Resin fine particles, method for producing same, and use thereof

Abstract

Provided are resin fine particles that include reduced amounts of a metal component and an eluted ion component and that have excellent dielectric characteristics. Also provided is a method for producing such resin particles.　Resin fine particles according to an embodiment of the present invention have a total content of components A of 100 ppm or less as measured by inductively coupled plasma light emission analysis, a total amount of eluted ion components B of 100 ppm or less as measured by an ion chromatograph, and a dielectric loss tangent at a frequency of 10 GHz of 0.0050 or less. Component A is Al, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, P, S, Si, Sr, and Zn. Ion component B is fluoride ions, chloride ions, nitrite ions, bromide ions, nitrate ions, phosphate ions, and sulfate ions.

Description

Resin microparticles, their manufacturing method, and their uses

[0001] The present invention relates to resin microparticles, a method for producing the same, and uses thereof.

[0002] Resin microparticles are used in a wide range of applications, including as antiblocking agents for light diffusion plates and various film membranes, various film modifiers, spacers between small parts of various electronic devices, pore-forming agents for various battery components, and core particles for conductive microparticles that provide electrical connections.

[0003] In recent years, the semiconductor component market has seen a variety of studies aimed at miniaturizing and improving the performance of electronic circuits. For example, it has been reported that adding fillers to various semiconductor components, such as sealants, interlayer insulating films, and copper-clad laminates, can result in semiconductor components with improved physical properties, such as elasticity, while maintaining good dielectric properties (Patent Document 1). However, when using resin microparticles for such applications, the resin microparticles must be made small enough to miniaturize the semiconductor components, have a low dielectric loss tangent, and have their metal or ionic components reduced in advance to prevent ion migration.

[0004] Emulsion polymerization and seed polymerization are methods for producing resin microparticles with an average particle size of 1 μm or less. However, these polymerizations require a large amount of surfactant to emulsify oil droplets, which results in a problem of a large amount of residual ionic components in the resulting resin microparticles. A washing process for washing particles has been reported as a technique for reducing the residual ionic components (Patent Document 2). However, more precise washing requires a large amount of washing water, which is problematic in terms of production and cost.

[0005] Low ionic resin particles produced without using surfactants or emulsifiers have been reported (Patent Document 3). However, the low ionic resin particles described in Patent Document 3 have a problem in that the particles themselves have a high dielectric loss tangent because they have polar groups such as amino groups on the particle surface.

[0006] Hollow particles that can lower the dielectric constant of semiconductor materials have been reported (Patent Document 4). However, because they are hollow particles, there are problems with strength.

[0007] JP 2023-165254 A International Publication No. 2015 / 045448 JP 2005-082695 A JP 2022-117594 A

[0008] The present invention has been made to solve the above-mentioned problems of the prior art, and its main object is to provide resin microparticles that have reduced metal components and eluted ion components and have excellent dielectric properties, a method for producing such resin microparticles, and uses of such resin microparticles.

[0009] [1] Resin microparticles according to an embodiment of the present invention have a total content of component A of 100 ppm or less as measured by inductively coupled plasma atomic emission spectrometry, a total amount of eluted ion component B of 100 ppm or less as measured by ion chromatography, and a dielectric loss tangent of 0.0050 or less at a frequency of 10 GHz. Component A: Al, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, P, S, Si, Sr, and Zn. Ion component B: fluoride ions, chloride ions, nitrite ions, bromide ions, nitrate ions, phosphate ions, and sulfate ions. [2] The resin microparticles described in [1] above may have a dielectric loss tangent of 0.0030 or less. [3] The resin microparticles described in [1] or [2] above contain a polymer (P) obtained by reaction of a composition containing a radically polymerizable monomer component (M), and the monomer component (M) may contain a crosslinkable monomer (a) and an aromatic monofunctional monomer (b). [4] In the resin microparticles described in [3] above, the crosslinkable monomer (a) may include an aromatic crosslinkable monomer. [5] In the resin microparticles described in [3] or [4] above, the composition may include a reactive surfactant (A). [6] The resin microparticles described in any one of [1] to [5] above may have a volume average particle diameter of 0.05 μm or more and 2 μm or less. [7] In the resin microparticles described in any one of [1] to [6] above, the proportion of particles having a particle diameter of 10 μm or more may be 0.01 vol% or less. [8] The resin microparticles described in any one of [1] to [7] above may be in the form of a dry powder. [9] In the resin microparticles described in any one of [1] to [8] above, the coefficient of variation of the volume average particle diameter may be 25% or less.

[10] The resin microparticles described in any one of [1] to [9] above may be used as an additive for electronic materials.

[11] The resin microparticles according to any one of [1] to [9] above may be used as an additive for optical materials.

[12] The resin microparticles according to any one of [1] to [9] above may be used as an additive for paints.

[13] The resin microparticles according to any one of [1] to [9] above may be used as an additive for inks.

[14] A method for producing resin microparticles according to an embodiment of the present invention is the method for producing resin microparticles described in any one of [1] to

[13] above, comprising performing two-stage polymerization consisting of a first polymerization step and a second polymerization step, wherein the first polymerization step involves emulsion polymerization of a radically polymerizable monomer component (M1) containing a monofunctional monomer (b1), and the second polymerization step involves emulsion polymerization of a radically polymerizable monomer component (M2) containing a monofunctional monomer (b2) and a crosslinkable monomer (a).

[15] In the method for producing resin microparticles described in

[14] above, the first polymerization step and the second polymerization step may be performed in a single reactor.

[16] In the method for producing resin microparticles described in

[14] or

[15] above, a reactive surfactant may be used in at least one selected from the first polymerization step and the second polymerization step.

[17] In the method for producing resin microparticles described in any one of

[14] to

[16] above, a water-soluble azo-based compound may be used as a polymerization initiator in at least one selected from the first polymerization step and the second polymerization step.

[18] In the method for producing resin microparticles according to any one of the above

[14] to

[17] , a non-reactive surfactant may not be used in the first polymerization step and the second polymerization step.

[19] In the method for producing resin microparticles according to any one of the above

[14] to

[18] , the monofunctional monomer (b2) in the second polymerization step may include an aromatic monofunctional monomer, and the crosslinkable monomer (a) may include an aromatic crosslinkable monomer.

[0010] According to an embodiment of the present invention, it is possible to provide resin microparticles that have reduced metal components and eluted ion components and have excellent dielectric properties. It is also possible to provide a method for producing such resin microparticles. It is also possible to provide uses of such resin microparticles.

[0011] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to these embodiments.

[0012] In this specification, the expression "(meth)acrylic" means "acrylic and / or methacrylic", the expression "(meth)acrylate" means "acrylate and / or methacrylate", and the expression "(meth)acrylonitrile" means "acrylonitrile and / or methacrylonitrile".

[0013] Resin Particles According to an embodiment of the present invention, the resin particles have a total content of the following component A of 100 ppm or less, and a total content of the following eluted ionic component B of 100 ppm or less. Component A: Al, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, P, S, Si, Sr, and Zn. Ionic component B: fluoride ions (F - ), chloride ions (Cl - ), nitrite ion (NO2 - ), bromide ion (Br - ), nitrate ions (NO3 - ), phosphate ions (PO4 3- ), and sulfate ions (SO 2- )

[0014] The total content of component A in the resin microparticles is measured by inductively coupled plasma (ICP) atomic emission spectrometry. The total amount of eluted ionic component B in the resin microparticles is measured by ion chromatography. In this specification, the total content of component A in the resin microparticles means the mass of component A per mass of the resin microparticles, and the total amount of eluted ionic component B in the resin microparticles means the mass of eluted ionic component B per mass of the resin microparticles. Therefore, 1 ppm = 1 mg / kg in terms of the total content of component A and the total amount of eluted ionic component B.

