1 and 2-3 were improved compared to the elastic modulus of the cured product of Comparative Example 2-1. This demonstrates that the addition of the silicone resin-coated silicone elastomer particles of the present invention can contribute to stress relaxation.
Furthermore, as shown in Table 4, the curable resin composition containing silicone elastomer particles coated with a silicone resin containing epoxy groups (Example 2-3) had reduced mold shrinkage rates S1 and S2 compared to the curable resin composition containing silicone elastomer particles not containing epoxy groups (Comparative Example 2-3), the curable resin composition containing silicone elastomer particles not coated with a silicone resin (Comparative Example 2-5), and the curable resin composition not containing silicone elastomer particles (Comparative Example 2-6), thereby achieving favorable results. This is thought to be because the epoxy groups on the surface of the silicone elastomer particles improved adhesion to the curable resin.
Furthermore, as shown in Table 5, in an evaluation using a curable resin composition containing silicone elastomer particles coated with a silicone resin containing epoxy groups (Example 2-3), the relative flexural strength and relative breaking energy were improved compared to a curable resin composition containing silicone elastomer particles coated with a silicone resin not containing epoxy groups (Comparative Example 2-3), a curable resin composition containing silicone elastomer particles not containing epoxy groups (Comparative Example 2-5), and a curable resin composition not containing silicone elastomer particles (Comparative Example 2-6).
Furthermore, as shown in Table 6, in evaluations using curable resin compositions containing silicone elastomer particles coated with a silicone resin containing epoxy groups (Examples 2-2 and 2-3), the relative Izod strength was improved compared to a curable resin composition containing silicone elastomer particles not containing epoxy groups (Comparative Example 2-2). This is thought to be because the epoxy groups on the surface of the silicone elastomer particles improved adhesion to the curable resin.
Therefore, it can be seen that the silicone resin-coated silicone elastomer particles of the present invention also have resistance to deterioration, meaning that the additive is less likely to affect the deterioration of the material to which it is added, even when used over a long period of time.

<Observation of fracture surface of cured product>
For the cured epoxy resin products (Example 2-3, Comparative Example 2-1) to which the silicone resin-coated silicone elastomer particles of Example 1-3 and Comparative Example 1-2 had been added, obtained as described above, the fracture surfaces of each cured product were photographed at 2500x magnification using a scanning electron microscope (SEM, device name: Hitachi High-Technologies Corporation, Model No. S-3400N) under the following conditions.
<SEM conditions>
Degree of vacuum: <1 Pa
Acceleration voltage: 15.0 kV
Probe current: 30 μA
The silicone resin-coated silicone elastomer particles of Example 1-3 have a silicone resin coating and have been subjected to an epoxy introduction treatment, while the silicone resin-coated silicone elastomer particles of Comparative Example 1-2 have a silicone resin coating but have not been subjected to an epoxy introduction treatment.
The photographs show that numerous spherical holes are formed on the fracture surface of Comparative Example 2-1 (FIG. 1), and that the particles have dissociated and peeled off at the interface with the resin. In contrast, the fracture surface of Example 2-3 (FIG. 2) shows that the spherical holes are not present, and the particles have broken while still adhering to the resin. In other words, it can be seen that the silicone resin-coated silicone elastomer particles of the examples have effectively improved adhesion to the resin, and do not dissociate at the particle-resin interface due to expansion and contraction. In other words, the silicone resin-coated silicone elastomer particles of the present invention have a silicone resin coating and have been subjected to an epoxy incorporation treatment, and therefore have resistance to deterioration.

The present invention provides silicone resin-coated silicone elastomer particles that maintain dispersibility in the material to which they are added, contribute to stress relief in the material, and are also resistant to deterioration, as well as a method for producing the same. The present invention also provides additives for organic resins, paints or coating agents, curable organic resin compositions, cured products, and semiconductor devices containing silicone resin-coated silicone elastomer particles that can reduce the coefficient of thermal expansion and modulus of elasticity, as well as methods for producing the semiconductor devices.

Claims (19)

