JP7193218B2 - Method for producing silicone resin-coated silicone elastomer particles - Google Patents

Description

The present invention relates to a method for producing silicone resin-coated silicone elastomer particles whose surfaces are coated with a silicone resin.

Silicone elastomer particles are used as modifying additives for cosmetics, paints, inks, thermosetting organic resins, thermoplastic organic resins, etc. In particular, they are used as internal stress relieving agents for thermosetting organic resins and for organic resin films. is suitably used as a surface lubricant for In particular, silicone elastomer particles are excellent in heat resistance and flexibility derived from the elastomer skeleton. It is particularly suitable as an agent.

On the other hand, silicone elastomer particles are easily electrified, and when added to the above thermosetting organic resin, they tend to aggregate and are poor in uniform dispersibility in the resin. may be insufficient. For this reason, Patent Documents 1 to 4 (especially Patent Document 3) disclose that the surfaces of silicone particles are coated with a silicone resin composed of silsesquioxane units represented by SiO _3/2 , and dispersed in an organic resin. Silicone composite particles with improved properties, etc., and their uses as internal stress relieving agents or cosmetic compositions have been proposed. However, these silicone composite particles have improved dispersibility in organic resins and stress relaxation properties compared to the case where silicone elastomer particles are blended alone. Since the surface is coated, it is likely to scatter and adhere to the container (including the inner bag made of organic resin such as vinyl), which may deteriorate handling workability. Furthermore, there is still room for improvement in terms of oil absorbency, etc., and further improvements in the feel of the raw material for cosmetics have been demanded.

Furthermore, in Patent Documents 5 to 7, the present applicant et al. have disclosed a core-shell type crosslinked silicone obtained by coating the surface of crosslinkable silicone particles with a silicon compound (siloxane, silane, etc.) having a silicon-bonded hydrolyzable group. Particles, etc. are proposed. However, even the silicone resin-coated crosslinked silicone particles described in these documents cannot sufficiently solve the above-mentioned problems caused by aggregation of primary particles, and their performance and industrial production efficiency still have room for improvement. had left.

In particular, the silicone composite particles and the silicone resin-coated crosslinked silicone particles according to these documents are coated with a silicone resin such as silsesquioxane after synthesis of the silicone particles, and thus require multistage preparation using a plurality of containers. A manufacturing process is required, and there is a strong demand for a method for manufacturing silicone resin-coated crosslinked silicone particles that is excellent in industrial production efficiency.

JP 2010-132878 A JP 2011-105663 A JP 2011-168634 A JP 2011-102354 A JP 2003-226812 A International Patent Publication WO2006/098334 International patent application number PCT/JP2018/46703

Electron micrograph of silicone resin-coated silicone elastomer particles of Example 1 Electron micrograph of silicone resin-coated silicone elastomer particles of Comparative Example 4

An object of the present invention is to provide a method for producing silicone resin-coated silicone elastomer particles that can be easily produced on an industrial scale and that has a simple and convenient production process. A further object of the present invention is to provide the silicone resin-coated silicone elastomer particles with uses such as organic resin additives and raw materials for cosmetics.

In order to solve the above problems, as a result of intensive studies, the present inventors have found (a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule, and (b) a silicon-bonded hydrogen atom. A mixture comprising at least two in-molecular organohydrogenpolysiloxanes and (d) a hydrolyzable silane is emulsified in water and (c) cured in the presence of a hydrosilylation reaction catalyst to form spherical silicone elastomer particles. Simultaneously or after forming spherical silicone elastomer particles, the surfaces of the silicone elastomer particles are coated with (d) a silicone resin that is a condensation reaction product of a hydrolyzable silane. , found that the above problems can be solved, and arrived at the present invention.

The present inventors have also found that the above-mentioned problems can be solved by a method for producing organic resin additives, cosmetic raw materials, etc., including the above-mentioned process for producing silicone resin-coated silicone elastomer particles, and have completed the present invention.

That is, the object of the present invention is
[1] Achieved by a method for producing silicone resin-coated silicone elastomer particles, comprising the following steps (I), (II) and (III).
Step (I):
(a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule;
Step (II) of emulsifying a mixture containing (b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule and (c) a hydrolyzable silane in water:
Step (III) of curing the emulsion obtained in step (I) in the presence of (d) a hydrosilylation reaction catalyst to obtain spherical silicone elastomer particles:
Simultaneously with step (II) or after step (II), the step of coating the surface of the silicone elastomer particles with (c) a silicone resin that is a condensation reaction product of a hydrolyzable silane.

Preferably, the objects of the present invention are achieved by the following method for producing silicone resin-coated silicone elastomer particles.
[2] The (c) hydrolyzable silane in the above step (I) is
(c1) hydrolysis represented by R ₂ Si(OA) ₂ (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); silane,
a hydrolyzable silane represented by 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), and Si A mixture of two or more hydrolyzable silanes selected from hydrolyzable silanes represented by (OA) ₄ (wherein A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group) , or (c2) hydrolysis represented by 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) The method for producing silicone resin-coated silicone elastomer particles according to [1], which is a silane.
[3] The (c) hydrolyzable silane in the above step (I) is
(c1-1) R ¹ ₂ Si(OA) ₂ (wherein R ¹ is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or a phenyl group), and
A hydrolyzable silane represented by Si(OA) ₄ (wherein A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group) at a substance amount ratio of 8:2 to 3:7. The method for producing silicone resin-coated silicone elastomer particles according to [1] or [2], which is a mixture of hydrolyzable silanes.
[4] The molar ratio of alkenyl group content (Alk) in component (a) to silicon-bonded hydrogen atom content (H) in component (b) is H/Alk = 0.7 to 1.5
The method for producing silicone resin-coated silicone elastomer particles according to any one of [1] to [3], wherein the range is
[5] Any one of [1] to [4], further comprising a step of removing water from the aqueous dispersion containing the silicone resin-coated silicone elastomer particles (including aggregates) obtained in step (III). 10. A method for producing the silicone resin-coated silicone elastomer particles according to the above item.
[6] Furthermore, the silicone resin-coated silicone elastomer particles (including agglomerates) obtained in step (III) are crushed using mechanical means to obtain an average primary particle size of 0 as measured by a laser diffraction scattering method. The method for producing silicone resin-coated silicone elastomer particles according to any one of [1] to [5], comprising the step of obtaining silicone resin-coated silicone elastomer particles having a particle size of 5 to 20 μm.
[7] A method for producing an organic resin additive, including the method for producing the silicone resin-coated silicone elastomer particles according to any one of [1] to [6].
[8] A method for producing a raw material for a paint or a coating agent, comprising the method for producing the silicone resin-coated silicone elastomer particles according to any one of [1] to [6].
[9] A method for producing a cosmetic raw material, comprising the method for producing the silicone resin-coated silicone elastomer particles of any one of [1] to [6].

The method for producing silicone resin-coated silicone elastomer particles according to the present invention can be easily carried out on an industrial scale, is simple and has a short cycle time, and is therefore extremely efficient in production. Furthermore, the silicone resin-coated silicone elastomer particles obtained by the production method of the present invention are excellent in dispersibility and oil absorption in curable organic resins such as epoxy resins, and are more prone to secondary aggregation than conventional silicone elastomer particles. Since it is excellent in handling workability due to its low vol. Furthermore, the cosmetic composition containing the silicone resin-coated silicone elastomer particles according to the present invention can provide a cosmetic with excellent usability.

The method for producing the silicone resin-coated silicone elastomer particles of the present invention and the like will be described in detail below.

[Formation of silicone resin-coated silicone elastomer particles]
The method for producing silicone resin-coated silicone elastomer particles according to the present invention comprises (a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule;
A mixture containing (b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule and (d) a hydrolyzable silane is emulsified in water, and (c) in the presence of a hydrosilylation reaction catalyst. to obtain spherical silicone elastomer particles, and at the same time or after forming spherical silicone elastomer particles, the surfaces of the silicone elastomer particles are coated with (d) a silicone resin that is a condensation reaction product of a hydrolyzable silane. method. Details of the silicone elastomer particles themselves, the crosslinkable composition for forming the silicone elastomer particles, and details of the hydrolyzable silane will be described later.

Specifically, the method for producing silicone resin-coated silicone elastomer particles according to the present invention comprises:
It can be preferably obtained by a production method including the following steps (I), (II) and (III).
Step (I):
(a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule;
Step (II) of emulsifying a mixture containing (b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule and (d) a hydrolyzable silane in water:
Step (III) of curing the emulsion obtained in step (I) in the presence of (c) a hydrosilylation reaction catalyst to obtain spherical silicone elastomer particles:
Simultaneously with step (II) or after step (II), the step of coating the surface of the silicone elastomer particles with (d) a silicone resin that is a condensation reaction product of a hydrolyzable silane.