[0015] Thus, resin microparticles with a small total content of component A and a small total amount of eluted ionic component B do not affect the performance of fine components even when used in fine components, and are particularly suitable for use in fine semiconductor components. If the total content of component A in the resin microparticles exceeds 100 ppm, component A eluted from the resin microparticles may reduce the performance of components obtained by mixing the resin microparticles with resin, etc. Similarly, if the total amount of eluted ionic component B from the resin microparticles exceeds 100 ppm, ionic components eluted from the resin microparticles may reduce the performance of components obtained by mixing the resin microparticles with resin, etc. For example, when resin microparticles with a high total content of component A or a high total amount of eluted ionic component B are used in semiconductor components, component A and ionic component B eluted from the resin microparticles may cause ion migration.

[0016] The total content of component A in the resin microparticles according to an embodiment of the present invention is preferably 70 ppm or less, more preferably 50 ppm or less, even more preferably 30 ppm or less, still more preferably 20 ppm or less, particularly preferably 15 ppm or less, and most preferably 12 ppm or less. The lower limit of the total content of component A in the resin microparticles according to an embodiment of the present invention is, for example, 0 ppm or more, and may be 0.1 ppm or more.

[0017] The total amount of eluted ionic components B of the resin microparticles according to the embodiment of the present invention is preferably 100 ppm or less, more preferably 70 ppm or less, even more preferably 50 ppm or less, still more preferably 30 ppm or less, particularly preferably 15 ppm or less, and most preferably 12 ppm or less. The lower limit of the total amount of eluted ionic components B of the resin microparticles according to the embodiment of the present invention is, for example, 0 ppm or more, and may be 0.1 ppm or more.

[0018] The resin microparticles according to the present invention have a dielectric loss tangent of 0.0050 or less at a frequency of 10 GHz. Such resin microparticles with a low dielectric loss tangent themselves can exhibit the excellent dielectric properties of the resin in which they are mixed. Examples of excellent dielectric properties include a low dielectric constant and a low dielectric loss tangent.

[0019] The resin particles according to the embodiment of the present invention have a dielectric loss tangent at a frequency of 10 GHz of preferably 0.0040 or less, more preferably 0.0030 or less, even more preferably 0.0020 or less, particularly preferably 0.0015 or less, and most preferably 0.0010 or less. The lower limit of the dielectric loss tangent is preferably 0 or more.

[0020] The resin particles according to the embodiment of the present invention preferably have a relative dielectric constant at a frequency of 10 GHz of 1.0 to 2.5, more preferably 1.0 to 2.4, even more preferably 1.0 to 2.3, and particularly preferably 1.0 to 2.2.

[0021] The volume average particle diameter (volume average primary particle diameter) of the resin microparticles according to an embodiment of the present invention is not particularly limited and can be appropriately set depending on the purpose and application. The volume average particle diameter of the resin microparticles according to an embodiment of the present invention is, for example, 3 μm or less, preferably 2 μm or less, more preferably 1.5 μm or less, and even more preferably 1.0 μm or less. The volume average particle diameter of the resin microparticles according to an embodiment of the present invention is, for example, 0.05 μm or more, preferably 0.07 μm or more, and even more preferably 0.1 μm or more. The volume average particle diameter of the resin microparticles according to an embodiment of the present invention is preferably 0.05 μm or more and 2 μm or less, more preferably 0.08 μm or more and 2 μm or less, and even more preferably 0.1 μm or more and 1 μm or less. The volume average particle diameter can be measured, for example, using a laser diffraction / scattering particle size distribution analyzer manufactured by Beckman Coulter, Inc.

[0022] The coefficient of variation of the volume average particle diameter of the resin microparticles according to an embodiment of the present invention is not particularly limited and can be set appropriately depending on the purpose and use. The coefficient of variation of the volume average particle diameter of the resin microparticles according to an embodiment of the present invention is, for example, 40% or less, preferably 30% or less, more preferably 25% or less, and even more preferably 20% or less. The coefficient of variation of the volume average particle diameter of the resin microparticles according to an embodiment of the present invention may be, for example, 1% or more, 5% or more, or even 10% or more. The coefficient of variation of the volume average particle diameter of the resin microparticles is a numerical value calculated by the following formula (1) and represents the distribution width of the data. Coefficient of variation [%] = (standard deviation of volume-based particle size distribution of resin microparticles ÷ volume average particle diameter of resin microparticles) × 100 (1)

[0023] In the resin microparticles according to an embodiment of the present invention, the proportion of particles having a particle diameter of 10 μm or more is, for example, 0.01% by volume or less, and preferably 0% by volume. The proportion is measured by the proportion based on the number of particles, and for example, the method described in the Examples below can be used.

[0024] The resin microparticles according to the embodiment of the present invention are typically solid particles. The resin microparticles according to the embodiment of the present invention may be in the form of a dry powder or may be dispersed in a liquid (dispersion medium).

[0025] <Polymer P> The resin microparticles according to an embodiment of the present invention typically contain a polymer (P) obtained by the reaction of a composition containing a radical polymerizable monomer component (M). The monomer component (M) preferably contains a vinyl monomer, more preferably a crosslinkable monomer (a) and an aromatic monofunctional monomer (b). Therefore, a preferred embodiment of the polymer (P) has a structural unit derived from the crosslinkable monomer (a) and a structural unit derived from the aromatic monofunctional monomer (b).

[0026] The polymer (P) may be of one type only, or of two or more types.

[0027] The content of the polymer (P) in the resin microparticles according to an embodiment of the present invention is preferably 60% by mass to 100% by mass, more preferably 70% by mass to 100% by mass, even more preferably 80% by mass to 100% by mass, still more preferably 90% by mass to 100% by mass, particularly preferably 95% by mass to 100% by mass, and most preferably 98% by mass to 100% by mass, in order to further exhibit the effects of the present invention.

[0028] The crosslinkable monomer (a) has two or more double bonds in the molecule. Any appropriate crosslinkable monomer can be used as the crosslinkable monomer (a) as long as it is a monomer having crosslinkability (having two or more double bonds in the molecule) and does not impair the effects of the present invention. Examples of the crosslinkable monomer (a) include divinylbenzene, divinylnaphthalene, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, decaethylene glycol di(meth)acrylate, pentadecaethylene glycol di(meth)acrylate, pentacontahexaethylene glycol di(meth)acrylate, 1,3-butylene di(meth)acrylate, allyl (meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tetraacrylate, and neopentyl glycol di(meth)acrylate. In terms of being able to more effectively exhibit the effects of the present invention, the crosslinkable monomer (a) is preferably an aromatic crosslinkable monomer having an aromatic functional group and two or more radically polymerizable double bonds in the skeleton, such as divinylbenzene, divinylnaphthalene, etc., and more preferably divinylbenzene. The crosslinkable monomer (a) may be used alone or in combination of two or more.

[0029] As the aromatic monofunctional monomer (b), any appropriate aromatic monofunctional monomer can be used as long as it has a molecular structure having an aromatic functional group and one radically polymerizable double bond in the skeleton, as long as the effects of the present invention are not impaired. Examples of the aromatic monofunctional monomer (b) include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, t-butylstyrene, ethylvinylbenzene, vinylnaphthalene, styrene sulfonic acid, styrene sulfonate salts, vinylbenzoic acid, and vinylphenol. Examples of styrene sulfonate salts include sodium styrenesulfonate and ammonium styrenesulfonate. Examples of vinylbenzoic acid include o-vinylbenzoic acid, m-vinylbenzoic acid, and p-vinylbenzoic acid. Examples of vinylphenol include o-vinylphenol, m-vinylphenol, and p-vinylphenol. In order to further enhance the effects of the present invention, the aromatic monofunctional monomer (b) is preferably at least one selected from the group consisting of styrene, α-methylstyrene, t-butylstyrene, and ethylvinylbenzene, and more preferably at least one selected from the group consisting of styrene and ethylvinylbenzene. These aromatic monofunctional monomers (b) may be used alone or in combination of two or more.

[0030] The total content of the crosslinkable monomer (a) and the aromatic monofunctional monomer (b) in the monomer component (M) is preferably 50% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, even more preferably 90% by mass to 100% by mass, and particularly preferably 95% by mass to 100% by mass, in terms of being able to further exhibit the effects of the present invention.

