Silicone resin-coated silicone elastomer particles, additive for organic resin, and other uses

Abstract

The present invention pertains to silicone resin-coated silicone elastomer particles comprising silicone elastomer particles and a silicone resin coating that covers a part or all of the surface of the silicone elastomer particles, wherein the silicone elastomer particles which have not been covered with the silicone resin coating have a JIS-A hardness of 45 or less as measured by curing a crosslinking composition for forming the silicone elastomer particles before curing into a sheet shape and a JIS-E hardness of 2 or more; the silicone elastomer particles have a structure in which at least two silicon atoms are crosslinked via a C2-20 silalkylene group, and the silicone resin coating contains one or more silicone resins (except for a silicone resin only consisting of T siloxane unit indicated below) selected from silicone resins containing a combination of two or more units selected from i) M siloxane unit represented by R3SiO1 / 2 (wherein R is a monovalent organic group); ii) D siloxane unit represented by R2SiO2 / 2 (wherein R is a monovalent organic group); iii) T siloxane unit represented by RSiO3 / 2 (wherein R is a monovalent organic group); and iv) Q siloxane unit represented by SiO4 / 2.

Description

Silicone resin coated silicone elastomer particles and additives for organic resins and other uses

[0001] The present invention relates to silicone resin-coated silicone elastomer particles. The present invention also relates to an additive for organic resins, a paint or coating agent, a curable organic resin composition, a cured product, a semiconductor device, and a method for producing a semiconductor device, each of which contains the silicone resin-coated silicone elastomer particles.

[0002] Conventionally, various additives have been investigated for modifying the physical properties of a wide range of materials such as paints, coating agents, thermosetting organic resins, and thermoplastic organic resins, specifically for reducing elasticity, thermal expansion coefficient, molding shrinkage, etc. In particular, with regard to resin materials used in electronic components, with the recent trend toward miniaturization of various electronic devices, additives capable of further reducing elasticity, thermal expansion coefficient, molding shrinkage, etc. of resin materials used in electronic components have been investigated.

[0003] Japanese Patent Application Publication No. 2013-010940 Japanese Patent Application Publication No. 2020-023643 International Publication No. 2021 / 149727 International Publication No. 2019 / 124418 International Publication No. 2020 / 137913

[0004] More specifically, with the miniaturization of electronic devices such as mobile phones, smartphones, ultra-thin LCD displays, plasma TVs, and lightweight laptops, the integration and packaging of electronic components, such as semiconductor devices, used in these electronic devices is becoming increasingly dense. Furthermore, there is an increasing demand for encapsulation of large-area devices, such as wafer-level packages and panel-level packages. Resin materials used in these electronic components have problems such as warping after molding and delamination between components during the solder reflow process, creating a need to reduce thermal stresses that arise 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 that arise 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 stresses. Incidentally, thermal stress is generated by residual strains caused by volumetric changes in the encapsulating composition. To reduce this residual strain, it is necessary to suppress both the curing shrinkage caused by volumetric reduction due to the polymerization / crosslinking reaction of the encapsulating resin composition and the thermal shrinkage caused by cooling after encapsulation.

[0005] For example, Patent Document 1 (JP-A-2003-134999) discusses increasing the filler content of epoxy resins in order to reduce thermal stress. While increasing the filler content can reduce the coefficient of thermal expansion of the epoxy resin, this approach may not be effective enough to suppress warpage when the support surface area is large, as in wafer-level packages and panel-level packages. Furthermore, the elastic modulus of the cured product increases and the strength of the epoxy resin decreases, potentially resulting in damage to Si chips and substrates during manufacturing processes such as solder reflow processes or heat cycle tests during use.

[0006] Patent Documents 2 and 3 disclose another method for reducing thermal stress, which involves adding an epoxy-modified silicone to an epoxy resin to lower its elastic modulus. While this method is effective in reducing thermal stress, it does not sufficiently reduce the thermal expansion coefficient (linear expansion coefficient). The present applicants have also proposed organic resin additives (Patent Documents 4 and 5) containing silicone elastomer particles coated with a silicone resin containing branched units such as Q units and T units. While these silicone elastomer particles have excellent dispersibility in organic resin varnishes and have a certain effect on stress relaxation in composites with glass fabrics, there is still room for further improvement in terms of reducing the shrinkage, thermal expansion coefficient, or elastic modulus during molding of epoxy resins that do not contain volatile solvents, as described below. Furthermore, there is no mention of using relatively soft particles for purposes such as preventing deterioration.

[0007] On the other hand, it is also possible to use a relatively soft powder (not having a core-shell structure) to reduce elasticity, etc. However, while the use of such a soft powder reduces the elasticity of the material, soft powders generally tend to aggregate and have poor dispersibility within the material to which they are added, which can result in a decrease in the strength of the material.

[0008] Thus, there is a need for additives that can effectively reduce the coefficient of thermal expansion or modulus of elasticity by adding them to a wide range of materials, including resin materials used in electronic components, such as paints, coating agents, thermosetting organic resins, and thermoplastic organic resins, in order to relieve internal stresses that may occur during their manufacture or use. Furthermore, such additives must also have degradation resistance that makes them less susceptible to degradation of the materials to which they are added over long periods of use.

[0009] Therefore, an object of the present invention is 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. Another object of the present invention is to provide an organic resin additive, a paint or coating agent, a curable organic resin composition, a cured product, and a semiconductor device, each containing the silicone resin-coated silicone elastomer particles, which can reduce the thermal expansion coefficient, low shrinkage rate, and elastic modulus, and make the material less susceptible to thermal deterioration, as well as a manufacturing method for manufacturing the semiconductor device.

[0010] [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, wherein the silicone elastomer particles in a state where they are not coated with the silicone resin coating have a JIS-A hardness of 45 or less and a JIS-E hardness of 1 or more, measured after curing a crosslinkable composition for forming silicone elastomer particles into a sheet, and 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, and the silicone resin coating has the following characteristics: i) R ３ SiO １／２ (R is a monovalent organic group) ２ SiO ２／２ (R is a monovalent organic group), and iii) a D siloxane unit represented by RSiO ３／２ (R is a monovalent organic group), and iv) SiO ４／２and a silicone resin-coated silicone elastomer particle comprising one or more silicone resins (excluding silicone resins consisting only of T siloxane units) selected from silicone resins consisting of a combination of two or more types selected from the group consisting of Q siloxane units represented by the formula (iv), and M / D / T siloxane units represented by the formula (i) to (iii). [2] The silicone resin-coated silicone elastomer particle according to the formula (1), wherein the silicone resin coating comprises one or more silicone resins selected from silicone resins consisting of Q siloxane units represented by the formula (iv), and one or more combinations of M / D / T siloxane units represented by the formula (i) to (iii). [3] The silicone resin-coated silicone elastomer particles according to [1], wherein the silicone resin coating comprises one or more silicone resins selected from the group consisting of a silicone resin comprising the D siloxane unit of ii) and the Q siloxane unit of iv), and a silicone resin comprising two types of units, the D siloxane unit of ii) and the Q siloxane unit of iv), and one or two types of units selected from the M siloxane unit of i) and the T siloxane unit of iii). [4] The silicone resin-coated silicone elastomer particles according to any one of [1] to [3], wherein the average primary particle diameter measured by a laser diffraction scattering method is 0.1 to 100 μm. [5] The silicone resin coating comprises one or more silicone resins selected from the group consisting of a silicone resin comprising the D siloxane unit of ii) and the Q siloxane unit of iv). １ ２ SiO ２／２ (R １ are independently a D siloxane unit represented by 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 SiO ４／２and Q siloxane units represented by the following formula (1): wherein the DQ silicone resin and the Q siloxane units are in a ratio of 8:2 to 0.8:9.2 by mass. [6] The silicone resin-coated silicone elastomer particles according to any one of [1] to [5], wherein the silicone resin-coated silicone elastomer particles have a silicon atom-bonded hydrogen content of 300 ppm or less per unit mass. [7] The silicone resin-coated silicone elastomer particles according to any one of [1] to [6], wherein the crosslinkable composition for forming the silicone elastomer particles before curing contains, for the silicone elastomer particles not coated with the silicone resin coating, (a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms per molecule, (b) an organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms per molecule, and (c) a hydrosilylation reaction catalyst, wherein the molar ratio of the content of alkenyl groups (Alk (mol)) in component (a) to the content of hydrogen atoms bonded to silicon atoms (H (mol)) in component (b) is in the range of H / Alk = 0.5 to 1.5. [8] An additive for organic resins, comprising the silicone resin-coated silicone elastomer particles according to any one of [1] to [7]. [9] The organic resin additive according to [8], wherein the organic resin comprises an epoxy resin.

[10] A paint or coating agent comprising the silicone resin-coated silicone elastomer particles according to any one of [1] to [7].

[11] The paint or coating agent according to

[10] , wherein the organic resin comprises an epoxy resin.

[12] A curable organic resin composition comprising the silicone resin-coated silicone elastomer particles according to any one of [1] to [7] and a curable organic resin.

[13] The curable resin composition according to

[12] , wherein the curable organic resin comprises an epoxy resin.

[14] A cured product obtained by curing the curable organic resin composition according to

[12] .

[15] A semiconductor device comprising the cured product according to

[14] .

[16] A method for producing a semiconductor device, comprising curing the curable organic resin composition according to

[12] .

[0011] According to the present invention, it is possible to provide silicone resin-coated silicone elastomer particles that can contribute to stress relaxation of a material to which they are added while maintaining dispersibility in the material, and that also have deterioration resistance.The present invention also provides an additive for organic resins, a paint or coating agent, a curable organic resin composition, a cured product, and a semiconductor device, which contain the silicone resin-coated silicone elastomer particles and are capable of reducing the thermal expansion coefficient, molding shrinkage rate, and elastic modulus, and have deterioration resistance, as well as a manufacturing method for manufacturing the semiconductor device.