In the above method, a mixture containing component (a), component (b) and hydrolyzable silane (d), which are constituent components of the crosslinkable composition for forming silicone elastomer particles, is emulsified in an aqueous surfactant solution. After or during curing, silicone resin-coated silicone elastomer particles in which the surfaces of the silicone elastomer particles are coated with a silicone resin can be obtained. In addition, the particle size can be easily adjusted by adjusting the emulsion particle size. Nonionic surfactants, anionic surfactants, cationic surfactants, and betaine surfactants are exemplified. The particle size of the resulting silicone elastomer particles varies depending on the type and content of the surfactant. In order to prepare silicone elastomer particles with a small particle size, the amount of the surfactant added is preferably in the range of 0.5 to 50 parts by weight per 100 parts by weight of the crosslinkable composition. On the other hand, in order to prepare silicone elastomer particles having a large particle size, the amount of the surfactant added is preferably in the range of 0.1 to 10 parts by weight per 100 parts by weight of the crosslinkable composition. The amount of water added as a dispersion medium is preferably in the range of 20 to 1,500 parts by mass and 50 to 1,000 parts by mass with respect to 100 parts by mass of the crosslinkable composition.

An emulsifier is preferably used to uniformly disperse the crosslinkable composition for forming silicone elastomer particles and the hydrolyzable silane in water. Examples of the emulsifier include a homomixer, a paddle mixer, a Henschel mixer, a homodisper, a colloid mill, a propeller stirrer, a homogenizer, an in-line continuous emulsifier, an ultrasonic emulsifier, and a vacuum kneader.

Next, the aqueous dispersion of the hydrolyzable silane-containing crosslinkable composition for forming silicone elastomer particles prepared by the above method is heated or allowed to stand at room temperature to obtain a crosslinkable silicone elastomer in the aqueous dispersion. The composition can be cured to prepare 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, more preferably 10 to 95°C. Methods of heating the aqueous dispersion of the crosslinkable silicone elastomer composition include, for example, a method of directly heating the aqueous dispersion and a method of adding the aqueous dispersion to hot water.

Furthermore, along with the formation of the aqueous dispersion of the silicone elastomer particles, or after the formation of the aqueous dispersion of the silicone elastomer particles, the hydrolytic condensation reaction of the hydrolyzable silane contained in the aqueous dispersion causes the surface of the silicone elastomer particles to can be coated with a silicone resin. The conditions for coating with the silicone resin will be described later.

By coating with the above silicone resin, an aqueous dispersion of silicone resin-coated silicone elastomer particles can be obtained. The water-based dispersion is stable at room temperature and can be used as it is as a raw material for cosmetics and as an additive for water-based paints and coating agents.

Furthermore, silicone resin-coated silicone elastomer particles can be prepared by removing water from an aqueous dispersion of silicone resin-coated silicone elastomer particles. Examples of methods for removing water from the aqueous dispersion include drying using a vacuum dryer, a hot air circulation oven, and a spray dryer. The heating/drying temperature of the spray dryer should be appropriately set based on the heat resistance, cross-linking temperature, etc. of the silicone resin-coated silicone elastomer particles. In order to prevent secondary agglomeration of the fine particles obtained, it is preferable to control the temperature of the silicone resin-coated silicone elastomer particles below the glass transition temperature of the silicone resin coating the surface thereof. The silicone elastomer particles obtained in this manner can be recovered by a cyclone, bag filter or the like.

[Crushing/classification operation]
The method for producing the silicone resin-coated silicone elastomer particles of the present invention is the above method. It may and preferably has a step of pulverizing using a mechanical force with a pulverizer such as. Furthermore, it may be classified using a sieve so as to have a specific particle size or less. In particular, by crushing silicone resin-coated silicone elastomer particles containing agglomerates using mechanical force before use, uniform functional particles containing no coarse particles can be obtained, and dispersibility in various organic resins is possible. , stress relaxation properties, feeling of use when blended in cosmetics, etc. are improved.

[Average primary particle size]
In the method for producing the silicone resin-coated silicone elastomer particles of the present invention, the average primary particle size is not particularly limited. The average primary particle size measured by a method is preferably 0.5 to 20 μm, more preferably 0.5 to 15 μm. The particle size of the silicone resin-coated silicone elastomer particles is controlled according to the silicone elastomer particles before coating, the amount of coating, and the crushing/classifying process described above.

[Advantages in Manufacturing Silicone Resin-Coated Silicone Elastomer Particles]
When the silicone resin-coated silicone elastomer particles of the present invention are obtained by the above-described production method, the surface of the silicone elastomer particles is uniformly and smoothly coated with the silicone resin, and the secondary aggregation of the silicone resin-coated silicone elastomer particles is effective. , and the problem of handling workability such as an increase in aggregate particle size over time is less likely to occur. Further, the manufacturing method emulsifies a mixture containing a crosslinkable composition for forming silicone elastomer particles and a hydrolyzable silane to form an aqueous dispersion, and performs the curing reaction and the surface coating with the silicone resin in the same container (i.e., one pod). ), compared to the conventional method for producing silicone resin-coated silicone elastomer particles in which the silicone elastomer particles before coating are isolated to form a reaction solution, and the hydrolyzable silane is added dropwise into the reaction solution, the time is short and There is an advantage that production can be carried out with high efficiency.

The silicone resin-coated silicone elastomer particles according to the production method of the present invention are partially or entirely coated with a silicone resin. Preferably, D siloxane units represented by R ₂ SiO _2/2 (R is a monovalent organic group), T siloxane units represented by RSiO _3/2 (R is a monovalent organic group) and SiO _4/2 A silicone resin consisting of two types of siloxane units selected from Q siloxane units represented by (i.e., DQ, DT and TQ silicone resins) or RSiO _3/2 (R is a monovalent organic group) T siloxane units represented by (also referred to as silsesquioxane), and has a structure in which at least two silicon atoms in the silicone elastomer particles are crosslinked by silalkylene groups having 2 to 20 carbon atoms. Hereinafter, the term "silicone elastomer particles" simply refers to silicone elastomer particles before they are coated or compounded with a silicone resin.

[Silicone elastomer particles before coating]
First, silicone elastomer particles have a structure in which at least two silicon atoms are crosslinked by silalkylene groups having 2 to 20 carbon atoms. Such a silalkylene crosslinked structure is preferably formed by a hydrosilylation reaction of an alkenyl group having 2 to 20 carbon atoms and a silicon-bonded hydrogen atom between different siloxane molecules. In the present invention, the silalkylene group that bridges between the silicon atoms in the siloxane constituting the silicone elastomer particles and other silicon atoms is preferably a silalkylene group having 2 to 16 carbon atoms. A range of 8 is more preferred, and an ethylene group, propylene group, butylene group or hexylene group is particularly preferred.

The silicone elastomer particles according to the present invention are not particularly limited in terms of the average primary particle size before being coated with a silicone resin. It is preferable that the average primary particle size measured by a diffraction scattering method is 0.4 to 19 μm. Such silicone elastomer particles are further coated with a silicone resin composed of siloxane units represented by SiO _4/2 on the surface, further classified if necessary, and finally averaged by laser diffraction scattering method It provides silicone resin-coated silicone elastomer particles having a primary particle size of 0.5 to 20 μm. Needless to say, after coating, the average primary particle size of the particles is larger than that of the silicone elastomer particles before coating.

Examples of the shape of the silicone elastomer particles according to the present invention include spherical, spherical, elliptical, and irregular shapes, with spherical and spherical shapes being particularly preferred. In the present invention, by emulsifying a hydrolyzable silane together with a crosslinkable silicone raw material, an aqueous suspension containing spherical silicone elastomer particles coated with a silicone resin can be obtained in one reaction vessel. Since spherical silicone resin-coated silicone elastomer particles can be directly produced by drying the water-based suspension using a vacuum dryer, a hot air circulation oven, or a spray dryer, uncoated silicone elastomer particles can be prepared separately. It does not necessarily have to be manufactured and coated on its surface.

The silicone elastomer particles according to the present invention are elastomer particles having elasticity from the standpoint of feeling of use as a raw material for cosmetics, and technical effects such as stress relaxation and stickiness prevention when blended with organic resins. When the crosslinkable composition for forming silicone elastomer particles before curing is cured into a sheet, the hardness is preferably in the range of 10 to 80 as measured by a JIS A hardness tester defined in JIS K6301. When the JIS-A hardness of the rubber sheet measured by curing the crosslinkable composition for forming silicone elastomer particles into a sheet is within the above range, the resulting silicone elastomer particles have sufficiently suppressed cohesion and flowability. It tends to be rich in elasticity, dispersibility, smoothness, smoothness, and soft touch, and by selecting the above JIS-A hardness, it is possible to improve stress relaxation when blended with organic resin. Moreover, it is excellent in handling workability after coating with the silicone resin. Furthermore, the feeling of use of the cosmetic composition containing the particles coated with the silicone resin can be improved. When the silicone resin-coated silicone elastomer particles according to the present invention are used as an organic resin stress relaxation agent, the JIS-A hardness of the silicone elastomer particles should be in the range of 30 to 80, particularly 50 to 80. is particularly preferred.