[0031] The content of the crosslinkable monomer (a) in the monomer component (M) is preferably 1% by mass to 50% by mass, more preferably 2% by mass to 40% by mass, even more preferably 3% by mass to 30% by mass, still more preferably 5% by mass to 25% by mass, particularly preferably 8% by mass to 20% by mass, and most preferably 9% by mass to 18% by mass, in terms of being able to further exhibit the effects of the present invention.

[0032] The content of the aromatic monofunctional monomer (b) in the monomer component (M) is preferably 50% by mass to 99% by mass, more preferably 60% by mass to 98% by mass, even more preferably 70% by mass to 97% by mass, particularly preferably 75% by mass to 96% by mass, and most preferably 80% by mass to 95% by mass, in terms of being able to further exhibit the effects of the present invention.

[0033] The monomer component (M) may contain any other appropriate radical polymerizable monomer (m) different from the above-mentioned crosslinkable monomer (a) and monofunctional monomer (b) within the scope that does not impair the effects of the present invention. Therefore, the polymer (P) may have a structural unit derived from the crosslinkable monomer (a), a structural unit derived from the aromatic monofunctional monomer (b), and a structural unit derived from another radical polymerizable monomer (m).

[0034] Other radical polymerizable monomers (m) include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, isopentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, methyl ... isooctyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, isostearyl (meth)acrylate, nonadecyl (meth)acrylate, eicosyl (meth)acrylate, and the like. (Meth)acrylic acid alkyl esters having 1 to 20 carbon atoms in the alkyl group bonded to the ester; (meth)acrylic acid esters having an alicyclic structure in the ester moiety such as cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, and dicyclopentanyl (meth)acrylate; hydroxyalkyl (meth)acrylate monomers such as hydroxyethyl (meth)acrylate; (meth)acrylic acid, 2-methacryloyloxyethyl succinate, 2-methacryloyloxyethyl phthalate, and 2-methacryloyloxyethyl hexahydro Carboxy group-containing monomers such as phthalic acid, 2-methacryloyloxyethyl maleic acid, 2-acryloyloxyethyl hexahydrophthalic acid, 2-acryloyloxyethyl succinic acid, and 2-acryloyloxyethyl phthalic acid; glycidyl group-containing monomers such as glycidyl (meth)acrylate, allyl glycidyl ether, and 4-hydroxybutyl (meth)acrylate glycidyl ether; epoxy group-containing monomers such as 1,2-epoxy-4-vinylcyclohexane and (3,4-epoxycyclohexyl)methyl (meth)acrylate;Examples of such other radical polymerizable monomers (m) include acrylamide derivative monomers such as 4-vinylphenyl glycidyl ether (meth)acrylamide; (meth)acrylonitrile-based monomers, halogenated vinyl-based monomers such as vinyl chloride; vinyl carboxylate-based monomers such as vinyl acetate; olefin-based monomers such as ethylene; unsaturated imide-based monomers; vinyl alcohol; and silane coupling agents having a vinyl group. Such other radical polymerizable monomers (m) may be of only one type, or may be of two or more types. The monomer component (M) may not contain other radical polymerizable monomers (m);

[0035] The content of the other radical polymerizable monomer (m) in the monomer component (M) is preferably 0% by mass to 50% by mass, more preferably 0% by mass to 20% by mass, even more preferably 0% by mass to 10% by mass, particularly preferably 0% by mass to 5% by mass, and most preferably 0% by mass to 2% by mass, in terms of being able to further exhibit the effects of the present invention.

[0036] The content of the monomer component (M) in the composition is preferably 85% to 100% by mass, more preferably 90% to less than 100% by mass, even more preferably 95% to less than 100% by mass, particularly preferably 97% to less than 100% by mass, and most preferably 98% to 99% by mass, in order to further enhance the effects of the present invention. If the content of the monomer component (M) in the composition is too low and outside the above range, the effects of the present invention may not be achieved, and for example, excellent dielectric properties may not be achieved. Here, the monomer component (M) does not include the polymerization initiator and surfactant used in the polymerization reaction.

[0037] The composition preferably contains a reactive surfactant (A) in addition to the monomer component (M). Therefore, the polymer (P) preferably has a structural unit derived from the aromatic monofunctional monomer (b), a structural unit derived from the crosslinkable monomer (a), and a structural unit derived from the reactive surfactant (A), and may have a structural unit derived from the crosslinkable monomer (a), a structural unit derived from the aromatic monofunctional monomer (b), a structural unit derived from another radical polymerizable monomer (m), and a structural unit derived from the reactive surfactant (A).

[0038] The reactive surfactant (A) typically has one or more double bonds in the molecule. Examples of the reactive surfactant (A) include anionic reactive surfactants and nonionic reactive surfactants.

[0039] Examples of anionic reactive surfactants include JS-20 or RS-3000 from Sanyo Chemical Industries, Ltd., KH-10, KH-1025, KH-05, HS-10, HS-1025, BC-0515, BC-10, BC-1025, BC-20, BC-2020, AR-1025, and AR-2025 from Aqualon (registered trademark) from Dai-ichi Kogyo Seiyaku Co., Ltd., Antox (registered trademark) MS-60 from Nippon Nyukazai Co., Ltd., S-120, S-180A, S-180, and PD-104 from Latemul (registered trademark) from Kao Corporation, and SR-1025 or SE-10N from Adeka Reasoap (registered trademark) from ADEKA Corporation. From the viewpoint of improving the dispersibility of the resin particles, the anionic reactive surfactant preferably has an oxyalkylene chain in the molecular chain.

[0040] Examples of nonionic reactive surfactants include alkyl ether surfactants (commercially available products include Adeka Reasop ER-10, ER-20, ER-30, and ER-40 manufactured by ADEKA Corporation; and Latemul PD-420, PD-430, and PD-450 manufactured by Kao Corporation); alkyl phenyl ether surfactants or alkyl phenyl ester surfactants (commercially available products include Aqualon RN-10, RN-20, RN-30, RN-50, AN-10, AN-20, AN-30, and AN-5065 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; and Adeka Reasop NE-10, NE-20, NE-30, and NE-40 manufactured by ADEKA Corporation); and (meth)acrylate sulfate surfactants (commercially available products include RMA-564, RMA-568, and RMA-1114 manufactured by Nippon Nyukazai Co., Ltd.). From the viewpoint of dispersion stability of the resin particles, the nonionic reactive surfactant preferably has an oxyalkylene chain in the molecular chain.

[0041] The content of the reactive surfactant (A) in the composition is preferably 0 to 10 parts by mass, more preferably more than 0 to 8 parts by mass, even more preferably more than 0 to 5 parts by mass, particularly preferably more than 0 to 3 parts by mass, and most preferably 0.1 to 2 parts by mass, relative to 100 parts by mass of the total of the monomer components (M) (crosslinkable monomer (a), aromatic monofunctional monomer (b), and other radically polymerizable monomer (m)), in order to better exhibit the effects of the present invention. If the content is too high outside the above range, the effects of the present invention may not be exhibited, for example, excellent dielectric properties may not be exhibited. If the content is too low outside the above range, the effects of the present invention may not be exhibited, for example, the dispersion stability of the particles may be deteriorated, and resin fine particles may not be obtained.

[0042] <<Uses of Resin Microparticles>> Resin microparticles according to embodiments of the present invention can be used in a variety of applications. Because they can further utilize the effects of the present invention, resin microparticles according to embodiments of the present invention are suitable for use as additives for electronic materials such as semiconductor components, optical components such as light diffusers and anti-glare / low-reflection components, paint additives, and ink additives. In particular, resin microparticles according to embodiments of the present invention have a small particle diameter, reduced metal components and eluted ion components, and excellent dielectric properties. This makes it possible to produce small or thin semiconductor components containing a sufficient amount of resin microparticles, thereby preventing ion migration and improving dielectric properties.