[0012] 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, for the numerical ranges described in this specification, the upper and lower limits can be arbitrarily combined. 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 in this specification. 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 in this specification. In addition, for example, when a numerical range described in this specification, such as "60 to 100," means a range of "60 or more and 100 or less."

[0013] <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 comprising silicone elastomer particles and a silicone resin coating that coats part or all of the surface of the silicone elastomer particles. Furthermore, in the silicone resin-coated silicone elastomer particles of this embodiment, the silicone elastomer particles in a state where they are not coated with a silicone resin coating have a JIS-A hardness of 45 or less and a JIS-E hardness of 1 or more, as measured after curing a crosslinkable composition for forming silicone elastomer particles into a sheet. Furthermore, 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, and the silicone resin coating comprises: i) R ３ SiO １／２ (R is a monovalent organic group) ２ SiO ２／２ (R is a monovalent organic group), and iii) a D siloxane unit represented by RSiO ３／２ (R is a monovalent organic group), and iv) SiO ４／２ and one or more silicone resins selected from silicone resins consisting of a combination of two or more Q siloxane units represented by the following formula (however, silicone resins consisting only of T siloxane units are excluded).

[0014] [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 bridging the silicon atom and another silicon atom in the siloxane constituting 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.

[0015] The silicone elastomer particles according to this embodiment are not particularly limited in terms of the average primary particle size before being coated with the silicone resin, but preferably have an average primary particle size of 0.1 to 99 μm as measured by laser diffraction scattering. 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 give silicone resin-coated silicone elastomer particles having an average primary particle size of 0.1 to 100 μm as measured by laser diffraction scattering. Needless to say, after coating, the average primary particle size of the particles increases compared to the silicone elastomer particles before coating.

[0016] The shape of the silicone elastomer particles according to this embodiment can be, for example, spherical, spherical, ellipsoidal, or irregular, and is particularly preferably spherical or spherical.In this embodiment, by emulsifying hydrolyzable silanes together with a crosslinking reactive silicone raw material, an aqueous suspension containing spherical silicone elastomer particles coated with silicone resin can be obtained in a single reaction vessel.In addition, spherical silicone resin-coated silicone elastomer particles can be directly produced by drying the aqueous suspension using a vacuum dryer, a hot air circulation oven, or a spray dryer.Therefore, it is not necessarily necessary to separately produce uncoated silicone elastomer particles and coat their surfaces.

[0017] 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 into a material to which they are added, such as an organic resin. When the 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 45 or less and a JIS-E hardness of 1 or more. The JIS-A hardness is obtained by measurement using a JIS-A hardness tester specified in JIS K6253, and the JIS-E hardness is obtained by measurement using a JIS-E hardness tester specified in JIS K6253. When the JIS-A hardness and JIS-E hardness of the rubber sheet obtained by curing the crosslinkable composition for forming silicone elastomer particles into a sheet are measured within the above-mentioned ranges, the resulting silicone elastomer particles tend to be rich in fluidity, dispersibility, silky feel, smoothness, and softness. Furthermore, by setting the JIS-A hardness and JIS-E hardness within the above ranges, it is possible to more effectively improve stress relaxation properties when blended with various materials such as organic resins, and also to obtain excellent handling and workability after coating with silicone resin. Note that the JIS-A hardness, which corresponds to the upper limit of the hardness of the elastomer particles, is preferably 40 or less, and more preferably 30 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 from a practical standpoint, more preferably 2 or more or 3 or more.

[0018] In this embodiment, the upper limit of the hardness of the cured product is specified in JIS-A hardness and the lower limit in JIS-E hardness because when the hardness of the cured product of the composition is in a relatively high range, the level 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 level of hardness can be easily expressed by JIS-E hardness. In addition, when the crosslinkable composition for forming silicone elastomer particles is cured into a sheet, the cured product may have a JIS-E hardness of 50 when the JIS-A hardness is 25, and a JIS-E hardness of 37 when the JIS-A hardness is 8, and a JIS-E hardness of 23.

[0019] The silicone elastomer particles according to this embodiment may further have a silicon-bonded hydrogen atom (hereinafter also referred to as silicon-bonded hydrogen) content 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, even 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, 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 can adequately suppress the generation of hydrogen gas that may occur during long-term storage of these particles.

[0020] A typical method for measuring silicon-bonded hydrogen in silicone elastomer particles is to contact the particles with an alkali and then use gas chromatography (headspace method). For example, an ethanol solution of 40% potassium hydroxide in an amount equal to the unit mass of the silicone elastomer particles is added, the mixture is allowed to stand for one hour, and the hydrogen gas evolved up to the end of the reaction is collected. Then, the amount of the collected hydrogen is measured and quantified using headspace gas chromatography (TCD is preferred as the detector), which makes it possible to identify the content (ppm) of silicon-bonded hydrogen per unit mass.

[0021] [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 hydrogen atoms bonded to silicon atoms in each molecule, and (c) a hydrosilylation reaction catalyst.

[0022] Component (a) is an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms per molecule. Its structure is not particularly limited and may be one or more structures selected from linear, cyclic, network, and partially branched linear structures. Linear organopolysiloxanes are particularly preferred as component (a). 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 the like. Specifically, the viscosity at 25°C is preferably within a range of 1 to 100,000 mPa·s, and particularly preferably within a range of 1 to 10,000 mPa·s.

[0023] From the viewpoint of dispersibility of the silicone elastomer particles, component (a) is a compound represented by the formula: -(CH ３ ) ２Preferably, the organopolysiloxane is a linear organopolysiloxane in which the content of dimethylsiloxane units represented by SiO- is 90 mol% or more of all siloxane units other than siloxane units at the molecular terminals. Similarly, from the standpoint 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 in combination with two or more organohydrogenpolysiloxanes.

[0024] 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 groups. 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 in 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.

[0025] Preferably, component (a) is a linear organopolysiloxane represented by the following chemical formula (1).

[0026] In formula (1), R １１are 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 preferably a methyl group or a phenyl group industrially. ａ is an alkenyl group having 2 to 20 carbon atoms, and is particularly preferably a vinyl group or a hexenyl group. １１ or R ａ where m is a number of 0 or more, and n is a number of 1 or more. Here, m, n, and R represent the vinyl (CH ２ The content of (=CH-) moieties is 0.02 to 5.0 mass %, preferably 0.03 to 3.0 mass %, and the viscosity of component (a) is 20 to 10,000 mPa·s at 25°C.

[0027] 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 of 0 or more, n1 is a positive number, and m1 is a hexenyl group (-(CH ２ ) ４ CH=CH ２ ) in vinyl (CH ２ m1+n1 is a number such that the content of (═CH-) moieties falls within a 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 more, more preferably 100 to 500 mPa·s.

[0028] In addition, component (a) is (R ａ R １１ ２ SiO) ４ The organopolysiloxane may be a branched organopolysiloxane having an alkenyl group at the molecular chain terminal, represented by the formula: ａis an alkenyl group having 2 to 20 carbon atoms, and 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. More specifically, ２ SiO) ４ Si, and (HexMe ２ SiO) ４ The organopolysiloxane may be a branched organopolysiloxane represented by Si 1 , where Vi represents a vinyl group, Me represents a methyl group, and Hex represents a hexenyl group.

[0029] 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 such that b+c=3, d is a positive number, e is 0 or a positive number, and 2b+e≧2. R １１ is the same as the above formula (1). (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 the above formula (1). (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. R １１ is the same as the 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 represent vinyl (CH ２ The values ​​of b, e, f, and h in each formula are numbers that result in the content of (═CH—) moieties being in the range of 0.5 to 3.0 mass%, and more preferably in the range of 1.0 to 2.0 mass%. Furthermore, b, e, f, and h in each formula are numbers that result in the viscosity of the organopolysiloxane represented by each formula being 20 mPa s or more at 25° C., and are more preferably numbers that result in the viscosity being 100 to 500 mPa s.

[0030] 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 crosslinking agent for component (a). It more preferably has at least three silicon-bonded hydrogen atoms per molecule, and the bonding positions of the 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 blending the resulting silicone elastomer particles, it is also preferable to remove in advance, with the exception of intentionally added low polymers, cyclic or linear organopolysiloxanes with low degrees of polymerization (3 to 20) 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.

[0031] 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 groups, and aryl groups such as phenyl groups, with methyl groups being preferred.Furthermore, examples of the molecular structure of the organohydrogenpolysiloxane of component (b) include linear, branched, and branched cyclic structures, or a combination of one or more of these.Note that the number of silicon-bonded hydrogen atoms in one molecule is the average value of all molecules.

[0032] Examples of component (b) include linear, cyclic, or branched polyorganohydrogensiloxanes represented by the following formula: (wherein 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. R １１ is the same as the above formula (1). (wherein r is a positive number of 2 or more, s is 0 or a positive number, and r+s is 4 to 8. R １１ is the same as the above formula (1). (wherein t is 1, 2, or 3, u is 0, 1, or 2, and (t+u)=3; v, w, and x are positive numbers. R １１is the same as the above formula (1). Component (b) is (HSiO ３ / ２ ) units or (R １１ SiO ３ / ２ T-branched polyorganohydrogensiloxane (R １１ is the same as the above formula (1).

[0033] 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, volatilization of component (b) from the crosslinkable composition containing it can be effectively prevented. Furthermore, when the viscosity of component (b) at 25°C is 1,000 mPa·s or less, the curing time of the crosslinkable composition containing such component (b) can be prevented from being too long and the occurrence of curing defects can be suppressed. Examples of such component (b) include, but are not limited to, a dimethylsiloxane-methylhydrogensiloxane copolymer both ends of which are capped with trimethylsiloxy groups, a dimethylsiloxane-methylhydrogensiloxane copolymer both ends of which are capped with dimethylhydrogensiloxy groups, a dimethylpolysiloxane both ends of which are capped with dimethylhydrogensiloxy groups, a methylhydrogenpolysiloxane both ends of which are capped with trimethylsiloxy groups, a cyclic methylhydrogenpolysiloxane, a cyclic methylhydrogensiloxane-dimethylsiloxane copolymer, and a T-branched polymethylhydrogensiloxane.