The silicone elastomer particles according to the present invention may further have a silicon-bonded hydrogen content of 300 ppm or less per unit mass. The content of silicon-bonded hydrogen is preferably 250 ppm or less, more preferably 200 ppm or less. More preferably, it is 150 ppm or less, preferably 100 ppm or less, 50 ppm or less, and even more preferably 20 ppm or less. In the silicone elastomer particles according to the present invention, when the amount of silicon-bonded hydrogen increases, the cross-linking reaction proceeds with the reactive functional groups remaining in other silicone elastomer particles, and over time the silicone elastomer particles or the silicone resin-coated silicone This will result in agglomeration of the elastomer particles. Furthermore, in the present invention, by reducing the silicon atom-bonded hydrogen in the silicone elastomer particles, the generation of combustible hydrogen gas over time during storage of these particles is suppressed, leading to expansion of the container and ignition. There is an advantage that the obtained silicone resin-coated silicone elastomer particles can be safely handled in organic resin additives and other uses without causing problems such as the above.

A representative method for measuring silicon-bonded hydrogen in silicone elastomer particles is to use gas chromatography (headspace method) in contact with an alkali. For example, to the silicone elastomer particles, an ethanol solution of 40% concentration of potassium hydroxide is added in an equal amount to the unit mass and allowed to stand still for 1 hour. It can be identified by quantification by space gas chromatography.

[Crosslinkable composition for forming silicone elastomer particles]
The above silicone elastomer particles have a structure in which at least two silicon atoms are crosslinked by a silalkylene group having 4 to 20 carbon atoms in the molecule, and a crosslinkable composition containing the following components is subjected to a hydrosilylation reaction. It can be obtained by curing.
(a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule;
(b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule, and (c) a hydrosilylation reaction catalyst

Component (a) is an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule, and its structure is not particularly limited, and may be linear, cyclic, network, or partially branched linear. Although it may be one or more types of structures selected from the shape, a straight-chain organopolysiloxane is particularly preferable. Further, the viscosity of component (a) is preferably within a viscosity range that allows the above crosslinkable composition to be dispersed in water or that allows dispersion with a spray dryer or the like. Specifically, at 25° C., it is preferably in the range of 20 to 100,000 mPa·s, particularly preferably in the range of 20 to 10,000 mPa·s.

From the standpoint of oil absorption and dispersibility of the silicone elastomer particles, the content of dimethylsiloxane units represented by the formula: -(CH ₃ ) ₂ SiO- in component (a) is equal to all siloxane units other than the terminal siloxane units. It is preferably a straight-chain organopolysiloxane that accounts for 90 mol % or more of the Similarly, from the viewpoint of improving the oil absorption of the obtained silicone elastomer particles and improving the contact failure of electronic parts and the like provided with resin parts after blending, from component (a) to low polymerization degree (polymerization degree 3 to 20) cyclic or chain It is also preferable to remove the organopolysiloxane in advance by stripping or the like.

The alkenyl group having 2 to 20 carbon atoms in component (a) includes vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, nonenyl group, decenyl group, undecenyl group, dodecenyl group, Tridecenyl group, tetradecenyl group, pentadecenyl group, hexadecenyl group, heptadecenyl group, octadecenyl group, nonadecenyl group and icosenyl group are exemplified. From the viewpoint of reactivity and cohesiveness, the number of carbon atoms in the alkenyl group is preferably in the range of 2 to 16, preferably in the range of 2 to 8, and the use of a vinyl group or a hexenyl group is particularly preferred. The alkenyl group is preferably present at the molecular chain terminal of the organopolysiloxane, but may be present in the side chain or both. Examples of silicon-bonded groups other than alkenyl groups include alkyl groups such as methyl group, ethyl group, propyl group and butyl group; cycloalkyl groups such as cyclopentyl group and cyclohexyl group; phenyl group, tolyl group; Aryl groups such as xylyl group; aralkyl groups such as benzyl group, phenethyl group and 3-phenylpropyl group; unsubstituted or halogenated alkyl groups such as 3-chloropropyl group and 3,3,3-trifluoropropyl group; Substituted monovalent hydrocarbon groups are exemplified.

Component (a) is preferably a linear organopolysiloxane represented by the following chemical formula (1).

In formula (1), each R ¹¹ is independently an unsubstituted or halogen-substituted alkyl group having 1 to 20 carbon atoms (e.g., methyl group), an aryl group having 6 to 22 carbon atoms ( For example, a phenyl group, etc.) or a hydroxyl group, industrially preferably a methyl group or a phenyl group. R ^a is an alkenyl group having 2 to 20 carbon atoms, particularly preferably a vinyl group or a hexenyl group. R is a group represented by R ¹¹ or R ^a . m is a number of 0 or more, and n is a number of 1 or more. However, m, n and R are such that the content of the vinyl (CH ₂ ═CH—) moiety in the alkenyl group having 2 to 12 carbon atoms in the organopolysiloxane molecule represented by the above formula (1) is 0.00. It is a number that gives 5 to 3.0% by mass, and a number that gives component (a) a viscosity of 20 to 10,000 mPa·s at 25°C.

（式（２）中、ｍ１は０以上の数でありｎ１は各々正の数であり、ｍ１は式（２）で表される分子中のヘキセニル基（－（ＣＨ_２）_４ＣＨ＝ＣＨ_２）中のビニル（CH₂=CH-）部分の含有量が０．５～３．０質量％の範囲、より好ましくは１．０～２．０質量％の範囲となる数である。また、ｍ１＋ｎ１は、式（２）で表されるオルガノポリシロキサンの２５℃における粘度が２０ｍＰａ・ｓ以上となる範囲の数であり、より好適には、１００～５００ｍＰａ・ｓとなる数である。） Component (a) may be an organopolysiloxane having hexenyl groups at both ends of the molecular chain and side chains represented by the following structural formula (2), and part or all of the hexenyl groups of structural formula (2) may be an organopolysiloxane in which is a vinyl group.

(In formula (2), m1 is a number of 0 or more, n1 is each a positive number, and m1 is a hexenyl group (-(CH ₂ ) ₄ CH=CH ₂ in the molecule represented by formula (2). ) in which the content of the vinyl (CH ₂ ═CH—) moiety is in the range of 0.5 to 3.0% by mass, more preferably 1.0 to 2.0% by mass. m1+n1 is a number within a range where 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.)

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

(b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule is the cross-linking agent of component (a) and may have at least three silicon-bonded hydrogen atoms per molecule; Preferably, the bonding position of the hydrogen atom in the molecule is not particularly limited.

Examples of organic groups, other than hydrogen atoms, bonded to silicon atoms contained in component (b) include alkyl groups such as methyl, ethyl, propyl, butyl, and octyl groups. is preferred. The molecular structure of the component (b) organohydrogenpolysiloxane is exemplified by any one of linear, branched, and branched cyclic or a combination of one or more thereof. The number of silicon-bonded hydrogen atoms in one molecule is the average value of all molecules.

The viscosity of component (b) at 25° C. is 1 to 1,000 mPa·s, preferably 5 to 500 mPa·s. This is because when the viscosity of component (b) at 25° C. is less than 1 mPa·s, component (b) tends to volatilize from the crosslinkable composition containing it, and when it exceeds 1,000 mPa·s, the The curing time of the crosslinkable composition containing such a component (b) may become long, or it may cause poor curing. Although such component (b) is not particularly limited, for example, a dimethylsiloxane/methylhydrogensiloxane copolymer having both ends trimethylsiloxy group-blocked, a dimethylsiloxane/methylhydrogensiloxane copolymer having both ends dimethylhydrogensiloxy group-blocked, Examples include a coalescence, dimethylhydrogensiloxy group-blocked dimethylpolysiloxane at both ends, methylhydrogenpolysiloxane blocked at both ends with trimethylsiloxy groups, cyclic methylhydrogenpolysiloxane, and cyclic methylhydrogensiloxane/dimethylsiloxane copolymer.

Here, the value of H/Alk, which is the molar ratio of the alkenyl group content (Alk) in component (a) to the silicon-bonded hydrogen atom content (H) in component (b) (=reaction ratio in the hydrosilylation reaction) is preferably in the range of 0.7 to 1.5. The lower limit of H/Alk is preferably 0.80 or more, 0.85 or more, 0.90 or more, or 0.95 or more, and the upper limit is 1.50 or less, more preferably 1.30 or less. is. If the upper limit of H/Alk exceeds the above value, unreacted silicon-bonded hydrogen atoms tend to remain after the reaction. Conversely, if the upper limit of H/Alk is less than the above value, unreacted alkenyl groups tend to remain after the reaction. Since these are curing reactive groups, if they remain in a large amount in the particles, they cause cross-linking reactions between the particles over time, and the obtained silicone elastomer particles or silicone resin-coated silicone elastomer particles aggregate or coagulate. Poor dispersion and, if reactive hydrogen atoms remain, may cause generation of combustible hydrogen gas over time. Particularly preferably, when the value of H/Alk is in the range of 0.9 to 1.30, the curing reactive groups are completely consumed, the crosslinking reaction is terminated, and the cohesion between particles is effectively prevented over time. can be suppressed to

Component (c) is a hydrosilylation reaction catalyst that accelerates the addition reaction (hydrosilylation reaction) between silicon-bonded alkenyl groups present in the crosslinkable composition and silicon-bonded hydrogen atoms. A preferred hydrosilylation reaction catalyst is a hydrosilylation reaction catalyst containing a platinum-based metal, and specifically includes chloroplatinic acid, alcohol-modified chloroplatinic acid, an olefin complex of chloroplatinic acid, and a complex of chloroplatinic acid and ketones. , a complex of chloroplatinic acid and vinylsiloxane, platinum tetrachloride, platinum fine powder, solid platinum supported on an alumina or silica carrier, platinum black, platinum olefin complex, platinum alkenylsiloxane complex, platinum Examples of platinum-based catalysts include carbonyl complexes, methyl methacrylate resins containing these platinum-based catalysts, thermoplastic organic resin powders such as polycarbonate resins, polystyrene resins, and silicone resins. In particular, a complex of chloroplatinic acid and divinyltetramethyldisiloxane, a complex of chloroplatinic acid and tetramethyltetravinylcyclotetrasiloxane, a platinum divinyltetramethyldisiloxane complex, a platinum tetramethyltetravinylcyclotetrasiloxane complex, etc. Platinum alkenylsiloxane complexes are preferably used. As a catalyst for accelerating the hydrosilylation reaction, non-platinum metal catalysts such as iron, ruthenium, and iron/cobalt may be used.