[0043] <<Method for Producing Resin Particles>> The resin particles according to the embodiment of the present invention can be produced, for example, by emulsion polymerization of the above-mentioned monomers.

[0044] The method for producing resin microparticles according to an embodiment of the present invention typically includes two-stage polymerization steps: a first polymerization step and a second polymerization step. In the first polymerization step, a radically polymerizable monomer component (M1) containing a monofunctional monomer (b1) is emulsion-polymerized. In the second polymerization step, a radically polymerizable monomer component (M2) containing a monofunctional monomer (b2) and a crosslinkable monomer (a) is emulsion-polymerized.

[0045] Emulsion polymerization is a polymerization method in which a liquid medium, a monomer component that is poorly soluble in the medium, and a surfactant are mixed, and then a polymerization initiator that is soluble in the medium is added to the mixture to carry out polymerization. Emulsion polymerization can reduce the variation in particle size of resin microparticles.

[0046] According to the manufacturing method of the embodiment of the present invention, it is possible to manufacture resin microparticles that have reduced metal components and eluted ion components and have excellent dielectric properties.

[0047] The first polymerization step and the second polymerization step are preferably carried out in a single reactor, more preferably continuously in a single reactor. By carrying out the first polymerization step and the second polymerization step in a single reactor, the proportion of coarse particles in the resin fine particles can be reduced.

[0048] <First Polymerization Step> In the first polymerization step, typically, a monomer component (M1) containing a monofunctional monomer (b1) is emulsion polymerized to produce a crude product containing a polymer. The polymer is typically used as seed particles in the second polymerization step.

[0049] (Monofunctional Monomer) Examples of the monofunctional monomer (b1) include the monofunctional monomers listed as other radical polymerizable monomers (m) in the Polymer P of the above-mentioned Resin Fine Particles, and the monofunctional monomers listed as aromatic monofunctional monomers (b) in the Polymer P of the above-mentioned Resin Fine Particles. Methyl (meth)acrylate is preferred as the monofunctional monomer (b1). In some cases, styrene is preferred as the monofunctional monomer (b1). Alternatively, the monofunctional monomer (b1) may be the same material as the monofunctional monomer (b2) in the second polymerization step described below. The monofunctional monomer (b1) may be one type only, or two or more types.

[0050] The content of the monofunctional monomer (b1) in the monomer component (M1) is preferably 50% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, even more preferably 90% by mass to 100% by mass, particularly preferably 95% by mass to 100% by mass, and most preferably 98% by mass to 100% by mass, in terms of being able to further exhibit the effects of the present invention.

[0051] In the first polymerization step, as described above, emulsion polymerization is carried out using a composition containing the monomer component (M1), a liquid medium, a surfactant, and a polymerization initiator, thereby obtaining a crude product containing seed particles, which are polymers of the monomer component (M1), and the liquid medium.

[0052] (Liquid medium) The liquid medium used in the first polymerization step is not particularly limited. The liquid medium is, for example, water, an organic solvent, or a mixture thereof. In the production method according to an embodiment of the present invention, the liquid medium is preferably an aqueous medium, and for example, water, a lower alcohol such as methyl alcohol or ethyl alcohol, or a mixture of water and a lower alcohol can be used.

[0053] (Surfactant) Any appropriate surfactant may be used in the first polymerization step as long as it does not impair the effects of the present invention. The surfactant may be one type or two or more types. In order to further demonstrate the effects of the present invention, it is preferable that the surfactant contains a reactive surfactant. Examples of the reactive surfactant include anionic reactive surfactants and nonionic reactive surfactants. Examples of the anionic reactive surfactant include the anionic reactive surfactants listed as the reactive surfactant (A) in the <Polymer P> of the above-mentioned <<Resin Particles>>. Examples of the nonionic reactive surfactant include the nonionic reactive surfactants listed as the reactive surfactant (A) in the <Polymer P> of the above-mentioned <<Resin Particles>>. It is preferable that the surfactant does not contain a non-reactive surfactant.

[0054] In the first polymerization step, it is preferable not to use any other emulsifying aids other than the reactive surfactant.

[0055] The amount of the surfactant used in the first polymerization step is preferably 0.01 to 20 parts by mass, more preferably 0.05 to 18 parts by mass, and even more preferably 0.1 to 16 parts by mass, relative to 100 parts by mass of the monomer component (M1) in the first polymerization step.

[0056] (Polymerization initiator) Any appropriate polymerization initiator can be used in the first polymerization step as long as it does not impair the effects of the present invention. As the polymerization initiator, a radical polymerization initiator, particularly a thermal polymerization initiator, is preferred. Examples of polymerization initiators include water-soluble azo compounds, persulfates (e.g., ammonium persulfate, potassium persulfate, sodium persulfate, etc.), hydrogen peroxide, organic peroxides, and oil-soluble nitrile-azo compounds.

[0057] Examples of the polymerization initiator include 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine]n-hydrate (trade name "VA-057"), 4,4'-azobis(4-cyanovaleric acid) (trade name "V-501"), 2,2'-azobis[2-(2-imidazolin-2-yl)propane] and its dihydrochloride (trade names "VA-061" and "VA-044"), 2,2'-azobis[2-methyl-N- (2-hydroxyethyl)propionamide] (trade name "VA-086"), 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide} (trade name "VA-080"), 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)ethyl]propionamide} (trade name "VA-082"), 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)ethyl]propionamide} (trade name "VA-084"), 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)ethyl]propionamide} (trade name "VA-085"), 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)ethyl]propionamide} (trade name "VA-086 ... water-soluble azo compounds such as {N-[2-(1-hydroxybutyl)]-propionamide} (trade name "VA-085") (all manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.); organic peroxides such as cumene hydroperoxide, di-tert-butyl peroxide, dicumyl peroxide, benzoyl peroxide, lauroyl peroxide, dimethylbis(tert-butylperoxy)hexane, dimethylbis(tert-butylperoxy)hexyne-3, bis(tert-butylperoxyisopropyl)benzene, bis(tert-butylperoxy)trimethylcyclohexane, butyl-bis(tert-butylperoxy)valerate, tert-butyl 2-ethylhexaneperoxyate, dibenzoyl peroxide, paramenthane hydroperoxide, and tert-butyl peroxybenzoate;2,2'-Azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2-isopropylbutyronitrile), 2,2'-azobis(2,3-dimethylbutyronitrile), 2,2'-azobis(2,4-dimethylbutyronitrile), 2,2'-azobis(2-methylcapronitrile), 2,2'-azobis(2,3,3-trimethylbutyronitrile), 2,2'-azobis(2,4,4-trimethylvaleronitrile), 2,2'-azobis oil-soluble nitrile-azo compounds such as 2,4-dimethylvaleronitrile, 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis(4-ethoxy-2,4-dimethylvaleronitrile), 2,2'-azobis(4-n-butoxy-2,4-dimethylvaleronitrile), 1,1'-azobis(cyclohexane-1-carbonitrile), 2-(carbamoylazo)isobutyronitrile, and 4,4'-azobis(4-cyanopentanoic acid);Furthermore, redox initiators obtained by combining the above-mentioned persulfate and organic peroxide polymerization initiators with reducing agents such as sodium sulfoxylate formaldehyde, sodium bisulfite, ammonium bisulfite, sodium thiosulfate, ammonium thiosulfate, hydrogen peroxide, sodium hydroxymethanesulfinate, L-ascorbic acid or its salts, cuprous salts, and ferrous salts may also be used as polymerization initiators. Among these, 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine]n-hydrate (trade name "VA-057"), 4,4'-azobis(4-cyanovaleric acid) (trade name "V-501"), 2,2'-azobis[2-(2-imidazolin-2-yl)propane] (trade name "VA-061"), 2,2'-azobis[2-methyl-N-(2-hydroxyethyl) )propionamide] (trade name "VA-086"), 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide} (trade name "VA-080"), 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)ethyl]propionamide} (trade name "VA-082"), 2,2'-azobis{2-methyl-N It is preferable to use one or more compounds selected from the group consisting of water-soluble azo compounds such as {2-(1-hydroxybutyl)]-propionamide} (trade name "VA-085") (both manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane-1-carbonitrile), 4,4'-azobis(4-cyanopentanoic acid), cumene hydroperoxide, di-tert-butyl peroxide, dicumyl peroxide, benzoyl peroxide, and lauroyl peroxide, and it is more preferable to use a water-soluble azo compound. This allows the total content of component A and the total amount of eluted ionic component B in the resin microparticles to be reduced. These polymerization initiators may be used alone or in combination of two or more.