[0034] 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 0.4 to 1.5. The lower limit of H / Alk is preferably 0.40 or more, 0.45 or more, or 0.50 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 0.9 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. Note that the alkenyl group content (Alk (mol)) means the content (amount of substance (mol)) of vinyl groups in the alkenyl groups.

[0035] 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 catalysts in powders of thermoplastic organic resins such as methyl methacrylate resins, polycarbonate resins, polystyrene resins, and silicone resins. 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. Note that non-platinum metal catalysts such as iron, ruthenium, and iron / cobalt may also be used as catalysts for promoting the hydrosilylation reaction.

[0036] The amount of component (c) added to the crosslinkable composition may be any catalytic amount, and typically, the amount is preferably such that the amount of platinum-based metal contained in component (c) is in the range of 1 to 1,000 ppm, 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 be reduced by washing the silicone elastomer particles with an aqueous solution (preferably at 30°C to 99°C) of one or more surfactants, such as polyoxyethylene alkyl ether or diethylhexyl sodium sulfosuccinate.

[0037] The timing of adding component (c) to the crosslinkable composition can be selected depending on the method for forming the silicone elastomer particles, and it may be added to the composition in advance, 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 in advance, or an emulsion containing component (c) may be added separately to the water.

[0038] The crosslinkable composition may contain a cure retarder, typically 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. and 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 a range of 0.001 to 5 parts by mass per 100 parts by mass of component (a), but can be appropriately determined depending on the type of cure retarder used, the properties and amount of the hydrosilylation reaction catalyst used, and the like.

[0039] 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 crosslinkable composition may contain a non-reactive organopolysiloxane (including a linear or cyclic organopolysiloxane having a low viscosity of about 0.5 to 10 mPa·s at 25°C); an antioxidant such as a phenol, quinone, amine, phosphorus, phosphite, sulfur, or thioether; a light stabilizer such as a triazole or benzophenone; a flame retardant such as a phosphate ester, halogen, phosphorus, or antimony; one or more antistatic agents such as a cationic surfactant, anionic surfactant, or nonionic surfactant; a dye; a pigment, etc. The crosslinkable composition for forming silicone elastomer particles may or may not contain a component such as a silane for forming a silicone resin coating.

[0040] [Coating with Silicone Resin] The silicone resin-coated silicone elastomer particles of the present 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 comprises: i) R ３ SiO １／２ (R is a monovalent organic group) ２ SiO ２／２ (R is a monovalent organic group), and iii) a D siloxane unit represented by RSiO ３／２ (R is a monovalent organic group), and iv) SiO ４／２and one or more silicone resins selected from silicone resins consisting of a combination of two or more Q siloxane units represented by the following formula (however, silicone resins consisting only of T siloxane units are excluded).

[0041] In this embodiment, the silicone resin coating contains the above-mentioned silicone resin, which contributes to stress relaxation of the material to which it is added while maintaining dispersibility in the material to which it is added. More specifically, by coating part or all of the surface of the silicone elastomer particles with the silicone resin coating, secondary aggregation between particles is effectively suppressed, thereby improving dispersibility, handling, and compounding stability. Furthermore, the presence of the silicone resin coating also provides degradation resistance, meaning that the additive is less likely to affect the degradation of the material to which it is added over long-term use. Note that 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 be unable to fully utilize the properties of the silicone elastomer particles due to the T-siloxane units, and may be insufficient to improve thermal stress.

[0042] In this embodiment, the amount of silicone resin other than the above is preferably less than 5% by mass, more preferably less than 3% by mass, and particularly preferably less than 1% by mass, based on the total amount of silicone resin used in 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. Other silicone resins (e.g., RSiO ３／２

[0033] If the silicone resin-coated silicone elastomer particles contain a silsesquioxane resin represented by the formula (2), the resulting silicone resin-coated silicone elastomer particles may be prone to scattering or adhesion to containers during handling, or the problem of aggregation may not be sufficiently resolved, resulting in poor handling and workability and work efficiency. Furthermore, the silicone resin coating preferably contains less than 5% by mass of resins other than the silicone resin, based on the entire silicone resin coating, more preferably less than 3% by mass, and particularly preferably less than 1% by mass. Most preferably, no resins other than the silicone resin are intentionally added, and it is most preferred that no other silicone resins are contained on the surfaces of the silicone elastomer particles.

[0043] In this embodiment, the silicone resin contained in the silicone resin coating is not limited as long as it is a silicone resin composed of a combination of two or more types selected from the above i) M siloxane unit, ii) D siloxane unit, iii) T siloxane unit, and iv) Q siloxane unit. 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 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.

[0044] In this embodiment, the silicone resin coating may contain one or more silicone resins selected from silicone resins comprising iv) Q siloxane units and one or a combination of multiple types selected from i) to iii) M / D / T siloxane units. By including such silicone resins, it is possible to form a resin coating that efficiently forms three-dimensional crosslinks and suppresses aggregation. Examples of such silicone resins include: silicone resins comprising M siloxane units and Q siloxane units; silicone resins comprising D siloxane units and Q siloxane units; silicone resins comprising T siloxane units and Q siloxane units; silicone resins comprising siloxane units, T siloxane units, and Q siloxane units; silicone resins comprising M siloxane units and Q siloxane units; silicone resins comprising D siloxane units, T siloxane units, and Q siloxane units; and silicone resins comprising M siloxane units, D siloxane units, T siloxane units, and Q siloxane units.

[0045] In this embodiment, the silicone resin coating may contain one or more silicone resins selected from, for example, a silicone resin composed of ii) D siloxane units and iv) Q siloxane units, and a silicone resin composed of two types of units, i.e., the D siloxane units and iv) Q siloxane units, and a combination of one or two types selected from i) M siloxane units and iii) T siloxane units. By containing such a silicone resin, silanols generated by hydrolysis of Q units form a three-dimensional structure, increasing the reaction efficiency with silanols of M units, D units, and T units, thereby enabling efficient introduction of functional groups, reducing unreacted silane remaining in water, and suppressing aggregation. Examples of such silicone resins include silicone resins composed of D siloxane units and Q siloxane units, silicone resins composed of D siloxane units, T siloxane units and Q siloxane units, and silicone resins composed of M siloxane units, D siloxane units, T siloxane units and Q siloxane units.

[0046] In this embodiment, a DQ silicone resin composed of D siloxane units and Q siloxane units is preferred from the viewpoint of emulsion stability and reaction efficiency.

[0047] In the silicone resin-coated silicone elastomer particles of this embodiment, the silicone resin may have an epoxy group-containing hydrocarbon group in a siloxane unit selected from the siloxane units i) to iii) of the silicone resin. By having an epoxy group-containing hydrocarbon group in a siloxane unit selected from the siloxane units i) to iii), when the silicone resin-coated silicone elastomer particles are mixed with a material to which they are to be added, the epoxy groups of the silicone resin-coated silicone elastomer particles serve as reaction sites with the material, further improving adhesion to the resin. This prevents the particle from peeling at the interface with the resin when the added resin is subjected to external or internal impact or strain, allowing the impact or strain to be absorbed within the added elastomer particles. Furthermore, when the powder particles break, the internal stress is absorbed while the particles break, contributing to crack resistance and toughness. Furthermore, this improved adhesion effectively reduces the thermal expansion coefficient, molding shrinkage, or elastic modulus, contributing to stress relaxation in the material. Furthermore, due to the improved adhesion, the additive has excellent resistance to deterioration, meaning that the additive is less likely to affect the deterioration of the material to which it is added over a long period of use.

[0048] The siloxane unit having an epoxy group-containing hydrocarbon group in the siloxane unit is selected from i) to iii) the M, D, and T siloxane units (in other words, the monovalent organic group contained in the M, D, and T siloxane units is the epoxy group-containing hydrocarbon group). If the silicone resin is a DQ silicone resin, the D siloxane unit has the epoxy group-containing hydrocarbon group. If the silicone resin is a TQ silicone resin, the T siloxane unit may have the epoxy group-containing hydrocarbon group, and if the silicone resin is a DTQ silicone resin, the D or T siloxane unit may have the epoxy group-containing hydrocarbon group.

[0049] In the present embodiment, the epoxy group-containing organic group is not particularly limited, and examples thereof include an epoxy group, a glycidyl ether group, a glycidyl ester group, a glycidylamino group, and groups in which these groups are bonded to a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. More specifically, examples of the epoxy group-containing organic group include a 3-glycidoxypropyl group and an alicyclic epoxy group such as a (2-(3,4-epoxycyclohexyl)ethyl group.

[0050] In this embodiment, the epoxy equivalent of the silicone resin-coated silicone elastomer particles is not particularly limited, but from the viewpoint of compatibility with and adhesion to the material to which they are added, the epoxy equivalent of the particle surface is preferably 2,000 to 100,000 g / mol, and more preferably 3,000 to 50,000 g / mol. The epoxy equivalent is determined using potentiometric titration.