The amount of component (c) added to the crosslinkable composition may be a catalytic amount, and usually the amount of platinum-based metal contained in component (c) is 1 to 1 with respect to the total mass of the above crosslinkable composition. An amount in the range of 1,000 ppm is preferred, and an amount in the range of 5 to 500 ppm is more preferred. The amount of platinum metal in the silicone elastomer particles may be reduced by the method proposed by the present inventors in JP-A-2014-122316.

The timing at which component (c) is added to the crosslinkable composition can be selected according to the method of forming the silicone elastomer particles, and may be added to the composition in advance. may be supplied from different spray lines, added to one of them and mixed during spraying. Similarly, when passing through an aqueous suspension formed by emulsifying the silicone elastomer particles in water, it may be added in advance to the crosslinkable composition, or an emulsion containing component (c) may be separately added to water. good.

The above crosslinkable composition may contain a curing retarder typified by a hydrosilylation reaction inhibitor. Such curing retarders are exemplified by acetylenic compounds, enyne compounds, organic nitrogen compounds, organic phosphorus compounds, and oxime compounds. Specific compounds include 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 alkyne alcohols such as 1-ethynyl-1-cyclohexanol (ETCH); 3-methyl-3-trimethylsiloxy-1-butyne, 3-methyl-3-trimethylsiloxy-1-pentyne, enyne compounds such as 3,5-dimethyl-3-trimethylsiloxy-1-hexyne, 3-methyl-3-penten-1-yne, and 3,5-dimethyl-3-hexene-1-yne; 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 in the range of 0.001 to 5 parts by mass per 100 parts by mass of component (a), and is appropriately determined according to the type of curing retarder used, the properties and amount of the hydrosilylation reaction catalyst used, etc. Design is possible.

The crosslinkable composition can contain components other than the components described above within a range that does not impair the technical effects of the present invention. For example, 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; hexamethyldisiloxane, octamethyltrisiloxane, silicones such as decamethyltetrasiloxane; esters such as ethyl acetate, butyl acetate and propylene glycol monomethyl ether acetate; organic solvents such as ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; of non-reactive organopolysiloxane (including linear or cyclic organopolysiloxane with a low viscosity of about 0.5 to 10 mPas at 25 ° C.); phenol, quinone, amine, phosphorus, phosphite Antioxidants such as system, sulfur-based, or thioether-based; light stabilizers such as triazole-based or benzophenone-based; flame retardants such as phosphate ester-based, halogen-based, phosphorus-based, or antimony-based; One or more antistatic agents, such as anionic surfactants or nonionic surfactants; dyes; pigments;

[Coating with silicone resin]
In the silicone resin-coated silicone elastomer particles of the present invention, part or all of the surface of the silicone elastomer particles is a silicone resin, preferably D-siloxane represented by R ₂ SiO _2/2 (R is a monovalent organic group). A silicone resin ( _i.e. , _DQ , DT and TQ silicone resins) or a silicone resin composed of T siloxane units represented by RSiO _3/2 (R is a monovalent organic group), particularly preferably coated with a DQ silicone resin. .

Specifically, the silicone resin used for the coating is
i) DQ silicone resins consisting of D siloxane units represented by R ₂ SiO _2/2 (R is a monovalent organic group) and Q siloxane units represented by SiO _4/2 ;
ii) a DT silicone resin consisting of D siloxane units represented by R ₂ SiO _2/2 (R is a monovalent organic group) and T siloxane units represented by RSiO _3/2 (R is a monovalent organic group); and iii) one or more silicone resins selected from TQ silicone resins consisting of T siloxane units represented by RSiO _3/2 (R is a monovalent organic group) and Q siloxane units represented by SiO _4/2 ; or iv) a T-silicone resin composed of T-siloxane units represented by RSiO _3/2 (R is a monovalent organic group).

In the present invention, the silicone resin is preferably a DQ silicone resin represented by R ¹ ₂ SiO _2/2 (R ¹ is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms). and Q siloxane units represented by SiO _4/2 and having a substance amount ratio in the range of 8:2 to 3:7 is particularly preferred. The D units that make up the silicone resin form 2 siloxane bonds to form a linear siloxane bond, while the Q units form 4 siloxane bonds to form a highly branched network or reticulated siloxane bond. Therefore, when the amount of D units is within the above range, a moderately flexible polydiorganosiloxane structure is contained in a large amount in the silicone resin, and the smoothness and flexibility of the silicone resin film on the silicone elastomer particle surface are improved. and followability are improved, and the formation of secondary agglomerated particles is particularly effectively suppressed.

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 the silicone elastomer particles.

More specifically, the above silicone resin is R ₂ Si(OA) ₂ (wherein R is a monovalent organic group, and A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or phenyl group), RSi(OA) ₃ (wherein R is a monovalent organic group, A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group ) and a hydrolyzable silane represented by Si(OA) ₄ (wherein A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group) A mixture of two or more selected hydrolyzable silanes or 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 phenyl group) can be obtained by condensation reaction of hydrolyzable silanes.

In the formula, R is a monovalent organic group, alkyl groups such as methyl group, ethyl group, propyl group and butyl group; cycloalkyl groups such as cyclopentyl group and cyclohexyl group; vinyl group, allyl group, butenyl group and pentenyl group. , alkenyl groups such as hexenyl group, heptenyl group, octenyl group, nonenyl group and decenyl group; aryl groups such as phenyl group, tolyl group and xylyl group; aralkyl groups such as benzyl group, phenethyl group and 3-phenylpropyl group; -halogenated alkyl groups such as chloropropyl group and 3,3,3-trifluoropropyl group; and monovalent hydrocarbon groups such as acryloxy group, methacryloxy group and epoxy group. Industrially, it is preferable to use hydrolyzable silanes in which R is a methyl group or a phenyl group.

In the formula, "OA" is a hydrolyzable hydroxyl group, alkoxy group or phenoxy group, and A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or a phenyl group. From the viewpoint of condensation reactivity to give a silicone resin, OA is particularly preferably an alkoxy group having 1 to 4 carbon atoms, which is a hydroxyl group, a methoxy group, an ethoxy group, a propoxy group and a butoxy group. It is particularly preferred that OA is an alkoxy group having 1 to 4 carbon atoms in the silane.

The silicone resin in the present invention is a silicone resin consisting only of a condensation reaction product of two types of hydrolyzable silanes selected from diorganodialkoxysilanes, organotrialkoxysilanes, and tetraalkoxysilanes, or a condensation reaction product of organotrialkoxysilanes. It is preferably a silicone resin consisting only of DQ silicone resin consisting only of a condensation reaction product of diorganodialkoxysilane and tetraalkoxysilane and having a substance amount ratio within the range of 8:2 to 3:7 is particularly preferred. DQ silicone resin, which is a condensation reaction product of dimethyldimethoxysilane and tetraethoxysilane, is particularly preferred.

The coating of the surface of the silicone elastomer particles with the condensation reaction product of the hydrolyzable silane is not particularly limited. may be obtained by hydrolytically condensing and coating the surface of the silicone elastomer particles with a silicone resin. The timing of adding the alkaline substance or the acidic substance is arbitrary. After forming an emulsified emulsion, the alkaline substance is preferably added to the emulsion after or in conjunction with the hydrosilylation reaction of the crosslinkable silicone.

Preferably, the above hydrolyzable silane is added to the crosslinkable silicone raw material that forms the silicone elastomer particles, and is uniformly mixed using a conventional stirrer such as a propeller blade or flat plate blade. is preferably emulsified in water at

In the emulsified state, the temperature of the aqueous reaction liquid containing the silicone elastomer particles and the alkaline substance is preferably 10 to 60°C, more preferably 10 to 40°C, from the standpoint of uniformly coating the surfaces of the silicone elastomer particles. is in the range of Within the above temperature range, the hydrolysis/condensation reaction of the hydrolyzable silane proceeds moderately on the surface of the silicone elastomer particles, resulting in a uniform silicone resin coating. The stirring of the reaction solution is continued until the desired coating reaction with the silicone resin is completed, and may be carried out at a temperature higher than the above temperature (for example, under heating at 40° C. or higher) for the completion of the reaction.