[0058] The amount of the polymerization initiator used in the first polymerization step is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, and even more preferably 0.1 to 1 part by mass, relative to 100 parts by mass of the monomer component (M1) in the first polymerization step.

[0059] The polymerization temperature in the first polymerization step may be any suitable temperature suitable for emulsion polymerization, as long as it does not impair the effects of the present invention. Such a polymerization temperature is preferably 30°C to 120°C, more preferably 50°C to 90°C.

[0060] The polymerization time for the first polymerization step may be any suitable time suitable for emulsion polymerization, as long as it does not impair the effects of the present invention. The polymerization time is preferably 1 hour to 48 hours, more preferably 1 hour to 24 hours, at the initial temperature of polymerization.

[0061] <Second Polymerization Step> In the second polymerization step, emulsion polymerization is carried out using a composition containing the radically polymerizable monomer component (M2). The composition typically contains a liquid medium, the monomer component (M2), a surfactant, and may further contain a polymerization initiator.

[0062] In the second polymerization step, typically, the monomer component (M2) is emulsion-polymerized in the presence of the polymer obtained in the first polymerization step. That is, the emulsion polymerization in the second polymerization step is seed emulsion polymerization using the polymer obtained in the first polymerization step as seed particles. In the second polymerization step, it is preferable to carry out polymerization by adding a composition containing the monomer component (M2) to the polymer (seed particles) obtained in the first polymerization step.

[0063] Seeded emulsion polymerization is a method in which a polymer is used as seed particles and a water-soluble polymerization initiator is used to grow the seed particles while polymerizing a monomer. That is, seeded emulsion polymerization is an emulsion polymerization in which a liquid medium, a monomer component that is poorly soluble in the medium, and a surfactant are mixed in the presence of seed particles made of a polymer, and a polymerization initiator that is soluble in the medium is added to carry out polymerization.

[0064] The seed particles may be in the form of a dispersion. In the second polymerization step, it is preferable to carry out polymerization by adding a composition containing the monomer component (M2) to the crude product obtained in the first polymerization step.

[0065] As described above, the first polymerization step and the second polymerization step are preferably carried out in a single reactor. Therefore, the second polymerization step is preferably carried out in the same reactor as the first polymerization step, and more preferably carried out continuously after the first polymerization step in the reactor in which the first polymerization step was carried out. Therefore, the second polymerization step is preferably carried out by introducing a composition containing the monomer component (M2) into the reactor used in the first polymerization step, which contains the crude product of the first polymerization step, to carry out seed emulsion polymerization. Here, carrying out the first polymerization step and the second polymerization step continuously means, for example, carrying out the second polymerization step without removing the polymer (seed particles) from the reactor after emulsion polymerization in the first polymerization step and / or without intentionally lowering the temperature of the reactor (i.e., without cooling the crude product of the first polymerization step).

[0066] (Crosslinkable Monomer) The crosslinkable monomer (a) is the same as the crosslinkable monomer (a) exemplified in <Polymer P> in the above-mentioned <<Resin Fine Particles>>. The crosslinkable monomer (a) may be used alone or in combination of two or more.

[0067] (Monofunctional Monomer) The monofunctional monomer (b2) is preferably an aromatic monofunctional monomer. Examples of the aromatic monofunctional monomer include the monofunctional monomers listed as the aromatic monofunctional monomer (b) in <Polymer P> of the above-mentioned <<Resin Fine Particles>>. The monofunctional monomer (b2) is preferably at least one selected from the group consisting of styrene, α-methylstyrene, t-butylstyrene, and ethylvinylbenzene, and more preferably at least one selected from the group consisting of styrene and ethylvinylbenzene. These aromatic monofunctional monomers (b2) may be used alone or in combination of two or more.

[0068] The total content of the crosslinkable monomer (a) and the monofunctional monomer (b2) in the monomer component (M2) is preferably 50% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, even more preferably 90% by mass to 100% by mass, particularly preferably 95% by mass to 100% by mass, and most preferably 98% by mass to 100% by mass, in terms of being able to further exhibit the effects of the present invention.

[0069] (Liquid Medium) The liquid medium used in the second polymerization step is not particularly limited, and the medium described in the first polymerization step can be used, and the preferred range is also the same as that described in the first polymerization step. In the production method according to an embodiment of the invention, the liquid medium is preferably an aqueous medium, and for example, water, a lower alcohol such as methyl alcohol or ethyl alcohol, a mixture of water and a lower alcohol, etc. can be used.

[0070] The amount of the liquid medium used may be any appropriate amount as long as it does not impair the effects of the present invention. The amount of the medium at the start of the second polymerization step (for example, the total amount of the medium used in the first polymerization step and the second polymerization step) is preferably 10 parts by mass to 5,000 parts by mass, more preferably 50 parts by mass to 3,000 parts by mass, even more preferably 100 parts by mass to 2,000 parts by mass, and particularly preferably 120 parts by mass to 1,000 parts by mass, relative to 100 parts by mass of the total amount of the monomer component (M1) and the monomer component (M2).

[0071] (Surfactant) Any appropriate surfactant may be used in the second polymerization step as long as it does not impair the effects of the present invention. In the second polymerization step, the surfactant described in the first polymerization step can be used. The surfactant may be one type or two or more types. In order to further demonstrate the effects of the present invention, it is preferable that the surfactant contains a reactive surfactant.

[0072] When a surfactant is used in the second polymerization step, the amount of the surfactant used (the amount added during the second polymerization step) is preferably 0.05 to 7 parts by mass, more preferably 0.1 to 5 parts by mass, and even more preferably 0.15 to 3 parts by mass, relative to 100 parts by mass of the total amount of the monomer component (M1) and the monomer component (M2).

[0073] The total amount of surfactants used in the production method according to the embodiment of the present invention is preferably 0.05 to 7 parts by mass, more preferably 0.1 to 5 parts by mass, and even more preferably 0.15 to 4 parts by mass, relative to 100 parts by mass of the total amount of monomer component (M1) and monomer component (M2).

[0074] A reactive surfactant is preferably used in at least one selected from the first polymerization step and the second polymerization step, i.e., at least one selected from the composition containing the monomer component (M1) in the first polymerization step and the composition containing the monomer component (M2) in the second polymerization step preferably contains a reactive surfactant.

[0075] In the first polymerization step and the second polymerization step, a non-reactive surfactant can be used as long as it does not impair the effects of the present invention, but it is preferable not to use a non-reactive surfactant. That is, the composition containing the monomer component (M1) in the first polymerization step and the composition containing the monomer component (M2) in the second polymerization step preferably contain a reactive surfactant. Examples of the non-reactive surfactant include anionic non-reactive surfactants such as sodium oleate; fatty acid soaps such as castor oil potassium soap; alkyl sulfate ester salts such as sodium lauryl sulfate and ammonium lauryl sulfate; alkyl benzene sulfonates such as sodium dodecyl benzene sulfonate; alkyl naphthalene sulfonates; alkanesulfonates; dialkyl sulfosuccinates; alkyl phosphate ester salts; naphthalene sulfonate-formalin condensates; polyoxyethylene alkyl phenyl ether sulfate ester salts; polyoxyethylene sulfonated phenyl ether phosphate; polyoxyethylene alkyl ether phosphate; polyoxyethylene alkyl sulfate ester salts; and the like. Examples of the surfactant include nonionic reactive surfactants such as sialic acid tridecyl ether, polyoxyethylene isodecyl ether, polyoxyalkylene lauryl ether, polyether polyol, polyoxyethylene styrenated phenyl ether, polyoxyethylene naphthyl ether, polyoxyethylene phenyl ether, polyoxyethylene polyoxypropylene glycol, polyoxyethylene lauryl ether, polyoxyethylene oleyl cetyl ether, polyoxyethylene glyceryl isostearate, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxysorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin fatty acid ester, and oxyethylene-oxypropylene block polymer.