[0051] In this embodiment, the silicone resin coating is preferably R １ ２ SiO ２／２ (R １ are independently a D siloxane unit represented by 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 SiO ４／２ and a DQ silicone resin comprising a Q siloxane unit represented by the formula: １ ２ SiO ２／２ (R １ are independently a D siloxane unit represented by 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 R １ ３ SiO １／２ (R １ is the same as above), and SiO ４／２ and Q siloxane units represented by the formula: １２ SiO ２／２ (R １ are independently a D siloxane unit represented by 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 SiO ４／２ and a DQ silicone resin comprising a Q siloxane unit represented by the formula:

[0052] Furthermore, in the DQ silicone resin, the ratio by mass of D siloxane units to Q siloxane units is more preferably within the range of 8:2 to 0.8:9.2. Furthermore, in the DQ silicone resin, the ratio by mass of D siloxane units to Q siloxane units is even more preferably within the range of 7:3 to 5:5. Furthermore, in the DTQ silicone resin, the ratio by mass of D siloxane units to the total mass of T siloxane units and Q siloxane units is even 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. Furthermore, in the R １ ２ SiO ２／２ R of the D siloxane unit represented by １ may be an alkyl group or an aryl group not having an epoxy group, but R １ When R contains an epoxy group, one of R １ is an alkyl group or an aryl group having an epoxy group, the other R １ is more preferably an alkyl group or an aryl group that does not have an epoxy group. １ ３ SiO ２／２ R of the T siloxane unit represented by １ may be an alkyl group or an aryl group not having an epoxy group, but R １ When R contains an epoxy group, one R １ is an alkyl group or aryl group having an epoxy group, other R １is more preferably an alkyl group or aryl group that does not have an epoxy group. The D siloxane units that constitute the silicone resin form two siloxane bonds to form a linear siloxane bond, while the Q siloxane units form four siloxane bonds to form a highly branched network or reticulated siloxane bond. Therefore, when the amount of D siloxane units is within the above range, a large amount of a moderately flexible polydiorganosiloxane structure is contained in the silicone resin, which improves the smoothness, flexibility, and conformability of the silicone resin coating on the surface of the silicone elastomer particles and particularly effectively suppresses the formation of secondary aggregate particles.

[0053] The above silicone resin can be obtained by subjecting a silane compound that provides these siloxane units to a hydrolysis reaction or a dehydration / dealcoholization condensation reaction on the surface of silicone elastomer particles.

[0054] More specifically, the silicone resin is 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 hydrolyzable silane or a condensation reaction product thereof, RSi(OA) ３ (wherein R is 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 hydrolyzable silane or a condensation reaction product thereof, and Si(OA) ４ (wherein A independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group), or a condensation reaction product thereof. The condensation reaction product of the silane compound used for coating is preferably an oligomer or a mixture of oligomers having an average of 20-mer, 2-10-mer, or 2-8-mer, and may be, for example, tetraethoxysilane or its condensation reaction product, such as ethyl silicate, or a mixture thereof.

[0055] 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, for example, all of the R's may be methyl groups, or they may each be a different substituent. The silicone resin may contain the monovalent organic group exemplified above in the siloxane unit.

[0056] In the formula, "OA" is 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 give 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, OA is particularly preferably an alkoxy group having 1 to 4 carbon atoms.

[0057] The silicone resin coating in this embodiment preferably contains a silicone resin composed of a condensation reaction product of 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 some of the silanes in the triorganoalkoxysilanes, diorganodialkoxysilanes, and organotrialkoxysilanes contained therein may have an epoxy group-containing hydrocarbon group. Furthermore, the silicone resin coating in this embodiment contains a DQ silicone resin composed of a condensation reaction product of diorganodialkoxysilanes and tetraalkoxysilanes, and at least some of the silanes in the diorganodialkoxysilanes may have an epoxy group-containing hydrocarbon group. In particular, some or all of the tetraalkoxysilane may be a condensation reaction product (oligomer / oligomer mixture), or the condensation reaction product forming the DQ silicone resin may be a condensation reaction product of a combination of some or all of the condensation reaction product (oligomer / oligomer mixture) of the tetraalkoxysilane with a diorganodialkoxysilane, which is preferred. 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 reaction product of dimethyldimethoxysilane and tetraethoxysilane.

[0058] The coating of the surface of silicone elastomer particles using the condensation reaction product of hydrolyzable silane is not particularly limited, but may be obtained by hydrolyzing and condensing the hydrolyzable silane in water in the presence of the silicone elastomer particles and an alkaline substance, thereby coating the surface of the silicone elastomer particles with a silicone resin.The timing of adding the alkaline substance or acidic substance is arbitrary, but from the viewpoint of uniformly coating the surface of the silicone elastomer particles, it is preferable to emulsify the crosslinkable reactive silicone raw material and the 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 together with the hydrosilylation reaction of the crosslinkable reactive silicone.

[0059] Preferably, the hydrolyzable silane is added to the crosslinkable reactive silicone raw material that forms the silicone elastomer particles, and the mixture is emulsified in water while being uniformly mixed using a conventional agitator such as a propeller blade or flat blade.

[0060] In the above-described emulsified state, from the viewpoint of uniformly coating the surfaces of the silicone elastomer particles, the temperature of the aqueous reaction liquid containing the silicone elastomer particles and the alkaline substance is preferably 10 to 60°C, more preferably in the range of 10 to 40°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 the silicone resin. The reaction liquid is continued to be stirred until the desired coating reaction with the silicone resin is completed, and may be stirred at a temperature higher than the above temperature (for example, under heating to 40°C or higher) to complete the reaction.

[0061] 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.

[0062] The alkaline substance is not particularly limited, and examples thereof 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. Among these, ammonia is the most suitable because it can be easily removed from the resulting silicone microparticle powder by volatilization. As the ammonia, commercially available aqueous ammonia solutions can be used.

[0063] After the hydrolysis and condensation reaction, the silicone resin-coated silicone elastomer particles of the present embodiment obtained 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.In addition, as a pretreatment for this operation, the dispersion may be concentrated by methods such as thermal dehydration, filtration separation, centrifugation, and decantation, and if necessary, the dispersion may be washed with water.

[0064] 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 particularly preferably in the range of 5.0 to 30.0 parts by mass, per 100 parts by mass of the silicone elastomer particles. When the coating amount is equal to or greater than the lower limit, the silicone elastomer particles can be effectively coated with the silicone resin coating, and technical effects such as uniform dispersibility in materials such as organic resins can be effectively achieved. Furthermore, if the coating amount is too large, the amount of SiO in the silicone resin, in particular, can be reduced. ４／２ Q siloxane units represented by the formula: and RSiO ３／２

[0023] However, by keeping the coating amount below the upper limit, the elasticity and elastic properties inherent in the silicone elastomer particles are adequately maintained, and technical effects such as stress relaxation can be effectively achieved when the silicone elastomer particles are blended with materials such as organic resins.

[0065] When the JIS-E hardness is 20 or less, the amount of silicone resin coating is preferably in the range of 20.0 to 40.0 parts by mass, and more preferably in the range of 22.5 to 30 parts by mass, per 100 parts by mass of the silicone elastomer particles. Even when the particles have a JIS-E hardness of 20 or less, by setting the coating amount to 20.0 parts by mass or more, the silicone resin-coated silicone elastomer particles can maintain high dispersibility even when dried.

[0066] 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.

[0067] The amount of the silicone resin coating can be easily controlled by controlling the amount of the hydrolyzable silane that forms the silicone resin added to the crosslinkable composition for forming silicone elastomer particles.

[0068] [Coating State of Silicone Elastomer Particles with Silicone Resin] The silicone resin-coated silicone elastomer particles according to this embodiment can be produced by employing a suitable manufacturing process, particularly as described in the next section, such that the silicone elastomer particle surface is uniformly and smoothly coated with a silicone resin coating in which epoxy groups are dispersed on the surface, resulting in a coating state with very few protrusions or irregularities on the silicone resin surface. In particular, when spherical silicone elastomer particles are uniformly coated with the silicone resin coating, the smooth particle surface suppresses secondary aggregation between particles, suppressing an increase in secondary particle size, while reducing the occurrence of surface friction, thereby achieving stress relaxation and lubricity. In this embodiment, the silicone resin coating may cover only a portion of the surface of the silicone elastomer particles, but preferably covers the entire surface. "Coating a portion of the surface of the silicone elastomer particles" means that there may be exposed portions of the silicone elastomer particles that are not covered by the silicone resin coating.

[0069] [Formation of Silicone Resin-Coated Silicone Elastomer Particles] The method for producing silicone resin-coated silicone elastomer particles according to this embodiment comprises: Step (I): emulsifying in water a mixture containing: (a) an organopolysiloxane having at least two alkenyl groups containing 2 to 20 carbon atoms per molecule; (b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms per molecule; and (d) a silane-based compound; Step (II): curing the emulsion obtained in Step (I) in the presence of (c) a hydrosilylation reaction catalyst to obtain silicone elastomer particles; and Step (III): simultaneously with or after Step (II), coating part or all of the surfaces of the silicone elastomer particles with the (d) silane-based compound and, optionally, (e) a silicone resin containing a silane-based compound added during Step (III). This production method allows for the production of the silicone resin-coated silicone elastomer particles according to this embodiment.

[0070] The above components (a), (b), and (c) may be the same as those described above. When components (d) and (e) contain a hydrolyzable silane, the hydrolyzable silane may be the same as those described above.

[0071] 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, or 50 to 1,000 parts by mass, per 100 parts by mass of the crosslinkable composition. Also, it is preferable that the component (d) silane compound contains a hydrolyzable silane or a condensation product thereof.

[0072] To uniformly disperse the crosslinkable composition for forming silicone elastomer particles and the silane compound in water, it is preferable to use an emulsifier, such as a homomixer, paddle mixer, Henschel mixer, homodisper, colloid mill, propeller agitator, homogenizer, in-line continuous emulsifier, ultrasonic emulsifier, or vacuum kneader.

[0073] 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 allowed to stand at room temperature to cure the crosslinkable silicone elastomer composition in the aqueous dispersion, thereby preparing 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 or adding the aqueous dispersion to hot water.

[0074] 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 (e) a silane compound added optionally 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 by 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.