Silicone resin-coated silicone elastomer particles comprising silicone elastomer particles and a silicone resin coating that coats a part or all of the surface of the silicone elastomer particles,
the silicone elastomer particles have a structure in which at least two silicon atoms are crosslinked by a silalkylene group having 2 to 20 carbon atoms;
The silicone resin coating
i) M siloxane units represented by R ₃ SiO _1/2 (R is a monovalent organic group); ii) D siloxane units represented by R ₂ SiO _2/2 (R is a monovalent organic group);
iii) T siloxane units represented by RSiO _3/2 (R is a monovalent organic group), and
iv) Q siloxane units represented by SiO _4/2 ;
and one or more silicone resins selected from the group consisting of one or a combination of two or more silicone resins selected from the group consisting of:
The silicone resin-coated silicone elastomer particles have an epoxy group-containing hydrocarbon group in a siloxane unit selected from the siloxane units i) to iii) of the silicone resin. The silicone resin-coated silicone elastomer particles according to claim 1, wherein the amount of the silicone resin coating is in the range of 5.0 to 40.0 parts by mass per 100 parts by mass of the silicone elastomer particles. The silicone resin-coated silicone elastomer particles according to claim 1, having an average primary particle diameter of 0.1 to 100 μm as measured by laser diffraction scattering. The silicone resin-coated silicone elastomer particles according to claim 1, wherein the silicone elastomer particles in a state not coated with the silicone resin coating have a JIS-A hardness of 80 or less and a JIS-E hardness of 1 or more, measured by curing the uncured crosslinkable composition for forming silicone elastomer particles into a sheet. The silicone resin-coated silicone elastomer particles according to claim 1, having a silicon atom-bonded hydrogen content per unit mass of 300 ppm or less. the silicone resin coating comprises a DQ silicone resin composed of D siloxane units represented by R ¹ ₂ SiO _2/2 (wherein R ¹ is independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms and an epoxy group, or an aryl group having 6 to 20 carbon atoms and an epoxy group), and Q siloxane units represented by SiO _4/2 ;
2. The silicone resin-coated silicone elastomer particles according to claim 1, wherein the ratio of the D siloxane units to the Q siloxane units is within the range of 8:2 to 0.8:9.2. the silicone resin coating comprises a DQ silicone resin formed from a condensation reaction product of a diorganodialkoxysilane and a tetraalkoxysilane;
At least a portion of the silane in the diorganodialkoxysilane has an epoxy group-containing hydrocarbon group,
2. The silicone resin-coated silicone elastomer particles according to claim 1, wherein the molar ratio of the diorganodialkoxysilane-derived D units to the tetraalkoxysilane-derived Q units is within the range of 8:2 to 0.8:9.2. Regarding the silicone elastomer particles in a state where they are not coated with the silicone resin coating, the crosslinkable composition for forming the silicone elastomer particles before curing is
(a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in each molecule;
(b) an organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms in each molecule; and
(c) a hydrosilylation reaction catalyst;
Contains
the molar ratio of the content of alkenyl groups (Alk (mol)) in the component (a) to the content of hydrogen atoms bonded to silicon atoms (H (mol)) in the component (b) is H/Alk=0.5 to 1.5;
2. The silicone resin-coated silicone elastomer particles according to claim 1, which is a crosslinkable composition having a crosslinkability in the range of 1.0 to 1.0. A method for producing silicone resin-coated silicone elastomer particles, comprising:
The manufacturing method includes:
Step (I):
(a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule;
(b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule, and (d) a silane-based compound;
emulsifying the mixture in water;
Step (II):
(c) curing the emulsion obtained in step (I) in the presence of a hydrosilylation reaction catalyst to obtain silicone elastomer particles; and
Step (III):
a step of coating a part or all of the surfaces of the silicone elastomer particles with the (d) silane-based compound and, optionally, the (e) silane-based compound-containing silicone resin added during the step (III), simultaneously with or after the step (II);
Including,
When the (e) silane-based compound is added, at least one of the (d) silane-based compound and the (e) silane-based compound contains a hydrolyzable silane having an epoxy group-containing hydrocarbon group,
When the silane-based compound (e) is not added, the silane-based compound (d) contains a hydrolyzable silane having an epoxy group-containing hydrocarbon group. The (d) silane-based compound includes tetraalkoxysilane or a condensation reaction product thereof,
The method according to claim 9 , wherein the hydrolyzable silane having an epoxy group-containing hydrocarbon group or a condensation product thereof comprises a diorganodialkoxysilane having an epoxy group-containing hydrocarbon group or a condensation product thereof. An additive for organic resins, comprising the silicone resin-coated silicone elastomer particles described in any one of claims 1 to 8. The organic resin additive according to claim 11, wherein the organic resin comprises an epoxy resin. A paint or coating agent comprising the silicone resin-coated silicone elastomer particles described in any one of claims 1 to 8. The paint or coating agent according to claim 13, wherein the organic resin comprises an epoxy resin. A curable organic resin composition comprising the silicone resin-coated silicone elastomer particles according to any one of claims 1 to 8 and a curable organic resin. The curable organic resin composition according to claim 15, wherein the curable organic resin comprises an epoxy resin. A cured product obtained by curing the curable organic resin composition described in claim 15. A semiconductor device comprising the cured product described in claim 17. A method for manufacturing a semiconductor device, comprising curing the curable organic resin composition described in claim 15.