[0076] (Polymerization initiator) As the polymerization initiator used in the second polymerization step, any appropriate polymerization initiator can be used as long as it is a radical polymerization initiator and does not impair the effects of the present invention. In the second polymerization step, the polymerization initiators listed in the first polymerization step can be used, and the preferred ranges are the same as those described in the first polymerization step. The polymerization initiator used in the first polymerization step and the polymerization initiator used in the second polymerization step may be the same.

[0077] In at least one selected from the first polymerization step and the second polymerization step, a water-soluble azo compound is preferably used as the polymerization initiator.

[0078] The amount of the polymerization initiator used in the second polymerization step (the amount added during the second polymerization step) is preferably 0.05 to 5.0 parts by mass, more preferably 0.08 to 3.0 parts by mass, and even more preferably 0.1 to 2.0 parts by mass, relative to 100 parts by mass of the total amount of the monomer component (M1) and the monomer component (M2).

[0079] The total amount of the polymerization initiators used in the production method according to the embodiment of the present invention is preferably 0.05 to 5.0 parts by mass, more preferably 0.08 to 3.0 parts by mass, and even more preferably 0.1 to 2.0 parts by mass, relative to 100 parts by mass of the total amount of the monomer component (M1) and the monomer component (M2).

[0080] The polymerization temperature in the second polymerization step may be any appropriate temperature suitable for emulsion polymerization, as long as it does not impair the effects of the present invention. Such a polymerization temperature is preferably 30°C to 120°C, more preferably 50°C to 100°C. The polymerization temperature in the second polymerization step may be, for example, 30°C to 90°C as the initial temperature of the polymerization, and then the temperature may be increased to 70°C to 120°C as the temperature in the later stage of the polymerization.

[0081] The polymerization time for the second polymerization step may be any suitable time suitable for emulsion polymerization, as long as it does not impair the effects of the present invention. The polymerization time is preferably 1 hour to 48 hours, more preferably 1 hour to 24 hours, at the initial temperature of polymerization.

[0082] <Other Steps> After the second polymerization step, the particles may be washed, classified, dried, etc., if necessary.

[0083] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples.

[0084] <Volume Average Particle Diameter> The volume average particle diameter of the resin microparticles was measured using a laser diffraction / scattering particle size distribution analyzer (manufactured by Beckman Coulter, Inc., "LS 13 320"). A dispersion of the resin microparticles was subjected to measurement to obtain the volume-based particle size distribution of the resin microparticles and its standard deviation. The arithmetic mean diameter in the obtained volume-based particle size distribution was taken as the volume average particle diameter of the resin microparticles. The measurement conditions for the laser diffraction / scattering particle size distribution analyzer were as follows: Sample dispersion module: Universal liquid module Medium: Ion-exchanged water Refractive index of medium: 1.333 Refractive index of sample: Refractive index of resin microparticles The refractive index of the resin microparticles was calculated by averaging the refractive indexes of the homopolymers of each monomer used in the production, weighted by the amount of each monomer used.

[0085] <Coefficient of variation of volume average particle diameter> The coefficient of variation (CV value) of the volume average particle diameter of the resin fine particles was calculated by the following formula: Coefficient of variation [%] = (standard deviation of volume-based particle size distribution of resin fine particles / volume average particle diameter of resin fine particles) × 100

[0086] <Proportion of particles with a particle diameter of 10 μm or more> The proportion of particles with a particle diameter of 10 μm or more was measured using a Coulter Multisizer. TM Measurements are performed using a Multisizer 4e (measurement device manufactured by Beckman Coulter, Inc.). TM The measurement is performed using an aperture calibrated in accordance with the 4e user's manual. The aperture used for the measurement is selected appropriately depending on the size of the resin microparticles to be measured. The Current (aperture current) and Gain are set appropriately depending on the size of the selected aperture. For example, if an aperture with a size of 50 μm is selected, the Current (aperture current) is set to -800 and the Gain is set to 4. The measurement sample is a dispersion prepared by dispersing 0.1 g of resin microparticles in 10 ml of a 0.1 wt % polyoxyethylene sorbitan monolaurate "Tween 20" aqueous solution using a touch mixer (manufactured by Yamato Scientific Co., Ltd., "TOUCHMIXER MT-31") and an ultrasonic cleaner (manufactured by Vervoclear Co., Ltd., "ULTRASONIC CLEANER VS-150") to prepare the dispersion. During the measurement, the contents of the beaker were gently stirred to an extent that no air bubbles were introduced, and the measurement was stopped when 100,000 resin microparticles were measured. The proportion of particles with sizes of 10 μm or more was confirmed in the volume-based particle size distribution obtained from the measurement results.

[0087] <Total Content of Component A> (Measurement Sample) A dispersion containing resin fine particles was dried using a spray dryer (manufactured by Sakamoto Giken Co., Ltd., machine name: spray dryer, model: atomizer take-up system, model number: TRS-3WK) under the following device conditions to prepare a measurement sample. (Spray dryer device conditions) Supply rate of dispersion containing resin fine particles: 25 mL / min Atomizer rotation speed: 12,000 rpm Air volume: 2 m 3 / min Inlet temperature (inlet temperature of the inlet port equipped in the spray dryer through which the dispersion liquid containing resin fine particles is sprayed and introduced): 150°C Outlet temperature (outlet temperature of the outlet port equipped in the spray dryer through which the dried particles are discharged): 70°C (Measurement method) The total content of component A was measured as follows. Approximately 1.0 g of the above-mentioned precisely weighed measurement sample was heated at 500°C for 1 hour to be incinerated. The resulting ash was mixed with 1 mL of concentrated hydrochloric acid (Ultrapur-100 ultra-high purity reagent manufactured by Kanto Chemical Co., Ltd.). The insoluble matter in the mixture was filtered through ADVANTEC No. 7 filter paper, and the filtrate was diluted to 25 mL with distilled water to prepare a test solution. ICP atomic emission spectroscopy was performed on the test solution under the following conditions. The concentration of each measured element was determined from a previously prepared calibration curve. The component amount of each measured element was calculated using the following formula. Component amount [ppm] = measured element concentration [μg / mL] × 25 [mL] ÷ sample amount [g] The total content (total) of component A was calculated from the component amount of each measured element. Here, in calculating the total content of component A, elements whose measurement results were below the lower limit of quantitation were not taken into consideration. In other words, the total content of component A was taken as the sum of the component amounts of elements equal to or above the lower limit of quantitation. The lower limits of quantitation for P and K were 0.5 ppm, and the lower limits of quantitation for other elements were 0.3 ppm. (ICP measurement conditions) Measurement device: Shimadzu Corporation "ICPE-9000" multi-type ICP optical emission spectrometer Measurement elements: Al, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, P, S, Si, Sr, Zn Observation direction: axial High frequency output: 1.20 kW Carrier flow rate: 0.7 L / min Plasma flow rate: 10.0 L / min Auxiliary flow rate: 0.6 L / min Exposure time: 30 seconds Standard solutions for calibration curve: SPEX USA "XSTC-13" general-purpose mixed standard solution 31 element mixture (base 5% HNO3) approximately 10 mg / L each, "XSTC-8" general-purpose mixed standard solution 13 element mixture (base H2O / trace HF) approximately 10 mg / L each (Ashing conditions) Measurement device: Microwave muffle furnace Phoenixix large capacity type (CEM) Ashing conditions: 500°C x 1 hr (sample amount = approximately 1.0 g)