[0075] In step (III), the silane-based compound contained in the aqueous dispersion may be present in its entirety in the step of emulsifying in water (step (I)), or may be present in the system in multiple steps (steps (I) and (III)). That is, 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-based compound in multiple steps in this manner, the silanols contained in the silane-based compound added and reacted in the previous step are more likely to be uniformly present on the particle surface, which allows the silane-based compound present earlier to react with the silane-based compound added later to react efficiently, suppressing aggregation and increasing the amount of functional groups introduced. When the silane compound is added in multiple portions in this manner, the temperature when 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 the silane compound (e) is added in step (III), it is preferable that the silane compound (e) contains a hydrolyzable silane.

[0076] Furthermore, in step (III), a portion 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 in the silicone resin, such as oligomers (e.g., tetra-pentamers) formed by condensation of multiple hydrolyzable silane molecules. Examples of such silane compounds other than hydrolyzable silanes include oligomers formed by condensation of multiple molecules of tetraalkoxysilane, etc. The oligomer is preferably an oligomer or oligomer mixture having an average of 20-20, 2-10, or 2-8, and may be, for example, tetraethoxysilane or its condensation product, ethyl silicate, or a mixture thereof.

[0077] In this embodiment, the silicone resin-coated silicone elastomer particles produced may contain epoxy groups. In this case, in the production method of this embodiment, a silane compound having an epoxy group-containing hydrocarbon group (hereinafter also referred to as epoxy group-containing silane) may be included 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 may be present in the system when the surfaces of the silicone elastomer particles are coated with the silicone resin (step (III)), or may be present in the system in multiple stages (steps (I) and (III)). In other words, when a silane compound (e) is added in step (III), at least one of the silane compound (d) and the silane compound (e) may contain an epoxy group-containing carbon silane. Furthermore, when a silane compound (e) is not added, the silane compound (d) may contain an epoxy group-containing silane.

[0078] When a silane compound (e) is added in step (III), the silane compound (e) may contain an epoxy group-containing silane (the silane compound (d) may also contain an epoxy group-containing silane).

[0079] Furthermore, from the viewpoint of obtaining silicone resins including DQ silicone resins, it is preferable to use the following specific silanes as each silane compound: (d) The silane compound preferably contains a tetraalkoxysilane or a condensation product thereof (in other words, at least a tetraalkoxysilane or a condensation product thereof is present in the step of emulsifying in water (step (I))). In this case, the (d) silane compound may further contain a diorganodialkoxysilane (in other words, not only a tetraalkoxysilane or a condensation product thereof but also at least a diorganodialkoxysilane may be present in the step of emulsifying in water (step (I))), or the (e) silane compound may further contain a diorganodialkoxysilane (in other words, a tetraalkoxysilane or a condensation product thereof may be present in step (I) and a diorganodialkoxysilane may be added in step (III)).

[0080] Furthermore, when the silicone resin-coated silicone elastomer particles to be produced contain epoxy groups, the following silanes may be used as the silane compound, specifically, from the viewpoint of obtaining a silicone resin containing a DQ silicone resin having epoxy groups. (d) The silane compound preferably contains a tetraalkoxysilane or a condensation product thereof, and the epoxy group-containing silane preferably contains 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 silane compound (d) 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 but also at least a diorganodialkoxysilane or a condensation product thereof may be present). By doing so, 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.

[0081] By coating with the 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 an additive for aqueous paints or coating agents.

[0082] 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, crosslinking temperature, etc., of the silicone resin-coated silicone elastomer particles. To prevent secondary aggregation of the obtained microparticles, it is preferable to control the temperature of the silicone resin-coated silicone elastomer particles to be 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, a bag filter, etc.

[0083] [Crushing / classification 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 crushed 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 using mechanically crushing the silicone resin-coated silicone elastomer particles containing aggregates, it is possible to obtain uniform functional particles that do not contain coarse particles, and the dispersibility in materials such as various organic resins, stress relaxation properties, etc. can be improved.

[0084] [Average Primary Particle Diameter] The average primary particle diameter of the silicone resin-coated silicone elastomer particles of this embodiment is not particularly limited, 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 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.

[0085] [Advantages of producing silicone resin-coated silicone elastomer particles] When the silicone resin-coated silicone elastomer particles of this embodiment are obtained by the above-mentioned production 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 the size of aggregated particles over time are unlikely to occur. Furthermore, this production 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).

[0086] [Additives for organic resins, and 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 unlikely to scatter or adhere to containers during blending, making them extremely easy to handle and work with. Furthermore, the 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 used in electronic materials. Thus, although not particularly limited, examples of the present embodiment may include an organic resin additive containing the silicone resin-coated silicone elastomer particles of the present embodiment; an organic resin composition containing the silicone resin-coated silicone elastomer particles of the present embodiment; a curable organic resin composition containing the silicone resin-coated silicone elastomer particles of the present embodiment and a curable organic resin; and a paint or coating agent containing the silicone resin-coated silicone elastomer particles of the present embodiment. In the organic resin additive of the present embodiment, the organic resin may contain an epoxy resin. In the paint or coating agent of the present embodiment, the organic resin may contain an epoxy resin. In the curable organic resin composition of the present embodiment, the curable organic resin may contain an epoxy resin. Furthermore, the present embodiment may also provide a cured product obtained by curing the curable organic resin composition of the present embodiment; a semiconductor device containing the cured product of the present embodiment; and a method for manufacturing a semiconductor device including curing the curable organic resin composition of the present embodiment. The silicone resin-coated silicone elastomer particles of the present embodiment may be used in combination with a solid (particularly powder-like) or liquid (particularly modified silicone materials such as oil) organic resin additive.

[0087] The additive for organic resin, organic resin composition, curable organic resin composition, paint or coating agent, cured product, semiconductor device, and method for manufacturing a semiconductor device according to the present embodiment will be described in more detail below.

[0088] [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.

[0089] In this embodiment, the organic resin composition containing the organic resin may contain other optional components such as a curing agent, a curing accelerator, a filler, a photosensitizer, a higher fatty acid metal salt, an ester wax, and a plasticizer. Examples of the curing agent include organic acids such as carboxylic acids and sulfonic acids and their anhydrides; organic hydroxy compounds; organosilicon compounds having a silanol group, an alkoxy group, or a halogeno group; and primary or secondary amino compounds, and two or more of these may be combined. 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 these may be used in combination. In the case of epoxy resins, it is particularly preferable to include an amine-based curing agent.

[0090] The silicone resin-coated silicone elastomer particles of this embodiment may be incorporated as an additive into thermoplastic organic resins other than those described above, and may 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.

[0091] 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, particularly the thermal shock resistance after moisture absorption, tend to be reduced. 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 tend to be reduced.

[0092] 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 above-mentioned 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 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 will be described later, 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.

[0093] Furthermore, the organic resin composition and curable organic resin composition of this embodiment may be free of volatile solvents, depending on the application and optional selection. Specifically, in the organic resin composition and curable organic resin composition of this embodiment, the volatile solvent content 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 solids 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 this embodiment may be designed to be free of these volatile solvents depending on the application, making it particularly suitable for use as an encapsulant or the like in the manufacture of semiconductor devices.

[0094] 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 that are component (A), the following epoxy resin (B) (hereinafter also referred to as "component (B)"), a curing agent, a curing agent (C) (hereinafter also referred to as "component (C)"), and an inorganic filler (D) (hereinafter also referred to as "component (D)"). In one aspect, the organic resin composition according to this embodiment may also contain additives other than these components, as long as they do not impair the effects of the present invention.

[0095] <Component (B): Epoxy Resin> The composition of one aspect of this embodiment contains 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. Examples of epoxy resins include 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. One type of epoxy resin may be used alone, or two or more types may be used in combination.

[0096] 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 aromatics 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, bisphenolol 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.

[0097] 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 solids content of the composition. This allows the fluidity of the composition during molding to be appropriately set, improving filling properties. The content of the epoxy resin (B) is, for example, 15% by mass or less, preferably 10% by mass or less, more preferably 5% by mass or less, relative to 100% by mass of the total solids content of the composition. Typically, the thermal expansion coefficient of a resin is greater than that of the inorganic filler (D) described below. Therefore, it is believed that thermal shrinkage can be further reduced by relatively reducing the amount of the epoxy resin (B). In other words, it is believed that warpage of the substrate can be further reduced. The total solids content of the composition refers to the sum of all components contained in the composition of one aspect of this embodiment, excluding the solvent.

[0098] <Component (C): Curing Agent> The composition of one aspect of this embodiment contains a curing agent (C). The curing agent (C) is not particularly limited as long as it has the property of curing an epoxy resin. The curing agent (C) preferably contains a phenolic curing agent. Phenol-based curing agents are preferred in terms of the balance of flame resistance, moisture resistance, electrical properties, curability, storage stability, and the like. Phenol-based curing agents include monomers, oligomers, polymers, and the like having two or more phenolic hydroxyl groups in the molecule. The molecular weight, molecular structure, and the like 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.

[0099] 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-based curing agents. Specific examples of the amine-based curing agents include aliphatic polyamines and aromatic polyamines. Specific examples of the acid anhydride-based curing agents 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). Specific examples of the mercaptan-based curing agents include polymercaptan compounds such as polysulfides, thioesters, and thioethers. Specific examples of the catalyst-based 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 BF ３ The curing agent (B) may be used singly or in combination of two or more kinds.

[0100] The content of the curing agent (C) is, for example, 0.5% by mass or more, preferably 1% by mass or more, more preferably 1.5% by mass or more, based on 100% by mass of the total solid content of the composition. This provides excellent fluidity during molding, improving filling and moldability. The content of the curing agent (C) is, for example, 9% by mass or less, preferably 8% by mass or less, more preferably 7% by mass or less, based on 100% by mass of the total solid content of the composition. This can contribute to further suppressing warpage of the substrate.

[0101] <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. One type of filler (D) may be used alone, or two or more types may be used in combination. The particle shape is preferably as spherical as possible, and the filling amount can be increased by mixing particles of different sizes. Furthermore, from the viewpoint of heat dissipation, it is also possible to partially or completely replace silica with alumina, silicon nitride, aluminum nitride, boron nitride, etc. 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.