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

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 carbonate such as sodium; ammonia; tetraalkylammonium hydroxide such as tetramethylammonium hydroxide, tetraethylammonium hydroxide; or monomethylamine, monoethylamine, monopropylamine, monobutylamine, monopentylamine, dimethylamine, diethylamine , trimethylamine, triethanolamine, and ethylenediamine. Among them, ammonia is most suitable because it can be easily removed from the obtained silicone fine particle powder by volatilization. As ammonia, a commercially available ammonia aqueous solution can be used.

After the above hydrolysis/condensation reaction, the silicone resin-coated silicone elastomer particles of the present invention obtained may be used as they are as an aqueous dispersion (aqueous suspension), but water is preferably removed from the reaction solution. By doing so, the silicone resin-coated silicone elastomer particles are isolated. Examples of methods for removing water from the aqueous dispersion include drying using a vacuum dryer, a hot air circulation oven, and a spray dryer. As a pretreatment for this operation, the dispersion may be concentrated by a method such as heat dehydration, filtration separation, centrifugation, or decantation, or if necessary, the dispersion may be washed with water.

In the silicone resin-coated silicone elastomer particles of the present invention, the coating amount of the silicone resin is not particularly limited. parts by weight, particularly preferably from 5.0 to 20.0 parts by weight. If the amount is less than the lower limit, the coating amount of the silicone resin may be insufficient, resulting in insufficient technical effects such as uniform dispersibility in the organic resin. On the other hand, when the coating amount exceeds the above upper limit, the hard physical properties derived from the Q siloxane unit represented by SiO _4/2 and the T siloxane unit represented by RSiO _3/2 in the silicone resin are strongly reflected. As a result, the elasticity and properties as an elastic body derived from the silicone elastomer particles are impaired, and the feel and feel of use when blended in a cosmetic composition deteriorate, and the stress relaxation property when blended in an organic resin decreases. There is

The coating amount of the silicone resin can be easily controlled by controlling the amount of the silicone resin-forming hydrolyzable silane added to the silicone elastomer particle-forming crosslinkable composition.

[Coating State of Silicone Elastomer Particles with Silicone Resin]
The silicone resin-coated silicone elastomer particles according to the present invention are produced by adopting the manufacturing process described above, so that the surfaces of the silicone elastomer particles are evenly and smoothly coated with the silicone resin, and the surface of the silicone resin is coated with extremely few protrusions or irregularities. can be realized. In particular, when spherical silicone elastomer particles are evenly coated with a silicone resin, the smooth particle surface suppresses secondary aggregation between particles and suppresses an increase in secondary particle size, while surface friction is less likely to occur. Therefore, it is possible to achieve stress relaxation and lubricity, as well as a good feel when blended in cosmetics.

[Method for producing organic resin additives and raw materials for organic resins, paints and coating agents]
The silicone resin-coated silicone elastomer particles according to the present invention are excellent in uniform dispersibility in organic resins and, if desired, in stress relaxation properties and the like. A method for producing raw materials for organic resins, paints, and coating agents, including the step for producing silicone resin-coated silicone elastomer particles according to the present invention, is useful.

In particular, members, coatings, or coatings formed by curing an organic resin containing the silicone resin-coated silicone elastomer particles have flexibility (including the softness of the coating layer), durability, and adherence/follow-up to substrates. It is extremely useful as a highly functional organic resin, paint or coating agent for use in electronic materials because of its improved properties, especially its excellent flexibility and thermal shock resistance.

[Organic resin]
Preferred examples of the organic resin containing the silicone resin-coated silicone elastomer particles of the present invention include curable organic resin compositions and thermoplastic resins. Among these, curable resins are suitable for electronic materials such as semiconductor substrates. More specifically, curable organic resin compositions include phenol 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, copolymer resins of these resins are exemplified, and two or more of these curable resins can be combined. In particular, the curable resin is preferably at least one selected from the group consisting of epoxy resins, phenol resins, imide resins, and silicone resins. Any compound containing a glycidyl group or an alicyclic epoxy group can be used as the epoxy resin. type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, naphtholaralkyl type epoxy resin, polyvinylphenol type epoxy resin, diphenylmethane type epoxy resin, diphenylsulfone type epoxy resin, triphenolalkane type epoxy resin Resins, cresol-naphthol cocondensation type epoxy resins, bisphenylethylene type epoxy resins, fluorene type epoxy resins, stilbene type epoxy resins, spirocumaron type epoxy resins, norbornene type epoxy resins, terpene type epoxy resins, phenolcyclohexane type epoxy resins, halogens Examples include modified epoxy resins, imide group-containing epoxy resins, maleimide group-containing epoxy resins, allyl group-modified epoxy resins, and silicone-modified epoxy resins. As the phenol resin, polyvinylphenol type, phenol novolak type, naphthol type, terpene type, phenoldicyclopentadiene type, phenol aralkyl type, naphthol aralkyl type, triphenol alkane type, dicyclopentadiene type, cresol/naphthol Condensed type and xylene/naphthol co-condensed type are exemplified. Examples of silicone resins include epoxy-modified silicone resins obtained by reacting epoxy resins with silanol groups or silicon-bonded alkoxy groups in silicone resins. Examples of the curing mechanism of such a curable resin include a thermosetting type, a high-energy ray-curing type such as ultraviolet rays or radiation, a moisture-curing type, a condensation reaction-curing type, and an addition reaction-curing type. Moreover, the properties of such a curable resin at 25° C. are not limited, and may be liquid or solid that softens when heated.

The organic resin containing the silicone resin-coated silicone elastomer particles of the present invention 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, a plasticizer, and the like. can be blended. 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; primary or secondary amino compounds; Two or more of these may be combined. Further, the curing accelerator includes tertiary amine compounds, organic metal compounds such as aluminum and zirconium; organic phosphorus compounds such as phosphine; other heterocyclic amine compounds, boron complex compounds, organic ammonium salts, organic sulfonium salts, Examples include organic peroxides and hydrosilylation catalysts. Examples of fillers include 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, and phenol fiber. , fibrous fillers such as natural animal and plant fibers; fused silica, precipitated silica, fumed silica, calcined silica, zinc oxide, calcined clay, carbon black, glass beads, alumina, talc, calcium carbonate, clay, aluminum hydroxide, Granular fillers such as barium sulfate, titanium dioxide, aluminum nitride, silicon carbide, magnesium oxide, beryllium oxide, kaolin, mica, and zirconia are exemplified, and two or more of these may be combined. In the case of an epoxy resin, it is particularly preferred to contain an amine curing agent.

The silicone resin-coated silicone elastomer particles according to the present invention may be blended with thermoplastic resins other than those described above as additives, and may be used as modifiers of physical properties such as surface lubricants and stress relaxation agents, or as light scattering agents. It can be used as a modifier of optical properties. The type of thermoplastic resin is not particularly limited, and may be polycarbonate resin, polyester resin, polyether resin, polylactic acid resin, polyethylene, polypropylene, polyolefin resin such as ethylene-propylene copolymer, polystyrene. At least one type of polymer selected from the group consisting of resins, styrenic copolymers, fluorine-based polymers such as tetrafluoroethylene, polyvinyl ethers, and cellulose-based polymers, or a composite resin consisting of a combination thereof There may be. The silicone resin-coated silicone elastomer particles of the present invention can be uniformly dispersed in these thermoplastic resins (including masterbatch) by using a mixing device such as a twin-screw/single-screw extruder or a kneader mixer, and a film can be obtained. It may be used after being molded into a desired shape such as a shape.

The amount of the silicone resin-coated silicone elastomer particles according to the present invention to be added can be appropriately selected according to the physical properties required for the organic resin, but generally it is 0.1 to 30 parts by mass per 100 parts by mass of the organic resin. range and may range from 0.5 to 10 parts by weight. If the amount of the particles added is less than the above lower limit, performance such as stress relaxation properties for resins and the like may be insufficient, and the flexibility and thermal shock resistance of the obtained organic resin cured product may be reduced. This is because the subsequent thermal shock resistance tends to decrease. On the other hand, if the above upper limit is exceeded, the viscosity of the organic resin or paint/coating agent after blending may increase and handling workability may decrease, and the mechanical properties of the resulting cured organic resin tend to decrease. It is from.

Furthermore, when the silicone resin-coated silicone elastomer particles of the present invention are blended with an organic resin, they exhibit excellent stress relaxation effects. A copper foil with a filler particle-containing resin layer for a printed wiring board having a resin layer containing the silicone resin-coated silicone elastomer particles of the present invention on one side of a copper foil is formed and used for copper clad laminate (CCL) applications. can do

[Paints, coating agents]
Examples of the paint/coating agent containing the silicone resin-coated silicone elastomer particles according to the present invention include room temperature curing type, room temperature drying type, and heat curing type, as well as water-based, oil-based, and powdery depending on the properties thereof. , depending on the vehicle resin, polyurethane resin paint, butyral resin paint, long oil phthalate resin paint, alkyd resin paint, amino alkyd resin paint consisting of amino resin and alkyd resin, epoxy resin paint, acrylic resin paint, phenol resin paint, silicone Examples include modified epoxy resin paint, silicone modified polyester resin paint, and silicone resin paint.