[0088] <Total Amount of Eluted Ion Component B> (Measurement Sample) The obtained resin microparticles were dried using a spray dryer under the same conditions as those for the above <Total Content of Component A>, and this was used as the measurement sample. (Measurement Method) Eluted ion component B was measured as follows. A 50 mL container was prepared, and approximately 50 mL of ion-exchanged water was added and washed three times. Approximately 0.2 g of the measurement sample was precisely weighed into the washed 50 mL container. 1 mL of cleaning ethanol (Cleansolve P) was added and mixed well, and then 50 mL of ion-exchanged water was added and mixed well. The resulting mixture was subjected to ultrasonic cleaning and extraction for approximately 10 minutes, and then filtered through an aqueous 0.20 μm chromatographic disc to prepare the test solution used for ion chromatography measurement. A standard solution was measured under the following measurement conditions to create a calibration curve. Next, the test solution was measured under the same conditions. The peak area values ​​of each ion obtained from the chromatogram were used to determine the concentration of each measurement ion in the measurement sample from the calibration curve. The standard solution used for the calibration curve was "Anion Mixed Standard Solution 1" manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. The amount of eluted ionic components for each measured ion in the sample was calculated using the following formula: Amount of eluted ionic component [ppm] = Measured ion concentration [μg / mL] × 51 [mL] ÷ Sample amount [g] The total amount (total) of eluted ionic component B was calculated from the amount of eluted ionic component for each measured ion. Here, in calculating the total amount of eluted ionic component B, ions whose measurement results were below the lower limit of quantitation were not taken into consideration. In other words, the total amount of eluted ionic component B was determined as the sum of the amounts of eluted ionic components for ions equal to or above the lower limit of quantitation. The lower limit of quantitation was 2 ppm. (Ion chromatographic measurement conditions) Measurement device: "IC-2001" manufactured by Tosoh Corporation Measurement ion: F - , Cl - , NO2 - ,Br - , NO3 - , PO4 3- , SO4 2- Column: "TSKGEL superIC-AZ" manufactured by TOSOH Corporation Mobile phase: 3.2 mM Na2CO3 + 1.9 mM NaHCO3 Flow rate: 0.8 mL / min Column temperature: 40°C Injection volume: 30 μL

[0089] <Dielectric Properties of Resin Microparticles> (Measurement Sample) The obtained resin microparticles were dried using a spray dryer under the same conditions as in the above <Total Content of Component A>, and this was used as a measurement sample. (Measurement Method) The dielectric properties of the measurement sample were measured using a dielectric constant measurement device (ADMS01Nc series) manufactured by AET Corporation. The measurement was performed at a frequency of 10 GHz, in a measurement environment of 23°C, and at a relative humidity of 51±1%. The relative dielectric constant and dielectric loss tangent of the resin microparticles were calculated based on perturbation theory using a resonator.

[0090] Example 1 In a pressure-resistant polymerization reactor equipped with a stirrer, thermometer, and cooling mechanism, 240 parts by mass of ion-exchanged water and 0.03 parts by mass of Aqualon AR-1025 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., pure content 25%) as a reactive surfactant were mixed to prepare a first aqueous phase. Next, 4 parts by mass of methyl methacrylate were added to the reactor, and nitrogen gas was blown in for 3 minutes, followed by sealing and heating to 60°C. In a separate container, 0.04 parts by mass of 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] n-hydrate as a polymerization initiator was dissolved in 2 parts by mass of ion-exchanged water to prepare a polymerization initiator solution. The polymerization initiator solution was added to the reactor, which had reached 60°C, and a polymerization reaction was carried out for 2 hours (first polymerization step).

[0091] In a separate vessel, 76 parts by mass of ion-exchanged water, 0.9 parts by mass of Aqualon AR-1025 as a reactive surfactant, and 0.36 parts by mass of 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] n-hydrate as a polymerization initiator were mixed to prepare a second aqueous phase. Next, a mixture of 67 parts by mass of styrene and 9 parts by mass of divinylbenzene (NS Styrene Monomer Co., Ltd., DVB-810) was added to the second aqueous phase, and the mixture was stirred at 8,000 rpm for 10 minutes using a TK Homomixer (manufactured by Primix Corporation) to obtain a monomer mixture. After the first polymerization step was completed, the monomer mixture was added over 3 hours to the reactor. After the addition was completed, polymerization was continued at 60°C for 2 hours, and then the temperature was raised to 85°C and polymerization was continued for another 2 hours (second polymerization step).

[0092] After the polymerization reaction was completed, the resulting dispersion was cooled and then classified by passing it through a 500 Mesh (opening 24 μm) screen to obtain a dispersion containing resin microparticles of Example 1. The volume average particle diameter of the resin microparticles of Example 1 was 0.36 μm, and the coefficient of variation (CV value) of the volume average particle diameter was 14%. The resin microparticles of Example 1 had a particle ratio of particles having a particle diameter of 10 μm or more of 0 vol%. The measurement results of the total content of component A and the total amount of eluted ionic component B of the resin microparticles of Example 1 are shown in Table 1.

[0093] [Example 2] Resin microparticles of Example 2 were obtained in the same manner as in Example 1, except that the amount of Aqualon AR-1025 used in the first polymerization step was changed from 0.03 parts by mass to 2.5 parts by mass. The volume average particle diameter of the resin microparticles of Example 2 was 0.13 μm, and the coefficient of variation (CV value) of the volume average particle diameter was 19%. The resin microparticles of Example 2 had a content of particles having a particle diameter of 10 μm or more of 0% by volume. The measurement results of the total content of component A and the total amount of eluted ionic component B of the resin microparticles of Example 2 are shown in Table 1.

[0094] Example 3 In a pressure-resistant polymerization reactor equipped with a stirrer, thermometer, and cooling mechanism, 240 parts by mass of ion-exchanged water and 0.01 parts by mass of Aqualon AR-1025 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., pure content 25%) as a reactive surfactant were mixed to prepare a first aqueous phase. Next, 4 parts by mass of methyl methacrylate were added to the reactor, and nitrogen gas was blown in for 3 minutes. The reactor was then sealed and heated to 75°C. In a separate container, 0.04 parts by mass of 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide] as a polymerization initiator was dissolved in 2 parts by mass of ion-exchanged water to prepare a polymerization initiator solution. The polymerization initiator solution was added to the reactor, which had reached 75°C, and a polymerization reaction was carried out for 2 hours (first polymerization step).

[0095] In a separate vessel, 76 parts by weight of ion-exchanged water, 0.8 parts by weight of Aqualon AR-1025 as a reactive surfactant, and 0.36 parts by weight of 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide] as a polymerization initiator were mixed to prepare a second aqueous phase. Next, a mixture of 54 parts by weight of styrene and 22 parts by weight of divinylbenzene (NS Styrene Monomer Co., Ltd., DVB-810) was added to the second aqueous phase, and the mixture was stirred at 8,000 rpm for 10 minutes using a TK Homomixer (manufactured by Primix Corporation) to obtain a monomer mixture. After the first polymerization step was completed, the monomer mixture was added over 5 hours to the reactor. After the addition was complete, the temperature was raised to 85°C and polymerization was carried out for 3 hours, and then the temperature was further raised to 100°C and polymerization was carried out for 5 hours (second polymerization step).

[0096] After the polymerization reaction was completed, the resulting dispersion was cooled and then classified by passing it through a 500 Mesh (opening 24 μm) screen to obtain a dispersion containing resin microparticles of Example 3. The volume average particle diameter of the resin microparticles of Example 3 was 0.58 μm, and the coefficient of variation (CV value) of the volume average particle diameter was 13%. The resin microparticles of Example 3 had a particle ratio of particles having a particle diameter of 10 μm or more of 0 vol%. The measurement results of the total content of component A and the total amount of eluted ion component B of the resin microparticles of Example 3 are shown in Table 1.