[0102] As described above, the filler (D) is typically particulate, and the particle shape may be, but is not limited to, a spherical shape. 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. Furthermore, by making the average particle size relatively small (e.g., 1 to 20 μm) and combining particles of different average particle sizes, it is possible to improve the filling ability into narrow gaps in cutting-edge wafer-level packages, for example. The average particle size of the filler (D) can be determined by acquiring volumetric particle size distribution data using a laser diffraction / scattering particle size distribution analyzer and processing the data. Measurement is typically performed wet.

[0103] 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. Furthermore, 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 described later in the section on coupling agent (E).

[0104] 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 solids content of the composition. By appropriately increasing the content of the filler (D), warpage of the chip or substrate can be further reduced. In addition, 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. Small thermal expansion change makes it easier to suppress deterioration of warpage. In addition, 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, relative to 100% by mass of the total solids content of the composition. By appropriately reducing the content of the filler (D), it is possible to suppress deterioration of moldability due to reduced fluidity during molding.

[0105] <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 containing 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.

[0106] Examples of the coupling agent (E) include known coupling agents such as epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane, alkenylsilane such as vinylsilane or hexenylsilane, various silane compounds such as acrylic silane and methacrylic silane, titanium compounds, aluminum chelates, and aluminum / zirconium compounds. The coupling agent (E) may be used alone or in combination of two or more. Also, known surface treatment agents such as silazane may be used in combination.

[0107] 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, based on the total mass of the filler (D) taken as 100% by mass. The content of the coupling agent (E) is, for example, 2.0% by mass or less, preferably 1.0% by mass or less, based on the total mass of the composition.

[0108] <Other Components> 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 these additives include those listed in Patent Document 2 (see paragraphs

[0070] to

[0075] ), WO 2024 / 202136 (

[0083] to

[0086] ), and WO 2021 / 149727 (

[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 interfere with the effects of the present invention, such as 0.1 to 5.0% by mass, preferably 0.1 to 3.0% by mass, and more preferably 0.2 to 1.5% by mass.

[0109] [Production Method, Method for Forming a 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 can be melt-kneaded using a kneader, heated rolls, or the like at a temperature preferably between 40°C and 130°C, and then cooled and solidified to produce 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, a powder / granular composition may be compressed into tablets. Furthermore, a sheet-like composition can be produced by placing the mixture of the composition on a pallet, cooling it, and then applying a press roll, roll rolling, or coating it with a solvent mixture to form 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 produce 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 is therefore suitable for use 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, or 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.

[0110] [Semiconductor Device and Manufacturing Method for Semiconductor Device] The cured product obtained by curing the curable organic resin composition of the present embodiment has properties such as 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., or as a build-up material for semiconductor device adhesives, adhesives, underfill agents, insulating materials, package substrates, etc. The curable resin composition of the present embodiment, particularly the curable epoxy resin composition (powder, tablet, granular, etc.), can be suitably used as a heat-melting encapsulant (B-stage material) for encapsulating semiconductor elements. The method for encapsulating semiconductor elements is not particularly limited, and can be performed by known methods such as ordinary transfer molding or compression molding. The semiconductor package to which the cured product of this embodiment can be applied is not particularly limited, and can be used to seal various semiconductor packages described in, for example, JP 2020-063338 A, JP 2019-085514 A, JP 2020-023643 A, etc.

[0111] The method for manufacturing a semiconductor device according to the present embodiment is not particularly limited as long as it includes a step of curing the composition according to the present embodiment at any stage in the manufacturing process of the semiconductor device. The method for manufacturing a semiconductor device according to the present embodiment may also include a step of encapsulating a semiconductor element with the cured product according to one aspect of the present embodiment.

[0112] For example, a laminate having a large number of semiconductor elements such as ICs mounted thereon is placed in a cavity of a mold, and then 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.

[0113] The molding conditions can be appropriately selected depending on the molding method, the curability of the curable resin composition, the mold temperature, and the like. As an example, the conditions for transfer molding using the curable epoxy resin composition of this embodiment can be appropriately set depending on the type of material in the composition of one aspect of this embodiment, the type of semiconductor device to be manufactured, and the like. Typically, the mold temperature is 170 to 180°C, and the molding time can be selected depending on the mold temperature and curability, but can generally be set to 10 to 600 seconds, or 30 to 120 seconds. Furthermore, after the initial curing, post-curing or heat treatment can be carried out for a period ranging from several seconds to several hours to complete the curing reaction.

[0114] Furthermore, a semiconductor device can be manufactured by flip-chip mounting using a sheet-shaped curable organic resin composition, for example, as follows: That is, the sheet-shaped composition is placed on the electrode surface side of a semiconductor element having bonding bumps or on the bump bonding side of a circuit board, and the semiconductor element and the circuit board are bump-bonded and adhesively sealed with a resin, thereby flip-chip mounting the semiconductor device.

[0115] Furthermore, since the silicone resin-coated silicone elastomer particles of this embodiment have an excellent stress relaxation effect when blended with an organic resin, they may be blended with epoxy resins for printed wiring boards to form prepregs, and further, copper foil with a filler particle-containing resin layer for printed wiring boards may be formed by providing a resin layer containing the silicone resin-coated silicone elastomer particles of this embodiment on one side of the copper foil, and used for copper-clad laminates (CCLs). Therefore, the cured product of this embodiment may be included in copper-clad laminates as semiconductor devices.

[0116] [Paints and Coating Agents] In the present embodiment, examples of paints and coating agents include room temperature curing types, room temperature drying types, and heat curing types, and depending on the properties, examples include water-based, oil-based, and powder-based paints. 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.

[0117] 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, but in order to impart a uniform and 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 above-mentioned lower limit, the matte finish, adhesion, stress relaxation properties, and other performance characteristics of the paint film may be insufficient, while if the amount exceeds the above-mentioned upper limit, the organic resin, paint, or coating agent may thicken after blending, reducing handling and workability.

[0118] The paint and coating agent of the present 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 polymer compounds, flame retardants, and weather resistance imparting agents.

[0119] [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 resistant to scattering and do not 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.

[0120] Although the present embodiment has been described above, the silicone resin-coated silicone elastomer particles of the present invention, the method for producing the same, and the additive for organic resins and other uses thereof 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, the method for producing the same, and the additive for organic resins and other uses thereof.

[0121] The silicone resin-coated silicone elastomer particles of the present invention and their production 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 values ​​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 a silicone cured product (cured silicone particles) and do not include emulsions.

[0122] <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.

[0123] [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. The hardness of this sheet was measured using a JIS-A hardness tester or a JIS-E hardness tester specified in JIS K 6253.

[0124] [Average Primary Particle Diameter of Silicone Elastomer Particles] The emulsion particles before the addition of the platinum catalyst were measured using a laser diffraction particle size distribution analyzer (such as an LS-230 from Beckman Coulter or a Mastersizer 3000 from Malvern), and the median diameter (the particle size corresponding to 50% of the cumulative distribution, or 50% particle size) was taken as the average 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 (such as a Mastersizer 3000 from Malvern). It has been confirmed that the median diameter (the particle size corresponding to 50% of the cumulative distribution, or D90, μm) of the cured silicone particles in ethanol and the average primary particle size based on the arithmetic dispersity (SD, μm2, indicating the degree of dispersion of the particle size distribution) are nearly identical to the average primary particle size based on the emulsion particle size measurement described above.

[0125] [Components for forming silicone elastomer particles] The average formulas of components (A) and (B) used in the examples and comparative examples are listed below. In the following formulas, Vi represents CH ２ =CH-, Me is a vinyl group ３ - represents a methyl group, and Hex represents a hexenyl group represented by CH2=CH-C4H8-. The alkenyl group content is determined by the ratio of the vinyl group (CH ２ =CH-) molecular weight ratio. [Chemical formula 1-1] Me ２ HexSiO-(Me ２ SiO) １１０ -(MeHexSiO) １．５ -SiHexMe ２ , the alkenyl group content is 1.0 mass %, and the viscosity is 420 mPa·s. [Chemical Formula 1-2] Me２ ViSiO-(Me ２ SiO) １５０ -SiViMe ２ The alkenyl group content is 0.47% by mass, and the viscosity is 350 mPa·s. [Chemical Formula 1-3] Me ２ HexSiO-(Me ２ SiO) ５７ -(MeHexSiO) ３ -SiHexMe ２ The alkenyl group content is 2.7% by mass, and the viscosity is 100 mPa·s. [Chemical Formula 1-4] Me ２ HexSiO-(Me ２ SiO) １３０ -(MeHexSiO) １５ -SiHexMe ２ The alkenyl group content is 4.0% by mass, and the viscosity is 500 mPa·s. 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. ２ HSiO-(Me ２ SiO) １４ -SiHMe ２ The silicon-bonded hydrogen atom content is 0.12% by mass, and the viscosity is 10 mPa·s. ２ HSiO-(Me ２ SiO) ６０ -SiHMe ２ The silicon-bonded hydrogen atom content is 0.039% by mass, and the viscosity is 70 mPa·s. [Chemical Formula 3-1] Dimethylpolysiloxane (XIAMETER manufactured by Dow-Toray Industries, Inc.) ＴＭ PMX-200 Silicone Fluid 100 cSt) Viscosity is 10 mPa·s.

[0126] [Example 1-1] 97.4 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-1] 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 30 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 4.2 μm. Subsequently, 380 parts by mass 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 with polyoxyethylene sorbitan laurate and pure water to form an aqueous dispersion, and the resulting mixture was stirred. The emulsion was then allowed to stand at 50°C for 1 hour to allow for a hydrosilylation reaction. The aqueous suspension was then cooled to 10-15°C, after which 60 parts by mass of 28% aqueous ammonia was added. The pH of the resulting solution 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 the mixture was stirred at this temperature for a total of 3 hours. The liquid temperature was then raised to 50°C, and the mixture was stirred for 5 hours to allow for a condensation reaction, resulting in the preparation of a uniform aqueous suspension of silicone rubber particles coated with silicone resin. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, Model: FJD-2B) to obtain 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.