The amount of the silicone resin-coated silicone elastomer particles according to the present invention to be added can be appropriately selected according to the physical properties required for the paint/coating agent. is preferably in the range of 0.1 to 150 parts by mass, more preferably in the range of 0.1 to 100 parts by mass, with respect to 100 parts by mass of the solid content of the paint. .1 to 50 parts by weight, preferably 0.1 to 20 parts by weight. If the amount of the particles added is less than the above lower limit, performance such as matte properties, adhesion, and stress relaxation properties for the coating film may be insufficient.・The coating agent may thicken and the handling workability may decrease.

Paints and coating agents containing the silicone resin-coated silicone elastomer particles of the present invention include 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 dimethylformamide; olefins such as hexane, heptane, octane; organic solvents such as aromatic hydrocarbons such as toluene and xylene; known inorganic fillers such as reinforcing silica, organic fillers, curing accelerators, silanes It may contain a coupling agent, a pigment such as carbon black, a dye, an antioxidant, a thickener composed of a polymer compound, a flame retardant, and a weather resistance imparting agent.

[Cosmetic composition]
The silicone resin-coated silicone elastomer particles according to the present invention are also useful as a raw material for cosmetics. It has excellent oil absorption properties and uniform dispersibility in other cosmetic ingredients (especially oil-based ingredients). and has the advantage of being excellent in usability. Furthermore, the silicone resin-coated silicone elastomer particles of the present invention are less likely to scatter and less likely to adhere to containers, and thus are excellent in handling workability and compounding stability.

The cosmetic composition containing the silicone resin-coated silicone elastomer particles according to the present invention is not particularly limited in its type, but it can be used as cleansing cosmetics such as soaps, body shampoos, and facial cleansing creams; Basic cosmetics such as , packs; Base makeup cosmetics such as face powder and foundation; Eyebrow cosmetics such as lipstick, blush, eye shadow, eyeliner, and mascara; Makeup cosmetics such as manicure; Shampoo, hair rinse, hair styling , hair tonics, hair tonics, hair dyes and other hair cosmetics; perfumes, fragrant cosmetics such as eau de cologne; toothpaste; Special cosmetics such as sunscreen agents are exemplified. Examples of dosage forms of these cosmetic compositions include aqueous liquids, oily liquids, milky lotions, creams, foams, semisolids, solids, and powders. Moreover, these cosmetic compositions can also be used by spraying.

In these cosmetic compositions, the content of the above silicone resin-coated silicone elastomer particles is preferably in the range of 0.5 to 99.0% by mass, particularly 1.0% by mass of the cosmetic composition. It is preferably in the range of to 95% by mass. This is because if the content of the silicone resin-coated silicone elastomer particles exceeds the upper limit of the above range, the effect as a cosmetic is lost. This is because it becomes difficult to improve the feeling of use of the composition.

The silicone resin-coated silicone elastomer particles of the present invention have ), Patent Document 5 (International Patent Publication WO2017/191798) and Japanese Patent Application Laid-Open No. 2014-122316, a cosmetic composition containing silicone particles (silicone rubber powder, etc.) or silicone composite particles (in particular, each formulation example ) can be used by replacing some or all of these silicone-based particles, and it may be possible to further improve the usability and production efficiency of the cosmetic compositions proposed in these patent documents.

Furthermore, the silicone resin-coated silicone elastomer particles of the present invention can be applied by replacing some or all of these silicone-based particles in the applications and formulations of the cosmetic compositions disclosed in the above patent documents. , and their use is within the scope of the present invention. The silicone resin-coated silicone elastomer particles of the present invention can also be used in the cosmetic compositions disclosed in the above-mentioned patent documents, etc. including), water, coloring agents, alcohols, water-soluble polymers, film-forming agents, oils, oil-soluble gelling agents, organic modified clay minerals, surfactants, resins, salts, moisturizers, preservatives, antibacterial agents, Antioxidants, pH adjusters, chelating agents, cooling agents, anti-inflammatory agents, skin-beautifying ingredients (whitening agents, cell activators, rough skin improvers, blood circulation promoters, skin astringents, antiseborrheic agents, etc.), vitamins , amino acids, nucleic acids, hormones, clathrate compounds, etc., physiologically active substances, active pharmaceutical ingredients, perfumes, etc., may be used in combination, and is preferred.

In particular, the silicone resin-coated silicone elastomer particles of the present invention are superior to conventionally known silicone particles and silsesquioxane-coated silicone composite particles in terms of oil absorption, and therefore contain oily cosmetic raw materials such as oils. A particularly favorable feeling of use can be achieved in cosmetic compositions and formulations.

The cosmetic of the present invention can be easily produced by simply homogeneously mixing the above-described cosmetic raw material of the present invention with other cosmetic raw materials. As a mixing means, various mixing devices and kneading devices that are commonly used in the production of cosmetics can be used. Examples of such devices include homomixers, paddle mixers, Henschel mixers, homodispers, colloid mixers, propeller stirrers, homogenizers, in-line continuous emulsifiers, ultrasonic emulsifiers, and vacuum kneaders.

The silicone resin-coated silicone elastomer particles of the present invention and the method for producing the same will be described in detail with reference to examples and comparative examples. However, the present invention is not limited only to those examples. Viscosities in the examples are values at 25°C. Also, the properties of each silicone particle were measured as follows. Unless otherwise specified in the examples and the like, silicone particles are a general term for particles made of cured silicone (cured silicone particles), and do not include emulsions.

[JIS A hardness of silicone particles]
A curable silicone composition, which is a raw material for silicone elastomer particles, was heated in a heating oven at 150° C. for 1 hour to cure into a sheet. The hardness was measured with a JIS A hardness tester defined in JIS K6253.

[Average primary particle size of emulsion particles]
The emulsion before adding the platinum catalyst was measured by a laser diffraction particle size distribution analyzer (Beckman Coulter LS-230), and the median diameter (particle size corresponding to 50% of the cumulative distribution, 50% particle size ) was taken as the average particle size.

[Average secondary particle size of silicone particles (powder)]
Using ethanol as a dispersion medium, measure the particle size of the cured silicone particles with a laser diffraction particle size distribution analyzer (Horiba LA-750). The values of the particle size, D90, μm) and the arithmetic dispersity (SD, μm2, which indicates the degree of dispersion of the particle size distribution) were obtained. A measurement sample was obtained by dispersing cured silicone particles (1 g) and ethanol (100 mL) in a 300 mL cup using a stirring blade and an ultrasonic vibrator.

[Uniform dispersibility in epoxy resin solution]
7 g of silicone particles were added to 35 g of an epoxy resin solution (solid content: 59.2%), stirred with a homodisper, and the viscosity of the mixture was measured with a Brookfield E-type viscometer.
An epoxy resin solution was prepared according to the following recipe.
Flame-retardant epoxy resin (manufactured by DIC, trade name “EPICLON 1121N-80M”) 434.8 g
Multifunctional epoxy resin (manufactured by Mitsubishi Chemical Corporation, trade name "jER154") 122.3 g
2-butanone 89.4g
2-methoxyethanol 158.6 g

Average formulas of component (A) and component (B) used in Examples and Comparative Examples are listed below.
In the following formulas, Vi is a vinyl group represented by CH ₂ ═CH—, Me is a methyl group represented by CH ₃ —, and Hex is a hexenyl group represented by CH ₂ ═CH—C ₄ H ₈ —. each shown.
[Chemical 1-1]
_Me2HexSiO- ( _Me2SiO )57-( _MeHexSiO ) ₃ - _SiHexMe2 ,
The alkenyl group content is 2.7 wt%. Viscosity is 100mPa·s.
[Chemical 1-2]
( _Me2ViSiO ) _4Si ,
The alkenyl group content is 23.25 wt%. Viscosity is 3 mPa·s.
[Chemical 1-3]
Me ₂ ViSiO—(Me ₂ SiO) ₁₄₁ —(MeViSiO) ₂ —SiViMe ₂ ,
The alkenyl group content is 1.08 wt%. Viscosity is 370mPa·s.
[Chemical 2-1]
( _Me3SiO1 /2) ₂ ( _Me2SiO2 / ₂ ) ₇ ( _{HMeSiO2 /2} ) ₁₁ ( _MeSiO3/2 ) ₁ ,
Silicon-bonded hydrogen atom content is 0.825 wt%. Viscosity is 15 mPa·s.
[Chemical 2-2]
Me ₃ SiO _1/2 -(Me ₂ SiO _2/2 ) ₃₉ -(HMeSiO _2/2 ) ₁₂ -SiMe ₃ .
Silicon-bonded hydrogen atom content is 0.309 wt%. Viscosity is 47 mPa·s.