[0097] Example 4 Resin microparticles of Example 4 were obtained in the same manner as in Example 1, except that the reactive surfactant in the first polymerization step was changed from 0.03 parts by mass of Aqualon AR-1025 to 0.02 parts by mass of Eleminol JS-20 (manufactured by Sanyo Chemical Industries, Ltd., pure content 40%), and the reactive surfactant in the second polymerization step was changed from 0.9 parts by mass of Aqualon AR-1025 to 0.8 parts by mass of Eleminol JS-20 (manufactured by Sanyo Chemical Industries, Ltd., pure content 40%). The volume average particle diameter of the resin microparticles of Example 4 was 0.34 μm, and the coefficient of variation (CV value) of the volume average particle diameter was 13%. The resin microparticles of Example 4 had a proportion of particles having a particle diameter of 10 μm or more of 0% by volume. The measurement results of the total content of component A and the total amount of eluted ionic component B of the resin microparticles of Example 4 are shown in Table 1.

[0098] [Example 5] The same procedure as in Example 1 was carried out, except that 9 parts by mass of divinylbenzene (NS Styrene Monomer Co., Ltd., DVB-810) in the second polymerization step was changed to 9 parts by mass of neopentyl glycol dimethacrylate, to obtain resin microparticles of Example 5. The volume average particle diameter of the resin microparticles of Example 5 was 0.37 μm, and the coefficient of variation (CV value) of the volume average particle diameter was 14%. The resin microparticles of Example 5 had a presence rate of particles having a particle diameter of 10 μm or more of 0% by volume. The measurement results of the total content of component A and the total amount of eluted ionic component B of the resin microparticles of Example 5 are shown in Table 1.

[0099] <Production Example 1> In a reactor equipped with a stirrer, thermometer, and cooling mechanism, 270 parts by weight of ion-exchanged water and 0.07 parts by weight of sodium styrene sulfonate as an emulsification aid were mixed to prepare an aqueous phase. Next, a mixture of 120 parts by weight of methyl methacrylate and 2.4 parts by weight of 1-octanethiol as a chain transfer agent was added to the aqueous phase in the reactor. After purging the reactor with nitrogen for 5 minutes, the temperature was raised to 80°C. Upon reaching 80°C, a polymerization initiator solution prepared by dissolving 0.05 parts by weight of potassium persulfate as a polymerization initiator in 10 parts by weight of ion-exchanged water was added. Thereafter, nitrogen purging was again carried out for 5 minutes, and the mixture was stirred at 80°C for 5 hours to carry out an emulsion polymerization reaction. The mixture was then further heated to 100°C, maintained at that temperature for 3 hours, and then cooled to prepare a resin particle-containing slurry. This was used as seed particles.

[0100] Comparative Example 1: An aqueous phase was prepared by mixing 70 parts by weight of ion-exchanged water and 0.35 parts by weight of Eleminol JS-20 (a reactive surfactant) in a container. In a separate container, 61 parts by weight of styrene and 9 parts by weight of divinylbenzene (NS Styrene Monomer, DVB-810) were thoroughly mixed to prepare an oil phase. The oil phase was added to the aqueous phase and stirred at 8,000 rpm for 10 minutes using a TK Homomixer (Primix Corporation), yielding a monomer mixture. A reactor equipped with a stirrer, thermometer, and cooling mechanism was charged with 220 parts by weight of ion-exchanged water and 33 parts by weight of the seed particles prepared in Production Example 1. After purging with nitrogen for 5 minutes, the mixture was heated to 70°C. In a separate container, a polymerization initiator solution was prepared by dissolving 0.2 parts by weight of 4,4'-azobis(4-cyanovaleric acid) as a polymerization initiator in a mixture of 5 parts by weight of ethanol and 5 parts by weight of ion-exchanged water. When the temperature inside the reactor reached 70°C, a polymerization initiator solution was added. The monomer mixture was then added to the reactor over 4 hours, and a polymerization reaction was carried out. After the reaction, the temperature was further increased to 95°C, and the reaction was carried out for 3 hours. After the polymerization reaction, the resulting dispersion was cooled and classified by passing it through a 400 Mesh screen, thereby obtaining a dispersion containing resin microparticles of Comparative Example 1. The volume average particle diameter of the resin microparticles of Comparative Example 1 was 0.38 μm, and the coefficient of variation of the volume average particle diameter was 15%.

[0101] Comparative Example 2 The same procedure as in Comparative Example 1 was carried out, except that 0.35 parts by mass of Eleminol JS-20 was changed to 0.21 parts by mass of a non-reactive surfactant, Phosphanol RS-610 (manufactured by Toho Chemical Industry Co., Ltd.), to obtain a dispersion containing resin microparticles for Comparative Example 2. The volume average particle diameter of the resin microparticles for Comparative Example 2 was 0.37 μm, and the coefficient of variation of the volume average particle diameter was 15%.

[0102]

[0103] From the results in Table 1, it can be seen that the resin particles obtained in Examples 1 to 5 had reduced total content of component A and total amount of eluted ionic component B, and also had excellent dielectric properties.

[0104] The resin particles according to the embodiment of the present invention can be used for semiconductor members and the like.

Claims

1. Resin particles having a total content of component A of 100 ppm or less as measured by inductively coupled plasma atomic emission spectrometry, a total content of eluted ion component B of 100 ppm or less as measured by ion chromatography, and a dielectric loss tangent of 0.0050 or less at a frequency of 10 GHz, where component A is Al, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, P, S, Si, Sr, and Zn, and ion component B is fluoride ion, chloride ion, nitrite ion, bromide ion, nitrate ion, phosphate ion, and sulfate ion.

2. The resin particles according to claim 1, wherein the dielectric loss tangent is 0.0030 or less.

3. The resin microparticles according to claim 1, comprising a polymer (P) obtained by the reaction of a composition containing a radically polymerizable monomer component (M), wherein the monomer component (M) contains a crosslinkable monomer (a) and an aromatic monofunctional monomer (b).

4. The resin particles according to claim 3, wherein the crosslinkable monomer (a) includes an aromatic crosslinkable monomer.

5. The resin particles according to claim 3, wherein the composition contains a reactive surfactant (A).

6. The resin particles according to claim 1, having a volume average particle size of 0.05 μm or more and 2 μm or less.

7. The resin particles according to claim 1, wherein the proportion of particles having a particle diameter of 10 μm or more is 0.01% by volume or less.

8. The resin microparticles according to claim 1, which are in the form of a dry powder.

9. The resin particles according to claim 1, wherein the coefficient of variation of the volume average particle diameter is 25% or less.

10. The resin particles according to any one of claims 1 to 9, which are used as an additive for electronic materials.

11. The resin particles according to any one of claims 1 to 9, which are used as an additive for optical materials.

12. The resin microparticles according to any one of claims 1 to 9, which are used as a paint additive.

13. The resin microparticles according to any one of claims 1 to 9, which are used as an ink additive.

14. A method for producing resin microparticles according to any one of claims 1 to 9, comprising carrying out two-stage polymerization consisting of a first polymerization step and a second polymerization step, wherein in the first polymerization step, a radical polymerizable monomer component (M1) containing a monofunctional monomer (b1) is emulsion polymerized, and in the second polymerization step, a radical polymerizable monomer component (M2) containing a monofunctional monomer (b2) and a crosslinkable monomer (a) is emulsion polymerized.

15. The method for producing resin microparticles according to claim 14, wherein the first polymerization step and the second polymerization step are carried out in a single reactor.

16. The method for producing resin microparticles according to claim 14, wherein a reactive surfactant is used in at least one selected from the first polymerization step and the second polymerization step.

17. The method for producing resin microparticles according to claim 14, wherein a water-soluble azo compound is used as a polymerization initiator in at least one selected from the first polymerization step and the second polymerization step.

18. The method for producing resin microparticles according to claim 14, wherein a non-reactive surfactant is not used in the first polymerization step and the second polymerization step.

19. A method for producing resin microparticles according to claim 14, wherein the monofunctional monomer (b2) in the second polymerization step includes an aromatic monofunctional monomer, and the crosslinkable monomer (a) includes an aromatic crosslinkable monomer.