[0127] [Example 1-2] 97.4 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-1] 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 a 25°C aqueous solution consisting of 1.4 parts by mass of polyoxyethylene sorbitan laurate, 0.2 parts by mass of polyoxyalkylene alkyl ester, and 30 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 4.2 μm. Then, 400 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 with polyoxyethylene sorbitan laurate and pure water to form an aqueous dispersion, and the resulting mixture was stirred. The emulsion was then allowed to stand at 50°C for 1 hour to allow for a hydrosilylation reaction. The aqueous suspension was then cooled to 10-15°C, after which 50 parts by mass of 28% aqueous ammonia was added. The pH of the resulting solution was 11. While cooling and stirring, 4.5 parts by mass of glycidoxypropyl(methyl)dimethoxysilane was slowly added dropwise over 20 minutes or more, and the mixture was stirred at this temperature for a total of 3 hours. The liquid temperature was then raised to 50°C, and the mixture was stirred for 5 hours to allow for a condensation reaction, resulting in the preparation of a uniform aqueous suspension of silicone rubber particles coated with silicone resin. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, Model: FJD-2B) to obtain 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.

[0128] [Example 1-3] 97.4 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-1] 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 1.4 parts by mass of polyoxyethylene sorbitan laurate, 0.2 parts by mass of polyoxyalkylene alkyl ester, and 20 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 3.6 μm. Then, 410 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 with polyoxyethylene sorbitan laurate and pure water to form an aqueous dispersion, and the resulting dispersion was stirred. The emulsion was then allowed to stand at 50°C for 1 hour to allow for a hydrosilylation reaction. The aqueous suspension was then cooled to 10-15°C, after which 50 parts by mass of 28% aqueous ammonia was added. The pH of the resulting solution 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 the mixture was stirred at this temperature for a total of 3 hours. The liquid temperature was then raised to 50°C, and the mixture was stirred for 5 hours to allow for a condensation reaction, resulting in the preparation of a uniform aqueous suspension of silicone rubber particles coated with silicone resin. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, Model: FJD-2B) to obtain 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.

[0129] [Example 1-4] 31 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-1], 29 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-3], and 40 parts by mass of a dimethylpolysiloxane represented by the average formula [Chemical Formula 3-1] 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 60 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 5.3 μm. Subsequently, 370 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 with polyoxyethylene sorbitan laurate and pure water to form an aqueous dispersion, and the resulting mixture was stirred. The emulsion was then allowed to stand at 50°C for 1 hour to allow for a hydrosilylation reaction. The aqueous suspension was then cooled to 10-15°C, after which 35 parts by mass of 28% aqueous ammonia was added. The pH of the resulting solution was 11. While cooling and stirring, 6.2 parts by mass of glycidoxypropyl(methyl)dimethoxysilane was slowly added dropwise over 20 minutes or more, and the mixture was stirred at this temperature for a total of 3 hours. The liquid temperature was then raised to 50°C, and the mixture was stirred for 5 hours to allow for a condensation reaction, resulting in the preparation of a uniform aqueous suspension of silicone rubber particles coated with silicone resin. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, Model: FJD-2B) to obtain silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 8 and a JIS-E hardness of 23.

[0130] [Example 1-5] 90.7 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-2], 0.4 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-1], and 8.9 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-2] were uniformly mixed at room temperature. 24.5 parts by mass of a condensation reaction product of tetraethoxysilane (an oligomer mixture with an average pentamer) and 10.5 parts by mass of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution at 25 °C consisting of 2.1 parts by mass of polyoxyethylene sorbitan laurate, 0.3 parts by mass of polyoxyalkylene alkyl ester, and 40 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 4.2 μm. Then, 680 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 with polyoxyethylene sorbitan laurate and pure water to form an aqueous dispersion, and the resulting dispersion was stirred. The emulsion was then allowed to stand at 50°C for 1 hour to allow for a hydrosilylation reaction. The aqueous suspension was then cooled to 10-15°C, after which 40 parts by mass of 28% aqueous ammonia was added. The pH of the resulting solution was 11. While cooling and stirring, 7.0 parts by mass of glycidoxypropyl(methyl)dimethoxysilane was slowly added dropwise over 20 minutes or more, and the mixture was stirred at this temperature for a total of 3 hours. The solution temperature was then raised to 50°C, and the mixture was stirred for 5 hours to allow for a condensation reaction, resulting in a uniform aqueous suspension of silicone rubber particles coated with silicone resin. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, Model: FJD-2B) to obtain silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of less than 8 and a JIS-E hardness of 7.

[0131] [Example 1-6] 88.2 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-2], 0.1 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-1], and 11.7 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 2-2] were uniformly mixed at room temperature. 24.5 parts by mass of a condensation reaction product of tetraethoxysilane (an oligomer mixture with an average pentamer) and 10.5 parts by mass of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution at 25 °C consisting of 2.1 parts by mass of polyoxyethylene sorbitan laurate, 0.3 parts by mass of polyoxyalkylene alkyl ester, and 40 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 3.9 μm. Subsequently, an emulsion was prepared by diluting with 630 parts by mass of pure water. 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 with polyoxyethylene sorbitan laurate and pure water to form an aqueous dispersion, and the resulting dispersion was stirred. The emulsion was then allowed to stand at 50°C for 1 hour to allow for a hydrosilylation reaction. The aqueous suspension was then cooled to 10-15°C, after which 30 parts by mass of 28% aqueous ammonia was added. The pH of the resulting solution was 11. While cooling and stirring, 7.0 parts by mass of glycidoxypropyl(methyl)dimethoxysilane was slowly added dropwise over 20 minutes or more, and the mixture was stirred at this temperature for a total of 3 hours. The liquid temperature was then raised to 50°C, and the mixture was stirred for 5 hours to allow for a condensation reaction, resulting in the preparation of a uniform aqueous suspension of silicone rubber particles coated with silicone resin. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, Model: FJD-2B) to obtain silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of less than 8 and a JIS-E hardness of 3.

[0132] [Example 1-7] 97.4 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-1] 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 mixture to prepare an 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.

[0133] [Comparative Example 1-1] 84 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-4] and 16 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 1.7 parts by mass of polyoxyethylene sorbitan laurate, 0.3 parts by mass of polyoxyalkylene alkyl ester, and 20 parts by mass of pure water, and further uniformly emulsified using a colloid mill. The average primary particle diameter was 2.1 μm. Subsequently, 370 parts by mass 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 with polyoxyethylene sorbitan laurate and pure water to form an aqueous dispersion, 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 rubber particles coated with a silicone resin. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, model number: 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.

[0134] [Comparative Example 1-2] 89.9 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-3] 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 size was 1.9 μm. Subsequently, 390 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 with polyoxyethylene sorbitan laurate and pure water to form an aqueous dispersion, and the resulting mixture was stirred. The emulsion was then allowed to stand at 50°C for 1 hour to allow for a hydrosilylation reaction. The aqueous suspension was then cooled to 10-15°C, after which 60 parts by mass of 28% aqueous ammonia was added. The pH of the resulting solution 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 the mixture was stirred at this temperature for a total of 3 hours. The liquid temperature was then raised to 50°C, and the mixture was stirred for 5 hours to allow for a condensation reaction, resulting in the preparation of a uniform aqueous suspension of silicone rubber particles coated with silicone resin. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, Model: FJD-2B) to obtain 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.

[0135] [Comparative Example 1-3] 89.9 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-3] 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 size 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 with polyoxyethylene sorbitan laurate and pure water to form an aqueous dispersion, 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 rubber particles coated with a silicone resin. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, model number: 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.

[0136] [Comparative Example 1-4] 89.9 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-3] 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 size 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 with polyoxyethylene sorbitan laurate and pure water to form an aqueous dispersion, and the resulting mixture was stirred. The emulsion was then allowed to stand at 50°C for 1 hour to allow for a hydrosilylation reaction. The aqueous suspension was then cooled to 10-15°C, after which 60 parts by mass of 28% aqueous ammonia was added. The pH of the resulting solution 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 the mixture was stirred at this temperature for a total of 3 hours. The liquid temperature was then raised to 50°C, and the mixture was stirred for 5 hours to allow for a condensation reaction, resulting in the preparation of a uniform aqueous suspension of silicone rubber particles coated with silicone resin. This aqueous suspension was then dried in an airflow dryer (Seishin Enterprise, Model: FJD-2B) to obtain 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.

[0137] [Comparative Example 1-5] 95.8 parts by mass of a polyorganosiloxane represented by the average formula [Chemical Formula 1-2] 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.

[0138]

[0139] <Preparation of Curable Organic Resin Composition> Each of the particles of Examples 1-1 to 1-7 and Comparative Examples 1-1 to 1-5 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.

[0140] Specifically, the curable organic resin composition was produced as follows. The components in the amounts (parts by mass) shown in Table 2 were mixed at room temperature using a mixer to obtain a mixture. 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.

[0141] Details of each raw material component are as follows: (Epoxy resins) Epoxy resin 1: Biphenyl type epoxy resin (Mitsubishi Chemical Corporation, product number: YX-4000H) Epoxy resin 2: Mixture of trisphenylmethane type epoxy resin (75% by mass) and biphenyl type epoxy resin (25% by mass) (Mitsubishi Chemical Corporation, product number: YL6677)

[0142] (Curing Agent) Curing Agent 1: Trisphenylmethane type phenolic resin (Air Water Inc., HE910-20)

[0143] (Inorganic fillers) 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)

[0144] (Curing accelerators) Curing accelerator 1: 2,3-dihydroxynaphthalene (Tokyo Chemical Industry Co., Ltd.) Curing accelerator 2: triphenylphosphine (Tokyo Chemical Industry Co., Ltd.)