[Example 1]
Polyorganosiloxane represented by the average formula of [Formula 1-1] and polyorganosiloxane represented by the average formula of [Formula 2-1] were uniformly mixed at a mass ratio of 89:11 at room temperature. 14 parts by mass of tetraethoxysilane and 10 parts by mass of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution of 3.0 parts by mass of polyoxyethylene sorbitan laurate and 20 parts by mass of pure water at 25° C., and further emulsified uniformly by a colloid mill. The average primary particle size was 1.4 μm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (the amount of platinum metal in the present composition is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene sorbitan laurate and pure water, and then stirred. After the emulsion was allowed to stand at 50° C. for 1 hour to carry out a hydrosilylation reaction, 20 parts by mass of 28% aqueous ammonia was added. The pH of the liquid at this time was 11. Further, the mixture was allowed to stand still for 1 hour to allow condensation reaction of the silane to prepare a uniform aqueous suspension of the silicone rubber particles coated with the silicone resin. Next, this water-based suspension was dried with a small spray dryer (manufactured by Ashizawa Niro Co., Ltd.) to obtain silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 68 and an average secondary particle size of 2.2 μm.

[Example 2]
The polyorganosiloxane represented by the average formula of [Formula 1-2] and the polyorganosiloxane represented by the average formula of [Formula 2-2] were uniformly mixed at a mass ratio of 25:75 at room temperature. 9 parts by mass of tetraethoxysilane and 4 parts by mass of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution of 3.0 parts by mass of polyoxyethylene sorbitan laurate and 20 parts by mass of pure water at 25° C., and further emulsified uniformly by a colloid mill. The average primary particle size was 1.4 μm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (the amount of platinum metal in the present composition is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene sorbitan laurate and pure water, and then stirred. After the emulsion was allowed to stand at 50° C. for 3 hours to carry out a hydrosilylation reaction, 20 parts by mass of 28% aqueous ammonia was added. The pH of the liquid at this time was 11. Further, the mixture was allowed to stand still for 1 hour to allow condensation reaction of the silane to prepare a uniform aqueous suspension of the silicone rubber particles coated with the silicone resin. Next, this water-based suspension was dried with a small spray dryer (manufactured by Ashizawa Niro Co., Ltd.) to obtain silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 83 and an average secondary particle size of 3.2 μm.

[Example 3]
Polyorganosiloxane represented by the average formula of [Formula 1-3] and polyorganosiloxane represented by the average formula of [Formula 2-1] were uniformly mixed at a mass ratio of 96:4 at room temperature. 14 parts by mass of tetraethoxysilane and 10 parts by mass of dimethyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution of 3.0 parts by mass of polyoxyethylene sorbitan laurate and 20 parts by mass of pure water at 25° C., and further emulsified uniformly by a colloid mill. The average primary particle size was 1.1 μm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (the amount of platinum metal in the present composition is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene sorbitan laurate and pure water, and then stirred. After the emulsion was allowed to stand at 50° C. for 3 hours to carry out a hydrosilylation reaction, 20 parts by mass of 28% aqueous ammonia was added. The pH of the liquid at this time was 11. Further, the mixture was allowed to stand still for 1 hour to allow condensation reaction of the silane to prepare a uniform aqueous suspension of the silicone rubber particles coated with the silicone resin. Next, this water-based suspension was dried with a small spray dryer (manufactured by Ashizawa Niro Co., Ltd.) to obtain silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 50 and an average secondary particle size of 4.0 μm.

[Example 4]
Polyorganosiloxane represented by the average formula of [Formula 1-1] and polyorganosiloxane represented by the average formula of [Formula 2-1] were uniformly mixed at a mass ratio of 89:11 at room temperature. 14 parts by mass of tetraethoxysilane and 7 parts by mass of diphenyldimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution of 3 parts by mass of polyoxyethylene alkyl (C12-14) ether and 20 parts by mass of pure water at 25°C, and further emulsified uniformly by a colloid mill. The average primary particle size was 0.9 μm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in this composition, the amount of platinum metal is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene alkyl (C12-14) ether and pure water. After the emulsion was stirred at 50° C. for 1 hour to carry out a hydrosilylation reaction, 20 parts by mass of 28% aqueous ammonia was added. The pH of the liquid at this time was 11. Further, the mixture was allowed to stand still for 1 hour to allow condensation reaction of the silane to prepare a uniform aqueous suspension of the silicone rubber particles coated with the silicone resin. Next, this water-based suspension was dried with a small spray dryer (manufactured by Ashizawa Niro Co., Ltd.) to obtain silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 68 and an average secondary particle size of 1.6 μm.

[Comparative Example 1]
Polyorganosiloxane represented by the average formula of [Formula 1-1] and polyorganosiloxane represented by the average formula of [Formula 2-1] were uniformly mixed at a mass ratio of 89:11 at room temperature. Next, this composition was dispersed in an aqueous solution of 3 parts by mass of polyoxyethylene alkyl (C12-14) ether and 20 parts by mass of pure water at 25°C, and further emulsified uniformly by a colloid mill. The average primary particle size was 1.5 μm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in this composition, the amount of platinum metal is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene alkyl (C12-14) ether and pure water. After stirring, the emulsion was allowed to stand at 50°C for 1 hour to prepare a uniform aqueous suspension of silicone rubber particles. Next, this water-based suspension was dried with a small spray dryer (manufactured by Ashizawa Niro Co., Ltd.) to obtain silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 68 and an average secondary particle size of 3.1 μm.

[Comparative Example 2]
The polyorganosiloxane represented by the average formula of [Formula 1-2] and the polyorganosiloxane represented by the average formula of [Formula 2-2] were uniformly mixed at a mass ratio of 25:75 at room temperature. Next, this composition was dispersed in an aqueous solution of 3.0 parts by mass of polyoxyethylene alkyl (C12-14) ether and 20 parts by mass of pure water at 25°C, and further emulsified uniformly by a colloid mill. The average primary particle size was 1.3 μm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in this composition, the amount of platinum metal is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene alkyl (C12-14) ether and pure water. After stirring, the emulsion was allowed to stand at 50°C for 3 hours to prepare a uniform aqueous suspension of silicone rubber particles. Next, this water-based suspension was dried with a small spray dryer (manufactured by Ashizawa Niro Co., Ltd.) to obtain silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 83 and an average secondary particle size of 4.6 μm.

[Comparative Example 3]
Polyorganosiloxane represented by the average formula of [Formula 1-3] and polyorganosiloxane represented by the average formula of [Formula 2-1] were uniformly mixed at a mass ratio of 96:4 at room temperature. Next, this composition was dispersed in an aqueous solution of 3.0 parts by mass of polyoxyethylene alkyl (C12-14) ether and 20 parts by mass of pure water at 25°C, and further emulsified uniformly by a colloid mill. The average primary particle size was 1.5 μm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in this composition, the amount of platinum metal is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene alkyl (C12-14) ether and pure water. After stirring, the emulsion was allowed to stand at 50°C for 3 hours to prepare a uniform aqueous suspension of silicone rubber particles. Next, this water-based suspension was dried with a small spray dryer (manufactured by Ashizawa Niro Co., Ltd.) to obtain silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 50 and an average secondary particle size of 56.7 μm.

[Comparative Example 4]
Polyorganosiloxane represented by the average formula of [Formula 1-1] and polyorganosiloxane represented by the average formula of [Formula 2-1] were uniformly mixed at a mass ratio of 89:11 at room temperature. Next, this composition was dispersed in an aqueous solution of 3.0 parts by mass of polyoxyethylene alkyl (C12-14) ether and 20 parts by mass of pure water at 25°C, and further emulsified uniformly by a colloid mill. The average primary particle size was 1.0 µm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (in this composition, the amount of platinum metal is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene alkyl (C12-14) ether and pure water. After stirring at 50° C. for 1 hour, the emulsion was allowed to stand at 50° C. to prepare a uniform aqueous suspension of silicone rubber particles. The resulting silicone elastomer particles had a JIS-A hardness of 68 and an average primary particle size of 1.0 μm.

500 g of the silicone elastomer particle aqueous dispersion obtained in Preparation Example 1 was transferred to a 2-liter glass flask equipped with a stirring device equipped with a stirring blade, and 500 g of water and 20 g of 28% aqueous ammonia were added. The pH of the liquid at this time was 11. After adjusting the temperature to 5 to 10° C., 35 g of tetraethoxysilane (15 parts by weight per 100 parts by weight of silicone elastomer particles before coating with a silicone resin composed of siloxane units represented by SiO _4/2 after hydrolysis/condensation reaction) amount) was added dropwise over 30 minutes, and the mixture was further stirred for 1 hour. During this time, the liquid temperature was kept at 5-10°C. Then, the mixture was heated to 55 to 60° C. and stirred for 1 hour while maintaining the temperature to complete the hydrolysis/condensation reaction of tetraethoxysilane.

The obtained silicone elastomer particles/tetraethoxysilane hydrolysis/condensation reaction liquid was filtered. The dehydrated material was transferred to a stainless steel tray, dried in a hot air circulation dryer at a temperature of 105°C, and the dried material was pulverized by a jet mill to obtain fine particles with fluidity. Observation of the fine particles with an electron microscope revealed that the particles were spherical particles coated with a silicone resin on the surface, and silicone elastomer particles coated with a silicone resin having a surface composed of a siloxane unit represented by SiO _4/2 were coated with a silicone resin. It was confirmed that The average primary particle size of the obtained silicone resin-coated silicone elastomer particles was 5.3 μm.

[Example 5]
Polyorganosiloxane represented by the average formula of [Formula 1-1] and polyorganosiloxane represented by the average formula of [Formula 2-1] were uniformly mixed at a mass ratio of 89:11 at room temperature. 3 parts by weight of dimethyldimethoxysilane and 16 parts by weight of methyltrimethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution of 3 parts by mass of polyoxyethylene sorbitan laurate and 20 parts by mass of pure water at 25° C., and further emulsified uniformly by a colloid mill. The average primary particle size was 1.3 μm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (the amount of platinum metal in the present composition is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene sorbitan laurate and pure water, and then stirred. After the emulsion was allowed to stand at 50° C. for 1 hour to carry out a hydrosilylation reaction, 20 parts by mass of 28% aqueous ammonia was added. The pH of the liquid at this time was 11. Further, the mixture was allowed to stand still for 1 hour to allow condensation reaction of the silane to prepare a uniform aqueous suspension of the silicone rubber particles coated with the silicone resin. Next, this water-based suspension was dried with a small spray dryer (manufactured by Ashizawa Niro Co., Ltd.) to obtain silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 68 and an average secondary particle size of 2.5 μm.

[Example 6]
Polyorganosiloxane represented by the average formula of [Formula 1-1] and polyorganosiloxane represented by the average formula of [Formula 2-1] were uniformly mixed at a mass ratio of 89:11 at room temperature. 16 parts by mass of methyltrimethoxysilane and 7 parts by mass of tetraethoxysilane were added and further mixed. Next, this composition was dispersed in an aqueous solution of 3 parts by mass of polyoxyethylene sorbitan laurate and 20 parts by mass of pure water at 25° C., and further emulsified uniformly by a colloid mill. The average primary particle size was 1.0 μm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (the amount of platinum metal in the present composition is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene sorbitan laurate and pure water, and then stirred. After the emulsion was allowed to stand at 50° C. for 1 hour to carry out a hydrosilylation reaction, 20 parts by mass of 28% aqueous ammonia was added. The pH of the liquid at this time was 11. Further, the mixture was allowed to stand still for 1 hour to allow condensation reaction of the silane to prepare a uniform aqueous suspension of the silicone rubber particles coated with the silicone resin. Next, this water-based suspension was dried with a small spray dryer (manufactured by Ashizawa Niro Co., Ltd.) to obtain silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 68 and an average secondary particle size of 1.6 μm.

[Example 7]
Polyorganosiloxane represented by the average formula of [Formula 1-1] and polyorganosiloxane represented by the average formula of [Formula 2-1] were uniformly mixed at a mass ratio of 89:11 at room temperature. 20 parts by mass of methyltrimethoxysilane was added and further mixed. Next, this composition was dispersed in an aqueous solution of 3 parts by mass of polyoxyethylene sorbitan laurate and 20 parts by mass of pure water at 25° C., and further emulsified uniformly by a colloid mill. The average primary particle size was 1.0 μm. After that, 350 parts by mass of pure water was added to dilute the emulsion to prepare an emulsion. Next, an isopropyl alcohol solution of chloroplatinic acid (the amount of platinum metal in the present composition is 10 ppm by mass) is added to the emulsion as an aqueous dispersion with polyoxyethylene sorbitan laurate and pure water, and then stirred. After the emulsion was allowed to stand at 50° C. for 1 hour to carry out a hydrosilylation reaction, 20 parts by mass of 28% aqueous ammonia was added. The pH of the liquid at this time was 11. Further, the mixture was allowed to stand still for 1 hour to allow condensation reaction of the silane to prepare a uniform aqueous suspension of the silicone rubber particles coated with the silicone resin. Next, this water-based suspension was dried with a small spray dryer (manufactured by Ashizawa Niro Co., Ltd.) to obtain silicone resin-coated silicone elastomer particles. The resulting silicone elastomer particles had a JIS-A hardness of 68 and an average secondary particle size of 2.6 μm.

＊ジフェニル基を含むＤシロキサン単位 Table 1 shows the characteristics of Examples 1 to 7 and Comparative Examples 1 to 4. In addition, the chemical species of the silalkylene bond between silicon atoms in the silicone elastomer particles, the JIS hardness when there is no coating, and the type of silicone resin used for coating the surface of the silicone elastomer particles (siloxane represented by D, Q, T units) are shown in the table.

*D siloxane unit containing diphenyl group

[Summary]
By the production method according to the present invention, it was possible to synthesize silicone resin-coated silicone elastomer particles having a relatively small average secondary particle size and a low mixed viscosity with an epoxy resin (Examples 1 to 7). On the other hand, unlike the present invention, in Comparative Example 4, in which the silicone elastomer particles were synthesized in advance and then coated with the silicone resin, the average secondary particle size increased and agglomeration easily occurred, and the particles were mixed with the epoxy resin. Viscosity also increased significantly. In particular, when Example 1 and Comparative Example 4 are compared in electron micrographs (FIGS. 1 and 2), the coated state of Example 1 is uniform and smooth, while Comparative Example 4 has many protrusions and irregularities. It can be seen that the state of the particle surface is clearly different.

[Prescription example]
The silicone resin-coated silicone elastomer particles obtained by the production method of the present invention are disclosed in Patent Document 2 (JP-A-2011-105663), Patent Document 3 (JP-A-2011-168634), and Patent Document 4 (Patent Document 4). Japanese Patent Laid-Open No. 2011-102354), Patent Document 5 (International Patent Publication WO2017/191798) and Japanese Patent Laid-Open No. 2014-122316. can be used by replacing a part or all of these silicone-based particles.

The method for producing silicone resin-coated silicone elastomer particles of the present invention can be easily carried out on an industrial scale, and not only is the production efficiency remarkably excellent, but aggregation of the obtained silicone resin-coated silicone elastomer particles over time is suppressed. Since it is excellent in storage stability, handling workability, and blending stability, and has excellent uniform dispersibility in organic resins, oil-based raw materials, etc., it is easy to blend as an additive, and the above curable organic resins (semiconductor materials, It is useful as an organic resin additive for paints, coating agents, etc. Furthermore, when the silicone resin-coated silicone elastomer particles of the present invention are blended into cosmetics as raw materials for cosmetics, they can improve the feel of the cosmetics, and can be used in skin cosmetics, makeup cosmetics, and the like. In addition, taking advantage of its physical properties, the silicone resin-coated silicone elastomer particles of the present invention can be used as an additive for thermosetting resin compositions, thermoplastic resin compositions, etc., or for plastic films as an application to electronic materials. It can also be used as a surface lubricant.

Claims (7)

A method for producing silicone resin-coated silicone elastomer particles, comprising the following steps (I), (II) and (III);
Step (I):
(a) an organopolysiloxane having at least two alkenyl groups having 2 to 20 carbon atoms in the molecule;
(b) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule, and
(d) (d1-1) R ¹ ₂ Si(OA) ₂ (wherein R ¹ is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or a phenyl group), and
A hydrolyzable silane represented by Si(OA) ₄ (wherein A is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group) at a substance amount ratio of 8:2 to 3:7. mixtures of hydrolyzable silanes containing within
Step (II) of emulsifying a mixture containing in water:
Step (III) of curing the emulsion obtained in step (I) in the presence of (c) a hydrosilylation reaction catalyst to obtain spherical silicone elastomer particles:
Simultaneously with step (II) or after step (II), the step of coating the surface of the silicone elastomer particles with (d) a silicone resin that is a condensation reaction product of the hydrolyzable silane. The molar ratio of alkenyl group content (Alk) in component (a) to silicon-bonded hydrogen atom content (H) in component (b) is H/Alk=0.7 to 1.5
The method for producing silicone resin-coated silicone elastomer particles according to claim 1 , wherein the range of 3. The silicone resin-coated silicone according to claim 1, further comprising a step of removing moisture from the aqueous dispersion containing the silicone resin-coated silicone elastomer particles (including aggregates) obtained in step (III). A method for producing elastomer particles. Further, the silicone resin-coated silicone elastomer particles (including agglomerates) obtained in step (III) are crushed using mechanical means to obtain an average primary particle size of 0.5 to 0.5 as measured by a laser diffraction scattering method. 4. The method for producing silicone resin-coated silicone elastomer particles according to any one of claims 1 to 3 , comprising a step of obtaining silicone resin-coated silicone elastomer particles of 20 μm. A method for producing an organic resin additive, comprising the method for producing the silicone resin-coated silicone elastomer particles according to any one of claims 1 to 4 . A method for producing a raw material for a paint or a coating agent, comprising the method for producing the silicone resin-coated silicone elastomer particles according to any one of claims 1 to 4 . A method for producing a cosmetic raw material, comprising the method for producing the silicone resin-coated silicone elastomer particles according to any one of claims 1 to 4 .

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