[0145] (Coupling Agents) Coupling Agent 1: N-phenyl-3-aminopropyltrimethoxysilane (Dow-Toray Co., Ltd., Z-6883)

[0146] (Release Agent) Release Agent: Glycerin Trimontanate Ester (Clariant Japan Co., Ltd., Ricorb WE-4)

[0147] (Silicone Compound) Silicone Compound: As examples, the silicone elastomer particles of Examples 1-1 to 1-7 were used, and as comparative examples, the silicone elastomer particles of Comparative Examples 1-1 to 1-5 were used.

[0148]

[0149] <Preparation of Cured Products (Compression Molding)> Cured products were prepared using each of the curable organic resin compositions listed in Table 2 (Examples 2-1 to 2-7, Comparative Examples 2-1 to 2-6) prepared as described above. A mold consisting of upper, middle, and lower molds was used for molding. A mold cut out to a size of 100 mm x 10 mm x 4 mm or 50 mm x 50 mm x 1 mm was used as the middle mold. 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 under conditions of 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, a cured product for evaluation was prepared. Unless otherwise specified, test specimens were prepared under these conditions (compression molding).

[0150] <Evaluation of mechanical properties of cured product> The mechanical properties of the obtained cured product were evaluated. [Linear expansion coefficient of cured product] The linear expansion coefficient of a 4 mm x 4 mm x 10 mm cured product was measured using a thermomechanical analyzer (TMA7100, manufactured by Hitachi High-Tech Science Corporation). The measurement was carried out 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 0°C and 140°C was defined as CTE1. The obtained evaluation results are shown in Table 3.

[0151] [Flexural modulus, flexural strength and breaking energy of cured product] A cured product measuring 100 mm in length, 10 mm in width and 4 mm in thickness was measured for flexural modulus [MPa (N / mm ２ )], bending strength [MPa (N / mm ２ As a result of the above evaluations, the elastic modulus of the cured product of Example 2-1 was 14,300 MPa, and the elastic modulus of the cured product of Comparative Example 2-2 was 14,500 MPa.

[0152] [Izod impact test of cured product] Using a transfer molding machine, the curable resin compositions shown in Table 1 were injected into a mold cavity under the conditions of a mold temperature of 175°C, a molding pressure of 9.8 MPa, and a curing time of 3 minutes. Test pieces measuring 50 mm in length, 10 mm in width, and 4 mm in thickness were prepared without a notch, and the other conditions were measured in accordance with JIS K7110. The Izod strength [kJ / m ２ ) was evaluated.

[0153] [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 a cured product measuring 100 mm in length, 10 mm in width, and 4 mm in thickness. The obtained cured product was then subjected to a temperature cycle using hot and cold air in a test tank. A temperature cycle test was carried out up to 1,000 times under conditions of a low temperature of -40°C and a high temperature of 150°C, each with a holding time of 30 minutes. The obtained cured product had a bending strength [MPa (N / mm ２ ) ], breaking energy [mJ], Izod impact value [kJ / m ２ ) was evaluated. Furthermore, the flexural 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 by the initial values ​​before the temperature cycle were defined as the relative flexural strength, relative breaking energy, and relative Izod strength, respectively. The obtained evaluation results are shown in Tables 4 and 5.

[0154] [Molding Shrinkage] The shrinkage of the cured product obtained for each of the Examples and Comparative Examples was measured as follows. First, a transfer molding machine was used to produce a disk-shaped first test piece by injecting the curable resin composition shown in Table 1 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. Next, the first test piece was cooled to 25°C. Here, the shrinkage rate S was calculated from the inner diameter of the mold cavity at 175°C and the outer dimensions of the first test piece at 25°C as follows: １ (%) was calculated. 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 Next, the first test piece was post-cured in an oven at 175°C for 4 hours to prepare a second test piece. Next, the second test piece was cooled to 25°C. Here, the shrinkage rate S was calculated from the inner diameter dimension of the mold cavity at 175°C and the outer dimension of the second test piece at 25°C as follows: ２ (%) was calculated. ２ = {(inner diameter dimension of mold cavity at 175°C) - (outer diameter dimension of second test piece at 25°C)} / (inner diameter dimension of mold cavity at 175°C) × 100 The obtained evaluation results are shown in Table 6.

[0155]

[0156]

[0157]

[0158]

[0159] As shown in Table 3, in evaluations using curable resin compositions in which the hardness of the silicone elastomer particles was within the desired range (Examples 2-1 to 2-7), the CTE1 of the cured product obtained from the curable resin composition was reduced compared to curable resin compositions in which the hardness of the silicone elastomer particles was not within the desired range (Comparative Examples 2-1, 2-2, and 2-4) and a curable resin composition (2-3) that did not contain silicone elastomer particles. Furthermore, the modulus of elasticity of the cured product of Example 2-1 was improved or comparable to that of the cured product of Comparative Example 2-2. 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 Tables 4, 5, and 6, the hardness of the silicone elastomer particles was within the desired range, and the curable resin compositions (Examples) containing silicone elastomer particles with a silicone resin coating exhibited better test results for relative strength, relative energy, and relative Izod strength than curable resin compositions containing silicone elastomer particles without such a configuration, or curable resin compositions (Comparative Examples) that did not contain silicone elastomer particles. Furthermore, the mold shrinkage S1 and S2 were also reduced. This is thought to be because the silicone elastomer particles of the present invention have a shell structure (coating) on ​​the outside, allowing them to be uniformly dispersed within the resin composition without agglomeration, and the core portion of the particles is very flexible and highly conformable, effectively mitigating the effects of expansion and contraction on the resin matrix due to thermal history, thereby maintaining the elastic modulus and stress relaxation properties. 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 over long-term use.

[0160] The present invention can provide silicone resin-coated silicone elastomer particles that can contribute to stress relaxation of a material to which they are added while maintaining dispersibility in the material, and that also have deterioration resistance.The present invention can also provide an additive for organic resins, a paint or coating agent, a curable organic resin composition, a cured product, and a semiconductor device, which contain the silicone resin-coated silicone elastomer particles and are capable of reducing the thermal expansion coefficient, mold shrinkage rate, and elastic modulus, as well as a manufacturing method for manufacturing the semiconductor device.

Claims

1. Silicone resin-coated silicone elastomer particles comprising silicone elastomer particles and a silicone resin coating that coats part or all of the surface of the silicone elastomer particles, wherein the silicone elastomer particles in a state where they are not coated with the silicone resin coating have a JIS-A hardness of 45 or less and a JIS-E hardness of 1 or more, measured after curing a crosslinkable composition for forming silicone elastomer particles into a sheet, and 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, and the silicone resin coating has the following characteristics: i) R ３ SiO １／２ (R is a monovalent organic group) ２ SiO ２／２ (R is a monovalent organic group), and iii) a D siloxane unit represented by RSiO ３／２ (R is a monovalent organic group), and iv) SiO ４／２ and (iii) a silicone resin-coated silicone elastomer particle comprising one or more silicone resins selected from the group consisting of a combination of two or more types of Q siloxane units represented by the formula:

2. The silicone resin-coated silicone elastomer particles according to claim 1, wherein the silicone resin coating comprises one or more silicone resins selected from the group consisting of the Q siloxane unit of iv) and one or a combination of multiple M / D / T siloxane units of i) to iii).

3. The silicone resin-coated silicone elastomer particles according to claim 1, wherein the silicone resin coating comprises one or more silicone resins selected from the group consisting of a silicone resin consisting of the D siloxane unit of ii) and the Q siloxane unit of iv), and a silicone resin consisting of a combination of two types of units, the D siloxane unit of ii) and the Q siloxane unit of iv), and one or two types of units selected from the M siloxane unit of i) and the T siloxane unit of iii).

4. The silicone resin-coated silicone elastomer particles according to claim 1, wherein the average primary particle size measured by laser diffraction scattering is 0.1 to 100 μm.

5. The silicone resin coating is R １ ２ SiO ２／２ (R １ are independently a D siloxane unit represented by 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 SiO ４／２ and a Q siloxane unit represented by the following formula (1): wherein the molar ratio of the D siloxane unit to the Q siloxane unit is within the range of 8:2 to 0.8:9.

2.

6. The silicone resin-coated silicone elastomer particles according to claim 1, having a silicon-bonded hydrogen content per unit mass of 300 ppm or less.

7. The silicone resin-coated silicone elastomer particles according to claim 1, wherein the crosslinkable composition for forming the silicone elastomer particles before curing, for the silicone elastomer particles in a state not coated with the silicone resin coating, comprises: (a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms per molecule; (b) an organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms per molecule; and (c) a hydrosilylation reaction catalyst, wherein the molar ratio of the content of alkenyl groups (Alk (mol)) in component (a) to the content of hydrogen atoms bonded to silicon atoms (H (mol)) in component (b) is in the range of H / Alk = 0.5 to 1.

5.

8. An additive for organic resins, comprising the silicone resin-coated silicone elastomer particles according to any one of claims 1 to 7.

9. The organic resin additive of claim 8, wherein the organic resin comprises an epoxy resin.

10. A paint or coating agent comprising the silicone resin-coated silicone elastomer particles according to any one of claims 1 to 7.

11. The paint or coating of claim 10, wherein the organic resin comprises an epoxy resin.

12. A curable organic resin composition comprising the silicone resin-coated silicone elastomer particles according to any one of claims 1 to 7 and a curable organic resin.

13. The curable resin composition of claim 12, wherein the curable organic resin comprises an epoxy resin.

14. A cured product obtained by curing the curable organic resin composition according to claim 12.

15. A semiconductor device comprising the cured product according to claim 14.

16. A method for manufacturing a semiconductor device, comprising curing the curable organic resin composition according to claim 12.

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